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 Nb₃Sn 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.