基于动态开关表的TLDMC-PMSM零共模电压直接转矩控制

Zero Common Mode Voltage Direct Torque Control of TLDMC-PMSM Based on Dynamic Switching Table

针对三电平直接矩阵变换器-永磁同步电机系统采用直接转矩控制(TLDMC-PMSM-DTC)时出现高共模电压的问题,提出基于动态开关表的TLDMC-PMSM零共模电压直接转矩控制方法。TLDMC的部分旋转矢量共模电压为零,该方法利用这部分旋转矢量去构建DTC的开关表,但是旋转矢量的分布随输入电压相位的变化而变化,这会导致控制结构的复杂度变高,因此此控制算法通过高维开关表来实现TLDMC-PMSM的零共模电压。但是由于所用旋转矢量数目少并且选择的矢量误差大,从而导致电机的转速和转矩脉动大,该文在此基础上,引入动态的旋转矢量和零矢量去构建动态开关表来解决脉动大的问题。仿真和实验结果表明,该方法在保证动态响应能力快、电机的转速和转矩脉动小的基础上,实现了TLDMC-PMSM系统的零共模电压和安全稳定运行。

Aiming at the problem of high common-mode voltage when direct torque control(TLDMC-PMSM-DTC)is adopted in permanent magnet synchronous motor system of three-level direct matrix converter,a zero common-mode voltage direct torque control method based on dynamic switch table is proposed.Because the common mode voltage of the rotation vector of TLDMC is zero,this method uses the rotation vector to construct the switch table of DTC,but because the distribution of the rotation vector changes with the phase of the input voltage,which will lead to the complexity of the control structure,this control algorithm provides a high-dimensional switch table to realize the zero common mode voltage of TLDMC-PMSM.However,because the number of rotation vectors used is small and the error of selection vector is large,the speed and torque pulsation of the motor are large,so on this basis,dynamic rotation vectors and zero vectors are introduced to construct a dynamic switch table to solve the problem of large pulsation.The simulation and experimental results show that this method realizes zero common mode voltage and safe and stable operation of TLDMC-PMSM system on the basis of ensuring fast dynamic response and small motor speed and torque ripple.