Improved main circuit structure of photovoltaic synchronization inverter

The invention discloses an improved main circuit structure of a photovoltaic synchronization inverter. The improved main circuit structure comprises a photovoltaic (PV) battery board, a capacitor Cin, distributed capacitors C1 and C2, a non-isolation direct-current/direct-current (DC/DC) converter, a capacitor C, an H bridge consisting of power switching devices V1, V2, V3 and V4, and diodes D1, D2, D3 and D4 which correspond to one another one to one, an afterflow loop on the voltage positive half circle of a power grid consisting of a power switching device V5 and diodes D5 and D7, an afterflow loop on the voltage negative half circle of the power grid consisting of a power switching device V6 and diodes D6 and D8, a filter circuit consisting of inductors Lf1 and Lf2 and a capacitor Cf,and a common mode resistant voltage filter H-bridge capacitor group consisting of capacitors C3, C4, C5 and C6. A synchronization inversion circuit for executing the improved main circuit structure has the advantages of capab