Structure for improving insulation performance of end part of axial split coil

Abstract

The invention relates to the technical field of transformers, in particular to a structure for improving the insulation performance of the end of an axial split coil, which comprises a wire and an insulation paperboard arranged on the outer side surface of the wire, and a cushion block is arranged at the top of the insulation paperboard. A structure formed by the insulating cardboard and the cushion block is connected with the other group of the insulating cardboard and the cushion block in a longitudinal end-to-end mode, and a supporting strip is arranged at one end of the cushion block and located on the inner side diameter of a coil of the wire; according to the invention, the insulating cardboard wraps the three surfaces of the wire, the upper and lower surfaces of the insulating cardboard are bonded with the corresponding cushion blocks, and the slotted end parts of the corresponding cushion blocks are clamped into the clamping grooves of the supporting strips, so that the purposes of shortening the supporting strips, keeping away from the angle rings of the transformer body and preventing the insulation from being damaged are achieved, and the fault tolerance is increased; the reject ratio increased due to errors in manual and production manufacturing processes is reduced, the production difficulty is reduced, and the insulation performance is further improved.

Description

Technical Field

[0001] This invention relates to the field of transformer technology, and in particular to a structure for improving the end insulation performance of axially split coils. Background Technology

[0002] Power transformers are the main electrical equipment in the power grid, and the coil, as one of its main components, constitutes the circuit part of the transformer. It is directly connected to the external power grid and is the most important component of the transformer. It needs to meet requirements such as electrical strength, mechanical strength, and heat resistance. The reliability of transformer operation often depends on the structural design and manufacturing quality of the coil.

[0003] Axial splitting of the coil is a split winding structure symmetrically arranged along the axial direction of the transformer core column. Its core feature is splitting the low-voltage winding into two independent parts, upper and lower. Axial splitting coils are complex in structure, difficult to design and manufacture, and difficult to modify after winding. Therefore, a 2-4mm wide slot needs to be cut into the upper part of the inner support bar of the lower coil to facilitate manual shortening of the support bar after coil compression. Due to errors in manual operation and manufacturing processes, the inner corner ring of the transformer body at the upper end of the coil is easily lifted, deformed, or damaged by the inner support bar, causing insulation damage and creepage.

[0004] Therefore, to address the above issues, a structure can be designed to improve the insulation performance of the axial split coil ends. This involves thinning the ends of the support bars, creating a "step," and adding insulating cardboard at the coil wrapping point to achieve inner diameter side support. This achieves the goals of shortening the support bars, moving them away from the coil body corner rings, and preventing insulation damage. Summary of the Invention

[0005] In order to overcome the problem that the inner corner ring at the upper end of the coil is easily lifted, deformed, or damaged by the inner support bar, causing insulation damage and resulting in creepage.

[0006] The technical solution of the present invention is as follows: a structure for improving the insulation performance of the end of an axial split coil, comprising a conductor and an insulating paperboard disposed on the outer surface of the conductor, a pad being disposed on the top of the insulating paperboard, the structure consisting of the insulating paperboard and the pad being connected end to end to another set of longitudinal sections, a support strip being disposed at one end of the pad being located on the inner diameter of the coil of the conductor.

[0007] Preferably, the insulating paperboard is wrapped around three sides of the conductor, and the top and bottom sides of the insulating paperboard are bonded to the corresponding pads. The slotted end of the corresponding pad is inserted into the slot of the support bar. This achieves the purpose of shortening the support bar, moving it away from the corner ring of the transformer body, and preventing damage to the insulation. It also increases the tolerance for errors, reduces the defect rate caused by human error and manufacturing process, reduces the difficulty of production, and further improves the insulation performance.

[0008] Preferably, the insulating paperboard is a long strip bent into a "U" shape, and the three sides of the bent insulating paperboard are respectively attached to the upper end face, lower end face and inner diameter face of the conductor.

[0009] Preferably, the pad has a rectangular structure, and grooves are provided on the two short sides of the pad.

[0010] Preferably, the support bar has a stepped groove on the side near the pad, the groove of the support bar and the groove of the pad are adapted to each other and engage, and a break groove is formed at the top of the support bar groove.

[0011] The beneficial effects of this invention are: The rectangular insulating paperboard is bent into a U-shape along its length to wrap around the top, bottom, and inner diameter sides of the wire coil at the end of the conductor winding. The insulating paperboard is firmly bonded to the adjacent pads, and the insulating paperboard must not exceed the outer limit of the conductor's outer diameter side. The support strip should be in contact with the insulating paperboard to provide radial support. By thinning the end of the support strip, creating a groove, and adding insulating paperboard at the coil end, inner diameter side support is achieved. This achieves the purpose of shortening the support strip, moving it away from the corner ring of the transformer body, and preventing damage to the insulation. It also increases tolerance for errors, reduces the defect rate caused by human error and manufacturing process, reduces production difficulty, and further improves insulation performance. Attached Figure Description

[0012] Figure 1 The diagram shown is a three-dimensional schematic of the structure of the present invention for improving the insulation performance of the ends of an axially split coil; Figure 2 The diagram shown is a three-dimensional schematic of the structural insulating paperboard for improving the insulation performance of the ends of axially split coils according to the present invention. Figure 3 The diagram shown is a three-dimensional schematic of the structural pad block of the present invention for improving the insulation performance of the ends of axial split coils; Figure 4 The diagram shown is a three-dimensional schematic of the structural support bar of the present invention for improving the insulation performance of the ends of axially split coils.

