Modeling and Control of a Hybrid Fuel Delivery System Based on a Two-Phase Anodic Model of a PEM Fuel Cell

A polymer electrolyte membrane fuel cell (PEM FC) system for automotive applications should meet the rapid variable power demand by consuming the fuel, hydrogen. The fuel delivery system is designed to supply the hydrogen from tank to fuel cell system, and sometime re-circulate exhausted hydrogen to increase the fuel efficiency and maintain the humidity at the anode side for proper water management. The pressure in anode flow channel should track the pressure in cathode flow channel to prevent high pressure difference damage on the thin layers in cells with stable stiochiometric ratio of hydrogen. In this paper, we analyze a hybrid fuel delivery system that consists of two supply and two recirculation lines including a control valve, low pressure regulator, an ejector, and a blower. A quasi-1D two-phase transient fuel cell model is incorporated into the fuel delivery system for the design of controllers. A state feed-back controller were implemented and optimized, which is integrated with the fuel delivery and fuel cell system and be simulated to evaluate its tracking and rejection performance.