In the Korea Superconducting Tokamak Advanced Research (KSTAR), quench detection system using central difference averaging (CDA) and mutual inductance compensation (MIK) for central solenoid (CS) magnet has been studied. Similar to the cowound voltage taps, it is expected that this method can provide the good capability of rejecting inductive voltage noise. Accordingly, CDA and MIK method could be considered as a promising way. For this method to be an effective way, the inductive voltages should be accurately estimated, and then the measured CDA voltages are compared with the estimated ones. In previous studies, CS and poloidal field (PF) coils were modeled as the ideal solenoids to calculate mutual inductances between them. However, the nonlinearity of inductances due to Incoloy-908 jackets of PF1-PF5 coils that are ferromagnetic materials still needs to be compensated for more accurate estimation of inductive voltages. In this paper, the inductive voltages were estimated by considering the ferromagnetic effect of Incoloy-908 jackets to compensate the error voltages. Based on this study, the effect of Incoloy-908 on accuracy and reliability of CDA and MIK quench detection scheme was analyzed and discussed.
Bibliographical noteFunding Information:
Manuscript received September 19, 2017; accepted January 29, 2018. Date of publication February 5, 2018; date of current version February 23, 2018. This work was supported in part by the Ministry of Science, ICT and Future Planning of Korea and in part by Ministry of Trade, Industry & Energy, Republic of Korea through “Human Resources Program in Energy Technology” of the Korea Institute of Energy Technology Evaluation and Planning (KETEP) under Grant 20164030201100. (Corresponding author: Yong Chu.) G. Baek is with the Electronics and Electrical Engineering Department, Yonsei University, Seoul 03722, South Korea, and also with the National Fusion Research Institute, Daejeon 305-333, South Korea (e-mail: email@example.com).
All Science Journal Classification (ASJC) codes
- Electronic, Optical and Magnetic Materials
- Condensed Matter Physics
- Electrical and Electronic Engineering