Integrated Design And Experimental Study Of Torsion Beam Drive Anle For Electric Vehicle

In recent years,under the guidance of the new national energy policy,automobile manufacturers have been increasing the research and development of electric vehicles,making electric vehicles become a research hotspot.With the enhancement of consumers' awareness of energy conservation and environmental protection,electric vehicles are favored and their market share is increasing constantly.After the electric vehicle is put into the market,the quality problem is tested,especially the drive axle problem.Firstly,the drive axle is bulky and not suitable for electric vehicles.Secondly,the design difficulty is higher because of more transmission mechanism and drive axle housing design is more complex.Finally,the drive axle of low weight is difficult to meet the national standard in strength and stiffness.This paper proposes a solution of torsion beam drive axle for electric vehicle aiming at the quality problem of drive axle in use.Firstly,according to the performance target of electric vehicle,the geometric structure and performance parameters of transmission mechanism are designed and calculated.Secondly,with the help of computer simulation software,the drive axle is simulated and optimized through the structural stiffness fatigue analysis.Finally,a physical prototype was developed and tested The main research contents are as follows:1?Based on the investigation of the transmission mode of electric vehicles,an optimal transmission mode is selected and a new torsion beam drive axle is proposed.Combined with the basic parameters of an automobile,the structure design and parameter calculation of the drive mechanism and drive motor of the new torsion beam drive axle are carried out in detail.Based on the design and the results of calculation,the three-dimensional geometric model of torsion beam drive axle is established by using CAD software.2?Finite element analysis of stiffness strength of torsion beam drive axle.Based on the geometric model established above,the stiffness strength finite element analysis model of torsion beam drive axle is established with CAE software.In this paper,the finite element analysis of the axle housing of torsion beam drive axle is implemented under five limit conditions commonly used in the driving process of automobiles,and the results of rigid strength analysis are evaluated according to the strength theory and the national standard.3?Fatigue analysis and modal analysis of torsion beam drive axle.The fatigue life analysis method of torsion beam drive axle is expounded,the S-N curve of corresponding material is modified,and the fatigue life simulation analysis of drive axle is carried out,and the distribution rule of fatigue life and safety coefficient of drive axle housing is obtained.Modal analysis of torsion beam drive axle is carried out,and the first 6 order natural modal frequency of drive axle is obtained,and first 6 order natural modal frequencies are compared with pavement excitation frequency.The designed torsion beam drive axle meets the design requirements in terms of fatigue life,safety coefficient and NVH.4?Optimization and verification of torsion beam drive axle structure.According to the analysis of the stiffness,fatigue and modal of torsion beam drive axle,the optimization scheme is developed.Based on the working condition when the maximum displacement variation of the drive axle is taken as the background,the position with the maximum stress is analyzed.The length of the position is taken as the optimized input variable,and the strength and stiffness meeting the national standard are taken as the optimized output standard for optimization.At last,the optimization results of torsion beam drive axle are simulated and verified,and evaluation indexes were improved compared with those before optimization.