Inhibition of Tree Degradation of Dielectrics via Shallow-Trap Engineering under High-Temperature and High-Frequency Conditions

Abstract

Electrical treeing is a key failure mode of solid dielectrics. Differing from the conventional deep-trap strategy, this study introduces an innovative shallow-trap engineering approach to inhibit tree growth under combined high-temperature and high-frequency stresses. On the basis of molecular-orbital energy-level calculations, 1,4-diaminoanthraquinone (DAAQ) was selected as the grafting functional molecule and chemically incorporated into a bisphenol A epoxy resin (DGEBA) matrix, thereby creating a high density of shallow traps in the polymer network. The results demonstrate that DAAQ grafting reduces the electrical tree growth rate by up to 97.27%, thereby significantly inhibiting growth under high-temperature and -frequency conditions. The inhibition mechanism originates from the repeated trapping–detrapping of carriers at shallow sites, which effectively dissipates the kinetic energy of high-energy charge carriers and retards the insulation degradation process.