Research On The Key Technology Of Lithium Battery Simulator

With the rapid development of portable smart devices,lithium battery is applied more and more widely,especially in intelligent mobile phone and computer field.There have been more than a cell phone explosion spontaneous combustion accident in 2016 in China,the main reason is that the production and use of lithium battery is not standardized.So the safety of lithium battery is gradually putting on the agenda.In order to ensure the safe use of lithium batteries,the necessary testing is particularly important.Typically,the lithium battery testing procedures are cumbersome,and it needs longer the testing time and requires more testing equipment.The emergence of Lithium battery simulator can solve this problem.After understanding the current situation and development trend of lithium battery simulator at home and abroad,this thesis analyzes the simulation scheme of lithium battery given by well-known university researchers,combined with the design requirements,and puts forward a unique design scheme of lithium battery simulator.In this thesis,the technology parameters and models of lithium battery are analyzed in detail.In order to realize the battery charge and discharge characteristics,a power amplifier type push-pull linear circuit structure scheme is proposed,the feasibility and the design basis of the scheme are introduced in detail.The circuit design parts mainly include the main circuit,the constant voltage and constant current control circuit,the sampling circuit,the power amplifier circuit and the transient enhancement circuit.The device types and sizes of the main circuit of the regulator tube,power amplifier driver chip,sampling circuit operational amplifier,error amplifier,voltage regulator chip,rectifier bridge,capacitors,resistors and other devices are completed.The correctness of the circuit designs are verified by the LTspice software,which are constant voltage control output circuit,constant current control output circuit,and the switching between them,charging constant current control output circuit.The stability of the constant voltage control output main circuit is analyzed in detail,the simulation results of the simulation before and after the proportion integration differentiation(PID)control are compared and analyzed.A transient enhancement circuit for lithium battery simulator is proposed.The physical production and experimental results analysis are completed finally.The experimental results show that the indexes of lithium battery simulator,which is designed,achieve the desired target.Lithium battery simulator achieves the charging function,the discharging output of 0-5V adjustable voltage,the discharging output of 0-3A adjustable current value,rise time and fall time of the voltage are less than 50 microseconds.The lithium battery simulator meets the test requirements of lithium battery.