The Control Strategic Research Of Inter Axle Torque Distribution And The Development Of Controller For Electric 4WD Vehicle

In order to alleviate the demand of petroleum resources,reduce the automobile pollution to the environment,more people start to consider and accept the pure electric vehicles.In the study of dynamic allocation,four wheel drive technology has been more and more popular with people.On the basis of fully research of 4WD technology both at home and abroad,this article analyze the electric car transfer characteristics through transfer test platform,get the common types of transfer distribution features,and carry out dynamic performance test under different working conditions on the test bench,get the related performance parameters.Based on the research of characteristics of transfer,this paper set the studies scheme of the intelligent inter axle torque distribution control system of electric all-wheel-drive car.According to the analysis of the transfer characteristic test data,this paper settle the vehicle dynamics model,including electronic transfer model,transmission system model and tire model.Adopts intelligent PID control strategy based on fuzzy control to the key components of the power distribution transfer,and use the MATLAB/Simulink software to write the intelligent PID controller model,conduct the dynamic model simulation and analyze the effectiveness of the proposed control strategy.Use STMicroelectronics' s STM32F103 chip as the controller,make the hardware design of intelligent inter axle torque distribution controller of 4WD vehicle,introduce the minimum system controller circuit,power circuit,reset circuit and JTAG download circuit and transfer the electromagnetic clutch drive circuit,signal input processing circuit,signal output control circuit and CAN bus communication circuit design method,and briefly introduce the anti-jamming design and reliability requirements of hardware system at the time of the PCB design.Software design is in the development environment of Keil,the control system including library function call,initialization of system resources,signal acquisition and processing,control logic,PWM output driver,CAN bus communication are designed.By given part of the program flow diagram,clearly introduce the whole program.The vehicle experiment,first use testing instruments such as multimeter to make hardware test of will design controller,and make software test through online debug and simulation control debug.Place the good-debugged intelligent torque controller onto the group developed electronic intelligent all-wheel-drive vehicle,using NI company test instrument,through Labview software built the intelligent inter axle torque distribution controller test experiment data acquisition system,collect and analyze the test car's body data within and without transfer control under various driving conditions,conclude that with the control of intelligent torque controller designed in this paper,the passing ability and dynamic property of car has been obviously improved,proved that the design of the intelligent torque controller can effectively realize the four-wheel drive vehicle dynamic allocation.