Solis three-phase S5-GR3P (3-20) K-4G grid connected solar inverter, which inputs the direct current generated by the solar panel and uses power semiconductor devices for high-frequency switching through a DC/AC conversion circuit to invert the direct current into three-phase alternating current. Further filtering out harmonics through a filtering circuit to make the output current purer. Finally, the grid control circuit ensures matching with the grid voltage, frequency, phase, etc., achieving efficient and stable grid connection.