开关跳闸时间延迟引发的保护动作故障分析

针对一起水电厂一连串保护动作跳闸故障进行波形、数据分析及试验,最终确定了故障跳闸原因为110 kV断路器机构卡涩、跳闸时间超标、动作延迟造成该站220 kV 1号、2号、3号主变后备保护动作、备自投保护动作,机组事故停机,后采取了对断路器机构进行维保、分合闸挚子进行清洗、更换润滑脂等措施,保证了开关的正常运行。

Analysis of Protection Action Fault Caused by Switch Trip Time Delay

Based on the waveform, data analysis and test of a series of protection action tripping faults in a hydropower plant, it is finally determined that the cause of the tripping fault is the stuck of 110 kV circuit breaker mechanism, which causes tripping time exceeding the limit, then the action delay leads to the backup protection actions of No.1, No.2 and No.3 220 kV main transformers, the backup automatic switching protection actions and unit shutdown. The measures such as maintenance of breaker mechanism, cleaning of switches and changing grease are taken to ensure the normal operation of the switches.