LW30A-550型罐式断路器故障缺陷分析与处理

Fault Analysis and Treatment of LW30A-550 Tank Circuit Breaker

针对某500 kV变电站断路器灭弧室屏蔽罩放电击穿并且损毁严重的问题,对故障原因进行分析,并进行理论仿真计算和现场试验验证,得出此次内部绝缘击穿放电的原因是灭弧室屏蔽罩顶端均压环卷口中铁屑杂质和金属颗粒未及时清理干净。最后提出加强装配过程管控、改变罐体侧盖板拆除工序等一系列整改措施。

Aiming at the problem of electric breakdown and serious damage to the shielding cover of arc extinguishing chamber of circuit breaker in a 500 kV substation.The fault causes are analyzed,and the theoretical simulation calculation and field test verification are carried out.The reason of the internal insulation breakdown discharge is that the iron dust impurities and metal particles in the winding mouth of the grading ring at the top of the shielding cover of the arc extinguishing chamber are not cleaned up in time.Finally,a series of improvement measures are proposed,such as strengthening the assembly process control,changing the removal process of tank side cover plate.