500kV紧凑型线路相间间隔棒闪络原因分析

The Flashover Analysis on the Phase Spacer of 500kV Compact Transmission Line

输电线路相间间隔棒是预防导线舞动的重要机械构件,其运行状态直接影响电网的安全可靠性。为探究500 kV某线路相间间隔棒闪络故障的原因,首先分析了爬电距离、憎水性、盐密等外部性能,并在实验室条件下对故障间隔棒进行升压试验,利用红外、紫外测试仪观察温升和放电现象。通过综合对比干燥、湿润条件下和去除盐密前后的间隔棒爬电过程及闪络情况,分析认为积污量较高和爬电比距不足导致的污闪是本次相间间隔棒闪络故障的主要原因。研究结果可为紧凑型输电线路相间间隔棒的运行维护提供一定的参考。

Interphase spacers of transmission lines are important mechanical components to prevent line galloping,whose operation status directly affect the safety and reliability of the power grid.In order to find out the cause of the flashover breakdown of the phase spacer on a 500 kV transmission line,the external properties including creepage distance,hydrophobicity and salt density were firstly analyzed;then the fault spacer was subjected to a voltage boosting test under laboratory conditions,where infrared and ultraviolet detectors were applied to observe the temperature rise and discharge phenomenon.By comparing the creepage and flashover status of the spacer under dry and humid conditions as well as before and after removing the salt density comprehensively,it is concluded that the pollution flashover resulted from the high pollution accumulation and the short of unified specific creepage distance is the main cause of the breakdown of the interphase spacer.The results of this research could provide certain reference for the operation and maintenance of the interphase spacers used in compact transmission lines.