The stationary electric field, current pattern and coupling losses in a multfilamentary, superconducting, twisted, torus-shaped wire are calculated for a torus placed in a homogeneous magnetic field increasing in time at a constant rate and parallel to the torus plane. The radius of the wire is considered to be small compared to the mean radius of the torus. An important parameter for the problem is the ratio between the twist length of the superconducting filaments and the mean radius of the torus. In the configuration considered this parameter is small. The coupling losses are approximately inversely proportional to the square of this ratio. Furthermore, for the wire to have unsaturated parts, the analysis shows that the rate of change of the magnetic field must decrease when this ratio increases.
- Magnet stability
- AC losses
Niessen, E. M. J., van de Klundert, L. J. M., van Damme, R. M. J., van Beckum, F. P. H., & Zandbergen, P. J. (1992). Coupling losses in superconducting torus-shaped wires due to applied magnetic field changes. Journal of engineering mathematics, 26(3), 395-413. https://doi.org/10.1007/BF00042742