Modeling And Experimental Research On Energy-feedback Type Suspension System Of Electric Vehicle

With the development of the automobile industry and the increase of energy and environmental crisis,electric vehicles will become the trend of the automotive industry in the future.At the same time,people demand higher requirements for car ride comfort and handling stability.Suspension system as an important part of the car,its performance will have a vital impact on the car’s ride comfort and handling stability.Among them,the magneto-rheological semi-active suspension has become a hot spot in the automotive research field because of its advantages such as fast response speed and low energy consumption.However,traditional MR dampers have some problems such as failure safety and static settlement of MR fluids,which hinders the popularization of MR dampers to some extent.For this purpose,a permanent magnet ring is added to a conventional magnet-orheological damper,a new type of built-in permanent magnet ring magneto-rheological damper is designed,and a control algorithm with excellent control effect is designed for the semi-active suspension so as to improve the damping effect of the suspension system.At the same time,because electric vehicles have the problem of short driving range,how to save energy has become one of the hot topics in the research field of electric vehicles.Energy recovery as an important means of energy saving,energy-feedback type suspension was born.For this reason,this paper will design the energy-feedback device for the built-in permanent magnet ring type magnet-orheological damper,convert the energy of the vertical vibration of the car into electrical energy and store it in the battery pack for use by the drive system,and increase the driving range of the electric vehicle.The specific research content and related work are as follows:(1)Based on the structure of traditional MR damper,combined with the structure scheme of commonly used energy-feedback damper,the energy-feeding type built-in permanent magnet ring magneto-rheological damper is designed,which relieves the traditional magnet-orheological damping to some extent.The problem of fail-safe and static settlement of magnet-orheological fluid exists in the device and achieves the purpose of energy recovery.(2)Based on the theory of electromagnetism,a mathematical model of the magnetic induction intensity in the damping channel is established.Combined with the Bingham fluid constitutive model,the mechanical model of the built-in permanent magnet ring magneto-rheological damper is deduced;through the dynamic analysis of the ball screw,The mechanical model of the energy-feeding device was constructed;the magnetic model of the magneto-rheological damper with built-in permanent magnet ring was finally completed.(3)Based on the theory of vehicle dynamics,the simulation model of two-degree-of-freedom 1/4 vehicle body suspension is established using Matlab/Simulink simulation software.At the same time,an energy recovery simulation model is established based on the structural characteristics of this type of damper.(4)According to the suspension simulation model and energy recovery simulation model established above,under the guidance of the sliding mode control theory and the fruit fly optimization algorithm theory,a control algorithm with excellent control effect is designed for the semi-active suspension system,and simulation analysis is performed.Verify the effectiveness of the algorithm.The input signal under a variety of operating conditions is used as the road surface input for simulation modeling,and the simulation results of the control algorithm are compared with other control algorithms,indicating that the designed control algorithm can effectively improve the suspension reduction compared to other control algorithms.At the same time,a energy-feedback simulation experiment will also be conducted to examine the energy recovery efficiency of the energy-feeding damper.(5)Whether the built-in permanent magnet ring type magnet-orheological damper designed for inspection can meet the requirements of the automotive suspension,and complete the test by combining the structural features of the energy-feeding type built-in permanent magnet ring magnet-orheological damper.The platform is set up,and under different input excitation signals,the dampers are exposed to show work tests,and the test results are analyzed and compared to check whether the designed dampers can meet the working requirements.At the same time,energy recovery tests were conducted under both no-load and load conditions to check the energy recovery efficiency of the energy-feedback type damper.