An AC self-bearing rotating machine with a single set of windings

A self-bearing motor is an integrated device that possesses magnetic bearing capability in addition to the normal torque-producing function. Conventional self-bearing motors have a poor specific power rating and require a high number of power electronic switches. These disadvantages arise from the manner in which the windings are connected. This paper outlines an approach to the realisation of self-bearing motors using a single set of windings with advantages such as: relatively low RMS power loss for a given performance; requiring only one standard power supply for torque production and additional supplies of low current and voltage ratings for the production of lateral force; and preserving the flexibility for extensions to other polyphase machines. Coupled field finite elements simulations are performed to verify this new connection scheme.