阅读说明：本技术 一种干式变压器箔式线圈绕制方法及干式变压器箔式线圈 (Dry-type transformer foil coil winding method and dry-type transformer foil coil ) 是由 张军海 张绮雯 叶彪 莫向松 郭敬旺 彭景伟 余小平 廖冬虹 李太山 黄伟峰 于 2021-06-07 设计创作，主要内容包括：本发明公开了一种干式变压器箔式线圈绕制方法及干式变压器箔式线圈,所述方法包括：获取模具,在模具上绕制多层铜箔,得到铜箔线圈；在绕制多层铜箔的过程中,在每个相邻两层铜箔之间安装至少一气道板；对所述铜箔线圈进行加热固化,并对所述铜箔线圈的端部进行绝缘处理；将绝缘处理后的铜箔线圈与所述模具平放,取出模具,得到干式变压器的低压线圈。本发明通过在每相邻两层铜箔之间安装至少一气道板,利用所述气道板作为成型绕组轴向散热气道的模板,可实现对低压线圈的散热,避免仅通过中空的撑条进行散热时,只能对与撑条相邻的几层线圈进行散热的问题。(The invention discloses a dry-type transformer foil coil winding method and a dry-type transformer foil coil, wherein the method comprises the following steps: obtaining a die, and winding a plurality of layers of copper foils on the die to obtain a copper foil coil; in the process of winding the multiple layers of copper foils, at least one air duct plate is arranged between every two adjacent layers of copper foils; heating and curing the copper foil coil, and carrying out insulation treatment on the end part of the copper foil coil; and flatly placing the copper foil coil subjected to the insulation treatment with the mold, and taking out the mold to obtain the low-voltage coil of the dry-type transformer. According to the invention, at least one air channel plate is arranged between every two adjacent layers of copper foils, and the air channel plate is used as a template for forming the axial heat dissipation air channel of the winding, so that the heat dissipation of the low-voltage coil can be realized, and the problem that only a few layers of coils adjacent to the supporting strips can be subjected to heat dissipation when heat dissipation is carried out only through the hollow supporting strips is solved.)

1. A dry-type transformer foil coil winding method is characterized by comprising the following steps:

obtaining a die, and winding a plurality of layers of copper foils on the die to obtain a copper foil coil; in the process of winding the multiple layers of copper foils, at least one air duct plate is arranged between every two adjacent layers of copper foils;

heating and curing the copper foil coil, and carrying out insulation treatment on the end part of the copper foil coil;

and flatly placing the copper foil coil subjected to the insulation treatment with the mold, and taking out the mold to obtain the low-voltage coil of the dry-type transformer.

2. The method for winding the foil coil of the dry-type transformer according to claim 1, wherein the step of insulating the end of the copper foil coil comprises the steps of:

and carrying out epoxy resin encapsulation treatment on the end part of the copper foil coil.

3. A method for winding a foil coil of a dry-type transformer as claimed in claim 1, wherein the air duct plate comprises a hollow conical cylinder, an upper end plate is provided at an upper end of the hollow conical cylinder, a lower end plate is provided at a lower end of the hollow conical cylinder, and the hollow conical cylinder, the upper end plate and the lower end plate form a closed space.

4. A method for winding a foil coil for a dry-type transformer as claimed in claim 1, wherein the step of winding a plurality of layers of copper foil on a die comprises:

and sleeving a low-voltage insulating cylinder on the mold, and winding a plurality of layers of copper foils on the mold sleeved with the low-voltage insulating cylinder through a foil winding machine.

5. A dry transformer foil coil winding method as claimed in claim 1, wherein the low voltage insulation cylinder is made of nomic paper.

6. A method for winding a foil coil for a dry-type transformer as claimed in claim 1, further comprising: when a plurality of layers of copper foils are wound, a reinforcing layer is arranged between at least two adjacent layers of copper foils in the last layers of windings of the copper foil coil, and then the copper foils are continuously wound until the required number of layers of the low-voltage coil is reached.

7. The method for winding the foil coil of the dry-type transformer as claimed in claim 6, wherein the reinforcing layer is a steel plate, an epoxy resin plate or a glass fiber reinforced plastic plate.

