Minimum Fuel Consumption Strategy for PEM Fuel Cells

This paper proposes a proton exchange membrane fuel cell control strategy to produce the power requested by an electrical load, minimizing the fuel consumption and also providing a regulated DC bus voltage to the load. The power system consists of a hybrid fuel cell/capacitor topology, and the control objective is to follow the minimum fuel consumption points for a given load power profile. This is done by controlling the air pump voltage and regulating the fuel cell current through a DC/DC switching converter. Moreover, the design and control parameters of the output DC bus are discussed, and the calculations are adjusted to a Ballard 1.2-kW Nexa power module. Finally, the control results, fuel consumption, and fuel cell protection against oxygen starvation phenomenon are analyzed and experimentally validated, contrasting its performance with the Nexa power module internal control system.