摘要：永磁无刷电机具有结构简单、效率高、转矩大等优点，然而转矩脉动特别是换相转矩脉动问题，制约了其在高性能设备上的应用。针对无刷电机换相转矩脉动问题，从电机数学模型出发，分析了换相转矩脉动产生机理，提出一种改进型12步换相算法，通过柔性换相过程来抑制无刷电机换相转矩脉动。经验证，该控制策略可以有效增加转动力矩、降低转矩脉动，且算法简捷、复杂度低，便于工程技术实现。

关键词：无刷电机；换相转矩脉动；换相算法
Abstract: Permanent magnet brushless motor  has advantage of simple structure, high efficiency, big torque etc. However, its  torque ripple especially commutation torque ripple restricts its application in high-performance devices. For brushless motor commutation torque ripple, from the mathematical model of the motor, analyzed the mechanism of commutation torque ripple, proposed a modified 12-step commutation algorithm, suppressed the brushless motor commutation torque ripple through a flexible commutation. It was proven, the control strategy can increase the rotational torque, reduce torque ripple effectively. And the algorithm is simple, complexity is low, it is easy to achieve in engineering applications.

Key words: brushless motor; commutation torque ripple; commutation algorithm