Abstract
There is a need to develop upgraded insulant which offers superior dielectric properties than mineral oil in terms of cooling, insulation, and efficient functioning under extreme weather conditions. These oils are nanofluids that are synthesized by dispersing nanoparticles in the oil. These fluids are tested with their ability to withstand various faults under operating conditions by determining the dielectric and electrical properties like ac breakdown strength, relative permittivity, and dielectric dissipation factor. A comparison between nanoparticles and their effect on insulating oils has been widely discussed and presented. In this study, three nanoparticles namely Fe 3 O 4 , TiO 2 , and Fe-Cu are dispersed in three different types of oils namely mineral oil (i.e., transformer oil used as insulating liquid in transformers), synthetic ester oil (i.e., pentaerythritol ester), and rapeseed oil (natural-ester transformer fluid). These nanofluids are considered upgraded insulant due to its superior insulation characteristics compared to pure mineral oil. Synthetic ester-based oils and natural rapeseed oil are tested for insulation capabilities for better results, which show they have all the potential to replace transformer oil in high voltage equipment's.