Modeling And Simulation Of Photovoltaic Grid Connected System

With the mass consumption of traditional fossil energy, the energy crisis has become more and more serious. The environmental problems caused by the use of a large number of fossil fuels are deeply troubling us and promoting the development of new renewable and none-polluting energy, especially the development of wind power and photovoltaic. Because of solar energy universality, photovoltaic power generation technology has become a hot research direction. The continuous progress of power electronic technology and the continuous decline in the cost of photovoltaic cell make it possible to transform photovoltaic power generation from complementary energy to alternative energy sources. Because the power density of the cell plate is becoming higher and higher, the grid connected operation has become an important operating mode of photovoltaic power generation. The research object of this paper is the control system of photovoltaic grid connected and the paper main task is to study the control system of grid connected photovoltaic.In this paper, the mathematical model of PV array is analyzed, the model of PV array is built with a more practical model of behavior; Aiming at the problem about maximum power point tracking control of PV array, a maximum power point tracking control method based on fuzzy control is proposed, this method is compared with two kind of traditional methods; this paper expounds the working principle of the three-phase voltage source inverter and SVPWM control theory, and Simulink is used in the modeling and simulation of SVPWM;Aiming at the resonance problem of LCL type filter, three kinds of passive damping control modes are compared; In order to control the grid current, grid voltage oriented vector control method is elaborated and the control system how to use the PI controller in DQ rotating coordinate system to achieve therealization of decoupling active component and reactive component is analyzed,Simulation is used to verify the feasibility of the control system; the coordination control theory of the two stage system of photovoltaic grid connected power generation system is described, and the model of coordinated control system is built to verify the rationality and feasibility of the pre and post level coordination control mode.