Winding assembly, dry type transformer and method for manufacturing winding assembly

Abstract

The invention provides a winding assembly, a dry-type transformer and a method for manufacturing the winding assembly, and belongs to the technical field of transformers. The winding assembly comprises a supporting cylinder which comprises a cylinder body which extends along a first direction and is provided with an outer wall and an inner wall; the first flange and the second flange are arranged at the first end and the second end, opposite to each other in the first direction, of the barrel correspondingly. The coil is wound on the outer wall of the barrel in the first direction; and the packaging insulators are used for packaging the supporting barrel and the coils, so that the packaging insulators are filled between the coils and the outer wall of the barrel body, between the coils, between the coils and the first flange, between the coils and the second flange, on the outer surface of the first flange and on the inner wall of the barrel body.

Description

Technical Field

[0001] The present application relates to the technical field of transformers, and in particular, to a winding assembly, a dry-type transformer, and a method for manufacturing a winding assembly. Background Art

[0002] Vacuum Cast Coils (VCC) are currently the main products of dry-type transformers. For the insulation of the winding assembly in a dry-type transformer, it is usually necessary to encapsulate it. For example, epoxy resin casting is widely used as an insulation method for dry-type transformers.

[0003] However, the encapsulating insulator of the current winding assembly is prone to insulation failure caused by cracking and surface tracking failure caused by water absorption under extreme and special environments (such as high temperature, low temperature, shock, outdoor use environment). Therefore, there is an urgent need for a winding assembly that has high crack resistance and weather resistance under extreme and special environments. Summary of the Invention

[0004] The present application provides a winding assembly that has high crack resistance and weather resistance under extreme and special environments.

[0005] In one aspect of the present application, a winding assembly is provided, including: a support cylinder, including: a cylinder body extending in a first direction, the cylinder body having an outer wall and an inner wall; and a first flange and a second flange, the first flange and the second flange are respectively disposed at the first end and the second end of the cylinder body opposite to each other in the first direction; a coil wound around the outer wall of the cylinder body in the first direction; and an encapsulating insulator encapsulating the support cylinder and the coil, such that the space between the coil and the outer wall of the cylinder body, between the coils, between the coil and the first flange, between the coil and the second flange, the outer surface of the first flange, and the inner wall of the cylinder body are all filled with the encapsulating insulator.

[0006] In another aspect of the present application, a dry-type transformer is provided, including the winding assembly in the above embodiment.

[0007] In still another aspect of the present application, a method for manufacturing the winding assembly in the above embodiment is provided, including: installing the cylinder body of the support cylinder on the second flange of the support cylinder; sleeving the installed cylinder body and the second flange on an inner mold; winding the coil around the outer wall of the cylinder body; installing the first flange of the support cylinder on the cylinder body; loading the support cylinder wound with the coil into an outer mold and pouring with a liquid encapsulating insulating material to form an encapsulating insulator, wherein the encapsulating insulator encapsulates the support cylinder and the coil, such that the space between the coil and the outer wall of the cylinder body, between the coils, between the coil and the first flange, between the coil and the second flange, the outer surface of the first flange, and the inner wall of the cylinder body are all filled with the encapsulating insulator; and taking out the poured and cured winding assembly from the outer mold and removing the inner mold.

[0008] The above is an overview of the present application. There may be simplifications, generalizations, and omissions of details. Therefore, those skilled in the art should recognize that this part is only illustrative and is not intended to limit the scope of the present application in any way. This overview section is neither intended to identify the key features or essential features of the claimed subject matter nor to be used as an aid in determining the scope of the claimed subject matter. Description of the Drawings

[0009] The above and other features of the present application will be more fully and clearly understood by reference to the following description, the appended claims, and the accompanying drawings. It can be understood that these drawings only depict several embodiments of the present application and should not be considered as limiting the scope of the present application. By using the drawings, the present application will be more clearly and detailedly described.

[0010] Figure 1 Schematically shows a schematic structural view of a winding assembly according to an embodiment of the present application.

[0011] Figure 2 Schematically shows Figure 1 a cross-sectional view of the winding assembly of

[0012] Figure 3 Schematically shows a schematic structural view of a support cylinder according to an embodiment of the present application.

