Research On Matching And Optimization For The Parameters Of Small Pure Electric Vehicle Powertrain

The development of automobile industry has brought great pressure to the global environment and energy.In order to realize the sustainable development of automobile industry,the development of electric vehicle technology has been paid more and more attention.Electric vehicle has the characteristics of high efficiency and low pollution,which can alleviate the global environment and energy problems effectively.In the process of research and development of electric vehicle,we can improve the performance of the vehicle by reasonable matching,selection and optimization of the key parts.This paper is a study about Matching and Optimization for the Parameters of Small Pure Electric Vehicle Powertrain in the background of "small pure electric city vehicle development" project which is implemented by one domestic enterprise.The main research contents as follows:(1)In this paper,the background of the development of electric vehicles and the main related technologies are discussed firstly,then,the basic structure principle of pure electric vehicles is introduced,and determine its powertrain layout according to the Frequently-used layout of pure electric vehicles and the design requirements.On the basis of the market positioning and Parameters of competitor’s dumpers,its vehicle parameters and performance evaluation index is determined.(2)According to the vehicle parameters and the performance evaluation index,parameter matching of the main components of the pure electric vehicle,such as motor,battery and transmission has been done,combined with the types and characteristics of the relevant products on the market,determine the selection and speed ratio of power transmission system of the main components.(3)According to the related matched parameters of power transmission system,the simulation model of small pure electric vehicle has been established,the simulation of its power and economy is carried out,and optimize the speed ratio of the pure electric vehicle by using the interval optimization method combined with the vehicle performance evaluation system based on the weight coefficient.Before the optimization,the mileage does not meet the design requirements,the maximum speed,acceleration performance and mileage increased after the optimization,except the climbing performance declined,which meet the design performance requirements,improve the overall performance of vehicle.(4)According to the optimized vehicle parameters,sample car trial and related test verification has been carried out,due to the limitation of experimental conditions,the test project is the highest speed test,accelerated performance test and mileage test,by comparing the test results with the simulation results,verify the correctness of optimal matching of power transmission system and the rationality of simulation model established in Cruise.Under the background of actual product development,this paper has studied on parameters matching of small pure electric vehicle powertrain systematically,this research process can also be used for development of other models,and has certain directive to the development of pure electric vehicles.