用空间电压矢量调制异步电动机的直接转矩控制

Direct Torque Control Strategy for Asynchronous Motor Based on Space Vector Modulation

为了减小基本直接转矩控制(Basic-DTC)的转矩和磁链脉动,采用空间电压矢量调制(SVM)与直接转矩控制相结合(SVM-DTC)的方法。从直接转矩控制的基本原理出发,引入SVM方法,详细给出了一种改进型基于磁链矢量偏差法的异步电动机SVM-DTC的分析与实现过程,同时给出了修正的应用于SVM-DTC的磁链观测方法。仿真研究表明,与Basic-DTC方法相比,该方法除了能使转矩和磁链脉动大为减小外,还具有与传统直接转矩控制一样好的动态性能。最后,给出了SVM-DTC与Basic-DTC的实验对比结果,证明了该方法的有效性。

A method is used to decrease the torque and flux ripple in Basic-DTC by combining the space vector pulse wide modulation （SVM） with the DTC strategy. This paper introduces the method of SVM into the DTC from its fundamental principle. SVM DTC is analyzed and realized based on the method of the flux vector error. The modified flux evaluation method is used to improve the low-speed performance of SVM-DTC. Compared with the Basic-DTC, the simulation shows the flux and torque ripples of SVM-DTC are greatly reduced, and switching frequency is fixed. Meanwhile, the good dynamic performance of the DTC strategy is retained. Finally, the experimental results between the Basic-DTC and the SVM-DTC are compared.