Undercurrent grounding system fault positioning method suitable for monitoring branch line

Abstract

The invention discloses an undercurrent grounding system fault positioning method suitable for monitoring a branch line, belongs to the field of fault detection of a power distribution network, and brings forward a positioning method for determining a search path and finding out a fault section step by step through integrated utilization of a similarity and polarity relation between transient zero-mold currents of each monitoring point of the upstream and downstream of each section, for solving the problem of positioning a single-phase grounding fault in an undercurrent grounding mode distribution system for monitoring a branch line through a terminal. According to a fault line selection result, first of all, a first section of a fault line outlet is selected as an undetermined section, a correlation coefficient between the transient zero-mold currents of each monitoring point of the upstream and downstream of the undetermined section is calculated, and whether the undetermined section is a fault section is determined according to the correlation coefficient and a polarity feature; and if the undetermined section is a sound section, a next undetermined section is determined according to the amplitude size of the transient currents until the fault section is found. According to the invention, in actual application, the power distribution network has too many branches. The method provided by the invention solves the positioning problem in the distribution system for monitoring the branch line through the terminal and has a wide actual application value.

Description

technical field [0001] The invention relates to a fault location method for a small current grounding system, which is suitable for a power distribution system in a small current grounding mode and belongs to the field of fault detection of distribution networks. Background technique [0002] When a single-phase (small current) ground fault occurs in a small current grounding distribution network, on the basis of fault line selection, the distance to the fault point or the fault section can be determined, which can further shorten the fault finding and repair time, and will become a small current ground fault The hotspots and key points of detection technology research and application. The traditional method of fault detection (line selection, positioning and distance measurement) using steady-state electrical quantities has problems such as insignificant, unstable or even uncertain fault quantities, and cannot guarantee the reliability and sensitivity of detection. After r...

AI Technical Summary

Problems solved by technology

[0005] The purpose of the present invention is to solve the problem of fault location when single-phase grounding occurs in the small current grounding system of monitoring branch lines, and to provide a fault location method based on zero-mode current transient components

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