UAV Power Management, Generation, and Storage System Principles and Design

Abstract

This paper discusses the recent progress of a multi-year project investigating the concept of an unmanned aerial vehicle (UAV) being partially powered by the natural environment the drone will encounter along its flight path. This UAV flight is achieved using power generation, management, and storage systems. The aircraft's improvement in sustainability, or endurance, is the main benefit of this design as it harvests energy from the environment available to it, and also using the potential of replacing some of the UAV structure with the structure of the power storage devices to reduce parasitic weight. These UAV enhancements could have many beneficial applications for a modern technological society. Applications in defense are numerous, as a highly sustainable aircraft can provide longterm surveillance over essential targets. Also, weather monitoring can benefit immensely from a highly sustainable drone, as these drones will be able to follow weather patterns as they develop over time and achieve real time updates. The power generation comes from three sources: flexible solar panels, thermoelectric generators, and vibration induced power generation motors (installed in power pods or inside the wing) that are excited by either atmospheric gusts or wing flutter. These forms of AC and DC current will be combined into usable energy for the UAV energy storage devices. Utilizing these forms of energy should in theory greatly extend the flight time of the UAV as it will continually cycle through these different forms of energy throughout the day and night. The flexible solar cells will be either attached onto the wing or replace the wing upper skin structure and take in the energy from the sun during the day, outputting straight DC current. The vibration induced power generation devices are comprised of DC motors attached to leaf springs and a gear/rack mechanism that oscillate from the vibrations of the wings to spin the motor shaft and generate AC power. The thermoelectric generators will generate energy from heat flux across the hot and cold plates of the power management system and the solar cells. All these sources are combined into a single power output via the power management system (PWMS). The PWMS is based off a hybrid power design, where the input sources are combined into a single stable DC output in which lithium polymer (LiPo) batteries or graphene supercapacitors can be charged and discharged into the UAV electric motor driven propeller load.