A Comparative Study on Thermal Aging Characteristics between Silicone Rubber and Epoxy Resin for Dry-Type Transformer

Epoxy resin (EP) and silicone rubber (SIR) are commonly used insulating materials in dry-type transformers. In this paper, the electrical, mechanical, and thermal stability properties of SIR and EP are compared under thermal aging conditions at
${{180}^ \circ }\mathrm{C}$
. The results indicate that the SIR has a higher activation energy, less long-term performance degradation, and better stability at high temperatures compared to EP. Additionally, while EP has greater tensile strength and lower elongation at break, SIR shows less decline in mechanical performance after aging, suggesting a longer service life. When considering SIR as a possible replacement for EP, it is important to pay attention to its aging performance over the expected service life to ensure sufficient insulating properties and mechanical strength. These findings provide important reference for the selection of insulating materials for dry-type power equipment.