Abstract: A high voltage winding for a single electrical phase of a high voltage electromagnetic induction device, wherein the high voltage winding comprises: a first winding part, and a second winding part, wherein the first winding part comprises: a first conductor, a first solid electrical insulator circumferentially enclosing the first conductor, and a first semi-conductive sheath circumferentially enclosing the first solid electrical insulator, wherein the first semi-conductive sheath is earthed or connected to an electric potential that is lower than a rated voltage of the high voltage winding, and wherein the second winding part comprises: a second conductor, and a second solid electrical insulator circumferentially enclosing the second conductor and forming an outermost layer of the second winding part.

Abstract: A high voltage winding for a single electrical phase of a high voltage electromagnetic induction device, wherein the high voltage winding comprises: a first winding part, and a second winding part, wherein the first winding part comprises: a first conductor, a first solid electrical insulator circumferentially enclosing the first conductor, and a first semi-conductive sheath circumferentially enclosing the first solid electrical insulator, wherein the first semi-conductive sheath is earthed or connected to an electric potential that is lower than a rated voltage of the high voltage winding, and wherein the second winding part comprises: a second conductor, and a second solid electrical insulator circumferentially enclosing the second conductor and forming an outermost layer of the second winding part.

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.