EP4625450A1 - Winding, transformer, method of manufacturing a winding of a transformer, and method of operating a dry-type transformer - Google Patents

Winding, transformer, method of manufacturing a winding of a transformer, and method of operating a dry-type transformer

Info

Publication number
EP4625450A1
EP4625450A1 EP24382339.0A EP24382339A EP4625450A1 EP 4625450 A1 EP4625450 A1 EP 4625450A1 EP 24382339 A EP24382339 A EP 24382339A EP 4625450 A1 EP4625450 A1 EP 4625450A1
Authority
EP
European Patent Office
Prior art keywords
winding
cooling medium
cooling
transformer
winding portion
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Pending
Application number
EP24382339.0A
Other languages
German (de)
French (fr)
Inventor
Rafael MURILLO JASO
Antonio Nogues Barrieras
Lorena Cebrian Lles
Carlos Manuel ROY MARTIN
Alfredo DE LA VEGA-HAZAS ALVAREZ-BARON
Vito MURGIDA
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Hitachi Energy Ltd
Original Assignee
Hitachi Energy Ltd
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Hitachi Energy Ltd filed Critical Hitachi Energy Ltd
Priority to EP24382339.0A priority Critical patent/EP4625450A1/en
Priority to PCT/EP2025/058582 priority patent/WO2025202467A1/en
Publication of EP4625450A1 publication Critical patent/EP4625450A1/en
Pending legal-status Critical Current

Links

Classifications

    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01F—MAGNETS; INDUCTANCES; TRANSFORMERS; SELECTION OF MATERIALS FOR THEIR MAGNETIC PROPERTIES
    • H01F27/00—Details of transformers or inductances, in general
    • H01F27/08—Cooling; Ventilating
    • H01F27/085—Cooling by ambient air
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01F—MAGNETS; INDUCTANCES; TRANSFORMERS; SELECTION OF MATERIALS FOR THEIR MAGNETIC PROPERTIES
    • H01F27/00—Details of transformers or inductances, in general
    • H01F27/08—Cooling; Ventilating
    • H01F27/20—Cooling by special gases or non-ambient air
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01F—MAGNETS; INDUCTANCES; TRANSFORMERS; SELECTION OF MATERIALS FOR THEIR MAGNETIC PROPERTIES
    • H01F27/00—Details of transformers or inductances, in general
    • H01F27/28—Coils; Windings; Conductive connections
    • H01F27/32—Insulating of coils, windings, or parts thereof
    • H01F27/322—Insulating of coils, windings, or parts thereof the insulation forming channels for circulation of the fluid
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01F—MAGNETS; INDUCTANCES; TRANSFORMERS; SELECTION OF MATERIALS FOR THEIR MAGNETIC PROPERTIES
    • H01F27/00—Details of transformers or inductances, in general
    • H01F27/28—Coils; Windings; Conductive connections
    • H01F27/32—Insulating of coils, windings, or parts thereof
    • H01F27/327—Encapsulating or impregnating
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01F—MAGNETS; INDUCTANCES; TRANSFORMERS; SELECTION OF MATERIALS FOR THEIR MAGNETIC PROPERTIES
    • H01F41/00—Apparatus or processes specially adapted for manufacturing or assembling magnets, inductances or transformers; Apparatus or processes specially adapted for manufacturing materials characterised by their magnetic properties
    • H01F41/02—Apparatus or processes specially adapted for manufacturing or assembling magnets, inductances or transformers; Apparatus or processes specially adapted for manufacturing materials characterised by their magnetic properties for manufacturing cores, coils, or magnets
    • H01F41/04—Apparatus or processes specially adapted for manufacturing or assembling magnets, inductances or transformers; Apparatus or processes specially adapted for manufacturing materials characterised by their magnetic properties for manufacturing cores, coils, or magnets for manufacturing coils
    • H01F41/12—Insulating of windings
    • H01F41/127—Encapsulating or impregnating
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01F—MAGNETS; INDUCTANCES; TRANSFORMERS; SELECTION OF MATERIALS FOR THEIR MAGNETIC PROPERTIES
    • H01F27/00—Details of transformers or inductances, in general
    • H01F27/28—Coils; Windings; Conductive connections
    • H01F27/32—Insulating of coils, windings, or parts thereof
    • H01F27/327—Encapsulating or impregnating
    • H01F2027/328—Dry-type transformer with encapsulated foil winding, e.g. windings coaxially arranged on core legs with spacers for cooling and with three phases

