Double-circuit parallel transmission line single phase grounding fault point transition resistance value measuring method

Abstract

The invention discloses a double-circuit parallel transmission line single phase grounding fault point transition resistance value measuring method, which comprises the following steps of calculating zero-sequence current of an II circuit transmission line of a double-circuit parallel transmission line, and accurately calculating a single phase grounding fault point transition resistance value according to the linear relationship between voltage drop and fault distance from a protection installation part of a I circuit transmission line of the double-circuit parallel transmission line to a single phase grounding fault point. The method considers the influences of zero sequence mutual inductance between lines and single phase grounding fault point voltage, overcomes the influences of transition resistance, load current and zero sequence mutual inductance between the lines on single phase grounding fault point transition resistance value measuring accuracy, and has higher measurement accuracy.

Description

Technical field [0001] The invention relates to the technical field of power system relay protection, in particular to a method for measuring the transient resistance value of a single-phase ground fault point of a double-circuit line on the same pole. Background technique [0002] Parallel double-circuit lines on the same pole have a small footprint, low cost, stable and reliable operation of connecting to the grid, and have become a common transmission line connection method for power systems. The operating environment of parallel double-circuit lines on the same pole is complicated, and there are many types of fault factors. The factors that cause ground faults in the double-circuit lines on the same pole are insulator flashover, lightning strikes, floating objects, burning mountains, villagers’ burning, line-to-branch discharge, and lines Discharge of bamboos, bird hanging grass causes insufficient safety distance between lines, bird hanging grass causes insufficient safety d...

AI Technical Summary

Problems solved by technology

The operating environment of double-circuit lines paralleled on the same pole is complex, and there are many types of fault factors. The factors that cause ground faults of double-circuit lines paralleled on the same pole include insulator flashover, lightning strikes, floating objects, burning mountains, villagers burning wasteland, line discharge to tree branches, line Discharge of moso bamboo, insufficient safety distance between lines caused by birds hanging grass, insufficient safety distance between lines and ground wire caused by birds hanging grass, etc.

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