High Power Density Dual Rotor Permanent Magnet Motor with Integrated Cooling and Drive for Aircraft Propulsion
It is estimated that flights on narrow-body aircraft are responsible for nearly half of aviation-related greenhouse gas (GHG) emissions. A decarbonized, narrow-body aircraft with electrified propulsion would provide the greatest impact on GHG emissions from a single aircraft type. ARPA-E seeks to mitigate the growing environmental burden associated with commercial air travel at minimum economic cost by developing elements of an ultra-high efficient aircraft propulsion system that uses carbon neutral liquid fuels (CNLFs). It is anticipated that the developed lightweight and high-efficiency all-electric powertrains will find direct application in the emerging urban air mobility, unmanned aircraft aerial vehicle, and select regional aircraft markets. These markets are likely to be the first adopters before the technology scales to a single-aisle aircraft.
Project Innovation + Advantages:
Advanced Magnet Lab (AML) seeks to develop high-power density permanent magnet motors. When coupled to an integrated SiC (silicon carbide) drive, these motors will enable an overall specific power beyond 12 kW/kg. The proposed concept relies on (1) the tight integration of a high-power density dual-rotor permanent magnet rotor based on "continuous flux directed" magnets (PM-360TM) currently under development at AML, (2) high-power density SiC power converters, and (3) a shared closed-loop cooling system rejecting the heat in the propulsion ducted fan air stream. The proposed motor is based on a dual-rotor configuration using permanent magnets forming ideal Halbach arrays (a permanent magnet arrangement that creates a stronger field on one side and reduces the field on the other side to near zero) allowing for high magnetic loading without the need for iron. Integrating the motor and power converter will enable very high-power density, which is paramount in aircraft application.
The ASCEND program has the potential to accelerate innovations and cause disruptive changes in the emerging electric aviation field.
The program will further enhance U.S. technology dominance in the field of high-performance electric motors for hybrid electric aviation. Electrified aircraft architectures can increase reliability by increasing redundancy.
An all-electric propulsion system operating on CNLF would have net-zero emissions and be much quieter for passengers and people in the vicinity of airports.
By targeting propulsion system efficiency and specific power improvements, CNLF-powered, zero-net emission aircraft will be capable of a longer range and reduced fuel cost, making them economically more attractive.