Feedforward fuzzy-PID control for air flow regulation of PEM fuel cell system

Abstract

Oxygen excess ratio is one of the most crucial parameters for proton exchange membrane (PEM) fuel cell system protection and performance improvement. In this study, a new fuzzy-PID controller based on feedforward approach is proposed to regulate oxygen excess ratio. To implement a feedforward fuzzy-PID (FFPID) control, a control-oriented dynamic model of PEM fuel cell is developed in MATLAB/Simulink platform including cathode and anode mass flow transients and membrane hydration dynamics model. Moreover, PEM fuel cell balance-of-plant (BOP), comprised of air compressor, humidifier, cooler, and purge valve, is also integrated into the system modeling. In order to optimize PEM fuel cell operation, such as preventing oxygen starvation and/or optimizing output power by trade-off compressor parasitic power, a FFPID controller is developed to adapt PID parameters to regulate air flow rate using on-line fuzzy logic optimization loop. A FFPID controller utilizes the reference feedforward input and the errors. Conventional PID and conventional fuzzy-PID (CFPID) are compared to validate the performance of the FFPID control method. Simulation results reveal that the efficacy of the proposed feedforward fuzzy-PID approach is proved in regulating the oxygen excess ratio and in reducing parasitic power loss.