基于锁相环和双模速度双重控制的永磁无刷直流电机的研究

Study of the permanent magnet brushless DC motors based on phase-locked loop and dual mode speed control

无刷直流电机系统具有转矩电流比高、转速高、动态性能好、可靠性高和易于控制等优点,在中小功率驱动场合应用广泛;但其缺点是转矩脉动大并易造成速度波动,目前普遍采用速度-电流双闭环PI控制。在无刷直流电机用于某些负载变化率大及大惯量的速度控制模式下时,可能因速度不稳带来震动、谐振、噪声等问题。研究讨论了一种基于锁相环和双模的速度控制法,利用锁相环加上速度环的方法,有效改善了传统速度电流PI调节器在无刷直流电机大惯量负载中存在的转速波动问题,在实际应用中具有良好的速度控制精度和稳定性。

Th e brushle ss DC motor has high torque-current ratio,high speed,good dynamic performance,high reliability and easy to control properties,so it has been widely using in medium and small power drive occasions,but it has disadvantages of large torque ripple and easy to cause speed fluctuation. At present,the speed-current double closed loop PI control is widely used. When brushless DC motor used in the speed control mode with large load rate and big inertia,it may cause shock,resonance and noise problems due to unstable speed. The phase-locked loop and dual-mode speed control method is given. By using the phase-locked loop and speed loop,the rotational speed fluctuation problem of the traditional speed-current PI regulator in the brushless DC motor big inertia load is effectively improved. The system has good speed control precision and high stability in practical applications.