A review of power system state estimation: Techniques, state-of-the-art and inclusion of FACTS controllers

Increasing concern about system reliability and security has resulted into greater relevance of power system state estimation. The power system state estimation has broadened due to improvisations in techniques; revision of states from static to dynamic; inclusion of system components like FACTS, etc. A review of various state estimation techniques vis-à-vis dynamic state estimation techniques is presented in this work. A detailed discussion on commonly used extensions of kalman filter like EKF, UKF is provided along with a brief comparison. This paper also discusses how incorporating FACTS controller, in particular UPFC impacts the process of state estimation. In addition, dynamic modeling of UPFC is discussed.