Shielding structure for low-voltage side of transformer and transformer

Abstract

The utility model discloses a shielding structure for the low voltage side of transformer, including first shielding piece, second shielding piece and shielding tape, the first shielding piece covers on the inner surface of low voltage ascending flanged base, the second shielding piece covers on the inner surface of low voltage box cover, the shielding tape includes first bending portion and second bending portion, and the first bending portion and the second bending portion are in the same shape. The first bending part and the second bending part are in butt joint to form a bent shielding tape structure, the first bending part is attached to and detachably connected with the first shielding piece, and the second bending part is attached to and detachably connected with the second shielding piece, so that the shielding tape connects the first shielding piece and the second shielding piece into an integral shielding structure. The shielding structure is reasonable in layout, simple in structure, good in magnetic resistance effect, safe and reliable. The utility model further provides the transformer comprising the shielding structure for the low-voltage side of the transformer.

Description

Technical Field

[0001] This utility model specifically relates to a shielding structure for the low-voltage side of a transformer and a transformer. Background Technology

[0002] In recent years, with the continuous growth of energy demand, generator transformers, as core equipment of the power system, have been widely used in the power grid. In the field of transformer technology, there is a "6-degree rule," which states that for every 6°C increase in transformer temperature, its service life is reduced by half, reflecting the phenomenon that the operating temperature of a transformer directly determines its lifespan. The temperature rise of a transformer during operation is significantly affected by the low-voltage section. The low-voltage section (or low-voltage side) of a generator transformer generally experiences very high current. Higher current generates greater leakage flux, which in turn generates a larger induced current, making the low-voltage section more prone to overheating and experiencing a higher temperature rise.

[0003] Based on the above, non-magnetic steel plates are typically used for the low-voltage riser base and low-voltage tank cover. Additionally, depending on the specific current value, copper shielding is selectively arranged inside and outside the low-voltage riser base and low-voltage tank cover to prevent leakage magnetic flux from entering the low-voltage tank cover or low-voltage riser base. However, for high-current generator transformers with currents exceeding 20000A, these measures are often not very effective. Therefore, how to provide an effective copper shielding arrangement structure is a problem that designers of high-current generator transformers need to solve. Utility Model Content

[0004] The technical problem to be solved by this utility model is to address the aforementioned shortcomings in the prior art by providing a shielding structure for the low-voltage side of a transformer. This shielding structure has good magnetic shielding effect and is safe and reliable. This utility model also provides a transformer that includes the above-mentioned shielding structure for the low-voltage side of a transformer.

[0005] This utility model provides a shielding structure for the low-voltage side of a transformer, including a first shielding component, a second shielding component, and a shielding strip. The first shielding component covers the inner surface of the low-voltage riser, and the second shielding component covers the inner surface of the low-voltage tank cover. The shielding strip includes a first bend and a second bend, which are joined together to form a bend-shaped shielding strip structure. The first bend is attached to and detachably connected to the first shielding component, and the second bend is attached to and detachably connected to the second shielding component, so that the shielding strip connects the first and second shielding components into an integral shielding structure.

[0006] Furthermore, the shielding strip also includes a connecting portion, through which the first bend and the second bend are joined. The connecting portion has an arc-shaped structure, and compared to the arc that is tangent to both the first bend and the second bend, the arc-shaped connecting portion protrudes away from the center of the arc.

[0007] Furthermore, the shielding strip is a strip-shaped bent structure, and the length of the first bent portion is greater than the length of the second bent portion.

[0008] Furthermore, the shielding strip is provided in multiple sets, and each set of shielding strips is set at the phase-to-phase connection seam between the low-voltage riser and the low-voltage box cover to connect the phase-to-phase gap between the first shielding component and the second shielding component.

[0009] Furthermore, the shielding structure for the low-voltage side of the transformer also includes a mounting plate, which is fixedly connected to the first shielding component and the second shielding component. The mounting plate is provided with threaded holes, and the shielding strip is connected to the mounting plate by threaded fasteners to achieve a detachable connection with the first shielding component and the second shielding component.

[0010] Furthermore, the shielding strip is provided in multiple sets, and the gaps to be connected between the first shielding component and the second shielding component are respectively connected by each set of shielding strips. Each set of shielding strips includes multiple shielding strips, each shielding strip is distributed along the gap to be connected, and each shielding strip is provided with a connecting hole to connect to the corresponding mounting plate.

