Description: This proposal focusses in the development of two high power density and high reliability asynchronous lift motors for Electric Vertical Takeoff and Landing (eVTOL) while being relevant to the NASA Revolutionary Vertical Lift Technology (RVLT) Project. This motors are proposed in response to NASA’s A1.06 Vertical Lift Technology for Urban Air Mobility -Electric Motor Fault Mitigation Technology request of advanced technologies supporting electric/hybrid-electric propulsion for the advance air mobility, specifically, to the area of Single Fluid Motor with High Power Density and High Reliability. The key issues in the Phase II program are the redesigning - scale down of the present highly successful Ohio State University megawatt class induction motor to, (1) optimize overall design (poles, topology, size, etc.) from 1 MW class to a 200 kW class UAM eVTOL motor as well as, (2) to operate with single fluid bearings and (3) synergistically integrate the lubrication with cooling in order to operate a single fluid and to achieve maximum power density and reliability. During this program, two full-size motors (with shaft equivalent performances) based on different electromagnetic solutions will be fabricated in order to allow a complete shaft-to-shaft testing program and an apple-to-apple comparative analyze. Both motors will develop 500 kW continuously at 5000 rpm using a proprietary single fluid & semi-evaporative cooling and lubrication method. At the end of Phase 2, both motors will be thoroughly tested on a custom built bench test.

Benefits: The innovations (related to cooling and lubrications) may be directly and immediately applied to the other area (the first area) of the A1.06 solicitations: Electric Machine/Motor Fault Detection and Fault Mitigation and Megawatt electric propulsion systems in the A1.04 Electrified Aircraft Propulsion subtopic. In addition to eVTOL, UAMs and electric passenger aircraft, NASA can benefit for many applications where lightweight power components are required such as smaller land-based motors and generators.

The results of this work can lead to various applications related to high power density rotating machines in a plethora of fields which are not traditionally electrically driven. Transportation and energy are two major relevant application areas with immediate applications for aircraft turbogenerators, aero-propulsion motors, marine propulsion and portable emergency power systems.