Nonlinear modelling of the effects of plasma perturbations in tokamaks

Fusion plasmas in tokamak devices are prone to several unexpected perturbations (ELMs, minor disruptions, L-to-H transitions etc.). These events may terminate prematurely the experiment and hence must be suitably counteracted. To this purpose, suitable modelling is needed. This paper addresses this issue, with particular reference to the JT-60SA tokamak device currently under construction in Japan.