Influence of the radial plates on the transient oscillations in the ITER toroidal field (TF) model coil using a finite element approach

The transient electrical behavior of the racetrack-shaped TF model coil for the International Thermonuclear Experimental Reactor (ITER) during an energy dump has been investigated using a 3D finite element model. Detailed modeling of the radial plates inherently takes into account the eddy currents in the steel structures. Hence, unlike recent investigations using ordinary lumped network models, the influence of the radial plates on the damping and attenuation of the transient oscillations could be considered. Transient analyses for rise times from 0.5 ms to 500 ms have been performed. Additional AC analyses yielded the transfer function of the coil. Alternatively, a lumped network model was established. Frequency dependent values of the network elements, i.e. effective resistances, self and mutual inductances, have been determined using 2D FE models in a frequency range up to 500 kHz. Thus, it was possible to implement frequency dependent effects into the network model as well.