基于占空比控制的永磁同步电机新型直接转矩控制策略

永磁同步电机传统直接转矩控制在电机低速运行时存在着转矩脉动大、开关频率不恒定等问题,本文在详细分析影响磁链和转矩脉动大小因素的基础上,提出了一种准确确定占空比大小的永磁同步电机新型直接转矩控制方法.该方法基于精确的数学模型利用转矩误差计算出当前所选有效电压矢量的作用时间在整个采样周期中的占空比,实时地调整有效电压矢量的作用时间.仿真和实验结果表明,基于占空比控制的永磁同步电机直接转矩控制在保持传统直接转矩控制优点的基础上,能够有效减小转矩脉动,改善了传统直接转矩控制系统性能.

A Novel Direct Torque Control Strategy of Permanent Magnet Synchronous Motors Based on Duty Ratio Control

Disadvantages of traditional direct torque control (DTC) systems for permanent magnet synchronous motors (PMSM) are high torque ripples and inconstant switching frequency at low speed. A novel DTC strategy of PMSM combined with exact duty ratio calculation is proposed based on the detailed analysis of effects factors of flux linkage and torque ripples. In this method the duty ratio between the action time of effective voltage vector and the sampling period is calculated according to torque errors based on e...