不同驱动方式下的无刷直流电机性能比较

摘要

针对反电势为梯形波与正弦波的两种无刷直流电机，分析了电机分别在正弦波与六脉冲方波驱动模式下的机械特性、电流波形、换相转矩脉动。推导了反电势为正弦波的无刷直流电动机在方波驱动模式下的机械特性表达式。通过对这两种电机电流波形的对比分析，给出了这两种不同反电势波形的无刷直流电动机在高速和低速时两者电流波形、换相转矩脉动差异的原因。建立了两种电机的仿真模型，仿真结果进一步验证了分析的正确性。%Aimed at two different back EMF (electromotive force) of BLDCM in trapezoidal wave and sine wave forms,the mechanical characteristics,current waveform and commutation torque ripple in sine wave and six pulse square wave driving modes are analyzed respectively.The mechan-ical characteristic expression is derived in square wave driv-ing mode when the back EMF of BLDCM is sine wave. Through comparison,the reasons that caused differences in current waveform and commutation torque ripple are detec-ted.Finally,two simulation models are set up,and the the simulation results demonstrate the validity of the analysis.