Short-circuit discharge inside ultra high voltage transformers can cause decomposition of transformer oil and gas generation

leading to an increase in pressure inside the tank

resulting in tank rupture or even explosion. It is urgent to conduct research on the pressure characteristics during arcing. However

the pressure waveform inside the oil tank during arcing is intricate

and the limited understanding of the patterns and influencing factors of the pressure waveform has constrained research on arcing pressure. In this paper

by establishing electric arc discharge experimental platform within a sealed tank

the dynamic pressure characteristics during discharge in transformer oil are investigated. Segmented pressure waveform characteristics under power-frequency arc discharge conditions are obtained. The experimental results show that under power frequency current

the dynamic pressure waveform induced by arc discharge in a sealed filled oil tank is divided into four stages: shock wave

bubble pulsation pressure

quasi-static pressure

and steady pressure. The gas-liquid-solid coupling process is an important generation mechanism for dynamic pressure in the tank. This study reveals the segmented characteristics and waveform patterns of discharge pressure

providing reference for understanding and simulating the pressure characteristics with arc in transformer oil tanks.