Voltage regulating end ring of high-voltage transformer

Abstract

The utility model belongs to the technical field of transformer assemblies, and particularly discloses a voltage regulating end ring of a high-voltage transformer, which comprises a plurality of layers of insulating paperboards, a plurality of limiting bandages and a plurality of layers of laminated wood positioning pins, a plurality of limiting bandages are arranged, and the plurality of limiting bandages are bound on the outer sides of the plurality of insulating paperboards; a plurality of positioning holes are uniformly formed in the insulating paper board, and the laminated wood positioning pin is inserted into each positioning hole; by drilling holes in the surface of the insulating paper board, the problem that partial discharge is easily generated due to the fact that moisture is contained in an adhesive layer is solved. Laminated wood positioning pins are inserted into insulating paperboard holes for fixing, the situation that the insulating paperboard is difficult to dry due to the fact that used glue contains moisture is avoided, and the fixing effect is good. The binding space is infinitely large by using the limiting binding band, so that the binding device is more adaptive to the curved-surface insulating paper board, and multiple layers of insulating paper boards can be bound.

Description

Technical Field

[0001] The utility model relates to the technical field of transformer components, in particular to a voltage regulating end ring of a high-voltage transformer. Background Art

[0002] With the continuous growth of the national economy, electricity consumption in various fields such as industry, commerce, and residents continues to increase. High-voltage transformer power transmission has the advantages of long distance, large capacity, and low loss. The high-voltage production capacity above 220kV is growing rapidly. For high-voltage transformers, the design structure and process methods of the voltage regulating end ring are particularly important.

[0003] The traditional structure of the existing transformer voltage regulating end ring: 220kV voltage regulating end ring is made of multi-layer insulation cardboard 1 cut into a certain shape, coated with PVA glue 2 and then formed into a ring (such as Figure 1 The manufacturing method involves pre-rolling a single sheet of insulating cardboard 1 into a shape. Using an open C-shaped clamp 3, multiple layers of the single sheets are clamped and compacted in equal parts, then placed in a drying oven for drying. After drying, PVA glue 2 is applied to the surface of the single sheets 1. The single sheets 1 are then stacked layer by layer to form a multi-layered structure, which is then cold-pressed.

[0004] However, the current transformer voltage regulating end ring has the following defects:

[0005] 1. The open C-type clamp has a limited structure and can only hold 5 pieces at a time, which is inefficient.

[0006] 2. The open C-shaped clamp 3 is open C-shaped. When clamping the insulating cardboard 1, it cannot better clamp the curved surface, and the fit is not very good. In particular, the middle part of the insulating cardboard cannot be well clamped, causing local deformation when the PVA glue 2 is tied.

[0007] 3. PVA glue 2 is a solvent. When applied manually, if the application is uneven or not in place, the adhesion of the insulating paperboard 1 will be affected.

[0008] 4. When applying artificial PVA glue 2, if the coating is uneven and PVA glue 2 is accumulated, the accumulated PVA glue 2 has too much glue. When the insulating cardboard 1 is drying, the moisture in the glue layer is not completely absorbed. For the high-voltage transformer voltage regulating end ring, which is often in a high electric field area, the moisture in the glue layer will cause partial discharge of the product, which is not allowed. Due to the long-term operation of the transformer, partial partial discharge will cause a safety hazard to the transformer. Once the partial discharge exceeds the standard, the economic loss will be immeasurable. Utility Model Content

[0009] The purpose of the present utility model is to provide a voltage regulating end ring of a high voltage transformer to solve the problems raised in the above background technology.

[0010] To achieve the above objectives, the present invention provides the following technical solution: a high-voltage transformer voltage regulating end ring, comprising an insulating cardboard, a retaining band, and a laminated wood locating pin. The insulating cardboard is circular and has several layers; a plurality of retaining bands are provided, each of which is tied to the outside of the insulating cardboard; and the insulating cardboard is uniformly provided with a plurality of positioning holes, each of which is inserted with a laminated wood locating pin. Drilling holes in the insulating cardboard surface accelerates drying, and the laminated wood locating pins are inserted into the holes to secure the insulating cardboard, eliminating the need for glue. The insulating cardboard can be adapted to circular insulating cardboard.

[0011] As a preferred embodiment of the present invention, the plurality of insulating paperboards are concentrically arranged, and each insulating paperboard is pre-circled using a rolling machine, and the inner diameter of the insulating paperboard is required to be close to the requirements of the drawing.

[0012] As a preferred embodiment of the present invention, the limiting strap is made of PET material to ensure that the limiting strap has a certain flexibility and that the limiting strap can shrink to 10% of its length at a temperature of 80°C.

