High-voltage coil structure of high-voltage dry-type transformer and winding method

Abstract

The invention relates to the electrical field, and discloses a high-voltage coil structure of a high-voltage dry-type transformer and a winding method, the high-voltage coil structure comprises a copper conductor for manufacturing a coil, and a connector is led out from the winding tail end of the coil; the copper conductor is divided into an E1 section, an F1 section, a G1 section and an H1 section, the upper half part of the coil is divided into an F1 section coil and an E1 section coil from the middle section to the outer end, the lead end of the F1 section coil starts from the first layer of the middle position of the E1 section and the F1 section in the copper conductor, the lower half part of the coil is divided into a G1 section coil and an H1 section coil from the middle section to the outer end, and the lead end of the G1 section coil starts from the first layer of the middle position of the G1 section and the H1 section in the copper conductor; the number of layers of the E1-segment coil, the F1-segment coil, the G1-segment coil and the H1-segment coil is the same, the G1-segment coil and the F1-segment coil are symmetrical, and the E1-segment coil and the H1-segment coil are symmetrical; compared with a coil wound by a traditional pyramid structure, the high-voltage coil wound in a multi-section mode is smaller in size, the number of consumed copper materials and silicon steel sheets is reduced, and the cost for manufacturing the dry-type transformer is reduced.

Description

Technical Field

[0001] The invention relates to the electrical field, and in particular to a high-voltage coil structure and a winding method for a high-voltage dry-type transformer. Background Art

[0002] The structure of the high-voltage coil of a dry-type transformer is mainly composed of a core column, a multi-section cylindrical coil and an insulating material. In China, the high-voltage coil of a 10-35kV non-excitation voltage-regulating dry-type transformer generally adopts a pyramid-shaped multi-section layered structure. At present, the price of raw materials remains high, especially the price of copper and silicon steel sheets. According to the latest material prices, the price of copper conductors is basically maintained at 4-5 times the price of silicon steel sheets. Therefore, in the manufacture of dry-type transformers, how to reduce the use of copper materials is the key to reducing costs.

[0003] The amount of copper and silicon steel sheets in the product are the two main materials that account for the largest proportion of the cost. The usage of copper and silicon steel sheets is directly related to the winding method of the high-voltage coil. The coil wound by the traditional pyramid multi-stage layered structure is large in volume, and the corresponding coil requires a large number of copper and silicon steel sheets, and the cost of preparing dry-type transformers is high. Summary of the invention

[0004] In view of the above problems, a high-voltage coil structure and a winding method for a high-voltage dry-type transformer are provided. By winding the high-voltage coil with a multi-segment layered structure, the problems of large coil volume wound with a traditional pyramid multi-segment layered structure, a large number of copper and silicon steel sheets required for the corresponding coil, and high cost of preparing a dry-type transformer are solved.

[0005] In order to solve the problems of the prior art, the present invention provides a high-voltage dry-type transformer high-voltage coil structure, including a copper conductor wound with a coil, a connecting head leading out of the coil winding tail end, and an insulating resin filled in a mold after the coil winding is completed; the copper conductor is divided into E 1 Duan, F 1 Duan, G 1 Duan and H 1 The upper part of the coil is divided into F from the middle to the outer end. 1 、E 1 Two coils, F 1 The wire ends of the segment coil start from the copper conductor E 1 、F 1 The first layer in the middle of the segment, the lower half of the coil, is divided into G from the middle to the outer end 1 , H 1 Two-stage coil, G 1 The wire ends of the segment coil start from the copper conductor G 1 , H 1 The first layer in the middle of the segment; E 1 Duan, F 1 Duan, G 1Duan and H 1 The number of coil layers is the same, G 1 Segment coil and F 1 The segment coil is symmetrical, E 1 Segment coil and H 1 The segment coils are symmetrical.

[0006] Preferably, the coil is wound from the middle position of the copper conductor toward the outer end in a first layer, and then wound in the reverse direction to the second layer, and a complete coil structure is formed by reverse winding between each layer.

[0007] Preferably, the E 1 Duan and F 1 Duan, G 1 Duan and H 1 The coils connected between the segments are connected in a through-winding manner.

