Robust Fusion Estimation of Asynchronous Hybrid Measurement in Power System

This paper develops a robust unscented Kalman filter (RUKF) based on unscented Kalman filter (UKF) for power system fusion estimation of asynchronous hybrid measurement. The proposed RUKF estimation method mainly solves two problems. First, the un-synchronization between PMU and SCADA measurements results in the inability to use the mixed measurements at the same time. Second, the bad data of PMU cause the reduction of filtering accuracy. RUKF achieves the synchronization of mixed measurements by calculating the measurement correlation. And a gain matrix correction method has been proposed that allows us to detect bad PMU measurements and filter them out by RUKF. Simulation results carried out on the IEEE 30-bus test system show that the RUKF can track system status more accurately and reliably than the traditional UKF and extended Kalman filter (EKF).