Principles and Applications

of Magnetic Sensors

Dept of Photonics and Sensors

Hannam University

Prof Derac Son

Quantitiesto be

measured

Transduceror

Sensor

(Mostly)ElectricalQuantity

What is sensor

INTRODUCTION OF SENSORS

Quantitiesto be

measured

Transduceror

Sensor

ADC amp Embeddedcontroller

Computer

Why are sensors important

Real World

Computerand

Network

Sensor

(smart phone)

Traditionally sensors are used for research and production

World market of sensors

West European market of sensorsWest European market of sensors

Sensor VariablesSecondary

Signal

Primary

Signal

Mechanical Thermal Electrical Magnetic Radiant Chemical

Mechanical

(Fluid) Mechanical and Acoustic Effects

eg Diaphragm

Gravity Balance

Echo Sounder

Friction Effects

(eg Friction

Calorimeter)

Coolings Effects

(eg Thermal Flow

Meters)

Piezoeletricity

Peizoresistivity

Resistive Capacitive

and Inductive Effects

Magnetomechanical Effects eg Piezomagnetic

Effect

Photoelastic Systems

(Stress-induced

Birefringence)

Interferometers

Sagnac Effect

Doppler Effect

Thermal

Thermal Expansion

(Bimetalic Strip Liquid-in-Glass and Gas Thermometers Resonant Frequency)

Radiometer Effect

(Light Mill)

Seebeck Effect

Thermoresistance

Pyroelectricity

Thermal (Johnsen)

Noise

Thermooptical Effects

(eg in Liquid Crystals)

Radiant Emission

Reaction Activation

eg Thermal Dissociation

Electrokinetic and Joule (Resistive) Heating Charge Collectors Biot-Savartrsquos Law Electrooptical Electrolysis

Electrical

Electrokinetic and Electromechanical Effects

eg Piezoelectricity

Electrometer

Amperersquos Law

Joule (Resistive) Heating

Peltier Effect

Charge Collectors

Langmuir Probe

Biot-Savartrsquos Law Electrooptical Effects

eg Kerr Effect

Pockels Effect

Electroluminescence

Electrolysis

Electromigration

Magnetic

Magnetomechanical Effects

eg Magnetostriction

Magnetometer

Thermomagnetic Effects

eg Righi-Leduc Effect

Galvanomagnetic Effect

eg Ettingshausen Effect

Thermomagnetic Effects eg Ettingshausen-Nernst Effect

Galvanomagnetic Effects

eg Hall Effects

Magnetoresistance

Magnetooptical Effects

Faraday Effect

Cotton-Mouton

Effect

Radiant

Radiation Pressure Bolometer

Thermopile

Photoelectric Effects

eg Photovoltaic Effect

Photoconductive Effect

Phtorefractive Effects

Optical Bistability

Photosynthesis

-dissociation

Chemical

Hygrometer

Electrodeposition Cell

Photoacoustic Effect

Calorimeter

Thermal Conductivity

Cell

Potentiometry Conductimetry

Amperometry

Flame Ionization

Volta Effect

Gas Sensitive Field Effect

Nuclear Magnetic

Resonance

(Emission and Absorp-tion)

Spectroscopy

Chemiluminescence

Quantities to be measured

Transfercharacteristics

Measured quantity

TempForce

Linearity

Important Sensor Variables

ForceTorquePHLight intensityCurrentVoltageMagnetic FieldElectric Field

LinearityResolution Noise Measuring rangeFrequency range (dynamic response)

ChargeVoltageCurrent

FrequencyPhase

Response Curves of the Sensors

Trends in Sensor Development

MEMS based sensorsBio-sensorsSmart and intelligent sensors Sensors for networkingSensors for home automation

Sensor in Automobiles

Definition of Magnetic Sensor

Sensors which are associated with the laws and effects of magnetic and electromagnetic fields

Why are Magnetic Sensors ImportantWhy are Magnetic Sensors Important

1) High reliability Military Flux-gate Search coil

Automobile ABS non-contact angle

Air and space Magnetic torquer Flux-gate

2) High Temperature LVDT Flux-gate

3) High radiation Eddy current probe and LVDT used in nuclear

power plant

Magnetic Effects for SensorsYear Effect Explanation Technical Use

1842 Joule effect Change in shape of a ferromagnetic body with magnetization (magnetostriction)

In combination with piezoelectric elements for magnetometers and potentiometers

1846 ΔE effect Chang in Youngrsquos modulus with magnetization Acoustic delay line components for magnetic field measurement

1847 Matteucci effect Torsion of a ferromagnetic rod in a longitudinal field changes magnetization

Magnetoelastic sensor

1856 Magnetoresistance

(AMR)

Change in resistance with magnetic field Magnetoresistive sensors

1858 Wiedemann effect A torsion is produced in a current carrying ferromagnetic rod when subjected to a longitudinal field

Torque and force measurement

1865 Villari effect Effect on magnetization by tensile or compressive strength

Magnetoelastic sensorsstrength

1879 Hall effect A current carrying crystal produces a transverse voltage when subjected to a magnetic field vertical to its surface

Magnetogalvanic sensors

1903 Skin effect Displacement of current from the interior of material to surface layer due to eddy currents

Distance sensors proximity sensors

1931 Sixtus Tonks effect Pulse magnetization by large Barkhausen jumps Wiegand and pulse-wire sensors

1962 Josephson effect Tunnel effect between two superconducting materials with an extremely thin separating layer quantum effect

SQUID magnetometers

1987 GMR effect Quantum mechanical magnetoresistance effect observed in thin-film structures composed of alternating ferromagnetic and non-magnetic conductive layers

Magnetic field sensor

Sprintonics

1994 GMI effect Large variations that the electrical impedance of some materials exhibits as a function of an external magnetic field

Magnetic field sensor

Principle of search coil type magnetometerPrinciple of search coil type magnetometer

int intint sdotminus=sdotA

ABt

sE d d

dd

Faradayrsquos Induction Law

Faraday 전자기유도법칙

Atd

HAnnU sdotsdotsdotsdot=Φsdotsdot= microωω max0

Voltage output from magnetometer

Sensitivity and Noise of Air Cored Induction Coil

HfDnHAnnU sdotsdotsdotsdotsdot=sdotsdotsdotsdot=Φsdotsdot= 02

2

0max02

microπ

microωω

2

022

00

microπ sdotsdot=

sdot=

Dn

Hf

US

V2π

sdotsdot=

sdotsdot

sdot= minus2

-970

m Hz nT

V10

m A

S V104πmicro

sdot

sdotsdot= minus

Hz nT

V10

2

922

0 DnUπ

Air-cored induction coil in a time-varying magnetic field

sdot

sdotsdot= minus

Hz nT

V10

2

922

0 DnUπ

Air-cored coil output voltage U0 at a magnetic field x frequency product

1 nT middot Hz versus diameter D with number of turns n as parameter

4

22 dDnWW

sdotsdotsdotsdot=

γπ Weight of coil

Coil resistance2

4

d

nDRDC

ρ=

Thermal voltage noisefTRU DCBN ∆= κ4

W

4W

DnfTU BN

sdotsdotsdotsdot∆=

πγρκ

fHnDdTk

DfHW

TkU

UNS

BBN

sdotsdotsdot

=sdotsdotsdot

== 21302

w00 )(28242

σmicroπ

γρmicroπ

Noise voltage

1028

ln286 9minussdot

+minus= αd

DDL

Equivalent circuit diagram of an air-cored induction coil

For single turn loop Dgtgtd

Long single layer solenoid

[H] 10 H][ 10 922

9222

minusminus sdotsdotsdot

=sdotsdotsdot

asympwd

nD

w

nDL

ππ

622

10 101 46

minussdot+sdot

asympwD

nDL

922

10 10 9 3

778 minussdot++sdot

asymphwD

nDL

Short single layer solenoid wgt16D

Multi-layer solenoid Dgtgtwh

( ) 1

370

ndc

DwC r

sdotminussdotsdotsdot

=ε

1

i

2tot minus+=k

C

k

CC

Capacitance C of a coil

Capacitance C of a single-layer coil normalized to

its diameter D versus length-to-diameter ratio wD

of the coil (capacitance C in pF and geometrical

dimensions w and D in cm)

12 minuskk

High permeability core induction coil

Magnetic field pattern around high permeability core

when it is inserted into a homogeneous field It is valid

for low frequencies and if the coil indicated at the middle

of the core is without current

Magnetization of a high permeability core

dt

dnu ci

i Φ

sdotminus= ) ( cosmaxc ci tωsdotΦ=Φ

ci0rc0 maxAHnnU sdotsdotsdotsdot=Φsdotsdot= micromicroωω

HNHHHH )1( minusminus=+= micro

HN

H sdotminus+

=)1(1

1

r

i micro

irdmi HNHHHH )1( minusminus=+= micro

HfAnU sdotsdotsdotsdotsdotsdot= 0cc0 2 micromicroπ

)1(1 r

rc minus+=

micromicro

microN

minus++

minusminus=

infin1)1ln(

11

1 2

22ell mmm

m

mN

10326) (1ln 152

10156) (1ln 262

ell

cyl

++++

=infin

infin

N

N

Induction coil on a cylindrical high permeability core

Demagnetization factorDemagnetization factorN of prolate ellipsoidsand cylindrical rods(descending curves) andcore permeability μc

(ascending curves) ofcylindrical rods versusthe length-to-diameterratio m of the rod withmaterial permeability μr

as parameter

Core permeability μc of cylindrical rods versus thematerial permeability μr with length-to-diameter ratiom of the rod as parameter after

Minimum noise equivalent magnetic field spectral density of an induction coil sensor with high permeability core versus sensor weight Ws (at length-to-diameter ratios m = 50 and 100 permeability μr = 10000 of the core material and f = 1 Hz)

Induction coil sensors with electronic amplifier

II

rKLC

1=ω

II

II

RR

RK

+=

rr

2 i 1

)(

ωω

ωω

ω

D

KF

+

minus

=

+=

II

II

II

2

C

L

R

R

C

L

KD

Frequency responses of the search coil

Frequency responses of thesensitivity SA and the output voltage UA

of an induction coil sensor with a voltageamplifier at a constant magnetic fieldamplitude

Resonance step-up of thesensitivity SA at differentvalues of the damping D

Sensor with transformer coupled negative feedback to the coil

)(i)()(F

0 ωωωω FR

UMUAU A

A sdot

minus=

)( i1

)(

F

0

ωω

ω

FR

MA

FAUU A

sdot+

sdot=

Induction coil connected to a voltage amplifier with

transformer coupled negative feedback to the coil

FR

21

1K0

i1

1

i1

i )(

ωωωωωω

ωω

+sdot

+sdot=

M

RUU A

IIF2 CRL

MAf

sdotsdotsdotsdot

=∆π

Frequency response of the output voltage UA of an induction coil sensor with negative feedback transformer coupled to the coil

Applications of search coil magnetometer

Developed search coil magnetometer using amorphous ribbon

Experimental setup for the effective permeability measurement

Relative permeability depending on the numbers of ribbon(a)

and the air gap between ribbons

Relative permeability depending on the number of ribbons for the different air gap between ribbons

Relative permeability depending on the total number of ribbons for the different air gap between ribbons

10 pT

100 pT

1 pT

Noise spectrum of the developed search coil magnetometer

BJne

E xH

1minus=

neRH

1minus=

22 nP micromicro minus

Hall 효과

Bt

IRU H

HL =

2

22

)( he

eh

Hpne

nPR

micromicromicromicro

+

minus=

Rectangular Hall plate (cc1cc2 current constant sc1sc2

sensor constant I bias current U voltage drop UH Hall

voltage

Physics carrier concentration and kind of carrier measurement

Engineering magnetic field measurement

Current Measurement

Arrangement for noninvasive

current measurement using an iron

core The current to be measured

produces a proportional magnetic

field which can be measured in the

air gap

Characteristic curve produced by

the current

Arrangement for indirect noninvasive

current measurement using the

compensation principle An iron core as

represented in Figure 3-29 is held field

free by injection a current into a

compensating coil wound on the core

which offsets the field generated by the

current being measured The Hall effect

sensor in the air gap serves as a null

indicator

Circuit diagram for AC-power

measurement using a Hall effect

sensor

DC Power Measurement

Circuit diagram for DC-

power measurement using a

Hall effect sensor

Noncontact Position Sensing

Galvanomagnetic components for sensing the position of permanent magnets

and magnetically conductive materials

Current Sensor Based on Hall Sensor

and Magnetic Core for Hybrid Vehicle

KH Yeon1 SD Kim1 and D Son2 1Auto industry co14F Hanshin IT tower Guro Gu Seoul Korea2Hannam UniversityOjung dong 133 Daejeon Rep of Korea

i

Hall sensor

B

I

SB

ring core

B

I10

g

N

Bl S

micro

)( gtgtrmicro

gab core

Current Sensor Based on Hall

Sensor and Magnetic Core

Hall

Effect

Device

CurrentVoltage

applying for

Hall effect device

operation

Output

signals

Magnetic field

Occurred by

current measurement

Signal

process

circuits

Developed Current Sensor

Magnetic core

Hall sensor

PCB

25

30

35

40

45

50

Output voltage V

Current sensor(Open loop type)

Temp 25C

400A model

+400 ~ -400A

SD 000128

Linearity 003

Linearity of the sensor

Characteristics of the Current Sensors

1000A 10 V power supply

-500 -400 -300 -200 -100 0 100 200 300 400 500

00

05

10

15

20

Output voltage V

current A

Temperature 25Linearity 003

Measuring range -400A ~ +400A

1000A Electronic Load

-3

0

3

6

9

12

15

18

dB

Current sensor

DV2 PCB 24pF

40Aturns

Frequency bandwidth

Gain bandwidth 3 MHz

Current 10 A

Temperature 25

Frequency bandwidth 100 kHz

Sensor output voltage vs frequency

at applied current of 40 Aturns

1 10 100

-18

-15

-12

-9

-6

Frequency kHz 측정온도 25

주파수특성 30kHz 이상(3dB 기준)

측정전류 40Aturns(4A 10턴)

측정주파수 100Hz ~ 100kHz

Temperature 25Current 40Aturns

Frequency range 100 Hz ~ 100 kHz

What is Magnetoresistance

Magnetoresistance effect(AMR)

θθθ 2cos2

12sin12cos(

22 minusminus+∆asymp∆ xxxmx hhhRR

32 minusasymp∆ ρρ New effect GMR CMR and GMI

10 ge∆ ρρ

Two bridge configuration for

rotational angle measurement

measurement angle more than 180o

자동차 Engine Management System

Inductive and Eddy Current

Sensors Excited by Permanent Magnets

tNtU dd)( φsdotminus=

construction of an inductive

sensor (courtesy VDO Adolf sensor (courtesy VDO Adolf

Schindling AG)

1) constant socket

2) terminal package

3) permanent magnet

4) cap

5) soft magnetic core

6) coil

7) plate

8) blade connector

γγ

Sensor with yoke Change in the magnetic flux with

varying air gap Continuous lines

minimum air gap dashed lines

maximum air gap

C-shaped sensor

Sensor with radially

magnetized

permanent magnet

Signal Conditioning

Output voltage U of a DC-excited sensor with permanent

magnets when a single iron object passes by

Schematic electrical diagram of an inductive sensor

Linear Variable Differential Transformer

AC-Excited Sensors for Linear Movement

Principle of construction of an LVDT

Electrical circuit of an LVDT

tIMtNU dd dd sdotminus=sdotminus= φ

tIMtIMUUU dd dd 1212 sdotminussdot=minus=

tIMMU dd)( 12 sdotminus=

)(12 xMMMM =minus=

tIxMU dd)( sdot= tI

UxM

dd)( =

Signal Conditioning

power supply

carrier gen

autoampcontrol

LVDTcarrieramp

demod-ulator

phase

shifter

power supply

carrier gen

passivedemod-ulator

LVDTDCamp

Block diagram of a carrier amplifier system

Block diagram of a DC amplifier system

Variable Inductive Sensors

Principle of construction

of the VLP sensor

Principle of a bridge

circuit

lANL r 20 sdotsdotsdot= micromicro

21 BA UUU minus=

21)i(ii( 211 minus+sdot= LLLUU BA ωωω

)21))()((( minus∆minus+∆+∆+sdot= LLLLLLUU BA

)212)(( minus∆+sdot= LLLUU )212)(( minus∆+sdot= LLLUU BA

LLUU BA 21 ∆sdotsdot=

llLL ∆sdot=∆ d d

llLLUU BA ∆sdotsdot= d d)2(1

Applications and Properties

Principle of a construction of a force transducer

(courtesy Hottinger Baldwin Messtechnik)

Vibrationacceleration sensor

Signal Conditioning

Schematic electrical diagram of a force transducer connected with an

amplifier (courtesy Hottinger Baldwin Messtechnik GmbH)

Variable Gap Sensors

)( FeFe2

0 LLllANL micromicromicro +sdotsdot=

FeFe2

0max lANL sdotsdotsdot= micromicro

Construction of a variable gap sensor

Characteristic of a variable gap sensor

Construction of a differential

cross-anchor sensor

Output voltage U versus core

position x plusmn a limits of the

linear rage

Applications of differential cross-anchor sensors

AC-excited Sensors for Rotary Movements

Principle of construction of a synchro

α cos10 sdotsdot= UKU y

)120-( cos10 degsdotsdot= αUKU z

)240-( cos10 degsdotsdot= αUKU x

)120-( sin3100 degsdotsdotsdot=minus= αKUUUU yxyx

)240-( sin3100 degsdotsdotsdot=minus= αKUUUU zyzy

α sin3100 sdotsdotsdot=minus= KUUUU xzxz

Application to the Torque Sensor

Principle of construction of a torque-type synchro

Torque versus angular

difference

)( sin~ rt αα minussdotKM

)( cos~ rt1r αα minussdotUU

Principle of construction of a control-type sensor

Output voltage versus

angular difference

Principle of construction of a differential sychro

Eddy Current Sensors

tBE dd curl minus=JH = curl

0 div =BH(H)B sdot= micro

E(E)J sdot= σ

A B curl= A B curl=

tdd- A E =

)dd( tAJ minus= σ

tdd curl curl AA σmicro minus=

AA) σωmicro iminus= curl )(curl(1

AA) σωmicro i=∆)((1

Eddy Current Tachometer

Construction of a speedometer (courtesy VDO Adolf Schinding AG) 1) spindle 2) bearing

3) holding spring 4) iron yoke 5) eddy current cup 6) shaft of the magnet 7) support of

the magnet 8) temperature compensation 9) permanent magnet 10) torsion spring

Proximity Sensors

Schematic diagram of a proximity sensor

Output current of a proximity switch versus distance

Inductive Flowmeters

)( Btimessdot= υqF

EqF sdot=BE times=υ

)(ds Btimes== υEU )(ds Btimes== υEU

)( Bd timessdot= υU

Bsdotsdotsdot= υdKU

Development of magnetic phase detection

sensor for steam generator tube

Dirac Son1 Kwan-Sang Ryu2 Duck-Gun Park3

1Hannam University Daejeon Rep of Korea2Korea Research Institute of Standards and Science Daejeon Rep of Korea3KoreaAtomic Energy Research Institute Daejeon Rep of Korea

Introduction

The layout of pressurized water reactor (PWR) components

Primary side Secondary side (non-radioactive side)(radioactive side)

The Structure of SG(Steam Generator)(degradation mechanism)

Secondary SidePrimary Side

SCC

A B

A-B

Steam outlet

Anti-vibration

SCC

Fretting

Wall thinning

IGA

U-bend

In commercial power plants SG- height up to 21 m - weight up to 800 tons - 2~4 sets of SG were installed - SG can contain from 3000 to

16000 tubes each about 20 mmin diameter

Primary coolant outlet Primary coolant inlet

Anti-vibrationbars

Tubesupportplate

Tubesheet

IGA

SCC

Pitting

SCC

Inside Tubesheet

Top of Tubesheet

by SSHwang of KAERI

Denting

Sludge pile

in diameter

The SGT is made of nickel basedInconel alloy which is composed of 75 Ni 165Cr and 815Fe

-Degradation mechanism corrosion pitting denting inter granular attack

-Inspection Eddy current Testing(ECT)

Permeability Variation Clusters (PVC)

(Ferro-magnetic phase)

-005

000

005

010

015

m (emug)

1-1

-002

000

002

004

006

008

m (emug)

1-2

-1000 -500 0 500 1000

-015

-010

-005

H ( Am )

-1000 -500 0 500 1000

-006

-004

-002

H ( Am )

The hystresis loop in the fragment of PVC parts of Kori-1 retired SG tube

-004

-002

000

002

004

006

M (emug)

Inconel 600 tested at RT

under tensile stress

1 2 3

4 5 6

7 8 9-004

-002

000

002

004

006

M(emug)

Inconel 600 Heat treated at

602 oC under tensile stress

1 2 3

How can we detect magnetic phase

(PVC)selectively from the flaws in SGT

-3000 -2000 -1000 0 1000 2000 3000

-006

H (Oe)

7 8 9

10 11 12

-3000 -2000 -1000 0 1000 2000 3000

-006

-004

H(Oe)

4 5 6

7 8 9

The hysteresis loop of the tensile tested specimen at room temperature (a) and tensile tested at high temperature (b)

The magnetic phase can be created under the high temperature andpressure conditions which is correspond to the stress corrosion crackingin the SG tube in the NPP(Bruemmer SM Charlot LA amp Henager CH (1988) Corrosion 782)

Principle of ECT

If we can separate magnetic phase selectively from the

flaws using magnetic sensor the reliability of EC in SGT

inspection will be greatly enhanced

Structure of the permeability

sensor

Dimension and photograph of U-shape

sensing yoke

Design of Magnetic Sensor for PVC

sensor sensing yoke

Photograph of the completed sensor front side (above) and rear side (bottom)

R11R12

R10

R8

R6

R9

R13

R7

R14

C18

1 n

C17

C20

C21

D2

DIODE

SIN COS

-

+

U-2A

4

13

2

-

+

U-2B

75

6

8

-

+

U-3A

13

2

8

+5VC19

104

+5V

Schematic diagram of the sensor system

Electronic Circuit of Magnetic Sensor

R20

R

R21

R

-

+

U5AD797

3

26

74

U6

D1

S12

GND3

+VCC4VCC5

IN6

-VCC7

S28

C41

R13

R26

R18

R25

R2210 Ω

R16

R14

R17

10 k

R15

R27

R32

R28

R33

R29

R34

5 k

R30

C29

C37

104

C32473

C39473C40

104

C33

104

C21

104C23

104

C25

104

C26

104

C30

104

C31

104

C35

104

C36

104

C27

104

C28

104

C34

104

C38

104

D3

DIODE

L1

1

2

L2

1

2

L3

1

2

4

-

+

U-4A

4

13

2

-

+

U-4B

75

6

8

-

+

U-5A

4

13

2

-

+

U-5B

75

6

8

-

+

U-6A

4

13

2

-

+

U-6B

75

6

8

C22

104

-5V

+5V

+5V

+5V

+5V

+5V

+5V

U7

D1

S12

GND3

+VCC4

VCC5

IN6

-VCC7

S28

+5V

-5V

-5V

-5V

-5V

-5V

-5V

-5V

-5V

R19

R24

R

R23

R

C24

OUT(X)

OUT(Y)

R1

20 kR210 k

R3

20 kR410 k

C1

104

C8

104

REF43

OUT(X)

OUT(Y)

REF43

U2

+Vcc1

CH02

CH13

CH24

CH35

COMM6

SHDN7

Vref8

+Vcc9

GND10

GND11

DOUT12BUSY13DIN14CS15

DIN16

-

+

U-1A

13

2

8

-

+

U-1B

4

75

6

C410 uF

C5104

DOUT

C210uF

C6104

C3104

DCLK

C7104

DIN

C10

01uF

CS

BUSY

C14 10uF

J1

CON6

123456

D1

DIODE

R5

47K

C9

10uF

C1310uF

Y1

OSC

OUT3

GND2

VCC4

U3

RSTVPP1

GND10

VCC20

XTAL15

XTAL24

P10AIN012P11AIN113P1214P1315P1416P1517P1618P1719

P30RXD2

P31TXD3

P32INT06

P33INT17

P34T08

P35T19

P3711

U4

C1+1

C1-3

C2+4

C2-5

VCC16

GND15

V+2

V-6

R1OUT12

R2OUT9

T1IN11

T2IN10

R1IN13

R2IN8

T1OUT14

T2OUT7

C12 10uF

C16

01uF

C15 10uF

C11

01uF

-5V

+5V

+5V

+5V

+5V

+5V

+5V

+5V

RST

OSC

OSC

RST

DCLKCSDINBUSYDOUT

U1

IN2

GND

4

OUT6

TEMP3

TRIM5

-5V

+5V

Electronic circuit diagram of the magnetic sensor

Photograph of the completed measuring system data acquisition

software in PC and probe scanning system

Experimental Setup for Magnetic Sensor

Reference material Scanning System Software LabVIEW

Reference Material (1) Normal defects and PVCs

Longitudinal and transverse defects

Def W L D Remarks

1 02 500 0213 (20 ) Inner defects

2 02 500 0427 (40 )

3 02 500 0213 (20 )Outer defectsPVC(1018)4 02 500 0427 (40 )

5 02 500 0639 (60 )

6 02 500 0852 (80 )

7 02 500 0639 (60 ) Inner defects

8 02 500 0852 (80 )

- 1 and 2 are inner defects

- 345 and 6 are outer defects with PVC

- 7 and 8 are inner defects

PVC

PVC

Defect Defect

For longitudinal defects and PVC For circumferential defects and PVC

ECT is very difficult to detect circumferential defects

We can distinguish PVCs and defects and longitudinal and circumferential defects

Flux-gate Magnetometer

One core sensor Two core sensor

3-축 flux-gate Magnetometer의 계략도

Sensorpia Co

pro

cess

or(

AV

R)

Sensor 1

RS422

Interface

Mic

ro-p

roce

ssor(

AV

R)

Sensor 2

Sensor 3

Interface

조립된 마그네토미터의 사진

Sensorpia Co

Analog PCB

Digital PCB

Sensorpia Co선형도(linearity)

10

20

30

40

50

60

y-axis

Magnetometer Output (microT)

-60 -50 -40 -30 -20 -10 0 10 20 30 40 50 60

-60

-50

-40

-30

-20

-10

0

10

Y-axis y=099946 x+0015STD 106E-4

Magnetometer Output (

Applied Magnetic Field (microT)

마그네토미터의 noise 특성 Sensorpia Co

1

10

100

y-axis

Magnetometer noise (nT)

0 1 2 3 4 5 6

1E-4

1E-3

001

01

Magnetometer noise (nT)

Frequency (Hz)

Magnetometer for KoDSAT

-150 -100 -50 0 50 100 150

-15

-10

-5

0

5

10

15

Magnetic Moment (Am

2)

Current (mA)

After Thermal Cycle Test

Measured

Resistance 193 ohm

Photograph of Magnetic torquer

Photograph of KoDSAT

Photograph of

3-axis Fluxgate

Magnetometer

Photograph of Magnetic torquer

Application of magnetometer

Moon magnetic fieldmeasurement

Telescope with direction indication

Joule Effect (Magnetostriction)

ϕ2cosel

l=

∆

0=∆

+∆

+∆

b

b

a

a

l

l

Actuator using Terfenol-D

00

05

10

B (T)

800

1000

1200

1400

1600

Magnetostriction (ppm)

-100 -50 0 50 100

-10

-05

00

B (T)

H (kAm)

2 MPa

4 MPa

6 MPa

8 MPa

10 MPa

12 MPa

-100 -50 0 50 100

-200

0

200

400

600

Magnetostriction (ppm)

H (kAm)

2 MPa

4 MPa

6 MPa

8 MPa

10 MPa

12 MPa

600

700

800

900

1000

-4 -3 -2 -1 0 1 2 3 4

0

10

20

30

40

50

60

Displacement (m

icro meter)

I (A)

FIELD

9 kAm

12 kAm

16 kAm

20 kAm

24 kAm

38 kAm

-50 -40 -30 -20 -10 0 10 20 30 40 50

-100

0

100

200

300

400

500

L (PPM)

H (kAm)

9 kAm

12 kAm

16 kAm

20 kAm

24 kAm

38 kAm

Magnetostrictive displacement sensor

Hysteresis loops under

tensile stress σ

(a) Crystalline 68 NiFe

λs = +25 10-6

(b) crystalline pure Ni λs

= -35 10-6

Villari Effect ( Inverse of Joule Effect)

= -35 10-6

(c) amorphous Co-based

alloy

λs = -35 10-6

ϕσλ 2sin2

3sdotsdot= smeE

γ

Permeability depending on the stress

σλmicromicro

1

3

2

Y

J

so

s

r =

γ

Calculated magnetization curves under stress

Variation of magnetization curve by an applied

tensile force (Co-based amorphous alloy)

Alloy Requirement

Materials for magnetoelastic sensors

Why amorphous magnetic materials are important

Stress-strain curves of several materials

Coercivity and hardness of several materials

Principles of magnetoelastic sensors

Non-contact torque sensor

Principle of cross torductor torque

sensor and flux pattern of sensor

poles on the surface of a shaft

a) without and b)with torsional load

Equivalent magnetic circuit of

cross type torque sensor

Helices of principal tensile and compressive stress on the surface of

a shaft subjected to torsion [32] Correlated changes of permeability

are detected by four-branch yoke system with sensing coils 123

and 4 and a common excitation pole

Examples of torque sensors

Four-branch type torque sensor

heads Pole structures realized

by commercial multi-pole

ferrites 14 and 18 min in

diameter (diameter of sensor

h e a d 1 7 a n d 2 4 m m

respectively) respectively)

Principle of Ring Torductor torque transducer

(a b) Physical structure (c) evolution of the

shaft surface under the transducer poles A and BRing torductor for measuring

torque on ship propeller shafts

(shaft diameter ca 500 mm)

(Courtesy ASEA Brown

Boveri AG)

Principal designs of coaxial torque sensors

Schematic diagram of data processing

electronics of a torque sensor

Extensometer (a) Construction of strain sensing element using

amorphous ribbon wound core (b) configuration of lumped

windings

∆E effect of an amorphous FeNi-based

alloy (Fe40 Ni38 Mo4 B18) Hs saturation

field

Magnetically tunable delay line

Torque Sensors using Amorphous wire

Sixtus tonk효과(large Barkhausen효과)

Hysteresis loops of a Wiegand wire for different reset fields

Curie 온도 및Hopkinson효과

Relation between normalised

saturation polarisation and

normalised Curie temperature

Permeability of a Mn-Zn ferrite as

a function of temperature and field

strength

Conclusions

1) Magnetic sensor 는 자동차 공장자동화 항공우주 및 군사용으로많이 사용되고 있다

2) 새로운 소재개발은 자기센서의 성능개발에 직접적인 영향을 준다2) 새로운 소재개발은 자기센서의 성능개발에 직접적인 영향을 준다

3) 센서의 개발을 위해서는 다양한 전공지식이 요구된다

(물리학 재료공학 기계공학 전자공학)

4) 센서분야가 고부가가치를 창출하는 부품사업이다

5) 핵심부품을 생산하는 중소기업의 item으로도 적절하다

Quantitiesto be

measured

Transduceror

Sensor

(Mostly)ElectricalQuantity

What is sensor

INTRODUCTION OF SENSORS

Quantitiesto be

measured

Transduceror

Sensor

ADC amp Embeddedcontroller

Computer

Why are sensors important

Real World

Computerand

Network

Sensor

(smart phone)

Traditionally sensors are used for research and production

World market of sensors

West European market of sensorsWest European market of sensors

Sensor VariablesSecondary

Signal

Primary

Signal

Mechanical Thermal Electrical Magnetic Radiant Chemical

Mechanical

(Fluid) Mechanical and Acoustic Effects

eg Diaphragm

Gravity Balance

Echo Sounder

Friction Effects

(eg Friction

Calorimeter)

Coolings Effects

(eg Thermal Flow

Meters)

Piezoeletricity

Peizoresistivity

Resistive Capacitive

and Inductive Effects

Magnetomechanical Effects eg Piezomagnetic

Effect

Photoelastic Systems

(Stress-induced

Birefringence)

Interferometers

Sagnac Effect

Doppler Effect

Thermal

Thermal Expansion

(Bimetalic Strip Liquid-in-Glass and Gas Thermometers Resonant Frequency)

Radiometer Effect

(Light Mill)

Seebeck Effect

Thermoresistance

Pyroelectricity

Thermal (Johnsen)

Noise

Thermooptical Effects

(eg in Liquid Crystals)

Radiant Emission

Reaction Activation

eg Thermal Dissociation

Electrokinetic and Joule (Resistive) Heating Charge Collectors Biot-Savartrsquos Law Electrooptical Electrolysis

Electrical

Electrokinetic and Electromechanical Effects

eg Piezoelectricity

Electrometer

Amperersquos Law

Joule (Resistive) Heating

Peltier Effect

Charge Collectors

Langmuir Probe

Biot-Savartrsquos Law Electrooptical Effects

eg Kerr Effect

Pockels Effect

Electroluminescence

Electrolysis

Electromigration

Magnetic

Magnetomechanical Effects

eg Magnetostriction

Magnetometer

Thermomagnetic Effects

eg Righi-Leduc Effect

Galvanomagnetic Effect

eg Ettingshausen Effect

Thermomagnetic Effects eg Ettingshausen-Nernst Effect

Galvanomagnetic Effects

eg Hall Effects

Magnetoresistance

Magnetooptical Effects

Faraday Effect

Cotton-Mouton

Effect

Radiant

Radiation Pressure Bolometer

Thermopile

Photoelectric Effects

eg Photovoltaic Effect

Photoconductive Effect

Phtorefractive Effects

Optical Bistability

Photosynthesis

-dissociation

Chemical

Hygrometer

Electrodeposition Cell

Photoacoustic Effect

Calorimeter

Thermal Conductivity

Cell

Potentiometry Conductimetry

Amperometry

Flame Ionization

Volta Effect

Gas Sensitive Field Effect

Nuclear Magnetic

Resonance

(Emission and Absorp-tion)

Spectroscopy

Chemiluminescence

Quantities to be measured

Transfercharacteristics

Measured quantity

TempForce

Linearity

Important Sensor Variables

ForceTorquePHLight intensityCurrentVoltageMagnetic FieldElectric Field

LinearityResolution Noise Measuring rangeFrequency range (dynamic response)

ChargeVoltageCurrent

FrequencyPhase

Response Curves of the Sensors

Trends in Sensor Development

MEMS based sensorsBio-sensorsSmart and intelligent sensors Sensors for networkingSensors for home automation

Sensor in Automobiles

Definition of Magnetic Sensor

Sensors which are associated with the laws and effects of magnetic and electromagnetic fields

Why are Magnetic Sensors ImportantWhy are Magnetic Sensors Important

1) High reliability Military Flux-gate Search coil

Automobile ABS non-contact angle

Air and space Magnetic torquer Flux-gate

2) High Temperature LVDT Flux-gate

3) High radiation Eddy current probe and LVDT used in nuclear

power plant

Magnetic Effects for SensorsYear Effect Explanation Technical Use

1842 Joule effect Change in shape of a ferromagnetic body with magnetization (magnetostriction)

In combination with piezoelectric elements for magnetometers and potentiometers

1846 ΔE effect Chang in Youngrsquos modulus with magnetization Acoustic delay line components for magnetic field measurement

1847 Matteucci effect Torsion of a ferromagnetic rod in a longitudinal field changes magnetization

Magnetoelastic sensor

1856 Magnetoresistance

(AMR)

Change in resistance with magnetic field Magnetoresistive sensors

1858 Wiedemann effect A torsion is produced in a current carrying ferromagnetic rod when subjected to a longitudinal field

Torque and force measurement

1865 Villari effect Effect on magnetization by tensile or compressive strength

Magnetoelastic sensorsstrength

1879 Hall effect A current carrying crystal produces a transverse voltage when subjected to a magnetic field vertical to its surface

Magnetogalvanic sensors

1903 Skin effect Displacement of current from the interior of material to surface layer due to eddy currents

Distance sensors proximity sensors

1931 Sixtus Tonks effect Pulse magnetization by large Barkhausen jumps Wiegand and pulse-wire sensors

1962 Josephson effect Tunnel effect between two superconducting materials with an extremely thin separating layer quantum effect

SQUID magnetometers

1987 GMR effect Quantum mechanical magnetoresistance effect observed in thin-film structures composed of alternating ferromagnetic and non-magnetic conductive layers

Magnetic field sensor

Sprintonics

1994 GMI effect Large variations that the electrical impedance of some materials exhibits as a function of an external magnetic field

Magnetic field sensor

Principle of search coil type magnetometerPrinciple of search coil type magnetometer

int intint sdotminus=sdotA

ABt

sE d d

dd

Faradayrsquos Induction Law

Faraday 전자기유도법칙

Atd

HAnnU sdotsdotsdotsdot=Φsdotsdot= microωω max0

Voltage output from magnetometer

Sensitivity and Noise of Air Cored Induction Coil

HfDnHAnnU sdotsdotsdotsdotsdot=sdotsdotsdotsdot=Φsdotsdot= 02

2

0max02

microπ

microωω

2

022

00

microπ sdotsdot=

sdot=

Dn

Hf

US

V2π

sdotsdot=

sdotsdot

sdot= minus2

-970

m Hz nT

V10

m A

S V104πmicro

sdot

sdotsdot= minus

Hz nT

V10

2

922

0 DnUπ

Air-cored induction coil in a time-varying magnetic field

sdot

sdotsdot= minus

Hz nT

V10

2

922

0 DnUπ

Air-cored coil output voltage U0 at a magnetic field x frequency product

1 nT middot Hz versus diameter D with number of turns n as parameter

4

22 dDnWW

sdotsdotsdotsdot=

γπ Weight of coil

Coil resistance2

4

d

nDRDC

ρ=

Thermal voltage noisefTRU DCBN ∆= κ4

W

4W

DnfTU BN

sdotsdotsdotsdot∆=

πγρκ

fHnDdTk

DfHW

TkU

UNS

BBN

sdotsdotsdot

=sdotsdotsdot

== 21302

w00 )(28242

σmicroπ

γρmicroπ

Noise voltage

1028

ln286 9minussdot

+minus= αd

DDL

Equivalent circuit diagram of an air-cored induction coil

For single turn loop Dgtgtd

Long single layer solenoid

[H] 10 H][ 10 922

9222

minusminus sdotsdotsdot

=sdotsdotsdot

asympwd

nD

w

nDL

ππ

622

10 101 46

minussdot+sdot

asympwD

nDL

922

10 10 9 3

778 minussdot++sdot

asymphwD

nDL

Short single layer solenoid wgt16D

Multi-layer solenoid Dgtgtwh

( ) 1

370

ndc

DwC r

sdotminussdotsdotsdot

=ε

1

i

2tot minus+=k

C

k

CC

Capacitance C of a coil

Capacitance C of a single-layer coil normalized to

its diameter D versus length-to-diameter ratio wD

of the coil (capacitance C in pF and geometrical

dimensions w and D in cm)

12 minuskk

High permeability core induction coil

Magnetic field pattern around high permeability core

when it is inserted into a homogeneous field It is valid

for low frequencies and if the coil indicated at the middle

of the core is without current

Magnetization of a high permeability core

dt

dnu ci

i Φ

sdotminus= ) ( cosmaxc ci tωsdotΦ=Φ

ci0rc0 maxAHnnU sdotsdotsdotsdot=Φsdotsdot= micromicroωω

HNHHHH )1( minusminus=+= micro

HN

H sdotminus+

=)1(1

1

r

i micro

irdmi HNHHHH )1( minusminus=+= micro

HfAnU sdotsdotsdotsdotsdotsdot= 0cc0 2 micromicroπ

)1(1 r

rc minus+=

micromicro

microN

minus++

minusminus=

infin1)1ln(

11

1 2

22ell mmm

m

mN

10326) (1ln 152

10156) (1ln 262

ell

cyl

++++

=infin

infin

N

N

Induction coil on a cylindrical high permeability core

Demagnetization factorDemagnetization factorN of prolate ellipsoidsand cylindrical rods(descending curves) andcore permeability μc

(ascending curves) ofcylindrical rods versusthe length-to-diameterratio m of the rod withmaterial permeability μr

as parameter

Core permeability μc of cylindrical rods versus thematerial permeability μr with length-to-diameter ratiom of the rod as parameter after

Minimum noise equivalent magnetic field spectral density of an induction coil sensor with high permeability core versus sensor weight Ws (at length-to-diameter ratios m = 50 and 100 permeability μr = 10000 of the core material and f = 1 Hz)

Induction coil sensors with electronic amplifier

II

rKLC

1=ω

II

II

RR

RK

+=

rr

2 i 1

)(

ωω

ωω

ω

D

KF

+

minus

=

+=

II

II

II

2

C

L

R

R

C

L

KD

Frequency responses of the search coil

Frequency responses of thesensitivity SA and the output voltage UA

of an induction coil sensor with a voltageamplifier at a constant magnetic fieldamplitude

Resonance step-up of thesensitivity SA at differentvalues of the damping D

Sensor with transformer coupled negative feedback to the coil

)(i)()(F

0 ωωωω FR

UMUAU A

A sdot

minus=

)( i1

)(

F

0

ωω

ω

FR

MA

FAUU A

sdot+

sdot=

Induction coil connected to a voltage amplifier with

transformer coupled negative feedback to the coil

FR

21

1K0

i1

1

i1

i )(

ωωωωωω

ωω

+sdot

+sdot=

M

RUU A

IIF2 CRL

MAf

sdotsdotsdotsdot

=∆π

Frequency response of the output voltage UA of an induction coil sensor with negative feedback transformer coupled to the coil

Applications of search coil magnetometer

Developed search coil magnetometer using amorphous ribbon

Experimental setup for the effective permeability measurement

Relative permeability depending on the numbers of ribbon(a)

and the air gap between ribbons

Relative permeability depending on the number of ribbons for the different air gap between ribbons

Relative permeability depending on the total number of ribbons for the different air gap between ribbons

10 pT

100 pT

1 pT

Noise spectrum of the developed search coil magnetometer

BJne

E xH

1minus=

neRH

1minus=

22 nP micromicro minus

Hall 효과

Bt

IRU H

HL =

2

22

)( he

eh

Hpne

nPR

micromicromicromicro

+

minus=

Rectangular Hall plate (cc1cc2 current constant sc1sc2

sensor constant I bias current U voltage drop UH Hall

voltage

Physics carrier concentration and kind of carrier measurement

Engineering magnetic field measurement

Current Measurement

Arrangement for noninvasive

current measurement using an iron

core The current to be measured

produces a proportional magnetic

field which can be measured in the

air gap

Characteristic curve produced by

the current

Arrangement for indirect noninvasive

current measurement using the

compensation principle An iron core as

represented in Figure 3-29 is held field

free by injection a current into a

compensating coil wound on the core

which offsets the field generated by the

current being measured The Hall effect

sensor in the air gap serves as a null

indicator

Circuit diagram for AC-power

measurement using a Hall effect

sensor

DC Power Measurement

Circuit diagram for DC-

power measurement using a

Hall effect sensor

Noncontact Position Sensing

Galvanomagnetic components for sensing the position of permanent magnets

and magnetically conductive materials

Current Sensor Based on Hall Sensor

and Magnetic Core for Hybrid Vehicle

KH Yeon1 SD Kim1 and D Son2 1Auto industry co14F Hanshin IT tower Guro Gu Seoul Korea2Hannam UniversityOjung dong 133 Daejeon Rep of Korea

i

Hall sensor

B

I

SB

ring core

B

I10

g

N

Bl S

micro

)( gtgtrmicro

gab core

Current Sensor Based on Hall

Sensor and Magnetic Core

Hall

Effect

Device

CurrentVoltage

applying for

Hall effect device

operation

Output

signals

Magnetic field

Occurred by

current measurement

Signal

process

circuits

Developed Current Sensor

Magnetic core

Hall sensor

PCB

25

30

35

40

45

50

Output voltage V

Current sensor(Open loop type)

Temp 25C

400A model

+400 ~ -400A

SD 000128

Linearity 003

Linearity of the sensor

Characteristics of the Current Sensors

1000A 10 V power supply

-500 -400 -300 -200 -100 0 100 200 300 400 500

00

05

10

15

20

Output voltage V

current A

Temperature 25Linearity 003

Measuring range -400A ~ +400A

1000A Electronic Load

-3

0

3

6

9

12

15

18

dB

Current sensor

DV2 PCB 24pF

40Aturns

Frequency bandwidth

Gain bandwidth 3 MHz

Current 10 A

Temperature 25

Frequency bandwidth 100 kHz

Sensor output voltage vs frequency

at applied current of 40 Aturns

1 10 100

-18

-15

-12

-9

-6

Frequency kHz 측정온도 25

주파수특성 30kHz 이상(3dB 기준)

측정전류 40Aturns(4A 10턴)

측정주파수 100Hz ~ 100kHz

Temperature 25Current 40Aturns

Frequency range 100 Hz ~ 100 kHz

What is Magnetoresistance

Magnetoresistance effect(AMR)

θθθ 2cos2

12sin12cos(

22 minusminus+∆asymp∆ xxxmx hhhRR

32 minusasymp∆ ρρ New effect GMR CMR and GMI

10 ge∆ ρρ

Two bridge configuration for

rotational angle measurement

measurement angle more than 180o

자동차 Engine Management System

Inductive and Eddy Current

Sensors Excited by Permanent Magnets

tNtU dd)( φsdotminus=

construction of an inductive

sensor (courtesy VDO Adolf sensor (courtesy VDO Adolf

Schindling AG)

1) constant socket

2) terminal package

3) permanent magnet

4) cap

5) soft magnetic core

6) coil

7) plate

8) blade connector

γγ

Sensor with yoke Change in the magnetic flux with

varying air gap Continuous lines

minimum air gap dashed lines

maximum air gap

C-shaped sensor

Sensor with radially

magnetized

permanent magnet

Signal Conditioning

Output voltage U of a DC-excited sensor with permanent

magnets when a single iron object passes by

Schematic electrical diagram of an inductive sensor

Linear Variable Differential Transformer

AC-Excited Sensors for Linear Movement

Principle of construction of an LVDT

Electrical circuit of an LVDT

tIMtNU dd dd sdotminus=sdotminus= φ

tIMtIMUUU dd dd 1212 sdotminussdot=minus=

tIMMU dd)( 12 sdotminus=

)(12 xMMMM =minus=

tIxMU dd)( sdot= tI

UxM

dd)( =

Signal Conditioning

power supply

carrier gen

autoampcontrol

LVDTcarrieramp

demod-ulator

phase

shifter

power supply

carrier gen

passivedemod-ulator

LVDTDCamp

Block diagram of a carrier amplifier system

Block diagram of a DC amplifier system

Variable Inductive Sensors

Principle of construction

of the VLP sensor

Principle of a bridge

circuit

lANL r 20 sdotsdotsdot= micromicro

21 BA UUU minus=

21)i(ii( 211 minus+sdot= LLLUU BA ωωω

)21))()((( minus∆minus+∆+∆+sdot= LLLLLLUU BA

)212)(( minus∆+sdot= LLLUU )212)(( minus∆+sdot= LLLUU BA

LLUU BA 21 ∆sdotsdot=

llLL ∆sdot=∆ d d

llLLUU BA ∆sdotsdot= d d)2(1

Applications and Properties

Principle of a construction of a force transducer

(courtesy Hottinger Baldwin Messtechnik)

Vibrationacceleration sensor

Signal Conditioning

Schematic electrical diagram of a force transducer connected with an

amplifier (courtesy Hottinger Baldwin Messtechnik GmbH)

Variable Gap Sensors

)( FeFe2

0 LLllANL micromicromicro +sdotsdot=

FeFe2

0max lANL sdotsdotsdot= micromicro

Construction of a variable gap sensor

Characteristic of a variable gap sensor

Construction of a differential

cross-anchor sensor

Output voltage U versus core

position x plusmn a limits of the

linear rage

Applications of differential cross-anchor sensors

AC-excited Sensors for Rotary Movements

Principle of construction of a synchro

α cos10 sdotsdot= UKU y

)120-( cos10 degsdotsdot= αUKU z

)240-( cos10 degsdotsdot= αUKU x

)120-( sin3100 degsdotsdotsdot=minus= αKUUUU yxyx

)240-( sin3100 degsdotsdotsdot=minus= αKUUUU zyzy

α sin3100 sdotsdotsdot=minus= KUUUU xzxz

Application to the Torque Sensor

Principle of construction of a torque-type synchro

Torque versus angular

difference

)( sin~ rt αα minussdotKM

)( cos~ rt1r αα minussdotUU

Principle of construction of a control-type sensor

Output voltage versus

angular difference

Principle of construction of a differential sychro

Eddy Current Sensors

tBE dd curl minus=JH = curl

0 div =BH(H)B sdot= micro

E(E)J sdot= σ

A B curl= A B curl=

tdd- A E =

)dd( tAJ minus= σ

tdd curl curl AA σmicro minus=

AA) σωmicro iminus= curl )(curl(1

AA) σωmicro i=∆)((1

Eddy Current Tachometer

Construction of a speedometer (courtesy VDO Adolf Schinding AG) 1) spindle 2) bearing

3) holding spring 4) iron yoke 5) eddy current cup 6) shaft of the magnet 7) support of

the magnet 8) temperature compensation 9) permanent magnet 10) torsion spring

Proximity Sensors

Schematic diagram of a proximity sensor

Output current of a proximity switch versus distance

Inductive Flowmeters

)( Btimessdot= υqF

EqF sdot=BE times=υ

)(ds Btimes== υEU )(ds Btimes== υEU

)( Bd timessdot= υU

Bsdotsdotsdot= υdKU

Development of magnetic phase detection

sensor for steam generator tube

Dirac Son1 Kwan-Sang Ryu2 Duck-Gun Park3

1Hannam University Daejeon Rep of Korea2Korea Research Institute of Standards and Science Daejeon Rep of Korea3KoreaAtomic Energy Research Institute Daejeon Rep of Korea

Introduction

The layout of pressurized water reactor (PWR) components

Primary side Secondary side (non-radioactive side)(radioactive side)

The Structure of SG(Steam Generator)(degradation mechanism)

Secondary SidePrimary Side

SCC

A B

A-B

Steam outlet

Anti-vibration

SCC

Fretting

Wall thinning

IGA

U-bend

In commercial power plants SG- height up to 21 m - weight up to 800 tons - 2~4 sets of SG were installed - SG can contain from 3000 to

16000 tubes each about 20 mmin diameter

Primary coolant outlet Primary coolant inlet

Anti-vibrationbars

Tubesupportplate

Tubesheet

IGA

SCC

Pitting

SCC

Inside Tubesheet

Top of Tubesheet

by SSHwang of KAERI

Denting

Sludge pile

in diameter

The SGT is made of nickel basedInconel alloy which is composed of 75 Ni 165Cr and 815Fe

-Degradation mechanism corrosion pitting denting inter granular attack

-Inspection Eddy current Testing(ECT)

Permeability Variation Clusters (PVC)

(Ferro-magnetic phase)

-005

000

005

010

015

m (emug)

1-1

-002

000

002

004

006

008

m (emug)

1-2

-1000 -500 0 500 1000

-015

-010

-005

H ( Am )

-1000 -500 0 500 1000

-006

-004

-002

H ( Am )

The hystresis loop in the fragment of PVC parts of Kori-1 retired SG tube

-004

-002

000

002

004

006

M (emug)

Inconel 600 tested at RT

under tensile stress

1 2 3

4 5 6

7 8 9-004

-002

000

002

004

006

M(emug)

Inconel 600 Heat treated at

602 oC under tensile stress

1 2 3

How can we detect magnetic phase

(PVC)selectively from the flaws in SGT

-3000 -2000 -1000 0 1000 2000 3000

-006

H (Oe)

7 8 9

10 11 12

-3000 -2000 -1000 0 1000 2000 3000

-006

-004

H(Oe)

4 5 6

7 8 9

The hysteresis loop of the tensile tested specimen at room temperature (a) and tensile tested at high temperature (b)

The magnetic phase can be created under the high temperature andpressure conditions which is correspond to the stress corrosion crackingin the SG tube in the NPP(Bruemmer SM Charlot LA amp Henager CH (1988) Corrosion 782)

Principle of ECT

If we can separate magnetic phase selectively from the

flaws using magnetic sensor the reliability of EC in SGT

inspection will be greatly enhanced

Structure of the permeability

sensor

Dimension and photograph of U-shape

sensing yoke

Design of Magnetic Sensor for PVC

sensor sensing yoke

Photograph of the completed sensor front side (above) and rear side (bottom)

R11R12

R10

R8

R6

R9

R13

R7

R14

C18

1 n

C17

C20

C21

D2

DIODE

SIN COS

-

+

U-2A

4

13

2

-

+

U-2B

75

6

8

-

+

U-3A

13

2

8

+5VC19

104

+5V

Schematic diagram of the sensor system

Electronic Circuit of Magnetic Sensor

R20

R

R21

R

-

+

U5AD797

3

26

74

U6

D1

S12

GND3

+VCC4VCC5

IN6

-VCC7

S28

C41

R13

R26

R18

R25

R2210 Ω

R16

R14

R17

10 k

R15

R27

R32

R28

R33

R29

R34

5 k

R30

C29

C37

104

C32473

C39473C40

104

C33

104

C21

104C23

104

C25

104

C26

104

C30

104

C31

104

C35

104

C36

104

C27

104

C28

104

C34

104

C38

104

D3

DIODE

L1

1

2

L2

1

2

L3

1

2

4

-

+

U-4A

4

13

2

-

+

U-4B

75

6

8

-

+

U-5A

4

13

2

-

+

U-5B

75

6

8

-

+

U-6A

4

13

2

-

+

U-6B

75

6

8

C22

104

-5V

+5V

+5V

+5V

+5V

+5V

+5V

U7

D1

S12

GND3

+VCC4

VCC5

IN6

-VCC7

S28

+5V

-5V

-5V

-5V

-5V

-5V

-5V

-5V

-5V

R19

R24

R

R23

R

C24

OUT(X)

OUT(Y)

R1

20 kR210 k

R3

20 kR410 k

C1

104

C8

104

REF43

OUT(X)

OUT(Y)

REF43

U2

+Vcc1

CH02

CH13

CH24

CH35

COMM6

SHDN7

Vref8

+Vcc9

GND10

GND11

DOUT12BUSY13DIN14CS15

DIN16

-

+

U-1A

13

2

8

-

+

U-1B

4

75

6

C410 uF

C5104

DOUT

C210uF

C6104

C3104

DCLK

C7104

DIN

C10

01uF

CS

BUSY

C14 10uF

J1

CON6

123456

D1

DIODE

R5

47K

C9

10uF

C1310uF

Y1

OSC

OUT3

GND2

VCC4

U3

RSTVPP1

GND10

VCC20

XTAL15

XTAL24

P10AIN012P11AIN113P1214P1315P1416P1517P1618P1719

P30RXD2

P31TXD3

P32INT06

P33INT17

P34T08

P35T19

P3711

U4

C1+1

C1-3

C2+4

C2-5

VCC16

GND15

V+2

V-6

R1OUT12

R2OUT9

T1IN11

T2IN10

R1IN13

R2IN8

T1OUT14

T2OUT7

C12 10uF

C16

01uF

C15 10uF

C11

01uF

-5V

+5V

+5V

+5V

+5V

+5V

+5V

+5V

RST

OSC

OSC

RST

DCLKCSDINBUSYDOUT

U1

IN2

GND

4

OUT6

TEMP3

TRIM5

-5V

+5V

Electronic circuit diagram of the magnetic sensor

Photograph of the completed measuring system data acquisition

software in PC and probe scanning system

Experimental Setup for Magnetic Sensor

Reference material Scanning System Software LabVIEW

Reference Material (1) Normal defects and PVCs

Longitudinal and transverse defects

Def W L D Remarks

1 02 500 0213 (20 ) Inner defects

2 02 500 0427 (40 )

3 02 500 0213 (20 )Outer defectsPVC(1018)4 02 500 0427 (40 )

5 02 500 0639 (60 )

6 02 500 0852 (80 )

7 02 500 0639 (60 ) Inner defects

8 02 500 0852 (80 )

- 1 and 2 are inner defects

- 345 and 6 are outer defects with PVC

- 7 and 8 are inner defects

PVC

PVC

Defect Defect

For longitudinal defects and PVC For circumferential defects and PVC

ECT is very difficult to detect circumferential defects

We can distinguish PVCs and defects and longitudinal and circumferential defects

Flux-gate Magnetometer

One core sensor Two core sensor

3-축 flux-gate Magnetometer의 계략도

Sensorpia Co

pro

cess

or(

AV

R)

Sensor 1

RS422

Interface

Mic

ro-p

roce

ssor(

AV

R)

Sensor 2

Sensor 3

Interface

조립된 마그네토미터의 사진

Sensorpia Co

Analog PCB

Digital PCB

Sensorpia Co선형도(linearity)

10

20

30

40

50

60

y-axis

Magnetometer Output (microT)

-60 -50 -40 -30 -20 -10 0 10 20 30 40 50 60

-60

-50

-40

-30

-20

-10

0

10

Y-axis y=099946 x+0015STD 106E-4

Magnetometer Output (

Applied Magnetic Field (microT)

마그네토미터의 noise 특성 Sensorpia Co

1

10

100

y-axis

Magnetometer noise (nT)

0 1 2 3 4 5 6

1E-4

1E-3

001

01

Magnetometer noise (nT)

Frequency (Hz)

Magnetometer for KoDSAT

-150 -100 -50 0 50 100 150

-15

-10

-5

0

5

10

15

Magnetic Moment (Am

2)

Current (mA)

After Thermal Cycle Test

Measured

Resistance 193 ohm

Photograph of Magnetic torquer

Photograph of KoDSAT

Photograph of

3-axis Fluxgate

Magnetometer

Photograph of Magnetic torquer

Application of magnetometer

Moon magnetic fieldmeasurement

Telescope with direction indication

Joule Effect (Magnetostriction)

ϕ2cosel

l=

∆

0=∆

+∆

+∆

b

b

a

a

l

l

Actuator using Terfenol-D

00

05

10

B (T)

800

1000

1200

1400

1600

Magnetostriction (ppm)

-100 -50 0 50 100

-10

-05

00

B (T)

H (kAm)

2 MPa

4 MPa

6 MPa

8 MPa

10 MPa

12 MPa

-100 -50 0 50 100

-200

0

200

400

600

Magnetostriction (ppm)

H (kAm)

2 MPa

4 MPa

6 MPa

8 MPa

10 MPa

12 MPa

600

700

800

900

1000

-4 -3 -2 -1 0 1 2 3 4

0

10

20

30

40

50

60

Displacement (m

icro meter)

I (A)

FIELD

9 kAm

12 kAm

16 kAm

20 kAm

24 kAm

38 kAm

-50 -40 -30 -20 -10 0 10 20 30 40 50

-100

0

100

200

300

400

500

L (PPM)

H (kAm)

9 kAm

12 kAm

16 kAm

20 kAm

24 kAm

38 kAm

Magnetostrictive displacement sensor

Hysteresis loops under

tensile stress σ

(a) Crystalline 68 NiFe

λs = +25 10-6

(b) crystalline pure Ni λs

= -35 10-6

Villari Effect ( Inverse of Joule Effect)

= -35 10-6

(c) amorphous Co-based

alloy

λs = -35 10-6

ϕσλ 2sin2

3sdotsdot= smeE

γ

Permeability depending on the stress

σλmicromicro

1

3

2

Y

J

so

s

r =

γ

Calculated magnetization curves under stress

Variation of magnetization curve by an applied

tensile force (Co-based amorphous alloy)

Alloy Requirement

Materials for magnetoelastic sensors

Why amorphous magnetic materials are important

Stress-strain curves of several materials

Coercivity and hardness of several materials

Principles of magnetoelastic sensors

Non-contact torque sensor

Principle of cross torductor torque

sensor and flux pattern of sensor

poles on the surface of a shaft

a) without and b)with torsional load

Equivalent magnetic circuit of

cross type torque sensor

Helices of principal tensile and compressive stress on the surface of

a shaft subjected to torsion [32] Correlated changes of permeability

are detected by four-branch yoke system with sensing coils 123

and 4 and a common excitation pole

Examples of torque sensors

Four-branch type torque sensor

heads Pole structures realized

by commercial multi-pole

ferrites 14 and 18 min in

diameter (diameter of sensor

h e a d 1 7 a n d 2 4 m m

respectively) respectively)

Principle of Ring Torductor torque transducer

(a b) Physical structure (c) evolution of the

shaft surface under the transducer poles A and BRing torductor for measuring

torque on ship propeller shafts

(shaft diameter ca 500 mm)

(Courtesy ASEA Brown

Boveri AG)

Principal designs of coaxial torque sensors

Schematic diagram of data processing

electronics of a torque sensor

Extensometer (a) Construction of strain sensing element using

amorphous ribbon wound core (b) configuration of lumped

windings

∆E effect of an amorphous FeNi-based

alloy (Fe40 Ni38 Mo4 B18) Hs saturation

field

Magnetically tunable delay line

Torque Sensors using Amorphous wire

Sixtus tonk효과(large Barkhausen효과)

Hysteresis loops of a Wiegand wire for different reset fields

Curie 온도 및Hopkinson효과

Relation between normalised

saturation polarisation and

normalised Curie temperature

Permeability of a Mn-Zn ferrite as

a function of temperature and field

strength

Conclusions

1) Magnetic sensor 는 자동차 공장자동화 항공우주 및 군사용으로많이 사용되고 있다

2) 새로운 소재개발은 자기센서의 성능개발에 직접적인 영향을 준다2) 새로운 소재개발은 자기센서의 성능개발에 직접적인 영향을 준다

3) 센서의 개발을 위해서는 다양한 전공지식이 요구된다

(물리학 재료공학 기계공학 전자공학)

4) 센서분야가 고부가가치를 창출하는 부품사업이다

5) 핵심부품을 생산하는 중소기업의 item으로도 적절하다

Computer

Why are sensors important

Real World

Computerand

Network

Sensor

(smart phone)

Traditionally sensors are used for research and production

World market of sensors

West European market of sensorsWest European market of sensors

Sensor VariablesSecondary

Signal

Primary

Signal

Mechanical Thermal Electrical Magnetic Radiant Chemical

Mechanical

(Fluid) Mechanical and Acoustic Effects

eg Diaphragm

Gravity Balance

Echo Sounder

Friction Effects

(eg Friction

Calorimeter)

Coolings Effects

(eg Thermal Flow

Meters)

Piezoeletricity

Peizoresistivity

Resistive Capacitive

and Inductive Effects

Magnetomechanical Effects eg Piezomagnetic

Effect

Photoelastic Systems

(Stress-induced

Birefringence)

Interferometers

Sagnac Effect

Doppler Effect

Thermal

Thermal Expansion

(Bimetalic Strip Liquid-in-Glass and Gas Thermometers Resonant Frequency)

Radiometer Effect

(Light Mill)

Seebeck Effect

Thermoresistance

Pyroelectricity

Thermal (Johnsen)

Noise

Thermooptical Effects

(eg in Liquid Crystals)

Radiant Emission

Reaction Activation

eg Thermal Dissociation

Electrokinetic and Joule (Resistive) Heating Charge Collectors Biot-Savartrsquos Law Electrooptical Electrolysis

Electrical

Electrokinetic and Electromechanical Effects

eg Piezoelectricity

Electrometer

Amperersquos Law

Joule (Resistive) Heating

Peltier Effect

Charge Collectors

Langmuir Probe

Biot-Savartrsquos Law Electrooptical Effects

eg Kerr Effect

Pockels Effect

Electroluminescence

Electrolysis

Electromigration

Magnetic

Magnetomechanical Effects

eg Magnetostriction

Magnetometer

Thermomagnetic Effects

eg Righi-Leduc Effect

Galvanomagnetic Effect

eg Ettingshausen Effect

Thermomagnetic Effects eg Ettingshausen-Nernst Effect

Galvanomagnetic Effects

eg Hall Effects

Magnetoresistance

Magnetooptical Effects

Faraday Effect

Cotton-Mouton

Effect

Radiant

Radiation Pressure Bolometer

Thermopile

Photoelectric Effects

eg Photovoltaic Effect

Photoconductive Effect

Phtorefractive Effects

Optical Bistability

Photosynthesis

-dissociation

Chemical

Hygrometer

Electrodeposition Cell

Photoacoustic Effect

Calorimeter

Thermal Conductivity

Cell

Potentiometry Conductimetry

Amperometry

Flame Ionization

Volta Effect

Gas Sensitive Field Effect

Nuclear Magnetic

Resonance

(Emission and Absorp-tion)

Spectroscopy

Chemiluminescence

Quantities to be measured

Transfercharacteristics

Measured quantity

TempForce

Linearity

Important Sensor Variables

ForceTorquePHLight intensityCurrentVoltageMagnetic FieldElectric Field

LinearityResolution Noise Measuring rangeFrequency range (dynamic response)

ChargeVoltageCurrent

FrequencyPhase

Response Curves of the Sensors

Trends in Sensor Development

MEMS based sensorsBio-sensorsSmart and intelligent sensors Sensors for networkingSensors for home automation

Sensor in Automobiles

Definition of Magnetic Sensor

Sensors which are associated with the laws and effects of magnetic and electromagnetic fields

Why are Magnetic Sensors ImportantWhy are Magnetic Sensors Important

1) High reliability Military Flux-gate Search coil

Automobile ABS non-contact angle

Air and space Magnetic torquer Flux-gate

2) High Temperature LVDT Flux-gate

3) High radiation Eddy current probe and LVDT used in nuclear

power plant

Magnetic Effects for SensorsYear Effect Explanation Technical Use

1842 Joule effect Change in shape of a ferromagnetic body with magnetization (magnetostriction)

In combination with piezoelectric elements for magnetometers and potentiometers

1846 ΔE effect Chang in Youngrsquos modulus with magnetization Acoustic delay line components for magnetic field measurement

1847 Matteucci effect Torsion of a ferromagnetic rod in a longitudinal field changes magnetization

Magnetoelastic sensor

1856 Magnetoresistance

(AMR)

Change in resistance with magnetic field Magnetoresistive sensors

1858 Wiedemann effect A torsion is produced in a current carrying ferromagnetic rod when subjected to a longitudinal field

Torque and force measurement

1865 Villari effect Effect on magnetization by tensile or compressive strength

Magnetoelastic sensorsstrength

1879 Hall effect A current carrying crystal produces a transverse voltage when subjected to a magnetic field vertical to its surface

Magnetogalvanic sensors

1903 Skin effect Displacement of current from the interior of material to surface layer due to eddy currents

Distance sensors proximity sensors

1931 Sixtus Tonks effect Pulse magnetization by large Barkhausen jumps Wiegand and pulse-wire sensors

1962 Josephson effect Tunnel effect between two superconducting materials with an extremely thin separating layer quantum effect

SQUID magnetometers

1987 GMR effect Quantum mechanical magnetoresistance effect observed in thin-film structures composed of alternating ferromagnetic and non-magnetic conductive layers

Magnetic field sensor

Sprintonics

1994 GMI effect Large variations that the electrical impedance of some materials exhibits as a function of an external magnetic field

Magnetic field sensor

Principle of search coil type magnetometerPrinciple of search coil type magnetometer

int intint sdotminus=sdotA

ABt

sE d d

dd

Faradayrsquos Induction Law

Faraday 전자기유도법칙

Atd

HAnnU sdotsdotsdotsdot=Φsdotsdot= microωω max0

Voltage output from magnetometer

Sensitivity and Noise of Air Cored Induction Coil

HfDnHAnnU sdotsdotsdotsdotsdot=sdotsdotsdotsdot=Φsdotsdot= 02

2

0max02

microπ

microωω

2

022

00

microπ sdotsdot=

sdot=

Dn

Hf

US

V2π

sdotsdot=

sdotsdot

sdot= minus2

-970

m Hz nT

V10

m A

S V104πmicro

sdot

sdotsdot= minus

Hz nT

V10

2

922

0 DnUπ

Air-cored induction coil in a time-varying magnetic field

sdot

sdotsdot= minus

Hz nT

V10

2

922

0 DnUπ

Air-cored coil output voltage U0 at a magnetic field x frequency product

1 nT middot Hz versus diameter D with number of turns n as parameter

4

22 dDnWW

sdotsdotsdotsdot=

γπ Weight of coil

Coil resistance2

4

d

nDRDC

ρ=

Thermal voltage noisefTRU DCBN ∆= κ4

W

4W

DnfTU BN

sdotsdotsdotsdot∆=

πγρκ

fHnDdTk

DfHW

TkU

UNS

BBN

sdotsdotsdot

=sdotsdotsdot

== 21302

w00 )(28242

σmicroπ

γρmicroπ

Noise voltage

1028

ln286 9minussdot

+minus= αd

DDL

Equivalent circuit diagram of an air-cored induction coil

For single turn loop Dgtgtd

Long single layer solenoid

[H] 10 H][ 10 922

9222

minusminus sdotsdotsdot

=sdotsdotsdot

asympwd

nD

w

nDL

ππ

622

10 101 46

minussdot+sdot

asympwD

nDL

922

10 10 9 3

778 minussdot++sdot

asymphwD

nDL

Short single layer solenoid wgt16D

Multi-layer solenoid Dgtgtwh

( ) 1

370

ndc

DwC r

sdotminussdotsdotsdot

=ε

1

i

2tot minus+=k

C

k

CC

Capacitance C of a coil

Capacitance C of a single-layer coil normalized to

its diameter D versus length-to-diameter ratio wD

of the coil (capacitance C in pF and geometrical

dimensions w and D in cm)

12 minuskk

High permeability core induction coil

Magnetic field pattern around high permeability core

when it is inserted into a homogeneous field It is valid

for low frequencies and if the coil indicated at the middle

of the core is without current

Magnetization of a high permeability core

dt

dnu ci

i Φ

sdotminus= ) ( cosmaxc ci tωsdotΦ=Φ

ci0rc0 maxAHnnU sdotsdotsdotsdot=Φsdotsdot= micromicroωω

HNHHHH )1( minusminus=+= micro

HN

H sdotminus+

=)1(1

1

r

i micro

irdmi HNHHHH )1( minusminus=+= micro

HfAnU sdotsdotsdotsdotsdotsdot= 0cc0 2 micromicroπ

)1(1 r

rc minus+=

micromicro

microN

minus++

minusminus=

infin1)1ln(

11

1 2

22ell mmm

m

mN

10326) (1ln 152

10156) (1ln 262

ell

cyl

++++

=infin

infin

N

N

Induction coil on a cylindrical high permeability core

Demagnetization factorDemagnetization factorN of prolate ellipsoidsand cylindrical rods(descending curves) andcore permeability μc

(ascending curves) ofcylindrical rods versusthe length-to-diameterratio m of the rod withmaterial permeability μr

as parameter

Core permeability μc of cylindrical rods versus thematerial permeability μr with length-to-diameter ratiom of the rod as parameter after

Minimum noise equivalent magnetic field spectral density of an induction coil sensor with high permeability core versus sensor weight Ws (at length-to-diameter ratios m = 50 and 100 permeability μr = 10000 of the core material and f = 1 Hz)

Induction coil sensors with electronic amplifier

II

rKLC

1=ω

II

II

RR

RK

+=

rr

2 i 1

)(

ωω

ωω

ω

D

KF

+

minus

=

+=

II

II

II

2

C

L

R

R

C

L

KD

Frequency responses of the search coil

Frequency responses of thesensitivity SA and the output voltage UA

of an induction coil sensor with a voltageamplifier at a constant magnetic fieldamplitude

Resonance step-up of thesensitivity SA at differentvalues of the damping D

Sensor with transformer coupled negative feedback to the coil

)(i)()(F

0 ωωωω FR

UMUAU A

A sdot

minus=

)( i1

)(

F

0

ωω

ω

FR

MA

FAUU A

sdot+

sdot=

Induction coil connected to a voltage amplifier with

transformer coupled negative feedback to the coil

FR

21

1K0

i1

1

i1

i )(

ωωωωωω

ωω

+sdot

+sdot=

M

RUU A

IIF2 CRL

MAf

sdotsdotsdotsdot

=∆π

Frequency response of the output voltage UA of an induction coil sensor with negative feedback transformer coupled to the coil

Applications of search coil magnetometer

Developed search coil magnetometer using amorphous ribbon

Experimental setup for the effective permeability measurement

Relative permeability depending on the numbers of ribbon(a)

and the air gap between ribbons

Relative permeability depending on the number of ribbons for the different air gap between ribbons

Relative permeability depending on the total number of ribbons for the different air gap between ribbons

10 pT

100 pT

1 pT

Noise spectrum of the developed search coil magnetometer

BJne

E xH

1minus=

neRH

1minus=

22 nP micromicro minus

Hall 효과

Bt

IRU H

HL =

2

22

)( he

eh

Hpne

nPR

micromicromicromicro

+

minus=

Rectangular Hall plate (cc1cc2 current constant sc1sc2

sensor constant I bias current U voltage drop UH Hall

voltage

Physics carrier concentration and kind of carrier measurement

Engineering magnetic field measurement

Current Measurement

Arrangement for noninvasive

current measurement using an iron

core The current to be measured

produces a proportional magnetic

field which can be measured in the

air gap

Characteristic curve produced by

the current

Arrangement for indirect noninvasive

current measurement using the

compensation principle An iron core as

represented in Figure 3-29 is held field

free by injection a current into a

compensating coil wound on the core

which offsets the field generated by the

current being measured The Hall effect

sensor in the air gap serves as a null

indicator

Circuit diagram for AC-power

measurement using a Hall effect

sensor

DC Power Measurement

Circuit diagram for DC-

power measurement using a

Hall effect sensor

Noncontact Position Sensing

Galvanomagnetic components for sensing the position of permanent magnets

and magnetically conductive materials

Current Sensor Based on Hall Sensor

and Magnetic Core for Hybrid Vehicle

KH Yeon1 SD Kim1 and D Son2 1Auto industry co14F Hanshin IT tower Guro Gu Seoul Korea2Hannam UniversityOjung dong 133 Daejeon Rep of Korea

i

Hall sensor

B

I

SB

ring core

B

I10

g

N

Bl S

micro

)( gtgtrmicro

gab core

Current Sensor Based on Hall

Sensor and Magnetic Core

Hall

Effect

Device

CurrentVoltage

applying for

Hall effect device

operation

Output

signals

Magnetic field

Occurred by

current measurement

Signal

process

circuits

Developed Current Sensor

Magnetic core

Hall sensor

PCB

25

30

35

40

45

50

Output voltage V

Current sensor(Open loop type)

Temp 25C

400A model

+400 ~ -400A

SD 000128

Linearity 003

Linearity of the sensor

Characteristics of the Current Sensors

1000A 10 V power supply

-500 -400 -300 -200 -100 0 100 200 300 400 500

00

05

10

15

20

Output voltage V

current A

Temperature 25Linearity 003

Measuring range -400A ~ +400A

1000A Electronic Load

-3

0

3

6

9

12

15

18

dB

Current sensor

DV2 PCB 24pF

40Aturns

Frequency bandwidth

Gain bandwidth 3 MHz

Current 10 A

Temperature 25

Frequency bandwidth 100 kHz

Sensor output voltage vs frequency

at applied current of 40 Aturns

1 10 100

-18

-15

-12

-9

-6

Frequency kHz 측정온도 25

주파수특성 30kHz 이상(3dB 기준)

측정전류 40Aturns(4A 10턴)

측정주파수 100Hz ~ 100kHz

Temperature 25Current 40Aturns

Frequency range 100 Hz ~ 100 kHz

What is Magnetoresistance

Magnetoresistance effect(AMR)

θθθ 2cos2

12sin12cos(

22 minusminus+∆asymp∆ xxxmx hhhRR

32 minusasymp∆ ρρ New effect GMR CMR and GMI

10 ge∆ ρρ

Two bridge configuration for

rotational angle measurement

measurement angle more than 180o

자동차 Engine Management System

Inductive and Eddy Current

Sensors Excited by Permanent Magnets

tNtU dd)( φsdotminus=

construction of an inductive

sensor (courtesy VDO Adolf sensor (courtesy VDO Adolf

Schindling AG)

1) constant socket

2) terminal package

3) permanent magnet

4) cap

5) soft magnetic core

6) coil

7) plate

8) blade connector

γγ

Sensor with yoke Change in the magnetic flux with

varying air gap Continuous lines

minimum air gap dashed lines

maximum air gap

C-shaped sensor

Sensor with radially

magnetized

permanent magnet

Signal Conditioning

Output voltage U of a DC-excited sensor with permanent

magnets when a single iron object passes by

Schematic electrical diagram of an inductive sensor

Linear Variable Differential Transformer

AC-Excited Sensors for Linear Movement

Principle of construction of an LVDT

Electrical circuit of an LVDT

tIMtNU dd dd sdotminus=sdotminus= φ

tIMtIMUUU dd dd 1212 sdotminussdot=minus=

tIMMU dd)( 12 sdotminus=

)(12 xMMMM =minus=

tIxMU dd)( sdot= tI

UxM

dd)( =

Signal Conditioning

power supply

carrier gen

autoampcontrol

LVDTcarrieramp

demod-ulator

phase

shifter

power supply

carrier gen

passivedemod-ulator

LVDTDCamp

Block diagram of a carrier amplifier system

Block diagram of a DC amplifier system

Variable Inductive Sensors

Principle of construction

of the VLP sensor

Principle of a bridge

circuit

lANL r 20 sdotsdotsdot= micromicro

21 BA UUU minus=

21)i(ii( 211 minus+sdot= LLLUU BA ωωω

)21))()((( minus∆minus+∆+∆+sdot= LLLLLLUU BA

)212)(( minus∆+sdot= LLLUU )212)(( minus∆+sdot= LLLUU BA

LLUU BA 21 ∆sdotsdot=

llLL ∆sdot=∆ d d

llLLUU BA ∆sdotsdot= d d)2(1

Applications and Properties

Principle of a construction of a force transducer

(courtesy Hottinger Baldwin Messtechnik)

Vibrationacceleration sensor

Signal Conditioning

Schematic electrical diagram of a force transducer connected with an

amplifier (courtesy Hottinger Baldwin Messtechnik GmbH)

Variable Gap Sensors

)( FeFe2

0 LLllANL micromicromicro +sdotsdot=

FeFe2

0max lANL sdotsdotsdot= micromicro

Construction of a variable gap sensor

Characteristic of a variable gap sensor

Construction of a differential

cross-anchor sensor

Output voltage U versus core

position x plusmn a limits of the

linear rage

Applications of differential cross-anchor sensors

AC-excited Sensors for Rotary Movements

Principle of construction of a synchro

α cos10 sdotsdot= UKU y

)120-( cos10 degsdotsdot= αUKU z

)240-( cos10 degsdotsdot= αUKU x

)120-( sin3100 degsdotsdotsdot=minus= αKUUUU yxyx

)240-( sin3100 degsdotsdotsdot=minus= αKUUUU zyzy

α sin3100 sdotsdotsdot=minus= KUUUU xzxz

Application to the Torque Sensor

Principle of construction of a torque-type synchro

Torque versus angular

difference

)( sin~ rt αα minussdotKM

)( cos~ rt1r αα minussdotUU

Principle of construction of a control-type sensor

Output voltage versus

angular difference

Principle of construction of a differential sychro

Eddy Current Sensors

tBE dd curl minus=JH = curl

0 div =BH(H)B sdot= micro

E(E)J sdot= σ

A B curl= A B curl=

tdd- A E =

)dd( tAJ minus= σ

tdd curl curl AA σmicro minus=

AA) σωmicro iminus= curl )(curl(1

AA) σωmicro i=∆)((1

Eddy Current Tachometer

Construction of a speedometer (courtesy VDO Adolf Schinding AG) 1) spindle 2) bearing

3) holding spring 4) iron yoke 5) eddy current cup 6) shaft of the magnet 7) support of

the magnet 8) temperature compensation 9) permanent magnet 10) torsion spring

Proximity Sensors

Schematic diagram of a proximity sensor

Output current of a proximity switch versus distance

Inductive Flowmeters

)( Btimessdot= υqF

EqF sdot=BE times=υ

)(ds Btimes== υEU )(ds Btimes== υEU

)( Bd timessdot= υU

Bsdotsdotsdot= υdKU

Development of magnetic phase detection

sensor for steam generator tube

Dirac Son1 Kwan-Sang Ryu2 Duck-Gun Park3

1Hannam University Daejeon Rep of Korea2Korea Research Institute of Standards and Science Daejeon Rep of Korea3KoreaAtomic Energy Research Institute Daejeon Rep of Korea

Introduction

The layout of pressurized water reactor (PWR) components

Primary side Secondary side (non-radioactive side)(radioactive side)

The Structure of SG(Steam Generator)(degradation mechanism)

Secondary SidePrimary Side

SCC

A B

A-B

Steam outlet

Anti-vibration

SCC

Fretting

Wall thinning

IGA

U-bend

In commercial power plants SG- height up to 21 m - weight up to 800 tons - 2~4 sets of SG were installed - SG can contain from 3000 to

16000 tubes each about 20 mmin diameter

Primary coolant outlet Primary coolant inlet

Anti-vibrationbars

Tubesupportplate

Tubesheet

IGA

SCC

Pitting

SCC

Inside Tubesheet

Top of Tubesheet

by SSHwang of KAERI

Denting

Sludge pile

in diameter

The SGT is made of nickel basedInconel alloy which is composed of 75 Ni 165Cr and 815Fe

-Degradation mechanism corrosion pitting denting inter granular attack

-Inspection Eddy current Testing(ECT)

Permeability Variation Clusters (PVC)

(Ferro-magnetic phase)

-005

000

005

010

015

m (emug)

1-1

-002

000

002

004

006

008

m (emug)

1-2

-1000 -500 0 500 1000

-015

-010

-005

H ( Am )

-1000 -500 0 500 1000

-006

-004

-002

H ( Am )

The hystresis loop in the fragment of PVC parts of Kori-1 retired SG tube

-004

-002

000

002

004

006

M (emug)

Inconel 600 tested at RT

under tensile stress

1 2 3

4 5 6

7 8 9-004

-002

000

002

004

006

M(emug)

Inconel 600 Heat treated at

602 oC under tensile stress

1 2 3

How can we detect magnetic phase

(PVC)selectively from the flaws in SGT

-3000 -2000 -1000 0 1000 2000 3000

-006

H (Oe)

7 8 9

10 11 12

-3000 -2000 -1000 0 1000 2000 3000

-006

-004

H(Oe)

4 5 6

7 8 9

The hysteresis loop of the tensile tested specimen at room temperature (a) and tensile tested at high temperature (b)

The magnetic phase can be created under the high temperature andpressure conditions which is correspond to the stress corrosion crackingin the SG tube in the NPP(Bruemmer SM Charlot LA amp Henager CH (1988) Corrosion 782)

Principle of ECT

If we can separate magnetic phase selectively from the

flaws using magnetic sensor the reliability of EC in SGT

inspection will be greatly enhanced

Structure of the permeability

sensor

Dimension and photograph of U-shape

sensing yoke

Design of Magnetic Sensor for PVC

sensor sensing yoke

Photograph of the completed sensor front side (above) and rear side (bottom)

R11R12

R10

R8

R6

R9

R13

R7

R14

C18

1 n

C17

C20

C21

D2

DIODE

SIN COS

-

+

U-2A

4

13

2

-

+

U-2B

75

6

8

-

+

U-3A

13

2

8

+5VC19

104

+5V

Schematic diagram of the sensor system

Electronic Circuit of Magnetic Sensor

R20

R

R21

R

-

+

U5AD797

3

26

74

U6

D1

S12

GND3

+VCC4VCC5

IN6

-VCC7

S28

C41

R13

R26

R18

R25

R2210 Ω

R16

R14

R17

10 k

R15

R27

R32

R28

R33

R29

R34

5 k

R30

C29

C37

104

C32473

C39473C40

104

C33

104

C21

104C23

104

C25

104

C26

104

C30

104

C31

104

C35

104

C36

104

C27

104

C28

104

C34

104

C38

104

D3

DIODE

L1

1

2

L2

1

2

L3

1

2

4

-

+

U-4A

4

13

2

-

+

U-4B

75

6

8

-

+

U-5A

4

13

2

-

+

U-5B

75

6

8

-

+

U-6A

4

13

2

-

+

U-6B

75

6

8

C22

104

-5V

+5V

+5V

+5V

+5V

+5V

+5V

U7

D1

S12

GND3

+VCC4

VCC5

IN6

-VCC7

S28

+5V

-5V

-5V

-5V

-5V

-5V

-5V

-5V

-5V

R19

R24

R

R23

R

C24

OUT(X)

OUT(Y)

R1

20 kR210 k

R3

20 kR410 k

C1

104

C8

104

REF43

OUT(X)

OUT(Y)

REF43

U2

+Vcc1

CH02

CH13

CH24

CH35

COMM6

SHDN7

Vref8

+Vcc9

GND10

GND11

DOUT12BUSY13DIN14CS15

DIN16

-

+

U-1A

13

2

8

-

+

U-1B

4

75

6

C410 uF

C5104

DOUT

C210uF

C6104

C3104

DCLK

C7104

DIN

C10

01uF

CS

BUSY

C14 10uF

J1

CON6

123456

D1

DIODE

R5

47K

C9

10uF

C1310uF

Y1

OSC

OUT3

GND2

VCC4

U3

RSTVPP1

GND10

VCC20

XTAL15

XTAL24

P10AIN012P11AIN113P1214P1315P1416P1517P1618P1719

P30RXD2

P31TXD3

P32INT06

P33INT17

P34T08

P35T19

P3711

U4

C1+1

C1-3

C2+4

C2-5

VCC16

GND15

V+2

V-6

R1OUT12

R2OUT9

T1IN11

T2IN10

R1IN13

R2IN8

T1OUT14

T2OUT7

C12 10uF

C16

01uF

C15 10uF

C11

01uF

-5V

+5V

+5V

+5V

+5V

+5V

+5V

+5V

RST

OSC

OSC

RST

DCLKCSDINBUSYDOUT

U1

IN2

GND

4

OUT6

TEMP3

TRIM5

-5V

+5V

Electronic circuit diagram of the magnetic sensor

Photograph of the completed measuring system data acquisition

software in PC and probe scanning system

Experimental Setup for Magnetic Sensor

Reference material Scanning System Software LabVIEW

Reference Material (1) Normal defects and PVCs

Longitudinal and transverse defects

Def W L D Remarks

1 02 500 0213 (20 ) Inner defects

2 02 500 0427 (40 )

3 02 500 0213 (20 )Outer defectsPVC(1018)4 02 500 0427 (40 )

5 02 500 0639 (60 )

6 02 500 0852 (80 )

7 02 500 0639 (60 ) Inner defects

8 02 500 0852 (80 )

- 1 and 2 are inner defects

- 345 and 6 are outer defects with PVC

- 7 and 8 are inner defects

PVC

PVC

Defect Defect

For longitudinal defects and PVC For circumferential defects and PVC

ECT is very difficult to detect circumferential defects

We can distinguish PVCs and defects and longitudinal and circumferential defects

Flux-gate Magnetometer

One core sensor Two core sensor

3-축 flux-gate Magnetometer의 계략도

Sensorpia Co

pro

cess

or(

AV

R)

Sensor 1

RS422

Interface

Mic

ro-p

roce

ssor(

AV

R)

Sensor 2

Sensor 3

Interface

조립된 마그네토미터의 사진

Sensorpia Co

Analog PCB

Digital PCB

Sensorpia Co선형도(linearity)

10

20

30

40

50

60

y-axis

Magnetometer Output (microT)

-60 -50 -40 -30 -20 -10 0 10 20 30 40 50 60

-60

-50

-40

-30

-20

-10

0

10

Y-axis y=099946 x+0015STD 106E-4

Magnetometer Output (

Applied Magnetic Field (microT)

마그네토미터의 noise 특성 Sensorpia Co

1

10

100

y-axis

Magnetometer noise (nT)

0 1 2 3 4 5 6

1E-4

1E-3

001

01

Magnetometer noise (nT)

Frequency (Hz)

Magnetometer for KoDSAT

-150 -100 -50 0 50 100 150

-15

-10

-5

0

5

10

15

Magnetic Moment (Am

2)

Current (mA)

After Thermal Cycle Test

Measured

Resistance 193 ohm

Photograph of Magnetic torquer

Photograph of KoDSAT

Photograph of

3-axis Fluxgate

Magnetometer

Photograph of Magnetic torquer

Application of magnetometer

Moon magnetic fieldmeasurement

Telescope with direction indication

Joule Effect (Magnetostriction)

ϕ2cosel

l=

∆

0=∆

+∆

+∆

b

b

a

a

l

l

Actuator using Terfenol-D

00

05

10

B (T)

800

1000

1200

1400

1600

Magnetostriction (ppm)

-100 -50 0 50 100

-10

-05

00

B (T)

H (kAm)

2 MPa

4 MPa

6 MPa

8 MPa

10 MPa

12 MPa

-100 -50 0 50 100

-200

0

200

400

600

Magnetostriction (ppm)

H (kAm)

2 MPa

4 MPa

6 MPa

8 MPa

10 MPa

12 MPa

600

700

800

900

1000

-4 -3 -2 -1 0 1 2 3 4

0

10

20

30

40

50

60

Displacement (m

icro meter)

I (A)

FIELD

9 kAm

12 kAm

16 kAm

20 kAm

24 kAm

38 kAm

-50 -40 -30 -20 -10 0 10 20 30 40 50

-100

0

100

200

300

400

500

L (PPM)

H (kAm)

9 kAm

12 kAm

16 kAm

20 kAm

24 kAm

38 kAm

Magnetostrictive displacement sensor

Hysteresis loops under

tensile stress σ

(a) Crystalline 68 NiFe

λs = +25 10-6

(b) crystalline pure Ni λs

= -35 10-6

Villari Effect ( Inverse of Joule Effect)

= -35 10-6

(c) amorphous Co-based

alloy

λs = -35 10-6

ϕσλ 2sin2

3sdotsdot= smeE

γ

Permeability depending on the stress

σλmicromicro

1

3

2

Y

J

so

s

r =

γ

Calculated magnetization curves under stress

Variation of magnetization curve by an applied

tensile force (Co-based amorphous alloy)

Alloy Requirement

Materials for magnetoelastic sensors

Why amorphous magnetic materials are important

Stress-strain curves of several materials

Coercivity and hardness of several materials

Principles of magnetoelastic sensors

Non-contact torque sensor

Principle of cross torductor torque

sensor and flux pattern of sensor

poles on the surface of a shaft

a) without and b)with torsional load

Equivalent magnetic circuit of

cross type torque sensor

Helices of principal tensile and compressive stress on the surface of

a shaft subjected to torsion [32] Correlated changes of permeability

are detected by four-branch yoke system with sensing coils 123

and 4 and a common excitation pole

Examples of torque sensors

Four-branch type torque sensor

heads Pole structures realized

by commercial multi-pole

ferrites 14 and 18 min in

diameter (diameter of sensor

h e a d 1 7 a n d 2 4 m m

respectively) respectively)

Principle of Ring Torductor torque transducer

(a b) Physical structure (c) evolution of the

shaft surface under the transducer poles A and BRing torductor for measuring

torque on ship propeller shafts

(shaft diameter ca 500 mm)

(Courtesy ASEA Brown

Boveri AG)

Principal designs of coaxial torque sensors

Schematic diagram of data processing

electronics of a torque sensor

Extensometer (a) Construction of strain sensing element using

amorphous ribbon wound core (b) configuration of lumped

windings

∆E effect of an amorphous FeNi-based

alloy (Fe40 Ni38 Mo4 B18) Hs saturation

field

Magnetically tunable delay line

Torque Sensors using Amorphous wire

Sixtus tonk효과(large Barkhausen효과)

Hysteresis loops of a Wiegand wire for different reset fields

Curie 온도 및Hopkinson효과

Relation between normalised

saturation polarisation and

normalised Curie temperature

Permeability of a Mn-Zn ferrite as

a function of temperature and field

strength

Conclusions

1) Magnetic sensor 는 자동차 공장자동화 항공우주 및 군사용으로많이 사용되고 있다

2) 새로운 소재개발은 자기센서의 성능개발에 직접적인 영향을 준다2) 새로운 소재개발은 자기센서의 성능개발에 직접적인 영향을 준다

3) 센서의 개발을 위해서는 다양한 전공지식이 요구된다

(물리학 재료공학 기계공학 전자공학)

4) 센서분야가 고부가가치를 창출하는 부품사업이다

5) 핵심부품을 생산하는 중소기업의 item으로도 적절하다

World market of sensors

West European market of sensorsWest European market of sensors

Sensor VariablesSecondary

Signal

Primary

Signal

Mechanical Thermal Electrical Magnetic Radiant Chemical

Mechanical

(Fluid) Mechanical and Acoustic Effects

eg Diaphragm

Gravity Balance

Echo Sounder

Friction Effects

(eg Friction

Calorimeter)

Coolings Effects

(eg Thermal Flow

Meters)

Piezoeletricity

Peizoresistivity

Resistive Capacitive

and Inductive Effects

Magnetomechanical Effects eg Piezomagnetic

Effect

Photoelastic Systems

(Stress-induced

Birefringence)

Interferometers

Sagnac Effect

Doppler Effect

Thermal

Thermal Expansion

(Bimetalic Strip Liquid-in-Glass and Gas Thermometers Resonant Frequency)

Radiometer Effect

(Light Mill)

Seebeck Effect

Thermoresistance

Pyroelectricity

Thermal (Johnsen)

Noise

Thermooptical Effects

(eg in Liquid Crystals)

Radiant Emission

Reaction Activation

eg Thermal Dissociation

Electrokinetic and Joule (Resistive) Heating Charge Collectors Biot-Savartrsquos Law Electrooptical Electrolysis

Electrical

Electrokinetic and Electromechanical Effects

eg Piezoelectricity

Electrometer

Amperersquos Law

Joule (Resistive) Heating

Peltier Effect

Charge Collectors

Langmuir Probe

Biot-Savartrsquos Law Electrooptical Effects

eg Kerr Effect

Pockels Effect

Electroluminescence

Electrolysis

Electromigration

Magnetic

Magnetomechanical Effects

eg Magnetostriction

Magnetometer

Thermomagnetic Effects

eg Righi-Leduc Effect

Galvanomagnetic Effect

eg Ettingshausen Effect

Thermomagnetic Effects eg Ettingshausen-Nernst Effect

Galvanomagnetic Effects

eg Hall Effects

Magnetoresistance

Magnetooptical Effects

Faraday Effect

Cotton-Mouton

Effect

Radiant

Radiation Pressure Bolometer

Thermopile

Photoelectric Effects

eg Photovoltaic Effect

Photoconductive Effect

Phtorefractive Effects

Optical Bistability

Photosynthesis

-dissociation

Chemical

Hygrometer

Electrodeposition Cell

Photoacoustic Effect

Calorimeter

Thermal Conductivity

Cell

Potentiometry Conductimetry

Amperometry

Flame Ionization

Volta Effect

Gas Sensitive Field Effect

Nuclear Magnetic

Resonance

(Emission and Absorp-tion)

Spectroscopy

Chemiluminescence

Quantities to be measured

Transfercharacteristics

Measured quantity

TempForce

Linearity

Important Sensor Variables

ForceTorquePHLight intensityCurrentVoltageMagnetic FieldElectric Field

LinearityResolution Noise Measuring rangeFrequency range (dynamic response)

ChargeVoltageCurrent

FrequencyPhase

Response Curves of the Sensors

Trends in Sensor Development

MEMS based sensorsBio-sensorsSmart and intelligent sensors Sensors for networkingSensors for home automation

Sensor in Automobiles

Definition of Magnetic Sensor

Sensors which are associated with the laws and effects of magnetic and electromagnetic fields

Why are Magnetic Sensors ImportantWhy are Magnetic Sensors Important

1) High reliability Military Flux-gate Search coil

Automobile ABS non-contact angle

Air and space Magnetic torquer Flux-gate

2) High Temperature LVDT Flux-gate

3) High radiation Eddy current probe and LVDT used in nuclear

power plant

Magnetic Effects for SensorsYear Effect Explanation Technical Use

1842 Joule effect Change in shape of a ferromagnetic body with magnetization (magnetostriction)

In combination with piezoelectric elements for magnetometers and potentiometers

1846 ΔE effect Chang in Youngrsquos modulus with magnetization Acoustic delay line components for magnetic field measurement

1847 Matteucci effect Torsion of a ferromagnetic rod in a longitudinal field changes magnetization

Magnetoelastic sensor

1856 Magnetoresistance

(AMR)

Change in resistance with magnetic field Magnetoresistive sensors

1858 Wiedemann effect A torsion is produced in a current carrying ferromagnetic rod when subjected to a longitudinal field

Torque and force measurement

1865 Villari effect Effect on magnetization by tensile or compressive strength

Magnetoelastic sensorsstrength

1879 Hall effect A current carrying crystal produces a transverse voltage when subjected to a magnetic field vertical to its surface

Magnetogalvanic sensors

1903 Skin effect Displacement of current from the interior of material to surface layer due to eddy currents

Distance sensors proximity sensors

1931 Sixtus Tonks effect Pulse magnetization by large Barkhausen jumps Wiegand and pulse-wire sensors

1962 Josephson effect Tunnel effect between two superconducting materials with an extremely thin separating layer quantum effect

SQUID magnetometers

1987 GMR effect Quantum mechanical magnetoresistance effect observed in thin-film structures composed of alternating ferromagnetic and non-magnetic conductive layers

Magnetic field sensor

Sprintonics

1994 GMI effect Large variations that the electrical impedance of some materials exhibits as a function of an external magnetic field

Magnetic field sensor

Principle of search coil type magnetometerPrinciple of search coil type magnetometer

int intint sdotminus=sdotA

ABt

sE d d

dd

Faradayrsquos Induction Law

Faraday 전자기유도법칙

Atd

HAnnU sdotsdotsdotsdot=Φsdotsdot= microωω max0

Voltage output from magnetometer

Sensitivity and Noise of Air Cored Induction Coil

HfDnHAnnU sdotsdotsdotsdotsdot=sdotsdotsdotsdot=Φsdotsdot= 02

2

0max02

microπ

microωω

2

022

00

microπ sdotsdot=

sdot=

Dn

Hf

US

V2π

sdotsdot=

sdotsdot

sdot= minus2

-970

m Hz nT

V10

m A

S V104πmicro

sdot

sdotsdot= minus

Hz nT

V10

2

922

0 DnUπ

Air-cored induction coil in a time-varying magnetic field

sdot

sdotsdot= minus

Hz nT

V10

2

922

0 DnUπ

Air-cored coil output voltage U0 at a magnetic field x frequency product

1 nT middot Hz versus diameter D with number of turns n as parameter

4

22 dDnWW

sdotsdotsdotsdot=

γπ Weight of coil

Coil resistance2

4

d

nDRDC

ρ=

Thermal voltage noisefTRU DCBN ∆= κ4

W

4W

DnfTU BN

sdotsdotsdotsdot∆=

πγρκ

fHnDdTk

DfHW

TkU

UNS

BBN

sdotsdotsdot

=sdotsdotsdot

== 21302

w00 )(28242

σmicroπ

γρmicroπ

Noise voltage

1028

ln286 9minussdot

+minus= αd

DDL

Equivalent circuit diagram of an air-cored induction coil

For single turn loop Dgtgtd

Long single layer solenoid

[H] 10 H][ 10 922

9222

minusminus sdotsdotsdot

=sdotsdotsdot

asympwd

nD

w

nDL

ππ

622

10 101 46

minussdot+sdot

asympwD

nDL

922

10 10 9 3

778 minussdot++sdot

asymphwD

nDL

Short single layer solenoid wgt16D

Multi-layer solenoid Dgtgtwh

( ) 1

370

ndc

DwC r

sdotminussdotsdotsdot

=ε

1

i

2tot minus+=k

C

k

CC

Capacitance C of a coil

Capacitance C of a single-layer coil normalized to

its diameter D versus length-to-diameter ratio wD

of the coil (capacitance C in pF and geometrical

dimensions w and D in cm)

12 minuskk

High permeability core induction coil

Magnetic field pattern around high permeability core

when it is inserted into a homogeneous field It is valid

for low frequencies and if the coil indicated at the middle

of the core is without current

Magnetization of a high permeability core

dt

dnu ci

i Φ

sdotminus= ) ( cosmaxc ci tωsdotΦ=Φ

ci0rc0 maxAHnnU sdotsdotsdotsdot=Φsdotsdot= micromicroωω

HNHHHH )1( minusminus=+= micro

HN

H sdotminus+

=)1(1

1

r

i micro

irdmi HNHHHH )1( minusminus=+= micro

HfAnU sdotsdotsdotsdotsdotsdot= 0cc0 2 micromicroπ

)1(1 r

rc minus+=

micromicro

microN

minus++

minusminus=

infin1)1ln(

11

1 2

22ell mmm

m

mN

10326) (1ln 152

10156) (1ln 262

ell

cyl

++++

=infin

infin

N

N

Induction coil on a cylindrical high permeability core

Demagnetization factorDemagnetization factorN of prolate ellipsoidsand cylindrical rods(descending curves) andcore permeability μc

(ascending curves) ofcylindrical rods versusthe length-to-diameterratio m of the rod withmaterial permeability μr

as parameter

Core permeability μc of cylindrical rods versus thematerial permeability μr with length-to-diameter ratiom of the rod as parameter after

Minimum noise equivalent magnetic field spectral density of an induction coil sensor with high permeability core versus sensor weight Ws (at length-to-diameter ratios m = 50 and 100 permeability μr = 10000 of the core material and f = 1 Hz)

Induction coil sensors with electronic amplifier

II

rKLC

1=ω

II

II

RR

RK

+=

rr

2 i 1

)(

ωω

ωω

ω

D

KF

+

minus

=

+=

II

II

II

2

C

L

R

R

C

L

KD

Frequency responses of the search coil

Frequency responses of thesensitivity SA and the output voltage UA

of an induction coil sensor with a voltageamplifier at a constant magnetic fieldamplitude

Resonance step-up of thesensitivity SA at differentvalues of the damping D

Sensor with transformer coupled negative feedback to the coil

)(i)()(F

0 ωωωω FR

UMUAU A

A sdot

minus=

)( i1

)(

F

0

ωω

ω

FR

MA

FAUU A

sdot+

sdot=

Induction coil connected to a voltage amplifier with

transformer coupled negative feedback to the coil

FR

21

1K0

i1

1

i1

i )(

ωωωωωω

ωω

+sdot

+sdot=

M

RUU A

IIF2 CRL

MAf

sdotsdotsdotsdot

=∆π

Frequency response of the output voltage UA of an induction coil sensor with negative feedback transformer coupled to the coil

Applications of search coil magnetometer

Developed search coil magnetometer using amorphous ribbon

Experimental setup for the effective permeability measurement

Relative permeability depending on the numbers of ribbon(a)

and the air gap between ribbons

Relative permeability depending on the number of ribbons for the different air gap between ribbons

Relative permeability depending on the total number of ribbons for the different air gap between ribbons

10 pT

100 pT

1 pT

Noise spectrum of the developed search coil magnetometer

BJne

E xH

1minus=

neRH

1minus=

22 nP micromicro minus

Hall 효과

Bt

IRU H

HL =

2

22

)( he

eh

Hpne

nPR

micromicromicromicro

+

minus=

Rectangular Hall plate (cc1cc2 current constant sc1sc2

sensor constant I bias current U voltage drop UH Hall

voltage

Physics carrier concentration and kind of carrier measurement

Engineering magnetic field measurement

Current Measurement

Arrangement for noninvasive

current measurement using an iron

core The current to be measured

produces a proportional magnetic

field which can be measured in the

air gap

Characteristic curve produced by

the current

Arrangement for indirect noninvasive

current measurement using the

compensation principle An iron core as

represented in Figure 3-29 is held field

free by injection a current into a

compensating coil wound on the core

which offsets the field generated by the

current being measured The Hall effect

sensor in the air gap serves as a null

indicator

Circuit diagram for AC-power

measurement using a Hall effect

sensor

DC Power Measurement

Circuit diagram for DC-

power measurement using a

Hall effect sensor

Noncontact Position Sensing

Galvanomagnetic components for sensing the position of permanent magnets

and magnetically conductive materials

Current Sensor Based on Hall Sensor

and Magnetic Core for Hybrid Vehicle

KH Yeon1 SD Kim1 and D Son2 1Auto industry co14F Hanshin IT tower Guro Gu Seoul Korea2Hannam UniversityOjung dong 133 Daejeon Rep of Korea

i

Hall sensor

B

I

SB

ring core

B

I10

g

N

Bl S

micro

)( gtgtrmicro

gab core

Current Sensor Based on Hall

Sensor and Magnetic Core

Hall

Effect

Device

CurrentVoltage

applying for

Hall effect device

operation

Output

signals

Magnetic field

Occurred by

current measurement

Signal

process

circuits

Developed Current Sensor

Magnetic core

Hall sensor

PCB

25

30

35

40

45

50

Output voltage V

Current sensor(Open loop type)

Temp 25C

400A model

+400 ~ -400A

SD 000128

Linearity 003

Linearity of the sensor

Characteristics of the Current Sensors

1000A 10 V power supply

-500 -400 -300 -200 -100 0 100 200 300 400 500

00

05

10

15

20

Output voltage V

current A

Temperature 25Linearity 003

Measuring range -400A ~ +400A

1000A Electronic Load

-3

0

3

6

9

12

15

18

dB

Current sensor

DV2 PCB 24pF

40Aturns

Frequency bandwidth

Gain bandwidth 3 MHz

Current 10 A

Temperature 25

Frequency bandwidth 100 kHz

Sensor output voltage vs frequency

at applied current of 40 Aturns

1 10 100

-18

-15

-12

-9

-6

Frequency kHz 측정온도 25

주파수특성 30kHz 이상(3dB 기준)

측정전류 40Aturns(4A 10턴)

측정주파수 100Hz ~ 100kHz

Temperature 25Current 40Aturns

Frequency range 100 Hz ~ 100 kHz

What is Magnetoresistance

Magnetoresistance effect(AMR)

θθθ 2cos2

12sin12cos(

22 minusminus+∆asymp∆ xxxmx hhhRR

32 minusasymp∆ ρρ New effect GMR CMR and GMI

10 ge∆ ρρ

Two bridge configuration for

rotational angle measurement

measurement angle more than 180o

자동차 Engine Management System

Inductive and Eddy Current

Sensors Excited by Permanent Magnets

tNtU dd)( φsdotminus=

construction of an inductive

sensor (courtesy VDO Adolf sensor (courtesy VDO Adolf

Schindling AG)

1) constant socket

2) terminal package

3) permanent magnet

4) cap

5) soft magnetic core

6) coil

7) plate

8) blade connector

γγ

Sensor with yoke Change in the magnetic flux with

varying air gap Continuous lines

minimum air gap dashed lines

maximum air gap

C-shaped sensor

Sensor with radially

magnetized

permanent magnet

Signal Conditioning

Output voltage U of a DC-excited sensor with permanent

magnets when a single iron object passes by

Schematic electrical diagram of an inductive sensor

Linear Variable Differential Transformer

AC-Excited Sensors for Linear Movement

Principle of construction of an LVDT

Electrical circuit of an LVDT

tIMtNU dd dd sdotminus=sdotminus= φ

tIMtIMUUU dd dd 1212 sdotminussdot=minus=

tIMMU dd)( 12 sdotminus=

)(12 xMMMM =minus=

tIxMU dd)( sdot= tI

UxM

dd)( =

Signal Conditioning

power supply

carrier gen

autoampcontrol

LVDTcarrieramp

demod-ulator

phase

shifter

power supply

carrier gen

passivedemod-ulator

LVDTDCamp

Block diagram of a carrier amplifier system

Block diagram of a DC amplifier system

Variable Inductive Sensors

Principle of construction

of the VLP sensor

Principle of a bridge

circuit

lANL r 20 sdotsdotsdot= micromicro

21 BA UUU minus=

21)i(ii( 211 minus+sdot= LLLUU BA ωωω

)21))()((( minus∆minus+∆+∆+sdot= LLLLLLUU BA

)212)(( minus∆+sdot= LLLUU )212)(( minus∆+sdot= LLLUU BA

LLUU BA 21 ∆sdotsdot=

llLL ∆sdot=∆ d d

llLLUU BA ∆sdotsdot= d d)2(1

Applications and Properties

Principle of a construction of a force transducer

(courtesy Hottinger Baldwin Messtechnik)

Vibrationacceleration sensor

Signal Conditioning

Schematic electrical diagram of a force transducer connected with an

amplifier (courtesy Hottinger Baldwin Messtechnik GmbH)

Variable Gap Sensors

)( FeFe2

0 LLllANL micromicromicro +sdotsdot=

FeFe2

0max lANL sdotsdotsdot= micromicro

Construction of a variable gap sensor

Characteristic of a variable gap sensor

Construction of a differential

cross-anchor sensor

Output voltage U versus core

position x plusmn a limits of the

linear rage

Applications of differential cross-anchor sensors

AC-excited Sensors for Rotary Movements

Principle of construction of a synchro

α cos10 sdotsdot= UKU y

)120-( cos10 degsdotsdot= αUKU z

)240-( cos10 degsdotsdot= αUKU x

)120-( sin3100 degsdotsdotsdot=minus= αKUUUU yxyx

)240-( sin3100 degsdotsdotsdot=minus= αKUUUU zyzy

α sin3100 sdotsdotsdot=minus= KUUUU xzxz

Application to the Torque Sensor

Principle of construction of a torque-type synchro

Torque versus angular

difference

)( sin~ rt αα minussdotKM

)( cos~ rt1r αα minussdotUU

Principle of construction of a control-type sensor

Output voltage versus

angular difference

Principle of construction of a differential sychro

Eddy Current Sensors

tBE dd curl minus=JH = curl

0 div =BH(H)B sdot= micro

E(E)J sdot= σ

A B curl= A B curl=

tdd- A E =

)dd( tAJ minus= σ

tdd curl curl AA σmicro minus=

AA) σωmicro iminus= curl )(curl(1

AA) σωmicro i=∆)((1

Eddy Current Tachometer

Construction of a speedometer (courtesy VDO Adolf Schinding AG) 1) spindle 2) bearing

3) holding spring 4) iron yoke 5) eddy current cup 6) shaft of the magnet 7) support of

the magnet 8) temperature compensation 9) permanent magnet 10) torsion spring

Proximity Sensors

Schematic diagram of a proximity sensor

Output current of a proximity switch versus distance

Inductive Flowmeters

)( Btimessdot= υqF

EqF sdot=BE times=υ

)(ds Btimes== υEU )(ds Btimes== υEU

)( Bd timessdot= υU

Bsdotsdotsdot= υdKU

Development of magnetic phase detection

sensor for steam generator tube

Dirac Son1 Kwan-Sang Ryu2 Duck-Gun Park3

1Hannam University Daejeon Rep of Korea2Korea Research Institute of Standards and Science Daejeon Rep of Korea3KoreaAtomic Energy Research Institute Daejeon Rep of Korea

Introduction

The layout of pressurized water reactor (PWR) components

Primary side Secondary side (non-radioactive side)(radioactive side)

The Structure of SG(Steam Generator)(degradation mechanism)

Secondary SidePrimary Side

SCC

A B

A-B

Steam outlet

Anti-vibration

SCC

Fretting

Wall thinning

IGA

U-bend

In commercial power plants SG- height up to 21 m - weight up to 800 tons - 2~4 sets of SG were installed - SG can contain from 3000 to

16000 tubes each about 20 mmin diameter

Primary coolant outlet Primary coolant inlet

Anti-vibrationbars

Tubesupportplate

Tubesheet

IGA

SCC

Pitting

SCC

Inside Tubesheet

Top of Tubesheet

by SSHwang of KAERI

Denting

Sludge pile

in diameter

The SGT is made of nickel basedInconel alloy which is composed of 75 Ni 165Cr and 815Fe

-Degradation mechanism corrosion pitting denting inter granular attack

-Inspection Eddy current Testing(ECT)

Permeability Variation Clusters (PVC)

(Ferro-magnetic phase)

-005

000

005

010

015

m (emug)

1-1

-002

000

002

004

006

008

m (emug)

1-2

-1000 -500 0 500 1000

-015

-010

-005

H ( Am )

-1000 -500 0 500 1000

-006

-004

-002

H ( Am )

The hystresis loop in the fragment of PVC parts of Kori-1 retired SG tube

-004

-002

000

002

004

006

M (emug)

Inconel 600 tested at RT

under tensile stress

1 2 3

4 5 6

7 8 9-004

-002

000

002

004

006

M(emug)

Inconel 600 Heat treated at

602 oC under tensile stress

1 2 3

How can we detect magnetic phase

(PVC)selectively from the flaws in SGT

-3000 -2000 -1000 0 1000 2000 3000

-006

H (Oe)

7 8 9

10 11 12

-3000 -2000 -1000 0 1000 2000 3000

-006

-004

H(Oe)

4 5 6

7 8 9

The hysteresis loop of the tensile tested specimen at room temperature (a) and tensile tested at high temperature (b)

The magnetic phase can be created under the high temperature andpressure conditions which is correspond to the stress corrosion crackingin the SG tube in the NPP(Bruemmer SM Charlot LA amp Henager CH (1988) Corrosion 782)

Principle of ECT

If we can separate magnetic phase selectively from the

flaws using magnetic sensor the reliability of EC in SGT

inspection will be greatly enhanced

Structure of the permeability

sensor

Dimension and photograph of U-shape

sensing yoke

Design of Magnetic Sensor for PVC

sensor sensing yoke

Photograph of the completed sensor front side (above) and rear side (bottom)

R11R12

R10

R8

R6

R9

R13

R7

R14

C18

1 n

C17

C20

C21

D2

DIODE

SIN COS

-

+

U-2A

4

13

2

-

+

U-2B

75

6

8

-

+

U-3A

13

2

8

+5VC19

104

+5V

Schematic diagram of the sensor system

Electronic Circuit of Magnetic Sensor

R20

R

R21

R

-

+

U5AD797

3

26

74

U6

D1

S12

GND3

+VCC4VCC5

IN6

-VCC7

S28

C41

R13

R26

R18

R25

R2210 Ω

R16

R14

R17

10 k

R15

R27

R32

R28

R33

R29

R34

5 k

R30

C29

C37

104

C32473

C39473C40

104

C33

104

C21

104C23

104

C25

104

C26

104

C30

104

C31

104

C35

104

C36

104

C27

104

C28

104

C34

104

C38

104

D3

DIODE

L1

1

2

L2

1

2

L3

1

2

4

-

+

U-4A

4

13

2

-

+

U-4B

75

6

8

-

+

U-5A

4

13

2

-

+

U-5B

75

6

8

-

+

U-6A

4

13

2

-

+

U-6B

75

6

8

C22

104

-5V

+5V

+5V

+5V

+5V

+5V

+5V

U7

D1

S12

GND3

+VCC4

VCC5

IN6

-VCC7

S28

+5V

-5V

-5V

-5V

-5V

-5V

-5V

-5V

-5V

R19

R24

R

R23

R

C24

OUT(X)

OUT(Y)

R1

20 kR210 k

R3

20 kR410 k

C1

104

C8

104

REF43

OUT(X)

OUT(Y)

REF43

U2

+Vcc1

CH02

CH13

CH24

CH35

COMM6

SHDN7

Vref8

+Vcc9

GND10

GND11

DOUT12BUSY13DIN14CS15

DIN16

-

+

U-1A

13

2

8

-

+

U-1B

4

75

6

C410 uF

C5104

DOUT

C210uF

C6104

C3104

DCLK

C7104

DIN

C10

01uF

CS

BUSY

C14 10uF

J1

CON6

123456

D1

DIODE

R5

47K

C9

10uF

C1310uF

Y1

OSC

OUT3

GND2

VCC4

U3

RSTVPP1

GND10

VCC20

XTAL15

XTAL24

P10AIN012P11AIN113P1214P1315P1416P1517P1618P1719

P30RXD2

P31TXD3

P32INT06

P33INT17

P34T08

P35T19

P3711

U4

C1+1

C1-3

C2+4

C2-5

VCC16

GND15

V+2

V-6

R1OUT12

R2OUT9

T1IN11

T2IN10

R1IN13

R2IN8

T1OUT14

T2OUT7

C12 10uF

C16

01uF

C15 10uF

C11

01uF

-5V

+5V

+5V

+5V

+5V

+5V

+5V

+5V

RST

OSC

OSC

RST

DCLKCSDINBUSYDOUT

U1

IN2

GND

4

OUT6

TEMP3

TRIM5

-5V

+5V

Electronic circuit diagram of the magnetic sensor

Photograph of the completed measuring system data acquisition

software in PC and probe scanning system

Experimental Setup for Magnetic Sensor

Reference material Scanning System Software LabVIEW

Reference Material (1) Normal defects and PVCs

Longitudinal and transverse defects

Def W L D Remarks

1 02 500 0213 (20 ) Inner defects

2 02 500 0427 (40 )

3 02 500 0213 (20 )Outer defectsPVC(1018)4 02 500 0427 (40 )

5 02 500 0639 (60 )

6 02 500 0852 (80 )

7 02 500 0639 (60 ) Inner defects

8 02 500 0852 (80 )

- 1 and 2 are inner defects

- 345 and 6 are outer defects with PVC

- 7 and 8 are inner defects

PVC

PVC

Defect Defect

For longitudinal defects and PVC For circumferential defects and PVC

ECT is very difficult to detect circumferential defects

We can distinguish PVCs and defects and longitudinal and circumferential defects

Flux-gate Magnetometer

One core sensor Two core sensor

3-축 flux-gate Magnetometer의 계략도

Sensorpia Co

pro

cess

or(

AV

R)

Sensor 1

RS422

Interface

Mic

ro-p

roce

ssor(

AV

R)

Sensor 2

Sensor 3

Interface

조립된 마그네토미터의 사진

Sensorpia Co

Analog PCB

Digital PCB

Sensorpia Co선형도(linearity)

10

20

30

40

50

60

y-axis

Magnetometer Output (microT)

-60 -50 -40 -30 -20 -10 0 10 20 30 40 50 60

-60

-50

-40

-30

-20

-10

0

10

Y-axis y=099946 x+0015STD 106E-4

Magnetometer Output (

Applied Magnetic Field (microT)

마그네토미터의 noise 특성 Sensorpia Co

1

10

100

y-axis

Magnetometer noise (nT)

0 1 2 3 4 5 6

1E-4

1E-3

001

01

Magnetometer noise (nT)

Frequency (Hz)

Magnetometer for KoDSAT

-150 -100 -50 0 50 100 150

-15

-10

-5

0

5

10

15

Magnetic Moment (Am

2)

Current (mA)

After Thermal Cycle Test

Measured

Resistance 193 ohm

Photograph of Magnetic torquer

Photograph of KoDSAT

Photograph of

3-axis Fluxgate

Magnetometer

Photograph of Magnetic torquer

Application of magnetometer

Moon magnetic fieldmeasurement

Telescope with direction indication

Joule Effect (Magnetostriction)

ϕ2cosel

l=

∆

0=∆

+∆

+∆

b

b

a

a

l

l

Actuator using Terfenol-D

00

05

10

B (T)

800

1000

1200

1400

1600

Magnetostriction (ppm)

-100 -50 0 50 100

-10

-05

00

B (T)

H (kAm)

2 MPa

4 MPa

6 MPa

8 MPa

10 MPa

12 MPa

-100 -50 0 50 100

-200

0

200

400

600

Magnetostriction (ppm)

H (kAm)

2 MPa

4 MPa

6 MPa

8 MPa

10 MPa

12 MPa

600

700

800

900

1000

-4 -3 -2 -1 0 1 2 3 4

0

10

20

30

40

50

60

Displacement (m

icro meter)

I (A)

FIELD

9 kAm

12 kAm

16 kAm

20 kAm

24 kAm

38 kAm

-50 -40 -30 -20 -10 0 10 20 30 40 50

-100

0

100

200

300

400

500

L (PPM)

H (kAm)

9 kAm

12 kAm

16 kAm

20 kAm

24 kAm

38 kAm

Magnetostrictive displacement sensor

Hysteresis loops under

tensile stress σ

(a) Crystalline 68 NiFe

λs = +25 10-6

(b) crystalline pure Ni λs

= -35 10-6

Villari Effect ( Inverse of Joule Effect)

= -35 10-6

(c) amorphous Co-based

alloy

λs = -35 10-6

ϕσλ 2sin2

3sdotsdot= smeE

γ

Permeability depending on the stress

σλmicromicro

1

3

2

Y

J

so

s

r =

γ

Calculated magnetization curves under stress

Variation of magnetization curve by an applied

tensile force (Co-based amorphous alloy)

Alloy Requirement

Materials for magnetoelastic sensors

Why amorphous magnetic materials are important

Stress-strain curves of several materials

Coercivity and hardness of several materials

Principles of magnetoelastic sensors

Non-contact torque sensor

Principle of cross torductor torque

sensor and flux pattern of sensor

poles on the surface of a shaft

a) without and b)with torsional load

Equivalent magnetic circuit of

cross type torque sensor

Helices of principal tensile and compressive stress on the surface of

a shaft subjected to torsion [32] Correlated changes of permeability

are detected by four-branch yoke system with sensing coils 123

and 4 and a common excitation pole

Examples of torque sensors

Four-branch type torque sensor

heads Pole structures realized

by commercial multi-pole

ferrites 14 and 18 min in

diameter (diameter of sensor

h e a d 1 7 a n d 2 4 m m

respectively) respectively)

Principle of Ring Torductor torque transducer

(a b) Physical structure (c) evolution of the

shaft surface under the transducer poles A and BRing torductor for measuring

torque on ship propeller shafts

(shaft diameter ca 500 mm)

(Courtesy ASEA Brown

Boveri AG)

Principal designs of coaxial torque sensors

Schematic diagram of data processing

electronics of a torque sensor

Extensometer (a) Construction of strain sensing element using

amorphous ribbon wound core (b) configuration of lumped

windings

∆E effect of an amorphous FeNi-based

alloy (Fe40 Ni38 Mo4 B18) Hs saturation

field

Magnetically tunable delay line

Torque Sensors using Amorphous wire

Sixtus tonk효과(large Barkhausen효과)

Hysteresis loops of a Wiegand wire for different reset fields

Curie 온도 및Hopkinson효과

Relation between normalised

saturation polarisation and

normalised Curie temperature

Permeability of a Mn-Zn ferrite as

a function of temperature and field

strength

Conclusions

1) Magnetic sensor 는 자동차 공장자동화 항공우주 및 군사용으로많이 사용되고 있다

2) 새로운 소재개발은 자기센서의 성능개발에 직접적인 영향을 준다2) 새로운 소재개발은 자기센서의 성능개발에 직접적인 영향을 준다

3) 센서의 개발을 위해서는 다양한 전공지식이 요구된다

(물리학 재료공학 기계공학 전자공학)

4) 센서분야가 고부가가치를 창출하는 부품사업이다

5) 핵심부품을 생산하는 중소기업의 item으로도 적절하다

Sensor VariablesSecondary

Signal

Primary

Signal

Mechanical Thermal Electrical Magnetic Radiant Chemical

Mechanical

(Fluid) Mechanical and Acoustic Effects

eg Diaphragm

Gravity Balance

Echo Sounder

Friction Effects

(eg Friction

Calorimeter)

Coolings Effects

(eg Thermal Flow

Meters)

Piezoeletricity

Peizoresistivity

Resistive Capacitive

and Inductive Effects

Magnetomechanical Effects eg Piezomagnetic

Effect

Photoelastic Systems

(Stress-induced

Birefringence)

Interferometers

Sagnac Effect

Doppler Effect

Thermal

Thermal Expansion

(Bimetalic Strip Liquid-in-Glass and Gas Thermometers Resonant Frequency)

Radiometer Effect

(Light Mill)

Seebeck Effect

Thermoresistance

Pyroelectricity

Thermal (Johnsen)

Noise

Thermooptical Effects

(eg in Liquid Crystals)

Radiant Emission

Reaction Activation

eg Thermal Dissociation

Electrokinetic and Joule (Resistive) Heating Charge Collectors Biot-Savartrsquos Law Electrooptical Electrolysis

Electrical

Electrokinetic and Electromechanical Effects

eg Piezoelectricity

Electrometer

Amperersquos Law

Joule (Resistive) Heating

Peltier Effect

Charge Collectors

Langmuir Probe

Biot-Savartrsquos Law Electrooptical Effects

eg Kerr Effect

Pockels Effect

Electroluminescence

Electrolysis

Electromigration

Magnetic

Magnetomechanical Effects

eg Magnetostriction

Magnetometer

Thermomagnetic Effects

eg Righi-Leduc Effect

Galvanomagnetic Effect

eg Ettingshausen Effect

Thermomagnetic Effects eg Ettingshausen-Nernst Effect

Galvanomagnetic Effects

eg Hall Effects

Magnetoresistance

Magnetooptical Effects

Faraday Effect

Cotton-Mouton

Effect

Radiant

Radiation Pressure Bolometer

Thermopile

Photoelectric Effects

eg Photovoltaic Effect

Photoconductive Effect

Phtorefractive Effects

Optical Bistability

Photosynthesis

-dissociation

Chemical

Hygrometer

Electrodeposition Cell

Photoacoustic Effect

Calorimeter

Thermal Conductivity

Cell

Potentiometry Conductimetry

Amperometry

Flame Ionization

Volta Effect

Gas Sensitive Field Effect

Nuclear Magnetic

Resonance

(Emission and Absorp-tion)

Spectroscopy

Chemiluminescence

Quantities to be measured

Transfercharacteristics

Measured quantity

TempForce

Linearity

Important Sensor Variables

ForceTorquePHLight intensityCurrentVoltageMagnetic FieldElectric Field

LinearityResolution Noise Measuring rangeFrequency range (dynamic response)

ChargeVoltageCurrent

FrequencyPhase

Response Curves of the Sensors

Trends in Sensor Development

MEMS based sensorsBio-sensorsSmart and intelligent sensors Sensors for networkingSensors for home automation

Sensor in Automobiles

Definition of Magnetic Sensor

Sensors which are associated with the laws and effects of magnetic and electromagnetic fields

Why are Magnetic Sensors ImportantWhy are Magnetic Sensors Important

1) High reliability Military Flux-gate Search coil

Automobile ABS non-contact angle

Air and space Magnetic torquer Flux-gate

2) High Temperature LVDT Flux-gate

3) High radiation Eddy current probe and LVDT used in nuclear

power plant

Magnetic Effects for SensorsYear Effect Explanation Technical Use

1842 Joule effect Change in shape of a ferromagnetic body with magnetization (magnetostriction)

In combination with piezoelectric elements for magnetometers and potentiometers

1846 ΔE effect Chang in Youngrsquos modulus with magnetization Acoustic delay line components for magnetic field measurement

1847 Matteucci effect Torsion of a ferromagnetic rod in a longitudinal field changes magnetization

Magnetoelastic sensor

1856 Magnetoresistance

(AMR)

Change in resistance with magnetic field Magnetoresistive sensors

1858 Wiedemann effect A torsion is produced in a current carrying ferromagnetic rod when subjected to a longitudinal field

Torque and force measurement

1865 Villari effect Effect on magnetization by tensile or compressive strength

Magnetoelastic sensorsstrength

1879 Hall effect A current carrying crystal produces a transverse voltage when subjected to a magnetic field vertical to its surface

Magnetogalvanic sensors

1903 Skin effect Displacement of current from the interior of material to surface layer due to eddy currents

Distance sensors proximity sensors

1931 Sixtus Tonks effect Pulse magnetization by large Barkhausen jumps Wiegand and pulse-wire sensors

1962 Josephson effect Tunnel effect between two superconducting materials with an extremely thin separating layer quantum effect

SQUID magnetometers

1987 GMR effect Quantum mechanical magnetoresistance effect observed in thin-film structures composed of alternating ferromagnetic and non-magnetic conductive layers

Magnetic field sensor

Sprintonics

1994 GMI effect Large variations that the electrical impedance of some materials exhibits as a function of an external magnetic field

Magnetic field sensor

Principle of search coil type magnetometerPrinciple of search coil type magnetometer

int intint sdotminus=sdotA

ABt

sE d d

dd

Faradayrsquos Induction Law

Faraday 전자기유도법칙

Atd

HAnnU sdotsdotsdotsdot=Φsdotsdot= microωω max0

Voltage output from magnetometer

Sensitivity and Noise of Air Cored Induction Coil

HfDnHAnnU sdotsdotsdotsdotsdot=sdotsdotsdotsdot=Φsdotsdot= 02

2

0max02

microπ

microωω

2

022

00

microπ sdotsdot=

sdot=

Dn

Hf

US

V2π

sdotsdot=

sdotsdot

sdot= minus2

-970

m Hz nT

V10

m A

S V104πmicro

sdot

sdotsdot= minus

Hz nT

V10

2

922

0 DnUπ

Air-cored induction coil in a time-varying magnetic field

sdot

sdotsdot= minus

Hz nT

V10

2

922

0 DnUπ

Air-cored coil output voltage U0 at a magnetic field x frequency product

1 nT middot Hz versus diameter D with number of turns n as parameter

4

22 dDnWW

sdotsdotsdotsdot=

γπ Weight of coil

Coil resistance2

4

d

nDRDC

ρ=

Thermal voltage noisefTRU DCBN ∆= κ4

W

4W

DnfTU BN

sdotsdotsdotsdot∆=

πγρκ

fHnDdTk

DfHW

TkU

UNS

BBN

sdotsdotsdot

=sdotsdotsdot

== 21302

w00 )(28242

σmicroπ

γρmicroπ

Noise voltage

1028

ln286 9minussdot

+minus= αd

DDL

Equivalent circuit diagram of an air-cored induction coil

For single turn loop Dgtgtd

Long single layer solenoid

[H] 10 H][ 10 922

9222

minusminus sdotsdotsdot

=sdotsdotsdot

asympwd

nD

w

nDL

ππ

622

10 101 46

minussdot+sdot

asympwD

nDL

922

10 10 9 3

778 minussdot++sdot

asymphwD

nDL

Short single layer solenoid wgt16D

Multi-layer solenoid Dgtgtwh

( ) 1

370

ndc

DwC r

sdotminussdotsdotsdot

=ε

1

i

2tot minus+=k

C

k

CC

Capacitance C of a coil

Capacitance C of a single-layer coil normalized to

its diameter D versus length-to-diameter ratio wD

of the coil (capacitance C in pF and geometrical

dimensions w and D in cm)

12 minuskk

High permeability core induction coil

Magnetic field pattern around high permeability core

when it is inserted into a homogeneous field It is valid

for low frequencies and if the coil indicated at the middle

of the core is without current

Magnetization of a high permeability core

dt

dnu ci

i Φ

sdotminus= ) ( cosmaxc ci tωsdotΦ=Φ

ci0rc0 maxAHnnU sdotsdotsdotsdot=Φsdotsdot= micromicroωω

HNHHHH )1( minusminus=+= micro

HN

H sdotminus+

=)1(1

1

r

i micro

irdmi HNHHHH )1( minusminus=+= micro

HfAnU sdotsdotsdotsdotsdotsdot= 0cc0 2 micromicroπ

)1(1 r

rc minus+=

micromicro

microN

minus++

minusminus=

infin1)1ln(

11

1 2

22ell mmm

m

mN

10326) (1ln 152

10156) (1ln 262

ell

cyl

++++

=infin

infin

N

N

Induction coil on a cylindrical high permeability core

Demagnetization factorDemagnetization factorN of prolate ellipsoidsand cylindrical rods(descending curves) andcore permeability μc

(ascending curves) ofcylindrical rods versusthe length-to-diameterratio m of the rod withmaterial permeability μr

as parameter

Core permeability μc of cylindrical rods versus thematerial permeability μr with length-to-diameter ratiom of the rod as parameter after

Minimum noise equivalent magnetic field spectral density of an induction coil sensor with high permeability core versus sensor weight Ws (at length-to-diameter ratios m = 50 and 100 permeability μr = 10000 of the core material and f = 1 Hz)

Induction coil sensors with electronic amplifier

II

rKLC

1=ω

II

II

RR

RK

+=

rr

2 i 1

)(

ωω

ωω

ω

D

KF

+

minus

=

+=

II

II

II

2

C

L

R

R

C

L

KD

Frequency responses of the search coil

Frequency responses of thesensitivity SA and the output voltage UA

of an induction coil sensor with a voltageamplifier at a constant magnetic fieldamplitude

Resonance step-up of thesensitivity SA at differentvalues of the damping D

Sensor with transformer coupled negative feedback to the coil

)(i)()(F

0 ωωωω FR

UMUAU A

A sdot

minus=

)( i1

)(

F

0

ωω

ω

FR

MA

FAUU A

sdot+

sdot=

Induction coil connected to a voltage amplifier with

transformer coupled negative feedback to the coil

FR

21

1K0

i1

1

i1

i )(

ωωωωωω

ωω

+sdot

+sdot=

M

RUU A

IIF2 CRL

MAf

sdotsdotsdotsdot

=∆π

Frequency response of the output voltage UA of an induction coil sensor with negative feedback transformer coupled to the coil

Applications of search coil magnetometer

Developed search coil magnetometer using amorphous ribbon

Experimental setup for the effective permeability measurement

Relative permeability depending on the numbers of ribbon(a)

and the air gap between ribbons

Relative permeability depending on the number of ribbons for the different air gap between ribbons

Relative permeability depending on the total number of ribbons for the different air gap between ribbons

10 pT

100 pT

1 pT

Noise spectrum of the developed search coil magnetometer

BJne

E xH

1minus=

neRH

1minus=

22 nP micromicro minus

Hall 효과

Bt

IRU H

HL =

2

22

)( he

eh

Hpne

nPR

micromicromicromicro

+

minus=

Rectangular Hall plate (cc1cc2 current constant sc1sc2

sensor constant I bias current U voltage drop UH Hall

voltage

Physics carrier concentration and kind of carrier measurement

Engineering magnetic field measurement

Current Measurement

Arrangement for noninvasive

current measurement using an iron

core The current to be measured

produces a proportional magnetic

field which can be measured in the

air gap

Characteristic curve produced by

the current

Arrangement for indirect noninvasive

current measurement using the

compensation principle An iron core as

represented in Figure 3-29 is held field

free by injection a current into a

compensating coil wound on the core

which offsets the field generated by the

current being measured The Hall effect

sensor in the air gap serves as a null

indicator

Circuit diagram for AC-power

measurement using a Hall effect

sensor

DC Power Measurement

Circuit diagram for DC-

power measurement using a

Hall effect sensor

Noncontact Position Sensing

Galvanomagnetic components for sensing the position of permanent magnets

and magnetically conductive materials

Current Sensor Based on Hall Sensor

and Magnetic Core for Hybrid Vehicle

KH Yeon1 SD Kim1 and D Son2 1Auto industry co14F Hanshin IT tower Guro Gu Seoul Korea2Hannam UniversityOjung dong 133 Daejeon Rep of Korea

i

Hall sensor

B

I

SB

ring core

B

I10

g

N

Bl S

micro

)( gtgtrmicro

gab core

Current Sensor Based on Hall

Sensor and Magnetic Core

Hall

Effect

Device

CurrentVoltage

applying for

Hall effect device

operation

Output

signals

Magnetic field

Occurred by

current measurement

Signal

process

circuits

Developed Current Sensor

Magnetic core

Hall sensor

PCB

25

30

35

40

45

50

Output voltage V

Current sensor(Open loop type)

Temp 25C

400A model

+400 ~ -400A

SD 000128

Linearity 003

Linearity of the sensor

Characteristics of the Current Sensors

1000A 10 V power supply

-500 -400 -300 -200 -100 0 100 200 300 400 500

00

05

10

15

20

Output voltage V

current A

Temperature 25Linearity 003

Measuring range -400A ~ +400A

1000A Electronic Load

-3

0

3

6

9

12

15

18

dB

Current sensor

DV2 PCB 24pF

40Aturns

Frequency bandwidth

Gain bandwidth 3 MHz

Current 10 A

Temperature 25

Frequency bandwidth 100 kHz

Sensor output voltage vs frequency

at applied current of 40 Aturns

1 10 100

-18

-15

-12

-9

-6

Frequency kHz 측정온도 25

주파수특성 30kHz 이상(3dB 기준)

측정전류 40Aturns(4A 10턴)

측정주파수 100Hz ~ 100kHz

Temperature 25Current 40Aturns

Frequency range 100 Hz ~ 100 kHz

What is Magnetoresistance

Magnetoresistance effect(AMR)

θθθ 2cos2

12sin12cos(

22 minusminus+∆asymp∆ xxxmx hhhRR

32 minusasymp∆ ρρ New effect GMR CMR and GMI

10 ge∆ ρρ

Two bridge configuration for

rotational angle measurement

measurement angle more than 180o

자동차 Engine Management System

Inductive and Eddy Current

Sensors Excited by Permanent Magnets

tNtU dd)( φsdotminus=

construction of an inductive

sensor (courtesy VDO Adolf sensor (courtesy VDO Adolf

Schindling AG)

1) constant socket

2) terminal package

3) permanent magnet

4) cap

5) soft magnetic core

6) coil

7) plate

8) blade connector

γγ

Sensor with yoke Change in the magnetic flux with

varying air gap Continuous lines

minimum air gap dashed lines

maximum air gap

C-shaped sensor

Sensor with radially

magnetized

permanent magnet

Signal Conditioning

Output voltage U of a DC-excited sensor with permanent

magnets when a single iron object passes by

Schematic electrical diagram of an inductive sensor

Linear Variable Differential Transformer

AC-Excited Sensors for Linear Movement

Principle of construction of an LVDT

Electrical circuit of an LVDT

tIMtNU dd dd sdotminus=sdotminus= φ

tIMtIMUUU dd dd 1212 sdotminussdot=minus=

tIMMU dd)( 12 sdotminus=

)(12 xMMMM =minus=

tIxMU dd)( sdot= tI

UxM

dd)( =

Signal Conditioning

power supply

carrier gen

autoampcontrol

LVDTcarrieramp

demod-ulator

phase

shifter

power supply

carrier gen

passivedemod-ulator

LVDTDCamp

Block diagram of a carrier amplifier system

Block diagram of a DC amplifier system

Variable Inductive Sensors

Principle of construction

of the VLP sensor

Principle of a bridge

circuit

lANL r 20 sdotsdotsdot= micromicro

21 BA UUU minus=

21)i(ii( 211 minus+sdot= LLLUU BA ωωω

)21))()((( minus∆minus+∆+∆+sdot= LLLLLLUU BA

)212)(( minus∆+sdot= LLLUU )212)(( minus∆+sdot= LLLUU BA

LLUU BA 21 ∆sdotsdot=

llLL ∆sdot=∆ d d

llLLUU BA ∆sdotsdot= d d)2(1

Applications and Properties

Principle of a construction of a force transducer

(courtesy Hottinger Baldwin Messtechnik)

Vibrationacceleration sensor

Signal Conditioning

Schematic electrical diagram of a force transducer connected with an

amplifier (courtesy Hottinger Baldwin Messtechnik GmbH)

Variable Gap Sensors

)( FeFe2

0 LLllANL micromicromicro +sdotsdot=

FeFe2

0max lANL sdotsdotsdot= micromicro

Construction of a variable gap sensor

Characteristic of a variable gap sensor

Construction of a differential

cross-anchor sensor

Output voltage U versus core

position x plusmn a limits of the

linear rage

Applications of differential cross-anchor sensors

AC-excited Sensors for Rotary Movements

Principle of construction of a synchro

α cos10 sdotsdot= UKU y

)120-( cos10 degsdotsdot= αUKU z

)240-( cos10 degsdotsdot= αUKU x

)120-( sin3100 degsdotsdotsdot=minus= αKUUUU yxyx

)240-( sin3100 degsdotsdotsdot=minus= αKUUUU zyzy

α sin3100 sdotsdotsdot=minus= KUUUU xzxz

Application to the Torque Sensor

Principle of construction of a torque-type synchro

Torque versus angular

difference

)( sin~ rt αα minussdotKM

)( cos~ rt1r αα minussdotUU

Principle of construction of a control-type sensor

Output voltage versus

angular difference

Principle of construction of a differential sychro

Eddy Current Sensors

tBE dd curl minus=JH = curl

0 div =BH(H)B sdot= micro

E(E)J sdot= σ

A B curl= A B curl=

tdd- A E =

)dd( tAJ minus= σ

tdd curl curl AA σmicro minus=

AA) σωmicro iminus= curl )(curl(1

AA) σωmicro i=∆)((1

Eddy Current Tachometer

Construction of a speedometer (courtesy VDO Adolf Schinding AG) 1) spindle 2) bearing

3) holding spring 4) iron yoke 5) eddy current cup 6) shaft of the magnet 7) support of

the magnet 8) temperature compensation 9) permanent magnet 10) torsion spring

Proximity Sensors

Schematic diagram of a proximity sensor

Output current of a proximity switch versus distance

Inductive Flowmeters

)( Btimessdot= υqF

EqF sdot=BE times=υ

)(ds Btimes== υEU )(ds Btimes== υEU

)( Bd timessdot= υU

Bsdotsdotsdot= υdKU

Development of magnetic phase detection

sensor for steam generator tube

Dirac Son1 Kwan-Sang Ryu2 Duck-Gun Park3

1Hannam University Daejeon Rep of Korea2Korea Research Institute of Standards and Science Daejeon Rep of Korea3KoreaAtomic Energy Research Institute Daejeon Rep of Korea

Introduction

The layout of pressurized water reactor (PWR) components

Primary side Secondary side (non-radioactive side)(radioactive side)

The Structure of SG(Steam Generator)(degradation mechanism)

Secondary SidePrimary Side

SCC

A B

A-B

Steam outlet

Anti-vibration

SCC

Fretting

Wall thinning

IGA

U-bend

In commercial power plants SG- height up to 21 m - weight up to 800 tons - 2~4 sets of SG were installed - SG can contain from 3000 to

16000 tubes each about 20 mmin diameter

Primary coolant outlet Primary coolant inlet

Anti-vibrationbars

Tubesupportplate

Tubesheet

IGA

SCC

Pitting

SCC

Inside Tubesheet

Top of Tubesheet

by SSHwang of KAERI

Denting

Sludge pile

in diameter

The SGT is made of nickel basedInconel alloy which is composed of 75 Ni 165Cr and 815Fe

-Degradation mechanism corrosion pitting denting inter granular attack

-Inspection Eddy current Testing(ECT)

Permeability Variation Clusters (PVC)

(Ferro-magnetic phase)

-005

000

005

010

015

m (emug)

1-1

-002

000

002

004

006

008

m (emug)

1-2

-1000 -500 0 500 1000

-015

-010

-005

H ( Am )

-1000 -500 0 500 1000

-006

-004

-002

H ( Am )

The hystresis loop in the fragment of PVC parts of Kori-1 retired SG tube

-004

-002

000

002

004

006

M (emug)

Inconel 600 tested at RT

under tensile stress

1 2 3

4 5 6

7 8 9-004

-002

000

002

004

006

M(emug)

Inconel 600 Heat treated at

602 oC under tensile stress

1 2 3

How can we detect magnetic phase

(PVC)selectively from the flaws in SGT

-3000 -2000 -1000 0 1000 2000 3000

-006

H (Oe)

7 8 9

10 11 12

-3000 -2000 -1000 0 1000 2000 3000

-006

-004

H(Oe)

4 5 6

7 8 9

The hysteresis loop of the tensile tested specimen at room temperature (a) and tensile tested at high temperature (b)

The magnetic phase can be created under the high temperature andpressure conditions which is correspond to the stress corrosion crackingin the SG tube in the NPP(Bruemmer SM Charlot LA amp Henager CH (1988) Corrosion 782)

Principle of ECT

If we can separate magnetic phase selectively from the

flaws using magnetic sensor the reliability of EC in SGT

inspection will be greatly enhanced

Structure of the permeability

sensor

Dimension and photograph of U-shape

sensing yoke

Design of Magnetic Sensor for PVC

sensor sensing yoke

Photograph of the completed sensor front side (above) and rear side (bottom)

R11R12

R10

R8

R6

R9

R13

R7

R14

C18

1 n

C17

C20

C21

D2

DIODE

SIN COS

-

+

U-2A

4

13

2

-

+

U-2B

75

6

8

-

+

U-3A

13

2

8

+5VC19

104

+5V

Schematic diagram of the sensor system

Electronic Circuit of Magnetic Sensor

R20

R

R21

R

-

+

U5AD797

3

26

74

U6

D1

S12

GND3

+VCC4VCC5

IN6

-VCC7

S28

C41

R13

R26

R18

R25

R2210 Ω

R16

R14

R17

10 k

R15

R27

R32

R28

R33

R29

R34

5 k

R30

C29

C37

104

C32473

C39473C40

104

C33

104

C21

104C23

104

C25

104

C26

104

C30

104

C31

104

C35

104

C36

104

C27

104

C28

104

C34

104

C38

104

D3

DIODE

L1

1

2

L2

1

2

L3

1

2

4

-

+

U-4A

4

13

2

-

+

U-4B

75

6

8

-

+

U-5A

4

13

2

-

+

U-5B

75

6

8

-

+

U-6A

4

13

2

-

+

U-6B

75

6

8

C22

104

-5V

+5V

+5V

+5V

+5V

+5V

+5V

U7

D1

S12

GND3

+VCC4

VCC5

IN6

-VCC7

S28

+5V

-5V

-5V

-5V

-5V

-5V

-5V

-5V

-5V

R19

R24

R

R23

R

C24

OUT(X)

OUT(Y)

R1

20 kR210 k

R3

20 kR410 k

C1

104

C8

104

REF43

OUT(X)

OUT(Y)

REF43

U2

+Vcc1

CH02

CH13

CH24

CH35

COMM6

SHDN7

Vref8

+Vcc9

GND10

GND11

DOUT12BUSY13DIN14CS15

DIN16

-

+

U-1A

13

2

8

-

+

U-1B

4

75

6

C410 uF

C5104

DOUT

C210uF

C6104

C3104

DCLK

C7104

DIN

C10

01uF

CS

BUSY

C14 10uF

J1

CON6

123456

D1

DIODE

R5

47K

C9

10uF

C1310uF

Y1

OSC

OUT3

GND2

VCC4

U3

RSTVPP1

GND10

VCC20

XTAL15

XTAL24

P10AIN012P11AIN113P1214P1315P1416P1517P1618P1719

P30RXD2

P31TXD3

P32INT06

P33INT17

P34T08

P35T19

P3711

U4

C1+1

C1-3

C2+4

C2-5

VCC16

GND15

V+2

V-6

R1OUT12

R2OUT9

T1IN11

T2IN10

R1IN13

R2IN8

T1OUT14

T2OUT7

C12 10uF

C16

01uF

C15 10uF

C11

01uF

-5V

+5V

+5V

+5V

+5V

+5V

+5V

+5V

RST

OSC

OSC

RST

DCLKCSDINBUSYDOUT

U1

IN2

GND

4

OUT6

TEMP3

TRIM5

-5V

+5V

Electronic circuit diagram of the magnetic sensor

Photograph of the completed measuring system data acquisition

software in PC and probe scanning system

Experimental Setup for Magnetic Sensor

Reference material Scanning System Software LabVIEW

Reference Material (1) Normal defects and PVCs

Longitudinal and transverse defects

Def W L D Remarks

1 02 500 0213 (20 ) Inner defects

2 02 500 0427 (40 )

3 02 500 0213 (20 )Outer defectsPVC(1018)4 02 500 0427 (40 )

5 02 500 0639 (60 )

6 02 500 0852 (80 )

7 02 500 0639 (60 ) Inner defects

8 02 500 0852 (80 )

- 1 and 2 are inner defects

- 345 and 6 are outer defects with PVC

- 7 and 8 are inner defects

PVC

PVC

Defect Defect

For longitudinal defects and PVC For circumferential defects and PVC

ECT is very difficult to detect circumferential defects

We can distinguish PVCs and defects and longitudinal and circumferential defects

Flux-gate Magnetometer

One core sensor Two core sensor

3-축 flux-gate Magnetometer의 계략도

Sensorpia Co

pro

cess

or(

AV

R)

Sensor 1

RS422

Interface

Mic

ro-p

roce

ssor(

AV

R)

Sensor 2

Sensor 3

Interface

조립된 마그네토미터의 사진

Sensorpia Co

Analog PCB

Digital PCB

Sensorpia Co선형도(linearity)

10

20

30

40

50

60

y-axis

Magnetometer Output (microT)

-60 -50 -40 -30 -20 -10 0 10 20 30 40 50 60

-60

-50

-40

-30

-20

-10

0

10

Y-axis y=099946 x+0015STD 106E-4

Magnetometer Output (

Applied Magnetic Field (microT)

마그네토미터의 noise 특성 Sensorpia Co

1

10

100

y-axis

Magnetometer noise (nT)

0 1 2 3 4 5 6

1E-4

1E-3

001

01

Magnetometer noise (nT)

Frequency (Hz)

Magnetometer for KoDSAT

-150 -100 -50 0 50 100 150

-15

-10

-5

0

5

10

15

Magnetic Moment (Am

2)

Current (mA)

After Thermal Cycle Test

Measured

Resistance 193 ohm

Photograph of Magnetic torquer

Photograph of KoDSAT

Photograph of

3-axis Fluxgate

Magnetometer

Photograph of Magnetic torquer

Application of magnetometer

Moon magnetic fieldmeasurement

Telescope with direction indication

Joule Effect (Magnetostriction)

ϕ2cosel

l=

∆

0=∆

+∆

+∆

b

b

a

a

l

l

Actuator using Terfenol-D

00

05

10

B (T)

800

1000

1200

1400

1600

Magnetostriction (ppm)

-100 -50 0 50 100

-10

-05

00

B (T)

H (kAm)

2 MPa

4 MPa

6 MPa

8 MPa

10 MPa

12 MPa

-100 -50 0 50 100

-200

0

200

400

600

Magnetostriction (ppm)

H (kAm)

2 MPa

4 MPa

6 MPa

8 MPa

10 MPa

12 MPa

600

700

800

900

1000

-4 -3 -2 -1 0 1 2 3 4

0

10

20

30

40

50

60

Displacement (m

icro meter)

I (A)

FIELD

9 kAm

12 kAm

16 kAm

20 kAm

24 kAm

38 kAm

-50 -40 -30 -20 -10 0 10 20 30 40 50

-100

0

100

200

300

400

500

L (PPM)

H (kAm)

9 kAm

12 kAm

16 kAm

20 kAm

24 kAm

38 kAm

Magnetostrictive displacement sensor

Hysteresis loops under

tensile stress σ

(a) Crystalline 68 NiFe

λs = +25 10-6

(b) crystalline pure Ni λs

= -35 10-6

Villari Effect ( Inverse of Joule Effect)

= -35 10-6

(c) amorphous Co-based

alloy

λs = -35 10-6

ϕσλ 2sin2

3sdotsdot= smeE

γ

Permeability depending on the stress

σλmicromicro

1

3

2

Y

J

so

s

r =

γ

Calculated magnetization curves under stress

Variation of magnetization curve by an applied

tensile force (Co-based amorphous alloy)

Alloy Requirement

Materials for magnetoelastic sensors

Why amorphous magnetic materials are important

Stress-strain curves of several materials

Coercivity and hardness of several materials

Principles of magnetoelastic sensors

Non-contact torque sensor

Principle of cross torductor torque

sensor and flux pattern of sensor

poles on the surface of a shaft

a) without and b)with torsional load

Equivalent magnetic circuit of

cross type torque sensor

Helices of principal tensile and compressive stress on the surface of

a shaft subjected to torsion [32] Correlated changes of permeability

are detected by four-branch yoke system with sensing coils 123

and 4 and a common excitation pole

Examples of torque sensors

Four-branch type torque sensor

heads Pole structures realized

by commercial multi-pole

ferrites 14 and 18 min in

diameter (diameter of sensor

h e a d 1 7 a n d 2 4 m m

respectively) respectively)

Principle of Ring Torductor torque transducer

(a b) Physical structure (c) evolution of the

shaft surface under the transducer poles A and BRing torductor for measuring

torque on ship propeller shafts

(shaft diameter ca 500 mm)

(Courtesy ASEA Brown

Boveri AG)

Principal designs of coaxial torque sensors

Schematic diagram of data processing

electronics of a torque sensor

Extensometer (a) Construction of strain sensing element using

amorphous ribbon wound core (b) configuration of lumped

windings

∆E effect of an amorphous FeNi-based

alloy (Fe40 Ni38 Mo4 B18) Hs saturation

field

Magnetically tunable delay line

Torque Sensors using Amorphous wire

Sixtus tonk효과(large Barkhausen효과)

Hysteresis loops of a Wiegand wire for different reset fields

Curie 온도 및Hopkinson효과

Relation between normalised

saturation polarisation and

normalised Curie temperature

Permeability of a Mn-Zn ferrite as

a function of temperature and field

strength

Conclusions

1) Magnetic sensor 는 자동차 공장자동화 항공우주 및 군사용으로많이 사용되고 있다

2) 새로운 소재개발은 자기센서의 성능개발에 직접적인 영향을 준다2) 새로운 소재개발은 자기센서의 성능개발에 직접적인 영향을 준다

3) 센서의 개발을 위해서는 다양한 전공지식이 요구된다

(물리학 재료공학 기계공학 전자공학)

4) 센서분야가 고부가가치를 창출하는 부품사업이다

5) 핵심부품을 생산하는 중소기업의 item으로도 적절하다

Quantities to be measured

Transfercharacteristics

Measured quantity

TempForce

Linearity

Important Sensor Variables

ForceTorquePHLight intensityCurrentVoltageMagnetic FieldElectric Field

LinearityResolution Noise Measuring rangeFrequency range (dynamic response)

ChargeVoltageCurrent

FrequencyPhase

Response Curves of the Sensors

Trends in Sensor Development

MEMS based sensorsBio-sensorsSmart and intelligent sensors Sensors for networkingSensors for home automation

Sensor in Automobiles

Definition of Magnetic Sensor

Sensors which are associated with the laws and effects of magnetic and electromagnetic fields

Why are Magnetic Sensors ImportantWhy are Magnetic Sensors Important

1) High reliability Military Flux-gate Search coil

Automobile ABS non-contact angle

Air and space Magnetic torquer Flux-gate

2) High Temperature LVDT Flux-gate

3) High radiation Eddy current probe and LVDT used in nuclear

power plant

Magnetic Effects for SensorsYear Effect Explanation Technical Use

1842 Joule effect Change in shape of a ferromagnetic body with magnetization (magnetostriction)

In combination with piezoelectric elements for magnetometers and potentiometers

1846 ΔE effect Chang in Youngrsquos modulus with magnetization Acoustic delay line components for magnetic field measurement

1847 Matteucci effect Torsion of a ferromagnetic rod in a longitudinal field changes magnetization

Magnetoelastic sensor

1856 Magnetoresistance

(AMR)

Change in resistance with magnetic field Magnetoresistive sensors

1858 Wiedemann effect A torsion is produced in a current carrying ferromagnetic rod when subjected to a longitudinal field

Torque and force measurement

1865 Villari effect Effect on magnetization by tensile or compressive strength

Magnetoelastic sensorsstrength

1879 Hall effect A current carrying crystal produces a transverse voltage when subjected to a magnetic field vertical to its surface

Magnetogalvanic sensors

1903 Skin effect Displacement of current from the interior of material to surface layer due to eddy currents

Distance sensors proximity sensors

1931 Sixtus Tonks effect Pulse magnetization by large Barkhausen jumps Wiegand and pulse-wire sensors

1962 Josephson effect Tunnel effect between two superconducting materials with an extremely thin separating layer quantum effect

SQUID magnetometers

1987 GMR effect Quantum mechanical magnetoresistance effect observed in thin-film structures composed of alternating ferromagnetic and non-magnetic conductive layers

Magnetic field sensor

Sprintonics

1994 GMI effect Large variations that the electrical impedance of some materials exhibits as a function of an external magnetic field

Magnetic field sensor

Principle of search coil type magnetometerPrinciple of search coil type magnetometer

int intint sdotminus=sdotA

ABt

sE d d

dd

Faradayrsquos Induction Law

Faraday 전자기유도법칙

Atd

HAnnU sdotsdotsdotsdot=Φsdotsdot= microωω max0

Voltage output from magnetometer

Sensitivity and Noise of Air Cored Induction Coil

HfDnHAnnU sdotsdotsdotsdotsdot=sdotsdotsdotsdot=Φsdotsdot= 02

2

0max02

microπ

microωω

2

022

00

microπ sdotsdot=

sdot=

Dn

Hf

US

V2π

sdotsdot=

sdotsdot

sdot= minus2

-970

m Hz nT

V10

m A

S V104πmicro

sdot

sdotsdot= minus

Hz nT

V10

2

922

0 DnUπ

Air-cored induction coil in a time-varying magnetic field

sdot

sdotsdot= minus

Hz nT

V10

2

922

0 DnUπ

Air-cored coil output voltage U0 at a magnetic field x frequency product

1 nT middot Hz versus diameter D with number of turns n as parameter

4

22 dDnWW

sdotsdotsdotsdot=

γπ Weight of coil

Coil resistance2

4

d

nDRDC

ρ=

Thermal voltage noisefTRU DCBN ∆= κ4

W

4W

DnfTU BN

sdotsdotsdotsdot∆=

πγρκ

fHnDdTk

DfHW

TkU

UNS

BBN

sdotsdotsdot

=sdotsdotsdot

== 21302

w00 )(28242

σmicroπ

γρmicroπ

Noise voltage

1028

ln286 9minussdot

+minus= αd

DDL

Equivalent circuit diagram of an air-cored induction coil

For single turn loop Dgtgtd

Long single layer solenoid

[H] 10 H][ 10 922

9222

minusminus sdotsdotsdot

=sdotsdotsdot

asympwd

nD

w

nDL

ππ

622

10 101 46

minussdot+sdot

asympwD

nDL

922

10 10 9 3

778 minussdot++sdot

asymphwD

nDL

Short single layer solenoid wgt16D

Multi-layer solenoid Dgtgtwh

( ) 1

370

ndc

DwC r

sdotminussdotsdotsdot

=ε

1

i

2tot minus+=k

C

k

CC

Capacitance C of a coil

Capacitance C of a single-layer coil normalized to

its diameter D versus length-to-diameter ratio wD

of the coil (capacitance C in pF and geometrical

dimensions w and D in cm)

12 minuskk

High permeability core induction coil

Magnetic field pattern around high permeability core

when it is inserted into a homogeneous field It is valid

for low frequencies and if the coil indicated at the middle

of the core is without current

Magnetization of a high permeability core

dt

dnu ci

i Φ

sdotminus= ) ( cosmaxc ci tωsdotΦ=Φ

ci0rc0 maxAHnnU sdotsdotsdotsdot=Φsdotsdot= micromicroωω

HNHHHH )1( minusminus=+= micro

HN

H sdotminus+

=)1(1

1

r

i micro

irdmi HNHHHH )1( minusminus=+= micro

HfAnU sdotsdotsdotsdotsdotsdot= 0cc0 2 micromicroπ

)1(1 r

rc minus+=

micromicro

microN

minus++

minusminus=

infin1)1ln(

11

1 2

22ell mmm

m

mN

10326) (1ln 152

10156) (1ln 262

ell

cyl

++++

=infin

infin

N

N

Induction coil on a cylindrical high permeability core

Demagnetization factorDemagnetization factorN of prolate ellipsoidsand cylindrical rods(descending curves) andcore permeability μc

(ascending curves) ofcylindrical rods versusthe length-to-diameterratio m of the rod withmaterial permeability μr

as parameter

Core permeability μc of cylindrical rods versus thematerial permeability μr with length-to-diameter ratiom of the rod as parameter after

Minimum noise equivalent magnetic field spectral density of an induction coil sensor with high permeability core versus sensor weight Ws (at length-to-diameter ratios m = 50 and 100 permeability μr = 10000 of the core material and f = 1 Hz)

Induction coil sensors with electronic amplifier

II

rKLC

1=ω

II

II

RR

RK

+=

rr

2 i 1

)(

ωω

ωω

ω

D

KF

+

minus

=

+=

II

II

II

2

C

L

R

R

C

L

KD

Frequency responses of the search coil

Frequency responses of thesensitivity SA and the output voltage UA

of an induction coil sensor with a voltageamplifier at a constant magnetic fieldamplitude

Resonance step-up of thesensitivity SA at differentvalues of the damping D

Sensor with transformer coupled negative feedback to the coil

)(i)()(F

0 ωωωω FR

UMUAU A

A sdot

minus=

)( i1

)(

F

0

ωω

ω

FR

MA

FAUU A

sdot+

sdot=

Induction coil connected to a voltage amplifier with

transformer coupled negative feedback to the coil

FR

21

1K0

i1

1

i1

i )(

ωωωωωω

ωω

+sdot

+sdot=

M

RUU A

IIF2 CRL

MAf

sdotsdotsdotsdot

=∆π

Frequency response of the output voltage UA of an induction coil sensor with negative feedback transformer coupled to the coil

Applications of search coil magnetometer

Developed search coil magnetometer using amorphous ribbon

Experimental setup for the effective permeability measurement

Relative permeability depending on the numbers of ribbon(a)

and the air gap between ribbons

Relative permeability depending on the number of ribbons for the different air gap between ribbons

Relative permeability depending on the total number of ribbons for the different air gap between ribbons

10 pT

100 pT

1 pT

Noise spectrum of the developed search coil magnetometer

BJne

E xH

1minus=

neRH

1minus=

22 nP micromicro minus

Hall 효과

Bt

IRU H

HL =

2

22

)( he

eh

Hpne

nPR

micromicromicromicro

+

minus=

Rectangular Hall plate (cc1cc2 current constant sc1sc2

sensor constant I bias current U voltage drop UH Hall

voltage

Physics carrier concentration and kind of carrier measurement

Engineering magnetic field measurement

Current Measurement

Arrangement for noninvasive

current measurement using an iron

core The current to be measured

produces a proportional magnetic

field which can be measured in the

air gap

Characteristic curve produced by

the current

Arrangement for indirect noninvasive

current measurement using the

compensation principle An iron core as

represented in Figure 3-29 is held field

free by injection a current into a

compensating coil wound on the core

which offsets the field generated by the

current being measured The Hall effect

sensor in the air gap serves as a null

indicator

Circuit diagram for AC-power

measurement using a Hall effect

sensor

DC Power Measurement

Circuit diagram for DC-

power measurement using a

Hall effect sensor

Noncontact Position Sensing

Galvanomagnetic components for sensing the position of permanent magnets

and magnetically conductive materials

Current Sensor Based on Hall Sensor

and Magnetic Core for Hybrid Vehicle

KH Yeon1 SD Kim1 and D Son2 1Auto industry co14F Hanshin IT tower Guro Gu Seoul Korea2Hannam UniversityOjung dong 133 Daejeon Rep of Korea

i

Hall sensor

B

I

SB

ring core

B

I10

g

N

Bl S

micro

)( gtgtrmicro

gab core

Current Sensor Based on Hall

Sensor and Magnetic Core

Hall

Effect

Device

CurrentVoltage

applying for

Hall effect device

operation

Output

signals

Magnetic field

Occurred by

current measurement

Signal

process

circuits

Developed Current Sensor

Magnetic core

Hall sensor

PCB

25

30

35

40

45

50

Output voltage V

Current sensor(Open loop type)

Temp 25C

400A model

+400 ~ -400A

SD 000128

Linearity 003

Linearity of the sensor

Characteristics of the Current Sensors

1000A 10 V power supply

-500 -400 -300 -200 -100 0 100 200 300 400 500

00

05

10

15

20

Output voltage V

current A

Temperature 25Linearity 003

Measuring range -400A ~ +400A

1000A Electronic Load

-3

0

3

6

9

12

15

18

dB

Current sensor

DV2 PCB 24pF

40Aturns

Frequency bandwidth

Gain bandwidth 3 MHz

Current 10 A

Temperature 25

Frequency bandwidth 100 kHz

Sensor output voltage vs frequency

at applied current of 40 Aturns

1 10 100

-18

-15

-12

-9

-6

Frequency kHz 측정온도 25

주파수특성 30kHz 이상(3dB 기준)

측정전류 40Aturns(4A 10턴)

측정주파수 100Hz ~ 100kHz

Temperature 25Current 40Aturns

Frequency range 100 Hz ~ 100 kHz

What is Magnetoresistance

Magnetoresistance effect(AMR)

θθθ 2cos2

12sin12cos(

22 minusminus+∆asymp∆ xxxmx hhhRR

32 minusasymp∆ ρρ New effect GMR CMR and GMI

10 ge∆ ρρ

Two bridge configuration for

rotational angle measurement

measurement angle more than 180o

자동차 Engine Management System

Inductive and Eddy Current

Sensors Excited by Permanent Magnets

tNtU dd)( φsdotminus=

construction of an inductive

sensor (courtesy VDO Adolf sensor (courtesy VDO Adolf

Schindling AG)

1) constant socket

2) terminal package

3) permanent magnet

4) cap

5) soft magnetic core

6) coil

7) plate

8) blade connector

γγ

Sensor with yoke Change in the magnetic flux with

varying air gap Continuous lines

minimum air gap dashed lines

maximum air gap

C-shaped sensor

Sensor with radially

magnetized

permanent magnet

Signal Conditioning

Output voltage U of a DC-excited sensor with permanent

magnets when a single iron object passes by

Schematic electrical diagram of an inductive sensor

Linear Variable Differential Transformer

AC-Excited Sensors for Linear Movement

Principle of construction of an LVDT

Electrical circuit of an LVDT

tIMtNU dd dd sdotminus=sdotminus= φ

tIMtIMUUU dd dd 1212 sdotminussdot=minus=

tIMMU dd)( 12 sdotminus=

)(12 xMMMM =minus=

tIxMU dd)( sdot= tI

UxM

dd)( =

Signal Conditioning

power supply

carrier gen

autoampcontrol

LVDTcarrieramp

demod-ulator

phase

shifter

power supply

carrier gen

passivedemod-ulator

LVDTDCamp

Block diagram of a carrier amplifier system

Block diagram of a DC amplifier system

Variable Inductive Sensors

Principle of construction

of the VLP sensor

Principle of a bridge

circuit

lANL r 20 sdotsdotsdot= micromicro

21 BA UUU minus=

21)i(ii( 211 minus+sdot= LLLUU BA ωωω

)21))()((( minus∆minus+∆+∆+sdot= LLLLLLUU BA

)212)(( minus∆+sdot= LLLUU )212)(( minus∆+sdot= LLLUU BA

LLUU BA 21 ∆sdotsdot=

llLL ∆sdot=∆ d d

llLLUU BA ∆sdotsdot= d d)2(1

Applications and Properties

Principle of a construction of a force transducer

(courtesy Hottinger Baldwin Messtechnik)

Vibrationacceleration sensor

Signal Conditioning

Schematic electrical diagram of a force transducer connected with an

amplifier (courtesy Hottinger Baldwin Messtechnik GmbH)

Variable Gap Sensors

)( FeFe2

0 LLllANL micromicromicro +sdotsdot=

FeFe2

0max lANL sdotsdotsdot= micromicro

Construction of a variable gap sensor

Characteristic of a variable gap sensor

Construction of a differential

cross-anchor sensor

Output voltage U versus core

position x plusmn a limits of the

linear rage

Applications of differential cross-anchor sensors

AC-excited Sensors for Rotary Movements

Principle of construction of a synchro

α cos10 sdotsdot= UKU y

)120-( cos10 degsdotsdot= αUKU z

)240-( cos10 degsdotsdot= αUKU x

)120-( sin3100 degsdotsdotsdot=minus= αKUUUU yxyx

)240-( sin3100 degsdotsdotsdot=minus= αKUUUU zyzy

α sin3100 sdotsdotsdot=minus= KUUUU xzxz

Application to the Torque Sensor

Principle of construction of a torque-type synchro

Torque versus angular

difference

)( sin~ rt αα minussdotKM

)( cos~ rt1r αα minussdotUU

Principle of construction of a control-type sensor

Output voltage versus

angular difference

Principle of construction of a differential sychro

Eddy Current Sensors

tBE dd curl minus=JH = curl

0 div =BH(H)B sdot= micro

E(E)J sdot= σ

A B curl= A B curl=

tdd- A E =

)dd( tAJ minus= σ

tdd curl curl AA σmicro minus=

AA) σωmicro iminus= curl )(curl(1

AA) σωmicro i=∆)((1

Eddy Current Tachometer

Construction of a speedometer (courtesy VDO Adolf Schinding AG) 1) spindle 2) bearing

3) holding spring 4) iron yoke 5) eddy current cup 6) shaft of the magnet 7) support of

the magnet 8) temperature compensation 9) permanent magnet 10) torsion spring

Proximity Sensors

Schematic diagram of a proximity sensor

Output current of a proximity switch versus distance

Inductive Flowmeters

)( Btimessdot= υqF

EqF sdot=BE times=υ

)(ds Btimes== υEU )(ds Btimes== υEU

)( Bd timessdot= υU

Bsdotsdotsdot= υdKU

Development of magnetic phase detection

sensor for steam generator tube

Dirac Son1 Kwan-Sang Ryu2 Duck-Gun Park3

1Hannam University Daejeon Rep of Korea2Korea Research Institute of Standards and Science Daejeon Rep of Korea3KoreaAtomic Energy Research Institute Daejeon Rep of Korea

Introduction

The layout of pressurized water reactor (PWR) components

Primary side Secondary side (non-radioactive side)(radioactive side)

The Structure of SG(Steam Generator)(degradation mechanism)

Secondary SidePrimary Side

SCC

A B

A-B

Steam outlet

Anti-vibration

SCC

Fretting

Wall thinning

IGA

U-bend

In commercial power plants SG- height up to 21 m - weight up to 800 tons - 2~4 sets of SG were installed - SG can contain from 3000 to

16000 tubes each about 20 mmin diameter

Primary coolant outlet Primary coolant inlet

Anti-vibrationbars

Tubesupportplate

Tubesheet

IGA

SCC

Pitting

SCC

Inside Tubesheet

Top of Tubesheet

by SSHwang of KAERI

Denting

Sludge pile

in diameter

The SGT is made of nickel basedInconel alloy which is composed of 75 Ni 165Cr and 815Fe

-Degradation mechanism corrosion pitting denting inter granular attack

-Inspection Eddy current Testing(ECT)

Permeability Variation Clusters (PVC)

(Ferro-magnetic phase)

-005

000

005

010

015

m (emug)

1-1

-002

000

002

004

006

008

m (emug)

1-2

-1000 -500 0 500 1000

-015

-010

-005

H ( Am )

-1000 -500 0 500 1000

-006

-004

-002

H ( Am )

The hystresis loop in the fragment of PVC parts of Kori-1 retired SG tube

-004

-002

000

002

004

006

M (emug)

Inconel 600 tested at RT

under tensile stress

1 2 3

4 5 6

7 8 9-004

-002

000

002

004

006

M(emug)

Inconel 600 Heat treated at

602 oC under tensile stress

1 2 3

How can we detect magnetic phase

(PVC)selectively from the flaws in SGT

-3000 -2000 -1000 0 1000 2000 3000

-006

H (Oe)

7 8 9

10 11 12

-3000 -2000 -1000 0 1000 2000 3000

-006

-004

H(Oe)

4 5 6

7 8 9

The hysteresis loop of the tensile tested specimen at room temperature (a) and tensile tested at high temperature (b)

The magnetic phase can be created under the high temperature andpressure conditions which is correspond to the stress corrosion crackingin the SG tube in the NPP(Bruemmer SM Charlot LA amp Henager CH (1988) Corrosion 782)

Principle of ECT

If we can separate magnetic phase selectively from the

flaws using magnetic sensor the reliability of EC in SGT

inspection will be greatly enhanced

Structure of the permeability

sensor

Dimension and photograph of U-shape

sensing yoke

Design of Magnetic Sensor for PVC

sensor sensing yoke

Photograph of the completed sensor front side (above) and rear side (bottom)

R11R12

R10

R8

R6

R9

R13

R7

R14

C18

1 n

C17

C20

C21

D2

DIODE

SIN COS

-

+

U-2A

4

13

2

-

+

U-2B

75

6

8

-

+

U-3A

13

2

8

+5VC19

104

+5V

Schematic diagram of the sensor system

Electronic Circuit of Magnetic Sensor

R20

R

R21

R

-

+

U5AD797

3

26

74

U6

D1

S12

GND3

+VCC4VCC5

IN6

-VCC7

S28

C41

R13

R26

R18

R25

R2210 Ω

R16

R14

R17

10 k

R15

R27

R32

R28

R33

R29

R34

5 k

R30

C29

C37

104

C32473

C39473C40

104

C33

104

C21

104C23

104

C25

104

C26

104

C30

104

C31

104

C35

104

C36

104

C27

104

C28

104

C34

104

C38

104

D3

DIODE

L1

1

2

L2

1

2

L3

1

2

4

-

+

U-4A

4

13

2

-

+

U-4B

75

6

8

-

+

U-5A

4

13

2

-

+

U-5B

75

6

8

-

+

U-6A

4

13

2

-

+

U-6B

75

6

8

C22

104

-5V

+5V

+5V

+5V

+5V

+5V

+5V

U7

D1

S12

GND3

+VCC4

VCC5

IN6

-VCC7

S28

+5V

-5V

-5V

-5V

-5V

-5V

-5V

-5V

-5V

R19

R24

R

R23

R

C24

OUT(X)

OUT(Y)

R1

20 kR210 k

R3

20 kR410 k

C1

104

C8

104

REF43

OUT(X)

OUT(Y)

REF43

U2

+Vcc1

CH02

CH13

CH24

CH35

COMM6

SHDN7

Vref8

+Vcc9

GND10

GND11

DOUT12BUSY13DIN14CS15

DIN16

-

+

U-1A

13

2

8

-

+

U-1B

4

75

6

C410 uF

C5104

DOUT

C210uF

C6104

C3104

DCLK

C7104

DIN

C10

01uF

CS

BUSY

C14 10uF

J1

CON6

123456

D1

DIODE

R5

47K

C9

10uF

C1310uF

Y1

OSC

OUT3

GND2

VCC4

U3

RSTVPP1

GND10

VCC20

XTAL15

XTAL24

P10AIN012P11AIN113P1214P1315P1416P1517P1618P1719

P30RXD2

P31TXD3

P32INT06

P33INT17

P34T08

P35T19

P3711

U4

C1+1

C1-3

C2+4

C2-5

VCC16

GND15

V+2

V-6

R1OUT12

R2OUT9

T1IN11

T2IN10

R1IN13

R2IN8

T1OUT14

T2OUT7

C12 10uF

C16

01uF

C15 10uF

C11

01uF

-5V

+5V

+5V

+5V

+5V

+5V

+5V

+5V

RST

OSC

OSC

RST

DCLKCSDINBUSYDOUT

U1

IN2

GND

4

OUT6

TEMP3

TRIM5

-5V

+5V

Electronic circuit diagram of the magnetic sensor

Photograph of the completed measuring system data acquisition

software in PC and probe scanning system

Experimental Setup for Magnetic Sensor

Reference material Scanning System Software LabVIEW

Reference Material (1) Normal defects and PVCs

Longitudinal and transverse defects

Def W L D Remarks

1 02 500 0213 (20 ) Inner defects

2 02 500 0427 (40 )

3 02 500 0213 (20 )Outer defectsPVC(1018)4 02 500 0427 (40 )

5 02 500 0639 (60 )

6 02 500 0852 (80 )

7 02 500 0639 (60 ) Inner defects

8 02 500 0852 (80 )

- 1 and 2 are inner defects

- 345 and 6 are outer defects with PVC

- 7 and 8 are inner defects

PVC

PVC

Defect Defect

For longitudinal defects and PVC For circumferential defects and PVC

ECT is very difficult to detect circumferential defects

We can distinguish PVCs and defects and longitudinal and circumferential defects

Flux-gate Magnetometer

One core sensor Two core sensor

3-축 flux-gate Magnetometer의 계략도

Sensorpia Co

pro

cess

or(

AV

R)

Sensor 1

RS422

Interface

Mic

ro-p

roce

ssor(

AV

R)

Sensor 2

Sensor 3

Interface

조립된 마그네토미터의 사진

Sensorpia Co

Analog PCB

Digital PCB

Sensorpia Co선형도(linearity)

10

20

30

40

50

60

y-axis

Magnetometer Output (microT)

-60 -50 -40 -30 -20 -10 0 10 20 30 40 50 60

-60

-50

-40

-30

-20

-10

0

10

Y-axis y=099946 x+0015STD 106E-4

Magnetometer Output (

Applied Magnetic Field (microT)

마그네토미터의 noise 특성 Sensorpia Co

1

10

100

y-axis

Magnetometer noise (nT)

0 1 2 3 4 5 6

1E-4

1E-3

001

01

Magnetometer noise (nT)

Frequency (Hz)

Magnetometer for KoDSAT

-150 -100 -50 0 50 100 150

-15

-10

-5

0

5

10

15

Magnetic Moment (Am

2)

Current (mA)

After Thermal Cycle Test

Measured

Resistance 193 ohm

Photograph of Magnetic torquer

Photograph of KoDSAT

Photograph of

3-axis Fluxgate

Magnetometer

Photograph of Magnetic torquer

Application of magnetometer

Moon magnetic fieldmeasurement

Telescope with direction indication

Joule Effect (Magnetostriction)

ϕ2cosel

l=

∆

0=∆

+∆

+∆

b

b

a

a

l

l

Actuator using Terfenol-D

00

05

10

B (T)

800

1000

1200

1400

1600

Magnetostriction (ppm)

-100 -50 0 50 100

-10

-05

00

B (T)

H (kAm)

2 MPa

4 MPa

6 MPa

8 MPa

10 MPa

12 MPa

-100 -50 0 50 100

-200

0

200

400

600

Magnetostriction (ppm)

H (kAm)

2 MPa

4 MPa

6 MPa

8 MPa

10 MPa

12 MPa

600

700

800

900

1000

-4 -3 -2 -1 0 1 2 3 4

0

10

20

30

40

50

60

Displacement (m

icro meter)

I (A)

FIELD

9 kAm

12 kAm

16 kAm

20 kAm

24 kAm

38 kAm

-50 -40 -30 -20 -10 0 10 20 30 40 50

-100

0

100

200

300

400

500

L (PPM)

H (kAm)

9 kAm

12 kAm

16 kAm

20 kAm

24 kAm

38 kAm

Magnetostrictive displacement sensor

Hysteresis loops under

tensile stress σ

(a) Crystalline 68 NiFe

λs = +25 10-6

(b) crystalline pure Ni λs

= -35 10-6

Villari Effect ( Inverse of Joule Effect)

= -35 10-6

(c) amorphous Co-based

alloy

λs = -35 10-6

ϕσλ 2sin2

3sdotsdot= smeE

γ

Permeability depending on the stress

σλmicromicro

1

3

2

Y

J

so

s

r =

γ

Calculated magnetization curves under stress

Variation of magnetization curve by an applied

tensile force (Co-based amorphous alloy)

Alloy Requirement

Materials for magnetoelastic sensors

Why amorphous magnetic materials are important

Stress-strain curves of several materials

Coercivity and hardness of several materials

Principles of magnetoelastic sensors

Non-contact torque sensor

Principle of cross torductor torque

sensor and flux pattern of sensor

poles on the surface of a shaft

a) without and b)with torsional load

Equivalent magnetic circuit of

cross type torque sensor

Helices of principal tensile and compressive stress on the surface of

a shaft subjected to torsion [32] Correlated changes of permeability

are detected by four-branch yoke system with sensing coils 123

and 4 and a common excitation pole

Examples of torque sensors

Four-branch type torque sensor

heads Pole structures realized

by commercial multi-pole

ferrites 14 and 18 min in

diameter (diameter of sensor

h e a d 1 7 a n d 2 4 m m

respectively) respectively)

Principle of Ring Torductor torque transducer

(a b) Physical structure (c) evolution of the

shaft surface under the transducer poles A and BRing torductor for measuring

torque on ship propeller shafts

(shaft diameter ca 500 mm)

(Courtesy ASEA Brown

Boveri AG)

Principal designs of coaxial torque sensors

Schematic diagram of data processing

electronics of a torque sensor

Extensometer (a) Construction of strain sensing element using

amorphous ribbon wound core (b) configuration of lumped

windings

∆E effect of an amorphous FeNi-based

alloy (Fe40 Ni38 Mo4 B18) Hs saturation

field

Magnetically tunable delay line

Torque Sensors using Amorphous wire

Sixtus tonk효과(large Barkhausen효과)

Hysteresis loops of a Wiegand wire for different reset fields

Curie 온도 및Hopkinson효과

Relation between normalised

saturation polarisation and

normalised Curie temperature

Permeability of a Mn-Zn ferrite as

a function of temperature and field

strength

Conclusions

1) Magnetic sensor 는 자동차 공장자동화 항공우주 및 군사용으로많이 사용되고 있다

2) 새로운 소재개발은 자기센서의 성능개발에 직접적인 영향을 준다2) 새로운 소재개발은 자기센서의 성능개발에 직접적인 영향을 준다

3) 센서의 개발을 위해서는 다양한 전공지식이 요구된다

(물리학 재료공학 기계공학 전자공학)

4) 센서분야가 고부가가치를 창출하는 부품사업이다

5) 핵심부품을 생산하는 중소기업의 item으로도 적절하다

Response Curves of the Sensors

Trends in Sensor Development

MEMS based sensorsBio-sensorsSmart and intelligent sensors Sensors for networkingSensors for home automation

Sensor in Automobiles

Definition of Magnetic Sensor

Sensors which are associated with the laws and effects of magnetic and electromagnetic fields

Why are Magnetic Sensors ImportantWhy are Magnetic Sensors Important

1) High reliability Military Flux-gate Search coil

Automobile ABS non-contact angle

Air and space Magnetic torquer Flux-gate

2) High Temperature LVDT Flux-gate

3) High radiation Eddy current probe and LVDT used in nuclear

power plant

Magnetic Effects for SensorsYear Effect Explanation Technical Use

1842 Joule effect Change in shape of a ferromagnetic body with magnetization (magnetostriction)

In combination with piezoelectric elements for magnetometers and potentiometers

1846 ΔE effect Chang in Youngrsquos modulus with magnetization Acoustic delay line components for magnetic field measurement

1847 Matteucci effect Torsion of a ferromagnetic rod in a longitudinal field changes magnetization

Magnetoelastic sensor

1856 Magnetoresistance

(AMR)

Change in resistance with magnetic field Magnetoresistive sensors

1858 Wiedemann effect A torsion is produced in a current carrying ferromagnetic rod when subjected to a longitudinal field

Torque and force measurement

1865 Villari effect Effect on magnetization by tensile or compressive strength

Magnetoelastic sensorsstrength

1879 Hall effect A current carrying crystal produces a transverse voltage when subjected to a magnetic field vertical to its surface

Magnetogalvanic sensors

1903 Skin effect Displacement of current from the interior of material to surface layer due to eddy currents

Distance sensors proximity sensors

1931 Sixtus Tonks effect Pulse magnetization by large Barkhausen jumps Wiegand and pulse-wire sensors

1962 Josephson effect Tunnel effect between two superconducting materials with an extremely thin separating layer quantum effect

SQUID magnetometers

1987 GMR effect Quantum mechanical magnetoresistance effect observed in thin-film structures composed of alternating ferromagnetic and non-magnetic conductive layers

Magnetic field sensor

Sprintonics

1994 GMI effect Large variations that the electrical impedance of some materials exhibits as a function of an external magnetic field

Magnetic field sensor

Principle of search coil type magnetometerPrinciple of search coil type magnetometer

int intint sdotminus=sdotA

ABt

sE d d

dd

Faradayrsquos Induction Law

Faraday 전자기유도법칙

Atd

HAnnU sdotsdotsdotsdot=Φsdotsdot= microωω max0

Voltage output from magnetometer

Sensitivity and Noise of Air Cored Induction Coil

HfDnHAnnU sdotsdotsdotsdotsdot=sdotsdotsdotsdot=Φsdotsdot= 02

2

0max02

microπ

microωω

2

022

00

microπ sdotsdot=

sdot=

Dn

Hf

US

V2π

sdotsdot=

sdotsdot

sdot= minus2

-970

m Hz nT

V10

m A

S V104πmicro

sdot

sdotsdot= minus

Hz nT

V10

2

922

0 DnUπ

Air-cored induction coil in a time-varying magnetic field

sdot

sdotsdot= minus

Hz nT

V10

2

922

0 DnUπ

Air-cored coil output voltage U0 at a magnetic field x frequency product

1 nT middot Hz versus diameter D with number of turns n as parameter

4

22 dDnWW

sdotsdotsdotsdot=

γπ Weight of coil

Coil resistance2

4

d

nDRDC

ρ=

Thermal voltage noisefTRU DCBN ∆= κ4

W

4W

DnfTU BN

sdotsdotsdotsdot∆=

πγρκ

fHnDdTk

DfHW

TkU

UNS

BBN

sdotsdotsdot

=sdotsdotsdot

== 21302

w00 )(28242

σmicroπ

γρmicroπ

Noise voltage

1028

ln286 9minussdot

+minus= αd

DDL

Equivalent circuit diagram of an air-cored induction coil

For single turn loop Dgtgtd

Long single layer solenoid

[H] 10 H][ 10 922

9222

minusminus sdotsdotsdot

=sdotsdotsdot

asympwd

nD

w

nDL

ππ

622

10 101 46

minussdot+sdot

asympwD

nDL

922

10 10 9 3

778 minussdot++sdot

asymphwD

nDL

Short single layer solenoid wgt16D

Multi-layer solenoid Dgtgtwh

( ) 1

370

ndc

DwC r

sdotminussdotsdotsdot

=ε

1

i

2tot minus+=k

C

k

CC

Capacitance C of a coil

Capacitance C of a single-layer coil normalized to

its diameter D versus length-to-diameter ratio wD

of the coil (capacitance C in pF and geometrical

dimensions w and D in cm)

12 minuskk

High permeability core induction coil

Magnetic field pattern around high permeability core

when it is inserted into a homogeneous field It is valid

for low frequencies and if the coil indicated at the middle

of the core is without current

Magnetization of a high permeability core

dt

dnu ci

i Φ

sdotminus= ) ( cosmaxc ci tωsdotΦ=Φ

ci0rc0 maxAHnnU sdotsdotsdotsdot=Φsdotsdot= micromicroωω

HNHHHH )1( minusminus=+= micro

HN

H sdotminus+

=)1(1

1

r

i micro

irdmi HNHHHH )1( minusminus=+= micro

HfAnU sdotsdotsdotsdotsdotsdot= 0cc0 2 micromicroπ

)1(1 r

rc minus+=

micromicro

microN

minus++

minusminus=

infin1)1ln(

11

1 2

22ell mmm

m

mN

10326) (1ln 152

10156) (1ln 262

ell

cyl

++++

=infin

infin

N

N

Induction coil on a cylindrical high permeability core

Demagnetization factorDemagnetization factorN of prolate ellipsoidsand cylindrical rods(descending curves) andcore permeability μc

(ascending curves) ofcylindrical rods versusthe length-to-diameterratio m of the rod withmaterial permeability μr

as parameter

Core permeability μc of cylindrical rods versus thematerial permeability μr with length-to-diameter ratiom of the rod as parameter after

Minimum noise equivalent magnetic field spectral density of an induction coil sensor with high permeability core versus sensor weight Ws (at length-to-diameter ratios m = 50 and 100 permeability μr = 10000 of the core material and f = 1 Hz)

Induction coil sensors with electronic amplifier

II

rKLC

1=ω

II

II

RR

RK

+=

rr

2 i 1

)(

ωω

ωω

ω

D

KF

+

minus

=

+=

II

II

II

2

C

L

R

R

C

L

KD

Frequency responses of the search coil

Frequency responses of thesensitivity SA and the output voltage UA

of an induction coil sensor with a voltageamplifier at a constant magnetic fieldamplitude

Resonance step-up of thesensitivity SA at differentvalues of the damping D

Sensor with transformer coupled negative feedback to the coil

)(i)()(F

0 ωωωω FR

UMUAU A

A sdot

minus=

)( i1

)(

F

0

ωω

ω

FR

MA

FAUU A

sdot+

sdot=

Induction coil connected to a voltage amplifier with

transformer coupled negative feedback to the coil

FR

21

1K0

i1

1

i1

i )(

ωωωωωω

ωω

+sdot

+sdot=

M

RUU A

IIF2 CRL

MAf

sdotsdotsdotsdot

=∆π

Frequency response of the output voltage UA of an induction coil sensor with negative feedback transformer coupled to the coil

Applications of search coil magnetometer

Developed search coil magnetometer using amorphous ribbon

Experimental setup for the effective permeability measurement

Relative permeability depending on the numbers of ribbon(a)

and the air gap between ribbons

Relative permeability depending on the number of ribbons for the different air gap between ribbons

Relative permeability depending on the total number of ribbons for the different air gap between ribbons

10 pT

100 pT

1 pT

Noise spectrum of the developed search coil magnetometer

BJne

E xH

1minus=

neRH

1minus=

22 nP micromicro minus

Hall 효과

Bt

IRU H

HL =

2

22

)( he

eh

Hpne

nPR

micromicromicromicro

+

minus=

Rectangular Hall plate (cc1cc2 current constant sc1sc2

sensor constant I bias current U voltage drop UH Hall

voltage

Physics carrier concentration and kind of carrier measurement

Engineering magnetic field measurement

Current Measurement

Arrangement for noninvasive

current measurement using an iron

core The current to be measured

produces a proportional magnetic

field which can be measured in the

air gap

Characteristic curve produced by

the current

Arrangement for indirect noninvasive

current measurement using the

compensation principle An iron core as

represented in Figure 3-29 is held field

free by injection a current into a

compensating coil wound on the core

which offsets the field generated by the

current being measured The Hall effect

sensor in the air gap serves as a null

indicator

Circuit diagram for AC-power

measurement using a Hall effect

sensor

DC Power Measurement

Circuit diagram for DC-

power measurement using a

Hall effect sensor

Noncontact Position Sensing

Galvanomagnetic components for sensing the position of permanent magnets

and magnetically conductive materials

Current Sensor Based on Hall Sensor

and Magnetic Core for Hybrid Vehicle

KH Yeon1 SD Kim1 and D Son2 1Auto industry co14F Hanshin IT tower Guro Gu Seoul Korea2Hannam UniversityOjung dong 133 Daejeon Rep of Korea

i

Hall sensor

B

I

SB

ring core

B

I10

g

N

Bl S

micro

)( gtgtrmicro

gab core

Current Sensor Based on Hall

Sensor and Magnetic Core

Hall

Effect

Device

CurrentVoltage

applying for

Hall effect device

operation

Output

signals

Magnetic field

Occurred by

current measurement

Signal

process

circuits

Developed Current Sensor

Magnetic core

Hall sensor

PCB

25

30

35

40

45

50

Output voltage V

Current sensor(Open loop type)

Temp 25C

400A model

+400 ~ -400A

SD 000128

Linearity 003

Linearity of the sensor

Characteristics of the Current Sensors

1000A 10 V power supply

-500 -400 -300 -200 -100 0 100 200 300 400 500

00

05

10

15

20

Output voltage V

current A

Temperature 25Linearity 003

Measuring range -400A ~ +400A

1000A Electronic Load

-3

0

3

6

9

12

15

18

dB

Current sensor

DV2 PCB 24pF

40Aturns

Frequency bandwidth

Gain bandwidth 3 MHz

Current 10 A

Temperature 25

Frequency bandwidth 100 kHz

Sensor output voltage vs frequency

at applied current of 40 Aturns

1 10 100

-18

-15

-12

-9

-6

Frequency kHz 측정온도 25

주파수특성 30kHz 이상(3dB 기준)

측정전류 40Aturns(4A 10턴)

측정주파수 100Hz ~ 100kHz

Temperature 25Current 40Aturns

Frequency range 100 Hz ~ 100 kHz

What is Magnetoresistance

Magnetoresistance effect(AMR)

θθθ 2cos2

12sin12cos(

22 minusminus+∆asymp∆ xxxmx hhhRR

32 minusasymp∆ ρρ New effect GMR CMR and GMI

10 ge∆ ρρ

Two bridge configuration for

rotational angle measurement

measurement angle more than 180o

자동차 Engine Management System

Inductive and Eddy Current

Sensors Excited by Permanent Magnets

tNtU dd)( φsdotminus=

construction of an inductive

sensor (courtesy VDO Adolf sensor (courtesy VDO Adolf

Schindling AG)

1) constant socket

2) terminal package

3) permanent magnet

4) cap

5) soft magnetic core

6) coil

7) plate

8) blade connector

γγ

Sensor with yoke Change in the magnetic flux with

varying air gap Continuous lines

minimum air gap dashed lines

maximum air gap

C-shaped sensor

Sensor with radially

magnetized

permanent magnet

Signal Conditioning

Output voltage U of a DC-excited sensor with permanent

magnets when a single iron object passes by

Schematic electrical diagram of an inductive sensor

Linear Variable Differential Transformer

AC-Excited Sensors for Linear Movement

Principle of construction of an LVDT

Electrical circuit of an LVDT

tIMtNU dd dd sdotminus=sdotminus= φ

tIMtIMUUU dd dd 1212 sdotminussdot=minus=

tIMMU dd)( 12 sdotminus=

)(12 xMMMM =minus=

tIxMU dd)( sdot= tI

UxM

dd)( =

Signal Conditioning

power supply

carrier gen

autoampcontrol

LVDTcarrieramp

demod-ulator

phase

shifter

power supply

carrier gen

passivedemod-ulator

LVDTDCamp

Block diagram of a carrier amplifier system

Block diagram of a DC amplifier system

Variable Inductive Sensors

Principle of construction

of the VLP sensor

Principle of a bridge

circuit

lANL r 20 sdotsdotsdot= micromicro

21 BA UUU minus=

21)i(ii( 211 minus+sdot= LLLUU BA ωωω

)21))()((( minus∆minus+∆+∆+sdot= LLLLLLUU BA

)212)(( minus∆+sdot= LLLUU )212)(( minus∆+sdot= LLLUU BA

LLUU BA 21 ∆sdotsdot=

llLL ∆sdot=∆ d d

llLLUU BA ∆sdotsdot= d d)2(1

Applications and Properties

Principle of a construction of a force transducer

(courtesy Hottinger Baldwin Messtechnik)

Vibrationacceleration sensor

Signal Conditioning

Schematic electrical diagram of a force transducer connected with an

amplifier (courtesy Hottinger Baldwin Messtechnik GmbH)

Variable Gap Sensors

)( FeFe2

0 LLllANL micromicromicro +sdotsdot=

FeFe2

0max lANL sdotsdotsdot= micromicro

Construction of a variable gap sensor

Characteristic of a variable gap sensor

Construction of a differential

cross-anchor sensor

Output voltage U versus core

position x plusmn a limits of the

linear rage

Applications of differential cross-anchor sensors

AC-excited Sensors for Rotary Movements

Principle of construction of a synchro

α cos10 sdotsdot= UKU y

)120-( cos10 degsdotsdot= αUKU z

)240-( cos10 degsdotsdot= αUKU x

)120-( sin3100 degsdotsdotsdot=minus= αKUUUU yxyx

)240-( sin3100 degsdotsdotsdot=minus= αKUUUU zyzy

α sin3100 sdotsdotsdot=minus= KUUUU xzxz

Application to the Torque Sensor

Principle of construction of a torque-type synchro

Torque versus angular

difference

)( sin~ rt αα minussdotKM

)( cos~ rt1r αα minussdotUU

Principle of construction of a control-type sensor

Output voltage versus

angular difference

Principle of construction of a differential sychro

Eddy Current Sensors

tBE dd curl minus=JH = curl

0 div =BH(H)B sdot= micro

E(E)J sdot= σ

A B curl= A B curl=

tdd- A E =

)dd( tAJ minus= σ

tdd curl curl AA σmicro minus=

AA) σωmicro iminus= curl )(curl(1

AA) σωmicro i=∆)((1

Eddy Current Tachometer

Construction of a speedometer (courtesy VDO Adolf Schinding AG) 1) spindle 2) bearing

3) holding spring 4) iron yoke 5) eddy current cup 6) shaft of the magnet 7) support of

the magnet 8) temperature compensation 9) permanent magnet 10) torsion spring

Proximity Sensors

Schematic diagram of a proximity sensor

Output current of a proximity switch versus distance

Inductive Flowmeters

)( Btimessdot= υqF

EqF sdot=BE times=υ

)(ds Btimes== υEU )(ds Btimes== υEU

)( Bd timessdot= υU

Bsdotsdotsdot= υdKU

Development of magnetic phase detection

sensor for steam generator tube

Dirac Son1 Kwan-Sang Ryu2 Duck-Gun Park3

1Hannam University Daejeon Rep of Korea2Korea Research Institute of Standards and Science Daejeon Rep of Korea3KoreaAtomic Energy Research Institute Daejeon Rep of Korea

Introduction

The layout of pressurized water reactor (PWR) components

Primary side Secondary side (non-radioactive side)(radioactive side)

The Structure of SG(Steam Generator)(degradation mechanism)

Secondary SidePrimary Side

SCC

A B

A-B

Steam outlet

Anti-vibration

SCC

Fretting

Wall thinning

IGA

U-bend

In commercial power plants SG- height up to 21 m - weight up to 800 tons - 2~4 sets of SG were installed - SG can contain from 3000 to

16000 tubes each about 20 mmin diameter

Primary coolant outlet Primary coolant inlet

Anti-vibrationbars

Tubesupportplate

Tubesheet

IGA

SCC

Pitting

SCC

Inside Tubesheet

Top of Tubesheet

by SSHwang of KAERI

Denting

Sludge pile

in diameter

The SGT is made of nickel basedInconel alloy which is composed of 75 Ni 165Cr and 815Fe

-Degradation mechanism corrosion pitting denting inter granular attack

-Inspection Eddy current Testing(ECT)

Permeability Variation Clusters (PVC)

(Ferro-magnetic phase)

-005

000

005

010

015

m (emug)

1-1

-002

000

002

004

006

008

m (emug)

1-2

-1000 -500 0 500 1000

-015

-010

-005

H ( Am )

-1000 -500 0 500 1000

-006

-004

-002

H ( Am )

The hystresis loop in the fragment of PVC parts of Kori-1 retired SG tube

-004

-002

000

002

004

006

M (emug)

Inconel 600 tested at RT

under tensile stress

1 2 3

4 5 6

7 8 9-004

-002

000

002

004

006

M(emug)

Inconel 600 Heat treated at

602 oC under tensile stress

1 2 3

How can we detect magnetic phase

(PVC)selectively from the flaws in SGT

-3000 -2000 -1000 0 1000 2000 3000

-006

H (Oe)

7 8 9

10 11 12

-3000 -2000 -1000 0 1000 2000 3000

-006

-004

H(Oe)

4 5 6

7 8 9

The hysteresis loop of the tensile tested specimen at room temperature (a) and tensile tested at high temperature (b)

The magnetic phase can be created under the high temperature andpressure conditions which is correspond to the stress corrosion crackingin the SG tube in the NPP(Bruemmer SM Charlot LA amp Henager CH (1988) Corrosion 782)

Principle of ECT

If we can separate magnetic phase selectively from the

flaws using magnetic sensor the reliability of EC in SGT

inspection will be greatly enhanced

Structure of the permeability

sensor

Dimension and photograph of U-shape

sensing yoke

Design of Magnetic Sensor for PVC

sensor sensing yoke

Photograph of the completed sensor front side (above) and rear side (bottom)

