comtrade file manipulationver1

©2012 Doble Engineering Company. All Rights Reserved

ComTrade Data For Transient

Testing

Jay Gosalia

Doble Engineering Company

©2012 Doble Engineering Company.

All Rights Reserved2

What is ComTrade & History of ComTrade Standard

Basics of ComTrade Data structure

Create ComTrade files and review data

Manipulation of ComTrade Data

Summary and advantages

Presentation Topics

• PSRC working group H5

• Common format for Transient data Exchange

– IEEE C37.111-1991

– IEEE C37.111-1999

– IEEE C37.111-2013

ComTrade Standard


• COMmon format for TRAnsient Data Exchange

– IEEE C37.111-1991

– IEEE C37.111-1999

– IEEE C37.111-2013

ComTrade Standard


• COMmon format for TRAnsient Data Exchange

– IEEE C37.111-1991

– IEEE C37.111-1999

– IEEE C37.111-2013

• Not a standard for data communication

ComTrade Standard


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History of COMTRADE Standard

IEEE C37.111-1991, June 27, 1991

IEEE C37.111-1999, March 18, 1999

IEC 60255-24 Ed 2.0

IEEE C37.111-2013, April 30, 2013

IEC 60255-24, Ed 1.0 2001

History of COMTRADE Standard


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• Removable diskettes for data exchange

• MS DOS File format

• Files for COMTRADE Record

– Data file *.DAT

– Configuration file *.CFG

– Header file *.HDR

– Information file *.INF (added in 1999)

ComTrade Standard Structure


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• Free form ASCII file

• Recording information

– Substation location

– System impedance

– Transformer details

– System conditions before and after fault

Header File (Optional)


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Pre defined format in ASCII

Data in Rows and Columns

Sample number and time

Analog channel values : Voltage and / or current

Digital channels status :Breaker status, Relay contacts (0 or 1)

Data file *.DAT


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Data file : ASCII DATA

5,667, 760,1274,0,1<CR/LF>

Sample Number

Time stamp

in microseconds

Analog Channel Data Values

Digital Channel Status


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Comtrade Data

Sample Value = a X + b

Sample Multiplier

Data Value in .DAT file

Offset


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Analog to Digital Offset Mapping

Digital

Analog

0 4095

a = (max - min) / 4095b = min

max

min

Y = aX + b


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Configuration file *.CFG

Pre defined format in ASCII

Info. to convert data to analog values

Frequency

Data recording rates

Date & time of first sample & trigger


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Configuration File Example

Sample data, 1 <CR,LF>

2, 1A, 1D <CR,LF>

1, Current, IA, L2, A, 0.0069061827, -8.28427, 0.0, 0, 8191 <CR,LF>

1, Breaker A, 0 <CR,LF>

60 <CR,LF>

1 <CR,LF>

1200, 240 <CR,LF>

02/24/98,08:15:22.000000 <CR,LF>

02/24/98,08:15:22.100000 <CR,LF>

ASCII <CR,LF>


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Analog Channel DATA

1, Current, IA, L2, A, 0.0069061827, -28.28427, 0.0, 0, 8191 <CR/LF>

Minimum Value

Maximum value

Channel

Number

Channel

Name

Channel

Phase

Circuit

Unit

Scaling

Factor “a”

Offset

Factor “b”

