Research On Battery Management System For Electric Vehicle

Electric vehicles lead the development of automobile technology, the modern electric vehicle with low emissions or zero emissions, low radiation, low noise and environment-friendly and energy saving is a new vehicle of environmental protection. It is sustainablly developed from the late 20th century and has broad prospects. The battery and its management system as the main power source are one of the most important links in the industrial process.Battery management system, which can achieve real-time monitoring of battery parameters and estimate the state of charge (SOC), provides the SOC, range reaches and other information for the driver and prevent the battery from over-charging, over-discharging, over-voltage,over-current,over-temperature which directly determine the life of battery. A good battery management system which exerts fully the superior performance of battery can also give the best protection to the battery, ensure the performance of battery, extend the life of battery and reduce the operating costs of electric vehicle.This article introduces the development of electric vehicles as well as the domestic and international overview of the development in battery management system for the urgency and importance of Battery management system; introduces the estimation methods, the advantages and disadvantages of SOC and then put forward the fuzzy logic theory which combines the hardware features and the use of its environment, on which based a fuzzy logic based SOC prediction model and the corresponding modeling process and simulation results. Equalization management is one of difficulties, In the analysis of existing balance method, use a new method based on Infineon Technologies balance management. Adopt Transformer storage energy ideas, and it can be achieved by the partial charge-discharge. This article also proposes master-slave battery management system for the difficulties of battery management system, amplifies details of the design of hardware interface circuit with the measurement modules, motherboards controlling module, CAN communication module. The corresponding software design of various hardware modules is proposed based on it and improvements of the system's software anti-disturbance capability are made by the introduction of second-order Butterworth filter.System Online testing and hardware-in-the-loop simulation test results show that SOC in the fuzzy prediction meets the system accuracy requirements. Experiments also show that voltage, current, temperature and other data errors are within specified limits, the total voltage error is less than 0.5%, the total current measurement error is less than 0.5%, and the temperature measurement error is less than 0.5℃. It meets the design requirements.