Transformer coils and their manufacturing methods, transformers

Abstract

This invention provides a transformer coil, its manufacturing method, and a transformer. The transformer coil includes an inner support member and multiple coils wound around the inner support member. The multiple coils include two coils spaced a predetermined distance apart in the extending direction of the inner support member. Each coil includes a conductor and an insulation layer. The transformer coil also includes multiple anti-slip members. One of the anti-slip members includes a first connecting section and a second connecting section connected to a first end of the first connecting section. The first connecting section of the anti-slip member is disposed between the inner support member and the coils and is pressed against the inner support member by the conductor and insulation layer of the coils. The second connecting section of the anti-slip member extends radially along the coils and supports the coils to prevent slippage. This transformer is simple to manufacture and has high reliability.

Description

Technical Field

[0001] This invention relates to the field of power generation equipment, and in particular to a transformer coil, its manufacturing method, and a transformer. Background Technology

[0002] Epoxy resin cast transformers are widely used in power distribution systems due to their advantages such as good insulation performance, high mechanical strength, and convenient maintenance. The coils of this type of transformer are typically made using foil winding or wire winding methods, and after winding, they are molded and cured with epoxy resin. Before the epoxy resin is fully cured, the coil cores or winding units inside the coil have not yet formed a stable overall structure.

[0003] During production, transportation, or casting, if the coil experiences axial sliding, partial sagging, or complete drop, it can easily cause changes in the relative positions of the winding units within the coil, resulting in deviations in the originally set interlayer, inter-coil, or end insulation distances. This can lead to uneven local electric field distribution, reduced insulation margin, and consequently, increased risks of electrical failures such as partial discharge and insulation breakdown, affecting the operational reliability of the transformer. Summary of the Invention

[0004] To at least address some of the aforementioned problems, this invention proposes a transformer coil, its manufacturing method, and a transformer.

[0005] According to a first aspect of the present invention, a transformer coil is provided. The transformer coil includes an inner support member and a plurality of coils wound outside the inner support member. The plurality of coils includes two coils spaced apart by a predetermined distance in the extending direction of the inner support member. The two coils include conductors and insulating layers. The transformer coil also includes a plurality of anti-slip members. One of the anti-slip members includes a first connecting section and a second connecting section connected to a first end of the first connecting section. The first connecting section of the anti-slip member is disposed between the inner support member and the coils and is pressed against the inner support member by the conductors and insulating layers of the coils. The second connecting section of the anti-slip member extends radially along the coils and supports the coils to prevent the coils from slipping.

[0006] Optionally, the first connecting section is provided with an anti-slip structure on the side facing the inner support member, and the anti-slip structure abuts against the inner support member.

[0007] Optionally, the inner support includes a fiberglass mesh, and the anti-slip structure includes a serrated protrusion structure, a portion of which is embedded in the mesh openings of the fiberglass mesh and in line contact with the glass mesh.

[0008] Optionally, the length of the first connecting segment extending along the inner support member is in the range of 30 mm to 50 mm.

[0009] Optionally, multiple anti-slip elements are provided at circumferential intervals along the disc.

[0010] Optionally, the thickness of the second connecting segment in the extension direction of the inner support is less than the height of the interval between two adjacent wire discs in the extension direction of the inner support.

[0011] Optionally, the inner support, anti-slip component, and spool are all covered with a protective material for the anti-slip component that has been cast and cured. The anti-slip component is made of the same material as the protective material, or the anti-slip component is made of a material that is relatively inert to the protective material.

[0012] Optionally, the anti-slip component is made of at least one of epoxy resin, quartz, or ceramic, or it is made of glass fiber molded component.

[0013] According to a second aspect of the present invention, a transformer is provided, characterized in that the transformer includes the transformer coil described above.

[0014] According to a third aspect of the present invention, a method for manufacturing a transformer coil is provided, comprising: laying an inner layer support on the surface of a mold; providing a plurality of anti-slip members outside the inner layer support, such that a portion of a first connecting section of the anti-slip members contacts the inner layer support; winding a conductor and an insulating layer outside the inner layer support to form a coil; pouring a protective material into the space between the mold, the inner layer support, the coil, and the anti-slip members, and allowing the protective material to cure.

[0015] Optionally, when the conductor and insulation layer are wound around the inner support to form a coil, the first connecting section of the anti-slip member is located between the inner winding of the coil and the inner support, and the second connecting section of the anti-slip member is located below the bottom surface of the coil.

