Experimental Characterization of a Conventional (Aluminum) and of a Superconducting (YBCO) Axial Flux Disc Motor

Abstract

An equivalent model and electromechanical characteristics for the disk motor was obtained based on the Steinmetz parameters. This paper describes a series of tests conducted on an axial flux motor, equipped with an aluminum rotor disc and an YBCO high temperature superconducting rotor disc, at liquid nitrogen temperature (77 K). The rotating magnetic field was produced by a four-pole, three-phase stator winding, at 50 Hz. At asynchronous permanent regime, Steinmetz-type models are able to describe both motors' behavior. From the performed tests, the parameters of both motors' models were deduced. A variable load was used to obtain both motor's characteristics (conventional and superconducting). Experimental obtained characteristics of both motors are compared with the ones predicted from parameters' calculation. The HTS motor provides high efficiency then the conventional ones.Index Terms-Axial flux disc motor, HTS materials, YBCO.

Experimental Magnetic Field Mapping of a Polycrystalline Superconducting YBCO Disc for an Axial Flux Motor

“…The field in the HTS material depends on its magnetic history, exhibiting several magnetic excursion that defines the operation regimes of the motor: in the synchronous regime, the rotor is synchronous with the stator rotating magnetic field due to trapped flux; however, in the asynchronous regime the rotor's magnetic field slides over it and flux flow is present, leading to losses and, consequently, torque. For the asynchronous regime, the torque is given by (1) [5], and is maximum when the rotor is all magnetized. Since torque proportional to the losses in the HTS material, it is useful that as much HTS material as possible gets penetrated by flux in order to take advantage of the disc size.…”