Enhanced power generation of airborne wind energy system by a foldable aircraft

This paper introduces a novel approach to improve the energy efficiency of a Ground-Gen airborne wind energy system (AWES) by changing the airborne platform’s configuration. This research presents modeling and trajectory optimization approaches of an airborne platform during energy generation and recovery phases to improve net energy gain throughout a cycle. We first develop the flight dynamics of an AWES based on a conventional glider, as well as its power generation and consumption models, where the ground component is a motor/generator system that portrays a DC machine’s electric performance. An optimal control problem is then formulated to search for an optimal trajectory to maximize energy harvesting during the generation phase and minimum energy consumption during the recovery phase. In the end, the improvement of net energy gain and time reduction of the recovery phase by morphing the wing shape during the recovery phase is justified by comparing the simulation results between the folded wing model and the one using conventional glider geometry.