Renewable energy sources such as solar, wind are becoming more popular to generate power. These renewable energy based power generation systems generate DC power output. An inverter is needed to convert DC power from renewable energy sources into AC power. These renewable energy sources are connected to the grid through interfacing converters which supply active and reactive powers to the main grid. Inverters are either be connected in standalone or in grid connected mode. In the case of grid-connected mode, the output voltage and frequency of inverter should be same as grid voltage and frequency. If loads connected to the grid are non-linear in nature, then it can introduce power quality problems such as harmonic distortions in grid voltage.