一种恒定开关频率感应电机直接转矩控制

在感应电机I(M)的直接转矩控制(DTC)中,为了提高定子磁链观测的准确性,引入一种结合常规电压模型法和电流模型法优点的混合定子磁链观测模型代替常用的电压模型来观测磁链。针对传统开关表-滞环DTC中开关频率变化大和转矩脉动大的缺点,提出一种具有恒定开关频率控制的DTC策略,使其在定子磁链旋转坐标系内,利用空间电压矢量调制技术合成电压矢量,以实时准确补偿当前定子磁链与转矩误差,从而有效降低了电机运行中的转矩脉动和电流畸变。最后,通过仿真和实验验证了方案的可行性。

A Fixed Switching Frequency DTC for Induction Motor

In direct torque control schemes(DTC) for induction motor,a hybrid stator flux linkage model,which combines both advantages of voltage-current-based model and current-speed-based model,is presented to take the place of the con-ventional voltage-based model used in many applications.Meanwhile,due to some drawbacks like variable switching fre-quency,high torque ripple in conventional switching-table direct torque control,a fixed switching frequency direct torque control scheme is investigated in this paper,which is based on the real-time and accurate compensation of the stator flux link-age vector and torque error using space vector modulation(SVM) in stator flux linkage orientated coordinate.Compared with the conventional DTC,the proposed method gets effective reduction of torque ripple and current distortion.Finally,some simulations and experiments are carried out to confirm the effectiveness of the presented motor.