Method of single end distance measurement of power transmission line malfunction based on traveling wave inherent frequency extraction

Abstract

The invention discloses a method of single end distance measurement of power transmission line malfunction based on traveling wave inherent frequency extraction. The method comprises the following steps of: after extracting to analyze a principal component of the inherent frequency of a current traveling wave signal of the power transmission line malfunction, selecting a corresponding modulus and a failure type according to the principal component frequency and the malfunction type; obtaining a circuit characteristic impedance matrix, a reflection coefficient matrix, a reflection angle matrix and a modulus wave velocity under the principle component frequency; finally calculating out distance of the malfunction according to the traveling wave inherent frequency, the modulus wave velocity, and the reflection angle, and providing a distance measurement result of the power transmission line malfunction. The method can effectively extract the principal component frequency of the current traveling wave of the power transmission line malfunction, and has the accurate and reliable distance measurement result and convenient implementation without special requirements on equipment.

Description

technical field [0001] The invention relates to a single-end ranging method for transmission line faults in a power system. Background technique [0002] The traveling wave fault location method is the current mainstream fault location method. Traveling wave fault location is less affected by factors such as transition resistance and can achieve higher accuracy. However, the single-ended traveling wave distance measurement method only needs the signal of the line measurement terminal and does not need synchronous equipment, so it has good economy. However, since traveling wave head identification is mostly carried out in the time domain, the diversity of faults and the influence of waveform distortion will inevitably lead to errors or even complete misjudgments in distance measurement. It is difficult to identify the bob head, what's more, the "mode mixing" phenomenon will further deteriorate the measurement accuracy under the condition of asymmetrical short circuit fault....

AI Technical Summary

Problems solved by technology

However, since traveling wave head identification is mostly carried out in the time domain, the diversity of faults and the influence of waveform distortion will inevitably lead to errors or even complete misjudgments in distance measurement. It is difficult to identify the wave head, what's more, the "mode mixing" phenomenon will further deteriorate the measurement accuracy under the condition of asymmetrical short circuit fault

In short, it is difficult to accurately identify and extract the arrival time of the fault traveling wave head and accurately estimate the shape of the fault traveling wave head in various conditions and noise environments, so the measurement accuracy is low and the measurement error is large.

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