A New Cross-Six Inverter for Transformerless Grid-Connected Photovoltaic Systems

This article proposes a novel cross-six (X-6) inverter topology for low voltage distributed grid-connected solar photo-voltaic (PV) systems that operates transformerlessly. The proposed topology’s primary feature is that it significantly reduces the effects of common-mode leakage current in existing inverter topologes used in transformerless operation. Since the leakage current is reduced with the proposed X-6 inverter topology, it improves the power quality and switching losses as these are directly related to the leakage current. The performance of the proposed X-6 inverter employing on a single-phased grid-connected PV system is determined in the MATLAB/SIMULINK platform and compared with different existing transformerless inverter topologies used for similar applications. The comparative simulation results are presented and discussed in terms of total harmonic distortions (THDs), leakage current, and efficiency. Simulation results demonstrate that the proposed X-6 inverter topology has the ability to achieve an efficiency of 98.34% while injecting current into the grid with lower values of THDs.