Definitions

  • Transformers are widely used to convert electricity from a first voltage level to a second voltage level, the second voltage level being either higher or lower than the first voltage level.
  • Transformers generate heat during operation, in particular due to a power loss dissipated by the transformer in the form of heat.
  • a power loss of the transformer comprises core losses and winding or coil losses.
  • the core and the windings of the transformer generate heat within the transformer, which should be transferred away from the transformer to achieve a better performance, a longer lifetime of the transformer, and lower operational costs of the transformer.
  • Transformers having such a configuration are often referred to as liquid or oil filled transformers.
  • a gas such as air
  • a gas such as air
  • a pressure drop of the flow of cooling medium, i.e., in particular a cooling gas, through the respective cooling channel is relatively large in at least some of the prior art transformers. This may reduce the velocity of the flow of cooling medium and/or may require a larger pressure at an entrance of the cooling channel to achieve the desired and/or target velocity or mass flow of cooling medium, e.g., by using a larger blower and/or by providing more power to the respective blower.
  • a position and/or an orientation of the respective cooling channel in the transformer and/or winding of at least some of the prior art transformers may be disadvantageous to a cooling system of the respective transformer which includes the cooling channels, in particular the construction and/or the arrangement of one or more further components of the cooling system, of the respective transformer.
  • an arrangement of one or more further components of the cooling system may negatively affect the one or more functions and/or the operation of the transformer.
  • the winding may be a winding of a dry-type transformer.
  • the winding may be configured to be arranged to at least partially surround at least one core of the transformer.
  • the winding may include a plurality of gaps defined at least partially between adjacent winding portions of the plurality of winding portions, in particular between winding portions which are adjacent to each in a direction along a longitudinal axis of the transformer and/or a longitudinal axis of the core and/or a winding axis of one of more of the winding portions.
  • the winding may include a first gap which may be arranged at least partially between two adjacent winding portions, e.g., between the first winding portion and the second winding portion.
  • the first gap may be at least partially filled with electrically insulating material.
  • the winding may include any number of winding portions.
  • the winding may include at least two winding portions, at least three winding portions, etc.
  • the winding may include more than three winding portions.
  • a gap may be arranged between two sequential and/or adjacent winding portions. At least one of the cooling channels may be arranged at least partially in each of the gaps.
  • the electrically conductive material may have any cross-sectional shape, e.g., round, oval, rectangular, etc.
  • the winding portions i.e., the first winding portion, second winding portion, the third winding portion, and optionally one or more further winding portions, are preferably arranged in a stacked manner, in particular along a longitudinal axis of the transformer and/or a longitudinal axis of the core and/or along a winding axis of one or more of the winding portions.
  • the first gap and the second gap are preferably spaced apart from each other along a longitudinal axis of the transformer and/or a longitudinal axis of the core and/or along a winding axis of one or more of the winding portions.
  • the winding portions may be connected, in particular electrically connected, in particular by means of at least one interconnecting element, e.g., at least one bar, at least one wire, etc.
  • the interconnecting element may not be wound, e.g., about a winding axis of one or more of the winding portions.
  • the interconnecting element may also include an electrically conductive material, the interconnecting element may be distinguished from the winding portions by one or more features. In particular, the interconnecting element may interrupt and/or alter a winding pattern and/or a winding shape of the respective winding portion.
  • the interconnecting element may extend in an axial direction along a longitudinal axis of the transformer and/or a longitudinal axis of the core and/or along a winding axis of the first winding portion, the second winding portion, and/or the third winding portion at a different angle than the winding portions.
  • the interconnecting element may have a different shape, e.g., a different cross-sectional shape, and/or one or more different dimensions, e.g., one of more different dimensions in a cross-section of the interconnecting element, than the winding portions.
  • the side wall of the winding and/or the transformer in which the cooling medium inlets and the cooling medium outlets are defined within the meaning of the present disclosure, may be a side wall which extends substantially along a longitudinal axis of the transformer and/or a longitudinal axis of the core and/or along a winding axis of one or more of the winding portions.
  • a top side and/or a bottom side, e.g., of the winding, may be connected to the side wall.
  • the side wall may be a side wall defined by the electrically insulating material.
  • the cooling medium inlets may be inlets into the electrically insulating material and the cooling medium outlets may be outlets which exit the electrically insulating material.
  • the cooling medium inlets may be arranged and/or defined by the side wall of the electrically insulating material, e.g., the epoxy resin.
  • the cooling channels may be at least partially, preferably completely, embedded or encapsulated in the electrically insulating material, e.g., by a casting process.
  • At least some of the cooling channels may be fluidically interconnected, in particular at one or more sections downstream of the respective cooling medium inlet. At least some of the cooling channels may share at least one cooling medium inlet and/or at least one cooling medium outlet, as described further below in more detail.
  • the cooling medium inlets and/or the cooling medium outlets are arranged such that the cooling medium can enter the cooling channel via the cooling medium inlets and/or can exit the cooling channel via the cooling medium outlets substantially radially with respect to a circumference of the winding and/or substantially perpendicularly to a longitudinal axis of the winding and/or the transformer and/or the core and/or substantially perpendicularly to a winding axis of the first winding portion and the second winding portion, when the winding is operatively installed in the transformer.
  • This may facilitate a connection to the cooling medium inlets and/or the cooling medium outlets, e.g., a connection of one or more conduits and/or one or more further components of a cooling system, e.g., a cooling medium supply device, to the cooling medium inlets and/or the cooling medium outlets.
  • a connection to the cooling medium inlets and/or the cooling medium outlets e.g., a connection of one or more conduits and/or one or more further components of a cooling system, e.g., a cooling medium supply device, to the cooling medium inlets and/or the cooling medium outlets.
  • the cooling medium inlets and the cooling medium outlets are arranged in a section of the side wall of the transformer and/or a side wall of the winding which is substantially flat. This may facilitate connecting a cooling system and/or a cooling circuit and/or a conduit to the cooling medium inlets and the cooling medium outlets and/or may reduce a risk of leakage at the cooling medium inlets and/or the cooling medium outlets, i.e., at the above-mentioned connection(s).
  • the cooling medium inlets and the cooling medium outlets are arranged in a dome structure of the side wall of the winding.
  • the dome structure may extend from a body of the winding, in particular in a protrusion-like manner.
  • the first cooling channel and the second cooling channel are part of and/or are connected to an open cooling circuit.
  • An "open cooling circuit" within the meaning of the present disclosure, means a non-circulating circuit, i.e., the cooling medium is not refed from the cooling medium outlet to the cooling medium inlet.
  • the winding is configured to introduce ambient air (as the "cooling medium") into the cooling channels via the cooling medium inlets and discharge the ambient air, which has absorbed heat from the transformer, to the ambient via the cooling medium outlets. This may simplify the construction of the winding and/or the transformer, e.g., by being able to omit an external heat exchanger.
  • a plane which extends substantially perpendicularly to a longitudinal axis of the winding and/or the transformer and/or the core and/or substantially perpendicularly to a winding axis of the first winding portion and the second winding portion, when the winding is operatively installed in the transformer, extends through the cooling medium inlet and the cooling medium outlet of the first cooling channel or the cooling medium inlet and the cooling medium outlet of the second cooling channel.
  • the plane may be referred to as a horizontal plane.
  • the plane may facilitate connecting a cooling system and/or a cooling circuit and/or a conduit to the cooling medium inlets and the cooling medium outlets and/or may reduce a risk of leakage at the cooling medium inlets and/or the cooling medium outlets, i.e., at the above-mentioned connection(s).
  • the plane extends through a center of the cooling medium inlet and a center of the cooling medium outlet.
  • the plane extends through the entire first cooling channel or the entire second cooling channel.
  • At least one gap is arranged at least partially between each pair of adjacent winding portions of the winding and at least one of the plurality of cooling channels is arranged at least partially within each gap and the respective cooling medium inlet and cooling medium outlet of the respective cooling channel are arranged in a side wall of the transformer and/or a side wall of the winding.
  • the cooling medium inlets and the cooling medium outlets are arranged such that the cooling medium can enter the respective cooling channel via the cooling medium inlets and the cooling mediums can exit the respective cooling channel via the cooling medium outlets in substantially opposite directions.
  • This may allow the respective cooling medium inlet(s) and the cooling medium outlet(s) of the respective cooling channel to be arranged relatively close to each other, e.g., on the same side and/or the same region of the transformer and/or the winding.
  • the cooling channels are spaced apart from each other along a longitudinal axis of the winding and/or the transformer and/or the core, when the winding is operatively installed in the transformer.
  • at least some of the electrically insulating material may be arranged between the cooling channels, in particular between adjacent cooling channels.
  • At least some of the cooling channels, preferably all of the cooling channels may extend substantially parallel to each other.
  • a first plane which extends through one cooling channel, e.g., the first cooling channel, of the cooling channels may be parallel to a second plane which extends through another cooling channel, e.g., the second cooling channel, of the cooling channels, preferably an adjacent cooling channel.
  • the winding further includes at least one cooling medium supply device configured to supply and distribute the cooling medium to each of the cooling medium inlets.
  • the cooling medium supply device includes a cooling medium supply device inlet, preferably a single cooling medium supply device inlet, which is fluidically connected or fluidically connectable to each cooling medium inlet. Providing the above-described cooling medium supply device may facilitate operation of the cooling of the transformer and/or assembly and/or disassembly of the transformer.
  • the winding may further include at least one cooling medium outlet device configured to collect and guide the cooling medium from each of the cooling medium outlets.
  • the cooling medium outlet device may include a cooling medium outlet device exit, preferably a single cooling medium outlet device exit, which is fluidically connected or fluidically connectable to each cooling medium outlet.
  • the cooling medium supply device and/or the cooling medium outlet device may each be configured as an air box or a manifold.
  • each of the plurality of cooling channels includes a cooling medium inlet for introducing a cooling medium into the cooling channel and/or a cooling medium outlet for allowing the cooling medium to exit from the cooling channel.
  • each cooling channel may have its own cooling medium inlet and/or cooling medium outlet. This may allow a greater mass flow of the cooling medium to be achieved and/or may reduce a pressure loss of the cooling medium at the cooling medium inlets and/or the cooling medium outlets.
  • At least two of the plurality of cooling channels may include a common cooling medium inlet for introducing a cooling medium into the at least two of the plurality of cooling channels and/or a common cooling medium outlet for allowing the cooling medium to exit from the at least two of the plurality of cooling channels. This may reduce a number of fluidical connections to the cooling channels and/or may reduce a risk of leakage at the cooling medium inlets and/or the cooling medium outlets.
  • the cooling channels include one or more partitioning elements configured to segment a cross-sectional area of the respective cooling channel(s) into two or more partitions, preferably three or more partitions.
  • the one or more partitioning elements may allow the flow of cooling medium to be manipulated and/or enhanced, e.g., by altering a shape and/or one or more dimensions of the respective cooling channel(s). In addition, this may allow the flow of cooling medium to be guided more precisely. Moreover, this may allow turbulence in the flow of the cooling medium to be reduced and/or increased, e.g., to reduce flow separation and/or improve the properties of a boundary layer of the cooling medium in the respective cooling channel(s). This may improve the cooling efficiency and/or effectiveness.
  • the one or more partitioning elements may provide a mechanical reinforcement to the respective cooling channel(s), e.g., to increase the stability of the respective cooling channel(s).
  • the partitions extend substantially parallel to each other and/or coaxially and/or are arranged side-by-side. Alternatively, the partitions may extend at different angles to each other.
  • At least a section of the cooling channels extends annularly or semi-annularly along at least a section of the winding.
  • the cooling channels may be curved in at least a section thereof. This may allow the cooling channels to cover a relatively large portion of the winding to absorb heat from a relatively large portion of the winding.
  • the cooling channels, of which at least a section extends annularly or semi-annularly along at least a section of the winding may extend in any shape, e.g., in a circular shape, an oval shape, or a rectangular shape.
  • the term "annularly” or “semi-annularly” does not limit the shape of the cooling channel to a circular shape.
  • the winding includes at least one pipe having a lumen which defines and/or is the respective cooling channel.
  • the pipe is at least partially embedded in the electrically insulating material.
  • the pipe may be made of plastic. Alternatively, or additionally, the pipe may be made a 3D printed component.
  • the pipe is made of an electrically insulating material, e.g., epoxy resin.
  • the pipe is flexible and/or bendable, in a state of the pipe before assembly of the winding. This may facilitate a process of manufacturing the winding and/or the transformer, in particular of providing or integrating the cooling channels in the winding, more specifically in the electrically insulating material.
  • At least some of the cooling channels are configured to redirect the cooling medium by at least 90°, preferably at least 120°, more preferably at least 150°, more preferably at least 180°, more preferably at least 210°, more preferably at least 240°, more preferably at least 270°, more preferably at least 300°, more preferably at least 330°, more preferably by 360°.
  • the angle(s) mentioned above may be understood as an angle between a direction in which the cooling medium inlet of the respective cooling channel faces and/or is directed and a direction in which the cooling medium outlet of the respective cooling channel faces and/or is directed, i.e., such that an angle of 360° may mean that the cooling medium inlet and the cooling medium outlet of the respective cooling channel are directed and/or face in substantially the same direction. This may allow the cooling channels to cover a relatively large portion of the winding to absorb heat from a relatively large portion of the winding.
  • At least some of the cooling channels are configured to guide the cooling medium about at least 50%, preferably at least 60%, more preferably at least 70%, more preferably at least 80%, more preferably at least 90%, of a circumference of the core of the transformer, when the winding is operatively installed in the transformer.
  • the winding further includes at least one flow generating device which can be powered, preferably electrically, to generate a forced convection flow of the cooling medium through the cooling channels.
  • at least one flow generating device which can be powered, preferably electrically, to generate a forced convection flow of the cooling medium through the cooling channels.
  • the first winding portion, the second winding portion, and the third winding portion are stacked along a longitudinal axis of the transformer and/or a longitudinal axis of the core and/or along a winding axis of the first winding portion, the second winding portion, and/or the third winding portion.
  • the present disclosure also relates to a transformer which may include at least one core and at least one winding, preferably at least one winding according to any of the embodiments described herein, which at least partially surrounds the core.
  • the transformer further includes at least one flow generating device, preferably at least one flow generating device which can be powered, preferably electrically, to generate a forced convection flow of the cooling medium through the cooling channels.
  • the flow generating device may be configured and arranged to force, i.e., blow or push, the cooling medium, e.g., air, into the cooling medium inlets.
  • the flow generating device may be arranged upstream from the cooling medium inlets.
  • the transformer may include at least one flow generating device, e.g., the flow generating device mentioned above or a further flow generating device, which is configured and arranged to suck the cooling medium, e.g., air, out of the cooling medium outlets.
  • the flow generating device may be arranged downstream from the cooling medium outlets.
  • the flow of cooling medium may be caused by natural convection only.
  • the transformer is free of a radiator.
  • a "radiator”, within the context of the present disclosure, means a heat exchanging device in addition to the cooling channels provided in the winding and in a narrower sense, i.e., a heat exchanging device whose only or at least primary function is to exchange heat, e.g., a shell and tube heat exchanger, etc.
  • the transformer may be free of a radiator which is arranged externally of the winding.
  • the cooling channels may not be connected to a radiator. Instead, for instance, the cooling channels may be part of an opening cooling circuit (as mentioned above).
  • the cooling medium may be drawn into the cooling medium inlets from the ambient and/or environment and/or at ambient conditions, i.e., the cooling medium may be drawn from the ambient and/or environment without prior conditioning, in particular cooling, and the cooling medium may be discharged into the ambient and/or environment.
  • the winding may be configured to be arranged to at least partially surround a core of the transformer.
  • the method may include: arranging a first winding portion which includes an electrically conductive material.
  • the method may include: arranging a second winding portion which includes an electrically conductive material such that a first gap is arranged at last partially between the first winding portion and the second winding portion.
  • the method may include:
  • the method may include: providing a plurality of cooling channels configured to guide at least one cooling medium therethrough to transfer heat from the transformer to the cooling medium.
  • the plurality of cooling channels may include a first cooling channel arranged within the first gap and at least a second cooling channel arranged within the second gap.
  • the first cooling channel and the second cooling channel may each include at least one cooling medium inlet for introducing the cooling medium into the respective cooling channel and at least one cooling medium outlet for allowing the cooling medium to exit from the respective cooling channel.
  • the cooling medium inlets and the cooling medium outlets may be arranged in a side wall of the transformer.
  • the cooling channels are provided by arranging at least one pipe, preferably a plurality of pipes, at least partially in the respective gap and embedding the pipe(s) least partially in the electrically insulating material.
  • the pipe(s) preferably has/have a lumen which defines and/or is the respective cooling channel.
  • a transformer preferably a dry-type transformer, preferably the transformer according to any of the embodiments described herein.
  • the features, embodiments, and advantages, as detailed herein with respect to the winding, apply to the method accordingly.
  • the winding may include and a plurality of cooling channels configured to guide at least one cooling medium therethrough to transfer heat from the transformer to the cooling medium.
  • the plurality of cooling channels may include a first cooling channel arranged within the first gap and at least a second cooling channel arranged within the second gap.
  • the method may include: introducing the cooling medium into the first cooling channel through at least one cooling medium inlet of the first cooling channel and into the second cooling channel through at least one cooling medium inlet of the second cooling channel.
  • the cooling medium inlets may be arranged in a side wall of the transformer and/or a side wall of the winding.
  • the method may include: discharging the cooling medium from the first cooling channel through at least one cooling medium outlet of the first cooling channel and from the second cooling channel through at least one cooling medium outlet of the second cooling channel.
  • the cooling medium outlets may be arranged in a side wall of the transformer and/or a side wall of the winding.
  • Figs. 1 to 4 schematically show a winding 10 of a transformer, in particular a dry-type transformer.
  • the winding 10 may be configured to be arranged to at least partially surround a core of the transformer.
  • Fig. 1 shows a longitudinal cross-sectional view of the winding 10, i.e., a view of a cut of the winding 10 along a longitudinal axis of the winding 10.
  • Fig. 2 shows a view of a cross-section of the winding 10 which is substantially perpendicular to the longitudinal axis of the winding 10.
  • Fig. 3 shows a front view of the winding 10 and
  • Fig. 4 shows a side view of the winding 10.
  • the longitudinal axis of the winding 10 is shown in Fig. 2 (indicated as "LA"), which extends into and out of the drawing plane based on the illustration in Fig. 2 , and in Figs. 3 and 4 .
  • the longitudinal axis LA of the winding 10 may coincide with the longitudinal axis of the transformer.
  • the winding 10 may include a plurality of winding portions 16 which each include an electrically conductive material.
  • the plurality of winding portions 16 may include a first winding portion 16A, a second winding portion 16B, and a third winding portion 16C.
  • the number of winding portions 16 is only an example.
  • the winding 10 may have less or more winding portions 16 than shown in the Figures.
  • the winding portions 16 may each be wound about a winding axis WA.
  • the winding axis WA may coincide with the longitudinal axis LA of the winding 10 and/or the longitudinal axis of the transformer, as shown in the Figures.
  • the winding axis WA may not coincide with the longitudinal axis LA.
  • the winding axis WA may extend parallel or at an angle to the longitudinal axis LA.
  • the winding 10 may include one or more gaps 20 which are arranged at least partially between at least two of the winding portions 16.
  • a first gap 20A may be arranged between the first winding portion 16A and the second winding portion 16B, as shown in Fig. 1 .
  • the one or more gaps 20 may include at least a second gap 20B which may be arranged at least partially between at least two of the winding portions 16, e.g., between the second winding portion 16B and the third winding portion 16C.
  • the one or more gaps 20, e.g., the first gap 20A and/or the second gap 20B may be at least partially filled with electrically insulating material 22.
  • the winding 10 may include a plurality of channels 24, preferably a plurality of cooling channels 24, which may be configured to guide at least one cooling medium therethrough to transfer heat from the transformer, more specifically the winding 10, to the cooling medium.
  • the plurality of cooling channels 24 may include a first cooling channel 24A which may be arranged within one of the gaps 20, e.g., within the first gap 20A, and at least a second cooling channel 24B which may be arranged within a further gap of the gaps 20, e.g., within the second gap 20B.
  • the cooling medium is preferably a gas, preferably air, preferably ambient air.
  • the winding 10 may include any number of cooling channels 24.
  • the number of cooling channels 24 described herein and shown in the Figures is only exemplary.
  • the winding 10 may include more or less than the number of cooling channels 24 described herein and/or shown in the Figures.
  • the plurality of cooling channels 24 may include one or more cooling channels which are not arranged within a gap between winding portions. For instance, as shown in Fig. 1 , at least one cooling channel 24C of the plurality of cooling channels 24 may be arranged below a lowermost winding portion 16C or above an uppermost winding portion. Alternatively, or additionally, at least one cooling channel of the plurality of cooling channels 24 may be arranged along a side of one or more of the winding portions 16 (not shown).
  • At least a section of the cooling channels 24 may extend annularly or semi-annularly along at least a section of the winding 10, as shown in Fig. 2 .
  • At least some of the cooling channels 24, e.g., the first cooling channel 24A and the second cooling channel 24B, may each include at least one cooling medium inlet 28 for introducing the cooling medium into the respective cooling channel 24 and at least one cooling medium outlet 30 for allowing the cooling medium to exit from the respective cooling channel 24 (see Fig. 2 ).
  • the cooling medium inlets 28 and one of the cooling medium outlets 30 are depicted in Fig. 2 .
  • the cooling medium inlets 28 and the cooling medium outlets 30 may be arranged in a side wall 34 of the transformer and/or the winding 10, as shown in Fig. 2 .
  • the cooling channels 24 may be at least partially embedded within the electrically insulating material 22.
  • the cooling channels 24 may be embedded between an inner layer 40 and an outer layer 42 of the electrically insulating material 22.
  • the outer layer 42 may be arranged radially outside of the inner layer 40.
  • the cooling medium inlets 28 and/or the cooling medium outlets 30 may be arranged such that the cooling medium can enter the respective cooling channel 24 via the cooling medium inlets 28 and/or can exit the respective cooling channel 24 via the cooling medium outlets 30 substantially radially with respect to a circumference of the winding 10 and/or substantially perpendicularly to the longitudinal axis LA of the winding 10 and/or the transformer and/or the core and/or substantially perpendicularly to a winding axis WA of one or more of the winding portions 16, when the winding 10 is operatively installed in the transformer.
  • the cooling medium may enter into and exit from the respective cooling channel 24 at other (non-radial) angles.
  • At least some of the cooling channels 24, preferably all of the cooling channels 24, may extend about at least 50%, preferably at least 60%, more preferably at least 70%, more preferably at least 80%, more preferably at least 90%, of a circumference of the core of the transformer, when the winding 10 is arranged around the core.
  • At least some of the cooling channels 24, e.g., the first cooling channel 24A and the second cooling channel 24B, preferably each of the plurality of cooling channels 24, may be part of and/or are connected to an open cooling circuit.
  • the cooling medium inlet(s) 28 and the cooling medium outlet(s) 30 of at least one of the cooling channels 24 may be positioned such that a plane, which extends substantially perpendicularly to a longitudinal axis of the winding 10 and/or the transformer and/or the core and/or substantially perpendicularly to a winding axis WA of one or more of the winding portions 16, when the winding 10 is operatively installed in the transformer, extends through the cooling medium inlet 28 and the cooling medium outlet 30 of the respective cooling channels 24.
  • the plane may extend through a center of the cooling medium inlet 28 and a center of the cooling medium outlet 30.
  • the plane may extend through the entire respective cooling channel 24, e.g., the entire first cooling channel 24A or the entire second cooling channel 24B.
  • the cooling medium inlets 28 and/or the cooling medium outlets 30 may be arranged in a section 50 of the side wall 34 of the transformer and/or a side wall 34 of the winding 10 which is substantially flat.
  • at least some of the cooling medium inlets 28 and/or the cooling medium outlets 30, preferably all of the cooling medium inlets 28 and/or the cooling medium outlets 30, are arranged in a dome structure 52 of the side wall 34 of the winding 10 and/or the transformer.
  • the winding 10 may include at least one flow generating device 60.
  • the flow generating device 60 may be configured to be powered, preferably electrically, to generate a forced convection flow of the cooling medium through the cooling channels 24.
  • the flow generating device 60 may be arranged upstream from the cooling medium inlets 28 to blow the cooling medium, e.g., air, into the cooling medium inlets 28, as shown in Figs. 3 and 4 .
  • the winding 10 may include at least one flow generating device, e.g., the flow generating device 60 mentioned above or a further flow generating device, which is configured and arranged to suck the cooling medium, e.g., air, out of the cooling medium outlets 30.
  • the flow generating device may be arranged downstream from the cooling medium outlets 30.
  • the flow of cooling medium may be caused by natural convection only.
  • the winding 10 may include at least one cooling medium supply device 64 configured to supply and distribute the cooling medium to each of the cooling medium inlets 28, as shown in Figs. 3 and 4 .
  • the winding 10 may include at least one cooling medium outlet device 66 configured to collect and guide the cooling medium from each of the cooling medium outlets 30.
  • the cooling medium outlet device 66 has been omitted from Fig. 4 .
  • the cooling medium supply device 64 may include a cooling medium supply device inlet 68, preferably a single cooling medium supply device inlet 68, which is fluidically connected or fluidically connectable to each cooling medium inlet 28.
  • the cooling medium outlet device 66 may include a cooling medium outlet device outlet 69, preferably a single cooling medium outlet device outlet 69, which is fluidically connected or fluidically connectable to each cooling medium outlet 30.
  • the cooling channels 24 may have any cross-sectional shape, e.g., round, oval, rectangular, polygonal, etc.
  • the cooling channel 24 shown in Fig. 5A is rectangular.
  • at least some of the cooling channels 24 may include one or more partitioning elements 72, e.g., one or more walls and/or one or more fins, configured to segment or divide a cross-sectional area of the respective cooling channel(s) 24 into two or more sub-areas or partitions 76, preferably three or more sub-areas or partitions.
  • Fig. 6 shows, in a schematic top view, a transformer 80 according to an embodiment of the present disclosure.
  • the transformer 80 may include at least one core 82 and at least one winding 10 according to any of the embodiments described herein, e.g., the winding 10 of Figs. 1 to 4 .
  • the winding 10 may at least partially surround the core 82.