[0008] Preferably, the F 1 The inner layer of the segment coil has several taps, marked as tap 4 and tap 6, and the seventh layer is wound to form a complete F 1 Segment coil, lead out the upper end 2; F 1 The segment coil is wound to E using the through-winding process. 1 Segment, winding to the seventh layer to form a complete E 1 Segment coil, lead out the lower end A (B, C).

[0009] Preferably, the G 1 The inner layer of the segment coil has several taps, marked as tap 5 and tap 7, and the seventh layer is wound to form a complete G 1 Segment coil, lead out the upper end 3; G 1 The segment coil is wound to H by through winding process 1 The seventh layer forms a complete H 1 Segment coil, lead out the lower end X (Y, Z).

[0010] Preferably, the F 1 Segment coil and G 1 The segment coils are arranged in a pyramid structure.

[0011] Preferably, the F 1 Duan, G 1 The number of layers of the segment coil is the same from the second layer onwards, and the number of turns of each group of coils gradually decreases toward the end.

[0012] Preferably, the E 1 Segment coil and H 1 The segment coils are arranged in a rectangular structure. 1 Segment coil and H 1 The number of turns in each layer of the segment coil is the same.

[0013] Preferably, the insulating resin is made of epoxy resin material.

[0014] The present invention also includes a method for winding a high-voltage coil of a high-voltage dry-type transformer, having the above-mentioned high-voltage coil structure of a high-voltage dry-type transformer, comprising the following steps:

[0015] S1. Preparation of winding mold: prepare the mold according to the copper conductor arrangement structure, and polish and rust-proof the mold surface.

[0016] S2. Applying a release agent: evenly apply the release agent on the mold surface.

[0017] S3. To make a conductor, the copper wire with a smooth surface is insulated. The insulation treatment method includes wrapping two layers of insulating glass ribbon on the front and back of the outer surface of the copper wire to make a conductor.

[0018] S4. Laying of epoxy glass fiber mesh: Wrap three layers of epoxy glass fiber mesh on the bottom layer of the mold as insulation material.

[0019] S5, cylindrical winding, the conductor is wound cylindrically on a mold wrapped with an epoxy glass fiber mesh.

[0020] S6, Segmentation method, the high voltage coil is divided into 4 sections, namely E 1 Duan, F 1 Duan, G 1 Duan and H 1 Segment, coil at E 1 Duan and F 1 Duan, G 1 Duan and H 1 The segments are wound to form two parts: the upper and lower parts; the upper part of the coil is divided into F from the middle to the outer end 1 、E 1 Two coils, F 1 The wire ends of the segment coils start from die E 1 、F 1 The first layer is wound from the middle of the mold to the outer end of the mold, and then the second layer is wound in the reverse direction. This is repeated until the first layer is wound. 1 The inner layer of the inner coil of the segment coil is connected to the inter-group position, and the winding is completed to the ninth layer to form F 1 The upper end 2 is led out of the coil, and then the lower end of the wire is wound to E using the through-winding process. 1 The left end of the outer side of the segment coil continues to wind E 1 Segment coil, refer to F 1 The winding method of the segment coil is wound. After the winding is completed, in the E 1 The end of the wire of the segment coil is connected to a connector A (B, C); the G 1 Paragraph and F1 Segment symmetry, H 1 Section E 1 The segments are symmetrical, and the number of layers between each segment of the coil is the same. During the winding process, multiple taps 5 and 7 are led out from the inner layer of the G1 segment of the coil to the position between the groups; and from the H 1 The end of the wire segment leads to connector X (Y, Z).

[0021] S7, curing and molding, molding the wound high-voltage coil and pouring epoxy resin under vacuum conditions for insulation filling, and obtaining the dry-type transformer high-voltage coil after curing and molding.

[0022] Compared with the prior art, the present invention has the following beneficial effects:

[0023] 1. The present invention adopts a segmented structure to wind the high-voltage coil of the dry-type transformer, E 1 Duan and H 1 The number of turns of each layer of the winding coil in the segment is the same, F 1 Duan, G 1 The number of turns of the segment winding coil gradually decreases in a step-like manner. After the four-segment coil is wound, the coil volume is smaller than that formed by the traditional pyramid multi-segment layered structure. The amount of copper and silicon steel sheets used in conjunction with the coil is reduced, effectively reducing the manufacturing cost of the dry-type transformer.

