Investigating Positive Streamer Dynamics in Transformer Oil based Hybrid Nanofluids

Abstract

newlinePower transformer is one of the most important electrical equipment for providing reliable newlinepower flow that contributes to the highest capital investments for an electric utility in project newlineexecutions. Hence, it is important to ensure the safety of the transformer during its operation. newlineThe healthy and reliable operation of power transformer primarily relies on an effective newlineinsulation system. Overloading, high operating temperatures, lightning or switching surges, newlineand incorrect lubrication are some of the variables that affect the life expectancy of insulation newlinein a transformer. newlineMineral oil is the most important element of the transformer that provides the reliability and newlinesafety against the transient overvoltages and enhances the service lifespan of power newlinetransformers. Furthermore, because of the transformer s oxidation sensitivity, the oil helps in newlinepreventing direct contact with ambient oxygen. The structure of mineral oil, on the other hand, newlineis highly complicated as it containing a wide spectrum of molecular impurities of sulphur, newlineoxygen, and nitrogen molecules. The polycyclic aromatic hydrocarbons diluted in it may newlineexplode the transformer when subjected to intensive thermal, mechanical and electrical newlinestresses. As a result, many methodologies, preventative and reactive maintenance, and newlinerepair procedures have been developed to eliminate or reduce the likelihood of failures and newlinebreakdowns. newlineThe pre-breakdown stages of liquid dielectrics involve the generation and propagation of newlinestreamer discharge, which is a complex phenomenon. The presence of sparking channels newlineleads to catastrophic failure of the transformers due to the involvement of rapid ionization newlineunder heavy electrical, mechanical, and thermal stresses. The fast propagating positive newlinestreamers are considered to be more severe than slowly developed negative streamers. The newlinenanoparticle suspensions have capacity to resist the development of positive streamers and newlineimproves the dielectric strength of transformer oil. newlinevi newlineThe nanoparticles act as scatterin