Landscapes

  • Engineering & Computer Science (AREA)
  • Power Engineering (AREA)
  • Manufacturing & Machinery (AREA)
  • Coils Of Transformers For General Uses (AREA)

Abstract

The present invention relates to winding (10) of a dry-type transformer (80) configured to be arranged to surround a core (82) of the transformer (80). The winding (10) includes a first winding portion (16A), a second winding portion (16B), and at least one third winding portion (16C) which each include an electrically conductive material. The winding includes a first gap (20A) which is arranged between the first winding portion (16A) and the second winding portion (16B) and which is filled with electrically insulating material (22), at least a second gap (20B) which is arranged between the second winding portion (16B) and the third winding portion (16C) and which is filled with electrically insulating material (22), and a plurality of cooling channels (24) configured to guide a cooling medium therethrough to transfer heat from the transformer (80) to the cooling medium. The plurality of cooling channels (24) include a first cooling channel (24A) arranged within the first gap (20A) and a second cooling channel (24B) arranged within the second gap (20B). The first cooling channel (24A) and the second cooling channel (24B) each include a medium inlet (28) for introducing the cooling medium into the respective cooling channel (24) and a cooling medium outlet (30) for allowing the cooling medium to exit from the respective cooling channel (24). The cooling medium inlets (28) and the cooling medium outlets (30) are arranged in a side wall (34) of the transformer (80) and/or a side wall (34) of the winding (10).
The present invention further relates to a transformer (80), a method of manufacturing a winding (10) of a transformer (80), and a method of operating a transformer (80).

