A successful demonstration of real-time, model-based control of the plasma current density profile has been made in JET. The safety factor profile was reconstructed using magnetic and polarimetric signals. Various predefined q-profile targets have been reached—in the least square approximation—using lower hybrid current drive as the only actuator, with a feedback control loop using the measurements from five fixed normalized radii.
Combined magnetic and kinetic control of advanced tokamak steady state scenarios based on semi-empirical modelling