Winding structure, winding method and epoxy resin vacuum casting electronic current transformer

Abstract

The application discloses a winding structure, a winding method and an epoxy resin vacuum casting electronic current transformer. The structure comprises a core and a primary winding. The primary winding is composed of first, second and third copper coil layers and is spirally arranged on the outer periphery of the core. The first copper coil layer is covered with a first insulating paper layer between the first copper coil layer and the second copper coil layer, and the second copper coil layer is covered with a second insulating paper layer between the second copper coil layer and the third copper coil layer. The number of turns of the second copper coil layer is less than that of the first copper coil layer, and a mounting space is reserved on the outer surface of the first copper coil layer. Limiting separators are arranged in the mounting space and are detachably connected to one end of the second copper coil layer, a plurality of groups of the limiting separators are distributed on the outer surface of the first copper coil layer in a circumferential direction, and first penetration gaps are formed between the limiting separators and the outer surface of the first copper coil layer. The third copper coil layer is distributed in a staggered manner with the second copper coil layer, and the sum of the number of turns of the third copper coil layer and the second copper coil layer is less than the number of turns of the first copper coil layer. Compared with the prior art, the application can improve the insulation performance and mechanical stability of the primary winding.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of mutual inductors, and in particular to a winding structure, a winding method and an epoxy resin vacuum casting electronic current transformer. BACKGROUND

[0002] Mutual inductors have become indispensable devices in the manufacture of power distribution system, facility and other power distribution switch control equipment. In the existing mutual inductor technology, in order to meet the requirements of high insulation performance and good partial discharge control, epoxy resin is generally used as the insulation material, and a fully enclosed structure is used to protect the internal core and winding. In order to achieve the design goals of high voltage, low excitation current and low loss, the winding structure in the prior art often uses multiple layers of copper wires to form a primary winding, sets an insulation paper layer between each layer, and covers a semiconductor corrugated paper shielding layer outside the winding to improve the electric field distribution and partial discharge characteristics.

[0003] Through research, the inventor found that since the multiple layers of copper wires are sequentially sleeved, the gap between the copper wires of adjacent layers is too narrow, which causes the subsequent insulation resin to be unable to completely penetrate between the multiple layers of copper wires. After the copper wires of adjacent layers lack the penetration of the insulation resin, the insulation paper layer of the mutual inductor will bear a larger voltage, and the interlayer electric field concentration phenomenon increases, ultimately resulting in a decrease in the insulation effect and operating stability of the mutual inductor. SUMMARY

[0004] The present application discloses a winding structure, a winding method and an epoxy resin vacuum casting electronic current transformer to solve the technical problems in the related art.

[0005] In order to solve the above problems, the present application adopts the following technical solutions:

[0006] In a first aspect, this application provides a winding structure applied to an epoxy resin vacuum-cast electronic current transformer, characterized in that the winding structure includes an iron core and further includes: a primary winding comprising a first copper coil layer and a second copper coil layer, wherein the first copper coil layer is spirally wound sequentially around the outer periphery of the iron core, and the second copper coil layer is spirally wound sequentially around the outer periphery of the first copper coil layer, a first insulating paper layer is provided between the first copper coil layer and the second copper coil layer, and the number of turns of the second copper coil layer is less than the number of turns of the first copper coil layer, so as to reserve an installation space on one side of the second copper coil layer and on the outer surface of the first copper coil layer; a limiting separator is disposed in the installation space and detachably connected to one end of the second copper coil layer, wherein multiple sets of the limiting separator are circumferentially spaced on the outer surface of the first copper coil layer, and a first penetration gap is formed between the limiting separator and the outer surface of the first copper coil layer; wherein the primary winding further includes a third copper coil layer, wherein the third copper coil layer is spirally wound sequentially on the outer surface of the multiple sets of limiting separators, and the third copper coil layer... A second insulating paper layer is also provided between the limiting separator and the limiting separator, and the second insulating paper layer circumferentially covers the limiting separator and the second copper ring layer; the third copper ring layer and the second copper ring layer are staggered on the outer periphery of the first copper ring layer, and the sum of the number of turns of the third copper ring layer and the number of turns of the second copper ring layer is less than the number of turns of the first copper ring layer; a first pouring hole is opened on the surface of the second insulating paper layer and at the position between the third copper ring layer and the second copper ring layer, so as to pour resin into the first penetration gap through the first pouring hole; the limiting separator is made of insulating material, and the limiting separator includes an overlapping part, a connecting part and a supporting part; wherein, the overlapping part is provided at the installation space, and the extension direction of the overlapping part is consistent with the extension direction of the outer periphery outline of the first copper ring layer; the connecting part is provided at one end of the overlapping part for detachable connection with one end of the outer ring segment of the second copper ring layer; multiple sets of supporting parts are provided at intervals on the overlapping part, and the supporting parts are used to abut against the first insulating paper layer on the surface of the first copper ring layer.

