Investigation of error of express estimation of total harmonic distortion current and voltage with frequency deviation in electric network

Abstract

This article describes the question of monitoring the non-sinusoidal mode of power parameters in electrical networks. The present study focuses on the method for estimating the degree of non-sinusoidal mode of power parameters of electrical networks. The objective of this study is to determine the operability and applicability of this method in conditions of frequency deviation of the supply network. The method of express estimation of the total harmonic distortion, which does not require the use of Fourier transform for select higher harmonics of voltage or current, is considered. The possibility of using a simple rectangular window function for implementing this method is considered. The results of the investigation of the operability of this method in the conditions of deviation of the frequency of the fundamental harmonic using a rectangular window function are given. Recommendations are proposed to improve the accuracy of the estimation by shifting the window function relative to the time axis of the signal. The results are confirmed by a series of computational experiments with different frequency deviations in the supply network