验证小波变换行波故障测距法的现场试验

一般行波故障测距法较少考虑行波传播的色散情况，没有很好解决如何精确确定行波的到达时间和行波传播速度等问题，使测距精度受到影响。为解决现有行波法的不足，提出一种新的利用小波变换技术进行双端行波测距的方法，并用大型现场短路试验对该方法的可行性及实际测距精度进行了验证。文章介绍了现场短路试验的有关情况以及部分试验数据的整理和分析结果，对小波变换测距法与传统行波测距法进行了比较。试验结果表明，小波变换测距法比传统行波测距法准确，且故障时不受电压相角等因素的影响，定位精度在300m以内，因此，将小波变换应用于行波故障测距是可行的。

FIELD SHORT-CIRCUIT TEST TO VALIDATE TRAVELLING WAVE FAULT LOCATION USING WAVELET TRANSFORM

Existing methods for travelling wave fault location seldom consider the attenuation and distortion of travelling wave propagating in transmission line and do not solve the problems to define the arrival time of travelling wave and the propagation velocity properly, which leads to poor location accuracy. For this reason a new double terminal travelling wave method using wavelet transform (WT) is presented. A field short-circuit test has been performed to validate the applicability and accuracy of the new method. This paper describes the field test and the analysis results of the test data, meanwhile a comparison between WT method and traditional method is given. The field test results show that the accuracy of WT method is higher than that of traditional method and not affected by many factors, such as fault occurring voltage angle. The new method is capable of locating faults on transmission lines with accuracy up to ± 300 meters. WT is suitable for travelling wave fault location.