Coupled magnetoelastic finite element formulation including anisotropic reluctivity tensor and magnetostriction effects for machinery applications

This paper presents a generalized 2-D tensor finite element model, which can be used to evaluate force components in electromagnetic devices including those due to the magnetostrictive phenomenon. Magnetostriction is a property of ferrous alloys in which the material will exhibit strain in the presence of magnetic field. This strain is in addition to any other strains that might exist as a result of electrical and/or mechanical forces. At low frequencies, magnetostrictive forces are undesirable. These forces can be large and generate acoustic noise in electromagnetic systems. Implementation results on a 2-hp, permanent magnet motor show that magnetostrictive forces are significant and amount to more than 50% force level increase above electromechanical force levels obtained without accounting for magnetostriction.