Inverter_Training SE.pdf

ＹＡＳＫＡＷＡ1

Training ManualTraining Manualfor Advanced Sales Stafffor Advanced Sales Staff

SubjectSubject Inverter BasicsInverter BasicsChapter 1Chapter 1Principle and Characteristics of Principle and Characteristics of Induction MotorsInduction MotorsChapter 2Chapter 2Inverter Principle and Inverter Principle and CharacteristicsCharacteristicsChapter 3Chapter 3Operation CharacteristicsOperation CharacteristicsChapter 4Chapter 4Inverter Drive Units SelectionInverter Drive Units Selection

Chapter 5Chapter 5Inverter Functions and AdvantagesInverter Functions and AdvantagesChapter 6Chapter 6Inverter Drives Precautions Inverter Drives Precautions Chapter 7Chapter 7Harmonics, Noise & Surge VoltageHarmonics, Noise & Surge VoltageChapter 8Chapter 8Maintenance and Inspection Maintenance and Inspection Chapter 9Chapter 9Reference Reference


Training for Advanced Sales StaffTraining for Advanced Sales Staff

Inverter BasicsInverter Basics


Market of General purpose InvertersMarket of General purpose Inverters

IntroductionIntroduction


(General-purpose inverters up to 75 kW)Marketing of 2,200,000 units worth \73,000,000,000

Inverter Market TrendInverter Market Trend

\ (Hundred million)

Unit(×10000）

Actual Record Estimation*Actual record is in accordance with “Statistics Investigation on Production Trends” of Ministry of Economy, Trade and Industry.

The data of 2003 is an estimation made by Japan Electrical Manufacturers’ Association (JEMA).

(Hundredmillion)

Transition of Market Scale Tens of thousands


TotalTotal1.813million1.813million

FujiFuji24.3%24.3%

MitsubishiMitsubishi30.5%30.5%

ToshibaToshiba9.5%9.5%

HitachiHitachi5.9%5.9%

OthersOthers6.0%6.0%

TotalTotal2,342M US$2,342M US$

YaskawaYaskawa12.8%12.8%

FujiFuji9.6%9.6%

MitsubishiMitsubishi9.8%9.8%

OthersOthers25.8%25.8%

WorldWorld

YaskawaYaskawa23.7%23.7%

ABBABB10.0%10.0%

Rockwell Rockwell 12.1%12.1%

SiemensSiemens7.9%7.9%

※Data estimated by Sales Promotion Section

ToshibaToshiba--SchneiderSchneider7.2%7.2%

C.TC.T4.8%4.8%

Inverter Market Shares Inverter Market Shares (FY 2001 )(FY 2001 )

JapanJapan

unitsunits

※This share represents No. of unitsproduced in Japan.


VS-610

VS-610B

VS-616T

Thyristor inverter (current type)

Thyristor inverter (current type)

PWM transistor inverter (analog)

Varispeed G7

Varispeed F7

VS mini V7

VS mini J7

World’s First

World’s First

77thth GenerationGeneration

＊ 3-level

World’s First

Year of 1968

1974

1980

VS-616HⅡ PWM transistor inverter (digital)1984

VS-616GⅡ, GⅡLN PWM transistor inverter (IGBT, low-noise type)1987

3rd Generation

VS-616G3, etc.PWM transistor inverter

1989

5th Generation

VS-616G5, etc.PWM transistor inverter

1995

1969

World’s First

VS-616G, H PWM transistor inverter (analog)

Year of 2000

2000

1998

1998

Year of 2000 to 2003

History of Yaskawa GeneralHistory of Yaskawa General--purpose Inverterspurpose Inverters


Global Sales and Production NetworkGlobal Sales and Production Network

Yaskawa Inverter BusinessYaskawa Inverter Business

● : Sale office□ : Production facility

Taian Technology SDN (YTM)

Yaskawa HongKong (YHK)

YE America Inc. (YEA)

YE Do Brazil Co. LTDA (YEB)

YE Taiwan Corp. (YTW)

YE Korea Corp. (YEK)

Inverter Plant (V)

Yaskawa Electric (YEC)

YE UK Ltd. (YGB)

YE Singapore Pte. (YSP)

YE Shaghai Co Ltd Shanghai Yaskawa-Tongji M&E Co. Ltd (SSC)

YE Europe Ltd. (YEG)

YE Shaghai Co Ltd (SYD)


Typical Industrial ApplicationsTypical Industrial ApplicationsMachine Names

Industrial Field Other Machines

Iron, steel making ○ ○ ○ ○ ○ Rolling mill, Steel plate processorWire drawing ○ ○ ○ ○ ○ Winder, Rolling millChemical ○ ○ ○ ○ ○ ○ ○ ○ Film processorTextile ○ ○ ○ ○ ○ ○ Spinning machine, WeaverAutomobile ○ ○ ○ ○ PressMachine tool ○ Lathe, Surface grinder, Machining center, PressFood ○ ○ ○ Noodle maker, Confectionery maker, PackerPaper, Pulp ○ ○ ○ ○ Paper machine, Paper processor, PrinterCement ○ ○ ○ ○ －

Loading, Feeding ○ ○ ○ Automatic warehousePlant, Building ○ ○ ○ ○ ○ Elevator, Water-supply tower

Primary industry ○ ○ ○ ○Shed, Henhouse, Processing M/c for Tea,Processing M/c for Sea Weed

Pum

p

Fan,

Blo

wer

Cra

neFe

edin

g ca

rrie

r

Con

veyo

r

Ext

rude

r

Mix

erC

entri

fuga

l se

para

tor

Com

pres

sor

Air

cond

ition

er


FunctionsFunctions

Functions Subject to Variable Speed Drives

Needs for Production Facility Application, Facility

Reduction of drive power by speed changes ○ ○ ○

Power reduction mode at run (light load, no load) ○ ○ ○ ○

Improvement of machine stop position accuracy ○ ○ ○ ○ ○ ○

Improvement of line speed control accuracy ○ ○ ○ ○ ○

Automation of flow rate control ○ ○ ○

Improvement of productivity by increasing line speed ○ ○ ○ ○ ○ ○ ○ ○

FMC of facility ○ ○ ○ ○ ○ ○ ○ ○

Optimum operation by no-step speed changes ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○

Optimum operation for product quality ○ ○ ○ ○ ○ ○ ○

Optimum operation for product processing ○ ○ ○ ○

Matching of speed between units in line ○ ○ ○ ○ ○ ○

Optimization of reaction time ○ ○ ○ ○ ○ ○

Smooth start, accel/decel, stop ○ ○ ○ ○ ○ ○ ○ ○

Extension of facility lifetime by speed reduction at no load ○ ○ ○ ○ ○ ○

Reduction of maintenance by using no brushes ○ ○ ○ ○ ○ ○

Reduction of maintenance by using no contacts ○ ○ ○ ○ ○ ○

Installation in explosionproof area ○ ○ ○ ○ ○ ○ ○

Noise reduction of facility ○ ○ ○

Machine downsizing by increasing speed ○ ○ ○

Facility downsizing compared to mechanical speed changes ○ ○ ○ ○

Ene

rgy

savi

ng

Impr

ovem

ent o

f pr

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Upg

radi

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f fac

ility

Faci

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dow

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Cor

resp

onde

nce

to

envi

ronm

ent

Fan,

Pum

p

Com

pres

sor

Mix

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entri

fuga

l se

para

tor

Ext

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r

Con

veyo

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Feed

er

Trav

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g ca

rrier

Ele

vato

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Grin

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San

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Pre

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Prin

ter

Impr

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f m

aint

aina

bilit

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(%)

低速運転時の運転性能

0 10 20 30 40 50 60 70 80 90 100

品質・性能

振　動

保護機能

騒　音

耐久性・寿命

ブレーキ特性

寸法・質量

始動トルク

高調波対策

(Item)

User’s EvaluationUser’s EvaluationSatisfaction Level

Investigated in 1987Investigated in 1999

[by Japan Electrical Manufacturer’s Association (JEMA)]

Quality, Performance

Vibration

Protective functions

Noise

Durability, lifetime

Brake characteristics

Size, weight

Starting torque

Operation characteristics at low-speed operation

Prevention from harmonics


Chapter 1Chapter 1Principle and Characteristics Principle and Characteristics

of Induction Motorsof Induction Motors


Flange-mounted type

Induction MotorsInduction Motors

Foot-mounted type


Motors

Motors for motive power

Motors for dynamic response

DC motors (series, shunt, compound)

AC motors

Induction motors(Squirrel-cage, wound rotor type)

Synchronous motors(Magnet type, field winding type)

Motors with eddy-current coupling(VS-MOTOR)

ServomotorsDC servomotors

AC servomotors(SM, IM types)

Types of MotorsTypes of Motors


① ④ ③ ⑧

⑤

⑦

⑥⑨⑧⑩

⑦

②

⑪

⑫

① Stator frame ⑦ Bearing② Output shaft ⑧ Bracket③ Stator coil ⑨ Internal fan④ Stator iron core ⑩ External fan⑤ Rotor End ring ⑪ Terminal box⑥ Rotor iron core ⑫ Center height (motor frame No.)

(a) Configuration of Squirrel-cage Induction Motor (Example of Totally-enclosed Externally-cooled Type)

(b) Squirrel-cage Rotor (Excluding Iron Core)

Rotor End Ring

Secondary Conductor

ConfigurationConfiguration


Force ( F ) Magnetic field (Flux density B (wb/m2) )

Current ( I (A) )

Force (F)Magnetic field (Flux density B (wb/m2) )

Current ( I (A) )

Length of conductor ( (m) )

Fleming’s LeftFleming’s Left--hand Rulehand Rule

¯sin´BIF ã [N]

θ

´

´


ARAGO’s Disc(Disc rotates following magnet rotation.)

Induction Effect of Rotating Magnetic Field

N

S

Permanent Magnet

Rotary Shaft

Iron Disc

PrinciplePrinciple


Current Direction

Direction of Magnetic Flux

Right Screw

A. Right hand screw Rule

Current Direction

B. Coil Current and Magnetic Flux Directions

Direction of Magnetic Flux

Beginning of Coil Winding

End of Coil Winding

Magnetic Flux Generated by CurrentMagnetic Flux Generated by CurrentDirection of Mag. flux from front to back of paper face

：

Direction of Mag. flux from back to front of paper face

：


Three-phase motors use three-phase alternating current to create a rotating magnetic field.

