The ITER-FEAT toroidal field structures

The magnet system of ITER-FEAT consists of 18 toroidal field (TF) coils, a free standing central solenoid, six poloidal field coils, and a set of correction coils. The TF coils are being designed to provide the magnetic field necessary to maintain plasma in a tokamak configuration with a current up to 17 MA and operate at a maximum field of 11.8 T as reported by Okuno et al. (Key Features of the ITER-FEAT Magnet System, Paper F-26, 21st Symposium on Fusion Technology, Madrid, Spain, 11–15 September 2000). The TF coil cases, which enclose the TF winding packs, are the main structural components of the magnet system. Extensive finite element (FE) analyses have been performed to investigate several design options by using 3D non-linear FE models, representing a 20° symmetry section of the TF coil magnet system. Evaluation of the results was mainly focused on the acceptability of static and cyclic stresses in the TF coil case and loads on keys/pins in the inner intercoil structures and outer intercoil structures.