Ageing analysis of mineral insulating oils using CCTO Nanofluids

Power Transformers are one of the most critical component of power system in which mineral oil is used for both insulation and cooling purposes. It acts a insulating medium between solid insulations like kraft paper, pressboard etc. In transformer, dielectric strength of insulation materials mainly depends on the properties of the transformer oil. In this work, a comparative analysis can be made with pure and aged mineral insulating oil using high dielectric permittivity CCTO(CaCu₃Ti₄O₁₂) nanopowder and its electrical and physical properties are investigated. Nanopowder is added with mineral insulating oil under various particle volume fractions to form nanofluids (NF´s). The electrical and physical properties like breakdown voltage, loss tangent, viscosity, interfacial tension, flash point were measured at room temperature under IS standards. It was observed that breakdown voltage and flash point of pure and aged mineral oil shows improved results after the addition of nanopowder with respect to increase in particle volume fractions and temperature.