U

V

W

U

Phase U Phase V Phase W

VWU’

V’ W’

0 π ωｔ2π

Principle of Rotating Magnetic Field (2 Pole)Principle of Rotating Magnetic Field (2 Pole)

U, V, W : START of CoilU’,V’,W’: END of Coil

1 Cycle

3-phase AC (Current)

Direction of Magnetic

Field

(a) Three-phase Alternating Current (Power Supply) and Magnetic Field Direction

Induction Motor


Rotating Magnetic Field of a 4Rotating Magnetic Field of a 4--pole Motorpole Motor

(a) Coil Arrangement

Phase U Phase V Phase W

(b) Three-phase Alternating Current

N

N

S

S1

1


P o w e r S u pp ly F re que ncy (f)

N o . o f P o le s

(P )

N o . o f C o ils pe r

P h as e 5 0 H z 6 0 H z

2 1 3 000 3 600

4 2 1 500 1 800

6 3 1 000 1 200

8 4 750 900

S N

S N

N S

2p 4p

8p6p(a) Synchronous Speed (min-1)

(b) Number of Poles (p)

Number of Poles and Synchronous SpeedNumber of Poles and Synchronous Speed

S N

S N

N S

S NN

N

NS

S

S


The above equation can be changed into the following one.

Therefore:

■ Synchronous SpeedThe speed at which the magnetic field rotates is called synchronous speed (NS), which depends on the number of magnetic poles p , that depends on the configuration of the motor stator winding, and power supply frequency f .

■ Rotating SpeedRotor speed N ( min-1 ) is a little slower than synchronous speed Ns . This amount is called

“slip”, which is defined as follows:

S

S

NNN

Só

ã

ø ÷SSNN óã 1

ø ÷N fp

Sã ó120 1

pfN S

120ã NS : Synchronous speed ( min-1 )

f : Power supply frequency (Hz)( min-1 )

( min-1 )

Ns : Characteristic value dependingon motor specifications

s : Value varying on the load size

Induction Motor SpeedsInduction Motor Speeds


360018000[With 4 poles at 60 Hz ( min-1 )] - 1800

CharacteristicsCharacteristics

Torque

Rated Current

Stalling Torque

Rated Torque

Slip (Rating)

Motoring Area

Rated Speed

( PLU GGING )

No-load Current

Current (%)

Starting Current

Starting Torque

(Induction Generator)Regenerative Braking AreaReverse Phase Braking Area

Ns


Slot Form and Torque Characteristics of Induction MotorsSlot Form and Torque Characteristics of Induction Motors

Normal Squirrel-cage Type

Speed

Special Squirrel-cage Type Class 1

Special Squirrel-cage Type Class 2

Low Starting Torque Type

High Resistance Squirrel-cage Type

High Starting Torque Type

Aluminum die-castCopperBrassHigh-resistance alloy die-cast

Torq

ue

Speed

SpeedSpeed

Speed

Torq

ue

Torq

ueTo

rque

Torq

ue

Torq

ueSpeedStandard

Particular


（ｍｉｎ-1）

Control MethodControl Method

Load Torque

The intersection of the motor generating torque and the load torque becomes the operation speed.

To change the induction motor speed

Changing p(Pole change motor)

Changing s(Primary voltage control)

Changing s(Secondary resistance control)

Changing f

Number of Poles Large

Secondary Resistance Large

Voltage Small Frequency Small

(Primary frequency controlinverter drives)


Number of poles : 4 / 8（８Ｐ）（４Ｐ）

Example of Pole Change MotorExample of Pole Change Motor

(Example at 60 Hz)

８P ４P

Load Torque

N900 1800(min-1)

[For Low Speed]

[For High Speed]

[For Low Speed]

Pole Change Motor

Low Speed High Speed

1THR

2THR

0


ASR

Nfb

NrefPhase Shifter

Speed Reference

Unit

－＋

TG

Induction Motor

3-phase PowerSupply

Thyristor Type Primary Voltage Thyristor Type Primary Voltage Control CircuitControl Circuit

T ∝ V2

Load Torque

1800(min-1)

Voltage

Large

0

Speed DetectionGenerator

Example with 4 Poles at 60 Hz

PS


(a) Conceptual Diagram

(b) Symbol

(Slip Ring)

Secondary Resistor

R2’

Secondary Resistor

R2’

Wound Rotor Induction Motor Wound Rotor Induction Motor Secondary Resistor ControlSecondary Resistor Control

(Example with 4 Poles at 60 Hz)

1800(min-1)

(Stalling torque constant:Proportional Transition)

Load Torque

Large

Secondary Resistance Small

3-phase PowerSupply

3-phase PowerSupply

0


－

＋

Speed Reference

Thyristor Exciter

Power Supply

Speed DetectionGenerator

EddyEddy--current Coupling Motorcurrent Coupling Motor

(Example with 4 Poles at 60Hz)

1800(min-1)

Load Torque

Small

LargeExciting Current

Induction Motor Characteristics

Phase Shifter

Speed Deviation Amplifier

3-phase Power Supply

Drum

Load Machine

Induction Motor

Spider

Slip Ring

Exciting Current

0


* “BODY” is added in front of the protection symbol for any configuration without terminal box.

Type Configuration Operational Environment

Protection Symbol

(Representative Example)

Protection Type

Provided with ventilation openings in the housing. Theseopenings protect against round bars of 12 mm diameter or more.

・Ordinary environment (indoor) BODY

JP 20

Dripproof Type

The open-type with water dripping within 15 degrees verticallydoes not enter the motor interior directly or along the motorsurface.

・Ordinary environment・Under special ambient temperature・Exposed to water splashes

JP 12

Dripproof Protection

TypeSatisfies the conditions of both protection type and dripproof type. JP 22

Dripproof Dripproof Protection TypeProtection Type


Type Configuration Operational EnvironmentProtection

Symbol (Representative

Example)

Totally-enclosed Type

The housing is enclosed so that the outer air does not enter the motor interior.

・Ordinary environment (indoor)・Under special temperature・Under high temperature・Use in tropical area・ Exposed to excessive amount of dripping water or dust

BODYJP 44

Totally-enclosed, Fan-cooled Type

In addition to the totally-enclosed configuration, the housing surface is cooled by the fan mounted on the rotary axis.

JP 44

TotallyTotally--enclosed Fanenclosed Fan--cooled Typecooled Type


Type Configuration Operational EnvironmentProtection

Symbol (Representative

Example)

Outdoor TypeDurable for outdoor use.(Totally-enclosed type or totally-enclosed fan-cooled type)

・Ordinary environment (indoor)・Under special temperature・Under high temperature・Use in tropical area・ Exposed to excessive amount of water or dust

JPW 44

Totally-enclosed, Fan-

cooled Type

Can operate properly in a place exposed to corrosive acid, alkali or any other hazardous gases. (Totally-enclosed type or totally-enclosed fan-cooled type)

JPC 44

Outdoor TypeOutdoor Type Anticorrosion TypeAnticorrosion Type


Type Configuration Operational Environment

Protection Symbol

(Representative

Example)

Explosionproof Type (Increased Safety,

Pressure Proof, Internal Pressure)

Durable for outdoor use.(Totally-enclosed type or totally-enclosed fan-cooled type)

・Exposed to explosive gases

JPE 44

Dustproof, Explosionproof Type

Can operate properly in a place exposed to corrosive acid, alkali or any other hazardous gases. (Totally-enclosed or totally-enclosed fan-cooled type)

・Exposed to dust JPE 44

Explosionproof TypeExplosionproof Type


2. Applied Modification2. Applied Modification・Geared motors Output shaft torque increased

・Brake motorsQuick brakeAG brake motors

・Explosionproof motorsIncreased safety explosionproof motorsExplosionproof motors

Types of Inverter MotorsTypes of Inverter Motors

Fan Cover External FanExternal Fan (-K)

Pulse Generator (-M)

1. Inverter Drive Motors1. Inverter Drive Motors

FEQ-X, FEFFEK-I FEK-IK FEK-IKM

(With electric fan) (With electric fan and PG)

① Totally-enclosed

Model ： EEK-IM(With PG)

② Totally-enclosedFan-cooled Type

③ Totally-enclosedFan-cooled Type

④ Totally-enclosed Fan-cooled Type


The following shows the relation between the magnetic flux, voltage and frequency.

■ ExampleWhen speed is reduced to the half (60 Hz to 30 Hz), according to the above equation, set the inverter output voltage and output frequency so that the magnetic flux will be constant.

ttanCons)Hz(30)V(100

)Hz(60)V(200

fV

===

200

100

0 30 60Frequency (Hz)

In actual operation, voltage at low frequency must be increased by 150% to 200% in order to compensate for voltage drop in the motor.

Motor Characteristics at Inverter DrivesMotor Characteristics at Inverter Drives

Voltage (V)

Magnetic Flux ∝ Voltage VFrequency f

= Constant


The following shows the equation of motor rated torque.

■ ExampleIn case of a motor of 7.5 kW, 4 poles, rated speed 1740 min-1

Rated torque TM ＝ 974 × Motor rated output P (kW)Rated speed N (min-1) (kgf･m)

Rated torque TM ＝ 974 × 7.51740 (kgf･m)＝ 4.19

Rated torque TM ＝Motor rated output P (W)

Rated speed N (min-1) (N･m)602π ×

Rated torque TM ＝7.5×103

1740(N･m)＝ 41.260

2π ×

Motor Rated TorqueMotor Rated Torque


■ When load torque variesWhen load torque variesAs the load torque becomes greater, the motor speed decreases (or slip becomes greater).

At this time, the greater the load torque the greater the motor current.

■ When the motor applied voltage variesWhen the motor applied voltage variesThe motor generating torque is in proportion to the square of voltage.As the voltage becomes smaller, the speed decreases (or slip becomes greater).

Voltage Fluctuation and Speed Changes

Load Fluctuation and Speed Changes

Motor Speed VariationMotor Speed VariationOutput Torque

Speed

Load Large

Load Small

Speed

Voltage Large

Load Constant

Torq

ue

Voltage Small

Torq

ue


Inverter output voltage does not exceed power supply voltage.

Therefore, output voltage becomes constant in the range exceeding frequency 50 Hz or 60 Hz (base frequency).

The following equation shows the relation between motor voltage (V), frequency (f) and torque.

If

VKTorque T ××= K ： Constant

Ｉ： Current

Since only frequency is changed, torque is reduced in inverse proportion to frequency if the motor current value is the same as shown in the above equation.

This area is called “constant output area”.

Operations Exceeding 50Hz or 60HzOperations Exceeding 50Hz or 60Hz


Chapter 2Chapter 2Inverter Principle and CharacteristicsInverter Principle and Characteristics


Rectifier CircuitConverter Section

DC IntermediateCircuit

Smoothing Circuit Section

Invert ConversionCircuit

（Inverter Section）

Commercial Power

AC Power

Variable Frequency/Variable Voltage AC

Control Circuit Section

M

Motor

（VVVF）

Inverter ConfigurationInverter Configuration

AC Power


＋

－

0

Current wave

R

S4

S3S1

S2

DC Power Supply

Ｒ S1 S4 ON S1 S4 ON

S2 S3 ON

＋

－＋

－

How to Make AC

＋

－

ON ON

ON

SwitchesS1, S4

S2, S3

Ed

Principle of SinglePrinciple of Single--phase Inverterphase Inverter

+Ed

-Ed


S1

S4

DC Power Supply

S3

S6

S5

S2

U Motor

WV

＋

－Ed

Basic Circuit of 3Basic Circuit of 3--phase Inverterphase Inverter

+Ed

-Ed


IM

Motor

3-phase AC

EdDC Power Supply

＋

－

Basic Circuit of Transistor InverterBasic Circuit of Transistor Inverter

+Ed


Name Diode Thyristor GTO

(Gate Tum Off Thyristor)

Bipolar Power Transistor

IGBT (Insulated Gate Bipolar

Tr.)

