Affiliations: [a] Associazione EURATOM/ENEA/CREATE, DIEL,
Università di Napoli Federico II, Via Claudio 21, I-80125 Napoli,
Italy | [b] Associazione EURATOM/ENEA/CREATE, DIMET,
Università Mediterranea di Reggio Calabria, Via Graziella,
Località Feo di Vito, I-89060 Reggio Calabria, Italy | [c] EURATOM/ENEA Association C R Frascati 00044 Frascati,
Italy | [d] See the Appendix of M.L. Watkins et al., Fusion Energy
2006 (Proc. 21st Int. Conf. Chengdu, 2006) IAEA, (2006)
Abstract: This paper deals with the problem of the equilibrium reconstruction
in a tokamak. We firstly describe two approaches for the shape reconstruction:
the former based on a nonlinear least square minimization with Finite Element
Method modelling taking into account the Grad Shafranov equilibrium equation;
the latter based on linear multifilament models accounting for the presence of
iron, eddy currents in the passive structures, and plasma. A possible unified
treatment for shape and current profile reconstruction using both internal and
external measurements is then discussed: the nonlinear least square
minimization procedure used for shape identification is modified to account for
internal measurements and profile shape fitting. A linearized approach is
finally analysed making use of Singular Value Decomposition theory. Some
results on the JET tokamak are shown and discussed.
