基于改进希尔伯特-黄变换的电缆接地故障定位研究

Study on Cable Grounding Faults Location Based on Modified Hilbert-Huang Transform

为了精确定位电缆接地故障区域,利用基于集合经验模态分解的希尔伯特黄变换与行波测距相结合的方法来实现电缆接地故障定位。针对经验模态分解易出现模态混叠导致最终对信号进行时频分析时无法计算行波往返于测量点和异常点之间时间的问题,提出利用集合经验模态分解来替换经验模态分解,然后使用改进HHT对故障行波信号进行分析,从而对电缆故障发生点进行定位。案例分析结果表明所提方法的故障定位精度误差为0.17%,能精确定位电缆接地故障区域。

Aiming at accurate location of fault areas of cable grounding,this paper proposes a method combination of EEMD-based modified Hilbert-Huang transform and traveling wave location.In consideration of the incompetence of EMD in determining time cost of wave traveling round between measured point and abnormal point caused by highly probable mode mixing,the ensemble empirical mode decomposition(EEMD)is proposed to replace the EMD.And then the modified HHT is used to analyze fault traveling wave signal so as to determine cable′s fault location.The results of practical case analysis show that the proposed method achieves a location error of 0.17%and can accurately locate cable grounding fault area.