Calculation model of arc discharge pressure in transformer oil

Internal short circuit faults in transformers can lead to high-energy arc discharges, resulting in incidents of oil tank rupture, explosion, and fire. The source of transformer explosion accidents is the high-voltage bubbles generated by the gasification and decomposition of transformer oil during high-energy arc discharge. Therefore, studying the mechanism of bubble generation due to arc discharge faults in transformer oil is crucial for understanding the subsequent pressure increase and deformation of the oil tank. In this paper, the evaporation-condensation model is modified to include the chemical reactions of high-temperature decomposed insulating oil. A calculation method based on the modified evaporation-condensation model is proposed to simulate the generation of bubbles in the fluid domain. A three-dimensional simulation model of the oil tank is established to analyze the variation process of bubbles and the pressure changes in the fluid domain after bubble generation. This research provides a reference for studying the mechanism of fault bubble generation in transformer oil and offers a new modeling and calculation method for simulating the change of pressure field during the electric arc discharge process in oil.