Research Of The Compensated High-power Energy Storage Experiment Piatform

In recent years, li-ion batteries are widely used, and the balance of li-ion batteries in series is become a research hotspot of the battery management system. In this paper, there is a new battery equalization method on the common balancing method.First introduce the application background and prospects for the development of lit-ion batteries, and further informate the characteristics of the li-ion battery, the working principle and the charge-discharge characteristics and the charging method. Secondly, it analyzes the necessity and significance of the series li-ion battery balancing. And cites several commonly used cell balancing topology, its working principle as well as their advantages and disadvantages. In particular the improved bidirectional converter equalization method is explained in detail, including the topology and control strategy.This paper detailly analysed the charge and discharge process of balancing system of entire li-ion battery, given the power equalization system hardware design. It mainly consists of two parts:balancing circuit module and controller, balancing circuit module is mainly to complete the transfer of energy between the monomer battery and battery pack; and the controller complete to detect parameter of system, implement control strategy and output control signal.Balanced circuit’s forward working is voltage control, and reverse operation uses peak current control, the control structure is monocyclic. The main chip of controller uses TI’s DSP of TMS320LF240X series, sampling chip is LTC6802of Linear Technology, with SPI serial data transmission. Finally, design and build a compensated high-power energy storage experimental platform, and the experimental results show that:the equalization system is stable and meet the design requirements, have a significant improvement of the battery pack inconsistencies, played a balanced role.The paper mainly includes the finished work of the following sections:(1) In-depth research on li-ion battery:working principle and characteristics, the charge and discharge characteristics of the li-ion battery and charging method. SOC estimation methods of li-ion battery.(2) Elaborate the necessity of balancing of series li-ion battery, further informate the common equalization topology and strategic, and analysis of their advantages and disadvantages. On this basis, in this paper it designed a new equalization scheme. (3) Compensated high-power experimental platform is designed and built according to the equalization scheme. Including the design of balanced circuit, the design of the controller and the writing of the program.(4) Build storage experimental platform, it have seven of50Ah li-ion batteries.On the basis of the balancing experiment, analysed the experimental results, and summarized the experimental process.