WATER ACTIVITY CONTROL OF PEM FUEL CELL USING ENERGETIC MACROSCOPIC AND INVERSION METHODOLOGY

Abstract

This paper describes how to control water activity in a PEM fuel cell using a new graphic formalism of energy systems called Macroscopic Energy Representation (MER). This methodology allowed us to model the behavior of a PEMFC (fuel cell voltage, power and relative humidity) as a function of operating variables such as (current, pressure, temperature, flows of hydrogen, oxygen and water). The validation of the simulation results shows the importance of the influence of relative humidity RH on the PEMFC cell behavior. In addition, these variables adjusted to take account of the RH in order to obtain better performance of the operation of the FC.
For this reason, a control method based on inversion the Maximum Control Structure (MCS) used in order to ensure a relevant and adequate use of this energy system and to avoid the disadvantages of flooding and drying case, to achieve the desired relative humidity for relaxed operation of this PEMFC.