Description

  • Transformers are widely used to convert electricity from a first voltage level to a second voltage level, the second voltage level being either higher or lower than the first voltage level.
  • The transformer may comprise one or more windings, e.g., one or more primary windings and one or more secondary windings. One or more of the windings may be connected in series or in parallel.
  • Transformers generate heat during operation, in particular due to a power loss dissipated by the transformer in the form of heat. For instance, such a power loss of the transformer comprises core losses and winding or coil losses.
  • Thus, the core and the windings of the transformer generate heat within the transformer, which should be transferred away from the transformer to achieve a better performance, a longer lifetime of the transformer, and lower operational costs of the transformer.
  • It is known to immerse the windings and/or the core in a liquid, particularly an oil, to insulate, and optionally cool, the transformer. Transformers having such a configuration are often referred to as liquid or oil filled transformers.
  • As an alternative, besides immersing the windings and/or the core in a liquid, it is also known to use a gas, such as air, to flow through at least a portion of the transformer, e.g., throughout one or more cooling channels, in order to transfer heat away from the transformer.
  • However, deficiencies remain with respect to the cooling means provided in transformers known from the prior art.
  • For instance, a pressure drop of the flow of cooling medium, i.e., in particular a cooling gas, through the respective cooling channel is relatively large in at least some of the prior art transformers. This may reduce the velocity of the flow of cooling medium and/or may require a larger pressure at an entrance of the cooling channel to achieve the desired and/or target velocity or mass flow of cooling medium, e.g., by using a larger blower and/or by providing more power to the respective blower.
  • Furthermore, the respective cooling channels of at least some of the prior art transformers are arranged and/or positioned and/or orientated in the transformer and/or winding in a manner which is disadvantageous and/or which may negatively affect the transformer, in particular one or more functions and/or the operation of the transformer.
  • In addition, a position and/or an orientation of the respective cooling channel in the transformer and/or winding of at least some of the prior art transformers may be disadvantageous to a cooling system of the respective transformer which includes the cooling channels, in particular the construction and/or the arrangement of one or more further components of the cooling system, of the respective transformer. For instance, an arrangement of one or more further components of the cooling system may negatively affect the one or more functions and/or the operation of the transformer.
  • Moreover, the cooling systems of at least some of the prior art transformers result in a relatively high degree of non-uniformity of cooling in the transformer and/or the winding of the transformer, and thus a relatively uneven heat distribution in the transformer and/or the winding of the transformer. This may result in a relatively high degree of tension and/or damage in the transformer, in particular the winding of the transformer.
  • The prior art has not, or at least not sufficiently, addressed one or more of the disadvantages mentioned above. Therefore, there is a need to improve the cooling of transformers, e.g., in order to improve the performance and/or the lifetime of the transformer and/or to reduce its operational costs.
  • Hence, it is an object of the present invention to provide an improved means of cooling a transformer, in particular by improving one or more of the above-mentioned disadvantages.
  • This object is achieved by a winding of a transformer defined by the features of claim 1. Variations and further developments are defined by the features of the dependent claims.
  • The winding may be a winding of a dry-type transformer. The winding may be configured to be arranged to at least partially surround at least one core of the transformer.
  • The winding may include a plurality of winding portions which each include an electrically conductive material. In particular, the winding may include a first winding portion which includes an electrically conductive material. The winding may include a second winding portion which includes an electrically conductive material. The winding may include at least one third winding portion which includes an electrically conductive material. Optionally, the winding may include one or more further winding portions.
  • The winding may include a plurality of gaps defined at least partially between adjacent winding portions of the plurality of winding portions, in particular between winding portions which are adjacent to each in a direction along a longitudinal axis of the transformer and/or a longitudinal axis of the core and/or a winding axis of one of more of the winding portions. In particular, the winding may include a first gap which may be arranged at least partially between two adjacent winding portions, e.g., between the first winding portion and the second winding portion. The first gap may be at least partially filled with electrically insulating material. The winding may include at least a second gap which is arranged at least partially between two adjacent winding portions, e.g., between the second winding portion and the third winding portion, which may be at least partially filled with electrically insulating material, preferably the same electrically insulating material arranged in the first gap, preferably in all of the gaps.
  • The winding may include a plurality of cooling channels (which may also be referred to as "cooling ducts") configured to guide at least one cooling medium therethrough to transfer heat from the transformer to the cooling medium. The plurality of cooling channels may include a first cooling channel arranged within the first gap and at least a second cooling channel arranged within the second gap. The first cooling channel and/or the second cooling channel may be arranged completely or partially within the respective gap. The respective cooling channel may extend into and/or out of the respective gap.
  • The first cooling channel and the second cooling channel may each include at least one cooling medium inlet for introducing the cooling medium into the respective cooling channel and at least one cooling medium outlet for allowing the cooling medium to exit from the respective cooling channel.
  • The cooling medium inlets and the cooling medium outlets may be arranged in a side wall of the transformer and/or a side wall of the winding. In other words, the cooling medium may be guided into the respective cooling channel through the side wall of the winding, preferably a side wall of the electrically insulating material, and/or the side wall of the transformer.
  • Providing a plurality of cooling channels in a transformer is generally known from the prior art. However, in the respective prior art, the cooling channels are configured as vertical cooling channels which extend from a top of the transformer or winding towards a bottom of the transformer or winding, in particular along a longitudinal axis of the transformer. In other words, the plurality of cooling channels in the concerned prior art result in openings or holes, i.e., the respective cooling channel inlets and/or cooling channel outlets of the respective cooling channels, which are defined in a top side and/or a bottom side of the transformer or winding, in particular in a top side and/or bottom side of an electrically insulating material, e.g., an epoxy resin, of the winding. This may have several disadvantages. For instance, this may result in a weaker electrical insultation of the transformer and/or an electrical insultation which may be more vulnerable to failure, which may be particularly critical for higher voltages, in particular for 36 kV or higher, and/or which may require one or more corresponding countermeasures. This may be particularly disadvantageous at the top side of the winding, since a reliable and robust electrical insulation is generally particularly vital at the top side of the winding.
  • In this regard, providing the cooling medium inlets and the cooling medium outlets in a side wall of the transformer and/or a side wall of the winding, per the winding of the present disclosure, improves the disadvantages mentioned above, by arranging the cooling medium inlets and the cooling medium outlets at positions which are away from or outside of a top side of the winding and/or the transformer, i.e., away from a location on the winding and/or transformer which is relatively critical and/or more critical than the sides (i.e., side wall(s)) of the winding and/or transformer with respect to electrical insulation purposes.
  • Moreover, providing the cooling medium inlets and the cooling medium outlets in a side wall of the transformer and/or a side wall of the winding may facilitate a fluidical connection of the cooling medium inlets and the cooling medium outlets, e.g., to a cooling circuit, e.g., to one or more (further) components of the cooling circuit, e.g., a cooling medium supply and/or a cooling medium distribution device, since it generally may be more convenient to attach and/or arrange said one or more (further) components of the cooling circuit at the side wall(s) of the transformer and/or a side wall of the winding.
  • Furthermore, providing a plurality of cooling channels, as described above, with at least some of the plurality of cooling channels, i.e., at least two of the plurality of cooling channels, i.e., at least the first cooling channel and the second cooling channel, each having at least one cooling medium inlet for introducing the cooling medium into the respective cooling channel and at least one cooling medium outlet for allowing the cooling medium to exit from the respective cooling channel, may allow the respective cooling channels to be individually supplied with the cooling medium, e.g., from a common source of the cooling medium, e.g., via at least one cooling medium supply device, and individually collecting the cooling from the cooling channels. This may reduce a pressure drop in the cooling channels, in particular compared with a single, and thus generally longer, cooling channel. This may allow higher flow velocities and/or higher mass flows of the cooling medium to be achieved in the cooling channels which may increase the heat transfer from the transformer to the cooling medium and/or may allow a power of a flow generating device, e.g., a blower, to be reduced.
  • In addition, providing a plurality of cooling channels, compared with a single (and thus generally longer) cooling channel, may increase a mean temperature difference between the temperature of the transformer, e.g., the electrically insulating material, and the cooling medium which may allow more heat overall to be transferred to the cooling medium. Moreover, this may allow a larger flow of the cooling medium to be guided through the transformer, more particularly the winding. Moreover, this may also provide a more even cooling of the transformer, compared with a single (and thus generally longer) cooling channel, in particular in which a heat transfer may be reduced towards a downstream end of the cooling channel.
  • The winding may include any number of winding portions. For instance, the winding may include at least two winding portions, at least three winding portions, etc. The winding may include more than three winding portions. A gap may be arranged between two sequential and/or adjacent winding portions. At least one of the cooling channels may be arranged at least partially in each of the gaps.
  • The winding may be configured as disc-type winding. In other words, the winding portions, e.g., the first winding portion, the second winding portion, and the third winding portion, may each be configured as a winding disc, preferably a foil disc. The winding may be configured as a Continuously Transposed Cable (CTC) winding.
  • Alternatively, or additionally, the winding portions, e.g., the first winding portion, the second winding portion, and the third winding portion, may be winding layers and/or winding blocks. Alternatively, or additionally, each winding portion, e.g., the first winding portion, the second winding portion, and the third winding portion, may include one or more winding layers, e.g., one or more winding sublayers. The winding layers or winding sublayers may be arranged along, e.g., spaced apart from each other and/or distributed, in a radial direction and/or substantially perpendicularly to the longitudinal axis of the transformer and/or the winding and/or a winding axis of the winding portions. The gaps, e.g., the first gap and/or the second gap, may be arranged between adjacent winding layers or adjacent winding sublayers.
  • The electrically conductive material may have any cross-sectional shape, e.g., round, oval, rectangular, etc.
  • The winding is preferably configured as a vacuum cast coil (VCC).
  • The electrically insulating material may be an epoxy resin. However, alternative electrically insulating materials are also feasible.
  • The winding portions, i.e., the first winding portion, second winding portion, the third winding portion, and optionally one or more further winding portions, are preferably arranged in a stacked manner, in particular along a longitudinal axis of the transformer and/or a longitudinal axis of the core and/or along a winding axis of one or more of the winding portions.
  • The first gap may separate the first winding portion from the second winding portion along at least a section of the first winding portion and the second winding portion. The second gap may separate the second winding portion from the third winding portion along at least a section of the second winding portion and the third winding portion.
  • The first gap and the second gap are preferably spaced apart from each other along a longitudinal axis of the transformer and/or a longitudinal axis of the core and/or along a winding axis of one or more of the winding portions.
  • The winding portions may be connected, in particular electrically connected, in particular by means of at least one interconnecting element, e.g., at least one bar, at least one wire, etc. The interconnecting element may not be wound, e.g., about a winding axis of one or more of the winding portions. Although the interconnecting element may also include an electrically conductive material, the interconnecting element may be distinguished from the winding portions by one or more features. In particular, the interconnecting element may interrupt and/or alter a winding pattern and/or a winding shape of the respective winding portion. For instance, the interconnecting element may extend in an axial direction along a longitudinal axis of the transformer and/or a longitudinal axis of the core and/or along a winding axis of the first winding portion, the second winding portion, and/or the third winding portion at a different angle than the winding portions. Moreover, the interconnecting element may have a different shape, e.g., a different cross-sectional shape, and/or one or more different dimensions, e.g., one of more different dimensions in a cross-section of the interconnecting element, than the winding portions.
  • The side wall of the winding and/or the transformer, in which the cooling medium inlets and the cooling medium outlets are defined within the meaning of the present disclosure, may be a side wall which extends substantially along a longitudinal axis of the transformer and/or a longitudinal axis of the core and/or along a winding axis of one or more of the winding portions. A top side and/or a bottom side, e.g., of the winding, may be connected to the side wall. The side wall may be a side wall defined by the electrically insulating material. In other words, the cooling medium inlets may be inlets into the electrically insulating material and the cooling medium outlets may be outlets which exit the electrically insulating material. In other words, the cooling medium inlets may be arranged and/or defined by the side wall of the electrically insulating material, e.g., the epoxy resin.
  • The winding portions, i.e., the first winding portion, second winding portion, the third winding portion, and optionally one or more further winding portions, may be integrally and/or monolithically connected by the electrically insulating material and/or may be at least partially, preferably completely, embedded or encapsulated in the electrically insulating material, e.g., by a casting process. The electrically insulating material arranged in each gap may be an integrally or monolithically connected mass of electrically insulating material. The electrically insulating material may at least partially, preferably completely, encase or cover the electrically conductive material of each of the winding portions.
  • The cooling channels may be at least partially, preferably completely, embedded or encapsulated in the electrically insulating material, e.g., by a casting process.
  • At least some of the cooling channels may be fluidically interconnected, in particular at one or more sections downstream of the respective cooling medium inlet. At least some of the cooling channels may share at least one cooling medium inlet and/or at least one cooling medium outlet, as described further below in more detail.
  • Preferably, the cooling medium inlets and/or the cooling medium outlets are arranged such that the cooling medium can enter the cooling channel via the cooling medium inlets and/or can exit the cooling channel via the cooling medium outlets substantially radially with respect to a circumference of the winding and/or substantially perpendicularly to a longitudinal axis of the winding and/or the transformer and/or the core and/or substantially perpendicularly to a winding axis of the first winding portion and the second winding portion, when the winding is operatively installed in the transformer. This may facilitate a connection to the cooling medium inlets and/or the cooling medium outlets, e.g., a connection of one or more conduits and/or one or more further components of a cooling system, e.g., a cooling medium supply device, to the cooling medium inlets and/or the cooling medium outlets.
  • Preferably, the cooling medium inlets and the cooling medium outlets are arranged in a section of the side wall of the transformer and/or a side wall of the winding which is substantially flat. This may facilitate connecting a cooling system and/or a cooling circuit and/or a conduit to the cooling medium inlets and the cooling medium outlets and/or may reduce a risk of leakage at the cooling medium inlets and/or the cooling medium outlets, i.e., at the above-mentioned connection(s). Preferably, the cooling medium inlets and the cooling medium outlets are arranged in a dome structure of the side wall of the winding. The dome structure may extend from a body of the winding, in particular in a protrusion-like manner. Most cast-type windings, in particular windings which are cast using epoxy resin as an electrically insulating material, are filled with epoxy in a horizontal orientation which creates a substantially flat surface, often referred to as a "dome" or "dome structure". The "dome" or "dome structure" provides a region for the customer to makes connections to the transformer and therefore often houses one or more taps, e.g., start taps, finish taps, as well as voltage adjustment taps. Thus, this "dome" or "dome structure", which is often already present on respective windings or is innately created during the manufacturing process of the winding, in particular during a casting process, may be utilized for positioning the cooling medium inlets and the cooling medium outlets which may provide one or more benefits, as discussed above.
  • Preferably, the cooling medium is a gas, preferably air, preferably ambient air.
  • Preferably, the first cooling channel and the second cooling channel, preferably each of the plurality of cooling channels, are part of and/or are connected to an open cooling circuit. An "open cooling circuit", within the meaning of the present disclosure, means a non-circulating circuit, i.e., the cooling medium is not refed from the cooling medium outlet to the cooling medium inlet. Preferably, the winding is configured to introduce ambient air (as the "cooling medium") into the cooling channels via the cooling medium inlets and discharge the ambient air, which has absorbed heat from the transformer, to the ambient via the cooling medium outlets. This may simplify the construction of the winding and/or the transformer, e.g., by being able to omit an external heat exchanger.
  • Preferably, a plane, which extends substantially perpendicularly to a longitudinal axis of the winding and/or the transformer and/or the core and/or substantially perpendicularly to a winding axis of the first winding portion and the second winding portion, when the winding is operatively installed in the transformer, extends through the cooling medium inlet and the cooling medium outlet of the first cooling channel or the cooling medium inlet and the cooling medium outlet of the second cooling channel. The plane may be referred to as a horizontal plane. This may facilitate connecting a cooling system and/or a cooling circuit and/or a conduit to the cooling medium inlets and the cooling medium outlets and/or may reduce a risk of leakage at the cooling medium inlets and/or the cooling medium outlets, i.e., at the above-mentioned connection(s). Preferably, the plane extends through a center of the cooling medium inlet and a center of the cooling medium outlet. Preferably, the plane extends through the entire first cooling channel or the entire second cooling channel.
  • Preferably, at least one gap is arranged at least partially between each pair of adjacent winding portions of the winding and at least one of the plurality of cooling channels is arranged at least partially within each gap and the respective cooling medium inlet and cooling medium outlet of the respective cooling channel are arranged in a side wall of the transformer and/or a side wall of the winding.
  • Preferably, the cooling medium inlets and the cooling medium outlets are arranged such that the cooling medium can enter the respective cooling channel via the cooling medium inlets and the cooling mediums can exit the respective cooling channel via the cooling medium outlets in substantially opposite directions. This may allow the respective cooling medium inlet(s) and the cooling medium outlet(s) of the respective cooling channel to be arranged relatively close to each other, e.g., on the same side and/or the same region of the transformer and/or the winding.
