A fault line selection method for distribution network based on integrated power frequency and transient reactive power directions

Abstract

The invention relates to the technical field of power distribution network fault detection, in particular to a power distribution network fault line selection method combining power frequency and transient state reactive power directions. After a single-phase earth fault occurs, an outgoing line with a large transient state zero sequence current amplitude value is firstly selected as a fault alternative outgoing line; then the transient state reactive power and power frequency reactive power of the fault alternative outgoing line are calculated, a sign function of the power frequency reactive power is utilized for correcting the transient state reactive power, and the corrected transient state reactive power is utilized for finding out a fault outgoing line. The problem of single-phase earth fault line selection with uncertain TV and TA polarity in a small current neutral grounding mode power distribution system is solved. During practical application, the TV and TA polarity of a power distribution network is unknown, the problem of single-phase earth fault line selection with uncertain TV and TA polarity in a small current grounding system is solved, and wide practical application value is achieved.

Description

technical field [0001] The invention relates to the technical field of distribution network fault detection, in particular to a fault line selection method for distribution network in the direction of integrated power frequency and transient reactive power. Background technique [0002] The 6 ~ 35kV medium voltage distribution network in my country mostly adopts the resonant grounding method, and the arc suppression coil is generally in an overcompensated state. Although this improves the fault self-healing level and power supply reliability, the overcompensated inductance current makes the power frequency zero-sequence current polarity of the fault line the same as that of the healthy line, and the amplitude is even smaller than that of the healthy line, which makes the traditional use of steady-state electrical quantities The line selection method has problems such as insignificant faults, instability or even uncertainty, and cannot guarantee the reliability and sensitivit...

AI Technical Summary

Problems solved by technology

However, the algorithm is not easy to understand in principle, and the line selection process is slightly complicated

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