Dielectric relaxation assessment of a heat treated metal oxide varistor

The dispersion of the dielectric constant and the electrical conductivity of a metal oxide varistor depends on the heat treatment procedure during the production process of the device. This dependence is investigated quantitatively using a multiple-arc approach that yields the dielectric relaxation of the material. This analysis method provides an equivalent network representation that adequately simulates the experimentally measured data for devices produced using different heat treatment temperatures. The distributed and discrete networks derived from the proposed approach can be either passive or active in nature. The latter type is used to account for the negative capacitance introduced by the arc analysis.