Estimation Of State Of Charge Of Electric Vehicle Battery And Implementation Of Battery Management System

In recent years,the serious problem of air pollution has prompted people to continuously improve their environmental awar eness.Travel tools have changed from fuel vehicles to electric vehicles,so electric vehicles will have a broad sales market.The battery pack is one of the core facilities of electric vehicles.Its working status and reliability are undoubtedly an import ant basis for the safe operation of vehicles.Based on this practical value,this paper designs a BMS integrated machine,in which BMS refers to the battery management system.The focus of this research is battery SOC estimation,that is,state of charge estimation,detailing battery model screening,corresponding internal parameter identification,accuracy verification after applying parameters,comparison and selection of battery SOC estimation methods,the simulation diagram construction of SOC estimation and its engineering implementation process.Throughout the process,a variety of battery models,model parameter identification methods,and battery SOC estimation methods were reviewed through the literature.By comparing the accuracy of various method s and the actual requirements of hardware software implementation,a method combining both conditions was selected..After verifying the accuracy and feasibility of the SOC estimation method,an integrated hardware platform is designed to implement the method.The all-in-one hardware platform designed in this paper takes NXP's automotive-grade DSP chip as the core,and cooperates with the external hardware circuit and the AD conversion function of the chip itself to complete the acquisition tasks of temperature,current and other analog quantities.The implementation logic implements SOC estimation through the C language on the all-in-one hardware platform.Finally,the platform has completed the function of measuring the remaining battery capacity,monitor ing of the insulation state,current,voltage and temperature alarms,as well as the battery charge control and the unit power balance during the working process.In order to facilitate the debugging and verification of the function of the integrated machi ne,this paper uses Qt to design the debugging software of the upper computer.It can transmit and analyze the related information collected by the integrated machine through the CAN bus,which greatly improves the development and debugging efficiency of the integrated machine.After the simulation and engineering verification,the BMS integrated machine designed in this paper can complete the monitoring of the battery pack status.At the same time,the SOC method realized in this paper can meet the actual engineering requirements in both estimation accuracy and operation speed.Therefore,the research in this paper BMS integrated machine has certain practical application value and significance in the state monitoring of electric vehicle battery pack.