19th IAEA Fusion Energy Conference

Development of Gyrotron and JT-60U EC Heating System for Fusion Reactor

K. SAKAMOTO¹⁾, A. KASUGAI¹⁾, YO. IKEDA¹⁾, K. HAYASHI¹⁾, K. TAKAHASHI¹⁾, K. KAJIWARA¹⁾, S. MORIYAMA¹⁾, M. SEKI¹⁾, T. KARIYA²⁾, Y. MITSUNAKA²⁾, M. TSUNEOKA¹⁾, T. FUJII¹⁾ AND T. IMAI¹⁾
1) Naka Fusion Research Establishment, JAERI, Naka-machi, Ibaraki-ken 311-01 Japan
2) Display Devices & Components Company, Toshiba Co., Ootawara-shi, Tochigi, 324-8550 Japan

Abstract.
Abstract. The progress of ECH technology, for ITER and JT-60U tokamak, are presented. In the development of gyrotron, 0.9MW/9.2sec, 0.5MW/30sec, 0.3MW/60sec, etc. have been demonstrated at 170GHz. At 110GHz, 1.3MW/1.2sec, 1.2MW/4.1sec, 1MW/5sec were obtained. It is found that the reduction of the stray radiation and the enhancement of cooling capability are keys for CW operation. Four 110GHz gyrotrons are under operation in the ECH system of JT-60U. The power up to approximately 3MW/2.7sec was injected into the plasma through the poloidally movable mirrors, and contributed to the electron heating up to 26keV(n_e ~0.5x10¹³ cm^-3), and the suppression of the neo-classical tearing mode.