[0007] Secondly, this application provides a method for manufacturing a winding structure, used to produce the winding structure described above, comprising the following steps:

[0008] First, the first copper ring layer is spirally wound around the outer circumference of the iron core so that the outer circumference of the iron core is completely covered by the first copper ring layer. After the winding is completed, the first insulating paper layer is attached.

[0009] Select an initial point arbitrarily on the surface of the first insulating paper layer to wind the second copper ring layer. When winding to the last copper ring segment of the second copper ring layer, first pre-attach the connecting part to the last copper ring segment of the second copper ring layer, and then attach the last copper ring segment of the second copper ring layer together with the connecting part to the surface of the first insulating paper layer.

[0010] The position of the lap joint and the supporting part is adjusted to make the supporting part stably adhere to the surface of the first insulating paper layer;

[0011] The third copper ring layer is wound around the surface of the lap joint until the third copper ring layer is wound completely;

[0012] The third insulating paper layer is covered on the outer surface of the third copper ring layer;

[0013] The resin is poured into the second permeation gap through the second pouring hole, and the resin flows from the second permeation gap into the first permeation gap through the first pouring hole until the second permeation gap and the first permeation gap are filled with resin.

[0014] In a third aspect, the application provides an epoxy resin vacuum-poured electronic current transformer, comprising an insulating shell, a base, a secondary winding and the winding structure according to any one of the preceding aspects, wherein the winding structure is arranged in the insulating shell, the secondary winding is sleeved on the primary winding in the winding structure, and the base is installed at the bottom of the insulating shell.

[0015] The technical scheme adopted by the application can achieve the following beneficial effects:

[0016] 1. The first copper ring layer serves as a reference layer to provide a stable winding base. The second copper ring layer around the outer periphery has fewer turns and leaves installation space on one side. By arranging a limiting partition in the space, a plurality of first permeation gaps are formed between the outer surface of the first copper ring layer and the limiting partition, providing necessary storage space for uniform resin immersion. The third copper ring layer is spirally wound on the outer surface of the limiting partition and is distributed in a staggered manner with the second copper ring layer around the outer periphery of the first copper ring layer. This design allows the second insulating paper layer between the second and third copper ring layers to not be in the position of bearing the maximum voltage, which is beneficial to reducing the local electric field concentration phenomenon caused by uneven resin impregnation. In addition, the second insulating paper layer covers the limiting partition and the second copper ring layer, forming a continuous insulating medium. When epoxy resin is poured into the first permeation gap through the first pouring hole, the resin can fully infiltrate the entire gap along the preset channel, allowing the copper ring layers to be mechanically fixed and having good overall performance in terms of heat conduction and stress dispersion. This helps to alleviate the local discharge or high field effect that may be caused by the narrow gap between the insulating paper layers. At the same time, the sum of the turns of the third and second copper ring layers is controlled to be less than the turns of the first copper ring layer, making the voltage distribution of the winding structure more uniform, dispersing and reducing the voltage difference accumulated between the layers, improving the insulation effect and enhancing the overall operation stability;

[0017] 2. The design of the connecting part, to a certain extent, improves the contact state between the outer copper ring segment of the second copper ring layer and the adjacent copper ring segment, avoiding friction or interference between the connecting part and the contact area of ​​another adjacent copper ring layer when the outer ring segment of the second copper ring layer is fitted with the connecting part, thereby reducing local stress concentration and minimizing impact on the thermal conductivity of the second copper ring layer itself. Furthermore, this arc-shaped groove structure utilizes the elastic characteristics of the first and second elastic sub-parts to adapt to certain dimensional deviations and mechanical vibrations during assembly, providing positioning support for the arc-shaped groove at one end of the outer ring segment of the second copper ring layer, thus allowing the connecting part to stably engage with the outer ring segment at one end of the second copper ring layer. It should be noted that the "first elastic sub-part" and "second elastic sub-part" here refer to components with a certain elastic deformation capacity, whose design can alleviate the fastening stress caused by external factors during assembly to a certain extent. The "arc-shaped groove" is a groove-shaped structure formed by the smooth transition of the two elastic sub-parts, and its size and shape design contribute to a fitting and engaging state with the shape of the outer ring segment at one end of the second copper ring layer.

[0018] 3. The support portion serves to fix and guide the first support sub-part and the overlapping part, while the second support sub-part and the long abutting surface it forms provide a continuous and stable support area after contacting the first insulating paper layer. In fact, the second support sub-part abuts against the first copper ring layer, except that there is a layer of first insulating paper in between. This not only helps to evenly distribute local stress, but also forms a relatively stable overall structure during the resin curing process, thereby reducing the risk of deformation of the insulating paper layer and uneven local electric field caused by local stress concentration to a certain extent. Attached Figure Description

[0019] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0020] Figure 1 This is a schematic diagram of the winding structure after the copper ring of the hidden primary winding is shown in an embodiment of this application;

[0021] Figure 2 This is a partial schematic diagram illustrating the connection relationship between the primary winding and the iron core according to an embodiment of this application;

[0022] Figure 3 yes Figure 2 Enlarged view of part A in the image;

[0023] Figure 4This is a schematic diagram illustrating the structure of an epoxy resin vacuum-cast electronic current transformer according to an embodiment of this application.

