Hybrid Aeronautical Propulsion: Control and Energy Management

In this paper, a control strategy for energy management of a parallel hybrid electric UAV (Unmanned Air Vehicle) powertrain is presented. A Simulink-based model of the system is first presented, consisting of an internal combustion engine, a gearbox (which includes a planetary gear and a continuously variable transmission), an electric motor (which can also work as a generator), an electric drive (Inveter) and a Li-Po battery pack. The proposed control strategy consists of a quasi-real-time iterative algorithm based on Dynamic Programming, which allows to optimize power management and torque-split of the powertrain with final state constraints on state variable. Aim of the study is to investigate new flight capabilities that derive from the use of a hybrid architecture, e.g., silent mode using only electric motor (useful for military and civil purpose), and the capacity of reducing fuel consumption. Simulation studies are performed, based on data of an existing UAV and a real flight mission.