PWM调制方式对六相无刷直流电动机转矩脉动的影响分析

建立了六相无刷直流电动机(BLDC)的相绕组数学模型,在此基础上分析了该电机在 PWM 调制方式下的非换相期间关断相电流的产生过程.分析结果表明,在采用PWM_ON_PWM调制方式时,可以消除多相 BLDC 的非换相期间关断相电流,因此可以降低转矩脉动.此外,还分析了该电机在换相期间的转矩脉动情况,得到了由换相引起的转矩脉动解析表达式,并给出了消除转矩脉动应该满足的 PWM 占空比控制条件.

Analysis of influence of PWM method on toque pulsation of six-phase BLDC

Based on the phase windings mathematical models of six-phase BLDC established in this paper,an analysis was given to the generation of pulsating current caused by shutoff phase on the PWM_ON_PWM modulation.The result shows that when PWM_ON_PWM is adopted,the current caused by shutoff phase can be eliminated,and the torque pulsation can be reduced.The analysis of the torque pulsation during the phase conversion has contributed to obtaining the expression of torque pulsation,and presenting the PWM duty ratio condition to eliminate the torque modulation.