Permanent magnet motor

摘要

A permanent magnet motor having a stator (1) and a permanent magnet rotor (4) facing the stator (1) with a gap therebetween. The stator (1) has a plurality of stator magnetic poles (2) extending radially toward a peripheral surface of the rotor (4), s number of small stator teeth (3) formed on a tip end of each of the magnetic poles (2), and exciting windings of m phases wound around the stator magnetic poles (2). The rotor (4) has a cylindrical permanent magnet (5) having pieces of N pole and pieces of S pole arranged alternately in a peripheral direction thereof at equal pitches, wherein a pitch of the small stator teeth (3) is 1 +/- 1/ (2ms) times larger than a pitch of the rotor magnetic pole pairs. The width of the small stator tooth (3) is 37 SIMILAR 47 % of the magnetic pole pitch. A depth of the groove formed between the adjacent small stator teeth (3) is more than 15 times larger than the length of the air gap between the stator (1) and the rotor (4). <IMAGE>