一起GIS设备漏气及现场交流耐压试验击穿故障分析

A Case of Insulated Swithgear Equipment Air Leakage and Site AC Withstand Voltage Test Breakdown Fault Analysis

针对某220 kV变电站66 kV气体绝缘金属封闭组合电器(GIS)因盆式绝缘子出现裂痕发生漏气事件,介绍了设备漏气故障点发现过程,解体处理后进行主回路绝缘试验过程中出现击穿现象,通过闪络定位仪准确定位到击穿气室,再次解体发现导电座上有明显的磕碰痕迹,改变了导电座周围的空间电场分布,导致在耐压过程中导电座下侧局部电场发生畸变,耐压过程中最终在绝缘子表面发生了沿面闪络放电。试验验证了闪络定位仪在闪络故障检测及故障点定位应用中的准确性和有效性,可在高压设备交接试验中推广。

In allusion to the leakage event of basin-type insulator cracks in the66kV gas insulated switchgear(GIS)in the220kV substation,introduction was made to the discovery process of equipment air leakage fault points and the punchthrough in the process of major loop insulation test after disintegration disposal.The flashover position indicator was used to carry out accurate positioning to the breakdown air chamber.There were obvious signs of bumps on the conductive seat,which changed the space electric field around the conductive seats and caused electric field distortion in the process of withstand voltage downside the conductive seat.In the process of withstand voltage the flashover discharged along surface of the insulators finally.The test verifies the accuracy and validity of the flashover position indicator applied in the flashover faults testing and positioning.