基于积分面积的直流配网单极接地故障选线方法  

A Single-Pole Ground Fault Selection Method for DC Distribution Networks Based on Integral Area

作　　者：豆敏娜 田影 王毅钊 王晓卫 屈新宇 王雪[2] 岳阳 张志华 DOU Minna;TIAN Ying;WANG Yizhao;WANG Xiaowei;QU Xinyu;WANG Xue;YUE Yang;ZHANG Zhihua(State Grid Shaanxi Electric Power Research Institute,Xi’an710100,Shaanxi,China;School of Electrical Engineering,Xi’an University of Technology,Xi’an710054,Shaanxi,China)

机构地区：[1]国网陕西省电力有限公司电力科学研究院,陕西西安710100 [2]西安理工大学电气工程学院,陕西西安710054

出　　处：《电网与清洁能源》2025年第1期10-16,共7页Power System and Clean Energy

基　　金：国家自然科学基金项目(52177114,61403127);国网陕西省电力有限公司科技项目(5226KY220006,5226KY230001)。

摘　　要：在柔性直流配电系统中,因存在低惯性、弱阻尼特性,导致系统发生单极接地故障时系统故障电流大,且故障过程发展极快,对保护方案的快速性和可靠性提出了更高要求。分析直流配电网发生单极接地故障时的故障电流特征,并根据故障发生后健全馈线与故障馈线的正、负极电流在大小与方向之间存在的差异,提出一种基于积分面积的直流配网单极接地故障选线方法。在电磁暂态仿真软件(power systems computer aided design,PSCAD)上搭建基于模块化多电平换流器(modular multilevel converter,MMC)单端柔直配电网,验证所述方案的有效性。仿真结果表明:该选线方案能够快速、准确、可靠地识别线路;具有一定的耐受过渡电阻、不同数据窗的能力。The low inertia and weak damping characteristics existing in the flexible DC distribution system often lead to a large system fault current when the system has a unipolar ground fault,and the fault process develops rapidly,which puts forward higher requirements for the rapidity and reliability of the protection scheme.To solve this problem,this paper first analyzes the fault current characteristics of the DC distribution network in the event of a unipolar ground fault.Second,according to the difference between the magnitude and direction of the positive and negative currents of the sound feeder and the fault feeder after the fault occurs,a single-pole ground fault selection method based on the integration area of the DC distribution network is proposed.A single-ended flexible direct distribution network based on a modular multilevel converter(MMC)is built on the Power Systems Computer Aided Design,and finally the effectiveness of the proposed scheme is verified.The results show that the line selection scheme can identify the line quickly,accurately and reliably,and is able to withstand transition resistance and different data windows.

关 键 词：单极接地故障 直流配电网 故障选线 模块化多电平换流器 

分 类 号：TM77[电气工程—电力系统及自动化]