The Influence Mechanism that Micro Grain-Boundary Structure Parameters of ZnO Varistor to the Macroscopic Electrical Characteristics

ZnO varistors have excellent nonlinear voltage-current characteristics, are widely used in overvoltage protection of electrical equipment. The nonlinear behavior of ZnO varistors is attributed to the double Schottky barrier structure of their grain boundaries. However, few studies have investigated the influence of micro grain-boundary structure parameters on the macroscopic electrical properties of ZnO varistors. In this paper, we utilized the Voronoi network and an improved grain boundary partitioning model to simulate and calculate the impact of micro grain-boundary parameters, such as double Schottky barrier and grain boundary partitioning parameters, on the macroscopic electrical properties of ZnO varistors. By classifying and optimizing grain boundary characteristics based on their effects on classification variables and targets, we effectively simplified the complex multivariate and multi-objective problem. These findings provide insight into improving the performance of ZnO varistors, and are of significant importance for the production of high-performance ZnO varistors.