Dynamic modeling and comprehensive analysis of proton exchange membrane fuel cell systems with complete auxiliary system

Abstract

Proton exchange membrane fuel cells are gaining attention as sustainable energy options due to their high efficiency and low emissions. However, the complex interaction of integrated auxiliary equipment poses challenges in achieving efficient and flexible system operation. To this end, this paper establishes an integrated mechanism of electrical, thermal, and humidity interactions in the fuel cell system, accounting for auxiliary energy consumption. Based on it, the steady state and dynamic flexibility of the system are investigated. Moreover, to analyze the changing law of energy consumption and system efficiency, the system's operating conditions were enumerated by varying the input variables, such as compressor voltage, humidification power, and coolant mass flow rate. Simulation results and comparative analysis indicate that appropriate load regulation and high-temperature operation significantly enhance the system's flexibility. With the increasing temperature at constant current, the energy consumption of the compressor increases by 0.6–4 %, whereas the proportion of cooling fans drops by 3–6 %. Moreover, although operating at high temperatures enhances the system's flexibility and load tracking capability, it also lowers its net efficiency by around 1 %. This research provides insights into improving flexible adjustment capability and efficiency of fuel cell systems, offering practical guidance for their application and development.