Closed-Loop Simulation of Model-Based Current Profile Control with the \hbox{DIII-D} Plasma Control System

Current profile control has proven to be a critical requirement for advanced operating scenarios with improved confinement and possible steady-state operation. Limitations exhibited by non-model-based controllers tested at \hbox{DIII-D} motivated the design of model-based controllers that account for the dynamics of the $q$ profile evolution. A control-oriented model of the current profile evolution in \hbox{DIII-D} was recently developed and used to design both open-loop and closed-loop control schemes. In this work, we report on the design and implementation of these advanced model-based controllers in the \hbox{DIII-D} Plasma Control System (PCS) and on the evaluation of these controllers by connecting the PCS to a simulation of the current profile evolution represented by a magnetic diffusion equation.