Parameter analysis of PEM fuel cell hysteresis effects for transient load use

Laboratoire de Génie Électrique de Paris (LGEP)/SPEE-Labs, SUPELEC, Univ Paris-Sud, Univ Pierre et Marie Curie Paris 6, CNRS (UMR 8507), 11 rue Joliot Curie, Plateau de Moulon, 91192 Gif-sur-Yvette Cedex, France

^a e-mail: olivier.bethoux@lgep.supelec.fr

Received: 29 June 2010
Revised: 17 December 2010
Accepted: 23 March 2011
Published online: 18 May 2011

Abstract

This paper focuses on the hysteresis effect of the polarization characteristics of a polymer electrolyte membrane fuel cell (PEMFC), mainly due to the compressor-air supply system dynamics. Indeed in PEMFC/ultracapacitor hybrid vehicles, fuel cells can be used to supply the low frequencies of the power demand only. First, the different parts of a FC system are described and modeled in order to analyze the transient stack performance decrease and to identify its main influential factors for automotive applications. Then, apart from humidity and temperature variations, each phenomenon is dynamically described, leading to a complete mathematical model based on macroscopic component parameters. Thus, an analytical model based on this set of equations enables us to draw the static voltage versus current FC characteristics. Furthermore, the hysteresis effect on the V-I curve, which still occurs during low dynamic responses, is shown while temperature and humidity are kept constant. Finally, dynamic responses of the Ballard PEMFC Nexa 1200 W generator are analyzed, and detailed experimentation and simulation are carried out for a large magnitude sinusoidal waveform at different frequencies.