Research Of Battery Management System Based On Double Layer Equalization Technology

In order to solve the energy crisis and environmental pollution,people are seeking new energy and has made great efforts in reducing the waste of resources.With the continuous development of human society,the development of the power battery has also experienced its own unique path,from the initial lead-acid batteries,nickel cadmium battery,nickel metal hydride batteries and now lithium-ion batteries,the continuous development of each battery is accompanied by the progress of human society.Although the power of battery with humans for so many years but it is unable to overcome the shortcomings of each section of the power battery voltage and capacity that cannot meet the needs of people,so we need to pack the battery which can provide more energy for people to use.But in the process,the accumulation of different working environment and voltage imbalance undoubtedly exacerbate the battery monomer battery parameters are inconsistent.So we need to find a way to let the battery equalization in the practical application.This paper studied the lithium battery charging and discharging principle and the characteristics of the main work,introduce several representative equlization method,the calculation will Buck-Boost circuit combined with loose capacitance method to reach the dynamic equlization of monomer battery voltage between the battery pack in the first.This paper used a lithium battery series for the battery pack will be 12 monomer to experiment,and use GD32F103C8T6 as control chip for power management system.When the detection device found some parameters beyond the normal range,the control system will give alarm prompt,it will prompt alarm information told the vehicle controller through CAN bus communication,the vehicle controller will target specific failure problems to improve,so as to complete the control function of the battery management system.In this paper,the design of battery management system is divided into hardware system and software system,adopts the modular design idea.The hardware system includes control module,balancing module,voltage check section,the temperature check protion,the current check portion,alarm module,communication module,etc;The software system includes the master program,the voltage check program,the temperature detection program,the current check program,initial correction formality,fault alarm subroutine and sending and receiving subroutines,etc.The anti-interference measures is also used to ensure the battery management system well in the working process of the reliability and stability.In order to improve the ability to weaken the discharge of each single battery voltage,electric car lithium battery and shorten the service life of the inherent defects,this paper designs a bidirectional equalization scheme for nondestructive control circuit of power inductor based on the model,the scheme uses Buck-Boost to circuit the battery module balance.The simulation results show that the capacity efficiency C and energy efficiency E respectively from equilibrium before the 53.356% to the 59.582%,58.692%,67.463%,which can effectively play a balanced energy battery to prolong the service life of the lithium battery.Based on the broad prospects of lithium batteries in the field of new energy and practical application,use lithium batteries as the experimental battery,the power management system can realize the real-time monitoring of the state of the protection of the lithium battery,lithium battery is perfect.