[0013] Figure 4 Schematically shows a schematic structural view of a first flange according to an embodiment of the present application.

[0014] Figure 5 Schematically shows a schematic structural view of a second flange according to an embodiment of the present application.

[0015] Figure 6 Schematically shows a schematic structural view of a test tool for simulating the application of a fixing force according to an embodiment of the present application.

[0016] Figure 7 Schematically shows a flowchart of a method for manufacturing a winding assembly according to an embodiment of the present application. Detailed Description of the Embodiments

[0017] The embodiments of the technical solution of the present application will be described in detail below with reference to the drawings. The following embodiments are only used to more clearly illustrate the technical solution of the present application and, therefore, are only examples and should not be used to limit the protection scope of the present application.

[0018] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the technical field to which this application belongs; the terms used herein are for the purpose of describing specific embodiments only and are not intended to limit this application; the terms "including" and "having" and any variations thereof in the specification and claims of this application and the above drawings are intended to cover non-exclusive inclusion.

[0019] In the description of the embodiments of this application, technical terms such as "first" and "second" are only used to distinguish different objects and cannot be understood as indicating or implying relative importance or implicitly specifying the quantity, specific order, or primary-secondary relationship of the indicated technical features. In the description of the embodiments of this application, the meaning of "a plurality" is more than two, unless otherwise specifically and clearly defined.

[0020] Referring to "embodiments" herein means that the specific features, structures, or characteristics described in connection with the embodiments can be included in at least one embodiment of this application. The phrase appearing in various positions in the specification does not necessarily refer to the same embodiment, nor is it an independent or alternative embodiment mutually exclusive with other embodiments. Those skilled in the art will explicitly and implicitly understand that the embodiments described herein can be combined with other embodiments.

[0021] In the description of the embodiments of this application, the term "and / or" is merely a description of the association relationship of associated objects, indicating that three relationships can exist. For example, A and / or B can represent: A exists alone, A and B exist simultaneously, and B exists alone. In addition, the character " / " herein generally represents an "or" relationship between the associated objects before and after.

[0022] In the description of the embodiments of this application, the term "a plurality" refers to more than two (including two). Similarly, "multiple groups" refers to more than two groups (including two groups), and "multiple pieces" refers to more than two pieces (including two pieces).

[0023] In the description of the embodiments of this application, the orientation or positional relationship indicated by technical terms such as "center", "longitudinal", "transverse", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc. is based on the orientation or positional relationship shown in the drawings. It is only for the convenience of describing the embodiments of this application and simplifying the description, and does not indicate or imply that the indicated device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the embodiments of this application.

[0024] In the description of the embodiments of the present application, unless otherwise clearly specified and limited, technical terms such as "installation", "connection", "linkage", and "fixation" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral one; it can also be a mechanical connection or an electrical connection; it can be directly connected or indirectly connected through an intermediate medium, and it can be the communication inside two components or the interaction relationship between two components. For those of ordinary skill in the art, the specific meanings of the above terms in the embodiments of the present application can be understood according to specific circumstances.

[0025] In the description of the embodiments of the present application, flowcharts are used to illustrate the operations performed by the systems according to the embodiments of the present disclosure. It should be understood that the operations before or after may not necessarily be executed precisely in sequence. On the contrary, the steps can be processed in reverse order or simultaneously. At the same time, other operations can also be added to these processes, or one or more steps can be removed from these processes.

[0026] Currently, for the insulation of the winding assembly in a dry-type transformer, it is usually necessary to perform encapsulation insulation on it.

[0027] In some embodiments, the encapsulation insulator of the current winding assembly is prone to insulation failure caused by cracking and surface creepage failure caused by water absorption under extreme and special environments (such as high temperature, low temperature, impact, outdoor use environment).

[0028] To address the above problems, some embodiments of the present application provide an improved winding assembly, which improves the anti-cracking and weather resistance of the winding assembly under extreme and special environments through the specific encapsulation structure of the encapsulation insulator in the winding assembly.

[0029] The exemplary embodiments of the present disclosure will be described in detail below with reference to the accompanying drawings.

