An industrial application is presented to validate a finite element analysis of 3-dimensional, nonlinear eddy-current problems with periodic excitation. The harmonicbalance method and the fixed-point technique are applied to get the steady state solution using the finite element method. The losses occurring in steel reinforcements underneath a reactor due to induced eddy-currents are computed and compared to measurements.

The generalized magnetizing curve series for the nonlinear magnetic circuit is proposed. Subsequently, three definitions of selfinductance for the nonlinear magnetic circuit are compared. The passivity of the magnetic circuit is reconsidered. Three theorems that describe features of Fourier harmonics of distorted waveforms have been proved.