Winding resistance balancing structure and transformer

Abstract

The utility model discloses a winding resistance balance structure and a transformer, relates to the technical field of transformers, aims to solve the problem of high unbalance rate of three-phase winding resistance of the transformer, and adopts the technical scheme that the winding resistance balance structure comprises an X-phase lead bar and an X-phase outlet bar which are connected with an X-phase winding; the Y-phase lead bar and the Y-phase outlet bar are connected with the Y-phase winding; the Z-phase lead bar and the Z-phase outlet bar are connected with the Z-phase winding; the first tail row is connected with the X-phase lead row, the Y-phase lead row and the Z-phase lead row, and the second tail row is connected with the X-phase lead row and the Z-phase lead row. According to the utility model, the two tail rows of the transformer are connected in parallel, the first tail row is connected with the three-phase lead row, and the second tail row is only electrically connected with the X-phase lead row and the Z-phase lead row, so that the difference between the resistance between the XZ phase and the resistance between the XY phase and the YZ phase is reduced, and the unbalance rate of the resistance can be effectively reduced.

Description

Technical Field

[0001] The utility model relates to the technical field of transformers, and more specifically, to a winding resistance balancing structure and a transformer. Background Art

[0002] Unbalanced DC resistance of transformer will cause circulating current between phases or between phases and ground. When the DC resistance of three-phase windings of transformer is inconsistent, even when AC voltage is balanced, the resistance difference will cause uneven current distribution, thus generating circulating current. This circulating current will not only increase winding resistance loss, but also cause local overheating. In the long run, it may accelerate insulation aging, reduce transformer service life, and even cause failure in extreme cases.

[0003] In the prior art, the transformer using lead bars directly connects the lead bars of the three-phase windings to the first tail bar and the second tail bar respectively. This structure is difficult to reduce the deviation of the transformer DC resistance unbalance rate and will increase the resistance loss of the transformer during use. Utility Model Content

[0004] In view of the deficiencies in the prior art, the utility model provides a winding resistance balancing structure and a transformer, aiming to reduce the unbalance rate of the transformer DC resistance and reduce the winding resistance loss.

[0005] The above technical purpose of the utility model is achieved through the following technical solutions: a winding resistance balancing structure, including: an X-phase lead row and an X-phase outgoing line row connected to the X-phase winding; a Y-phase lead row and a Y-phase outgoing line row connected to the Y-phase winding; a Z-phase lead row and a Z-phase outgoing line row connected to the Z-phase winding; a first tail row; a second tail row; the first tail row connects the X-phase lead row, the Y-phase lead row and the Z-phase lead row, and the second tail row connects the X-phase lead row and the Z-phase lead row.

[0006] Optionally, the first tail row and the second tail row are arranged side by side with an interval, the X-phase lead row is provided with an X-phase plane connection portion; the Y-phase lead row is provided with a Y-phase plane connection portion; the Z-phase lead row is provided with a Z-phase plane connection portion; the X-phase plane connection portion, the Y-phase plane connection portion and the Z-phase plane connection portion are simultaneously abutted against the first tail row and the second tail row; the Y-phase plane connection portion is located between the X-phase plane connection portion and the Z-phase plane connection portion; an insulating part is provided in the area where the second tail row abuts against the Y-phase plane connection portion, so that the second tail row is insulated and connected to the Y-phase plane connection portion.

[0007] Optionally, the insulating member is insulating paper.

[0008] Optionally, the X-phase outgoing line bar and the Z-phase outgoing line bar are both connected to a transition bar.

[0009] Optionally, the transition bar and the Y-phase outgoing line bar are both connected with a copper bar soft connector.

[0010] Optionally, the copper busbar is softly connected to the bushing.

[0011] The utility model also provides a transformer, comprising the winding resistance balancing structure.

[0012] Optionally, the transformer comprises an iron core, and the X-phase winding, the Y-phase winding and the Z-phase winding are mounted on the iron core.

