A cast dry-type transformer and a manufacturing method thereof

Abstract

The application discloses a cast dry-type transformer and a manufacturing method thereof, which comprises a plurality of coils, a core, clamping pieces and lead wires, the lead wires are led out from the coils, the coils are arranged on the core, the coils and the core are fixed together through the clamping pieces on two sides, the coils are provided with a casting mold, the casting mold is provided with uniformly distributed channels, the transformer is cast by placing the body into a casting tank, and the casting material can easily penetrate into the coil through the reserved channels. The novel cast dry-type transformer reduces combustible materials, solves the problems of time consumption of installation of the casting mold, air tightness of the casting mold and permeability of the casting material by using the insulating casting mold and a special casting process, greatly improves the production efficiency of the transformer, and the transformer has lower production cost, is lighter in weight, stronger in overload capacity and easier to maintain.

Description

Technical Field

[0001] This invention relates to three-dimensional wound core transformers, and more particularly to a cast dry-type transformer and its manufacturing method. Background Technology

[0002] With the development of the transformer industry, competition is becoming increasingly fierce. Manufacturers are paying more and more attention to improving production efficiency to reduce production costs, while also continuously improving their products and enhancing the performance of transformers in all aspects to increase their market competitiveness.

[0003] Cast resin dry-type transformers, as a traditional type of dry-type transformer, have been widely used in various indoor buildings due to their advantages such as ease of maintenance and superior electrical performance. However, they have also exposed many problems. First, traditional cast resin dry-type transformers use casting material to cast the coils into a solid form, and the casting material is usually a flammable substance. In the event of a fault, it may catch fire and produce toxic gases. Second, because the casting material is relatively thick, it is prone to cracking in cold regions or under sudden temperature changes, which can lead to faults. When maintenance is required, since each phase coil is encased in the casting material into a solid form, the only way to repair it is to remove the entire coil and rewind it, which is very difficult.

[0004] The traditional production process of cast dry-type transformers is also complex, with the main difficulty lying in the casting process. According to the traditional process, a casting mold needs to be installed before casting, and then the casting material is poured into the mold to form the shape. However, the casting mold is often complex in structure, time-consuming to install, and the casting channel of the mold is narrow. During the casting process, there are often cases where the casting material leaks or some parts are not completely cast, requiring the coil to be repaired. Furthermore, after casting is completed, the mold must be removed and the transformer must be assembled, which can easily damage the cast coil, resulting in frequent rework and low production efficiency. Summary of the Invention

[0005] This application aims to at least partially solve one of the technical problems in the related art. To this end, this application proposes a cast dry-type transformer and its manufacturing method. This novel cast dry-type transformer reduces flammable materials, solves the problems of casting material cracking and transformer maintenance difficulties, and creatively proposes a novel process implementation method. By using an insulating mold and a special casting method, it solves the problems of time-consuming mold installation, mold airtightness, and casting material permeability, greatly improving transformer production efficiency. Furthermore, the transformer produced by this patent has lower production costs, lighter weight, stronger overload capacity, and is easier to maintain.

[0006] The technical solution adopted by this invention to solve its problem is:

[0007] On one hand, an embodiment of the present invention provides a castable dry-type transformer, characterized in that it includes: a plurality of coils, an iron core, clamps, and leads, wherein the leads are led out from the coils, the coils are disposed on the iron core, the coils and the iron core are fixed together by the clamps on both sides, the coils are provided with a casting mold for casting the coils, the casting mold is provided with uniformly distributed channels, the coils are cast with a casting material made of insulating material, wherein the casting mold is made of insulating material and does not need to be disassembled after casting and is combined with the coils to form an integrated structure.

