Development of ITER-Relevant Plasma Control Solutions
at DIII-D
D.A. Humphreys, M. Bakhtiari, J. Blair, J.R. Ferron, Y. In, G.L. Jackson, H. Jhang, R.D. Johnson, J.S. Kim, R.J. La Haye, J.A. Leuer, B.G. Penaflor, E. Schuster, M.L. Walker, H. Wang, A.S. Welander, D.G. Whyte
IAEA Fusion Energy Conference
Chengdu, China, October 16-21, 2006
Abstract
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The requirements of the DIII-D physics program have led to the
development of many operational control results with direct relevance
to ITER. These include new algorithms for robust and sustained
stabilization of neoclassical tearing modes (NTM) with electron
cyclotron current drive (ECCD), model-based controllers for
stabilization of the resistive wall mode (RWM) in the presence of ELMs,
coupled linear-nonlinear algorithms to provide good dynamic
axisymmetric control while avoiding coil current limits, and adaptation
of the DIII-D Plasma Control System (PCS) to operate next-generation
superconducting tokamaks. Development of integrated plasma control, a
systematic approach to model-based design and controller verification,
has enabled successful experimental application of high reliability
control algorithms requiring a minimum of machine operations time for
testing and tuning. The DIII-D PCS hardware and software and its
versions adapted for other devices can be connected to integrated
plasma control simulations to confirm control function prior to
experimental use. This capability has been important in control system
implementation for tokamaks under construction and is expected to be
critical for ITER.