基于VMD和SDEO的低采样率行波故障定位算法  

A new algorithm of travelling wave fault location based on VMD and SDEO with low sampling rate

作　　者：杨安琪[1] 龚庆武[1] Yang Anqi;Gong Qingwu(School of Electrical Engineering,Wuhan University,Wuhan 430072,China)

机构地区：[1]武汉大学电气工程学院,武汉430072

出　　处：《电测与仪表》2018年第6期1-7,15,共8页Electrical Measurement & Instrumentation

基　　金：国家科技支撑计划资助项目(2013BAA02B01)

摘　　要：针对传统行波测距方法易受波速不确定性影响和需要在较高采样率下才能保证测距精度的问题,提出了一种基于变分模态分解(VMD)和对称差分能量算子(SDEO)的低采样率行波故障定位算法,该算法充分利用了初始行波波头的到达时刻和线路长度来消除波速对故障测距的影响,提高了定位精度。并将变分模态分解和对称差分能量算子相结合,利用分解的模态稳定性强的优点和能量算子优异的跟踪信号奇异性的特点,使该算法在较低采样率下也能精确地检测出波头的瞬时能量突变时刻,从而准确定位故障的发生点。EMTP仿真结果验证了所提方法的测量精度较小波故障定位方法有所提升,而且能够节约设备成本,适合于工程实际中的应用。In view of the facts that traditional traveling wave fault location method is susceptible to the uncertainty of wave velocity and the accuracy of the location is dependent on the high sampling rate,an improved fault location algorithm based on variational modal decomposition(VMD)and symmetric difference energy operator(SDEO)is proposed in this paper.This algorithm makes full use of arrival time of the first transient traveling wave and the length of the transmission line,which eliminates the influence of wave velocity on the fault location and thus can improve the precision of location.The proposed algorithm combines the strong stability of the variational modal decomposition and the high tracking accuracy of the singularity of the signal with symmetrical differencing energy operator,so that the algorithm can determine the time when the mutation of instantaneous energy of the wave head occurs at low sampling rate,so as to exactly locate the fault.Simulation results by EMTP indicate that this method has a better performance for measurement accuracy than that of fault location based on wavelets.It can also economize the equipment expenses and it is suitable for engineering applications.

关 键 词：行波测距 变分模态分解 对称差分能量算子 低采样率 小波分析 

分 类 号：TM761[电气工程—电力系统及自动化]