Basic Design and Progress of Central Solenoid Model Coil for CFETR

The central solenoid model coil (CSMC) project of China fusion engineering test reactor (CFETR) began in 2014 and the purpose is to develop and verify the manufacture technology of the large-scale superconducting magnet. The Nb 3Sn cable-in-conduit-conductor (CICC) is chosen for CFETR CSMC as the best conductor type because of 12 T field and 1.5 m inner diameter design requirement. The CFETR CSMC consists of two coaxial solenoid coils named Nb3 Sn coil in the high field region and NbTi coil in the low field region to optimize the manufacture cost effectively. The maximum field of the Nb3Sn and NbTi coil can reach to 12 T and 6.1 T, respectively, when the operating current is 47.65 kA. In this paper, first, the basic design aim and operation requirements of CFETR CSMC are summarized. Second, the characteristics of Nb3Sn superconducting strands and CICCs are described in detailed. Subsequently, the basic structure design of CFETR CSMC is presented in the third part. The current sharing temperature and coupling loss measurement of Nb3Sn CICC sample, as the most important stage assessment, are performed in SUTLAN test facility and some meaningful conclusions are.