级联型逆变器的新型简化多电平空间矢量调制方法

传统多电平空间矢量调制(space vector modulation，SVM)方法需要大量的矢量选择等复杂运算，级联数目较高时，算法变得异常复杂而难以实现。该文借鉴载波移相调制的思想，提出一种新颖的基于两电平SVM的简化多电平SVM方法。将各级H桥逆变器施加相同幅值和相位的电压矢量，而将各自的电压矢量更新时间相互错开，进而形成相应的多电平输出电压波形。每个采样周期只需依据两电平SVM算法计算一单元的主、辅电压矢量及其作用时间，计算量与级联数目无关，进而显著简化了算法难度，并增强了可扩展性。三单元情况的仿真和实验结果证明了所提出方法的正确性和可行性。

Novel Simple Multilevel Space Vector Modulation Method for Cascade Inverter

The conventional multilevel space vector modulation (SVM) method is more complex because of the calculations for selecting various vectors, which makes the algorithm more difficult to be implemented when the number of cascaded power units is larger. Borrowing ideas from the principle of carried phase shifted sinusoidal pulse width modulation (SPWM) method, a novel and simplified multilevel SVM method was proposed based on the two-level SVM method. The voltage vectors with identical amplitude and phase were applied to the each power units with the refresh times staggered in order, and then the corresponding multilevel output voltage waveforms would be formed. During every sampling period, only the main and auxiliary voltage vectors, and their operating times in one step power unit needed to be calculated. Because the calculation burden is independent of the cascade number, the algorithm is simplified, and the expandability is enhanced. Simulation and experimental results of three-unit inverter prove its validity and feasibility.