Long pulse and high power repetitive operation of the 170 GHz ITER gyrotron

ITER用170GHzジャイロトロンの長パルス高パワー繰り返し運転

梶原 健; 春日井 敦; 小田 靖久; 高橋 幸司; 小林 則幸*; 坂本 慶司

Kajiwara, Ken; Kasugai, Atsushi; Oda, Yasuhisa; Takahashi, Koji; Kobayashi, Noriyuki*; Sakamoto, Keishi

First repetitive operation of a 170 GHz long pulse gyrotron with quasi-CW (400 sec pulse width) and high power is presented. Five hours of repetitive operation with 30 min intervals was successfully achieved without any major problem. During the 5 hours of operation, 800 kW output power is maintained, the oscillation efficiency is 35% and the total efficiency including the depressed collector is 56%. The pressure inside the gyrotron returns to the original level after 20 min. The results show the clear prospect for the application of 170 GHz gyrotrons to heating and current drive experiments on ITER.