基于矩阵变换器供电的感应电机DTC系统仿真研究

对于矩阵变换器供电的电机系统,空间矢量调制法只能实现简单的开环VVVF控制且对输入电压抗干扰性能差.基于矩阵变换器开关状态的分析,把矩阵变换器视为直流母线电压为输入线电压的电压源逆变器,并通过仿真实验,验证了矩阵变换器供电的感应电机直接转矩控制系统的可行性.通过对矩阵变换器输入线电压为高、中、低3种情况下直接转矩控制转矩脉动的分析,得出了一种有效减小转矩脉动的控制方法.输入电压非正常下的仿真结果表明矩阵变换器供电的感应电机直接转矩控制系统对输入电压具有较强的鲁棒性.

Simulation Study on DTC System of Induction Motor Fed by Matrix Converter

Space vector modulation(SVM) can only implement open-loop VVVF control for motor system fed by matrix converter(MC) and has a very low immunity to the input voltage disturbances.Based on the analysis of switching state of MC,MC can be viewed as voltage source inverter(VSI) whose DC-bus voltage is input line voltage.Simulation results verify the feasibility of direct torque control(DTC) system of induction motor fed by MC.Based on the analysis of DTC torque ripple with high,middle,and low input line voltage of MC,a control method was proposed to reduce torque ripple by controlling input line voltage.Simulation results under abnormal input voltage conditions verify DTC system of induction motor fed by MC has strong robustness for input voltage.