随机脉冲位置PWM及其在矩阵变换器中的实现

矩阵变换器是一种开关序列呈矩阵型的交交变换器，具有一系列的优点。以矩阵变换器为研究对象，提出了一种基于传统空间电压矢量PWM的随机脉冲位置PWM控制策略，该策略通过随机改变每个开关周期中零矢量的位置，实现了2种低开关损耗PWM模式之间的随机转换，使矩阵变换器输出电压的谐波成分均匀地分布在较宽的频带范围内，同时介绍了在低开关损耗模式下的一种快速SVPWM算法。利用Matlab编制s函数模块，结合Simulink的仿真工具箱的现有模块组成矩阵变换器的仿真模型，分别在原始空间电压矢量PWM和随机脉冲位置PWM两种控制策略下进行了仿真对比，得到良好的波形和数据，从而验证了随机脉冲位置PWM的可行性和正确性。

Randomized Pulse Position PWM and Its Realization on Matrix Converter

The matrix converter is a new cycle converter with matrix switch sequences, which has a series of advantages. A novel randomized pulse position PWM based on traditional voltage space vectors is proposed, which is worked on the model of matrix converter. In the strategy, the positions of the zero voltage vectors are randomly changed, and then two PWM modes with low switching losses are selected randomly, which make harmonic that comes from matrix converter distribute in a wider frequency range evenly. This paper illustrates a fast algorithm of SVPWM in the less switching loss mode. S-function models are programmed by means of MATLB, which are combined with the models of power system block in SIMULINK to set up the simulation model. And it produces the better waveform and data by the simulation using the two strategies separately. The simulation results verify the feasibility and the practicability of the novel randomized pulse position PWM.