Experimental magnetic field mapping of a polycrystalline superconducting YBCO disc for an axial flux motor

Abstract

The method of creating large and complex-shaped melt-textured YBCO bulks based in artificial welding seeds opens the door to the study of applications with polycrystalline superconductor samples. In order to evaluate the superconducting quality of the bulks, Hall probe mapping can be applied in order to measure trapped flux field profiles after magnetisation. This paper describes the magnetic field mapping of an axial flux motor with a polycrystalline high temperature superconductor (YBCO) disc rotor at liquid nitrogen temperature (77 K). An axial flux hall probe is used and magnetic field profiles have been obtained for different polar configurations of a three-phase stator winding which will be operated at 50Hz. After the magnetization of the HTS disc trapped flux is measured, and its magnitude depends on the polar configuration and magnitude of the applied field.