Research on Control Strategy of SMES-BESS Hybrid Energy Storage System in DC Microgrid

In recent years, the development of photovoltaic power generation technology has made it one of the main micro-sources of DC micro-grids. The energy hybrid energy storage system smoothes its power fluctuations, thereby stabilizing the DC bus voltage. Among various energy storage methods, Superconductor Magnetic Energy Storage (SMES) can store electrical energy in a long-term, high-efficiency, and non-destructive manner. It has the advantages of fast response, high power density, and high efficiency. The system can respond to different power response demands in the DC microgrid, and improve the utilization rate of renewable energy and the stability of the microgrid. A layered control strategy of bus voltage based on a DC microgrid is proposed, and the state of charge (SOC) of the energy storage unit controls the switching of the energy storage unit between different operating modes. The simulation platform was built by MATLAB/Simulink, and the effectiveness of the proposed control strategy was verified.