Design And Implementation Of Charge And Discharge Equilibrium System For Power Battery Pack

In the respects of energy and environment,electric vehicles has been recognized fully by the public.And the battery that such is power source of electric vehicle plays a decisive role.Generally speaking,battery pack that mades by the multi-section power batteries in series provides energy for electric vehicle.Due to manufacturing and process defects,battery will be different even belongs to the same type.In addition,the power battery will conduct repeated charge and discharge cycle during the driving process and the process will cause the expansion of the battery inconsistency resulting in individual battery overcharging and overdischarge.It not only cuts the battery life,but also may cause serious accident.Therefore,it becomes the top priority of the current battery management to ensure the consistency of electric vehicle battery.This paper will do a series of research and analysis of above phenomenon.1.This paper expounds that the electric vehicle have made revolutionary change in the aspects of environmental and energy.By comparing the advantages and disadvantages of various vehicle batteries,the superiority of lithium battery in electric vehicle is confirmed.By analyzing the advantages and disadvantages of balanced topology and equilibrium strategy,this paper introduces the importance of non-energy-dissipation equalization technology.It not only improves the life and efficiency of battery pack,but also has great advantage in saving energy.2.By research of the battery inconsistency,this paper analyzes the working mechanism,the significant parameters of lithium battery and the intuitive reflect of these parameters of power battery.The charge and discharge characteristics of the lithium battery were analyzed and the HPPC experiments were carried out according to the PNGV battery model.The mechanism of the lithium battery inconsistency and the external parameters were analyzed by experiment and data.Finally,working voltage would be a balanced variable to reflect the inconsistency of the battery pack.3.According to the DC-DC transform topology,the non-energy-dissipative storage inductance symmetrical equilibrium topology is designed.By analyzing the working principle of the equalization circuit and designing the structural parameters,the circuit are simulated.In this topology,the design of the equalization strategy is put forward and the equalization strategy design under charging and discharging is proposed with simulation.4.On the platform of balanced circuit theory and simulation,this paper established the hardware and software system.The whole system is divided into detection part,equalization control part and balanced implementation part.The hardware adopts the modular structure design circuit and the processor achieve two different conditions of the equilibrium strategy in which the discharge balance simulate with docking equilibrium.5.Set up the experimental platform,match the experimental results and the corresponding requirements of the corresponding.The correctness of the non-energydissipative storage inductance symmetric equalization system is verified.