A Novel Energy Management Strategy Based on Minimum Internal Loss for a Fuel Cell Unmanned Aircraft Vehicle Hybrid Power System

To improve the durability and efficiency, a novel energy management strategy (EMS) considering internal loss of fuel cell unmanned aircraft vehicle (UAV) hybrid power system is proposed. First, the equivalent circuit model of the hybrid power system is established to calculate its internal energy loss. The hydrogen consumption of fuel cells and the discharge behavior of the battery can be regarded as energy consumption. Then, the total energy consumption of system is used as the first cost function, and the average efficiency of the system is considered as the second cost function. And the Pontryagin's minimum principle (PMP) control strategy is applied to achieve optimization of system cost function. Finally, the output power of the fuel cell system is controlled by solving the cost function to realize power distribution. A real-time experimental hardware platform is built to compare the superiority between the proposed EMS and traditional equivalent hydrogen consumption minimum strategy (ECMS). The experimental results indicate that the proposed algorithm can reduce the equivalent hydrogen consumption of the system by 13.6%, the internal energy loss of fuel cell by 21.8%, and the power supply stress of fuel cell by 49.1%, which can extend the lifetime of the fuel cell. Besides, the proposed strategy can effectively improve the operation efficiency of the system and maintain the battery SOC.