Progress in ECRF system design and development for JT-60SA

Kobayashi, Takayuki; Sawahata, Masayuki; Terakado, Masayuki; Hiranai, Shinichi; Wada, Kenji; Hinata, Jun; Sato, Fumiaki; Yokokura, Kenji; Hoshino, Katsumichi; Isayama, Akihiko; Oda, Yasuhisa; Ikeda, Ryosuke; Takahashi, Koji; Sakamoto, Keishi; Moriyama, Shinichi

Design and developments of electron cyclotron range of frequency (ECRF) system are in progress. An oscillation of 1 MW for 1 s at 82 GHz has been demonstrated as the third frequency of the JT-60SA gyrotron, by which oscillations of 1 MW for 100 s at both 110 and 138 GHz were demonstrated. Moreover, experiments toward higher power (more than 1 MW) have been carried out. Oscillations of 1.5 MW for 5 s and 1.8 MW for 1 s at 110 GHz and 1.3 MW for 1 s at 138 GHz have been demonstrated, so far. Operation conditions will be optimized toward higher power and longer pulse length in future. In addition, the progress in the design and developments of ECRF power supply, launcher and transmission line are reported in the conference.