Comparison of transmission line parameter estimation algorithms through simulated and real-field PMU data

Transmission line parameters are subject to variations caused by different factors such as weather conditions and line loading. Synchrophasors taken on both line ends through phasor measurement units (PMUs) in near-real time have brought an opportunity to identify the line impedance and admittance. Quite a few line parameter estimation approaches are available in the literature, which makes it hard to select an effective algorithm. The performance of the proposed algorithms on real-field synchrophasor data is also questionable since most of the papers have only dealt with simulated voltages and currents. In this work, a number of line parameter estimation expressions are put together, including a few modifications, and examined on both simulated and real-field synchrophasors. As a result, the most accurate line parameter estimation methods are highlighted. The positive sequence line reactances are determined through phasor data collected from a real 500 kV line with an error of around 1.5-3 %.