一种基于频率选择的输电线路故障行波测距方法  

A method of fault location for transmission line based on frequency selection

作　　者：周志通 陈永琦 黄璜 蒋亮 ZHOU Zhitong;CHEN Yongqi;HUANG Huang;JIANG Liang(Datang Hydropower Science&Technology Research Institute Co.,Ltd,Chengdu 610036;School of Electrical Engineering and Information,Southwest Petroleum University,Chengdu 610500)

机构地区：[1]大唐水电科学技术研究院有限公司,成都610036 [2]西南石油大学电气信息学院,成都610500

出　　处：《电气技术》2024年第2期31-36,44,共7页Electrical Engineering

基　　金：南充市市校合作项目(SXQHJH044)。

摘　　要：为解决行波测距法中行波频率过高使测距所需波头幅值降低,进而导致测距失败的问题,本文通过分析频率对行波波头幅值的影响规律,提出一种基于频率选择的故障行波测距方法。首先对故障行波信号做经验模态分解(EMD),获得不同频率段的固有模态函数(IMF)分量,同时对IMF分量做Hilbert变换和一阶微分处理,提取并绘制不同高频IMF分量对应的幅值-时间曲线,通过选择波头幅值较大且频率相对低的高频IMF分量对行波波头进行检测,在保证波头检测精度的前提下,减少因行波频率过高导致信号衰减加剧的影响,最后结合三端行波测距算法完成故障测距。仿真结果表明,本文所提方法的相对误差在±0.3%以内,绝对误差在±0.9km以内,与传统的瞬时频率定位方法相比,具有更高测距精度。In order to solve the problem that the high frequency of traveling wave makes the wave head amplitude lower,which leads to the failure of fault location,this paper proposes a frequency selection based traveling wave fault location method by analyzing the effect of frequency on the traveling wave head amplitude.Firstly,the empirical mode decomposition(EMD)of the fault traveling wave signal is done to obtain the intrinsic mode function(IMF)components of different frequency bands.The Hilbert transform and first-order differentiation are done on the IMF components,and the amplitude-time curves corresponding to the different high-frequency IMF components are extracted and plotted,so that the traveling wave head can be detected by selecting the high-frequency IMF components with larger amplitude of the wave head and lower frequency.Thus it reduces the impact of signal attenuation caused by excessive travelling wave frequency,and ensures the accuracy of the wave head detection.Finally,the fault location is completed the three-terminal traveling wave location algorithm.Simulation results show that the relative error of the method proposed in this paper is basically within 0.3%,and the absolute error is within 0.9km,which has higher location accuracy compared with the traditional instantaneous frequency location method.

关 键 词：故障测距 频率选择 瞬时振幅 输电线路 

分 类 号：TM75[电气工程—电力系统及自动化]