[0024] 2. The present invention uses a multi-stage layered structure, and the tapping position is made in the form of an inner tapping tap. The dry-type transformer adopts this structural coil. Through structural improvement, it can not only ensure the insulation distance, reduce the electric field strength between segments, make the electric field distribution inside the coil more uniform, and improve the quality of the product, but also because of the use of a through-winding process, the filling rate of the coil can be effectively improved. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 The invention discloses a structural schematic diagram of a coil layer winding method for a high-voltage coil structure of a high-voltage dry-type transformer.

[0026] Figure 2 The present invention is a schematic diagram of a high-voltage coil structure in which the high-voltage coil of a traditional high-voltage dry-type transformer is arranged in a pyramid-shaped stepped structure in each section.

[0027] Figure 3 The invention is a schematic diagram of the connection of the high-voltage coil turns of a high-voltage dry-type transformer high-voltage coil structure.

[0028] Figure 4 It is a schematic diagram of the traditional high-voltage dry-type transformer with each section of the coil arranged in a stepped structure and the number of high-voltage coil turns connected.

[0029] Figure 5 The utility model is a schematic diagram of the high-voltage coil tapping of the high-voltage coil structure of a high-voltage dry-type transformer.

[0030] The numbers in the figure are:

[0031] 11. Copper conductor; 12. Connector; 13. Insulating resin. DETAILED DESCRIPTION

[0032] In order to further understand the features, technical means, specific objectives and functions of the present invention, the present invention is further described in detail below in conjunction with the accompanying drawings and specific implementation methods.

[0033] See also Figure 1 , Figure 3 and Figure 5 As shown, a high-voltage dry-type transformer high-voltage coil structure includes a copper conductor 11 for winding the coil, a connector 12 for leading out the coil winding tail end, and an insulating resin 13 filled in the mold after the coil winding is completed; the copper conductor 11 is divided into E 1 Duan, F 1 Duan, G 1 Duan and H 1 The upper part of the coil is divided into F from the middle to the outer end. 1 、E 1 Two coils, F 1 The wire end of the segment coil starts from E in the copper conductor 11 1 、F 1 The first layer in the middle of the segment, the lower half of the coil, is divided into G from the middle to the outer end 1 , H 1 Two-stage coil, G 1 The wire end of the segment coil starts from the copper conductor 11 G 1 , H 1 The first layer in the middle of the segment; E 1 Duan, F 1 Duan, G 1 Duan and H 1 The number of coil layers is the same, G 1 Segment coil and F 1 The segment coil is symmetrical, E 1 Segment coil and H 1 The segment coils are symmetrical.

[0034] See also Figure 1 , Figure 3 and Figure 5 As shown, the coil is wound from the middle position of the copper conductor 11 toward the outer end for the first layer, and then reversely wound to the second layer, and reverse winding is adopted between each layer to form a complete coil structure.

[0035] See also Figure 1 , Figure 3 and Figure 5 As shown, E 1 Duan and F1 Duan, G 1 Duan and H 1 The coils connected between the segments are connected by through-winding; the through-winding coils do not need to be welded.

[0036] See also Figure 1 , Figure 3 and Figure 5 As shown, F 1 The inner layer of the segment coil has several taps, marked as tap 4 and tap 6, and the seventh layer is wound to form a complete F 1 Segment coil, lead out the upper end 2; F 1 The segment coil is wound to E using the through-winding process. 1 Segment, winding to the seventh layer to form a complete E 1 Segment coil, lead out the lower end A (B, C).

[0037] See also Figure 1 , Figure 3 and Figure 5 As shown, G 1 The inner layer of the segment coil has several taps, marked as tap 5 and tap 7, and the seventh layer is wound to form a complete G 1 Segment coil, lead out the upper end 3; G 1 The segment coil is wound to H by through winding process 1 The seventh layer forms a complete H 1 Segment coil, lead out the lower end X (Y, Z).

[0038] See also Figure 1 , Figure 3 and Figure 5 As shown, F 1 Segment coil and G 1 The segment coils are arranged in a pyramid structure.

[0039] See also Figure 1 , Figure 3 and Figure 5 As shown, F 1 Duan, G 1 The number of layers of the segment coil is the same from the second layer onwards, and the number of turns of each group of coils gradually decreases toward the end.

