Research Of The Battery Management System For Electric Vehicle

In today's society,the problem of energy crisis and environmental pollution is increasingly outstanding,which directly affect the people's living standards and the economic development.In recent years,the amount of the car has increased year by year,mankind has entered the era of the car.As a means of transport,it is convenient for our daily travel,but also added a lot of trouble.Large-scale automobile exhaust emissions cause a serious air pollution,which is forcing us to develop new energy vehicles quickly,to improve the surrounding environment and alleviate the shortage of energy.This paper mainly research the battery management system for electric vehicles,the purpose is through monitoring the running state for lithium-ion batteries,to make the corresponding control,and improve the utilization rate of the battery and prolong its service life.In this paper,we first introduce the battery management system includes the main function and the current research status,then analyzing the characteristics of the lithium-ion battery and inconsistency,the monomer voltage acquisition and balance control were described in detail.On this basis,the design of the MC9S08DZ60 microcomputer as the core of battery management system,including the LTC6802 chip monomer voltage acquisition,using DS18B20 chips for the collection of temperature,using CAN communication module to complete the transmission of information in the battery management system.Battery SOC estimation is another key content of this study,this paper lists several common SOC estimation methods,through the analysis,we can find some method does not apply to estimation of SOC under current conditions,and puts forward a method based on law of conservation of energy of SOC estimation method.Draw the estimation formula of instantaneous remaining power batteries,and according to the relationship curve between the battery capacity and cycle times,temperature and self-discharge,to make the appropriate correction and compensation.Finally through simulink module of MATLAB to build battery equalization control and residual capacity estimating model,and associated off-line simulation model to simulate actual working conditions of electric vehicles.According to the results obtained by simulation analysis,to verify the balance of the presented control strategy and the feasibility of the soc estimation method.