摘   要：传统的计算铜耗的方法是输入电机的母线电流的平方乘以电枢绕组上的平均电阻。但此方法在计算无刷直流电机实际运行过程中的铜耗时还存在一点欠缺。文章研究了无刷直流电机在PWM斩波调速下的铜耗问题，采用Matlab软件建立模型进行仿真，仿真结果表明，当改变PWM占空比对电机调速时，电机在满负载高速运行状态下用电枢绕组电流计算的铜耗比用母线平均电流值计算的铜耗大。最后通过试验对仿真结果进行验证。
关键词：铜耗；稀土永磁无刷直流电动机；相电流

Abstract: Discussed the copper loss of the rare earth permanent magnetic brushless DC motor(REPM BLDCM)in this paper.The traditional method of calculating the consumption of copper loss of the motor is the product of square of bus current and average resistance of windings.Although this method convenient and practical,but in the brushless DC motor in the actual running there are still a little lacking.The copper loss was analyzed theoretically based on the essential principles of the rare earth permanent magnetic brushless DC motor.A mathematic model is applied to the Matlab simulation of REPM BLDCM.The results of simulation were compared to the experiment data in the paper.It showes the correctness of the Matlab simulation analysis.
Key Words:Copper loss;REPM BLDC Motor;Phase current