R11R12

R10

R8

R6

R9

R13

R7

R14

C18

1 n

C17

C20

C21

D2

DIODE

SIN COS

-

+

U-2A

4

13

2

-

+

U-2B

75

6

8

-

+

U-3A

13

2

8

+5VC19

104

+5V

Schematic diagram of the sensor system

Electronic Circuit of Magnetic Sensor

R20

R

R21

R

-

+

U5AD797

3

26

74

U6

D1

S12

GND3

+VCC4VCC5

IN6

-VCC7

S28

C41

R13

R26

R18

R25

R2210 Ω

R16

R14

R17

10 k

R15

R27

R32

R28

R33

R29

R34

5 k

R30

C29

C37

104

C32473

C39473C40

104

C33

104

C21

104C23

104

C25

104

C26

104

C30

104

C31

104

C35

104

C36

104

C27

104

C28

104

C34

104

C38

104

D3

DIODE

L1

1

2

L2

1

2

L3

1

2

4

-

+

U-4A

4

13

2

-

+

U-4B

75

6

8

-

+

U-5A

4

13

2

-

+

U-5B

75

6

8

-

+

U-6A

4

13

2

-

+

U-6B

75

6

8

C22

104

-5V

+5V

+5V

+5V

+5V

+5V

+5V

U7

D1

S12

GND3

+VCC4

VCC5

IN6

-VCC7

S28

+5V

-5V

-5V

-5V

-5V

-5V

-5V

-5V

-5V

R19

R24

R

R23

R

C24

OUT(X)

OUT(Y)

R1

20 kR210 k

R3

20 kR410 k

C1

104

C8

104

REF43

OUT(X)

OUT(Y)

REF43

U2

+Vcc1

CH02

CH13

CH24

CH35

COMM6

SHDN7

Vref8

+Vcc9

GND10

GND11

DOUT12BUSY13DIN14CS15

DIN16

-

+

U-1A

13

2

8

-

+

U-1B

4

75

6

C410 uF

C5104

DOUT

C210uF

C6104

C3104

DCLK

C7104

DIN

C10

01uF

CS

BUSY

C14 10uF

J1

CON6

123456

D1

DIODE

R5

47K

C9

10uF

C1310uF

Y1

OSC

OUT3

GND2

VCC4

U3

RSTVPP1

GND10

VCC20

XTAL15

XTAL24

P10AIN012P11AIN113P1214P1315P1416P1517P1618P1719

P30RXD2

P31TXD3

P32INT06

P33INT17

P34T08

P35T19

P3711

U4

C1+1

C1-3

C2+4

C2-5

VCC16

GND15

V+2

V-6

R1OUT12

R2OUT9

T1IN11

T2IN10

R1IN13

R2IN8

T1OUT14

T2OUT7

C12 10uF

C16

01uF

C15 10uF

C11

01uF

-5V

+5V

+5V

+5V

+5V

+5V

+5V

+5V

RST

OSC

OSC

RST

DCLKCSDINBUSYDOUT

U1

IN2

GND

4

OUT6

TEMP3

TRIM5

-5V

+5V

Electronic circuit diagram of the magnetic sensor

Photograph of the completed measuring system data acquisition

software in PC and probe scanning system

Experimental Setup for Magnetic Sensor

Reference material Scanning System Software LabVIEW

Reference Material (1) Normal defects and PVCs

Longitudinal and transverse defects

Def W L D Remarks

1 02 500 0213 (20 ) Inner defects

2 02 500 0427 (40 )

3 02 500 0213 (20 )Outer defectsPVC(1018)4 02 500 0427 (40 )

5 02 500 0639 (60 )

6 02 500 0852 (80 )

7 02 500 0639 (60 ) Inner defects

8 02 500 0852 (80 )

- 1 and 2 are inner defects

- 345 and 6 are outer defects with PVC

- 7 and 8 are inner defects

PVC

PVC

Defect Defect

For longitudinal defects and PVC For circumferential defects and PVC

ECT is very difficult to detect circumferential defects

We can distinguish PVCs and defects and longitudinal and circumferential defects

Flux-gate Magnetometer

One core sensor Two core sensor

3-축 flux-gate Magnetometer의 계략도

Sensorpia Co

pro

cess

or(

AV

R)

Sensor 1

RS422

Interface

Mic

ro-p

roce

ssor(

AV

R)

Sensor 2

Sensor 3

Interface

조립된 마그네토미터의 사진

Sensorpia Co

Analog PCB

Digital PCB

Sensorpia Co선형도(linearity)

10

20

30

40

50

60

y-axis

Magnetometer Output (microT)

-60 -50 -40 -30 -20 -10 0 10 20 30 40 50 60

-60

-50

-40

-30

-20

-10

0

10

Y-axis y=099946 x+0015STD 106E-4

Magnetometer Output (

Applied Magnetic Field (microT)

마그네토미터의 noise 특성 Sensorpia Co

1

10

100

y-axis

Magnetometer noise (nT)

0 1 2 3 4 5 6

1E-4

1E-3

001

01

Magnetometer noise (nT)

Frequency (Hz)

Magnetometer for KoDSAT

-150 -100 -50 0 50 100 150

-15

-10

-5

0

5

10

15

Magnetic Moment (Am

2)

Current (mA)

After Thermal Cycle Test

Measured

Resistance 193 ohm

Photograph of Magnetic torquer

Photograph of KoDSAT

Photograph of

3-axis Fluxgate

Magnetometer

Photograph of Magnetic torquer

Application of magnetometer

Moon magnetic fieldmeasurement

Telescope with direction indication

Joule Effect (Magnetostriction)

ϕ2cosel

l=

∆

0=∆

+∆

+∆

b

b

a

a

l

l

Actuator using Terfenol-D

00

05

10

B (T)

800

1000

1200

1400

1600

Magnetostriction (ppm)

-100 -50 0 50 100

-10

-05

00

B (T)

H (kAm)

2 MPa

4 MPa

6 MPa

8 MPa

10 MPa

12 MPa

-100 -50 0 50 100

-200

0

200

400

600

Magnetostriction (ppm)

H (kAm)

2 MPa

4 MPa

6 MPa

8 MPa

10 MPa

12 MPa

600

700

800

900

1000

-4 -3 -2 -1 0 1 2 3 4

0

10

20

30

40

50

60

Displacement (m

icro meter)

I (A)

FIELD

9 kAm

12 kAm

16 kAm

20 kAm

24 kAm

38 kAm

-50 -40 -30 -20 -10 0 10 20 30 40 50

-100

0

100

200

300

400

500

L (PPM)

H (kAm)

9 kAm

12 kAm

16 kAm

20 kAm

24 kAm

38 kAm

Magnetostrictive displacement sensor

Hysteresis loops under

tensile stress σ

(a) Crystalline 68 NiFe

λs = +25 10-6

(b) crystalline pure Ni λs

= -35 10-6

Villari Effect ( Inverse of Joule Effect)

= -35 10-6

(c) amorphous Co-based

alloy

λs = -35 10-6

ϕσλ 2sin2

3sdotsdot= smeE

γ

Permeability depending on the stress

σλmicromicro

1

3

2

Y

J

so

s

r =

γ

Calculated magnetization curves under stress

Variation of magnetization curve by an applied

tensile force (Co-based amorphous alloy)

Alloy Requirement

Materials for magnetoelastic sensors

Why amorphous magnetic materials are important

Stress-strain curves of several materials

Coercivity and hardness of several materials

Principles of magnetoelastic sensors

Non-contact torque sensor

Principle of cross torductor torque

sensor and flux pattern of sensor

poles on the surface of a shaft

a) without and b)with torsional load

Equivalent magnetic circuit of

cross type torque sensor

Helices of principal tensile and compressive stress on the surface of

a shaft subjected to torsion [32] Correlated changes of permeability

are detected by four-branch yoke system with sensing coils 123

and 4 and a common excitation pole

Examples of torque sensors

Four-branch type torque sensor

heads Pole structures realized

by commercial multi-pole

ferrites 14 and 18 min in

diameter (diameter of sensor

h e a d 1 7 a n d 2 4 m m

respectively) respectively)

Principle of Ring Torductor torque transducer

(a b) Physical structure (c) evolution of the

shaft surface under the transducer poles A and BRing torductor for measuring

torque on ship propeller shafts

(shaft diameter ca 500 mm)

(Courtesy ASEA Brown

Boveri AG)

Principal designs of coaxial torque sensors

Schematic diagram of data processing

electronics of a torque sensor

Extensometer (a) Construction of strain sensing element using

amorphous ribbon wound core (b) configuration of lumped

windings

∆E effect of an amorphous FeNi-based

alloy (Fe40 Ni38 Mo4 B18) Hs saturation

field

Magnetically tunable delay line

Torque Sensors using Amorphous wire

Sixtus tonk효과(large Barkhausen효과)

Hysteresis loops of a Wiegand wire for different reset fields

Curie 온도 및Hopkinson효과

Relation between normalised

saturation polarisation and

normalised Curie temperature

Permeability of a Mn-Zn ferrite as

a function of temperature and field

strength

Conclusions

1) Magnetic sensor 는 자동차 공장자동화 항공우주 및 군사용으로많이 사용되고 있다

2) 새로운 소재개발은 자기센서의 성능개발에 직접적인 영향을 준다2) 새로운 소재개발은 자기센서의 성능개발에 직접적인 영향을 준다

3) 센서의 개발을 위해서는 다양한 전공지식이 요구된다

(물리학 재료공학 기계공학 전자공학)

4) 센서분야가 고부가가치를 창출하는 부품사업이다

5) 핵심부품을 생산하는 중소기업의 item으로도 적절하다

Trends in Sensor Development

MEMS based sensorsBio-sensorsSmart and intelligent sensors Sensors for networkingSensors for home automation

Sensor in Automobiles

Definition of Magnetic Sensor

Sensors which are associated with the laws and effects of magnetic and electromagnetic fields

Why are Magnetic Sensors ImportantWhy are Magnetic Sensors Important

1) High reliability Military Flux-gate Search coil

Automobile ABS non-contact angle

Air and space Magnetic torquer Flux-gate

2) High Temperature LVDT Flux-gate

3) High radiation Eddy current probe and LVDT used in nuclear

power plant

Magnetic Effects for SensorsYear Effect Explanation Technical Use

1842 Joule effect Change in shape of a ferromagnetic body with magnetization (magnetostriction)

In combination with piezoelectric elements for magnetometers and potentiometers

1846 ΔE effect Chang in Youngrsquos modulus with magnetization Acoustic delay line components for magnetic field measurement

1847 Matteucci effect Torsion of a ferromagnetic rod in a longitudinal field changes magnetization

Magnetoelastic sensor

1856 Magnetoresistance

(AMR)

Change in resistance with magnetic field Magnetoresistive sensors

1858 Wiedemann effect A torsion is produced in a current carrying ferromagnetic rod when subjected to a longitudinal field

Torque and force measurement

1865 Villari effect Effect on magnetization by tensile or compressive strength

Magnetoelastic sensorsstrength

1879 Hall effect A current carrying crystal produces a transverse voltage when subjected to a magnetic field vertical to its surface

Magnetogalvanic sensors

1903 Skin effect Displacement of current from the interior of material to surface layer due to eddy currents

Distance sensors proximity sensors

1931 Sixtus Tonks effect Pulse magnetization by large Barkhausen jumps Wiegand and pulse-wire sensors

1962 Josephson effect Tunnel effect between two superconducting materials with an extremely thin separating layer quantum effect

SQUID magnetometers

1987 GMR effect Quantum mechanical magnetoresistance effect observed in thin-film structures composed of alternating ferromagnetic and non-magnetic conductive layers

Magnetic field sensor

Sprintonics

1994 GMI effect Large variations that the electrical impedance of some materials exhibits as a function of an external magnetic field

Magnetic field sensor

Principle of search coil type magnetometerPrinciple of search coil type magnetometer

int intint sdotminus=sdotA

ABt

sE d d

dd

Faradayrsquos Induction Law

Faraday 전자기유도법칙

Atd

HAnnU sdotsdotsdotsdot=Φsdotsdot= microωω max0

Voltage output from magnetometer

Sensitivity and Noise of Air Cored Induction Coil

HfDnHAnnU sdotsdotsdotsdotsdot=sdotsdotsdotsdot=Φsdotsdot= 02

2

0max02

microπ

microωω

2

022

00

microπ sdotsdot=

sdot=

Dn

Hf

US

V2π

sdotsdot=

sdotsdot

sdot= minus2

-970

m Hz nT

V10

m A

S V104πmicro

sdot

sdotsdot= minus

Hz nT

V10

2

922

0 DnUπ

Air-cored induction coil in a time-varying magnetic field

sdot

sdotsdot= minus

Hz nT

V10

2

922

0 DnUπ

Air-cored coil output voltage U0 at a magnetic field x frequency product

1 nT middot Hz versus diameter D with number of turns n as parameter

4

22 dDnWW

sdotsdotsdotsdot=

γπ Weight of coil

Coil resistance2

4

d

nDRDC

ρ=

Thermal voltage noisefTRU DCBN ∆= κ4

W

4W

DnfTU BN

sdotsdotsdotsdot∆=

πγρκ

fHnDdTk

DfHW

TkU

UNS

BBN

sdotsdotsdot

=sdotsdotsdot

== 21302

w00 )(28242

σmicroπ

γρmicroπ

Noise voltage

1028

ln286 9minussdot

+minus= αd

DDL

Equivalent circuit diagram of an air-cored induction coil

For single turn loop Dgtgtd

Long single layer solenoid

[H] 10 H][ 10 922

9222

minusminus sdotsdotsdot

=sdotsdotsdot

asympwd

nD

w

nDL

ππ

622

10 101 46

minussdot+sdot

asympwD

nDL

922

10 10 9 3

778 minussdot++sdot

asymphwD

nDL

Short single layer solenoid wgt16D

Multi-layer solenoid Dgtgtwh

( ) 1

370

ndc

DwC r

sdotminussdotsdotsdot

=ε

1

i

2tot minus+=k

C

k

CC

Capacitance C of a coil

Capacitance C of a single-layer coil normalized to

its diameter D versus length-to-diameter ratio wD

of the coil (capacitance C in pF and geometrical

dimensions w and D in cm)

12 minuskk

High permeability core induction coil

Magnetic field pattern around high permeability core

when it is inserted into a homogeneous field It is valid

for low frequencies and if the coil indicated at the middle

of the core is without current

Magnetization of a high permeability core

dt

dnu ci

i Φ

sdotminus= ) ( cosmaxc ci tωsdotΦ=Φ

ci0rc0 maxAHnnU sdotsdotsdotsdot=Φsdotsdot= micromicroωω

HNHHHH )1( minusminus=+= micro

HN

H sdotminus+

=)1(1

1

r

i micro

irdmi HNHHHH )1( minusminus=+= micro

HfAnU sdotsdotsdotsdotsdotsdot= 0cc0 2 micromicroπ

)1(1 r

rc minus+=

micromicro

microN

minus++

minusminus=

infin1)1ln(

11

1 2

22ell mmm

m

mN

10326) (1ln 152

10156) (1ln 262

ell

cyl

++++

=infin

infin

N

N

Induction coil on a cylindrical high permeability core

Demagnetization factorDemagnetization factorN of prolate ellipsoidsand cylindrical rods(descending curves) andcore permeability μc

(ascending curves) ofcylindrical rods versusthe length-to-diameterratio m of the rod withmaterial permeability μr

as parameter

Core permeability μc of cylindrical rods versus thematerial permeability μr with length-to-diameter ratiom of the rod as parameter after

Minimum noise equivalent magnetic field spectral density of an induction coil sensor with high permeability core versus sensor weight Ws (at length-to-diameter ratios m = 50 and 100 permeability μr = 10000 of the core material and f = 1 Hz)

Induction coil sensors with electronic amplifier

II

rKLC

1=ω

II

II

RR

RK

+=

rr

2 i 1

)(

ωω

ωω

ω

D

KF

+

minus

=

+=

II

II

II

2

C

L

R

R

C

L

KD

Frequency responses of the search coil

Frequency responses of thesensitivity SA and the output voltage UA

of an induction coil sensor with a voltageamplifier at a constant magnetic fieldamplitude

Resonance step-up of thesensitivity SA at differentvalues of the damping D

Sensor with transformer coupled negative feedback to the coil

)(i)()(F

0 ωωωω FR

UMUAU A

A sdot

minus=

)( i1

)(

F

0

ωω

ω

FR

MA

FAUU A

sdot+

sdot=

Induction coil connected to a voltage amplifier with

transformer coupled negative feedback to the coil

FR

21

1K0

i1

1

i1

i )(

ωωωωωω

ωω

+sdot

+sdot=

M

RUU A

IIF2 CRL

MAf

sdotsdotsdotsdot

=∆π

Frequency response of the output voltage UA of an induction coil sensor with negative feedback transformer coupled to the coil

Applications of search coil magnetometer

Developed search coil magnetometer using amorphous ribbon

Experimental setup for the effective permeability measurement

Relative permeability depending on the numbers of ribbon(a)

and the air gap between ribbons

Relative permeability depending on the number of ribbons for the different air gap between ribbons

Relative permeability depending on the total number of ribbons for the different air gap between ribbons

10 pT

100 pT

1 pT

Noise spectrum of the developed search coil magnetometer

BJne

E xH

1minus=

neRH

1minus=

22 nP micromicro minus

Hall 효과

Bt

IRU H

HL =

2

22

)( he

eh

Hpne

nPR

micromicromicromicro

+

minus=

Rectangular Hall plate (cc1cc2 current constant sc1sc2

sensor constant I bias current U voltage drop UH Hall

voltage

Physics carrier concentration and kind of carrier measurement

Engineering magnetic field measurement

Current Measurement

Arrangement for noninvasive

current measurement using an iron

core The current to be measured

produces a proportional magnetic

field which can be measured in the

air gap

Characteristic curve produced by

the current

Arrangement for indirect noninvasive

current measurement using the

compensation principle An iron core as

represented in Figure 3-29 is held field

free by injection a current into a

compensating coil wound on the core

which offsets the field generated by the

current being measured The Hall effect

sensor in the air gap serves as a null

indicator

Circuit diagram for AC-power

measurement using a Hall effect

sensor

DC Power Measurement

Circuit diagram for DC-

power measurement using a

Hall effect sensor

Noncontact Position Sensing

Galvanomagnetic components for sensing the position of permanent magnets

and magnetically conductive materials

Current Sensor Based on Hall Sensor

and Magnetic Core for Hybrid Vehicle

KH Yeon1 SD Kim1 and D Son2 1Auto industry co14F Hanshin IT tower Guro Gu Seoul Korea2Hannam UniversityOjung dong 133 Daejeon Rep of Korea

i

Hall sensor

B

I

SB

ring core

B

I10

g

N

Bl S

micro

)( gtgtrmicro

gab core

Current Sensor Based on Hall

Sensor and Magnetic Core

Hall

Effect

Device

CurrentVoltage

applying for

Hall effect device

operation

Output

signals

Magnetic field

Occurred by

current measurement

Signal

process

circuits

Developed Current Sensor

Magnetic core

Hall sensor

PCB

25

30

35

40

45

50

Output voltage V

Current sensor(Open loop type)

Temp 25C

400A model

+400 ~ -400A

SD 000128

Linearity 003

Linearity of the sensor

Characteristics of the Current Sensors

1000A 10 V power supply

-500 -400 -300 -200 -100 0 100 200 300 400 500

00

05

10

15

20

Output voltage V

current A

Temperature 25Linearity 003

Measuring range -400A ~ +400A

1000A Electronic Load

-3

0

3

6

9

12

15

18

dB

Current sensor

DV2 PCB 24pF

40Aturns

Frequency bandwidth

Gain bandwidth 3 MHz

Current 10 A

Temperature 25

Frequency bandwidth 100 kHz

Sensor output voltage vs frequency

at applied current of 40 Aturns

1 10 100

-18

-15

-12

-9

-6

Frequency kHz 측정온도 25

주파수특성 30kHz 이상(3dB 기준)

측정전류 40Aturns(4A 10턴)

측정주파수 100Hz ~ 100kHz

Temperature 25Current 40Aturns

Frequency range 100 Hz ~ 100 kHz

What is Magnetoresistance

Magnetoresistance effect(AMR)

θθθ 2cos2

12sin12cos(

22 minusminus+∆asymp∆ xxxmx hhhRR

32 minusasymp∆ ρρ New effect GMR CMR and GMI

10 ge∆ ρρ

Two bridge configuration for

rotational angle measurement

measurement angle more than 180o

자동차 Engine Management System

Inductive and Eddy Current

Sensors Excited by Permanent Magnets

tNtU dd)( φsdotminus=

construction of an inductive

sensor (courtesy VDO Adolf sensor (courtesy VDO Adolf

Schindling AG)

1) constant socket

2) terminal package

3) permanent magnet

4) cap

5) soft magnetic core

6) coil

7) plate

8) blade connector

γγ

Sensor with yoke Change in the magnetic flux with

varying air gap Continuous lines

minimum air gap dashed lines

maximum air gap

C-shaped sensor

Sensor with radially

magnetized

permanent magnet

Signal Conditioning

Output voltage U of a DC-excited sensor with permanent

magnets when a single iron object passes by

Schematic electrical diagram of an inductive sensor

Linear Variable Differential Transformer

AC-Excited Sensors for Linear Movement

Principle of construction of an LVDT

Electrical circuit of an LVDT

tIMtNU dd dd sdotminus=sdotminus= φ

tIMtIMUUU dd dd 1212 sdotminussdot=minus=

tIMMU dd)( 12 sdotminus=

)(12 xMMMM =minus=

tIxMU dd)( sdot= tI

UxM

dd)( =

Signal Conditioning

power supply

carrier gen

autoampcontrol

LVDTcarrieramp

demod-ulator

phase

shifter

power supply

carrier gen

passivedemod-ulator

LVDTDCamp

Block diagram of a carrier amplifier system

Block diagram of a DC amplifier system

Variable Inductive Sensors

Principle of construction

of the VLP sensor

Principle of a bridge

circuit

lANL r 20 sdotsdotsdot= micromicro

21 BA UUU minus=

21)i(ii( 211 minus+sdot= LLLUU BA ωωω

)21))()((( minus∆minus+∆+∆+sdot= LLLLLLUU BA

)212)(( minus∆+sdot= LLLUU )212)(( minus∆+sdot= LLLUU BA

LLUU BA 21 ∆sdotsdot=

llLL ∆sdot=∆ d d

llLLUU BA ∆sdotsdot= d d)2(1

Applications and Properties

Principle of a construction of a force transducer

(courtesy Hottinger Baldwin Messtechnik)

Vibrationacceleration sensor

Signal Conditioning

Schematic electrical diagram of a force transducer connected with an

amplifier (courtesy Hottinger Baldwin Messtechnik GmbH)

Variable Gap Sensors

)( FeFe2

0 LLllANL micromicromicro +sdotsdot=

FeFe2

0max lANL sdotsdotsdot= micromicro

Construction of a variable gap sensor

Characteristic of a variable gap sensor

Construction of a differential

cross-anchor sensor

Output voltage U versus core

position x plusmn a limits of the

linear rage

Applications of differential cross-anchor sensors

AC-excited Sensors for Rotary Movements

Principle of construction of a synchro

α cos10 sdotsdot= UKU y

)120-( cos10 degsdotsdot= αUKU z

)240-( cos10 degsdotsdot= αUKU x

)120-( sin3100 degsdotsdotsdot=minus= αKUUUU yxyx

)240-( sin3100 degsdotsdotsdot=minus= αKUUUU zyzy

α sin3100 sdotsdotsdot=minus= KUUUU xzxz

Application to the Torque Sensor

Principle of construction of a torque-type synchro

Torque versus angular

difference

)( sin~ rt αα minussdotKM

)( cos~ rt1r αα minussdotUU

Principle of construction of a control-type sensor

Output voltage versus

angular difference

Principle of construction of a differential sychro

Eddy Current Sensors

tBE dd curl minus=JH = curl

0 div =BH(H)B sdot= micro

E(E)J sdot= σ

A B curl= A B curl=

tdd- A E =

)dd( tAJ minus= σ

tdd curl curl AA σmicro minus=

AA) σωmicro iminus= curl )(curl(1

AA) σωmicro i=∆)((1

Eddy Current Tachometer

Construction of a speedometer (courtesy VDO Adolf Schinding AG) 1) spindle 2) bearing

3) holding spring 4) iron yoke 5) eddy current cup 6) shaft of the magnet 7) support of

the magnet 8) temperature compensation 9) permanent magnet 10) torsion spring

Proximity Sensors

Schematic diagram of a proximity sensor

Output current of a proximity switch versus distance

Inductive Flowmeters

)( Btimessdot= υqF

EqF sdot=BE times=υ

)(ds Btimes== υEU )(ds Btimes== υEU

)( Bd timessdot= υU

Bsdotsdotsdot= υdKU

Development of magnetic phase detection

sensor for steam generator tube

Dirac Son1 Kwan-Sang Ryu2 Duck-Gun Park3

1Hannam University Daejeon Rep of Korea2Korea Research Institute of Standards and Science Daejeon Rep of Korea3KoreaAtomic Energy Research Institute Daejeon Rep of Korea

Introduction

The layout of pressurized water reactor (PWR) components

Primary side Secondary side (non-radioactive side)(radioactive side)

The Structure of SG(Steam Generator)(degradation mechanism)

Secondary SidePrimary Side

SCC

A B

A-B

Steam outlet

Anti-vibration

SCC

Fretting

Wall thinning

IGA

U-bend

In commercial power plants SG- height up to 21 m - weight up to 800 tons - 2~4 sets of SG were installed - SG can contain from 3000 to

16000 tubes each about 20 mmin diameter

Primary coolant outlet Primary coolant inlet

Anti-vibrationbars

Tubesupportplate

Tubesheet

IGA

SCC

Pitting

SCC

Inside Tubesheet

Top of Tubesheet

by SSHwang of KAERI

Denting

Sludge pile

in diameter

The SGT is made of nickel basedInconel alloy which is composed of 75 Ni 165Cr and 815Fe

-Degradation mechanism corrosion pitting denting inter granular attack

-Inspection Eddy current Testing(ECT)

Permeability Variation Clusters (PVC)

(Ferro-magnetic phase)

-005

000

005

010

015

m (emug)

1-1

-002

000

002

004

006

008

m (emug)

1-2

-1000 -500 0 500 1000

-015

-010

-005

H ( Am )

-1000 -500 0 500 1000

-006

-004

-002

H ( Am )

The hystresis loop in the fragment of PVC parts of Kori-1 retired SG tube

-004

-002

000

002

004

006

M (emug)

Inconel 600 tested at RT

under tensile stress

1 2 3

4 5 6

7 8 9-004

-002

000

002

004

006

M(emug)

Inconel 600 Heat treated at

602 oC under tensile stress

1 2 3

How can we detect magnetic phase

(PVC)selectively from the flaws in SGT

-3000 -2000 -1000 0 1000 2000 3000

-006

H (Oe)

7 8 9

10 11 12

-3000 -2000 -1000 0 1000 2000 3000

-006

-004

H(Oe)

4 5 6

7 8 9

The hysteresis loop of the tensile tested specimen at room temperature (a) and tensile tested at high temperature (b)

The magnetic phase can be created under the high temperature andpressure conditions which is correspond to the stress corrosion crackingin the SG tube in the NPP(Bruemmer SM Charlot LA amp Henager CH (1988) Corrosion 782)

Principle of ECT

If we can separate magnetic phase selectively from the

flaws using magnetic sensor the reliability of EC in SGT

inspection will be greatly enhanced

Structure of the permeability

sensor

Dimension and photograph of U-shape

sensing yoke

Design of Magnetic Sensor for PVC

sensor sensing yoke

Photograph of the completed sensor front side (above) and rear side (bottom)

R11R12

R10

R8

R6

R9

R13

R7

R14

C18

1 n

C17

C20

C21

D2

DIODE

SIN COS

-

+

U-2A

4

13

2

-

+

U-2B

75

6

8

-

+

U-3A

13

2

8

+5VC19

104

+5V

Schematic diagram of the sensor system

Electronic Circuit of Magnetic Sensor

R20

R

R21

R

-

+

U5AD797

3

26

74

U6

D1

S12

GND3

+VCC4VCC5

IN6

-VCC7

S28

C41

R13

R26

R18

R25

R2210 Ω

R16

R14

R17

10 k

R15

R27

R32

R28

R33

R29

R34

5 k

R30

C29

C37

104

C32473

C39473C40

104

C33

104

C21

104C23

104

C25

104

C26

104

C30

104

C31

104

C35

104

C36

104

C27

104

C28

104

C34

104

C38

104

D3

DIODE

L1

1

2

L2

1

2

L3

1

2

4

-

+

U-4A

4

13

2

-

+

U-4B

75

6

8

-

+

U-5A

4

13

2

-

+

U-5B

75

6

8

-

+

U-6A

4

13

2

-

+

U-6B

75

6

8

C22

104

-5V

+5V

+5V

+5V

+5V

+5V

+5V

U7

D1

S12

GND3

+VCC4

VCC5

IN6

-VCC7

S28

+5V

-5V

-5V

-5V

-5V

-5V

-5V

-5V

-5V

R19

R24

R

R23

R

C24

OUT(X)

OUT(Y)

R1

20 kR210 k

R3

20 kR410 k

C1

104

C8

104

REF43

OUT(X)

OUT(Y)

REF43

U2

+Vcc1

CH02

CH13

CH24

CH35

COMM6

SHDN7

Vref8

+Vcc9

GND10

GND11

DOUT12BUSY13DIN14CS15

DIN16

-

+

U-1A

13

2

8

-

+

U-1B

4

75

6

C410 uF

C5104

DOUT

C210uF

C6104

C3104

DCLK

C7104

DIN

C10

01uF

CS

BUSY

C14 10uF

J1

CON6

123456

D1

DIODE

R5

47K

C9

10uF

C1310uF

Y1

OSC

OUT3

GND2

VCC4

U3

RSTVPP1

GND10

VCC20

XTAL15

XTAL24

P10AIN012P11AIN113P1214P1315P1416P1517P1618P1719

P30RXD2

P31TXD3

P32INT06

P33INT17

P34T08

P35T19

P3711

U4

C1+1

C1-3

C2+4

C2-5

VCC16

GND15

V+2

V-6

R1OUT12

R2OUT9

T1IN11

T2IN10

R1IN13

R2IN8

T1OUT14

T2OUT7

C12 10uF

C16

01uF

C15 10uF

C11

01uF

-5V

+5V

+5V

+5V

+5V

+5V

+5V

+5V

RST

OSC

OSC

RST

DCLKCSDINBUSYDOUT

U1

IN2

GND

4

OUT6

TEMP3

TRIM5

-5V

+5V

Electronic circuit diagram of the magnetic sensor

Photograph of the completed measuring system data acquisition

software in PC and probe scanning system

Experimental Setup for Magnetic Sensor

Reference material Scanning System Software LabVIEW

Reference Material (1) Normal defects and PVCs

Longitudinal and transverse defects

Def W L D Remarks

1 02 500 0213 (20 ) Inner defects

2 02 500 0427 (40 )

3 02 500 0213 (20 )Outer defectsPVC(1018)4 02 500 0427 (40 )

5 02 500 0639 (60 )

6 02 500 0852 (80 )

7 02 500 0639 (60 ) Inner defects

8 02 500 0852 (80 )

- 1 and 2 are inner defects

- 345 and 6 are outer defects with PVC

- 7 and 8 are inner defects

PVC

PVC

Defect Defect

For longitudinal defects and PVC For circumferential defects and PVC

ECT is very difficult to detect circumferential defects

We can distinguish PVCs and defects and longitudinal and circumferential defects

Flux-gate Magnetometer

One core sensor Two core sensor

3-축 flux-gate Magnetometer의 계략도

Sensorpia Co

pro

cess

or(

AV

R)

Sensor 1

RS422

Interface

Mic

ro-p

roce

ssor(

AV

R)

Sensor 2

Sensor 3

Interface

조립된 마그네토미터의 사진

Sensorpia Co

Analog PCB

Digital PCB

Sensorpia Co선형도(linearity)

10

20

30

40

50

60

y-axis

Magnetometer Output (microT)

-60 -50 -40 -30 -20 -10 0 10 20 30 40 50 60

-60

-50

-40

-30

-20

-10

0

10

Y-axis y=099946 x+0015STD 106E-4

Magnetometer Output (

Applied Magnetic Field (microT)

마그네토미터의 noise 특성 Sensorpia Co

1

10

100

y-axis

Magnetometer noise (nT)

0 1 2 3 4 5 6

1E-4

1E-3

001

01

Magnetometer noise (nT)

Frequency (Hz)

Magnetometer for KoDSAT

-150 -100 -50 0 50 100 150

-15

-10

-5

0

5

10

15

Magnetic Moment (Am

2)

Current (mA)

After Thermal Cycle Test

Measured

Resistance 193 ohm

Photograph of Magnetic torquer

Photograph of KoDSAT

Photograph of

3-axis Fluxgate

Magnetometer

Photograph of Magnetic torquer

Application of magnetometer

Moon magnetic fieldmeasurement

Telescope with direction indication

Joule Effect (Magnetostriction)

ϕ2cosel

l=

∆

0=∆

+∆

+∆

b

b

a

a

l

l

Actuator using Terfenol-D

00

05

10

B (T)

800

1000

1200

1400

1600

Magnetostriction (ppm)

-100 -50 0 50 100

-10

-05

00

B (T)

H (kAm)

2 MPa

4 MPa

6 MPa

8 MPa

10 MPa

12 MPa

-100 -50 0 50 100

-200

0

200

400

600

Magnetostriction (ppm)

H (kAm)

2 MPa

4 MPa

6 MPa

8 MPa

10 MPa

12 MPa

600

700

800

900

1000

-4 -3 -2 -1 0 1 2 3 4

0

10

20

30

40

50

60

Displacement (m

icro meter)

I (A)

FIELD

9 kAm

12 kAm

16 kAm

20 kAm

24 kAm

38 kAm

-50 -40 -30 -20 -10 0 10 20 30 40 50

-100

0

100

200

300

400

500

L (PPM)

H (kAm)

9 kAm

12 kAm

16 kAm

20 kAm

24 kAm

38 kAm

Magnetostrictive displacement sensor

Hysteresis loops under

tensile stress σ

(a) Crystalline 68 NiFe

λs = +25 10-6

(b) crystalline pure Ni λs

= -35 10-6

Villari Effect ( Inverse of Joule Effect)

= -35 10-6

(c) amorphous Co-based

alloy

λs = -35 10-6

ϕσλ 2sin2

3sdotsdot= smeE

γ

Permeability depending on the stress

σλmicromicro

1

3

2

Y

J

so

s

r =

γ

Calculated magnetization curves under stress

Variation of magnetization curve by an applied

tensile force (Co-based amorphous alloy)

Alloy Requirement

Materials for magnetoelastic sensors

Why amorphous magnetic materials are important

Stress-strain curves of several materials

Coercivity and hardness of several materials

Principles of magnetoelastic sensors

Non-contact torque sensor

Principle of cross torductor torque

sensor and flux pattern of sensor

poles on the surface of a shaft

a) without and b)with torsional load

Equivalent magnetic circuit of

cross type torque sensor

Helices of principal tensile and compressive stress on the surface of

a shaft subjected to torsion [32] Correlated changes of permeability

are detected by four-branch yoke system with sensing coils 123

and 4 and a common excitation pole

Examples of torque sensors

Four-branch type torque sensor

heads Pole structures realized

by commercial multi-pole

ferrites 14 and 18 min in

diameter (diameter of sensor

h e a d 1 7 a n d 2 4 m m

respectively) respectively)

Principle of Ring Torductor torque transducer

(a b) Physical structure (c) evolution of the

shaft surface under the transducer poles A and BRing torductor for measuring

torque on ship propeller shafts

(shaft diameter ca 500 mm)

(Courtesy ASEA Brown

Boveri AG)

Principal designs of coaxial torque sensors

Schematic diagram of data processing

electronics of a torque sensor

Extensometer (a) Construction of strain sensing element using

amorphous ribbon wound core (b) configuration of lumped

windings

∆E effect of an amorphous FeNi-based

alloy (Fe40 Ni38 Mo4 B18) Hs saturation

field

Magnetically tunable delay line

Torque Sensors using Amorphous wire

Sixtus tonk효과(large Barkhausen효과)

Hysteresis loops of a Wiegand wire for different reset fields

Curie 온도 및Hopkinson효과

Relation between normalised

saturation polarisation and

normalised Curie temperature

Permeability of a Mn-Zn ferrite as

a function of temperature and field

strength

Conclusions

1) Magnetic sensor 는 자동차 공장자동화 항공우주 및 군사용으로많이 사용되고 있다

2) 새로운 소재개발은 자기센서의 성능개발에 직접적인 영향을 준다2) 새로운 소재개발은 자기센서의 성능개발에 직접적인 영향을 준다

3) 센서의 개발을 위해서는 다양한 전공지식이 요구된다

(물리학 재료공학 기계공학 전자공학)

4) 센서분야가 고부가가치를 창출하는 부품사업이다

5) 핵심부품을 생산하는 중소기업의 item으로도 적절하다

Sensor in Automobiles

Definition of Magnetic Sensor

Sensors which are associated with the laws and effects of magnetic and electromagnetic fields

Why are Magnetic Sensors ImportantWhy are Magnetic Sensors Important

1) High reliability Military Flux-gate Search coil

Automobile ABS non-contact angle

Air and space Magnetic torquer Flux-gate

2) High Temperature LVDT Flux-gate

3) High radiation Eddy current probe and LVDT used in nuclear

power plant

Magnetic Effects for SensorsYear Effect Explanation Technical Use

1842 Joule effect Change in shape of a ferromagnetic body with magnetization (magnetostriction)

In combination with piezoelectric elements for magnetometers and potentiometers

1846 ΔE effect Chang in Youngrsquos modulus with magnetization Acoustic delay line components for magnetic field measurement

1847 Matteucci effect Torsion of a ferromagnetic rod in a longitudinal field changes magnetization

Magnetoelastic sensor

1856 Magnetoresistance

(AMR)

Change in resistance with magnetic field Magnetoresistive sensors

1858 Wiedemann effect A torsion is produced in a current carrying ferromagnetic rod when subjected to a longitudinal field

Torque and force measurement

1865 Villari effect Effect on magnetization by tensile or compressive strength

Magnetoelastic sensorsstrength

1879 Hall effect A current carrying crystal produces a transverse voltage when subjected to a magnetic field vertical to its surface

Magnetogalvanic sensors

1903 Skin effect Displacement of current from the interior of material to surface layer due to eddy currents

Distance sensors proximity sensors

1931 Sixtus Tonks effect Pulse magnetization by large Barkhausen jumps Wiegand and pulse-wire sensors

1962 Josephson effect Tunnel effect between two superconducting materials with an extremely thin separating layer quantum effect

SQUID magnetometers

1987 GMR effect Quantum mechanical magnetoresistance effect observed in thin-film structures composed of alternating ferromagnetic and non-magnetic conductive layers

Magnetic field sensor

Sprintonics

1994 GMI effect Large variations that the electrical impedance of some materials exhibits as a function of an external magnetic field

Magnetic field sensor

Principle of search coil type magnetometerPrinciple of search coil type magnetometer

int intint sdotminus=sdotA

ABt

sE d d

dd

Faradayrsquos Induction Law

Faraday 전자기유도법칙

Atd

HAnnU sdotsdotsdotsdot=Φsdotsdot= microωω max0

Voltage output from magnetometer

Sensitivity and Noise of Air Cored Induction Coil

HfDnHAnnU sdotsdotsdotsdotsdot=sdotsdotsdotsdot=Φsdotsdot= 02

2

0max02

microπ

microωω

2

022

00

microπ sdotsdot=

sdot=

Dn

Hf

US

V2π

sdotsdot=

sdotsdot

sdot= minus2

-970

m Hz nT

V10

m A

S V104πmicro

sdot

sdotsdot= minus

Hz nT

V10

2

922

0 DnUπ

Air-cored induction coil in a time-varying magnetic field

sdot

sdotsdot= minus

Hz nT

V10

2

922

0 DnUπ

Air-cored coil output voltage U0 at a magnetic field x frequency product

1 nT middot Hz versus diameter D with number of turns n as parameter

4

22 dDnWW

sdotsdotsdotsdot=

γπ Weight of coil

Coil resistance2

4

d

nDRDC

ρ=

Thermal voltage noisefTRU DCBN ∆= κ4

W

4W

DnfTU BN

sdotsdotsdotsdot∆=

πγρκ

fHnDdTk

DfHW

TkU

UNS

BBN

sdotsdotsdot

=sdotsdotsdot

== 21302

w00 )(28242

σmicroπ

γρmicroπ

Noise voltage

1028

ln286 9minussdot

+minus= αd

DDL

Equivalent circuit diagram of an air-cored induction coil

For single turn loop Dgtgtd

Long single layer solenoid

[H] 10 H][ 10 922

9222

minusminus sdotsdotsdot

=sdotsdotsdot

asympwd

nD

w

nDL

ππ

622

10 101 46

minussdot+sdot

asympwD

nDL

922

10 10 9 3

778 minussdot++sdot

asymphwD

nDL

Short single layer solenoid wgt16D

Multi-layer solenoid Dgtgtwh

( ) 1

370

ndc

DwC r

sdotminussdotsdotsdot

=ε

1

i

2tot minus+=k

C

k

CC

Capacitance C of a coil

Capacitance C of a single-layer coil normalized to

its diameter D versus length-to-diameter ratio wD

of the coil (capacitance C in pF and geometrical

dimensions w and D in cm)

12 minuskk

High permeability core induction coil

Magnetic field pattern around high permeability core

when it is inserted into a homogeneous field It is valid

for low frequencies and if the coil indicated at the middle

of the core is without current

Magnetization of a high permeability core

dt

dnu ci

i Φ

sdotminus= ) ( cosmaxc ci tωsdotΦ=Φ

ci0rc0 maxAHnnU sdotsdotsdotsdot=Φsdotsdot= micromicroωω

HNHHHH )1( minusminus=+= micro

HN

H sdotminus+

=)1(1

1

r

i micro

irdmi HNHHHH )1( minusminus=+= micro

HfAnU sdotsdotsdotsdotsdotsdot= 0cc0 2 micromicroπ

)1(1 r

rc minus+=

micromicro

microN

minus++

minusminus=

infin1)1ln(

11

1 2

22ell mmm

m

mN

10326) (1ln 152

10156) (1ln 262

ell

cyl

++++

=infin

infin

N

N

Induction coil on a cylindrical high permeability core

Demagnetization factorDemagnetization factorN of prolate ellipsoidsand cylindrical rods(descending curves) andcore permeability μc

(ascending curves) ofcylindrical rods versusthe length-to-diameterratio m of the rod withmaterial permeability μr

as parameter

Core permeability μc of cylindrical rods versus thematerial permeability μr with length-to-diameter ratiom of the rod as parameter after

Minimum noise equivalent magnetic field spectral density of an induction coil sensor with high permeability core versus sensor weight Ws (at length-to-diameter ratios m = 50 and 100 permeability μr = 10000 of the core material and f = 1 Hz)

Induction coil sensors with electronic amplifier

II

rKLC

1=ω

II

II

RR

RK

+=

rr

2 i 1

)(

ωω

ωω

ω

D

KF

+

minus

=

+=

II

II

II

2

C

L

R

R

C

L

KD

Frequency responses of the search coil

Frequency responses of thesensitivity SA and the output voltage UA

of an induction coil sensor with a voltageamplifier at a constant magnetic fieldamplitude

Resonance step-up of thesensitivity SA at differentvalues of the damping D

Sensor with transformer coupled negative feedback to the coil

)(i)()(F

0 ωωωω FR

UMUAU A

A sdot

minus=

)( i1

)(

F

0

ωω

ω

FR

MA

FAUU A

sdot+

sdot=

Induction coil connected to a voltage amplifier with

transformer coupled negative feedback to the coil

FR

21

1K0

i1

1

i1

i )(

ωωωωωω

ωω

+sdot

+sdot=

M

RUU A

IIF2 CRL

MAf

sdotsdotsdotsdot

=∆π

Frequency response of the output voltage UA of an induction coil sensor with negative feedback transformer coupled to the coil

Applications of search coil magnetometer

Developed search coil magnetometer using amorphous ribbon

Experimental setup for the effective permeability measurement

Relative permeability depending on the numbers of ribbon(a)

and the air gap between ribbons

Relative permeability depending on the number of ribbons for the different air gap between ribbons

Relative permeability depending on the total number of ribbons for the different air gap between ribbons

10 pT

100 pT

1 pT

Noise spectrum of the developed search coil magnetometer

BJne

E xH

1minus=

neRH

1minus=

22 nP micromicro minus

Hall 효과

Bt

IRU H

HL =

2

22

)( he

eh

Hpne

nPR

micromicromicromicro

+

minus=

Rectangular Hall plate (cc1cc2 current constant sc1sc2

sensor constant I bias current U voltage drop UH Hall

voltage

Physics carrier concentration and kind of carrier measurement

Engineering magnetic field measurement

Current Measurement

Arrangement for noninvasive

current measurement using an iron

core The current to be measured

produces a proportional magnetic

field which can be measured in the

air gap

Characteristic curve produced by

the current

Arrangement for indirect noninvasive

current measurement using the

compensation principle An iron core as

represented in Figure 3-29 is held field

free by injection a current into a

compensating coil wound on the core

which offsets the field generated by the

current being measured The Hall effect

sensor in the air gap serves as a null

indicator

Circuit diagram for AC-power

measurement using a Hall effect

sensor

DC Power Measurement

Circuit diagram for DC-

power measurement using a

Hall effect sensor

Noncontact Position Sensing

Galvanomagnetic components for sensing the position of permanent magnets

and magnetically conductive materials

Current Sensor Based on Hall Sensor

and Magnetic Core for Hybrid Vehicle

KH Yeon1 SD Kim1 and D Son2 1Auto industry co14F Hanshin IT tower Guro Gu Seoul Korea2Hannam UniversityOjung dong 133 Daejeon Rep of Korea

i

Hall sensor

B

I

SB

ring core

B

I10

g

N

Bl S

micro

)( gtgtrmicro

gab core

Current Sensor Based on Hall

Sensor and Magnetic Core

Hall

Effect

Device

CurrentVoltage

applying for

Hall effect device

operation

Output

signals

Magnetic field

Occurred by

current measurement

Signal

process

circuits

Developed Current Sensor

Magnetic core

Hall sensor

PCB

25

30

35

40

45

50

Output voltage V

Current sensor(Open loop type)

Temp 25C

400A model

+400 ~ -400A

SD 000128

Linearity 003

Linearity of the sensor

Characteristics of the Current Sensors

1000A 10 V power supply

-500 -400 -300 -200 -100 0 100 200 300 400 500

00

05

10

15

20

Output voltage V

current A

Temperature 25Linearity 003

Measuring range -400A ~ +400A

1000A Electronic Load

-3

0

3

6

9

12

15

18

dB

Current sensor

DV2 PCB 24pF

40Aturns

Frequency bandwidth

Gain bandwidth 3 MHz

Current 10 A

Temperature 25

Frequency bandwidth 100 kHz

Sensor output voltage vs frequency

at applied current of 40 Aturns

1 10 100

-18

-15

-12

-9

-6

Frequency kHz 측정온도 25

주파수특성 30kHz 이상(3dB 기준)

측정전류 40Aturns(4A 10턴)

측정주파수 100Hz ~ 100kHz

Temperature 25Current 40Aturns

Frequency range 100 Hz ~ 100 kHz

What is Magnetoresistance

Magnetoresistance effect(AMR)

θθθ 2cos2

12sin12cos(

22 minusminus+∆asymp∆ xxxmx hhhRR

32 minusasymp∆ ρρ New effect GMR CMR and GMI

10 ge∆ ρρ

Two bridge configuration for

rotational angle measurement

measurement angle more than 180o

자동차 Engine Management System

Inductive and Eddy Current

Sensors Excited by Permanent Magnets

tNtU dd)( φsdotminus=

construction of an inductive

sensor (courtesy VDO Adolf sensor (courtesy VDO Adolf

Schindling AG)

1) constant socket

2) terminal package

3) permanent magnet

4) cap

5) soft magnetic core

6) coil

7) plate

8) blade connector

γγ

Sensor with yoke Change in the magnetic flux with

varying air gap Continuous lines

minimum air gap dashed lines

maximum air gap

C-shaped sensor

Sensor with radially

magnetized

permanent magnet

Signal Conditioning

Output voltage U of a DC-excited sensor with permanent

magnets when a single iron object passes by

Schematic electrical diagram of an inductive sensor

Linear Variable Differential Transformer

AC-Excited Sensors for Linear Movement

Principle of construction of an LVDT

Electrical circuit of an LVDT

tIMtNU dd dd sdotminus=sdotminus= φ

tIMtIMUUU dd dd 1212 sdotminussdot=minus=

tIMMU dd)( 12 sdotminus=

)(12 xMMMM =minus=

tIxMU dd)( sdot= tI

UxM

dd)( =

Signal Conditioning

power supply

carrier gen

autoampcontrol

LVDTcarrieramp

demod-ulator

phase

shifter

power supply

carrier gen

passivedemod-ulator

LVDTDCamp

Block diagram of a carrier amplifier system

Block diagram of a DC amplifier system

Variable Inductive Sensors

Principle of construction

of the VLP sensor

Principle of a bridge

circuit

lANL r 20 sdotsdotsdot= micromicro

21 BA UUU minus=

21)i(ii( 211 minus+sdot= LLLUU BA ωωω

)21))()((( minus∆minus+∆+∆+sdot= LLLLLLUU BA

)212)(( minus∆+sdot= LLLUU )212)(( minus∆+sdot= LLLUU BA

LLUU BA 21 ∆sdotsdot=

llLL ∆sdot=∆ d d

llLLUU BA ∆sdotsdot= d d)2(1

Applications and Properties

Principle of a construction of a force transducer

(courtesy Hottinger Baldwin Messtechnik)

Vibrationacceleration sensor

Signal Conditioning

Schematic electrical diagram of a force transducer connected with an

amplifier (courtesy Hottinger Baldwin Messtechnik GmbH)

Variable Gap Sensors

)( FeFe2

0 LLllANL micromicromicro +sdotsdot=

FeFe2

0max lANL sdotsdotsdot= micromicro

Construction of a variable gap sensor

Characteristic of a variable gap sensor

Construction of a differential

cross-anchor sensor

Output voltage U versus core

position x plusmn a limits of the

linear rage

Applications of differential cross-anchor sensors

AC-excited Sensors for Rotary Movements

Principle of construction of a synchro

α cos10 sdotsdot= UKU y

)120-( cos10 degsdotsdot= αUKU z

)240-( cos10 degsdotsdot= αUKU x

)120-( sin3100 degsdotsdotsdot=minus= αKUUUU yxyx

)240-( sin3100 degsdotsdotsdot=minus= αKUUUU zyzy

α sin3100 sdotsdotsdot=minus= KUUUU xzxz

Application to the Torque Sensor

Principle of construction of a torque-type synchro

Torque versus angular

difference

)( sin~ rt αα minussdotKM

)( cos~ rt1r αα minussdotUU

Principle of construction of a control-type sensor

Output voltage versus

angular difference

Principle of construction of a differential sychro

Eddy Current Sensors

tBE dd curl minus=JH = curl

0 div =BH(H)B sdot= micro

E(E)J sdot= σ

A B curl= A B curl=

tdd- A E =

)dd( tAJ minus= σ

tdd curl curl AA σmicro minus=

AA) σωmicro iminus= curl )(curl(1

AA) σωmicro i=∆)((1

Eddy Current Tachometer

Construction of a speedometer (courtesy VDO Adolf Schinding AG) 1) spindle 2) bearing

3) holding spring 4) iron yoke 5) eddy current cup 6) shaft of the magnet 7) support of

the magnet 8) temperature compensation 9) permanent magnet 10) torsion spring

Proximity Sensors

Schematic diagram of a proximity sensor

Output current of a proximity switch versus distance

Inductive Flowmeters

)( Btimessdot= υqF

EqF sdot=BE times=υ

)(ds Btimes== υEU )(ds Btimes== υEU

)( Bd timessdot= υU

Bsdotsdotsdot= υdKU

Development of magnetic phase detection

sensor for steam generator tube

Dirac Son1 Kwan-Sang Ryu2 Duck-Gun Park3

1Hannam University Daejeon Rep of Korea2Korea Research Institute of Standards and Science Daejeon Rep of Korea3KoreaAtomic Energy Research Institute Daejeon Rep of Korea

Introduction

The layout of pressurized water reactor (PWR) components

Primary side Secondary side (non-radioactive side)(radioactive side)

The Structure of SG(Steam Generator)(degradation mechanism)

Secondary SidePrimary Side

SCC

A B

A-B

Steam outlet

Anti-vibration

SCC

Fretting

Wall thinning

IGA

U-bend

In commercial power plants SG- height up to 21 m - weight up to 800 tons - 2~4 sets of SG were installed - SG can contain from 3000 to

16000 tubes each about 20 mmin diameter

Primary coolant outlet Primary coolant inlet

Anti-vibrationbars

Tubesupportplate

Tubesheet

IGA

SCC

Pitting

SCC

Inside Tubesheet

Top of Tubesheet

by SSHwang of KAERI

Denting

Sludge pile

in diameter

The SGT is made of nickel basedInconel alloy which is composed of 75 Ni 165Cr and 815Fe

-Degradation mechanism corrosion pitting denting inter granular attack

-Inspection Eddy current Testing(ECT)

Permeability Variation Clusters (PVC)

(Ferro-magnetic phase)

-005

000

005

010

015

m (emug)

1-1

-002

000

002

004

006

008

m (emug)

1-2

-1000 -500 0 500 1000

-015

-010

-005

H ( Am )

-1000 -500 0 500 1000

-006

-004

-002

H ( Am )

The hystresis loop in the fragment of PVC parts of Kori-1 retired SG tube

-004

-002

000

002

004

006

M (emug)

Inconel 600 tested at RT

under tensile stress

1 2 3

4 5 6

7 8 9-004

-002

000

002

004

006

M(emug)

Inconel 600 Heat treated at

602 oC under tensile stress

1 2 3

How can we detect magnetic phase

(PVC)selectively from the flaws in SGT

-3000 -2000 -1000 0 1000 2000 3000

-006

H (Oe)

7 8 9

10 11 12

-3000 -2000 -1000 0 1000 2000 3000

-006

-004

H(Oe)

4 5 6

7 8 9

The hysteresis loop of the tensile tested specimen at room temperature (a) and tensile tested at high temperature (b)

The magnetic phase can be created under the high temperature andpressure conditions which is correspond to the stress corrosion crackingin the SG tube in the NPP(Bruemmer SM Charlot LA amp Henager CH (1988) Corrosion 782)

Principle of ECT

If we can separate magnetic phase selectively from the

flaws using magnetic sensor the reliability of EC in SGT

inspection will be greatly enhanced

Structure of the permeability

sensor

Dimension and photograph of U-shape

sensing yoke

Design of Magnetic Sensor for PVC

sensor sensing yoke

Photograph of the completed sensor front side (above) and rear side (bottom)

R11R12

R10

R8

R6

R9

R13

R7

R14

C18

1 n

C17

C20

C21

D2

DIODE

SIN COS

-

+

U-2A

4

13

2

-

+

U-2B

75

6

8

-

+

U-3A

13

2

8

+5VC19

104

+5V

Schematic diagram of the sensor system

Electronic Circuit of Magnetic Sensor

R20

R

R21

R

-

+

U5AD797

3

26

74

U6

D1

S12

GND3

+VCC4VCC5

IN6

-VCC7

S28

C41

R13

R26

R18

R25

R2210 Ω

R16

R14

R17

10 k

R15

R27

R32

R28

R33

R29

R34

5 k

R30

C29

C37

104

C32473

C39473C40

104

C33

104

C21

104C23

104

C25

104

C26

104

C30

104

C31

104

C35

104

C36

104

C27

104

C28

104

C34

104

C38

104

D3

DIODE

L1

1

2

L2

1

2

L3

1

2

4

-

+

U-4A

4

13

2

-

+

U-4B

75

6

8

-

+

U-5A

4

13

2

-

+

U-5B

75

6

8

-

+

U-6A

4

13

2

-

+

U-6B

75

6

8

C22

104

-5V

+5V

+5V

+5V

+5V

+5V

+5V

U7

D1

S12

GND3

+VCC4

VCC5

IN6

-VCC7

S28

+5V

-5V

-5V

-5V

-5V

-5V

-5V

-5V

-5V

R19

R24

R

R23

R

C24

OUT(X)

OUT(Y)

R1

20 kR210 k

R3

20 kR410 k

C1

104

C8

104

REF43

OUT(X)

OUT(Y)

REF43

U2

+Vcc1

CH02

CH13

CH24

CH35

COMM6

SHDN7

Vref8

+Vcc9

GND10

GND11

DOUT12BUSY13DIN14CS15

DIN16

-

+

U-1A

13

2

8

-

+

U-1B

4

75

6

C410 uF

C5104

DOUT

C210uF

C6104

C3104

DCLK

C7104

DIN

C10

01uF

CS

BUSY

C14 10uF

J1

CON6

123456

D1

DIODE

R5

47K

C9

10uF

C1310uF

Y1

OSC

OUT3

GND2

VCC4

U3

RSTVPP1

GND10

VCC20

XTAL15

XTAL24

P10AIN012P11AIN113P1214P1315P1416P1517P1618P1719

P30RXD2

P31TXD3

P32INT06

P33INT17

P34T08

P35T19

P3711

U4

C1+1

C1-3

C2+4

C2-5

VCC16

GND15

V+2

V-6

R1OUT12

R2OUT9

T1IN11

T2IN10

R1IN13

R2IN8

T1OUT14

T2OUT7

C12 10uF

C16

01uF

C15 10uF

C11

01uF

-5V

+5V

+5V

+5V

+5V

+5V

+5V

+5V

RST

OSC

OSC

RST

DCLKCSDINBUSYDOUT

U1

IN2

GND

4

OUT6

TEMP3

TRIM5

-5V

+5V

Electronic circuit diagram of the magnetic sensor

Photograph of the completed measuring system data acquisition

software in PC and probe scanning system

Experimental Setup for Magnetic Sensor

Reference material Scanning System Software LabVIEW

Reference Material (1) Normal defects and PVCs

Longitudinal and transverse defects

Def W L D Remarks

1 02 500 0213 (20 ) Inner defects

2 02 500 0427 (40 )

3 02 500 0213 (20 )Outer defectsPVC(1018)4 02 500 0427 (40 )

5 02 500 0639 (60 )

6 02 500 0852 (80 )

7 02 500 0639 (60 ) Inner defects

8 02 500 0852 (80 )

- 1 and 2 are inner defects

- 345 and 6 are outer defects with PVC

- 7 and 8 are inner defects

PVC

PVC

Defect Defect

For longitudinal defects and PVC For circumferential defects and PVC

ECT is very difficult to detect circumferential defects

We can distinguish PVCs and defects and longitudinal and circumferential defects

Flux-gate Magnetometer

One core sensor Two core sensor

3-축 flux-gate Magnetometer의 계략도

Sensorpia Co

pro

cess

or(

AV

R)

Sensor 1

RS422

Interface

Mic

ro-p

roce

ssor(

AV

R)

Sensor 2

Sensor 3

Interface

조립된 마그네토미터의 사진

Sensorpia Co

Analog PCB

Digital PCB

Sensorpia Co선형도(linearity)

10

20

30

40

50

60

y-axis

Magnetometer Output (microT)

-60 -50 -40 -30 -20 -10 0 10 20 30 40 50 60

-60

-50

-40

-30

-20

-10

0

10

Y-axis y=099946 x+0015STD 106E-4

Magnetometer Output (

Applied Magnetic Field (microT)

마그네토미터의 noise 특성 Sensorpia Co

1

10

100

y-axis

Magnetometer noise (nT)

0 1 2 3 4 5 6

1E-4

1E-3

001

01

Magnetometer noise (nT)

Frequency (Hz)

Magnetometer for KoDSAT

-150 -100 -50 0 50 100 150

-15

-10

-5

0

5

10

15

Magnetic Moment (Am

2)

Current (mA)

After Thermal Cycle Test

Measured

Resistance 193 ohm

Photograph of Magnetic torquer

Photograph of KoDSAT

Photograph of

3-axis Fluxgate

Magnetometer

Photograph of Magnetic torquer

Application of magnetometer

Moon magnetic fieldmeasurement

Telescope with direction indication

Joule Effect (Magnetostriction)

ϕ2cosel

l=

∆

0=∆

+∆

+∆

b

b

a

a

l

l

Actuator using Terfenol-D

00

05

10

B (T)

800

1000

1200

1400

1600

Magnetostriction (ppm)

-100 -50 0 50 100

-10

-05

00

B (T)

H (kAm)

2 MPa

4 MPa

6 MPa

8 MPa

10 MPa

12 MPa

-100 -50 0 50 100

-200

0

200

400

600

Magnetostriction (ppm)

H (kAm)

2 MPa

4 MPa

6 MPa

8 MPa

10 MPa

12 MPa

600

700

800

900

1000

-4 -3 -2 -1 0 1 2 3 4

0

10

20

30

40

50

60

Displacement (m

icro meter)

I (A)

FIELD

9 kAm

12 kAm

16 kAm

20 kAm

24 kAm

38 kAm

-50 -40 -30 -20 -10 0 10 20 30 40 50

-100

0

100

200

300

400

500

L (PPM)

H (kAm)

9 kAm

12 kAm

16 kAm

20 kAm

24 kAm

38 kAm

Magnetostrictive displacement sensor

Hysteresis loops under

tensile stress σ

(a) Crystalline 68 NiFe

λs = +25 10-6

(b) crystalline pure Ni λs

= -35 10-6

Villari Effect ( Inverse of Joule Effect)

= -35 10-6

(c) amorphous Co-based

alloy

λs = -35 10-6

ϕσλ 2sin2

3sdotsdot= smeE

γ

Permeability depending on the stress

σλmicromicro

1

3

2

Y

J

so

s

r =

γ

Calculated magnetization curves under stress

Variation of magnetization curve by an applied

tensile force (Co-based amorphous alloy)

Alloy Requirement

Materials for magnetoelastic sensors

Why amorphous magnetic materials are important

Stress-strain curves of several materials

Coercivity and hardness of several materials

Principles of magnetoelastic sensors

Non-contact torque sensor

Principle of cross torductor torque

sensor and flux pattern of sensor

poles on the surface of a shaft

a) without and b)with torsional load

Equivalent magnetic circuit of

cross type torque sensor

Helices of principal tensile and compressive stress on the surface of

a shaft subjected to torsion [32] Correlated changes of permeability

are detected by four-branch yoke system with sensing coils 123

and 4 and a common excitation pole

Examples of torque sensors

Four-branch type torque sensor

heads Pole structures realized

by commercial multi-pole

ferrites 14 and 18 min in

diameter (diameter of sensor

h e a d 1 7 a n d 2 4 m m

respectively) respectively)

Principle of Ring Torductor torque transducer

(a b) Physical structure (c) evolution of the

shaft surface under the transducer poles A and BRing torductor for measuring

torque on ship propeller shafts

(shaft diameter ca 500 mm)

(Courtesy ASEA Brown

Boveri AG)

Principal designs of coaxial torque sensors

Schematic diagram of data processing

electronics of a torque sensor

Extensometer (a) Construction of strain sensing element using

amorphous ribbon wound core (b) configuration of lumped

windings

∆E effect of an amorphous FeNi-based

alloy (Fe40 Ni38 Mo4 B18) Hs saturation

field

Magnetically tunable delay line

Torque Sensors using Amorphous wire

Sixtus tonk효과(large Barkhausen효과)

Hysteresis loops of a Wiegand wire for different reset fields

Curie 온도 및Hopkinson효과

Relation between normalised

saturation polarisation and

normalised Curie temperature

Permeability of a Mn-Zn ferrite as

a function of temperature and field

strength

Conclusions

1) Magnetic sensor 는 자동차 공장자동화 항공우주 및 군사용으로많이 사용되고 있다

2) 새로운 소재개발은 자기센서의 성능개발에 직접적인 영향을 준다2) 새로운 소재개발은 자기센서의 성능개발에 직접적인 영향을 준다

3) 센서의 개발을 위해서는 다양한 전공지식이 요구된다

(물리학 재료공학 기계공학 전자공학)

4) 센서분야가 고부가가치를 창출하는 부품사업이다

5) 핵심부품을 생산하는 중소기업의 item으로도 적절하다

Definition of Magnetic Sensor

Sensors which are associated with the laws and effects of magnetic and electromagnetic fields

Why are Magnetic Sensors ImportantWhy are Magnetic Sensors Important

1) High reliability Military Flux-gate Search coil

Automobile ABS non-contact angle

Air and space Magnetic torquer Flux-gate

2) High Temperature LVDT Flux-gate

3) High radiation Eddy current probe and LVDT used in nuclear

power plant

Magnetic Effects for SensorsYear Effect Explanation Technical Use

1842 Joule effect Change in shape of a ferromagnetic body with magnetization (magnetostriction)

In combination with piezoelectric elements for magnetometers and potentiometers

1846 ΔE effect Chang in Youngrsquos modulus with magnetization Acoustic delay line components for magnetic field measurement

1847 Matteucci effect Torsion of a ferromagnetic rod in a longitudinal field changes magnetization

Magnetoelastic sensor

1856 Magnetoresistance

(AMR)

Change in resistance with magnetic field Magnetoresistive sensors

1858 Wiedemann effect A torsion is produced in a current carrying ferromagnetic rod when subjected to a longitudinal field

Torque and force measurement

1865 Villari effect Effect on magnetization by tensile or compressive strength

Magnetoelastic sensorsstrength

1879 Hall effect A current carrying crystal produces a transverse voltage when subjected to a magnetic field vertical to its surface

Magnetogalvanic sensors

1903 Skin effect Displacement of current from the interior of material to surface layer due to eddy currents

Distance sensors proximity sensors

1931 Sixtus Tonks effect Pulse magnetization by large Barkhausen jumps Wiegand and pulse-wire sensors

1962 Josephson effect Tunnel effect between two superconducting materials with an extremely thin separating layer quantum effect

SQUID magnetometers

1987 GMR effect Quantum mechanical magnetoresistance effect observed in thin-film structures composed of alternating ferromagnetic and non-magnetic conductive layers

Magnetic field sensor

Sprintonics

1994 GMI effect Large variations that the electrical impedance of some materials exhibits as a function of an external magnetic field

Magnetic field sensor

Principle of search coil type magnetometerPrinciple of search coil type magnetometer

int intint sdotminus=sdotA

ABt

sE d d

dd

Faradayrsquos Induction Law

Faraday 전자기유도법칙

Atd

HAnnU sdotsdotsdotsdot=Φsdotsdot= microωω max0

Voltage output from magnetometer

Sensitivity and Noise of Air Cored Induction Coil

HfDnHAnnU sdotsdotsdotsdotsdot=sdotsdotsdotsdot=Φsdotsdot= 02

2

0max02

microπ

microωω

2

022

00

microπ sdotsdot=

sdot=

Dn

Hf

US

V2π

sdotsdot=

sdotsdot

sdot= minus2

-970

m Hz nT

V10

m A

S V104πmicro

sdot

sdotsdot= minus

Hz nT

V10

2

922

0 DnUπ

Air-cored induction coil in a time-varying magnetic field

sdot

sdotsdot= minus

Hz nT

V10

2

922

0 DnUπ

Air-cored coil output voltage U0 at a magnetic field x frequency product

1 nT middot Hz versus diameter D with number of turns n as parameter

4

22 dDnWW

sdotsdotsdotsdot=

γπ Weight of coil

Coil resistance2

4

d

nDRDC

ρ=

Thermal voltage noisefTRU DCBN ∆= κ4

W

4W

DnfTU BN

sdotsdotsdotsdot∆=

πγρκ

fHnDdTk

DfHW

TkU

UNS

BBN

sdotsdotsdot

=sdotsdotsdot

== 21302

w00 )(28242

σmicroπ

γρmicroπ

Noise voltage

1028

ln286 9minussdot

+minus= αd

DDL

Equivalent circuit diagram of an air-cored induction coil

For single turn loop Dgtgtd

Long single layer solenoid

[H] 10 H][ 10 922

9222

minusminus sdotsdotsdot

=sdotsdotsdot

asympwd

nD

w

nDL

ππ

622

10 101 46

minussdot+sdot

asympwD

nDL

922

10 10 9 3

778 minussdot++sdot

asymphwD

nDL

Short single layer solenoid wgt16D

Multi-layer solenoid Dgtgtwh

( ) 1

370

ndc

DwC r

sdotminussdotsdotsdot

=ε

1

i

2tot minus+=k

C

k

CC

Capacitance C of a coil

Capacitance C of a single-layer coil normalized to

its diameter D versus length-to-diameter ratio wD

of the coil (capacitance C in pF and geometrical

dimensions w and D in cm)

12 minuskk

High permeability core induction coil

Magnetic field pattern around high permeability core

when it is inserted into a homogeneous field It is valid

for low frequencies and if the coil indicated at the middle

of the core is without current

Magnetization of a high permeability core

dt

dnu ci

i Φ

sdotminus= ) ( cosmaxc ci tωsdotΦ=Φ

ci0rc0 maxAHnnU sdotsdotsdotsdot=Φsdotsdot= micromicroωω

HNHHHH )1( minusminus=+= micro

HN

H sdotminus+

=)1(1

1

r

i micro

irdmi HNHHHH )1( minusminus=+= micro

HfAnU sdotsdotsdotsdotsdotsdot= 0cc0 2 micromicroπ

)1(1 r

rc minus+=

micromicro

microN

minus++

minusminus=

infin1)1ln(

11

1 2

22ell mmm

m

mN

10326) (1ln 152

10156) (1ln 262

ell

cyl

++++

=infin

infin

N

N

Induction coil on a cylindrical high permeability core

Demagnetization factorDemagnetization factorN of prolate ellipsoidsand cylindrical rods(descending curves) andcore permeability μc

(ascending curves) ofcylindrical rods versusthe length-to-diameterratio m of the rod withmaterial permeability μr

as parameter

Core permeability μc of cylindrical rods versus thematerial permeability μr with length-to-diameter ratiom of the rod as parameter after

Minimum noise equivalent magnetic field spectral density of an induction coil sensor with high permeability core versus sensor weight Ws (at length-to-diameter ratios m = 50 and 100 permeability μr = 10000 of the core material and f = 1 Hz)

Induction coil sensors with electronic amplifier

II

rKLC

1=ω

II

II

RR

RK

+=

rr

2 i 1

)(

ωω

ωω

ω

D

KF

+

minus

=

+=

II

II

II

2

C

L

R

R

C

L

KD

Frequency responses of the search coil

Frequency responses of thesensitivity SA and the output voltage UA

of an induction coil sensor with a voltageamplifier at a constant magnetic fieldamplitude

Resonance step-up of thesensitivity SA at differentvalues of the damping D

Sensor with transformer coupled negative feedback to the coil

)(i)()(F

0 ωωωω FR

UMUAU A

A sdot

minus=

)( i1

)(

F

0

ωω

ω

FR

MA

FAUU A

sdot+

sdot=

Induction coil connected to a voltage amplifier with

transformer coupled negative feedback to the coil

FR

21

1K0

i1

1

i1

i )(

ωωωωωω

ωω

+sdot

+sdot=

M

RUU A

IIF2 CRL

MAf

sdotsdotsdotsdot

=∆π

Frequency response of the output voltage UA of an induction coil sensor with negative feedback transformer coupled to the coil

Applications of search coil magnetometer

Developed search coil magnetometer using amorphous ribbon

Experimental setup for the effective permeability measurement

Relative permeability depending on the numbers of ribbon(a)

and the air gap between ribbons

Relative permeability depending on the number of ribbons for the different air gap between ribbons

Relative permeability depending on the total number of ribbons for the different air gap between ribbons

10 pT

100 pT

1 pT

Noise spectrum of the developed search coil magnetometer

BJne

E xH

1minus=

neRH

1minus=

22 nP micromicro minus

Hall 효과

Bt

IRU H

HL =

2

22

)( he

eh

Hpne

nPR

micromicromicromicro

+

minus=

Rectangular Hall plate (cc1cc2 current constant sc1sc2

sensor constant I bias current U voltage drop UH Hall

voltage

Physics carrier concentration and kind of carrier measurement

Engineering magnetic field measurement

Current Measurement

Arrangement for noninvasive

current measurement using an iron

core The current to be measured

produces a proportional magnetic

field which can be measured in the

air gap

Characteristic curve produced by

the current

Arrangement for indirect noninvasive

current measurement using the

compensation principle An iron core as

represented in Figure 3-29 is held field

free by injection a current into a

compensating coil wound on the core

which offsets the field generated by the

current being measured The Hall effect

sensor in the air gap serves as a null

indicator

Circuit diagram for AC-power

measurement using a Hall effect

sensor

DC Power Measurement

Circuit diagram for DC-

power measurement using a

Hall effect sensor

Noncontact Position Sensing

Galvanomagnetic components for sensing the position of permanent magnets

and magnetically conductive materials

Current Sensor Based on Hall Sensor

and Magnetic Core for Hybrid Vehicle

KH Yeon1 SD Kim1 and D Son2 1Auto industry co14F Hanshin IT tower Guro Gu Seoul Korea2Hannam UniversityOjung dong 133 Daejeon Rep of Korea

i

Hall sensor

B

I

SB

ring core

B

I10

g

N

Bl S

micro

)( gtgtrmicro

gab core

Current Sensor Based on Hall

Sensor and Magnetic Core

Hall

Effect

Device

CurrentVoltage

applying for

Hall effect device

operation

Output

signals

Magnetic field

Occurred by

current measurement

Signal

process

circuits

Developed Current Sensor

Magnetic core

Hall sensor

PCB

25

30

35

40

45

50

Output voltage V

Current sensor(Open loop type)

Temp 25C

400A model

+400 ~ -400A

SD 000128

Linearity 003

Linearity of the sensor

Characteristics of the Current Sensors

1000A 10 V power supply

-500 -400 -300 -200 -100 0 100 200 300 400 500

00

05

10

15

20

Output voltage V

current A

Temperature 25Linearity 003

Measuring range -400A ~ +400A

1000A Electronic Load

-3

0

3

6

9

12

15

18

dB

Current sensor

DV2 PCB 24pF

40Aturns

Frequency bandwidth

Gain bandwidth 3 MHz

Current 10 A

Temperature 25

Frequency bandwidth 100 kHz

Sensor output voltage vs frequency

at applied current of 40 Aturns

1 10 100

-18

-15

-12

-9

-6

Frequency kHz 측정온도 25

주파수특성 30kHz 이상(3dB 기준)

측정전류 40Aturns(4A 10턴)

측정주파수 100Hz ~ 100kHz

Temperature 25Current 40Aturns

Frequency range 100 Hz ~ 100 kHz

What is Magnetoresistance

Magnetoresistance effect(AMR)

θθθ 2cos2

12sin12cos(

22 minusminus+∆asymp∆ xxxmx hhhRR

32 minusasymp∆ ρρ New effect GMR CMR and GMI

10 ge∆ ρρ

Two bridge configuration for

rotational angle measurement

measurement angle more than 180o

자동차 Engine Management System

Inductive and Eddy Current

Sensors Excited by Permanent Magnets

tNtU dd)( φsdotminus=

construction of an inductive

sensor (courtesy VDO Adolf sensor (courtesy VDO Adolf

Schindling AG)

1) constant socket

2) terminal package

3) permanent magnet

4) cap

5) soft magnetic core

6) coil

7) plate

8) blade connector

γγ

Sensor with yoke Change in the magnetic flux with

varying air gap Continuous lines

minimum air gap dashed lines

maximum air gap

C-shaped sensor

Sensor with radially

magnetized

permanent magnet

Signal Conditioning

Output voltage U of a DC-excited sensor with permanent

magnets when a single iron object passes by

Schematic electrical diagram of an inductive sensor

Linear Variable Differential Transformer

AC-Excited Sensors for Linear Movement

Principle of construction of an LVDT

Electrical circuit of an LVDT

tIMtNU dd dd sdotminus=sdotminus= φ

tIMtIMUUU dd dd 1212 sdotminussdot=minus=

tIMMU dd)( 12 sdotminus=

)(12 xMMMM =minus=

tIxMU dd)( sdot= tI

UxM

dd)( =

Signal Conditioning

power supply

carrier gen

autoampcontrol

LVDTcarrieramp

demod-ulator

phase

shifter

power supply

carrier gen

passivedemod-ulator

LVDTDCamp

Block diagram of a carrier amplifier system

Block diagram of a DC amplifier system

Variable Inductive Sensors

Principle of construction

of the VLP sensor

Principle of a bridge

circuit

lANL r 20 sdotsdotsdot= micromicro

21 BA UUU minus=

21)i(ii( 211 minus+sdot= LLLUU BA ωωω

)21))()((( minus∆minus+∆+∆+sdot= LLLLLLUU BA

)212)(( minus∆+sdot= LLLUU )212)(( minus∆+sdot= LLLUU BA

LLUU BA 21 ∆sdotsdot=

llLL ∆sdot=∆ d d

llLLUU BA ∆sdotsdot= d d)2(1

Applications and Properties

Principle of a construction of a force transducer

(courtesy Hottinger Baldwin Messtechnik)

Vibrationacceleration sensor

Signal Conditioning

Schematic electrical diagram of a force transducer connected with an

amplifier (courtesy Hottinger Baldwin Messtechnik GmbH)

Variable Gap Sensors

)( FeFe2

0 LLllANL micromicromicro +sdotsdot=

FeFe2

0max lANL sdotsdotsdot= micromicro

Construction of a variable gap sensor

Characteristic of a variable gap sensor

Construction of a differential

cross-anchor sensor

Output voltage U versus core

position x plusmn a limits of the

linear rage

Applications of differential cross-anchor sensors

AC-excited Sensors for Rotary Movements

Principle of construction of a synchro

α cos10 sdotsdot= UKU y

)120-( cos10 degsdotsdot= αUKU z

)240-( cos10 degsdotsdot= αUKU x

)120-( sin3100 degsdotsdotsdot=minus= αKUUUU yxyx

)240-( sin3100 degsdotsdotsdot=minus= αKUUUU zyzy

α sin3100 sdotsdotsdot=minus= KUUUU xzxz

Application to the Torque Sensor

Principle of construction of a torque-type synchro

Torque versus angular

difference

)( sin~ rt αα minussdotKM

)( cos~ rt1r αα minussdotUU

Principle of construction of a control-type sensor

Output voltage versus

angular difference

Principle of construction of a differential sychro

Eddy Current Sensors

tBE dd curl minus=JH = curl

0 div =BH(H)B sdot= micro

E(E)J sdot= σ

A B curl= A B curl=

tdd- A E =

)dd( tAJ minus= σ

tdd curl curl AA σmicro minus=

AA) σωmicro iminus= curl )(curl(1

AA) σωmicro i=∆)((1

Eddy Current Tachometer

Construction of a speedometer (courtesy VDO Adolf Schinding AG) 1) spindle 2) bearing

3) holding spring 4) iron yoke 5) eddy current cup 6) shaft of the magnet 7) support of

the magnet 8) temperature compensation 9) permanent magnet 10) torsion spring

Proximity Sensors

Schematic diagram of a proximity sensor

Output current of a proximity switch versus distance

Inductive Flowmeters

)( Btimessdot= υqF

EqF sdot=BE times=υ

)(ds Btimes== υEU )(ds Btimes== υEU

)( Bd timessdot= υU

Bsdotsdotsdot= υdKU

Development of magnetic phase detection

sensor for steam generator tube

Dirac Son1 Kwan-Sang Ryu2 Duck-Gun Park3

1Hannam University Daejeon Rep of Korea2Korea Research Institute of Standards and Science Daejeon Rep of Korea3KoreaAtomic Energy Research Institute Daejeon Rep of Korea

Introduction

The layout of pressurized water reactor (PWR) components

Primary side Secondary side (non-radioactive side)(radioactive side)

The Structure of SG(Steam Generator)(degradation mechanism)

Secondary SidePrimary Side

SCC

A B

A-B

Steam outlet

Anti-vibration

SCC

Fretting

Wall thinning

IGA

U-bend

In commercial power plants SG- height up to 21 m - weight up to 800 tons - 2~4 sets of SG were installed - SG can contain from 3000 to

16000 tubes each about 20 mmin diameter

Primary coolant outlet Primary coolant inlet

Anti-vibrationbars

Tubesupportplate

Tubesheet

IGA

SCC

Pitting

SCC

Inside Tubesheet

Top of Tubesheet

by SSHwang of KAERI

Denting

Sludge pile

in diameter

The SGT is made of nickel basedInconel alloy which is composed of 75 Ni 165Cr and 815Fe

-Degradation mechanism corrosion pitting denting inter granular attack

-Inspection Eddy current Testing(ECT)

Permeability Variation Clusters (PVC)

(Ferro-magnetic phase)

-005

000

005

010

015

m (emug)

1-1

-002

000

002

004

006

008

m (emug)

1-2

-1000 -500 0 500 1000

-015

-010

-005

H ( Am )

-1000 -500 0 500 1000

-006

-004

-002

H ( Am )

The hystresis loop in the fragment of PVC parts of Kori-1 retired SG tube

-004

-002

000

002

004

006

M (emug)

Inconel 600 tested at RT

under tensile stress

1 2 3

4 5 6

7 8 9-004

-002

000

002

004

006

M(emug)

Inconel 600 Heat treated at

602 oC under tensile stress

1 2 3

How can we detect magnetic phase

(PVC)selectively from the flaws in SGT

-3000 -2000 -1000 0 1000 2000 3000

-006

H (Oe)

7 8 9

10 11 12

-3000 -2000 -1000 0 1000 2000 3000

-006

-004

H(Oe)

4 5 6

7 8 9

The hysteresis loop of the tensile tested specimen at room temperature (a) and tensile tested at high temperature (b)

The magnetic phase can be created under the high temperature andpressure conditions which is correspond to the stress corrosion crackingin the SG tube in the NPP(Bruemmer SM Charlot LA amp Henager CH (1988) Corrosion 782)

Principle of ECT

If we can separate magnetic phase selectively from the

flaws using magnetic sensor the reliability of EC in SGT

inspection will be greatly enhanced

Structure of the permeability

sensor

Dimension and photograph of U-shape

sensing yoke

Design of Magnetic Sensor for PVC

sensor sensing yoke

Photograph of the completed sensor front side (above) and rear side (bottom)

R11R12

R10

R8

R6

R9

R13

R7

R14

C18

1 n

C17

C20

C21

D2

DIODE

SIN COS

-

+

U-2A

4

13

2

-

+

U-2B

75

6

8

-

+

U-3A

13

2

8

+5VC19

104

+5V

Schematic diagram of the sensor system

Electronic Circuit of Magnetic Sensor

R20

R

R21

R

-

+

U5AD797

3

26

74

U6

D1

S12

GND3

+VCC4VCC5

IN6

-VCC7

S28

C41

R13

R26

R18

R25

R2210 Ω

R16

R14

R17

10 k

R15

R27

R32

R28

R33

R29

R34

5 k

R30

C29

C37

104

C32473

C39473C40

104

C33

104

C21

104C23

104

C25

104

C26

104

C30

104

C31

104

C35

104

C36

104

C27

104

C28

104

C34

104

C38

104

D3

DIODE

L1

1

2

L2

1

2

L3

1

2

4

-

+

U-4A

4

13

2

-

+

U-4B

75

6

8

-

+

U-5A

4

13

2

-

+

U-5B

75

6

8

-

+

U-6A

4

13

2

-

+

U-6B

75

6

8

C22

104

-5V

+5V

+5V

+5V

+5V

+5V

+5V

U7

D1

S12

GND3

+VCC4

VCC5

IN6

-VCC7

S28

+5V

-5V

-5V

-5V

-5V

-5V

-5V

-5V

-5V

R19

R24

R

R23

R

C24

OUT(X)

OUT(Y)

R1

20 kR210 k

R3

20 kR410 k

C1

104

C8

104

REF43

OUT(X)

OUT(Y)

REF43

U2

+Vcc1

CH02

CH13

CH24

CH35

COMM6

SHDN7

Vref8

+Vcc9

GND10

GND11

DOUT12BUSY13DIN14CS15

DIN16

-

+

U-1A

13

2

8

-

+

U-1B

4

75

6

C410 uF

C5104

DOUT

C210uF

C6104

C3104

DCLK

C7104

DIN

C10

01uF

CS

BUSY

C14 10uF

J1

CON6

123456

D1

DIODE

R5

47K

C9

10uF

C1310uF

Y1

OSC

OUT3

GND2

VCC4

U3

RSTVPP1

GND10

VCC20

XTAL15

XTAL24

P10AIN012P11AIN113P1214P1315P1416P1517P1618P1719

P30RXD2

P31TXD3

P32INT06

P33INT17

P34T08

P35T19

P3711

U4

C1+1

C1-3

C2+4

C2-5

VCC16

GND15

V+2

V-6

R1OUT12

R2OUT9

T1IN11

T2IN10

R1IN13

R2IN8

T1OUT14

T2OUT7

C12 10uF

C16

01uF

C15 10uF

C11

01uF

-5V

+5V

+5V

+5V

+5V

+5V

+5V

+5V

RST

OSC

OSC

RST

DCLKCSDINBUSYDOUT

U1

IN2

GND

4

OUT6

TEMP3

TRIM5

-5V

+5V

Electronic circuit diagram of the magnetic sensor

Photograph of the completed measuring system data acquisition

software in PC and probe scanning system

Experimental Setup for Magnetic Sensor

Reference material Scanning System Software LabVIEW

Reference Material (1) Normal defects and PVCs

Longitudinal and transverse defects

Def W L D Remarks

1 02 500 0213 (20 ) Inner defects

2 02 500 0427 (40 )

3 02 500 0213 (20 )Outer defectsPVC(1018)4 02 500 0427 (40 )

5 02 500 0639 (60 )

6 02 500 0852 (80 )

7 02 500 0639 (60 ) Inner defects

8 02 500 0852 (80 )

- 1 and 2 are inner defects

- 345 and 6 are outer defects with PVC

- 7 and 8 are inner defects

PVC

PVC

Defect Defect

For longitudinal defects and PVC For circumferential defects and PVC

ECT is very difficult to detect circumferential defects

We can distinguish PVCs and defects and longitudinal and circumferential defects

Flux-gate Magnetometer

One core sensor Two core sensor

3-축 flux-gate Magnetometer의 계략도

Sensorpia Co

pro

cess

or(

AV

R)

Sensor 1

RS422

Interface

Mic

ro-p

roce

ssor(

AV

R)

Sensor 2

Sensor 3

Interface

조립된 마그네토미터의 사진

Sensorpia Co

Analog PCB

Digital PCB

Sensorpia Co선형도(linearity)

10

20

30

40

50

60

y-axis

Magnetometer Output (microT)

-60 -50 -40 -30 -20 -10 0 10 20 30 40 50 60

-60

-50

-40

-30

-20

-10

0

10

Y-axis y=099946 x+0015STD 106E-4

Magnetometer Output (

Applied Magnetic Field (microT)

마그네토미터의 noise 특성 Sensorpia Co

1

10

100

y-axis

Magnetometer noise (nT)

0 1 2 3 4 5 6

1E-4

1E-3

001

01

Magnetometer noise (nT)

Frequency (Hz)

Magnetometer for KoDSAT

-150 -100 -50 0 50 100 150

-15

-10

-5

0

5

10

15

Magnetic Moment (Am

2)

Current (mA)

After Thermal Cycle Test

Measured

Resistance 193 ohm

Photograph of Magnetic torquer

Photograph of KoDSAT

Photograph of

3-axis Fluxgate

Magnetometer

Photograph of Magnetic torquer

Application of magnetometer

Moon magnetic fieldmeasurement

Telescope with direction indication

Joule Effect (Magnetostriction)

ϕ2cosel

l=

∆

0=∆

+∆

+∆

b

b

a

a

l

l

Actuator using Terfenol-D

00

05

10

B (T)

800

1000

1200

1400

1600

Magnetostriction (ppm)

-100 -50 0 50 100

-10

-05

00

B (T)

H (kAm)

2 MPa

4 MPa

6 MPa

8 MPa

10 MPa

12 MPa

-100 -50 0 50 100

-200

0

200

400

600

Magnetostriction (ppm)

H (kAm)

2 MPa

4 MPa

6 MPa

8 MPa

10 MPa

12 MPa

600

700

800

900

1000

-4 -3 -2 -1 0 1 2 3 4

0

10

20

30

40

50

60

Displacement (m

icro meter)

I (A)

FIELD

9 kAm

12 kAm

16 kAm

20 kAm

24 kAm

38 kAm

-50 -40 -30 -20 -10 0 10 20 30 40 50

-100

0

100

200

300

400

500

L (PPM)

H (kAm)

9 kAm

12 kAm

16 kAm

20 kAm

24 kAm

38 kAm

Magnetostrictive displacement sensor

Hysteresis loops under

tensile stress σ

(a) Crystalline 68 NiFe

λs = +25 10-6

(b) crystalline pure Ni λs

= -35 10-6

Villari Effect ( Inverse of Joule Effect)

= -35 10-6

(c) amorphous Co-based

alloy

λs = -35 10-6

ϕσλ 2sin2

3sdotsdot= smeE

γ

Permeability depending on the stress

σλmicromicro

1

3

2

Y

J

so

s

r =

γ

Calculated magnetization curves under stress

Variation of magnetization curve by an applied

tensile force (Co-based amorphous alloy)

Alloy Requirement

Materials for magnetoelastic sensors

Why amorphous magnetic materials are important

Stress-strain curves of several materials

Coercivity and hardness of several materials

Principles of magnetoelastic sensors

Non-contact torque sensor

Principle of cross torductor torque

sensor and flux pattern of sensor

poles on the surface of a shaft

a) without and b)with torsional load

Equivalent magnetic circuit of

cross type torque sensor

Helices of principal tensile and compressive stress on the surface of

a shaft subjected to torsion [32] Correlated changes of permeability

are detected by four-branch yoke system with sensing coils 123

and 4 and a common excitation pole

Examples of torque sensors

Four-branch type torque sensor

heads Pole structures realized

by commercial multi-pole

ferrites 14 and 18 min in

diameter (diameter of sensor

h e a d 1 7 a n d 2 4 m m

respectively) respectively)

Principle of Ring Torductor torque transducer

(a b) Physical structure (c) evolution of the

shaft surface under the transducer poles A and BRing torductor for measuring

torque on ship propeller shafts

(shaft diameter ca 500 mm)

(Courtesy ASEA Brown

Boveri AG)

Principal designs of coaxial torque sensors

Schematic diagram of data processing

electronics of a torque sensor

Extensometer (a) Construction of strain sensing element using

amorphous ribbon wound core (b) configuration of lumped

windings

∆E effect of an amorphous FeNi-based

alloy (Fe40 Ni38 Mo4 B18) Hs saturation

field

Magnetically tunable delay line

Torque Sensors using Amorphous wire

Sixtus tonk효과(large Barkhausen효과)

Hysteresis loops of a Wiegand wire for different reset fields

Curie 온도 및Hopkinson효과

Relation between normalised

saturation polarisation and

normalised Curie temperature

Permeability of a Mn-Zn ferrite as

a function of temperature and field

strength

Conclusions

1) Magnetic sensor 는 자동차 공장자동화 항공우주 및 군사용으로많이 사용되고 있다

2) 새로운 소재개발은 자기센서의 성능개발에 직접적인 영향을 준다2) 새로운 소재개발은 자기센서의 성능개발에 직접적인 영향을 준다

3) 센서의 개발을 위해서는 다양한 전공지식이 요구된다

(물리학 재료공학 기계공학 전자공학)

4) 센서분야가 고부가가치를 창출하는 부품사업이다

5) 핵심부품을 생산하는 중소기업의 item으로도 적절하다

Magnetic Effects for SensorsYear Effect Explanation Technical Use

1842 Joule effect Change in shape of a ferromagnetic body with magnetization (magnetostriction)

In combination with piezoelectric elements for magnetometers and potentiometers

1846 ΔE effect Chang in Youngrsquos modulus with magnetization Acoustic delay line components for magnetic field measurement

1847 Matteucci effect Torsion of a ferromagnetic rod in a longitudinal field changes magnetization

Magnetoelastic sensor

1856 Magnetoresistance

(AMR)

Change in resistance with magnetic field Magnetoresistive sensors

1858 Wiedemann effect A torsion is produced in a current carrying ferromagnetic rod when subjected to a longitudinal field

Torque and force measurement

1865 Villari effect Effect on magnetization by tensile or compressive strength

Magnetoelastic sensorsstrength

1879 Hall effect A current carrying crystal produces a transverse voltage when subjected to a magnetic field vertical to its surface

Magnetogalvanic sensors

1903 Skin effect Displacement of current from the interior of material to surface layer due to eddy currents

Distance sensors proximity sensors

1931 Sixtus Tonks effect Pulse magnetization by large Barkhausen jumps Wiegand and pulse-wire sensors

1962 Josephson effect Tunnel effect between two superconducting materials with an extremely thin separating layer quantum effect

SQUID magnetometers

1987 GMR effect Quantum mechanical magnetoresistance effect observed in thin-film structures composed of alternating ferromagnetic and non-magnetic conductive layers

Magnetic field sensor

Sprintonics

1994 GMI effect Large variations that the electrical impedance of some materials exhibits as a function of an external magnetic field

Magnetic field sensor

Principle of search coil type magnetometerPrinciple of search coil type magnetometer

int intint sdotminus=sdotA

ABt

sE d d

dd

Faradayrsquos Induction Law

Faraday 전자기유도법칙

Atd

HAnnU sdotsdotsdotsdot=Φsdotsdot= microωω max0

Voltage output from magnetometer

Sensitivity and Noise of Air Cored Induction Coil

HfDnHAnnU sdotsdotsdotsdotsdot=sdotsdotsdotsdot=Φsdotsdot= 02

2

0max02

microπ

microωω

2

022

00

microπ sdotsdot=

sdot=

Dn

Hf

US

V2π

sdotsdot=

sdotsdot

sdot= minus2

-970

m Hz nT

V10

m A

S V104πmicro

sdot

sdotsdot= minus

Hz nT

V10

2

922

0 DnUπ

Air-cored induction coil in a time-varying magnetic field

sdot

sdotsdot= minus

Hz nT

V10

2

922

0 DnUπ

Air-cored coil output voltage U0 at a magnetic field x frequency product

1 nT middot Hz versus diameter D with number of turns n as parameter

4

22 dDnWW

sdotsdotsdotsdot=

γπ Weight of coil

Coil resistance2

4

d

nDRDC

ρ=

Thermal voltage noisefTRU DCBN ∆= κ4

W

4W

DnfTU BN

sdotsdotsdotsdot∆=

πγρκ

fHnDdTk

DfHW

TkU

UNS

BBN

sdotsdotsdot

=sdotsdotsdot

== 21302

w00 )(28242

σmicroπ

γρmicroπ

Noise voltage

1028

ln286 9minussdot

+minus= αd

DDL

Equivalent circuit diagram of an air-cored induction coil

For single turn loop Dgtgtd

Long single layer solenoid

[H] 10 H][ 10 922

9222

minusminus sdotsdotsdot

=sdotsdotsdot

asympwd

nD

w

nDL

ππ

622

10 101 46

minussdot+sdot

asympwD

nDL

922

10 10 9 3

778 minussdot++sdot

asymphwD

nDL

Short single layer solenoid wgt16D

Multi-layer solenoid Dgtgtwh

( ) 1

370

ndc

DwC r

sdotminussdotsdotsdot

=ε

1

i

2tot minus+=k

C

k

CC

Capacitance C of a coil

Capacitance C of a single-layer coil normalized to

its diameter D versus length-to-diameter ratio wD

of the coil (capacitance C in pF and geometrical

dimensions w and D in cm)

12 minuskk

High permeability core induction coil

Magnetic field pattern around high permeability core

when it is inserted into a homogeneous field It is valid

for low frequencies and if the coil indicated at the middle

of the core is without current

Magnetization of a high permeability core

dt

dnu ci

i Φ

sdotminus= ) ( cosmaxc ci tωsdotΦ=Φ

ci0rc0 maxAHnnU sdotsdotsdotsdot=Φsdotsdot= micromicroωω

HNHHHH )1( minusminus=+= micro

HN

H sdotminus+

=)1(1

1

r

i micro

irdmi HNHHHH )1( minusminus=+= micro

HfAnU sdotsdotsdotsdotsdotsdot= 0cc0 2 micromicroπ

)1(1 r

rc minus+=

micromicro

microN

minus++

minusminus=

infin1)1ln(

11

1 2

22ell mmm

m

mN

10326) (1ln 152

10156) (1ln 262

ell

cyl

++++

=infin

infin

N

N

Induction coil on a cylindrical high permeability core

Demagnetization factorDemagnetization factorN of prolate ellipsoidsand cylindrical rods(descending curves) andcore permeability μc

(ascending curves) ofcylindrical rods versusthe length-to-diameterratio m of the rod withmaterial permeability μr

as parameter

Core permeability μc of cylindrical rods versus thematerial permeability μr with length-to-diameter ratiom of the rod as parameter after

Minimum noise equivalent magnetic field spectral density of an induction coil sensor with high permeability core versus sensor weight Ws (at length-to-diameter ratios m = 50 and 100 permeability μr = 10000 of the core material and f = 1 Hz)

Induction coil sensors with electronic amplifier

II

rKLC

1=ω

II

II

RR

RK

+=

rr

2 i 1

)(

ωω

ωω

ω

D

KF

+

minus

=

+=

II

II

II

2

C

L

R

R

C

L

KD

Frequency responses of the search coil

Frequency responses of thesensitivity SA and the output voltage UA

of an induction coil sensor with a voltageamplifier at a constant magnetic fieldamplitude

Resonance step-up of thesensitivity SA at differentvalues of the damping D

Sensor with transformer coupled negative feedback to the coil

)(i)()(F

0 ωωωω FR

UMUAU A

A sdot

minus=

)( i1

)(

F

0

ωω

ω

FR

MA

FAUU A

sdot+

sdot=

Induction coil connected to a voltage amplifier with

transformer coupled negative feedback to the coil

FR

21

1K0

i1

1

i1

i )(

ωωωωωω

ωω

+sdot

+sdot=

M

RUU A

IIF2 CRL

MAf

sdotsdotsdotsdot

=∆π

Frequency response of the output voltage UA of an induction coil sensor with negative feedback transformer coupled to the coil

Applications of search coil magnetometer

Developed search coil magnetometer using amorphous ribbon

Experimental setup for the effective permeability measurement

Relative permeability depending on the numbers of ribbon(a)

and the air gap between ribbons

Relative permeability depending on the number of ribbons for the different air gap between ribbons

Relative permeability depending on the total number of ribbons for the different air gap between ribbons

10 pT

100 pT

1 pT

Noise spectrum of the developed search coil magnetometer

BJne

E xH

1minus=

neRH

1minus=

22 nP micromicro minus

Hall 효과

Bt

IRU H

HL =

2

22

)( he

eh

Hpne

nPR

micromicromicromicro

+

minus=

Rectangular Hall plate (cc1cc2 current constant sc1sc2

sensor constant I bias current U voltage drop UH Hall

voltage

Physics carrier concentration and kind of carrier measurement

Engineering magnetic field measurement

Current Measurement

Arrangement for noninvasive

current measurement using an iron

core The current to be measured

produces a proportional magnetic

field which can be measured in the

air gap

Characteristic curve produced by

the current

Arrangement for indirect noninvasive

current measurement using the

compensation principle An iron core as

represented in Figure 3-29 is held field

free by injection a current into a

compensating coil wound on the core

which offsets the field generated by the

current being measured The Hall effect

sensor in the air gap serves as a null

indicator

Circuit diagram for AC-power

measurement using a Hall effect

sensor

DC Power Measurement

Circuit diagram for DC-

power measurement using a

Hall effect sensor

Noncontact Position Sensing

Galvanomagnetic components for sensing the position of permanent magnets

and magnetically conductive materials

Current Sensor Based on Hall Sensor

and Magnetic Core for Hybrid Vehicle

KH Yeon1 SD Kim1 and D Son2 1Auto industry co14F Hanshin IT tower Guro Gu Seoul Korea2Hannam UniversityOjung dong 133 Daejeon Rep of Korea

i

Hall sensor

B

I

SB

ring core

B

I10

g

N

Bl S

micro

)( gtgtrmicro

gab core

Current Sensor Based on Hall

Sensor and Magnetic Core

Hall

Effect

Device

CurrentVoltage

applying for

Hall effect device

operation

Output

signals

Magnetic field

Occurred by

current measurement

Signal

process

circuits

Developed Current Sensor

Magnetic core

Hall sensor

PCB

25

30

35

40

45

50

Output voltage V

Current sensor(Open loop type)

Temp 25C

400A model

+400 ~ -400A

SD 000128

Linearity 003

Linearity of the sensor

Characteristics of the Current Sensors

1000A 10 V power supply

-500 -400 -300 -200 -100 0 100 200 300 400 500

00

05

10

15

20

Output voltage V

current A

Temperature 25Linearity 003

Measuring range -400A ~ +400A

1000A Electronic Load

-3

0

3

6

9

12

15

18

dB

Current sensor

DV2 PCB 24pF

40Aturns

Frequency bandwidth

Gain bandwidth 3 MHz

Current 10 A

Temperature 25

Frequency bandwidth 100 kHz

Sensor output voltage vs frequency

at applied current of 40 Aturns

1 10 100

-18

-15

-12

-9

-6

Frequency kHz 측정온도 25

주파수특성 30kHz 이상(3dB 기준)

측정전류 40Aturns(4A 10턴)

측정주파수 100Hz ~ 100kHz

Temperature 25Current 40Aturns

Frequency range 100 Hz ~ 100 kHz

What is Magnetoresistance

Magnetoresistance effect(AMR)

θθθ 2cos2

12sin12cos(

22 minusminus+∆asymp∆ xxxmx hhhRR

32 minusasymp∆ ρρ New effect GMR CMR and GMI

10 ge∆ ρρ

Two bridge configuration for

rotational angle measurement

measurement angle more than 180o

자동차 Engine Management System

Inductive and Eddy Current

Sensors Excited by Permanent Magnets

tNtU dd)( φsdotminus=

construction of an inductive

sensor (courtesy VDO Adolf sensor (courtesy VDO Adolf

Schindling AG)

1) constant socket

2) terminal package

3) permanent magnet

4) cap

5) soft magnetic core

6) coil

7) plate

8) blade connector

γγ

Sensor with yoke Change in the magnetic flux with

varying air gap Continuous lines

minimum air gap dashed lines

maximum air gap

C-shaped sensor

Sensor with radially

magnetized

permanent magnet

Signal Conditioning

Output voltage U of a DC-excited sensor with permanent

magnets when a single iron object passes by

Schematic electrical diagram of an inductive sensor

Linear Variable Differential Transformer

AC-Excited Sensors for Linear Movement

Principle of construction of an LVDT

Electrical circuit of an LVDT

tIMtNU dd dd sdotminus=sdotminus= φ

tIMtIMUUU dd dd 1212 sdotminussdot=minus=

tIMMU dd)( 12 sdotminus=

)(12 xMMMM =minus=

tIxMU dd)( sdot= tI

UxM

dd)( =

Signal Conditioning

power supply

carrier gen

autoampcontrol

LVDTcarrieramp

demod-ulator

phase

shifter

power supply

carrier gen

passivedemod-ulator

LVDTDCamp

Block diagram of a carrier amplifier system

Block diagram of a DC amplifier system

Variable Inductive Sensors

Principle of construction

of the VLP sensor

Principle of a bridge

circuit

lANL r 20 sdotsdotsdot= micromicro

21 BA UUU minus=

21)i(ii( 211 minus+sdot= LLLUU BA ωωω

)21))()((( minus∆minus+∆+∆+sdot= LLLLLLUU BA

)212)(( minus∆+sdot= LLLUU )212)(( minus∆+sdot= LLLUU BA

LLUU BA 21 ∆sdotsdot=

llLL ∆sdot=∆ d d

llLLUU BA ∆sdotsdot= d d)2(1

Applications and Properties

Principle of a construction of a force transducer

(courtesy Hottinger Baldwin Messtechnik)

Vibrationacceleration sensor

Signal Conditioning

Schematic electrical diagram of a force transducer connected with an

amplifier (courtesy Hottinger Baldwin Messtechnik GmbH)

Variable Gap Sensors

)( FeFe2

0 LLllANL micromicromicro +sdotsdot=

FeFe2

0max lANL sdotsdotsdot= micromicro

Construction of a variable gap sensor

Characteristic of a variable gap sensor

Construction of a differential

cross-anchor sensor

Output voltage U versus core

position x plusmn a limits of the

linear rage

Applications of differential cross-anchor sensors

AC-excited Sensors for Rotary Movements

Principle of construction of a synchro

α cos10 sdotsdot= UKU y

)120-( cos10 degsdotsdot= αUKU z

)240-( cos10 degsdotsdot= αUKU x

)120-( sin3100 degsdotsdotsdot=minus= αKUUUU yxyx

)240-( sin3100 degsdotsdotsdot=minus= αKUUUU zyzy

α sin3100 sdotsdotsdot=minus= KUUUU xzxz

Application to the Torque Sensor

Principle of construction of a torque-type synchro

Torque versus angular

difference

)( sin~ rt αα minussdotKM

)( cos~ rt1r αα minussdotUU

Principle of construction of a control-type sensor

Output voltage versus

angular difference

Principle of construction of a differential sychro

Eddy Current Sensors

tBE dd curl minus=JH = curl

0 div =BH(H)B sdot= micro

E(E)J sdot= σ

A B curl= A B curl=

tdd- A E =

)dd( tAJ minus= σ

tdd curl curl AA σmicro minus=

AA) σωmicro iminus= curl )(curl(1

AA) σωmicro i=∆)((1

Eddy Current Tachometer

Construction of a speedometer (courtesy VDO Adolf Schinding AG) 1) spindle 2) bearing

3) holding spring 4) iron yoke 5) eddy current cup 6) shaft of the magnet 7) support of

the magnet 8) temperature compensation 9) permanent magnet 10) torsion spring

Proximity Sensors

Schematic diagram of a proximity sensor

Output current of a proximity switch versus distance

Inductive Flowmeters

)( Btimessdot= υqF

EqF sdot=BE times=υ

)(ds Btimes== υEU )(ds Btimes== υEU

)( Bd timessdot= υU

Bsdotsdotsdot= υdKU

Development of magnetic phase detection

sensor for steam generator tube

Dirac Son1 Kwan-Sang Ryu2 Duck-Gun Park3

1Hannam University Daejeon Rep of Korea2Korea Research Institute of Standards and Science Daejeon Rep of Korea3KoreaAtomic Energy Research Institute Daejeon Rep of Korea

Introduction

The layout of pressurized water reactor (PWR) components

Primary side Secondary side (non-radioactive side)(radioactive side)

The Structure of SG(Steam Generator)(degradation mechanism)

Secondary SidePrimary Side

SCC

A B

A-B

Steam outlet

Anti-vibration

SCC

Fretting

Wall thinning

IGA

U-bend

In commercial power plants SG- height up to 21 m - weight up to 800 tons - 2~4 sets of SG were installed - SG can contain from 3000 to

16000 tubes each about 20 mmin diameter

Primary coolant outlet Primary coolant inlet

Anti-vibrationbars

Tubesupportplate

Tubesheet

IGA

SCC

Pitting

SCC

Inside Tubesheet

Top of Tubesheet

by SSHwang of KAERI

Denting

Sludge pile

in diameter

The SGT is made of nickel basedInconel alloy which is composed of 75 Ni 165Cr and 815Fe

-Degradation mechanism corrosion pitting denting inter granular attack

-Inspection Eddy current Testing(ECT)

Permeability Variation Clusters (PVC)

(Ferro-magnetic phase)

-005

000

005

010

015

m (emug)

1-1

-002

000

002

004

006

008

m (emug)

1-2

-1000 -500 0 500 1000

-015

-010

-005

H ( Am )

-1000 -500 0 500 1000

-006

-004

-002

H ( Am )

The hystresis loop in the fragment of PVC parts of Kori-1 retired SG tube

-004

-002

000

002

004

006

M (emug)

Inconel 600 tested at RT

under tensile stress

1 2 3

4 5 6

7 8 9-004

-002

000

002

004

006

M(emug)

Inconel 600 Heat treated at

602 oC under tensile stress

1 2 3

How can we detect magnetic phase

(PVC)selectively from the flaws in SGT

-3000 -2000 -1000 0 1000 2000 3000

-006

H (Oe)

7 8 9

10 11 12

-3000 -2000 -1000 0 1000 2000 3000

-006

-004

H(Oe)

4 5 6

7 8 9

The hysteresis loop of the tensile tested specimen at room temperature (a) and tensile tested at high temperature (b)

The magnetic phase can be created under the high temperature andpressure conditions which is correspond to the stress corrosion crackingin the SG tube in the NPP(Bruemmer SM Charlot LA amp Henager CH (1988) Corrosion 782)

Principle of ECT

If we can separate magnetic phase selectively from the

flaws using magnetic sensor the reliability of EC in SGT

inspection will be greatly enhanced

Structure of the permeability

sensor

Dimension and photograph of U-shape

sensing yoke

Design of Magnetic Sensor for PVC

sensor sensing yoke

Photograph of the completed sensor front side (above) and rear side (bottom)

R11R12

R10

R8

R6

R9

R13

R7

R14

C18

1 n

C17

C20

C21

D2

DIODE

SIN COS

-

+

U-2A

4

13

2

-

+

U-2B

75

6

8

-

+

U-3A

13

2

8

+5VC19

104

+5V

Schematic diagram of the sensor system

Electronic Circuit of Magnetic Sensor

R20

R

R21

R

-

+

U5AD797

3

26

74

U6

D1

S12

GND3

+VCC4VCC5

IN6

-VCC7

S28

C41

R13

R26

R18

R25

R2210 Ω

R16

R14

R17

10 k

R15

R27

R32

R28

R33

R29

R34

5 k

R30

C29

C37

104

C32473

C39473C40

104

C33

104

C21

104C23

104

C25

104

C26

104

C30

104

C31

104

C35

104

C36

104

C27

104

C28

104

C34

104

C38

104

D3

DIODE

L1

1

2

L2

1

2

L3

1

2

4

-

+

U-4A

4

13

2

-

+

U-4B

75

6

8

-

+

U-5A

4

13

2

-

+

U-5B

75

6

8

-

+

U-6A

4

13

2

-

+

U-6B

75

6

8

C22

104

-5V

+5V

+5V

+5V

+5V

+5V

+5V

U7

D1

S12

GND3

+VCC4

VCC5

IN6

-VCC7

S28

+5V

-5V

-5V

-5V

-5V

-5V

-5V

-5V

-5V

R19

R24

R

R23

R

C24

OUT(X)

OUT(Y)

R1

20 kR210 k

R3

20 kR410 k

C1

104

C8

104

REF43

OUT(X)

OUT(Y)

REF43

U2

+Vcc1

CH02

CH13

CH24

CH35

COMM6

SHDN7

Vref8

+Vcc9

GND10

GND11

DOUT12BUSY13DIN14CS15

DIN16

-

+

U-1A

13

2

8

-

+

U-1B

4

75

6

C410 uF

C5104

DOUT

C210uF

C6104

C3104

DCLK

C7104

DIN

C10

01uF

CS

BUSY

C14 10uF

J1

CON6

123456

D1

DIODE

R5

47K

C9

10uF

C1310uF

Y1

OSC

OUT3

GND2

VCC4

U3

RSTVPP1

GND10

VCC20

XTAL15

XTAL24

P10AIN012P11AIN113P1214P1315P1416P1517P1618P1719

P30RXD2

P31TXD3

P32INT06

P33INT17

P34T08

P35T19

P3711

U4

C1+1

C1-3

C2+4

C2-5

VCC16

GND15

V+2

V-6

R1OUT12

R2OUT9

T1IN11

T2IN10

R1IN13

R2IN8

T1OUT14

T2OUT7

C12 10uF

C16

01uF

C15 10uF

C11

01uF

-5V

+5V

+5V

+5V

+5V

+5V

+5V

+5V

RST

OSC

OSC

RST

DCLKCSDINBUSYDOUT

U1

IN2

GND

4

OUT6

TEMP3

TRIM5

-5V

+5V

Electronic circuit diagram of the magnetic sensor

Photograph of the completed measuring system data acquisition

software in PC and probe scanning system

Experimental Setup for Magnetic Sensor

Reference material Scanning System Software LabVIEW

Reference Material (1) Normal defects and PVCs

Longitudinal and transverse defects

Def W L D Remarks

1 02 500 0213 (20 ) Inner defects

2 02 500 0427 (40 )

3 02 500 0213 (20 )Outer defectsPVC(1018)4 02 500 0427 (40 )

5 02 500 0639 (60 )

6 02 500 0852 (80 )

7 02 500 0639 (60 ) Inner defects

8 02 500 0852 (80 )

- 1 and 2 are inner defects

- 345 and 6 are outer defects with PVC

- 7 and 8 are inner defects

PVC

PVC

Defect Defect

For longitudinal defects and PVC For circumferential defects and PVC

ECT is very difficult to detect circumferential defects

We can distinguish PVCs and defects and longitudinal and circumferential defects

Flux-gate Magnetometer

One core sensor Two core sensor

3-축 flux-gate Magnetometer의 계략도

Sensorpia Co

pro

cess

or(

AV

R)

Sensor 1

RS422

Interface

Mic

ro-p

roce

ssor(

AV

R)

Sensor 2

Sensor 3

Interface

조립된 마그네토미터의 사진

Sensorpia Co

Analog PCB

Digital PCB

Sensorpia Co선형도(linearity)

10

20

30

40

50

60

y-axis

Magnetometer Output (microT)

-60 -50 -40 -30 -20 -10 0 10 20 30 40 50 60

-60

-50

-40

-30

-20

-10

0

10

Y-axis y=099946 x+0015STD 106E-4

Magnetometer Output (

Applied Magnetic Field (microT)

마그네토미터의 noise 특성 Sensorpia Co

1

10

100

y-axis

Magnetometer noise (nT)

0 1 2 3 4 5 6

1E-4

1E-3

001

01

Magnetometer noise (nT)

Frequency (Hz)

Magnetometer for KoDSAT

-150 -100 -50 0 50 100 150

-15

-10

-5

0

5

10

15

Magnetic Moment (Am

2)

Current (mA)

After Thermal Cycle Test

Measured

Resistance 193 ohm

Photograph of Magnetic torquer

Photograph of KoDSAT

Photograph of

3-axis Fluxgate

Magnetometer

Photograph of Magnetic torquer

Application of magnetometer

Moon magnetic fieldmeasurement

Telescope with direction indication

Joule Effect (Magnetostriction)

ϕ2cosel

l=

∆

0=∆

+∆

+∆

b

b

a

a

l

l

Actuator using Terfenol-D

00

05

10

B (T)

800

1000

1200

1400

1600

Magnetostriction (ppm)

-100 -50 0 50 100

-10

-05

00

B (T)

H (kAm)

2 MPa

4 MPa

6 MPa

8 MPa

10 MPa

12 MPa

-100 -50 0 50 100

-200

0

200

400

600

Magnetostriction (ppm)

H (kAm)

2 MPa

4 MPa

6 MPa

8 MPa

10 MPa

12 MPa

600

700

800

900

1000

-4 -3 -2 -1 0 1 2 3 4

0

10

20

30

40

50

60

Displacement (m

icro meter)

I (A)

FIELD

9 kAm

12 kAm

16 kAm

20 kAm

24 kAm

38 kAm

-50 -40 -30 -20 -10 0 10 20 30 40 50

-100

0

100

200

300

400

500

L (PPM)

H (kAm)

9 kAm

12 kAm

16 kAm

20 kAm

24 kAm

38 kAm

Magnetostrictive displacement sensor

Hysteresis loops under

tensile stress σ

(a) Crystalline 68 NiFe

λs = +25 10-6

(b) crystalline pure Ni λs

= -35 10-6

Villari Effect ( Inverse of Joule Effect)

= -35 10-6

(c) amorphous Co-based

alloy

λs = -35 10-6

ϕσλ 2sin2

3sdotsdot= smeE

γ

Permeability depending on the stress

σλmicromicro

1

3

2

Y

J

so

s

r =

γ

Calculated magnetization curves under stress

Variation of magnetization curve by an applied

tensile force (Co-based amorphous alloy)

Alloy Requirement

Materials for magnetoelastic sensors

Why amorphous magnetic materials are important

Stress-strain curves of several materials

Coercivity and hardness of several materials

Principles of magnetoelastic sensors

Non-contact torque sensor

Principle of cross torductor torque

sensor and flux pattern of sensor

poles on the surface of a shaft

a) without and b)with torsional load

Equivalent magnetic circuit of

cross type torque sensor

Helices of principal tensile and compressive stress on the surface of

a shaft subjected to torsion [32] Correlated changes of permeability

are detected by four-branch yoke system with sensing coils 123

and 4 and a common excitation pole

Examples of torque sensors

Four-branch type torque sensor

heads Pole structures realized

by commercial multi-pole

ferrites 14 and 18 min in

diameter (diameter of sensor

h e a d 1 7 a n d 2 4 m m

respectively) respectively)

Principle of Ring Torductor torque transducer

(a b) Physical structure (c) evolution of the

shaft surface under the transducer poles A and BRing torductor for measuring

torque on ship propeller shafts

(shaft diameter ca 500 mm)

(Courtesy ASEA Brown

Boveri AG)

Principal designs of coaxial torque sensors

Schematic diagram of data processing

electronics of a torque sensor

Extensometer (a) Construction of strain sensing element using

amorphous ribbon wound core (b) configuration of lumped

windings

∆E effect of an amorphous FeNi-based

alloy (Fe40 Ni38 Mo4 B18) Hs saturation

field

Magnetically tunable delay line

Torque Sensors using Amorphous wire

Sixtus tonk효과(large Barkhausen효과)

Hysteresis loops of a Wiegand wire for different reset fields

Curie 온도 및Hopkinson효과

Relation between normalised

saturation polarisation and

normalised Curie temperature

Permeability of a Mn-Zn ferrite as

a function of temperature and field

strength

Conclusions

1) Magnetic sensor 는 자동차 공장자동화 항공우주 및 군사용으로많이 사용되고 있다

2) 새로운 소재개발은 자기센서의 성능개발에 직접적인 영향을 준다2) 새로운 소재개발은 자기센서의 성능개발에 직접적인 영향을 준다

3) 센서의 개발을 위해서는 다양한 전공지식이 요구된다

(물리학 재료공학 기계공학 전자공학)

4) 센서분야가 고부가가치를 창출하는 부품사업이다

5) 핵심부품을 생산하는 중소기업의 item으로도 적절하다

Principle of search coil type magnetometerPrinciple of search coil type magnetometer

int intint sdotminus=sdotA

ABt

sE d d

dd

Faradayrsquos Induction Law

Faraday 전자기유도법칙

Atd

HAnnU sdotsdotsdotsdot=Φsdotsdot= microωω max0

Voltage output from magnetometer

Sensitivity and Noise of Air Cored Induction Coil

HfDnHAnnU sdotsdotsdotsdotsdot=sdotsdotsdotsdot=Φsdotsdot= 02

2

0max02

microπ

microωω

2

022

00

microπ sdotsdot=

sdot=

Dn

Hf

US

V2π

sdotsdot=

sdotsdot

sdot= minus2

-970

m Hz nT

V10

m A

S V104πmicro

sdot

sdotsdot= minus

Hz nT

V10

2

922

0 DnUπ

Air-cored induction coil in a time-varying magnetic field

sdot

sdotsdot= minus

Hz nT

V10

2

922

0 DnUπ

Air-cored coil output voltage U0 at a magnetic field x frequency product

1 nT middot Hz versus diameter D with number of turns n as parameter

4

22 dDnWW

sdotsdotsdotsdot=

γπ Weight of coil

Coil resistance2

4

d

nDRDC

ρ=

Thermal voltage noisefTRU DCBN ∆= κ4

W

4W

DnfTU BN

sdotsdotsdotsdot∆=

πγρκ

fHnDdTk

DfHW

TkU

UNS

BBN

sdotsdotsdot

=sdotsdotsdot

== 21302

w00 )(28242

σmicroπ

γρmicroπ

Noise voltage

1028

ln286 9minussdot

+minus= αd

DDL

Equivalent circuit diagram of an air-cored induction coil

For single turn loop Dgtgtd

Long single layer solenoid

[H] 10 H][ 10 922

9222

minusminus sdotsdotsdot

=sdotsdotsdot

asympwd

nD

w

nDL

ππ

622

10 101 46

minussdot+sdot

asympwD

nDL

922

10 10 9 3

778 minussdot++sdot

asymphwD

nDL

Short single layer solenoid wgt16D

Multi-layer solenoid Dgtgtwh

( ) 1

370

ndc

DwC r

sdotminussdotsdotsdot

=ε

1

i

2tot minus+=k

C

k

CC

Capacitance C of a coil

Capacitance C of a single-layer coil normalized to

its diameter D versus length-to-diameter ratio wD

of the coil (capacitance C in pF and geometrical

dimensions w and D in cm)

12 minuskk

High permeability core induction coil

Magnetic field pattern around high permeability core

when it is inserted into a homogeneous field It is valid

for low frequencies and if the coil indicated at the middle

of the core is without current

Magnetization of a high permeability core

dt

dnu ci

i Φ

sdotminus= ) ( cosmaxc ci tωsdotΦ=Φ

ci0rc0 maxAHnnU sdotsdotsdotsdot=Φsdotsdot= micromicroωω

HNHHHH )1( minusminus=+= micro

HN

H sdotminus+

=)1(1

1

r

i micro

irdmi HNHHHH )1( minusminus=+= micro

HfAnU sdotsdotsdotsdotsdotsdot= 0cc0 2 micromicroπ

)1(1 r

rc minus+=

micromicro

microN

minus++

minusminus=

infin1)1ln(

11

1 2

22ell mmm

m

mN

10326) (1ln 152

10156) (1ln 262

ell

cyl

++++

=infin

infin

N

N

Induction coil on a cylindrical high permeability core

Demagnetization factorDemagnetization factorN of prolate ellipsoidsand cylindrical rods(descending curves) andcore permeability μc

(ascending curves) ofcylindrical rods versusthe length-to-diameterratio m of the rod withmaterial permeability μr

as parameter

Core permeability μc of cylindrical rods versus thematerial permeability μr with length-to-diameter ratiom of the rod as parameter after

Minimum noise equivalent magnetic field spectral density of an induction coil sensor with high permeability core versus sensor weight Ws (at length-to-diameter ratios m = 50 and 100 permeability μr = 10000 of the core material and f = 1 Hz)

Induction coil sensors with electronic amplifier

II

rKLC

1=ω

II

II

RR

RK

+=

rr

2 i 1

)(

ωω

ωω

ω

D

KF

+

minus

=

+=

II

II

II

2

C

L

R

R

C

L

KD

Frequency responses of the search coil

Frequency responses of thesensitivity SA and the output voltage UA

of an induction coil sensor with a voltageamplifier at a constant magnetic fieldamplitude

Resonance step-up of thesensitivity SA at differentvalues of the damping D

Sensor with transformer coupled negative feedback to the coil

)(i)()(F

0 ωωωω FR

UMUAU A

A sdot

minus=

)( i1

)(

F

0

ωω

ω

FR

MA

FAUU A

sdot+

sdot=

Induction coil connected to a voltage amplifier with

transformer coupled negative feedback to the coil

FR

21

1K0

i1

1

i1

i )(

ωωωωωω

ωω

+sdot

+sdot=

M

RUU A

IIF2 CRL

MAf

sdotsdotsdotsdot

=∆π

Frequency response of the output voltage UA of an induction coil sensor with negative feedback transformer coupled to the coil

Applications of search coil magnetometer

Developed search coil magnetometer using amorphous ribbon

Experimental setup for the effective permeability measurement

Relative permeability depending on the numbers of ribbon(a)

and the air gap between ribbons

Relative permeability depending on the number of ribbons for the different air gap between ribbons

Relative permeability depending on the total number of ribbons for the different air gap between ribbons

10 pT

100 pT

1 pT

Noise spectrum of the developed search coil magnetometer

BJne

E xH

1minus=

neRH

1minus=

22 nP micromicro minus

Hall 효과

Bt

IRU H

HL =

2

22

)( he

eh

Hpne

nPR

micromicromicromicro

+

minus=

Rectangular Hall plate (cc1cc2 current constant sc1sc2

sensor constant I bias current U voltage drop UH Hall

voltage

Physics carrier concentration and kind of carrier measurement

Engineering magnetic field measurement

Current Measurement

Arrangement for noninvasive

current measurement using an iron

core The current to be measured

produces a proportional magnetic

field which can be measured in the

air gap

Characteristic curve produced by

the current

Arrangement for indirect noninvasive

current measurement using the

compensation principle An iron core as

represented in Figure 3-29 is held field

free by injection a current into a

compensating coil wound on the core

which offsets the field generated by the

current being measured The Hall effect

sensor in the air gap serves as a null

indicator

Circuit diagram for AC-power

measurement using a Hall effect

sensor

DC Power Measurement

Circuit diagram for DC-

power measurement using a

Hall effect sensor

Noncontact Position Sensing

Galvanomagnetic components for sensing the position of permanent magnets

and magnetically conductive materials

Current Sensor Based on Hall Sensor

and Magnetic Core for Hybrid Vehicle

KH Yeon1 SD Kim1 and D Son2 1Auto industry co14F Hanshin IT tower Guro Gu Seoul Korea2Hannam UniversityOjung dong 133 Daejeon Rep of Korea

i

Hall sensor

B

I

SB

ring core

B

I10

g

N

Bl S

micro

)( gtgtrmicro

gab core

Current Sensor Based on Hall

Sensor and Magnetic Core

Hall

Effect

Device

CurrentVoltage

applying for

Hall effect device

operation

Output

signals

Magnetic field

Occurred by

current measurement

Signal

process

circuits

Developed Current Sensor

Magnetic core

Hall sensor

PCB

25

30

35

40

45

50

Output voltage V

Current sensor(Open loop type)

Temp 25C

400A model

+400 ~ -400A

SD 000128

Linearity 003

Linearity of the sensor

Characteristics of the Current Sensors

1000A 10 V power supply

-500 -400 -300 -200 -100 0 100 200 300 400 500

00

05

10

15

20

Output voltage V

current A

Temperature 25Linearity 003

Measuring range -400A ~ +400A

1000A Electronic Load

-3

0

3

6

9

12

15

18

dB

Current sensor

DV2 PCB 24pF

40Aturns

Frequency bandwidth

Gain bandwidth 3 MHz

Current 10 A

Temperature 25

Frequency bandwidth 100 kHz

Sensor output voltage vs frequency

at applied current of 40 Aturns

1 10 100

-18

-15

-12

-9

-6

Frequency kHz 측정온도 25

주파수특성 30kHz 이상(3dB 기준)

측정전류 40Aturns(4A 10턴)

측정주파수 100Hz ~ 100kHz

Temperature 25Current 40Aturns

Frequency range 100 Hz ~ 100 kHz

What is Magnetoresistance

Magnetoresistance effect(AMR)

θθθ 2cos2

12sin12cos(

22 minusminus+∆asymp∆ xxxmx hhhRR

32 minusasymp∆ ρρ New effect GMR CMR and GMI

10 ge∆ ρρ

Two bridge configuration for

rotational angle measurement

measurement angle more than 180o

자동차 Engine Management System

Inductive and Eddy Current

Sensors Excited by Permanent Magnets

tNtU dd)( φsdotminus=

construction of an inductive

sensor (courtesy VDO Adolf sensor (courtesy VDO Adolf

Schindling AG)

1) constant socket

2) terminal package

3) permanent magnet

4) cap

5) soft magnetic core

6) coil

7) plate

8) blade connector

γγ

Sensor with yoke Change in the magnetic flux with

varying air gap Continuous lines

minimum air gap dashed lines

maximum air gap

C-shaped sensor

Sensor with radially

magnetized

permanent magnet

Signal Conditioning

Output voltage U of a DC-excited sensor with permanent

magnets when a single iron object passes by

Schematic electrical diagram of an inductive sensor

Linear Variable Differential Transformer

AC-Excited Sensors for Linear Movement

Principle of construction of an LVDT

Electrical circuit of an LVDT

tIMtNU dd dd sdotminus=sdotminus= φ

tIMtIMUUU dd dd 1212 sdotminussdot=minus=

tIMMU dd)( 12 sdotminus=

)(12 xMMMM =minus=

tIxMU dd)( sdot= tI

UxM

dd)( =

Signal Conditioning

power supply

carrier gen

autoampcontrol

LVDTcarrieramp

demod-ulator

phase

shifter

power supply

carrier gen

passivedemod-ulator

LVDTDCamp

Block diagram of a carrier amplifier system

Block diagram of a DC amplifier system

Variable Inductive Sensors

Principle of construction

of the VLP sensor

Principle of a bridge

circuit

lANL r 20 sdotsdotsdot= micromicro

21 BA UUU minus=

21)i(ii( 211 minus+sdot= LLLUU BA ωωω

)21))()((( minus∆minus+∆+∆+sdot= LLLLLLUU BA

)212)(( minus∆+sdot= LLLUU )212)(( minus∆+sdot= LLLUU BA

LLUU BA 21 ∆sdotsdot=

llLL ∆sdot=∆ d d

llLLUU BA ∆sdotsdot= d d)2(1

Applications and Properties

Principle of a construction of a force transducer

(courtesy Hottinger Baldwin Messtechnik)

Vibrationacceleration sensor

Signal Conditioning

Schematic electrical diagram of a force transducer connected with an

amplifier (courtesy Hottinger Baldwin Messtechnik GmbH)

Variable Gap Sensors

)( FeFe2

0 LLllANL micromicromicro +sdotsdot=

FeFe2

0max lANL sdotsdotsdot= micromicro

Construction of a variable gap sensor

Characteristic of a variable gap sensor

Construction of a differential

cross-anchor sensor

Output voltage U versus core

position x plusmn a limits of the

linear rage

Applications of differential cross-anchor sensors

AC-excited Sensors for Rotary Movements

Principle of construction of a synchro

α cos10 sdotsdot= UKU y

)120-( cos10 degsdotsdot= αUKU z

)240-( cos10 degsdotsdot= αUKU x

)120-( sin3100 degsdotsdotsdot=minus= αKUUUU yxyx

)240-( sin3100 degsdotsdotsdot=minus= αKUUUU zyzy

α sin3100 sdotsdotsdot=minus= KUUUU xzxz

Application to the Torque Sensor

Principle of construction of a torque-type synchro

Torque versus angular

difference

)( sin~ rt αα minussdotKM

)( cos~ rt1r αα minussdotUU

Principle of construction of a control-type sensor

Output voltage versus

angular difference

Principle of construction of a differential sychro

Eddy Current Sensors

tBE dd curl minus=JH = curl

0 div =BH(H)B sdot= micro

E(E)J sdot= σ

A B curl= A B curl=

tdd- A E =

)dd( tAJ minus= σ

tdd curl curl AA σmicro minus=

AA) σωmicro iminus= curl )(curl(1

AA) σωmicro i=∆)((1

Eddy Current Tachometer

Construction of a speedometer (courtesy VDO Adolf Schinding AG) 1) spindle 2) bearing

3) holding spring 4) iron yoke 5) eddy current cup 6) shaft of the magnet 7) support of

the magnet 8) temperature compensation 9) permanent magnet 10) torsion spring

Proximity Sensors

Schematic diagram of a proximity sensor

Output current of a proximity switch versus distance

Inductive Flowmeters

)( Btimessdot= υqF

EqF sdot=BE times=υ

)(ds Btimes== υEU )(ds Btimes== υEU

)( Bd timessdot= υU

Bsdotsdotsdot= υdKU

Development of magnetic phase detection

sensor for steam generator tube

Dirac Son1 Kwan-Sang Ryu2 Duck-Gun Park3

1Hannam University Daejeon Rep of Korea2Korea Research Institute of Standards and Science Daejeon Rep of Korea3KoreaAtomic Energy Research Institute Daejeon Rep of Korea

Introduction

The layout of pressurized water reactor (PWR) components

Primary side Secondary side (non-radioactive side)(radioactive side)

The Structure of SG(Steam Generator)(degradation mechanism)

Secondary SidePrimary Side

SCC

A B

A-B

Steam outlet

Anti-vibration

SCC

Fretting

Wall thinning

IGA

U-bend

In commercial power plants SG- height up to 21 m - weight up to 800 tons - 2~4 sets of SG were installed - SG can contain from 3000 to

16000 tubes each about 20 mmin diameter

Primary coolant outlet Primary coolant inlet

Anti-vibrationbars

Tubesupportplate

Tubesheet

IGA

SCC

Pitting

SCC

Inside Tubesheet

Top of Tubesheet

by SSHwang of KAERI

Denting

Sludge pile

in diameter

The SGT is made of nickel basedInconel alloy which is composed of 75 Ni 165Cr and 815Fe

-Degradation mechanism corrosion pitting denting inter granular attack

-Inspection Eddy current Testing(ECT)

Permeability Variation Clusters (PVC)

(Ferro-magnetic phase)

-005

000

005

010

015

m (emug)

1-1

-002

000

002

004

006

008

m (emug)

1-2

-1000 -500 0 500 1000

-015

-010

-005

H ( Am )

-1000 -500 0 500 1000

-006

-004

-002

H ( Am )

The hystresis loop in the fragment of PVC parts of Kori-1 retired SG tube

-004

-002

000

002

004

006

M (emug)

Inconel 600 tested at RT

under tensile stress

1 2 3

4 5 6

7 8 9-004

-002

000

002

004

006

M(emug)

Inconel 600 Heat treated at

602 oC under tensile stress

1 2 3

How can we detect magnetic phase

(PVC)selectively from the flaws in SGT

-3000 -2000 -1000 0 1000 2000 3000

-006

H (Oe)

7 8 9

10 11 12

-3000 -2000 -1000 0 1000 2000 3000

-006

-004

H(Oe)

4 5 6

7 8 9

The hysteresis loop of the tensile tested specimen at room temperature (a) and tensile tested at high temperature (b)

The magnetic phase can be created under the high temperature andpressure conditions which is correspond to the stress corrosion crackingin the SG tube in the NPP(Bruemmer SM Charlot LA amp Henager CH (1988) Corrosion 782)

Principle of ECT

If we can separate magnetic phase selectively from the

flaws using magnetic sensor the reliability of EC in SGT

inspection will be greatly enhanced

Structure of the permeability

sensor

Dimension and photograph of U-shape

sensing yoke

Design of Magnetic Sensor for PVC

sensor sensing yoke

Photograph of the completed sensor front side (above) and rear side (bottom)

R11R12

R10

R8

R6

R9

R13

R7

R14

C18

1 n

C17

C20

C21

D2

DIODE

SIN COS

-

+

U-2A

4

13

2

-

+

U-2B

75

6

8

-

+

U-3A

13

2

8

+5VC19

104

+5V

Schematic diagram of the sensor system

Electronic Circuit of Magnetic Sensor

R20

R

R21

R

-

+

U5AD797

3

26

74

U6

D1

S12

GND3

+VCC4VCC5

IN6

-VCC7

S28

C41

R13

R26

R18

R25

R2210 Ω

R16

R14

R17

10 k

R15

R27

R32

R28

R33

R29

R34

5 k

R30

C29

C37

104

C32473

C39473C40

104

C33

104

C21

104C23

104

C25

104

C26

104

C30

104

C31

104

C35

104

C36

104

C27

104

C28

104

C34

104

C38

104

D3

DIODE

L1

1

2

L2

1

2

L3

1

2

4

-

+

U-4A

4

13

2

-

+

U-4B

75

6

8

-

+

U-5A

4

13

2

-

+

U-5B

75

6

8

-

+

U-6A

4

13

2

-

+

U-6B

75

6

8

C22

104

-5V

+5V

+5V

+5V

+5V

+5V

+5V

U7

D1

S12

GND3

+VCC4

VCC5

IN6

-VCC7

S28

+5V

-5V

-5V

-5V

-5V

-5V

-5V

-5V

-5V

R19

R24

R

R23

R

C24

OUT(X)

OUT(Y)

R1

20 kR210 k

R3

20 kR410 k

C1

104

C8

104

REF43

OUT(X)

OUT(Y)

REF43

U2

+Vcc1

CH02

CH13

CH24

CH35

COMM6

SHDN7

Vref8

+Vcc9

GND10

GND11

DOUT12BUSY13DIN14CS15

DIN16

-

+

U-1A

13

2

8

-

+

U-1B

4

75

6

C410 uF

C5104

DOUT

C210uF

C6104

C3104

DCLK

C7104

DIN

C10

01uF

CS

BUSY

C14 10uF

J1

CON6

123456

D1

DIODE

R5

47K

C9

10uF

C1310uF

Y1

OSC

OUT3

GND2

VCC4

U3

RSTVPP1

GND10

VCC20

XTAL15

XTAL24

P10AIN012P11AIN113P1214P1315P1416P1517P1618P1719

P30RXD2

P31TXD3

P32INT06

P33INT17

P34T08

P35T19

P3711

U4

C1+1

C1-3

C2+4

C2-5

VCC16

GND15

V+2

V-6

R1OUT12

R2OUT9

T1IN11

T2IN10

R1IN13

R2IN8

T1OUT14

T2OUT7

C12 10uF

C16

01uF

C15 10uF

C11

01uF

-5V

+5V

+5V

+5V

+5V

+5V

+5V

+5V

RST

OSC

OSC

RST

DCLKCSDINBUSYDOUT

U1

IN2

GND

4

OUT6

TEMP3

TRIM5

-5V

+5V

Electronic circuit diagram of the magnetic sensor

Photograph of the completed measuring system data acquisition

software in PC and probe scanning system

Experimental Setup for Magnetic Sensor

Reference material Scanning System Software LabVIEW

Reference Material (1) Normal defects and PVCs

Longitudinal and transverse defects

Def W L D Remarks

1 02 500 0213 (20 ) Inner defects

2 02 500 0427 (40 )

3 02 500 0213 (20 )Outer defectsPVC(1018)4 02 500 0427 (40 )

5 02 500 0639 (60 )

6 02 500 0852 (80 )

7 02 500 0639 (60 ) Inner defects

8 02 500 0852 (80 )

- 1 and 2 are inner defects

- 345 and 6 are outer defects with PVC

- 7 and 8 are inner defects

PVC

PVC

Defect Defect

For longitudinal defects and PVC For circumferential defects and PVC

ECT is very difficult to detect circumferential defects

We can distinguish PVCs and defects and longitudinal and circumferential defects

Flux-gate Magnetometer

One core sensor Two core sensor

3-축 flux-gate Magnetometer의 계략도

Sensorpia Co

pro

cess

or(

AV

R)

Sensor 1

RS422

Interface

Mic

ro-p

roce

ssor(

AV

R)

Sensor 2

Sensor 3

Interface

조립된 마그네토미터의 사진

Sensorpia Co

Analog PCB

Digital PCB

Sensorpia Co선형도(linearity)

10

20

30

40

50

60

y-axis

Magnetometer Output (microT)

-60 -50 -40 -30 -20 -10 0 10 20 30 40 50 60

-60

-50

-40

-30

-20

-10

0

10

Y-axis y=099946 x+0015STD 106E-4

Magnetometer Output (

Applied Magnetic Field (microT)

마그네토미터의 noise 특성 Sensorpia Co

1

10

100

y-axis

Magnetometer noise (nT)

0 1 2 3 4 5 6

1E-4

1E-3

001

01

Magnetometer noise (nT)

Frequency (Hz)

Magnetometer for KoDSAT

-150 -100 -50 0 50 100 150

-15

-10

-5

0

5

10

15

Magnetic Moment (Am

2)

Current (mA)

After Thermal Cycle Test

Measured

Resistance 193 ohm

Photograph of Magnetic torquer

Photograph of KoDSAT

Photograph of

3-axis Fluxgate

Magnetometer

Photograph of Magnetic torquer

Application of magnetometer

Moon magnetic fieldmeasurement

Telescope with direction indication

Joule Effect (Magnetostriction)

ϕ2cosel

l=

∆

0=∆

+∆

+∆

b

b

a

a

l

l

Actuator using Terfenol-D

00

05

10

B (T)

800

1000

1200

1400

1600

Magnetostriction (ppm)

-100 -50 0 50 100

-10

-05

00

B (T)

H (kAm)

2 MPa

4 MPa

6 MPa

8 MPa

10 MPa

12 MPa

-100 -50 0 50 100

-200

0

200

400

600

Magnetostriction (ppm)

H (kAm)

2 MPa

4 MPa

6 MPa

8 MPa

10 MPa

12 MPa

600

700

800

900

1000

-4 -3 -2 -1 0 1 2 3 4

0

10

20

30

40

50

60

Displacement (m

icro meter)

I (A)

FIELD

9 kAm

12 kAm

16 kAm

20 kAm

24 kAm

38 kAm

-50 -40 -30 -20 -10 0 10 20 30 40 50

-100

0

100

200

300

400

500

L (PPM)

H (kAm)

9 kAm

12 kAm

16 kAm

20 kAm

24 kAm

38 kAm

Magnetostrictive displacement sensor

Hysteresis loops under

tensile stress σ

(a) Crystalline 68 NiFe

λs = +25 10-6

(b) crystalline pure Ni λs

= -35 10-6

Villari Effect ( Inverse of Joule Effect)

= -35 10-6

(c) amorphous Co-based

alloy

λs = -35 10-6

ϕσλ 2sin2

3sdotsdot= smeE

γ

Permeability depending on the stress

σλmicromicro

1

3

2

Y

J

so

s

r =

γ

Calculated magnetization curves under stress

Variation of magnetization curve by an applied

tensile force (Co-based amorphous alloy)

Alloy Requirement

Materials for magnetoelastic sensors

Why amorphous magnetic materials are important

Stress-strain curves of several materials

Coercivity and hardness of several materials

Principles of magnetoelastic sensors

Non-contact torque sensor

Principle of cross torductor torque

sensor and flux pattern of sensor

poles on the surface of a shaft

a) without and b)with torsional load

Equivalent magnetic circuit of

cross type torque sensor

Helices of principal tensile and compressive stress on the surface of

a shaft subjected to torsion [32] Correlated changes of permeability

are detected by four-branch yoke system with sensing coils 123

and 4 and a common excitation pole

Examples of torque sensors

Four-branch type torque sensor

heads Pole structures realized

by commercial multi-pole

ferrites 14 and 18 min in

diameter (diameter of sensor

h e a d 1 7 a n d 2 4 m m

respectively) respectively)

Principle of Ring Torductor torque transducer

(a b) Physical structure (c) evolution of the

shaft surface under the transducer poles A and BRing torductor for measuring

torque on ship propeller shafts

(shaft diameter ca 500 mm)

(Courtesy ASEA Brown

Boveri AG)

Principal designs of coaxial torque sensors

Schematic diagram of data processing

electronics of a torque sensor

Extensometer (a) Construction of strain sensing element using

amorphous ribbon wound core (b) configuration of lumped

windings

∆E effect of an amorphous FeNi-based

alloy (Fe40 Ni38 Mo4 B18) Hs saturation

field

Magnetically tunable delay line

Torque Sensors using Amorphous wire

Sixtus tonk효과(large Barkhausen효과)

Hysteresis loops of a Wiegand wire for different reset fields

Curie 온도 및Hopkinson효과

Relation between normalised

saturation polarisation and

normalised Curie temperature

Permeability of a Mn-Zn ferrite as

a function of temperature and field

strength

Conclusions

1) Magnetic sensor 는 자동차 공장자동화 항공우주 및 군사용으로많이 사용되고 있다

2) 새로운 소재개발은 자기센서의 성능개발에 직접적인 영향을 준다2) 새로운 소재개발은 자기센서의 성능개발에 직접적인 영향을 준다

3) 센서의 개발을 위해서는 다양한 전공지식이 요구된다

(물리학 재료공학 기계공학 전자공학)

4) 센서분야가 고부가가치를 창출하는 부품사업이다

5) 핵심부품을 생산하는 중소기업의 item으로도 적절하다

Sensitivity and Noise of Air Cored Induction Coil

HfDnHAnnU sdotsdotsdotsdotsdot=sdotsdotsdotsdot=Φsdotsdot= 02

2

0max02

microπ

microωω

2

022

00

microπ sdotsdot=

sdot=

Dn

Hf

US

V2π

sdotsdot=

sdotsdot

sdot= minus2

-970

m Hz nT

V10

m A

S V104πmicro

sdot

sdotsdot= minus

Hz nT

V10

2

922

0 DnUπ

Air-cored induction coil in a time-varying magnetic field

sdot

sdotsdot= minus

Hz nT

V10

2

922

0 DnUπ

Air-cored coil output voltage U0 at a magnetic field x frequency product

1 nT middot Hz versus diameter D with number of turns n as parameter

4

22 dDnWW

sdotsdotsdotsdot=

γπ Weight of coil

Coil resistance2

4

d

nDRDC

ρ=

Thermal voltage noisefTRU DCBN ∆= κ4

W

4W

DnfTU BN

sdotsdotsdotsdot∆=

πγρκ

fHnDdTk

DfHW

TkU

UNS

BBN

sdotsdotsdot

=sdotsdotsdot

== 21302

w00 )(28242

σmicroπ

γρmicroπ

Noise voltage

1028

ln286 9minussdot

+minus= αd

DDL

Equivalent circuit diagram of an air-cored induction coil

For single turn loop Dgtgtd

Long single layer solenoid

[H] 10 H][ 10 922

9222

minusminus sdotsdotsdot

=sdotsdotsdot

asympwd

nD

w

nDL

ππ

622

10 101 46

minussdot+sdot

asympwD

nDL

922

10 10 9 3

778 minussdot++sdot

asymphwD

nDL

Short single layer solenoid wgt16D

Multi-layer solenoid Dgtgtwh

( ) 1

370

ndc

DwC r

sdotminussdotsdotsdot

=ε

1

i

2tot minus+=k

C

k

CC

Capacitance C of a coil

Capacitance C of a single-layer coil normalized to

its diameter D versus length-to-diameter ratio wD

of the coil (capacitance C in pF and geometrical

dimensions w and D in cm)

12 minuskk

High permeability core induction coil

Magnetic field pattern around high permeability core

when it is inserted into a homogeneous field It is valid

for low frequencies and if the coil indicated at the middle

of the core is without current

Magnetization of a high permeability core

dt

dnu ci

i Φ

sdotminus= ) ( cosmaxc ci tωsdotΦ=Φ

ci0rc0 maxAHnnU sdotsdotsdotsdot=Φsdotsdot= micromicroωω

HNHHHH )1( minusminus=+= micro

HN

H sdotminus+

=)1(1

1

r

i micro

irdmi HNHHHH )1( minusminus=+= micro

HfAnU sdotsdotsdotsdotsdotsdot= 0cc0 2 micromicroπ

)1(1 r

rc minus+=

micromicro

microN

minus++

minusminus=

infin1)1ln(

11

1 2

22ell mmm

m

mN

10326) (1ln 152

10156) (1ln 262

ell

cyl

++++

=infin

infin

N

N

Induction coil on a cylindrical high permeability core

Demagnetization factorDemagnetization factorN of prolate ellipsoidsand cylindrical rods(descending curves) andcore permeability μc

(ascending curves) ofcylindrical rods versusthe length-to-diameterratio m of the rod withmaterial permeability μr

as parameter

Core permeability μc of cylindrical rods versus thematerial permeability μr with length-to-diameter ratiom of the rod as parameter after

Minimum noise equivalent magnetic field spectral density of an induction coil sensor with high permeability core versus sensor weight Ws (at length-to-diameter ratios m = 50 and 100 permeability μr = 10000 of the core material and f = 1 Hz)

Induction coil sensors with electronic amplifier

II

rKLC

1=ω

II

II

RR

RK

+=

rr

2 i 1

)(

ωω

ωω

ω

D

KF

+

minus

=

+=

II

II

II

2

C

L

R

R

C

L

KD

Frequency responses of the search coil

Frequency responses of thesensitivity SA and the output voltage UA

of an induction coil sensor with a voltageamplifier at a constant magnetic fieldamplitude

Resonance step-up of thesensitivity SA at differentvalues of the damping D

Sensor with transformer coupled negative feedback to the coil

)(i)()(F

0 ωωωω FR

UMUAU A

A sdot

minus=

)( i1

)(

F

0

ωω

ω

FR

MA

FAUU A

sdot+

sdot=

Induction coil connected to a voltage amplifier with

transformer coupled negative feedback to the coil

FR

21

1K0

i1

1

i1

i )(

ωωωωωω

ωω

+sdot

+sdot=

M

RUU A

IIF2 CRL

MAf

sdotsdotsdotsdot

=∆π

Frequency response of the output voltage UA of an induction coil sensor with negative feedback transformer coupled to the coil

Applications of search coil magnetometer

Developed search coil magnetometer using amorphous ribbon

Experimental setup for the effective permeability measurement

Relative permeability depending on the numbers of ribbon(a)

and the air gap between ribbons

Relative permeability depending on the number of ribbons for the different air gap between ribbons

Relative permeability depending on the total number of ribbons for the different air gap between ribbons

10 pT

100 pT

1 pT

Noise spectrum of the developed search coil magnetometer

BJne

E xH

1minus=

neRH

1minus=

22 nP micromicro minus

Hall 효과

Bt

IRU H

HL =

2

22

)( he

eh

Hpne

nPR

micromicromicromicro

+

minus=

Rectangular Hall plate (cc1cc2 current constant sc1sc2

sensor constant I bias current U voltage drop UH Hall

voltage

Physics carrier concentration and kind of carrier measurement

Engineering magnetic field measurement

Current Measurement

Arrangement for noninvasive

current measurement using an iron

core The current to be measured

produces a proportional magnetic

field which can be measured in the

air gap

Characteristic curve produced by

the current

Arrangement for indirect noninvasive

current measurement using the

compensation principle An iron core as

represented in Figure 3-29 is held field

free by injection a current into a

compensating coil wound on the core

which offsets the field generated by the

current being measured The Hall effect

sensor in the air gap serves as a null

indicator

Circuit diagram for AC-power

measurement using a Hall effect

sensor

DC Power Measurement

Circuit diagram for DC-

power measurement using a

Hall effect sensor

Noncontact Position Sensing

Galvanomagnetic components for sensing the position of permanent magnets

and magnetically conductive materials

Current Sensor Based on Hall Sensor

and Magnetic Core for Hybrid Vehicle

KH Yeon1 SD Kim1 and D Son2 1Auto industry co14F Hanshin IT tower Guro Gu Seoul Korea2Hannam UniversityOjung dong 133 Daejeon Rep of Korea

i

Hall sensor

B

I

SB

ring core

B

I10

g

N

Bl S

micro

)( gtgtrmicro

gab core

Current Sensor Based on Hall

Sensor and Magnetic Core

Hall

Effect

Device

CurrentVoltage

applying for

Hall effect device

operation

Output

signals

Magnetic field

Occurred by

current measurement

Signal

process

circuits

Developed Current Sensor

Magnetic core

Hall sensor

PCB

25

30

35

40

45

50

Output voltage V

Current sensor(Open loop type)

Temp 25C

400A model

+400 ~ -400A

SD 000128

Linearity 003

Linearity of the sensor

Characteristics of the Current Sensors

1000A 10 V power supply

-500 -400 -300 -200 -100 0 100 200 300 400 500

00

05

10

15

20

Output voltage V

current A

Temperature 25Linearity 003

Measuring range -400A ~ +400A

1000A Electronic Load

-3

0

3

6

9

12

15

18

dB

Current sensor

DV2 PCB 24pF

40Aturns

Frequency bandwidth

Gain bandwidth 3 MHz

Current 10 A

Temperature 25

Frequency bandwidth 100 kHz

Sensor output voltage vs frequency

at applied current of 40 Aturns

1 10 100

-18

-15

-12

-9

-6

Frequency kHz 측정온도 25

주파수특성 30kHz 이상(3dB 기준)

측정전류 40Aturns(4A 10턴)

측정주파수 100Hz ~ 100kHz

Temperature 25Current 40Aturns

Frequency range 100 Hz ~ 100 kHz

What is Magnetoresistance

Magnetoresistance effect(AMR)

θθθ 2cos2

12sin12cos(

22 minusminus+∆asymp∆ xxxmx hhhRR

32 minusasymp∆ ρρ New effect GMR CMR and GMI

10 ge∆ ρρ

Two bridge configuration for

rotational angle measurement

measurement angle more than 180o

자동차 Engine Management System

Inductive and Eddy Current

Sensors Excited by Permanent Magnets

tNtU dd)( φsdotminus=

construction of an inductive

sensor (courtesy VDO Adolf sensor (courtesy VDO Adolf

Schindling AG)

1) constant socket

2) terminal package

3) permanent magnet

4) cap

5) soft magnetic core

6) coil

7) plate

8) blade connector

γγ

Sensor with yoke Change in the magnetic flux with

varying air gap Continuous lines

minimum air gap dashed lines

maximum air gap

C-shaped sensor

Sensor with radially

magnetized

permanent magnet

Signal Conditioning

Output voltage U of a DC-excited sensor with permanent

magnets when a single iron object passes by

Schematic electrical diagram of an inductive sensor

Linear Variable Differential Transformer

AC-Excited Sensors for Linear Movement

Principle of construction of an LVDT

Electrical circuit of an LVDT

tIMtNU dd dd sdotminus=sdotminus= φ

tIMtIMUUU dd dd 1212 sdotminussdot=minus=

tIMMU dd)( 12 sdotminus=

)(12 xMMMM =minus=

tIxMU dd)( sdot= tI

UxM

dd)( =

Signal Conditioning

power supply

carrier gen

autoampcontrol

LVDTcarrieramp

demod-ulator

phase

shifter

power supply

carrier gen

passivedemod-ulator

LVDTDCamp

Block diagram of a carrier amplifier system

Block diagram of a DC amplifier system

Variable Inductive Sensors

Principle of construction

of the VLP sensor

Principle of a bridge

circuit

lANL r 20 sdotsdotsdot= micromicro

21 BA UUU minus=

21)i(ii( 211 minus+sdot= LLLUU BA ωωω

)21))()((( minus∆minus+∆+∆+sdot= LLLLLLUU BA

)212)(( minus∆+sdot= LLLUU )212)(( minus∆+sdot= LLLUU BA

LLUU BA 21 ∆sdotsdot=

llLL ∆sdot=∆ d d

llLLUU BA ∆sdotsdot= d d)2(1

Applications and Properties

Principle of a construction of a force transducer

(courtesy Hottinger Baldwin Messtechnik)

Vibrationacceleration sensor

Signal Conditioning

Schematic electrical diagram of a force transducer connected with an

amplifier (courtesy Hottinger Baldwin Messtechnik GmbH)

Variable Gap Sensors

)( FeFe2

0 LLllANL micromicromicro +sdotsdot=

FeFe2

0max lANL sdotsdotsdot= micromicro

Construction of a variable gap sensor

Characteristic of a variable gap sensor

Construction of a differential

cross-anchor sensor

Output voltage U versus core

position x plusmn a limits of the

linear rage

Applications of differential cross-anchor sensors

AC-excited Sensors for Rotary Movements

Principle of construction of a synchro

α cos10 sdotsdot= UKU y

)120-( cos10 degsdotsdot= αUKU z

)240-( cos10 degsdotsdot= αUKU x

)120-( sin3100 degsdotsdotsdot=minus= αKUUUU yxyx

)240-( sin3100 degsdotsdotsdot=minus= αKUUUU zyzy

α sin3100 sdotsdotsdot=minus= KUUUU xzxz

Application to the Torque Sensor

Principle of construction of a torque-type synchro

Torque versus angular

difference

)( sin~ rt αα minussdotKM

)( cos~ rt1r αα minussdotUU

Principle of construction of a control-type sensor

Output voltage versus

angular difference

Principle of construction of a differential sychro

Eddy Current Sensors

tBE dd curl minus=JH = curl

0 div =BH(H)B sdot= micro

E(E)J sdot= σ

A B curl= A B curl=

tdd- A E =

)dd( tAJ minus= σ

tdd curl curl AA σmicro minus=

AA) σωmicro iminus= curl )(curl(1

AA) σωmicro i=∆)((1

Eddy Current Tachometer

Construction of a speedometer (courtesy VDO Adolf Schinding AG) 1) spindle 2) bearing

3) holding spring 4) iron yoke 5) eddy current cup 6) shaft of the magnet 7) support of

the magnet 8) temperature compensation 9) permanent magnet 10) torsion spring

Proximity Sensors

Schematic diagram of a proximity sensor

Output current of a proximity switch versus distance

Inductive Flowmeters

)( Btimessdot= υqF

EqF sdot=BE times=υ

)(ds Btimes== υEU )(ds Btimes== υEU

)( Bd timessdot= υU

Bsdotsdotsdot= υdKU

Development of magnetic phase detection

sensor for steam generator tube

Dirac Son1 Kwan-Sang Ryu2 Duck-Gun Park3

1Hannam University Daejeon Rep of Korea2Korea Research Institute of Standards and Science Daejeon Rep of Korea3KoreaAtomic Energy Research Institute Daejeon Rep of Korea

Introduction

The layout of pressurized water reactor (PWR) components

Primary side Secondary side (non-radioactive side)(radioactive side)

The Structure of SG(Steam Generator)(degradation mechanism)

Secondary SidePrimary Side

SCC

A B

A-B

Steam outlet

Anti-vibration

SCC

Fretting

Wall thinning

IGA

U-bend

In commercial power plants SG- height up to 21 m - weight up to 800 tons - 2~4 sets of SG were installed - SG can contain from 3000 to

16000 tubes each about 20 mmin diameter

Primary coolant outlet Primary coolant inlet

Anti-vibrationbars

Tubesupportplate

Tubesheet

IGA

SCC

Pitting

SCC

Inside Tubesheet

Top of Tubesheet

by SSHwang of KAERI

Denting

Sludge pile

in diameter

The SGT is made of nickel basedInconel alloy which is composed of 75 Ni 165Cr and 815Fe

-Degradation mechanism corrosion pitting denting inter granular attack

-Inspection Eddy current Testing(ECT)

Permeability Variation Clusters (PVC)

(Ferro-magnetic phase)

-005

000

005

010

015

m (emug)

1-1

-002

000

002

004

006

008

m (emug)

1-2

-1000 -500 0 500 1000

-015

-010

-005

H ( Am )

-1000 -500 0 500 1000

-006

-004

-002

H ( Am )

The hystresis loop in the fragment of PVC parts of Kori-1 retired SG tube

-004

-002

000

002

004

006

M (emug)

Inconel 600 tested at RT

under tensile stress

1 2 3

4 5 6

7 8 9-004

-002

000

002

004

006

M(emug)

Inconel 600 Heat treated at

602 oC under tensile stress

1 2 3

How can we detect magnetic phase

(PVC)selectively from the flaws in SGT

-3000 -2000 -1000 0 1000 2000 3000

-006

H (Oe)

7 8 9

10 11 12

-3000 -2000 -1000 0 1000 2000 3000

-006

-004

H(Oe)

4 5 6

7 8 9

The hysteresis loop of the tensile tested specimen at room temperature (a) and tensile tested at high temperature (b)

The magnetic phase can be created under the high temperature andpressure conditions which is correspond to the stress corrosion crackingin the SG tube in the NPP(Bruemmer SM Charlot LA amp Henager CH (1988) Corrosion 782)

Principle of ECT

If we can separate magnetic phase selectively from the

flaws using magnetic sensor the reliability of EC in SGT

inspection will be greatly enhanced

Structure of the permeability

sensor

Dimension and photograph of U-shape

sensing yoke

Design of Magnetic Sensor for PVC

sensor sensing yoke

Photograph of the completed sensor front side (above) and rear side (bottom)

R11R12

R10

R8

R6

R9

R13

R7

R14

C18

1 n

C17

C20

C21

D2

DIODE

SIN COS

-

+

U-2A

4

13

2

-

+

U-2B

75

6

8

-

+

U-3A

13

2

8

+5VC19

104

+5V

Schematic diagram of the sensor system

Electronic Circuit of Magnetic Sensor

R20

R

R21

R

-

+

U5AD797

3

26

74

U6

D1

S12

GND3

+VCC4VCC5

IN6

-VCC7

S28

C41

R13

R26

R18

R25

R2210 Ω

R16

R14

R17

10 k

R15

R27

R32

R28

R33

R29

R34

5 k

R30

C29

C37

104

C32473

C39473C40

104

C33

104

C21

104C23

104

C25

104

C26

104

C30

104

C31

104

C35

104

C36

104

C27

104

C28

104

C34

104

C38

104

D3

DIODE

L1

1

2

L2

1

2

L3

1

2

4

-

+

U-4A

4

13

2

-

+

U-4B

75

6

8

-

+

U-5A

4

13

2

-

+

U-5B

75

6

8

-

+

U-6A

4

13

2

-

+

U-6B

75

6

8

C22

104

-5V

+5V

+5V

+5V

+5V

+5V

+5V

U7

D1

S12

GND3

+VCC4

VCC5

IN6

-VCC7

S28

+5V

-5V

-5V

-5V

-5V

-5V

-5V

-5V

-5V

R19

R24

R

R23

R

C24

OUT(X)

OUT(Y)

R1

20 kR210 k

R3

20 kR410 k

C1

104

C8

104

REF43

OUT(X)

OUT(Y)

REF43

U2

+Vcc1

CH02

CH13

CH24

CH35

COMM6

SHDN7

Vref8

+Vcc9

GND10

GND11

DOUT12BUSY13DIN14CS15

DIN16

-

+

U-1A

13

2

8

-

+

U-1B

4

75

6

C410 uF

C5104

DOUT

C210uF

C6104

C3104

DCLK

C7104

DIN

C10

01uF

CS

BUSY

C14 10uF

J1

CON6

123456

D1

DIODE

R5

47K

C9

10uF

C1310uF

Y1

OSC

OUT3

GND2

VCC4

U3

RSTVPP1

GND10

VCC20

XTAL15

XTAL24

P10AIN012P11AIN113P1214P1315P1416P1517P1618P1719

P30RXD2

P31TXD3

P32INT06

P33INT17

P34T08

P35T19

P3711

U4

C1+1

C1-3

C2+4

C2-5

VCC16

GND15

V+2

V-6

R1OUT12

R2OUT9

T1IN11

T2IN10

R1IN13

R2IN8

T1OUT14

T2OUT7

C12 10uF

C16

01uF

C15 10uF

C11

01uF

-5V

+5V

+5V

+5V

+5V

+5V

+5V

+5V

RST

OSC

OSC

RST

DCLKCSDINBUSYDOUT

U1

IN2

GND

4

OUT6

TEMP3

TRIM5

-5V

+5V

Electronic circuit diagram of the magnetic sensor

Photograph of the completed measuring system data acquisition

software in PC and probe scanning system

Experimental Setup for Magnetic Sensor

Reference material Scanning System Software LabVIEW

Reference Material (1) Normal defects and PVCs

Longitudinal and transverse defects

Def W L D Remarks

1 02 500 0213 (20 ) Inner defects

2 02 500 0427 (40 )

3 02 500 0213 (20 )Outer defectsPVC(1018)4 02 500 0427 (40 )

5 02 500 0639 (60 )

6 02 500 0852 (80 )

7 02 500 0639 (60 ) Inner defects

8 02 500 0852 (80 )

- 1 and 2 are inner defects

- 345 and 6 are outer defects with PVC

- 7 and 8 are inner defects

PVC

PVC

Defect Defect

For longitudinal defects and PVC For circumferential defects and PVC

ECT is very difficult to detect circumferential defects

We can distinguish PVCs and defects and longitudinal and circumferential defects

Flux-gate Magnetometer

One core sensor Two core sensor

3-축 flux-gate Magnetometer의 계략도

Sensorpia Co

pro

cess

or(

AV

R)

Sensor 1

RS422

Interface

Mic

ro-p

roce

ssor(

AV

R)

Sensor 2

Sensor 3

Interface

조립된 마그네토미터의 사진

Sensorpia Co

Analog PCB

Digital PCB

Sensorpia Co선형도(linearity)

10

20

30

40

50

60

y-axis

Magnetometer Output (microT)

-60 -50 -40 -30 -20 -10 0 10 20 30 40 50 60

-60

-50

-40

-30

-20

-10

0

10

Y-axis y=099946 x+0015STD 106E-4

Magnetometer Output (

Applied Magnetic Field (microT)

마그네토미터의 noise 특성 Sensorpia Co

1

10

100

y-axis

Magnetometer noise (nT)

0 1 2 3 4 5 6

1E-4

1E-3

001

01

Magnetometer noise (nT)

Frequency (Hz)

Magnetometer for KoDSAT

-150 -100 -50 0 50 100 150

-15

-10

-5

0

5

10

15

Magnetic Moment (Am

2)

Current (mA)

After Thermal Cycle Test

Measured

Resistance 193 ohm

Photograph of Magnetic torquer

Photograph of KoDSAT

Photograph of

3-axis Fluxgate

Magnetometer

Photograph of Magnetic torquer

Application of magnetometer

Moon magnetic fieldmeasurement

Telescope with direction indication

Joule Effect (Magnetostriction)

ϕ2cosel

l=

∆

0=∆

+∆

+∆

b

b

a

a

l

l

Actuator using Terfenol-D

00

05

10

B (T)

800

1000

1200

1400

1600

Magnetostriction (ppm)

-100 -50 0 50 100

-10

-05

00

B (T)

H (kAm)

2 MPa

4 MPa

6 MPa

8 MPa

10 MPa

12 MPa

-100 -50 0 50 100

-200

0

200

400

600

Magnetostriction (ppm)

H (kAm)

2 MPa

4 MPa

6 MPa

8 MPa

10 MPa

12 MPa

600

700

800

900

1000

-4 -3 -2 -1 0 1 2 3 4

0

10

20

30

40

50

60

Displacement (m

icro meter)

I (A)

FIELD

9 kAm

12 kAm

16 kAm

20 kAm

24 kAm

38 kAm

-50 -40 -30 -20 -10 0 10 20 30 40 50

-100

0

100

200

300

400

500

L (PPM)

H (kAm)

9 kAm

12 kAm

16 kAm

20 kAm

24 kAm

38 kAm

Magnetostrictive displacement sensor

Hysteresis loops under

tensile stress σ

(a) Crystalline 68 NiFe

λs = +25 10-6

(b) crystalline pure Ni λs

= -35 10-6

Villari Effect ( Inverse of Joule Effect)

= -35 10-6

(c) amorphous Co-based

alloy

λs = -35 10-6

ϕσλ 2sin2

3sdotsdot= smeE

γ

Permeability depending on the stress

σλmicromicro

1

3

2

Y

J

so

s

r =

γ

Calculated magnetization curves under stress

Variation of magnetization curve by an applied

tensile force (Co-based amorphous alloy)

Alloy Requirement

Materials for magnetoelastic sensors

Why amorphous magnetic materials are important

Stress-strain curves of several materials

Coercivity and hardness of several materials

Principles of magnetoelastic sensors

Non-contact torque sensor

Principle of cross torductor torque

sensor and flux pattern of sensor

poles on the surface of a shaft

a) without and b)with torsional load

Equivalent magnetic circuit of

cross type torque sensor

Helices of principal tensile and compressive stress on the surface of

a shaft subjected to torsion [32] Correlated changes of permeability

are detected by four-branch yoke system with sensing coils 123

and 4 and a common excitation pole

Examples of torque sensors

Four-branch type torque sensor

heads Pole structures realized

by commercial multi-pole

ferrites 14 and 18 min in

diameter (diameter of sensor

h e a d 1 7 a n d 2 4 m m

respectively) respectively)

Principle of Ring Torductor torque transducer

(a b) Physical structure (c) evolution of the

shaft surface under the transducer poles A and BRing torductor for measuring

torque on ship propeller shafts

(shaft diameter ca 500 mm)

(Courtesy ASEA Brown

Boveri AG)

Principal designs of coaxial torque sensors

Schematic diagram of data processing

electronics of a torque sensor

Extensometer (a) Construction of strain sensing element using

amorphous ribbon wound core (b) configuration of lumped

windings

∆E effect of an amorphous FeNi-based

alloy (Fe40 Ni38 Mo4 B18) Hs saturation

field

Magnetically tunable delay line

Torque Sensors using Amorphous wire

Sixtus tonk효과(large Barkhausen효과)

Hysteresis loops of a Wiegand wire for different reset fields

Curie 온도 및Hopkinson효과

Relation between normalised

saturation polarisation and

normalised Curie temperature

Permeability of a Mn-Zn ferrite as

a function of temperature and field

strength

Conclusions

1) Magnetic sensor 는 자동차 공장자동화 항공우주 및 군사용으로많이 사용되고 있다

2) 새로운 소재개발은 자기센서의 성능개발에 직접적인 영향을 준다2) 새로운 소재개발은 자기센서의 성능개발에 직접적인 영향을 준다

3) 센서의 개발을 위해서는 다양한 전공지식이 요구된다

(물리학 재료공학 기계공학 전자공학)

4) 센서분야가 고부가가치를 창출하는 부품사업이다

5) 핵심부품을 생산하는 중소기업의 item으로도 적절하다

sdot

sdotsdot= minus

Hz nT

V10

2

922

0 DnUπ

Air-cored coil output voltage U0 at a magnetic field x frequency product

1 nT middot Hz versus diameter D with number of turns n as parameter

4

22 dDnWW

sdotsdotsdotsdot=

γπ Weight of coil

Coil resistance2

4

d

nDRDC

ρ=

Thermal voltage noisefTRU DCBN ∆= κ4

W

4W

DnfTU BN

sdotsdotsdotsdot∆=

πγρκ

fHnDdTk

DfHW

TkU

UNS

BBN

sdotsdotsdot

=sdotsdotsdot

== 21302

w00 )(28242

σmicroπ

γρmicroπ

Noise voltage

1028

ln286 9minussdot

+minus= αd

DDL

Equivalent circuit diagram of an air-cored induction coil

For single turn loop Dgtgtd

Long single layer solenoid

[H] 10 H][ 10 922

9222

minusminus sdotsdotsdot

=sdotsdotsdot

asympwd

nD

w

nDL

ππ

622

10 101 46

minussdot+sdot

asympwD

nDL

922

10 10 9 3

778 minussdot++sdot

asymphwD

nDL

Short single layer solenoid wgt16D

Multi-layer solenoid Dgtgtwh

( ) 1

370

ndc

DwC r

sdotminussdotsdotsdot

=ε

1

i

2tot minus+=k

C

k

CC

Capacitance C of a coil

Capacitance C of a single-layer coil normalized to

its diameter D versus length-to-diameter ratio wD

of the coil (capacitance C in pF and geometrical

dimensions w and D in cm)

12 minuskk

High permeability core induction coil

Magnetic field pattern around high permeability core

when it is inserted into a homogeneous field It is valid

for low frequencies and if the coil indicated at the middle

of the core is without current

Magnetization of a high permeability core

dt

dnu ci

i Φ

sdotminus= ) ( cosmaxc ci tωsdotΦ=Φ

ci0rc0 maxAHnnU sdotsdotsdotsdot=Φsdotsdot= micromicroωω

HNHHHH )1( minusminus=+= micro

HN

H sdotminus+

=)1(1

1

r

i micro

irdmi HNHHHH )1( minusminus=+= micro

HfAnU sdotsdotsdotsdotsdotsdot= 0cc0 2 micromicroπ

)1(1 r

rc minus+=

micromicro

microN

minus++

minusminus=

infin1)1ln(

11

1 2

22ell mmm

m

mN

10326) (1ln 152

10156) (1ln 262

ell

cyl

++++

=infin

infin

N

N

Induction coil on a cylindrical high permeability core

Demagnetization factorDemagnetization factorN of prolate ellipsoidsand cylindrical rods(descending curves) andcore permeability μc

(ascending curves) ofcylindrical rods versusthe length-to-diameterratio m of the rod withmaterial permeability μr

as parameter

Core permeability μc of cylindrical rods versus thematerial permeability μr with length-to-diameter ratiom of the rod as parameter after

Minimum noise equivalent magnetic field spectral density of an induction coil sensor with high permeability core versus sensor weight Ws (at length-to-diameter ratios m = 50 and 100 permeability μr = 10000 of the core material and f = 1 Hz)

Induction coil sensors with electronic amplifier

II

rKLC

1=ω

II

II

RR

RK

+=

rr

2 i 1

)(

ωω

ωω

ω

D

KF

+

minus

=

+=

II

II

II

2

C

L

R

R

C

L

KD

Frequency responses of the search coil

Frequency responses of thesensitivity SA and the output voltage UA

of an induction coil sensor with a voltageamplifier at a constant magnetic fieldamplitude

Resonance step-up of thesensitivity SA at differentvalues of the damping D

Sensor with transformer coupled negative feedback to the coil

)(i)()(F

0 ωωωω FR

UMUAU A

A sdot

minus=

)( i1

)(

F

0

ωω

ω

FR

MA

FAUU A

sdot+

sdot=

Induction coil connected to a voltage amplifier with

transformer coupled negative feedback to the coil

FR

21

1K0

i1

1

i1

i )(

ωωωωωω

ωω

+sdot

+sdot=

M

RUU A

IIF2 CRL

MAf

sdotsdotsdotsdot

=∆π

Frequency response of the output voltage UA of an induction coil sensor with negative feedback transformer coupled to the coil

Applications of search coil magnetometer

Developed search coil magnetometer using amorphous ribbon

Experimental setup for the effective permeability measurement

Relative permeability depending on the numbers of ribbon(a)

and the air gap between ribbons

Relative permeability depending on the number of ribbons for the different air gap between ribbons

Relative permeability depending on the total number of ribbons for the different air gap between ribbons

10 pT

100 pT

1 pT

Noise spectrum of the developed search coil magnetometer

BJne

E xH

1minus=

neRH

1minus=

22 nP micromicro minus

Hall 효과

Bt

IRU H

HL =

2

22

)( he

eh

Hpne

nPR

micromicromicromicro

+

minus=

Rectangular Hall plate (cc1cc2 current constant sc1sc2

sensor constant I bias current U voltage drop UH Hall

voltage

Physics carrier concentration and kind of carrier measurement

Engineering magnetic field measurement

Current Measurement

Arrangement for noninvasive

current measurement using an iron

core The current to be measured

produces a proportional magnetic

field which can be measured in the

air gap

Characteristic curve produced by

the current

Arrangement for indirect noninvasive

current measurement using the

compensation principle An iron core as

represented in Figure 3-29 is held field

free by injection a current into a

compensating coil wound on the core

which offsets the field generated by the

current being measured The Hall effect

sensor in the air gap serves as a null

indicator

Circuit diagram for AC-power

measurement using a Hall effect

sensor

DC Power Measurement

Circuit diagram for DC-

power measurement using a

Hall effect sensor

Noncontact Position Sensing

Galvanomagnetic components for sensing the position of permanent magnets

and magnetically conductive materials

Current Sensor Based on Hall Sensor

and Magnetic Core for Hybrid Vehicle

KH Yeon1 SD Kim1 and D Son2 1Auto industry co14F Hanshin IT tower Guro Gu Seoul Korea2Hannam UniversityOjung dong 133 Daejeon Rep of Korea

i

Hall sensor

B

I

SB

ring core

B

I10

g

N

Bl S

micro

)( gtgtrmicro

gab core

Current Sensor Based on Hall

Sensor and Magnetic Core

Hall

Effect

Device

CurrentVoltage

applying for

Hall effect device

operation

Output

signals

Magnetic field

Occurred by

current measurement

Signal

process

circuits

Developed Current Sensor

Magnetic core

Hall sensor

PCB

25

30

35

40

45

50

Output voltage V

Current sensor(Open loop type)

Temp 25C

400A model

+400 ~ -400A

SD 000128

Linearity 003

Linearity of the sensor

Characteristics of the Current Sensors

1000A 10 V power supply

-500 -400 -300 -200 -100 0 100 200 300 400 500

00

05

10

15

20

Output voltage V

current A

Temperature 25Linearity 003

Measuring range -400A ~ +400A

1000A Electronic Load

-3

0

3

6

9

12

15

18

dB

Current sensor

DV2 PCB 24pF

40Aturns

Frequency bandwidth

Gain bandwidth 3 MHz

Current 10 A

Temperature 25

Frequency bandwidth 100 kHz

Sensor output voltage vs frequency

at applied current of 40 Aturns

1 10 100

-18

-15

-12

-9

-6

Frequency kHz 측정온도 25

주파수특성 30kHz 이상(3dB 기준)

측정전류 40Aturns(4A 10턴)

측정주파수 100Hz ~ 100kHz

Temperature 25Current 40Aturns

Frequency range 100 Hz ~ 100 kHz

What is Magnetoresistance

Magnetoresistance effect(AMR)

θθθ 2cos2

12sin12cos(

22 minusminus+∆asymp∆ xxxmx hhhRR

32 minusasymp∆ ρρ New effect GMR CMR and GMI

10 ge∆ ρρ

Two bridge configuration for

rotational angle measurement

measurement angle more than 180o

자동차 Engine Management System

Inductive and Eddy Current

Sensors Excited by Permanent Magnets

tNtU dd)( φsdotminus=

construction of an inductive

sensor (courtesy VDO Adolf sensor (courtesy VDO Adolf

Schindling AG)

1) constant socket

2) terminal package

3) permanent magnet

4) cap

5) soft magnetic core

6) coil

7) plate

8) blade connector

γγ

Sensor with yoke Change in the magnetic flux with

varying air gap Continuous lines

minimum air gap dashed lines

maximum air gap

C-shaped sensor

Sensor with radially

magnetized

permanent magnet

Signal Conditioning

Output voltage U of a DC-excited sensor with permanent

magnets when a single iron object passes by

Schematic electrical diagram of an inductive sensor

Linear Variable Differential Transformer

AC-Excited Sensors for Linear Movement

Principle of construction of an LVDT

Electrical circuit of an LVDT

tIMtNU dd dd sdotminus=sdotminus= φ

tIMtIMUUU dd dd 1212 sdotminussdot=minus=

tIMMU dd)( 12 sdotminus=

)(12 xMMMM =minus=

tIxMU dd)( sdot= tI

UxM

dd)( =

Signal Conditioning

power supply

carrier gen

autoampcontrol

LVDTcarrieramp

demod-ulator

phase

shifter

power supply

carrier gen

passivedemod-ulator

LVDTDCamp

Block diagram of a carrier amplifier system

Block diagram of a DC amplifier system

Variable Inductive Sensors

Principle of construction

of the VLP sensor

Principle of a bridge

circuit

lANL r 20 sdotsdotsdot= micromicro

21 BA UUU minus=

21)i(ii( 211 minus+sdot= LLLUU BA ωωω

)21))()((( minus∆minus+∆+∆+sdot= LLLLLLUU BA

)212)(( minus∆+sdot= LLLUU )212)(( minus∆+sdot= LLLUU BA

LLUU BA 21 ∆sdotsdot=

llLL ∆sdot=∆ d d

llLLUU BA ∆sdotsdot= d d)2(1

Applications and Properties

Principle of a construction of a force transducer

(courtesy Hottinger Baldwin Messtechnik)

Vibrationacceleration sensor

Signal Conditioning

Schematic electrical diagram of a force transducer connected with an

amplifier (courtesy Hottinger Baldwin Messtechnik GmbH)

Variable Gap Sensors

)( FeFe2

0 LLllANL micromicromicro +sdotsdot=

FeFe2

0max lANL sdotsdotsdot= micromicro

Construction of a variable gap sensor

Characteristic of a variable gap sensor

Construction of a differential

cross-anchor sensor

Output voltage U versus core

position x plusmn a limits of the

linear rage

Applications of differential cross-anchor sensors

AC-excited Sensors for Rotary Movements

Principle of construction of a synchro

α cos10 sdotsdot= UKU y

)120-( cos10 degsdotsdot= αUKU z

)240-( cos10 degsdotsdot= αUKU x

)120-( sin3100 degsdotsdotsdot=minus= αKUUUU yxyx

)240-( sin3100 degsdotsdotsdot=minus= αKUUUU zyzy

α sin3100 sdotsdotsdot=minus= KUUUU xzxz

Application to the Torque Sensor

Principle of construction of a torque-type synchro

Torque versus angular

difference

)( sin~ rt αα minussdotKM

)( cos~ rt1r αα minussdotUU

Principle of construction of a control-type sensor

Output voltage versus

angular difference

Principle of construction of a differential sychro

Eddy Current Sensors

tBE dd curl minus=JH = curl

0 div =BH(H)B sdot= micro

E(E)J sdot= σ

A B curl= A B curl=

tdd- A E =

)dd( tAJ minus= σ

tdd curl curl AA σmicro minus=

AA) σωmicro iminus= curl )(curl(1

AA) σωmicro i=∆)((1

Eddy Current Tachometer

Construction of a speedometer (courtesy VDO Adolf Schinding AG) 1) spindle 2) bearing

3) holding spring 4) iron yoke 5) eddy current cup 6) shaft of the magnet 7) support of

the magnet 8) temperature compensation 9) permanent magnet 10) torsion spring

Proximity Sensors

Schematic diagram of a proximity sensor

Output current of a proximity switch versus distance

Inductive Flowmeters

)( Btimessdot= υqF

EqF sdot=BE times=υ

)(ds Btimes== υEU )(ds Btimes== υEU

)( Bd timessdot= υU

Bsdotsdotsdot= υdKU

Development of magnetic phase detection

sensor for steam generator tube

Dirac Son1 Kwan-Sang Ryu2 Duck-Gun Park3

1Hannam University Daejeon Rep of Korea2Korea Research Institute of Standards and Science Daejeon Rep of Korea3KoreaAtomic Energy Research Institute Daejeon Rep of Korea

Introduction

The layout of pressurized water reactor (PWR) components

Primary side Secondary side (non-radioactive side)(radioactive side)

The Structure of SG(Steam Generator)(degradation mechanism)

Secondary SidePrimary Side

SCC

A B

A-B

Steam outlet

Anti-vibration

SCC

Fretting

Wall thinning

IGA

U-bend

In commercial power plants SG- height up to 21 m - weight up to 800 tons - 2~4 sets of SG were installed - SG can contain from 3000 to

16000 tubes each about 20 mmin diameter

Primary coolant outlet Primary coolant inlet

Anti-vibrationbars

Tubesupportplate

Tubesheet

IGA

SCC

Pitting

SCC

Inside Tubesheet

Top of Tubesheet

by SSHwang of KAERI

Denting

Sludge pile

in diameter

The SGT is made of nickel basedInconel alloy which is composed of 75 Ni 165Cr and 815Fe

-Degradation mechanism corrosion pitting denting inter granular attack

-Inspection Eddy current Testing(ECT)

Permeability Variation Clusters (PVC)

(Ferro-magnetic phase)

-005

000

005

010

015

m (emug)

1-1

-002

000

002

004

006

008

m (emug)

1-2

-1000 -500 0 500 1000

-015

-010

-005

H ( Am )

-1000 -500 0 500 1000

-006

-004

-002

H ( Am )

The hystresis loop in the fragment of PVC parts of Kori-1 retired SG tube

-004

-002

000

002

004

006

M (emug)

Inconel 600 tested at RT

under tensile stress

1 2 3

4 5 6

7 8 9-004

-002

000

002

004

006

M(emug)

Inconel 600 Heat treated at

602 oC under tensile stress

1 2 3

How can we detect magnetic phase

(PVC)selectively from the flaws in SGT

-3000 -2000 -1000 0 1000 2000 3000

-006

H (Oe)

7 8 9

10 11 12

-3000 -2000 -1000 0 1000 2000 3000

-006

-004

H(Oe)

4 5 6

7 8 9

The hysteresis loop of the tensile tested specimen at room temperature (a) and tensile tested at high temperature (b)

The magnetic phase can be created under the high temperature andpressure conditions which is correspond to the stress corrosion crackingin the SG tube in the NPP(Bruemmer SM Charlot LA amp Henager CH (1988) Corrosion 782)

Principle of ECT

If we can separate magnetic phase selectively from the

flaws using magnetic sensor the reliability of EC in SGT

inspection will be greatly enhanced

Structure of the permeability

sensor

Dimension and photograph of U-shape

sensing yoke

Design of Magnetic Sensor for PVC

sensor sensing yoke

Photograph of the completed sensor front side (above) and rear side (bottom)

R11R12

R10

R8

R6

R9

R13

R7

R14

C18

1 n

C17

C20

C21

D2

DIODE

SIN COS

-

+

U-2A

4

13

2

-

+

U-2B

75

6

8

-

+

U-3A

13

2

8

+5VC19

104

+5V

Schematic diagram of the sensor system

Electronic Circuit of Magnetic Sensor

R20

R

R21

R

-

+

U5AD797

3

26

74

U6

D1

S12

GND3

+VCC4VCC5

IN6

-VCC7

S28

C41

R13

R26

R18

R25

R2210 Ω

R16

R14

R17

10 k

R15

R27

R32

R28

R33

R29

R34

5 k

R30

C29

C37

104

C32473

C39473C40

104

C33

104

C21

104C23

104

C25

104

C26

104

C30

104

C31

104

C35

104

C36

104

C27

104

C28

104

C34

104

C38

104

D3

DIODE

L1

1

2

L2

1

2

L3

1

2

4

-

+

U-4A

4

13

2

-

+

U-4B

75

6

8

-

+

U-5A

4

13

2

-

+

U-5B

75

6

8

-

+

U-6A

4

13

2

-

+

U-6B

75

6

8

C22

104

-5V

+5V

+5V

+5V

+5V

+5V

+5V

U7

D1

S12

GND3

+VCC4

VCC5

IN6

-VCC7

S28

+5V

-5V

-5V

-5V

-5V

-5V

-5V

-5V

-5V

R19

R24

R

R23

R

C24

OUT(X)

OUT(Y)

R1

20 kR210 k

R3

20 kR410 k

C1

104

C8

104

REF43

OUT(X)

OUT(Y)

REF43

U2

+Vcc1

CH02

CH13

CH24

CH35

COMM6

SHDN7

Vref8

+Vcc9

GND10

GND11

DOUT12BUSY13DIN14CS15

DIN16

-

+

U-1A

13

2

8

-

+

U-1B

4

75

6

C410 uF

C5104

DOUT

C210uF

C6104

C3104

DCLK

C7104

DIN

C10

01uF

CS

BUSY

C14 10uF

J1

CON6

123456

D1

DIODE

R5

47K

C9

10uF

C1310uF

Y1

OSC

OUT3

GND2

VCC4

U3

RSTVPP1

GND10

VCC20

XTAL15

XTAL24

P10AIN012P11AIN113P1214P1315P1416P1517P1618P1719

P30RXD2

P31TXD3

P32INT06

P33INT17

P34T08

P35T19

P3711

U4

C1+1

C1-3

C2+4

C2-5

VCC16

GND15

V+2

V-6

R1OUT12

R2OUT9

T1IN11

T2IN10

R1IN13

R2IN8

T1OUT14

T2OUT7

C12 10uF

C16

01uF

C15 10uF

C11

01uF

-5V

+5V

+5V

+5V

+5V

+5V

+5V

+5V

RST

OSC

OSC

RST

DCLKCSDINBUSYDOUT

U1

IN2

GND

4

OUT6

TEMP3

TRIM5

-5V

+5V

Electronic circuit diagram of the magnetic sensor

Photograph of the completed measuring system data acquisition

software in PC and probe scanning system

Experimental Setup for Magnetic Sensor

Reference material Scanning System Software LabVIEW

Reference Material (1) Normal defects and PVCs

Longitudinal and transverse defects

Def W L D Remarks

1 02 500 0213 (20 ) Inner defects

2 02 500 0427 (40 )

3 02 500 0213 (20 )Outer defectsPVC(1018)4 02 500 0427 (40 )

5 02 500 0639 (60 )

6 02 500 0852 (80 )

7 02 500 0639 (60 ) Inner defects

8 02 500 0852 (80 )

- 1 and 2 are inner defects

- 345 and 6 are outer defects with PVC

- 7 and 8 are inner defects

PVC

PVC

Defect Defect

For longitudinal defects and PVC For circumferential defects and PVC

ECT is very difficult to detect circumferential defects

We can distinguish PVCs and defects and longitudinal and circumferential defects

Flux-gate Magnetometer

One core sensor Two core sensor

3-축 flux-gate Magnetometer의 계략도

Sensorpia Co

pro

cess

or(

AV

R)

Sensor 1

RS422

Interface

Mic

ro-p

roce

ssor(

AV

R)

Sensor 2

Sensor 3

Interface

조립된 마그네토미터의 사진

Sensorpia Co

Analog PCB

Digital PCB

Sensorpia Co선형도(linearity)

10

20

30

40

50

60

y-axis

Magnetometer Output (microT)

-60 -50 -40 -30 -20 -10 0 10 20 30 40 50 60

-60

-50

-40

-30

-20

-10

0

10

Y-axis y=099946 x+0015STD 106E-4

Magnetometer Output (

Applied Magnetic Field (microT)

마그네토미터의 noise 특성 Sensorpia Co

1

10

100

y-axis

Magnetometer noise (nT)

0 1 2 3 4 5 6

1E-4

1E-3

001

01

Magnetometer noise (nT)

Frequency (Hz)

Magnetometer for KoDSAT

-150 -100 -50 0 50 100 150

-15

-10

-5

0

5

10

15

Magnetic Moment (Am

2)

Current (mA)

After Thermal Cycle Test

Measured

Resistance 193 ohm

Photograph of Magnetic torquer

Photograph of KoDSAT

Photograph of

3-axis Fluxgate

Magnetometer

Photograph of Magnetic torquer

Application of magnetometer

Moon magnetic fieldmeasurement

Telescope with direction indication

Joule Effect (Magnetostriction)

ϕ2cosel

l=

∆

0=∆

+∆

+∆

b

b

a

a

l

l

Actuator using Terfenol-D

00

05

10

B (T)

800

1000

1200

1400

1600

Magnetostriction (ppm)

-100 -50 0 50 100

-10

-05

00

B (T)

H (kAm)

2 MPa

4 MPa

6 MPa

8 MPa

10 MPa

12 MPa

-100 -50 0 50 100

-200

0

200

400

600

Magnetostriction (ppm)

H (kAm)

2 MPa

4 MPa

6 MPa

8 MPa

10 MPa

12 MPa

600

700

800

900

1000

-4 -3 -2 -1 0 1 2 3 4

0

10

20

30

40

50

60

Displacement (m

icro meter)

I (A)

FIELD

9 kAm

12 kAm

16 kAm

20 kAm

24 kAm

38 kAm

-50 -40 -30 -20 -10 0 10 20 30 40 50

-100

0

100

200

300

400

500

L (PPM)

H (kAm)

9 kAm

12 kAm

16 kAm

20 kAm

24 kAm

38 kAm

Magnetostrictive displacement sensor

Hysteresis loops under

tensile stress σ

(a) Crystalline 68 NiFe

λs = +25 10-6

(b) crystalline pure Ni λs

= -35 10-6

Villari Effect ( Inverse of Joule Effect)

= -35 10-6

(c) amorphous Co-based

alloy

λs = -35 10-6

ϕσλ 2sin2

3sdotsdot= smeE

γ

Permeability depending on the stress

σλmicromicro

1

3

2

Y

J

so

s

r =

γ

Calculated magnetization curves under stress

Variation of magnetization curve by an applied

tensile force (Co-based amorphous alloy)

Alloy Requirement

Materials for magnetoelastic sensors

Why amorphous magnetic materials are important

Stress-strain curves of several materials

Coercivity and hardness of several materials

Principles of magnetoelastic sensors

Non-contact torque sensor

Principle of cross torductor torque

sensor and flux pattern of sensor

poles on the surface of a shaft

a) without and b)with torsional load

Equivalent magnetic circuit of

cross type torque sensor

Helices of principal tensile and compressive stress on the surface of

a shaft subjected to torsion [32] Correlated changes of permeability

are detected by four-branch yoke system with sensing coils 123

and 4 and a common excitation pole

Examples of torque sensors

Four-branch type torque sensor

heads Pole structures realized

by commercial multi-pole

ferrites 14 and 18 min in

diameter (diameter of sensor

h e a d 1 7 a n d 2 4 m m

respectively) respectively)

Principle of Ring Torductor torque transducer

(a b) Physical structure (c) evolution of the

shaft surface under the transducer poles A and BRing torductor for measuring

torque on ship propeller shafts

(shaft diameter ca 500 mm)

(Courtesy ASEA Brown

Boveri AG)

Principal designs of coaxial torque sensors

Schematic diagram of data processing

electronics of a torque sensor

Extensometer (a) Construction of strain sensing element using

amorphous ribbon wound core (b) configuration of lumped

windings

∆E effect of an amorphous FeNi-based

alloy (Fe40 Ni38 Mo4 B18) Hs saturation

field

Magnetically tunable delay line

Torque Sensors using Amorphous wire

Sixtus tonk효과(large Barkhausen효과)

Hysteresis loops of a Wiegand wire for different reset fields

Curie 온도 및Hopkinson효과

Relation between normalised

saturation polarisation and

normalised Curie temperature

Permeability of a Mn-Zn ferrite as

a function of temperature and field

strength

Conclusions

1) Magnetic sensor 는 자동차 공장자동화 항공우주 및 군사용으로많이 사용되고 있다

2) 새로운 소재개발은 자기센서의 성능개발에 직접적인 영향을 준다2) 새로운 소재개발은 자기센서의 성능개발에 직접적인 영향을 준다

3) 센서의 개발을 위해서는 다양한 전공지식이 요구된다

(물리학 재료공학 기계공학 전자공학)

4) 센서분야가 고부가가치를 창출하는 부품사업이다

5) 핵심부품을 생산하는 중소기업의 item으로도 적절하다

4

22 dDnWW

sdotsdotsdotsdot=

γπ Weight of coil

Coil resistance2

4

d

nDRDC

ρ=

Thermal voltage noisefTRU DCBN ∆= κ4

W

4W

DnfTU BN

sdotsdotsdotsdot∆=

πγρκ

fHnDdTk

DfHW

TkU

UNS

BBN

sdotsdotsdot

=sdotsdotsdot

== 21302

w00 )(28242

σmicroπ

γρmicroπ

Noise voltage

1028

ln286 9minussdot

+minus= αd

DDL

Equivalent circuit diagram of an air-cored induction coil

For single turn loop Dgtgtd

Long single layer solenoid

[H] 10 H][ 10 922

9222

minusminus sdotsdotsdot

=sdotsdotsdot

asympwd

nD

w

nDL

ππ

622

10 101 46

minussdot+sdot

asympwD

nDL

922

10 10 9 3

778 minussdot++sdot

asymphwD

nDL

Short single layer solenoid wgt16D

Multi-layer solenoid Dgtgtwh

( ) 1

370

ndc

DwC r

sdotminussdotsdotsdot

=ε

1

i

2tot minus+=k

C

k

CC

Capacitance C of a coil

Capacitance C of a single-layer coil normalized to

its diameter D versus length-to-diameter ratio wD

of the coil (capacitance C in pF and geometrical

dimensions w and D in cm)

12 minuskk

High permeability core induction coil

Magnetic field pattern around high permeability core

when it is inserted into a homogeneous field It is valid

for low frequencies and if the coil indicated at the middle

of the core is without current

Magnetization of a high permeability core

dt

dnu ci

i Φ

sdotminus= ) ( cosmaxc ci tωsdotΦ=Φ

ci0rc0 maxAHnnU sdotsdotsdotsdot=Φsdotsdot= micromicroωω

HNHHHH )1( minusminus=+= micro

HN

H sdotminus+

=)1(1

1

r

i micro

irdmi HNHHHH )1( minusminus=+= micro

HfAnU sdotsdotsdotsdotsdotsdot= 0cc0 2 micromicroπ

)1(1 r

rc minus+=

micromicro

microN

minus++

minusminus=

infin1)1ln(

11

1 2

22ell mmm

m

mN

10326) (1ln 152

10156) (1ln 262

ell

cyl

++++

=infin

infin

N

N

Induction coil on a cylindrical high permeability core

Demagnetization factorDemagnetization factorN of prolate ellipsoidsand cylindrical rods(descending curves) andcore permeability μc

(ascending curves) ofcylindrical rods versusthe length-to-diameterratio m of the rod withmaterial permeability μr

as parameter

Core permeability μc of cylindrical rods versus thematerial permeability μr with length-to-diameter ratiom of the rod as parameter after

Minimum noise equivalent magnetic field spectral density of an induction coil sensor with high permeability core versus sensor weight Ws (at length-to-diameter ratios m = 50 and 100 permeability μr = 10000 of the core material and f = 1 Hz)

Induction coil sensors with electronic amplifier

II

rKLC

1=ω

II

II

RR

RK

+=

rr

2 i 1

)(

ωω

ωω

ω

D

KF

+

minus

=

+=

II

II

II

2

C

L

R

R

C

L

KD

Frequency responses of the search coil

Frequency responses of thesensitivity SA and the output voltage UA

of an induction coil sensor with a voltageamplifier at a constant magnetic fieldamplitude

Resonance step-up of thesensitivity SA at differentvalues of the damping D

Sensor with transformer coupled negative feedback to the coil

)(i)()(F

0 ωωωω FR

UMUAU A

A sdot

minus=

)( i1

)(

F

0

ωω

ω

FR

MA

FAUU A

sdot+

sdot=

Induction coil connected to a voltage amplifier with

transformer coupled negative feedback to the coil

FR

21

1K0

i1

1

i1

i )(

ωωωωωω

ωω

+sdot

+sdot=

M

RUU A

IIF2 CRL

MAf

sdotsdotsdotsdot

=∆π

Frequency response of the output voltage UA of an induction coil sensor with negative feedback transformer coupled to the coil

Applications of search coil magnetometer

Developed search coil magnetometer using amorphous ribbon

Experimental setup for the effective permeability measurement

Relative permeability depending on the numbers of ribbon(a)

and the air gap between ribbons

Relative permeability depending on the number of ribbons for the different air gap between ribbons

Relative permeability depending on the total number of ribbons for the different air gap between ribbons

10 pT

100 pT

1 pT

Noise spectrum of the developed search coil magnetometer

BJne

E xH

1minus=

neRH

1minus=

22 nP micromicro minus

Hall 효과

Bt

IRU H

HL =

2

22

)( he

eh

Hpne

nPR

micromicromicromicro

+

minus=

Rectangular Hall plate (cc1cc2 current constant sc1sc2

sensor constant I bias current U voltage drop UH Hall

voltage

Physics carrier concentration and kind of carrier measurement

Engineering magnetic field measurement

Current Measurement

Arrangement for noninvasive

current measurement using an iron

core The current to be measured

produces a proportional magnetic

field which can be measured in the

air gap

Characteristic curve produced by

the current

Arrangement for indirect noninvasive

current measurement using the

compensation principle An iron core as

represented in Figure 3-29 is held field

free by injection a current into a

compensating coil wound on the core

which offsets the field generated by the

current being measured The Hall effect

sensor in the air gap serves as a null

indicator

Circuit diagram for AC-power

measurement using a Hall effect

sensor

DC Power Measurement

Circuit diagram for DC-

power measurement using a

Hall effect sensor

Noncontact Position Sensing

Galvanomagnetic components for sensing the position of permanent magnets

and magnetically conductive materials

Current Sensor Based on Hall Sensor

and Magnetic Core for Hybrid Vehicle

KH Yeon1 SD Kim1 and D Son2 1Auto industry co14F Hanshin IT tower Guro Gu Seoul Korea2Hannam UniversityOjung dong 133 Daejeon Rep of Korea

i

Hall sensor

B

I

SB

ring core

B

I10

g

N

Bl S

micro

)( gtgtrmicro

gab core

Current Sensor Based on Hall

Sensor and Magnetic Core

Hall

Effect

Device

CurrentVoltage

applying for

Hall effect device

operation

Output

signals

Magnetic field

Occurred by

current measurement

Signal

process

circuits

Developed Current Sensor

Magnetic core

Hall sensor

PCB

25

30

35

40

45

50

Output voltage V

Current sensor(Open loop type)

