Analysis of the effect of a load change on proton exchange membrane fuel cells used as a power source for autonomous underwater vehicles

This paper simulates the electrical transient behavior of proton exchange membrane fuel cell (PEMFC) during a load change using Matlab/Simulink. Since the PEMFC output voltage is easily affected by a load change and polarization losses, dc-dc converters are connected to the output of the studied PEMFC for converting the unregulated output voltage to 5-, 12-, 24- and 48-V_dc for possible applications in autonomous underwater vehicles (AUVs). Moreover, the effect of light- and heavy-load change on the voltage and current at the PEMFC and load terminals is analyzed in this paper. In addition, the effect of a load change between light- and full-load on the voltages and currents at the PEMFC and load terminals is analyzed in this study. In addition, the concept of control volume in the unsteady state mass and energy theory is applied to the fuel cell stack in order to understand the phenomenon in the cathode and anode channels that are difficult to obtain from measurements. The phenomenon includes the transient and steady state characteristics of the mass flow, pressure, temperature occurred in a PEMFC.