ABSTRACT
A permanent magnet brushless motor has the magnets mounted on the rotor and the armature winding mounted on the stator. In a DC brush motor the power losses occur mainly in the internal rotor with the armature winding which limits the heat transfer through the air gap to the stator and consequently the armature winding current density. The most direct and popular method of providing the required rotor position information is to use an absolute angular position sensor mounted on the rotor shaft. The armature winding of permanent magnet brushless motor is usually distributed in slots. When cogging torque needs to be eliminated, slotless windings are used. The application of rare-earth permanent magnets to synchronous motors not only eliminates the need for an exciter, but also offers much lower motor volume, limited maintenance, high efficiency over a broad range of loads, very good dynamic performance and reduced noise.