[0013] The utility model adopts two tail bars of the transformer in parallel, wherein the first tail bar is connected to the three-phase lead bar, and the second tail bar is electrically connected only to the X-phase lead bar and the Z-phase lead bar, thereby reducing the difference between the XZ phase resistance and the XY phase resistance, and the difference between the XZ phase resistance and the YZ phase resistance, and can effectively reduce the resistance unbalance rate. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] The accompanying drawings are used to provide a further understanding of the present invention and constitute a part of the specification. Together with the embodiments of the present invention, they are used to explain the present invention and do not constitute a limitation of the present invention. In the accompanying drawings:

[0015] Figure 1 It is a schematic diagram of the structure of the winding, the lead row, the first tail row and the second tail row in the prior art;

[0016] Figure 2 is an equivalent circuit diagram of the prior art;

[0017] Figure 3 It is a structural schematic diagram of a winding resistance balance structure;

[0018] Figure 4 It is a schematic diagram of the structure of the winding, the lead row, the first tail row and the second tail row in the embodiment of the utility model;

[0019] Figure 5 It is an equivalent circuit diagram in the embodiment of the utility model;

[0020] Figure 6 It is a schematic diagram of the X-phase lead row structure;

[0021] Figure 7 for Figure 3 A partial enlarged view of the middle part;

[0022] Figure 8 This is a schematic diagram of the structure of a transformer with a winding resistance balance structure.

[0023] Description of Figure Numbers:

[0024] Label name Label name 1 X-phase winding 302 Z phase outlet row 101 X-phase lead row 303 Z-phase plane connection 102 X-phase outgoing line row 4 First rear row 103 X-phase plane connection 5 Second rear row 2 Y phase winding 6 Insulation 201 Y-phase lead row 7 Transition row 202 Y-phase outlet row 8 Copper busbar soft connection 203 Y-phase plane connection 9 casing 3 Z phase winding 10 Iron Core 301 Z phase lead row DETAILED DESCRIPTION

[0025] The following is a description of the implementation of the present invention by means of specific embodiments. People familiar with the art can easily understand other advantages and effects of the present invention from the contents disclosed in this specification.

[0026] It should be noted that the structures, proportions, sizes, etc. illustrated in the drawings of this specification are only used to match the contents disclosed in the specification for people familiar with this technology to understand and read, and are not used to limit the limiting conditions that can be implemented in this utility model, so they have no substantial technical significance. Any modification of the structure, change of the proportional relationship or adjustment of the size, without affecting the effects that can be produced by the utility model and the purposes that can be achieved, should still fall within the scope of the technical content disclosed in this utility model. At the same time, the terms such as "upper", "lower", "left", "right", "middle" and "one" quoted in this specification are only for the convenience of description, and are not used to limit the scope of the implementation of this utility model. The change or adjustment of their relative relationship, without substantial change in the technical content, should also be regarded as the scope of the implementation of this utility model. The specific structure can be described with reference to the drawings of the patent application.

[0027] In order to solve the above technical problems, the utility model discloses a winding resistance balancing structure, such as Figure 3 and 4 As shown, it includes: an X-phase lead row 101 and an X-phase outgoing line row 102 connected to the X-phase winding 1; a Y-phase lead row 201 and a Y-phase outgoing line row 202 connected to the Y-phase winding 2; a Z-phase lead row 301 and a Z-phase outgoing line row 302 connected to the Z-phase winding 3; a first tail row 4; a second tail row 5; the first tail row 4 connects the X-phase lead row 101, the Y-phase lead row 201 and the Z-phase lead row 301, and the second tail row 5 connects the X-phase lead row 101 and the Z-phase lead row 301.

[0028] In the prior art, the first tail row 4 is connected to the X-phase lead row 101, the Y-phase lead row 201 and the Z-phase lead row 301. The equivalent circuit is as follows: Figure 2 As shown, a, b, c are lead wires of phases X, Y, and Z respectively, Rxy is the resistance of the first tail row 4 connecting the middle section of phases X and Y, and Ryz is the resistance of the first tail row 4 connecting the middle section of phases Y and Z. Knowing that Rxy = Ryz, the interphase resistance value is calculated as follows: Rab = Rxy, Rbc = Rxy, Rac = 2Rxy; and Rac-Rab = Rxy is obtained.

