Modeling and Control of a Proton Exchange Membrane Fuel Cell System with Alternative Fuel Sources

Abstract

The aim of this work is to study the control of the proton exchange membrane (PEM) fuel cell stack system with alternative methanol fuel. An external circulating water flow design not only plays the role of heat exchanger, but also it is the one of reactants of the methanol reforming system. The open-loop tests show that the variation of water flow causes unsteady hydrogen production at the exit of fuel processing units (FPUs) to seriously affect the stack temperature and reduce the performance of the power system. Since the reforming-integrated fuel cell system has strongly nonlinear behavior, the model-free fuzzy control technique is used to ensure the stable output regulation. On the basis of the proportional−integral−derivative (PID) configuration with one tuning parameter, the closed-loop simulation shows that the controller reliability is satisfactory when unknown inlet perturbations and loads appear.