A 35kV transformer high voltage coil structure and transformer

Abstract

The utility model discloses a kind of 35kV transformer high voltage coil structure, 35kV transformer high voltage coil structure includes core column and two coil modules wound in core column, coil module includes first unit coil, air passage and second unit coil sequentially arranged from inside to outside, first unit coil is equipped with first welding point and second welding point, second unit coil is equipped with third welding point and fourth welding point, first welding point and third welding point, second welding point and fourth welding point are welded by the welding line of air passage across;Compared with the welding line in prior art passes through air passage multiple times, by changing the winding mode of coil, only two welding points are realized at place, effectively reduce welding spot, reduce working hours, reduce the technical hidden danger caused by too many welding spots and possible processing of unqualified welding spot, voltage between cross-line segments is halved, corresponding inter-segment electric field intensity is halved under the same inter-segment spacing, thereby greatly reduce partial discharge, beneficial to prolong service life.

Description

Technical Field

[0001] This utility model relates to the technical field of transformers, specifically a 35kV transformer high-voltage coil structure and transformer. Background Technology

[0002] A transformer is a static electrical device used to exchange alternating voltage and current to transmit alternating current electrical energy. Due to its high efficiency in transmission, it is widely used in power plants and substations. With increasing social attention to energy conservation and charging piles, transformers are playing an increasingly important role.

[0003] As engineering production demands higher product performance, the types of transformers are gradually increasing. However, there are technical risks associated with conventional high-voltage coil winding methods. Conventional winding of 35kV transformers results in too many solder joints in the high-voltage coil structure. This increases welding time and the probability of partial discharge failure due to improper welding. Furthermore, the high inter-section voltage can lead to excessively high inter-section electric field strength, which can cause significant partial discharge.

[0004] Partial discharge causes coil insulation aging, and the electrolytic effect of partial discharge leads to accelerated oxidation and corrosion of the insulation, thereby reducing the service life of the transformer. Therefore, it is necessary to design a 35kV transformer high-voltage coil structure to address the above problems. Utility Model Content

[0005] This invention aims to solve at least one of the technical problems existing in the prior art. To this end, this invention provides a 35kV transformer high-voltage coil structure and a transformer, solving the problems of excessive solder joints and excessively high inter-section voltage in existing 35kV transformer high-voltage coil structures.

[0006] A 35kV transformer high-voltage coil structure according to a first aspect of the present invention includes:

[0007] Core post;

[0008] The coil module has two coils wound around the core post. The coil module includes a first unit coil, an air passage, and a second unit coil arranged sequentially from the inside to the outside. The first unit coil has a first welding point and a second welding point, and the second unit coil has a third welding point and a fourth welding point. The first welding point and the third welding point, as well as the second welding point and the fourth welding point, are welded together by a welding line that crosses the air passage.

[0009] A 35kV transformer high-voltage coil structure according to an embodiment of the present invention has at least the following beneficial effects:

[0010] This utility model embodiment reduces the number of inclined wires passing through the air passage through a new winding method, which greatly reduces the number of solder joints. This not only reduces the technical risks caused by too many solder joints and the possibility of substandard solder joints, but also halves the voltage between line segments. Correspondingly, the electric field strength between segments is halved under the same segment spacing, thereby significantly reducing partial discharge and effectively avoiding the problem of reduced transformer lifespan caused by coil insulation aging due to partial discharge. In addition, the reduction in solder joints reduces processing costs and saves manpower.

[0011] According to some embodiments of the present invention, the first unit coil includes a plurality of first wire segments connected in sequence, and the second unit coil includes a plurality of second wire segments connected in sequence, wherein the number of the first wire segments and the number of the second wire segments are the same.

[0012] According to some embodiments of the present invention, each pair of adjacent first conductor segments is connected by a guy wire, and each pair of adjacent second conductor segments is connected by a guy wire.

[0013] According to some embodiments of the present invention, the first conductor segment includes a plurality of first conductor layers connected in sequence, and the second conductor segment includes a plurality of second conductor layers connected in sequence.

[0014] According to some embodiments of the present invention, the number of conductor layers in each first conductor segment is the same, and the number of conductor layers in each second conductor segment is the same.

[0015] According to some embodiments of the present invention, the two coil modules are arranged symmetrically up and down along the axis, and the ends of the two coil modules that are close to each other are located in the middle section of the core column.

[0016] According to some embodiments of this utility model, the first conductor segment at one end of the two coil modules that are close to each other is a tap segment, and each conductor layer of the tap segment has several taps.

