摘  要：为了获得计时电阻和电感的无刷直流电动机的平均电磁转矩的解析表达式，通过对反电势梯形波平顶120°的三相无刷直流电动机换相过程进行分析，得到考虑绕组电磁时间常数的平均电流和平均电磁转矩解析解，并以两个典型样机实测数据与计算结果对比验证。给出的计算公式可用于工程计算和分析研究。
关键词：无刷直流电动机；换相过程；电磁转矩

Abstract: In this paper commutation process of three-phase trapezoidal-wave back-EMF brushless DC motor was analyzed,analytical solutions of average current and average electromagnetic torque was given,and calculate results in two typical prototype was compared and verified with experiment data.
Key Words: Brushless DC motor；Commutation process；Electromagnetic torque