[0008] The aforementioned cast dry-type transformer has at least the following beneficial effects: The casting mold of the present invention is provided with uniformly distributed channels, and the coil is cast with insulating material. Excess casting material can be discharged from the casting mold, reducing the casting thickness. This improves the coil's moisture-proof and corrosion-proof performance while saving materials and reducing costs. The weight of the flammable material in the transformer is significantly reduced compared to traditional cast transformers, improving the transformer's safety and reliability. Furthermore, because the casting material is thinner, the casting channels also serve as heat dissipation channels for the coil, resulting in a large heat dissipation area. This also improves the transformer's heat dissipation capacity and overload capacity, preventing the insulating material from cracking due to sudden temperature changes, shortening the curing time of the insulating material, and improving production efficiency. In addition, the casting mold is detachable. When a problem occurs with the coil and needs to be addressed, it is only necessary to open the casting mold, repair the coil, and then reinstall the casting mold for recasting, making the transformer easier to maintain.

[0009] Furthermore, the iron core adopts a three-dimensional coiled iron core structure, and the iron core includes three single frames. Every two single frames are spliced ​​together at a 60° angle, and a core column is formed at the splicing point of every two single frames.

[0010] Furthermore, each of the single frames is made of several silicon steel sheets or amorphous alloy strips wound together.

[0011] Furthermore, the coil also includes an inner coil and an outer coil, the inner coil being wound between the core and the outer coil, and the leads including inner coil leads and outer coil leads.

[0012] Furthermore, the casting mold includes an inner casting mold and an outer casting mold, with the inner casting mold disposed inside the outer coil and the outer casting mold disposed outside the outer coil.

[0013] Furthermore, both the inner and outer casting molds are made of insulating material. The inner casting mold is a cylindrical structure, and the outer casting mold is a combination of a cylinder and an end ring.

[0014] Furthermore, the outer coil includes a comb-shaped support bar and a wire. The comb-shaped support bar is disposed on the inner casting mold, and the wire is wound around the comb-shaped support bar.

[0015] Furthermore, the comb-shaped support bar includes several evenly spaced long strips, and the wire is wound between the long strips.

[0016] Furthermore, the lead wire includes a first lead wire and a second lead wire, wherein the first lead wire is led out from the inner coil and the second lead wire is led out from the outer coil.

[0017] On the other hand, a method for manufacturing a cast-type dry-type transformer includes a plurality of coils, an iron core, clamps, and leads. The leads are led out from the coils, which are mounted on the iron core. The coils and the iron core are fixed together by clamps on both sides. The coils are provided with a casting mold for casting the coils. The casting mold has evenly distributed channels. The coils are cast with casting material. The casting mold is made of insulating material and, after casting, does not need to be disassembled and is integrated with the coils to form an integral structure. The iron core includes three single frames, with a core column formed at the joint of every two single frames. The coil also includes an inner coil and an outer coil, with the inner coil wound between the core column and the outer coil. The casting mold includes an inner casting mold and an outer casting mold, with the inner casting mold located inside the outer coil and the outer casting mold located outside the outer coil. The outer coil includes comb-shaped support bars and wires. The comb-shaped support bars are located on the inner casting mold and include several evenly spaced strips. The wires are wound between the strips. The method includes the following steps:

[0018] (1) Complete the coil winding and the assembly of the device body, and dry the device body;

[0019] (2) Place the device body into the casting tank and perform vacuum treatment on the device body. Then, inject the degassed casting material into the casting tank so that the liquid level of the casting material is higher than the coil. The casting material is injected from the channel of the casting mold and fills the entire coil.

[0020] (3) Release the vacuum state of the casting tank and pressurize it to inject the casting material into the gap inside the coil;

[0021] (4) After pouring is completed, the excess pouring material in the pouring mold is discharged from the channel;

[0022] (5) Place the vessel body into a drying oven to cure the casting material.

[0023] Further, the coil winding and body assembly are completed, and the body is dried. The steps include:

[0024] (1) The inner coil is wound around the core post of the iron core;

[0025] (2) Wrap the inner mold around the inner side of the outer coil and secure it.

[0026] (3) Fix the comb-shaped support strip to the surface of the casting inner mold. After fixing, wind the wire of the coil between the strips.

