High Power Density Motors/Generators for Single and Double Aisle Passenger Aircraft using Multifilamentary High Purity Aluminum Coils at 20K

Cutting-edge research in aeronautics is needed to overcome technology barriers and challenges in developing net-zero carbon emissions from aviation by 2050, one of the environmental goals articulated in the White House’s U.S. Aviation Climate Action Plan, and aggressive innovations will be required to reach this goal through development of hybrid-electric machines for aircraft propulsion used for direct-drive propulsion of fans or propellers or as generators, turboprops, or turbofans. High power density propulsion motors are a driving factor for aircraft electrification especially for the larger single and double aisle passenger aircraft. In order to achieve the goal of > 25 kW/kg, it is important to have both stator and rotor high performance and probably both cryogenic. NASA has been advocating the use of all-superconducting rotating machines for electric propulsion. The problem is high AC in the stator. With lower AC losses, High Purity Aluminum (HPAL) Composites configured as multifilamentary wire and cables can out-perform superconductors above 100 Hz for some rotating machine targets. We propose in this project to develop and demonstrate stator coils using multifilamentary, low AC loss, HPAL strands for 20-25 K operation. The use of HPAL low AC loss stands will facilitate aircraft applications in the 1 to 20 MW range enabling high power density motors and generators in the 35-45 kW/kg range, with efficiencies in the range of 99%. During a Phase II effort we will fabricate and characterize HPAL stator coils in an existing 100 kW motor test bed. liquid hydrogen makes an obvious candidate for a thermal sink in the aircraft; the demonstration stator coils will be cooled using liquid and gaseous helium. After the Phase II effort, the technology demonstrated will create both a technical and business pathway for introduction of motors which include our HPAL composite cryogenic conductor for single and double aisle passenger aircraft.