Control Strategy for Starter Generator in UAV with Micro Jet Engine

This paper proposes control strategy of a starter generator connected to a jet engine for an unmanned aerial vehicle system. Thrust is generated by both the jet engine and propellers which are powered by the jet engine through the starter generator. A flight range can be extended since energy density of the jet engine in the developed system is higher than battery energy density in the conventional system. Moreover, the starter generator directly connects to the jet engine and rotates at high speed for miniaturization. The proposed control strategy achieves the starting, the powering and the cooling operations with the starter generator. It is confirm through an experiment of a 3-kW prototype, that the prototype system achieves the maximum conversion efficiency of 92.7%. The minimum generator current THD is 16.5% at 70000 r/min. Further, the exhaust nozzle temperature is controlled within the maximum deviation of 2% regarding to the command value in study state.