The effect of parameter and measurement uncertainties on hybrid state estimation

State estimation constitutes the cornerstone of a Supervisory Control and Data Acquisition (SCADA) system, providing the operating situation of the power system in consecutive time intervals. With the incorporation of the Synchronized Measurement Technology (SMT) in the power system measurements layer, the state estimation is among the applications whose performance is improved considerably. In this paper, two sources of uncertainty that deteriorate the performance of a hybrid state estimator, that uses both synchronized phasor measurements and conventional measurements, are examined. Specifically, the measurement uncertainty and the uncertainty arising from the limited knowledge of the transmission line parameters are considered. These uncertainties are associated with the inputs of the hybrid state estimator and their effect on the overall accuracy of the process is investigated. The methodology is tested using the IEEE 14 and 118 bus systems.