500 kV GIS盆式绝缘子故障原因分析与处理

Cause Analysis and Treatment of 500 kV GIS Basin Insulator Fault

简要介绍了一起500 kV GIS断路器故障过程及动作保护情况,将故障断路器返厂解体后发现断路器与两侧互感器之间的盆式绝缘子均有裂纹,其中左侧盆式绝缘子裂纹已导致局部放电。经对盆式绝缘子进行电气试验验证,排除了制造缺陷产生纹裂的可能,最终通过综合分析得知,其纹裂是安装时法兰螺栓力矩紧固不均匀引起盆式绝缘子受力不均所导致的。

This paper introduces the fault process and action protection of a 500 kV GIS circuit breaker.When the fault circuit breaker returns to the factory and disintegrates,it is found that there are cracks in the basin insulator between the circuit breaker and the mutual inductors on both sides.The cracks in the left basin insulator have caused partial discharge.Electrical test validation of the basin insulator eliminates the possibility of cracking caused by manufacturing defects.Through comprehensive analysis,it is known that the moment of flange bolt is not uniform during installation,resulting in cracking caused by uneven stress of the basin insulator.