[0016] In this invention, the transformer coil is pressed and fixed to the inner support by the coil through a first connecting section of an anti-slip member between the coil and the inner support member during the winding of the conductor and insulation layer. The second connecting section of the anti-slip member forms a radially extending support structure for the coil, thereby achieving support and positioning of the coil. During the subsequent transportation, collision, erection, and pre-casting curing of the coil, the risk of the coil sliding along the extension direction of the inner support member or the winding partially falling is reduced, and the insulation distance within the coil is prevented from changing, thereby improving the insulation reliability of the transformer coil. Attached Figure Description

[0017] Preferred embodiments of the present invention will now be described in detail with reference to the accompanying drawings, which will make the above and other features and advantages of the present invention more apparent to those skilled in the art. In the drawings: Figure 1 This is a schematic diagram of the structure of a transformer coil provided in an embodiment of the present invention.

[0018] Figure 2This is a first-view perspective three-dimensional schematic diagram of an anti-slip component for a transformer coil provided in an embodiment of the present invention.

[0019] Figure 3 This is a second-view perspective three-dimensional schematic diagram of an anti-slip component for a transformer coil provided in an embodiment of the present invention.

[0020] Figure 4 A partial cross-sectional view of the anti-slip component at the junction of the transformer coil coil disc with the mold and inner support component, provided in an embodiment of the present invention; Figure 5 This is a schematic flowchart illustrating the steps of a method for manufacturing a transformer coil according to an embodiment of the present invention.

[0021] The accompanying figure is labeled as follows: 10. Mold; 20. Inner support component; 30. Line disc; 40. Anti-slip component; 41. First connecting section; 411. Anti-slip structure; 42. Second connecting section.

[0022] S501: Lay an inner support layer on the surface of the mold.

[0023] S502: Multiple anti-slip elements are provided outside the inner support element, and a portion of the first connecting section of the anti-slip element contacts the inner support element.

[0024] S503: A conductor and an insulating layer are wound around the inner support to form a coil.

[0025] S504: Pour protective material into the mold and the spaces of the inner support, filament, and anti-slip components, and allow the protective material to cure. Detailed Implementation

[0026] To make the objectives, technical solutions, and advantages of the present invention clearer, the following embodiments are provided to further illustrate the present invention in detail.

[0027] Embodiments of the present invention provide a transformer coil used in a transformer, which may be a dry-type transformer cast with epoxy resin. A dry-type transformer includes multiple coils; for example, high-voltage coils and low-voltage coils can both be collectively referred to as coils. Figure 1 As shown, taking a high-voltage coil as an example, a high-voltage coil of one phase includes two or more coils 30. There is a gap between two adjacent coils 30. Usually, the gap is filled with epoxy resin to achieve insulation protection. However, during the manufacturing process, the coils 30 may slip, which will lead to a deterioration in the insulation effect.

[0028] The transformer coil of this embodiment includes an inner support member 20, multiple coils 30 wound around the inner support member 20, and multiple anti-slip members 40. The multiple coils 30 include two coils 30 spaced apart at a predetermined distance in the extending direction of the inner support member 30. Each coil 30 includes a conductor and an insulation layer. One of the multiple anti-slip members 40 includes a first connecting section 41 and a second connecting section 42 connected to a first end of the first connecting section 41. The first connecting section 41 of the anti-slip member 40 is disposed between the inner support member 20 and the coils 30 and is pressed against the inner support member 20 by the conductor and insulation layer of the coils 30. The second connecting section 42 of the anti-slip member 40 extends radially along the coils 30 and supports the coils 30 to prevent slippage. This solves the problem that the coils 30 may slip entirely or partially during the transformer coil manufacturing process, causing changes in the internal insulation distance of the coil and increasing the risk of electrical failures such as partial discharge and insulation breakdown. By setting the first connecting section 41 of the anti-slip member 40 between the coil 30 and the inner support member 20, the coil 30 is pressed and fixed onto the inner support member 20 during the winding process. The second connecting section 42 of the anti-slip member 40 forms a radially extending support structure for the coil 30, thereby achieving support and positioning of the coil 30. In the subsequent production processes of coil transfer, collision, erection, and before casting and curing, the risk of the coil 30 sliding or falling locally along the extension direction of the inner support member can be reduced, and the change of insulation distance in the coil can be avoided, thereby improving the insulation reliability of the transformer coil.

[0029] The aforementioned predetermined distance can be set according to the insulation distance required by the transformer, and there are no restrictions on it.

