The Perturbation Finite Element Method for Magnetic Modeling of a Loudspeaker

This paper shows that the application of a perturbation finite element method can provide a useful alternative to correct the equivalent magnetic circuits used to model loudspeakers. A ring magnet design of a loudspeaker is modeled by means of an axisymmetric magnetic vector potential formulation. The effects of geometry variations on its performances are analyzed. The perturbation solution allows further adapting and refining the equivalent magnetic circuit model of the loudspeaker to each possible variation. Results will be compared with the classical finite element solution.