Modeling And Simulation Of Lithium Iron Phosphate Battery And Balanced Policy Verification

With the advantages of low pollution,low noise,convenient maintenance,pure electric vehicles tend to occupy the cars market in the future,as the auto industry develops.And because of the wide platform area which is based on the external characteristics,the lithium Fe phosphate(LFP)battery is gradually chosen to be used as power battery of the electric vehicles.However,the inconsistency of the battery becomes the main constraint for the development of the electric vehicles.Therefore,the research on the battery equalization is of great significance.At first,in this thesis,the performance test of LFP battery is experimented which leads to get the performance data.And the models of the single LFP battery and the whole battery pack,being constructed on the basis of the performance data,increase immensely and generally the artificial speed by introducing creatively the virtual battery.What’s more,by the research on the comparison between the system simulation experiments,the reliability and the accuracy have been proved.Next,the equalization circuit of the LFP battery is designed as well as the relative circuit model is constructed.And after the simulation verification by “simulink”,it is proved that the balanced current of the equalization circuit can be adjustable.After that,by using one-way series,one-say parallel and series-parallel hybrid structure,the circuit is respectively validated three times.Then,taking the equalization circuit designed as research object,multiple equalization strategies which include “without equalization strategies”,“compare to each other”,“predict equalization strategy”,“interrupt function joined strategy” and so on,are used to compare the experiments.Having analyzed every strategy and improved its disadvantages,the objective of the battery equalization is well realized at last.Finally,we draw out the corresponding schematic diagram and wiring diagram of equalization circuit designed by using the software PCB and we make them out.After the experiment of the modeling and simulation by the hardware circuit,we verify finally the accuracy of the modeling and simulation and the reliability of equalization circuit.