Tokamak reactor concepts using high temperature, high-field superconductors
Tokamak ETR and demo reactor design concepts using high-temperature, high-field oxide superconductors are described. Current densities in recently developed oxide superconductors appear at present to be very low, and it is not clear whether practical magnets for fusion applications can be developed. However, if this development occurs the potential impact on tokamak design appears large. Significant reductions in cost, complexity, and physics extrapolation could be possible by the combination of very high fields and liquid nitrogen operation. Illustrative parameters are given for an ETR device that has about the same plasma volume as TFTR. Parameters are also given for a demo device with approximately the same plasma volume as JET. If practical oxide superconducting magnets cannot be developed, a significant degree of the improvement due to high-field operation might in fact still be realized using existing superconducting materials such as Nb3Sn (Ta, Ti).
