Tape-Width Dependence of AC Losses in HTS Cables

Analytical calculations are performed to determine the ac superconductor hysteretic loss of a monolayer cable composed of multiple tape-shaped superconductor wires. The dependence of loss on tape width for given gaps between the tapes and given total critical current shows a broad loss minimum. The appearance of a minimum is interpreted in terms of a ldquogap effect:rdquo the loss associated with each gap. The calculations indicate that from the perspective of decreasing total ac loss, there is little advantage to reduce tape width below about 4 mm.