户内绝缘子污秽闪络分析及改善建议

Analysis and Improvement Measures of Polluted Insulator Flashover Indoor

绝缘子污秽闪络会严重威胁电网的安全运行。针对市区内大量老旧变电站,因负荷重要、接线复杂、改造困难、支柱绝缘子爬电比距难调整、目前无法退出运行等原因,介绍了绝缘子污闪形成的原因、必要条件及机理,结合220kV武威站户内35kV正Ⅱ母6号电容器因事故引发跳闸案例分析,得出污闪跳闸的主要原因是站内空气湿度陡然增加,致使绝缘子表面在工作电压的作用下产生泄漏电流,最终酿成跳闸事故。依据变电站环境气候的不同,从运维方面入手,对支柱绝缘子防污闪工作,提出了在湿润和干燥环境下改善绝缘子闪络的措施与建议。

The polluted insulator flashover is a risk of power grid＇s safety. There are amounts of transformer substations in city center, which have important load, complex connection mode and difficult to reform. Creep- age distance is also hard to adjust and can not be quit. This paper indicate the factor and condition of polluted insulator flashover. Presented an example of 220 kV Wuwei station. The main cause o{ this accident is the suddenly addition of air humidity which lead to leakage current of the surface. In point of view of operation worker, the measures to avoid flashover in diferrent condition are proposed.