Transformer and method for arranging a bushing of a transformer

Abstract

The present invention provides a transformer and a method for arranging bushings of the transformer. A transformer includes a coil (20) and a bushing (10) for leading out a lead wire of the coil (20) to the outside of a transformer housing (30). The bushing (10) is arranged based on a voltage gradient on the coil (20) such that: a bushing part where the highest potential of the bushing (10) is located and a coil part of the coil (20) having the same potential as the highest potential of the bushing (10) are spatially opposed. The present invention realizes a compact design of the transformer, can more effectively utilize the limited space of the transformer, and reduces the weight of the transformer and the space occupation ratio of the substation.

Description

Technical Field

[0001] The present invention generally relates to the field of electrical equipment, and more particularly, to transformers and methods of arranging bushings of transformers. Background Art

[0002] It is well known that the bushing of a transformer is a component that leads the high-voltage lead inside the transformer to the outside of the transformer housing. The lead-out wire of the transformer coil must pass through the bushing. The bushing insulates the lead-out wire from the transformer housing and at the same time plays a role in fixing the lead-out wire.

[0003] In transformer design, the size requirements for transformers are very strict. In traditional transformers, due to requirements such as high voltage level and large insulation distance of high-voltage bushings, the bushing is usually installed by means of a bushing riser, which cannot meet the requirements of customers for the size of the transformer. Summary of the Invention

[0004] In view of this, the present invention proposes a new transformer and a method of arranging bushings of the transformer. The present invention realizes a compact design of the transformer, can more effectively utilize the limited space of the transformer, and reduces the weight of the transformer and the space occupation ratio of the substation.

[0005] According to one aspect of the present invention, there is provided a transformer including a coil and a bushing for leading the lead-out wire of the coil to the outside of the transformer housing. In particular, the bushing is arranged based on the voltage gradient on the coil such that: the bushing part where the highest potential of the bushing is located and the coil part of the coil having the same potential as the highest potential of the bushing are spatially opposed.

[0006] In this way, it is realized that the bushing is arranged as close as possible to the equipotential coil components, which can reduce the insulation distance of the bushing and effectively utilize the limited space of the transformer.

[0007] Further, the bushing part where the highest potential of the bushing is located and the same-potential coil part of the coil are at the same height in the vertical direction.

[0008] In this way, it is possible to further reduce the insulation distance of the bushing and more effectively utilize the limited space of the transformer.

[0009] Further, the coil is arranged vertically along the longitudinal axis of the coil, and the bushing is arranged vertically along the longitudinal axis of the bushing.

[0010] In this way, the directions of the coil and the bushing are reasonably arranged, and while meeting the required insulation requirements, the limited space of the transformer is effectively utilized.

[0011] Further, the bushing includes a main body portion, a mounting flange connected to the main body portion, and a grading sphere located at one end of the main body portion. The bushing is mounted on a mounting seat at the top of the transformer housing by using the mounting flange. Wherein, in the mounted state, the main body portion and the grading sphere are located in the space between the side wall of the transformer housing and the iron core in the coil.

[0012] In this way, the positions of the various parts of the bushing relative to the transformer housing are reasonably arranged, effectively utilizing the limited space of the transformer while meeting the required insulation requirements.

[0013] Further, the height of the central plane of the grading sphere in the vertical direction is the same as the height of the top surface of the coil in the vertical direction; or the height of the bottom surface of the grading sphere is the same as the height of the top surface of the coil in the vertical direction.

[0014] In this way, the limited space of the transformer can be effectively utilized while meeting the required insulation requirements.

[0015] Further, the first shortest distance between the bushing part and the coil part is 30 cm to 50 cm.

[0016] In this way, while meeting the required insulation requirements, the distance between the bushing part and the coil part can be significantly reduced, thereby saving the limited space inside the transformer.

[0017] Further, the second shortest distance between the bushing part and the side wall of the transformer housing is 180 cm to 210 cm.

[0018] In this way, the limited space inside the transformer can be saved while meeting the required insulation requirements.

[0019] Further, the coil is the outermost coil, and another inner coil is also provided radially inside the outermost coil.

[0020] In this way, by reasonably arranging the position of the bushing corresponding to the lead wire of the outermost coil, the limited space inside the transformer can be saved while meeting the required insulation requirements.

[0021] Further, the mounting seat at the top of the transformer housing is provided with a recessed mounting groove, and the mounting flange of the bushing is embedded in the mounting groove.

[0022] In this way, the limited space of the transformer is reasonably utilized, realizing a compact design of the transformer.

