A Study on Optimization Design of Hydrogen Supply Integrated Subsystem for Multi-Stack Fuel Cells

The hydrogen supply integrated subsystem is an important part of the proton exchange membrane fuel cell system. In the multi-stack fuel cell system, the optimal design and integration of the hydrogen supply subsystem have great influence on the whole system structure. In this paper, a fuel cell hydrogen integration subsystem with two hydrogen cycle structures is established based on an optimized split-stack approach. Firstly, the matching of hydrogen subsystem is carried out on the basis of multi-stack fuel cell optimization. Then, the structure of the gas buffering and distribution device and the gas circulation device is optimized considering the gas circulation and the diversity of the equipment, and two solutions are proposed: the separate circulation structure (Structure I) and the common circulation structure (Structure II). Finally, the multi-stack fuel cell system is built by MATLAB/Simulink software and simulated under the condition of step and C-WTVC. The hydrogen consumption and parasitic power consumption of the optimized design of the hydrogen supply subsystem are compared and analyzed. The results show that the anode inlet pressure fluctuation in Structure II is smaller than that in Structure I, but the inlet common rail pipe is needed more to buffer and stabilize the pressure; nitrogen contaminates the whole anode channel space in Structure II, but its effect is negligible; and the power consumption of hydrogen circulation pump is 15.5% less than that in Structure I under C-WTVC conditions. The method of structure optimization presented in this paper can provide design guidance for high power multi-stack fuel cell system.