摘要 |
A polyphase cylindrical electrical machine including a non-salient stator, a rotor and an air-gap therebetween, together with a winding energisable to apply alternating current to exert two magnetic fields to rotate about the machine axis to produce a non-rotating force in a selected direction radially of the machine axis, the fields rotating in the same direction and having pole numbers differing by two, the fields being exerted by said current at one frequency to act on the machine rotor with said non-rotating force. |