Temp 25C

400A model

+400 ~ -400A

SD 000128

Linearity 003

Linearity of the sensor

Characteristics of the Current Sensors

1000A 10 V power supply

-500 -400 -300 -200 -100 0 100 200 300 400 500

00

05

10

15

20

Output voltage V

current A

Temperature 25Linearity 003

Measuring range -400A ~ +400A

1000A Electronic Load

-3

0

3

6

9

12

15

18

dB

Current sensor

DV2 PCB 24pF

40Aturns

Frequency bandwidth

Gain bandwidth 3 MHz

Current 10 A

Temperature 25

Frequency bandwidth 100 kHz

Sensor output voltage vs frequency

at applied current of 40 Aturns

1 10 100

-18

-15

-12

-9

-6

Frequency kHz 측정온도 25

주파수특성 30kHz 이상(3dB 기준)

측정전류 40Aturns(4A 10턴)

측정주파수 100Hz ~ 100kHz

Temperature 25Current 40Aturns

Frequency range 100 Hz ~ 100 kHz

What is Magnetoresistance

Magnetoresistance effect(AMR)

θθθ 2cos2

12sin12cos(

22 minusminus+∆asymp∆ xxxmx hhhRR

32 minusasymp∆ ρρ New effect GMR CMR and GMI

10 ge∆ ρρ

Two bridge configuration for

rotational angle measurement

measurement angle more than 180o

자동차 Engine Management System

Inductive and Eddy Current

Sensors Excited by Permanent Magnets

tNtU dd)( φsdotminus=

construction of an inductive

sensor (courtesy VDO Adolf sensor (courtesy VDO Adolf

Schindling AG)

1) constant socket

2) terminal package

3) permanent magnet

4) cap

5) soft magnetic core

6) coil

7) plate

8) blade connector

γγ

Sensor with yoke Change in the magnetic flux with

varying air gap Continuous lines

minimum air gap dashed lines

maximum air gap

C-shaped sensor

Sensor with radially

magnetized

permanent magnet

Signal Conditioning

Output voltage U of a DC-excited sensor with permanent

magnets when a single iron object passes by

Schematic electrical diagram of an inductive sensor

Linear Variable Differential Transformer

AC-Excited Sensors for Linear Movement

Principle of construction of an LVDT

Electrical circuit of an LVDT

tIMtNU dd dd sdotminus=sdotminus= φ

tIMtIMUUU dd dd 1212 sdotminussdot=minus=

tIMMU dd)( 12 sdotminus=

)(12 xMMMM =minus=

tIxMU dd)( sdot= tI

UxM

dd)( =

Signal Conditioning

power supply

carrier gen

autoampcontrol

LVDTcarrieramp

demod-ulator

phase

shifter

power supply

carrier gen

passivedemod-ulator

LVDTDCamp

Block diagram of a carrier amplifier system

Block diagram of a DC amplifier system

Variable Inductive Sensors

Principle of construction

of the VLP sensor

Principle of a bridge

circuit

lANL r 20 sdotsdotsdot= micromicro

21 BA UUU minus=

21)i(ii( 211 minus+sdot= LLLUU BA ωωω

)21))()((( minus∆minus+∆+∆+sdot= LLLLLLUU BA

)212)(( minus∆+sdot= LLLUU )212)(( minus∆+sdot= LLLUU BA

LLUU BA 21 ∆sdotsdot=

llLL ∆sdot=∆ d d

llLLUU BA ∆sdotsdot= d d)2(1

Applications and Properties

Principle of a construction of a force transducer

(courtesy Hottinger Baldwin Messtechnik)

Vibrationacceleration sensor

Signal Conditioning

Schematic electrical diagram of a force transducer connected with an

amplifier (courtesy Hottinger Baldwin Messtechnik GmbH)

Variable Gap Sensors

)( FeFe2

0 LLllANL micromicromicro +sdotsdot=

FeFe2

0max lANL sdotsdotsdot= micromicro

Construction of a variable gap sensor

Characteristic of a variable gap sensor

Construction of a differential

cross-anchor sensor

Output voltage U versus core

position x plusmn a limits of the

linear rage

Applications of differential cross-anchor sensors

AC-excited Sensors for Rotary Movements

Principle of construction of a synchro

α cos10 sdotsdot= UKU y

)120-( cos10 degsdotsdot= αUKU z

)240-( cos10 degsdotsdot= αUKU x

)120-( sin3100 degsdotsdotsdot=minus= αKUUUU yxyx

)240-( sin3100 degsdotsdotsdot=minus= αKUUUU zyzy

α sin3100 sdotsdotsdot=minus= KUUUU xzxz

Application to the Torque Sensor

Principle of construction of a torque-type synchro

Torque versus angular

difference

)( sin~ rt αα minussdotKM

)( cos~ rt1r αα minussdotUU

Principle of construction of a control-type sensor

Output voltage versus

angular difference

Principle of construction of a differential sychro

Eddy Current Sensors

tBE dd curl minus=JH = curl

0 div =BH(H)B sdot= micro

E(E)J sdot= σ

A B curl= A B curl=

tdd- A E =

)dd( tAJ minus= σ

tdd curl curl AA σmicro minus=

AA) σωmicro iminus= curl )(curl(1

AA) σωmicro i=∆)((1

Eddy Current Tachometer

Construction of a speedometer (courtesy VDO Adolf Schinding AG) 1) spindle 2) bearing

3) holding spring 4) iron yoke 5) eddy current cup 6) shaft of the magnet 7) support of

the magnet 8) temperature compensation 9) permanent magnet 10) torsion spring

Proximity Sensors

Schematic diagram of a proximity sensor

Output current of a proximity switch versus distance

Inductive Flowmeters

)( Btimessdot= υqF

EqF sdot=BE times=υ

)(ds Btimes== υEU )(ds Btimes== υEU

)( Bd timessdot= υU

Bsdotsdotsdot= υdKU

Development of magnetic phase detection

sensor for steam generator tube

Dirac Son1 Kwan-Sang Ryu2 Duck-Gun Park3

1Hannam University Daejeon Rep of Korea2Korea Research Institute of Standards and Science Daejeon Rep of Korea3KoreaAtomic Energy Research Institute Daejeon Rep of Korea

Introduction

The layout of pressurized water reactor (PWR) components

Primary side Secondary side (non-radioactive side)(radioactive side)

The Structure of SG(Steam Generator)(degradation mechanism)

Secondary SidePrimary Side

SCC

A B

A-B

Steam outlet

Anti-vibration

SCC

Fretting

Wall thinning

IGA

U-bend

In commercial power plants SG- height up to 21 m - weight up to 800 tons - 2~4 sets of SG were installed - SG can contain from 3000 to

16000 tubes each about 20 mmin diameter

Primary coolant outlet Primary coolant inlet

Anti-vibrationbars

Tubesupportplate

Tubesheet

IGA

SCC

Pitting

SCC

Inside Tubesheet

Top of Tubesheet

by SSHwang of KAERI

Denting

Sludge pile

in diameter

The SGT is made of nickel basedInconel alloy which is composed of 75 Ni 165Cr and 815Fe

-Degradation mechanism corrosion pitting denting inter granular attack

-Inspection Eddy current Testing(ECT)

Permeability Variation Clusters (PVC)

(Ferro-magnetic phase)

-005

000

005

010

015

m (emug)

1-1

-002

000

002

004

006

008

m (emug)

1-2

-1000 -500 0 500 1000

-015

-010

-005

H ( Am )

-1000 -500 0 500 1000

-006

-004

-002

H ( Am )

The hystresis loop in the fragment of PVC parts of Kori-1 retired SG tube

-004

-002

000

002

004

006

M (emug)

Inconel 600 tested at RT

under tensile stress

1 2 3

4 5 6

7 8 9-004

-002

000

002

004

006

M(emug)

Inconel 600 Heat treated at

602 oC under tensile stress

1 2 3

How can we detect magnetic phase

(PVC)selectively from the flaws in SGT

-3000 -2000 -1000 0 1000 2000 3000

-006

H (Oe)

7 8 9

10 11 12

-3000 -2000 -1000 0 1000 2000 3000

-006

-004

H(Oe)

4 5 6

7 8 9

The hysteresis loop of the tensile tested specimen at room temperature (a) and tensile tested at high temperature (b)

The magnetic phase can be created under the high temperature andpressure conditions which is correspond to the stress corrosion crackingin the SG tube in the NPP(Bruemmer SM Charlot LA amp Henager CH (1988) Corrosion 782)

Principle of ECT

If we can separate magnetic phase selectively from the

flaws using magnetic sensor the reliability of EC in SGT

inspection will be greatly enhanced

Structure of the permeability

sensor

Dimension and photograph of U-shape

sensing yoke

Design of Magnetic Sensor for PVC

sensor sensing yoke

Photograph of the completed sensor front side (above) and rear side (bottom)

R11R12

R10

R8

R6

R9

R13

R7

R14

C18

1 n

C17

C20

C21

D2

DIODE

SIN COS

-

+

U-2A

4

13

2

-

+

U-2B

75

6

8

-

+

U-3A

13

2

8

+5VC19

104

+5V

Schematic diagram of the sensor system

Electronic Circuit of Magnetic Sensor

R20

R

R21

R

-

+

U5AD797

3

26

74

U6

D1

S12

GND3

+VCC4VCC5

IN6

-VCC7

S28

C41

R13

R26

R18

R25

R2210 Ω

R16

R14

R17

10 k

R15

R27

R32

R28

R33

R29

R34

5 k

R30

C29

C37

104

C32473

C39473C40

104

C33

104

C21

104C23

104

C25

104

C26

104

C30

104

C31

104

C35

104

C36

104

C27

104

C28

104

C34

104

C38

104

D3

DIODE

L1

1

2

L2

1

2

L3

1

2

4

-

+

U-4A

4

13

2

-

+

U-4B

75

6

8

-

+

U-5A

4

13

2

-

+

U-5B

75

6

8

-

+

U-6A

4

13

2

-

+

U-6B

75

6

8

C22

104

-5V

+5V

+5V

+5V

+5V

+5V

+5V

U7

D1

S12

GND3

+VCC4

VCC5

IN6

-VCC7

S28

+5V

-5V

-5V

-5V

-5V

-5V

-5V

-5V

-5V

R19

R24

R

R23

R

C24

OUT(X)

OUT(Y)

R1

20 kR210 k

R3

20 kR410 k

C1

104

C8

104

REF43

OUT(X)

OUT(Y)

REF43

U2

+Vcc1

CH02

CH13

CH24

CH35

COMM6

SHDN7

Vref8

+Vcc9

GND10

GND11

DOUT12BUSY13DIN14CS15

DIN16

-

+

U-1A

13

2

8

-

+

U-1B

4

75

6

C410 uF

C5104

DOUT

C210uF

C6104

C3104

DCLK

C7104

DIN

C10

01uF

CS

BUSY

C14 10uF

J1

CON6

123456

D1

DIODE

R5

47K

C9

10uF

C1310uF

Y1

OSC

OUT3

GND2

VCC4

U3

RSTVPP1

GND10

VCC20

XTAL15

XTAL24

P10AIN012P11AIN113P1214P1315P1416P1517P1618P1719

P30RXD2

P31TXD3

P32INT06

P33INT17

P34T08

P35T19

P3711

U4

C1+1

C1-3

C2+4

C2-5

VCC16

GND15

V+2

V-6

R1OUT12

R2OUT9

T1IN11

T2IN10

R1IN13

R2IN8

T1OUT14

T2OUT7

C12 10uF

C16

01uF

C15 10uF

C11

01uF

-5V

+5V

+5V

+5V

+5V

+5V

+5V

+5V

RST

OSC

OSC

RST

DCLKCSDINBUSYDOUT

U1

IN2

GND

4

OUT6

TEMP3

TRIM5

-5V

+5V

Electronic circuit diagram of the magnetic sensor

Photograph of the completed measuring system data acquisition

software in PC and probe scanning system

Experimental Setup for Magnetic Sensor

Reference material Scanning System Software LabVIEW

Reference Material (1) Normal defects and PVCs

Longitudinal and transverse defects

Def W L D Remarks

1 02 500 0213 (20 ) Inner defects

2 02 500 0427 (40 )

3 02 500 0213 (20 )Outer defectsPVC(1018)4 02 500 0427 (40 )

5 02 500 0639 (60 )

6 02 500 0852 (80 )

7 02 500 0639 (60 ) Inner defects

8 02 500 0852 (80 )

- 1 and 2 are inner defects

- 345 and 6 are outer defects with PVC

- 7 and 8 are inner defects

PVC

PVC

Defect Defect

For longitudinal defects and PVC For circumferential defects and PVC

ECT is very difficult to detect circumferential defects

We can distinguish PVCs and defects and longitudinal and circumferential defects

Flux-gate Magnetometer

One core sensor Two core sensor

3-축 flux-gate Magnetometer의 계략도

Sensorpia Co

pro

cess

or(

AV

R)

Sensor 1

RS422

Interface

Mic

ro-p

roce

ssor(

AV

R)

Sensor 2

Sensor 3

Interface

조립된 마그네토미터의 사진

Sensorpia Co

Analog PCB

Digital PCB

Sensorpia Co선형도(linearity)

10

20

30

40

50

60

y-axis

Magnetometer Output (microT)

-60 -50 -40 -30 -20 -10 0 10 20 30 40 50 60

-60

-50

-40

-30

-20

-10

0

10

Y-axis y=099946 x+0015STD 106E-4

Magnetometer Output (

Applied Magnetic Field (microT)

마그네토미터의 noise 특성 Sensorpia Co

1

10

100

y-axis

Magnetometer noise (nT)

0 1 2 3 4 5 6

1E-4

1E-3

001

01

Magnetometer noise (nT)

Frequency (Hz)

Magnetometer for KoDSAT

-150 -100 -50 0 50 100 150

-15

-10

-5

0

5

10

15

Magnetic Moment (Am

2)

Current (mA)

After Thermal Cycle Test

Measured

Resistance 193 ohm

Photograph of Magnetic torquer

Photograph of KoDSAT

Photograph of

3-axis Fluxgate

Magnetometer

Photograph of Magnetic torquer

Application of magnetometer

Moon magnetic fieldmeasurement

Telescope with direction indication

Joule Effect (Magnetostriction)

ϕ2cosel

l=

∆

0=∆

+∆

+∆

b

b

a

a

l

l

Actuator using Terfenol-D

00

05

10

B (T)

800

1000

1200

1400

1600

Magnetostriction (ppm)

-100 -50 0 50 100

-10

-05

00

B (T)

H (kAm)

2 MPa

4 MPa

6 MPa

8 MPa

10 MPa

12 MPa

-100 -50 0 50 100

-200

0

200

400

600

Magnetostriction (ppm)

H (kAm)

2 MPa

4 MPa

6 MPa

8 MPa

10 MPa

12 MPa

600

700

800

900

1000

-4 -3 -2 -1 0 1 2 3 4

0

10

20

30

40

50

60

Displacement (m

icro meter)

I (A)

FIELD

9 kAm

12 kAm

16 kAm

20 kAm

24 kAm

38 kAm

-50 -40 -30 -20 -10 0 10 20 30 40 50

-100

0

100

200

300

400

500

L (PPM)

H (kAm)

9 kAm

12 kAm

16 kAm

20 kAm

24 kAm

38 kAm

Magnetostrictive displacement sensor

Hysteresis loops under

tensile stress σ

(a) Crystalline 68 NiFe

λs = +25 10-6

(b) crystalline pure Ni λs

= -35 10-6

Villari Effect ( Inverse of Joule Effect)

= -35 10-6

(c) amorphous Co-based

alloy

λs = -35 10-6

ϕσλ 2sin2

3sdotsdot= smeE

γ

Permeability depending on the stress

σλmicromicro

1

3

2

Y

J

so

s

r =

γ

Calculated magnetization curves under stress

Variation of magnetization curve by an applied

tensile force (Co-based amorphous alloy)

Alloy Requirement

Materials for magnetoelastic sensors

Why amorphous magnetic materials are important

Stress-strain curves of several materials

Coercivity and hardness of several materials

Principles of magnetoelastic sensors

Non-contact torque sensor

Principle of cross torductor torque

sensor and flux pattern of sensor

poles on the surface of a shaft

a) without and b)with torsional load

Equivalent magnetic circuit of

cross type torque sensor

Helices of principal tensile and compressive stress on the surface of

a shaft subjected to torsion [32] Correlated changes of permeability

are detected by four-branch yoke system with sensing coils 123

and 4 and a common excitation pole

Examples of torque sensors

Four-branch type torque sensor

heads Pole structures realized

by commercial multi-pole

ferrites 14 and 18 min in

diameter (diameter of sensor

h e a d 1 7 a n d 2 4 m m

respectively) respectively)

Principle of Ring Torductor torque transducer

(a b) Physical structure (c) evolution of the

shaft surface under the transducer poles A and BRing torductor for measuring

torque on ship propeller shafts

(shaft diameter ca 500 mm)

(Courtesy ASEA Brown

Boveri AG)

Principal designs of coaxial torque sensors

Schematic diagram of data processing

electronics of a torque sensor

Extensometer (a) Construction of strain sensing element using

amorphous ribbon wound core (b) configuration of lumped

windings

∆E effect of an amorphous FeNi-based

alloy (Fe40 Ni38 Mo4 B18) Hs saturation

field

Magnetically tunable delay line

Torque Sensors using Amorphous wire

Sixtus tonk효과(large Barkhausen효과)

Hysteresis loops of a Wiegand wire for different reset fields

Curie 온도 및Hopkinson효과

Relation between normalised

saturation polarisation and

normalised Curie temperature

Permeability of a Mn-Zn ferrite as

a function of temperature and field

strength

Conclusions

1) Magnetic sensor 는 자동차 공장자동화 항공우주 및 군사용으로많이 사용되고 있다

2) 새로운 소재개발은 자기센서의 성능개발에 직접적인 영향을 준다2) 새로운 소재개발은 자기센서의 성능개발에 직접적인 영향을 준다

3) 센서의 개발을 위해서는 다양한 전공지식이 요구된다

(물리학 재료공학 기계공학 전자공학)

4) 센서분야가 고부가가치를 창출하는 부품사업이다

5) 핵심부품을 생산하는 중소기업의 item으로도 적절하다

1028

ln286 9minussdot

+minus= αd

DDL

Equivalent circuit diagram of an air-cored induction coil

For single turn loop Dgtgtd

Long single layer solenoid

[H] 10 H][ 10 922

9222

minusminus sdotsdotsdot

=sdotsdotsdot

asympwd

nD

w

nDL

ππ

622

10 101 46

minussdot+sdot

asympwD

nDL

922

10 10 9 3

778 minussdot++sdot

asymphwD

nDL

Short single layer solenoid wgt16D

Multi-layer solenoid Dgtgtwh

( ) 1

370

ndc

DwC r

sdotminussdotsdotsdot

=ε

1

i

2tot minus+=k

C

k

CC

Capacitance C of a coil

Capacitance C of a single-layer coil normalized to

its diameter D versus length-to-diameter ratio wD

of the coil (capacitance C in pF and geometrical

dimensions w and D in cm)

12 minuskk

High permeability core induction coil

Magnetic field pattern around high permeability core

when it is inserted into a homogeneous field It is valid

for low frequencies and if the coil indicated at the middle

of the core is without current

Magnetization of a high permeability core

dt

dnu ci

i Φ

sdotminus= ) ( cosmaxc ci tωsdotΦ=Φ

ci0rc0 maxAHnnU sdotsdotsdotsdot=Φsdotsdot= micromicroωω

HNHHHH )1( minusminus=+= micro

HN

H sdotminus+

=)1(1

1

r

i micro

irdmi HNHHHH )1( minusminus=+= micro

HfAnU sdotsdotsdotsdotsdotsdot= 0cc0 2 micromicroπ

)1(1 r

rc minus+=

micromicro

microN

minus++

minusminus=

infin1)1ln(

11

1 2

22ell mmm

m

mN

10326) (1ln 152

10156) (1ln 262

ell

cyl

++++

=infin

infin

N

N

Induction coil on a cylindrical high permeability core

Demagnetization factorDemagnetization factorN of prolate ellipsoidsand cylindrical rods(descending curves) andcore permeability μc

(ascending curves) ofcylindrical rods versusthe length-to-diameterratio m of the rod withmaterial permeability μr

as parameter

Core permeability μc of cylindrical rods versus thematerial permeability μr with length-to-diameter ratiom of the rod as parameter after

Minimum noise equivalent magnetic field spectral density of an induction coil sensor with high permeability core versus sensor weight Ws (at length-to-diameter ratios m = 50 and 100 permeability μr = 10000 of the core material and f = 1 Hz)

Induction coil sensors with electronic amplifier

II

rKLC

1=ω

II

II

RR

RK

+=

rr

2 i 1

)(

ωω

ωω

ω

D

KF

+

minus

=

+=

II

II

II

2

C

L

R

R

C

L

KD

Frequency responses of the search coil

Frequency responses of thesensitivity SA and the output voltage UA

of an induction coil sensor with a voltageamplifier at a constant magnetic fieldamplitude

Resonance step-up of thesensitivity SA at differentvalues of the damping D

Sensor with transformer coupled negative feedback to the coil

)(i)()(F

0 ωωωω FR

UMUAU A

A sdot

minus=

)( i1

)(

F

0

ωω

ω

FR

MA

FAUU A

sdot+

sdot=

Induction coil connected to a voltage amplifier with

transformer coupled negative feedback to the coil

FR

21

1K0

i1

1

i1

i )(

ωωωωωω

ωω

+sdot

+sdot=

M

RUU A

IIF2 CRL

MAf

sdotsdotsdotsdot

=∆π

Frequency response of the output voltage UA of an induction coil sensor with negative feedback transformer coupled to the coil

Applications of search coil magnetometer

Developed search coil magnetometer using amorphous ribbon

Experimental setup for the effective permeability measurement

Relative permeability depending on the numbers of ribbon(a)

and the air gap between ribbons

Relative permeability depending on the number of ribbons for the different air gap between ribbons

Relative permeability depending on the total number of ribbons for the different air gap between ribbons

10 pT

100 pT

1 pT

Noise spectrum of the developed search coil magnetometer

BJne

E xH

1minus=

neRH

1minus=

22 nP micromicro minus

Hall 효과

Bt

IRU H

HL =

2

22

)( he

eh

Hpne

nPR

micromicromicromicro

+

minus=

Rectangular Hall plate (cc1cc2 current constant sc1sc2

sensor constant I bias current U voltage drop UH Hall

voltage

Physics carrier concentration and kind of carrier measurement

Engineering magnetic field measurement

Current Measurement

Arrangement for noninvasive

current measurement using an iron

core The current to be measured

produces a proportional magnetic

field which can be measured in the

air gap

Characteristic curve produced by

the current

Arrangement for indirect noninvasive

current measurement using the

compensation principle An iron core as

represented in Figure 3-29 is held field

free by injection a current into a

compensating coil wound on the core

which offsets the field generated by the

current being measured The Hall effect

sensor in the air gap serves as a null

indicator

Circuit diagram for AC-power

measurement using a Hall effect

sensor

DC Power Measurement

Circuit diagram for DC-

power measurement using a

Hall effect sensor

Noncontact Position Sensing

Galvanomagnetic components for sensing the position of permanent magnets

and magnetically conductive materials

Current Sensor Based on Hall Sensor

and Magnetic Core for Hybrid Vehicle

KH Yeon1 SD Kim1 and D Son2 1Auto industry co14F Hanshin IT tower Guro Gu Seoul Korea2Hannam UniversityOjung dong 133 Daejeon Rep of Korea

i

Hall sensor

B

I

SB

ring core

B

I10

g

N

Bl S

micro

)( gtgtrmicro

gab core

Current Sensor Based on Hall

Sensor and Magnetic Core

Hall

Effect

Device

CurrentVoltage

applying for

Hall effect device

operation

Output

signals

Magnetic field

Occurred by

current measurement

Signal

process

circuits

Developed Current Sensor

Magnetic core

Hall sensor

PCB

25

30

35

40

45

50

Output voltage V

Current sensor(Open loop type)

Temp 25C

400A model

+400 ~ -400A

SD 000128

Linearity 003

Linearity of the sensor

Characteristics of the Current Sensors

1000A 10 V power supply

-500 -400 -300 -200 -100 0 100 200 300 400 500

00

05

10

15

20

Output voltage V

current A

Temperature 25Linearity 003

Measuring range -400A ~ +400A

1000A Electronic Load

-3

0

3

6

9

12

15

18

dB

Current sensor

DV2 PCB 24pF

40Aturns

Frequency bandwidth

Gain bandwidth 3 MHz

Current 10 A

Temperature 25

Frequency bandwidth 100 kHz

Sensor output voltage vs frequency

at applied current of 40 Aturns

1 10 100

-18

-15

-12

-9

-6

Frequency kHz 측정온도 25

주파수특성 30kHz 이상(3dB 기준)

측정전류 40Aturns(4A 10턴)

측정주파수 100Hz ~ 100kHz

Temperature 25Current 40Aturns

Frequency range 100 Hz ~ 100 kHz

What is Magnetoresistance

Magnetoresistance effect(AMR)

θθθ 2cos2

12sin12cos(

22 minusminus+∆asymp∆ xxxmx hhhRR

32 minusasymp∆ ρρ New effect GMR CMR and GMI

10 ge∆ ρρ

Two bridge configuration for

rotational angle measurement

measurement angle more than 180o

자동차 Engine Management System

Inductive and Eddy Current

Sensors Excited by Permanent Magnets

tNtU dd)( φsdotminus=

construction of an inductive

sensor (courtesy VDO Adolf sensor (courtesy VDO Adolf

Schindling AG)

1) constant socket

2) terminal package

3) permanent magnet

4) cap

5) soft magnetic core

6) coil

7) plate

8) blade connector

γγ

Sensor with yoke Change in the magnetic flux with

varying air gap Continuous lines

minimum air gap dashed lines

maximum air gap

C-shaped sensor

Sensor with radially

magnetized

permanent magnet

Signal Conditioning

Output voltage U of a DC-excited sensor with permanent

magnets when a single iron object passes by

Schematic electrical diagram of an inductive sensor

Linear Variable Differential Transformer

AC-Excited Sensors for Linear Movement

Principle of construction of an LVDT

Electrical circuit of an LVDT

tIMtNU dd dd sdotminus=sdotminus= φ

tIMtIMUUU dd dd 1212 sdotminussdot=minus=

tIMMU dd)( 12 sdotminus=

)(12 xMMMM =minus=

tIxMU dd)( sdot= tI

UxM

dd)( =

Signal Conditioning

power supply

carrier gen

autoampcontrol

LVDTcarrieramp

demod-ulator

phase

shifter

power supply

carrier gen

passivedemod-ulator

LVDTDCamp

Block diagram of a carrier amplifier system

Block diagram of a DC amplifier system

Variable Inductive Sensors

Principle of construction

of the VLP sensor

Principle of a bridge

circuit

lANL r 20 sdotsdotsdot= micromicro

21 BA UUU minus=

21)i(ii( 211 minus+sdot= LLLUU BA ωωω

)21))()((( minus∆minus+∆+∆+sdot= LLLLLLUU BA

)212)(( minus∆+sdot= LLLUU )212)(( minus∆+sdot= LLLUU BA

LLUU BA 21 ∆sdotsdot=

llLL ∆sdot=∆ d d

llLLUU BA ∆sdotsdot= d d)2(1

Applications and Properties

Principle of a construction of a force transducer

(courtesy Hottinger Baldwin Messtechnik)

Vibrationacceleration sensor

Signal Conditioning

Schematic electrical diagram of a force transducer connected with an

amplifier (courtesy Hottinger Baldwin Messtechnik GmbH)

Variable Gap Sensors

)( FeFe2

0 LLllANL micromicromicro +sdotsdot=

FeFe2

0max lANL sdotsdotsdot= micromicro

Construction of a variable gap sensor

Characteristic of a variable gap sensor

Construction of a differential

cross-anchor sensor

Output voltage U versus core

position x plusmn a limits of the

linear rage

Applications of differential cross-anchor sensors

AC-excited Sensors for Rotary Movements

Principle of construction of a synchro

α cos10 sdotsdot= UKU y

)120-( cos10 degsdotsdot= αUKU z

)240-( cos10 degsdotsdot= αUKU x

)120-( sin3100 degsdotsdotsdot=minus= αKUUUU yxyx

)240-( sin3100 degsdotsdotsdot=minus= αKUUUU zyzy

α sin3100 sdotsdotsdot=minus= KUUUU xzxz

Application to the Torque Sensor

Principle of construction of a torque-type synchro

Torque versus angular

difference

)( sin~ rt αα minussdotKM

)( cos~ rt1r αα minussdotUU

Principle of construction of a control-type sensor

Output voltage versus

angular difference

Principle of construction of a differential sychro

Eddy Current Sensors

tBE dd curl minus=JH = curl

0 div =BH(H)B sdot= micro

E(E)J sdot= σ

A B curl= A B curl=

tdd- A E =

)dd( tAJ minus= σ

tdd curl curl AA σmicro minus=

AA) σωmicro iminus= curl )(curl(1

AA) σωmicro i=∆)((1

Eddy Current Tachometer

Construction of a speedometer (courtesy VDO Adolf Schinding AG) 1) spindle 2) bearing

3) holding spring 4) iron yoke 5) eddy current cup 6) shaft of the magnet 7) support of

the magnet 8) temperature compensation 9) permanent magnet 10) torsion spring

Proximity Sensors

Schematic diagram of a proximity sensor

Output current of a proximity switch versus distance

Inductive Flowmeters

)( Btimessdot= υqF

EqF sdot=BE times=υ

)(ds Btimes== υEU )(ds Btimes== υEU

)( Bd timessdot= υU

Bsdotsdotsdot= υdKU

Development of magnetic phase detection

sensor for steam generator tube

Dirac Son1 Kwan-Sang Ryu2 Duck-Gun Park3

1Hannam University Daejeon Rep of Korea2Korea Research Institute of Standards and Science Daejeon Rep of Korea3KoreaAtomic Energy Research Institute Daejeon Rep of Korea

Introduction

The layout of pressurized water reactor (PWR) components

Primary side Secondary side (non-radioactive side)(radioactive side)

The Structure of SG(Steam Generator)(degradation mechanism)

Secondary SidePrimary Side

SCC

A B

A-B

Steam outlet

Anti-vibration

SCC

Fretting

Wall thinning

IGA

U-bend

In commercial power plants SG- height up to 21 m - weight up to 800 tons - 2~4 sets of SG were installed - SG can contain from 3000 to

16000 tubes each about 20 mmin diameter

Primary coolant outlet Primary coolant inlet

Anti-vibrationbars

Tubesupportplate

Tubesheet

IGA

SCC

Pitting

SCC

Inside Tubesheet

Top of Tubesheet

by SSHwang of KAERI

Denting

Sludge pile

in diameter

The SGT is made of nickel basedInconel alloy which is composed of 75 Ni 165Cr and 815Fe

-Degradation mechanism corrosion pitting denting inter granular attack

-Inspection Eddy current Testing(ECT)

Permeability Variation Clusters (PVC)

(Ferro-magnetic phase)

-005

000

005

010

015

m (emug)

1-1

-002

000

002

004

006

008

m (emug)

1-2

-1000 -500 0 500 1000

-015

-010

-005

H ( Am )

-1000 -500 0 500 1000

-006

-004

-002

H ( Am )

The hystresis loop in the fragment of PVC parts of Kori-1 retired SG tube

-004

-002

000

002

004

006

M (emug)

Inconel 600 tested at RT

under tensile stress

1 2 3

4 5 6

7 8 9-004

-002

000

002

004

006

M(emug)

Inconel 600 Heat treated at

602 oC under tensile stress

1 2 3

How can we detect magnetic phase

(PVC)selectively from the flaws in SGT

-3000 -2000 -1000 0 1000 2000 3000

-006

H (Oe)

7 8 9

10 11 12

-3000 -2000 -1000 0 1000 2000 3000

-006

-004

H(Oe)

4 5 6

7 8 9

The hysteresis loop of the tensile tested specimen at room temperature (a) and tensile tested at high temperature (b)

The magnetic phase can be created under the high temperature andpressure conditions which is correspond to the stress corrosion crackingin the SG tube in the NPP(Bruemmer SM Charlot LA amp Henager CH (1988) Corrosion 782)

Principle of ECT

If we can separate magnetic phase selectively from the

flaws using magnetic sensor the reliability of EC in SGT

inspection will be greatly enhanced

Structure of the permeability

sensor

Dimension and photograph of U-shape

sensing yoke

Design of Magnetic Sensor for PVC

sensor sensing yoke

Photograph of the completed sensor front side (above) and rear side (bottom)

R11R12

R10

R8

R6

R9

R13

R7

R14

C18

1 n

C17

C20

C21

D2

DIODE

SIN COS

-

+

U-2A

4

13

2

-

+

U-2B

75

6

8

-

+

U-3A

13

2

8

+5VC19

104

+5V

Schematic diagram of the sensor system

Electronic Circuit of Magnetic Sensor

R20

R

R21

R

-

+

U5AD797

3

26

74

U6

D1

S12

GND3

+VCC4VCC5

IN6

-VCC7

S28

C41

R13

R26

R18

R25

R2210 Ω

R16

R14

R17

10 k

R15

R27

R32

R28

R33

R29

R34

5 k

R30

C29

C37

104

C32473

C39473C40

104

C33

104

C21

104C23

104

C25

104

C26

104

C30

104

C31

104

C35

104

C36

104

C27

104

C28

104

C34

104

C38

104

D3

DIODE

L1

1

2

L2

1

2

L3

1

2

4

-

+

U-4A

4

13

2

-

+

U-4B

75

6

8

-

+

U-5A

4

13

2

-

+

U-5B

75

6

8

-

+

U-6A

4

13

2

-

+

U-6B

75

6

8

C22

104

-5V

+5V

+5V

+5V

+5V

+5V

+5V

U7

D1

S12

GND3

+VCC4

VCC5

IN6

-VCC7

S28

+5V

-5V

-5V

-5V

-5V

-5V

-5V

-5V

-5V

R19

R24

R

R23

R

C24

OUT(X)

OUT(Y)

R1

20 kR210 k

R3

20 kR410 k

C1

104

C8

104

REF43

OUT(X)

OUT(Y)

REF43

U2

+Vcc1

CH02

CH13

CH24

CH35

COMM6

SHDN7

Vref8

+Vcc9

GND10

GND11

DOUT12BUSY13DIN14CS15

DIN16

-

+

U-1A

13

2

8

-

+

U-1B

4

75

6

C410 uF

C5104

DOUT

C210uF

C6104

C3104

DCLK

C7104

DIN

C10

01uF

CS

BUSY

C14 10uF

J1

CON6

123456

D1

DIODE

R5

47K

C9

10uF

C1310uF

Y1

OSC

OUT3

GND2

VCC4

U3

RSTVPP1

GND10

VCC20

XTAL15

XTAL24

P10AIN012P11AIN113P1214P1315P1416P1517P1618P1719

P30RXD2

P31TXD3

P32INT06

P33INT17

P34T08

P35T19

P3711

U4

C1+1

C1-3

C2+4

C2-5

VCC16

GND15

V+2

V-6

R1OUT12

R2OUT9

T1IN11

T2IN10

R1IN13

R2IN8

T1OUT14

T2OUT7

C12 10uF

C16

01uF

C15 10uF

C11

01uF

-5V

+5V

+5V

+5V

+5V

+5V

+5V

+5V

RST

OSC

OSC

RST

DCLKCSDINBUSYDOUT

U1

IN2

GND

4

OUT6

TEMP3

TRIM5

-5V

+5V

Electronic circuit diagram of the magnetic sensor

Photograph of the completed measuring system data acquisition

software in PC and probe scanning system

Experimental Setup for Magnetic Sensor

Reference material Scanning System Software LabVIEW

Reference Material (1) Normal defects and PVCs

Longitudinal and transverse defects

Def W L D Remarks

1 02 500 0213 (20 ) Inner defects

2 02 500 0427 (40 )

3 02 500 0213 (20 )Outer defectsPVC(1018)4 02 500 0427 (40 )

5 02 500 0639 (60 )

6 02 500 0852 (80 )

7 02 500 0639 (60 ) Inner defects

8 02 500 0852 (80 )

- 1 and 2 are inner defects

- 345 and 6 are outer defects with PVC

- 7 and 8 are inner defects

PVC

PVC

Defect Defect

For longitudinal defects and PVC For circumferential defects and PVC

ECT is very difficult to detect circumferential defects

We can distinguish PVCs and defects and longitudinal and circumferential defects

Flux-gate Magnetometer

One core sensor Two core sensor

3-축 flux-gate Magnetometer의 계략도

Sensorpia Co

pro

cess

or(

AV

R)

Sensor 1

RS422

Interface

Mic

ro-p

roce

ssor(

AV

R)

Sensor 2

Sensor 3

Interface

조립된 마그네토미터의 사진

Sensorpia Co

Analog PCB

Digital PCB

Sensorpia Co선형도(linearity)

10

20

30

40

50

60

y-axis

Magnetometer Output (microT)

-60 -50 -40 -30 -20 -10 0 10 20 30 40 50 60

-60

-50

-40

-30

-20

-10

0

10

Y-axis y=099946 x+0015STD 106E-4

Magnetometer Output (

Applied Magnetic Field (microT)

마그네토미터의 noise 특성 Sensorpia Co

1

10

100

y-axis

Magnetometer noise (nT)

0 1 2 3 4 5 6

1E-4

1E-3

001

01

Magnetometer noise (nT)

Frequency (Hz)

Magnetometer for KoDSAT

-150 -100 -50 0 50 100 150

-15

-10

-5

0

5

10

15

Magnetic Moment (Am

2)

Current (mA)

After Thermal Cycle Test

Measured

Resistance 193 ohm

Photograph of Magnetic torquer

Photograph of KoDSAT

Photograph of

3-axis Fluxgate

Magnetometer

Photograph of Magnetic torquer

Application of magnetometer

Moon magnetic fieldmeasurement

Telescope with direction indication

Joule Effect (Magnetostriction)

ϕ2cosel

l=

∆

0=∆

+∆

+∆

b

b

a

a

l

l

Actuator using Terfenol-D

00

05

10

B (T)

800

1000

1200

1400

1600

Magnetostriction (ppm)

-100 -50 0 50 100

-10

-05

00

B (T)

H (kAm)

2 MPa

4 MPa

6 MPa

8 MPa

10 MPa

12 MPa

-100 -50 0 50 100

-200

0

200

400

600

Magnetostriction (ppm)

H (kAm)

2 MPa

4 MPa

6 MPa

8 MPa

10 MPa

12 MPa

600

700

800

900

1000

-4 -3 -2 -1 0 1 2 3 4

0

10

20

30

40

50

60

Displacement (m

icro meter)

I (A)

FIELD

9 kAm

12 kAm

16 kAm

20 kAm

24 kAm

38 kAm

-50 -40 -30 -20 -10 0 10 20 30 40 50

-100

0

100

200

300

400

500

L (PPM)

H (kAm)

9 kAm

12 kAm

16 kAm

20 kAm

24 kAm

38 kAm

Magnetostrictive displacement sensor

Hysteresis loops under

tensile stress σ

(a) Crystalline 68 NiFe

λs = +25 10-6

(b) crystalline pure Ni λs

= -35 10-6

Villari Effect ( Inverse of Joule Effect)

= -35 10-6

(c) amorphous Co-based

alloy

λs = -35 10-6

ϕσλ 2sin2

3sdotsdot= smeE

γ

Permeability depending on the stress

σλmicromicro

1

3

2

Y

J

so

s

r =

γ

Calculated magnetization curves under stress

Variation of magnetization curve by an applied

tensile force (Co-based amorphous alloy)

Alloy Requirement

Materials for magnetoelastic sensors

Why amorphous magnetic materials are important

Stress-strain curves of several materials

Coercivity and hardness of several materials

Principles of magnetoelastic sensors

Non-contact torque sensor

Principle of cross torductor torque

sensor and flux pattern of sensor

poles on the surface of a shaft

a) without and b)with torsional load

Equivalent magnetic circuit of

cross type torque sensor

Helices of principal tensile and compressive stress on the surface of

a shaft subjected to torsion [32] Correlated changes of permeability

are detected by four-branch yoke system with sensing coils 123

and 4 and a common excitation pole

Examples of torque sensors

Four-branch type torque sensor

heads Pole structures realized

by commercial multi-pole

ferrites 14 and 18 min in

diameter (diameter of sensor

h e a d 1 7 a n d 2 4 m m

respectively) respectively)

Principle of Ring Torductor torque transducer

(a b) Physical structure (c) evolution of the

shaft surface under the transducer poles A and BRing torductor for measuring

torque on ship propeller shafts

(shaft diameter ca 500 mm)

(Courtesy ASEA Brown

Boveri AG)

Principal designs of coaxial torque sensors

Schematic diagram of data processing

electronics of a torque sensor

Extensometer (a) Construction of strain sensing element using

amorphous ribbon wound core (b) configuration of lumped

windings

∆E effect of an amorphous FeNi-based

alloy (Fe40 Ni38 Mo4 B18) Hs saturation

field

Magnetically tunable delay line

Torque Sensors using Amorphous wire

Sixtus tonk효과(large Barkhausen효과)

Hysteresis loops of a Wiegand wire for different reset fields

Curie 온도 및Hopkinson효과

Relation between normalised

saturation polarisation and

normalised Curie temperature

Permeability of a Mn-Zn ferrite as

a function of temperature and field

strength

Conclusions

1) Magnetic sensor 는 자동차 공장자동화 항공우주 및 군사용으로많이 사용되고 있다

2) 새로운 소재개발은 자기센서의 성능개발에 직접적인 영향을 준다2) 새로운 소재개발은 자기센서의 성능개발에 직접적인 영향을 준다

3) 센서의 개발을 위해서는 다양한 전공지식이 요구된다

(물리학 재료공학 기계공학 전자공학)

4) 센서분야가 고부가가치를 창출하는 부품사업이다

5) 핵심부품을 생산하는 중소기업의 item으로도 적절하다

( ) 1

370

ndc

DwC r

sdotminussdotsdotsdot

=ε

1

i

2tot minus+=k

C

k

CC

Capacitance C of a coil

Capacitance C of a single-layer coil normalized to

its diameter D versus length-to-diameter ratio wD

of the coil (capacitance C in pF and geometrical

dimensions w and D in cm)

12 minuskk

High permeability core induction coil

Magnetic field pattern around high permeability core

when it is inserted into a homogeneous field It is valid

for low frequencies and if the coil indicated at the middle

of the core is without current

Magnetization of a high permeability core

dt

dnu ci

i Φ

sdotminus= ) ( cosmaxc ci tωsdotΦ=Φ

ci0rc0 maxAHnnU sdotsdotsdotsdot=Φsdotsdot= micromicroωω

HNHHHH )1( minusminus=+= micro

HN

H sdotminus+

=)1(1

1

r

i micro

irdmi HNHHHH )1( minusminus=+= micro

HfAnU sdotsdotsdotsdotsdotsdot= 0cc0 2 micromicroπ

)1(1 r

rc minus+=

micromicro

microN

minus++

minusminus=

infin1)1ln(

11

1 2

22ell mmm

m

mN

10326) (1ln 152

10156) (1ln 262

ell

cyl

++++

=infin

infin

N

N

Induction coil on a cylindrical high permeability core

Demagnetization factorDemagnetization factorN of prolate ellipsoidsand cylindrical rods(descending curves) andcore permeability μc

(ascending curves) ofcylindrical rods versusthe length-to-diameterratio m of the rod withmaterial permeability μr

as parameter

Core permeability μc of cylindrical rods versus thematerial permeability μr with length-to-diameter ratiom of the rod as parameter after

Minimum noise equivalent magnetic field spectral density of an induction coil sensor with high permeability core versus sensor weight Ws (at length-to-diameter ratios m = 50 and 100 permeability μr = 10000 of the core material and f = 1 Hz)

Induction coil sensors with electronic amplifier

II

rKLC

1=ω

II

II

RR

RK

+=

rr

2 i 1

)(

ωω

ωω

ω

D

KF

+

minus

=

+=

II

II

II

2

C

L

R

R

C

L

KD

Frequency responses of the search coil

Frequency responses of thesensitivity SA and the output voltage UA

of an induction coil sensor with a voltageamplifier at a constant magnetic fieldamplitude

Resonance step-up of thesensitivity SA at differentvalues of the damping D

Sensor with transformer coupled negative feedback to the coil

)(i)()(F

0 ωωωω FR

UMUAU A

A sdot

minus=

)( i1

)(

F

0

ωω

ω

FR

MA

FAUU A

sdot+

sdot=

Induction coil connected to a voltage amplifier with

transformer coupled negative feedback to the coil

FR

21

1K0

i1

1

i1

i )(

ωωωωωω

ωω

+sdot

+sdot=

M

RUU A

IIF2 CRL

MAf

sdotsdotsdotsdot

=∆π

Frequency response of the output voltage UA of an induction coil sensor with negative feedback transformer coupled to the coil

Applications of search coil magnetometer

Developed search coil magnetometer using amorphous ribbon

Experimental setup for the effective permeability measurement

Relative permeability depending on the numbers of ribbon(a)

and the air gap between ribbons

Relative permeability depending on the number of ribbons for the different air gap between ribbons

Relative permeability depending on the total number of ribbons for the different air gap between ribbons

10 pT

100 pT

1 pT

Noise spectrum of the developed search coil magnetometer

BJne

E xH

1minus=

neRH

1minus=

22 nP micromicro minus

Hall 효과

Bt

IRU H

HL =

2

22

)( he

eh

Hpne

nPR

micromicromicromicro

+

minus=

Rectangular Hall plate (cc1cc2 current constant sc1sc2

sensor constant I bias current U voltage drop UH Hall

voltage

Physics carrier concentration and kind of carrier measurement

Engineering magnetic field measurement

Current Measurement

Arrangement for noninvasive

current measurement using an iron

core The current to be measured

produces a proportional magnetic

field which can be measured in the

air gap

Characteristic curve produced by

the current

Arrangement for indirect noninvasive

current measurement using the

compensation principle An iron core as

represented in Figure 3-29 is held field

free by injection a current into a

compensating coil wound on the core

which offsets the field generated by the

current being measured The Hall effect

sensor in the air gap serves as a null

indicator

Circuit diagram for AC-power

measurement using a Hall effect

sensor

DC Power Measurement

Circuit diagram for DC-

power measurement using a

Hall effect sensor

Noncontact Position Sensing

Galvanomagnetic components for sensing the position of permanent magnets

and magnetically conductive materials

Current Sensor Based on Hall Sensor

and Magnetic Core for Hybrid Vehicle

KH Yeon1 SD Kim1 and D Son2 1Auto industry co14F Hanshin IT tower Guro Gu Seoul Korea2Hannam UniversityOjung dong 133 Daejeon Rep of Korea

i

Hall sensor

B

I

SB

ring core

B

I10

g

N

Bl S

micro

)( gtgtrmicro

gab core

Current Sensor Based on Hall

Sensor and Magnetic Core

Hall

Effect

Device

CurrentVoltage

applying for

Hall effect device

operation

Output

signals

Magnetic field

Occurred by

current measurement

Signal

process

circuits

Developed Current Sensor

Magnetic core

Hall sensor

PCB

25

30

35

40

45

50

Output voltage V

Current sensor(Open loop type)

Temp 25C

400A model

+400 ~ -400A

SD 000128

Linearity 003

Linearity of the sensor

Characteristics of the Current Sensors

1000A 10 V power supply

-500 -400 -300 -200 -100 0 100 200 300 400 500

00

05

10

15

20

Output voltage V

current A

Temperature 25Linearity 003

Measuring range -400A ~ +400A

1000A Electronic Load

-3

0

3

6

9

12

15

18

dB

Current sensor

DV2 PCB 24pF

40Aturns

Frequency bandwidth

Gain bandwidth 3 MHz

Current 10 A

Temperature 25

Frequency bandwidth 100 kHz

Sensor output voltage vs frequency

at applied current of 40 Aturns

1 10 100

-18

-15

-12

-9

-6

Frequency kHz 측정온도 25

주파수특성 30kHz 이상(3dB 기준)

측정전류 40Aturns(4A 10턴)

측정주파수 100Hz ~ 100kHz

Temperature 25Current 40Aturns

Frequency range 100 Hz ~ 100 kHz

What is Magnetoresistance

Magnetoresistance effect(AMR)

θθθ 2cos2

12sin12cos(

22 minusminus+∆asymp∆ xxxmx hhhRR

32 minusasymp∆ ρρ New effect GMR CMR and GMI

10 ge∆ ρρ

Two bridge configuration for

rotational angle measurement

measurement angle more than 180o

자동차 Engine Management System

Inductive and Eddy Current

Sensors Excited by Permanent Magnets

tNtU dd)( φsdotminus=

construction of an inductive

sensor (courtesy VDO Adolf sensor (courtesy VDO Adolf

Schindling AG)

1) constant socket

2) terminal package

3) permanent magnet

4) cap

5) soft magnetic core

6) coil

7) plate

8) blade connector

γγ

Sensor with yoke Change in the magnetic flux with

varying air gap Continuous lines

minimum air gap dashed lines

maximum air gap

C-shaped sensor

Sensor with radially

magnetized

permanent magnet

Signal Conditioning

Output voltage U of a DC-excited sensor with permanent

magnets when a single iron object passes by

Schematic electrical diagram of an inductive sensor

Linear Variable Differential Transformer

AC-Excited Sensors for Linear Movement

Principle of construction of an LVDT

Electrical circuit of an LVDT

tIMtNU dd dd sdotminus=sdotminus= φ

tIMtIMUUU dd dd 1212 sdotminussdot=minus=

tIMMU dd)( 12 sdotminus=

)(12 xMMMM =minus=

tIxMU dd)( sdot= tI

UxM

dd)( =

Signal Conditioning

power supply

carrier gen

autoampcontrol

LVDTcarrieramp

demod-ulator

phase

shifter

power supply

carrier gen

passivedemod-ulator

LVDTDCamp

Block diagram of a carrier amplifier system

Block diagram of a DC amplifier system

Variable Inductive Sensors

Principle of construction

of the VLP sensor

Principle of a bridge

circuit

lANL r 20 sdotsdotsdot= micromicro

21 BA UUU minus=

21)i(ii( 211 minus+sdot= LLLUU BA ωωω

)21))()((( minus∆minus+∆+∆+sdot= LLLLLLUU BA

)212)(( minus∆+sdot= LLLUU )212)(( minus∆+sdot= LLLUU BA

LLUU BA 21 ∆sdotsdot=

llLL ∆sdot=∆ d d

llLLUU BA ∆sdotsdot= d d)2(1

Applications and Properties

Principle of a construction of a force transducer

(courtesy Hottinger Baldwin Messtechnik)

Vibrationacceleration sensor

Signal Conditioning

Schematic electrical diagram of a force transducer connected with an

amplifier (courtesy Hottinger Baldwin Messtechnik GmbH)

Variable Gap Sensors

)( FeFe2

0 LLllANL micromicromicro +sdotsdot=

FeFe2

0max lANL sdotsdotsdot= micromicro

Construction of a variable gap sensor

Characteristic of a variable gap sensor

Construction of a differential

cross-anchor sensor

Output voltage U versus core

position x plusmn a limits of the

linear rage

Applications of differential cross-anchor sensors

AC-excited Sensors for Rotary Movements

Principle of construction of a synchro

α cos10 sdotsdot= UKU y

)120-( cos10 degsdotsdot= αUKU z

)240-( cos10 degsdotsdot= αUKU x

)120-( sin3100 degsdotsdotsdot=minus= αKUUUU yxyx

)240-( sin3100 degsdotsdotsdot=minus= αKUUUU zyzy

α sin3100 sdotsdotsdot=minus= KUUUU xzxz

Application to the Torque Sensor

Principle of construction of a torque-type synchro

Torque versus angular

difference

)( sin~ rt αα minussdotKM

)( cos~ rt1r αα minussdotUU

Principle of construction of a control-type sensor

Output voltage versus

angular difference

Principle of construction of a differential sychro

Eddy Current Sensors

tBE dd curl minus=JH = curl

0 div =BH(H)B sdot= micro

E(E)J sdot= σ

A B curl= A B curl=

tdd- A E =

)dd( tAJ minus= σ

tdd curl curl AA σmicro minus=

AA) σωmicro iminus= curl )(curl(1

AA) σωmicro i=∆)((1

Eddy Current Tachometer

Construction of a speedometer (courtesy VDO Adolf Schinding AG) 1) spindle 2) bearing

3) holding spring 4) iron yoke 5) eddy current cup 6) shaft of the magnet 7) support of

the magnet 8) temperature compensation 9) permanent magnet 10) torsion spring

Proximity Sensors

Schematic diagram of a proximity sensor

Output current of a proximity switch versus distance

Inductive Flowmeters

)( Btimessdot= υqF

EqF sdot=BE times=υ

)(ds Btimes== υEU )(ds Btimes== υEU

)( Bd timessdot= υU

Bsdotsdotsdot= υdKU

Development of magnetic phase detection

sensor for steam generator tube

Dirac Son1 Kwan-Sang Ryu2 Duck-Gun Park3

1Hannam University Daejeon Rep of Korea2Korea Research Institute of Standards and Science Daejeon Rep of Korea3KoreaAtomic Energy Research Institute Daejeon Rep of Korea

Introduction

The layout of pressurized water reactor (PWR) components

Primary side Secondary side (non-radioactive side)(radioactive side)

The Structure of SG(Steam Generator)(degradation mechanism)

Secondary SidePrimary Side

SCC

A B

A-B

Steam outlet

Anti-vibration

SCC

Fretting

Wall thinning

IGA

U-bend

In commercial power plants SG- height up to 21 m - weight up to 800 tons - 2~4 sets of SG were installed - SG can contain from 3000 to

16000 tubes each about 20 mmin diameter

Primary coolant outlet Primary coolant inlet

Anti-vibrationbars

Tubesupportplate

Tubesheet

IGA

SCC

Pitting

SCC

Inside Tubesheet

Top of Tubesheet

by SSHwang of KAERI

Denting

Sludge pile

in diameter

The SGT is made of nickel basedInconel alloy which is composed of 75 Ni 165Cr and 815Fe

-Degradation mechanism corrosion pitting denting inter granular attack

-Inspection Eddy current Testing(ECT)

Permeability Variation Clusters (PVC)

(Ferro-magnetic phase)

-005

000

005

010

015

m (emug)

1-1

-002

000

002

004

006

008

m (emug)

1-2

-1000 -500 0 500 1000

-015

-010

-005

H ( Am )

-1000 -500 0 500 1000

-006

-004

-002

H ( Am )

The hystresis loop in the fragment of PVC parts of Kori-1 retired SG tube

-004

-002

000

002

004

006

M (emug)

Inconel 600 tested at RT

under tensile stress

1 2 3

4 5 6

7 8 9-004

-002

000

002

004

006

M(emug)

Inconel 600 Heat treated at

602 oC under tensile stress

1 2 3

How can we detect magnetic phase

(PVC)selectively from the flaws in SGT

-3000 -2000 -1000 0 1000 2000 3000

-006

H (Oe)

7 8 9

10 11 12

-3000 -2000 -1000 0 1000 2000 3000

-006

-004

H(Oe)

4 5 6

7 8 9

The hysteresis loop of the tensile tested specimen at room temperature (a) and tensile tested at high temperature (b)

The magnetic phase can be created under the high temperature andpressure conditions which is correspond to the stress corrosion crackingin the SG tube in the NPP(Bruemmer SM Charlot LA amp Henager CH (1988) Corrosion 782)

Principle of ECT

If we can separate magnetic phase selectively from the

flaws using magnetic sensor the reliability of EC in SGT

inspection will be greatly enhanced

Structure of the permeability

sensor

Dimension and photograph of U-shape

sensing yoke

Design of Magnetic Sensor for PVC

sensor sensing yoke

Photograph of the completed sensor front side (above) and rear side (bottom)

R11R12

R10

R8

R6

R9

R13

R7

R14

C18

1 n

C17

C20

C21

D2

DIODE

SIN COS

-

+

U-2A

4

13

2

-

+

U-2B

75

6

8

-

+

U-3A

13

2

8

+5VC19

104

+5V

Schematic diagram of the sensor system

Electronic Circuit of Magnetic Sensor

R20

R

R21

R

-

+

U5AD797

3

26

74

U6

D1

S12

GND3

+VCC4VCC5

IN6

-VCC7

S28

C41

R13

R26

R18

R25

R2210 Ω

R16

R14

R17

10 k

R15

R27

R32

R28

R33

R29

R34

5 k

R30

C29

C37

104

C32473

C39473C40

104

C33

104

C21

104C23

104

C25

104

C26

104

C30

104

C31

104

C35

104

C36

104

C27

104

C28

104

C34

104

C38

104

D3

DIODE

L1

1

2

L2

1

2

L3

1

2

4

-

+

U-4A

4

13

2

-

+

U-4B

75

6

8

-

+

U-5A

4

13

2

-

+

U-5B

75

6

8

-

+

U-6A

4

13

2

-

+

U-6B

75

6

8

C22

104

-5V

+5V

+5V

+5V

+5V

+5V

+5V

U7

D1

S12

GND3

+VCC4

VCC5

IN6

-VCC7

S28

+5V

-5V

-5V

-5V

-5V

-5V

-5V

-5V

-5V

R19

R24

R

R23

R

C24

OUT(X)

OUT(Y)

R1

20 kR210 k

R3

20 kR410 k

C1

104

C8

104

REF43

OUT(X)

OUT(Y)

REF43

U2

+Vcc1

CH02

CH13

CH24

CH35

COMM6

SHDN7

Vref8

+Vcc9

GND10

GND11

DOUT12BUSY13DIN14CS15

DIN16

-

+

U-1A

13

2

8

-

+

U-1B

4

75

6

C410 uF

C5104

DOUT

C210uF

C6104

C3104

DCLK

C7104

DIN

C10

01uF

CS

BUSY

C14 10uF

J1

CON6

123456

D1

DIODE

R5

47K

C9

10uF

C1310uF

Y1

OSC

OUT3

GND2

VCC4

U3

RSTVPP1

GND10

VCC20

XTAL15

XTAL24

P10AIN012P11AIN113P1214P1315P1416P1517P1618P1719

P30RXD2

P31TXD3

P32INT06

P33INT17

P34T08

P35T19

P3711

U4

C1+1

C1-3

C2+4

C2-5

VCC16

GND15

V+2

V-6

R1OUT12

R2OUT9

T1IN11

T2IN10

R1IN13

R2IN8

T1OUT14

T2OUT7

C12 10uF

C16

01uF

C15 10uF

C11

01uF

-5V

+5V

+5V

+5V

+5V

+5V

+5V

+5V

RST

OSC

OSC

RST

DCLKCSDINBUSYDOUT

U1

IN2

GND

4

OUT6

TEMP3

TRIM5

-5V

+5V

Electronic circuit diagram of the magnetic sensor

Photograph of the completed measuring system data acquisition

software in PC and probe scanning system

Experimental Setup for Magnetic Sensor

Reference material Scanning System Software LabVIEW

Reference Material (1) Normal defects and PVCs

Longitudinal and transverse defects

Def W L D Remarks

1 02 500 0213 (20 ) Inner defects

2 02 500 0427 (40 )

3 02 500 0213 (20 )Outer defectsPVC(1018)4 02 500 0427 (40 )

5 02 500 0639 (60 )

6 02 500 0852 (80 )

7 02 500 0639 (60 ) Inner defects

8 02 500 0852 (80 )

- 1 and 2 are inner defects

- 345 and 6 are outer defects with PVC

- 7 and 8 are inner defects

PVC

PVC

Defect Defect

For longitudinal defects and PVC For circumferential defects and PVC

ECT is very difficult to detect circumferential defects

We can distinguish PVCs and defects and longitudinal and circumferential defects

Flux-gate Magnetometer

One core sensor Two core sensor

3-축 flux-gate Magnetometer의 계략도

Sensorpia Co

pro

cess

or(

AV

R)

Sensor 1

RS422

Interface

Mic

ro-p

roce

ssor(

AV

R)

Sensor 2

Sensor 3

Interface

조립된 마그네토미터의 사진

Sensorpia Co

Analog PCB

Digital PCB

Sensorpia Co선형도(linearity)

10

20

30

40

50

60

y-axis

Magnetometer Output (microT)

-60 -50 -40 -30 -20 -10 0 10 20 30 40 50 60

-60

-50

-40

-30

-20

-10

0

10

Y-axis y=099946 x+0015STD 106E-4

Magnetometer Output (

Applied Magnetic Field (microT)

마그네토미터의 noise 특성 Sensorpia Co

1

10

100

y-axis

Magnetometer noise (nT)

0 1 2 3 4 5 6

1E-4

1E-3

001

01

Magnetometer noise (nT)

Frequency (Hz)

Magnetometer for KoDSAT

-150 -100 -50 0 50 100 150

-15

-10

-5

0

5

10

15

Magnetic Moment (Am

2)

Current (mA)

After Thermal Cycle Test

Measured

Resistance 193 ohm

Photograph of Magnetic torquer

Photograph of KoDSAT

Photograph of

3-axis Fluxgate

Magnetometer

Photograph of Magnetic torquer

Application of magnetometer

Moon magnetic fieldmeasurement

Telescope with direction indication

Joule Effect (Magnetostriction)

ϕ2cosel

l=

∆

0=∆

+∆

+∆

b

b

a

a

l

l

Actuator using Terfenol-D

00

05

10

B (T)

800

1000

1200

1400

1600

Magnetostriction (ppm)

-100 -50 0 50 100

-10

-05

00

B (T)

H (kAm)

2 MPa

4 MPa

6 MPa

8 MPa

10 MPa

12 MPa

-100 -50 0 50 100

-200

0

200

400

600

Magnetostriction (ppm)

H (kAm)

2 MPa

4 MPa

6 MPa

8 MPa

10 MPa

12 MPa

600

700

800

900

1000

-4 -3 -2 -1 0 1 2 3 4

0

10

20

30

40

50

60

Displacement (m

icro meter)

I (A)

FIELD

9 kAm

12 kAm

16 kAm

20 kAm

24 kAm

38 kAm

-50 -40 -30 -20 -10 0 10 20 30 40 50

-100

0

100

200

300

400

500

L (PPM)

H (kAm)

9 kAm

12 kAm

16 kAm

20 kAm

24 kAm

38 kAm

Magnetostrictive displacement sensor

Hysteresis loops under

tensile stress σ

(a) Crystalline 68 NiFe

λs = +25 10-6

(b) crystalline pure Ni λs

= -35 10-6

Villari Effect ( Inverse of Joule Effect)

= -35 10-6

(c) amorphous Co-based

alloy

λs = -35 10-6

ϕσλ 2sin2

3sdotsdot= smeE

γ

Permeability depending on the stress

σλmicromicro

1

3

2

Y

J

so

s

r =

γ

Calculated magnetization curves under stress

Variation of magnetization curve by an applied

tensile force (Co-based amorphous alloy)

Alloy Requirement

Materials for magnetoelastic sensors

Why amorphous magnetic materials are important

Stress-strain curves of several materials

Coercivity and hardness of several materials

Principles of magnetoelastic sensors

Non-contact torque sensor

Principle of cross torductor torque

sensor and flux pattern of sensor

poles on the surface of a shaft

a) without and b)with torsional load

Equivalent magnetic circuit of

cross type torque sensor

Helices of principal tensile and compressive stress on the surface of

a shaft subjected to torsion [32] Correlated changes of permeability

are detected by four-branch yoke system with sensing coils 123

and 4 and a common excitation pole

Examples of torque sensors

Four-branch type torque sensor

heads Pole structures realized

by commercial multi-pole

ferrites 14 and 18 min in

diameter (diameter of sensor

h e a d 1 7 a n d 2 4 m m

respectively) respectively)

Principle of Ring Torductor torque transducer

(a b) Physical structure (c) evolution of the

shaft surface under the transducer poles A and BRing torductor for measuring

torque on ship propeller shafts

(shaft diameter ca 500 mm)

(Courtesy ASEA Brown

Boveri AG)

Principal designs of coaxial torque sensors

Schematic diagram of data processing

electronics of a torque sensor

Extensometer (a) Construction of strain sensing element using

amorphous ribbon wound core (b) configuration of lumped

windings

∆E effect of an amorphous FeNi-based

alloy (Fe40 Ni38 Mo4 B18) Hs saturation

field

Magnetically tunable delay line

Torque Sensors using Amorphous wire

Sixtus tonk효과(large Barkhausen효과)

Hysteresis loops of a Wiegand wire for different reset fields

Curie 온도 및Hopkinson효과

Relation between normalised

saturation polarisation and

normalised Curie temperature

Permeability of a Mn-Zn ferrite as

a function of temperature and field

strength

Conclusions

1) Magnetic sensor 는 자동차 공장자동화 항공우주 및 군사용으로많이 사용되고 있다

2) 새로운 소재개발은 자기센서의 성능개발에 직접적인 영향을 준다2) 새로운 소재개발은 자기센서의 성능개발에 직접적인 영향을 준다

3) 센서의 개발을 위해서는 다양한 전공지식이 요구된다

(물리학 재료공학 기계공학 전자공학)

4) 센서분야가 고부가가치를 창출하는 부품사업이다

5) 핵심부품을 생산하는 중소기업의 item으로도 적절하다

High permeability core induction coil

Magnetic field pattern around high permeability core

when it is inserted into a homogeneous field It is valid

for low frequencies and if the coil indicated at the middle

of the core is without current

Magnetization of a high permeability core

dt

dnu ci

i Φ

sdotminus= ) ( cosmaxc ci tωsdotΦ=Φ

ci0rc0 maxAHnnU sdotsdotsdotsdot=Φsdotsdot= micromicroωω

HNHHHH )1( minusminus=+= micro

HN

H sdotminus+

=)1(1

1

r

i micro

irdmi HNHHHH )1( minusminus=+= micro

HfAnU sdotsdotsdotsdotsdotsdot= 0cc0 2 micromicroπ

)1(1 r

rc minus+=

micromicro

microN

minus++

minusminus=

infin1)1ln(

11

1 2

22ell mmm

m

mN

10326) (1ln 152

10156) (1ln 262

ell

cyl

++++

=infin

infin

N

N

Induction coil on a cylindrical high permeability core

Demagnetization factorDemagnetization factorN of prolate ellipsoidsand cylindrical rods(descending curves) andcore permeability μc

(ascending curves) ofcylindrical rods versusthe length-to-diameterratio m of the rod withmaterial permeability μr

as parameter

Core permeability μc of cylindrical rods versus thematerial permeability μr with length-to-diameter ratiom of the rod as parameter after

Minimum noise equivalent magnetic field spectral density of an induction coil sensor with high permeability core versus sensor weight Ws (at length-to-diameter ratios m = 50 and 100 permeability μr = 10000 of the core material and f = 1 Hz)

Induction coil sensors with electronic amplifier

II

rKLC

1=ω

II

II

RR

RK

+=

rr

2 i 1

)(

ωω

ωω

ω

D

KF

+

minus

=

+=

II

II

II

2

C

L

R

R

C

L

KD

Frequency responses of the search coil

Frequency responses of thesensitivity SA and the output voltage UA

of an induction coil sensor with a voltageamplifier at a constant magnetic fieldamplitude

Resonance step-up of thesensitivity SA at differentvalues of the damping D

Sensor with transformer coupled negative feedback to the coil

)(i)()(F

0 ωωωω FR

UMUAU A

A sdot

minus=

)( i1

)(

F

0

ωω

ω

FR

MA

FAUU A

sdot+

sdot=

Induction coil connected to a voltage amplifier with

transformer coupled negative feedback to the coil

FR

21

1K0

i1

1

i1

i )(

ωωωωωω

ωω

+sdot

+sdot=

M

RUU A

IIF2 CRL

MAf

sdotsdotsdotsdot

=∆π

Frequency response of the output voltage UA of an induction coil sensor with negative feedback transformer coupled to the coil

Applications of search coil magnetometer

Developed search coil magnetometer using amorphous ribbon

Experimental setup for the effective permeability measurement

Relative permeability depending on the numbers of ribbon(a)

and the air gap between ribbons

Relative permeability depending on the number of ribbons for the different air gap between ribbons

Relative permeability depending on the total number of ribbons for the different air gap between ribbons

10 pT

100 pT

1 pT

Noise spectrum of the developed search coil magnetometer

BJne

E xH

1minus=

neRH

1minus=

22 nP micromicro minus

Hall 효과

Bt

IRU H

HL =

2

22

)( he

eh

Hpne

nPR

micromicromicromicro

+

minus=

Rectangular Hall plate (cc1cc2 current constant sc1sc2

sensor constant I bias current U voltage drop UH Hall

voltage

Physics carrier concentration and kind of carrier measurement

Engineering magnetic field measurement

Current Measurement

Arrangement for noninvasive

current measurement using an iron

core The current to be measured

produces a proportional magnetic

field which can be measured in the

air gap

Characteristic curve produced by

the current

Arrangement for indirect noninvasive

current measurement using the

compensation principle An iron core as

represented in Figure 3-29 is held field

free by injection a current into a

compensating coil wound on the core

which offsets the field generated by the

current being measured The Hall effect

sensor in the air gap serves as a null

indicator

Circuit diagram for AC-power

measurement using a Hall effect

sensor

DC Power Measurement

Circuit diagram for DC-

power measurement using a

Hall effect sensor

Noncontact Position Sensing

Galvanomagnetic components for sensing the position of permanent magnets

and magnetically conductive materials

Current Sensor Based on Hall Sensor

and Magnetic Core for Hybrid Vehicle

KH Yeon1 SD Kim1 and D Son2 1Auto industry co14F Hanshin IT tower Guro Gu Seoul Korea2Hannam UniversityOjung dong 133 Daejeon Rep of Korea

i

Hall sensor

B

I

SB

ring core

B

I10

g

N

Bl S

micro

)( gtgtrmicro

gab core

Current Sensor Based on Hall

Sensor and Magnetic Core

Hall

Effect

Device

CurrentVoltage

applying for

Hall effect device

operation

Output

signals

Magnetic field

Occurred by

current measurement

Signal

process

circuits

Developed Current Sensor

Magnetic core

Hall sensor

PCB

25

30

35

40

45

50

Output voltage V

Current sensor(Open loop type)

Temp 25C

400A model

+400 ~ -400A

SD 000128

Linearity 003

Linearity of the sensor

Characteristics of the Current Sensors

1000A 10 V power supply

-500 -400 -300 -200 -100 0 100 200 300 400 500

00

05

10

15

20

Output voltage V

current A

Temperature 25Linearity 003

Measuring range -400A ~ +400A

1000A Electronic Load

-3

0

3

6

9

12

15

18

dB

Current sensor

DV2 PCB 24pF

40Aturns

Frequency bandwidth

Gain bandwidth 3 MHz

Current 10 A

Temperature 25

Frequency bandwidth 100 kHz

Sensor output voltage vs frequency

at applied current of 40 Aturns

1 10 100

-18

-15

-12

-9

-6

Frequency kHz 측정온도 25

주파수특성 30kHz 이상(3dB 기준)

측정전류 40Aturns(4A 10턴)

측정주파수 100Hz ~ 100kHz

Temperature 25Current 40Aturns

Frequency range 100 Hz ~ 100 kHz

What is Magnetoresistance

Magnetoresistance effect(AMR)

θθθ 2cos2

12sin12cos(

22 minusminus+∆asymp∆ xxxmx hhhRR

32 minusasymp∆ ρρ New effect GMR CMR and GMI

10 ge∆ ρρ

Two bridge configuration for

rotational angle measurement

measurement angle more than 180o

자동차 Engine Management System

Inductive and Eddy Current

Sensors Excited by Permanent Magnets

tNtU dd)( φsdotminus=

construction of an inductive

sensor (courtesy VDO Adolf sensor (courtesy VDO Adolf

Schindling AG)

1) constant socket

2) terminal package

3) permanent magnet

4) cap

5) soft magnetic core

6) coil

7) plate

8) blade connector

γγ

Sensor with yoke Change in the magnetic flux with

varying air gap Continuous lines

minimum air gap dashed lines

maximum air gap

C-shaped sensor

Sensor with radially

magnetized

permanent magnet

Signal Conditioning

Output voltage U of a DC-excited sensor with permanent

magnets when a single iron object passes by

Schematic electrical diagram of an inductive sensor

Linear Variable Differential Transformer

AC-Excited Sensors for Linear Movement

Principle of construction of an LVDT

Electrical circuit of an LVDT

tIMtNU dd dd sdotminus=sdotminus= φ

tIMtIMUUU dd dd 1212 sdotminussdot=minus=

tIMMU dd)( 12 sdotminus=

)(12 xMMMM =minus=

tIxMU dd)( sdot= tI

UxM

dd)( =

Signal Conditioning

power supply

carrier gen

autoampcontrol

LVDTcarrieramp

demod-ulator

phase

shifter

power supply

carrier gen

passivedemod-ulator

LVDTDCamp

Block diagram of a carrier amplifier system

Block diagram of a DC amplifier system

Variable Inductive Sensors

Principle of construction

of the VLP sensor

Principle of a bridge

circuit

lANL r 20 sdotsdotsdot= micromicro

21 BA UUU minus=

21)i(ii( 211 minus+sdot= LLLUU BA ωωω

)21))()((( minus∆minus+∆+∆+sdot= LLLLLLUU BA

)212)(( minus∆+sdot= LLLUU )212)(( minus∆+sdot= LLLUU BA

LLUU BA 21 ∆sdotsdot=

llLL ∆sdot=∆ d d

llLLUU BA ∆sdotsdot= d d)2(1

Applications and Properties

Principle of a construction of a force transducer

(courtesy Hottinger Baldwin Messtechnik)

Vibrationacceleration sensor

Signal Conditioning

Schematic electrical diagram of a force transducer connected with an

amplifier (courtesy Hottinger Baldwin Messtechnik GmbH)

Variable Gap Sensors

)( FeFe2

0 LLllANL micromicromicro +sdotsdot=

FeFe2

0max lANL sdotsdotsdot= micromicro

Construction of a variable gap sensor

Characteristic of a variable gap sensor

Construction of a differential

cross-anchor sensor

Output voltage U versus core

position x plusmn a limits of the

linear rage

Applications of differential cross-anchor sensors

AC-excited Sensors for Rotary Movements

Principle of construction of a synchro

α cos10 sdotsdot= UKU y

)120-( cos10 degsdotsdot= αUKU z

)240-( cos10 degsdotsdot= αUKU x

)120-( sin3100 degsdotsdotsdot=minus= αKUUUU yxyx

)240-( sin3100 degsdotsdotsdot=minus= αKUUUU zyzy

α sin3100 sdotsdotsdot=minus= KUUUU xzxz

Application to the Torque Sensor

Principle of construction of a torque-type synchro

Torque versus angular

difference

)( sin~ rt αα minussdotKM

)( cos~ rt1r αα minussdotUU

Principle of construction of a control-type sensor

Output voltage versus

angular difference

Principle of construction of a differential sychro

Eddy Current Sensors

tBE dd curl minus=JH = curl

0 div =BH(H)B sdot= micro

E(E)J sdot= σ

A B curl= A B curl=

tdd- A E =

)dd( tAJ minus= σ

tdd curl curl AA σmicro minus=

AA) σωmicro iminus= curl )(curl(1

AA) σωmicro i=∆)((1

Eddy Current Tachometer

Construction of a speedometer (courtesy VDO Adolf Schinding AG) 1) spindle 2) bearing

3) holding spring 4) iron yoke 5) eddy current cup 6) shaft of the magnet 7) support of

the magnet 8) temperature compensation 9) permanent magnet 10) torsion spring

Proximity Sensors

Schematic diagram of a proximity sensor

Output current of a proximity switch versus distance

Inductive Flowmeters

)( Btimessdot= υqF

EqF sdot=BE times=υ

)(ds Btimes== υEU )(ds Btimes== υEU

)( Bd timessdot= υU

Bsdotsdotsdot= υdKU

Development of magnetic phase detection

sensor for steam generator tube

Dirac Son1 Kwan-Sang Ryu2 Duck-Gun Park3

1Hannam University Daejeon Rep of Korea2Korea Research Institute of Standards and Science Daejeon Rep of Korea3KoreaAtomic Energy Research Institute Daejeon Rep of Korea

Introduction

The layout of pressurized water reactor (PWR) components

Primary side Secondary side (non-radioactive side)(radioactive side)

The Structure of SG(Steam Generator)(degradation mechanism)

Secondary SidePrimary Side

SCC

A B

A-B

Steam outlet

Anti-vibration

SCC

Fretting

Wall thinning

IGA

U-bend

In commercial power plants SG- height up to 21 m - weight up to 800 tons - 2~4 sets of SG were installed - SG can contain from 3000 to

16000 tubes each about 20 mmin diameter

Primary coolant outlet Primary coolant inlet

Anti-vibrationbars

Tubesupportplate

Tubesheet

IGA

SCC

Pitting

SCC

Inside Tubesheet

Top of Tubesheet

by SSHwang of KAERI

Denting

Sludge pile

in diameter

The SGT is made of nickel basedInconel alloy which is composed of 75 Ni 165Cr and 815Fe

-Degradation mechanism corrosion pitting denting inter granular attack

-Inspection Eddy current Testing(ECT)

Permeability Variation Clusters (PVC)

(Ferro-magnetic phase)

-005

000

005

010

015

m (emug)

1-1

-002

000

002

004

006

008

m (emug)

1-2

-1000 -500 0 500 1000

-015

-010

-005

H ( Am )

-1000 -500 0 500 1000

-006

-004

-002

H ( Am )

The hystresis loop in the fragment of PVC parts of Kori-1 retired SG tube

-004

-002

000

002

004

006

M (emug)

Inconel 600 tested at RT

under tensile stress

1 2 3

4 5 6

7 8 9-004

-002

000

002

004

006

M(emug)

Inconel 600 Heat treated at

602 oC under tensile stress

1 2 3

How can we detect magnetic phase

(PVC)selectively from the flaws in SGT

-3000 -2000 -1000 0 1000 2000 3000

-006

H (Oe)

7 8 9

10 11 12

-3000 -2000 -1000 0 1000 2000 3000

-006

-004

H(Oe)

4 5 6

7 8 9

The hysteresis loop of the tensile tested specimen at room temperature (a) and tensile tested at high temperature (b)

The magnetic phase can be created under the high temperature andpressure conditions which is correspond to the stress corrosion crackingin the SG tube in the NPP(Bruemmer SM Charlot LA amp Henager CH (1988) Corrosion 782)

Principle of ECT

If we can separate magnetic phase selectively from the

flaws using magnetic sensor the reliability of EC in SGT

inspection will be greatly enhanced

Structure of the permeability

sensor

Dimension and photograph of U-shape

sensing yoke

Design of Magnetic Sensor for PVC

sensor sensing yoke

Photograph of the completed sensor front side (above) and rear side (bottom)

R11R12

R10

R8

R6

R9

R13

R7

R14

C18

1 n

C17

C20

C21

D2

DIODE

SIN COS

-

+

U-2A

4

13

2

-

+

U-2B

75

6

8

-

+

U-3A

13

2

8

+5VC19

104

+5V

Schematic diagram of the sensor system

Electronic Circuit of Magnetic Sensor

R20

R

R21

R

-

+

U5AD797

3

26

74

U6

D1

S12

GND3

+VCC4VCC5

IN6

-VCC7

S28

C41

R13

R26

R18

R25

R2210 Ω

R16

R14

R17

10 k

R15

R27

R32

R28

R33

R29

R34

5 k

R30

C29

C37

104

C32473

C39473C40

104

C33

104

C21

104C23

104

C25

104

C26

104

C30

104

C31

104

C35

104

C36

104

C27

104

C28

104

C34

104

C38

104

D3

DIODE

L1

1

2

L2

1

2

L3

1

2

4

-

+

U-4A

4

13

2

-

+

U-4B

75

6

8

-

+

U-5A

4

13

2

-

+

U-5B

75

6

8

-

+

U-6A

4

13

2

-

+

U-6B

75

6

8

C22

104

-5V

+5V

+5V

+5V

+5V

+5V

+5V

U7

D1

S12

GND3

+VCC4

VCC5

IN6

-VCC7

S28

+5V

-5V

-5V

-5V

-5V

-5V

-5V

-5V

-5V

R19

R24

R

R23

R

C24

OUT(X)

OUT(Y)

R1

20 kR210 k

R3

20 kR410 k

C1

104

C8

104

REF43

OUT(X)

OUT(Y)

REF43

U2

+Vcc1

CH02

CH13

CH24

CH35

COMM6

SHDN7

Vref8

+Vcc9

GND10

GND11

DOUT12BUSY13DIN14CS15

DIN16

-

+

U-1A

13

2

8

-

+

U-1B

4

75

6

C410 uF

C5104

DOUT

C210uF

C6104

C3104

DCLK

C7104

DIN

C10

01uF

CS

BUSY

C14 10uF

J1

CON6

123456

D1

DIODE

R5

47K

C9

10uF

C1310uF

Y1

OSC

OUT3

GND2

VCC4

U3

RSTVPP1

GND10

VCC20

XTAL15

XTAL24

P10AIN012P11AIN113P1214P1315P1416P1517P1618P1719

P30RXD2

P31TXD3

P32INT06

P33INT17

P34T08

P35T19

P3711

U4

C1+1

C1-3

C2+4

C2-5

VCC16

GND15

V+2

V-6

R1OUT12

R2OUT9

T1IN11

T2IN10

R1IN13

R2IN8

T1OUT14

T2OUT7

C12 10uF

C16

01uF

C15 10uF

C11

01uF

-5V

+5V

+5V

+5V

+5V

+5V

+5V

+5V

RST

OSC

OSC

RST

DCLKCSDINBUSYDOUT

U1

IN2

GND

4

OUT6

TEMP3

TRIM5

-5V

+5V

Electronic circuit diagram of the magnetic sensor

Photograph of the completed measuring system data acquisition

software in PC and probe scanning system

Experimental Setup for Magnetic Sensor

Reference material Scanning System Software LabVIEW

Reference Material (1) Normal defects and PVCs

Longitudinal and transverse defects

Def W L D Remarks

1 02 500 0213 (20 ) Inner defects

2 02 500 0427 (40 )

3 02 500 0213 (20 )Outer defectsPVC(1018)4 02 500 0427 (40 )

5 02 500 0639 (60 )

6 02 500 0852 (80 )

7 02 500 0639 (60 ) Inner defects

8 02 500 0852 (80 )

- 1 and 2 are inner defects

- 345 and 6 are outer defects with PVC

- 7 and 8 are inner defects

PVC

PVC

Defect Defect

For longitudinal defects and PVC For circumferential defects and PVC

ECT is very difficult to detect circumferential defects

We can distinguish PVCs and defects and longitudinal and circumferential defects

Flux-gate Magnetometer

One core sensor Two core sensor

3-축 flux-gate Magnetometer의 계략도

Sensorpia Co

pro

cess

or(

AV

R)

Sensor 1

RS422

Interface

Mic

ro-p

roce

ssor(

AV

R)

Sensor 2

Sensor 3

Interface

조립된 마그네토미터의 사진

Sensorpia Co

Analog PCB

Digital PCB

Sensorpia Co선형도(linearity)

10

20

30

40

50

60

y-axis

Magnetometer Output (microT)

-60 -50 -40 -30 -20 -10 0 10 20 30 40 50 60

-60

-50

-40

-30

-20

-10

0

10

Y-axis y=099946 x+0015STD 106E-4

Magnetometer Output (

Applied Magnetic Field (microT)

마그네토미터의 noise 특성 Sensorpia Co

1

10

100

y-axis

Magnetometer noise (nT)

0 1 2 3 4 5 6

1E-4

1E-3

001

01

Magnetometer noise (nT)

Frequency (Hz)

Magnetometer for KoDSAT

-150 -100 -50 0 50 100 150

-15

-10

-5

0

5

10

15

Magnetic Moment (Am

2)

Current (mA)

After Thermal Cycle Test

Measured

Resistance 193 ohm

Photograph of Magnetic torquer

Photograph of KoDSAT

Photograph of

3-axis Fluxgate

Magnetometer

Photograph of Magnetic torquer

Application of magnetometer

Moon magnetic fieldmeasurement

Telescope with direction indication

Joule Effect (Magnetostriction)

ϕ2cosel

l=

∆

0=∆

+∆

+∆

b

b

a

a

l

l

Actuator using Terfenol-D

00

05

10

B (T)

800

1000

1200

1400

1600

Magnetostriction (ppm)

-100 -50 0 50 100

-10

-05

00

B (T)

H (kAm)

2 MPa

4 MPa

6 MPa

8 MPa

10 MPa

12 MPa

-100 -50 0 50 100

-200

0

200

400

600

Magnetostriction (ppm)

H (kAm)

2 MPa

4 MPa

6 MPa

8 MPa

10 MPa

12 MPa

600

700

800

900

1000

-4 -3 -2 -1 0 1 2 3 4

0

10

20

30

40

50

60

Displacement (m

icro meter)

I (A)

FIELD

9 kAm

12 kAm

16 kAm

20 kAm

24 kAm

38 kAm

-50 -40 -30 -20 -10 0 10 20 30 40 50

-100

0

100

200

300

400

500

L (PPM)

H (kAm)

9 kAm

12 kAm

16 kAm

20 kAm

24 kAm

38 kAm

Magnetostrictive displacement sensor

Hysteresis loops under

tensile stress σ

(a) Crystalline 68 NiFe

λs = +25 10-6

(b) crystalline pure Ni λs

= -35 10-6

Villari Effect ( Inverse of Joule Effect)

= -35 10-6

(c) amorphous Co-based

alloy

λs = -35 10-6

ϕσλ 2sin2

3sdotsdot= smeE

γ

Permeability depending on the stress

σλmicromicro

1

3

2

Y

J

so

s

r =

γ

Calculated magnetization curves under stress

Variation of magnetization curve by an applied

tensile force (Co-based amorphous alloy)

Alloy Requirement

Materials for magnetoelastic sensors

Why amorphous magnetic materials are important

Stress-strain curves of several materials

Coercivity and hardness of several materials

Principles of magnetoelastic sensors

Non-contact torque sensor

Principle of cross torductor torque

sensor and flux pattern of sensor

poles on the surface of a shaft

a) without and b)with torsional load

Equivalent magnetic circuit of

cross type torque sensor

Helices of principal tensile and compressive stress on the surface of

a shaft subjected to torsion [32] Correlated changes of permeability

are detected by four-branch yoke system with sensing coils 123

and 4 and a common excitation pole

Examples of torque sensors

Four-branch type torque sensor

heads Pole structures realized

by commercial multi-pole

ferrites 14 and 18 min in

diameter (diameter of sensor

h e a d 1 7 a n d 2 4 m m

respectively) respectively)

Principle of Ring Torductor torque transducer

(a b) Physical structure (c) evolution of the

shaft surface under the transducer poles A and BRing torductor for measuring

torque on ship propeller shafts

(shaft diameter ca 500 mm)

(Courtesy ASEA Brown

Boveri AG)

Principal designs of coaxial torque sensors

Schematic diagram of data processing

electronics of a torque sensor

Extensometer (a) Construction of strain sensing element using

amorphous ribbon wound core (b) configuration of lumped

windings

∆E effect of an amorphous FeNi-based

alloy (Fe40 Ni38 Mo4 B18) Hs saturation

field

Magnetically tunable delay line

Torque Sensors using Amorphous wire

Sixtus tonk효과(large Barkhausen효과)

Hysteresis loops of a Wiegand wire for different reset fields

Curie 온도 및Hopkinson효과

Relation between normalised

saturation polarisation and

normalised Curie temperature

Permeability of a Mn-Zn ferrite as

a function of temperature and field

strength

Conclusions

1) Magnetic sensor 는 자동차 공장자동화 항공우주 및 군사용으로많이 사용되고 있다

2) 새로운 소재개발은 자기센서의 성능개발에 직접적인 영향을 준다2) 새로운 소재개발은 자기센서의 성능개발에 직접적인 영향을 준다

3) 센서의 개발을 위해서는 다양한 전공지식이 요구된다

(물리학 재료공학 기계공학 전자공학)

4) 센서분야가 고부가가치를 창출하는 부품사업이다

5) 핵심부품을 생산하는 중소기업의 item으로도 적절하다

Magnetization of a high permeability core

dt

dnu ci

i Φ

sdotminus= ) ( cosmaxc ci tωsdotΦ=Φ

ci0rc0 maxAHnnU sdotsdotsdotsdot=Φsdotsdot= micromicroωω

HNHHHH )1( minusminus=+= micro

HN

H sdotminus+

=)1(1

1

r

i micro

irdmi HNHHHH )1( minusminus=+= micro

HfAnU sdotsdotsdotsdotsdotsdot= 0cc0 2 micromicroπ

)1(1 r

rc minus+=

micromicro

microN

minus++

minusminus=

infin1)1ln(

11

1 2

22ell mmm

m

mN

10326) (1ln 152

10156) (1ln 262

ell

cyl

++++

=infin

infin

N

N

Induction coil on a cylindrical high permeability core

Demagnetization factorDemagnetization factorN of prolate ellipsoidsand cylindrical rods(descending curves) andcore permeability μc

(ascending curves) ofcylindrical rods versusthe length-to-diameterratio m of the rod withmaterial permeability μr

as parameter

Core permeability μc of cylindrical rods versus thematerial permeability μr with length-to-diameter ratiom of the rod as parameter after

Minimum noise equivalent magnetic field spectral density of an induction coil sensor with high permeability core versus sensor weight Ws (at length-to-diameter ratios m = 50 and 100 permeability μr = 10000 of the core material and f = 1 Hz)

Induction coil sensors with electronic amplifier

II

rKLC

1=ω

II

II

RR

RK

+=

rr

2 i 1

)(

ωω

ωω

ω

D

KF

+

minus

=

+=

II

II

II

2

C

L

R

R

C

L

KD

Frequency responses of the search coil

Frequency responses of thesensitivity SA and the output voltage UA

of an induction coil sensor with a voltageamplifier at a constant magnetic fieldamplitude

Resonance step-up of thesensitivity SA at differentvalues of the damping D

Sensor with transformer coupled negative feedback to the coil

)(i)()(F

0 ωωωω FR

UMUAU A

A sdot

minus=

)( i1

)(

F

0

ωω

ω

FR

MA

FAUU A

sdot+

sdot=

Induction coil connected to a voltage amplifier with

transformer coupled negative feedback to the coil

FR

21

1K0

i1

1

i1

i )(

ωωωωωω

ωω

+sdot

+sdot=

M

RUU A

IIF2 CRL

MAf

sdotsdotsdotsdot

=∆π

Frequency response of the output voltage UA of an induction coil sensor with negative feedback transformer coupled to the coil

Applications of search coil magnetometer

Developed search coil magnetometer using amorphous ribbon

Experimental setup for the effective permeability measurement

Relative permeability depending on the numbers of ribbon(a)

and the air gap between ribbons

Relative permeability depending on the number of ribbons for the different air gap between ribbons

Relative permeability depending on the total number of ribbons for the different air gap between ribbons

10 pT

100 pT

1 pT

Noise spectrum of the developed search coil magnetometer

BJne

E xH

1minus=

neRH

1minus=

22 nP micromicro minus

Hall 효과

Bt

IRU H

HL =

2

22

)( he

eh

Hpne

nPR

micromicromicromicro

+

minus=

Rectangular Hall plate (cc1cc2 current constant sc1sc2

sensor constant I bias current U voltage drop UH Hall

voltage

Physics carrier concentration and kind of carrier measurement

Engineering magnetic field measurement

Current Measurement

Arrangement for noninvasive

current measurement using an iron

core The current to be measured

produces a proportional magnetic

field which can be measured in the

air gap

Characteristic curve produced by

the current

Arrangement for indirect noninvasive

current measurement using the

compensation principle An iron core as

represented in Figure 3-29 is held field

free by injection a current into a

compensating coil wound on the core

which offsets the field generated by the

current being measured The Hall effect

sensor in the air gap serves as a null

indicator

Circuit diagram for AC-power

measurement using a Hall effect

sensor

DC Power Measurement

Circuit diagram for DC-

power measurement using a

Hall effect sensor

Noncontact Position Sensing

Galvanomagnetic components for sensing the position of permanent magnets

and magnetically conductive materials

Current Sensor Based on Hall Sensor

and Magnetic Core for Hybrid Vehicle

KH Yeon1 SD Kim1 and D Son2 1Auto industry co14F Hanshin IT tower Guro Gu Seoul Korea2Hannam UniversityOjung dong 133 Daejeon Rep of Korea

i

Hall sensor

B

I

SB

ring core

B

I10

g

N

Bl S

micro

)( gtgtrmicro

gab core

Current Sensor Based on Hall

Sensor and Magnetic Core

Hall

Effect

Device

CurrentVoltage

applying for

Hall effect device

operation

Output

signals

Magnetic field

Occurred by

current measurement

Signal

process

circuits

Developed Current Sensor

Magnetic core

Hall sensor

PCB

25

30

35

40

45

50

Output voltage V

Current sensor(Open loop type)

Temp 25C

400A model

+400 ~ -400A

SD 000128

Linearity 003

Linearity of the sensor

Characteristics of the Current Sensors

1000A 10 V power supply

-500 -400 -300 -200 -100 0 100 200 300 400 500

00

05

10

15

20

Output voltage V

current A

Temperature 25Linearity 003

Measuring range -400A ~ +400A

1000A Electronic Load

-3

0

3

6

9

12

15

18

dB

Current sensor

DV2 PCB 24pF

40Aturns

Frequency bandwidth

Gain bandwidth 3 MHz

Current 10 A

Temperature 25

Frequency bandwidth 100 kHz

Sensor output voltage vs frequency

at applied current of 40 Aturns

1 10 100

-18

-15

-12

-9

-6

Frequency kHz 측정온도 25

주파수특성 30kHz 이상(3dB 기준)

측정전류 40Aturns(4A 10턴)

측정주파수 100Hz ~ 100kHz

Temperature 25Current 40Aturns

Frequency range 100 Hz ~ 100 kHz

What is Magnetoresistance

Magnetoresistance effect(AMR)

θθθ 2cos2

12sin12cos(

22 minusminus+∆asymp∆ xxxmx hhhRR

32 minusasymp∆ ρρ New effect GMR CMR and GMI

10 ge∆ ρρ

Two bridge configuration for

rotational angle measurement

measurement angle more than 180o

자동차 Engine Management System

Inductive and Eddy Current

Sensors Excited by Permanent Magnets

tNtU dd)( φsdotminus=

construction of an inductive

sensor (courtesy VDO Adolf sensor (courtesy VDO Adolf

Schindling AG)

1) constant socket

2) terminal package

3) permanent magnet

4) cap

5) soft magnetic core

6) coil

7) plate

8) blade connector

γγ

Sensor with yoke Change in the magnetic flux with

varying air gap Continuous lines

minimum air gap dashed lines

maximum air gap

C-shaped sensor

Sensor with radially

magnetized

permanent magnet

Signal Conditioning

Output voltage U of a DC-excited sensor with permanent

magnets when a single iron object passes by

Schematic electrical diagram of an inductive sensor

Linear Variable Differential Transformer

AC-Excited Sensors for Linear Movement

Principle of construction of an LVDT

Electrical circuit of an LVDT

tIMtNU dd dd sdotminus=sdotminus= φ

tIMtIMUUU dd dd 1212 sdotminussdot=minus=

tIMMU dd)( 12 sdotminus=

)(12 xMMMM =minus=

tIxMU dd)( sdot= tI

UxM

dd)( =

Signal Conditioning

power supply

carrier gen

autoampcontrol

LVDTcarrieramp

demod-ulator

phase

shifter

power supply

carrier gen

passivedemod-ulator

LVDTDCamp

Block diagram of a carrier amplifier system

Block diagram of a DC amplifier system

Variable Inductive Sensors

Principle of construction

of the VLP sensor

Principle of a bridge

circuit

lANL r 20 sdotsdotsdot= micromicro

21 BA UUU minus=

21)i(ii( 211 minus+sdot= LLLUU BA ωωω

)21))()((( minus∆minus+∆+∆+sdot= LLLLLLUU BA

)212)(( minus∆+sdot= LLLUU )212)(( minus∆+sdot= LLLUU BA

LLUU BA 21 ∆sdotsdot=

llLL ∆sdot=∆ d d

llLLUU BA ∆sdotsdot= d d)2(1

Applications and Properties

Principle of a construction of a force transducer

(courtesy Hottinger Baldwin Messtechnik)

Vibrationacceleration sensor

Signal Conditioning

Schematic electrical diagram of a force transducer connected with an

amplifier (courtesy Hottinger Baldwin Messtechnik GmbH)

Variable Gap Sensors

)( FeFe2

0 LLllANL micromicromicro +sdotsdot=

FeFe2

0max lANL sdotsdotsdot= micromicro

Construction of a variable gap sensor

Characteristic of a variable gap sensor

Construction of a differential

cross-anchor sensor

Output voltage U versus core

position x plusmn a limits of the

linear rage

Applications of differential cross-anchor sensors

AC-excited Sensors for Rotary Movements

Principle of construction of a synchro

α cos10 sdotsdot= UKU y

)120-( cos10 degsdotsdot= αUKU z

)240-( cos10 degsdotsdot= αUKU x

)120-( sin3100 degsdotsdotsdot=minus= αKUUUU yxyx

)240-( sin3100 degsdotsdotsdot=minus= αKUUUU zyzy

α sin3100 sdotsdotsdot=minus= KUUUU xzxz

Application to the Torque Sensor

Principle of construction of a torque-type synchro

Torque versus angular

difference

)( sin~ rt αα minussdotKM

)( cos~ rt1r αα minussdotUU

Principle of construction of a control-type sensor

Output voltage versus

angular difference

Principle of construction of a differential sychro

Eddy Current Sensors

tBE dd curl minus=JH = curl

0 div =BH(H)B sdot= micro

E(E)J sdot= σ

A B curl= A B curl=

tdd- A E =

)dd( tAJ minus= σ

tdd curl curl AA σmicro minus=

AA) σωmicro iminus= curl )(curl(1

AA) σωmicro i=∆)((1

Eddy Current Tachometer

Construction of a speedometer (courtesy VDO Adolf Schinding AG) 1) spindle 2) bearing

3) holding spring 4) iron yoke 5) eddy current cup 6) shaft of the magnet 7) support of

the magnet 8) temperature compensation 9) permanent magnet 10) torsion spring

Proximity Sensors

Schematic diagram of a proximity sensor

Output current of a proximity switch versus distance

Inductive Flowmeters

)( Btimessdot= υqF

EqF sdot=BE times=υ

)(ds Btimes== υEU )(ds Btimes== υEU

)( Bd timessdot= υU

Bsdotsdotsdot= υdKU

Development of magnetic phase detection

sensor for steam generator tube

Dirac Son1 Kwan-Sang Ryu2 Duck-Gun Park3

1Hannam University Daejeon Rep of Korea2Korea Research Institute of Standards and Science Daejeon Rep of Korea3KoreaAtomic Energy Research Institute Daejeon Rep of Korea

Introduction

The layout of pressurized water reactor (PWR) components

Primary side Secondary side (non-radioactive side)(radioactive side)

The Structure of SG(Steam Generator)(degradation mechanism)

Secondary SidePrimary Side

SCC

A B

A-B

Steam outlet

Anti-vibration

SCC

Fretting

Wall thinning

IGA

U-bend

In commercial power plants SG- height up to 21 m - weight up to 800 tons - 2~4 sets of SG were installed - SG can contain from 3000 to

16000 tubes each about 20 mmin diameter

Primary coolant outlet Primary coolant inlet

Anti-vibrationbars

Tubesupportplate

Tubesheet

IGA

SCC

Pitting

SCC

Inside Tubesheet

Top of Tubesheet

by SSHwang of KAERI

Denting

Sludge pile

in diameter

The SGT is made of nickel basedInconel alloy which is composed of 75 Ni 165Cr and 815Fe

-Degradation mechanism corrosion pitting denting inter granular attack

-Inspection Eddy current Testing(ECT)

Permeability Variation Clusters (PVC)

(Ferro-magnetic phase)

-005

000

005

010

015

m (emug)

1-1

-002

000

002

004

006

008

m (emug)

1-2

-1000 -500 0 500 1000

-015

-010

-005

H ( Am )

-1000 -500 0 500 1000

-006

-004

-002

H ( Am )

The hystresis loop in the fragment of PVC parts of Kori-1 retired SG tube

-004

-002

000

002

004

006

M (emug)

Inconel 600 tested at RT

under tensile stress

1 2 3

4 5 6

7 8 9-004

-002

000

002

004

006

M(emug)

Inconel 600 Heat treated at

602 oC under tensile stress

1 2 3

How can we detect magnetic phase

(PVC)selectively from the flaws in SGT

-3000 -2000 -1000 0 1000 2000 3000

-006

H (Oe)

7 8 9

10 11 12

-3000 -2000 -1000 0 1000 2000 3000

-006

-004

H(Oe)

4 5 6

7 8 9

The hysteresis loop of the tensile tested specimen at room temperature (a) and tensile tested at high temperature (b)

The magnetic phase can be created under the high temperature andpressure conditions which is correspond to the stress corrosion crackingin the SG tube in the NPP(Bruemmer SM Charlot LA amp Henager CH (1988) Corrosion 782)

Principle of ECT

If we can separate magnetic phase selectively from the

flaws using magnetic sensor the reliability of EC in SGT

inspection will be greatly enhanced

Structure of the permeability

sensor

Dimension and photograph of U-shape

sensing yoke

Design of Magnetic Sensor for PVC

sensor sensing yoke

Photograph of the completed sensor front side (above) and rear side (bottom)

R11R12

R10

R8

R6

R9

R13

R7

R14

C18

1 n

C17

C20

C21

D2

DIODE

SIN COS

-

+

U-2A

4

13

2

-

+

U-2B

75

6

8

-

+

U-3A

13

2

8

+5VC19

104

+5V

Schematic diagram of the sensor system

Electronic Circuit of Magnetic Sensor

R20

R

R21

R

-

+

U5AD797

3

26

74

U6

D1

S12

GND3

+VCC4VCC5

IN6

-VCC7

S28

C41

R13

R26

R18

R25

R2210 Ω

R16

R14

R17

10 k

R15

R27

R32

R28

R33

R29

R34

5 k

R30

C29

C37

104

C32473

C39473C40

104

C33

104

C21

104C23

104

C25

104

C26

104

C30

104

C31

104

C35

104

C36

104

C27

104

C28

104

C34

104

C38

104

D3

DIODE

L1

1

2

L2

1

2

L3

1

2

4

-

+

U-4A

4

13

2

-

+

U-4B

75

6

8

-

+

U-5A

4

13

2

-

+

U-5B

75

6

8

-

+

U-6A

4

13

2

-

+

U-6B

75

6

8

C22

104

-5V

+5V

+5V

+5V

+5V

+5V

+5V

U7

D1

S12

GND3

+VCC4

VCC5

IN6

-VCC7

S28

+5V

-5V

-5V

-5V

-5V

-5V

-5V

-5V

-5V

R19

R24

R

R23

R

C24

OUT(X)

OUT(Y)

R1

20 kR210 k

R3

20 kR410 k

C1

104

C8

104

REF43

OUT(X)

OUT(Y)

REF43

U2

+Vcc1

CH02

CH13

CH24

CH35

COMM6

SHDN7

Vref8

+Vcc9

GND10

GND11

DOUT12BUSY13DIN14CS15

DIN16

-

+

U-1A

13

2

8

-

+

U-1B

4

75

6

C410 uF

C5104

DOUT

C210uF

C6104

C3104

DCLK

C7104

DIN

C10

01uF

CS

BUSY

C14 10uF

J1

CON6

123456

D1

DIODE

R5

47K

C9

10uF

C1310uF

Y1

OSC

OUT3

GND2

VCC4

U3

RSTVPP1

GND10

VCC20

XTAL15

XTAL24

P10AIN012P11AIN113P1214P1315P1416P1517P1618P1719

P30RXD2

P31TXD3

P32INT06

P33INT17

P34T08

P35T19

P3711

U4

C1+1

C1-3

C2+4

C2-5

VCC16

GND15

V+2

V-6

R1OUT12

R2OUT9

T1IN11

T2IN10

R1IN13

R2IN8

T1OUT14

T2OUT7

C12 10uF

C16

01uF

C15 10uF

C11

01uF

-5V

+5V

+5V

+5V

+5V

+5V

+5V

+5V

RST

OSC

OSC

RST

DCLKCSDINBUSYDOUT

U1

IN2

GND

4

OUT6

TEMP3

TRIM5

-5V

+5V

Electronic circuit diagram of the magnetic sensor

Photograph of the completed measuring system data acquisition

software in PC and probe scanning system

Experimental Setup for Magnetic Sensor

Reference material Scanning System Software LabVIEW

Reference Material (1) Normal defects and PVCs

Longitudinal and transverse defects

Def W L D Remarks

1 02 500 0213 (20 ) Inner defects

2 02 500 0427 (40 )

3 02 500 0213 (20 )Outer defectsPVC(1018)4 02 500 0427 (40 )

5 02 500 0639 (60 )

6 02 500 0852 (80 )

7 02 500 0639 (60 ) Inner defects

8 02 500 0852 (80 )

- 1 and 2 are inner defects

- 345 and 6 are outer defects with PVC

- 7 and 8 are inner defects

PVC

PVC

Defect Defect

For longitudinal defects and PVC For circumferential defects and PVC

ECT is very difficult to detect circumferential defects

We can distinguish PVCs and defects and longitudinal and circumferential defects

Flux-gate Magnetometer

One core sensor Two core sensor

3-축 flux-gate Magnetometer의 계략도

Sensorpia Co

pro

cess

or(

AV

R)

Sensor 1

RS422

Interface

Mic

ro-p

roce

ssor(

AV

R)

Sensor 2

Sensor 3

Interface

조립된 마그네토미터의 사진

Sensorpia Co

Analog PCB

Digital PCB

Sensorpia Co선형도(linearity)

10

20

30

40

50

60

y-axis

Magnetometer Output (microT)

-60 -50 -40 -30 -20 -10 0 10 20 30 40 50 60

-60

-50

-40

-30

-20

-10

0

10

Y-axis y=099946 x+0015STD 106E-4

Magnetometer Output (

Applied Magnetic Field (microT)

마그네토미터의 noise 특성 Sensorpia Co

1

10

100

y-axis

Magnetometer noise (nT)

0 1 2 3 4 5 6

1E-4

1E-3

001

01

Magnetometer noise (nT)

Frequency (Hz)

Magnetometer for KoDSAT

-150 -100 -50 0 50 100 150

-15

-10

-5

0

5

10

15

Magnetic Moment (Am

2)

Current (mA)

After Thermal Cycle Test

Measured

Resistance 193 ohm

Photograph of Magnetic torquer

Photograph of KoDSAT

Photograph of

3-axis Fluxgate

Magnetometer

Photograph of Magnetic torquer

Application of magnetometer

Moon magnetic fieldmeasurement

Telescope with direction indication

Joule Effect (Magnetostriction)

ϕ2cosel

l=

∆

0=∆

+∆

+∆

b

b

a

a

l

l

Actuator using Terfenol-D

00

05

10

B (T)

800

1000

1200

1400

1600

Magnetostriction (ppm)

-100 -50 0 50 100

-10

-05

00

B (T)

H (kAm)

2 MPa

4 MPa

6 MPa

8 MPa

10 MPa

12 MPa

-100 -50 0 50 100

-200

0

200

400

600

Magnetostriction (ppm)

H (kAm)

2 MPa

4 MPa

6 MPa

8 MPa

10 MPa

12 MPa

600

700

800

900

1000

-4 -3 -2 -1 0 1 2 3 4

0

10

20

30

40

50

60

Displacement (m

icro meter)

I (A)

FIELD

9 kAm

12 kAm

16 kAm

20 kAm

24 kAm

38 kAm

-50 -40 -30 -20 -10 0 10 20 30 40 50

-100

0

100

200

300

400

500

L (PPM)

H (kAm)

9 kAm

12 kAm

16 kAm

20 kAm

24 kAm

38 kAm

Magnetostrictive displacement sensor

Hysteresis loops under

tensile stress σ

(a) Crystalline 68 NiFe

λs = +25 10-6

(b) crystalline pure Ni λs

= -35 10-6

Villari Effect ( Inverse of Joule Effect)

= -35 10-6

(c) amorphous Co-based

alloy

λs = -35 10-6

ϕσλ 2sin2

3sdotsdot= smeE

γ

Permeability depending on the stress

σλmicromicro

1

3

2

Y

J

so

s

r =

γ

Calculated magnetization curves under stress

Variation of magnetization curve by an applied

tensile force (Co-based amorphous alloy)

Alloy Requirement

Materials for magnetoelastic sensors

Why amorphous magnetic materials are important

Stress-strain curves of several materials

Coercivity and hardness of several materials

Principles of magnetoelastic sensors

Non-contact torque sensor

Principle of cross torductor torque

sensor and flux pattern of sensor

poles on the surface of a shaft

a) without and b)with torsional load

Equivalent magnetic circuit of

cross type torque sensor

Helices of principal tensile and compressive stress on the surface of

a shaft subjected to torsion [32] Correlated changes of permeability

are detected by four-branch yoke system with sensing coils 123

and 4 and a common excitation pole

Examples of torque sensors

Four-branch type torque sensor

heads Pole structures realized

by commercial multi-pole

ferrites 14 and 18 min in

diameter (diameter of sensor

h e a d 1 7 a n d 2 4 m m

respectively) respectively)

Principle of Ring Torductor torque transducer

(a b) Physical structure (c) evolution of the

shaft surface under the transducer poles A and BRing torductor for measuring

torque on ship propeller shafts

(shaft diameter ca 500 mm)

(Courtesy ASEA Brown

Boveri AG)

Principal designs of coaxial torque sensors

Schematic diagram of data processing

electronics of a torque sensor

Extensometer (a) Construction of strain sensing element using

amorphous ribbon wound core (b) configuration of lumped

windings

∆E effect of an amorphous FeNi-based

alloy (Fe40 Ni38 Mo4 B18) Hs saturation

field

Magnetically tunable delay line

Torque Sensors using Amorphous wire

Sixtus tonk효과(large Barkhausen효과)

Hysteresis loops of a Wiegand wire for different reset fields

Curie 온도 및Hopkinson효과

Relation between normalised

saturation polarisation and

normalised Curie temperature

Permeability of a Mn-Zn ferrite as

a function of temperature and field

strength

Conclusions

1) Magnetic sensor 는 자동차 공장자동화 항공우주 및 군사용으로많이 사용되고 있다

2) 새로운 소재개발은 자기센서의 성능개발에 직접적인 영향을 준다2) 새로운 소재개발은 자기센서의 성능개발에 직접적인 영향을 준다

3) 센서의 개발을 위해서는 다양한 전공지식이 요구된다

(물리학 재료공학 기계공학 전자공학)

4) 센서분야가 고부가가치를 창출하는 부품사업이다

5) 핵심부품을 생산하는 중소기업의 item으로도 적절하다

minus++

minusminus=

infin1)1ln(

11

1 2

22ell mmm

m

mN

10326) (1ln 152

10156) (1ln 262

ell

cyl

++++

=infin

infin

N

N

Induction coil on a cylindrical high permeability core

Demagnetization factorDemagnetization factorN of prolate ellipsoidsand cylindrical rods(descending curves) andcore permeability μc

(ascending curves) ofcylindrical rods versusthe length-to-diameterratio m of the rod withmaterial permeability μr

as parameter

Core permeability μc of cylindrical rods versus thematerial permeability μr with length-to-diameter ratiom of the rod as parameter after

Minimum noise equivalent magnetic field spectral density of an induction coil sensor with high permeability core versus sensor weight Ws (at length-to-diameter ratios m = 50 and 100 permeability μr = 10000 of the core material and f = 1 Hz)

Induction coil sensors with electronic amplifier

II

rKLC

1=ω

II

II

RR

RK

+=

rr

2 i 1

)(

ωω

ωω

ω

D

KF

+

minus

=

+=

II

II

II

2

C

L

R

R

C

L

KD

Frequency responses of the search coil

Frequency responses of thesensitivity SA and the output voltage UA

of an induction coil sensor with a voltageamplifier at a constant magnetic fieldamplitude

Resonance step-up of thesensitivity SA at differentvalues of the damping D

Sensor with transformer coupled negative feedback to the coil

)(i)()(F

0 ωωωω FR

UMUAU A

A sdot

minus=

)( i1

)(

F

0

ωω

ω

FR

MA

FAUU A

sdot+

sdot=

Induction coil connected to a voltage amplifier with

transformer coupled negative feedback to the coil

FR

21

1K0

i1

1

i1

i )(

ωωωωωω

ωω

+sdot

+sdot=

M

RUU A

IIF2 CRL

MAf

sdotsdotsdotsdot

=∆π

Frequency response of the output voltage UA of an induction coil sensor with negative feedback transformer coupled to the coil

Applications of search coil magnetometer

Developed search coil magnetometer using amorphous ribbon

Experimental setup for the effective permeability measurement

Relative permeability depending on the numbers of ribbon(a)

and the air gap between ribbons

Relative permeability depending on the number of ribbons for the different air gap between ribbons

Relative permeability depending on the total number of ribbons for the different air gap between ribbons

10 pT

100 pT

1 pT

Noise spectrum of the developed search coil magnetometer

BJne

E xH

1minus=

neRH

1minus=

22 nP micromicro minus

Hall 효과

Bt

IRU H

HL =

2

22

)( he

eh

Hpne

nPR

micromicromicromicro

+

minus=

Rectangular Hall plate (cc1cc2 current constant sc1sc2

sensor constant I bias current U voltage drop UH Hall

voltage

Physics carrier concentration and kind of carrier measurement

Engineering magnetic field measurement

Current Measurement

Arrangement for noninvasive

current measurement using an iron

core The current to be measured

produces a proportional magnetic

field which can be measured in the

air gap

Characteristic curve produced by

the current

Arrangement for indirect noninvasive

current measurement using the

compensation principle An iron core as

represented in Figure 3-29 is held field

free by injection a current into a

compensating coil wound on the core

which offsets the field generated by the

current being measured The Hall effect

sensor in the air gap serves as a null

indicator

Circuit diagram for AC-power

measurement using a Hall effect

sensor

DC Power Measurement

Circuit diagram for DC-

power measurement using a

Hall effect sensor

Noncontact Position Sensing

Galvanomagnetic components for sensing the position of permanent magnets

and magnetically conductive materials

Current Sensor Based on Hall Sensor

and Magnetic Core for Hybrid Vehicle

KH Yeon1 SD Kim1 and D Son2 1Auto industry co14F Hanshin IT tower Guro Gu Seoul Korea2Hannam UniversityOjung dong 133 Daejeon Rep of Korea

i

Hall sensor

B

I

SB

ring core

B

I10

g

N

Bl S

micro

)( gtgtrmicro

gab core

Current Sensor Based on Hall

Sensor and Magnetic Core

Hall

Effect

Device

CurrentVoltage

applying for

Hall effect device

operation

Output

signals

Magnetic field

Occurred by

current measurement

Signal

process

circuits

Developed Current Sensor

Magnetic core

Hall sensor

PCB

25

30

35

40

45

50

Output voltage V

Current sensor(Open loop type)

Temp 25C

400A model

+400 ~ -400A

SD 000128

Linearity 003

Linearity of the sensor

Characteristics of the Current Sensors

1000A 10 V power supply

-500 -400 -300 -200 -100 0 100 200 300 400 500

00

05

10

15

20

Output voltage V

current A

Temperature 25Linearity 003

Measuring range -400A ~ +400A

1000A Electronic Load

-3

0

3

6

9

12

15

18

dB

Current sensor

DV2 PCB 24pF

40Aturns

Frequency bandwidth

Gain bandwidth 3 MHz

Current 10 A

Temperature 25

Frequency bandwidth 100 kHz

Sensor output voltage vs frequency

at applied current of 40 Aturns

1 10 100

-18

-15

-12

-9

-6

Frequency kHz 측정온도 25

주파수특성 30kHz 이상(3dB 기준)

측정전류 40Aturns(4A 10턴)

측정주파수 100Hz ~ 100kHz

Temperature 25Current 40Aturns

Frequency range 100 Hz ~ 100 kHz

What is Magnetoresistance

Magnetoresistance effect(AMR)

θθθ 2cos2

12sin12cos(

22 minusminus+∆asymp∆ xxxmx hhhRR

32 minusasymp∆ ρρ New effect GMR CMR and GMI

10 ge∆ ρρ

Two bridge configuration for

rotational angle measurement

measurement angle more than 180o

자동차 Engine Management System

Inductive and Eddy Current

Sensors Excited by Permanent Magnets

tNtU dd)( φsdotminus=

construction of an inductive

sensor (courtesy VDO Adolf sensor (courtesy VDO Adolf

Schindling AG)

1) constant socket

2) terminal package

3) permanent magnet

4) cap

5) soft magnetic core

6) coil

7) plate

8) blade connector

γγ

Sensor with yoke Change in the magnetic flux with

varying air gap Continuous lines

minimum air gap dashed lines

maximum air gap

C-shaped sensor

Sensor with radially

magnetized

permanent magnet

Signal Conditioning

Output voltage U of a DC-excited sensor with permanent

magnets when a single iron object passes by

Schematic electrical diagram of an inductive sensor

Linear Variable Differential Transformer

AC-Excited Sensors for Linear Movement

Principle of construction of an LVDT

Electrical circuit of an LVDT

tIMtNU dd dd sdotminus=sdotminus= φ

tIMtIMUUU dd dd 1212 sdotminussdot=minus=

tIMMU dd)( 12 sdotminus=

)(12 xMMMM =minus=

tIxMU dd)( sdot= tI

UxM

dd)( =

Signal Conditioning

power supply

carrier gen

autoampcontrol

LVDTcarrieramp

demod-ulator

phase

shifter

power supply

carrier gen

passivedemod-ulator

LVDTDCamp

Block diagram of a carrier amplifier system

Block diagram of a DC amplifier system

Variable Inductive Sensors

Principle of construction

of the VLP sensor

Principle of a bridge

circuit

lANL r 20 sdotsdotsdot= micromicro

21 BA UUU minus=

21)i(ii( 211 minus+sdot= LLLUU BA ωωω

)21))()((( minus∆minus+∆+∆+sdot= LLLLLLUU BA

)212)(( minus∆+sdot= LLLUU )212)(( minus∆+sdot= LLLUU BA

LLUU BA 21 ∆sdotsdot=

llLL ∆sdot=∆ d d

llLLUU BA ∆sdotsdot= d d)2(1

Applications and Properties

Principle of a construction of a force transducer

(courtesy Hottinger Baldwin Messtechnik)

Vibrationacceleration sensor

Signal Conditioning

Schematic electrical diagram of a force transducer connected with an

amplifier (courtesy Hottinger Baldwin Messtechnik GmbH)

Variable Gap Sensors

)( FeFe2

0 LLllANL micromicromicro +sdotsdot=

FeFe2

0max lANL sdotsdotsdot= micromicro

Construction of a variable gap sensor

Characteristic of a variable gap sensor

Construction of a differential

cross-anchor sensor

Output voltage U versus core

position x plusmn a limits of the

linear rage

Applications of differential cross-anchor sensors

AC-excited Sensors for Rotary Movements

Principle of construction of a synchro

α cos10 sdotsdot= UKU y

)120-( cos10 degsdotsdot= αUKU z

)240-( cos10 degsdotsdot= αUKU x

)120-( sin3100 degsdotsdotsdot=minus= αKUUUU yxyx

)240-( sin3100 degsdotsdotsdot=minus= αKUUUU zyzy

α sin3100 sdotsdotsdot=minus= KUUUU xzxz

Application to the Torque Sensor

Principle of construction of a torque-type synchro

Torque versus angular

difference

)( sin~ rt αα minussdotKM

)( cos~ rt1r αα minussdotUU

Principle of construction of a control-type sensor

Output voltage versus

angular difference

Principle of construction of a differential sychro

Eddy Current Sensors

tBE dd curl minus=JH = curl

0 div =BH(H)B sdot= micro

E(E)J sdot= σ

A B curl= A B curl=

tdd- A E =

)dd( tAJ minus= σ

tdd curl curl AA σmicro minus=

AA) σωmicro iminus= curl )(curl(1

AA) σωmicro i=∆)((1

Eddy Current Tachometer

Construction of a speedometer (courtesy VDO Adolf Schinding AG) 1) spindle 2) bearing

3) holding spring 4) iron yoke 5) eddy current cup 6) shaft of the magnet 7) support of

the magnet 8) temperature compensation 9) permanent magnet 10) torsion spring

Proximity Sensors

Schematic diagram of a proximity sensor

Output current of a proximity switch versus distance

Inductive Flowmeters

)( Btimessdot= υqF

EqF sdot=BE times=υ

)(ds Btimes== υEU )(ds Btimes== υEU

)( Bd timessdot= υU

Bsdotsdotsdot= υdKU

Development of magnetic phase detection

sensor for steam generator tube

Dirac Son1 Kwan-Sang Ryu2 Duck-Gun Park3

1Hannam University Daejeon Rep of Korea2Korea Research Institute of Standards and Science Daejeon Rep of Korea3KoreaAtomic Energy Research Institute Daejeon Rep of Korea

Introduction

The layout of pressurized water reactor (PWR) components

Primary side Secondary side (non-radioactive side)(radioactive side)

The Structure of SG(Steam Generator)(degradation mechanism)

Secondary SidePrimary Side

SCC

A B

A-B

Steam outlet

Anti-vibration

SCC

Fretting

Wall thinning

IGA

U-bend

In commercial power plants SG- height up to 21 m - weight up to 800 tons - 2~4 sets of SG were installed - SG can contain from 3000 to

16000 tubes each about 20 mmin diameter

Primary coolant outlet Primary coolant inlet

Anti-vibrationbars

Tubesupportplate

Tubesheet

IGA

SCC

Pitting

SCC

Inside Tubesheet

Top of Tubesheet

by SSHwang of KAERI

Denting

Sludge pile

in diameter

The SGT is made of nickel basedInconel alloy which is composed of 75 Ni 165Cr and 815Fe

-Degradation mechanism corrosion pitting denting inter granular attack

-Inspection Eddy current Testing(ECT)

Permeability Variation Clusters (PVC)

(Ferro-magnetic phase)

-005

000

005

010

015

m (emug)

1-1

-002

000

002

004

006

008

m (emug)

1-2

-1000 -500 0 500 1000

-015

-010

-005

H ( Am )

-1000 -500 0 500 1000

-006

-004

-002

H ( Am )

The hystresis loop in the fragment of PVC parts of Kori-1 retired SG tube

-004

-002

000

002

004

006

M (emug)

Inconel 600 tested at RT

under tensile stress

1 2 3

4 5 6

7 8 9-004

-002

000

002

004

006

M(emug)

Inconel 600 Heat treated at

602 oC under tensile stress

1 2 3

How can we detect magnetic phase

(PVC)selectively from the flaws in SGT

-3000 -2000 -1000 0 1000 2000 3000

-006

H (Oe)

7 8 9

10 11 12

-3000 -2000 -1000 0 1000 2000 3000

-006

-004

H(Oe)

4 5 6

7 8 9

The hysteresis loop of the tensile tested specimen at room temperature (a) and tensile tested at high temperature (b)

The magnetic phase can be created under the high temperature andpressure conditions which is correspond to the stress corrosion crackingin the SG tube in the NPP(Bruemmer SM Charlot LA amp Henager CH (1988) Corrosion 782)

Principle of ECT

If we can separate magnetic phase selectively from the

flaws using magnetic sensor the reliability of EC in SGT

inspection will be greatly enhanced

Structure of the permeability

sensor

Dimension and photograph of U-shape

sensing yoke

Design of Magnetic Sensor for PVC

sensor sensing yoke

Photograph of the completed sensor front side (above) and rear side (bottom)

R11R12

R10

R8

R6

R9

R13

R7

R14

C18

1 n

C17

C20

C21

D2

DIODE

SIN COS

-

+

U-2A

4

13

2

-

+

U-2B

75

6

8

-

+

U-3A

13

2

8

+5VC19

104

+5V

Schematic diagram of the sensor system

Electronic Circuit of Magnetic Sensor

R20

R

R21

R

-

+

U5AD797

3

26

74

U6

D1

S12

GND3

+VCC4VCC5

IN6

-VCC7

S28

C41

R13

R26

R18

R25

R2210 Ω

R16

R14

R17

10 k

R15

R27

R32

R28

R33

R29

R34

5 k

R30

C29

C37

104

C32473

C39473C40

104

C33

104

C21

104C23

104

C25

104

C26

104

C30

104

C31

104

C35

104

C36

104

C27

104

C28

104

C34

104

C38

104

D3

DIODE

L1

1

2

L2

1

2

L3

1

2

4

-

+

U-4A

4

13

2

-

+

U-4B

75

6

8

-

+

U-5A

4

13

2

-

+

U-5B

75

6

8

-

+

U-6A

4

13

2

-

+

U-6B

75

6

8

C22

104

-5V

+5V

+5V

+5V

+5V

+5V

+5V

U7

D1

S12

GND3

+VCC4

VCC5

IN6

-VCC7

S28

+5V

-5V

-5V

-5V

-5V

-5V

-5V

-5V

-5V

R19

R24

R

R23

R

C24

OUT(X)

OUT(Y)

R1

20 kR210 k

R3

20 kR410 k

C1

104

C8

104

REF43

OUT(X)

OUT(Y)

REF43

U2

+Vcc1

CH02

CH13

CH24

CH35

COMM6

SHDN7

Vref8

+Vcc9

GND10

GND11

DOUT12BUSY13DIN14CS15

DIN16

-

+

U-1A

13

2

8

-

+

U-1B

4

75

6

C410 uF

C5104

DOUT

C210uF

C6104

C3104

DCLK

C7104

DIN

C10

01uF

CS

BUSY

C14 10uF

J1

CON6

123456

D1

DIODE

R5

47K

C9

10uF

C1310uF

Y1

OSC

OUT3

GND2

VCC4

U3

RSTVPP1

GND10

VCC20

XTAL15

XTAL24

P10AIN012P11AIN113P1214P1315P1416P1517P1618P1719

P30RXD2

P31TXD3

P32INT06

P33INT17

P34T08

P35T19

P3711

U4

C1+1

C1-3

C2+4

C2-5

VCC16

GND15

V+2

V-6

R1OUT12

R2OUT9

T1IN11

T2IN10

R1IN13

R2IN8

T1OUT14

T2OUT7

C12 10uF

C16

01uF

C15 10uF

C11

01uF

-5V

+5V

+5V

+5V

+5V

+5V

+5V

+5V

RST

OSC

OSC

RST

DCLKCSDINBUSYDOUT

U1

IN2

GND

4

OUT6

TEMP3

TRIM5

-5V

+5V

Electronic circuit diagram of the magnetic sensor

Photograph of the completed measuring system data acquisition

software in PC and probe scanning system

Experimental Setup for Magnetic Sensor

Reference material Scanning System Software LabVIEW

Reference Material (1) Normal defects and PVCs

Longitudinal and transverse defects

Def W L D Remarks

1 02 500 0213 (20 ) Inner defects

2 02 500 0427 (40 )

3 02 500 0213 (20 )Outer defectsPVC(1018)4 02 500 0427 (40 )

5 02 500 0639 (60 )

6 02 500 0852 (80 )

7 02 500 0639 (60 ) Inner defects

8 02 500 0852 (80 )

- 1 and 2 are inner defects

- 345 and 6 are outer defects with PVC

- 7 and 8 are inner defects

PVC

PVC

Defect Defect

For longitudinal defects and PVC For circumferential defects and PVC

ECT is very difficult to detect circumferential defects

We can distinguish PVCs and defects and longitudinal and circumferential defects

Flux-gate Magnetometer

One core sensor Two core sensor

3-축 flux-gate Magnetometer의 계략도

Sensorpia Co

pro

cess

or(

AV

R)

Sensor 1

RS422

Interface

Mic

ro-p

roce

ssor(

AV

R)

Sensor 2

Sensor 3

Interface

조립된 마그네토미터의 사진

Sensorpia Co

Analog PCB

Digital PCB

Sensorpia Co선형도(linearity)

10

20

30

40

50

60

y-axis

Magnetometer Output (microT)

-60 -50 -40 -30 -20 -10 0 10 20 30 40 50 60

-60

-50

-40

-30

-20

-10

0

10

Y-axis y=099946 x+0015STD 106E-4

Magnetometer Output (

Applied Magnetic Field (microT)

마그네토미터의 noise 특성 Sensorpia Co

1

10

100

y-axis

Magnetometer noise (nT)

0 1 2 3 4 5 6

1E-4

1E-3

001

01

Magnetometer noise (nT)

Frequency (Hz)

Magnetometer for KoDSAT

-150 -100 -50 0 50 100 150

-15

-10

-5

0

5

10

15

Magnetic Moment (Am

2)

Current (mA)

After Thermal Cycle Test

Measured

Resistance 193 ohm

Photograph of Magnetic torquer

Photograph of KoDSAT

Photograph of

3-axis Fluxgate

Magnetometer

Photograph of Magnetic torquer

Application of magnetometer

Moon magnetic fieldmeasurement

Telescope with direction indication

Joule Effect (Magnetostriction)

ϕ2cosel

l=

∆

0=∆

+∆

+∆

b

b

a

a

l

l

Actuator using Terfenol-D

00

05

10

B (T)

800

1000

1200

1400

1600

Magnetostriction (ppm)

-100 -50 0 50 100

-10

-05

00

B (T)

H (kAm)

2 MPa

4 MPa

6 MPa

8 MPa

10 MPa

12 MPa

-100 -50 0 50 100

-200

0

200

400

600

Magnetostriction (ppm)

H (kAm)

2 MPa

4 MPa

6 MPa

8 MPa

10 MPa

12 MPa

600

700

800

900

1000

-4 -3 -2 -1 0 1 2 3 4

0

10

20

30

40

50

60

Displacement (m

icro meter)

I (A)

FIELD

9 kAm

12 kAm

16 kAm

20 kAm

24 kAm

38 kAm

-50 -40 -30 -20 -10 0 10 20 30 40 50

-100

0

100

200

300

400

500

L (PPM)

H (kAm)

9 kAm

12 kAm

16 kAm

20 kAm

24 kAm

38 kAm

Magnetostrictive displacement sensor

Hysteresis loops under

tensile stress σ

(a) Crystalline 68 NiFe

λs = +25 10-6

(b) crystalline pure Ni λs

= -35 10-6

Villari Effect ( Inverse of Joule Effect)

= -35 10-6

(c) amorphous Co-based

alloy

λs = -35 10-6

ϕσλ 2sin2

3sdotsdot= smeE

γ

Permeability depending on the stress

σλmicromicro

1

3

2

Y

J

so

s

r =

γ

Calculated magnetization curves under stress

Variation of magnetization curve by an applied

tensile force (Co-based amorphous alloy)

Alloy Requirement

Materials for magnetoelastic sensors

Why amorphous magnetic materials are important

Stress-strain curves of several materials

Coercivity and hardness of several materials

Principles of magnetoelastic sensors

Non-contact torque sensor

Principle of cross torductor torque

sensor and flux pattern of sensor

poles on the surface of a shaft

a) without and b)with torsional load

Equivalent magnetic circuit of

cross type torque sensor

Helices of principal tensile and compressive stress on the surface of

a shaft subjected to torsion [32] Correlated changes of permeability

are detected by four-branch yoke system with sensing coils 123

and 4 and a common excitation pole

Examples of torque sensors

Four-branch type torque sensor

heads Pole structures realized

by commercial multi-pole

ferrites 14 and 18 min in

diameter (diameter of sensor

h e a d 1 7 a n d 2 4 m m

respectively) respectively)

Principle of Ring Torductor torque transducer

(a b) Physical structure (c) evolution of the

shaft surface under the transducer poles A and BRing torductor for measuring

torque on ship propeller shafts

(shaft diameter ca 500 mm)

(Courtesy ASEA Brown

Boveri AG)

Principal designs of coaxial torque sensors

Schematic diagram of data processing

electronics of a torque sensor

Extensometer (a) Construction of strain sensing element using

amorphous ribbon wound core (b) configuration of lumped

windings

∆E effect of an amorphous FeNi-based

alloy (Fe40 Ni38 Mo4 B18) Hs saturation

field

Magnetically tunable delay line

Torque Sensors using Amorphous wire

Sixtus tonk효과(large Barkhausen효과)

Hysteresis loops of a Wiegand wire for different reset fields

Curie 온도 및Hopkinson효과

Relation between normalised

saturation polarisation and

normalised Curie temperature

Permeability of a Mn-Zn ferrite as

a function of temperature and field

strength

Conclusions

1) Magnetic sensor 는 자동차 공장자동화 항공우주 및 군사용으로많이 사용되고 있다

2) 새로운 소재개발은 자기센서의 성능개발에 직접적인 영향을 준다2) 새로운 소재개발은 자기센서의 성능개발에 직접적인 영향을 준다

3) 센서의 개발을 위해서는 다양한 전공지식이 요구된다

(물리학 재료공학 기계공학 전자공학)

4) 센서분야가 고부가가치를 창출하는 부품사업이다

5) 핵심부품을 생산하는 중소기업의 item으로도 적절하다

Demagnetization factorDemagnetization factorN of prolate ellipsoidsand cylindrical rods(descending curves) andcore permeability μc

(ascending curves) ofcylindrical rods versusthe length-to-diameterratio m of the rod withmaterial permeability μr

as parameter

Core permeability μc of cylindrical rods versus thematerial permeability μr with length-to-diameter ratiom of the rod as parameter after

Minimum noise equivalent magnetic field spectral density of an induction coil sensor with high permeability core versus sensor weight Ws (at length-to-diameter ratios m = 50 and 100 permeability μr = 10000 of the core material and f = 1 Hz)

Induction coil sensors with electronic amplifier

II

rKLC

1=ω

II

II

RR

RK

+=

rr

2 i 1

)(

ωω

ωω

ω

D

KF

+

minus

=

+=

II

II

II

2

C

L

R

R

C

L

KD

Frequency responses of the search coil

Frequency responses of thesensitivity SA and the output voltage UA

of an induction coil sensor with a voltageamplifier at a constant magnetic fieldamplitude

Resonance step-up of thesensitivity SA at differentvalues of the damping D

Sensor with transformer coupled negative feedback to the coil

)(i)()(F

0 ωωωω FR

UMUAU A

A sdot

minus=

)( i1

)(

F

0

ωω

ω

FR

MA

FAUU A

sdot+

sdot=

Induction coil connected to a voltage amplifier with

transformer coupled negative feedback to the coil

FR

21

1K0

i1

1

i1

i )(

ωωωωωω

ωω

+sdot

+sdot=

M

RUU A

IIF2 CRL

MAf

sdotsdotsdotsdot

=∆π

Frequency response of the output voltage UA of an induction coil sensor with negative feedback transformer coupled to the coil

Applications of search coil magnetometer

Developed search coil magnetometer using amorphous ribbon

Experimental setup for the effective permeability measurement

Relative permeability depending on the numbers of ribbon(a)

and the air gap between ribbons

Relative permeability depending on the number of ribbons for the different air gap between ribbons

Relative permeability depending on the total number of ribbons for the different air gap between ribbons

10 pT

100 pT

1 pT

Noise spectrum of the developed search coil magnetometer

BJne

E xH

1minus=

neRH

1minus=

22 nP micromicro minus

Hall 효과

Bt

IRU H

HL =

2

22

)( he

eh

Hpne

nPR

micromicromicromicro

+

minus=

Rectangular Hall plate (cc1cc2 current constant sc1sc2

sensor constant I bias current U voltage drop UH Hall

voltage

Physics carrier concentration and kind of carrier measurement

Engineering magnetic field measurement

Current Measurement

Arrangement for noninvasive

current measurement using an iron

core The current to be measured

produces a proportional magnetic

field which can be measured in the

air gap

Characteristic curve produced by

the current

Arrangement for indirect noninvasive

current measurement using the

compensation principle An iron core as

represented in Figure 3-29 is held field

free by injection a current into a

compensating coil wound on the core

which offsets the field generated by the

current being measured The Hall effect

sensor in the air gap serves as a null

indicator

Circuit diagram for AC-power

measurement using a Hall effect

sensor

DC Power Measurement

Circuit diagram for DC-

power measurement using a

Hall effect sensor

Noncontact Position Sensing

Galvanomagnetic components for sensing the position of permanent magnets

and magnetically conductive materials

Current Sensor Based on Hall Sensor

and Magnetic Core for Hybrid Vehicle

KH Yeon1 SD Kim1 and D Son2 1Auto industry co14F Hanshin IT tower Guro Gu Seoul Korea2Hannam UniversityOjung dong 133 Daejeon Rep of Korea

i

Hall sensor

B

I

SB

ring core

B

I10

g

N

Bl S

micro

)( gtgtrmicro

gab core

Current Sensor Based on Hall

Sensor and Magnetic Core

Hall

Effect

Device

CurrentVoltage

applying for

Hall effect device

operation

Output

signals

Magnetic field

Occurred by

current measurement

Signal

process

circuits

Developed Current Sensor

Magnetic core

Hall sensor

PCB

25

30

35

40

45

50

Output voltage V

Current sensor(Open loop type)

Temp 25C

400A model

+400 ~ -400A

SD 000128

Linearity 003

Linearity of the sensor

Characteristics of the Current Sensors

1000A 10 V power supply

-500 -400 -300 -200 -100 0 100 200 300 400 500

00

05

10

15

20

Output voltage V

current A

Temperature 25Linearity 003

Measuring range -400A ~ +400A

1000A Electronic Load

-3

0

3

6

9

12

15

18

dB

Current sensor

DV2 PCB 24pF

40Aturns

Frequency bandwidth

Gain bandwidth 3 MHz

Current 10 A

Temperature 25

Frequency bandwidth 100 kHz

Sensor output voltage vs frequency

at applied current of 40 Aturns

1 10 100

-18

-15

-12

-9

-6

Frequency kHz 측정온도 25

주파수특성 30kHz 이상(3dB 기준)

측정전류 40Aturns(4A 10턴)

측정주파수 100Hz ~ 100kHz

Temperature 25Current 40Aturns

Frequency range 100 Hz ~ 100 kHz

What is Magnetoresistance

Magnetoresistance effect(AMR)

θθθ 2cos2

12sin12cos(

22 minusminus+∆asymp∆ xxxmx hhhRR

32 minusasymp∆ ρρ New effect GMR CMR and GMI

10 ge∆ ρρ

Two bridge configuration for

rotational angle measurement

measurement angle more than 180o

자동차 Engine Management System

Inductive and Eddy Current

Sensors Excited by Permanent Magnets

tNtU dd)( φsdotminus=

construction of an inductive

sensor (courtesy VDO Adolf sensor (courtesy VDO Adolf

Schindling AG)

1) constant socket

2) terminal package

3) permanent magnet

4) cap

5) soft magnetic core

6) coil

7) plate

8) blade connector

γγ

Sensor with yoke Change in the magnetic flux with

varying air gap Continuous lines

minimum air gap dashed lines

maximum air gap

C-shaped sensor

Sensor with radially

magnetized

permanent magnet

Signal Conditioning

Output voltage U of a DC-excited sensor with permanent

magnets when a single iron object passes by

Schematic electrical diagram of an inductive sensor

Linear Variable Differential Transformer

AC-Excited Sensors for Linear Movement

Principle of construction of an LVDT

Electrical circuit of an LVDT

tIMtNU dd dd sdotminus=sdotminus= φ

tIMtIMUUU dd dd 1212 sdotminussdot=minus=

tIMMU dd)( 12 sdotminus=

)(12 xMMMM =minus=

tIxMU dd)( sdot= tI

UxM

dd)( =

Signal Conditioning

power supply

carrier gen

autoampcontrol

LVDTcarrieramp

demod-ulator

phase

shifter

power supply

carrier gen

passivedemod-ulator

LVDTDCamp

Block diagram of a carrier amplifier system

Block diagram of a DC amplifier system

Variable Inductive Sensors

Principle of construction

of the VLP sensor

Principle of a bridge

circuit

lANL r 20 sdotsdotsdot= micromicro

21 BA UUU minus=

21)i(ii( 211 minus+sdot= LLLUU BA ωωω

)21))()((( minus∆minus+∆+∆+sdot= LLLLLLUU BA

)212)(( minus∆+sdot= LLLUU )212)(( minus∆+sdot= LLLUU BA

LLUU BA 21 ∆sdotsdot=

llLL ∆sdot=∆ d d

llLLUU BA ∆sdotsdot= d d)2(1

Applications and Properties

Principle of a construction of a force transducer

(courtesy Hottinger Baldwin Messtechnik)

Vibrationacceleration sensor

Signal Conditioning

Schematic electrical diagram of a force transducer connected with an

amplifier (courtesy Hottinger Baldwin Messtechnik GmbH)

Variable Gap Sensors

)( FeFe2

0 LLllANL micromicromicro +sdotsdot=

FeFe2

0max lANL sdotsdotsdot= micromicro

Construction of a variable gap sensor

Characteristic of a variable gap sensor

Construction of a differential

cross-anchor sensor

Output voltage U versus core

position x plusmn a limits of the

linear rage

Applications of differential cross-anchor sensors

AC-excited Sensors for Rotary Movements

Principle of construction of a synchro

α cos10 sdotsdot= UKU y

)120-( cos10 degsdotsdot= αUKU z

)240-( cos10 degsdotsdot= αUKU x

)120-( sin3100 degsdotsdotsdot=minus= αKUUUU yxyx

)240-( sin3100 degsdotsdotsdot=minus= αKUUUU zyzy

α sin3100 sdotsdotsdot=minus= KUUUU xzxz

Application to the Torque Sensor

Principle of construction of a torque-type synchro

Torque versus angular

difference

)( sin~ rt αα minussdotKM

)( cos~ rt1r αα minussdotUU

Principle of construction of a control-type sensor

Output voltage versus

angular difference

Principle of construction of a differential sychro

Eddy Current Sensors

tBE dd curl minus=JH = curl

0 div =BH(H)B sdot= micro

E(E)J sdot= σ

A B curl= A B curl=

tdd- A E =

)dd( tAJ minus= σ

tdd curl curl AA σmicro minus=

AA) σωmicro iminus= curl )(curl(1

AA) σωmicro i=∆)((1

Eddy Current Tachometer

Construction of a speedometer (courtesy VDO Adolf Schinding AG) 1) spindle 2) bearing

3) holding spring 4) iron yoke 5) eddy current cup 6) shaft of the magnet 7) support of

the magnet 8) temperature compensation 9) permanent magnet 10) torsion spring

Proximity Sensors

Schematic diagram of a proximity sensor

Output current of a proximity switch versus distance

Inductive Flowmeters

)( Btimessdot= υqF

EqF sdot=BE times=υ

)(ds Btimes== υEU )(ds Btimes== υEU

)( Bd timessdot= υU

Bsdotsdotsdot= υdKU

Development of magnetic phase detection

sensor for steam generator tube

Dirac Son1 Kwan-Sang Ryu2 Duck-Gun Park3

1Hannam University Daejeon Rep of Korea2Korea Research Institute of Standards and Science Daejeon Rep of Korea3KoreaAtomic Energy Research Institute Daejeon Rep of Korea

Introduction

The layout of pressurized water reactor (PWR) components

Primary side Secondary side (non-radioactive side)(radioactive side)

The Structure of SG(Steam Generator)(degradation mechanism)

Secondary SidePrimary Side

SCC

A B

A-B

Steam outlet

Anti-vibration

SCC

Fretting

Wall thinning

IGA

U-bend

In commercial power plants SG- height up to 21 m - weight up to 800 tons - 2~4 sets of SG were installed - SG can contain from 3000 to

16000 tubes each about 20 mmin diameter

Primary coolant outlet Primary coolant inlet

Anti-vibrationbars

Tubesupportplate

Tubesheet

IGA

SCC

Pitting

SCC

Inside Tubesheet

Top of Tubesheet

by SSHwang of KAERI

Denting

Sludge pile

in diameter

The SGT is made of nickel basedInconel alloy which is composed of 75 Ni 165Cr and 815Fe

-Degradation mechanism corrosion pitting denting inter granular attack

-Inspection Eddy current Testing(ECT)

Permeability Variation Clusters (PVC)

(Ferro-magnetic phase)

-005

000

005

010

015

m (emug)

1-1

-002

000

002

004

006

008

m (emug)

1-2

-1000 -500 0 500 1000

-015

-010

-005

H ( Am )

-1000 -500 0 500 1000

-006

-004

-002

H ( Am )

The hystresis loop in the fragment of PVC parts of Kori-1 retired SG tube

-004

-002

000

002

004

006

M (emug)

Inconel 600 tested at RT

under tensile stress

1 2 3

4 5 6

7 8 9-004

-002

000

002

004

006

M(emug)

Inconel 600 Heat treated at

602 oC under tensile stress

1 2 3

How can we detect magnetic phase

(PVC)selectively from the flaws in SGT

-3000 -2000 -1000 0 1000 2000 3000

-006

H (Oe)

7 8 9

10 11 12

-3000 -2000 -1000 0 1000 2000 3000

-006

-004

H(Oe)

4 5 6

7 8 9

The hysteresis loop of the tensile tested specimen at room temperature (a) and tensile tested at high temperature (b)

The magnetic phase can be created under the high temperature andpressure conditions which is correspond to the stress corrosion crackingin the SG tube in the NPP(Bruemmer SM Charlot LA amp Henager CH (1988) Corrosion 782)

Principle of ECT

If we can separate magnetic phase selectively from the

flaws using magnetic sensor the reliability of EC in SGT

inspection will be greatly enhanced

Structure of the permeability

sensor

Dimension and photograph of U-shape

sensing yoke

Design of Magnetic Sensor for PVC

sensor sensing yoke

Photograph of the completed sensor front side (above) and rear side (bottom)

R11R12

R10

R8

R6

R9

R13

R7

R14

C18

1 n

C17

C20

C21

D2

DIODE

SIN COS

-

+

U-2A

4

13

2

-

+

U-2B

75

6

8

-

+

U-3A

13

2

8

+5VC19

104

+5V

Schematic diagram of the sensor system

Electronic Circuit of Magnetic Sensor

R20

R

R21

R

-

+

U5AD797

3

26

74

U6

D1

S12

GND3

+VCC4VCC5

IN6

-VCC7

S28

C41

R13

R26

R18

R25

R2210 Ω

R16

R14

R17

10 k

R15

R27

R32

R28

R33

R29

R34

5 k

R30

C29

C37

104

C32473

C39473C40

104

C33

104

C21

104C23

104

C25

104

C26

104

C30

104

C31

104

C35

104

C36

104

C27

104

C28

104

C34

104

C38

104

D3

DIODE

L1

1

2

L2

1

2

L3

1

2

4

-

+

U-4A

4

13

2

-

+

U-4B

75

6

8

-

+

U-5A

4

13

2

-

+

U-5B

75

6

8

-

+

U-6A

4

13

2

-

+

U-6B

75

6

8

C22

104

-5V

+5V

+5V

+5V

+5V

+5V

+5V

U7

D1

S12

GND3

+VCC4

VCC5

IN6

-VCC7

S28

+5V

-5V

-5V

-5V

-5V

-5V

-5V

-5V

-5V

R19

R24

R

R23

R

C24

OUT(X)

OUT(Y)

R1

20 kR210 k

R3

20 kR410 k

C1

104

C8

104

REF43

OUT(X)

OUT(Y)

REF43

U2

+Vcc1

CH02

CH13

CH24

CH35

COMM6

SHDN7

Vref8

+Vcc9

GND10

GND11

DOUT12BUSY13DIN14CS15

DIN16

-

+

U-1A

13

2

8

-

+

U-1B

4

75

6

C410 uF

C5104

DOUT

C210uF

C6104

C3104

DCLK

C7104

DIN

C10

01uF

CS

BUSY

C14 10uF

J1

CON6

123456

D1

DIODE

R5

47K

C9

10uF

C1310uF

Y1

OSC

OUT3

GND2

VCC4

U3

RSTVPP1

GND10

VCC20

XTAL15

XTAL24

P10AIN012P11AIN113P1214P1315P1416P1517P1618P1719

P30RXD2

P31TXD3

P32INT06

P33INT17

P34T08

P35T19

P3711

U4

C1+1

C1-3

C2+4

C2-5

VCC16

GND15

V+2

V-6

R1OUT12

R2OUT9

T1IN11

T2IN10

R1IN13

R2IN8

T1OUT14

T2OUT7

C12 10uF

C16

01uF

C15 10uF

C11

01uF

-5V

+5V

+5V

+5V

+5V

+5V

+5V

+5V

RST

OSC

OSC

RST

DCLKCSDINBUSYDOUT

U1

IN2

GND

4

OUT6

TEMP3

TRIM5

-5V

+5V

Electronic circuit diagram of the magnetic sensor

Photograph of the completed measuring system data acquisition

software in PC and probe scanning system

Experimental Setup for Magnetic Sensor

Reference material Scanning System Software LabVIEW

Reference Material (1) Normal defects and PVCs

Longitudinal and transverse defects

Def W L D Remarks

1 02 500 0213 (20 ) Inner defects

2 02 500 0427 (40 )

3 02 500 0213 (20 )Outer defectsPVC(1018)4 02 500 0427 (40 )

5 02 500 0639 (60 )

6 02 500 0852 (80 )

7 02 500 0639 (60 ) Inner defects

8 02 500 0852 (80 )

- 1 and 2 are inner defects

- 345 and 6 are outer defects with PVC

- 7 and 8 are inner defects

PVC

PVC

Defect Defect

For longitudinal defects and PVC For circumferential defects and PVC

ECT is very difficult to detect circumferential defects

We can distinguish PVCs and defects and longitudinal and circumferential defects

Flux-gate Magnetometer

One core sensor Two core sensor

3-축 flux-gate Magnetometer의 계략도

Sensorpia Co

pro

cess

or(

AV

R)

Sensor 1

RS422

Interface

Mic

ro-p

roce

ssor(

AV

R)

Sensor 2

Sensor 3

Interface

조립된 마그네토미터의 사진

Sensorpia Co

Analog PCB

Digital PCB

Sensorpia Co선형도(linearity)

10

20

30

40

50

60

y-axis

Magnetometer Output (microT)

-60 -50 -40 -30 -20 -10 0 10 20 30 40 50 60

-60

-50

-40

-30

-20

-10

0

10

Y-axis y=099946 x+0015STD 106E-4

Magnetometer Output (

Applied Magnetic Field (microT)

마그네토미터의 noise 특성 Sensorpia Co

1

10

100

y-axis

Magnetometer noise (nT)

0 1 2 3 4 5 6

1E-4

1E-3

001

01

Magnetometer noise (nT)

Frequency (Hz)

Magnetometer for KoDSAT

-150 -100 -50 0 50 100 150

-15

-10

-5

0

5

10

15

Magnetic Moment (Am

2)

Current (mA)

After Thermal Cycle Test

Measured

Resistance 193 ohm

Photograph of Magnetic torquer

Photograph of KoDSAT

Photograph of

3-axis Fluxgate

Magnetometer

Photograph of Magnetic torquer

Application of magnetometer

Moon magnetic fieldmeasurement

Telescope with direction indication

Joule Effect (Magnetostriction)

ϕ2cosel

l=

∆

0=∆

+∆

+∆

b

b

a

a

l

l

Actuator using Terfenol-D

00

05

10

B (T)

800

1000

1200

1400

1600

Magnetostriction (ppm)

-100 -50 0 50 100

-10

-05

00

B (T)

H (kAm)

2 MPa

4 MPa

6 MPa

8 MPa

10 MPa

12 MPa

-100 -50 0 50 100

-200

0

200

400

600

Magnetostriction (ppm)

H (kAm)

2 MPa

4 MPa

6 MPa

8 MPa

10 MPa

12 MPa

600

700

800

900

1000

-4 -3 -2 -1 0 1 2 3 4

0

10

20

30

40

50

60

Displacement (m

icro meter)

I (A)

FIELD

9 kAm

12 kAm

16 kAm

20 kAm

24 kAm

38 kAm

-50 -40 -30 -20 -10 0 10 20 30 40 50

-100

0

100

200

300

400

500

L (PPM)

H (kAm)

9 kAm

12 kAm

16 kAm

20 kAm

24 kAm

38 kAm

Magnetostrictive displacement sensor

Hysteresis loops under

tensile stress σ

(a) Crystalline 68 NiFe

λs = +25 10-6

(b) crystalline pure Ni λs

= -35 10-6

Villari Effect ( Inverse of Joule Effect)

= -35 10-6

(c) amorphous Co-based

alloy

λs = -35 10-6

ϕσλ 2sin2

3sdotsdot= smeE

γ

Permeability depending on the stress

σλmicromicro

1

3

2

Y

J

so

s

r =

γ

Calculated magnetization curves under stress

Variation of magnetization curve by an applied

tensile force (Co-based amorphous alloy)

Alloy Requirement

Materials for magnetoelastic sensors

Why amorphous magnetic materials are important

Stress-strain curves of several materials

Coercivity and hardness of several materials

Principles of magnetoelastic sensors

Non-contact torque sensor

Principle of cross torductor torque

sensor and flux pattern of sensor

poles on the surface of a shaft

a) without and b)with torsional load

Equivalent magnetic circuit of

cross type torque sensor

Helices of principal tensile and compressive stress on the surface of

a shaft subjected to torsion [32] Correlated changes of permeability

are detected by four-branch yoke system with sensing coils 123

and 4 and a common excitation pole

Examples of torque sensors

Four-branch type torque sensor

heads Pole structures realized

by commercial multi-pole

ferrites 14 and 18 min in

diameter (diameter of sensor

h e a d 1 7 a n d 2 4 m m

respectively) respectively)

Principle of Ring Torductor torque transducer

(a b) Physical structure (c) evolution of the

shaft surface under the transducer poles A and BRing torductor for measuring

torque on ship propeller shafts

(shaft diameter ca 500 mm)

(Courtesy ASEA Brown

Boveri AG)

Principal designs of coaxial torque sensors

Schematic diagram of data processing

electronics of a torque sensor

Extensometer (a) Construction of strain sensing element using

amorphous ribbon wound core (b) configuration of lumped

windings

∆E effect of an amorphous FeNi-based

alloy (Fe40 Ni38 Mo4 B18) Hs saturation

field

Magnetically tunable delay line

Torque Sensors using Amorphous wire

Sixtus tonk효과(large Barkhausen효과)

Hysteresis loops of a Wiegand wire for different reset fields

Curie 온도 및Hopkinson효과

Relation between normalised

saturation polarisation and

normalised Curie temperature

Permeability of a Mn-Zn ferrite as

a function of temperature and field

strength

Conclusions

1) Magnetic sensor 는 자동차 공장자동화 항공우주 및 군사용으로많이 사용되고 있다

2) 새로운 소재개발은 자기센서의 성능개발에 직접적인 영향을 준다2) 새로운 소재개발은 자기센서의 성능개발에 직접적인 영향을 준다

3) 센서의 개발을 위해서는 다양한 전공지식이 요구된다

(물리학 재료공학 기계공학 전자공학)

4) 센서분야가 고부가가치를 창출하는 부품사업이다

5) 핵심부품을 생산하는 중소기업의 item으로도 적절하다

Core permeability μc of cylindrical rods versus thematerial permeability μr with length-to-diameter ratiom of the rod as parameter after

Minimum noise equivalent magnetic field spectral density of an induction coil sensor with high permeability core versus sensor weight Ws (at length-to-diameter ratios m = 50 and 100 permeability μr = 10000 of the core material and f = 1 Hz)

Induction coil sensors with electronic amplifier

II

rKLC

1=ω

II

II

RR

RK

+=

rr

2 i 1

)(

ωω

ωω

ω

D

KF

+

minus

=

+=

II

II

II

2

C

L

R

R

C

L

KD

Frequency responses of the search coil

Frequency responses of thesensitivity SA and the output voltage UA

of an induction coil sensor with a voltageamplifier at a constant magnetic fieldamplitude

Resonance step-up of thesensitivity SA at differentvalues of the damping D

Sensor with transformer coupled negative feedback to the coil

)(i)()(F

0 ωωωω FR

UMUAU A

A sdot

minus=

)( i1

)(

F

0

ωω

ω

FR

MA

FAUU A

sdot+

sdot=

Induction coil connected to a voltage amplifier with

transformer coupled negative feedback to the coil

FR

21

1K0

i1

1

i1

i )(

ωωωωωω

ωω

+sdot

+sdot=

M

RUU A

IIF2 CRL

MAf

sdotsdotsdotsdot

=∆π

Frequency response of the output voltage UA of an induction coil sensor with negative feedback transformer coupled to the coil

Applications of search coil magnetometer

Developed search coil magnetometer using amorphous ribbon

Experimental setup for the effective permeability measurement

Relative permeability depending on the numbers of ribbon(a)

and the air gap between ribbons

Relative permeability depending on the number of ribbons for the different air gap between ribbons

Relative permeability depending on the total number of ribbons for the different air gap between ribbons

10 pT

100 pT

1 pT

Noise spectrum of the developed search coil magnetometer

BJne

E xH

1minus=

neRH

1minus=

22 nP micromicro minus

Hall 효과

Bt

IRU H

HL =

2

22

)( he

eh

Hpne

nPR

micromicromicromicro

+

minus=

Rectangular Hall plate (cc1cc2 current constant sc1sc2

sensor constant I bias current U voltage drop UH Hall

voltage

Physics carrier concentration and kind of carrier measurement

Engineering magnetic field measurement

Current Measurement

Arrangement for noninvasive

current measurement using an iron

core The current to be measured

produces a proportional magnetic

field which can be measured in the

air gap

Characteristic curve produced by

the current

Arrangement for indirect noninvasive

current measurement using the

compensation principle An iron core as

represented in Figure 3-29 is held field

free by injection a current into a

compensating coil wound on the core

which offsets the field generated by the

current being measured The Hall effect

sensor in the air gap serves as a null

indicator

Circuit diagram for AC-power

measurement using a Hall effect

sensor

DC Power Measurement

Circuit diagram for DC-

power measurement using a

Hall effect sensor

Noncontact Position Sensing

Galvanomagnetic components for sensing the position of permanent magnets

and magnetically conductive materials

Current Sensor Based on Hall Sensor

and Magnetic Core for Hybrid Vehicle

KH Yeon1 SD Kim1 and D Son2 1Auto industry co14F Hanshin IT tower Guro Gu Seoul Korea2Hannam UniversityOjung dong 133 Daejeon Rep of Korea

i

Hall sensor

B

I

SB

ring core

B

I10

g

N

Bl S

micro

)( gtgtrmicro

gab core

Current Sensor Based on Hall

Sensor and Magnetic Core

Hall

Effect

Device

CurrentVoltage

applying for

Hall effect device

operation

Output

signals

Magnetic field

Occurred by

current measurement

Signal

process

circuits

Developed Current Sensor

Magnetic core

Hall sensor

PCB

25

30

35

40

45

50

Output voltage V

Current sensor(Open loop type)

Temp 25C

400A model

+400 ~ -400A

SD 000128

Linearity 003

Linearity of the sensor

Characteristics of the Current Sensors

1000A 10 V power supply

-500 -400 -300 -200 -100 0 100 200 300 400 500

00

05

10

15

20

Output voltage V

current A

Temperature 25Linearity 003

Measuring range -400A ~ +400A

1000A Electronic Load

-3

0

3

6

9

12

15

18

dB

Current sensor

DV2 PCB 24pF

40Aturns

Frequency bandwidth

Gain bandwidth 3 MHz

Current 10 A

Temperature 25

Frequency bandwidth 100 kHz

Sensor output voltage vs frequency

at applied current of 40 Aturns

1 10 100

-18

-15

-12

-9

-6

Frequency kHz 측정온도 25

주파수특성 30kHz 이상(3dB 기준)

측정전류 40Aturns(4A 10턴)

측정주파수 100Hz ~ 100kHz

Temperature 25Current 40Aturns

Frequency range 100 Hz ~ 100 kHz

What is Magnetoresistance

Magnetoresistance effect(AMR)

θθθ 2cos2

12sin12cos(

22 minusminus+∆asymp∆ xxxmx hhhRR

32 minusasymp∆ ρρ New effect GMR CMR and GMI

10 ge∆ ρρ

Two bridge configuration for

rotational angle measurement

measurement angle more than 180o

자동차 Engine Management System

Inductive and Eddy Current

Sensors Excited by Permanent Magnets

tNtU dd)( φsdotminus=

construction of an inductive

sensor (courtesy VDO Adolf sensor (courtesy VDO Adolf

Schindling AG)

1) constant socket

2) terminal package

3) permanent magnet

4) cap

5) soft magnetic core

6) coil

7) plate

8) blade connector

γγ

Sensor with yoke Change in the magnetic flux with

varying air gap Continuous lines

minimum air gap dashed lines

maximum air gap

C-shaped sensor

Sensor with radially

magnetized

permanent magnet

Signal Conditioning

Output voltage U of a DC-excited sensor with permanent

magnets when a single iron object passes by

Schematic electrical diagram of an inductive sensor

Linear Variable Differential Transformer

AC-Excited Sensors for Linear Movement

Principle of construction of an LVDT

Electrical circuit of an LVDT

tIMtNU dd dd sdotminus=sdotminus= φ

tIMtIMUUU dd dd 1212 sdotminussdot=minus=

tIMMU dd)( 12 sdotminus=

)(12 xMMMM =minus=

tIxMU dd)( sdot= tI

UxM

dd)( =

Signal Conditioning

power supply

carrier gen

autoampcontrol

LVDTcarrieramp

demod-ulator

phase

shifter

power supply

carrier gen

passivedemod-ulator

LVDTDCamp

Block diagram of a carrier amplifier system

Block diagram of a DC amplifier system

Variable Inductive Sensors

Principle of construction

of the VLP sensor

Principle of a bridge

circuit

lANL r 20 sdotsdotsdot= micromicro

21 BA UUU minus=

21)i(ii( 211 minus+sdot= LLLUU BA ωωω

)21))()((( minus∆minus+∆+∆+sdot= LLLLLLUU BA

)212)(( minus∆+sdot= LLLUU )212)(( minus∆+sdot= LLLUU BA

LLUU BA 21 ∆sdotsdot=

llLL ∆sdot=∆ d d

llLLUU BA ∆sdotsdot= d d)2(1

Applications and Properties

Principle of a construction of a force transducer

(courtesy Hottinger Baldwin Messtechnik)

Vibrationacceleration sensor

Signal Conditioning

Schematic electrical diagram of a force transducer connected with an

amplifier (courtesy Hottinger Baldwin Messtechnik GmbH)

Variable Gap Sensors

)( FeFe2

0 LLllANL micromicromicro +sdotsdot=

FeFe2

0max lANL sdotsdotsdot= micromicro

Construction of a variable gap sensor

Characteristic of a variable gap sensor

Construction of a differential

cross-anchor sensor

Output voltage U versus core

position x plusmn a limits of the

linear rage

Applications of differential cross-anchor sensors

AC-excited Sensors for Rotary Movements

Principle of construction of a synchro

α cos10 sdotsdot= UKU y

)120-( cos10 degsdotsdot= αUKU z

)240-( cos10 degsdotsdot= αUKU x

)120-( sin3100 degsdotsdotsdot=minus= αKUUUU yxyx

)240-( sin3100 degsdotsdotsdot=minus= αKUUUU zyzy

α sin3100 sdotsdotsdot=minus= KUUUU xzxz

Application to the Torque Sensor

Principle of construction of a torque-type synchro

Torque versus angular

difference

)( sin~ rt αα minussdotKM

)( cos~ rt1r αα minussdotUU

Principle of construction of a control-type sensor

Output voltage versus

angular difference

Principle of construction of a differential sychro

Eddy Current Sensors

tBE dd curl minus=JH = curl

0 div =BH(H)B sdot= micro

E(E)J sdot= σ

A B curl= A B curl=

tdd- A E =

)dd( tAJ minus= σ

tdd curl curl AA σmicro minus=

AA) σωmicro iminus= curl )(curl(1

AA) σωmicro i=∆)((1

Eddy Current Tachometer

Construction of a speedometer (courtesy VDO Adolf Schinding AG) 1) spindle 2) bearing

3) holding spring 4) iron yoke 5) eddy current cup 6) shaft of the magnet 7) support of

the magnet 8) temperature compensation 9) permanent magnet 10) torsion spring

Proximity Sensors

Schematic diagram of a proximity sensor

Output current of a proximity switch versus distance

Inductive Flowmeters

)( Btimessdot= υqF

EqF sdot=BE times=υ

)(ds Btimes== υEU )(ds Btimes== υEU

)( Bd timessdot= υU

Bsdotsdotsdot= υdKU

Development of magnetic phase detection

sensor for steam generator tube

Dirac Son1 Kwan-Sang Ryu2 Duck-Gun Park3

1Hannam University Daejeon Rep of Korea2Korea Research Institute of Standards and Science Daejeon Rep of Korea3KoreaAtomic Energy Research Institute Daejeon Rep of Korea

Introduction

The layout of pressurized water reactor (PWR) components

Primary side Secondary side (non-radioactive side)(radioactive side)

The Structure of SG(Steam Generator)(degradation mechanism)

Secondary SidePrimary Side

SCC

A B

A-B

Steam outlet

Anti-vibration

SCC

Fretting

Wall thinning

IGA

U-bend

In commercial power plants SG- height up to 21 m - weight up to 800 tons - 2~4 sets of SG were installed - SG can contain from 3000 to

16000 tubes each about 20 mmin diameter

Primary coolant outlet Primary coolant inlet

Anti-vibrationbars

Tubesupportplate

Tubesheet

IGA

SCC

Pitting

SCC

Inside Tubesheet

Top of Tubesheet

by SSHwang of KAERI

Denting

Sludge pile

in diameter

The SGT is made of nickel basedInconel alloy which is composed of 75 Ni 165Cr and 815Fe

-Degradation mechanism corrosion pitting denting inter granular attack

-Inspection Eddy current Testing(ECT)

Permeability Variation Clusters (PVC)

(Ferro-magnetic phase)

-005

000

005

010

015

m (emug)

1-1

-002

000

002

004

006

008

m (emug)

1-2

-1000 -500 0 500 1000

-015

-010

-005

H ( Am )

-1000 -500 0 500 1000

-006

-004

-002

H ( Am )

The hystresis loop in the fragment of PVC parts of Kori-1 retired SG tube

-004

-002

000

002

004

006

M (emug)

Inconel 600 tested at RT

under tensile stress

1 2 3

4 5 6

7 8 9-004

-002

000

002

004

006

M(emug)

Inconel 600 Heat treated at

602 oC under tensile stress

1 2 3

How can we detect magnetic phase

(PVC)selectively from the flaws in SGT

-3000 -2000 -1000 0 1000 2000 3000

-006

H (Oe)

7 8 9

10 11 12

-3000 -2000 -1000 0 1000 2000 3000

-006

-004

H(Oe)

4 5 6

7 8 9

The hysteresis loop of the tensile tested specimen at room temperature (a) and tensile tested at high temperature (b)

The magnetic phase can be created under the high temperature andpressure conditions which is correspond to the stress corrosion crackingin the SG tube in the NPP(Bruemmer SM Charlot LA amp Henager CH (1988) Corrosion 782)

Principle of ECT

If we can separate magnetic phase selectively from the

flaws using magnetic sensor the reliability of EC in SGT

inspection will be greatly enhanced

Structure of the permeability

sensor

Dimension and photograph of U-shape

sensing yoke

Design of Magnetic Sensor for PVC

sensor sensing yoke

Photograph of the completed sensor front side (above) and rear side (bottom)

R11R12

R10

R8

R6

R9

R13

R7

R14

C18

1 n

C17

C20

C21

D2

DIODE

SIN COS

-

+

U-2A

4

13

2

-

+

U-2B

75

6

8

-

+

U-3A

13

2

8

+5VC19

104

+5V

Schematic diagram of the sensor system

Electronic Circuit of Magnetic Sensor

R20

R

R21

R

-

+

U5AD797

3

26

74

U6

D1

S12

GND3

+VCC4VCC5

IN6

-VCC7

S28

C41

R13

R26

R18

R25

R2210 Ω

R16

R14

R17

10 k

R15

R27

R32

R28

R33

R29

R34

5 k

R30

C29

C37

104

C32473

C39473C40

104

C33

104

C21

104C23

104

C25

104

C26

104

C30

104

C31

104

C35

104

C36

104

C27

104

C28

104

C34

104

C38

104

D3

DIODE

L1

1

2

L2

1

2

L3

1

2

4

-

+

U-4A

4

13

2

-

+

U-4B

75

6

8

-

+

U-5A

4

13

2

-

+

U-5B

75

6

8

-

+

U-6A

4

13

2

-

+

U-6B

75

6

8

C22

104

-5V

+5V

+5V

+5V

+5V

+5V

+5V

U7

D1

S12

GND3

+VCC4

VCC5

IN6

-VCC7

S28

+5V

-5V

-5V

-5V

-5V

-5V

-5V

-5V

-5V

R19

R24

R

R23

R

C24

OUT(X)

OUT(Y)

R1

20 kR210 k

R3

20 kR410 k

C1

104

C8

104

REF43

OUT(X)

OUT(Y)

REF43

U2

+Vcc1

CH02

CH13

CH24

CH35

COMM6

SHDN7

Vref8

+Vcc9

GND10

GND11

DOUT12BUSY13DIN14CS15

DIN16

-

+

U-1A

13

2

8

-

+

U-1B

4

75

6

C410 uF

C5104

DOUT

C210uF

C6104

C3104

DCLK

C7104

DIN

C10

01uF

CS

BUSY

C14 10uF

J1

CON6

123456

D1

DIODE

R5

47K

C9

10uF

C1310uF

Y1

OSC

OUT3

GND2

VCC4

U3

RSTVPP1

GND10

VCC20

XTAL15

XTAL24

P10AIN012P11AIN113P1214P1315P1416P1517P1618P1719

P30RXD2

P31TXD3

P32INT06

P33INT17

P34T08

P35T19

P3711

U4

C1+1

C1-3

C2+4

C2-5

VCC16

GND15

V+2

V-6

R1OUT12

R2OUT9

T1IN11

T2IN10

R1IN13

R2IN8

T1OUT14

T2OUT7

C12 10uF

C16

01uF

C15 10uF

C11

01uF

-5V

+5V

+5V

+5V

+5V

+5V

+5V

+5V

RST

OSC

OSC

RST

DCLKCSDINBUSYDOUT

U1

IN2

GND

4

OUT6

TEMP3

TRIM5

-5V

+5V

Electronic circuit diagram of the magnetic sensor

Photograph of the completed measuring system data acquisition

software in PC and probe scanning system

Experimental Setup for Magnetic Sensor

Reference material Scanning System Software LabVIEW

Reference Material (1) Normal defects and PVCs

Longitudinal and transverse defects

Def W L D Remarks

1 02 500 0213 (20 ) Inner defects

2 02 500 0427 (40 )

3 02 500 0213 (20 )Outer defectsPVC(1018)4 02 500 0427 (40 )

5 02 500 0639 (60 )

6 02 500 0852 (80 )

7 02 500 0639 (60 ) Inner defects

8 02 500 0852 (80 )

- 1 and 2 are inner defects

- 345 and 6 are outer defects with PVC

- 7 and 8 are inner defects

PVC

PVC

Defect Defect

For longitudinal defects and PVC For circumferential defects and PVC

ECT is very difficult to detect circumferential defects

We can distinguish PVCs and defects and longitudinal and circumferential defects

Flux-gate Magnetometer

One core sensor Two core sensor

3-축 flux-gate Magnetometer의 계략도

Sensorpia Co

pro

cess

or(

AV

R)

Sensor 1

RS422

Interface

Mic

ro-p

roce

ssor(

AV

R)

Sensor 2

Sensor 3

Interface

조립된 마그네토미터의 사진

Sensorpia Co

Analog PCB

Digital PCB

Sensorpia Co선형도(linearity)

10

20

30

40

50

60

y-axis

Magnetometer Output (microT)

-60 -50 -40 -30 -20 -10 0 10 20 30 40 50 60

-60

-50

-40

-30

-20

-10

0

10

Y-axis y=099946 x+0015STD 106E-4

Magnetometer Output (

Applied Magnetic Field (microT)

마그네토미터의 noise 특성 Sensorpia Co

1

10

100

y-axis

Magnetometer noise (nT)

0 1 2 3 4 5 6

1E-4

1E-3

001

01

Magnetometer noise (nT)

Frequency (Hz)

Magnetometer for KoDSAT

-150 -100 -50 0 50 100 150

-15

-10

-5

0

5

10

15

Magnetic Moment (Am

2)

Current (mA)

After Thermal Cycle Test

Measured

Resistance 193 ohm

Photograph of Magnetic torquer

Photograph of KoDSAT

Photograph of

3-axis Fluxgate

Magnetometer

Photograph of Magnetic torquer

Application of magnetometer

Moon magnetic fieldmeasurement

Telescope with direction indication

Joule Effect (Magnetostriction)

ϕ2cosel

l=

∆

0=∆

+∆

+∆

b

b

a

a

l

l

Actuator using Terfenol-D

00

05

10

B (T)

800

1000

1200

1400

1600

Magnetostriction (ppm)

-100 -50 0 50 100

-10

-05

00

B (T)

H (kAm)

2 MPa

4 MPa

6 MPa

8 MPa

10 MPa

12 MPa

-100 -50 0 50 100

-200

0

200

400

600

Magnetostriction (ppm)

H (kAm)

2 MPa

4 MPa

6 MPa

8 MPa

10 MPa

12 MPa

600

700

800

900

1000

-4 -3 -2 -1 0 1 2 3 4

0

10

20

30

40

50

60

Displacement (m

icro meter)

I (A)

FIELD

9 kAm

12 kAm

16 kAm

20 kAm

24 kAm

38 kAm

-50 -40 -30 -20 -10 0 10 20 30 40 50

-100

0

100

200

300

400

500

L (PPM)

H (kAm)

9 kAm

12 kAm

16 kAm

20 kAm

24 kAm

38 kAm

Magnetostrictive displacement sensor

Hysteresis loops under

tensile stress σ

(a) Crystalline 68 NiFe

λs = +25 10-6

(b) crystalline pure Ni λs

= -35 10-6

Villari Effect ( Inverse of Joule Effect)

= -35 10-6

(c) amorphous Co-based

alloy

λs = -35 10-6

ϕσλ 2sin2

3sdotsdot= smeE

γ

Permeability depending on the stress

σλmicromicro

1

3

2

Y

J

so

s

r =

γ

Calculated magnetization curves under stress

Variation of magnetization curve by an applied

tensile force (Co-based amorphous alloy)

Alloy Requirement

Materials for magnetoelastic sensors

Why amorphous magnetic materials are important

Stress-strain curves of several materials

Coercivity and hardness of several materials

Principles of magnetoelastic sensors

Non-contact torque sensor

Principle of cross torductor torque

sensor and flux pattern of sensor

poles on the surface of a shaft

a) without and b)with torsional load

Equivalent magnetic circuit of

cross type torque sensor

Helices of principal tensile and compressive stress on the surface of

a shaft subjected to torsion [32] Correlated changes of permeability

are detected by four-branch yoke system with sensing coils 123

and 4 and a common excitation pole

Examples of torque sensors

Four-branch type torque sensor

heads Pole structures realized

by commercial multi-pole

ferrites 14 and 18 min in

diameter (diameter of sensor

h e a d 1 7 a n d 2 4 m m

respectively) respectively)

Principle of Ring Torductor torque transducer

(a b) Physical structure (c) evolution of the

shaft surface under the transducer poles A and BRing torductor for measuring

torque on ship propeller shafts

(shaft diameter ca 500 mm)

(Courtesy ASEA Brown

Boveri AG)

Principal designs of coaxial torque sensors

Schematic diagram of data processing

electronics of a torque sensor

Extensometer (a) Construction of strain sensing element using

amorphous ribbon wound core (b) configuration of lumped

windings

∆E effect of an amorphous FeNi-based

alloy (Fe40 Ni38 Mo4 B18) Hs saturation

field

Magnetically tunable delay line

Torque Sensors using Amorphous wire

Sixtus tonk효과(large Barkhausen효과)

Hysteresis loops of a Wiegand wire for different reset fields

Curie 온도 및Hopkinson효과

Relation between normalised

saturation polarisation and

normalised Curie temperature

Permeability of a Mn-Zn ferrite as

a function of temperature and field

strength

Conclusions

1) Magnetic sensor 는 자동차 공장자동화 항공우주 및 군사용으로많이 사용되고 있다

2) 새로운 소재개발은 자기센서의 성능개발에 직접적인 영향을 준다2) 새로운 소재개발은 자기센서의 성능개발에 직접적인 영향을 준다

3) 센서의 개발을 위해서는 다양한 전공지식이 요구된다

(물리학 재료공학 기계공학 전자공학)

4) 센서분야가 고부가가치를 창출하는 부품사업이다

5) 핵심부품을 생산하는 중소기업의 item으로도 적절하다

Minimum noise equivalent magnetic field spectral density of an induction coil sensor with high permeability core versus sensor weight Ws (at length-to-diameter ratios m = 50 and 100 permeability μr = 10000 of the core material and f = 1 Hz)

Induction coil sensors with electronic amplifier

II

rKLC

1=ω

II

II

RR

RK

+=

rr

2 i 1

)(

ωω

ωω

ω

D

KF

+

minus

=

+=

II

II

II

2

C

L

R

R

C

L

KD

Frequency responses of the search coil

Frequency responses of thesensitivity SA and the output voltage UA

of an induction coil sensor with a voltageamplifier at a constant magnetic fieldamplitude

Resonance step-up of thesensitivity SA at differentvalues of the damping D

Sensor with transformer coupled negative feedback to the coil

)(i)()(F

0 ωωωω FR

UMUAU A

A sdot

minus=

)( i1

)(

F

0

ωω

ω

FR

MA

FAUU A

sdot+

sdot=

Induction coil connected to a voltage amplifier with

transformer coupled negative feedback to the coil

FR

21

1K0

i1

1

i1

i )(

ωωωωωω

ωω

+sdot

+sdot=

M

RUU A

IIF2 CRL

MAf

sdotsdotsdotsdot

=∆π

Frequency response of the output voltage UA of an induction coil sensor with negative feedback transformer coupled to the coil

Applications of search coil magnetometer

Developed search coil magnetometer using amorphous ribbon

Experimental setup for the effective permeability measurement

Relative permeability depending on the numbers of ribbon(a)

and the air gap between ribbons

Relative permeability depending on the number of ribbons for the different air gap between ribbons

Relative permeability depending on the total number of ribbons for the different air gap between ribbons

10 pT

100 pT

1 pT

Noise spectrum of the developed search coil magnetometer

BJne

E xH

1minus=

neRH

1minus=

22 nP micromicro minus

Hall 효과

Bt

IRU H

HL =

2

22

)( he

eh

Hpne

nPR

micromicromicromicro

+

minus=

Rectangular Hall plate (cc1cc2 current constant sc1sc2

sensor constant I bias current U voltage drop UH Hall

voltage

Physics carrier concentration and kind of carrier measurement

Engineering magnetic field measurement

Current Measurement

Arrangement for noninvasive

current measurement using an iron

core The current to be measured

produces a proportional magnetic

field which can be measured in the

air gap

Characteristic curve produced by

the current

Arrangement for indirect noninvasive

current measurement using the

compensation principle An iron core as

represented in Figure 3-29 is held field

free by injection a current into a

compensating coil wound on the core

which offsets the field generated by the

current being measured The Hall effect

sensor in the air gap serves as a null

indicator

Circuit diagram for AC-power

measurement using a Hall effect

sensor

DC Power Measurement

Circuit diagram for DC-

power measurement using a

Hall effect sensor

Noncontact Position Sensing

Galvanomagnetic components for sensing the position of permanent magnets

and magnetically conductive materials

Current Sensor Based on Hall Sensor

and Magnetic Core for Hybrid Vehicle

KH Yeon1 SD Kim1 and D Son2 1Auto industry co14F Hanshin IT tower Guro Gu Seoul Korea2Hannam UniversityOjung dong 133 Daejeon Rep of Korea

i

Hall sensor

B

I

SB

ring core

B

I10

g

N

Bl S

micro

)( gtgtrmicro

gab core

Current Sensor Based on Hall

Sensor and Magnetic Core

Hall

Effect

Device

CurrentVoltage

applying for

Hall effect device

operation

Output

signals

Magnetic field

Occurred by

current measurement

Signal

process

circuits

Developed Current Sensor

Magnetic core

Hall sensor

PCB

25

30

35

40

45

50

Output voltage V

Current sensor(Open loop type)

Temp 25C

400A model

+400 ~ -400A

SD 000128

Linearity 003

Linearity of the sensor

Characteristics of the Current Sensors

1000A 10 V power supply

-500 -400 -300 -200 -100 0 100 200 300 400 500

00

05

10

15

20

Output voltage V

current A

Temperature 25Linearity 003

Measuring range -400A ~ +400A

1000A Electronic Load

-3

0

3

6

9

12

15

18

dB

Current sensor

DV2 PCB 24pF

40Aturns

Frequency bandwidth

Gain bandwidth 3 MHz

Current 10 A

Temperature 25

Frequency bandwidth 100 kHz

Sensor output voltage vs frequency

at applied current of 40 Aturns

1 10 100

-18

-15

-12

-9

-6

Frequency kHz 측정온도 25

주파수특성 30kHz 이상(3dB 기준)

측정전류 40Aturns(4A 10턴)

측정주파수 100Hz ~ 100kHz

Temperature 25Current 40Aturns

Frequency range 100 Hz ~ 100 kHz

What is Magnetoresistance

Magnetoresistance effect(AMR)

θθθ 2cos2

12sin12cos(

22 minusminus+∆asymp∆ xxxmx hhhRR

32 minusasymp∆ ρρ New effect GMR CMR and GMI

10 ge∆ ρρ

Two bridge configuration for

rotational angle measurement

measurement angle more than 180o

자동차 Engine Management System

Inductive and Eddy Current

Sensors Excited by Permanent Magnets

tNtU dd)( φsdotminus=

construction of an inductive

sensor (courtesy VDO Adolf sensor (courtesy VDO Adolf

Schindling AG)

1) constant socket

2) terminal package

3) permanent magnet

4) cap

5) soft magnetic core

6) coil

7) plate

8) blade connector

γγ

Sensor with yoke Change in the magnetic flux with

varying air gap Continuous lines

minimum air gap dashed lines

maximum air gap

C-shaped sensor

Sensor with radially

magnetized

permanent magnet

Signal Conditioning

Output voltage U of a DC-excited sensor with permanent

magnets when a single iron object passes by

Schematic electrical diagram of an inductive sensor

Linear Variable Differential Transformer

AC-Excited Sensors for Linear Movement

Principle of construction of an LVDT

Electrical circuit of an LVDT

tIMtNU dd dd sdotminus=sdotminus= φ

tIMtIMUUU dd dd 1212 sdotminussdot=minus=

tIMMU dd)( 12 sdotminus=

)(12 xMMMM =minus=

tIxMU dd)( sdot= tI

UxM

dd)( =

Signal Conditioning

power supply

carrier gen

autoampcontrol

LVDTcarrieramp

demod-ulator

phase

shifter

power supply

carrier gen

passivedemod-ulator

LVDTDCamp

Block diagram of a carrier amplifier system

Block diagram of a DC amplifier system

Variable Inductive Sensors

Principle of construction

of the VLP sensor

Principle of a bridge

circuit

lANL r 20 sdotsdotsdot= micromicro

21 BA UUU minus=

21)i(ii( 211 minus+sdot= LLLUU BA ωωω

)21))()((( minus∆minus+∆+∆+sdot= LLLLLLUU BA

)212)(( minus∆+sdot= LLLUU )212)(( minus∆+sdot= LLLUU BA

LLUU BA 21 ∆sdotsdot=

llLL ∆sdot=∆ d d

llLLUU BA ∆sdotsdot= d d)2(1

Applications and Properties

Principle of a construction of a force transducer

(courtesy Hottinger Baldwin Messtechnik)

Vibrationacceleration sensor

Signal Conditioning

Schematic electrical diagram of a force transducer connected with an

amplifier (courtesy Hottinger Baldwin Messtechnik GmbH)

Variable Gap Sensors

)( FeFe2

0 LLllANL micromicromicro +sdotsdot=

FeFe2

0max lANL sdotsdotsdot= micromicro

Construction of a variable gap sensor

Characteristic of a variable gap sensor

Construction of a differential

cross-anchor sensor

Output voltage U versus core

position x plusmn a limits of the

linear rage

Applications of differential cross-anchor sensors

AC-excited Sensors for Rotary Movements

Principle of construction of a synchro

α cos10 sdotsdot= UKU y

)120-( cos10 degsdotsdot= αUKU z

)240-( cos10 degsdotsdot= αUKU x

)120-( sin3100 degsdotsdotsdot=minus= αKUUUU yxyx

)240-( sin3100 degsdotsdotsdot=minus= αKUUUU zyzy

α sin3100 sdotsdotsdot=minus= KUUUU xzxz

Application to the Torque Sensor

Principle of construction of a torque-type synchro

Torque versus angular

difference

)( sin~ rt αα minussdotKM

)( cos~ rt1r αα minussdotUU

Principle of construction of a control-type sensor

Output voltage versus

angular difference

Principle of construction of a differential sychro

Eddy Current Sensors

tBE dd curl minus=JH = curl

0 div =BH(H)B sdot= micro

E(E)J sdot= σ

A B curl= A B curl=

tdd- A E =

)dd( tAJ minus= σ

tdd curl curl AA σmicro minus=

AA) σωmicro iminus= curl )(curl(1

AA) σωmicro i=∆)((1

Eddy Current Tachometer

Construction of a speedometer (courtesy VDO Adolf Schinding AG) 1) spindle 2) bearing

3) holding spring 4) iron yoke 5) eddy current cup 6) shaft of the magnet 7) support of

the magnet 8) temperature compensation 9) permanent magnet 10) torsion spring

Proximity Sensors

Schematic diagram of a proximity sensor

Output current of a proximity switch versus distance

Inductive Flowmeters

)( Btimessdot= υqF

EqF sdot=BE times=υ

)(ds Btimes== υEU )(ds Btimes== υEU

)( Bd timessdot= υU

Bsdotsdotsdot= υdKU

Development of magnetic phase detection

sensor for steam generator tube

Dirac Son1 Kwan-Sang Ryu2 Duck-Gun Park3

1Hannam University Daejeon Rep of Korea2Korea Research Institute of Standards and Science Daejeon Rep of Korea3KoreaAtomic Energy Research Institute Daejeon Rep of Korea

Introduction

The layout of pressurized water reactor (PWR) components

Primary side Secondary side (non-radioactive side)(radioactive side)

The Structure of SG(Steam Generator)(degradation mechanism)

Secondary SidePrimary Side

SCC

A B

A-B

Steam outlet

Anti-vibration

SCC

Fretting

Wall thinning

IGA

U-bend

In commercial power plants SG- height up to 21 m - weight up to 800 tons - 2~4 sets of SG were installed - SG can contain from 3000 to

16000 tubes each about 20 mmin diameter

Primary coolant outlet Primary coolant inlet

Anti-vibrationbars

Tubesupportplate

Tubesheet

IGA

SCC

Pitting

SCC

Inside Tubesheet

Top of Tubesheet

by SSHwang of KAERI

Denting

Sludge pile

in diameter

The SGT is made of nickel basedInconel alloy which is composed of 75 Ni 165Cr and 815Fe

-Degradation mechanism corrosion pitting denting inter granular attack

-Inspection Eddy current Testing(ECT)

Permeability Variation Clusters (PVC)

(Ferro-magnetic phase)

-005

000

005

010

015

m (emug)

1-1

-002

000

002

004

006

008

m (emug)

1-2

-1000 -500 0 500 1000

-015

-010

-005

H ( Am )

-1000 -500 0 500 1000

-006

-004

-002

H ( Am )

The hystresis loop in the fragment of PVC parts of Kori-1 retired SG tube

-004

-002

000

002

004

006

M (emug)

Inconel 600 tested at RT

under tensile stress

1 2 3

4 5 6

7 8 9-004

-002

000

002

004

006

M(emug)

Inconel 600 Heat treated at

602 oC under tensile stress

1 2 3

How can we detect magnetic phase

(PVC)selectively from the flaws in SGT

-3000 -2000 -1000 0 1000 2000 3000

-006

H (Oe)

7 8 9

10 11 12

-3000 -2000 -1000 0 1000 2000 3000

-006

-004

H(Oe)

4 5 6

7 8 9

The hysteresis loop of the tensile tested specimen at room temperature (a) and tensile tested at high temperature (b)

The magnetic phase can be created under the high temperature andpressure conditions which is correspond to the stress corrosion crackingin the SG tube in the NPP(Bruemmer SM Charlot LA amp Henager CH (1988) Corrosion 782)

Principle of ECT

If we can separate magnetic phase selectively from the

flaws using magnetic sensor the reliability of EC in SGT

inspection will be greatly enhanced

Structure of the permeability

sensor

Dimension and photograph of U-shape

sensing yoke

Design of Magnetic Sensor for PVC

sensor sensing yoke

Photograph of the completed sensor front side (above) and rear side (bottom)

R11R12

R10

R8

R6

R9

R13

R7

R14

C18

1 n

C17

C20

C21

D2

DIODE

SIN COS

-

+

U-2A

4

13

2

-

+

U-2B

75

6

8

-

+

U-3A

13

2

8

+5VC19

104

+5V

Schematic diagram of the sensor system

Electronic Circuit of Magnetic Sensor

R20

R

R21

R

-

+

U5AD797

3

26

74

U6

D1

S12

GND3

+VCC4VCC5

IN6

-VCC7

S28

C41

R13

R26

R18

R25

R2210 Ω

R16

R14

R17

10 k

R15

R27

R32

R28

R33

R29

R34

5 k

R30

C29

C37

104

C32473

C39473C40

104

C33

104

C21

104C23

104

C25

104

C26

104

C30

104

C31

104

C35

104

C36

104

C27

104

C28

104

C34

104

C38

104

D3

DIODE

L1

1

2

L2

1

2

L3

1

2

4

-

+

U-4A

4

13

2

-

+

U-4B

75

6

8

-

+

U-5A

4

13

2

-

+

U-5B

75

6

8

-

+

U-6A

4

13

2

-

+

U-6B

75

6

8

C22

104

-5V

+5V

+5V

+5V

+5V

+5V

+5V

U7

D1

S12

GND3

+VCC4

VCC5

IN6

-VCC7

S28

+5V

-5V

-5V

-5V

-5V

-5V

-5V

-5V

-5V

R19

R24

R

R23

R

C24

OUT(X)

OUT(Y)

R1

20 kR210 k

R3

20 kR410 k

C1

104

C8

104

REF43

OUT(X)

OUT(Y)

REF43

U2

+Vcc1

CH02

CH13

CH24

CH35

COMM6

SHDN7

Vref8

+Vcc9

GND10

GND11

DOUT12BUSY13DIN14CS15

DIN16

-

+

U-1A

13

2

8

-

+

U-1B

4

75

6

C410 uF

C5104

DOUT

C210uF

C6104

C3104

DCLK

C7104

DIN

C10

01uF

CS

BUSY

C14 10uF

J1

CON6

123456

D1

DIODE

R5

47K

C9

10uF

C1310uF

Y1

OSC

OUT3

GND2

VCC4

U3

RSTVPP1

GND10

VCC20

XTAL15

XTAL24

P10AIN012P11AIN113P1214P1315P1416P1517P1618P1719

P30RXD2

P31TXD3

P32INT06

P33INT17

P34T08

P35T19

P3711

U4

C1+1

C1-3

C2+4

C2-5

VCC16

GND15

V+2

V-6

R1OUT12

R2OUT9

T1IN11

T2IN10

R1IN13

R2IN8

T1OUT14

T2OUT7

C12 10uF

C16

01uF

C15 10uF

C11

01uF

-5V

+5V

+5V

+5V

+5V

+5V

+5V

+5V

RST

OSC

OSC

RST

DCLKCSDINBUSYDOUT

U1

IN2

GND

4

OUT6

TEMP3

TRIM5

-5V

+5V

Electronic circuit diagram of the magnetic sensor

Photograph of the completed measuring system data acquisition

software in PC and probe scanning system

Experimental Setup for Magnetic Sensor

Reference material Scanning System Software LabVIEW

Reference Material (1) Normal defects and PVCs

Longitudinal and transverse defects

Def W L D Remarks

1 02 500 0213 (20 ) Inner defects

2 02 500 0427 (40 )

3 02 500 0213 (20 )Outer defectsPVC(1018)4 02 500 0427 (40 )

5 02 500 0639 (60 )

6 02 500 0852 (80 )

7 02 500 0639 (60 ) Inner defects

8 02 500 0852 (80 )

- 1 and 2 are inner defects

- 345 and 6 are outer defects with PVC

- 7 and 8 are inner defects

PVC

PVC

Defect Defect

For longitudinal defects and PVC For circumferential defects and PVC

ECT is very difficult to detect circumferential defects

We can distinguish PVCs and defects and longitudinal and circumferential defects

Flux-gate Magnetometer

One core sensor Two core sensor

3-축 flux-gate Magnetometer의 계략도

Sensorpia Co

pro

cess

or(

AV

R)

Sensor 1

RS422

Interface

Mic

ro-p

roce

ssor(

AV

R)

Sensor 2

Sensor 3

Interface

조립된 마그네토미터의 사진

Sensorpia Co

Analog PCB

Digital PCB

Sensorpia Co선형도(linearity)

10

20

30

40

50

60

y-axis

Magnetometer Output (microT)

-60 -50 -40 -30 -20 -10 0 10 20 30 40 50 60

-60

-50

-40

-30

-20

-10

0

10

Y-axis y=099946 x+0015STD 106E-4

Magnetometer Output (

Applied Magnetic Field (microT)

마그네토미터의 noise 특성 Sensorpia Co

1

10

100

y-axis

Magnetometer noise (nT)

0 1 2 3 4 5 6

1E-4

1E-3

001

01

Magnetometer noise (nT)

Frequency (Hz)

Magnetometer for KoDSAT

-150 -100 -50 0 50 100 150

-15

-10

-5

0

5

10

15

Magnetic Moment (Am

2)

Current (mA)

After Thermal Cycle Test

Measured

Resistance 193 ohm

Photograph of Magnetic torquer

Photograph of KoDSAT

Photograph of

3-axis Fluxgate

Magnetometer

Photograph of Magnetic torquer

Application of magnetometer

Moon magnetic fieldmeasurement

Telescope with direction indication

Joule Effect (Magnetostriction)

ϕ2cosel

l=

∆

0=∆

+∆

+∆

b

b

a

a

l

l

Actuator using Terfenol-D

00

05

10

B (T)

800

1000

1200

1400

1600

Magnetostriction (ppm)

-100 -50 0 50 100

-10

-05

00

B (T)

H (kAm)

2 MPa

4 MPa

6 MPa

8 MPa

10 MPa

12 MPa

-100 -50 0 50 100

-200

0

200

400

600

Magnetostriction (ppm)

H (kAm)

2 MPa

4 MPa

6 MPa

8 MPa

10 MPa

12 MPa

600

700

800

900

1000

-4 -3 -2 -1 0 1 2 3 4

0

10

20

30

40

50

60

Displacement (m

icro meter)

I (A)

FIELD

9 kAm

12 kAm

16 kAm

20 kAm

24 kAm

38 kAm

-50 -40 -30 -20 -10 0 10 20 30 40 50

-100

0

100

200

300

400

500

L (PPM)

H (kAm)

9 kAm

12 kAm

16 kAm

20 kAm

24 kAm

38 kAm

Magnetostrictive displacement sensor

Hysteresis loops under

tensile stress σ

(a) Crystalline 68 NiFe

λs = +25 10-6

(b) crystalline pure Ni λs

= -35 10-6

Villari Effect ( Inverse of Joule Effect)

= -35 10-6

(c) amorphous Co-based

alloy

λs = -35 10-6

ϕσλ 2sin2

3sdotsdot= smeE

γ

Permeability depending on the stress

σλmicromicro

1

3

2

Y

J

so

s

r =

γ

Calculated magnetization curves under stress

Variation of magnetization curve by an applied

tensile force (Co-based amorphous alloy)

Alloy Requirement

Materials for magnetoelastic sensors

Why amorphous magnetic materials are important

Stress-strain curves of several materials

Coercivity and hardness of several materials

Principles of magnetoelastic sensors

Non-contact torque sensor

Principle of cross torductor torque

sensor and flux pattern of sensor

poles on the surface of a shaft

a) without and b)with torsional load

Equivalent magnetic circuit of

cross type torque sensor

Helices of principal tensile and compressive stress on the surface of

a shaft subjected to torsion [32] Correlated changes of permeability

are detected by four-branch yoke system with sensing coils 123

and 4 and a common excitation pole

Examples of torque sensors

Four-branch type torque sensor

heads Pole structures realized

by commercial multi-pole

ferrites 14 and 18 min in

diameter (diameter of sensor

h e a d 1 7 a n d 2 4 m m

respectively) respectively)

Principle of Ring Torductor torque transducer

(a b) Physical structure (c) evolution of the

shaft surface under the transducer poles A and BRing torductor for measuring

torque on ship propeller shafts

(shaft diameter ca 500 mm)

(Courtesy ASEA Brown

Boveri AG)

Principal designs of coaxial torque sensors

Schematic diagram of data processing

electronics of a torque sensor

Extensometer (a) Construction of strain sensing element using

amorphous ribbon wound core (b) configuration of lumped

windings

∆E effect of an amorphous FeNi-based

alloy (Fe40 Ni38 Mo4 B18) Hs saturation

field

Magnetically tunable delay line

Torque Sensors using Amorphous wire

Sixtus tonk효과(large Barkhausen효과)

Hysteresis loops of a Wiegand wire for different reset fields

Curie 온도 및Hopkinson효과

Relation between normalised

saturation polarisation and

normalised Curie temperature

Permeability of a Mn-Zn ferrite as

a function of temperature and field

strength

Conclusions

1) Magnetic sensor 는 자동차 공장자동화 항공우주 및 군사용으로많이 사용되고 있다

2) 새로운 소재개발은 자기센서의 성능개발에 직접적인 영향을 준다2) 새로운 소재개발은 자기센서의 성능개발에 직접적인 영향을 준다

3) 센서의 개발을 위해서는 다양한 전공지식이 요구된다

(물리학 재료공학 기계공학 전자공학)

4) 센서분야가 고부가가치를 창출하는 부품사업이다

5) 핵심부품을 생산하는 중소기업의 item으로도 적절하다

Induction coil sensors with electronic amplifier

II

rKLC

1=ω

II

II

RR

RK

+=

rr

2 i 1

)(

ωω

ωω

ω

D

KF

+

minus

=

+=

II

II

II

2

C

L

R

R

C

L

KD

Frequency responses of the search coil

Frequency responses of thesensitivity SA and the output voltage UA

of an induction coil sensor with a voltageamplifier at a constant magnetic fieldamplitude