[0030] Refer to Figure 1 and further refer to Figure 2 . Figure 1 Schematically shows a structural diagram of a winding assembly 100 according to an embodiment of the present application. Figure 2 Schematically shows Figure 1 a cross-sectional view of the winding assembly 100.

[0031] Refer to Figure 1 and Figure 2, the winding assembly 100 includes a support cylinder 110, a coil 170, and an encapsulating insulator 180. The support cylinder 110 includes a cylinder body 120, a first flange 150, and a second flange 160. The cylinder body 120 extends along a first direction X, and the cylinder body 120 has an outer wall 130 and an inner wall 140. The first flange 150 and the second flange 160 are respectively disposed at a first end and a second end of the cylinder body 120 along the first direction X opposite to each other. The coil 170 is wound around the outer wall 130 of the cylinder body 120 along the first direction X. The encapsulating insulator 180 encapsulates the support cylinder 110 and the coil 170, so that the space between the coil 170 and the outer wall 130 of the cylinder body 120, between the coils 170, between the coil 170 and the first flange 150, between the coil 170 and the second flange 160, the outer surface 190 of the first flange 150, and the inner wall 140 of the cylinder body 120 are all filled with the encapsulating insulator 180.

[0032] As shown in the figure, the first direction X in the figure is the length direction of the winding assembly 100.

[0033] According to some embodiments of the present application, the coil 170 includes at least one of a disk winding or a drop winding coil.

[0034] As Figure 2 shown, the coil 170 using a drop winding coil is wound around the outer wall 130 of the cylinder body 120 of the support cylinder 110. Although the coil 170 described in Figure 2 uses a drop winding coil, the present disclosure is not limited thereto. In some embodiments, the coil 170 may also be in the form of a disk winding.

[0035] In Figure 2 the illustrated example, in addition to filling the space between the coil 170 and the outer wall 130 of the cylinder body 120, between the coils 170, between the coil 170 and the first flange 150, and between the coil 170 and the second flange 160, the encapsulating insulator 180 is also filled on the outer surface 190 of the first flange 150 and the inner wall 140 of the cylinder body 120. In other words, except for the outer surface of the second flange 160, the entire winding assembly 100 (including the upper end surface of the winding assembly 100 and the inner wall of the support cylinder) is filled and wrapped with the encapsulating insulator 180.

[0036] Through the specific encapsulation structure of the encapsulating insulator, almost the entire winding assembly 100 is filled and wrapped with the encapsulating insulator 180, reducing the possibility of insulation failure caused by cracking and water absorption that are likely to occur in some parts of the winding assembly under extreme and special environments (such as high temperature, low temperature, impact, outdoor use environment), and improving the crack resistance and weather resistance of the winding assembly.

[0037] According to some embodiments of the present application, the encapsulating insulator 180 may be composed of an elastomeric insulating material. In some embodiments, the elastomeric insulating material may include silicone rubber (SiR).

[0038] As an epoxy resin casting, which is widely used as an insulation method for winding components in dry-type transformers, a relatively long gel / curing time (such as 4 - 8 hours) and post-curing time (such as 10 hours) are required in the production line to achieve the better performance of the epoxy material. In addition, some characteristics of the epoxy material will limit the performance of dry-type transformer applications (for example, the extreme environmental tolerance will be limited by the low-temperature crack resistance of the epoxy material). From the perspective of material substitution, silicone rubber can solve or partially solve the limitations faced by the epoxy material, thereby improving the robustness of dry-type transformers in extreme and special environments and expanding their application scope.

[0039] By setting the encapsulating insulator 180 as silicone rubber, a shorter curing time (such as 1 - 2 hours) can be achieved, higher product robustness for harsh environments (such as high temperature, low temperature, shock, low noise requirements, outdoor use), non-flammability, and low hygroscopicity when coating the coil can be obtained.

[0040] According to some embodiments of the present application, the support cylinder 110 is made of a rigid insulating material, that is, the cylinder body 120, the first flange 150, and the second flange 160 are all made of a rigid insulating material. In some embodiments, the rigid insulating material may include an epoxy fiberglass material.

