Anatomy of a 20 MW Electrified Aircraft: Metrics and Technology Drivers

Abstract

Development of electric, hybrid and turboelectric propulsion technologies for electrified aircraft propulsion system is essential for improving fuel consumption, reducing emissions and noise pollution, lowering maintenance costs and improving reliability of the air transportation systems. The future needs and key benefits of aircraft electrification has made it a highly persuaded common technology trend across the aerospace industry ranging from very large airplanes to small aircrafts, all alike. For very high power (20MW) propulsion system, with the inadequacies of current and near future state-of-the art of electric energy storage technologies, all electric aircraft solution faces enormous technology gaps that needs to be bridged. Advanced turbo-electric technology offers potential solutions towards successful realization of the benefits of electrification of aircrafts. However, this represent a grand challenge in many fronts to realize electric drivetrain (EDT) designs that would significantly improve fuel burn reduction, design flexibility, and operational improvements in next generation of aircrafts. This work focuses on the underlying technological elements to enable such high power turbo-electric aircraft. A preliminary study is carried out to find that to achieve the key benefits of electrifications, the ETD system efficiency has to be > 93% and the specific power density of the system is required to be > 7.5 kW/kg. Furthermore, it is found that that to achieve such system level performances, the EDT components is required to be ≥ 99% and with specific power densities > 40 kW/kg to achieve the 7.5 kW/kg target. These necessitates orders of magnitude of improvements at all technological fronts and requires radical improvement in design and integration methodologies. Major technologies and design trades for various components and system architectures are presented to provide guidelines and framework to address this grand challenge. Key results are provided to support the design study.