Research On The Multi-Mode Switching Control Of Electromagnetic Hybrid Active Suspension

The suspension is an important part of the vehicle,its performance directly affects the vehicle ride comfort and handling stability.The parameters of the passive suspension can not be adjusted to meet the performance requirements of the driver under different driving conditions.Compared with the passive suspension,the output force of the active suspension is controllable,which can play the superior performance under different driving conditions,but active control consumes more energy.In order to improve the damping performance of suspension under different driving conditions,reduce the active control energy consumption and recover the vibration energy of suspension.In this paper,an electromagnetic hybrid active suspension system is presented,and a multi-mode coordinated switching control strategy is designed.Based on the analysis of the structure and working principle of the parallel hybrid active suspension,the 1/4 vehicle two-freedom suspension model,the electromagnetic valve damper model,the linear electromagnetic actuator model and the random road excitation model are established.To divide the switching mode,and make the rules of switching mode.According to the different requirements of vehicle suspension performance under different driving conditions,the active and semi-active control modes are divided into comfort,comprehensive and safety modes,and the linear-quadratic-Gaussian control weighting coefficient is optimized by the improved Gravitation Search Algorithm.In order to improve the vibration damping effect of the suspension and reduce the energy consumption of active control,the control current of the solenoid valve in the corresponding mode is determined,the mode switching control strategy under active control is designed,and the simulation analysis is carried out.The mode switching control strategy under semi-active control is designed,the damping force-velocity characteristics of the linear motor are analyzed,the charging voltage of the energy-feeding circuit in different modes under semi-active control is determined,and the vibration reduction effect and energy consumption characteristics of the suspension are simulated and analyzed.Active and semi-active switching control strategies are designed,and the thresholds of active and semi-active control switching are determined through simulation analysis.Active and semi-active switching modules are designed,and the parameters of switching modules are analyzed and valued,and simulation analysis is performed to verify the effectiveness of the control strategy.A bench test scheme is designed,and a parallel electromagnetic hybrid active suspension test bench is built to verify the effectiveness of the multi-mode switching control strategy of the electromagnetic hybrid active suspension.The simulation results show that the control objectives of hybrid electromagnetic active suspension with multi-mode coordinated switching control are improved in different modes,and the active and semi-active control are switched reasonably.Compared with the semi-active suspension controlled by LQG,the mean square root of the load acceleration of the comfortable mode spring decreases by 31.09%,the mean square root of the dynamic load of the safe mode tire reduces by 32.20%,and the control energy consumption reduces by 14.93%,under semi-active control,the mean square root of the load-mass acceleration of the spring in the comfortable mode is reduced by 33.77%,the mean square root of the dynamic load of the tire in the safe mode is reduced by 31.58%,and the feed power is 101.5W.The results of bench test show that the difference of damping performance between mode switching under active control and mode switching under semi-active control is within 5%,the results show that the multi-mode coordinated switching control strategy is reasonable and effective.