单相四开关Z源AC-AC变换器

提出了一种单相四开关Z源AC-AC变换器,它包括电压型与电流型两类。与传统脉宽调制AC-AC变换器相比,它具有如下特点:输出电压范围宽且可升可降,输出电压与输入电压可同相或反相,冲击和谐波电流小,可靠性高。针对AC-AC变换器中固有的开关管换流问题,提出了一种适用于单相四开关Z源AC-AC变换器的换流方案,无需外加缓冲吸收电路即可实现开关管的安全换流。以电压型单相四开关Z源AC-AC变换器为例,对其进行了理论分析、仿真和原理试验研究。实验结果证实了Z源变换器的特性及换流方案的可行性。

Single-Phase Four Switch Z-Source AC-AC Converters

A new family of single-phase four switch Z-source AC-AC converters is proposed,including voltage-fed Z-source AC-AC and current-fed Z-source AC-AC converters.Compared with traditional AC-AC converter circuits,they have unique features: providing a larger range of output AC voltage with buck-boost ability,reversing or maintaining phase angle,and reducing in-rush and harmonic current.A new commutation strategy for single-phase four switch Z-source AC-AC converters is proposed to solve the commutation problem existed in AC-AC converters.The safe commutation can be achieved without adding the snubber circuit. Theoretical analysis,simulation and the experiment are given based on the voltage-fed Z-source AC-AC converter with input and output sharing the ground.Experimental results verify the unique features of Z-source AC-AC converters and the proposed commutation strategy.The switching loss can be reduced and the high reliability can be achieved.