Model and experimental validation of a PEM fuel cell for performance, durability, signal optimisation and exergoeconomic evaluation

Abstract

In this research, experimental data and simulation models were utilised to examine the performance, durability, signal optimisation and exergoeconomic evaluation of PEM fuel cell. The work was conducted through experiments carried out on 0.5 kW and 1.2 kW PEM fuel cells, in addition to three MATLAB/Simulink models here developed. A steady state Simulink model was created for the 0.5 kW fuel cell, and a M. Script model was built for the 1.2 kW fuel cell to perform an exergoeconomic analysis, in addition to a MATLAB/Simulink model to optimise voltage, current and power signals. Model and experiments of the 0.5 kW fuel cell revealed the maximum overall system efficiency of around 47.5% at 50% of the rated power. It is recommended that the system of 1.2kW operates at a stoichiometric ratio of less than 4 to optimise the relative humidity level in the product air and avoid the membrane drying out at higher operating temperatures. The predicted hydrogen price of 1.9 $/kg will improve the exergy cost by about 15 $/GJ, which is a decrease of 12% compared with today’s price. In terms of voltage values of the Power Electronic Interface of 1.2kW, it settled the voltage at 42V with less steady state error while Nexa settled it at 38V. Both managed to settle their output voltage in less than 18 ms, corresponding to less than 0.1 s sampling period, indicating that the optimisation model here presented can be used for devices that entail swift change of load requirements.