Additional A.C. Losses Due to Alternating Magnetic Field Component Longitudinal to Strand Axis in the Armature Winding of Fully Superconducting Generators

The armature winding of fully superconducting generators will be constructed by multiply-stacked cables of multifilamentary superconducting strands. In the superconducting cable exposed to an alternating transverse magnetic field, additional a.c. losses(called as longitudinal losses) are generated by field component longitudinal to the strand, because the angle between the axes of the strand and the final cable changes spatially with periods of cabling pitches. The longitudinal losses depend upon the structure of the cable, the direction and pitch in each level of cabling and so on. The additional losses are evaluated in electromagnetic environments of the armature winding. The structure of the cable is discussed to minimize the total a.c. loss under a stability condition.