Research And Design Of A Battery Equalization Charging Device And Control System For Photovoltaic Complementary System

With the reduction of non-renewable energy sources,the problems arising from the energy competition gradually appear and need to be solved urgently.As one of the most promising new energy sources in the world,solar energy is essential to solve the problem of energy shortage.However,it is necessary to provide energy supplement by weather conditions.In this paper,the electricity as a supplementary energy,a photovoltaic and electric complementary device is designed,for which the equalization charging module was studied.Combined with the existing equalization methods and strategies,a lossless equalization circuit and a new equalization strategy are designed to achieve the charge balance of the series battery pack.This paper summarizes the research status of battery balanced charging at home and abroad,introduces the composition and working principle of photoelectric complementary power supply system,and expounds the importance of the battery in three aspects: photoelectric energy storage,time sharing price and load priority.Taking lithium battery as the research object,because of its inconsistency,the necessity of balanced charging is expounded.Taking lithium battery as the research object,this paper analyzes its inconsistency,and expounds the necessity of its equalization charging.According to the charging curve of lithium battery,a three-stage charging methodconstant current-constant voltage-trickle current is designed.This paper analyzes the existing methods and strategies of equalization charging,and puts forward a balance method to bypass the overcharged single cell by using the IGBT switch based on the terminal voltage of the single battery.In this paper,the hardware and software design of the balanced charging system is carried out,and the lossless equalization circuit is analyzed emphatically,and the key components are selected and parameterized.The hardware system based on single chip microcomputer includes the main circuit,the sampling circuit and the power supply.The software adopts the modular design,and gives the main program and the subroutine flow chart.This paper designs a simulation circuit based on Saber,builds the simulation model,completes the charging simulation of four series batteries,records and analyzes a large amount of data,proves that the designed method and strategy meet the equilibrium requirement.The paper also carries out two series of lithium battery balanced charging experiment,and the experiment results provide powerful help for the design of this balanced charging system.