Low AC Loss Cryogenic Aluminum Conductors for Stators in Very High Speed Motors and Generators for Electric Aircraft

This SBIR proposal is submitted in response to solicitation SBIR Topic A1.04. This project relates to development of cryogenic (rotor and stator) generators required for future thin/short haul aviation or commercial transport vehicles which use turboelectric, hybrid electric, or all electric power generation as part of the propulsion system. Turboelectric, hybrid electric and all electric power generation as well as distributed propulsive power have been identified as candidate transformative aircraft configurations with reduced fuel consumption/energy use and emissions. However, components and management methods for power generation, distribution and conversion are not currently available in the high-power ranges with the necessary efficiency, power density, electrical stability and safety required for thin haul/short haul, or transport-class aircraft. Specifically, motors/generators are desired with gt;98% efficiency, specific power gt;13 kW/kg, and total power gt;200 kW. For generators, high power density can be achieved if the rotational speed is high (15,000-30,000 rpm), however low AC loss conductors are required in the stator. This can be achieved by designing the stator with a high purity aluminum ldquo;hyperconductorrdquo; at cryogenic temperatures with a cryogenically cooled superconducting rotor.nbsp;nbsp;During the Phase I we will be investigating the use of cryogenic aluminum ldquo;hyperconductorrdquo; as a low AC loss conductor for stator coils. With the development of low AC loss aluminum ldquo;hyperconductorrdquo; wire by Hyper Tech, we can achieve high speed cryogenically cooled generators with power densities over 30 kW/kg for aircraft.nbsp; During the Phase I we intend to demonstrate approaches for manufacturing aluminum ldquo;hyperconductorrdquo; strands and cables suitable for high speed machines (500-600 Hz, 15,000-25,000 rpm), and analyze the AC losses of the conductors in applied magnetic fields for developing generator conceptual designs with high speed rotors.