[0041] In some embodiments, a primer is coated on the surface of the cylinder body 120. The primer can be used to strengthen the bonding interface between the support cylinder 110 and the encapsulating insulator 180, such as silicone rubber.

[0042] Further referring to Figure 3 and Figure 4 . Figure 3 Schematically shows a structural schematic diagram of the support cylinder 110 according to an embodiment of the present application. Figure 4 Schematically shows a structural schematic diagram of the first flange 150 according to an embodiment of the present application. As Figure 3 shown, before the encapsulating insulator 180 is cast, the first flange 150 and the second flange 160 are detachably sleeved on both ends of the cylinder body 120, and the upper and lower flanges are respectively designed to be assembled. As Figure 4As shown, the first flange 150 includes a first connection portion 200 and a first edge portion 210. The first connection portion 200 is used for plugging and connecting with the cylinder 120, so that the cylinder 120 is sleeved outside the first connection portion 200. The first edge portion 210 is connected to the first connection portion 200, and the first edge portion 210 extends beyond the outer wall 130 of the cylinder 120 when the first connection portion 200 is plugged and connected with the cylinder 120.

[0043] In Figure 4 the illustrated example, the first flange 150 is designed to have a bent shape, and its first edge portion 210 extends beyond the outer wall 130 of the cylinder 120 when the first connection portion 200 is plugged and connected with the cylinder 120 (as Figure 3 shown), so that the overall support cylinder 110 can provide support in the axial and radial directions.

[0044] Please continue to refer to Figure 3 and Figure 4 . According to some embodiments of the present application, at least one notch 220 extending along the circumferential direction of the first flange 150 is provided on the first flange 150. In Figure 4 the illustrated example, eight notches 220 are provided on the first flange 150. Although Figure 4 eight notches 220 are shown, it can be understood that the number of notches 220 can also be other numbers, such as five, seven, nine, etc., and the present disclosure does not limit this. In some embodiments, at least one notch 220 is equidistantly arranged on the circumference of the first flange 150. However, it can be understood that in other embodiments, at least one notch 220 can also be non-equidistantly arranged on the circumference of the first flange 150.

[0045] According to some embodiments of the present application, the notch 220 can extend through the first connection portion 200, and the notch 220 partially extends on the first edge portion 210.

[0046] As Figure 4 shown, the notch 220 extends through the first connection portion 200, so that the first connection portion 200 is separated into several sections by a plurality of notches 220, but the notch 220 does not extend through the first edge portion 210, but only partially extends on the first edge portion 210.

[0047] In such a design of the extension direction of the notch, it is easier for the encapsulating insulator 180 to pass through the notch 220 to reach the inner wall 140 of the cylinder 120 and the outer surface 190 of the first flange 150 during pouring.

[0048] Further refer to Figure 5 . Figure 5Schematically shown is a structural schematic diagram of a second flange 160 according to an embodiment of the present application. The second flange 160 includes a second connecting portion 230 and a second edge portion 240. The second connecting portion 230 is used for plug-in connection with the cylindrical body 120 to sleeved the cylindrical body 120 outside the second connecting portion 230. The second edge portion 240 is connected to the second connecting portion 230, and the second edge portion 240 extends beyond the outer wall 130 of the cylindrical body 120 when the second connecting portion 230 is plugged into the cylindrical body 120.

[0049] In Figure 5 the illustrated example, the second flange 160 is designed to have a bent shape, and its second edge portion 240 extends beyond the outer wall 130 of the cylindrical body 120 when the second connecting portion 230 is plugged into the cylindrical body 120 (as Figure 3 shown), so that the entire support cylinder 110 can provide support in the axial and radial directions.

[0050] According to some embodiments of the present application, at least one opening (not shown in the figure) is provided on the wall portion of the cylindrical body 120 for communicating the outer wall 130 and the inner wall 140. In some embodiments, the at least one opening may include a circular hole, a slot hole, etc., and the present disclosure does not limit the shape and number of the openings. In such a design, when casting, the encapsulating insulator 180 can more easily pass through the at least one opening to reach the inner wall 140 of the cylindrical body 120, so that the winding assembly 100 has better overall casting performance.