[0023] According to another aspect of the present invention, there is provided a method for arranging bushings of a transformer. In particular, the method includes the following steps: setting a coil and determining the potential of each part of the coil; setting bushings for leading out wires of the coil to the outside of the transformer housing and determining the highest potential on the bushings; and based on the voltage gradient on the coil, arranging the bushings such that: the bushing part where the highest potential of the bushing is located and the coil part of the coil having the same potential as the highest potential of the bushing are opposed to each other spatially.

[0024] The method for arranging bushings of the present invention first determines the potential of each part of the coil, determines the part of the coil having the same potential as the relevant bushing, and then arranges the bushing as close as possible at a position equipotential with the coil, so that the distance between the bushing and the coil can be very small.

[0025] In summary, the transformer and the method for arranging bushings of the present invention at least achieve the following beneficial technical effects: while ensuring the insulation distance of the bushings of the transformer, a compact design of the transformer is realized, the limited space of the transformer can be utilized more effectively, and the weight of the transformer and the space occupation ratio of the substation are reduced. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] The following will make the above and other features and advantages of the present invention clearer to those of ordinary skill in the art by describing the preferred embodiments of the present invention in detail with reference to the accompanying drawings, wherein:

[0027] Figure 1 is a schematic cross-sectional view of a part of a transformer according to an exemplary embodiment of the present invention.

[0028] Figure 2 is Figure 1 a schematic diagram of the voltage gradient distribution of the coil of the transformer in

[0029] Figure 3 is Figure 1 a schematic diagram of the voltage gradient distribution of the bushing in

[0030] Among them, the reference numerals are as follows:

[0031] 10. Bushing;

[0032] 11. Main body part;

[0033] 12. Mounting flange;

[0034] 13. Grading sphere;

[0035] 14. Porcelain tube;

[0036] 15. Bushing lifting ring;

[0037] 20. Coil;

[0038] 21. Top surface;

[0039] 30. Transformer housing;

[0040] 31. Mounting base;

[0041] 32. Assembly component;

[0042] 33. Top;

[0043] 40. Inner layer coil;

[0044] 50. Iron core;

[0045] L1. Longitudinal axis of the bushing;

[0046] L2. Longitudinal axis of the coil;

[0047] Um. Highest potential;

[0048] Ur. Intermediate potential;

[0049] N. Neutral point;

[0050] D’. First shortest distance;

[0051] D. Second shortest distance. Detailed implementation manners

[0052] To make the objectives, technical solutions and advantages of the present invention clearer, the present invention will be further described in detail below through embodiments. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. The description of at least one exemplary embodiment below is actually only illustrative and in no way constitutes any limitation to the present invention and its application or use. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts fall within the scope of protection of the present invention.

[0053] It should be noted that the terms used herein are only for describing specific implementation manners and are not intended to limit the exemplary implementation manners according to the present application. As used herein, unless otherwise clearly specified in the context, the singular form is also intended to include the plural form.

[0054] First, refer to Figure 1 , Figure 1 which is a schematic diagram of a partially cut-away view of a transformer according to an exemplary embodiment of the present invention. Figure 1 The transformer in

[0055] includes a coil 20 and a bushing 10 for leading the lead wire of the coil 20 to the outside of the transformer housing 30. Figure 1 It can be seen fromFigure 3 ) The bushing 10 includes a main body portion 11, a mounting flange 12 connected to the main body portion 11, and a grading ball 13 located at one end of the main body portion 11. The bushing 10 is mounted on a mounting seat 31 at the top 33 of the transformer housing 30 by means of the mounting flange 12. Among them, in the mounted state, the main body portion 11 and the grading ball 13 are located in the space between the side wall of the transformer housing 30 and the iron core 50 in the coil 20. The mounting seat 31 at the top 33 of the transformer housing 30 is provided with a recessed mounting groove, and the mounting flange 12 of the bushing 10 is embedded in the mounting groove. Figure 1 Also shown is an assembly part 32 for mounting the top 33 and the side wall of the transformer housing 30 together. In addition, Figure 1 also shown are the porcelain tube 14 and the bushing lifting ring 15 of the bushing 10. However, since these components are not relevant to the aspects to be improved in the present invention, no detailed discussion will be made on these components to avoid confusion.

