A method produces a coil sheet from an initial coil sheet in which a conductor layer, a thermally resistant insulating layer, a thermosetting, uncured adhesive layer, and a base layer are stacked in this order. The method includes a first cutting step of cutting the conductor layer into a predetermined shape through etching, and a second cutting step of cutting, after the first cutting step, the insulating layer and the adhesive layer into the predetermined shape through etching.

A transformer cooling system is described. The transformer cooling system includes a dry transformer and a housing for the dry transformer. The dry transformer includes a core including a leg. Additionally, the dry transformer includes a winding body arranged around the leg. Further, a cooling channel extending in a direction of a longitudinal axis of the winding body is provided. Additionally, the transformer cooling system includes a heat exchanger adapted to dissipate heat from the housing. Further, the transformer cooling system includes a flow generating device arranged in the housing for providing a cooling flow in the cooling channel. The flow generating device is connected to the heat exchanger.

An insulation member for being arranged adjacent to a transformer coil is provided. The insulation member includes a flat base including a first half and a second half defined along a symmetry plane and a plurality of discrete spacers projecting from the plane of the base. The spacers are attached to the first and second halves for allowing a cooling fluid to circulate between the coil and the flat base. The first half includes at least four zones, each zone having spacers arranged according to a predetermined orientation with respect to an orientation axis. The orientation of spacers between adjacent zones is different. The spacers at a first zone are oriented at an angle of between 120-150 degrees, in a second zone at between 80-100 degrees, in a third zone at between 30-60 degrees, and in a fourth zone between 120-150 degrees.

A method for manufacturing an electric winding of an electromagnetic induction apparatus includes providing a conductor structure and forming an electric winding by means of the conductor structure. The conductor structure includes a conductor element extending longitudinally along a main extension direction and one or more spacer bands arranged on corresponding lateral surfaces of the conductor element. Each spacer band includes a supporting structure made of electrically insulating material and spacer elements made of electrically insulating material arranged on the supporting structure. The spacer elements are spaced one from another along the supporting structure. The electric winding extends axially along a winding direction and has a plurality of turns arranged around the winding direction. Each turn of the electric winding is formed by a corresponding longitudinal portion of the conductor element. The spacer elements are interposed between adjacent turns of the electric winding at opposite sides of the turns.

In some embodiments, a cooling device of a power transformer is presented and, more particularly, to a cooling device of a power transformer which may include a heat pipe and a heat sink to improve cooling performance, and to attenuate noise by eliminating a cooling fan.

A winding arrangement for an electric installation has an electric conductor and a plurality of cooling ducts. The electric conductor is coiled up forming several layers around an axis. Each cooling duct extends between a pair of adjacent layers of the coiled electric conductor in axial direction through the winding arrangement and in tangential direction not entirely around the axis. The cooling ducts of the plurality of cooling ducts are distributed among more than one pair of adjacent layers such that the winding arrangement is substantially cylindrical.

A dry-type transformer for mobile applications includes a transformer core, at least one radially inner first winding segment, and at least one radially outer, second hollow cylindrical winding segment. The segments are wound around a common winding axis and the transformer core passes therethrough. The segments are nested inside one another and radially spaced apart from one another, such that a hollow cylindrical cooling duct is formed therebetween. Spacing is achieved by spacer elements arranged such that the cooling duct allows a passage of coolant in an axial direction. The spacer elements are formed and arranged along the radial circumference of the cooling duct over the axial length thereof such that the proportionate weight of the horizontal transformer can be borne on at least one contact surface of the at least second winding segment without causing deformation to the cooling duct.

A multiple parallel conductor that is easy to produce and use and has a plurality of twisted, insulated individual conductors. The individual conductors are arranged above one another in a plurality of sub-conductor bundles arranged next to one another. A strip is applied to the multiple parallel conductor on a side surface of the multiple parallel conductor in the longitudinal direction of the multiple parallel conductor, on which strip spacer plates are arranged so as to be distributed in the longitudinal direction, and the multiple parallel conductor together with the strip and the spacer plates is wrapped with a wrapping.

A non-liquid immersed transformer including a magnetic core having a winding axis and at least two coil windings wound around the magnetic core along the winding axis. One or more cooling tubes made of dielectric material are arranged inside at least one of the coil windings to cool down the coil winding using dielectric fluid flowing through the dielectric cooling tubes. Each cooling tube is wound continuously forming one or more complete loops around the core.

An electric device for connection to a high voltage includes an active part having a magnetizable core and at least one winding arrangement, each surrounding a core section of the core and having windings inductively coupled together, forming cooling channels in the windings. A boiler is filled with insulating fluid and the active part is completely disposed therein. The boiler has at least one insulating fluid inlet and at least one insulating fluid outlet interconnected by a circulation system outside of the boiler having a cooling unit and a pump for circulating the insulating fluid. The electric device has improved cooling achieved by each insulating fluid inlet being connected to a distributing unit, which is disposed on one of the end sides of the winding assembly, via an insulating fluid line extending in the boiler, the distributing unit distributing cooled insulating fluid to the cooling channels.