Design and development for JT-60SA ECRF system

Moriyama, Shinichi; Kobayashi, Takayuki; Yokokura, Kenji; Shimono, Mitsugu; Hasegawa, Koichi; Sawahata, Masayuki; Suzuki, Sadaaki; Terakado, Masayuki; Hiranai, Shinichi; Igarashi, Koichi; Sato, Fumiaki; Suzuki, Takashi; Wada, Kenji; Shinozaki, Shinichi ; Fujii, Tsuneyuki

The electron cycrotron range of frequency (ECRF) system (3 MW 5 s at 110 GHz with 4 gyrotrons) will be upgraded to the system having 9 gyrotrons (7 MW 100 s at 110 GHz and 140 GHz) for JT-60SA (super advanced). For the reference antenna design having rotary mirrors, an effective and reliable method of mirror cooling without water is under consideration. As an alternative antenna design, a new concept with a mirror driven in the linear motion which eliminates the flexible tube for coolant supply is under development. The design study featuring beam profile calculation showed feasibility of the antenna in the 0.48 m 0.48 m port. On the gyrotron development, 1.5 MW, 1s has been achieved using SiN insulator instead of AlO. Improvement of the mode converter is in progress and the test aiming at 1 MW, 100 s oscillation will be started in March.