Investigation on Stator Teeth Arrangement for Minimizing Cogging Torque and Linkage Flux Distortion in Hybrid Stepping Motors

The objective of this paper is to find out arranngements of stator teeth for minimizing the cogging torque and the linkage flux distortion in hybrid stepping motors. First, I clarify the influence of the teeth arrangement on the cogging torque on the basis of the equivalent magnetic circuit of the hybrid stepping motors and propose a new method for reducing the cogging torque. Then the same method is applied to reduce the distortion of coil linkage flux. Last, I verify the result of the above method on FEM simulation of the hybrid steppinng motors using two-dimensional model.The crucial points of the result are shown as follows: (1) Cogging torque is able to be reduced by balancing permeance vectors of the teeth divided to 2 or 3 sets on the 4th harmonic plane. (2) The distortion of coil linkage flux is also able to be improved by using the similar method on the 3rd harmonic plane.