Comparison between 2-level and 3-level grid connected inverters implemented using SRF PLL technique

In recent days in order to have effective utility of Renewable Energy (RE) Resources, they are being integrated to the Grid through a power converter. So, the grid side inverter control of RE systems is one of the main issues in power production units besides that, the voltages and the currents that are being feed to the grid must be free from harmonics and they should have the same phase angle as that of the grid. The THD of the inverter output voltage can be reduced by increasing the step level of the inverter topology. In this paper a comparative study between the 2-level & 3-level inverters that are interconnected to the grid is studied by using the SRF-PLL technique and the results have shown that the amount of THD for the 3-level topology is less, compared to that of the 2-level topology.