Resonance step-up of thesensitivity SA at differentvalues of the damping D

Sensor with transformer coupled negative feedback to the coil

)(i)()(F

0 ωωωω FR

UMUAU A

A sdot

minus=

)( i1

)(

F

0

ωω

ω

FR

MA

FAUU A

sdot+

sdot=

Induction coil connected to a voltage amplifier with

transformer coupled negative feedback to the coil

FR

21

1K0

i1

1

i1

i )(

ωωωωωω

ωω

+sdot

+sdot=

M

RUU A

IIF2 CRL

MAf

sdotsdotsdotsdot

=∆π

Frequency response of the output voltage UA of an induction coil sensor with negative feedback transformer coupled to the coil

Applications of search coil magnetometer

Developed search coil magnetometer using amorphous ribbon

Experimental setup for the effective permeability measurement

Relative permeability depending on the numbers of ribbon(a)

and the air gap between ribbons

Relative permeability depending on the number of ribbons for the different air gap between ribbons

Relative permeability depending on the total number of ribbons for the different air gap between ribbons

10 pT

100 pT

1 pT

Noise spectrum of the developed search coil magnetometer

BJne

E xH

1minus=

neRH

1minus=

22 nP micromicro minus

Hall 효과

Bt

IRU H

HL =

2

22

)( he

eh

Hpne

nPR

micromicromicromicro

+

minus=

Rectangular Hall plate (cc1cc2 current constant sc1sc2

sensor constant I bias current U voltage drop UH Hall

voltage

Physics carrier concentration and kind of carrier measurement

Engineering magnetic field measurement

Current Measurement

Arrangement for noninvasive

current measurement using an iron

core The current to be measured

produces a proportional magnetic

field which can be measured in the

air gap

Characteristic curve produced by

the current

Arrangement for indirect noninvasive

current measurement using the

compensation principle An iron core as

represented in Figure 3-29 is held field

free by injection a current into a

compensating coil wound on the core

which offsets the field generated by the

current being measured The Hall effect

sensor in the air gap serves as a null

indicator

Circuit diagram for AC-power

measurement using a Hall effect

sensor

DC Power Measurement

Circuit diagram for DC-

power measurement using a

Hall effect sensor

Noncontact Position Sensing

Galvanomagnetic components for sensing the position of permanent magnets

and magnetically conductive materials

Current Sensor Based on Hall Sensor

and Magnetic Core for Hybrid Vehicle

KH Yeon1 SD Kim1 and D Son2 1Auto industry co14F Hanshin IT tower Guro Gu Seoul Korea2Hannam UniversityOjung dong 133 Daejeon Rep of Korea

i

Hall sensor

B

I

SB

ring core

B

I10

g

N

Bl S

micro

)( gtgtrmicro

gab core

Current Sensor Based on Hall

Sensor and Magnetic Core

Hall

Effect

Device

CurrentVoltage

applying for

Hall effect device

operation

Output

signals

Magnetic field

Occurred by

current measurement

Signal

process

circuits

Developed Current Sensor

Magnetic core

Hall sensor

PCB

25

30

35

40

45

50

Output voltage V

Current sensor(Open loop type)

Temp 25C

400A model

+400 ~ -400A

SD 000128

Linearity 003

Linearity of the sensor

Characteristics of the Current Sensors

1000A 10 V power supply

-500 -400 -300 -200 -100 0 100 200 300 400 500

00

05

10

15

20

Output voltage V

current A

Temperature 25Linearity 003

Measuring range -400A ~ +400A

1000A Electronic Load

-3

0

3

6

9

12

15

18

dB

Current sensor

DV2 PCB 24pF

40Aturns

Frequency bandwidth

Gain bandwidth 3 MHz

Current 10 A

Temperature 25

Frequency bandwidth 100 kHz

Sensor output voltage vs frequency

at applied current of 40 Aturns

1 10 100

-18

-15

-12

-9

-6

Frequency kHz 측정온도 25

주파수특성 30kHz 이상(3dB 기준)

측정전류 40Aturns(4A 10턴)

측정주파수 100Hz ~ 100kHz

Temperature 25Current 40Aturns

Frequency range 100 Hz ~ 100 kHz

What is Magnetoresistance

Magnetoresistance effect(AMR)

θθθ 2cos2

12sin12cos(

22 minusminus+∆asymp∆ xxxmx hhhRR

32 minusasymp∆ ρρ New effect GMR CMR and GMI

10 ge∆ ρρ

Two bridge configuration for

rotational angle measurement

measurement angle more than 180o

자동차 Engine Management System

Inductive and Eddy Current

Sensors Excited by Permanent Magnets

tNtU dd)( φsdotminus=

construction of an inductive

sensor (courtesy VDO Adolf sensor (courtesy VDO Adolf

Schindling AG)

1) constant socket

2) terminal package

3) permanent magnet

4) cap

5) soft magnetic core

6) coil

7) plate

8) blade connector

γγ

Sensor with yoke Change in the magnetic flux with

varying air gap Continuous lines

minimum air gap dashed lines

maximum air gap

C-shaped sensor

Sensor with radially

magnetized

permanent magnet

Signal Conditioning

Output voltage U of a DC-excited sensor with permanent

magnets when a single iron object passes by

Schematic electrical diagram of an inductive sensor

Linear Variable Differential Transformer

AC-Excited Sensors for Linear Movement

Principle of construction of an LVDT

Electrical circuit of an LVDT

tIMtNU dd dd sdotminus=sdotminus= φ

tIMtIMUUU dd dd 1212 sdotminussdot=minus=

tIMMU dd)( 12 sdotminus=

)(12 xMMMM =minus=

tIxMU dd)( sdot= tI

UxM

dd)( =

Signal Conditioning

power supply

carrier gen

autoampcontrol

LVDTcarrieramp

demod-ulator

phase

shifter

power supply

carrier gen

passivedemod-ulator

LVDTDCamp

Block diagram of a carrier amplifier system

Block diagram of a DC amplifier system

Variable Inductive Sensors

Principle of construction

of the VLP sensor

Principle of a bridge

circuit

lANL r 20 sdotsdotsdot= micromicro

21 BA UUU minus=

21)i(ii( 211 minus+sdot= LLLUU BA ωωω

)21))()((( minus∆minus+∆+∆+sdot= LLLLLLUU BA

)212)(( minus∆+sdot= LLLUU )212)(( minus∆+sdot= LLLUU BA

LLUU BA 21 ∆sdotsdot=

llLL ∆sdot=∆ d d

llLLUU BA ∆sdotsdot= d d)2(1

Applications and Properties

Principle of a construction of a force transducer

(courtesy Hottinger Baldwin Messtechnik)

Vibrationacceleration sensor

Signal Conditioning

Schematic electrical diagram of a force transducer connected with an

amplifier (courtesy Hottinger Baldwin Messtechnik GmbH)

Variable Gap Sensors

)( FeFe2

0 LLllANL micromicromicro +sdotsdot=

FeFe2

0max lANL sdotsdotsdot= micromicro

Construction of a variable gap sensor

Characteristic of a variable gap sensor

Construction of a differential

cross-anchor sensor

Output voltage U versus core

position x plusmn a limits of the

linear rage

Applications of differential cross-anchor sensors

AC-excited Sensors for Rotary Movements

Principle of construction of a synchro

α cos10 sdotsdot= UKU y

)120-( cos10 degsdotsdot= αUKU z

)240-( cos10 degsdotsdot= αUKU x

)120-( sin3100 degsdotsdotsdot=minus= αKUUUU yxyx

)240-( sin3100 degsdotsdotsdot=minus= αKUUUU zyzy

α sin3100 sdotsdotsdot=minus= KUUUU xzxz

Application to the Torque Sensor

Principle of construction of a torque-type synchro

Torque versus angular

difference

)( sin~ rt αα minussdotKM

)( cos~ rt1r αα minussdotUU

Principle of construction of a control-type sensor

Output voltage versus

angular difference

Principle of construction of a differential sychro

Eddy Current Sensors

tBE dd curl minus=JH = curl

0 div =BH(H)B sdot= micro

E(E)J sdot= σ

A B curl= A B curl=

tdd- A E =

)dd( tAJ minus= σ

tdd curl curl AA σmicro minus=

AA) σωmicro iminus= curl )(curl(1

AA) σωmicro i=∆)((1

Eddy Current Tachometer

Construction of a speedometer (courtesy VDO Adolf Schinding AG) 1) spindle 2) bearing

3) holding spring 4) iron yoke 5) eddy current cup 6) shaft of the magnet 7) support of

the magnet 8) temperature compensation 9) permanent magnet 10) torsion spring

Proximity Sensors

Schematic diagram of a proximity sensor

Output current of a proximity switch versus distance

Inductive Flowmeters

)( Btimessdot= υqF

EqF sdot=BE times=υ

)(ds Btimes== υEU )(ds Btimes== υEU

)( Bd timessdot= υU

Bsdotsdotsdot= υdKU

Development of magnetic phase detection

sensor for steam generator tube

Dirac Son1 Kwan-Sang Ryu2 Duck-Gun Park3

1Hannam University Daejeon Rep of Korea2Korea Research Institute of Standards and Science Daejeon Rep of Korea3KoreaAtomic Energy Research Institute Daejeon Rep of Korea

Introduction

The layout of pressurized water reactor (PWR) components

Primary side Secondary side (non-radioactive side)(radioactive side)

The Structure of SG(Steam Generator)(degradation mechanism)

Secondary SidePrimary Side

SCC

A B

A-B

Steam outlet

Anti-vibration

SCC

Fretting

Wall thinning

IGA

U-bend

In commercial power plants SG- height up to 21 m - weight up to 800 tons - 2~4 sets of SG were installed - SG can contain from 3000 to

16000 tubes each about 20 mmin diameter

Primary coolant outlet Primary coolant inlet

Anti-vibrationbars

Tubesupportplate

Tubesheet

IGA

SCC

Pitting

SCC

Inside Tubesheet

Top of Tubesheet

by SSHwang of KAERI

Denting

Sludge pile

in diameter

The SGT is made of nickel basedInconel alloy which is composed of 75 Ni 165Cr and 815Fe

-Degradation mechanism corrosion pitting denting inter granular attack

-Inspection Eddy current Testing(ECT)

Permeability Variation Clusters (PVC)

(Ferro-magnetic phase)

-005

000

005

010

015

m (emug)

1-1

-002

000

002

004

006

008

m (emug)

1-2

-1000 -500 0 500 1000

-015

-010

-005

H ( Am )

-1000 -500 0 500 1000

-006

-004

-002

H ( Am )

The hystresis loop in the fragment of PVC parts of Kori-1 retired SG tube

-004

-002

000

002

004

006

M (emug)

Inconel 600 tested at RT

under tensile stress

1 2 3

4 5 6

7 8 9-004

-002

000

002

004

006

M(emug)

Inconel 600 Heat treated at

602 oC under tensile stress

1 2 3

How can we detect magnetic phase

(PVC)selectively from the flaws in SGT

-3000 -2000 -1000 0 1000 2000 3000

-006

H (Oe)

7 8 9

10 11 12

-3000 -2000 -1000 0 1000 2000 3000

-006

-004

H(Oe)

4 5 6

7 8 9

The hysteresis loop of the tensile tested specimen at room temperature (a) and tensile tested at high temperature (b)

The magnetic phase can be created under the high temperature andpressure conditions which is correspond to the stress corrosion crackingin the SG tube in the NPP(Bruemmer SM Charlot LA amp Henager CH (1988) Corrosion 782)

Principle of ECT

If we can separate magnetic phase selectively from the

flaws using magnetic sensor the reliability of EC in SGT

inspection will be greatly enhanced

Structure of the permeability

sensor

Dimension and photograph of U-shape

sensing yoke

Design of Magnetic Sensor for PVC

sensor sensing yoke

Photograph of the completed sensor front side (above) and rear side (bottom)

R11R12

R10

R8

R6

R9

R13

R7

R14

C18

1 n

C17

C20

C21

D2

DIODE

SIN COS

-

+

U-2A

4

13

2

-

+

U-2B

75

6

8

-

+

U-3A

13

2

8

+5VC19

104

+5V

Schematic diagram of the sensor system

Electronic Circuit of Magnetic Sensor

R20

R

R21

R

-

+

U5AD797

3

26

74

U6

D1

S12

GND3

+VCC4VCC5

IN6

-VCC7

S28

C41

R13

R26

R18

R25

R2210 Ω

R16

R14

R17

10 k

R15

R27

R32

R28

R33

R29

R34

5 k

R30

C29

C37

104

C32473

C39473C40

104

C33

104

C21

104C23

104

C25

104

C26

104

C30

104

C31

104

C35

104

C36

104

C27

104

C28

104

C34

104

C38

104

D3

DIODE

L1

1

2

L2

1

2

L3

1

2

4

-

+

U-4A

4

13

2

-

+

U-4B

75

6

8

-

+

U-5A

4

13

2

-

+

U-5B

75

6

8

-

+

U-6A

4

13

2

-

+

U-6B

75

6

8

C22

104

-5V

+5V

+5V

+5V

+5V

+5V

+5V

U7

D1

S12

GND3

+VCC4

VCC5

IN6

-VCC7

S28

+5V

-5V

-5V

-5V

-5V

-5V

-5V

-5V

-5V

R19

R24

R

R23

R

C24

OUT(X)

OUT(Y)

R1

20 kR210 k

R3

20 kR410 k

C1

104

C8

104

REF43

OUT(X)

OUT(Y)

REF43

U2

+Vcc1

CH02

CH13

CH24

CH35

COMM6

SHDN7

Vref8

+Vcc9

GND10

GND11

DOUT12BUSY13DIN14CS15

DIN16

-

+

U-1A

13

2

8

-

+

U-1B

4

75

6

C410 uF

C5104

DOUT

C210uF

C6104

C3104

DCLK

C7104

DIN

C10

01uF

CS

BUSY

C14 10uF

J1

CON6

123456

D1

DIODE

R5

47K

C9

10uF

C1310uF

Y1

OSC

OUT3

GND2

VCC4

U3

RSTVPP1

GND10

VCC20

XTAL15

XTAL24

P10AIN012P11AIN113P1214P1315P1416P1517P1618P1719

P30RXD2

P31TXD3

P32INT06

P33INT17

P34T08

P35T19

P3711

U4

C1+1

C1-3

C2+4

C2-5

VCC16

GND15

V+2

V-6

R1OUT12

R2OUT9

T1IN11

T2IN10

R1IN13

R2IN8

T1OUT14

T2OUT7

C12 10uF

C16

01uF

C15 10uF

C11

01uF

-5V

+5V

+5V

+5V

+5V

+5V

+5V

+5V

RST

OSC

OSC

RST

DCLKCSDINBUSYDOUT

U1

IN2

GND

4

OUT6

TEMP3

TRIM5

-5V

+5V

Electronic circuit diagram of the magnetic sensor

Photograph of the completed measuring system data acquisition

software in PC and probe scanning system

Experimental Setup for Magnetic Sensor

Reference material Scanning System Software LabVIEW

Reference Material (1) Normal defects and PVCs

Longitudinal and transverse defects

Def W L D Remarks

1 02 500 0213 (20 ) Inner defects

2 02 500 0427 (40 )

3 02 500 0213 (20 )Outer defectsPVC(1018)4 02 500 0427 (40 )

5 02 500 0639 (60 )

6 02 500 0852 (80 )

7 02 500 0639 (60 ) Inner defects

8 02 500 0852 (80 )

- 1 and 2 are inner defects

- 345 and 6 are outer defects with PVC

- 7 and 8 are inner defects

PVC

PVC

Defect Defect

For longitudinal defects and PVC For circumferential defects and PVC

ECT is very difficult to detect circumferential defects

We can distinguish PVCs and defects and longitudinal and circumferential defects

Flux-gate Magnetometer

One core sensor Two core sensor

3-축 flux-gate Magnetometer의 계략도

Sensorpia Co

pro

cess

or(

AV

R)

Sensor 1

RS422

Interface

Mic

ro-p

roce

ssor(

AV

R)

Sensor 2

Sensor 3

Interface

조립된 마그네토미터의 사진

Sensorpia Co

Analog PCB

Digital PCB

Sensorpia Co선형도(linearity)

10

20

30

40

50

60

y-axis

Magnetometer Output (microT)

-60 -50 -40 -30 -20 -10 0 10 20 30 40 50 60

-60

-50

-40

-30

-20

-10

0

10

Y-axis y=099946 x+0015STD 106E-4

Magnetometer Output (

Applied Magnetic Field (microT)

마그네토미터의 noise 특성 Sensorpia Co

1

10

100

y-axis

Magnetometer noise (nT)

0 1 2 3 4 5 6

1E-4

1E-3

001

01

Magnetometer noise (nT)

Frequency (Hz)

Magnetometer for KoDSAT

-150 -100 -50 0 50 100 150

-15

-10

-5

0

5

10

15

Magnetic Moment (Am

2)

Current (mA)

After Thermal Cycle Test

Measured

Resistance 193 ohm

Photograph of Magnetic torquer

Photograph of KoDSAT

Photograph of

3-axis Fluxgate

Magnetometer

Photograph of Magnetic torquer

Application of magnetometer

Moon magnetic fieldmeasurement

Telescope with direction indication

Joule Effect (Magnetostriction)

ϕ2cosel

l=

∆

0=∆

+∆

+∆

b

b

a

a

l

l

Actuator using Terfenol-D

00

05

10

B (T)

800

1000

1200

1400

1600

Magnetostriction (ppm)

-100 -50 0 50 100

-10

-05

00

B (T)

H (kAm)

2 MPa

4 MPa

6 MPa

8 MPa

10 MPa

12 MPa

-100 -50 0 50 100

-200

0

200

400

600

Magnetostriction (ppm)

H (kAm)

2 MPa

4 MPa

6 MPa

8 MPa

10 MPa

12 MPa

600

700

800

900

1000

-4 -3 -2 -1 0 1 2 3 4

0

10

20

30

40

50

60

Displacement (m

icro meter)

I (A)

FIELD

9 kAm

12 kAm

16 kAm

20 kAm

24 kAm

38 kAm

-50 -40 -30 -20 -10 0 10 20 30 40 50

-100

0

100

200

300

400

500

L (PPM)

H (kAm)

9 kAm

12 kAm

16 kAm

20 kAm

24 kAm

38 kAm

Magnetostrictive displacement sensor

Hysteresis loops under

tensile stress σ

(a) Crystalline 68 NiFe

λs = +25 10-6

(b) crystalline pure Ni λs

= -35 10-6

Villari Effect ( Inverse of Joule Effect)

= -35 10-6

(c) amorphous Co-based

alloy

λs = -35 10-6

ϕσλ 2sin2

3sdotsdot= smeE

γ

Permeability depending on the stress

σλmicromicro

1

3

2

Y

J

so

s

r =

γ

Calculated magnetization curves under stress

Variation of magnetization curve by an applied

tensile force (Co-based amorphous alloy)

Alloy Requirement

Materials for magnetoelastic sensors

Why amorphous magnetic materials are important

Stress-strain curves of several materials

Coercivity and hardness of several materials

Principles of magnetoelastic sensors

Non-contact torque sensor

Principle of cross torductor torque

sensor and flux pattern of sensor

poles on the surface of a shaft

a) without and b)with torsional load

Equivalent magnetic circuit of

cross type torque sensor

Helices of principal tensile and compressive stress on the surface of

a shaft subjected to torsion [32] Correlated changes of permeability

are detected by four-branch yoke system with sensing coils 123

and 4 and a common excitation pole

Examples of torque sensors

Four-branch type torque sensor

heads Pole structures realized

by commercial multi-pole

ferrites 14 and 18 min in

diameter (diameter of sensor

h e a d 1 7 a n d 2 4 m m

respectively) respectively)

Principle of Ring Torductor torque transducer

(a b) Physical structure (c) evolution of the

shaft surface under the transducer poles A and BRing torductor for measuring

torque on ship propeller shafts

(shaft diameter ca 500 mm)

(Courtesy ASEA Brown

Boveri AG)

Principal designs of coaxial torque sensors

Schematic diagram of data processing

electronics of a torque sensor

Extensometer (a) Construction of strain sensing element using

amorphous ribbon wound core (b) configuration of lumped

windings

∆E effect of an amorphous FeNi-based

alloy (Fe40 Ni38 Mo4 B18) Hs saturation

field

Magnetically tunable delay line

Torque Sensors using Amorphous wire

Sixtus tonk효과(large Barkhausen효과)

Hysteresis loops of a Wiegand wire for different reset fields

Curie 온도 및Hopkinson효과

Relation between normalised

saturation polarisation and

normalised Curie temperature

Permeability of a Mn-Zn ferrite as

a function of temperature and field

strength

Conclusions

1) Magnetic sensor 는 자동차 공장자동화 항공우주 및 군사용으로많이 사용되고 있다

2) 새로운 소재개발은 자기센서의 성능개발에 직접적인 영향을 준다2) 새로운 소재개발은 자기센서의 성능개발에 직접적인 영향을 준다

3) 센서의 개발을 위해서는 다양한 전공지식이 요구된다

(물리학 재료공학 기계공학 전자공학)

4) 센서분야가 고부가가치를 창출하는 부품사업이다

5) 핵심부품을 생산하는 중소기업의 item으로도 적절하다

Frequency responses of the search coil

Frequency responses of thesensitivity SA and the output voltage UA

of an induction coil sensor with a voltageamplifier at a constant magnetic fieldamplitude

Resonance step-up of thesensitivity SA at differentvalues of the damping D

Sensor with transformer coupled negative feedback to the coil

)(i)()(F

0 ωωωω FR

UMUAU A

A sdot

minus=

)( i1

)(

F

0

ωω

ω

FR

MA

FAUU A

sdot+

sdot=

Induction coil connected to a voltage amplifier with

transformer coupled negative feedback to the coil

FR

21

1K0

i1

1

i1

i )(

ωωωωωω

ωω

+sdot

+sdot=

M

RUU A

IIF2 CRL

MAf

sdotsdotsdotsdot

=∆π

Frequency response of the output voltage UA of an induction coil sensor with negative feedback transformer coupled to the coil

Applications of search coil magnetometer

Developed search coil magnetometer using amorphous ribbon

Experimental setup for the effective permeability measurement

Relative permeability depending on the numbers of ribbon(a)

and the air gap between ribbons

Relative permeability depending on the number of ribbons for the different air gap between ribbons

Relative permeability depending on the total number of ribbons for the different air gap between ribbons

10 pT

100 pT

1 pT

Noise spectrum of the developed search coil magnetometer

BJne

E xH

1minus=

neRH

1minus=

22 nP micromicro minus

Hall 효과

Bt

IRU H

HL =

2

22

)( he

eh

Hpne

nPR

micromicromicromicro

+

minus=

Rectangular Hall plate (cc1cc2 current constant sc1sc2

sensor constant I bias current U voltage drop UH Hall

voltage

Physics carrier concentration and kind of carrier measurement

Engineering magnetic field measurement

Current Measurement

Arrangement for noninvasive

current measurement using an iron

core The current to be measured

produces a proportional magnetic

field which can be measured in the

air gap

Characteristic curve produced by

the current

Arrangement for indirect noninvasive

current measurement using the

compensation principle An iron core as

represented in Figure 3-29 is held field

free by injection a current into a

compensating coil wound on the core

which offsets the field generated by the

current being measured The Hall effect

sensor in the air gap serves as a null

indicator

Circuit diagram for AC-power

measurement using a Hall effect

sensor

DC Power Measurement

Circuit diagram for DC-

power measurement using a

Hall effect sensor

Noncontact Position Sensing

Galvanomagnetic components for sensing the position of permanent magnets

and magnetically conductive materials

Current Sensor Based on Hall Sensor

and Magnetic Core for Hybrid Vehicle

KH Yeon1 SD Kim1 and D Son2 1Auto industry co14F Hanshin IT tower Guro Gu Seoul Korea2Hannam UniversityOjung dong 133 Daejeon Rep of Korea

i

Hall sensor

B

I

SB

ring core

B

I10

g

N

Bl S

micro

)( gtgtrmicro

gab core

Current Sensor Based on Hall

Sensor and Magnetic Core

Hall

Effect

Device

CurrentVoltage

applying for

Hall effect device

operation

Output

signals

Magnetic field

Occurred by

current measurement

Signal

process

circuits

Developed Current Sensor

Magnetic core

Hall sensor

PCB

25

30

35

40

45

50

Output voltage V

Current sensor(Open loop type)

Temp 25C

400A model

+400 ~ -400A

SD 000128

Linearity 003

Linearity of the sensor

Characteristics of the Current Sensors

1000A 10 V power supply

-500 -400 -300 -200 -100 0 100 200 300 400 500

00

05

10

15

20

Output voltage V

current A

Temperature 25Linearity 003

Measuring range -400A ~ +400A

1000A Electronic Load

-3

0

3

6

9

12

15

18

dB

Current sensor

DV2 PCB 24pF

40Aturns

Frequency bandwidth

Gain bandwidth 3 MHz

Current 10 A

Temperature 25

Frequency bandwidth 100 kHz

Sensor output voltage vs frequency

at applied current of 40 Aturns

1 10 100

-18

-15

-12

-9

-6

Frequency kHz 측정온도 25

주파수특성 30kHz 이상(3dB 기준)

측정전류 40Aturns(4A 10턴)

측정주파수 100Hz ~ 100kHz

Temperature 25Current 40Aturns

Frequency range 100 Hz ~ 100 kHz

What is Magnetoresistance

Magnetoresistance effect(AMR)

θθθ 2cos2

12sin12cos(

22 minusminus+∆asymp∆ xxxmx hhhRR

32 minusasymp∆ ρρ New effect GMR CMR and GMI

10 ge∆ ρρ

Two bridge configuration for

rotational angle measurement

measurement angle more than 180o

자동차 Engine Management System

Inductive and Eddy Current

Sensors Excited by Permanent Magnets

tNtU dd)( φsdotminus=

construction of an inductive

sensor (courtesy VDO Adolf sensor (courtesy VDO Adolf

Schindling AG)

1) constant socket

2) terminal package

3) permanent magnet

4) cap

5) soft magnetic core

6) coil

7) plate

8) blade connector

γγ

Sensor with yoke Change in the magnetic flux with

varying air gap Continuous lines

minimum air gap dashed lines

maximum air gap

C-shaped sensor

Sensor with radially

magnetized

permanent magnet

Signal Conditioning

Output voltage U of a DC-excited sensor with permanent

magnets when a single iron object passes by

Schematic electrical diagram of an inductive sensor

Linear Variable Differential Transformer

AC-Excited Sensors for Linear Movement

Principle of construction of an LVDT

Electrical circuit of an LVDT

tIMtNU dd dd sdotminus=sdotminus= φ

tIMtIMUUU dd dd 1212 sdotminussdot=minus=

tIMMU dd)( 12 sdotminus=

)(12 xMMMM =minus=

tIxMU dd)( sdot= tI

UxM

dd)( =

Signal Conditioning

power supply

carrier gen

autoampcontrol

LVDTcarrieramp

demod-ulator

phase

shifter

power supply

carrier gen

passivedemod-ulator

LVDTDCamp

Block diagram of a carrier amplifier system

Block diagram of a DC amplifier system

Variable Inductive Sensors

Principle of construction

of the VLP sensor

Principle of a bridge

circuit

lANL r 20 sdotsdotsdot= micromicro

21 BA UUU minus=

21)i(ii( 211 minus+sdot= LLLUU BA ωωω

)21))()((( minus∆minus+∆+∆+sdot= LLLLLLUU BA

)212)(( minus∆+sdot= LLLUU )212)(( minus∆+sdot= LLLUU BA

LLUU BA 21 ∆sdotsdot=

llLL ∆sdot=∆ d d

llLLUU BA ∆sdotsdot= d d)2(1

Applications and Properties

Principle of a construction of a force transducer

(courtesy Hottinger Baldwin Messtechnik)

Vibrationacceleration sensor

Signal Conditioning

Schematic electrical diagram of a force transducer connected with an

amplifier (courtesy Hottinger Baldwin Messtechnik GmbH)

Variable Gap Sensors

)( FeFe2

0 LLllANL micromicromicro +sdotsdot=

FeFe2

0max lANL sdotsdotsdot= micromicro

Construction of a variable gap sensor

Characteristic of a variable gap sensor

Construction of a differential

cross-anchor sensor

Output voltage U versus core

position x plusmn a limits of the

linear rage

Applications of differential cross-anchor sensors

AC-excited Sensors for Rotary Movements

Principle of construction of a synchro

α cos10 sdotsdot= UKU y

)120-( cos10 degsdotsdot= αUKU z

)240-( cos10 degsdotsdot= αUKU x

)120-( sin3100 degsdotsdotsdot=minus= αKUUUU yxyx

)240-( sin3100 degsdotsdotsdot=minus= αKUUUU zyzy

α sin3100 sdotsdotsdot=minus= KUUUU xzxz

Application to the Torque Sensor

Principle of construction of a torque-type synchro

Torque versus angular

difference

)( sin~ rt αα minussdotKM

)( cos~ rt1r αα minussdotUU

Principle of construction of a control-type sensor

Output voltage versus

angular difference

Principle of construction of a differential sychro

Eddy Current Sensors

tBE dd curl minus=JH = curl

0 div =BH(H)B sdot= micro

E(E)J sdot= σ

A B curl= A B curl=

tdd- A E =

)dd( tAJ minus= σ

tdd curl curl AA σmicro minus=

AA) σωmicro iminus= curl )(curl(1

AA) σωmicro i=∆)((1

Eddy Current Tachometer

Construction of a speedometer (courtesy VDO Adolf Schinding AG) 1) spindle 2) bearing

3) holding spring 4) iron yoke 5) eddy current cup 6) shaft of the magnet 7) support of

the magnet 8) temperature compensation 9) permanent magnet 10) torsion spring

Proximity Sensors

Schematic diagram of a proximity sensor

Output current of a proximity switch versus distance

Inductive Flowmeters

)( Btimessdot= υqF

EqF sdot=BE times=υ

)(ds Btimes== υEU )(ds Btimes== υEU

)( Bd timessdot= υU

Bsdotsdotsdot= υdKU

Development of magnetic phase detection

sensor for steam generator tube

Dirac Son1 Kwan-Sang Ryu2 Duck-Gun Park3

1Hannam University Daejeon Rep of Korea2Korea Research Institute of Standards and Science Daejeon Rep of Korea3KoreaAtomic Energy Research Institute Daejeon Rep of Korea

Introduction

The layout of pressurized water reactor (PWR) components

Primary side Secondary side (non-radioactive side)(radioactive side)

The Structure of SG(Steam Generator)(degradation mechanism)

Secondary SidePrimary Side

SCC

A B

A-B

Steam outlet

Anti-vibration

SCC

Fretting

Wall thinning

IGA

U-bend

In commercial power plants SG- height up to 21 m - weight up to 800 tons - 2~4 sets of SG were installed - SG can contain from 3000 to

16000 tubes each about 20 mmin diameter

Primary coolant outlet Primary coolant inlet

Anti-vibrationbars

Tubesupportplate

Tubesheet

IGA

SCC

Pitting

SCC

Inside Tubesheet

Top of Tubesheet

by SSHwang of KAERI

Denting

Sludge pile

in diameter

The SGT is made of nickel basedInconel alloy which is composed of 75 Ni 165Cr and 815Fe

-Degradation mechanism corrosion pitting denting inter granular attack

-Inspection Eddy current Testing(ECT)

Permeability Variation Clusters (PVC)

(Ferro-magnetic phase)

-005

000

005

010

015

m (emug)

1-1

-002

000

002

004

006

008

m (emug)

1-2

-1000 -500 0 500 1000

-015

-010

-005

H ( Am )

-1000 -500 0 500 1000

-006

-004

-002

H ( Am )

The hystresis loop in the fragment of PVC parts of Kori-1 retired SG tube

-004

-002

000

002

004

006

M (emug)

Inconel 600 tested at RT

under tensile stress

1 2 3

4 5 6

7 8 9-004

-002

000

002

004

006

M(emug)

Inconel 600 Heat treated at

602 oC under tensile stress

1 2 3

How can we detect magnetic phase

(PVC)selectively from the flaws in SGT

-3000 -2000 -1000 0 1000 2000 3000

-006

H (Oe)

7 8 9

10 11 12

-3000 -2000 -1000 0 1000 2000 3000

-006

-004

H(Oe)

4 5 6

7 8 9

The hysteresis loop of the tensile tested specimen at room temperature (a) and tensile tested at high temperature (b)

The magnetic phase can be created under the high temperature andpressure conditions which is correspond to the stress corrosion crackingin the SG tube in the NPP(Bruemmer SM Charlot LA amp Henager CH (1988) Corrosion 782)

Principle of ECT

If we can separate magnetic phase selectively from the

flaws using magnetic sensor the reliability of EC in SGT

inspection will be greatly enhanced

Structure of the permeability

sensor

Dimension and photograph of U-shape

sensing yoke

Design of Magnetic Sensor for PVC

sensor sensing yoke

Photograph of the completed sensor front side (above) and rear side (bottom)

R11R12

R10

R8

R6

R9

R13

R7

R14

C18

1 n

C17

C20

C21

D2

DIODE

SIN COS

-

+

U-2A

4

13

2

-

+

U-2B

75

6

8

-

+

U-3A

13

2

8

+5VC19

104

+5V

Schematic diagram of the sensor system

Electronic Circuit of Magnetic Sensor

R20

R

R21

R

-

+

U5AD797

3

26

74

U6

D1

S12

GND3

+VCC4VCC5

IN6

-VCC7

S28

C41

R13

R26

R18

R25

R2210 Ω

R16

R14

R17

10 k

R15

R27

R32

R28

R33

R29

R34

5 k

R30

C29

C37

104

C32473

C39473C40

104

C33

104

C21

104C23

104

C25

104

C26

104

C30

104

C31

104

C35

104

C36

104

C27

104

C28

104

C34

104

C38

104

D3

DIODE

L1

1

2

L2

1

2

L3

1

2

4

-

+

U-4A

4

13

2

-

+

U-4B

75

6

8

-

+

U-5A

4

13

2

-

+

U-5B

75

6

8

-

+

U-6A

4

13

2

-

+

U-6B

75

6

8

C22

104

-5V

+5V

+5V

+5V

+5V

+5V

+5V

U7

D1

S12

GND3

+VCC4

VCC5

IN6

-VCC7

S28

+5V

-5V

-5V

-5V

-5V

-5V

-5V

-5V

-5V

R19

R24

R

R23

R

C24

OUT(X)

OUT(Y)

R1

20 kR210 k

R3

20 kR410 k

C1

104

C8

104

REF43

OUT(X)

OUT(Y)

REF43

U2

+Vcc1

CH02

CH13

CH24

CH35

COMM6

SHDN7

Vref8

+Vcc9

GND10

GND11

DOUT12BUSY13DIN14CS15

DIN16

-

+

U-1A

13

2

8

-

+

U-1B

4

75

6

C410 uF

C5104

DOUT

C210uF

C6104

C3104

DCLK

C7104

DIN

C10

01uF

CS

BUSY

C14 10uF

J1

CON6

123456

D1

DIODE

R5

47K

C9

10uF

C1310uF

Y1

OSC

OUT3

GND2

VCC4

U3

RSTVPP1

GND10

VCC20

XTAL15

XTAL24

P10AIN012P11AIN113P1214P1315P1416P1517P1618P1719

P30RXD2

P31TXD3

P32INT06

P33INT17

P34T08

P35T19

P3711

U4

C1+1

C1-3

C2+4

C2-5

VCC16

GND15

V+2

V-6

R1OUT12

R2OUT9

T1IN11

T2IN10

R1IN13

R2IN8

T1OUT14

T2OUT7

C12 10uF

C16

01uF

C15 10uF

C11

01uF

-5V

+5V

+5V

+5V

+5V

+5V

+5V

+5V

RST

OSC

OSC

RST

DCLKCSDINBUSYDOUT

U1

IN2

GND

4

OUT6

TEMP3

TRIM5

-5V

+5V

Electronic circuit diagram of the magnetic sensor

Photograph of the completed measuring system data acquisition

software in PC and probe scanning system

Experimental Setup for Magnetic Sensor

Reference material Scanning System Software LabVIEW

Reference Material (1) Normal defects and PVCs

Longitudinal and transverse defects

Def W L D Remarks

1 02 500 0213 (20 ) Inner defects

2 02 500 0427 (40 )

3 02 500 0213 (20 )Outer defectsPVC(1018)4 02 500 0427 (40 )

5 02 500 0639 (60 )

6 02 500 0852 (80 )

7 02 500 0639 (60 ) Inner defects

8 02 500 0852 (80 )

- 1 and 2 are inner defects

- 345 and 6 are outer defects with PVC

- 7 and 8 are inner defects

PVC

PVC

Defect Defect

For longitudinal defects and PVC For circumferential defects and PVC

ECT is very difficult to detect circumferential defects

We can distinguish PVCs and defects and longitudinal and circumferential defects

Flux-gate Magnetometer

One core sensor Two core sensor

3-축 flux-gate Magnetometer의 계략도

Sensorpia Co

pro

cess

or(

AV

R)

Sensor 1

RS422

Interface

Mic

ro-p

roce

ssor(

AV

R)

Sensor 2

Sensor 3

Interface

조립된 마그네토미터의 사진

Sensorpia Co

Analog PCB

Digital PCB

Sensorpia Co선형도(linearity)

10

20

30

40

50

60

y-axis

Magnetometer Output (microT)

-60 -50 -40 -30 -20 -10 0 10 20 30 40 50 60

-60

-50

-40

-30

-20

-10

0

10

Y-axis y=099946 x+0015STD 106E-4

Magnetometer Output (

Applied Magnetic Field (microT)

마그네토미터의 noise 특성 Sensorpia Co

1

10

100

y-axis

Magnetometer noise (nT)

0 1 2 3 4 5 6

1E-4

1E-3

001

01

Magnetometer noise (nT)

Frequency (Hz)

Magnetometer for KoDSAT

-150 -100 -50 0 50 100 150

-15

-10

-5

0

5

10

15

Magnetic Moment (Am

2)

Current (mA)

After Thermal Cycle Test

Measured

Resistance 193 ohm

Photograph of Magnetic torquer

Photograph of KoDSAT

Photograph of

3-axis Fluxgate

Magnetometer

Photograph of Magnetic torquer

Application of magnetometer

Moon magnetic fieldmeasurement

Telescope with direction indication

Joule Effect (Magnetostriction)

ϕ2cosel

l=

∆

0=∆

+∆

+∆

b

b

a

a

l

l

Actuator using Terfenol-D

00

05

10

B (T)

800

1000

1200

1400

1600

Magnetostriction (ppm)

-100 -50 0 50 100

-10

-05

00

B (T)

H (kAm)

2 MPa

4 MPa

6 MPa

8 MPa

10 MPa

12 MPa

-100 -50 0 50 100

-200

0

200

400

600

Magnetostriction (ppm)

H (kAm)

2 MPa

4 MPa

6 MPa

8 MPa

10 MPa

12 MPa

600

700

800

900

1000

-4 -3 -2 -1 0 1 2 3 4

0

10

20

30

40

50

60

Displacement (m

icro meter)

I (A)

FIELD

9 kAm

12 kAm

16 kAm

20 kAm

24 kAm

38 kAm

-50 -40 -30 -20 -10 0 10 20 30 40 50

-100

0

100

200

300

400

500

L (PPM)

H (kAm)

9 kAm

12 kAm

16 kAm

20 kAm

24 kAm

38 kAm

Magnetostrictive displacement sensor

Hysteresis loops under

tensile stress σ

(a) Crystalline 68 NiFe

λs = +25 10-6

(b) crystalline pure Ni λs

= -35 10-6

Villari Effect ( Inverse of Joule Effect)

= -35 10-6

(c) amorphous Co-based

alloy

λs = -35 10-6

ϕσλ 2sin2

3sdotsdot= smeE

γ

Permeability depending on the stress

σλmicromicro

1

3

2

Y

J

so

s

r =

γ

Calculated magnetization curves under stress

Variation of magnetization curve by an applied

tensile force (Co-based amorphous alloy)

Alloy Requirement

Materials for magnetoelastic sensors

Why amorphous magnetic materials are important

Stress-strain curves of several materials

Coercivity and hardness of several materials

Principles of magnetoelastic sensors

Non-contact torque sensor

Principle of cross torductor torque

sensor and flux pattern of sensor

poles on the surface of a shaft

a) without and b)with torsional load

Equivalent magnetic circuit of

cross type torque sensor

Helices of principal tensile and compressive stress on the surface of

a shaft subjected to torsion [32] Correlated changes of permeability

are detected by four-branch yoke system with sensing coils 123

and 4 and a common excitation pole

Examples of torque sensors

Four-branch type torque sensor

heads Pole structures realized

by commercial multi-pole

ferrites 14 and 18 min in

diameter (diameter of sensor

h e a d 1 7 a n d 2 4 m m

respectively) respectively)

Principle of Ring Torductor torque transducer

(a b) Physical structure (c) evolution of the

shaft surface under the transducer poles A and BRing torductor for measuring

torque on ship propeller shafts

(shaft diameter ca 500 mm)

(Courtesy ASEA Brown

Boveri AG)

Principal designs of coaxial torque sensors

Schematic diagram of data processing

electronics of a torque sensor

Extensometer (a) Construction of strain sensing element using

amorphous ribbon wound core (b) configuration of lumped

windings

∆E effect of an amorphous FeNi-based

alloy (Fe40 Ni38 Mo4 B18) Hs saturation

field

Magnetically tunable delay line

Torque Sensors using Amorphous wire

Sixtus tonk효과(large Barkhausen효과)

Hysteresis loops of a Wiegand wire for different reset fields

Curie 온도 및Hopkinson효과

Relation between normalised

saturation polarisation and

normalised Curie temperature

Permeability of a Mn-Zn ferrite as

a function of temperature and field

strength

Conclusions

1) Magnetic sensor 는 자동차 공장자동화 항공우주 및 군사용으로많이 사용되고 있다

2) 새로운 소재개발은 자기센서의 성능개발에 직접적인 영향을 준다2) 새로운 소재개발은 자기센서의 성능개발에 직접적인 영향을 준다

3) 센서의 개발을 위해서는 다양한 전공지식이 요구된다

(물리학 재료공학 기계공학 전자공학)

4) 센서분야가 고부가가치를 창출하는 부품사업이다

5) 핵심부품을 생산하는 중소기업의 item으로도 적절하다

Sensor with transformer coupled negative feedback to the coil

)(i)()(F

0 ωωωω FR

UMUAU A

A sdot

minus=

)( i1

)(

F

0

ωω

ω

FR

MA

FAUU A

sdot+

sdot=

Induction coil connected to a voltage amplifier with

transformer coupled negative feedback to the coil

FR

21

1K0

i1

1

i1

i )(

ωωωωωω

ωω

+sdot

+sdot=

M

RUU A

IIF2 CRL

MAf

sdotsdotsdotsdot

=∆π

Frequency response of the output voltage UA of an induction coil sensor with negative feedback transformer coupled to the coil

Applications of search coil magnetometer

Developed search coil magnetometer using amorphous ribbon

Experimental setup for the effective permeability measurement

Relative permeability depending on the numbers of ribbon(a)

and the air gap between ribbons

Relative permeability depending on the number of ribbons for the different air gap between ribbons

Relative permeability depending on the total number of ribbons for the different air gap between ribbons

10 pT

100 pT

1 pT

Noise spectrum of the developed search coil magnetometer

BJne

E xH

1minus=

neRH

1minus=

22 nP micromicro minus

Hall 효과

Bt

IRU H

HL =

2

22

)( he

eh

Hpne

nPR

micromicromicromicro

+

minus=

Rectangular Hall plate (cc1cc2 current constant sc1sc2

sensor constant I bias current U voltage drop UH Hall

voltage

Physics carrier concentration and kind of carrier measurement

Engineering magnetic field measurement

Current Measurement

Arrangement for noninvasive

current measurement using an iron

core The current to be measured

produces a proportional magnetic

field which can be measured in the

air gap

Characteristic curve produced by

the current

Arrangement for indirect noninvasive

current measurement using the

compensation principle An iron core as

represented in Figure 3-29 is held field

free by injection a current into a

compensating coil wound on the core

which offsets the field generated by the

current being measured The Hall effect

sensor in the air gap serves as a null

indicator

Circuit diagram for AC-power

measurement using a Hall effect

sensor

DC Power Measurement

Circuit diagram for DC-

power measurement using a

Hall effect sensor

Noncontact Position Sensing

Galvanomagnetic components for sensing the position of permanent magnets

and magnetically conductive materials

Current Sensor Based on Hall Sensor

and Magnetic Core for Hybrid Vehicle

KH Yeon1 SD Kim1 and D Son2 1Auto industry co14F Hanshin IT tower Guro Gu Seoul Korea2Hannam UniversityOjung dong 133 Daejeon Rep of Korea

i

Hall sensor

B

I

SB

ring core

B

I10

g

N

Bl S

micro

)( gtgtrmicro

gab core

Current Sensor Based on Hall

Sensor and Magnetic Core

Hall

Effect

Device

CurrentVoltage

applying for

Hall effect device

operation

Output

signals

Magnetic field

Occurred by

current measurement

Signal

process

circuits

Developed Current Sensor

Magnetic core

Hall sensor

PCB

25

30

35

40

45

50

Output voltage V

Current sensor(Open loop type)

Temp 25C

400A model

+400 ~ -400A

SD 000128

Linearity 003

Linearity of the sensor

Characteristics of the Current Sensors

1000A 10 V power supply

-500 -400 -300 -200 -100 0 100 200 300 400 500

00

05

10

15

20

Output voltage V

current A

Temperature 25Linearity 003

Measuring range -400A ~ +400A

1000A Electronic Load

-3

0

3

6

9

12

15

18

dB

Current sensor

DV2 PCB 24pF

40Aturns

Frequency bandwidth

Gain bandwidth 3 MHz

Current 10 A

Temperature 25

Frequency bandwidth 100 kHz

Sensor output voltage vs frequency

at applied current of 40 Aturns

1 10 100

-18

-15

-12

-9

-6

Frequency kHz 측정온도 25

주파수특성 30kHz 이상(3dB 기준)

측정전류 40Aturns(4A 10턴)

측정주파수 100Hz ~ 100kHz

Temperature 25Current 40Aturns

Frequency range 100 Hz ~ 100 kHz

What is Magnetoresistance

Magnetoresistance effect(AMR)

θθθ 2cos2

12sin12cos(

22 minusminus+∆asymp∆ xxxmx hhhRR

32 minusasymp∆ ρρ New effect GMR CMR and GMI

10 ge∆ ρρ

Two bridge configuration for

rotational angle measurement

measurement angle more than 180o

자동차 Engine Management System

Inductive and Eddy Current

Sensors Excited by Permanent Magnets

tNtU dd)( φsdotminus=

construction of an inductive

sensor (courtesy VDO Adolf sensor (courtesy VDO Adolf

Schindling AG)

1) constant socket

2) terminal package

3) permanent magnet

4) cap

5) soft magnetic core

6) coil

7) plate

8) blade connector

γγ

Sensor with yoke Change in the magnetic flux with

varying air gap Continuous lines

minimum air gap dashed lines

maximum air gap

C-shaped sensor

Sensor with radially

magnetized

permanent magnet

Signal Conditioning

Output voltage U of a DC-excited sensor with permanent

magnets when a single iron object passes by

Schematic electrical diagram of an inductive sensor

Linear Variable Differential Transformer

AC-Excited Sensors for Linear Movement

Principle of construction of an LVDT

Electrical circuit of an LVDT

tIMtNU dd dd sdotminus=sdotminus= φ

tIMtIMUUU dd dd 1212 sdotminussdot=minus=

tIMMU dd)( 12 sdotminus=

)(12 xMMMM =minus=

tIxMU dd)( sdot= tI

UxM

dd)( =

Signal Conditioning

power supply

carrier gen

autoampcontrol

LVDTcarrieramp

demod-ulator

phase

shifter

power supply

carrier gen

passivedemod-ulator

LVDTDCamp

Block diagram of a carrier amplifier system

Block diagram of a DC amplifier system

Variable Inductive Sensors

Principle of construction

of the VLP sensor

Principle of a bridge

circuit

lANL r 20 sdotsdotsdot= micromicro

21 BA UUU minus=

21)i(ii( 211 minus+sdot= LLLUU BA ωωω

)21))()((( minus∆minus+∆+∆+sdot= LLLLLLUU BA

)212)(( minus∆+sdot= LLLUU )212)(( minus∆+sdot= LLLUU BA

LLUU BA 21 ∆sdotsdot=

llLL ∆sdot=∆ d d

llLLUU BA ∆sdotsdot= d d)2(1

Applications and Properties

Principle of a construction of a force transducer

(courtesy Hottinger Baldwin Messtechnik)

Vibrationacceleration sensor

Signal Conditioning

Schematic electrical diagram of a force transducer connected with an

amplifier (courtesy Hottinger Baldwin Messtechnik GmbH)

Variable Gap Sensors

)( FeFe2

0 LLllANL micromicromicro +sdotsdot=

FeFe2

0max lANL sdotsdotsdot= micromicro

Construction of a variable gap sensor

Characteristic of a variable gap sensor

Construction of a differential

cross-anchor sensor

Output voltage U versus core

position x plusmn a limits of the

linear rage

Applications of differential cross-anchor sensors

AC-excited Sensors for Rotary Movements

Principle of construction of a synchro

α cos10 sdotsdot= UKU y

)120-( cos10 degsdotsdot= αUKU z

)240-( cos10 degsdotsdot= αUKU x

)120-( sin3100 degsdotsdotsdot=minus= αKUUUU yxyx

)240-( sin3100 degsdotsdotsdot=minus= αKUUUU zyzy

α sin3100 sdotsdotsdot=minus= KUUUU xzxz

Application to the Torque Sensor

Principle of construction of a torque-type synchro

Torque versus angular

difference

)( sin~ rt αα minussdotKM

)( cos~ rt1r αα minussdotUU

Principle of construction of a control-type sensor

Output voltage versus

angular difference

Principle of construction of a differential sychro

Eddy Current Sensors

tBE dd curl minus=JH = curl

0 div =BH(H)B sdot= micro

E(E)J sdot= σ

A B curl= A B curl=

tdd- A E =

)dd( tAJ minus= σ

tdd curl curl AA σmicro minus=

AA) σωmicro iminus= curl )(curl(1

AA) σωmicro i=∆)((1

Eddy Current Tachometer

Construction of a speedometer (courtesy VDO Adolf Schinding AG) 1) spindle 2) bearing

3) holding spring 4) iron yoke 5) eddy current cup 6) shaft of the magnet 7) support of

the magnet 8) temperature compensation 9) permanent magnet 10) torsion spring

Proximity Sensors

Schematic diagram of a proximity sensor

Output current of a proximity switch versus distance

Inductive Flowmeters

)( Btimessdot= υqF

EqF sdot=BE times=υ

)(ds Btimes== υEU )(ds Btimes== υEU

)( Bd timessdot= υU

Bsdotsdotsdot= υdKU

Development of magnetic phase detection

sensor for steam generator tube

Dirac Son1 Kwan-Sang Ryu2 Duck-Gun Park3

1Hannam University Daejeon Rep of Korea2Korea Research Institute of Standards and Science Daejeon Rep of Korea3KoreaAtomic Energy Research Institute Daejeon Rep of Korea

Introduction

The layout of pressurized water reactor (PWR) components

Primary side Secondary side (non-radioactive side)(radioactive side)

The Structure of SG(Steam Generator)(degradation mechanism)

Secondary SidePrimary Side

SCC

A B

A-B

Steam outlet

Anti-vibration

SCC

Fretting

Wall thinning

IGA

U-bend

In commercial power plants SG- height up to 21 m - weight up to 800 tons - 2~4 sets of SG were installed - SG can contain from 3000 to

16000 tubes each about 20 mmin diameter

Primary coolant outlet Primary coolant inlet

Anti-vibrationbars

Tubesupportplate

Tubesheet

IGA

SCC

Pitting

SCC

Inside Tubesheet

Top of Tubesheet

by SSHwang of KAERI

Denting

Sludge pile

in diameter

The SGT is made of nickel basedInconel alloy which is composed of 75 Ni 165Cr and 815Fe

-Degradation mechanism corrosion pitting denting inter granular attack

-Inspection Eddy current Testing(ECT)

Permeability Variation Clusters (PVC)

(Ferro-magnetic phase)

-005

000

005

010

015

m (emug)

1-1

-002

000

002

004

006

008

m (emug)

1-2

-1000 -500 0 500 1000

-015

-010

-005

H ( Am )

-1000 -500 0 500 1000

-006

-004

-002

H ( Am )

The hystresis loop in the fragment of PVC parts of Kori-1 retired SG tube

-004

-002

000

002

004

006

M (emug)

Inconel 600 tested at RT

under tensile stress

1 2 3

4 5 6

7 8 9-004

-002

000

002

004

006

M(emug)

Inconel 600 Heat treated at

602 oC under tensile stress

1 2 3

How can we detect magnetic phase

(PVC)selectively from the flaws in SGT

-3000 -2000 -1000 0 1000 2000 3000

-006

H (Oe)

7 8 9

10 11 12

-3000 -2000 -1000 0 1000 2000 3000

-006

-004

H(Oe)

4 5 6

7 8 9

The hysteresis loop of the tensile tested specimen at room temperature (a) and tensile tested at high temperature (b)

The magnetic phase can be created under the high temperature andpressure conditions which is correspond to the stress corrosion crackingin the SG tube in the NPP(Bruemmer SM Charlot LA amp Henager CH (1988) Corrosion 782)

Principle of ECT

If we can separate magnetic phase selectively from the

flaws using magnetic sensor the reliability of EC in SGT

inspection will be greatly enhanced

Structure of the permeability

sensor

Dimension and photograph of U-shape

sensing yoke

Design of Magnetic Sensor for PVC

sensor sensing yoke

Photograph of the completed sensor front side (above) and rear side (bottom)

R11R12

R10

R8

R6

R9

R13

R7

R14

C18

1 n

C17

C20

C21

D2

DIODE

SIN COS

-

+

U-2A

4

13

2

-

+

U-2B

75

6

8

-

+

U-3A

13

2

8

+5VC19

104

+5V

Schematic diagram of the sensor system

Electronic Circuit of Magnetic Sensor

R20

R

R21

R

-

+

U5AD797

3

26

74

U6

D1

S12

GND3

+VCC4VCC5

IN6

-VCC7

S28

C41

R13

R26

R18

R25

R2210 Ω

R16

R14

R17

10 k

R15

R27

R32

R28

R33

R29

R34

5 k

R30

C29

C37

104

C32473

C39473C40

104

C33

104

C21

104C23

104

C25

104

C26

104

C30

104

C31

104

C35

104

C36

104

C27

104

C28

104

C34

104

C38

104

D3

DIODE

L1

1

2

L2

1

2

L3

1

2

4

-

+

U-4A

4

13

2

-

+

U-4B

75

6

8

-

+

U-5A

4

13

2

-

+

U-5B

75

6

8

-

+

U-6A

4

13

2

-

+

U-6B

75

6

8

C22

104

-5V

+5V

+5V

+5V

+5V

+5V

+5V

U7

D1

S12

GND3

+VCC4

VCC5

IN6

-VCC7

S28

+5V

-5V

-5V

-5V

-5V

-5V

-5V

-5V

-5V

R19

R24

R

R23

R

C24

OUT(X)

OUT(Y)

R1

20 kR210 k

R3

20 kR410 k

C1

104

C8

104

REF43

OUT(X)

OUT(Y)

REF43

U2

+Vcc1

CH02

CH13

CH24

CH35

COMM6

SHDN7

Vref8

+Vcc9

GND10

GND11

DOUT12BUSY13DIN14CS15

DIN16

-

+

U-1A

13

2

8

-

+

U-1B

4

75

6

C410 uF

C5104

DOUT

C210uF

C6104

C3104

DCLK

C7104

DIN

C10

01uF

CS

BUSY

C14 10uF

J1

CON6

123456

D1

DIODE

R5

47K

C9

10uF

C1310uF

Y1

OSC

OUT3

GND2

VCC4

U3

RSTVPP1

GND10

VCC20

XTAL15

XTAL24

P10AIN012P11AIN113P1214P1315P1416P1517P1618P1719

P30RXD2

P31TXD3

P32INT06

P33INT17

P34T08

P35T19

P3711

U4

C1+1

C1-3

C2+4

C2-5

VCC16

GND15

V+2

V-6

R1OUT12

R2OUT9

T1IN11

T2IN10

R1IN13

R2IN8

T1OUT14

T2OUT7

C12 10uF

C16

01uF

C15 10uF

C11

01uF

-5V

+5V

+5V

+5V

+5V

+5V

+5V

+5V

RST

OSC

OSC

RST

DCLKCSDINBUSYDOUT

U1

IN2

GND

4

OUT6

TEMP3

TRIM5

-5V

+5V

Electronic circuit diagram of the magnetic sensor

Photograph of the completed measuring system data acquisition

software in PC and probe scanning system

Experimental Setup for Magnetic Sensor

Reference material Scanning System Software LabVIEW

Reference Material (1) Normal defects and PVCs

Longitudinal and transverse defects

Def W L D Remarks

1 02 500 0213 (20 ) Inner defects

2 02 500 0427 (40 )

3 02 500 0213 (20 )Outer defectsPVC(1018)4 02 500 0427 (40 )

5 02 500 0639 (60 )

6 02 500 0852 (80 )

7 02 500 0639 (60 ) Inner defects

8 02 500 0852 (80 )

- 1 and 2 are inner defects

- 345 and 6 are outer defects with PVC

- 7 and 8 are inner defects

PVC

PVC

Defect Defect

For longitudinal defects and PVC For circumferential defects and PVC

ECT is very difficult to detect circumferential defects

We can distinguish PVCs and defects and longitudinal and circumferential defects

Flux-gate Magnetometer

One core sensor Two core sensor

3-축 flux-gate Magnetometer의 계략도

Sensorpia Co

pro

cess

or(

AV

R)

Sensor 1

RS422

Interface

Mic

ro-p

roce

ssor(

AV

R)

Sensor 2

Sensor 3

Interface

조립된 마그네토미터의 사진

Sensorpia Co

Analog PCB

Digital PCB

Sensorpia Co선형도(linearity)

10

20

30

40

50

60

y-axis

Magnetometer Output (microT)

-60 -50 -40 -30 -20 -10 0 10 20 30 40 50 60

-60

-50

-40

-30

-20

-10

0

10

Y-axis y=099946 x+0015STD 106E-4

Magnetometer Output (

Applied Magnetic Field (microT)

마그네토미터의 noise 특성 Sensorpia Co

1

10

100

y-axis

Magnetometer noise (nT)

0 1 2 3 4 5 6

1E-4

1E-3

001

01

Magnetometer noise (nT)

Frequency (Hz)

Magnetometer for KoDSAT

-150 -100 -50 0 50 100 150

-15

-10

-5

0

5

10

15

Magnetic Moment (Am

2)

Current (mA)

After Thermal Cycle Test

Measured

Resistance 193 ohm

Photograph of Magnetic torquer

Photograph of KoDSAT

Photograph of

3-axis Fluxgate

Magnetometer

Photograph of Magnetic torquer

Application of magnetometer

Moon magnetic fieldmeasurement

Telescope with direction indication

Joule Effect (Magnetostriction)

ϕ2cosel

l=

∆

0=∆

+∆

+∆

b

b

a

a

l

l

Actuator using Terfenol-D

00

05

10

B (T)

800

1000

1200

1400

1600

Magnetostriction (ppm)

-100 -50 0 50 100

-10

-05

00

B (T)

H (kAm)

2 MPa

4 MPa

6 MPa

8 MPa

10 MPa

12 MPa

-100 -50 0 50 100

-200

0

200

400

600

Magnetostriction (ppm)

H (kAm)

2 MPa

4 MPa

6 MPa

8 MPa

10 MPa

12 MPa

600

700

800

900

1000

-4 -3 -2 -1 0 1 2 3 4

0

10

20

30

40

50

60

Displacement (m

icro meter)

I (A)

FIELD

9 kAm

12 kAm

16 kAm

20 kAm

24 kAm

38 kAm

-50 -40 -30 -20 -10 0 10 20 30 40 50

-100

0

100

200

300

400

500

L (PPM)

H (kAm)

9 kAm

12 kAm

16 kAm

20 kAm

24 kAm

38 kAm

Magnetostrictive displacement sensor

Hysteresis loops under

tensile stress σ

(a) Crystalline 68 NiFe

λs = +25 10-6

(b) crystalline pure Ni λs

= -35 10-6

Villari Effect ( Inverse of Joule Effect)

= -35 10-6

(c) amorphous Co-based

alloy

λs = -35 10-6

ϕσλ 2sin2

3sdotsdot= smeE

γ

Permeability depending on the stress

σλmicromicro

1

3

2

Y

J

so

s

r =

γ

Calculated magnetization curves under stress

Variation of magnetization curve by an applied

tensile force (Co-based amorphous alloy)

Alloy Requirement

Materials for magnetoelastic sensors

Why amorphous magnetic materials are important

Stress-strain curves of several materials

Coercivity and hardness of several materials

Principles of magnetoelastic sensors

Non-contact torque sensor

Principle of cross torductor torque

sensor and flux pattern of sensor

poles on the surface of a shaft

a) without and b)with torsional load

Equivalent magnetic circuit of

cross type torque sensor

Helices of principal tensile and compressive stress on the surface of

a shaft subjected to torsion [32] Correlated changes of permeability

are detected by four-branch yoke system with sensing coils 123

and 4 and a common excitation pole

Examples of torque sensors

Four-branch type torque sensor

heads Pole structures realized

by commercial multi-pole

ferrites 14 and 18 min in

diameter (diameter of sensor

h e a d 1 7 a n d 2 4 m m

respectively) respectively)

Principle of Ring Torductor torque transducer

(a b) Physical structure (c) evolution of the

shaft surface under the transducer poles A and BRing torductor for measuring

torque on ship propeller shafts

(shaft diameter ca 500 mm)

(Courtesy ASEA Brown

Boveri AG)

Principal designs of coaxial torque sensors

Schematic diagram of data processing

electronics of a torque sensor

Extensometer (a) Construction of strain sensing element using

amorphous ribbon wound core (b) configuration of lumped

windings

∆E effect of an amorphous FeNi-based

alloy (Fe40 Ni38 Mo4 B18) Hs saturation

field

Magnetically tunable delay line

Torque Sensors using Amorphous wire

Sixtus tonk효과(large Barkhausen효과)

Hysteresis loops of a Wiegand wire for different reset fields

Curie 온도 및Hopkinson효과

Relation between normalised

saturation polarisation and

normalised Curie temperature

Permeability of a Mn-Zn ferrite as

a function of temperature and field

strength

Conclusions

1) Magnetic sensor 는 자동차 공장자동화 항공우주 및 군사용으로많이 사용되고 있다

2) 새로운 소재개발은 자기센서의 성능개발에 직접적인 영향을 준다2) 새로운 소재개발은 자기센서의 성능개발에 직접적인 영향을 준다

3) 센서의 개발을 위해서는 다양한 전공지식이 요구된다

(물리학 재료공학 기계공학 전자공학)

4) 센서분야가 고부가가치를 창출하는 부품사업이다

5) 핵심부품을 생산하는 중소기업의 item으로도 적절하다

Frequency response of the output voltage UA of an induction coil sensor with negative feedback transformer coupled to the coil

Applications of search coil magnetometer

Developed search coil magnetometer using amorphous ribbon

Experimental setup for the effective permeability measurement

Relative permeability depending on the numbers of ribbon(a)

and the air gap between ribbons

Relative permeability depending on the number of ribbons for the different air gap between ribbons

Relative permeability depending on the total number of ribbons for the different air gap between ribbons

10 pT

100 pT

1 pT

Noise spectrum of the developed search coil magnetometer

BJne

E xH

1minus=

neRH

1minus=

22 nP micromicro minus

Hall 효과

Bt

IRU H

HL =

2

22

)( he

eh

Hpne

nPR

micromicromicromicro

+

minus=

Rectangular Hall plate (cc1cc2 current constant sc1sc2

sensor constant I bias current U voltage drop UH Hall

voltage

Physics carrier concentration and kind of carrier measurement

Engineering magnetic field measurement

Current Measurement

Arrangement for noninvasive

current measurement using an iron

core The current to be measured

produces a proportional magnetic

field which can be measured in the

air gap

Characteristic curve produced by

the current

Arrangement for indirect noninvasive

current measurement using the

compensation principle An iron core as

represented in Figure 3-29 is held field

free by injection a current into a

compensating coil wound on the core

which offsets the field generated by the

current being measured The Hall effect

sensor in the air gap serves as a null

indicator

Circuit diagram for AC-power

measurement using a Hall effect

sensor

DC Power Measurement

Circuit diagram for DC-

power measurement using a

Hall effect sensor

Noncontact Position Sensing

Galvanomagnetic components for sensing the position of permanent magnets

and magnetically conductive materials

Current Sensor Based on Hall Sensor

and Magnetic Core for Hybrid Vehicle

KH Yeon1 SD Kim1 and D Son2 1Auto industry co14F Hanshin IT tower Guro Gu Seoul Korea2Hannam UniversityOjung dong 133 Daejeon Rep of Korea

i

Hall sensor

B

I

SB

ring core

B

I10

g

N

Bl S

micro

)( gtgtrmicro

gab core

Current Sensor Based on Hall

Sensor and Magnetic Core

Hall

Effect

Device

CurrentVoltage

applying for

Hall effect device

operation

Output

signals

Magnetic field

Occurred by

current measurement

Signal

process

circuits

Developed Current Sensor

Magnetic core

Hall sensor

PCB

25

30

35

40

45

50

Output voltage V

Current sensor(Open loop type)

Temp 25C

400A model

+400 ~ -400A

SD 000128

Linearity 003

Linearity of the sensor

Characteristics of the Current Sensors

1000A 10 V power supply

-500 -400 -300 -200 -100 0 100 200 300 400 500

00

05

10

15

20

Output voltage V

current A

Temperature 25Linearity 003

Measuring range -400A ~ +400A

1000A Electronic Load

-3

0

3

6

9

12

15

18

dB

Current sensor

DV2 PCB 24pF

40Aturns

Frequency bandwidth

Gain bandwidth 3 MHz

Current 10 A

Temperature 25

Frequency bandwidth 100 kHz

Sensor output voltage vs frequency

at applied current of 40 Aturns

1 10 100

-18

-15

-12

-9

-6

Frequency kHz 측정온도 25

주파수특성 30kHz 이상(3dB 기준)

측정전류 40Aturns(4A 10턴)

측정주파수 100Hz ~ 100kHz

Temperature 25Current 40Aturns

Frequency range 100 Hz ~ 100 kHz

What is Magnetoresistance

Magnetoresistance effect(AMR)

θθθ 2cos2

12sin12cos(

22 minusminus+∆asymp∆ xxxmx hhhRR

32 minusasymp∆ ρρ New effect GMR CMR and GMI

10 ge∆ ρρ

Two bridge configuration for

rotational angle measurement

measurement angle more than 180o

자동차 Engine Management System

Inductive and Eddy Current

Sensors Excited by Permanent Magnets

tNtU dd)( φsdotminus=

construction of an inductive

sensor (courtesy VDO Adolf sensor (courtesy VDO Adolf

Schindling AG)

1) constant socket

2) terminal package

3) permanent magnet

4) cap

5) soft magnetic core

6) coil

7) plate

8) blade connector

γγ

Sensor with yoke Change in the magnetic flux with

varying air gap Continuous lines

minimum air gap dashed lines

maximum air gap

C-shaped sensor

Sensor with radially

magnetized

permanent magnet

Signal Conditioning

Output voltage U of a DC-excited sensor with permanent

magnets when a single iron object passes by

Schematic electrical diagram of an inductive sensor

Linear Variable Differential Transformer

AC-Excited Sensors for Linear Movement

Principle of construction of an LVDT

Electrical circuit of an LVDT

tIMtNU dd dd sdotminus=sdotminus= φ

tIMtIMUUU dd dd 1212 sdotminussdot=minus=

tIMMU dd)( 12 sdotminus=

)(12 xMMMM =minus=

tIxMU dd)( sdot= tI

UxM

dd)( =

Signal Conditioning

power supply

carrier gen

autoampcontrol

LVDTcarrieramp

demod-ulator

phase

shifter

power supply

carrier gen

passivedemod-ulator

LVDTDCamp

Block diagram of a carrier amplifier system

Block diagram of a DC amplifier system

Variable Inductive Sensors

Principle of construction

of the VLP sensor

Principle of a bridge

circuit

lANL r 20 sdotsdotsdot= micromicro

21 BA UUU minus=

21)i(ii( 211 minus+sdot= LLLUU BA ωωω

)21))()((( minus∆minus+∆+∆+sdot= LLLLLLUU BA

)212)(( minus∆+sdot= LLLUU )212)(( minus∆+sdot= LLLUU BA

LLUU BA 21 ∆sdotsdot=

llLL ∆sdot=∆ d d

llLLUU BA ∆sdotsdot= d d)2(1

Applications and Properties

Principle of a construction of a force transducer

(courtesy Hottinger Baldwin Messtechnik)

Vibrationacceleration sensor

Signal Conditioning

Schematic electrical diagram of a force transducer connected with an

amplifier (courtesy Hottinger Baldwin Messtechnik GmbH)

Variable Gap Sensors

)( FeFe2

0 LLllANL micromicromicro +sdotsdot=

FeFe2

0max lANL sdotsdotsdot= micromicro

Construction of a variable gap sensor

Characteristic of a variable gap sensor

Construction of a differential

cross-anchor sensor

Output voltage U versus core

position x plusmn a limits of the

linear rage

Applications of differential cross-anchor sensors

AC-excited Sensors for Rotary Movements

Principle of construction of a synchro

α cos10 sdotsdot= UKU y

)120-( cos10 degsdotsdot= αUKU z

)240-( cos10 degsdotsdot= αUKU x

)120-( sin3100 degsdotsdotsdot=minus= αKUUUU yxyx

)240-( sin3100 degsdotsdotsdot=minus= αKUUUU zyzy

α sin3100 sdotsdotsdot=minus= KUUUU xzxz

Application to the Torque Sensor

Principle of construction of a torque-type synchro

Torque versus angular

difference

)( sin~ rt αα minussdotKM

)( cos~ rt1r αα minussdotUU

Principle of construction of a control-type sensor

Output voltage versus

angular difference

Principle of construction of a differential sychro

Eddy Current Sensors

tBE dd curl minus=JH = curl

0 div =BH(H)B sdot= micro

E(E)J sdot= σ

A B curl= A B curl=

tdd- A E =

)dd( tAJ minus= σ

tdd curl curl AA σmicro minus=

AA) σωmicro iminus= curl )(curl(1

AA) σωmicro i=∆)((1

Eddy Current Tachometer

Construction of a speedometer (courtesy VDO Adolf Schinding AG) 1) spindle 2) bearing

3) holding spring 4) iron yoke 5) eddy current cup 6) shaft of the magnet 7) support of

the magnet 8) temperature compensation 9) permanent magnet 10) torsion spring

Proximity Sensors

Schematic diagram of a proximity sensor

Output current of a proximity switch versus distance

Inductive Flowmeters

)( Btimessdot= υqF

EqF sdot=BE times=υ

)(ds Btimes== υEU )(ds Btimes== υEU

)( Bd timessdot= υU

Bsdotsdotsdot= υdKU

Development of magnetic phase detection

sensor for steam generator tube

Dirac Son1 Kwan-Sang Ryu2 Duck-Gun Park3

1Hannam University Daejeon Rep of Korea2Korea Research Institute of Standards and Science Daejeon Rep of Korea3KoreaAtomic Energy Research Institute Daejeon Rep of Korea

Introduction

The layout of pressurized water reactor (PWR) components

Primary side Secondary side (non-radioactive side)(radioactive side)

The Structure of SG(Steam Generator)(degradation mechanism)

Secondary SidePrimary Side

SCC

A B

A-B

Steam outlet

Anti-vibration

SCC

Fretting

Wall thinning

IGA

U-bend

In commercial power plants SG- height up to 21 m - weight up to 800 tons - 2~4 sets of SG were installed - SG can contain from 3000 to

16000 tubes each about 20 mmin diameter

Primary coolant outlet Primary coolant inlet

Anti-vibrationbars

Tubesupportplate

Tubesheet

IGA

SCC

Pitting

SCC

Inside Tubesheet

Top of Tubesheet

by SSHwang of KAERI

Denting

Sludge pile

in diameter

The SGT is made of nickel basedInconel alloy which is composed of 75 Ni 165Cr and 815Fe

-Degradation mechanism corrosion pitting denting inter granular attack

-Inspection Eddy current Testing(ECT)

Permeability Variation Clusters (PVC)

(Ferro-magnetic phase)

-005

000

005

010

015

m (emug)

1-1

-002

000

002

004

006

008

m (emug)

1-2

-1000 -500 0 500 1000

-015

-010

-005

H ( Am )

-1000 -500 0 500 1000

-006

-004

-002

H ( Am )

The hystresis loop in the fragment of PVC parts of Kori-1 retired SG tube

-004

-002

000

002

004

006

M (emug)

Inconel 600 tested at RT

under tensile stress

1 2 3

4 5 6

7 8 9-004

-002

000

002

004

006

M(emug)

Inconel 600 Heat treated at

602 oC under tensile stress

1 2 3

How can we detect magnetic phase

(PVC)selectively from the flaws in SGT

-3000 -2000 -1000 0 1000 2000 3000

-006

H (Oe)

7 8 9

10 11 12

-3000 -2000 -1000 0 1000 2000 3000

-006

-004

H(Oe)

4 5 6

7 8 9

The hysteresis loop of the tensile tested specimen at room temperature (a) and tensile tested at high temperature (b)

The magnetic phase can be created under the high temperature andpressure conditions which is correspond to the stress corrosion crackingin the SG tube in the NPP(Bruemmer SM Charlot LA amp Henager CH (1988) Corrosion 782)

Principle of ECT

If we can separate magnetic phase selectively from the

flaws using magnetic sensor the reliability of EC in SGT

inspection will be greatly enhanced

Structure of the permeability

sensor

Dimension and photograph of U-shape

sensing yoke

Design of Magnetic Sensor for PVC

sensor sensing yoke

Photograph of the completed sensor front side (above) and rear side (bottom)

R11R12

R10

R8

R6

R9

R13

R7

R14

C18

1 n

C17

C20

C21

D2

DIODE

SIN COS

-

+

U-2A

4

13

2

-

+

U-2B

75

6

8

-

+

U-3A

13

2

8

+5VC19

104

+5V

Schematic diagram of the sensor system

Electronic Circuit of Magnetic Sensor

R20

R

R21

R

-

+

U5AD797

3

26

74

U6

D1

S12

GND3

+VCC4VCC5

IN6

-VCC7

S28

C41

R13

R26

R18

R25

R2210 Ω

R16

R14

R17

10 k

R15

R27

R32

R28

R33

R29

R34

5 k

R30

C29

C37

104

C32473

C39473C40

104

C33

104

C21

104C23

104

C25

104

C26

104

C30

104

C31

104

C35

104

C36

104

C27

104

C28

104

C34

104

C38

104

D3

DIODE

L1

1

2

L2

1

2

L3

1

2

4

-

+

U-4A

4

13

2

-

+

U-4B

75

6

8

-

+

U-5A

4

13

2

-

+

U-5B

75

6

8

-

+

U-6A

4

13

2

-

+

U-6B

75

6

8

C22

104

-5V

+5V

+5V

+5V

+5V

+5V

+5V

U7

D1

S12

GND3

+VCC4

VCC5

IN6

-VCC7

S28

+5V

-5V

-5V

-5V

-5V

-5V

-5V

-5V

-5V

R19

R24

R

R23

R

C24

OUT(X)

OUT(Y)

R1

20 kR210 k

R3

20 kR410 k

C1

104

C8

104

REF43

OUT(X)

OUT(Y)

REF43

U2

+Vcc1

CH02

CH13

CH24

CH35

COMM6

SHDN7

Vref8

+Vcc9

GND10

GND11

DOUT12BUSY13DIN14CS15

DIN16

-

+

U-1A

13

2

8

-

+

U-1B

4

75

6

C410 uF

C5104

DOUT

C210uF

C6104

C3104

DCLK

C7104

DIN

C10

01uF

CS

BUSY

C14 10uF

J1

CON6

123456

D1

DIODE

R5

47K

C9

10uF

C1310uF

Y1

OSC

OUT3

GND2

VCC4

U3

RSTVPP1

GND10

VCC20

XTAL15

XTAL24

P10AIN012P11AIN113P1214P1315P1416P1517P1618P1719

P30RXD2

P31TXD3

P32INT06

P33INT17

P34T08

P35T19

P3711

U4

C1+1

C1-3

C2+4

C2-5

VCC16

GND15

V+2

V-6

R1OUT12

R2OUT9

T1IN11

T2IN10

R1IN13

R2IN8

T1OUT14

T2OUT7

C12 10uF

C16

01uF

C15 10uF

C11

01uF

-5V

+5V

+5V

+5V

+5V

+5V

+5V

+5V

RST

OSC

OSC

RST

DCLKCSDINBUSYDOUT

U1

IN2

GND

4

OUT6

TEMP3

TRIM5

-5V

+5V

Electronic circuit diagram of the magnetic sensor

Photograph of the completed measuring system data acquisition

software in PC and probe scanning system

Experimental Setup for Magnetic Sensor

Reference material Scanning System Software LabVIEW

Reference Material (1) Normal defects and PVCs

Longitudinal and transverse defects

Def W L D Remarks

1 02 500 0213 (20 ) Inner defects

2 02 500 0427 (40 )

3 02 500 0213 (20 )Outer defectsPVC(1018)4 02 500 0427 (40 )

5 02 500 0639 (60 )

6 02 500 0852 (80 )

7 02 500 0639 (60 ) Inner defects

8 02 500 0852 (80 )

- 1 and 2 are inner defects

- 345 and 6 are outer defects with PVC

- 7 and 8 are inner defects

PVC

PVC

Defect Defect

For longitudinal defects and PVC For circumferential defects and PVC

ECT is very difficult to detect circumferential defects

We can distinguish PVCs and defects and longitudinal and circumferential defects

Flux-gate Magnetometer

One core sensor Two core sensor

3-축 flux-gate Magnetometer의 계략도

Sensorpia Co

pro

cess

or(

AV

R)

Sensor 1

RS422

Interface

Mic

ro-p

roce

ssor(

AV

R)

Sensor 2

Sensor 3

Interface

조립된 마그네토미터의 사진

Sensorpia Co

Analog PCB

Digital PCB

Sensorpia Co선형도(linearity)

10

20

30

40

50

60

y-axis

Magnetometer Output (microT)

-60 -50 -40 -30 -20 -10 0 10 20 30 40 50 60

-60

-50

-40

-30

-20

-10

0

10

Y-axis y=099946 x+0015STD 106E-4

Magnetometer Output (

Applied Magnetic Field (microT)

마그네토미터의 noise 특성 Sensorpia Co

1

10

100

y-axis

Magnetometer noise (nT)

0 1 2 3 4 5 6

1E-4

1E-3

001

01

Magnetometer noise (nT)

Frequency (Hz)

Magnetometer for KoDSAT

-150 -100 -50 0 50 100 150

-15

-10

-5

0

5

10

15

Magnetic Moment (Am

2)

Current (mA)

After Thermal Cycle Test

Measured

Resistance 193 ohm

Photograph of Magnetic torquer

Photograph of KoDSAT

Photograph of

3-axis Fluxgate

Magnetometer

Photograph of Magnetic torquer

Application of magnetometer

Moon magnetic fieldmeasurement

Telescope with direction indication

Joule Effect (Magnetostriction)

ϕ2cosel

l=

∆

0=∆

+∆

+∆

b

b

a

a

l

l

Actuator using Terfenol-D

00

05

10

B (T)

800

1000

1200

1400

1600

Magnetostriction (ppm)

-100 -50 0 50 100

-10

-05

00

B (T)

H (kAm)

2 MPa

4 MPa

6 MPa

8 MPa

10 MPa

12 MPa

-100 -50 0 50 100

-200

0

200

400

600

Magnetostriction (ppm)

H (kAm)

2 MPa

4 MPa

6 MPa

8 MPa

10 MPa

12 MPa

600

700

800

900

1000

-4 -3 -2 -1 0 1 2 3 4

0

10

20

30

40

50

60

Displacement (m

icro meter)

I (A)

FIELD

9 kAm

12 kAm

16 kAm

20 kAm

24 kAm

38 kAm

-50 -40 -30 -20 -10 0 10 20 30 40 50

-100

0

100

200

300

400

500

L (PPM)

H (kAm)

9 kAm

12 kAm

16 kAm

20 kAm

24 kAm

38 kAm

Magnetostrictive displacement sensor

Hysteresis loops under

tensile stress σ

(a) Crystalline 68 NiFe

λs = +25 10-6

(b) crystalline pure Ni λs

= -35 10-6

Villari Effect ( Inverse of Joule Effect)

= -35 10-6

(c) amorphous Co-based

alloy

λs = -35 10-6

ϕσλ 2sin2

3sdotsdot= smeE

γ

Permeability depending on the stress

σλmicromicro

1

3

2

Y

J

so

s

r =

γ

Calculated magnetization curves under stress

Variation of magnetization curve by an applied

tensile force (Co-based amorphous alloy)

Alloy Requirement

Materials for magnetoelastic sensors

Why amorphous magnetic materials are important

Stress-strain curves of several materials

Coercivity and hardness of several materials

Principles of magnetoelastic sensors

Non-contact torque sensor

Principle of cross torductor torque

sensor and flux pattern of sensor

poles on the surface of a shaft

a) without and b)with torsional load

Equivalent magnetic circuit of

cross type torque sensor

Helices of principal tensile and compressive stress on the surface of

a shaft subjected to torsion [32] Correlated changes of permeability

are detected by four-branch yoke system with sensing coils 123

and 4 and a common excitation pole

Examples of torque sensors

Four-branch type torque sensor

heads Pole structures realized

by commercial multi-pole

ferrites 14 and 18 min in

diameter (diameter of sensor

h e a d 1 7 a n d 2 4 m m

respectively) respectively)

Principle of Ring Torductor torque transducer

(a b) Physical structure (c) evolution of the

shaft surface under the transducer poles A and BRing torductor for measuring

torque on ship propeller shafts

(shaft diameter ca 500 mm)

(Courtesy ASEA Brown

Boveri AG)

Principal designs of coaxial torque sensors

Schematic diagram of data processing

electronics of a torque sensor

Extensometer (a) Construction of strain sensing element using

amorphous ribbon wound core (b) configuration of lumped

windings

∆E effect of an amorphous FeNi-based

alloy (Fe40 Ni38 Mo4 B18) Hs saturation

field

Magnetically tunable delay line

Torque Sensors using Amorphous wire

Sixtus tonk효과(large Barkhausen효과)

Hysteresis loops of a Wiegand wire for different reset fields

Curie 온도 및Hopkinson효과

Relation between normalised

saturation polarisation and

normalised Curie temperature

Permeability of a Mn-Zn ferrite as

a function of temperature and field

strength

Conclusions

1) Magnetic sensor 는 자동차 공장자동화 항공우주 및 군사용으로많이 사용되고 있다

2) 새로운 소재개발은 자기센서의 성능개발에 직접적인 영향을 준다2) 새로운 소재개발은 자기센서의 성능개발에 직접적인 영향을 준다

3) 센서의 개발을 위해서는 다양한 전공지식이 요구된다

(물리학 재료공학 기계공학 전자공학)

4) 센서분야가 고부가가치를 창출하는 부품사업이다

5) 핵심부품을 생산하는 중소기업의 item으로도 적절하다

Applications of search coil magnetometer

Developed search coil magnetometer using amorphous ribbon

Experimental setup for the effective permeability measurement

Relative permeability depending on the numbers of ribbon(a)

and the air gap between ribbons

Relative permeability depending on the number of ribbons for the different air gap between ribbons

Relative permeability depending on the total number of ribbons for the different air gap between ribbons

10 pT

100 pT

1 pT

Noise spectrum of the developed search coil magnetometer

BJne

E xH

1minus=

neRH

1minus=

22 nP micromicro minus

Hall 효과

Bt

IRU H

HL =

2

22

)( he

eh

Hpne

nPR

micromicromicromicro

+

minus=

Rectangular Hall plate (cc1cc2 current constant sc1sc2

sensor constant I bias current U voltage drop UH Hall

voltage

Physics carrier concentration and kind of carrier measurement

Engineering magnetic field measurement

Current Measurement

Arrangement for noninvasive

current measurement using an iron

core The current to be measured

produces a proportional magnetic

field which can be measured in the

air gap

Characteristic curve produced by

the current

Arrangement for indirect noninvasive

current measurement using the

compensation principle An iron core as

represented in Figure 3-29 is held field

free by injection a current into a

compensating coil wound on the core

which offsets the field generated by the

current being measured The Hall effect

sensor in the air gap serves as a null

indicator

Circuit diagram for AC-power

measurement using a Hall effect

sensor

DC Power Measurement

Circuit diagram for DC-

power measurement using a

Hall effect sensor

Noncontact Position Sensing

Galvanomagnetic components for sensing the position of permanent magnets

and magnetically conductive materials

Current Sensor Based on Hall Sensor

and Magnetic Core for Hybrid Vehicle

KH Yeon1 SD Kim1 and D Son2 1Auto industry co14F Hanshin IT tower Guro Gu Seoul Korea2Hannam UniversityOjung dong 133 Daejeon Rep of Korea

i

Hall sensor

B

I

SB

ring core

B

I10

g

N

Bl S

micro

)( gtgtrmicro

gab core

Current Sensor Based on Hall

Sensor and Magnetic Core

Hall

Effect

Device

CurrentVoltage

applying for

Hall effect device

operation

Output

signals

Magnetic field

Occurred by

current measurement

Signal

process

circuits

Developed Current Sensor

Magnetic core

Hall sensor

PCB

25

30

35

40

45

50

Output voltage V

Current sensor(Open loop type)

Temp 25C

400A model

+400 ~ -400A

SD 000128

Linearity 003

Linearity of the sensor

Characteristics of the Current Sensors

1000A 10 V power supply

-500 -400 -300 -200 -100 0 100 200 300 400 500

00

05

10

15

20

Output voltage V

current A

Temperature 25Linearity 003

Measuring range -400A ~ +400A

1000A Electronic Load

-3

0

3

6

9

12

15

18

dB

Current sensor

DV2 PCB 24pF

40Aturns

Frequency bandwidth

Gain bandwidth 3 MHz

Current 10 A

Temperature 25

Frequency bandwidth 100 kHz

Sensor output voltage vs frequency

at applied current of 40 Aturns

1 10 100

-18

-15

-12

-9

-6

Frequency kHz 측정온도 25

주파수특성 30kHz 이상(3dB 기준)

측정전류 40Aturns(4A 10턴)

측정주파수 100Hz ~ 100kHz

Temperature 25Current 40Aturns

Frequency range 100 Hz ~ 100 kHz

What is Magnetoresistance

Magnetoresistance effect(AMR)

θθθ 2cos2

12sin12cos(

22 minusminus+∆asymp∆ xxxmx hhhRR

32 minusasymp∆ ρρ New effect GMR CMR and GMI

10 ge∆ ρρ

Two bridge configuration for

rotational angle measurement

measurement angle more than 180o

자동차 Engine Management System

Inductive and Eddy Current

Sensors Excited by Permanent Magnets

tNtU dd)( φsdotminus=

construction of an inductive

sensor (courtesy VDO Adolf sensor (courtesy VDO Adolf

Schindling AG)

1) constant socket

2) terminal package

3) permanent magnet

4) cap

5) soft magnetic core

6) coil

7) plate

8) blade connector

γγ

Sensor with yoke Change in the magnetic flux with

varying air gap Continuous lines

minimum air gap dashed lines

maximum air gap

C-shaped sensor

Sensor with radially

magnetized

permanent magnet

Signal Conditioning

Output voltage U of a DC-excited sensor with permanent

magnets when a single iron object passes by

Schematic electrical diagram of an inductive sensor

Linear Variable Differential Transformer

AC-Excited Sensors for Linear Movement

Principle of construction of an LVDT

Electrical circuit of an LVDT

tIMtNU dd dd sdotminus=sdotminus= φ

tIMtIMUUU dd dd 1212 sdotminussdot=minus=

tIMMU dd)( 12 sdotminus=

)(12 xMMMM =minus=

tIxMU dd)( sdot= tI

UxM

dd)( =

Signal Conditioning

power supply

carrier gen

autoampcontrol

LVDTcarrieramp

demod-ulator

phase

shifter

power supply

carrier gen

passivedemod-ulator

LVDTDCamp

Block diagram of a carrier amplifier system

Block diagram of a DC amplifier system

Variable Inductive Sensors

Principle of construction

of the VLP sensor

Principle of a bridge

circuit

lANL r 20 sdotsdotsdot= micromicro

21 BA UUU minus=

21)i(ii( 211 minus+sdot= LLLUU BA ωωω

)21))()((( minus∆minus+∆+∆+sdot= LLLLLLUU BA

)212)(( minus∆+sdot= LLLUU )212)(( minus∆+sdot= LLLUU BA

LLUU BA 21 ∆sdotsdot=

llLL ∆sdot=∆ d d

llLLUU BA ∆sdotsdot= d d)2(1

Applications and Properties

Principle of a construction of a force transducer

(courtesy Hottinger Baldwin Messtechnik)

Vibrationacceleration sensor

Signal Conditioning

Schematic electrical diagram of a force transducer connected with an

amplifier (courtesy Hottinger Baldwin Messtechnik GmbH)

Variable Gap Sensors

)( FeFe2

0 LLllANL micromicromicro +sdotsdot=

FeFe2

0max lANL sdotsdotsdot= micromicro

Construction of a variable gap sensor

Characteristic of a variable gap sensor

Construction of a differential

cross-anchor sensor

Output voltage U versus core

position x plusmn a limits of the

linear rage

Applications of differential cross-anchor sensors

AC-excited Sensors for Rotary Movements

Principle of construction of a synchro

α cos10 sdotsdot= UKU y

)120-( cos10 degsdotsdot= αUKU z

)240-( cos10 degsdotsdot= αUKU x

)120-( sin3100 degsdotsdotsdot=minus= αKUUUU yxyx

)240-( sin3100 degsdotsdotsdot=minus= αKUUUU zyzy

α sin3100 sdotsdotsdot=minus= KUUUU xzxz

Application to the Torque Sensor

Principle of construction of a torque-type synchro

Torque versus angular

difference

)( sin~ rt αα minussdotKM

)( cos~ rt1r αα minussdotUU

Principle of construction of a control-type sensor

Output voltage versus

angular difference

Principle of construction of a differential sychro

Eddy Current Sensors

tBE dd curl minus=JH = curl

0 div =BH(H)B sdot= micro

E(E)J sdot= σ

A B curl= A B curl=

tdd- A E =

)dd( tAJ minus= σ

tdd curl curl AA σmicro minus=

AA) σωmicro iminus= curl )(curl(1

AA) σωmicro i=∆)((1

Eddy Current Tachometer

Construction of a speedometer (courtesy VDO Adolf Schinding AG) 1) spindle 2) bearing

3) holding spring 4) iron yoke 5) eddy current cup 6) shaft of the magnet 7) support of

the magnet 8) temperature compensation 9) permanent magnet 10) torsion spring

Proximity Sensors

Schematic diagram of a proximity sensor

Output current of a proximity switch versus distance

Inductive Flowmeters

)( Btimessdot= υqF

EqF sdot=BE times=υ

)(ds Btimes== υEU )(ds Btimes== υEU

)( Bd timessdot= υU

Bsdotsdotsdot= υdKU

Development of magnetic phase detection

sensor for steam generator tube

Dirac Son1 Kwan-Sang Ryu2 Duck-Gun Park3

1Hannam University Daejeon Rep of Korea2Korea Research Institute of Standards and Science Daejeon Rep of Korea3KoreaAtomic Energy Research Institute Daejeon Rep of Korea

Introduction

The layout of pressurized water reactor (PWR) components

Primary side Secondary side (non-radioactive side)(radioactive side)

The Structure of SG(Steam Generator)(degradation mechanism)

Secondary SidePrimary Side

SCC

A B

A-B

Steam outlet

Anti-vibration

SCC

Fretting

Wall thinning

IGA

U-bend

In commercial power plants SG- height up to 21 m - weight up to 800 tons - 2~4 sets of SG were installed - SG can contain from 3000 to

16000 tubes each about 20 mmin diameter

Primary coolant outlet Primary coolant inlet

Anti-vibrationbars

Tubesupportplate

Tubesheet

IGA

SCC

Pitting

SCC

Inside Tubesheet

Top of Tubesheet

by SSHwang of KAERI

Denting

Sludge pile

in diameter

The SGT is made of nickel basedInconel alloy which is composed of 75 Ni 165Cr and 815Fe

-Degradation mechanism corrosion pitting denting inter granular attack

-Inspection Eddy current Testing(ECT)

Permeability Variation Clusters (PVC)

(Ferro-magnetic phase)

-005

000

005

010

015

m (emug)

1-1

-002

000

002

004

006

008

m (emug)

1-2

-1000 -500 0 500 1000

-015

-010

-005

H ( Am )

-1000 -500 0 500 1000

-006

-004

-002

H ( Am )

The hystresis loop in the fragment of PVC parts of Kori-1 retired SG tube

-004

-002

000

002

004

006

M (emug)

Inconel 600 tested at RT

under tensile stress

1 2 3

4 5 6

7 8 9-004

-002

000

002

004

006

M(emug)

Inconel 600 Heat treated at

602 oC under tensile stress

1 2 3

How can we detect magnetic phase

(PVC)selectively from the flaws in SGT

-3000 -2000 -1000 0 1000 2000 3000

-006

H (Oe)

7 8 9

10 11 12

-3000 -2000 -1000 0 1000 2000 3000

-006

-004

H(Oe)

4 5 6

7 8 9

The hysteresis loop of the tensile tested specimen at room temperature (a) and tensile tested at high temperature (b)

The magnetic phase can be created under the high temperature andpressure conditions which is correspond to the stress corrosion crackingin the SG tube in the NPP(Bruemmer SM Charlot LA amp Henager CH (1988) Corrosion 782)

Principle of ECT

If we can separate magnetic phase selectively from the

flaws using magnetic sensor the reliability of EC in SGT

inspection will be greatly enhanced

Structure of the permeability

sensor

Dimension and photograph of U-shape

sensing yoke

Design of Magnetic Sensor for PVC

sensor sensing yoke

Photograph of the completed sensor front side (above) and rear side (bottom)

R11R12

R10

R8

R6

R9

R13

R7

R14

C18

1 n

C17

C20

C21

D2

DIODE

SIN COS

-

+

U-2A

4

13

2

-

+

U-2B

75

6

8

-

+

U-3A

13

2

8

+5VC19

104

+5V

Schematic diagram of the sensor system

Electronic Circuit of Magnetic Sensor

R20

R

R21

R

-

+

U5AD797

3

26

74

U6

D1

S12

GND3

+VCC4VCC5

IN6

-VCC7

S28

C41

R13

R26

R18

R25

R2210 Ω

R16

R14

R17

10 k

R15

R27

R32

R28

R33

R29

R34

5 k

R30

C29

C37

104

C32473

C39473C40

104

C33

104

C21

104C23

104

C25

104

C26

104

C30

104

C31

104

C35

104

C36

104

C27

104

C28

104

C34

104

C38

104

D3

DIODE

L1

1

2

L2

1

2

L3

1

2

4

-

+

U-4A

4

13

2

-

+

U-4B

75

6

8

-

+

U-5A

4

13

2

-

+

U-5B

75

6

8

-

+

U-6A

4

13

2

-

+

U-6B

75

6

8

C22

104

-5V

+5V

+5V

+5V

+5V

+5V

+5V

U7

D1

S12

GND3

+VCC4

VCC5

IN6

-VCC7

S28

+5V

-5V

-5V

-5V

-5V

-5V

-5V

-5V

-5V

R19

R24

R

R23

R

C24

OUT(X)

OUT(Y)

R1

20 kR210 k

R3

20 kR410 k

C1

104

C8

104

REF43

OUT(X)

OUT(Y)

REF43

U2

+Vcc1

CH02

CH13

CH24

CH35

COMM6

SHDN7

Vref8

+Vcc9

GND10

GND11

DOUT12BUSY13DIN14CS15

DIN16

-

+

U-1A

13

2

8

-

+

U-1B

4

75

6

C410 uF

C5104

DOUT

C210uF

C6104

C3104

DCLK

C7104

DIN

C10

01uF

CS

BUSY

C14 10uF

J1

CON6

123456

D1

DIODE

R5

47K

C9

10uF

C1310uF

Y1

OSC

OUT3

GND2

VCC4

U3

RSTVPP1

GND10

VCC20

XTAL15

XTAL24

P10AIN012P11AIN113P1214P1315P1416P1517P1618P1719

P30RXD2

P31TXD3

P32INT06

P33INT17

P34T08

P35T19

P3711

U4

C1+1

C1-3

C2+4

C2-5

VCC16

GND15

V+2

V-6

R1OUT12

R2OUT9

T1IN11

T2IN10

R1IN13

R2IN8

T1OUT14

T2OUT7

C12 10uF

C16

01uF

C15 10uF

C11

01uF

-5V

+5V

+5V

+5V

+5V

+5V

+5V

+5V

RST

OSC

OSC

RST

DCLKCSDINBUSYDOUT

U1

IN2

GND

4

OUT6

TEMP3

TRIM5

-5V

+5V

Electronic circuit diagram of the magnetic sensor

Photograph of the completed measuring system data acquisition

software in PC and probe scanning system

Experimental Setup for Magnetic Sensor

Reference material Scanning System Software LabVIEW

Reference Material (1) Normal defects and PVCs

Longitudinal and transverse defects

Def W L D Remarks

1 02 500 0213 (20 ) Inner defects

2 02 500 0427 (40 )

3 02 500 0213 (20 )Outer defectsPVC(1018)4 02 500 0427 (40 )

5 02 500 0639 (60 )

6 02 500 0852 (80 )

7 02 500 0639 (60 ) Inner defects

8 02 500 0852 (80 )

- 1 and 2 are inner defects

- 345 and 6 are outer defects with PVC

- 7 and 8 are inner defects

PVC

PVC

Defect Defect

For longitudinal defects and PVC For circumferential defects and PVC

ECT is very difficult to detect circumferential defects

We can distinguish PVCs and defects and longitudinal and circumferential defects

Flux-gate Magnetometer

One core sensor Two core sensor

3-축 flux-gate Magnetometer의 계략도

Sensorpia Co

pro

cess

or(

AV

R)

Sensor 1

RS422

Interface

Mic

ro-p

roce

ssor(

AV

R)

Sensor 2

Sensor 3

Interface

조립된 마그네토미터의 사진

Sensorpia Co

Analog PCB

Digital PCB

Sensorpia Co선형도(linearity)

10

20

30

40

50

60

y-axis

Magnetometer Output (microT)

-60 -50 -40 -30 -20 -10 0 10 20 30 40 50 60

-60

-50

-40

-30

-20

-10

0

10

Y-axis y=099946 x+0015STD 106E-4

Magnetometer Output (

Applied Magnetic Field (microT)

마그네토미터의 noise 특성 Sensorpia Co

1

10

100

y-axis

Magnetometer noise (nT)

0 1 2 3 4 5 6

1E-4

1E-3

001

01

Magnetometer noise (nT)

Frequency (Hz)

Magnetometer for KoDSAT

-150 -100 -50 0 50 100 150

-15

-10

-5

0

5

10

15

Magnetic Moment (Am

2)

Current (mA)

After Thermal Cycle Test

Measured

Resistance 193 ohm

Photograph of Magnetic torquer

Photograph of KoDSAT

Photograph of

3-axis Fluxgate

Magnetometer

Photograph of Magnetic torquer

Application of magnetometer

Moon magnetic fieldmeasurement

Telescope with direction indication

Joule Effect (Magnetostriction)

ϕ2cosel

l=

∆

0=∆

+∆

+∆

b

b

a

a

l

l

Actuator using Terfenol-D

00

05

10

B (T)

800

1000

1200

1400

1600

Magnetostriction (ppm)

-100 -50 0 50 100

-10

-05

00

B (T)

H (kAm)

2 MPa

4 MPa

6 MPa

8 MPa

10 MPa

12 MPa

-100 -50 0 50 100

-200

0

200

400

600

Magnetostriction (ppm)

H (kAm)

2 MPa

4 MPa

6 MPa

8 MPa

10 MPa

12 MPa

600

700

800

900

1000

-4 -3 -2 -1 0 1 2 3 4

0

10

20

30

40

50

60

Displacement (m

icro meter)

I (A)

FIELD

9 kAm

12 kAm

16 kAm

20 kAm

24 kAm

38 kAm

-50 -40 -30 -20 -10 0 10 20 30 40 50

-100

0

100

200

300

400

500

L (PPM)

H (kAm)

9 kAm

12 kAm

16 kAm

20 kAm

24 kAm

38 kAm

Magnetostrictive displacement sensor

Hysteresis loops under

tensile stress σ

(a) Crystalline 68 NiFe

λs = +25 10-6

(b) crystalline pure Ni λs

= -35 10-6

Villari Effect ( Inverse of Joule Effect)

= -35 10-6

(c) amorphous Co-based

alloy

λs = -35 10-6

ϕσλ 2sin2

3sdotsdot= smeE

γ

Permeability depending on the stress

σλmicromicro

1

3

2

Y

J

so

s

r =

γ

Calculated magnetization curves under stress

Variation of magnetization curve by an applied

tensile force (Co-based amorphous alloy)

Alloy Requirement

Materials for magnetoelastic sensors

Why amorphous magnetic materials are important

Stress-strain curves of several materials

Coercivity and hardness of several materials

Principles of magnetoelastic sensors

Non-contact torque sensor

Principle of cross torductor torque

sensor and flux pattern of sensor

poles on the surface of a shaft

a) without and b)with torsional load

Equivalent magnetic circuit of

cross type torque sensor

Helices of principal tensile and compressive stress on the surface of

a shaft subjected to torsion [32] Correlated changes of permeability

are detected by four-branch yoke system with sensing coils 123

and 4 and a common excitation pole

Examples of torque sensors

Four-branch type torque sensor

heads Pole structures realized

by commercial multi-pole

ferrites 14 and 18 min in

diameter (diameter of sensor

h e a d 1 7 a n d 2 4 m m

respectively) respectively)

Principle of Ring Torductor torque transducer

(a b) Physical structure (c) evolution of the

shaft surface under the transducer poles A and BRing torductor for measuring

torque on ship propeller shafts

(shaft diameter ca 500 mm)

(Courtesy ASEA Brown

Boveri AG)

Principal designs of coaxial torque sensors

Schematic diagram of data processing

electronics of a torque sensor

Extensometer (a) Construction of strain sensing element using

amorphous ribbon wound core (b) configuration of lumped

windings

∆E effect of an amorphous FeNi-based

alloy (Fe40 Ni38 Mo4 B18) Hs saturation

field

Magnetically tunable delay line

Torque Sensors using Amorphous wire

Sixtus tonk효과(large Barkhausen효과)

Hysteresis loops of a Wiegand wire for different reset fields

Curie 온도 및Hopkinson효과

Relation between normalised

saturation polarisation and

normalised Curie temperature

Permeability of a Mn-Zn ferrite as

a function of temperature and field

strength

Conclusions

1) Magnetic sensor 는 자동차 공장자동화 항공우주 및 군사용으로많이 사용되고 있다

2) 새로운 소재개발은 자기센서의 성능개발에 직접적인 영향을 준다2) 새로운 소재개발은 자기센서의 성능개발에 직접적인 영향을 준다

3) 센서의 개발을 위해서는 다양한 전공지식이 요구된다

(물리학 재료공학 기계공학 전자공학)

4) 센서분야가 고부가가치를 창출하는 부품사업이다

5) 핵심부품을 생산하는 중소기업의 item으로도 적절하다

Developed search coil magnetometer using amorphous ribbon

Experimental setup for the effective permeability measurement

Relative permeability depending on the numbers of ribbon(a)

and the air gap between ribbons

Relative permeability depending on the number of ribbons for the different air gap between ribbons

Relative permeability depending on the total number of ribbons for the different air gap between ribbons

10 pT

100 pT

1 pT

Noise spectrum of the developed search coil magnetometer

BJne

E xH

1minus=

neRH

1minus=

22 nP micromicro minus

Hall 효과

Bt

IRU H

HL =

2

22

)( he

eh

Hpne

nPR

micromicromicromicro

+

minus=

Rectangular Hall plate (cc1cc2 current constant sc1sc2

sensor constant I bias current U voltage drop UH Hall

voltage

Physics carrier concentration and kind of carrier measurement

Engineering magnetic field measurement

Current Measurement

Arrangement for noninvasive

current measurement using an iron

core The current to be measured

produces a proportional magnetic

field which can be measured in the

air gap

Characteristic curve produced by

the current

Arrangement for indirect noninvasive

current measurement using the

compensation principle An iron core as

represented in Figure 3-29 is held field

free by injection a current into a

compensating coil wound on the core

which offsets the field generated by the

current being measured The Hall effect

sensor in the air gap serves as a null

indicator

Circuit diagram for AC-power

measurement using a Hall effect

sensor

DC Power Measurement

Circuit diagram for DC-

power measurement using a

Hall effect sensor

Noncontact Position Sensing

Galvanomagnetic components for sensing the position of permanent magnets

and magnetically conductive materials

Current Sensor Based on Hall Sensor

and Magnetic Core for Hybrid Vehicle

KH Yeon1 SD Kim1 and D Son2 1Auto industry co14F Hanshin IT tower Guro Gu Seoul Korea2Hannam UniversityOjung dong 133 Daejeon Rep of Korea

i

Hall sensor

B

I

SB

ring core

B

I10

g

N

Bl S

micro

)( gtgtrmicro

gab core

Current Sensor Based on Hall

Sensor and Magnetic Core

Hall

Effect

Device

CurrentVoltage

applying for

Hall effect device

operation

Output

signals

Magnetic field

Occurred by

current measurement

Signal

process

circuits

Developed Current Sensor

Magnetic core

Hall sensor

PCB

25

30

35

40

45

50

Output voltage V

Current sensor(Open loop type)

Temp 25C

400A model

+400 ~ -400A

SD 000128

Linearity 003

Linearity of the sensor

Characteristics of the Current Sensors

1000A 10 V power supply

-500 -400 -300 -200 -100 0 100 200 300 400 500

00

05

10

15

20

Output voltage V

current A

Temperature 25Linearity 003

Measuring range -400A ~ +400A

1000A Electronic Load

-3

0

3

6

9

12

15

18

dB

Current sensor

DV2 PCB 24pF

40Aturns

Frequency bandwidth

Gain bandwidth 3 MHz

Current 10 A

Temperature 25

Frequency bandwidth 100 kHz

Sensor output voltage vs frequency

at applied current of 40 Aturns

1 10 100

-18

-15

-12

-9

-6

Frequency kHz 측정온도 25

주파수특성 30kHz 이상(3dB 기준)

측정전류 40Aturns(4A 10턴)

측정주파수 100Hz ~ 100kHz

Temperature 25Current 40Aturns

Frequency range 100 Hz ~ 100 kHz

What is Magnetoresistance

Magnetoresistance effect(AMR)

θθθ 2cos2

12sin12cos(

22 minusminus+∆asymp∆ xxxmx hhhRR

32 minusasymp∆ ρρ New effect GMR CMR and GMI

10 ge∆ ρρ

Two bridge configuration for

rotational angle measurement

measurement angle more than 180o

자동차 Engine Management System

Inductive and Eddy Current

Sensors Excited by Permanent Magnets

tNtU dd)( φsdotminus=

construction of an inductive

sensor (courtesy VDO Adolf sensor (courtesy VDO Adolf

Schindling AG)

1) constant socket

2) terminal package

3) permanent magnet

4) cap

5) soft magnetic core

6) coil

7) plate

8) blade connector

γγ

Sensor with yoke Change in the magnetic flux with

varying air gap Continuous lines

minimum air gap dashed lines

maximum air gap

C-shaped sensor

Sensor with radially

magnetized

permanent magnet

Signal Conditioning

Output voltage U of a DC-excited sensor with permanent

magnets when a single iron object passes by

Schematic electrical diagram of an inductive sensor

Linear Variable Differential Transformer

AC-Excited Sensors for Linear Movement

Principle of construction of an LVDT

Electrical circuit of an LVDT

tIMtNU dd dd sdotminus=sdotminus= φ

tIMtIMUUU dd dd 1212 sdotminussdot=minus=

tIMMU dd)( 12 sdotminus=

)(12 xMMMM =minus=

tIxMU dd)( sdot= tI

UxM

dd)( =

Signal Conditioning

power supply

carrier gen

autoampcontrol

LVDTcarrieramp

demod-ulator

phase

shifter

power supply

carrier gen

passivedemod-ulator

LVDTDCamp

Block diagram of a carrier amplifier system

Block diagram of a DC amplifier system

Variable Inductive Sensors

Principle of construction

of the VLP sensor

Principle of a bridge

circuit

lANL r 20 sdotsdotsdot= micromicro

21 BA UUU minus=

21)i(ii( 211 minus+sdot= LLLUU BA ωωω

)21))()((( minus∆minus+∆+∆+sdot= LLLLLLUU BA

)212)(( minus∆+sdot= LLLUU )212)(( minus∆+sdot= LLLUU BA

LLUU BA 21 ∆sdotsdot=

llLL ∆sdot=∆ d d

llLLUU BA ∆sdotsdot= d d)2(1

Applications and Properties

Principle of a construction of a force transducer

(courtesy Hottinger Baldwin Messtechnik)

Vibrationacceleration sensor

Signal Conditioning

Schematic electrical diagram of a force transducer connected with an

amplifier (courtesy Hottinger Baldwin Messtechnik GmbH)

Variable Gap Sensors

)( FeFe2

0 LLllANL micromicromicro +sdotsdot=

FeFe2

0max lANL sdotsdotsdot= micromicro

Construction of a variable gap sensor

Characteristic of a variable gap sensor

Construction of a differential

cross-anchor sensor

Output voltage U versus core

position x plusmn a limits of the

linear rage

Applications of differential cross-anchor sensors

AC-excited Sensors for Rotary Movements

Principle of construction of a synchro

α cos10 sdotsdot= UKU y

)120-( cos10 degsdotsdot= αUKU z

)240-( cos10 degsdotsdot= αUKU x

)120-( sin3100 degsdotsdotsdot=minus= αKUUUU yxyx

)240-( sin3100 degsdotsdotsdot=minus= αKUUUU zyzy

α sin3100 sdotsdotsdot=minus= KUUUU xzxz

Application to the Torque Sensor

Principle of construction of a torque-type synchro

Torque versus angular

difference

)( sin~ rt αα minussdotKM

)( cos~ rt1r αα minussdotUU

Principle of construction of a control-type sensor

Output voltage versus

angular difference

Principle of construction of a differential sychro

Eddy Current Sensors

tBE dd curl minus=JH = curl

0 div =BH(H)B sdot= micro

E(E)J sdot= σ

A B curl= A B curl=

tdd- A E =

)dd( tAJ minus= σ

tdd curl curl AA σmicro minus=

AA) σωmicro iminus= curl )(curl(1

AA) σωmicro i=∆)((1

Eddy Current Tachometer

Construction of a speedometer (courtesy VDO Adolf Schinding AG) 1) spindle 2) bearing

3) holding spring 4) iron yoke 5) eddy current cup 6) shaft of the magnet 7) support of

the magnet 8) temperature compensation 9) permanent magnet 10) torsion spring

Proximity Sensors

Schematic diagram of a proximity sensor

Output current of a proximity switch versus distance

Inductive Flowmeters

)( Btimessdot= υqF

EqF sdot=BE times=υ

)(ds Btimes== υEU )(ds Btimes== υEU

)( Bd timessdot= υU

Bsdotsdotsdot= υdKU

Development of magnetic phase detection

sensor for steam generator tube

Dirac Son1 Kwan-Sang Ryu2 Duck-Gun Park3

1Hannam University Daejeon Rep of Korea2Korea Research Institute of Standards and Science Daejeon Rep of Korea3KoreaAtomic Energy Research Institute Daejeon Rep of Korea

Introduction

The layout of pressurized water reactor (PWR) components

Primary side Secondary side (non-radioactive side)(radioactive side)

The Structure of SG(Steam Generator)(degradation mechanism)

Secondary SidePrimary Side

SCC

A B

A-B

Steam outlet

Anti-vibration

SCC

Fretting

Wall thinning

IGA

U-bend

In commercial power plants SG- height up to 21 m - weight up to 800 tons - 2~4 sets of SG were installed - SG can contain from 3000 to

16000 tubes each about 20 mmin diameter

Primary coolant outlet Primary coolant inlet

Anti-vibrationbars

Tubesupportplate

Tubesheet

IGA

SCC

Pitting

SCC

Inside Tubesheet

Top of Tubesheet

by SSHwang of KAERI

Denting

Sludge pile

in diameter

The SGT is made of nickel basedInconel alloy which is composed of 75 Ni 165Cr and 815Fe

-Degradation mechanism corrosion pitting denting inter granular attack

-Inspection Eddy current Testing(ECT)

Permeability Variation Clusters (PVC)

(Ferro-magnetic phase)

-005

000

005

010

015

m (emug)

1-1

-002

000

002

004

006

008

m (emug)

1-2

-1000 -500 0 500 1000

-015

-010

-005

H ( Am )

-1000 -500 0 500 1000

-006

-004

-002

H ( Am )

The hystresis loop in the fragment of PVC parts of Kori-1 retired SG tube

-004

-002

000

002

004

006

M (emug)

Inconel 600 tested at RT

under tensile stress

1 2 3

4 5 6

7 8 9-004

-002

000

002

004

006

M(emug)

Inconel 600 Heat treated at

602 oC under tensile stress

1 2 3

How can we detect magnetic phase

(PVC)selectively from the flaws in SGT

-3000 -2000 -1000 0 1000 2000 3000

-006

H (Oe)

7 8 9

10 11 12

-3000 -2000 -1000 0 1000 2000 3000

-006

-004

H(Oe)

4 5 6

7 8 9

The hysteresis loop of the tensile tested specimen at room temperature (a) and tensile tested at high temperature (b)

The magnetic phase can be created under the high temperature andpressure conditions which is correspond to the stress corrosion crackingin the SG tube in the NPP(Bruemmer SM Charlot LA amp Henager CH (1988) Corrosion 782)

Principle of ECT

If we can separate magnetic phase selectively from the

flaws using magnetic sensor the reliability of EC in SGT

inspection will be greatly enhanced

Structure of the permeability

sensor

Dimension and photograph of U-shape

sensing yoke

Design of Magnetic Sensor for PVC

sensor sensing yoke

Photograph of the completed sensor front side (above) and rear side (bottom)

R11R12

R10

R8

R6

R9

R13

R7

R14

C18

1 n

C17

C20

C21

D2

DIODE

SIN COS

-

+

U-2A

4

13

2

-

+

U-2B

75

6

8

-

+

U-3A

13

2

8

+5VC19

104

+5V

Schematic diagram of the sensor system

Electronic Circuit of Magnetic Sensor

R20

R

R21

R

-

+

U5AD797

3

26

74

U6

D1

S12

GND3

+VCC4VCC5

IN6

-VCC7

S28

C41

R13

R26

R18

R25

R2210 Ω

R16

R14

R17

10 k

R15

R27

R32

R28

R33

R29

R34

5 k

R30

C29

C37

104

C32473

C39473C40

104

C33

104

C21

104C23

104

C25

104

C26

104

C30

104

C31

104

C35

104

C36

104

C27

104

C28

104

C34

104

C38

104

D3

DIODE

L1

1

2

L2

1

2

L3

1

2

4

-

+

U-4A

4

13

2

-

+

U-4B

75

6

8

-

+

U-5A

4

13

2

-

+

U-5B

75

6

8

-

+

U-6A

4

13

2

-

+

U-6B

75

6

8

C22

104

-5V

+5V

+5V

+5V

+5V

+5V

+5V

U7

D1

S12

GND3

+VCC4

VCC5

IN6

-VCC7

S28

+5V

-5V

-5V

-5V

-5V

-5V

-5V

-5V

-5V

R19

R24

R

R23

R

C24

OUT(X)

OUT(Y)

R1

20 kR210 k

R3

20 kR410 k

C1

104

C8

104

REF43

OUT(X)

OUT(Y)

REF43

U2

+Vcc1

CH02

CH13

CH24

CH35

COMM6

SHDN7

Vref8

+Vcc9

GND10

GND11

DOUT12BUSY13DIN14CS15

DIN16

-

+

U-1A

13

2

8

-

+

U-1B

4

75

6

C410 uF

C5104

DOUT

C210uF

C6104

C3104

DCLK

C7104

DIN

C10

01uF

CS

BUSY

C14 10uF

J1

CON6

123456

D1

DIODE

R5

47K

C9

10uF

C1310uF

Y1

OSC

OUT3

GND2

VCC4

U3

RSTVPP1

GND10

VCC20

XTAL15

XTAL24

P10AIN012P11AIN113P1214P1315P1416P1517P1618P1719

P30RXD2

P31TXD3

P32INT06

P33INT17

P34T08

P35T19

P3711

U4

C1+1

C1-3

C2+4

C2-5

VCC16

GND15

V+2

V-6

R1OUT12

R2OUT9

T1IN11

T2IN10

R1IN13

R2IN8

T1OUT14

T2OUT7

C12 10uF

C16

01uF

C15 10uF

C11

01uF

-5V

+5V

+5V

+5V

+5V

+5V

+5V

+5V

RST

OSC

OSC

RST

DCLKCSDINBUSYDOUT

U1

IN2

GND

4

OUT6

TEMP3

TRIM5

-5V

+5V

Electronic circuit diagram of the magnetic sensor

Photograph of the completed measuring system data acquisition

software in PC and probe scanning system

Experimental Setup for Magnetic Sensor

Reference material Scanning System Software LabVIEW

Reference Material (1) Normal defects and PVCs

Longitudinal and transverse defects

Def W L D Remarks

1 02 500 0213 (20 ) Inner defects

2 02 500 0427 (40 )

3 02 500 0213 (20 )Outer defectsPVC(1018)4 02 500 0427 (40 )

5 02 500 0639 (60 )

6 02 500 0852 (80 )

7 02 500 0639 (60 ) Inner defects

8 02 500 0852 (80 )

- 1 and 2 are inner defects

- 345 and 6 are outer defects with PVC

- 7 and 8 are inner defects

PVC

PVC

Defect Defect

For longitudinal defects and PVC For circumferential defects and PVC

ECT is very difficult to detect circumferential defects

We can distinguish PVCs and defects and longitudinal and circumferential defects

Flux-gate Magnetometer

One core sensor Two core sensor

3-축 flux-gate Magnetometer의 계략도

Sensorpia Co

pro

cess

or(

AV

R)

Sensor 1

RS422

Interface

Mic

ro-p

roce

ssor(

AV

R)

Sensor 2

Sensor 3

Interface

조립된 마그네토미터의 사진

Sensorpia Co

Analog PCB

Digital PCB

Sensorpia Co선형도(linearity)

10

20

30

40

50

60

y-axis

Magnetometer Output (microT)

-60 -50 -40 -30 -20 -10 0 10 20 30 40 50 60

-60

-50

-40

-30

-20

-10

0

10

Y-axis y=099946 x+0015STD 106E-4

Magnetometer Output (

Applied Magnetic Field (microT)

마그네토미터의 noise 특성 Sensorpia Co

1

10

100

y-axis

Magnetometer noise (nT)

0 1 2 3 4 5 6

1E-4

1E-3

001

01

Magnetometer noise (nT)

Frequency (Hz)

Magnetometer for KoDSAT

-150 -100 -50 0 50 100 150

-15

-10

-5

0

5

10

15

Magnetic Moment (Am

2)

Current (mA)

After Thermal Cycle Test

Measured

Resistance 193 ohm

Photograph of Magnetic torquer

Photograph of KoDSAT

Photograph of

3-axis Fluxgate

Magnetometer

Photograph of Magnetic torquer

Application of magnetometer

Moon magnetic fieldmeasurement

Telescope with direction indication

Joule Effect (Magnetostriction)

ϕ2cosel

l=

∆

0=∆

+∆

+∆

b

b

a

a

l

l

Actuator using Terfenol-D

00

05

10

B (T)

800

1000

1200

1400

1600

Magnetostriction (ppm)

-100 -50 0 50 100

-10

-05

00

B (T)

H (kAm)

2 MPa

4 MPa

6 MPa

8 MPa

10 MPa

12 MPa

-100 -50 0 50 100

-200

0

200

400

600

Magnetostriction (ppm)

H (kAm)

2 MPa

4 MPa

6 MPa

8 MPa

10 MPa

12 MPa

600

700

800

900

1000

-4 -3 -2 -1 0 1 2 3 4

0

10

20

30

40

50

60

Displacement (m

icro meter)

I (A)

FIELD

9 kAm

12 kAm

16 kAm

20 kAm

24 kAm

38 kAm

-50 -40 -30 -20 -10 0 10 20 30 40 50

-100

0

100

200

300

400

500

L (PPM)

H (kAm)

9 kAm

12 kAm

16 kAm

20 kAm

24 kAm

38 kAm

Magnetostrictive displacement sensor

Hysteresis loops under

tensile stress σ

(a) Crystalline 68 NiFe

λs = +25 10-6

(b) crystalline pure Ni λs

= -35 10-6

Villari Effect ( Inverse of Joule Effect)

= -35 10-6

(c) amorphous Co-based

alloy

λs = -35 10-6

ϕσλ 2sin2

3sdotsdot= smeE

γ

Permeability depending on the stress

σλmicromicro

1

3

2

Y

J

so

s

r =

γ

Calculated magnetization curves under stress

Variation of magnetization curve by an applied

tensile force (Co-based amorphous alloy)

Alloy Requirement

Materials for magnetoelastic sensors

Why amorphous magnetic materials are important

Stress-strain curves of several materials

Coercivity and hardness of several materials

Principles of magnetoelastic sensors

Non-contact torque sensor

Principle of cross torductor torque

sensor and flux pattern of sensor

poles on the surface of a shaft

a) without and b)with torsional load

Equivalent magnetic circuit of

cross type torque sensor

Helices of principal tensile and compressive stress on the surface of

a shaft subjected to torsion [32] Correlated changes of permeability

are detected by four-branch yoke system with sensing coils 123

and 4 and a common excitation pole

Examples of torque sensors

Four-branch type torque sensor

heads Pole structures realized

by commercial multi-pole

ferrites 14 and 18 min in

diameter (diameter of sensor

h e a d 1 7 a n d 2 4 m m

respectively) respectively)

Principle of Ring Torductor torque transducer

(a b) Physical structure (c) evolution of the

shaft surface under the transducer poles A and BRing torductor for measuring

torque on ship propeller shafts

(shaft diameter ca 500 mm)

(Courtesy ASEA Brown

Boveri AG)

Principal designs of coaxial torque sensors

Schematic diagram of data processing

electronics of a torque sensor

Extensometer (a) Construction of strain sensing element using

amorphous ribbon wound core (b) configuration of lumped

windings

∆E effect of an amorphous FeNi-based

alloy (Fe40 Ni38 Mo4 B18) Hs saturation

field

Magnetically tunable delay line

Torque Sensors using Amorphous wire

Sixtus tonk효과(large Barkhausen효과)

Hysteresis loops of a Wiegand wire for different reset fields

Curie 온도 및Hopkinson효과

Relation between normalised

saturation polarisation and

normalised Curie temperature

Permeability of a Mn-Zn ferrite as

a function of temperature and field

strength

Conclusions

1) Magnetic sensor 는 자동차 공장자동화 항공우주 및 군사용으로많이 사용되고 있다

2) 새로운 소재개발은 자기센서의 성능개발에 직접적인 영향을 준다2) 새로운 소재개발은 자기센서의 성능개발에 직접적인 영향을 준다

3) 센서의 개발을 위해서는 다양한 전공지식이 요구된다

(물리학 재료공학 기계공학 전자공학)

4) 센서분야가 고부가가치를 창출하는 부품사업이다

5) 핵심부품을 생산하는 중소기업의 item으로도 적절하다

Relative permeability depending on the numbers of ribbon(a)

and the air gap between ribbons

Relative permeability depending on the number of ribbons for the different air gap between ribbons

Relative permeability depending on the total number of ribbons for the different air gap between ribbons

10 pT

100 pT

1 pT

Noise spectrum of the developed search coil magnetometer

BJne

E xH

1minus=

neRH

1minus=

22 nP micromicro minus

Hall 효과

Bt

IRU H

HL =

2

22

)( he

eh

Hpne

nPR

micromicromicromicro

+

minus=

Rectangular Hall plate (cc1cc2 current constant sc1sc2

sensor constant I bias current U voltage drop UH Hall

voltage

Physics carrier concentration and kind of carrier measurement

Engineering magnetic field measurement

Current Measurement

Arrangement for noninvasive

current measurement using an iron

core The current to be measured

produces a proportional magnetic

field which can be measured in the

air gap

Characteristic curve produced by

the current

Arrangement for indirect noninvasive

current measurement using the

compensation principle An iron core as

represented in Figure 3-29 is held field

free by injection a current into a

compensating coil wound on the core

which offsets the field generated by the

current being measured The Hall effect

sensor in the air gap serves as a null

indicator

Circuit diagram for AC-power

measurement using a Hall effect

sensor

DC Power Measurement

Circuit diagram for DC-

power measurement using a

Hall effect sensor

Noncontact Position Sensing

Galvanomagnetic components for sensing the position of permanent magnets

and magnetically conductive materials

Current Sensor Based on Hall Sensor

and Magnetic Core for Hybrid Vehicle

KH Yeon1 SD Kim1 and D Son2 1Auto industry co14F Hanshin IT tower Guro Gu Seoul Korea2Hannam UniversityOjung dong 133 Daejeon Rep of Korea

i

Hall sensor

B

I

SB

ring core

B

I10

g

N

Bl S

micro

)( gtgtrmicro

gab core

Current Sensor Based on Hall

Sensor and Magnetic Core

Hall

Effect

Device

CurrentVoltage

applying for

Hall effect device

operation

Output

signals

Magnetic field

Occurred by

current measurement

Signal

process

circuits

Developed Current Sensor

Magnetic core

Hall sensor

PCB

25

30

35

40

45

50

Output voltage V

Current sensor(Open loop type)

Temp 25C

400A model

+400 ~ -400A

SD 000128

Linearity 003

Linearity of the sensor

Characteristics of the Current Sensors

1000A 10 V power supply

-500 -400 -300 -200 -100 0 100 200 300 400 500

00

05

10

15

20

Output voltage V

current A

Temperature 25Linearity 003

Measuring range -400A ~ +400A

1000A Electronic Load

-3

0

3

6

9

12

15

18

dB

Current sensor

DV2 PCB 24pF

40Aturns

Frequency bandwidth

Gain bandwidth 3 MHz

Current 10 A

Temperature 25

Frequency bandwidth 100 kHz

Sensor output voltage vs frequency

at applied current of 40 Aturns

1 10 100

-18

-15

-12

-9

-6

Frequency kHz 측정온도 25

주파수특성 30kHz 이상(3dB 기준)

측정전류 40Aturns(4A 10턴)

측정주파수 100Hz ~ 100kHz

Temperature 25Current 40Aturns

Frequency range 100 Hz ~ 100 kHz

What is Magnetoresistance

Magnetoresistance effect(AMR)

θθθ 2cos2

12sin12cos(

22 minusminus+∆asymp∆ xxxmx hhhRR

32 minusasymp∆ ρρ New effect GMR CMR and GMI

10 ge∆ ρρ

Two bridge configuration for

rotational angle measurement

measurement angle more than 180o

자동차 Engine Management System

Inductive and Eddy Current

Sensors Excited by Permanent Magnets

tNtU dd)( φsdotminus=

construction of an inductive

sensor (courtesy VDO Adolf sensor (courtesy VDO Adolf

Schindling AG)

1) constant socket

2) terminal package

3) permanent magnet

4) cap

5) soft magnetic core

6) coil

7) plate

8) blade connector

γγ

Sensor with yoke Change in the magnetic flux with

varying air gap Continuous lines

minimum air gap dashed lines

maximum air gap

C-shaped sensor

Sensor with radially

magnetized

permanent magnet

Signal Conditioning

Output voltage U of a DC-excited sensor with permanent

magnets when a single iron object passes by

Schematic electrical diagram of an inductive sensor

Linear Variable Differential Transformer

AC-Excited Sensors for Linear Movement

Principle of construction of an LVDT

Electrical circuit of an LVDT

tIMtNU dd dd sdotminus=sdotminus= φ

tIMtIMUUU dd dd 1212 sdotminussdot=minus=

tIMMU dd)( 12 sdotminus=

)(12 xMMMM =minus=

tIxMU dd)( sdot= tI

UxM

dd)( =

Signal Conditioning

power supply

carrier gen

autoampcontrol

LVDTcarrieramp

demod-ulator

phase

shifter

power supply

carrier gen

passivedemod-ulator

LVDTDCamp

Block diagram of a carrier amplifier system

Block diagram of a DC amplifier system

Variable Inductive Sensors

Principle of construction

of the VLP sensor

Principle of a bridge

circuit

lANL r 20 sdotsdotsdot= micromicro

21 BA UUU minus=

21)i(ii( 211 minus+sdot= LLLUU BA ωωω

)21))()((( minus∆minus+∆+∆+sdot= LLLLLLUU BA

)212)(( minus∆+sdot= LLLUU )212)(( minus∆+sdot= LLLUU BA

LLUU BA 21 ∆sdotsdot=

llLL ∆sdot=∆ d d

llLLUU BA ∆sdotsdot= d d)2(1

Applications and Properties

Principle of a construction of a force transducer

(courtesy Hottinger Baldwin Messtechnik)

Vibrationacceleration sensor

Signal Conditioning

Schematic electrical diagram of a force transducer connected with an

amplifier (courtesy Hottinger Baldwin Messtechnik GmbH)

Variable Gap Sensors

)( FeFe2

0 LLllANL micromicromicro +sdotsdot=

FeFe2

0max lANL sdotsdotsdot= micromicro

Construction of a variable gap sensor

Characteristic of a variable gap sensor

Construction of a differential

cross-anchor sensor

Output voltage U versus core

position x plusmn a limits of the

linear rage

Applications of differential cross-anchor sensors

AC-excited Sensors for Rotary Movements

Principle of construction of a synchro

α cos10 sdotsdot= UKU y

)120-( cos10 degsdotsdot= αUKU z

)240-( cos10 degsdotsdot= αUKU x

)120-( sin3100 degsdotsdotsdot=minus= αKUUUU yxyx

)240-( sin3100 degsdotsdotsdot=minus= αKUUUU zyzy

α sin3100 sdotsdotsdot=minus= KUUUU xzxz

Application to the Torque Sensor

Principle of construction of a torque-type synchro

Torque versus angular

difference

)( sin~ rt αα minussdotKM

)( cos~ rt1r αα minussdotUU

Principle of construction of a control-type sensor

Output voltage versus

angular difference

Principle of construction of a differential sychro

Eddy Current Sensors

tBE dd curl minus=JH = curl

0 div =BH(H)B sdot= micro

E(E)J sdot= σ

A B curl= A B curl=

tdd- A E =

)dd( tAJ minus= σ

tdd curl curl AA σmicro minus=

AA) σωmicro iminus= curl )(curl(1

AA) σωmicro i=∆)((1

Eddy Current Tachometer

Construction of a speedometer (courtesy VDO Adolf Schinding AG) 1) spindle 2) bearing

3) holding spring 4) iron yoke 5) eddy current cup 6) shaft of the magnet 7) support of

the magnet 8) temperature compensation 9) permanent magnet 10) torsion spring

Proximity Sensors

Schematic diagram of a proximity sensor

Output current of a proximity switch versus distance

Inductive Flowmeters

)( Btimessdot= υqF

EqF sdot=BE times=υ

)(ds Btimes== υEU )(ds Btimes== υEU

)( Bd timessdot= υU

Bsdotsdotsdot= υdKU

Development of magnetic phase detection

sensor for steam generator tube

Dirac Son1 Kwan-Sang Ryu2 Duck-Gun Park3

1Hannam University Daejeon Rep of Korea2Korea Research Institute of Standards and Science Daejeon Rep of Korea3KoreaAtomic Energy Research Institute Daejeon Rep of Korea

Introduction

The layout of pressurized water reactor (PWR) components

Primary side Secondary side (non-radioactive side)(radioactive side)

The Structure of SG(Steam Generator)(degradation mechanism)

Secondary SidePrimary Side

SCC

A B

A-B

Steam outlet

Anti-vibration

SCC

Fretting

Wall thinning

IGA

U-bend

In commercial power plants SG- height up to 21 m - weight up to 800 tons - 2~4 sets of SG were installed - SG can contain from 3000 to

16000 tubes each about 20 mmin diameter

Primary coolant outlet Primary coolant inlet

Anti-vibrationbars

Tubesupportplate

Tubesheet

IGA

SCC

Pitting

SCC

Inside Tubesheet

Top of Tubesheet

by SSHwang of KAERI

Denting

Sludge pile

in diameter

The SGT is made of nickel basedInconel alloy which is composed of 75 Ni 165Cr and 815Fe

-Degradation mechanism corrosion pitting denting inter granular attack

-Inspection Eddy current Testing(ECT)

Permeability Variation Clusters (PVC)

(Ferro-magnetic phase)

-005

000

005

010

015

m (emug)

1-1

-002

000

002

004

006

008

m (emug)

1-2

-1000 -500 0 500 1000

-015

-010

-005

H ( Am )

-1000 -500 0 500 1000

-006

-004

-002

H ( Am )

The hystresis loop in the fragment of PVC parts of Kori-1 retired SG tube

-004

-002

000

002

004

006

M (emug)

Inconel 600 tested at RT

under tensile stress

1 2 3

4 5 6

7 8 9-004

-002

000

002

004

006

M(emug)

Inconel 600 Heat treated at

602 oC under tensile stress

1 2 3

How can we detect magnetic phase

(PVC)selectively from the flaws in SGT

-3000 -2000 -1000 0 1000 2000 3000

-006

H (Oe)

7 8 9

10 11 12

-3000 -2000 -1000 0 1000 2000 3000

-006

-004

H(Oe)

4 5 6

7 8 9

The hysteresis loop of the tensile tested specimen at room temperature (a) and tensile tested at high temperature (b)

The magnetic phase can be created under the high temperature andpressure conditions which is correspond to the stress corrosion crackingin the SG tube in the NPP(Bruemmer SM Charlot LA amp Henager CH (1988) Corrosion 782)

Principle of ECT

If we can separate magnetic phase selectively from the

flaws using magnetic sensor the reliability of EC in SGT

inspection will be greatly enhanced

Structure of the permeability

sensor

Dimension and photograph of U-shape

sensing yoke

Design of Magnetic Sensor for PVC

sensor sensing yoke

Photograph of the completed sensor front side (above) and rear side (bottom)

R11R12

R10

R8

R6

R9

R13

R7

R14

C18

1 n

C17

C20

C21

D2

DIODE

SIN COS

-

+

U-2A

4

13

2

-

+

U-2B

75

6

8

-

+

U-3A

13

2

8

+5VC19

104

+5V

Schematic diagram of the sensor system

Electronic Circuit of Magnetic Sensor

R20

R

R21

R

-

+

U5AD797

3

26

74

U6

D1

S12

GND3

+VCC4VCC5

IN6

-VCC7

S28

C41

R13

R26

R18

R25

R2210 Ω

R16

R14

R17

10 k

R15

R27

R32

R28

R33

R29

R34

5 k

R30

C29

C37

104

C32473

C39473C40

104

C33

104

C21

104C23

104

C25

104

C26

104

C30

104

C31

104

C35

104

C36

104

C27

104

C28

104

C34

104

C38

104

D3

DIODE

L1

1

2

L2

1

2

L3

1

2

4

-

+

U-4A

4

13

2

-

+

U-4B

75

6

8

-

+

U-5A

4

13

2

-

+

U-5B

75

6

8

-

+

U-6A

4

13

2

-

+

U-6B

75

6

8

C22

104

-5V

+5V

+5V

+5V

+5V

+5V

+5V

U7

D1

S12

GND3

+VCC4

VCC5

IN6

-VCC7

S28

+5V

-5V

-5V

-5V

-5V

-5V

-5V

-5V

-5V

R19

R24

R

R23

R

C24

OUT(X)

OUT(Y)

R1

20 kR210 k

R3

20 kR410 k

C1

104

C8

104

REF43

OUT(X)

OUT(Y)

REF43

U2

+Vcc1

CH02

CH13

CH24

CH35

COMM6

SHDN7

Vref8

+Vcc9

GND10

GND11

DOUT12BUSY13DIN14CS15

DIN16

-

+

U-1A

13

2

8

-

+

U-1B

4

75

6

C410 uF

C5104

DOUT

C210uF

C6104

C3104

DCLK

C7104

DIN

C10

01uF

CS

BUSY

C14 10uF

J1

CON6

123456

D1

DIODE

R5

47K

C9

10uF

C1310uF

Y1

OSC

OUT3

GND2

VCC4

U3

RSTVPP1

GND10

VCC20

XTAL15

XTAL24

P10AIN012P11AIN113P1214P1315P1416P1517P1618P1719

P30RXD2

P31TXD3

P32INT06

P33INT17

P34T08

P35T19

P3711

U4

C1+1

C1-3

C2+4

C2-5

VCC16

GND15

V+2

V-6

R1OUT12

R2OUT9

T1IN11

T2IN10

R1IN13

R2IN8

T1OUT14

T2OUT7

C12 10uF

C16

01uF

C15 10uF

C11

01uF

-5V

+5V

+5V

+5V

+5V

+5V

+5V

+5V

RST

OSC

OSC

RST

DCLKCSDINBUSYDOUT

U1

IN2

GND

4

OUT6

TEMP3

TRIM5

-5V

+5V

Electronic circuit diagram of the magnetic sensor

Photograph of the completed measuring system data acquisition

software in PC and probe scanning system

Experimental Setup for Magnetic Sensor

Reference material Scanning System Software LabVIEW

Reference Material (1) Normal defects and PVCs

Longitudinal and transverse defects

Def W L D Remarks

1 02 500 0213 (20 ) Inner defects

2 02 500 0427 (40 )

3 02 500 0213 (20 )Outer defectsPVC(1018)4 02 500 0427 (40 )

5 02 500 0639 (60 )

6 02 500 0852 (80 )

7 02 500 0639 (60 ) Inner defects

8 02 500 0852 (80 )

- 1 and 2 are inner defects

- 345 and 6 are outer defects with PVC

- 7 and 8 are inner defects

PVC

PVC

Defect Defect

For longitudinal defects and PVC For circumferential defects and PVC

ECT is very difficult to detect circumferential defects

We can distinguish PVCs and defects and longitudinal and circumferential defects

Flux-gate Magnetometer

One core sensor Two core sensor

3-축 flux-gate Magnetometer의 계략도

Sensorpia Co

pro

cess

or(

AV

R)

Sensor 1

RS422

Interface

Mic

ro-p

roce

ssor(

AV

R)

Sensor 2

Sensor 3

Interface

조립된 마그네토미터의 사진

Sensorpia Co

Analog PCB

Digital PCB

Sensorpia Co선형도(linearity)

10

20

30

40

50

60

y-axis

Magnetometer Output (microT)

-60 -50 -40 -30 -20 -10 0 10 20 30 40 50 60

-60

-50

-40

-30

-20

-10

0

10

Y-axis y=099946 x+0015STD 106E-4

Magnetometer Output (

Applied Magnetic Field (microT)

마그네토미터의 noise 특성 Sensorpia Co

1

10

100

y-axis

Magnetometer noise (nT)

0 1 2 3 4 5 6

1E-4

1E-3

001

01

Magnetometer noise (nT)

Frequency (Hz)

Magnetometer for KoDSAT

-150 -100 -50 0 50 100 150

-15

-10

-5

0

5

10

15

Magnetic Moment (Am

2)

Current (mA)

After Thermal Cycle Test

Measured

Resistance 193 ohm

Photograph of Magnetic torquer

Photograph of KoDSAT

Photograph of

3-axis Fluxgate

Magnetometer

Photograph of Magnetic torquer

Application of magnetometer

Moon magnetic fieldmeasurement

Telescope with direction indication

Joule Effect (Magnetostriction)

ϕ2cosel

l=

∆

0=∆

+∆

+∆

b

b

a

a

l

l

Actuator using Terfenol-D

00

05

10

B (T)

800

1000

1200

1400

1600

Magnetostriction (ppm)

-100 -50 0 50 100

-10

-05

00

B (T)

H (kAm)

2 MPa

4 MPa

6 MPa

8 MPa

10 MPa

12 MPa

-100 -50 0 50 100

-200

0

200

400

600

Magnetostriction (ppm)

H (kAm)

2 MPa

4 MPa

6 MPa

8 MPa

10 MPa

12 MPa

600

700

800

900

1000

-4 -3 -2 -1 0 1 2 3 4

0

10

20

30

40

50

60

Displacement (m

icro meter)

I (A)

FIELD

9 kAm

12 kAm

16 kAm

20 kAm

24 kAm

38 kAm

-50 -40 -30 -20 -10 0 10 20 30 40 50

-100

0

100

200

300

400

500

L (PPM)

H (kAm)

9 kAm

12 kAm

16 kAm

20 kAm

24 kAm

38 kAm

Magnetostrictive displacement sensor

Hysteresis loops under

tensile stress σ

(a) Crystalline 68 NiFe

λs = +25 10-6

(b) crystalline pure Ni λs

= -35 10-6

Villari Effect ( Inverse of Joule Effect)

= -35 10-6

(c) amorphous Co-based

alloy

λs = -35 10-6

ϕσλ 2sin2

3sdotsdot= smeE

γ

Permeability depending on the stress

σλmicromicro

1

3

2

Y

J

so

s

r =

γ

Calculated magnetization curves under stress

Variation of magnetization curve by an applied

tensile force (Co-based amorphous alloy)

Alloy Requirement

Materials for magnetoelastic sensors

Why amorphous magnetic materials are important

Stress-strain curves of several materials

Coercivity and hardness of several materials

Principles of magnetoelastic sensors

Non-contact torque sensor

Principle of cross torductor torque

sensor and flux pattern of sensor

poles on the surface of a shaft

a) without and b)with torsional load

Equivalent magnetic circuit of

cross type torque sensor

Helices of principal tensile and compressive stress on the surface of

a shaft subjected to torsion [32] Correlated changes of permeability

are detected by four-branch yoke system with sensing coils 123

and 4 and a common excitation pole

Examples of torque sensors

Four-branch type torque sensor

heads Pole structures realized

by commercial multi-pole

ferrites 14 and 18 min in

diameter (diameter of sensor

h e a d 1 7 a n d 2 4 m m

respectively) respectively)

Principle of Ring Torductor torque transducer

(a b) Physical structure (c) evolution of the

shaft surface under the transducer poles A and BRing torductor for measuring

torque on ship propeller shafts

(shaft diameter ca 500 mm)

(Courtesy ASEA Brown

Boveri AG)

Principal designs of coaxial torque sensors

Schematic diagram of data processing

electronics of a torque sensor

Extensometer (a) Construction of strain sensing element using

amorphous ribbon wound core (b) configuration of lumped

windings

∆E effect of an amorphous FeNi-based

alloy (Fe40 Ni38 Mo4 B18) Hs saturation

field

Magnetically tunable delay line

Torque Sensors using Amorphous wire

Sixtus tonk효과(large Barkhausen효과)

Hysteresis loops of a Wiegand wire for different reset fields

Curie 온도 및Hopkinson효과

Relation between normalised

saturation polarisation and

normalised Curie temperature

Permeability of a Mn-Zn ferrite as

a function of temperature and field

strength

Conclusions

1) Magnetic sensor 는 자동차 공장자동화 항공우주 및 군사용으로많이 사용되고 있다

2) 새로운 소재개발은 자기센서의 성능개발에 직접적인 영향을 준다2) 새로운 소재개발은 자기센서의 성능개발에 직접적인 영향을 준다

3) 센서의 개발을 위해서는 다양한 전공지식이 요구된다

(물리학 재료공학 기계공학 전자공학)

4) 센서분야가 고부가가치를 창출하는 부품사업이다

5) 핵심부품을 생산하는 중소기업의 item으로도 적절하다

Relative permeability depending on the number of ribbons for the different air gap between ribbons

Relative permeability depending on the total number of ribbons for the different air gap between ribbons

10 pT

100 pT

1 pT

Noise spectrum of the developed search coil magnetometer

BJne

E xH

1minus=

neRH

1minus=

22 nP micromicro minus

Hall 효과

Bt

IRU H

HL =

2

22

)( he

eh

Hpne

nPR

micromicromicromicro

+

minus=

Rectangular Hall plate (cc1cc2 current constant sc1sc2

sensor constant I bias current U voltage drop UH Hall

voltage

Physics carrier concentration and kind of carrier measurement

Engineering magnetic field measurement

Current Measurement

Arrangement for noninvasive

current measurement using an iron

core The current to be measured

produces a proportional magnetic

field which can be measured in the

air gap

Characteristic curve produced by

the current

Arrangement for indirect noninvasive

current measurement using the

compensation principle An iron core as

represented in Figure 3-29 is held field

free by injection a current into a

compensating coil wound on the core

which offsets the field generated by the

current being measured The Hall effect

sensor in the air gap serves as a null

indicator

Circuit diagram for AC-power

measurement using a Hall effect

sensor

DC Power Measurement

Circuit diagram for DC-

power measurement using a

Hall effect sensor

Noncontact Position Sensing

Galvanomagnetic components for sensing the position of permanent magnets

and magnetically conductive materials

Current Sensor Based on Hall Sensor

and Magnetic Core for Hybrid Vehicle

KH Yeon1 SD Kim1 and D Son2 1Auto industry co14F Hanshin IT tower Guro Gu Seoul Korea2Hannam UniversityOjung dong 133 Daejeon Rep of Korea

i

Hall sensor

B

I

SB

ring core

B

I10

g

N

Bl S

micro

)( gtgtrmicro

gab core

Current Sensor Based on Hall

Sensor and Magnetic Core

Hall

Effect

Device

CurrentVoltage

applying for

Hall effect device

operation

Output

signals

Magnetic field

Occurred by

current measurement

Signal

process

circuits

Developed Current Sensor

Magnetic core

Hall sensor

PCB

25

30

35

40

45

50

Output voltage V

Current sensor(Open loop type)

Temp 25C

400A model

+400 ~ -400A

SD 000128

Linearity 003

Linearity of the sensor

Characteristics of the Current Sensors

1000A 10 V power supply

-500 -400 -300 -200 -100 0 100 200 300 400 500

00

05

10

15

20

Output voltage V

current A

Temperature 25Linearity 003

Measuring range -400A ~ +400A

1000A Electronic Load

-3

0

3

6

9

12

15

18

dB

Current sensor

DV2 PCB 24pF

40Aturns

Frequency bandwidth

Gain bandwidth 3 MHz

Current 10 A

Temperature 25

Frequency bandwidth 100 kHz

Sensor output voltage vs frequency

at applied current of 40 Aturns

1 10 100

-18

-15

-12

-9

-6

Frequency kHz 측정온도 25

주파수특성 30kHz 이상(3dB 기준)

측정전류 40Aturns(4A 10턴)

측정주파수 100Hz ~ 100kHz

Temperature 25Current 40Aturns

Frequency range 100 Hz ~ 100 kHz

What is Magnetoresistance

Magnetoresistance effect(AMR)

θθθ 2cos2

12sin12cos(

22 minusminus+∆asymp∆ xxxmx hhhRR

32 minusasymp∆ ρρ New effect GMR CMR and GMI

10 ge∆ ρρ

Two bridge configuration for

rotational angle measurement

measurement angle more than 180o

자동차 Engine Management System

Inductive and Eddy Current

Sensors Excited by Permanent Magnets

tNtU dd)( φsdotminus=

construction of an inductive

sensor (courtesy VDO Adolf sensor (courtesy VDO Adolf

Schindling AG)

1) constant socket

2) terminal package

3) permanent magnet

4) cap

5) soft magnetic core

6) coil

7) plate

8) blade connector

γγ

Sensor with yoke Change in the magnetic flux with

varying air gap Continuous lines

minimum air gap dashed lines

maximum air gap

C-shaped sensor

Sensor with radially

magnetized

permanent magnet

Signal Conditioning

Output voltage U of a DC-excited sensor with permanent

magnets when a single iron object passes by

Schematic electrical diagram of an inductive sensor

Linear Variable Differential Transformer

AC-Excited Sensors for Linear Movement

Principle of construction of an LVDT

Electrical circuit of an LVDT

tIMtNU dd dd sdotminus=sdotminus= φ

tIMtIMUUU dd dd 1212 sdotminussdot=minus=

tIMMU dd)( 12 sdotminus=

)(12 xMMMM =minus=

tIxMU dd)( sdot= tI

UxM

dd)( =

Signal Conditioning

power supply

carrier gen

autoampcontrol

LVDTcarrieramp

demod-ulator

phase

shifter

power supply

carrier gen

passivedemod-ulator

LVDTDCamp

Block diagram of a carrier amplifier system

Block diagram of a DC amplifier system

Variable Inductive Sensors

Principle of construction

of the VLP sensor

Principle of a bridge

circuit

lANL r 20 sdotsdotsdot= micromicro

21 BA UUU minus=

21)i(ii( 211 minus+sdot= LLLUU BA ωωω

)21))()((( minus∆minus+∆+∆+sdot= LLLLLLUU BA

)212)(( minus∆+sdot= LLLUU )212)(( minus∆+sdot= LLLUU BA

LLUU BA 21 ∆sdotsdot=

llLL ∆sdot=∆ d d

llLLUU BA ∆sdotsdot= d d)2(1

Applications and Properties

Principle of a construction of a force transducer

(courtesy Hottinger Baldwin Messtechnik)

Vibrationacceleration sensor

Signal Conditioning

Schematic electrical diagram of a force transducer connected with an

amplifier (courtesy Hottinger Baldwin Messtechnik GmbH)

Variable Gap Sensors

)( FeFe2

0 LLllANL micromicromicro +sdotsdot=

FeFe2

0max lANL sdotsdotsdot= micromicro

Construction of a variable gap sensor

Characteristic of a variable gap sensor

Construction of a differential

cross-anchor sensor

Output voltage U versus core

position x plusmn a limits of the

linear rage

Applications of differential cross-anchor sensors

AC-excited Sensors for Rotary Movements

Principle of construction of a synchro

α cos10 sdotsdot= UKU y

)120-( cos10 degsdotsdot= αUKU z

)240-( cos10 degsdotsdot= αUKU x

)120-( sin3100 degsdotsdotsdot=minus= αKUUUU yxyx

)240-( sin3100 degsdotsdotsdot=minus= αKUUUU zyzy

α sin3100 sdotsdotsdot=minus= KUUUU xzxz

Application to the Torque Sensor

Principle of construction of a torque-type synchro

Torque versus angular

difference

)( sin~ rt αα minussdotKM

)( cos~ rt1r αα minussdotUU

Principle of construction of a control-type sensor

Output voltage versus

angular difference

Principle of construction of a differential sychro

Eddy Current Sensors

tBE dd curl minus=JH = curl

0 div =BH(H)B sdot= micro

E(E)J sdot= σ

A B curl= A B curl=

tdd- A E =

)dd( tAJ minus= σ

tdd curl curl AA σmicro minus=

AA) σωmicro iminus= curl )(curl(1

AA) σωmicro i=∆)((1

Eddy Current Tachometer

Construction of a speedometer (courtesy VDO Adolf Schinding AG) 1) spindle 2) bearing

3) holding spring 4) iron yoke 5) eddy current cup 6) shaft of the magnet 7) support of

the magnet 8) temperature compensation 9) permanent magnet 10) torsion spring

Proximity Sensors

Schematic diagram of a proximity sensor

Output current of a proximity switch versus distance

Inductive Flowmeters

)( Btimessdot= υqF

EqF sdot=BE times=υ

)(ds Btimes== υEU )(ds Btimes== υEU

)( Bd timessdot= υU

Bsdotsdotsdot= υdKU

Development of magnetic phase detection

sensor for steam generator tube

Dirac Son1 Kwan-Sang Ryu2 Duck-Gun Park3

1Hannam University Daejeon Rep of Korea2Korea Research Institute of Standards and Science Daejeon Rep of Korea3KoreaAtomic Energy Research Institute Daejeon Rep of Korea

Introduction

The layout of pressurized water reactor (PWR) components

Primary side Secondary side (non-radioactive side)(radioactive side)

The Structure of SG(Steam Generator)(degradation mechanism)

Secondary SidePrimary Side

SCC

A B

A-B

Steam outlet

Anti-vibration

SCC

Fretting

Wall thinning

IGA

U-bend

In commercial power plants SG- height up to 21 m - weight up to 800 tons - 2~4 sets of SG were installed - SG can contain from 3000 to

16000 tubes each about 20 mmin diameter

Primary coolant outlet Primary coolant inlet

Anti-vibrationbars

Tubesupportplate

Tubesheet

IGA

SCC

Pitting

SCC

Inside Tubesheet

Top of Tubesheet

by SSHwang of KAERI

Denting

Sludge pile

in diameter

The SGT is made of nickel basedInconel alloy which is composed of 75 Ni 165Cr and 815Fe

-Degradation mechanism corrosion pitting denting inter granular attack

-Inspection Eddy current Testing(ECT)

Permeability Variation Clusters (PVC)

(Ferro-magnetic phase)

-005

000

005

010

015

m (emug)

1-1

-002

000

002

004

006

008

m (emug)

1-2

-1000 -500 0 500 1000

-015

-010

-005

H ( Am )

-1000 -500 0 500 1000

-006

-004

-002

H ( Am )

The hystresis loop in the fragment of PVC parts of Kori-1 retired SG tube

-004

-002

000

002

004

006

M (emug)

Inconel 600 tested at RT

under tensile stress

1 2 3

4 5 6

7 8 9-004

-002

000

002

004

006

M(emug)

Inconel 600 Heat treated at

602 oC under tensile stress

1 2 3

How can we detect magnetic phase

(PVC)selectively from the flaws in SGT

-3000 -2000 -1000 0 1000 2000 3000

-006

H (Oe)

7 8 9

10 11 12

-3000 -2000 -1000 0 1000 2000 3000

-006

-004

H(Oe)

4 5 6

7 8 9

The hysteresis loop of the tensile tested specimen at room temperature (a) and tensile tested at high temperature (b)

The magnetic phase can be created under the high temperature andpressure conditions which is correspond to the stress corrosion crackingin the SG tube in the NPP(Bruemmer SM Charlot LA amp Henager CH (1988) Corrosion 782)

Principle of ECT

If we can separate magnetic phase selectively from the

flaws using magnetic sensor the reliability of EC in SGT

inspection will be greatly enhanced

Structure of the permeability

sensor

Dimension and photograph of U-shape

sensing yoke

Design of Magnetic Sensor for PVC

sensor sensing yoke

Photograph of the completed sensor front side (above) and rear side (bottom)

R11R12

R10

R8

R6

R9

R13

R7

R14

C18

1 n

C17

C20

C21

D2

DIODE

SIN COS

-

+

U-2A

4

13

2

-

+

U-2B

75

6

8

-

+

U-3A

13

2

8

+5VC19

104

+5V

Schematic diagram of the sensor system

Electronic Circuit of Magnetic Sensor

R20

R

R21

R

-

+

U5AD797

3

26

74

U6

D1

S12

GND3

+VCC4VCC5

IN6

-VCC7

S28

C41

R13

R26

R18

R25

R2210 Ω

R16

R14

R17

10 k

R15

R27

R32

R28

R33

R29

R34

5 k

R30

C29

C37

104

C32473

C39473C40

104

C33

104

C21

104C23

104

C25

104

C26

104

C30

104

C31

104

C35

104

C36

104

C27

104

C28

104

C34

104

C38

104

D3

DIODE

L1

1

2

L2

1

2

L3

1

2

4

-

+

U-4A

4

13

2

-

+

U-4B

75

6

8

-

+

U-5A

4

13

2

-

+

U-5B

75

6

8

-

+

U-6A

4

13

2

-

+

U-6B

75

6

8

C22

104

-5V

+5V

+5V

+5V

+5V

+5V

+5V

U7

D1

S12

GND3

+VCC4

VCC5

IN6

-VCC7

S28

+5V

-5V

-5V

-5V

-5V

-5V

-5V

-5V

-5V

R19

R24

R

R23

R

C24

OUT(X)

OUT(Y)

R1

20 kR210 k

R3

20 kR410 k

C1

104

C8

104

REF43

OUT(X)

OUT(Y)

REF43

U2

+Vcc1

CH02

CH13

CH24

CH35

COMM6

SHDN7

Vref8

+Vcc9

GND10

GND11

DOUT12BUSY13DIN14CS15

DIN16

-

+

U-1A

13

2

8

-

+

U-1B

4

75

6

C410 uF

C5104

DOUT

C210uF

C6104

C3104

DCLK

C7104

DIN

C10

01uF

CS

BUSY

C14 10uF

J1

CON6

123456

D1

DIODE

R5

47K

C9

10uF

C1310uF

Y1

OSC

OUT3

GND2

VCC4

U3

RSTVPP1

GND10

VCC20

XTAL15

XTAL24

P10AIN012P11AIN113P1214P1315P1416P1517P1618P1719

P30RXD2

P31TXD3

P32INT06

P33INT17

P34T08

P35T19

P3711

U4

C1+1

C1-3

C2+4

C2-5

VCC16

GND15

V+2

V-6

R1OUT12

R2OUT9

T1IN11

T2IN10

R1IN13

R2IN8

T1OUT14

T2OUT7

C12 10uF

C16

01uF

C15 10uF

C11

01uF

-5V

+5V

+5V

+5V

+5V

+5V

+5V

+5V

RST

OSC

OSC

RST

DCLKCSDINBUSYDOUT

U1

IN2

GND

4

OUT6

TEMP3

TRIM5

-5V

+5V

Electronic circuit diagram of the magnetic sensor

Photograph of the completed measuring system data acquisition

software in PC and probe scanning system

Experimental Setup for Magnetic Sensor

Reference material Scanning System Software LabVIEW

Reference Material (1) Normal defects and PVCs

Longitudinal and transverse defects

Def W L D Remarks

1 02 500 0213 (20 ) Inner defects

2 02 500 0427 (40 )

3 02 500 0213 (20 )Outer defectsPVC(1018)4 02 500 0427 (40 )

5 02 500 0639 (60 )

6 02 500 0852 (80 )

7 02 500 0639 (60 ) Inner defects

8 02 500 0852 (80 )

- 1 and 2 are inner defects

- 345 and 6 are outer defects with PVC

- 7 and 8 are inner defects

PVC

PVC

Defect Defect

For longitudinal defects and PVC For circumferential defects and PVC

ECT is very difficult to detect circumferential defects

We can distinguish PVCs and defects and longitudinal and circumferential defects

Flux-gate Magnetometer

One core sensor Two core sensor

3-축 flux-gate Magnetometer의 계략도

Sensorpia Co

pro

cess

or(

AV

R)

Sensor 1

RS422

Interface

Mic

ro-p

roce

ssor(

AV

R)

Sensor 2

Sensor 3

Interface

조립된 마그네토미터의 사진

Sensorpia Co

Analog PCB

Digital PCB

Sensorpia Co선형도(linearity)

10

20

30

40

50

60

y-axis

Magnetometer Output (microT)

-60 -50 -40 -30 -20 -10 0 10 20 30 40 50 60

-60

-50

-40

-30

-20

-10

0

10

Y-axis y=099946 x+0015STD 106E-4

Magnetometer Output (

Applied Magnetic Field (microT)

마그네토미터의 noise 특성 Sensorpia Co

1

10

100

y-axis

Magnetometer noise (nT)

0 1 2 3 4 5 6

1E-4

1E-3

001

01

Magnetometer noise (nT)

Frequency (Hz)

Magnetometer for KoDSAT

-150 -100 -50 0 50 100 150

-15

-10

-5

0

5

10

15

Magnetic Moment (Am

2)

Current (mA)

After Thermal Cycle Test

Measured

Resistance 193 ohm

Photograph of Magnetic torquer

Photograph of KoDSAT

Photograph of

3-axis Fluxgate

Magnetometer

Photograph of Magnetic torquer

Application of magnetometer

Moon magnetic fieldmeasurement

Telescope with direction indication

Joule Effect (Magnetostriction)

ϕ2cosel

l=

∆

0=∆

+∆

+∆

b

b

a

a

l

l

Actuator using Terfenol-D

00

05

10

B (T)

800

1000

1200

1400

1600

Magnetostriction (ppm)

-100 -50 0 50 100

-10

-05

00

B (T)

H (kAm)

2 MPa

4 MPa

6 MPa

8 MPa

10 MPa

12 MPa

-100 -50 0 50 100

-200

0

200

400

600

Magnetostriction (ppm)

H (kAm)

2 MPa

4 MPa

6 MPa

8 MPa

10 MPa

12 MPa

600

700

800

900

1000

-4 -3 -2 -1 0 1 2 3 4

0

10

20

30

40

50

60

Displacement (m

icro meter)

I (A)

FIELD

9 kAm

12 kAm

16 kAm

20 kAm

24 kAm

38 kAm

-50 -40 -30 -20 -10 0 10 20 30 40 50

-100

0

100

200

300

400

500

L (PPM)

H (kAm)

9 kAm

12 kAm

16 kAm

20 kAm

24 kAm

38 kAm

Magnetostrictive displacement sensor

Hysteresis loops under

tensile stress σ

(a) Crystalline 68 NiFe

λs = +25 10-6

(b) crystalline pure Ni λs

= -35 10-6

Villari Effect ( Inverse of Joule Effect)

= -35 10-6

(c) amorphous Co-based

alloy

λs = -35 10-6

ϕσλ 2sin2

3sdotsdot= smeE

γ

Permeability depending on the stress

σλmicromicro

1

3

2

Y

J

so

s

r =

γ

Calculated magnetization curves under stress

Variation of magnetization curve by an applied

tensile force (Co-based amorphous alloy)

Alloy Requirement

Materials for magnetoelastic sensors

Why amorphous magnetic materials are important

Stress-strain curves of several materials

Coercivity and hardness of several materials

Principles of magnetoelastic sensors

Non-contact torque sensor

Principle of cross torductor torque

sensor and flux pattern of sensor

poles on the surface of a shaft

a) without and b)with torsional load

Equivalent magnetic circuit of

cross type torque sensor

Helices of principal tensile and compressive stress on the surface of

a shaft subjected to torsion [32] Correlated changes of permeability

are detected by four-branch yoke system with sensing coils 123

and 4 and a common excitation pole

Examples of torque sensors

Four-branch type torque sensor

heads Pole structures realized

by commercial multi-pole

ferrites 14 and 18 min in

diameter (diameter of sensor

h e a d 1 7 a n d 2 4 m m

respectively) respectively)

Principle of Ring Torductor torque transducer

(a b) Physical structure (c) evolution of the

shaft surface under the transducer poles A and BRing torductor for measuring

torque on ship propeller shafts

(shaft diameter ca 500 mm)

(Courtesy ASEA Brown

Boveri AG)

Principal designs of coaxial torque sensors

Schematic diagram of data processing

electronics of a torque sensor

Extensometer (a) Construction of strain sensing element using

amorphous ribbon wound core (b) configuration of lumped

windings

∆E effect of an amorphous FeNi-based

alloy (Fe40 Ni38 Mo4 B18) Hs saturation

field

Magnetically tunable delay line

Torque Sensors using Amorphous wire

Sixtus tonk효과(large Barkhausen효과)

Hysteresis loops of a Wiegand wire for different reset fields

Curie 온도 및Hopkinson효과

Relation between normalised

saturation polarisation and

normalised Curie temperature

Permeability of a Mn-Zn ferrite as

a function of temperature and field

strength

Conclusions

1) Magnetic sensor 는 자동차 공장자동화 항공우주 및 군사용으로많이 사용되고 있다

2) 새로운 소재개발은 자기센서의 성능개발에 직접적인 영향을 준다2) 새로운 소재개발은 자기센서의 성능개발에 직접적인 영향을 준다

3) 센서의 개발을 위해서는 다양한 전공지식이 요구된다

(물리학 재료공학 기계공학 전자공학)

4) 센서분야가 고부가가치를 창출하는 부품사업이다

5) 핵심부품을 생산하는 중소기업의 item으로도 적절하다

Relative permeability depending on the total number of ribbons for the different air gap between ribbons

10 pT

100 pT

1 pT

Noise spectrum of the developed search coil magnetometer

BJne

E xH

1minus=

neRH

1minus=

22 nP micromicro minus

Hall 효과

Bt

IRU H

HL =

2

22

)( he

eh

Hpne

nPR

micromicromicromicro

+

minus=

Rectangular Hall plate (cc1cc2 current constant sc1sc2

sensor constant I bias current U voltage drop UH Hall

voltage

Physics carrier concentration and kind of carrier measurement

Engineering magnetic field measurement

Current Measurement

Arrangement for noninvasive

current measurement using an iron

core The current to be measured

produces a proportional magnetic

field which can be measured in the

air gap

Characteristic curve produced by

the current

Arrangement for indirect noninvasive

current measurement using the

compensation principle An iron core as

represented in Figure 3-29 is held field

free by injection a current into a

compensating coil wound on the core

which offsets the field generated by the

current being measured The Hall effect

sensor in the air gap serves as a null

indicator

Circuit diagram for AC-power

measurement using a Hall effect

sensor

DC Power Measurement

Circuit diagram for DC-

power measurement using a

Hall effect sensor

Noncontact Position Sensing

Galvanomagnetic components for sensing the position of permanent magnets

and magnetically conductive materials

Current Sensor Based on Hall Sensor

and Magnetic Core for Hybrid Vehicle

KH Yeon1 SD Kim1 and D Son2 1Auto industry co14F Hanshin IT tower Guro Gu Seoul Korea2Hannam UniversityOjung dong 133 Daejeon Rep of Korea

i

Hall sensor

B

I

SB

ring core

B

I10

g

N

Bl S

micro

)( gtgtrmicro

gab core

Current Sensor Based on Hall

Sensor and Magnetic Core

Hall

Effect

Device

CurrentVoltage

applying for

Hall effect device

operation

Output

signals

Magnetic field

Occurred by

current measurement

Signal

process

circuits

Developed Current Sensor

Magnetic core

Hall sensor

PCB

25

30

35

40

45

50

Output voltage V

Current sensor(Open loop type)

Temp 25C

400A model

+400 ~ -400A

SD 000128

Linearity 003

Linearity of the sensor

Characteristics of the Current Sensors

1000A 10 V power supply

-500 -400 -300 -200 -100 0 100 200 300 400 500

00

05

10

15

20

Output voltage V

current A

Temperature 25Linearity 003

Measuring range -400A ~ +400A

1000A Electronic Load

-3

0

3

6

9

12

15

18

dB

Current sensor

DV2 PCB 24pF

40Aturns

Frequency bandwidth

Gain bandwidth 3 MHz

Current 10 A

Temperature 25

Frequency bandwidth 100 kHz

Sensor output voltage vs frequency

at applied current of 40 Aturns

1 10 100

-18

-15

-12

-9

-6

Frequency kHz 측정온도 25

주파수특성 30kHz 이상(3dB 기준)

측정전류 40Aturns(4A 10턴)

측정주파수 100Hz ~ 100kHz

Temperature 25Current 40Aturns

Frequency range 100 Hz ~ 100 kHz

What is Magnetoresistance

Magnetoresistance effect(AMR)

θθθ 2cos2

12sin12cos(

22 minusminus+∆asymp∆ xxxmx hhhRR

32 minusasymp∆ ρρ New effect GMR CMR and GMI

10 ge∆ ρρ

Two bridge configuration for

rotational angle measurement

measurement angle more than 180o

자동차 Engine Management System

Inductive and Eddy Current

Sensors Excited by Permanent Magnets

tNtU dd)( φsdotminus=

construction of an inductive

sensor (courtesy VDO Adolf sensor (courtesy VDO Adolf

Schindling AG)

1) constant socket

2) terminal package

3) permanent magnet

4) cap

5) soft magnetic core

6) coil

7) plate

8) blade connector

γγ

Sensor with yoke Change in the magnetic flux with

varying air gap Continuous lines

minimum air gap dashed lines

maximum air gap

C-shaped sensor

Sensor with radially

magnetized

permanent magnet

Signal Conditioning

Output voltage U of a DC-excited sensor with permanent

magnets when a single iron object passes by

Schematic electrical diagram of an inductive sensor

Linear Variable Differential Transformer

AC-Excited Sensors for Linear Movement

Principle of construction of an LVDT

Electrical circuit of an LVDT

tIMtNU dd dd sdotminus=sdotminus= φ

tIMtIMUUU dd dd 1212 sdotminussdot=minus=

tIMMU dd)( 12 sdotminus=

)(12 xMMMM =minus=

tIxMU dd)( sdot= tI

UxM

dd)( =

Signal Conditioning

power supply

carrier gen

autoampcontrol

LVDTcarrieramp

demod-ulator

phase

shifter

power supply

carrier gen

passivedemod-ulator

LVDTDCamp

Block diagram of a carrier amplifier system

Block diagram of a DC amplifier system

Variable Inductive Sensors

Principle of construction

of the VLP sensor

Principle of a bridge

circuit

lANL r 20 sdotsdotsdot= micromicro

21 BA UUU minus=

21)i(ii( 211 minus+sdot= LLLUU BA ωωω

)21))()((( minus∆minus+∆+∆+sdot= LLLLLLUU BA

)212)(( minus∆+sdot= LLLUU )212)(( minus∆+sdot= LLLUU BA

LLUU BA 21 ∆sdotsdot=

llLL ∆sdot=∆ d d

llLLUU BA ∆sdotsdot= d d)2(1

Applications and Properties

Principle of a construction of a force transducer

(courtesy Hottinger Baldwin Messtechnik)

Vibrationacceleration sensor

Signal Conditioning

Schematic electrical diagram of a force transducer connected with an

amplifier (courtesy Hottinger Baldwin Messtechnik GmbH)

Variable Gap Sensors

)( FeFe2

0 LLllANL micromicromicro +sdotsdot=

FeFe2

0max lANL sdotsdotsdot= micromicro

Construction of a variable gap sensor

Characteristic of a variable gap sensor

Construction of a differential

cross-anchor sensor

Output voltage U versus core

position x plusmn a limits of the

linear rage

Applications of differential cross-anchor sensors

AC-excited Sensors for Rotary Movements

Principle of construction of a synchro

α cos10 sdotsdot= UKU y

)120-( cos10 degsdotsdot= αUKU z

)240-( cos10 degsdotsdot= αUKU x

)120-( sin3100 degsdotsdotsdot=minus= αKUUUU yxyx

)240-( sin3100 degsdotsdotsdot=minus= αKUUUU zyzy

α sin3100 sdotsdotsdot=minus= KUUUU xzxz

Application to the Torque Sensor

Principle of construction of a torque-type synchro

Torque versus angular

difference

)( sin~ rt αα minussdotKM

)( cos~ rt1r αα minussdotUU

Principle of construction of a control-type sensor

Output voltage versus

angular difference

Principle of construction of a differential sychro

Eddy Current Sensors

tBE dd curl minus=JH = curl

0 div =BH(H)B sdot= micro

E(E)J sdot= σ

A B curl= A B curl=

tdd- A E =

)dd( tAJ minus= σ

tdd curl curl AA σmicro minus=

AA) σωmicro iminus= curl )(curl(1

AA) σωmicro i=∆)((1

Eddy Current Tachometer

Construction of a speedometer (courtesy VDO Adolf Schinding AG) 1) spindle 2) bearing

3) holding spring 4) iron yoke 5) eddy current cup 6) shaft of the magnet 7) support of

the magnet 8) temperature compensation 9) permanent magnet 10) torsion spring

Proximity Sensors

Schematic diagram of a proximity sensor

Output current of a proximity switch versus distance

Inductive Flowmeters

)( Btimessdot= υqF

EqF sdot=BE times=υ

)(ds Btimes== υEU )(ds Btimes== υEU

)( Bd timessdot= υU

Bsdotsdotsdot= υdKU

Development of magnetic phase detection

sensor for steam generator tube

Dirac Son1 Kwan-Sang Ryu2 Duck-Gun Park3

1Hannam University Daejeon Rep of Korea2Korea Research Institute of Standards and Science Daejeon Rep of Korea3KoreaAtomic Energy Research Institute Daejeon Rep of Korea

Introduction

The layout of pressurized water reactor (PWR) components

Primary side Secondary side (non-radioactive side)(radioactive side)

The Structure of SG(Steam Generator)(degradation mechanism)

Secondary SidePrimary Side

SCC

A B

A-B

Steam outlet

Anti-vibration

SCC

Fretting

Wall thinning

IGA

U-bend

In commercial power plants SG- height up to 21 m - weight up to 800 tons - 2~4 sets of SG were installed - SG can contain from 3000 to

16000 tubes each about 20 mmin diameter

Primary coolant outlet Primary coolant inlet

Anti-vibrationbars

Tubesupportplate

Tubesheet

IGA

SCC

Pitting

SCC

Inside Tubesheet

Top of Tubesheet

by SSHwang of KAERI

Denting

Sludge pile

in diameter

The SGT is made of nickel basedInconel alloy which is composed of 75 Ni 165Cr and 815Fe

-Degradation mechanism corrosion pitting denting inter granular attack

-Inspection Eddy current Testing(ECT)

Permeability Variation Clusters (PVC)

(Ferro-magnetic phase)

-005

000

005

010

015

m (emug)

1-1

-002

000

002

004

006

008

m (emug)

1-2

-1000 -500 0 500 1000

-015

-010

-005

H ( Am )

-1000 -500 0 500 1000

-006

-004

-002

H ( Am )

The hystresis loop in the fragment of PVC parts of Kori-1 retired SG tube

-004

-002

000

002

004

006

M (emug)

Inconel 600 tested at RT

under tensile stress

1 2 3

4 5 6

7 8 9-004

-002

000

002

004

006

M(emug)

Inconel 600 Heat treated at

602 oC under tensile stress

1 2 3

How can we detect magnetic phase

(PVC)selectively from the flaws in SGT

-3000 -2000 -1000 0 1000 2000 3000

-006

H (Oe)

7 8 9

10 11 12

-3000 -2000 -1000 0 1000 2000 3000

-006

-004

H(Oe)

4 5 6

7 8 9

The hysteresis loop of the tensile tested specimen at room temperature (a) and tensile tested at high temperature (b)

The magnetic phase can be created under the high temperature andpressure conditions which is correspond to the stress corrosion crackingin the SG tube in the NPP(Bruemmer SM Charlot LA amp Henager CH (1988) Corrosion 782)

Principle of ECT

If we can separate magnetic phase selectively from the

flaws using magnetic sensor the reliability of EC in SGT

inspection will be greatly enhanced

Structure of the permeability

sensor

Dimension and photograph of U-shape

sensing yoke

Design of Magnetic Sensor for PVC

sensor sensing yoke

Photograph of the completed sensor front side (above) and rear side (bottom)

R11R12

R10

R8

R6

R9

R13

R7

R14

C18

1 n

C17

C20

C21

D2

DIODE

SIN COS

-

+

U-2A

4

13

2

-

+

U-2B

75

6

8

-

+

U-3A

13

2

8

+5VC19

104

+5V

Schematic diagram of the sensor system

Electronic Circuit of Magnetic Sensor

R20

R

R21

R

-

+

U5AD797

3

26

74

U6

D1

S12

GND3

+VCC4VCC5

IN6

-VCC7

S28

C41

R13

R26

R18

R25

R2210 Ω

R16

R14

R17

10 k

R15

R27

R32

R28

R33

R29

R34

5 k

R30

C29

C37

104

C32473

C39473C40

104

C33

104

C21

104C23

104

C25

104

C26

104

C30

104

C31

104

C35

104

C36

104

C27

104

C28

104

C34

104

C38

104

D3

DIODE

L1

1

2

L2

1

2

L3

1

2

4

-

+

U-4A

4

13

2

-

+

U-4B

75

6

8

-

+

U-5A

4

13

2

-

+

U-5B

75

6

8

-

+

U-6A

4

13

2

-

+

U-6B

75

6

8

C22

104

-5V

+5V

+5V

+5V

+5V

+5V

+5V

U7

D1

S12

GND3

+VCC4

VCC5

IN6

-VCC7

S28

+5V

-5V

-5V

-5V

-5V

-5V

-5V

-5V

-5V

R19

R24

R

R23

R

C24

OUT(X)

OUT(Y)

R1

20 kR210 k

R3

20 kR410 k

C1

104

C8

104

REF43

OUT(X)

OUT(Y)

REF43

U2

+Vcc1

CH02

CH13

CH24

CH35

COMM6

SHDN7

Vref8

+Vcc9

GND10

GND11

DOUT12BUSY13DIN14CS15

DIN16

-

+

U-1A

13

2

8

-

+

U-1B

4

75

6

C410 uF

C5104

DOUT

C210uF

C6104

C3104

DCLK

C7104

DIN

C10

01uF

CS

BUSY

C14 10uF

J1

CON6

123456

D1

DIODE

R5

47K

C9

10uF

C1310uF

Y1

OSC

OUT3

GND2

VCC4

U3

RSTVPP1

GND10

VCC20

XTAL15

XTAL24

P10AIN012P11AIN113P1214P1315P1416P1517P1618P1719

P30RXD2

P31TXD3

P32INT06

P33INT17

P34T08

P35T19

P3711

U4

C1+1

C1-3

C2+4

C2-5

VCC16

GND15

V+2

V-6

R1OUT12

R2OUT9

T1IN11

T2IN10

R1IN13

R2IN8

T1OUT14

T2OUT7

C12 10uF

C16

01uF

C15 10uF

C11

01uF

-5V

+5V

+5V

+5V

+5V

+5V

+5V

+5V

RST

OSC

OSC

RST

DCLKCSDINBUSYDOUT

U1

IN2

GND

4

OUT6

TEMP3

TRIM5

-5V

+5V

Electronic circuit diagram of the magnetic sensor

Photograph of the completed measuring system data acquisition

software in PC and probe scanning system

Experimental Setup for Magnetic Sensor

Reference material Scanning System Software LabVIEW

Reference Material (1) Normal defects and PVCs

Longitudinal and transverse defects

Def W L D Remarks

1 02 500 0213 (20 ) Inner defects

2 02 500 0427 (40 )

3 02 500 0213 (20 )Outer defectsPVC(1018)4 02 500 0427 (40 )

5 02 500 0639 (60 )

6 02 500 0852 (80 )

7 02 500 0639 (60 ) Inner defects

8 02 500 0852 (80 )

- 1 and 2 are inner defects

- 345 and 6 are outer defects with PVC

- 7 and 8 are inner defects

PVC

PVC

Defect Defect

For longitudinal defects and PVC For circumferential defects and PVC

ECT is very difficult to detect circumferential defects

We can distinguish PVCs and defects and longitudinal and circumferential defects

Flux-gate Magnetometer

One core sensor Two core sensor

3-축 flux-gate Magnetometer의 계략도

Sensorpia Co

pro

cess

or(

AV

R)

Sensor 1

RS422

Interface

Mic

ro-p

roce

ssor(

AV

R)

Sensor 2

Sensor 3

Interface

조립된 마그네토미터의 사진

Sensorpia Co

Analog PCB

Digital PCB

Sensorpia Co선형도(linearity)

10

20

30

40

50

60

y-axis

Magnetometer Output (microT)

-60 -50 -40 -30 -20 -10 0 10 20 30 40 50 60

-60

-50

-40

-30

-20

-10

0

10

Y-axis y=099946 x+0015STD 106E-4

Magnetometer Output (

Applied Magnetic Field (microT)

마그네토미터의 noise 특성 Sensorpia Co

1

10

100

y-axis

Magnetometer noise (nT)

0 1 2 3 4 5 6

1E-4

1E-3

001

01

Magnetometer noise (nT)

Frequency (Hz)

Magnetometer for KoDSAT

-150 -100 -50 0 50 100 150

-15

-10

-5

0

5

10

15

Magnetic Moment (Am

2)

Current (mA)

After Thermal Cycle Test

Measured

Resistance 193 ohm

Photograph of Magnetic torquer

Photograph of KoDSAT

Photograph of

3-axis Fluxgate

Magnetometer

Photograph of Magnetic torquer

Application of magnetometer

Moon magnetic fieldmeasurement

Telescope with direction indication

Joule Effect (Magnetostriction)

ϕ2cosel

l=

∆

0=∆

+∆

+∆

b

b

a

a

l

l

Actuator using Terfenol-D

00

05

10

B (T)

800

1000

1200

1400

1600

Magnetostriction (ppm)

-100 -50 0 50 100

-10

-05

00

B (T)

H (kAm)

2 MPa

4 MPa

6 MPa

8 MPa

10 MPa

12 MPa

-100 -50 0 50 100

-200

0

200

400

600

Magnetostriction (ppm)

H (kAm)

2 MPa

4 MPa

6 MPa

8 MPa

10 MPa

12 MPa

600

700

800

900

1000

-4 -3 -2 -1 0 1 2 3 4

0

10

20

30

40

50

60

Displacement (m

icro meter)

I (A)

FIELD

9 kAm

12 kAm

16 kAm

20 kAm

24 kAm

38 kAm

-50 -40 -30 -20 -10 0 10 20 30 40 50

-100

0

100

200

300

400

500

L (PPM)

H (kAm)

9 kAm

12 kAm

16 kAm

20 kAm

24 kAm

38 kAm

Magnetostrictive displacement sensor

Hysteresis loops under

tensile stress σ

(a) Crystalline 68 NiFe

λs = +25 10-6

(b) crystalline pure Ni λs

= -35 10-6

Villari Effect ( Inverse of Joule Effect)

= -35 10-6

(c) amorphous Co-based

alloy

λs = -35 10-6

ϕσλ 2sin2

3sdotsdot= smeE

γ

Permeability depending on the stress

σλmicromicro

1

3

2

Y

J

so

s

r =

γ

Calculated magnetization curves under stress

Variation of magnetization curve by an applied

tensile force (Co-based amorphous alloy)

Alloy Requirement

Materials for magnetoelastic sensors

Why amorphous magnetic materials are important

Stress-strain curves of several materials

Coercivity and hardness of several materials

Principles of magnetoelastic sensors

Non-contact torque sensor

Principle of cross torductor torque

sensor and flux pattern of sensor

poles on the surface of a shaft

a) without and b)with torsional load

Equivalent magnetic circuit of

cross type torque sensor

Helices of principal tensile and compressive stress on the surface of

a shaft subjected to torsion [32] Correlated changes of permeability

are detected by four-branch yoke system with sensing coils 123

and 4 and a common excitation pole

Examples of torque sensors

Four-branch type torque sensor

heads Pole structures realized

by commercial multi-pole

ferrites 14 and 18 min in

diameter (diameter of sensor

h e a d 1 7 a n d 2 4 m m

respectively) respectively)

Principle of Ring Torductor torque transducer

(a b) Physical structure (c) evolution of the

shaft surface under the transducer poles A and BRing torductor for measuring

torque on ship propeller shafts

(shaft diameter ca 500 mm)

(Courtesy ASEA Brown

Boveri AG)

Principal designs of coaxial torque sensors

Schematic diagram of data processing

electronics of a torque sensor

Extensometer (a) Construction of strain sensing element using

amorphous ribbon wound core (b) configuration of lumped

windings

∆E effect of an amorphous FeNi-based

alloy (Fe40 Ni38 Mo4 B18) Hs saturation

field

Magnetically tunable delay line

Torque Sensors using Amorphous wire

Sixtus tonk효과(large Barkhausen효과)

Hysteresis loops of a Wiegand wire for different reset fields

Curie 온도 및Hopkinson효과

Relation between normalised

saturation polarisation and

normalised Curie temperature

Permeability of a Mn-Zn ferrite as

a function of temperature and field

strength

Conclusions

1) Magnetic sensor 는 자동차 공장자동화 항공우주 및 군사용으로많이 사용되고 있다

2) 새로운 소재개발은 자기센서의 성능개발에 직접적인 영향을 준다2) 새로운 소재개발은 자기센서의 성능개발에 직접적인 영향을 준다

3) 센서의 개발을 위해서는 다양한 전공지식이 요구된다

(물리학 재료공학 기계공학 전자공학)

4) 센서분야가 고부가가치를 창출하는 부품사업이다

5) 핵심부품을 생산하는 중소기업의 item으로도 적절하다

10 pT

100 pT

1 pT

Noise spectrum of the developed search coil magnetometer

BJne

E xH

1minus=

neRH

1minus=

22 nP micromicro minus

Hall 효과

Bt

IRU H

HL =

2

22

)( he

eh

Hpne

nPR

micromicromicromicro

+

minus=

Rectangular Hall plate (cc1cc2 current constant sc1sc2

sensor constant I bias current U voltage drop UH Hall

voltage

Physics carrier concentration and kind of carrier measurement

Engineering magnetic field measurement

Current Measurement

Arrangement for noninvasive

current measurement using an iron

core The current to be measured

produces a proportional magnetic

field which can be measured in the

air gap

Characteristic curve produced by

the current

Arrangement for indirect noninvasive

current measurement using the

compensation principle An iron core as

represented in Figure 3-29 is held field

free by injection a current into a

compensating coil wound on the core

which offsets the field generated by the

current being measured The Hall effect

sensor in the air gap serves as a null

indicator

Circuit diagram for AC-power

measurement using a Hall effect

sensor

DC Power Measurement

Circuit diagram for DC-

power measurement using a

Hall effect sensor

Noncontact Position Sensing

Galvanomagnetic components for sensing the position of permanent magnets

and magnetically conductive materials

Current Sensor Based on Hall Sensor

and Magnetic Core for Hybrid Vehicle

KH Yeon1 SD Kim1 and D Son2 1Auto industry co14F Hanshin IT tower Guro Gu Seoul Korea2Hannam UniversityOjung dong 133 Daejeon Rep of Korea

i

Hall sensor

B

I

SB

ring core

B

I10

g

N

Bl S

micro

)( gtgtrmicro

gab core

Current Sensor Based on Hall

Sensor and Magnetic Core

Hall

Effect

Device

CurrentVoltage

applying for

Hall effect device

operation

Output

signals

Magnetic field

Occurred by

current measurement

Signal

process

circuits

Developed Current Sensor

Magnetic core

Hall sensor

PCB

25

30

35

40

45

50

Output voltage V

Current sensor(Open loop type)

Temp 25C

400A model

+400 ~ -400A

SD 000128

Linearity 003

Linearity of the sensor

Characteristics of the Current Sensors

1000A 10 V power supply

-500 -400 -300 -200 -100 0 100 200 300 400 500

00

05

10

15

20

Output voltage V

current A

Temperature 25Linearity 003

Measuring range -400A ~ +400A

1000A Electronic Load

-3

0

3

6

9

12

15

18

dB

Current sensor

DV2 PCB 24pF

40Aturns

Frequency bandwidth

Gain bandwidth 3 MHz

Current 10 A

Temperature 25

Frequency bandwidth 100 kHz

Sensor output voltage vs frequency

at applied current of 40 Aturns

1 10 100

-18

-15

-12

-9

-6

Frequency kHz 측정온도 25

주파수특성 30kHz 이상(3dB 기준)

측정전류 40Aturns(4A 10턴)

측정주파수 100Hz ~ 100kHz

Temperature 25Current 40Aturns

Frequency range 100 Hz ~ 100 kHz

What is Magnetoresistance

Magnetoresistance effect(AMR)

θθθ 2cos2

12sin12cos(

22 minusminus+∆asymp∆ xxxmx hhhRR

32 minusasymp∆ ρρ New effect GMR CMR and GMI

10 ge∆ ρρ

Two bridge configuration for

rotational angle measurement

measurement angle more than 180o

자동차 Engine Management System

Inductive and Eddy Current

Sensors Excited by Permanent Magnets

tNtU dd)( φsdotminus=

construction of an inductive

sensor (courtesy VDO Adolf sensor (courtesy VDO Adolf

Schindling AG)

1) constant socket

2) terminal package

3) permanent magnet

4) cap

5) soft magnetic core

6) coil

7) plate

8) blade connector

γγ

Sensor with yoke Change in the magnetic flux with

varying air gap Continuous lines

minimum air gap dashed lines

maximum air gap

C-shaped sensor

Sensor with radially

magnetized

permanent magnet

Signal Conditioning

Output voltage U of a DC-excited sensor with permanent

magnets when a single iron object passes by

Schematic electrical diagram of an inductive sensor

Linear Variable Differential Transformer

AC-Excited Sensors for Linear Movement

Principle of construction of an LVDT

Electrical circuit of an LVDT

tIMtNU dd dd sdotminus=sdotminus= φ

tIMtIMUUU dd dd 1212 sdotminussdot=minus=

tIMMU dd)( 12 sdotminus=

)(12 xMMMM =minus=

tIxMU dd)( sdot= tI

UxM

dd)( =

Signal Conditioning

power supply

carrier gen

autoampcontrol

LVDTcarrieramp

demod-ulator

phase

shifter

power supply

carrier gen

passivedemod-ulator

LVDTDCamp

Block diagram of a carrier amplifier system

Block diagram of a DC amplifier system

Variable Inductive Sensors

Principle of construction

of the VLP sensor

Principle of a bridge

circuit

lANL r 20 sdotsdotsdot= micromicro

21 BA UUU minus=

21)i(ii( 211 minus+sdot= LLLUU BA ωωω

)21))()((( minus∆minus+∆+∆+sdot= LLLLLLUU BA

)212)(( minus∆+sdot= LLLUU )212)(( minus∆+sdot= LLLUU BA

LLUU BA 21 ∆sdotsdot=

llLL ∆sdot=∆ d d

llLLUU BA ∆sdotsdot= d d)2(1

Applications and Properties

Principle of a construction of a force transducer

(courtesy Hottinger Baldwin Messtechnik)

Vibrationacceleration sensor

Signal Conditioning

Schematic electrical diagram of a force transducer connected with an

amplifier (courtesy Hottinger Baldwin Messtechnik GmbH)

Variable Gap Sensors

)( FeFe2

0 LLllANL micromicromicro +sdotsdot=

FeFe2

0max lANL sdotsdotsdot= micromicro

Construction of a variable gap sensor

Characteristic of a variable gap sensor

Construction of a differential

cross-anchor sensor

Output voltage U versus core

position x plusmn a limits of the

linear rage

Applications of differential cross-anchor sensors

AC-excited Sensors for Rotary Movements

Principle of construction of a synchro

α cos10 sdotsdot= UKU y

)120-( cos10 degsdotsdot= αUKU z

)240-( cos10 degsdotsdot= αUKU x

)120-( sin3100 degsdotsdotsdot=minus= αKUUUU yxyx

)240-( sin3100 degsdotsdotsdot=minus= αKUUUU zyzy

α sin3100 sdotsdotsdot=minus= KUUUU xzxz

Application to the Torque Sensor

Principle of construction of a torque-type synchro

Torque versus angular

difference

)( sin~ rt αα minussdotKM

)( cos~ rt1r αα minussdotUU

Principle of construction of a control-type sensor

Output voltage versus

angular difference

Principle of construction of a differential sychro

Eddy Current Sensors

tBE dd curl minus=JH = curl

0 div =BH(H)B sdot= micro

E(E)J sdot= σ

A B curl= A B curl=

tdd- A E =

)dd( tAJ minus= σ

tdd curl curl AA σmicro minus=

AA) σωmicro iminus= curl )(curl(1

AA) σωmicro i=∆)((1

Eddy Current Tachometer

Construction of a speedometer (courtesy VDO Adolf Schinding AG) 1) spindle 2) bearing

3) holding spring 4) iron yoke 5) eddy current cup 6) shaft of the magnet 7) support of

the magnet 8) temperature compensation 9) permanent magnet 10) torsion spring

Proximity Sensors

Schematic diagram of a proximity sensor

Output current of a proximity switch versus distance

Inductive Flowmeters

)( Btimessdot= υqF

EqF sdot=BE times=υ

)(ds Btimes== υEU )(ds Btimes== υEU

)( Bd timessdot= υU

Bsdotsdotsdot= υdKU

Development of magnetic phase detection

sensor for steam generator tube

Dirac Son1 Kwan-Sang Ryu2 Duck-Gun Park3

1Hannam University Daejeon Rep of Korea2Korea Research Institute of Standards and Science Daejeon Rep of Korea3KoreaAtomic Energy Research Institute Daejeon Rep of Korea

Introduction

The layout of pressurized water reactor (PWR) components

Primary side Secondary side (non-radioactive side)(radioactive side)

The Structure of SG(Steam Generator)(degradation mechanism)

Secondary SidePrimary Side

SCC

A B

A-B

Steam outlet

Anti-vibration

SCC

Fretting

Wall thinning

IGA

U-bend

In commercial power plants SG- height up to 21 m - weight up to 800 tons - 2~4 sets of SG were installed - SG can contain from 3000 to

16000 tubes each about 20 mmin diameter

Primary coolant outlet Primary coolant inlet

Anti-vibrationbars

Tubesupportplate

Tubesheet

IGA

SCC

Pitting

SCC

Inside Tubesheet

Top of Tubesheet

by SSHwang of KAERI

Denting

Sludge pile

in diameter

The SGT is made of nickel basedInconel alloy which is composed of 75 Ni 165Cr and 815Fe

-Degradation mechanism corrosion pitting denting inter granular attack

-Inspection Eddy current Testing(ECT)

Permeability Variation Clusters (PVC)

(Ferro-magnetic phase)

-005

000

005

010

015

m (emug)

1-1

-002

000

002

004

006

008

m (emug)

1-2

-1000 -500 0 500 1000

-015

-010

-005

H ( Am )

-1000 -500 0 500 1000

-006

-004

-002

H ( Am )

The hystresis loop in the fragment of PVC parts of Kori-1 retired SG tube

-004

-002

000

002

004

006

M (emug)

Inconel 600 tested at RT

under tensile stress

1 2 3

4 5 6

7 8 9-004

-002

000

002

004

006

M(emug)

Inconel 600 Heat treated at

602 oC under tensile stress

1 2 3

How can we detect magnetic phase

(PVC)selectively from the flaws in SGT

-3000 -2000 -1000 0 1000 2000 3000

-006

H (Oe)

7 8 9

10 11 12

-3000 -2000 -1000 0 1000 2000 3000

-006

-004

H(Oe)

4 5 6

7 8 9

The hysteresis loop of the tensile tested specimen at room temperature (a) and tensile tested at high temperature (b)

The magnetic phase can be created under the high temperature andpressure conditions which is correspond to the stress corrosion crackingin the SG tube in the NPP(Bruemmer SM Charlot LA amp Henager CH (1988) Corrosion 782)

Principle of ECT

If we can separate magnetic phase selectively from the

flaws using magnetic sensor the reliability of EC in SGT

inspection will be greatly enhanced

Structure of the permeability

sensor

Dimension and photograph of U-shape

sensing yoke

Design of Magnetic Sensor for PVC

sensor sensing yoke

Photograph of the completed sensor front side (above) and rear side (bottom)

R11R12

R10

R8

R6

R9

R13

R7

R14

C18

1 n

C17

C20

C21

D2

DIODE

SIN COS

-

+

U-2A

4

13

2

-

+

U-2B

75

6

8

-

+

U-3A

13

2

8

+5VC19

104

+5V

Schematic diagram of the sensor system

Electronic Circuit of Magnetic Sensor

R20

R

R21

R

-

+

U5AD797

3

26

74

U6

D1

S12

GND3

+VCC4VCC5

IN6

-VCC7

S28

C41

R13

R26

R18

R25

R2210 Ω

R16

R14

R17

10 k

R15

R27

R32

R28

R33

R29

R34

5 k

R30

C29

C37

104

C32473

C39473C40

104

C33

104

C21

104C23

104

C25

104

C26

104

C30

104

C31

104

C35

104

C36

104

C27

104

C28

104

C34

104

C38

104

D3

DIODE

L1

1

2

L2

1

2

L3

1

2

4

-

+

U-4A

4

13

2

-

+

U-4B

75

6

8

-

+

U-5A

4

13

2

-

+

U-5B

75

6

8

-

+

U-6A

4

13

2

-

+

U-6B

75

6

8

C22

104

-5V

+5V

+5V

+5V

+5V

+5V

+5V

U7

D1

S12

GND3

+VCC4

VCC5

IN6

-VCC7

S28

+5V

-5V

-5V

-5V

-5V

-5V

-5V

-5V

-5V

R19

R24

R

R23

R

C24

OUT(X)

OUT(Y)

R1

20 kR210 k

R3

20 kR410 k

C1

104

C8

104

REF43

OUT(X)

OUT(Y)

REF43

U2

+Vcc1

CH02

CH13

CH24

CH35

COMM6

SHDN7

Vref8

+Vcc9

GND10

GND11

DOUT12BUSY13DIN14CS15

DIN16

-

+

U-1A

13

2

8

-

+

U-1B

4

75

6

C410 uF

C5104

DOUT

C210uF

C6104

C3104

DCLK

C7104

DIN

C10

01uF

CS

BUSY

C14 10uF

J1

CON6

123456

D1

DIODE

R5

47K

C9

10uF

C1310uF

Y1

OSC

OUT3

GND2

VCC4

U3

RSTVPP1

GND10

VCC20

XTAL15

XTAL24

P10AIN012P11AIN113P1214P1315P1416P1517P1618P1719

P30RXD2

P31TXD3

P32INT06

P33INT17

P34T08

P35T19

P3711

U4

C1+1

C1-3

C2+4

C2-5

VCC16

GND15

V+2

V-6

R1OUT12

R2OUT9

T1IN11

T2IN10

R1IN13

R2IN8

T1OUT14

T2OUT7

C12 10uF

C16

01uF

C15 10uF

C11

01uF

-5V

+5V

+5V

+5V

+5V

+5V

+5V

+5V

RST

OSC

OSC

RST

DCLKCSDINBUSYDOUT

U1

IN2

GND

4

OUT6

TEMP3

TRIM5

-5V

+5V

Electronic circuit diagram of the magnetic sensor

Photograph of the completed measuring system data acquisition

software in PC and probe scanning system

Experimental Setup for Magnetic Sensor

Reference material Scanning System Software LabVIEW

Reference Material (1) Normal defects and PVCs

Longitudinal and transverse defects

Def W L D Remarks

1 02 500 0213 (20 ) Inner defects

2 02 500 0427 (40 )

3 02 500 0213 (20 )Outer defectsPVC(1018)4 02 500 0427 (40 )

5 02 500 0639 (60 )

6 02 500 0852 (80 )

7 02 500 0639 (60 ) Inner defects

8 02 500 0852 (80 )

- 1 and 2 are inner defects

- 345 and 6 are outer defects with PVC

- 7 and 8 are inner defects

PVC

PVC

Defect Defect

For longitudinal defects and PVC For circumferential defects and PVC

ECT is very difficult to detect circumferential defects

We can distinguish PVCs and defects and longitudinal and circumferential defects

Flux-gate Magnetometer

One core sensor Two core sensor

3-축 flux-gate Magnetometer의 계략도

Sensorpia Co

pro

cess

or(

AV

R)

Sensor 1

RS422

Interface

Mic

ro-p

roce

ssor(

AV

R)

Sensor 2

Sensor 3

Interface

조립된 마그네토미터의 사진

Sensorpia Co

Analog PCB

Digital PCB

Sensorpia Co선형도(linearity)

10

20

30

40

50

60

y-axis

Magnetometer Output (microT)

