Requirements on melt-textured Y-Ba-Cu-O for the use in magnetic bearings or electric motors

Melt-textured Y-Ba-Cu-O (YBCO) is prepared in batch process with reproducible material properties. Functional models of magnetic bearings and electric motors were equipped with this material. From the tests of these models the requirements on further material development can be derived. The quality of a magnetic bearing can be improved by increasing the size of the superconducting domains. The current density should be in the order of 200-400 A/mm/sup 2/. Reluctance motors with output powers up to 38 kW at 77 K were constructed. Further improvements can be achieved using large superconducting domains with higher current density.