Development Of The Micro-converter Based On The Three-phase Grid-connected Solar Photovoltaic Power System

With the intensification of energy crisis,many countries pay more attention to New Energy Generation Technology,especially to speed up the exploration of Photovoltaic Power Generation System.Micro-converter plays an impotant role in the System.Therefore,it has practical significance to deepen research on micro-converter.Firstly,this paper introduces the generating principle of Photovoltaic cells and output charaeter of Photovoltaic cells.Meanwhile,this paper introduces the advantages and disadvantages of Boost converter,Flyback converter and Forward converter.Secondly,this paper analyzes the working characteristics of the interleaved Boost Converter deeply,and derives that the output current ripple of the interleaved Boost Converter is lower than the traditional Boost converter by simulation.Thirdly,this paper analyzes the working characteristics of an improved redundancy DC/DC Converter under different working conditions(an normal circuit,a short circuit and an open circuit)by simulation.And derives that control system can refresh the system to the normal state,when the DC/DC Converter have fault(a short circuit or an open circuit).Finally,this paper researches an improved isolated boost with active clamp circuit,and analyzes its work principle and power flow.Meanwhile,the Three-phase Grid-connected Solar Photovoltaic Power System simulation platform based on the improved converter is built.And the improved converter can accomplish Maximum Power Point Tracking in the system.Based on the above research,the hardware platform of Boost converter is built.Its output power is 250W.And because of the hardware platform composed of Boost converter and its control system,it has smaller volume and can be mounted conveniently.Meanwhile,the hardware platform of three-phase grid-connected Solar Photovoltaic Power System and its control system are built.Finally,this paper integrates the hardware platform of Boost converter and the hardware platform of Three-phase Grid-connected Inverter Solar Photovoltaic Power System.The output voltage and current from Photovoltaic cells can flow into gird by analyzing a large amount of experimental data and improving control strategies.Moreover,the efficiency of Boost converter is 97.6%.