-60 -50 -40 -30 -20 -10 0 10 20 30 40 50 60

-60

-50

-40

-30

-20

-10

0

10

Y-axis y=099946 x+0015STD 106E-4

Magnetometer Output (

Applied Magnetic Field (microT)

마그네토미터의 noise 특성 Sensorpia Co

1

10

100

y-axis

Magnetometer noise (nT)

0 1 2 3 4 5 6

1E-4

1E-3

001

01

Magnetometer noise (nT)

Frequency (Hz)

Magnetometer for KoDSAT

-150 -100 -50 0 50 100 150

-15

-10

-5

0

5

10

15

Magnetic Moment (Am

2)

Current (mA)

After Thermal Cycle Test

Measured

Resistance 193 ohm

Photograph of Magnetic torquer

Photograph of KoDSAT

Photograph of

3-axis Fluxgate

Magnetometer

Photograph of Magnetic torquer

Application of magnetometer

Moon magnetic fieldmeasurement

Telescope with direction indication

Joule Effect (Magnetostriction)

ϕ2cosel

l=

∆

0=∆

+∆

+∆

b

b

a

a

l

l

Actuator using Terfenol-D

00

05

10

B (T)

800

1000

1200

1400

1600

Magnetostriction (ppm)

-100 -50 0 50 100

-10

-05

00

B (T)

H (kAm)

2 MPa

4 MPa

6 MPa

8 MPa

10 MPa

12 MPa

-100 -50 0 50 100

-200

0

200

400

600

Magnetostriction (ppm)

H (kAm)

2 MPa

4 MPa

6 MPa

8 MPa

10 MPa

12 MPa

600

700

800

900

1000

-4 -3 -2 -1 0 1 2 3 4

0

10

20

30

40

50

60

Displacement (m

icro meter)

I (A)

FIELD

9 kAm

12 kAm

16 kAm

20 kAm

24 kAm

38 kAm

-50 -40 -30 -20 -10 0 10 20 30 40 50

-100

0

100

200

300

400

500

L (PPM)

H (kAm)

9 kAm

12 kAm

16 kAm

20 kAm

24 kAm

38 kAm

Magnetostrictive displacement sensor

Hysteresis loops under

tensile stress σ

(a) Crystalline 68 NiFe

λs = +25 10-6

(b) crystalline pure Ni λs

= -35 10-6

Villari Effect ( Inverse of Joule Effect)

= -35 10-6

(c) amorphous Co-based

alloy

λs = -35 10-6

ϕσλ 2sin2

3sdotsdot= smeE

γ

Permeability depending on the stress

σλmicromicro

1

3

2

Y

J

so

s

r =

γ

Calculated magnetization curves under stress

Variation of magnetization curve by an applied

tensile force (Co-based amorphous alloy)

Alloy Requirement

Materials for magnetoelastic sensors

Why amorphous magnetic materials are important

Stress-strain curves of several materials

Coercivity and hardness of several materials

Principles of magnetoelastic sensors

Non-contact torque sensor

Principle of cross torductor torque

sensor and flux pattern of sensor

poles on the surface of a shaft

a) without and b)with torsional load

Equivalent magnetic circuit of

cross type torque sensor

Helices of principal tensile and compressive stress on the surface of

a shaft subjected to torsion [32] Correlated changes of permeability

are detected by four-branch yoke system with sensing coils 123

and 4 and a common excitation pole

Examples of torque sensors

Four-branch type torque sensor

heads Pole structures realized

by commercial multi-pole

ferrites 14 and 18 min in

diameter (diameter of sensor

h e a d 1 7 a n d 2 4 m m

respectively) respectively)

Principle of Ring Torductor torque transducer

(a b) Physical structure (c) evolution of the

shaft surface under the transducer poles A and BRing torductor for measuring

torque on ship propeller shafts

(shaft diameter ca 500 mm)

(Courtesy ASEA Brown

Boveri AG)

Principal designs of coaxial torque sensors

Schematic diagram of data processing

electronics of a torque sensor

Extensometer (a) Construction of strain sensing element using

amorphous ribbon wound core (b) configuration of lumped

windings

∆E effect of an amorphous FeNi-based

alloy (Fe40 Ni38 Mo4 B18) Hs saturation

field

Magnetically tunable delay line

Torque Sensors using Amorphous wire

Sixtus tonk효과(large Barkhausen효과)

Hysteresis loops of a Wiegand wire for different reset fields

Curie 온도 및Hopkinson효과

Relation between normalised

saturation polarisation and

normalised Curie temperature

Permeability of a Mn-Zn ferrite as

a function of temperature and field

strength

Conclusions

1) Magnetic sensor 는 자동차 공장자동화 항공우주 및 군사용으로많이 사용되고 있다

2) 새로운 소재개발은 자기센서의 성능개발에 직접적인 영향을 준다2) 새로운 소재개발은 자기센서의 성능개발에 직접적인 영향을 준다

3) 센서의 개발을 위해서는 다양한 전공지식이 요구된다

(물리학 재료공학 기계공학 전자공학)

4) 센서분야가 고부가가치를 창출하는 부품사업이다

5) 핵심부품을 생산하는 중소기업의 item으로도 적절하다

BJne

E xH

1minus=

neRH

1minus=

22 nP micromicro minus

Hall 효과

Bt

IRU H

HL =

2

22

)( he

eh

Hpne

nPR

micromicromicromicro

+

minus=

Rectangular Hall plate (cc1cc2 current constant sc1sc2

sensor constant I bias current U voltage drop UH Hall

voltage

Physics carrier concentration and kind of carrier measurement

Engineering magnetic field measurement

Current Measurement

Arrangement for noninvasive

current measurement using an iron

core The current to be measured

produces a proportional magnetic

field which can be measured in the

air gap

Characteristic curve produced by

the current

Arrangement for indirect noninvasive

current measurement using the

compensation principle An iron core as

represented in Figure 3-29 is held field

free by injection a current into a

compensating coil wound on the core

which offsets the field generated by the

current being measured The Hall effect

sensor in the air gap serves as a null

indicator

Circuit diagram for AC-power

measurement using a Hall effect

sensor

DC Power Measurement

Circuit diagram for DC-

power measurement using a

Hall effect sensor

Noncontact Position Sensing

Galvanomagnetic components for sensing the position of permanent magnets

and magnetically conductive materials

Current Sensor Based on Hall Sensor

and Magnetic Core for Hybrid Vehicle

KH Yeon1 SD Kim1 and D Son2 1Auto industry co14F Hanshin IT tower Guro Gu Seoul Korea2Hannam UniversityOjung dong 133 Daejeon Rep of Korea

i

Hall sensor

B

I

SB

ring core

B

I10

g

N

Bl S

micro

)( gtgtrmicro

gab core

Current Sensor Based on Hall

Sensor and Magnetic Core

Hall

Effect

Device

CurrentVoltage

applying for

Hall effect device

operation

Output

signals

Magnetic field

Occurred by

current measurement

Signal

process

circuits

Developed Current Sensor

Magnetic core

Hall sensor

PCB

25

30

35

40

45

50

Output voltage V

Current sensor(Open loop type)

Temp 25C

400A model

+400 ~ -400A

SD 000128

Linearity 003

Linearity of the sensor

Characteristics of the Current Sensors

1000A 10 V power supply

-500 -400 -300 -200 -100 0 100 200 300 400 500

00

05

10

15

20

Output voltage V

current A

Temperature 25Linearity 003

Measuring range -400A ~ +400A

1000A Electronic Load

-3

0

3

6

9

12

15

18

dB

Current sensor

DV2 PCB 24pF

40Aturns

Frequency bandwidth

Gain bandwidth 3 MHz

Current 10 A

Temperature 25

Frequency bandwidth 100 kHz

Sensor output voltage vs frequency

at applied current of 40 Aturns

1 10 100

-18

-15

-12

-9

-6

Frequency kHz 측정온도 25

주파수특성 30kHz 이상(3dB 기준)

측정전류 40Aturns(4A 10턴)

측정주파수 100Hz ~ 100kHz

Temperature 25Current 40Aturns

Frequency range 100 Hz ~ 100 kHz

What is Magnetoresistance

Magnetoresistance effect(AMR)

θθθ 2cos2

12sin12cos(

22 minusminus+∆asymp∆ xxxmx hhhRR

32 minusasymp∆ ρρ New effect GMR CMR and GMI

10 ge∆ ρρ

Two bridge configuration for

rotational angle measurement

measurement angle more than 180o

자동차 Engine Management System

Inductive and Eddy Current

Sensors Excited by Permanent Magnets

tNtU dd)( φsdotminus=

construction of an inductive

sensor (courtesy VDO Adolf sensor (courtesy VDO Adolf

Schindling AG)

1) constant socket

2) terminal package

3) permanent magnet

4) cap

5) soft magnetic core

6) coil

7) plate

8) blade connector

γγ

Sensor with yoke Change in the magnetic flux with

varying air gap Continuous lines

minimum air gap dashed lines

maximum air gap

C-shaped sensor

Sensor with radially

magnetized

permanent magnet

Signal Conditioning

Output voltage U of a DC-excited sensor with permanent

magnets when a single iron object passes by

Schematic electrical diagram of an inductive sensor

Linear Variable Differential Transformer

AC-Excited Sensors for Linear Movement

Principle of construction of an LVDT

Electrical circuit of an LVDT

tIMtNU dd dd sdotminus=sdotminus= φ

tIMtIMUUU dd dd 1212 sdotminussdot=minus=

tIMMU dd)( 12 sdotminus=

)(12 xMMMM =minus=

tIxMU dd)( sdot= tI

UxM

dd)( =

Signal Conditioning

power supply

carrier gen

autoampcontrol

LVDTcarrieramp

demod-ulator

phase

shifter

power supply

carrier gen

passivedemod-ulator

LVDTDCamp

Block diagram of a carrier amplifier system

Block diagram of a DC amplifier system

Variable Inductive Sensors

Principle of construction

of the VLP sensor

Principle of a bridge

circuit

lANL r 20 sdotsdotsdot= micromicro

21 BA UUU minus=

21)i(ii( 211 minus+sdot= LLLUU BA ωωω

)21))()((( minus∆minus+∆+∆+sdot= LLLLLLUU BA

)212)(( minus∆+sdot= LLLUU )212)(( minus∆+sdot= LLLUU BA

LLUU BA 21 ∆sdotsdot=

llLL ∆sdot=∆ d d

llLLUU BA ∆sdotsdot= d d)2(1

Applications and Properties

Principle of a construction of a force transducer

(courtesy Hottinger Baldwin Messtechnik)

Vibrationacceleration sensor

Signal Conditioning

Schematic electrical diagram of a force transducer connected with an

amplifier (courtesy Hottinger Baldwin Messtechnik GmbH)

Variable Gap Sensors

)( FeFe2

0 LLllANL micromicromicro +sdotsdot=

FeFe2

0max lANL sdotsdotsdot= micromicro

Construction of a variable gap sensor

Characteristic of a variable gap sensor

Construction of a differential

cross-anchor sensor

Output voltage U versus core

position x plusmn a limits of the

linear rage

Applications of differential cross-anchor sensors

AC-excited Sensors for Rotary Movements

Principle of construction of a synchro

α cos10 sdotsdot= UKU y

)120-( cos10 degsdotsdot= αUKU z

)240-( cos10 degsdotsdot= αUKU x

)120-( sin3100 degsdotsdotsdot=minus= αKUUUU yxyx

)240-( sin3100 degsdotsdotsdot=minus= αKUUUU zyzy

α sin3100 sdotsdotsdot=minus= KUUUU xzxz

Application to the Torque Sensor

Principle of construction of a torque-type synchro

Torque versus angular

difference

)( sin~ rt αα minussdotKM

)( cos~ rt1r αα minussdotUU

Principle of construction of a control-type sensor

Output voltage versus

angular difference

Principle of construction of a differential sychro

Eddy Current Sensors

tBE dd curl minus=JH = curl

0 div =BH(H)B sdot= micro

E(E)J sdot= σ

A B curl= A B curl=

tdd- A E =

)dd( tAJ minus= σ

tdd curl curl AA σmicro minus=

AA) σωmicro iminus= curl )(curl(1

AA) σωmicro i=∆)((1

Eddy Current Tachometer

Construction of a speedometer (courtesy VDO Adolf Schinding AG) 1) spindle 2) bearing

3) holding spring 4) iron yoke 5) eddy current cup 6) shaft of the magnet 7) support of

the magnet 8) temperature compensation 9) permanent magnet 10) torsion spring

Proximity Sensors

Schematic diagram of a proximity sensor

Output current of a proximity switch versus distance

Inductive Flowmeters

)( Btimessdot= υqF

EqF sdot=BE times=υ

)(ds Btimes== υEU )(ds Btimes== υEU

)( Bd timessdot= υU

Bsdotsdotsdot= υdKU

Development of magnetic phase detection

sensor for steam generator tube

Dirac Son1 Kwan-Sang Ryu2 Duck-Gun Park3

1Hannam University Daejeon Rep of Korea2Korea Research Institute of Standards and Science Daejeon Rep of Korea3KoreaAtomic Energy Research Institute Daejeon Rep of Korea

Introduction

The layout of pressurized water reactor (PWR) components

Primary side Secondary side (non-radioactive side)(radioactive side)

The Structure of SG(Steam Generator)(degradation mechanism)

Secondary SidePrimary Side

SCC

A B

A-B

Steam outlet

Anti-vibration

SCC

Fretting

Wall thinning

IGA

U-bend

In commercial power plants SG- height up to 21 m - weight up to 800 tons - 2~4 sets of SG were installed - SG can contain from 3000 to

16000 tubes each about 20 mmin diameter

Primary coolant outlet Primary coolant inlet

Anti-vibrationbars

Tubesupportplate

Tubesheet

IGA

SCC

Pitting

SCC

Inside Tubesheet

Top of Tubesheet

by SSHwang of KAERI

Denting

Sludge pile

in diameter

The SGT is made of nickel basedInconel alloy which is composed of 75 Ni 165Cr and 815Fe

-Degradation mechanism corrosion pitting denting inter granular attack

-Inspection Eddy current Testing(ECT)

Permeability Variation Clusters (PVC)

(Ferro-magnetic phase)

-005

000

005

010

015

m (emug)

1-1

-002

000

002

004

006

008

m (emug)

1-2

-1000 -500 0 500 1000

-015

-010

-005

H ( Am )

-1000 -500 0 500 1000

-006

-004

-002

H ( Am )

The hystresis loop in the fragment of PVC parts of Kori-1 retired SG tube

-004

-002

000

002

004

006

M (emug)

Inconel 600 tested at RT

under tensile stress

1 2 3

4 5 6

7 8 9-004

-002

000

002

004

006

M(emug)

Inconel 600 Heat treated at

602 oC under tensile stress

1 2 3

How can we detect magnetic phase

(PVC)selectively from the flaws in SGT

-3000 -2000 -1000 0 1000 2000 3000

-006

H (Oe)

7 8 9

10 11 12

-3000 -2000 -1000 0 1000 2000 3000

-006

-004

H(Oe)

4 5 6

7 8 9

The hysteresis loop of the tensile tested specimen at room temperature (a) and tensile tested at high temperature (b)

The magnetic phase can be created under the high temperature andpressure conditions which is correspond to the stress corrosion crackingin the SG tube in the NPP(Bruemmer SM Charlot LA amp Henager CH (1988) Corrosion 782)

Principle of ECT

If we can separate magnetic phase selectively from the

flaws using magnetic sensor the reliability of EC in SGT

inspection will be greatly enhanced

Structure of the permeability

sensor

Dimension and photograph of U-shape

sensing yoke

Design of Magnetic Sensor for PVC

sensor sensing yoke

Photograph of the completed sensor front side (above) and rear side (bottom)

R11R12

R10

R8

R6

R9

R13

R7

R14

C18

1 n

C17

C20

C21

D2

DIODE

SIN COS

-

+

U-2A

4

13

2

-

+

U-2B

75

6

8

-

+

U-3A

13

2

8

+5VC19

104

+5V

Schematic diagram of the sensor system

Electronic Circuit of Magnetic Sensor

R20

R

R21

R

-

+

U5AD797

3

26

74

U6

D1

S12

GND3

+VCC4VCC5

IN6

-VCC7

S28

C41

R13

R26

R18

R25

R2210 Ω

R16

R14

R17

10 k

R15

R27

R32

R28

R33

R29

R34

5 k

R30

C29

C37

104

C32473

C39473C40

104

C33

104

C21

104C23

104

C25

104

C26

104

C30

104

C31

104

C35

104

C36

104

C27

104

C28

104

C34

104

C38

104

D3

DIODE

L1

1

2

L2

1

2

L3

1

2

4

-

+

U-4A

4

13

2

-

+

U-4B

75

6

8

-

+

U-5A

4

13

2

-

+

U-5B

75

6

8

-

+

U-6A

4

13

2

-

+

U-6B

75

6

8

C22

104

-5V

+5V

+5V

+5V

+5V

+5V

+5V

U7

D1

S12

GND3

+VCC4

VCC5

IN6

-VCC7

S28

+5V

-5V

-5V

-5V

-5V

-5V

-5V

-5V

-5V

R19

R24

R

R23

R

C24

OUT(X)

OUT(Y)

R1

20 kR210 k

R3

20 kR410 k

C1

104

C8

104

REF43

OUT(X)

OUT(Y)

REF43

U2

+Vcc1

CH02

CH13

CH24

CH35

COMM6

SHDN7

Vref8

+Vcc9

GND10

GND11

DOUT12BUSY13DIN14CS15

DIN16

-

+

U-1A

13

2

8

-

+

U-1B

4

75

6

C410 uF

C5104

DOUT

C210uF

C6104

C3104

DCLK

C7104

DIN

C10

01uF

CS

BUSY

C14 10uF

J1

CON6

123456

D1

DIODE

R5

47K

C9

10uF

C1310uF

Y1

OSC

OUT3

GND2

VCC4

U3

RSTVPP1

GND10

VCC20

XTAL15

XTAL24

P10AIN012P11AIN113P1214P1315P1416P1517P1618P1719

P30RXD2

P31TXD3

P32INT06

P33INT17

P34T08

P35T19

P3711

U4

C1+1

C1-3

C2+4

C2-5

VCC16

GND15

V+2

V-6

R1OUT12

R2OUT9

T1IN11

T2IN10

R1IN13

R2IN8

T1OUT14

T2OUT7

C12 10uF

C16

01uF

C15 10uF

C11

01uF

-5V

+5V

+5V

+5V

+5V

+5V

+5V

+5V

RST

OSC

OSC

RST

DCLKCSDINBUSYDOUT

U1

IN2

GND

4

OUT6

TEMP3

TRIM5

-5V

+5V

Electronic circuit diagram of the magnetic sensor

Photograph of the completed measuring system data acquisition

software in PC and probe scanning system

Experimental Setup for Magnetic Sensor

Reference material Scanning System Software LabVIEW

Reference Material (1) Normal defects and PVCs

Longitudinal and transverse defects

Def W L D Remarks

1 02 500 0213 (20 ) Inner defects

2 02 500 0427 (40 )

3 02 500 0213 (20 )Outer defectsPVC(1018)4 02 500 0427 (40 )

5 02 500 0639 (60 )

6 02 500 0852 (80 )

7 02 500 0639 (60 ) Inner defects

8 02 500 0852 (80 )

- 1 and 2 are inner defects

- 345 and 6 are outer defects with PVC

- 7 and 8 are inner defects

PVC

PVC

Defect Defect

For longitudinal defects and PVC For circumferential defects and PVC

ECT is very difficult to detect circumferential defects

We can distinguish PVCs and defects and longitudinal and circumferential defects

Flux-gate Magnetometer

One core sensor Two core sensor

3-축 flux-gate Magnetometer의 계략도

Sensorpia Co

pro

cess

or(

AV

R)

Sensor 1

RS422

Interface

Mic

ro-p

roce

ssor(

AV

R)

Sensor 2

Sensor 3

Interface

조립된 마그네토미터의 사진

Sensorpia Co

Analog PCB

Digital PCB

Sensorpia Co선형도(linearity)

10

20

30

40

50

60

y-axis

Magnetometer Output (microT)

-60 -50 -40 -30 -20 -10 0 10 20 30 40 50 60

-60

-50

-40

-30

-20

-10

0

10

Y-axis y=099946 x+0015STD 106E-4

Magnetometer Output (

Applied Magnetic Field (microT)

마그네토미터의 noise 특성 Sensorpia Co

1

10

100

y-axis

Magnetometer noise (nT)

0 1 2 3 4 5 6

1E-4

1E-3

001

01

Magnetometer noise (nT)

Frequency (Hz)

Magnetometer for KoDSAT

-150 -100 -50 0 50 100 150

-15

-10

-5

0

5

10

15

Magnetic Moment (Am

2)

Current (mA)

After Thermal Cycle Test

Measured

Resistance 193 ohm

Photograph of Magnetic torquer

Photograph of KoDSAT

Photograph of

3-axis Fluxgate

Magnetometer

Photograph of Magnetic torquer

Application of magnetometer

Moon magnetic fieldmeasurement

Telescope with direction indication

Joule Effect (Magnetostriction)

ϕ2cosel

l=

∆

0=∆

+∆

+∆

b

b

a

a

l

l

Actuator using Terfenol-D

00

05

10

B (T)

800

1000

1200

1400

1600

Magnetostriction (ppm)

-100 -50 0 50 100

-10

-05

00

B (T)

H (kAm)

2 MPa

4 MPa

6 MPa

8 MPa

10 MPa

12 MPa

-100 -50 0 50 100

-200

0

200

400

600

Magnetostriction (ppm)

H (kAm)

2 MPa

4 MPa

6 MPa

8 MPa

10 MPa

12 MPa

600

700

800

900

1000

-4 -3 -2 -1 0 1 2 3 4

0

10

20

30

40

50

60

Displacement (m

icro meter)

I (A)

FIELD

9 kAm

12 kAm

16 kAm

20 kAm

24 kAm

38 kAm

-50 -40 -30 -20 -10 0 10 20 30 40 50

-100

0

100

200

300

400

500

L (PPM)

H (kAm)

9 kAm

12 kAm

16 kAm

20 kAm

24 kAm

38 kAm

Magnetostrictive displacement sensor

Hysteresis loops under

tensile stress σ

(a) Crystalline 68 NiFe

λs = +25 10-6

(b) crystalline pure Ni λs

= -35 10-6

Villari Effect ( Inverse of Joule Effect)

= -35 10-6

(c) amorphous Co-based

alloy

λs = -35 10-6

ϕσλ 2sin2

3sdotsdot= smeE

γ

Permeability depending on the stress

σλmicromicro

1

3

2

Y

J

so

s

r =

γ

Calculated magnetization curves under stress

Variation of magnetization curve by an applied

tensile force (Co-based amorphous alloy)

Alloy Requirement

Materials for magnetoelastic sensors

Why amorphous magnetic materials are important

Stress-strain curves of several materials

Coercivity and hardness of several materials

Principles of magnetoelastic sensors

Non-contact torque sensor

Principle of cross torductor torque

sensor and flux pattern of sensor

poles on the surface of a shaft

a) without and b)with torsional load

Equivalent magnetic circuit of

cross type torque sensor

Helices of principal tensile and compressive stress on the surface of

a shaft subjected to torsion [32] Correlated changes of permeability

are detected by four-branch yoke system with sensing coils 123

and 4 and a common excitation pole

Examples of torque sensors

Four-branch type torque sensor

heads Pole structures realized

by commercial multi-pole

ferrites 14 and 18 min in

diameter (diameter of sensor

h e a d 1 7 a n d 2 4 m m

respectively) respectively)

Principle of Ring Torductor torque transducer

(a b) Physical structure (c) evolution of the

shaft surface under the transducer poles A and BRing torductor for measuring

torque on ship propeller shafts

(shaft diameter ca 500 mm)

(Courtesy ASEA Brown

Boveri AG)

Principal designs of coaxial torque sensors

Schematic diagram of data processing

electronics of a torque sensor

Extensometer (a) Construction of strain sensing element using

amorphous ribbon wound core (b) configuration of lumped

windings

∆E effect of an amorphous FeNi-based

alloy (Fe40 Ni38 Mo4 B18) Hs saturation

field

Magnetically tunable delay line

Torque Sensors using Amorphous wire

Sixtus tonk효과(large Barkhausen효과)

Hysteresis loops of a Wiegand wire for different reset fields

Curie 온도 및Hopkinson효과

Relation between normalised

saturation polarisation and

normalised Curie temperature

Permeability of a Mn-Zn ferrite as

a function of temperature and field

strength

Conclusions

1) Magnetic sensor 는 자동차 공장자동화 항공우주 및 군사용으로많이 사용되고 있다

2) 새로운 소재개발은 자기센서의 성능개발에 직접적인 영향을 준다2) 새로운 소재개발은 자기센서의 성능개발에 직접적인 영향을 준다

3) 센서의 개발을 위해서는 다양한 전공지식이 요구된다

(물리학 재료공학 기계공학 전자공학)

4) 센서분야가 고부가가치를 창출하는 부품사업이다

5) 핵심부품을 생산하는 중소기업의 item으로도 적절하다

Current Measurement

Arrangement for noninvasive

current measurement using an iron

core The current to be measured

produces a proportional magnetic

field which can be measured in the

air gap

Characteristic curve produced by

the current

Arrangement for indirect noninvasive

current measurement using the

compensation principle An iron core as

represented in Figure 3-29 is held field

free by injection a current into a

compensating coil wound on the core

which offsets the field generated by the

current being measured The Hall effect

sensor in the air gap serves as a null

indicator

Circuit diagram for AC-power

measurement using a Hall effect

sensor

DC Power Measurement

Circuit diagram for DC-

power measurement using a

Hall effect sensor

Noncontact Position Sensing

Galvanomagnetic components for sensing the position of permanent magnets

and magnetically conductive materials

Current Sensor Based on Hall Sensor

and Magnetic Core for Hybrid Vehicle

KH Yeon1 SD Kim1 and D Son2 1Auto industry co14F Hanshin IT tower Guro Gu Seoul Korea2Hannam UniversityOjung dong 133 Daejeon Rep of Korea

i

Hall sensor

B

I

SB

ring core

B

I10

g

N

Bl S

micro

)( gtgtrmicro

gab core

Current Sensor Based on Hall

Sensor and Magnetic Core

Hall

Effect

Device

CurrentVoltage

applying for

Hall effect device

operation

Output

signals

Magnetic field

Occurred by

current measurement

Signal

process

circuits

Developed Current Sensor

Magnetic core

Hall sensor

PCB

25

30

35

40

45

50

Output voltage V

Current sensor(Open loop type)

Temp 25C

400A model

+400 ~ -400A

SD 000128

Linearity 003

Linearity of the sensor

Characteristics of the Current Sensors

1000A 10 V power supply

-500 -400 -300 -200 -100 0 100 200 300 400 500

00

05

10

15

20

Output voltage V

current A

Temperature 25Linearity 003

Measuring range -400A ~ +400A

1000A Electronic Load

-3

0

3

6

9

12

15

18

dB

Current sensor

DV2 PCB 24pF

40Aturns

Frequency bandwidth

Gain bandwidth 3 MHz

Current 10 A

Temperature 25

Frequency bandwidth 100 kHz

Sensor output voltage vs frequency

at applied current of 40 Aturns

1 10 100

-18

-15

-12

-9

-6

Frequency kHz 측정온도 25

주파수특성 30kHz 이상(3dB 기준)

측정전류 40Aturns(4A 10턴)

측정주파수 100Hz ~ 100kHz

Temperature 25Current 40Aturns

Frequency range 100 Hz ~ 100 kHz

What is Magnetoresistance

Magnetoresistance effect(AMR)

θθθ 2cos2

12sin12cos(

22 minusminus+∆asymp∆ xxxmx hhhRR

32 minusasymp∆ ρρ New effect GMR CMR and GMI

10 ge∆ ρρ

Two bridge configuration for

rotational angle measurement

measurement angle more than 180o

자동차 Engine Management System

Inductive and Eddy Current

Sensors Excited by Permanent Magnets

tNtU dd)( φsdotminus=

construction of an inductive

sensor (courtesy VDO Adolf sensor (courtesy VDO Adolf

Schindling AG)

1) constant socket

2) terminal package

3) permanent magnet

4) cap

5) soft magnetic core

6) coil

7) plate

8) blade connector

γγ

Sensor with yoke Change in the magnetic flux with

varying air gap Continuous lines

minimum air gap dashed lines

maximum air gap

C-shaped sensor

Sensor with radially

magnetized

permanent magnet

Signal Conditioning

Output voltage U of a DC-excited sensor with permanent

magnets when a single iron object passes by

Schematic electrical diagram of an inductive sensor

Linear Variable Differential Transformer

AC-Excited Sensors for Linear Movement

Principle of construction of an LVDT

Electrical circuit of an LVDT

tIMtNU dd dd sdotminus=sdotminus= φ

tIMtIMUUU dd dd 1212 sdotminussdot=minus=

tIMMU dd)( 12 sdotminus=

)(12 xMMMM =minus=

tIxMU dd)( sdot= tI

UxM

dd)( =

Signal Conditioning

power supply

carrier gen

autoampcontrol

LVDTcarrieramp

demod-ulator

phase

shifter

power supply

carrier gen

passivedemod-ulator

LVDTDCamp

Block diagram of a carrier amplifier system

Block diagram of a DC amplifier system

Variable Inductive Sensors

Principle of construction

of the VLP sensor

Principle of a bridge

circuit

lANL r 20 sdotsdotsdot= micromicro

21 BA UUU minus=

21)i(ii( 211 minus+sdot= LLLUU BA ωωω

)21))()((( minus∆minus+∆+∆+sdot= LLLLLLUU BA

)212)(( minus∆+sdot= LLLUU )212)(( minus∆+sdot= LLLUU BA

LLUU BA 21 ∆sdotsdot=

llLL ∆sdot=∆ d d

llLLUU BA ∆sdotsdot= d d)2(1

Applications and Properties

Principle of a construction of a force transducer

(courtesy Hottinger Baldwin Messtechnik)

Vibrationacceleration sensor

Signal Conditioning

Schematic electrical diagram of a force transducer connected with an

amplifier (courtesy Hottinger Baldwin Messtechnik GmbH)

Variable Gap Sensors

)( FeFe2

0 LLllANL micromicromicro +sdotsdot=

FeFe2

0max lANL sdotsdotsdot= micromicro

Construction of a variable gap sensor

Characteristic of a variable gap sensor

Construction of a differential

cross-anchor sensor

Output voltage U versus core

position x plusmn a limits of the

linear rage

Applications of differential cross-anchor sensors

AC-excited Sensors for Rotary Movements

Principle of construction of a synchro

α cos10 sdotsdot= UKU y

)120-( cos10 degsdotsdot= αUKU z

)240-( cos10 degsdotsdot= αUKU x

)120-( sin3100 degsdotsdotsdot=minus= αKUUUU yxyx

)240-( sin3100 degsdotsdotsdot=minus= αKUUUU zyzy

α sin3100 sdotsdotsdot=minus= KUUUU xzxz

Application to the Torque Sensor

Principle of construction of a torque-type synchro

Torque versus angular

difference

)( sin~ rt αα minussdotKM

)( cos~ rt1r αα minussdotUU

Principle of construction of a control-type sensor

Output voltage versus

angular difference

Principle of construction of a differential sychro

Eddy Current Sensors

tBE dd curl minus=JH = curl

0 div =BH(H)B sdot= micro

E(E)J sdot= σ

A B curl= A B curl=

tdd- A E =

)dd( tAJ minus= σ

tdd curl curl AA σmicro minus=

AA) σωmicro iminus= curl )(curl(1

AA) σωmicro i=∆)((1

Eddy Current Tachometer

Construction of a speedometer (courtesy VDO Adolf Schinding AG) 1) spindle 2) bearing

3) holding spring 4) iron yoke 5) eddy current cup 6) shaft of the magnet 7) support of

the magnet 8) temperature compensation 9) permanent magnet 10) torsion spring

Proximity Sensors

Schematic diagram of a proximity sensor

Output current of a proximity switch versus distance

Inductive Flowmeters

)( Btimessdot= υqF

EqF sdot=BE times=υ

)(ds Btimes== υEU )(ds Btimes== υEU

)( Bd timessdot= υU

Bsdotsdotsdot= υdKU

Development of magnetic phase detection

sensor for steam generator tube

Dirac Son1 Kwan-Sang Ryu2 Duck-Gun Park3

1Hannam University Daejeon Rep of Korea2Korea Research Institute of Standards and Science Daejeon Rep of Korea3KoreaAtomic Energy Research Institute Daejeon Rep of Korea

Introduction

The layout of pressurized water reactor (PWR) components

Primary side Secondary side (non-radioactive side)(radioactive side)

The Structure of SG(Steam Generator)(degradation mechanism)

Secondary SidePrimary Side

SCC

A B

A-B

Steam outlet

Anti-vibration

SCC

Fretting

Wall thinning

IGA

U-bend

In commercial power plants SG- height up to 21 m - weight up to 800 tons - 2~4 sets of SG were installed - SG can contain from 3000 to

16000 tubes each about 20 mmin diameter

Primary coolant outlet Primary coolant inlet

Anti-vibrationbars

Tubesupportplate

Tubesheet

IGA

SCC

Pitting

SCC

Inside Tubesheet

Top of Tubesheet

by SSHwang of KAERI

Denting

Sludge pile

in diameter

The SGT is made of nickel basedInconel alloy which is composed of 75 Ni 165Cr and 815Fe

-Degradation mechanism corrosion pitting denting inter granular attack

-Inspection Eddy current Testing(ECT)

Permeability Variation Clusters (PVC)

(Ferro-magnetic phase)

-005

000

005

010

015

m (emug)

1-1

-002

000

002

004

006

008

m (emug)

1-2

-1000 -500 0 500 1000

-015

-010

-005

H ( Am )

-1000 -500 0 500 1000

-006

-004

-002

H ( Am )

The hystresis loop in the fragment of PVC parts of Kori-1 retired SG tube

-004

-002

000

002

004

006

M (emug)

Inconel 600 tested at RT

under tensile stress

1 2 3

4 5 6

7 8 9-004

-002

000

002

004

006

M(emug)

Inconel 600 Heat treated at

602 oC under tensile stress

1 2 3

How can we detect magnetic phase

(PVC)selectively from the flaws in SGT

-3000 -2000 -1000 0 1000 2000 3000

-006

H (Oe)

7 8 9

10 11 12

-3000 -2000 -1000 0 1000 2000 3000

-006

-004

H(Oe)

4 5 6

7 8 9

The hysteresis loop of the tensile tested specimen at room temperature (a) and tensile tested at high temperature (b)

The magnetic phase can be created under the high temperature andpressure conditions which is correspond to the stress corrosion crackingin the SG tube in the NPP(Bruemmer SM Charlot LA amp Henager CH (1988) Corrosion 782)

Principle of ECT

If we can separate magnetic phase selectively from the

flaws using magnetic sensor the reliability of EC in SGT

inspection will be greatly enhanced

Structure of the permeability

sensor

Dimension and photograph of U-shape

sensing yoke

Design of Magnetic Sensor for PVC

sensor sensing yoke

Photograph of the completed sensor front side (above) and rear side (bottom)

R11R12

R10

R8

R6

R9

R13

R7

R14

C18

1 n

C17

C20

C21

D2

DIODE

SIN COS

-

+

U-2A

4

13

2

-

+

U-2B

75

6

8

-

+

U-3A

13

2

8

+5VC19

104

+5V

Schematic diagram of the sensor system

Electronic Circuit of Magnetic Sensor

R20

R

R21

R

-

+

U5AD797

3

26

74

U6

D1

S12

GND3

+VCC4VCC5

IN6

-VCC7

S28

C41

R13

R26

R18

R25

R2210 Ω

R16

R14

R17

10 k

R15

R27

R32

R28

R33

R29

R34

5 k

R30

C29

C37

104

C32473

C39473C40

104

C33

104

C21

104C23

104

C25

104

C26

104

C30

104

C31

104

C35

104

C36

104

C27

104

C28

104

C34

104

C38

104

D3

DIODE

L1

1

2

L2

1

2

L3

1

2

4

-

+

U-4A

4

13

2

-

+

U-4B

75

6

8

-

+

U-5A

4

13

2

-

+

U-5B

75

6

8

-

+

U-6A

4

13

2

-

+

U-6B

75

6

8

C22

104

-5V

+5V

+5V

+5V

+5V

+5V

+5V

U7

D1

S12

GND3

+VCC4

VCC5

IN6

-VCC7

S28

+5V

-5V

-5V

-5V

-5V

-5V

-5V

-5V

-5V

R19

R24

R

R23

R

C24

OUT(X)

OUT(Y)

R1

20 kR210 k

R3

20 kR410 k

C1

104

C8

104

REF43

OUT(X)

OUT(Y)

REF43

U2

+Vcc1

CH02

CH13

CH24

CH35

COMM6

SHDN7

Vref8

+Vcc9

GND10

GND11

DOUT12BUSY13DIN14CS15

DIN16

-

+

U-1A

13

2

8

-

+

U-1B

4

75

6

C410 uF

C5104

DOUT

C210uF

C6104

C3104

DCLK

C7104

DIN

C10

01uF

CS

BUSY

C14 10uF

J1

CON6

123456

D1

DIODE

R5

47K

C9

10uF

C1310uF

Y1

OSC

OUT3

GND2

VCC4

U3

RSTVPP1

GND10

VCC20

XTAL15

XTAL24

P10AIN012P11AIN113P1214P1315P1416P1517P1618P1719

P30RXD2

P31TXD3

P32INT06

P33INT17

P34T08

P35T19

P3711

U4

C1+1

C1-3

C2+4

C2-5

VCC16

GND15

V+2

V-6

R1OUT12

R2OUT9

T1IN11

T2IN10

R1IN13

R2IN8

T1OUT14

T2OUT7

C12 10uF

C16

01uF

C15 10uF

C11

01uF

-5V

+5V

+5V

+5V

+5V

+5V

+5V

+5V

RST

OSC

OSC

RST

DCLKCSDINBUSYDOUT

U1

IN2

GND

4

OUT6

TEMP3

TRIM5

-5V

+5V

Electronic circuit diagram of the magnetic sensor

Photograph of the completed measuring system data acquisition

software in PC and probe scanning system

Experimental Setup for Magnetic Sensor

Reference material Scanning System Software LabVIEW

Reference Material (1) Normal defects and PVCs

Longitudinal and transverse defects

Def W L D Remarks

1 02 500 0213 (20 ) Inner defects

2 02 500 0427 (40 )

3 02 500 0213 (20 )Outer defectsPVC(1018)4 02 500 0427 (40 )

5 02 500 0639 (60 )

6 02 500 0852 (80 )

7 02 500 0639 (60 ) Inner defects

8 02 500 0852 (80 )

- 1 and 2 are inner defects

- 345 and 6 are outer defects with PVC

- 7 and 8 are inner defects

PVC

PVC

Defect Defect

For longitudinal defects and PVC For circumferential defects and PVC

ECT is very difficult to detect circumferential defects

We can distinguish PVCs and defects and longitudinal and circumferential defects

Flux-gate Magnetometer

One core sensor Two core sensor

3-축 flux-gate Magnetometer의 계략도

Sensorpia Co

pro

cess

or(

AV

R)

Sensor 1

RS422

Interface

Mic

ro-p

roce

ssor(

AV

R)

Sensor 2

Sensor 3

Interface

조립된 마그네토미터의 사진

Sensorpia Co

Analog PCB

Digital PCB

Sensorpia Co선형도(linearity)

10

20

30

40

50

60

y-axis

Magnetometer Output (microT)

-60 -50 -40 -30 -20 -10 0 10 20 30 40 50 60

-60

-50

-40

-30

-20

-10

0

10

Y-axis y=099946 x+0015STD 106E-4

Magnetometer Output (

Applied Magnetic Field (microT)

마그네토미터의 noise 특성 Sensorpia Co

1

10

100

y-axis

Magnetometer noise (nT)

0 1 2 3 4 5 6

1E-4

1E-3

001

01

Magnetometer noise (nT)

Frequency (Hz)

Magnetometer for KoDSAT

-150 -100 -50 0 50 100 150

-15

-10

-5

0

5

10

15

Magnetic Moment (Am

2)

Current (mA)

After Thermal Cycle Test

Measured

Resistance 193 ohm

Photograph of Magnetic torquer

Photograph of KoDSAT

Photograph of

3-axis Fluxgate

Magnetometer

Photograph of Magnetic torquer

Application of magnetometer

Moon magnetic fieldmeasurement

Telescope with direction indication

Joule Effect (Magnetostriction)

ϕ2cosel

l=

∆

0=∆

+∆

+∆

b

b

a

a

l

l

Actuator using Terfenol-D

00

05

10

B (T)

800

1000

1200

1400

1600

Magnetostriction (ppm)

-100 -50 0 50 100

-10

-05

00

B (T)

H (kAm)

2 MPa

4 MPa

6 MPa

8 MPa

10 MPa

12 MPa

-100 -50 0 50 100

-200

0

200

400

600

Magnetostriction (ppm)

H (kAm)

2 MPa

4 MPa

6 MPa

8 MPa

10 MPa

12 MPa

600

700

800

900

1000

-4 -3 -2 -1 0 1 2 3 4

0

10

20

30

40

50

60

Displacement (m

icro meter)

I (A)

FIELD

9 kAm

12 kAm

16 kAm

20 kAm

24 kAm

38 kAm

-50 -40 -30 -20 -10 0 10 20 30 40 50

-100

0

100

200

300

400

500

L (PPM)

H (kAm)

9 kAm

12 kAm

16 kAm

20 kAm

24 kAm

38 kAm

Magnetostrictive displacement sensor

Hysteresis loops under

tensile stress σ

(a) Crystalline 68 NiFe

λs = +25 10-6

(b) crystalline pure Ni λs

= -35 10-6

Villari Effect ( Inverse of Joule Effect)

= -35 10-6

(c) amorphous Co-based

alloy

λs = -35 10-6

ϕσλ 2sin2

3sdotsdot= smeE

γ

Permeability depending on the stress

σλmicromicro

1

3

2

Y

J

so

s

r =

γ

Calculated magnetization curves under stress

Variation of magnetization curve by an applied

tensile force (Co-based amorphous alloy)

Alloy Requirement

Materials for magnetoelastic sensors

Why amorphous magnetic materials are important

Stress-strain curves of several materials

Coercivity and hardness of several materials

Principles of magnetoelastic sensors

Non-contact torque sensor

Principle of cross torductor torque

sensor and flux pattern of sensor

poles on the surface of a shaft

a) without and b)with torsional load

Equivalent magnetic circuit of

cross type torque sensor

Helices of principal tensile and compressive stress on the surface of

a shaft subjected to torsion [32] Correlated changes of permeability

are detected by four-branch yoke system with sensing coils 123

and 4 and a common excitation pole

Examples of torque sensors

Four-branch type torque sensor

heads Pole structures realized

by commercial multi-pole

ferrites 14 and 18 min in

diameter (diameter of sensor

h e a d 1 7 a n d 2 4 m m

respectively) respectively)

Principle of Ring Torductor torque transducer

(a b) Physical structure (c) evolution of the

shaft surface under the transducer poles A and BRing torductor for measuring

torque on ship propeller shafts

(shaft diameter ca 500 mm)

(Courtesy ASEA Brown

Boveri AG)

Principal designs of coaxial torque sensors

Schematic diagram of data processing

electronics of a torque sensor

Extensometer (a) Construction of strain sensing element using

amorphous ribbon wound core (b) configuration of lumped

windings

∆E effect of an amorphous FeNi-based

alloy (Fe40 Ni38 Mo4 B18) Hs saturation

field

Magnetically tunable delay line

Torque Sensors using Amorphous wire

Sixtus tonk효과(large Barkhausen효과)

Hysteresis loops of a Wiegand wire for different reset fields

Curie 온도 및Hopkinson효과

Relation between normalised

saturation polarisation and

normalised Curie temperature

Permeability of a Mn-Zn ferrite as

a function of temperature and field

strength

Conclusions

1) Magnetic sensor 는 자동차 공장자동화 항공우주 및 군사용으로많이 사용되고 있다

2) 새로운 소재개발은 자기센서의 성능개발에 직접적인 영향을 준다2) 새로운 소재개발은 자기센서의 성능개발에 직접적인 영향을 준다

3) 센서의 개발을 위해서는 다양한 전공지식이 요구된다

(물리학 재료공학 기계공학 전자공학)

4) 센서분야가 고부가가치를 창출하는 부품사업이다

5) 핵심부품을 생산하는 중소기업의 item으로도 적절하다

Arrangement for indirect noninvasive

current measurement using the

compensation principle An iron core as

represented in Figure 3-29 is held field

free by injection a current into a

compensating coil wound on the core

which offsets the field generated by the

current being measured The Hall effect

sensor in the air gap serves as a null

indicator

Circuit diagram for AC-power

measurement using a Hall effect

sensor

DC Power Measurement

Circuit diagram for DC-

power measurement using a

Hall effect sensor

Noncontact Position Sensing

Galvanomagnetic components for sensing the position of permanent magnets

and magnetically conductive materials

Current Sensor Based on Hall Sensor

and Magnetic Core for Hybrid Vehicle

KH Yeon1 SD Kim1 and D Son2 1Auto industry co14F Hanshin IT tower Guro Gu Seoul Korea2Hannam UniversityOjung dong 133 Daejeon Rep of Korea

i

Hall sensor

B

I

SB

ring core

B

I10

g

N

Bl S

micro

)( gtgtrmicro

gab core

Current Sensor Based on Hall

Sensor and Magnetic Core

Hall

Effect

Device

CurrentVoltage

applying for

Hall effect device

operation

Output

signals

Magnetic field

Occurred by

current measurement

Signal

process

circuits

Developed Current Sensor

Magnetic core

Hall sensor

PCB

25

30

35

40

45

50

Output voltage V

Current sensor(Open loop type)

Temp 25C

400A model

+400 ~ -400A

SD 000128

Linearity 003

Linearity of the sensor

Characteristics of the Current Sensors

1000A 10 V power supply

-500 -400 -300 -200 -100 0 100 200 300 400 500

00

05

10

15

20

Output voltage V

current A

Temperature 25Linearity 003

Measuring range -400A ~ +400A

1000A Electronic Load

-3

0

3

6

9

12

15

18

dB

Current sensor

DV2 PCB 24pF

40Aturns

Frequency bandwidth

Gain bandwidth 3 MHz

Current 10 A

Temperature 25

Frequency bandwidth 100 kHz

Sensor output voltage vs frequency

at applied current of 40 Aturns

1 10 100

-18

-15

-12

-9

-6

Frequency kHz 측정온도 25

주파수특성 30kHz 이상(3dB 기준)

측정전류 40Aturns(4A 10턴)

측정주파수 100Hz ~ 100kHz

Temperature 25Current 40Aturns

Frequency range 100 Hz ~ 100 kHz

What is Magnetoresistance

Magnetoresistance effect(AMR)

θθθ 2cos2

12sin12cos(

22 minusminus+∆asymp∆ xxxmx hhhRR

32 minusasymp∆ ρρ New effect GMR CMR and GMI

10 ge∆ ρρ

Two bridge configuration for

rotational angle measurement

measurement angle more than 180o

자동차 Engine Management System

Inductive and Eddy Current

Sensors Excited by Permanent Magnets

tNtU dd)( φsdotminus=

construction of an inductive

sensor (courtesy VDO Adolf sensor (courtesy VDO Adolf

Schindling AG)

1) constant socket

2) terminal package

3) permanent magnet

4) cap

5) soft magnetic core

6) coil

7) plate

8) blade connector

γγ

Sensor with yoke Change in the magnetic flux with

varying air gap Continuous lines

minimum air gap dashed lines

maximum air gap

C-shaped sensor

Sensor with radially

magnetized

permanent magnet

Signal Conditioning

Output voltage U of a DC-excited sensor with permanent

magnets when a single iron object passes by

Schematic electrical diagram of an inductive sensor

Linear Variable Differential Transformer

AC-Excited Sensors for Linear Movement

Principle of construction of an LVDT

Electrical circuit of an LVDT

tIMtNU dd dd sdotminus=sdotminus= φ

tIMtIMUUU dd dd 1212 sdotminussdot=minus=

tIMMU dd)( 12 sdotminus=

)(12 xMMMM =minus=

tIxMU dd)( sdot= tI

UxM

dd)( =

Signal Conditioning

power supply

carrier gen

autoampcontrol

LVDTcarrieramp

demod-ulator

phase

shifter

power supply

carrier gen

passivedemod-ulator

LVDTDCamp

Block diagram of a carrier amplifier system

Block diagram of a DC amplifier system

Variable Inductive Sensors

Principle of construction

of the VLP sensor

Principle of a bridge

circuit

lANL r 20 sdotsdotsdot= micromicro

21 BA UUU minus=

21)i(ii( 211 minus+sdot= LLLUU BA ωωω

)21))()((( minus∆minus+∆+∆+sdot= LLLLLLUU BA

)212)(( minus∆+sdot= LLLUU )212)(( minus∆+sdot= LLLUU BA

LLUU BA 21 ∆sdotsdot=

llLL ∆sdot=∆ d d

llLLUU BA ∆sdotsdot= d d)2(1

Applications and Properties

Principle of a construction of a force transducer

(courtesy Hottinger Baldwin Messtechnik)

Vibrationacceleration sensor

Signal Conditioning

Schematic electrical diagram of a force transducer connected with an

amplifier (courtesy Hottinger Baldwin Messtechnik GmbH)

Variable Gap Sensors

)( FeFe2

0 LLllANL micromicromicro +sdotsdot=

FeFe2

0max lANL sdotsdotsdot= micromicro

Construction of a variable gap sensor

Characteristic of a variable gap sensor

Construction of a differential

cross-anchor sensor

Output voltage U versus core

position x plusmn a limits of the

linear rage

Applications of differential cross-anchor sensors

AC-excited Sensors for Rotary Movements

Principle of construction of a synchro

α cos10 sdotsdot= UKU y

)120-( cos10 degsdotsdot= αUKU z

)240-( cos10 degsdotsdot= αUKU x

)120-( sin3100 degsdotsdotsdot=minus= αKUUUU yxyx

)240-( sin3100 degsdotsdotsdot=minus= αKUUUU zyzy

α sin3100 sdotsdotsdot=minus= KUUUU xzxz

Application to the Torque Sensor

Principle of construction of a torque-type synchro

Torque versus angular

difference

)( sin~ rt αα minussdotKM

)( cos~ rt1r αα minussdotUU

Principle of construction of a control-type sensor

Output voltage versus

angular difference

Principle of construction of a differential sychro

Eddy Current Sensors

tBE dd curl minus=JH = curl

0 div =BH(H)B sdot= micro

E(E)J sdot= σ

A B curl= A B curl=

tdd- A E =

)dd( tAJ minus= σ

tdd curl curl AA σmicro minus=

AA) σωmicro iminus= curl )(curl(1

AA) σωmicro i=∆)((1

Eddy Current Tachometer

Construction of a speedometer (courtesy VDO Adolf Schinding AG) 1) spindle 2) bearing

3) holding spring 4) iron yoke 5) eddy current cup 6) shaft of the magnet 7) support of

the magnet 8) temperature compensation 9) permanent magnet 10) torsion spring

Proximity Sensors

Schematic diagram of a proximity sensor

Output current of a proximity switch versus distance

Inductive Flowmeters

)( Btimessdot= υqF

EqF sdot=BE times=υ

)(ds Btimes== υEU )(ds Btimes== υEU

)( Bd timessdot= υU

Bsdotsdotsdot= υdKU

Development of magnetic phase detection

sensor for steam generator tube

Dirac Son1 Kwan-Sang Ryu2 Duck-Gun Park3

1Hannam University Daejeon Rep of Korea2Korea Research Institute of Standards and Science Daejeon Rep of Korea3KoreaAtomic Energy Research Institute Daejeon Rep of Korea

Introduction

The layout of pressurized water reactor (PWR) components

Primary side Secondary side (non-radioactive side)(radioactive side)

The Structure of SG(Steam Generator)(degradation mechanism)

Secondary SidePrimary Side

SCC

A B

A-B

Steam outlet

Anti-vibration

SCC

Fretting

Wall thinning

IGA

U-bend

In commercial power plants SG- height up to 21 m - weight up to 800 tons - 2~4 sets of SG were installed - SG can contain from 3000 to

16000 tubes each about 20 mmin diameter

Primary coolant outlet Primary coolant inlet

Anti-vibrationbars

Tubesupportplate

Tubesheet

IGA

SCC

Pitting

SCC

Inside Tubesheet

Top of Tubesheet

by SSHwang of KAERI

Denting

Sludge pile

in diameter

The SGT is made of nickel basedInconel alloy which is composed of 75 Ni 165Cr and 815Fe

-Degradation mechanism corrosion pitting denting inter granular attack

-Inspection Eddy current Testing(ECT)

Permeability Variation Clusters (PVC)

(Ferro-magnetic phase)

-005

000

005

010

015

m (emug)

1-1

-002

000

002

004

006

008

m (emug)

1-2

-1000 -500 0 500 1000

-015

-010

-005

H ( Am )

-1000 -500 0 500 1000

-006

-004

-002

H ( Am )

The hystresis loop in the fragment of PVC parts of Kori-1 retired SG tube

-004

-002

000

002

004

006

M (emug)

Inconel 600 tested at RT

under tensile stress

1 2 3

4 5 6

7 8 9-004

-002

000

002

004

006

M(emug)

Inconel 600 Heat treated at

602 oC under tensile stress

1 2 3

How can we detect magnetic phase

(PVC)selectively from the flaws in SGT

-3000 -2000 -1000 0 1000 2000 3000

-006

H (Oe)

7 8 9

10 11 12

-3000 -2000 -1000 0 1000 2000 3000

-006

-004

H(Oe)

4 5 6

7 8 9

The hysteresis loop of the tensile tested specimen at room temperature (a) and tensile tested at high temperature (b)

The magnetic phase can be created under the high temperature andpressure conditions which is correspond to the stress corrosion crackingin the SG tube in the NPP(Bruemmer SM Charlot LA amp Henager CH (1988) Corrosion 782)

Principle of ECT

If we can separate magnetic phase selectively from the

flaws using magnetic sensor the reliability of EC in SGT

inspection will be greatly enhanced

Structure of the permeability

sensor

Dimension and photograph of U-shape

sensing yoke

Design of Magnetic Sensor for PVC

sensor sensing yoke

Photograph of the completed sensor front side (above) and rear side (bottom)

R11R12

R10

R8

R6

R9

R13

R7

R14

C18

1 n

C17

C20

C21

D2

DIODE

SIN COS

-

+

U-2A

4

13

2

-

+

U-2B

75

6

8

-

+

U-3A

13

2

8

+5VC19

104

+5V

Schematic diagram of the sensor system

Electronic Circuit of Magnetic Sensor

R20

R

R21

R

-

+

U5AD797

3

26

74

U6

D1

S12

GND3

+VCC4VCC5

IN6

-VCC7

S28

C41

R13

R26

R18

R25

R2210 Ω

R16

R14

R17

10 k

R15

R27

R32

R28

R33

R29

R34

5 k

R30

C29

C37

104

C32473

C39473C40

104

C33

104

C21

104C23

104

C25

104

C26

104

C30

104

C31

104

C35

104

C36

104

C27

104

C28

104

C34

104

C38

104

D3

DIODE

L1

1

2

L2

1

2

L3

1

2

4

-

+

U-4A

4

13

2

-

+

U-4B

75

6

8

-

+

U-5A

4

13

2

-

+

U-5B

75

6

8

-

+

U-6A

4

13

2

-

+

U-6B

75

6

8

C22

104

-5V

+5V

+5V

+5V

+5V

+5V

+5V

U7

D1

S12

GND3

+VCC4

VCC5

IN6

-VCC7

S28

+5V

-5V

-5V

-5V

-5V

-5V

-5V

-5V

-5V

R19

R24

R

R23

R

C24

OUT(X)

OUT(Y)

R1

20 kR210 k

R3

20 kR410 k

C1

104

C8

104

REF43

OUT(X)

OUT(Y)

REF43

U2

+Vcc1

CH02

CH13

CH24

CH35

COMM6

SHDN7

Vref8

+Vcc9

GND10

GND11

DOUT12BUSY13DIN14CS15

DIN16

-

+

U-1A

13

2

8

-

+

U-1B

4

75

6

C410 uF

C5104

DOUT

C210uF

C6104

C3104

DCLK

C7104

DIN

C10

01uF

CS

BUSY

C14 10uF

J1

CON6

123456

D1

DIODE

R5

47K

C9

10uF

C1310uF

Y1

OSC

OUT3

GND2

VCC4

U3

RSTVPP1

GND10

VCC20

XTAL15

XTAL24

P10AIN012P11AIN113P1214P1315P1416P1517P1618P1719

P30RXD2

P31TXD3

P32INT06

P33INT17

P34T08

P35T19

P3711

U4

C1+1

C1-3

C2+4

C2-5

VCC16

GND15

V+2

V-6

R1OUT12

R2OUT9

T1IN11

T2IN10

R1IN13

R2IN8

T1OUT14

T2OUT7

C12 10uF

C16

01uF

C15 10uF

C11

01uF

-5V

+5V

+5V

+5V

+5V

+5V

+5V

+5V

RST

OSC

OSC

RST

DCLKCSDINBUSYDOUT

U1

IN2

GND

4

OUT6

TEMP3

TRIM5

-5V

+5V

Electronic circuit diagram of the magnetic sensor

Photograph of the completed measuring system data acquisition

software in PC and probe scanning system

Experimental Setup for Magnetic Sensor

Reference material Scanning System Software LabVIEW

Reference Material (1) Normal defects and PVCs

Longitudinal and transverse defects

Def W L D Remarks

1 02 500 0213 (20 ) Inner defects

2 02 500 0427 (40 )

3 02 500 0213 (20 )Outer defectsPVC(1018)4 02 500 0427 (40 )

5 02 500 0639 (60 )

6 02 500 0852 (80 )

7 02 500 0639 (60 ) Inner defects

8 02 500 0852 (80 )

- 1 and 2 are inner defects

- 345 and 6 are outer defects with PVC

- 7 and 8 are inner defects

PVC

PVC

Defect Defect

For longitudinal defects and PVC For circumferential defects and PVC

ECT is very difficult to detect circumferential defects

We can distinguish PVCs and defects and longitudinal and circumferential defects

Flux-gate Magnetometer

One core sensor Two core sensor

3-축 flux-gate Magnetometer의 계략도

Sensorpia Co

pro

cess

or(

AV

R)

Sensor 1

RS422

Interface

Mic

ro-p

roce

ssor(

AV

R)

Sensor 2

Sensor 3

Interface

조립된 마그네토미터의 사진

Sensorpia Co

Analog PCB

Digital PCB

Sensorpia Co선형도(linearity)

10

20

30

40

50

60

y-axis

Magnetometer Output (microT)

-60 -50 -40 -30 -20 -10 0 10 20 30 40 50 60

-60

-50

-40

-30

-20

-10

0

10

Y-axis y=099946 x+0015STD 106E-4

Magnetometer Output (

Applied Magnetic Field (microT)

마그네토미터의 noise 특성 Sensorpia Co

1

10

100

y-axis

Magnetometer noise (nT)

0 1 2 3 4 5 6

1E-4

1E-3

001

01

Magnetometer noise (nT)

Frequency (Hz)

Magnetometer for KoDSAT

-150 -100 -50 0 50 100 150

-15

-10

-5

0

5

10

15

Magnetic Moment (Am

2)

Current (mA)

After Thermal Cycle Test

Measured

Resistance 193 ohm

Photograph of Magnetic torquer

Photograph of KoDSAT

Photograph of

3-axis Fluxgate

Magnetometer

Photograph of Magnetic torquer

Application of magnetometer

Moon magnetic fieldmeasurement

Telescope with direction indication

Joule Effect (Magnetostriction)

ϕ2cosel

l=

∆

0=∆

+∆

+∆

b

b

a

a

l

l

Actuator using Terfenol-D

00

05

10

B (T)

800

1000

1200

1400

1600

Magnetostriction (ppm)

-100 -50 0 50 100

-10

-05

00

B (T)

H (kAm)

2 MPa

4 MPa

6 MPa

8 MPa

10 MPa

12 MPa

-100 -50 0 50 100

-200

0

200

400

600

Magnetostriction (ppm)

H (kAm)

2 MPa

4 MPa

6 MPa

8 MPa

10 MPa

12 MPa

600

700

800

900

1000

-4 -3 -2 -1 0 1 2 3 4

0

10

20

30

40

50

60

Displacement (m

icro meter)

I (A)

FIELD

9 kAm

12 kAm

16 kAm

20 kAm

24 kAm

38 kAm

-50 -40 -30 -20 -10 0 10 20 30 40 50

-100

0

100

200

300

400

500

L (PPM)

H (kAm)

9 kAm

12 kAm

16 kAm

20 kAm

24 kAm

38 kAm

Magnetostrictive displacement sensor

Hysteresis loops under

tensile stress σ

(a) Crystalline 68 NiFe

λs = +25 10-6

(b) crystalline pure Ni λs

= -35 10-6

Villari Effect ( Inverse of Joule Effect)

= -35 10-6

(c) amorphous Co-based

alloy

λs = -35 10-6

ϕσλ 2sin2

3sdotsdot= smeE

γ

Permeability depending on the stress

σλmicromicro

1

3

2

Y

J

so

s

r =

γ

Calculated magnetization curves under stress

Variation of magnetization curve by an applied

tensile force (Co-based amorphous alloy)

Alloy Requirement

Materials for magnetoelastic sensors

Why amorphous magnetic materials are important

Stress-strain curves of several materials

Coercivity and hardness of several materials

Principles of magnetoelastic sensors

Non-contact torque sensor

Principle of cross torductor torque

sensor and flux pattern of sensor

poles on the surface of a shaft

a) without and b)with torsional load

Equivalent magnetic circuit of

cross type torque sensor

Helices of principal tensile and compressive stress on the surface of

a shaft subjected to torsion [32] Correlated changes of permeability

are detected by four-branch yoke system with sensing coils 123

and 4 and a common excitation pole

Examples of torque sensors

Four-branch type torque sensor

heads Pole structures realized

by commercial multi-pole

ferrites 14 and 18 min in

diameter (diameter of sensor

h e a d 1 7 a n d 2 4 m m

respectively) respectively)

Principle of Ring Torductor torque transducer

(a b) Physical structure (c) evolution of the

shaft surface under the transducer poles A and BRing torductor for measuring

torque on ship propeller shafts

(shaft diameter ca 500 mm)

(Courtesy ASEA Brown

Boveri AG)

Principal designs of coaxial torque sensors

Schematic diagram of data processing

electronics of a torque sensor

Extensometer (a) Construction of strain sensing element using

amorphous ribbon wound core (b) configuration of lumped

windings

∆E effect of an amorphous FeNi-based

alloy (Fe40 Ni38 Mo4 B18) Hs saturation

field

Magnetically tunable delay line

Torque Sensors using Amorphous wire

Sixtus tonk효과(large Barkhausen효과)

Hysteresis loops of a Wiegand wire for different reset fields

Curie 온도 및Hopkinson효과

Relation between normalised

saturation polarisation and

normalised Curie temperature

Permeability of a Mn-Zn ferrite as

a function of temperature and field

strength

Conclusions

1) Magnetic sensor 는 자동차 공장자동화 항공우주 및 군사용으로많이 사용되고 있다

2) 새로운 소재개발은 자기센서의 성능개발에 직접적인 영향을 준다2) 새로운 소재개발은 자기센서의 성능개발에 직접적인 영향을 준다

3) 센서의 개발을 위해서는 다양한 전공지식이 요구된다

(물리학 재료공학 기계공학 전자공학)

4) 센서분야가 고부가가치를 창출하는 부품사업이다

5) 핵심부품을 생산하는 중소기업의 item으로도 적절하다

DC Power Measurement

Circuit diagram for DC-

power measurement using a

Hall effect sensor

Noncontact Position Sensing

Galvanomagnetic components for sensing the position of permanent magnets

and magnetically conductive materials

Current Sensor Based on Hall Sensor

and Magnetic Core for Hybrid Vehicle

KH Yeon1 SD Kim1 and D Son2 1Auto industry co14F Hanshin IT tower Guro Gu Seoul Korea2Hannam UniversityOjung dong 133 Daejeon Rep of Korea

i

Hall sensor

B

I

SB

ring core

B

I10

g

N

Bl S

micro

)( gtgtrmicro

gab core

Current Sensor Based on Hall

Sensor and Magnetic Core

Hall

Effect

Device

CurrentVoltage

applying for

Hall effect device

operation

Output

signals

Magnetic field

Occurred by

current measurement

Signal

process

circuits

Developed Current Sensor

Magnetic core

Hall sensor

PCB

25

30

35

40

45

50

Output voltage V

Current sensor(Open loop type)

Temp 25C

400A model

+400 ~ -400A

SD 000128

Linearity 003

Linearity of the sensor

Characteristics of the Current Sensors

1000A 10 V power supply

-500 -400 -300 -200 -100 0 100 200 300 400 500

00

05

10

15

20

Output voltage V

current A

Temperature 25Linearity 003

Measuring range -400A ~ +400A

1000A Electronic Load

-3

0

3

6

9

12

15

18

dB

Current sensor

DV2 PCB 24pF

40Aturns

Frequency bandwidth

Gain bandwidth 3 MHz

Current 10 A

Temperature 25

Frequency bandwidth 100 kHz

Sensor output voltage vs frequency

at applied current of 40 Aturns

1 10 100

-18

-15

-12

-9

-6

Frequency kHz 측정온도 25

주파수특성 30kHz 이상(3dB 기준)

측정전류 40Aturns(4A 10턴)

측정주파수 100Hz ~ 100kHz

Temperature 25Current 40Aturns

Frequency range 100 Hz ~ 100 kHz

What is Magnetoresistance

Magnetoresistance effect(AMR)

θθθ 2cos2

12sin12cos(

22 minusminus+∆asymp∆ xxxmx hhhRR

32 minusasymp∆ ρρ New effect GMR CMR and GMI

10 ge∆ ρρ

Two bridge configuration for

rotational angle measurement

measurement angle more than 180o

자동차 Engine Management System

Inductive and Eddy Current

Sensors Excited by Permanent Magnets

tNtU dd)( φsdotminus=

construction of an inductive

sensor (courtesy VDO Adolf sensor (courtesy VDO Adolf

Schindling AG)

1) constant socket

2) terminal package

3) permanent magnet

4) cap

5) soft magnetic core

6) coil

7) plate

8) blade connector

γγ

Sensor with yoke Change in the magnetic flux with

varying air gap Continuous lines

minimum air gap dashed lines

maximum air gap

C-shaped sensor

Sensor with radially

magnetized

permanent magnet

Signal Conditioning

Output voltage U of a DC-excited sensor with permanent

magnets when a single iron object passes by

Schematic electrical diagram of an inductive sensor

Linear Variable Differential Transformer

AC-Excited Sensors for Linear Movement

Principle of construction of an LVDT

Electrical circuit of an LVDT

tIMtNU dd dd sdotminus=sdotminus= φ

tIMtIMUUU dd dd 1212 sdotminussdot=minus=

tIMMU dd)( 12 sdotminus=

)(12 xMMMM =minus=

tIxMU dd)( sdot= tI

UxM

dd)( =

Signal Conditioning

power supply

carrier gen

autoampcontrol

LVDTcarrieramp

demod-ulator

phase

shifter

power supply

carrier gen

passivedemod-ulator

LVDTDCamp

Block diagram of a carrier amplifier system

Block diagram of a DC amplifier system

Variable Inductive Sensors

Principle of construction

of the VLP sensor

Principle of a bridge

circuit

lANL r 20 sdotsdotsdot= micromicro

21 BA UUU minus=

21)i(ii( 211 minus+sdot= LLLUU BA ωωω

)21))()((( minus∆minus+∆+∆+sdot= LLLLLLUU BA

)212)(( minus∆+sdot= LLLUU )212)(( minus∆+sdot= LLLUU BA

LLUU BA 21 ∆sdotsdot=

llLL ∆sdot=∆ d d

llLLUU BA ∆sdotsdot= d d)2(1

Applications and Properties

Principle of a construction of a force transducer

(courtesy Hottinger Baldwin Messtechnik)

Vibrationacceleration sensor

Signal Conditioning

Schematic electrical diagram of a force transducer connected with an

amplifier (courtesy Hottinger Baldwin Messtechnik GmbH)

Variable Gap Sensors

)( FeFe2

0 LLllANL micromicromicro +sdotsdot=

FeFe2

0max lANL sdotsdotsdot= micromicro

Construction of a variable gap sensor

Characteristic of a variable gap sensor

Construction of a differential

cross-anchor sensor

Output voltage U versus core

position x plusmn a limits of the

linear rage

Applications of differential cross-anchor sensors

AC-excited Sensors for Rotary Movements

Principle of construction of a synchro

α cos10 sdotsdot= UKU y

)120-( cos10 degsdotsdot= αUKU z

)240-( cos10 degsdotsdot= αUKU x

)120-( sin3100 degsdotsdotsdot=minus= αKUUUU yxyx

)240-( sin3100 degsdotsdotsdot=minus= αKUUUU zyzy

α sin3100 sdotsdotsdot=minus= KUUUU xzxz

Application to the Torque Sensor

Principle of construction of a torque-type synchro

Torque versus angular

difference

)( sin~ rt αα minussdotKM

)( cos~ rt1r αα minussdotUU

Principle of construction of a control-type sensor

Output voltage versus

angular difference

Principle of construction of a differential sychro

Eddy Current Sensors

tBE dd curl minus=JH = curl

0 div =BH(H)B sdot= micro

E(E)J sdot= σ

A B curl= A B curl=

tdd- A E =

)dd( tAJ minus= σ

tdd curl curl AA σmicro minus=

AA) σωmicro iminus= curl )(curl(1

AA) σωmicro i=∆)((1

Eddy Current Tachometer

Construction of a speedometer (courtesy VDO Adolf Schinding AG) 1) spindle 2) bearing

3) holding spring 4) iron yoke 5) eddy current cup 6) shaft of the magnet 7) support of

the magnet 8) temperature compensation 9) permanent magnet 10) torsion spring

Proximity Sensors

Schematic diagram of a proximity sensor

Output current of a proximity switch versus distance

Inductive Flowmeters

)( Btimessdot= υqF

EqF sdot=BE times=υ

)(ds Btimes== υEU )(ds Btimes== υEU

)( Bd timessdot= υU

Bsdotsdotsdot= υdKU

Development of magnetic phase detection

sensor for steam generator tube

Dirac Son1 Kwan-Sang Ryu2 Duck-Gun Park3

1Hannam University Daejeon Rep of Korea2Korea Research Institute of Standards and Science Daejeon Rep of Korea3KoreaAtomic Energy Research Institute Daejeon Rep of Korea

Introduction

The layout of pressurized water reactor (PWR) components

Primary side Secondary side (non-radioactive side)(radioactive side)

The Structure of SG(Steam Generator)(degradation mechanism)

Secondary SidePrimary Side

SCC

A B

A-B

Steam outlet

Anti-vibration

SCC

Fretting

Wall thinning

IGA

U-bend

In commercial power plants SG- height up to 21 m - weight up to 800 tons - 2~4 sets of SG were installed - SG can contain from 3000 to

16000 tubes each about 20 mmin diameter

Primary coolant outlet Primary coolant inlet

Anti-vibrationbars

Tubesupportplate

Tubesheet

IGA

SCC

Pitting

SCC

Inside Tubesheet

Top of Tubesheet

by SSHwang of KAERI

Denting

Sludge pile

in diameter

The SGT is made of nickel basedInconel alloy which is composed of 75 Ni 165Cr and 815Fe

-Degradation mechanism corrosion pitting denting inter granular attack

-Inspection Eddy current Testing(ECT)

Permeability Variation Clusters (PVC)

(Ferro-magnetic phase)

-005

000

005

010

015

m (emug)

1-1

-002

000

002

004

006

008

m (emug)

1-2

-1000 -500 0 500 1000

-015

-010

-005

H ( Am )

-1000 -500 0 500 1000

-006

-004

-002

H ( Am )

The hystresis loop in the fragment of PVC parts of Kori-1 retired SG tube

-004

-002

000

002

004

006

M (emug)

Inconel 600 tested at RT

under tensile stress

1 2 3

4 5 6

7 8 9-004

-002

000

002

004

006

M(emug)

Inconel 600 Heat treated at

602 oC under tensile stress

1 2 3

How can we detect magnetic phase

(PVC)selectively from the flaws in SGT

-3000 -2000 -1000 0 1000 2000 3000

-006

H (Oe)

7 8 9

10 11 12

-3000 -2000 -1000 0 1000 2000 3000

-006

-004

H(Oe)

4 5 6

7 8 9

The hysteresis loop of the tensile tested specimen at room temperature (a) and tensile tested at high temperature (b)

The magnetic phase can be created under the high temperature andpressure conditions which is correspond to the stress corrosion crackingin the SG tube in the NPP(Bruemmer SM Charlot LA amp Henager CH (1988) Corrosion 782)

Principle of ECT

If we can separate magnetic phase selectively from the

flaws using magnetic sensor the reliability of EC in SGT

inspection will be greatly enhanced

Structure of the permeability

sensor

Dimension and photograph of U-shape

sensing yoke

Design of Magnetic Sensor for PVC

sensor sensing yoke

Photograph of the completed sensor front side (above) and rear side (bottom)

R11R12

R10

R8

R6

R9

R13

R7

R14

C18

1 n

C17

C20

C21

D2

DIODE

SIN COS

-

+

U-2A

4

13

2

-

+

U-2B

75

6

8

-

+

U-3A

13

2

8

+5VC19

104

+5V

Schematic diagram of the sensor system

Electronic Circuit of Magnetic Sensor

R20

R

R21

R

-

+

U5AD797

3

26

74

U6

D1

S12

GND3

+VCC4VCC5

IN6

-VCC7

S28

C41

R13

R26

R18

R25

R2210 Ω

R16

R14

R17

10 k

R15

R27

R32

R28

R33

R29

R34

5 k

R30

C29

C37

104

C32473

C39473C40

104

C33

104

C21

104C23

104

C25

104

C26

104

C30

104

C31

104

C35

104

C36

104

C27

104

C28

104

C34

104

C38

104

D3

DIODE

L1

1

2

L2

1

2

L3

1

2

4

-

+

U-4A

4

13

2

-

+

U-4B

75

6

8

-

+

U-5A

4

13

2

-

+

U-5B

75

6

8

-

+

U-6A

4

13

2

-

+

U-6B

75

6

8

C22

104

-5V

+5V

+5V

+5V

+5V

+5V

+5V

U7

D1

S12

GND3

+VCC4

VCC5

IN6

-VCC7

S28

+5V

-5V

-5V

-5V

-5V

-5V

-5V

-5V

-5V

R19

R24

R

R23

R

C24

OUT(X)

OUT(Y)

R1

20 kR210 k

R3

20 kR410 k

C1

104

C8

104

REF43

OUT(X)

OUT(Y)

REF43

U2

+Vcc1

CH02

CH13

CH24

CH35

COMM6

SHDN7

Vref8

+Vcc9

GND10

GND11

DOUT12BUSY13DIN14CS15

DIN16

-

+

U-1A

13

2

8

-

+

U-1B

4

75

6

C410 uF

C5104

DOUT

C210uF

C6104

C3104

DCLK

C7104

DIN

C10

01uF

CS

BUSY

C14 10uF

J1

CON6

123456

D1

DIODE

R5

47K

C9

10uF

C1310uF

Y1

OSC

OUT3

GND2

VCC4

U3

RSTVPP1

GND10

VCC20

XTAL15

XTAL24

P10AIN012P11AIN113P1214P1315P1416P1517P1618P1719

P30RXD2

P31TXD3

P32INT06

P33INT17

P34T08

P35T19

P3711

U4

C1+1

C1-3

C2+4

C2-5

VCC16

GND15

V+2

V-6

R1OUT12

R2OUT9

T1IN11

T2IN10

R1IN13

R2IN8

T1OUT14

T2OUT7

C12 10uF

C16

01uF

C15 10uF

C11

01uF

-5V

+5V

+5V

+5V

+5V

+5V

+5V

+5V

RST

OSC

OSC

RST

DCLKCSDINBUSYDOUT

U1

IN2

GND

4

OUT6

TEMP3

TRIM5

-5V

+5V

Electronic circuit diagram of the magnetic sensor

Photograph of the completed measuring system data acquisition

software in PC and probe scanning system

Experimental Setup for Magnetic Sensor

Reference material Scanning System Software LabVIEW

Reference Material (1) Normal defects and PVCs

Longitudinal and transverse defects

Def W L D Remarks

1 02 500 0213 (20 ) Inner defects

2 02 500 0427 (40 )

3 02 500 0213 (20 )Outer defectsPVC(1018)4 02 500 0427 (40 )

5 02 500 0639 (60 )

6 02 500 0852 (80 )

7 02 500 0639 (60 ) Inner defects

8 02 500 0852 (80 )

- 1 and 2 are inner defects

- 345 and 6 are outer defects with PVC

- 7 and 8 are inner defects

PVC

PVC

Defect Defect

For longitudinal defects and PVC For circumferential defects and PVC

ECT is very difficult to detect circumferential defects

We can distinguish PVCs and defects and longitudinal and circumferential defects

Flux-gate Magnetometer

One core sensor Two core sensor

3-축 flux-gate Magnetometer의 계략도

Sensorpia Co

pro

cess

or(

AV

R)

Sensor 1

RS422

Interface

Mic

ro-p

roce

ssor(

AV

R)

Sensor 2

Sensor 3

Interface

조립된 마그네토미터의 사진

Sensorpia Co

Analog PCB

Digital PCB

Sensorpia Co선형도(linearity)

10

20

30

40

50

60

y-axis

Magnetometer Output (microT)

-60 -50 -40 -30 -20 -10 0 10 20 30 40 50 60

-60

-50

-40

-30

-20

-10

0

10

Y-axis y=099946 x+0015STD 106E-4

Magnetometer Output (

Applied Magnetic Field (microT)

마그네토미터의 noise 특성 Sensorpia Co

1

10

100

y-axis

Magnetometer noise (nT)

0 1 2 3 4 5 6

1E-4

1E-3

001

01

Magnetometer noise (nT)

Frequency (Hz)

Magnetometer for KoDSAT

-150 -100 -50 0 50 100 150

-15

-10

-5

0

5

10

15

Magnetic Moment (Am

2)

Current (mA)

After Thermal Cycle Test

Measured

Resistance 193 ohm

Photograph of Magnetic torquer

Photograph of KoDSAT

Photograph of

3-axis Fluxgate

Magnetometer

Photograph of Magnetic torquer

Application of magnetometer

Moon magnetic fieldmeasurement

Telescope with direction indication

Joule Effect (Magnetostriction)

ϕ2cosel

l=

∆

0=∆

+∆

+∆

b

b

a

a

l

l

Actuator using Terfenol-D

00

05

10

B (T)

800

1000

1200

1400

1600

Magnetostriction (ppm)

-100 -50 0 50 100

-10

-05

00

B (T)

H (kAm)

2 MPa

4 MPa

6 MPa

8 MPa

10 MPa

12 MPa

-100 -50 0 50 100

-200

0

200

400

600

Magnetostriction (ppm)

H (kAm)

2 MPa

4 MPa

6 MPa

8 MPa

10 MPa

12 MPa

600

700

800

900

1000

-4 -3 -2 -1 0 1 2 3 4

0

10

20

30

40

50

60

Displacement (m

icro meter)

I (A)

FIELD

9 kAm

12 kAm

16 kAm

20 kAm

24 kAm

38 kAm

-50 -40 -30 -20 -10 0 10 20 30 40 50

-100

0

100

200

300

400

500

L (PPM)

H (kAm)

9 kAm

12 kAm

16 kAm

20 kAm

24 kAm

38 kAm

Magnetostrictive displacement sensor

Hysteresis loops under

tensile stress σ

(a) Crystalline 68 NiFe

λs = +25 10-6

(b) crystalline pure Ni λs

= -35 10-6

Villari Effect ( Inverse of Joule Effect)

= -35 10-6

(c) amorphous Co-based

alloy

λs = -35 10-6

ϕσλ 2sin2

3sdotsdot= smeE

γ

Permeability depending on the stress

σλmicromicro

1

3

2

Y

J

so

s

r =

γ

Calculated magnetization curves under stress

Variation of magnetization curve by an applied

tensile force (Co-based amorphous alloy)

Alloy Requirement

Materials for magnetoelastic sensors

Why amorphous magnetic materials are important

Stress-strain curves of several materials

Coercivity and hardness of several materials

Principles of magnetoelastic sensors

Non-contact torque sensor

Principle of cross torductor torque

sensor and flux pattern of sensor

poles on the surface of a shaft

a) without and b)with torsional load

Equivalent magnetic circuit of

cross type torque sensor

Helices of principal tensile and compressive stress on the surface of

a shaft subjected to torsion [32] Correlated changes of permeability

are detected by four-branch yoke system with sensing coils 123

and 4 and a common excitation pole

Examples of torque sensors

Four-branch type torque sensor

heads Pole structures realized

by commercial multi-pole

ferrites 14 and 18 min in

diameter (diameter of sensor

h e a d 1 7 a n d 2 4 m m

respectively) respectively)

Principle of Ring Torductor torque transducer

(a b) Physical structure (c) evolution of the

shaft surface under the transducer poles A and BRing torductor for measuring

torque on ship propeller shafts

(shaft diameter ca 500 mm)

(Courtesy ASEA Brown

Boveri AG)

Principal designs of coaxial torque sensors

Schematic diagram of data processing

electronics of a torque sensor

Extensometer (a) Construction of strain sensing element using

amorphous ribbon wound core (b) configuration of lumped

windings

∆E effect of an amorphous FeNi-based

alloy (Fe40 Ni38 Mo4 B18) Hs saturation

field

Magnetically tunable delay line

Torque Sensors using Amorphous wire

Sixtus tonk효과(large Barkhausen효과)

Hysteresis loops of a Wiegand wire for different reset fields

Curie 온도 및Hopkinson효과

Relation between normalised

saturation polarisation and

normalised Curie temperature

Permeability of a Mn-Zn ferrite as

a function of temperature and field

strength

Conclusions

1) Magnetic sensor 는 자동차 공장자동화 항공우주 및 군사용으로많이 사용되고 있다

2) 새로운 소재개발은 자기센서의 성능개발에 직접적인 영향을 준다2) 새로운 소재개발은 자기센서의 성능개발에 직접적인 영향을 준다

3) 센서의 개발을 위해서는 다양한 전공지식이 요구된다

(물리학 재료공학 기계공학 전자공학)

4) 센서분야가 고부가가치를 창출하는 부품사업이다

5) 핵심부품을 생산하는 중소기업의 item으로도 적절하다

Noncontact Position Sensing

Galvanomagnetic components for sensing the position of permanent magnets

and magnetically conductive materials

Current Sensor Based on Hall Sensor

and Magnetic Core for Hybrid Vehicle

KH Yeon1 SD Kim1 and D Son2 1Auto industry co14F Hanshin IT tower Guro Gu Seoul Korea2Hannam UniversityOjung dong 133 Daejeon Rep of Korea

i

Hall sensor

B

I

SB

ring core

B

I10

g

N

Bl S

micro

)( gtgtrmicro

gab core

Current Sensor Based on Hall

Sensor and Magnetic Core

Hall

Effect

Device

CurrentVoltage

applying for

Hall effect device

operation

Output

signals

Magnetic field

Occurred by

current measurement

Signal

process

circuits

Developed Current Sensor

Magnetic core

Hall sensor

PCB

25

30

35

40

45

50

Output voltage V

Current sensor(Open loop type)

Temp 25C

400A model

+400 ~ -400A

SD 000128

Linearity 003

Linearity of the sensor

Characteristics of the Current Sensors

1000A 10 V power supply

-500 -400 -300 -200 -100 0 100 200 300 400 500

00

05

10

15

20

Output voltage V

current A

Temperature 25Linearity 003

Measuring range -400A ~ +400A

1000A Electronic Load

-3

0

3

6

9

12

15

18

dB

Current sensor

DV2 PCB 24pF

40Aturns

Frequency bandwidth

Gain bandwidth 3 MHz

Current 10 A

Temperature 25

Frequency bandwidth 100 kHz

Sensor output voltage vs frequency

at applied current of 40 Aturns

1 10 100

-18

-15

-12

-9

-6

Frequency kHz 측정온도 25

주파수특성 30kHz 이상(3dB 기준)

측정전류 40Aturns(4A 10턴)

측정주파수 100Hz ~ 100kHz

Temperature 25Current 40Aturns

Frequency range 100 Hz ~ 100 kHz

What is Magnetoresistance

Magnetoresistance effect(AMR)

θθθ 2cos2

12sin12cos(

22 minusminus+∆asymp∆ xxxmx hhhRR

32 minusasymp∆ ρρ New effect GMR CMR and GMI

10 ge∆ ρρ

Two bridge configuration for

rotational angle measurement

measurement angle more than 180o

자동차 Engine Management System

Inductive and Eddy Current

Sensors Excited by Permanent Magnets

tNtU dd)( φsdotminus=

construction of an inductive

sensor (courtesy VDO Adolf sensor (courtesy VDO Adolf

Schindling AG)

1) constant socket

2) terminal package

3) permanent magnet

4) cap

5) soft magnetic core

6) coil

7) plate

8) blade connector

γγ

Sensor with yoke Change in the magnetic flux with

varying air gap Continuous lines

minimum air gap dashed lines

maximum air gap

C-shaped sensor

Sensor with radially

magnetized

permanent magnet

Signal Conditioning

Output voltage U of a DC-excited sensor with permanent

magnets when a single iron object passes by

Schematic electrical diagram of an inductive sensor

Linear Variable Differential Transformer

AC-Excited Sensors for Linear Movement

Principle of construction of an LVDT

Electrical circuit of an LVDT

tIMtNU dd dd sdotminus=sdotminus= φ

tIMtIMUUU dd dd 1212 sdotminussdot=minus=

tIMMU dd)( 12 sdotminus=

)(12 xMMMM =minus=

tIxMU dd)( sdot= tI

UxM

dd)( =

Signal Conditioning

power supply

carrier gen

autoampcontrol

LVDTcarrieramp

demod-ulator

phase

shifter

power supply

carrier gen

passivedemod-ulator

LVDTDCamp

Block diagram of a carrier amplifier system

Block diagram of a DC amplifier system

Variable Inductive Sensors

Principle of construction

of the VLP sensor

Principle of a bridge

circuit

lANL r 20 sdotsdotsdot= micromicro

21 BA UUU minus=

21)i(ii( 211 minus+sdot= LLLUU BA ωωω

)21))()((( minus∆minus+∆+∆+sdot= LLLLLLUU BA

)212)(( minus∆+sdot= LLLUU )212)(( minus∆+sdot= LLLUU BA

LLUU BA 21 ∆sdotsdot=

llLL ∆sdot=∆ d d

llLLUU BA ∆sdotsdot= d d)2(1

Applications and Properties

Principle of a construction of a force transducer

(courtesy Hottinger Baldwin Messtechnik)

Vibrationacceleration sensor

Signal Conditioning

Schematic electrical diagram of a force transducer connected with an

amplifier (courtesy Hottinger Baldwin Messtechnik GmbH)

Variable Gap Sensors

)( FeFe2

0 LLllANL micromicromicro +sdotsdot=

FeFe2

0max lANL sdotsdotsdot= micromicro

Construction of a variable gap sensor

Characteristic of a variable gap sensor

Construction of a differential

cross-anchor sensor

Output voltage U versus core

position x plusmn a limits of the

linear rage

Applications of differential cross-anchor sensors

AC-excited Sensors for Rotary Movements

Principle of construction of a synchro

α cos10 sdotsdot= UKU y

)120-( cos10 degsdotsdot= αUKU z

)240-( cos10 degsdotsdot= αUKU x

)120-( sin3100 degsdotsdotsdot=minus= αKUUUU yxyx

)240-( sin3100 degsdotsdotsdot=minus= αKUUUU zyzy

α sin3100 sdotsdotsdot=minus= KUUUU xzxz

Application to the Torque Sensor

Principle of construction of a torque-type synchro

Torque versus angular

difference

)( sin~ rt αα minussdotKM

)( cos~ rt1r αα minussdotUU

Principle of construction of a control-type sensor

Output voltage versus

angular difference

Principle of construction of a differential sychro

Eddy Current Sensors

tBE dd curl minus=JH = curl

0 div =BH(H)B sdot= micro

E(E)J sdot= σ

A B curl= A B curl=

tdd- A E =

)dd( tAJ minus= σ

tdd curl curl AA σmicro minus=

AA) σωmicro iminus= curl )(curl(1

AA) σωmicro i=∆)((1

Eddy Current Tachometer

Construction of a speedometer (courtesy VDO Adolf Schinding AG) 1) spindle 2) bearing

3) holding spring 4) iron yoke 5) eddy current cup 6) shaft of the magnet 7) support of

the magnet 8) temperature compensation 9) permanent magnet 10) torsion spring

Proximity Sensors

Schematic diagram of a proximity sensor

Output current of a proximity switch versus distance

Inductive Flowmeters

)( Btimessdot= υqF

EqF sdot=BE times=υ

)(ds Btimes== υEU )(ds Btimes== υEU

)( Bd timessdot= υU

Bsdotsdotsdot= υdKU

Development of magnetic phase detection

sensor for steam generator tube

Dirac Son1 Kwan-Sang Ryu2 Duck-Gun Park3

1Hannam University Daejeon Rep of Korea2Korea Research Institute of Standards and Science Daejeon Rep of Korea3KoreaAtomic Energy Research Institute Daejeon Rep of Korea

Introduction

The layout of pressurized water reactor (PWR) components

Primary side Secondary side (non-radioactive side)(radioactive side)

The Structure of SG(Steam Generator)(degradation mechanism)

Secondary SidePrimary Side

SCC

A B

A-B

Steam outlet

Anti-vibration

SCC

Fretting

Wall thinning

IGA

U-bend

In commercial power plants SG- height up to 21 m - weight up to 800 tons - 2~4 sets of SG were installed - SG can contain from 3000 to

16000 tubes each about 20 mmin diameter

Primary coolant outlet Primary coolant inlet

Anti-vibrationbars

Tubesupportplate

Tubesheet

IGA

SCC

Pitting

SCC

Inside Tubesheet

Top of Tubesheet

by SSHwang of KAERI

Denting

Sludge pile

in diameter

The SGT is made of nickel basedInconel alloy which is composed of 75 Ni 165Cr and 815Fe

-Degradation mechanism corrosion pitting denting inter granular attack

-Inspection Eddy current Testing(ECT)

Permeability Variation Clusters (PVC)

(Ferro-magnetic phase)

-005

000

005

010

015

m (emug)

1-1

-002

000

002

004

006

008

m (emug)

1-2

-1000 -500 0 500 1000

-015

-010

-005

H ( Am )

-1000 -500 0 500 1000

-006

-004

-002

H ( Am )

The hystresis loop in the fragment of PVC parts of Kori-1 retired SG tube

-004

-002

000

002

004

006

M (emug)

Inconel 600 tested at RT

under tensile stress

1 2 3

4 5 6

7 8 9-004

-002

000

002

004

006

M(emug)

Inconel 600 Heat treated at

602 oC under tensile stress

1 2 3

How can we detect magnetic phase

(PVC)selectively from the flaws in SGT

-3000 -2000 -1000 0 1000 2000 3000

-006

H (Oe)

7 8 9

10 11 12

-3000 -2000 -1000 0 1000 2000 3000

-006

-004

H(Oe)

4 5 6

7 8 9

The hysteresis loop of the tensile tested specimen at room temperature (a) and tensile tested at high temperature (b)

The magnetic phase can be created under the high temperature andpressure conditions which is correspond to the stress corrosion crackingin the SG tube in the NPP(Bruemmer SM Charlot LA amp Henager CH (1988) Corrosion 782)

Principle of ECT

If we can separate magnetic phase selectively from the

flaws using magnetic sensor the reliability of EC in SGT

inspection will be greatly enhanced

Structure of the permeability

sensor

Dimension and photograph of U-shape

sensing yoke

Design of Magnetic Sensor for PVC

sensor sensing yoke

Photograph of the completed sensor front side (above) and rear side (bottom)

R11R12

R10

R8

R6

R9

R13

R7

R14

C18

1 n

C17

C20

C21

D2

DIODE

SIN COS

-

+

U-2A

4

13

2

-

+

U-2B

75

6

8

-

+

U-3A

13

2

8

+5VC19

104

+5V

Schematic diagram of the sensor system

Electronic Circuit of Magnetic Sensor

R20

R

R21

R

-

+

U5AD797

3

26

74

U6

D1

S12

GND3

+VCC4VCC5

IN6

-VCC7

S28

C41

R13

R26

R18

R25

R2210 Ω

R16

R14

R17

10 k

R15

R27

R32

R28

R33

R29

R34

5 k

R30

C29

C37

104

C32473

C39473C40

104

C33

104

C21

104C23

104

C25

104

C26

104

C30

104

C31

104

C35

104

C36

104

C27

104

C28

104

C34

104

C38

104

D3

DIODE

L1

1

2

L2

1

2

L3

1

2

4

-

+

U-4A

4

13

2

-

+

U-4B

75

6

8

-

+

U-5A

4

13

2

-

+

U-5B

75

6

8

-

+

U-6A

4

13

2

-

+

U-6B

75

6

8

C22

104

-5V

+5V

+5V

+5V

+5V

+5V

+5V

U7

D1

S12

GND3

+VCC4

VCC5

IN6

-VCC7

S28

+5V

-5V

-5V

-5V

-5V

-5V

-5V

-5V

-5V

R19

R24

R

R23

R

C24

OUT(X)

OUT(Y)

R1

20 kR210 k

R3

20 kR410 k

C1

104

C8

104

REF43

OUT(X)

OUT(Y)

REF43

U2

+Vcc1

CH02

CH13

CH24

CH35

COMM6

SHDN7

Vref8

+Vcc9

GND10

GND11

DOUT12BUSY13DIN14CS15

DIN16

-

+

U-1A

13

2

8

-

+

U-1B

4

75

6

C410 uF

C5104

DOUT

C210uF

C6104

C3104

DCLK

C7104

DIN

C10

01uF

CS

BUSY

C14 10uF

J1

CON6

123456

D1

DIODE

R5

47K

C9

10uF

C1310uF

Y1

OSC

OUT3

GND2

VCC4

U3

RSTVPP1

GND10

VCC20

XTAL15

XTAL24

P10AIN012P11AIN113P1214P1315P1416P1517P1618P1719

P30RXD2

P31TXD3

P32INT06

P33INT17

P34T08

P35T19

P3711

U4

C1+1

C1-3

C2+4

C2-5

VCC16

GND15

V+2

V-6

R1OUT12

R2OUT9

T1IN11

T2IN10

R1IN13

R2IN8

T1OUT14

T2OUT7

C12 10uF

C16

01uF

C15 10uF

C11

01uF

-5V

+5V

+5V

+5V

+5V

+5V

+5V

+5V

RST

OSC

OSC

RST

DCLKCSDINBUSYDOUT

U1

IN2

GND

4

OUT6

TEMP3

TRIM5

-5V

+5V

Electronic circuit diagram of the magnetic sensor

Photograph of the completed measuring system data acquisition

software in PC and probe scanning system

Experimental Setup for Magnetic Sensor

Reference material Scanning System Software LabVIEW

Reference Material (1) Normal defects and PVCs

Longitudinal and transverse defects

Def W L D Remarks

1 02 500 0213 (20 ) Inner defects

2 02 500 0427 (40 )

3 02 500 0213 (20 )Outer defectsPVC(1018)4 02 500 0427 (40 )

5 02 500 0639 (60 )

6 02 500 0852 (80 )

7 02 500 0639 (60 ) Inner defects

8 02 500 0852 (80 )

- 1 and 2 are inner defects

- 345 and 6 are outer defects with PVC

- 7 and 8 are inner defects

PVC

PVC

Defect Defect

For longitudinal defects and PVC For circumferential defects and PVC

ECT is very difficult to detect circumferential defects

We can distinguish PVCs and defects and longitudinal and circumferential defects

Flux-gate Magnetometer

One core sensor Two core sensor

3-축 flux-gate Magnetometer의 계략도

Sensorpia Co

pro

cess

or(

AV

R)

Sensor 1

RS422

Interface

Mic

ro-p

roce

ssor(

AV

R)

Sensor 2

Sensor 3

Interface

조립된 마그네토미터의 사진

Sensorpia Co

Analog PCB

Digital PCB

Sensorpia Co선형도(linearity)

10

20

30

40

50

60

y-axis

Magnetometer Output (microT)

-60 -50 -40 -30 -20 -10 0 10 20 30 40 50 60

-60

-50

-40

-30

-20

-10

0

10

Y-axis y=099946 x+0015STD 106E-4

Magnetometer Output (

Applied Magnetic Field (microT)

마그네토미터의 noise 특성 Sensorpia Co

1

10

100

y-axis

Magnetometer noise (nT)

0 1 2 3 4 5 6

1E-4

1E-3

001

01

Magnetometer noise (nT)

Frequency (Hz)

Magnetometer for KoDSAT

-150 -100 -50 0 50 100 150

-15

-10

-5

0

5

10

15

Magnetic Moment (Am

2)

Current (mA)

After Thermal Cycle Test

Measured

Resistance 193 ohm

Photograph of Magnetic torquer

Photograph of KoDSAT

Photograph of

3-axis Fluxgate

Magnetometer

Photograph of Magnetic torquer

Application of magnetometer

Moon magnetic fieldmeasurement

Telescope with direction indication

Joule Effect (Magnetostriction)

ϕ2cosel

l=

∆

0=∆

+∆

+∆

b

b

a

a

l

l

Actuator using Terfenol-D

00

05

10

B (T)

800

1000

1200

1400

1600

Magnetostriction (ppm)

-100 -50 0 50 100

-10

-05

00

B (T)

H (kAm)

2 MPa

4 MPa

6 MPa

8 MPa

10 MPa

12 MPa

-100 -50 0 50 100

-200

0

200

400

600

Magnetostriction (ppm)

H (kAm)

2 MPa

4 MPa

6 MPa

8 MPa

10 MPa

12 MPa

600

700

800

900

1000

-4 -3 -2 -1 0 1 2 3 4

0

10

20

30

40

50

60

Displacement (m

icro meter)

I (A)

FIELD

9 kAm

12 kAm

16 kAm

20 kAm

24 kAm

38 kAm

-50 -40 -30 -20 -10 0 10 20 30 40 50

-100

0

100

200

300

400

500

L (PPM)

H (kAm)

9 kAm

12 kAm

16 kAm

20 kAm

24 kAm

38 kAm

Magnetostrictive displacement sensor

Hysteresis loops under

tensile stress σ

(a) Crystalline 68 NiFe

λs = +25 10-6

(b) crystalline pure Ni λs

= -35 10-6

Villari Effect ( Inverse of Joule Effect)

= -35 10-6

(c) amorphous Co-based

alloy

λs = -35 10-6

ϕσλ 2sin2

3sdotsdot= smeE

γ

Permeability depending on the stress

σλmicromicro

1

3

2

Y

J

so

s

r =

γ

Calculated magnetization curves under stress

Variation of magnetization curve by an applied

tensile force (Co-based amorphous alloy)

Alloy Requirement

Materials for magnetoelastic sensors

Why amorphous magnetic materials are important

Stress-strain curves of several materials

Coercivity and hardness of several materials

Principles of magnetoelastic sensors

Non-contact torque sensor

Principle of cross torductor torque

sensor and flux pattern of sensor

poles on the surface of a shaft

a) without and b)with torsional load

Equivalent magnetic circuit of

cross type torque sensor

Helices of principal tensile and compressive stress on the surface of

a shaft subjected to torsion [32] Correlated changes of permeability

are detected by four-branch yoke system with sensing coils 123

and 4 and a common excitation pole

Examples of torque sensors

Four-branch type torque sensor

heads Pole structures realized

by commercial multi-pole

ferrites 14 and 18 min in

diameter (diameter of sensor

h e a d 1 7 a n d 2 4 m m

respectively) respectively)

Principle of Ring Torductor torque transducer

(a b) Physical structure (c) evolution of the

shaft surface under the transducer poles A and BRing torductor for measuring

torque on ship propeller shafts

(shaft diameter ca 500 mm)

(Courtesy ASEA Brown

Boveri AG)

Principal designs of coaxial torque sensors

Schematic diagram of data processing

electronics of a torque sensor

Extensometer (a) Construction of strain sensing element using

amorphous ribbon wound core (b) configuration of lumped

windings

∆E effect of an amorphous FeNi-based

alloy (Fe40 Ni38 Mo4 B18) Hs saturation

field

Magnetically tunable delay line

Torque Sensors using Amorphous wire

Sixtus tonk효과(large Barkhausen효과)

Hysteresis loops of a Wiegand wire for different reset fields

Curie 온도 및Hopkinson효과

Relation between normalised

saturation polarisation and

normalised Curie temperature

Permeability of a Mn-Zn ferrite as

a function of temperature and field

strength

Conclusions

1) Magnetic sensor 는 자동차 공장자동화 항공우주 및 군사용으로많이 사용되고 있다

2) 새로운 소재개발은 자기센서의 성능개발에 직접적인 영향을 준다2) 새로운 소재개발은 자기센서의 성능개발에 직접적인 영향을 준다

3) 센서의 개발을 위해서는 다양한 전공지식이 요구된다

(물리학 재료공학 기계공학 전자공학)

4) 센서분야가 고부가가치를 창출하는 부품사업이다

5) 핵심부품을 생산하는 중소기업의 item으로도 적절하다

Current Sensor Based on Hall Sensor

and Magnetic Core for Hybrid Vehicle

KH Yeon1 SD Kim1 and D Son2 1Auto industry co14F Hanshin IT tower Guro Gu Seoul Korea2Hannam UniversityOjung dong 133 Daejeon Rep of Korea

i

Hall sensor

B

I

SB

ring core

B

I10

g

N

Bl S

micro

)( gtgtrmicro

gab core

Current Sensor Based on Hall

Sensor and Magnetic Core

Hall

Effect

Device

CurrentVoltage

applying for

Hall effect device

operation

Output

signals

Magnetic field

Occurred by

current measurement

Signal

process

circuits

Developed Current Sensor

Magnetic core

Hall sensor

PCB

25

30

35

40

45

50

Output voltage V

Current sensor(Open loop type)

Temp 25C

400A model

+400 ~ -400A

SD 000128

Linearity 003

Linearity of the sensor

Characteristics of the Current Sensors

1000A 10 V power supply

-500 -400 -300 -200 -100 0 100 200 300 400 500

00

05

10

15

20

Output voltage V

current A

Temperature 25Linearity 003

Measuring range -400A ~ +400A

1000A Electronic Load

-3

0

3

6

9

12

15

18

dB

Current sensor

DV2 PCB 24pF

40Aturns

Frequency bandwidth

Gain bandwidth 3 MHz

Current 10 A

Temperature 25

Frequency bandwidth 100 kHz

Sensor output voltage vs frequency

at applied current of 40 Aturns

1 10 100

-18

-15

-12

-9

-6

Frequency kHz 측정온도 25

주파수특성 30kHz 이상(3dB 기준)

측정전류 40Aturns(4A 10턴)

측정주파수 100Hz ~ 100kHz

Temperature 25Current 40Aturns

Frequency range 100 Hz ~ 100 kHz

What is Magnetoresistance

Magnetoresistance effect(AMR)

θθθ 2cos2

12sin12cos(

22 minusminus+∆asymp∆ xxxmx hhhRR

32 minusasymp∆ ρρ New effect GMR CMR and GMI

10 ge∆ ρρ

Two bridge configuration for

rotational angle measurement

measurement angle more than 180o

자동차 Engine Management System

Inductive and Eddy Current

Sensors Excited by Permanent Magnets

tNtU dd)( φsdotminus=

construction of an inductive

sensor (courtesy VDO Adolf sensor (courtesy VDO Adolf

Schindling AG)

1) constant socket

2) terminal package

3) permanent magnet

4) cap

5) soft magnetic core

6) coil

7) plate

8) blade connector

γγ

Sensor with yoke Change in the magnetic flux with

varying air gap Continuous lines

minimum air gap dashed lines

maximum air gap

C-shaped sensor

Sensor with radially

magnetized

permanent magnet

Signal Conditioning

Output voltage U of a DC-excited sensor with permanent

magnets when a single iron object passes by

Schematic electrical diagram of an inductive sensor

Linear Variable Differential Transformer

AC-Excited Sensors for Linear Movement

Principle of construction of an LVDT

Electrical circuit of an LVDT

tIMtNU dd dd sdotminus=sdotminus= φ

tIMtIMUUU dd dd 1212 sdotminussdot=minus=

tIMMU dd)( 12 sdotminus=

)(12 xMMMM =minus=

tIxMU dd)( sdot= tI

UxM

dd)( =

Signal Conditioning

power supply

carrier gen

autoampcontrol

LVDTcarrieramp

demod-ulator

phase

shifter

power supply

carrier gen

passivedemod-ulator

LVDTDCamp

Block diagram of a carrier amplifier system

Block diagram of a DC amplifier system

Variable Inductive Sensors

Principle of construction

of the VLP sensor

Principle of a bridge

circuit

lANL r 20 sdotsdotsdot= micromicro

21 BA UUU minus=

21)i(ii( 211 minus+sdot= LLLUU BA ωωω

)21))()((( minus∆minus+∆+∆+sdot= LLLLLLUU BA

)212)(( minus∆+sdot= LLLUU )212)(( minus∆+sdot= LLLUU BA

LLUU BA 21 ∆sdotsdot=

llLL ∆sdot=∆ d d

llLLUU BA ∆sdotsdot= d d)2(1

Applications and Properties

Principle of a construction of a force transducer

(courtesy Hottinger Baldwin Messtechnik)

Vibrationacceleration sensor

Signal Conditioning

Schematic electrical diagram of a force transducer connected with an

amplifier (courtesy Hottinger Baldwin Messtechnik GmbH)

Variable Gap Sensors

)( FeFe2

0 LLllANL micromicromicro +sdotsdot=

FeFe2

0max lANL sdotsdotsdot= micromicro

Construction of a variable gap sensor

Characteristic of a variable gap sensor

Construction of a differential

cross-anchor sensor

Output voltage U versus core

position x plusmn a limits of the

linear rage

Applications of differential cross-anchor sensors

AC-excited Sensors for Rotary Movements

Principle of construction of a synchro

α cos10 sdotsdot= UKU y

)120-( cos10 degsdotsdot= αUKU z

)240-( cos10 degsdotsdot= αUKU x

)120-( sin3100 degsdotsdotsdot=minus= αKUUUU yxyx

)240-( sin3100 degsdotsdotsdot=minus= αKUUUU zyzy

α sin3100 sdotsdotsdot=minus= KUUUU xzxz

Application to the Torque Sensor

Principle of construction of a torque-type synchro

Torque versus angular

difference

)( sin~ rt αα minussdotKM

)( cos~ rt1r αα minussdotUU

Principle of construction of a control-type sensor

Output voltage versus

angular difference

Principle of construction of a differential sychro

Eddy Current Sensors

tBE dd curl minus=JH = curl

0 div =BH(H)B sdot= micro

E(E)J sdot= σ

A B curl= A B curl=

tdd- A E =

)dd( tAJ minus= σ

tdd curl curl AA σmicro minus=

AA) σωmicro iminus= curl )(curl(1

AA) σωmicro i=∆)((1

Eddy Current Tachometer

Construction of a speedometer (courtesy VDO Adolf Schinding AG) 1) spindle 2) bearing

3) holding spring 4) iron yoke 5) eddy current cup 6) shaft of the magnet 7) support of

the magnet 8) temperature compensation 9) permanent magnet 10) torsion spring

Proximity Sensors

Schematic diagram of a proximity sensor

Output current of a proximity switch versus distance

Inductive Flowmeters

)( Btimessdot= υqF

EqF sdot=BE times=υ

)(ds Btimes== υEU )(ds Btimes== υEU

)( Bd timessdot= υU

Bsdotsdotsdot= υdKU

Development of magnetic phase detection

sensor for steam generator tube

Dirac Son1 Kwan-Sang Ryu2 Duck-Gun Park3

1Hannam University Daejeon Rep of Korea2Korea Research Institute of Standards and Science Daejeon Rep of Korea3KoreaAtomic Energy Research Institute Daejeon Rep of Korea

Introduction

The layout of pressurized water reactor (PWR) components

Primary side Secondary side (non-radioactive side)(radioactive side)

The Structure of SG(Steam Generator)(degradation mechanism)

Secondary SidePrimary Side

SCC

A B

A-B

Steam outlet

Anti-vibration

SCC

Fretting

Wall thinning

IGA

U-bend

In commercial power plants SG- height up to 21 m - weight up to 800 tons - 2~4 sets of SG were installed - SG can contain from 3000 to

16000 tubes each about 20 mmin diameter

Primary coolant outlet Primary coolant inlet

Anti-vibrationbars

Tubesupportplate

Tubesheet

IGA

SCC

Pitting

SCC

Inside Tubesheet

Top of Tubesheet

by SSHwang of KAERI

Denting

Sludge pile

in diameter

The SGT is made of nickel basedInconel alloy which is composed of 75 Ni 165Cr and 815Fe

-Degradation mechanism corrosion pitting denting inter granular attack

-Inspection Eddy current Testing(ECT)

Permeability Variation Clusters (PVC)

(Ferro-magnetic phase)

-005

000

005

010

015

m (emug)

1-1

-002

000

002

004

006

008

m (emug)

1-2

-1000 -500 0 500 1000

-015

-010

-005

H ( Am )

-1000 -500 0 500 1000

-006

-004

-002

H ( Am )

The hystresis loop in the fragment of PVC parts of Kori-1 retired SG tube

-004

-002

000

002

004

006

M (emug)

Inconel 600 tested at RT

under tensile stress

1 2 3

4 5 6

7 8 9-004

-002

000

002

004

006

M(emug)

Inconel 600 Heat treated at

602 oC under tensile stress

1 2 3

How can we detect magnetic phase

(PVC)selectively from the flaws in SGT

-3000 -2000 -1000 0 1000 2000 3000

-006

H (Oe)

7 8 9

10 11 12

-3000 -2000 -1000 0 1000 2000 3000

-006

-004

H(Oe)

4 5 6

7 8 9

The hysteresis loop of the tensile tested specimen at room temperature (a) and tensile tested at high temperature (b)

The magnetic phase can be created under the high temperature andpressure conditions which is correspond to the stress corrosion crackingin the SG tube in the NPP(Bruemmer SM Charlot LA amp Henager CH (1988) Corrosion 782)

Principle of ECT

If we can separate magnetic phase selectively from the

flaws using magnetic sensor the reliability of EC in SGT

inspection will be greatly enhanced

Structure of the permeability

sensor

Dimension and photograph of U-shape

sensing yoke

Design of Magnetic Sensor for PVC

sensor sensing yoke

Photograph of the completed sensor front side (above) and rear side (bottom)

R11R12

R10

R8

R6

R9

R13

R7

R14

C18

1 n

C17

C20

C21

D2

DIODE

SIN COS

-

+

U-2A

4

13

2

-

+

U-2B

75

6

8

-

+

U-3A

13

2

8

+5VC19

104

+5V

Schematic diagram of the sensor system

Electronic Circuit of Magnetic Sensor

R20

R

R21

R

-

+

U5AD797

3

26

74

U6

D1

S12

GND3

+VCC4VCC5

IN6

-VCC7

S28

C41

R13

R26

R18

R25

R2210 Ω

R16

R14

R17

10 k

R15

R27

R32

R28

R33

R29

R34

5 k

R30

C29

C37

104

C32473

C39473C40

104

C33

104

C21

104C23

104

C25

104

C26

104

C30

104

C31

104

C35

104

C36

104

C27

104

C28

104

C34

104

C38

104

D3

DIODE

L1

1

2

L2

1

2

L3

1

2

4

-

+

U-4A

4

13

2

-

+

U-4B

75

6

8

-

+

U-5A

4

13

2

-

+

U-5B

75

6

8

-

+

U-6A

4

13

2

-

+

U-6B

75

6

8

C22

104

-5V

+5V

+5V

+5V

+5V

+5V

+5V

U7

D1

S12

GND3

+VCC4

VCC5

IN6

-VCC7

S28

+5V

-5V

-5V

-5V

-5V

-5V

-5V

-5V

-5V

R19

R24

R

R23

R

C24

OUT(X)

OUT(Y)

R1

20 kR210 k

R3

20 kR410 k

C1

104

C8

104

REF43

OUT(X)

OUT(Y)

REF43

U2

+Vcc1

CH02

CH13

CH24

CH35

COMM6

SHDN7

Vref8

+Vcc9

GND10

GND11

DOUT12BUSY13DIN14CS15

DIN16

-

+

U-1A

13

2

8

-

+

U-1B

4

75

6

C410 uF

C5104

DOUT

C210uF

C6104

C3104

DCLK

C7104

DIN

C10

01uF

CS

BUSY

C14 10uF

J1

CON6

123456

D1

DIODE

R5

47K

C9

10uF

C1310uF

Y1

OSC

OUT3

GND2

VCC4

U3

RSTVPP1

GND10

VCC20

XTAL15

XTAL24

P10AIN012P11AIN113P1214P1315P1416P1517P1618P1719

P30RXD2

P31TXD3

P32INT06

P33INT17

P34T08

P35T19

P3711

U4

C1+1

C1-3

C2+4

C2-5

VCC16

GND15

V+2

V-6

R1OUT12

R2OUT9

T1IN11

T2IN10

R1IN13

R2IN8

T1OUT14

T2OUT7

C12 10uF

C16

01uF

C15 10uF

C11

01uF

-5V

+5V

+5V

+5V

+5V

+5V

+5V

+5V

RST

OSC

OSC

RST

DCLKCSDINBUSYDOUT

U1

IN2

GND

4

OUT6

TEMP3

TRIM5

-5V

+5V

Electronic circuit diagram of the magnetic sensor

Photograph of the completed measuring system data acquisition

software in PC and probe scanning system

Experimental Setup for Magnetic Sensor

Reference material Scanning System Software LabVIEW

Reference Material (1) Normal defects and PVCs

Longitudinal and transverse defects

Def W L D Remarks

1 02 500 0213 (20 ) Inner defects

2 02 500 0427 (40 )

3 02 500 0213 (20 )Outer defectsPVC(1018)4 02 500 0427 (40 )

5 02 500 0639 (60 )

6 02 500 0852 (80 )

7 02 500 0639 (60 ) Inner defects

8 02 500 0852 (80 )

- 1 and 2 are inner defects

- 345 and 6 are outer defects with PVC

- 7 and 8 are inner defects

PVC

PVC

Defect Defect

For longitudinal defects and PVC For circumferential defects and PVC

ECT is very difficult to detect circumferential defects

We can distinguish PVCs and defects and longitudinal and circumferential defects

Flux-gate Magnetometer

One core sensor Two core sensor

3-축 flux-gate Magnetometer의 계략도

Sensorpia Co

pro

cess

or(

AV

R)

Sensor 1

RS422

Interface

Mic

ro-p

roce

ssor(

AV

R)

Sensor 2

Sensor 3

Interface

조립된 마그네토미터의 사진

Sensorpia Co

Analog PCB

Digital PCB

Sensorpia Co선형도(linearity)

10

20

30

40

50

60

y-axis

Magnetometer Output (microT)

-60 -50 -40 -30 -20 -10 0 10 20 30 40 50 60

-60

-50

-40

-30

-20

-10

0

10

Y-axis y=099946 x+0015STD 106E-4

Magnetometer Output (

Applied Magnetic Field (microT)

마그네토미터의 noise 특성 Sensorpia Co

1

10

100

y-axis

Magnetometer noise (nT)

0 1 2 3 4 5 6

1E-4

1E-3

001

01

Magnetometer noise (nT)

Frequency (Hz)

Magnetometer for KoDSAT

-150 -100 -50 0 50 100 150

-15

-10

-5

0

5

10

15

Magnetic Moment (Am

2)

Current (mA)

After Thermal Cycle Test

Measured

Resistance 193 ohm

Photograph of Magnetic torquer

Photograph of KoDSAT

Photograph of

3-axis Fluxgate

Magnetometer

Photograph of Magnetic torquer

Application of magnetometer

Moon magnetic fieldmeasurement

Telescope with direction indication

Joule Effect (Magnetostriction)

ϕ2cosel

l=

∆

0=∆

+∆

+∆

b

b

a

a

l

l

Actuator using Terfenol-D

00

05

10

B (T)

800

1000

1200

1400

1600

Magnetostriction (ppm)

-100 -50 0 50 100

-10

-05

00

B (T)

H (kAm)

2 MPa

4 MPa

6 MPa

8 MPa

10 MPa

12 MPa

-100 -50 0 50 100

-200

0

200

400

600

Magnetostriction (ppm)

H (kAm)

2 MPa

4 MPa

6 MPa

8 MPa

10 MPa

12 MPa

600

700

800

900

1000

-4 -3 -2 -1 0 1 2 3 4

0

10

20

30

40

50

60

Displacement (m

icro meter)

I (A)

FIELD

9 kAm

12 kAm

16 kAm

20 kAm

24 kAm

38 kAm

-50 -40 -30 -20 -10 0 10 20 30 40 50

-100

0

100

200

300

400

500

L (PPM)

H (kAm)

9 kAm

12 kAm

16 kAm

20 kAm

24 kAm

38 kAm

Magnetostrictive displacement sensor

Hysteresis loops under

tensile stress σ

(a) Crystalline 68 NiFe

λs = +25 10-6

(b) crystalline pure Ni λs

= -35 10-6

Villari Effect ( Inverse of Joule Effect)

= -35 10-6

(c) amorphous Co-based

alloy

λs = -35 10-6

ϕσλ 2sin2

3sdotsdot= smeE

γ

Permeability depending on the stress

σλmicromicro

1

3

2

Y

J

so

s

r =

γ

Calculated magnetization curves under stress

Variation of magnetization curve by an applied

tensile force (Co-based amorphous alloy)

Alloy Requirement

Materials for magnetoelastic sensors

Why amorphous magnetic materials are important

Stress-strain curves of several materials

Coercivity and hardness of several materials

Principles of magnetoelastic sensors

Non-contact torque sensor

Principle of cross torductor torque

sensor and flux pattern of sensor

poles on the surface of a shaft

a) without and b)with torsional load

Equivalent magnetic circuit of

cross type torque sensor

Helices of principal tensile and compressive stress on the surface of

a shaft subjected to torsion [32] Correlated changes of permeability

are detected by four-branch yoke system with sensing coils 123

and 4 and a common excitation pole

Examples of torque sensors

Four-branch type torque sensor

heads Pole structures realized

by commercial multi-pole

ferrites 14 and 18 min in

diameter (diameter of sensor

h e a d 1 7 a n d 2 4 m m

respectively) respectively)

Principle of Ring Torductor torque transducer

(a b) Physical structure (c) evolution of the

shaft surface under the transducer poles A and BRing torductor for measuring

torque on ship propeller shafts

(shaft diameter ca 500 mm)

(Courtesy ASEA Brown

Boveri AG)

Principal designs of coaxial torque sensors

Schematic diagram of data processing

electronics of a torque sensor

Extensometer (a) Construction of strain sensing element using

amorphous ribbon wound core (b) configuration of lumped

windings

∆E effect of an amorphous FeNi-based

alloy (Fe40 Ni38 Mo4 B18) Hs saturation

field

Magnetically tunable delay line

Torque Sensors using Amorphous wire

Sixtus tonk효과(large Barkhausen효과)

Hysteresis loops of a Wiegand wire for different reset fields

Curie 온도 및Hopkinson효과

Relation between normalised

saturation polarisation and

normalised Curie temperature

Permeability of a Mn-Zn ferrite as

a function of temperature and field

strength

Conclusions

1) Magnetic sensor 는 자동차 공장자동화 항공우주 및 군사용으로많이 사용되고 있다

2) 새로운 소재개발은 자기센서의 성능개발에 직접적인 영향을 준다2) 새로운 소재개발은 자기센서의 성능개발에 직접적인 영향을 준다

3) 센서의 개발을 위해서는 다양한 전공지식이 요구된다

(물리학 재료공학 기계공학 전자공학)

4) 센서분야가 고부가가치를 창출하는 부품사업이다

5) 핵심부품을 생산하는 중소기업의 item으로도 적절하다

i

Hall sensor

B

I

SB

ring core

B

I10

g

N

Bl S

micro

)( gtgtrmicro

gab core

Current Sensor Based on Hall

Sensor and Magnetic Core

Hall

Effect

Device

CurrentVoltage

applying for

Hall effect device

operation

Output

signals

Magnetic field

Occurred by

current measurement

Signal

process

circuits

Developed Current Sensor

Magnetic core

Hall sensor

PCB

25

30

35

40

45

50

Output voltage V

Current sensor(Open loop type)

Temp 25C

400A model

+400 ~ -400A

SD 000128

Linearity 003

Linearity of the sensor

Characteristics of the Current Sensors

1000A 10 V power supply

-500 -400 -300 -200 -100 0 100 200 300 400 500

00

05

10

15

20

Output voltage V

current A

Temperature 25Linearity 003

Measuring range -400A ~ +400A

1000A Electronic Load

-3

0

3

6

9

12

15

18

dB

Current sensor

DV2 PCB 24pF

40Aturns

Frequency bandwidth

Gain bandwidth 3 MHz

Current 10 A

Temperature 25

Frequency bandwidth 100 kHz

Sensor output voltage vs frequency

at applied current of 40 Aturns

1 10 100

-18

-15

-12

-9

-6

Frequency kHz 측정온도 25

주파수특성 30kHz 이상(3dB 기준)

측정전류 40Aturns(4A 10턴)

측정주파수 100Hz ~ 100kHz

Temperature 25Current 40Aturns

Frequency range 100 Hz ~ 100 kHz

What is Magnetoresistance

Magnetoresistance effect(AMR)

θθθ 2cos2

12sin12cos(

22 minusminus+∆asymp∆ xxxmx hhhRR

32 minusasymp∆ ρρ New effect GMR CMR and GMI

10 ge∆ ρρ

Two bridge configuration for

rotational angle measurement

measurement angle more than 180o

자동차 Engine Management System

Inductive and Eddy Current

Sensors Excited by Permanent Magnets

tNtU dd)( φsdotminus=

construction of an inductive

sensor (courtesy VDO Adolf sensor (courtesy VDO Adolf

Schindling AG)

1) constant socket

2) terminal package

3) permanent magnet

4) cap

5) soft magnetic core

6) coil

7) plate

8) blade connector

γγ

Sensor with yoke Change in the magnetic flux with

varying air gap Continuous lines

minimum air gap dashed lines

maximum air gap

C-shaped sensor

Sensor with radially

magnetized

permanent magnet

Signal Conditioning

Output voltage U of a DC-excited sensor with permanent

magnets when a single iron object passes by

Schematic electrical diagram of an inductive sensor

Linear Variable Differential Transformer

AC-Excited Sensors for Linear Movement

Principle of construction of an LVDT

Electrical circuit of an LVDT

tIMtNU dd dd sdotminus=sdotminus= φ

tIMtIMUUU dd dd 1212 sdotminussdot=minus=

tIMMU dd)( 12 sdotminus=

)(12 xMMMM =minus=

tIxMU dd)( sdot= tI

UxM

dd)( =

Signal Conditioning

power supply

carrier gen

autoampcontrol

LVDTcarrieramp

demod-ulator

phase

shifter

power supply

carrier gen

passivedemod-ulator

LVDTDCamp

Block diagram of a carrier amplifier system

Block diagram of a DC amplifier system

Variable Inductive Sensors

Principle of construction

of the VLP sensor

Principle of a bridge

circuit

lANL r 20 sdotsdotsdot= micromicro

21 BA UUU minus=

21)i(ii( 211 minus+sdot= LLLUU BA ωωω

)21))()((( minus∆minus+∆+∆+sdot= LLLLLLUU BA

)212)(( minus∆+sdot= LLLUU )212)(( minus∆+sdot= LLLUU BA

LLUU BA 21 ∆sdotsdot=

llLL ∆sdot=∆ d d

llLLUU BA ∆sdotsdot= d d)2(1

Applications and Properties

Principle of a construction of a force transducer

(courtesy Hottinger Baldwin Messtechnik)

Vibrationacceleration sensor

Signal Conditioning

Schematic electrical diagram of a force transducer connected with an

amplifier (courtesy Hottinger Baldwin Messtechnik GmbH)

Variable Gap Sensors

)( FeFe2

0 LLllANL micromicromicro +sdotsdot=

FeFe2

0max lANL sdotsdotsdot= micromicro

Construction of a variable gap sensor

Characteristic of a variable gap sensor

Construction of a differential

cross-anchor sensor

Output voltage U versus core

position x plusmn a limits of the

linear rage

Applications of differential cross-anchor sensors

AC-excited Sensors for Rotary Movements

Principle of construction of a synchro

α cos10 sdotsdot= UKU y

)120-( cos10 degsdotsdot= αUKU z

)240-( cos10 degsdotsdot= αUKU x

)120-( sin3100 degsdotsdotsdot=minus= αKUUUU yxyx

)240-( sin3100 degsdotsdotsdot=minus= αKUUUU zyzy

α sin3100 sdotsdotsdot=minus= KUUUU xzxz

Application to the Torque Sensor

Principle of construction of a torque-type synchro

Torque versus angular

difference

)( sin~ rt αα minussdotKM

)( cos~ rt1r αα minussdotUU

Principle of construction of a control-type sensor

Output voltage versus

angular difference

Principle of construction of a differential sychro

Eddy Current Sensors

tBE dd curl minus=JH = curl

0 div =BH(H)B sdot= micro

E(E)J sdot= σ

A B curl= A B curl=

tdd- A E =

)dd( tAJ minus= σ

tdd curl curl AA σmicro minus=

AA) σωmicro iminus= curl )(curl(1

AA) σωmicro i=∆)((1

Eddy Current Tachometer

Construction of a speedometer (courtesy VDO Adolf Schinding AG) 1) spindle 2) bearing

3) holding spring 4) iron yoke 5) eddy current cup 6) shaft of the magnet 7) support of

the magnet 8) temperature compensation 9) permanent magnet 10) torsion spring

Proximity Sensors

Schematic diagram of a proximity sensor

Output current of a proximity switch versus distance

Inductive Flowmeters

)( Btimessdot= υqF

EqF sdot=BE times=υ

)(ds Btimes== υEU )(ds Btimes== υEU

)( Bd timessdot= υU

Bsdotsdotsdot= υdKU

Development of magnetic phase detection

sensor for steam generator tube

Dirac Son1 Kwan-Sang Ryu2 Duck-Gun Park3

1Hannam University Daejeon Rep of Korea2Korea Research Institute of Standards and Science Daejeon Rep of Korea3KoreaAtomic Energy Research Institute Daejeon Rep of Korea

Introduction

The layout of pressurized water reactor (PWR) components

Primary side Secondary side (non-radioactive side)(radioactive side)

The Structure of SG(Steam Generator)(degradation mechanism)

Secondary SidePrimary Side

SCC

A B

A-B

Steam outlet

Anti-vibration

SCC

Fretting

Wall thinning

IGA

U-bend

In commercial power plants SG- height up to 21 m - weight up to 800 tons - 2~4 sets of SG were installed - SG can contain from 3000 to

16000 tubes each about 20 mmin diameter

Primary coolant outlet Primary coolant inlet

Anti-vibrationbars

Tubesupportplate

Tubesheet

IGA

SCC

Pitting

SCC

Inside Tubesheet

Top of Tubesheet

by SSHwang of KAERI

Denting

Sludge pile

in diameter

The SGT is made of nickel basedInconel alloy which is composed of 75 Ni 165Cr and 815Fe

-Degradation mechanism corrosion pitting denting inter granular attack

-Inspection Eddy current Testing(ECT)

Permeability Variation Clusters (PVC)

(Ferro-magnetic phase)

-005

000

005

010

015

m (emug)

1-1

-002

000

002

004

006

008

m (emug)

1-2

-1000 -500 0 500 1000

-015

-010

-005

H ( Am )

-1000 -500 0 500 1000

-006

-004

-002

H ( Am )

The hystresis loop in the fragment of PVC parts of Kori-1 retired SG tube

-004

-002

000

002

004

006

M (emug)

Inconel 600 tested at RT

under tensile stress

1 2 3

4 5 6

7 8 9-004

-002

000

002

004

006

M(emug)

Inconel 600 Heat treated at

602 oC under tensile stress

1 2 3

How can we detect magnetic phase

(PVC)selectively from the flaws in SGT

-3000 -2000 -1000 0 1000 2000 3000

-006

H (Oe)

7 8 9

10 11 12

-3000 -2000 -1000 0 1000 2000 3000

-006

-004

H(Oe)

4 5 6

7 8 9

The hysteresis loop of the tensile tested specimen at room temperature (a) and tensile tested at high temperature (b)

The magnetic phase can be created under the high temperature andpressure conditions which is correspond to the stress corrosion crackingin the SG tube in the NPP(Bruemmer SM Charlot LA amp Henager CH (1988) Corrosion 782)

Principle of ECT

If we can separate magnetic phase selectively from the

flaws using magnetic sensor the reliability of EC in SGT

inspection will be greatly enhanced

Structure of the permeability

sensor

Dimension and photograph of U-shape

sensing yoke

Design of Magnetic Sensor for PVC

sensor sensing yoke

Photograph of the completed sensor front side (above) and rear side (bottom)

R11R12

R10

R8

R6

R9

R13

R7

R14

C18

1 n

C17

C20

C21

D2

DIODE

SIN COS

-

+

U-2A

4

13

2

-

+

U-2B

75

6

8

-

+

U-3A

13

2

8

+5VC19

104

+5V

Schematic diagram of the sensor system

Electronic Circuit of Magnetic Sensor

R20

R

R21

R

-

+

U5AD797

3

26

74

U6

D1

S12

GND3

+VCC4VCC5

IN6

-VCC7

S28

C41

R13

R26

R18

R25

R2210 Ω

R16

R14

R17

10 k

R15

R27

R32

R28

R33

R29

R34

5 k

R30

C29

C37

104

C32473

C39473C40

104

C33

104

C21

104C23

104

C25

104

C26

104

C30

104

C31

104

C35

104

C36

104

C27

104

C28

104

C34

104

C38

104

D3

DIODE

L1

1

2

L2

1

2

L3

1

2

4

-

+

U-4A

4

13

2

-

+

U-4B

75

6

8

-

+

U-5A

4

13

2

-

+

U-5B

75

6

8

-

+

U-6A

4

13

2

-

+

U-6B

75

6

8

C22

104

-5V

+5V

+5V

+5V

+5V

+5V

+5V

U7

D1

S12

GND3

+VCC4

VCC5

IN6

-VCC7

S28

+5V

-5V

-5V

-5V

-5V

-5V

-5V

-5V

-5V

R19

R24

R

R23

R

C24

OUT(X)

OUT(Y)

R1

20 kR210 k

R3

20 kR410 k

C1

104

C8

104

REF43

OUT(X)

OUT(Y)

REF43

U2

+Vcc1

CH02

CH13

CH24

CH35

COMM6

SHDN7

Vref8

+Vcc9

GND10

GND11

DOUT12BUSY13DIN14CS15

DIN16

-

+

U-1A

13

2

8

-

+

U-1B

4

75

6

C410 uF

C5104

DOUT

C210uF

C6104

C3104

DCLK

C7104

DIN

C10

01uF

CS

BUSY

C14 10uF

J1

CON6

123456

D1

DIODE

R5

47K

C9

10uF

C1310uF

Y1

OSC

OUT3

GND2

VCC4

U3

RSTVPP1

GND10

VCC20

XTAL15

XTAL24

P10AIN012P11AIN113P1214P1315P1416P1517P1618P1719

P30RXD2

P31TXD3

P32INT06

P33INT17

P34T08

P35T19

P3711

U4

C1+1

C1-3

C2+4

C2-5

VCC16

GND15

V+2

V-6

R1OUT12

R2OUT9

T1IN11

T2IN10

R1IN13

R2IN8

T1OUT14

T2OUT7

C12 10uF

C16

01uF

C15 10uF

C11

01uF

-5V

+5V

+5V

+5V

+5V

+5V

+5V

+5V

RST

OSC

OSC

RST

DCLKCSDINBUSYDOUT

U1

IN2

GND

4

OUT6

TEMP3

TRIM5

-5V

+5V

Electronic circuit diagram of the magnetic sensor

Photograph of the completed measuring system data acquisition

software in PC and probe scanning system

Experimental Setup for Magnetic Sensor

Reference material Scanning System Software LabVIEW

Reference Material (1) Normal defects and PVCs

Longitudinal and transverse defects

Def W L D Remarks

1 02 500 0213 (20 ) Inner defects

2 02 500 0427 (40 )

3 02 500 0213 (20 )Outer defectsPVC(1018)4 02 500 0427 (40 )

5 02 500 0639 (60 )

6 02 500 0852 (80 )

7 02 500 0639 (60 ) Inner defects

8 02 500 0852 (80 )

- 1 and 2 are inner defects

- 345 and 6 are outer defects with PVC

- 7 and 8 are inner defects

PVC

PVC

Defect Defect

For longitudinal defects and PVC For circumferential defects and PVC

ECT is very difficult to detect circumferential defects

We can distinguish PVCs and defects and longitudinal and circumferential defects

Flux-gate Magnetometer

One core sensor Two core sensor

3-축 flux-gate Magnetometer의 계략도

Sensorpia Co

pro

cess

or(

AV

R)

Sensor 1

RS422

Interface

Mic

ro-p

roce

ssor(

AV

R)

Sensor 2

Sensor 3

Interface

조립된 마그네토미터의 사진

Sensorpia Co

Analog PCB

Digital PCB

Sensorpia Co선형도(linearity)

10

20

30

40

50

60

y-axis

Magnetometer Output (microT)

-60 -50 -40 -30 -20 -10 0 10 20 30 40 50 60

-60

-50

-40

-30

-20

-10

0

10

Y-axis y=099946 x+0015STD 106E-4

Magnetometer Output (

Applied Magnetic Field (microT)

마그네토미터의 noise 특성 Sensorpia Co

1

10

100

y-axis

Magnetometer noise (nT)

0 1 2 3 4 5 6

1E-4

1E-3

001

01

Magnetometer noise (nT)

Frequency (Hz)

Magnetometer for KoDSAT

-150 -100 -50 0 50 100 150

-15

-10

-5

0

5

10

15

Magnetic Moment (Am

2)

Current (mA)

After Thermal Cycle Test

Measured

Resistance 193 ohm

Photograph of Magnetic torquer

Photograph of KoDSAT

Photograph of

3-axis Fluxgate

Magnetometer

Photograph of Magnetic torquer

Application of magnetometer

Moon magnetic fieldmeasurement

Telescope with direction indication

Joule Effect (Magnetostriction)

ϕ2cosel

l=

∆

0=∆

+∆

+∆

b

b

a

a

l

l

Actuator using Terfenol-D

00

05

10

B (T)

800

1000

1200

1400

1600

Magnetostriction (ppm)

-100 -50 0 50 100

-10

-05

00

B (T)

H (kAm)

2 MPa

4 MPa

6 MPa

8 MPa

10 MPa

12 MPa

-100 -50 0 50 100

-200

0

200

400

600

Magnetostriction (ppm)

H (kAm)

2 MPa

4 MPa

6 MPa

8 MPa

10 MPa

12 MPa

600

700

800

900

1000

-4 -3 -2 -1 0 1 2 3 4

0

10

20

30

40

50

60

Displacement (m

icro meter)

I (A)

FIELD

9 kAm

12 kAm

16 kAm

20 kAm

24 kAm

38 kAm

-50 -40 -30 -20 -10 0 10 20 30 40 50

-100

0

100

200

300

400

500

L (PPM)

H (kAm)

9 kAm

12 kAm

16 kAm

20 kAm

24 kAm

38 kAm

Magnetostrictive displacement sensor

Hysteresis loops under

tensile stress σ

(a) Crystalline 68 NiFe

λs = +25 10-6

(b) crystalline pure Ni λs

= -35 10-6

Villari Effect ( Inverse of Joule Effect)

= -35 10-6

(c) amorphous Co-based

alloy

λs = -35 10-6

ϕσλ 2sin2

3sdotsdot= smeE

γ

Permeability depending on the stress

σλmicromicro

1

3

2

Y

J

so

s

r =

γ

Calculated magnetization curves under stress

Variation of magnetization curve by an applied

tensile force (Co-based amorphous alloy)

Alloy Requirement

Materials for magnetoelastic sensors

Why amorphous magnetic materials are important

Stress-strain curves of several materials

Coercivity and hardness of several materials

Principles of magnetoelastic sensors

Non-contact torque sensor

Principle of cross torductor torque

sensor and flux pattern of sensor

poles on the surface of a shaft

a) without and b)with torsional load

Equivalent magnetic circuit of

cross type torque sensor

Helices of principal tensile and compressive stress on the surface of

a shaft subjected to torsion [32] Correlated changes of permeability

are detected by four-branch yoke system with sensing coils 123

and 4 and a common excitation pole

Examples of torque sensors

Four-branch type torque sensor

heads Pole structures realized

by commercial multi-pole

ferrites 14 and 18 min in

diameter (diameter of sensor

h e a d 1 7 a n d 2 4 m m

respectively) respectively)

Principle of Ring Torductor torque transducer

(a b) Physical structure (c) evolution of the

shaft surface under the transducer poles A and BRing torductor for measuring

torque on ship propeller shafts

(shaft diameter ca 500 mm)

(Courtesy ASEA Brown

Boveri AG)

Principal designs of coaxial torque sensors

Schematic diagram of data processing

electronics of a torque sensor

Extensometer (a) Construction of strain sensing element using

amorphous ribbon wound core (b) configuration of lumped

windings

∆E effect of an amorphous FeNi-based

alloy (Fe40 Ni38 Mo4 B18) Hs saturation

field

Magnetically tunable delay line

Torque Sensors using Amorphous wire

Sixtus tonk효과(large Barkhausen효과)

Hysteresis loops of a Wiegand wire for different reset fields

Curie 온도 및Hopkinson효과

Relation between normalised

saturation polarisation and

normalised Curie temperature

Permeability of a Mn-Zn ferrite as

a function of temperature and field

strength

Conclusions

1) Magnetic sensor 는 자동차 공장자동화 항공우주 및 군사용으로많이 사용되고 있다

2) 새로운 소재개발은 자기센서의 성능개발에 직접적인 영향을 준다2) 새로운 소재개발은 자기센서의 성능개발에 직접적인 영향을 준다

3) 센서의 개발을 위해서는 다양한 전공지식이 요구된다

(물리학 재료공학 기계공학 전자공학)

4) 센서분야가 고부가가치를 창출하는 부품사업이다

5) 핵심부품을 생산하는 중소기업의 item으로도 적절하다

Developed Current Sensor

Magnetic core

Hall sensor

PCB

25

30

35

40

45

50

Output voltage V

Current sensor(Open loop type)

Temp 25C

400A model

+400 ~ -400A

SD 000128

Linearity 003

Linearity of the sensor

Characteristics of the Current Sensors

1000A 10 V power supply

-500 -400 -300 -200 -100 0 100 200 300 400 500

00

05

10

15

20

Output voltage V

current A

Temperature 25Linearity 003

Measuring range -400A ~ +400A

1000A Electronic Load

-3

0

3

6

9

12

15

18

dB

Current sensor

DV2 PCB 24pF

40Aturns

Frequency bandwidth

Gain bandwidth 3 MHz

Current 10 A

Temperature 25

Frequency bandwidth 100 kHz

Sensor output voltage vs frequency

at applied current of 40 Aturns

1 10 100

-18

-15

-12

-9

-6

Frequency kHz 측정온도 25

주파수특성 30kHz 이상(3dB 기준)

측정전류 40Aturns(4A 10턴)

측정주파수 100Hz ~ 100kHz

Temperature 25Current 40Aturns

Frequency range 100 Hz ~ 100 kHz

What is Magnetoresistance

Magnetoresistance effect(AMR)

θθθ 2cos2

12sin12cos(

22 minusminus+∆asymp∆ xxxmx hhhRR

32 minusasymp∆ ρρ New effect GMR CMR and GMI

10 ge∆ ρρ

Two bridge configuration for

rotational angle measurement

measurement angle more than 180o

자동차 Engine Management System

Inductive and Eddy Current

Sensors Excited by Permanent Magnets

tNtU dd)( φsdotminus=

construction of an inductive

sensor (courtesy VDO Adolf sensor (courtesy VDO Adolf

Schindling AG)

1) constant socket

2) terminal package

3) permanent magnet

4) cap

5) soft magnetic core

6) coil

7) plate

8) blade connector

γγ

Sensor with yoke Change in the magnetic flux with

varying air gap Continuous lines

minimum air gap dashed lines

maximum air gap

C-shaped sensor

Sensor with radially

magnetized

permanent magnet

Signal Conditioning

Output voltage U of a DC-excited sensor with permanent

magnets when a single iron object passes by

Schematic electrical diagram of an inductive sensor

Linear Variable Differential Transformer

AC-Excited Sensors for Linear Movement

Principle of construction of an LVDT

Electrical circuit of an LVDT

tIMtNU dd dd sdotminus=sdotminus= φ

tIMtIMUUU dd dd 1212 sdotminussdot=minus=

tIMMU dd)( 12 sdotminus=

)(12 xMMMM =minus=

tIxMU dd)( sdot= tI

UxM

dd)( =

Signal Conditioning

power supply

carrier gen

autoampcontrol

LVDTcarrieramp

demod-ulator

phase

shifter

power supply

carrier gen

passivedemod-ulator

LVDTDCamp

Block diagram of a carrier amplifier system

Block diagram of a DC amplifier system

Variable Inductive Sensors

Principle of construction

of the VLP sensor

Principle of a bridge

circuit

lANL r 20 sdotsdotsdot= micromicro

21 BA UUU minus=

21)i(ii( 211 minus+sdot= LLLUU BA ωωω

)21))()((( minus∆minus+∆+∆+sdot= LLLLLLUU BA

)212)(( minus∆+sdot= LLLUU )212)(( minus∆+sdot= LLLUU BA

LLUU BA 21 ∆sdotsdot=

llLL ∆sdot=∆ d d

llLLUU BA ∆sdotsdot= d d)2(1

Applications and Properties

Principle of a construction of a force transducer

(courtesy Hottinger Baldwin Messtechnik)

Vibrationacceleration sensor

Signal Conditioning

Schematic electrical diagram of a force transducer connected with an

amplifier (courtesy Hottinger Baldwin Messtechnik GmbH)

Variable Gap Sensors

)( FeFe2

0 LLllANL micromicromicro +sdotsdot=

FeFe2

0max lANL sdotsdotsdot= micromicro

Construction of a variable gap sensor

Characteristic of a variable gap sensor

Construction of a differential

cross-anchor sensor

Output voltage U versus core

position x plusmn a limits of the

linear rage

Applications of differential cross-anchor sensors

AC-excited Sensors for Rotary Movements

Principle of construction of a synchro

α cos10 sdotsdot= UKU y

)120-( cos10 degsdotsdot= αUKU z

)240-( cos10 degsdotsdot= αUKU x

)120-( sin3100 degsdotsdotsdot=minus= αKUUUU yxyx

)240-( sin3100 degsdotsdotsdot=minus= αKUUUU zyzy

α sin3100 sdotsdotsdot=minus= KUUUU xzxz

Application to the Torque Sensor

Principle of construction of a torque-type synchro

Torque versus angular

difference

)( sin~ rt αα minussdotKM

)( cos~ rt1r αα minussdotUU

Principle of construction of a control-type sensor

Output voltage versus

angular difference

Principle of construction of a differential sychro

Eddy Current Sensors

tBE dd curl minus=JH = curl

0 div =BH(H)B sdot= micro

E(E)J sdot= σ

A B curl= A B curl=

tdd- A E =

)dd( tAJ minus= σ

tdd curl curl AA σmicro minus=

AA) σωmicro iminus= curl )(curl(1

AA) σωmicro i=∆)((1

Eddy Current Tachometer

Construction of a speedometer (courtesy VDO Adolf Schinding AG) 1) spindle 2) bearing

3) holding spring 4) iron yoke 5) eddy current cup 6) shaft of the magnet 7) support of

the magnet 8) temperature compensation 9) permanent magnet 10) torsion spring

Proximity Sensors

Schematic diagram of a proximity sensor

Output current of a proximity switch versus distance

Inductive Flowmeters

)( Btimessdot= υqF

EqF sdot=BE times=υ

)(ds Btimes== υEU )(ds Btimes== υEU

)( Bd timessdot= υU

Bsdotsdotsdot= υdKU

Development of magnetic phase detection

sensor for steam generator tube

Dirac Son1 Kwan-Sang Ryu2 Duck-Gun Park3

1Hannam University Daejeon Rep of Korea2Korea Research Institute of Standards and Science Daejeon Rep of Korea3KoreaAtomic Energy Research Institute Daejeon Rep of Korea

Introduction

The layout of pressurized water reactor (PWR) components

Primary side Secondary side (non-radioactive side)(radioactive side)

The Structure of SG(Steam Generator)(degradation mechanism)

Secondary SidePrimary Side

SCC

A B

A-B

Steam outlet

Anti-vibration

SCC

Fretting

Wall thinning

IGA

U-bend

In commercial power plants SG- height up to 21 m - weight up to 800 tons - 2~4 sets of SG were installed - SG can contain from 3000 to

16000 tubes each about 20 mmin diameter

Primary coolant outlet Primary coolant inlet

Anti-vibrationbars

Tubesupportplate

Tubesheet

IGA

SCC

Pitting

SCC

Inside Tubesheet

Top of Tubesheet

by SSHwang of KAERI

Denting

Sludge pile

in diameter

The SGT is made of nickel basedInconel alloy which is composed of 75 Ni 165Cr and 815Fe

-Degradation mechanism corrosion pitting denting inter granular attack

-Inspection Eddy current Testing(ECT)

Permeability Variation Clusters (PVC)

(Ferro-magnetic phase)

-005

000

005

010

015

m (emug)

1-1

-002

000

002

004

006

008

m (emug)

1-2

-1000 -500 0 500 1000

-015

-010

-005

H ( Am )

-1000 -500 0 500 1000

-006

-004

-002

H ( Am )

The hystresis loop in the fragment of PVC parts of Kori-1 retired SG tube

-004

-002

000

002

004

006

M (emug)

Inconel 600 tested at RT

under tensile stress

1 2 3

4 5 6

7 8 9-004

-002

000

002

004

006

M(emug)

Inconel 600 Heat treated at

602 oC under tensile stress

1 2 3

How can we detect magnetic phase

(PVC)selectively from the flaws in SGT

-3000 -2000 -1000 0 1000 2000 3000

-006

H (Oe)

7 8 9

10 11 12

-3000 -2000 -1000 0 1000 2000 3000

-006

-004

H(Oe)

4 5 6

7 8 9

The hysteresis loop of the tensile tested specimen at room temperature (a) and tensile tested at high temperature (b)

The magnetic phase can be created under the high temperature andpressure conditions which is correspond to the stress corrosion crackingin the SG tube in the NPP(Bruemmer SM Charlot LA amp Henager CH (1988) Corrosion 782)

Principle of ECT

If we can separate magnetic phase selectively from the

flaws using magnetic sensor the reliability of EC in SGT

inspection will be greatly enhanced

Structure of the permeability

sensor

Dimension and photograph of U-shape

sensing yoke

Design of Magnetic Sensor for PVC

sensor sensing yoke

Photograph of the completed sensor front side (above) and rear side (bottom)

R11R12

R10

R8

R6

R9

R13

R7

R14

C18

1 n

C17

C20

C21

D2

DIODE

SIN COS

-

+

U-2A

4

13

2

-

+

U-2B

75

6

8

-

+

U-3A

13

2

8

+5VC19

104

+5V

Schematic diagram of the sensor system

Electronic Circuit of Magnetic Sensor

R20

R

R21

R

-

+

U5AD797

3

26

74

U6

D1

S12

GND3

+VCC4VCC5

IN6

-VCC7

S28

C41

R13

R26

R18

R25

R2210 Ω

R16

R14

R17

10 k

R15

R27

R32

R28

R33

R29

R34

5 k

R30

C29

C37

104

C32473

C39473C40

104

C33

104

C21

104C23

104

C25

104

C26

104

C30

104

C31

104

C35

104

C36

104

C27

104

C28

104

C34

104

C38

104

D3

DIODE

L1

1

2

L2

1

2

L3

1

2

4

-

+

U-4A

4

13

2

-

+

U-4B

75

6

8

-

+

U-5A

4

13

2

-

+

U-5B

75

6

8

-

+

U-6A

4

13

2

-

+

U-6B

75

6

8

C22

104

-5V

+5V

+5V

+5V

+5V

+5V

+5V

U7

D1

S12

GND3

+VCC4

VCC5

IN6

-VCC7

S28

+5V

-5V

-5V

-5V

-5V

-5V

-5V

-5V

-5V

R19

R24

R

R23

R

C24

OUT(X)

OUT(Y)

R1

20 kR210 k

R3

20 kR410 k

C1

104

C8

104

REF43

OUT(X)

OUT(Y)

REF43

U2

+Vcc1

CH02

CH13

CH24

CH35

COMM6

SHDN7

Vref8

+Vcc9

GND10

GND11

DOUT12BUSY13DIN14CS15

DIN16

-

+

U-1A

13

2

8

-

+

U-1B

4

75

6

C410 uF

C5104

DOUT

C210uF

C6104

C3104

DCLK

C7104

DIN

C10

01uF

CS

BUSY

C14 10uF

J1

CON6

123456

D1

DIODE

R5

47K

C9

10uF

C1310uF

Y1

OSC

OUT3

GND2

VCC4

U3

RSTVPP1

GND10

VCC20

XTAL15

XTAL24

P10AIN012P11AIN113P1214P1315P1416P1517P1618P1719

P30RXD2

P31TXD3

P32INT06

P33INT17

P34T08

P35T19

P3711

U4

C1+1

C1-3

C2+4

C2-5

VCC16

GND15

V+2

V-6

R1OUT12

R2OUT9

T1IN11

T2IN10

R1IN13

R2IN8

T1OUT14

T2OUT7

C12 10uF

C16

01uF

C15 10uF

C11

01uF

-5V

+5V

+5V

+5V

+5V

+5V

+5V

+5V

RST

OSC

OSC

RST

DCLKCSDINBUSYDOUT

U1

IN2

GND

4

OUT6

TEMP3

TRIM5

-5V

+5V

Electronic circuit diagram of the magnetic sensor

Photograph of the completed measuring system data acquisition

software in PC and probe scanning system

Experimental Setup for Magnetic Sensor

Reference material Scanning System Software LabVIEW

Reference Material (1) Normal defects and PVCs

Longitudinal and transverse defects

Def W L D Remarks

1 02 500 0213 (20 ) Inner defects

2 02 500 0427 (40 )

3 02 500 0213 (20 )Outer defectsPVC(1018)4 02 500 0427 (40 )

5 02 500 0639 (60 )

6 02 500 0852 (80 )

7 02 500 0639 (60 ) Inner defects

8 02 500 0852 (80 )

- 1 and 2 are inner defects

- 345 and 6 are outer defects with PVC

- 7 and 8 are inner defects

PVC

PVC

Defect Defect

For longitudinal defects and PVC For circumferential defects and PVC

ECT is very difficult to detect circumferential defects

We can distinguish PVCs and defects and longitudinal and circumferential defects

Flux-gate Magnetometer

One core sensor Two core sensor

3-축 flux-gate Magnetometer의 계략도

Sensorpia Co

pro

cess

or(

AV

R)

Sensor 1

RS422

Interface

Mic

ro-p

roce

ssor(

AV

R)

Sensor 2

Sensor 3

Interface

조립된 마그네토미터의 사진

Sensorpia Co

Analog PCB

Digital PCB

Sensorpia Co선형도(linearity)

10

20

30

40

50

60

y-axis

Magnetometer Output (microT)

-60 -50 -40 -30 -20 -10 0 10 20 30 40 50 60

-60

-50

-40

-30

-20

-10

0

10

Y-axis y=099946 x+0015STD 106E-4

Magnetometer Output (

Applied Magnetic Field (microT)

마그네토미터의 noise 특성 Sensorpia Co

1

10

100

y-axis

Magnetometer noise (nT)

0 1 2 3 4 5 6

1E-4

1E-3

001

01

Magnetometer noise (nT)

Frequency (Hz)

Magnetometer for KoDSAT

-150 -100 -50 0 50 100 150

-15

-10

-5

0

5

10

15

Magnetic Moment (Am

2)

Current (mA)

After Thermal Cycle Test

Measured

Resistance 193 ohm

Photograph of Magnetic torquer

Photograph of KoDSAT

Photograph of

3-axis Fluxgate

Magnetometer

Photograph of Magnetic torquer

Application of magnetometer

Moon magnetic fieldmeasurement

Telescope with direction indication

Joule Effect (Magnetostriction)

ϕ2cosel

l=

∆

0=∆

+∆

+∆

b

b

a

a

l

l

Actuator using Terfenol-D

00

05

10

B (T)

800

1000

1200

1400

1600

Magnetostriction (ppm)

-100 -50 0 50 100

-10

-05

00

B (T)

H (kAm)

2 MPa

4 MPa

6 MPa

8 MPa

10 MPa

12 MPa

-100 -50 0 50 100

-200

0

200

400

600

Magnetostriction (ppm)

H (kAm)

2 MPa

4 MPa

6 MPa

8 MPa

10 MPa

12 MPa

600

700

800

900

1000

-4 -3 -2 -1 0 1 2 3 4

0

10

20

30

40

50

60

Displacement (m

icro meter)

I (A)

FIELD

9 kAm

12 kAm

16 kAm

20 kAm

24 kAm

38 kAm

-50 -40 -30 -20 -10 0 10 20 30 40 50

-100

0

100

200

300

400

500

L (PPM)

H (kAm)

9 kAm

12 kAm

16 kAm

20 kAm

24 kAm

38 kAm

Magnetostrictive displacement sensor

Hysteresis loops under

tensile stress σ

(a) Crystalline 68 NiFe

λs = +25 10-6

(b) crystalline pure Ni λs

= -35 10-6

Villari Effect ( Inverse of Joule Effect)

= -35 10-6

(c) amorphous Co-based

alloy

λs = -35 10-6

ϕσλ 2sin2

3sdotsdot= smeE

γ

Permeability depending on the stress

σλmicromicro

1

3

2

Y

J

so

s

r =

γ

Calculated magnetization curves under stress

Variation of magnetization curve by an applied

tensile force (Co-based amorphous alloy)

Alloy Requirement

Materials for magnetoelastic sensors

Why amorphous magnetic materials are important

Stress-strain curves of several materials

Coercivity and hardness of several materials

Principles of magnetoelastic sensors

Non-contact torque sensor

Principle of cross torductor torque

sensor and flux pattern of sensor

poles on the surface of a shaft

a) without and b)with torsional load

Equivalent magnetic circuit of

cross type torque sensor

Helices of principal tensile and compressive stress on the surface of

a shaft subjected to torsion [32] Correlated changes of permeability

are detected by four-branch yoke system with sensing coils 123

and 4 and a common excitation pole

Examples of torque sensors

Four-branch type torque sensor

heads Pole structures realized

by commercial multi-pole

ferrites 14 and 18 min in

diameter (diameter of sensor

h e a d 1 7 a n d 2 4 m m

respectively) respectively)

Principle of Ring Torductor torque transducer

(a b) Physical structure (c) evolution of the

shaft surface under the transducer poles A and BRing torductor for measuring

torque on ship propeller shafts

(shaft diameter ca 500 mm)

(Courtesy ASEA Brown

Boveri AG)

Principal designs of coaxial torque sensors

Schematic diagram of data processing

electronics of a torque sensor

Extensometer (a) Construction of strain sensing element using

amorphous ribbon wound core (b) configuration of lumped

windings

∆E effect of an amorphous FeNi-based

alloy (Fe40 Ni38 Mo4 B18) Hs saturation

field

Magnetically tunable delay line

Torque Sensors using Amorphous wire

Sixtus tonk효과(large Barkhausen효과)

Hysteresis loops of a Wiegand wire for different reset fields

Curie 온도 및Hopkinson효과

Relation between normalised

saturation polarisation and

normalised Curie temperature

Permeability of a Mn-Zn ferrite as

a function of temperature and field

strength

Conclusions

1) Magnetic sensor 는 자동차 공장자동화 항공우주 및 군사용으로많이 사용되고 있다

2) 새로운 소재개발은 자기센서의 성능개발에 직접적인 영향을 준다2) 새로운 소재개발은 자기센서의 성능개발에 직접적인 영향을 준다

3) 센서의 개발을 위해서는 다양한 전공지식이 요구된다

(물리학 재료공학 기계공학 전자공학)

4) 센서분야가 고부가가치를 창출하는 부품사업이다

5) 핵심부품을 생산하는 중소기업의 item으로도 적절하다

25

30

35

40

45

50

Output voltage V

Current sensor(Open loop type)

Temp 25C

400A model

+400 ~ -400A

SD 000128

Linearity 003

Linearity of the sensor

Characteristics of the Current Sensors

1000A 10 V power supply

-500 -400 -300 -200 -100 0 100 200 300 400 500

00

05

10

15

20

Output voltage V

current A

Temperature 25Linearity 003

Measuring range -400A ~ +400A

1000A Electronic Load

-3

0

3

6

9

12

15

18

dB

Current sensor

DV2 PCB 24pF

40Aturns

Frequency bandwidth

Gain bandwidth 3 MHz

Current 10 A

Temperature 25

Frequency bandwidth 100 kHz

Sensor output voltage vs frequency

at applied current of 40 Aturns

1 10 100

-18

-15

-12

-9

-6

Frequency kHz 측정온도 25

주파수특성 30kHz 이상(3dB 기준)

측정전류 40Aturns(4A 10턴)

측정주파수 100Hz ~ 100kHz

Temperature 25Current 40Aturns

Frequency range 100 Hz ~ 100 kHz

What is Magnetoresistance

Magnetoresistance effect(AMR)

θθθ 2cos2

12sin12cos(

22 minusminus+∆asymp∆ xxxmx hhhRR

32 minusasymp∆ ρρ New effect GMR CMR and GMI

10 ge∆ ρρ

Two bridge configuration for

rotational angle measurement

measurement angle more than 180o

자동차 Engine Management System

Inductive and Eddy Current

Sensors Excited by Permanent Magnets

tNtU dd)( φsdotminus=

construction of an inductive

sensor (courtesy VDO Adolf sensor (courtesy VDO Adolf

Schindling AG)

1) constant socket

2) terminal package

3) permanent magnet

4) cap

5) soft magnetic core

6) coil

7) plate

8) blade connector

γγ

Sensor with yoke Change in the magnetic flux with

varying air gap Continuous lines

minimum air gap dashed lines

maximum air gap

C-shaped sensor

Sensor with radially

magnetized

permanent magnet

Signal Conditioning

Output voltage U of a DC-excited sensor with permanent

magnets when a single iron object passes by

Schematic electrical diagram of an inductive sensor

Linear Variable Differential Transformer

AC-Excited Sensors for Linear Movement

Principle of construction of an LVDT

Electrical circuit of an LVDT

tIMtNU dd dd sdotminus=sdotminus= φ

tIMtIMUUU dd dd 1212 sdotminussdot=minus=

tIMMU dd)( 12 sdotminus=

)(12 xMMMM =minus=

tIxMU dd)( sdot= tI

UxM

dd)( =

Signal Conditioning

power supply

carrier gen

autoampcontrol

LVDTcarrieramp

demod-ulator

phase

shifter

power supply

carrier gen

passivedemod-ulator

LVDTDCamp

Block diagram of a carrier amplifier system

Block diagram of a DC amplifier system

Variable Inductive Sensors

Principle of construction

of the VLP sensor

Principle of a bridge

circuit

lANL r 20 sdotsdotsdot= micromicro

21 BA UUU minus=

21)i(ii( 211 minus+sdot= LLLUU BA ωωω

)21))()((( minus∆minus+∆+∆+sdot= LLLLLLUU BA

)212)(( minus∆+sdot= LLLUU )212)(( minus∆+sdot= LLLUU BA

LLUU BA 21 ∆sdotsdot=

llLL ∆sdot=∆ d d

llLLUU BA ∆sdotsdot= d d)2(1

Applications and Properties

Principle of a construction of a force transducer

(courtesy Hottinger Baldwin Messtechnik)

Vibrationacceleration sensor

Signal Conditioning

Schematic electrical diagram of a force transducer connected with an

amplifier (courtesy Hottinger Baldwin Messtechnik GmbH)

Variable Gap Sensors

)( FeFe2

0 LLllANL micromicromicro +sdotsdot=

FeFe2

0max lANL sdotsdotsdot= micromicro

Construction of a variable gap sensor

Characteristic of a variable gap sensor

Construction of a differential

cross-anchor sensor

Output voltage U versus core

position x plusmn a limits of the

linear rage

Applications of differential cross-anchor sensors

AC-excited Sensors for Rotary Movements

Principle of construction of a synchro

α cos10 sdotsdot= UKU y

)120-( cos10 degsdotsdot= αUKU z

)240-( cos10 degsdotsdot= αUKU x

)120-( sin3100 degsdotsdotsdot=minus= αKUUUU yxyx

)240-( sin3100 degsdotsdotsdot=minus= αKUUUU zyzy

α sin3100 sdotsdotsdot=minus= KUUUU xzxz

Application to the Torque Sensor

Principle of construction of a torque-type synchro

Torque versus angular

difference

)( sin~ rt αα minussdotKM

)( cos~ rt1r αα minussdotUU

Principle of construction of a control-type sensor

Output voltage versus

angular difference

Principle of construction of a differential sychro

Eddy Current Sensors

tBE dd curl minus=JH = curl

0 div =BH(H)B sdot= micro

E(E)J sdot= σ

A B curl= A B curl=

tdd- A E =

)dd( tAJ minus= σ

tdd curl curl AA σmicro minus=

AA) σωmicro iminus= curl )(curl(1

AA) σωmicro i=∆)((1

Eddy Current Tachometer

Construction of a speedometer (courtesy VDO Adolf Schinding AG) 1) spindle 2) bearing

3) holding spring 4) iron yoke 5) eddy current cup 6) shaft of the magnet 7) support of

the magnet 8) temperature compensation 9) permanent magnet 10) torsion spring

Proximity Sensors

Schematic diagram of a proximity sensor

Output current of a proximity switch versus distance

Inductive Flowmeters

)( Btimessdot= υqF

EqF sdot=BE times=υ

)(ds Btimes== υEU )(ds Btimes== υEU

)( Bd timessdot= υU

Bsdotsdotsdot= υdKU

Development of magnetic phase detection

sensor for steam generator tube

Dirac Son1 Kwan-Sang Ryu2 Duck-Gun Park3

1Hannam University Daejeon Rep of Korea2Korea Research Institute of Standards and Science Daejeon Rep of Korea3KoreaAtomic Energy Research Institute Daejeon Rep of Korea

Introduction

The layout of pressurized water reactor (PWR) components

Primary side Secondary side (non-radioactive side)(radioactive side)

The Structure of SG(Steam Generator)(degradation mechanism)

Secondary SidePrimary Side

SCC

A B

A-B

Steam outlet

Anti-vibration

SCC

Fretting

Wall thinning

IGA

U-bend

In commercial power plants SG- height up to 21 m - weight up to 800 tons - 2~4 sets of SG were installed - SG can contain from 3000 to

16000 tubes each about 20 mmin diameter

Primary coolant outlet Primary coolant inlet

Anti-vibrationbars

Tubesupportplate

Tubesheet

IGA

SCC

Pitting

SCC

Inside Tubesheet

Top of Tubesheet

by SSHwang of KAERI

Denting

Sludge pile

in diameter

The SGT is made of nickel basedInconel alloy which is composed of 75 Ni 165Cr and 815Fe

-Degradation mechanism corrosion pitting denting inter granular attack

-Inspection Eddy current Testing(ECT)

Permeability Variation Clusters (PVC)

(Ferro-magnetic phase)

-005

000

005

010

015

m (emug)

1-1

-002

000

002

004

006

008

m (emug)

1-2

-1000 -500 0 500 1000

-015

-010

-005

H ( Am )

-1000 -500 0 500 1000

-006

-004

-002

H ( Am )

The hystresis loop in the fragment of PVC parts of Kori-1 retired SG tube

-004

-002

000

002

004

006

M (emug)

Inconel 600 tested at RT

under tensile stress

1 2 3

4 5 6

7 8 9-004

-002

000

002

004

006

M(emug)

Inconel 600 Heat treated at

602 oC under tensile stress

1 2 3

How can we detect magnetic phase

(PVC)selectively from the flaws in SGT

-3000 -2000 -1000 0 1000 2000 3000

-006

H (Oe)

7 8 9

10 11 12

-3000 -2000 -1000 0 1000 2000 3000

-006

-004

H(Oe)

4 5 6

7 8 9

The hysteresis loop of the tensile tested specimen at room temperature (a) and tensile tested at high temperature (b)

The magnetic phase can be created under the high temperature andpressure conditions which is correspond to the stress corrosion crackingin the SG tube in the NPP(Bruemmer SM Charlot LA amp Henager CH (1988) Corrosion 782)

Principle of ECT

If we can separate magnetic phase selectively from the

flaws using magnetic sensor the reliability of EC in SGT

inspection will be greatly enhanced

Structure of the permeability

sensor

Dimension and photograph of U-shape

sensing yoke

Design of Magnetic Sensor for PVC

sensor sensing yoke

Photograph of the completed sensor front side (above) and rear side (bottom)

R11R12

R10

R8

R6

R9

R13

R7

R14

C18

1 n

C17

C20

C21

D2

DIODE

SIN COS

-

+

U-2A

4

13

2

-

+

U-2B

75

6

8

-

+

U-3A

13

2

8

+5VC19

104

+5V

Schematic diagram of the sensor system

Electronic Circuit of Magnetic Sensor

R20

R

R21

R

-

+

U5AD797

3

26

74

U6

D1

S12

GND3

+VCC4VCC5

IN6

-VCC7

S28

C41

R13

R26

R18

R25

R2210 Ω

R16

R14

R17

10 k

R15

R27

R32

R28

R33

R29

R34

5 k

R30

C29

C37

104

C32473

C39473C40

104

C33

104

C21

104C23

104

C25

104

C26

104

C30

104

C31

104

C35

104

C36

104

C27

104

C28

104

C34

104

C38

104

D3

DIODE

L1

1

2

L2

1

2

L3

1

2

4

-

+

U-4A

4

13

2

-

+

U-4B

75

6

8

-

+

U-5A

4

13

2

-

+

U-5B

75

6

8

-

+

U-6A

4

13

2

-

+

U-6B

75

6

8

C22

104

-5V

+5V

+5V

+5V

+5V

+5V

+5V

U7

D1

S12

GND3

+VCC4

VCC5

IN6

-VCC7

S28

+5V

-5V

-5V

-5V

-5V

-5V

-5V

-5V

-5V

R19

R24

R

R23

R

C24

OUT(X)

OUT(Y)

R1

20 kR210 k

R3

20 kR410 k

C1

104

C8

104

REF43

OUT(X)

OUT(Y)

REF43

U2

+Vcc1

CH02

CH13

CH24

CH35

COMM6

SHDN7

Vref8

+Vcc9

GND10

GND11

DOUT12BUSY13DIN14CS15

DIN16

-

+

U-1A

13

2

8

-

+

U-1B

4

75

6

C410 uF

C5104

DOUT

C210uF

C6104

C3104

DCLK

C7104

DIN

C10

01uF

CS

BUSY

C14 10uF

J1

CON6

123456

D1

DIODE

R5

47K

C9

10uF

C1310uF

Y1

OSC

OUT3

GND2

VCC4

U3

RSTVPP1

GND10

VCC20

XTAL15

XTAL24

P10AIN012P11AIN113P1214P1315P1416P1517P1618P1719

P30RXD2

P31TXD3

P32INT06

P33INT17

P34T08

P35T19

P3711

U4

C1+1

C1-3

C2+4

C2-5

VCC16

GND15

V+2

V-6

R1OUT12

R2OUT9

T1IN11

T2IN10

R1IN13

R2IN8

T1OUT14

T2OUT7

C12 10uF

C16

01uF

C15 10uF

C11

01uF

-5V

+5V

+5V

+5V

+5V

+5V

+5V

+5V

RST

OSC

OSC

RST

DCLKCSDINBUSYDOUT

U1

IN2

GND

4

OUT6

TEMP3

TRIM5

-5V

+5V

Electronic circuit diagram of the magnetic sensor

Photograph of the completed measuring system data acquisition

software in PC and probe scanning system

Experimental Setup for Magnetic Sensor

Reference material Scanning System Software LabVIEW

Reference Material (1) Normal defects and PVCs

Longitudinal and transverse defects

Def W L D Remarks

1 02 500 0213 (20 ) Inner defects

2 02 500 0427 (40 )

3 02 500 0213 (20 )Outer defectsPVC(1018)4 02 500 0427 (40 )

5 02 500 0639 (60 )

6 02 500 0852 (80 )

7 02 500 0639 (60 ) Inner defects

8 02 500 0852 (80 )

- 1 and 2 are inner defects

- 345 and 6 are outer defects with PVC

- 7 and 8 are inner defects

PVC

PVC

Defect Defect

For longitudinal defects and PVC For circumferential defects and PVC

ECT is very difficult to detect circumferential defects

We can distinguish PVCs and defects and longitudinal and circumferential defects

Flux-gate Magnetometer

One core sensor Two core sensor

3-축 flux-gate Magnetometer의 계략도

Sensorpia Co

pro

cess

or(

AV

R)

Sensor 1

RS422

Interface

Mic

ro-p

roce

ssor(

AV

R)

Sensor 2

Sensor 3

Interface

조립된 마그네토미터의 사진

Sensorpia Co

Analog PCB

Digital PCB

Sensorpia Co선형도(linearity)

10

20

30

40

50

60

y-axis

Magnetometer Output (microT)

-60 -50 -40 -30 -20 -10 0 10 20 30 40 50 60

-60

-50

-40

-30

-20

-10

0

10

Y-axis y=099946 x+0015STD 106E-4

Magnetometer Output (

Applied Magnetic Field (microT)

마그네토미터의 noise 특성 Sensorpia Co

1

10

100

y-axis

Magnetometer noise (nT)

0 1 2 3 4 5 6

1E-4

1E-3

001

01

Magnetometer noise (nT)

Frequency (Hz)

Magnetometer for KoDSAT

-150 -100 -50 0 50 100 150

-15

-10

-5

0

5

10

15

Magnetic Moment (Am

2)

Current (mA)

After Thermal Cycle Test

Measured

Resistance 193 ohm

Photograph of Magnetic torquer

Photograph of KoDSAT

Photograph of

3-axis Fluxgate

Magnetometer

Photograph of Magnetic torquer

Application of magnetometer

Moon magnetic fieldmeasurement

Telescope with direction indication

Joule Effect (Magnetostriction)

ϕ2cosel

l=

∆

0=∆

+∆

+∆

b

b

a

a

l

l

Actuator using Terfenol-D

00

05

10

B (T)

800

1000

1200

1400

1600

Magnetostriction (ppm)

-100 -50 0 50 100

-10

-05

00

B (T)

H (kAm)

2 MPa

4 MPa

6 MPa

8 MPa

10 MPa

12 MPa

-100 -50 0 50 100

-200

0

200

400

600

Magnetostriction (ppm)

H (kAm)

2 MPa

4 MPa

6 MPa

8 MPa

10 MPa

12 MPa

600

700

800

900

1000

-4 -3 -2 -1 0 1 2 3 4

0

10

20

30

40

50

60

Displacement (m

icro meter)

I (A)

FIELD

9 kAm

12 kAm

16 kAm

20 kAm

24 kAm

38 kAm

-50 -40 -30 -20 -10 0 10 20 30 40 50

-100

0

100

200

300

400

500

L (PPM)

H (kAm)

9 kAm

12 kAm

16 kAm

20 kAm

24 kAm

38 kAm

Magnetostrictive displacement sensor

Hysteresis loops under

tensile stress σ

(a) Crystalline 68 NiFe

λs = +25 10-6

(b) crystalline pure Ni λs

= -35 10-6

Villari Effect ( Inverse of Joule Effect)

= -35 10-6

(c) amorphous Co-based

alloy

λs = -35 10-6

ϕσλ 2sin2

3sdotsdot= smeE

γ

Permeability depending on the stress

σλmicromicro

1

3

2

Y

J

so

s

r =

γ

Calculated magnetization curves under stress

Variation of magnetization curve by an applied

tensile force (Co-based amorphous alloy)

Alloy Requirement

Materials for magnetoelastic sensors

Why amorphous magnetic materials are important

Stress-strain curves of several materials

Coercivity and hardness of several materials

Principles of magnetoelastic sensors

Non-contact torque sensor

Principle of cross torductor torque

sensor and flux pattern of sensor

poles on the surface of a shaft

a) without and b)with torsional load

Equivalent magnetic circuit of

cross type torque sensor

Helices of principal tensile and compressive stress on the surface of

a shaft subjected to torsion [32] Correlated changes of permeability

are detected by four-branch yoke system with sensing coils 123

and 4 and a common excitation pole

Examples of torque sensors

Four-branch type torque sensor

heads Pole structures realized

by commercial multi-pole

ferrites 14 and 18 min in

diameter (diameter of sensor

h e a d 1 7 a n d 2 4 m m

respectively) respectively)

Principle of Ring Torductor torque transducer

(a b) Physical structure (c) evolution of the

shaft surface under the transducer poles A and BRing torductor for measuring

torque on ship propeller shafts

(shaft diameter ca 500 mm)

(Courtesy ASEA Brown

Boveri AG)

Principal designs of coaxial torque sensors

Schematic diagram of data processing

electronics of a torque sensor

Extensometer (a) Construction of strain sensing element using

amorphous ribbon wound core (b) configuration of lumped

windings

∆E effect of an amorphous FeNi-based

alloy (Fe40 Ni38 Mo4 B18) Hs saturation

field

Magnetically tunable delay line

Torque Sensors using Amorphous wire

Sixtus tonk효과(large Barkhausen효과)

Hysteresis loops of a Wiegand wire for different reset fields

Curie 온도 및Hopkinson효과

Relation between normalised

saturation polarisation and

normalised Curie temperature

Permeability of a Mn-Zn ferrite as

a function of temperature and field

strength

Conclusions

1) Magnetic sensor 는 자동차 공장자동화 항공우주 및 군사용으로많이 사용되고 있다

2) 새로운 소재개발은 자기센서의 성능개발에 직접적인 영향을 준다2) 새로운 소재개발은 자기센서의 성능개발에 직접적인 영향을 준다

3) 센서의 개발을 위해서는 다양한 전공지식이 요구된다

(물리학 재료공학 기계공학 전자공학)

4) 센서분야가 고부가가치를 창출하는 부품사업이다

5) 핵심부품을 생산하는 중소기업의 item으로도 적절하다

-3

0

3

6

9

12

15

18

dB

Current sensor

DV2 PCB 24pF

40Aturns

Frequency bandwidth

Gain bandwidth 3 MHz

Current 10 A

Temperature 25

Frequency bandwidth 100 kHz

Sensor output voltage vs frequency

at applied current of 40 Aturns

1 10 100

-18

-15

-12

-9

-6

Frequency kHz 측정온도 25

주파수특성 30kHz 이상(3dB 기준)

측정전류 40Aturns(4A 10턴)

측정주파수 100Hz ~ 100kHz

Temperature 25Current 40Aturns

Frequency range 100 Hz ~ 100 kHz

What is Magnetoresistance

Magnetoresistance effect(AMR)

θθθ 2cos2

12sin12cos(

22 minusminus+∆asymp∆ xxxmx hhhRR

32 minusasymp∆ ρρ New effect GMR CMR and GMI

10 ge∆ ρρ

Two bridge configuration for

rotational angle measurement

measurement angle more than 180o

자동차 Engine Management System

Inductive and Eddy Current

Sensors Excited by Permanent Magnets

tNtU dd)( φsdotminus=

construction of an inductive

sensor (courtesy VDO Adolf sensor (courtesy VDO Adolf

Schindling AG)

1) constant socket

2) terminal package

3) permanent magnet

4) cap

5) soft magnetic core

6) coil

7) plate

8) blade connector

γγ

Sensor with yoke Change in the magnetic flux with

varying air gap Continuous lines

minimum air gap dashed lines

maximum air gap

C-shaped sensor

Sensor with radially

magnetized

permanent magnet

Signal Conditioning

Output voltage U of a DC-excited sensor with permanent

magnets when a single iron object passes by

Schematic electrical diagram of an inductive sensor

Linear Variable Differential Transformer

AC-Excited Sensors for Linear Movement

Principle of construction of an LVDT

Electrical circuit of an LVDT

tIMtNU dd dd sdotminus=sdotminus= φ

tIMtIMUUU dd dd 1212 sdotminussdot=minus=

tIMMU dd)( 12 sdotminus=

)(12 xMMMM =minus=

tIxMU dd)( sdot= tI

UxM

dd)( =

Signal Conditioning

power supply

carrier gen

autoampcontrol

LVDTcarrieramp

demod-ulator

phase

shifter

power supply

carrier gen

passivedemod-ulator

LVDTDCamp

Block diagram of a carrier amplifier system

Block diagram of a DC amplifier system

Variable Inductive Sensors

Principle of construction

of the VLP sensor

Principle of a bridge

circuit

lANL r 20 sdotsdotsdot= micromicro

21 BA UUU minus=

21)i(ii( 211 minus+sdot= LLLUU BA ωωω

)21))()((( minus∆minus+∆+∆+sdot= LLLLLLUU BA

)212)(( minus∆+sdot= LLLUU )212)(( minus∆+sdot= LLLUU BA

LLUU BA 21 ∆sdotsdot=

llLL ∆sdot=∆ d d

llLLUU BA ∆sdotsdot= d d)2(1

Applications and Properties

Principle of a construction of a force transducer

(courtesy Hottinger Baldwin Messtechnik)

Vibrationacceleration sensor

Signal Conditioning

Schematic electrical diagram of a force transducer connected with an

amplifier (courtesy Hottinger Baldwin Messtechnik GmbH)

Variable Gap Sensors

)( FeFe2

0 LLllANL micromicromicro +sdotsdot=

FeFe2

0max lANL sdotsdotsdot= micromicro

Construction of a variable gap sensor

Characteristic of a variable gap sensor

Construction of a differential

cross-anchor sensor

Output voltage U versus core

position x plusmn a limits of the

linear rage

Applications of differential cross-anchor sensors

AC-excited Sensors for Rotary Movements

Principle of construction of a synchro

α cos10 sdotsdot= UKU y

)120-( cos10 degsdotsdot= αUKU z

)240-( cos10 degsdotsdot= αUKU x

)120-( sin3100 degsdotsdotsdot=minus= αKUUUU yxyx

)240-( sin3100 degsdotsdotsdot=minus= αKUUUU zyzy

α sin3100 sdotsdotsdot=minus= KUUUU xzxz

Application to the Torque Sensor

Principle of construction of a torque-type synchro

Torque versus angular

difference

)( sin~ rt αα minussdotKM

)( cos~ rt1r αα minussdotUU

Principle of construction of a control-type sensor

Output voltage versus

angular difference

Principle of construction of a differential sychro

Eddy Current Sensors

tBE dd curl minus=JH = curl

0 div =BH(H)B sdot= micro

E(E)J sdot= σ

A B curl= A B curl=

tdd- A E =

)dd( tAJ minus= σ

tdd curl curl AA σmicro minus=

AA) σωmicro iminus= curl )(curl(1

AA) σωmicro i=∆)((1

Eddy Current Tachometer

Construction of a speedometer (courtesy VDO Adolf Schinding AG) 1) spindle 2) bearing

3) holding spring 4) iron yoke 5) eddy current cup 6) shaft of the magnet 7) support of

the magnet 8) temperature compensation 9) permanent magnet 10) torsion spring

Proximity Sensors

Schematic diagram of a proximity sensor

Output current of a proximity switch versus distance

Inductive Flowmeters

)( Btimessdot= υqF

EqF sdot=BE times=υ

)(ds Btimes== υEU )(ds Btimes== υEU

)( Bd timessdot= υU

Bsdotsdotsdot= υdKU

Development of magnetic phase detection

sensor for steam generator tube

Dirac Son1 Kwan-Sang Ryu2 Duck-Gun Park3

1Hannam University Daejeon Rep of Korea2Korea Research Institute of Standards and Science Daejeon Rep of Korea3KoreaAtomic Energy Research Institute Daejeon Rep of Korea

Introduction

The layout of pressurized water reactor (PWR) components

Primary side Secondary side (non-radioactive side)(radioactive side)

The Structure of SG(Steam Generator)(degradation mechanism)

Secondary SidePrimary Side

SCC

A B

A-B

Steam outlet

Anti-vibration

SCC

Fretting

Wall thinning

IGA

U-bend

In commercial power plants SG- height up to 21 m - weight up to 800 tons - 2~4 sets of SG were installed - SG can contain from 3000 to

16000 tubes each about 20 mmin diameter

Primary coolant outlet Primary coolant inlet

Anti-vibrationbars

Tubesupportplate

Tubesheet

IGA

SCC

Pitting

SCC

Inside Tubesheet

Top of Tubesheet

by SSHwang of KAERI

Denting

Sludge pile

in diameter

The SGT is made of nickel basedInconel alloy which is composed of 75 Ni 165Cr and 815Fe

-Degradation mechanism corrosion pitting denting inter granular attack

-Inspection Eddy current Testing(ECT)

Permeability Variation Clusters (PVC)

(Ferro-magnetic phase)

-005

000

005

010

015

m (emug)

1-1

-002

000

002

004

006

008

m (emug)

1-2

-1000 -500 0 500 1000

-015

-010

-005

H ( Am )

-1000 -500 0 500 1000

-006

-004

-002

H ( Am )

The hystresis loop in the fragment of PVC parts of Kori-1 retired SG tube

-004

-002

000

002

004

006

M (emug)

Inconel 600 tested at RT

under tensile stress

1 2 3

4 5 6

7 8 9-004

-002

000

002

004

006

M(emug)

Inconel 600 Heat treated at

602 oC under tensile stress

1 2 3

How can we detect magnetic phase

(PVC)selectively from the flaws in SGT

-3000 -2000 -1000 0 1000 2000 3000

-006

H (Oe)

7 8 9

10 11 12

-3000 -2000 -1000 0 1000 2000 3000

-006

-004

H(Oe)

4 5 6

7 8 9

The hysteresis loop of the tensile tested specimen at room temperature (a) and tensile tested at high temperature (b)

The magnetic phase can be created under the high temperature andpressure conditions which is correspond to the stress corrosion crackingin the SG tube in the NPP(Bruemmer SM Charlot LA amp Henager CH (1988) Corrosion 782)

Principle of ECT

If we can separate magnetic phase selectively from the

flaws using magnetic sensor the reliability of EC in SGT

inspection will be greatly enhanced

Structure of the permeability

sensor

Dimension and photograph of U-shape

sensing yoke

Design of Magnetic Sensor for PVC

sensor sensing yoke

Photograph of the completed sensor front side (above) and rear side (bottom)

R11R12

R10

R8

R6

R9

R13

R7

R14

C18

1 n

C17

C20

C21

D2

DIODE

SIN COS

-

+

U-2A

4

13

2

-

+

U-2B

75

6

8

-

+

U-3A

13

2

8

+5VC19

104

+5V

Schematic diagram of the sensor system

Electronic Circuit of Magnetic Sensor

R20

R

R21

R

-

+

U5AD797

3

26

74

U6

D1

S12

GND3

+VCC4VCC5

IN6

-VCC7

S28

C41

R13

R26

R18

R25

R2210 Ω

R16

R14

R17

10 k

R15

R27

R32

R28

R33

R29

R34

5 k

R30

C29

C37

104

C32473

C39473C40

104

C33

104

C21

104C23

104

C25

104

C26

104

C30

104

C31

104

C35

104

C36

104

C27

104

C28

104

C34

104

C38

104

D3

DIODE

L1

1

2

L2

1

2

L3

1

2

4

-

+

U-4A

4

13

2

-

+

U-4B

75

6

8

-

+

U-5A

4

13

2

-

+

U-5B

75

6

8

-

+

U-6A

4

13

2

-

+

U-6B

75

6

8

C22

104

-5V

+5V

+5V

+5V

+5V

+5V

+5V

U7

D1

S12

GND3

+VCC4

VCC5

IN6

-VCC7

S28

+5V

-5V

-5V

-5V

-5V

-5V

-5V

-5V

-5V

R19

R24

R

R23

R

C24

OUT(X)

OUT(Y)

R1

20 kR210 k

R3

20 kR410 k

C1

104

C8

104

REF43

OUT(X)

OUT(Y)

REF43

U2

+Vcc1

CH02

CH13

CH24

CH35

COMM6

SHDN7

Vref8

+Vcc9

GND10

GND11

DOUT12BUSY13DIN14CS15

DIN16

-

+

U-1A

13

2

8

-

+

U-1B

4

75

6

C410 uF

C5104

DOUT

C210uF

C6104

C3104

DCLK

C7104

DIN

C10

01uF

CS

BUSY

C14 10uF

J1

CON6

123456

D1

DIODE

R5

47K

C9

10uF

C1310uF

Y1

OSC

OUT3

GND2

VCC4

U3

RSTVPP1

GND10

VCC20

XTAL15

XTAL24

P10AIN012P11AIN113P1214P1315P1416P1517P1618P1719

P30RXD2

P31TXD3

P32INT06

P33INT17

P34T08

P35T19

P3711

U4

C1+1

C1-3

C2+4

C2-5

VCC16

GND15

V+2

V-6

R1OUT12

R2OUT9

T1IN11

T2IN10

R1IN13

R2IN8

T1OUT14

T2OUT7

C12 10uF

C16

01uF

C15 10uF

C11

01uF

-5V

+5V

+5V

+5V

+5V

+5V

+5V

+5V

RST

OSC

OSC

RST

DCLKCSDINBUSYDOUT

U1

IN2

GND

4

OUT6

TEMP3

TRIM5

-5V

+5V

Electronic circuit diagram of the magnetic sensor

Photograph of the completed measuring system data acquisition

software in PC and probe scanning system

Experimental Setup for Magnetic Sensor

Reference material Scanning System Software LabVIEW

Reference Material (1) Normal defects and PVCs

Longitudinal and transverse defects

Def W L D Remarks

1 02 500 0213 (20 ) Inner defects

2 02 500 0427 (40 )

3 02 500 0213 (20 )Outer defectsPVC(1018)4 02 500 0427 (40 )

5 02 500 0639 (60 )

6 02 500 0852 (80 )

7 02 500 0639 (60 ) Inner defects

8 02 500 0852 (80 )

- 1 and 2 are inner defects

- 345 and 6 are outer defects with PVC

- 7 and 8 are inner defects

PVC

PVC

Defect Defect

For longitudinal defects and PVC For circumferential defects and PVC

ECT is very difficult to detect circumferential defects

We can distinguish PVCs and defects and longitudinal and circumferential defects

Flux-gate Magnetometer

One core sensor Two core sensor

3-축 flux-gate Magnetometer의 계략도

Sensorpia Co

pro

cess

or(

AV

R)

Sensor 1

RS422

Interface

Mic

ro-p

roce

ssor(

AV

R)

Sensor 2

Sensor 3

Interface

조립된 마그네토미터의 사진

Sensorpia Co

Analog PCB

Digital PCB

Sensorpia Co선형도(linearity)

10

20

30

40

50

60

y-axis

Magnetometer Output (microT)

-60 -50 -40 -30 -20 -10 0 10 20 30 40 50 60

-60

-50

-40

-30

-20

-10

0

10

Y-axis y=099946 x+0015STD 106E-4

Magnetometer Output (

Applied Magnetic Field (microT)

마그네토미터의 noise 특성 Sensorpia Co

1

10

100

y-axis

Magnetometer noise (nT)

0 1 2 3 4 5 6

1E-4

1E-3

001

01

Magnetometer noise (nT)

Frequency (Hz)

Magnetometer for KoDSAT

-150 -100 -50 0 50 100 150

-15

-10

-5

0

5

10

15

Magnetic Moment (Am

2)

Current (mA)

After Thermal Cycle Test

Measured

Resistance 193 ohm

Photograph of Magnetic torquer

Photograph of KoDSAT

Photograph of

3-axis Fluxgate

Magnetometer

Photograph of Magnetic torquer

Application of magnetometer

Moon magnetic fieldmeasurement

Telescope with direction indication

Joule Effect (Magnetostriction)

ϕ2cosel

l=

∆

0=∆

+∆

+∆

b

b

a

a

l

l

Actuator using Terfenol-D

00

05

10

B (T)

800

1000

1200

1400

1600

Magnetostriction (ppm)

-100 -50 0 50 100

-10

-05

00

B (T)

H (kAm)

2 MPa

4 MPa

6 MPa

8 MPa

10 MPa

12 MPa

-100 -50 0 50 100

-200

0

200

400

600

Magnetostriction (ppm)

H (kAm)

2 MPa

4 MPa

6 MPa

8 MPa

10 MPa

12 MPa

600

700

800

900

1000

-4 -3 -2 -1 0 1 2 3 4

0

10

20

30

40

50

60

Displacement (m

icro meter)

I (A)

FIELD

9 kAm

12 kAm

16 kAm

20 kAm

24 kAm

38 kAm

-50 -40 -30 -20 -10 0 10 20 30 40 50

-100

0

100

200

300

400

500

L (PPM)

H (kAm)

9 kAm

12 kAm

16 kAm

20 kAm

24 kAm

38 kAm

Magnetostrictive displacement sensor

Hysteresis loops under

tensile stress σ

(a) Crystalline 68 NiFe

λs = +25 10-6

(b) crystalline pure Ni λs

= -35 10-6

Villari Effect ( Inverse of Joule Effect)

= -35 10-6

(c) amorphous Co-based

alloy

λs = -35 10-6

ϕσλ 2sin2

3sdotsdot= smeE

γ

Permeability depending on the stress

σλmicromicro

1

3

2

Y

J

so

s

r =

γ

Calculated magnetization curves under stress

Variation of magnetization curve by an applied

tensile force (Co-based amorphous alloy)

Alloy Requirement

Materials for magnetoelastic sensors

Why amorphous magnetic materials are important

Stress-strain curves of several materials

Coercivity and hardness of several materials

Principles of magnetoelastic sensors

Non-contact torque sensor

Principle of cross torductor torque

sensor and flux pattern of sensor

poles on the surface of a shaft

a) without and b)with torsional load

Equivalent magnetic circuit of

cross type torque sensor

Helices of principal tensile and compressive stress on the surface of

a shaft subjected to torsion [32] Correlated changes of permeability

are detected by four-branch yoke system with sensing coils 123

and 4 and a common excitation pole

Examples of torque sensors

Four-branch type torque sensor

heads Pole structures realized

by commercial multi-pole

ferrites 14 and 18 min in

diameter (diameter of sensor

h e a d 1 7 a n d 2 4 m m

respectively) respectively)

Principle of Ring Torductor torque transducer

(a b) Physical structure (c) evolution of the

shaft surface under the transducer poles A and BRing torductor for measuring

torque on ship propeller shafts

(shaft diameter ca 500 mm)

(Courtesy ASEA Brown

Boveri AG)

Principal designs of coaxial torque sensors

Schematic diagram of data processing

electronics of a torque sensor

Extensometer (a) Construction of strain sensing element using

amorphous ribbon wound core (b) configuration of lumped

windings

∆E effect of an amorphous FeNi-based

alloy (Fe40 Ni38 Mo4 B18) Hs saturation

field

Magnetically tunable delay line

Torque Sensors using Amorphous wire

Sixtus tonk효과(large Barkhausen효과)

Hysteresis loops of a Wiegand wire for different reset fields

Curie 온도 및Hopkinson효과

Relation between normalised

saturation polarisation and

normalised Curie temperature

Permeability of a Mn-Zn ferrite as

a function of temperature and field

strength

Conclusions

1) Magnetic sensor 는 자동차 공장자동화 항공우주 및 군사용으로많이 사용되고 있다

2) 새로운 소재개발은 자기센서의 성능개발에 직접적인 영향을 준다2) 새로운 소재개발은 자기센서의 성능개발에 직접적인 영향을 준다

3) 센서의 개발을 위해서는 다양한 전공지식이 요구된다

(물리학 재료공학 기계공학 전자공학)

4) 센서분야가 고부가가치를 창출하는 부품사업이다

5) 핵심부품을 생산하는 중소기업의 item으로도 적절하다

What is Magnetoresistance

Magnetoresistance effect(AMR)

θθθ 2cos2

12sin12cos(

22 minusminus+∆asymp∆ xxxmx hhhRR

32 minusasymp∆ ρρ New effect GMR CMR and GMI

10 ge∆ ρρ

Two bridge configuration for

rotational angle measurement

measurement angle more than 180o

자동차 Engine Management System

Inductive and Eddy Current

Sensors Excited by Permanent Magnets

tNtU dd)( φsdotminus=

construction of an inductive

sensor (courtesy VDO Adolf sensor (courtesy VDO Adolf

Schindling AG)

1) constant socket

2) terminal package

3) permanent magnet

4) cap

5) soft magnetic core

6) coil

7) plate

8) blade connector

γγ

Sensor with yoke Change in the magnetic flux with

varying air gap Continuous lines

minimum air gap dashed lines

maximum air gap

C-shaped sensor

Sensor with radially

magnetized

permanent magnet

Signal Conditioning

Output voltage U of a DC-excited sensor with permanent

magnets when a single iron object passes by

Schematic electrical diagram of an inductive sensor

Linear Variable Differential Transformer

AC-Excited Sensors for Linear Movement

Principle of construction of an LVDT

Electrical circuit of an LVDT

tIMtNU dd dd sdotminus=sdotminus= φ

tIMtIMUUU dd dd 1212 sdotminussdot=minus=

tIMMU dd)( 12 sdotminus=

)(12 xMMMM =minus=

tIxMU dd)( sdot= tI

UxM

dd)( =

Signal Conditioning

power supply

carrier gen

autoampcontrol

LVDTcarrieramp

demod-ulator

phase

shifter

power supply

carrier gen

passivedemod-ulator

LVDTDCamp

Block diagram of a carrier amplifier system

Block diagram of a DC amplifier system

Variable Inductive Sensors

Principle of construction

of the VLP sensor

Principle of a bridge

circuit

lANL r 20 sdotsdotsdot= micromicro

21 BA UUU minus=

21)i(ii( 211 minus+sdot= LLLUU BA ωωω

)21))()((( minus∆minus+∆+∆+sdot= LLLLLLUU BA

)212)(( minus∆+sdot= LLLUU )212)(( minus∆+sdot= LLLUU BA

LLUU BA 21 ∆sdotsdot=

llLL ∆sdot=∆ d d

llLLUU BA ∆sdotsdot= d d)2(1

Applications and Properties

Principle of a construction of a force transducer

(courtesy Hottinger Baldwin Messtechnik)

Vibrationacceleration sensor

Signal Conditioning

Schematic electrical diagram of a force transducer connected with an

amplifier (courtesy Hottinger Baldwin Messtechnik GmbH)

Variable Gap Sensors

)( FeFe2

0 LLllANL micromicromicro +sdotsdot=

FeFe2

0max lANL sdotsdotsdot= micromicro

Construction of a variable gap sensor

Characteristic of a variable gap sensor

Construction of a differential

cross-anchor sensor

Output voltage U versus core

position x plusmn a limits of the

linear rage

Applications of differential cross-anchor sensors

AC-excited Sensors for Rotary Movements

Principle of construction of a synchro

α cos10 sdotsdot= UKU y

)120-( cos10 degsdotsdot= αUKU z

)240-( cos10 degsdotsdot= αUKU x

)120-( sin3100 degsdotsdotsdot=minus= αKUUUU yxyx

)240-( sin3100 degsdotsdotsdot=minus= αKUUUU zyzy

α sin3100 sdotsdotsdot=minus= KUUUU xzxz

Application to the Torque Sensor

Principle of construction of a torque-type synchro

Torque versus angular

difference

)( sin~ rt αα minussdotKM

)( cos~ rt1r αα minussdotUU

Principle of construction of a control-type sensor

Output voltage versus

angular difference

Principle of construction of a differential sychro

Eddy Current Sensors

tBE dd curl minus=JH = curl

0 div =BH(H)B sdot= micro

E(E)J sdot= σ

A B curl= A B curl=

tdd- A E =

)dd( tAJ minus= σ

tdd curl curl AA σmicro minus=

AA) σωmicro iminus= curl )(curl(1

AA) σωmicro i=∆)((1

Eddy Current Tachometer

Construction of a speedometer (courtesy VDO Adolf Schinding AG) 1) spindle 2) bearing

3) holding spring 4) iron yoke 5) eddy current cup 6) shaft of the magnet 7) support of

the magnet 8) temperature compensation 9) permanent magnet 10) torsion spring

Proximity Sensors

Schematic diagram of a proximity sensor

Output current of a proximity switch versus distance

Inductive Flowmeters

)( Btimessdot= υqF

EqF sdot=BE times=υ

)(ds Btimes== υEU )(ds Btimes== υEU

)( Bd timessdot= υU

Bsdotsdotsdot= υdKU

Development of magnetic phase detection

sensor for steam generator tube

Dirac Son1 Kwan-Sang Ryu2 Duck-Gun Park3

1Hannam University Daejeon Rep of Korea2Korea Research Institute of Standards and Science Daejeon Rep of Korea3KoreaAtomic Energy Research Institute Daejeon Rep of Korea

Introduction

The layout of pressurized water reactor (PWR) components

Primary side Secondary side (non-radioactive side)(radioactive side)

The Structure of SG(Steam Generator)(degradation mechanism)

Secondary SidePrimary Side

SCC

A B

A-B

Steam outlet

Anti-vibration

SCC

Fretting

Wall thinning

IGA

U-bend

In commercial power plants SG- height up to 21 m - weight up to 800 tons - 2~4 sets of SG were installed - SG can contain from 3000 to

16000 tubes each about 20 mmin diameter

Primary coolant outlet Primary coolant inlet

Anti-vibrationbars

Tubesupportplate

Tubesheet

IGA

SCC

Pitting

SCC

Inside Tubesheet

Top of Tubesheet

by SSHwang of KAERI

Denting

Sludge pile

in diameter

The SGT is made of nickel basedInconel alloy which is composed of 75 Ni 165Cr and 815Fe

-Degradation mechanism corrosion pitting denting inter granular attack

-Inspection Eddy current Testing(ECT)

Permeability Variation Clusters (PVC)

(Ferro-magnetic phase)

-005

000

005

010

015

m (emug)

1-1

-002

000

002

004

006

008

m (emug)

1-2

-1000 -500 0 500 1000

-015

-010

-005

H ( Am )

-1000 -500 0 500 1000

-006

-004

-002

H ( Am )

The hystresis loop in the fragment of PVC parts of Kori-1 retired SG tube

-004

-002

000

002

004

006

M (emug)

Inconel 600 tested at RT

under tensile stress

1 2 3

4 5 6

7 8 9-004

-002

000

002

004

006

M(emug)

Inconel 600 Heat treated at

602 oC under tensile stress

1 2 3

How can we detect magnetic phase

(PVC)selectively from the flaws in SGT

-3000 -2000 -1000 0 1000 2000 3000

-006

H (Oe)

