A transformer and a method of winding a coil thereof

Abstract

The present application relates to a kind of transformer and its coil winding method, belong to transformer manufacturing technical field, when winding upper section of high voltage coil, high voltage coil head is introduced in high voltage side axial end, and the end insulation of first and last layer turns is placed, interlayer is added pad insulating material, and upper section of high voltage coil is sequentially completed winding, and the tap-out head of upper section of high voltage coil is introduced from high voltage side axial middle part;When winding lower section of high voltage coil, the tap-out head of lower section of high voltage coil is introduced from high voltage side axial middle part, and the end insulation of first and last layer turns is placed, interlayer is added pad insulating material, and lower section of high voltage coil is sequentially completed winding, and the tail of high voltage coil is introduced in high voltage side axial middle part, not only need not to change direction when winding high voltage coil, avoid to remove winding machine, mould, wire and other equipment, but also effectively shorten the length of tap-out lead in transformer, avoid the problem that coil amplitude cannot be fixed after connecting lead is introduced, also reduce the volume of transformer.

Description

Technical Field

[0001] This invention relates to a transformer and its coil winding method, belonging to the field of transformer manufacturing technology. Background Technology

[0003] With the increasing number of new energy power generation projects, transformers, as key equipment for power transmission, face the challenges of fluctuating power generation. They need to frequently cope with load changes and voltage and current surges, leading to accelerated insulation aging. Wind farms are typically located in remote areas, such as offshore or at high altitudes, facing salt spray, humidity, and low temperatures; photovoltaic power plants may be located in desert areas, experiencing high temperatures and dust storms. In these extreme environments, transformer failure rates are higher. The transformer coil, as the core component that directly carries voltage and current, is particularly vulnerable to failures in insulation strength, heat dissipation, and short-circuit withstand capabilities under these operating conditions.

[0004] The existing method for winding transformer coils involves winding the low-voltage coil using a low-voltage coil winding die and winding the high-voltage coil using a high-voltage coil winding die (e.g., ...). Figure 1 The diagram shown illustrates the winding of the high-voltage coil in a transformer according to existing technology. The high-voltage coil is wound starting from point A, proceeding from left to right, completing one layer of winding. After increasing the number of layers, layers 2 through 14 are wound sequentially. Taps X6 / X4 / X2 are led out from the surface of the upper half of the coil. After the upper half of the winding is completed, the coil needs to be rotated 180° to bring the lower half to the original position of the upper half. Starting from X, the winding proceeds from left to right, completing one layer. After increasing the number of layers, layers 2 through 14 are wound sequentially (tap connectors X7 / X5 / X3 are led out from the surface of the upper half of the coil). Then, an insulating layer and support bars are placed around the low-voltage coil to enclose it. The insulating layer provides insulation and also helps cool the coil by introducing insulating fluid. However, during use, the outer diameter of the low-voltage coil is difficult to standardize due to uneven winding and other external factors, resulting in a loose fit between the low-voltage and high-voltage coils. Furthermore, to improve the coil's withstand voltage, the high-voltage coil is currently divided into upper and lower sections, either winding the upper half first and then the lower half, or vice versa. However, a reversal is required during winding; otherwise, the winding direction will be reversed. To ensure that the upper and lower halves of the coil are wound from left to right, the coil needs to be rotated 180 degrees. When reversing the direction, the winding machine, mold, wires, etc. must be removed, which is inefficient and wastes time.

[0005] In addition, such as Figure 2The diagram shows the structure of the transformer body and tap changer leads in the prior art. The upper clamp 6 of the transformer is made of metal. During operation, leakage flux from the coil causes eddy current losses in the metal components, leading to overheating of the upper clamp 6, increased transformer losses, and a higher temperature rise. The tap changer leads 13 extend from the surface of the coil 10 and connect to the tap changer 14, resulting in a long lead length. This makes it difficult to secure the tap changer leads 13, leading to a whipping effect under the short-circuit electromagnetic force, causing displacement or breakage of the tap changer leads 13. The long lead length, extending from the bottom to the top of the transformer, is also detrimental to the insulation treatment of the tap changer leads 13, leading to insulation breakdown between different phase tap changers 13 and to the upper clamp 6, core 1, and other metal structural components under the short-circuit electromagnetic force. Furthermore, the long tap changer leads 13 require numerous fixing and insulation protection measures, resulting in poor economic efficiency. Summary of the Invention

[0006] The purpose of this invention is to provide a method for winding transformer coils, thereby improving the winding efficiency of transformer coils. Another purpose of this invention is to provide a transformer that solves the problem of eddy current losses caused by the upper clamp made of metal, and to solve the problem of long tap leads leading to difficulty in fixing and easy breakdown.

