Phasor estimation in power transmission lines by using the Kalman filter

This paper develops a Kalman filter-based method to estimate the magnitude and phases of currents and voltages of a single-phase transmission line. Unlike common-place practices, in which phasors are estimated by using Fourier-based or least squares methods, the standard Kalman filter algorithm is used. We represent the transmission line by using a steady-state model in which the phasors of voltages and currents are considered to be in the complex d-q\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$d - q$$\end{document} domain. We then show the estimation performance of the filter-based estimator by means of a numerical simulation of a medium-length transmission line and compare the proposed method to standard methods for phasor estimation. The results presented show that the filter is highly efficient and encourages future research on the estimation of the electric parameters of transmission lines by using the proposed method. We conclude the paper by reasoning that the proposed estimation method could be used in phasor measurement devices for improved monitoring and control capabilities of electrical systems.