Plasma and Fusion Research

Volume 15, 1405078 (2020)

Regular Articles

Empirical Formulas for Estimating Self and Mutual Inductances of Toroidal Field Coils and Structures
Yasuyuki ITOH, Hiroyasu UTOH1,2), Yoshiteru SAKAMOTO1,2), Ryoji HIWATARI1,2) and Joint Special Design Team for Fusion DEMO2)
Fukui University of Technology, Fukui 910-8505, Japan
National Institutes for Quantum and Radiological Science and Technology, Rokkasho, Aomori 039-3212, Japan
Joint Special Design Team for Fusion DEMO
(Received 6 July 2020 / Accepted 16 September 2020 / Published 26 October 2020)


Self and mutual inductances of toroidal-field (TF) coils are empirically expressed by linear combinations of three coil-shape parameters: elongation, aspect ratio, and triangularity, based on their calculation results with the Neumann formula. A regression function was also obtained for calculating rough values of self-inductances of toroidal-shape structures such as a vacuum vessel in a Tokamak-type fusion reactor. An analysis for their eddy currents induced during fast discharge of TF coils is presented for showing as an application example of these formulas.


nuclear fusion, demo reactor, toroidal field coil, inductance, eddy current, fast discharge

DOI: 10.1585/pfr.15.1405078


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