Power MOS FET (Power Metal Oxide

Semiconductor. Field Effect Tr.)

Sym

bol

Cha

ract

eris

tics

Volta

ge, C

urre

nt

Wav

efor

m

Feat

ures

, A

pplic

atio

n General high-voltage, large-current rectifier circuits

High-voltage, large-current converter section Inverter section, chopper section attached with commutation circuit

High-voltage, large-current inverter section, chopper section

Medium voltage, medium current high-speed switching, inverter section

Medium voltage, medium current high-speed switching, inverter section

Low-voltage, small- current high-speed switching, inverter section

Main Semiconductor Power Elements Used for InvertersMain Semiconductor Power Elements Used for Inverters

Anode

CathodeGate

Collector

Base

Emitter

Drain

Gate

Source


Control Method Output Frequency Features

PAM Method (Pulse Amplitude Modulation)

・ Voltage control is

needed for the converter.

・ Motor current distortion is excessive, resulting in torque ripple.

PWM Method (Sinusoidal Wave Approximate) PWM: Pulse Width Modulation

When the above Output power frequency is 60 Hz, the number of pulses per cycle is 14. Therefore, carrier wave (carrier frequency) is obtained as 60×14 = 840 Hz. Since the actual inverter has this carrier frequency of 15 kHz, the number of pulses per cycle is 250 pulses (15000÷60).

・ Frequency and voltage

can be controlled only in the inverter section.

・ Smooth operation is possible at a low speed.

EdEd

(Ed: DC voltage)

Output Voltage Waveform

Ed

Ed

Average Output Voltage

VoltageVoltage--type Inverter Control Methodtype Inverter Control Method


~

P

N

C

MC

R

D3D2D1

D6D5D4

V

V

Ed

Vs

In-rush Current Suppression Resistor

Vs1.35≒　Vs　π

23dE ã

Converter SectionConverter Sectionand Inand In--rush Current Suppressionrush Current Suppression

（V）


Primary Frequency Control of Induction MotorsPrimary Frequency Control of Induction Motors

0-900-1800600 1800 3600

Load Torque

-30 Hz 0Hz(DC) 20 Hz 60 Hz

Speed（min-1）

<Example of 4 Poles>: In case of vector control(Torque –min-1 curve moves

horizontally.) : In case of V/f control(Torque is reduced at low speed.)

Torque


3-phase Power SupplyIM

Voltage/Current

Detection

N

0 t

Accel/decelInterrupt Signal

V

0f

PWM Signal

Generator

BaseDriver

VoltageReference

Accel/decel Adjuster V/f Setter

Frequency Reference

Speed (Frequency)Reference

Transistor Base Signal

Current DetectorMotor

InverterConverter

V/f Control PWM InverterV/f Control PWM Inverter


Rated Voltage

Voltage (V)

In Case of Variable Torque Load

In Case of Constant Torque Load

E/f Constant(Constant Magnetic Flux)

Compensation for Motor Primary Winding Voltage Drop

VoltageBias

Frequency f (Hz)Rated Frequency

V/f Constant

V/f control compensates for the voltage drop value of the motor primary winding for the constant E/f (magnetic flux).

Voltage / Frequency Characteristics Voltage / Frequency Characteristics in V/f Controlin V/f Control


úI2r1 l1

úEúVúI1

úIM

Mr2

12

óss

r

(b) Vector Diagram

ú ~I2ú ~I1

úI1

úI M

~¯¯

I2 I2’

I2

I1’

I1

IM

E

IM

EI1V

V : Motor terminal voltager1 : Primary winding resistanceE : Motor (internal) induced voltage r2 : Secondary winding resistanceI1 : Motor primary (stator) current l1 : Primary winding leak inductanceI2 : Motor secondary (rotor) currentM : Exciting inductanceIM : Exciting current (exciting current component of primary current) S : Slip

Equivalent Circuit and Vector DiagramEquivalent Circuit and Vector Diagram

V 1l

1r1I

1I

sr2

(a) Equivalent Circuit for Motor One Phase


tN－

＋I I I

II

M

M

12

22

1 2

ã õ

ã ó¯ tan

PWM Control÷

rM

2 fdt ×

×

×

Speed Reference

Torque Reference

Accel/decel Adjuster

Speed Feedback Signal

Speed ControllerCurrent Reference Calculator

Current Amplitude Reference

Torque Current Reference

Each Phase Current Reference

Multiplier

Instantaneous Current Control Circuit

Slip Frequency Reference

IIM

2

IM

Exciting Current Reference

Speed/Torque Control Switch

I 2

IM

Current Phase Reference

f s

fn

＋

＋

φ

3- (or 2-) phase Current Feedback Signal

PG (Speed Detector) (Pulse Generator)

Motor

Current Detector

Inverter

Converter

3-phase Power Supply

θ

I 2

M

Vector Control PWM InverterVector Control PWM Inverter


In Case of V/f Control In Case of Vector Control

V/f control suitable for the motor load characteristics is needed in order to obtain low-speed torque.

Constant calculation using the motor test report or combination by manufacturer is needed.

Varispeed G7Incorporates the auto-tuning program as standard so that no

complicated adjustment is needed.

● The following three methods are available for the auto-tuning. 1. Stop-type tuning only for line resistance2．Stop-type tuning3．Rotation-type tuning

Input the basic numerical values such as motor NP into the inverter so that the motor determines the motor constants required for the vector control by measurement and calculation. This function is called Auto-tuning.

AutoAuto--tuningtuning


Varispeed G7

Specifications V/f Control V/f Control with PG Feedback

Open-loop Vector Control

Flux Vector Control

Basic Control

Voltage/frequency control (open-loop)

Voltage/frequency control with speed

compensation

Current vector control without PG

Current vector control with PG

Speed Detector Not needed Needed

(pulse generator) Not needed Needed(pulse generator)

Option Card for Speed Detection Not needed Needed Not needed NeededSpeed Control

Range 1:40 1:40 1:200 1:1000

Starting Torque 150% at 3 Hz 150% at 3 Hz 150% at 3 Hz 150% at 0 min-1

Speed Control Accuracy ±2 to 3% ±0.03% ±0.2% ±0.02%

Torque Limit Disabled Disabled Enabled EnabledTorque Control Disabled Disabled Enabled Enabled

Typical Applications

● Multi-drives● Replacement for existing

motor of which motor constants are unknown

●Auto-tuning is enabled only for line resistance.

● Simplified feedback control

●Applications where pulse generator is attached on the machine shaft

●Any variable speed drives

● Simplified servo drives

● High-accuracy speed control

● Torque control

Features of Control ModeFeatures of Control Mode


Chapter 3 Chapter 3 Operation CharacteristicsOperation Characteristics


Induction Motor 4Induction Motor 4--quadrant Operationquadrant Operation(a) Speed Pattern

(b) Speed-Torque Characteristics

(FWD Run)

Speed

(REV Run)

Time

(REV Run) (FWD Run)

Speed

TorqueForward Phase Rotation

Reverse Phase Rotation (REV)

(FWD)


(a) Proper Acceleration Time (b) Short Acceleration Time

AccelerationAcceleration

Output Frequency f

Motor speed N

Overload capacity when inverter capacity is equal to motor capacity

Rated Current

Excessive Slip

Overload capacity when inverter capacity is increased

Rated Current

0

0 0

0


Inverter Output Frequency[Dotted line shows the set

accel. ratio.]

Motor Speed

Motor Current

Accel. time becomes longer automatically.

Peak current is limited to within the specified value.

Stall Prevention during AccelerationStall Prevention during Acceleration

t


Inverter Output Frequency[Dotted line shows the set decel. ratio.]

Motor Speed

DC Voltage

DC bus voltage is limited to within specified value.

Decel. time becomes longer automatically.

Stall Prevention during DecelerationStall Prevention during Deceleration

t


Inverter Output Frequency

Load

Stall Prevention during RunningStall Prevention during RunningTo avoid overloading by rapid fluid temperature in hydraulic machines. Avoid overloading by

decreasing output frequency.

t


DC Voltage


Motor Current

RUN Signal

Actual Stall Prevention FunctionActual Stall Prevention Function

Edc.

OV，OA


Set Decel. Time td

Slip

(Minus)

N Rapid decelerationSlip: Minus

f

fN,

t

NSlow decelerationSlip: Plus

Deceleration Time （td） Motor Operation Mode Slip

td＞Coasting to a stop time Motoring (Motoring area) Plus

td＜Coasting to a stop time Regeneration (power generation area) Minus

DecelerationDeceleration

0


t

DC Injection Braking Time

t

DC Current

N

N

t

DC Injection BrakingStarting Frequency

N, f

DC Current

DC Injection Braking Time

N

FF

F

(a) Frequency Deceleration(Example of DC Injection

Braking Before Stop)

(b) All-area DC Injection Braking (c) Coasting to a Stop

DC Injection BrakingDC Injection Braking

0 0 0

N, f N, f

Free Run


Inverter Load

Motor Output

Inverter OutputPower

Inverter Input Power

Power Supply

PowerPower SupplyMotor Loss

Motor Efficiency

IM

Inverter LossInverter Efficiency

Motor

● Inverter Efficiency ＝――――――― ＝ ―――――― Inverter Output Output

Inverter Input Output + Loss

● Total Efficiency ＝ ――――――― ＝ Inverter Efficiency × Motor Efficiency Motor Output

Inverter Input

● Motor Efficiency ＝ ――――――――――――― Motor Output

Motor Input (Inverter Output)

I/O Power Flow DiagramI/O Power Flow Diagram


(a) Commercial Power Operation (b) Inverter Operation

VI

φ

※ INV input current is a distortional wave current including harmonics. Unified effective current including harmonics is INV input current. Therefore, the power factor expressed by the above equation is not always equal to the value measured with general power factor meter.

Input Voltage / Current WaveformInput Voltage / Current Waveform

Power Factor = Active Power Active PowerActive Power + Reactive Power=

3Inverter Input Power

× Power Supply Voltage・ Inverter Input Current=

Apparent Power


*1. The connection cable between the reactor and the inverter must be 5 m or less, the shorter the better. The size must be equivalent to the power supply cable or larger.

*2. Models of 18.5 to 75 kW (200-V class) and 18.5 to 160 kW (400-V class) are incorporated with DC reactors. The power factor improvement is more than 93%.

*3. The inverter power supply power factor is normally approx. 60 to 90%, which differs depending on the power supply impedance.

■ Effect of power factor improvement: power supply factor 93 to 95% (at 100% load)*3

IM

NFBPower Supply

Inverter

1+ 2+

Be sure to remove the connected piece between terminals.

