Analysis of 3D nonlinear eddy current problem using the field variables H and E directly

The 3D nonlinear eddy current fields in the steel plates of TEAM Problem 21 are analyzed by using H and E directly as state variables respectively. The boundary conditions of the eddy current region are provided by means of the surface impedance method based on two magnetic scalar potentials. The calculated values of eddy current losses are compared with the measured values, and the results indicate the presented methods are valid. Furthermore, the dual-complementary phenomena between the lower and upper bounds of the eddy current losses and reactive powers are numerically shown when H-oriented formulae and E-oriented formulae are separately used. For the nonlinearity of permeability of the steel plate, an equivalent permeability μ_c , and the finite element technique of frequency domain are employed to solve directly the governing equations by using the Newton-Raphson algorithm