[0007] To achieve the above objectives, in one aspect, the present invention provides a method for winding a transformer coil, comprising: After the low-voltage coil is wound, an insulating layer is wound on the outer surface of the low-voltage coil, and a high-voltage coil is wound on the outside of the insulating layer; wherein, the high-voltage coil is divided into upper and lower sections; When winding the upper section of the high-voltage coil, the beginning of the high-voltage coil is led out at the axial end of the high-voltage side, and after the upper section of the high-voltage coil is wound, the tap of the upper section of the high-voltage coil is led out from the axial middle of the high-voltage side. When winding the lower section of the high-voltage coil, the tap of the lower section of the high-voltage coil is led out from the middle of the high-voltage side, and after the lower section of the high-voltage coil is wound, the tail of the high-voltage coil is led out from the middle of the high-voltage side.

[0008] Furthermore, the high-voltage coil adopts a multi-layer cylindrical structure, with an upper pad provided outside the top insulation layer of the upper section of the high-voltage coil; a middle pad provided between the upper section and the lower section of the high-voltage coil; and a lower pad provided at the bottom of the lower section of the high-voltage coil.

[0009] Furthermore, several layers of axially connected heat dissipation channels are provided between the upper section and the lower section of the high-voltage coil. Before the high-voltage coil is wound, several layers of axially penetrating heat dissipation channels are set between the low-voltage coil and the high-voltage coil. Among these layers, one axially penetrating heat dissipation channel is used to place the end corner ring of the high-voltage coil.

[0010] Furthermore, when winding the upper section of the high-voltage coil, the beginning of the high-voltage coil is led out at the axial end of the high-voltage side, and end insulation is placed at the beginning and end of each layer of coil turns. Insulating material is added between layers. The upper section of the high-voltage coil is wound in sequence, and the tap of the upper section of the high-voltage coil is led out from the middle of the axial direction of the high-voltage side. When winding the lower section of the high-voltage coil, the lower section tap of the high-voltage coil is led out from the middle of the high-voltage side. End insulation is placed at the beginning and end of each layer of coil turns, and insulating material is added between layers. The winding of the lower section of the high-voltage coil is completed in sequence, and the tail of the high-voltage coil is led out from the middle of the high-voltage side.

[0011] On the other hand, the present invention also proposes a method for winding a transformer coil, comprising: After the high-voltage coil is wound, an insulating layer is wound on the outer surface of the high-voltage coil, and a low-voltage coil is wound on the outside of the insulating layer; wherein, the high-voltage coil is divided into upper and lower sections; When winding the upper section of the high-voltage coil, the beginning of the high-voltage coil is led out at the axial end of the high-voltage side, and after the upper section of the high-voltage coil is wound, the tap of the upper section of the high-voltage coil is led out from the axial middle of the high-voltage side. When winding the lower section of the high-voltage coil, the tap of the lower section of the high-voltage coil is led out from the middle of the high-voltage side, and after the lower section of the high-voltage coil is wound, the tail of the high-voltage coil is led out from the middle of the high-voltage side.

[0012] Furthermore, the high-voltage coil adopts a multi-layer cylindrical structure, with an upper pad provided outside the top insulation layer of the upper section of the high-voltage coil; a middle pad provided between the upper section and the lower section of the high-voltage coil; and a lower pad provided at the bottom of the lower section of the high-voltage coil.

[0013] Furthermore, several layers of axially connected heat dissipation channels are provided between the upper section and the lower section of the high-voltage coil. Before the high-voltage coil is wound, several layers of axially penetrating heat dissipation channels are set between the low-voltage coil and the high-voltage coil. Among these layers, one axially penetrating heat dissipation channel is used to place the end corner ring of the high-voltage coil.