[0029] In this embodiment, the first tail row 4 is connected to the X-phase lead row 101, the Y-phase lead row 201 and the Z-phase lead row 301, and the second tail row 4 is connected to the X-phase lead row 101 and the Z-phase lead row 301. The equivalent circuit is as follows: Figure 5As shown in the figure, where R’ is the resistance of the second tail row 5 connecting the middle sections of the X-phase and Z-phase.

[0030] In a preferred embodiment provided by the present utility model, the position where the Y-phase lead row 201 is connected to the first tail row 4 is in the middle of the X-phase lead row 101 and the Z-phase lead row 301. Therefore, Rxy’ = 1 / 2Rxy; Ryz’ = 1 / 2Ryz; R’ = 2Rxy. Then the inter-phase resistance values are calculated as follows:

[0031] Rab’ = Rxy’ * (R’ + Ryz’) / (Rxy’ + Ryz’ + R’) = 5 / 12Rxy

[0032] Rbc’ = Ryz’ * (R’ + Rxy’) / (Rxy’ + Ryz’ + R’) = 5 / 12Rxy

[0033] Rac’ = R’ * (Rxy’ + Ryz’) / (Rxy’ + Ryz’ + R’) = 2 / 3Rxy;

[0034] It is obtained that: Rac’ - Rab’ = 1 / 4Rxy < Rac - Rab, that is, the difference between the XZ inter-phase resistance and the XY inter-phase resistance in this embodiment is smaller than that in the prior art.

[0035] In this embodiment, the first tail row 4 is connected to the three-phase leads, and the second tail row 5 is only connected to the X-phase lead row 101 and the Z-phase lead row 301, reducing the difference between the XZ inter-phase resistance and the XY inter-phase resistance, and the difference between the XZ inter-phase resistance and the YZ inter-phase resistance. Compared with the prior art, the difference between the inter-phase resistances is smaller, the resistance imbalance rate can be reduced, and each inter-phase resistance is reduced, which can reduce the resistance loss of the winding.

[0036] Furthermore, as Figure 3-4 、 Figure 6-7 shown, in an embodiment of the present utility model, the first tail row 4 and the second tail row 5 are arranged side by side at intervals. The X-phase lead row 101 is provided with an X-phase planar connection portion 103; the Y-phase lead row 201 is provided with a Y-phase planar connection portion 203; the Z-phase lead row 301 is provided with a Z-phase planar connection portion 303; the X-phase planar connection portion 103, the Y-phase planar connection portion 203 and the Z-phase planar connection portion 303 are simultaneously in contact with the first tail row 4 and the second tail row 5; the Y-phase planar connection portion 203 is located in the middle of the X-phase planar connection portion 103 and the Z-phase planar connection portion 303; an insulating member 6 is provided in the area where the second tail row 5 is in contact with the Y-phase planar connection portion 203, so that the second tail row 5 is insulated and connected to the Y-phase planar connection portion 203.

[0037] Thus, in this embodiment, the first tail row 4 and the second tail row 5 are arranged side by side at intervals, a plane connection portion is arranged on the lead row, and the plane connection portion is connected to the first tail row 4 and the second tail row 5 at the same time, and an insulating member 6 is used to isolate the second tail row 5 and the Y-phase plane connection portion 203, so that the second tail row 5 and the Y-phase plane connection portion 203 are insulated and abutted. Thus, the structures of the X-phase lead row 101, the Y-phase lead row 201, and the Z-phase lead row 301 can be the same, and can be connected to the winding without distinction, which is convenient for improving assembly efficiency.

[0038] Further, such as Figure 7 As shown, in one embodiment of the present invention, the insulating member 6 is insulating paper.

[0039] Preferably, the insulating paper is wrapped around the middle of the second tail row 5 and then tied with a shrink tape. The insulating paper used in this embodiment has the advantages of low cost and thin paper. The insulating paper wrapped around the second tail row 5 will not affect the transformer lead row structure.

[0040] Further, such as Figure 3 As shown, in one embodiment of the present invention, both the X-phase outgoing line bar 102 and the Z-phase outgoing line bar 302 are connected to a transition bar 7 .