[0051] According to some embodiments of the present application, the present application provides a dry-type transformer including the winding assembly 100 described in the above embodiments.

[0052] The specific structure and function of the winding assembly 100 have been specifically described above. For the sake of brevity, they will not be elaborated here.

[0053] Further referring to Figure 6 . Figure 6 Schematically shown is a structural schematic diagram of a test fixture 600 for simulating the application of a fixing force according to an embodiment of the present application.

[0054] As Figure 6 shown, the test fixture 600 for simulating the application of a fixing force includes four pressing arms 610, and the four pressing arms 610 respectively press the winding assembly 100 along the length of the winding assembly 100. The points where the four pressing arms 610 respectively contact the upper end surface of the winding assembly 100 are respectively marked as points A, B, C, and D. The sections of the winding assembly 100 between points A, B, C, and D are respectively marked as A-B, B-C, C-D, and D-A.

[0055] Comparative Example 1: The winding assembly does not have a support cylinder, and the encapsulating insulator made of silicone rubber is directly encapsulated on the coil. The results obtained by simulating the application of a fixed force test are shown in Table 1.

[0056] Table 1

[0057]

[0058] Example 1: The winding assembly 100 has a support cylinder 110 (with a wall thickness of 1.5 mm), and the encapsulating insulator 180 made of silicone rubber encapsulates the support cylinder 110 and the coil 170. The results obtained by simulating the application of a fixed force test are shown in Table 2.

[0059] Table 2

[0060]

[0061]

[0062] According to Table 1 and Table 2, the support cylinder 110 improves the overall mechanical support performance of the winding assembly 100: after simulating the application of a fixed force, the vertical deformation at the compressed position decreases from 1.9% to 0.4%, and the vertical deformation at the uncompressed position decreases from 0.8% to 0.1%. Because in the case where the encapsulating insulator 180 is made of silicone rubber, due to the lower mechanical properties of silicone rubber casting compared to epoxy resin casting, an internal support structure, that is, the support cylinder 110, is required for overall reinforcement. The use of the support cylinder 110 can reduce the risks associated with the low-modulus silicone rubber material used for mechanical support.

[0063] Refer to Figure 7 , Figure 7 FIG. schematically shows a flowchart of a method 700 for manufacturing a winding assembly according to an embodiment of the present application.

[0064] The method 700 includes steps S710 to S760.

[0065] Step S710: Install the cylinder body 120 of the support cylinder 110 on the second flange 160 of the support cylinder 110;

[0066] Step S720: Sleeve the installed cylinder body 120 and the second flange 160 on the inner mold;

[0067] Step S730: Wind the coil 170 around the outer wall 130 of the cylinder body 120;

[0068] Step S740: Install the first flange 150 of the support cylinder 110 on the cylinder body 120;

[0069] Step S750: Place the support cylinder 110 wound with the coil 170 into the outer mold and pour it with a liquid encapsulating insulating material to form an encapsulating insulator 180. Among them, the encapsulating insulator 180 encapsulates the support cylinder 110 and the coil 170, so that the space between the coil 170 and the outer wall 130 of the cylinder body 120, between the coils 170, between the coil 170 and the first flange 150, between the coil 170 and the second flange 160, the outer surface 190 of the first flange 150, and the inner wall 140 of the cylinder body 120 are all filled with the encapsulating insulator 180; and

[0070] Step S760: Take out the cast and cured winding assembly 100 from the outer mold and remove the inner mold.

[0071] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present application, rather than to limit them; although the present application has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that they can still modify the technical solutions described in the foregoing embodiments, or perform equivalent replacements on some or all of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the scope of the technical solutions of the embodiments of the present application, and they should all be covered by the scope of the claims and the specification of the present application. In particular, as long as there is no structural conflict, the technical features mentioned in each embodiment can be combined in any way. The present application is not limited to the specific embodiments disclosed in the text, but includes all technical solutions falling within the scope of the claims.