[0027] (4) The outer casting mold is wound around the outside of the outer coil, and a channel is reserved between the inner casting mold and the outer casting mold to allow the casting material to be injected or discharged.

[0028] In another embodiment, the casting mold can be installed on the outside of the outer coil after the casting material has cured.

[0029] The above-mentioned manufacturing method for cast dry-type transformers has at least the following beneficial effects: Due to the different casting method, this patent eliminates the need to consider the airtightness of the casting mold. The mold is simple and easy to install. After casting, the casting mold can be directly used as an insulating component of the transformer without disassembly, improving production efficiency. Excess casting material is discharged from the casting mold, reducing the casting thickness. This improves the coil's moisture and corrosion resistance while saving materials and reducing costs. The weight of combustible materials in the transformer is significantly reduced compared to traditional cast transformers, improving the transformer's safety and reliability. Furthermore, because the casting material is thinner, the casting channel also serves as a heat dissipation channel for the coil. The large heat dissipation area improves the transformer's heat dissipation and overload capacity, preventing the insulation material from cracking due to sudden temperature changes, shortening the curing time of the insulation material, and improving production efficiency. Furthermore, during casting, the degassed casting material is injected into the casting tank, and then vacuum and pressure are used to force the casting material through the channels reserved in the casting mold into the coil. Therefore, the casting material easily penetrates into the coil, solving the problem of incomplete coil casting. Moreover, the casting mold is detachable; when a coil problem occurs, it is only necessary to open the casting mold, repair the coil, and then reinstall the casting mold for recasting, making the transformer easier to maintain.

[0030] Additional aspects and advantages of the invention will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. Attached Figure Description

[0031] The preferred embodiments of the present invention are given below with reference to the accompanying drawings to illustrate the implementation of the present invention in detail.

[0032] Figure 1 This is a schematic diagram of a cast-in-place dry-type transformer according to an embodiment of the present invention;

[0033] Figure 2 This is a schematic diagram of the iron core according to an embodiment of the present invention;

[0034] Figure 3 This is a schematic diagram of the coil according to an embodiment of the present invention;

[0035] Figure 4 This is a cross-sectional view of the coil according to an embodiment of the present invention;

[0036] Figure 5 This is a schematic diagram of the comb-shaped support strip according to an embodiment of the present invention;

[0037] Figure 6 This is a flowchart of a method for manufacturing a cast dry-type transformer according to an embodiment of the present invention;

[0038] Figure 7 This is a flowchart of a method for manufacturing a cast dry-type transformer according to an embodiment of the present invention. Detailed Implementation

[0039] This section will describe in detail specific embodiments of the present invention. Preferred embodiments of the present invention are shown in the accompanying drawings. The purpose of the drawings is to supplement the textual description with graphics, so that people can intuitively and vividly understand each technical feature and overall technical solution of the present invention, but they should not be construed as limiting the scope of protection of the present invention.

[0040] In the description of this invention, it should be understood that the orientation descriptions, such as up, down, front, back, left, right, etc., are based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limiting this invention.

[0041] In the description of this invention, unless otherwise explicitly defined, terms such as "set up," "install," and "connect" should be interpreted broadly, and those skilled in the art can reasonably determine the specific meaning of the above terms in this invention in conjunction with the specific content of the technical solution.

[0042] The embodiments of the present invention will now be described in conjunction with the accompanying drawings.

[0043] Reference Figure 1 and Figure 4 This invention provides a castable dry-type transformer, characterized in that it includes: a plurality of coils 100, an iron core 110, a clamp 120, and leads 130. The leads 130 are led out from the coils 100. The coils 100 are disposed on the iron core 110. The coils 100 are provided with a casting mold for casting the coils 100. The casting mold is provided with uniformly distributed channels 101. The coils 100 are cast with a casting material made of insulating material. The casting mold is made of insulating material and does not need to be disassembled after casting and is integrated with the coils 100 to form an integrated structure.

