小波变换在电力线路故障选线中的应用

摘要

The power line fault caused by uncertainty brings great challenges to the safe operation of power grid.In this article, wavelet transform was used as a signal processing method.The research and application of wavelet transform in fault line selection of power line were analyzed.This method used the well timefrequency analysis ability of wavelet.In China the neutral point of the medium and low voltage distribution networks commonly use arc suppression coil grounding.For this situation, the distribution and characteristics of steady component and transient highfrequency component existing in the small current ground system singlephase grounding fault.The fault line selection was implemented by wavelet packet transform after extracting the zero sequence current.The correctness and effectiveness of the method were verified by a numerical example.%由不确定性因素引发的电力线路故障给电网安全运行带来了巨大挑战.文中将小波变换作为一种信号处理方法,分析小波变换在电力线路故障选线中的研究与应用现状.该方法利用小波良好的时频分析能力,针对我国中低压电网的中性点普遍采用经消弧线圈接地的情况,讨论小电流接地系统中发生单相接地故障时稳态分量和高频暂态分量的分布及各自的特点,提取各线路零序电流后利用小波包变换实现故障选线.通过算例仿真验证了所用方法的正确性和有效性.