[0030] In some alternative embodiments, the first connecting section 41 of the anti-slip member 40 is provided with an anti-slip structure 411 on the side facing the inner support member 20, and the anti-slip structure 411 abuts against the inner support member 20. The anti-slip structure 411 not only fixes the anti-slip member 40 to the inner support member 20 by the clamping force of the coil 30 winding, but also enhances the frictional engagement between the anti-slip member 40 and the inner support member 20.

[0031] In this embodiment, the inner support member 20 can be a glass fiber mesh. During processing, the glass fiber mesh is wound around the surface of the mold 10. Through the cooperation of the anti-slip structure 411 and the glass fiber mesh, the anti-slip ability between the first connecting section 41 and the inner support member 20 can be improved, so that the anti-slip member 40 can still maintain a stable position when subjected to the weight of the coil 30, transportation vibration or additional load during the coil erection process, thereby further enhancing the supporting effect of the anti-slip member 40 on the coil 30.

[0032] Optionally, such as Figure 2As shown, the anti-slip structure 411 may include a serrated protrusion structure, a portion of which is embedded within the mesh of the fiberglass mesh and in line contact with the fiberglass mesh. The serrated protrusion structure may be distributed along the side of the first connecting section 41 toward the inner support member 20, or it may be configured as a continuous toothed shape, intermittent toothed shape, or an uneven rough structure depending on the surface morphology of the inner support member 20, as long as it can increase surface roughness and improve friction. This serrated protrusion structure can form a more reliable interlocking or frictional contact with the inner support member 20, and compared to a flat surface contact, it can more effectively resist the slippage of the anti-slip member 40 relative to the inner support member 20, thereby improving the installation stability and support reliability of the anti-slip member 40.

[0033] Optionally, the length of the first connecting segment 41 extending along the inner support member 20 is in the range of 30 mm to 50 mm. This length range allows the first connecting segment 41 to have sufficient contact area so that it can be pressed against the inner support member 20 by the coil winding 30, without excessively occupying the internal space of the coil, and providing sufficient friction to ensure reliable support.

[0034] In some embodiments, such as Figure 1 As shown, multiple anti-slip elements 40 are spaced apart along the circumference of the coil 30. These anti-slip elements 40 can be evenly arranged along the circumference of the coil, or they can be non-uniformly arranged according to the weight of the coil 30, the coil diameter, the location of concentrated stress, or process requirements. This provides multi-point support to the coil 30, preventing it from tilting, sinking, or deforming due to stress only in localized areas. This improves the overall stability of the coil 30 and helps maintain consistent insulation distances between coils 30, thereby enhancing the uniformity of circumferential support.

[0035] Optionally, the inner support 20, the anti-slip component 40, and the coil 30 are all covered with a protective material for the anti-slip component 40, which is then cast and cured. The anti-slip component 40 can be made of the same material as the protective material, or it can be a material that is relatively inert to the protective material. The protective material (also known as the insulating material) can be an epoxy resin casting material, which, after casting, covers the inner support 20, the anti-slip component 40, and the coil 30, and forms an integral insulating structure after curing. The material that is relatively inert to the protective material can be understood as an insulating material that is fused into the epoxy resin casting material and will not deform when heated or undergo an adverse chemical reaction with the epoxy resin, such as ceramics.

[0036] By casting and curing the anti-slip component 40 with protective material, the anti-slip component 40 can be integrated with the coil 30 and the inner support component 20 into a stable whole after the coil is formed, reducing the risk of the anti-slip component 40 loosening or falling off during long-term operation. When the material of the anti-slip component 40 is the same as the protective material or is relatively inert to the protective material, the risk of insulation defects caused by material incompatibility, thermal deformation, or reaction can be reduced, thereby improving the long-term operational reliability of the cast-resin transformer coil.

[0037] For example, the anti-slip component 40 can be made of at least one of epoxy resin, quartz, or ceramic, or it can be a glass fiber molded component. The anti-slip component 40 is made of an insulating material that can stably bond with the epoxy resin casting material, is not easily deformed by heat, and does not adversely react with the casting material. The anti-slip component 40 made of the above materials can meet the requirements for insulation performance, heat resistance, and structural strength. For example, epoxy resin is easy to fuse with epoxy resin casting materials; quartz, ceramic, or glass fiber molded components have good insulation and dimensional stability, and can maintain their supporting shape under casting curing and transformer coil operating conditions, thereby improving the reliability of the anti-slip structure.

