The Bms Study Of Vehicle Power Rechargeable Battery Pack

As the environment pollutions become more and more serious,the automobile industry is transformed and upgraded through the development of science and technology.The new energy vehicles,especially electric vehicles,has made the country more likely to build a strong auto industry through electric cars.One of the most important parts of electric cars is the power rechargeable battery pack.Because the inherent safety of lithium-ion batteries,battery chemistries natural chemical reaction is difficult to predict and estimate the problem such as,making for lithium battery design and research of battery management system has been greater difficulties.Excellent BMS(Battery Management System)is of great significance to promote the use of electric vehicles,reduce manufacturing cost and improve safety.Because of the lack of research on the application of electric cars in need of large current charge and discharge,there are still some defects in BMS system at domestic and abroad,and there is still a lot of room for improvement.The research on battery SOC(state of charge)and SOH(SOH,state of health)is currently in the field of further study.For electric vehicle rechargeable battery pack in this paper a set of independent unit for the study of the smallest unit,by studying the basic characteristics of lithium battery and advance to the lithium battery SOC estimation algorithm and monomer lithium battery balanced strategy research.In this paper,BQ76940 is used as the analog front-end,and STM32F103VET6 is the BMS hardware circuit of the control core,which realizes the BMS design of the power battery pack with up to 15-series.And designed the software based on the hardware in embedded real-time operating system uC/OS II as the core,contains a lithium battery SOC estimation,monomer voltage balancing,temperature control,communication function.A simple and effective single battery equalization strategy is used in the software,and the SOC estimation algorithm is implemented to realize the fusion open-circuit voltage method,current integration method and extended kalman filter method.