CN114300255B - High-voltage winding preparation method and high-voltage winding - Google Patents

Abstract

The application discloses a preparation method of a high-voltage winding, which comprises the following steps: step ①: the wire is wound circumferentially along the outer peripheral surface of the winding body to form a high-voltage coil, and a tap is formed in the wire winding process; step ②: placing the tap in a protection cavity of the tool connecting piece and connecting and fixing the tap with the tool connecting piece; step ③: the winding body wound with the high-voltage coil is taken as a body to be injected into a mould of an injection machine, and high-temperature vulcanized silicone rubber is injected at the periphery of the body to be injected, so that the high-temperature vulcanized silicone rubber coats the high-voltage coil and the winding body; step ④: and removing the tool connecting piece to obtain the high-voltage winding with the tap exposed out of the high-temperature vulcanized silicone rubber. The application also discloses a high-voltage winding of the dry-type transformer, which is manufactured by adopting the preparation method. The high-temperature vulcanized silicone rubber injection process provided by the application has the advantages that the high-voltage insulating layer is firmer, the mechanical property is higher, and the service life is longer.

Description

High-voltage winding preparation method and high-voltage winding

Technical Field

The application relates to the technical field of power transformers, in particular to a high-voltage winding and a preparation method thereof.

Background

Current transformers can be divided into: oil immersed transformer, dry transformer, gas transformer. The dry-type transformer has the advantages of oil free, fireproof, long service life, energy conservation, low noise, simple maintenance, safety, reliability and the like. The majority of dry transformers currently on the market are resin cast high voltage winding dry transformers and open dry transformers. Although the dry-type transformer has been developed greatly in recent 10 years, there are still problems of insulation cracking, poor heat conduction, severe operating environment and the like in operation.

Disclosure of Invention

Aiming at the defects of the prior art, one of the purposes of the application is to provide a high-voltage winding preparation method which can prepare the high-voltage winding, and the high-temperature vulcanized silicone rubber injection process ensures that a high-voltage insulating layer is firmer, the mechanical property is higher, and meanwhile, the high-voltage winding has better bonding property with a high-voltage coil and a winding body and longer service life.

In order to achieve the above purpose, the technical scheme adopted by the application is as follows: a preparation method of a high-voltage winding comprises the following steps:

step ①: the wire is wound circumferentially along the outer peripheral surface of the winding body to form a high-voltage coil, and a tap is formed in the wire winding process;

Step ②: placing the tap in a protection cavity of the tool connecting piece and connecting and fixing the tap with the tool connecting piece;

Step ③: and placing the winding body wound with the high-voltage coil into a mold of an injection machine as a body to be injected, and injecting high-temperature vulcanized silicone rubber at the periphery of the body to be injected, so that the high-temperature vulcanized silicone rubber coats the high-voltage coil and the winding body.

Step ④: and removing the tool connecting piece to obtain the high-voltage winding with the tap exposed out of the high-temperature vulcanized silicone rubber.

The method can prepare the high-voltage winding, and the high-temperature vulcanized silicone rubber injection process ensures that the high-voltage insulating layer is firmer, the mechanical property is higher, and meanwhile, the high-voltage winding has better bonding property with the high-voltage coil and the winding body and longer service life.

Preferably, the winding body includes a supporting bobbin and a winding part on an outer circumferential surface of the supporting bobbin, and the high voltage coil is formed by winding the wire on the winding part in step ①. The high-voltage coil is wound through the winding body, the winding of the lead is firmer, and the formed high-voltage coil structure has better mechanical strength and better heat dissipation capability.

Preferably, in step ①, the wire includes a first wire wound from the first end of the winding part to the middle of the winding part in the axial direction of the support cylinder and led out three taps, and a second wire wound from the middle of the winding part to the second end of the winding part in the axial direction of the support cylinder and led out three more taps. The tap finally forms a tap changer which can be used for regulating voltage of the dry-type transformer according to different operation conditions.

Preferably, in step ②, the protection cavity is a stepped hole, the tap is welded in the stepped hole, and the tap is fixedly connected to the stepped hole, so that the tap is prevented from being coated with silicone rubber during injection and cannot be used for wiring.

