基于模块化多电平换流器的直流配电网接地方式选择  

Selection of Grounding Mode of DC Distribution Networks Based Modular Multi-level Converter

作　　者：王璐瑶 詹昕 高仁栋 曹骁勇 吴在军[1] WANG Luyao;ZHAN Xin;GAO Rendong;CAO Xiaoyong;WU Zaijun(School of Electrical Engineering,Southeast University,Nanjing 210096,China;State Grid Yangzhou Power Supply Company,Yangzhou 225009,China;State Grid Fuzhou Power Supply Company,Fuzhou 350000,China)

机构地区：[1]东南大学电气工程学院,江苏南京210096 [2]国网江苏省电力有限公司扬州供电公司,江苏扬州225009 [3]国网福建省电力有限公司福州供电公司,福建福州350000

出　　处：《供用电》2020年第5期2-10,共9页Distribution & Utilization

基　　金：国家重点研发计划资助项目(2018YFB0904700);国网江苏省电力有限公司科技项目“直流配用电系统过电压机理及防护研究”(J2019043)。

摘　　要：合理的接地方式是构建安全、可靠、高效直流配电系统的重要保障。针对基于模块化多电平(modular multi-level converter,MMC)换流器的直流配电网,首先介绍了其网络拓扑结构及组成,接着按交、直流侧接地点提出了3种典型的接地方案,并重点分析了不同接地方式对交流侧变压器阀侧单相接地故障、IGBT不闭锁情况下直流侧单极接地故障的影响,最后评估了交流侧联结变压器阀侧中性点接地作为MMC直流配电网接地方式的优势。研究结论为直流配电网的接地方式选择和保护配置提供了有益的参考。A reasonable grounding mode plays as an important guarantee for the safety,reliability and efficiency of the DC power distribution system.For the Modular Multi-level Converter(MMC) based DC distribution networks,the network topology and composition of DC distribution networks is first introduced.Then three typical grounding schemes according to the AC and DC side grounding points was proposed.The influence of different grounding modes on the single-phase grounding fault occurring at transformer value side in AC side was analyzed.Considering the case of the unblocked IGBT,the effect of poleto-ground fault in dc side was discussed.Finally,the advantage of transformer value side through neutral grounding in AC side was selected as DC distribution networks grounding mode was assessed.Useful references for selecting grounding modes and the protection configuration of DC distribution system was supplied by the analysis results.

关 键 词：直流配电网 模块化多电平换流器 接地方式 单极接地 故障分析 

分 类 号：TM72[电气工程—电力系统及自动化]