[0040] See also Figure 1 , Figure 3 and Figure 5 As shown, E 1 Segment coil and H 1 The segment coils are arranged in a rectangular structure. 1 Segment coil and H 1 The number of turns in each layer of the segment coil is the same.

[0041] See also Figure 1 , Figure 3 and Figure 5 As shown, the insulating resin 13 is made of epoxy resin material; epoxy resin is an excellent insulating material with high dielectric properties, resistance to surface leakage and arc resistance.

[0042] Considering that the high-voltage coil structure of the traditional high-voltage dry-type transformer is a pyramid-shaped multi-stage layered structure, the number of turns of each layer decreases from the inner layer to the outer layer, and the number of turns of each layer must be adjusted during winding. The present invention proposes a new rectangular structure. The uniformity of the winding structure and the through-winding process will greatly improve the production efficiency, thereby effectively reducing the manufacturing cost of the transformer.

[0043] The following uses a dry-type transformer high-voltage coil with a total number of turns of 188 as an example to compare the difference between the winding of a traditional dry-type transformer high-voltage coil and the winding of the coil of the present invention.

[0044] like Figure 2 and Figure 4 As shown, the high-voltage coil of the traditional high-voltage dry-type transformer is a pyramid multi-section layer structure. The coil distribution structure of the E section, F section, G section and H section is the same. Each section is divided into nine layers, and the number of turns of the coils from the first layer to the ninth layer in each section are 7 turns, 7 turns, 6 turns, 6 turns, 5 turns, 5 turns, 4 turns, 4 turns and 3 turns respectively. The number of turns of each coil is 47 turns. The total number of turns of the four sections of the E section, the F section, the G section and the H section is 47×4=188 turns. The traditional high-voltage coil with 188 turns is a nine-layer structure with a large volume. The amount of copper and silicon steel sheets used is large. The coils of the E section and the F section, the G section and the H section are wound in a conventional manner. The connection of the coils after winding needs to be welded, which increases the preparation process.

[0045] like Figure 1 , Figure 3 and Figure 5 As shown, the high-voltage coil of the high-voltage dry-type transformer in the present invention adopts a 4-segment structure, namely, E 1 Duan, F 1 Duan, G 1 Duan and H 1 Each section is set to a seven-layer structure. The average number of turns of each layer is calculated. That is, 188 / 4 / 7 is rounded up to 7, so the number of turns of the first layer of each section is 7, E 1 Segment and F 1 Duan, G 1 Segment and H 1 The coils of the segments are wound together, 1 Duan and F 1 Segment-wound coil and G 1 Duan and H 1 The number of turns of the coil is the same, with E 1 Duan and F 1 For example, E 1 Duan and F1 The total number of turns of the first layer of the segment plus the through-wound coil is 7+7+2=16 turns. In order to ensure the insulation performance between each segment and reduce the partial discharge inside the coil, F 1 Duan He G 1 The segment adopts a pyramid-shaped multi-layer structure. 1 Duan He G 1 The number of turns of the segment from the 2nd layer to the 7th layer are 7 turns, 7 turns, 6 turns, 6 turns, 5 turns, and 5 turns respectively, so F 1 Duan He G 1 The total number of turns of the coil from the 2nd to the 7th layer is 7+7+6+6+5+5=36 turns, and E 1 Duan and H 1 The segments are arranged in a rectangular structure. 1 Duan and H 1 The number of turns of each layer of coil is the same, that is, E 1 Duan and H 1 The total number of turns of each segment except the first pass winding is 7×6=42 turns. According to the above winding method, the total number of turns of the high-voltage coil of the high-voltage dry-type transformer in the present invention is 16×2+42×2+36×2=188 turns. According to the specified production process and detailed requirements, the winding of each segment of all segments of the high-voltage coil and the lead-out of each level tap 2, 4, 6, 3, 5, 7 and the first and tail end taps A (B, C), X (Y, Z) are completed. The coil wound in this way only needs to be arranged into a seven-layer structure under the condition of the same number of turns. The volume of the prepared high-voltage coil is smaller, the filling rate of the coil can be effectively improved, and the corresponding consumption of copper and silicon steel sheets of the coil is reduced, thereby reducing the cost of preparing the high-voltage dry-type transformer.

