Insulating properties of transformer oil-based silica nanofluids

Two types of colloidal dielectric fluids with 20% concentration of nanoparticles are manufactured by dispersing SiO2 nanoparticle with transformer oil by different preparation methods in order to improve the dielectric properties of mineral oil. The AC breakdown voltage of pure oil and prepared nanofluids were measured according to IEC standard methods at 20ppm. The AC breakdown voltages of two nanofluids were 1.05 times and 1.11 that of base oil respectivelyThe possible modification mechanism of silica nanoparticles on insulating properties of transformer oil was discussed on the trap characteristics of host oil and nanofluids. The results confirmed that mineral oil modified with Silica nanoparticles hold a promise to improve its insulating properties.