Research And Design Of 2kW Single-phase Photovoltaic Grid-connected Inverter

Since the beginning of the 21 st century,with the depletion of fossil energy and the increase of environmental pollution.Governments and scholars from various countries have begun to pay attention to and develop clean and renewable energy.Now the use of renewable energy has become a development trend.As a renewable and clean energy,solar energy has the characteristics of being renewable and non-polluting,and its development and utilization have been paid attention by scholars.As the core device of solar photovoltaic grid-connected system,photovoltaic grid-connected inverter has extremely high development and research value.This article first compares the advantages of solar energy and other renewable energy sources,and analyzes the development status of photovoltaic grid-connected inverters at home and abroad.The main circuit topology and common control methods of the existing photovoltaic grid-connected system are analyzed.In this paper,the main circuit of the three-phase photovoltaic grid-connected inverter is finally adopted the DC / DC Boost boost circuit cascaded fullbridge inverter DC / AC grid-connected inverter structure.Closed-loop control control method.And elaborated the photovoltaic solar photovoltaic cell’s working principle and the equivalent output circuit and the output PV characteristic curve.And comparative analysis of several MPPT control methods.The hardware circuit of this paper takes DSP2808 as the main control chip of the controller.The designed hardware circuit mainly includes: main control circuit DSP2808 and power circuit,drive protection circuit and auxiliary sampling circuit,output interface LC filter.The software design of the control system mainly designs the main program,interrupt service program,and SPWM wave subprogram of the system,and gives the software software flow chart.Based on the above design,this paper builds a simulation model of 2k W photovoltaic grid-connected inverter in Simulink.The simulation results show that the working performance of the inverter can meet the design requirements of the grid connection,and fully verify the rationality of the design.