采用电流余弦相似度的含DG配网故障识别策略  

Fault Identification Strategy for Distribution Network with DGs Using Current Cosine Similarity

作　　者：李振兴[1] 徐浩[1] 傅裕挺 李振华[3] 翁汉琍[3] LI Zhenxing;XU Hao;FU Yuting;LI Zhenhua;WENG Hanli(College of Electrical Engineering&New Energy,China Three Gorges University,Yichang 443002,China;State Grid Xinzhou Electric Power Company,Xinzhou 034000,China;Hubei Provincial Key Laboratory for Operation and Control of Cascaded Hydropower Station(China Three Gorges University),Yichang 443002,China)

机构地区：[1]三峡大学电气与新能源学院,宜昌443002 [2]国网忻州供电公司,忻州034000 [3]梯级水电站运行与控制湖北省重点实验室(三峡大学),宜昌443002

出　　处：《电力系统及其自动化学报》2022年第4期1-10,共10页Proceedings of the CSU-EPSA

基　　金：国家自然科学基金资助项目(52077120)。

摘　　要：分布式电源接入致使配网故障情况更为复杂,负荷分支电流难以获取,导致电流差动保护难以应用。基于此,本文提出一种基于电流余弦相似度比较的配网故障识别新方法。基于余弦相似度理论,利用配网多分支测量信息,构建进线电源电流与各输出电流的余弦相似度比较判据,实现故障区域判别;利用故障区域干线测量信息,逆向逐级比较余弦相似度判断故障区段。针对上述两步骤,引入Petri网理论,提出基于正向、反向Petri网搜索概念与实现方法。在PSCAD中搭建含多分布式电源配网系统进行仿真,结果表明,比较余弦相似度解决了方向误判问题,基于2次定位方案能快速可靠识别故障区域。The access of distributed generations(DGs)makes the distribution network under fault more complicated,and the load branch current is difficult to obtain,which makes the current differential protection difficult to apply.On this basis,a novel fault identification method for distribution network based on the comparison of current cosine similarity is proposed in this paper.Based on the cosine similarity theory and using the multi-branch measurement information of the distribution network,the criterion for the comparison of cosine similarity between the incoming power supply current and each output current is constructed to realize the fault area discrimination.Using the trunk measurement information in the fault area,the cosine similarity is reversely compared step-by-step to determine the fault segment.For these two steps,the Petri network theory is introduced,and the concept and implementation method based on forward and reverse Petri network search are proposed.PSCAD is used to build the distribution network system with multiple distributed generations for simulation,and results show that the comparison of cosine similarity solves the directional misjudgment problem,and the fault area can be identified quickly and reliably based on the twice locating scheme.

关 键 词：波形比较 方向搜索 余弦相似度 PETRI网 故障定位 

分 类 号：TM773[电气工程—电力系统及自动化]