${\rm I}_{\rm c}$ and AC Loss of 2G YBCO Tape Measurement for Designing and Fabrication of an HTS Motor

Abstract

This paper presents a new synchronous motor whose stator uses 2 High Temperature Superconducting (HTS) pancake-coils wound from 2G HTS tapes and 4 conventional copper coils, while the rotor contains 75 bulk HTS elements. All superconducting materials are cooled by liquid nitrogen (77 K). The HTS and copper armature includes 3 phase circuit and is mounted in the slots of a nonmagnetic and insulating material. Each phase winding, fabricated in the form of a pancake-coil, is distributed in slots of 60-degree intervals. YBCO melt-textured pucks were incorporated into the rotor and the reluctance was tested. In addition, a unique cooling system using a copper conductor is designed, which is similar to that of a superconducting flywheel. Finally, we present and analyse results on measuring DC critical current and self-field AC loss in HTS tape supplied by American Superconductor. The measurement systems are described. The results on the AC loss measurement of YBCO samples are presented and analyzed within the framework of the critical state model.