Experimental Study on Gyrotron Efficiency Enhancement

Efficiency enhancement is one of the most important issues in modern high power, high frequency gyrotrons. High efficiency gyrotrons will require less prime power, which results in significant cost savings and increase in reliability of the power supply. To meet the International Thermonuclear Experimental Reactor (ITER) specifications, gyrotron efficiency has to be greater than 50 %. Furthermore, higher efficiency will reduce the collector loading and improve the life time of the tube. Depressed collector operation can enhance the gyrotron overall efficiency significantly. The experimental results from the 1.5 MW, 110 GHz gyrotron with a single-stage depressed collector are presented in this paper.