Exploring the Electrical Characteristics Of HTV Silicone Rubber Subjected To Multiples Stress Aging, Incorporating ATH, And Silica Filters /

Abstract

Silicone rubber (SiR) has seen a substantial increase in application for high voltage electrical insulation in outdoor conditions during the last three decades due to its exceptional properties, particularly its high hydrophobicity. However, because it is organic in nature, it deteriorates when subjected to multiple stresses, resulting in the loss of desired attributes that have a direct impact on their long-life. The loss in the characteristics prevent it from being widely accepted in the power system insulation as replacement of conventional ceramic insulators. Moreover, Inorganic fillers improve the dielectric and high voltage insulation properties, expanding potential applications of silicone rubber in many electrical appliances. The objective of this research is to investigate the electrical properties of multi stressed aged high-temperature vulcanized (HTV) silicone rubber (SiR) hybrid composites containing silica and Aluminium trihydrate (ATH) fillers. Five hybrid composites comprising of 20% micro-ATH with 2% nano silica (SAT-2), 4% nano silica (SAT-4), 6% nano silica (SAT-6), 8% nano silica (SAT-8), 10% nano silica (SAT-10) along with neat HTV SiR (SAT-0) were aged in the multi stressed aging chamber for 9000h, where they were subjected to multiple stresses like electrical, humidity, heat, and UV radiation. X-Rays Diffraction (XRD) was performed to confirm filler presence in composites. Additionally, the dielectric constant, dielectric loss w.r.t temperature and frequency, DC resistivity, as well as AC and DC leakage currents, were assessed both before and after stresses application. Notably, the DC resistivity exhibited a declining trend after the application of stresses. Furthermore, periodic increments in the dielectric constant, dielectric loss, and leakage current were observed. Interestingly, the SiR hybrid composites displayed a degree of resistance to the aging effects on their electrical properties when compared to the neat HTV SiR. Among the hybrid composites, the HTV silicone rubber composite containing 2% nano-silica (SAT-2) showed promising potential for applications in multi-stress environments over extended durations.