Design Proposal for the ITER Feeder Busbars

Based on the functional specification by the ITER organization, CRPP developed a design proposal for the ITER magnet feeder busbar system. The magnetic field level estimated for the operation of the busbars allows the use of NbTi superconductor. The minimum superconducting cross sections and copper stabilizers are calculated based on a temperature margin of 2.5 K and a safe hot spot temperature. Based on these cross sections a busbar cable layout has been identified for each magnet feeder type and the optimization of the parameters performed with thermo-hydraulic codes. The temperature margins have been established considering both AC loss and heat exchange between the magnet coil and the busbars through the twin box joint. The rate of growth of the resistive voltage during a busbar quench was calculated to provide the input required for the design of a reliable quench protection system.