Improving magnetic plasma control for ITER

Several alternative plasma control schemes using the same plasma current and shape controller (SC) with different plasma vertical stabilisation (VS) controllers are explored, assessing their efficiency in the suppression of plasma shape transients after vertical displacement event (VDE) disturbances and their robustness to changes of the local dynamics. We attempt to decrease the settling time and the overshoot peaks while maintaining robustness to changes of local dynamics, by speeding up the controller response to disturbances. For VS, static output feedback (SOF) and linear-quadratic-Gaussian (LQG) control are considered. Both SOF and LQG are further augmented with an additional intermediate-level control loop that attempts to bring the system back to the origin after a VDE event faster than the SC normally does.