中文摘要：

在分析无刷直流电机两两导通双极性脉宽调制（PWM）方式的基础上,提出一种改进的双极性PWM无刷直流电机（BLDCM）控制方式,该方式采用4个功率管同时进行PWM控制,其中同一桥臂上下两个功率管处于互补导通模式.分析了该PWM方式对无刷直流电机续流过程及电磁转矩的影响,与传统的双极性PWM方式相比,采用该双极性PWM方式可以减小转矩脉动,低速时平稳性好,并且适用于快速启、制动和频繁正反转场合.仿真和实验结果表明该双极性PWM方式能够显著改善无刷直流电机的转矩脉动问题.

英文摘要：

On the basis of the traditional bipolar pulse width modulation （PWM） control method, a novel improved bipolar PWM scheme used in brushless DC motors （BLDCM） is proposed, in which four power transisitors are controlled simultaneously by PWM signals and the on-off states of two power transistors in one phase leg are opposite. In addition, the process of currents flowing and infec- tion of magnetic torque in proposed PWM method are analyzed. Compared with the traditional bipolar PWM method, this scheme can reduce torque ripple, improve the motor perfomance under low speed, and can be applied in the start-up, braking rapidly and running forward or reverse frequently. Simulation results from Matlab and experimental ones from digital signal processors show that the proposed PWM scheme can reduce the torque ripple in BLDCM obviously.