Control-Oriented Modeling and Analysis of Air Management System for Fuel Reforming Fuel Cell Vehicle

Abstract

With the purpose of meeting the specifically restrictive requirements of fuel reforming fuel cell vehicle, this paper brings into focus the issues of the transient operation of fuel cell systems and presents a control-oriented dynamic model of fuel cell air management system, suited for multivariable controller design, system optimization, and supervisory control strategy. In a first step, the dual analytical approach based on lumped and distributed parameter models is detailed: The partial differential equations deduced from mass/energy conservation laws and inertial dynamics are reduced to ordinary differential equations using spatial discretization and then combined with semiempirical actuator models to form the overall air system model. In a second step, a classical approach is followed to obtain a local linearization of the model. A validation of both nonlinear and linearized versions is performed by computational fluid dynamics simulations and experiments on a dedicated air system test bench. Thanks to dynamic analysis (pole/zero map), operating point impact and model order reduction are investigated. Finally, the multiinput multioutput state-space model—which balances model fidelity with model simplicity—can be coupled with reformer, stack, and thermal models to understand the system complexity and to develop model-based control methodologies.