[0024] In the picture:

[0025] 1. Iron core; 2. Primary winding; 21. First copper ring layer; 22. Second copper ring layer; 23. Third copper ring layer; 3. First insulating paper layer; 4. Limiting separator; 41. Overlapping part; 411. Overlapping surface; 4111. Arc-shaped fitting sub-surface; 412. Penetrating surface; 42. Connecting part; 421. First elastic sub-part; 422. Second elastic sub-part; 423. Arc-shaped groove; 424. Reinforcing sub-part; 43. Support part; 431. First support sub-part; 432. Second support sub-part; 4321. Abutting surface; 5. First penetrating gap; 6. Second insulating paper layer; 61. First casting hole; 7. Third insulating paper layer; 71. Second casting hole; 8. Second penetrating gap; 9. Insulating shell; 10. Base; 11. Secondary winding. Detailed Implementation

[0026] To make the objectives, technical solutions, and advantages of this invention clearer, the technical solutions of this invention will be described in detail below. Obviously, the described embodiments are merely some embodiments of this invention, and not all embodiments. Based on the embodiments of this invention, all other implementation methods obtained by those skilled in the art without creative effort are within the scope of protection of this invention.

[0027] The terms "first," "second," etc., used in the specification and claims of this application are used to distinguish similar objects and not to describe a specific order or sequence. It should be understood that such use of data can be interchanged where appropriate so that embodiments of this application can be implemented in orders other than those illustrated or described herein, and the objects distinguished by "first," "second," etc., are generally of the same class and the number of objects is not limited; for example, a first object can be one or more. Furthermore, in the specification and claims, "and / or" indicates at least one of the connected objects, and the character " / " generally indicates that the preceding and following objects are in an "or" relationship.

[0028] The following is in conjunction with the appendix Figures 1 to 4 This application provides a detailed description of a winding structure, winding method, and epoxy resin vacuum casting electronic current transformer through specific embodiments and application scenarios.

[0029] Firstly, combining Figures 1 to 3This application discloses a winding structure for use in an epoxy resin vacuum-cast electronic current transformer. The winding structure includes an iron core 1, a primary winding 2, and a limiting separator 4. The primary winding 2 includes a first copper ring layer 21 and a second copper ring layer 22. The first copper ring layer 21 is spirally wound around the outer periphery of the iron core 1, and the second copper ring layer 22 is spirally wound around the outer periphery of the first copper ring layer 21. A first insulating paper layer 3 is provided between the first copper ring layer 21 and the second copper ring layer 22. The number of turns of the second copper ring layer 22 is less than the number of turns of the first copper ring layer 21, so as to reserve installation space on one side of the second copper ring layer 22 and on the outer surface of the first copper ring layer 21.

[0030] For example, the limiting separator 4 is arranged in the installation space and is detachably connected to one end of the second copper ring layer 22. Multiple sets of limiting separator 4 are distributed circumferentially on the outer surface of the first copper ring layer 21, and a first permeation gap 5 is formed between the limiting separator 4 and the outer surface of the first copper ring layer 21.

[0031] For example, the primary winding 2 also includes a third copper ring layer 23, which is spirally wound around the outer surface of multiple sets of limiting separators 4. A second insulating paper layer 6 is also provided between the third copper ring layer 23 and the limiting separators 4, and the second insulating paper layer 6 circumferentially covers both the limiting separators 4 and the second copper ring layer 22. Furthermore, the cross-sectional shape of a single copper ring segment of the first copper ring layer 21, the second copper ring layer 22, and the third copper ring layer 23 is circular.

[0032] For example, the third copper ring layer 23 and the second copper ring layer 22 are staggered around the outer periphery of the first copper ring layer 21, and the sum of the number of turns of the third copper ring layer 23 and the number of turns of the second copper ring layer 22 is less than the number of turns of the first copper ring layer 21; furthermore, a first pouring hole 61 is provided on the surface of the second insulating paper layer 6 at a position between the third copper ring layer 23 and the second copper ring layer 22, so that resin can be poured into the first permeation gap 5 through the first pouring hole 61.

[0033] Based on this, the first copper ring layer 21 serves as a reference layer, providing a large winding base. The second copper ring layer 22, which is arranged sequentially on its outer periphery, has a reserved installation space on one side due to its smaller number of turns. The installation space forms multiple first penetration gaps 5 with the outer surface of the first copper ring layer 21 through the limiting separator 4, thereby providing the necessary storage cavity for the uniform impregnation of the subsequent resin.

[0034] Meanwhile, the third copper ring layer 23 is spirally wound around the outer surface of each set of limiting separators 4, and is staggered with the second copper ring layer 22 on the outer periphery of the first copper ring layer 21. This ensures that the second insulating paper layer 6 between the second copper ring layer 22 and the third copper ring layer 23 is not simultaneously in the position of bearing the maximum voltage, which to a certain extent helps to reduce the local electric field concentration caused by uneven impregnation of insulating resin between the layers.

