基于改进双端法的输电线路行波故障定位

Traveling waves fault location of transmission lines based on improved double-end method

行波波速的不确定往往给行波故障定位带来较大误差。为了克服行波波速对输电线路故障行波定位的影响,提出了一种利用同一条线路的三个测量点进行故障定位的方法。在双端行波故障定位原理的基础上,构造了一个三测点的定位系统,推导出不受行波波速影响的故障定位新算法。该方法利用小波变换确定故障初始行波到达三个测量点的时间即可实现故障定位,与以往方法相比避免了因行波反射衰减无法测量而导致定位失败。PSCAD仿真结果表明,该方法定位精度高,且简单易行。

The uncertainty of traveling wave speed always causes big deviations to the fault location. In order to con- quer the influence of traveling wave speed on transmission line fault location, a new method of fault location by using three measurement points on the same line was presented in this paper. Based on the principle of double - end trave- ling wave fault location, a locating system with three measurement points was constructed, and a new locating algo- rithm without influence of wave speed was derived. It needs the time of the fault initial traveling wave arriving at three measurement points to realize fault location, the time can be determined by wavelet transform, compared with the pre- vious methods. Compared with the traditional method, it can avoid the locating failure that caused by the attenuation of the reflecting wave. The simulation results of PSCAD show that the proposed method has high accuracy in location, and it is easy to implement.