[0011] Furthermore, the mounting plate is provided in multiple positions, corresponding to each shielding strip, and is welded to the first shielding component and the second shielding component. The gap between adjacent shielding strips in the same group is not less than the weld width of the mounting plate.

[0012] Furthermore, the shielding structure for the low-voltage side of the transformer also includes a third shielding component and a fourth shielding component. The third shielding component covers the outer surface of the low-voltage tank cover, and the fourth shielding component covers the inner surface of the low-voltage flange.

[0013] This utility model also provides a transformer, the low-voltage side of which includes a low-voltage riser base, a low-voltage tank cover, and the aforementioned shielding structure for the low-voltage side of the transformer. The shielding structure for the low-voltage side of the transformer covers the surfaces of the low-voltage riser base and the low-voltage tank cover and is connected to form an integral shielding structure.

[0014] Furthermore, the low-pressure riser has a box-shaped structure with one open end and is made of non-magnetic material. The open end is provided with a flange. The low-pressure box cover has a plate-shaped structure and is made of non-magnetic material. The low-pressure box cover has multiple connection holes with flanges. The multiple low-pressure risers respectively connect the flanges of the open ends to the flanges of the connection holes on the low-pressure box cover and can be detachably connected.

[0015] The present invention relates to a shielding structure for the low-voltage side of a transformer. For a structure where the low-voltage riser and the low-voltage tank cover need to be detachably connected, a first shielding component and a second shielding component are used to cover the surfaces of the two components respectively. Then, a shielding strip is used to detachably connect the first shielding component and the second shielding component, thereby connecting the first shielding component and the second shielding component into an integral shielding structure.

[0016] This design does not affect the detachable connection between the low-voltage riser and the low-voltage tank cover, while ensuring the shielding completely covers both surfaces. It also connects the shielding components on each part, forming a complete copper shielding system. This effectively prevents magnetic leakage from entering the low-voltage riser and the low-voltage tank cover, providing excellent magnetic shielding and further preventing overheating caused by magnetic leakage. This enhances safety and reliability, extending the service life of the transformer equipment. It is suitable for high-current generator transformers with currents exceeding 20000A. The overall shielding structure is simple, rationally laid out, and easy to manufacture, install, and operate. Attached Figure Description

[0017] Figure 1 This is a schematic diagram of the layout of the shielding structure for the low-voltage side of the transformer in Embodiment 1 of this utility model;

[0018] Figure 2 This is a schematic diagram of the shielding strip in the shielding structure for the low-voltage side of the transformer in Embodiment 1 of this utility model;

[0019] Figure 3 This is a schematic diagram of the connection structure of the shielding strip in the shielding structure for the low-voltage side of the transformer in Embodiment 1 of this utility model.

[0020] In the diagram: 1. First shielding component; 2. Second shielding component; 3. Shielding strip; 31. First bend; 32. Second bend; 33. Connecting part; 4. Low-voltage riser seat; 5. Low-voltage box cover; 6. Mounting plate. Detailed Implementation

[0021] The technical solutions of this utility model will now be clearly and completely described with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of this utility model. All other embodiments obtained by those skilled in the art based on the embodiments of this utility model without creative effort are within the scope of this utility model.

[0022] In the description of this utility model, it should be noted that the terms "upper" and "lower" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience and simplification of the description and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this utility model.

[0023] In the description of this utility model, the terms "first", "second", and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0024] In the description of this utility model, it should be noted that, unless otherwise explicitly specified and limited, the terms "connection," "setting," "installation," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this utility model according to the specific circumstances.

[0025] Example 1

[0026] like Figure 1 As shown, the shielding structure for the low-voltage side of the transformer in this embodiment includes a first shielding component 1, a second shielding component 2, and a shielding strip 3. The first shielding component 1 covers the inner surface of the low-voltage riser 4, and the second shielding component 2 covers the inner surface of the low-voltage tank cover 5. The shielding strip 3 includes a first bent portion 31 and a second bent portion 32. The first bent portion 31 and the second bent portion 32 are joined together to form a bent shielding strip 3 structure. The first bent portion 31 is attached to and detachably connected to the first shielding component 1, and the second bent portion 32 is attached to and detachably connected to the second shielding component 2, so that the shielding strip 3 connects the first shielding component 1 and the second shielding component 2 into an integral shielding structure.

