Mathematical Model for Numerical Simulations of Relaxor Ferroelectric and Antiferroelectric Fillers for Nonlinear Refractive Field Control Materials in High-Voltage Insulation Systems

As a result of their special polarization behavior antiferroelectric (AFE) and relaxor ferroelectric (RFE) materials are promising materials for nonlinear refractive field control in future AC insulation systems, especially in gas insulated systems (GIS). Their unique switchable dielectric behavior enables the design of even more compact power supply components. To identify potential applications of these materials, their functionality was investigated by FEM simulations. For this purpose, a mathematical model based on the polarization properties (P-E-curve) of RFE and AFE material was implemented by using the interface between MATLAB and COMSOL Multiphysics®. To verify the theoretical model, epoxy resin samples with different filler concentrations of lead-free RFE (sodium bismuth titanate) and lead-free AFE (sodium niobate) were prepared, their nonlinear dielectric properties characterized and compared with the results of the FEM simulations.