ABSTRACT
This chapter describes various models of polymer electrolyte membrane fuel cell (PEMFC). For preliminary fuel cell power system planning, stability analysis, control strategy synthesis, and evaluation, an appropriate dynamic model of a fuel cell system is desired. The PEMFCs dynamic behavior is inherently nonlinear, any linear model of the dynamics is only an approximation of the original nonlinear equations. A model is useful for transient response analysis and for control design by linear system techniques subject to the constraint of small perturbations. A partially linearized model of PEMFC dynamics is applied, where the partial pressures of the hydrogen, oxygen, and water in the fuel cell were each modeled as having first-order dynamics. The transfer function being investigated represents the fuel cell’s output voltage response to a perturbation of the load current, which is equivalent to its output impedance. Sensitivity analysis quantitatively characterizes the effect that each particular parameter and operating point variable of the fuel cell have on that impedance.
