Optimal PID plus fuzzy controller design for a PEM fuel cell air feed system using the self-adaptive differential evolution algorithm

Various control strategies for the air feed to a PEM fuel cell are investigated. Feedback and feedforward control strategies are used simultaneously in order to achieve maximum net power and prevent oxygen starvation. The control objective is to adjust the oxygen excess ratio using compressed air based on external disturbance variations. Maximum power tracking is obtained using the optimal oxygen excess ratio which is also compared to the constant oxygen excess ratio. In the feedforward strategy, a fuzzy logic controller and in the feedback a filtered PID controller is applied. The controller parameters are optimized simultaneously using a self-adaptive differential evolution algorithm. Simulation results show that the proposed technique improves the fuel cell system performance and prevents oxygen starvation by fixing the oxygen ratio at a proper setpoint.