[0014] Furthermore, when winding the upper section of the high-voltage coil, the beginning of the high-voltage coil is led out at the axial end of the high-voltage side, and end insulation is placed at the beginning and end of each layer of coil turns. Insulating material is added between layers. The upper section of the high-voltage coil is wound in sequence, and the tap of the upper section of the high-voltage coil is led out from the middle of the axial direction of the high-voltage side. When winding the lower section of the high-voltage coil, the lower section tap of the high-voltage coil is led out from the middle of the high-voltage side. End insulation is placed at the beginning and end of each layer of coil turns, and insulating material is added between layers. The winding of the lower section of the high-voltage coil is completed in sequence, and the tail of the high-voltage coil is led out from the middle of the high-voltage side.

[0015] On the other hand, the present invention also proposes a transformer, wherein the transformer uses a coil wound by the above-described transformer coil winding method.

[0016] The beneficial effects of this invention are as follows: When winding the upper section of the high-voltage coil, the beginning of the high-voltage coil is led out at the axial end of the high-voltage side, end insulation is placed at the beginning and end of each layer of coil, and insulating material is added between layers. The upper section of the high-voltage coil is wound in sequence, and the tap of the upper section of the high-voltage coil is led out from the axial middle of the high-voltage side. When winding the lower section of the high-voltage coil, the tap of the lower section of the high-voltage coil is led out from the axial middle of the high-voltage side, end insulation is placed at the beginning and end of each layer of coil, and insulating material is added between layers. The lower section of the high-voltage coil is wound in sequence, and the end of the high-voltage coil is led out from the axial middle of the high-voltage side. This not only eliminates the need for reversing when winding the high-voltage coil, avoiding the dismantling of equipment such as winding machines, molds, and wires, but also effectively shortens the length of the tap leads in the transformer, avoids the problem of not being able to fix the coil after the radial lead is led out, and also reduces the size of the transformer. Attached Figure Description

[0017] Figure 1 This is a schematic diagram of the winding of the high-voltage coil in a transformer in the prior art; Figure 2 This is a structural diagram of the transformer body and tap leads in the existing technology; Figure 3 This is a schematic diagram of the high-voltage coil winding method proposed in this invention in practical application; Figure 4 This is a schematic diagram of the coil after winding, in a practical application scenario, where a low-voltage coil is wound first and then a high-voltage coil, according to the transformer coil winding method proposed in this invention. Figure 5 This is a schematic diagram of another winding method for a high-voltage coil in the practical application of the transformer coil winding method proposed in this invention. Figure 6 This is a schematic diagram of the coil after winding, in a practical application scenario, where the transformer coil winding method proposed in this invention first winds the high-voltage coil and then winds the low-voltage coil. Figure 7 This is a schematic diagram of the structure of a transformer proposed in this invention; Figure 8 This is a schematic diagram of a transformer body and tap lead structure proposed in this invention; Figure 9 This is a schematic diagram of coil winding in a transformer according to the present invention; Figure 10 This is a low-voltage side wiring diagram of the first embodiment of a transformer proposed in this invention in a practical application scenario; Figure 11This is a low-voltage side wiring diagram of a second embodiment of a transformer proposed in this invention in a practical application scenario; Figure 12 This is a high-voltage side wiring diagram of the first embodiment of a transformer proposed in this invention in a practical application scenario; Figure 13 This is a high-voltage side wiring diagram of a second embodiment of a transformer proposed in this invention in a practical application scenario. Figure 14 This is a high-voltage side wiring diagram of a third embodiment of a transformer proposed in this invention in a practical application scenario; The image includes: 101-High voltage coil end corner ring; 102-Upper pad; 103-High voltage coil inner oil passage; 104-High voltage coil head; 105-High voltage coil end insulation; 106-High voltage coil upper section; 107-High voltage middle pad; 108-High voltage coil middle corner ring; 109-High voltage coil upper section tap outlet; 1010-High voltage coil lower section tap outlet; 1011-High voltage coil tail; 1012-High voltage coil lower section; 1013-Low voltage coil end insulation; 1014-Low voltage coil; 1015-Low voltage coil oil passage; 1016-Low voltage coil external oil passage strip; 1017-End corner ring oil passage; 1018-High voltage coil inner oil passage; 1019-High voltage coil lower pad; 1-Iron core; 2-Low voltage coil start; 3-Low voltage output terminal; 4-High voltage lead; 5-Low voltage coil end; 6-Upper clamp; 7-Clamp side beam; 8-Upper pressure plate; 9-Pull rod; 10-Coil; 11-Lower support plate; 12-Lower clamp; 13-Tap lead; 14-Tap switch; 15-Iron core pad. Detailed Implementation

[0018] To make the objectives, technical solutions, and advantages of the present invention clearer, the present invention will be further described in detail below with reference to the accompanying drawings and embodiments.

