基于2组母联电流互感器的死区保护

Dead zone protection with dual busbar-tie current transformers

带母联接线方式的母线保护中存在死区,常规的微机母线保护是靠先后切除2段母线上的所有连接元件来解决该问题,但多跳了1条健全母线。对此,提出通过引进2组母联电流互感器(TA)并适当对死区保护进行2种改进:一是把2组母联TA 2路电流做成1个母联小差保护;二是仍采用常规的2组TA交叉接法,但对保护流程作一些修改。

There is a dead zone in busbar protection with busbar-tie. Its traditional solution is to cut off all elements connected with two busbars,causing the healthy busbar out-of-work. A scheme with dual busbar-tie CTs（Current Transformers） is presented. It improves the dead zone protection in two ways：using currents of dual busbar- tie CTs to form a busbar- tie differential protection; modifying the protection flow while keeping regular cross connection for the dual CTs.