Estimation of 500 kV power transmission line parameters with PMU

Abstract

This work is devoted to the research of the real-time estimation of 500 kV power transmission lines parameters with PMU based on the solution of the optimization problem of minimizing the root-mean-square deviations of the specific line parameters or the sum of the modules of the correlation coefficients between the specific parameters and the sum of the squares of the voltages or currents measured at the ends of the line. Independent optimization variables are the correction factors of the measuring systems of currents and voltages. Based on an artificially simulated PMU dataset with specified Gaussian noise and systematic errors, it is shown that the use of correlation coefficients in the objective function is more effective than standard deviations. All 5 estimated coefficients turned out to be closer to the reference values. The results of calculations are obtained from the data of real PMUs for an operating 500 kV line with a length of 504.6 km. The deviation of the specific capacitive conductivity from the nominal value is 0.13%, compared with - 0.29% when using the sum of squares of deviations as an objective function.