[0027] In this embodiment, for the low-pressure riser 4 and the low-pressure box cover 5 that require a detachable connection, a first shielding component 1 and a second shielding component 2 are used to cover the surfaces of the two respectively. Then, a shielding strip 3 is used to detachably connect the first shielding component 1 and the second shielding component 2, thereby connecting the first shielding component 1 and the second shielding component 2 into an integral shielding structure.

[0028] This configuration does not affect the detachable connection between the low-voltage riser 4 and the low-voltage tank cover 5, while ensuring that the shielding completely covers both surfaces. It also connects the shielding components on each part, forming a complete copper shielding system. This effectively prevents magnetic leakage from entering the low-voltage riser 4 and the low-voltage tank cover 5, providing excellent magnetic shielding and further avoiding overheating caused by magnetic leakage. This makes the system safer, more reliable, and extends the service life of the transformer. It is suitable for high-current generator transformers with currents exceeding 20,000A. Furthermore, the overall structure is simple, the layout is reasonable, and it is easy to manufacture, install, and operate.

[0029] In this embodiment, as Figure 2 As shown, the first bend 31 and the second bend 32 of the shielding strip 3 are perpendicular to each other, and the bend angle formed is a right angle, which matches the connection bend angle between the inner surface of the low-pressure riser 4 and the low-pressure box cover 5. In other embodiments, it can also be set to other angle shapes corresponding to the connection bend angle, which will not be described in detail here.

[0030] In this embodiment, the shielding strip 3 also includes a connecting portion 33. The first bent portion 31 and the second bent portion 32 are joined together through the connecting portion 33. The connecting portion 33 has an arc-shaped structure, and compared to the circular arc that is tangent to both the first bent portion 31 and the second bent portion 32, the arc-shaped connecting portion 33 protrudes away from the center of the circular arc. Compared to the sharp edges formed by direct bending, the arc-shaped connecting portion 33 can effectively avoid the formation of an electric field at the sharp bend edges, further optimizing the shielding function. The more outward-protruding arc shape can not only avoid interference with the connection bend between the inner surface of the low-voltage riser 4 and the low-voltage box cover 5, ensuring that the shielding strip 3 fits the surfaces of the first shielding component 1 and the second shielding component 2, but also give the connecting portion 33 a certain stretch margin, so that the joint between the first bent portion 31 and the second bent portion 32 has a certain degree of toughness during installation.

[0031] In this embodiment, the shielding strip 3 is a strip-shaped bent structure, and the length of the first bent portion 31 is greater than the length of the second bent portion 32. The strip-shaped structure is both lightweight and thin, and increases the contact area between the shielding strip 3 and the shielding component. The slightly longer length of the first bent portion 31 also provides some support for the low-voltage riser 4, ensuring installation stability. In this embodiment, the shielding strip 3, the first shielding component 1, the second shielding component 2, and the following mounting plate 6, third shielding component, and fourth shielding component can all be made of non-magnetic materials commonly used in transformers, such as the copper shielding material commonly used in transformers.

[0032] In this embodiment, multiple sets of shielding strips 3 are provided. Each set of shielding strips 3 is disposed at the phase-to-phase connection seam between the low-voltage riser 4 and the low-voltage box cover 5 to connect the phase-to-phase gap between the first shielding component 1 and the second shielding component 2. In this embodiment, the shielding strips 3 are arranged at the phase-to-phase position, which can effectively improve the magnetic blocking ability at the phase-to-phase gap where magnetic leakage is more likely.

[0033] In this embodiment, as Figure 3 As shown, the shielding structure for the low-voltage side of the transformer also includes a mounting plate 6. The mounting plate 6 is fixedly connected to the first shielding component 1 and the second shielding component 2. The mounting plate 6 has threaded holes (through-holes). The shielding strip 3 is connected to the mounting plate 6 by threaded fasteners (bolts) to achieve a detachable connection with the first shielding component 1 and the second shielding component 2, making installation and connection convenient. The mounting plate 6 not only provides a mounting base for the shielding strip 3, but also avoids the need to drill holes in the first shielding component 1 and the second shielding component 2, ensuring the magnetic blocking effect.

