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Saigusa, Mikio*; Oyama, Gaku*; Matsubara, Fumiaki*; Takii, Keita*; Sai, Takuma*; Kobayashi, Takayuki; Moriyama, Shinichi
Fusion Engineering and Design, 96-97, p.577 - 582, 2015/10
Times Cited Count：6 Percentile：48.72(Nuclear Science & Technology)A wideband polarizer has been developed for an ECCD system in JT-60SA. The groove depth of the mirrors installed in miter bends were optimized for two frequencies (110 GHz and 138 GHz) by numerical simulations. All surfaces of Poincare spheres were covered at both of the frequencies in low power test. The thermal stress of polarizer were estimated by the numerical simulations. The twister polarizer has been tested up to 0.24 MW during 3 s at 110 GHz.
Sugiyama, Naoya*; Oyama, Gaku*; Matsubara, Fumiaki*; Saigusa, Mikio*; Isayama, Akihiko; Kobayashi, Takayuki; Moriyama, Shinichi
no journal, ,
The development status of a wide-band polarizer for ECCD system in JT-60SA is reported. The polarizer was designed at the frequency bands of 110, 130 and 140 GHz based on the simulation results with the finite differential time domain (FDTD) method. The properties of polarizer have been measured with low power test at both of the frequency bands of 110 GHz and 138 GHz. In future work, it is necessary to draw the Poincare sphere based on an experimental result, and to optimize the depth of the grooved mirrors. After that, the wide-band polarizer with a cooling system will be designed, fabricated and tested at high power up to 1 MW.
Sugiyama, Naoya*; Oyama, Gaku*; Matsubara, Fumiaki*; Saigusa, Mikio*; Kobayashi, Takayuki; Isayama, Akihiko; Moriyama, Shinichi
no journal, ,
Electron Cyclotron Current Drive (ECCD) is one of the most promising methods of heating and driving current in fusion plasmas. Incident wave into fusion plasmas should be converted from the linear polarization of a gyrotron output mode to the specific elliptical polarization in order to generate suitable plasma wave at high mode purity. The polarizer was designed at the frequency bands of 110,130 and 140 GHz based on the simulation results with the finite differential time domain method. The mock-up polarizer has been tested with low power at the both frequency bands of 110 GHz and 138 GHz. The high power model of wide-band polarizer was designed considering the results of low power test.
Oyama, Gaku*; Sugiyama, Naoya*; Matsubara, Fumiaki*; Saigusa, Mikio*; Kobayashi, Takayuki; Isayama, Akihiko; Moriyama, Shinichi
no journal, ,
no abstracts in English
Sai, Takuma*; Matsubara, Fumiaki*; Takii, Keita*; Oyama, Gaku*; Saigusa, Mikio*; Kobayashi, Takayuki; Moriyama, Shinichi
no journal, ,
no abstracts in English
Sai, Takuma*; Matsubara, Fumiaki*; Ishida, Yoshitaka*; Saigusa, Mikio*; Kobayashi, Takayuki; Moriyama, Shinichi
no journal, ,
A wideband polarizer were developed for an electron cyclotron current driving system in JT-60SA. The wideband polarizer consists of a twister and a circular polarizers. The polarization properties of the twister was confirmed in cold tests. A high power test of the twister was carried out at an input power of 0.25 MW, 3 s at a frequency of 110 GHz. A new polarizer was designed for next high power tests. The circular polarizer of the different groove period was simulated by numerical simulations using a FDTD method.
