Z源变流器电路结构与拓扑设计I--传统Z源变流器

Circuit Structure and Topological Design of Z-source Converter I-Traditional Z-source converter

本文从传统Z源变流器电路结构出发，得到了更能体现Z源变流器特征的电路结构，并从中提取出 Z 源基本电路单元，分析了它的基本工作原理，推导了基于该电路结构的 Z源变流器电路拓扑设计方法。根据工作区间的不同，传统 Z 源变流器存在两种不同的电路拓扑。分析表明，电压型拓扑中Z源电容电压高于输入电压，而电流型拓扑中Z源电感电流大于输入电流。因此，传统Z源变流器中Z源网络的元件尺寸较大，导致变流器体积与重量大，实现成本高。

A circuit structure which can present the characteristic of Z-source converter more clearly is given based on the traditional structure. The Z-source unit is distilled from the structure and analyzed detailly. Then the Z-source converter topological design method is derived from the structure. There are two traditional Z-source converter topologies in different operation regions. The analysis reveals that the Z-source capacitor voltage is higher than input voltage in voltage-fed topology while the Z-source inductor current is larger than input current in current-fed topology, therefore the size of Z-source network is large which causes a high volumn, weight and cost.