Simultaneous Electron Temperature and Safety Factor Profile Control in DIII-D
S. Morosohk, Z. Wang, A. Pajares, S.-T. Paruchuri, E. Schuster
Division of Plasma Physics (DPP) Annual Meeting of the American Physical Society (APS)
Pittsburgh, PA, USA (Remote), November 8-12, 2021
A robust control scheme has been developed to simultaneously control
the electron temperature (Te) and safety factor (q) profiles on DIII-D.
Control of both kinetic and magnetic profiles is crucial to improve
plasma performance and maintain magneto-hydrodynamic stability in
tokamak plasmas. Because of this, techniques to simultaneously control
multiple profiles need to be developed. The dynamics of these profile
can be described by coupled nonlinear parabolic partial differential
equations. The plasma resistivity is modeled as an uncertainty, and r
obust control techniques are used to design a controller that is capable
of tracking prescribed profiles for an expected range of uncertainty.
The controller is then tested in closed-loop simulations by using the
Control Oriented Transport SIMulator (COTSIM). Preliminary predictive
simulation results show that this controller is indeed capable of
regulating both the electron temperature and the safety factor profiles
with acceptable dynamic performance and robustness.
*Supported by the US DOE (DE-SC0010661, DE-FC02-04ER54698) and by the NSF GRFP (1842163).