Abstract: A new type of electromagnetic linear actuator for vehicle active suspension is designed, with the characteristics of large stroke and force and fast response. Combined with the finite element analysis software, the effects of actuator structure parameters such as gap thickness, secondary stainless steel tube thickness, secondary copper layer thickness, magnetic permeability and electrical conductivity of insulated retainer ring and primary coil winding mode on actuator thrust size and response speed are studied. And the effects of actuator power parameters such as voltage, frequency and loading mode on actuator thrust size and response speed are also studied. The results show that the electromagnetic force is closely related to structural parameters such as the gap thickness, except for the conductivity of insulated retainer ring. And the electromagnetic force is proportional to the square of the voltage, and first increases and then decreases with the increase of frequency, getting the maximum at 20 Hz. Based on the simulation results, a prototype of electromagnetic linear actuator with appropriate parameters is developed. And the steady electromagnetic force and phase current test of the actuator is carried out. Comparison between the finite element simulation results and the experimental data shows they are basically consistent, thus verifying the correctness of the relevant design and analysis.

Key words: Active suspension, Electromagnetic linear actuator, Finite element analysis, Vehicle