PhD presentation by Arne Hinz

Wednesday, April 6, 2022

Via video stream. Dial-in data are available by e-mail. Please register at



5:00 p.m. [Time zone Berlin] Arne Horst Otto Hinz, M. Sc.

"Electrical Propulsion Systems for Civil Transportation Aircraft"

International regulations increasingly constrain, among others, aviation´s greenhouse gas and pollutant emissions. Ultimately, the aviation industry has to achieve climate-neutrality. To accomplish this goal, a variety of options is under investigation. This includes aircraft operation on synthetic fuels, batteries and hydrogen together with enhancing jet engine technology as well as hybrid and full electric propulsion schemes. Recent approaches to electrify civil transportation aircraft apply separated power and thrust generation. In case of large airplanes, this necessitates high-voltage onboard grids for power transfer. Thereby, heavy wiring increases the electric propulsion system´s weight. Further, high-voltage requirements exacerbate the sensitivity to cosmic ray effects while there are limited advantages in powertrain design despite lighter cables. Hence, superconductive components are proposed for electric propulsion systems in aviation to mitigate the voltage requirements. However, these components suffer from the low mechanical strength of superconductors and heavy cooling systems. In reaction to the challenges in the state of the art, this thesis proposes the electrical engine concept; a new modular full-electric drivetrain topology built on integrated power and thrust generation in concentrated entities, which enables multi-megawatt propulsion systems without high voltages and superconductors. To assess the potentials and limitations of the electrical engine concept, the aircraft ATR72-600, Airbus A320neo, and Airbus A350-900 are retrofitted based on a holistic electrical engine model covering the energy-conversion path from fuel tank to propulsor shaft, thermal management, environmental conditions, and mechanical engine configuration. In this context, prospective conventional engines serve as benchmark for the respective electrical engine layouts as effects on aircraft level remain unconsidered. In addition, a superconductive and non-superconductive electrical engine variant applies to the respective aircraft to examine the potential of high-speed switched reluctance machines in comparison to a best-case superconductive electrical machine. The results reveal that an electrical engine competitive with prospective turboprop engines requires moderate improvements in weight and size while competing with a prospective turbofan engine constitutes a major challenge. Superconductive electrical machines are supportive in this regard, but have limited effect.

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