Plasma-circuit interactions in rotating magnetic field current drive

The interactions between the plasma and the radio frequency circuit in rotating magnetic field (RMF) current drive experiments are investigated numerically. A simplified 1D model for slowly varying conditions is used to study the penetration of the RMF into the plasma. The RMF is assumed to be generated using a two-phase two-coil arrangement and the effect of the spatial harmonics of the field is included up to the ninth harmonic. Both the coil inductance and resistance vary as the RMF penetrates into the plasma and thus influence the current in the antenna coils. The simulation results help in understanding the complex interactions between the radio frequency circuit and the plasma discharge and may help in optimizing the performance of RMF current drive experiments. © 2008 IOP Publishing Ltd.