8. A dry-type transformer foil coil winding method as claimed in claim 6, wherein the number of the last few layers of the copper foil coil is in the range of 2 to 5.

9. The method for winding a foil coil of a dry-type transformer according to claim 1, wherein the step of obtaining a low-voltage coil of a dry-type transformer further comprises: trimming the copper foil coil, wherein the trimming method comprises the following steps: and polishing the upper end surface and the lower end surface of the copper foil coil to enable the upper end surface and the lower end surface to be flat.

10. A dry-type transformer foil coil, characterized in that it is produced by the method according to any one of claims 1 to 9.

Technical Field

The invention relates to the technical field of transformers, in particular to a dry-type transformer foil coil winding method and a dry-type transformer foil coil.

Background

The current of the low-voltage coil of the dry-type transformer is usually large, if the low-voltage coil is manufactured by adopting wire winding, a plurality of low-voltage coils are required to be connected in parallel, and if a layer winding method is adopted during winding, a large spiral angle is generated, and when the transformer is short-circuited, a large mechanical force is generated in the vertical direction of the coil, so that the coil is damaged. The ends of the copper or aluminum foil are flat, and the axial force of the copper or aluminum foil during short circuit is only a fraction of the wire-wound structure, so that foil type windings are generally adopted in the low-voltage coil of the dry-type transformer.

The transformer coil is one of the most important parts in the transformer structure and is the component which generates the most heat in use, so the heat dissipation degree of the coil is directly related to the continuous use time of the transformer. In the traditional method for winding the low-voltage coil of the dry-type transformer, a circle of hollow supporting bars are mainly laid in the coil for air circulation heat dissipation, the heat dissipation mode can only dissipate a plurality of layers of coils adjacent to the supporting bars without considering the outermost or innermost coil, and if a plurality of supporting bars deform to block an air passage due to local stress of the transformer, the temperature of a certain part/position of the coil can rise rapidly, so that the continuous service life of the whole transformer is influenced, a fire disaster is even caused more seriously, and therefore how to dissipate heat of the low-voltage coil is very important.

Disclosure of Invention

In view of the above technical problems, an object of the present invention is to provide a dry type transformer foil winding method and a dry type transformer foil winding, which can solve the problem that only several layers of coils adjacent to a hollow stay can be cooled when the heat is radiated through the stay.

The invention adopts the following technical scheme:

a dry-type transformer foil coil winding method comprises the following steps:

obtaining a die, and winding a plurality of layers of copper foils on the die to obtain a copper foil coil; in the process of winding the multilayer copper foils, at least one air duct plate is arranged between every two adjacent layers of copper foils;

heating and curing the copper foil coil, and carrying out insulation treatment on the end part of the copper foil coil;

and flatly placing the copper foil coil subjected to the insulation treatment with the mold, and taking out the mold to obtain the low-voltage coil of the dry-type transformer.

Optionally, the insulating treatment of the end of the copper foil coil includes:

and carrying out epoxy resin encapsulation treatment on the end part of the copper foil coil.

Optionally, the air duct plate includes a hollow conical cylinder, an upper end plate is disposed at an upper end of the hollow conical cylinder, a lower end plate is disposed at a lower end of the hollow conical cylinder, and the hollow conical cylinder, the upper end plate and the lower end plate form a closed space.

Optionally, the winding the multilayer copper foil on the die includes:

and sleeving a low-voltage insulating cylinder on the mold, and winding a plurality of layers of copper foils on the mold sleeved with the low-voltage insulating cylinder through a foil winding machine.

Optionally, the low voltage insulation cylinder is made of nomick paper.

Optionally, the method further includes: when a plurality of layers of copper foils are wound, a reinforcing layer is arranged between at least two adjacent layers of copper foils in the last layers of windings of the copper foil coil, and then the copper foils are continuously wound until the required number of layers of the low-voltage coil is reached.

Optionally, the reinforcing layer is a steel plate, an epoxy resin plate or a glass fiber reinforced plastic plate.

Optionally, the number of the last few layers of windings of the copper foil coil ranges from 2 to 5.

