The Transactions of the Korean Institute of Electrical Engineers A (대한전기학회논문지:전력기술부문A)

The Korean Institute of Electrical Engineers (대한전기학회)
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A Percentage Current Differential Relaying Algorithm for Bus Protection Using an Advanced Compensating Algorithm of the CTs

개선된 변류기 보상알고리즘을 적용한 모선보호용 비율전류차동 계전방식

  • Published : 2003.03.01
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Abstract

This paper proposes a percentage current differential relaying algorithm for bus protection using an advanced compensating algorithm of the secondary current of current transformers (CTs). The compensating algorithm estimates the core flux at the start of the first saturation based on the value of the second-difference of the secondary current. Then, it calculates the core flux and compensates distorted currents using the magnetization curve. The algorithm Is unaffected by a remanent flux. The simulation results indicate that the proposed algorithm can discriminate internal faults from external faults when the CT saturates. This paper concludes by implementing the algorithm into a TMS320C6701 digital signal processor. The results of hardware implementation are also satisfactory. The proposed algorithm can improve not only stability of the relay in the case of an external fault but sensitivity of the relay in the case of an internal fault.

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References

  1. F. Andow, N. Suga, Y. Murakamy, adn K. Inamura, 'Microprocessor-based busbar protection relay'. in IEE Fifth International Conference on Developments in Power System Protection, Mar. 1993
  2. A. Kumar and P. Hansen, 'Digital bus-zone protection', IEEE Computer Applications in Power. Vol. 6, No. 4, Oct. 1993, pp.29-34 https://doi.org/10.1109/67.238202
  3. M.S. Sachdev, T.S. Sidhu, H.S. Gill, 'A busbar protection technique and its performance during CT saturation and CT ratio-mismatch', IEEE Trans. on PWRD, Vol. 15, No. 3, July 2000, pp.895-901 https://doi.org/10.1109/61.871349
  4. C. Fernandez, 'An Impedance-Based CT Saturation Detection Algorithm for Bus-Bar Differential Protection', IEEE Trans. on PWRD, Vol. 16, No. 4, October 2001, pp.468-472 https://doi.org/10.1109/61.956722
  5. 강용철, 윤재성, 김동룡, '변류기 전류보상 알고리즘을 이용한 모선보호용 전류 차동계전 알고리즘', 전기학회논문지 A, 제49권 제9호, 2000년 9월, pp.446-450
  6. Y. C. Kang, S. H. Ok, S. H. Kang, 'A Novel CT Saturation Detecting Algorithm Unaffected by a Remanent Flux', IEEE PES 2001 SM, July 15-19, 2001, Vancouver, BC, Canada https://doi.org/10.1109/PESS.2001.970268