Three planned test blanket modules (TBMs) and 18 toroidal field coils break the axisymmetry of the ITER magnetic field. In this paper, the plasma response on these non-axisymmetric fields is studied quantitatively. For this purpose, self-consistent, three-dimensional, free-boundary equilibria of type ITER scenario 4 are computed. The resulting 3D equilibrium magnetic fields are then compared with the corresponding axisymmetric fields to which the vacuum perturbation fields are superimposed. The studies are performed for various normalized plasma pressures.
Analysis and correction of intrinsic non-axisymmetric magnetic fields in high-β DIII-D plasmas