Coupling Mechanism Analysis and Decoupling Control of the Air Supply System for Fuel Cell Engine in Fuel Cell Vehicle

Pressure and mass flow control in fuel cell air supply systems highly affect the dynamic performance, reliability, and efficiency of proton exchange membrane fuel cell vehicles (FCV). However, the coupling effect between pressure and mass flow makes their control difficult and can seriously compromise the performance of proton exchange membrane fuel cells. In this paper, the optimization diagonal matrix decoupling (DMD) is proposed to avoid the occurrence of detrimental operating conditions and improve performance. This study includes data-driven modeling of the air supply system with transfer functions and the analysis of the coupling mechanisms between pressure and mass flow. The simulation results show that the proposed strategy has good disturbance rejection and low coupling between flow and pressure. Compared with conventional DMD, the standard deviation of the relative control error of flow and pressure can be reduced by 9.7%, and 14.4% in the proposed strategy. The new contribution of this paper is to reveal the coupling mechanism, which can be used to guide the design of decoupling control strategies designed for air supply systems of fuel cell engines in FCV.