@misc{oai:repo.qst.go.jp:00075499,
 author = {Kobayashi, Takayuki and Takahashi, Koji and Hiranai, Shinichi and Sawahata, Masayuki and Terakado, Masayuki and Sato, Fumiaki and Wada, Kenji and Hinata, Jun and Ikeda, Ryosuke and Oda, Yasuhisa and Kajiwara, Ken and Yokokura, Kenji and Moriyama, Shinichi and Kobayashi, Takayuki and Takahashi, Koji and Hiranai, Shinichi and Sawahata, Masayuki and Terakado, Masayuki and Sato, Fumiaki and Wada, Kenji and Hinata, Jun and Ikeda, Ryosuke and Oda, Yasuhisa and Kajiwara, Ken and Yokokura, Kenji and Moriyama, Shinichi},
 month = {Sep},
 note = {In JT-60SA (Super Advanced), nine sets of evacuated corrugated waveguide transmission lines (60 – 80 m) will deliver high-power millimeter waves generated by nine sets of multi-frequency gyrotrons (1MW each) to four sets of the launchers. Total injection power of 7 MW into plasma is expected by taking into account the transmission loss of 20 – 25% (including loss in a matching optics unit). Toward start of the first plasma experiment in 2020, fabrication of waveguide components is in progress. The waveguide components of gate-valve, dc-break, torus diamond window and pre-load have been newly designed and fabricated. In addition, two types of pumpout tees with a different gap width (1 mm and 2 mm) and cooling/absorbing structure have been fabricated.
In order to evaluate high-power transmission capability of these components, the high-power experiment has been carried out by installing 30 m long test transmission line with seven miterbends in the JT-60SA gyrtron room. It is noted that a newly designed pre-load successfully reduced (20 – 50%) the power deposition on the test waveguide components due to the reflected power from the dummy load. This improvement enabled more clear evaluation of the transmission loss of the tested waveguide components as a simulation of the real situation of the transmission line connected to the tokamak. In this presentation, the detailed measurement results of the cooling water temperature and waveguide surface temperatures is reported., US-EU-Japan RF Heating Technology Workshop},
 title = {High-power experiments of waveguide components for long-pulse millimeter wave transmission},
 year = {2018}
}