Patent ID: 8040010

Claim:
A permanent magnet motor comprising: a stator, and a rotor disposed oppositely to the stator with a gap interposed; said stator comprising a stator core, and a distributed stator winding mounted to the stator core; said stator core comprising a ring-shaped yoke core, and a plurality of teeth cores protruding radially from the yoke core; said rotor comprising a rotor core, and a plurality of permanent magnets embedded inside the rotor core; said rotor core comprising a salient pole through which magnetic flux passes and an auxiliary salient pole through which magnetic flux passes at both outsides of the salient pole from the rotor core to the stator core in order to generate reluctance torque; a pair of non-magnetic portions being created inside said rotor core and on both sides of the circumferential width of said permanent magnet for one salient pole; a ratio of the number of said salient poles of said permanent magnet in the rotor core to the number of said teeth cores with distributed stator windings is 1:3; a groove of size smaller than width between the two magnets constituting the two adjacent salient poles, is provided on near center between the two adjacent salient poles, and extends in the axial direction of the rotor on the outer circumferential surface of the rotor core, when an angle of said permanent magnet is considered as θ pm and an angle of said one salient pole is considered as θ r , said permanent magnet's pole arc rate θ pm /θ r is 0.65≦θ pm /θ r ≦0.85; and when an angle of said groove or hole is considered as θ q and an angle of said one salient pole is considered as θ r , said permanent magnet's pole arc degree θ q /θ r is 0.04≦θ q /θ r ≦0.05.