Suspension Characteristics of Multi-Consequent-Pole Bearingless Motor with Toroidal Windings

Abstract

Multi-consequent-pole bearingless motors can be used in low-speed rotating and swinging stages (or platforms) under specific conditions. A test machine has been designed and built. In this machine, two axes of freedom are actively controlled in the radial x-y directions. The suspension windings are of a novel toroidal type, in which coils are wound around the stator yoke. The windings realize a short axial length because the coil end-windings are compact. In the design process, the leakage fluxes and magnetic saturation are considered using a three-dimensional finite element analysis. Then, a test machine has been constructed and tested. The rotor was successfully suspended, and its suspension characteristics are presented in this paper.