基于小波分析的暂态量选线式漏电保护方法的研究

Research of Method of Transient Component Line Selection Leakage Protection Based on Wavelet Analysis

针对中性点经消弧线圈接地的矿井高压电网选线困难的问题,文章提出了一种基于小波分析的暂态量选线式漏电保护方法。该方法利用零序电压稳态值越限和零序电压突变量越限判断电网是否漏电;利用小波奇异性检测原理精确定位故障时刻,以准确采样各线路暂态量;对采样暂态量进行小波包变换,计算由小波包系数构成的选线判据,并根据该选线判据进行漏电选线。仿真实验表明,该方法灵敏性高、选线准确,具有一定的可行性。

To solve the problem that mine high-voltage power network with neutral grounded by arc suppression coil is difficult to select line, the paper proposed a method of transient component line selection leakage protection based on wavelet analysis. The method uses steady value off-limit and break variable off-limit of zero-sequence voltage to judge if power network has leakage fault, uses detection principle of wavelet singularity to locate fault time accurately in order to sample transient component of each line precisely, and makes wavelet packet transform for sampled transient component to calculate line selection criterion formed by wavelet packet coefficient and make leakage line selection according with the criterion. The simulation experiment showed that the method has high sensitivity and accurate line selection, which has certain feasibility.