The Start-Up Analysis of a PEM Fuel Cell System in Vehicles

Addressing large load fluctuation in automotive applications, dynamic analysis of a polymer electrolyte membrane fuel cell system is conducted here. Operations of a comprehensive system-level control-oriented fuel cell model with all necessary auxiliary components are demonstrated and simulation results for start-up scenario are presented. It is shown that system stability is influenced by slow thermal management controls. High loads at start-up affect voltage and system efficiency adversely. Cathode inlet water levels are found to be adequate for humidification of recirculated fuel stream. Liquid water at cathode outlet is considerably higher at high current density start-ups, pertaining to water removal issues.