Design Of Small Photovoltaic Power System

Due to the advantages of inexhaustible,renewable and clean,solar energy is becoming an important part of the world's energy.Solar photovoltaic power generation is also being paid more and more attention by the state.At home and abroad for the green environmental protection and requirements are increasing,sustainable development of clean green energy,and establish a new energy supply system,increase new energy accounted for the total national energy consumption ratio,reduce pollution,has become an important national energy strategy.Photovoltaic power generation has been included in the key development areas of the national energy development plan.The future of China and the global solar photovoltaic power generation will be very promisingSmall photovoltaic power generation system can effectively solve the problem of power supply in remote mountainous areas,islands and other non power areas,and also to a certain extent,alleviate the power shortage in the peak urban electricity consumption..This paper analyzes and studies the small photovoltaic power generation system from the following aspects:1.Analysis of photovoltaic power generation status and development prospects.It mainly includes MPPT technology,inverter grid connected technology,islanding detection technology.2.The maximum power point tracking(MPPT)is studied in detail.Several common MPPT algorithms are analyzed and compared,and an improved perturbation observation method based on variable step length is proposed.The simulation analysis is carried out under the MATLAB/SIMULINK platform.The simulation results show the correctness and feasibility of the improved perturbation and observation method based on variable step size.3.Overall design and analysis of small photovoltaic power generation system.On the basis of comparing and analyzing the advantages and disadvantages of traditional PI control algorithm,quasi PR control algorithm and repetitive control algorithm,this paper uses a single cycle-PI based grid inverter control algorithm,and carries out simulation analysis to verify its effectiveness.4.The hardware module of the small photovoltaic power generation system is analyzed and designed.The core control part and data collection part of the system are analyzed and designed in detail.The corresponding software flow design is given.The prototype of the inverter connected to the grid is made and tested.The test results reach the conditions of the grid.