effect of the disturbances on feedback control system design of plasma horizontal position in ir-t1 tokamak

effect of the disturbances on feedback control system design of plasma horizontal position in ir-t1 tokamak

one of the essential requirements for tokamak operation, and then energy extraction from nuclear fusion reactor, is plasma motion control to avoid any contact of the hot plasma with the wall during the burn phase. for the plasma horizontal position feedback control in ir-t1 tokamak, a linear model is considered. also, the system of vertical field (vf) coil and of the disturbances are modeled. for this purpose, the control variable is specified as the vertical field coil voltage. here, the overall system of ir-t1 tokamak includes vf coil, vacuum vessel, and plasma itself. for control, the pid and lqg control designs are proposed. bode diagrams of these controllers satisfy the stability of the model, especially for the lqg design. in this paper, a 0.2 drop in (β_p + l_i/2) is considered as the disturbance. to study this disturbance effect on control system design, magnetic probes are used to determine the disturbed plasma horizontal displacement in irt1 tokamak. analysis of feedback response of horizontal plasma displacement by the pid and lqg controllers showed that the designed lqg controller satisfies the control requirement and horizontal position recovery time, rigidly, guaranteeing a well-damped closed-loop behavior, for this tokamak. further investigations, simulations, and experiments must be carried out for finding and validating the best controller.