Study on electric motors with bulk superconductors in the rotor

We have studied electric motors using YBCO bulk superconductors in the rotor. The superconductor can be used as a screening material, a magnetic hysteresis material, a flux source, or a secondary conductor, and form several types of motors. This paper describes experimental results of torque characteristics obtained with a small electric motor using a superconducting bulk rotor, which was operated in the synchronous and slip modes. Dependence of the torque on the stator three-phase current (gap flux density) and the slip frequency will be analyzed.