Recent advances in Tokamak modelling

In this paper we present some of our most recent Tokamak modelling work. We describe how basic physical principles may be used to derive a simple Tokamak model and then discuss how the number of states in this model may be reduced. A recent and major advance in this work has been the creation of system identified models of a Tokamak in Switzerland. We outline how this was achieved and then compare the identified model with the appropriate physics based model. The agreement is surprisingly good. The work is motivated by the need to apply modern control theory to the next generation of Tokamaks, these machines being potential reactor prototypes. The importance of creating an identified model is twofold: firstly, this type of model is suitable for controller design in its own right, but it may also be used to validate models derived from physics principles.