[0034] In this embodiment, multiple sets of shielding strips 3 are provided. The gaps to be connected between the first shielding component 1 and the second shielding component 2 are respectively connected by each set of shielding strips 3. Each set of shielding strips 3 includes multiple shielding strips 3, which are distributed along the gaps to be connected. Each shielding strip 3 is provided with a connecting hole, which is connected to the corresponding mounting plate 6. Compared with a whole shield, the arrangement of multiple shielding strips 3 side by side can avoid the situation where manufacturing and installation errors at each connecting hole are continuously superimposed, ultimately leading to the inability to install. Moreover, it is precisely because the superposition of errors is avoided that the installation and manufacturing precision requirements of each shielding strip 3 are greatly reduced, thereby reducing costs. The arrangement of multiple shielding strips 3 side by side can adapt to various space sizes by setting the number. In this embodiment, each set of shielding strips 3 includes five shielding strips 3. In other embodiments, the number can be selected as needed. The width and thickness of the shielding strips 3 can be specifically selected according to actual engineering requirements such as current conditions, transformer size, and inner diameter of the low-voltage riser 4, which will not be elaborated here.

[0035] In this embodiment, there are multiple mounting plates 6, which are positioned corresponding to each shielding strip 3 and are all welded to the first shielding component 1 and the second shielding component 2 (each shielding strip 3 is provided with two mounting plates 6, which are respectively connected to the first bending part 31 and the second bending part 32). The gap between adjacent shielding strips 3 in the same group should be as small as possible, but not less than the weld width of the mounting plate 6, so as to avoid the weld position.

[0036] In this embodiment, the shielding structure for the low-voltage side of the transformer also includes a third shielding component and a fourth shielding component. The third shielding component covers the outer surface of the low-voltage box cover 5, and the fourth shielding component covers the inner surface of the low-voltage flange (the low-voltage flange is an existing structural component on the low-voltage side of the transformer), thereby further improving the shielding capability.

[0037] In summary, this embodiment can be applied to the field of transformer manufacturing technology. Addressing the current problem of low-voltage overheating in high-current generator transformers, it provides a structurally sound and reliable copper shielding arrangement. Specifically, it offers a novel copper strip and shielding structure for the low-voltage side of a high-current transformer product. In this design, the low-voltage tank cover 5 and the low-voltage riser 4 are entirely made of non-magnetic steel plates. The inner wall of the low-voltage riser 4, the interior of the low-voltage flange, and the inside and outside of the low-voltage tank cover 5 are all covered with copper shielding (various shielding components). Furthermore, a copper strip (shielding strip 3) connects the copper shielding inside the low-voltage riser 4 and the low-voltage tank cover 5. The copper strip is L-shaped, with one end bolted to the copper shielding inside the low-voltage riser 4 and the other end bolted to the copper shielding inside the low-voltage tank cover 5. This effectively prevents leakage magnetic flux from entering the low-voltage tank cover 5 and the low-voltage riser 4, offering advantages such as simple structure, convenient operation, and good magnetic shielding effect.

[0038] Example 2

[0039] The transformer in this embodiment, such as Figure 1 As shown, the low-voltage side of the transformer includes a low-voltage riser 4, a low-voltage tank cover 5, and the shielding structure for the low-voltage side of the transformer in Embodiment 1. The shielding structure for the low-voltage side of the transformer covers the surfaces of the low-voltage riser 4 and the low-voltage tank cover 5 and is connected to form an integral shielding structure. The high-voltage side and low-voltage side of the transformer in this embodiment also naturally include other necessary components, but these are all conventional structures of existing transformers and are not innovative features of this embodiment, so they will not be described in detail here.

[0040] In this embodiment, the low-pressure riser 4 has a box-shaped structure with one open end and is made of non-magnetic material. A flange is provided at the open end. The low-pressure tank cover 5 has a plate-shaped structure, is made of non-magnetic material, and has multiple connection holes with flanges. Multiple low-pressure risers 4 are detachably connected by connecting their open flanges to the flanges at the respective connection holes on the low-pressure tank cover 5. This flange connection structure is a commonly used structure for risers and will not be described in detail here. Both the low-pressure riser 4 and the low-pressure tank cover 5 can be made of non-magnetic steel plate (a readily available material). The distance between each low-pressure riser 4 is the phase distance (the phase direction is conventional knowledge in this field and will not be described in detail here).

