Analysis and interpretation of Tcs tests of the ITER toroidal field conductor insert

The toroidal field conductor insert (TFCI) coil was tested at 46 kA in the 13 T background magnetic field generated by the central solenoid model coil. The single layer TFCI coil uses a Nb₃Sn cable-in-conduit conductor in a titanium jacket. The object of this work is to verify the data self-consistency, and to apply a thermal, hydraulic and electrical simulation to derive the strand performance in the cable. We present the results of the analysis in support of the interpretation of a subset of current sharing temperature measurements. After estimation of the n-value in the voltage-current equation, we perform the simulations using the total longitudinal strain as the only fitting parameter; the resulting value is much larger than the value expected from simple thermal contraction considerations.