Influence of Fe₃O₄, TiO₂, and Al₂O₃ Nanoparticles on Dielectric Strength of Natural Ester Oils

Recent studies show that adding nanoparticles (NPs) in conventional liquid dielectrics can improve their insulation performance and also improve their thermal properties. However, the effects of NPs on the electric field and breakdown strength of nanofluids (NFs) are to be better understood for the improved insulation design. This paper analyses the theoretical aspect of the charge capture process of nanoparticles placed in between the electrodes under a uniform electrical field. In this study, natural ester oil (NEO-FR3) is utilized as the base insulating fluid, and three types of NPs are investigated: conductive (Fe<inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</inf>O<inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">4</inf>), semiconductive (TiO<inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</inf>), and insulating (Al<inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</inf>O<inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</inf>). The behaviour of these nanoparticles under electric fields is analyzed, focusing on their influence on the breakdown strength of the resulting nanofluids. The findings of this work discuss the theoretical aspect of different NPs on breakdown strength, emphasizing the charge capture mechanisms of each type of nanoparticle and their role in enhancing or altering the breakdown performance.