Research On The Structure And Performance Of Electromagnetic Active Suspension Actuator

With the mature development of automobile "three electricity" technology and the strong support of national policies for new energy vehicles,more low-carbon and intelligent new energy vehicles have become the mainstream direction of the development of automobile industry.The performance of the active suspension system has a great impact on the driving quality of the vehicle.It suppresses the body vibration by outputting the active force from the actuator to meet the requirements of vehicle driving smoothness and ride comfort.In this study,in order to reduce the output electromagnetic force fluctuation of electromagnetic linear actuator and improve the stability of active suspension system,the mathematical model of actuator is established,the structure of actuator is optimized by multi-objective particle swarm optimization algorithm,and the dynamic characteristics of actuator are analyzed by joint simulation platform.Considering the spatial layout of the electromagnetic active suspension and the installation position of the electromagnetic linear actuator,the structure of the electromagnetic linear actuator is designed,the 1/4 vehicle suspension dynamics model is built,and the LQG ideal control strategy is designed.The ideal suspension performance is obtained as the design goal of the actuator,and the structural parameters of the actuator are determined.The simulation model is established by using the finite element software Maxwell,and the reliability of the finite element model(FEM)is verified according to the prototype experiment;The subdomain modeling method is used to establish the magnetic field mathematical model of electromagnetic linear actuator,and the mathematical models of induced electromotive force(EMF)and output electromagnetic force are further deduced.The reliability of the mathematical model is verified according to the calculation results of the FEM;Combined with the mathematical model and FEM of electromagnetic linear actuator,the main components of actuator thrust fluctuation are analyzed.Aiming at the problem of actuator thrust fluctuation,the parameter sensitivity of actuator primary length,air gap thickness and polar arc coefficient is analyzed,and the parameters are optimized by multi-objective particle swarm optimization algorithm;In order to test the dynamic performance of the actuator in operation,based on the structural optimization of the actuator,the field circuit coupling co-simulation model of the actuator is established by using Simplorer and Maxwell,and the performance and anti-interference ability of the actuator drive system during starting,loading and acceleration are analyzed and tested.After the parameters of electromagnetic linear actuator are optimized by multi-objective particle swarm optimization,the primary length,air gap thickness and pole arc coefficient are optimized to 187.6mm,0.9mm and 0.77.The average output electromagnetic force of the actuator before optimization is 134.4N,and the average output electromagnetic force after optimization is 145.5N,which is 8.2%higher than that before optimization.The electromagnetic force fluctuation value before optimization is 7.98N,and the electromagnetic force fluctuation value after optimization is 5.06N,which is 36.6%lower than that before optimization.The amplitude of induced EMF before optimization is 7.735V,and the amplitude of induced EMF after optimization is 9.282V,which is 20%higher than that before optimization.The total harmonic distortion(THD)rate is 6.4%before optimization and 5.51%after optimization,which is 14%lower than that before optimization.After analysis,the average value of the output electromagnetic force and the amplitude of the induced EMF are improved,and the fluctuation value of the electromagnetic force and the THD rate are suppressed;The analysis of the co-simulation results of the actuator shows that the actuator can basically meet the requirements of the suspension system for vehicle damping performance.At the same time,the control system designed in this study has strong dynamic response ability such as starting,loading and speed-up,as well as anti-interference ability.