Investigation of Dielectric Properties of TiO2 and Al2O3 nanofluids by Frequency Domain Spectroscopy at Different Temperatures

Abstract

In this paper, frequency dependent dielectric parameters of pure oils and nanofluids have been studied at different temperatures to investigate any improvement of the dielectric properties due to the presence of nanoparticles. In power transformers, mineral oil is popularly used as an insulating material. However, mineral oils have inherent drawbacks associated with fire hazards and environmental issues. So, as an alternative, vegetable oils are drawing more attention of the researchers in this field. But, pure vegetable oil exhibits weak dielectric properties to be used under high electric stresses. Considering the drawbacks, extensive research work is going on to improve the dielectric strength of eco-friendly vegetable oils by using nanoparticles as additives. In this work, nanoparticles (TiO2 and Al2O3) based mineral and vegetable (FR3) oil samples have been prepared in laboratory for investigation of their dielectric properties for use in high voltage equipment through frequency domain spectroscopy. The dielectric dissipation factors obtained from FDS measurement have been compared for the aforesaid liquids. Furthermore, frequency domain spectroscopy has been conducted on pure oils and nanofluids at different temperatures to study the effect of temperature on their dielectric properties. Based on the experimental results, LFD of the insulation has been investigated to obtain an idea about aging status of it.