Analysis And Optimal Control Of Vehicle Semi-active Air Suspension System Based On Damping Multi-mode Switching

The semi-active air suspension can effectively meet the requirements of vibration isolation performance in a wide range of operating conditions by adjusting the damping state of the dampers in real time,and has become one of the research hotspots in the field of vehicle suspension.However,although the dampers with adjustable orifice area and adjustable oil viscosity have been able to achieve good damping performance from the functional point of view,there are still problems such as high cost,complex design and high energy consumption from the practical application angle.Accordingly,this paper proposes a new type of semi-active air suspension system with damping multi-mode based on high-speed solenoid valves,and analyzes its damping adjustment characteristics and damping control strategy.Specific research for the paper included the following:Firstly,the structural design and model construction of the semi-active air suspension system based on damping multi-mode switching is completed.The mathematical model of the semi-active air suspension system is established by analyzing the working principle and structural characteristics of the semi-active air suspension system based on high-speed switching solenoid valves.On this basis,system parameters such as the stiffness of the air spring,the optimal damping ratio of suspension system and damping coefficient in each gear are determined according to the target vehicle parameters.Secondly,the simulation of mechanical properties and experimental verification of the new semi-active air suspension based on damping multi-mode switching are carried out.Based on MATLAB,a simulation model of suspension system is constructed to analyze the influence of the key parameters of the damping regulation device on the damping characteristics of the damper.On this basis,the main structural parameters of the damping regulation device are determined.A prototype of the semi-active air suspension system with damping multi-mode is produced,and the prototype test is conducted to verify the consistency of the mechanical characteristics test results with the simulation.Thirdly,the control strategy of damping multi-mode switching which based on fuzzy neural network control logic is designed.Based on the vertical vibration model,the system fuzzy control logic is formulated,and the optimization design of fuzzy control based on BP neural network is completed.The damping control performance is analyzed by simulation,the simulation results show that the vehicle semi-active air suspension system based on damping multi-mode switching control strategy can significantly improve the system vibration isolation performance.Finally,the bench test of the semi-active air suspension system based on damping multi-mode is completed,and the system damping control algorithm is implemented in combination with the dSPACE rapid control prototype.The effectiveness of the fuzzy neural network control strategy is demonstrated by conducting the system bench test.