Wiring distance:*35 m or less.

Motor

UZDA-B

Power Factor Improvement Reactor*2

U X

Typical Connection of DC ReactorTypical Connection of DC Reactor

RST

UVW


Circuit Pattern Input Current Waveform Input Current Spectrum Harmonics Content

No countermeasures taken

Harmonics Order

88%

AC reactor inserted

38%

DC reactor inserted

33%

P

N

P

N

P

N

+

+

+

Typical Inverter Input Current WaveformTypical Inverter Input Current Waveformin Each Power Supply Method (1)in Each Power Supply Method (1)

1 5

1 5 7 11

1 5 7 11


Circuit Pattern Input Current Waveform Input Current Spectrum Harmonics Contents

12-phase rectification

Harmonics Order

12%

PWM control converter

3%

P

N

P

N

+

+

1

1

Typical Inverter Input Current WaveformTypical Inverter Input Current Waveformin Each Power Supply Method (2)in Each Power Supply Method (2)


Chapter 4Chapter 4Inverter Drive Units SelectionInverter Drive Units Selection


From General IndustrialFrom General Industrial--use to Consumer Equipmentuse to Consumer EquipmentGeneralGeneral--purpose Inverter Series purpose Inverter Series

Varispeed G7

Varispeed F7

VS mini V7

VS mini J7

High-graded Function Current Vector Control (0.4 to 300 kW)

General-purpose Vector Control (0.4 to 300 kW)

Small-size Voltage Vector Control (0.1 to 7.5 kW)

Super Small-size Contactor Type (0.1 to 3.7 kW)


Capacity (kW) Control Method Braking Method Speed Control

200V Class 400V Class V/f

VS mini J7 Single-phase: 0.1 to 1.53-phase: 0.1 to 3.7 3-phase: 0.2 to 3.7 ○ ― ― 1:40 ±2 to 3 ―

VS mini C Single-phase: 100 V 0.1 to0.75Single-phase,3-phase: 0.1 to 1.5 3-phase: 0.2 to 1.5 ○ ○ ― 1:40 ±2 to 3 ―

VS mini V7 Single-phase: 0.1 to 3.73-phase: 0.1 to 7.5 3-phase: 0.2 to 7.5

○○ ― 1:40

±2 to 3―

○ ±1

Varispeed F7 3-phase: 0.4 to 110 3-phase: 0.4 to 300○

○ ―1:40 ±2 to 3 ―

―○ 1:100 ±0.2

Varispeed G7 3-phase: 0.4 to 110 3-phase: 0.4 to 300○

○ ―1:40 ±2 to 3 ―

○ 1:200 ±0.2 ―○ 1:1000 ±0.02 ○

VS-616R3 3-phase: 3.7 to 37 3-phase: 7.5 to 75 ○ ― ○ 1:40 ±2 to 3 ―

VS-686SS5 3-phase: 0.4 to 753-phase: 0.4 to 160 ○

○ ―1:10 ±0.2 ―

3-phase: 0.4 to 300 ○ 1:500 ±0.02 ○O

pen-

loop

Flux

Vec

tor

Features of Each GeneralFeatures of Each General--purpose Inverter purpose Inverter

Pow

er

Reg

ener

atio

n

Res

isto

r D

isch

arge

Acc

urac

y (%

)

Con

trol

Ran

ge

Torq

ue C

ontr

ol


Model Features Output Range

VS-676H5 High-graded function type 200 V: 0.4 to 75 kW 400 V: 0.4 to 800 kW575 V: 300 to 1200 kW

VS-686HV5SHigh-voltage super energy

saving

3300 V: 132 to 1250 kW6600 V: 250 to 2500 kW

VS-686HV5 3300 V: 225 to 1800 kW6000 V: 450 to 3000 ｋW

VS-626M5/MR5Exclusive for machine tools

spindle(high accuracy)

200 V: 2.2 / 3.7 to 22 / 30 kW400 V: 3.7 / 5.5 to 37 / 45 kW

VS-626MC5 Exclusive for machine tools spindle (simplified type)

200 V: 2.2 / 3.7 to 11 / 15 kW

Sinusoidal wave PWMVS-656DC5

Harmonics: 0Power factor: 1

200 V: 15 to 75 kW400 V: 15 to 300 kW

VS-656RC5 Low cost type

200 V: 3.7 to 37 kW400 V: 3.7 to 75 kW

ExclusiveExclusive--use Inverter Seriesuse Inverter SeriesFo

r Sy

stem

Pow

er

Reg

ener

ativ

eC

onve

rter

For

Mac

hine

Tool

Spi

ndle

Pow

er

Reg

ener

ativ

eU

nit


Motor Type

Motor Output

Inverter Output

Inverter Model

Peripheral units, Options

Enclosure

インバータの機種選定

Check ItemWhat to Decide

Capacity SelectionCapacity Selection

Machine specifications

Operation method

Load type and characteristics

Inverter capacity selection

Inverter model selection

Motor selection

Peripheral units, options

Investment effect

Investment effect

Inverter selection

Final specifications


Load Characteristics Typical Load Speed –Torque Characteristics

・Load torque is constant for speed.・General friction loads

・Conveyor・Crane・Winch・Other friction loads

and gravity loads

・Load torque is constant regardless of speed.・Output power is in proportion to speed.

T = k T: torqueP = kN P: Output

k: Proportional constant

Loads of which load torque is decreased as the speed is reduced

・Fan・Blower・Pump・Other fluid loads

・Load torque is in proportion to the square of speed. ・Output is in proportion to the

cube of speed. T = kN2

P = kN3

Loads of which output becomes constant for the speed

・Constant tension force winder ofcenter drive・Spindle motors of

machine tools・Veneer rotary laths

・Output power required by the load is constant. ・Load torque is in inverse proportion to speed.

T = k/NP = k

・Loads of which load torque varies depending on the speed・Loads having the nature between the low output load and the constant torque load

・Speed –torque/output characteristics between the constant torque load and constant output load

Load Torque

Load Output

SpeedTorq

ue, O

utpu

t

Load Torque

Load OutputSpeedTo

rque

, Out

put

Typical Load Torque CharacteristicsTypical Load Torque Characteristics

0

1.0

1.0

2.0

Load Torque

Load Output

1.0

2.0

2.0Torq

ue, O

utpu

t To

rque

, Out

put

Red

uced

To

rque

Con

trol

To

rque

Load Output

Load Torque

Con

stan

t Po

wer

Red

uced

Po

wer

Speed

1.0

2.0


Motor may be overheated in a low-speed area.

Since the min-1 of the external fan becomes lower in a low-speed area, the cooling capability is deteriorated. Therefore, the motor may be overheated unless the load is reduced in a low-speed area.

Motor can operate properly even in a low-speed area.

The motor is designed for inverter drives, therefore, the temperature is within the specified value even if the motor is used at a low speed.

<Important><Important>The above characteristics show the torque that can be allowed at continuous operation. There is no difference in the torque that the motor can generate in a short time, such as at starting, between the standard motor and the constant torque motor.

Standard Motor Output Inverter Exclusive-use Motor Output

60

3 200.5

55

Difference between Inverter ExclusiveDifference between Inverter Exclusive--use Motor use Motor and Standard Motorand Standard Motor

Standard MotorStandard Motor Exclusive-use MotorExclusive-use Motor

Allo

wab

le L

oad

Torq

ue(%

)

Allo

wab

le L

oad

Torq

ue(%

)

Example:1:10 Const. Torque Motor


Relation between Frequency and Motor Speed Relation between Frequency and Motor Speed at Accel/Decelat Accel/Decel

During AccelNS ＞ N

During Constant SpeedNS ＞ N

During Decel(A): NS＜ N(B): NS ＞ N

ｆ・Ｎ

①＋

②＋

③＋ ④―――

④ ⑤―――

⑤

Inverter Frequency Motor Speed

During Decel(A) Small Load Torque, Short Decel Time (NS < N) (B) Large Load Torque, Long Decel Time (NS >

N)

＋① ＋②

＋③

＋④

＋⑤

0N

T

＋① ＋②

＋③

＋⑤

0N

T

＋④

＋⑤

’

’

’’

’


Load Torque

Accel TorqueDecel Torque

TL

Ta

Td

Ta

TL

Td＝ J・N9.55×td

Required Brake TorqueTB=（Td－TL）

Required Motor Torque（Ta＋TL）

Ta＝ J・N9.55×ta

TL＝ f・V２πN

１× （N・

m）η

The inverter regeneration capability is a key point. The regeneration capability depends on selection of the inverter output and braking unit type.

Operation Pattern and Calculation of Load TorqueOperation Pattern and Calculation of Load Torque

① Can start?Motor starting torque must be greater than load starting torque.

④Is motor temperature proper?Temperature rise must be within the specified value.

Time

② Can accelerate?Motor torque exceeding the torque requiredfor acceleration (Ta+TL) must be available.

The volume of the motor output torque is a key point.Torque depends on the motor output, inverter output, control method or boost amount.

Accel time Decel time

③Can decelerate?・Brake torque required for deceleration

must be available. ・Energy at deceleration can be consumed or

regenerated to the power supply.

２π609.55 ≒


Selection of Motor and InverterSelection of Motor and InverterCalculation of Motor and Inverter Capacities

η1

Nπ2Vf

TL •••

=

aa

t55.9NJ

T•

=

dd

t55.9NJ

T•

=

Load torque

Accel torque

Decel torque

(N・m)

① Calculate torque at accel, constant speed or decel.

②Select the motor that satisfies TL+Ta＜1.5TM (TM: motorrated torque, P:Motor Cap.(W)).

NP55.9

T M = (N・m)

③Select the inverter suitable for the motor output.In details, calculate the required apparent power (kVA) according to the motor efficiency and power factor to select the inverter output (kVA).

④Select the braking resistor (braking unit) according to Td－ TL .

Drum Gears IM PowerSupply

t

t

Td-TL

N2(N2 = 0)

Load

Tor

que

Spee

d N

W （kg）

ｆ（N）V（m/min）

INV

η : Machine EfficiencyJM : Moment of Inertia

(Rotating Part)μ: Friction Coefficient

Wμ8.9f •= 22

L )Nπ2

V(W

4GD

J ==(N)

ta tdtc

Total Inertia

(kg・m2)

LM JJJ +=

(N・m)

(N・m)

N1(N1 = N)

N1 = N (min-1)

TL+TaTL


(a) Motor Mode

(b) Generator (Regeneration) Mode

IMCommercial

Power Mechanical Energy

Power FlowPower Flowi

S ＞ 0(Motor power factor cosθ＞0)

*1 Discharge resistor = braking resistor *2 Monitors DC voltage and turns ON the transistor when DC voltage exceeds the specified level.

The inverter built-in braking transistor or braking unit is used.