[0035] Furthermore, the second insulating paper layer 6 forms a continuous insulating medium when covering the limiting separator 4 and the second copper ring layer 22. When the first pouring hole 61 is used to inject epoxy resin into the first penetration gap 5, the resin can fully wet the entire first penetration gap 5 along the preset channel, so that the first copper ring layer 21, the second copper ring layer 22 and the third copper ring layer 23 are not only mechanically fixed, but also have good integrity in terms of heat conduction and stress dispersion. This design is beneficial to alleviate the partial discharge or local high field effect that may occur due to the narrow gap between the insulating paper layers to a certain extent.

[0036] Furthermore, by controlling the sum of the number of turns of the third copper ring layer 23 and the second copper ring layer 22 to be lower than the number of turns of the first copper ring layer 21, the entire winding structure exhibits a more uniform voltage distribution, which helps to disperse and reduce the voltage difference accumulated between layers, improve the insulation effect, and enhance the overall operational stability. At the same time, since the second copper ring layer 22 is staggered on the outer periphery of the third copper ring layer 23, and the sum of the number of turns of the third copper ring layer 23 and the second copper ring layer 22 is less than the number of turns of the first copper ring layer 21, a gap is reserved between the second copper ring layer 22 and the third copper ring layer 23. The first pouring hole 61 is opened here, so epoxy resin can be smoothly poured into the first penetration gap 5 through the first pouring hole 61.

[0037] It is worth noting that, although there is some ambiguity in the terminology regarding the setting of the limiting separator 4 and the first penetration gap 5, the limiting separator 4 referred to in this embodiment refers to a component that can be detached and connected to the second copper ring layer 22 when necessary, while forming a gap sufficient for resin to penetrate. The first penetration gap 5 refers to the gap reserved between the limiting separator 4 and the outer surface of the first copper ring layer 21, which allows the resin to be fully impregnated. Its design is beneficial to reduce local stress concentration and voltage unevenness to a certain extent, thereby improving the insulation performance and long-term stability of the transformer during actual operation.

[0038] Overall, through the combined effect of the above-mentioned structural elements, the present invention, to a certain extent, helps to alleviate the problems of local electric field concentration and increased pressure on the insulating paper layer caused by insufficient resin impregnation in multi-layer copper coil windings, while optimizing the electrical and mechanical properties of the windings, thereby improving the overall operating efficiency of the entire instrument transformer.

[0039] In some implementations, combined with Figures 1 to 3 The limiting separator 4 is made of insulating material and includes an overlapping part 41, a connecting part 42 and a supporting part 43; furthermore, the insulating material can be made of glass fiber, mica tape or DMD insulating material.

[0040] For example, the overlapping portion 41 is provided in the installation space, and the extension direction of the overlapping portion 41 is consistent with the extension direction of the outer periphery outline of the first copper ring layer 21; the connecting portion 42 is provided at one end of the overlapping portion 41 for detachable connection with one end of the outer ring segment of the second copper ring layer 22; the supporting portion 43 is provided in multiple sets at intervals on the overlapping portion 41, and the supporting portion 43 is used to abut against the first insulating paper layer 3 on the surface of the first copper ring layer 21.

[0041] Based on this, the overlapping part 41 is set in the installation space, and its extension direction is consistent with the outer periphery outline of the first copper ring layer 21. This design helps to form a relatively continuous and stable mounting surface, so that the third copper ring layer 23 can be smoothly overlapped on the overlapping part 41. At the same time, the connecting part 42 is set at one end of the overlapping part 41 to achieve a detachable connection with one end of the outer ring section of the second copper ring layer 22. This detachable design is beneficial to adjust or replace the relationship between the limiting separator 4 and the copper ring layer during subsequent assembly or maintenance, thereby having a positive impact on the overall performance of the winding structure. In addition, the support part 43 is provided in multiple sets at intervals on the overlapping part 41. Its function is to abut against the first insulating paper layer 3 on the surface of the first copper ring layer 21, provide local mechanical support and maintain the uniform distribution of the insulating paper layer of the first copper ring layer 21, so as to form a stable overall structure after the resin is cured, and reduce the structural deformation or uneven insulation that may be caused by local stress concentration.

[0042] It should be noted that "overlapping part 41" here mainly refers to the component that is positioned relative to the first copper ring layer 21 to assist in forming the impregnation gap, and at the same time provides a stable installation base for the winding of the third copper ring layer 23; "connecting part 42" refers to the component used to realize the detachable connection with the outer ring section of the second copper ring layer 22, and "supporting part 43" refers to the part used for local support and abutment against the first insulating paper layer 3 to maintain the stability of the overall structure. Through the synergistic effect of their respective structural features, each component is beneficial to optimizing the resin impregnation effect to a certain extent, reducing the risk of local voltage rise and partial discharge caused by insufficient resin impregnation of the insulating paper layer, thereby improving the overall insulation performance and operational stability of the transformer.

