Demonstration of 1 MW quasi-CW operation of 170 GHz gyrotron and progress of EC technology for ITER

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

In the last two years, significant progress has been obtained in the development of electron cyclotron heating and current drive (EC H and CD) technology for ITER. On the 170 GHz gyrotron, 1.02 MW power generation was attained for 800 s pulse duration with an efficiency of 55 percent for the first time in the world, which satisfies the ITER criteria of 1 MW, 500s, 50%, respectively. The total output of microwave energy from the gyrotron is 190 GJ without any trouble. A 0.97 MW, quasi-CW power transmission was proved using the ITER relevant waveguide system. The basic design was completed for the equatorial launcher, and a mock-up of key components, such as a movable mirror, were fabricated. These give a clear prospect for the success and accomplishment of the EC H and CD system on the ITER.