Multi source coordinated control strategy for electric hydrogen coupling isolated DC microgrid

In the isolated DC microgrid, the power deviation between the system source loads needs to be balanced by the energy storage unit, and the state of charge of the energy storage becomes the key to the long-term stable operation of the isolated DC microgrid. By analyzing the characteristics of the electro hydrogen coupling unit, a multi-source coordinated control strategy based on DC bus voltage deviation is proposed. The control strategy takes the battery as the core of voltage regulation, and realizes the coordinated operation of electricity and hydrogen by detecting the voltage fluctuation of the DC bus at the converter port, so as to maintain the power balance of the system. In order to avoid battery shutdown due to excessive charging state, a multi-source adaptive droop controller considering energy storage SoC is designed, which makes the output of hydrogen energy unit actively respond to the change of SoC, reduces the unbalanced power caused by battery SoC management, inhibits the speed of SoC approaching the boundary value, and realizes the dynamic balance of SoC. The effectiveness of the proposed control strategy is verified in MATLAB/SIMULINK.