Silicone rubber dielectrics modified by inorganic fillers for outdoor high voltage insulation applications

Abstract

The paper discusses the mechanisms by which inorganic fillers in silicone rubber dielectrics enhance the properties of thermal conductivity, relative permittivity, and electrical conductivity making them useful in outdoor high voltage insulation applications. The addition of alumina trihydrate or silica fillers to silicone elastomers, forming binary composites with enhanced thermal conductivity, is discussed in relation to filler type, particle size, shape, and concentration, and its use as a housing material for non-ceramic insulators to minimize material erosion at dry band arcing sites by lowering hot spot temperature. Also discussed is the enhanced relative permittivity of silicone dielectrics that is obtained through the addition of barium titanate powder which can be further increased with the addition of aluminium powder forming a tertiary composite, resulting in a significant grading of the surface electric field when applied as a housing material to high voltage bushings. Controlled electrical conductivity of silicone dielectrics is discussed through the use of antimony-doped tin oxide filler binary composites and when applied as a housing material to outdoor bushings, the pollution performance is greatly enhanced.

Low dielectric permittivity and high thermal conductivity silicone rubber composites with micro-nano-sized particles

“…Another important characteristic of the SR composites should have relatively low dielectric permittivity which is one of the most crucial properties of dielectric materials for the applications in electrical and electronic system. 16,17 Though a lot of studies have been done about how to improve the thermal conductivity of SR composites, the study on the relative dielectric permittivity of thermally conductive SR composites has not been attracted much attention.…”

Exploring the influence of co-monomer content in the dry crosslinked ethylene octene copolymer based blends

“…But is has some disadvantages like high cost, inferior physico-mechanical properties, poor resistance to wear and tear. Hence, the PDMS rubber is blended with several polymers mainly polyolefins or made into composites using nanofillers [11][12][13][14][15][16].…”

Electrical field and potential distribution of polymer insulators under the influence of a three phase supply

“…Most of the laboratory testing and simulation work in the past have been carried out using a single phase supply, with an assumption that the effect of the other two phases is negligible [16][17][18]. However, in an actual insulator setup, where a three phase supply is used, the electrical field could be higher than that of the testing conditions due to the presence of the two neglected voltage sources.…”