Computational analysis of power frequency devices by a novel hybrid quasi-static finite difference–finite element technique

A hybrid explicit numerical methodology for the analysis of power frequency devices, characterized by large differences in permeability and conductivity values, is presented. It is based on the separation of the physical problem into two distinct ones according to the properties of the materials comprising the structure under investigation. A finite difference time-advancing scheme, specially modified for eddy-current analysis, is implemented in magnetic/conducting media, whereas in non-magnetic/non-conducting regions, like air, a finite element procedure is utilized. The two techniques are separately implemented and combined via appropriate interface boundary conditions into an efficient, systematic time domain procedure. The derived hybrid scheme is proved to be ideal for 2D power frequency problems.