[0046] For the traditional high-voltage dry-type transformer structure, each section of the high-voltage coil adopts a pyramid-shaped stepped structure. The high-voltage coil with a total number of turns of 188 turns can only be set as a 4-section nine-layer coil arrangement structure according to the structural arrangement of the traditional high-voltage dry-type transformer coil. The structure and turn connection method of the high-voltage coil of the dry-type transformer formed by the winding method provided by the present invention can be optimized to be set as a 4-section seven-layer coil arrangement structure. For the original 10kV dry-type transformer with 4 sections and nine layers, the total number of turns of the 4-section coil is 188 turns. Under the same condition, the number of layers of the coil winding structure provided by the present invention can be reduced by two layers, or in the same size space, 48 more turns of wire can be arranged under the condition that the number of layers is nine layers unchanged. Therefore, the high-voltage coil of the dry-type transformer formed by the winding method provided by the present invention is smaller in size. Without reducing product reliability and increasing production equipment, the coil turn length can be reduced, the weight of the copper wire used can be reduced, and the length of the silicon steel sheet of the iron choke of the core part can be reduced, thereby reducing the number of silicon steel sheets used, and the overall cost of the dry-type transformer can be effectively reduced by more than 5%.

[0047] The present invention also includes a method for winding a high-voltage coil of a high-voltage dry-type transformer, having the above-mentioned high-voltage coil structure of a high-voltage dry-type transformer, comprising the following steps:

[0048] S1. Preparation of winding mold: prepare the mold according to the arrangement structure of copper conductor 11, and polish and rust-proof the mold surface.

[0049] S2. Applying a release agent: evenly apply the release agent on the mold surface.

[0050] S3. Make conductors and insulate the smooth copper wires.

[0051] S4. Laying of epoxy glass fiber mesh: Wrap three layers of epoxy glass fiber mesh on the bottom layer of the mold as insulation material.

[0052] S5, cylindrical winding, the conductor is wound cylindrically on a mold wrapped with an epoxy glass fiber mesh.

[0053] S6, Segmentation method, the high voltage coil is divided into 4 sections, namely E 1 Duan, F 1 Duan, G 1 Duan and H 1 Segment, coil at E 1 Duan and F 1 Duan, G 1 Duan and H 1 The segments are wound to form two parts: the upper and lower parts; the upper part of the coil is divided into F from the middle to the outer end 1 、E 1 Two coils, F 1 The wire ends of the segment coils start from die E 1 、F 1 The first layer is wound from the middle of the mold to the outer end of the mold, and then the second layer is wound in the reverse direction. This is repeated until the first layer is wound. 1 The inner layer of the inner coil of the segment coil is connected to the inter-group position, and the winding is completed to the ninth layer to form F 1 The upper end 2 is led out of the coil, and then the lower end of the wire is wound to E using the through-winding process. 1 The left end of the outer side of the segment coil continues to wind E 1 Segment coil, refer to F 1 The winding method of the segment coil is wound. After the winding is completed, in the E 1 The end of the wire of the segment coil is connected to a connector A (B, C); the G 1 Paragraph and F 1 Segment symmetry, H 1 Section E 1The segments are symmetrical, and the number of layers between each segment of the coil is the same. During the winding process, multiple taps 5 and 7 are led out from the inner layer of the G1 segment of the coil to the position between the groups; and from the H 1 A connector X (Y, Z) is led out from the tail end of the segment wire.

[0054] S7, curing and molding, molding the wound high-voltage coil and pouring epoxy resin under vacuum conditions for insulation filling, and obtaining the dry-type transformer high-voltage coil after curing and molding.

[0055] The above embodiments only express one or several implementation modes of the present invention, and the description thereof is relatively specific and detailed, but it cannot be understood as limiting the scope of the present invention. It should be pointed out that, for those of ordinary skill in the art, several variations and improvements can be made without departing from the concept of the present invention, and these all belong to the protection scope of the present invention. Therefore, the protection scope of the present invention shall be subject to the attached claims.

