A topology review and comparative analysis on transformerless grid-connected photovoltaic inverters and leakage current reduction techniques

Photovoltaic energy source growth is significant in power generation field. Moreover, grid connected inverters strengthen this growth. Development of transformerless inverters with higher efficiency, low cost and size is competitive than the inverters with transformers. However, leakage current generation in transformerless inverters is a challenge to their growth. The research in evolution of new transformerless inverter topologies with higher efficiency, boosting capability, and reduced leakage current is interesting. This paper presents an extensive discussion of transformerless inverters under the categorization of their structures and the subcategorization with leakage current reduction techniques. The components and connections of inverters are differentiated with colours for the effortless understanding of operation. The detailed comparisons of transformerless inverters based on performance and construction are also presented with their strengths and weaknesses. To give deep intuition on characteristics of transformerless inverters, selected inverters are simulated with different operating conditions. Loss contribution of each switch in the selected inverters is analysed, to help the new researchers, designers and engineers to design efficient topologies.

Automated summary

This paper extensively discusses the categorization of transformerless inverters and techniques to reduce leakage current, and compares their performance and construction. By simulating the inverters under different operating conditions and analyzing the loss contribution of each switch, it provides a deep intuition for designing efficient topologies to new researchers, designers, and engineers.