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arXiv · 1811.11916

Electromagnetic coupling of twisted multi-filament superconducting tapes in a ramped magnetic field

Yoichi Higashi·Yasunori Mawatari
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Abstract

We investigate theoretically the magnetization loss and electromagnetic coupling of twisted multi-filament superconducting (SC) tapes in a ramped magnetic field. Based on the two-dimensional reduced Faraday--Maxwell equation for a tape surface obtained with a thin-sheet approximation, we simulate numerically the power loss $P$ per unit length on twisted multi-filament tapes in the steady state. The current density profile clearly shows electromagnetic coupling between the SC filaments upon increasing the field sweep rate $\beta$. Although the $\beta$ dependence of $P/\beta$ for twisted multi-filament SC tapes closely resembles that for filaments in an alternating field, we show that the mechanism for electromagnetic coupling in a ramped field differs from that in an alternating field. We also identify the conditions under which electromagnetic coupling is suppressed for the typical sweep rate of a magnet used for magnetic resonance imaging.

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Yoichi Higashi, Yasunori Mawatari. 2018-11-29. Electromagnetic coupling of twisted multi-filament superconducting tapes in a ramped magnetic field. https://doi.org/10.1088/1361-6668%2Fab0d63

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