[0056] Those skilled in the art can understand that the lead wire (not shown) of the coil 20 is introduced into the bushing 10 through the bottom of the grading ball 13, so that the lead wire is led to the outside of the transformer housing 30 for use. An important aspect of the present invention is that the bushing 10 is arranged based on the voltage gradient on the coil 20 such that: the bushing part where the highest potential of the bushing 10 is located and the coil part of the coil 20 having the same potential as the highest potential of the bushing 10 are opposed to each other in space, that is, their positions in space are relative, which can be called an equipotential arrangement. Therefore, the insulation distance between the bushing 10 and the coil 20 can be very small. Regarding this aspect, the following will refer to Figure 2 and Figure 3 for a detailed description.

[0057] Figure 2 is Figure 1 a schematic diagram of the voltage gradient distribution of the coil 20 of the transformer in Figure 3 is Figure 1 a schematic diagram of the voltage gradient distribution of the bushing 10 in

[0058] From Figure 2 it can be seen that the coil 20 has a voltage gradient, that is, a voltage drop, from the highest potential Um to the neutral point N. The highest potential Um is located at the top of the coil 20, and the neutral point N is located at the bottom of the coil 20. In addition, Ur in the figure represents an intermediate potential, which represents a non-specific value and is an intermediate value representing the voltage drop.

[0059] From Figure 3It can be seen that the bushing 10 has the highest potential Um at the grading sphere 13. Since the lead wire (not shown) of the coil 20 is introduced into the bushing 10 through the bottom of the grading sphere 13, the potential difference between the grading sphere 13 and the top of the coil 20 is very small, and to a certain extent, this potential difference can be ignored. Therefore, the first shortest distance D' (see Figure 1 ) between the grading sphere 13 and the coil 20 can be very small, and this first shortest distance only needs to meet the requirements of the mechanical operation space of the relevant components of the transformer, such as meeting the installation operation requirements of the bushing, etc. The first shortest distance D' is, for example, 20 cm to 70 cm, preferably 40 cm to 50 cm, and for example, 45 cm.

[0060] From the above, it can be known that the highest potential Um of the coil 20 is located at the top of the coil 20, while the highest potential Um of the bushing 10 is at the position of the grading sphere 13. Therefore, in this embodiment, the top of the coil 20 and the grading sphere 13 are basically within the same vertical height range.

[0061] In addition, referring to Figure 1 , the coil 20 is vertically arranged along the longitudinal axis L2 of the coil 20, and the bushing 10 is vertically arranged along the longitudinal axis L1 of the bushing 10. Obviously, the longitudinal axis L2 of the coil and the longitudinal axis L1 of the bushing are parallel to each other. Of course, if required by the design, the directions of the two can be appropriately adjusted.

[0062] In the Figure 1 embodiment, the grading sphere 13 is columnar, and the height of the central plane of the grading sphere 13 in the vertical direction is basically the same as the height of the top surface 21 of the coil 20 in the vertical direction. Tests have proven that when this height setting is met, it can ensure that the potential of the grading sphere 13 is basically the same as the potential of the top surface 21 of the coil 20, so that the above-mentioned first shortest distance D' is as small as possible, and thus the overall height dimension of the transformer can be reduced. Alternatively, the bushing 10 can also be arranged such that: the height of the bottom surface of the grading sphere 13 is the same as the height of the top surface 21 of the coil 20, and the design purpose of the present invention can also be achieved: arranging the bushing as close as possible to the equipotential coil, which can make the above-mentioned first shortest distance D' as small as possible and effectively utilize the limited space of the transformer.

[0063] In other words, according to the specific design requirements of the transformer, the height of the grading sphere 13 relative to the top surface 21 of the coil 20 can be appropriately adjusted, and it can be slightly lowered or raised, as long as the two correspond to each other in spatial position and the bushing is arranged near the equipotential coil part.

[0064] Please continue to refer to Figure 1, for example, in the case of a voltage level of 220 kV, the second shortest distance D between the grading sphere 13 and the side wall of the transformer housing 30 can be 150 cm to 240 cm, preferably: 180 cm to 210 cm, for example, 200 cm. It should be noted that the coil 20 is the outermost coil, and another inner coil 40 can also be provided in this outermost coil. Since the outermost coil surrounds the inner coil 40, therefore, only by satisfying the above-mentioned equipotential arrangement between the grading sphere 13 of the bushing 10 and the coil 20 can the object of the present invention be achieved, without considering the voltage of the inner coil.