[0041] The transition bar 7 leads the outgoing line bar to the same outlet port, which is convenient for connection with the power system. The transition bar 7 has good electrical conductivity and corrosion resistance, can adapt to use in various environments, and ensure that the electrical performance meets the needs of long-term safe operation.

[0042] Further, such as Figure 3 As shown, in one embodiment of the present invention, the transition bar 7 and the Y-phase outgoing line bar 202 are both connected with a copper bar soft connector 8 .

[0043] The copper busbar flexible connection 8 can bend naturally to a certain extent to adapt to the thermal expansion or mechanical displacement of the equipment, reduce the mechanical stress caused by the hard connection, thereby protecting the electrical equipment from damage and ensuring the firmness and durability of the electrical connection.

[0044] Further, such as Figure 3 As shown, in one embodiment of the utility model, the copper busbar flexible connection 8 is connected to the sleeve 9.

[0045] The bushing 9 can ensure that the lead wire has sufficient insulation when passing through the transformer tank, and fixes the lead wire to prevent the lead wire from being displaced due to mechanical force or electromagnetic force.

[0046] This embodiment also provides a transformer, including the winding resistance balancing structure.

[0047] The transformer adopts a winding resistance balance structure, which can reduce the resistance difference between the three phases and reduce the resistance unbalance rate.

[0048] Further, such as Figure 8 As shown, in one embodiment of the utility model, an iron core 10 is included, and an X-phase winding 1 , a Y-phase winding 2 and a Z-phase winding 3 are installed on the iron core 10 .

[0049] A corresponding coil is wound around each column of the iron core 10, and the bottom is connected by an iron yoke to form a closed magnetic circuit to ensure the complete flow of magnetic lines of force.

[0050] In summary, the utility model effectively overcomes various shortcomings of the prior art and has high industrial utilization value.

[0051] The above embodiments are merely illustrative of the principles and effects of the present invention, and are not intended to limit the present invention. Anyone familiar with the technology may modify or alter the above embodiments without departing from the spirit and scope of the present invention. Therefore, all equivalent modifications or alterations made by a person of ordinary skill in the art without departing from the spirit and technical concept disclosed in the present invention shall still be covered by the claims of the present invention.

Claims

1. A winding resistance balancing structure, characterized in that: include: An X-phase lead wire row and an X-phase outgoing wire row connected to the X-phase winding; A Y-phase lead wire row and a Y-phase outgoing wire row connected to the Y-phase winding; A Z-phase lead wire row and a Z-phase outgoing wire row connected to the Z-phase winding; First rear row; The second rear row; The first tail row connects the X-phase lead row, the Y-phase lead row and the Z-phase lead row, and the second tail row connects the X-phase lead row and the Z-phase lead row.

2. A winding resistance balancing structure according to claim 1, characterized in that: The first tail row and the second tail row are arranged side by side with an interval, the X-phase lead row is provided with an X-phase plane connection portion; the Y-phase lead row is provided with a Y-phase plane connection portion; and the Z-phase lead row is provided with a Z-phase plane connection portion; The X-phase plane connecting portion, the Y-phase plane connecting portion and the Z-phase plane connecting portion are simultaneously abutted against the first tail row and the second tail row; The Y-phase plane connecting portion is located between the X-phase plane connecting portion and the Z-phase plane connecting portion; An insulating member is provided in the area where the second tail row abuts against the Y-phase plane connecting portion, so that the second tail row is insulated and connected to the Y-phase plane connecting portion.

3. A winding resistance balancing structure according to claim 2, characterized in that: The insulating member is insulating paper.

4. The winding resistance balancing structure according to claim 1, characterized in that: The X-phase outgoing line row and the Z-phase outgoing line row are both connected with a transition row.

5. A winding resistance balancing structure according to claim 4, characterized in that: The transition bar and the Y-phase outgoing line bar are both connected with a copper bar soft connection.

6. A winding resistance balancing structure according to claim 5, characterized in that: The copper busbar is softly connected to the bushing.

7. A transformer, characterized in that: The invention comprises a winding resistance balancing structure as claimed in any one of claims 1 to 6.

8. A transformer according to claim 7, characterized in that: It comprises an iron core, and the X-phase winding, the Y-phase winding and the Z-phase winding are mounted on the iron core.

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