A Model Predictive Control of SMES-Battery Hybrid Energy Storage System for Voltage Regulation in DC Microgrids

摘要

Installing hybrid energy storage systems (HESSs) is a cost-effective measure to regulate the bus voltage in DC microgrids (DCMGs). This paper proposes a fast model predictive control (MPC) based voltage control and power allocation optimization for HESS. In this MPC controller, only local unit information is utilized, and the DC bus voltage can be regulated quickly by one-step prediction horizon, which enhances the transient performance of the HESS voltage control system under various disturbances. Besides, the power allocation command is optimally achieved by the residual capacity triggered activating-sequence of different ESS units by modifying the DC bus voltage reference value. Compared with the traditional filtration and PI-based control methods, the proposed method can further reduce the charging/discharging cycles and rates of the battery. Two cases are conducted to demonstrate the feasibility and superiority of the proposed method.