Research On Shift Control Of Clutchless AMT Of New Energy Logistics Vehicle

The increasingly severe environmental pollution problem and the rapid development of the logistics industry promote the promotion of new energy logistics vehicles,and new energy logistics vehicles are gradually developing towards the trend of integration.In the existing centralized drive system of new energy logistics vehicles,the traditional single-stage transmission has higher requirements for motor matching and performance,while the multi-shift non-clutch mechanical automatic transmission(AMT)can reduce the burden of the motor and reduce the cost to meet the requirements of power performance and economy,but there is still the problem of power interruption.Therefore,in order to improve the shift performance and shorten the shift time,this paper takes the clutchless AMT of new energy logistics vehicles as the research object and proposes a coordinated shift control scheme.The main work contents are as follows:(1)The relevant mathematical models of drive motor,shift motor,actuator,transmission system and transmission in the motor transmission integrated system are established.Based on the movement of synchronizer sleeve in the process of shifting,the whole shifting stage is divided into six stages: unloading,shifting,active synchronization,mechanical synchronization,shifting and torque recovery.The working mode change of driving motor in each stage,the change of speed and position of synchronizer components(lock ring,engagement ring gear,coupling sleeve,etc.)are described in detail.The multi-body dynamics of the model is analyzed.(2)This paper introduces the shift control strategy of the coordinated control of the motor transmission integrated system,which controls the speed synchronization of the drive motor,the shift force of the coupling sleeve and the position at different stages.The robust preview controller is designed according to the position of the coupling sleeve.The control gains of preview control,feedback control and integral control are obtained by using Matlab / LMI toolbox.(3)The whole shift model is established based on MATLAB / Simulink and AMESim.The transmission control unit module,motor control unit module and transmission system module are established in Simulink,and the synchronizer and vehicle models are established in AMESim.Through the interaction of torque and shift force signals,the shift process is co simulated.The results indicate that the proposed coordinated control method is effective in reducing the shift time and optimizing the shift performance.The influence trend of the controller design parameters on the control effect of the sleeve position is analyzed.