Definition and performance analysis of a control system for m = 2, n = 1 MHD modes in JET via computer simulation

The evolution in amplitude and frequency of MHD rotating resistive modes on the q = 2 surface is a limit for the regime of stable operation in tokamaks. It is possible to control the growth and phase of these modes by applying an external magnetic field. This paper presents the performance analysis via computer simulation of a digital real time vector-control system based on reduced state feedback (mode amplitude and frequency). Despite the high noise level superimposed on the whole set of state variables and model parameters as well as the fast dynamic of the mode evolution, the simulation has shown how the mode can be controlled using a discrete control system built by a system of DSPs working in parallel