| 摘要 |
PURPOSE:To continue transmission of power through sound three-phases in adjacent line, if any, upon occurrence of permanent mulltiple fault in parallel double transmission lines wherein the fault sustains even after execution of reclosing. CONSTITUTION:In the reclosing system for transmission line protective relay unit which recloses on condition that a linkage with the counterpart end exists upon occurrence of multiple fault on a power system comprising two parallel transmission lines, a linkage confirming unit 11 detects presence of sound three- phases in two parallel transmission lines during fault immediately after reclosing. On the other hand, when a counter 8 and a trip time decision circuit 9 detects that the fault sustains after reclosing to cause trip again, interruption of remaining phases and open-phase interruption of circuit breaker are blocked. |
