Optimal Control of Multi-Kite Emergency Trajectories

Thilo Bronnenmeyer

Friday, May 11, 2018, 10:15

"Room 01-012, Georges-Köhler-Allee 102, Freiburg 79110, Germany"

My thesis concerns itself with optimal control for multi-kite emergency trajectories. Multi-kite systems consist of small autonomous airplanes (usually referred to as kites), that are linked to each other and to the ground by tethers and are employed in the field of airborne wind energy to generate power. The goal of this thesis is to construct a modular optimal control framework that can be used to compute optimal emergency landing trajectories. This framework includes a systematical categorization of possible emergency scenarios and the development of strategies in order to deal with each of those categories. We formalize a modular homotopy strategy to find good and feasible initial guesses for the complex non-linear multi-kite systems. We further formulate a number of different optimal control problems, each representing different emergency scenarios, and and analyze their corresponding solutions, both in terms of what physical phenomena make these particular trajectories optimal and how the optimal trajectories change when varying physical or numerical parameters. The optimal control framework is implemented within the python toolbox AWEbox.