Abstract: A three-phase stacked triangular transformer core is provided. The transformer has three legs and six yoke parts therebetween, wherein the legs include stacked laminations. In a cross-sectional plane perpendicular to a central transformer core axis, the stacked laminations are oriented in substantially radial direction, and each leg has two leg halves, wherein each leg half has a plurality of outer corners facing a corresponding leg half of a neighboring leg. For each of the leg halves the plurality of outer corners lie on a respective straight line within a lateral tolerance, and for each leg half the straight line defined by this leg half and the straight line defined by the corresponding leg half of the neighboring leg are parallel.

Abstract: A method for manufacturing a stacked triangular core transformer includes assembling a triangular core by positioning of two halves of one leg on an assembly stand in the horizontal position; securing the positioned halves; positioning an outer clamping beam underneath two leg halves at the one end of the leg halves; assembling a yoke segment at the one end of two halves of the core leg; and forming a first clamp of the frame. The method continues by forming a second clamp of the frame at the other end of the two halves of the core leg by repeating the above positioning, assembling and forming steps; tightening the clamps together by securing means; rotating a single core frame into vertical position and releasing securing bar of the assembly stand; assembling two additional single core frames by repeating the above steps; positioning the frames in abutting position, and tightening them together.

Abstract: A three-phase stacked triangular transformer core is provided. The transformer has three legs and six yoke parts therebetween, wherein the legs include stacked laminations. In a cross-sectional plane perpendicular to a central transformer core axis, the stacked laminations are oriented in substantially radial direction, and each leg has two leg halves, wherein each leg half has a plurality of outer corners facing a corresponding leg half of a neighboring leg. For each of the leg halves the plurality of outer corners lie on a respective straight line within a lateral tolerance, and for each leg half the straight line defined by this leg half and the straight line defined by the corresponding leg half of the neighboring leg are parallel.

Abstract: A preferred method for manufacturing a transformer winding includes winding an electrical conductor into a first plurality of turns, placing an electrically insulating material having adhesive thereon over the first plurality of turns, and winding the electrical conductor into a second plurality of turns over the electrically insulating material. The preferred method also includes melting and curing the adhesive by energizing the electrical conductor so that a current greater than a rated current of the transformer winding flows through the electrical conductor.

Abstract: A preferred embodiment of a three-phase transformer includes a first, a second, and a third winding leg, and a first, a second, and a third winding positioned around the respective first, second, and third winding legs. The first, second, and third windings each includes an electrical conductor wound into a plurality of overlapping layers each formed by a plurality of adjacent turns of the electrical conductor, and an insulating material without end fill positioned between each of the overlapping layers. The electrical conductor has a transition portion formed therein between a first and a second of the overlapping layers. The transition portion is at least one of bent to form an offset in the electrical conductor, and secured to at least one of the plurality of adjacent turns.

Abstract: A preferred method for forming a transformer winding includes providing a length of copper wire having a substantially circular cross section, flattening the length of copper wire in two dimensions on a substantially simultaneous basis, and winding the length of copper wire into a first layer of adjacent turns.

Abstract: A preferred method for manufacturing a transformer winding includes winding an electrical conductor into a first plurality of turns, placing an electrically insulating material having adhesive thereon over the first plurality of turns, and winding the electrical conductor into a second plurality of turns over the electrically insulating material. The preferred method also includes melting and curing the adhesive by energizing the electrical conductor so that a current greater than a rated current of the transformer winding flows through the electrical conductor.

Abstract: A preferred embodiment of a three-phase transformer includes a first, a second, and a third winding leg, and a first, a second, and a third winding positioned around the respective first, second, and third winding legs. The first, second, and third windings each includes an electrical conductor wound into a plurality of overlapping layers each formed by a plurality of adjacent turns of the electrical conductor, and an insulating material without end fill positioned between each of the overlapping layers. The electrical conductor has a transition portion formed therein between a first and a second of the overlapping layers. The transition portion is at least one of bent to form an offset in the electrical conductor, and secured to at least one of the plurality of adjacent turns.