Skewness can be used to identify the asymmetry introduced into a current stream by a High Impedance Fault (HIF). This letter introduces relative skewness as a superior computational approach for detecting HIF induced asymmetry changes in the feeder current. Relative skewness is defined as a measure of asymmetry in the stream with respect to the stream itself. The key highlight is the analysis of four different methods for detecting HIF induced asymmetry changes for HIF currents as low as 0.5 Amps. The work confirms Pearson's moment coefficient of skewness as the most efficient method in producing the highest asymmetry separability in the post fault average skewness. The letter concludes by proposing a technique in discriminating HIF induced skewness changes from those by other likely disturbances.

中文翻译：

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高阻抗故障中不对称检测偏度方法的性能分析

偏度可用于识别由高阻抗故障 (HIF) 引入电流的不对称性。这封信介绍了相对偏度作为检测馈线电流中 HIF 引起的不对称变化的高级计算方法。相对偏度被定义为流中相对于流本身的不对称性的度量。主要亮点是对检测低至 0.5 安培的 HIF 电流的 HIF 感应不对称变化的四种不同方法的分析。这项工作证实了 Pearson 偏斜矩系数是在故障后平均偏斜中产生最高不对称可分性的最有效方法。这封信最后提出了一种技术，可以将 HIF 引起的偏度变化与其他可能的干扰引起的偏度变化区分开来。