基于FTU的新型配电网单相接地故障研究  

Research on Single Phase Ground Fault of New Distribution Network Based on FTU

作　　者：刘红政 左毅 王伦 熊平 LIU Hongzheng;ZUO Yi;WANG Lun;XIONG Ping(State Grid Dawu County Power Supply Company,Hubei Xiaogan 432800,China;State Grid Hubei Electric Power Research Institute,Wuhan 430015,China)

机构地区：[1]国网大悟县供电公司,湖北孝感432800 [2]国网湖北省电力公司电力科学研究院,武汉430015

出　　处：《电力电容器与无功补偿》2024年第6期76-82,共7页Power Capacitor & Reactive Power Compensation

基　　金：国家电网公司科技项目(5400-202122573A-0-5-SF)。

摘　　要：新型配电网的10 kV线路装有大量的智能开关(FTU),当线路发生单相接地故障后,FTU可以快速监测零序电压电流电气量。分析故障线路、故障区段的零序电压电流的相位关系,与非故障线路和区段零序电压电流相位进行比较,可以快速选线和区段定位。本文针对两侧均含有FTU的故障区段进行零序网络分析,列写节点电压方程,可得出故障距离与两端零序电压电流的解析公式,该公式求出来的故障距离不受接地电阻影响,计算的故障距离较为准确。通过仿真分析,验证了新型配电网下利用零序电压电流进行单相接地故障选线、定位、测距的有效性,最后给出新型配电网单相接地故障处置流程图,可为实际单相接地故障提供参考。The 10 kV line of new distribution network is equipped with a large number of intelligent switches(FTU).The FTU,in case of a singlephase ground fault on the line,can quickly monitor the zerosequence voltage and current electrical volume.The phase relationship of zero sequence voltage and current of faulty line and section is analyzed and compared with that of non fault line and section,which can quickly select line and section positioning.In this paper,zerosequence network analysis for faulty sections containing FTUs on both sides is made,the node voltage equation is written so that the analytical formula of the fault distance and the zerosequence voltage current on both ends can be obtained.The fault distance obtained by the formula is free from the influence of ground resistance and the calculated fault distance is more accurate.Through simulation and analysis,the effectiveness of singlephase grounding fault line selection,location and distance measurement by using zerosequence voltage current under the new type of distribution network is verified.Finally,the handling flow chart of single phase ground fault of new type of distribution network is given,which can provide reference for actual singlephase grounding faults.

关 键 词：新型配电网 FTU 单相接地故障 零序网络 故障定位测距 零序电压电流 

分 类 号：TM862[电气工程—高电压与绝缘技术]