A Novel Extended Power Supply Time System for Unmanned Aerial Vehicle

This study focuses on improving flight duration in unmanned aerial vehicles (UAVs) by enhancing battery utilization and proposes an extended power supply time (EPST) system based on the lithium-ion battery (LiB) and the lithium-ion capacitor (LiC) for UAV power system. The proposed system connects two energy storage elements using a buck-boost converter, with the LiC on the input side and the LiB on the output side of the converter. A novel control strategy is developed to improve the UAV's flight duration by extending the proposed system's power supply time (EPST). This strategy utilizes the LiC to provide additional energy to the load once the LiB is depleted. Moreover, the flight duration is further extended beyond what is achievable by the LiB's extra energy alone, thanks to a phenomenon called concentration polarization. The proposed EPST system is validated through hardware experiments. The results demonstrate that the EPST system significantly enhances LiB utilization and prolongs the UAV's flight duration. Specifically, the hovering flight duration is improved by 95.6%, while the durations for hovering and changing altitude conditions are increased by 27.7% and 27.2%, respectively.