Dynamics Characteristics Simulation Of In-Wheel Motor Electrical Vehicle

The development of the automobile has changed people’s life. The automobiles have become an essential vehicle for most people, which comes along the growing disruptions of energy environment, yet. At present, China has become the world’s largest energy consuming country. With the aggravation of air pollution problems and global energy shortage, the development of new energy vehicles is an irresistible trend, no matter from the level or growing demands of energy, or in view of the energy structure and carbon-reduction targets. Wheel drive electric vehicle have attracted much attention because of its simple mechanical structure, light weight, and efficient transmission systems. It becomes an important direction in the development of electric vehicles in the future. In this paper, the dynamics characteristics simulation of in-wheel motor electrical vehicle was studied.(1) In this paper, we establish mathematical modes of permanent magnet synchronous motor, after that turn them into two phase rotating coordinate system by decoupling. According to the vector control principles of motor take the complex of motor into simplify model. Then the simulation model of permanent magnet synchronous motor is built with MATLAB/Simulink by using double closed loop control scheme. The results show that the model can fully reflect the motor’s speed and torque characteristics.(2) The paper established 1/4 vehicle machine-electrical coupled dynamic model of the in-wheel motor electric vehicle, combined with the model of motor torque fluctuation and random road. To explore the vertical machine-electrical coupled vibration characteristic of in-wheel motor electric vehicle, the vibration analysis was executed using the simulation model programmed in MATLAB/Simulink. The results show that all the performance parameters of suspension system are affected by the motor torque fluctuation, when the motor quality is 20kg, motor speed is 955r/min and output electromagnetic torque is 100Nm, especially the wheel as unsprung mass. All these deteriorate the tyre grip, reduce the safety of vehicle driving. The research can provide analytical theory and methods of industrial development, and an exploratory program to improve the integrate NVH performance study for in-wheel motor electric vehicle.(3) According to the basic principle of vehicle system dynamics, establish the dynamic simulation model of in-wheel motor electrical vehicle by MATLAB/Simulink software. The model included fourteen degrees of freedom: six degrees of freedom of the vehicle body, eight degrees of freedom of the vertical jump and the rotation of the four wheels. Simulation analyses are carried out on the 14 degrees of freedom vehicle dynamics mode, first of all, in the steering wheel angle step input, simulation curves with two degrees of freedom of the ideal state of simulation curves are compared to validate the built model of rationality; Second, we analyze the handling stability of the whole vehicle model by simulating two kinds of typical working conditions with steering wheel sine wave input and triangle wave input. The simulation results show that the handing stability simulation of the built whole vehicle model is consistent with the actual, and this model can be used for vehicle handling and stability performance.