Quench detection of fast plasma events for the JT-60SA central solenoid

Murakami, Haruyuki; Kizu, Kaname; Tsuchiya, Katsuhiko; Kamiya, Koji; Takahashi, Yoshikazu; Yoshida, Kiyoshi

The JT-60 is planned to be modified to a full-superconducting tokamak. The maximum temperature of the magnet during its quench might reach the temperature of higher than several hundreds Kelvin that will damage the magnet itself. The high precision quench detection system, therefore, is important in the protection system. The disk-shaped pickup coils are inserted in the CS module for quench detection. Thus we improved the analysis model to evaluate the applicability of the disk-shaped pickup coils to quench detection system during the fast plasma event, such as disruption, by introducing the passive coil series such as vacuum vessel and stabilizer. The analysis results show that the disk-shaped pickup coil is applicable whenever the standard operation and fast plasma event. Additionally, the pickup coil design method is also modified to reduce the total cost of protection system. In this paper, the improved analysis method, modified design method and those results are described.