Electricity Meter Solutions

TM

Freescale, the Freescale logo, AltiVec, C-5, CodeTEST, CodeWarrior, ColdFire,

ColdFire+, C-Ware, the Energy Efficient Solutions logo, Kinetis, mobileGT, PowerQUICC,

Processor Expert, QorIQ, Qorivva, StarCore, Symphony and VortiQa are trademarks of

Freescale Semiconductor, Inc., Reg. U.S. Pat. & Tm. Off. Airfast, BeeKit, BeeStack,

CoreNet, Flexis, MagniV, MXC, Platform in a Package, QorIQ Qonverge, QUICC Engine,

Ready Play, SafeAssure, the SafeAssure logo, SMARTMOS, TurboLink, Vybrid and

Xtrinsic are trademarks of Freescale Semiconductor, Inc. All other product or service

names are the property of their respective owners. © 2012 Freescale Semiconductor, Inc.

.

Martin Mienkina

System Application Engineer

June 2012

TM 2

Freescale, the Freescale logo, AltiVec, C-5, CodeTEST, CodeWarrior, ColdFire, ColdFire+, C-Ware, the Energy Efficient Solutions logo, Kinetis,

mobileGT, PowerQUICC, Processor Expert, QorIQ, Qorivva, StarCore, Symphony and VortiQa are trademarks of Freescale Semiconductor, Inc.,

Reg. U.S. Pat. & Tm. Off. Airfast, BeeKit, BeeStack, CoreNet, Flexis, MagniV, MXC, Platform in a Package, QorIQ Qonverge, QUICC Engine,

Ready Play, SafeAssure, the SafeAssure logo, SMARTMOS, TurboLink, Vybrid and Xtrinsic are trademarks of Freescale Semiconductor, Inc. All

other product or service names are the property of their respective owners. © 2012 Freescale Semiconductor, Inc.

• Understand electricity meter metrology requirements

• Become familiar with Freescale metering specific reference

designs and algorithm offerings

Tutorials covered in this presentation:

• Rogowski Coil Digital Integrator

• Explicit RMS Converter

• MK30 ADC16-PGA Measurement Chain

TM 3






• Introduction to Energy Meters

• Energy Metering Tutorial

• International Standards

• Current Sensor Interfaces

• Energy Calculation

• An Effective Metering System on Chip Based Solutions

• Enablement

• Summary

The first specimen of the AC kilowatt-hour meter produced on the basis of

Hungarian Ottó Bláthy's patent and named after him was presented by the

Ganz Works at the Frankfurt Fair in the autumn of 1889, and the first

induction kilowatt-hour meter was already marketed by the factory at the

end of the same year. These were the first alternating-current watt meters,

known by the name of Bláthy-meters.

Source: http://en.wikipedia.org/wiki/Electricity_meter

http://en.wikipedia.org/wiki/Alternating_current

http://en.wikipedia.org/wiki/Ott%C3%B3_Bl%C3%A1thy

http://en.wikipedia.org/wiki/Ganz

4 TM






Electromechanical meters

• Limited accuracy

• Manual reading

• Contains moving parts (aluminum ring)

Electronic meters

• MCUs, DSPs and ASICs based

• Accurate measurement

• Enhanced security

• Equipped with AMR

• No moving parts

Electricity Meter Types

Single phase

• Common in EU residential meters

• One voltage and one current measurement

• Use of shunt resistors prevail due to low system cost

Dual phase

• Common in US residential meters

• Two voltage and two current measurement

• Use of current transformers and Rogowski coils prevail

Three phase

• Used in industrial and commercial meters

• Three voltage and three current measurement

• Use of current transformers and Rogowski coils prevail

Measurement Types

• Active, reactive, apparent energy

• Active, reactive, apparent power

• RMS, peak values (voltage/current)

• Line frequency

• Power factor

• Temperature

Measured Quantities

5 TM






• IEC/EN compliant meters are typically quoted as class p: n(m)A

− Where n is the basic current

− m is the maximum current

− p is the accuracy class A(2%), B(1%), C(0.5%) – i.e. Class C: 5(60)A

• Standardized values

− Voltage 120-230-277-400-480 (V)

− Frequency rating 50 Hz

− Basic current 5-10-15-20-30-40-50 (A)

− Maximum current - multiples of basic current

− Active power P [W], reactive power Q [VAR] and apparent power S [VA] should be measured

• Factors impacting accuracy

• Mains frequency

• Load power factor

• Harmonics in voltage and current

• Temperature

• DC current

• Limited power consumption in current circuit

IEC/EN meter types dominate in

Europe, Turkey, Russia, India and

China.

6 TM






• Dynamic range @ accuracy required

• Common static power meter Class B: (5)60A requirements

Class Ireference

[A]

Imaximum

[A]

Itransitional

[A]

Itr = Iref/10

I minimum

[A]

Imin=0.5*Itr

Accuracy [%]

<imin; Itr>

Accuracy [%]

<Itr; Imax>

A 5 60 0,5 0,25 2,5 2

B 5 60 0,5 0,25 1,5 1

C 5 60 0,5 0,15 1 0,5

Dynamic range out of table Imax : Imin = 60 : 0,25 240 : 1 (DR)

accuracy required for class B meter 1,5% (err)

ADC requirements:

)2ln(

/ln errDRENOB

)2ln(

015.0/240ln96,13

1

Imax Itr Imin

e

7 TM






• ANSI C12.20 compliant meters are typically quoted as Class p%: r(m) − Where r is the reference current

− m is the maximum current

− p is the accuracy class 0.5%, 0.2% – i.e. Class 0.2: 30(200)A

• Standardized values − Voltage 120-240-277-480 (V)

− Frequency rating 60 Hz

− Current classes (reference amperes) 2(0.25)-10(2.5)-20(2.5)-100(15)-200(30)-

320(50) (A)

− Starting currents @ current classes 0.001, 0.01, 0.01, 0.05, 0.1, 0.16 (A)

− Active power P [W], reactive power Q [VAR] and apparent power S [VA] should

be measured

• Factors impacting accuracy − Mains frequency

− Load power factor

− Harmonics in voltage and current

− Temperature

− DC current

− Limited power consumption in current circuit

ANSI C12.20 meters are used in

US, Canada, Brazil and Mexico.

