Patent ID: 8081054

Claim:
A transformer comprising: a housing; a core-winding assembly positioned within the housing and including a transformer core and a plurality of windings wound about the transformer core; a transformer fluid contained within the housing and immersing the core-winding assembly; and a cooling system configured to cool the transformer fluid contained within the housing, the cooling system comprising: a closed-loop fluid path; a quantity of cooling fluid contained within the closed-loop fluid path that is circulated there through; a liquid-to-liquid heat exchanger positioned along the closed-loop fluid path and within the housing so as to be immersed within the transformer fluid, the liquid-to-liquid heat exchanger configured to cool the transformer fluid contained within the housing based on a liquid-to-liquid transfer of heat energy between the cooling fluid and the transformer fluid; and a heat dissipation system positioned remotely from the liquid-to-liquid heat exchanger and configured to cool the cooling fluid circulating through the closed-loop fluid path; wherein the cooling fluid comprises a first dielectric fluid and the transformer fluid comprises a second dielectric fluid, the first dielectric fluid being maintained separate from the second dielectric fluid.