Simulation Model for PEMFC System

There are several fuel cell system dynamic models in the literature that are specifically developed for vehicle propulsion. The simplest dynamic model of a fuel cell stack is the representation of the stack with an equivalent circuit whose operating parameters are based on the polarization curve obtained from the manufacturer data sheet at nominal conditions of temperature and pressure. An equivalent single-cell model with semiempirical equation for the fuel cell polarization curve can also be used for this purpose. 

The simplest empirical model for single fuel cell voltage as given in Equation 5.159 is 

The fuel cell performance curve can also be developed from first principles and mechanistic modeling combined with empirical relations. Since there are a number of variables in a given design of a fuel cell, a semiempirical approach seems to be more appropriate. Springer et al. (1993, 1996), Amphlett et al. (1995a, b, 1996) and Mann et al. (2000) have carried out such semiempirical models for PEMFC. 

These models were developed for single PEM fuel cell taking into account interfacial kinetics at the Pt/ionomer interface, gas-transport and ionic-conductivity limitations in the catalyst layer, and gas-transport limitations in the cathode backing. These models have been improved for dynamic simulation of fuel cell stack with additional feature on anode fuel flow and cathode flow, and membrane hydration air supply models (Pukrushpan, 2003). 

From Equation 5.154, the single fuel cell voltage E is given as 

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