7 8 9

10 11 12

-3000 -2000 -1000 0 1000 2000 3000

-006

-004

H(Oe)

4 5 6

7 8 9

The hysteresis loop of the tensile tested specimen at room temperature (a) and tensile tested at high temperature (b)

The magnetic phase can be created under the high temperature andpressure conditions which is correspond to the stress corrosion crackingin the SG tube in the NPP(Bruemmer SM Charlot LA amp Henager CH (1988) Corrosion 782)

Principle of ECT

If we can separate magnetic phase selectively from the

flaws using magnetic sensor the reliability of EC in SGT

inspection will be greatly enhanced

Structure of the permeability

sensor

Dimension and photograph of U-shape

sensing yoke

Design of Magnetic Sensor for PVC

sensor sensing yoke

Photograph of the completed sensor front side (above) and rear side (bottom)

R11R12

R10

R8

R6

R9

R13

R7

R14

C18

1 n

C17

C20

C21

D2

DIODE

SIN COS

-

+

U-2A

4

13

2

-

+

U-2B

75

6

8

-

+

U-3A

13

2

8

+5VC19

104

+5V

Schematic diagram of the sensor system

Electronic Circuit of Magnetic Sensor

R20

R

R21

R

-

+

U5AD797

3

26

74

U6

D1

S12

GND3

+VCC4VCC5

IN6

-VCC7

S28

C41

R13

R26

R18

R25

R2210 Ω

R16

R14

R17

10 k

R15

R27

R32

R28

R33

R29

R34

5 k

R30

C29

C37

104

C32473

C39473C40

104

C33

104

C21

104C23

104

C25

104

C26

104

C30

104

C31

104

C35

104

C36

104

C27

104

C28

104

C34

104

C38

104

D3

DIODE

L1

1

2

L2

1

2

L3

1

2

4

-

+

U-4A

4

13

2

-

+

U-4B

75

6

8

-

+

U-5A

4

13

2

-

+

U-5B

75

6

8

-

+

U-6A

4

13

2

-

+

U-6B

75

6

8

C22

104

-5V

+5V

+5V

+5V

+5V

+5V

+5V

U7

D1

S12

GND3

+VCC4

VCC5

IN6

-VCC7

S28

+5V

-5V

-5V

-5V

-5V

-5V

-5V

-5V

-5V

R19

R24

R

R23

R

C24

OUT(X)

OUT(Y)

R1

20 kR210 k

R3

20 kR410 k

C1

104

C8

104

REF43

OUT(X)

OUT(Y)

REF43

U2

+Vcc1

CH02

CH13

CH24

CH35

COMM6

SHDN7

Vref8

+Vcc9

GND10

GND11

DOUT12BUSY13DIN14CS15

DIN16

-

+

U-1A

13

2

8

-

+

U-1B

4

75

6

C410 uF

C5104

DOUT

C210uF

C6104

C3104

DCLK

C7104

DIN

C10

01uF

CS

BUSY

C14 10uF

J1

CON6

123456

D1

DIODE

R5

47K

C9

10uF

C1310uF

Y1

OSC

OUT3

GND2

VCC4

U3

RSTVPP1

GND10

VCC20

XTAL15

XTAL24

P10AIN012P11AIN113P1214P1315P1416P1517P1618P1719

P30RXD2

P31TXD3

P32INT06

P33INT17

P34T08

P35T19

P3711

U4

C1+1

C1-3

C2+4

C2-5

VCC16

GND15

V+2

V-6

R1OUT12

R2OUT9

T1IN11

T2IN10

R1IN13

R2IN8

T1OUT14

T2OUT7

C12 10uF

C16

01uF

C15 10uF

C11

01uF

-5V

+5V

+5V

+5V

+5V

+5V

+5V

+5V

RST

OSC

OSC

RST

DCLKCSDINBUSYDOUT

U1

IN2

GND

4

OUT6

TEMP3

TRIM5

-5V

+5V

Electronic circuit diagram of the magnetic sensor

Photograph of the completed measuring system data acquisition

software in PC and probe scanning system

Experimental Setup for Magnetic Sensor

Reference material Scanning System Software LabVIEW

Reference Material (1) Normal defects and PVCs

Longitudinal and transverse defects

Def W L D Remarks

1 02 500 0213 (20 ) Inner defects

2 02 500 0427 (40 )

3 02 500 0213 (20 )Outer defectsPVC(1018)4 02 500 0427 (40 )

5 02 500 0639 (60 )

6 02 500 0852 (80 )

7 02 500 0639 (60 ) Inner defects

8 02 500 0852 (80 )

- 1 and 2 are inner defects

- 345 and 6 are outer defects with PVC

- 7 and 8 are inner defects

PVC

PVC

Defect Defect

For longitudinal defects and PVC For circumferential defects and PVC

ECT is very difficult to detect circumferential defects

We can distinguish PVCs and defects and longitudinal and circumferential defects

Flux-gate Magnetometer

One core sensor Two core sensor

3-축 flux-gate Magnetometer의 계략도

Sensorpia Co

pro

cess

or(

AV

R)

Sensor 1

RS422

Interface

Mic

ro-p

roce

ssor(

AV

R)

Sensor 2

Sensor 3

Interface

조립된 마그네토미터의 사진

Sensorpia Co

Analog PCB

Digital PCB

Sensorpia Co선형도(linearity)

10

20

30

40

50

60

y-axis

Magnetometer Output (microT)

-60 -50 -40 -30 -20 -10 0 10 20 30 40 50 60

-60

-50

-40

-30

-20

-10

0

10

Y-axis y=099946 x+0015STD 106E-4

Magnetometer Output (

Applied Magnetic Field (microT)

마그네토미터의 noise 특성 Sensorpia Co

1

10

100

y-axis

Magnetometer noise (nT)

0 1 2 3 4 5 6

1E-4

1E-3

001

01

Magnetometer noise (nT)

Frequency (Hz)

Magnetometer for KoDSAT

-150 -100 -50 0 50 100 150

-15

-10

-5

0

5

10

15

Magnetic Moment (Am

2)

Current (mA)

After Thermal Cycle Test

Measured

Resistance 193 ohm

Photograph of Magnetic torquer

Photograph of KoDSAT

Photograph of

3-axis Fluxgate

Magnetometer

Photograph of Magnetic torquer

Application of magnetometer

Moon magnetic fieldmeasurement

Telescope with direction indication

Joule Effect (Magnetostriction)

ϕ2cosel

l=

∆

0=∆

+∆

+∆

b

b

a

a

l

l

Actuator using Terfenol-D

00

05

10

B (T)

800

1000

1200

1400

1600

Magnetostriction (ppm)

-100 -50 0 50 100

-10

-05

00

B (T)

H (kAm)

2 MPa

4 MPa

6 MPa

8 MPa

10 MPa

12 MPa

-100 -50 0 50 100

-200

0

200

400

600

Magnetostriction (ppm)

H (kAm)

2 MPa

4 MPa

6 MPa

8 MPa

10 MPa

12 MPa

600

700

800

900

1000

-4 -3 -2 -1 0 1 2 3 4

0

10

20

30

40

50

60

Displacement (m

icro meter)

I (A)

FIELD

9 kAm

12 kAm

16 kAm

20 kAm

24 kAm

38 kAm

-50 -40 -30 -20 -10 0 10 20 30 40 50

-100

0

100

200

300

400

500

L (PPM)

H (kAm)

9 kAm

12 kAm

16 kAm

20 kAm

24 kAm

38 kAm

Magnetostrictive displacement sensor

Hysteresis loops under

tensile stress σ

(a) Crystalline 68 NiFe

λs = +25 10-6

(b) crystalline pure Ni λs

= -35 10-6

Villari Effect ( Inverse of Joule Effect)

= -35 10-6

(c) amorphous Co-based

alloy

λs = -35 10-6

ϕσλ 2sin2

3sdotsdot= smeE

γ

Permeability depending on the stress

σλmicromicro

1

3

2

Y

J

so

s

r =

γ

Calculated magnetization curves under stress

Variation of magnetization curve by an applied

tensile force (Co-based amorphous alloy)

Alloy Requirement

Materials for magnetoelastic sensors

Why amorphous magnetic materials are important

Stress-strain curves of several materials

Coercivity and hardness of several materials

Principles of magnetoelastic sensors

Non-contact torque sensor

Principle of cross torductor torque

sensor and flux pattern of sensor

poles on the surface of a shaft

a) without and b)with torsional load

Equivalent magnetic circuit of

cross type torque sensor

Helices of principal tensile and compressive stress on the surface of

a shaft subjected to torsion [32] Correlated changes of permeability

are detected by four-branch yoke system with sensing coils 123

and 4 and a common excitation pole

Examples of torque sensors

Four-branch type torque sensor

heads Pole structures realized

by commercial multi-pole

ferrites 14 and 18 min in

diameter (diameter of sensor

h e a d 1 7 a n d 2 4 m m

respectively) respectively)

Principle of Ring Torductor torque transducer

(a b) Physical structure (c) evolution of the

shaft surface under the transducer poles A and BRing torductor for measuring

torque on ship propeller shafts

(shaft diameter ca 500 mm)

(Courtesy ASEA Brown

Boveri AG)

Principal designs of coaxial torque sensors

Schematic diagram of data processing

electronics of a torque sensor

Extensometer (a) Construction of strain sensing element using

amorphous ribbon wound core (b) configuration of lumped

windings

∆E effect of an amorphous FeNi-based

alloy (Fe40 Ni38 Mo4 B18) Hs saturation

field

Magnetically tunable delay line

Torque Sensors using Amorphous wire

Sixtus tonk효과(large Barkhausen효과)

Hysteresis loops of a Wiegand wire for different reset fields

Curie 온도 및Hopkinson효과

Relation between normalised

saturation polarisation and

normalised Curie temperature

Permeability of a Mn-Zn ferrite as

a function of temperature and field

strength

Conclusions

1) Magnetic sensor 는 자동차 공장자동화 항공우주 및 군사용으로많이 사용되고 있다

2) 새로운 소재개발은 자기센서의 성능개발에 직접적인 영향을 준다2) 새로운 소재개발은 자기센서의 성능개발에 직접적인 영향을 준다

3) 센서의 개발을 위해서는 다양한 전공지식이 요구된다

(물리학 재료공학 기계공학 전자공학)

4) 센서분야가 고부가가치를 창출하는 부품사업이다

5) 핵심부품을 생산하는 중소기업의 item으로도 적절하다

Two bridge configuration for

rotational angle measurement

measurement angle more than 180o

자동차 Engine Management System

Inductive and Eddy Current

Sensors Excited by Permanent Magnets

tNtU dd)( φsdotminus=

construction of an inductive

sensor (courtesy VDO Adolf sensor (courtesy VDO Adolf

Schindling AG)

1) constant socket

2) terminal package

3) permanent magnet

4) cap

5) soft magnetic core

6) coil

7) plate

8) blade connector

γγ

Sensor with yoke Change in the magnetic flux with

varying air gap Continuous lines

minimum air gap dashed lines

maximum air gap

C-shaped sensor

Sensor with radially

magnetized

permanent magnet

Signal Conditioning

Output voltage U of a DC-excited sensor with permanent

magnets when a single iron object passes by

Schematic electrical diagram of an inductive sensor

Linear Variable Differential Transformer

AC-Excited Sensors for Linear Movement

Principle of construction of an LVDT

Electrical circuit of an LVDT

tIMtNU dd dd sdotminus=sdotminus= φ

tIMtIMUUU dd dd 1212 sdotminussdot=minus=

tIMMU dd)( 12 sdotminus=

)(12 xMMMM =minus=

tIxMU dd)( sdot= tI

UxM

dd)( =

Signal Conditioning

power supply

carrier gen

autoampcontrol

LVDTcarrieramp

demod-ulator

phase

shifter

power supply

carrier gen

passivedemod-ulator

LVDTDCamp

Block diagram of a carrier amplifier system

Block diagram of a DC amplifier system

Variable Inductive Sensors

Principle of construction

of the VLP sensor

Principle of a bridge

circuit

lANL r 20 sdotsdotsdot= micromicro

21 BA UUU minus=

21)i(ii( 211 minus+sdot= LLLUU BA ωωω

)21))()((( minus∆minus+∆+∆+sdot= LLLLLLUU BA

)212)(( minus∆+sdot= LLLUU )212)(( minus∆+sdot= LLLUU BA

LLUU BA 21 ∆sdotsdot=

llLL ∆sdot=∆ d d

llLLUU BA ∆sdotsdot= d d)2(1

Applications and Properties

Principle of a construction of a force transducer

(courtesy Hottinger Baldwin Messtechnik)

Vibrationacceleration sensor

Signal Conditioning

Schematic electrical diagram of a force transducer connected with an

amplifier (courtesy Hottinger Baldwin Messtechnik GmbH)

Variable Gap Sensors

)( FeFe2

0 LLllANL micromicromicro +sdotsdot=

FeFe2

0max lANL sdotsdotsdot= micromicro

Construction of a variable gap sensor

Characteristic of a variable gap sensor

Construction of a differential

cross-anchor sensor

Output voltage U versus core

position x plusmn a limits of the

linear rage

Applications of differential cross-anchor sensors

AC-excited Sensors for Rotary Movements

Principle of construction of a synchro

α cos10 sdotsdot= UKU y

)120-( cos10 degsdotsdot= αUKU z

)240-( cos10 degsdotsdot= αUKU x

)120-( sin3100 degsdotsdotsdot=minus= αKUUUU yxyx

)240-( sin3100 degsdotsdotsdot=minus= αKUUUU zyzy

α sin3100 sdotsdotsdot=minus= KUUUU xzxz

Application to the Torque Sensor

Principle of construction of a torque-type synchro

Torque versus angular

difference

)( sin~ rt αα minussdotKM

)( cos~ rt1r αα minussdotUU

Principle of construction of a control-type sensor

Output voltage versus

angular difference

Principle of construction of a differential sychro

Eddy Current Sensors

tBE dd curl minus=JH = curl

0 div =BH(H)B sdot= micro

E(E)J sdot= σ

A B curl= A B curl=

tdd- A E =

)dd( tAJ minus= σ

tdd curl curl AA σmicro minus=

AA) σωmicro iminus= curl )(curl(1

AA) σωmicro i=∆)((1

Eddy Current Tachometer

Construction of a speedometer (courtesy VDO Adolf Schinding AG) 1) spindle 2) bearing

3) holding spring 4) iron yoke 5) eddy current cup 6) shaft of the magnet 7) support of

the magnet 8) temperature compensation 9) permanent magnet 10) torsion spring

Proximity Sensors

Schematic diagram of a proximity sensor

Output current of a proximity switch versus distance

Inductive Flowmeters

)( Btimessdot= υqF

EqF sdot=BE times=υ

)(ds Btimes== υEU )(ds Btimes== υEU

)( Bd timessdot= υU

Bsdotsdotsdot= υdKU

Development of magnetic phase detection

sensor for steam generator tube

Dirac Son1 Kwan-Sang Ryu2 Duck-Gun Park3

1Hannam University Daejeon Rep of Korea2Korea Research Institute of Standards and Science Daejeon Rep of Korea3KoreaAtomic Energy Research Institute Daejeon Rep of Korea

Introduction

The layout of pressurized water reactor (PWR) components

Primary side Secondary side (non-radioactive side)(radioactive side)

The Structure of SG(Steam Generator)(degradation mechanism)

Secondary SidePrimary Side

SCC

A B

A-B

Steam outlet

Anti-vibration

SCC

Fretting

Wall thinning

IGA

U-bend

In commercial power plants SG- height up to 21 m - weight up to 800 tons - 2~4 sets of SG were installed - SG can contain from 3000 to

16000 tubes each about 20 mmin diameter

Primary coolant outlet Primary coolant inlet

Anti-vibrationbars

Tubesupportplate

Tubesheet

IGA

SCC

Pitting

SCC

Inside Tubesheet

Top of Tubesheet

by SSHwang of KAERI

Denting

Sludge pile

in diameter

The SGT is made of nickel basedInconel alloy which is composed of 75 Ni 165Cr and 815Fe

-Degradation mechanism corrosion pitting denting inter granular attack

-Inspection Eddy current Testing(ECT)

Permeability Variation Clusters (PVC)

(Ferro-magnetic phase)

-005

000

005

010

015

m (emug)

1-1

-002

000

002

004

006

008

m (emug)

1-2

-1000 -500 0 500 1000

-015

-010

-005

H ( Am )

-1000 -500 0 500 1000

-006

-004

-002

H ( Am )

The hystresis loop in the fragment of PVC parts of Kori-1 retired SG tube

-004

-002

000

002

004

006

M (emug)

Inconel 600 tested at RT

under tensile stress

1 2 3

4 5 6

7 8 9-004

-002

000

002

004

006

M(emug)

Inconel 600 Heat treated at

602 oC under tensile stress

1 2 3

How can we detect magnetic phase

(PVC)selectively from the flaws in SGT

-3000 -2000 -1000 0 1000 2000 3000

-006

H (Oe)

7 8 9

10 11 12

-3000 -2000 -1000 0 1000 2000 3000

-006

-004

H(Oe)

4 5 6

7 8 9

The hysteresis loop of the tensile tested specimen at room temperature (a) and tensile tested at high temperature (b)

The magnetic phase can be created under the high temperature andpressure conditions which is correspond to the stress corrosion crackingin the SG tube in the NPP(Bruemmer SM Charlot LA amp Henager CH (1988) Corrosion 782)

Principle of ECT

If we can separate magnetic phase selectively from the

flaws using magnetic sensor the reliability of EC in SGT

inspection will be greatly enhanced

Structure of the permeability

sensor

Dimension and photograph of U-shape

sensing yoke

Design of Magnetic Sensor for PVC

sensor sensing yoke

Photograph of the completed sensor front side (above) and rear side (bottom)

R11R12

R10

R8

R6

R9

R13

R7

R14

C18

1 n

C17

C20

C21

D2

DIODE

SIN COS

-

+

U-2A

4

13

2

-

+

U-2B

75

6

8

-

+

U-3A

13

2

8

+5VC19

104

+5V

Schematic diagram of the sensor system

Electronic Circuit of Magnetic Sensor

R20

R

R21

R

-

+

U5AD797

3

26

74

U6

D1

S12

GND3

+VCC4VCC5

IN6

-VCC7

S28

C41

R13

R26

R18

R25

R2210 Ω

R16

R14

R17

10 k

R15

R27

R32

R28

R33

R29

R34

5 k

R30

C29

C37

104

C32473

C39473C40

104

C33

104

C21

104C23

104

C25

104

C26

104

C30

104

C31

104

C35

104

C36

104

C27

104

C28

104

C34

104

C38

104

D3

DIODE

L1

1

2

L2

1

2

L3

1

2

4

-

+

U-4A

4

13

2

-

+

U-4B

75

6

8

-

+

U-5A

4

13

2

-

+

U-5B

75

6

8

-

+

U-6A

4

13

2

-

+

U-6B

75

6

8

C22

104

-5V

+5V

+5V

+5V

+5V

+5V

+5V

U7

D1

S12

GND3

+VCC4

VCC5

IN6

-VCC7

S28

+5V

-5V

-5V

-5V

-5V

-5V

-5V

-5V

-5V

R19

R24

R

R23

R

C24

OUT(X)

OUT(Y)

R1

20 kR210 k

R3

20 kR410 k

C1

104

C8

104

REF43

OUT(X)

OUT(Y)

REF43

U2

+Vcc1

CH02

CH13

CH24

CH35

COMM6

SHDN7

Vref8

+Vcc9

GND10

GND11

DOUT12BUSY13DIN14CS15

DIN16

-

+

U-1A

13

2

8

-

+

U-1B

4

75

6

C410 uF

C5104

DOUT

C210uF

C6104

C3104

DCLK

C7104

DIN

C10

01uF

CS

BUSY

C14 10uF

J1

CON6

123456

D1

DIODE

R5

47K

C9

10uF

C1310uF

Y1

OSC

OUT3

GND2

VCC4

U3

RSTVPP1

GND10

VCC20

XTAL15

XTAL24

P10AIN012P11AIN113P1214P1315P1416P1517P1618P1719

P30RXD2

P31TXD3

P32INT06

P33INT17

P34T08

P35T19

P3711

U4

C1+1

C1-3

C2+4

C2-5

VCC16

GND15

V+2

V-6

R1OUT12

R2OUT9

T1IN11

T2IN10

R1IN13

R2IN8

T1OUT14

T2OUT7

C12 10uF

C16

01uF

C15 10uF

C11

01uF

-5V

+5V

+5V

+5V

+5V

+5V

+5V

+5V

RST

OSC

OSC

RST

DCLKCSDINBUSYDOUT

U1

IN2

GND

4

OUT6

TEMP3

TRIM5

-5V

+5V

Electronic circuit diagram of the magnetic sensor

Photograph of the completed measuring system data acquisition

software in PC and probe scanning system

Experimental Setup for Magnetic Sensor

Reference material Scanning System Software LabVIEW

Reference Material (1) Normal defects and PVCs

Longitudinal and transverse defects

Def W L D Remarks

1 02 500 0213 (20 ) Inner defects

2 02 500 0427 (40 )

3 02 500 0213 (20 )Outer defectsPVC(1018)4 02 500 0427 (40 )

5 02 500 0639 (60 )

6 02 500 0852 (80 )

7 02 500 0639 (60 ) Inner defects

8 02 500 0852 (80 )

- 1 and 2 are inner defects

- 345 and 6 are outer defects with PVC

- 7 and 8 are inner defects

PVC

PVC

Defect Defect

For longitudinal defects and PVC For circumferential defects and PVC

ECT is very difficult to detect circumferential defects

We can distinguish PVCs and defects and longitudinal and circumferential defects

Flux-gate Magnetometer

One core sensor Two core sensor

3-축 flux-gate Magnetometer의 계략도

Sensorpia Co

pro

cess

or(

AV

R)

Sensor 1

RS422

Interface

Mic

ro-p

roce

ssor(

AV

R)

Sensor 2

Sensor 3

Interface

조립된 마그네토미터의 사진

Sensorpia Co

Analog PCB

Digital PCB

Sensorpia Co선형도(linearity)

10

20

30

40

50

60

y-axis

Magnetometer Output (microT)

-60 -50 -40 -30 -20 -10 0 10 20 30 40 50 60

-60

-50

-40

-30

-20

-10

0

10

Y-axis y=099946 x+0015STD 106E-4

Magnetometer Output (

Applied Magnetic Field (microT)

마그네토미터의 noise 특성 Sensorpia Co

1

10

100

y-axis

Magnetometer noise (nT)

0 1 2 3 4 5 6

1E-4

1E-3

001

01

Magnetometer noise (nT)

Frequency (Hz)

Magnetometer for KoDSAT

-150 -100 -50 0 50 100 150

-15

-10

-5

0

5

10

15

Magnetic Moment (Am

2)

Current (mA)

After Thermal Cycle Test

Measured

Resistance 193 ohm

Photograph of Magnetic torquer

Photograph of KoDSAT

Photograph of

3-axis Fluxgate

Magnetometer

Photograph of Magnetic torquer

Application of magnetometer

Moon magnetic fieldmeasurement

Telescope with direction indication

Joule Effect (Magnetostriction)

ϕ2cosel

l=

∆

0=∆

+∆

+∆

b

b

a

a

l

l

Actuator using Terfenol-D

00

05

10

B (T)

800

1000

1200

1400

1600

Magnetostriction (ppm)

-100 -50 0 50 100

-10

-05

00

B (T)

H (kAm)

2 MPa

4 MPa

6 MPa

8 MPa

10 MPa

12 MPa

-100 -50 0 50 100

-200

0

200

400

600

Magnetostriction (ppm)

H (kAm)

2 MPa

4 MPa

6 MPa

8 MPa

10 MPa

12 MPa

600

700

800

900

1000

-4 -3 -2 -1 0 1 2 3 4

0

10

20

30

40

50

60

Displacement (m

icro meter)

I (A)

FIELD

9 kAm

12 kAm

16 kAm

20 kAm

24 kAm

38 kAm

-50 -40 -30 -20 -10 0 10 20 30 40 50

-100

0

100

200

300

400

500

L (PPM)

H (kAm)

9 kAm

12 kAm

16 kAm

20 kAm

24 kAm

38 kAm

Magnetostrictive displacement sensor

Hysteresis loops under

tensile stress σ

(a) Crystalline 68 NiFe

λs = +25 10-6

(b) crystalline pure Ni λs

= -35 10-6

Villari Effect ( Inverse of Joule Effect)

= -35 10-6

(c) amorphous Co-based

alloy

λs = -35 10-6

ϕσλ 2sin2

3sdotsdot= smeE

γ

Permeability depending on the stress

σλmicromicro

1

3

2

Y

J

so

s

r =

γ

Calculated magnetization curves under stress

Variation of magnetization curve by an applied

tensile force (Co-based amorphous alloy)

Alloy Requirement

Materials for magnetoelastic sensors

Why amorphous magnetic materials are important

Stress-strain curves of several materials

Coercivity and hardness of several materials

Principles of magnetoelastic sensors

Non-contact torque sensor

Principle of cross torductor torque

sensor and flux pattern of sensor

poles on the surface of a shaft

a) without and b)with torsional load

Equivalent magnetic circuit of

cross type torque sensor

Helices of principal tensile and compressive stress on the surface of

a shaft subjected to torsion [32] Correlated changes of permeability

are detected by four-branch yoke system with sensing coils 123

and 4 and a common excitation pole

Examples of torque sensors

Four-branch type torque sensor

heads Pole structures realized

by commercial multi-pole

ferrites 14 and 18 min in

diameter (diameter of sensor

h e a d 1 7 a n d 2 4 m m

respectively) respectively)

Principle of Ring Torductor torque transducer

(a b) Physical structure (c) evolution of the

shaft surface under the transducer poles A and BRing torductor for measuring

torque on ship propeller shafts

(shaft diameter ca 500 mm)

(Courtesy ASEA Brown

Boveri AG)

Principal designs of coaxial torque sensors

Schematic diagram of data processing

electronics of a torque sensor

Extensometer (a) Construction of strain sensing element using

amorphous ribbon wound core (b) configuration of lumped

windings

∆E effect of an amorphous FeNi-based

alloy (Fe40 Ni38 Mo4 B18) Hs saturation

field

Magnetically tunable delay line

Torque Sensors using Amorphous wire

Sixtus tonk효과(large Barkhausen효과)

Hysteresis loops of a Wiegand wire for different reset fields

Curie 온도 및Hopkinson효과

Relation between normalised

saturation polarisation and

normalised Curie temperature

Permeability of a Mn-Zn ferrite as

a function of temperature and field

strength

Conclusions

1) Magnetic sensor 는 자동차 공장자동화 항공우주 및 군사용으로많이 사용되고 있다

2) 새로운 소재개발은 자기센서의 성능개발에 직접적인 영향을 준다2) 새로운 소재개발은 자기센서의 성능개발에 직접적인 영향을 준다

3) 센서의 개발을 위해서는 다양한 전공지식이 요구된다

(물리학 재료공학 기계공학 전자공학)

4) 센서분야가 고부가가치를 창출하는 부품사업이다

5) 핵심부품을 생산하는 중소기업의 item으로도 적절하다

measurement angle more than 180o

자동차 Engine Management System

Inductive and Eddy Current

Sensors Excited by Permanent Magnets

tNtU dd)( φsdotminus=

construction of an inductive

sensor (courtesy VDO Adolf sensor (courtesy VDO Adolf

Schindling AG)

1) constant socket

2) terminal package

3) permanent magnet

4) cap

5) soft magnetic core

6) coil

7) plate

8) blade connector

γγ

Sensor with yoke Change in the magnetic flux with

varying air gap Continuous lines

minimum air gap dashed lines

maximum air gap

C-shaped sensor

Sensor with radially

magnetized

permanent magnet

Signal Conditioning

Output voltage U of a DC-excited sensor with permanent

magnets when a single iron object passes by

Schematic electrical diagram of an inductive sensor

Linear Variable Differential Transformer

AC-Excited Sensors for Linear Movement

Principle of construction of an LVDT

Electrical circuit of an LVDT

tIMtNU dd dd sdotminus=sdotminus= φ

tIMtIMUUU dd dd 1212 sdotminussdot=minus=

tIMMU dd)( 12 sdotminus=

)(12 xMMMM =minus=

tIxMU dd)( sdot= tI

UxM

dd)( =

Signal Conditioning

power supply

carrier gen

autoampcontrol

LVDTcarrieramp

demod-ulator

phase

shifter

power supply

carrier gen

passivedemod-ulator

LVDTDCamp

Block diagram of a carrier amplifier system

Block diagram of a DC amplifier system

Variable Inductive Sensors

Principle of construction

of the VLP sensor

Principle of a bridge

circuit

lANL r 20 sdotsdotsdot= micromicro

21 BA UUU minus=

21)i(ii( 211 minus+sdot= LLLUU BA ωωω

)21))()((( minus∆minus+∆+∆+sdot= LLLLLLUU BA

)212)(( minus∆+sdot= LLLUU )212)(( minus∆+sdot= LLLUU BA

LLUU BA 21 ∆sdotsdot=

llLL ∆sdot=∆ d d

llLLUU BA ∆sdotsdot= d d)2(1

Applications and Properties

Principle of a construction of a force transducer

(courtesy Hottinger Baldwin Messtechnik)

Vibrationacceleration sensor

Signal Conditioning

Schematic electrical diagram of a force transducer connected with an

amplifier (courtesy Hottinger Baldwin Messtechnik GmbH)

Variable Gap Sensors

)( FeFe2

0 LLllANL micromicromicro +sdotsdot=

FeFe2

0max lANL sdotsdotsdot= micromicro

Construction of a variable gap sensor

Characteristic of a variable gap sensor

Construction of a differential

cross-anchor sensor

Output voltage U versus core

position x plusmn a limits of the

linear rage

Applications of differential cross-anchor sensors

AC-excited Sensors for Rotary Movements

Principle of construction of a synchro

α cos10 sdotsdot= UKU y

)120-( cos10 degsdotsdot= αUKU z

)240-( cos10 degsdotsdot= αUKU x

)120-( sin3100 degsdotsdotsdot=minus= αKUUUU yxyx

)240-( sin3100 degsdotsdotsdot=minus= αKUUUU zyzy

α sin3100 sdotsdotsdot=minus= KUUUU xzxz

Application to the Torque Sensor

Principle of construction of a torque-type synchro

Torque versus angular

difference

)( sin~ rt αα minussdotKM

)( cos~ rt1r αα minussdotUU

Principle of construction of a control-type sensor

Output voltage versus

angular difference

Principle of construction of a differential sychro

Eddy Current Sensors

tBE dd curl minus=JH = curl

0 div =BH(H)B sdot= micro

E(E)J sdot= σ

A B curl= A B curl=

tdd- A E =

)dd( tAJ minus= σ

tdd curl curl AA σmicro minus=

AA) σωmicro iminus= curl )(curl(1

AA) σωmicro i=∆)((1

Eddy Current Tachometer

Construction of a speedometer (courtesy VDO Adolf Schinding AG) 1) spindle 2) bearing

3) holding spring 4) iron yoke 5) eddy current cup 6) shaft of the magnet 7) support of

the magnet 8) temperature compensation 9) permanent magnet 10) torsion spring

Proximity Sensors

Schematic diagram of a proximity sensor

Output current of a proximity switch versus distance

Inductive Flowmeters

)( Btimessdot= υqF

EqF sdot=BE times=υ

)(ds Btimes== υEU )(ds Btimes== υEU

)( Bd timessdot= υU

Bsdotsdotsdot= υdKU

Development of magnetic phase detection

sensor for steam generator tube

Dirac Son1 Kwan-Sang Ryu2 Duck-Gun Park3

1Hannam University Daejeon Rep of Korea2Korea Research Institute of Standards and Science Daejeon Rep of Korea3KoreaAtomic Energy Research Institute Daejeon Rep of Korea

Introduction

The layout of pressurized water reactor (PWR) components

Primary side Secondary side (non-radioactive side)(radioactive side)

The Structure of SG(Steam Generator)(degradation mechanism)

Secondary SidePrimary Side

SCC

A B

A-B

Steam outlet

Anti-vibration

SCC

Fretting

Wall thinning

IGA

U-bend

In commercial power plants SG- height up to 21 m - weight up to 800 tons - 2~4 sets of SG were installed - SG can contain from 3000 to

16000 tubes each about 20 mmin diameter

Primary coolant outlet Primary coolant inlet

Anti-vibrationbars

Tubesupportplate

Tubesheet

IGA

SCC

Pitting

SCC

Inside Tubesheet

Top of Tubesheet

by SSHwang of KAERI

Denting

Sludge pile

in diameter

The SGT is made of nickel basedInconel alloy which is composed of 75 Ni 165Cr and 815Fe

-Degradation mechanism corrosion pitting denting inter granular attack

-Inspection Eddy current Testing(ECT)

Permeability Variation Clusters (PVC)

(Ferro-magnetic phase)

-005

000

005

010

015

m (emug)

1-1

-002

000

002

004

006

008

m (emug)

1-2

-1000 -500 0 500 1000

-015

-010

-005

H ( Am )

-1000 -500 0 500 1000

-006

-004

-002

H ( Am )

The hystresis loop in the fragment of PVC parts of Kori-1 retired SG tube

-004

-002

000

002

004

006

M (emug)

Inconel 600 tested at RT

under tensile stress

1 2 3

4 5 6

7 8 9-004

-002

000

002

004

006

M(emug)

Inconel 600 Heat treated at

602 oC under tensile stress

1 2 3

How can we detect magnetic phase

(PVC)selectively from the flaws in SGT

-3000 -2000 -1000 0 1000 2000 3000

-006

H (Oe)

7 8 9

10 11 12

-3000 -2000 -1000 0 1000 2000 3000

-006

-004

H(Oe)

4 5 6

7 8 9

The hysteresis loop of the tensile tested specimen at room temperature (a) and tensile tested at high temperature (b)

The magnetic phase can be created under the high temperature andpressure conditions which is correspond to the stress corrosion crackingin the SG tube in the NPP(Bruemmer SM Charlot LA amp Henager CH (1988) Corrosion 782)

Principle of ECT

If we can separate magnetic phase selectively from the

flaws using magnetic sensor the reliability of EC in SGT

inspection will be greatly enhanced

Structure of the permeability

sensor

Dimension and photograph of U-shape

sensing yoke

Design of Magnetic Sensor for PVC

sensor sensing yoke

Photograph of the completed sensor front side (above) and rear side (bottom)

R11R12

R10

R8

R6

R9

R13

R7

R14

C18

1 n

C17

C20

C21

D2

DIODE

SIN COS

-

+

U-2A

4

13

2

-

+

U-2B

75

6

8

-

+

U-3A

13

2

8

+5VC19

104

+5V

Schematic diagram of the sensor system

Electronic Circuit of Magnetic Sensor

R20

R

R21

R

-

+

U5AD797

3

26

74

U6

D1

S12

GND3

+VCC4VCC5

IN6

-VCC7

S28

C41

R13

R26

R18

R25

R2210 Ω

R16

R14

R17

10 k

R15

R27

R32

R28

R33

R29

R34

5 k

R30

C29

C37

104

C32473

C39473C40

104

C33

104

C21

104C23

104

C25

104

C26

104

C30

104

C31

104

C35

104

C36

104

C27

104

C28

104

C34

104

C38

104

D3

DIODE

L1

1

2

L2

1

2

L3

1

2

4

-

+

U-4A

4

13

2

-

+

U-4B

75

6

8

-

+

U-5A

4

13

2

-

+

U-5B

75

6

8

-

+

U-6A

4

13

2

-

+

U-6B

75

6

8

C22

104

-5V

+5V

+5V

+5V

+5V

+5V

+5V

U7

D1

S12

GND3

+VCC4

VCC5

IN6

-VCC7

S28

+5V

-5V

-5V

-5V

-5V

-5V

-5V

-5V

-5V

R19

R24

R

R23

R

C24

OUT(X)

OUT(Y)

R1

20 kR210 k

R3

20 kR410 k

C1

104

C8

104

REF43

OUT(X)

OUT(Y)

REF43

U2

+Vcc1

CH02

CH13

CH24

CH35

COMM6

SHDN7

Vref8

+Vcc9

GND10

GND11

DOUT12BUSY13DIN14CS15

DIN16

-

+

U-1A

13

2

8

-

+

U-1B

4

75

6

C410 uF

C5104

DOUT

C210uF

C6104

C3104

DCLK

C7104

DIN

C10

01uF

CS

BUSY

C14 10uF

J1

CON6

123456

D1

DIODE

R5

47K

C9

10uF

C1310uF

Y1

OSC

OUT3

GND2

VCC4

U3

RSTVPP1

GND10

VCC20

XTAL15

XTAL24

P10AIN012P11AIN113P1214P1315P1416P1517P1618P1719

P30RXD2

P31TXD3

P32INT06

P33INT17

P34T08

P35T19

P3711

U4

C1+1

C1-3

C2+4

C2-5

VCC16

GND15

V+2

V-6

R1OUT12

R2OUT9

T1IN11

T2IN10

R1IN13

R2IN8

T1OUT14

T2OUT7

C12 10uF

C16

01uF

C15 10uF

C11

01uF

-5V

+5V

+5V

+5V

+5V

+5V

+5V

+5V

RST

OSC

OSC

RST

DCLKCSDINBUSYDOUT

U1

IN2

GND

4

OUT6

TEMP3

TRIM5

-5V

+5V

Electronic circuit diagram of the magnetic sensor

Photograph of the completed measuring system data acquisition

software in PC and probe scanning system

Experimental Setup for Magnetic Sensor

Reference material Scanning System Software LabVIEW

Reference Material (1) Normal defects and PVCs

Longitudinal and transverse defects

Def W L D Remarks

1 02 500 0213 (20 ) Inner defects

2 02 500 0427 (40 )

3 02 500 0213 (20 )Outer defectsPVC(1018)4 02 500 0427 (40 )

5 02 500 0639 (60 )

6 02 500 0852 (80 )

7 02 500 0639 (60 ) Inner defects

8 02 500 0852 (80 )

- 1 and 2 are inner defects

- 345 and 6 are outer defects with PVC

- 7 and 8 are inner defects

PVC

PVC

Defect Defect

For longitudinal defects and PVC For circumferential defects and PVC

ECT is very difficult to detect circumferential defects

We can distinguish PVCs and defects and longitudinal and circumferential defects

Flux-gate Magnetometer

One core sensor Two core sensor

3-축 flux-gate Magnetometer의 계략도

Sensorpia Co

pro

cess

or(

AV

R)

Sensor 1

RS422

Interface

Mic

ro-p

roce

ssor(

AV

R)

Sensor 2

Sensor 3

Interface

조립된 마그네토미터의 사진

Sensorpia Co

Analog PCB

Digital PCB

Sensorpia Co선형도(linearity)

10

20

30

40

50

60

y-axis

Magnetometer Output (microT)

-60 -50 -40 -30 -20 -10 0 10 20 30 40 50 60

-60

-50

-40

-30

-20

-10

0

10

Y-axis y=099946 x+0015STD 106E-4

Magnetometer Output (

Applied Magnetic Field (microT)

마그네토미터의 noise 특성 Sensorpia Co

1

10

100

y-axis

Magnetometer noise (nT)

0 1 2 3 4 5 6

1E-4

1E-3

001

01

Magnetometer noise (nT)

Frequency (Hz)

Magnetometer for KoDSAT

-150 -100 -50 0 50 100 150

-15

-10

-5

0

5

10

15

Magnetic Moment (Am

2)

Current (mA)

After Thermal Cycle Test

Measured

Resistance 193 ohm

Photograph of Magnetic torquer

Photograph of KoDSAT

Photograph of

3-axis Fluxgate

Magnetometer

Photograph of Magnetic torquer

Application of magnetometer

Moon magnetic fieldmeasurement

Telescope with direction indication

Joule Effect (Magnetostriction)

ϕ2cosel

l=

∆

0=∆

+∆

+∆

b

b

a

a

l

l

Actuator using Terfenol-D

00

05

10

B (T)

800

1000

1200

1400

1600

Magnetostriction (ppm)

-100 -50 0 50 100

-10

-05

00

B (T)

H (kAm)

2 MPa

4 MPa

6 MPa

8 MPa

10 MPa

12 MPa

-100 -50 0 50 100

-200

0

200

400

600

Magnetostriction (ppm)

H (kAm)

2 MPa

4 MPa

6 MPa

8 MPa

10 MPa

12 MPa

600

700

800

900

1000

-4 -3 -2 -1 0 1 2 3 4

0

10

20

30

40

50

60

Displacement (m

icro meter)

I (A)

FIELD

9 kAm

12 kAm

16 kAm

20 kAm

24 kAm

38 kAm

-50 -40 -30 -20 -10 0 10 20 30 40 50

-100

0

100

200

300

400

500

L (PPM)

H (kAm)

9 kAm

12 kAm

16 kAm

20 kAm

24 kAm

38 kAm

Magnetostrictive displacement sensor

Hysteresis loops under

tensile stress σ

(a) Crystalline 68 NiFe

λs = +25 10-6

(b) crystalline pure Ni λs

= -35 10-6

Villari Effect ( Inverse of Joule Effect)

= -35 10-6

(c) amorphous Co-based

alloy

λs = -35 10-6

ϕσλ 2sin2

3sdotsdot= smeE

γ

Permeability depending on the stress

σλmicromicro

1

3

2

Y

J

so

s

r =

γ

Calculated magnetization curves under stress

Variation of magnetization curve by an applied

tensile force (Co-based amorphous alloy)

Alloy Requirement

Materials for magnetoelastic sensors

Why amorphous magnetic materials are important

Stress-strain curves of several materials

Coercivity and hardness of several materials

Principles of magnetoelastic sensors

Non-contact torque sensor

Principle of cross torductor torque

sensor and flux pattern of sensor

poles on the surface of a shaft

a) without and b)with torsional load

Equivalent magnetic circuit of

cross type torque sensor

Helices of principal tensile and compressive stress on the surface of

a shaft subjected to torsion [32] Correlated changes of permeability

are detected by four-branch yoke system with sensing coils 123

and 4 and a common excitation pole

Examples of torque sensors

Four-branch type torque sensor

heads Pole structures realized

by commercial multi-pole

ferrites 14 and 18 min in

diameter (diameter of sensor

h e a d 1 7 a n d 2 4 m m

respectively) respectively)

Principle of Ring Torductor torque transducer

(a b) Physical structure (c) evolution of the

shaft surface under the transducer poles A and BRing torductor for measuring

torque on ship propeller shafts

(shaft diameter ca 500 mm)

(Courtesy ASEA Brown

Boveri AG)

Principal designs of coaxial torque sensors

Schematic diagram of data processing

electronics of a torque sensor

Extensometer (a) Construction of strain sensing element using

amorphous ribbon wound core (b) configuration of lumped

windings

∆E effect of an amorphous FeNi-based

alloy (Fe40 Ni38 Mo4 B18) Hs saturation

field

Magnetically tunable delay line

Torque Sensors using Amorphous wire

Sixtus tonk효과(large Barkhausen효과)

Hysteresis loops of a Wiegand wire for different reset fields

Curie 온도 및Hopkinson효과

Relation between normalised

saturation polarisation and

normalised Curie temperature

Permeability of a Mn-Zn ferrite as

a function of temperature and field

strength

Conclusions

1) Magnetic sensor 는 자동차 공장자동화 항공우주 및 군사용으로많이 사용되고 있다

2) 새로운 소재개발은 자기센서의 성능개발에 직접적인 영향을 준다2) 새로운 소재개발은 자기센서의 성능개발에 직접적인 영향을 준다

3) 센서의 개발을 위해서는 다양한 전공지식이 요구된다

(물리학 재료공학 기계공학 전자공학)

4) 센서분야가 고부가가치를 창출하는 부품사업이다

5) 핵심부품을 생산하는 중소기업의 item으로도 적절하다

자동차 Engine Management System

Inductive and Eddy Current

Sensors Excited by Permanent Magnets

tNtU dd)( φsdotminus=

construction of an inductive

sensor (courtesy VDO Adolf sensor (courtesy VDO Adolf

Schindling AG)

1) constant socket

2) terminal package

3) permanent magnet

4) cap

5) soft magnetic core

6) coil

7) plate

8) blade connector

γγ

Sensor with yoke Change in the magnetic flux with

varying air gap Continuous lines

minimum air gap dashed lines

maximum air gap

C-shaped sensor

Sensor with radially

magnetized

permanent magnet

Signal Conditioning

Output voltage U of a DC-excited sensor with permanent

magnets when a single iron object passes by

Schematic electrical diagram of an inductive sensor

Linear Variable Differential Transformer

AC-Excited Sensors for Linear Movement

Principle of construction of an LVDT

Electrical circuit of an LVDT

tIMtNU dd dd sdotminus=sdotminus= φ

tIMtIMUUU dd dd 1212 sdotminussdot=minus=

tIMMU dd)( 12 sdotminus=

)(12 xMMMM =minus=

tIxMU dd)( sdot= tI

UxM

dd)( =

Signal Conditioning

power supply

carrier gen

autoampcontrol

LVDTcarrieramp

demod-ulator

phase

shifter

power supply

carrier gen

passivedemod-ulator

LVDTDCamp

Block diagram of a carrier amplifier system

Block diagram of a DC amplifier system

Variable Inductive Sensors

Principle of construction

of the VLP sensor

Principle of a bridge

circuit

lANL r 20 sdotsdotsdot= micromicro

21 BA UUU minus=

21)i(ii( 211 minus+sdot= LLLUU BA ωωω

)21))()((( minus∆minus+∆+∆+sdot= LLLLLLUU BA

)212)(( minus∆+sdot= LLLUU )212)(( minus∆+sdot= LLLUU BA

LLUU BA 21 ∆sdotsdot=

llLL ∆sdot=∆ d d

llLLUU BA ∆sdotsdot= d d)2(1

Applications and Properties

Principle of a construction of a force transducer

(courtesy Hottinger Baldwin Messtechnik)

Vibrationacceleration sensor

Signal Conditioning

Schematic electrical diagram of a force transducer connected with an

amplifier (courtesy Hottinger Baldwin Messtechnik GmbH)

Variable Gap Sensors

)( FeFe2

0 LLllANL micromicromicro +sdotsdot=

FeFe2

0max lANL sdotsdotsdot= micromicro

Construction of a variable gap sensor

Characteristic of a variable gap sensor

Construction of a differential

cross-anchor sensor

Output voltage U versus core

position x plusmn a limits of the

linear rage

Applications of differential cross-anchor sensors

AC-excited Sensors for Rotary Movements

Principle of construction of a synchro

α cos10 sdotsdot= UKU y

)120-( cos10 degsdotsdot= αUKU z

)240-( cos10 degsdotsdot= αUKU x

)120-( sin3100 degsdotsdotsdot=minus= αKUUUU yxyx

)240-( sin3100 degsdotsdotsdot=minus= αKUUUU zyzy

α sin3100 sdotsdotsdot=minus= KUUUU xzxz

Application to the Torque Sensor

Principle of construction of a torque-type synchro

Torque versus angular

difference

)( sin~ rt αα minussdotKM

)( cos~ rt1r αα minussdotUU

Principle of construction of a control-type sensor

Output voltage versus

angular difference

Principle of construction of a differential sychro

Eddy Current Sensors

tBE dd curl minus=JH = curl

0 div =BH(H)B sdot= micro

E(E)J sdot= σ

A B curl= A B curl=

tdd- A E =

)dd( tAJ minus= σ

tdd curl curl AA σmicro minus=

AA) σωmicro iminus= curl )(curl(1

AA) σωmicro i=∆)((1

Eddy Current Tachometer

Construction of a speedometer (courtesy VDO Adolf Schinding AG) 1) spindle 2) bearing

3) holding spring 4) iron yoke 5) eddy current cup 6) shaft of the magnet 7) support of

the magnet 8) temperature compensation 9) permanent magnet 10) torsion spring

Proximity Sensors

Schematic diagram of a proximity sensor

Output current of a proximity switch versus distance

Inductive Flowmeters

)( Btimessdot= υqF

EqF sdot=BE times=υ

)(ds Btimes== υEU )(ds Btimes== υEU

)( Bd timessdot= υU

Bsdotsdotsdot= υdKU

Development of magnetic phase detection

sensor for steam generator tube

Dirac Son1 Kwan-Sang Ryu2 Duck-Gun Park3

1Hannam University Daejeon Rep of Korea2Korea Research Institute of Standards and Science Daejeon Rep of Korea3KoreaAtomic Energy Research Institute Daejeon Rep of Korea

Introduction

The layout of pressurized water reactor (PWR) components

Primary side Secondary side (non-radioactive side)(radioactive side)

The Structure of SG(Steam Generator)(degradation mechanism)

Secondary SidePrimary Side

SCC

A B

A-B

Steam outlet

Anti-vibration

SCC

Fretting

Wall thinning

IGA

U-bend

In commercial power plants SG- height up to 21 m - weight up to 800 tons - 2~4 sets of SG were installed - SG can contain from 3000 to

16000 tubes each about 20 mmin diameter

Primary coolant outlet Primary coolant inlet

Anti-vibrationbars

Tubesupportplate

Tubesheet

IGA

SCC

Pitting

SCC

Inside Tubesheet

Top of Tubesheet

by SSHwang of KAERI

Denting

Sludge pile

in diameter

The SGT is made of nickel basedInconel alloy which is composed of 75 Ni 165Cr and 815Fe

-Degradation mechanism corrosion pitting denting inter granular attack

-Inspection Eddy current Testing(ECT)

Permeability Variation Clusters (PVC)

(Ferro-magnetic phase)

-005

000

005

010

015

m (emug)

1-1

-002

000

002

004

006

008

m (emug)

1-2

-1000 -500 0 500 1000

-015

-010

-005

H ( Am )

-1000 -500 0 500 1000

-006

-004

-002

H ( Am )

The hystresis loop in the fragment of PVC parts of Kori-1 retired SG tube

-004

-002

000

002

004

006

M (emug)

Inconel 600 tested at RT

under tensile stress

1 2 3

4 5 6

7 8 9-004

-002

000

002

004

006

M(emug)

Inconel 600 Heat treated at

602 oC under tensile stress

1 2 3

How can we detect magnetic phase

(PVC)selectively from the flaws in SGT

-3000 -2000 -1000 0 1000 2000 3000

-006

H (Oe)

7 8 9

10 11 12

-3000 -2000 -1000 0 1000 2000 3000

-006

-004

H(Oe)

4 5 6

7 8 9

The hysteresis loop of the tensile tested specimen at room temperature (a) and tensile tested at high temperature (b)

The magnetic phase can be created under the high temperature andpressure conditions which is correspond to the stress corrosion crackingin the SG tube in the NPP(Bruemmer SM Charlot LA amp Henager CH (1988) Corrosion 782)

Principle of ECT

If we can separate magnetic phase selectively from the

flaws using magnetic sensor the reliability of EC in SGT

inspection will be greatly enhanced

Structure of the permeability

sensor

Dimension and photograph of U-shape

sensing yoke

Design of Magnetic Sensor for PVC

sensor sensing yoke

Photograph of the completed sensor front side (above) and rear side (bottom)

R11R12

R10

R8

R6

R9

R13

R7

R14

C18

1 n

C17

C20

C21

D2

DIODE

SIN COS

-

+

U-2A

4

13

2

-

+

U-2B

75

6

8

-

+

U-3A

13

2

8

+5VC19

104

+5V

Schematic diagram of the sensor system

Electronic Circuit of Magnetic Sensor

R20

R

R21

R

-

+

U5AD797

3

26

74

U6

D1

S12

GND3

+VCC4VCC5

IN6

-VCC7

S28

C41

R13

R26

R18

R25

R2210 Ω

R16

R14

R17

10 k

R15

R27

R32

R28

R33

R29

R34

5 k

R30

C29

C37

104

C32473

C39473C40

104

C33

104

C21

104C23

104

C25

104

C26

104

C30

104

C31

104

C35

104

C36

104

C27

104

C28

104

C34

104

C38

104

D3

DIODE

L1

1

2

L2

1

2

L3

1

2

4

-

+

U-4A

4

13

2

-

+

U-4B

75

6

8

-

+

U-5A

4

13

2

-

+

U-5B

75

6

8

-

+

U-6A

4

13

2

-

+

U-6B

75

6

8

C22

104

-5V

+5V

+5V

+5V

+5V

+5V

+5V

U7

D1

S12

GND3

+VCC4

VCC5

IN6

-VCC7

S28

+5V

-5V

-5V

-5V

-5V

-5V

-5V

-5V

-5V

R19

R24

R

R23

R

C24

OUT(X)

OUT(Y)

R1

20 kR210 k

R3

20 kR410 k

C1

104

C8

104

REF43

OUT(X)

OUT(Y)

REF43

U2

+Vcc1

CH02

CH13

CH24

CH35

COMM6

SHDN7

Vref8

+Vcc9

GND10

GND11

DOUT12BUSY13DIN14CS15

DIN16

-

+

U-1A

13

2

8

-

+

U-1B

4

75

6

C410 uF

C5104

DOUT

C210uF

C6104

C3104

DCLK

C7104

DIN

C10

01uF

CS

BUSY

C14 10uF

J1

CON6

123456

D1

DIODE

R5

47K

C9

10uF

C1310uF

Y1

OSC

OUT3

GND2

VCC4

U3

RSTVPP1

GND10

VCC20

XTAL15

XTAL24

P10AIN012P11AIN113P1214P1315P1416P1517P1618P1719

P30RXD2

P31TXD3

P32INT06

P33INT17

P34T08

P35T19

P3711

U4

C1+1

C1-3

C2+4

C2-5

VCC16

GND15

V+2

V-6

R1OUT12

R2OUT9

T1IN11

T2IN10

R1IN13

R2IN8

T1OUT14

T2OUT7

C12 10uF

C16

01uF

C15 10uF

C11

01uF

-5V

+5V

+5V

+5V

+5V

+5V

+5V

+5V

RST

OSC

OSC

RST

DCLKCSDINBUSYDOUT

U1

IN2

GND

4

OUT6

TEMP3

TRIM5

-5V

+5V

Electronic circuit diagram of the magnetic sensor

Photograph of the completed measuring system data acquisition

software in PC and probe scanning system

Experimental Setup for Magnetic Sensor

Reference material Scanning System Software LabVIEW

Reference Material (1) Normal defects and PVCs

Longitudinal and transverse defects

Def W L D Remarks

1 02 500 0213 (20 ) Inner defects

2 02 500 0427 (40 )

3 02 500 0213 (20 )Outer defectsPVC(1018)4 02 500 0427 (40 )

5 02 500 0639 (60 )

6 02 500 0852 (80 )

7 02 500 0639 (60 ) Inner defects

8 02 500 0852 (80 )

- 1 and 2 are inner defects

- 345 and 6 are outer defects with PVC

- 7 and 8 are inner defects

PVC

PVC

Defect Defect

For longitudinal defects and PVC For circumferential defects and PVC

ECT is very difficult to detect circumferential defects

We can distinguish PVCs and defects and longitudinal and circumferential defects

Flux-gate Magnetometer

One core sensor Two core sensor

3-축 flux-gate Magnetometer의 계략도

Sensorpia Co

pro

cess

or(

AV

R)

Sensor 1

RS422

Interface

Mic

ro-p

roce

ssor(

AV

R)

Sensor 2

Sensor 3

Interface

조립된 마그네토미터의 사진

Sensorpia Co

Analog PCB

Digital PCB

Sensorpia Co선형도(linearity)

10

20

30

40

50

60

y-axis

Magnetometer Output (microT)

-60 -50 -40 -30 -20 -10 0 10 20 30 40 50 60

-60

-50

-40

-30

-20

-10

0

10

Y-axis y=099946 x+0015STD 106E-4

Magnetometer Output (

Applied Magnetic Field (microT)

마그네토미터의 noise 특성 Sensorpia Co

1

10

100

y-axis

Magnetometer noise (nT)

0 1 2 3 4 5 6

1E-4

1E-3

001

01

Magnetometer noise (nT)

Frequency (Hz)

Magnetometer for KoDSAT

-150 -100 -50 0 50 100 150

-15

-10

-5

0

5

10

15

Magnetic Moment (Am

2)

Current (mA)

After Thermal Cycle Test

Measured

Resistance 193 ohm

Photograph of Magnetic torquer

Photograph of KoDSAT

Photograph of

3-axis Fluxgate

Magnetometer

Photograph of Magnetic torquer

Application of magnetometer

Moon magnetic fieldmeasurement

Telescope with direction indication

Joule Effect (Magnetostriction)

ϕ2cosel

l=

∆

0=∆

+∆

+∆

b

b

a

a

l

l

Actuator using Terfenol-D

00

05

10

B (T)

800

1000

1200

1400

1600

Magnetostriction (ppm)

-100 -50 0 50 100

-10

-05

00

B (T)

H (kAm)

2 MPa

4 MPa

6 MPa

8 MPa

10 MPa

12 MPa

-100 -50 0 50 100

-200

0

200

400

600

Magnetostriction (ppm)

H (kAm)

2 MPa

4 MPa

6 MPa

8 MPa

10 MPa

12 MPa

600

700

800

900

1000

-4 -3 -2 -1 0 1 2 3 4

0

10

20

30

40

50

60

Displacement (m

icro meter)

I (A)

FIELD

9 kAm

12 kAm

16 kAm

20 kAm

24 kAm

38 kAm

-50 -40 -30 -20 -10 0 10 20 30 40 50

-100

0

100

200

300

400

500

L (PPM)

H (kAm)

9 kAm

12 kAm

16 kAm

20 kAm

24 kAm

38 kAm

Magnetostrictive displacement sensor

Hysteresis loops under

tensile stress σ

(a) Crystalline 68 NiFe

λs = +25 10-6

(b) crystalline pure Ni λs

= -35 10-6

Villari Effect ( Inverse of Joule Effect)

= -35 10-6

(c) amorphous Co-based

alloy

λs = -35 10-6

ϕσλ 2sin2

3sdotsdot= smeE

γ

Permeability depending on the stress

σλmicromicro

1

3

2

Y

J

so

s

r =

γ

Calculated magnetization curves under stress

Variation of magnetization curve by an applied

tensile force (Co-based amorphous alloy)

Alloy Requirement

Materials for magnetoelastic sensors

Why amorphous magnetic materials are important

Stress-strain curves of several materials

Coercivity and hardness of several materials

Principles of magnetoelastic sensors

Non-contact torque sensor

Principle of cross torductor torque

sensor and flux pattern of sensor

poles on the surface of a shaft

a) without and b)with torsional load

Equivalent magnetic circuit of

cross type torque sensor

Helices of principal tensile and compressive stress on the surface of

a shaft subjected to torsion [32] Correlated changes of permeability

are detected by four-branch yoke system with sensing coils 123

and 4 and a common excitation pole

Examples of torque sensors

Four-branch type torque sensor

heads Pole structures realized

by commercial multi-pole

ferrites 14 and 18 min in

diameter (diameter of sensor

h e a d 1 7 a n d 2 4 m m

respectively) respectively)

Principle of Ring Torductor torque transducer

(a b) Physical structure (c) evolution of the

shaft surface under the transducer poles A and BRing torductor for measuring

torque on ship propeller shafts

(shaft diameter ca 500 mm)

(Courtesy ASEA Brown

Boveri AG)

Principal designs of coaxial torque sensors

Schematic diagram of data processing

electronics of a torque sensor

Extensometer (a) Construction of strain sensing element using

amorphous ribbon wound core (b) configuration of lumped

windings

∆E effect of an amorphous FeNi-based

alloy (Fe40 Ni38 Mo4 B18) Hs saturation

field

Magnetically tunable delay line

Torque Sensors using Amorphous wire

Sixtus tonk효과(large Barkhausen효과)

Hysteresis loops of a Wiegand wire for different reset fields

Curie 온도 및Hopkinson효과

Relation between normalised

saturation polarisation and

normalised Curie temperature

Permeability of a Mn-Zn ferrite as

a function of temperature and field

strength

Conclusions

1) Magnetic sensor 는 자동차 공장자동화 항공우주 및 군사용으로많이 사용되고 있다

2) 새로운 소재개발은 자기센서의 성능개발에 직접적인 영향을 준다2) 새로운 소재개발은 자기센서의 성능개발에 직접적인 영향을 준다

3) 센서의 개발을 위해서는 다양한 전공지식이 요구된다

(물리학 재료공학 기계공학 전자공학)

4) 센서분야가 고부가가치를 창출하는 부품사업이다

5) 핵심부품을 생산하는 중소기업의 item으로도 적절하다

Inductive and Eddy Current

Sensors Excited by Permanent Magnets

tNtU dd)( φsdotminus=

construction of an inductive

sensor (courtesy VDO Adolf sensor (courtesy VDO Adolf

Schindling AG)

1) constant socket

2) terminal package

3) permanent magnet

4) cap

5) soft magnetic core

6) coil

7) plate

8) blade connector

γγ

Sensor with yoke Change in the magnetic flux with

varying air gap Continuous lines

minimum air gap dashed lines

maximum air gap

C-shaped sensor

Sensor with radially

magnetized

permanent magnet

Signal Conditioning

Output voltage U of a DC-excited sensor with permanent

magnets when a single iron object passes by

Schematic electrical diagram of an inductive sensor

Linear Variable Differential Transformer

AC-Excited Sensors for Linear Movement

Principle of construction of an LVDT

Electrical circuit of an LVDT

tIMtNU dd dd sdotminus=sdotminus= φ

tIMtIMUUU dd dd 1212 sdotminussdot=minus=

tIMMU dd)( 12 sdotminus=

)(12 xMMMM =minus=

tIxMU dd)( sdot= tI

UxM

dd)( =

Signal Conditioning

power supply

carrier gen

autoampcontrol

LVDTcarrieramp

demod-ulator

phase

shifter

power supply

carrier gen

passivedemod-ulator

LVDTDCamp

Block diagram of a carrier amplifier system

Block diagram of a DC amplifier system

Variable Inductive Sensors

Principle of construction

of the VLP sensor

Principle of a bridge

circuit

lANL r 20 sdotsdotsdot= micromicro

21 BA UUU minus=

21)i(ii( 211 minus+sdot= LLLUU BA ωωω

)21))()((( minus∆minus+∆+∆+sdot= LLLLLLUU BA

)212)(( minus∆+sdot= LLLUU )212)(( minus∆+sdot= LLLUU BA

LLUU BA 21 ∆sdotsdot=

llLL ∆sdot=∆ d d

llLLUU BA ∆sdotsdot= d d)2(1

Applications and Properties

Principle of a construction of a force transducer

(courtesy Hottinger Baldwin Messtechnik)

Vibrationacceleration sensor

Signal Conditioning

Schematic electrical diagram of a force transducer connected with an

amplifier (courtesy Hottinger Baldwin Messtechnik GmbH)

Variable Gap Sensors

)( FeFe2

0 LLllANL micromicromicro +sdotsdot=

FeFe2

0max lANL sdotsdotsdot= micromicro

Construction of a variable gap sensor

Characteristic of a variable gap sensor

Construction of a differential

cross-anchor sensor

Output voltage U versus core

position x plusmn a limits of the

linear rage

Applications of differential cross-anchor sensors

AC-excited Sensors for Rotary Movements

Principle of construction of a synchro

α cos10 sdotsdot= UKU y

)120-( cos10 degsdotsdot= αUKU z

)240-( cos10 degsdotsdot= αUKU x

)120-( sin3100 degsdotsdotsdot=minus= αKUUUU yxyx

)240-( sin3100 degsdotsdotsdot=minus= αKUUUU zyzy

α sin3100 sdotsdotsdot=minus= KUUUU xzxz

Application to the Torque Sensor

Principle of construction of a torque-type synchro

Torque versus angular

difference

)( sin~ rt αα minussdotKM

)( cos~ rt1r αα minussdotUU

Principle of construction of a control-type sensor

Output voltage versus

angular difference

Principle of construction of a differential sychro

Eddy Current Sensors

tBE dd curl minus=JH = curl

0 div =BH(H)B sdot= micro

E(E)J sdot= σ

A B curl= A B curl=

tdd- A E =

)dd( tAJ minus= σ

tdd curl curl AA σmicro minus=

AA) σωmicro iminus= curl )(curl(1

AA) σωmicro i=∆)((1

Eddy Current Tachometer

Construction of a speedometer (courtesy VDO Adolf Schinding AG) 1) spindle 2) bearing

3) holding spring 4) iron yoke 5) eddy current cup 6) shaft of the magnet 7) support of

the magnet 8) temperature compensation 9) permanent magnet 10) torsion spring

Proximity Sensors

Schematic diagram of a proximity sensor

Output current of a proximity switch versus distance

Inductive Flowmeters

)( Btimessdot= υqF

EqF sdot=BE times=υ

)(ds Btimes== υEU )(ds Btimes== υEU

)( Bd timessdot= υU

Bsdotsdotsdot= υdKU

Development of magnetic phase detection

sensor for steam generator tube

Dirac Son1 Kwan-Sang Ryu2 Duck-Gun Park3

1Hannam University Daejeon Rep of Korea2Korea Research Institute of Standards and Science Daejeon Rep of Korea3KoreaAtomic Energy Research Institute Daejeon Rep of Korea

Introduction

The layout of pressurized water reactor (PWR) components

Primary side Secondary side (non-radioactive side)(radioactive side)

The Structure of SG(Steam Generator)(degradation mechanism)

Secondary SidePrimary Side

SCC

A B

A-B

Steam outlet

Anti-vibration

SCC

Fretting

Wall thinning

IGA

U-bend

In commercial power plants SG- height up to 21 m - weight up to 800 tons - 2~4 sets of SG were installed - SG can contain from 3000 to

16000 tubes each about 20 mmin diameter

Primary coolant outlet Primary coolant inlet

Anti-vibrationbars

Tubesupportplate

Tubesheet

IGA

SCC

Pitting

SCC

Inside Tubesheet

Top of Tubesheet

by SSHwang of KAERI

Denting

Sludge pile

in diameter

The SGT is made of nickel basedInconel alloy which is composed of 75 Ni 165Cr and 815Fe

-Degradation mechanism corrosion pitting denting inter granular attack

-Inspection Eddy current Testing(ECT)

Permeability Variation Clusters (PVC)

(Ferro-magnetic phase)

-005

000

005

010

015

m (emug)

1-1

-002

000

002

004

006

008

m (emug)

1-2

-1000 -500 0 500 1000

-015

-010

-005

H ( Am )

-1000 -500 0 500 1000

-006

-004

-002

H ( Am )

The hystresis loop in the fragment of PVC parts of Kori-1 retired SG tube

-004

-002

000

002

004

006

M (emug)

Inconel 600 tested at RT

under tensile stress

1 2 3

4 5 6

7 8 9-004

-002

000

002

004

006

M(emug)

Inconel 600 Heat treated at

602 oC under tensile stress

1 2 3

How can we detect magnetic phase

(PVC)selectively from the flaws in SGT

-3000 -2000 -1000 0 1000 2000 3000

-006

H (Oe)

7 8 9

10 11 12

-3000 -2000 -1000 0 1000 2000 3000

-006

-004

H(Oe)

4 5 6

7 8 9

The hysteresis loop of the tensile tested specimen at room temperature (a) and tensile tested at high temperature (b)

The magnetic phase can be created under the high temperature andpressure conditions which is correspond to the stress corrosion crackingin the SG tube in the NPP(Bruemmer SM Charlot LA amp Henager CH (1988) Corrosion 782)

Principle of ECT

If we can separate magnetic phase selectively from the

flaws using magnetic sensor the reliability of EC in SGT

inspection will be greatly enhanced

Structure of the permeability

sensor

Dimension and photograph of U-shape

sensing yoke

Design of Magnetic Sensor for PVC

sensor sensing yoke

Photograph of the completed sensor front side (above) and rear side (bottom)

R11R12

R10

R8

R6

R9

R13

R7

R14

C18

1 n

C17

C20

C21

D2

DIODE

SIN COS

-

+

U-2A

4

13

2

-

+

U-2B

75

6

8

-

+

U-3A

13

2

8

+5VC19

104

+5V

Schematic diagram of the sensor system

Electronic Circuit of Magnetic Sensor

R20

R

R21

R

-

+

U5AD797

3

26

74

U6

D1

S12

GND3

+VCC4VCC5

IN6

-VCC7

S28

C41

R13

R26

R18

R25

R2210 Ω

R16

R14

R17

10 k

R15

R27

R32

R28

R33

R29

R34

5 k

R30

C29

C37

104

C32473

C39473C40

104

C33

104

C21

104C23

104

C25

104

C26

104

C30

104

C31

104

C35

104

C36

104

C27

104

C28

104

C34

104

C38

104

D3

DIODE

L1

1

2

L2

1

2

L3

1

2

4

-

+

U-4A

4

13

2

-

+

U-4B

75

6

8

-

+

U-5A

4

13

2

-

+

U-5B

75

6

8

-

+

U-6A

4

13

2

-

+

U-6B

75

6

8

C22

104

-5V

+5V

+5V

+5V

+5V

+5V

+5V

U7

D1

S12

GND3

+VCC4

VCC5

IN6

-VCC7

S28

+5V

-5V

-5V

-5V

-5V

-5V

-5V

-5V

-5V

R19

R24

R

R23

R

C24

OUT(X)

OUT(Y)

R1

20 kR210 k

R3

20 kR410 k

C1

104

C8

104

REF43

OUT(X)

OUT(Y)

REF43

U2

+Vcc1

CH02

CH13

CH24

CH35

COMM6

SHDN7

Vref8

+Vcc9

GND10

GND11

DOUT12BUSY13DIN14CS15

DIN16

-

+

U-1A

13

2

8

-

+

U-1B

4

75

6

C410 uF

C5104

DOUT

C210uF

C6104

C3104

DCLK

C7104

DIN

C10

01uF

CS

BUSY

C14 10uF

J1

CON6

123456

D1

DIODE

R5

47K

C9

10uF

C1310uF

Y1

OSC

OUT3

GND2

VCC4

U3

RSTVPP1

GND10

VCC20

XTAL15

XTAL24

P10AIN012P11AIN113P1214P1315P1416P1517P1618P1719

P30RXD2

P31TXD3

P32INT06

P33INT17

P34T08

P35T19

P3711

U4

C1+1

C1-3

C2+4

C2-5

VCC16

GND15

V+2

V-6

R1OUT12

R2OUT9

T1IN11

T2IN10

R1IN13

R2IN8

T1OUT14

T2OUT7

C12 10uF

C16

01uF

C15 10uF

C11

01uF

-5V

+5V

+5V

+5V

+5V

+5V

+5V

+5V

RST

OSC

OSC

RST

DCLKCSDINBUSYDOUT

U1

IN2

GND

4

OUT6

TEMP3

TRIM5

-5V

+5V

Electronic circuit diagram of the magnetic sensor

Photograph of the completed measuring system data acquisition

software in PC and probe scanning system

Experimental Setup for Magnetic Sensor

Reference material Scanning System Software LabVIEW

Reference Material (1) Normal defects and PVCs

Longitudinal and transverse defects

Def W L D Remarks

1 02 500 0213 (20 ) Inner defects

2 02 500 0427 (40 )

3 02 500 0213 (20 )Outer defectsPVC(1018)4 02 500 0427 (40 )

5 02 500 0639 (60 )

6 02 500 0852 (80 )

7 02 500 0639 (60 ) Inner defects

8 02 500 0852 (80 )

- 1 and 2 are inner defects

- 345 and 6 are outer defects with PVC

- 7 and 8 are inner defects

PVC

PVC

Defect Defect

For longitudinal defects and PVC For circumferential defects and PVC

ECT is very difficult to detect circumferential defects

We can distinguish PVCs and defects and longitudinal and circumferential defects

Flux-gate Magnetometer

One core sensor Two core sensor

3-축 flux-gate Magnetometer의 계략도

Sensorpia Co

pro

cess

or(

AV

R)

Sensor 1

RS422

Interface

Mic

ro-p

roce

ssor(

AV

R)

Sensor 2

Sensor 3

Interface

조립된 마그네토미터의 사진

Sensorpia Co

Analog PCB

Digital PCB

Sensorpia Co선형도(linearity)

10

20

30

40

50

60

y-axis

Magnetometer Output (microT)

-60 -50 -40 -30 -20 -10 0 10 20 30 40 50 60

-60

-50

-40

-30

-20

-10

0

10

Y-axis y=099946 x+0015STD 106E-4

Magnetometer Output (

Applied Magnetic Field (microT)

마그네토미터의 noise 특성 Sensorpia Co

1

10

100

y-axis

Magnetometer noise (nT)

0 1 2 3 4 5 6

1E-4

1E-3

001

01

Magnetometer noise (nT)

Frequency (Hz)

Magnetometer for KoDSAT

-150 -100 -50 0 50 100 150

-15

-10

-5

0

5

10

15

Magnetic Moment (Am

2)

Current (mA)

After Thermal Cycle Test

Measured

Resistance 193 ohm

Photograph of Magnetic torquer

Photograph of KoDSAT

Photograph of

3-axis Fluxgate

Magnetometer

Photograph of Magnetic torquer

Application of magnetometer

Moon magnetic fieldmeasurement

Telescope with direction indication

Joule Effect (Magnetostriction)

ϕ2cosel

l=

∆

0=∆

+∆

+∆

b

b

a

a

l

l

Actuator using Terfenol-D

00

05

10

B (T)

800

1000

1200

1400

1600

Magnetostriction (ppm)

-100 -50 0 50 100

-10

-05

00

B (T)

H (kAm)

2 MPa

4 MPa

6 MPa

8 MPa

10 MPa

12 MPa

-100 -50 0 50 100

-200

0

200

400

600

Magnetostriction (ppm)

H (kAm)

2 MPa

4 MPa

6 MPa

8 MPa

10 MPa

12 MPa

600

700

800

900

1000

-4 -3 -2 -1 0 1 2 3 4

0

10

20

30

40

50

60

Displacement (m

icro meter)

I (A)

FIELD

9 kAm

12 kAm

16 kAm

20 kAm

24 kAm

38 kAm

-50 -40 -30 -20 -10 0 10 20 30 40 50

-100

0

100

200

300

400

500

L (PPM)

H (kAm)

9 kAm

12 kAm

16 kAm

20 kAm

24 kAm

38 kAm

Magnetostrictive displacement sensor

Hysteresis loops under

tensile stress σ

(a) Crystalline 68 NiFe

λs = +25 10-6

(b) crystalline pure Ni λs

= -35 10-6

Villari Effect ( Inverse of Joule Effect)

= -35 10-6

(c) amorphous Co-based

alloy

λs = -35 10-6

ϕσλ 2sin2

3sdotsdot= smeE

γ

Permeability depending on the stress

σλmicromicro

1

3

2

Y

J

so

s

r =

γ

Calculated magnetization curves under stress

Variation of magnetization curve by an applied

tensile force (Co-based amorphous alloy)

Alloy Requirement

Materials for magnetoelastic sensors

Why amorphous magnetic materials are important

Stress-strain curves of several materials

Coercivity and hardness of several materials

Principles of magnetoelastic sensors

Non-contact torque sensor

Principle of cross torductor torque

sensor and flux pattern of sensor

poles on the surface of a shaft

a) without and b)with torsional load

Equivalent magnetic circuit of

cross type torque sensor

Helices of principal tensile and compressive stress on the surface of

a shaft subjected to torsion [32] Correlated changes of permeability

are detected by four-branch yoke system with sensing coils 123

and 4 and a common excitation pole

Examples of torque sensors

Four-branch type torque sensor

heads Pole structures realized

by commercial multi-pole

ferrites 14 and 18 min in

diameter (diameter of sensor

h e a d 1 7 a n d 2 4 m m

respectively) respectively)

Principle of Ring Torductor torque transducer

(a b) Physical structure (c) evolution of the

shaft surface under the transducer poles A and BRing torductor for measuring

torque on ship propeller shafts

(shaft diameter ca 500 mm)

(Courtesy ASEA Brown

Boveri AG)

Principal designs of coaxial torque sensors

Schematic diagram of data processing

electronics of a torque sensor

Extensometer (a) Construction of strain sensing element using

amorphous ribbon wound core (b) configuration of lumped

windings

∆E effect of an amorphous FeNi-based

alloy (Fe40 Ni38 Mo4 B18) Hs saturation

field

Magnetically tunable delay line

Torque Sensors using Amorphous wire

Sixtus tonk효과(large Barkhausen효과)

Hysteresis loops of a Wiegand wire for different reset fields

Curie 온도 및Hopkinson효과

Relation between normalised

saturation polarisation and

normalised Curie temperature

Permeability of a Mn-Zn ferrite as

a function of temperature and field

strength

Conclusions

1) Magnetic sensor 는 자동차 공장자동화 항공우주 및 군사용으로많이 사용되고 있다

2) 새로운 소재개발은 자기센서의 성능개발에 직접적인 영향을 준다2) 새로운 소재개발은 자기센서의 성능개발에 직접적인 영향을 준다

3) 센서의 개발을 위해서는 다양한 전공지식이 요구된다

(물리학 재료공학 기계공학 전자공학)

4) 센서분야가 고부가가치를 창출하는 부품사업이다

5) 핵심부품을 생산하는 중소기업의 item으로도 적절하다

γγ

Sensor with yoke Change in the magnetic flux with

varying air gap Continuous lines

minimum air gap dashed lines

maximum air gap

C-shaped sensor

Sensor with radially

magnetized

permanent magnet

Signal Conditioning

Output voltage U of a DC-excited sensor with permanent

magnets when a single iron object passes by

Schematic electrical diagram of an inductive sensor

Linear Variable Differential Transformer

AC-Excited Sensors for Linear Movement

Principle of construction of an LVDT

Electrical circuit of an LVDT

tIMtNU dd dd sdotminus=sdotminus= φ

tIMtIMUUU dd dd 1212 sdotminussdot=minus=

tIMMU dd)( 12 sdotminus=

)(12 xMMMM =minus=

tIxMU dd)( sdot= tI

UxM

dd)( =

Signal Conditioning

power supply

carrier gen

autoampcontrol

LVDTcarrieramp

demod-ulator

phase

shifter

power supply

carrier gen

passivedemod-ulator

LVDTDCamp

Block diagram of a carrier amplifier system

Block diagram of a DC amplifier system

Variable Inductive Sensors

Principle of construction

of the VLP sensor

Principle of a bridge

circuit

lANL r 20 sdotsdotsdot= micromicro

21 BA UUU minus=

21)i(ii( 211 minus+sdot= LLLUU BA ωωω

)21))()((( minus∆minus+∆+∆+sdot= LLLLLLUU BA

)212)(( minus∆+sdot= LLLUU )212)(( minus∆+sdot= LLLUU BA

LLUU BA 21 ∆sdotsdot=

llLL ∆sdot=∆ d d

llLLUU BA ∆sdotsdot= d d)2(1

Applications and Properties

Principle of a construction of a force transducer

(courtesy Hottinger Baldwin Messtechnik)

Vibrationacceleration sensor

Signal Conditioning

Schematic electrical diagram of a force transducer connected with an

amplifier (courtesy Hottinger Baldwin Messtechnik GmbH)

Variable Gap Sensors

)( FeFe2

0 LLllANL micromicromicro +sdotsdot=

FeFe2

0max lANL sdotsdotsdot= micromicro

Construction of a variable gap sensor

Characteristic of a variable gap sensor

Construction of a differential

cross-anchor sensor

Output voltage U versus core

position x plusmn a limits of the

linear rage

Applications of differential cross-anchor sensors

AC-excited Sensors for Rotary Movements

Principle of construction of a synchro

α cos10 sdotsdot= UKU y

)120-( cos10 degsdotsdot= αUKU z

)240-( cos10 degsdotsdot= αUKU x

)120-( sin3100 degsdotsdotsdot=minus= αKUUUU yxyx

)240-( sin3100 degsdotsdotsdot=minus= αKUUUU zyzy

α sin3100 sdotsdotsdot=minus= KUUUU xzxz

Application to the Torque Sensor

Principle of construction of a torque-type synchro

Torque versus angular

difference

)( sin~ rt αα minussdotKM

)( cos~ rt1r αα minussdotUU

Principle of construction of a control-type sensor

Output voltage versus

angular difference

Principle of construction of a differential sychro

Eddy Current Sensors

tBE dd curl minus=JH = curl

0 div =BH(H)B sdot= micro

E(E)J sdot= σ

A B curl= A B curl=

tdd- A E =

)dd( tAJ minus= σ

tdd curl curl AA σmicro minus=

AA) σωmicro iminus= curl )(curl(1

AA) σωmicro i=∆)((1

Eddy Current Tachometer

Construction of a speedometer (courtesy VDO Adolf Schinding AG) 1) spindle 2) bearing

3) holding spring 4) iron yoke 5) eddy current cup 6) shaft of the magnet 7) support of

the magnet 8) temperature compensation 9) permanent magnet 10) torsion spring

Proximity Sensors

Schematic diagram of a proximity sensor

Output current of a proximity switch versus distance

Inductive Flowmeters

)( Btimessdot= υqF

EqF sdot=BE times=υ

)(ds Btimes== υEU )(ds Btimes== υEU

)( Bd timessdot= υU

Bsdotsdotsdot= υdKU

Development of magnetic phase detection

sensor for steam generator tube

Dirac Son1 Kwan-Sang Ryu2 Duck-Gun Park3

1Hannam University Daejeon Rep of Korea2Korea Research Institute of Standards and Science Daejeon Rep of Korea3KoreaAtomic Energy Research Institute Daejeon Rep of Korea

Introduction

The layout of pressurized water reactor (PWR) components

Primary side Secondary side (non-radioactive side)(radioactive side)

The Structure of SG(Steam Generator)(degradation mechanism)

Secondary SidePrimary Side

SCC

A B

A-B

Steam outlet

Anti-vibration

SCC

Fretting

Wall thinning

IGA

U-bend

In commercial power plants SG- height up to 21 m - weight up to 800 tons - 2~4 sets of SG were installed - SG can contain from 3000 to

16000 tubes each about 20 mmin diameter

Primary coolant outlet Primary coolant inlet

Anti-vibrationbars

Tubesupportplate

Tubesheet

IGA

SCC

Pitting

SCC

Inside Tubesheet

Top of Tubesheet

by SSHwang of KAERI

Denting

Sludge pile

in diameter

The SGT is made of nickel basedInconel alloy which is composed of 75 Ni 165Cr and 815Fe

-Degradation mechanism corrosion pitting denting inter granular attack

-Inspection Eddy current Testing(ECT)

Permeability Variation Clusters (PVC)

(Ferro-magnetic phase)

-005

000

005

010

015

m (emug)

1-1

-002

000

002

004

006

008

m (emug)

1-2

-1000 -500 0 500 1000

-015

-010

-005

H ( Am )

-1000 -500 0 500 1000

-006

-004

-002

H ( Am )

The hystresis loop in the fragment of PVC parts of Kori-1 retired SG tube

-004

-002

000

002

004

006

M (emug)

Inconel 600 tested at RT

under tensile stress

1 2 3

4 5 6

7 8 9-004

-002

000

002

004

006

M(emug)

Inconel 600 Heat treated at

602 oC under tensile stress

1 2 3

How can we detect magnetic phase

(PVC)selectively from the flaws in SGT

-3000 -2000 -1000 0 1000 2000 3000

-006

H (Oe)

7 8 9

10 11 12

-3000 -2000 -1000 0 1000 2000 3000

-006

-004

H(Oe)

4 5 6

7 8 9

The hysteresis loop of the tensile tested specimen at room temperature (a) and tensile tested at high temperature (b)

The magnetic phase can be created under the high temperature andpressure conditions which is correspond to the stress corrosion crackingin the SG tube in the NPP(Bruemmer SM Charlot LA amp Henager CH (1988) Corrosion 782)

Principle of ECT

If we can separate magnetic phase selectively from the

flaws using magnetic sensor the reliability of EC in SGT

inspection will be greatly enhanced

Structure of the permeability

sensor

Dimension and photograph of U-shape

sensing yoke

Design of Magnetic Sensor for PVC

sensor sensing yoke

Photograph of the completed sensor front side (above) and rear side (bottom)

R11R12

R10

R8

R6

R9

R13

R7

R14

C18

1 n

C17

C20

C21

D2

DIODE

SIN COS

-

+

U-2A

4

13

2

-

+

U-2B

75

6

8

-

+

U-3A

13

2

8

+5VC19

104

+5V

Schematic diagram of the sensor system

Electronic Circuit of Magnetic Sensor

R20

R

R21

R

-

+

U5AD797

3

26

74

U6

D1

S12

GND3

+VCC4VCC5

IN6

-VCC7

S28

C41

R13

R26

R18

R25

R2210 Ω

R16

R14

R17

10 k

R15

R27

R32

R28

R33

R29

R34

5 k

R30

C29

C37

104

C32473

C39473C40

104

C33

104

C21

104C23

104

C25

104

C26

104

C30

104

C31

104

C35

104

C36

104

C27

104

C28

104

C34

104

C38

104

D3

DIODE

L1

1

2

L2

1

2

L3

1

2

4

-

+

U-4A

4

13

2

-

+

U-4B

75

6

8

-

+

U-5A

4

13

2

-

+

U-5B

75

6

8

-

+

U-6A

4

13

2

-

+

U-6B

75

6

8

C22

104

-5V

+5V

+5V

+5V

+5V

+5V

+5V

U7

D1

S12

GND3

+VCC4

VCC5

IN6

-VCC7

S28

+5V

-5V

-5V

-5V

-5V

-5V

-5V

-5V

-5V

R19

R24

R

R23

R

C24

OUT(X)

OUT(Y)

R1

20 kR210 k

R3

20 kR410 k

C1

104

C8

104

REF43

OUT(X)

OUT(Y)

REF43

U2

+Vcc1

CH02

CH13

CH24

CH35

COMM6

SHDN7

Vref8

+Vcc9

GND10

GND11

DOUT12BUSY13DIN14CS15

DIN16

-

+

U-1A

13

2

8

-

+

U-1B

4

75

6

C410 uF

C5104

DOUT

C210uF

C6104

C3104

DCLK

C7104

DIN

C10

01uF

CS

BUSY

C14 10uF

J1

CON6

123456

D1

DIODE

R5

47K

C9

10uF

C1310uF

Y1

OSC

OUT3

GND2

VCC4

U3

RSTVPP1

GND10

VCC20

XTAL15

XTAL24

P10AIN012P11AIN113P1214P1315P1416P1517P1618P1719

P30RXD2

P31TXD3

P32INT06

P33INT17

P34T08

P35T19

P3711

U4

C1+1

C1-3

C2+4

C2-5

VCC16

GND15

V+2

V-6

R1OUT12

R2OUT9

T1IN11

T2IN10

R1IN13

R2IN8

T1OUT14

T2OUT7

C12 10uF

C16

01uF

C15 10uF

C11

01uF

-5V

+5V

+5V

+5V

+5V

+5V

+5V

+5V

RST

OSC

OSC

RST

DCLKCSDINBUSYDOUT

U1

IN2

GND

4

OUT6

TEMP3

TRIM5

-5V

+5V

Electronic circuit diagram of the magnetic sensor

Photograph of the completed measuring system data acquisition

software in PC and probe scanning system

Experimental Setup for Magnetic Sensor

Reference material Scanning System Software LabVIEW

Reference Material (1) Normal defects and PVCs

Longitudinal and transverse defects

Def W L D Remarks

1 02 500 0213 (20 ) Inner defects

2 02 500 0427 (40 )

3 02 500 0213 (20 )Outer defectsPVC(1018)4 02 500 0427 (40 )

5 02 500 0639 (60 )

6 02 500 0852 (80 )

7 02 500 0639 (60 ) Inner defects

8 02 500 0852 (80 )

- 1 and 2 are inner defects

- 345 and 6 are outer defects with PVC

- 7 and 8 are inner defects

PVC

PVC

Defect Defect

For longitudinal defects and PVC For circumferential defects and PVC

ECT is very difficult to detect circumferential defects

We can distinguish PVCs and defects and longitudinal and circumferential defects

Flux-gate Magnetometer

One core sensor Two core sensor

3-축 flux-gate Magnetometer의 계략도

Sensorpia Co

pro

cess

or(

AV

R)

Sensor 1

RS422

Interface

Mic

ro-p

roce

ssor(

AV

R)

Sensor 2

Sensor 3

Interface

조립된 마그네토미터의 사진

Sensorpia Co

Analog PCB

Digital PCB

Sensorpia Co선형도(linearity)

10

20

30

40

50

60

y-axis

Magnetometer Output (microT)

-60 -50 -40 -30 -20 -10 0 10 20 30 40 50 60

-60

-50

-40

-30

-20

-10

0

10

Y-axis y=099946 x+0015STD 106E-4

Magnetometer Output (

Applied Magnetic Field (microT)

마그네토미터의 noise 특성 Sensorpia Co

1

10

100

y-axis

Magnetometer noise (nT)

0 1 2 3 4 5 6

1E-4

1E-3

001

01

Magnetometer noise (nT)

Frequency (Hz)

Magnetometer for KoDSAT

-150 -100 -50 0 50 100 150

-15

-10

-5

0

5

10

15

Magnetic Moment (Am

2)

Current (mA)

After Thermal Cycle Test

Measured

Resistance 193 ohm

Photograph of Magnetic torquer

Photograph of KoDSAT

Photograph of

3-axis Fluxgate

Magnetometer

Photograph of Magnetic torquer

Application of magnetometer

Moon magnetic fieldmeasurement

Telescope with direction indication

Joule Effect (Magnetostriction)

ϕ2cosel

l=

∆

0=∆

+∆

+∆

b

b

a

a

l

l

Actuator using Terfenol-D

00

05

10

B (T)

800

1000

1200

1400

1600

Magnetostriction (ppm)

-100 -50 0 50 100

-10

-05

00

B (T)

H (kAm)

2 MPa

4 MPa

6 MPa

8 MPa

10 MPa

12 MPa

-100 -50 0 50 100

-200

0

200

400

600

Magnetostriction (ppm)

H (kAm)

2 MPa

4 MPa

6 MPa

8 MPa

10 MPa

12 MPa

600

700

800

900

1000

-4 -3 -2 -1 0 1 2 3 4

0

10

20

30

40

50

60

Displacement (m

icro meter)

I (A)

FIELD

9 kAm

12 kAm

16 kAm

20 kAm

24 kAm

38 kAm

-50 -40 -30 -20 -10 0 10 20 30 40 50

-100

0

100

200

300

400

500

L (PPM)

H (kAm)

9 kAm

12 kAm

16 kAm

20 kAm

24 kAm

38 kAm

Magnetostrictive displacement sensor

Hysteresis loops under

tensile stress σ

(a) Crystalline 68 NiFe

λs = +25 10-6

(b) crystalline pure Ni λs

= -35 10-6

Villari Effect ( Inverse of Joule Effect)

= -35 10-6

(c) amorphous Co-based

alloy

λs = -35 10-6

ϕσλ 2sin2

3sdotsdot= smeE

γ

Permeability depending on the stress

σλmicromicro

1

3

2

Y

J

so

s

r =

γ

Calculated magnetization curves under stress

Variation of magnetization curve by an applied

tensile force (Co-based amorphous alloy)

Alloy Requirement

Materials for magnetoelastic sensors

Why amorphous magnetic materials are important

Stress-strain curves of several materials

Coercivity and hardness of several materials

Principles of magnetoelastic sensors

Non-contact torque sensor

Principle of cross torductor torque

sensor and flux pattern of sensor

poles on the surface of a shaft

a) without and b)with torsional load

Equivalent magnetic circuit of

cross type torque sensor

Helices of principal tensile and compressive stress on the surface of

a shaft subjected to torsion [32] Correlated changes of permeability

are detected by four-branch yoke system with sensing coils 123

and 4 and a common excitation pole

Examples of torque sensors

Four-branch type torque sensor

heads Pole structures realized

by commercial multi-pole

ferrites 14 and 18 min in

diameter (diameter of sensor

h e a d 1 7 a n d 2 4 m m

respectively) respectively)

Principle of Ring Torductor torque transducer

(a b) Physical structure (c) evolution of the

shaft surface under the transducer poles A and BRing torductor for measuring

torque on ship propeller shafts

(shaft diameter ca 500 mm)

(Courtesy ASEA Brown

Boveri AG)

Principal designs of coaxial torque sensors

Schematic diagram of data processing

electronics of a torque sensor

Extensometer (a) Construction of strain sensing element using

amorphous ribbon wound core (b) configuration of lumped

windings

∆E effect of an amorphous FeNi-based

alloy (Fe40 Ni38 Mo4 B18) Hs saturation

field

Magnetically tunable delay line

Torque Sensors using Amorphous wire

Sixtus tonk효과(large Barkhausen효과)

Hysteresis loops of a Wiegand wire for different reset fields

Curie 온도 및Hopkinson효과

Relation between normalised

saturation polarisation and

normalised Curie temperature

Permeability of a Mn-Zn ferrite as

a function of temperature and field

strength

Conclusions

1) Magnetic sensor 는 자동차 공장자동화 항공우주 및 군사용으로많이 사용되고 있다

2) 새로운 소재개발은 자기센서의 성능개발에 직접적인 영향을 준다2) 새로운 소재개발은 자기센서의 성능개발에 직접적인 영향을 준다

3) 센서의 개발을 위해서는 다양한 전공지식이 요구된다

(물리학 재료공학 기계공학 전자공학)

4) 센서분야가 고부가가치를 창출하는 부품사업이다

5) 핵심부품을 생산하는 중소기업의 item으로도 적절하다

C-shaped sensor

Sensor with radially

magnetized

permanent magnet

Signal Conditioning

Output voltage U of a DC-excited sensor with permanent

magnets when a single iron object passes by

Schematic electrical diagram of an inductive sensor

Linear Variable Differential Transformer

AC-Excited Sensors for Linear Movement

Principle of construction of an LVDT

Electrical circuit of an LVDT

tIMtNU dd dd sdotminus=sdotminus= φ

tIMtIMUUU dd dd 1212 sdotminussdot=minus=

tIMMU dd)( 12 sdotminus=

)(12 xMMMM =minus=

tIxMU dd)( sdot= tI

UxM

dd)( =

Signal Conditioning

power supply

carrier gen

autoampcontrol

LVDTcarrieramp

demod-ulator

phase

shifter

power supply

carrier gen

passivedemod-ulator

LVDTDCamp

Block diagram of a carrier amplifier system

Block diagram of a DC amplifier system

Variable Inductive Sensors

Principle of construction

of the VLP sensor

Principle of a bridge

circuit

lANL r 20 sdotsdotsdot= micromicro

21 BA UUU minus=

21)i(ii( 211 minus+sdot= LLLUU BA ωωω

)21))()((( minus∆minus+∆+∆+sdot= LLLLLLUU BA

)212)(( minus∆+sdot= LLLUU )212)(( minus∆+sdot= LLLUU BA

LLUU BA 21 ∆sdotsdot=

llLL ∆sdot=∆ d d

llLLUU BA ∆sdotsdot= d d)2(1

Applications and Properties

Principle of a construction of a force transducer

(courtesy Hottinger Baldwin Messtechnik)

Vibrationacceleration sensor

Signal Conditioning

Schematic electrical diagram of a force transducer connected with an

amplifier (courtesy Hottinger Baldwin Messtechnik GmbH)

Variable Gap Sensors

)( FeFe2

0 LLllANL micromicromicro +sdotsdot=

FeFe2

0max lANL sdotsdotsdot= micromicro

Construction of a variable gap sensor

Characteristic of a variable gap sensor

Construction of a differential

cross-anchor sensor

Output voltage U versus core

position x plusmn a limits of the

linear rage

Applications of differential cross-anchor sensors

AC-excited Sensors for Rotary Movements

Principle of construction of a synchro

α cos10 sdotsdot= UKU y

)120-( cos10 degsdotsdot= αUKU z

)240-( cos10 degsdotsdot= αUKU x

)120-( sin3100 degsdotsdotsdot=minus= αKUUUU yxyx

)240-( sin3100 degsdotsdotsdot=minus= αKUUUU zyzy

α sin3100 sdotsdotsdot=minus= KUUUU xzxz

Application to the Torque Sensor

Principle of construction of a torque-type synchro

Torque versus angular

difference

)( sin~ rt αα minussdotKM

)( cos~ rt1r αα minussdotUU

Principle of construction of a control-type sensor

Output voltage versus

angular difference

Principle of construction of a differential sychro

Eddy Current Sensors

tBE dd curl minus=JH = curl

0 div =BH(H)B sdot= micro

E(E)J sdot= σ

A B curl= A B curl=

tdd- A E =

)dd( tAJ minus= σ

tdd curl curl AA σmicro minus=

AA) σωmicro iminus= curl )(curl(1

AA) σωmicro i=∆)((1

Eddy Current Tachometer

Construction of a speedometer (courtesy VDO Adolf Schinding AG) 1) spindle 2) bearing

3) holding spring 4) iron yoke 5) eddy current cup 6) shaft of the magnet 7) support of

the magnet 8) temperature compensation 9) permanent magnet 10) torsion spring

Proximity Sensors

Schematic diagram of a proximity sensor

Output current of a proximity switch versus distance

Inductive Flowmeters

)( Btimessdot= υqF

EqF sdot=BE times=υ

)(ds Btimes== υEU )(ds Btimes== υEU

)( Bd timessdot= υU

Bsdotsdotsdot= υdKU

Development of magnetic phase detection

sensor for steam generator tube

Dirac Son1 Kwan-Sang Ryu2 Duck-Gun Park3

1Hannam University Daejeon Rep of Korea2Korea Research Institute of Standards and Science Daejeon Rep of Korea3KoreaAtomic Energy Research Institute Daejeon Rep of Korea

Introduction

The layout of pressurized water reactor (PWR) components

Primary side Secondary side (non-radioactive side)(radioactive side)

The Structure of SG(Steam Generator)(degradation mechanism)

Secondary SidePrimary Side

SCC

A B

A-B

Steam outlet

Anti-vibration

SCC

Fretting

Wall thinning

IGA

U-bend

In commercial power plants SG- height up to 21 m - weight up to 800 tons - 2~4 sets of SG were installed - SG can contain from 3000 to

16000 tubes each about 20 mmin diameter

Primary coolant outlet Primary coolant inlet

Anti-vibrationbars

Tubesupportplate

Tubesheet

IGA

SCC

Pitting

SCC

Inside Tubesheet

Top of Tubesheet

by SSHwang of KAERI

Denting

Sludge pile

in diameter

The SGT is made of nickel basedInconel alloy which is composed of 75 Ni 165Cr and 815Fe

-Degradation mechanism corrosion pitting denting inter granular attack

-Inspection Eddy current Testing(ECT)

Permeability Variation Clusters (PVC)

(Ferro-magnetic phase)

-005

000

005

010

015

m (emug)

1-1

-002

000

002

004

006

008

m (emug)

1-2

-1000 -500 0 500 1000

-015

-010

-005

H ( Am )

-1000 -500 0 500 1000

-006

-004

-002

H ( Am )

The hystresis loop in the fragment of PVC parts of Kori-1 retired SG tube

-004

-002

000

002

004

006

M (emug)

Inconel 600 tested at RT

under tensile stress

1 2 3

4 5 6

7 8 9-004

-002

000

002

004

006

M(emug)

Inconel 600 Heat treated at

602 oC under tensile stress

1 2 3

How can we detect magnetic phase

(PVC)selectively from the flaws in SGT

-3000 -2000 -1000 0 1000 2000 3000

-006

H (Oe)

7 8 9

10 11 12

-3000 -2000 -1000 0 1000 2000 3000

-006

-004

H(Oe)

4 5 6

7 8 9

The hysteresis loop of the tensile tested specimen at room temperature (a) and tensile tested at high temperature (b)

The magnetic phase can be created under the high temperature andpressure conditions which is correspond to the stress corrosion crackingin the SG tube in the NPP(Bruemmer SM Charlot LA amp Henager CH (1988) Corrosion 782)

Principle of ECT

If we can separate magnetic phase selectively from the

flaws using magnetic sensor the reliability of EC in SGT

inspection will be greatly enhanced

Structure of the permeability

sensor

Dimension and photograph of U-shape

sensing yoke

Design of Magnetic Sensor for PVC

sensor sensing yoke

Photograph of the completed sensor front side (above) and rear side (bottom)

R11R12

R10

R8

R6

R9

R13

R7

R14

C18

1 n

C17

C20

C21

D2

DIODE

SIN COS

-

+

U-2A

4

13

2

-

+

U-2B

75

6

8

-

+

U-3A

13

2

8

+5VC19

104

+5V

Schematic diagram of the sensor system

Electronic Circuit of Magnetic Sensor

R20

R

R21

R

-

+

U5AD797

3

26

74

U6

D1

S12

GND3

+VCC4VCC5

IN6

-VCC7

S28

C41

R13

R26

R18

R25

R2210 Ω

R16

R14

R17

10 k

R15

R27

R32

R28

R33

R29

R34

5 k

R30

C29

C37

104

C32473

C39473C40

104

C33

104

C21

104C23

104

C25

104

C26

104

C30

104

C31

104

C35

104

C36

104

C27

104

C28

104

C34

104

C38

104

D3

DIODE

L1

1

2

L2

1

2

L3

1

2

4

-

+

U-4A

4

13

2

-

+

U-4B

75

6

8

-

+

U-5A

4

13

2

-

+

U-5B

75

6

8

-

+

U-6A

4

13

2

-

+

U-6B

75

6

8

C22

104

-5V

+5V

+5V

+5V

+5V

+5V

+5V

U7

D1

S12

GND3

+VCC4

VCC5

IN6

-VCC7

S28

+5V

-5V

-5V

-5V

-5V

-5V

-5V

-5V

-5V

R19

R24

R

R23

R

C24

OUT(X)

OUT(Y)

R1

20 kR210 k

R3

20 kR410 k

C1

104

C8

104

REF43

OUT(X)

OUT(Y)

REF43

U2

+Vcc1

CH02

CH13

CH24

CH35

COMM6

SHDN7

Vref8

+Vcc9

GND10

GND11

DOUT12BUSY13DIN14CS15

DIN16

-

+

U-1A

13

2

8

-

+

U-1B

4

75

6

C410 uF

C5104

DOUT

C210uF

C6104

C3104

DCLK

C7104

DIN

C10

01uF

CS

BUSY

C14 10uF

J1

CON6

123456

D1

DIODE

R5

47K

C9

10uF

C1310uF

Y1

OSC

OUT3

GND2

VCC4

U3

RSTVPP1

GND10

VCC20

XTAL15

XTAL24

P10AIN012P11AIN113P1214P1315P1416P1517P1618P1719

P30RXD2

P31TXD3

P32INT06

P33INT17

P34T08

P35T19

P3711

U4

C1+1

C1-3

C2+4

C2-5

VCC16

GND15

V+2

V-6

R1OUT12

R2OUT9

T1IN11

T2IN10

R1IN13

R2IN8

T1OUT14

T2OUT7

C12 10uF

C16

01uF

C15 10uF

C11

01uF

-5V

+5V

+5V

+5V

+5V

+5V

+5V

+5V

RST

OSC

OSC

RST

DCLKCSDINBUSYDOUT

U1

IN2

GND

4

OUT6

TEMP3

TRIM5

-5V

+5V

Electronic circuit diagram of the magnetic sensor

Photograph of the completed measuring system data acquisition

software in PC and probe scanning system

Experimental Setup for Magnetic Sensor

Reference material Scanning System Software LabVIEW

Reference Material (1) Normal defects and PVCs

Longitudinal and transverse defects

Def W L D Remarks

1 02 500 0213 (20 ) Inner defects

2 02 500 0427 (40 )

3 02 500 0213 (20 )Outer defectsPVC(1018)4 02 500 0427 (40 )

5 02 500 0639 (60 )

6 02 500 0852 (80 )

7 02 500 0639 (60 ) Inner defects

8 02 500 0852 (80 )

- 1 and 2 are inner defects

- 345 and 6 are outer defects with PVC

- 7 and 8 are inner defects

PVC

PVC

Defect Defect

For longitudinal defects and PVC For circumferential defects and PVC

ECT is very difficult to detect circumferential defects

We can distinguish PVCs and defects and longitudinal and circumferential defects

Flux-gate Magnetometer

One core sensor Two core sensor

3-축 flux-gate Magnetometer의 계략도

Sensorpia Co

pro

cess

or(

AV

R)

Sensor 1

RS422

Interface

Mic

ro-p

roce

ssor(

AV

R)

Sensor 2

Sensor 3

Interface

조립된 마그네토미터의 사진

Sensorpia Co

Analog PCB

Digital PCB

Sensorpia Co선형도(linearity)

10

20

30

40

50

60

y-axis

Magnetometer Output (microT)

-60 -50 -40 -30 -20 -10 0 10 20 30 40 50 60

-60

-50

-40

-30

-20

-10

0

10

Y-axis y=099946 x+0015STD 106E-4

Magnetometer Output (

Applied Magnetic Field (microT)

마그네토미터의 noise 특성 Sensorpia Co

1

10

100

y-axis

Magnetometer noise (nT)

0 1 2 3 4 5 6

1E-4

1E-3

001

01

Magnetometer noise (nT)

Frequency (Hz)

Magnetometer for KoDSAT

-150 -100 -50 0 50 100 150

-15

-10

-5

0

5

10

15

Magnetic Moment (Am

2)

Current (mA)

After Thermal Cycle Test

Measured

Resistance 193 ohm

Photograph of Magnetic torquer

Photograph of KoDSAT

Photograph of

3-axis Fluxgate

Magnetometer

Photograph of Magnetic torquer

Application of magnetometer

Moon magnetic fieldmeasurement

Telescope with direction indication

Joule Effect (Magnetostriction)

ϕ2cosel

l=

∆

0=∆

+∆

+∆

b

b

a

a

l

l

Actuator using Terfenol-D

00

05

10

B (T)

800

1000

1200

1400

1600

Magnetostriction (ppm)

-100 -50 0 50 100

-10

-05

00

B (T)

H (kAm)

2 MPa

4 MPa

6 MPa

8 MPa

10 MPa

12 MPa

-100 -50 0 50 100

-200

0

200

400

600

Magnetostriction (ppm)

H (kAm)

2 MPa

4 MPa

6 MPa

8 MPa

10 MPa

12 MPa

600

700

800

900

1000

-4 -3 -2 -1 0 1 2 3 4

0

10

20

30

40

50

60

Displacement (m

icro meter)

I (A)

FIELD

9 kAm

12 kAm

16 kAm

20 kAm

24 kAm

38 kAm

-50 -40 -30 -20 -10 0 10 20 30 40 50

-100

0

100

200

300

400

500

L (PPM)

H (kAm)

9 kAm

12 kAm

16 kAm

20 kAm

24 kAm

38 kAm

Magnetostrictive displacement sensor

Hysteresis loops under

tensile stress σ

(a) Crystalline 68 NiFe

λs = +25 10-6

(b) crystalline pure Ni λs

= -35 10-6

Villari Effect ( Inverse of Joule Effect)

= -35 10-6

(c) amorphous Co-based

alloy

λs = -35 10-6

ϕσλ 2sin2

3sdotsdot= smeE

γ

Permeability depending on the stress

σλmicromicro

1

3

2

Y

J

so

s

r =

γ

Calculated magnetization curves under stress

Variation of magnetization curve by an applied

tensile force (Co-based amorphous alloy)

Alloy Requirement

Materials for magnetoelastic sensors

Why amorphous magnetic materials are important

Stress-strain curves of several materials

Coercivity and hardness of several materials

Principles of magnetoelastic sensors

Non-contact torque sensor

Principle of cross torductor torque

sensor and flux pattern of sensor

poles on the surface of a shaft

a) without and b)with torsional load

Equivalent magnetic circuit of

cross type torque sensor

Helices of principal tensile and compressive stress on the surface of

a shaft subjected to torsion [32] Correlated changes of permeability

are detected by four-branch yoke system with sensing coils 123

and 4 and a common excitation pole

Examples of torque sensors

Four-branch type torque sensor

heads Pole structures realized

by commercial multi-pole

ferrites 14 and 18 min in

diameter (diameter of sensor

h e a d 1 7 a n d 2 4 m m

respectively) respectively)

Principle of Ring Torductor torque transducer

(a b) Physical structure (c) evolution of the

shaft surface under the transducer poles A and BRing torductor for measuring

torque on ship propeller shafts

(shaft diameter ca 500 mm)

(Courtesy ASEA Brown

Boveri AG)

Principal designs of coaxial torque sensors

Schematic diagram of data processing

electronics of a torque sensor

Extensometer (a) Construction of strain sensing element using

amorphous ribbon wound core (b) configuration of lumped

windings

∆E effect of an amorphous FeNi-based

alloy (Fe40 Ni38 Mo4 B18) Hs saturation

field

Magnetically tunable delay line

Torque Sensors using Amorphous wire

Sixtus tonk효과(large Barkhausen효과)

Hysteresis loops of a Wiegand wire for different reset fields

Curie 온도 및Hopkinson효과

Relation between normalised

saturation polarisation and

normalised Curie temperature

Permeability of a Mn-Zn ferrite as

a function of temperature and field

strength

Conclusions

1) Magnetic sensor 는 자동차 공장자동화 항공우주 및 군사용으로많이 사용되고 있다

2) 새로운 소재개발은 자기센서의 성능개발에 직접적인 영향을 준다2) 새로운 소재개발은 자기센서의 성능개발에 직접적인 영향을 준다

3) 센서의 개발을 위해서는 다양한 전공지식이 요구된다

(물리학 재료공학 기계공학 전자공학)

4) 센서분야가 고부가가치를 창출하는 부품사업이다

5) 핵심부품을 생산하는 중소기업의 item으로도 적절하다

Signal Conditioning

Output voltage U of a DC-excited sensor with permanent

magnets when a single iron object passes by

Schematic electrical diagram of an inductive sensor

Linear Variable Differential Transformer

AC-Excited Sensors for Linear Movement

Principle of construction of an LVDT

Electrical circuit of an LVDT

tIMtNU dd dd sdotminus=sdotminus= φ

tIMtIMUUU dd dd 1212 sdotminussdot=minus=

tIMMU dd)( 12 sdotminus=

)(12 xMMMM =minus=

tIxMU dd)( sdot= tI

UxM

dd)( =

Signal Conditioning

power supply

carrier gen

autoampcontrol

LVDTcarrieramp

demod-ulator

phase

shifter

power supply

carrier gen

passivedemod-ulator

LVDTDCamp

Block diagram of a carrier amplifier system

Block diagram of a DC amplifier system

Variable Inductive Sensors

Principle of construction

of the VLP sensor

Principle of a bridge

circuit

lANL r 20 sdotsdotsdot= micromicro

21 BA UUU minus=

21)i(ii( 211 minus+sdot= LLLUU BA ωωω

)21))()((( minus∆minus+∆+∆+sdot= LLLLLLUU BA

)212)(( minus∆+sdot= LLLUU )212)(( minus∆+sdot= LLLUU BA

LLUU BA 21 ∆sdotsdot=

llLL ∆sdot=∆ d d

llLLUU BA ∆sdotsdot= d d)2(1

Applications and Properties

Principle of a construction of a force transducer

(courtesy Hottinger Baldwin Messtechnik)

Vibrationacceleration sensor

Signal Conditioning

Schematic electrical diagram of a force transducer connected with an

amplifier (courtesy Hottinger Baldwin Messtechnik GmbH)

Variable Gap Sensors

)( FeFe2

0 LLllANL micromicromicro +sdotsdot=

FeFe2

0max lANL sdotsdotsdot= micromicro

Construction of a variable gap sensor

Characteristic of a variable gap sensor

Construction of a differential

cross-anchor sensor

Output voltage U versus core

position x plusmn a limits of the

linear rage

Applications of differential cross-anchor sensors

AC-excited Sensors for Rotary Movements

Principle of construction of a synchro

α cos10 sdotsdot= UKU y

)120-( cos10 degsdotsdot= αUKU z

)240-( cos10 degsdotsdot= αUKU x

)120-( sin3100 degsdotsdotsdot=minus= αKUUUU yxyx

)240-( sin3100 degsdotsdotsdot=minus= αKUUUU zyzy

α sin3100 sdotsdotsdot=minus= KUUUU xzxz

Application to the Torque Sensor

Principle of construction of a torque-type synchro

Torque versus angular

difference

)( sin~ rt αα minussdotKM

)( cos~ rt1r αα minussdotUU

Principle of construction of a control-type sensor

Output voltage versus

angular difference

Principle of construction of a differential sychro

Eddy Current Sensors

tBE dd curl minus=JH = curl

0 div =BH(H)B sdot= micro

E(E)J sdot= σ

A B curl= A B curl=

tdd- A E =

)dd( tAJ minus= σ

tdd curl curl AA σmicro minus=

AA) σωmicro iminus= curl )(curl(1

AA) σωmicro i=∆)((1

Eddy Current Tachometer

Construction of a speedometer (courtesy VDO Adolf Schinding AG) 1) spindle 2) bearing

3) holding spring 4) iron yoke 5) eddy current cup 6) shaft of the magnet 7) support of

the magnet 8) temperature compensation 9) permanent magnet 10) torsion spring

Proximity Sensors

Schematic diagram of a proximity sensor

Output current of a proximity switch versus distance

Inductive Flowmeters

)( Btimessdot= υqF

EqF sdot=BE times=υ

)(ds Btimes== υEU )(ds Btimes== υEU

)( Bd timessdot= υU

Bsdotsdotsdot= υdKU

Development of magnetic phase detection

sensor for steam generator tube

Dirac Son1 Kwan-Sang Ryu2 Duck-Gun Park3

1Hannam University Daejeon Rep of Korea2Korea Research Institute of Standards and Science Daejeon Rep of Korea3KoreaAtomic Energy Research Institute Daejeon Rep of Korea

Introduction

The layout of pressurized water reactor (PWR) components

Primary side Secondary side (non-radioactive side)(radioactive side)

The Structure of SG(Steam Generator)(degradation mechanism)

Secondary SidePrimary Side

SCC

A B

A-B

Steam outlet

Anti-vibration

SCC

Fretting

Wall thinning

IGA

U-bend

In commercial power plants SG- height up to 21 m - weight up to 800 tons - 2~4 sets of SG were installed - SG can contain from 3000 to

16000 tubes each about 20 mmin diameter

Primary coolant outlet Primary coolant inlet

Anti-vibrationbars

Tubesupportplate

Tubesheet

IGA

SCC

Pitting

SCC

Inside Tubesheet

Top of Tubesheet

by SSHwang of KAERI

Denting

Sludge pile

in diameter

The SGT is made of nickel basedInconel alloy which is composed of 75 Ni 165Cr and 815Fe

-Degradation mechanism corrosion pitting denting inter granular attack

-Inspection Eddy current Testing(ECT)

Permeability Variation Clusters (PVC)

(Ferro-magnetic phase)

-005

000

005

010

015

m (emug)

1-1

-002

000

002

004

006

008

m (emug)

1-2

-1000 -500 0 500 1000

-015

-010

-005

H ( Am )

-1000 -500 0 500 1000

-006

-004

-002

H ( Am )

The hystresis loop in the fragment of PVC parts of Kori-1 retired SG tube

-004

-002

000

002

004

006

M (emug)

Inconel 600 tested at RT

under tensile stress

1 2 3

4 5 6

7 8 9-004

-002

000

002

004

006

M(emug)

Inconel 600 Heat treated at

602 oC under tensile stress

1 2 3

How can we detect magnetic phase

(PVC)selectively from the flaws in SGT

-3000 -2000 -1000 0 1000 2000 3000

-006

H (Oe)

7 8 9

10 11 12

-3000 -2000 -1000 0 1000 2000 3000

-006

-004

H(Oe)

4 5 6

7 8 9

The hysteresis loop of the tensile tested specimen at room temperature (a) and tensile tested at high temperature (b)

The magnetic phase can be created under the high temperature andpressure conditions which is correspond to the stress corrosion crackingin the SG tube in the NPP(Bruemmer SM Charlot LA amp Henager CH (1988) Corrosion 782)

Principle of ECT

If we can separate magnetic phase selectively from the

flaws using magnetic sensor the reliability of EC in SGT

inspection will be greatly enhanced

Structure of the permeability

sensor

Dimension and photograph of U-shape

sensing yoke

Design of Magnetic Sensor for PVC

sensor sensing yoke

Photograph of the completed sensor front side (above) and rear side (bottom)

R11R12

R10

R8

R6

R9

R13

R7

R14

C18

1 n

C17

C20

C21

D2

DIODE

SIN COS

-

+

U-2A

4

13

2

-

+

U-2B

75

6

8

-

+

U-3A

13

2

8

+5VC19

104

+5V

Schematic diagram of the sensor system

Electronic Circuit of Magnetic Sensor

R20

R

R21

R

-

+

U5AD797

3

26

74

U6

D1

S12

GND3

+VCC4VCC5

IN6

-VCC7

S28

C41

R13

R26

R18

R25

R2210 Ω

R16

R14

R17

10 k

R15

R27

R32

R28

R33

R29

R34

5 k

R30

C29

C37

104

C32473

C39473C40

104

C33

104

C21

104C23

104

C25

104

C26

104

C30

104

C31

104

C35

104

C36

104

C27

104

C28

104

C34

104

C38

104

D3

DIODE

L1

1

2

L2

1

2

L3

1

2

4

-

+

U-4A

4

13

2

-

+

U-4B

75

6

8

-

+

U-5A

4

13

2

-

+

U-5B

75

6

8

-

+

U-6A

4

13

2

-

+

U-6B

75

6

8

C22

104

-5V

+5V

+5V

+5V

+5V

+5V

+5V

U7

D1

S12

GND3

+VCC4

VCC5

IN6

-VCC7

S28

+5V

-5V

-5V

-5V

-5V

-5V

-5V

-5V

-5V

R19

R24

R

R23

R

C24

OUT(X)

OUT(Y)

R1

20 kR210 k

R3

20 kR410 k

C1

104

C8

104

REF43

OUT(X)

OUT(Y)

REF43

U2

+Vcc1

CH02

CH13

CH24

CH35

COMM6

SHDN7

Vref8

+Vcc9

GND10

GND11

DOUT12BUSY13DIN14CS15

DIN16

-

+

U-1A

13

2

8

-

+

U-1B

4

75

6

C410 uF

C5104

DOUT

C210uF

C6104

C3104

DCLK

C7104

DIN

C10

01uF

CS

BUSY

C14 10uF

J1

CON6

123456

D1

DIODE

R5

47K

C9

10uF

C1310uF

Y1

OSC

OUT3

GND2

VCC4

U3

RSTVPP1

GND10

VCC20

XTAL15

XTAL24

P10AIN012P11AIN113P1214P1315P1416P1517P1618P1719

P30RXD2

P31TXD3

P32INT06

P33INT17

P34T08

P35T19

P3711

U4

C1+1

C1-3

C2+4

C2-5

VCC16

GND15

V+2

V-6

R1OUT12

R2OUT9

T1IN11

T2IN10

R1IN13

R2IN8

T1OUT14

T2OUT7

C12 10uF

C16

01uF

C15 10uF

C11

01uF

-5V

+5V

+5V

+5V

+5V

+5V

+5V

+5V

RST

OSC

OSC

RST

DCLKCSDINBUSYDOUT

U1

IN2

GND

4

OUT6

TEMP3

TRIM5

-5V

+5V

Electronic circuit diagram of the magnetic sensor

Photograph of the completed measuring system data acquisition

software in PC and probe scanning system

Experimental Setup for Magnetic Sensor

Reference material Scanning System Software LabVIEW

Reference Material (1) Normal defects and PVCs

Longitudinal and transverse defects

Def W L D Remarks

1 02 500 0213 (20 ) Inner defects

2 02 500 0427 (40 )

3 02 500 0213 (20 )Outer defectsPVC(1018)4 02 500 0427 (40 )

5 02 500 0639 (60 )

6 02 500 0852 (80 )

7 02 500 0639 (60 ) Inner defects

8 02 500 0852 (80 )

- 1 and 2 are inner defects

- 345 and 6 are outer defects with PVC

- 7 and 8 are inner defects

PVC

PVC

Defect Defect

For longitudinal defects and PVC For circumferential defects and PVC

ECT is very difficult to detect circumferential defects

We can distinguish PVCs and defects and longitudinal and circumferential defects

Flux-gate Magnetometer

One core sensor Two core sensor

3-축 flux-gate Magnetometer의 계략도

Sensorpia Co

pro

cess

or(

AV

R)

Sensor 1

RS422

Interface

Mic

ro-p

roce

ssor(

AV

R)

Sensor 2

Sensor 3

Interface

조립된 마그네토미터의 사진

Sensorpia Co

Analog PCB

Digital PCB

Sensorpia Co선형도(linearity)

10

20

30

40

50

60

y-axis

Magnetometer Output (microT)

-60 -50 -40 -30 -20 -10 0 10 20 30 40 50 60

-60

-50

-40

-30

-20

-10

0

10

Y-axis y=099946 x+0015STD 106E-4

Magnetometer Output (

Applied Magnetic Field (microT)

마그네토미터의 noise 특성 Sensorpia Co

1

10

100

y-axis

Magnetometer noise (nT)

0 1 2 3 4 5 6

1E-4

1E-3

001

01

Magnetometer noise (nT)

Frequency (Hz)

Magnetometer for KoDSAT

-150 -100 -50 0 50 100 150

-15

-10

-5

0

5

10

15

Magnetic Moment (Am

2)

Current (mA)

After Thermal Cycle Test

Measured

Resistance 193 ohm

Photograph of Magnetic torquer

Photograph of KoDSAT

Photograph of

3-axis Fluxgate

Magnetometer

Photograph of Magnetic torquer

Application of magnetometer

Moon magnetic fieldmeasurement

Telescope with direction indication

Joule Effect (Magnetostriction)

ϕ2cosel

l=

∆

0=∆

+∆

+∆

b

b

a

a

l

l

Actuator using Terfenol-D

00

05

10

B (T)

800

1000

1200

1400

1600

Magnetostriction (ppm)

-100 -50 0 50 100

-10

-05

00

B (T)

H (kAm)

2 MPa

4 MPa

6 MPa

8 MPa

10 MPa

12 MPa

-100 -50 0 50 100

-200

0

200

400

600

Magnetostriction (ppm)

H (kAm)

2 MPa

4 MPa

6 MPa

8 MPa

10 MPa

12 MPa

600

700

800

900

1000

-4 -3 -2 -1 0 1 2 3 4

0

10

20

30

40

50

60

Displacement (m

icro meter)

I (A)

FIELD

9 kAm

12 kAm

16 kAm

20 kAm

24 kAm

38 kAm

-50 -40 -30 -20 -10 0 10 20 30 40 50

-100

0

100

200

300

400

500

L (PPM)

H (kAm)

9 kAm

12 kAm

16 kAm

20 kAm

24 kAm

38 kAm

Magnetostrictive displacement sensor

Hysteresis loops under

tensile stress σ

(a) Crystalline 68 NiFe

λs = +25 10-6

(b) crystalline pure Ni λs

= -35 10-6

Villari Effect ( Inverse of Joule Effect)

= -35 10-6

(c) amorphous Co-based

alloy

λs = -35 10-6

ϕσλ 2sin2

3sdotsdot= smeE

γ

Permeability depending on the stress

σλmicromicro

1

3

2

Y

J

so

s

r =

γ

Calculated magnetization curves under stress

Variation of magnetization curve by an applied

tensile force (Co-based amorphous alloy)

Alloy Requirement

Materials for magnetoelastic sensors

Why amorphous magnetic materials are important

Stress-strain curves of several materials

Coercivity and hardness of several materials

Principles of magnetoelastic sensors

Non-contact torque sensor

Principle of cross torductor torque

sensor and flux pattern of sensor

poles on the surface of a shaft

a) without and b)with torsional load

Equivalent magnetic circuit of

cross type torque sensor

Helices of principal tensile and compressive stress on the surface of

a shaft subjected to torsion [32] Correlated changes of permeability

are detected by four-branch yoke system with sensing coils 123

and 4 and a common excitation pole

Examples of torque sensors

Four-branch type torque sensor

heads Pole structures realized

by commercial multi-pole

ferrites 14 and 18 min in

diameter (diameter of sensor

h e a d 1 7 a n d 2 4 m m

respectively) respectively)

Principle of Ring Torductor torque transducer

(a b) Physical structure (c) evolution of the

shaft surface under the transducer poles A and BRing torductor for measuring

torque on ship propeller shafts

(shaft diameter ca 500 mm)

(Courtesy ASEA Brown

Boveri AG)

Principal designs of coaxial torque sensors

Schematic diagram of data processing

electronics of a torque sensor

Extensometer (a) Construction of strain sensing element using

amorphous ribbon wound core (b) configuration of lumped

windings

∆E effect of an amorphous FeNi-based

alloy (Fe40 Ni38 Mo4 B18) Hs saturation

field

Magnetically tunable delay line

Torque Sensors using Amorphous wire

Sixtus tonk효과(large Barkhausen효과)

Hysteresis loops of a Wiegand wire for different reset fields

Curie 온도 및Hopkinson효과

Relation between normalised

saturation polarisation and

normalised Curie temperature

Permeability of a Mn-Zn ferrite as

a function of temperature and field

strength

Conclusions

1) Magnetic sensor 는 자동차 공장자동화 항공우주 및 군사용으로많이 사용되고 있다

2) 새로운 소재개발은 자기센서의 성능개발에 직접적인 영향을 준다2) 새로운 소재개발은 자기센서의 성능개발에 직접적인 영향을 준다

3) 센서의 개발을 위해서는 다양한 전공지식이 요구된다

(물리학 재료공학 기계공학 전자공학)

4) 센서분야가 고부가가치를 창출하는 부품사업이다

5) 핵심부품을 생산하는 중소기업의 item으로도 적절하다

Schematic electrical diagram of an inductive sensor

Linear Variable Differential Transformer

AC-Excited Sensors for Linear Movement

Principle of construction of an LVDT

Electrical circuit of an LVDT

tIMtNU dd dd sdotminus=sdotminus= φ

tIMtIMUUU dd dd 1212 sdotminussdot=minus=

tIMMU dd)( 12 sdotminus=

)(12 xMMMM =minus=

tIxMU dd)( sdot= tI

UxM

dd)( =

Signal Conditioning

power supply

carrier gen

autoampcontrol

LVDTcarrieramp

demod-ulator

phase

shifter

power supply

carrier gen

passivedemod-ulator

LVDTDCamp

Block diagram of a carrier amplifier system

Block diagram of a DC amplifier system

Variable Inductive Sensors

Principle of construction

of the VLP sensor

Principle of a bridge

circuit

lANL r 20 sdotsdotsdot= micromicro

21 BA UUU minus=

21)i(ii( 211 minus+sdot= LLLUU BA ωωω

)21))()((( minus∆minus+∆+∆+sdot= LLLLLLUU BA

)212)(( minus∆+sdot= LLLUU )212)(( minus∆+sdot= LLLUU BA

LLUU BA 21 ∆sdotsdot=

llLL ∆sdot=∆ d d

llLLUU BA ∆sdotsdot= d d)2(1

Applications and Properties

Principle of a construction of a force transducer

(courtesy Hottinger Baldwin Messtechnik)

Vibrationacceleration sensor

Signal Conditioning

Schematic electrical diagram of a force transducer connected with an

amplifier (courtesy Hottinger Baldwin Messtechnik GmbH)

Variable Gap Sensors

)( FeFe2

0 LLllANL micromicromicro +sdotsdot=

FeFe2

0max lANL sdotsdotsdot= micromicro

Construction of a variable gap sensor

Characteristic of a variable gap sensor

Construction of a differential

cross-anchor sensor

Output voltage U versus core

position x plusmn a limits of the

linear rage

Applications of differential cross-anchor sensors

AC-excited Sensors for Rotary Movements

Principle of construction of a synchro

α cos10 sdotsdot= UKU y

)120-( cos10 degsdotsdot= αUKU z

)240-( cos10 degsdotsdot= αUKU x

)120-( sin3100 degsdotsdotsdot=minus= αKUUUU yxyx

)240-( sin3100 degsdotsdotsdot=minus= αKUUUU zyzy

α sin3100 sdotsdotsdot=minus= KUUUU xzxz

Application to the Torque Sensor

Principle of construction of a torque-type synchro

Torque versus angular

difference

)( sin~ rt αα minussdotKM

)( cos~ rt1r αα minussdotUU

Principle of construction of a control-type sensor

Output voltage versus

angular difference

Principle of construction of a differential sychro

Eddy Current Sensors

tBE dd curl minus=JH = curl

0 div =BH(H)B sdot= micro

E(E)J sdot= σ

A B curl= A B curl=

tdd- A E =

)dd( tAJ minus= σ

tdd curl curl AA σmicro minus=

AA) σωmicro iminus= curl )(curl(1

AA) σωmicro i=∆)((1

Eddy Current Tachometer

Construction of a speedometer (courtesy VDO Adolf Schinding AG) 1) spindle 2) bearing

3) holding spring 4) iron yoke 5) eddy current cup 6) shaft of the magnet 7) support of

the magnet 8) temperature compensation 9) permanent magnet 10) torsion spring

Proximity Sensors

Schematic diagram of a proximity sensor

Output current of a proximity switch versus distance

Inductive Flowmeters

)( Btimessdot= υqF

EqF sdot=BE times=υ

)(ds Btimes== υEU )(ds Btimes== υEU

)( Bd timessdot= υU

Bsdotsdotsdot= υdKU

Development of magnetic phase detection

sensor for steam generator tube

Dirac Son1 Kwan-Sang Ryu2 Duck-Gun Park3

1Hannam University Daejeon Rep of Korea2Korea Research Institute of Standards and Science Daejeon Rep of Korea3KoreaAtomic Energy Research Institute Daejeon Rep of Korea

Introduction

The layout of pressurized water reactor (PWR) components

Primary side Secondary side (non-radioactive side)(radioactive side)

The Structure of SG(Steam Generator)(degradation mechanism)

Secondary SidePrimary Side

SCC

A B

A-B

Steam outlet

Anti-vibration

SCC

Fretting

Wall thinning

IGA

U-bend

In commercial power plants SG- height up to 21 m - weight up to 800 tons - 2~4 sets of SG were installed - SG can contain from 3000 to

16000 tubes each about 20 mmin diameter

Primary coolant outlet Primary coolant inlet

Anti-vibrationbars

Tubesupportplate

Tubesheet

IGA

SCC

Pitting

SCC

Inside Tubesheet

Top of Tubesheet

by SSHwang of KAERI

Denting

Sludge pile

in diameter

The SGT is made of nickel basedInconel alloy which is composed of 75 Ni 165Cr and 815Fe

-Degradation mechanism corrosion pitting denting inter granular attack

-Inspection Eddy current Testing(ECT)

Permeability Variation Clusters (PVC)

(Ferro-magnetic phase)

-005

000

005

010

015

m (emug)

1-1

-002

000

002

004

006

008

m (emug)

1-2

-1000 -500 0 500 1000

-015

-010

-005

H ( Am )

-1000 -500 0 500 1000

-006

-004

-002

H ( Am )

The hystresis loop in the fragment of PVC parts of Kori-1 retired SG tube

-004

-002

000

002

004

006

M (emug)

Inconel 600 tested at RT

under tensile stress

1 2 3

4 5 6

7 8 9-004

-002

000

002

004

006

M(emug)

Inconel 600 Heat treated at

602 oC under tensile stress

1 2 3

How can we detect magnetic phase

(PVC)selectively from the flaws in SGT

-3000 -2000 -1000 0 1000 2000 3000

-006

H (Oe)

7 8 9

10 11 12

-3000 -2000 -1000 0 1000 2000 3000

-006

-004

H(Oe)

4 5 6

7 8 9

The hysteresis loop of the tensile tested specimen at room temperature (a) and tensile tested at high temperature (b)

The magnetic phase can be created under the high temperature andpressure conditions which is correspond to the stress corrosion crackingin the SG tube in the NPP(Bruemmer SM Charlot LA amp Henager CH (1988) Corrosion 782)

Principle of ECT

If we can separate magnetic phase selectively from the

flaws using magnetic sensor the reliability of EC in SGT

inspection will be greatly enhanced

Structure of the permeability

sensor

Dimension and photograph of U-shape

sensing yoke

Design of Magnetic Sensor for PVC

sensor sensing yoke

Photograph of the completed sensor front side (above) and rear side (bottom)

R11R12

R10

R8

R6

R9

R13

R7

R14

C18

1 n

C17

C20

C21

D2

DIODE

SIN COS

-

+

U-2A

4

13

2

-

+

U-2B

75

6

8

-

+

U-3A

13

2

8

+5VC19

104

+5V

Schematic diagram of the sensor system

Electronic Circuit of Magnetic Sensor

R20

R

R21

R

-

+

U5AD797

3

26

74

U6

D1

S12

GND3

+VCC4VCC5

IN6

-VCC7

S28

C41

R13

R26

R18

R25

R2210 Ω

R16

R14

R17

10 k

R15

R27

R32

R28

R33

R29

R34

5 k

R30

C29

C37

104

C32473

C39473C40

104

C33

104

C21

104C23

104

C25

104

C26

104

C30

104

C31

104

C35

104

C36

104

C27

104

C28

104

C34

104

C38

104

D3

DIODE

L1

1

2

L2

1

2

L3

1

2

4

-

+

U-4A

4

13

2

-

+

U-4B

75

6

8

-

+

U-5A

4

13

2

-

+

U-5B

75

6

8

-

+

U-6A

4

13

2

-

+

U-6B

75

6

8

C22

104

-5V

+5V

+5V

+5V

+5V

+5V

+5V

U7

D1

S12

GND3

+VCC4

VCC5

IN6

-VCC7

S28

+5V

-5V

-5V

-5V

-5V

-5V

-5V

-5V

-5V

R19

R24

R

R23

R

C24

OUT(X)

OUT(Y)

R1

20 kR210 k

R3

20 kR410 k

C1

104

C8

104

REF43

OUT(X)

OUT(Y)

REF43

U2

+Vcc1

CH02

CH13

CH24

CH35

COMM6

SHDN7

Vref8

+Vcc9

GND10

GND11

DOUT12BUSY13DIN14CS15

DIN16

-

+

U-1A

13

2

8

-

+

U-1B

4

75

6

C410 uF

C5104

DOUT

C210uF

C6104

C3104

DCLK

C7104

DIN

C10

01uF

CS

BUSY

C14 10uF

J1

CON6

123456

D1

DIODE

R5

47K

C9

10uF

C1310uF

Y1

OSC

OUT3

GND2

VCC4

U3

RSTVPP1

GND10

VCC20

XTAL15

XTAL24

P10AIN012P11AIN113P1214P1315P1416P1517P1618P1719

P30RXD2

P31TXD3

P32INT06

P33INT17

P34T08

P35T19

P3711

U4

C1+1

C1-3

C2+4

C2-5

VCC16

GND15

V+2

V-6

R1OUT12

R2OUT9

T1IN11

T2IN10

R1IN13

R2IN8

T1OUT14

T2OUT7

C12 10uF

C16

01uF

C15 10uF

C11

01uF

-5V

+5V

+5V

+5V

+5V

+5V

+5V

+5V

RST

OSC

OSC

RST

DCLKCSDINBUSYDOUT

U1

IN2

GND

4

OUT6

TEMP3

TRIM5

-5V

+5V

Electronic circuit diagram of the magnetic sensor

Photograph of the completed measuring system data acquisition

software in PC and probe scanning system

Experimental Setup for Magnetic Sensor

Reference material Scanning System Software LabVIEW

Reference Material (1) Normal defects and PVCs

Longitudinal and transverse defects

Def W L D Remarks

1 02 500 0213 (20 ) Inner defects

2 02 500 0427 (40 )

3 02 500 0213 (20 )Outer defectsPVC(1018)4 02 500 0427 (40 )

5 02 500 0639 (60 )

6 02 500 0852 (80 )

7 02 500 0639 (60 ) Inner defects

8 02 500 0852 (80 )

- 1 and 2 are inner defects

- 345 and 6 are outer defects with PVC

- 7 and 8 are inner defects

PVC

PVC

Defect Defect

For longitudinal defects and PVC For circumferential defects and PVC

ECT is very difficult to detect circumferential defects

We can distinguish PVCs and defects and longitudinal and circumferential defects

Flux-gate Magnetometer

One core sensor Two core sensor

3-축 flux-gate Magnetometer의 계략도

Sensorpia Co

pro

cess

or(

AV

R)

Sensor 1

RS422

Interface

Mic

ro-p

roce

ssor(

AV

R)

Sensor 2

Sensor 3

Interface

조립된 마그네토미터의 사진

Sensorpia Co

Analog PCB

Digital PCB

Sensorpia Co선형도(linearity)

10

20

30

40

50

60

y-axis

Magnetometer Output (microT)

-60 -50 -40 -30 -20 -10 0 10 20 30 40 50 60

-60

-50

-40

-30

-20

-10

0

10

Y-axis y=099946 x+0015STD 106E-4

Magnetometer Output (

Applied Magnetic Field (microT)

마그네토미터의 noise 특성 Sensorpia Co

1

10

100

y-axis

Magnetometer noise (nT)

0 1 2 3 4 5 6

1E-4

1E-3

001

01

Magnetometer noise (nT)

Frequency (Hz)

Magnetometer for KoDSAT

-150 -100 -50 0 50 100 150

-15

-10

-5

0

5

10

15

Magnetic Moment (Am

2)

Current (mA)

After Thermal Cycle Test

Measured

Resistance 193 ohm

Photograph of Magnetic torquer

Photograph of KoDSAT

Photograph of

3-axis Fluxgate

Magnetometer

Photograph of Magnetic torquer

Application of magnetometer

Moon magnetic fieldmeasurement

Telescope with direction indication

Joule Effect (Magnetostriction)

ϕ2cosel

l=

∆

0=∆

+∆

+∆

b

b

a

a

l

l

Actuator using Terfenol-D

00

05

10

B (T)

800

1000

1200

1400

1600

Magnetostriction (ppm)

-100 -50 0 50 100

-10

-05

00

B (T)

H (kAm)

2 MPa

4 MPa

6 MPa

8 MPa

10 MPa

12 MPa

-100 -50 0 50 100

-200

0

200

400

600

Magnetostriction (ppm)

H (kAm)

2 MPa

4 MPa

6 MPa

8 MPa

10 MPa

12 MPa

600

700

800

900

1000

-4 -3 -2 -1 0 1 2 3 4

0

10

20

30

40

50

60

Displacement (m

icro meter)

I (A)

FIELD

9 kAm

12 kAm

16 kAm

20 kAm

24 kAm

38 kAm

-50 -40 -30 -20 -10 0 10 20 30 40 50

-100

0

100

200

300

400

500

L (PPM)

H (kAm)

9 kAm

12 kAm

16 kAm

20 kAm

24 kAm

38 kAm

Magnetostrictive displacement sensor

Hysteresis loops under

tensile stress σ

(a) Crystalline 68 NiFe

λs = +25 10-6

(b) crystalline pure Ni λs

= -35 10-6

Villari Effect ( Inverse of Joule Effect)

= -35 10-6

(c) amorphous Co-based

alloy

λs = -35 10-6

ϕσλ 2sin2

3sdotsdot= smeE

γ

Permeability depending on the stress

σλmicromicro

1

3

2

Y

J

so

s

r =

γ

Calculated magnetization curves under stress

Variation of magnetization curve by an applied

tensile force (Co-based amorphous alloy)

Alloy Requirement

Materials for magnetoelastic sensors

Why amorphous magnetic materials are important

Stress-strain curves of several materials

Coercivity and hardness of several materials

Principles of magnetoelastic sensors

Non-contact torque sensor

Principle of cross torductor torque

sensor and flux pattern of sensor

poles on the surface of a shaft

a) without and b)with torsional load

Equivalent magnetic circuit of

cross type torque sensor

Helices of principal tensile and compressive stress on the surface of

a shaft subjected to torsion [32] Correlated changes of permeability

are detected by four-branch yoke system with sensing coils 123

and 4 and a common excitation pole

Examples of torque sensors

Four-branch type torque sensor

heads Pole structures realized

by commercial multi-pole

ferrites 14 and 18 min in

diameter (diameter of sensor

h e a d 1 7 a n d 2 4 m m

respectively) respectively)

Principle of Ring Torductor torque transducer

(a b) Physical structure (c) evolution of the

shaft surface under the transducer poles A and BRing torductor for measuring

torque on ship propeller shafts

(shaft diameter ca 500 mm)

(Courtesy ASEA Brown

Boveri AG)

Principal designs of coaxial torque sensors

Schematic diagram of data processing

electronics of a torque sensor

Extensometer (a) Construction of strain sensing element using

amorphous ribbon wound core (b) configuration of lumped

windings

∆E effect of an amorphous FeNi-based

alloy (Fe40 Ni38 Mo4 B18) Hs saturation

field

Magnetically tunable delay line

Torque Sensors using Amorphous wire

Sixtus tonk효과(large Barkhausen효과)

Hysteresis loops of a Wiegand wire for different reset fields

Curie 온도 및Hopkinson효과

Relation between normalised

saturation polarisation and

normalised Curie temperature

Permeability of a Mn-Zn ferrite as

a function of temperature and field

strength

Conclusions

1) Magnetic sensor 는 자동차 공장자동화 항공우주 및 군사용으로많이 사용되고 있다

2) 새로운 소재개발은 자기센서의 성능개발에 직접적인 영향을 준다2) 새로운 소재개발은 자기센서의 성능개발에 직접적인 영향을 준다

3) 센서의 개발을 위해서는 다양한 전공지식이 요구된다

(물리학 재료공학 기계공학 전자공학)

4) 센서분야가 고부가가치를 창출하는 부품사업이다

5) 핵심부품을 생산하는 중소기업의 item으로도 적절하다

Linear Variable Differential Transformer

AC-Excited Sensors for Linear Movement

Principle of construction of an LVDT

Electrical circuit of an LVDT

tIMtNU dd dd sdotminus=sdotminus= φ

tIMtIMUUU dd dd 1212 sdotminussdot=minus=

tIMMU dd)( 12 sdotminus=

)(12 xMMMM =minus=

tIxMU dd)( sdot= tI

UxM

dd)( =

Signal Conditioning

power supply

carrier gen

autoampcontrol

LVDTcarrieramp

demod-ulator

phase

shifter

power supply

carrier gen

passivedemod-ulator

LVDTDCamp

Block diagram of a carrier amplifier system

Block diagram of a DC amplifier system

Variable Inductive Sensors

Principle of construction

of the VLP sensor

Principle of a bridge

circuit

lANL r 20 sdotsdotsdot= micromicro

21 BA UUU minus=

21)i(ii( 211 minus+sdot= LLLUU BA ωωω

)21))()((( minus∆minus+∆+∆+sdot= LLLLLLUU BA

)212)(( minus∆+sdot= LLLUU )212)(( minus∆+sdot= LLLUU BA

LLUU BA 21 ∆sdotsdot=

llLL ∆sdot=∆ d d

llLLUU BA ∆sdotsdot= d d)2(1

Applications and Properties

Principle of a construction of a force transducer

(courtesy Hottinger Baldwin Messtechnik)

Vibrationacceleration sensor

Signal Conditioning

Schematic electrical diagram of a force transducer connected with an

amplifier (courtesy Hottinger Baldwin Messtechnik GmbH)

Variable Gap Sensors

)( FeFe2

0 LLllANL micromicromicro +sdotsdot=

FeFe2

0max lANL sdotsdotsdot= micromicro

Construction of a variable gap sensor

Characteristic of a variable gap sensor

Construction of a differential

cross-anchor sensor

Output voltage U versus core

position x plusmn a limits of the

linear rage

Applications of differential cross-anchor sensors

AC-excited Sensors for Rotary Movements

Principle of construction of a synchro

α cos10 sdotsdot= UKU y

)120-( cos10 degsdotsdot= αUKU z

)240-( cos10 degsdotsdot= αUKU x

)120-( sin3100 degsdotsdotsdot=minus= αKUUUU yxyx

)240-( sin3100 degsdotsdotsdot=minus= αKUUUU zyzy

α sin3100 sdotsdotsdot=minus= KUUUU xzxz

Application to the Torque Sensor

Principle of construction of a torque-type synchro

Torque versus angular

difference

)( sin~ rt αα minussdotKM

)( cos~ rt1r αα minussdotUU

Principle of construction of a control-type sensor

Output voltage versus

angular difference

Principle of construction of a differential sychro

Eddy Current Sensors

tBE dd curl minus=JH = curl

0 div =BH(H)B sdot= micro

E(E)J sdot= σ

A B curl= A B curl=

tdd- A E =

)dd( tAJ minus= σ

tdd curl curl AA σmicro minus=

AA) σωmicro iminus= curl )(curl(1

AA) σωmicro i=∆)((1

Eddy Current Tachometer

Construction of a speedometer (courtesy VDO Adolf Schinding AG) 1) spindle 2) bearing

3) holding spring 4) iron yoke 5) eddy current cup 6) shaft of the magnet 7) support of

the magnet 8) temperature compensation 9) permanent magnet 10) torsion spring

Proximity Sensors

Schematic diagram of a proximity sensor

Output current of a proximity switch versus distance

Inductive Flowmeters

)( Btimessdot= υqF

EqF sdot=BE times=υ

)(ds Btimes== υEU )(ds Btimes== υEU

)( Bd timessdot= υU

Bsdotsdotsdot= υdKU

Development of magnetic phase detection

sensor for steam generator tube

Dirac Son1 Kwan-Sang Ryu2 Duck-Gun Park3

1Hannam University Daejeon Rep of Korea2Korea Research Institute of Standards and Science Daejeon Rep of Korea3KoreaAtomic Energy Research Institute Daejeon Rep of Korea

Introduction

The layout of pressurized water reactor (PWR) components

Primary side Secondary side (non-radioactive side)(radioactive side)

The Structure of SG(Steam Generator)(degradation mechanism)

Secondary SidePrimary Side

SCC

A B

A-B

Steam outlet

Anti-vibration

SCC

Fretting

Wall thinning

IGA

U-bend

In commercial power plants SG- height up to 21 m - weight up to 800 tons - 2~4 sets of SG were installed - SG can contain from 3000 to

16000 tubes each about 20 mmin diameter

Primary coolant outlet Primary coolant inlet

Anti-vibrationbars

Tubesupportplate

Tubesheet

IGA

SCC

Pitting

SCC

Inside Tubesheet

Top of Tubesheet

by SSHwang of KAERI

Denting

Sludge pile

in diameter

The SGT is made of nickel basedInconel alloy which is composed of 75 Ni 165Cr and 815Fe

-Degradation mechanism corrosion pitting denting inter granular attack

-Inspection Eddy current Testing(ECT)

Permeability Variation Clusters (PVC)

(Ferro-magnetic phase)

-005

000

005

010

015

m (emug)

1-1

-002

000

002

004

006

008

m (emug)

1-2

-1000 -500 0 500 1000

-015

-010

-005

H ( Am )

-1000 -500 0 500 1000

-006

-004

-002

H ( Am )

The hystresis loop in the fragment of PVC parts of Kori-1 retired SG tube

-004

-002

000

002

004

006

M (emug)

Inconel 600 tested at RT

under tensile stress

1 2 3

4 5 6

7 8 9-004

-002

000

002

004

006

M(emug)

Inconel 600 Heat treated at

602 oC under tensile stress

1 2 3

How can we detect magnetic phase

(PVC)selectively from the flaws in SGT

-3000 -2000 -1000 0 1000 2000 3000

-006

H (Oe)

7 8 9

10 11 12

-3000 -2000 -1000 0 1000 2000 3000

-006

-004

H(Oe)

4 5 6

7 8 9

The hysteresis loop of the tensile tested specimen at room temperature (a) and tensile tested at high temperature (b)

The magnetic phase can be created under the high temperature andpressure conditions which is correspond to the stress corrosion crackingin the SG tube in the NPP(Bruemmer SM Charlot LA amp Henager CH (1988) Corrosion 782)

Principle of ECT

If we can separate magnetic phase selectively from the

flaws using magnetic sensor the reliability of EC in SGT

inspection will be greatly enhanced

Structure of the permeability

sensor

Dimension and photograph of U-shape

sensing yoke

Design of Magnetic Sensor for PVC

sensor sensing yoke

Photograph of the completed sensor front side (above) and rear side (bottom)

R11R12

R10

R8

R6

R9

R13

R7

R14

C18

1 n

C17

C20

C21

D2

DIODE

SIN COS

-

+

U-2A

4

13

2

-

+

U-2B

75

6

8

-

+

U-3A

13

2

8

+5VC19

104

+5V

Schematic diagram of the sensor system

Electronic Circuit of Magnetic Sensor

R20

R

R21

R

-

+

U5AD797

3

26

74

U6

D1

S12

GND3

+VCC4VCC5

IN6

-VCC7

S28

C41

R13

R26

R18

R25

R2210 Ω

R16

R14

R17

10 k

R15

R27

R32

R28

R33

R29

R34

5 k

R30

C29

C37

104

C32473

C39473C40

104

C33

104

C21

104C23

104

C25

104

C26

104

C30

104

C31

104

C35

104

C36

104

C27

104

C28

104

C34

104

C38

104

D3

DIODE

L1

1

2

L2

1

2

L3

1

2

4

-

+

U-4A

4

13

2

-

+

U-4B

75

6

8

-

+

U-5A

4

13

2

-

+

U-5B

75

6

8

-

+

U-6A

4

13

2

-

+

U-6B

75

6

8

C22

104

-5V

+5V

+5V

+5V

+5V

+5V

+5V

U7

D1

S12

GND3

+VCC4

VCC5

IN6

-VCC7

S28

+5V

-5V

-5V

-5V

-5V

-5V

-5V

-5V

-5V

R19

R24

R

R23

R

C24

OUT(X)

OUT(Y)

R1

20 kR210 k

R3

20 kR410 k

C1

104

C8

104

REF43

OUT(X)

OUT(Y)

REF43

U2

+Vcc1

CH02

CH13

CH24

CH35

COMM6

SHDN7

Vref8

+Vcc9

GND10

GND11

DOUT12BUSY13DIN14CS15

DIN16

-

+

U-1A

13

2

8

-

+

U-1B

4

75

6

C410 uF

C5104

DOUT

C210uF

C6104

C3104

DCLK

C7104

DIN

C10

01uF

CS

BUSY

C14 10uF

J1

CON6

123456

D1

DIODE

R5

47K

C9

10uF

C1310uF

Y1

OSC

OUT3

GND2

VCC4

U3

RSTVPP1

GND10

VCC20

XTAL15

XTAL24

P10AIN012P11AIN113P1214P1315P1416P1517P1618P1719

P30RXD2

P31TXD3

P32INT06

P33INT17

P34T08

P35T19

P3711

U4

C1+1

C1-3

C2+4

C2-5

VCC16

GND15

V+2

V-6

R1OUT12

R2OUT9

T1IN11

T2IN10

R1IN13

R2IN8

T1OUT14

T2OUT7

C12 10uF

C16

01uF

C15 10uF

C11

01uF

-5V

+5V

+5V

+5V

+5V

+5V

+5V

+5V

RST

OSC

OSC

RST

DCLKCSDINBUSYDOUT

U1

IN2

GND

4

OUT6

TEMP3

TRIM5

-5V

+5V

Electronic circuit diagram of the magnetic sensor

Photograph of the completed measuring system data acquisition

software in PC and probe scanning system

Experimental Setup for Magnetic Sensor

Reference material Scanning System Software LabVIEW

Reference Material (1) Normal defects and PVCs

Longitudinal and transverse defects

Def W L D Remarks

1 02 500 0213 (20 ) Inner defects

2 02 500 0427 (40 )

3 02 500 0213 (20 )Outer defectsPVC(1018)4 02 500 0427 (40 )

5 02 500 0639 (60 )

6 02 500 0852 (80 )

7 02 500 0639 (60 ) Inner defects

8 02 500 0852 (80 )

- 1 and 2 are inner defects

- 345 and 6 are outer defects with PVC

- 7 and 8 are inner defects

PVC

PVC

Defect Defect

For longitudinal defects and PVC For circumferential defects and PVC

ECT is very difficult to detect circumferential defects

We can distinguish PVCs and defects and longitudinal and circumferential defects

Flux-gate Magnetometer

One core sensor Two core sensor

3-축 flux-gate Magnetometer의 계략도

Sensorpia Co

pro

cess

or(

AV

R)

Sensor 1

RS422

Interface

Mic

ro-p

roce

ssor(

AV

R)

Sensor 2

Sensor 3

Interface

조립된 마그네토미터의 사진

Sensorpia Co

Analog PCB

Digital PCB

Sensorpia Co선형도(linearity)

10

20

30

40

50

60

y-axis

Magnetometer Output (microT)

-60 -50 -40 -30 -20 -10 0 10 20 30 40 50 60

-60

-50

-40

-30

-20

-10

0

10

Y-axis y=099946 x+0015STD 106E-4

Magnetometer Output (

Applied Magnetic Field (microT)

마그네토미터의 noise 특성 Sensorpia Co

1

10

100

y-axis

Magnetometer noise (nT)

0 1 2 3 4 5 6

1E-4

1E-3

001

01

Magnetometer noise (nT)

Frequency (Hz)

Magnetometer for KoDSAT

-150 -100 -50 0 50 100 150

-15

-10

-5

0

5

10

15

Magnetic Moment (Am

2)

Current (mA)

After Thermal Cycle Test

Measured

Resistance 193 ohm

Photograph of Magnetic torquer

Photograph of KoDSAT

Photograph of

3-axis Fluxgate

Magnetometer

Photograph of Magnetic torquer

Application of magnetometer

Moon magnetic fieldmeasurement

Telescope with direction indication

Joule Effect (Magnetostriction)

ϕ2cosel

l=

∆

0=∆

+∆

+∆

b

b

a

a

l

l

Actuator using Terfenol-D

00

05

10

B (T)

800

1000

1200

1400

1600

Magnetostriction (ppm)

-100 -50 0 50 100

-10

-05

00

B (T)

H (kAm)

2 MPa

4 MPa

6 MPa

8 MPa

10 MPa

12 MPa

-100 -50 0 50 100

-200

0

200

400

600

Magnetostriction (ppm)

H (kAm)

2 MPa

4 MPa

6 MPa

8 MPa

10 MPa

12 MPa

600

700

800

900

1000

-4 -3 -2 -1 0 1 2 3 4

0

10

20

30

40

50

60

Displacement (m

icro meter)

I (A)

FIELD

9 kAm

12 kAm

16 kAm

20 kAm

24 kAm

38 kAm

-50 -40 -30 -20 -10 0 10 20 30 40 50

-100

0

100

200

300

400

500

L (PPM)

H (kAm)

9 kAm

12 kAm

16 kAm

20 kAm

24 kAm

38 kAm

Magnetostrictive displacement sensor

Hysteresis loops under

tensile stress σ

(a) Crystalline 68 NiFe

λs = +25 10-6

(b) crystalline pure Ni λs

= -35 10-6

Villari Effect ( Inverse of Joule Effect)

= -35 10-6

(c) amorphous Co-based

alloy

λs = -35 10-6

ϕσλ 2sin2

3sdotsdot= smeE

γ

Permeability depending on the stress

σλmicromicro

1

3

2

Y

J

so

s

r =

γ

Calculated magnetization curves under stress

Variation of magnetization curve by an applied

tensile force (Co-based amorphous alloy)

Alloy Requirement

Materials for magnetoelastic sensors

Why amorphous magnetic materials are important

Stress-strain curves of several materials

Coercivity and hardness of several materials

Principles of magnetoelastic sensors

Non-contact torque sensor

Principle of cross torductor torque

sensor and flux pattern of sensor

poles on the surface of a shaft

a) without and b)with torsional load

Equivalent magnetic circuit of

cross type torque sensor

Helices of principal tensile and compressive stress on the surface of

a shaft subjected to torsion [32] Correlated changes of permeability

are detected by four-branch yoke system with sensing coils 123

and 4 and a common excitation pole

Examples of torque sensors

Four-branch type torque sensor

heads Pole structures realized

by commercial multi-pole

ferrites 14 and 18 min in

diameter (diameter of sensor

h e a d 1 7 a n d 2 4 m m

respectively) respectively)

Principle of Ring Torductor torque transducer

(a b) Physical structure (c) evolution of the

shaft surface under the transducer poles A and BRing torductor for measuring

torque on ship propeller shafts

(shaft diameter ca 500 mm)

(Courtesy ASEA Brown

Boveri AG)

Principal designs of coaxial torque sensors

Schematic diagram of data processing

electronics of a torque sensor

Extensometer (a) Construction of strain sensing element using

amorphous ribbon wound core (b) configuration of lumped

windings

∆E effect of an amorphous FeNi-based

alloy (Fe40 Ni38 Mo4 B18) Hs saturation

field

Magnetically tunable delay line

Torque Sensors using Amorphous wire

Sixtus tonk효과(large Barkhausen효과)

Hysteresis loops of a Wiegand wire for different reset fields

Curie 온도 및Hopkinson효과

Relation between normalised

saturation polarisation and

normalised Curie temperature

Permeability of a Mn-Zn ferrite as

a function of temperature and field

strength

Conclusions

1) Magnetic sensor 는 자동차 공장자동화 항공우주 및 군사용으로많이 사용되고 있다

2) 새로운 소재개발은 자기센서의 성능개발에 직접적인 영향을 준다2) 새로운 소재개발은 자기센서의 성능개발에 직접적인 영향을 준다

3) 센서의 개발을 위해서는 다양한 전공지식이 요구된다

(물리학 재료공학 기계공학 전자공학)

4) 센서분야가 고부가가치를 창출하는 부품사업이다

5) 핵심부품을 생산하는 중소기업의 item으로도 적절하다

Electrical circuit of an LVDT

tIMtNU dd dd sdotminus=sdotminus= φ

tIMtIMUUU dd dd 1212 sdotminussdot=minus=

tIMMU dd)( 12 sdotminus=

)(12 xMMMM =minus=

tIxMU dd)( sdot= tI

UxM

dd)( =

Signal Conditioning

power supply

carrier gen

autoampcontrol

LVDTcarrieramp

demod-ulator

phase

shifter

power supply

carrier gen

passivedemod-ulator

LVDTDCamp

Block diagram of a carrier amplifier system

Block diagram of a DC amplifier system

Variable Inductive Sensors

Principle of construction

of the VLP sensor

Principle of a bridge

circuit

lANL r 20 sdotsdotsdot= micromicro

21 BA UUU minus=

21)i(ii( 211 minus+sdot= LLLUU BA ωωω

)21))()((( minus∆minus+∆+∆+sdot= LLLLLLUU BA

)212)(( minus∆+sdot= LLLUU )212)(( minus∆+sdot= LLLUU BA

LLUU BA 21 ∆sdotsdot=

llLL ∆sdot=∆ d d

llLLUU BA ∆sdotsdot= d d)2(1

Applications and Properties

Principle of a construction of a force transducer

(courtesy Hottinger Baldwin Messtechnik)

Vibrationacceleration sensor

Signal Conditioning

Schematic electrical diagram of a force transducer connected with an

amplifier (courtesy Hottinger Baldwin Messtechnik GmbH)

Variable Gap Sensors

)( FeFe2

0 LLllANL micromicromicro +sdotsdot=

FeFe2

0max lANL sdotsdotsdot= micromicro

Construction of a variable gap sensor

Characteristic of a variable gap sensor

Construction of a differential

cross-anchor sensor

Output voltage U versus core

position x plusmn a limits of the

linear rage

Applications of differential cross-anchor sensors

AC-excited Sensors for Rotary Movements

Principle of construction of a synchro

α cos10 sdotsdot= UKU y

)120-( cos10 degsdotsdot= αUKU z

)240-( cos10 degsdotsdot= αUKU x

)120-( sin3100 degsdotsdotsdot=minus= αKUUUU yxyx

)240-( sin3100 degsdotsdotsdot=minus= αKUUUU zyzy

α sin3100 sdotsdotsdot=minus= KUUUU xzxz

Application to the Torque Sensor

Principle of construction of a torque-type synchro

Torque versus angular

difference

)( sin~ rt αα minussdotKM

)( cos~ rt1r αα minussdotUU

Principle of construction of a control-type sensor

Output voltage versus

angular difference

Principle of construction of a differential sychro

Eddy Current Sensors

tBE dd curl minus=JH = curl

0 div =BH(H)B sdot= micro

E(E)J sdot= σ

A B curl= A B curl=

tdd- A E =

)dd( tAJ minus= σ

tdd curl curl AA σmicro minus=

AA) σωmicro iminus= curl )(curl(1

AA) σωmicro i=∆)((1

Eddy Current Tachometer

Construction of a speedometer (courtesy VDO Adolf Schinding AG) 1) spindle 2) bearing

3) holding spring 4) iron yoke 5) eddy current cup 6) shaft of the magnet 7) support of

the magnet 8) temperature compensation 9) permanent magnet 10) torsion spring

Proximity Sensors

Schematic diagram of a proximity sensor

Output current of a proximity switch versus distance

Inductive Flowmeters

)( Btimessdot= υqF

EqF sdot=BE times=υ

)(ds Btimes== υEU )(ds Btimes== υEU

)( Bd timessdot= υU

Bsdotsdotsdot= υdKU

Development of magnetic phase detection

sensor for steam generator tube

Dirac Son1 Kwan-Sang Ryu2 Duck-Gun Park3

1Hannam University Daejeon Rep of Korea2Korea Research Institute of Standards and Science Daejeon Rep of Korea3KoreaAtomic Energy Research Institute Daejeon Rep of Korea

Introduction

The layout of pressurized water reactor (PWR) components

Primary side Secondary side (non-radioactive side)(radioactive side)

The Structure of SG(Steam Generator)(degradation mechanism)

Secondary SidePrimary Side

SCC

A B

A-B

Steam outlet

Anti-vibration

SCC

Fretting

Wall thinning

IGA

U-bend

In commercial power plants SG- height up to 21 m - weight up to 800 tons - 2~4 sets of SG were installed - SG can contain from 3000 to

16000 tubes each about 20 mmin diameter

Primary coolant outlet Primary coolant inlet

Anti-vibrationbars

Tubesupportplate

Tubesheet

IGA

SCC

Pitting

SCC

Inside Tubesheet

Top of Tubesheet

by SSHwang of KAERI

Denting

Sludge pile

in diameter

The SGT is made of nickel basedInconel alloy which is composed of 75 Ni 165Cr and 815Fe

-Degradation mechanism corrosion pitting denting inter granular attack

-Inspection Eddy current Testing(ECT)

Permeability Variation Clusters (PVC)

(Ferro-magnetic phase)

-005

000

005

010

015

m (emug)

1-1

-002

000

002

004

006

008

m (emug)

1-2

-1000 -500 0 500 1000

-015

-010

-005

H ( Am )

-1000 -500 0 500 1000

-006

-004

-002

H ( Am )

The hystresis loop in the fragment of PVC parts of Kori-1 retired SG tube

-004

-002

000

002

004

006

M (emug)

Inconel 600 tested at RT

under tensile stress

1 2 3

4 5 6

7 8 9-004

-002

000

002

004

006

M(emug)

Inconel 600 Heat treated at

602 oC under tensile stress

1 2 3

How can we detect magnetic phase

(PVC)selectively from the flaws in SGT

-3000 -2000 -1000 0 1000 2000 3000

-006

H (Oe)

7 8 9

10 11 12

-3000 -2000 -1000 0 1000 2000 3000

-006

-004

H(Oe)

4 5 6

7 8 9

The hysteresis loop of the tensile tested specimen at room temperature (a) and tensile tested at high temperature (b)

The magnetic phase can be created under the high temperature andpressure conditions which is correspond to the stress corrosion crackingin the SG tube in the NPP(Bruemmer SM Charlot LA amp Henager CH (1988) Corrosion 782)

Principle of ECT

If we can separate magnetic phase selectively from the

flaws using magnetic sensor the reliability of EC in SGT

inspection will be greatly enhanced

Structure of the permeability

sensor

Dimension and photograph of U-shape

sensing yoke

Design of Magnetic Sensor for PVC

sensor sensing yoke

Photograph of the completed sensor front side (above) and rear side (bottom)

R11R12

R10

R8

R6

R9

R13

R7

R14

C18

1 n

C17

C20

C21

D2

DIODE

SIN COS

-

+

U-2A

4

13

2

-

+

U-2B

75

6

8

-

+

U-3A

13

2

8

+5VC19

104

+5V

Schematic diagram of the sensor system

Electronic Circuit of Magnetic Sensor

R20

R

R21

R

-

+

U5AD797

3

26

74

U6

D1

S12

GND3

+VCC4VCC5

IN6

-VCC7

S28

C41

R13

R26

R18

R25

R2210 Ω

R16

R14

R17

10 k

R15

R27

R32

R28

R33

R29

R34

5 k

R30

C29

C37

104

C32473

C39473C40

104

C33

104

C21

104C23

104

C25

104

C26

104

C30

104

C31

104

C35

104

C36

104

C27

104

C28

104

C34

104

C38

104

D3

DIODE

L1

1

2

L2

1

2

L3

1

2

4

-

+

U-4A

4

13

2

-

+

U-4B

75

6

8

-

+

U-5A

4

13

2

-

+

U-5B

75

6

8

-

+

U-6A

4

13

2

-

+

U-6B

75

6

8

C22

104

-5V

+5V

+5V

+5V

+5V

+5V

+5V

U7

D1

S12

GND3

+VCC4

VCC5

IN6

-VCC7

S28

+5V

-5V

-5V

-5V

-5V

-5V

-5V

-5V

-5V

R19

R24

R

R23

R

C24

OUT(X)

OUT(Y)

R1

20 kR210 k

R3

20 kR410 k

C1

104

C8

104

REF43

OUT(X)

OUT(Y)

REF43

U2

+Vcc1

CH02

CH13

CH24

CH35

COMM6

SHDN7

Vref8

+Vcc9

GND10

GND11

DOUT12BUSY13DIN14CS15

DIN16

-

+

U-1A

13

2

8

-

+

U-1B

4

75

6

C410 uF

C5104

DOUT

C210uF

C6104

C3104

DCLK

C7104

DIN

C10

01uF

CS

BUSY

C14 10uF

J1

CON6

123456

D1

DIODE

R5

47K

C9

10uF

C1310uF

Y1

OSC

OUT3

GND2

VCC4

U3

RSTVPP1

GND10

VCC20

XTAL15

XTAL24

P10AIN012P11AIN113P1214P1315P1416P1517P1618P1719

P30RXD2

P31TXD3

P32INT06

P33INT17

P34T08

P35T19

P3711

U4

C1+1

C1-3

C2+4

C2-5

VCC16

GND15

V+2

V-6

R1OUT12

R2OUT9

T1IN11

T2IN10

R1IN13

R2IN8

T1OUT14

T2OUT7

C12 10uF

C16

01uF

C15 10uF

C11

01uF

-5V

+5V

+5V

+5V

+5V

+5V

+5V

+5V

RST

OSC

OSC

RST

DCLKCSDINBUSYDOUT

U1

IN2

GND

4

OUT6

TEMP3

TRIM5

-5V

+5V

Electronic circuit diagram of the magnetic sensor

Photograph of the completed measuring system data acquisition

software in PC and probe scanning system

Experimental Setup for Magnetic Sensor

Reference material Scanning System Software LabVIEW

Reference Material (1) Normal defects and PVCs

Longitudinal and transverse defects

Def W L D Remarks

1 02 500 0213 (20 ) Inner defects

2 02 500 0427 (40 )

3 02 500 0213 (20 )Outer defectsPVC(1018)4 02 500 0427 (40 )

5 02 500 0639 (60 )

6 02 500 0852 (80 )

7 02 500 0639 (60 ) Inner defects

8 02 500 0852 (80 )

- 1 and 2 are inner defects

- 345 and 6 are outer defects with PVC

- 7 and 8 are inner defects

PVC

PVC

Defect Defect

For longitudinal defects and PVC For circumferential defects and PVC

ECT is very difficult to detect circumferential defects

We can distinguish PVCs and defects and longitudinal and circumferential defects

Flux-gate Magnetometer

One core sensor Two core sensor

3-축 flux-gate Magnetometer의 계략도

Sensorpia Co

pro

cess

or(

AV

R)

Sensor 1

RS422

Interface

Mic

ro-p

roce

ssor(

AV

R)

Sensor 2

Sensor 3

Interface

조립된 마그네토미터의 사진

Sensorpia Co

Analog PCB

Digital PCB

Sensorpia Co선형도(linearity)

10

20

30

40

50

60

y-axis

Magnetometer Output (microT)

-60 -50 -40 -30 -20 -10 0 10 20 30 40 50 60

-60

-50

-40

-30

-20

-10

0

10

Y-axis y=099946 x+0015STD 106E-4

Magnetometer Output (

Applied Magnetic Field (microT)

마그네토미터의 noise 특성 Sensorpia Co

1

10

100

y-axis

Magnetometer noise (nT)

0 1 2 3 4 5 6

1E-4

1E-3

001

01

Magnetometer noise (nT)

Frequency (Hz)

Magnetometer for KoDSAT

-150 -100 -50 0 50 100 150

-15

-10

-5

0

5

10

15

Magnetic Moment (Am

2)

Current (mA)

After Thermal Cycle Test

Measured

Resistance 193 ohm

Photograph of Magnetic torquer

Photograph of KoDSAT

Photograph of

3-axis Fluxgate

Magnetometer

Photograph of Magnetic torquer

Application of magnetometer

Moon magnetic fieldmeasurement

Telescope with direction indication

Joule Effect (Magnetostriction)

ϕ2cosel

l=

∆

0=∆

+∆

+∆

b

b

a

a

l

l

Actuator using Terfenol-D

00

05

10

B (T)

800

1000

1200

1400

1600

Magnetostriction (ppm)

-100 -50 0 50 100

-10

-05

00

B (T)

H (kAm)

2 MPa

4 MPa

6 MPa

8 MPa

10 MPa

12 MPa

-100 -50 0 50 100

-200

0

200

400

600

Magnetostriction (ppm)

H (kAm)

2 MPa

4 MPa

6 MPa

8 MPa

10 MPa

12 MPa

600

700

800

900

1000

-4 -3 -2 -1 0 1 2 3 4

0

10

20

30

40

50

60

Displacement (m

icro meter)

I (A)

FIELD

9 kAm

12 kAm

16 kAm

20 kAm

24 kAm

38 kAm

-50 -40 -30 -20 -10 0 10 20 30 40 50

-100

0

100

200

300

400

500

L (PPM)

H (kAm)

9 kAm

12 kAm

16 kAm

20 kAm

24 kAm

38 kAm

Magnetostrictive displacement sensor

Hysteresis loops under

tensile stress σ

(a) Crystalline 68 NiFe

λs = +25 10-6

(b) crystalline pure Ni λs

= -35 10-6

Villari Effect ( Inverse of Joule Effect)

= -35 10-6

(c) amorphous Co-based

alloy

λs = -35 10-6

ϕσλ 2sin2

3sdotsdot= smeE

γ

Permeability depending on the stress

σλmicromicro

1

3

2

Y

J

so

s

r =

γ

Calculated magnetization curves under stress

Variation of magnetization curve by an applied

tensile force (Co-based amorphous alloy)

Alloy Requirement

Materials for magnetoelastic sensors

Why amorphous magnetic materials are important

Stress-strain curves of several materials

Coercivity and hardness of several materials

Principles of magnetoelastic sensors

Non-contact torque sensor

Principle of cross torductor torque

sensor and flux pattern of sensor

poles on the surface of a shaft

a) without and b)with torsional load

Equivalent magnetic circuit of

cross type torque sensor

Helices of principal tensile and compressive stress on the surface of

a shaft subjected to torsion [32] Correlated changes of permeability

are detected by four-branch yoke system with sensing coils 123

and 4 and a common excitation pole

Examples of torque sensors

Four-branch type torque sensor

heads Pole structures realized

by commercial multi-pole

ferrites 14 and 18 min in

diameter (diameter of sensor

h e a d 1 7 a n d 2 4 m m

respectively) respectively)

Principle of Ring Torductor torque transducer

(a b) Physical structure (c) evolution of the

shaft surface under the transducer poles A and BRing torductor for measuring

torque on ship propeller shafts

(shaft diameter ca 500 mm)

(Courtesy ASEA Brown

Boveri AG)

Principal designs of coaxial torque sensors

Schematic diagram of data processing

electronics of a torque sensor

Extensometer (a) Construction of strain sensing element using

amorphous ribbon wound core (b) configuration of lumped

windings

∆E effect of an amorphous FeNi-based

alloy (Fe40 Ni38 Mo4 B18) Hs saturation

field

Magnetically tunable delay line

Torque Sensors using Amorphous wire

Sixtus tonk효과(large Barkhausen효과)

Hysteresis loops of a Wiegand wire for different reset fields

Curie 온도 및Hopkinson효과

Relation between normalised

saturation polarisation and

normalised Curie temperature

Permeability of a Mn-Zn ferrite as

a function of temperature and field

strength

Conclusions

1) Magnetic sensor 는 자동차 공장자동화 항공우주 및 군사용으로많이 사용되고 있다

2) 새로운 소재개발은 자기센서의 성능개발에 직접적인 영향을 준다2) 새로운 소재개발은 자기센서의 성능개발에 직접적인 영향을 준다

3) 센서의 개발을 위해서는 다양한 전공지식이 요구된다

(물리학 재료공학 기계공학 전자공학)

4) 센서분야가 고부가가치를 창출하는 부품사업이다

5) 핵심부품을 생산하는 중소기업의 item으로도 적절하다

Signal Conditioning

power supply

carrier gen

autoampcontrol

LVDTcarrieramp

demod-ulator

phase

shifter

power supply

carrier gen

passivedemod-ulator

LVDTDCamp

Block diagram of a carrier amplifier system

Block diagram of a DC amplifier system

Variable Inductive Sensors

Principle of construction

of the VLP sensor

Principle of a bridge

circuit

lANL r 20 sdotsdotsdot= micromicro

21 BA UUU minus=

21)i(ii( 211 minus+sdot= LLLUU BA ωωω

)21))()((( minus∆minus+∆+∆+sdot= LLLLLLUU BA

)212)(( minus∆+sdot= LLLUU )212)(( minus∆+sdot= LLLUU BA

LLUU BA 21 ∆sdotsdot=

llLL ∆sdot=∆ d d

llLLUU BA ∆sdotsdot= d d)2(1

Applications and Properties

Principle of a construction of a force transducer

(courtesy Hottinger Baldwin Messtechnik)

Vibrationacceleration sensor

Signal Conditioning

Schematic electrical diagram of a force transducer connected with an

amplifier (courtesy Hottinger Baldwin Messtechnik GmbH)

Variable Gap Sensors

)( FeFe2

0 LLllANL micromicromicro +sdotsdot=

FeFe2

0max lANL sdotsdotsdot= micromicro

Construction of a variable gap sensor

Characteristic of a variable gap sensor

Construction of a differential

cross-anchor sensor

Output voltage U versus core

position x plusmn a limits of the

linear rage

Applications of differential cross-anchor sensors

AC-excited Sensors for Rotary Movements

Principle of construction of a synchro

α cos10 sdotsdot= UKU y

)120-( cos10 degsdotsdot= αUKU z

)240-( cos10 degsdotsdot= αUKU x

)120-( sin3100 degsdotsdotsdot=minus= αKUUUU yxyx

)240-( sin3100 degsdotsdotsdot=minus= αKUUUU zyzy

α sin3100 sdotsdotsdot=minus= KUUUU xzxz

Application to the Torque Sensor

Principle of construction of a torque-type synchro

Torque versus angular

difference

)( sin~ rt αα minussdotKM

)( cos~ rt1r αα minussdotUU

Principle of construction of a control-type sensor

Output voltage versus

angular difference

Principle of construction of a differential sychro

Eddy Current Sensors

tBE dd curl minus=JH = curl

0 div =BH(H)B sdot= micro

E(E)J sdot= σ

A B curl= A B curl=

tdd- A E =

)dd( tAJ minus= σ

tdd curl curl AA σmicro minus=

AA) σωmicro iminus= curl )(curl(1

AA) σωmicro i=∆)((1

Eddy Current Tachometer

Construction of a speedometer (courtesy VDO Adolf Schinding AG) 1) spindle 2) bearing

3) holding spring 4) iron yoke 5) eddy current cup 6) shaft of the magnet 7) support of

the magnet 8) temperature compensation 9) permanent magnet 10) torsion spring

Proximity Sensors

Schematic diagram of a proximity sensor

Output current of a proximity switch versus distance

Inductive Flowmeters

)( Btimessdot= υqF

EqF sdot=BE times=υ

)(ds Btimes== υEU )(ds Btimes== υEU

)( Bd timessdot= υU

Bsdotsdotsdot= υdKU

Development of magnetic phase detection

sensor for steam generator tube

Dirac Son1 Kwan-Sang Ryu2 Duck-Gun Park3

1Hannam University Daejeon Rep of Korea2Korea Research Institute of Standards and Science Daejeon Rep of Korea3KoreaAtomic Energy Research Institute Daejeon Rep of Korea

Introduction

The layout of pressurized water reactor (PWR) components

Primary side Secondary side (non-radioactive side)(radioactive side)

The Structure of SG(Steam Generator)(degradation mechanism)

Secondary SidePrimary Side

SCC

A B

A-B

Steam outlet

Anti-vibration

SCC

Fretting

Wall thinning

IGA

U-bend

In commercial power plants SG- height up to 21 m - weight up to 800 tons - 2~4 sets of SG were installed - SG can contain from 3000 to

16000 tubes each about 20 mmin diameter

Primary coolant outlet Primary coolant inlet

Anti-vibrationbars

Tubesupportplate

Tubesheet

IGA

SCC

Pitting

SCC

Inside Tubesheet

Top of Tubesheet

by SSHwang of KAERI

Denting

Sludge pile

in diameter

The SGT is made of nickel basedInconel alloy which is composed of 75 Ni 165Cr and 815Fe

-Degradation mechanism corrosion pitting denting inter granular attack

-Inspection Eddy current Testing(ECT)

Permeability Variation Clusters (PVC)

(Ferro-magnetic phase)

-005

000

005

010

015

m (emug)

1-1

-002

000

002

004

006

008

m (emug)

1-2

-1000 -500 0 500 1000

-015

-010

-005

H ( Am )

-1000 -500 0 500 1000

-006

-004

-002

H ( Am )

The hystresis loop in the fragment of PVC parts of Kori-1 retired SG tube

-004

-002

000

002

004

006

M (emug)

Inconel 600 tested at RT

under tensile stress

1 2 3

4 5 6

7 8 9-004

-002

000

002

004

006

M(emug)

Inconel 600 Heat treated at

602 oC under tensile stress

1 2 3

How can we detect magnetic phase

(PVC)selectively from the flaws in SGT

-3000 -2000 -1000 0 1000 2000 3000

-006

H (Oe)

7 8 9

10 11 12

-3000 -2000 -1000 0 1000 2000 3000

-006

-004

H(Oe)

4 5 6

7 8 9

The hysteresis loop of the tensile tested specimen at room temperature (a) and tensile tested at high temperature (b)

The magnetic phase can be created under the high temperature andpressure conditions which is correspond to the stress corrosion crackingin the SG tube in the NPP(Bruemmer SM Charlot LA amp Henager CH (1988) Corrosion 782)

Principle of ECT

If we can separate magnetic phase selectively from the

flaws using magnetic sensor the reliability of EC in SGT

inspection will be greatly enhanced

Structure of the permeability

sensor

Dimension and photograph of U-shape

sensing yoke

Design of Magnetic Sensor for PVC

sensor sensing yoke

Photograph of the completed sensor front side (above) and rear side (bottom)

R11R12

R10

R8

R6

R9

R13

R7

R14

C18

1 n

C17

C20

C21

D2

DIODE

SIN COS

-

+

U-2A

4

13

2

-

+

U-2B

75

6

8

-

+

U-3A

13

2

8

+5VC19

104

+5V

Schematic diagram of the sensor system

Electronic Circuit of Magnetic Sensor

R20

R

R21

R

-

+

U5AD797

3

26

74

U6

D1

S12

GND3

+VCC4VCC5

IN6

-VCC7

S28

C41

R13

R26

R18

R25

R2210 Ω

R16

R14

R17

10 k

R15

R27

R32

R28

R33

R29

R34

5 k

R30

C29

C37

104

C32473

C39473C40

104

C33

104

C21

104C23

104

C25

104

C26

104

C30

104

C31

104

C35

104

C36

104

C27

104

C28

104

C34

104

C38

104

D3

DIODE

L1

1

2

L2

1

2

L3

1

2

4

-

+

U-4A

4

13

2

-

+

U-4B

75

6

8

-

+

U-5A

4

13

2

-

+

U-5B

75

6

8

-

+

U-6A

4

13

2

-

+

U-6B

75

6

8

C22

104

-5V

+5V

+5V

+5V

+5V

+5V

+5V

U7

D1

S12

GND3

+VCC4

VCC5

IN6

-VCC7

S28

+5V

-5V

-5V

-5V

-5V

-5V

-5V

-5V

-5V

R19

R24

R

R23

R

C24

OUT(X)

OUT(Y)

R1

20 kR210 k

R3

20 kR410 k

C1

104

C8

104

REF43

OUT(X)

OUT(Y)

REF43

U2

+Vcc1

CH02

CH13

CH24

CH35

COMM6

SHDN7

Vref8

+Vcc9

GND10

GND11

DOUT12BUSY13DIN14CS15

DIN16

-

+

U-1A

13

2

8

-

+

U-1B

4

75

6

C410 uF

C5104

DOUT

C210uF

C6104

C3104

DCLK

C7104

DIN

C10

01uF

CS

BUSY

C14 10uF

J1

CON6

123456

D1

DIODE

R5

47K

C9

10uF

C1310uF

Y1

OSC

OUT3

GND2

VCC4

U3

RSTVPP1

GND10

VCC20

XTAL15

XTAL24

P10AIN012P11AIN113P1214P1315P1416P1517P1618P1719

P30RXD2

P31TXD3

P32INT06

P33INT17

P34T08

P35T19

P3711

U4

C1+1

C1-3

C2+4

C2-5

VCC16

GND15

V+2

V-6

R1OUT12

R2OUT9

T1IN11

T2IN10

R1IN13

R2IN8

T1OUT14

T2OUT7

C12 10uF

C16

01uF

C15 10uF

C11

01uF

-5V

+5V

+5V

+5V

+5V

+5V

+5V

+5V

RST

OSC

OSC

RST

DCLKCSDINBUSYDOUT

U1

IN2

GND

4

OUT6

TEMP3

TRIM5

-5V

+5V

Electronic circuit diagram of the magnetic sensor

Photograph of the completed measuring system data acquisition

software in PC and probe scanning system

Experimental Setup for Magnetic Sensor

Reference material Scanning System Software LabVIEW

Reference Material (1) Normal defects and PVCs

Longitudinal and transverse defects

Def W L D Remarks

1 02 500 0213 (20 ) Inner defects

2 02 500 0427 (40 )

3 02 500 0213 (20 )Outer defectsPVC(1018)4 02 500 0427 (40 )

5 02 500 0639 (60 )

6 02 500 0852 (80 )

7 02 500 0639 (60 ) Inner defects

8 02 500 0852 (80 )

- 1 and 2 are inner defects

- 345 and 6 are outer defects with PVC

- 7 and 8 are inner defects

PVC

PVC

Defect Defect

For longitudinal defects and PVC For circumferential defects and PVC

ECT is very difficult to detect circumferential defects

We can distinguish PVCs and defects and longitudinal and circumferential defects

Flux-gate Magnetometer

One core sensor Two core sensor

3-축 flux-gate Magnetometer의 계략도

Sensorpia Co

pro

cess

or(

AV

R)

Sensor 1

RS422

Interface

Mic

ro-p

roce

ssor(

AV

R)

Sensor 2

Sensor 3

Interface

조립된 마그네토미터의 사진

Sensorpia Co

Analog PCB

Digital PCB

Sensorpia Co선형도(linearity)

10

20

30

40

50

60

y-axis

Magnetometer Output (microT)

-60 -50 -40 -30 -20 -10 0 10 20 30 40 50 60

-60

-50

-40

-30

-20

-10

0

10

Y-axis y=099946 x+0015STD 106E-4

Magnetometer Output (

Applied Magnetic Field (microT)

마그네토미터의 noise 특성 Sensorpia Co

1

10

100

y-axis

Magnetometer noise (nT)

0 1 2 3 4 5 6

1E-4

1E-3

001

01

Magnetometer noise (nT)

Frequency (Hz)

Magnetometer for KoDSAT

-150 -100 -50 0 50 100 150

-15

-10

-5

0

5

10

15

Magnetic Moment (Am

2)

Current (mA)

After Thermal Cycle Test

Measured

Resistance 193 ohm

Photograph of Magnetic torquer

Photograph of KoDSAT

Photograph of

3-axis Fluxgate

Magnetometer

Photograph of Magnetic torquer

Application of magnetometer

Moon magnetic fieldmeasurement

Telescope with direction indication

Joule Effect (Magnetostriction)

ϕ2cosel

l=

∆

0=∆

+∆

+∆

b

b

a

a

l

l

Actuator using Terfenol-D

00

05

10

B (T)

800

1000

1200

1400

1600

Magnetostriction (ppm)

-100 -50 0 50 100

-10

-05

00

B (T)

H (kAm)

2 MPa

4 MPa

6 MPa

8 MPa

10 MPa

12 MPa

-100 -50 0 50 100

-200

0

200

400

600

Magnetostriction (ppm)

H (kAm)

2 MPa

4 MPa

6 MPa

8 MPa

10 MPa

12 MPa

600

700

800

900

1000

-4 -3 -2 -1 0 1 2 3 4

0

10

20

30

40

50

60

Displacement (m

icro meter)

I (A)

FIELD

9 kAm

12 kAm

16 kAm

20 kAm

24 kAm

38 kAm

-50 -40 -30 -20 -10 0 10 20 30 40 50

-100

0

100

200

300

400

500

L (PPM)

H (kAm)

9 kAm

12 kAm

16 kAm

20 kAm

24 kAm

38 kAm

Magnetostrictive displacement sensor

Hysteresis loops under

tensile stress σ

(a) Crystalline 68 NiFe

λs = +25 10-6

(b) crystalline pure Ni λs

= -35 10-6

Villari Effect ( Inverse of Joule Effect)

= -35 10-6

(c) amorphous Co-based

alloy

λs = -35 10-6

ϕσλ 2sin2

3sdotsdot= smeE

γ

Permeability depending on the stress

σλmicromicro

1

3

2

Y

J

so

s

r =

γ

Calculated magnetization curves under stress

Variation of magnetization curve by an applied

tensile force (Co-based amorphous alloy)

Alloy Requirement

Materials for magnetoelastic sensors

Why amorphous magnetic materials are important

Stress-strain curves of several materials

Coercivity and hardness of several materials

Principles of magnetoelastic sensors

Non-contact torque sensor

Principle of cross torductor torque

sensor and flux pattern of sensor

poles on the surface of a shaft

a) without and b)with torsional load

Equivalent magnetic circuit of

cross type torque sensor

Helices of principal tensile and compressive stress on the surface of

a shaft subjected to torsion [32] Correlated changes of permeability

are detected by four-branch yoke system with sensing coils 123

and 4 and a common excitation pole

Examples of torque sensors

Four-branch type torque sensor

heads Pole structures realized

by commercial multi-pole

ferrites 14 and 18 min in

diameter (diameter of sensor

h e a d 1 7 a n d 2 4 m m

respectively) respectively)

Principle of Ring Torductor torque transducer

(a b) Physical structure (c) evolution of the

shaft surface under the transducer poles A and BRing torductor for measuring

torque on ship propeller shafts

(shaft diameter ca 500 mm)

(Courtesy ASEA Brown

Boveri AG)

Principal designs of coaxial torque sensors

Schematic diagram of data processing

electronics of a torque sensor

Extensometer (a) Construction of strain sensing element using

amorphous ribbon wound core (b) configuration of lumped

windings

∆E effect of an amorphous FeNi-based

alloy (Fe40 Ni38 Mo4 B18) Hs saturation

field

Magnetically tunable delay line

Torque Sensors using Amorphous wire

Sixtus tonk효과(large Barkhausen효과)

Hysteresis loops of a Wiegand wire for different reset fields

Curie 온도 및Hopkinson효과

Relation between normalised

saturation polarisation and

normalised Curie temperature

Permeability of a Mn-Zn ferrite as

a function of temperature and field

strength

Conclusions

1) Magnetic sensor 는 자동차 공장자동화 항공우주 및 군사용으로많이 사용되고 있다

2) 새로운 소재개발은 자기센서의 성능개발에 직접적인 영향을 준다2) 새로운 소재개발은 자기센서의 성능개발에 직접적인 영향을 준다

3) 센서의 개발을 위해서는 다양한 전공지식이 요구된다

(물리학 재료공학 기계공학 전자공학)

4) 센서분야가 고부가가치를 창출하는 부품사업이다

5) 핵심부품을 생산하는 중소기업의 item으로도 적절하다

Variable Inductive Sensors

Principle of construction

of the VLP sensor

Principle of a bridge

circuit

lANL r 20 sdotsdotsdot= micromicro

21 BA UUU minus=

21)i(ii( 211 minus+sdot= LLLUU BA ωωω

)21))()((( minus∆minus+∆+∆+sdot= LLLLLLUU BA

)212)(( minus∆+sdot= LLLUU )212)(( minus∆+sdot= LLLUU BA

LLUU BA 21 ∆sdotsdot=

llLL ∆sdot=∆ d d

llLLUU BA ∆sdotsdot= d d)2(1

Applications and Properties

Principle of a construction of a force transducer

(courtesy Hottinger Baldwin Messtechnik)

Vibrationacceleration sensor

Signal Conditioning

Schematic electrical diagram of a force transducer connected with an

amplifier (courtesy Hottinger Baldwin Messtechnik GmbH)

Variable Gap Sensors

)( FeFe2

0 LLllANL micromicromicro +sdotsdot=

FeFe2

0max lANL sdotsdotsdot= micromicro

Construction of a variable gap sensor

Characteristic of a variable gap sensor

Construction of a differential

cross-anchor sensor

Output voltage U versus core

position x plusmn a limits of the

linear rage

Applications of differential cross-anchor sensors

AC-excited Sensors for Rotary Movements

Principle of construction of a synchro

α cos10 sdotsdot= UKU y

)120-( cos10 degsdotsdot= αUKU z

)240-( cos10 degsdotsdot= αUKU x

)120-( sin3100 degsdotsdotsdot=minus= αKUUUU yxyx

)240-( sin3100 degsdotsdotsdot=minus= αKUUUU zyzy

α sin3100 sdotsdotsdot=minus= KUUUU xzxz

Application to the Torque Sensor

Principle of construction of a torque-type synchro

Torque versus angular

difference

)( sin~ rt αα minussdotKM

)( cos~ rt1r αα minussdotUU

Principle of construction of a control-type sensor

Output voltage versus

angular difference

Principle of construction of a differential sychro

Eddy Current Sensors

tBE dd curl minus=JH = curl

0 div =BH(H)B sdot= micro

E(E)J sdot= σ

A B curl= A B curl=

tdd- A E =

)dd( tAJ minus= σ

tdd curl curl AA σmicro minus=

AA) σωmicro iminus= curl )(curl(1

AA) σωmicro i=∆)((1

Eddy Current Tachometer

Construction of a speedometer (courtesy VDO Adolf Schinding AG) 1) spindle 2) bearing

3) holding spring 4) iron yoke 5) eddy current cup 6) shaft of the magnet 7) support of

the magnet 8) temperature compensation 9) permanent magnet 10) torsion spring

Proximity Sensors

Schematic diagram of a proximity sensor

Output current of a proximity switch versus distance

Inductive Flowmeters

)( Btimessdot= υqF

EqF sdot=BE times=υ

)(ds Btimes== υEU )(ds Btimes== υEU

)( Bd timessdot= υU

Bsdotsdotsdot= υdKU

Development of magnetic phase detection

sensor for steam generator tube

Dirac Son1 Kwan-Sang Ryu2 Duck-Gun Park3

1Hannam University Daejeon Rep of Korea2Korea Research Institute of Standards and Science Daejeon Rep of Korea3KoreaAtomic Energy Research Institute Daejeon Rep of Korea

Introduction

The layout of pressurized water reactor (PWR) components

Primary side Secondary side (non-radioactive side)(radioactive side)

The Structure of SG(Steam Generator)(degradation mechanism)

Secondary SidePrimary Side

SCC

A B

A-B

Steam outlet

Anti-vibration

SCC

Fretting

Wall thinning

IGA

U-bend

In commercial power plants SG- height up to 21 m - weight up to 800 tons - 2~4 sets of SG were installed - SG can contain from 3000 to

16000 tubes each about 20 mmin diameter

Primary coolant outlet Primary coolant inlet

Anti-vibrationbars

Tubesupportplate

Tubesheet

IGA

SCC

Pitting

SCC

Inside Tubesheet

Top of Tubesheet

by SSHwang of KAERI

Denting

Sludge pile

in diameter

The SGT is made of nickel basedInconel alloy which is composed of 75 Ni 165Cr and 815Fe

-Degradation mechanism corrosion pitting denting inter granular attack

-Inspection Eddy current Testing(ECT)

Permeability Variation Clusters (PVC)

(Ferro-magnetic phase)

-005

000

005

010

015

m (emug)

1-1

-002

000

002

004

006

008

m (emug)

1-2

-1000 -500 0 500 1000

-015

-010

-005

H ( Am )

-1000 -500 0 500 1000

-006

-004

-002

H ( Am )

The hystresis loop in the fragment of PVC parts of Kori-1 retired SG tube

-004

-002

000

002

004

006

M (emug)

Inconel 600 tested at RT

under tensile stress

1 2 3

4 5 6

7 8 9-004

-002

000

002

004

006

M(emug)

Inconel 600 Heat treated at

602 oC under tensile stress

1 2 3

How can we detect magnetic phase

(PVC)selectively from the flaws in SGT

-3000 -2000 -1000 0 1000 2000 3000

-006

H (Oe)

7 8 9

10 11 12

-3000 -2000 -1000 0 1000 2000 3000

-006

-004

H(Oe)

4 5 6

7 8 9

The hysteresis loop of the tensile tested specimen at room temperature (a) and tensile tested at high temperature (b)

The magnetic phase can be created under the high temperature andpressure conditions which is correspond to the stress corrosion crackingin the SG tube in the NPP(Bruemmer SM Charlot LA amp Henager CH (1988) Corrosion 782)

Principle of ECT

If we can separate magnetic phase selectively from the

flaws using magnetic sensor the reliability of EC in SGT

inspection will be greatly enhanced

Structure of the permeability

sensor

Dimension and photograph of U-shape

sensing yoke

Design of Magnetic Sensor for PVC

sensor sensing yoke

Photograph of the completed sensor front side (above) and rear side (bottom)

R11R12

R10

R8

R6

R9

R13

R7

R14

C18

1 n

C17

C20

C21

D2

DIODE

SIN COS

-

+

U-2A

4

13

2

-

+

U-2B

75

6

8

-

+

U-3A

13

2

8

+5VC19

104

+5V

Schematic diagram of the sensor system

Electronic Circuit of Magnetic Sensor

R20

R

R21

R

-

+

U5AD797

3

26

74

U6

D1

S12

GND3

+VCC4VCC5

IN6

-VCC7

S28

C41

R13

R26

R18

R25

R2210 Ω

R16

R14

R17

10 k

R15

R27

R32

R28

R33

R29

R34

5 k

R30

C29

C37

104

C32473

C39473C40

104

C33

104

C21

104C23

104

C25

104

C26

104

C30

104

C31

104

C35

104

C36

104

C27

104

C28

104

C34

104

C38

104

D3

DIODE

L1

1

2

L2

1

2

L3

1

2

4

-

+

U-4A

4

13

2

-

+

U-4B

75

6

8

-

+

U-5A

4

13

2

-

+

U-5B

75

6

8

-

+

U-6A

4

13

2

-

+

U-6B

75

6

8

C22

104

-5V

+5V

+5V

+5V

+5V

+5V

+5V

U7

D1

S12

GND3

+VCC4

VCC5

IN6

-VCC7

S28

+5V

-5V

-5V

-5V

-5V

-5V

-5V

-5V

-5V

R19

R24

R

R23

R

C24

OUT(X)

OUT(Y)

R1

20 kR210 k

R3

20 kR410 k

C1

104

C8

104

REF43

OUT(X)

OUT(Y)

REF43

U2

+Vcc1

CH02

CH13

CH24

CH35

COMM6

SHDN7

Vref8

+Vcc9

GND10

GND11

DOUT12BUSY13DIN14CS15

DIN16

-

+

U-1A

13

2

8

-

+

U-1B

4

75

6

C410 uF

C5104

DOUT

C210uF

C6104

C3104

DCLK

C7104

DIN

C10

01uF

CS

BUSY

C14 10uF

J1

CON6

123456

D1

DIODE

R5

47K

C9

10uF

C1310uF

Y1

OSC

OUT3

GND2

VCC4

U3

RSTVPP1

GND10

VCC20

XTAL15

XTAL24

P10AIN012P11AIN113P1214P1315P1416P1517P1618P1719

P30RXD2

P31TXD3

P32INT06

P33INT17

P34T08

P35T19

P3711

U4

C1+1

C1-3

C2+4

C2-5

VCC16

GND15

V+2

V-6

R1OUT12

R2OUT9

T1IN11

T2IN10

R1IN13

R2IN8

T1OUT14

T2OUT7

C12 10uF

C16

01uF

C15 10uF

C11

01uF

-5V

+5V

+5V

+5V

+5V

+5V

+5V

+5V

RST

OSC

OSC

RST

DCLKCSDINBUSYDOUT

U1

IN2

GND

4

OUT6

TEMP3

TRIM5

-5V

+5V

Electronic circuit diagram of the magnetic sensor

Photograph of the completed measuring system data acquisition

software in PC and probe scanning system

Experimental Setup for Magnetic Sensor

Reference material Scanning System Software LabVIEW

Reference Material (1) Normal defects and PVCs

Longitudinal and transverse defects

Def W L D Remarks

1 02 500 0213 (20 ) Inner defects

2 02 500 0427 (40 )

3 02 500 0213 (20 )Outer defectsPVC(1018)4 02 500 0427 (40 )

5 02 500 0639 (60 )

6 02 500 0852 (80 )

7 02 500 0639 (60 ) Inner defects

8 02 500 0852 (80 )

- 1 and 2 are inner defects

- 345 and 6 are outer defects with PVC

- 7 and 8 are inner defects

PVC

PVC

Defect Defect

For longitudinal defects and PVC For circumferential defects and PVC

ECT is very difficult to detect circumferential defects

We can distinguish PVCs and defects and longitudinal and circumferential defects

Flux-gate Magnetometer

One core sensor Two core sensor

3-축 flux-gate Magnetometer의 계략도

Sensorpia Co

pro

cess

or(

AV

R)

Sensor 1

RS422

Interface

Mic

ro-p

roce

ssor(

AV

R)

Sensor 2

Sensor 3

Interface

조립된 마그네토미터의 사진

Sensorpia Co

Analog PCB

Digital PCB

Sensorpia Co선형도(linearity)

10

20

30

40

50

60

y-axis

Magnetometer Output (microT)

-60 -50 -40 -30 -20 -10 0 10 20 30 40 50 60

-60

-50

-40

-30

-20

-10

0

10

Y-axis y=099946 x+0015STD 106E-4

Magnetometer Output (

Applied Magnetic Field (microT)

마그네토미터의 noise 특성 Sensorpia Co

1

10

100

y-axis

Magnetometer noise (nT)

0 1 2 3 4 5 6

1E-4

1E-3

001

01

Magnetometer noise (nT)

Frequency (Hz)

Magnetometer for KoDSAT

-150 -100 -50 0 50 100 150

-15

-10

-5

0

5

10

15

Magnetic Moment (Am

2)

