Title :
Analysis of resistive wall mode LQG control in NSTX with mode rotation
Author :
Katsuro-Hopkins, Oksana ; Sabbagh, S.A. ; Bialek, J.M.
Author_Institution :
Dept. of Appl. Phys. & Appl. Math., Columbia Univ., New York, NY, USA
Abstract :
Stabilization of the Resistive Wall Mode (RWM) in the NSTX tokamak is important to achieve high-beta plasmas. This paper numerically investigates state-space control algorithms for improved performance of RWM control using the existing six external control coils with off-midplane poloidal magnetic field sensors in NSTX. Experimentally ßN = 5.6 was achieved with the present proportional gain controller. The proposed LQG controller is capable of reaching ßN = 6.7 for slowly rotating plasma modes and the ideal wall limit ßN = 7:06 for plasma modes with higher natural rotation speed.
Keywords :
Tokamak devices; gain control; linear quadratic Gaussian control; magnetic sensors; plasma instability; plasma magnetohydrodynamics; plasma pressure; plasma toroidal confinement; proportional control; state-space methods; NSTX tokamak; National Spherical Torus Experiment; external control coils; high-beta plasmas; mode rotation; off-midplane poloidal magnetic field sensors; plasma modes; proportional gain controller; resistive wall mode LQG control; rotation speed; stabilization; state-space control algorithms; Coils; Magnetic sensors; Plasmas; Proportional control; Tokamaks;
Conference_Titel :
Decision and Control, 2009 held jointly with the 2009 28th Chinese Control Conference. CDC/CCC 2009. Proceedings of the 48th IEEE Conference on
Conference_Location :
Shanghai
Print_ISBN :
978-1-4244-3871-6
Electronic_ISBN :
0191-2216
DOI :
10.1109/CDC.2009.5400543