[0065] To understand the solution of the present invention more clearly, the method of arranging the bushing of the transformer will be described below. This method includes the following steps: arranging the coil 20 and determining the potential of each part of the coil 20; arranging the bushing 10 for leading the lead wire of the coil 20 to the outside of the transformer housing 30 and determining the highest potential on the bushing 10; and based on the voltage gradient on the coil 20, arranging the bushing 10 such that: the bushing part where the highest potential of the bushing 10 is located and the coil part of the coil 20 having the same potential as the highest potential of the bushing 10 are opposed to each other in space. By this arrangement method, while ensuring the insulation distance of the bushing 10 of the transformer, a compact design of the transformer is achieved, the limited space of the transformer can be utilized more effectively, and the weight of the transformer and the space occupation ratio of the substation are reduced.

[0066] The above are only the preferred embodiments of the present application and are not used to limit the present application. For those skilled in the art, various changes and modifications can be made to the present application. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. A transformer, comprising a coil (20) and a bushing (10) for leading out the lead wire of the coil (20) to the outside of the transformer housing (30), characterized in that, The bushing (10) is arranged based on the voltage gradient on the coil (20) such that: the bushing part where the highest potential of the bushing (10) is located and the coil part of the coil (20) having the same potential as the highest potential of the bushing (10) are spatially opposed; Wherein, the bushing (10) includes a main body part (11), a mounting flange (12) connected to the main body part (11), and a grading sphere (13) located at one end of the main body part (11). The bushing (10) is mounted on a mounting seat (31) at the top (33) of the transformer housing (30) by using the mounting flange (12). Wherein, in the mounted state, the main body part (11) and the grading sphere (13) are located in the space between the side wall of the transformer housing (30) and the iron core (50) in the coil (20); Wherein, the coil (20) has a voltage gradient from the highest potential to the neutral point. The highest potential of the coil is located at the top of the coil (20), and the neutral point is located at the bottom of the coil (20); And wherein, the highest potential of the bushing (10) is at the grading sphere position, and the top of the coil (20) and the grading sphere are within the same vertical height range.

2. The transformer according to claim 1, characterized in that, The bushing part where the highest potential of the bushing (10) is located and the coil part of the coil (20) having the same potential are at the same height in the vertical direction.

3. The transformer according to claim 1 or 2, characterized in that, The coil (20) is vertically arranged along the longitudinal axis (L2) of the coil (20), and the bushing (10) is vertically arranged along the longitudinal axis of the bushing (10).

4. The transformer according to claim 3, characterized in that, The height of the central plane of the grading sphere (13) in the vertical direction is the same as the height of the top surface (21) of the coil (20) in the vertical direction; or the height of the bottom surface of the grading sphere (13) is the same as the height of the top surface (21) of the coil (20) in the vertical direction.

5. The transformer according to claim 1 or 2, characterized in that, The first shortest distance (D') between the bushing part and the coil part is 40 cm to 50 cm.

6. The transformer according to claim 1 or 2, characterized in that, The second shortest distance (D) between the bushing part and the side wall of the transformer housing is 180 cm to 210 cm.

7. The transformer according to claim 1 or 2, characterized in that, The coil (20) is the outermost coil, and another inner coil (40) is further provided radially inside the outermost coil.

8. The transformer according to claim 1, characterized in that, The mounting seat (31) at the top (33) of the transformer housing (30) is provided with a recessed mounting groove, and the mounting flange (12) of the bushing (10) is embedded in the mounting groove.

9. A method for arranging bushings of a transformer, characterized in that, The method includes the following steps: Setting the coil (20) and determining the potential of each part of the coil (20); Setting the bushing (10) for leading the lead wire of the coil (20) to the outside of the transformer housing (30) and determining the highest potential on the bushing (10); and based on the voltage gradient across the coil (20), arranging the bushing (10) such that: the bushing part with the highest potential of the bushing (10) and the coil part of the coil (20) having the same potential as the highest potential of the bushing (10) are spatially opposed to each other, wherein the bushing (10) includes a main body part (11), a mounting flange (12) connected to the main body part (11), and a grading sphere (13) located at one end of the main body part (11), and the bushing (10) is mounted on a mounting seat (31) at the top (33) of the transformer housing (30) by using the mounting flange (12), and in the mounted state, the main body part (11) and the grading sphere (13) are located in the space between the side wall of the transformer housing (30) and the iron core (50) in the coil (20); wherein the coil (20) has a voltage gradient from the highest potential to the neutral point, the highest potential of the coil is located at the top of the coil (20), and the neutral point is located at the bottom of the coil (20); and wherein the highest potential of the bushing (10) is at the grading sphere position, and the top of the coil (20) and the grading sphere are within the same vertical height range.

Images