Integrated High Frequency Electric Propulsor for Turbo-Electric Aircraft

We propose the development of a high efficiencynbsp;integrated electric turbofan directly driven with anbsp;high frequency, air-core synchronous motor. If the projected efficiency and specific power are achieved, this technology cannbsp;increase the viability ofnbsp;turbo-electric airplanes for commercial air transport, leading to significantly lower carbon emissions and fuel use. The key innovation is the use of high fundamentalnbsp;frequenciesnbsp;and a mostly air-core electromagnetic architecture. The aerospace industry employs 400 Hz lsquo;acrsquo; to keep component weights low. Hinetics is planning to introduce products that push these frequencies up by an order of magnitude. The machine is transformed from the traditional metal-intense design to a composite and silicon-intense design. The new architecture is projected to improve machine power density by a factor of two over current best-in-class machines, with simplifiednbsp;air cooling, while achieving 98% efficiency. Additionally, the radially thin geometry, with self-pumped air cooling, lends itself nicely to integration within a ducted turbofan. A proof of concept high frequency MW scale motor has been developed by the University of Illinois under a NASA funded project. The design leverages recent advances in Wide Band-Gap (WBG) power electronic devices to obtain anbsp;high fundamental frequency while keeping current and voltage harmonics low. Hinetics LLC will build on this technology to develop an integrated electric tail-cone propulsor for commercial transport aircraft.nbsp; Computer modeling in thenbsp;SBIR Phase I projectnbsp;has confirmed thatnbsp;the high frequency motor can be tightly integrated with a propulsion fan at the scale of NASA#39;s STARC-ABL airplane concept and achieve high efficiency (2 points higher than best-in-class) whilenbsp;retaining cooling andnbsp;power-to-weight advantages. In Phase II, Hinetics would like to validate this with a hardware demonstration, and build partnerships with Tier I suppliers to commercialize the technology.nbsp;