一起电压互感器二次回路接地事故的分析及启示

Analysis and revelation of an accident due to the voltage transformer secondary circuit grounding

某变电站发生一起110kV副母C相电压互感器二次线圈接地的事故,该事故最终引起110kV副母压变空开、正母压变空开相继跳闸,110kV副母压变隔离开关的误分闸。本文详细分析了此次事故的原因及发展的过程,并提出了对电压回路N600接线的改进方法,以求降低类似事件的影响范围。

One accident of an 110kV auxiliary bus phase C voltage transformer secondary circuit grounding in a substation is occurred,which causes the air switches of the two bus voltage transformers tripping one after another, and the isolator of llOkV auxiliary bus voltage transformer is falsely opened in addition.This paper detailed analyses the reasons and processes of the accident,an improved wiring method of the voltage circuit N600 is proposed, which will minimize the influence of the relevant accident.