Preferably, the inner wall of the step hole is provided with threads, and before the step ③, the bolt is connected in the step hole, so that the silicon rubber can be prevented from filling the six step holes, and the situation that the six taps cannot be used for wiring after being coated by the silicon rubber is avoided.

Preferably, prior to step ①, the support tube, the wire wrap portion, are made of fiberglass impregnated epoxy. The support cylinder and the winding part are prepared separately, the material is the most saved, the cost can be saved, the glass fiber epoxy resin composite material is low in cost, light in weight and good in mechanical property, and meanwhile, the carbon emission amount in the production process of the composite material is low, and the composite material is greener, more environment-friendly and more excellent in performance.

Preferably, the winding part comprises a plurality of winding plates, and before step ①, the plurality of winding plates are uniformly distributed circumferentially and adhered and fixed on the outer circumferential surface of the supporting cylinder, and the uniformly distributed circumferentially and adhered winding plates enable the winding of the wires on the outer circumferential surface of the supporting cylinder to be firmer, so that the wires can be uniformly supported.

Preferably, before step ①, a plurality of winding grooves are formed on the winding plate, so that the winding plate forms a plurality of comb teeth. Coils can be arranged between two adjacent comb teeth on the winding plate, and the coils are wound on the comb-tooth-shaped winding plate, so that the winding plate is more stable and prevents coil channeling. Meanwhile, the wires are wound in each winding groove, high-voltage coils can be reasonably distributed, each section of coil is arranged at intervals, cake-type coils or multi-section layer-type coils can be formed, and the coil structure is balanced in stress and good in mechanical strength.

Preferably, in step ③, the high-temperature vulcanized silicone rubber coats the high-voltage coil and the winding body by integral vacuum injection and fills the gap between the high-voltage coil and the winding body and both ends of the winding body, thereby integrally improving the insulation performance and mechanical performance of the high-voltage winding.

The second object of the present application is to provide a high-voltage winding, which is manufactured by the method for manufacturing the high-voltage winding. The high-voltage winding has the advantages of good fireproof performance, low-temperature resistance, ageing resistance and short-circuit test resistance, excellent electrical insulation performance, energy conservation and environmental protection.

The beneficial effects of the application are as follows: compared with the prior art, the high-voltage winding preparation method can prepare the high-voltage winding, and the high-temperature vulcanized silicone rubber injection process ensures that the high-voltage insulating layer is firmer, the mechanical property is higher, and meanwhile, the high-voltage winding preparation method has better bonding property with the high-voltage coil and the winding body and longer service life; compared with liquid silicone rubber, the high-temperature vulcanized silicone rubber filler is uniformly dispersed, and partial discharge of the dry-type transformer caused by filler agglomeration is avoided, so that the overall performance of the dry-type transformer is better.

Drawings

Fig. 1 is a front view of a dry-type transformer 10 according to an embodiment of the present application;

fig. 2 is a top view of a dry-type transformer 10 according to an embodiment of the present application;

fig. 3 is a front view of an assembled core 110 according to an embodiment of the present application;

fig. 4 is an enlarged view at G in fig. 2;

FIG. 5 is a schematic perspective view of a coil 1310 according to an embodiment of the present application;

FIG. 6 is a cross-sectional view of a support cylinder 1311 in accordance with one embodiment of the application;

fig. 7 is a perspective view of a high voltage coil 1320 wound around a bobbin 1310 in accordance with an embodiment of the present application;

fig. 8 is a schematic perspective view of a high voltage winding 130 according to an embodiment of the present application;

Fig. 9 is a schematic perspective view of a tool connection 101 according to an embodiment of the application

FIG. 10 is a simplified electrical schematic of a high voltage coil 1320 in accordance with an embodiment of the application;

FIG. 11 is a partial cross-sectional view of a high voltage winding 130 according to an embodiment of the present application;

Fig. 12 is a partial cross-sectional view of a high voltage winding 230 of another embodiment of the present application;

fig. 13 is a partial cross-sectional view of a high voltage winding 330 of yet another embodiment of the present application;

fig. 14 is a partial cross-sectional view of a high voltage winding 430 of yet another embodiment of the present application.

