| Wheel-Independent-Drive Electric Vehicle is an important development direction in the field of electric vehicle’s technology.It has obvious advantages in vehicle dynamics control and driving force distribution due to the drive of independent motor.Furthermore,motor and battery technology provide a bright opportunity for the development of electric vehicles.In this study,according to the development model of control system for a Two-Wheel-Indcpcndcnt-Drive EV,the overall target is designed,the drive control strategy is designed,the software simulation is run,and the rapid control prototyping test is established.First,the overall design of a Two-Wheel-Independent-Drive EV is made.According to the design goal,the vehicle electronic control system is established,the driving system and power system are arranged,and the specific parameters of the motor and the battery pack are determined.Second,7 degrees-of-freedom vehicle dynamics model,the tire model,and linear two degree of dynamics model arc established according to the need of driving control.Electronic differential control strategy and driving coordinated control strategy are also designed.Electronic differential control is based on the steering model of the drive torque distribution,leading to low-speed smooth operation.The torque coordination control is based on the fuzzy control theory,where the yaw rate deviation and the sideslips angle deviation arc used as the input of the fuzzy controller,the additional yaw moment required as the output of the vehicle,which is reasonably assigned to each drive wheel.When the slip rate is higher than the threshold,the slip control is implemented to ensure the smooth operation of vehicles.Then,the vehicle model,motor model and control system model were established based on Carsim and Simulink,and the Carsim-Simulink simulation platform was built.The simulation results show that the proposed control system can effectively improve the driving stability of the vehicle under the angular step and the shift condition.The results show that the proposed method can improve the stability of the vehicle.Finally,a rapid prototyping platform based on dSPACE is built and verified experimentally.Experiment and simulation results of the comparative analysis show the effectiveness of the designed control strategy. |
