Non Isolated Multi Port Inverter with Reduced Common Mode Leakage Current and Minimum Phase Property

Abstract

A non isolated type multi port inverter with minimum phase property and finely suppressed common mode leakage current for solar photovoltaic (PV) power processing is presented in this article. To avoid the limitations of solar PV based galvanically isolated systems like reduction of overall efficiency, increase in size and cost of the system this non isolated multi port inverter is proposed. However, these non isolated type solar inverters have limitation of flow of more dangerous common mode leakage current, when either it is connected to the grid or its neutral point is connected to the ground. Therefore, to suppress this current, a unipolar type sinusoidal pulse width modulation technique is implemented in this work; so that the high frequency components of common mode voltage across the PV to ground stray capacitor is remained zero throughout the complete switching cycle. Further, the minimum phase property of the proposed non isolated multi port inverter is verified, which results simpler controller design, higher loading capability, and also it gives faster response during sudden change in load or duty ratio value. Ultimately, the various claimed points of the proposed non isolated multi port inverter are validated by simulation and experimental analysis. © 2024 IEEE.