THE EFFECT OF TOOTH SHAPE ON RADIAL FORCES IN STEP MOTORS

The effect of tooth shape on radial forces inside the air-pp acting on the stator for a typical step motor tooth profile have been investiga ted by 3D finite element method. It has been found that the radial for ce acting on the stator varies from high to low value due to rotor mov ement. The magnitude of the variation depends on the tooth shape and t he stator and rotor tooth to valley ratio and level of saturation. The result have shown that rectangular tooth shape with Stator tooth to v alley ratio of 1:1 and rotor tooth to valley ratio of 1:3 is the best for reducing radial force variation for the cases studied.