Research On Vibration Control Of Electric Wheel Vehicle Based On Semi-Active Suspension

The electric wheel drive vehicle which is also called the hub motor drive vehicle has many advantages compared with the conventional centralized drive vehicle,such as reducing the transmission mechanism components,improving the transmission efficiency,simplifying the chassis structure,increasing the utilization ratio of the interior space,but The built-in drive motor,brake mechanism,reducer and other structures of the wheel greatly increase the unsprung mass,which is not conducive to vehicle ride comfort and handling stability.The role of the vehicle suspension is not only to cushion the vibration and impact from the wheel to the body,but also to ensure the grounding of the wheel,so that the driving force or braking force is generated between the wheel and the ground,so the suspension needs to improve the ride comfort.It is also necessary to ensure the steering stability of the vehicle.Conventional passive suspension applications can perform well on centralized drive vehicles,but their application is often stretched on electric wheel drive vehicles,due to the increased quality of the unsprung and the impact on the hub motor as much as possible.Electric wheel drive vehicles place higher demands on the suspension.In this paper,the semiactive suspension based on magnetorheological damper is used to actively control the vibration of electric wheel drive vehicles.The main contents of the research include:(1)Establish a passive suspension model and a semi-active suspension model for a two-degree-of-freedom 1/4 electric wheel drive vehicle,and establish a mathematical model of road roughness.(2)Based on the magnetorheological damper to build the test rig,the parameters of the established magnetorheological damper parameter model are identified based on the experimental data,and the magnetorheological damper model selected in this paper is obtained.In addition,based on the established magnetorheological damper model,the damper inverse model is obtained.(3)Design the control strategy of magnetorheological semi-active suspension.Two hybrid algorithms are used in this paper,namely PID controller based on BP neural network and LQG controller based on genetic algorithm multi-objective optimization.Based on the designed control strategy and the mathematical model of the magnetorheological semi-active suspension,the simulation model was built using MATLAB/Simulink software.(4)The off-line simulation verification of the semi-active suspension model and the traditional passive suspension model under the control of two algorithms are carried out respectively.The model outputs the vertical acceleration of the vehicle body,the dynamic deflection of the suspension,the dynamic load of the wheel and the impact of the motor.Four evaluation indicators were used to analyze and compare the results,and verify the effect of the two strategies on the magnetorheological semi-active suspension.In addition,the dSPACE online real-time simulation platform is used to verify the model and algorithm.