Analysis And Optimization Of Suspension Of Distributed.driving Electric Vehicle

Distribution driven for the vehicle chassis performance provides a broad space for improvement, but also is one of the most important development direction of modern electric vehicles. The industry attaches great attention to distribution driven,But there are also a series of weaknesses which need to be overcome in the distribution of wheel motor. The power transmission system from the body to the wheel, not only the existence of space round problems, and because the wheel motor is directly mounted on the wheel, increase the quality of automobile spring, the spring mass and in-spring mass ratio decreased, will cause the vehicle handling stability and ride down the influence of the driving behavior of the vehicle. Therefore,this article focuses on the negative impact of the hub motor, and through new suspension configuration and suspension parameters optimization matching to avoid the unsprung mass increase induced performance degradation, provide technical basis for distributed driving EV development.This paper establish distributed driving EV quarter dynamics model and vehicle dynamics model, different suspension configuration are considered in vehicle dynamics model test, and the introduction of the suspension guiding rod and a rubber bushing.Based on a quarter vehicle model and the simulation results show that increase the unsprung mass on vehicle ride and wheel dynamic load has a significant negative impact, not by changing the suspension stiffness, damping to eliminate negative effects.If the hub motor is suspended in the wheel, the function is equivalent to a dynamic vibration absorber, which can effectively overcome the negative effect caused by the increase in the quality of the spring.In this paper, the optimal stiffness and damping parameters of the suspension are optimized by the search pattern function, which makes the relative wheel of the suspension motor meet the restriction of the wheel arrangement space.The simulation results show that the wheel motor can significantly reduce the vertical acceleration, wheel relative dynamic load and suspension dynamic deflection of the body.Based on the simulation analysis of the whole vehicle dynamic model, the effectiveness of the suspension wheel motor to improve the ride comfort and handling stability is verified.When the hub motor as a dynamic vibration absorber and axle elastic connection, seat position vertical weighted acceleration value is reduced by 0.087 when the motor rigid connection, compared with a prototype vehicle is reduced by 0.017, compared with the rigid body connection,pitch angle is reduced by about 3.13 degrees, and compared with a prototype vehicle is increased by 0.54 degrees, the dynamic deflection of suspension compared with the rigid connection of motor axle suspension decreased slightly, compared with the prototype car deflection value changed little, the relatively dynamic load of the wheel motor compare with rigid connection, has been greatly reduced, compared with the original car, also slightly improved, that through the hub motor as a dynamic vibration absorber can improve the distribution of driving comfort and the safety of electric vehicles, the overall performance is even better than the prototype vehicle.