ELECTRIC-FIELD AND LOSSES AT AC SELF-FIELD MODE IN MF COMPOSITES

Studies of the current-voltage characteristics of typical superconduct ing wires under static and dynamic conditions up to 50 Hz frequency ha ve revealed much higher instantaneous local loss power densities in an external DC magnetic field than those which occur by magnetization in a transverse AC magnetic field. In this paper, the measured loss char acteristics are compared with theoretical ones derived from the critic al state model, and the self field AC losses are also estimated. Possi ble errors that can result by applying the critical state model are di scussed.