Various Non-Isolated Three Phase grid-integrated PV Inverter Topologies for Leakage Current Reduction - A simulation-based study

Abstract

Non-Isolated grid-integrated inverter configurations are vastly preferred due to their high efficiency, low cost and compatibility with the system. The main downside of the system is galvanic isolation, leakage current (LC) minimisation, and reactive power compensation. Galvanic isolation and leakage current reduction in non-isolated inverter configuration mainly depends on inverter structure and modulation techniques. Based on these issues, several single-phase grid-integrated inverter configurations are developed and reviewed. Compared to single-phase inverter topologies, there are very few studies on three-phase inverter topologies. Hence, in this paper, several three-phase inverter topologies are reviewed based on AC and DC clamping isolation, hybrid isolation with modified discontinuous pulse width modulation technique on LC reduction, current THD, and the strengths and weaknesses of the structure. Finally, simulations are carried out in MATLAB/Simulink for different inverter topologies.