一种改善直接转矩控制低速性能的DSVM改进策略

Improved DSVM Strategy to Modify the Low Speed Performance of Direct Torque Control

传统的交流异步电动机直接转矩控制转矩脉动大,特别是低速区开关频率低且不固定导致转矩脉动尤为明显。在分析离散空间矢量调制(DSVM)方法的基础上,提出了一种DSVM—DTC改进策略,优化低速区的开关表减小低速转矩脉动,提高直接转矩控制的动态性能及系统的稳态性能。仿真结果验证了该策略的有效性和实用性。

Large torque ripples exist in the induction motor based on conventional direct torque control. It is especially obvious that the torque ripples are caused by the low and unstable switching frequency in low speed range. Based on the analysis of DSVM, a modified strategy of DSVM - DTC was proposed to optimize the switching table, which is used to reduce the torque ripples in low speed range and improve the dynamic and steady performance of system. Simulation results prove the validity of this method.