PDIV Characteristics of Natural Ester-Based Nanofluids and the Impact of Varying Moisture Content Under Oxidative Aging

Nanofluids (NFs) are an emerging dielectric technology used in transformers and power equipment for insulation and cooling. It provides enhanced dielectric strength, thermal characteristics, and biocompatibility as a viable substitute for liquid insulation. This study investigates the partial discharge inception voltage (PDIV) of varying moisture content levels in TiO<inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</inf> and exfoliated hexagonal boron nitride (Eh-BN) nanofluids based on natural ester oil (FR3). The research is conducted using specific volume percentages and subjected to an oxidative aging process over a 400-hour duration. A comparative analysis of the electrophysical properties is carried out for both nanoparticles in natural ester oil. PDIV tests (IEC 61294TR) used a needle-plane setup with a needle tip radius of 20 μm and a 50 mm diameter ground electrode. The impact of moisture levels on PDIV measurements is evaluated in two nanofluids, with 0.01% concentrations of TiO<inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</inf> and Eh-BN nanoparticles dispersed in the FR3 base fluid. The article explores the partial discharge inception voltage (PDIV) estimation from PD characteristics with varying moisture content levels in nanofluids.