[0038] In some alternative embodiments, the thickness of the second connecting segment 42 in the extending direction of the inner support member 20 is less than the height of the gap between two adjacent coils 30 in the extending direction of the inner support member. The second connecting segment 42 may be located below the bottom surface of the coil 30 and extend into the gap area between two adjacent coils 30 to provide support for the upper coil 30. Due to the smaller thickness of the second connecting segment 42, it has less impact on the impregnation of the protective material during casting, which helps to ensure sufficient impregnation of the protective material and thus guarantees the insulation performance.

[0039] Embodiments of the present invention also provide a transformer comprising the aforementioned transformer coil. This transformer maintains the insulation distance consistent with the original design intent, resulting in more reliable performance.

[0040] Embodiments of the present invention also provide a method for manufacturing a high-voltage coil of a transformer coil. This manufacturing method may include the following steps: Step S501: Lay the inner support component 20 on the surface of the mold 10.

[0041] Step S502: A plurality of anti-slip members 40 are provided outside the inner support member 20, and a portion of the first connecting section 41 of the anti-slip member 40 is made to contact the inner support member 20.

[0042] Step S503: Wind conductors and insulation layers around the inner support 20 to form a coil 30.

[0043] Step S504: Pour protective material into the space of mold 10, inner support 20, line 30 and anti-slip part 40 and allow the protective material to cure.

[0044] Using the above manufacturing method, the positioning of the anti-slip component 40 can be completed simultaneously during the high-voltage coil winding and casting stages, allowing the anti-slip component 40 to be pressed and fixed during the formation of the coil 30 by the conductor and insulation layer. Subsequently, by pouring protective material and curing, the anti-slip component 40, the inner support component 20, and the coil 30 can be fixed into an integral structure. This method eliminates the need for extensive filling of glass mesh or resin spacers between the coils 30, simplifying the processing operation and reducing the risk of incomplete filling, incomplete impregnation, or excessive compression of the insulation structure.

[0045] In step 503, when the conductor and insulation layer are wound around the inner support member 20 to form the coil 30, the first connecting segment 41 of the anti-slip member 40 can be positioned between the inner winding of the coil 30 and the inner support member 20, and the second connecting segment 42 of the anti-slip member 40 can be positioned below the bottom surface of the coil 30. After the conductor and insulation layer are wound, the inner winding of the coil 30 presses the first connecting segment 41 against the inner support member 20, while the second connecting segment 42 provides support to the coil 30 from below the bottom surface. This allows the anti-slip member 40 to be fixed using the clamping force generated during the winding process of the coil 30 itself, without requiring additional complex connection structures. Simultaneously, the second connecting segment 42, located below the bottom surface of the coil 30, can directly withstand any potential sliding or falling tendency of the coil 30. Therefore, during transportation, impact, flipping, or erection before the transformer coil is cured, the movement of the coil 30 is reliably restricted, maintaining a stable internal insulation distance within the coil.

[0046] During the winding process, an inner support member 2 can be laid outside the mold 10, forming a cylindrical structure extending vertically. Then, an anti-slip member 40 is placed at the location where the coil 30 needs to be wound, partially embedded in the mesh of the inner support member 20. The anti-slip member 40 is positioned by hand or other means. Then, one section of the conductor of the coil 30 is fixed to the inner support member 20, and the conductor is wound around it, pressing it against the first connecting section 41 of the anti-slip member 40, thus fixing the first connecting section 41. After winding a certain distance, another anti-slip member 40 can be placed, and this process is repeated until all the circumferential anti-slip members 40 are placed, and then winding continues. After completing the winding of one coil, another coil 30 can be wound on the inner support member 12 until all coils 30 are wound.

[0047] In summary, this invention provides an anti-slip member 40 with a first connecting section 41 and a second connecting section 42 between the inner support member 20 and the coil 30. During winding, the anti-slip member 40 is pressed firmly by the coil 30, and the second connecting section 42 supports the coil 30, effectively preventing the coil 30 from slipping. This solution has a simple structure, is easy to implement with the high-voltage coil winding process, and can be combined with the casting and curing process to form a stable whole. It has the advantages of low cost, high reliability, and minimal impact on the original coil structure.

