Research on oxygen excess ratio control of vehicle PEMFC air supply system
Oxygen excess ratio(OER)is an important parameter that affects the output performance and safety of proton exchange membrane fuel cell(PEMFC).Controlling the OER to reach the optimal value can effectively improve the net power output of the system.To address the issue of OER control of PEMFC air supply system,a four-order model of PEMFC air supply system is established using MATLAB/Simulink platform,and the system dynamics characteristics are analyzed to verify the ef-fectiveness of the model.Three controllers are designed to control OER,including feedforward pro-portion integration differentiation(FF+PID)controller,feedforward self-adaptive fuzzy PID(FF+SF-PID)controller and sliding mode controller(SMC).In the case of input disturbance,the control effects of different controllers under fixed OER and optimal OER are compared and analyzed.The simulation results show that the SMC has shorter adjustment time and no overshoot for the control of OER,and has stronger anti-interference ability.SMC is superior to the other two controllers in dy-namic and steady-state characteristics.