二次寄生回路引发500 kV断路器跳闸事故分析

Analysis of 500 kV Circuit Breaker Trip Caused by Secondary Parasitic Circuit

2019年某月某日,某发电厂发变组保护传动工作需要,申请调度发变组出口断路器5022、5023开关停电,2台开关全部转冷备用,断开5022开关操作电源后,线路侧断路器5021开关跳闸。经核实,线路侧开关跳闸的主要原因是因为3台断路器保护柜存在寄生回路。文章对整个事件进行总结分析,对以后的变电站项目投运操作有着非常重要的指导意义。

On a certain day in 2019,for the protection and transmission work of the generator transformer unit in a power plant,it applied for dispatching the outlet breakers 5022 and 5023 of the generator transformer unit to cut off the power supply,and the two switches were all turned into cold standby.After the operation power of 5022 switch was cut off,the circuit breaker 5021 at the line side tripped.It is verifi ed that the main reason for the trip of the switch on the line side is due to the parasitic circuit in the three breaker protection cabinets.This paper summarizes and analyzes the whole event,which has a very important guiding significance for the operation of the substation project in the future.