8 TM






• Dynamic range @ accuracy required

• ANSI C12.20 power meter Class 0.2: (30)200 requirements

Dynamic range out of table

Imax : Imin@ref = 200 : 3.0

66.6 : 1 (DR)

accuracy required for class

0.2 meter 0.2% (err)

Current in Amperes Maximum error deviation [%]

Current Class Accuracy class

Conditions 100 200 0.5 0.2

Starting current 0.1 0.1 - -

(1) Imin 1 2 ±1.0 ±0.4

(2) Imin@ref 1.5 3 ±0.5 ±0.2

(3) 3 6 ±0.5 ±0.2

(4) 10 20 ±0.5 ±0.2

(5) 15 30 ±0.5 ±0.2

(6) 30 60 ±0.5 ±0.2

(7) 50 100 ±0.5 ±0.2

(8) 75 150 ±0.5 ±0.2

(9) 90 180 ±0.5 ±0.2

(10) Imax 100 200 ±0.5 ±0.2

0.2

Imax Imin@ref Imin

e

)2ln(

/ln errDRENOB

)2ln(

002.0/6.66ln02.15

0.4

ADC requirements:

TM 9











• An Effective Metering System on Chip Based

Solutions

• Enablement

• Summary

10 TM






Mathematical description:

SENSE

SENSE

R Gain

2

Vref-Vadc

I

Pros: • Commonly used

• Simple to design

• Inexpensive

• No magnetic effects

Cons: • Self-heating due to power dissipation

• Parasitic inductance introduces phase shift at low power factors

• Non-isolated

Vref R R

R R

ADC

PDB

Power supply

N_INP

L_OUT

N_OUT

L_INP

Rsense

110/220V

Voltage divider

VDD

Isense

Rf

Rf

Cf

Cf

Anti-aliasing Filters

(-6dB per octave)

Vadc Gain

Voltage drop across shunt resistor is proportional to the amplitude of the current and frequency.

ISENSE(A) RSENSE( ) USENSE(VP-P)

0.02

250

14.4uV

0.15 106.0uV

60* 42.4mV

* Power losses 0.9W @ 60A

11 TM







N * Rb *Gain

)2

Vref-(Vadc

ISENSE

Pros: • Provides electrical isolation

• Current in secondary is proportional to current in primary

• Preferred for poly-phase meters

• Output voltage scaled to ADC input signal range

Cons: • CT introduces phase error from 0.1º to 7.0º

• Phase shift depending on current and temperature

• Load must never be disconnected from secondary winding

• Iron core can saturate at current level beyond its rated current or at a large DC

• Sensitive to magnetic tampering

• Expensive

Vref PDB

Power supply

N_INP

L_OUT

N_OUT

L_INP CT

110/220V

Voltage divider

VDD

Vadc

R

R

Rb 1 N

Isense Rf

Rf

Cf

Cf


(-6dB per octave)

ADC Gain

Turn Ratio=1:N

Courtesy of VACUUMSCHMELZE

ISENSE(A) Ratio USENSE(VP-P)

0.02 1:2500

Rb=12.5

282.8uV

0.15 2.1mV

60 0.848V

12 TM







(-6dB per octave)

The output voltage of the Rogowski

coil is proportional to the time-

differentiation (di/dt) of the current.

Pros: • Provides electrical isolation

• Capable of handling high current

• Low temperature drift

• Linear phase response

• No DC or high current saturation

• Immune to magnetic tampering

Cons: • Integration adds to extra circuitry

(software load)

• Interference (far field) pickup - limited by design or shielding


RR I**V FrKR

RVGAINVref

*2

Vadcwhere:

IR = rated primary current

Fr = frequency of sinusoidal waveform

KR = rotated transformer constant

Vref PDB

Power supply

N_INP

L_OUT

N_OUT

L_INP RC

110/220V

Voltage divider

VDD R

R

IRS

VRS

Rf

Rf

Cf

Cf

Vadc

ADC Gain ∫

Courtesy of PULSE ELECTRONICS ISENSE(A) Fr( /Hz) USENSE(VP-P)

0.02

8.33 (PA3202NL)

23.56uV

0.15 176.71uV

60 70.7mV

13 TM






Digital Integrator Block Diagram:

Explanation:

• HPF1: The first high pass filter to

prevent digital integrator overflow

(used to remove offset and low

frequency drift from input signal)

• Integrator: The numerical

integrator (use of the Bilinear

approximation is generally

preferred over forward/backward

Euler methods due to zero group

delay at higher frequencies

> 100 Hz)

• HPF2: The second high pass

filter required to remove offset

from the integrator output signal

Frequency & Phase Characteristics*:

0 50 100 150 200 250 -65

-60

-55

-50

-45

Frequency (Hz)

Magnitude r

esponse (

dB

)

0 50 100 150 200 250

0

2

4

6

8 x 10

-6

Frequency (Hz)

Magnitude e

rror

0 50 100 150 200 250 -91

-90

-89

-88

-87

-86

-85

Frequency (Hz)

Phase (

degre

es)

0 50 100 150 200 250

-5

-4

-3

-2

-1

0

Frequency (Hz)

Phase e

rror

(degre

es)

1.7Hz

1.3Hz

0.9Hz

0.5Hz

0.1Hz

1.7Hz

1.3Hz

0.9Hz

0.5Hz

0.1Hz

0.1Hz 0.5Hz

0.9Hz

1.3Hz

1.7Hz

0.1 - 1.7Hz

* Characteristics represents numerical integrator build of 1st order high pass.

Butterworth filters designed and analog filter designed for fcut = 0.1, 0.5, 0.9, 1.3

and 1.7 Hz and sampling rate fs=3000 Hz.

