交-交矩阵变换器电压传输比的仿真研究

针对矩阵变换器电压传输比低的缺陷,提出了一种新颖的调制策略。借助矩阵变换器间接变换法的基本思路,虚拟整流过程中,采用输入电流的空间矢量调制;虚拟逆变过程中,采用输出电压空间矢量过调制模式I,然后,消除中间直流环节,得到交-交矩阵变换器的控制策略。着重对输出电压空间矢量过调制模式I进行了详细的分析,给出了有关具体的控制算法以及电压传输比与调制系数的关系式等,由计算可知,电压传输比可以提高到0.91。最后,运用MATLAB语言进行了建模,通过仿真实验验证了这种新颖控制策略的可行性。

Simulation Research on Voltage Transfer Ratio for AC-AC Matrix Converters

A new kind of modulation strategy was put forward for the lower voltage transfer ratio of matrix converter. By means of the basic thought of indirect converting method for matrix converter, in virtual process of rectifying, the space vector modulation was adopted for input current; while in virtual process of inverting, the space vector over-modulation mode I was used for output voltage. Then the middle DC link was eliminated and the control strategy for AC-AC matrix converter was gotten. A careful analysis was mainly given to the output voltage space vector over-modulation. Further, a concrete control algorithm and the expression between voltage transfer ratio and modulation index were given, etc. The voltage transfer ratio of matrix converter can be raised to 0.91 by mathematical calculation. Finally, the model was set up in MATLAB language. Simulation experiments demonstrate that the new modulation strategy is feasible.