Thermal stability and organic component analysis of HTV silicone rubber composite insulator

Compared with ceramic or glass insulators, composite insulators featuring light weight, good water repellency and hydrophobic- migration are more suitable to operate in heavy-polluted areas. However, polymer materials such as silicone rubber are much more vulnerable to environmental stresses such as sunlight, UV radiation and intense electric field strength and as a result, showing aging phenomena and performance degradation. In this paper, thermal analysis method such as Thermal Gravity Analysis (TGA) and Differential Scanning Calorimetry (DSC) were applied to study the change of organic component in HTV silicone rubber composite insulators. Thermal analysis kinetics methods were applied to calculate the activation energy of 18 composite insulators of which performance period ranges from 20 to 180 months. Test and calculation results indicate that thermal analysis methods could make a great contribution to the performance assessment of composite insulators.