Mode Switching And Control Strategy Of Dual Motor Coupled Driving On Electric Vehicle

With the continuous development of pure electric vehicles,dual motors coupled driving system provides a new solution,as a new type multi-power drive systems,which provide a new solution for solving the dynamic and stability of the electric vehicle.In this system,Two motors are respectively connected with the sun gear and the ring gear in the planetary coupling device as the input end of the vehicle,and the planet carrier is connected to the vehicle main reducer or directly connected to the vehicle as the output terminal of the vehicle.To meet the requirements of low speed and high torque,high speed and high power,making the motor drive and planetary coupling device togetherThis paper makes the pure electric vehicle that using double motor planetary coupling drive system as the power source as object,and analyzes a variety of work patterns,mode switching method and control strategies in working process.The mechanical structure,basic composition and working principle are analyzed according to the dual motor planet coupling drive system adopted in the project,and the relationship between the rotational speed and torque of the motor and planetary coupling device is analyzed by using the equivalent lever method.Meanwhile,the working state of the driving motor and the brake is analyzed,which provide the basis for research on the dual motor coupling driving mode switching.A mode switching law is designed based on the vehicle speed as the switching condition,combined with the control of the vehicle to supplement the switch from the single motor-drive to the dual motor coupling drive.It is necessary to improve the precise control of the drive motor-drive system to get more accurate vehicle speeds.Present commonly used multi-motor controller with PID control.A combined with QPSO group fractional order of the fractional order PID theory’s PID controller based on the quantum particle swarm optimization algorithm is designed.The parameters of the controller,Kp,Ki,Kd,are optimized through the QPSO algorithm,to obtain optimal values of control it.And the use of Matlab/Simulink to verify that the performance of using fractional order PID controller to motor-drive speed control response speed is faster and better anti-interference ability than the traditional one.In order to verify the designed multiple operating mode switching law,based on Matlab/Simulink software simulation,the simulation model of the planetary coupling drive system of the pure electric vehicle is set up.Several driving conditions of the pedal are designed by the driver,and the working condition of the motor and the working condition of the brake is analyzed and verified.At the same time,the speed of the drive motor when it switches between the single and double motor driving modes.The results demonstrate that the switching between the sole motor-drive mode and the dual motor coupling drive mode can be realized,and the vehicle has no power interruption during the switching process.Finally,AMT automatic transmission of pure electric vehicles was compared and analyzed,and verified by double motor planetary coupling drove by pure electric vehicles than the pure electric vehicle AMT automatic transmission can achieve high speed more quickly.