  • Preferably, the cooling channels are spaced apart from each other along a longitudinal axis of the winding and/or the transformer and/or the core, when the winding is operatively installed in the transformer. In particular, at least some of the electrically insulating material may be arranged between the cooling channels, in particular between adjacent cooling channels. At least some of the cooling channels, preferably all of the cooling channels, may extend substantially parallel to each other. Alternatively, or additionally, a first plane which extends through one cooling channel, e.g., the first cooling channel, of the cooling channels may be parallel to a second plane which extends through another cooling channel, e.g., the second cooling channel, of the cooling channels, preferably an adjacent cooling channel.
  • Preferably, the winding further includes at least one cooling medium supply device configured to supply and distribute the cooling medium to each of the cooling medium inlets. This may allow the cooling medium to be supplied to the cooling channels via a common device, i.e., the cooling medium supply device. Preferably, the cooling medium supply device includes a cooling medium supply device inlet, preferably a single cooling medium supply device inlet, which is fluidically connected or fluidically connectable to each cooling medium inlet. Providing the above-described cooling medium supply device may facilitate operation of the cooling of the transformer and/or assembly and/or disassembly of the transformer. In addition, this may provide a more compact and reliable construction, e.g., compared with supplying each cooling medium inlet individually, e.g., via cooling medium hoses, with the cooling medium. Moreover, this may also facilitate providing a sufficient fluidical sealing of the cooling channels, in particular at the cooling medium inlets, and/or may improve the fluidical sealing. Alternatively, or additionally, the winding may further include at least one cooling medium outlet device configured to collect and guide the cooling medium from each of the cooling medium outlets. The cooling medium outlet device may include a cooling medium outlet device exit, preferably a single cooling medium outlet device exit, which is fluidically connected or fluidically connectable to each cooling medium outlet. The advantages, as discussed above with respect to the cooling medium supply device, apply to the cooling medium outlet device accordingly.
  • The cooling medium supply device and/or the cooling medium outlet device may each be configured as an air box or a manifold.
  • Preferably, each of the plurality of cooling channels includes a cooling medium inlet for introducing a cooling medium into the cooling channel and/or a cooling medium outlet for allowing the cooling medium to exit from the cooling channel. In other words, each cooling channel may have its own cooling medium inlet and/or cooling medium outlet. This may allow a greater mass flow of the cooling medium to be achieved and/or may reduce a pressure loss of the cooling medium at the cooling medium inlets and/or the cooling medium outlets.
  • Alternatively, at least two of the plurality of cooling channels may include a common cooling medium inlet for introducing a cooling medium into the at least two of the plurality of cooling channels and/or a common cooling medium outlet for allowing the cooling medium to exit from the at least two of the plurality of cooling channels. This may reduce a number of fluidical connections to the cooling channels and/or may reduce a risk of leakage at the cooling medium inlets and/or the cooling medium outlets.
  • Preferably, at least some of the cooling channels include one or more partitioning elements configured to segment a cross-sectional area of the respective cooling channel(s) into two or more partitions, preferably three or more partitions. The one or more partitioning elements may allow the flow of cooling medium to be manipulated and/or enhanced, e.g., by altering a shape and/or one or more dimensions of the respective cooling channel(s). In addition, this may allow the flow of cooling medium to be guided more precisely. Moreover, this may allow turbulence in the flow of the cooling medium to be reduced and/or increased, e.g., to reduce flow separation and/or improve the properties of a boundary layer of the cooling medium in the respective cooling channel(s). This may improve the cooling efficiency and/or effectiveness. Furthermore, the one or more partitioning elements may provide a mechanical reinforcement to the respective cooling channel(s), e.g., to increase the stability of the respective cooling channel(s). Preferably, the partitions extend substantially parallel to each other and/or coaxially and/or are arranged side-by-side. Alternatively, the partitions may extend at different angles to each other.
  • Preferably, at least a first partition of the partitions is arranged adjacent to a further partition of the partitions in a direction which extends substantially radially, in particular with respect to a longitudinal axis of the transformer and/or the core and/or a winding axis of one or more of the winding portions. In other words, at least two partitions, i.e., the first partition and the further partition, may be arranged side-by-side in a radial direction. This may allow multiple compartments to be provided radially in the cooling channel(s). In other words, the cooling channel(s) may be divided into multiple compartments radially. For instance, this may allow to improve the properties of a boundary layer of the flow of cooling medium on a radially inner side of the cooling channel(s), in particular by forcing more of the cooling medium to flow closer to the radially inner side of the cooling channel(s). This may increase the cooling effect and/or the cooling efficiency. Alternatively, or additionally, at least a first partition of the partitions is arranged adjacent to a further partition of the partitions in a direction which extends substantially perpendicularly to a longitudinal axis of the transformer and/or the core and/or a winding axis of one or more of the winding portions. This may provide a greater distribution of the cooling medium in the cooling channel(s) and/or may allow a distribution of cooling medium in the cooling channel(s) to be adjusted.
  • Preferably, at least a first partition of the partitions is arranged adjacent to a further partition of the partitions along a longitudinal axis of the transformer and/or the core and/or along a winding axis of the first winding portion and second winding portion. This may allow multiple compartments to be provided axially in the cooling channel(s). In other words, the cooling channel(s) may be divided into multiple compartments axially. This may provide a greater axial distribution of the cooling medium in the cooling channel(s) and/or may allow an axial distribution of cooling medium in the cooling channel(s) to be adjusted.
  • Preferably, at least a section of the cooling channels extends annularly or semi-annularly along at least a section of the winding. In other words, the cooling channels may be curved in at least a section thereof. This may allow the cooling channels to cover a relatively large portion of the winding to absorb heat from a relatively large portion of the winding. The cooling channels, of which at least a section extends annularly or semi-annularly along at least a section of the winding, may extend in any shape, e.g., in a circular shape, an oval shape, or a rectangular shape. In other words, the term "annularly" or "semi-annularly" does not limit the shape of the cooling channel to a circular shape.
  • Preferably, the winding is configured to achieve a velocity of the cooling medium through the cooling channels of at least 10 m/s, preferably at least 12.5 m/s, more preferably at least 15 m/s, more preferably at least 17.5 m/s, more preferably at least 20 m/s. Such relatively high velocities may increase a mass flow of the cooling medium through the cooling channels and/or may increase a heat transfer coefficient of a heat transfer from the transformer, in particular the winding, to the cooling medium. This may increase the heat transfer from the transformer, in particular the winding, to the cooling medium.
  • Preferably, the winding is configured to achieve a heat transfer coefficient between a wall of the cooling channels and the cooling medium of at least 20 w/(m2*K), preferably at least 25 w/(m2*K), more preferably at least 30 w/(m2*K), more preferably at least 35 w/(m2*K), more preferably at least 40 w/(m2*K), more preferably at least 45 w/(m2*K), more preferably at least 50 w/(m2*K).
  • Preferably, the winding is a high-voltage, HV, winding or a low-voltage, LV, winding.
  • Preferably, the winding includes at least one pipe having a lumen which defines and/or is the respective cooling channel. Preferably, the pipe is at least partially embedded in the electrically insulating material. The pipe may be made of plastic. Alternatively, or additionally, the pipe may be made a 3D printed component. Preferably, the pipe is made of an electrically insulating material, e.g., epoxy resin.
  • Preferably, the pipe is flexible and/or bendable, in a state of the pipe before assembly of the winding. This may facilitate a process of manufacturing the winding and/or the transformer, in particular of providing or integrating the cooling channels in the winding, more specifically in the electrically insulating material.
  • Preferably, at least some of the cooling channels are configured to redirect the cooling medium by at least 90°, preferably at least 120°, more preferably at least 150°, more preferably at least 180°, more preferably at least 210°, more preferably at least 240°, more preferably at least 270°, more preferably at least 300°, more preferably at least 330°, more preferably by 360°. The angle(s) mentioned above may be understood as an angle between a direction in which the cooling medium inlet of the respective cooling channel faces and/or is directed and a direction in which the cooling medium outlet of the respective cooling channel faces and/or is directed, i.e., such that an angle of 360° may mean that the cooling medium inlet and the cooling medium outlet of the respective cooling channel are directed and/or face in substantially the same direction. This may allow the cooling channels to cover a relatively large portion of the winding to absorb heat from a relatively large portion of the winding.
  • Preferably, at least some of the cooling channels are configured to guide the cooling medium about at least 50%, preferably at least 60%, more preferably at least 70%, more preferably at least 80%, more preferably at least 90%, of a circumference of the core of the transformer, when the winding is operatively installed in the transformer.
  • Preferably, the winding further includes at least one flow generating device which can be powered, preferably electrically, to generate a forced convection flow of the cooling medium through the cooling channels.
  • Preferably, the first winding portion, the second winding portion, and the third winding portion are stacked along a longitudinal axis of the transformer and/or a longitudinal axis of the core and/or along a winding axis of the first winding portion, the second winding portion, and/or the third winding portion.
  • The present disclosure also relates to a transformer which may include at least one core and at least one winding, preferably at least one winding according to any of the embodiments described herein, which at least partially surrounds the core.
  • Preferably, the transformer further includes at least one flow generating device, preferably at least one flow generating device which can be powered, preferably electrically, to generate a forced convection flow of the cooling medium through the cooling channels. This may increase a mass flow of the cooling medium through the cooling channels, compared with a natural convection flow. The flow generating device may be configured and arranged to force, i.e., blow or push, the cooling medium, e.g., air, into the cooling medium inlets. In other words, the flow generating device may be arranged upstream from the cooling medium inlets. Alternatively, or additionally, the transformer may include at least one flow generating device, e.g., the flow generating device mentioned above or a further flow generating device, which is configured and arranged to suck the cooling medium, e.g., air, out of the cooling medium outlets. In other words, the flow generating device may be arranged downstream from the cooling medium outlets. Alternatively, the flow of cooling medium may be caused by natural convection only.
  • Preferably, the transformer is free of a radiator. A "radiator", within the context of the present disclosure, means a heat exchanging device in addition to the cooling channels provided in the winding and in a narrower sense, i.e., a heat exchanging device whose only or at least primary function is to exchange heat, e.g., a shell and tube heat exchanger, etc. In other words, the transformer may be free of a radiator which is arranged externally of the winding. In other words, the cooling channels may not be connected to a radiator. Instead, for instance, the cooling channels may be part of an opening cooling circuit (as mentioned above). In particular, the cooling medium may be drawn into the cooling medium inlets from the ambient and/or environment and/or at ambient conditions, i.e., the cooling medium may be drawn from the ambient and/or environment without prior conditioning, in particular cooling, and the cooling medium may be discharged into the ambient and/or environment.
  • The object mentioned at the beginning is also achieved by a method of manufacturing a winding of a transformer, preferably a winding according to any of the embodiments described herein. The features, embodiments, and advantages, as detailed herein with respect to the winding, apply to the method accordingly.
  • The steps of the method described herein are not limited to a particular sequence and may be performed in any technically feasible sequence.
  • The winding may be configured to be arranged to at least partially surround a core of the transformer.
  • The method may include:
    arranging a first winding portion which includes an electrically conductive material.
  • The method may include:
    arranging a second winding portion which includes an electrically conductive material such that a first gap is arranged at last partially between the first winding portion and the second winding portion.
  • The method may include:
    • arranging at least one third winding portion which includes an electrically conductive material such that a second gap is arranged at last partially between the second winding portion and
    • the third winding portion.
  • The method may include:
    providing a plurality of cooling channels configured to guide at least one cooling medium therethrough to transfer heat from the transformer to the cooling medium.
  • The plurality of cooling channels may include a first cooling channel arranged within the first gap and at least a second cooling channel arranged within the second gap.
  • The first cooling channel and the second cooling channel may each include at least one cooling medium inlet for introducing the cooling medium into the respective cooling channel and at least one cooling medium outlet for allowing the cooling medium to exit from the respective cooling channel. The cooling medium inlets and the cooling medium outlets may be arranged in a side wall of the transformer.
  • The method may include:
    filling the first gap and the second gap at least partially with an electrically insulating material.
  • Preferably, the cooling channels are provided by arranging at least one pipe, preferably a plurality of pipes, at least partially in the respective gap and embedding the pipe(s) least partially in the electrically insulating material. The pipe(s) preferably has/have a lumen which defines and/or is the respective cooling channel.
  • The object mentioned at the beginning is also achieved by a method of operating a transformer, preferably a dry-type transformer, preferably the transformer according to any of the embodiments described herein. The features, embodiments, and advantages, as detailed herein with respect to the winding, apply to the method accordingly.
  • The steps of the method described herein are not limited to a particular sequence and may be performed in any technically feasible sequence.
  • The transformer may include at least one core and at least one winding at least partially surrounding the core. The winding may include a plurality of winding portions. The winding portions may include a first winding portion which includes an electrically conductive material, a second winding portion which includes an electrically conductive material, and at least one third winding portion which includes an electrically conductive material. The winding may include a first gap which is arranged at least partially between the first winding portion and the second winding portion and which is at least partially filled with electrically insulating material and at least a second gap which is arranged at least partially between the second winding portion and the third winding portion and which is at least partially filled with electrically insulating material. The winding may include and a plurality of cooling channels configured to guide at least one cooling medium therethrough to transfer heat from the transformer to the cooling medium. The plurality of cooling channels may include a first cooling channel arranged within the first gap and at least a second cooling channel arranged within the second gap.
  • The method may include:
    introducing the cooling medium into the first cooling channel through at least one cooling medium inlet of the first cooling channel and into the second cooling channel through at least one cooling medium inlet of the second cooling channel.
  • The cooling medium inlets may be arranged in a side wall of the transformer and/or a side wall of the winding.
  • The method may include:
    discharging the cooling medium from the first cooling channel through at least one cooling medium outlet of the first cooling channel and from the second cooling channel through at least one cooling medium outlet of the second cooling channel.
  • The cooling medium outlets may be arranged in a side wall of the transformer and/or a side wall of the winding.
  • The following list of aspects provides preferred embodiments of the present disclosure:
    1. 1. A winding of a transformer, preferably a dry-type transformer, the winding being configured to be arranged to at least partially surround at least one core of the transformer, the winding including:
      • a plurality of winding portions which each include an electrically conductive material;
      • preferably wherein the plurality of winding portions include:
        • a first winding portion which includes an electrically conductive material;
        • a second winding portion which includes an electrically conductive material,
        • at least one third winding portion which includes an electrically conductive material;
      • at least one gap, preferably a first gap, which is arranged at least partially between two of the winding portions, preferably between the first winding portion and the second winding portion, the gap being at least partially filled with electrically insulating material;
      • preferably at least a second gap which is arranged at least partially between two of the winding portions, preferably between the second winding portion and the third winding portion, and which is at least partially filled with electrically insulating material;
      • a plurality of cooling channels configured to guide at least one cooling medium therethrough to transfer heat from the transformer to the cooling medium, preferably wherein the plurality of cooling channels include a first cooling channel arranged within the first gap and at least a second cooling channel arranged within the second gap,
      • preferably wherein one or more of the cooling channels, preferably the first cooling channel and the second cooling channel, each include at least one cooling medium inlet for introducing the cooling medium into the respective cooling channel and at least one cooling medium outlet for allowing the cooling medium to exit from the respective cooling channel,
      • preferably wherein the cooling medium inlet(s) and the cooling medium outlet(s) is/are arranged in a side wall of the transformer and/or a side wall of the winding.
    2. 2. The winding according to aspect 1, wherein the cooling medium inlets and/or the cooling medium outlets are arranged such that the cooling medium can enter the cooling channel via the cooling medium inlets and/or can exit the cooling channel via the cooling medium outlets substantially radially with respect to a circumference of the winding and/or substantially perpendicularly to a longitudinal axis of the winding and/or the transformer and/or the core and/or substantially perpendicularly to a winding axis of the first winding portion and the second winding portion, when the winding is operatively installed in the transformer.
    3. 3. The winding according to aspect 1 or 2, wherein the cooling medium is a gas, preferably air, preferably ambient air.
    4. 4. The winding according to any of aspects 1 to 3, wherein the first cooling channel and the second cooling channel, preferably each of the plurality of cooling channels, are part of and/or are connected to an open cooling circuit.
    5. 5. The winding according to any of aspects 1 to 4, wherein a plane, which extends substantially perpendicularly to a longitudinal axis of the winding and/or the transformer and/or the core and/or substantially perpendicularly to a winding axis of the first winding portion and the second winding portion, when the winding is operatively installed in the transformer, extends through the cooling medium inlet and the cooling medium outlet of the first cooling channel or the cooling medium inlet and the cooling medium outlet of the second cooling channel.
    6. 6. The winding according to aspect 5, wherein the plane extends through a center of the cooling medium inlet and a center of the cooling medium outlet.
    7. 7. The winding according to aspect 5 or 6, wherein the plane extends through the entire first cooling channel or the entire second cooling channel.
    8. 8. The winding according to any of the preceding aspects, wherein at least one gap is arranged at least partially between each pair of adjacent winding portions of the winding and at least one of the plurality of cooling channels is arranged at least partially within each gap and the respective cooing medium inlet and cooling medium outlet of the respective cooling channel are arranged in a side wall of the transformer and/or a side wall of the winding.
