Effective material modelling for laminated iron cores with an <i>A</i>-formulation and circuit coupling

Purpose This study aims to introduce an effective material to efficiently and accurately solve the eddy current problem in laminated iron cores considering circuit coupling. Design/methodology/approach In the first step, a representative cell problem is solved to obtain the complex-valued non-linear magnetic reluctivity. In the second step, this effective material is then used in a homogenised static magnetic field formulation and accurately approximates the eddy current losses and the reactive power as well as the corresponding distributions. Findings As a representative numerical example, a voltage-driven single-phase transformer is simulated with great success. The eddy current losses and the reactive power of the simulation using the standard finite element method and the simulation using the effective material agree very well and the required simulation time is tremendously reduced. Originality/value The presented approach uses an A-formulation with circuit coupling of voltage-driven excitation coils for an effective material to homogenise the core.