[0013] As a preferred embodiment of the present invention, the plurality of limiting straps are distributed in a ring array to ensure that the insulating paperboard is evenly stressed.

[0014] As a preferred embodiment of the present invention, the diameter of the positioning hole is 8 cm, the diameter of the laminated wood positioning pin is 8.5 cm, and burrs need to be removed from the positioning hole.

[0015] As a preferred embodiment of the present invention, the positioning holes and the laminated wood positioning pins are interference fit so that each insulating paperboard is firmly locked together.

[0016] Compared with the prior art, the beneficial effects of the present invention are:

[0017] This utility model drills holes in the surface of the insulating cardboard to address the problem of moisture in the adhesive layer, which can easily cause partial discharge. Laminated wood dowel pins are inserted into the holes to secure the insulation, preventing moisture from entering the glue and hindering drying. This also improves the securing effect. The use of limited-space binding straps allows for unlimited binding space, making them more adaptable to curved surfaces. Multiple layers of insulation can be tied together, saving handling time and significantly improving drying efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 This is a schematic diagram of the structure of the voltage regulating end ring of an existing high voltage transformer;

[0019] Figure 2 This is a schematic diagram of the split structure of the existing high-voltage transformer voltage regulating end ring;

[0020] Figure 3 This is a schematic diagram of the three-dimensional structure of the utility model;

[0021] Figure 4 This is a schematic diagram of the unperforated structure of the insulating paperboard of the utility model;

[0022] Figure 5 This is a schematic diagram of the positioning hole structure of the utility model.

[0023] In the figure: 1. Insulation cardboard; 2. PVA glue; 3. Open C-shaped clamp; 4. Limiting strap; 5. Laminated wood locating pin. DETAILED DESCRIPTION

[0024] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the embodiments described are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0025] In the description of the present invention, it should be noted that the terms "vertical", "up", "down", "horizontal", etc. indicating orientations or positional relationships are based on the orientations or positional relationships shown in the accompanying drawings. They are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation. Therefore, they cannot be understood as limitations on the present invention.

[0026] It should also be noted that, in the description of this utility model, unless otherwise expressly specified or limited, the terms "disposed," "installed," "connected," and "connected" should be understood in a broad sense. For example, they may refer to fixed connections, detachable connections, or integral connections; they may refer to mechanical connections or electrical connections; they may refer to direct connections or indirect connections through an intermediate medium; and they may refer to internal communication between two components. Those skilled in the art will be able to understand the specific meanings of the above terms in this utility model based on specific circumstances.

[0027] See also Figure 3-5 The utility model provides a technical solution: a high-voltage transformer voltage regulating end ring includes an insulating cardboard 1, a limiting strap 4 and a laminated wood positioning pin 5. The insulating cardboard 1 is circular and has several layers; there are several limiting straps 4, and several limiting straps 4 are tied to the outside of several insulating cardboards 1; a plurality of positioning holes are evenly opened on the insulating cardboard 1, and the laminated wood positioning pin 5 is inserted into each positioning hole.

[0028] Drilling holes on the surface of the insulating cardboard 1 can accelerate the drying efficiency of the insulating cardboard 1, and using laminated wood positioning pins 5 to insert the holes of the insulating cardboard 1 for fixing, avoiding the use of glue, and using the insulating cardboard 1 can adapt to circular insulating cardboards 1.

[0029] The plurality of insulating paperboards 1 are concentrically arranged, and each insulating paperboard 1 is pre-circled using a rolling machine, and the inner diameter of the insulating paperboard 1 is required to be close to the requirements of the drawing.

[0030] The limiting strap 4 is made of PET material, which ensures that the limiting strap 4 has a certain flexibility and enables the limiting strap 4 to shrink to 10% of its length at a temperature of 80°C.

[0031] The plurality of limiting straps 4 are distributed in a ring array to ensure that the insulating paperboard 1 is evenly stressed.

[0032] The diameter of the positioning hole is 8 cm, and the diameter of the laminated wood positioning pin 5 is 8.5 cm. The positioning hole needs to be deburred.

[0033] The positioning holes are interference-fitted with the laminated wood positioning pins 5 so that each insulating paperboard 1 is firmly locked together.

[0034] In summary, the specific implementation methods of the present invention are as follows:

[0035] Cancel Figure 1 PVA glue 2 is used to bond the insulation paperboard 1 and cancel Figure 1 Middle opening C-type clamp 3.

[0036] Will Figure 1 The insulating cardboard 1 is moistened, and then the insulating cardboards 1 are pre-circled one by one using a rolling machine. The inner diameter of the insulating cardboard 1 is required to be close to the requirements of the drawing.

