Effect of surfactant on breakdown strength performance of transformer oil-based nanofluids

Abstract

Many approaches to improve the transformer oil characteristics have been made by adding nanofillers into the liquids, but it has caused the existence of sedimentation and agglomeration thereby resulting in incompatibility of transformer oil. In view of foregoing, this paper aims to study the impact of cetyl trimethyl ammonium bromide (CTAB) surfactant added with the nanofiller in improving the compatibility and agglomeration issues towards improvement of breakdown voltage (BDV) characteristics of oil nanofluids. This study was carried out by implementing three different percentages of silica (SiO2) and alumina (Al2O3) nanofillers along with CTAB as surfactant into the mineral oil. The breakdown voltage test was carried out accordance to IEC 60156 standard. The results show that the inclusion of 0.1 wt% SiO2 and 0.1 wt% Al2O3 nanoparticles into mineral oil have improved the BDV. Meanwhile, Al2O3 nanofluids with 0.075 wt% CTAB had good impact on BDV but not on SiO2. This case has reverse behavior with the sedimentation which 0.1 wt% CTAB in SiO2 nanofluids has a good response but not the whole in Al2O3 nanofluids. This could be mainly due to the limitation stability of the nanofluids.