The Research On Methods For Grid-connected Photovoltaic Synchronization And The Design Of A Switch Circuit

With the rapid growth of social economic scale,the vast development and consumption of the traditional energy has lead to greater energy depletion and environmental pollution problem.Thus human have paid more and more attention to new energy.Among those new energy,solar energy comes into people’s sight for its advantages.The photovoltaic power generation,which is an important way to harvest solar energy,has rapidly developed,and became the focus of the application research subject of new energy. Grid-connected photovoltaic(PV) inverter,the core equipment of grid-connected photovoltaic power system,converts electrical energy,playing a crucial role in overall system’s efficiency, stability. Therefore, in order to improve the generating efficiency and control ability of grid-connected PV power system, researching a high-performance grid-connected PV inverter control method has an important significance.The application of LMS Self-adaptive Filtering in grid-connected photovoltaic synchronization and Linear Feedback in photovoltaic microgrid synchronization are researched and the design of a switch circuit is designed in this paper. The main research work are as follows:Firstly, the main circuit-topology-structure of the single-phase full-bridge photovoltaic (PV) grid-connected inverter is studied;The operating principle of the Boost conversion circuit and the full bridge inverter circuit are analyzed; PID control algorithm is thoroughly studied.Secondly,LMS self-adaptive filtering theory is studied,then come up with a method to apply LMS self-adaptive filtering to photovoltaic (PV) grid-connected inverter;Matlab/Simulink simulation model is built based on the method;The results shows that the new method distinctly improved effects in current tracking,steady-state error and THD.Thirdly,the application method of Linear feedback in photovoltaic is thoroughly researched and its performance is tesed via Matlab simulation.Last,a tentative plan of photovoltaic power switching circuit is given,then the hardware and software is designed,finally the prototype circuit is made.