Study On Simulating Of The Dynamic Driving System Of In-Wheel Driven Electronic Vehicle Based On The Electronic Differential System

With the development of global automobile industry,vehicle retention in the world increasing every year, which has brought two major challenges to the world:"energy depletion" and "environmental pollution."With the great advantages of Energy and environmental protection,Electric vehicles have become the hot research issue by every country of the world.As a new type of electric vehicle drive form,In-Wheel-driven electric vehicles have the following significant advantages:highly utilization of vehicle space,conveniently to import the technology of steering-by-wire to increasing the steering sensitivity,easily to achieve the functions of ABS|TCS|ESP by motor control,easily to reduce energy consumption by the regenerative braking power. It has become the direction of future development of electric vehicles.In this paper,the In-Wheel-driven electric vehicles driven by dual-rear-wheel are as the research object.Firstly,based on the dynamics analysis of electric vehicles when it is running straight and steering,the control strategy of the electronic differential system which is based on sliding rate is put forward.And the control structure scheme of Electronic Differential System of In-Wheel Driven Electronic Vehicle are established. Secondly,the parameters of Dynamic Driving System are matched and validated.Thirdly,the motor which is the key parts of the driving system of In-Wheel-driven electric vehicles are studied.This paper reviews a great number of domestic and international electric vehicle articles.According to the design requirements,the advantages and disadvantages of several motor for electric vehicle are compared and analyzed.And then,the energy saving and highly efficient brushless DC motor is selected as the drive motor.The battery of the design vehicle models use lead-acid battery,which is used on electric vehicles widely.Based on the kinetic analysis of vehicles,using the theory of vehicles and the knowledge of motor,the matching calculation of the peak power,the rated power, the rated voltage,speed and efficiency of motor are completed. The matching calculation of the battery voltage,power,battery SOC value and the internal resistance are completed.Based on the parameter matching result,using the simulation software ADVISOR,combining the theoretical calculations method and the software analysis method,this paper completes the validating of the parameters matching of dynamic System.In this paper,the models of the driving system of the brushless DC motor used by electric vehicle are established.And the operating characteristics of brushless DC motor and speed control principle are analyzed. To improve the performance of the driving system of the brushless DC motor used by electric vehicle,this paper adopts speed-current double closed loop feedback control scheme.To control the motor drive system,the speed loop using the classical PID control, and the current loop using current hysteresis controller.Based on the mathematical model of the driving system of the brushless DC motor used by electric vehicle and the motor control scheme,this article establishes the simulation model of the driving system of the brushless DC motor used by electric vehicle.The driving system is simulated by Matlab/Simulink and the results have good static and dynamic characteristics.Thus,the feasibility of the control method and control details of the brushless DC motor are demonstrated.And this study has some reference value to the research of the electric vehicles.