Hybrid Energy Storage Control Strategy for a DC Microgrid With Multiple Energy Sources

To overcome the intermittency and fluctuations of renewable energy in isolated DC microgrids, and enhance their anti-interference and absorption ability, a hybrid energy storage control strategy for multi-energy sink DC microgrids is proposed. The rapid response capability of the battery is used to stabilize the short-time power shortages in the microgrid and maintain bus voltage stability. The virtual synchronous generator control method is introduced into the hydrogen storage control strategy to enhance system inertia, fully leverage the high energy density advantage of hydrogen storage, and provide long-term energy supply to the system. The hybrid energy storage control technology, including electrochemical energy storage and hydrogen storage, is adopted to enable dynamic power distribution. The dynamic behavior of the system is described by constructing state equations and stability analysis; additionally, upper-layer power storage control and flexible storage shutdown strategies are employed to extend the service life of the energy storage system. Through simulation analysis, the control strategy effectively reduces bus voltage overshoot by about 3.9%, which enhances both the system's ability to absorb new energy and its immunity to external interference.