[0041] It is understood that the above embodiments are merely exemplary implementations used to illustrate the principles of this utility model, and the utility model is not limited thereto. For those skilled in the art, various modifications and improvements can be made without departing from the spirit and essence of this utility model, and these modifications and improvements are also considered to be within the protection scope of this utility model.

Claims

1. A shield structure for a low voltage side of a transformer, characterized by: Includes a first shielding component (1), a second shielding component (2), and a shielding strip (3). The first shielding element (1) covers the inner surface of the low-voltage riser (4), and the second shielding element (2) covers the inner surface of the low-voltage box cover (5). The shielding strip (3) includes a first bent portion (31) and a second bent portion (32), which are joined together to form a bent shielding strip (3) structure. The first bend (31) is attached to and detachably connected to the first shielding member (1), and the second bend (32) is attached to and detachably connected to the second shielding member (2), so that the shielding strip (3) connects the first shielding member (1) and the second shielding member (2) into an integral shielding structure.

2. The shield structure for a low voltage side of a transformer according to claim 1, characterized by: The shielding strip (3) also includes a connecting part (33), wherein the first bending part (31) and the second bending part (32) are joined together through the connecting part (33). The connecting part (33) has an arc-shaped structure, and compared with the arc that is tangent to both the first bending part (31) and the second bending part (32), the arc-shaped connecting part (33) protrudes away from the center of the arc.

3. The shielding structure for the low-voltage side of a transformer according to claim 1, characterized in that: The shielding strip (3) is a strip-shaped bent structure, and the length of the first bent part (31) is greater than the length of the second bent part (32).

4. The shielding structure for the low-voltage side of a transformer according to claim 1, characterized in that: The shielding strip (3) is provided in multiple sets. Each set of shielding strips (3) is set at the phase-to-phase joint between the low-voltage riser (4) and the low-voltage box cover (5) to connect the phase-to-phase gap between the first shielding component (1) and the second shielding component (2).

5. The shielding structure for the low-voltage side of a transformer according to claim 1, characterized in that: It also includes a mounting plate (6), which is fixedly connected to the first shielding member (1) and the second shielding member (2). The mounting plate (6) is provided with threaded holes. The shielding strip (3) is connected to the mounting plate (6) by threaded fasteners to achieve a detachable connection with the first shielding component (1) and the second shielding component (2).

6. The shielding structure for the low-voltage side of a transformer according to claim 5, characterized in that: The shielding strip (3) is provided in multiple sets. The gaps to be connected between the first shielding component (1) and the second shielding component (2) are respectively connected by each set of shielding strips (3). Each set of shielding strips (3) includes multiple shielding strips (3), each shielding strip (3) is distributed along the gap to be connected, and each shielding strip (3) is provided with a connection hole to connect to the corresponding mounting plate (6).

7. The shielding structure for the low-voltage side of a transformer according to claim 6, characterized in that: Multiple mounting plates (6) are provided, each positioned corresponding to a shielding strip (3), and all are welded to the first shielding component (1) and the second shielding component (2). The gap between adjacent shielding strips (3) in the same group shall not be less than the weld width of the mounting plate (6).

8. The shielding structure for the low-voltage side of a transformer according to claim 1, characterized in that: It also includes a third shielding component and a fourth shielding component. The third shielding element covers the outer surface of the low-pressure box cover (5). The fourth shielding element covers the inner surface of the low-pressure flange.

9. A transformer, characterized in that: The low-voltage side of the transformer includes a low-voltage riser (4), a low-voltage tank cover (5), and a shielding structure for the low-voltage side of the transformer as described in any one of claims 1 to 8. The low-voltage side of the transformer is covered by a shielding structure, which covers the surface of the low-voltage riser (4) and the low-voltage box cover (5) and is connected to form an integral shielding structure.

10. The transformer according to claim 9, characterized in that: The low-pressure riser (4) has a box-shaped structure with one open end and is made of non-magnetic material. The open end is equipped with a flange. The low-pressure box cover (5) has a plate-like structure, is made of non-magnetic material, and has multiple connection holes with flanges. The multiple low-pressure riser seats (4) respectively connect the flanges with the end openings to the flanges of the connecting holes on the low-pressure box cover (5) in a detachable manner.

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