Development of selective line detection method with single-phase earth fault for industrial 6–35 kV networks with isolated neutral with non-sinusoidal load

Abstract

This paper presents a method for determining the outgoing line with a single-phase fault for 6–35 kV networks with a  non-sinusoidal loads. The paper considers the relevance of applying the mathematical apparatus of the wavelet transform together with the traditional methods of fault location. The application of the wavelet is relevant in the problems of decomposition of non-sinusoidal current signal of outgoing lines. This is due to the loads of modern enterprises of the oil producing sector of Khanty-Mansiysk Autonomous Okrug – Yugra. It is proposed to modernize the existing algorithm for relative measurement of the level of higher harmonics. The proposed method makes it possible to determine the outgoing line by the total energy of the spectrum of higher harmonics for different network configurations.