In-vessel coils in tokamak ITER.

Magnetic coils installed inside the tokamak chamber, used for additional plasma position control or ELM mitigation. The curvature of the coils follows the wall of the vacuum vessel. The in-vessel coils are hidden from the influence of the plasma behind the first wall panels and the magnetic field they generate isn’t very strong. In-vessel coils for additional stabilization are poloidal. The coils for ELM suppression are located along the chamber walls and are designed to prevent the development of damaging instabilities by means of resonant magnetic perturbations. In-vessel coils are not superconducting and in the case of the ITER tokamak will be cooled by water flowing through their interior.