Inductive heating on a NbTi CICC magnet: energy calibration and stability analysis Original Research Article

An experiment on a NbTi coiled cable-in-conduit conductor has been carried out, aimed at measuring its stability under the disturbance conditions determined by the discharge of a capacitor bank on pulsed coils, which produces rapidly varying fields, uniformly distributed over the conductor length. The energy amount actually deposited on the superconducting strands during the external field variations has been determined, on the basis of an experimental analysis of the AC losses and the results of a semi-empirical model of AC losses in saturation regime. The heating power has been taken as input for the simulation code Gandalf: a good agreement has been found between the simulated and the measured evolution of temperature along the conductor length during the inductive disturbance. Transient stability has been measured, as function of electromagnetic and thermo-hydraulic variables. A satisfactory agreement has been obtained in the stability diagrams between experimental data and the results of numerical simulations.