Coordinated control strategy of electric-hydrogen coupled energy storage DC microgrid considering hydrogen storage state and DC bus voltage stability

To address the issues of bus voltage fluctuations and state of hydrogen (SOH) limit violations in electric-hydrogen coupled energy storage DC microgrids, a coordinated control strategy for electric-hydrogen coupled energy storage DC microgrids considering SOH and DC bus voltage stability is proposed. Firstly, a droop control strategy based on fuzzy algorithm is used for hydrogen energy storage system (HESS) to dynamically optimize the output power of HESS by comprehensively considering bus voltage fluctuations and SOH. Secondly, a control strategy based on analogous virtual synchronous generator (AVSG) is utilized for battery energy storage system (BESS) to simulate the charge-discharge characteristics of capacitors, so as to optimize the dynamic performance of DC bus voltage. Finally, considering the amplitude of bus voltage fluctuation, the operation modes of HESS and BESS are controlled to further coordinately optimize the stability of DC bus voltage. A simulation model of the electric-hydrogen coupled energy storage microgrid is built on the Matlab/Simulink platform to verify the effectiveness of the proposed strategy. The test results show that the proposed coordinated control strategy can improve the stability of DC microgrid bus voltage and alleviate the overcharge and overdischarge of the hydrogen energy storage system under source-load fluctuation scenarios.