Simulation And Research Of Photovoltaic(PV)grid Inverter Based On DSP

The world is now rapidly transforming from an industrialized society to a low carbonsociety，therefore, the development of green energy has become a major issue.Energygenerated from photovoltaic power system is developing into an important part of theworldwide green energy because it is renewable,clean,inexhaustible and so on. Therefore, inthis paper, the photovoltaic (pv) grid inverter has been introducted in detail, system controlalgorithm, system simulation, software and hardware design has been thoroughlyresearched.Firstly,the maximum power point tracking (MPPT) technique is one of the keytechnologies of photovoltaic power generation system. So this article first study severalkinds of maximum power point tracking methods, combining the two levels of photovoltaicgrid topology for overall simulation and analysis. Former level implementation MPPtracking, and the latter inverter grid are made to be independent in order to improve thereliability of the control system. This article models and simulates the system inMATLAB/SIMULINK,presents different methods of MPPT control respectively, comparesand analyzes the simulation results as well. System Simulation makes the system runs inunity power factor status thus we can get a safe, reliable and efficient grid.Secondly,the high power solar photovoltaic power station is the inevitable developmenttrend of clean energy in the future,thus at the same time, this paper has a detailed studyand analysis on the principle and control strategy of three-phase grid inverter.Consideringthe control strategy based on grid voltage orientation needs complex decoupling and is fairlysensitive to harmonics of power grid, so on the basis of Traditional grid voltageorientation,this article adopts the strategy of fixed-frequency SVPWM and Direct PowerControl. By introducing the concept of virtual flux, estimating the virtual flux,andcompensating error on the basis of traditional virtual flux,this article realises the goal ofcontrolling the grid inverter without ac voltage sensors, presents the modeling andsimulation of two control strategies and analyses the corresponding simulation results.In the end, the paper designs hardware and software circuits of the PV grid-connectedinverter system.However, take the imperfection of the laboratory conditions and safetyfactors into consideration,in this paper, I will take the the hardware physical topology ofsingle-phase non-isolated photovoltaic inverter. The principle of main hardware circuitdiagram is given in detail. The principle of DDS technology and the realization of SPWM modulation method and the program design flow chart of the system is expounded.Combining all the hardware circuits, TMS320F2810is used as the core chip. Frequency andphase tracking is realised by using DDS technology; The validity of the theory is verified bydebugging on hardware platform.