Study on kinetic control mechanisms for ITER-like plasmas

The temporal evolution of the operating point of a fusion plasma during the ignition access, during ignited and subignited operation phases, is analyz ed for plasmas like that of the International Thermonuclear Experimental Re actor (ITER) on the basis of a one-half-dimensional set of equations includ ing feedback equations for axiliary heating and fuel supply. It is shown th at simple proportional feedback controls do not work taking into account th e delay times in the control process. Proportional-integral-differential (P ID) and improved types of control are examined for the purpose of controlli ng a fusion plasma against sudden parameter changes. On this basis a study on the simultaneous use of D-T fuel injection and auxiliary heating control methods for an ITER-like plasma is carried out, resulting in an algorithm capable of finding the optimal operation point in the ignited regime or a h igh-e operating point in a subignited case taking into account density and beta limits and stabilizing the reactor performance against changes in conf inement.