60°坐标系下新型模块化多电平变流器空间矢量脉宽调制的简化通用算法

A simple generalized algorithm of space-vector PWM for a new type of modular multilevel converter based on 60° coordinate system

对任意电平逆变器在60°坐标系下的空间矢量脉宽调制通用算法进行研究;并在此基础上推导出了多电平与两电平电压矢量之间的作用时间矩阵;为了减小输出电压波形畸变率,降低开关的损耗,对冗余电压矢量的选择方法和最优合成顺序进行了确定,最后,在PSIM中搭建了模块化多电平的仿真模型,并将基于60°坐标系的空间矢量调制算法用程序实现,证明该简化算法的通用性和正确性,仿真实验也证明随着电平数的增加,输出线电压波形越接近正弦波.

A novel generalized algorithm for arbitrary-number-level converters based on 60° coordinate sys- tem has been studied. The action period matrix between multilevel voltage vectors and two-level voltage vectors has been derived based on 60° coordinate system. In order to reduce distortion of output voltage waveform and switching loss, the selection method and synthetic sequence of redundant voltage vectors has been ascertained. Finally, a simulation model based on MMC is set in PSIM; and the modulation algorithm based on 60° coordinate system is carried out in program; the universal property and validity of simple al- gorithm are proved. The simulation results show that the output voltage is close to sinusoidal wave with the addition of level.