Topology Comparison and Design of a Slotted Bearingless High-Speed Permanent Magnetic Synchronous Machine

The design and implementation of a bearingless high-speed motor are presented. Several different rotor and stator topologies are discussed and simulated to determine their suitability for high-speed operation. Finally, the most promising concept is implemented as a prototype. To the author's best knowledge for the first time a bearingless high-speed slice motor with slotted stator is manufactured. The slotted stator features the advantage of reduced magnetic air gap compared to motors with toroidal air-gap windings and slotless stator. The smaller air gap leads to increased air-gap bias flux and increased stiffness values as well as higher force and torque constants. Additionally a damper winding is included to suppress tilt motions.