Design of a Multifrequency Signal Parameter Estimation Method for the Distribution Network Based on HIpST

Abstract

The application of traditional synchronous measurement methods is limited by frequent fluctuations of electrical signals and complex frequency components in distribution networks. Therefore, it is critical to find solutions to the issues of multifrequency parameter estimation and synchronous measurement estimation accuracy in the complex environment of distribution networks. By utilizing the multifrequency sensing capabilities of discrete Fourier transform signals and Taylor series for dynamic signal processing, a multifrequency signal estimation approach based on HT-IpDFT-STWLS (HIpST) for distribution networks is provided. First, by introducing the Hilbert transform (HT), the influence of noise on the estimation algorithm is reduced. Second, signal frequency components are obtained on the basis of the calculated signal envelope spectrum, and the interpolated discrete Fourier transform (IpDFT) frequency coarse estimation results are used as the initial values of symmetric Taylor weighted least squares (STWLS) to achieve high-precision parameter estimation under the dynamic changes of the signal, and the method increases the number of discrete Fourier. Third, the accuracy of this proposed method is verified by simulation analysis. Data show that this proposed method can accurately achieve the parameter estimation of multifrequency signals in distribution networks. This approach provides a solution for the application of phasor measurement units in distribution networks.