직류옵셋제거필터에 의한 거리계전기법의 성능 개선에 관한 연구

• Published in: 전기학회 논문지 P권, 64(2) Vol. 64P; no. 2; pp. 67 - 73
• Main Authors: 이경민(Kyung-Min Lee), 박유영(Yu-Yeong Park), 박철원(Chul-Won Park)
• Format: Journal Article
• Language: Korean
• Published: 대한전기학회 2015
• Subjects: 전기공학; DFT; Transmission line; Line impedance; Residual current; ATP; DC offset elimination filter; Distance relay
• ISSN: 1229-800X; 2586-7792

Distance relay is widely used for the protection of long transmission line. Most of distance relay used to calculate line impedance by measuring voltage and current using DFT. So if there is a computation error due to the influence of phasor by DC offset component, due to excessive vibration by measuring line impedance, overreach or underreach can be occurs, and then abnormal and non-operation of distance relay can be issue. It is very important to implement the robust distance relaying that is not affected by DC offset component. This paper describes an enhanced distance relaying based on the DC offset elimination filter to minimize the effects of DC offset on a long transmission line. The proposed DC offset elimination filter has not need any prior information. The phase angle delay of the proposed DC offset filter did not occurred and the gain error was not found. The enhanced distance relay uses fault current as well as residual current. The behavior of the proposed distance relaying using off-line simulation has been verified using data about several fault conditions generated by the ATP simulation software.