基于小波变换的双端输电线路行波故障定位

为了消除行波波速不确定性和线路弧垂对双端输电线路行波故障定位造成的误差影响,提出了一种在输电线路中间某一位置增加一个检测点的三测点定位方法;该方法首先对电流行波信号进行相模变换,得到相互独立的线模分量,其次对得到的线模分量进行小波分析,检测出行波波头到各测量点时间,最后代入相应的公式计算出故障距离; MATLAB仿真实验结果表明:该方法不受过渡电阻、行波波速、故障类型等因素的影响,测距误差较小,原理简单,具有较高的准确性和良好的适用性。

Traveling Wave Fault Location of Double-ended Transmission Lines Based on Wavelet Transform

In order to eliminate traveling wave wave velocity uncertainty and the error from the influence of line sag on the traveling wave fault location of double-ended transmission lines, a three-point positioning method is proposed to add a detection point at a certain position in the middle of transmission line.Firstly, the current traveling wave signal is phase-mode-converted to obtain mutually independent linear mode components.Secondly, the obtained linear mode component is subjected to wavelet analysis, and the time from traveling wave head to each measuring point is detected.Finally, the corresponding formula is substituted to calculate the fault distance.The simulation results of MATLAB show that the method is not affected by the factors such as transition resistance, traveling wave velocity and fault types and so on.The method, with small error range for detected distance and with simple principle, has high accuracy and good applicability.