无刷直流电机高精度换相控制

针对无刷直流电机(BLDCM)换相期间不导通相续流而产生端电压脉冲的问题,依据反电动势(EMF)过零法原理,分析了端电压脉冲产生的原因及对反电动势过零检测精度的影响,提出了一种利用软件算法避开端电压脉冲从而实现无位置传感器BLDCM高精度换相的控制方法。首先,利用条件语句及程序运行时间差避开端电压脉冲；为了在重载情况下提高所设计程序运行时间差的容错率,提出一种减小换相续流时间的方法；最后,搭建了无传感器BLDCM试验平台对上述方法进行试验验证。试验结果证明了所提方法在不同占空比和负载下的有效性和准确性。

High Precision Commutation Control of Brushless DC Motor

Aiming at the problem of terminal voltage pulse caused by non conducting phase continuum during commutation of brushless DC motor, based on the principle of back electromotive force (EMF) zero crossing, the causes of terminal voltage pulse and its influence on the detection accuracy of back EMF zero crossing were analyzed. A control strategy for high precision commutation of sensorless brushless DC motor by avoiding terminal voltage pulse using software algorithm was proposed. The conditional statement and program run time difference were used to avoid the terminal voltage pulse. At the same time, in order to improve the fault tolerance rate of run time difference of the designed program under heavy load, a strategy to reduce commutation continuum time was proposed. Finally, a sensorless brushless DC motor experimental platform was built to verify the above strategy. The experimental results showed the effectiveness and accuracy of the proposed strategy under different duty cycles and loads.