Single-ended transmission line fault distance measuring method based on reclosing action analysis

Abstract

The invention discloses a single-ended transmission line fault distance measuring method based on reclosing action analysis. According to the principle of circuit superposition, the additional state network in a fault state and the additional state network in an automatic reclosing state after fault are analyzed, and an equation set of the measured voltage and current of the current side with respect to the fault distance, the transition resistance and the opposite-side system impedance in a positive sequence fault component state is established. Finally, the equation set of the fault state and the reclosing state is solved by using a trust region reflection algorithm to obtain the accurate fault distance. The method of the invention completely overcomes the problem that the traditional single-ended method cannot simultaneously eliminate the influences of the fault distance, the transition resistance and the opposite-side system impedance on the distance measurement accuracy due to limited information available.

Description

technical field [0001] The invention relates to the technical field of electric power system relay protection, in particular to a single-end transmission line fault distance measurement method based on reclosing action analysis. Background technique [0002] Fast and accurate fault location technology is of great significance for repairing faults, quickly restoring power supply, and improving power system reliability and continuity. According to the principle of distance measurement, fault distance measurement is mainly divided into traveling wave method and fault analysis method. [0003] The traveling wave method calculates the fault distance according to the time difference of the traveling wave arriving at the measuring point after the fault, which has high precision in principle. However, it is difficult to detect wave head and wave speed, and the equipment cost is too high. The fault analysis method uses information such as the steady-state voltage and current before...

AI Technical Summary

Problems solved by technology

[0004] The purpose of the present invention is to provide a method to solve the problem of limited measurement information available in the single-ended method in order to overcome the above-mentioned defects in the prior art, and analyze multiple time levels (fault state and reclosing state) to extract more effective Information, using distributed line parameters, establishes the equations of single-ended electrical quantity and fault distance, transition resistance and opposite-side system impedance in the fault state and single-phase reclosing state, and solves the equations through the trust region reflection algorithm to obtain accurate Fault distance, easy to apply, a single-ended transmission line fault location method based on reclosing action analysis that can be applied to the existing transmission system only through the fault recorder and line parameters in the substation

Images