基于小波变换的单相高阻接地故障检测方法

Research on single-phase high-impedance fault detection method based on wavelet transform

提出了一种基于小波变换的中性点不接地系统的单相高阻接地故障检测方法.发生故障时,经过小波变换,故障相电流和零序电流高频系数模极大值在相同时间和位置的极性相同,而非故障相的高频系数模极大值与零序的高频系数模极大值极性相反;故障相的高频系数比非故障相的高频系数大很多,可作为接地检测的依据.通过ATP仿真验证可知,该方法能准确地检测出单相高阻接地故障.

A single-phase high-impedance fault （HIF） detection method for neutral point ungrounded system based on wavelet transform is proposed. Research shows., when the HIF occurs, via wavelet transform, the high-frequency coefficients modulus maxima of the fault phase current and the zero sequence current are of the same polarity at the same time and location, and the high-frequency coefficients modulus maxima of non-fault phases have the opposite polarity compared with that of the zero sequence ~ the high-frequency coefficients of the fault phase are much larger than that of the non-fault phase, which can be used to detect HIF. ATP simulation validation demonstrates that the method can be used to detect HIF with high reliability.