500kV变电站隔离开关分合闸不到位抢弧故障分析

Analysis on Arcing Fault of Divide-shut Brake Lacking of Isolation Switch in 500kV Substation

为了解决500 kV变电站隔离开关分合闸不到位抢弧故障的问题,结合阳江500 kV变电站隔离开关操作时所出现的故障问题,介绍了该故障的基本情况,并对故障原因进行了初步分析,认为开关操作所产生的暂态电磁干扰是导致隔离开关分合闸不到位的原因。在此基础上,从理论上对故障的机理进行分析,并对变电站二次侧暂态过电压进行现场测量,得出电磁干扰主要是通过高频电流互感器耦合到二次回路;再根据故障机理分析和现场测量提出利用在二次回路加装电涌保护器来解决该类问题。

In order to solve problem of arcing fault of divide-shut brake lacking of isolation switch in 500 kV substation,this paper introduces basic information of this fault by combining fault of isolation switch operation in Yangjiang 500 kV substa-tion and analyzes reason for the fault which is considered to be transient electromagnetic interference produced in switch op-eration. On the basis of analysis,fault mechanism was analyzed from angle of theory. Field measuring on transient overvolt-age at secondary side of the substation was conducted and conclusion was that electromagnetic interference was coupled sec-ondary circuit via high frequency current transformer. According to fault mechanism analysis and field measuring,method for solving this kind of problem was proposed which was to install surge protection device in secondary circuit.