기동부하가 반영된 직류철도 시스템에서 보호계전기의 동작

초록

DC traction power system is operated ungrounded so that minimize the stray current. Because the stray current is still present, a rail potential is increased. The ground faults in the DC railway systems are usually detected by a potential relay(64P). And the fault current can be smaller than the current of load starting. So it's important to discriminate between the small fault current and the load starting current. The DC fault selective relay(50F) detects a remote short circuit fault. This paper analyzed behaviors of the potential relay(64P) and the DC fault selective relay(50F) using the load starting model in PSCAD/EMTDC.