Design And Study On Ni/MH Battery Management System

As a green and efficient transport in the world, hybrid electric vehicles has a growing interest and promising market demand due to energy and environmental concerns. China is gradually becoming industrialized in the early stages with good prospects for development. The Ni/MH battery pack is one of the key components in the drive system of electric vehicles as a supplemental energy source. Monitoring the dynamic characteristics (voltage,electric current, pressure,temperature) of Ni/MH batteries and estimating the battery state-of-charge (SOC) will be beneficial to maintain the good performance and extend the life of Ni/MH batteries. It has a great theoretical and engineering application.Based on the design and implementation of digital signal processing chip TMS320LF2407 in battery management system(BMS) hardware platform, the design of seven ways Ni/MH BMS has been finished. The study has expanded the kernel and external interface circuit of TMS320LF2407, exploring its internal A / D conversion module and CAN communications, designing the control of the physical connection and taking effective measures to hardware interference. Observing the total, single battery voltage, battery temperatures and the diversification of pressure, BMS has been chosen a temperature sampling with 18B20, which is digital and produced by DALLAS . The pressure sampling is acquired by PC10-9 sensor, which is able to bare high temperature and causticity. The research on voltage sampling has compared the merits and demerits of many kinds of sampling methods. It also showed the trend of voltage sampling.Depended on C language of software platform, the designed BMS has managed to anticipate functions of the division with hardware interrupt service procedures. The program completed the collection of voltage, temperature and the estimation of SOC. The study realized the battery-state detection, condition assessment and communication with PC. The precision of battery voltage , electric current and pressure sampling all achieved technical requests.