Simulation Of Photovoltaic Inverter Grid Based On Three-phase Phase-locked Loop And SVPWM

In nowadays,with the rapid development of science and technology, energy shortage hasbecome a hot topic of public concern. Wind, solar and other renewable energy sources havebeen widely used. So, how to convert solar energy into electrical energy for storage andcombining to the grid has become a problem to be solved iny the photovoltaic field.Firstly, the article describes the historical background of the photovoltaic powergeneration at home and abroad, the prospects for development, and gives the PV inverter andgrid standards；Secondly, it makes an introductory of the basic theory of the inverter and thegrid, that is phase-locked loop and the PWM principle;Again, it makes a very detailedanalysis and presentation of the core technology used by the three-phase photovoltaicgrid-connected inverter-three-phase phase-locked loop and SVPWM principle. Three-phasephase-locked loop includes two very important coordinate change——three-phasestationary coordinate system to convert the two-phase stationary coordinate system of theClark transform and two-phase stationary coordinate system to the two-phase rotatingcoordinate system of the Park transformation. It makes a detailed description of the basicprinciples and the derivation of the SVPWM technology.Using SVPWM principle, thearticle derives which sector the space vector Uref is in, as well as calculates the time Urefrole in each increment, and then obtained the inverter drive signal by using it, achieve theinverter. In the last of the article, some analysis of three-phase photovoltaic grid-connectedinverter control strategy are made,and the various modules of the system are set up andsimulated by using MATLAB/SIMULINK. Through the analysis of grid-generated currentwaveform and hard power, reactive power and power factor, the correctness and practicalityof the control strategy are verified.