Abstract: A transformer comprising a core and winding wound around a winding axis extending along a limb of the core, said winding terminating in an axial end surface extending in a direction perpendicular to said winding axis, said transformer comprising a ring comprising magnetic material, said ring being located outside said winding and adjacent to said axial end surface. The ring comprises a set of magnetic metal components, such as magnetic metal sheets, said magnetic metal components being distributed about the winding axis and electrically insulated from each other. The core comprises a yoke, said yoke extending radially across the ring, at one or more crossing locations, from a radial inside of the ring to a radial outside of the ring. The cross-sectional height of the ring varies about the winding axis such that magnetic metal components at the crossing locations have lower height along the winding axis than magnetic metal components further away from the crossing locations.

Abstract: A power transformer, including a core and a winding is provided. The core includes a limb and a yoke. The winding is wound around the limb and has an extension along a main axis of the limb. The power transformer further includes an energy harvesting device coupled to at least one of the core or the winding. The energy harvesting device includes a ferromagnetic part and a coil wound around at least a portion of the ferromagnetic part. The energy harvesting device is arranged in such a way that a part of a magnetic flux MF generated in the power transformer induces an electromotive force in the energy harvesting device. The coil includes a wire wound around a main axis of the coil and has an extension along the main axis of the coil.

Abstract: An electrical device including: voltage carrying components, a solid insulation system configured to electrically insulate the voltage carrying components, and a moisture sensor configured to detect moisture in the solid insulation system, wherein the moisture sensor includes: a capacitor having: a first electrode, a second electrode, and a dielectric material arranged between the first electrode and the second electrode, wherein the solid insulation system forms the dielectric material, the capacitance of the capacitor providing an indication of a moisture level in the dielectric material.

Abstract: An electrical device including: voltage carrying components, a solid insulation system configured to electrically insulate the voltage carrying components, and a moisture sensor configured to detect moisture in the solid insulation system, wherein the moisture sensor includes: a capacitor having: a first electrode, a second electrode, and a dielectric material arranged between the first electrode and the second electrode, wherein the solid insulation system forms the dielectric material, the capacitance of the capacitor providing an indication of a moisture level in the dielectric material.

Abstract: The present invention relates to a static electric induction apparatus (1b) comprising a winding (2) including a plurality of winding units (3), at least one first spacer element (5) arranged between the winding units (3) and including a first groove (18) defined in the surface thereof, and a sensor system for monitoring the temperature in the apparatus, wherein the sensor system comprises an elongated and flexible temperature sensing element (16) disposed in the first groove. The first groove (18) has a curved part that receives the flexible temperature sensing element which is wound at least one revolution in the first groove (18). The first groove enters and exits the first spacer element in one and the same end of the first spacer element. The apparatus comprises an elongated second spacer element (14a) extending in an axial direction on the outside of the winding (2).

Abstract: The present disclosure relates to a cable for a high voltage winding of an electromagnetic induction device. The cable includes a conductor having a width w, and a shield arranged around at least a portion of the conductor, wherein in any cross-section of the conductor the conductor has rounded corners with a radius r in the range w/5<r?w/3. A high voltage electromagnetic induction device having a cable forming a high voltage winding is also disclosed.

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: The present invention relates to a static electric induction apparatus (1b) comprising a winding (2) including a plurality of winding units (3), at least one first spacer element (5) arranged between the winding units (3) and including a first groove (18) defined in the surface thereof, and a sensor system for monitoring the temperature in the apparatus, wherein the sensor system comprises an elongated and flexible temperature sensing element (16) disposed in the first groove. The first groove (18) has a curved part that receives the flexible temperature sensing element which is wound at least one revolution in the first groove (18). The first groove enters and exits the first spacer element in one and the same end of the first spacer element. The apparatus comprises an elongated second spacer element (14a) extending in an axial direction on the outside of the winding (2).

