Test results for the high field conductor of the ITER central solenoid model coil

Two Nb 3 Sn cable-in-conduit conductor sections, left over from the winding of the ITER Central Solenoid Model Coil (CSMC), have been assembled to a sample for the SULTAN facility. The test program included dc and ac performance. The quench current, I q , of the conductor is measured up to 11 T background field, 100 kA and a broad range of operating temperature. The test is repeated for different current distribution in the conductor, obtained by altering the geometry of the bottom joint. The conductor dc performance is compared to the predictions from the strand data, deduced for homogeneous and unbalanced current distribution. The ac losses under sinusoidal field sweep are measured by gas flow calorimetry. The impact of the background field and transport current on the ac losses is explored for a number of typical operating conditions. The results indicate that the coupling loss is very small.