High-Efficiency Megawatt Motor (HEMM)
The 1.4 MW High Efficiency Megawatt Motor (HEMM) is being designed to meet the needs of electrified aircraft propulsion. HEMM has a target performance of 16 kW/kg, 99% efficiency, and will have 3x lower losses and weight than current aircraft motors and generators.
The HEMM technology can be integrated with a typical aircraft cooling system and can be applied to a range of aircraft types that require megawatt-level electrical power.
New technologies must be developed to ensure the motor can produce more power per mass, while efficiently maintaining required cryogenic temperatures. Three components being built and tested are a rotating acoustic cryogenic cooler, superconducting rotor coils, and a high-performance stator.
Primary Components
HEMM’s exterior looks like a standard motor, but inside, it houses advanced technologies to maintain proper function while increasing power capability.
- Stator: Generate current with a cable made up of 5,000 hair-thin wires. Housing the rotor in a vacuum tube minimizes heat transfer between the stator and rotor.
- Superconducting Coils: Superconducting materials can carry more current than a common conductor, resulting in a higher-performing motor. The spinning coils must be kept at extremely cold temperatures (-223°C) to maintain their superconducting properties.
- Cryocooler: The superconducting rotor does not require an external cooling system, but is cooled by an integrated cryocooler. Powered by a rapid-moving linear motor, the cryocooler maintains the cryogenic temperature limit of the rotor coils.
HEMM components are undergoing individual testing and analysis. Once each component has demonstrated a high level of confidence, they can be manufactured for a test of the full-scale 1.4MW High Efficiency Megawatt Motor.
Motor Comparisons
The HEMM motor is extremely powerful and efficient for its given size (16”x42”). Though smaller than an average car engine, the 1.4MW motor is 10x more powerful.
Aircraft Level Impact
- Fuel Burn: High Efficiency Electrified Aircraft Thermal Research (HEATheR) studies have shown that increasing motor efficiency from 96% percent (state-of-the-art) to 99% (HEMM) can reduce fuel burn an additional 3%.
- Thermal System: Improving from 96% efficiency to 99% will generate 4x less waste heat.
Key Features
- Uses standard aircraft cooling systems
- Direct drive at optimal turbomachinery speeds (no gearbox)
- Can be shut off if fault occurs (wound field)
| Presentation/Paper Title | Author(s) | Document ID |
|---|---|---|
| Integrated Design | ||
| "Concept Design a 1.4 MW Inverter for Rotor Loss Minimization in a Partially Superconducting Motor" | Matthew G. Granger, Thomas F. Tallerico, Aaron D. Anderson, Justin J. Scheidler, Pete Kascak, Alex Leary, Ralph Jansen | 2022 IEEE Transportation Electrification Conference & Expo (ITEC) |
| "Combined Analysis of NASA's High efficiency Megawatt Motor and Its Converter" | Matthew Granger, Aaron Anderson, John M. Maroli, Thomas Tallerico, and Justin J. Scheidler | AIAA/IEEE Electric Aircraft Technologies Symposium 2021 |
| "Design Optimization Studies of Partially Superconducting Machines Based on NASA's High Efficiency Megawatt Motor" | Thomas F. Tallerico, Aaron D. Anderson, and Justin J. Scheidler | AIAA/IEEE Electric Aircraft Technologies Symposium 2021, 20210018004 |
| "High Efficiency Megawatt Motor Preliminary Design" | Ralph H. Jansen, Dr. Justin Scheidler, Thomas Tallerico, Dr. Peter Kascak, Dr. Andrew Woodworth, Andrew D. Smith, Dr. Rodger Dyson, William Sixel, Jerald Thompson, Erik Stalcup, Yaritza De Jesus-Arce, David Avanesian, Dr. Kirsten Duffy, Paul Passe, Gerald Szpak | AIAA/IEEE Electric Aircraft Technology Symposium 2020, AIAA-2020-3559 |
| "Electromagnetic Redesign of NASA's High Efficiency Megawatt Motor" | Thomas T. Tallerico and Justin J. Scheidler, Dongsu Lee and Kiruba Haran | AIAA/IEEE Electric Aircraft Technology Symposium 2020, AIAA-2020-3600 |
| "High Efficiency Megawatt Motor Conceptual Design" | Ralph H. Jansen, Yaritza De Jesus-Arce, Dr. Peter Kascak, Dr. Rodger Dyson, Dr. Andrew Woodworth, Dr. Justin Scheidler, Ryan Edwards, Erik Stalcup, Jarred Wilhite, Dr. Kirsten Duffy Paul Passe, Sean McCormick | AIAA Propulsion and Energy Forum and Exposition 2018 |
| Superconducting Rotor | ||
| "Methodology for Electromagnetic Optimization of a Partially Superconducting 1.4 MW Electric Machine for Electrified Aircraft Propulsion" | Justin J. Scheidler and Thomas F. Tallerico | IEEE Transactions on Applied Superconductivity, 33 (5), ASC2022-2LOr1B-01, 2023. (in review) |
| "Risk Reduction Testing of Superconducting Coils for the High Efficiency Megawatt Motor" | Dr. Justin J. Scheidler, Thomas F. Tallerico, William Torres, Wesley Miller | 2022 AIAA SciTech, 20210024896 |
| "Progress Toward the Critical Design of the Superconducting Rotor for NASA's 1.4 MW High Efficiency Electric Machine" | Dr. Justin J. Scheidler, Thomas F. Tallerico, Wesley A. Miller, William Torres | AIAA/IEEE Electric Aircraft Technology Symposium 2019, AIAA 2019-4496 |
| "Preliminary Design of the Superconducting Rotor for NASA's High-Efficiency Megawatt Motor" | Dr. Justin Scheidler | AIAA/IEEE Electric Aircraft Technology Symposium 2018 |
| "Design, Fabrication, and Critical Current Testing of No-Insulation Superconducting Rotor Coils for NASA's High-Efficiency Megawatt Motor" | Dr. Justin J. Scheidler, Thomas F. Tallerico | AIAA/IEEE Electric Aircraft Technology Symposium 2018 |
| Stator | ||
| "Select Variables Affecting Thermal System Design of a Liquid-Cooled Stator" | Andrew A. Woodworth, Andrew Smith, Ralph Jansen, Gerald Szpak | AIAA/IEEE Electric Aircraft Technology Symposium 2020 |
| "Thermal Analysis of Potted Litz Wire for High-Power-Density Aerospace Electric Machines" | Andrew A. Woodworth, Andrew Smith, William Sixel, Ryan Edwards, Ralph Jansen, Sean McCormick, Malcolm Robbie, Gerald Szpak, Paria Naghipour, Euy-Sik Shin | AIAA/IEEE Electric Aircraft Technology Symposium 2019, AIAA 2019-4509 |
| Cryocooler | ||
| "Dynamic Bellows for a Pulse Tube Cryocooler Application" | Kirsten P. Duffy, Gerald M. Szpak | AIAA SciTech Forum 2021 |
| "High Efficiency Megawatt Machine Rotating Cyrocooler Conceptual Design" | Rodger W. Dyson, Ralph H. Jansen, Kirsten P. Duffy, Paul J. Passe | AIAA/IEEE Electric Aircraft Technology Symposium 2019, AIAA 2019-4515 |