14 TM






Summary

• Small amplitude errors for filters cut off frequencies below 1.7Hz

• Phase error increases rapidly at higher filter cut-off frequencies

(above 0.1Hz)

• The lower the filter cut-off frequency, the more sluggish the

algorithm startup (initial offset removal)

HPF cut-off

frequency (Hz)

Amplitude

error (%)*

Phase error

(deg)*

Energy error

@ UPF (%)

Energy error

@ PF=0.5 (%)

0.1 0.0002 -0.22** 0.0007 -0.6643

0.5 0.0041 -1.15** 0.0201 -3.4561

0.9 0.0134 -2.05** 0.0640 -6.1318

1.3 0.0279 -2.98** 0.1352 -8.8693

1.7 0.0478 -3.89** 0.2304 -11.5200

* Amplitude and phase error determined for 50Hz input waveform.

** Fine compensation using delaying ADC conversion is possible and widely used.

TM 15












Solutions

• Enablement

• Summary

16 TM






Active Energy

Term Definition: • The electrical energy produced, flowing or supplied by an electric

circuit during a time interval, being the integral with respect to time of instantaneous Active Power, measured in units of Watt-hours or standard multiples thereof.

Equation:

0

)()( dttituWhttp://www.elexon.co.uk

Reactive Energy

Term Definition: • The integral with respect to time of the product of voltage and current

and the sine of the phase angle between them. Its is measured in units of volt-amperes reactive (VAR) and standard multiples thereof.

Equation:

http://www.elexon.co.uk

0

)()90( dttituVAR

Reactive Power

Term Definition: • Means the product of voltage and current and the sine of the phase

angle between them, measured in units of volt-amperes reactive (VAR) and standard multiples thereof.

Equation:

http://www.elexon.co.uk T

dttituT

Q0

)()90(1

TQVAR *

RMS Voltage & Current

Term Definition: • In electrical engineering the root mean square (RMS) or effective

value of a current is by definition such that the heating effect is the same for equal values of alternating or direct-current.

Equation:

http://en.wikipedia.org T

dttvalueT

rms0

2 )(1

Apparent Power

Term Definition: • In alternating-current power transmission and distribution apparent

power is the product of the RMS voltage and amperage.

Equation:

http://www.its.bldrdoc.gov

RMSRMS iuS

22 PQS

Active Power

Term Definition: • The product of voltage and the in-phase component of alternating

current measured in units of watts and standard multiples thereof, that is: 1000 Watts = 1 kW, 1000 kW = 1 MW

Equation:


dttituT

P0

)()(1

TPW *

S

P

tu

Q

17 TM






Example: u(t)=URMS*sqrt(2)*sin(2*pi*freq*t+alpha)

i(t)=IRMS*sqrt(2)*sin(2*pi*freq*t+0)

URMS=230V, IRMS=10A, freq=50Hz, alpha=0deg.

W=?

Matlab Calculus: Ud = sym('U_max*sin(2*pi*f*t+alpha)')

Id = sym('I_max*sin(2*pi*f*t+0)')

W = int(Ud*Id,0,'T')

subs(W,{'U_max','I_max','f','T','alpha'},{230*sqrt(2),10*sqrt(2),50,0.02,0})/3600

W = 0.0128 [watt-hours]

Model Simulation:

Term Definition: • The electrical energy produced, flowing or supplied by an electric

circuit during a time interval, being the integral with respect to time of instantaneous Active Power, measured in units of Watt-hours or standard multiples thereof.

Equation:

Processing/Calculation Steps: 1. Measure phase voltage u(t) and current i(t) samples

2. Remove offset from phase voltage measurements u(t)

3. Integrate product of phase voltage u(t) and current i(t) samples

Model:

0

)()( dttituW


―Active Energy Block‖ accumulates phase voltage and phase current multiple.

18 TM









VAR=?

Matlab Calculus: Ud = sym('U_max*sin(2*pi*f*t+alpha/180*pi)')


VAR = int(diff(Ud/sym('-2*pi*f'))*Id,0,'T')

subs(VAR,{'U_max','I_max','f','T','alpha'},{230*sqrt(2),10*sqrt(2),50,0.2,90})/3600

VAR = 0.128 [VAR-hours]

Model Simulation:

Term Definition: • Means the integral with respect to time of the product of voltage and

current and the sine of the phase angle between them. Its is measured in units of voltamperes reactive (VAR) and standard multiples thereof.

Equation:

Processing/Calculation Steps:

1. Measure phase voltage u(t) and current i(t) samples 2. Remove offset from phase voltage measurements u(t) 3. Shift phase voltage u(t) by 90º. 4. Integrate product of shifted phase voltage u(t-90º) and current

i(t) samples

Model:


―Reactive Energy Block‖ accumulates phase voltage and phase current multiple.

The phase voltage is shifted by 90º using ―90 degree phase shift block‖.

0

)()90( dttituVAR

19 TM






Example: u(t)=URMS*sqrt(2)*sin(2*pi*freq*t+alpha)+offset


IRMS=10A, URMS=230V, freq=50Hz, alpha=0deg, offset=0V.

Matlab Calculus: Ud = sym('U_max*sin(2*pi*f*t+alpha/180*pi)+offset')


UdRMS=sympow(symmul('1/T', int(Ud*Ud,0,'T')),1/2)

IdRMS=sympow(symmul('1/T', int(Id*Id,0,'T')),1/2)

subs(UdRMS,{'U_max','f','T','alpha','offset'},{230*sqrt(2),50,0.1,0,0})

UdRMS= 230.0 [V]

subs(IdRMS,{'I_max','f','T'},{10*sqrt(2),50,0.1})

IdRMS= 10.0 [A]

Model Simulation:

Term Definition: • In electrical engineering the root mean square (RMS) or effective

value of a current is by definition such that the heating effect is the same for equal values of alternating or direct-current.

In mathematics, the RMS is known as the quadratic mean, is a statistical measure of the magnitude of a varying quantity. It is especially useful when variations are positive and negative, e.g., sinusoids.