    9. 9. The winding according to any of the preceding aspects, wherein the cooling medium inlets and the cooling medium outlets are arranged such that the cooling medium can enter the respective cooling channel via the cooling medium inlets and the cooling mediums can exit the respective cooling channel via the cooling medium outlets in substantially opposite directions.
    10. 10. The winding according to any of the preceding aspects, wherein the cooling channels are spaced apart from each other along a longitudinal axis of the winding and/or the transformer and/or the core, when the winding is operatively installed in the transformer.
    11. 11. The winding according to any of the preceding aspects, further including:
      • at least one cooling medium supply device configured to supply and distribute the cooling medium to each of the cooling medium inlets;
        and/or
      • at least one cooling medium outlet device configured to collect and guide the cooling medium from each of the cooling medium outlets.
    12. 12. The winding according to aspect 11, wherein:
      • the cooling medium supply device includes a cooling medium supply device inlet,
      • preferably a single cooling medium supply device inlet, which is fluidically connected or fluidically connectable to each cooling medium inlet;
        and/or
      • the cooling medium outlet device includes a cooling medium outlet device exit, preferably a single cooling medium outlet device exit, which is fluidically connected or fluidically connectable to each cooling medium outlet.
    13. 13. The winding according to any of the preceding aspects, wherein each of the plurality of cooling channels includes a cooling medium inlet for introducing a cooling medium into the cooling channel and a cooling medium outlet for allowing the cooling medium to exit from the cooling channel.
    14. 14. The winding according to any of aspects 1 to 12, wherein at least two of the plurality of cooling channels include a common cooling medium inlet for introducing a cooling medium into the at least two of the plurality of cooling channels and a common cooling medium outlet for allowing the cooling medium to exit from the at least two of the plurality of cooling channels.
    15. 15. The winding according to any of the preceding aspects, wherein at least some of the cooling channels include one or more partitioning elements configured to segment a cross-sectional area of the respective cooling channel(s) into two or more partitions, preferably three or more partitions.
    16. 16. The winding according to any of the preceding aspects, wherein the partitions extend substantially parallel to each other and/or coaxially and/or are arranged side-by-side.
    17. 17. The winding according to aspect 15 or 16, wherein at least a first partition of the partitions is arranged adjacent to a further partition of the partitions in a direction:
      • which extends substantially radially;
        and/or
      • substantially perpendicularly to a longitudinal axis of the transformer and/or the core and/or a winding axis of the first winding portion and second winding portion.
    18. 18. The winding according to any of aspects 15 to 17, wherein at least a first partition of the partitions is arranged adjacent to a further partition of the partitions along a longitudinal axis of the transformer and/or the core and/or along a winding axis of the first winding portion and second winding portion.
    19. 19. The winding according to any of the preceding aspects, wherein at least a section of the cooling channels extends annularly or semi-annularly along at least a section of the winding.
    20. 20. The winding according to any of the preceding aspects, wherein at least a section of the cooling channels is curved.
    21. 21. The winding according to any of the preceding aspects, wherein the winding is configured as a vacuum cast coil, VCC, winding.
    22. 22. The winding according to any of the preceding aspects, wherein the winding is configured to achieve a velocity of the cooling medium through the cooling channels of at least 10 m/s, preferably at least 12.5 m/s, more preferably at least 15 m/s, more preferably at least 17.5 m/s, more preferably at least 20 m/s.
    23. 23. The winding according to any of the preceding aspects, wherein the winding is configured to achieve a heat transfer coefficient between a wall of the cooling channels and the cooling medium of at least 20 w/(m2*K), preferably at least 25 w/(m2*K), more preferably at least 30 w/(m2*K), more preferably at least 35 w/(m2*K), more preferably at least 40 w/(m2*K), more preferably at least 45 w/(m2*K), more preferably at least 50 w/(m2*K).
    24. 24. The winding according to any of the preceding aspects, wherein the winding is a high-voltage, HV, winding or a low-voltage, LV, winding.
    25. 25. The winding according to any of the preceding aspects, including at least one pipe having a lumen which defines and/or is the respective cooling channel, preferably wherein the pipe is at least partially embedded in the electrically insulating material.
    26. 26. The winding according to aspect 25, wherein the pipe is flexible and/or bendable, in a state of the pipe before assembly of the winding.
    27. 27. The winding according to any of the preceding aspects, wherein at least some of the cooling channels are configured to redirect the cooling medium by at least 90°, preferably at least 120°, more preferably at least 150°, more preferably at least 180°.
    28. 28. The winding according to any of the preceding aspects, wherein at least some of the cooling channels are configured to guide the cooling medium about at least 50%, preferably at least 60%, more preferably at least 70%, more preferably at least 80%, more preferably at least 90%, of a circumference of the core of the transformer, when the winding is operatively installed in the transformer.
    29. 29. The winding according to any of the preceding aspects, further including at least one flow generating device which can be powered, preferably electrically, to generate a forced convection flow of the cooling medium through the cooling channels.
    30. 30. The winding according to any of the preceding aspects, wherein the first winding portion, the second winding portion, and the third winding portion are stacked along a longitudinal axis of the transformer and/or a longitudinal axis of the core and/or along a winding axis of the first winding portion, the second winding portion, and/or the third winding portion.
    31. 31. The winding according to any of the preceding aspects, wherein the cooling medium inlets and the cooling medium outlets are arranged in a section of the side wall of the transformer and/or a side wall of the winding which is substantially flat, preferably wherein the cooling medium inlets and the cooling medium outlets are arranged in a dome structure of the side wall of the winding and/or the transformer.
    32. 32. A transformer which includes at least one core and at least one winding according to any of the preceding aspects which at least partially surrounds the core.
    33. 33. The transformer according to aspect 32, further including at least one flow generating device which can be powered, preferably electrically, to generate a forced convection flow of the cooling medium through the cooling channels.
    34. 34. The transformer according to aspect 32 or 33, wherein the transformer is free of a radiator.
    35. 35. A method of manufacturing a winding of a transformer, preferably the winding of any of aspects 1 to 31, the winding being configured to be arranged to at least partially surround at least one core of the transformer, including:
      • arranging a first winding portion which includes an electrically conductive material;
      • arranging a second winding portion which includes an electrically conductive material such that a gap, preferably a first gap, is arranged at last partially between the first winding portion and the second winding portion;
      • preferably arranging at least one third winding portion which includes an electrically conductive material such that a second gap is arranged at last partially between the second winding portion and the third winding portion;
      • providing a plurality of cooling channels configured to guide at least one cooling medium therethrough to transfer heat from the transformer to the cooling medium, preferably wherein the plurality of cooling channels include a first cooling channel arranged within the first gap and at least a second cooling channel arranged within the second gap, wherein one or more of the cooling channels, preferably the first cooling channel and the second cooling channel, each include at least one cooling medium inlet for introducing the cooling medium into the respective cooling channel and at least one cooling medium outlet for allowing the cooling medium to exit from the respective cooling channel, preferably wherein the cooling medium inlet(s) and the cooling medium outlet(s) is/are arranged in a side wall of the transformer;
      • filling the gap, preferably the first gap and the second gap, at least partially with an electrically insulating material.
    36. 36. The method according to aspect 35, wherein the cooling channels are provided by arranging at least one pipe, preferably a plurality of pipes, at least partially in the respective gap and embedding the pipe(s) least partially in the electrically insulating material, preferably wherein the pipe(s) has/have a lumen which defines and/or is the respective cooling channel.
    37. 37. A method of operating a transformer, preferably a dry-type transformer, preferably the transformer of any of aspects 32 to 34, the transformer including at least one core and at least one winding at least partially surrounding the core, the winding including a plurality of winding portions which each include an electrically conductive material, preferably wherein the plurality of winding portions include a first winding portion which includes an electrically conductive material, a second winding portion which includes an electrically conductive material, and at least one third winding portion which includes an electrically conductive material, the transformer further including at least one gap, preferably a first gap, which is arranged at least partially between two of the winding portions, preferably between the first winding portion and the second winding portion, the gap being at least partially filled with electrically insulating material, preferably at least a second gap which is arranged at least partially between two of the winding portions, preferably between the second winding portion and the third winding portion, and which is at least partially filled with electrically insulating material, and a plurality of cooling channels configured to guide at least one cooling medium therethrough to transfer heat from the transformer to the cooling medium, preferably wherein the plurality of cooling channels include a first cooling channel arranged within the first gap and at least a second cooling channel arranged within the second gap, the method including:
      • introducing the cooling medium through at least one cooling medium inlet of at least one of the cooling channels, preferably the first cooling channel, and preferably through at least one cooling medium inlet of the second cooling channel, the cooling medium inlet(s) preferably being arranged in a side wall of the transformer and/or a side wall of the winding;
      • discharging the cooling medium from the respective cooling channel(s), preferably the first cooling channel, through at least one cooling medium outlet of the respective cooling channel(s), and preferably from the second cooling channel through at least one cooling medium outlet of the second cooling channel, the cooling medium outlet(s) preferably being arranged in a side wall of the transformer and/or a side wall of the winding.
  • Preferred embodiments of the present invention are further elucidated below with reference to the figures. The described embodiments are merely exemplary and do not limit the present invention, as defined by the claims and their respective equivalents.
    • Fig. 1
    shows, in a schematic and cross-sectional view, a winding of a transformer according to an embodiment of the present disclosure;
    Fig. 2
    shows, in a further schematic and cross-sectional view, the winding of Fig. 1;
    Fig. 3
    shows, in a schematic front view, a modification of the winding of Figs. 1 and 2;
    Fig. 4
    shows, in a schematic side view, the winding of Fig. 3;
    Figs. 5A-5C
    show, in schematic and cross-sectional views, embodiments of the cooling channels of the winding of Figs. 1 to 4;
    Fig. 6
    shows, in a schematic top view, a transformer according to an embodiment of the present disclosure.
  • Figs. 1 to 4 schematically show a winding 10 of a transformer, in particular a dry-type transformer. The winding 10 may be configured to be arranged to at least partially surround a core of the transformer.
  • Fig. 1 shows a longitudinal cross-sectional view of the winding 10, i.e., a view of a cut of the winding 10 along a longitudinal axis of the winding 10. Fig. 2 shows a view of a cross-section of the winding 10 which is substantially perpendicular to the longitudinal axis of the winding 10. Fig. 3 shows a front view of the winding 10 and Fig. 4 shows a side view of the winding 10. The longitudinal axis of the winding 10 is shown in Fig. 2 (indicated as "LA"), which extends into and out of the drawing plane based on the illustration in Fig. 2, and in Figs. 3 and 4. The longitudinal axis LA of the winding 10 may coincide with the longitudinal axis of the transformer.
  • The winding 10 may include a plurality of winding portions 16 which each include an electrically conductive material. The plurality of winding portions 16 may include a first winding portion 16A, a second winding portion 16B, and a third winding portion 16C. The number of winding portions 16 is only an example. The winding 10may have less or more winding portions 16 than shown in the Figures.
  • The winding portions 16 may each be wound about a winding axis WA. The winding axis WA may coincide with the longitudinal axis LA of the winding 10 and/or the longitudinal axis of the transformer, as shown in the Figures. Alternatively, the winding axis WA may not coincide with the longitudinal axis LA. Instead, the winding axis WA may extend parallel or at an angle to the longitudinal axis LA.
  • The winding 10 may include one or more gaps 20 which are arranged at least partially between at least two of the winding portions 16. For instance, a first gap 20A may be arranged between the first winding portion 16A and the second winding portion 16B, as shown in Fig. 1. The one or more gaps 20 may include at least a second gap 20B which may be arranged at least partially between at least two of the winding portions 16, e.g., between the second winding portion 16B and the third winding portion 16C. The one or more gaps 20, e.g., the first gap 20A and/or the second gap 20B, may be at least partially filled with electrically insulating material 22.
  • The winding 10 may include a plurality of channels 24, preferably a plurality of cooling channels 24, which may be configured to guide at least one cooling medium therethrough to transfer heat from the transformer, more specifically the winding 10, to the cooling medium. The plurality of cooling channels 24 may include a first cooling channel 24A which may be arranged within one of the gaps 20, e.g., within the first gap 20A, and at least a second cooling channel 24B which may be arranged within a further gap of the gaps 20, e.g., within the second gap 20B. The cooling medium is preferably a gas, preferably air, preferably ambient air.
  • The winding 10 may include any number of cooling channels 24. In other words, the number of cooling channels 24 described herein and shown in the Figures is only exemplary. The winding 10 may include more or less than the number of cooling channels 24 described herein and/or shown in the Figures.
  • In addition, the plurality of cooling channels 24 may include one or more cooling channels which are not arranged within a gap between winding portions. For instance, as shown in Fig. 1, at least one cooling channel 24C of the plurality of cooling channels 24 may be arranged below a lowermost winding portion 16C or above an uppermost winding portion. Alternatively, or additionally, at least one cooling channel of the plurality of cooling channels 24 may be arranged along a side of one or more of the winding portions 16 (not shown).
  • At least a section of the cooling channels 24 may extend annularly or semi-annularly along at least a section of the winding 10, as shown in Fig. 2.
  • At least some of the cooling channels 24, e.g., the first cooling channel 24A and the second cooling channel 24B, may each include at least one cooling medium inlet 28 for introducing the cooling medium into the respective cooling channel 24 and at least one cooling medium outlet 30 for allowing the cooling medium to exit from the respective cooling channel 24 (see Fig. 2). As an example, only one of the cooling medium inlets 28 and one of the cooling medium outlets 30 are depicted in Fig. 2.
  • The cooling medium inlets 28 and the cooling medium outlets 30 may be arranged in a side wall 34 of the transformer and/or the winding 10, as shown in Fig. 2.
  • The cooling channels 24 may be at least partially embedded within the electrically insulating material 22. The cooling channels 24 may be embedded between an inner layer 40 and an outer layer 42 of the electrically insulating material 22. The outer layer 42 may be arranged radially outside of the inner layer 40.
  • The cooling medium inlets 28 and/or the cooling medium outlets 30 may be arranged such that the cooling medium can enter the respective cooling channel 24 via the cooling medium inlets 28 and/or can exit the respective cooling channel 24 via the cooling medium outlets 30 substantially radially with respect to a circumference of the winding 10 and/or substantially perpendicularly to the longitudinal axis LA of the winding 10 and/or the transformer and/or the core and/or substantially perpendicularly to a winding axis WA of one or more of the winding portions 16, when the winding 10 is operatively installed in the transformer. Alternatively, the cooling medium may enter into and exit from the respective cooling channel 24 at other (non-radial) angles.
  • At least some of the cooling channels 24, preferably all of the cooling channels 24, may extend about at least 50%, preferably at least 60%, more preferably at least 70%, more preferably at least 80%, more preferably at least 90%, of a circumference of the core of the transformer, when the winding 10 is arranged around the core.
  • At least some of the cooling channels 24, e.g., the first cooling channel 24A and the second cooling channel 24B, preferably each of the plurality of cooling channels 24, may be part of and/or are connected to an open cooling circuit.
  • The cooling medium inlet(s) 28 and the cooling medium outlet(s) 30 of at least one of the cooling channels 24 may be positioned such that a plane, which extends substantially perpendicularly to a longitudinal axis of the winding 10 and/or the transformer and/or the core and/or substantially perpendicularly to a winding axis WA of one or more of the winding portions 16, when the winding 10 is operatively installed in the transformer, extends through the cooling medium inlet 28 and the cooling medium outlet 30 of the respective cooling channels 24. The plane may extend through a center of the cooling medium inlet 28 and a center of the cooling medium outlet 30. The plane may extend through the entire respective cooling channel 24, e.g., the entire first cooling channel 24A or the entire second cooling channel 24B.
  • The cooling medium inlets 28 and/or the cooling medium outlets 30 may be arranged in a section 50 of the side wall 34 of the transformer and/or a side wall 34 of the winding 10 which is substantially flat. Preferably, at least some of the cooling medium inlets 28 and/or the cooling medium outlets 30, preferably all of the cooling medium inlets 28 and/or the cooling medium outlets 30, are arranged in a dome structure 52 of the side wall 34 of the winding 10 and/or the transformer.
  • As shown in Figs. 3 and 4, the winding 10 may include at least one flow generating device 60. The flow generating device 60 may be configured to be powered, preferably electrically, to generate a forced convection flow of the cooling medium through the cooling channels 24. The flow generating device 60 may be arranged upstream from the cooling medium inlets 28 to blow the cooling medium, e.g., air, into the cooling medium inlets 28, as shown in Figs. 3 and 4. Alternatively, or additionally, the winding 10 may include at least one flow generating device, e.g., the flow generating device 60 mentioned above or a further flow generating device, which is configured and arranged to suck the cooling medium, e.g., air, out of the cooling medium outlets 30. In other words, the flow generating device may be arranged downstream from the cooling medium outlets 30. Alternatively, the flow of cooling medium may be caused by natural convection only.
  • The winding 10 may include at least one cooling medium supply device 64 configured to supply and distribute the cooling medium to each of the cooling medium inlets 28, as shown in Figs. 3 and 4. Alternatively, or additionally, the winding 10 may include at least one cooling medium outlet device 66 configured to collect and guide the cooling medium from each of the cooling medium outlets 30. For the sake of clarity, the cooling medium outlet device 66 has been omitted from Fig. 4.
  • The cooling medium supply device 64 may include a cooling medium supply device inlet 68, preferably a single cooling medium supply device inlet 68, which is fluidically connected or fluidically connectable to each cooling medium inlet 28. Alternatively, or additionally, the cooling medium outlet device 66 may include a cooling medium outlet device outlet 69, preferably a single cooling medium outlet device outlet 69, which is fluidically connected or fluidically connectable to each cooling medium outlet 30.
  • The cooling channels 24 may have any cross-sectional shape, e.g., round, oval, rectangular, polygonal, etc. As an example, the cooling channel 24 shown in Fig. 5A is rectangular. As shown in Figs. 5B and 5C, at least some of the cooling channels 24 may include one or more partitioning elements 72, e.g., one or more walls and/or one or more fins, configured to segment or divide a cross-sectional area of the respective cooling channel(s) 24 into two or more sub-areas or partitions 76, preferably three or more sub-areas or partitions.
  • Fig. 6 shows, in a schematic top view, a transformer 80 according to an embodiment of the present disclosure. The transformer 80 may include at least one core 82 and at least one winding 10 according to any of the embodiments described herein, e.g., the winding 10 of Figs. 1 to 4. The winding 10 may at least partially surround the core 82.