Detailed Description

As required, specific embodiments of the present application will be disclosed herein. However, it is to be understood that the embodiments disclosed herein are merely exemplary of the application, which may be embodied in various forms. Therefore, specific details disclosed herein are not to be interpreted as limiting, but merely as a basis for the claims and as a representative basis for teaching one skilled in the art to variously employ the present application in virtually any appropriately manner, including employing the various features disclosed herein in connection with features that may not be explicitly disclosed.

The term "coupled" as used herein is to be interpreted broadly, unless explicitly stated or limited otherwise, as the term "coupled" as used herein, as defined in the context of the present application, as defined in the claims, and as the term "coupled" as used herein, as defined in the claims. In the description of the present application, it should be understood that the directions or positional relationships indicated by "upper", "lower", "end", "one end", etc., are based on the directions or positional relationships shown in the drawings, are merely for convenience of description and simplification of the description, and do not indicate or imply that the apparatus or element in question must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be construed as limiting the application.

As shown in fig. 1-3, the dry-type transformer 10 is a three-phase transformer, a-phase, B-phase and C-phase, respectively, i.e., the dry-type transformer 10 includes three single-phase transformers 100. The three transformers 100 may be arranged to form a linear or triangular structure according to the structure of the core 110, and the three transformers 100 are symmetrically constructed. The dry-type transformer 10 may be an isolation transformer, a variable frequency transformer, a test transformer, or the like.

In one embodiment, with continued reference to fig. 1-3, three transformers 100 are arranged in a linear configuration, and dry-type transformer 10 includes a core 110, three low voltage windings 120, and three high voltage windings 130. The iron core 110, the low voltage winding 120, and the high voltage winding 130 are sequentially arranged from inside to outside. The iron core 110 includes three columnar iron core bodies 111, an upper yoke 112 located at the upper ends of the three columnar iron core bodies 111, and a lower yoke 113 located at the lower ends of the three columnar iron core bodies 111, the three low-voltage windings 120 are respectively sleeved on the peripheries of the three columnar iron core bodies 111, and the three high-voltage windings 130 are respectively sleeved on the peripheries of the three low-voltage windings 120, i.e. the three columnar iron core bodies 111, the three low-voltage windings 120 and the three high-voltage windings 130 are sequentially sleeved one by one from inside to outside. The columnar iron core body 111 is formed by stacking a plurality of layers of silicon steel sheets, binding and fixing are performed on the plurality of layers of silicon steel sheets by using binding tapes, and the radial section of the columnar iron core body 111 is approximately elliptical or circular or other shapes, so long as the columnar iron core body can be accommodated in the hollow cavity of the low-voltage winding 120, and the columnar iron core body is not limited herein. The upper yoke 112 and the lower yoke 113 are also formed by stacking a plurality of silicon steel sheets, and the three columnar iron cores 111 are fixedly connected, thereby forming a three-phase iron core 110 as shown in fig. 3.

Illustratively, the present application provides a simple method of assembling the core 110, the low voltage winding 120, and the high voltage winding 130. The lower yoke 113 of the iron core 110 is formed by stacking multiple layers of silicon steel sheets and is arranged at the bottom of the dry-type transformer 10, then multiple layers of silicon steel sheets are respectively inserted into two ends and the middle part of the lower yoke 113 to form three columnar iron core bodies 111, then a low-voltage winding 120 and a high-voltage winding 130 are sequentially sleeved outside the columnar iron core bodies 111, finally multiple layers of silicon steel sheets are horizontally inserted into the upper ends of the three columnar iron core bodies 111 to form an upper yoke 112, and accordingly the assembly of the iron core 110, the low-voltage winding 120 and the high-voltage winding 130 is completed.

As shown in fig. 1 and 2, the iron core clamping member 140 is disposed on the outer side of the iron core 110, and the iron core clamping member 140 is formed into a channel-steel-like structure by connecting three clamping members, i.e., the iron core clamping member 140 is in a '匚' shape overall. Wherein the clamping member located at the intermediate position is disposed close to the core 110, and the other two clamping members are disposed toward a direction away from the core 110. Of course, in other embodiments, the core clamping member may be a rectangular hollow pipe, that is, the core clamping member is formed by mutually connecting and surrounding four clamping members with plate structures to form a closed structure, and the structure of the core clamping member is more stable; or the core clamps are interconnected by five, six or more plate structured clamps and are enclosed to form a closed structure, without limitation.

