Modeling and Control of a High-power DC-DC Hydrogen Converter Based on DC Grid

Water electrolysis hydrogen generation is considered as a prospective solution to the problem of the renewable energy sources (RES) absorption. To expand the capacity of the high-power hydrogen production system, the hydrogen converter based on the medium-voltage DC bus (MVDCB) is a key equipment. An isolated modular converter is designed in this paper, which can achieve the high step-down ratio, electrical isolation, low output current ripple, high efficiency, and fault isolation capabilities. Considering the dynamic characteristics of proton exchange membrane water electrolyzer (PEMWE) coupled with RES, the modelling method and control strategy are studied by combining the equivalent dynamic electrical models of PEMWE. Finally, the control strategy is verified by simulation.