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Abstract This study focuses on the control of dimethyl ether (DME) autothermal reforming (ATR) process integrated with proton exchange membrane fuel cells to provide adequate external power for an on-board reformer hydrogen vehicle. ATR reaction was made over Pd–Zn/γ-Al2O3 catalyst, which provides higher selectivity to the hydrogen due to its good oxidation and reforming activities. Catalyst activity was tested experimentally by varying the temperature. The hydrogen volume fraction is close to 45% at the optimal temperature of 400 °C. The objective of the process control scheme was to control the ATR reactor's temperature and the hydrogen production rate. A combination of the feedforward control and the closed-loop control (based on PID control) was applied wherein the DME, and air flow rates were adjusted automatically, and steam was supplied excessively to promote reactions. Due to its good oxidation and reforming activity, it had a high selectivity to hydrogen. The experimental results showed that the volume fraction of hydrogen in the hydrogen-rich gas is close to 45% at the optimum temperature of 400 °C. The control strategy could ensure that the hydrogen production rate changed with the change of fuel cell load and did not affect the temperature of the autothermal reformer. In this way, the stable operation of the reformer was realized, and the fuel cell had a sufficient supply of hydrogen.

Abstract The performance degradation of proton exchange membrane (PEM) fuel cells is inevitable in real-time application. In particular, water management issues are related to the optimization design and the stable operation of the fuel cell system. The investigation of the mass transportation of an open-cathode PEM fuel cell based on a three-dimensional numerical model is emulated using computational fluid mechanics (CFD). The unified finite element analysis for the coupled phenomena of the charge transport, mass transport, and electrochemical reactions is discussed in this work. The simulation results are observed and compared with other experimental observations and various physical fields have shown uneven distributed inside of the fuel cell due to the single-direction gases transfer strategy. Therefore, in this study, a strategy based on interchangeable anode inlet and outlet is proposed to alleviate the uneven distribution of internal physical fields. Moreover, the optimized periods of inlet and outlet exchange are studied by comparing the experimental results.

An optimal anti-lock braking control strategy using nonlinear variable voltage charging scheme for an electric-wheel vehicle is developed with aim of improving energy recovery efficiency on the premise of vehicle safety under the critical braking situation. A variable voltage charging control scheme is proposed with its operational principles to obtain maximum energy recovery as well as to balance the energy differences of each battery cell during the anti-lock braking. Given the nonlinearity of in-wheel motor, the nonlinear variable voltage charging control law is obtained on the basis of parameters fitting via experimental data. An ideal regenerative braking torque calculated by the nonlinear variable voltage charging control law is set as one of the disturbance vectors and an optimal sliding mode–anti-lock braking control strategy is developed to provide optimal hydraulic pressure for anti-lock braking system. In this manner, the torque allocation process is omitted by using a compensation control of the hydraulic braking torque. Simulation results corroborate the effectiveness of the proposed optimal anti-lock braking control strategy with higher energy recovery efficiency.