Phase Selection Method for Line Grounding Fault Using Sequence Current Phase Characteristics and Sequence Voltage Phase Characteristics

Abstract

The invention discloses a line ground fault phase selection method using a sequence current phase characteristic and a sequence voltage phase characteristic. The method is characterized by forming a criterion by using a phase relation between zero-sequence voltage and phase-A negative-sequence voltage to accurately determine whether a power transmission line fault is a grounding short circuit fault; and forming a criterion by using a phase relation between zero-sequence current and phase-A positive-sequence current sudden change to distinguish between a single-phase grounding short circuit fault and a two-phase grounding short circuit fault. If a power transmission line is subjected to a high resistance grounding short circuit fault when a weak power side and a system operation mode are changed a lot, the method has high phase selection sensitivity, may accurately determine a specific grounding fault phase, and may provide correct and reliable fault phase information for distance protection and an automatic reclosing correct action.

Description

technical field [0001] The invention relates to the technical field of electric power system relay protection, in particular to a phase selection method for line grounding faults using sequence current phase characteristics and sequence voltage phase characteristics. Background technique [0002] Phase selection methods for transmission line faults mainly include phase selection of phase current mutation, phase selection of phase voltage mutation and comprehensive phase selection of voltage and current mutation. On the weak power supply side, the phase selection sensitivity of phase current mutation is not high enough; on the strong power supply side, the phase selection sensitivity of phase voltage mutation is insufficient; although the comprehensive phase selection method of voltage and current mutation has relatively high The sensitivity of phase selection is good, but the sensitivity of three-phase short-circuit fault phase selection and high-resistance grounding short-c...

AI Technical Summary

Problems solved by technology

On the weak power supply side, the phase selection sensitivity of phase current mutation is not high enough; on the strong power supply side, the phase selection sensitivity of phase voltage mutation is insufficient; although the comprehensive phase selection method of voltage and current mutation has relatively high Good phase selection sensitivity, but insufficient sensitivity in phase selection for three-phase short-circuit faults and high-resistance grounding short-circuit faults

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