Equation:



3. Remove offset from phase current measurements i(t)

4. Calculate RMS values of the phase voltage URMS(t) and current IRMS(t).

Model:

http://en.wikipedia.org

―RMS Voltage & Current Averager‖ are based on the Explicit RMS Converter *, therefore

their output response is smoothed due to implied low pass filtering (IIR filter, first order,

fcut=2Hz).

T

dttvalueT

rms0

2 )(1

20 TM









P=?

Matlab Calculus: Ud = sym('U_max*sin(2*pi*f*t+alpha)')


P = symmul('1/T',int(symmul(Ud,Id),0,'T'))

subs(P,{'U_max','I_max','f','T','alpha'},{230*sqrt(2),10*sqrt(2),50,1.0,0})

P = 2300.0 [watts]

Model Simulation:

Term Definition: • The product of voltage and the in-phase component of alternating

current measured in units of watts and standard multiples thereof, that is: 1000 Watts = 1 kW, 1000 kW = 1 MW

Equation:



3. Accumulate instantaneous product of phase voltage u(t) and current i(t) per fixed time period.

4. Divide accumulated sum by time period if not equal to 1s

Model:

TPW *


dttituT

P0

)()(1

―Active Power Averager‖ is also based on the Explicit RMS Converter*, therefore their

output response is smoothed due to implied low pass filtering (IIR filter, first order,

fcut=2Hz).

21 TM









Q=?



Q = symmul('1/T',int(diff(Ud/sym('-2*pi*f'))*Id,0,'T'))

subs(Q,{'U_max','I_max','f','T','alpha'},{230*sqrt(2),10*sqrt(2),50,1.0,90})Ud = sym('U_max*sin(2*pi*f*t+alpha)')

Q = 2300.0 [VAR]

Model Simulation:

Term Definition: • The product of voltage and current and the sine of the phase angle

between them, measured in units of voltamperes reactive (VAR) and standard multiples thereof.

Equation:

Processing/Calculation Steps:

1. Measure phase voltage u(t) and current i(t) samples


3. Shift phase voltage u(t) by 90º

4. Accumulate instantaneous products of shifted phase voltage u(t-90º) and current i(t) per fixed time period

5. Divide accumulated sum by time period if period doesn‘t equal 1s

Model:

TQVAR *


―Reactive Power Averager‖ is also based on the Explicit RMS Converter*, therefore their

output response is smoothed due to implied low pass filtering (IIR filter, first order,

fcut=2Hz). The phase voltage is shifted by 90º using ―90 degree phase shift block‖.

T

dttituT

Q0

)()90(1

22 TM









S=?



UdRMS=sympow(symmul('1/T', int(Ud*Ud,0,'T')),1/2)

IdRMS=sympow(symmul('1/T', int(Id*Id,0,'T')),1/2)

S=UdRMS*IdRMS

subs(S,{'U_max','I_max','f','T','alpha'},{230*sqrt(2),10*sqrt(2),50,1.0,45})

S = 2300.0 [VA]

Model Simulation:

Term Definition: • In alternating-current power transmission and distribution, apparent

power is the product of the RMS voltage and amperage.

Equation:



3. Remove offset from phase current measurements i(t)

4. Calculate RMS values of the phase voltage URMS(t) and current IRMS(t)

5. Calculate apparent power by multiplying URMS(t)*IRMS(t)

Model:

http://www.its.bldrdoc.gov

―Apparent Power Block‖ calculates apparent power using arithmetic approach from the RMS

voltage and current samples. Performance of this block is therefore dependent on the

performances of the RMS voltage and RMS current calculations. The RMS voltage and RMS

current are based on the Explicit RMS Converters, therefore their output response is

smoothed by low-pass filtering (IIR filter, first order, fcut=2Hz). As URMS and IRMS contain

all harmonic information, the apparent power computed by arithmetic approach is a Total

Apparent Power.

RMSRMS iuSS

P

tu

Q

22 PQS

23 TM






0 0.05 0.1 0.15 0.2 0.25 0.3 0.35 0.4 0.45 0.5-1

-0.5

0

0.5

1

time(s)

u

0 0.05 0.1 0.15 0.2 0.25 0.3 0.35 0.4 0.45 0.50

0.2

0.4

0.6

0.8

1

time(s)

u2

0 0.05 0.1 0.15 0.2 0.25 0.3 0.35 0.4 0.45 0.50

0.2

0.4

0.6

0.8

time(s)

avg(u

2)

0 0.05 0.1 0.15 0.2 0.25 0.3 0.35 0.4 0.45 0.50

0.2

0.4

0.6

0.8

time(s)

sqrt

(avg(u

2))

0 0.05 0.1 0.15 0.2 0.25 0.3 0.35 0.4 0.45 0.5-1

-0.5

0

0.5

1

time(s)

u

0 0.05 0.1 0.15 0.2 0.25 0.3 0.35 0.4 0.45 0.50

0.2

0.4

0.6

0.8

1

time(s)

u2

0 0.05 0.1 0.15 0.2 0.25 0.3 0.35 0.4 0.45 0.50

0.2

0.4

0.6

0.8

time(s)

avg(u

2)

0 0.05 0.1 0.15 0.2 0.25 0.3 0.35 0.4 0.45 0.50

0.2

0.4

0.6

0.8

time(s)

sqrt

(avg(u

2))

LPF

X2

XP

LPF

u

LPF

X2

i i2

avg(i2)

u2

avg(u2)

avg(i2)

avg(u2)

PGA Input Signal Range:

Equation:

Input Signal: Umax*sin(2*pi*f*t)

Step 1: Umax2*sin(2*pi*f*t)

0 0.05 0.1 0.15 0.2 0.25 0.3 0.35 0.4 0.45 0.5-1

-0.5

0

0.5

1

time(s)

u

0 0.05 0.1 0.15 0.2 0.25 0.3 0.35 0.4 0.45 0.50

0.2

0.4

0.6

0.8

1

time(s)

u2

0 0.05 0.1 0.15 0.2 0.25 0.3 0.35 0.4 0.45 0.50

0.2

0.4

0.6

0.8

time(s)

avg(u

2)

