基于能量单元法的无刷直流电机导通区转矩脉动

Conduction Torque Ripple in BLDCM Based on Energy Unit Method

在对无刷直流电机(BLDCM)非导通相二极管续流进行分析的基础上,利用能量单元法对非换相期间(导通区)电磁转矩脉动进行量化分析,推导出了PWM调制方式下导通区转矩脉动计算的公式。结合混合动力电力驱动的电路结构,采用了在三相逆变桥入端加上双向直流变换器的驱动拓扑结构与相应的控制策略,消除了BLDCM在导通区内非导通相的续流现象,从而抑制了导通区内的电磁转矩脉动。实验结果验证了该方法的有效性,提高了BLDCM在混合动力车中的应用精度。

The torque ripple of brushless DC motor（BLDCM） in conduction region is analysed precisely using energy unit method based on the research of diode freewheeling of the inactive phase.A formula is derived to calculate the torque ripple in conduction region under conventional PWM schemes.Combined with the circuit configurations of hybrid system,this paper proposes a new topology by adding a Bi-directional DC/DC Converter at the front of the inverter.The torque ripple in conduction region is suppressed by eliminating the diode freewheeling phenomenon.Experimental results indicate the effectiveness of the new topology.BLDCM can be used more precisely in hybrid system.