Assessment of PEM Fuel Cells-Based DC/DC Power Conversion for Applications in AUVs

This paper assesses the behavior of electrical output for a Ballard Mark V 35-cell 5 kW PEMFC (proton exchange membrane fuel cell) stack-based dc-dc power conversion for applications in autonomous underwater vehicles (AUVs) under load changes. Since the fuel cell produces dc output voltage that is unregulated, pulsewidth modulated (PWM) dc-dc converters are connected to the output of the studied fuel cell for converting the unregulated voltage into a desired voltage level. The fuel cell model includes the double-layer charging effect, gases diffusion in the electrodes, and the thermodynamic characteristic. Moreover, PWM dc-dc converters are assumed to operate in continuous-conduction mode (CCM), and the compensator is designed with voltage-mode control. The models of the study´s fuel cell and PWM dc-dc converters have been implemented in a Matlab/SIMULINK™ environment. The results show that the output voltages of the studied PEMFC connected with PWM dc-dc converters during a load change are stable.