Claims

1. A high voltage dry-type transformer high voltage coil structure, characterized in that: It includes a copper conductor (11) for winding a coil, a connecting head (12) for leading out the tail end of the coil, and an insulating resin (13) for filling the mold after the coil is wound; The copper conductor (11) is divided into E 1 Duan, F 1 Duan, G 1 Duan and H 1 The upper part of the coil is divided into F from the middle to the outer end. 1 、E 1 Two coils, F 1 The wire ends of the segment coil start from the copper conductor (11) E 1 、F 1 The first layer in the middle of the segment, the lower half of the coil, is divided into G from the middle to the outer end 1 , H 1 Two-stage coil, G 1 The wire ends of the segment coil start from the copper conductor (11) G 1 , H 1 The first layer in the middle of the segment; E 1 Duan, F 1 Duan, G 1 Duan and H 1 The number of coil layers is the same, G 1 Segment coil and F 1 The segment coil is symmetrical, E 1 Segment coil and H 1 The segment coils are symmetrical.

2. The high voltage coil structure of a high voltage dry-type transformer according to claim 1, characterized in that: The coil is wound from the middle position of the copper conductor (11) toward the outer end in a first layer, and then wound in the reverse direction to a second layer, with each layer being wound in the reverse direction to form a complete coil structure.

3. The high voltage coil structure of a high voltage dry-type transformer according to claim 2, characterized in that: The E 1 Duan and F 1 Duan, G 1 Duan and H 1 The coils connected between the segments are connected in a through-winding manner.

4. The high voltage coil structure of a high voltage dry-type transformer according to claim 1, characterized in that: The F 1 The inner layer of the segment coil has several taps, marked as tap 4 and tap 6, and the seventh layer is wound to form a complete F 1 Segment coil, leading out the upper end 2; F 1 The segment coil is wound to E using the through-winding process. 1 Segment, winding to the seventh layer to form a complete E 1 Segment coil, lead out the lower end A (B, C).

5. The high voltage coil structure of a high voltage dry-type transformer according to claim 1, characterized in that: The G 1 The inner layer of the segment coil has several taps, marked as tap 5 and tap 7, and the seventh layer is wound to form a complete G 1 Segment coil, leading out the upper end 3; G 1 The segment coil is wound to H by through winding process 1 The seventh layer forms a complete H 1 Segment coil, lead out the lower end X (Y, Z).

6. The high voltage coil structure of a high voltage dry-type transformer according to claim 1, characterized in that: The F 1 Segment coil and G 1 The segment coils are arranged in a pyramid structure.

7. A high voltage dry-type transformer high voltage coil structure according to claim 6, characterized in that: The F 1 Duan, G 1 The number of layers of the segment coil is the same from the second layer onwards, and the number of turns of each group of coils gradually decreases toward the end.

8. The high voltage coil structure of a high voltage dry-type transformer according to claim 6, characterized in that: The E 1 Segment coil and H 1 The segment coils are arranged in a rectangular structure. 1 Segment coil and H 1 The number of turns in each layer of the segment coil is the same.

9. The high voltage coil structure of a high voltage dry-type transformer according to claim 1, characterized in that: The insulating resin (13) is made of epoxy resin material.

10. A method for winding a high voltage coil of a high voltage dry-type transformer, characterized in that: A high voltage dry-type transformer high voltage coil structure applied to any one of claims 1 to 9 comprises the following steps: S1, preparation of winding mold, preparation of the mold according to the arrangement structure of the copper conductor (11), and polishing and rust-proofing of the mold surface; S2, mold release agent coating, evenly coating the mold release agent on the mold surface; S3, making conductors and insulating the copper wires with smooth surfaces; S4, laying of epoxy glass fiber mesh, winding three layers of epoxy glass fiber mesh as insulation material on the bottom layer of the mold; S5, cylindrical winding, the conductor is wound on a mold wrapped with epoxy glass fiber mesh by a cylindrical winding method; S6, Segmentation method, the high voltage coil is divided into 4 sections, namely E 1 Duan, F 1 Duan, G 1 Duan and H 1 Segment, coil at E 1 Duan and F 1 Duan, G 1 Duan and H 1 The segments are wound to form upper and lower parts; S7, curing and molding, molding the wound high-voltage coil and pouring epoxy resin under vacuum conditions for insulation filling, and obtaining the dry-type transformer high-voltage coil after curing and molding.

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