Influence of Temperature on Electrical Properties of POSS/Mineral Oil based Nanofluids

Polyhedral Oligomeric Silsesquioxane (POSS), a nanometric hybrid molecule, is being paid great attention in the field of polymeric micro and nanodielectrics, providing strong dispersion and dissolution power in solid and liquid dielectric materials which overcomes the sedimentation and agglomeration issues in nanocomposite insulation materials. This work presents the effect of temperature on electrical properties of Octa-isobutyl POSS (Oib-POSS) mineral based nanofluids prepared with two different concentrations 0.1 and 0.15 wt. % and the results are compared with fresh mineral oil. Dielectric properties that include relative permittivity, dissipation factor and volume resistivity along with the AC breakdown voltage are analyzed within a temperature range of 0-80°C in agreement with the IEC standards. Finally, 2-parameter Weibull analysis is performed over the AC breakdown voltage to validate the consistency of breakdown results. It is found that the POSS nanofluids show improved AC breakdown strength and dielectric properties e.g. relative permittivity, dissipation factor and volume resistivity compared with virgin mineral oil in entire temperature range. The results also show that the increase of POSS concentration not only improve the dielectric properties but also enhance the AC breakdown strength of mineral oil.