[0043] For example, the overlapping portion 41 has an overlapping surface 411 and a permeation surface 412 facing away from each other. The overlapping surface 411 is used for the third copper ring layer 23 to be surrounded. A portion of the first permeation gap 5 is formed between the permeation surface 412 and the outer surface of the first copper ring layer 21.

[0044] In some implementations, such as Figures 1 to 3 As shown, the connecting portion 42 includes a first elastic sub-portion 421 and a second elastic sub-portion 422. Both the first elastic sub-portion 421 and the second elastic sub-portion 422 extend in an arc shape away from the overlapping portion 41, and the surfaces of the first elastic sub-portion 421 and the second elastic sub-portion 422 facing away from the overlapping portion 41 are smoothly connected to form an arc-shaped groove 423 that engages with one end of the outer ring segment of the second copper ring layer 22. The length of the arc-shaped groove 423 is 3 / 4 of the circumference of the cross-section of one end of the outer ring segment of the second copper ring layer 22. When the arc-shaped groove 423 is engaged with one end of the outer ring segment of the second copper ring layer 22, the arc-shaped groove 423 avoids the contact area between the outer ring segment of the second copper ring layer 22 and another adjacent copper ring segment. For example, the first elastic sub-portion 421 and the second elastic sub-portion 422 can be made of some insulating rubber materials, such as silicone rubber, EPDM rubber, and polyurethane rubber.

[0045] This design, to a certain extent, improves the contact state between the outer copper ring segment of the second copper ring layer 22 and adjacent copper ring segments, preventing friction or interference between the connecting part 42 and the contact area of ​​another adjacent copper ring layer when the outer ring segment of the second copper ring layer 22 is fitted with the connecting part 42. This reduces local stress concentration and minimizes the impact on the thermal conductivity of the second copper ring layer 22 itself. Furthermore, the arc-shaped groove 423 structure utilizes the elastic characteristics of the first and second elastic sub-parts 422 to adapt to certain dimensional deviations and mechanical vibrations during assembly. This allows the outer ring segment at one end of the second copper ring layer 22 to provide positioning support for the arc-shaped groove 423, thereby enabling the connecting part 42 to be stably engaged with the outer ring segment at one end of the second copper ring layer 22. It should be noted that the “first elastic sub-part 421” and “second elastic sub-part 422” refer to components with a certain elastic deformation capability. Their design can alleviate the fastening stress caused by external factors during the assembly process to a certain extent. The “arc-shaped groove 423” is a groove-shaped structure formed by the smooth transition of the two elastic sub-parts. Its size and shape design are conducive to the matching and snapping state with the outer ring section of one end of the second copper ring layer 22.

[0046] For example, the connecting portion 42 further includes a reinforcing sub-portion 424, on which both the first elastic sub-portion 421 and the second elastic sub-portion 422 are disposed. The reinforcing sub-portion 424 is connected to one end of the overlapping portion 41. Furthermore, the minimum thickness of the reinforcing sub-portion 424 is greater than the thickness of the first elastic sub-portion 421, and the minimum thickness of the reinforcing sub-portion 424 is greater than the thickness of the second elastic sub-portion 422. With this configuration, since the shape of the reinforcing sub-portion 424 itself is irregular, different parts have different thicknesses. The minimum thickness of the reinforcing sub-portion 424 is also greater than the thicknesses of the second elastic sub-portion 422 and the first elastic sub-portion 421. This makes the reinforcing sub-portion 424 more stable than the second elastic sub-portion 422 and the first elastic sub-portion 421. After being subjected to external forces, the reinforcing sub-portion 424 also has better resistance to deformation, thereby avoiding, to a certain extent, the impact on the subsequent installation position of the overlapping portion 41 after the connecting portion 42 is snapped into place.

[0047] In some implementations, combined with Figures 1 to 3 The outer diameter of the cross-section of each copper ring segment in the first copper ring layer 21, the second copper ring layer 22, and the third copper ring layer 23 is the same. For example, the overlapping surface 411 has an arc-shaped fitting surface 4111 at the outer ring segment near the second copper ring layer 22. The curvature of the arc-shaped fitting surface 4111 matches the outer circumferential curvature of the cross-section of each copper ring segment in the third copper ring layer 23, and the arc-shaped fitting surface 4111 is the starting point for winding the third copper ring layer 23. For example, when the second insulating paper layer 6 is attached to the overlapping surface 411, the shape of the portion of the second insulating paper layer 6 corresponding to the arc-shaped fitting surface 4111 also matches the shape of the arc-shaped fitting surface 4111. Thus, the starting point for winding the third copper ring layer 23 is also the recessed portion of the second insulating paper layer 6 corresponding to the arc-shaped fitting surface 4111.

[0048] For example, along the outer periphery of the first copper ring layer 21, after the third copper ring layer 23 is spirally wound and formed starting from the arc-shaped mating surface 4111, the distance between the starting copper ring segment of the third copper ring layer 23 and one end of the outer ring segment of the second copper ring layer 22 is greater than the cross-sectional outer diameter of a single copper ring segment of the first copper ring layer 21.