The number of the iron core clamping pieces 140 is four, wherein two iron core clamping pieces 140 are symmetrically positioned at two sides of the upper end of the iron core 110, and the upper end (namely the upper iron yoke 112) of the iron core 110 is clamped and then fixedly connected through a first fastener; the other two core clamping members 140 are symmetrically located at two sides of the lower end of the core 110, and are fixedly connected by a second fastening member after clamping the lower end of the core 110 (i.e., the lower yoke 113). The first fastener and the second fastener are respectively screw rods and bolts which are matched with each other to clamp the two ends of the iron core 110 through the two iron core clamping pieces 140. First through holes 141 are formed in two ends of the iron core clamping piece 140, the two iron core clamping pieces 140 are correspondingly placed on two sides of the upper end of the iron core 110, screws (not shown) are simultaneously arranged in the two first through holes 141 in the same end of the two iron core clamping pieces 140 in a penetrating mode, then the two iron core clamping pieces 140 are screwed and fixed through bolts, and two ends of the two iron core clamping pieces 140 are fixed in the mode that the two iron core clamping pieces 140 clamp the upper end of the iron core 110. The two core clamping members 140 at the lower end of the core 110 also fix and clamp the lower end of the core 110 in the same manner, which is not described in detail. In addition, to further reliably clamp the core 110, the middle portion of the core clamping member 140 also employs a plurality of screws and bolts that are used in cooperation with each other to clamp the middle portion of the core 110. The core clamping member 140 is further provided with a second through hole (not shown) for connection with the low voltage winding 120.

The core clip 140 is made of a fiber reinforced composite material, specifically, may be formed by compression molding with glass fiber impregnated epoxy resin, or may be formed by compression molding with aramid fiber impregnated epoxy resin, or may be formed integrally with other composite materials, which is not limited herein.

The fiber reinforced composite material refers to a composite material formed by winding, die pressing or pultrusion of a reinforcing fiber material, such as glass fiber, aramid fiber and the like, and a matrix material.

In other embodiments, the core clamping piece may be made of a metal material, may be an integrally formed channel steel, or may be connected and fixed by a welding manner after being formed separately. At this time, an insulating member such as a small post insulator is required to be attached to the outside of the core clip to insulate the high and low voltage wire from the metal channel. Meanwhile, an insulating pad is arranged outside the iron core, so that the iron core and the iron core clamping piece are insulated, and electromagnetic loss of the iron core caused by eddy current generated on the iron core clamping piece is avoided.

In this embodiment, compared with the core clamping piece of the traditional channel steel structure, the core clamping piece 140 made of the fiber reinforced composite material has more excellent economic performance, the insulating pad fixed on the outer surface of the core 110 can be omitted, the cost of the fiber reinforced composite material is lower, and the overall cost can be reduced by about 60%. Meanwhile, because the traditional channel steel structure is made of metal conductive materials, additional insulating components such as small post insulators are required to be connected to the iron core clamping pieces for insulation, so that on one hand, the cost is increased, on the other hand, the weight of the whole equipment is increased, the noise is large in the running process of the equipment, the carbon emission is large in the production process of iron products, the pollution is serious, and the iron core clamping pieces 140 made of fiber reinforced composite materials solve the problems; in addition, the core clip 140 made of the fiber reinforced composite material does not generate eddy current loss in the composite body, thereby reducing the no-load loss of the dry-type transformer 10. In summary, the iron core clamping piece 140 made of the fiber reinforced composite material has low cost, light weight and good mechanical property, and the carbon emission in the production process of the fiber reinforced composite material is low, and the iron core clamping piece is more green and environment-friendly.

