Permittivity Calculation Model for Low Permittivity Characteristic of Epoxy/Hollow Silica Nanocomposites

To achieve a low permittivity solid insulator for HV power apparatus, we have developed an epoxy composite filled with hollow silica nanoparticles (epoxy/hollow silica nanocomposite). It has become clear that the relative permittivity of epoxy/hollow silica nanocomposite is lower than that of unfilled epoxy. In this paper, a permittivity calculation model of epoxy/hollow silica nanocomposite was constructed using the finite element method (FEM). The relative permittivity by the model calculation corresponds with the result of the capacity measurement on the actual epoxy/hollow silica nanocomposite. Therefore, it is confirmed that the low permittivity characteristic of epoxy/hollow silica nanocomposites is due to the hollow structure of nanoparticles.