面装式永磁同步电机无差拍直接转矩控制

为解决永磁同步电机传统直接转矩控制脉动大、开关频率不恒定,以及现有永磁同步电机无差拍直接转矩控制计算复杂、电压矢量解不唯一的问题,在电压源逆变器受限的情况下,针对表贴式永磁同步电机提出了一种简化无差拍直接转矩控制,计算出的电压矢量由空间电压矢量脉宽调制方法实现,保证逆变器开关频率恒定,该方法计算简单,无需计算二次方程。考虑到控制系统的延时,对电流进行预测计算,同时为提高定子磁链和电磁转矩的计算精度,设计采用观测器方法对定子磁链观测。仿真和实验结果表明,永磁同步电机的转矩和磁链脉动明显减小,动态性能好。

Deadbeat direct torque control for surface permanent magnet synchronous motor

In order to solve large torque ripple and not fixed switching frequency which are existed in direct torque control (DTC) for permanent magnet synchronous motor,and the drawbacks of the currently deadbeat direct torque control (DB-DTC),such as large calculated amount,not only solution,a simplified deadbeat direct torque control was proposed for surface permanent magnet synchronous motor (SPMSM).To ensure that the inverter switching frequency is constant,the calculated voltage vector was implemented by space vector pulse width modulation.The method is simple without calculating the quadratic equation.Considering the fact that the delay of the control system and the stator flux linkage is not measurable,an observer was developed to estimate stator flux linkage and torque.The accuracy of stator flux and torque was also improved.The simulation and experimental results show that the flux and torque ripples are reduced significantly and have good dynamic performance for surface permanent magnet synchronous motor.