Claims (15)

  1. A winding (10) of a dry-type transformer (80), the winding (10) being configured to be arranged to at least partially surround a core (82) of the transformer (80), the winding (10) including:
    a first winding portion (16A) which includes an electrically conductive material;
    a second winding portion (16B) which includes an electrically conductive material,
    at least one third winding portion (16C) which includes an electrically conductive material;
    a first gap (20A) which is arranged at least partially between the first winding portion (16A) and the second winding portion (16B) and which is at least partially filled with electrically insulating material (22);
    at least a second gap (20B) which is arranged at least partially between the second winding portion (16B) and the third winding portion (16C) and which is at least partially filled with electrically insulating material (22);
    a plurality of cooling channels (24) configured to guide at least one cooling medium therethrough to transfer heat from the transformer (80) to the cooling medium, wherein the plurality of cooling channels (24) include a first cooling channel (24A) arranged within the first gap (20A) and at least a second cooling channel (24B) arranged within the second gap (20B),
    wherein the first cooling channel (24A) and the second cooling channel (24B) each include at least one cooling medium inlet (28) for introducing the cooling medium into the respective cooling channel (24) and at least one cooling medium outlet (30) for allowing the cooling medium to exit from the respective cooling channel (24),
    wherein the cooling medium inlets (28) and the cooling medium outlets (30) are arranged in a side wall (34) of the transformer (80) and/or a side wall (34) of the winding (10).
  2. The winding (10) according to claim 1, wherein the cooling medium inlets (28) and the cooling medium outlets (30) are arranged in a section (50) of the side wall (34) of the transformer and/or a side wall (34) of the winding (10) which is substantially flat, preferably wherein the cooling medium inlets (28) and the cooling medium outlets (30) are arranged in a dome structure (52) of the side wall (34) of the winding (10).
  3. The winding (10) according to claim 1 or 2, wherein the cooling medium is a gas, preferably air, preferably ambient air.
  4. The winding (10) according to any of claims 1 to 3, wherein the first cooling channel (24A) and the second cooling channel (24B), preferably each of the plurality of cooling channels (24), are part of and/or are connected to an open cooling circuit.
  5. The winding (10) according to any of claims 1 to 4, wherein a plane, which extends substantially perpendicularly to a longitudinal axis (LA) of the winding and/or the transformer (80) and/or the core (82) and/or substantially perpendicularly to a winding axis (WA) of the first winding portion (16A) and the second winding portion (16B), when the winding is operatively installed in the transformer (80), extends through the cooling medium inlet (28) and the cooling medium outlet (30) of the first cooling channel (24A) or the cooling medium inlet (28) and the cooling medium outlet (30) of the second cooling channel (24B).
  6. The winding (10) according to claim 5, wherein the plane extends through a center of the cooling medium inlet (28) and a center of the cooling medium outlet (30).
  7. The winding (10) according to claim 5 or 6, wherein the plane extends through the entire first cooling channel (24A) or the entire second cooling channel (24B).
  8. The winding (10) according to any of the preceding claims, further including:
    at least one cooling medium supply device (64) configured to supply and distribute the cooling medium to each of the cooling medium inlets (28);
    and/or
    at least one cooling medium outlet device (66) configured to collect and guide the cooling medium from each of the cooling medium outlets (30).
  9. The winding (10) according to claim 8, wherein:
    the cooling medium supply device (64) includes a cooling medium supply device inlet (68), preferably a single cooling medium supply device inlet (68), which is fluidically connected or fluidically connectable to each cooling medium inlet (28);
    and/or
    the cooling medium outlet device (66) includes a cooling medium outlet device outlet (69), preferably a single cooling medium outlet device outlet (69), which is fluidically connected or fluidically connectable to each cooling medium outlet (30).
  10. The winding (10) according to any of the preceding claims, wherein at least some of the cooling channels (24) include one or more partitioning elements (72) configured to segment a cross-sectional area of the respective cooling channel(s) (24) into two or more partitions (76), preferably three or more partitions (76).
  11. The winding (10) according to any of the preceding claims, wherein at least a section of the cooling channels (24) extends annularly or semi-annularly along at least a section of the winding.
  12. The winding (10) according to any of the preceding claims, further including at least one flow generating device (60) which can be powered, preferably electrically, to generate a forced convection flow of the cooling medium through the cooling channels (24).
  13. A transformer (80) which includes at least one core (82) and at least one winding (10) according to any of the preceding claims which at least partially surrounds the core (82).
  14. A method of manufacturing a winding (10) of a transformer (80), preferably the winding (10) of any of claims 1 to 12, the winding (10) being configured to be arranged to at least partially surround a core (82) of the transformer (80), including:
    arranging a first winding portion (16A) which includes an electrically conductive material;
    arranging a second winding portion (16B) which includes an electrically conductive material such that a first gap (20A) is arranged at last partially between the first winding portion (16A) and the second winding portion (16B);
    arranging at least one third winding portion (16C) which includes an electrically conductive material such that a second gap (20B) is arranged at last partially between the second winding portion (16B) and the third winding portion (16C);
    providing a plurality of cooling channels (24) configured to guide at least one cooling medium therethrough to transfer heat from the transformer (80) to the cooling medium, wherein the plurality of cooling channels (24) include a first cooling channel (24A) arranged within the first gap (20A) and at least a second cooling channel (24B) arranged within the second gap (20B), wherein the first cooling channel (24A) and the second cooling channel (24B) each include at least one cooling medium inlet (28) for introducing the cooling medium into the respective cooling channel (24) and at least one cooling medium outlet (30) for allowing the cooling medium to exit from the respective cooling channel (24), wherein the cooling medium inlets (28) and the cooling medium outlets (30) are arranged in a side wall (34) of the winding (10) and/or the transformer (80);
    filling the first gap (20A) and the second gap (20B) at least partially with an electrically insulating material (22).
  15. A method of operating a dry-type transformer (80), preferably the transformer (80) of claim 13, the transformer (80) including at least one core (82) and at least one winding (10) at least partially surrounding the core (82), the winding (10) including a first winding portion (16A) which includes an electrically conductive material, a second winding portion (16B) which includes an electrically conductive material, at least one third winding portion (16C) which includes an electrically conductive material, a first gap (20A) which is arranged at least partially between the first winding portion (16A) and the second winding portion (16B) and which is at least partially filled with electrically insulating material, at least a second gap (20B) which is arranged at least partially between the second winding portion (16B) and the third winding portion (16C) and which is at least partially filled with electrically insulating material, and a plurality of cooling channels (24) configured to guide at least one cooling medium therethrough to transfer heat from the transformer (80) to the cooling medium, wherein the plurality of cooling channels (24) include a first cooling channel (24A) arranged within the first gap (20A) and at least a second cooling channel (24B) arranged within the second gap (20B), the method including:
    introducing the cooling medium into the first cooling channel (24A) through at least one cooling medium inlet (28) of the first cooling channel (24A) and into the second cooling channel (24B) through at least one cooling medium inlet (28) of the second cooling channel (24B), the cooling medium inlets (28) being arranged in a side wall (34) of the transformer (80) and/or a side wall (34) of the winding (10);
    discharging the cooling medium from the first cooling channel (24A) through at least one cooling medium outlet (30) of the first cooling channel (24A) and from the second cooling channel (24B) through at least one cooling medium outlet (30) of the second cooling channel (24B), the cooling medium outlets (30) being arranged in a side wall (34) of the transformer (80) and/or a side wall (34) of the winding (10).
EP24382339.0A 2024-03-28 2024-03-28 Winding, transformer, method of manufacturing a winding of a transformer, and method of operating a dry-type transformer Pending EP4625450A1 (en)

