Browse > Article

A Busbar Current Differential Relay with a Compensating Algorithm  

강용철 (전북대 전자정보공학부)
윤재성 (전북대 전자정보공학부)
Publication Information
The Transactions of the Korean Institute of Electrical Engineers A / v.53, no.4, 2004 , pp. 214-220 More about this Journal
Abstract
This paper describes a busbar current differential relay in conjunction with a current transformer(CT) compensating algorithm irrespective of the level of the remanent flux. The compensating algorithm detects the start of first saturation if the third-difference function of the current exceeds the threshold; it estimates the core flux at the first saturation start by inserting the negative value of the third-difference function of the current into the magnetization curve; thereafter, it calculates the core flux during the fault and compensates the distorted current using the magnetization curve. The algorithm estimates the correct secondary current irrespective of the level of the remanent flux and needs no saturation point of the magnetization curve. The proposed relay can improve not only security of the relay on an external fault with CT saturation but sensitivity of the relay on an internal fault; the relay can improve the operating speed on n internal fault with CT saturation. This paper concludes by implementing the relay into a digital signal processor based prototype relay.
Keywords
Current differential relay; Saturation, Compensation; Remanent flux; Third-difference function;
Citations & Related Records
Times Cited By KSCI : 3  (Citation Analysis)
연도 인용수 순위
1 A. Kumar and P. Hansen, 'Digital bus-zone protection,' IEEE Computer Applications in Power, vol. 6, no. 4, Oct. 1993, pp. 29-34   DOI   ScienceOn
2 강용철, 윤재성, 김동룡, '변류기 전류보상 알고리즘을 이용한 모선보호용 전류 차동계전 알고리즘,' 전기학회 논문지 A, 제49권 제9호, 2000년 9월, pp. 446-450   과학기술학회마을
3 강용철, 윤재성, 강상희, '개선된 변류기 전류보상 알고리즘을 적용한 모선보호용 비율전류차동 계전방식,' 전기학회 논문지 A, 제52권 제3호, 2003년 3월, pp. 158-164
4 강용철, 임의재, '개선된 변류기 2차 전류보상 알고리즘,' 전기학회 논문지 A, 제52권 제7호, 2003년 7월, pp. 387-392
5 L. F. Kennedy and C. D. Hayward, 'Harmonic-Current-Restrained Relays for Differential Protection,' AIEE Trans. vol. 57, 1938, pp. 262-266
6 J. B. Royle and A. Hill, 'Low Impedance Based Differential Busbar Protection for Application to Busbars of Widely Differing Configuration,' IEE Fourth International Conference on Developments in Power System Protection, Apr. 1989. pp. 40-43
7 F. Andow, N. Suga, Y. Murakamy, and K. inamura, 'Microprocessor-based busbar protection relay,' IEE Fifth International Conference on Developments in Power System Protection, Mar. 1993. pp. 103-106