永磁无刷直流直线电机齿槽力补偿控制研究

永磁无刷直流直线电机的齿槽定位力对其低速性能影响很大,而单纯的设计方法不可能完全消除齿槽力的影响,为此,必须在控制系统中对齿槽力进行补偿。针对包含齿槽力模型的理想电机控制系统进行了理论分析,指出通过引入位置反馈环节可以消除齿槽力的不良影响。利用有限元分析方法计算了电机的推力和齿槽力波形,验证了低速条件下推力波动主要由齿槽力引起,并说明可以通过位置反馈来补偿推力波动。最后,提出将一个齿槽力周期分为多个区间,然后分段进行线性补偿的简易控制方法。该方法无需高精度的定位装置和复杂的控制算法即可实现对电机齿槽力的补偿,实验结果表明,所提方法能够有效抑制电机的推力波动。

Study on Compensation Control of Cogging Force in PMBLDCLM

Cogging force is a main factor that affects the performance of permanent magnetic brushless DC linear motors(PMBLDCLM) at low speed.Since the cogging force cannot be eliminated thoroughly by design method,compensation must be introduced in the control system.Theoretical analysis of an ideal motor control system with cogging force being considered shows that cogging force can be diminished through a position feedback loop.The finite element analysis(FEA) results prove that the thrust fluctuation of the motor at low speed is mainly caused by cogging force and can be compensated for through position feedback control algorithm.A method of dividing a fundamental circle of the cogging force into sections and performing linear compensation at each section is proposed.Since this method does not need any high precision locating equipments and complicated algorithms,it is easy to be implemented.Experiment results show that the motor thrust fluctuation can be diminished effectively with the method proposed.