基于参考磁链电压空间矢量调制策略的永磁同步电机直接转矩控制研究

Study of Permanent Magnet Synchronous Motor Direct Torque Control Based on the Strategy of Reference Stator Flux Linkage and Voltage Space Vector Modulation

设计了基于参考磁链电压空间矢量调制策略的永磁同步电动机直接转矩控制,用PI调节器取代了常规直接转矩控制系统中的开关表和滞环控制器,在每一控制周期计算出参考磁链和估计磁链的偏差,选择相邻非零矢量和零矢量并精确计算出其作用时间。仿真结果表明,与常规永磁同步电机直接转矩控制相比,基于参考磁链电压空间矢量调制策略永磁同步电机直接转矩控制转矩脉动显著减小;转矩和转速动态响应更快;具有更好的动、静态性能。

A novel direct torque control based on the space vector modulation strategy for permanent magnet synchronous motor is proposed. Instead of switching table and hysteresis controller in conventional direct torque control, PI controller is used in the strategy. During each sampling period the error between the reference stator flux linkage and the estimated stator flux linkage is calculated. The two nonzero neighboring voltage vectors are selected and the operating time is calculated accurately. The simulation results show that the torque ripple is dramatically reduced and the transient and static function of the system is improved greatly.