Perturbation finite-element method for magnetic circuits

Accurate magnetic flux distributions are calculated in magnetic circuits via a subproblem finite-element (FE) method based on a perturbation technique. An approximate FE problem considering ideal flux tubes is first solved. It gives the source for FE perturbation problems considering the flux tubes with their exterior regions, accounting thus for leakage fluxes, as well as for changes of material properties and shapes. The proposed technique aims to accurately quantify the gain given by each model refinement on both local fields and global quantities and to justify the usefulness of this refinement. It is also well adapted to parameterised analyses on geometrical and material data.