COMPREHENSIVE CONTROL OF A TOKAMAK FUSION REACTOR UTILIZING OPTIMAL CONTROL THEORY

THE CONTROL OF TOKAMAK FUSION REACTORS REQUIRES A QUALITATIVELY MORE ADVANCED CONTROL CONCEPT THAN THAT USED ON PRESENT DEVICES. A TOKAMAK CONTROL STRATEGY MUST DEAL WITH STRONGLY COUPLED PARAMETERS IN A MULTI-INPUT/OUTPUT SYSTEM. THE APPROACH USED IN THIS PROJECT UNITES ELECTROMAGNETIC EQUILIBRIUM, PLASMA STABILITY, AND BURN CONTROL WITHIN THE FRAMEWORK OF MODERN OPTIMAL CONTROL THEORY. PREVIOUS WORK HAS PROVIDED A METHODOLOGY FOR PLASMA FEEDBACK CONTROL OF PLASMA CURRENT, POSITION, AND SHAPE IN A REALISTIC REACTOR DESIGN. THIS PROJECT CONCENTRATES ON DEVELOPING A KINETIC CONTROL THAT CAN BE COMBINED WITH THE ELECTROMAGNETIC CONTROL. IT FOCUSES ON DERIVATION OF PLASMA TEMPERATURE, DENSITY, AND CURRENT DENSITY PROFILES FROM THE ORIGINAL TRANSPORT EQUATIONS. THEPROFILES WILL BE CHARACTERIZED BY A MOMENTS EXPANSION IN THE RADIAL COORDINATE. THIS PROFILE CONTROL WILL BE USED FOR KINK AND FLUTE MODE STABILIZATION, AS WELL AS BURN CONTROL. THE BURN CONTROL INCLUDES BOTH THERMAL STABILIZATION OF A BURNING PLASMA, AND OUTPUT POWER MODIFICATION. BECAUSE OF THE STRONG COUPLING BETWEEN THE VARIOUS PLASMA PARAMETERS, KINETIC AND BURN CONTROL CAN AFFECT ELECTROMAGNETIC CONTROL AND VICE VERSA. THE TECHNIQUES DEVELOPED WILL ALLOW KINETIC CONTROL TO BE COMBINED WITH ELECTROMAGNETIC CONTROL, THUS PROVIDING AN OVER-ALL CONTROL STRATEGY.