Current (mA)

After Thermal Cycle Test

Measured

Resistance 193 ohm

Photograph of Magnetic torquer

Photograph of KoDSAT

Photograph of

3-axis Fluxgate

Magnetometer

Photograph of Magnetic torquer

Application of magnetometer

Moon magnetic fieldmeasurement

Telescope with direction indication

Joule Effect (Magnetostriction)

ϕ2cosel

l=

∆

0=∆

+∆

+∆

b

b

a

a

l

l

Actuator using Terfenol-D

00

05

10

B (T)

800

1000

1200

1400

1600

Magnetostriction (ppm)

-100 -50 0 50 100

-10

-05

00

B (T)

H (kAm)

2 MPa

4 MPa

6 MPa

8 MPa

10 MPa

12 MPa

-100 -50 0 50 100

-200

0

200

400

600

Magnetostriction (ppm)

H (kAm)

2 MPa

4 MPa

6 MPa

8 MPa

10 MPa

12 MPa

600

700

800

900

1000

-4 -3 -2 -1 0 1 2 3 4

0

10

20

30

40

50

60

Displacement (m

icro meter)

I (A)

FIELD

9 kAm

12 kAm

16 kAm

20 kAm

24 kAm

38 kAm

-50 -40 -30 -20 -10 0 10 20 30 40 50

-100

0

100

200

300

400

500

L (PPM)

H (kAm)

9 kAm

12 kAm

16 kAm

20 kAm

24 kAm

38 kAm

Magnetostrictive displacement sensor

Hysteresis loops under

tensile stress σ

(a) Crystalline 68 NiFe

λs = +25 10-6

(b) crystalline pure Ni λs

= -35 10-6

Villari Effect ( Inverse of Joule Effect)

= -35 10-6

(c) amorphous Co-based

alloy

λs = -35 10-6

ϕσλ 2sin2

3sdotsdot= smeE

γ

Permeability depending on the stress

σλmicromicro

1

3

2

Y

J

so

s

r =

γ

Calculated magnetization curves under stress

Variation of magnetization curve by an applied

tensile force (Co-based amorphous alloy)

Alloy Requirement

Materials for magnetoelastic sensors

Why amorphous magnetic materials are important

Stress-strain curves of several materials

Coercivity and hardness of several materials

Principles of magnetoelastic sensors

Non-contact torque sensor

Principle of cross torductor torque

sensor and flux pattern of sensor

poles on the surface of a shaft

a) without and b)with torsional load

Equivalent magnetic circuit of

cross type torque sensor

Helices of principal tensile and compressive stress on the surface of

a shaft subjected to torsion [32] Correlated changes of permeability

are detected by four-branch yoke system with sensing coils 123

and 4 and a common excitation pole

Examples of torque sensors

Four-branch type torque sensor

heads Pole structures realized

by commercial multi-pole

ferrites 14 and 18 min in

diameter (diameter of sensor

h e a d 1 7 a n d 2 4 m m

respectively) respectively)

Principle of Ring Torductor torque transducer

(a b) Physical structure (c) evolution of the

shaft surface under the transducer poles A and BRing torductor for measuring

torque on ship propeller shafts

(shaft diameter ca 500 mm)

(Courtesy ASEA Brown

Boveri AG)

Principal designs of coaxial torque sensors

Schematic diagram of data processing

electronics of a torque sensor

Extensometer (a) Construction of strain sensing element using

amorphous ribbon wound core (b) configuration of lumped

windings

∆E effect of an amorphous FeNi-based

alloy (Fe40 Ni38 Mo4 B18) Hs saturation

field

Magnetically tunable delay line

Torque Sensors using Amorphous wire

Sixtus tonk효과(large Barkhausen효과)

Hysteresis loops of a Wiegand wire for different reset fields

Curie 온도 및Hopkinson효과

Relation between normalised

saturation polarisation and

normalised Curie temperature

Permeability of a Mn-Zn ferrite as

a function of temperature and field

strength

Conclusions

1) Magnetic sensor 는 자동차 공장자동화 항공우주 및 군사용으로많이 사용되고 있다

2) 새로운 소재개발은 자기센서의 성능개발에 직접적인 영향을 준다2) 새로운 소재개발은 자기센서의 성능개발에 직접적인 영향을 준다

3) 센서의 개발을 위해서는 다양한 전공지식이 요구된다

(물리학 재료공학 기계공학 전자공학)

4) 센서분야가 고부가가치를 창출하는 부품사업이다

5) 핵심부품을 생산하는 중소기업의 item으로도 적절하다

lANL r 20 sdotsdotsdot= micromicro

21 BA UUU minus=

21)i(ii( 211 minus+sdot= LLLUU BA ωωω

)21))()((( minus∆minus+∆+∆+sdot= LLLLLLUU BA

)212)(( minus∆+sdot= LLLUU )212)(( minus∆+sdot= LLLUU BA

LLUU BA 21 ∆sdotsdot=

llLL ∆sdot=∆ d d

llLLUU BA ∆sdotsdot= d d)2(1

Applications and Properties

Principle of a construction of a force transducer

(courtesy Hottinger Baldwin Messtechnik)

Vibrationacceleration sensor

Signal Conditioning

Schematic electrical diagram of a force transducer connected with an

amplifier (courtesy Hottinger Baldwin Messtechnik GmbH)

Variable Gap Sensors

)( FeFe2

0 LLllANL micromicromicro +sdotsdot=

FeFe2

0max lANL sdotsdotsdot= micromicro

Construction of a variable gap sensor

Characteristic of a variable gap sensor

Construction of a differential

cross-anchor sensor

Output voltage U versus core

position x plusmn a limits of the

linear rage

Applications of differential cross-anchor sensors

AC-excited Sensors for Rotary Movements

Principle of construction of a synchro

α cos10 sdotsdot= UKU y

)120-( cos10 degsdotsdot= αUKU z

)240-( cos10 degsdotsdot= αUKU x

)120-( sin3100 degsdotsdotsdot=minus= αKUUUU yxyx

)240-( sin3100 degsdotsdotsdot=minus= αKUUUU zyzy

α sin3100 sdotsdotsdot=minus= KUUUU xzxz

Application to the Torque Sensor

Principle of construction of a torque-type synchro

Torque versus angular

difference

)( sin~ rt αα minussdotKM

)( cos~ rt1r αα minussdotUU

Principle of construction of a control-type sensor

Output voltage versus

angular difference

Principle of construction of a differential sychro

Eddy Current Sensors

tBE dd curl minus=JH = curl

0 div =BH(H)B sdot= micro

E(E)J sdot= σ

A B curl= A B curl=

tdd- A E =

)dd( tAJ minus= σ

tdd curl curl AA σmicro minus=

AA) σωmicro iminus= curl )(curl(1

AA) σωmicro i=∆)((1

Eddy Current Tachometer

Construction of a speedometer (courtesy VDO Adolf Schinding AG) 1) spindle 2) bearing

3) holding spring 4) iron yoke 5) eddy current cup 6) shaft of the magnet 7) support of

the magnet 8) temperature compensation 9) permanent magnet 10) torsion spring

Proximity Sensors

Schematic diagram of a proximity sensor

Output current of a proximity switch versus distance

Inductive Flowmeters

)( Btimessdot= υqF

EqF sdot=BE times=υ

)(ds Btimes== υEU )(ds Btimes== υEU

)( Bd timessdot= υU

Bsdotsdotsdot= υdKU

Development of magnetic phase detection

sensor for steam generator tube

Dirac Son1 Kwan-Sang Ryu2 Duck-Gun Park3

1Hannam University Daejeon Rep of Korea2Korea Research Institute of Standards and Science Daejeon Rep of Korea3KoreaAtomic Energy Research Institute Daejeon Rep of Korea

Introduction

The layout of pressurized water reactor (PWR) components

Primary side Secondary side (non-radioactive side)(radioactive side)

The Structure of SG(Steam Generator)(degradation mechanism)

Secondary SidePrimary Side

SCC

A B

A-B

Steam outlet

Anti-vibration

SCC

Fretting

Wall thinning

IGA

U-bend

In commercial power plants SG- height up to 21 m - weight up to 800 tons - 2~4 sets of SG were installed - SG can contain from 3000 to

16000 tubes each about 20 mmin diameter

Primary coolant outlet Primary coolant inlet

Anti-vibrationbars

Tubesupportplate

Tubesheet

IGA

SCC

Pitting

SCC

Inside Tubesheet

Top of Tubesheet

by SSHwang of KAERI

Denting

Sludge pile

in diameter

The SGT is made of nickel basedInconel alloy which is composed of 75 Ni 165Cr and 815Fe

-Degradation mechanism corrosion pitting denting inter granular attack

-Inspection Eddy current Testing(ECT)

Permeability Variation Clusters (PVC)

(Ferro-magnetic phase)

-005

000

005

010

015

m (emug)

1-1

-002

000

002

004

006

008

m (emug)

1-2

-1000 -500 0 500 1000

-015

-010

-005

H ( Am )

-1000 -500 0 500 1000

-006

-004

-002

H ( Am )

The hystresis loop in the fragment of PVC parts of Kori-1 retired SG tube

-004

-002

000

002

004

006

M (emug)

Inconel 600 tested at RT

under tensile stress

1 2 3

4 5 6

7 8 9-004

-002

000

002

004

006

M(emug)

Inconel 600 Heat treated at

602 oC under tensile stress

1 2 3

How can we detect magnetic phase

(PVC)selectively from the flaws in SGT

-3000 -2000 -1000 0 1000 2000 3000

-006

H (Oe)

7 8 9

10 11 12

-3000 -2000 -1000 0 1000 2000 3000

-006

-004

H(Oe)

4 5 6

7 8 9

The hysteresis loop of the tensile tested specimen at room temperature (a) and tensile tested at high temperature (b)

The magnetic phase can be created under the high temperature andpressure conditions which is correspond to the stress corrosion crackingin the SG tube in the NPP(Bruemmer SM Charlot LA amp Henager CH (1988) Corrosion 782)

Principle of ECT

If we can separate magnetic phase selectively from the

flaws using magnetic sensor the reliability of EC in SGT

inspection will be greatly enhanced

Structure of the permeability

sensor

Dimension and photograph of U-shape

sensing yoke

Design of Magnetic Sensor for PVC

sensor sensing yoke

Photograph of the completed sensor front side (above) and rear side (bottom)

R11R12

R10

R8

R6

R9

R13

R7

R14

C18

1 n

C17

C20

C21

D2

DIODE

SIN COS

-

+

U-2A

4

13

2

-

+

U-2B

75

6

8

-

+

U-3A

13

2

8

+5VC19

104

+5V

Schematic diagram of the sensor system

Electronic Circuit of Magnetic Sensor

R20

R

R21

R

-

+

U5AD797

3

26

74

U6

D1

S12

GND3

+VCC4VCC5

IN6

-VCC7

S28

C41

R13

R26

R18

R25

R2210 Ω

R16

R14

R17

10 k

R15

R27

R32

R28

R33

R29

R34

5 k

R30

C29

C37

104

C32473

C39473C40

104

C33

104

C21

104C23

104

C25

104

C26

104

C30

104

C31

104

C35

104

C36

104

C27

104

C28

104

C34

104

C38

104

D3

DIODE

L1

1

2

L2

1

2

L3

1

2

4

-

+

U-4A

4

13

2

-

+

U-4B

75

6

8

-

+

U-5A

4

13

2

-

+

U-5B

75

6

8

-

+

U-6A

4

13

2

-

+

U-6B

75

6

8

C22

104

-5V

+5V

+5V

+5V

+5V

+5V

+5V

U7

D1

S12

GND3

+VCC4

VCC5

IN6

-VCC7

S28

+5V

-5V

-5V

-5V

-5V

-5V

-5V

-5V

-5V

R19

R24

R

R23

R

C24

OUT(X)

OUT(Y)

R1

20 kR210 k

R3

20 kR410 k

C1

104

C8

104

REF43

OUT(X)

OUT(Y)

REF43

U2

+Vcc1

CH02

CH13

CH24

CH35

COMM6

SHDN7

Vref8

+Vcc9

GND10

GND11

DOUT12BUSY13DIN14CS15

DIN16

-

+

U-1A

13

2

8

-

+

U-1B

4

75

6

C410 uF

C5104

DOUT

C210uF

C6104

C3104

DCLK

C7104

DIN

C10

01uF

CS

BUSY

C14 10uF

J1

CON6

123456

D1

DIODE

R5

47K

C9

10uF

C1310uF

Y1

OSC

OUT3

GND2

VCC4

U3

RSTVPP1

GND10

VCC20

XTAL15

XTAL24

P10AIN012P11AIN113P1214P1315P1416P1517P1618P1719

P30RXD2

P31TXD3

P32INT06

P33INT17

P34T08

P35T19

P3711

U4

C1+1

C1-3

C2+4

C2-5

VCC16

GND15

V+2

V-6

R1OUT12

R2OUT9

T1IN11

T2IN10

R1IN13

R2IN8

T1OUT14

T2OUT7

C12 10uF

C16

01uF

C15 10uF

C11

01uF

-5V

+5V

+5V

+5V

+5V

+5V

+5V

+5V

RST

OSC

OSC

RST

DCLKCSDINBUSYDOUT

U1

IN2

GND

4

OUT6

TEMP3

TRIM5

-5V

+5V

Electronic circuit diagram of the magnetic sensor

Photograph of the completed measuring system data acquisition

software in PC and probe scanning system

Experimental Setup for Magnetic Sensor

Reference material Scanning System Software LabVIEW

Reference Material (1) Normal defects and PVCs

Longitudinal and transverse defects

Def W L D Remarks

1 02 500 0213 (20 ) Inner defects

2 02 500 0427 (40 )

3 02 500 0213 (20 )Outer defectsPVC(1018)4 02 500 0427 (40 )

5 02 500 0639 (60 )

6 02 500 0852 (80 )

7 02 500 0639 (60 ) Inner defects

8 02 500 0852 (80 )

- 1 and 2 are inner defects

- 345 and 6 are outer defects with PVC

- 7 and 8 are inner defects

PVC

PVC

Defect Defect

For longitudinal defects and PVC For circumferential defects and PVC

ECT is very difficult to detect circumferential defects

We can distinguish PVCs and defects and longitudinal and circumferential defects

Flux-gate Magnetometer

One core sensor Two core sensor

3-축 flux-gate Magnetometer의 계략도

Sensorpia Co

pro

cess

or(

AV

R)

Sensor 1

RS422

Interface

Mic

ro-p

roce

ssor(

AV

R)

Sensor 2

Sensor 3

Interface

조립된 마그네토미터의 사진

Sensorpia Co

Analog PCB

Digital PCB

Sensorpia Co선형도(linearity)

10

20

30

40

50

60

y-axis

Magnetometer Output (microT)

-60 -50 -40 -30 -20 -10 0 10 20 30 40 50 60

-60

-50

-40

-30

-20

-10

0

10

Y-axis y=099946 x+0015STD 106E-4

Magnetometer Output (

Applied Magnetic Field (microT)

마그네토미터의 noise 특성 Sensorpia Co

1

10

100

y-axis

Magnetometer noise (nT)

0 1 2 3 4 5 6

1E-4

1E-3

001

01

Magnetometer noise (nT)

Frequency (Hz)

Magnetometer for KoDSAT

-150 -100 -50 0 50 100 150

-15

-10

-5

0

5

10

15

Magnetic Moment (Am

2)

Current (mA)

After Thermal Cycle Test

Measured

Resistance 193 ohm

Photograph of Magnetic torquer

Photograph of KoDSAT

Photograph of

3-axis Fluxgate

Magnetometer

Photograph of Magnetic torquer

Application of magnetometer

Moon magnetic fieldmeasurement

Telescope with direction indication

Joule Effect (Magnetostriction)

ϕ2cosel

l=

∆

0=∆

+∆

+∆

b

b

a

a

l

l

Actuator using Terfenol-D

00

05

10

B (T)

800

1000

1200

1400

1600

Magnetostriction (ppm)

-100 -50 0 50 100

-10

-05

00

B (T)

H (kAm)

2 MPa

4 MPa

6 MPa

8 MPa

10 MPa

12 MPa

-100 -50 0 50 100

-200

0

200

400

600

Magnetostriction (ppm)

H (kAm)

2 MPa

4 MPa

6 MPa

8 MPa

10 MPa

12 MPa

600

700

800

900

1000

-4 -3 -2 -1 0 1 2 3 4

0

10

20

30

40

50

60

Displacement (m

icro meter)

I (A)

FIELD

9 kAm

12 kAm

16 kAm

20 kAm

24 kAm

38 kAm

-50 -40 -30 -20 -10 0 10 20 30 40 50

-100

0

100

200

300

400

500

L (PPM)

H (kAm)

9 kAm

12 kAm

16 kAm

20 kAm

24 kAm

38 kAm

Magnetostrictive displacement sensor

Hysteresis loops under

tensile stress σ

(a) Crystalline 68 NiFe

λs = +25 10-6

(b) crystalline pure Ni λs

= -35 10-6

Villari Effect ( Inverse of Joule Effect)

= -35 10-6

(c) amorphous Co-based

alloy

λs = -35 10-6

ϕσλ 2sin2

3sdotsdot= smeE

γ

Permeability depending on the stress

σλmicromicro

1

3

2

Y

J

so

s

r =

γ

Calculated magnetization curves under stress

Variation of magnetization curve by an applied

tensile force (Co-based amorphous alloy)

Alloy Requirement

Materials for magnetoelastic sensors

Why amorphous magnetic materials are important

Stress-strain curves of several materials

Coercivity and hardness of several materials

Principles of magnetoelastic sensors

Non-contact torque sensor

Principle of cross torductor torque

sensor and flux pattern of sensor

poles on the surface of a shaft

a) without and b)with torsional load

Equivalent magnetic circuit of

cross type torque sensor

Helices of principal tensile and compressive stress on the surface of

a shaft subjected to torsion [32] Correlated changes of permeability

are detected by four-branch yoke system with sensing coils 123

and 4 and a common excitation pole

Examples of torque sensors

Four-branch type torque sensor

heads Pole structures realized

by commercial multi-pole

ferrites 14 and 18 min in

diameter (diameter of sensor

h e a d 1 7 a n d 2 4 m m

respectively) respectively)

Principle of Ring Torductor torque transducer

(a b) Physical structure (c) evolution of the

shaft surface under the transducer poles A and BRing torductor for measuring

torque on ship propeller shafts

(shaft diameter ca 500 mm)

(Courtesy ASEA Brown

Boveri AG)

Principal designs of coaxial torque sensors

Schematic diagram of data processing

electronics of a torque sensor

Extensometer (a) Construction of strain sensing element using

amorphous ribbon wound core (b) configuration of lumped

windings

∆E effect of an amorphous FeNi-based

alloy (Fe40 Ni38 Mo4 B18) Hs saturation

field

Magnetically tunable delay line

Torque Sensors using Amorphous wire

Sixtus tonk효과(large Barkhausen효과)

Hysteresis loops of a Wiegand wire for different reset fields

Curie 온도 및Hopkinson효과

Relation between normalised

saturation polarisation and

normalised Curie temperature

Permeability of a Mn-Zn ferrite as

a function of temperature and field

strength

Conclusions

1) Magnetic sensor 는 자동차 공장자동화 항공우주 및 군사용으로많이 사용되고 있다

2) 새로운 소재개발은 자기센서의 성능개발에 직접적인 영향을 준다2) 새로운 소재개발은 자기센서의 성능개발에 직접적인 영향을 준다

3) 센서의 개발을 위해서는 다양한 전공지식이 요구된다

(물리학 재료공학 기계공학 전자공학)

4) 센서분야가 고부가가치를 창출하는 부품사업이다

5) 핵심부품을 생산하는 중소기업의 item으로도 적절하다

Applications and Properties

Principle of a construction of a force transducer

(courtesy Hottinger Baldwin Messtechnik)

Vibrationacceleration sensor

Signal Conditioning

Schematic electrical diagram of a force transducer connected with an

amplifier (courtesy Hottinger Baldwin Messtechnik GmbH)

Variable Gap Sensors

)( FeFe2

0 LLllANL micromicromicro +sdotsdot=

FeFe2

0max lANL sdotsdotsdot= micromicro

Construction of a variable gap sensor

Characteristic of a variable gap sensor

Construction of a differential

cross-anchor sensor

Output voltage U versus core

position x plusmn a limits of the

linear rage

Applications of differential cross-anchor sensors

AC-excited Sensors for Rotary Movements

Principle of construction of a synchro

α cos10 sdotsdot= UKU y

)120-( cos10 degsdotsdot= αUKU z

)240-( cos10 degsdotsdot= αUKU x

)120-( sin3100 degsdotsdotsdot=minus= αKUUUU yxyx

)240-( sin3100 degsdotsdotsdot=minus= αKUUUU zyzy

α sin3100 sdotsdotsdot=minus= KUUUU xzxz

Application to the Torque Sensor

Principle of construction of a torque-type synchro

Torque versus angular

difference

)( sin~ rt αα minussdotKM

)( cos~ rt1r αα minussdotUU

Principle of construction of a control-type sensor

Output voltage versus

angular difference

Principle of construction of a differential sychro

Eddy Current Sensors

tBE dd curl minus=JH = curl

0 div =BH(H)B sdot= micro

E(E)J sdot= σ

A B curl= A B curl=

tdd- A E =

)dd( tAJ minus= σ

tdd curl curl AA σmicro minus=

AA) σωmicro iminus= curl )(curl(1

AA) σωmicro i=∆)((1

Eddy Current Tachometer

Construction of a speedometer (courtesy VDO Adolf Schinding AG) 1) spindle 2) bearing

3) holding spring 4) iron yoke 5) eddy current cup 6) shaft of the magnet 7) support of

the magnet 8) temperature compensation 9) permanent magnet 10) torsion spring

Proximity Sensors

Schematic diagram of a proximity sensor

Output current of a proximity switch versus distance

Inductive Flowmeters

)( Btimessdot= υqF

EqF sdot=BE times=υ

)(ds Btimes== υEU )(ds Btimes== υEU

)( Bd timessdot= υU

Bsdotsdotsdot= υdKU

Development of magnetic phase detection

sensor for steam generator tube

Dirac Son1 Kwan-Sang Ryu2 Duck-Gun Park3

1Hannam University Daejeon Rep of Korea2Korea Research Institute of Standards and Science Daejeon Rep of Korea3KoreaAtomic Energy Research Institute Daejeon Rep of Korea

Introduction

The layout of pressurized water reactor (PWR) components

Primary side Secondary side (non-radioactive side)(radioactive side)

The Structure of SG(Steam Generator)(degradation mechanism)

Secondary SidePrimary Side

SCC

A B

A-B

Steam outlet

Anti-vibration

SCC

Fretting

Wall thinning

IGA

U-bend

In commercial power plants SG- height up to 21 m - weight up to 800 tons - 2~4 sets of SG were installed - SG can contain from 3000 to

16000 tubes each about 20 mmin diameter

Primary coolant outlet Primary coolant inlet

Anti-vibrationbars

Tubesupportplate

Tubesheet

IGA

SCC

Pitting

SCC

Inside Tubesheet

Top of Tubesheet

by SSHwang of KAERI

Denting

Sludge pile

in diameter

The SGT is made of nickel basedInconel alloy which is composed of 75 Ni 165Cr and 815Fe

-Degradation mechanism corrosion pitting denting inter granular attack

-Inspection Eddy current Testing(ECT)

Permeability Variation Clusters (PVC)

(Ferro-magnetic phase)

-005

000

005

010

015

m (emug)

1-1

-002

000

002

004

006

008

m (emug)

1-2

-1000 -500 0 500 1000

-015

-010

-005

H ( Am )

-1000 -500 0 500 1000

-006

-004

-002

H ( Am )

The hystresis loop in the fragment of PVC parts of Kori-1 retired SG tube

-004

-002

000

002

004

006

M (emug)

Inconel 600 tested at RT

under tensile stress

1 2 3

4 5 6

7 8 9-004

-002

000

002

004

006

M(emug)

Inconel 600 Heat treated at

602 oC under tensile stress

1 2 3

How can we detect magnetic phase

(PVC)selectively from the flaws in SGT

-3000 -2000 -1000 0 1000 2000 3000

-006

H (Oe)

7 8 9

10 11 12

-3000 -2000 -1000 0 1000 2000 3000

-006

-004

H(Oe)

4 5 6

7 8 9

The hysteresis loop of the tensile tested specimen at room temperature (a) and tensile tested at high temperature (b)

The magnetic phase can be created under the high temperature andpressure conditions which is correspond to the stress corrosion crackingin the SG tube in the NPP(Bruemmer SM Charlot LA amp Henager CH (1988) Corrosion 782)

Principle of ECT

If we can separate magnetic phase selectively from the

flaws using magnetic sensor the reliability of EC in SGT

inspection will be greatly enhanced

Structure of the permeability

sensor

Dimension and photograph of U-shape

sensing yoke

Design of Magnetic Sensor for PVC

sensor sensing yoke

Photograph of the completed sensor front side (above) and rear side (bottom)

R11R12

R10

R8

R6

R9

R13

R7

R14

C18

1 n

C17

C20

C21

D2

DIODE

SIN COS

-

+

U-2A

4

13

2

-

+

U-2B

75

6

8

-

+

U-3A

13

2

8

+5VC19

104

+5V

Schematic diagram of the sensor system

Electronic Circuit of Magnetic Sensor

R20

R

R21

R

-

+

U5AD797

3

26

74

U6

D1

S12

GND3

+VCC4VCC5

IN6

-VCC7

S28

C41

R13

R26

R18

R25

R2210 Ω

R16

R14

R17

10 k

R15

R27

R32

R28

R33

R29

R34

5 k

R30

C29

C37

104

C32473

C39473C40

104

C33

104

C21

104C23

104

C25

104

C26

104

C30

104

C31

104

C35

104

C36

104

C27

104

C28

104

C34

104

C38

104

D3

DIODE

L1

1

2

L2

1

2

L3

1

2

4

-

+

U-4A

4

13

2

-

+

U-4B

75

6

8

-

+

U-5A

4

13

2

-

+

U-5B

75

6

8

-

+

U-6A

4

13

2

-

+

U-6B

75

6

8

C22

104

-5V

+5V

+5V

+5V

+5V

+5V

+5V

U7

D1

S12

GND3

+VCC4

VCC5

IN6

-VCC7

S28

+5V

-5V

-5V

-5V

-5V

-5V

-5V

-5V

-5V

R19

R24

R

R23

R

C24

OUT(X)

OUT(Y)

R1

20 kR210 k

R3

20 kR410 k

C1

104

C8

104

REF43

OUT(X)

OUT(Y)

REF43

U2

+Vcc1

CH02

CH13

CH24

CH35

COMM6

SHDN7

Vref8

+Vcc9

GND10

GND11

DOUT12BUSY13DIN14CS15

DIN16

-

+

U-1A

13

2

8

-

+

U-1B

4

75

6

C410 uF

C5104

DOUT

C210uF

C6104

C3104

DCLK

C7104

DIN

C10

01uF

CS

BUSY

C14 10uF

J1

CON6

123456

D1

DIODE

R5

47K

C9

10uF

C1310uF

Y1

OSC

OUT3

GND2

VCC4

U3

RSTVPP1

GND10

VCC20

XTAL15

XTAL24

P10AIN012P11AIN113P1214P1315P1416P1517P1618P1719

P30RXD2

P31TXD3

P32INT06

P33INT17

P34T08

P35T19

P3711

U4

C1+1

C1-3

C2+4

C2-5

VCC16

GND15

V+2

V-6

R1OUT12

R2OUT9

T1IN11

T2IN10

R1IN13

R2IN8

T1OUT14

T2OUT7

C12 10uF

C16

01uF

C15 10uF

C11

01uF

-5V

+5V

+5V

+5V

+5V

+5V

+5V

+5V

RST

OSC

OSC

RST

DCLKCSDINBUSYDOUT

U1

IN2

GND

4

OUT6

TEMP3

TRIM5

-5V

+5V

Electronic circuit diagram of the magnetic sensor

Photograph of the completed measuring system data acquisition

software in PC and probe scanning system

Experimental Setup for Magnetic Sensor

Reference material Scanning System Software LabVIEW

Reference Material (1) Normal defects and PVCs

Longitudinal and transverse defects

Def W L D Remarks

1 02 500 0213 (20 ) Inner defects

2 02 500 0427 (40 )

3 02 500 0213 (20 )Outer defectsPVC(1018)4 02 500 0427 (40 )

5 02 500 0639 (60 )

6 02 500 0852 (80 )

7 02 500 0639 (60 ) Inner defects

8 02 500 0852 (80 )

- 1 and 2 are inner defects

- 345 and 6 are outer defects with PVC

- 7 and 8 are inner defects

PVC

PVC

Defect Defect

For longitudinal defects and PVC For circumferential defects and PVC

ECT is very difficult to detect circumferential defects

We can distinguish PVCs and defects and longitudinal and circumferential defects

Flux-gate Magnetometer

One core sensor Two core sensor

3-축 flux-gate Magnetometer의 계략도

Sensorpia Co

pro

cess

or(

AV

R)

Sensor 1

RS422

Interface

Mic

ro-p

roce

ssor(

AV

R)

Sensor 2

Sensor 3

Interface

조립된 마그네토미터의 사진

Sensorpia Co

Analog PCB

Digital PCB

Sensorpia Co선형도(linearity)

10

20

30

40

50

60

y-axis

Magnetometer Output (microT)

-60 -50 -40 -30 -20 -10 0 10 20 30 40 50 60

-60

-50

-40

-30

-20

-10

0

10

Y-axis y=099946 x+0015STD 106E-4

Magnetometer Output (

Applied Magnetic Field (microT)

마그네토미터의 noise 특성 Sensorpia Co

1

10

100

y-axis

Magnetometer noise (nT)

0 1 2 3 4 5 6

1E-4

1E-3

001

01

Magnetometer noise (nT)

Frequency (Hz)

Magnetometer for KoDSAT

-150 -100 -50 0 50 100 150

-15

-10

-5

0

5

10

15

Magnetic Moment (Am

2)

Current (mA)

After Thermal Cycle Test

Measured

Resistance 193 ohm

Photograph of Magnetic torquer

Photograph of KoDSAT

Photograph of

3-axis Fluxgate

Magnetometer

Photograph of Magnetic torquer

Application of magnetometer

Moon magnetic fieldmeasurement

Telescope with direction indication

Joule Effect (Magnetostriction)

ϕ2cosel

l=

∆

0=∆

+∆

+∆

b

b

a

a

l

l

Actuator using Terfenol-D

00

05

10

B (T)

800

1000

1200

1400

1600

Magnetostriction (ppm)

-100 -50 0 50 100

-10

-05

00

B (T)

H (kAm)

2 MPa

4 MPa

6 MPa

8 MPa

10 MPa

12 MPa

-100 -50 0 50 100

-200

0

200

400

600

Magnetostriction (ppm)

H (kAm)

2 MPa

4 MPa

6 MPa

8 MPa

10 MPa

12 MPa

600

700

800

900

1000

-4 -3 -2 -1 0 1 2 3 4

0

10

20

30

40

50

60

Displacement (m

icro meter)

I (A)

FIELD

9 kAm

12 kAm

16 kAm

20 kAm

24 kAm

38 kAm

-50 -40 -30 -20 -10 0 10 20 30 40 50

-100

0

100

200

300

400

500

L (PPM)

H (kAm)

9 kAm

12 kAm

16 kAm

20 kAm

24 kAm

38 kAm

Magnetostrictive displacement sensor

Hysteresis loops under

tensile stress σ

(a) Crystalline 68 NiFe

λs = +25 10-6

(b) crystalline pure Ni λs

= -35 10-6

Villari Effect ( Inverse of Joule Effect)

= -35 10-6

(c) amorphous Co-based

alloy

λs = -35 10-6

ϕσλ 2sin2

3sdotsdot= smeE

γ

Permeability depending on the stress

σλmicromicro

1

3

2

Y

J

so

s

r =

γ

Calculated magnetization curves under stress

Variation of magnetization curve by an applied

tensile force (Co-based amorphous alloy)

Alloy Requirement

Materials for magnetoelastic sensors

Why amorphous magnetic materials are important

Stress-strain curves of several materials

Coercivity and hardness of several materials

Principles of magnetoelastic sensors

Non-contact torque sensor

Principle of cross torductor torque

sensor and flux pattern of sensor

poles on the surface of a shaft

a) without and b)with torsional load

Equivalent magnetic circuit of

cross type torque sensor

Helices of principal tensile and compressive stress on the surface of

a shaft subjected to torsion [32] Correlated changes of permeability

are detected by four-branch yoke system with sensing coils 123

and 4 and a common excitation pole

Examples of torque sensors

Four-branch type torque sensor

heads Pole structures realized

by commercial multi-pole

ferrites 14 and 18 min in

diameter (diameter of sensor

h e a d 1 7 a n d 2 4 m m

respectively) respectively)

Principle of Ring Torductor torque transducer

(a b) Physical structure (c) evolution of the

shaft surface under the transducer poles A and BRing torductor for measuring

torque on ship propeller shafts

(shaft diameter ca 500 mm)

(Courtesy ASEA Brown

Boveri AG)

Principal designs of coaxial torque sensors

Schematic diagram of data processing

electronics of a torque sensor

Extensometer (a) Construction of strain sensing element using

amorphous ribbon wound core (b) configuration of lumped

windings

∆E effect of an amorphous FeNi-based

alloy (Fe40 Ni38 Mo4 B18) Hs saturation

field

Magnetically tunable delay line

Torque Sensors using Amorphous wire

Sixtus tonk효과(large Barkhausen효과)

Hysteresis loops of a Wiegand wire for different reset fields

Curie 온도 및Hopkinson효과

Relation between normalised

saturation polarisation and

normalised Curie temperature

Permeability of a Mn-Zn ferrite as

a function of temperature and field

strength

Conclusions

1) Magnetic sensor 는 자동차 공장자동화 항공우주 및 군사용으로많이 사용되고 있다

2) 새로운 소재개발은 자기센서의 성능개발에 직접적인 영향을 준다2) 새로운 소재개발은 자기센서의 성능개발에 직접적인 영향을 준다

3) 센서의 개발을 위해서는 다양한 전공지식이 요구된다

(물리학 재료공학 기계공학 전자공학)

4) 센서분야가 고부가가치를 창출하는 부품사업이다

5) 핵심부품을 생산하는 중소기업의 item으로도 적절하다

Vibrationacceleration sensor

Signal Conditioning

Schematic electrical diagram of a force transducer connected with an

amplifier (courtesy Hottinger Baldwin Messtechnik GmbH)

Variable Gap Sensors

)( FeFe2

0 LLllANL micromicromicro +sdotsdot=

FeFe2

0max lANL sdotsdotsdot= micromicro

Construction of a variable gap sensor

Characteristic of a variable gap sensor

Construction of a differential

cross-anchor sensor

Output voltage U versus core

position x plusmn a limits of the

linear rage

Applications of differential cross-anchor sensors

AC-excited Sensors for Rotary Movements

Principle of construction of a synchro

α cos10 sdotsdot= UKU y

)120-( cos10 degsdotsdot= αUKU z

)240-( cos10 degsdotsdot= αUKU x

)120-( sin3100 degsdotsdotsdot=minus= αKUUUU yxyx

)240-( sin3100 degsdotsdotsdot=minus= αKUUUU zyzy

α sin3100 sdotsdotsdot=minus= KUUUU xzxz

Application to the Torque Sensor

Principle of construction of a torque-type synchro

Torque versus angular

difference

)( sin~ rt αα minussdotKM

)( cos~ rt1r αα minussdotUU

Principle of construction of a control-type sensor

Output voltage versus

angular difference

Principle of construction of a differential sychro

Eddy Current Sensors

tBE dd curl minus=JH = curl

0 div =BH(H)B sdot= micro

E(E)J sdot= σ

A B curl= A B curl=

tdd- A E =

)dd( tAJ minus= σ

tdd curl curl AA σmicro minus=

AA) σωmicro iminus= curl )(curl(1

AA) σωmicro i=∆)((1

Eddy Current Tachometer

Construction of a speedometer (courtesy VDO Adolf Schinding AG) 1) spindle 2) bearing

3) holding spring 4) iron yoke 5) eddy current cup 6) shaft of the magnet 7) support of

the magnet 8) temperature compensation 9) permanent magnet 10) torsion spring

Proximity Sensors

Schematic diagram of a proximity sensor

Output current of a proximity switch versus distance

Inductive Flowmeters

)( Btimessdot= υqF

EqF sdot=BE times=υ

)(ds Btimes== υEU )(ds Btimes== υEU

)( Bd timessdot= υU

Bsdotsdotsdot= υdKU

Development of magnetic phase detection

sensor for steam generator tube

Dirac Son1 Kwan-Sang Ryu2 Duck-Gun Park3

1Hannam University Daejeon Rep of Korea2Korea Research Institute of Standards and Science Daejeon Rep of Korea3KoreaAtomic Energy Research Institute Daejeon Rep of Korea

Introduction

The layout of pressurized water reactor (PWR) components

Primary side Secondary side (non-radioactive side)(radioactive side)

The Structure of SG(Steam Generator)(degradation mechanism)

Secondary SidePrimary Side

SCC

A B

A-B

Steam outlet

Anti-vibration

SCC

Fretting

Wall thinning

IGA

U-bend

In commercial power plants SG- height up to 21 m - weight up to 800 tons - 2~4 sets of SG were installed - SG can contain from 3000 to

16000 tubes each about 20 mmin diameter

Primary coolant outlet Primary coolant inlet

Anti-vibrationbars

Tubesupportplate

Tubesheet

IGA

SCC

Pitting

SCC

Inside Tubesheet

Top of Tubesheet

by SSHwang of KAERI

Denting

Sludge pile

in diameter

The SGT is made of nickel basedInconel alloy which is composed of 75 Ni 165Cr and 815Fe

-Degradation mechanism corrosion pitting denting inter granular attack

-Inspection Eddy current Testing(ECT)

Permeability Variation Clusters (PVC)

(Ferro-magnetic phase)

-005

000

005

010

015

m (emug)

1-1

-002

000

002

004

006

008

m (emug)

1-2

-1000 -500 0 500 1000

-015

-010

-005

H ( Am )

-1000 -500 0 500 1000

-006

-004

-002

H ( Am )

The hystresis loop in the fragment of PVC parts of Kori-1 retired SG tube

-004

-002

000

002

004

006

M (emug)

Inconel 600 tested at RT

under tensile stress

1 2 3

4 5 6

7 8 9-004

-002

000

002

004

006

M(emug)

Inconel 600 Heat treated at

602 oC under tensile stress

1 2 3

How can we detect magnetic phase

(PVC)selectively from the flaws in SGT

-3000 -2000 -1000 0 1000 2000 3000

-006

H (Oe)

7 8 9

10 11 12

-3000 -2000 -1000 0 1000 2000 3000

-006

-004

H(Oe)

4 5 6

7 8 9

The hysteresis loop of the tensile tested specimen at room temperature (a) and tensile tested at high temperature (b)

The magnetic phase can be created under the high temperature andpressure conditions which is correspond to the stress corrosion crackingin the SG tube in the NPP(Bruemmer SM Charlot LA amp Henager CH (1988) Corrosion 782)

Principle of ECT

If we can separate magnetic phase selectively from the

flaws using magnetic sensor the reliability of EC in SGT

inspection will be greatly enhanced

Structure of the permeability

sensor

Dimension and photograph of U-shape

sensing yoke

Design of Magnetic Sensor for PVC

sensor sensing yoke

Photograph of the completed sensor front side (above) and rear side (bottom)

R11R12

R10

R8

R6

R9

R13

R7

R14

C18

1 n

C17

C20

C21

D2

DIODE

SIN COS

-

+

U-2A

4

13

2

-

+

U-2B

75

6

8

-

+

U-3A

13

2

8

+5VC19

104

+5V

Schematic diagram of the sensor system

Electronic Circuit of Magnetic Sensor

R20

R

R21

R

-

+

U5AD797

3

26

74

U6

D1

S12

GND3

+VCC4VCC5

IN6

-VCC7

S28

C41

R13

R26

R18

R25

R2210 Ω

R16

R14

R17

10 k

R15

R27

R32

R28

R33

R29

R34

5 k

R30

C29

C37

104

C32473

C39473C40

104

C33

104

C21

104C23

104

C25

104

C26

104

C30

104

C31

104

C35

104

C36

104

C27

104

C28

104

C34

104

C38

104

D3

DIODE

L1

1

2

L2

1

2

L3

1

2

4

-

+

U-4A

4

13

2

-

+

U-4B

75

6

8

-

+

U-5A

4

13

2

-

+

U-5B

75

6

8

-

+

U-6A

4

13

2

-

+

U-6B

75

6

8

C22

104

-5V

+5V

+5V

+5V

+5V

+5V

+5V

U7

D1

S12

GND3

+VCC4

VCC5

IN6

-VCC7

S28

+5V

-5V

-5V

-5V

-5V

-5V

-5V

-5V

-5V

R19

R24

R

R23

R

C24

OUT(X)

OUT(Y)

R1

20 kR210 k

R3

20 kR410 k

C1

104

C8

104

REF43

OUT(X)

OUT(Y)

REF43

U2

+Vcc1

CH02

CH13

CH24

CH35

COMM6

SHDN7

Vref8

+Vcc9

GND10

GND11

DOUT12BUSY13DIN14CS15

DIN16

-

+

U-1A

13

2

8

-

+

U-1B

4

75

6

C410 uF

C5104

DOUT

C210uF

C6104

C3104

DCLK

C7104

DIN

C10

01uF

CS

BUSY

C14 10uF

J1

CON6

123456

D1

DIODE

R5

47K

C9

10uF

C1310uF

Y1

OSC

OUT3

GND2

VCC4

U3

RSTVPP1

GND10

VCC20

XTAL15

XTAL24

P10AIN012P11AIN113P1214P1315P1416P1517P1618P1719

P30RXD2

P31TXD3

P32INT06

P33INT17

P34T08

P35T19

P3711

U4

C1+1

C1-3

C2+4

C2-5

VCC16

GND15

V+2

V-6

R1OUT12

R2OUT9

T1IN11

T2IN10

R1IN13

R2IN8

T1OUT14

T2OUT7

C12 10uF

C16

01uF

C15 10uF

C11

01uF

-5V

+5V

+5V

+5V

+5V

+5V

+5V

+5V

RST

OSC

OSC

RST

DCLKCSDINBUSYDOUT

U1

IN2

GND

4

OUT6

TEMP3

TRIM5

-5V

+5V

Electronic circuit diagram of the magnetic sensor

Photograph of the completed measuring system data acquisition

software in PC and probe scanning system

Experimental Setup for Magnetic Sensor

Reference material Scanning System Software LabVIEW

Reference Material (1) Normal defects and PVCs

Longitudinal and transverse defects

Def W L D Remarks

1 02 500 0213 (20 ) Inner defects

2 02 500 0427 (40 )

3 02 500 0213 (20 )Outer defectsPVC(1018)4 02 500 0427 (40 )

5 02 500 0639 (60 )

6 02 500 0852 (80 )

7 02 500 0639 (60 ) Inner defects

8 02 500 0852 (80 )

- 1 and 2 are inner defects

- 345 and 6 are outer defects with PVC

- 7 and 8 are inner defects

PVC

PVC

Defect Defect

For longitudinal defects and PVC For circumferential defects and PVC

ECT is very difficult to detect circumferential defects

We can distinguish PVCs and defects and longitudinal and circumferential defects

Flux-gate Magnetometer

One core sensor Two core sensor

3-축 flux-gate Magnetometer의 계략도

Sensorpia Co

pro

cess

or(

AV

R)

Sensor 1

RS422

Interface

Mic

ro-p

roce

ssor(

AV

R)

Sensor 2

Sensor 3

Interface

조립된 마그네토미터의 사진

Sensorpia Co

Analog PCB

Digital PCB

Sensorpia Co선형도(linearity)

10

20

30

40

50

60

y-axis

Magnetometer Output (microT)

-60 -50 -40 -30 -20 -10 0 10 20 30 40 50 60

-60

-50

-40

-30

-20

-10

0

10

Y-axis y=099946 x+0015STD 106E-4

Magnetometer Output (

Applied Magnetic Field (microT)

마그네토미터의 noise 특성 Sensorpia Co

1

10

100

y-axis

Magnetometer noise (nT)

0 1 2 3 4 5 6

1E-4

1E-3

001

01

Magnetometer noise (nT)

Frequency (Hz)

Magnetometer for KoDSAT

-150 -100 -50 0 50 100 150

-15

-10

-5

0

5

10

15

Magnetic Moment (Am

2)

Current (mA)

After Thermal Cycle Test

Measured

Resistance 193 ohm

Photograph of Magnetic torquer

Photograph of KoDSAT

Photograph of

3-axis Fluxgate

Magnetometer

Photograph of Magnetic torquer

Application of magnetometer

Moon magnetic fieldmeasurement

Telescope with direction indication

Joule Effect (Magnetostriction)

ϕ2cosel

l=

∆

0=∆

+∆

+∆

b

b

a

a

l

l

Actuator using Terfenol-D

00

05

10

B (T)

800

1000

1200

1400

1600

Magnetostriction (ppm)

-100 -50 0 50 100

-10

-05

00

B (T)

H (kAm)

2 MPa

4 MPa

6 MPa

8 MPa

10 MPa

12 MPa

-100 -50 0 50 100

-200

0

200

400

600

Magnetostriction (ppm)

H (kAm)

2 MPa

4 MPa

6 MPa

8 MPa

10 MPa

12 MPa

600

700

800

900

1000

-4 -3 -2 -1 0 1 2 3 4

0

10

20

30

40

50

60

Displacement (m

icro meter)

I (A)

FIELD

9 kAm

12 kAm

16 kAm

20 kAm

24 kAm

38 kAm

-50 -40 -30 -20 -10 0 10 20 30 40 50

-100

0

100

200

300

400

500

L (PPM)

H (kAm)

9 kAm

12 kAm

16 kAm

20 kAm

24 kAm

38 kAm

Magnetostrictive displacement sensor

Hysteresis loops under

tensile stress σ

(a) Crystalline 68 NiFe

λs = +25 10-6

(b) crystalline pure Ni λs

= -35 10-6

Villari Effect ( Inverse of Joule Effect)

= -35 10-6

(c) amorphous Co-based

alloy

λs = -35 10-6

ϕσλ 2sin2

3sdotsdot= smeE

γ

Permeability depending on the stress

σλmicromicro

1

3

2

Y

J

so

s

r =

γ

Calculated magnetization curves under stress

Variation of magnetization curve by an applied

tensile force (Co-based amorphous alloy)

Alloy Requirement

Materials for magnetoelastic sensors

Why amorphous magnetic materials are important

Stress-strain curves of several materials

Coercivity and hardness of several materials

Principles of magnetoelastic sensors

Non-contact torque sensor

Principle of cross torductor torque

sensor and flux pattern of sensor

poles on the surface of a shaft

a) without and b)with torsional load

Equivalent magnetic circuit of

cross type torque sensor

Helices of principal tensile and compressive stress on the surface of

a shaft subjected to torsion [32] Correlated changes of permeability

are detected by four-branch yoke system with sensing coils 123

and 4 and a common excitation pole

Examples of torque sensors

Four-branch type torque sensor

heads Pole structures realized

by commercial multi-pole

ferrites 14 and 18 min in

diameter (diameter of sensor

h e a d 1 7 a n d 2 4 m m

respectively) respectively)

Principle of Ring Torductor torque transducer

(a b) Physical structure (c) evolution of the

shaft surface under the transducer poles A and BRing torductor for measuring

torque on ship propeller shafts

(shaft diameter ca 500 mm)

(Courtesy ASEA Brown

Boveri AG)

Principal designs of coaxial torque sensors

Schematic diagram of data processing

electronics of a torque sensor

Extensometer (a) Construction of strain sensing element using

amorphous ribbon wound core (b) configuration of lumped

windings

∆E effect of an amorphous FeNi-based

alloy (Fe40 Ni38 Mo4 B18) Hs saturation

field

Magnetically tunable delay line

Torque Sensors using Amorphous wire

Sixtus tonk효과(large Barkhausen효과)

Hysteresis loops of a Wiegand wire for different reset fields

Curie 온도 및Hopkinson효과

Relation between normalised

saturation polarisation and

normalised Curie temperature

Permeability of a Mn-Zn ferrite as

a function of temperature and field

strength

Conclusions

1) Magnetic sensor 는 자동차 공장자동화 항공우주 및 군사용으로많이 사용되고 있다

2) 새로운 소재개발은 자기센서의 성능개발에 직접적인 영향을 준다2) 새로운 소재개발은 자기센서의 성능개발에 직접적인 영향을 준다

3) 센서의 개발을 위해서는 다양한 전공지식이 요구된다

(물리학 재료공학 기계공학 전자공학)

4) 센서분야가 고부가가치를 창출하는 부품사업이다

5) 핵심부품을 생산하는 중소기업의 item으로도 적절하다

Signal Conditioning

Schematic electrical diagram of a force transducer connected with an

amplifier (courtesy Hottinger Baldwin Messtechnik GmbH)

Variable Gap Sensors

)( FeFe2

0 LLllANL micromicromicro +sdotsdot=

FeFe2

0max lANL sdotsdotsdot= micromicro

Construction of a variable gap sensor

Characteristic of a variable gap sensor

Construction of a differential

cross-anchor sensor

Output voltage U versus core

position x plusmn a limits of the

linear rage

Applications of differential cross-anchor sensors

AC-excited Sensors for Rotary Movements

Principle of construction of a synchro

α cos10 sdotsdot= UKU y

)120-( cos10 degsdotsdot= αUKU z

)240-( cos10 degsdotsdot= αUKU x

)120-( sin3100 degsdotsdotsdot=minus= αKUUUU yxyx

)240-( sin3100 degsdotsdotsdot=minus= αKUUUU zyzy

α sin3100 sdotsdotsdot=minus= KUUUU xzxz

Application to the Torque Sensor

Principle of construction of a torque-type synchro

Torque versus angular

difference

)( sin~ rt αα minussdotKM

)( cos~ rt1r αα minussdotUU

Principle of construction of a control-type sensor

Output voltage versus

angular difference

Principle of construction of a differential sychro

Eddy Current Sensors

tBE dd curl minus=JH = curl

0 div =BH(H)B sdot= micro

E(E)J sdot= σ

A B curl= A B curl=

tdd- A E =

)dd( tAJ minus= σ

tdd curl curl AA σmicro minus=

AA) σωmicro iminus= curl )(curl(1

AA) σωmicro i=∆)((1

Eddy Current Tachometer

Construction of a speedometer (courtesy VDO Adolf Schinding AG) 1) spindle 2) bearing

3) holding spring 4) iron yoke 5) eddy current cup 6) shaft of the magnet 7) support of

the magnet 8) temperature compensation 9) permanent magnet 10) torsion spring

Proximity Sensors

Schematic diagram of a proximity sensor

Output current of a proximity switch versus distance

Inductive Flowmeters

)( Btimessdot= υqF

EqF sdot=BE times=υ

)(ds Btimes== υEU )(ds Btimes== υEU

)( Bd timessdot= υU

Bsdotsdotsdot= υdKU

Development of magnetic phase detection

sensor for steam generator tube

Dirac Son1 Kwan-Sang Ryu2 Duck-Gun Park3

1Hannam University Daejeon Rep of Korea2Korea Research Institute of Standards and Science Daejeon Rep of Korea3KoreaAtomic Energy Research Institute Daejeon Rep of Korea

Introduction

The layout of pressurized water reactor (PWR) components

Primary side Secondary side (non-radioactive side)(radioactive side)

The Structure of SG(Steam Generator)(degradation mechanism)

Secondary SidePrimary Side

SCC

A B

A-B

Steam outlet

Anti-vibration

SCC

Fretting

Wall thinning

IGA

U-bend

In commercial power plants SG- height up to 21 m - weight up to 800 tons - 2~4 sets of SG were installed - SG can contain from 3000 to

16000 tubes each about 20 mmin diameter

Primary coolant outlet Primary coolant inlet

Anti-vibrationbars

Tubesupportplate

Tubesheet

IGA

SCC

Pitting

SCC

Inside Tubesheet

Top of Tubesheet

by SSHwang of KAERI

Denting

Sludge pile

in diameter

The SGT is made of nickel basedInconel alloy which is composed of 75 Ni 165Cr and 815Fe

-Degradation mechanism corrosion pitting denting inter granular attack

-Inspection Eddy current Testing(ECT)

Permeability Variation Clusters (PVC)

(Ferro-magnetic phase)

-005

000

005

010

015

m (emug)

1-1

-002

000

002

004

006

008

m (emug)

1-2

-1000 -500 0 500 1000

-015

-010

-005

H ( Am )

-1000 -500 0 500 1000

-006

-004

-002

H ( Am )

The hystresis loop in the fragment of PVC parts of Kori-1 retired SG tube

-004

-002

000

002

004

006

M (emug)

Inconel 600 tested at RT

under tensile stress

1 2 3

4 5 6

7 8 9-004

-002

000

002

004

006

M(emug)

Inconel 600 Heat treated at

602 oC under tensile stress

1 2 3

How can we detect magnetic phase

(PVC)selectively from the flaws in SGT

-3000 -2000 -1000 0 1000 2000 3000

-006

H (Oe)

7 8 9

10 11 12

-3000 -2000 -1000 0 1000 2000 3000

-006

-004

H(Oe)

4 5 6

7 8 9

The hysteresis loop of the tensile tested specimen at room temperature (a) and tensile tested at high temperature (b)

The magnetic phase can be created under the high temperature andpressure conditions which is correspond to the stress corrosion crackingin the SG tube in the NPP(Bruemmer SM Charlot LA amp Henager CH (1988) Corrosion 782)

Principle of ECT

If we can separate magnetic phase selectively from the

flaws using magnetic sensor the reliability of EC in SGT

inspection will be greatly enhanced

Structure of the permeability

sensor

Dimension and photograph of U-shape

sensing yoke

Design of Magnetic Sensor for PVC

sensor sensing yoke

Photograph of the completed sensor front side (above) and rear side (bottom)

R11R12

R10

R8

R6

R9

R13

R7

R14

C18

1 n

C17

C20

C21

D2

DIODE

SIN COS

-

+

U-2A

4

13

2

-

+

U-2B

75

6

8

-

+

U-3A

13

2

8

+5VC19

104

+5V

Schematic diagram of the sensor system

Electronic Circuit of Magnetic Sensor

R20

R

R21

R

-

+

U5AD797

3

26

74

U6

D1

S12

GND3

+VCC4VCC5

IN6

-VCC7

S28

C41

R13

R26

R18

R25

R2210 Ω

R16

R14

R17

10 k

R15

R27

R32

R28

R33

R29

R34

5 k

R30

C29

C37

104

C32473

C39473C40

104

C33

104

C21

104C23

104

C25

104

C26

104

C30

104

C31

104

C35

104

C36

104

C27

104

C28

104

C34

104

C38

104

D3

DIODE

L1

1

2

L2

1

2

L3

1

2

4

-

+

U-4A

4

13

2

-

+

U-4B

75

6

8

-

+

U-5A

4

13

2

-

+

U-5B

75

6

8

-

+

U-6A

4

13

2

-

+

U-6B

75

6

8

C22

104

-5V

+5V

+5V

+5V

+5V

+5V

+5V

U7

D1

S12

GND3

+VCC4

VCC5

IN6

-VCC7

S28

+5V

-5V

-5V

-5V

-5V

-5V

-5V

-5V

-5V

R19

R24

R

R23

R

C24

OUT(X)

OUT(Y)

R1

20 kR210 k

R3

20 kR410 k

C1

104

C8

104

REF43

OUT(X)

OUT(Y)

REF43

U2

+Vcc1

CH02

CH13

CH24

CH35

COMM6

SHDN7

Vref8

+Vcc9

GND10

GND11

DOUT12BUSY13DIN14CS15

DIN16

-

+

U-1A

13

2

8

-

+

U-1B

4

75

6

C410 uF

C5104

DOUT

C210uF

C6104

C3104

DCLK

C7104

DIN

C10

01uF

CS

BUSY

C14 10uF

J1

CON6

123456

D1

DIODE

R5

47K

C9

10uF

C1310uF

Y1

OSC

OUT3

GND2

VCC4

U3

RSTVPP1

GND10

VCC20

XTAL15

XTAL24

P10AIN012P11AIN113P1214P1315P1416P1517P1618P1719

P30RXD2

P31TXD3

P32INT06

P33INT17

P34T08

P35T19

P3711

U4

C1+1

C1-3

C2+4

C2-5

VCC16

GND15

V+2

V-6

R1OUT12

R2OUT9

T1IN11

T2IN10

R1IN13

R2IN8

T1OUT14

T2OUT7

C12 10uF

C16

01uF

C15 10uF

C11

01uF

-5V

+5V

+5V

+5V

+5V

+5V

+5V

+5V

RST

OSC

OSC

RST

DCLKCSDINBUSYDOUT

U1

IN2

GND

4

OUT6

TEMP3

TRIM5

-5V

+5V

Electronic circuit diagram of the magnetic sensor

Photograph of the completed measuring system data acquisition

software in PC and probe scanning system

Experimental Setup for Magnetic Sensor

Reference material Scanning System Software LabVIEW

Reference Material (1) Normal defects and PVCs

Longitudinal and transverse defects

Def W L D Remarks

1 02 500 0213 (20 ) Inner defects

2 02 500 0427 (40 )

3 02 500 0213 (20 )Outer defectsPVC(1018)4 02 500 0427 (40 )

5 02 500 0639 (60 )

6 02 500 0852 (80 )

7 02 500 0639 (60 ) Inner defects

8 02 500 0852 (80 )

- 1 and 2 are inner defects

- 345 and 6 are outer defects with PVC

- 7 and 8 are inner defects

PVC

PVC

Defect Defect

For longitudinal defects and PVC For circumferential defects and PVC

ECT is very difficult to detect circumferential defects

We can distinguish PVCs and defects and longitudinal and circumferential defects

Flux-gate Magnetometer

One core sensor Two core sensor

3-축 flux-gate Magnetometer의 계략도

Sensorpia Co

pro

cess

or(

AV

R)

Sensor 1

RS422

Interface

Mic

ro-p

roce

ssor(

AV

R)

Sensor 2

Sensor 3

Interface

조립된 마그네토미터의 사진

Sensorpia Co

Analog PCB

Digital PCB

Sensorpia Co선형도(linearity)

10

20

30

40

50

60

y-axis

Magnetometer Output (microT)

-60 -50 -40 -30 -20 -10 0 10 20 30 40 50 60

-60

-50

-40

-30

-20

-10

0

10

Y-axis y=099946 x+0015STD 106E-4

Magnetometer Output (

Applied Magnetic Field (microT)

마그네토미터의 noise 특성 Sensorpia Co

1

10

100

y-axis

Magnetometer noise (nT)

0 1 2 3 4 5 6

1E-4

1E-3

001

01

Magnetometer noise (nT)

Frequency (Hz)

Magnetometer for KoDSAT

-150 -100 -50 0 50 100 150

-15

-10

-5

0

5

10

15

Magnetic Moment (Am

2)

Current (mA)

After Thermal Cycle Test

Measured

Resistance 193 ohm

Photograph of Magnetic torquer

Photograph of KoDSAT

Photograph of

3-axis Fluxgate

Magnetometer

Photograph of Magnetic torquer

Application of magnetometer

Moon magnetic fieldmeasurement

Telescope with direction indication

Joule Effect (Magnetostriction)

ϕ2cosel

l=

∆

0=∆

+∆

+∆

b

b

a

a

l

l

Actuator using Terfenol-D

00

05

10

B (T)

800

1000

1200

1400

1600

Magnetostriction (ppm)

-100 -50 0 50 100

-10

-05

00

B (T)

H (kAm)

2 MPa

4 MPa

6 MPa

8 MPa

10 MPa

12 MPa

-100 -50 0 50 100

-200

0

200

400

600

Magnetostriction (ppm)

H (kAm)

2 MPa

4 MPa

6 MPa

8 MPa

10 MPa

12 MPa

600

700

800

900

1000

-4 -3 -2 -1 0 1 2 3 4

0

10

20

30

40

50

60

Displacement (m

icro meter)

I (A)

FIELD

9 kAm

12 kAm

16 kAm

20 kAm

24 kAm

38 kAm

-50 -40 -30 -20 -10 0 10 20 30 40 50

-100

0

100

200

300

400

500

L (PPM)

H (kAm)

9 kAm

12 kAm

16 kAm

20 kAm

24 kAm

38 kAm

Magnetostrictive displacement sensor

Hysteresis loops under

tensile stress σ

(a) Crystalline 68 NiFe

λs = +25 10-6

(b) crystalline pure Ni λs

= -35 10-6

Villari Effect ( Inverse of Joule Effect)

= -35 10-6

(c) amorphous Co-based

alloy

λs = -35 10-6

ϕσλ 2sin2

3sdotsdot= smeE

γ

Permeability depending on the stress

σλmicromicro

1

3

2

Y

J

so

s

r =

γ

Calculated magnetization curves under stress

Variation of magnetization curve by an applied

tensile force (Co-based amorphous alloy)

Alloy Requirement

Materials for magnetoelastic sensors

Why amorphous magnetic materials are important

Stress-strain curves of several materials

Coercivity and hardness of several materials

Principles of magnetoelastic sensors

Non-contact torque sensor

Principle of cross torductor torque

sensor and flux pattern of sensor

poles on the surface of a shaft

a) without and b)with torsional load

Equivalent magnetic circuit of

cross type torque sensor

Helices of principal tensile and compressive stress on the surface of

a shaft subjected to torsion [32] Correlated changes of permeability

are detected by four-branch yoke system with sensing coils 123

and 4 and a common excitation pole

Examples of torque sensors

Four-branch type torque sensor

heads Pole structures realized

by commercial multi-pole

ferrites 14 and 18 min in

diameter (diameter of sensor

h e a d 1 7 a n d 2 4 m m

respectively) respectively)

Principle of Ring Torductor torque transducer

(a b) Physical structure (c) evolution of the

shaft surface under the transducer poles A and BRing torductor for measuring

torque on ship propeller shafts

(shaft diameter ca 500 mm)

(Courtesy ASEA Brown

Boveri AG)

Principal designs of coaxial torque sensors

Schematic diagram of data processing

electronics of a torque sensor

Extensometer (a) Construction of strain sensing element using

amorphous ribbon wound core (b) configuration of lumped

windings

∆E effect of an amorphous FeNi-based

alloy (Fe40 Ni38 Mo4 B18) Hs saturation

field

Magnetically tunable delay line

Torque Sensors using Amorphous wire

Sixtus tonk효과(large Barkhausen효과)

Hysteresis loops of a Wiegand wire for different reset fields

Curie 온도 및Hopkinson효과

Relation between normalised

saturation polarisation and

normalised Curie temperature

Permeability of a Mn-Zn ferrite as

a function of temperature and field

strength

Conclusions

1) Magnetic sensor 는 자동차 공장자동화 항공우주 및 군사용으로많이 사용되고 있다

2) 새로운 소재개발은 자기센서의 성능개발에 직접적인 영향을 준다2) 새로운 소재개발은 자기센서의 성능개발에 직접적인 영향을 준다

3) 센서의 개발을 위해서는 다양한 전공지식이 요구된다

(물리학 재료공학 기계공학 전자공학)

4) 센서분야가 고부가가치를 창출하는 부품사업이다

5) 핵심부품을 생산하는 중소기업의 item으로도 적절하다

Variable Gap Sensors

)( FeFe2

0 LLllANL micromicromicro +sdotsdot=

FeFe2

0max lANL sdotsdotsdot= micromicro

Construction of a variable gap sensor

Characteristic of a variable gap sensor

Construction of a differential

cross-anchor sensor

Output voltage U versus core

position x plusmn a limits of the

linear rage

Applications of differential cross-anchor sensors

AC-excited Sensors for Rotary Movements

Principle of construction of a synchro

α cos10 sdotsdot= UKU y

)120-( cos10 degsdotsdot= αUKU z

)240-( cos10 degsdotsdot= αUKU x

)120-( sin3100 degsdotsdotsdot=minus= αKUUUU yxyx

)240-( sin3100 degsdotsdotsdot=minus= αKUUUU zyzy

α sin3100 sdotsdotsdot=minus= KUUUU xzxz

Application to the Torque Sensor

Principle of construction of a torque-type synchro

Torque versus angular

difference

)( sin~ rt αα minussdotKM

)( cos~ rt1r αα minussdotUU

Principle of construction of a control-type sensor

Output voltage versus

angular difference

Principle of construction of a differential sychro

Eddy Current Sensors

tBE dd curl minus=JH = curl

0 div =BH(H)B sdot= micro

E(E)J sdot= σ

A B curl= A B curl=

tdd- A E =

)dd( tAJ minus= σ

tdd curl curl AA σmicro minus=

AA) σωmicro iminus= curl )(curl(1

AA) σωmicro i=∆)((1

Eddy Current Tachometer

Construction of a speedometer (courtesy VDO Adolf Schinding AG) 1) spindle 2) bearing

3) holding spring 4) iron yoke 5) eddy current cup 6) shaft of the magnet 7) support of

the magnet 8) temperature compensation 9) permanent magnet 10) torsion spring

Proximity Sensors

Schematic diagram of a proximity sensor

Output current of a proximity switch versus distance

Inductive Flowmeters

)( Btimessdot= υqF

EqF sdot=BE times=υ

)(ds Btimes== υEU )(ds Btimes== υEU

)( Bd timessdot= υU

Bsdotsdotsdot= υdKU

Development of magnetic phase detection

sensor for steam generator tube

Dirac Son1 Kwan-Sang Ryu2 Duck-Gun Park3

1Hannam University Daejeon Rep of Korea2Korea Research Institute of Standards and Science Daejeon Rep of Korea3KoreaAtomic Energy Research Institute Daejeon Rep of Korea

Introduction

The layout of pressurized water reactor (PWR) components

Primary side Secondary side (non-radioactive side)(radioactive side)

The Structure of SG(Steam Generator)(degradation mechanism)

Secondary SidePrimary Side

SCC

A B

A-B

Steam outlet

Anti-vibration

SCC

Fretting

Wall thinning

IGA

U-bend

In commercial power plants SG- height up to 21 m - weight up to 800 tons - 2~4 sets of SG were installed - SG can contain from 3000 to

16000 tubes each about 20 mmin diameter

Primary coolant outlet Primary coolant inlet

Anti-vibrationbars

Tubesupportplate

Tubesheet

IGA

SCC

Pitting

SCC

Inside Tubesheet

Top of Tubesheet

by SSHwang of KAERI

Denting

Sludge pile

in diameter

The SGT is made of nickel basedInconel alloy which is composed of 75 Ni 165Cr and 815Fe

-Degradation mechanism corrosion pitting denting inter granular attack

-Inspection Eddy current Testing(ECT)

Permeability Variation Clusters (PVC)

(Ferro-magnetic phase)

-005

000

005

010

015

m (emug)

1-1

-002

000

002

004

006

008

m (emug)

1-2

-1000 -500 0 500 1000

-015

-010

-005

H ( Am )

-1000 -500 0 500 1000

-006

-004

-002

H ( Am )

The hystresis loop in the fragment of PVC parts of Kori-1 retired SG tube

-004

-002

000

002

004

006

M (emug)

Inconel 600 tested at RT

under tensile stress

1 2 3

4 5 6

7 8 9-004

-002

000

002

004

006

M(emug)

Inconel 600 Heat treated at

602 oC under tensile stress

1 2 3

How can we detect magnetic phase

(PVC)selectively from the flaws in SGT

-3000 -2000 -1000 0 1000 2000 3000

-006

H (Oe)

7 8 9

10 11 12

-3000 -2000 -1000 0 1000 2000 3000

-006

-004

H(Oe)

4 5 6

7 8 9

The hysteresis loop of the tensile tested specimen at room temperature (a) and tensile tested at high temperature (b)

The magnetic phase can be created under the high temperature andpressure conditions which is correspond to the stress corrosion crackingin the SG tube in the NPP(Bruemmer SM Charlot LA amp Henager CH (1988) Corrosion 782)

Principle of ECT

If we can separate magnetic phase selectively from the

flaws using magnetic sensor the reliability of EC in SGT

inspection will be greatly enhanced

Structure of the permeability

sensor

Dimension and photograph of U-shape

sensing yoke

Design of Magnetic Sensor for PVC

sensor sensing yoke

Photograph of the completed sensor front side (above) and rear side (bottom)

R11R12

R10

R8

R6

R9

R13

R7

R14

C18

1 n

C17

C20

C21

D2

DIODE

SIN COS

-

+

U-2A

4

13

2

-

+

U-2B

75

6

8

-

+

U-3A

13

2

8

+5VC19

104

+5V

Schematic diagram of the sensor system

Electronic Circuit of Magnetic Sensor

R20

R

R21

R

-

+

U5AD797

3

26

74

U6

D1

S12

GND3

+VCC4VCC5

IN6

-VCC7

S28

C41

R13

R26

R18

R25

R2210 Ω

R16

R14

R17

10 k

R15

R27

R32

R28

R33

R29

R34

5 k

R30

C29

C37

104

C32473

C39473C40

104

C33

104

C21

104C23

104

C25

104

C26

104

C30

104

C31

104

C35

104

C36

104

C27

104

C28

104

C34

104

C38

104

D3

DIODE

L1

1

2

L2

1

2

L3

1

2

4

-

+

U-4A

4

13

2

-

+

U-4B

75

6

8

-

+

U-5A

4

13

2

-

+

U-5B

75

6

8

-

+

U-6A

4

13

2

-

+

U-6B

75

6

8

C22

104

-5V

+5V

+5V

+5V

+5V

+5V

+5V

U7

D1

S12

GND3

+VCC4

VCC5

IN6

-VCC7

S28

+5V

-5V

-5V

-5V

-5V

-5V

-5V

-5V

-5V

R19

R24

R

R23

R

C24

OUT(X)

OUT(Y)

R1

20 kR210 k

R3

20 kR410 k

C1

104

C8

104

REF43

OUT(X)

OUT(Y)

REF43

U2

+Vcc1

CH02

CH13

CH24

CH35

COMM6

SHDN7

Vref8

+Vcc9

GND10

GND11

DOUT12BUSY13DIN14CS15

DIN16

-

+

U-1A

13

2

8

-

+

U-1B

4

75

6

C410 uF

C5104

DOUT

C210uF

C6104

C3104

DCLK

C7104

DIN

C10

01uF

CS

BUSY

C14 10uF

J1

CON6

123456

D1

DIODE

R5

47K

C9

10uF

C1310uF

Y1

OSC

OUT3

GND2

VCC4

U3

RSTVPP1

GND10

VCC20

XTAL15

XTAL24

P10AIN012P11AIN113P1214P1315P1416P1517P1618P1719

P30RXD2

P31TXD3

P32INT06

P33INT17

P34T08

P35T19

P3711

U4

C1+1

C1-3

C2+4

C2-5

VCC16

GND15

V+2

V-6

R1OUT12

R2OUT9

T1IN11

T2IN10

R1IN13

R2IN8

T1OUT14

T2OUT7

C12 10uF

C16

01uF

C15 10uF

C11

01uF

-5V

+5V

+5V

+5V

+5V

+5V

+5V

+5V

RST

OSC

OSC

RST

DCLKCSDINBUSYDOUT

U1

IN2

GND

4

OUT6

TEMP3

TRIM5

-5V

+5V

Electronic circuit diagram of the magnetic sensor

Photograph of the completed measuring system data acquisition

software in PC and probe scanning system

Experimental Setup for Magnetic Sensor

Reference material Scanning System Software LabVIEW

Reference Material (1) Normal defects and PVCs

Longitudinal and transverse defects

Def W L D Remarks

1 02 500 0213 (20 ) Inner defects

2 02 500 0427 (40 )

3 02 500 0213 (20 )Outer defectsPVC(1018)4 02 500 0427 (40 )

5 02 500 0639 (60 )

6 02 500 0852 (80 )

7 02 500 0639 (60 ) Inner defects

8 02 500 0852 (80 )

- 1 and 2 are inner defects

- 345 and 6 are outer defects with PVC

- 7 and 8 are inner defects

PVC

PVC

Defect Defect

For longitudinal defects and PVC For circumferential defects and PVC

ECT is very difficult to detect circumferential defects

We can distinguish PVCs and defects and longitudinal and circumferential defects

Flux-gate Magnetometer

One core sensor Two core sensor

3-축 flux-gate Magnetometer의 계략도

Sensorpia Co

pro

cess

or(

AV

R)

Sensor 1

RS422

Interface

Mic

ro-p

roce

ssor(

AV

R)

Sensor 2

Sensor 3

Interface

조립된 마그네토미터의 사진

Sensorpia Co

Analog PCB

Digital PCB

Sensorpia Co선형도(linearity)

10

20

30

40

50

60

y-axis

Magnetometer Output (microT)

-60 -50 -40 -30 -20 -10 0 10 20 30 40 50 60

-60

-50

-40

-30

-20

-10

0

10

Y-axis y=099946 x+0015STD 106E-4

Magnetometer Output (

Applied Magnetic Field (microT)

마그네토미터의 noise 특성 Sensorpia Co

1

10

100

y-axis

Magnetometer noise (nT)

0 1 2 3 4 5 6

1E-4

1E-3

001

01

Magnetometer noise (nT)

Frequency (Hz)

Magnetometer for KoDSAT

-150 -100 -50 0 50 100 150

-15

-10

-5

0

5

10

15

Magnetic Moment (Am

2)

Current (mA)

After Thermal Cycle Test

Measured

Resistance 193 ohm

Photograph of Magnetic torquer

Photograph of KoDSAT

Photograph of

3-axis Fluxgate

Magnetometer

Photograph of Magnetic torquer

Application of magnetometer

Moon magnetic fieldmeasurement

Telescope with direction indication

Joule Effect (Magnetostriction)

ϕ2cosel

l=

∆

0=∆

+∆

+∆

b

b

a

a

l

l

Actuator using Terfenol-D

00

05

10

B (T)

800

1000

1200

1400

1600

Magnetostriction (ppm)

-100 -50 0 50 100

-10

-05

00

B (T)

H (kAm)

2 MPa

4 MPa

6 MPa

8 MPa

10 MPa

12 MPa

-100 -50 0 50 100

-200

0

200

400

600

Magnetostriction (ppm)

H (kAm)

2 MPa

4 MPa

6 MPa

8 MPa

10 MPa

12 MPa

600

700

800

900

1000

-4 -3 -2 -1 0 1 2 3 4

0

10

20

30

40

50

60

Displacement (m

icro meter)

I (A)

FIELD

9 kAm

12 kAm

16 kAm

20 kAm

24 kAm

38 kAm

-50 -40 -30 -20 -10 0 10 20 30 40 50

-100

0

100

200

300

400

500

L (PPM)

H (kAm)

9 kAm

12 kAm

16 kAm

20 kAm

24 kAm

38 kAm

Magnetostrictive displacement sensor

Hysteresis loops under

tensile stress σ

(a) Crystalline 68 NiFe

λs = +25 10-6

(b) crystalline pure Ni λs

= -35 10-6

Villari Effect ( Inverse of Joule Effect)

= -35 10-6

(c) amorphous Co-based

alloy

λs = -35 10-6

ϕσλ 2sin2

3sdotsdot= smeE

γ

Permeability depending on the stress

σλmicromicro

1

3

2

Y

J

so

s

r =

γ

Calculated magnetization curves under stress

Variation of magnetization curve by an applied

tensile force (Co-based amorphous alloy)

Alloy Requirement

Materials for magnetoelastic sensors

Why amorphous magnetic materials are important

Stress-strain curves of several materials

Coercivity and hardness of several materials

Principles of magnetoelastic sensors

Non-contact torque sensor

Principle of cross torductor torque

sensor and flux pattern of sensor

poles on the surface of a shaft

a) without and b)with torsional load

Equivalent magnetic circuit of

cross type torque sensor

Helices of principal tensile and compressive stress on the surface of

a shaft subjected to torsion [32] Correlated changes of permeability

are detected by four-branch yoke system with sensing coils 123

and 4 and a common excitation pole

Examples of torque sensors

Four-branch type torque sensor

heads Pole structures realized

by commercial multi-pole

ferrites 14 and 18 min in

diameter (diameter of sensor

h e a d 1 7 a n d 2 4 m m

respectively) respectively)

Principle of Ring Torductor torque transducer

(a b) Physical structure (c) evolution of the

shaft surface under the transducer poles A and BRing torductor for measuring

torque on ship propeller shafts

(shaft diameter ca 500 mm)

(Courtesy ASEA Brown

Boveri AG)

Principal designs of coaxial torque sensors

Schematic diagram of data processing

electronics of a torque sensor

Extensometer (a) Construction of strain sensing element using

amorphous ribbon wound core (b) configuration of lumped

windings

∆E effect of an amorphous FeNi-based

alloy (Fe40 Ni38 Mo4 B18) Hs saturation

field

Magnetically tunable delay line

Torque Sensors using Amorphous wire

Sixtus tonk효과(large Barkhausen효과)

Hysteresis loops of a Wiegand wire for different reset fields

Curie 온도 및Hopkinson효과

Relation between normalised

saturation polarisation and

normalised Curie temperature

Permeability of a Mn-Zn ferrite as

a function of temperature and field

strength

Conclusions

1) Magnetic sensor 는 자동차 공장자동화 항공우주 및 군사용으로많이 사용되고 있다

2) 새로운 소재개발은 자기센서의 성능개발에 직접적인 영향을 준다2) 새로운 소재개발은 자기센서의 성능개발에 직접적인 영향을 준다

3) 센서의 개발을 위해서는 다양한 전공지식이 요구된다

(물리학 재료공학 기계공학 전자공학)

4) 센서분야가 고부가가치를 창출하는 부품사업이다

5) 핵심부품을 생산하는 중소기업의 item으로도 적절하다

Construction of a differential

cross-anchor sensor

Output voltage U versus core

position x plusmn a limits of the

linear rage

Applications of differential cross-anchor sensors

AC-excited Sensors for Rotary Movements

Principle of construction of a synchro

α cos10 sdotsdot= UKU y

)120-( cos10 degsdotsdot= αUKU z

)240-( cos10 degsdotsdot= αUKU x

)120-( sin3100 degsdotsdotsdot=minus= αKUUUU yxyx

)240-( sin3100 degsdotsdotsdot=minus= αKUUUU zyzy

α sin3100 sdotsdotsdot=minus= KUUUU xzxz

Application to the Torque Sensor

Principle of construction of a torque-type synchro

Torque versus angular

difference

)( sin~ rt αα minussdotKM

)( cos~ rt1r αα minussdotUU

Principle of construction of a control-type sensor

Output voltage versus

angular difference

Principle of construction of a differential sychro

Eddy Current Sensors

tBE dd curl minus=JH = curl

0 div =BH(H)B sdot= micro

E(E)J sdot= σ

A B curl= A B curl=

tdd- A E =

)dd( tAJ minus= σ

tdd curl curl AA σmicro minus=

AA) σωmicro iminus= curl )(curl(1

AA) σωmicro i=∆)((1

Eddy Current Tachometer

Construction of a speedometer (courtesy VDO Adolf Schinding AG) 1) spindle 2) bearing

3) holding spring 4) iron yoke 5) eddy current cup 6) shaft of the magnet 7) support of

the magnet 8) temperature compensation 9) permanent magnet 10) torsion spring

Proximity Sensors

Schematic diagram of a proximity sensor

Output current of a proximity switch versus distance

Inductive Flowmeters

)( Btimessdot= υqF

EqF sdot=BE times=υ

)(ds Btimes== υEU )(ds Btimes== υEU

)( Bd timessdot= υU

Bsdotsdotsdot= υdKU

Development of magnetic phase detection

sensor for steam generator tube

Dirac Son1 Kwan-Sang Ryu2 Duck-Gun Park3

1Hannam University Daejeon Rep of Korea2Korea Research Institute of Standards and Science Daejeon Rep of Korea3KoreaAtomic Energy Research Institute Daejeon Rep of Korea

Introduction

The layout of pressurized water reactor (PWR) components

Primary side Secondary side (non-radioactive side)(radioactive side)

The Structure of SG(Steam Generator)(degradation mechanism)

Secondary SidePrimary Side

SCC

A B

A-B

Steam outlet

Anti-vibration

SCC

Fretting

Wall thinning

IGA

U-bend

In commercial power plants SG- height up to 21 m - weight up to 800 tons - 2~4 sets of SG were installed - SG can contain from 3000 to

16000 tubes each about 20 mmin diameter

Primary coolant outlet Primary coolant inlet

Anti-vibrationbars

Tubesupportplate

Tubesheet

IGA

SCC

Pitting

SCC

Inside Tubesheet

Top of Tubesheet

by SSHwang of KAERI

Denting

Sludge pile

in diameter

The SGT is made of nickel basedInconel alloy which is composed of 75 Ni 165Cr and 815Fe

-Degradation mechanism corrosion pitting denting inter granular attack

-Inspection Eddy current Testing(ECT)

Permeability Variation Clusters (PVC)

(Ferro-magnetic phase)

-005

000

005

010

015

m (emug)

1-1

-002

000

002

004

006

008

m (emug)

1-2

-1000 -500 0 500 1000

-015

-010

-005

H ( Am )

-1000 -500 0 500 1000

-006

-004

-002

H ( Am )

The hystresis loop in the fragment of PVC parts of Kori-1 retired SG tube

-004

-002

000

002

004

006

M (emug)

Inconel 600 tested at RT

under tensile stress

1 2 3

4 5 6

7 8 9-004

-002

000

002

004

006

M(emug)

Inconel 600 Heat treated at

602 oC under tensile stress

1 2 3

How can we detect magnetic phase

(PVC)selectively from the flaws in SGT

-3000 -2000 -1000 0 1000 2000 3000

-006

H (Oe)

7 8 9

10 11 12

-3000 -2000 -1000 0 1000 2000 3000

-006

-004

H(Oe)

4 5 6

7 8 9

The hysteresis loop of the tensile tested specimen at room temperature (a) and tensile tested at high temperature (b)

The magnetic phase can be created under the high temperature andpressure conditions which is correspond to the stress corrosion crackingin the SG tube in the NPP(Bruemmer SM Charlot LA amp Henager CH (1988) Corrosion 782)

Principle of ECT

If we can separate magnetic phase selectively from the

flaws using magnetic sensor the reliability of EC in SGT

inspection will be greatly enhanced

Structure of the permeability

sensor

Dimension and photograph of U-shape

sensing yoke

Design of Magnetic Sensor for PVC

sensor sensing yoke

Photograph of the completed sensor front side (above) and rear side (bottom)

R11R12

R10

R8

R6

R9

R13

R7

R14

C18

1 n

C17

C20

C21

D2

DIODE

SIN COS

-

+

U-2A

4

13

2

-

+

U-2B

75

6

8

-

+

U-3A

13

2

8

+5VC19

104

+5V

Schematic diagram of the sensor system

Electronic Circuit of Magnetic Sensor

R20

R

R21

R

-

+

U5AD797

3

26

74

U6

D1

S12

GND3

+VCC4VCC5

IN6

-VCC7

S28

C41

R13

R26

R18

R25

R2210 Ω

R16

R14

R17

10 k

R15

R27

R32

R28

R33

R29

R34

5 k

R30

C29

C37

104

C32473

C39473C40

104

C33

104

C21

104C23

104

C25

104

C26

104

C30

104

C31

104

C35

104

C36

104

C27

104

C28

104

C34

104

C38

104

D3

DIODE

L1

1

2

L2

1

2

L3

1

2

4

-

+

U-4A

4

13

2

-

+

U-4B

75

6

8

-

+

U-5A

4

13

2

-

+

U-5B

75

6

8

-

+

U-6A

4

13

2

-

+

U-6B

75

6

8

C22

104

-5V

+5V

+5V

+5V

+5V

+5V

+5V

U7

D1

S12

GND3

+VCC4

VCC5

IN6

-VCC7

S28

+5V

-5V

-5V

-5V

-5V

-5V

-5V

-5V

-5V

R19

R24

R

R23

R

C24

OUT(X)

OUT(Y)

R1

20 kR210 k

R3

20 kR410 k

C1

104

C8

104

REF43

OUT(X)

OUT(Y)

REF43

U2

+Vcc1

CH02

CH13

CH24

CH35

COMM6

SHDN7

Vref8

+Vcc9

GND10

GND11

DOUT12BUSY13DIN14CS15

DIN16

-

+

U-1A

13

2

8

-

+

U-1B

4

75

6

C410 uF

C5104

DOUT

C210uF

C6104

C3104

DCLK

C7104

DIN

C10

01uF

CS

BUSY

C14 10uF

J1

CON6

123456

D1

DIODE

R5

47K

C9

10uF

C1310uF

Y1

OSC

OUT3

GND2

VCC4

U3

RSTVPP1

GND10

VCC20

XTAL15

XTAL24

P10AIN012P11AIN113P1214P1315P1416P1517P1618P1719

P30RXD2

P31TXD3

P32INT06

P33INT17

P34T08

P35T19

P3711

U4

C1+1

C1-3

C2+4

C2-5

VCC16

GND15

V+2

V-6

R1OUT12

R2OUT9

T1IN11

T2IN10

R1IN13

R2IN8

T1OUT14

T2OUT7

C12 10uF

C16

01uF

C15 10uF

C11

01uF

-5V

+5V

+5V

+5V

+5V

+5V

+5V

+5V

RST

OSC

OSC

RST

DCLKCSDINBUSYDOUT

U1

IN2

GND

4

OUT6

TEMP3

TRIM5

-5V

+5V

Electronic circuit diagram of the magnetic sensor

Photograph of the completed measuring system data acquisition

software in PC and probe scanning system

Experimental Setup for Magnetic Sensor

Reference material Scanning System Software LabVIEW

Reference Material (1) Normal defects and PVCs

Longitudinal and transverse defects

Def W L D Remarks

1 02 500 0213 (20 ) Inner defects

2 02 500 0427 (40 )

3 02 500 0213 (20 )Outer defectsPVC(1018)4 02 500 0427 (40 )

5 02 500 0639 (60 )

6 02 500 0852 (80 )

7 02 500 0639 (60 ) Inner defects

8 02 500 0852 (80 )

- 1 and 2 are inner defects

- 345 and 6 are outer defects with PVC

- 7 and 8 are inner defects

PVC

PVC

Defect Defect

For longitudinal defects and PVC For circumferential defects and PVC

ECT is very difficult to detect circumferential defects

We can distinguish PVCs and defects and longitudinal and circumferential defects

Flux-gate Magnetometer

One core sensor Two core sensor

3-축 flux-gate Magnetometer의 계략도

Sensorpia Co

pro

cess

or(

AV

R)

Sensor 1

RS422

Interface

Mic

ro-p

roce

ssor(

AV

R)

Sensor 2

Sensor 3

Interface

조립된 마그네토미터의 사진

Sensorpia Co

Analog PCB

Digital PCB

Sensorpia Co선형도(linearity)

10

20

30

40

50

60

y-axis

Magnetometer Output (microT)

-60 -50 -40 -30 -20 -10 0 10 20 30 40 50 60

-60

-50

-40

-30

-20

-10

0

10

Y-axis y=099946 x+0015STD 106E-4

Magnetometer Output (

Applied Magnetic Field (microT)

마그네토미터의 noise 특성 Sensorpia Co

1

10

100

y-axis

Magnetometer noise (nT)

0 1 2 3 4 5 6

1E-4

1E-3

001

01

Magnetometer noise (nT)

Frequency (Hz)

Magnetometer for KoDSAT

-150 -100 -50 0 50 100 150

-15

-10

-5

0

5

10

15

Magnetic Moment (Am

2)

Current (mA)

After Thermal Cycle Test

Measured

Resistance 193 ohm

Photograph of Magnetic torquer

Photograph of KoDSAT

Photograph of

3-axis Fluxgate

Magnetometer

Photograph of Magnetic torquer

Application of magnetometer

Moon magnetic fieldmeasurement

Telescope with direction indication

Joule Effect (Magnetostriction)

ϕ2cosel

l=

∆

0=∆

+∆

+∆

b

b

a

a

l

l

Actuator using Terfenol-D

00

05

10

B (T)

800

1000

1200

1400

1600

Magnetostriction (ppm)

-100 -50 0 50 100

-10

-05

00

B (T)

H (kAm)

2 MPa

4 MPa

6 MPa

8 MPa

10 MPa

12 MPa

-100 -50 0 50 100

-200

0

200

400

600

Magnetostriction (ppm)

H (kAm)

2 MPa

4 MPa

6 MPa

8 MPa

10 MPa

12 MPa

600

700

800

900

1000

-4 -3 -2 -1 0 1 2 3 4

0

10

20

30

40

50

60

Displacement (m

icro meter)

I (A)

FIELD

9 kAm

12 kAm

16 kAm

20 kAm

24 kAm

38 kAm

-50 -40 -30 -20 -10 0 10 20 30 40 50

-100

0

100

200

300

400

500

L (PPM)

H (kAm)

9 kAm

12 kAm

16 kAm

20 kAm

24 kAm

38 kAm

Magnetostrictive displacement sensor

Hysteresis loops under

tensile stress σ

(a) Crystalline 68 NiFe

λs = +25 10-6

(b) crystalline pure Ni λs

= -35 10-6

Villari Effect ( Inverse of Joule Effect)

= -35 10-6

(c) amorphous Co-based

alloy

λs = -35 10-6

ϕσλ 2sin2

3sdotsdot= smeE

γ

Permeability depending on the stress

σλmicromicro

1

3

2

Y

J

so

s

r =

γ

Calculated magnetization curves under stress

Variation of magnetization curve by an applied

tensile force (Co-based amorphous alloy)

Alloy Requirement

Materials for magnetoelastic sensors

Why amorphous magnetic materials are important

Stress-strain curves of several materials

Coercivity and hardness of several materials

Principles of magnetoelastic sensors

Non-contact torque sensor

Principle of cross torductor torque

sensor and flux pattern of sensor

poles on the surface of a shaft

a) without and b)with torsional load

Equivalent magnetic circuit of

cross type torque sensor

Helices of principal tensile and compressive stress on the surface of

a shaft subjected to torsion [32] Correlated changes of permeability

are detected by four-branch yoke system with sensing coils 123

and 4 and a common excitation pole

Examples of torque sensors

Four-branch type torque sensor

heads Pole structures realized

by commercial multi-pole

ferrites 14 and 18 min in

diameter (diameter of sensor

h e a d 1 7 a n d 2 4 m m

respectively) respectively)

Principle of Ring Torductor torque transducer

(a b) Physical structure (c) evolution of the

shaft surface under the transducer poles A and BRing torductor for measuring

torque on ship propeller shafts

(shaft diameter ca 500 mm)

(Courtesy ASEA Brown

Boveri AG)

Principal designs of coaxial torque sensors

Schematic diagram of data processing

electronics of a torque sensor

Extensometer (a) Construction of strain sensing element using

amorphous ribbon wound core (b) configuration of lumped

windings

∆E effect of an amorphous FeNi-based

alloy (Fe40 Ni38 Mo4 B18) Hs saturation

field

Magnetically tunable delay line

Torque Sensors using Amorphous wire

Sixtus tonk효과(large Barkhausen효과)

Hysteresis loops of a Wiegand wire for different reset fields

Curie 온도 및Hopkinson효과

Relation between normalised

saturation polarisation and

normalised Curie temperature

Permeability of a Mn-Zn ferrite as

a function of temperature and field

strength

Conclusions

1) Magnetic sensor 는 자동차 공장자동화 항공우주 및 군사용으로많이 사용되고 있다

2) 새로운 소재개발은 자기센서의 성능개발에 직접적인 영향을 준다2) 새로운 소재개발은 자기센서의 성능개발에 직접적인 영향을 준다

3) 센서의 개발을 위해서는 다양한 전공지식이 요구된다

(물리학 재료공학 기계공학 전자공학)

4) 센서분야가 고부가가치를 창출하는 부품사업이다

5) 핵심부품을 생산하는 중소기업의 item으로도 적절하다

Applications of differential cross-anchor sensors

AC-excited Sensors for Rotary Movements

Principle of construction of a synchro

α cos10 sdotsdot= UKU y

)120-( cos10 degsdotsdot= αUKU z

)240-( cos10 degsdotsdot= αUKU x

)120-( sin3100 degsdotsdotsdot=minus= αKUUUU yxyx

)240-( sin3100 degsdotsdotsdot=minus= αKUUUU zyzy

α sin3100 sdotsdotsdot=minus= KUUUU xzxz

Application to the Torque Sensor

Principle of construction of a torque-type synchro

Torque versus angular

difference

)( sin~ rt αα minussdotKM

)( cos~ rt1r αα minussdotUU

Principle of construction of a control-type sensor

Output voltage versus

angular difference

Principle of construction of a differential sychro

Eddy Current Sensors

tBE dd curl minus=JH = curl

0 div =BH(H)B sdot= micro

E(E)J sdot= σ

A B curl= A B curl=

tdd- A E =

)dd( tAJ minus= σ

tdd curl curl AA σmicro minus=

AA) σωmicro iminus= curl )(curl(1

AA) σωmicro i=∆)((1

Eddy Current Tachometer

Construction of a speedometer (courtesy VDO Adolf Schinding AG) 1) spindle 2) bearing

3) holding spring 4) iron yoke 5) eddy current cup 6) shaft of the magnet 7) support of

the magnet 8) temperature compensation 9) permanent magnet 10) torsion spring

Proximity Sensors

Schematic diagram of a proximity sensor

Output current of a proximity switch versus distance

Inductive Flowmeters

)( Btimessdot= υqF

EqF sdot=BE times=υ

)(ds Btimes== υEU )(ds Btimes== υEU

)( Bd timessdot= υU

Bsdotsdotsdot= υdKU

Development of magnetic phase detection

sensor for steam generator tube

Dirac Son1 Kwan-Sang Ryu2 Duck-Gun Park3

1Hannam University Daejeon Rep of Korea2Korea Research Institute of Standards and Science Daejeon Rep of Korea3KoreaAtomic Energy Research Institute Daejeon Rep of Korea

Introduction

The layout of pressurized water reactor (PWR) components

Primary side Secondary side (non-radioactive side)(radioactive side)

The Structure of SG(Steam Generator)(degradation mechanism)

Secondary SidePrimary Side

SCC

A B

A-B

Steam outlet

Anti-vibration

SCC

Fretting

Wall thinning

IGA

U-bend

In commercial power plants SG- height up to 21 m - weight up to 800 tons - 2~4 sets of SG were installed - SG can contain from 3000 to

16000 tubes each about 20 mmin diameter

Primary coolant outlet Primary coolant inlet

Anti-vibrationbars

Tubesupportplate

Tubesheet

IGA

SCC

Pitting

SCC

Inside Tubesheet

Top of Tubesheet

by SSHwang of KAERI

Denting

Sludge pile

in diameter

The SGT is made of nickel basedInconel alloy which is composed of 75 Ni 165Cr and 815Fe

-Degradation mechanism corrosion pitting denting inter granular attack

-Inspection Eddy current Testing(ECT)

Permeability Variation Clusters (PVC)

(Ferro-magnetic phase)

-005

000

005

010

015

m (emug)

1-1

-002

000

002

004

006

008

m (emug)

1-2

-1000 -500 0 500 1000

-015

-010

-005

H ( Am )

-1000 -500 0 500 1000

-006

-004

-002

H ( Am )

The hystresis loop in the fragment of PVC parts of Kori-1 retired SG tube

-004

-002

000

002

004

006

M (emug)

Inconel 600 tested at RT

under tensile stress

1 2 3

4 5 6

7 8 9-004

-002

000

002

004

006

M(emug)

Inconel 600 Heat treated at

602 oC under tensile stress

1 2 3

How can we detect magnetic phase

(PVC)selectively from the flaws in SGT

-3000 -2000 -1000 0 1000 2000 3000

-006

H (Oe)

7 8 9

10 11 12

-3000 -2000 -1000 0 1000 2000 3000

-006

-004

H(Oe)

4 5 6

7 8 9

The hysteresis loop of the tensile tested specimen at room temperature (a) and tensile tested at high temperature (b)

The magnetic phase can be created under the high temperature andpressure conditions which is correspond to the stress corrosion crackingin the SG tube in the NPP(Bruemmer SM Charlot LA amp Henager CH (1988) Corrosion 782)

Principle of ECT

If we can separate magnetic phase selectively from the

flaws using magnetic sensor the reliability of EC in SGT

inspection will be greatly enhanced

Structure of the permeability

sensor

Dimension and photograph of U-shape

sensing yoke

Design of Magnetic Sensor for PVC

sensor sensing yoke

Photograph of the completed sensor front side (above) and rear side (bottom)

R11R12

R10

R8

R6

R9

R13

R7

R14

C18

1 n

C17

C20

C21

D2

DIODE

SIN COS

-

+

U-2A

4

13

2

-

+

U-2B

75

6

8

-

+

U-3A

13

2

8

+5VC19

104

+5V

Schematic diagram of the sensor system

Electronic Circuit of Magnetic Sensor

R20

R

R21

R

-

+

U5AD797

3

26

74

U6

D1

S12

GND3

+VCC4VCC5

IN6

-VCC7

S28

C41

R13

R26

R18

R25

R2210 Ω

R16

R14

R17

10 k

R15

R27

R32

R28

R33

R29

R34

5 k

R30

C29

C37

104

C32473

C39473C40

104

C33

104

C21

104C23

104

C25

104

C26

104

C30

104

C31

104

C35

104

C36

104

C27

104

C28

104

C34

104

C38

104

D3

DIODE

L1

1

2

L2

1

2

L3

1

2

4

-

+

U-4A

4

13

2

-

+

U-4B

75

6

8

-

+

U-5A

4

13

2

-

+

U-5B

75

6

8

-

+

U-6A

4

13

2

-

+

U-6B

75

6

8

C22

104

-5V

+5V

+5V

+5V

+5V

+5V

+5V

U7

D1

S12

GND3

+VCC4

VCC5

IN6

-VCC7

S28

+5V

-5V

-5V

-5V

-5V

-5V

-5V

-5V

-5V

R19

R24

R

R23

R

C24

OUT(X)

OUT(Y)

R1

20 kR210 k

R3

20 kR410 k

C1

104

C8

104

REF43

OUT(X)

OUT(Y)

REF43

U2

+Vcc1

CH02

CH13

CH24

CH35

COMM6

SHDN7

Vref8

+Vcc9

GND10

GND11

DOUT12BUSY13DIN14CS15

DIN16

-

+

U-1A

13

2

8

-

+

U-1B

4

75

6

C410 uF

C5104

DOUT

C210uF

C6104

C3104

DCLK

C7104

DIN

C10

01uF

CS

BUSY

C14 10uF

J1

CON6

123456

D1

DIODE

R5

47K

C9

10uF

C1310uF

Y1

OSC

OUT3

GND2

VCC4

U3

RSTVPP1

GND10

VCC20

XTAL15

XTAL24

P10AIN012P11AIN113P1214P1315P1416P1517P1618P1719

P30RXD2

P31TXD3

P32INT06

P33INT17

P34T08

P35T19

P3711

U4

C1+1

C1-3

C2+4

C2-5

VCC16

GND15

V+2

V-6

R1OUT12

R2OUT9

T1IN11

T2IN10

R1IN13

R2IN8

T1OUT14

T2OUT7

C12 10uF

C16

01uF

C15 10uF

C11

01uF

-5V

+5V

+5V

+5V

+5V

+5V

+5V

+5V

RST

OSC

OSC

RST

DCLKCSDINBUSYDOUT

U1

IN2

GND

4

OUT6

TEMP3

TRIM5

-5V

+5V

Electronic circuit diagram of the magnetic sensor

Photograph of the completed measuring system data acquisition

software in PC and probe scanning system

Experimental Setup for Magnetic Sensor

Reference material Scanning System Software LabVIEW

Reference Material (1) Normal defects and PVCs

Longitudinal and transverse defects

Def W L D Remarks

1 02 500 0213 (20 ) Inner defects

2 02 500 0427 (40 )

3 02 500 0213 (20 )Outer defectsPVC(1018)4 02 500 0427 (40 )

5 02 500 0639 (60 )

6 02 500 0852 (80 )

7 02 500 0639 (60 ) Inner defects

8 02 500 0852 (80 )

- 1 and 2 are inner defects

- 345 and 6 are outer defects with PVC

- 7 and 8 are inner defects

PVC

PVC

Defect Defect

For longitudinal defects and PVC For circumferential defects and PVC

ECT is very difficult to detect circumferential defects

We can distinguish PVCs and defects and longitudinal and circumferential defects

Flux-gate Magnetometer

One core sensor Two core sensor

3-축 flux-gate Magnetometer의 계략도

Sensorpia Co

pro

cess

or(

AV

R)

Sensor 1

RS422

Interface

Mic

ro-p

roce

ssor(

AV

R)

Sensor 2

Sensor 3

Interface

조립된 마그네토미터의 사진

Sensorpia Co

Analog PCB

Digital PCB

Sensorpia Co선형도(linearity)

10

20

30

40

50

60

y-axis

Magnetometer Output (microT)

-60 -50 -40 -30 -20 -10 0 10 20 30 40 50 60

-60

-50

-40

-30

-20

-10

0

10

Y-axis y=099946 x+0015STD 106E-4

Magnetometer Output (

Applied Magnetic Field (microT)

마그네토미터의 noise 특성 Sensorpia Co

1

10

100

y-axis

Magnetometer noise (nT)

0 1 2 3 4 5 6

1E-4

1E-3

001

01

Magnetometer noise (nT)

Frequency (Hz)

Magnetometer for KoDSAT

-150 -100 -50 0 50 100 150

-15

-10

-5

0

5

10

15

Magnetic Moment (Am

2)

Current (mA)

After Thermal Cycle Test

Measured

Resistance 193 ohm

Photograph of Magnetic torquer

Photograph of KoDSAT

Photograph of

3-axis Fluxgate

Magnetometer

Photograph of Magnetic torquer

Application of magnetometer

Moon magnetic fieldmeasurement

Telescope with direction indication

Joule Effect (Magnetostriction)

ϕ2cosel

l=

∆

0=∆

+∆

+∆

b

b

a

a

l

l

Actuator using Terfenol-D

00

05

10

B (T)

800

1000

1200

1400

1600

Magnetostriction (ppm)

-100 -50 0 50 100

-10

-05

00

B (T)

H (kAm)

2 MPa

4 MPa

6 MPa

8 MPa

10 MPa

12 MPa

-100 -50 0 50 100

-200

0

200

400

600

Magnetostriction (ppm)

H (kAm)

2 MPa

4 MPa

6 MPa

8 MPa

10 MPa

12 MPa

600

700

800

900

1000

-4 -3 -2 -1 0 1 2 3 4

0

10

20

30

40

50

60

Displacement (m

icro meter)

I (A)

FIELD

9 kAm

12 kAm

16 kAm

20 kAm

24 kAm

38 kAm

-50 -40 -30 -20 -10 0 10 20 30 40 50

-100

0

100

200

300

400

500

L (PPM)

H (kAm)

9 kAm

12 kAm

16 kAm

20 kAm

24 kAm

38 kAm

Magnetostrictive displacement sensor

Hysteresis loops under

tensile stress σ

(a) Crystalline 68 NiFe

λs = +25 10-6

(b) crystalline pure Ni λs

= -35 10-6

Villari Effect ( Inverse of Joule Effect)

= -35 10-6

(c) amorphous Co-based

alloy

λs = -35 10-6

ϕσλ 2sin2

3sdotsdot= smeE

γ

Permeability depending on the stress

σλmicromicro

1

3

2

Y

J

so

s

r =

γ

Calculated magnetization curves under stress

Variation of magnetization curve by an applied

tensile force (Co-based amorphous alloy)

Alloy Requirement

Materials for magnetoelastic sensors

Why amorphous magnetic materials are important

Stress-strain curves of several materials

Coercivity and hardness of several materials

Principles of magnetoelastic sensors

Non-contact torque sensor

Principle of cross torductor torque

sensor and flux pattern of sensor

poles on the surface of a shaft

a) without and b)with torsional load

Equivalent magnetic circuit of

cross type torque sensor

Helices of principal tensile and compressive stress on the surface of

a shaft subjected to torsion [32] Correlated changes of permeability

are detected by four-branch yoke system with sensing coils 123

and 4 and a common excitation pole

Examples of torque sensors

Four-branch type torque sensor

heads Pole structures realized

by commercial multi-pole

ferrites 14 and 18 min in

diameter (diameter of sensor

h e a d 1 7 a n d 2 4 m m

respectively) respectively)

Principle of Ring Torductor torque transducer

(a b) Physical structure (c) evolution of the

shaft surface under the transducer poles A and BRing torductor for measuring

torque on ship propeller shafts

(shaft diameter ca 500 mm)

(Courtesy ASEA Brown

Boveri AG)

Principal designs of coaxial torque sensors

Schematic diagram of data processing

electronics of a torque sensor

Extensometer (a) Construction of strain sensing element using

amorphous ribbon wound core (b) configuration of lumped

windings

∆E effect of an amorphous FeNi-based

alloy (Fe40 Ni38 Mo4 B18) Hs saturation

field

Magnetically tunable delay line

Torque Sensors using Amorphous wire

Sixtus tonk효과(large Barkhausen효과)

Hysteresis loops of a Wiegand wire for different reset fields

Curie 온도 및Hopkinson효과

Relation between normalised

saturation polarisation and

normalised Curie temperature

Permeability of a Mn-Zn ferrite as

a function of temperature and field

strength

Conclusions

1) Magnetic sensor 는 자동차 공장자동화 항공우주 및 군사용으로많이 사용되고 있다

2) 새로운 소재개발은 자기센서의 성능개발에 직접적인 영향을 준다2) 새로운 소재개발은 자기센서의 성능개발에 직접적인 영향을 준다

3) 센서의 개발을 위해서는 다양한 전공지식이 요구된다

(물리학 재료공학 기계공학 전자공학)

4) 센서분야가 고부가가치를 창출하는 부품사업이다

5) 핵심부품을 생산하는 중소기업의 item으로도 적절하다

AC-excited Sensors for Rotary Movements

Principle of construction of a synchro

α cos10 sdotsdot= UKU y

)120-( cos10 degsdotsdot= αUKU z

)240-( cos10 degsdotsdot= αUKU x

)120-( sin3100 degsdotsdotsdot=minus= αKUUUU yxyx

)240-( sin3100 degsdotsdotsdot=minus= αKUUUU zyzy

α sin3100 sdotsdotsdot=minus= KUUUU xzxz

Application to the Torque Sensor

Principle of construction of a torque-type synchro

Torque versus angular

difference

)( sin~ rt αα minussdotKM

)( cos~ rt1r αα minussdotUU

Principle of construction of a control-type sensor

Output voltage versus

angular difference

Principle of construction of a differential sychro

Eddy Current Sensors

tBE dd curl minus=JH = curl

0 div =BH(H)B sdot= micro

E(E)J sdot= σ

A B curl= A B curl=

tdd- A E =

)dd( tAJ minus= σ

tdd curl curl AA σmicro minus=

AA) σωmicro iminus= curl )(curl(1

AA) σωmicro i=∆)((1

Eddy Current Tachometer

Construction of a speedometer (courtesy VDO Adolf Schinding AG) 1) spindle 2) bearing

3) holding spring 4) iron yoke 5) eddy current cup 6) shaft of the magnet 7) support of

the magnet 8) temperature compensation 9) permanent magnet 10) torsion spring

Proximity Sensors

Schematic diagram of a proximity sensor

Output current of a proximity switch versus distance

Inductive Flowmeters

)( Btimessdot= υqF

EqF sdot=BE times=υ

)(ds Btimes== υEU )(ds Btimes== υEU

)( Bd timessdot= υU

Bsdotsdotsdot= υdKU

Development of magnetic phase detection

sensor for steam generator tube

Dirac Son1 Kwan-Sang Ryu2 Duck-Gun Park3

1Hannam University Daejeon Rep of Korea2Korea Research Institute of Standards and Science Daejeon Rep of Korea3KoreaAtomic Energy Research Institute Daejeon Rep of Korea

Introduction

The layout of pressurized water reactor (PWR) components

Primary side Secondary side (non-radioactive side)(radioactive side)

The Structure of SG(Steam Generator)(degradation mechanism)

Secondary SidePrimary Side

SCC

A B

A-B

Steam outlet

Anti-vibration

SCC

Fretting

Wall thinning

IGA

U-bend

In commercial power plants SG- height up to 21 m - weight up to 800 tons - 2~4 sets of SG were installed - SG can contain from 3000 to

16000 tubes each about 20 mmin diameter

Primary coolant outlet Primary coolant inlet

Anti-vibrationbars

Tubesupportplate

Tubesheet

IGA

SCC

Pitting

SCC

Inside Tubesheet

Top of Tubesheet

by SSHwang of KAERI

Denting

Sludge pile

in diameter

The SGT is made of nickel basedInconel alloy which is composed of 75 Ni 165Cr and 815Fe

-Degradation mechanism corrosion pitting denting inter granular attack

-Inspection Eddy current Testing(ECT)

Permeability Variation Clusters (PVC)

(Ferro-magnetic phase)

-005

000

005

010

015

m (emug)

1-1

-002

000

002

004

006

008

m (emug)

1-2

-1000 -500 0 500 1000

-015

-010

-005

H ( Am )

-1000 -500 0 500 1000

-006

-004

-002

H ( Am )

The hystresis loop in the fragment of PVC parts of Kori-1 retired SG tube

-004

-002

000

002

004

006

M (emug)

Inconel 600 tested at RT

under tensile stress

1 2 3

4 5 6

7 8 9-004

-002

000

002

004

006

M(emug)

Inconel 600 Heat treated at

602 oC under tensile stress

1 2 3

How can we detect magnetic phase

(PVC)selectively from the flaws in SGT

-3000 -2000 -1000 0 1000 2000 3000

-006

H (Oe)

7 8 9

10 11 12

-3000 -2000 -1000 0 1000 2000 3000

-006

-004

H(Oe)

4 5 6

7 8 9

The hysteresis loop of the tensile tested specimen at room temperature (a) and tensile tested at high temperature (b)

The magnetic phase can be created under the high temperature andpressure conditions which is correspond to the stress corrosion crackingin the SG tube in the NPP(Bruemmer SM Charlot LA amp Henager CH (1988) Corrosion 782)

Principle of ECT

If we can separate magnetic phase selectively from the

flaws using magnetic sensor the reliability of EC in SGT

inspection will be greatly enhanced

Structure of the permeability

sensor

Dimension and photograph of U-shape

sensing yoke

Design of Magnetic Sensor for PVC

sensor sensing yoke

Photograph of the completed sensor front side (above) and rear side (bottom)

R11R12

R10

R8

R6

R9

R13

R7

R14

C18

1 n

C17

C20

C21

D2

DIODE

SIN COS

-

+

U-2A

4

13

2

-

+

U-2B

75

6

8

-

+

U-3A

13

2

8

+5VC19

104

+5V

Schematic diagram of the sensor system

Electronic Circuit of Magnetic Sensor

R20

R

R21

R

-

+

U5AD797

3

26

74

U6

D1

S12

GND3

+VCC4VCC5

IN6

-VCC7

S28

C41

R13

R26

R18

R25

R2210 Ω

R16

R14

R17

10 k

R15

R27

R32

R28

R33

R29

R34

5 k

R30

C29

C37

104

C32473

C39473C40

104

C33

104

C21

104C23

104

C25

104

C26

104

C30

104

C31

104

C35

104

C36

104

C27

104

C28

104

C34

104

C38

104

D3

DIODE

L1

1

2

L2

1

2

L3

1

2

4

-

+

U-4A

4

13

2

-

+

U-4B

75

6

8

-

+

U-5A

4

13

2

-

+

U-5B

75

6

8

-

+

U-6A

4

13

2

-

+

U-6B

75

6

8

C22

104

-5V

+5V

+5V

+5V

+5V

+5V

+5V

U7

D1

S12

GND3

+VCC4

VCC5

IN6

-VCC7

S28

+5V

-5V

-5V

-5V

-5V

-5V

-5V

-5V

-5V

R19

R24

R

R23

R

C24

OUT(X)

OUT(Y)

R1

20 kR210 k

R3

20 kR410 k

C1

104

C8

104

REF43

OUT(X)

OUT(Y)

REF43

U2

+Vcc1

CH02

CH13

CH24

CH35

COMM6

SHDN7

Vref8

+Vcc9

GND10

GND11

DOUT12BUSY13DIN14CS15

DIN16

-

+

U-1A

13

2

8

-

+

U-1B

4

75

6

C410 uF

C5104

DOUT

C210uF

C6104

C3104

DCLK

C7104

DIN

C10

01uF

CS

BUSY

C14 10uF

J1

CON6

123456

D1

DIODE

R5

47K

C9

10uF

C1310uF

Y1

OSC

OUT3

GND2

VCC4

U3

RSTVPP1

GND10

VCC20

XTAL15

XTAL24

P10AIN012P11AIN113P1214P1315P1416P1517P1618P1719

P30RXD2

P31TXD3

P32INT06

P33INT17

P34T08

P35T19

P3711

U4

C1+1

C1-3

C2+4

C2-5

VCC16

GND15

V+2

V-6

R1OUT12

R2OUT9

T1IN11

T2IN10

R1IN13

R2IN8

T1OUT14

T2OUT7

C12 10uF

C16

01uF

C15 10uF

C11

01uF

-5V

+5V

+5V

+5V

+5V

+5V

+5V

+5V

RST

OSC

OSC

RST

DCLKCSDINBUSYDOUT

U1

IN2

GND

4

OUT6

TEMP3

TRIM5

-5V

+5V

Electronic circuit diagram of the magnetic sensor

Photograph of the completed measuring system data acquisition

software in PC and probe scanning system

Experimental Setup for Magnetic Sensor

Reference material Scanning System Software LabVIEW

Reference Material (1) Normal defects and PVCs

Longitudinal and transverse defects

Def W L D Remarks

1 02 500 0213 (20 ) Inner defects

2 02 500 0427 (40 )

3 02 500 0213 (20 )Outer defectsPVC(1018)4 02 500 0427 (40 )

5 02 500 0639 (60 )

6 02 500 0852 (80 )

7 02 500 0639 (60 ) Inner defects

8 02 500 0852 (80 )

- 1 and 2 are inner defects

- 345 and 6 are outer defects with PVC

- 7 and 8 are inner defects

PVC

PVC

Defect Defect

For longitudinal defects and PVC For circumferential defects and PVC

ECT is very difficult to detect circumferential defects

We can distinguish PVCs and defects and longitudinal and circumferential defects

Flux-gate Magnetometer

One core sensor Two core sensor

3-축 flux-gate Magnetometer의 계략도

Sensorpia Co

pro

cess

or(

AV

R)

Sensor 1

RS422

Interface

Mic

ro-p

roce

ssor(

AV

R)

Sensor 2

Sensor 3

Interface

조립된 마그네토미터의 사진

Sensorpia Co

Analog PCB

Digital PCB

Sensorpia Co선형도(linearity)

10

20

30

40

50

60

y-axis

Magnetometer Output (microT)

-60 -50 -40 -30 -20 -10 0 10 20 30 40 50 60

-60

-50

-40

-30

-20

-10

0

10

Y-axis y=099946 x+0015STD 106E-4

Magnetometer Output (

Applied Magnetic Field (microT)

마그네토미터의 noise 특성 Sensorpia Co

1

10

100

y-axis

Magnetometer noise (nT)

0 1 2 3 4 5 6

1E-4

1E-3

001

01

Magnetometer noise (nT)

Frequency (Hz)

Magnetometer for KoDSAT

-150 -100 -50 0 50 100 150

-15

-10

-5

0

5

10

15

Magnetic Moment (Am

2)

Current (mA)

After Thermal Cycle Test

Measured

Resistance 193 ohm

Photograph of Magnetic torquer

Photograph of KoDSAT

Photograph of

3-axis Fluxgate

Magnetometer

Photograph of Magnetic torquer

Application of magnetometer

Moon magnetic fieldmeasurement

Telescope with direction indication

Joule Effect (Magnetostriction)

ϕ2cosel

l=

∆

0=∆

+∆

+∆

b

b

a

a

l

l

Actuator using Terfenol-D

00

05

10

B (T)

800

1000

1200

1400

1600

Magnetostriction (ppm)

-100 -50 0 50 100

-10

-05

00

B (T)

H (kAm)

2 MPa

4 MPa

6 MPa

8 MPa

10 MPa

12 MPa

-100 -50 0 50 100

-200

0

200

400

600

Magnetostriction (ppm)

H (kAm)

2 MPa

4 MPa

6 MPa

8 MPa

10 MPa

12 MPa

600

700

800

900

1000

-4 -3 -2 -1 0 1 2 3 4

0

10

20

30

40

50

60

Displacement (m

icro meter)

I (A)

FIELD

9 kAm

12 kAm

16 kAm

20 kAm

24 kAm

38 kAm

-50 -40 -30 -20 -10 0 10 20 30 40 50

-100

0

100

200

300

400

500

L (PPM)

H (kAm)

9 kAm

12 kAm

16 kAm

20 kAm

24 kAm

38 kAm

Magnetostrictive displacement sensor

Hysteresis loops under

tensile stress σ

(a) Crystalline 68 NiFe

λs = +25 10-6

(b) crystalline pure Ni λs

= -35 10-6

Villari Effect ( Inverse of Joule Effect)

= -35 10-6

(c) amorphous Co-based

alloy

λs = -35 10-6

ϕσλ 2sin2

3sdotsdot= smeE

γ

Permeability depending on the stress

σλmicromicro

1

3

2

Y

J

so

s

r =

γ

Calculated magnetization curves under stress

Variation of magnetization curve by an applied

tensile force (Co-based amorphous alloy)

Alloy Requirement

Materials for magnetoelastic sensors

Why amorphous magnetic materials are important

Stress-strain curves of several materials

Coercivity and hardness of several materials

Principles of magnetoelastic sensors

Non-contact torque sensor

Principle of cross torductor torque

sensor and flux pattern of sensor

poles on the surface of a shaft

a) without and b)with torsional load

Equivalent magnetic circuit of

cross type torque sensor

Helices of principal tensile and compressive stress on the surface of

a shaft subjected to torsion [32] Correlated changes of permeability

are detected by four-branch yoke system with sensing coils 123

and 4 and a common excitation pole

Examples of torque sensors

Four-branch type torque sensor

heads Pole structures realized

by commercial multi-pole

ferrites 14 and 18 min in

diameter (diameter of sensor

h e a d 1 7 a n d 2 4 m m

respectively) respectively)

Principle of Ring Torductor torque transducer

(a b) Physical structure (c) evolution of the

shaft surface under the transducer poles A and BRing torductor for measuring

torque on ship propeller shafts

(shaft diameter ca 500 mm)

(Courtesy ASEA Brown

Boveri AG)

Principal designs of coaxial torque sensors

Schematic diagram of data processing

electronics of a torque sensor

Extensometer (a) Construction of strain sensing element using

amorphous ribbon wound core (b) configuration of lumped

windings

∆E effect of an amorphous FeNi-based

alloy (Fe40 Ni38 Mo4 B18) Hs saturation

field

Magnetically tunable delay line

Torque Sensors using Amorphous wire

Sixtus tonk효과(large Barkhausen효과)

Hysteresis loops of a Wiegand wire for different reset fields

Curie 온도 및Hopkinson효과

Relation between normalised

saturation polarisation and

normalised Curie temperature

Permeability of a Mn-Zn ferrite as

a function of temperature and field

strength

Conclusions

1) Magnetic sensor 는 자동차 공장자동화 항공우주 및 군사용으로많이 사용되고 있다

2) 새로운 소재개발은 자기센서의 성능개발에 직접적인 영향을 준다2) 새로운 소재개발은 자기센서의 성능개발에 직접적인 영향을 준다

3) 센서의 개발을 위해서는 다양한 전공지식이 요구된다

(물리학 재료공학 기계공학 전자공학)

4) 센서분야가 고부가가치를 창출하는 부품사업이다

5) 핵심부품을 생산하는 중소기업의 item으로도 적절하다

Application to the Torque Sensor

Principle of construction of a torque-type synchro

Torque versus angular

difference

)( sin~ rt αα minussdotKM

)( cos~ rt1r αα minussdotUU

Principle of construction of a control-type sensor

Output voltage versus

angular difference

Principle of construction of a differential sychro

Eddy Current Sensors

tBE dd curl minus=JH = curl

0 div =BH(H)B sdot= micro

E(E)J sdot= σ

A B curl= A B curl=

tdd- A E =

)dd( tAJ minus= σ

tdd curl curl AA σmicro minus=

AA) σωmicro iminus= curl )(curl(1

AA) σωmicro i=∆)((1

Eddy Current Tachometer

Construction of a speedometer (courtesy VDO Adolf Schinding AG) 1) spindle 2) bearing

3) holding spring 4) iron yoke 5) eddy current cup 6) shaft of the magnet 7) support of

the magnet 8) temperature compensation 9) permanent magnet 10) torsion spring

Proximity Sensors

Schematic diagram of a proximity sensor

Output current of a proximity switch versus distance

Inductive Flowmeters

)( Btimessdot= υqF

EqF sdot=BE times=υ

)(ds Btimes== υEU )(ds Btimes== υEU

)( Bd timessdot= υU

Bsdotsdotsdot= υdKU

Development of magnetic phase detection

sensor for steam generator tube

Dirac Son1 Kwan-Sang Ryu2 Duck-Gun Park3

1Hannam University Daejeon Rep of Korea2Korea Research Institute of Standards and Science Daejeon Rep of Korea3KoreaAtomic Energy Research Institute Daejeon Rep of Korea

Introduction

The layout of pressurized water reactor (PWR) components

Primary side Secondary side (non-radioactive side)(radioactive side)

The Structure of SG(Steam Generator)(degradation mechanism)

Secondary SidePrimary Side

SCC

A B

A-B

Steam outlet

Anti-vibration

SCC

Fretting

Wall thinning

IGA

U-bend

In commercial power plants SG- height up to 21 m - weight up to 800 tons - 2~4 sets of SG were installed - SG can contain from 3000 to

16000 tubes each about 20 mmin diameter

Primary coolant outlet Primary coolant inlet

Anti-vibrationbars

Tubesupportplate

Tubesheet

IGA

SCC

Pitting

SCC

Inside Tubesheet

Top of Tubesheet

by SSHwang of KAERI

Denting

Sludge pile

in diameter

The SGT is made of nickel basedInconel alloy which is composed of 75 Ni 165Cr and 815Fe

-Degradation mechanism corrosion pitting denting inter granular attack

-Inspection Eddy current Testing(ECT)

Permeability Variation Clusters (PVC)

(Ferro-magnetic phase)

-005

000

005

010

015

m (emug)

1-1

-002

000

002

004

006

008

m (emug)

1-2

-1000 -500 0 500 1000

-015

-010

-005

H ( Am )

-1000 -500 0 500 1000

-006

-004

-002

H ( Am )

The hystresis loop in the fragment of PVC parts of Kori-1 retired SG tube

-004

-002

000

002

004

006

M (emug)

Inconel 600 tested at RT

under tensile stress

1 2 3

4 5 6

7 8 9-004

-002

000

002

004

006

M(emug)

Inconel 600 Heat treated at

602 oC under tensile stress

1 2 3

How can we detect magnetic phase

(PVC)selectively from the flaws in SGT

-3000 -2000 -1000 0 1000 2000 3000

-006

H (Oe)

7 8 9

10 11 12

-3000 -2000 -1000 0 1000 2000 3000

-006

-004

H(Oe)

4 5 6

7 8 9

The hysteresis loop of the tensile tested specimen at room temperature (a) and tensile tested at high temperature (b)

The magnetic phase can be created under the high temperature andpressure conditions which is correspond to the stress corrosion crackingin the SG tube in the NPP(Bruemmer SM Charlot LA amp Henager CH (1988) Corrosion 782)

Principle of ECT

If we can separate magnetic phase selectively from the

flaws using magnetic sensor the reliability of EC in SGT

inspection will be greatly enhanced

Structure of the permeability

sensor

Dimension and photograph of U-shape

sensing yoke

Design of Magnetic Sensor for PVC

sensor sensing yoke

Photograph of the completed sensor front side (above) and rear side (bottom)

R11R12

R10

R8

R6

R9

R13

R7

R14

C18

1 n

C17

C20

C21

D2

DIODE

SIN COS

-

+

U-2A

4

13

2

-

+

U-2B

75

6

8

-

+

U-3A

13

2

8

+5VC19

104

+5V

Schematic diagram of the sensor system

Electronic Circuit of Magnetic Sensor

R20

R

R21

R

-

+

U5AD797

3

26

74

U6

D1

S12

GND3

+VCC4VCC5

IN6

-VCC7

S28

C41

R13

R26

R18

R25

R2210 Ω

R16

R14

R17

10 k

R15

R27

R32

R28

R33

R29

R34

5 k

R30

C29

C37

104

C32473

C39473C40

104

C33

104

C21

104C23

104

C25

104

C26

104

C30

104

C31

104

C35

104

C36

104

C27

104

C28

104

C34

104

C38

104

D3

DIODE

L1

1

2

L2

1

2

L3

1

2

4

-

+

U-4A

4

13

2

-

+

U-4B

75

6

8

-

+

U-5A

4

13

2

-

+

U-5B

75

6

8

-

+

U-6A

4

13

2

-

+

U-6B

75

6

8

C22

104

-5V

+5V

+5V

+5V

+5V

+5V

+5V

U7

D1

S12

GND3

+VCC4

VCC5

IN6

-VCC7

S28

+5V

-5V

-5V

-5V

-5V

-5V

-5V

-5V

-5V

R19

R24

R

R23

R

C24

OUT(X)

OUT(Y)

R1

20 kR210 k

R3

20 kR410 k

C1

104

C8

104

REF43

OUT(X)

OUT(Y)

REF43

U2

+Vcc1

CH02

CH13

CH24

CH35

COMM6

SHDN7

Vref8

+Vcc9

GND10

GND11

DOUT12BUSY13DIN14CS15

DIN16

-

+

U-1A

13

2

8

-

+

U-1B

4

75

6

C410 uF

C5104

DOUT

C210uF

C6104

C3104

DCLK

C7104

DIN

C10

01uF

CS

BUSY

C14 10uF

J1

CON6

123456

D1

DIODE

R5

47K

C9

10uF

C1310uF

Y1

OSC

OUT3

GND2

VCC4

U3

RSTVPP1

GND10

VCC20

XTAL15

XTAL24

P10AIN012P11AIN113P1214P1315P1416P1517P1618P1719

P30RXD2

P31TXD3

P32INT06

P33INT17

P34T08

P35T19

P3711

U4

C1+1

C1-3

C2+4

C2-5

VCC16

GND15

V+2

V-6

R1OUT12

R2OUT9

T1IN11

T2IN10

R1IN13

R2IN8

T1OUT14

T2OUT7

C12 10uF

C16

01uF

C15 10uF

C11

01uF

-5V

+5V

+5V

+5V

+5V

+5V

+5V

+5V

RST

OSC

OSC

RST

DCLKCSDINBUSYDOUT

U1

IN2

GND

4

OUT6

TEMP3

TRIM5

-5V

+5V

Electronic circuit diagram of the magnetic sensor

Photograph of the completed measuring system data acquisition

software in PC and probe scanning system

Experimental Setup for Magnetic Sensor

Reference material Scanning System Software LabVIEW

Reference Material (1) Normal defects and PVCs

Longitudinal and transverse defects

Def W L D Remarks

1 02 500 0213 (20 ) Inner defects

2 02 500 0427 (40 )

3 02 500 0213 (20 )Outer defectsPVC(1018)4 02 500 0427 (40 )

5 02 500 0639 (60 )

6 02 500 0852 (80 )

7 02 500 0639 (60 ) Inner defects

8 02 500 0852 (80 )

- 1 and 2 are inner defects

- 345 and 6 are outer defects with PVC

- 7 and 8 are inner defects

PVC

PVC

Defect Defect

For longitudinal defects and PVC For circumferential defects and PVC

ECT is very difficult to detect circumferential defects

We can distinguish PVCs and defects and longitudinal and circumferential defects

Flux-gate Magnetometer

One core sensor Two core sensor

3-축 flux-gate Magnetometer의 계략도

Sensorpia Co

pro

cess

or(

AV

R)

Sensor 1

RS422

Interface

Mic

ro-p

roce

ssor(

AV

R)

Sensor 2

Sensor 3

Interface

조립된 마그네토미터의 사진

Sensorpia Co

Analog PCB

Digital PCB

Sensorpia Co선형도(linearity)

10

20

30

40

50

60

y-axis

Magnetometer Output (microT)

-60 -50 -40 -30 -20 -10 0 10 20 30 40 50 60

-60

-50

-40

-30

-20

-10

0

10

Y-axis y=099946 x+0015STD 106E-4

Magnetometer Output (

Applied Magnetic Field (microT)

마그네토미터의 noise 특성 Sensorpia Co

1

10

100

y-axis

Magnetometer noise (nT)

0 1 2 3 4 5 6

1E-4

1E-3

001

01

Magnetometer noise (nT)

Frequency (Hz)

Magnetometer for KoDSAT

-150 -100 -50 0 50 100 150

-15

-10

-5

0

5

10

15

Magnetic Moment (Am

2)

Current (mA)

After Thermal Cycle Test

Measured

Resistance 193 ohm

Photograph of Magnetic torquer

Photograph of KoDSAT

Photograph of

3-axis Fluxgate

Magnetometer

Photograph of Magnetic torquer

Application of magnetometer

Moon magnetic fieldmeasurement

Telescope with direction indication

Joule Effect (Magnetostriction)

ϕ2cosel

l=

∆

0=∆

+∆

+∆

b

b

a

a

l

l

Actuator using Terfenol-D

00

05

10

B (T)

800

1000

1200

1400

1600

Magnetostriction (ppm)

-100 -50 0 50 100

-10

-05

00

B (T)

H (kAm)

2 MPa

4 MPa

6 MPa

8 MPa

10 MPa

12 MPa

-100 -50 0 50 100

-200

0

200

400

600

Magnetostriction (ppm)

H (kAm)

2 MPa

4 MPa

6 MPa

8 MPa

10 MPa

12 MPa

600

700

800

900

1000

-4 -3 -2 -1 0 1 2 3 4

0

10

20

30

40

50

60

Displacement (m

icro meter)

I (A)

FIELD

9 kAm

12 kAm

16 kAm

20 kAm

24 kAm

38 kAm

-50 -40 -30 -20 -10 0 10 20 30 40 50

-100

0

100

200

300

400

500

L (PPM)

H (kAm)

9 kAm

12 kAm

16 kAm

20 kAm

24 kAm

38 kAm

Magnetostrictive displacement sensor

Hysteresis loops under

tensile stress σ

(a) Crystalline 68 NiFe

λs = +25 10-6

(b) crystalline pure Ni λs

= -35 10-6

Villari Effect ( Inverse of Joule Effect)

= -35 10-6

(c) amorphous Co-based

alloy

λs = -35 10-6

ϕσλ 2sin2

3sdotsdot= smeE

γ

Permeability depending on the stress

σλmicromicro

1

3

2

Y

J

so

s

r =

γ

Calculated magnetization curves under stress

Variation of magnetization curve by an applied

tensile force (Co-based amorphous alloy)

Alloy Requirement

Materials for magnetoelastic sensors

Why amorphous magnetic materials are important

Stress-strain curves of several materials

Coercivity and hardness of several materials

Principles of magnetoelastic sensors

Non-contact torque sensor

Principle of cross torductor torque

sensor and flux pattern of sensor

poles on the surface of a shaft

a) without and b)with torsional load

Equivalent magnetic circuit of

cross type torque sensor

Helices of principal tensile and compressive stress on the surface of

a shaft subjected to torsion [32] Correlated changes of permeability

are detected by four-branch yoke system with sensing coils 123

and 4 and a common excitation pole

Examples of torque sensors

Four-branch type torque sensor

heads Pole structures realized

by commercial multi-pole

ferrites 14 and 18 min in

diameter (diameter of sensor

h e a d 1 7 a n d 2 4 m m

respectively) respectively)

Principle of Ring Torductor torque transducer

(a b) Physical structure (c) evolution of the

shaft surface under the transducer poles A and BRing torductor for measuring

torque on ship propeller shafts

(shaft diameter ca 500 mm)

(Courtesy ASEA Brown

Boveri AG)

Principal designs of coaxial torque sensors

Schematic diagram of data processing

electronics of a torque sensor

Extensometer (a) Construction of strain sensing element using

amorphous ribbon wound core (b) configuration of lumped

windings

∆E effect of an amorphous FeNi-based

alloy (Fe40 Ni38 Mo4 B18) Hs saturation

field

Magnetically tunable delay line

Torque Sensors using Amorphous wire

Sixtus tonk효과(large Barkhausen효과)

Hysteresis loops of a Wiegand wire for different reset fields

Curie 온도 및Hopkinson효과

Relation between normalised

saturation polarisation and

normalised Curie temperature

Permeability of a Mn-Zn ferrite as

a function of temperature and field

strength

Conclusions

1) Magnetic sensor 는 자동차 공장자동화 항공우주 및 군사용으로많이 사용되고 있다

2) 새로운 소재개발은 자기센서의 성능개발에 직접적인 영향을 준다2) 새로운 소재개발은 자기센서의 성능개발에 직접적인 영향을 준다

3) 센서의 개발을 위해서는 다양한 전공지식이 요구된다

(물리학 재료공학 기계공학 전자공학)

4) 센서분야가 고부가가치를 창출하는 부품사업이다

5) 핵심부품을 생산하는 중소기업의 item으로도 적절하다

)( cos~ rt1r αα minussdotUU

Principle of construction of a control-type sensor

Output voltage versus

angular difference

Principle of construction of a differential sychro

Eddy Current Sensors

tBE dd curl minus=JH = curl

0 div =BH(H)B sdot= micro

E(E)J sdot= σ

A B curl= A B curl=

tdd- A E =

)dd( tAJ minus= σ

tdd curl curl AA σmicro minus=

AA) σωmicro iminus= curl )(curl(1

AA) σωmicro i=∆)((1

Eddy Current Tachometer

Construction of a speedometer (courtesy VDO Adolf Schinding AG) 1) spindle 2) bearing

3) holding spring 4) iron yoke 5) eddy current cup 6) shaft of the magnet 7) support of

the magnet 8) temperature compensation 9) permanent magnet 10) torsion spring

Proximity Sensors

Schematic diagram of a proximity sensor

Output current of a proximity switch versus distance

Inductive Flowmeters

)( Btimessdot= υqF

EqF sdot=BE times=υ

)(ds Btimes== υEU )(ds Btimes== υEU

)( Bd timessdot= υU

Bsdotsdotsdot= υdKU

Development of magnetic phase detection

sensor for steam generator tube

Dirac Son1 Kwan-Sang Ryu2 Duck-Gun Park3

1Hannam University Daejeon Rep of Korea2Korea Research Institute of Standards and Science Daejeon Rep of Korea3KoreaAtomic Energy Research Institute Daejeon Rep of Korea

Introduction

The layout of pressurized water reactor (PWR) components

Primary side Secondary side (non-radioactive side)(radioactive side)

The Structure of SG(Steam Generator)(degradation mechanism)

Secondary SidePrimary Side

SCC

A B

A-B

Steam outlet

Anti-vibration

SCC

Fretting

Wall thinning

IGA

U-bend

In commercial power plants SG- height up to 21 m - weight up to 800 tons - 2~4 sets of SG were installed - SG can contain from 3000 to

16000 tubes each about 20 mmin diameter

Primary coolant outlet Primary coolant inlet

Anti-vibrationbars

Tubesupportplate

Tubesheet

IGA

SCC

Pitting

SCC

Inside Tubesheet

Top of Tubesheet

by SSHwang of KAERI

Denting

Sludge pile

in diameter

The SGT is made of nickel basedInconel alloy which is composed of 75 Ni 165Cr and 815Fe

-Degradation mechanism corrosion pitting denting inter granular attack

-Inspection Eddy current Testing(ECT)

Permeability Variation Clusters (PVC)

(Ferro-magnetic phase)

-005

000

005

010

015

m (emug)

1-1

-002

000

002

004

006

008

m (emug)

1-2

-1000 -500 0 500 1000

-015

-010

-005

H ( Am )

-1000 -500 0 500 1000

-006

-004

-002

H ( Am )

The hystresis loop in the fragment of PVC parts of Kori-1 retired SG tube

-004

-002

000

002

004

006

M (emug)

Inconel 600 tested at RT

under tensile stress

1 2 3

4 5 6

7 8 9-004

-002

000

002

004

006

M(emug)

Inconel 600 Heat treated at

602 oC under tensile stress

1 2 3

How can we detect magnetic phase

(PVC)selectively from the flaws in SGT

-3000 -2000 -1000 0 1000 2000 3000

-006

H (Oe)

7 8 9

10 11 12

-3000 -2000 -1000 0 1000 2000 3000

-006

-004

H(Oe)

4 5 6

7 8 9

The hysteresis loop of the tensile tested specimen at room temperature (a) and tensile tested at high temperature (b)

The magnetic phase can be created under the high temperature andpressure conditions which is correspond to the stress corrosion crackingin the SG tube in the NPP(Bruemmer SM Charlot LA amp Henager CH (1988) Corrosion 782)

Principle of ECT

If we can separate magnetic phase selectively from the

flaws using magnetic sensor the reliability of EC in SGT

inspection will be greatly enhanced

Structure of the permeability

sensor

Dimension and photograph of U-shape

sensing yoke

Design of Magnetic Sensor for PVC

sensor sensing yoke

Photograph of the completed sensor front side (above) and rear side (bottom)

R11R12

R10

R8

R6

R9

R13

R7

R14

C18

1 n

C17

C20

C21

D2

DIODE

SIN COS

-

+

U-2A

4

13

2

-

+

U-2B

75

6

8

-

+

U-3A

13

2

8

+5VC19

104

+5V

Schematic diagram of the sensor system

Electronic Circuit of Magnetic Sensor

R20

R

R21

R

-

+

U5AD797

3

26

74

U6

D1

S12

GND3

+VCC4VCC5

IN6

-VCC7

S28

C41

R13

R26

R18

R25

R2210 Ω

R16

R14

R17

10 k

R15

R27

R32

R28

R33

R29

R34

5 k

R30

C29

C37

104

C32473

C39473C40

104

C33

104

C21

104C23

104

C25

104

C26

104

C30

104

C31

104

C35

104

C36

104

C27

104

C28

104

C34

104

C38

104

D3

DIODE

L1

1

2

L2

1

2

L3

1

2

4

-

+

U-4A

4

13

2

-

+

U-4B

75

6

8

-

+

U-5A

4

13

2

-

+

U-5B

75

6

8

-

+

U-6A

4

13

2

-

+

U-6B

75

6

8

C22

104

-5V

+5V

+5V

+5V

+5V

+5V

+5V

U7

D1

S12

GND3

+VCC4

VCC5

IN6

-VCC7

S28

+5V

-5V

-5V

-5V

-5V

-5V

-5V

-5V

-5V

R19

R24

R

R23

R

C24

OUT(X)

OUT(Y)

R1

20 kR210 k

R3

20 kR410 k

C1

104

C8

104

REF43

OUT(X)

OUT(Y)

REF43

U2

+Vcc1

CH02

CH13

CH24

CH35

COMM6

SHDN7

Vref8

+Vcc9

GND10

GND11

DOUT12BUSY13DIN14CS15

DIN16

-

+

U-1A

13

2

8

-

+

U-1B

4

75

6

C410 uF

C5104

DOUT

C210uF

C6104

C3104

DCLK

C7104

DIN

C10

01uF

CS

BUSY

C14 10uF

J1

CON6

123456

D1

DIODE

R5

47K

C9

10uF

C1310uF

Y1

OSC

OUT3

GND2

VCC4

U3

RSTVPP1

GND10

VCC20

XTAL15

XTAL24

P10AIN012P11AIN113P1214P1315P1416P1517P1618P1719

P30RXD2

P31TXD3

P32INT06

P33INT17

P34T08

P35T19

P3711

U4

C1+1

C1-3

C2+4

C2-5

VCC16

GND15

V+2

V-6

R1OUT12

R2OUT9

T1IN11

T2IN10

R1IN13

R2IN8

T1OUT14

T2OUT7

C12 10uF

C16

01uF

C15 10uF

C11

01uF

-5V

+5V

+5V

+5V

+5V

+5V

+5V

+5V

RST

OSC

OSC

RST

DCLKCSDINBUSYDOUT

U1

IN2

GND

4

OUT6

TEMP3

TRIM5

-5V

+5V

Electronic circuit diagram of the magnetic sensor

Photograph of the completed measuring system data acquisition

software in PC and probe scanning system

Experimental Setup for Magnetic Sensor

Reference material Scanning System Software LabVIEW

Reference Material (1) Normal defects and PVCs

Longitudinal and transverse defects

Def W L D Remarks

1 02 500 0213 (20 ) Inner defects

2 02 500 0427 (40 )

3 02 500 0213 (20 )Outer defectsPVC(1018)4 02 500 0427 (40 )

5 02 500 0639 (60 )

6 02 500 0852 (80 )

7 02 500 0639 (60 ) Inner defects

8 02 500 0852 (80 )

- 1 and 2 are inner defects

- 345 and 6 are outer defects with PVC

- 7 and 8 are inner defects

PVC

PVC

Defect Defect

For longitudinal defects and PVC For circumferential defects and PVC

ECT is very difficult to detect circumferential defects

We can distinguish PVCs and defects and longitudinal and circumferential defects

Flux-gate Magnetometer

One core sensor Two core sensor

3-축 flux-gate Magnetometer의 계략도

Sensorpia Co

pro

cess

or(

AV

R)

Sensor 1

RS422

Interface

Mic

ro-p

roce

ssor(

AV

R)

Sensor 2

Sensor 3

Interface

조립된 마그네토미터의 사진

Sensorpia Co

Analog PCB

Digital PCB

Sensorpia Co선형도(linearity)

10

20

30

40

50

60

y-axis

Magnetometer Output (microT)

-60 -50 -40 -30 -20 -10 0 10 20 30 40 50 60

-60

-50

-40

-30

-20

-10

0

10

Y-axis y=099946 x+0015STD 106E-4

Magnetometer Output (

Applied Magnetic Field (microT)

마그네토미터의 noise 특성 Sensorpia Co

1

10

100

y-axis

Magnetometer noise (nT)

0 1 2 3 4 5 6

1E-4

1E-3

001

01

Magnetometer noise (nT)

Frequency (Hz)

Magnetometer for KoDSAT

-150 -100 -50 0 50 100 150

-15

-10

-5

0

5

10

15

Magnetic Moment (Am

2)

Current (mA)

After Thermal Cycle Test

Measured

Resistance 193 ohm

Photograph of Magnetic torquer

Photograph of KoDSAT

Photograph of

3-axis Fluxgate

Magnetometer

Photograph of Magnetic torquer

Application of magnetometer

Moon magnetic fieldmeasurement

Telescope with direction indication

Joule Effect (Magnetostriction)

ϕ2cosel

l=

∆

0=∆

+∆

+∆

b

b

a

a

l

l

Actuator using Terfenol-D

00

05

10

B (T)

800

1000

1200

1400

1600

Magnetostriction (ppm)

-100 -50 0 50 100

-10

-05

00

B (T)

H (kAm)

2 MPa

4 MPa

6 MPa

8 MPa

10 MPa

12 MPa

-100 -50 0 50 100

-200

0

200

400

600

Magnetostriction (ppm)

H (kAm)

2 MPa

4 MPa

6 MPa

8 MPa

10 MPa

12 MPa

600

700

800

900

1000

-4 -3 -2 -1 0 1 2 3 4

0

10

20

30

40

50

60

Displacement (m

icro meter)

I (A)

FIELD

9 kAm

12 kAm

16 kAm

20 kAm

24 kAm

38 kAm

-50 -40 -30 -20 -10 0 10 20 30 40 50

-100

0

100

200

300

400

500

L (PPM)

H (kAm)

9 kAm

12 kAm

16 kAm

20 kAm

24 kAm

38 kAm

Magnetostrictive displacement sensor

Hysteresis loops under

tensile stress σ

(a) Crystalline 68 NiFe

λs = +25 10-6

(b) crystalline pure Ni λs

= -35 10-6

Villari Effect ( Inverse of Joule Effect)

= -35 10-6

(c) amorphous Co-based

alloy

λs = -35 10-6

ϕσλ 2sin2

3sdotsdot= smeE

γ

Permeability depending on the stress

σλmicromicro

1

3

2

Y

J

so

s

r =

γ

Calculated magnetization curves under stress

Variation of magnetization curve by an applied

tensile force (Co-based amorphous alloy)

Alloy Requirement

Materials for magnetoelastic sensors

Why amorphous magnetic materials are important

Stress-strain curves of several materials

Coercivity and hardness of several materials

Principles of magnetoelastic sensors

Non-contact torque sensor

Principle of cross torductor torque

sensor and flux pattern of sensor

poles on the surface of a shaft

a) without and b)with torsional load

Equivalent magnetic circuit of

cross type torque sensor

Helices of principal tensile and compressive stress on the surface of

a shaft subjected to torsion [32] Correlated changes of permeability

are detected by four-branch yoke system with sensing coils 123

and 4 and a common excitation pole

Examples of torque sensors

Four-branch type torque sensor

heads Pole structures realized

by commercial multi-pole

ferrites 14 and 18 min in

diameter (diameter of sensor

h e a d 1 7 a n d 2 4 m m

respectively) respectively)

Principle of Ring Torductor torque transducer

(a b) Physical structure (c) evolution of the

shaft surface under the transducer poles A and BRing torductor for measuring

torque on ship propeller shafts

(shaft diameter ca 500 mm)

(Courtesy ASEA Brown

Boveri AG)

Principal designs of coaxial torque sensors

Schematic diagram of data processing

electronics of a torque sensor

Extensometer (a) Construction of strain sensing element using

amorphous ribbon wound core (b) configuration of lumped

windings

∆E effect of an amorphous FeNi-based

alloy (Fe40 Ni38 Mo4 B18) Hs saturation

field

Magnetically tunable delay line

Torque Sensors using Amorphous wire

Sixtus tonk효과(large Barkhausen효과)

Hysteresis loops of a Wiegand wire for different reset fields

Curie 온도 및Hopkinson효과

Relation between normalised

saturation polarisation and

normalised Curie temperature

Permeability of a Mn-Zn ferrite as

a function of temperature and field

strength

Conclusions

1) Magnetic sensor 는 자동차 공장자동화 항공우주 및 군사용으로많이 사용되고 있다

2) 새로운 소재개발은 자기센서의 성능개발에 직접적인 영향을 준다2) 새로운 소재개발은 자기센서의 성능개발에 직접적인 영향을 준다

3) 센서의 개발을 위해서는 다양한 전공지식이 요구된다

(물리학 재료공학 기계공학 전자공학)

4) 센서분야가 고부가가치를 창출하는 부품사업이다

5) 핵심부품을 생산하는 중소기업의 item으로도 적절하다

Output voltage versus

angular difference

Principle of construction of a differential sychro

Eddy Current Sensors

tBE dd curl minus=JH = curl

0 div =BH(H)B sdot= micro

E(E)J sdot= σ

A B curl= A B curl=

tdd- A E =

)dd( tAJ minus= σ

tdd curl curl AA σmicro minus=

AA) σωmicro iminus= curl )(curl(1

AA) σωmicro i=∆)((1

Eddy Current Tachometer

Construction of a speedometer (courtesy VDO Adolf Schinding AG) 1) spindle 2) bearing

3) holding spring 4) iron yoke 5) eddy current cup 6) shaft of the magnet 7) support of

the magnet 8) temperature compensation 9) permanent magnet 10) torsion spring

Proximity Sensors

Schematic diagram of a proximity sensor

Output current of a proximity switch versus distance

Inductive Flowmeters

)( Btimessdot= υqF

EqF sdot=BE times=υ

)(ds Btimes== υEU )(ds Btimes== υEU

)( Bd timessdot= υU

Bsdotsdotsdot= υdKU

Development of magnetic phase detection

sensor for steam generator tube

Dirac Son1 Kwan-Sang Ryu2 Duck-Gun Park3

1Hannam University Daejeon Rep of Korea2Korea Research Institute of Standards and Science Daejeon Rep of Korea3KoreaAtomic Energy Research Institute Daejeon Rep of Korea

Introduction

The layout of pressurized water reactor (PWR) components

Primary side Secondary side (non-radioactive side)(radioactive side)

The Structure of SG(Steam Generator)(degradation mechanism)

Secondary SidePrimary Side

SCC

A B

A-B

Steam outlet

Anti-vibration

SCC

Fretting

Wall thinning

IGA

U-bend

In commercial power plants SG- height up to 21 m - weight up to 800 tons - 2~4 sets of SG were installed - SG can contain from 3000 to

16000 tubes each about 20 mmin diameter

Primary coolant outlet Primary coolant inlet

Anti-vibrationbars

Tubesupportplate

Tubesheet

IGA

SCC

Pitting

SCC

Inside Tubesheet

Top of Tubesheet

by SSHwang of KAERI

Denting

Sludge pile

in diameter

The SGT is made of nickel basedInconel alloy which is composed of 75 Ni 165Cr and 815Fe

-Degradation mechanism corrosion pitting denting inter granular attack

-Inspection Eddy current Testing(ECT)

Permeability Variation Clusters (PVC)

(Ferro-magnetic phase)

-005

000

005

010

015

m (emug)

1-1

-002

000

002

004

006

008

m (emug)

1-2

-1000 -500 0 500 1000

-015

-010

-005

H ( Am )

-1000 -500 0 500 1000

-006

-004

-002

H ( Am )

The hystresis loop in the fragment of PVC parts of Kori-1 retired SG tube

-004

-002

000

002

004

006

M (emug)

Inconel 600 tested at RT

under tensile stress

1 2 3

4 5 6

7 8 9-004

-002

000

002

004

006

M(emug)

Inconel 600 Heat treated at

602 oC under tensile stress

1 2 3

How can we detect magnetic phase

(PVC)selectively from the flaws in SGT

-3000 -2000 -1000 0 1000 2000 3000

-006

H (Oe)

7 8 9

10 11 12

-3000 -2000 -1000 0 1000 2000 3000

-006

-004

H(Oe)

4 5 6

7 8 9

The hysteresis loop of the tensile tested specimen at room temperature (a) and tensile tested at high temperature (b)

The magnetic phase can be created under the high temperature andpressure conditions which is correspond to the stress corrosion crackingin the SG tube in the NPP(Bruemmer SM Charlot LA amp Henager CH (1988) Corrosion 782)

Principle of ECT

If we can separate magnetic phase selectively from the

flaws using magnetic sensor the reliability of EC in SGT

inspection will be greatly enhanced

Structure of the permeability

sensor

Dimension and photograph of U-shape

sensing yoke

Design of Magnetic Sensor for PVC

sensor sensing yoke

Photograph of the completed sensor front side (above) and rear side (bottom)

R11R12

R10

R8

R6

R9

R13

R7

R14

C18

1 n

C17

C20

C21

D2

DIODE

SIN COS

-

+

U-2A

4

13

2

-

+

U-2B

75

6

8

-

+

U-3A

13

2

8

+5VC19

104

+5V

Schematic diagram of the sensor system

Electronic Circuit of Magnetic Sensor

R20

R

R21

R

-

+

U5AD797

3

26

74

U6

D1

S12

GND3

+VCC4VCC5

IN6

-VCC7

S28

C41

R13

R26

R18

R25

R2210 Ω

R16

R14

R17

10 k

R15

R27

R32

R28

R33

R29

R34

5 k

R30

C29

C37

104

C32473

C39473C40

104

C33

104

C21

104C23

104

C25

104

C26

104

C30

104

C31

104

C35

104

C36

104

C27

104

C28

104

C34

104

C38

104

D3

DIODE

L1

1

2

L2

1

2

L3

1

2

4

-

+

U-4A

4

13

2

-

+

U-4B

75

6

8

-

+

U-5A

4

13

2

-

+

U-5B

75

6

8

-

+

U-6A

4

13

2

-

+

U-6B

75

6

8

C22

104

-5V

+5V

+5V

+5V

+5V

+5V

+5V

U7

D1

S12

GND3

+VCC4

VCC5

IN6

-VCC7

S28

+5V

-5V

-5V

-5V

-5V

-5V

-5V

-5V

-5V

R19

R24

R

R23

R

C24

OUT(X)

OUT(Y)

R1

20 kR210 k

R3

20 kR410 k

C1

104

C8

104

REF43

OUT(X)

OUT(Y)

REF43

U2

+Vcc1

CH02

CH13

CH24

CH35

COMM6

SHDN7

Vref8

+Vcc9

GND10

GND11

DOUT12BUSY13DIN14CS15

DIN16

-

+

U-1A

13

2

8

-

+

U-1B

4

75

6

C410 uF

C5104

DOUT

C210uF

C6104

C3104

DCLK

C7104

DIN

C10

01uF

CS

BUSY

C14 10uF

J1

CON6

123456

D1

DIODE

R5

47K

C9

10uF

C1310uF

Y1

OSC

OUT3

GND2

VCC4

U3

RSTVPP1

GND10

VCC20

XTAL15

XTAL24

P10AIN012P11AIN113P1214P1315P1416P1517P1618P1719

P30RXD2

P31TXD3

P32INT06

P33INT17

P34T08

P35T19

P3711

U4

C1+1

C1-3

C2+4

C2-5

VCC16

GND15

V+2

V-6

R1OUT12

R2OUT9

T1IN11

T2IN10

R1IN13

R2IN8

T1OUT14

T2OUT7

C12 10uF

C16

01uF

C15 10uF

C11

01uF

-5V

+5V

+5V

+5V

+5V

+5V

+5V

+5V

RST

OSC

OSC

RST

DCLKCSDINBUSYDOUT

U1

IN2

GND

4

OUT6

TEMP3

TRIM5

-5V

+5V

Electronic circuit diagram of the magnetic sensor

Photograph of the completed measuring system data acquisition

software in PC and probe scanning system

Experimental Setup for Magnetic Sensor

Reference material Scanning System Software LabVIEW

Reference Material (1) Normal defects and PVCs

Longitudinal and transverse defects

Def W L D Remarks

1 02 500 0213 (20 ) Inner defects

2 02 500 0427 (40 )

3 02 500 0213 (20 )Outer defectsPVC(1018)4 02 500 0427 (40 )

5 02 500 0639 (60 )

6 02 500 0852 (80 )

7 02 500 0639 (60 ) Inner defects

8 02 500 0852 (80 )

- 1 and 2 are inner defects

- 345 and 6 are outer defects with PVC

- 7 and 8 are inner defects

PVC

PVC

Defect Defect

For longitudinal defects and PVC For circumferential defects and PVC

ECT is very difficult to detect circumferential defects

We can distinguish PVCs and defects and longitudinal and circumferential defects

Flux-gate Magnetometer

One core sensor Two core sensor

3-축 flux-gate Magnetometer의 계략도

Sensorpia Co

pro

cess

or(

AV

R)

Sensor 1

RS422

Interface

Mic

ro-p

roce

ssor(

AV

R)

Sensor 2

Sensor 3

Interface

조립된 마그네토미터의 사진

Sensorpia Co

Analog PCB

Digital PCB

Sensorpia Co선형도(linearity)

10

20

30

40

50

60

y-axis

Magnetometer Output (microT)

-60 -50 -40 -30 -20 -10 0 10 20 30 40 50 60

-60

-50

-40

-30

-20

-10

0

10

Y-axis y=099946 x+0015STD 106E-4

Magnetometer Output (

Applied Magnetic Field (microT)

마그네토미터의 noise 특성 Sensorpia Co

1

10

100

y-axis

Magnetometer noise (nT)

0 1 2 3 4 5 6

1E-4

1E-3

001

01

Magnetometer noise (nT)

Frequency (Hz)

Magnetometer for KoDSAT

-150 -100 -50 0 50 100 150

-15

-10

-5

0

5

10

15

Magnetic Moment (Am

2)

Current (mA)

After Thermal Cycle Test

Measured

Resistance 193 ohm

Photograph of Magnetic torquer

Photograph of KoDSAT

Photograph of

3-axis Fluxgate

Magnetometer

Photograph of Magnetic torquer

Application of magnetometer

Moon magnetic fieldmeasurement

Telescope with direction indication

Joule Effect (Magnetostriction)

ϕ2cosel

l=

∆

0=∆

+∆

+∆

b

b

a

a

l

l

Actuator using Terfenol-D

00

05

10

B (T)

800

1000

1200

1400

1600

Magnetostriction (ppm)

-100 -50 0 50 100

-10

-05

00

B (T)

H (kAm)

2 MPa

4 MPa

6 MPa

8 MPa

10 MPa

12 MPa

-100 -50 0 50 100

-200

0

200

400

600

Magnetostriction (ppm)

H (kAm)

2 MPa

4 MPa

6 MPa

8 MPa

10 MPa

12 MPa

600

700

800

900

1000

-4 -3 -2 -1 0 1 2 3 4

0

10

20

30

40

50

60

Displacement (m

icro meter)

I (A)

FIELD

9 kAm

12 kAm

16 kAm

20 kAm

24 kAm

38 kAm

-50 -40 -30 -20 -10 0 10 20 30 40 50

-100

0

100

200

300

400

500

L (PPM)

H (kAm)

9 kAm

12 kAm

16 kAm

20 kAm

24 kAm

38 kAm

Magnetostrictive displacement sensor

Hysteresis loops under

tensile stress σ

(a) Crystalline 68 NiFe

λs = +25 10-6

(b) crystalline pure Ni λs

= -35 10-6

Villari Effect ( Inverse of Joule Effect)

= -35 10-6

(c) amorphous Co-based

alloy

λs = -35 10-6

ϕσλ 2sin2

3sdotsdot= smeE

γ

Permeability depending on the stress

σλmicromicro

1

3

2

Y

J

so

s

r =

γ

Calculated magnetization curves under stress

Variation of magnetization curve by an applied

tensile force (Co-based amorphous alloy)

Alloy Requirement

Materials for magnetoelastic sensors

Why amorphous magnetic materials are important

Stress-strain curves of several materials

Coercivity and hardness of several materials

Principles of magnetoelastic sensors

Non-contact torque sensor

Principle of cross torductor torque

sensor and flux pattern of sensor

poles on the surface of a shaft

a) without and b)with torsional load

Equivalent magnetic circuit of

cross type torque sensor

Helices of principal tensile and compressive stress on the surface of

a shaft subjected to torsion [32] Correlated changes of permeability

are detected by four-branch yoke system with sensing coils 123

and 4 and a common excitation pole

Examples of torque sensors

Four-branch type torque sensor

heads Pole structures realized

by commercial multi-pole

ferrites 14 and 18 min in

diameter (diameter of sensor

h e a d 1 7 a n d 2 4 m m

respectively) respectively)

Principle of Ring Torductor torque transducer

(a b) Physical structure (c) evolution of the

shaft surface under the transducer poles A and BRing torductor for measuring

torque on ship propeller shafts

(shaft diameter ca 500 mm)

(Courtesy ASEA Brown

Boveri AG)

Principal designs of coaxial torque sensors

Schematic diagram of data processing

electronics of a torque sensor

Extensometer (a) Construction of strain sensing element using

amorphous ribbon wound core (b) configuration of lumped

windings

∆E effect of an amorphous FeNi-based

alloy (Fe40 Ni38 Mo4 B18) Hs saturation

field

Magnetically tunable delay line

Torque Sensors using Amorphous wire

Sixtus tonk효과(large Barkhausen효과)

Hysteresis loops of a Wiegand wire for different reset fields

Curie 온도 및Hopkinson효과

Relation between normalised

saturation polarisation and

normalised Curie temperature

Permeability of a Mn-Zn ferrite as

a function of temperature and field

strength

Conclusions

1) Magnetic sensor 는 자동차 공장자동화 항공우주 및 군사용으로많이 사용되고 있다

2) 새로운 소재개발은 자기센서의 성능개발에 직접적인 영향을 준다2) 새로운 소재개발은 자기센서의 성능개발에 직접적인 영향을 준다

3) 센서의 개발을 위해서는 다양한 전공지식이 요구된다

(물리학 재료공학 기계공학 전자공학)

4) 센서분야가 고부가가치를 창출하는 부품사업이다

5) 핵심부품을 생산하는 중소기업의 item으로도 적절하다

Eddy Current Sensors

tBE dd curl minus=JH = curl

0 div =BH(H)B sdot= micro

E(E)J sdot= σ

A B curl= A B curl=

tdd- A E =

)dd( tAJ minus= σ

tdd curl curl AA σmicro minus=

AA) σωmicro iminus= curl )(curl(1

AA) σωmicro i=∆)((1

Eddy Current Tachometer

Construction of a speedometer (courtesy VDO Adolf Schinding AG) 1) spindle 2) bearing

3) holding spring 4) iron yoke 5) eddy current cup 6) shaft of the magnet 7) support of

the magnet 8) temperature compensation 9) permanent magnet 10) torsion spring

Proximity Sensors

Schematic diagram of a proximity sensor

Output current of a proximity switch versus distance

Inductive Flowmeters

)( Btimessdot= υqF

EqF sdot=BE times=υ

)(ds Btimes== υEU )(ds Btimes== υEU

)( Bd timessdot= υU

Bsdotsdotsdot= υdKU

Development of magnetic phase detection

sensor for steam generator tube

Dirac Son1 Kwan-Sang Ryu2 Duck-Gun Park3

1Hannam University Daejeon Rep of Korea2Korea Research Institute of Standards and Science Daejeon Rep of Korea3KoreaAtomic Energy Research Institute Daejeon Rep of Korea

Introduction

The layout of pressurized water reactor (PWR) components

Primary side Secondary side (non-radioactive side)(radioactive side)

The Structure of SG(Steam Generator)(degradation mechanism)

Secondary SidePrimary Side

SCC

A B

A-B

Steam outlet

Anti-vibration

SCC

Fretting

Wall thinning

IGA

U-bend

In commercial power plants SG- height up to 21 m - weight up to 800 tons - 2~4 sets of SG were installed - SG can contain from 3000 to

16000 tubes each about 20 mmin diameter

Primary coolant outlet Primary coolant inlet

Anti-vibrationbars

Tubesupportplate

Tubesheet

IGA

SCC

Pitting

SCC

Inside Tubesheet

Top of Tubesheet

by SSHwang of KAERI

Denting

Sludge pile

in diameter

The SGT is made of nickel basedInconel alloy which is composed of 75 Ni 165Cr and 815Fe

-Degradation mechanism corrosion pitting denting inter granular attack

-Inspection Eddy current Testing(ECT)

Permeability Variation Clusters (PVC)

(Ferro-magnetic phase)

-005

000

005

010

015

m (emug)

1-1

-002

000

002

004

006

008

m (emug)

1-2

-1000 -500 0 500 1000

-015

-010

-005

H ( Am )

-1000 -500 0 500 1000

-006

-004

-002

H ( Am )

The hystresis loop in the fragment of PVC parts of Kori-1 retired SG tube

-004

-002

000

002

004

006

M (emug)

Inconel 600 tested at RT

under tensile stress

1 2 3

4 5 6

7 8 9-004

-002

000

002

004

006

M(emug)

Inconel 600 Heat treated at

602 oC under tensile stress

1 2 3

How can we detect magnetic phase

(PVC)selectively from the flaws in SGT

-3000 -2000 -1000 0 1000 2000 3000

-006

H (Oe)

7 8 9

10 11 12

-3000 -2000 -1000 0 1000 2000 3000

-006

-004

H(Oe)

4 5 6

7 8 9

The hysteresis loop of the tensile tested specimen at room temperature (a) and tensile tested at high temperature (b)

The magnetic phase can be created under the high temperature andpressure conditions which is correspond to the stress corrosion crackingin the SG tube in the NPP(Bruemmer SM Charlot LA amp Henager CH (1988) Corrosion 782)

Principle of ECT

If we can separate magnetic phase selectively from the

flaws using magnetic sensor the reliability of EC in SGT

inspection will be greatly enhanced

Structure of the permeability

sensor

Dimension and photograph of U-shape

sensing yoke

Design of Magnetic Sensor for PVC

sensor sensing yoke

Photograph of the completed sensor front side (above) and rear side (bottom)

R11R12

R10

R8

R6

R9

R13

R7

R14

C18

1 n

C17

C20

C21

D2

DIODE

SIN COS

-

+

U-2A

4

13

2

-

+

U-2B

75

6

8

-

+

U-3A

13

2

8

+5VC19

104

+5V

Schematic diagram of the sensor system

Electronic Circuit of Magnetic Sensor

R20

R

R21

R

-

+

U5AD797

3

26

74

U6

D1

S12

GND3

+VCC4VCC5

IN6

-VCC7

S28

C41

R13

R26

R18

R25

R2210 Ω

R16

R14

R17

10 k

R15

R27

R32

R28

R33

R29

R34

5 k

R30

C29

C37

104

C32473

C39473C40

104

C33

104

C21

104C23

104

C25

104

C26

104

C30

104

C31

104

C35

104

C36

104

C27

104

C28

104

C34

104

C38

104

D3

DIODE

L1

1

2

L2

1

2

L3

1

2

4

-

+

U-4A

4

13

2

-

+

U-4B

75

6

8

-

+

U-5A

4

13

2

-

+

U-5B

75

6

8

-

+

U-6A

4

13

2

-

+

U-6B

75

6

8

C22

104

-5V

+5V

+5V

+5V

+5V

+5V

+5V

U7

D1

S12

GND3

+VCC4

VCC5

IN6

-VCC7

S28

+5V

-5V

-5V

-5V

-5V

-5V

-5V

-5V

-5V

R19

R24

R

R23

R

C24

OUT(X)

OUT(Y)

R1

20 kR210 k

R3

20 kR410 k

C1

104

C8

104

REF43

OUT(X)

OUT(Y)

REF43

U2

+Vcc1

CH02

CH13

CH24

CH35

COMM6

SHDN7

Vref8

+Vcc9

GND10

GND11

DOUT12BUSY13DIN14CS15

DIN16

-

+

U-1A

13

2

8

-

+

U-1B

4

75

6

C410 uF

C5104

DOUT

C210uF

C6104

C3104

DCLK

C7104

DIN

C10

01uF

CS

BUSY

C14 10uF

J1

CON6

123456

D1

DIODE

R5

47K

C9

10uF

C1310uF

Y1

OSC

OUT3

GND2

VCC4

U3

RSTVPP1

GND10

VCC20

XTAL15

XTAL24

P10AIN012P11AIN113P1214P1315P1416P1517P1618P1719

P30RXD2

P31TXD3

P32INT06

P33INT17

P34T08

P35T19

P3711

U4

C1+1

C1-3

C2+4

C2-5

VCC16

GND15

V+2

V-6

R1OUT12

R2OUT9

T1IN11

T2IN10

R1IN13

R2IN8

T1OUT14

T2OUT7

C12 10uF

C16

01uF

C15 10uF

C11

01uF

-5V

+5V

+5V

+5V

+5V

+5V

+5V

+5V

RST

OSC

OSC

RST

DCLKCSDINBUSYDOUT

U1

IN2

GND

4

OUT6

TEMP3

TRIM5

-5V

+5V

Electronic circuit diagram of the magnetic sensor

Photograph of the completed measuring system data acquisition

software in PC and probe scanning system

Experimental Setup for Magnetic Sensor

Reference material Scanning System Software LabVIEW

Reference Material (1) Normal defects and PVCs

Longitudinal and transverse defects

Def W L D Remarks

1 02 500 0213 (20 ) Inner defects

2 02 500 0427 (40 )

3 02 500 0213 (20 )Outer defectsPVC(1018)4 02 500 0427 (40 )

5 02 500 0639 (60 )

6 02 500 0852 (80 )

7 02 500 0639 (60 ) Inner defects

8 02 500 0852 (80 )

- 1 and 2 are inner defects

- 345 and 6 are outer defects with PVC

- 7 and 8 are inner defects

PVC

PVC

Defect Defect

For longitudinal defects and PVC For circumferential defects and PVC

ECT is very difficult to detect circumferential defects

We can distinguish PVCs and defects and longitudinal and circumferential defects

Flux-gate Magnetometer

One core sensor Two core sensor

3-축 flux-gate Magnetometer의 계략도

Sensorpia Co

pro

cess

or(

AV

R)

Sensor 1

RS422

Interface

Mic

ro-p

roce

ssor(

AV

R)

Sensor 2

Sensor 3

Interface

조립된 마그네토미터의 사진

Sensorpia Co

Analog PCB

Digital PCB

Sensorpia Co선형도(linearity)

10

20

30

40

50

60

y-axis

Magnetometer Output (microT)

-60 -50 -40 -30 -20 -10 0 10 20 30 40 50 60

-60

-50

-40

-30

-20

-10

0

10

Y-axis y=099946 x+0015STD 106E-4

Magnetometer Output (

Applied Magnetic Field (microT)

마그네토미터의 noise 특성 Sensorpia Co

1

10

100

y-axis

Magnetometer noise (nT)

0 1 2 3 4 5 6

1E-4

1E-3

001

01

Magnetometer noise (nT)

Frequency (Hz)

Magnetometer for KoDSAT

-150 -100 -50 0 50 100 150

-15

-10

-5

0

5

10

15

Magnetic Moment (Am

2)

Current (mA)

After Thermal Cycle Test

Measured

Resistance 193 ohm

Photograph of Magnetic torquer

Photograph of KoDSAT

Photograph of

3-axis Fluxgate

Magnetometer

Photograph of Magnetic torquer

Application of magnetometer

Moon magnetic fieldmeasurement

Telescope with direction indication

Joule Effect (Magnetostriction)

ϕ2cosel

l=

∆

0=∆

+∆

+∆

b

b

a

a

l

l

Actuator using Terfenol-D

00

05

10

B (T)

800

1000

1200

1400

1600

Magnetostriction (ppm)

-100 -50 0 50 100

-10

-05

00

B (T)

H (kAm)

2 MPa

4 MPa

6 MPa

8 MPa

10 MPa

12 MPa

-100 -50 0 50 100

-200

0

200

400

600

Magnetostriction (ppm)

H (kAm)

2 MPa

4 MPa

6 MPa

8 MPa

10 MPa

12 MPa

600

700

800

900

1000

-4 -3 -2 -1 0 1 2 3 4

0

10

20

30

40

50

60

Displacement (m

icro meter)

I (A)

FIELD

9 kAm

12 kAm

16 kAm

20 kAm

24 kAm

38 kAm

-50 -40 -30 -20 -10 0 10 20 30 40 50

-100

0

100

200

300

400

500

L (PPM)

H (kAm)

9 kAm

12 kAm

16 kAm

20 kAm

24 kAm

38 kAm

Magnetostrictive displacement sensor

Hysteresis loops under

tensile stress σ

(a) Crystalline 68 NiFe

λs = +25 10-6

(b) crystalline pure Ni λs

= -35 10-6

Villari Effect ( Inverse of Joule Effect)

= -35 10-6

(c) amorphous Co-based

alloy

λs = -35 10-6

ϕσλ 2sin2

3sdotsdot= smeE

γ

Permeability depending on the stress

σλmicromicro

1

3

2

Y

J

so

s

r =

γ

Calculated magnetization curves under stress

Variation of magnetization curve by an applied

tensile force (Co-based amorphous alloy)

Alloy Requirement

Materials for magnetoelastic sensors

Why amorphous magnetic materials are important

Stress-strain curves of several materials

Coercivity and hardness of several materials

Principles of magnetoelastic sensors

Non-contact torque sensor

Principle of cross torductor torque

sensor and flux pattern of sensor

poles on the surface of a shaft

a) without and b)with torsional load

Equivalent magnetic circuit of

cross type torque sensor

Helices of principal tensile and compressive stress on the surface of

a shaft subjected to torsion [32] Correlated changes of permeability

are detected by four-branch yoke system with sensing coils 123

and 4 and a common excitation pole

Examples of torque sensors

Four-branch type torque sensor

heads Pole structures realized

by commercial multi-pole

ferrites 14 and 18 min in

diameter (diameter of sensor

h e a d 1 7 a n d 2 4 m m

respectively) respectively)

Principle of Ring Torductor torque transducer

(a b) Physical structure (c) evolution of the

shaft surface under the transducer poles A and BRing torductor for measuring

torque on ship propeller shafts

(shaft diameter ca 500 mm)

(Courtesy ASEA Brown

Boveri AG)

Principal designs of coaxial torque sensors

Schematic diagram of data processing

electronics of a torque sensor

Extensometer (a) Construction of strain sensing element using

amorphous ribbon wound core (b) configuration of lumped

windings

∆E effect of an amorphous FeNi-based

alloy (Fe40 Ni38 Mo4 B18) Hs saturation

field

Magnetically tunable delay line

Torque Sensors using Amorphous wire

Sixtus tonk효과(large Barkhausen효과)

Hysteresis loops of a Wiegand wire for different reset fields

Curie 온도 및Hopkinson효과

Relation between normalised

saturation polarisation and

normalised Curie temperature

Permeability of a Mn-Zn ferrite as

a function of temperature and field

strength

Conclusions

1) Magnetic sensor 는 자동차 공장자동화 항공우주 및 군사용으로많이 사용되고 있다

2) 새로운 소재개발은 자기센서의 성능개발에 직접적인 영향을 준다2) 새로운 소재개발은 자기센서의 성능개발에 직접적인 영향을 준다

3) 센서의 개발을 위해서는 다양한 전공지식이 요구된다

(물리학 재료공학 기계공학 전자공학)

4) 센서분야가 고부가가치를 창출하는 부품사업이다

5) 핵심부품을 생산하는 중소기업의 item으로도 적절하다

Eddy Current Tachometer

Construction of a speedometer (courtesy VDO Adolf Schinding AG) 1) spindle 2) bearing

3) holding spring 4) iron yoke 5) eddy current cup 6) shaft of the magnet 7) support of

the magnet 8) temperature compensation 9) permanent magnet 10) torsion spring

Proximity Sensors

Schematic diagram of a proximity sensor

Output current of a proximity switch versus distance

Inductive Flowmeters

)( Btimessdot= υqF

EqF sdot=BE times=υ

)(ds Btimes== υEU )(ds Btimes== υEU

)( Bd timessdot= υU

Bsdotsdotsdot= υdKU

Development of magnetic phase detection

sensor for steam generator tube

Dirac Son1 Kwan-Sang Ryu2 Duck-Gun Park3

1Hannam University Daejeon Rep of Korea2Korea Research Institute of Standards and Science Daejeon Rep of Korea3KoreaAtomic Energy Research Institute Daejeon Rep of Korea

Introduction

The layout of pressurized water reactor (PWR) components

Primary side Secondary side (non-radioactive side)(radioactive side)

The Structure of SG(Steam Generator)(degradation mechanism)

Secondary SidePrimary Side

SCC

A B

A-B

Steam outlet

Anti-vibration

SCC

Fretting

Wall thinning

IGA

U-bend

In commercial power plants SG- height up to 21 m - weight up to 800 tons - 2~4 sets of SG were installed - SG can contain from 3000 to

16000 tubes each about 20 mmin diameter

Primary coolant outlet Primary coolant inlet

Anti-vibrationbars

Tubesupportplate

Tubesheet

IGA

SCC

Pitting

SCC

Inside Tubesheet

Top of Tubesheet

by SSHwang of KAERI

Denting

Sludge pile

in diameter

The SGT is made of nickel basedInconel alloy which is composed of 75 Ni 165Cr and 815Fe

-Degradation mechanism corrosion pitting denting inter granular attack

-Inspection Eddy current Testing(ECT)

Permeability Variation Clusters (PVC)

(Ferro-magnetic phase)

-005

000

005

010

015

m (emug)

1-1

-002

000

002

004

006

008

m (emug)

1-2

-1000 -500 0 500 1000

-015

-010

-005

H ( Am )

-1000 -500 0 500 1000

-006

-004

-002

H ( Am )

The hystresis loop in the fragment of PVC parts of Kori-1 retired SG tube

-004

-002

000

002

004

006

M (emug)

Inconel 600 tested at RT

under tensile stress

1 2 3

4 5 6

7 8 9-004

-002

000

002

004

006

M(emug)

Inconel 600 Heat treated at

602 oC under tensile stress

1 2 3

How can we detect magnetic phase

(PVC)selectively from the flaws in SGT

-3000 -2000 -1000 0 1000 2000 3000

-006

H (Oe)

7 8 9

10 11 12

-3000 -2000 -1000 0 1000 2000 3000

-006

-004

H(Oe)

4 5 6

7 8 9

The hysteresis loop of the tensile tested specimen at room temperature (a) and tensile tested at high temperature (b)

The magnetic phase can be created under the high temperature andpressure conditions which is correspond to the stress corrosion crackingin the SG tube in the NPP(Bruemmer SM Charlot LA amp Henager CH (1988) Corrosion 782)

Principle of ECT

If we can separate magnetic phase selectively from the

flaws using magnetic sensor the reliability of EC in SGT

inspection will be greatly enhanced

Structure of the permeability

sensor

Dimension and photograph of U-shape

sensing yoke

Design of Magnetic Sensor for PVC

sensor sensing yoke

Photograph of the completed sensor front side (above) and rear side (bottom)

R11R12

R10

R8

R6

R9

R13

R7

R14

C18

1 n

C17

C20

C21

D2

DIODE

SIN COS

-

+

U-2A

4

13

2

-

+

U-2B

75

6

8

-

+

U-3A

13

2

8

+5VC19

104

+5V

Schematic diagram of the sensor system

Electronic Circuit of Magnetic Sensor

R20

R

R21

R

-

+

U5AD797

3

26

74

U6

D1

S12

GND3

+VCC4VCC5

IN6

-VCC7

S28

C41

R13

R26

R18

R25

R2210 Ω

R16

R14

R17

10 k

R15

R27

R32

R28

R33

R29

R34

5 k

R30

C29

C37

104

C32473

C39473C40

104

C33

104

C21

104C23

104

C25

104

C26

104

C30

104

C31

104

C35

104

C36

104

C27

104

C28

104

C34

104

C38

104

D3

DIODE

L1

1

2

L2

1

2

L3

1

2

4

-

+

U-4A

4

13

2

-

+

U-4B

75

6

8

-

+

U-5A

4

13

2

-

+

U-5B

75

6

8

-

+

U-6A

4

13

2

-

+

U-6B

75

6

8

C22

104

-5V

+5V

+5V

+5V

+5V

+5V

+5V

U7

D1

S12

GND3

+VCC4

VCC5

IN6

-VCC7

S28

+5V

-5V

-5V

-5V

-5V

-5V

-5V

-5V

-5V

R19

R24

R

R23

R

C24

OUT(X)

OUT(Y)

R1

20 kR210 k

R3

20 kR410 k

C1

104

C8

104

REF43

OUT(X)

OUT(Y)

REF43

U2

+Vcc1

CH02

CH13

CH24

CH35

COMM6

SHDN7

Vref8

+Vcc9

GND10

GND11

DOUT12BUSY13DIN14CS15

DIN16

-

+

U-1A

13

2

8

-

+

U-1B

4

75

6

C410 uF

C5104

DOUT

C210uF

C6104

C3104

DCLK

C7104

DIN

C10

01uF

CS

BUSY

C14 10uF

J1

CON6

123456

D1

DIODE

R5

47K

C9

10uF

C1310uF

Y1

OSC

OUT3

GND2

VCC4

U3

RSTVPP1

GND10

VCC20

XTAL15

XTAL24

P10AIN012P11AIN113P1214P1315P1416P1517P1618P1719

P30RXD2

P31TXD3

P32INT06

P33INT17

P34T08

P35T19

P3711

U4

C1+1

C1-3

C2+4

C2-5

VCC16

GND15

V+2

V-6

R1OUT12

R2OUT9

T1IN11

T2IN10

R1IN13

R2IN8

T1OUT14

T2OUT7

C12 10uF

C16

01uF

C15 10uF

C11

01uF

-5V

+5V

+5V

+5V

+5V

+5V

+5V

+5V

RST

OSC

OSC

RST

DCLKCSDINBUSYDOUT

U1

IN2

GND

4

OUT6

TEMP3

TRIM5

-5V

+5V

Electronic circuit diagram of the magnetic sensor

Photograph of the completed measuring system data acquisition

software in PC and probe scanning system

Experimental Setup for Magnetic Sensor

Reference material Scanning System Software LabVIEW

Reference Material (1) Normal defects and PVCs

Longitudinal and transverse defects

Def W L D Remarks

1 02 500 0213 (20 ) Inner defects

2 02 500 0427 (40 )

3 02 500 0213 (20 )Outer defectsPVC(1018)4 02 500 0427 (40 )

5 02 500 0639 (60 )

6 02 500 0852 (80 )

7 02 500 0639 (60 ) Inner defects

8 02 500 0852 (80 )

- 1 and 2 are inner defects

- 345 and 6 are outer defects with PVC

- 7 and 8 are inner defects

PVC

PVC

Defect Defect

For longitudinal defects and PVC For circumferential defects and PVC

ECT is very difficult to detect circumferential defects

We can distinguish PVCs and defects and longitudinal and circumferential defects

Flux-gate Magnetometer

One core sensor Two core sensor

3-축 flux-gate Magnetometer의 계략도

Sensorpia Co

pro

cess

or(

AV

R)

Sensor 1

RS422

Interface

Mic

ro-p

roce

ssor(

AV

R)

Sensor 2

Sensor 3

Interface

조립된 마그네토미터의 사진

Sensorpia Co

Analog PCB

Digital PCB

Sensorpia Co선형도(linearity)

10

20

30

40

50

60

y-axis

Magnetometer Output (microT)

-60 -50 -40 -30 -20 -10 0 10 20 30 40 50 60

-60

-50

-40

-30

-20

-10

0

10

Y-axis y=099946 x+0015STD 106E-4

Magnetometer Output (

Applied Magnetic Field (microT)

마그네토미터의 noise 특성 Sensorpia Co

1

10

100

y-axis

Magnetometer noise (nT)

0 1 2 3 4 5 6

1E-4

1E-3

001

01

Magnetometer noise (nT)

Frequency (Hz)

Magnetometer for KoDSAT

-150 -100 -50 0 50 100 150

-15

-10

-5

0

5

10

15

Magnetic Moment (Am

2)

Current (mA)

After Thermal Cycle Test

Measured

Resistance 193 ohm

Photograph of Magnetic torquer

Photograph of KoDSAT

Photograph of

3-axis Fluxgate

Magnetometer

Photograph of Magnetic torquer

Application of magnetometer

Moon magnetic fieldmeasurement

Telescope with direction indication

Joule Effect (Magnetostriction)

ϕ2cosel

l=

∆

0=∆

+∆

+∆

b

b

a

a

l

l

Actuator using Terfenol-D

00

05

10

B (T)

800

1000

1200

1400

1600

Magnetostriction (ppm)

-100 -50 0 50 100

-10

-05

00

B (T)

H (kAm)

2 MPa

4 MPa

6 MPa

8 MPa

10 MPa

12 MPa

-100 -50 0 50 100

-200

0

200

400

600

Magnetostriction (ppm)

H (kAm)

2 MPa

4 MPa

6 MPa

8 MPa

10 MPa

12 MPa

600

700

800

900

1000

-4 -3 -2 -1 0 1 2 3 4

0

10

20

30

40

50

60

Displacement (m

icro meter)

I (A)

FIELD

9 kAm

12 kAm

16 kAm

20 kAm

24 kAm

38 kAm

-50 -40 -30 -20 -10 0 10 20 30 40 50

-100

0

100

200

300

400

500

L (PPM)

H (kAm)

9 kAm

12 kAm

16 kAm

20 kAm

24 kAm

38 kAm

Magnetostrictive displacement sensor

Hysteresis loops under

tensile stress σ

(a) Crystalline 68 NiFe

λs = +25 10-6

(b) crystalline pure Ni λs

= -35 10-6

Villari Effect ( Inverse of Joule Effect)

= -35 10-6

(c) amorphous Co-based

alloy

λs = -35 10-6

ϕσλ 2sin2

3sdotsdot= smeE

γ

Permeability depending on the stress

σλmicromicro

1

3

2

Y

J

so

s

r =

γ

Calculated magnetization curves under stress

Variation of magnetization curve by an applied

tensile force (Co-based amorphous alloy)

Alloy Requirement

Materials for magnetoelastic sensors

Why amorphous magnetic materials are important

Stress-strain curves of several materials

Coercivity and hardness of several materials

Principles of magnetoelastic sensors

Non-contact torque sensor

Principle of cross torductor torque

sensor and flux pattern of sensor

poles on the surface of a shaft

a) without and b)with torsional load

Equivalent magnetic circuit of

cross type torque sensor

Helices of principal tensile and compressive stress on the surface of

a shaft subjected to torsion [32] Correlated changes of permeability

are detected by four-branch yoke system with sensing coils 123

and 4 and a common excitation pole

Examples of torque sensors

Four-branch type torque sensor

heads Pole structures realized

by commercial multi-pole

ferrites 14 and 18 min in

diameter (diameter of sensor

h e a d 1 7 a n d 2 4 m m

respectively) respectively)

Principle of Ring Torductor torque transducer

(a b) Physical structure (c) evolution of the

shaft surface under the transducer poles A and BRing torductor for measuring

torque on ship propeller shafts

(shaft diameter ca 500 mm)

(Courtesy ASEA Brown

Boveri AG)

Principal designs of coaxial torque sensors

Schematic diagram of data processing

electronics of a torque sensor

Extensometer (a) Construction of strain sensing element using

amorphous ribbon wound core (b) configuration of lumped

windings

∆E effect of an amorphous FeNi-based

alloy (Fe40 Ni38 Mo4 B18) Hs saturation

field

Magnetically tunable delay line

Torque Sensors using Amorphous wire

Sixtus tonk효과(large Barkhausen효과)

Hysteresis loops of a Wiegand wire for different reset fields

Curie 온도 및Hopkinson효과

Relation between normalised

saturation polarisation and

normalised Curie temperature

Permeability of a Mn-Zn ferrite as

a function of temperature and field

strength

Conclusions

1) Magnetic sensor 는 자동차 공장자동화 항공우주 및 군사용으로많이 사용되고 있다

2) 새로운 소재개발은 자기센서의 성능개발에 직접적인 영향을 준다2) 새로운 소재개발은 자기센서의 성능개발에 직접적인 영향을 준다

3) 센서의 개발을 위해서는 다양한 전공지식이 요구된다

(물리학 재료공학 기계공학 전자공학)

4) 센서분야가 고부가가치를 창출하는 부품사업이다

5) 핵심부품을 생산하는 중소기업의 item으로도 적절하다

Proximity Sensors

Schematic diagram of a proximity sensor

Output current of a proximity switch versus distance

Inductive Flowmeters

)( Btimessdot= υqF

EqF sdot=BE times=υ

)(ds Btimes== υEU )(ds Btimes== υEU

)( Bd timessdot= υU

Bsdotsdotsdot= υdKU

Development of magnetic phase detection

sensor for steam generator tube

Dirac Son1 Kwan-Sang Ryu2 Duck-Gun Park3

1Hannam University Daejeon Rep of Korea2Korea Research Institute of Standards and Science Daejeon Rep of Korea3KoreaAtomic Energy Research Institute Daejeon Rep of Korea

Introduction

The layout of pressurized water reactor (PWR) components

Primary side Secondary side (non-radioactive side)(radioactive side)

The Structure of SG(Steam Generator)(degradation mechanism)

Secondary SidePrimary Side

SCC

A B

A-B

Steam outlet

Anti-vibration

SCC

Fretting

Wall thinning

IGA

U-bend

In commercial power plants SG- height up to 21 m - weight up to 800 tons - 2~4 sets of SG were installed - SG can contain from 3000 to

16000 tubes each about 20 mmin diameter

Primary coolant outlet Primary coolant inlet

Anti-vibrationbars

Tubesupportplate

Tubesheet

IGA

SCC

Pitting

SCC

Inside Tubesheet

Top of Tubesheet

by SSHwang of KAERI

Denting

Sludge pile

in diameter

The SGT is made of nickel basedInconel alloy which is composed of 75 Ni 165Cr and 815Fe

-Degradation mechanism corrosion pitting denting inter granular attack

-Inspection Eddy current Testing(ECT)

Permeability Variation Clusters (PVC)

(Ferro-magnetic phase)

-005

000

005

010

015

m (emug)

1-1

-002

000

002

004

006

008

m (emug)

1-2

-1000 -500 0 500 1000

-015

-010

-005

H ( Am )

-1000 -500 0 500 1000

-006

-004

-002

H ( Am )

The hystresis loop in the fragment of PVC parts of Kori-1 retired SG tube

-004

-002

000

002

004

006

M (emug)

Inconel 600 tested at RT

under tensile stress

1 2 3

4 5 6

7 8 9-004

-002

000

002

004

006

M(emug)

Inconel 600 Heat treated at

602 oC under tensile stress

1 2 3

How can we detect magnetic phase

(PVC)selectively from the flaws in SGT

-3000 -2000 -1000 0 1000 2000 3000

-006

H (Oe)

7 8 9

10 11 12

-3000 -2000 -1000 0 1000 2000 3000

-006

-004

H(Oe)

4 5 6

7 8 9

The hysteresis loop of the tensile tested specimen at room temperature (a) and tensile tested at high temperature (b)

The magnetic phase can be created under the high temperature andpressure conditions which is correspond to the stress corrosion crackingin the SG tube in the NPP(Bruemmer SM Charlot LA amp Henager CH (1988) Corrosion 782)

Principle of ECT

If we can separate magnetic phase selectively from the

flaws using magnetic sensor the reliability of EC in SGT

inspection will be greatly enhanced

Structure of the permeability

sensor

Dimension and photograph of U-shape

sensing yoke

Design of Magnetic Sensor for PVC

sensor sensing yoke

Photograph of the completed sensor front side (above) and rear side (bottom)

R11R12

R10

R8

R6

R9

R13

R7

R14

C18

1 n

C17

C20

C21

D2

DIODE

SIN COS

-

+

U-2A

4

13

2

-

+

U-2B

75

6

8

-

+

U-3A

13

2

8

+5VC19

104

+5V

Schematic diagram of the sensor system

Electronic Circuit of Magnetic Sensor

R20

R

R21

R

-

+

U5AD797

3

26

74

U6

D1

S12

GND3

+VCC4VCC5

IN6

-VCC7

S28

C41

R13

R26

R18

R25

R2210 Ω

R16

R14

R17

10 k

R15

R27

R32

R28

R33

R29

R34

5 k

R30

C29

C37

104

C32473

C39473C40

104

C33

104

C21

104C23

104

C25

104

C26

104

C30

104

C31

104

C35

104

C36

104

C27

104

C28

104

C34

104

C38

104

D3

DIODE

L1

1

2

L2

1

2

L3

1

2

4

-

+

U-4A

4

13

2

-

+

U-4B

75

6

8

-

+

U-5A

4

13

2

-

+

U-5B

75

6

8

-

+

U-6A

4

13

2

-

+

U-6B

75

6

8

C22

104

-5V

+5V

+5V

+5V

+5V

+5V

+5V

U7

D1

S12

GND3

+VCC4

VCC5

IN6

-VCC7

S28

+5V

-5V

-5V

-5V

-5V

-5V

-5V

-5V

-5V

R19

R24

R

R23

R

C24

OUT(X)

OUT(Y)

R1

20 kR210 k

R3

20 kR410 k

C1

104

C8

104

REF43

OUT(X)

OUT(Y)

REF43

U2

+Vcc1

CH02

CH13

CH24

CH35

COMM6

SHDN7

Vref8

+Vcc9

GND10

GND11

DOUT12BUSY13DIN14CS15

DIN16

-

+

U-1A

13

2

8

-

+

U-1B

4

75

6

C410 uF

C5104

DOUT

C210uF

C6104

C3104

DCLK

C7104

DIN

C10

01uF

CS

BUSY

C14 10uF

J1

CON6

123456

D1

DIODE

R5

47K

C9

10uF

C1310uF

Y1

OSC

OUT3

GND2

VCC4

U3

RSTVPP1

GND10

VCC20

XTAL15

XTAL24

P10AIN012P11AIN113P1214P1315P1416P1517P1618P1719

P30RXD2

P31TXD3

P32INT06

P33INT17

P34T08

P35T19

P3711

U4

C1+1

C1-3

C2+4

C2-5

VCC16

GND15

V+2

V-6

R1OUT12

R2OUT9

T1IN11

T2IN10

R1IN13

R2IN8

T1OUT14

T2OUT7

C12 10uF

C16

01uF

C15 10uF

C11

01uF

-5V

+5V

+5V

+5V

+5V

+5V

+5V

+5V

RST

OSC

OSC

RST

DCLKCSDINBUSYDOUT

U1

IN2

GND

4

OUT6

TEMP3

TRIM5

-5V

+5V

Electronic circuit diagram of the magnetic sensor

Photograph of the completed measuring system data acquisition

software in PC and probe scanning system

Experimental Setup for Magnetic Sensor

Reference material Scanning System Software LabVIEW

Reference Material (1) Normal defects and PVCs

Longitudinal and transverse defects

Def W L D Remarks

1 02 500 0213 (20 ) Inner defects

2 02 500 0427 (40 )

3 02 500 0213 (20 )Outer defectsPVC(1018)4 02 500 0427 (40 )

5 02 500 0639 (60 )

6 02 500 0852 (80 )

7 02 500 0639 (60 ) Inner defects

8 02 500 0852 (80 )

- 1 and 2 are inner defects

- 345 and 6 are outer defects with PVC

- 7 and 8 are inner defects

PVC

PVC

Defect Defect

For longitudinal defects and PVC For circumferential defects and PVC

ECT is very difficult to detect circumferential defects

We can distinguish PVCs and defects and longitudinal and circumferential defects

Flux-gate Magnetometer

One core sensor Two core sensor

3-축 flux-gate Magnetometer의 계략도

Sensorpia Co

pro

cess

or(

AV

R)

Sensor 1

RS422

Interface

Mic

ro-p

roce

ssor(

AV

R)

Sensor 2

Sensor 3

Interface

조립된 마그네토미터의 사진

Sensorpia Co

Analog PCB

Digital PCB

Sensorpia Co선형도(linearity)

10

20

30

40

50

60

y-axis

Magnetometer Output (microT)

-60 -50 -40 -30 -20 -10 0 10 20 30 40 50 60

-60

-50

-40

-30

-20

-10

0

10

Y-axis y=099946 x+0015STD 106E-4

Magnetometer Output (

Applied Magnetic Field (microT)

마그네토미터의 noise 특성 Sensorpia Co

1

10

100

y-axis

Magnetometer noise (nT)

0 1 2 3 4 5 6

1E-4

1E-3

001

01

Magnetometer noise (nT)

Frequency (Hz)

Magnetometer for KoDSAT

-150 -100 -50 0 50 100 150

-15

-10

-5

0

5

10

15

Magnetic Moment (Am

2)

Current (mA)

After Thermal Cycle Test

Measured

Resistance 193 ohm

Photograph of Magnetic torquer

Photograph of KoDSAT

Photograph of

3-axis Fluxgate

Magnetometer

Photograph of Magnetic torquer

Application of magnetometer

Moon magnetic fieldmeasurement

Telescope with direction indication

Joule Effect (Magnetostriction)

ϕ2cosel

l=

∆

0=∆

+∆

+∆

b

b

a

a

l

l

Actuator using Terfenol-D

00

05

10

B (T)

800

1000

1200

1400

1600

Magnetostriction (ppm)

-100 -50 0 50 100

-10

-05

00

B (T)

H (kAm)

2 MPa

4 MPa

6 MPa

8 MPa

10 MPa

12 MPa

-100 -50 0 50 100

-200

0

200

400

600

Magnetostriction (ppm)

H (kAm)

2 MPa

4 MPa

6 MPa

8 MPa

10 MPa

12 MPa

600

700

800

900

1000

-4 -3 -2 -1 0 1 2 3 4

0

10

20

30

40

50

60

Displacement (m

icro meter)

I (A)

FIELD

9 kAm

12 kAm

16 kAm

20 kAm

24 kAm

38 kAm

-50 -40 -30 -20 -10 0 10 20 30 40 50

-100

0

100

200

300

400

500

L (PPM)

H (kAm)

9 kAm

12 kAm

16 kAm

20 kAm

24 kAm

38 kAm

Magnetostrictive displacement sensor

Hysteresis loops under

tensile stress σ

(a) Crystalline 68 NiFe

λs = +25 10-6

(b) crystalline pure Ni λs

= -35 10-6

Villari Effect ( Inverse of Joule Effect)

= -35 10-6

(c) amorphous Co-based

alloy

λs = -35 10-6

ϕσλ 2sin2

3sdotsdot= smeE

γ

Permeability depending on the stress

σλmicromicro

1

3

2

Y

J

so

s

r =

γ

Calculated magnetization curves under stress

Variation of magnetization curve by an applied

tensile force (Co-based amorphous alloy)

Alloy Requirement

Materials for magnetoelastic sensors

Why amorphous magnetic materials are important

Stress-strain curves of several materials

Coercivity and hardness of several materials

Principles of magnetoelastic sensors

Non-contact torque sensor

Principle of cross torductor torque

sensor and flux pattern of sensor

poles on the surface of a shaft

a) without and b)with torsional load

Equivalent magnetic circuit of

cross type torque sensor

Helices of principal tensile and compressive stress on the surface of

a shaft subjected to torsion [32] Correlated changes of permeability

are detected by four-branch yoke system with sensing coils 123

and 4 and a common excitation pole

Examples of torque sensors

Four-branch type torque sensor

heads Pole structures realized

by commercial multi-pole

ferrites 14 and 18 min in

diameter (diameter of sensor

h e a d 1 7 a n d 2 4 m m

respectively) respectively)

Principle of Ring Torductor torque transducer

(a b) Physical structure (c) evolution of the

shaft surface under the transducer poles A and BRing torductor for measuring

torque on ship propeller shafts

(shaft diameter ca 500 mm)

(Courtesy ASEA Brown

Boveri AG)

Principal designs of coaxial torque sensors

Schematic diagram of data processing

electronics of a torque sensor

Extensometer (a) Construction of strain sensing element using

amorphous ribbon wound core (b) configuration of lumped

windings

∆E effect of an amorphous FeNi-based

alloy (Fe40 Ni38 Mo4 B18) Hs saturation

field

Magnetically tunable delay line

Torque Sensors using Amorphous wire

Sixtus tonk효과(large Barkhausen효과)

Hysteresis loops of a Wiegand wire for different reset fields

Curie 온도 및Hopkinson효과

Relation between normalised

saturation polarisation and

normalised Curie temperature

Permeability of a Mn-Zn ferrite as

a function of temperature and field

strength

Conclusions

1) Magnetic sensor 는 자동차 공장자동화 항공우주 및 군사용으로많이 사용되고 있다

2) 새로운 소재개발은 자기센서의 성능개발에 직접적인 영향을 준다2) 새로운 소재개발은 자기센서의 성능개발에 직접적인 영향을 준다

3) 센서의 개발을 위해서는 다양한 전공지식이 요구된다

(물리학 재료공학 기계공학 전자공학)

4) 센서분야가 고부가가치를 창출하는 부품사업이다

5) 핵심부품을 생산하는 중소기업의 item으로도 적절하다

Inductive Flowmeters

)( Btimessdot= υqF

EqF sdot=BE times=υ

)(ds Btimes== υEU )(ds Btimes== υEU

)( Bd timessdot= υU

Bsdotsdotsdot= υdKU

Development of magnetic phase detection

sensor for steam generator tube

Dirac Son1 Kwan-Sang Ryu2 Duck-Gun Park3

1Hannam University Daejeon Rep of Korea2Korea Research Institute of Standards and Science Daejeon Rep of Korea3KoreaAtomic Energy Research Institute Daejeon Rep of Korea

