A coil assembly for sensorless rotor angular position control of a single phase permanent magnet motor. The coil assembly is positioned axially adjacent one end of the motor's rotor core in magnetic coupling relationship with the rotor and substantially independent of the magnetic coupling relationship...http://www.google.ca/patents/US6104113?utm_source=gb-gplus-sharePatent US6104113 - Coil assembly for sensorless rotor angular position control of single phase permanent magnet motor
