Sathik M Jagabar, Almakhles Dhafer J
Renewable Energy Lab, College of Engineering, Prince Sultan University, Riyadh, Saudi Arabia.
Sci Rep. 2022 Mar 22;12(1):4924. doi: 10.1038/s41598-022-09008-z.
The boost-switched capacitor inverter topology with reduced leakage current is highly suitable for distributed photovoltaic power generation with a transformerless structure. This paper presents a single-stage 5-level (5L) transformerless inverter with common ground (CG) topology for single-phase grid-connected photovoltaic application. A generalized version of the proposed topology is also presented. The proposed topologies are derived by combining the dc/dc boost converter and switched capacitor cell. The primary focus has been given to the 5L version of the proposed topology. The number of switch counts is reduced, the maximum voltage gain is four times, and the inrush current is suppressed due to the input inductor configuration. Also, the voltages across the switched capacitors (SCs) are self-balanced. The negative source terminal and the load are connected directly to suppress the leakage current. It is thoroughly compared with other recent CG-Type topologies to attest to the advantages of the proposed topology. The laboratory prototype is developed for 600 W with the maximum efficiency is 94.21%, and the maximum source current is not more than 25A. Further, the operation of the proposed topology is verified under dynamic loading conditions, and the results are presented.
具有降低漏电流的升压型开关电容逆变器拓扑结构非常适合无变压器结构的分布式光伏发电。本文提出了一种用于单相并网光伏应用的具有公共接地(CG)拓扑的单级5电平(5L)无变压器逆变器。还给出了所提出拓扑的通用版本。所提出的拓扑是通过将直流/直流升压转换器和开关电容单元相结合而推导出来的。主要重点放在了所提出拓扑的5L版本上。开关数量减少,最大电压增益为四倍,并且由于输入电感配置抑制了浪涌电流。此外,开关电容(SC)两端的电压是自平衡的。负源极端和负载直接连接以抑制漏电流。将其与其他近期的CG型拓扑进行了全面比较,以证明所提出拓扑的优势。开发了600W的实验室样机,最大效率为94.21%,最大源电流不超过25A。此外,在所提出拓扑的动态负载条件下验证了其运行情况,并给出了结果。