Transformer winding anti-short-circuit pressing structure

Abstract

The invention provides a transformer winding anti-short-circuit pressing structure which comprises hard plastic pressing rings located at the upper end and the lower end of a winding, the outer sides of the pressing rings and the winding are sleeved with a composite supporting shell, and the pressing rings are connected with the composite supporting shell. According to the invention, the hold-down ring made of a hard plastic material is arranged to effectively replace a traditional paperboard for hold-down, so that the weight of the transformer is effectively reduced while an excellent insulation effect is realized, the production cost is reduced, the short-circuit tolerance performance is greatly enhanced, and the hold-down effect is improved.

Description

Technical Field

[0001] The present invention relates to the technical field of transformers, and in particular to a short-circuit resistant pressing structure for transformer windings. Background Art

[0002] In modern power systems, transformers, as key equipment, undertake important tasks such as voltage transformation, power transmission, and distribution. The transformer winding refers to the circuit part of the transformer, which is wound by copper wires or aluminum wires with high electrical conductivity and is applied to power systems. The winding should have sufficient insulation strength, mechanical strength, and heat resistance.

[0003] However, transformers face severe challenges of short-circuit faults during operation. When a short circuit occurs, a powerful short-circuit current will be generated instantaneously, and a huge electrodynamic force will act on the transformer winding.

[0004] At present, the common cardboard pressing structure for transformer windings has many defects. In the face of short-circuit electrodynamic force, it lacks sufficient buffering and self-adaptive capabilities, cannot effectively disperse and absorb the electrodynamic force, and is prone to local stress concentration in the winding, which may cause the pressing cardboard to be damaged and the insulation to be damaged. The pressing force will gradually relax, making the winding unable to obtain reliable fastening support during short circuit, greatly increasing the risk of transformer failure. Such problems not only affect the normal operation of the transformer, shorten its service life, but also may trigger large-scale power outages in the power system, bringing serious economic losses to social production and life. Summary of the Invention

[0005] The purpose of the present invention is to provide a short-circuit resistant pressing structure for transformer windings to solve the above technical problems.

[0006] The present invention provides a short-circuit resistant pressing structure for transformer windings, including hard plastic pressing rings located at the upper and lower ends of the winding. A composite support shell is sleeved outside the pressing rings and the winding, and the pressing rings are connected to the composite support shell.

[0007] Further, the pressing ring is a ring-shaped structure with an opening.

[0008] Further, the size of one end face of the pressing ring is larger than that of the other end face.

[0009] Further, the pressing ring is sleeved on the iron core.

[0010] Further, clamping members are provided on the iron core, and a pressing assembly is provided between the clamping members and the pressing ring.

[0011] Furthermore, the composite support housing includes an elastic buffer layer and a rigid support layer. The elastic buffer layer is wrapped around the outside of the winding, and the rigid support layer is arranged on the outside of the pressing ring and the elastic buffer layer.

[0012] Furthermore, the pressing ring and the rigid support layer are bonded by epoxy resin glue.

[0013] Furthermore, an insulating layer is wrapped around the outside of the composite support housing.

[0014] Furthermore, the insulating layer is made of paper material.

[0015] By providing a pressing ring made of hard plastic material, the present invention effectively replaces the traditional pressing cardboard. While achieving excellent insulation effects, it effectively reduces the weight of the transformer, lowers the production cost, greatly enhances the short-circuit withstand performance, and improves the pressing effect. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] In order to more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the following will briefly introduce the drawings required for the description of the specific embodiments or the prior art. Obviously, the drawings in the following description are some embodiments of the present invention. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative efforts.

