500 kV线路保护出口板接点故障分析与处理

Analysis and Treatment of 500 kV Line Protection Export Board Contact Fault

根据一次线路保护改造验收过程中发现的单相瞬时性故障下保护单跳单重失败的问题,介绍了一起500 kV变电站线路保护出口板接点故障的处理案例,阐述了缺陷发现及处理的全过程。从保护动作行为分析和二次回路检查分析两个角度排查故障点,排查结果表明缺陷是由A相、C相瞬时性故障时B相跳闸接点同步闭合导致的。最后,依据案例提出保护校验中流程和方法的进一步优化方案。案例可为相关人员处理类似事故提供参考,具有实际指导意义。

In the process of accepting primary line protection transformation,it was found that the protection failed in a single trip and multiple trips under single-phase instantaneous faults.The fault points were investigated from two perspectives:protection action behavior analysis and secondary loop inspection analysis.The troubleshooting results show that the defect is caused by the synchronous closure of the trip contact of phase B when the transient fault of phase A and phase C.Finally,further optimization of processes and methods in protection verification was proposed based on the case.The case can provide reference for relevant personnel to deal with similar accidents and has practical guidance.