[0017] According to some embodiments of the present invention, the first conductor segment of the first unit coil that is away from the tap segment is the first and last segment, and the outermost first conductor layer corresponding to the first and last segment has a common connector, and the tap segment and the common connector are aligned.

[0018] According to some embodiments of the present invention, several of the taps and the common tap are disposed on the outer layer of the coil module.

[0019] A transformer according to a second aspect of the present invention includes: the high-voltage coil structure described above.

[0020] Other features and advantages of this invention will be set forth in the description which follows, and will be apparent in part from the description, or may be learned by practicing the invention. Attached Figure Description

[0021] The present invention will be further described below with reference to the accompanying drawings and embodiments, wherein:

[0022] Figure 1 This is a schematic diagram of half a coil in the existing 35kV transformer high-voltage coil structure;

[0023] Figure 2 A schematic diagram of one embodiment of the 35kV transformer high-voltage coil structure provided by this utility model;

[0024] Figure 3 The 35kV transformer high-voltage coil structure provided in this embodiment of the utility model Figure 2 A schematic diagram of the number of turns distribution in the illustrated embodiment.

[0025] Icon labels:

[0026] Coil module 1;

[0027] First unit coil 100; first conductor segment 110; first conductor layer 111; first solder joint 120; second solder joint 130; common connector 140; tap joint 150;

[0028] Air passage 200; welding line 210;

[0029] Second unit coil 300; second conductor segment 310; second conductor layer 311; third solder point 320; fourth solder point 330. Detailed Implementation

[0030] The embodiments of this utility model are described in detail below. Examples of these embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain this utility model, and should not be construed as limiting this utility model.

[0031] In the description of this utility model, it should be understood that the orientation descriptions, such as up, down, etc., are based on the orientation or positional relationship shown in the drawings. They are only for the convenience of describing this utility model and simplifying 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.

[0032] In the description of this utility model, "multiple" refers to two or more. The use of "first" and "second" is for distinguishing technical features only and should not be construed as indicating or implying relative importance, or implicitly indicating the number of technical features or their sequential relationship.

[0033] In the description of this utility model, unless otherwise explicitly defined, terms such as "setting," "installation," and "connection" should be interpreted broadly, and those skilled in the art can reasonably determine the specific meaning of the above terms in this utility model in conjunction with the specific content of the technical solution.

[0034] The technical solution of this utility model will be clearly and completely described below with reference to the accompanying drawings. Obviously, the embodiments described below are some embodiments of this utility model, not all embodiments.

[0035] A transformer is a static electrical device used to exchange alternating voltage and current to transmit alternating current electrical energy. Due to its high efficiency in transmission, it is widely used in power plants and substations. With increasing social attention to energy conservation and charging piles, transformers are playing an increasingly important role.

[0036] As engineering production demands higher product performance, the types of transformers are gradually increasing. However, there are technical risks associated with ordinary high-voltage coil winding methods. (Referring to...) Figure 1 As shown, in the existing winding structure of the 35kV transformer high-voltage coil, each conductor segment needs to be connected by welding wire 210 at the air passage 200, resulting in too many welding points. Thirteen welding points are required in half of the coil. On the one hand, this increases the welding time, and on the other hand, it easily increases the probability of partial discharge failure due to improper welding. In addition, due to the excessively high inter-segment voltage, the corresponding inter-segment electric field strength is likely to be too high, which can easily cause a large partial discharge problem.

[0037] Partial discharge causes coil insulation aging, and the electrolytic effect of partial discharge leads to accelerated oxidation and corrosion of the insulation, thereby reducing the service life of the transformer. Therefore, it is necessary to design a 35kV transformer high-voltage coil structure to address the above problems.

[0038] To address the aforementioned issues, this invention proposes a 35kV transformer high-voltage coil structure, which effectively solves the problems of excessive solder joints and excessively high inter-section voltage in existing 35kV transformer high-voltage coil structures.

[0039] refer to Figure 2 and Figure 3 As shown, the 35kV transformer high-voltage coil structure of this utility model is illustrated in the following embodiments:

[0040] The 35kV transformer high-voltage coil structure of this utility model embodiment includes a core column and a coil module 1. The coil module 1 is covered with an insulating shell, which is generally a cylindrical structure.

[0041] Reference Figure 2 As shown, there are two coil modules 1, which are wound on the core post respectively. The two coil modules 1 are arranged symmetrically up and down along the axis, and the ends of the two coil modules 1 that are close to each other are located in the middle section of the core post.

[0042] Furthermore, the coil module 1 includes a first unit coil 100, an air passage 200, and a second unit coil 300 arranged sequentially from the inside to the outside. By setting the air passage 200 between the first unit coil 100 and the second unit coil 300, heat dissipation of the first unit coil 100 and the second unit coil 300 is facilitated, so as to avoid affecting the transformer performance due to temperature rise and ensure the working stability of the first unit coil 100 and the second unit coil 300.

