Superconducting conductor for T-15 toroidal magnet

Design parameters and material and performance requirements are presented and evaluated for the superconducting toroidal field magnet for the next-generation T-15 tokamak reactor. The superconductor currently under consideration is a composition of an eleven-strand transposed niobium-tin conductor and two copper tubes, combined by a layer of electrolytic copper. The superconducting properties of the niobium-tin bronze matrix composites were analyzed, including critical current density, stability under plasma current flow disruption, critical temperature and field, dependence of the critical parameters on strain, reaction of the current-carrying element to a longitudinal pulsed field, and the smeared nature of the transient characteristic. Testing scenarios are described. Superconducting values were also calculated.