Influence of Relative Humidity in Water Management of a PEMFC system using the Macroscopic Energetic Representation based on the Inversion Control

Abstract

Water management in a PEMFC is one of the biggest issues for the operation of the polymer membrane the cell and one the main topics of study of PEMFC systems. However in this article a mathematical model is intended for define the different static and dynamic characteristics of the energy behavior (voltage, power and relative humidity) for different input operating parameters values (current, pressure, temperature, hydrogen, oxygen and water flow rates). A new feasible graphical approach is used because of its simplicity and feasibility, consists of using the Macroscopic Energy Representation (EMR), based on the reaction action principle, taking into account the accumulation elements and leads to model the different elements of the system. This model is obtained to deduce and highlight a fuel cell energy management strategy taking into account the water activity in the electrolyte membrane, in order to avoid the inconvenience of flooding, drought and being able to achieve a desired humidity level content suitable for the implementation of this PEMFC. The simulation results show the beneficial interest of the Relativity Humidity around 100% to ensure the performance of the smooth operation. For this purpose, a control method based on inversion called the Maximum Control Structure (MCS) is used for the smooth running of this electrical system.