[0043] Specifically, regarding the construction of the first unit coil 100 and the second coil, the first unit coil 100 includes a plurality of first wire segments 110 connected in sequence, and the second unit coil 300 includes a plurality of second wire segments 310 connected in sequence. The number of first wire segments 110 and the number of second wire segments 310 are the same. In this embodiment of the present invention, the first unit coil 100 includes six wire segments arranged at intervals, and the second unit coil 300 includes six wire segments arranged at intervals. The plurality of wire segments in the first unit coil 100 and the second unit coil 300 are arranged one-to-one on both sides of the air passage 200, so that the coil module 1 has neat wiring and a simple structure.

[0044] In some other embodiments, the number of the first conductor segment 110 and the number of the second conductor segment 310 can be adjusted and designed according to actual usage requirements and transformer capacity.

[0045] The first conductor segment 110 includes a plurality of first conductor layers 111 connected in sequence, and the second conductor segment 310 includes a plurality of second conductor layers 311 connected in sequence. In this embodiment of the present invention, the number of conductor layers in each first conductor segment 110 is the same, and the number of conductor layers in each second conductor segment 311 is the same. The first conductor layer 111 has nine layers, and the second conductor layer 311 has five layers, so as to make the voltage distribution between segments balanced and avoid excessive field strength between local segments leading to partial discharge. In addition, this design makes the wiring neat and facilitates the formation of a regular structure for assembly in the transformer.

[0046] In some other embodiments, the number of the first conductor layer 111 and the second conductor layer 311 can be adjusted and designed according to actual usage requirements and transformer capacity, etc.

[0047] The use of guy wires to connect two adjacent first conductor segments 110 and two adjacent second conductor segments 310 reduces the number of conductor welds between segments, improves process quality, reduces working time, and effectively avoids the probability of partial discharge failure due to improper welding. In addition, because the tail end of each conductor segment is connected to the head end of the next conductor segment through guy wire connection, compared to the method of connecting the head end to the head end or the tail end to the tail end, the number of conductor layers between segments is halved, and the voltage between segments is reduced accordingly. This helps to reduce partial discharge and prevent the problem of accelerated insulation aging of coils caused by partial discharge.

[0048] Furthermore, the first conductor segment 110 at the end of the two coil modules 1 that is close to each other is a tap segment. Each conductor layer of the tap segment has several taps 150. By adopting the method of internal taps, the leakage magnetic field distribution of the coil module 1 can be changed without increasing the difficulty of the process, thereby improving the performance indicators of the coil module 1, especially the short-circuit impedance of the transformer.

[0049] The first conductor segment 110 of the first unit coil 100, which is far from the tap section, is the first and last segment. The outermost first conductor layer 111 corresponding to the first and last segment has a common connector 140. The tap 150 and the common connector 140 cooperate to complete the on-load voltage regulation. By connecting the common connector 140 and one of the multiple taps 150 respectively, the voltage between the wiring can be adjusted to meet the application requirements of transformer voltage regulation.

[0050] Furthermore, several taps 150 and a common connector 140 are located on the outer layer of the coil module 1 to facilitate connection to external devices.

[0051] The first unit coil 100 has a first welding point 120 and a second welding point 130, and the second unit coil 300 has a third welding point 320 and a fourth welding point 330. The first welding point 120 and the third welding point 320, and the second welding point 130 and the fourth welding point 330 are welded together by welding lines 210 that cross the air passage 200. Compared with the traditional 35kV transformer high-voltage coil winding method, in which multiple first conductor segments 110 and multiple second conductor segments 310 are welded by welding lines 210 respectively, in this utility model embodiment, only welding lines 210 that pass through the air passage 200 twice are used, which greatly reduces the number of welding points, saves time, and reduces the probability of partial discharge failure due to improper welding. The inter-segment voltage decreases as the number of layers in the conductor segment decreases, and the inter-segment field strength decreases, which helps to avoid insulation aging problems caused by partial discharge.

[0052] In this embodiment of the utility model, reference is made to Figure 2As shown, the wires are wound from the beginning and end towards the inside to form four first wire segments 110 connected to the first welding point 120. The first welding point 120 is located at the end of the fourth first wire segment 110 from the outside to the inside. The beginning of the second wire segment 310 closest to the outside of the second unit coil 300 is the third welding point 320. The first welding point 120 and the third welding point 320 are welded by the welding line 210 passing through the air passage 200 to realize the connection between the first unit coil 100 and the second unit coil 300.

