基于载波实现的二极管钳位型三电平逆变器虚拟空间矢量脉宽调制方法

Carrier-Based Virtual Space Vector Pulse Width Modulation for Diode Clamped Three-Level Inverter

首先介绍了二极管钳位型三电平逆变器空间矢量脉宽调制(SVPWM)和虚拟空间矢量脉宽调制(VSVPWM)原理,给出VSVPWM在第一扇区各分区的开关序列。建立包含中点电压平衡方程在内的二极管钳位型三电平逆变器的调制模型,分析VSVPWM策略与基于载波脉宽调制(CBPWM)策略的内在联系,得到基于载波调制的VSVPWM方法(CB-VSVPWM)。在保持输出线电压不变的前提下,改变某一相1电平作用时间来调节由于参数及积累误差造成的中点电位的偏移。最后,实验结果验证了理论分析的正确性。

The space vector pulse width modulation（SVPWM）and virtual space vector pulse width modulation（VSVPWM） for the diode clamped three-level inverter are introduced firstly, and the switch sequences of VSVPWM in the section A are provided. Pulse width modulation model for the diode clamped three-level inverter is established, including the neutral point voltage balancing condition. The carrier based VSVPWM（CB-VSVPWM） is obtained by analyzing the relationship between VSVPWM and carrier based pulse width modulation（CBPWM）. Keeping the output line voltage constant, the shift of neutral point voltage, arising from different parameters and cumulative errors, can be adjusted by changing the duration time of first level of a certain phase. The experiments verify the proposed method.