[0048] Furthermore, by limiting the length of the first connecting segment 41 of the anti-slip member 40 along the extension direction of the inner support member to within the range of 30 to 50 mm, both fixing reliability and structural compactness can be achieved. On the one hand, the first connecting segment 41 can obtain a sufficient pressing contact area, increasing the load-bearing capacity of the anti-slip member 40; on the other hand, it can prevent the first connecting segment 41 from being too large, thus affecting the winding of the coil 30, insulation arrangement, or flow of the casting material. By making the thickness of the inner support member of the second connecting segment 42 in the extension direction less than the height of the interval between the inner support members of two adjacent coils 30 in the extension direction, it can be prevented that the second connecting segment 42 is too thick and squeezes the adjacent coils 30 or damages the insulation interval between the coils 30. At the same time, the second connecting segment 42 can still provide the necessary support force, thereby achieving anti-slip and anti-falling effects without changing or substantially changing the original insulation design space. The anti-slip component 40 with this structure solves the problems associated with methods such as inserting glass mesh blocks into the gaps between the wire cakes 30 after winding, which involve complex glass mesh filling operations and potential discharge or partial discharge hazards due to incomplete resin impregnation; and the use of resin spacers which can lead to incomplete filling, easy detachment, or damage to insulation due to overly tight filling. Furthermore, the method of this embodiment does not require additional insulation distance or thickness, thus eliminating the need for increased material costs and product size.

[0049] It should be noted that the transformer coil in the embodiments of the present invention can be a foil-wound or wire-wound winding, and there is no limitation thereto.

[0050] The above are merely preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A transformer coil, characterized in that, The transformer coil includes an inner support member (20) and a plurality of coils (30) wound around the inner support member (20). The plurality of coils (30) includes two coils (30) spaced apart at a predetermined distance in the extending direction of the inner support member (30). The two coils (30) include conductors and insulation layers. The transformer coil also includes a plurality of anti-slip members (40). One of the anti-slip members (40) includes a first connecting section (41) and a second connecting section (42) connected to a first end of the first connecting section (41). The first connecting section (41) of the anti-slip member (40) is disposed between the inner support member (20) and the coils (30) and is pressed against the inner support member (20) by the conductors and insulation layers of the coils (30). The second connecting section (42) of the anti-slip member (40) extends radially along the coils (30) and supports the coils (30) to prevent the coils (30) from sliding.

2. The transformer coil according to claim 1, characterized in that, The first connecting section (41) is provided with an anti-slip structure (411) on the side facing the inner support member (20), and the anti-slip structure (411) abuts against the inner support member (20).

3. The transformer coil according to claim 2, characterized in that, The inner support (20) includes a glass fiber mesh, and the anti-slip structure (411) includes a serrated protrusion structure, a portion of which is embedded in the mesh openings of the glass fiber mesh and in line contact with the glass mesh.

4. The transformer coil according to any one of claims 1-3, characterized in that, The length of the first connecting segment (41) along the extension direction of the inner support member (20) is in the range of 30 mm to 50 mm.

5. The transformer coil according to any one of claims 1-3, characterized in that, A plurality of anti-slip elements (40) are provided at circumferential intervals along the line disc (30).

6. The transformer coil according to any one of claims 1-3, characterized in that, The thickness of the second connecting segment (42) in the extension direction of the inner support (20) is less than the height of the interval between two adjacent wire discs (30) in the extension direction of the inner support.

7. The transformer coil according to any one of claims 1-3, characterized in that, The inner support (20), the anti-slip component (40) and the line disc (30) are all covered with a protective material for casting and curing the anti-slip component (40). The material of the anti-slip component (40) is the same as that of the protective material, or the material of the anti-slip component (40) is an inert material relative to the protective material.

8. The transformer coil according to claim 7, characterized in that, The anti-slip component (40) is made of at least one of epoxy resin, quartz, or ceramic, or the anti-slip component (40) is a glass fiber molded component.

9. A transformer, characterized in that, The transformer includes the transformer coil as described in any one of claims 1-8.

10. A method for manufacturing a transformer coil, characterized in that, include: An inner support component (20) is laid on the surface of the mold (10); A plurality of anti-slip members (40) are provided outside the inner support member (20), and a portion of the first connecting section (41) of the anti-slip member (40) is in contact with the inner support member (20); A conductor and an insulating layer are wound around the inner support (20) to form a coil (30); Pour protective material into the space of the mold (10) and the inner support (20), the filament (30) and the anti-slip member (40) and allow the protective material to cure.

11. The method according to claim 10, characterized in that, When the conductor and insulation layer are wound around the inner support member (20) to form a coil (30), the first connecting section (41) of the anti-slip member (40) is located between the inner winding of the coil (30) and the inner support member (20), and the second connecting section (42) of the anti-slip member (40) is located below the bottom surface of the coil (30).

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