COIL ASSEMBLY AND SUPPORT SYSTEM FOR TRANSFORMER, TRANSFORMER EMPLIYING SAME AND METHOD FOR MANUFACTURE THEREOF

A coil assembly includes a first winding for circumferentially surrounding at least a portion of a leg of a transformer core, a second winding spaced from and circumferentially surrounding at least a portion of the first winding, first supports, such as axially extending insulative rods, disposed between the first and second winding, for inhibiting axial motion of the second winding relative to the first winding and a second support disposed about at least a portion of the outer periphery of the second winding for inhibiting radial motion of the second winding relative to the first winding. Encapsulating material, such as an epoxy resin having glass fibers disposed therethrough, is disposed between the first winding and the leg, between the first and second winding and disposed about the second support for forming a monolithic structure. In a transformer including such a coil assembly, the leg and conductors forming the windings may be fluid cooled. In a method for forming a coil assembly, the encapsulating material is flowed from the bottom of the assembly to fill spaces and to avoid formation of bubbles therein before curing.