Streamer Simulation in Nano-Based Dielectric Fluids at Different Fe₃O₄ Nanoparticle Concentrations

Abstract

Nano-based dielectric fluids (NDF) seem to be a good alternative for improving dielectric and thermal characteristics of conventional liquid dielectric systems used in power transformers. Fe3Q4 (magnetite) nanoparticles (NP) is one of the most investigated type of NP. Sorne experiments have shown that with its addition to mineral oil (MO) and ester, increases in breakdown voltage (BV) can be achieved applying both AC and DC voltages. This kind of NP have the advantage that can be handled and synthesized safely and easily using a two-steps method. Resides, streamer propagation can be reduced or avoided introducing Fe3Q4 NP in dielectric fluids. These NP act as electronic traps and behave like slow-moving charged particles in the NDF. This behaviour as well as other dielectric characteristics such as resistivity, permittivity and loss tangent, depend on the type, size and concentration of NP. In this work, comparisons and analyses of thermal and dielectric performance ofNDF with different Fe3Q4 NP concentration are made taking into account the evolution and behaviour of streamers. It has been found that temperature in streamer tip, its length and speed depend on the Fe3Q4 NP concentration and the BV is affected because of changes in streamer speed. The most adequate concentration for controlling the streamer has been obtained through simulations and comparisons with experimental results showing good agreement.

Finite Element Based Comparative Analysis of Positive Streamers in Multi Dispersed Nanoparticle Based Transformer Oil

“…DS shows the worst results when the concentration is increased to 40%. The similar study was done numerically by Rodríguez-Serna et al [10].…”

“…Fig. 2 Needle-plane geometry of simulation in TO [5] The boundary conditions for the simulation are set as follows [10]:…”