Device and method for detecting rotor speed of a multiple phase motor with bipolar drive

摘要

The present invention provides a method for detecting rotation of a rotor of a multiple phase motor with bipolar drive, excluding a three-phase motor with bipolar drive with star connected coils or motor stator windings, the motor comprising at least a first and a second energisable motor stator winding. The method comprises sequentially and alternately sensing a voltage on the first and the second motor stator winding during a substantially non-energised state thereof. <??>The present invention also provides an apparatus for detecting rotor speed. <IMAGE>