Study on characteristic gas migration based on a scale-down ascending flanged base

The large oil gap and poor oil circulation in the ascending flanged base of large transformers may lead to difficulty or delay in the migration of fault characteristic gas, making it difficult for the fault to be detected in time by the online or off-line dissolved gas diagnosis technology, which seriously endangers the safe operation of the transformer. Numerical simulation is a practical approach to obtaining the gas migration characteristics in a real high-voltage transformer, in order to verify the simulated results, a scale-down ascending flange base of forced oil circulation transformer is established. The Characteristic gas migration process, is numerically simulated by finite element method considering convection and diffusion. The results are in good consistency with the experimental results, which proves the effectiveness of the simulation method. By comparing the simulation and experimental results, it is found that the convection caused by forced oil circulation and temperature gradient dominates the gas migration. It provides conditions for further research on the gas migration in a real transformer.