Coupled transient finite element and boundary element method modeling of nonlinear, nonhomogeneous, electric field devices with mesh refinement

This paper introduces the structures of 2-D and 3-D finite and boundary element methods codes for calculating electric field strength distribution in high voltage insulation systems in arrangements with complex boundaries. A very accurate representation of the space distribution of electrical fields, varying in time as the combined effect of the circuit parameters, modulated by diffusion and time changing properties of the dielectric materials can be the basis for a global performance criterion for the system, large enough to represent the complexity of the phenomena, but still simple to be meaningful. Also, the paper describes a promising technique for rezoning the mesh in order to achieve a high resolution in critical areas of high field strength.