RF behavior of a 200-kW CW gyrotron

Abstract

The RF behavior of a 42-GHz 200-kW continuous-wave (CW) gyrotron for plasma heating in a small experimental tokamak is presented in this paper. The operating mode, as a matter of technical convenience, is the TE0,3 mode, as is required by the end user. Design constraints are carefully investigated, and starting currents are computed. Cold-cavity and self-consistent calculations are carried out; power and efficiencies are computed for a typical set of beam parameters. In addition, a triode-type magnetron injection gun (MIG) has been designed, and the realistic beam parameters obtained from these MIG calculations are used in time-dependent self-consistent calculations which are carried out before and after space-charge neutralization. These studies on RF behavior suggest that it is feasible to realize CW powers in excess of 200 kW at 42 GHz with TE0,3 as the operating cavity mode. © 2008 IEEE.