[0044] The aforementioned cast dry-type transformer has at least the following beneficial effects: The casting mold of this invention is provided with uniformly distributed channels 101. The coil 100 is cast with insulating material, allowing excess casting material to be discharged from the casting mold, reducing the casting thickness. This improves the moisture-proof and corrosion-resistant properties of the coil 100 while saving materials and reducing costs. The weight of the flammable material in the transformer is significantly reduced compared to traditional cast transformers, improving the transformer's safety and reliability. Furthermore, because the casting material is thinner, the casting channels 101 also serve as heat dissipation channels for the coil 100, providing a large heat dissipation area. This also improves the transformer's heat dissipation and overload capacity, preventing the insulating material from cracking due to sudden temperature changes, shortening the curing time of the insulating material, and improving production efficiency. In addition, the casting mold is detachable. When a problem occurs with the coil 100 requiring repair, simply open the casting mold, repair the coil 100, reassemble the casting mold, and recast. This makes the transformer easier to maintain.

[0045] Refer to Figure 2 In this embodiment of the invention, the core 110 adopts a three-dimensional wound core structure. The core 110 includes three single frames 111, with each pair of single frames 111 joined together at a 60° angle. A core column 112 is formed at the joint of each pair of single frames 111. Each single frame 111 is wound from several silicon steel sheets or amorphous alloy strips. The three-dimensional wound core transformer is an energy-saving power transformer. It creatively reforms the traditional laminated magnetic circuit structure and three-phase layout of power transformers, resulting in optimized product performance, such as completely symmetrical three-phase magnetic circuits, significant energy-saving effect of the oil-immersed three-dimensional wound core transformer, greatly reduced noise, stronger heat dissipation and overload capacity, and a compact structure and small size.

[0046] In this embodiment of the invention, reference is made to Figure 3 The coil 100 also includes an inner coil 102 and an outer coil 103, with the inner coil 102 wound between the core column 112 and the outer coil 103.

[0047] In this embodiment of the invention, reference is made to Figure 4 The casting mold includes an inner casting mold 141 and an outer casting mold 142. The inner casting mold 141 is located inside the outer coil 103, and the outer casting mold 142 is located outside the outer coil 103. The casting material is injected into the casting mold so that the casting material penetrates into the coil 100.

[0048] In this embodiment of the invention, both the inner casting mold 141 and the outer casting mold 142 are made of insulating material. The inner casting mold 141 is a cylindrical structure, and the outer casting mold 142 is a combination structure of a cylinder and an end ring. After casting, it can be directly used as a transformer insulation component without disassembly, thus improving production efficiency.

[0049] In this embodiment of the invention, reference is made to Figure 4 and Figure 5 The outer coil 103 includes a comb-shaped support bar 104 and a wire 105. The comb-shaped support bar 104 is disposed on the inner mold 141, and the wire 105 is wound on the comb-shaped support bar 104.

[0050] In this embodiment of the invention, reference is made to Figure 5 The comb-shaped support bar 104 includes several evenly spaced strips 1041. The wire 105 is wound in the gap between the strips 1041, so that the gap between the coils 100 is formed, thereby improving the heat dissipation performance of the coils 100 and making it easier to inject and discharge the casting material into the coils 100.

[0051] In this embodiment of the invention, the lead 130 includes an inner coil lead and an outer coil lead, the inner coil lead being led out from the inner coil 102, and the outer coil lead being led out from the outer coil 103.