Optionally, the step of obtaining the low-voltage coil of the dry-type transformer further includes: trimming the copper foil coil, wherein the trimming method comprises the following steps: and polishing the upper end surface and the lower end surface of the copper foil coil to enable the upper end surface and the lower end surface to be flat.

A dry-type transformer foil coil is prepared by the method.

Compared with the prior art, the invention has the beneficial effects that:

according to the invention, at least one air channel plate is arranged between every two adjacent layers of copper foils, and the air channel plate is used as a template for forming the axial heat dissipation air channel of the winding, so that the heat dissipation of the low-voltage coil can be realized, and the problem that only a few layers of coils adjacent to the stay can be subjected to heat dissipation when heat dissipation is performed through the hollow stay is solved.

Drawings

Fig. 1 is a schematic flow chart illustrating a method for winding a foil coil of a dry-type transformer according to an embodiment of the present invention;

fig. 2 is a schematic structural diagram of an air duct plate in a dry-type transformer foil coil winding method according to an embodiment of the present invention.

Detailed Description

The present invention will be further described with reference to the accompanying drawings and specific embodiments, and it should be noted that, in the premise of no conflict, the following described embodiments or technical features may be arbitrarily combined to form a new embodiment:

the first embodiment is as follows:

referring to fig. 1-2, fig. 1 shows a method for winding a foil coil of a dry-type transformer according to the present invention, which includes:

step S1, obtaining a die, and winding a plurality of layers of copper foils on the die to obtain a copper foil coil; in the process of winding the multilayer copper foils, at least one air duct plate is arranged between every two adjacent layers of copper foils;

wherein, mountable one or more air flue board between every adjacent two-layer copper foil, when a plurality of air flue boards of installation, the air flue on the air flue board can be for the alternating expression distributes, when avoiding certain air flue to block up, and the air flue on another air flue board also can dispel the heat to this position, and is rational in infrastructure, and the radiating effect is good.

Optionally, the winding the multilayer copper foil on the die includes:

and sleeving a low-voltage insulating cylinder on the mold, and winding a plurality of layers of copper foils on the mold sleeved with the low-voltage insulating cylinder through a foil winding machine.

As an embodiment, the die may include two semicircular cylinders and two positioning plates, the two ends of the two semicircular cylinders are respectively provided with the positioning plates, the two semicircular cylinders are fixedly connected by the positioning plates, the two semicircular cylinders are oppositely arranged, a gap is left between the two semicircular cylinders, and the die may be assembled on a foil winding machine.

It should be noted that, the foil winding is formed by winding a thin and wide conductor lamination, each layer has 1 turn, the interlayer insulation is the turn-to-turn insulation at the same time, and the foil winding generally adopts an axial air passage: and during winding, the air duct plate is wound together at the corresponding turn number position and then taken out to form an axial air duct.

Optionally, the low voltage insulation cylinder is made of nomick paper.

Through setting up the low pressure insulating cylinder, play the effect of isolated low pressure coil and mould.

By way of example, the reinforcement layer may be a steel plate, an epoxy plate or a glass fiber reinforced plastic plate.

Specifically, as shown in fig. 2, the air channel plate includes a hollow conical cylinder 1, an upper end plate 2 is disposed at an upper end of the hollow conical cylinder, a lower end plate 3 is disposed at a lower end of the hollow conical cylinder, and the hollow conical cylinder 1, the upper end plate 2 and the lower end plate 3 form a closed space.

The air duct plate is used as a template for forming the axial heat dissipation air duct of the winding.

The hollow conical cylinder 1 can be formed by rolling through a plate rolling machine, the upper end plate 2 and the lower end plate 3 can be machined and formed through a lathe, the machining mode is simple, and the cost is low. For example, the airway plate of one winding can be processed by only 800g of steel.

In the implementation process, the air channel plate is used as a template for forming the axial heat dissipation air channel of the winding, and compared with a polyformaldehyde POM air channel plate, the cost can be reduced, and the manufacturing period is shortened.

