Eddy current losses in composite and/or multibodies with μr≥1

Abstract

The paper deals with the computation of eddy current losses in composite and/or multiconducting cylinders due to time-harmonic transverse magnetic fields. The cylinders are linear magnetic or nonmagnetic with an arbitrary cross-section area. Two diffferent formulations in terms of the Fredholm integral equations of the second kind are used. The exact formulation comprises 2N (where N is the number of conductors) coupled one-dimensional integral equations; and the second, where the external impedance boundary condition approach is used, consists of N coupled one-dimensional integral equations. With the proper choices of the equations the highest singularity in both formulations is logarithmic (weak singularity in 2D). Numerical results are computed for the special case of a pair of circular conductors. Magnetic and nonmagnetic materials are considered and the results are compared with the corresponding results for a single circular conductor.