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arXiv · 2506.20096

First experimental demonstration of plasma shape control in a tokamak through Model Predictive Control

Abstract

In this work, a Model Predictive Controller (MPC) is proposed to control the plasma shape in the Tokamak à Configuration Variable (TCV). The proposed controller relies on models obtained by coupling linearized plasma response models, derived from the \texttt{fge} code of the Matlab EQuilibrium toolbox (MEQ) suite, with a state-space description of the core TCV magnetic control system. It optimizes the reference signals fed to this inner control loop in order to achieve the desired plasma shape while also enforcing constraints on the plant outputs. To this end, a suitable Quadratic Programming (QP) problem is formulated and solved in real-time. The effectiveness of the proposed controller is illustrated through a combination of simulations and experimental results. To the best of our knowledge, this is the first time that a plasma shape control solution based on MPC has been experimentally tested on a real tokamak.

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Adriano Mele, Maria A. Topalova, Cristian Galperti, Stefano Coda, TCV team, Eurofusion Tokamak Exploitation Team. 2025-06-25. First experimental demonstration of plasma shape control in a tokamak through Model Predictive Control. https://arxiv.org/abs/2506.20096

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