Priority Applications (2)

Application Number Priority Date Filing Date Title
EP24382339.0A EP4625450A1 (en) 2024-03-28 2024-03-28 Winding, transformer, method of manufacturing a winding of a transformer, and method of operating a dry-type transformer
PCT/EP2025/058582 WO2025202467A1 (en) 2024-03-28 2025-03-28 Winding, transformer, method of manufacturing a winding of a transformer, and method of operating a dry-type transformer

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
EP24382339.0A EP4625450A1 (en) 2024-03-28 2024-03-28 Winding, transformer, method of manufacturing a winding of a transformer, and method of operating a dry-type transformer

Publications (1)

Publication Number Publication Date
EP4625450A1 true EP4625450A1 (en) 2025-10-01

Family

ID=90717131

Family Applications (1)

Application Number Title Priority Date Filing Date
EP24382339.0A Pending EP4625450A1 (en) 2024-03-28 2024-03-28 Winding, transformer, method of manufacturing a winding of a transformer, and method of operating a dry-type transformer

Country Status (2)

Country Link
EP (1) EP4625450A1 (en)
WO (1) WO2025202467A1 (en)

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH0766048A (en) * 1993-08-23 1995-03-10 Toshiba Corp Cooling structure for stationary induction device winding
JPH08115823A (en) * 1994-10-19 1996-05-07 Toshiba Corp Static induction device winding and method of manufacturing the same
EP0766273A2 (en) * 1995-09-28 1997-04-02 Makoto Yamamoto Transformer structure
CN103219136A (en) * 2013-04-26 2013-07-24 江苏上能新特变压器有限公司 Phase-shift rectification dry-type transformer
US20200388430A1 (en) * 2017-03-10 2020-12-10 Abb Schweiz Ag Non-liquid immersed transformers with improved coil cooling

Family Cites Families (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3419834A (en) * 1966-03-24 1968-12-31 Ian C. Mckechnie Electrical coils
JPS574107A (en) * 1980-06-10 1982-01-09 Sumitomo Electric Ind Ltd Cooler of refrigerant of coil for electrical machinery and apparatus

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH0766048A (en) * 1993-08-23 1995-03-10 Toshiba Corp Cooling structure for stationary induction device winding
JPH08115823A (en) * 1994-10-19 1996-05-07 Toshiba Corp Static induction device winding and method of manufacturing the same
EP0766273A2 (en) * 1995-09-28 1997-04-02 Makoto Yamamoto Transformer structure
CN103219136A (en) * 2013-04-26 2013-07-24 江苏上能新特变压器有限公司 Phase-shift rectification dry-type transformer
US20200388430A1 (en) * 2017-03-10 2020-12-10 Abb Schweiz Ag Non-liquid immersed transformers with improved coil cooling

Also Published As

Publication number Publication date
WO2025202467A1 (en) 2025-10-02

Similar Documents

Publication Publication Date Title
US8866351B2 (en) Cooling arrangement for an electric machine
US10998795B2 (en) Cooling schemes and methods for cooling tower motors
US8053938B2 (en) Enhanced motor cooling system
US3597645A (en) Liquid cooling system for stacks of stator laminations of electrical machinery
US6552545B2 (en) Gradient coil with direct cooling
CN102696082B (en) Transformer with separator and cooling method thereof
US12308159B2 (en) Transformer cooling system and transformer installation
CN112448524A (en) Motor and vehicle
US10587167B2 (en) Rotor assembly having improved cooling path
CN101548348A (en) Cooling system for dry-type air-core reactors
EP4625450A1 (en) Winding, transformer, method of manufacturing a winding of a transformer, and method of operating a dry-type transformer
EP3312856A1 (en) Transformer with winding support having cooling functionality
CN113557581A (en) Device for cooling coil
KR102888549B1 (en) transformer equipment
KR20260017449A (en) A transformer arrangement having an air duct element, an air duct element, and a cooling system for cooling the transformer.
KR102652386B1 (en) Gas insulated transformer
FI117776B (en) Throttle
US12451753B2 (en) Electric machine with directly cooled windings
HK1252708A1 (en) Transformer with winding support having cooling functionality
SE511360C2 (en) Air-cooled cable-wound power transformer
SE511374C2 (en) Air-cooled cable-wound power transformer

Legal Events

Date Code Title Description
PUAI Public reference made under article 153(3) epc to a published international application that has entered the european phase

Free format text: ORIGINAL CODE: 0009012

STAA Information on the status of an ep patent application or granted ep patent

Free format text: STATUS: THE APPLICATION HAS BEEN PUBLISHED

AK Designated contracting states

Kind code of ref document: A1

Designated state(s): AL AT BE BG CH CY CZ DE DK EE ES FI FR GB GR HR HU IE IS IT LI LT LU LV MC ME MK MT NL NO PL PT RO RS SE SI SK SM TR

STAA Information on the status of an ep patent application or granted ep patent

Free format text: STATUS: REQUEST FOR EXAMINATION WAS MADE

17P Request for examination filed

Effective date: 20260303