Transportation is a leading source of green-house gas emissions, with aircraft contributing to 10% of the CO₂ emissions at 900 million metric tons of CO₂/yr. Employing electric aircraft drivetrains would greatly diminish CO₂ emissions. However, implementation of all-electric, hybrid, and turboelectric propulsion systems does present many difficult challenges in regards to power capability, specific power, and specific energy. Superconducting power transmission and cryogenic machines have unique properties that can help overcome these challenges. Superconducting power transmission has no ohmic losses, can enable practical solutions for lower transmission voltage, and utilizes ultra-small and ultra-lightweight conductors. Cryogenic machines utilizing superconducting wire possess very high efficiency and can operate at large current densities. This presentation provides analysis of cryogenic/superconducting technologies for electric aircraft drivetrains and studies mass and heat loss scaling laws (0-20 kA) for various components of the electric drivetrain: such as metal conductors (Cupanol, Al 99.999% ‘hyperconductor’), busbars, current leads, metal/superconducting T-joints, high temperature superconducting (HTS) cables (MgB₂, YBCO), and cryoflex tubing. An analysis of a 40 MW power drivetrain system will be shown, and the three technology options for the power transmission cable are compared: YBCO, Al 99.999% pure, and Cu_0.15Al_0.85 Cuponal™.

Acknowledgement Statement: This work was supported by NASA #80NSSC19M0125 as part of the Center for High-Efficiency Electrical Technologies for Aircraft (CHEETA), the Air Force Office of Scientific Research (AFOSR) LRIR #18RQOR100, Air Force Research Laboratory Aerospace Systems Directorate (AFRL/RQQM), and the National Academies of Sciences, Engineering & Medicine.

Figure Caption: Power Distribution System component weight & heat specified @ 0 – 20kA for three cable technologies: Cu-Al at 294K, 99.999% Al at 20K, HTS superconductors YBaCuO, MgB2 at 20-65K

Keywords: electric aircraft drivetrains, HTS, sustainability, cryogenics