The Research And Implementation Of Li-Ion Power Battery Management System

With the development of technology and the urgent need for energy-saving environmentalprotection, the new energy has become an important direction of development for states energystrategy. Lithium-ion battery as one of the hallma rks for energy-saving environmental protectionhas been used as middleware in electric vehicles,Backup Powe(r UPS)and photovoltaic Inverter,provid ing the convenient for these industria l applica tions and power requirements. In response tothis situation, we took the lithium-ion power batteries that used in electric vehicles as theresearch object in this paper, giving full considera tion to the differences of battery monomer andgroup technology, and then designed the eight power battery ma nagement system.In this paper, I firstly had a detailed study in the structure of lithium iron phospha te battery,the charge-discharge characteristics,the charge-discharge method and the estimation of batteryrema ining capacity(SOC). Considered the actual applica tion needs, I established the part of thesystem design. Then I proposed TMS320F2812 to be the core of the control as overa ll controlunit. This dissertation has detailed analyzed the system requirements, designed a various partsfunction of the system and divided into hardware design and software design.Hardware design part: After detail introducing the power supply,Clock Reset,AD Sample,Communica tion mecha nism function and so on about the DSP core control system, I divided thecontrol external circuit into four major modules:the charging unit modules used the design ofsingle-chip switching power supply, provid ing energy source for the entire battery packï¼›Detection module is the front of the entire system, prima rily responsible for detecting thebattery's temperature,voltage and current to provide the data based for estimating the SOC ofbattery packï¼›Protection module is the assurance of the entire battery pack that can safe workingin charge-discharge process, provid ing the security mecha nism for the entire studyï¼›Balancedmodule is the important part of dissertation, the odd-even bala nced module that proposed hasma ximized the function of the equilibrium within the limited range of the protection module mecha nism, provided a good mecha nism for improving the efficient use of battery pack andextend ing the battery life, that's also the purpose of writing this article. According to the systemrequirements executed the anti-interference and low-power design.Software design part:using the embedded and enhanced C la nguage to write, modularprogramming, using the program structure and scheduling mecha nism that provided by T1company respectively completing the algorithm of each module, and present the correspondingflow chart. Combined the watchdog module and software anti-interference technology of theTMS320F2812, designed the correspond ing software filter and process specifications to ensurethe software system's legitimacy and stability.In the end, the BUCK converter is used to achieve consta nt voltage and consta nt currentstrategy in the charging procedure, completing the board development and do the integrateddebugging for system hardware and software. The experimental results show that this system hasbasica lly achieved the expected dema nd and the odd-even equaliza tion strategy showed goodresults, satisfying the applica tion requirements of the lithium-ion battery ma nagement system.