[0049] Based on this, when manually winding the third copper ring layer 23, it is not necessary to deliberately measure the starting point of winding the third copper ring layer 23. Instead, the initial winding copper ring segment of the third copper ring layer 23 can be directly aligned with the arc-shaped fitting surface 4111 and placed in it. The arc-shaped fitting surface 4111 is used as the starting point for winding the third copper ring layer 23. After this setting, the formed third copper ring layer 23 will form a certain distance with the second copper ring layer 22, and this distance is greater than the cross-sectional outer diameter of a single copper ring segment of the first copper ring layer 21. At the same time, this part is also the weak point of the entire first winding. Therefore, the first pouring hole 61 can be set here to facilitate the injection of epoxy resin into the first penetration gap 5 through this point.

[0050] In some implementations, combined with Figures 1 to 3 The support portion 43 includes a first support sub-portion 431 and a second support sub-portion 432. The first support sub-portion 431 is connected to the overlapping portion 41, and the second support sub-portion 432 is located at the end of the first support sub-portion 431 away from the overlapping portion 41.

[0051] For example, the surface of the second support sub-part 432 facing away from the first support sub-part 431 is configured as an abutment surface 4321. The length of the abutment surface 4321 is greater than the sum of the cross-sectional outer diameters of individual copper ring segments of the two first copper ring layers 21. After the abutment surface 4321 abuts against the surface of the first insulating paper layer 3, at least two individual copper ring segments of the first copper ring layers 21 are located within the projection range of the abutment surface 4321.

[0052] This configuration helps to disperse and alleviate local mechanical stress in the primary winding 2, reducing local deformation and displacement caused by external vibration, temperature fluctuations, or mechanical impact. Specifically, the support portion 43, through the connection between the first support sub-portion 431 and the overlapping portion 41, serves to fix and guide the structure. The second support sub-portion 432 and the resulting longer contact surface 4321 provide a continuous and stable support area after contacting the first insulating paper layer 3 (actually, it contacts the first copper ring layer 21, but with a layer of first insulating paper layer 3 in between). This not only helps to evenly distribute local stress but also forms a relatively stable overall structure during resin curing, thereby reducing the risk of deformation of the insulating paper layer and uneven local electric field caused by local stress concentration.

[0053] It should be noted that the “contact surface 4321” here refers to the surface on the second support sub-part 432 that is used to contact the insulating paper layer and transmit mechanical support, while the “projection range” refers to the area covered by the contact surface 4321 in the vertical direction when it contacts the insulating paper layer. This design allows the pressure applied by the second support sub-part 432 to the surface of the first copper ring layer 21 to be dispersed in the contact area, which to a certain extent helps to improve the overall mechanical stability and electrical performance of the winding structure, and also helps to improve the heat conduction effect and reduce the possibility of local partial discharge.

[0054] In some implementations, combined with Figures 1 to 3 The outer surface of the third copper ring layer 23 is covered with a third insulating paper layer 7, and a second permeation gap 8 is formed between the third insulating paper layer 7 and the second copper ring layer 22 and on one side of the third copper ring layer 23.

[0055] For example, the third insulating paper layer 7 has a second pouring hole 71. When pouring resin, it enters the second permeation gap 8 through the second pouring hole 71, and then enters the first permeation gap 5 through the first pouring hole 61.

[0056] With this configuration, the third insulating paper layer 7 not only provides an additional physical barrier, but the second penetration gap 8 reserved between it and the second copper ring layer 22 also provides an auxiliary channel for resin pouring. This allows the resin to fill the gaps between the copper ring layers more fully during the curing process, improving heat conduction and dispersing stress. Here, the "second penetration gap 8" refers to the gap reserved between the third insulating paper layer 7 and the adjacent copper ring layer, while the "second pouring hole 71" is a dedicated orifice for allowing the resin to preferentially enter this gap. The synergistic effect of both helps the resin form a continuous and uniform insulating medium between the layers, thereby contributing to improving the safety and stability of the transformer during long-term operation.

[0057] Secondly, this application also provides a method for manufacturing a winding structure, used to produce the winding structure in the above embodiments, comprising the following steps:

[0058] First, the first copper ring layer 21 is spirally wound around the outer circumference of the iron core 1 so that the outer circumference of the iron core 1 is completely covered by the first copper ring layer 21. After the winding is completed, the first insulating paper layer 3 is attached.

[0059] The second copper ring layer 22 is wound around an arbitrary starting point on the surface of the first insulating paper layer 3. When the winding reaches the last copper ring segment of the second copper ring layer 22, the connecting part 42 is first pre-clamped onto the last copper ring segment of the second copper ring layer 22, and then the last copper ring segment of the second copper ring layer 22 together with the connecting part 42 is attached to the surface of the first insulating paper layer 3.

