Indian Journal of Science and Technology

Abstract

This work concerns the fuel cell systems modeling for their diagnosis. Particularly, we are interested in the systems based on the Nexa 1200W PEM fuel cell.To do this, a dynamic model of this fuel cell taking account of the different physical and chemical phenomena within the stack is presented. It is based principally based on Nerst equation and the use of certain parameters of the Nexa fuel cell provided by the manufacturer. Furthermore, it is accomplished bya certain number of original experimental tests (load modulation method). This model which is designed fortransportation applications contributes to the development offuel cells advanced models because it ensures the decoupling between the different internalphysical phenomena.In fact, to simplify the vehicle motor control, the established model is controlled by an average current at its input. It is especially shown that the membrane of the fuel cell model is solicited by the harmonicsgenerated by the static converters used in the vehicle powertrain powered by the 1.2 kW Nexa fuel cell model. The very important result achieved is that we cantolerate the current harmonics because the double layer capacitor realizes efficient high frequencies harmonic filtering. In this case, the systemstability is noticed. However, the results obtained confirm the use of the Nexa fuel cell system not only in powertrain, but in power electronics generally.

Keywords: Harmonics, Modeling, Nexa, PEM Fuel Cell, Powertrain, Static Converters