Effects of conductive and dielectric nanoparticles on the streamer propagation in transformer oil

Summary

Transformer oil is the most widely used liquid dielectric in power transformers. The breakdown property of transformer oil is directly related to the safety and steady operation of power transformers. It has been demonstrated that adding suitable amount of conductive or dielectric nanoparticles to transformer oil can improve its insulation properties. However, the research in this field is still at a beginning stage and the nano-modification mechanism for insulation properties of transformer oil are not clear yet. The process of streamer propagation determines the breakdown performance of transformer oil. To explore nano-modification mechanism for breakdown properties of transformer oil, it is necessary to investigate the nanoparticle effects on the streamer propagation in transformer oil. In this study, the finite element method was utilized to model the streamer initiation and propagation process in pure transformer oil and two types of transformer oil based nanofluids modified by Fe3O4 nanoparticles and Al2O3 nanoparticles. Simulation results indicate that the streamer propagations in nanofluids are hindered and the space charge densities in streamer channel are increased. Fe3O4-modiefied nanofluid is more affected by nano-modification due to the stronger electron adsorption capacity of Fe3O4 nanoparticles than that of Al2O3 nanoparticles.

Additional informations

Authors

LEBER, JIA, ZAJÍC, HOLSTEIN, JONES

Keywords

Transformer oil, Breakdown, Nanoparticles, Streamer propagation