Arc detecting method for grounding fault of overhead bare conductor through trees

Abstract

The invention discloses an arc detecting method for grounding fault of an overhead bare conductor through trees. The arc detecting method comprises the steps that discrete transformation is conductedon real-time collected three-phase voltage signals and three-phase current signals, and a voltage residual sequence and a current residual sequence are obtained; the voltage residual sequence is a changing value of the three-phase voltage signals before and after changing, the current residual sequence is a changing value of the three-phase current signals before and after changing; summation values in all sliding windows of the voltage residual sequence are calculated, and whether an arc exists in a distribution line or not is judged according to the summation values; the sliding windows aretime sequence windows with specified time lengths; if the arc exists, matrix multiplications of the voltage residual sequence and the current residual sequence in all the sliding windows are calculated; and whether the arc exists in a branch line behind a measured point or not is determined according to the matrix multiplications. According to the arc detecting method for grounding fault of the overhead bare conductor through the trees, the nonlinear higher harmonic content of travelling waves of the voltage and current can be extracted, calculation is easy, and the accuracy of arc detecting can further be improved.

Description

technical field [0001] The present application relates to the technical field of power systems, in particular to an arc detection method for ground faults of overhead bare conductors passing through trees. Background technique [0002] Overhead bare conductors in Yunnan distribution network account for more than 75% of the total length. At the same time, due to the mountainous area of ​​Yunnan reaching more than 80%, most of the overhead bare conductors are located in mountainous areas. Due to the inhomogeneity of the grounding medium such as trees, the equivalent transition resistance of the grounding is non-linear, and intermittent arcs often accompany it. Therefore, the timely implementation of arc detection after the ground fault occurs can be used as the basis for ground fault type identification and fault section location, which is of great significance to the fault handling of the plateau distribution network. [0003] A PMU (Power Management Unit, Power Management U...

AI Technical Summary

Problems solved by technology

[0006] This application provides an arc detection method for overhead bare conductors passing through trees to ground faults, in order to solve the problems of high computational complexity and low detection accuracy of the arc detection method

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