Simplified model for evaluating ripple effects on commercial PEM fuel cell

In this paper a simple model for evaluating current ripple effects on commercial PEM fuel cells is presented. The model is formulated starting from the Randles equivalent circuit and extending it assuming a dielectric relaxation of the material to represent dynamic processes in the frequency range typical of inverter current ripple. The proposed equivalent circuit is experimentally validated on a 14 kW commercial Morphic PEM fuel cell at the frequencies of interest. Finally the effects of current ripple on losses and fuel cell efficiency are discussed.

► Effects of current ripple on PEM fuel cells are investigated.
► The considered ripple is in the typical frequency range of power converters (inverters).
► Analytical model and impedance spectroscopy measurements are presented.
► A frequency-dependent-capacitance model is formulated.
► Higher frequencies produce lower additional losses due to ripple.