HTS machines as enabling technology for all-electric airborne vehicles

Abstract

Environmental protection has now become paramount as evidence mounts to support the thesis of human activity-driven global warming. A global reduction of the emissions of pollutants into the atmosphere is therefore needed and new technologies have to be considered. A large part of the emissions come from transportation vehicles, including cars, trucks and airplanes, due to the nature of their combustion-based propulsion systems. Our team has been working for several years on the development of high power density superconducting motors for aircraft propulsion and fuel cell based power systems for aircraft. This paper investigates the feasibility of all-electric aircraft based on currently available technology. Electric propulsion would require the development of high power density electric propulsion motors, generators, power management and distribution systems. The requirements in terms of weight and volume of these components cannot be achieved with conventional technologies; however, the use of superconductors associated with hydrogen-based power plants makes possible the design of a reasonably light power system and would therefore enable the development of all-electric aero-vehicles. A system sizing has been performed both for actuators and for primary propulsion. Many advantages would come from electrical propulsion such as better controllability of the propulsion, higher efficiency, higher availability and less maintenance needs. Superconducting machines may very well be the enabling technology for all-electric aircraft development.

Turboelectric Distributed Propulsion Engine Cycle Analysis for Hybrid-Wing-Body Aircraft

“…The higher performance machines are intended for military applications, but prototypes for commercial machines are beginning to appear. High temperature superconducting (HTS) machines for aircraft propulsion have previously been discussed, primarily with "tube-and-wing" aircraft in mind [7,12].…”

Analysis of the microstructure of superconducting YBCO foams by means of AFM and EBSD

“…[1][2][3][4][5][6] is an important step forward to obtain large, but lightweight superconducting bulks, which will be important for several applications like the all-electric plane [7] or applications in space [8,9]. Metallic foams also play an important role as shock-absorbers etc.…”

Cryocoolers for aircraft superconducting generators and motors

“…The electrically driven propulsion system is feasible only if the electrical motors can be about the same size as, or smaller than, existing gas turbines. FIGURE 2 shows a comparison of power densities for electric motors and aircraft engines taken from data by Masson, et al [3]. The values shown in this figure represent general trends, but values for various motors and engines can vary significantly.…”

“…At present, most HTS machines use superconductors only in the rotor where DC currents are used to produce a DC magnetic field, which interacts with an AC excitation in the copper stator windings. Designs for allsuperconducting machines show typical power densities as high as 40 kW/kg for rotational speeds of about 10,000 rpm [3]. The use of HTS wire in the stator armature winding leads to significant AC losses in present YBCO materials.…”