[0019] The inventive concept of this invention is to lead out the upper section tap head, the lower section tap head, and the tail head of the high-voltage coil in the middle of the high-voltage side axially, so that the coil does not need to be removed and rotated 180 degrees during the high-voltage coil winding process, thereby improving the winding efficiency. At the same time, there is no need to set a long tap lead for the coil in the transformer, avoiding the problems of difficulty in fixing and poor economy caused by excessively long tap leads.

[0020] Example 1 of transformer coil winding method: like Figure 3The diagram shown illustrates a high-voltage coil winding method proposed in this invention during practical application. When winding the upper section of the high-voltage coil, winding begins at the starting point A, proceeding from left to right. After completing the first layer, layers 2 through 14 are wound sequentially. Based on a predetermined number of turns for tapping out during the winding process, taps X6, X4, and X2 are connected on the 14th layer and axially led out from the center of the coil. After the upper section is completed, the coil does not need to be rotated 180° before starting the winding of the lower section.

[0021] When winding the lower section of the high-voltage coil, taps X7, X5, and X3 of the lower section of the high-voltage coil are led out from the middle of the high-voltage side. Connect taps X7, X5, and X3, and start winding from X7, winding from the left to the right. After completing the first layer of high-voltage coil winding, continue to increase the layers to complete the winding of the 2nd to 14th layers of wire. Lead out the tail X of the high-voltage coil from the middle of the high-voltage side.

[0022] Example 2 of transformer coil winding method: like Figure 4 The diagram shows a transformer coil winding method proposed in this invention, where a low-voltage coil is wound first, followed by a high-voltage coil, in a practical application scenario. Before winding the low-voltage coil 1014, insulating material is wound around its inner side to insulate the inner side. During winding, a low-voltage winding mold is used to control the inner diameter of the coil. An axially penetrating heat dissipation channel is formed inside the low-voltage coil 1014 via a low-voltage coil oil passage 1015 support. The low-voltage coil 1014 is formed by the coil... The conductor and the end insulation 1013 of the low-voltage coil are constituted; after the low-voltage coil 1014 is wound, the outer oil passage 1016 and the corner ring oil passage 1017 of the low-voltage coil are continued to be wound from the outer surface of the low-voltage coil 1014; L-shaped corner rings 101 (i.e., the end corner rings of the high-voltage coil) are placed at both ends of the corner ring oil passage 1017, and the inner oil passage 1018 of the high-voltage coil is wound inside the L-shaped corner ring 101 to separate the low-voltage coil 1014 and the high-voltage coil. At this time, the winding of the low-voltage coil 1014 and the winding of its outer surface insulation layer are completed.

[0023] The high-voltage coil is divided into upper and lower sections. When winding the upper section 106 of the high-voltage coil, the high-voltage coil starters 104 (A, B, C) are led out at the axial end of the high-voltage side. End insulation 105 (i.e., high-voltage coil end insulation) is placed at the beginning and end of each layer of coil. Insulating material is added between layers. The upper section 106 of the high-voltage coil is wound in sequence, and the high-voltage coil upper section taps 109 (X2, X4, and X6) are led out from the middle of the high-voltage side. When winding the lower section 1012 of the high-voltage coil, the high-voltage coil lower section taps 1010 (X3, X5, and X7) are led out from the middle of the high-voltage side. End insulation is placed at the beginning and end of each layer of coil. Insulating material is added between layers. The lower section 1012 of the high-voltage coil is wound in sequence, and the high-voltage coil tails 1011 (X, Y, Z) are led out from the middle of the high-voltage side. Meanwhile, high-voltage coil internal oil passages 103 are provided in both the upper and lower sections of the high-voltage coil; a high-voltage coil middle corner ring 108 is also provided between the upper and lower sections of the high-voltage coil.

