Multi-Area Dynamic State Estimation with PMU Measurements by an Equality Constrained Extended Kalman Filter

Abstract

To achieve higher accuracy of estimated dynamic states, PMU measurements of buses in a network can be used for dynamic state estimation (DSE). However, it is difficult to coordinate the states of boundary buses in different areas when performing multi-area DSE. By using PMU measurements of buses in the network, this paper proposes an extended Kalman filter (EKF) based method with equality constraints to conduct multi-area DSE. First, a corrective strategy is proposed to estimate a corrective internal voltage (CIV) and a corrective rotor angle (CRA) of each generator with all PMUs’ measurements. The proposed corrective strategy can also ensure the consistency of the boundary buses in the multi-areas. Then, the CIV and the CRA are used to establish equality constraints for updating the dynamic states with the PMU measurements. An IEEE 30-bus system and an IEEE 118-bus system are used to validate the proposed method, with the results showing the feasibility and accuracy of the proposed method.