Dynamic Characteristics Analysis Of Coaxial Sraight Axle For Pure Electric Minibus

Coaxial straight axle will integrate drive motor,deceleration mechanism and differential mechanism deeply,which can realize coaxial drive and output.It is mainly carrying pure electric mini bus and power transmission,supporting a pure electric mini bus load,bearing different impact load,and the load driving system to transfer as a variety of wheels.As a collection of various complicated force point,coaxial straight league axle directly affects the dynamic performance of pure electric mini bus overall NVH(Noise,Vibration and Harshness)performance.Therefore,the dynamic characteristic analysis has strong practical significance.This topic mainly comes from the major projects of Liaoning province science and technology innovation:pure electric drive axle of electromechanical coupling system,pure electric mini bus coaxial direct bridge is choosen as the research object,organically combining the finite element analysis method and test modal analysis technology,to analyze its dynamic characteristics.Applying of Solidworks coaxial straight axle parts 3d modeling,the coaxial direct axle strength calculation theory,the model is introduced into the ANSYS carrying on the simulation analysis on typical conditions and combination conditions to obtain the coaxial straight axle stress diagram and displacement nephogram.The results show that the coaxial straight axle design does not meet the standard requirements under the maximum lateral force.In the finite element modal analysis,selection of Block Lanczos method,output first six order natural frequency and vibration mode,and on the basis of the use of LMS test modal analysis,the result analysis of the data is more authentic,the modal analysis results show that the coaxial straight axle vibration did not occur mutation,and there is no resonance with the road surface excitation.Using ANSYS Workbench Fatigue Tool module for coaxial straight axle Fatigue life of the simulation analysis,nominal stress method and the S-N curve of material modification is selected to obtain the coaxial straight axle Fatigue life cloud.The results show that the coaxial straight axle Fatigue life is qualified.According to the above analysis results,the coaxial straight axle presents two improved methods,repeated simulation analysis of the model and the improved parameters.Improving design parameters,the paper determines the final structure model and carries on the simulation analysis to prove the rationality of the improved model.By the analysis of pure electric mini bus coaxial direct bridge dynamic characteristics,the above calculation results have the practical significance to engineer on their service life,reduce the cost and development cycle and improve the overall performance of pure electric mini bus.