Coordinated Control Technology For AMT Of Pure Electric Vehicles

In order to improve the performance of electric vehicle(EV),making full use of electrical characteristics,the structure drive motor+AMT are widly used now.In this paper,the basic parameters of the pure electric vehicle(EV)powertrain are obtained by matching and calculating based on the basic demand of power performance and fuel economy about vehicle.In view of the research status of EV powertrain,this paper focused on integrated design of PMSM and AMT without clutch,and the process of T-MCU(Transmission-Motor Control Unit)for no-clutch PMSM-AMT coordinated controls drive motor and no-clutch AMT to complete shifting.This paper take the shifting quality as the evaluation index to establish the coordinated shift control strategy.Finally complete the pure electric vehicle simulation process from starting to accelerating to shifting,and verify the coordinated shift control strategy.The main works are as follows:(1)The development status of pure electric vehicle are briefly introduced,research and desigened the form of transmission of integrate drive motor and automatic transmissionare so sa to save the vehicle space and improve the performance of vehicle.Combined with the characteristics of the motor,the no clutch AMT shift scheme is proposed,and the feasibility of the AMT gearshift is proved by physical process analysis.(2)The application status of pure electric vehicle drive motor are summarized and compared,take permanent magnet synchronous motorthis(PMSM)as drive motor.And aimed at the requirements of the parameters of the target vehicle and the basic performance,calculated the drive motor's power and speed,the AMT gear and speed ratio and the speed ratio of retarder and other parameters.Finally choose PMSM and two-speed AMT as powertrain form.(3)The system of PMSM-AMT and the vehicle dynamics are analyzed during the driving process,and established the simulink model of drive motor model,no clutch AMT model and vehicle model.(4)This paper analyzed the control principle of PMSM from starting till accelerated to shift.Focuseed on the flat road vehicle starting process control and the shift coordination process control of PMSM-AMT system.Taking start quality as the evaluation index and establish start drive motor control strategy,moreover integrate PMSM-AMT system controller,and shift process into ready to pick out,pick out,synchronization,put on gear,restore power five stages,take shift quality as evaluation index,analysis the influence factors of each phase,formulate corresponding drive motor coordination AMT shift process control strategy.(5)Analysis of permanent magnet synchronous motor control principle,the research status of the permanent magnet synchronous motor control method,combined with the demand of driving process of pure electric car for controlling the motor,driven by the new SVM-DTC PMSM control method,guarantee the stability of drive motor dynamic control process,and improve the drive motor control precision and dynamic response.(6)On the foundation of the driver's starting demand,the control strategy of pure electric vehicle was simulated at 20%,40%,60%and 80%throttle angle respectively.At the same time,simulated the process of starting and accelerating to shift gear at 40%throttle angle,and verified control strategy of coordination control of the drive motor and AMT shift process.The simulation results show that the design of PMSN-AMT system is feasible and shift coordination control strategy improved comfort and efficiency of shifting gear at a certain extent.