3D eddy current formulation for moving conductors with variable velocity of coordinate system using edge finite elements

A general formulation for moving conductors using 3D edge finite elements is introduced. In the formulation, the velocity of the coordinate system can be selected arbitrarily. A proper gauge condition for this formulation is also indicated. The optimal velocities of the coordinate system are investigated by numerical experiments. It is clarified that the accuracy of the analysis depends on the time variation of electromagnetic fields, which are observed differently in each coordinate system. From this point of view, we introduce a novel method that uses several different coordinate systems in one conductive region.