基于改进欧氏-动态时间弯曲距离的谐振接地配电网单相高阻接地故障选线方法  

A Line Selection Method for Single-phase High-impedance Grounding Fault in Resonant Grounding System of Distribution Network Based on Improved Euclidean-dynamic Time Warping Distance

作　　者：庄胜斌 缪希仁[1] 江灏[1] 郭谋发[1] ZHUANG Shengbin;MIAO Xiren;JIANG Hao;GUO Moufa(College of Electrical Engineering and Automation,Fuzhou University,Fuzhou 350116,Fujian Province,China)

机构地区：[1]福州大学电气工程与自动化学院

出　　处：《电网技术》2020年第1期273-281,共9页Power System Technology

基　　金：国家自然科学基金项目(51377023)~~

摘　　要：针对谐振接地系统发生单相高阻接地故障时单一特征量故障信息不明显,以及故障线路与非故障线路暂态零序电流存在明显差异的特点,提出一种基于改进欧式-动态弯曲距离的单相高阻接地故障选线新方法。将动态弯曲距离与欧式距离相结合,求取各线路故障2个周期后暂态零序电流波形的相似度矩阵,构建各线路波形的综合相似系数,并结合模糊C均值聚类算法,实现单相高阻接地故障选线。对于工程应用中线路参数差异造成的非故障线路暂态零序电流波形相似性低的问题,对原始波形进行预处理,以提高选线方法的可靠性。通过大量仿真,验证选线方法对单相高阻接地故障和各类接地故障的有效性。在噪声干扰、采样不同步、零序电流互感器极性反接、两点高阻接地等极端情况下,选线方法具有较强的鲁棒性和容错性。For the single-phase high-impedance ground fault(HIF)in resonant grounding system,single characteristic quantity fault information is not obvious,and there is a significant difference in transient zero-sequence currents between fault line and non-fault line.A new method of single-phase HIF line selection based on improved Euclidean-dynamic time warping(E-DTW)distance is proposed.Firstly,the similarity matrix of the transient zero-sequence current waveforms after two cycles of fault is obtained by combining dynamic time warping(DTW)distance with Euclidean distance,and a comprehensive similarity coefficient of each line waveform is constructed.Then fuzzy C-means clustering(FCM)algorithm is used to realize single-phase HIF line selection.In addition,because similarity of the non-faulty line transient zero-sequence current waveforms caused by the difference of line parameters in engineering application is low,the original waveform is preprocessed to improve reliability of the line selection method.Simulation results show that the proposed method is effective for both single-phase HIFs and various ground faults.Even in the extreme cases,such as noise interference,asynchronous sampling,polarity reverse connection of zero-sequence current transformer,and two-point high-impedance grounding,the line selection method is still strongly robust and fault-tolerant.

关 键 词：谐振接地系统 单相高阻接地故障 波形预处理 改进欧氏-动态弯曲距离 模糊C均值聚类 

分 类 号：TM76[电气工程—电力系统及自动化]