Power distribution network single-phase earth fault detection algorithm based on phase current similarity

Abstract

The invention provides a power distribution network single-phase earth fault detection algorithm based on phase current similarity. The detection algorithm includes: firstly, according to a three-phase current acquisition terminal installed in a power distribution network, acquiring current sampling data within td time before and after a single-phase earth fault moment, and synthesizing a current break variable sequence; according to the characteristic that the waveform similarity between the current break variables, close to the bus side, of a fault point is low and the waveform similarity between the current break variables, close to the load side, of the fault point is high, calculating the HD distance between the current break variables of all the acquisition terminals; judging a fault feeder line according to the current break variable similarity of the current acquisition terminal, closest to the bus, of each feeder line; according to the current break variable similarity of the current acquisition terminals of the fault feeder line, judging that the acquisition terminal is located at a fault point near a bus side or a load side, and determining a fault position; and finally, realizing fault phase selection through similarity of three-phase current break variables at the fault point. According to the method, the influence caused by a branch line and a cable overhead hybrid line can be avoided, and bootstrap performance is achieved.

Description

technical field [0001] The invention relates to a single-phase ground fault detection algorithm of a distribution network based on phase current similarity. Background technique [0002] Existing single-phase grounding fault section location methods in non-effectively grounded distribution networks can be divided into two categories according to their use of different information: one is the fault section location method based on external injection signals; the other is using the electrical quantity at the time of the fault Fault section location based on changing characteristics, which can be divided into fault section location method based on fault steady state component, fault section location method based on fault transient component and comprehensive information location method. According to practical application experience, the network structure of the medium voltage distribution network is complex, with many line branches. The phase current and current characteristic...

AI Technical Summary

Problems solved by technology

Seriously affect the practicability of the traditional section location method based on the similarity of uploaded phase current and current characteristics

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