가공송전선로와 지중송전선로가 연계된 혼합송전선로에서 디지털 거리계전 알고리즘

A Digital Distance Relaying Algorithm in Combined Transmission Line Connected whth Overhead Line and Underground Cable

This paper describes the digital distance algorithm in case of combined transmission line connected with overhead line and underground cable. Actually as fault is occurred in cable, it results in the complicated phenomena due to the several kind of grounding method in the sheath of cable. Accordingly the impedance. Therefore the correct impedance calculation algorithm is requested in combined transmission line to avoid the wrong trip of relay. This paper presents the development result of impedance calculation algorithm In such transmission line.