Cable-in-Conduit Superconductors for MAGLEV Magnet Systems

A major advantage of using a Nb 3 Sn Cable-in-Conduit Conductor (CICC) for MAGLEV lies in its demonstrated capability to operate in supercritical helium. The result is a conductor component with a very high stability margin, that operates in a system with only a single phase working fluid. A secondary advantage is that no separate helium vessel is required, allowing a less complex system design. Thirdly, the working fluid temperature can be tailored to the conductor requirements, as well as to available cryosystem components, since the operating environment is not in a two phase saturation condition. This latter feature allows the CICC configuration to be directly applicable to high T c materials when they become available, because any desired operating temperature can be achieved with single phase helium, provided the operating pressure is adjusted accordingly. This paper will report on the application of Nb 3 Sn cable-in-conduit type conductors to a generic magnetic suspension system. Results imply significant advantages in using this form of conductor.