[0017] Figure 1 It is the main structure diagram of the transformer core and winding of the present invention;

[0018] Figure 2 It is the schematic diagram of the structure of the pressing ring of the present invention;

[0019] Figure 3 It is the installation schematic diagram of the pressing assembly in Embodiment 1 of the present invention;

[0020] Figure 4 It is the installation schematic diagram of the pressing assembly in Embodiment 2 of the present invention;

[0021] Figure 5 It is the structure diagram of the pressing assembly in Embodiment 2 of the present invention

[0022] Figure 6 It is of the present invention Figure 4 The partial enlarged view at A in;

[0023] Explanation of the reference numerals:

[0024] In the figure: 1 - iron core, 2 - pressing ring, 3 - elastic buffer layer, 4 - rigid support layer, 5 - insulating layer, 6 - clamping piece, 7 - pressing plate, 8 - bolt, 9 - adjusting nut, 10 - locking nut, 11 - clamping groove, 12 - support ring, 13 - hinge seat, 14 - limiting rod, 15 - limiting groove; Specific embodiments

[0025] The technical solutions of the present invention will be clearly and completely described below in conjunction with the embodiments. Obviously, the described embodiments are some of the embodiments of the present invention, rather than all of them. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0026] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "transverse", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", etc. indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and thus cannot be understood as a limitation of the present invention.

[0027] In addition, the terms "first" and "second" are only used for descriptive purposes and cannot be understood as indicating or implying relative importance or implicitly indicating the quantity of the indicated technical features. Thus, the features defined with "first" and "second" may explicitly or implicitly include one or more of the described features. In the description of the present invention, "a plurality" means two or more unless otherwise specifically defined. In addition, the terms "installation", "connection", and "connection" should be understood in a broad sense. For example, it may be a fixed connection, a detachable connection, or an integral connection; it may be a mechanical connection or an electrical connection; it may be directly connected or indirectly connected through an intermediate medium, and it may be the communication inside two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0028] Embodiment 1

[0029] As Figures 1 - 3 shown:

[0030] A short - circuit resistant pressing structure for a transformer winding includes hard plastic pressing rings 2 located at the upper and lower ends of the winding. In this embodiment, the transformer is a conventional transformer, which has an iron core 1, a winding helically wound around the iron core 1, and a clamping piece 6 installed on the iron core 1.

[0031] The pressing ring 2 is sleeved on the iron core 1.

[0032] The pressing ring 2 is an annular structure with an opening, and the size of one end face of the pressing ring 2 is larger than that of the other end face.

[0033] A composite support housing is sleeved on the outside of the pressing ring 2 and the winding, and the pressing ring 2 is connected to the composite support housing.

[0034] The composite support housing includes an elastic buffer layer 3 and a rigid support layer 4. The elastic buffer layer 3 is coated on the outside of the winding, and the rigid support layer 4 is arranged on the outside of the pressing ring 2 and the elastic buffer layer 3.

[0035] The pressing ring 2 is bonded to the rigid support layer 4 by epoxy resin glue.

[0036] An insulating layer 5 is coated on the outside of the composite support housing, and the insulating layer 5 is made of paper material.

[0037] A clamping piece 6 is arranged on the iron core 1, and a pressing assembly is arranged between the clamping piece 6 and the pressing ring 2.

[0038] As Figure 3 shown, the pressing assembly includes a pressing plate 7 closely attached to the surface of the pressing ring 2. A bolt 8 is arranged at the top of the pressing plate 7. A threaded hole corresponding to the bolt 8 is opened on the clamping piece 6. The bolt 8 is threadedly connected to the threaded hole. An adjusting nut 9 located below the threaded hole and a locking nut 10 located above the threaded hole are threadedly connected to the bolt 8.

[0039] The bolt 8 is fastened to the clamping piece 6 through the cooperation of the adjusting nut 9 and the locking nut 10, and the position of the bolt 8 is adjusted by adjusting their positions on the bolt 8, and then the height of the pressing plate 7 is adjusted.

