Design And Simulation Of Monitoring System For Lithium Battery On Wireless Technology

Battery management system is key factor that affects not only the performance of electrical vehicle (EV), but also development of EV. In the thesis, a new scheme of monitoring system for lithium battery on ZigBee wireless communications is presented to solve the main problems that the traditional wire communication is not greatly reliable with bad expansibility and current measure method about high voltage of secondary cell can't give attention to high precision and low cost simultaneously. The scheme is verified to be feasible through the hardware, the SABER simulation and software respectively. The primary achievements are in the following:In the thesis, firstly, ZigBee wireless communication technology and combining Ah arithmetic with PeuKert equation arithmetic to forecast state of charge (SOC) method on lithium battery are presented which are based on compare and analysis for the current forecast methods of the SOC, main wireless communication technologies and the capability parameter of secondary cells. The forecast method doesn't only decrease memory space for the simple arithmetic, but also adequately utilizes high precision's merit of Ah arithmetic, and takes into consideration temperature and current in EV travel process. At the same time, based on the ZigBee specification, the design about organization of network such as the network topology scheme and transmission principle is investigated and proposed.Secondly, the thesis compares and demonstrates the schemes of the principal structure, the control chip, the RF chip, ZigBee communication circuit, the measure circuit and power supply circuit etc. According to the technology requirement of the system, the selected schemes of the hardware circuit are confirmed and the design of the hardware circuit is completed. The differential amplifier design method of the high voltage measure to advance measure precise and decrease cost is investigated and developed by simulating and experimenting to demonstrate the performance of the proposed method.Finally, the software design and debugging are finished. Simultaneously, a series of correlative experiments are completed. The software design follows the pattern of modularization and the top-to-bottom design. In the thesis, the whole frame structure and the design of ZigBee communication procedure are mainly analyzed.