A preliminary conceptual design study for Korean fusion Demo Reactor magnets

As a continuation of initial conceptual design work for a steady-state Korean fusion DEMO Reactor (K-DEMO), a bit more detailed K-DEMO magnet conceptual design is being carried out. The size of the K-DEMO is only slightly bigger than the ITER and the major radius is around 6.8 m. But the peak field of toroidal field (TF) magnets is as high as ~16 T. Due to a stability issue, the TF magnets will be made of two different cable-in-conduit conductors (CICC's) for the high and relatively low field regions. Some engineering issues, including possible inter coil joint schemes, are discussed. Both CICC's for the TF magnets are designed by assuming the use of a currently available high performance Nb 3 Sn wire. Preliminary CICC design parameters are presented together with simulation results using the code GANDALF. A vertical maintenance scheme is being discussed for the K-DEMO and the location of poloidal field (PF) coils are recently set. However, a preliminary work on central solenoid (CS) coil has been carried out. The CS coils are designed to generate ~83 Wb of flux swing. Preliminary design parameters for the CS CICC are also presented.