The Control Algorithm Research For Semi-active Suspension Based On The Electromagnetic Damping

When the vehicles travel on the road,suspension plays an extremely important role in comfort and safety of the vehicles.With the demand improvement of society,people have higher requirement on the properties of vehicles.With energy saving,environmental protection,comfortable performance of the vehicle has become more and more popular.In recent years,the semi-active regenerative suspension becomes a research focus in the automotive industry.The semi-active regenerative suspension which combines the advantages of both conventional and active suspensions it provides abilities in optimizing passenger comfort while ensuring safety requirements.Simultaneously the vertical vibration energy of the vehicle is recovered as electric energy to achieve the goal of energy saving.This paper presents a new electromagnetic regenerative suspension,which contains a regenerative motor and a ball screw in series and keeps the spring from the conventional suspension,analyzes the dynamic characterizes and proposes the damping force model of the electromagnetic regenerative suspension.This paper considers the interference of the space and time between the four tracks,a time domain model for the road excitation irregularity on four-wheel vehicle is established based on “Filtered White Noise method”,and the model of the road excitation is tested.This paper constructs a 7-DOF full-vehicle mathematical and simulation model containing electromagnetic regenerative suspensions by MATLAB/Simulink.The model is compared with the 7-DOF full-vehicle mathematical and simulation model containing traditional suspensions.This paper analyses the effects of inertial mass on natural frequencies of full-vehicle body and wheels,the transfer characteristics of car body and four wheels under road excitation and the riding comfort and handling stability of the vehicle.For the controller,this paper develops the fuzzy logical control(FLC)algorithm and matrix pseudo inverse method to control the full-vehicle containing electromagnetic regenerative suspensions,this paper analyses the influence of the full-vehicle’s riding comfort and handling stability.The full-vehicle containing electromagnetic regenerative suspensions are decoupled through Decoupling Transformation.Different control rules for different vehicle body motions,including vertical,pitch and roll,are developed.Through three independent fuzzy logic controllers that control vertical,pitch and roll motions,vehicle body poses are correspondently controlled in MATLAB/Simulink.At the same time,vertical vibration energy of the full-vehicle can be recovered as electric energy,and the regenerative characteristic of electromagnetic regenerative suspensions are analyzed after the FLC.