Feedback suppression of the radiative condensation instability

Abstract

A new scheme of feedback suppression of the radiative condensation instability in the tokamak edge plasma is presented. The physics basis of this scheme is the modulation of the parallel electron thermal flux at the instability frequency via a feedback circuit. The latter consists of a temperature sensor, amplifiers, phase shifters, and a suitable form of insulated segmented poloidal limiter sections used as suppressors. The necessary feedback power is the order of a kilowatt for small tokamaks and a few megawatts for large reactor‐type machines.