Claims

1. A winding assembly (100), characterized in that, Comprising: A support cylinder (110), comprising: A cylinder body (120) extending along a first direction (X), the cylinder body (120) having an outer wall (130) and an inner wall (140); and A first flange (150) and a second flange (160), the first flange (150) and the second flange (160) being respectively disposed at a first end and a second end of the cylinder body (120) opposite to each other along the first direction (X); A coil (170), the coil (170) being wound around the outer wall (130) of the cylinder body (120) along the first direction (X); And An encapsulating insulator (180), the encapsulating insulator (180) encapsulating the support cylinder (110) and the coil (170), such that between the coil (170) and the outer wall (130) of the cylinder body (120), between the coils (170), between the coil (170) and the first flange (150), between the coil (170) and the second flange (160), the outer surface (190) of the first flange (150), and the inner wall (140) of the cylinder body (120) are all filled with the encapsulating insulator (180).

2. The winding assembly (100) according to claim 1, characterized in that, The first flange (150) comprises: A first connecting portion (200) for plug-in connection with the cylinder body (120) to sleeved the cylinder body (120) outside the first connecting portion (200); and A first edge portion (210) connected to the first connecting portion (200), the first edge portion (210) extending beyond the outer wall (130) of the cylinder body (120) when the first connecting portion (200) is plug-in connected to the cylinder body (120).

3. The winding assembly (100) according to claim 2, characterized in that, At least one notch (220) extending along the circumferential direction of the first flange (150) is provided on the first flange (150).

4. The winding assembly (100) according to claim 3, characterized in that, The notch (220) extends through the first connecting portion (200), and the notch (220) partially extends on the first edge portion (210).

5. The winding assembly (100) according to claim 1, wherein, The second flange (160) comprises: A second connecting portion (230) for plug-in connection with the cylinder body (120) to sleeved the cylinder body (120) outside the second connecting portion (230); and A second edge portion (240) connected to the second connecting portion (230), the second edge portion (240) extending beyond the outer wall (130) of the cylinder body (120) when the second connecting portion (230) is plug-in connected to the cylinder body (120).

6. The winding assembly (100) according to any one of claims 1-5, characterized in that, The encapsulating insulator (180) is composed of an elastomeric insulating material.

7. The winding assembly (100) according to claim 6, wherein, The elastomeric insulating material includes silicone rubber.

8. The winding assembly (100) according to any one of claims 1-5, characterized in that, The cylinder body (120), the first flange (150), and the second flange (160) are made of a rigid insulating material.

9. The winding assembly (100) according to claim 8, characterized in that, The rigid insulating material includes an epoxy fiberglass material.

10. The winding assembly (100) according to any one of claims 1-5, characterized in that, The coil (170) includes at least one of a pancake winding or a pendant winding coil.

11. The winding assembly (100) according to any one of claims 1-5, characterized in that, A surface enhancer is coated on the surface of the cylinder body (120).

12. The winding assembly (100) according to any one of claims 1-5, characterized in that, At least one opening is provided on the wall of the cylinder body (120) for communicating the outer wall (130) and the inner wall (140).

13. A dry-type transformer, characterized in that, Comprising the winding assembly (100) according to any one of claims 1-12.

14. A method for manufacturing a winding assembly (100) according to any one of claims 1 - 12, characterized in that, Comprising:[[]] Mount the cylinder body (120) of the support cylinder (110) on the second flange (160) of the support cylinder (110); Sheath the mounted cylinder body (120) and the second flange (160) on the inner mold; Wind the coil (170) around the outer wall (130) of the cylinder body (120); Mount the first flange (150) of the support cylinder (110) on the cylinder body (120); Place the support cylinder (110) wound with the coil (170) into the outer mold and pour it with a liquid encapsulating insulating material to form an encapsulating insulator (180), wherein the encapsulating insulator (180) encapsulates the support cylinder (110) and the coil (170), such that between the coil (170) and the outer wall (130) of the cylinder body (120), between the coils (170), between the coil (170) and the first flange (150), between the coil (170) and the second flange (160), the outer surface (190) of the first flange (150), and the inner wall (140) of the cylinder body (120) are all filled with the encapsulating insulator (180); and Take out the cast and cured winding assembly (100) from the outer mold and remove the inner mold.

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