基于虚坐标系的三电平逆变器SVPWH算法的研究

对于中点箝位三电平逆变器，传统的空间矢量脉宽调制方法需要进行大量的三角函数运算及扇区判定，增大了控制器的计算工作量。为解决这一问题，该文研究一种基于虚坐标系的空间矢量脉宽调制方法。该方法主要包括两个部分：一是根据参考矢量计算合成基本矢量的作用时间：二是根据控制策略对零序分量进行控制选择合适的开关状态。通过对零序分量的选择实现了对中点电位平衡的控制，最后matIab／SimuIink仿真验证给出了实验结果，证明了控制方法的正确性。

Study on SVPWM Algorithm Based on Imaginary Coordinate Transformation for Three-level Inverter

The shortcomings of traditional space vector pulse width modulation （SVPWM） method for the three-level inverter are： needing to estimate the sectors and calculating a lot of trigonometric functions, and it results in the increase of the calculating quantity of micro-processor. To solve these problems, a new method for SVPWM based on Imaginary coordinate transformation is presented in this paper. The algorithm mainly includes two parts： one is the determination of the fundamental components in output according to reference vector, the other is the selection of redundant switch states to achieve a certain zero sequence component control objective. Through choosing different the zero sequence components to balance the neutral-point voltage. Finally, the validity and correctness of proposed SVPWM method is confirmed by maUab/Simulink experiment results.