Design Of Battery Monitoring System Based On STM32

With the continuous exploitation of traditional energy sources such as oil and natural gas,energy depletion and environmental pollution have become enormous challenges facing the world today,seriously restricting the healthy development of human society.With the continuous advancement of new energy technologies,it has become an inevitable trend for electric vehicles to replace fuel vehicles.Power battery is an important part to determine the performance of electric vehicles.Monitoring and protection of power batteries,extending service life and effectively utilizing battery energy are important driving forces for the popularity of electric vehicles.Therefore,battery management system(BMS)has become the focus of research.In the electric vehicle,the BMS is responsible for the state control,balance processing,state of charge(SOC)estimation,communicates with the vehicle controller and other protection control of each unit battery in the power battery pack.In this paper,the characteristics and several equivalent models of lithium batteries are studied firstly.The various estimation methods of SOC are compared and optimized.The extended Kalman filter method is used to SOC estimation,which is combined with the open circuit voltage method and the ampere-hour integral method.The derivation process was carried out and the simulation was verified by Matlab.Then,the lithium battery balance system is discussed and compared,combined with lucubrating of the existing BMS topologies,the voltage acquisition,current acquisition,temperature acquisition,balance processing,and communication methods.Based on the research above,an efficient and practical battery monitoring system is designed with the master-slave topology.The system uses STMicroelectronics' STM32F103C8T6 chip as the control core,and combines Linear Technology's LTC6804-2 chip.It innovatively integrates some of the modules of the master control unit into the slave control unit,so that the system board can be switched between the master and slave modes.The PCB design,proofing and welding board were completed successively.The C language program was written in the Keil integrated environment.The host computer program was written based on C/C++ in the Qt environment,and the feasibility of the design was verified by experiments.