Design And Study Of HEV Power Battery Performance Testing System

With the development of the society, some issues on resource and environment have been more and more important. As a kind of green, efficient vehicle, HEV (Hybrid Electric Vehicle) has become a new focus in the automobile industry. As an auxiliary power resource, the power battery is an important component of the HEV. The performance of the battery will affect the capability and lifetime of the HEV directly. There are theoretical significance and practical value to do some research on the battery dynamic characteristic and test the work performance of the power battery in different environments, which will help us to make a reasonable application to the power battery, extend its lifetime and design better kinds of power batteries.The thesis introduces the performance parameters of the power battery, analyses the work principle of the MH-Ni power battery. It also introduces some battery characteristics such as the voltage, current, temperature and explains how it affects the capacity with different methods of charging and discharging. A method to evaluate the residual capacity of the battery is designed.The testing platform is built by different modules. The hardware of the system is divided into two modules, the data acquisition module and the control module. Based on single chip of MSP430, the data acquisition module can collect the voltage and temperature value and communicate with control module with CAN bus. The control module takes charge of collecting the sum value of the voltage and current, evaluating the remaining capacity of the battery and fault alarming. The control module collects all the batteries'information and then sends them to the PC.Based on the features of different control chips, different programs are designed by C language, which can collect the voltage, current and temperature. Digital filtering algorithms are adopted to improve the sampling accuracy. The progrom designed based on CAN bus achieves the communication between the control module and the data acquisition module. The error correction technologies are added to ensure the stability of the communication. Using the virtual instrument technology, a software interface is designed with LabVIEW, which has functions of saving and exporting datas of the batteries by files. It can help us to analyse the performance of the power battery.