35kV户外真空断路器绝缘击穿故障分析及处理

为查找35 kV户外真空断路器绝缘击穿故障原因,对ZW7-40.5型真空断路器进行了交流耐压、瓷套绝缘电阻试验。分析了该型号的断路器外绝缘采用真空绝缘脂,此绝缘脂属于液体绝缘介质,设备在运行及安装过程中,会增加液体介质水分含量,易导致绝缘击穿引起设备故障。通过分析交流耐压试验数据,找到了绝缘击穿故障部位。介绍了绝缘击穿事故处理的查找方法,提出了避免断路器击穿的防范措施。

Analysis and Treatment of Insulation Breakdown Fault of 35 kV Outdoor Vacuum Breaker

In order to find out the reason of insulation breakdown fault of 35 kV outdoor vacuum breaker,the AC withstand voltage test and the insulation resistance of porcelain bushing test were done for the ZW7-40.5 type vacuum breaker.It is analyzed that the outside insulation of such type breaker is vacuum insulation grease which belongs to liquid insulation medium,and the process of operation and installation will increase the water content of the liquid medium which will easily lead to the breakdown of insulation and the fault of the breaker.The position of insulation breakdown was found based on the data of AC withstand voltage test.The find method in the insulation breakdown fault treatment process is introduced and measures to prevent the insulation breakdown of the breaker are proposed.