Abstract. Effectiveness of the feedback system in stabilizing the resistive wall mode (RWM) has been formulated in terms of the normal modes of the combined dynamical system including the plasma and resistive wall. It has been numerically implemented for tokamaks in general geometry. Application to the realistic DIII–D geometry indicates that upper and lower side band feedback coils can increase the effectiveness of feedback by a factor of 30 (measured in units of the growth rate of the RWM) without resorting to rotational stabilization. For plasma with rotation, different models representing the interaction of the plasma with the RWM are utilized to simulate the time dependent development of the plasma rotation profile and the response of the plasma with respect to externally imposed perturbations. Results from these simulations are compared with those from experiments to evaluate the combined effect of rotation and feedback. *Work supported by U.S. DOE under Grants DE-FG03-95ER54309 and DE-FG02-89ER53297.
IAEA 2003