Design And Development Of Batteries Management System

The storage battery is an important equipment in DC system. It’s necessary to maintain the storage battery in a scientific and efficient way. The battery management system(BMS) can monitor operating conditions of battery or battery pack in real time, manage battery charging and discharging by intelligent management, whose conventional protection functions includes high and low voltage, high-low temperature and overload short-circuit. It can estimate the residual power of battery, compute system endurance, balance the battery capacity, diagnose battery health and prolong battery life. The battery management system (BMS) is a focus of current research, and also has great research value and some room for improvement. It’s urgent to make innovation and development for the battery management system. Based on this background, The research work of this thesis is about the battery management system (BMS). This paper summarizes the basic function, BMS real time data acquisition, basic protection and fault alarm, residual quantity calculation, historical data management and so on. It compares the technical points of each function, raise an open circuit voltage method and ampere hour measurement corrected passes parallel feedback algorithm, the design and implementation of a real time control system based on integrated power calculation. This paper mainly includes the following aspects:Firstly, the thesis analyzed and summarized the characteristics of the battery, and described the common methods and the predicted difficulties of the battery state of charge (SOC).Secondly, this thesis studied SOC estimation method of the battery. In this part, it elaborated the ampere hour measurement, revised SOC by means of current, aging and temperature, described the process of extracting the equivalent current coefficient, then, described the open circuit voltage method, and finally put forward an ampere hour measurement and open circuit voltage method combined with parallel weighted feedback algorithm, in order to realize the estimation of battery SOC.Thirdly, the thesis designed the hardware circuit. At first it designed the function of battery management system. Battery management system includes the following aspects:the battery voltage, current, temperature, periodical inspection of time parameter, charge and discharge management, conventional protection, fault alarm, estimation of residual battery capacity, diagnosis of battery health, history data management, network communication, status display and button input. On the basis of the above characteristics, this research designed a battery management system based on STC12mcu. The main hardware modules include:the main control module, battery voltage, current, temperature, time and other parameters acquisition modules which take STC12as the core, LCD refresh timely display module, RS485and upper computer communication module etc..Finally, the thesis completed the software programming. The software design is divided into the following parts:main control part, real-time data acquisition part, data processing part, communication part and the input and output part. We tested the battery management system. The experimental data show that, the accuracy of sampling is high and the process is safe and reliable, which achieve the desired goal.