IMCommercial

Power

Mechanical EnergyKinetic EnergyPotential Energy

Power Flow

(i =0）i

＋

*1R

*2(ON)

Thermal Energy

S ＜ 0(Motor power factor cosθ ＜ 0)

Power Flow and Regenerative BrakingPower Flow and Regenerative Braking


Actual Measured Braking FunctionActual Measured Braking Function

RUN Signal


DC Bus Bar Voltage

Braking Resistor Current

STOP RUN/STOP Reference

EDC

60Hz

0Hz


IM

(1) Power supply transformer

(2) Circuit breaker or(3) Leakage breaker

(4) Contactor

(6)Noise filter

(7) DC reactor

(8) Noise filter(11) Contactor

(13) Thermal relay

(9) Braking unit

(10) Braking resistor unit(12) Contactor for commercial

power backup

(5) AC reactor

Peripheral Devices and Their ConnectionsPeripheral Devices and Their Connections


No. Name Purpose and Selecting Points1 Power transformer ・Transformer capacity ＞ Inverter capacity × 1.5

2 Circuit breaker ・Breaks accidental current (shortcircuit current). ・Rated current ＞ inverter rated current ×1.5 → Described in the inverter catalog.

3 Leakage breaker

・Grounding protection・High frequency leak current protection for electric shock accident & leakage current fire.

1. Use a breaker provided with countermeasures for high frequency leakage current. 2. Increase sensitivity current.3. Decrease inverter carrier frequency.

4 Contactor・Since the inverter has the contactor function, any contactor is not needed except for special

cases.・When a braking resistor is used, insert a contactor to make thermal trip circuit.・Perform RUN/STOP at the inverter side and set the contactor to “Always ON” to use.

57

AC reactorDC reactor

・For high frequency current suppression and improvement of power factor・Install a reactor to protect the inverter when the power supply capacity is large.

68

Noise filter orZero-phase reactor ・Prevent radio noise generated by inverter section

910

Braking unitBraking resistor unit ・Used when an electrical brake is needed (when the required braking torque exceeds 20%).

1112

Contactor for commercial power backup

・Used for backup at inverter failure or when commercial power supply is used for normal operations.

13 Thermal relay ・Not needed when one motor is driven by one inverter. (Connected when more than two motors are used.)

How to Select Peripheral DevicesHow to Select Peripheral Devices


Chapter 5Chapter 5Inverter Functions and AdvantagesInverter Functions and Advantages


No. Advantage Technical Details Main Precautions

1

Can control speeds of the specified constant-speed type motors.

Number of revolutions changes when squirrel-cage-type motor terminal voltage and frequency are changed.

Since a standard motor has temperature rise that becomes greater at a low speed, torque must be reduced according to frequency.

2

Soft start/stop enabled. Accel/decel time can be set freely from a low speed.(0.01 to 6000 seconds).

Set proper accel/decel time after performing load operation.

3

Highly frequent start/stop enabled.

Little motor heat generation since smooth accel/decel is enabled with little current.

Motor or inverter capacity frame must be increased depending on the accel/decel capacity. Check the accel/decel time and load J.

4

FWD/REV run enabled without main circuit contactor.

Because of phase rotation changes by transistor, there are no moving parts like conventional contactors so that interlock operation can be assured.

When applying the inverter to an elevating unit, use a motor with a brake to hold mechanically for stand still.

Advantages of Inverter Applications (1)Advantages of Inverter Applications (1)

Cushion Start

t

f

FWD Run

REVRun

Cushion Stop

Inverter

RUN Command

FWD Run

REVRun

t

f



5

Can apply an electrical brake. Since mechanical energy is converted into electrical energy and absorbed in the inverter at decel, the motor can auto-matically provide braking force.DC current is applied to the motor around zero-speed so that it becomes dynamic braking, to completely stop the motor.

Braking force is approx. 20% when only the inverter is used. Attaching a braking resistor (optional) externally can increase the braking force.Pay attention to the capacity of the resistor.

6

Can control speeds of the motor under adverse atmosphere.

Since the inverter drives squirrel-cage motors, it can be used easily for explosionproof, waterproof, outdoor or special types of motors.

An explosionproof motor in combination with an inverter is subject to explosionproof certification.

7

High-speed rotation enabled. Commercial power supply can provide up to 3600 min-1 (2-pole at 60Hz) or 3000 min-

1 (2-pole, at 50Hz). A general-purpose inverter can increase frequency up to 400 Hz (12000 min-1) while a high-frequency inverter can increase it up to 3000 Hz (180000 min-1).

The speed of a general-purpose motor cannot be increased by simply increasing the frequency. (It can be applied without being changed if frequency is approx. 120 Hz.)Mechanical strength and dynamic balance must be examined. 60Hz 120Hz 400Hz

Electrical Braking


f

t

V

f



8

The speeds of more than one motor can be controlled by one inverter.

The inverter is a power supply unit to the motor, therefore, as many motors as the capacity allows can be connected.These motors do not have to be the same capacity.

The number of motor revolutions differs depending on each motor characteristics or load ratio even at the same frequency.(Among general-purpose motors, speed deviation of 2 to 3% can be considered.)Synchronous motors have the same number of revolutions.

9

Power supply capacity can be small when the motor is started up.

Large current (5 or 6 times larger than the motor rating) does not flow as with a commercial power supply start.Current can be limited to at most 100 to 150% by low-frequency start.

Transformer capacity (kVA)= 1.5 × inverter output capacity

10Number of revolutions becomes constant regardless of power supply frequency.

Output freq. can be set regardless of power supply freq. 50/60Hz.

Inverter


IM

IM

IM


Inverter Output Voltage

Inverter Output Current

Inverter Input Current

150%

150%100% Current

100% Current

100% Voltage (100% Speed)

t

Motor and Power Supply CurrentMotor and Power Supply Currentin Inverter Drivesin Inverter Drives

t

t0


Energy Saving for Energy Saving for General Industrial Machines & SystemsGeneral Industrial Machines & Systems

Min

imiz

e th

e En

ergy

Con

sum

ptio

ns

(1)Energy Saving for Mechanical Systems by Means of Variable Speed Drive of Motors

(2)High Efficiency Motors

(3)Change to High Efficiency Drive for Existing Variable Speed Drive

(4)Regeneration of Braking (Kinetic)Energy

(5)Others

A . Variable Torque LoadB . Constant Torque LoadC . Constant Power Load

A . High Efficiency Induction Motor B . IPM(Interior Permanent Magnet Motor)

A . Primary Voltage Control of Induction MotorB . Secondary Resistor Control of Wound Rotor Induction MotorC . VS-Motor (Eddy Current Coupling Motor)D . Variable Frequency Drive of Induction MotorE . Variable Frequency Drive of IPM

A . Regenerative ConverterB . Drive Regenerated Energy To Another Inv. Drive

A . ON-OFF Control for Mechanical SystemsB . Inverter Energy Saving (Voltage) Control Method


Applied Load Concept of Energy-saving

Fans Pumps Blowers (Any Variable Torque Load)

Replace with a more efficient motor. Reduce a redundancy of the facility for the actual loads. Abate the head loss at valves or dampers.

(2) (1) (1)

Extruders Conveyors, etc. (Any Constant Torque Load)

Change to more efficient drives. Replace the primary voltage control, secondary resistance control, eddy-current coupling (VS motors) with a more efficient control method(Frequency Control).

(3)

Cranes Elevators, etc.

Collect the regenerative energy at lowering by using the inverter power supply regenerative function.

(4)

Rewinders Collect the regenerative energy of the rewinders. Replace with a more efficient motor.

(4) (2)

General Machines Reduce the starting energy. (Use the inverter as a starter to stop the operations positively whenever the load ratio is low.)

(5)a

Optimum EnergyOptimum Energy--saving Plan for Facilitysaving Plan for Facility


AN

Hd

1.0

0 0.5 1.0 ( p.u.)Air volume (Q)

R

Hi

( p.u.)

Air Volume and Wind Pressure Air Volume and Wind Pressure Characteristics of FanCharacteristics of Fan

H＝1.03N２＋0.56NQ－0.59Q２

R＝Q２

Rated air volume: 250m3/secRated wind pressure: 433mmAqFan efficiency at rated air volume: 0.7Fan efficiency at 50% air volume: 0.6

Ad

Ai

R50

N50

Q50H0


Energy saving Effect in the Fan ApplicationEnergy saving Effect in the Fan Application① In the case of damper control

The wind pressure in 50% air volume is Hd = 1.03 + 0.56 × 0.5 - 0.59 × 0.52 = 1.16

The power becomesηm = 0.9 is the motor efficiency

② In the case of inverter controlThe wind pressure in 50% air volume is Hi = 0.52 = 0.25

The power becomesηi = 0.95 is the inverter efficiency

③ The electric-power saving quantityPS = PD－ Pi = 15.3kWOn the assumption of electric power unit price: \15/kWh and annual continuous running:

8000hours,We can save the electric charge as follows. 15.3 × 15 × 8000 = \ 1,836,000

19.0kW=433×250×0.9×0.6×6120

1.16×0.5=

6120QH

=Pmf

D ηη

3.7kW=433×250×0.95×0.9×0.7×6120

0.25×0.5=

6120QH

=Piimf ηηη


Flow Rate and Head Characteristics of PumpFlow Rate and Head Characteristics of Pump

Squeeze volume

Low speed

1.5

HB

1

Hi

0.5

0 0.5 1

Flow rate (P.U)

Hea

d (P

.U)

R50

R

NR0

N50


Energy saving Effect in the Pump ApplicationEnergy saving Effect in the Pump Application① In the case of valve control

The head in 50% flow rate is HB = 1.25 － 0.25 × 0.52 = 1.188

The power becomesηm = 0.9 is the motor efficiency

② In the case of inverter controlThe head in 50% flow rate is Hi = 0.7 ＋ 0.1 × 0.52 = 0.725

The power becomesηi = 0.95 is the inverter efficiency

③ The electric-power saving quantityPS = PB –Pi = 15.2kWOn the assumption of electric power unit price: \15/kWh and annual continuous running:

8000hours,We can save the electric charge as follows. 15. 2 × 15 × 8000 = \ 1,824,000

28.9kW=25×6×0.9×0.56×6.12

1.188×0.5=

6.12QH

=Pmp

B ηη

13.7kW=25×6×0.95×0.9×0.76×6.12

0.725×0.5=

6.12QH

=Piimp ηηη


Outline of Software Functions (1)Outline of Software Functions (1)Function Name Applications Purpose Description

Multi-step Speed Operation

Feeders, etc. Schedule operation at specified speed

By combining signals, operation is performed at frequency stored internally (up to 9-step speeds). Connection with the sequencer is easy; simplified positioning by using limit switch is also possible.

Accel/decel Changing Operation

Automatic panel feeders, etc.

Changing external signal of accel/decel time

Using an external signal can change the accel/decel rate. This function is effective when two motors are driven alternately by one inverter or when smooth accel/decel is needed only in the high-speed area.

S-curve Time Characteristics

feeders such as conveyors, carts, etc.

