Current distributions and AC losses in self-fields for superconductor tapes and cables

The alternating current losses in self-fields for superconductor tapes are investigated using numerical calculations. In the calculation, the current distributions and self-field losses for straight superconductors with the arbitrary sectional geometry are calculated as a parameter of current amplitude. For the 7-filamentary tapes, the losses depend on the filament configurations, which is also observed experimentally in the 7-filaments samples. In the case of cables, the values of the losses are strongly influenced by the tape arrangements. The losses for altered cables, which are composed of a number of similar tapes, are different from each other. These results suggest that the optimization of tape and cable structure, i.e. the arrangement of the superconductor cores in the cables, is useful to reduce the loss generation in the cables.