Li-ion Battery Management System Design And Energy Equalizer Research

As an electric vehicle that can effectively reduce air pollution and ease the dependence on petroleum,electric vehicles have now become a research hotspot in the automotive industry.As one of the key technologies in electric vehicles,the battery management system(BMS)plays an important role in promoting the development of electric vehicles.The main work of the graduation thesis is to propose a new lithium-ion battery energy equalizer and design a battery management system.After analyzing and comparing various common equalizer circuit topologies and equalization strategies,the author proposes a new balanced circuit topology and equalization strategy.The newly proposed equalizer is based on the Sepic and Zeta chopper circuits and is a non-power-conserving equalization method.It can achieve bidirectional transfer of balanced energy,and the balance current can be controlled.Using MATLAB software to simulate the new equalizer,the newly proposed equalizer can effectively increase the battery pack charge capacity and discharge capacity.After the battery pack is charged and discharged through multiple cycles,the energy difference between the individual cells is significantly reduced,explain that the new proposed equalizer can achieve a good balance effect.The battery management system design includes hardware circuit design and program block diagram design.The hardware design is to design the hardware circuit of each functional module of the battery management system,including: the design of the main control circuit,auxiliary power circuit design,isolation circuit design,the design of the cell voltage acquisition circuit,the design of the temperature acquisition circuit,the design of the total voltage and battery pack charge and discharge current acquisition circuit design,fault management circuit design,balance circuit design and communication circuit design.The program block diagram design is to design corresponding software program for each module of the hardware circuit,in order to realize the function of the hardware circuit.