一起110 kV气体绝缘电流互感器放电事故分析

Analysis on A 110 kV GIS Current Transformer Dischage Accident

针对一起运行中的110 kV气体绝缘电流互感器放电事故,通过外观检查、电气试验、气体检测、解体分析、相间比对等方法,结合故障时运行工况、站内操作、天气情况等因素,综合判断事故原因是极寒天气等外部因素影响下气体密度继电器气管回路金属部件发生形变而出现漏气现象,电流互感器内部气压在短时间内下降使得内部高、低电场间绝缘降低,进而导致气隙绝缘击穿。并针对同类型设备安全运维、新设备验收和设备选型等工作提出建议措施。

With view of the factors such as the operation condition under fault,operation,weather and others,the cause of a 110 kV GIS current transformer discharge accident is analyzed by using methods such as observational check,electric test,gas detection,disintegration analysis,phase comparsion and others.The analysis shows that the gas pipe circuit metal parts of the gas density relay produces deformation under very cold weather and other factors and result in the gas leakage,the sharp fall of inner pressure of the current transformer in short time,the reduction of the insulation betwwen the inner high and low electric fields and finally the gas gap insulation breakdown.Suggeastions are given also for selection,acceptance,operation maintenance of the same type equipments.