Compared with traditional voltage-source inverters,the quasi Z-source inverter (qZSI)has higher voltage boosting ability and stability and has been used in the photovoltaic (PV)system,but it needs different modulation strategies to realize its advantages. In order to reduce switching loss of output voltage of the PV system and total harmonic distortion (THD), this paper proposes a kind of new voltage vector pulse-width amplitude modulation strategy which takes no account of zero vector in each section while only insert the shoot-through zero vector into the single phase bridge-arm with switching opera-tion in each section so as to greatly reduce switching frequency of the inverter. Simulation and experiment has verified effec-tiveness of this strategy.%相比于传统的电压源型逆变器,准 Z源逆变器(quasi Z-source inverter,qZSI)具有更高的升压能力和稳定性,目前已应用于光伏并网系统中,但 qZSI需要采用不同的调制策略来实现其优势.为了降低光伏系统输出电压的开关损耗和减少总谐波失真,提出了一种新型空间矢量脉冲宽度幅值调制策略,它不考虑各扇区的零矢量,仅在各扇区具有开关动作的单相桥臂上插入直通零矢量,从而使逆变器的开关频率大为降低.仿真和实验结果验证了该策略的有效性.
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