[0013] Explanation of reference numerals in the attached diagram: 1. Wire; 2. Insulating cardboard; 3. Pad; 4. Support bar. Detailed Implementation

[0014] The present invention will be further described below with reference to the accompanying drawings and embodiments.

[0015] Example 1

[0016] This application can actually solve the problem that the inner corner ring of the coil body at the upper end is easily pushed up, deformed, and damaged by the inner support bar, causing insulation damage and resulting in creepage. In this embodiment, according to Figure 1 , Figure 2, Figure 3 and Figure 4 As shown, it includes a wire 1 and an insulating paperboard 2 disposed on the outer surface of the wire 1. A pad 3 is disposed on the top of the insulating paperboard 2. The structure formed by the insulating paperboard 2 and the pad 3 is connected to another set of longitudinal ends. A support bar 4 is disposed at one end of the pad 3. The support bar 4 is located on the inner diameter of the coil of the wire 1.

[0017] The insulating paperboard 2 is wrapped around three sides of the conductor 1. The top and bottom sides of the insulating paperboard 2 are bonded to the corresponding pads 3. The slotted end of the corresponding pad 3 is inserted into the slot of the support bar 4. This achieves the purpose of shortening the support bar 4, moving it away from the corner ring of the device body, and preventing damage to the insulation. It also increases the tolerance for errors, reduces the defect rate caused by human error and manufacturing process, reduces production difficulty, and further improves the insulation performance.

[0018] Furthermore, the insulating paperboard 2 is a long strip bent into a "U" shape. The insulating paperboard is rectangular, with material code JBT4-0.5, a thickness of 0.5mm, a width of 25mm, and a length equal to (conductor height + conductor width × 2)mm. The length is rounded down appropriately to prevent the insulating paperboard from being too long and exceeding the outer limit of the conductor, which would prevent the installation of the inner coil outer support strip. The three bent sides of the insulating paperboard 2 are respectively attached to the upper end face, lower end face, and inner diameter face of the conductor 1 to ensure insulation. The cardboard 2 is bonded to the adjacent pad 3 to ensure that the insulating cardboard 2 will not move or fall off, and the insulating cardboard 2 shall not exceed the outer limit of the outer diameter of the conductor 1. The pad 3 has a rectangular structure, and grooves are provided on the two short sides of the pad 3. The support bar 4 has a stepped slot on the side near the pad 3. The slot of the support bar 4 and the groove of the pad 3 are adapted to each other and engage. A break-off groove is provided at the top of the slot of the support bar 4. The break-off groove is designed to facilitate manual break-off after the coil is assembled.

[0019] Working principle: When winding the inner coil, a specially designed inner coil support bar 4 is used. The support bar 4 is placed close to the conductor 1 on the slot side. When winding the end of the coil, a newly designed pad 3 is used. The rectangular insulating paperboard 2 is bent into a U-shape along its length to wrap the upper, lower and inner diameter sides of the winding end of the conductor 1. The insulating paperboard 2 is firmly bonded to the adjacent pad 3, and the insulating paperboard 2 should not exceed the outer limit of the outer diameter side of the conductor 1. The support bar 4 should be in contact with the insulating paperboard 2 to provide radial support. The slot on the support bar 4 should match the groove of the insulating paperboard 2 to meet the requirements of the oil gap width on the inner diameter side of the coil.

[0020] The embodiments of the present invention have been described in detail above with reference to the accompanying drawings. However, the present invention 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 invention.

Claims

1. A structure for improving the performance of the end insulation of an axially split coil comprising a conductor wire (1), characterized in that: The utility model also includes the insulating paper board (2) of setting in the outer side surface of wire (1), the top of insulating paper board (2) is provided with the cushion block (3), the structure of insulating paper board (2) and the cushion block (3) constitutes the other group of longitudinal head-to-tail connection, one end of cushion block (3) is provided with the bracing piece (4), and the bracing piece (4) is located the inside diameter of wire (1) coil.

2. A structure for improving the end turn insulation performance of an axially split coil according to claim 1, characterized in that: The insulating paper board (2) is long strip shape and is bent into "U" shape structure, and the three surfaces of the insulating paper board (2) are respectively attached to the upper end surface, the lower end surface and the inside diameter surface of the wire (1).

3. A structure for improving the end turn insulation performance of an axially split coil according to claim 1, characterized in that: The cushion block (3) is rectangular structure, and recesses are formed in the positions of two short sides of the cushion block (3).

4. A structure for improving the end turn insulation performance of an axially split coil according to claim 3, characterized in that: The bracing piece (4) is provided with a stepped clamping groove on the side close to the cushion block (3), the clamping groove of the bracing piece (4) and the recess of the cushion block (3) are matched and clamped with each other, and a breaking groove is formed in the top of the clamping groove of the bracing piece (4).

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