For a long time, efforts have been made in the world to improve the properties of coated conductors (CCs)1). As a result, remarkable progress has been made in various performances such as Ic(B-T-θ), Je, mechanical strength, and low loss.
On the other hand, there are restrictions from the tape shape, and it is difficult to fabricate versatile tapes that satisfies all various performances.
Therefore, in future material development, we should continue to develop technologies aimed at further improving various performances, and based on this knowledge, we also should design designs such as combining the necessary performance from various elements to meet the requirements of each application. CCs suitable for development projects of aircraft propulsion system are being developed.
The propulsion system we propose is a system that operates at a relatively high temperature in LN2, and a system composed of superconducting equipment elements that use CC for the cables that connect the generator and the motor are being aimed. Furthermore, we are developing a fully superconducting rotating machine (both armature and field coils are made by CCs) for generators and motors.
In the above superconducting devices, different combinations of elemental performances are required for each parts of the devices as following targets,
[Generator & Motor] Field Coil: 500A/cmw@70K, 2.5T with sufficient mechanical strength for saddle shape coil
Armature Coil: 300A/cmw@70K, 1.2T with sufficient strength for twisting and 10-filament structure
[Transmission Cable] Stacked Conductor: 350A/cmw@70K, 1.0T with sufficient mechanical strength for bending & twisting
In this presentation, the development status of CCs suitable for the element parts of each superconducting device toward the realization of a propulsion system with the above characteristics will be presented.
1) T. Izumi, Y. Shiohara, PHYSICA C, vol. 470 pp.1527-1530 (2010)
This work is based on results obtained from a project commissioned by NEDO and METI.