0 0.05 0.1 0.15 0.2 0.25 0.3 0.35 0.4 0.45 0.50

0.2

0.4

0.6

0.8

time(s)

sqrt

(avg(u

2))

Step 2: avg(Umax2*sin(2*pi*f*t))

Step 3: sqrt(avg(Umax2*sin(2*pi*f*t)))

0 0.05 0.1 0.15 0.2 0.25 0.3 0.35 0.4 0.45 0.5-1

-0.5

0

0.5

1

time(s)

u

0 0.05 0.1 0.15 0.2 0.25 0.3 0.35 0.4 0.45 0.50

0.2

0.4

0.6

0.8

1

time(s)

u2

0 0.05 0.1 0.15 0.2 0.25 0.3 0.35 0.4 0.45 0.50

0.2

0.4

0.6

0.8

time(s)

avg(u

2)

0 0.05 0.1 0.15 0.2 0.25 0.3 0.35 0.4 0.45 0.50

0.2

0.4

0.6

0.8

time(s)

sqrt

(avg(u

2))

Source: Charles Kitchin, Lew Counts, ―RMS to DC Conversion

Application Guide‖, 2nd Edition, Analogue Devices, 1986.

)( 2uavgURMS

24 TM






Summary

• Frequently used for RMS current, RMS voltage, active power

and reactive power calculations

• Square root with 16-bit output dynamic range was found

sufficient for representing non billing quantities (all above)

• Executes in less than 100 instruction cycles on ARM Cortex-

M4™ (compiled by IAR EW for ARM, full optimization, code

inlining, the additional LPF {1st order} added to smooth square

root output)

TM 25












Solutions

• Enablement

• Summary

26 TM






• Cost optimized

• Large choice

• Industry standard cores

• Analog integration

• Lowest 32-bit power

Ext. AFE KA/LA8

LG32

LH/LL64 (S08,16-bit,8K-64K)

Int. AFE

Ext. AFE

Apps Cont.

Single

Phase Three

phase

2008 2010 2012 2007 2009 2011

EM128 (SR) (CF,128K)

Flow Coming

Next

MZ60 (China)

GW/LL64 (S08,16-bit,32K-64K)

MG64 (China)

AFE

Kinetis : K10-K30 (M4,64K-1M,crypto)

Next Gen

Met+App

Flow NPI

Next-Gen Met

Next Gen

Single Chip

Smart AFE

K30/K10/K12 (AFE,Welmec, M4)

(256K-1M)

K30/K10/K12 (Welmec, M4,)

(128K-1M)

32-bit

8-bit

32-bit

32-bit

32-bit

EM256 (CT) (CF,256K)

27 TM






Development

Tools

Bundled IDE

w/ Processor

Expert

Bundled OS

USB, TCP/IP,

Security

Modular Tower

H/ware

Development

System

Application

Software

Stacks,

Peripheral

Drivers & App.

Libraries

(Motor Control,

HMI, USB)

Broad 3rd party

ecosystem

Common

Digital IP

CRC

I2C

SAI (I2S)

UART/SPI

Programmable

Delay Block

External Bus

Interface

Motor Control

Timers

eSDHC

RTC

Common

Analog IP

16-bit ADC

Programmable

Gain Amplifiers

12-bit DAC

High-speed

Comparators

Low-power

Touch Sensing

Common

System IP

32-bit ARM

Cortex-M4™ Core

w/ DSP Instructions

Next Generation

Flash Memory

High Reliability,

Fast Access

FlexMemory w/

EEPROM capability

SRAM

Memory

Protection Unit

Low Voltage,

Low Power Multiple

Operating Modes,

Clock Gating

(1.71V-3.6V with 5V

tolerant I/O)

DMA

-40 to 105 °C

K70 Family 512 KB-1 MB,

196-256pin


100-256pin

K50 Family 128-512 KB,

64-144pin


64-144pin


64-144pin


32-144pin


32-144pin

28 TM






• Flexible, low power LCD interface

− Segment LCD Blink mode lowers average power

− Segment fail detect prevents erroneous readouts and

reduces LCD test cost

− Front/back plane reassignment provides pin-out

flexibility and allows configuration changes in firmware

• Diverse communications suite

− A multitude of serial interfaces, with UART support for

ISO7816 SIM/Smart Cards and IrDA interfaces

− Dual CAN for industrial network bridging

• System reliability and safety

− Hardware cyclic redundancy check safeguards

memory contents and communication data

− Memory Protection Unit – increase software reliability

− Independently-clocked watchdog prevents code

runaway for fail-safe applications e.g. IEC60730

• Hardware and software compatibility

− Common packages and peripherals across families

enable rapid feature growth with minimal hardware

and software disruption

• Built-in voltage regulator (K40)

− 5V regulator input with 3.3V regulated output

− 3.3V regulated output can power MCU and also external

components (source current up to 120mA)

Family USB OTG + DCD Segment LCD

K30 - X

K40 X X

For Segment LCD Applications

Up to 512KB Flash

Memory

Up to 128KB

SRAM

FlexMemory:

up to 4KB EEPROM

or 256KBFlash

CrossBar Switch (XBS)

16-ch

DMA

FlexBus

Peripheral Bus Controllers (x2)

Up to 100MHz ARM Cortex-M4 Core

DSP

1.25DMIPs/MHz

Clock Module: 2 Crystal inputs

2 internal oscillators

PLL and FLL

Secure Digital Host

Controller

Memory Protection Unit

K30 Family Block Diagram

Timers

3x FlexTimers

Carrier Modulator Timer,

Programmable Interrupt Timer,

Low Power Timer,

Programmable Delay Block

Analog

2x 16-bit SAR ADC 2x 12-bit DAC

3x High Speed Comparators

2x Programmable Gain Amplifiers

Internal Voltage Ref (1.2V)

Communications

2x I2C 6x UART 3x DSPI 2x CAN

IIS

32-bit Cyclic Redundancy

Check

Segment LCD (8x40 /4x44)

Low Power Xtrinsic

Touch Sensing

Interface

Watchdog +

External Watchdog

Monitor

Up to 98 GPIO

Kinetis documentation: www.freescale.com/webapp/sps/site/homepage.jsp?code=Kinetis

http://www.freescale.com/webapp/sps/site/homepage.jsp?code=KINETIS

29 TM






Needs Kinetis Solution

Cortex-M4 CPU M4 core (DSP functionality) up to 100 MHz

Low Power 298uA*/MHz Run Current

Down to 1.47uA** @VLLS1

Data Storage FlexMemory (Up to 4kB EEPROM, Dual Flash Bank). Fast Flash Programming (70us)

Flash Update Flash swap, security and protection. CRC32 for code check up

User Interface Embedded LCD controller (integrated voltage generators)

Communication Up to 6 UARTS, 3 SPIs and 2 IIC.

