Photovoltaic grid connection power generation system based on DC converter and working method thereof

The invention provides a grid-connected photovoltaic power generating system based on a novel direct current converter and a working method of the grid-connected photovoltaic power generating system. The grid-connected photovoltaic power generating system is characterized in that the grid-connected photovoltaic generating power system consists of a direct current converter, a grid-connected inverter, an isolation transformer and a control circuit; the working method comprises the steps as follows: 1. collecting signal; 2. MPPT module data processing; 3 applying an MPPT arithmetic; 4 inverter module data processing; 5. applying a grid-connected arithmetic; and 6. applying SPWM arithmetic. The grid-connected photovoltaic power generating system and the working method thereof have the advantages of small technical realization difficulty, obviously reducing the cost, flexible installation, convenient maintenance, high voltage and current detection precision, advanced control arithmetic, quick running speed of control chip, the system being capable of obtaining excellent tracking precision and stability, combining the hardware device with the software programming of a digital signal processor, simple design, low cost and easy realization of the hardware device, brief and understandable software programming arithmetic.