Transient model of dynamic power output under PEMFC load current variations

A PEMFC transient model that describes the output performance under dynamic power output situation is proposed in this research. It considers the numerical relationships among the operating parameters like gas pressure, relative humidity and heat source temperature, dynamic transport parameters like gas concentration, liquid saturation, membrane water content and temperature, and output performance. The influence of gas–liquid convection in porous layers on transient performance is also considered. Experimental data is utilized for the transient model validation. The result shows that the transient model developed in this research is able to simulate the undershoot of the output voltage, and it is proved to be able to predict the global PEMFC performance of steady state and dynamic state in the whole operating period. The average relative errors of voltage predictions are 0.47% at the steady state and less than 0.40% at the dynamic state. Furthermore, the influence of operating parameters on PEMFC transient performance is analyzed based on the developed model. The potential utilization of the transient model on the optimal analysis is discussed in this paper as well.