Simulation Analysis of Oil Velocity Features under Internal Arc Discharge Conditions in Transformer

This paper presents a simulation analysis of oil velocity characteristics under internal arc discharge conditions in transformers, supported by experimental validation. When an arc discharge occurs, the insulating oil at the fault point vaporizes, forming high-pressure bubbles that induce significant pressure differences, causing fluid flow. The study models this effect by calculating arc energy, establishing the relationship between fault energy and gas production, and simulating the resulting pressure and flow velocity changes. A three-dimensional model of a 110 kV oil-immersed transformer was developed to simulate flow velocity distribution during are discharges. The simulation results were verified through experiments, which involved measuring oil flow velocities at four monitoring points. The experimental data closely matched the simulation predictions, confirming the reliability of the model. This work demonstrates the potential for using oil flow velocity changes to detect transformer faults and provides insights into transformer fault diagnosis.