Design And Optimization Of Annular Magnetic Circuit MR Damper

Suspension is the key component to buffer the impact of the road,and the performance of which directly affects the comfortability of the car.Magnetorheological(MR)damper is the core component of the new type of electromagnetic semi-active suspension,which has the advantages of fast response,continuous adjustable damping force,wide adjustment range and low energy consumption,etc.In this case,the details about the design and optimization of MR damper are as follows:Firstly,based on the Bingham model and damping channel plate model,the valve MR damper damping force model was established,and based on the magnetic circuit Ohm’s law,the magnetic induction intensity model was established.In order to verify the correctness of the theoretical model and further study the two-stage coil MR damper,based on the established theoretical model,the prototype of MR damper was designed and processed,and the relevant bench test was conducted.The dynamometer diagram and speed characteristic curve of the prototype were obtained.The results showed that the performance of the designed prototype was up to standard,and the theoretical value was consistent with the test results.So,the established mathematical models are accurate and effective.Secondly,in order to solve the disadvantages of uneven magnetic field distribution of the two-stage coil MR damper,a new type of MR damper was proposed.The magnetic circuit has a simple structure and consists of four arc-shaped solenoids.Taking the prototype of the two-stage MR damper as the design goal,the structural design and parameter selection of the annular magnetic circuit MR damper were carried out.Then,using the improved non-dominated sorting genetic algorithm(NSGA-II),taking the response time γ,energy consumption P,maximum stroke S,and power adjustment coefficient λ as optimization objectives,and the relevant performance requirements and space constraints as constraints,the MR damper was optimized,and an optimal design parameter was selected according to the optimization result.Thirdly,Ansoft magnetic field finite element analysis was performed on the new MR damper.The results show that the magnetic field distribution is uniform,the magnetic field at the edge is rapidly weakened,and the magnetic flux leakage is less.Through the simulation of the damper performance,it is found that under the premise of smaller piston length,the performance of the new damper reaches and surpasses the two-stage coil MR damper,which proves the superiority of the new structure.By studying the valve MR damper,it was found that the annular magnetic circuit MR damper is superior to the two-stage coil MR damper in magnetic field distribution and stroke optimization.The work has practical application value and provides a new ideas for the research of the MR damper.