2 MW, 170 GHz coaxial-cavity short-pulse gyrotron — Single stage depressed collector operation

The development of the modular short-pulse pre-prototype as base for the 2 MW, 170 GHz, CW coaxial-cavity gyrotron for ITER upgrade and beyond is in progress at Karlsruhe Institute of Technology (KIT). The current modular pre-prototype configuration allows the generation of >2 MW RF output power in short-pulses with a reasonable electronic efficiency of approximately 30 % without depressed collector operation. Recently, experiments with a single-stage depressed collector (SDC) have been performed. In depressed operation the overall efficiency of the gyrotron has been increased to ~48 %. Achieved results will be presented and discussed in this paper.