Modeling And Performance Evaluation Of A Power Electronic-based Controlled Fuel Cell System

In fuel cell applications, design of an appropriate controller and selection of an Ultra-Capacitor require a suitable model of fuel-cell-systems that can adequately represent the significant characteristics of the system. Such a model, using lumped circuit elements, was developed in this thesis via a simple method without requiring fuel cell design parameters. To validate the model, simulation results from the model were compared against the results from experimental setups and satisfactory results were obtained. Later, this model was used in order to design a controller that meets the control objectives, namely, regulation of output voltage and attenuation of load current variations at the output fuel cell system. Performance of the controller was verified by simulation. High efficiency is an indispensable requirement for fuel cell power conditioners. Finally, in view of this requirement, an analytical method was used in order to calculate power losses in the boost converter and determine factors that influence these losses. This method is helpful in understanding power loss mechanisms in power electronic converters and thus designing high efficient power conditioners for fuel cell systems.