[0052] Reference Figure 6 A method for manufacturing a cast-type dry-type transformer includes: a plurality of coils 100, an iron core 110, a clamping member 120, and leads 130. The leads 130 are led out from the coils 100. The coils 100 are mounted on the iron core 110. The coils 100 are provided with a casting mold for casting the coils 100. The casting mold has evenly distributed channels 101. The coils 100 are cast with a casting material made of insulating material. The casting mold is made of insulating material and, after casting, does not need to be disassembled and is integrated with the coils 100 to form an integral structure. The iron core 110 includes three single frames 111, with every two single frames 111 joined together at a 60° angle. The joint between every two single frames 111 forms a... The core column 112 and the coil 100 include an inner coil 102 and an outer coil 103. The inner coil 102 is wound between the core column 112 and the outer coil 103. The casting mold includes an inner casting mold 141 and an outer casting mold 142. The inner casting mold 141 is located inside the outer coil 103, and the outer casting mold 142 is located outside the outer coil 103. The outer coil 103 includes comb-shaped support bars 104 and wires 105. The comb-shaped support bars 104 are located on the inner casting mold 141, and the wires 105 are wound on the comb-shaped support bars 104. The comb-shaped support bars 104 include several evenly spaced long strips 1041, and the wires 105 are wound in the gaps between the long strips 1041. The method includes the following steps:

[0053] S100. Complete the coil winding and assemble the device body, and dry the device body;

[0054] S200. Place the body into the casting tank and vacuum the body. Then, inject the degassed casting material into the casting tank so that the liquid level of the casting material is higher than the coil. The casting material is injected from the channel of the casting mold and fills the entire coil.

[0055] S300: Release the vacuum state of the casting tank and pressurize it to inject the casting material into the gap inside the coil;

[0056] S400 After pouring is completed, excess pouring material is discharged from the pouring mold through the channel;

[0057] S500. Place the vessel body into a drying oven to cure the casting material.

[0058] In this embodiment, refer to Figure 7 The coil winding and body assembly are completed, and the body is dried. The steps include:

[0059] S101. Wind the inner coil onto the core post of the iron core;

[0060] S102. Wrap the inner mold around the inner coil of the outer coil and secure it.

[0061] S103. Fix the comb-shaped support strip to the surface of the casting inner mold. After fixing, wrap the wire of the coil around the strip.

[0062] S104. The outer mold is wound around the outside of the outer coil, and a channel is reserved between the inner mold and the outer mold to allow the casting material to be injected or discharged.

[0063] In another embodiment, the casting mold can be installed on the outside of the outer coil after the casting material has cured.

[0064] The above-mentioned manufacturing method for cast dry-type transformers has at least the following beneficial effects: Due to the different casting method, this patent eliminates the need to consider the airtightness of the casting mold. The mold is simple and easy to install. After casting, the casting mold can be directly used as an insulating component of the transformer without disassembly, improving production efficiency. Excess casting material is discharged from the casting mold, reducing the casting thickness. This improves the moisture and corrosion resistance of the coil 100 while saving materials and reducing costs. The weight of combustible material in the transformer is significantly reduced compared to traditional cast transformers, improving the transformer's safety and reliability. Furthermore, because the casting material is thinner, the casting channel 1... 01 also serves as the heat dissipation channel for coil 100, with a large heat dissipation area. This improves the transformer's heat dissipation and overload capacity, prevents the insulation material from cracking due to sudden temperature changes, shortens the curing time of the insulation material, and improves production efficiency. In addition, during casting, the degassed casting material is injected into the casting tank. The casting material easily penetrates into the interior of coil 100 through the reserved channels, solving the problem of incomplete casting of coil 100. Furthermore, the casting mold is detachable. When a problem occurs with the coil and needs to be repaired, it is only necessary to open the casting mold, wrap and repair the coil, and then reinstall the casting mold for recasting, making the transformer easier to maintain.

[0065] The above content provides a detailed description of the preferred embodiments and basic principles of the present invention. However, the present invention is not limited to the above-described embodiments. Those skilled in the art should understand that various equivalent modifications and substitutions may be made without departing from the spirit of the present invention, and all such equivalent modifications and substitutions fall within the scope of the present invention as claimed.

