Integrated Magnetic and Kinetic Control of Advanced Tokamak Scenarios Based on Data-Driven Models

D. Moreau, F. Liu, J.R. Ferron, D.A. Humphreys, E. Schuster, M.L. Walker, J.F. Artaud, J.E. Barton, M.D. Boyer, K.H. Burrell, S.M. Flanagan, J. Garcia, P. Gohil, R.J. Groebner, C. Holcomb, A.W. Hyatt, R.D. Johnson, R.J. La Haye, J. Lohr, T.C. Luce, R. Nouailletas, J.M. Park, B.G. Penaflor, W. Shi, F. Turco, W. Wehner, and ITPA-IOS group members and experts

IAEA Fusion Energy Conference

San Diego, California, USA, October 8-13, 2012

Abstract

The first real-time profile control experiments integrating magnetic and kinetic variables were performed on DIII-D in view of regulating and extrapolating advanced tokamak scenarios to steady state devices and burning plasma experiments. The integrated model-based approach that was used is generic and is being developed under the framework of the International Tokamak Physics Activity for Integrated Operation Scenarios. Device-specific, control-oriented models were obtained from experimental data and these data-driven models were used to synthesize integrated magnetic and kinetic profile controllers. Closed-loop experiments were performed for the regulation of (a) the poloidal flux profile, Ψ(x), (b) the inverse of the safety factor profile, ι(x)=1/q(x), and (c) either the Ψ(x) profile or the ι(x) profile together with the normalized pressure parameter, βN. The neutral beam injection (NBI), electron cyclotron current drive (ECCD) systems and ohmic coils provided the heating and current drive (H&CD) sources. The first control actuator was the plasma surface loop voltage or current (i. e. the ohmic coil), and the available beamlines and gyrotrons were grouped to form five additional H&CD actuators: co-current on-axis NBI, co-current off-axis NBI, counter-current NBI, balanced NBI and total ECCD power from all gyrotrons (with off-axis current deposition). The control method was also applied on simulated ITER discharges using a simplified transport code (METIS).