Retreatment of aged mineral oil using semiconductive nanocomposites for power transformer application

Abstract

Summary Power transformer plays a vital role in power system network, and it mainly consists of liquid and solid insulations. In this mineral oil plays a major insulation role and cooling purpose. Moisture and prolonged electric stress leads the way for ageing in transformer insulation. It results in degradation of insulation properties and hindrance in uninterrupted operation. Due to thermal degradation, insulation loosens its dielectric withstand properties. To avoid this, periodic condition monitoring is required to protect the transformer insulation. In this work, an effort has been taken to investigate the aged mineral oil using semiconductive nanocomposites by retreatment technique. The nanocomposites are added with the aged oil in different volume fractions to evaluate the enhancement level of aged oil for reutilization purpose. The critical properties like breakdown voltage, dielectric loss, resistivity, dielectric permittivity, viscosity, flash point, and acidity of the samples before and after treatment are measured according to American Society for Testing and Materials (ASTM) and International Electro‐technical Commission (IEC) standards. It is found that semiconductive nanocomposites improve the critical properties of aged oil and suitable proportion of volume fractions shows impressively enhanced results than base fluid samples. The result paves a new way in economic retreatment of aged oil under environmental friendly nature for reutilization purpose.

Breakdown in Nanofluids: A Short Review on Experimental Results and Related Mechanisms

“…An improvement of breakdown strength of aged transformer oil by adding nanoparticles of either ZnO or TiO 2 in volume concentrations w/v% of 0.001%, 0.0015%, and 0.002% was observed in [85]. 10-and 20-year old oils were treated with nanoparticles and showed a satisfactory recovery in breakdown strength.…”