[0024] The high-voltage coil adopts a multi-layer cylindrical structure. An upper pad 102 is provided outside the top insulation layer 105 (i.e., the high-voltage coil end insulation) of the upper section 106 of the high-voltage coil; a middle pad 107 is provided between the upper section 106 and the lower section 1012 of the high-voltage coil; and a lower pad 1019 is provided at the bottom of the lower section 1012 of the high-voltage coil.

[0025] Specific implementation method 3 for transformer coil winding: In the manufacturing process of transformer coils, a low-voltage winding mold is used to control the inner diameter of the coil to realize the winding of the low-voltage coil. Before winding the low-voltage coil, the inner insulation of the low-voltage coil is first wound with insulating material, and then the low-voltage coil is wound.

[0026] During the winding of the low-voltage coil: the axial end of the low-voltage coil is led out. The low-voltage coil is composed of coil wires and end insulation. An axially penetrating heat dissipation channel is set inside the low-voltage coil using oil channel support bars. The distribution position and number of oil channel support bars are set according to the transformer capacity and number of turns. The axial end of the low-voltage coil is led out.

[0027] After the low-voltage coil is wound: directly wind the external oil passage, corner ring oil passage, place the corner ring, and the inner oil passage of the high-voltage coil, and start winding the high-voltage coil to realize the integrated winding of high and low voltage coils and ensure the overall structural strength of the transformer coil.

[0028] Before the high-voltage coil is wound: Multiple axially continuous heat dissipation channels are designed between the low-voltage and high-voltage coils. These channels serve to dissipate heat from the outside of the low-voltage coil and the inside of the high-voltage coil, while also providing insulation between the low-voltage coils. One of the axially continuous heat dissipation channels houses the end rings of the high-voltage coil, reducing the electric field strength at the end of the high-voltage coil by adding these end rings. The high-voltage coil adopts a multi-layered cylindrical structure divided into upper and lower sections, with upper, middle, and lower pad end rings to reduce the electric field strength between layers and sections of the high-voltage coil, thus preventing partial discharge.

[0029] During the high-voltage coil winding: First, the upper section of the high-voltage coil is wound from left to right, with the first terminals A, B, and C led out at the axial end on the high-voltage side. Then, end insulation is placed at the beginning and end of each layer of turns, and insulating material is added between layers. This process is repeated to complete the upper section of the high-voltage coil. Tap joints X2, X4, and X6 are led out at the axial middle of the high-voltage side to avoid radial lead-out connections. Subsequent lead-out fixing measures are implemented to reduce the insulation distance between the transformer leads and the tank, thus reducing the transformer size. After the upper section is completed, the lower section of the high-voltage coil is wound from left to right, with tap joints X3, X4, and X5 led out at the axial middle of the high-voltage side. Then, end insulation is placed at the beginning and end of each layer of turns, and insulating material is added between layers. This process is repeated to complete the lower section of the high-voltage coil. The last terminals X, Y, and C are led out at the axial middle of the high-voltage side. The upper and lower sections of the transformer high-voltage coil are designed with multiple axially connected heat dissipation channels, which not only serve to dissipate heat inside the high-voltage coil but also achieve a uniform voltage gradient distribution and reduced electric field intensity throughout the coil. This solution avoids the drawback of existing transformers where, after the upper section of the high-voltage coil is wound, the coil needs to be removed, rotated 180 degrees, and then the lower section of the high-voltage coil needs to be wound.

[0030] By rationally distributing heat dissipation channels inside the low-voltage coil, between the high and low-voltage coils, and inside the high-voltage coil, the insulation and heat dissipation problems of existing transformer products can be solved.

[0031] Specific implementation method 4 for transformer coil winding: Meanwhile, another method for winding transformer coils proposed in this invention, such as... Figure 5 and Figure 6 As shown, after the high-voltage coil is wound, an insulating layer is wound on the outer surface of the high-voltage coil, and a low-voltage coil is wound on the outside of the insulating layer; wherein, the high-voltage coil is divided into upper and lower sections; When winding the upper section 106 of the high-voltage coil, the high-voltage coil heads 104 (A, B, C) are led out at the axial end of the high-voltage side, and after the upper section of the high-voltage coil is wound, the upper section tap 109 of the high-voltage coil is led out from the middle of the axial side.

