Linear and impulse control systems for plasma unstable vertical position in elongated tokamak

Abstract

The paper presents the results of design and simulation of linear and impulse control systems of a plasma unstable vertical position for three plasma linear DINA-L models of the tokamak T-15. The models were obtained from the plasma-physics DINA code on the plasma current flat top of a T-15 scenario and corresponded to three different locations of a horizon field coil: outside of the toroidal coil, between the toroidal coil and vacuum vessel, inside the vacuum vessel. For design of linear controllers a loop shaping approach was used. The controllers designed were simulated in the feedback systems with three types of power supply models: linear element, pulse-width modulation element, and relay element. The feedback systems were tested by Heaviside step-functions and disturbances of minor disruption type. The assessment of performances and stability margins of the systems designed and simulated was done in accordance with a multi-criterion approach.