关键词: 齿槽转矩, 直流电机, 有限元, 径向偏心

Abstract: Cogging torque is one of the problems unique to permanent magnet motors. In high-precision application needs to run through the entire process of motor design,manufacturing and control. Based on the electromagnetic field modulation theory,a pole radial eccentricity topology optimization method was proposed, and a two-dimensional finite element electromagnetic field simulation model was constructed with a 6 - pole,9 - slot DC motor as the research object. Comparing the nonlinear mapping relationship between the eccentricity parameters and the cogging torque at different radial eccentricity amounts 0 ~ 3. 5 mm through parametric scanning, the peak value of the cogging torque is significantly reduced to 0. 93 mN·m when the radial eccentricity reaches 3. 2 mm. The finite element simulation results show that the optimized pole structure not only effectively attenuates the air gap permeability harmonics,but also improves the no-load and load performance of the motor. On this basis, the three-dimensional model of the motor was constructed,the test prototype was made and tested,and it was verified by the test that the relative errors between the performance parameters of each phase and the simulation results are controlled within 5 % of the engineering allowable range. This study provides a quantifiable design methodlogy and engineering validation for cogging torque rejection of permanent magnet motors.

Key words: cogging torque,DC motor,finite element,radial eccentricity