[0032] When winding the lower section 1012 of the high-voltage coil, the tap 1010 of the lower section of the high-voltage coil is led out from the middle of the high-voltage side axially, and after the winding of the lower section of the high-voltage coil is completed, the tail end 1011 (X, Y, Z) of the high-voltage coil is led out from the middle of the high-voltage side axially.

[0033] Specifically: When winding the upper section 106 of the high-voltage coil, the high-voltage coil starter 104 is led out at the axial end of the high-voltage side. Insulation is placed at the beginning and end of each layer of turns, and insulating material is added between layers. This process is repeated to complete the winding of the upper section of the high-voltage coil. The high-voltage coil taps 109 (X2, X4, X6) are then led out from the axial center of the high-voltage side. When winding the lower section 1012 of the high-voltage coil, the high-voltage coil taps 1010 (X3, X5, X7) are led out from the axial center of the high-voltage side. Insulation is placed at the beginning and end of each layer of turns, and insulating material is added between layers. This process is repeated to complete the winding of the lower section of the high-voltage coil. The high-voltage coil tail is then led out from the axial center of the high-voltage side. Simultaneously, before winding the high-voltage coil, the inner oil passage 1018 of the high-voltage coil is wound first.

[0034] Specifically, the high-voltage coil adopts a multi-layer cylindrical structure. An upper pad 102 is provided outside the top insulation layer 105 (i.e., the high-voltage coil end insulation) of the upper section of the high-voltage coil; a middle pad 107 is provided between the upper and lower sections of the high-voltage coil; and a lower pad 1019 is provided at the bottom of the lower section of the high-voltage coil. Before the high-voltage coil is wound, several layers of axially penetrating heat dissipation channels are provided between the low-voltage coil and the high-voltage coil. Among these, one layer of axially penetrating heat dissipation channels is used to place the end corner ring of the high-voltage coil. Several layers of axially penetrating heat dissipation channels are provided between the upper and lower sections of the high-voltage coil. Simultaneously, an internal oil passage 103 is provided in both the upper and lower sections of the high-voltage coil; a middle corner ring 108 is also provided between the upper and lower sections of the high-voltage coil.

[0035] An insulating layer is wound on the outer surface of the high-voltage coil using the following method: After the high-voltage coil is wound, an angled ring oil channel 1017 is wound on the outer surface of the high-voltage coil, and L-shaped angled rings 101 are placed at both ends of the angled ring oil channel 1017, wherein the opening of the L-shaped angled rings faces the high-voltage coil; an outer oil channel 1016 for the low-voltage coil is wound outside the L-shaped angled rings; after the outer oil channel 1016 for the low-voltage coil is wound, a low-voltage coil 1014 is wound to separate the low-voltage coil and the high-voltage coil.

[0036] The low-voltage coil is wound using the following method: before winding the low-voltage coil 1014, insulating material is wound on the inside of the low-voltage coil to make the inside of the low-voltage coil insulated; during the winding of the low-voltage coil, a low-voltage winding mold is used to control the inner diameter of the coil; and an axially penetrating heat dissipation channel is set inside the low-voltage coil through the low-voltage coil oil passage 1015 support bar. The low-voltage coil 1014 is composed of coil wires and low-voltage coil end insulation 1013.

[0037] Transformer Specific Implementation Method 1: like Figures 7-9 As shown, the transformer uses the above-mentioned transformer coil winding method to obtain the set coil 10 (i.e., coil), and the low voltage coil head 2 and the low voltage output terminal 3 are led out from the upper front end of the transformer. At the same time, the low voltage coil tail 5 is also led out from the upper front end of the transformer; the high voltage coil leads 4 (A, B, C) are led out from the upper rear end of the transformer.