Prevention of start/stop shock

Smooth movement can be achieved by setting S-curve delay when accel/decel starts or finishes.

Frequency Upper/lower Limit Operation

PumpsBlowers

Limit of motor revolutions

Frequency reference upper/lower value, bias and gain can be set individually without adding any peripheral devices.

Specified Frequency Setting Prohibition (Frequency Jump Control)

General machines Prevention of machine system vibration

In order to prevent vibration of the machine system, the oscillation point is avoided automatically during constant-speed operation. This function can also be used for dead zone control.

DWELL Function Heavy-inertia loads such as centrifugal separators etc.

Smooth accel/decel of heavy-inertia loads

Prevents the motor from stalling by holding output frequency temporarily during accel/decel.

Speed Search Inertia load drives such as blowers, winders

Starting of coasting motor

Performs pull-in operation automatically into the set frequency withoutstopping the coasting motor. Motor speed detector is not needed.

Compensation for Momentary Power Loss

General machines Continuing operation at a momentary power loss

Restart the motor automatically after recovery from a momentary power loss by using the remaining control power supply to continue the motor operations.

Fault Retry Air-conditioning,etc.

Improvement of operation reliability

Resets the fault automatically after the inverter detects a fault and performs self-analysis and restarts the operation without stopping the motor. Up to 10 retry operations may be selected.



Carrier Frequency Setting General machines Noise reduction Sets the inverter carrier frequency to any arbitrary value to reducenoise oscillation from the motor and machine system. This function isalso effective for reducing noise.

Load Speed Display General machines Improvement of monitor function

Can display the motor speed (min-1), load machine rotating speed (min-1)or line speed (m/min).

Pulse Train Input General machines Improvement of operability

In addition to the function as frequency reference, PID aimed value and PID feedback value at PID control can be input as a pulse train.

Pulse Train Output General machines Improvement of monitoring performance

Frequency reference, output frequency, motor speed, output frequency after soft-start, PID feedback amount and PID input value can be output in pulses.

Stopping Method Selection

General machines Stopping method suitable for the machine characteristics

Selects deceleration to a stop, coasting to a stop or DC injection braking stop according to the braking torque or machine inertia.

3-wire Sequence General machines Simple configurationof control circuit

Operation is enabled using automatic-recovery-type pushbutton switch.

Frequency Hold Operation General machines Improvement of operability

Holds frequency increase/decrease temporarily during acceleration or deceleration.

UP/DOWN Operation General machines Improvement of operability

Speed setting is enabled remotely by ON/OFF operation.

Frequency Detection General machines Frequency detection to be used for interlock

Specifies the set value of output frequency, and outputs to the multi-function output terminal when frequency exceeds the range or becomes short.

Overtorque Detection and Undertorque Detection

・Machine tools・ Blowers, cutters,extruders

Machine protection, improvement of reliability for continuous operation

"Closed" when motor generating torque exceeds the overtorque detection level. Can be used as an interlock signal for machine protection such as cutting loss or overload detection of machine tools.



Stall Prevention General machines

Machine protection, improvement of reliability for continuous operation

Interrupts accel/decel when frequency reaches each set value during acceleration, deceleration or running, and continues operation when it becomes lower than the set value.

Electronic Overload Thermal Relay

General machines

Detection of motor overload

Set the motor rated current value and select the allowable load characteristics for each motor type, and the electronic overload thermal relay performs overload protection.

Torque Limit (Droop Characteristics Selection)

Pumps,blowers,extruders, etc.

・Machine protection・Improvement of reliability for continuous operation・Torque limit

Adjusts output frequency according to the load status when the motorgenerating torque reaches a certain level.Optimum for tip-less operation for pumps or blowers.

Energy-saving Control General machines

Automatic operation with maximum efficiency

Supplies sufficient voltage for the motor to reach maximum efficiency according to the load or rotating speed.

PID Control Pumps,air-conditioning,etc.

Automatic process control

Calculates the PID in the inverter and uses the result of the calculationas its own frequency reference to perform constant control of pressure,flow rate, wind amount, etc.

Droop Control ・Conveyors of distributed drives・Multi-drive motors

Proper distribution of load

Sets motor speed regulation to an arbitrary value.Making high-resistance characteristics distributes the loads of severalmotors properly.

Zero Servo Function Elevators, carts Zero-speed stop to lock the motor

Holds a motor in the locked status at zero speed whether external forceis applied in the forward or reverse direction.


■ Similar Machines・Air-conditioning fans for buildings・Fans for cooling tower・Dust collection blowers・Fans for boilers・Heat treating furnace blowers

Application for Dust Collection BlowersApplication for Dust Collection Blowers■Functions Available・Changing of commercial power supply

and inverter operations・Restart from coasting status・Energy-saving control mode at light load・Fault retry

Inverter

BlowerDust CollectorDamper

Motor MCMCMCB

MC


Application for Chemical Feeding PumpsApplication for Chemical Feeding Pumps

Inverter

Raw Water

PumpFlow Rate Detection

Adjuster

Motor

Chemical

Speed Reference

(4 to 20 mA)MCB

■ Similar Machines・Chemical feeding pumps・Cool/warm water circulation pumps ・Water supply/ discharge pumps ・Hydraulic pumps・Submersible pumps

■Functions Available・Energy-saving control mode at low speed ・PID control・4-20mA reference by instrumentation ・Minimum speed setting


Conveyor FollowConveyor Follow--up Operationup Operation

HopperFeeder

Conveyor

Geared Motor

Geared Motor

MCBMCB

PG Pulse Encoder

InverterInverter

Power SupplyMain

Speed Setting

Pulse Train Input

Power Supply

■ Similar Machines・Raw material supply conveyors ・Shuttle conveyors・Chain conveyors・Steel pipe feeding conveyors

■ Functions Available・Improvement of constant position stop accuracy ・Increasing the starting torque ・Smooth accel/decel・Changing accel/decel time・Simultaneous control of several motors by one inverter


Application for Chain ConveyorsApplication for Chain Conveyors

■Functions Available・Synchronous operation (linking operation) of 2 inverters・Proportional operation with other machines

Chain Conveyor for Painting Line

Drive Section

MCB

Power Supply

Power Supply

Power Supply

MCB

Geared Motor (Sub)

Adding

Position Controller

Phase Meter

Main Speed Setting

Soft Starter

Take-up

Drive Section

Take-up

Inverter

Synchronizer Transmitter

Synchronizer Receiver

Hunting Signal

Inverter

Geared Motor (Main)


(b) Lifting/Lowering Operations

To Incinerator

Hopper

Grab Trolley

No.1 Hopper No.2 Hopper No.3 Hopper No.4 Hopper

Pit

No.2 CraneNo.1 Crane(Stopping Position)

Pit

Garbage Carry-in

Crane Operation Room

Traveling Traverse

Garbage Carry-in

Crane Operation Room

Application for Garbage CranesApplication for Garbage Cranes

(a) Traverse/Traveling Operations

■ Similar Machines

・Cranes・Hoists・Stacker cranes・Elevators

■Functions Available・Prevention from slipping・Use of brake motors・Prevention from shock when a horizontal traveling motor starts・Changing operation of 2 horizontal traveling motors by one inverter・Energy-saving of existing winding-type motors


(Example where One Inverter Used Both for Traverse and Fork)

Application for Stacker CraneApplication for Stacker Crane(Automatic Warehouse)(Automatic Warehouse)

Upper Guide Roller

Traveling Unit

Carriage

Hoisting Unit

Fork

Suspension Chain

TrolleyMCB MC

MC

Incorporated Control Panel

MC

MC

MC

MC

For Fork

Brake

Brake

Brake

For Traveling

Elevating Motor

Inverter

Inverter


Example for Crane ExclusiveExample for Crane Exclusive--use use Software ( V/f Control )Software ( V/f Control )

IOUT : Inverter Output Frequency (Actual)FRF : Brake Release Frequency (Set)BF : Brake Operation Stand By Frequency (Set)BT : Brake Operation Delay Time (Set)IF : Brake Release Current (Set)

BDT : Brake Operation Delay Time (Actual)FHF : Brake Make Up Frequency (Set)HF : Slip Down Prevention Frequency (Set)HT : Slip Down Prevention Time (Set)

Closed

BF

FRF

Closed

Closed

Released

BT

BDT

IOUT＞IF

HT

BDT

HF

FTF

Speed Reference

(FWD) Run Command (F)

Output Frequency

Brake Release Command BR

Brake Release Check BX

Brake Operation


非常主幹

切入

ＭＳＭＳ

ＭＣ

ＦＬＴ

ＭＳ　主幹

ＭＳ　主回路コンダクタ

Ｆ　正転指令

Ｒ　逆転指令

Ｂ　ブレーキコンダクタ

ＢＢＸ　ブレーキ締め指令

ＢＸ　ブレーキ緩み確認

はツイストペアシールド線はシールド線(注)

Ｒ

Ｆ

ＢＲＸＦ

Ｒ

Ｂ

ＢＲ

ブレーキ自己保持

ブレーキ締め指令

逆転

停止

正確

MB MC

9 10

Ｂ

多機能アナログ出力

ＭＢ

ＩＭ

Ｒ

Ｓ

Ｔ

ＭＣ

R(L1)

S(L2)

T(L3)

Ｆ

Ｒ

外部異常

異常リセセット

ブレーキ緩み確認

多段速指令1

多段速指令3

外部ベースブロック*

*外部ベースブロック信号は、“閉”でベースブロック解除です。

ＢＸ

ＭＳ

2kΩ

2kΩ

2kΩ

P P

P

S1　正転運転／停止

S2　逆転運転／停止

S3

S4

S5

S6

S7

S8

S9

S10

S11

S12

SCシーケンスコモン(0V)端子とは絶縁されている

E(G)シールド被膜線接続端子

多機能端子

PR

A1

A2

A3

AC

0V

C4

P4

C3

P3

P2

P1

PC多機能ＰＨＣ出力48V　50mA以下

異常接点出力AC　250V　1A以下DC　 30V　1A以下

FLT

BRブレーキ緩め指令(閉でブレーキ緩め)AC　250V　1A以下DC　 30V　1A以下

MA

MB

MC

M1

M2

アナログモニタ 1

アナログモニタ 2

AF

AC

AM

(第3種接地)

U(T1)

V(T2)

W(T3)

Ｂ

Ｂ1

Ｂ21[ 2[

制動抵抗器ユニット(オプション)

Varispeed Ｇ７

未使用

加減速時間選択1

非常停止(a接点)

多段速指令2

Connection Diagram for CranesConnection Diagram for CranesEmergency Main Switch

MS Master Switch

MC Main Circuit Conductor

F FWD Run Command

R REV Run Command

B Brake Conductor

BBX Brake Applying Command

BX Brake Release Check

: Twisted pair-shielded cable

Braking Resistor Unit (Optional)

Varispeed G7

Class 3 Grounding (100Ω or more)

Multifunction Terminal

External Fault

Fault Reset

Multi-speed Ref 1

Multi-speed Ref 2

Multi-speed Ref 3

Not Used

Sequence CommonInsulated from (0V) terminal.

