燃料电池无人机能源管理与飞行状态耦合

开展了燃料电池/锂电池（简称燃锂）混合动力无人机的能源管理与飞行状态耦合研究。综合顶层飞行任务规划与底层能源系统管理，以动力系统模型为耦合点联立能源系统与无人机运动方程，建立能源状态与运动状态耦合模型。针对燃锂混合最紧密的爬升过程，以迎角、转速和燃料电池的放电功率作为控制变量，建立了燃料消耗最小的能源管理与航迹规划耦合最优控制问题，研究不同爬升高度对最优控制过程的影响，并与模糊控制能源管理策略进行对比分析。针对大功率短时爬升和小功率长时巡航的典型任务特点，建立了燃锂最优混合问题。研究了最优的锂电池容量和燃料电池功率水平的混合量，以及爬升和巡航两阶段最优功率分配和飞行状态，分析了不同巡航目标高度对最优混合量和飞行状态的影响。结果表明：采用能源与航迹耦合的最优控制策略在给出最优功率流分配的同时，能够很好地兼顾飞行状态控制；对燃锂混合和飞行状态的综合优化可以有效地处理爬升和巡航阶段的能源需求矛盾，在给出最优燃锂混合量和飞行状态的同时，降低整个任务过程的燃料消耗。

Coupling effect of energy management and flight state for fuel cell powered UAVs

The coupling effect of energy management and flight state control of the fuel cell and battery of UAVs are investigated. Considering the top-level mission planning and the underlying energy system management, the propulsion system model is used as the coupling point to join the flight motion equation and the energy system state equation to establish the coupled model of motion state and energy state. For the climb process with high degree of mixing fuel cell and battery, the angle of attack, rotational speed, and fuel cell power are used as the control variables to study the influence of flight target altitude on the optimal control problem for the integrated path planning and energy management. The established control strategy is compared with a fuzzy control energy management strategy that only considering the state of the energy system. Based on the typical task characteristics of high-power short-term climb and low-power long-time cruise, the optimal hybrid problem of fuel cell/battery is established. The optimal hybrid of fuel cell and battery with the optimal power distribution and flight control are derived. The influence of different cruise target altitudes on optimal hybrid fuel cell/battery and flight state is analyzed. The results show that the proposed coupling optimal control strategy considering both energy system and path planning can provide a good flight state control while giving optimal power flow distribution. Considering the characteristics of long-term low-power cruise and short-time high-power climb, the optimization results of hybrid fuel cell/battery and flight state control present optimal flight state while reducing fuel consumption throughout the mission.