[0038] After the transformer coil is wound, an upper pressure plate 8 is placed between the transformer core 1 and the coil assembly 10, and a lower support plate 11 is placed at the bottom of the coil assembly 10. A non-metallic upper clamp 6 is installed on the upper pressure plate 8, parallel to the axis of the core 1. A clamping side beam 7 is set at the bottom of the core 1, perpendicular to the upper clamp 6. A tie rod 9 is vertically set between the upper pressure plate 8 and the lower support plate 11 to clamp the core 1 and the coil assembly 10 by fastening the tie rod 9 and the clamping side beam 7. A lower clamp 12 is also provided below the lower support plate 11, and a tap changer 14 is provided on the lower clamp 12. The tap changer 14 is connected to the decomposed head and tail of the high-voltage coil through a tap lead 13.

[0039] Iron yoke insulating pads 16 are provided between the rotating coil 10 and the upper pressure plate 8, and between the rotating coil 10 and the lower support plate 11.

[0040] Meanwhile, the transformer is fixed by the iron core pad 15.

[0041] Transformer Specific Implementation Method 2: like Figure 10-14 The diagram shown is a wiring diagram of a transformer in a practical application scenario. Figure 10 This is a Y-connection diagram for the low-voltage side of the transformer. Figure 11 This is the Yn-type wiring diagram for the low-voltage side of the transformer; Figure 12 This is a diagram of the Y-connection on the high-voltage side of the transformer. Figure 13 This is the Yn-type wiring diagram for the high-voltage side of the transformer; Figure 14 This is a delta connection diagram for the high-voltage side of a transformer. Different connection groups are formed by combining different connection methods on the low-voltage and high-voltage sides (e.g., Dyn-11; YD-11; YY-11, etc.).

[0042] Transformer Specific Implementation Method 3: After the coil is wound, a lower support plate is placed under the transformer core, and then the upper pressure plate and clamp are installed on the coil. The core and coil are clamped by tightening the tie rod and the side beam of the clamp. The side beam serves to tighten and limit the core and press the upper pressure plate, avoiding the problem of excessive clamping of the core and deformation of the clamp, and ensuring the short-circuit withstand capability of the transformer and coil.

[0043] After the high-voltage coil taps X2, X4, X6, X3, X5, and X7 are connected to the tap changer, the transformer voltage is adjusted. The transformer tap lead layout is standardized, and the transformer size is reduced by coordinating with the beginning and end of the low-voltage coil. This avoids the insulation problems between the tap leads and the beginning A, B, C, and the end X, Y, C.

[0044] The oil channels inside, outside, and at the end corner rings of the low-voltage coil are all connected by iron yoke insulating pads to achieve heat dissipation through a bottom-up flow channel. The oil channels inside and outside the high-voltage coil are connected by high-voltage oil channel pads and a pad in the middle of the high-voltage coil to form two sets of bottom-up flow channels for heat dissipation. The above measures solve the insulation and heat dissipation problems of existing transformer products.

[0045] In summary, the transformer coil winding method of this invention involves directly winding the insulation between the high and low voltage coils after the low-voltage coil is wound during the transformer coil manufacturing process. This achieves interlocking of the high and low voltage coils, increasing the mechanical strength of the coil. Simultaneously, the use of a lower support plate, upper pressure plate, and non-metallic clamps, tie rods, and side beams ensures the transformer and coil's short-circuit withstand capability, while avoiding insulation protection issues for the metal clamps caused by high and low voltage leads. This reduces metal component losses due to leakage flux and lowers transformer load losses. By adding corner rings to reduce the electric field strength at the high-voltage coil ends, a novel coil structure is proposed, achieving a uniform voltage gradient distribution and reduced electric field strength throughout the coil. Through a reasonable distribution and arrangement of the leads, standardized production is achieved while avoiding the need for commutation during coil winding, thus improving production efficiency. The reasonable distribution of heat dissipation channels within the high and low voltage coils, between the high and low voltage coils, and within the high-voltage coil solves the insulation and heat dissipation problems of existing transformer products. The above-mentioned transformer coil manufacturing technology and product structure address the shortcomings of existing transformers.

Claims

1. A method for winding a transformer coil, characterized in that, include: After the low-voltage coil is wound, an insulating layer is wound on the outer surface of the low-voltage coil, and a high-voltage coil is wound on the outside of the insulating layer; wherein, the high-voltage coil is divided into upper and lower sections; When winding the upper section of the high-voltage coil, the beginning of the high-voltage coil is led out at the axial end of the high-voltage side, and after the upper section of the high-voltage coil is wound, the tap of the upper section of the high-voltage coil is led out from the axial middle of the high-voltage side. When winding the lower section of the high-voltage coil, the tap of the lower section of the high-voltage coil is led out from the middle of the high-voltage side, and after the lower section of the high-voltage coil is wound, the tail of the high-voltage coil is led out from the middle of the high-voltage side.