[0060] Adjust the positions of the overlapping part 41 and the support part 43 so that the support part 43 is stably attached to the surface of the first insulating paper layer 3 after avoiding the second copper ring layer 22;

[0061] A third copper ring layer 23 is wrapped around the surface of the overlapping part 41 until the third copper ring layer 23 is completely wrapped.

[0062] A third insulating paper layer 7 is applied to the outer surface of the third copper ring layer 23;

[0063] Resin is poured into the second permeation gap 8 through the second pouring hole 71. The resin flows from the second permeation gap 8 into the first permeation gap 5 through the first pouring hole 61 until both the second permeation gap 8 and the first permeation gap 5 are filled with resin, at which point the pouring stops.

[0064] It is worth noting that, in the appendix to this application Figure 3 The dashed lines with arrows indicate the flow direction of the epoxy resin pouring. One of the dashed lines with arrows flows into the second permeation gap 8, and the other dashed line with arrows flows into the first permeation gap 5.

[0065] Thirdly, this application also provides an epoxy resin vacuum-cast electronic current transformer, combined with... Figure 4 It includes an insulating shell 9, a base 10, a secondary winding 11, and the winding structure in any of the above embodiments, wherein,

[0066] The winding structure is located inside the insulating shell 9, the secondary winding 11 is sleeved on the primary winding 2 in the winding structure, and the base 10 is installed at the bottom of the insulating shell 9.

[0067] It should be noted that, in this document, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Unless otherwise specified, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes that element.

[0068] Furthermore, it should be noted that the scope of the methods and apparatus in the embodiments of this application is not limited to performing functions in the order shown or discussed, but may also include performing functions substantially simultaneously or in the reverse order, depending on the functions involved. For example, the described methods may be performed in a different order than described, and various steps may be added, omitted, or combined. In addition, features described with reference to certain examples may be combined in other examples.

[0069] The above description is merely a specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any changes or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in the present invention should be included within the scope of protection of the present invention.

Claims

1. A winding structure applied to an epoxy resin vacuum-cast electronic current transformer, characterized in that, The winding structure includes an iron core (1) and also includes: A primary winding (2) includes a first copper ring layer (21) and a second copper ring layer (22). The first copper ring layer (21) is spirally wound around the outer periphery of the iron core (1), and the second copper ring layer (22) is spirally wound around the outer periphery of the first copper ring layer (21). A first insulating paper layer (3) is provided between the first copper ring layer (21) and the second copper ring layer (22). The number of turns of the second copper ring layer (22) is less than the number of turns of the first copper ring layer (21) so as to reserve installation space on one side of the second copper ring layer (22) and on the outer surface of the first copper ring layer (21). A limiting separator (4) is disposed in the installation space and detachably connected to one end of the second copper ring layer (22). Multiple sets of the limiting separator (4) are circumferentially distributed on the outer surface of the first copper ring layer (21), and a first permeation gap (5) is formed between the limiting separator (4) and the outer surface of the first copper ring layer (21). The primary winding (2) also includes a third copper ring layer (23), which is spirally wound on the outer surface of multiple sets of limiting separators (4) in sequence, and a second insulating paper layer (6) is also provided between the third copper ring layer (23) and the limiting separators (4), and the second insulating paper layer (6) covers the limiting separators (4) and the second copper ring layer (22) circumferentially; The third copper ring layer (23) and the second copper ring layer (22) are misaligned around the outer periphery of the first copper ring layer (21), and the sum of the number of turns of the third copper ring layer (23) and the number of turns of the second copper ring layer (22) is less than the number of turns of the first copper ring layer (21). A first pouring hole (61) is provided on the surface of the second insulating paper layer (6) and at a position between the third copper ring layer (23) and the second copper ring layer (22) so that resin can be poured into the first permeation gap (5) through the first pouring hole (61); The limiting separator (4) is made of insulating material, and the limiting separator (4) includes an overlapping part (41), a connecting part (42), and a supporting part (43); wherein, The overlapping part (41) is provided in the installation space, and the extension direction of the overlapping part (41) is consistent with the extension direction of the outer periphery outline of the first copper ring layer (21). The connecting part (42) is located at one end of the overlapping part (41) and is used to detachably connect to one end of the outer ring section of the second copper ring layer (22); The support (43) is provided in multiple sets at intervals on the overlapping part (41), and the support (43) is used to abut against the first insulating paper layer (3) on the surface of the first copper ring layer (21).

2. The winding structure according to claim 1, characterized in that, The overlapping portion (41) has an overlapping surface (411) and a permeation surface (412) facing away from each other. The overlapping surface (411) is used for the third copper ring layer (23) to be surrounded. A portion of the first permeation gap (5) is formed between the permeation surface (412) and the outer surface of the first copper ring layer (21).

