Stabilizing elongated plasmas using extremum seeking: The ITER tokamak case study

Abstract

In this paper we propose a model-free approach to stabilize vertical unstable plasmas in tokamak devices. The approach relies on the extremum seeking algorithm and on averaging theory to bring to zero the motion of the plasma along the unstable mode, hence achieving the stabilization of its vertical dynamic. The effectiveness of the proposed approach is shown by means of simulations. To this aim, the proposed model-free vertical stabilization system is included in the magnetic control system of the ITER tokamak to consider relevant operational scenarios.