Research On Actuator System For AMT Electric Shifting

Automatic mechanical transmission can realize automatic gear shifting and combines the advantages of the traditional manual transmission such as high mechanical efficiency,simple constructure,and low manufacture cost,making it play an very important role in automatic transmission products.The electric shifting actuator system is an important part of automated mechanical transmission.Its performance directly determines the performance of the transmission,thereby affecting the dynamic characteristics and comfort of the vehicle.Therefore,the research on actuator system for AMT electric shifting has important engineering practical value.The main works and fruits of the thesis are as follows:Firstly,the theoretical analysis of shifting process.The shift process was analyzed so that the force of the actuator in the gear shifting process can be clearly defined.Mathematical model were established based on the analysis of self-locking resistance and synchronizing force In the shift process.The evaluation index of shifting quality is introduced,and the relationship between the three evaluation indexes is analyzed.Secondly,the analysis of electric shift actuator is carried out.The working principle of the electric shift actuator is analyzed and its working process is defined.By analyzing the two structural forms and various transmission modes of the electric shift actuator,the orthogonal structure,the ball screw drive and the gear transmission mode are adopted.According to the performance requirements of the actuator,and combined with the characteristics of each type of motor,the type of the shift motor is finally determined,so that the structure is reasonable,compact,easy to implement and lower cost;The specific parameters of the actuator and the scheme of the electric shift actuator are determined.Thirdly,the research on the electric shift control methods is carried out.The mathematical model is established based on the working principle of Brushless DC motor.Brushless DC motor is controlled by pulse width modulation driving mode and PID control algorithm.The mathematical model is established based on the working principle of two phase hybrid motor.Bipolar driving mode and closed loop control mode are adopted.The control objective and control method of the shift motor are defined,and the accurate control of the motor is realized to meet the performance requirements of the shifting actuator system.Finally,the real time simulation test of electric shift system.The model of the gearshift motor is built based on Matlab/Simulink is build so as to verify the feasibility of the control algorithm.Further,the electric shifting actuator system model is built,and the whole system is simulated offline in order to verify the feasibility of the system.The real-time simulation model is established based on d SPACE,and the real-time simulation test under different shift conditions is completed.The results of real-time simulation test show that the control method is feasible.