A method for diagnosing short-circuit faults of power system transmission lines

Abstract

The invention discloses a novel power system electric transmission line fault diagnosis method. The method includes the steps that first, fault recording wave signals of an electric transmission line are extracted, and a three-phase current value and a discrete value of an earth current of the electric transmission line are obtained through discrete wavelet transform; then, according to a wavelet function db10, the wavelet coefficient entropy of each phase current is calculated, the sum of the wavelet coefficient absolute entropy of all the phase currents is calculated, and the largest value phase, the smallest value phase and the medium value phase of the three values are determined through comparison. According to the designed algorithm, the type and the phase of a fault which happens to a circuit where input current signals are located are judged. The algorithm relates to three parameters, and the parameters are set through a training set; model accuracy verification is performed through a test set, and meanwhile the parameters are corrected. With the method, whether a fault happens to the circuit and the type of the fault can be fast judged, and therefore good assistance effect is played for on-site dispatch personnel to fast and accurately position a fault area after the fault happens, and the security and the stability of the electric transmission line can be improved easily.

Description

technical field [0001] The invention belongs to the technical field of power system transmission safety, and in particular relates to a method for diagnosing a short-circuit fault of a power system transmission line. Background technique [0002] On the one hand, the transmission line spans a large space distance, generally tens to thousands of kilometers. On the other hand, it is exposed to the outdoors with harsh environmental conditions for a long time, so it cannot be effectively maintained. Compared with other electrical components, the conditions of the transmission line It is determined that it is the link most prone to failure in the power system. On the transmission line, the most common and dangerous fault is the abnormal connection between phase and phase or phase and ground, that is, short circuit. These faults are divided into single-phase ground short circuit, two-phase phase-to-phase short circuit, two-phase ground short circuit and three-phase ground short c...

AI Technical Summary

Problems solved by technology

However, for field practice, the system designed by this method is complex and cannot be well applied to practical applications, and there are various differences in different fields, so the method has poor versatility

At the same time, it takes a long time to identify faults, which is not conducive to the stable and economical operation of the power system

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