Memory Scalability From 64 KB to 512 KB of Flash. From 16 KB to 128 KB of RAM

Time Keeping RTC module with separate Vbat and Crystal compensation (Correction range ~ ±.12ppm

.. ~ ±3900ppm)

Analog Modules High Speed ADC with integrated PGA. 12-bit DAC. HSCMP. Built-in 1.2 V reference

33 ppm/C with dedicated output pin.

Packages 64LQFN, 64LQFP, 80LQFP, 81 BGA, 100LQFP, 104BGA, 144LQFP, 121BGA, 144BGA

* Typical run mode current — 72MHz core clock, 36MHz bus clock, and 24MHz flash clock. MCG configured for FEE mode. All peripheral clocks disabled.

** Typical very low-leakage stop mode 1 current at 3.0 V and –40 to 25°C

30 TM






ADC0

ADC1

PGA0

1x-64x

PGA1

1x-64x

PGA0_DP/ADC0_DP0/ADC1_DP3

PGA0_DM/ADC0_DM0/ADC1_DM3

ADC0_DP1

ADC0_DM1

ADC1_DP1

ADC1_DM1

PGA1_DP/ADC1_DP0/ADC0_DP3 PGA1_DM/ADC1_DM0/ADC0_DM3

DAD1

DAD0

DAD2

DAD3

DAD3

DAD2

DAD0

DAD1

The Programmable Gain Amplifier (PGA) is designed to increase the dynamic

range by amplifying low-amplitude signals before they are fed to the 16-bit ADC.

31 TM






The formula for PGA differential input signal swing

of the ADC16-PGA measurement chain is:

𝑽𝑷𝑷𝑨𝑫𝑪,𝑫𝑰𝑭 = 𝐦𝐢𝐧 𝑽𝒙−𝟎.𝟐,𝑽𝑽𝑹𝑬𝑭−𝑽𝒙 ×𝟒

𝑮𝑨𝑰𝑵 [𝑽]

(1)

where: 𝑽𝒙 is 700mV

𝑽𝑽𝑹𝑬𝑭 is 1.2V

𝑮𝑨𝑰𝑵 is PGA gain 1, 2, 4, 8, 16, 32 and 64.

ADC16 digital output range is expressed as follows:

𝑨𝑫𝑪𝑶𝑼𝑻 = 𝑽𝑷𝑷𝑨𝑫𝑪,𝑫𝑰𝑭

𝟐×𝑽𝑽𝑹𝑬𝑭× 𝑮𝑨𝑰𝑵 × 𝟐

𝐍 [𝑳𝑺𝑩]

where: 𝑵 is number of bits for given ADC16

conversion mode.

Gain=x64 ADC Measurement Use-Case:

ADC16

615.6250 mV ADC16_DP

ADC16_DM

PGA_DP

PGA_DM

0V

PGA

x64

584.3750 mV 0.7V

1.2 V

0.2V

0.6 V

0.6 V

0V

0.7V

1.2 V

0.2V

0V

1.0 V

-1.0V615.6250 mV

584.3750 mV

PGA Input Signal Range

PGA Input Signal Range:

ADC Digital Output (PGA Enabled, Gain=x64).

0 0.001 0.002 0.003 0.004 0.005 0.006 0.007 0.008 0.009 0.01

-3

-2

-1

0

1

2

3

x 10 4

time [s]

adc o

utp

ut

[LS

B]

Theoretical

PGA GAIN VPP,DIF [mV] ADCOUT [LSB]

x01 2000

54613

x02 1000

x04 500

x08 250

x16 125

x32 62.5

x64 31.25

32 TM






Summary

• Kinetis K30 devices feature two 16-bit ADCs. Each ADC

contains a differential input channel with PGA.

• Each ADC has two status and control registers as well as two

result registers, thus up to four conversions can be initiated by

hardware without software intervention.

• Up to two measurements can be trigger either simultaneously

or with precisely defined delay with the help of the

Programmable Delay Blocks – the trigger setup is optimized for

use in 1-phase electricity meters.

33 TM






Secure,

Prepaid

MK30 with

NFC 1Q12

34 TM






Block diagram Photo

More information: http://www.freescale.com/webapp/sps/site/prod_summary.jsp?code=RDMK30XSPEM

http://www.freescale.com/webapp/sps/site/prod_summary.jsp?code=RDMK30XSPEM

35 TM






Key Features: • 5(60)A current range, nominal current is 5A, peak current is 60 A

• Four quadrant measurement

• 85V...264V, 50/60 Hz voltage range

• Active and reactive energy accuracy IEC50470-3 Class B, 1%

• Line frequency measurement (for precision zero-cross detection)

• Cost-effective shunt resistor sensing circuit implementation

• Cost-effective bill of materials (BOM)

• Low-power modes effectively implemented, including the use of the built-in RTC

• LCD display, 4x31 segments including charge pump

• Values shown on the LCD: V,A,W,Var,VA, kWh, kVarh, cos , Hz, time, date

• Tamper detection via two tamper buttons (event is stored in FlexMemory)

• Built-in user push-button

• LEDs pulse outputs (kWh, kVARh)

• IEC1107 infrared hardware interface

• Optically isolated RS232 interface

• 2.4 GHz RF1322x interface (I2C Daughter Card) for connection to a ZigBee® network

• MQXTM based for advanced markets

• Multiple advanced metering algorithms (FFT, filter-based method)

36 TM






-2

-1.5

-1

-0.5

0

0.5

1

1.5

2

0.01 0.1 1 10 100 err

or[

%]

current[A]

Temp. drift of active energy error for MK30 1-ph meter (Vbias tied on VREF)

-25°C

0°C

22°C

45°C

70°C

min.

max.