2. The transformer coil winding method according to claim 1, characterized in that, The high-voltage coil adopts a multi-layer cylindrical structure, with an upper pad outside the top insulation layer of the upper section of the high-voltage coil; a middle pad between the upper and lower sections of the high-voltage coil; and a lower pad at the bottom of the lower section of the high-voltage coil.

3. The transformer coil winding method according to claim 2, characterized in that, Several layers of axially connected heat dissipation channels are provided between the upper section and the lower section of the high-voltage coil. Before the high-voltage coil is wound, several layers of axially penetrating heat dissipation channels are set between the low-voltage coil and the high-voltage coil. Among these layers, one axially penetrating heat dissipation channel is used to place the end corner ring of the high-voltage coil.

4. The method for winding a transformer coil according to any one of claims 1-3, characterized in that, When winding the upper section of the high-voltage coil, the beginning of the high-voltage coil is led out at the axial end of the high-voltage side. End insulation is placed at the beginning and end of each layer of coil turns, and insulating material is added between layers. The upper section of the high-voltage coil is wound in sequence, and the tap of the upper section of the high-voltage coil is led out from the middle of the axial direction of the high-voltage side. When winding the lower section of the high-voltage coil, the lower section tap of the high-voltage coil is led out from the middle of the high-voltage side. End insulation is placed at the beginning and end of each layer of coil turns, and insulating material is added between layers. The winding of the lower section of the high-voltage coil is completed in sequence, and the tail of the high-voltage coil is led out from the middle of the high-voltage side.

5. A method for winding a transformer coil, characterized in that, include: After the high-voltage coil is wound, an insulating layer is wound on the outer surface of the high-voltage coil, and a low-voltage coil is wound on the outside of the insulating layer; wherein, the high-voltage coil is divided into upper and lower sections; When winding the upper section of the high-voltage coil, the beginning of the high-voltage coil is led out at the axial end of the high-voltage side, and after the upper section of the high-voltage coil is wound, the tap of the upper section of the high-voltage coil is led out from the axial middle of the high-voltage side. When winding the lower section of the high-voltage coil, the tap of the lower section of the high-voltage coil is led out from the middle of the high-voltage side, and after the lower section of the high-voltage coil is wound, the tail of the high-voltage coil is led out from the middle of the high-voltage side.

6. The transformer coil winding method according to claim 5, characterized in that, The high-voltage coil adopts a multi-layer cylindrical structure, with an upper pad outside the top insulation layer of the upper section of the high-voltage coil; a middle pad between the upper and lower sections of the high-voltage coil; and a lower pad at the bottom of the lower section of the high-voltage coil.

7. The transformer coil winding method according to claim 6, characterized in that, Several layers of axially connected heat dissipation channels are provided between the upper section and the lower section of the high-voltage coil. Before the high-voltage coil is wound, several layers of axially penetrating heat dissipation channels are set between the low-voltage coil and the high-voltage coil. Among these layers, one axially penetrating heat dissipation channel is used to place the end corner ring of the high-voltage coil.

8. The method for winding a transformer coil according to any one of claims 5-7, characterized in that, When winding the upper section of the high-voltage coil, the beginning of the high-voltage coil is led out at the axial end of the high-voltage side. End insulation is placed at the beginning and end of each layer of coil turns, and insulating material is added between layers. The upper section of the high-voltage coil is wound in sequence, and the tap of the upper section of the high-voltage coil is led out from the middle of the axial direction of the high-voltage side. When winding the lower section of the high-voltage coil, the lower section tap of the high-voltage coil is led out from the middle of the high-voltage side. End insulation is placed at the beginning and end of each layer of coil turns, and insulating material is added between layers. The winding of the lower section of the high-voltage coil is completed in sequence, and the tail of the high-voltage coil is led out from the middle of the high-voltage side.

9. A transformer, characterized in that, The transformer includes a coil wound using the transformer coil winding method as described in any one of claims 1-4 or 5-8.

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