An Extended Kalman Filter Based Control Approach for a Telecom Microgrid

In this paper, an Extended Kalman Filter (EKF) based control algorithm is proposed for a telecom microgrid. The system loads are instantaneous constant power loads (CPLs). The proposed controller minimizes the number of current sensors in the system. The only state variable that is measured is the microgrid voltage. Without using full state feedback, the proposed controller attains the following goals. Damping of limit cycle oscillations due to CPL in the converter currents and voltages. Current sharing among the parallel connected sources. Regulation of load voltage in the event of source voltage or load power change. Since many renewable sources require a current source interface, parallel connected boost topology is chosen. The EKF based controller design is proposed and expressions for equilibrium points are derived. Stability analysis of equilibrium points is performed. Using simulation results, perfect tracking of state variables is shown both in open loop and closed loop. Further, simulation results also show the validity of the proposed controller.