光伏并网用新型开关电感准Z源逆变器的研究

Research on a Novel Switched Inductance Quasi-Z Source Inverter for Photoyoltaic Grid Connection

针对传统开关电感准Z源拓扑升压能力不足,无法适用于新能源领域的问题,提出了一种改进型开关电感准Z源拓扑,在传统拓扑中增加了一个开关器件和一个二极管。采取3次谐波注入控制策略,在相同的低直通占空比下,即可有效提升直流链电压增益;同时拓宽了调制度范围,确保了输出电压质量;拓扑结构的优化降低了元件电压应力,减小了电感电流纹波。通过理论分析,仿真对比与实验验证了新型拓扑的优越性。

In view of the fact that the conventional switched-inductor quasi-Z source topology boosting capability is not applicable to the new energy field,an improved switched-inductor quasi-Z source topology is proposed,and a switching device and a diode are added in the conventional topology.Adopting the third harmonic injection control strategy,the direct current link voltage gain can be effectively improved under the same low through-duty duty cycle.At the same time,the modulation range is widened to ensure the output voltage quality and the topology optimization reduces the component voltage stress and inductor current ripple.Through theoretical analysis,simulation comparison and experiment verify the superiority of the new topology.