Research On Control Strategy Of Energy-Fed Multi-mode Active Suspension

Active suspension can effectively attenuate the vehicle body vibration caused by road excitation.A good active suspension control strategy can also better adjust the vehicle body attitude in real time and improve the dynamic performance of vehicle driving.However,due to the large energy consumption and the single active suspension control strategy is difficult to meet the complex and changeable working conditions,its application is limited;at the same time,the suspension system mainly converts the vibration energy caused by the road excitation into heat energy and releases it to the outside,resulting in a large amount of energy waste.Therefore,how to improve the control effect of suspension and effectively recover the vibration energy of suspension to reduce vehicle energy consumption has become a hot research topic.In order to solve the problem that active suspension can’t recover the vibration energy and the control effect of control strategy is poor under variable working conditions,this paper proposes a multi-mode active suspension system based on the hybrid actuator of electromagnetic force and hydraulic force,and studies its control strategy,aiming to improve the ride comfort and stability of the vehicle,while effectively recovering the vibration energy of the suspension.The main contents of this paper are as follows:Based on the analysis of the structure and working mechanism of the energy fed suspension,the dynamic model and the road model of the energy fed active suspension system are established,and the linear motor model and the hydraulic damping force calculation model are established to complete the construction of the actuator model of the hybrid active suspension system;Comparing the advantages and disadvantages of various active suspension control strategies,the fuzzy sliding mode control strategy is adopted and the control parameters are designed and calculated;the linear motor control strategy is designed and the current hysteresis control strategy is designed to track and control the optimal electromagnetic active damping force,at the same time,the energy feedback strategy of active suspension system is designed and modeled to improve the energy feedback of suspension system Based on the principle of switching system,the working mode and mode switching conditions of active suspension are defined and analyzed,and the mode switching strategy is designed by combining the suspension control strategy,and the stability of the mode switching system is designed,tested and evaluated.The simulation and experimental verification of the multi-mode active suspension system model are carried out.The simulation and experimental results show that the designed active suspension control strategy can effectively improve the dynamic performance and energy feedback when the vehicle is driving,and the energy recovery efficiency of the suspension system can reach about 16%-18% when it is valuable to carry out energy feedback;when driving under different conditions,the dynamic performance of the suspension system is improved by switching the working mode,and the energy feedback is also improved It is verified by bench test.Based on d SPACE controller,energy feedback circuit and bench test,the energy feedback performance of suspension system is studied.The experimental results show that: using the feedback control to output the duty cycle of switch signal in the energy feedback circuit,and setting the optimal initial terminal voltage of super capacitor according to the actual needs can effectively improve the energy feedback ability of suspension system.