基于小波变换的矿井电网故障行波定位

Traveling wave fault location of underground power grid based on the wavelet transform

针对矿井下由于条件恶劣经常造成的电缆接地短路故障,分析了快速找到故障点对矿井下供电安全的重要性,将已在大电力系统中广泛应用的行波测距引入到井下电路故障的定位中,根据实际情况改进了单端测距算法,并利用小波变换来提取故障行波的特征信息,通过小波系数的模极大值计算确定信号的突变点。仿真实例表明此方法能实现对矿井下电网故障较为准确的定位。

In view of the cable grounding short circuit fault caused by mal-condition in coal mine,this paper analyzes the timely discovery of the fault point is of great importance to coal mine power supply security,then traveling-wave based fault location which has been widely used in large power system is introduced into the underground circuit fault positioning,the single-ended fault location algorithm is improved according to the actual situation and the feature information of the fault travelling wave is extracted using wavelet transform,and through the calculation of modulus maxima of wavelet coefficient to confirm the breakpoint of the signal. Simulation examples show that this method can realize relatively accurate position of the underground power grid fault.