Abstract: The present invention relates to an electrical device comprising a gas-insulated transformer or reactor. The electrical device comprises a housing enclosing an interior space, at least a portion of which defining an insulation space containing a dielectric insulation fluid comprising an organofluorine compound, and an electrical component being arranged in the insulation space and being surrounded by the insulation fluid. The electrical component comprises at least one winding. The electrical device further comprises an electrical connector for bringing the apparatus from non-operational state to operational state by connecting at least one winding to a power grid. The device further comprises an auxiliary power source which is connectable to at least one winding when the apparatus is in the non-operational state.

Abstract: The present disclosure relates to a cable for a high voltage winding of an electromagnetic induction device. The cable includes a conductor having a width w, and a shield arranged around at least a portion of the conductor, wherein in any cross-section of the conductor the conductor has rounded corners with a radius r in the range w/5<r?w/3. A high voltage electromagnetic induction device having a cable forming a high voltage winding is also disclosed.

Abstract: There is provided a transformer core. The transformer core comprises a first yoke and a second yoke. The transformer core comprises at least two limbs extending between the first yoke and the second yoke. The first yoke is of grain-oriented steel. At least one of the second yoke and one of the at least two limbs is of amorphous steel. A method of manufacturing such a transformer core is also disclosed.

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: An electromagnetic induction device including a magnetic core having a limb which has a first end and a second end, windings arranged around the limb, and a housing including magnetic material, which housing defines a space in which the magnetic core and the windings are arranged, wherein the housing defines a return path for the primary magnetic flux, enabling primary magnetic flux from the first end of the limb to flow via the housing to the second end of the limb.

Abstract: The present invention relates to an electrical device comprising a gas-insulated transformer or reactor. The electrical device comprises a housing enclosing an interior space, at least a portion of which defining an insulation space containing a dielectric insulation fluid comprising an organofluorine compound, and an electrical component being arranged in the insulation space and being surrounded by the insulation fluid. The electrical component comprises at least one winding. The electrical device further comprises an electrical connector for bringing the apparatus from non-operational state to operational state by connecting at least one winding to a power grid. The device further comprises an auxiliary power source which is connectable to at least one winding when the apparatus is in the non-operational state.

Abstract: A method of manufacturing a polymer-insulated conductor. The method includes the steps of a) providing a conductor having a first cross-sectional shape, b) passing the conductor through a conductor-shaping die to shape the conductor such that the conductor obtains a second cross-sectional shape, wherein frictional heat is developed in the conductor, thereby setting the conductor in a heated state, c) applying molten polymer to the conductor when the conductor is in the heated state to obtain a polymer-coated conductor, and d) shaping the polymer-coated conductor by means of a polymer-shaping die to thereby obtain the polymer-insulated conductor.

Abstract: An electromagnetic induction device including a magnetic core having a limb which has a first end and a second end, windings arranged around the limb, and a housing including magnetic material, which housing defines a space in which the magnetic core and the windings are arranged, wherein the housing defines a return path for the primary magnetic flux, enabling primary magnetic flux from the first end of the limb to flow via the housing to the second end of the limb.

Abstract: A method of manufacturing a polymer-insulated conductor. The method includes the steps of a) providing a conductor having a first cross-sectional shape, b) passing the conductor through a conductor-shaping die to shape the conductor such that the conductor obtains a second cross-sectional shape, wherein frictional heat is developed in the conductor, thereby setting the conductor in a heated state, c) applying molten polymer to the conductor when the conductor is in the heated state to obtain a polymer-coated conductor, and d) shaping the polymer-coated conductor by means of a polymer-shaping die to thereby obtain the polymer-insulated conductor.

Abstract: A cable for winding of an electromagnetic device. The cable includes a conductor, and a layer including a magnetic material having a relative permeability in the range 2 to 100000, wherein the layer at least partly surrounds the conductor.

Abstract: An electrical bushing for providing electrical insulation of a conductor extending through the bushing is disclosed. The bushing includes: one conductive foil concentrically arranged around the conductor location; and one FGM part, made from a field grading material and partly arranged in the extension of part of a foil edge of a conductive foil. The FGM part and the conductive foil, in the extension of which the FGM part is arranged, are in electrical contact.

Abstract: A cable for winding of an electromagnetic device. The cable includes a conductor, and a layer including a magnetic material having a relative permeability in the range 2 to 100000, wherein the layer at least partly surrounds the conductor.