基于多重综合判据的单端MMC直流配电网单极接地保护方法  

Single Pole Grounding Protection Method for Single-ended MMC DC Distribution Network Based on Multiple Comprehensive Criteria

作　　者：张伟 方永丽[2] 孙硕 姜华 曹亚非 沈兴来 ZHANG Wei;FANG Yongli;SUN Shuo;JIANG Hua;CAO Yafei;SHEN Xinglai(Nanjing Power Supply Branch of State Grid Jiangsu Electric Power Co.,Ltd.,Nanjing,Jiangsu 210008,China;School of Electrical Engineering,China University of Mining and Technology,Xuzhou,Jiangsu 221116,China;Xuzhou Power Supply Branch of State Grid Jiangsu Electric Power Co.,Ltd.,Xuzhou,Jiangsu 221000,China)

机构地区：[1]国网江苏省电力有限公司南京供电分公司,江苏南京210008 [2]中国矿业大学电气工程学院,江苏徐州221116 [3]国网江苏省电力有限公司徐州供电分公司,江苏徐州221000

出　　处：《广东电力》2022年第5期53-59,共7页Guangdong Electric Power

基　　金：国家电网有限公司科技项目(SGJSXZ00KJJS2001512)。

摘　　要：针对模块化多电平换流器(modular multilevel converter,MMC)直流配电网发生单极接地故障时,故障特征量小、故障线路与非故障线路故障特征区别不明显、干扰因素多、保护准确性较低等问题,提出一种基于多重综合判据的单端MMC直流配电网单极接地保护方法。首先计算各线路正负极电流之间的相似性故障判据、本线路与其他线路故障极电流之间的相似性故障判据、本线路与其他线路正负极电流和之间的相似性故障判据,然后综合这3种判据,构建基于多重综合判据的单极接地保护方法。在实时数字仿真系统(real time digital simulation system,RTDS)软件中搭建仿真模型进行验证,结果表明所提方法可以减少干扰因素的影响,具有较高的准确性和可靠性。Aiming at the problems of small amount of fault characteristics,no obvious differences between fault lines and non-fault lines,many affected factors and low protection accuracy when single pole grounding fault occurs in modular multilevel converter(MMC)DC distribution network,this paper proposes a single pole grounding protection method for single-ended MMC DC distribution network based on multiple comprehensive criteria.It firstly calculates the similarity fault criterion of the positive and negative currents of each line,the similarity fault criterion of the fault pole current of this line and other lines,and the similarity fault criterion of the sum of the positive and negative currents of this line and other lines.According to these three criteria,it constructs a single pole grounding protection method based on multiple comprehensive criteria.By establishing a simulation model in the real time digital simulation system(RTDS),the paper verifies that this method can reduce the influence of the affected factors and has higher accuracy and reliability.

关 键 词：MMC直流配电网 单极接地 综合判据 故障极 

分 类 号：TM721.1[电气工程—电力系统及自动化]