Introduction

The layout of pressurized water reactor (PWR) components

Primary side Secondary side (non-radioactive side)(radioactive side)

The Structure of SG(Steam Generator)(degradation mechanism)

Secondary SidePrimary Side

SCC

A B

A-B

Steam outlet

Anti-vibration

SCC

Fretting

Wall thinning

IGA

U-bend

In commercial power plants SG- height up to 21 m - weight up to 800 tons - 2~4 sets of SG were installed - SG can contain from 3000 to

16000 tubes each about 20 mmin diameter

Primary coolant outlet Primary coolant inlet

Anti-vibrationbars

Tubesupportplate

Tubesheet

IGA

SCC

Pitting

SCC

Inside Tubesheet

Top of Tubesheet

by SSHwang of KAERI

Denting

Sludge pile

in diameter

The SGT is made of nickel basedInconel alloy which is composed of 75 Ni 165Cr and 815Fe

-Degradation mechanism corrosion pitting denting inter granular attack

-Inspection Eddy current Testing(ECT)

Permeability Variation Clusters (PVC)

(Ferro-magnetic phase)

-005

000

005

010

015

m (emug)

1-1

-002

000

002

004

006

008

m (emug)

1-2

-1000 -500 0 500 1000

-015

-010

-005

H ( Am )

-1000 -500 0 500 1000

-006

-004

-002

H ( Am )

The hystresis loop in the fragment of PVC parts of Kori-1 retired SG tube

-004

-002

000

002

004

006

M (emug)

Inconel 600 tested at RT

under tensile stress

1 2 3

4 5 6

7 8 9-004

-002

000

002

004

006

M(emug)

Inconel 600 Heat treated at

602 oC under tensile stress

1 2 3

How can we detect magnetic phase

(PVC)selectively from the flaws in SGT

-3000 -2000 -1000 0 1000 2000 3000

-006

H (Oe)

7 8 9

10 11 12

-3000 -2000 -1000 0 1000 2000 3000

-006

-004

H(Oe)

4 5 6

7 8 9

The hysteresis loop of the tensile tested specimen at room temperature (a) and tensile tested at high temperature (b)

The magnetic phase can be created under the high temperature andpressure conditions which is correspond to the stress corrosion crackingin the SG tube in the NPP(Bruemmer SM Charlot LA amp Henager CH (1988) Corrosion 782)

Principle of ECT

If we can separate magnetic phase selectively from the

flaws using magnetic sensor the reliability of EC in SGT

inspection will be greatly enhanced

Structure of the permeability

sensor

Dimension and photograph of U-shape

sensing yoke

Design of Magnetic Sensor for PVC

sensor sensing yoke

Photograph of the completed sensor front side (above) and rear side (bottom)

R11R12

R10

R8

R6

R9

R13

R7

R14

C18

1 n

C17

C20

C21

D2

DIODE

SIN COS

-

+

U-2A

4

13

2

-

+

U-2B

75

6

8

-

+

U-3A

13

2

8

+5VC19

104

+5V

Schematic diagram of the sensor system

Electronic Circuit of Magnetic Sensor

R20

R

R21

R

-

+

U5AD797

3

26

74

U6

D1

S12

GND3

+VCC4VCC5

IN6

-VCC7

S28

C41

R13

R26

R18

R25

R2210 Ω

R16

R14

R17

10 k

R15

R27

R32

R28

R33

R29

R34

5 k

R30

C29

C37

104

C32473

C39473C40

104

C33

104

C21

104C23

104

C25

104

C26

104

C30

104

C31

104

C35

104

C36

104

C27

104

C28

104

C34

104

C38

104

D3

DIODE

L1

1

2

L2

1

2

L3

1

2

4

-

+

U-4A

4

13

2

-

+

U-4B

75

6

8

-

+

U-5A

4

13

2

-

+

U-5B

75

6

8

-

+

U-6A

4

13

2

-

+

U-6B

75

6

8

C22

104

-5V

+5V

+5V

+5V

+5V

+5V

+5V

U7

D1

S12

GND3

+VCC4

VCC5

IN6

-VCC7

S28

+5V

-5V

-5V

-5V

-5V

-5V

-5V

-5V

-5V

R19

R24

R

R23

R

C24

OUT(X)

OUT(Y)

R1

20 kR210 k

R3

20 kR410 k

C1

104

C8

104

REF43

OUT(X)

OUT(Y)

REF43

U2

+Vcc1

CH02

CH13

CH24

CH35

COMM6

SHDN7

Vref8

+Vcc9

GND10

GND11

DOUT12BUSY13DIN14CS15

DIN16

-

+

U-1A

13

2

8

-

+

U-1B

4

75

6

C410 uF

C5104

DOUT

C210uF

C6104

C3104

DCLK

C7104

DIN

C10

01uF

CS

BUSY

C14 10uF

J1

CON6

123456

D1

DIODE

R5

47K

C9

10uF

C1310uF

Y1

OSC

OUT3

GND2

VCC4

U3

RSTVPP1

GND10

VCC20

XTAL15

XTAL24

P10AIN012P11AIN113P1214P1315P1416P1517P1618P1719

P30RXD2

P31TXD3

P32INT06

P33INT17

P34T08

P35T19

P3711

U4

C1+1

C1-3

C2+4

C2-5

VCC16

GND15

V+2

V-6

R1OUT12

R2OUT9

T1IN11

T2IN10

R1IN13

R2IN8

T1OUT14

T2OUT7

C12 10uF

C16

01uF

C15 10uF

C11

01uF

-5V

+5V

+5V

+5V

+5V

+5V

+5V

+5V

RST

OSC

OSC

RST

DCLKCSDINBUSYDOUT

U1

IN2

GND

4

OUT6

TEMP3

TRIM5

-5V

+5V

Electronic circuit diagram of the magnetic sensor

Photograph of the completed measuring system data acquisition

software in PC and probe scanning system

Experimental Setup for Magnetic Sensor

Reference material Scanning System Software LabVIEW

Reference Material (1) Normal defects and PVCs

Longitudinal and transverse defects

Def W L D Remarks

1 02 500 0213 (20 ) Inner defects

2 02 500 0427 (40 )

3 02 500 0213 (20 )Outer defectsPVC(1018)4 02 500 0427 (40 )

5 02 500 0639 (60 )

6 02 500 0852 (80 )

7 02 500 0639 (60 ) Inner defects

8 02 500 0852 (80 )

- 1 and 2 are inner defects

- 345 and 6 are outer defects with PVC

- 7 and 8 are inner defects

PVC

PVC

Defect Defect

For longitudinal defects and PVC For circumferential defects and PVC

ECT is very difficult to detect circumferential defects

We can distinguish PVCs and defects and longitudinal and circumferential defects

Flux-gate Magnetometer

One core sensor Two core sensor

3-축 flux-gate Magnetometer의 계략도

Sensorpia Co

pro

cess

or(

AV

R)

Sensor 1

RS422

Interface

Mic

ro-p

roce

ssor(

AV

R)

Sensor 2

Sensor 3

Interface

조립된 마그네토미터의 사진

Sensorpia Co

Analog PCB

Digital PCB

Sensorpia Co선형도(linearity)

10

20

30

40

50

60

y-axis

Magnetometer Output (microT)

-60 -50 -40 -30 -20 -10 0 10 20 30 40 50 60

-60

-50

-40

-30

-20

-10

0

10

Y-axis y=099946 x+0015STD 106E-4

Magnetometer Output (

Applied Magnetic Field (microT)

마그네토미터의 noise 특성 Sensorpia Co

1

10

100

y-axis

Magnetometer noise (nT)

0 1 2 3 4 5 6

1E-4

1E-3

001

01

Magnetometer noise (nT)

Frequency (Hz)

Magnetometer for KoDSAT

-150 -100 -50 0 50 100 150

-15

-10

-5

0

5

10

15

Magnetic Moment (Am

2)

Current (mA)

After Thermal Cycle Test

Measured

Resistance 193 ohm

Photograph of Magnetic torquer

Photograph of KoDSAT

Photograph of

3-axis Fluxgate

Magnetometer

Photograph of Magnetic torquer

Application of magnetometer

Moon magnetic fieldmeasurement

Telescope with direction indication

Joule Effect (Magnetostriction)

ϕ2cosel

l=

∆

0=∆

+∆

+∆

b

b

a

a

l

l

Actuator using Terfenol-D

00

05

10

B (T)

800

1000

1200

1400

1600

Magnetostriction (ppm)

-100 -50 0 50 100

-10

-05

00

B (T)

H (kAm)

2 MPa

4 MPa

6 MPa

8 MPa

10 MPa

12 MPa

-100 -50 0 50 100

-200

0

200

400

600

Magnetostriction (ppm)

H (kAm)

2 MPa

4 MPa

6 MPa

8 MPa

10 MPa

12 MPa

600

700

800

900

1000

-4 -3 -2 -1 0 1 2 3 4

0

10

20

30

40

50

60

Displacement (m

icro meter)

I (A)

FIELD

9 kAm

12 kAm

16 kAm

20 kAm

24 kAm

38 kAm

-50 -40 -30 -20 -10 0 10 20 30 40 50

-100

0

100

200

300

400

500

L (PPM)

H (kAm)

9 kAm

12 kAm

16 kAm

20 kAm

24 kAm

38 kAm

Magnetostrictive displacement sensor

Hysteresis loops under

tensile stress σ

(a) Crystalline 68 NiFe

λs = +25 10-6

(b) crystalline pure Ni λs

= -35 10-6

Villari Effect ( Inverse of Joule Effect)

= -35 10-6

(c) amorphous Co-based

alloy

λs = -35 10-6

ϕσλ 2sin2

3sdotsdot= smeE

γ

Permeability depending on the stress

σλmicromicro

1

3

2

Y

J

so

s

r =

γ

Calculated magnetization curves under stress

Variation of magnetization curve by an applied

tensile force (Co-based amorphous alloy)

Alloy Requirement

Materials for magnetoelastic sensors

Why amorphous magnetic materials are important

Stress-strain curves of several materials

Coercivity and hardness of several materials

Principles of magnetoelastic sensors

Non-contact torque sensor

Principle of cross torductor torque

sensor and flux pattern of sensor

poles on the surface of a shaft

a) without and b)with torsional load

Equivalent magnetic circuit of

cross type torque sensor

Helices of principal tensile and compressive stress on the surface of

a shaft subjected to torsion [32] Correlated changes of permeability

are detected by four-branch yoke system with sensing coils 123

and 4 and a common excitation pole

Examples of torque sensors

Four-branch type torque sensor

heads Pole structures realized

by commercial multi-pole

ferrites 14 and 18 min in

diameter (diameter of sensor

h e a d 1 7 a n d 2 4 m m

respectively) respectively)

Principle of Ring Torductor torque transducer

(a b) Physical structure (c) evolution of the

shaft surface under the transducer poles A and BRing torductor for measuring

torque on ship propeller shafts

(shaft diameter ca 500 mm)

(Courtesy ASEA Brown

Boveri AG)

Principal designs of coaxial torque sensors

Schematic diagram of data processing

electronics of a torque sensor

Extensometer (a) Construction of strain sensing element using

amorphous ribbon wound core (b) configuration of lumped

windings

∆E effect of an amorphous FeNi-based

alloy (Fe40 Ni38 Mo4 B18) Hs saturation

field

Magnetically tunable delay line

Torque Sensors using Amorphous wire

Sixtus tonk효과(large Barkhausen효과)

Hysteresis loops of a Wiegand wire for different reset fields

Curie 온도 및Hopkinson효과

Relation between normalised

saturation polarisation and

normalised Curie temperature

Permeability of a Mn-Zn ferrite as

a function of temperature and field

strength

Conclusions

1) Magnetic sensor 는 자동차 공장자동화 항공우주 및 군사용으로많이 사용되고 있다

2) 새로운 소재개발은 자기센서의 성능개발에 직접적인 영향을 준다2) 새로운 소재개발은 자기센서의 성능개발에 직접적인 영향을 준다

3) 센서의 개발을 위해서는 다양한 전공지식이 요구된다

(물리학 재료공학 기계공학 전자공학)

4) 센서분야가 고부가가치를 창출하는 부품사업이다

5) 핵심부품을 생산하는 중소기업의 item으로도 적절하다

Development of magnetic phase detection

sensor for steam generator tube

Dirac Son1 Kwan-Sang Ryu2 Duck-Gun Park3

1Hannam University Daejeon Rep of Korea2Korea Research Institute of Standards and Science Daejeon Rep of Korea3KoreaAtomic Energy Research Institute Daejeon Rep of Korea

Introduction

The layout of pressurized water reactor (PWR) components

Primary side Secondary side (non-radioactive side)(radioactive side)

The Structure of SG(Steam Generator)(degradation mechanism)

Secondary SidePrimary Side

SCC

A B

A-B

Steam outlet

Anti-vibration

SCC

Fretting

Wall thinning

IGA

U-bend

In commercial power plants SG- height up to 21 m - weight up to 800 tons - 2~4 sets of SG were installed - SG can contain from 3000 to

16000 tubes each about 20 mmin diameter

Primary coolant outlet Primary coolant inlet

Anti-vibrationbars

Tubesupportplate

Tubesheet

IGA

SCC

Pitting

SCC

Inside Tubesheet

Top of Tubesheet

by SSHwang of KAERI

Denting

Sludge pile

in diameter

The SGT is made of nickel basedInconel alloy which is composed of 75 Ni 165Cr and 815Fe

-Degradation mechanism corrosion pitting denting inter granular attack

-Inspection Eddy current Testing(ECT)

Permeability Variation Clusters (PVC)

(Ferro-magnetic phase)

-005

000

005

010

015

m (emug)

1-1

-002

000

002

004

006

008

m (emug)

1-2

-1000 -500 0 500 1000

-015

-010

-005

H ( Am )

-1000 -500 0 500 1000

-006

-004

-002

H ( Am )

The hystresis loop in the fragment of PVC parts of Kori-1 retired SG tube

-004

-002

000

002

004

006

M (emug)

Inconel 600 tested at RT

under tensile stress

1 2 3

4 5 6

7 8 9-004

-002

000

002

004

006

M(emug)

Inconel 600 Heat treated at

602 oC under tensile stress

1 2 3

How can we detect magnetic phase

(PVC)selectively from the flaws in SGT

-3000 -2000 -1000 0 1000 2000 3000

-006

H (Oe)

7 8 9

10 11 12

-3000 -2000 -1000 0 1000 2000 3000

-006

-004

H(Oe)

4 5 6

7 8 9

The hysteresis loop of the tensile tested specimen at room temperature (a) and tensile tested at high temperature (b)

The magnetic phase can be created under the high temperature andpressure conditions which is correspond to the stress corrosion crackingin the SG tube in the NPP(Bruemmer SM Charlot LA amp Henager CH (1988) Corrosion 782)

Principle of ECT

If we can separate magnetic phase selectively from the

flaws using magnetic sensor the reliability of EC in SGT

inspection will be greatly enhanced

Structure of the permeability

sensor

Dimension and photograph of U-shape

sensing yoke

Design of Magnetic Sensor for PVC

sensor sensing yoke

Photograph of the completed sensor front side (above) and rear side (bottom)

R11R12

R10

R8

R6

R9

R13

R7

R14

C18

1 n

C17

C20

C21

D2

DIODE

SIN COS

-

+

U-2A

4

13

2

-

+

U-2B

75

6

8

-

+

U-3A

13

2

8

+5VC19

104

+5V

Schematic diagram of the sensor system

Electronic Circuit of Magnetic Sensor

R20

R

R21

R

-

+

U5AD797

3

26

74

U6

D1

S12

GND3

+VCC4VCC5

IN6

-VCC7

S28

C41

R13

R26

R18

R25

R2210 Ω

R16

R14

R17

10 k

R15

R27

R32

R28

R33

R29

R34

5 k

R30

C29

C37

104

C32473

C39473C40

104

C33

104

C21

104C23

104

C25

104

C26

104

C30

104

C31

104

C35

104

C36

104

C27

104

C28

104

C34

104

C38

104

D3

DIODE

L1

1

2

L2

1

2

L3

1

2

4

-

+

U-4A

4

13

2

-

+

U-4B

75

6

8

-

+

U-5A

4

13

2

-

+

U-5B

75

6

8

-

+

U-6A

4

13

2

-

+

U-6B

75

6

8

C22

104

-5V

+5V

+5V

+5V

+5V

+5V

+5V

U7

D1

S12

GND3

+VCC4

VCC5

IN6

-VCC7

S28

+5V

-5V

-5V

-5V

-5V

-5V

-5V

-5V

-5V

R19

R24

R

R23

R

C24

OUT(X)

OUT(Y)

R1

20 kR210 k

R3

20 kR410 k

C1

104

C8

104

REF43

OUT(X)

OUT(Y)

REF43

U2

+Vcc1

CH02

CH13

CH24

CH35

COMM6

SHDN7

Vref8

+Vcc9

GND10

GND11

DOUT12BUSY13DIN14CS15

DIN16

-

+

U-1A

13

2

8

-

+

U-1B

4

75

6

C410 uF

C5104

DOUT

C210uF

C6104

C3104

DCLK

C7104

DIN

C10

01uF

CS

BUSY

C14 10uF

J1

CON6

123456

D1

DIODE

R5

47K

C9

10uF

C1310uF

Y1

OSC

OUT3

GND2

VCC4

U3

RSTVPP1

GND10

VCC20

XTAL15

XTAL24

P10AIN012P11AIN113P1214P1315P1416P1517P1618P1719

P30RXD2

P31TXD3

P32INT06

P33INT17

P34T08

P35T19

P3711

U4

C1+1

C1-3

C2+4

C2-5

VCC16

GND15

V+2

V-6

R1OUT12

R2OUT9

T1IN11

T2IN10

R1IN13

R2IN8

T1OUT14

T2OUT7

C12 10uF

C16

01uF

C15 10uF

C11

01uF

-5V

+5V

+5V

+5V

+5V

+5V

+5V

+5V

RST

OSC

OSC

RST

DCLKCSDINBUSYDOUT

U1

IN2

GND

4

OUT6

TEMP3

TRIM5

-5V

+5V

Electronic circuit diagram of the magnetic sensor

Photograph of the completed measuring system data acquisition

software in PC and probe scanning system

Experimental Setup for Magnetic Sensor

Reference material Scanning System Software LabVIEW

Reference Material (1) Normal defects and PVCs

Longitudinal and transverse defects

Def W L D Remarks

1 02 500 0213 (20 ) Inner defects

2 02 500 0427 (40 )

3 02 500 0213 (20 )Outer defectsPVC(1018)4 02 500 0427 (40 )

5 02 500 0639 (60 )

6 02 500 0852 (80 )

7 02 500 0639 (60 ) Inner defects

8 02 500 0852 (80 )

- 1 and 2 are inner defects

- 345 and 6 are outer defects with PVC

- 7 and 8 are inner defects

PVC

PVC

Defect Defect

For longitudinal defects and PVC For circumferential defects and PVC

ECT is very difficult to detect circumferential defects

We can distinguish PVCs and defects and longitudinal and circumferential defects

Flux-gate Magnetometer

One core sensor Two core sensor

3-축 flux-gate Magnetometer의 계략도

Sensorpia Co

pro

cess

or(

AV

R)

Sensor 1

RS422

Interface

Mic

ro-p

roce

ssor(

AV

R)

Sensor 2

Sensor 3

Interface

조립된 마그네토미터의 사진

Sensorpia Co

Analog PCB

Digital PCB

Sensorpia Co선형도(linearity)

10

20

30

40

50

60

y-axis

Magnetometer Output (microT)

-60 -50 -40 -30 -20 -10 0 10 20 30 40 50 60

-60

-50

-40

-30

-20

-10

0

10

Y-axis y=099946 x+0015STD 106E-4

Magnetometer Output (

Applied Magnetic Field (microT)

마그네토미터의 noise 특성 Sensorpia Co

1

10

100

y-axis

Magnetometer noise (nT)

0 1 2 3 4 5 6

1E-4

1E-3

001

01

Magnetometer noise (nT)

Frequency (Hz)

Magnetometer for KoDSAT

-150 -100 -50 0 50 100 150

-15

-10

-5

0

5

10

15

Magnetic Moment (Am

2)

Current (mA)

After Thermal Cycle Test

Measured

Resistance 193 ohm

Photograph of Magnetic torquer

Photograph of KoDSAT

Photograph of

3-axis Fluxgate

Magnetometer

Photograph of Magnetic torquer

Application of magnetometer

Moon magnetic fieldmeasurement

Telescope with direction indication

Joule Effect (Magnetostriction)

ϕ2cosel

l=

∆

0=∆

+∆

+∆

b

b

a

a

l

l

Actuator using Terfenol-D

00

05

10

B (T)

800

1000

1200

1400

1600

Magnetostriction (ppm)

-100 -50 0 50 100

-10

-05

00

B (T)

H (kAm)

2 MPa

4 MPa

6 MPa

8 MPa

10 MPa

12 MPa

-100 -50 0 50 100

-200

0

200

400

600

Magnetostriction (ppm)

H (kAm)

2 MPa

4 MPa

6 MPa

8 MPa

10 MPa

12 MPa

600

700

800

900

1000

-4 -3 -2 -1 0 1 2 3 4

0

10

20

30

40

50

60

Displacement (m

icro meter)

I (A)

FIELD

9 kAm

12 kAm

16 kAm

20 kAm

24 kAm

38 kAm

-50 -40 -30 -20 -10 0 10 20 30 40 50

-100

0

100

200

300

400

500

L (PPM)

H (kAm)

9 kAm

12 kAm

16 kAm

20 kAm

24 kAm

38 kAm

Magnetostrictive displacement sensor

Hysteresis loops under

tensile stress σ

(a) Crystalline 68 NiFe

λs = +25 10-6

(b) crystalline pure Ni λs

= -35 10-6

Villari Effect ( Inverse of Joule Effect)

= -35 10-6

(c) amorphous Co-based

alloy

λs = -35 10-6

ϕσλ 2sin2

3sdotsdot= smeE

γ

Permeability depending on the stress

σλmicromicro

1

3

2

Y

J

so

s

r =

γ

Calculated magnetization curves under stress

Variation of magnetization curve by an applied

tensile force (Co-based amorphous alloy)

Alloy Requirement

Materials for magnetoelastic sensors

Why amorphous magnetic materials are important

Stress-strain curves of several materials

Coercivity and hardness of several materials

Principles of magnetoelastic sensors

Non-contact torque sensor

Principle of cross torductor torque

sensor and flux pattern of sensor

poles on the surface of a shaft

a) without and b)with torsional load

Equivalent magnetic circuit of

cross type torque sensor

Helices of principal tensile and compressive stress on the surface of

a shaft subjected to torsion [32] Correlated changes of permeability

are detected by four-branch yoke system with sensing coils 123

and 4 and a common excitation pole

Examples of torque sensors

Four-branch type torque sensor

heads Pole structures realized

by commercial multi-pole

ferrites 14 and 18 min in

diameter (diameter of sensor

h e a d 1 7 a n d 2 4 m m

respectively) respectively)

Principle of Ring Torductor torque transducer

(a b) Physical structure (c) evolution of the

shaft surface under the transducer poles A and BRing torductor for measuring

torque on ship propeller shafts

(shaft diameter ca 500 mm)

(Courtesy ASEA Brown

Boveri AG)

Principal designs of coaxial torque sensors

Schematic diagram of data processing

electronics of a torque sensor

Extensometer (a) Construction of strain sensing element using

amorphous ribbon wound core (b) configuration of lumped

windings

∆E effect of an amorphous FeNi-based

alloy (Fe40 Ni38 Mo4 B18) Hs saturation

field

Magnetically tunable delay line

Torque Sensors using Amorphous wire

Sixtus tonk효과(large Barkhausen효과)

Hysteresis loops of a Wiegand wire for different reset fields

Curie 온도 및Hopkinson효과

Relation between normalised

saturation polarisation and

normalised Curie temperature

Permeability of a Mn-Zn ferrite as

a function of temperature and field

strength

Conclusions

1) Magnetic sensor 는 자동차 공장자동화 항공우주 및 군사용으로많이 사용되고 있다

2) 새로운 소재개발은 자기센서의 성능개발에 직접적인 영향을 준다2) 새로운 소재개발은 자기센서의 성능개발에 직접적인 영향을 준다

3) 센서의 개발을 위해서는 다양한 전공지식이 요구된다

(물리학 재료공학 기계공학 전자공학)

4) 센서분야가 고부가가치를 창출하는 부품사업이다

5) 핵심부품을 생산하는 중소기업의 item으로도 적절하다

Introduction

The layout of pressurized water reactor (PWR) components

Primary side Secondary side (non-radioactive side)(radioactive side)

The Structure of SG(Steam Generator)(degradation mechanism)

Secondary SidePrimary Side

SCC

A B

A-B

Steam outlet

Anti-vibration

SCC

Fretting

Wall thinning

IGA

U-bend

In commercial power plants SG- height up to 21 m - weight up to 800 tons - 2~4 sets of SG were installed - SG can contain from 3000 to

16000 tubes each about 20 mmin diameter

Primary coolant outlet Primary coolant inlet

Anti-vibrationbars

Tubesupportplate

Tubesheet

IGA

SCC

Pitting

SCC

Inside Tubesheet

Top of Tubesheet

by SSHwang of KAERI

Denting

Sludge pile

in diameter

The SGT is made of nickel basedInconel alloy which is composed of 75 Ni 165Cr and 815Fe

-Degradation mechanism corrosion pitting denting inter granular attack

-Inspection Eddy current Testing(ECT)

Permeability Variation Clusters (PVC)

(Ferro-magnetic phase)

-005

000

005

010

015

m (emug)

1-1

-002

000

002

004

006

008

m (emug)

1-2

-1000 -500 0 500 1000

-015

-010

-005

H ( Am )

-1000 -500 0 500 1000

-006

-004

-002

H ( Am )

The hystresis loop in the fragment of PVC parts of Kori-1 retired SG tube

-004

-002

000

002

004

006

M (emug)

Inconel 600 tested at RT

under tensile stress

1 2 3

4 5 6

7 8 9-004

-002

000

002

004

006

M(emug)

Inconel 600 Heat treated at

602 oC under tensile stress

1 2 3

How can we detect magnetic phase

(PVC)selectively from the flaws in SGT

-3000 -2000 -1000 0 1000 2000 3000

-006

H (Oe)

7 8 9

10 11 12

-3000 -2000 -1000 0 1000 2000 3000

-006

-004

H(Oe)

4 5 6

7 8 9

The hysteresis loop of the tensile tested specimen at room temperature (a) and tensile tested at high temperature (b)

The magnetic phase can be created under the high temperature andpressure conditions which is correspond to the stress corrosion crackingin the SG tube in the NPP(Bruemmer SM Charlot LA amp Henager CH (1988) Corrosion 782)

Principle of ECT

If we can separate magnetic phase selectively from the

flaws using magnetic sensor the reliability of EC in SGT

inspection will be greatly enhanced

Structure of the permeability

sensor

Dimension and photograph of U-shape

sensing yoke

Design of Magnetic Sensor for PVC

sensor sensing yoke

Photograph of the completed sensor front side (above) and rear side (bottom)

R11R12

R10

R8

R6

R9

R13

R7

R14

C18

1 n

C17

C20

C21

D2

DIODE

SIN COS

-

+

U-2A

4

13

2

-

+

U-2B

75

6

8

-

+

U-3A

13

2

8

+5VC19

104

+5V

Schematic diagram of the sensor system

Electronic Circuit of Magnetic Sensor

R20

R

R21

R

-

+

U5AD797

3

26

74

U6

D1

S12

GND3

+VCC4VCC5

IN6

-VCC7

S28

C41

R13

R26

R18

R25

R2210 Ω

R16

R14

R17

10 k

R15

R27

R32

R28

R33

R29

R34

5 k

R30

C29

C37

104

C32473

C39473C40

104

C33

104

C21

104C23

104

C25

104

C26

104

C30

104

C31

104

C35

104

C36

104

C27

104

C28

104

C34

104

C38

104

D3

DIODE

L1

1

2

L2

1

2

L3

1

2

4

-

+

U-4A

4

13

2

-

+

U-4B

75

6

8

-

+

U-5A

4

13

2

-

+

U-5B

75

6

8

-

+

U-6A

4

13

2

-

+

U-6B

75

6

8

C22

104

-5V

+5V

+5V

+5V

+5V

+5V

+5V

U7

D1

S12

GND3

+VCC4

VCC5

IN6

-VCC7

S28

+5V

-5V

-5V

-5V

-5V

-5V

-5V

-5V

-5V

R19

R24

R

R23

R

C24

OUT(X)

OUT(Y)

R1

20 kR210 k

R3

20 kR410 k

C1

104

C8

104

REF43

OUT(X)

OUT(Y)

REF43

U2

+Vcc1

CH02

CH13

CH24

CH35

COMM6

SHDN7

Vref8

+Vcc9

GND10

GND11

DOUT12BUSY13DIN14CS15

DIN16

-

+

U-1A

13

2

8

-

+

U-1B

4

75

6

C410 uF

C5104

DOUT

C210uF

C6104

C3104

DCLK

C7104

DIN

C10

01uF

CS

BUSY

C14 10uF

J1

CON6

123456

D1

DIODE

R5

47K

C9

10uF

C1310uF

Y1

OSC

OUT3

GND2

VCC4

U3

RSTVPP1

GND10

VCC20

XTAL15

XTAL24

P10AIN012P11AIN113P1214P1315P1416P1517P1618P1719

P30RXD2

P31TXD3

P32INT06

P33INT17

P34T08

P35T19

P3711

U4

C1+1

C1-3

C2+4

C2-5

VCC16

GND15

V+2

V-6

R1OUT12

R2OUT9

T1IN11

T2IN10

R1IN13

R2IN8

T1OUT14

T2OUT7

C12 10uF

C16

01uF

C15 10uF

C11

01uF

-5V

+5V

+5V

+5V

+5V

+5V

+5V

+5V

RST

OSC

OSC

RST

DCLKCSDINBUSYDOUT

U1

IN2

GND

4

OUT6

TEMP3

TRIM5

-5V

+5V

Electronic circuit diagram of the magnetic sensor

Photograph of the completed measuring system data acquisition

software in PC and probe scanning system

Experimental Setup for Magnetic Sensor

Reference material Scanning System Software LabVIEW

Reference Material (1) Normal defects and PVCs

Longitudinal and transverse defects

Def W L D Remarks

1 02 500 0213 (20 ) Inner defects

2 02 500 0427 (40 )

3 02 500 0213 (20 )Outer defectsPVC(1018)4 02 500 0427 (40 )

5 02 500 0639 (60 )

6 02 500 0852 (80 )

7 02 500 0639 (60 ) Inner defects

8 02 500 0852 (80 )

- 1 and 2 are inner defects

- 345 and 6 are outer defects with PVC

- 7 and 8 are inner defects

PVC

PVC

Defect Defect

For longitudinal defects and PVC For circumferential defects and PVC

ECT is very difficult to detect circumferential defects

We can distinguish PVCs and defects and longitudinal and circumferential defects

Flux-gate Magnetometer

One core sensor Two core sensor

3-축 flux-gate Magnetometer의 계략도

Sensorpia Co

pro

cess

or(

AV

R)

Sensor 1

RS422

Interface

Mic

ro-p

roce

ssor(

AV

R)

Sensor 2

Sensor 3

Interface

조립된 마그네토미터의 사진

Sensorpia Co

Analog PCB

Digital PCB

Sensorpia Co선형도(linearity)

10

20

30

40

50

60

y-axis

Magnetometer Output (microT)

-60 -50 -40 -30 -20 -10 0 10 20 30 40 50 60

-60

-50

-40

-30

-20

-10

0

10

Y-axis y=099946 x+0015STD 106E-4

Magnetometer Output (

Applied Magnetic Field (microT)

마그네토미터의 noise 특성 Sensorpia Co

1

10

100

y-axis

Magnetometer noise (nT)

0 1 2 3 4 5 6

1E-4

1E-3

001

01

Magnetometer noise (nT)

Frequency (Hz)

Magnetometer for KoDSAT

-150 -100 -50 0 50 100 150

-15

-10

-5

0

5

10

15

Magnetic Moment (Am

2)

Current (mA)

After Thermal Cycle Test

Measured

Resistance 193 ohm

Photograph of Magnetic torquer

Photograph of KoDSAT

Photograph of

3-axis Fluxgate

Magnetometer

Photograph of Magnetic torquer

Application of magnetometer

Moon magnetic fieldmeasurement

Telescope with direction indication

Joule Effect (Magnetostriction)

ϕ2cosel

l=

∆

0=∆

+∆

+∆

b

b

a

a

l

l

Actuator using Terfenol-D

00

05

10

B (T)

800

1000

1200

1400

1600

Magnetostriction (ppm)

-100 -50 0 50 100

-10

-05

00

B (T)

H (kAm)

2 MPa

4 MPa

6 MPa

8 MPa

10 MPa

12 MPa

-100 -50 0 50 100

-200

0

200

400

600

Magnetostriction (ppm)

H (kAm)

2 MPa

4 MPa

6 MPa

8 MPa

10 MPa

12 MPa

600

700

800

900

1000

-4 -3 -2 -1 0 1 2 3 4

0

10

20

30

40

50

60

Displacement (m

icro meter)

I (A)

FIELD

9 kAm

12 kAm

16 kAm

20 kAm

24 kAm

38 kAm

-50 -40 -30 -20 -10 0 10 20 30 40 50

-100

0

100

200

300

400

500

L (PPM)

H (kAm)

9 kAm

12 kAm

16 kAm

20 kAm

24 kAm

38 kAm

Magnetostrictive displacement sensor

Hysteresis loops under

tensile stress σ

(a) Crystalline 68 NiFe

λs = +25 10-6

(b) crystalline pure Ni λs

= -35 10-6

Villari Effect ( Inverse of Joule Effect)

= -35 10-6

(c) amorphous Co-based

alloy

λs = -35 10-6

ϕσλ 2sin2

3sdotsdot= smeE

γ

Permeability depending on the stress

σλmicromicro

1

3

2

Y

J

so

s

r =

γ

Calculated magnetization curves under stress

Variation of magnetization curve by an applied

tensile force (Co-based amorphous alloy)

Alloy Requirement

Materials for magnetoelastic sensors

Why amorphous magnetic materials are important

Stress-strain curves of several materials

Coercivity and hardness of several materials

Principles of magnetoelastic sensors

Non-contact torque sensor

Principle of cross torductor torque

sensor and flux pattern of sensor

poles on the surface of a shaft

a) without and b)with torsional load

Equivalent magnetic circuit of

cross type torque sensor

Helices of principal tensile and compressive stress on the surface of

a shaft subjected to torsion [32] Correlated changes of permeability

are detected by four-branch yoke system with sensing coils 123

and 4 and a common excitation pole

Examples of torque sensors

Four-branch type torque sensor

heads Pole structures realized

by commercial multi-pole

ferrites 14 and 18 min in

diameter (diameter of sensor

h e a d 1 7 a n d 2 4 m m

respectively) respectively)

Principle of Ring Torductor torque transducer

(a b) Physical structure (c) evolution of the

shaft surface under the transducer poles A and BRing torductor for measuring

torque on ship propeller shafts

(shaft diameter ca 500 mm)

(Courtesy ASEA Brown

Boveri AG)

Principal designs of coaxial torque sensors

Schematic diagram of data processing

electronics of a torque sensor

Extensometer (a) Construction of strain sensing element using

amorphous ribbon wound core (b) configuration of lumped

windings

∆E effect of an amorphous FeNi-based

alloy (Fe40 Ni38 Mo4 B18) Hs saturation

field

Magnetically tunable delay line

Torque Sensors using Amorphous wire

Sixtus tonk효과(large Barkhausen효과)

Hysteresis loops of a Wiegand wire for different reset fields

Curie 온도 및Hopkinson효과

Relation between normalised

saturation polarisation and

normalised Curie temperature

Permeability of a Mn-Zn ferrite as

a function of temperature and field

strength

Conclusions

1) Magnetic sensor 는 자동차 공장자동화 항공우주 및 군사용으로많이 사용되고 있다

2) 새로운 소재개발은 자기센서의 성능개발에 직접적인 영향을 준다2) 새로운 소재개발은 자기센서의 성능개발에 직접적인 영향을 준다

3) 센서의 개발을 위해서는 다양한 전공지식이 요구된다

(물리학 재료공학 기계공학 전자공학)

4) 센서분야가 고부가가치를 창출하는 부품사업이다

5) 핵심부품을 생산하는 중소기업의 item으로도 적절하다

The Structure of SG(Steam Generator)(degradation mechanism)

Secondary SidePrimary Side

SCC

A B

A-B

Steam outlet

Anti-vibration

SCC

Fretting

Wall thinning

IGA

U-bend

In commercial power plants SG- height up to 21 m - weight up to 800 tons - 2~4 sets of SG were installed - SG can contain from 3000 to

16000 tubes each about 20 mmin diameter

Primary coolant outlet Primary coolant inlet

Anti-vibrationbars

Tubesupportplate

Tubesheet

IGA

SCC

Pitting

SCC

Inside Tubesheet

Top of Tubesheet

by SSHwang of KAERI

Denting

Sludge pile

in diameter

The SGT is made of nickel basedInconel alloy which is composed of 75 Ni 165Cr and 815Fe

-Degradation mechanism corrosion pitting denting inter granular attack

-Inspection Eddy current Testing(ECT)

Permeability Variation Clusters (PVC)

(Ferro-magnetic phase)

-005

000

005

010

015

m (emug)

1-1

-002

000

002

004

006

008

m (emug)

1-2

-1000 -500 0 500 1000

-015

-010

-005

H ( Am )

-1000 -500 0 500 1000

-006

-004

-002

H ( Am )

The hystresis loop in the fragment of PVC parts of Kori-1 retired SG tube

-004

-002

000

002

004

006

M (emug)

Inconel 600 tested at RT

under tensile stress

1 2 3

4 5 6

7 8 9-004

-002

000

002

004

006

M(emug)

Inconel 600 Heat treated at

602 oC under tensile stress

1 2 3

How can we detect magnetic phase

(PVC)selectively from the flaws in SGT

-3000 -2000 -1000 0 1000 2000 3000

-006

H (Oe)

7 8 9

10 11 12

-3000 -2000 -1000 0 1000 2000 3000

-006

-004

H(Oe)

4 5 6

7 8 9

The hysteresis loop of the tensile tested specimen at room temperature (a) and tensile tested at high temperature (b)

The magnetic phase can be created under the high temperature andpressure conditions which is correspond to the stress corrosion crackingin the SG tube in the NPP(Bruemmer SM Charlot LA amp Henager CH (1988) Corrosion 782)

Principle of ECT

If we can separate magnetic phase selectively from the

flaws using magnetic sensor the reliability of EC in SGT

inspection will be greatly enhanced

Structure of the permeability

sensor

Dimension and photograph of U-shape

sensing yoke

Design of Magnetic Sensor for PVC

sensor sensing yoke

Photograph of the completed sensor front side (above) and rear side (bottom)

R11R12

R10

R8

R6

R9

R13

R7

R14

C18

1 n

C17

C20

C21

D2

DIODE

SIN COS

-

+

U-2A

4

13

2

-

+

U-2B

75

6

8

-

+

U-3A

13

2

8

+5VC19

104

+5V

Schematic diagram of the sensor system

Electronic Circuit of Magnetic Sensor

R20

R

R21

R

-

+

U5AD797

3

26

74

U6

D1

S12

GND3

+VCC4VCC5

IN6

-VCC7

S28

C41

R13

R26

R18

R25

R2210 Ω

R16

R14

R17

10 k

R15

R27

R32

R28

R33

R29

R34

5 k

R30

C29

C37

104

C32473

C39473C40

104

C33

104

C21

104C23

104

C25

104

C26

104

C30

104

C31

104

C35

104

C36

104

C27

104

C28

104

C34

104

C38

104

D3

DIODE

L1

1

2

L2

1

2

L3

1

2

4

-

+

U-4A

4

13

2

-

+

U-4B

75

6

8

-

+

U-5A

4

13

2

-

+

U-5B

75

6

8

-

+

U-6A

4

13

2

-

+

U-6B

75

6

8

C22

104

-5V

+5V

+5V

+5V

+5V

+5V

+5V

U7

D1

S12

GND3

+VCC4

VCC5

IN6

-VCC7

S28

+5V

-5V

-5V

-5V

-5V

-5V

-5V

-5V

-5V

R19

R24

R

R23

R

C24

OUT(X)

OUT(Y)

R1

20 kR210 k

R3

20 kR410 k

C1

104

C8

104

REF43

OUT(X)

OUT(Y)

REF43

U2

+Vcc1

CH02

CH13

CH24

CH35

COMM6

SHDN7

Vref8

+Vcc9

GND10

GND11

DOUT12BUSY13DIN14CS15

DIN16

-

+

U-1A

13

2

8

-

+

U-1B

4

75

6

C410 uF

C5104

DOUT

C210uF

C6104

C3104

DCLK

C7104

DIN

C10

01uF

CS

BUSY

C14 10uF

J1

CON6

123456

D1

DIODE

R5

47K

C9

10uF

C1310uF

Y1

OSC

OUT3

GND2

VCC4

U3

RSTVPP1

GND10

VCC20

XTAL15

XTAL24

P10AIN012P11AIN113P1214P1315P1416P1517P1618P1719

P30RXD2

P31TXD3

P32INT06

P33INT17

P34T08

P35T19

P3711

U4

C1+1

C1-3

C2+4

C2-5

VCC16

GND15

V+2

V-6

R1OUT12

R2OUT9

T1IN11

T2IN10

R1IN13

R2IN8

T1OUT14

T2OUT7

C12 10uF

C16

01uF

C15 10uF

C11

01uF

-5V

+5V

+5V

+5V

+5V

+5V

+5V

+5V

RST

OSC

OSC

RST

DCLKCSDINBUSYDOUT

U1

IN2

GND

4

OUT6

TEMP3

TRIM5

-5V

+5V

Electronic circuit diagram of the magnetic sensor

Photograph of the completed measuring system data acquisition

software in PC and probe scanning system

Experimental Setup for Magnetic Sensor

Reference material Scanning System Software LabVIEW

Reference Material (1) Normal defects and PVCs

Longitudinal and transverse defects

Def W L D Remarks

1 02 500 0213 (20 ) Inner defects

2 02 500 0427 (40 )

3 02 500 0213 (20 )Outer defectsPVC(1018)4 02 500 0427 (40 )

5 02 500 0639 (60 )

6 02 500 0852 (80 )

7 02 500 0639 (60 ) Inner defects

8 02 500 0852 (80 )

- 1 and 2 are inner defects

- 345 and 6 are outer defects with PVC

- 7 and 8 are inner defects

PVC

PVC

Defect Defect

For longitudinal defects and PVC For circumferential defects and PVC

ECT is very difficult to detect circumferential defects

We can distinguish PVCs and defects and longitudinal and circumferential defects

Flux-gate Magnetometer

One core sensor Two core sensor

3-축 flux-gate Magnetometer의 계략도

Sensorpia Co

pro

cess

or(

AV

R)

Sensor 1

RS422

Interface

Mic

ro-p

roce

ssor(

AV

R)

Sensor 2

Sensor 3

Interface

조립된 마그네토미터의 사진

Sensorpia Co

Analog PCB

Digital PCB

Sensorpia Co선형도(linearity)

10

20

30

40

50

60

y-axis

Magnetometer Output (microT)

-60 -50 -40 -30 -20 -10 0 10 20 30 40 50 60

-60

-50

-40

-30

-20

-10

0

10

Y-axis y=099946 x+0015STD 106E-4

Magnetometer Output (

Applied Magnetic Field (microT)

마그네토미터의 noise 특성 Sensorpia Co

1

10

100

y-axis

Magnetometer noise (nT)

0 1 2 3 4 5 6

1E-4

1E-3

001

01

Magnetometer noise (nT)

Frequency (Hz)

Magnetometer for KoDSAT

-150 -100 -50 0 50 100 150

-15

-10

-5

0

5

10

15

Magnetic Moment (Am

2)

Current (mA)

After Thermal Cycle Test

Measured

Resistance 193 ohm

Photograph of Magnetic torquer

Photograph of KoDSAT

Photograph of

3-axis Fluxgate

Magnetometer

Photograph of Magnetic torquer

Application of magnetometer

Moon magnetic fieldmeasurement

Telescope with direction indication

Joule Effect (Magnetostriction)

ϕ2cosel

l=

∆

0=∆

+∆

+∆

b

b

a

a

l

l

Actuator using Terfenol-D

00

05

10

B (T)

800

1000

1200

1400

1600

Magnetostriction (ppm)

-100 -50 0 50 100

-10

-05

00

B (T)

H (kAm)

2 MPa

4 MPa

6 MPa

8 MPa

10 MPa

12 MPa

-100 -50 0 50 100

-200

0

200

400

600

Magnetostriction (ppm)

H (kAm)

2 MPa

4 MPa

6 MPa

8 MPa

10 MPa

12 MPa

600

700

800

900

1000

-4 -3 -2 -1 0 1 2 3 4

0

10

20

30

40

50

60

Displacement (m

icro meter)

I (A)

FIELD

9 kAm

12 kAm

16 kAm

20 kAm

24 kAm

38 kAm

-50 -40 -30 -20 -10 0 10 20 30 40 50

-100

0

100

200

300

400

500

L (PPM)

H (kAm)

9 kAm

12 kAm

16 kAm

20 kAm

24 kAm

38 kAm

Magnetostrictive displacement sensor

Hysteresis loops under

tensile stress σ

(a) Crystalline 68 NiFe

λs = +25 10-6

(b) crystalline pure Ni λs

= -35 10-6

Villari Effect ( Inverse of Joule Effect)

= -35 10-6

(c) amorphous Co-based

alloy

λs = -35 10-6

ϕσλ 2sin2

3sdotsdot= smeE

γ

Permeability depending on the stress

σλmicromicro

1

3

2

Y

J

so

s

r =

γ

Calculated magnetization curves under stress

Variation of magnetization curve by an applied

tensile force (Co-based amorphous alloy)

Alloy Requirement

Materials for magnetoelastic sensors

Why amorphous magnetic materials are important

Stress-strain curves of several materials

Coercivity and hardness of several materials

Principles of magnetoelastic sensors

Non-contact torque sensor

Principle of cross torductor torque

sensor and flux pattern of sensor

poles on the surface of a shaft

a) without and b)with torsional load

Equivalent magnetic circuit of

cross type torque sensor

Helices of principal tensile and compressive stress on the surface of

a shaft subjected to torsion [32] Correlated changes of permeability

are detected by four-branch yoke system with sensing coils 123

and 4 and a common excitation pole

Examples of torque sensors

Four-branch type torque sensor

heads Pole structures realized

by commercial multi-pole

ferrites 14 and 18 min in

diameter (diameter of sensor

h e a d 1 7 a n d 2 4 m m

respectively) respectively)

Principle of Ring Torductor torque transducer

(a b) Physical structure (c) evolution of the

shaft surface under the transducer poles A and BRing torductor for measuring

torque on ship propeller shafts

(shaft diameter ca 500 mm)

(Courtesy ASEA Brown

Boveri AG)

Principal designs of coaxial torque sensors

Schematic diagram of data processing

electronics of a torque sensor

Extensometer (a) Construction of strain sensing element using

amorphous ribbon wound core (b) configuration of lumped

windings

∆E effect of an amorphous FeNi-based

alloy (Fe40 Ni38 Mo4 B18) Hs saturation

field

Magnetically tunable delay line

Torque Sensors using Amorphous wire

Sixtus tonk효과(large Barkhausen효과)

Hysteresis loops of a Wiegand wire for different reset fields

Curie 온도 및Hopkinson효과

Relation between normalised

saturation polarisation and

normalised Curie temperature

Permeability of a Mn-Zn ferrite as

a function of temperature and field

strength

Conclusions

1) Magnetic sensor 는 자동차 공장자동화 항공우주 및 군사용으로많이 사용되고 있다

2) 새로운 소재개발은 자기센서의 성능개발에 직접적인 영향을 준다2) 새로운 소재개발은 자기센서의 성능개발에 직접적인 영향을 준다

3) 센서의 개발을 위해서는 다양한 전공지식이 요구된다

(물리학 재료공학 기계공학 전자공학)

4) 센서분야가 고부가가치를 창출하는 부품사업이다

5) 핵심부품을 생산하는 중소기업의 item으로도 적절하다

Permeability Variation Clusters (PVC)

(Ferro-magnetic phase)

-005

000

005

010

015

m (emug)

1-1

-002

000

002

004

006

008

m (emug)

1-2

-1000 -500 0 500 1000

-015

-010

-005

H ( Am )

-1000 -500 0 500 1000

-006

-004

-002

H ( Am )

The hystresis loop in the fragment of PVC parts of Kori-1 retired SG tube

-004

-002

000

002

004

006

M (emug)

Inconel 600 tested at RT

under tensile stress

1 2 3

4 5 6

7 8 9-004

-002

000

002

004

006

M(emug)

Inconel 600 Heat treated at

602 oC under tensile stress

1 2 3

How can we detect magnetic phase

(PVC)selectively from the flaws in SGT

-3000 -2000 -1000 0 1000 2000 3000

-006

H (Oe)

7 8 9

10 11 12

-3000 -2000 -1000 0 1000 2000 3000

-006

-004

H(Oe)

4 5 6

7 8 9

The hysteresis loop of the tensile tested specimen at room temperature (a) and tensile tested at high temperature (b)

The magnetic phase can be created under the high temperature andpressure conditions which is correspond to the stress corrosion crackingin the SG tube in the NPP(Bruemmer SM Charlot LA amp Henager CH (1988) Corrosion 782)

Principle of ECT

If we can separate magnetic phase selectively from the

flaws using magnetic sensor the reliability of EC in SGT

inspection will be greatly enhanced

Structure of the permeability

sensor

Dimension and photograph of U-shape

sensing yoke

Design of Magnetic Sensor for PVC

sensor sensing yoke

Photograph of the completed sensor front side (above) and rear side (bottom)

R11R12

R10

R8

R6

R9

R13

R7

R14

C18

1 n

C17

C20

C21

D2

DIODE

SIN COS

-

+

U-2A

4

13

2

-

+

U-2B

75

6

8

-

+

U-3A

13

2

8

+5VC19

104

+5V

Schematic diagram of the sensor system

Electronic Circuit of Magnetic Sensor

R20

R

R21

R

-

+

U5AD797

3

26

74

U6

D1

S12

GND3

+VCC4VCC5

IN6

-VCC7

S28

C41

R13

R26

R18

R25

R2210 Ω

R16

R14

R17

10 k

R15

R27

R32

R28

R33

R29

R34

5 k

R30

C29

C37

104

C32473

C39473C40

104

C33

104

C21

104C23

104

C25

104

C26

104

C30

104

C31

104

C35

104

C36

104

C27

104

C28

104

C34

104

C38

104

D3

DIODE

L1

1

2

L2

1

2

L3

1

2

4

-

+

U-4A

4

13

2

-

+

U-4B

75

6

8

-

+

U-5A

4

13

2

-

+

U-5B

75

6

8

-

+

U-6A

4

13

2

-

+

U-6B

75

6

8

C22

104

-5V

+5V

+5V

+5V

+5V

+5V

+5V

U7

D1

S12

GND3

+VCC4

VCC5

IN6

-VCC7

S28

+5V

-5V

-5V

-5V

-5V

-5V

-5V

-5V

-5V

R19

R24

R

R23

R

C24

OUT(X)

OUT(Y)

R1

20 kR210 k

R3

20 kR410 k

C1

104

C8

104

REF43

OUT(X)

OUT(Y)

REF43

U2

+Vcc1

CH02

CH13

CH24

CH35

COMM6

SHDN7

Vref8

+Vcc9

GND10

GND11

DOUT12BUSY13DIN14CS15

DIN16

-

+

U-1A

13

2

8

-

+

U-1B

4

75

6

C410 uF

C5104

DOUT

C210uF

C6104

C3104

DCLK

C7104

DIN

C10

01uF

CS

BUSY

C14 10uF

J1

CON6

123456

D1

DIODE

R5

47K

C9

10uF

C1310uF

Y1

OSC

OUT3

GND2

VCC4

U3

RSTVPP1

GND10

VCC20

XTAL15

XTAL24

P10AIN012P11AIN113P1214P1315P1416P1517P1618P1719

P30RXD2

P31TXD3

P32INT06

P33INT17

P34T08

P35T19

P3711

U4

C1+1

C1-3

C2+4

C2-5

VCC16

GND15

V+2

V-6

R1OUT12

R2OUT9

T1IN11

T2IN10

R1IN13

R2IN8

T1OUT14

T2OUT7

C12 10uF

C16

01uF

C15 10uF

C11

01uF

-5V

+5V

+5V

+5V

+5V

+5V

+5V

+5V

RST

OSC

OSC

RST

DCLKCSDINBUSYDOUT

U1

IN2

GND

4

OUT6

TEMP3

TRIM5

-5V

+5V

Electronic circuit diagram of the magnetic sensor

Photograph of the completed measuring system data acquisition

software in PC and probe scanning system

Experimental Setup for Magnetic Sensor

Reference material Scanning System Software LabVIEW

Reference Material (1) Normal defects and PVCs

Longitudinal and transverse defects

Def W L D Remarks

1 02 500 0213 (20 ) Inner defects

2 02 500 0427 (40 )

3 02 500 0213 (20 )Outer defectsPVC(1018)4 02 500 0427 (40 )

5 02 500 0639 (60 )

6 02 500 0852 (80 )

7 02 500 0639 (60 ) Inner defects

8 02 500 0852 (80 )

- 1 and 2 are inner defects

- 345 and 6 are outer defects with PVC

- 7 and 8 are inner defects

PVC

PVC

Defect Defect

For longitudinal defects and PVC For circumferential defects and PVC

ECT is very difficult to detect circumferential defects

We can distinguish PVCs and defects and longitudinal and circumferential defects

Flux-gate Magnetometer

One core sensor Two core sensor

3-축 flux-gate Magnetometer의 계략도

Sensorpia Co

pro

cess

or(

AV

R)

Sensor 1

RS422

Interface

Mic

ro-p

roce

ssor(

AV

R)

Sensor 2

Sensor 3

Interface

조립된 마그네토미터의 사진

Sensorpia Co

Analog PCB

Digital PCB

Sensorpia Co선형도(linearity)

10

20

30

40

50

60

y-axis

Magnetometer Output (microT)

-60 -50 -40 -30 -20 -10 0 10 20 30 40 50 60

-60

-50

-40

-30

-20

-10

0

10

Y-axis y=099946 x+0015STD 106E-4

Magnetometer Output (

Applied Magnetic Field (microT)

마그네토미터의 noise 특성 Sensorpia Co

1

10

100

y-axis

Magnetometer noise (nT)

0 1 2 3 4 5 6

1E-4

1E-3

001

01

Magnetometer noise (nT)

Frequency (Hz)

Magnetometer for KoDSAT

-150 -100 -50 0 50 100 150

-15

-10

-5

0

5

10

15

Magnetic Moment (Am

2)

Current (mA)

After Thermal Cycle Test

Measured

Resistance 193 ohm

Photograph of Magnetic torquer

Photograph of KoDSAT

Photograph of

3-axis Fluxgate

Magnetometer

Photograph of Magnetic torquer

Application of magnetometer

Moon magnetic fieldmeasurement

Telescope with direction indication

Joule Effect (Magnetostriction)

ϕ2cosel

l=

∆

0=∆

+∆

+∆

b

b

a

a

l

l

Actuator using Terfenol-D

00

05

10

B (T)

800

1000

1200

1400

1600

Magnetostriction (ppm)

-100 -50 0 50 100

-10

-05

00

B (T)

H (kAm)

2 MPa

4 MPa

6 MPa

8 MPa

10 MPa

12 MPa

-100 -50 0 50 100

-200

0

200

400

600

Magnetostriction (ppm)

H (kAm)

2 MPa

4 MPa

6 MPa

8 MPa

10 MPa

12 MPa

600

700

800

900

1000

-4 -3 -2 -1 0 1 2 3 4

0

10

20

30

40

50

60

Displacement (m

icro meter)

I (A)

FIELD

9 kAm

12 kAm

16 kAm

20 kAm

24 kAm

38 kAm

-50 -40 -30 -20 -10 0 10 20 30 40 50

-100

0

100

200

300

400

500

L (PPM)

H (kAm)

9 kAm

12 kAm

16 kAm

20 kAm

24 kAm

38 kAm

Magnetostrictive displacement sensor

Hysteresis loops under

tensile stress σ

(a) Crystalline 68 NiFe

λs = +25 10-6

(b) crystalline pure Ni λs

= -35 10-6

Villari Effect ( Inverse of Joule Effect)

= -35 10-6

(c) amorphous Co-based

alloy

λs = -35 10-6

ϕσλ 2sin2

3sdotsdot= smeE

γ

Permeability depending on the stress

σλmicromicro

1

3

2

Y

J

so

s

r =

γ

Calculated magnetization curves under stress

Variation of magnetization curve by an applied

tensile force (Co-based amorphous alloy)

Alloy Requirement

Materials for magnetoelastic sensors

Why amorphous magnetic materials are important

Stress-strain curves of several materials

Coercivity and hardness of several materials

Principles of magnetoelastic sensors

Non-contact torque sensor

Principle of cross torductor torque

sensor and flux pattern of sensor

poles on the surface of a shaft

a) without and b)with torsional load

Equivalent magnetic circuit of

cross type torque sensor

Helices of principal tensile and compressive stress on the surface of

a shaft subjected to torsion [32] Correlated changes of permeability

are detected by four-branch yoke system with sensing coils 123

and 4 and a common excitation pole

Examples of torque sensors

Four-branch type torque sensor

heads Pole structures realized

by commercial multi-pole

ferrites 14 and 18 min in

diameter (diameter of sensor

h e a d 1 7 a n d 2 4 m m

respectively) respectively)

Principle of Ring Torductor torque transducer

(a b) Physical structure (c) evolution of the

shaft surface under the transducer poles A and BRing torductor for measuring

torque on ship propeller shafts

(shaft diameter ca 500 mm)

(Courtesy ASEA Brown

Boveri AG)

Principal designs of coaxial torque sensors

Schematic diagram of data processing

electronics of a torque sensor

Extensometer (a) Construction of strain sensing element using

amorphous ribbon wound core (b) configuration of lumped

windings

∆E effect of an amorphous FeNi-based

alloy (Fe40 Ni38 Mo4 B18) Hs saturation

field

Magnetically tunable delay line

Torque Sensors using Amorphous wire

Sixtus tonk효과(large Barkhausen효과)

Hysteresis loops of a Wiegand wire for different reset fields

Curie 온도 및Hopkinson효과

Relation between normalised

saturation polarisation and

normalised Curie temperature

Permeability of a Mn-Zn ferrite as

a function of temperature and field

strength

Conclusions

1) Magnetic sensor 는 자동차 공장자동화 항공우주 및 군사용으로많이 사용되고 있다

2) 새로운 소재개발은 자기센서의 성능개발에 직접적인 영향을 준다2) 새로운 소재개발은 자기센서의 성능개발에 직접적인 영향을 준다

3) 센서의 개발을 위해서는 다양한 전공지식이 요구된다

(물리학 재료공학 기계공학 전자공학)

4) 센서분야가 고부가가치를 창출하는 부품사업이다

5) 핵심부품을 생산하는 중소기업의 item으로도 적절하다

-004

-002

000

002

004

006

M (emug)

Inconel 600 tested at RT

under tensile stress

1 2 3

4 5 6

7 8 9-004

-002

000

002

004

006

M(emug)

Inconel 600 Heat treated at

602 oC under tensile stress

1 2 3

How can we detect magnetic phase

(PVC)selectively from the flaws in SGT

-3000 -2000 -1000 0 1000 2000 3000

-006

H (Oe)

7 8 9

10 11 12

-3000 -2000 -1000 0 1000 2000 3000

-006

-004

H(Oe)

4 5 6

7 8 9

The hysteresis loop of the tensile tested specimen at room temperature (a) and tensile tested at high temperature (b)

The magnetic phase can be created under the high temperature andpressure conditions which is correspond to the stress corrosion crackingin the SG tube in the NPP(Bruemmer SM Charlot LA amp Henager CH (1988) Corrosion 782)

Principle of ECT

If we can separate magnetic phase selectively from the

flaws using magnetic sensor the reliability of EC in SGT

inspection will be greatly enhanced

Structure of the permeability

sensor

Dimension and photograph of U-shape

sensing yoke

Design of Magnetic Sensor for PVC

sensor sensing yoke

Photograph of the completed sensor front side (above) and rear side (bottom)

R11R12

R10

R8

R6

R9

R13

R7

R14

C18

1 n

C17

C20

C21

D2

DIODE

SIN COS

-

+

U-2A

4

13

2

-

+

U-2B

75

6

8

-

+

U-3A

13

2

8

+5VC19

104

+5V

Schematic diagram of the sensor system

Electronic Circuit of Magnetic Sensor

R20

R

R21

R

-

+

U5AD797

3

26

74

U6

D1

S12

GND3

+VCC4VCC5

IN6

-VCC7

S28

C41

R13

R26

R18

R25

R2210 Ω

R16

R14

R17

10 k

R15

R27

R32

R28

R33

R29

R34

5 k

R30

C29

C37

104

C32473

C39473C40

104

C33

104

C21

104C23

104

C25

104

C26

104

C30

104

C31

104

C35

104

C36

104

C27

104

C28

104

C34

104

C38

104

D3

DIODE

L1

1

2

L2

1

2

L3

1

2

4

-

+

U-4A

4

13

2

-

+

U-4B

75

6

8

-

+

U-5A

4

13

2

-

+

U-5B

75

6

8

-

+

U-6A

4

13

2

-

+

U-6B

75

6

8

C22

104

-5V

+5V

+5V

+5V

+5V

+5V

+5V

U7

D1

S12

GND3

+VCC4

VCC5

IN6

-VCC7

S28

+5V

-5V

-5V

-5V

-5V

-5V

-5V

-5V

-5V

R19

R24

R

R23

R

C24

OUT(X)

OUT(Y)

R1

20 kR210 k

R3

20 kR410 k

C1

104

C8

104

REF43

OUT(X)

OUT(Y)

REF43

U2

+Vcc1

CH02

CH13

CH24

CH35

COMM6

SHDN7

Vref8

+Vcc9

GND10

GND11

DOUT12BUSY13DIN14CS15

DIN16

-

+

U-1A

13

2

8

-

+

U-1B

4

75

6

C410 uF

C5104

DOUT

C210uF

C6104

C3104

DCLK

C7104

DIN

C10

01uF

CS

BUSY

C14 10uF

J1

CON6

123456

D1

DIODE

R5

47K

C9

10uF

C1310uF

Y1

OSC

OUT3

GND2

VCC4

U3

RSTVPP1

GND10

VCC20

XTAL15

XTAL24

P10AIN012P11AIN113P1214P1315P1416P1517P1618P1719

P30RXD2

P31TXD3

P32INT06

P33INT17

P34T08

P35T19

P3711

U4

C1+1

C1-3

C2+4

C2-5

VCC16

GND15

V+2

V-6

R1OUT12

R2OUT9

T1IN11

T2IN10

R1IN13

R2IN8

T1OUT14

T2OUT7

C12 10uF

C16

01uF

C15 10uF

C11

01uF

-5V

+5V

+5V

+5V

+5V

+5V

+5V

+5V

RST

OSC

OSC

RST

DCLKCSDINBUSYDOUT

U1

IN2

GND

4

OUT6

TEMP3

TRIM5

-5V

+5V

Electronic circuit diagram of the magnetic sensor

Photograph of the completed measuring system data acquisition

software in PC and probe scanning system

Experimental Setup for Magnetic Sensor

Reference material Scanning System Software LabVIEW

Reference Material (1) Normal defects and PVCs

Longitudinal and transverse defects

Def W L D Remarks

1 02 500 0213 (20 ) Inner defects

2 02 500 0427 (40 )

3 02 500 0213 (20 )Outer defectsPVC(1018)4 02 500 0427 (40 )

5 02 500 0639 (60 )

6 02 500 0852 (80 )

7 02 500 0639 (60 ) Inner defects

8 02 500 0852 (80 )

- 1 and 2 are inner defects

- 345 and 6 are outer defects with PVC

- 7 and 8 are inner defects

PVC

PVC

Defect Defect

For longitudinal defects and PVC For circumferential defects and PVC

ECT is very difficult to detect circumferential defects

We can distinguish PVCs and defects and longitudinal and circumferential defects

Flux-gate Magnetometer

One core sensor Two core sensor

3-축 flux-gate Magnetometer의 계략도

Sensorpia Co

pro

cess

or(

AV

R)

Sensor 1

RS422

Interface

Mic

ro-p

roce

ssor(

AV

R)

Sensor 2

Sensor 3

Interface

조립된 마그네토미터의 사진

Sensorpia Co

Analog PCB

Digital PCB

Sensorpia Co선형도(linearity)

10

20

30

40

50

60

y-axis

Magnetometer Output (microT)

-60 -50 -40 -30 -20 -10 0 10 20 30 40 50 60

-60

-50

-40

-30

-20

-10

0

10

Y-axis y=099946 x+0015STD 106E-4

Magnetometer Output (

Applied Magnetic Field (microT)

마그네토미터의 noise 특성 Sensorpia Co

1

10

100

y-axis

Magnetometer noise (nT)

0 1 2 3 4 5 6

1E-4

1E-3

001

01

Magnetometer noise (nT)

Frequency (Hz)

Magnetometer for KoDSAT

-150 -100 -50 0 50 100 150

-15

-10

-5

0

5

10

15

Magnetic Moment (Am

2)

Current (mA)

After Thermal Cycle Test

Measured

Resistance 193 ohm

Photograph of Magnetic torquer

Photograph of KoDSAT

Photograph of

3-axis Fluxgate

Magnetometer

Photograph of Magnetic torquer

Application of magnetometer

Moon magnetic fieldmeasurement

Telescope with direction indication

Joule Effect (Magnetostriction)

ϕ2cosel

l=

∆

0=∆

+∆

+∆

b

b

a

a

l

l

Actuator using Terfenol-D

00

05

10

B (T)

800

1000

1200

1400

1600

Magnetostriction (ppm)

-100 -50 0 50 100

-10

-05

00

B (T)

H (kAm)

2 MPa

4 MPa

6 MPa

8 MPa

10 MPa

12 MPa

-100 -50 0 50 100

-200

0

200

400

600

Magnetostriction (ppm)

H (kAm)

2 MPa

4 MPa

6 MPa

8 MPa

10 MPa

12 MPa

600

700

800

900

1000

-4 -3 -2 -1 0 1 2 3 4

0

10

20

30

40

50

60

Displacement (m

icro meter)

I (A)

FIELD

9 kAm

12 kAm

16 kAm

20 kAm

24 kAm

38 kAm

-50 -40 -30 -20 -10 0 10 20 30 40 50

-100

0

100

200

300

400

500

L (PPM)

H (kAm)

9 kAm

12 kAm

16 kAm

20 kAm

24 kAm

38 kAm

Magnetostrictive displacement sensor

Hysteresis loops under

tensile stress σ

(a) Crystalline 68 NiFe

λs = +25 10-6

(b) crystalline pure Ni λs

= -35 10-6

Villari Effect ( Inverse of Joule Effect)

= -35 10-6

(c) amorphous Co-based

alloy

λs = -35 10-6

ϕσλ 2sin2

3sdotsdot= smeE

γ

Permeability depending on the stress

σλmicromicro

1

3

2

Y

J

so

s

r =

γ

Calculated magnetization curves under stress

Variation of magnetization curve by an applied

tensile force (Co-based amorphous alloy)

Alloy Requirement

Materials for magnetoelastic sensors

Why amorphous magnetic materials are important

Stress-strain curves of several materials

Coercivity and hardness of several materials

Principles of magnetoelastic sensors

Non-contact torque sensor

Principle of cross torductor torque

sensor and flux pattern of sensor

poles on the surface of a shaft

a) without and b)with torsional load

Equivalent magnetic circuit of

cross type torque sensor

Helices of principal tensile and compressive stress on the surface of

a shaft subjected to torsion [32] Correlated changes of permeability

are detected by four-branch yoke system with sensing coils 123

and 4 and a common excitation pole

Examples of torque sensors

Four-branch type torque sensor

heads Pole structures realized

by commercial multi-pole

ferrites 14 and 18 min in

diameter (diameter of sensor

h e a d 1 7 a n d 2 4 m m

respectively) respectively)

Principle of Ring Torductor torque transducer

(a b) Physical structure (c) evolution of the

shaft surface under the transducer poles A and BRing torductor for measuring

torque on ship propeller shafts

(shaft diameter ca 500 mm)

(Courtesy ASEA Brown

Boveri AG)

Principal designs of coaxial torque sensors

Schematic diagram of data processing

electronics of a torque sensor

Extensometer (a) Construction of strain sensing element using

amorphous ribbon wound core (b) configuration of lumped

windings

∆E effect of an amorphous FeNi-based

alloy (Fe40 Ni38 Mo4 B18) Hs saturation

field

Magnetically tunable delay line

Torque Sensors using Amorphous wire

Sixtus tonk효과(large Barkhausen효과)

Hysteresis loops of a Wiegand wire for different reset fields

Curie 온도 및Hopkinson효과

Relation between normalised

saturation polarisation and

normalised Curie temperature

Permeability of a Mn-Zn ferrite as

a function of temperature and field

strength

Conclusions

1) Magnetic sensor 는 자동차 공장자동화 항공우주 및 군사용으로많이 사용되고 있다

2) 새로운 소재개발은 자기센서의 성능개발에 직접적인 영향을 준다2) 새로운 소재개발은 자기센서의 성능개발에 직접적인 영향을 준다

3) 센서의 개발을 위해서는 다양한 전공지식이 요구된다

(물리학 재료공학 기계공학 전자공학)

4) 센서분야가 고부가가치를 창출하는 부품사업이다

5) 핵심부품을 생산하는 중소기업의 item으로도 적절하다

Principle of ECT

If we can separate magnetic phase selectively from the

flaws using magnetic sensor the reliability of EC in SGT

inspection will be greatly enhanced

Structure of the permeability

sensor

Dimension and photograph of U-shape

sensing yoke

Design of Magnetic Sensor for PVC

sensor sensing yoke

Photograph of the completed sensor front side (above) and rear side (bottom)

R11R12

R10

R8

R6

R9

R13

R7

R14

C18

1 n

C17

C20

C21

D2

DIODE

SIN COS

-

+

U-2A

4

13

2

-

+

U-2B

75

6

8

-

+

U-3A

13

2

8

+5VC19

104

+5V

Schematic diagram of the sensor system

Electronic Circuit of Magnetic Sensor

R20

R

R21

R

-

+

U5AD797

3

26

74

U6

D1

S12

GND3

+VCC4VCC5

IN6

-VCC7

S28

C41

R13

R26

R18

R25

R2210 Ω

R16

R14

R17

10 k

R15

R27

R32

R28

R33

R29

R34

5 k

R30

C29

C37

104

C32473

C39473C40

104

C33

104

C21

104C23

104

C25

104

C26

104

C30

104

C31

104

C35

104

C36

104

C27

104

C28

104

C34

104

C38

104

D3

DIODE

L1

1

2

L2

1

2

L3

1

2

4

-

+

U-4A

4

13

2

-

+

U-4B

75

6

8

-

+

U-5A

4

13

2

-

+

U-5B

75

6

8

-

+

U-6A

4

13

2

-

+

U-6B

75

6

8

C22

104

-5V

+5V

+5V

+5V

+5V

+5V

+5V

U7

D1

S12

GND3

+VCC4

VCC5

IN6

-VCC7

S28

+5V

-5V

-5V

-5V

-5V

-5V

-5V

-5V

-5V

R19

R24

R

R23

R

C24

OUT(X)

OUT(Y)

R1

20 kR210 k

R3

20 kR410 k

C1

104

C8

104

REF43

OUT(X)

OUT(Y)

REF43

U2

+Vcc1

CH02

CH13

CH24

CH35

COMM6

SHDN7

Vref8

+Vcc9

GND10

GND11

DOUT12BUSY13DIN14CS15

DIN16

-

+

U-1A

13

2

8

-

+

U-1B

4

75

6

C410 uF

C5104

DOUT

C210uF

C6104

C3104

DCLK

C7104

DIN

C10

01uF

CS

BUSY

C14 10uF

J1

CON6

123456

D1

DIODE

R5

47K

C9

10uF

C1310uF

Y1

OSC

OUT3

GND2

VCC4

U3

RSTVPP1

GND10

VCC20

XTAL15

XTAL24

P10AIN012P11AIN113P1214P1315P1416P1517P1618P1719

P30RXD2

P31TXD3

P32INT06

P33INT17

P34T08

P35T19

P3711

U4

C1+1

C1-3

C2+4

C2-5

VCC16

GND15

V+2

V-6

R1OUT12

R2OUT9

T1IN11

T2IN10

R1IN13

R2IN8

T1OUT14

T2OUT7

C12 10uF

C16

01uF

C15 10uF

C11

01uF

-5V

+5V

+5V

+5V

+5V

+5V

+5V

+5V

RST

OSC

OSC

RST

DCLKCSDINBUSYDOUT

U1

IN2

GND

4

OUT6

TEMP3

TRIM5

-5V

+5V

Electronic circuit diagram of the magnetic sensor

Photograph of the completed measuring system data acquisition

software in PC and probe scanning system

Experimental Setup for Magnetic Sensor

Reference material Scanning System Software LabVIEW

Reference Material (1) Normal defects and PVCs

Longitudinal and transverse defects

Def W L D Remarks

1 02 500 0213 (20 ) Inner defects

2 02 500 0427 (40 )

3 02 500 0213 (20 )Outer defectsPVC(1018)4 02 500 0427 (40 )

5 02 500 0639 (60 )

6 02 500 0852 (80 )

7 02 500 0639 (60 ) Inner defects

8 02 500 0852 (80 )

- 1 and 2 are inner defects

- 345 and 6 are outer defects with PVC

- 7 and 8 are inner defects

PVC

PVC

Defect Defect

For longitudinal defects and PVC For circumferential defects and PVC

ECT is very difficult to detect circumferential defects

We can distinguish PVCs and defects and longitudinal and circumferential defects

Flux-gate Magnetometer

One core sensor Two core sensor

3-축 flux-gate Magnetometer의 계략도

Sensorpia Co

pro

cess

or(

AV

R)

Sensor 1

RS422

Interface

Mic

ro-p

roce

ssor(

AV

R)

Sensor 2

Sensor 3

Interface

조립된 마그네토미터의 사진

Sensorpia Co

Analog PCB

Digital PCB

Sensorpia Co선형도(linearity)

10

20

30

40

50

60

y-axis

Magnetometer Output (microT)

-60 -50 -40 -30 -20 -10 0 10 20 30 40 50 60

-60

-50

-40

-30

-20

-10

0

10

Y-axis y=099946 x+0015STD 106E-4

Magnetometer Output (

Applied Magnetic Field (microT)

마그네토미터의 noise 특성 Sensorpia Co

1

10

100

y-axis

Magnetometer noise (nT)

0 1 2 3 4 5 6

1E-4

1E-3

001

01

Magnetometer noise (nT)

Frequency (Hz)

Magnetometer for KoDSAT

-150 -100 -50 0 50 100 150

-15

-10

-5

0

5

10

15

Magnetic Moment (Am

2)

Current (mA)

After Thermal Cycle Test

Measured

Resistance 193 ohm

Photograph of Magnetic torquer

Photograph of KoDSAT

Photograph of

3-axis Fluxgate

Magnetometer

Photograph of Magnetic torquer

Application of magnetometer

Moon magnetic fieldmeasurement

Telescope with direction indication

Joule Effect (Magnetostriction)

ϕ2cosel

l=

∆

0=∆

+∆

+∆

b

b

a

a

l

l

Actuator using Terfenol-D

00

05

10

B (T)

800

1000

1200

1400

1600

Magnetostriction (ppm)

-100 -50 0 50 100

-10

-05

00

B (T)

H (kAm)

2 MPa

4 MPa

6 MPa

8 MPa

10 MPa

12 MPa

-100 -50 0 50 100

-200

0

200

400

600

Magnetostriction (ppm)

H (kAm)

2 MPa

4 MPa

6 MPa

8 MPa

10 MPa

12 MPa

600

700

800

900

1000

-4 -3 -2 -1 0 1 2 3 4

0

10

20

30

40

50

60

Displacement (m

icro meter)

I (A)

FIELD

9 kAm

12 kAm

16 kAm

20 kAm

24 kAm

38 kAm

-50 -40 -30 -20 -10 0 10 20 30 40 50

-100

0

100

200

300

400

500

L (PPM)

H (kAm)

9 kAm

12 kAm

16 kAm

20 kAm

24 kAm

38 kAm

Magnetostrictive displacement sensor

Hysteresis loops under

tensile stress σ

(a) Crystalline 68 NiFe

λs = +25 10-6

(b) crystalline pure Ni λs

= -35 10-6

Villari Effect ( Inverse of Joule Effect)

= -35 10-6

(c) amorphous Co-based

alloy

λs = -35 10-6

ϕσλ 2sin2

3sdotsdot= smeE

γ

Permeability depending on the stress

σλmicromicro

1

3

2

Y

J

so

s

r =

γ

Calculated magnetization curves under stress

Variation of magnetization curve by an applied

tensile force (Co-based amorphous alloy)

Alloy Requirement

Materials for magnetoelastic sensors

Why amorphous magnetic materials are important

Stress-strain curves of several materials

Coercivity and hardness of several materials

Principles of magnetoelastic sensors

Non-contact torque sensor

Principle of cross torductor torque

sensor and flux pattern of sensor

poles on the surface of a shaft

a) without and b)with torsional load

Equivalent magnetic circuit of

cross type torque sensor

Helices of principal tensile and compressive stress on the surface of

a shaft subjected to torsion [32] Correlated changes of permeability

are detected by four-branch yoke system with sensing coils 123

and 4 and a common excitation pole

Examples of torque sensors

Four-branch type torque sensor

heads Pole structures realized

by commercial multi-pole

ferrites 14 and 18 min in

diameter (diameter of sensor

h e a d 1 7 a n d 2 4 m m

respectively) respectively)

Principle of Ring Torductor torque transducer

(a b) Physical structure (c) evolution of the

shaft surface under the transducer poles A and BRing torductor for measuring

torque on ship propeller shafts

(shaft diameter ca 500 mm)

(Courtesy ASEA Brown

Boveri AG)

Principal designs of coaxial torque sensors

Schematic diagram of data processing

electronics of a torque sensor

Extensometer (a) Construction of strain sensing element using

amorphous ribbon wound core (b) configuration of lumped

windings

∆E effect of an amorphous FeNi-based

alloy (Fe40 Ni38 Mo4 B18) Hs saturation

field

Magnetically tunable delay line

Torque Sensors using Amorphous wire

Sixtus tonk효과(large Barkhausen효과)

Hysteresis loops of a Wiegand wire for different reset fields

Curie 온도 및Hopkinson효과

Relation between normalised

saturation polarisation and

normalised Curie temperature

Permeability of a Mn-Zn ferrite as

a function of temperature and field

strength

Conclusions

1) Magnetic sensor 는 자동차 공장자동화 항공우주 및 군사용으로많이 사용되고 있다

2) 새로운 소재개발은 자기센서의 성능개발에 직접적인 영향을 준다2) 새로운 소재개발은 자기센서의 성능개발에 직접적인 영향을 준다

3) 센서의 개발을 위해서는 다양한 전공지식이 요구된다

(물리학 재료공학 기계공학 전자공학)

4) 센서분야가 고부가가치를 창출하는 부품사업이다

5) 핵심부품을 생산하는 중소기업의 item으로도 적절하다

Structure of the permeability

sensor

Dimension and photograph of U-shape

sensing yoke

Design of Magnetic Sensor for PVC

sensor sensing yoke

Photograph of the completed sensor front side (above) and rear side (bottom)

R11R12

R10

R8

R6

R9

R13

R7

R14

C18

1 n

C17

C20

C21

D2

DIODE

SIN COS

-

+

U-2A

4

13

2

-

+

U-2B

75

6

8

-

+

U-3A

13

2

8

+5VC19

104

+5V

Schematic diagram of the sensor system

Electronic Circuit of Magnetic Sensor

R20

R

R21

R

-

+

U5AD797

3

26

74

U6

D1

S12

GND3

+VCC4VCC5

IN6

-VCC7

S28

C41

R13

R26

R18

R25

R2210 Ω

R16

R14

R17

10 k

R15

R27

R32

R28

R33

R29

R34

5 k

R30

C29

C37

104

C32473

C39473C40

104

C33

104

C21

104C23

104

C25

104

C26

104

C30

104

C31

104

C35

104

C36

104

C27

104

C28

104

C34

104

C38

104

D3

DIODE

L1

1

2

L2

1

2

L3

1

2

4

-

+

U-4A

4

13

2

-

+

U-4B

75

6

8

-

+

U-5A

4

13

2

-

+

U-5B

75

6

8

-

+

U-6A

4

13

2

-

+

U-6B

75

6

8

C22

104

-5V

+5V

+5V

+5V

+5V

+5V

+5V

U7

D1

S12

GND3

+VCC4

VCC5

IN6

-VCC7

S28

+5V

-5V

-5V

-5V

-5V

-5V

-5V

-5V

-5V

R19

R24

R

R23

R

C24

OUT(X)

OUT(Y)

R1

20 kR210 k

R3

20 kR410 k

C1

104

C8

104

REF43

OUT(X)

OUT(Y)

REF43

U2

+Vcc1

CH02

CH13

CH24

CH35

COMM6

SHDN7

Vref8

+Vcc9

GND10

GND11

DOUT12BUSY13DIN14CS15

DIN16

-

+

U-1A

13

2

8

-

+

U-1B

4

75

6

C410 uF

C5104

DOUT

C210uF

C6104

C3104

DCLK

C7104

DIN

C10

01uF

CS

BUSY

C14 10uF

J1

CON6

123456

D1

DIODE

R5

47K

C9

10uF

C1310uF

Y1

OSC

OUT3

GND2

VCC4

U3

RSTVPP1

GND10

VCC20

XTAL15

XTAL24

P10AIN012P11AIN113P1214P1315P1416P1517P1618P1719

P30RXD2

P31TXD3

P32INT06

P33INT17

P34T08

P35T19

P3711

U4

C1+1

C1-3

C2+4

C2-5

VCC16

GND15

V+2

V-6

R1OUT12

R2OUT9

T1IN11

T2IN10

R1IN13

R2IN8

T1OUT14

T2OUT7

C12 10uF

C16

01uF

C15 10uF

C11

01uF

-5V

+5V

+5V

+5V

+5V

+5V

+5V

+5V

RST

OSC

OSC

RST

DCLKCSDINBUSYDOUT

U1

IN2

GND

4

OUT6

TEMP3

TRIM5

-5V

+5V

Electronic circuit diagram of the magnetic sensor

Photograph of the completed measuring system data acquisition

software in PC and probe scanning system

Experimental Setup for Magnetic Sensor

Reference material Scanning System Software LabVIEW

Reference Material (1) Normal defects and PVCs

Longitudinal and transverse defects

Def W L D Remarks

1 02 500 0213 (20 ) Inner defects

2 02 500 0427 (40 )

3 02 500 0213 (20 )Outer defectsPVC(1018)4 02 500 0427 (40 )

5 02 500 0639 (60 )

6 02 500 0852 (80 )

7 02 500 0639 (60 ) Inner defects

8 02 500 0852 (80 )

- 1 and 2 are inner defects

- 345 and 6 are outer defects with PVC

- 7 and 8 are inner defects

PVC

PVC

Defect Defect

For longitudinal defects and PVC For circumferential defects and PVC

ECT is very difficult to detect circumferential defects

We can distinguish PVCs and defects and longitudinal and circumferential defects

Flux-gate Magnetometer

One core sensor Two core sensor

3-축 flux-gate Magnetometer의 계략도

Sensorpia Co

pro

cess

or(

AV

R)

Sensor 1

RS422

Interface

Mic

ro-p

roce

ssor(

AV

R)

Sensor 2

Sensor 3

Interface

조립된 마그네토미터의 사진

Sensorpia Co

Analog PCB

Digital PCB

Sensorpia Co선형도(linearity)

10

20

30

40

50

60

y-axis

Magnetometer Output (microT)

-60 -50 -40 -30 -20 -10 0 10 20 30 40 50 60

-60

-50

-40

-30

-20

-10

0

10

Y-axis y=099946 x+0015STD 106E-4

Magnetometer Output (

Applied Magnetic Field (microT)

마그네토미터의 noise 특성 Sensorpia Co

1

10

100

y-axis

Magnetometer noise (nT)

0 1 2 3 4 5 6

1E-4

1E-3

001

01

Magnetometer noise (nT)

Frequency (Hz)

Magnetometer for KoDSAT

-150 -100 -50 0 50 100 150

-15

-10

-5

0

5

10

15

Magnetic Moment (Am

2)

Current (mA)

After Thermal Cycle Test

Measured

Resistance 193 ohm

Photograph of Magnetic torquer

Photograph of KoDSAT

Photograph of

3-axis Fluxgate

Magnetometer

Photograph of Magnetic torquer

Application of magnetometer

Moon magnetic fieldmeasurement

Telescope with direction indication

Joule Effect (Magnetostriction)

ϕ2cosel

l=

∆

0=∆

+∆

+∆

b

b

a

a

l

l

Actuator using Terfenol-D

00

05

10

B (T)

800

1000

1200

1400

1600

Magnetostriction (ppm)

-100 -50 0 50 100

-10

-05

00

B (T)

H (kAm)

2 MPa

4 MPa

6 MPa

8 MPa

10 MPa

12 MPa

-100 -50 0 50 100

-200

0

200

400

600

Magnetostriction (ppm)

H (kAm)

2 MPa

4 MPa

6 MPa

8 MPa

10 MPa

12 MPa

600

700

800

900

1000

-4 -3 -2 -1 0 1 2 3 4

0

10

20

30

40

50

60

Displacement (m

icro meter)

I (A)

FIELD

9 kAm

12 kAm

16 kAm

20 kAm

24 kAm

38 kAm

-50 -40 -30 -20 -10 0 10 20 30 40 50

-100

0

100

200

300

400

500

L (PPM)

H (kAm)

9 kAm

12 kAm

16 kAm

20 kAm

24 kAm

38 kAm

Magnetostrictive displacement sensor

Hysteresis loops under

tensile stress σ

(a) Crystalline 68 NiFe

λs = +25 10-6

(b) crystalline pure Ni λs

= -35 10-6

Villari Effect ( Inverse of Joule Effect)

= -35 10-6

(c) amorphous Co-based

alloy

λs = -35 10-6

ϕσλ 2sin2

3sdotsdot= smeE

γ

Permeability depending on the stress

σλmicromicro

1

3

2

Y

J

so

s

r =

γ

Calculated magnetization curves under stress

Variation of magnetization curve by an applied

tensile force (Co-based amorphous alloy)

Alloy Requirement

Materials for magnetoelastic sensors

Why amorphous magnetic materials are important

Stress-strain curves of several materials

Coercivity and hardness of several materials

Principles of magnetoelastic sensors

Non-contact torque sensor

Principle of cross torductor torque

sensor and flux pattern of sensor

poles on the surface of a shaft

a) without and b)with torsional load

Equivalent magnetic circuit of

cross type torque sensor

Helices of principal tensile and compressive stress on the surface of

a shaft subjected to torsion [32] Correlated changes of permeability

are detected by four-branch yoke system with sensing coils 123

and 4 and a common excitation pole

Examples of torque sensors

Four-branch type torque sensor

heads Pole structures realized

by commercial multi-pole

ferrites 14 and 18 min in

diameter (diameter of sensor

h e a d 1 7 a n d 2 4 m m

respectively) respectively)

Principle of Ring Torductor torque transducer

(a b) Physical structure (c) evolution of the

shaft surface under the transducer poles A and BRing torductor for measuring

torque on ship propeller shafts

(shaft diameter ca 500 mm)

(Courtesy ASEA Brown

Boveri AG)

Principal designs of coaxial torque sensors

Schematic diagram of data processing

electronics of a torque sensor

Extensometer (a) Construction of strain sensing element using

amorphous ribbon wound core (b) configuration of lumped

windings

∆E effect of an amorphous FeNi-based

alloy (Fe40 Ni38 Mo4 B18) Hs saturation

field

Magnetically tunable delay line

Torque Sensors using Amorphous wire

Sixtus tonk효과(large Barkhausen효과)

Hysteresis loops of a Wiegand wire for different reset fields

Curie 온도 및Hopkinson효과

Relation between normalised

saturation polarisation and

normalised Curie temperature

Permeability of a Mn-Zn ferrite as

a function of temperature and field

strength

Conclusions

1) Magnetic sensor 는 자동차 공장자동화 항공우주 및 군사용으로많이 사용되고 있다

2) 새로운 소재개발은 자기센서의 성능개발에 직접적인 영향을 준다2) 새로운 소재개발은 자기센서의 성능개발에 직접적인 영향을 준다

3) 센서의 개발을 위해서는 다양한 전공지식이 요구된다

(물리학 재료공학 기계공학 전자공학)

4) 센서분야가 고부가가치를 창출하는 부품사업이다

5) 핵심부품을 생산하는 중소기업의 item으로도 적절하다

R11R12

R10

R8

R6

R9

R13

R7

R14

C18

1 n

C17

C20

C21

D2

DIODE

SIN COS

-

+

U-2A

4

13

2

-

+

U-2B

75

6

8

-

+

U-3A

13

2

8

+5VC19

104

+5V

Schematic diagram of the sensor system

Electronic Circuit of Magnetic Sensor

R20

R

R21

R

-

+

U5AD797

3

26

74

U6

D1

S12

GND3

+VCC4VCC5

IN6

-VCC7

S28

C41

R13

R26

R18

R25

R2210 Ω

R16

R14

R17

10 k

R15

R27

R32

R28

R33

R29

R34

5 k

R30

C29

C37

104

C32473

C39473C40

104

C33

104

C21

104C23

104

C25

104

C26

104

C30

104

C31

104

C35

104

C36

104

C27

104

C28

104

C34

104

C38

104

D3

DIODE

L1

1

2

L2

1

2

L3

1

2

4

-

+

U-4A

4

13

2

-

+

U-4B

75

6

8

-

+

U-5A

4

13

2

-

+

U-5B

75

6

8

-

+

U-6A

4

13

2

-

+

U-6B

75

6

8

C22

104

-5V

+5V

+5V

+5V

+5V

+5V

+5V

U7

D1

S12

GND3

+VCC4

VCC5

IN6

-VCC7

S28

+5V

-5V

-5V

-5V

-5V

-5V

-5V

-5V

-5V

R19

R24

R

R23

R

C24

OUT(X)

OUT(Y)

R1

20 kR210 k

R3

20 kR410 k

C1

104

C8

104

REF43

OUT(X)

OUT(Y)

REF43

U2

+Vcc1

CH02

CH13

CH24

CH35

COMM6

SHDN7

Vref8

+Vcc9

GND10

GND11

DOUT12BUSY13DIN14CS15

DIN16

-

+

U-1A

13

2

8

-

+

U-1B

4

75

6

C410 uF

C5104

DOUT

C210uF

C6104

C3104

DCLK

C7104

DIN

C10

01uF

CS

BUSY

C14 10uF

J1

CON6

123456

D1

DIODE

R5

47K

C9

10uF

C1310uF

Y1

OSC

OUT3

GND2

VCC4

U3

RSTVPP1

GND10

VCC20

XTAL15

XTAL24

P10AIN012P11AIN113P1214P1315P1416P1517P1618P1719

P30RXD2

P31TXD3

P32INT06

P33INT17

P34T08

P35T19

P3711

U4

C1+1

C1-3

C2+4

C2-5

VCC16

GND15

V+2

V-6

R1OUT12

R2OUT9

T1IN11

T2IN10

R1IN13

R2IN8

T1OUT14

T2OUT7

C12 10uF

C16

01uF

C15 10uF

C11

01uF

-5V

+5V

+5V

+5V

+5V

+5V

+5V

+5V

RST

OSC

OSC

RST

DCLKCSDINBUSYDOUT

U1

IN2

GND

4

OUT6

TEMP3

TRIM5

-5V

+5V

Electronic circuit diagram of the magnetic sensor

Photograph of the completed measuring system data acquisition

software in PC and probe scanning system

Experimental Setup for Magnetic Sensor

Reference material Scanning System Software LabVIEW

Reference Material (1) Normal defects and PVCs

Longitudinal and transverse defects

Def W L D Remarks

1 02 500 0213 (20 ) Inner defects

2 02 500 0427 (40 )

3 02 500 0213 (20 )Outer defectsPVC(1018)4 02 500 0427 (40 )

5 02 500 0639 (60 )

6 02 500 0852 (80 )

7 02 500 0639 (60 ) Inner defects

8 02 500 0852 (80 )

- 1 and 2 are inner defects

- 345 and 6 are outer defects with PVC

- 7 and 8 are inner defects

PVC

PVC

Defect Defect

For longitudinal defects and PVC For circumferential defects and PVC

ECT is very difficult to detect circumferential defects

We can distinguish PVCs and defects and longitudinal and circumferential defects

Flux-gate Magnetometer

One core sensor Two core sensor

3-축 flux-gate Magnetometer의 계략도

Sensorpia Co

pro

cess

or(

AV

R)

Sensor 1

RS422

Interface

Mic

ro-p

roce

ssor(

AV

R)

Sensor 2

Sensor 3

Interface

조립된 마그네토미터의 사진

Sensorpia Co

Analog PCB

Digital PCB

Sensorpia Co선형도(linearity)

10

20

30

40

50

60

y-axis

Magnetometer Output (microT)

-60 -50 -40 -30 -20 -10 0 10 20 30 40 50 60

-60

-50

-40

-30

-20

-10

0

10

Y-axis y=099946 x+0015STD 106E-4

Magnetometer Output (

Applied Magnetic Field (microT)

마그네토미터의 noise 특성 Sensorpia Co

1

10

100

y-axis

Magnetometer noise (nT)

0 1 2 3 4 5 6

1E-4

1E-3

001

01

Magnetometer noise (nT)

Frequency (Hz)

Magnetometer for KoDSAT

-150 -100 -50 0 50 100 150

-15

-10

-5

0

5

10

15

Magnetic Moment (Am

2)

Current (mA)

After Thermal Cycle Test

Measured

Resistance 193 ohm

Photograph of Magnetic torquer

Photograph of KoDSAT

Photograph of

3-axis Fluxgate

Magnetometer

Photograph of Magnetic torquer

Application of magnetometer

Moon magnetic fieldmeasurement

Telescope with direction indication

Joule Effect (Magnetostriction)

ϕ2cosel

l=

∆

0=∆

+∆

+∆

b

b

a

a

l

l

Actuator using Terfenol-D

00

05

10

B (T)

800

1000

1200

1400

1600

Magnetostriction (ppm)

-100 -50 0 50 100

-10

-05

00

B (T)

H (kAm)

2 MPa

4 MPa

6 MPa

8 MPa

10 MPa

12 MPa

-100 -50 0 50 100

-200

0

200

400

600

Magnetostriction (ppm)

H (kAm)

2 MPa

4 MPa

6 MPa

8 MPa

10 MPa

12 MPa

600

700

800

900

1000

-4 -3 -2 -1 0 1 2 3 4

0

10

20

30

40

50

60

Displacement (m

icro meter)

I (A)

FIELD

9 kAm

12 kAm

16 kAm

20 kAm

24 kAm

38 kAm

-50 -40 -30 -20 -10 0 10 20 30 40 50

-100

0

100

200

300

400

500

L (PPM)

H (kAm)

9 kAm

12 kAm

16 kAm

20 kAm

24 kAm

38 kAm

Magnetostrictive displacement sensor

Hysteresis loops under

tensile stress σ

(a) Crystalline 68 NiFe

λs = +25 10-6

(b) crystalline pure Ni λs

= -35 10-6

Villari Effect ( Inverse of Joule Effect)

= -35 10-6

(c) amorphous Co-based

alloy

λs = -35 10-6

ϕσλ 2sin2

3sdotsdot= smeE

γ

Permeability depending on the stress

σλmicromicro

1

3

2

Y

J

so

s

r =

γ

Calculated magnetization curves under stress

Variation of magnetization curve by an applied

tensile force (Co-based amorphous alloy)

Alloy Requirement

Materials for magnetoelastic sensors

Why amorphous magnetic materials are important

Stress-strain curves of several materials

Coercivity and hardness of several materials

Principles of magnetoelastic sensors

Non-contact torque sensor

Principle of cross torductor torque

sensor and flux pattern of sensor

poles on the surface of a shaft

a) without and b)with torsional load

Equivalent magnetic circuit of

cross type torque sensor

Helices of principal tensile and compressive stress on the surface of

a shaft subjected to torsion [32] Correlated changes of permeability

are detected by four-branch yoke system with sensing coils 123

and 4 and a common excitation pole

Examples of torque sensors

Four-branch type torque sensor

heads Pole structures realized

by commercial multi-pole

ferrites 14 and 18 min in

diameter (diameter of sensor

h e a d 1 7 a n d 2 4 m m

respectively) respectively)

Principle of Ring Torductor torque transducer

(a b) Physical structure (c) evolution of the

shaft surface under the transducer poles A and BRing torductor for measuring

torque on ship propeller shafts

(shaft diameter ca 500 mm)

(Courtesy ASEA Brown

Boveri AG)

Principal designs of coaxial torque sensors

Schematic diagram of data processing

electronics of a torque sensor

Extensometer (a) Construction of strain sensing element using

amorphous ribbon wound core (b) configuration of lumped

windings

∆E effect of an amorphous FeNi-based

alloy (Fe40 Ni38 Mo4 B18) Hs saturation

field

Magnetically tunable delay line

Torque Sensors using Amorphous wire

Sixtus tonk효과(large Barkhausen효과)

Hysteresis loops of a Wiegand wire for different reset fields

Curie 온도 및Hopkinson효과

Relation between normalised

saturation polarisation and

normalised Curie temperature

Permeability of a Mn-Zn ferrite as

a function of temperature and field

strength

Conclusions

1) Magnetic sensor 는 자동차 공장자동화 항공우주 및 군사용으로많이 사용되고 있다

2) 새로운 소재개발은 자기센서의 성능개발에 직접적인 영향을 준다2) 새로운 소재개발은 자기센서의 성능개발에 직접적인 영향을 준다

3) 센서의 개발을 위해서는 다양한 전공지식이 요구된다

(물리학 재료공학 기계공학 전자공학)

4) 센서분야가 고부가가치를 창출하는 부품사업이다

5) 핵심부품을 생산하는 중소기업의 item으로도 적절하다

Photograph of the completed measuring system data acquisition

software in PC and probe scanning system

Experimental Setup for Magnetic Sensor

Reference material Scanning System Software LabVIEW

Reference Material (1) Normal defects and PVCs

Longitudinal and transverse defects

Def W L D Remarks

1 02 500 0213 (20 ) Inner defects

2 02 500 0427 (40 )

3 02 500 0213 (20 )Outer defectsPVC(1018)4 02 500 0427 (40 )

5 02 500 0639 (60 )

6 02 500 0852 (80 )

7 02 500 0639 (60 ) Inner defects

8 02 500 0852 (80 )

- 1 and 2 are inner defects

- 345 and 6 are outer defects with PVC

- 7 and 8 are inner defects

PVC

PVC

Defect Defect

For longitudinal defects and PVC For circumferential defects and PVC

ECT is very difficult to detect circumferential defects

We can distinguish PVCs and defects and longitudinal and circumferential defects

Flux-gate Magnetometer

One core sensor Two core sensor

3-축 flux-gate Magnetometer의 계략도

Sensorpia Co

pro

cess

or(

AV

R)

Sensor 1

RS422

Interface

Mic

ro-p

roce

ssor(

AV

R)

Sensor 2

Sensor 3

Interface

조립된 마그네토미터의 사진

Sensorpia Co

Analog PCB

Digital PCB

Sensorpia Co선형도(linearity)

10

20

30

40

50

60

y-axis

Magnetometer Output (microT)

-60 -50 -40 -30 -20 -10 0 10 20 30 40 50 60

-60

-50

-40

-30

-20

-10

0

10

Y-axis y=099946 x+0015STD 106E-4

Magnetometer Output (

Applied Magnetic Field (microT)

마그네토미터의 noise 특성 Sensorpia Co

1

10

100

y-axis

Magnetometer noise (nT)

0 1 2 3 4 5 6

1E-4

1E-3

001

01

Magnetometer noise (nT)

Frequency (Hz)

Magnetometer for KoDSAT

-150 -100 -50 0 50 100 150

-15

-10

-5

0

5

10

15

Magnetic Moment (Am

2)

Current (mA)

After Thermal Cycle Test

Measured

Resistance 193 ohm

Photograph of Magnetic torquer

Photograph of KoDSAT

Photograph of

3-axis Fluxgate

Magnetometer

Photograph of Magnetic torquer

Application of magnetometer

Moon magnetic fieldmeasurement

Telescope with direction indication

Joule Effect (Magnetostriction)

ϕ2cosel

l=

∆

0=∆

+∆

+∆

b

b

a

a

l

l

Actuator using Terfenol-D

00

05

10

B (T)

800

1000

1200

1400

1600

Magnetostriction (ppm)

-100 -50 0 50 100

-10

-05

00

B (T)

H (kAm)

2 MPa

4 MPa

6 MPa

8 MPa

10 MPa

12 MPa

-100 -50 0 50 100

-200

0

200

400

600

Magnetostriction (ppm)

H (kAm)

2 MPa

4 MPa

6 MPa

8 MPa

10 MPa

12 MPa

600

700

800

900

1000

-4 -3 -2 -1 0 1 2 3 4

0

10

20

30

40

50

60

Displacement (m

icro meter)

I (A)

FIELD

9 kAm

12 kAm

16 kAm

20 kAm

24 kAm

38 kAm

-50 -40 -30 -20 -10 0 10 20 30 40 50

-100

0

100

200

300

400

500

L (PPM)

H (kAm)

9 kAm

12 kAm

16 kAm

20 kAm

24 kAm

38 kAm

Magnetostrictive displacement sensor

Hysteresis loops under

tensile stress σ

(a) Crystalline 68 NiFe

λs = +25 10-6

(b) crystalline pure Ni λs

= -35 10-6

Villari Effect ( Inverse of Joule Effect)

= -35 10-6

(c) amorphous Co-based

alloy

λs = -35 10-6

ϕσλ 2sin2

3sdotsdot= smeE

γ

Permeability depending on the stress

σλmicromicro

1

3

2

Y

J

so

s

r =

γ

Calculated magnetization curves under stress

Variation of magnetization curve by an applied

tensile force (Co-based amorphous alloy)

Alloy Requirement

Materials for magnetoelastic sensors

Why amorphous magnetic materials are important

Stress-strain curves of several materials

Coercivity and hardness of several materials

Principles of magnetoelastic sensors

Non-contact torque sensor

Principle of cross torductor torque

sensor and flux pattern of sensor

poles on the surface of a shaft

a) without and b)with torsional load

Equivalent magnetic circuit of

cross type torque sensor

Helices of principal tensile and compressive stress on the surface of

a shaft subjected to torsion [32] Correlated changes of permeability

are detected by four-branch yoke system with sensing coils 123

and 4 and a common excitation pole

Examples of torque sensors

Four-branch type torque sensor

heads Pole structures realized

by commercial multi-pole

ferrites 14 and 18 min in

diameter (diameter of sensor

h e a d 1 7 a n d 2 4 m m

respectively) respectively)

Principle of Ring Torductor torque transducer

(a b) Physical structure (c) evolution of the

shaft surface under the transducer poles A and BRing torductor for measuring

torque on ship propeller shafts

(shaft diameter ca 500 mm)

(Courtesy ASEA Brown

Boveri AG)

Principal designs of coaxial torque sensors

Schematic diagram of data processing

electronics of a torque sensor

Extensometer (a) Construction of strain sensing element using

amorphous ribbon wound core (b) configuration of lumped

windings

∆E effect of an amorphous FeNi-based

alloy (Fe40 Ni38 Mo4 B18) Hs saturation

field

Magnetically tunable delay line

Torque Sensors using Amorphous wire

Sixtus tonk효과(large Barkhausen효과)

Hysteresis loops of a Wiegand wire for different reset fields

Curie 온도 및Hopkinson효과

Relation between normalised

saturation polarisation and

normalised Curie temperature

Permeability of a Mn-Zn ferrite as

a function of temperature and field

strength

Conclusions

1) Magnetic sensor 는 자동차 공장자동화 항공우주 및 군사용으로많이 사용되고 있다

2) 새로운 소재개발은 자기센서의 성능개발에 직접적인 영향을 준다2) 새로운 소재개발은 자기센서의 성능개발에 직접적인 영향을 준다

3) 센서의 개발을 위해서는 다양한 전공지식이 요구된다

(물리학 재료공학 기계공학 전자공학)

4) 센서분야가 고부가가치를 창출하는 부품사업이다

5) 핵심부품을 생산하는 중소기업의 item으로도 적절하다

Reference Material (1) Normal defects and PVCs

Longitudinal and transverse defects

Def W L D Remarks

1 02 500 0213 (20 ) Inner defects

2 02 500 0427 (40 )

3 02 500 0213 (20 )Outer defectsPVC(1018)4 02 500 0427 (40 )

5 02 500 0639 (60 )

6 02 500 0852 (80 )

7 02 500 0639 (60 ) Inner defects

8 02 500 0852 (80 )

- 1 and 2 are inner defects

- 345 and 6 are outer defects with PVC

- 7 and 8 are inner defects

PVC

PVC

Defect Defect

For longitudinal defects and PVC For circumferential defects and PVC

ECT is very difficult to detect circumferential defects

We can distinguish PVCs and defects and longitudinal and circumferential defects

Flux-gate Magnetometer

One core sensor Two core sensor

3-축 flux-gate Magnetometer의 계략도

Sensorpia Co

pro

cess

or(

AV

R)

Sensor 1

RS422

Interface

Mic

ro-p

roce

ssor(

AV

R)

Sensor 2

Sensor 3

Interface

조립된 마그네토미터의 사진

Sensorpia Co

Analog PCB

Digital PCB

Sensorpia Co선형도(linearity)

10

20

30

40

50

60

y-axis

Magnetometer Output (microT)

-60 -50 -40 -30 -20 -10 0 10 20 30 40 50 60

-60

-50

-40

-30

-20

-10

0

10

Y-axis y=099946 x+0015STD 106E-4

Magnetometer Output (

Applied Magnetic Field (microT)

마그네토미터의 noise 특성 Sensorpia Co

1

10

100

y-axis

Magnetometer noise (nT)

0 1 2 3 4 5 6

1E-4

1E-3

001

01

Magnetometer noise (nT)

Frequency (Hz)

Magnetometer for KoDSAT

-150 -100 -50 0 50 100 150

-15

-10

-5

0

5

10

15

Magnetic Moment (Am

2)

Current (mA)

After Thermal Cycle Test

Measured

Resistance 193 ohm

Photograph of Magnetic torquer

Photograph of KoDSAT

Photograph of

3-axis Fluxgate

Magnetometer

Photograph of Magnetic torquer

Application of magnetometer

Moon magnetic fieldmeasurement

Telescope with direction indication

Joule Effect (Magnetostriction)

ϕ2cosel

l=

∆

0=∆

+∆

+∆

b

b

a

a

l

l

Actuator using Terfenol-D

00

05

10

B (T)

800

1000

1200

1400

1600

Magnetostriction (ppm)

-100 -50 0 50 100

-10

-05

00

B (T)

H (kAm)

2 MPa

4 MPa

6 MPa

8 MPa

10 MPa

12 MPa

-100 -50 0 50 100

-200

0

200

400

600

Magnetostriction (ppm)

H (kAm)

2 MPa

4 MPa

6 MPa

8 MPa

10 MPa

12 MPa

600

700

800

900

1000

-4 -3 -2 -1 0 1 2 3 4

0

10

20

30

40

50

60

Displacement (m

icro meter)

I (A)

FIELD

9 kAm

12 kAm

16 kAm

20 kAm

24 kAm

38 kAm

-50 -40 -30 -20 -10 0 10 20 30 40 50

-100

0

100

200

300

400

500

L (PPM)

H (kAm)

9 kAm

12 kAm

16 kAm

20 kAm

24 kAm

38 kAm

Magnetostrictive displacement sensor

Hysteresis loops under

tensile stress σ

(a) Crystalline 68 NiFe

λs = +25 10-6

(b) crystalline pure Ni λs

= -35 10-6

Villari Effect ( Inverse of Joule Effect)

= -35 10-6

(c) amorphous Co-based

alloy

λs = -35 10-6

ϕσλ 2sin2

3sdotsdot= smeE

γ

Permeability depending on the stress

σλmicromicro

1

3

2

Y

J

so

s

r =

γ

Calculated magnetization curves under stress

Variation of magnetization curve by an applied

tensile force (Co-based amorphous alloy)

Alloy Requirement

Materials for magnetoelastic sensors

Why amorphous magnetic materials are important

Stress-strain curves of several materials

Coercivity and hardness of several materials

Principles of magnetoelastic sensors

Non-contact torque sensor

Principle of cross torductor torque

sensor and flux pattern of sensor

poles on the surface of a shaft

a) without and b)with torsional load

Equivalent magnetic circuit of

cross type torque sensor

Helices of principal tensile and compressive stress on the surface of

a shaft subjected to torsion [32] Correlated changes of permeability

are detected by four-branch yoke system with sensing coils 123

and 4 and a common excitation pole

Examples of torque sensors

Four-branch type torque sensor

heads Pole structures realized

by commercial multi-pole

ferrites 14 and 18 min in

diameter (diameter of sensor

h e a d 1 7 a n d 2 4 m m

respectively) respectively)

Principle of Ring Torductor torque transducer

(a b) Physical structure (c) evolution of the

shaft surface under the transducer poles A and BRing torductor for measuring

torque on ship propeller shafts

(shaft diameter ca 500 mm)

(Courtesy ASEA Brown

Boveri AG)

Principal designs of coaxial torque sensors

Schematic diagram of data processing

electronics of a torque sensor

Extensometer (a) Construction of strain sensing element using

amorphous ribbon wound core (b) configuration of lumped

windings

∆E effect of an amorphous FeNi-based

alloy (Fe40 Ni38 Mo4 B18) Hs saturation

field

Magnetically tunable delay line

Torque Sensors using Amorphous wire

Sixtus tonk효과(large Barkhausen효과)

Hysteresis loops of a Wiegand wire for different reset fields

Curie 온도 및Hopkinson효과

Relation between normalised

saturation polarisation and

normalised Curie temperature

Permeability of a Mn-Zn ferrite as

a function of temperature and field

strength

Conclusions

1) Magnetic sensor 는 자동차 공장자동화 항공우주 및 군사용으로많이 사용되고 있다

2) 새로운 소재개발은 자기센서의 성능개발에 직접적인 영향을 준다2) 새로운 소재개발은 자기센서의 성능개발에 직접적인 영향을 준다

3) 센서의 개발을 위해서는 다양한 전공지식이 요구된다

(물리학 재료공학 기계공학 전자공학)

4) 센서분야가 고부가가치를 창출하는 부품사업이다

5) 핵심부품을 생산하는 중소기업의 item으로도 적절하다

PVC

PVC

Defect Defect

For longitudinal defects and PVC For circumferential defects and PVC

ECT is very difficult to detect circumferential defects

We can distinguish PVCs and defects and longitudinal and circumferential defects

Flux-gate Magnetometer

One core sensor Two core sensor

3-축 flux-gate Magnetometer의 계략도

Sensorpia Co

pro

cess

or(

AV

R)

Sensor 1

RS422

Interface

Mic

ro-p

roce

ssor(

AV

R)

Sensor 2

Sensor 3

Interface

조립된 마그네토미터의 사진

Sensorpia Co

Analog PCB

Digital PCB

Sensorpia Co선형도(linearity)

10

20

30

40

50

60

y-axis

Magnetometer Output (microT)

-60 -50 -40 -30 -20 -10 0 10 20 30 40 50 60

-60

-50

-40

-30

-20

-10

0

10

Y-axis y=099946 x+0015STD 106E-4

Magnetometer Output (

Applied Magnetic Field (microT)

마그네토미터의 noise 특성 Sensorpia Co

1

10

100

y-axis

Magnetometer noise (nT)

0 1 2 3 4 5 6

1E-4

1E-3

001

01

Magnetometer noise (nT)

Frequency (Hz)

Magnetometer for KoDSAT

-150 -100 -50 0 50 100 150

-15

-10

-5

0

5

10

15

Magnetic Moment (Am

2)

Current (mA)

After Thermal Cycle Test

Measured

Resistance 193 ohm

Photograph of Magnetic torquer

Photograph of KoDSAT

Photograph of

3-axis Fluxgate

Magnetometer

Photograph of Magnetic torquer

Application of magnetometer

Moon magnetic fieldmeasurement

Telescope with direction indication

Joule Effect (Magnetostriction)

ϕ2cosel

l=

∆

0=∆

+∆

+∆

b

b

a

a

l

l

Actuator using Terfenol-D

00

05

10

B (T)

800

1000

1200

1400

1600

Magnetostriction (ppm)

-100 -50 0 50 100

-10

-05

00

B (T)

H (kAm)

2 MPa

4 MPa

6 MPa

8 MPa

10 MPa

12 MPa

-100 -50 0 50 100

-200

0

200

400

600

Magnetostriction (ppm)

H (kAm)

2 MPa

4 MPa

6 MPa

8 MPa

10 MPa

12 MPa

600

700

800

900

1000

-4 -3 -2 -1 0 1 2 3 4

0

10

20

30

40

50

60

Displacement (m

icro meter)

I (A)

FIELD

9 kAm

12 kAm

16 kAm

20 kAm

24 kAm

38 kAm

-50 -40 -30 -20 -10 0 10 20 30 40 50

-100

0

100

200

300

400

500

L (PPM)

H (kAm)

9 kAm

12 kAm

16 kAm

20 kAm

24 kAm

38 kAm

Magnetostrictive displacement sensor

Hysteresis loops under

tensile stress σ

(a) Crystalline 68 NiFe

λs = +25 10-6

(b) crystalline pure Ni λs

= -35 10-6

Villari Effect ( Inverse of Joule Effect)

= -35 10-6

(c) amorphous Co-based

alloy

λs = -35 10-6

ϕσλ 2sin2

3sdotsdot= smeE

γ

Permeability depending on the stress

σλmicromicro

1

3

2

Y

J

so

s

r =

γ

Calculated magnetization curves under stress

Variation of magnetization curve by an applied

tensile force (Co-based amorphous alloy)

Alloy Requirement

Materials for magnetoelastic sensors

Why amorphous magnetic materials are important

Stress-strain curves of several materials

Coercivity and hardness of several materials

Principles of magnetoelastic sensors

Non-contact torque sensor

Principle of cross torductor torque

sensor and flux pattern of sensor

poles on the surface of a shaft

a) without and b)with torsional load

Equivalent magnetic circuit of

cross type torque sensor

Helices of principal tensile and compressive stress on the surface of

a shaft subjected to torsion [32] Correlated changes of permeability

are detected by four-branch yoke system with sensing coils 123

and 4 and a common excitation pole

Examples of torque sensors

Four-branch type torque sensor

heads Pole structures realized

by commercial multi-pole

ferrites 14 and 18 min in

diameter (diameter of sensor

h e a d 1 7 a n d 2 4 m m

respectively) respectively)

Principle of Ring Torductor torque transducer

(a b) Physical structure (c) evolution of the

shaft surface under the transducer poles A and BRing torductor for measuring

torque on ship propeller shafts

(shaft diameter ca 500 mm)

(Courtesy ASEA Brown

Boveri AG)

Principal designs of coaxial torque sensors

Schematic diagram of data processing

electronics of a torque sensor

Extensometer (a) Construction of strain sensing element using

amorphous ribbon wound core (b) configuration of lumped

windings

∆E effect of an amorphous FeNi-based

alloy (Fe40 Ni38 Mo4 B18) Hs saturation

field

Magnetically tunable delay line

Torque Sensors using Amorphous wire

Sixtus tonk효과(large Barkhausen효과)

Hysteresis loops of a Wiegand wire for different reset fields

Curie 온도 및Hopkinson효과

Relation between normalised

saturation polarisation and

normalised Curie temperature

Permeability of a Mn-Zn ferrite as

a function of temperature and field

strength

Conclusions

1) Magnetic sensor 는 자동차 공장자동화 항공우주 및 군사용으로많이 사용되고 있다

2) 새로운 소재개발은 자기센서의 성능개발에 직접적인 영향을 준다2) 새로운 소재개발은 자기센서의 성능개발에 직접적인 영향을 준다

3) 센서의 개발을 위해서는 다양한 전공지식이 요구된다

(물리학 재료공학 기계공학 전자공학)

4) 센서분야가 고부가가치를 창출하는 부품사업이다

5) 핵심부품을 생산하는 중소기업의 item으로도 적절하다

Flux-gate Magnetometer

One core sensor Two core sensor

3-축 flux-gate Magnetometer의 계략도

Sensorpia Co

pro

cess

or(

AV

R)

Sensor 1

RS422

Interface

Mic

ro-p

roce

ssor(

AV

R)

Sensor 2

Sensor 3

Interface

조립된 마그네토미터의 사진

Sensorpia Co

Analog PCB

Digital PCB

Sensorpia Co선형도(linearity)

10

20

30

40

50

60

y-axis

Magnetometer Output (microT)

-60 -50 -40 -30 -20 -10 0 10 20 30 40 50 60

-60

-50

-40

-30

-20

-10

0

10

Y-axis y=099946 x+0015STD 106E-4

Magnetometer Output (

Applied Magnetic Field (microT)

마그네토미터의 noise 특성 Sensorpia Co

1

10

100

y-axis

Magnetometer noise (nT)

0 1 2 3 4 5 6

1E-4

1E-3

001

01

Magnetometer noise (nT)

Frequency (Hz)

Magnetometer for KoDSAT

-150 -100 -50 0 50 100 150

-15

-10

-5

0

5

10

15

Magnetic Moment (Am

2)

Current (mA)

After Thermal Cycle Test

Measured

Resistance 193 ohm

Photograph of Magnetic torquer

Photograph of KoDSAT

Photograph of

3-axis Fluxgate

Magnetometer

Photograph of Magnetic torquer

Application of magnetometer

Moon magnetic fieldmeasurement

Telescope with direction indication

Joule Effect (Magnetostriction)

ϕ2cosel

l=

∆

0=∆

+∆

+∆

b

b

a

a

l

l

Actuator using Terfenol-D

00

05

10

B (T)

800

1000

1200

1400

1600

Magnetostriction (ppm)

-100 -50 0 50 100

-10

-05

00

B (T)

H (kAm)

2 MPa

4 MPa

6 MPa

8 MPa

10 MPa

12 MPa

-100 -50 0 50 100

-200

0

200

400

600

Magnetostriction (ppm)

H (kAm)

2 MPa

4 MPa

6 MPa

8 MPa

10 MPa

12 MPa

600

700

800

900

1000

-4 -3 -2 -1 0 1 2 3 4

0

10

20

30

40

50

60

Displacement (m

icro meter)

I (A)

FIELD

9 kAm

12 kAm

16 kAm

20 kAm

24 kAm

38 kAm

-50 -40 -30 -20 -10 0 10 20 30 40 50

-100

0

100

200

300

400

500

L (PPM)

H (kAm)

9 kAm

12 kAm

16 kAm

20 kAm

24 kAm

38 kAm

Magnetostrictive displacement sensor

Hysteresis loops under

tensile stress σ

(a) Crystalline 68 NiFe

λs = +25 10-6

(b) crystalline pure Ni λs

= -35 10-6

Villari Effect ( Inverse of Joule Effect)

= -35 10-6

(c) amorphous Co-based

alloy

λs = -35 10-6

ϕσλ 2sin2

3sdotsdot= smeE

γ

Permeability depending on the stress

σλmicromicro

1

3

2

Y

J

so

s

r =

γ

Calculated magnetization curves under stress

Variation of magnetization curve by an applied

tensile force (Co-based amorphous alloy)

Alloy Requirement

Materials for magnetoelastic sensors

Why amorphous magnetic materials are important

Stress-strain curves of several materials

Coercivity and hardness of several materials

Principles of magnetoelastic sensors

Non-contact torque sensor

Principle of cross torductor torque

sensor and flux pattern of sensor

poles on the surface of a shaft

a) without and b)with torsional load

Equivalent magnetic circuit of

cross type torque sensor

Helices of principal tensile and compressive stress on the surface of

a shaft subjected to torsion [32] Correlated changes of permeability

are detected by four-branch yoke system with sensing coils 123

and 4 and a common excitation pole

Examples of torque sensors

Four-branch type torque sensor

heads Pole structures realized

by commercial multi-pole

ferrites 14 and 18 min in

diameter (diameter of sensor

h e a d 1 7 a n d 2 4 m m

respectively) respectively)

Principle of Ring Torductor torque transducer

(a b) Physical structure (c) evolution of the

shaft surface under the transducer poles A and BRing torductor for measuring

torque on ship propeller shafts

(shaft diameter ca 500 mm)

(Courtesy ASEA Brown

Boveri AG)

Principal designs of coaxial torque sensors

Schematic diagram of data processing

electronics of a torque sensor

Extensometer (a) Construction of strain sensing element using

amorphous ribbon wound core (b) configuration of lumped

windings

∆E effect of an amorphous FeNi-based

alloy (Fe40 Ni38 Mo4 B18) Hs saturation

field

Magnetically tunable delay line

Torque Sensors using Amorphous wire

Sixtus tonk효과(large Barkhausen효과)

Hysteresis loops of a Wiegand wire for different reset fields

Curie 온도 및Hopkinson효과

Relation between normalised

saturation polarisation and

normalised Curie temperature

Permeability of a Mn-Zn ferrite as

a function of temperature and field

strength

Conclusions

1) Magnetic sensor 는 자동차 공장자동화 항공우주 및 군사용으로많이 사용되고 있다

2) 새로운 소재개발은 자기센서의 성능개발에 직접적인 영향을 준다2) 새로운 소재개발은 자기센서의 성능개발에 직접적인 영향을 준다

3) 센서의 개발을 위해서는 다양한 전공지식이 요구된다

(물리학 재료공학 기계공학 전자공학)

4) 센서분야가 고부가가치를 창출하는 부품사업이다

5) 핵심부품을 생산하는 중소기업의 item으로도 적절하다

3-축 flux-gate Magnetometer의 계략도

Sensorpia Co

pro

cess

or(

AV

R)

Sensor 1

RS422

Interface

Mic

ro-p

roce

ssor(

AV

R)

Sensor 2

Sensor 3

Interface

조립된 마그네토미터의 사진

Sensorpia Co

Analog PCB

Digital PCB

Sensorpia Co선형도(linearity)

10

20

30

40

50

60

y-axis

Magnetometer Output (microT)

-60 -50 -40 -30 -20 -10 0 10 20 30 40 50 60

-60

-50

-40

-30

-20

-10

0

10

Y-axis y=099946 x+0015STD 106E-4

Magnetometer Output (

Applied Magnetic Field (microT)

마그네토미터의 noise 특성 Sensorpia Co

1

10

100

y-axis

Magnetometer noise (nT)

0 1 2 3 4 5 6

1E-4

1E-3

001

01

Magnetometer noise (nT)

Frequency (Hz)

Magnetometer for KoDSAT

-150 -100 -50 0 50 100 150

-15

-10

-5

0

5

10

15

Magnetic Moment (Am

2)

Current (mA)

After Thermal Cycle Test

Measured

Resistance 193 ohm

Photograph of Magnetic torquer

Photograph of KoDSAT

Photograph of

3-axis Fluxgate

Magnetometer

Photograph of Magnetic torquer

Application of magnetometer

Moon magnetic fieldmeasurement

Telescope with direction indication

Joule Effect (Magnetostriction)

ϕ2cosel

l=

∆

0=∆

+∆

+∆

b

b

a

a

l

l

Actuator using Terfenol-D

00

05

10

B (T)

800

1000

1200

1400

1600

Magnetostriction (ppm)

-100 -50 0 50 100

-10

-05

00

B (T)

H (kAm)

2 MPa

4 MPa

6 MPa

8 MPa

10 MPa

12 MPa

-100 -50 0 50 100

-200

0

200

400

600

Magnetostriction (ppm)

H (kAm)

2 MPa

4 MPa

6 MPa

8 MPa

10 MPa

12 MPa

600

700

800

900

1000

-4 -3 -2 -1 0 1 2 3 4

0

10

20

30

40

50

60

Displacement (m

icro meter)

I (A)

FIELD

9 kAm

12 kAm

16 kAm

20 kAm

24 kAm

38 kAm

-50 -40 -30 -20 -10 0 10 20 30 40 50

-100

0

100

200

300

400

500

L (PPM)

H (kAm)

9 kAm

12 kAm

16 kAm

20 kAm

24 kAm

38 kAm

Magnetostrictive displacement sensor

Hysteresis loops under

tensile stress σ

(a) Crystalline 68 NiFe

λs = +25 10-6

(b) crystalline pure Ni λs

= -35 10-6

Villari Effect ( Inverse of Joule Effect)

= -35 10-6

(c) amorphous Co-based

alloy

λs = -35 10-6

ϕσλ 2sin2

3sdotsdot= smeE

γ

Permeability depending on the stress

σλmicromicro

1

3

2

Y

J

so

s

r =

γ

Calculated magnetization curves under stress

Variation of magnetization curve by an applied

tensile force (Co-based amorphous alloy)

Alloy Requirement

Materials for magnetoelastic sensors

Why amorphous magnetic materials are important

Stress-strain curves of several materials

Coercivity and hardness of several materials

Principles of magnetoelastic sensors

Non-contact torque sensor

Principle of cross torductor torque

sensor and flux pattern of sensor

poles on the surface of a shaft

a) without and b)with torsional load

Equivalent magnetic circuit of

cross type torque sensor

Helices of principal tensile and compressive stress on the surface of

a shaft subjected to torsion [32] Correlated changes of permeability

are detected by four-branch yoke system with sensing coils 123

and 4 and a common excitation pole

Examples of torque sensors

Four-branch type torque sensor

heads Pole structures realized

by commercial multi-pole

ferrites 14 and 18 min in

diameter (diameter of sensor

h e a d 1 7 a n d 2 4 m m

respectively) respectively)

Principle of Ring Torductor torque transducer

(a b) Physical structure (c) evolution of the

shaft surface under the transducer poles A and BRing torductor for measuring

torque on ship propeller shafts

(shaft diameter ca 500 mm)

(Courtesy ASEA Brown

Boveri AG)

Principal designs of coaxial torque sensors

Schematic diagram of data processing

electronics of a torque sensor

Extensometer (a) Construction of strain sensing element using

amorphous ribbon wound core (b) configuration of lumped

windings

∆E effect of an amorphous FeNi-based

alloy (Fe40 Ni38 Mo4 B18) Hs saturation

field

Magnetically tunable delay line

Torque Sensors using Amorphous wire

Sixtus tonk효과(large Barkhausen효과)

Hysteresis loops of a Wiegand wire for different reset fields

Curie 온도 및Hopkinson효과

Relation between normalised

saturation polarisation and

normalised Curie temperature

Permeability of a Mn-Zn ferrite as

a function of temperature and field

strength

Conclusions

1) Magnetic sensor 는 자동차 공장자동화 항공우주 및 군사용으로많이 사용되고 있다

2) 새로운 소재개발은 자기센서의 성능개발에 직접적인 영향을 준다2) 새로운 소재개발은 자기센서의 성능개발에 직접적인 영향을 준다

3) 센서의 개발을 위해서는 다양한 전공지식이 요구된다

(물리학 재료공학 기계공학 전자공학)

4) 센서분야가 고부가가치를 창출하는 부품사업이다

5) 핵심부품을 생산하는 중소기업의 item으로도 적절하다

조립된 마그네토미터의 사진

Sensorpia Co

Analog PCB

Digital PCB

Sensorpia Co선형도(linearity)

10

20

30

40

50

60

y-axis

Magnetometer Output (microT)

-60 -50 -40 -30 -20 -10 0 10 20 30 40 50 60

-60

-50

-40

-30

-20

-10

0

10

Y-axis y=099946 x+0015STD 106E-4

Magnetometer Output (

Applied Magnetic Field (microT)

마그네토미터의 noise 특성 Sensorpia Co

1

10

100

y-axis

Magnetometer noise (nT)

0 1 2 3 4 5 6

1E-4

1E-3

001

01

Magnetometer noise (nT)

Frequency (Hz)

Magnetometer for KoDSAT

-150 -100 -50 0 50 100 150

-15

-10

-5

0

5

10

15

Magnetic Moment (Am

2)

Current (mA)

After Thermal Cycle Test

Measured

Resistance 193 ohm

Photograph of Magnetic torquer

Photograph of KoDSAT

Photograph of

3-axis Fluxgate

Magnetometer

Photograph of Magnetic torquer

Application of magnetometer

Moon magnetic fieldmeasurement

Telescope with direction indication

Joule Effect (Magnetostriction)

ϕ2cosel

l=

∆

0=∆

+∆

+∆

b

b

a

a

l

l

Actuator using Terfenol-D

00

05

10

B (T)

800

1000

1200

1400

1600

Magnetostriction (ppm)

-100 -50 0 50 100

-10

-05

00

B (T)

H (kAm)

2 MPa

4 MPa

6 MPa

8 MPa

10 MPa

12 MPa

-100 -50 0 50 100

-200

0

200

400

600

Magnetostriction (ppm)

H (kAm)

2 MPa

4 MPa

6 MPa

8 MPa

10 MPa

12 MPa

600

700

800

900

1000

-4 -3 -2 -1 0 1 2 3 4

0

10

20

30

40

50

60

Displacement (m

icro meter)

I (A)

FIELD

9 kAm

12 kAm

16 kAm

20 kAm

24 kAm

38 kAm

-50 -40 -30 -20 -10 0 10 20 30 40 50

-100

0

100

200

300

400

500

L (PPM)

H (kAm)

9 kAm

12 kAm

16 kAm

20 kAm

24 kAm

38 kAm

Magnetostrictive displacement sensor

Hysteresis loops under

tensile stress σ

(a) Crystalline 68 NiFe

λs = +25 10-6

(b) crystalline pure Ni λs

= -35 10-6

Villari Effect ( Inverse of Joule Effect)

= -35 10-6

(c) amorphous Co-based

alloy

λs = -35 10-6

ϕσλ 2sin2

3sdotsdot= smeE

γ

Permeability depending on the stress

σλmicromicro

1

3

2

Y

J

so

s

r =

γ

Calculated magnetization curves under stress

Variation of magnetization curve by an applied

tensile force (Co-based amorphous alloy)

Alloy Requirement

Materials for magnetoelastic sensors

Why amorphous magnetic materials are important

Stress-strain curves of several materials

Coercivity and hardness of several materials

Principles of magnetoelastic sensors

Non-contact torque sensor

Principle of cross torductor torque

sensor and flux pattern of sensor

poles on the surface of a shaft

a) without and b)with torsional load

Equivalent magnetic circuit of

cross type torque sensor

Helices of principal tensile and compressive stress on the surface of

a shaft subjected to torsion [32] Correlated changes of permeability

are detected by four-branch yoke system with sensing coils 123

and 4 and a common excitation pole

Examples of torque sensors

Four-branch type torque sensor

heads Pole structures realized

by commercial multi-pole

ferrites 14 and 18 min in

diameter (diameter of sensor

h e a d 1 7 a n d 2 4 m m

respectively) respectively)

Principle of Ring Torductor torque transducer

(a b) Physical structure (c) evolution of the

shaft surface under the transducer poles A and BRing torductor for measuring

torque on ship propeller shafts

(shaft diameter ca 500 mm)

(Courtesy ASEA Brown

Boveri AG)

Principal designs of coaxial torque sensors

Schematic diagram of data processing

electronics of a torque sensor

Extensometer (a) Construction of strain sensing element using

amorphous ribbon wound core (b) configuration of lumped

windings

∆E effect of an amorphous FeNi-based

alloy (Fe40 Ni38 Mo4 B18) Hs saturation

field

Magnetically tunable delay line

Torque Sensors using Amorphous wire

Sixtus tonk효과(large Barkhausen효과)

Hysteresis loops of a Wiegand wire for different reset fields

Curie 온도 및Hopkinson효과

Relation between normalised

saturation polarisation and

normalised Curie temperature

Permeability of a Mn-Zn ferrite as

a function of temperature and field

strength

Conclusions

1) Magnetic sensor 는 자동차 공장자동화 항공우주 및 군사용으로많이 사용되고 있다

2) 새로운 소재개발은 자기센서의 성능개발에 직접적인 영향을 준다2) 새로운 소재개발은 자기센서의 성능개발에 직접적인 영향을 준다

3) 센서의 개발을 위해서는 다양한 전공지식이 요구된다

(물리학 재료공학 기계공학 전자공학)

4) 센서분야가 고부가가치를 창출하는 부품사업이다

5) 핵심부품을 생산하는 중소기업의 item으로도 적절하다

Sensorpia Co선형도(linearity)

10

20

30

40

50

60

y-axis

Magnetometer Output (microT)

-60 -50 -40 -30 -20 -10 0 10 20 30 40 50 60

-60

-50

-40

-30

-20

-10

0

10

Y-axis y=099946 x+0015STD 106E-4

Magnetometer Output (

Applied Magnetic Field (microT)

마그네토미터의 noise 특성 Sensorpia Co

1

10

100

y-axis

Magnetometer noise (nT)

0 1 2 3 4 5 6

1E-4

1E-3

001

01

Magnetometer noise (nT)

Frequency (Hz)

Magnetometer for KoDSAT

-150 -100 -50 0 50 100 150

-15

-10

-5

0

5

10

15

Magnetic Moment (Am

2)

Current (mA)

After Thermal Cycle Test

Measured

Resistance 193 ohm

Photograph of Magnetic torquer

Photograph of KoDSAT

Photograph of

3-axis Fluxgate

Magnetometer

Photograph of Magnetic torquer

Application of magnetometer

Moon magnetic fieldmeasurement

Telescope with direction indication

Joule Effect (Magnetostriction)

ϕ2cosel

l=

∆

0=∆

+∆

+∆

b

b

a

a

l

l

Actuator using Terfenol-D

00

05

10

B (T)

800

1000

1200

1400

1600

Magnetostriction (ppm)

-100 -50 0 50 100

-10

-05

00

B (T)

H (kAm)

2 MPa

4 MPa

6 MPa

8 MPa

10 MPa

12 MPa

-100 -50 0 50 100

-200

0

200

400

600

Magnetostriction (ppm)

H (kAm)

2 MPa

4 MPa

6 MPa

8 MPa

10 MPa

12 MPa

600

700

800

900

1000

-4 -3 -2 -1 0 1 2 3 4

0

10

20

30

40

50

60

Displacement (m

icro meter)

I (A)

FIELD

9 kAm

12 kAm

16 kAm

20 kAm

24 kAm

38 kAm

-50 -40 -30 -20 -10 0 10 20 30 40 50

-100

0

100

200

300

400

500

L (PPM)

H (kAm)

9 kAm

12 kAm

16 kAm

20 kAm

24 kAm

38 kAm

Magnetostrictive displacement sensor

Hysteresis loops under

tensile stress σ

(a) Crystalline 68 NiFe

λs = +25 10-6

(b) crystalline pure Ni λs

= -35 10-6

Villari Effect ( Inverse of Joule Effect)

= -35 10-6

(c) amorphous Co-based

alloy

λs = -35 10-6

ϕσλ 2sin2

3sdotsdot= smeE

γ

Permeability depending on the stress

σλmicromicro

1

3

2

Y

J

so

s

r =

γ

Calculated magnetization curves under stress

Variation of magnetization curve by an applied

tensile force (Co-based amorphous alloy)

Alloy Requirement

Materials for magnetoelastic sensors

Why amorphous magnetic materials are important

Stress-strain curves of several materials

Coercivity and hardness of several materials

Principles of magnetoelastic sensors

Non-contact torque sensor

Principle of cross torductor torque

sensor and flux pattern of sensor

poles on the surface of a shaft

a) without and b)with torsional load

Equivalent magnetic circuit of

cross type torque sensor

Helices of principal tensile and compressive stress on the surface of

a shaft subjected to torsion [32] Correlated changes of permeability

are detected by four-branch yoke system with sensing coils 123

and 4 and a common excitation pole

Examples of torque sensors

Four-branch type torque sensor

heads Pole structures realized

by commercial multi-pole

ferrites 14 and 18 min in

diameter (diameter of sensor

h e a d 1 7 a n d 2 4 m m

respectively) respectively)

Principle of Ring Torductor torque transducer

(a b) Physical structure (c) evolution of the

shaft surface under the transducer poles A and BRing torductor for measuring

torque on ship propeller shafts

(shaft diameter ca 500 mm)

(Courtesy ASEA Brown

Boveri AG)

Principal designs of coaxial torque sensors

Schematic diagram of data processing

electronics of a torque sensor

Extensometer (a) Construction of strain sensing element using

amorphous ribbon wound core (b) configuration of lumped

windings

∆E effect of an amorphous FeNi-based

alloy (Fe40 Ni38 Mo4 B18) Hs saturation

field

Magnetically tunable delay line

Torque Sensors using Amorphous wire

Sixtus tonk효과(large Barkhausen효과)

Hysteresis loops of a Wiegand wire for different reset fields

Curie 온도 및Hopkinson효과

Relation between normalised

saturation polarisation and

normalised Curie temperature

Permeability of a Mn-Zn ferrite as

a function of temperature and field

strength

Conclusions

1) Magnetic sensor 는 자동차 공장자동화 항공우주 및 군사용으로많이 사용되고 있다

2) 새로운 소재개발은 자기센서의 성능개발에 직접적인 영향을 준다2) 새로운 소재개발은 자기센서의 성능개발에 직접적인 영향을 준다

3) 센서의 개발을 위해서는 다양한 전공지식이 요구된다

(물리학 재료공학 기계공학 전자공학)

4) 센서분야가 고부가가치를 창출하는 부품사업이다

5) 핵심부품을 생산하는 중소기업의 item으로도 적절하다

마그네토미터의 noise 특성 Sensorpia Co

1

10

100

y-axis

Magnetometer noise (nT)

0 1 2 3 4 5 6

1E-4

1E-3

001

01

Magnetometer noise (nT)

Frequency (Hz)

Magnetometer for KoDSAT

-150 -100 -50 0 50 100 150

-15

-10

-5

0

5

10

15

Magnetic Moment (Am

2)

Current (mA)

After Thermal Cycle Test

Measured

Resistance 193 ohm

Photograph of Magnetic torquer

Photograph of KoDSAT

Photograph of

3-axis Fluxgate

Magnetometer

Photograph of Magnetic torquer

Application of magnetometer

Moon magnetic fieldmeasurement

Telescope with direction indication

Joule Effect (Magnetostriction)

ϕ2cosel

l=

∆

0=∆

+∆

+∆

b

b

a

a

l

l

Actuator using Terfenol-D

00

05

10

B (T)

800

1000

1200

1400

1600

Magnetostriction (ppm)

-100 -50 0 50 100

-10

-05

00

B (T)

H (kAm)

2 MPa

4 MPa

6 MPa

8 MPa

10 MPa

12 MPa

-100 -50 0 50 100

-200

0

200

400

600

Magnetostriction (ppm)

H (kAm)

2 MPa

4 MPa

6 MPa

8 MPa

10 MPa

12 MPa

600

700

800

900

1000

-4 -3 -2 -1 0 1 2 3 4

0

10

20

30

40

50

60

Displacement (m

icro meter)

I (A)

FIELD

9 kAm

12 kAm

16 kAm

20 kAm

24 kAm

38 kAm

-50 -40 -30 -20 -10 0 10 20 30 40 50

-100

0

100

200

300

400

500

L (PPM)

H (kAm)

9 kAm

12 kAm

16 kAm

20 kAm

24 kAm

38 kAm

Magnetostrictive displacement sensor

Hysteresis loops under

tensile stress σ

(a) Crystalline 68 NiFe

λs = +25 10-6

(b) crystalline pure Ni λs

= -35 10-6

Villari Effect ( Inverse of Joule Effect)

= -35 10-6

(c) amorphous Co-based

alloy

λs = -35 10-6

ϕσλ 2sin2

3sdotsdot= smeE

γ

Permeability depending on the stress

σλmicromicro

1

3

2

Y

J

so

s

r =

γ

Calculated magnetization curves under stress

Variation of magnetization curve by an applied

tensile force (Co-based amorphous alloy)

Alloy Requirement

Materials for magnetoelastic sensors

Why amorphous magnetic materials are important

Stress-strain curves of several materials

Coercivity and hardness of several materials

Principles of magnetoelastic sensors

Non-contact torque sensor

Principle of cross torductor torque

sensor and flux pattern of sensor

poles on the surface of a shaft

a) without and b)with torsional load

Equivalent magnetic circuit of

cross type torque sensor

Helices of principal tensile and compressive stress on the surface of

a shaft subjected to torsion [32] Correlated changes of permeability

are detected by four-branch yoke system with sensing coils 123

and 4 and a common excitation pole

Examples of torque sensors

Four-branch type torque sensor

heads Pole structures realized

by commercial multi-pole

ferrites 14 and 18 min in

diameter (diameter of sensor

h e a d 1 7 a n d 2 4 m m

respectively) respectively)

Principle of Ring Torductor torque transducer

(a b) Physical structure (c) evolution of the

shaft surface under the transducer poles A and BRing torductor for measuring

torque on ship propeller shafts

(shaft diameter ca 500 mm)

(Courtesy ASEA Brown

Boveri AG)

Principal designs of coaxial torque sensors

Schematic diagram of data processing

electronics of a torque sensor

Extensometer (a) Construction of strain sensing element using

amorphous ribbon wound core (b) configuration of lumped

windings

∆E effect of an amorphous FeNi-based

alloy (Fe40 Ni38 Mo4 B18) Hs saturation

field

Magnetically tunable delay line

Torque Sensors using Amorphous wire

Sixtus tonk효과(large Barkhausen효과)

Hysteresis loops of a Wiegand wire for different reset fields

Curie 온도 및Hopkinson효과

Relation between normalised

saturation polarisation and

normalised Curie temperature

Permeability of a Mn-Zn ferrite as

a function of temperature and field

strength

Conclusions

1) Magnetic sensor 는 자동차 공장자동화 항공우주 및 군사용으로많이 사용되고 있다

2) 새로운 소재개발은 자기센서의 성능개발에 직접적인 영향을 준다2) 새로운 소재개발은 자기센서의 성능개발에 직접적인 영향을 준다

3) 센서의 개발을 위해서는 다양한 전공지식이 요구된다

(물리학 재료공학 기계공학 전자공학)

4) 센서분야가 고부가가치를 창출하는 부품사업이다

5) 핵심부품을 생산하는 중소기업의 item으로도 적절하다

Magnetometer for KoDSAT

-150 -100 -50 0 50 100 150

-15

-10

-5

0

5

10

15

Magnetic Moment (Am

2)

Current (mA)

After Thermal Cycle Test

Measured

Resistance 193 ohm

Photograph of Magnetic torquer

Photograph of KoDSAT

Photograph of

3-axis Fluxgate

Magnetometer

Photograph of Magnetic torquer

Application of magnetometer

Moon magnetic fieldmeasurement

Telescope with direction indication

Joule Effect (Magnetostriction)

ϕ2cosel

l=

∆

0=∆

+∆

+∆

b

b

a

a

l

l

Actuator using Terfenol-D

00

05

10

B (T)

800

1000

1200

1400

1600

Magnetostriction (ppm)

-100 -50 0 50 100

-10

-05

00

B (T)

H (kAm)

2 MPa

4 MPa

6 MPa

8 MPa

10 MPa

12 MPa

-100 -50 0 50 100

-200

0

200

400

600

Magnetostriction (ppm)

H (kAm)

2 MPa

4 MPa

6 MPa

8 MPa

10 MPa

12 MPa

600

700

800

900

1000

-4 -3 -2 -1 0 1 2 3 4

0

10

20

30

40

50

60

Displacement (m

icro meter)

I (A)

FIELD

9 kAm

12 kAm

16 kAm

20 kAm

24 kAm

38 kAm

-50 -40 -30 -20 -10 0 10 20 30 40 50

-100

0

100

200

300

400

500

L (PPM)

H (kAm)

9 kAm

12 kAm

16 kAm

20 kAm

24 kAm

38 kAm

Magnetostrictive displacement sensor

Hysteresis loops under

tensile stress σ

(a) Crystalline 68 NiFe

λs = +25 10-6

(b) crystalline pure Ni λs

= -35 10-6

Villari Effect ( Inverse of Joule Effect)

= -35 10-6

(c) amorphous Co-based

alloy

λs = -35 10-6

ϕσλ 2sin2

3sdotsdot= smeE

γ

Permeability depending on the stress

σλmicromicro

1

3

2

Y

J

so

s

r =

γ

Calculated magnetization curves under stress

Variation of magnetization curve by an applied

tensile force (Co-based amorphous alloy)

Alloy Requirement

Materials for magnetoelastic sensors

Why amorphous magnetic materials are important

Stress-strain curves of several materials

Coercivity and hardness of several materials

Principles of magnetoelastic sensors

Non-contact torque sensor

Principle of cross torductor torque

sensor and flux pattern of sensor

poles on the surface of a shaft

a) without and b)with torsional load

Equivalent magnetic circuit of

cross type torque sensor

Helices of principal tensile and compressive stress on the surface of

a shaft subjected to torsion [32] Correlated changes of permeability

are detected by four-branch yoke system with sensing coils 123

and 4 and a common excitation pole

Examples of torque sensors

Four-branch type torque sensor

heads Pole structures realized

by commercial multi-pole

ferrites 14 and 18 min in

diameter (diameter of sensor

h e a d 1 7 a n d 2 4 m m

respectively) respectively)

Principle of Ring Torductor torque transducer

(a b) Physical structure (c) evolution of the

shaft surface under the transducer poles A and BRing torductor for measuring

torque on ship propeller shafts

(shaft diameter ca 500 mm)

(Courtesy ASEA Brown

Boveri AG)

Principal designs of coaxial torque sensors

Schematic diagram of data processing

electronics of a torque sensor

Extensometer (a) Construction of strain sensing element using

amorphous ribbon wound core (b) configuration of lumped

windings

∆E effect of an amorphous FeNi-based

alloy (Fe40 Ni38 Mo4 B18) Hs saturation

field

Magnetically tunable delay line

Torque Sensors using Amorphous wire

Sixtus tonk효과(large Barkhausen효과)

Hysteresis loops of a Wiegand wire for different reset fields

Curie 온도 및Hopkinson효과

Relation between normalised

saturation polarisation and

normalised Curie temperature

Permeability of a Mn-Zn ferrite as

a function of temperature and field

strength

Conclusions

1) Magnetic sensor 는 자동차 공장자동화 항공우주 및 군사용으로많이 사용되고 있다

2) 새로운 소재개발은 자기센서의 성능개발에 직접적인 영향을 준다2) 새로운 소재개발은 자기센서의 성능개발에 직접적인 영향을 준다

3) 센서의 개발을 위해서는 다양한 전공지식이 요구된다

(물리학 재료공학 기계공학 전자공학)

4) 센서분야가 고부가가치를 창출하는 부품사업이다

5) 핵심부품을 생산하는 중소기업의 item으로도 적절하다

Application of magnetometer

Moon magnetic fieldmeasurement

Telescope with direction indication

Joule Effect (Magnetostriction)

ϕ2cosel

l=

∆

0=∆

+∆

+∆

b

b

a

a

l

l

Actuator using Terfenol-D

00

05

10

B (T)

800

1000

1200

1400

1600

Magnetostriction (ppm)

-100 -50 0 50 100

-10

-05

00

B (T)

H (kAm)

2 MPa

4 MPa

6 MPa

8 MPa

10 MPa

12 MPa

-100 -50 0 50 100

-200

0

200

400

600

Magnetostriction (ppm)

H (kAm)

2 MPa

4 MPa

6 MPa

8 MPa

10 MPa

12 MPa

600

700

800

900

1000

-4 -3 -2 -1 0 1 2 3 4

0

10

20

30

40

50

60

Displacement (m

icro meter)

I (A)

FIELD

9 kAm

12 kAm

16 kAm

20 kAm

24 kAm

38 kAm

-50 -40 -30 -20 -10 0 10 20 30 40 50

-100

0

100

200

300

400

500

L (PPM)

H (kAm)

9 kAm

12 kAm

16 kAm

20 kAm

24 kAm

38 kAm

Magnetostrictive displacement sensor

Hysteresis loops under

tensile stress σ

(a) Crystalline 68 NiFe

λs = +25 10-6

(b) crystalline pure Ni λs

= -35 10-6

Villari Effect ( Inverse of Joule Effect)

= -35 10-6

(c) amorphous Co-based

alloy

λs = -35 10-6

ϕσλ 2sin2

3sdotsdot= smeE

γ

Permeability depending on the stress

σλmicromicro

1

3

2

Y

J

so

s

r =

γ

Calculated magnetization curves under stress

Variation of magnetization curve by an applied

tensile force (Co-based amorphous alloy)

Alloy Requirement

Materials for magnetoelastic sensors

Why amorphous magnetic materials are important

Stress-strain curves of several materials

Coercivity and hardness of several materials

Principles of magnetoelastic sensors

Non-contact torque sensor

Principle of cross torductor torque

sensor and flux pattern of sensor

poles on the surface of a shaft

a) without and b)with torsional load

Equivalent magnetic circuit of

cross type torque sensor

Helices of principal tensile and compressive stress on the surface of

a shaft subjected to torsion [32] Correlated changes of permeability

are detected by four-branch yoke system with sensing coils 123

and 4 and a common excitation pole

Examples of torque sensors

Four-branch type torque sensor

heads Pole structures realized

by commercial multi-pole

ferrites 14 and 18 min in

diameter (diameter of sensor

h e a d 1 7 a n d 2 4 m m

respectively) respectively)

Principle of Ring Torductor torque transducer

(a b) Physical structure (c) evolution of the

shaft surface under the transducer poles A and BRing torductor for measuring

torque on ship propeller shafts

(shaft diameter ca 500 mm)

(Courtesy ASEA Brown

Boveri AG)

Principal designs of coaxial torque sensors

Schematic diagram of data processing

electronics of a torque sensor

Extensometer (a) Construction of strain sensing element using

amorphous ribbon wound core (b) configuration of lumped

windings

∆E effect of an amorphous FeNi-based

alloy (Fe40 Ni38 Mo4 B18) Hs saturation

field

Magnetically tunable delay line

Torque Sensors using Amorphous wire

Sixtus tonk효과(large Barkhausen효과)

Hysteresis loops of a Wiegand wire for different reset fields

Curie 온도 및Hopkinson효과

Relation between normalised

saturation polarisation and

normalised Curie temperature

Permeability of a Mn-Zn ferrite as

a function of temperature and field

strength

Conclusions

1) Magnetic sensor 는 자동차 공장자동화 항공우주 및 군사용으로많이 사용되고 있다

2) 새로운 소재개발은 자기센서의 성능개발에 직접적인 영향을 준다2) 새로운 소재개발은 자기센서의 성능개발에 직접적인 영향을 준다

3) 센서의 개발을 위해서는 다양한 전공지식이 요구된다

(물리학 재료공학 기계공학 전자공학)

4) 센서분야가 고부가가치를 창출하는 부품사업이다

5) 핵심부품을 생산하는 중소기업의 item으로도 적절하다

Joule Effect (Magnetostriction)

ϕ2cosel

l=

∆

0=∆

+∆

+∆

b

b

a

a

l

l

Actuator using Terfenol-D

00

05

10

B (T)

800

1000

1200

1400

1600

Magnetostriction (ppm)

-100 -50 0 50 100

-10

-05

00

B (T)

H (kAm)

2 MPa

4 MPa

6 MPa

8 MPa

10 MPa

12 MPa

-100 -50 0 50 100

-200

0

200

400

600

Magnetostriction (ppm)

H (kAm)

2 MPa

4 MPa

6 MPa

8 MPa

10 MPa

12 MPa

600

700

800

900

1000

-4 -3 -2 -1 0 1 2 3 4

0

10

20

30

40

50

60

Displacement (m

icro meter)

I (A)

FIELD

9 kAm

12 kAm

16 kAm

20 kAm

24 kAm

38 kAm

-50 -40 -30 -20 -10 0 10 20 30 40 50

-100

0

100

200

300

400

500

L (PPM)

H (kAm)

9 kAm

12 kAm

16 kAm

20 kAm

24 kAm

38 kAm

Magnetostrictive displacement sensor

Hysteresis loops under

tensile stress σ

(a) Crystalline 68 NiFe

λs = +25 10-6

(b) crystalline pure Ni λs

= -35 10-6

Villari Effect ( Inverse of Joule Effect)

= -35 10-6

(c) amorphous Co-based

alloy

λs = -35 10-6

ϕσλ 2sin2

3sdotsdot= smeE

γ

Permeability depending on the stress

σλmicromicro

1

3

2

Y

J

so

s

r =

γ

Calculated magnetization curves under stress

Variation of magnetization curve by an applied

tensile force (Co-based amorphous alloy)

Alloy Requirement

Materials for magnetoelastic sensors

Why amorphous magnetic materials are important

Stress-strain curves of several materials

Coercivity and hardness of several materials

Principles of magnetoelastic sensors

Non-contact torque sensor

Principle of cross torductor torque

sensor and flux pattern of sensor

poles on the surface of a shaft

a) without and b)with torsional load

Equivalent magnetic circuit of

cross type torque sensor

Helices of principal tensile and compressive stress on the surface of

a shaft subjected to torsion [32] Correlated changes of permeability

are detected by four-branch yoke system with sensing coils 123

and 4 and a common excitation pole

Examples of torque sensors

Four-branch type torque sensor

heads Pole structures realized

by commercial multi-pole

ferrites 14 and 18 min in

diameter (diameter of sensor

h e a d 1 7 a n d 2 4 m m

respectively) respectively)

Principle of Ring Torductor torque transducer

(a b) Physical structure (c) evolution of the

shaft surface under the transducer poles A and BRing torductor for measuring

torque on ship propeller shafts

(shaft diameter ca 500 mm)

(Courtesy ASEA Brown

Boveri AG)

Principal designs of coaxial torque sensors

Schematic diagram of data processing

electronics of a torque sensor

Extensometer (a) Construction of strain sensing element using

amorphous ribbon wound core (b) configuration of lumped

windings

∆E effect of an amorphous FeNi-based

alloy (Fe40 Ni38 Mo4 B18) Hs saturation

field

Magnetically tunable delay line

Torque Sensors using Amorphous wire

Sixtus tonk효과(large Barkhausen효과)

Hysteresis loops of a Wiegand wire for different reset fields

Curie 온도 및Hopkinson효과

Relation between normalised

saturation polarisation and

normalised Curie temperature

Permeability of a Mn-Zn ferrite as

a function of temperature and field

strength

Conclusions

1) Magnetic sensor 는 자동차 공장자동화 항공우주 및 군사용으로많이 사용되고 있다

2) 새로운 소재개발은 자기센서의 성능개발에 직접적인 영향을 준다2) 새로운 소재개발은 자기센서의 성능개발에 직접적인 영향을 준다

3) 센서의 개발을 위해서는 다양한 전공지식이 요구된다

(물리학 재료공학 기계공학 전자공학)

4) 센서분야가 고부가가치를 창출하는 부품사업이다

5) 핵심부품을 생산하는 중소기업의 item으로도 적절하다

Actuator using Terfenol-D

00

05

10

B (T)

800

1000

1200

1400

1600

Magnetostriction (ppm)

-100 -50 0 50 100

-10

-05

00

B (T)

H (kAm)

2 MPa

4 MPa

6 MPa

8 MPa

10 MPa

12 MPa

-100 -50 0 50 100

-200

0

200

400

600

Magnetostriction (ppm)

H (kAm)

2 MPa

4 MPa

6 MPa

8 MPa

10 MPa

12 MPa

600

700

800

900

1000

-4 -3 -2 -1 0 1 2 3 4

0

10

20

30

40

50

60

Displacement (m

icro meter)

I (A)

FIELD

9 kAm

12 kAm

16 kAm

20 kAm

24 kAm

38 kAm

-50 -40 -30 -20 -10 0 10 20 30 40 50

-100

0

100

200

300

400

500

L (PPM)

H (kAm)

9 kAm

12 kAm

16 kAm

20 kAm

24 kAm

38 kAm

Magnetostrictive displacement sensor

Hysteresis loops under

tensile stress σ

(a) Crystalline 68 NiFe

λs = +25 10-6

(b) crystalline pure Ni λs

= -35 10-6

Villari Effect ( Inverse of Joule Effect)

= -35 10-6

(c) amorphous Co-based

alloy

λs = -35 10-6

ϕσλ 2sin2

3sdotsdot= smeE

γ

Permeability depending on the stress

σλmicromicro

1

3

2

Y

J

so

s

r =

γ

Calculated magnetization curves under stress

Variation of magnetization curve by an applied

tensile force (Co-based amorphous alloy)

Alloy Requirement

Materials for magnetoelastic sensors

Why amorphous magnetic materials are important

Stress-strain curves of several materials

Coercivity and hardness of several materials

Principles of magnetoelastic sensors

Non-contact torque sensor

Principle of cross torductor torque

sensor and flux pattern of sensor

poles on the surface of a shaft

a) without and b)with torsional load

Equivalent magnetic circuit of

cross type torque sensor

Helices of principal tensile and compressive stress on the surface of

a shaft subjected to torsion [32] Correlated changes of permeability

are detected by four-branch yoke system with sensing coils 123

and 4 and a common excitation pole

Examples of torque sensors

Four-branch type torque sensor

heads Pole structures realized

by commercial multi-pole

ferrites 14 and 18 min in

diameter (diameter of sensor

h e a d 1 7 a n d 2 4 m m

respectively) respectively)

Principle of Ring Torductor torque transducer

(a b) Physical structure (c) evolution of the

shaft surface under the transducer poles A and BRing torductor for measuring

torque on ship propeller shafts

(shaft diameter ca 500 mm)

(Courtesy ASEA Brown

Boveri AG)

Principal designs of coaxial torque sensors

Schematic diagram of data processing

electronics of a torque sensor

Extensometer (a) Construction of strain sensing element using

amorphous ribbon wound core (b) configuration of lumped

windings

∆E effect of an amorphous FeNi-based

alloy (Fe40 Ni38 Mo4 B18) Hs saturation

field

Magnetically tunable delay line

Torque Sensors using Amorphous wire

Sixtus tonk효과(large Barkhausen효과)

Hysteresis loops of a Wiegand wire for different reset fields

Curie 온도 및Hopkinson효과

Relation between normalised

saturation polarisation and

normalised Curie temperature

Permeability of a Mn-Zn ferrite as

a function of temperature and field

strength

Conclusions

1) Magnetic sensor 는 자동차 공장자동화 항공우주 및 군사용으로많이 사용되고 있다

2) 새로운 소재개발은 자기센서의 성능개발에 직접적인 영향을 준다2) 새로운 소재개발은 자기센서의 성능개발에 직접적인 영향을 준다

3) 센서의 개발을 위해서는 다양한 전공지식이 요구된다

(물리학 재료공학 기계공학 전자공학)

4) 센서분야가 고부가가치를 창출하는 부품사업이다

5) 핵심부품을 생산하는 중소기업의 item으로도 적절하다

00

05

10

B (T)

800

1000

1200

1400

1600

Magnetostriction (ppm)

-100 -50 0 50 100

-10

-05

00

B (T)

H (kAm)

2 MPa

4 MPa

6 MPa

8 MPa

10 MPa

12 MPa

-100 -50 0 50 100

-200

0

200

400

600

Magnetostriction (ppm)

H (kAm)

2 MPa

4 MPa

6 MPa

8 MPa

10 MPa

12 MPa

600

700

800

900

1000

-4 -3 -2 -1 0 1 2 3 4

0

10

20

30

40

50

60

Displacement (m

icro meter)

I (A)

FIELD

9 kAm

12 kAm

16 kAm

20 kAm

24 kAm

38 kAm

-50 -40 -30 -20 -10 0 10 20 30 40 50

-100

0

100

200

300

400

500

L (PPM)

H (kAm)

9 kAm

12 kAm

16 kAm

20 kAm

24 kAm

38 kAm

Magnetostrictive displacement sensor

Hysteresis loops under

tensile stress σ

(a) Crystalline 68 NiFe

λs = +25 10-6

(b) crystalline pure Ni λs

= -35 10-6

Villari Effect ( Inverse of Joule Effect)

= -35 10-6

(c) amorphous Co-based

alloy

λs = -35 10-6

ϕσλ 2sin2

3sdotsdot= smeE

γ

Permeability depending on the stress

σλmicromicro

1

3

2

Y

J

so

s

r =

γ

Calculated magnetization curves under stress

Variation of magnetization curve by an applied

tensile force (Co-based amorphous alloy)

Alloy Requirement

Materials for magnetoelastic sensors

Why amorphous magnetic materials are important

Stress-strain curves of several materials

Coercivity and hardness of several materials

Principles of magnetoelastic sensors

Non-contact torque sensor

Principle of cross torductor torque

sensor and flux pattern of sensor

poles on the surface of a shaft

a) without and b)with torsional load

Equivalent magnetic circuit of

cross type torque sensor

Helices of principal tensile and compressive stress on the surface of

a shaft subjected to torsion [32] Correlated changes of permeability

are detected by four-branch yoke system with sensing coils 123

and 4 and a common excitation pole

Examples of torque sensors

Four-branch type torque sensor

heads Pole structures realized

by commercial multi-pole

ferrites 14 and 18 min in

diameter (diameter of sensor

h e a d 1 7 a n d 2 4 m m

respectively) respectively)

Principle of Ring Torductor torque transducer

(a b) Physical structure (c) evolution of the

shaft surface under the transducer poles A and BRing torductor for measuring

torque on ship propeller shafts

(shaft diameter ca 500 mm)

(Courtesy ASEA Brown

Boveri AG)

Principal designs of coaxial torque sensors

Schematic diagram of data processing

electronics of a torque sensor

Extensometer (a) Construction of strain sensing element using

amorphous ribbon wound core (b) configuration of lumped

windings

∆E effect of an amorphous FeNi-based

alloy (Fe40 Ni38 Mo4 B18) Hs saturation

field

Magnetically tunable delay line

Torque Sensors using Amorphous wire

Sixtus tonk효과(large Barkhausen효과)

Hysteresis loops of a Wiegand wire for different reset fields

Curie 온도 및Hopkinson효과

Relation between normalised

saturation polarisation and

normalised Curie temperature

Permeability of a Mn-Zn ferrite as

a function of temperature and field

strength

Conclusions

1) Magnetic sensor 는 자동차 공장자동화 항공우주 및 군사용으로많이 사용되고 있다

2) 새로운 소재개발은 자기센서의 성능개발에 직접적인 영향을 준다2) 새로운 소재개발은 자기센서의 성능개발에 직접적인 영향을 준다

3) 센서의 개발을 위해서는 다양한 전공지식이 요구된다

(물리학 재료공학 기계공학 전자공학)

4) 센서분야가 고부가가치를 창출하는 부품사업이다

5) 핵심부품을 생산하는 중소기업의 item으로도 적절하다

600

700

800

900

1000

-4 -3 -2 -1 0 1 2 3 4

0

10

20

30

40

50

60

Displacement (m

icro meter)

I (A)

FIELD

9 kAm

12 kAm

16 kAm

20 kAm

24 kAm

38 kAm

-50 -40 -30 -20 -10 0 10 20 30 40 50

-100

0

100

200

300

400

500

L (PPM)

H (kAm)

9 kAm

12 kAm

16 kAm

20 kAm

24 kAm

38 kAm

Magnetostrictive displacement sensor

Hysteresis loops under

tensile stress σ

(a) Crystalline 68 NiFe

λs = +25 10-6

(b) crystalline pure Ni λs

= -35 10-6

Villari Effect ( Inverse of Joule Effect)

= -35 10-6

(c) amorphous Co-based

alloy

λs = -35 10-6

ϕσλ 2sin2

3sdotsdot= smeE

γ

Permeability depending on the stress

σλmicromicro

1

3

2

Y

J

so

s

r =

γ

Calculated magnetization curves under stress

Variation of magnetization curve by an applied

tensile force (Co-based amorphous alloy)

Alloy Requirement

Materials for magnetoelastic sensors

Why amorphous magnetic materials are important

Stress-strain curves of several materials

Coercivity and hardness of several materials

Principles of magnetoelastic sensors

Non-contact torque sensor

Principle of cross torductor torque

sensor and flux pattern of sensor

poles on the surface of a shaft

a) without and b)with torsional load

Equivalent magnetic circuit of

cross type torque sensor

Helices of principal tensile and compressive stress on the surface of

a shaft subjected to torsion [32] Correlated changes of permeability

are detected by four-branch yoke system with sensing coils 123

and 4 and a common excitation pole

Examples of torque sensors

Four-branch type torque sensor

heads Pole structures realized

by commercial multi-pole

ferrites 14 and 18 min in

diameter (diameter of sensor

h e a d 1 7 a n d 2 4 m m

respectively) respectively)

Principle of Ring Torductor torque transducer

(a b) Physical structure (c) evolution of the

shaft surface under the transducer poles A and BRing torductor for measuring

torque on ship propeller shafts

(shaft diameter ca 500 mm)

(Courtesy ASEA Brown

Boveri AG)

Principal designs of coaxial torque sensors

Schematic diagram of data processing

electronics of a torque sensor

Extensometer (a) Construction of strain sensing element using

amorphous ribbon wound core (b) configuration of lumped

windings

∆E effect of an amorphous FeNi-based

alloy (Fe40 Ni38 Mo4 B18) Hs saturation

field

Magnetically tunable delay line

Torque Sensors using Amorphous wire

Sixtus tonk효과(large Barkhausen효과)

Hysteresis loops of a Wiegand wire for different reset fields

Curie 온도 및Hopkinson효과

Relation between normalised

saturation polarisation and

normalised Curie temperature

Permeability of a Mn-Zn ferrite as

a function of temperature and field

strength

Conclusions

1) Magnetic sensor 는 자동차 공장자동화 항공우주 및 군사용으로많이 사용되고 있다

2) 새로운 소재개발은 자기센서의 성능개발에 직접적인 영향을 준다2) 새로운 소재개발은 자기센서의 성능개발에 직접적인 영향을 준다

3) 센서의 개발을 위해서는 다양한 전공지식이 요구된다

(물리학 재료공학 기계공학 전자공학)

4) 센서분야가 고부가가치를 창출하는 부품사업이다

5) 핵심부품을 생산하는 중소기업의 item으로도 적절하다

Magnetostrictive displacement sensor

Hysteresis loops under

tensile stress σ

(a) Crystalline 68 NiFe

λs = +25 10-6

(b) crystalline pure Ni λs

= -35 10-6

Villari Effect ( Inverse of Joule Effect)

= -35 10-6

(c) amorphous Co-based

alloy

λs = -35 10-6

ϕσλ 2sin2

3sdotsdot= smeE

γ

Permeability depending on the stress

σλmicromicro

1

3

2

Y

J

so

s

r =

γ

Calculated magnetization curves under stress

Variation of magnetization curve by an applied

tensile force (Co-based amorphous alloy)

Alloy Requirement

Materials for magnetoelastic sensors

Why amorphous magnetic materials are important

Stress-strain curves of several materials

Coercivity and hardness of several materials

Principles of magnetoelastic sensors

Non-contact torque sensor

Principle of cross torductor torque

sensor and flux pattern of sensor

poles on the surface of a shaft

a) without and b)with torsional load

Equivalent magnetic circuit of

cross type torque sensor

Helices of principal tensile and compressive stress on the surface of

a shaft subjected to torsion [32] Correlated changes of permeability

are detected by four-branch yoke system with sensing coils 123

and 4 and a common excitation pole

Examples of torque sensors

Four-branch type torque sensor

heads Pole structures realized

by commercial multi-pole

ferrites 14 and 18 min in

diameter (diameter of sensor

h e a d 1 7 a n d 2 4 m m

respectively) respectively)

Principle of Ring Torductor torque transducer

(a b) Physical structure (c) evolution of the

shaft surface under the transducer poles A and BRing torductor for measuring

torque on ship propeller shafts

(shaft diameter ca 500 mm)

(Courtesy ASEA Brown

Boveri AG)

Principal designs of coaxial torque sensors

Schematic diagram of data processing

electronics of a torque sensor

Extensometer (a) Construction of strain sensing element using

amorphous ribbon wound core (b) configuration of lumped

windings

∆E effect of an amorphous FeNi-based

alloy (Fe40 Ni38 Mo4 B18) Hs saturation

field

Magnetically tunable delay line

Torque Sensors using Amorphous wire

Sixtus tonk효과(large Barkhausen효과)

Hysteresis loops of a Wiegand wire for different reset fields

Curie 온도 및Hopkinson효과

Relation between normalised

saturation polarisation and

normalised Curie temperature

Permeability of a Mn-Zn ferrite as

a function of temperature and field

strength

Conclusions

1) Magnetic sensor 는 자동차 공장자동화 항공우주 및 군사용으로많이 사용되고 있다

2) 새로운 소재개발은 자기센서의 성능개발에 직접적인 영향을 준다2) 새로운 소재개발은 자기센서의 성능개발에 직접적인 영향을 준다

3) 센서의 개발을 위해서는 다양한 전공지식이 요구된다

(물리학 재료공학 기계공학 전자공학)

4) 센서분야가 고부가가치를 창출하는 부품사업이다

5) 핵심부품을 생산하는 중소기업의 item으로도 적절하다

Hysteresis loops under

tensile stress σ

(a) Crystalline 68 NiFe

λs = +25 10-6

(b) crystalline pure Ni λs

= -35 10-6

Villari Effect ( Inverse of Joule Effect)

= -35 10-6

(c) amorphous Co-based

alloy

λs = -35 10-6

ϕσλ 2sin2

3sdotsdot= smeE

γ

Permeability depending on the stress

σλmicromicro

1

3

2

Y

J

so

s

r =

γ

Calculated magnetization curves under stress

Variation of magnetization curve by an applied

tensile force (Co-based amorphous alloy)

Alloy Requirement

Materials for magnetoelastic sensors

Why amorphous magnetic materials are important

Stress-strain curves of several materials

Coercivity and hardness of several materials

Principles of magnetoelastic sensors

Non-contact torque sensor

Principle of cross torductor torque

sensor and flux pattern of sensor

poles on the surface of a shaft

a) without and b)with torsional load

Equivalent magnetic circuit of

cross type torque sensor

Helices of principal tensile and compressive stress on the surface of

a shaft subjected to torsion [32] Correlated changes of permeability

are detected by four-branch yoke system with sensing coils 123

and 4 and a common excitation pole

Examples of torque sensors

Four-branch type torque sensor

heads Pole structures realized

by commercial multi-pole

ferrites 14 and 18 min in

diameter (diameter of sensor

h e a d 1 7 a n d 2 4 m m

respectively) respectively)

Principle of Ring Torductor torque transducer

(a b) Physical structure (c) evolution of the

shaft surface under the transducer poles A and BRing torductor for measuring

torque on ship propeller shafts

(shaft diameter ca 500 mm)

(Courtesy ASEA Brown

Boveri AG)

Principal designs of coaxial torque sensors

Schematic diagram of data processing

electronics of a torque sensor

Extensometer (a) Construction of strain sensing element using

amorphous ribbon wound core (b) configuration of lumped

windings

∆E effect of an amorphous FeNi-based

alloy (Fe40 Ni38 Mo4 B18) Hs saturation

field

Magnetically tunable delay line

Torque Sensors using Amorphous wire

Sixtus tonk효과(large Barkhausen효과)

Hysteresis loops of a Wiegand wire for different reset fields

Curie 온도 및Hopkinson효과

Relation between normalised

saturation polarisation and

normalised Curie temperature

Permeability of a Mn-Zn ferrite as

a function of temperature and field

strength

Conclusions

1) Magnetic sensor 는 자동차 공장자동화 항공우주 및 군사용으로많이 사용되고 있다

2) 새로운 소재개발은 자기센서의 성능개발에 직접적인 영향을 준다2) 새로운 소재개발은 자기센서의 성능개발에 직접적인 영향을 준다

3) 센서의 개발을 위해서는 다양한 전공지식이 요구된다

(물리학 재료공학 기계공학 전자공학)

4) 센서분야가 고부가가치를 창출하는 부품사업이다

5) 핵심부품을 생산하는 중소기업의 item으로도 적절하다

γ

Permeability depending on the stress

σλmicromicro

1

3

2

Y

J

so

s

r =

γ

Calculated magnetization curves under stress

Variation of magnetization curve by an applied

tensile force (Co-based amorphous alloy)

Alloy Requirement

Materials for magnetoelastic sensors

Why amorphous magnetic materials are important

Stress-strain curves of several materials

Coercivity and hardness of several materials

Principles of magnetoelastic sensors

Non-contact torque sensor

Principle of cross torductor torque

sensor and flux pattern of sensor

poles on the surface of a shaft

a) without and b)with torsional load

Equivalent magnetic circuit of

cross type torque sensor

Helices of principal tensile and compressive stress on the surface of

a shaft subjected to torsion [32] Correlated changes of permeability

are detected by four-branch yoke system with sensing coils 123

and 4 and a common excitation pole

Examples of torque sensors

Four-branch type torque sensor

heads Pole structures realized

by commercial multi-pole

ferrites 14 and 18 min in

diameter (diameter of sensor

h e a d 1 7 a n d 2 4 m m

respectively) respectively)

Principle of Ring Torductor torque transducer

(a b) Physical structure (c) evolution of the

shaft surface under the transducer poles A and BRing torductor for measuring

torque on ship propeller shafts

(shaft diameter ca 500 mm)

(Courtesy ASEA Brown

Boveri AG)

Principal designs of coaxial torque sensors

Schematic diagram of data processing

electronics of a torque sensor

Extensometer (a) Construction of strain sensing element using

amorphous ribbon wound core (b) configuration of lumped

windings

∆E effect of an amorphous FeNi-based

alloy (Fe40 Ni38 Mo4 B18) Hs saturation

field

Magnetically tunable delay line

Torque Sensors using Amorphous wire

Sixtus tonk효과(large Barkhausen효과)

Hysteresis loops of a Wiegand wire for different reset fields

Curie 온도 및Hopkinson효과

Relation between normalised

saturation polarisation and

normalised Curie temperature

Permeability of a Mn-Zn ferrite as

a function of temperature and field

strength

Conclusions

1) Magnetic sensor 는 자동차 공장자동화 항공우주 및 군사용으로많이 사용되고 있다

2) 새로운 소재개발은 자기센서의 성능개발에 직접적인 영향을 준다2) 새로운 소재개발은 자기센서의 성능개발에 직접적인 영향을 준다

3) 센서의 개발을 위해서는 다양한 전공지식이 요구된다

(물리학 재료공학 기계공학 전자공학)

4) 센서분야가 고부가가치를 창출하는 부품사업이다

5) 핵심부품을 생산하는 중소기업의 item으로도 적절하다

Variation of magnetization curve by an applied

tensile force (Co-based amorphous alloy)

Alloy Requirement

Materials for magnetoelastic sensors

Why amorphous magnetic materials are important

Stress-strain curves of several materials

Coercivity and hardness of several materials

Principles of magnetoelastic sensors

Non-contact torque sensor

Principle of cross torductor torque

sensor and flux pattern of sensor

poles on the surface of a shaft

a) without and b)with torsional load

Equivalent magnetic circuit of

cross type torque sensor

Helices of principal tensile and compressive stress on the surface of

a shaft subjected to torsion [32] Correlated changes of permeability

are detected by four-branch yoke system with sensing coils 123

and 4 and a common excitation pole

Examples of torque sensors

Four-branch type torque sensor

heads Pole structures realized

by commercial multi-pole

ferrites 14 and 18 min in

diameter (diameter of sensor

h e a d 1 7 a n d 2 4 m m

respectively) respectively)

Principle of Ring Torductor torque transducer

(a b) Physical structure (c) evolution of the

shaft surface under the transducer poles A and BRing torductor for measuring

torque on ship propeller shafts

(shaft diameter ca 500 mm)

(Courtesy ASEA Brown

Boveri AG)

Principal designs of coaxial torque sensors

Schematic diagram of data processing

electronics of a torque sensor

Extensometer (a) Construction of strain sensing element using

amorphous ribbon wound core (b) configuration of lumped

windings

∆E effect of an amorphous FeNi-based

alloy (Fe40 Ni38 Mo4 B18) Hs saturation

field

Magnetically tunable delay line

Torque Sensors using Amorphous wire

Sixtus tonk효과(large Barkhausen효과)

Hysteresis loops of a Wiegand wire for different reset fields

Curie 온도 및Hopkinson효과

Relation between normalised

saturation polarisation and

normalised Curie temperature

Permeability of a Mn-Zn ferrite as

a function of temperature and field

strength

Conclusions

1) Magnetic sensor 는 자동차 공장자동화 항공우주 및 군사용으로많이 사용되고 있다

2) 새로운 소재개발은 자기센서의 성능개발에 직접적인 영향을 준다2) 새로운 소재개발은 자기센서의 성능개발에 직접적인 영향을 준다

3) 센서의 개발을 위해서는 다양한 전공지식이 요구된다

(물리학 재료공학 기계공학 전자공학)

4) 센서분야가 고부가가치를 창출하는 부품사업이다

5) 핵심부품을 생산하는 중소기업의 item으로도 적절하다

Alloy Requirement

Materials for magnetoelastic sensors

Why amorphous magnetic materials are important

Stress-strain curves of several materials

Coercivity and hardness of several materials

Principles of magnetoelastic sensors

Non-contact torque sensor

Principle of cross torductor torque

sensor and flux pattern of sensor

poles on the surface of a shaft

a) without and b)with torsional load

Equivalent magnetic circuit of

cross type torque sensor

Helices of principal tensile and compressive stress on the surface of

a shaft subjected to torsion [32] Correlated changes of permeability

are detected by four-branch yoke system with sensing coils 123

and 4 and a common excitation pole

Examples of torque sensors

Four-branch type torque sensor

heads Pole structures realized

by commercial multi-pole

ferrites 14 and 18 min in

diameter (diameter of sensor

h e a d 1 7 a n d 2 4 m m

respectively) respectively)

Principle of Ring Torductor torque transducer

(a b) Physical structure (c) evolution of the

shaft surface under the transducer poles A and BRing torductor for measuring

torque on ship propeller shafts

(shaft diameter ca 500 mm)

(Courtesy ASEA Brown

Boveri AG)

Principal designs of coaxial torque sensors

Schematic diagram of data processing

electronics of a torque sensor

Extensometer (a) Construction of strain sensing element using

amorphous ribbon wound core (b) configuration of lumped

windings

∆E effect of an amorphous FeNi-based

alloy (Fe40 Ni38 Mo4 B18) Hs saturation

field

Magnetically tunable delay line

Torque Sensors using Amorphous wire

Sixtus tonk효과(large Barkhausen효과)

Hysteresis loops of a Wiegand wire for different reset fields

Curie 온도 및Hopkinson효과

Relation between normalised

saturation polarisation and

normalised Curie temperature

Permeability of a Mn-Zn ferrite as

a function of temperature and field

strength

Conclusions

1) Magnetic sensor 는 자동차 공장자동화 항공우주 및 군사용으로많이 사용되고 있다

2) 새로운 소재개발은 자기센서의 성능개발에 직접적인 영향을 준다2) 새로운 소재개발은 자기센서의 성능개발에 직접적인 영향을 준다

3) 센서의 개발을 위해서는 다양한 전공지식이 요구된다

(물리학 재료공학 기계공학 전자공학)

4) 센서분야가 고부가가치를 창출하는 부품사업이다

5) 핵심부품을 생산하는 중소기업의 item으로도 적절하다

Why amorphous magnetic materials are important

Stress-strain curves of several materials

Coercivity and hardness of several materials

Principles of magnetoelastic sensors

Non-contact torque sensor

Principle of cross torductor torque

sensor and flux pattern of sensor

poles on the surface of a shaft

a) without and b)with torsional load

Equivalent magnetic circuit of

cross type torque sensor

Helices of principal tensile and compressive stress on the surface of

a shaft subjected to torsion [32] Correlated changes of permeability

are detected by four-branch yoke system with sensing coils 123

and 4 and a common excitation pole

Examples of torque sensors

Four-branch type torque sensor

heads Pole structures realized

by commercial multi-pole

ferrites 14 and 18 min in

diameter (diameter of sensor

h e a d 1 7 a n d 2 4 m m

respectively) respectively)

Principle of Ring Torductor torque transducer

(a b) Physical structure (c) evolution of the

shaft surface under the transducer poles A and BRing torductor for measuring

torque on ship propeller shafts

(shaft diameter ca 500 mm)

(Courtesy ASEA Brown

Boveri AG)

Principal designs of coaxial torque sensors

Schematic diagram of data processing

electronics of a torque sensor

Extensometer (a) Construction of strain sensing element using

amorphous ribbon wound core (b) configuration of lumped

windings

∆E effect of an amorphous FeNi-based

alloy (Fe40 Ni38 Mo4 B18) Hs saturation

field

Magnetically tunable delay line

Torque Sensors using Amorphous wire

Sixtus tonk효과(large Barkhausen효과)

Hysteresis loops of a Wiegand wire for different reset fields

Curie 온도 및Hopkinson효과

Relation between normalised

saturation polarisation and

normalised Curie temperature

Permeability of a Mn-Zn ferrite as

a function of temperature and field

strength

Conclusions

1) Magnetic sensor 는 자동차 공장자동화 항공우주 및 군사용으로많이 사용되고 있다

2) 새로운 소재개발은 자기센서의 성능개발에 직접적인 영향을 준다2) 새로운 소재개발은 자기센서의 성능개발에 직접적인 영향을 준다

3) 센서의 개발을 위해서는 다양한 전공지식이 요구된다

(물리학 재료공학 기계공학 전자공학)

4) 센서분야가 고부가가치를 창출하는 부품사업이다

5) 핵심부품을 생산하는 중소기업의 item으로도 적절하다

Principles of magnetoelastic sensors

Non-contact torque sensor

Principle of cross torductor torque

sensor and flux pattern of sensor

poles on the surface of a shaft

a) without and b)with torsional load

Equivalent magnetic circuit of

cross type torque sensor

Helices of principal tensile and compressive stress on the surface of

a shaft subjected to torsion [32] Correlated changes of permeability

are detected by four-branch yoke system with sensing coils 123

and 4 and a common excitation pole

Examples of torque sensors

Four-branch type torque sensor

heads Pole structures realized

by commercial multi-pole

ferrites 14 and 18 min in

diameter (diameter of sensor

h e a d 1 7 a n d 2 4 m m

respectively) respectively)

Principle of Ring Torductor torque transducer

(a b) Physical structure (c) evolution of the

shaft surface under the transducer poles A and BRing torductor for measuring

torque on ship propeller shafts

(shaft diameter ca 500 mm)

(Courtesy ASEA Brown

Boveri AG)

Principal designs of coaxial torque sensors

Schematic diagram of data processing

electronics of a torque sensor

Extensometer (a) Construction of strain sensing element using

amorphous ribbon wound core (b) configuration of lumped

windings

∆E effect of an amorphous FeNi-based

alloy (Fe40 Ni38 Mo4 B18) Hs saturation

field

Magnetically tunable delay line

Torque Sensors using Amorphous wire

Sixtus tonk효과(large Barkhausen효과)

Hysteresis loops of a Wiegand wire for different reset fields

Curie 온도 및Hopkinson효과

Relation between normalised

saturation polarisation and

normalised Curie temperature

Permeability of a Mn-Zn ferrite as

a function of temperature and field

strength

Conclusions

1) Magnetic sensor 는 자동차 공장자동화 항공우주 및 군사용으로많이 사용되고 있다

2) 새로운 소재개발은 자기센서의 성능개발에 직접적인 영향을 준다2) 새로운 소재개발은 자기센서의 성능개발에 직접적인 영향을 준다

3) 센서의 개발을 위해서는 다양한 전공지식이 요구된다

(물리학 재료공학 기계공학 전자공학)

4) 센서분야가 고부가가치를 창출하는 부품사업이다

5) 핵심부품을 생산하는 중소기업의 item으로도 적절하다

Non-contact torque sensor

Principle of cross torductor torque

sensor and flux pattern of sensor

poles on the surface of a shaft

a) without and b)with torsional load

Equivalent magnetic circuit of

cross type torque sensor

Helices of principal tensile and compressive stress on the surface of

a shaft subjected to torsion [32] Correlated changes of permeability

are detected by four-branch yoke system with sensing coils 123

and 4 and a common excitation pole

Examples of torque sensors

Four-branch type torque sensor

heads Pole structures realized

by commercial multi-pole

ferrites 14 and 18 min in

diameter (diameter of sensor

h e a d 1 7 a n d 2 4 m m

respectively) respectively)

Principle of Ring Torductor torque transducer

(a b) Physical structure (c) evolution of the

shaft surface under the transducer poles A and BRing torductor for measuring

torque on ship propeller shafts

(shaft diameter ca 500 mm)

(Courtesy ASEA Brown

Boveri AG)

Principal designs of coaxial torque sensors

Schematic diagram of data processing

electronics of a torque sensor

Extensometer (a) Construction of strain sensing element using

amorphous ribbon wound core (b) configuration of lumped

windings

∆E effect of an amorphous FeNi-based

alloy (Fe40 Ni38 Mo4 B18) Hs saturation

field

Magnetically tunable delay line

Torque Sensors using Amorphous wire

Sixtus tonk효과(large Barkhausen효과)

Hysteresis loops of a Wiegand wire for different reset fields

Curie 온도 및Hopkinson효과

Relation between normalised

saturation polarisation and

normalised Curie temperature

Permeability of a Mn-Zn ferrite as

a function of temperature and field

strength

Conclusions

1) Magnetic sensor 는 자동차 공장자동화 항공우주 및 군사용으로많이 사용되고 있다

2) 새로운 소재개발은 자기센서의 성능개발에 직접적인 영향을 준다2) 새로운 소재개발은 자기센서의 성능개발에 직접적인 영향을 준다

3) 센서의 개발을 위해서는 다양한 전공지식이 요구된다

(물리학 재료공학 기계공학 전자공학)

4) 센서분야가 고부가가치를 창출하는 부품사업이다

5) 핵심부품을 생산하는 중소기업의 item으로도 적절하다

Helices of principal tensile and compressive stress on the surface of

a shaft subjected to torsion [32] Correlated changes of permeability

are detected by four-branch yoke system with sensing coils 123

and 4 and a common excitation pole

Examples of torque sensors

Four-branch type torque sensor

heads Pole structures realized

by commercial multi-pole

ferrites 14 and 18 min in

diameter (diameter of sensor

h e a d 1 7 a n d 2 4 m m

respectively) respectively)

Principle of Ring Torductor torque transducer

(a b) Physical structure (c) evolution of the

shaft surface under the transducer poles A and BRing torductor for measuring

torque on ship propeller shafts

(shaft diameter ca 500 mm)

(Courtesy ASEA Brown

Boveri AG)

Principal designs of coaxial torque sensors

Schematic diagram of data processing

electronics of a torque sensor

Extensometer (a) Construction of strain sensing element using

amorphous ribbon wound core (b) configuration of lumped

windings

∆E effect of an amorphous FeNi-based

alloy (Fe40 Ni38 Mo4 B18) Hs saturation

field

Magnetically tunable delay line

Torque Sensors using Amorphous wire

Sixtus tonk효과(large Barkhausen효과)

Hysteresis loops of a Wiegand wire for different reset fields

Curie 온도 및Hopkinson효과

Relation between normalised

saturation polarisation and

normalised Curie temperature

Permeability of a Mn-Zn ferrite as

a function of temperature and field

strength

Conclusions

1) Magnetic sensor 는 자동차 공장자동화 항공우주 및 군사용으로많이 사용되고 있다

2) 새로운 소재개발은 자기센서의 성능개발에 직접적인 영향을 준다2) 새로운 소재개발은 자기센서의 성능개발에 직접적인 영향을 준다

3) 센서의 개발을 위해서는 다양한 전공지식이 요구된다

(물리학 재료공학 기계공학 전자공학)

4) 센서분야가 고부가가치를 창출하는 부품사업이다

5) 핵심부품을 생산하는 중소기업의 item으로도 적절하다

Examples of torque sensors

Four-branch type torque sensor

heads Pole structures realized

by commercial multi-pole

ferrites 14 and 18 min in

diameter (diameter of sensor

h e a d 1 7 a n d 2 4 m m

respectively) respectively)

Principle of Ring Torductor torque transducer

(a b) Physical structure (c) evolution of the

shaft surface under the transducer poles A and BRing torductor for measuring

torque on ship propeller shafts

(shaft diameter ca 500 mm)

(Courtesy ASEA Brown

Boveri AG)

Principal designs of coaxial torque sensors

Schematic diagram of data processing

electronics of a torque sensor

Extensometer (a) Construction of strain sensing element using

amorphous ribbon wound core (b) configuration of lumped

windings

∆E effect of an amorphous FeNi-based

alloy (Fe40 Ni38 Mo4 B18) Hs saturation

field

Magnetically tunable delay line

Torque Sensors using Amorphous wire

Sixtus tonk효과(large Barkhausen효과)

Hysteresis loops of a Wiegand wire for different reset fields

Curie 온도 및Hopkinson효과

Relation between normalised

saturation polarisation and

normalised Curie temperature

Permeability of a Mn-Zn ferrite as

a function of temperature and field

strength

Conclusions

1) Magnetic sensor 는 자동차 공장자동화 항공우주 및 군사용으로많이 사용되고 있다

2) 새로운 소재개발은 자기센서의 성능개발에 직접적인 영향을 준다2) 새로운 소재개발은 자기센서의 성능개발에 직접적인 영향을 준다

3) 센서의 개발을 위해서는 다양한 전공지식이 요구된다

(물리학 재료공학 기계공학 전자공학)

4) 센서분야가 고부가가치를 창출하는 부품사업이다

5) 핵심부품을 생산하는 중소기업의 item으로도 적절하다

Principle of Ring Torductor torque transducer

(a b) Physical structure (c) evolution of the

shaft surface under the transducer poles A and BRing torductor for measuring

torque on ship propeller shafts

(shaft diameter ca 500 mm)

(Courtesy ASEA Brown

Boveri AG)

Principal designs of coaxial torque sensors

Schematic diagram of data processing

electronics of a torque sensor

Extensometer (a) Construction of strain sensing element using

amorphous ribbon wound core (b) configuration of lumped

windings

∆E effect of an amorphous FeNi-based

alloy (Fe40 Ni38 Mo4 B18) Hs saturation

field

Magnetically tunable delay line

Torque Sensors using Amorphous wire

Sixtus tonk효과(large Barkhausen효과)

Hysteresis loops of a Wiegand wire for different reset fields

Curie 온도 및Hopkinson효과

Relation between normalised

saturation polarisation and

normalised Curie temperature

Permeability of a Mn-Zn ferrite as

a function of temperature and field

strength

Conclusions

1) Magnetic sensor 는 자동차 공장자동화 항공우주 및 군사용으로많이 사용되고 있다

2) 새로운 소재개발은 자기센서의 성능개발에 직접적인 영향을 준다2) 새로운 소재개발은 자기센서의 성능개발에 직접적인 영향을 준다

3) 센서의 개발을 위해서는 다양한 전공지식이 요구된다

(물리학 재료공학 기계공학 전자공학)

4) 센서분야가 고부가가치를 창출하는 부품사업이다

5) 핵심부품을 생산하는 중소기업의 item으로도 적절하다

Principal designs of coaxial torque sensors

Schematic diagram of data processing

electronics of a torque sensor

Extensometer (a) Construction of strain sensing element using

amorphous ribbon wound core (b) configuration of lumped

windings

∆E effect of an amorphous FeNi-based

alloy (Fe40 Ni38 Mo4 B18) Hs saturation

field

Magnetically tunable delay line

Torque Sensors using Amorphous wire

Sixtus tonk효과(large Barkhausen효과)

Hysteresis loops of a Wiegand wire for different reset fields

Curie 온도 및Hopkinson효과

Relation between normalised

saturation polarisation and

normalised Curie temperature

Permeability of a Mn-Zn ferrite as

a function of temperature and field

strength

Conclusions

1) Magnetic sensor 는 자동차 공장자동화 항공우주 및 군사용으로많이 사용되고 있다

2) 새로운 소재개발은 자기센서의 성능개발에 직접적인 영향을 준다2) 새로운 소재개발은 자기센서의 성능개발에 직접적인 영향을 준다

3) 센서의 개발을 위해서는 다양한 전공지식이 요구된다

(물리학 재료공학 기계공학 전자공학)

4) 센서분야가 고부가가치를 창출하는 부품사업이다

5) 핵심부품을 생산하는 중소기업의 item으로도 적절하다

Schematic diagram of data processing

electronics of a torque sensor

Extensometer (a) Construction of strain sensing element using

amorphous ribbon wound core (b) configuration of lumped

windings

∆E effect of an amorphous FeNi-based

alloy (Fe40 Ni38 Mo4 B18) Hs saturation

field

Magnetically tunable delay line

Torque Sensors using Amorphous wire

Sixtus tonk효과(large Barkhausen효과)

Hysteresis loops of a Wiegand wire for different reset fields

Curie 온도 및Hopkinson효과

Relation between normalised

saturation polarisation and

normalised Curie temperature

Permeability of a Mn-Zn ferrite as

a function of temperature and field

strength

Conclusions

1) Magnetic sensor 는 자동차 공장자동화 항공우주 및 군사용으로많이 사용되고 있다

2) 새로운 소재개발은 자기센서의 성능개발에 직접적인 영향을 준다2) 새로운 소재개발은 자기센서의 성능개발에 직접적인 영향을 준다

3) 센서의 개발을 위해서는 다양한 전공지식이 요구된다

(물리학 재료공학 기계공학 전자공학)

4) 센서분야가 고부가가치를 창출하는 부품사업이다

5) 핵심부품을 생산하는 중소기업의 item으로도 적절하다

Extensometer (a) Construction of strain sensing element using

amorphous ribbon wound core (b) configuration of lumped

windings

∆E effect of an amorphous FeNi-based

alloy (Fe40 Ni38 Mo4 B18) Hs saturation

field

Magnetically tunable delay line

Torque Sensors using Amorphous wire

Sixtus tonk효과(large Barkhausen효과)

Hysteresis loops of a Wiegand wire for different reset fields

Curie 온도 및Hopkinson효과

Relation between normalised

saturation polarisation and

normalised Curie temperature

Permeability of a Mn-Zn ferrite as

a function of temperature and field

strength

Conclusions

1) Magnetic sensor 는 자동차 공장자동화 항공우주 및 군사용으로많이 사용되고 있다

2) 새로운 소재개발은 자기센서의 성능개발에 직접적인 영향을 준다2) 새로운 소재개발은 자기센서의 성능개발에 직접적인 영향을 준다

3) 센서의 개발을 위해서는 다양한 전공지식이 요구된다

(물리학 재료공학 기계공학 전자공학)

4) 센서분야가 고부가가치를 창출하는 부품사업이다

5) 핵심부품을 생산하는 중소기업의 item으로도 적절하다

∆E effect of an amorphous FeNi-based

alloy (Fe40 Ni38 Mo4 B18) Hs saturation

field

Magnetically tunable delay line

Torque Sensors using Amorphous wire

Sixtus tonk효과(large Barkhausen효과)

Hysteresis loops of a Wiegand wire for different reset fields

Curie 온도 및Hopkinson효과

Relation between normalised

saturation polarisation and

normalised Curie temperature

Permeability of a Mn-Zn ferrite as

a function of temperature and field

strength

Conclusions

1) Magnetic sensor 는 자동차 공장자동화 항공우주 및 군사용으로많이 사용되고 있다

2) 새로운 소재개발은 자기센서의 성능개발에 직접적인 영향을 준다2) 새로운 소재개발은 자기센서의 성능개발에 직접적인 영향을 준다

3) 센서의 개발을 위해서는 다양한 전공지식이 요구된다

(물리학 재료공학 기계공학 전자공학)

4) 센서분야가 고부가가치를 창출하는 부품사업이다

5) 핵심부품을 생산하는 중소기업의 item으로도 적절하다

Torque Sensors using Amorphous wire

Sixtus tonk효과(large Barkhausen효과)

Hysteresis loops of a Wiegand wire for different reset fields

Curie 온도 및Hopkinson효과

Relation between normalised

saturation polarisation and

normalised Curie temperature

Permeability of a Mn-Zn ferrite as

a function of temperature and field

strength

Conclusions

1) Magnetic sensor 는 자동차 공장자동화 항공우주 및 군사용으로많이 사용되고 있다

2) 새로운 소재개발은 자기센서의 성능개발에 직접적인 영향을 준다2) 새로운 소재개발은 자기센서의 성능개발에 직접적인 영향을 준다

3) 센서의 개발을 위해서는 다양한 전공지식이 요구된다

(물리학 재료공학 기계공학 전자공학)

4) 센서분야가 고부가가치를 창출하는 부품사업이다

5) 핵심부품을 생산하는 중소기업의 item으로도 적절하다

Sixtus tonk효과(large Barkhausen효과)

Hysteresis loops of a Wiegand wire for different reset fields

Curie 온도 및Hopkinson효과

Relation between normalised

saturation polarisation and

normalised Curie temperature

Permeability of a Mn-Zn ferrite as

a function of temperature and field

strength

Conclusions

1) Magnetic sensor 는 자동차 공장자동화 항공우주 및 군사용으로많이 사용되고 있다

2) 새로운 소재개발은 자기센서의 성능개발에 직접적인 영향을 준다2) 새로운 소재개발은 자기센서의 성능개발에 직접적인 영향을 준다

3) 센서의 개발을 위해서는 다양한 전공지식이 요구된다

(물리학 재료공학 기계공학 전자공학)

4) 센서분야가 고부가가치를 창출하는 부품사업이다

5) 핵심부품을 생산하는 중소기업의 item으로도 적절하다

Curie 온도 및Hopkinson효과

Relation between normalised

saturation polarisation and

normalised Curie temperature

Permeability of a Mn-Zn ferrite as

a function of temperature and field

strength

Conclusions

1) Magnetic sensor 는 자동차 공장자동화 항공우주 및 군사용으로많이 사용되고 있다

2) 새로운 소재개발은 자기센서의 성능개발에 직접적인 영향을 준다2) 새로운 소재개발은 자기센서의 성능개발에 직접적인 영향을 준다

3) 센서의 개발을 위해서는 다양한 전공지식이 요구된다

(물리학 재료공학 기계공학 전자공학)

4) 센서분야가 고부가가치를 창출하는 부품사업이다

5) 핵심부품을 생산하는 중소기업의 item으로도 적절하다

Conclusions

1) Magnetic sensor 는 자동차 공장자동화 항공우주 및 군사용으로많이 사용되고 있다

2) 새로운 소재개발은 자기센서의 성능개발에 직접적인 영향을 준다2) 새로운 소재개발은 자기센서의 성능개발에 직접적인 영향을 준다

3) 센서의 개발을 위해서는 다양한 전공지식이 요구된다

(물리학 재료공학 기계공학 전자공학)

4) 센서분야가 고부가가치를 창출하는 부품사업이다

5) 핵심부품을 생산하는 중소기업의 item으로도 적절하다