单级可升压逆变电路拓扑形成理论和电抗源逆变电路关键技术研究

Single-Stage Boost Inverter (SSBI) is suitable for power conversion and management of distributed power generation systems due to its advantages such as high efficiency, safety and adjustable voltage.However, the proposal and research regarding existing SSBI are conducted separately and individually, such as the impedance-source inverter (ZSI). Current literatures do not deeply investigate the theory of topology formation of SSBI, thus it results in a lack of theoretical basis. Based on the common features of the SSBI circuit, this study investigates its topological connotation, and proposes a SSBI Unified Topology-Reactive Source Inverter(XSI). Furthermore, the research highlights the inherent relationship and topological commonalities of different SSBI, investigates the unified working principle of SSBI, and proposes two deductive methods for SSBI formation. The result provides theoretical basis and methodological references for formation of different SSBIs, and makes a commendable attempt and useful supplement for circuit topology. There are some common drawbacks of SSBI due to the "shoot-through" state, such as switching loss, resonance, and EMI interference. Thus, the study aims to apply the proposed SSBI topology formation theory and soft switching theory to obtain a high-performance green SSBI circuit. Pre-study results show a significant improvement of soft switching SSBI in terms of system loss and EMI environment; these results provide theoretical basis and move the research towards the definition of new high-efficient green SSBI.

单级可升压逆变电路（SSBI）具有高效、安全和电压任意可调的优点，适合于分布式发电系统的电能转换和管理。现有SSBI的提出和研究都是单独、孤立地进行,如阻抗源逆变器（ZSI）。没有文献对SSBI拓扑形成理论做深入研究，造成SSBI电路的形成缺乏理论依据。本课题拟从SSBI电路共有特性出发，研究其拓扑内涵，提出SSBI的统一拓扑：电抗源逆变电路（XSI）。揭示不同SSBI的内在联系和拓扑共性，研究SSBI的统一工作原理，提出形成SSBI的推演方法，为不同SSBI的形成提供理论依据和方法参考，对电路拓扑学做了有益的尝试和补充；"直通"造成的开关损耗、电压过冲和振铃及EMI干扰是SSBI的共有缺点。本课题拟应用所提SSBI拓扑形成理论和软开关理论，推演出高性能绿色SSBI电路。预研究结果表明，软开关型SSBI能够大幅改善系统损耗和EMI环境，为新型高效绿色SSBI的发现提供理论依据和研究方向。

在燃料电池和光伏发电等清洁能源系统中，为了克服电源输出电压大范围变化的缺点，同时减少电源模块的串联个数以提高系统的安全性，电能转换电路（PCS）多采用高电压增益DC-DC电路级联电压源逆变电路（VSI）的两级电路结构。而两级结构增加了系统的复杂性和成本。以Z源逆变器(ZSI)和准Z源逆变器(qZSI)为代表的单级可升压逆变电路（SSBI电路），由于其高效节能、结构简单以及电路的安全可靠等优点而得到研究者的青睐。研究工作主要集中在SSBI电路的应用、高电压增益SSBI电路的提出等方面。本项目从SSBI电路的共性入手，揭示SSBI电路的统一结构及构成特征。从拓扑学的角度研究SSBI电路的特性、优缺点及应用场合。提出推演SSBI电路的两种方法，同时对比了两种推演方法的优缺点，找到了较合适的SSBI推演方法—广义SR-XSI推演法，从方法论的角度解决了高性能SSBI电路提出的盲目性。融合软开关相关理论，提出若干性能较优的软开关SSBI电路，该类电路减少了硬开关损耗及寄生电感和漏感等给SSBI电路带来的开关管电压过冲和振铃问题。SSBI软开关电路能够改善电路的电磁环境，并提高系统效率。从SSBI电路升压机理和升压因子的数学表达式出发，找寻减小直通占空比和调制因子相互制约的途径和推演高电压增益SSBI新型电路的方法。升压因子表达式中增加分子升压多项式是提高小占空比时电压增益的一个策略，为推演新型高升压比SSBI电路指明了方向。在该策略的指导下，课题组应用广义SR-XSI推演法找到若干高升压比SSBI电路，经过详细的研究、分析和实验，验证了理论的正确性和可行性。CWMV ZSI电路通过选择电容-二极管对的数量以及降压变压器的匝比来实现小直通占空比时的高电压增益。而SLSD- SLND ZSI电路通过选择三绕组耦合电感的匝比来实现小占空比时的高电压增益。两种电路的升压因子数学表达式中都增加了分子升压多项式，起到很好的升压功能。