Subscale HTS Fusion Conductor Fabrication and Testing in High Magnetic Background Field

In actual or future fusion machines like ITER, JT-60SA, W7-X or the present EU-DEMO design, low temperature superconductor (LTS) cables are used or planned to be used in the magnet system to create the strong magnetic field necessary for plasma confinement. High temperature superconductors (HTS) offer the potential to increase the magnetic field strength in fusion magnet systems even further, allowing to build more compact fusion machines or to realize higher flux swings in central solenoids. In this work, two HTS conductors were fabricated and characterized by high current testing at 77 K in self-field conditions and at 4.2 K with an external magnetic field up to 12 T. Both samples offer the same amount of superconducting HTS tapes but differ in the assembly process and termination type. These tests were intended to validate the current KIT design of a HTS CroCo triplet conductor and to qualify a low degradation cable manufacturing process.