Self-magnetic field measurements of JT-60SA CS model coil

Obana, Tetsuhiro*; Takahata, Kazuya*; Hamaguchi, Shinji*; Chikaraishi, Hirotaka*; Imagawa, Shinsaku*; Mito, Toshiyuki*; Kizu, Kaname; Murakami, Haruyuki; Natsume, Kyohei; Yoshida, Kiyoshi

The central solenoid (CS) of JT-60SA is composed of 4 modules consisting of a quad-pancake and 6 octa-pancakes. In order to verify the process for the coil manufacturing and the fabrication jigs, the CS model coil was developed. The model coil is composed of one quad-pancake. The cold test of the model coil was conducted at the Nation Institute for Fusion Science (NIFS) test facility. The critical current, joint resistance, and pressure drop of the model coil were measured in the cold test. In addition, self-magnetic field of the model coil was measured using Hall sensors. The magnetic fields were varying slightly while holding coil current of 20 kA. The range of the time constant was from 17 sec to 571 sec, which was much longer than the time constant derived from the measurement using the short straight sample.