Energy Management Strategy for Fuel Cell Uncrewed Aerial Vehicles Considering Comprehensive System Operating Cost

Energy management strategy (EMS) is one of the key technologies for performance optimization of fuel cell uncrewed aerial vehicles. However, the traditional EMS considers only energy consumption in optimizing the operating economy and ignores the cost caused by source degradation, which usually results in poor operation economy regarding total operating cost in long-term operation. In addition, to achieve the global optimization goal, most of the current EMSs can only be applied offline. To address these issues, this article first establishes a comprehensive system operating cost model, by accounting for fuel consumption, equivalent fuel consumption and power supply degradation. Then, it adopts Pontryagin's minimum principle (PMP) to determine the optimal EMS. In particular, to realize the online optimization, the costate variable of the proposed method is updated in real time according to the state-of-charge (SOC) of the battery. Finally, the hardware-in-the-loop (HIL) platform is built to verify the effectiveness of the proposed EMS. The results show that the proposed strategy has approximate global optimization ability, and compared with the equivalent consumption minimization strategy (ECMS), under the traditional and emergency flight conditions, it can reduce the system operating cost by 16.62% and 27.21%, respectively, and decrease the fuel cell operating stress by 16.29% and 36.45%, respectively. Besides, the proposed strategy can effectively maintain the battery's SOC.