Gas cooling performance in disc winding of large-capacity gas-insulated transformer

We have developed the gas-cooling system of a 275 kV, 300 MVA class gas-insulated transformer. In our study model experiments in which gas flow was substituted by water flow equivalently and 2-dimensional numerical flow analyses and network analyses were conducted. In this paper the outline of the development and optimization condition to get high cooling performance in SF6 gas-disc winding system of the transformer are presented.