一种新型的异步电机SVM-DTC方法

A Novel SVM- DTC Method for Asynchronous Motor

为解决传统SVM-DTC控制方法在低速时稳定比较困难的问题,提出一种新型SVM-DTC控制方法。采用闭环控制的磁链估算新方法,克服在开环控制中磁链估算带来的饱和或直流漂移等缺点;在空间矢量调制中用模糊控制器替代传统的PI控制器,使转矩误差最小,保持恒定的开关频率。实验结果表明,在低速时,该方法比传统方法的磁链脉动和转矩脉动分别减少25%和33%,能消除直流漂移等问题,提高系统的控制性能。

A kind of SVM - DTC approach is presented to overcome the shortcoming of conventional SVM - DTC ways, i. e. , stable difficulty in low speed. As for the proposed approach, closed loop control is utilized to estimate stator flux and this can overcome the drawbacks of the stator flux estimation in open loop control, such as flux saturation and de drift. And fuzzy logic controller replaces the conventional PI controller to minimize the torque ripple and remain a constant switching frequency. The simulation results show that the proposed control method can decrease the flux ripple and torque ripple by 25 % and 33 % respectively, and eliminate dc drift in low-speed, and improve the system control performance.