中文摘要：

开关器件的工作频率会对无刷直流电动机（BLDCM）的运行产生影响,尤其当六拍中每一拍所含的PWM开关周期数（波头数）较少时。在此通过详细的理论推导对其所造成的影响进行了定性分析和定量计算,指出滞后换相会在开关周期数变少时对电机产生较大的不良影响,并定量给出电机每一拍中含有开关周期的个数与绕组瞬时电流波动幅值之间的对应关系。实验结果验证了结论的正确性。结论为设计高速BLDCM驱动器时选取最优开关频率提供了定量参考。

英文摘要：

The adopted switching period of brushless DC motor（BLDCM） drive can cause commutation delay on the motor performance, especially when there are few pulse width modulation （PWM） switching periods within one step. The influence of the commutation delay phenomenon is analyzed and calculated in detail.The relationship between the number of switching periods in one step and the instantaneous fluctuation magnitude of winding current is deduced. The experiment confirmes the accuracy of the analysis, and the results are useful for quantitatively choosing the opti- mal switching period of a BLDCM drive.