Step S2, heating and curing the copper foil coil, and insulating the end part of the copper foil coil;

as a specific example, the heat curing method may include the steps of:

sending the copper foil coil into an oven, keeping the temperature of the oven at 80 ℃, and preserving the heat for 4-6 hours;

gradually raising the temperature of the oven from 80 ℃ to 100 ℃ for 4 hours;

keeping the temperature of the oven at 100 ℃ and preserving the heat for 4 hours;

gradually raising the temperature of the oven from 100 ℃ to 130 ℃, wherein the temperature raising time is 0.5 hour;

keeping the temperature of the oven at 130 ℃, and keeping the temperature for 8-10 hours;

and naturally cooling the oven to 70 ℃, and moving the copper foil coil out of the oven.

And step S3, horizontally placing the copper foil coil after the insulation treatment with the mould, and taking out the mould to obtain the low-voltage coil of the dry-type transformer.

Optionally, the insulating treatment of the end of the copper foil coil includes:

and carrying out epoxy resin encapsulation treatment on the end part of the copper foil coil.

In the implementation process, at least one air channel plate is arranged between every two adjacent layers of copper foils and used as a template of the axial heat dissipation air channel of the forming winding, so that the heat dissipation of the low-voltage coil can be realized, and the problem that only several layers of coils adjacent to the stay can be subjected to heat dissipation when the heat dissipation is carried out through the hollow stay is solved.

Optionally, the method of the present invention further comprises:

when a plurality of layers of copper foils are wound, a reinforcing layer is arranged between at least two adjacent layers of copper foils in the last layers of windings of the copper foil coil, and then the copper foils are continuously wound until the required number of layers of the low-voltage coil is reached.

In a preferred embodiment, the number of the last windings of the copper foil coil ranges from 2 to 5.

For example, when the required number of layers of the low-voltage coil is 10, the last few layers of windings of the copper foil coil may be the last 2 layers, the last 3 layers, the last 4 layers and the last 5 layers, wherein the last 5 layers are the 6 th layer to the 10 th layer of the low-voltage coil, and the last 2 layers are the 9 th layer to the 10 th layer of the low-voltage coil. Specifically, when the winding operation is performed to the last 5 layers of windings of the low-voltage coil, a reinforcing layer is arranged between the last 5 th layer and the last 4 th layer of the low-voltage coil, a reinforcing layer can also be arranged between the last 4 th layer and the last 3 rd layer, a reinforcing layer is arranged between the last 3 rd layer and the last 2 nd layer, or a reinforcing layer is arranged between the last 1 st layer and the last 2 nd layer, and the reinforcing layer is selected to be an epoxy resin plate.

In the implementation process, the reinforcing layer is arranged, so that the deformation problem of the transformer coil caused by different tightness during winding is avoided, and the overall stability of the transformer coil is improved.

Optionally, the step of obtaining the low-voltage coil of the dry-type transformer further includes:

and step S4, trimming the low-voltage coil, wherein the trimming method comprises the following steps: and polishing the upper end surface and the lower end surface of the copper foil coil to enable the upper end surface and the lower end surface to be flat.

Example two:

as an example, the foil coil of the dry-type transformer of the present invention may be prepared by the following method:

obtaining a die, and winding a plurality of layers of copper foils on the die to obtain a copper foil coil; in the process of winding the multilayer copper foils, at least one air duct plate is arranged between every two adjacent layers of copper foils;

heating and curing the copper foil coil, and carrying out insulation treatment on the end part of the copper foil coil;

and flatly placing the copper foil coil subjected to the insulation treatment with the mold, and taking out the mold to obtain the low-voltage coil of the dry-type transformer.

Trimming the low voltage coil, the trimming method comprising: and polishing the upper end surface and the lower end surface of the copper foil coil to enable the upper end surface and the lower end surface to be flat.

In the implementation process, the dry-type transformer foil coil is provided with at least one air channel plate between every two adjacent layers of copper foils, the air channel plate is used as a template for forming the axial heat dissipation air channel of the winding, the heat dissipation of the low-voltage coil can be realized, and the problem that only a plurality of layers of coils adjacent to the supporting strips can be subjected to heat dissipation when the heat dissipation is carried out through the hollow supporting strips is solved.

Various other modifications and changes may be made by those skilled in the art based on the above-described technical solutions and concepts, and all such modifications and changes should fall within the scope of the claims of the present invention.