Photovoltaic Micro-inverter

Today, in the face of the continuous development of science and technology,electrical product’s variety and quantity, which grow with each passing day, accelerated the natural exploitation of non renewable energy use rate. In order to ease the global energy crisis, which people have to consider the development of new renewable energy, photovoltaic grid-connect system appeared which have opened up a new way for human to use new energy,photovoltaic has become the trend of development. The rise of the development of building integrated photovoltaic and family of photovoltaic grid-connected system,which makes the micro grid-connected system based on a single photovoltaic panel,with his unique flexible networking, convenient and small size and other advantages, has been used more and more widely. Micro-inverter is the important part of the photovoltaic grid-connected system, whose work efficiency, output waveform quality will directly determine the performance of the system. It has great realistic significance to study on the micro-inverter.This paper mainly discusses the interleaved flyback-type micro-inverter design.Firstly, it describes photovoltaic grid-connected system background and the researching status of micro-inverter in chinese and international market. Secondly, it analyses the interleaved flyback working principle and describes the key parameters. Also, the micro inverter output waves were simulated through MATLAB simulation software. There is an introduction on the hardware circuit of the inverter, such as switch tube selection, drive circuit designing, sampling circuit on DC&AC. The paper has micro-inverter software design introduction together with the key control flows, the screen shots of oscilloscope and the MPPT on synchronization. All the software verification of micro-inverter are based on the interleaved flyback hardware platform which is controlled by DSP TMS320F28035 chip. The hardware platform test result shows that this hardware design could meet the needs of micro-inverter grid-connected requirement.