Skew


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2, 1A, 1D <CR,LF>



60 <CR,LF>

1 <CR,LF>

1200, 240 <CR,LF>

02/24/98,08:15:22.000000 <CR,LF>

02/24/98,08:15:22.100000 <CR,LF>

ASCII <CR,LF>


All Rights Reserved



2, 1A, 1D <CR,LF>



60 <CR,LF>

1 <CR,LF>

1200, 240 <CR,LF>

02/24/98,08:15:22.000000 <CR,LF>

02/24/98,08:15:22.100000 <CR,LF>

BINARY <CR,LF>


Create ComTrade Files for

Transient Testing

20



Power System Model



System Event Data



Power System States



State Simulation



State Simulation Data : Graphics



Create ComTrade Data



*.cfg file

Doble,1,1999

6, 6A, 0D

1,VA,,,V,0.0028633,0,0,-32768,32767,1,1,S

2,VB,,,V,0.0028633,0,0,-32768,32767,1,1,S

3,VC,,,V,0.0028633,0,0,-32768,32767,1,1,S

4,IA,,,A,0.003934413,0,0,-32768,32767,1,1,S

5,IB,,,A,2.25E-04,0,0,-32768,32767,1,1,S

6,IC,,,A,1.52E-04,0,0,-32768,32767,1,1,S

60

1

10000,4167

11/07/1995,08:15:22.000000

11/07/1995,08:15:22.100000

ASCII

1



*.Dat file

Sample # Samp. Time Va Vb Vc Ia Ib Ic

1 0 -1040 -27118 28883 63 -19673 27519

2 100 195 -27733 28279 110 -20038 26829

3 200 1430 -28308 27635 158 -20376 26101

4 300 2663 -28844 26952 205 -20684 25336

5 400 3892 -29338 26230 251 -20963 24534

6 500 5116 -29791 25471 298 -21212 23698

7 600 6332 -30201 24676 344 -21431 22828

8 700 7539 -30568 23846 389 -21620 21926

9 800 8736 -30892 22982 434 -21778 20993

10 900 9920 -31172 22086 479 -21905 20030

11 1000 11090 -31408 21158 522 -22000 19038

../../../comtrade/jayfile1.csv




Max and Min Values for Voltage



*.Dat file

Max value of sample Va = 32762Value of factor “a” & “b” : 0.0028633,0Va =aX + bVa = 0.0028633 * 32762 = 93.8074



Add or delete Channel

ComTrade File

31



Test ground fault protection

Needs Neutral current from Phase current recordings

ComTrade data : three phases of currents and voltages

Create additional channel for neutral current

In = Ia+Ib+Ic

Data manipulation : ComTrade



Neutral Current from 3 phase currents

Sample # Samp. Time Va Vb Vc Ia Ib Ic In=Ia+Ib+Ic

1 0 -1040 -27118 28883 63 -19673 27519

2 100 195 -27733 28279 110 -20038 26829

3 200 1430 -28308 27635 158 -20376 26101

4 300 2663 -28844 26952 205 -20684 25336

5 400 3892 -29338 26230 251 -20963 24534

6 500 5116 -29791 25471 298 -21212 23698

7 600 6332 -30201 24676 344 -21431 22828

8 700 7539 -30568 23846 389 -21620 21926

9 800 8736 -30892 22982 434 -21778 20993

10 900 9920 -31172 22086 479 -21905 20030

11 1000 11090 -31408 21158 522 -22000 19038

12 1100 12244 -31599 20200 565 -22065 18019

13 1200 13381 -31745 19213 607 -22098 16975

14 1300 14499 -31846 18199 649 -22100 15906



Process : Calculating In

Convert Data Values to analog sample *. Dat

Get a & b values from *.cfg data

I = aX + b

Get all three phases analog samples

Add sample of phase currents for neutral current

Convert In to data value from analog sample values

Modify *.cfg data for additional channel



Process : Calculating In

I phase = aX+b

In = aX + bCalculate “X”, “a” &

“b”

In = Ia+Ib+Ic

*.DatX Values for each phase

*.Cfga & b Values

for each phase



*.DAT file with In



New *.cfg file



ComTrade file with calculated In



Comtrade data without In



Original File



Pre fault recording is too small

Data are of different durations from both ends of the line : End to End testing

Needs all phases from 2 ph & G recording

Simulate power system events based on protection response

Voltages & Currents scaling for the test

Data Manipulation : Applications



ComTrade Data for Simple RTDS



ComTrade Data for simple RTDS

Pre Fault Fault Post Fault



CT/PT Ratio changed in the field and need to re-evaluate protection performance

Evaluate the protection response for the different values of the fault current

The current recorded is too high for the test instrument

Easy to do it by manipulating *.cfg file

Example shows change of CT ratio by 10

Data Scaling : Why and How



Data Scaling for Testing and Evaluation



• Changed CT ratio from 1:1 to 10:1

• Changed “S” to “P”

• Save the *.cfg file with new name

• *.dat file remains intact but save with the new name

Working with *.cfg file



Data Scaling for Testing and Evaluation


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• Universally accepted standard : IEC and IEEE duel logo

• One of the Smart Grid Standard where interoperability is

used for over 20 years

• ComTrade Data structure is simple

• *.dat and *.cfg should have same name & defined format

• *.dat can be in ASCII or Binary format

• Y = aX + b is the only formula need to be understood

• Extremely useful tool for protection engineers

Conclusion


Questions?

49

comtrade file manipulationver1

Engineering

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comtrade recorddata

datconfiguration file

cfgheader file

hdrinformation file

features comtrade data

comtrade standard structure