行波时频复合分析的配电网故障定位研究  

Research of Fault Location in Distribution Networks Based on Integration of Travelling Wave Time and Frequency Analysis

作　　者：梁睿[1] 靳征[2] 王崇林[1] 刘建华[1] 

机构地区：[1]中国矿业大学信息与电气工程学院,江苏省徐州市221116 [2]山东电力集团公司东营供电公司,山东省东营市257000

出　　处：《中国电机工程学报》2013年第28期130-136,20,共7页Proceedings of the CSEE

基　　金：中国博士后科学基金(2013M531427);中央高校基本科研业务费专项资金(2011QNA19)~~

摘　　要：单端行波检测要实现单相接地故障精确测距,必须确定故障初始波头与其他反射波头的时间差,而准确识别故障反射波头的问题一直没有很好解决。为此,提出了一种精确识别故障点反射波头的方法。首先,在连续小波变换(continuous wavelet tranformation,CWT)自建母小波的单相接地故障信号频域分析的基础上,较为准确地得到故障点的特征频率,从而初步确定故障的距离;然后根据频域分析方法得到的故障初步位置结合Daubechies(Db)小波对信号进行时域分析,准确判别故障线路对侧母线反射波头到达时刻,进而利用初始波头与对侧母线反射波头时间差实现故障精确测距。大量仿真实验表明,该方法能精确地辨别反映故障距离的对端母线反射波头,提高了行波频域分析的精度与时域分析的可行性,通过对故障暂态信号的时频域综合分析,较好地实现了单端辐射状配电网单端故障测距。Calculation of the time difference between initial and reflected wave fronts originated from fault point is a key issue based on single terminal traveling wave method for single-phase ground fault location. But accurate identification of the reflected wave fronts from fault point have been not solved well yet. The paper proposed a new method for accurate identification of the reflected wave fronts. Firstly, transient signal originated from fault point is analyzed in frequency domain by fault waveform-inferred mother wavelets of continuous wavelet transformation （CWT）, the precise characteristic frequency is obtained and fault location preliminarily determined. Secondly, the fault location determined from the previous step is used as a clue for Daubechies （Db） wavelet time domain analysis, and the arrival time of the reflected wave fronts from the far terminal bus is determined. Finally, more precise fault location is achieved based on the time difference between initial wave front from fault point and reflected one from far terminal bus. Many simulations show that reflected traveling waves associated with fault location have been accurately identified, precision in frequency domain analysis and feasibility in time domain analysis are both improved. The method integrates time and frequency domain analysis and gets a more accurate single terminal fault location procedure for radial power distribution network.

关 键 词：故障测距 行波 时频域分析 单相接地故障 波头识别 

分 类 号：TM77[电气工程—电力系统及自动化]