Rotation losses in the superconducting bearing based on magnetic gradient levitation concept

Magnetic bearings using bulk superconductors as field shaping materials have been under development for several years. The magnetic bearings need only a steel component on the rotor side for stable operation. In this system, using a bulk superconductor as a field shaping material generates a magnetic gradient that is stable against both vertical and radial displacement. Several tests were performed to better understand the loss mechanisms during rotation. Results from rotation tests using an iron rotor or a ferrite rotor indicate eddy current loss is the dominant cause of rotational losses. (C) 2001 Published by Elsevier Science B.V.