基于小波包分解的直流电缆泄漏电流分析研究

Leakage current analysis of DC cable based on wavelet packet decomposition

直流电缆泄漏电流指的是由线芯流经主绝缘至金属护层的电流,能反映介质整体受潮与整体劣化的情况。不同故障缺陷的直流电缆中的泄漏电流波形存在差异。基于交联聚乙烯电缆构建了3种常见的故障模型,对采集到的泄漏电流信号进行小波包变换分析。将同种缺陷不同电压下的信号以及不同缺陷的泄漏电流信号波形进行对比分析,结果表明小波包分解方法能有效分析直流电缆的泄漏电流,根据不同缺陷的泄漏电流特征推断故障模式。

The leakage current in a DC cable refers to the current flowing through the main insulation from the core to the metal sheath, reflecting the overall moisture and overall deterioration of the medium. There are differences in the different leakage current waveforms in DC cables correspond to different fault defects. In this paper, three common fault models are constructed based on XLPE cables, and the collected leakage current signals are analyzed by wavelet packet transform. The results show that the wavelet packet decomposition method can effectively analyze the leakage current of DC cables and deduce the fault modes according to the leakage current characteristics of different defects.