As shown in fig. 2 and 4, the low voltage winding 120 includes a copper foil 121, a low voltage insulation layer 122, and a support bar 123, and the copper foil 121 and the low voltage insulation layer 122 are alternately arranged. Specifically, the copper foil 121 is wound and formed by a whole copper foil paper, and the low-voltage insulating layers 122 are wound together after being overlapped with the copper foil 121, so that the alternating arrangement of the copper foil 121 and the low-voltage insulating layers 122 is realized. At least one heat dissipation air passage is arranged in the low-voltage winding 120, and the heat dissipation air passage is positioned between the adjacent copper foil 121 and the low-voltage insulating layer 122, and a supporting bar 123 is positioned in the heat dissipation air passage and used for supporting and isolating the adjacent copper foil 121 and the low-voltage insulating layer 122. Specifically, the supporting strips 123 are insulating supporting strips 123, when the copper foil 121 and the low-voltage insulating layer 122 are overlapped and wound to a fixed thickness, the insulating supporting strips 123 are fixed on the outer surface of the low-voltage insulating layer 122 or the copper foil 121, and the overlapped and wound are continued so that the copper foil 121 or the low-voltage insulating layer 122 is closely attached to the insulating supporting strips 123, and the insulating supporting strips 123 can be fixed between the adjacent copper foil 121 and the low-voltage insulating layer 122 in an adhesive manner, or can be fixed by a pressing force generated during winding or other manners. A plurality of insulating support bars 123 are arranged in each layer of heat dissipation air passage, and the plurality of insulating support bars 123 are arranged at intervals along the circumferential direction of the outer circumferential surface of the copper foil 121 and play a role in supporting the adjacent copper foil 121 and the low-voltage insulating layer 122. At least two, three, four or more insulating support bars 123 are provided in each layer of heat dissipation air passages. Preferably, a plurality of insulating support bars 123 of the same layer are uniformly spaced along the circumferential direction of the outer circumferential surface of the copper foil 121. The copper foil 121 and the low voltage insulation layer 122 are continuously overlapped and wound to a predetermined thickness after the insulation support bar 123 is disposed to form the low voltage winding 120. The arrangement of the heat dissipation air passage can release heat generated by the low-voltage winding 120 in the operation process of the dry-type transformer 10, so as to avoid overheat failure of the dry-type transformer 10. The heat dissipation air passage may be provided with one layer, or may be provided with two or more layers, which is not limited herein.

The low-voltage insulating layer 122 is made of polyimide impregnated paper, specifically, SHS-P diphenyl ether prepreg, and is formed by impregnating a flexible composite material of polyimide film and polysulfone fiber non-woven fabric with diphenyl ether resin and baking, and of course, the low-voltage insulating layer can also be made of DMD insulating paper or silicone rubber film, or other insulating materials, and is selected according to different temperature rise grades of the dry-type transformer.

The insulating support bar 123 is made of glass fiber-impregnated epoxy resin or aramid fiber-impregnated epoxy resin, which is not limited herein. The insulating support bar 123 is a long bar with an i-shaped cross section, and has more stable mechanical strength. Of course, the insulating support bar may be a strip with a square cross section or other shapes, so long as the insulating support bar can play a role in supporting and isolating.

As shown in fig. 5-10, the high voltage winding 130 includes a winding body 1310, a high voltage coil 1320, and a high voltage insulation 1330, and a wire is wound on the winding body 1310 to form the high voltage coil 1320. Specifically, the winding body 1310 includes a support cylinder 1311 and a winding portion 1312, where the support cylinder 1311 is a hollow cylinder, may be a hollow elliptic cylinder, or may be other hollow cylindrical body; the winding portion 1312 is located on an outer peripheral surface of the support cylinder 1311, a wire is wound in the winding portion 1312 to form a high-voltage coil 1320, and the high-voltage coil 1320 includes a plurality of coils arranged at intervals in an axial direction of the support cylinder 1311.

Specifically, the winding portion 1312 includes a plurality of winding plates 1313, the plurality of winding plates 1313 being circumferentially uniformly distributed on the outer peripheral surface of the support cylinder 1311, each winding plate 1313 being axially disposed along the support cylinder 1311, the length of the winding plate 1313 along the axial direction of the support cylinder 1311 being smaller than the length of the support cylinder 1311 along the axial direction thereof. The number of the winding plates 1313 is at least two, that is, two, three, four or more, which is not limited herein. In order to make the winding of the wire firm and save the material as much as possible, the number of winding plates 1313 of the 10kV/1000kVA dry type transformer is set to twelve. In other embodiments, the length of the winding plate along the axial direction of the support cylinder may be equal to the length of the support cylinder along the axial direction thereof.

