Design of a Plasma Shape and Stability Control System for Advanced Tokamaks**Work supported by the U.S. Department of Energy under prime Contract No. DE-A03-94-SF20282via Ratheon/Ebasco Subcontract No. ITER-GA-4002 and Contract No. W-7405-ENG-48.††Software copyrighted by General Atomics.

Approaches to the design of plasma shape and stability control systems for advanced tokamaks are described with particular reference to ITER. Nonrigid linear plasma response models are derived using both perturbed equilibrium methods and a variational procedure analogous to the ideal MHD Extended Energy Principle. Multivariable design techniques are applied to allow driving of all poloidal field coils to simultaneously provide stability and control all regulated plasma shape and position parameters. A controller for regulation of plasma-wall gaps in ITER is derived using a perturbed equilibrium plasma response model with linear quadratic Gaussian optimal control design.