As a part of a conceptual design study for developing more higher magnetic field hybrid magnet, an outsert low temperature superconducting coils which can generate about 14 T magnetic field is being developed at the High Magnetic Field Laboratory of the Chinese Academy of Sciences. The superconducting outsert with a room temperature bore diameter of 1800 mm is composed of Nb3Sn coils and NbTi...
A conceptual design study of superconducting toroidal field (TF) magnet for a steady-state Korean fusion demonstration reactor (K-DEMO) was done in 2015. Through some minor design modifications of the K-DEMO TF magnet, the maximum toroidal field strength of the K-DEMO is expected to be about 16 T. In order to test a Cable-In-Conduit Conductor (CICC) of the K-DEMO TF magnet, a conductor test...
Abstract: A closed-loop high temperature superconducting (HTS) magnet with thermal switch, wound by REBCO wire, is proposed, which can be magnetized by flux pump and operated in persistent current mode. In this paper, the structure, fabrication and principle of the magnet is explained. Because the magnet has the structure of thermal switch, it can be excited to saturation efficiently....
REBCO with its high-strength substrate is the preferred superconductor for high-field applications and is the choice for the NHMFL’s 40 T all-superconducting magnet. Many electromechanical characterizations of this conductor have been performed in its longitudinal direction which is its primary load path. Little has been reported on structural limits in its transverse, narrow edge, direction...
High Temperature Superconductor (HTS) based magnets are potential candidate for the future fusion reactors and electrical industries due to its compact size and operational economy. A SS laminated BSCCO-2223 HTS tape based and double pancake wound compact solenoid coil with an inter-double pancake joint of bore diameter 50 mm with 24 nos. of turns has been fabricated and tested at LN2...
Canted-Cosine-theta (CCT) magnet is an excellent dipole magnet structure design for developing high-field accelerator magnets, because of its modular construction and the prevention of the Lorentz-force-induced conductor stress accumulations. Although REBCO tapes can maintain a relatively higher engineering current density than other superconducting conductors in the high field environment, it...
AC losses in stacked bundle conductors exposed to external magnetic fields are numerically evaluated by means of a two-dimensional finite element method formulated using a self-magnetic field due to currents induced in an analysis region. The bundle conductor is composed of two pieces of rare-earth-based coated conductors without electrical insulation to improve the thermal stability. In the...
For mechanical reinforcement against the huge Lorentz forces in high magnetic fields, epoxy resins are commonly used to impregnate the high temperature superconducting (HTS) coils. However, performance degradation of the epoxy impregnated HTS coils is inevitable due to different thermal expansion coefficients between the epoxy resin and the HTS tape. The ice impregnation technique of pulsed...
During the NHMFL 32 T magnet project, a program to develop a reliable method for making soldered lap joints between REBCO tape conductors was initiated. Several combinations of solder, flux and process were tried and then tested in liquid nitrogen. A standard process was adopted from the findings of that study. For each unique REBCO conductor piece procured for the 32 T project, a lap solder...
