高阻接地故障时消弧线圈并联小电阻接地的控制方法研究  

Study on the control method of high impedance faults in the neutral via arc suppression coil paralleled with a low resistance grounded system

作　　者：叶远波 汪胜和 谢民 蔡翔 徐波 魏立新[4] YE Yuanbo;WANG Shenghe;XIE Min;CAI Xiang;XU Bo;WEI Lixin(Anhui Electrical Power Dispatch Center,Hefei 230022,China;Shanghai Lanrui Electric Co.,Ltd.,Shanghai 201613,China;School of Electrical Engineering,Shanghai University of Electric Power,Shanghai 200090,China;Shanghai Sieyuan Electric Co.,Ltd.,Shanghai 201108,China)

机构地区：[1]安徽电力调度控制中心,安徽合肥230022 [2]上海蓝瑞电气有限公司,上海201613 [3]上海电力大学电气工程学院,上海200090 [4]上海思源电气股份有限公司,上海201108

出　　处：《电力系统保护与控制》2021年第19期181-186,共6页Power System Protection and Control

基　　金：国家电网公司科技项目资助(52120018004L)。

摘　　要：中性点经消弧线圈并联小电阻接地方式可以实现自动熄弧与永久接地故障的可靠保护,兼具中性点经消弧线圈接地和经小电阻接地两种方式的优点。但在高阻接地故障时投切并联小电阻可能造成零序电压低于保护装置启动阈值,从而造成保护装置误动,甚至可能加剧故障。为此,提出一种高阻接地故障时并联小电阻投入的控制方法。首先,利用电力系统的基本原理分析了高阻接地故障时并联小电阻投入前后零序电流与零序电压的特征。其次,根据故障线路与非故障线路零序电流与零序电压夹角的异同提出并联小电阻装置退出的判据,据此也提出一种线路故障的保护方法。最后通过仿真验证了所提方法的有效性。The neutral via arc suppression coil paralleled with a low resistance grounded system can realize arc extinguishing and reliable protection against permanent single-line-to-grounded faults, taking into account the advantages of resonant grounded systems and the neutral via a low resistance grounded system. However, in the case of high impedance faults, the paralleling low resistance may cause the zero sequence voltage to be lower than the starting threshold value of the protection device. This may cause the protection device to malfunction and even aggravate the fault.In this paper, a control method of the paralleling low resistance in the high impedance fault is proposed. First, the characteristics of zero sequence current and the zero sequence voltage before and after the paralleling low resistance is put into operation are analyzed, which is based on the power system basic principle. Secondly, from the difference between the angle of the zero sequence current and the zero sequence voltage of the fault line and the non-fault line, the criterion of the paralleling low resistance device exit is proposed. Finally, the effectiveness of the method is verified by simulation.

关 键 词：消弧线圈 并联小电阻 高阻故障 单相接地故障 

分 类 号：TM862[电气工程—高电压与绝缘技术]