Analysis Of The Shifting Process And Research On Controlling Methods For Automatic Manual Transmission

Automatic Manual Transmission(AMT)is added clutch actuator,shifting actuator and corresponding controlling units on the basis of traditional Manual Transmission(MT).Because of the advantages such as simple structure,low cost and power performance,AMT is increasingly used in hybrid vehicles,pure electric vehicles and other new energy vehicles.Thus,it comes to be the key technical issues to make AMT used widely by the way to shorten the time for power interruption and reduce the impact of the shift in the shifting process with the appropriate actuators and excellent control methods.This paper proceed the mainly research work in the following around the shifting process of AMT electric vehicle drive system.1.A detailed mathematical model for a new high-rigidity electronically controlled shifting actuator is established according to the working principle and the physical parameters.Subsequently,a dynamic model is established according to the dynamics analysis of the shifting process for the electric car AMT without shifting clutch,which includes stiffness,damping and backlash nonlinearity of gears and non-linear characteristic of synchronizer upshift process.2.In order to complete the shift smoothly,reduce shock and the time of the power interruption during the shifting process,improve shift quality as well,the sliding modecontrolleris designed for the position feedback of the synchronizer,based on the mathematical model of the shifting process.3.The speed control precision of the driving motor,value and rate of change of the shifting force and other factors on the shifting quality of electric vehicles AMT without clutch is analyzed,and the comprehensive evaluation index for shifting quality is proposed to improve the shifting quality of AMT without clutch.4.The reliability of the model is proved and the optimal shifting parameters are found by the contrast simulation of the shifting quality for different factors in shifting process of pure electric AMT,based on the shifting actuator model and the AMT shifting process model established by Matlab/Simulink and ADAMS software.Moreover,the contrast simulation results of the sliding modecontroller and the PID controller is given to prove that the new high-rigidity shifting actuator is technically feasible and the sliding modecontroller is stability in the shifting process in different gears.5.The results of simulation and bench test show that the shifting quality could be improved by the controlling of the shifting force,the rate of change of the shifting force and thevelocity accuracy of permanent magnet synchronous motor.In addition,the shifting quality is improved with the new electronically shifting actuator and the corresponding sliding mode controller whichhave the high stability,optimistic prospects for the development and large industrial potential at the same time.