Shielded Sheath Cable Connection Terminal

Brake Release Command (Brake released at “closed”)250 VAC, 1 A or less30 VDC, 1 A or less

Fault Contact Output250 VAC, 1 A or less30 VDC, 1 A or less

Multifunction PHC Output48 V, 50 mA or less

ONOFF

REV

R

unSt

op

FWD

R

un

Brake Applying Command

Brake Self-holding

M1 M2

Brake Release Check

Accel/decel Time Selection 1

Emergency Stop (NO Contact)

External Baseblock *

* External baseblock signal baseblock at “closed”.

*

FWD Run/StopREV Run/Stop

Analog Monitor 2

Analog Monitor 1

Multifunction Analog Output

Note *


Spindle

X-axisCore Clamper

Z-axis

Motor

■ Similar Machines

・Polishers・Grinders・Small lathes・Plano miller feeders・Milling machines・Drilling machines・Presses

■Functions Available・Blade cutting loss prevention ・Wide range of constant output power・Control by digital inputs ・Vibration control

Principle Diagram of LathePrinciple Diagram of Lathe


Mechanism of NC LathesMechanism of NC LathesX-axis

Coupling Ball Screw

Z-axis Motor

CouplingBall Screw

Blade

Turret (Tool Base)

Spindle Position Sensor

Belt

Speed Changing

Timing Belt Spindle Motor

Motor for Core Clamper

Coupling

Core Clamper

WorkpieceS

pind

le

Ball Screw


Elevator ApplicationElevator Application

Sheave

Vector Control PWM Inverter

Braking Resistor, Braking Transistor (Externally Mounted)Inverter Section Converter Section

Induction Motor

Cur

rent

Det

ectio

n

AC Reactor

Cage Calling Signal

Entrance Calling Signal

Speed Feedback

Vector Control

Run Operation Signal

Load

Det

ecto

rC

age

Bal

ance

Wei

ght

Elevator Controller

Operation Control

Torque Ref. GeneratedPosition

Calculation Speed Ref. Generated

Speed/Position DetectionLoad Detection

3-phase AC Power Supply

PWM Control

Status Signal Fault Signal

AC Current Controller

Torque Compensation Speed Controller

Speed Ref.

Speed Reducer

■ Similar Machines・Escalators・Rope ways・Cable cars・Electric railcars・Electric automobiles

■Functions Available・Improvement of cage landing frequency・Soft-start with S-curve function ・Slip prevention at start/stop・Battery operation at a power failure


Chapter 6Chapter 6Inverter Drives Precautions Inverter Drives Precautions


○ × ×

(a) Vertical (b) Horizontal (b) Side by Side

InstallationInstallation


(a) Right and Left Space (b) Top and Bottom Space

MountingMountingAmbient temperature:

-10 to 40 ℃Ambient humidity:

90% RH or less

Vibration:

Less than 20 Hz

9.8 m/s2 or less

20 to 50 Hz

2 m/s2 or less

50mm or more

30mm or more 30mm or more

50mm or more

120mm or more

120mm or moreAir

Air


Bottom Cover Mounting Screw

Remove the unit top and bottom covers for the 20HP (15 kW) or less models (200-V class, 400-V class).

上部カバー (ワンタッチ )

TotallyTotally--enclosed Type Control Panel Installation enclosed Type Control Panel Installation

CoolingFin

Totally-enclosed Type Control Panel

Top CoverIn-panel Air Temperature at Top: –10 to +55℃Cooling Fin

Open chassis Type Inverter

Bottom Cover

Inverter Intake Air Temperature : –10 to +45℃

Ambient Temperature 40℃Bottom Cover

Top Cover(One-touch)

Ambient temperature:

+14 to 113ºF

(-10 to 45 ℃)

Ambient humidity:

90% RH or less

Vibration:

Less than 20 Hz

9.8 m/s2 or less

20 to 50 Hz

2 m/s2 or less


(a) Best Grounding

Inverter(1)

Inverter (2)

Inverter(3)

E E E

(b) Good Grounding

(c) Wrong Grounding

Inverter(1)

Inverter(2)

Inverter(3)

E E E

Inverter(1)

Inverter(2)

Inverter(3)

E E E

(A loop must not be made.)

Multiple Inverters GroundingMultiple Inverters Grounding


0 3 6 20 60

Continuous

100

807060

50

Frequency (Hz)

25%ED (or 15 minutes)



90

Allowable Load Characteristics of Allowable Load Characteristics of Standard MotorsStandard Motors

RunRun

StopｔR

T

％ED ＝ ―― ×100％ｔR

T

Torq

ue (%

)


Chapter 7 Chapter 7 Harmonics, Noise & Surge VoltageHarmonics, Noise & Surge Voltage


Noise Harmonics

Frequency Band High frequency (10 kHz or more) 40th to 50th harmonics (up to several kHz)

Main Source Inverter section Converter section Transmission Path ・Electric wire (conduction)

・Space (radiation) ・Induction (electrostatic,

electromagnetic

Electric wire

Influence Distance, wiring distance Line impedance Generating Amount ・Voltage variation ratio

・Switching frequency Current capacity

Failure ・Sensor malfunction ・Radio noise

・Overheat of capacitor for P.F improvement ・Overheat of generator

Corrective Actions ・Change the wiring route. ・Install a noise filter. ・Install INV. in a screened

box

・Install a reactor. ・12-phase rectification ・Sinusoidal wave power regeneration

converter 主な

Difference between Harmonics and NoiseDifference between Harmonics and Noise


Com

mer

cial

Pow

er

+Sm

ooth

ing

Cap

acito

r

Converter Section

Motor

Bridge Rectifier

Ｍ

Harmonics Current Generated by Rectifier Circuit

Noise Generated by High-speed Switching

Harmonics and Noise SourcesHarmonics and Noise Sources

Inverter Section


Fundamental Wave Current(at 50 or 60 Hz)

Harmonics Current(Example of 5th Level Harmonics)

(Amplitude Ratio: 0.3)

Distorted Wave Current

Fundamental Wave + Harmonics = Distorted Wave ACFundamental Wave + Harmonics = Distorted Wave AC(Harmonics Superimposed on Fundamental Wave)(Harmonics Superimposed on Fundamental Wave)

0 °°2


EDC

Converter

er es et

er-s er-t es-t es-r et-r et-s

Power Supply Phase Voltage

Ver-s

er

es

et

ｉr

ｉs

ｉt

EDC (Without Capacitor)

Power Supply Line Voltage

Power Supply Current Waveform

Phase R ir

Phase Sis

Phase Ｔit

Generation of Harmonics CurrentGeneration of Harmonics Current


(Harmonics Current Suppression)

(a) AC Reactor

+

Inverter

Motor

AC Reactor

Com

mer

cial

Pow

er

(b) DC Reactor

+

Inverter

Motor

DC Reactor

CommercialPower

Reactor ConnectionReactor Connection


Radio

Machine

Inverter

Power Supply Transformer

Amplifier

①②③ Conductive noise : Noise that flows out through the power supply line or grounding line④ Induction (electromagnetic, electrostatic)

: Noise transmitted by electromagnetic or electrostatic integration for the signal lines provided for the inverter main circuit wiring

⑤ Radiation : Noise radiated into the air through the inverter, motor unit, main circuit wiringthat work as antenna.

Noise Transmission PathsNoise Transmission Paths

Electronic Device

Sensor


Shielding (Steel) Plate Power LineSignal Line

Inverter M

Metallic Raceway Metallic Raceway

Wiring Separation by Rack or Duct

Induction Noise Suppression and Induction Noise Suppression and Metallic RacewayMetallic Raceway


インバータ

(a) Capacitive Filter (b) Inductive Filter (Zero-phase Reactor)

Power Supply

Pow

er S

uppl

y

(c) LC Filter

Conductive Noise SuppressionConductive Noise Suppression

InverterInverter

Power Supply

Inverter


InverterInverter

0V(Common)

0V(Common)

Junction Terminal

Inverter Noise Prevention Inverter Noise Prevention (Shielded Sheath Wire)(Shielded Sheath Wire)


Motor

線路インピーダンスの急変点（モータ端子部）で進行波の反射がおきる。

Progress and Reflection of Surge VoltageProgress and Reflection of Surge Voltage

(Leading Edge of One Pulse)

Inverter

Progressive Wave

Reflected Wave

Progressive wave reflects at the rapid changing point (motor terminal section) of line impedance.

(Twice Surge VoltageApplied to Terminals)


Without Filter →

(a) Test Circuit

[Inverter Output] [Motor Input]

(b) Result of Waveform Observation

(5μs/div, 250/div)

Expanded Diagram

With Filter →

Inverter Output Motor Input

IM

Surge Voltage Suppression by FilterSurge Voltage Suppression by Filter

Filter

Expanded Diagram

PWM Inverter


Filter

Motor Terminal Voltage(Without Filter )

Unless any filter is installed, surge voltage may be generated at the motor terminal, which may affect motor insulation.

Motor

Motor Surge Voltage Suppression by Filter Motor Surge Voltage Suppression by Filter

PWM Inverter

~ ~~

~ ~~


The solution to 400V class inverter drive problems1. Low surge voltage

Suppresses motor surge voltage, eliminating theneed for the motor surge voltage protection.

2. Low electrical noise (Radiated, Conductive)3. Low acoustic noise 4. Electrolytic corrosion of motor bearings due to shaft voltage

Features of 3Features of 3--level control level control


(b) Example of Shaft Voltage Measurement (between Shafts) (c) Shaft Voltage Waveform

(Hz)

Commercial Power Supply Drives

Actual Measurement of Shaft VoltageActual Measurement of Shaft Voltage

Commercial Power Drives

(Direct-coupling Side)(Opposite to Direct-coupling Side)

Shaf

t Vol

tage

(m

V)

Inverter

Inverter Drives

V: Measuring DeviceR: Non-inductive Resistor (1kΩ)

(Stator)

(Rotor)

(a) Example of Shaft Voltage Measuring Circuit Inverter: PWMMotor: 3.7 kW, 200 V, 4 polesV/f characteristics: Constant torque


Chapter 8Chapter 8Maintenance and Inspection Maintenance and Inspection


Failure PatternsFailure Patterns

Initial Failure Period

Accidental Failure Period Wear-out Failure Period

t

Specified Failure Ratio

Service Lifetime

Failu

re

Rat

ioλ

(t)

0ta tb


Place Item Checking Item

Schedule

DailyPeriodical

1-yr 2-yr

Whole

Peripheral environment Ambient temperature, humidity, dust, hazardous gases, oil mist, etc. ○

Whole unit No excessive vibration or noise. ○

Power supply voltage Check that main circuit voltage or control voltage is normal. ○

Main Circuit

Whole

① Megger check between main circuit terminal and ground terminal② No loose connections③ No traces of overheating in components④ Clean.

