Analysis And Optimization Of Power Battery Package Assembly Arrangement For Battey Electric Vehicle

Electric vehicle is becoming a new direct ion of the automot ive industry wit h low emission, high utilizat ion rate of energy, low noise, wide energy sources. However, considering the development costs of reason, the development of the electric vehicle is st ill based on the original tradit ional vehicle to be retrofitted by electrificat ion. But battery energy is far less than the traditional fuel so that the weight of battery package is accounted for a large proportion of the whole vehicle. Compared to the traditional vehicle the electric car has generally bad handling stabilit y and ride comfort. Therefore, research work on dynamic performance and the chassis’ s st iffness of electric vehicle can not be ignored.In this thesis, the handling and stabilit y and the chassis dynamic st iffness of a battery electric vehicle is studied, which was retrofitted by electrificat ion from a tradit ional car by project group. According to the performance requirements of electric vehicle, a chassis layout scheme is given. A mult i-body dynamics model of rigid elastic coupling is established based on mult i body dynamics theory and ADAMS/CAR. The finite element model of trailing arm and torsion beam rear suspensio n are set up based on Hyper Mesh. And the free modal analysis is given. Trailing arm and torsion beam flexible body MNF neutral file is generated. Then a model of torsion beam suspension dynamics of rigid flexible coupling is sdudied. Then, other rigid subsystems are also established. Based on the electric version of the vehicle model, in accordance with nat ional standards, the steering wheel angle step input, steering wheel angle pulse, steady state circular test, snake test are performed and contrast analysis is carried out, evaluated by score. The structure factors on the impact of vehicle hand ling and stabilit y are analyzed, including the location of center of mass, load. Based on the performance of the handling and stabilit y, the posit ion of the battery package is opt imized wit h ADAMS/Insight.Finally, according to the layout of the battery, the effect of battery package on dynamic rigidit y of the frame is researched considering with the battery box as flexible body. The changes of chassis frame’s modal before and after modificat ion is analysed. And based on the chassis frame’ modal, the posit ion and numbers of the connect ions to battery package are optimized.