The winding plate 1313 is a rectangular plate, the longer side edge of the winding plate 1313 is arranged along the axial direction of the supporting cylinder 1311, a plurality of winding grooves 1314 are further formed in the winding plate 1313, the plurality of winding grooves 1314 are arranged along the radial direction of the supporting cylinder 1311 and are distributed at intervals along the axial direction of the supporting cylinder 1311, and the winding plate 1313 is in a comb shape, namely a plurality of comb teeth are formed on the winding plate 1313. The height of the comb teeth on the winding plate 1313 along the axial direction of the supporting cylinder 1311 is defined as tooth height, the tooth heights of the comb teeth at two ends of the winding plate 1313 and the tooth heights of the comb teeth at the middle part of the winding plate 1313 are larger than those of the comb teeth at other parts, because the field intensity at the end parts of the high-voltage coil 1320 is uneven, the tooth heights at two ends of the winding plate 1313 are set to be larger than a bit so as to uniformly apply an electric field, a tap for split wires needs to be led out at the middle part of the winding plate 1313, the tooth heights at the middle part of the winding plate 1313 are set to be larger than a bit, the distance between two corresponding adjacent winding grooves 1314 is larger, and a placing space can be reserved for the tap led out from the middle part of the winding plate 1313. Meanwhile, a comb tooth region with a slightly larger tooth height is defined as a high comb tooth region, and a comb tooth region with a slightly smaller tooth height is defined as a low comb tooth region. Then, by the above arrangement, the winding plate 1313 is made to form a first high comb-tooth region, a first low comb-tooth region, a second high comb-tooth region, a second low comb-tooth region, and a third high comb-tooth region in this order from one end toward the other end in the axial direction of the supporting cylinder 1311. Further, the tooth heights of the first high comb tooth region, the second high comb tooth region, and the third high comb tooth region are not particularly limited, and may be, for example, the same as each other or may be different from each other. And the first high comb tooth region and the third high comb tooth region can be symmetrically arranged about the second high comb tooth region, and the first low comb tooth region and the second low comb tooth region can also be symmetrically arranged about the second high comb tooth region. Of course, an asymmetric arrangement is also possible, without limitation.

At least one section of coil is arranged between two adjacent comb teeth on the winding plate 1313, so that wires are wound in each winding slot 1314, high-voltage coils 1320 are reasonably distributed and arranged, and the sections of coils are arranged at intervals.

When a plurality of winding plates 1313 are circumferentially and uniformly distributed on the outer circumferential surface of the supporting cylinder 1311, two ends of all the winding plates 1313 are flush, winding grooves 1314 on all the winding plates 1313 are matched in a one-to-one correspondence manner in the circumferential direction of the supporting cylinder 1311, each section of coil is wound in a circle of corresponding winding grooves 1314 on all the winding plates 1313 along the circumferential direction of the supporting cylinder 1311 by a lead, and the winding machine is balanced in stress and good in mechanical strength.

In other embodiments, in order to make the setting position of the tap clear, the plurality of winding plates may be fixed on the outer circumferential surface of the supporting cylinder in an unevenly setting manner, that is, the distance between two adjacent winding plates is unequal, for example, the distance between two adjacent winding plates is greater than the distance between any two other winding plates, at this time, each tap is led out from between the two adjacent winding plates, so that the tooth height of the comb teeth in the middle of the winding plates does not need to be set greater, and the setting position of each tap can be also set aside.

In other embodiments, the coil plate may also be an annular disk disposed circumferentially around the support cylinder. The plurality of winding plates are arranged at intervals along the axial direction of the supporting cylinder, and the wire is wound in the groove formed by two adjacent winding plates.

