一起隔离开关机构失效引起的GIS绝缘故障分析

Insulation Fault Analysis of GIS Caused by the Failure of Operating Mechanism of Disconnector

GIS设备由于其封闭性,难以直观的确认其隔离开关和接地开关的位置状态,通常通过操动机构上的指示牌和辅助开关发出的二次分合闸信号来判断其内部刀闸是否分、合闸到位。一旦分合闸指示牌和辅助开关位置信号出现误差,影响对分合闸状态的判断,会引起GIS内部的绝缘故障。文中结合一起220 kV GIS隔离开关因机构位置判断失效引起的内部闪络击穿故障,分析故障的根本原因,并提出了解决和预防方案,提高了该型GIS设备的运行可靠性。

The position and state of disconnector and earthing switch in GIS are not visually confirmed due to the en⁃closed feature of GIS equipment.The opening and closing of the internal blades in their place are judged by the indi⁃cation board on the operating mechanism and the secondary opening signal which is issued by the auxiliary switch.Once the opening and closing indicator and the position signal of the auxiliary switch have error,the judgment on the opening and closing condition can be affected and the insulation fault inside GIS can be caused.In this paper,the root cause of internal flashover breakdown fault is analyzed in combination of the flashover breakdown fault due to faulty judgement of operating mechanism of 220 kV GIS disconnector.The solution and prevention proposal are pro⁃posed so to improve operation reliability of the GIS equipment.