Conceptual approach to the ultimate low AC loss YBCO Superconductor

Wide tapes of YBCO coated conductors make minimization of ac loss very difficult. Subdivision of the tape into narrow filaments does not provide complete transposition when twisted and current sharing is not equalized due to inductance differences. For ac power applications operating near 400 Hz for military aircraft power systems, equal inductance filaments and short twist pitch are very important to loss minimization. A fully transposed YBCO tape that approximates a Rutherford cable has been conceived to minimize ac loss at high frequency. Retention of optimal texture of YBCO in edge turnaround regions and filament crossovers in the Rutherford tape is essential.