| Magnetorheological fluid(MRF)is a new type of intelligent material,in which magnetic particles can be closely aligned with the distribution of magnetic force lines to form a solid like substance.Based on this rheological property of MRF,researchers have developed a MRF damper with a damping force that can vary with current.Common magnetorheological dampers have the problems of low output damping force and requiring additional energy input to work.In order to improve the performance of vehicle suspension magnetorheological dampers,this paper proposes an electromagnetic energy fed stepped magnetorheological damper structure based on the design parameters of a domestic vehicle chassis suspension front damper.Through the reasonable design of the energy fed structure and the magnetorheological damper structure,The permanent magnet array is integrated on the piston head and the damping channel is designed as a stepped type.The electromagnetic energy feedback type stepped magnetorheological damper not only has the characteristics of small size and large output damping force,but also can store the electrical energy generated by the energy feedback device for use in the magnetorheological damper structure,which can not only save energy and protect the environment,but also improve the working performance and reliability of the magnetorheological damper device.The main work of this article is as follows:By analyzing the advantages and disadvantages of electromagnetic energy fed magnetorheological dampers in different operating modes,and combining the application background and design requirements,the magnetorheological damper of linear generator type stepped flow channel is selected as the design scheme of this paper,then the material selection,size determination and magnetic circuit design are carried out,and the modeling of energy management circuit and control strategy of the damper is described.1、The road excitation model of filtered white noise,the dynamic model of vehicle quarter suspension and the mechanical model of magnetorheological damper are established respectively,combining with the control strategy modeling,the vehicle magnetorheological semi-active suspension is simulated and analyzed,and the performance parameters of semi-active suspension and passive suspension under the random excitation input of road surface are compared.2、The static magnetic field simulation analysis method is used to analyze the magnetic circuit sensitivity of the energy feeding structure and the magnetorheological damper structure,and the magnetic isolation mechanism is improved to reduce the magnetic field interference between the two structures.The magnetic flux density distribution in the damping channel is simulated and analyzed to observe the influence of damping gap,coil slot position,current size and coil turns on the damping performance of electromagnetic energy fed stepped MR damper.The results show that the output of the electromagnetic energy fed stepped magnetorheological damping semi-active suspension based on fuzzy adaptive PID control is significantly better than that of the passive suspension in three parameters:suspension dynamic deflection,vehicle dynamic load,and vehicle acceleration.3、An electro-hydraulic servo damping suspension test system was used to test the energy feeding and damping characteristics of an electromagnetic energy fed stepped magnetorheological damper.The effectiveness of the structural theoretical design and simulation method is verified by experiments. |