[0037] Stack the insulating cardboard sheets 1 one by one. Figure 2 Since there is no PVA glue 2 between each cardboard, it is necessary to use a limiting band 4 to fix and shape it into a circle. After the initial shaping, it is sent to the drying room. Due to the heat shrinkage of the insulation cardboard 1 fibers, it is finally dried and shaped.

[0038] After the dried and shaped insulating end ring has cooled, use an electric drill to drill a positioning hole with a diameter of 8 cm on its surface, and then remove the burrs at the drill hole (such as Figure 5 ).

[0039] In order to ensure that the transformer oil at the cardboard hole has good fluidity and permeability, a laminated wood positioning pin 5 is designed.

[0040] Drive the laminated wood dowel pins 5 with a diameter of 8.5 cm tightly into the holes drilled in the insulation end rings so that each of the insulation paperboards 1 is firmly locked together to form a whole (such as Figure 3 ).

[0041] Improve the design and process implementation advantages of high voltage transformer voltage regulating end ring

[0042] Mechanical fixation: The laminated wood positioning pins 5 can firmly fix the insulating paperboard 1 in a specific position to prevent the insulating paperboard 1 from loosening due to vibration, electromagnetic force and other factors during the operation of the transformer.

[0043] Resist external impact: When the transformer is subjected to external impact (such as the external force caused by coil short circuit), since the laminated wood positioning pin 5 is made of electrical laminated wood, it has a certain hardness. The laminated wood positioning pin 5 can help the insulating end ring to withstand part of the impact force and prevent the insulating end ring from loosening and deformation. If the insulating end ring of the high-voltage transformer is deformed, the coil will lose mechanical support, posing a safety hazard to the transformer.

[0044] Maintaining insulation performance: Laminated wood dowel pins 5 are typically made of high-quality insulating laminated wood, providing a good insulation fit with the insulating end ring. This ensures a more uniform electric field distribution around the insulating end ring, minimizing electric field concentration and helping to reduce local electric field strength, thereby extending the life of the transformer.

[0045] When the limiting band 4 is at a temperature of 80° C., the length of the limiting band 4 can be thermally shrunk to 10% of its heat shrinkage physical property, so that the layers of the insulating cardboard 1 are more firmly bound.

[0046] The limiting strap 4 binds the insulating cardboard 1 one by one. Figure 4 Because the limiting strap 4 has a certain degree of flexibility, it can follow the arc surface of the cardboard for binding, while being able to penetrate the entire binding surface and having a wide range of binding positions. Due to these functions, the pre-setting of the insulating end ring is closer to the drawing requirements, and the conformity of the curved surface is more conducive to the fixation of the laminated wood positioning pin 5, thereby improving the mechanical strength of the insulating end ring and enhancing the overall resistance to sudden short circuits of the transformer.

[0047] The end rings of high-voltage transformers are formed by bonding with PVA glue 2. Since the glue contains moisture, it causes partial discharge inside the transformer, resulting in rework of the product. The economic loss can be hundreds of thousands or even millions. After years of testing and demonstration, it is feasible and successful to use laminated wood positioning pins 5 instead of PVA glue 2 to bond the insulating end rings of high-voltage transformers. This not only ensures product quality and improves efficiency, but also reduces the cost of transformer production.

[0048] Although the embodiments of the present invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and variations may be made to these embodiments without departing from the principles and spirit of the present invention, and the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. High voltage transformer voltage regulating end ring, characterized by: It comprises an insulating cardboard (1), a limiting strap (4) and a laminated wood positioning pin (5); The insulating paperboard (1) is circular, and the insulating paperboard (1) is provided with several layers; A plurality of the limiting straps (4) are provided, and the plurality of limiting straps (4) are tied to the outside of a plurality of the insulating cardboards (1); a plurality of positioning holes are evenly opened on the insulating cardboard (1), and the laminated wood positioning pin (5) is inserted into each of the positioning holes.

2. The high voltage transformer voltage regulating end ring according to claim 1, characterized in that: The plurality of insulating paperboards (1) are concentrically arranged, and each insulating paperboard (1) is pre-circled using a rolling machine.

3. The high voltage transformer voltage regulating end ring according to claim 1, characterized in that: The limiting strap (4) is made of PET material.

4. The high voltage transformer voltage regulating end ring according to claim 1, characterized in that: The plurality of position-limiting straps (4) are distributed in a ring array.

5. The high voltage transformer voltage regulating end ring according to claim 1, characterized in that: The diameter of the positioning hole is 8 cm, and the diameter of the laminated wood positioning pin (5) is 8.5 cm.

6. The high voltage transformer voltage regulating end ring according to claim 1, characterized in that: The positioning hole and the laminated wood positioning pin (5) are interference fit.

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