Analytical Calculation of Magnetic Performance and Damping Characteristic Analysis of Permanent Magnet Electromagnetic Damper

Abstract

As a new type of permanent magnet arrangement, the Halbach permanent magnet array has gradually attracted wide attention for its excellent magnetic field utilization and self-shielding performance. Compared with other structural forms, the electromagnetic damper based on the Halbach permanent magnet array exhibits better magnetic field performance. Taking the Halbach permanent magnet array electromagnetic damper as the research object, its damping characteristics were analyzed. Firstly, the corresponding mathematical analysis model was established according to the structural form of the damper, and it was deduced analytically by using the layered theory. The finite element model was established to verify the analytical model. The calculation results show that the electromagnetic damping force is the largest when the relative velocity of the primary and secondary reaches the critical velocity value, and the electromagnetic damping force decreases if the relative velocity continues to increase. By introducing the artillery recoil motion equation, the damping force, recoil velocity and recoil displacement law of the electromagnetic damper under intensive impact load were analyzed to ensure that the recoil velocity does not exceed the critical velocity during the recoil process. The effects of different air gap widths and conductor cylinder thicknesses on the damping force were analyzed by the finite element method. The result shows that the electromagnetic damping force decreases with the increase of the air gap width; the electromagnetic damping force curve presents a"saddle"shape if the thickness of the conductor is too large. Reasonable selection of structural parameters can avoid demagnetization, and ensure that the designed electromagnetic damper can meet the requirements of use, which provides a reference for the design of electromagnetic dampers.