Damping Optimization And Integrated Design Of Energy Saving Electromagnetic Active Suspension

Suspension,as the major components to attenuate the vibration from road to vehicles body,has an important influence on vehicle dynamic performances.Because the active suspension can output the optimal active force in real time according to the driving condition of the vehicle,which greatly improves the ride comfort and driving safety of the car,and has high application value,however,active suspensions are limited in the real vehicle applications due to the defect of great energy consumption.Therefore,how to effectively balance the energy consumption and dynamic performance of active suspension is the key problem to be solved.Consequently,the energy consumption problem of active suspension is taken as the breakthrough point in this paper,and a kind of energy-saving electromagnetic active suspension structure is put forward,meanwhile,the key methods and technologies to reduce the energy consumption is studied,then the research results and real vehicle applications are combined to design the integrated electromagnetic actuator structure to realize the goal of automotive design,which is "energy saving,miniaturization,lightweight".The main contents of this paper include:First of all,the traditional hydraulic shock absorber is introduced into the electromagnetic active suspension,and the energy-saving active suspension structure of the spring-damper-linear motor in parallel is constructed.This structure can not only improve problem of the traditional active suspension of low reliability,but also provide a new way to reduce the energy consumption of electromagnetic active suspension.Then,the mathematical model of 1/4 energy-saving electromagnetic active suspension is built,and its inherent characteristics and frequency domain response characteristics are explored.The road disturbance model is established for three common conditions(freeways,urban highways,rural highways).On the basis of the above mathematical model,the state space model of the active electromagnetic active suspension is established,and the linear quadratic optimal controller is designed,as well as the overall control strategy of the suspension is determined.Secondly,the weighted coefficients of the optimal controller are determined by the analytic hierarchy process,hydraulic damping values(ie,the passive damping values connected in parallel in the energy-saving electromagnetic active suspension)influence on vehicle ride comfort and driving safety and energy consumption is studied,finally,the optimal passive damping value is designed to effectively coordinate the vehicle dynamic performance and energy consumption characteristics.The results show that the energy-saving electromagnetic active suspension with appropriate parallel damping can effectively coordinate the energy consumption and vibration isolation of the suspension,and due to the addition of passive damping,the active control of the suspension is significantly reduced,which means that you can use those low-cost,smaller models of the linear motor as the main suspension of the output device.At last the three optimal passive damping values are set as the three adjustable damping coefficients of the hydraulic shock absorber in the energy-saving electromagnetic active suspension to achieve its wide application of various working conditions.Thirdly,the equivalent active test bench is used to compare and validate the theoretical design of the optimal passive damping with traditional electromagnetic active suspension and electromagnetic active suspension with general passive damping in parallel.The results show that the experimental results are consistent with the simulation results,which verify the validity of the control system and the effectiveness of the energy saving electromagnetic active suspension structure.Finally,the integrated design of the linear motor and the adjustable shock absorber is carried out by taking the assembly space of the real vehicle as the constraint target.The finite element analysis method is used to analyze the performance of the linear motor with different structures.The results show that the motor structure with slotless stator and permanent magnet of axial arrangement has larger air gap magnetic field density and smaller thrust fluctuation.On the basis of this,the overall structure of the integrated electromagnetic actuator is drawn,and the material selection of the key components is determined.Based on the combination of lumped magnetic circuit model and finite element model,the structure of the linear motor is determined,and the design of the whole actuator is completed,which lays the foundation for the production of the subsequent solid prototype.