The Research On Automatic Mechanical Transmission Shift Actuator Based On The Drive Of Dual-rotor Motor

Automatic mechanical transmission(AMT)is developed on the basis of the traditional manual transmission.It has the characteristics of high transmission efficiency,simple structure etc.In recent years,with the development of motor technology,dual rotor motor is gradually applied to various fields.The design and control of shift actuator are the key technologies of AMT,and its dynamic response directly affects the reliability of the vehicle starting and the whole system.A new scheme which it uses a dual rotor motor directly drives the shift actuator is proposed.It assembles the rotary and liner movement in an overall structure.The model has the advantages of compact structure and high transmission efficiency.In this paper,the key technologies of shift system are studied by theoretical analysis and simulation as the following:(1)Analyzing the stress characteristics in shifting process.Considering the requirements of the shift mechanism,we put forward two schemes.One of which is two motors respectively control selector and shift,the other is one composite motor directly drives the shifting mechanism.Through the comparison and analysis of the two schemes,the second scheme is adopted.The basic working principle of the model is that the rotary motion of the inner motor is changed into the linear movement of the shaft through a nut screw mechanism,and the external motor drives the shifting shaft to shift.(2)Based on the the maximum resistance of the shaft,the parametric design of the shift actuator is carried out and the strength analysis of the shaft is studied by the finite element software.The equivalent magnetic circuit method is used to analyze the electromagnetic relation of the motor.It is concluded that it can be regarded as two independent permanent magnet synchronous motors.(3)The vector control of the motor is determined based on the mathematical model.According to the requirements of the shift control system,the control strategy is put forward.Among them,when selecting,PID control is adopted in the current loop and velocity loop and position loop using sliding mode control for the inner motor;when the shift actuator turning,in order to ensure the synchronization of internal and external rotor.The methog of synchronous control is put forward which the outer motor is choosen as driving motor,and the other is driven.(4)According to the control strategy of the shift system,the control parameters of the setting system and the shifting system are analyzed.The gear shift system model is established based on Simulink software,and the results verify the practicability of the AMT shift actuator based on double rotor motor.