Design and Implementation of a Novel Interior Permanent Magnet Bearingless Slice Motor

• Published in: IEEE transactions on industry applications 2021-11, Vol.57 (6), p.6774-6782
• Main Authors: Weinreb, Benjamin S., Noh, Minkyun, Fyler, Donald C., Trumper, David L.
• Format: Article
• Language: English
• Subjects: Air gaps; Algorithms; Bearingless motor; Decoupling; Design; Dipoles; Electrical steels; Force; interior permanent magnet; Levitation; magnetic levitation; Magnetism; Permanent magnet motors; Permanent magnets; Prototypes; Reluctance motors; Rotation; Rotors; Stator windings; Topology; Torque; Winding; Windings
• ISSN: 0093-9994; 1939-9367
• DOI: 10.1109/TIA.2021.3080663

In this article, we present a bearingless motor with a novel segmented dipole interior permanent magnet (IPM) slice rotor. The segmented dipole IPM rotor contains a unique pattern of interior permanent magnets arranged to generate a dipole air gap flux pattern. The magnets are encapsulated within an electrical steel rotor structure. The stator contains a three-phase, four-pole winding for suspension and a three-phase, two-pole winding for rotation. We present analyses of several candidate rotor designs. The analyses indicate that the segmented dipole IPM rotor achieves a reduced tradeoff between force and torque capacity and relatively symmetric force dynamics as compared to prior art designs and alternate topologies. Symmetric and decoupled force dynamics allow a simple force decoupling algorithm to be used. We designed, constructed, and tested a prototype system. We experimentally demonstrate that the prototype system can achieve stable levitation and open-loop rotation.