According to EN50470-3, Class B 5(60)A, errors

represents results at UPF

37 TM






Where: ―Fs‖ is sampling frequency

―N‖ is number of samples per voltage cycle

―k‖ series of harmonics 1 .. N/2-1

More information: http://cache.freescale.com/files/32bit/doc/app_note/AN4255.pdf

http://cache.freescale.com/files/32bit/doc/app_note/AN4255.pdf

38 TM






Conditions

• Implementation of FFT algorithm to ARM core (MK30X)

• Separation of real and imaginary parts of FFT signal to fix part (32-bits) and

remainder part (16-bits) – in total 48-bits (good precision for most of

applications)

Advantages of realization

• The same precision for both energies (active, reactive) in comparison to other

computing methods – depends only on AFE (HW) of the meter, not on software.

• Frequency analysis of input signal – ability to compute total harmonic distortion

• Offset removal (0-harmonic is missed for power computing)

Disadvantages of realization

• Adjustable sampling rate necessary to compensate for frequency changes

• Higher computational power - 10,2 MIPS for 6400 Hz sampling rate (CPUCLK =

48 MHz)

39 TM






• Demo purpose:

− To provide working solution for accuracy evaluation

− To specify schematic and BOM (low-cost)

− To verify accuracy

• Product Features and Specifications:

− Design Reference Manual (DRM122)

− AN4255 - FFT-based algorithm for metering applications

− Quick Start for MK30EMETERMQX

− MQX Reference Manual and MQX User‘s Guide

− 1322x Low-Power Node Reference Manual

− Device development tools: MK30EMETERMQX

− Device documentation: MK30X256

http://cache.freescale.com/files/microcontrollers/doc/ref_manual/DRM122.pdf?fpsp=1&WT_TYPE=Reference Manuals&WT_VENDOR=FREESCALE&WT_FILE_FORMAT=pdf&WT_ASSET=Documentation

http://cache.freescale.com/files/32bit/doc/app_note/AN4255.pdf?fpsp=1&WT_TYPE=Application Notes&WT_VENDOR=FREESCALE&WT_FILE_FORMAT=pdf&WT_ASSET=Documentation

http://cache.freescale.com/files/microcontrollers/doc/user_guide/MK30XEMETERMQX_QS.pdf?fpsp=1&WT_TYPE=Quick Reference Guides&WT_VENDOR=FREESCALE&WT_FILE_FORMAT=pdf&WT_ASSET=Documentation

http://cache.freescale.com/files/32bit/doc/ref_manual/MQXRM.pdf?fpsp=1&WT_TYPE=Reference Manuals&WT_VENDOR=FREESCALE&WT_FILE_FORMAT=pdf&WT_ASSET=Documentation

http://cache.freescale.com/files/32bit/doc/user_guide/MQXRTCSUG.pdf?fpsp=1&WT_TYPE=Users Guides&WT_VENDOR=FREESCALE&WT_FILE_FORMAT=pdf&WT_ASSET=Documentation

http://www.freescale.com/webapp/sps/site/homepage.jsp?code=MQX_HOME&fsrch=1&sr=3

http://www.freescale.com/webapp/sps/site/prod_summary.jsp?code=K30_100&webpageId=132640837728673979DDA9&nodeId=01624698C9DE2DDDA9&fromPage=tax

40 TM






3-ph E

Meter

MK30

2Q12

41 TM






2Q12

42 TM






Key Features:

− 5(100)A current range, nominal current is 5A, peak current is 100 A

− Four quadrant measurement

− 85V...264V, 50/60 Hz voltage range

− Active and reactive energy accuracy IEC50470-3 Class B, 1%

− Line frequency measurement form all 3 phases (for precision zero-cross detection)

− Current transformers sensing circuit implementation

− Cost-effective bill of materials (BOM)

− Low-power modes effectively implemented, including the use of the built-in RTC

− LCD display, 4x44 segments including charge pump

− Values shown on the LCD: V,A,W,Var,VA, kWh, kVarh, cos j, Hz

− Tamper detection via ELECTRONIC TILT PMA8491Q sensor and tamper buttons (event is stored

in FlexMemory)

− Built-in user push-button

− LEDs pulse outputs (kWh, kVARh)

− IEC1107 infrared hardware interface

− Optically isolated RS232 interface

• AMU and UMI connectors interface, could be use for (I2C Daughter Card) for connection to a

ZigBee® network

• Multiple advanced metering algorithms (FFT, filter-based method)

2Q12

TM 43









• Sensor Interfaces



Solutions

• Enablement

• Summary

44 TM






• Special Edition – Free. The following limitations apply -

− Unlimited assembly code

− Up to 32KB of C code for HC(S)08/RS08 derivatives

− Up to 64KB of C code for V1 ColdFire/ColdFire+ derivatives

− Up to 128KB of C code for V2-V4 ColdFire and Kinetis derivatives

• New Project Wizard – Create a project in as few as six clicks

• MCU Change Wizard – Re-target to a new RS08, HCS08, ColdFire, ColdFire+ or Kinetis processor

in as few as six clicks

• LiveView – Allows registers, memory and global variables to be monitored without stopping the

processor

• Processor Expert – Creates tested, optimized initialization code and low-level drivers tuned to

application needs and selected Freescale derivative

• Built-in knowledgebase immediately flags resource conflicts and incorrect settings, so errors are caught early in

design cycle

− Processor Expert for Kinetis is fully integrated with MQX via RTOS adapter component

• Trace and profile support for on-chip trace buffer and real-time collection (external probe)

• Full debug support for low power modes

− Handles entry into and continuation of debug after exiting Low Power and Very Low Power modes.

Free

Compiler

up to

128KB!

