一起利用录波数据分析继电保护寄生回路的案例

Analysis of Parasitic Circuit of Relay Protection Based on Fault Recording Data

对一起220kV线路单相永久性故障进行原因分析。虽然双套保护装置均正确动作并且跳闸成功,但是对现场相关保护录波进行分析发现,2号保护装置开关量存疑。通过排查,发现该保护存在隐藏的寄生回路,即同时接入了操作箱TWJ接点和断路器位置接点,进而导致了开关量录波的变化。

As one 220 kV line single-phase fault occurred,both line protection relays acted correctly.The No.2 line protection input is in doubt based on the analysis of fault recording data.Through professional checking,it is found that there is a hidden parasitic circuit in protection relay.The reason is that TWJ contacts and circuit breaker location contacts access to device at the same time.