Vibration Reduction of Inductors Under Magnetostrictive and Maxwell Forces Excitation

This paper analyzes the phenomenon of vibrations in U-shaped (two-limb) inductors with distributed air gaps due to both Maxwell and magnetostriction forces. A weak 2-D magnetomechanical finite-element model (FEM), including magnetostrictive tensor, is developed under the GetDP open-source simulation environment. A simple analytical model of the reactor core vibration under magnetic forces is established and validated using the FEM model. The resonance effect of magnetostriction and Maxwell forces on the inductor structure is analyzed, and a sensitivity analysis is run on some of the inductor geometrical parameters. An example of inductor is presented, and a methodology to reduce vertical vibrations under magnetic force excitation is proposed by opposing the magnetostrictive and Maxwell forces. This technique is validated using both the analytical and the FEM models.