探究燃料电池系统空气供给控制对能量管理策略性能的影响

Abstract This study presents a comprehensive approach to optimizing the performance of a hybrid fuel cell (FC) battery powertrain through the development of a systemic energy management strategy (EMS). The strategy is designed with two levels of management and control, aiming to enhance the efficiency, reduce hydrogen consumption, and improve the safety of the powertrain system. The first level involves an optimization-based EMS focused on efficient power distribution between the FC and the battery pack. Key to this approach is the consideration of air supply system constraints, which include maintaining safe compressor operation by avoiding the surge zone in the compressor map and ensuring the optimal range for the Oxygen Excess Ratio (OER). By addressing these constraints, the strategy not only improves the stability of the compressor but also minimizes hydrogen consumption. The second level of the strategy is on control, utilizing an adaptive PID controller to dynamically track the imposed optimal OER reference. This control layer adjusts the compressor motor voltage to achieve OER tracking, further optimizing the performance of the powertrain under varying operational conditions. The combination of these two levels results in balanced power distribution, reduced hydrogen consumption, and enhanced operational safety, particularly across different altitudes and power demands. To validate the effectiveness of the proposed strategy, two case studies are conducted: one involving a vehicle driving cycle and another using a standard aircraft mission profile. For the vehicle case, the system is evaluated at sea level, 1000 m, and 2000 m. The findings indicate that the optimal OER reduced hydrogen consumption by 2.6 % to 5.1 % at sea level, 2.4 % to 4.2 % at 1000 m, and 1.6 % to 3.0 % at 2000 m compared to constant OERs of 2.0 and 2.5. In the aircraft case, where both altitude and power demand vary over time, the results showed that the optimal OER reduced hydrogen consumption by 1.6 % compared to a constant OER of 2.0 and by 3.1 % compared to a constant OER of 2.5. These findings reveal the benefits of incorporating a systemic approach to EMS that not only enhances fuel efficiency but also ensures operational stability. At high altitudes, adhering to the optimal OER becomes crucial, as it is the only viable option to maintain efficient operation without the need to oversize the compressor, which would otherwise compromise system performance.