○○○

○

Connected conductor, Power supply

① No distortion in conductor② No breakage or deterioration (cracks, discoloration, etc.) in cables

○○

Transformer, Reactor No odor, excessive beats or noise ○

Terminal stand No damages ○

Smoothing capacitor① No liquid leakage② No projection (safety valve) or bulge③ Measure electrostatic capacity and insulation resistance.

○○

○

Relay, Contactor① No chattering at operations② Timer operation time③ No roughness on contacts

○○○

Resistor① No crack in resistor insulating material② No disconnection

○○

Control Circuit, Protective

Circuit

Operation check① Balance of output voltage between each phase by inverter single-unit operation② No failure in protective or display circuit by sequence protection test

○○

Component check

Whole① No odor or discoloration② No excessive corrosion

○

Capacitor No traces of liquid leakage or deformation ○

Cooling System Cooling fan① No excessive vibration or noise② No loose connections③ Clean the air filter.

○

○○

DisplayDisplay

① All lamps lights correctly.② Clean.

○○

Meter Indicated values are correct. ○

(From JEMA Information)

Daily Inspection and Periodical InspectionDaily Inspection and Periodical Inspection


NameStandard

Replacement PeriodMethod

Cooling fan 2 to 3 years Replace.

Smoothing capacitor 5 years Replace on investigation.

Breaker, relay －Determine what to do on investigation.

Timer －Determine after checking the operation times.

Fuse 10 years Replace.

Aluminum capacitor on PC board

5 years Replace on investigation.

Note : Operational Conditions・Ambient temperature : Annually 30℃ in average ・ Load ratio : 80% or less・ Operation ratio : 12 hours or less per day

Component Replacement Guidelines Component Replacement Guidelines


* Clamp meters available on markets have differences in characteristics between manufacturers.Especially, measured values tend to be extremely small at low frequency.

Precautions on MeasurementPrecautions on MeasurementInverter Approximate Waveform Element Meter

Input Voltage All effective values

Moving iron type voltmeter

Current All effective values

Moving iron type ammeter

Output Voltage Fundamental wave effective value

Rectifier type voltmeter (Model YEW2017, etc.)

Current All effective values

Moving iron type ammeter *


(a) Connection in Double Wattmeter Method

(b) Connection in Triple Wattmeter Method

Pow

er S

uppl

y

Motor Load Machine

Torque Meter Speed Meter

Motor Load Machine

Torque Meter Speed Meter

Inverter I/O MeasurementInverter I/O MeasurementPo

wer

Sup

ply

Inve

rter

Inve

rter

Torque meterLoardTachometer

MotorRecifier type voltmeterMoving iron type voltmeter

Electrodynamometer type wattmeterMoving iron type ammeter


Indications by Voltmeters Indications by Voltmeters with PWM Inverterwith PWM Inverter

Frequency (Hz)

Volta

ge (V

)

0.5-class Moving Iron Type Voltmeter

Digital ACpower meter

Tester(General-purpose)

Basic Wave Voltage (FFT)

0.5-class Rectifier Type Voltmeter

Inverter : 200V class 7.5kWMotor : 200Vclass 3.7kW, 4 poles

at no-load

Tester (in conformance to JIS C12-2 Class AA)


Hardware Block DiagramHardware Block Diagram

3-ph

ase

Pow

er S

uppl

y

External Sequence Signal

External Frequency Reference

Digital Operator

Motor

Frequency Meter

GateAlley

Base Drive Circuit

Inverter SectionDC IntermediateCircuit

Converter Section

ControlPower Supply

Ref

eren

ce In

put

Circ

uit S

eque

nce

Inpu

t Circ

uit

Freq

uenc

y R

efer

ence

VoltageDetection

CurrentDetection

Non-volatile Memory

Sequ

ence

Sig

nal O

utpu

t C

ircui

t


Purpose and Types of Protective FunctionsPurpose and Types of Protective FunctionsInverter Protection

Prot

ectio

nW

arni

ng

Motor Overheat Protection

Others

Operation status is not proper.

Prediction of protective function operation

Overcurrent OC

Overvoltage OV

Grounding GF

Main circuit undervoltage UV1

Cooling fin overheat OH

Braking transistor error rr

Inverter overload OL2

Motor overload OL1

Overtorque detection OL3/OL4 lit

CPU error CPF

Overtorque detection OL3/OL4 (blinking)

Undertorque detection UL3/UL4 (blinking)

Inverter overheat prediction OH2

Radiation fin overheat prediction OH


Main circuit overvoltage : OVApprox. 410 V(Approx. 820 V)

Approx. 380 V(Approx. 760 V)

Voltage at stall prevention during deceleration


Voltage at braking


Main circuit undervoltage : UV1 ※

DC Voltage

Voltage in the parentheses shows 400-V series.

Inverter output overcurrent : OC

Overload anti-time-interval characteristicsStall prevention level during running ※

Inverter rated output current

Current

200%

160%

100%

Stall prevention level during acceleration ※

150%

Level at Which Protective Function OperatesLevel at Which Protective Function Operates

※ Can be changed.


Chapter 9 Chapter 9 Reference Reference


(1) Difference between Inverters and Servos(1) Difference between Inverters and Servos

General-purpose Inverter Servos

What to Control

Mainly number of revolutions (torque) Mainly positions

Output 0.1 to 300 kW 0.003 to 55 kW

Motor General-purpose motors Exclusive-use motors with encoders

Positioning Accuracy

0.1 mm 0.001 mm

Maximum Torque

150% 300%

Start/Stop Frequency

Small Large

Price Less than ½ of servo -

Main Applications

● Fans, pumps, compressors● Conveyors, lifters, carts ● Elevators, electric railcars● Extruders, centrifugal separators● Paper machine● Iron & steel machine

● Semi-conductor manufacturing equipment

● Electronics parts mounting machine● Robots● Machine tools, printing,

material handling machines


(2) Principle of DC Motors(2) Principle of DC Motors

Commutator

Brush

Magnetic Field Direction

Magnetic Field Direction

F : Conductor (Rotor) Receiving Force

(View A)

: Current direction from front to back of paper face

: Current direction from back to front of paper face


(3) Speed Control of DC Motors(3) Speed Control of DC Motors

Speed Feed Back

Soft-Starter

Thyristor Converter

Speed Detection Generator (TG)

DC Motor

PhaseShifter

Field Power Supply

Current Reference

Speed Controller

Current Controller

Main Circuit Power Supply

FieldSpeed Reference

Speed Control Circuit


DC Motor

Current Detector

Thyristor ConverterTachometer-generator

(Phase Shifter)

(Main Circuit)

Motor Impedance

(Motor + Load) Inertia

Current Feed backSpeed

Feed back

LoadTorque

(4) Speed Control of DC Motors(4) Speed Control of DC Motors( Block Diagram )( Block Diagram )


(5) Configuration of IPM Motor Rotor(5) Configuration of IPM Motor Rotor

Stator Winding Stator

Permanent Magnet

Stator Winding

Stator

Secondary Conductor

Rotor

IPM Motor Induction Motor


(6) Comparison of IPM & Induction Motors(6) Comparison of IPM & Induction Motors

Comparison of Weights Comparison of Volumes

Output [kW] Output [kW]

Wei

ght [

%]

Volu

me

[%]

Induction Motor (100%)

IPM Motor

Induction Motor (100%)

IPM Motor


(7) Efficiency of IPM & Induction Motors(7) Efficiency of IPM & Induction Motors

0

50

100

誘導電動機ＩＰＭモータ

100％35％DOWN

65％

Elec

tric

al L

oss

[%]

Motor Loss

Efficiency improved by 5.5% (Example of 37 kW)

IPM MotorInduction Motor70

75

80

85

90

95

100

誘導電動機ＩＰＭモータ

81.2％86.7％

5.5％UP

Effic

ienc

y [%

]Comparison of Efficiencies

IPM MotorInduction Motor


(8) Rotor Cross Section of Super Econo(8) Rotor Cross Section of Super Econo--MotorMotor

Rotor Core

Slot

Magnet


(9) Comparison of IPM (VS(9) Comparison of IPM (VS--686SS5 Drive) and ISM (Super Econo686SS5 Drive) and ISM (Super Econo--motor)motor)Type Motor Configuration Configuration Characteristics Loss Remarks

Induction Motor

Synchronous Motor

Interior Permanent Magnet (IPM) Motor

VS-686SS5

Induction Synchronous Motor (ISM) Super Econo-

motor

Stator Winding

Rotor

Stator

Rotor Conductor

Stator Winding

Rotor

Stator

Braking Winding

Field Winding

Stator Winding

Rotor

Stator

(Example of 6P)

Stator Winding

Rotor

Stator

Permanent Magnet (Example of 4P)

Rotor Conductor

Pow

er C

omm

erci

al

(Speed Feedback)

VS-686SS5 Inverter

Field Power Supply

〕　〔－ r/minS)f(1P

120=Nspeed Rated ：

Speed

Torq

ue

Load Torque

〕　〔 r/minfP

120=Ns ： sSpeedSynchronou

P : No. of poles f : Frequency

〕　〔 r/minfP

120=NsN =

Speed

Pullout Torque

Pull-in Torque

Start Torque by Braking Winding

Speed

〕　〔 r/minfnP

120=NsnNn =

〕　〔 r/minfP

120=NsN =

Pullout Torque

Pull-in Torque

Starting Torque by Rotor Conductor squirrel(Cage)

Speed

Primary (stator) copper lossPrimary iron lossSecondary copper lossSecondary iron lossFloating load lossMechanical loss (Friction loss, windage loss)

Primary copper lossPrimary iron lossSecondary copper loss (Field winding loss)Floating load lossMechanical loss (Friction loss, windage loss)

Primary copper lossPrimary iron lossFloating load lossMechanical loss

Inverter loss

Primary copper lossPrimary iron lossFloating load lossMechanical loss

By applying 3-phase AC to the stator winding, a rotatingmagnetic field (rotating at synchronous speed) is made.Secondary current flows because the rotor rotates slower than synchronous speed (slip). Torque is generated by the rotating magnetic field and secondary current.Therefore, speed regulates by load torque. Torque generated by rotor braking winding is used for starting (acceleration). After completion of acceleration, field current flows to perform synchronous pull-in.

・Since rotating speed regulation is not occurred

Frequency is accelerated after synchronous pull-in by inverter. ・There is no loss at the secondary side. ・Speed control is performed by inverter frequency.

Acceleration is made by torque generated by rotor conductor at starting (acceleration). When speed is increased and closed to synchronous speed, the permanent magnet performs synchronous pull-in.・There is no secondary loss at synchronous speed. ・Field power supply is not needed.・No speed regulation.

Com

mer

cial

Pow

erPo

wer

Com

mer

cial

Pow

er C

omm

erci

al

Torq

ueTo

rque

Torq

ue

Permanent Magnet

(min-1)

(min-1)

(min-1)

(min-1)

(min-1)

Documents

Inverter_Training SE.pdf