45 TM






• Leading supplier of MCU development tools

− ANSI C/C++ compilers, Debuggers and Simulation

− Middleware components

• Extensive Device Database®

− Directory of over 700 supported ARM MCUs

• Established support

− Phone, Email, Web and User Group Support

• Huge installed base

− 100K+ users world wide

• Best-in-class compilation tools

− Architecture-specific optimizations

− Smaller and faster code reduces system cost

Products:

• MDK-STANDARD-FREESCALE: Supports any Kinetis

Cortex-M4 series device, $745 (1year license with no code

limits)

• MDK-Lite (32K Code Limited): $0

• MDK-Standard (T) (1 Yr Lic): $1958

• MDK-Basic (B) (256KB limit): $2695

• MDK-Standard: $4895

• MDK-Standard (F) (3 seats floating): $5874

• MDK-Professional: $9995

• MDK-Professional (F) (3 seats floating): $11994

• MicroLib optimized C Libraries − Superset of standard ARM C Library

− Optimized for embedded applications

• Additional support for the Cortex-M4 − Supports Thumb2 Instruction sets

including DSP and FPU

− CMSIS Signal Processing Library

support

http://www.keil.com/

46 TM






Evaluation

versions on

www.iar.com

www.iar.com/ewarm to download

• The most widely used C/C++ tool chain for ARM MCUs

• Professional and global technical support organization (10 offices)

• Reliable, powerful and easy to use

• Advanced trace debug functionality based on ETM and SWO

• Support for Kinetis 10/20/30/40/60/70, i.MX, ColdFire+ and

ColdFire

• Freescale MQX™ RTOS integration

• Project examples for the Freescale Tower system

Products:

• EWARM-CM-FSL: Supports any Kinetis Cortex-M4 series device,

$2500 (1-year license), available now via Freescale ‗Buy Direct‘

http://www.freescale.com/webapp/sps/site/prod_summary.jsp?cod

e=EWARM-CM-FSL&fsrch=1&sr=2

• EWARM-CM: Supports all ARM Cortex-M devices including

Cortex-M4

• EWARM-BL (BaseLine): Supports all ARM cores with a limit in

code size of 256 KB

• EWARM: Supports all ARM cores

http://www.iar.com/ewarm

http://www.freescale.com/webapp/sps/site/prod_summary.jsp?code=EWARM-CM-FSL&fsrch=1&sr=2






47 TM






Free scalable, fully-featured and proven

RTOS with 32-bit MCUs

− Full-featured and powerful

BSPs incorporate tightly integrated RTOS,

Middleware (USB, TCP/IP stacks), file system, and

I/O drivers

Designed for speed and size efficiency

− Market proven

Available on Freescale processors for > 15 years

Used in millions of products including medical and

heavy industrial applications

− Simple and scalable

As small as ~10KB for smallest implementation, or

scale up to support sophisticated networking and

threading

Intuitive API & modular architecture enables straight-

forward fine-tuning of features

Production source code provided

− Similar to other “pay-for” software OS

Software integration

headache

Integrated MQX Solution

$95K

of free

Software

Stable

Upgradable

Easy to maintain

48 TM






Download from: www.freescale.com/webapp/sps/site/prod_summary.jsp?code=FREEMASTER

Application control

and monitor

Real-time eTPU

operation monitor

Live graphs,

variable watches,

and graphical

control page

Supports: - HCS08, HC12, HCS12 and HCS12X BDM

- 56F8000, 56F8100 and 56F8300 JTAG

- SCI driver (FMASTERSCIDRV) for all

platforms

http://www.freescale.com/webapp/sps/site/prod_summary.jsp?code=FREEMASTER

49 TM






TWR-SER

TWR-SER2

TWR-PROTO

Peripheral

Modules ($15 – $149)

Processor

Modules ($39-$119)

TWR-MEM TWR-LCD TWR-SENSOR-PAK

TWR-SENSOR-PAK-AUTO

TWRPI-MMA6900

TWRPI-MPL115A

TWR-ADCDAC-LTC

TWR-WIFI-RS2101

TWR-WIFI-G1011MI

TWR-WIFI-AR4100

TWR-MCF51JE

TWR-MCF51CN

TWR-MCF51MM

TWR-MCF51QM

TWR-MCF5225X

TWR-MCF5441X

TWR-MCF51JF

MED-EKG

TWR-S12GN32

TWR-S12G128

TWR-S08LL64

TWR-S08LH64

TWR-S08JE128

TWR-S08MM128

TWR-S08GW64

TWR-S08UNIV

TWR-S08PT60

TWR-MPC5125 TWR-56F8257 TWR-K60N512

TWR-K40X256

TWR-K60D100M

TWR-K40D100M

TWR-K53N512

KWIKSTIK-K40

TWR-K20D50M

www.freescale.com/tower

8bit 16bit DSC 32bit - ColdFire 32bit – Power Arch 32bit Kinetis

Serial Prototyping Memory Sensors &

Plug-Ins Displays Wi-Fi

Analog Audio Mesh Networking

Medical

TWR-AUDIO-SGTL TWR-RF-SNAP

http://www.freescale.com/tower

TM 50









• Sensor Interfaces



Solutions

• Enablement

• Summary

TM 51






• Freescale offers wide range of metering specific reference

designs and application notes.

• Metering algorithms are tested according to EN50470-3

(active energy) and IEC 62053-23 (reactive energy) as well

as ANSI C12.20 standards.

• Performance and accuracy of all Kinetis MK30, ColdFire

EM256, S08GW64 and S08LH64 reference designs have

been thoroughly evaluated on metering test bench.

• The EMC testing is performed according to EN 61000-4-X

basic standards taking into account regional specifics and

preferences.

TM 52






Tweeting? Please use hashtag

#FTF2012

Facebook.com/Freescale Tag yourself in photos

and upload your own!

Session materials will be posted @ www.freescale.com/FTF Look for announcements in the FTF Group on LinkedIn or follow Freescale on Twitter

http://www.freescale.com/FTF

TM

Documents

Electricity Meter Solutions