摘要
快速、准确地定位配电线路故障点对提高供电可靠性、实现智能电网具有重要的意义。提出一种新的接地故障行波信号时频分析方法,对故障电流的线模分量和零模分量进行经验模态分解(Empirical mode decomposition,EMD),得到多阶平稳的固有模态函数(Intrinsic mode function,IMF),第一阶IMF含有较高的频率分量,能反映信号的突变,对第一阶IMF进行Hilbert-Huang变换,得到信号的瞬时频率。由时频图中的瞬时频率检测出行波波头的到达时刻,通过线模和零模波头之间的时间差计算出故障距离。仿真分析表明,该算法能准确检测故障距离,不受接地过渡电阻、短路时刻的影响。
It is of great significance for power supply reliability and smart grid to locate the point of failure on distribution lines quickly and accurately.A new ground fault traveling-wave signal time-frequency analysis method is put forward.It decomposes the line mode component and zero mode component of fault current based on empirical mode decomposition(EMD)to get multi-stage stable intrinsic mode function(IMF).The first IMF contains more frequency components which can reflect the mutation of signal.Transform the first IMF with Hilbert-Huang transformation to get the instantaneous frequency of signal.And then check the moment when the head wave of traveling wave arrived using the instantaneous frequency in the fig of time-frequency.Account the fault distance based on the time difference between the moment of head wave arrived of line mode component and zero mode component.Simulation analysis proves that this method is able to accurately account the distance of fault in the influence of the random factors such as fault transition resistance and the moment of fault.
作者
王艳松
徐海亮
衣京波
梁硕
WANG Yansong;XU Hailiang;YI Jingbo;LIANG Shuo(College of New Energy,China University of Petroleum(East China),Qingdao 266580;Shengli Power Plant,Shengli Petroleum Administration,Dongying 257087)
出处
《电气工程学报》
2020年第4期18-26,共9页
Journal of Electrical Engineering
基金
国家重点研发计划资助项目(2018YFB0904800)。