3. The winding structure according to claim 1, characterized in that, The connecting portion (42) includes a first elastic sub-portion (421) and a second elastic sub-portion (422), wherein, Both the first elastic sub-part (421) and the second elastic sub-part (422) extend in an arc shape away from the overlapping part (41), and the surfaces of the first elastic sub-part (421) and the second elastic sub-part (422) away from the overlapping part (41) are smoothly connected to form an arc-shaped groove (423) that fits into one end of the outer ring section of the second copper ring layer (22). The length of the arc-shaped slot (423) is 3 / 4 of the cross-sectional circumference of the outer ring section at one end of the second copper ring layer (22); When the arc-shaped groove (423) is in a sleeved state with one end of the outer ring segment of the second copper ring layer (22), the arc-shaped groove (423) avoids the contact area between the outer ring segment of the second copper ring layer (22) and the adjacent copper ring segment.

4. The winding structure according to claim 3, characterized in that, The connecting part (42) further includes a reinforcing sub-part (424), wherein the first elastic sub-part (421) and the second elastic sub-part (422) are both provided on the reinforcing sub-part (424), and the reinforcing sub-part (424) is connected to one end of the overlapping part (41); The minimum thickness of the reinforcing sub-part (424) is greater than the thickness of the first elastic sub-part (421), and the minimum thickness of the reinforcing sub-part (424) is greater than the thickness of the second elastic sub-part (422).

5. The winding structure according to claim 2, characterized in that, The cross-sectional outer diameter of a single copper ring segment in the first copper ring layer (21), the second copper ring layer (22), and the third copper ring layer (23) is the same; The overlapping surface (411) has an arc-shaped fitting surface (4111) at one end of the outer ring segment near the second copper ring layer (22). The curvature of the arc-shaped fitting surface (4111) matches the outer circumferential curvature of a single copper ring segment of the third copper ring layer (23), and the arc-shaped fitting surface (4111) is the starting point for winding the third copper ring layer (23). Along the outer periphery of the first copper ring layer (21), after the third copper ring layer (23) is spirally wound from the arc-shaped mating surface (4111) in sequence, the distance between the starting copper ring segment of the third copper ring layer (23) and one end of the outer ring segment of the second copper ring layer (22) is greater than the cross-sectional outer diameter of a single copper ring segment of the first copper ring layer (21).

6. The winding structure according to claim 1, characterized in that, The support portion (43) includes a first support sub-portion (431) and a second support sub-portion (432). The first support sub-portion (431) is connected to the overlapping portion (41), and the second support sub-portion (432) is located at the end of the first support sub-portion (431) away from the overlapping portion (41). The surface of the second support sub-part (432) facing away from the first support sub-part (431) is configured as an abutment surface (4321), the length of which is greater than the sum of the cross-sectional outer diameters of the individual copper ring segments of the two first copper ring layers (21), wherein, After the contact surface (4321) contacts the surface of the first insulating paper layer (3), at least two individual copper ring segments of the first copper ring layer (21) are located within the projection range of the contact surface (4321).

7. The winding structure according to any one of claims 1-6, characterized in that, The outer surface of the third copper ring layer (23) is covered with a third insulating paper layer (7), and a second permeation gap (8) is formed between the third insulating paper layer (7) and the second copper ring layer (22) and on one side of the third copper ring layer (23). The third insulating paper layer (7) has a second pouring hole (71). When pouring resin, it enters the second permeation gap (8) through the second pouring hole (71) and then enters the first permeation gap (5) through the first pouring hole (61).

8. A method for manufacturing a winding structure, used to produce the winding structure of claim 7, characterized in that, Includes the following steps: First, the first copper ring layer (21) is spirally wound around the outer periphery of the iron core (1) so that the outer periphery of the iron core (1) is completely covered by the first copper ring layer (21). After the winding is completed, the first insulating paper layer (3) is attached. When the first insulating paper layer (3) is arbitrarily selected as the initial point, the second copper ring layer (22) is wound. When the winding reaches the last copper ring segment of the second copper ring layer (22), the connecting part (42) is first pre-clamped onto the last copper ring segment of the second copper ring layer (22), and then the last copper ring segment of the second copper ring layer (22) together with the connecting part (42) is attached to the surface of the first insulating paper layer (3). Adjust the positions of the overlapping part (41) and the supporting part (43) so that the supporting part (43) can stably adhere to the surface of the first insulating paper layer (3) after avoiding the second copper ring layer (22); A third copper ring layer (23) is wrapped around the surface of the overlapping part (41) until the third copper ring layer (23) is completed; A third insulating paper layer (7) is applied to the outer surface of the third copper ring layer (23); Resin is poured into the second permeation gap (8) through the second pouring hole (71). The resin flows from the second permeation gap (8) into the first permeation gap (5) through the first pouring hole (61) until both the second permeation gap (8) and the first permeation gap (5) are filled with resin and then the pouring stops.

9. An epoxy resin vacuum-cast electronic current transformer, characterized in that, It includes an insulating shell (9), a base (10), a secondary winding (11), and a winding structure according to any one of claims 1-7, wherein, The winding structure is located inside the insulating shell (9), the secondary winding (11) is sleeved on the primary winding (2) in the winding structure, and the base (10) is installed at the bottom of the insulating shell (9).

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