The support cylinder 1311 is a hollow tube formed by winding, solidifying, or pultrusion glass fiber impregnated epoxy resin, a hollow tube formed by winding, extruding, or winding glass fiber or aramid fiber impregnated epoxy resin, a hollow tube formed by winding, solidifying, or pultrusion aramid fiber impregnated epoxy resin, or a hollow tube formed by adopting other composite materials, which is not limited herein.

In an application scenario, the support cylinder 1311 and the winding plate 1313 are adhered and fixed after being formed separately. Specifically, the winding plate 1313 is also made of glass fiber impregnated epoxy resin, a certain thickness is formed by overlapping a plurality of layers of glass fiber cloth impregnated with epoxy resin, a rectangular glass fiber reinforced plastic plate is formed by compression molding and solidification, a winding groove 1314 is formed in the glass fiber reinforced plastic plate, and the winding groove 1314 is formed by turning, so that the winding plate 1313 is formed, and the winding plate 1313 is fixedly connected to the outer peripheral surface of the supporting cylinder 1311 through an adhesive, so that the material is most saved, and the cost can be saved. The adhesive is a bi-component high temperature resistant epoxy adhesive, but may be other adhesives, which is required to ensure that the supporting cylinder 1311 and the winding plate 1313 are firmly bonded, and is high temperature resistant, so as to adapt to high temperature injection of the high voltage insulating layer 1330 outside the winding body 1310.

In this embodiment, the winding plate 1313 is molded by compression molding and curing, and in other embodiments, the comb-shaped winding plate may be molded directly by integral casting and curing, so that the process is simplified, and the material of the winding plate is consistent with the foregoing, and will not be described again.

In another application scenario, the support cylinder 1311 is integrally formed with the winding plate 1313. The supporting cylinder 1311 and the winding plate 1313 are formed by impregnating glass fiber or aramid fiber with epoxy resin, pulling and extruding or winding the hollow tube with a large thickness, and then turning the hollow tube, so that the materials are wasted, but the strength between the supporting cylinder 1311 and the winding plate 1313 can be ensured, and the connection between the supporting cylinder 1311 and the winding plate 1313 is prevented from being damaged due to the fact that the bonding is not firm or in the process of injecting the high-voltage insulating layer 1330 later.

In yet another application scenario, as shown in fig. 5 and 6, the winding body 1310 further includes two flanges 1315, specifically, the flanges 1315 are located at two ends of the supporting cylinder 1311 and extend outwards along the radial direction of the supporting cylinder 1311 to form an annular disc surface, the flanges 1315 at two ends are oppositely disposed, when the winding plate 1313 is disposed on the outer peripheral surface of the winding body 1310, the outer end surfaces of the two ends of the winding plate 1313 abut against the disc surfaces where the two flanges 1315 face each other, so as to prevent the winding plate 1313 from being damaged due to a larger injection pressure in the process of injecting the high-voltage insulating layer 1330. Of course, the outer end surfaces of the two end portions of the winding plate 1313 may not abut against the disk surfaces facing each other with the two flanges 1315, that is, a gap may be left between the outer end surfaces of the two end portions of the winding plate 1313 and the disk surfaces facing the winding plate 1313 with the flanges 1315, which is not limited herein.

The flange 1315 is made of glass fiber impregnated epoxy resin, and is integrally formed with the support cylinder 1311, i.e. is formed by pultrusion or winding of glass fiber or aramid fiber impregnated epoxy resin, and then is processed and polished into a disc member with a certain thickness.

In other embodiments, the winding body may include only a winding portion, in which the winding portion is disposed circumferentially inside the high-voltage winding, without providing the rigid insulating liner, that is, without providing the support tube, and the wire is wound outside the winding portion to form the high-voltage coil, and the high-voltage insulating layer wraps the high-voltage coil and the winding portion. The high-voltage winding omits the structure of the rigid insulating lining cylinder, so that the heat conduction effect is better, and the interface between the high-voltage insulating layer and the rigid insulating lining cylinder is eliminated, thereby inhibiting the surface discharge of the rigid insulating lining cylinder, saving materials and reducing the cost.

