单级可升压逆变电路统一拓扑:电抗源逆变电路

X-Source Inverter: Generic Topology of the Single-stage Boost Inverters

在对Z源逆变器(Z-source inverter,ZSI)和准Z源逆变器(quasi-Z-source inverter,q ZSI)等单级可升压逆变电路进行深入研究的基础上,提出单级可升压逆变电路统一拓扑结构——电抗源变换器。该拓扑利于独特的LC组合形式实现了电压源和电流源电路无法实现的功能。以电抗源逆变器(reactance source inverter,XSI)为例阐述该拓扑结构的构成特征、工作原理、推演途径等共性问题,提出2种推演XSI电路的方法,即DC-DC斩波电路开关管代替推演法(SR-XSI)和DC-DC斩波电路二极管代替推演法(DR-XSI)。并以现有的典型电抗源逆变器ZSI和q ZSI为例,论证由"级联DC-DC斩波电路的两级电路"推演出XSI的可行性。基于DR-XSI推演机理,提出一族单级可升压逆变电路,并以Zeta电抗源逆变电路为例,研究该电路的工作原理和具体工作模式。该类单级逆变器能在较小的直通占空比Dsh时得到较高的升压功能,减少了单级逆变电路直通占空比Dsh和逆变器调制因子M之间此消彼长的制约关系。通过仿真软件Saber验证了Zeta XSI电路的升压功能以及所提各种策略的正确性和可行性。最后在实验室建立了1 k W样机进行验证,实验结果和理论分析及仿真结果吻合。

This paper presented a novel reactance source converter （XSC）, which is a unified topology for single-stage converter with Buck-Boost ability, employs a unique impedance circuit （consists of at least one pair of LC filters） to couple the converter＇s main circuit to the power stage, thus providing unique features that cannot be obtained in the voltage-source inverter （VSI） and current-source inverter （CSI） where a capacitor and an inductor are used, respectively. To describe the constitute forms, derivation strategies and operating principle, this paper focused on an example： an reactance source inverter （XSl） applications. Two derivation strategies for XSI were proposed, with which the various XSI was derived from DC-DC converter cascaded VSI, named as SR-XSI method and DR-XSI method. The ZSI and qZSI were proved to be the typical XSI, which are equivalent to Sepic XSI and Cuk XSI, respectively. A family of new XSIs, based on the DR-XSI method, were presented. The principle, analysis of operation, and design guideline were included. The XSIs can achieve high step-up voltage gain with small shoot-through duty cycle Dsh, which decreases the confliction between Dsh and modulation index M. The simulation and experimental results of the 1 kW Zeta XSI prototype were given for hardware verification. The theoretical analysis and simulation agrees well with experimental results.