Research on Assisted Strategy of Fault Line Selecting Method for Single-phase Ground Fault in Distribution Netword Base on Automation System

Abstract

In order to effectively improve the working efficiency of dispatchers using the ‘pull test method’ for single-phase ground fault line selection, this paper presents avariety of steady-state electrical quantities such as voltage, current, and reactive power obtained based on the distribution automation system, and combined with the line topology to generate fault line selection auxiliary strategies for different grounding systems that based on the superposition of multi-dimensional elements. Explained the technical principle of identifying the nature and phase of ground faults. Analyzed and introduced the organic fusion technology of fault features in multiple dimensions such as zero-sequence current amplitude, zero-sequence current mutation, reactive power mutation, etc. for different grounding methods and arc suppression coil compensation modes. Than formed "pull test"sequence of all lines. The proposed method does not require the addition of special hardware equipment or the transformation of the neutral point of the substation, not only saves investment, but also effectively reduces the number of line test pulls, and realizes rapid identification and accurate line selection of single-phase ground faults. The feasibility and applicability of this method were demonstrated in combination with specific projects.