[0053] The wires of the second unit coil 300 are wound from the outermost side to the inner side, forming multiple second wire segments 310. The fourth and fifth second wire segments 310 from the outside to the inside are not connected by a diagonal guy wire, but are welded by a welding wire 210 to adjust the winding direction of the wires, so that the wires are neatly arranged and do not cross or intersect, avoiding the safety hazards caused by short circuits at the wire ends. The first end of the second wire segment 310 closest to the innermost side of the second unit coil 300 is the fourth welding point 330. The end of the fifth first wire segment 110 from the outside to the inside of the first unit coil 100 is the second welding point 130. The second welding point 130 and the fourth welding point 330 are welded by a welding wire 210 passing through the air passage 200, realizing the connection between the first unit coil 100 and the second unit coil 300.

[0054] In some other embodiments, the positions of the first welding point 120, the second welding point 130, the third welding point 320, and the fourth welding point 330 can be other positions, as long as the welding line 210 only passes through the air passage 200 twice.

[0055] In summary, this utility model embodiment provides a 35kV transformer high-voltage coil structure. By adjusting the winding method of the coil structure, the number of times the conductor passes through the air passage 200 is reduced, thus having the following advantages: effectively reducing the number of welding points and welding time; on the other hand, reducing the probability of partial discharge failure due to improper welding; in addition, due to excessively high inter-segment voltage, the corresponding inter-segment electric field strength is prone to be too high, which can easily cause large partial discharge problems. By reducing the number of conductor layers between conductor segments, the inter-segment voltage is reduced, thereby reducing the inter-segment electric field strength, optimizing the coil insulation aging problem caused by partial discharge, avoiding the electrolytic effect of partial discharge that leads to accelerated oxidation and corrosion of the insulation, thereby extending the service life of the transformer and improving the performance of the transformer.

[0056] This utility model embodiment also proposes a transformer, which is a dry-type transformer. The high-voltage coil adopts the above-mentioned 35kV transformer high-voltage coil structure. See the schematic diagram of the high-voltage coil taps. Figure 3 As shown, it possesses all the advantages of the aforementioned 35kV transformer high-voltage coil structure, which will not be elaborated upon here.

[0057] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "illustrative embodiment," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the present invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0058] The embodiments of the present utility model have been described in detail above with reference to the accompanying drawings. However, the present utility model is not limited to the above embodiments. Within the scope of knowledge possessed by those skilled in the art, various changes can be made without departing from the spirit of the present utility model.

Claims

1. A 35 kV transformer high voltage coil structure, characterized by, It comprises: a core column; a coil module, which is provided with two parallel coils on the core column, and comprises a first unit coil, an air channel and a second unit coil arranged in sequence from inside to outside, the first unit coil is provided with a first welding point and a second welding point, the second unit coil is provided with a third welding point and a fourth welding point, and the first welding point and the third welding point, the second welding point and the fourth welding point are welded by a welding line spanning the air channel.

2. The high-voltage coil structure according to claim 1, characterized in that: the first unit coil comprises a plurality of first wire segments connected in sequence, and the second unit coil comprises a plurality of second wire segments connected in sequence, and the number of the first wire segments is the same as that of the second wire segments.

3. The high-voltage coil structure according to claim 2, characterized in that: each two adjacent first wire segments are connected by a diagonal cable, and each two adjacent second wire segments are connected by a diagonal cable.

4. The high-voltage coil structure according to claim 2, characterized in that: the first wire segment comprises a plurality of first wire layers connected in sequence, and the second wire segment comprises a plurality of second wire layers connected in sequence.

5. The high-voltage coil structure according to claim 3, characterized in that: the number of wire layers in each first wire segment is the same, and the number of wire layers in each second wire segment is the same.

6. The high-voltage coil structure according to claim 2, characterized in that: the two coil modules are arranged in axial symmetry, and the ends of the two coil modules close to each other are located in the middle of the core column.

7. The high-voltage coil structure according to claim 6, characterized in that: the first wire segment at the end of the two coil modules close to each other is a tapping segment, and each wire layer of the tapping segment has a plurality of tapping heads.

8. The high-voltage coil structure according to claim 7, characterized in that: the first wire segment of the first unit coil away from the tapping segment is a first and last segment, and the outermost first wire layer corresponding to the first and last segment has a common head, and the tapping head and the common head are matched.

9. The high-voltage coil structure according to claim 8, characterized in that: a plurality of the tapping heads and the common head are provided on the outer layer of the coil module.

10. A transformer, characterized in that: it comprises the high-voltage coil structure according to any one of claims 1 to 9.

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