Analyze the position sensor and the axial exciting coil EMF of axial and radial air gap hybrid magnet circuit multi-coupling motor

An axial and radial air gap hybrid magnet circuit multi-coupling motor is produced based on hybrid stepping motor. The control of axial and radial air gap hybrid magnet circuit multi-coupling motor is flexible profited from its novel structure with axial coils which can be used as position sensor at the same time that the air gap flux can be adjusted by them. Based on harmonic analysis and experiment on electro-magnetic force in the axial coil, the rotor position detecting principle of axial and radial air gap hybrid magnet circuit multi-coupling motor is developed, which is according to the electro-magnetic force of the axial coils. The analysis and experiment show that the frequency of electro-magnetic force in axial coils is linear relations with the speed of the motor and that in stator coils when 3 phase stator armatures are powered simultaneity. So the sensorless control on the motor is achieved conveniently.