Ways of Using Phasor Measurements in Power System State Estimation

A review of publications on using data from phasor measurement units (PMU) in electric grid state estimation (SE) algorithms is presented. Ways of including phasor measurement data in the SE problem formulation are considered based on the weighted least squares method. The advantages and drawbacks of each of the presented approaches are analyzed. Much attention is paid to the prospects of simultaneously estimating telemetric information and PMU data, and performing SE based solely on the PMU data. The computational difficulties and other obstacles that arise in using phasor measurements in performing SE are analyzed, and various ways of solving existing problems in this field are presented. It is pointed out that the accuracy of data obtained from PMU devices differs essentially from that of data obtained from classic measurement instruments. This circumstance imposes certain specific features on selecting the weighting factors for phasor measurement data in solving the SE problem. The existing approaches to determining the weighting factors for phasor measurement data, in particular, by calculating them based on available statistical data, are reviewed.