[0040] Embodiment 2

[0041] As Figures 4 - 6 shown, the difference between this embodiment and Embodiment 1 is that a circular clamping groove 11 is opened on the top surface of the pressing plate 7. The bottom of the bolt 8 is installed on the bottom surface of the clamping groove 11. A support ring 12 coaxially arranged with the bolt 8 is slidably sleeved on the bolt 8, and the outer diameter of the support ring 12 is not greater than the inner diameter of the clamping groove 11.

[0042] A plurality of hinge seats 13 are uniformly arranged on the outer side wall of the support ring 12. A limiting rod 14 is hingedly connected to the hinge seat 13, and the limiting rod 14 is hinged to the hinge seat 13 through a rotating shaft.

[0043] A snap spring is arranged between the rotating shaft and the hinge seat 13. The limiting rod 14 is always subjected to a force towards the direction close to the bolt 8 under the drive of the snap spring, ensuring that the top end of the limiting rod 14 always contacts and is slidably connected to the bottom surface of the clamping piece 6.

[0044] A limiting groove 15 corresponding to the limiting rod 14 is arranged on the bottom surface of the clamping piece 6.

[0045] When the transformer winding wants to move under the short-circuit electrodynamic force, the transformer winding will push the pressing ring 2 to move outward. In the state of the threaded connection between the bolt 8 and the adjusting nut 9, the locking nut 10 and the threaded hole, at this time, the pressing plate 7 provides stable support for the pressing ring 2.

[0046] When the force of the transformer winding pushing the pressing ring 2 is relatively large and the threaded connection state between the bolt 8 and the adjusting nut 9, the locking nut 10 and the threaded hole is not enough to resist the thrust of the transformer winding, the thread will be damaged and the blocking force and biting force between the threads will fail. At this time, the pressing plate 7 receives the upward or downward thrust of the pressing ring 2, and the pressing plate 7 moves slightly upward. The supporting ring 12 cooperates with the clamping groove 11 on the top surface of the pressing plate 7, the supporting ring 12 falls into the clamping groove 11, the pressing plate 7 will push the supporting ring 12 to move upward, the supporting ring 12 pushes the limiting rod 14 to slide outward until the limiting rod 14 is stuck in the limiting groove 15, the movement of the limiting rod 14 is restricted, and then the supporting ring 12 and the pressing plate 7 cannot move, and the pressing plate 7 presses the pressing ring 2 to prevent the transformer winding from further displacement.

[0047] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that they can still modify the technical solutions described in the foregoing embodiments, or perform equivalent replacements on some or all of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A transformer winding anti-short circuit compression structure, characterized in that It comprises hard plastic clamping rings located at the upper and lower ends of the winding, the outer sides of the clamping ring and the winding are sleeved with a composite support shell, and the clamping ring is connected to the composite support shell.

2. The transformer winding anti-short circuit compression structure according to claim 1, characterized in that: The clamping ring is a ring-shaped structure with an opening.

3. The transformer winding anti-short circuit compression structure according to claim 2, characterized in that: The dimension of one end surface of the clamping ring is larger than the dimension of the other end surface.

4. The transformer winding anti-short circuit compression structure according to claim 1, characterized in that: The clamping ring is sleeved on the iron core.

5. The transformer winding anti-short circuit compression structure according to claim 4, characterized in that: A clamp is arranged on the iron core, and a clamping assembly is arranged between the clamp and the clamping ring.

6. The transformer winding anti-short circuit compression structure according to claim 1, characterized in that: The composite support shell comprises an elastic buffer layer and a rigid support layer. The elastic buffer layer is coated on the outside of the winding, and the rigid support layer is arranged on the outside of the clamping ring and the elastic buffer layer.

7. The transformer winding anti-short circuit compression structure according to claim 6, characterized in that: The clamping ring is bonded to the rigid supporting layer by epoxy resin glue.

8. The transformer winding anti-short circuit compression structure according to claim 1, characterized in that: The outer side of the composite supporting shell is covered with an insulating layer.

9. The transformer winding anti-short circuit compression structure according to claim 8, characterized in that: The insulating layer is made of paper material.

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