Patent ID: 6239525
Filing Date: 2001-05-29
Classification: H02K,Y02T

Abstract:
A permanent magnet electric machine comprising:a stator provided with windings thereon; anda rotor disposed with an air gap between the stator and the rotor, and having a plurality of permanent magnets fixed along a circumference thereof, with spacing between adjacent magnets; whereina circumferential extent of surfaces of the permanent magnets facing the stator is selected so that an induced voltage in the machine has a waveform which approximates a sinusoidal waveform; andan angle .theta., whose sides are radii of the rotor passing through opposite circumferential ends of a surface of each permanent magnet which is nearer to the stators, is smaller than an angle .psi., whose sides are radii of the rotor passing through opposite circumferential ends of a surface of each permanent magnet which is farther from the stator.