Effect of titania nanoparticles on the dielectric properties of transformer oil-based nanofluids

In this paper, a study on the dielectric properties of transformer oil-based nanofluids is presented. Titanium oxide nano ceramic particles, known as titania nanofillers, was used in the investigation process. The nanofluid samples were prepared using two-step method, in which, nanoparticles were mixed with the base oil and then dispersed using magnetic stirrer, dispersants and ultrasonic processor. Different amounts of dispersants were considered and the best amount of dispersant was determined according to the observed images obtained by an optical microscope. Different nanoparticle volume fractions were considered, starting from 0.1 g/L to 0.3 g/L. Breakdown strength was measured for the prepared samples using a liquid tester and then compared to that of the base oil. The breakdown strength increased significantly with the addition of nanofillers. The obtained results will enable to develop a new class of liquid dielectrics with a visibility for the application into power transformers.