The Development Of High-frequency Isolated Photovoltaic Grid-connected Inverter

In the future, grid-connected photovoltaic system is the important form of photovoltaic application. Grid-connected inverter is the core of the system; DSP is used as the control chip in the PV inverter. A 3kW high frequency grid-connected inverter is designed at the end.Hardware design is presented in detail in the paper, as how to choose the IC and how to deal with EMC. Several current control methods are discussed in the paper, each method has its virtue and defect, at the end, the SPWM technology is applied in the system. And the flow chart of the main program is also presented in the paper.Some MPPT control methods are discussed in this paper. We get better result with the proved Perturb&Observe algorithm in the experiment. Islanding phenomenon is introduced and the harm to the grid is discussed. A few anti-island methods that can detect the Island phenomenon are discussed. At the end of the paper the conclusion is given.