Transmission line positive sequence impedance estimation based on multiple scans of Phasor Measurements

In the paper the proposed algorithm for estimation of transmission line parameters is tested and evaluated. The proposed algorithm uses the weighted least square method with multiple scans of measurements derived from Phasor Measurement Units (PMUs). The network topology and loading conditions in the transmission network change continuously, which can influence the estimation of transmission line parameters with synchrophasor measurements. The case studies in the paper assess the influence of usage of multiple scans of synchrophasor measurements during sudden change of loading and network topology conditions. In the paper the presented algorithm is tested using simulated PMU measurements with and without introduced random errors. High number of measurement scans improves the transmission parameter estimation results but at the same time the calculation time of the algorithm increases. To obtain the optimal results, a compromise between the number of measurement scans and calculation time is needed.