Modeling and Test Characterization of Fault Pressure Characteristics within Transformer Tanks

Transformer internal faults seriously threaten the safe operation of transformers. This study aims to explore the transformer tank internal fault pressure characteristics modeling and test characteristics, revealing the development and change rule of pressure wave, for the tank explosion-proof design to provide simulation platform and theoretical support. First of all, the transformer tank internal fault modeling, the use of finite element analysis method to calculate the pressure wave propagation caused by the transient process of pressure increase in the tank; Secondly, build a high-voltage impulse discharge oil breakdown experimental platform to capture the arc discharge pressure wave propagation process in the oil. The results show that: when the discharge gap is small, the experimental results are consistent with the simulation results, and the fault point can be equated to a sphere, the pressure wave spreads in all directions at the speed of sound or supersonic speed, and the closer the measurement point is to the fault point, the greater the pressure; in the case of a long discharge gap, in fact, the pressure wave is not a standard sphere, but it can be equated to half of it as the superposition of two ellipsoids, and the other half of it as a standard ellipsoid, and the pressure wave is not the same as the traditional pressure shock source model, but it is not the same as that in the conventional pressure shock source model. It is inconsistent with the results of traditional pressure seismic source modeling. This study provides a new experimental basis for the pressure wave morphology change of arc discharge in oil, which is an important reference value for the refined transformer deformation rupture modeling.