Small Stand-alone Photovoltaic Power System Analysis And Design

As the increasing consumption of fossil-fuel energy,the world-wide energy crisis and environment pollution is becoming a critical problem.In all kinds of renewable and environment-friendly energies,solar energy has its unmatchable advantages and so causes more and more concern in science and technique field.The research about photovoltaic power technique and application now is very important for world's future development, especially for our country.This paper mainly focuses on stand-alone PV power system,firstly introduces the four basic parts of the system:solar cell,battery,DC-DC conversion circuit and control circuit,analyzes in detail the basic theories and relative characteristics.An example design of solar energy lighting system is taken in order to analyze the methods of the type chosen and parameter calculation of relevant elements,and then simulation experiments are made to test the function.The core part of this paper is to realize the charging of the battery through maximum power point tracking control.Based on the analysis about the output characteristic of solar cells and the require of battery's charging control,this paper discusses methods of maximum power point tracking,and then designs the proper DC-DC conversion circuit. According to system requirement,the improved perturbation and observation method based on the designed boost converter is established,and the whole design of the system is finished.