Research On Structure Design And Shift Control Of Two-speed AMT Based On New Dog-tooth Clutch Of Pure Electric Vehicle

Compared with a single-speed pure electric vehicle,a pure electric vehicle with a two-speed AMT has been greatly improved in power and economy.However,the traditional two-speed AMT has many problems,such as poor shift smoothness,long shift time and so on.And after the clutch is cancelled in the power transmission system of pure electric vehicles,the moment of inertia generated by the output shaft of the driving motor will accelerate the wear and damage of the transmission.Therefore,it is important to design a new two-speed AMT which is suitable for pure electric vehicles.The main contents of this paper are as follows:1)A two-speed AMT based on a new dog-tooth clutch is designed.The three-dimensional modeling of the two-speed AMT is carried out in CATIA,and its virtual prototype model is established in ADAMS.The shifting process of the new two-speed AMT is divided into stages,and the dynamics of each stage is analyzed;2)The parameters of the pure electric vehicle with the new two-speed AMT and vehicle powertrain system are matched to ensure that the vehicle has a good dynamic and economic performance.The model of the pure electric vehicle and vehicle powertrain system is established in Matlab / Simulink;3)The shifting process of the new two-speed AMT is studied to ensure that the whole vehicle has good shift quality,and the control model of the new two-speed AMT is established in Matlab / Simulink;4)Joint simulation method of ADAMS and MATLAB is adopted,in order to simulate and analyze the shifting quality of the new two-speed AMT.The simulation results are compared with related datas of a traditional two-speed AMT,so as to get a conclusion that a pure electric vehicle with the new two-speed AMT has a better shift quality;5)Four factors that affect the shifting process of the new two-speed AMT are simulated and analyzed,including speed difference,vehicle speed,coil spring stiffness and transmission shifting force.The influence of four factors on the process of speed synchronous shifting is summarized,and the optimal speed difference?coil spring stiffness and transmission shifting force are given.