9818247179

An Electrochemical-Based Fuel Celi Model Suitable for Electrical Engineering Automation Approach

Jeferson M. Correa {IEEE Student Member) Colorado School of Mines Golden, CO United States jcorrea@ mines. edu

Felix A. Farret (Non-Member)

Federal Universily of Santa Maria Santa Maria, RS Brazil

[e-mail]

Luciane N. Canha (,Non-Member)

Federal University of Santa Maria Santa Maria, RS Brazil

Incanha @ct. ufsm.br

Marcelo G. Simoes" (IEEE Senior Member) Colorado School of Mines Golden, CO United States [e-mail] Corresponding author

Abstract - This paper presents a dynamie electrochemical model for representation, simulation and evaluation of performance of smali size generation Systems emphasizing particularly PEM fuel celi stacks. The results of the model are used to predict the output voltage, efficiency and power of FC’s as a function of the actual load current and of the constructive and operational parameters of the cells. Partia! and total load insertion and rejection tests werc accomplished to evaluate the dynamie response of the studied models. The results guarantee a better analytical performance of these models with respect to former ones with a consequent reduction in time and costs of projects using fuel cells as the primary source of energy. Additionally, this electrochemical model was tested for the SR-12 Modular PEM Generator, a stack rated at 500 W, manufactured by Avista Laboratories, for the Ballard Mark V fuel celi and for the BCS 500 W stack.

Keywords: fuel cells, automation, control, modeling and simulation.

I. INTRODUCTION

Non-polluting energy generation and other environmental issues have been driving during the last few years an inereasing demand for new energy conversion technologies. Within such perspective fuel celi (FC) systems have been showing up as a promising altemative due their high efficiency, Iow aggression to the environment, excellent dynamie response and superior reliability and durability in space, automotive and stationary applications. Especially, Proton Exchange Membranę Fuel Cells (PEMFC) are considered great altematives for distributed sources of energy. PEMFC produces water as by-product waste, operating at Iow temperatures and allowing fast start-up. PEMFC use a solid polymer as the electrolyte reducing construction, transportation and safety concems.

A FC produces electrochemical power due to the passage of a rich gas in hydrogen through an anodę and of oxygen (or air) through a cathode, with an electrolyte between the anodę and cathode to enable the exchange of electrical charges (ions). The ion flow through the electrolyte produces an electrical current in an extemal circuit or load.

Any hydrocarbon materiał, in principle, can be used as fuel independently of being gas, liquid or solid. However, these materials have to pass through a reformer to liberate the hydrogen of the carbon.