Oleg BAGLEYBTER

Implementation of a current transformer model in Simulink® based on Jiles-Atherton theory of

hysteresis

GRID

CIGRE 2013 Yekaterinburg

Existing CT models – PSCAD, RTDS

Disadvantage:

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Disadvantage:

The built-in burden and leads do not allow creating complex protection schemes

Creating CT model in MATLAB/SIMULINK

Main drivers:

1. More flexibility with external burden connection to model complex CT arrangements

II −

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BAII −

2. Integrated development and testing of protection algorithms in SIMULINK environment

Mathematical model: well-established Jiles-Atherton theory of electromagnetic hysteresis, parameters identical to RTDS and PSCAD models

CT model algorithm based on Jiles-Atherton hysteresis theory

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© ALSTOM 2010. All rights reserved. Information contained in this document is provided without liability for information purposes only and is subject to change without notice. No representation or warranty is given or to be implied as to the completeness of information or fitness for any particular purpose. Reproduction, use or disclosure to third parties, without express written authority, is strictly prohibited.

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CT model in SIMULINK

© ALSTOM 2010. All rights reserved. Information contained in this document is provided without liability for information purposes only and is subject to change without notice. No representation or warranty is given or to be implied as to the completeness of information or fitness for any particular purpose. Reproduction, use or disclosure to third parties, without express written authority, is strictly prohibited.

Three separate CT models developed:

Advanced settings CT model:

Settings identical to PSCAD and RTDS models (18 parameters in total)

Simple settings CT model:

Only 5 parameters: knee-point voltage and

© ALSTOM 2010. All rights reserved. Information contained in this document is provided without liability for information purposes only and is subject to change without notice. No representation or warranty is given or to be implied as to the completeness of information or fitness for any particular purpose. Reproduction, use or disclosure to third parties, without express written authority, is strictly prohibited.

Only 5 parameters: knee-point voltage and current, pri/sec ratio, secondary resistance, remnant flux

Air-gapped CT model:

EXPERIMENTAL (has not been tested against real physical CTs)

Application examples:1. Building complex CT schemes

BAII −

0.66 seconds of real time per 1 second of simulation

© ALSTOM 2010. All rights reserved. Information contained in this document is provided without liability for information purposes only and is subject to change without notice. No representation or warranty is given or to be implied as to the completeness of information or fitness for any particular purpose. Reproduction, use or disclosure to third parties, without express written authority, is strictly prohibited.

Application examples:2. Studying the Saturation phenomenon

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Application examples:3. Transient Biasing in Current Differential

..THRDIFFI

DIFFI

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..THRDIFFI

DIFFI

BIASTRI .

Application examples:4. Provisional CT requirements testing in SIMULINK

In order to test the

Linear search of RLIM

for specified combinations of If, X/R, fault type, POW

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In order to test the protection with different CT remanence values every fault is applied six times: three times with a positive DC component and three times with a negative DC component.

Application examples:5. Subcycle Current Differential protection

Estimated reduction of the development time through

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RTDS test results:

Subcycle operation 17ms for fault currents If > 2*InomPatent pending

Estimated reduction of the development time through the use the SIMULINK CT models: 6 man-weeks

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