Claims

1. A cast-in-place dry-type transformer, characterized in that, include: The system comprises several coils, an iron core, clamps, and leads. The leads are led out from the coils, which are mounted on the iron core. The coils and the iron core are fixed together by clamps on both sides. Each coil includes an inner coil and an outer coil. A casting mold for casting the coil is provided at the outer coil. The casting mold includes an inner casting mold and an outer casting mold made of insulating material. The casting mold has evenly distributed channels that allow casting material to enter and exit, and also serve as heat dissipation channels for the coil. The coil is thinly coated by the outward discharge of excess casting material to reduce the amount of flammable material used. The outer coil is equipped with comb-shaped support bars, the gaps between which are connected to the channels to form a heat dissipation pathway. The coil is filled with casting material.

2. A cast-in-place dry-type transformer according to claim 1, characterized in that: The iron core adopts a three-dimensional coiled iron core structure. The iron core includes three single frames. Every two single frames are spliced ​​together at a 60° angle, and a core column is formed at the splicing point of every two single frames.

3. A cast-in-place dry-type transformer according to claim 2, characterized in that: The inner coil is wound between the core column and the outer coil. The inner casting mold is located inside the outer coil, and the outer casting mold is located outside the outer coil. The lead wires include inner coil lead wires and outer coil lead wires.

4. A cast-in-place dry-type transformer according to claim 3, characterized in that: The inner casting mold is a cylindrical structure, and the outer casting mold is a combination of a cylinder and an end ring.

5. A cast-in-place dry-type transformer according to claim 3, characterized in that: The outer coil includes a wire, the comb-shaped support is disposed on the inner mold of the casting, and the wire is wound around the comb-shaped support.

6. A cast-in-place dry-type transformer according to claim 5, characterized in that: The comb-shaped support bar comprises several evenly spaced long strips, and the wire is wound between the long strips.

7. A cast-in-place dry-type transformer according to claim 2, characterized in that: Each of the aforementioned frames is made of several silicon steel sheets or amorphous alloy strips.

8. A method for manufacturing a cast dry-type transformer, characterized in that: The cast-in-place dry-type transformer includes several coils, an iron core, clamps, and leads. The leads are led out from the coils, which are mounted on the iron core. The coils and the iron core are fixed together by the clamps on both sides. The coils are provided with a casting mold for casting the coils. The casting mold has evenly distributed channels. The coils are cast with casting material. The casting mold is made of insulating material and does not need to be disassembled after casting, forming an integrated structure with the coils. The iron core includes three single frames, each... The two single-frame splices form a core column. The coil further includes an inner coil and an outer coil. The inner coil is wound between the core column and the outer coil. The casting mold includes an inner casting mold and an outer casting mold. The inner casting mold is located inside the outer coil, and the outer casting mold is located outside the outer coil. The outer coil includes comb-shaped support bars and wires. The comb-shaped support bars are located on the inner casting mold. The comb-shaped support bars include several evenly spaced long strips. The wires are wound between the long strips. The method includes the following steps: ① Complete the coil winding and the assembly of the device body, and dry the device body; ② Place the device body into the casting tank and perform vacuum treatment on the device body. Then, inject the degassed casting material into the casting tank so that the liquid level of the casting material is higher than the coil. The casting material is injected from the channel of the casting mold and fills the entire coil. ③ Release the vacuum state of the casting tank and pressurize it to inject the casting material into the gap inside the coil; ④ After pouring is completed, the excess pouring material in the pouring mold is discharged from the channel; ⑤ Place the vessel body into a drying oven to cure the casting material.

9. A method for manufacturing a cast dry-type transformer according to claim 8, characterized in that: The steps to complete the coil winding and body assembly, and to dry the body, include: ① The inner coil is wound around the core post of the iron core; ② Wrap the inner mold around the inside of the outer coil to be formed and secure it. ③ Fix the comb-shaped support strip to the surface of the casting inner mold. After fixing, wind the wire of the coil between the strips. ④ The outer casting mold is wound around the outside of the outer coil, and a channel is reserved between the inner casting mold and the outer casting mold to allow the casting material to be injected or discharged.

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