消弧线圈未停用造成10 kV母线失电事故分析  

Analysis of Power Loss Accident of 10 kV Bus Caused by Non Shutdown of Arc Suppression Coil

作　　者：董济康 DONG Jikang(State Grid Shandong Tancheng Power Supply Company,Shandong Tancheng 276100,China)

机构地区：[1]国网山东郯城县供电公司,山东郯城276100

出　　处：《农村电气化》2022年第5期35-36,共2页Rural Electrification

摘　　要：10 kV线路零序保护是线路发生非对称接地故障时的一种保护,当线路发生非对称接地故障时,零序TA感应到故障零序电流,开关进而保护动作跳闸。若接地变消弧线圈投入,产生的感性电流会补偿故障点的容性电流,导致线路故障点零序电流降低,达不到保护定值,而接地变中流过的零序电流将会引起接地变零序保护动作越级跳闸。所以线路零序保护投入时,应将消弧线圈退出,保证存在故障点的线路直接感受到故障电流而出口跳闸。10 kV line zero sequence protection is a kind of protection in case of asymmetric grounding fault.When the line has asymmetric grounding fault,the zero sequence CT senses the fault zero sequence current,and then the switch acts and trips.If the arc suppression coil of the grounding transformer is put into operation,the inductive current generated will compensate the capacitive current at the fault point,resulting in the reduction of the zero sequence current at the line fault point and the failure to reach the protection setting value.The zero sequence current flowing through the grounding transformer will cause the zero sequence protection action of the grounding transformer to skip the level.Therefore,when the line zero sequence protection is put into operation,the arc suppression coil shall be withdrawn to ensure that the line with fault point can directly feel the fault current and trip at the outlet.

关 键 词：零序保护 消弧线圈 容性电流 补偿 

分 类 号：TM475[电气工程—电器]