Design, Development, and Experimental Results of a 30 000-R/Min One-Axis Actively Positioned Single-Drive Bearingless Motor

Abstract

A novel structure design and experimental results of a one-axis actively positioned single-drive bearingless motor is proposed. This new single-drive bearingless motor is proposed by adapting the 4-pole 2-layer permanent magnet rotor and a wide air-gap length for high rotational speed operation. It is found that the rotational speed of 30 000 r/min is experimentally possible, although around 16 000 r/min top speeds were reported in the literature in only one-axis active magnetic suspension. In the machine design stage, it is shown that a wide gap length provides an efficiency improvement with a reduced risk of possible radial position touchdown.