Fold Angle of Winding Arrangement in Single-Drive Bearingless Motor with Radial Gap

A novel single-drive bearingless motor with a high passive stiffness and wide gap factor is proposed. The singledrive bearingless motor has only one set of three-phase windings. It independently generates both the torque and axial suspension force with only one three-phase inverter and one displacement sensor. Therefore, the single-drive bearingless motors have the advantages of low cost and small size. Only the axial direction z-axis is actively positioned. The other axes, the radial movements x and y and the tilting movements theta(x) and theta(y), are passively stabilized by repulsive passive magnetic bearings. The stator consists of six C-shaped cores and one set of three-phase windings. A novel V-shaped winding structure is proposed to simultaneously generate the torque and active axial force. In this paper, the winding arrangement is presented. In addition, the mathematical calculations are presented in this paper.