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Abstract. Taking into consideration the development and integration of electrical machines with lower dimensions and higher performance, this paper presents the design and development of a three-phase axial flux disc motor, with 50 Hz frequency supply. It is made with two conventional semi-stators and a rotor, which can be implemented with a conventional aluminum disc or a high temperature-superconducting disc. The analysis of the motor characteristics is done with a 2D commercial finite elements package, being the modeling performed as a linear motor. The obtained results allow concluding that the superconductor motor provides a higher force than the conventional one. The conventional disc motor presents an asynchronous behavior, like a conventional induction motor, while the superconductor motor presents both synchronous and asynchronous behaviors.

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A disk-shaped, double stator, induction motor with High Temperature Superconducting (HTS) field coils is proposed in this paper. Copper, typically used in windings of classic machines, limits current density allowed in field coils due to Joule effect losses. Also iron, which is used in magnetic circuits, limits the magnetic flux density obtained in the air gap due to saturation. The application of HTS field coils and iron removal effect in fractional power disk shaped or axial flux motors is analyzed by comparison of two different stator topologies. Twelve HTS field coils made of Bi-2223 (Bi 2 Sr 2 Ca 2 Cu 3 O 1 0) first generation tape, wrapped around a racetrack-shaped nylon core, are assembled. A simple topology was chosen, consisting of six filed coils per semi-stator arranged in the same plane with 60 º displacement. This topology is analyzed theoretically, based on a linear induction motor approach and simulated using a commercial finite elements program, based on the same approach. In order to study the effect of magnetic saturation two stators were built. In the first, the field coils are assembled in steel plates. In the second, the same coils are assembled on nylon plates. The rotor is composed of an aluminum disk assembled on a stainless steel shaft. The HTS coils were cooled by liquid nitrogen (77 K). Simulations, experimental and theoretical results are consistent, showing high space harmonic distortion for the chosen topologies. It is shown that for this type of low power motors operating at this temperature, as iron saturation is not achieved, ferromagnetic materials removal is not a good option. Besides, flux leakage is to high, degrading developed torque.