The winding body 1310 is made of the fiber reinforced composite material, has the characteristics of light weight and high strength, ensures that the winding body 1310 has better mechanical strength, can effectively support winding of a wire, is not easy to damage, and avoids the wire from being scattered and shifted by injection impact force generated when high-temperature vulcanized silicone rubber is injected outside the winding body 1310; and the fiber reinforced composite material has good heat resistance, so that the winding body 1310 is prevented from being deformed due to excessive heat generated by the high-voltage coil 1320 in the operation process of the dry-type transformer 10.

Referring to fig. 5, 7 and 8, taking the a-phase transformer 100 as an example, a wire is wound around the outer circumferential surface of the winding body 1310 to form a high-voltage coil 1320. Specifically, the wire is wound in the winding slot 1314 of the winding portion 1312, such that the high-voltage coils 1320 are spaced apart in the axial direction of the supporting cylinder 1311, and the wire forms two external connections, namely, a first external connection D and a second external connection X, after the winding is completed, respectively, the first external connection D is used for connecting a cable, and the second external connection X is used for connecting other external connections, such as in a three-phase transformer, for interconnection with each phase change transformer. And, the wire is led out of six taps, respectively tap 2, tap 3, tap 4, tap 5, tap 6 and tap 7, at the middle of the wire body 1310 in the axial direction thereof, the six taps forming tap switches, and tap 2, tap 4 and tap 6 are defined as a first tap switch and tap 3, tap 5 and tap 7 are defined as a second tap switch for convenience of description.

In an application scenario, as shown in fig. 5, 7 and 10, the wires include a first wire and a second wire, where the first wire and the second wire are continuous wires, and the first wire and the second wire are covered with an insulating layer, and the insulating layer may be a polyimide film or a glass fiber film, or the insulating layer may be another insulating material such as polyester paint, or may be a combination of multiple insulating materials, which is not limited herein. The first wire is wound from one end of the winding portion 1312 to the middle of the winding portion 1312 in the axial direction of the support cylinder 1311, and three taps are led out. For convenience of description, the upper end of the winding portion 1312 is defined as a first end, the lower end of the winding portion 1312 is defined as a second end, the first wire is wound from the first end of the winding portion 1312 to the second end of the winding portion 1312, and the first wire is wound in a corresponding turn of the first winding slot 1314 on all the winding plates 1313 to form a first coil 1321, the first coil 1321 is a pancake winding method, and only one pancake coil is disposed in each winding slot 1314, and at this time, only one pancake coil is disposed in each section of coil. The first wire is located at the inner turn wire end of the first end of the winding portion 1312 to form a first external connection D exposed outside the high voltage insulation layer 1330, that is, the first external connection D is led out at the inner turn wire end of the first section coil 1321 (i.e., the head end of the first wire), the outer turn wire end of the first section coil 1321 extends to a corresponding turn of the second winding slot 1314 on all winding plates 1313 to form a second section coil 1322, and so on until the first wire is wound to the middle of the winding body 1310, and three taps, that is, tap 6, tap 4 and tap 2 as shown in fig. 10, are led out through the outer turn wire ends of the three sections of coils, respectively, so that the first wire is wound.

The second wire is wound from the middle of the winding portion 1312 to the second end of the winding portion 1312 in the axial direction of the support cylinder 1311, and is led out of the other three taps. Specifically, the second wire starts winding in the next winding slot 1314 adjacent to the tap 2, forming the third segment coil 1323, continues to wind toward the second end of the winding portion 1312 in the same winding manner as the first wire, and three further taps, i.e., tap 3, tap 5 and tap 7, are respectively led out from the three segments of coils starting from the third segment coil 1323 until the second wire winds to the corresponding one of the last winding slots 1314 on each winding plate 1313 at the second end of the winding portion 1312 and forms the terminal segment coil 1324. The outer turn wire end of the second wire at the second end of the winding portion 1312 forms a second external connection X exposed to the outside of the high voltage insulation 1330, that is, the second external connection X is led out at the outer turn wire end of the terminal section coil 1324 (i.e., the end of the second wire), so that the second wire is wound.

When the wire is wound, the corresponding winding grooves 1314 on all the winding plates 1313 are wound, so that each section of coil formed by winding the wire is perpendicular to the axial direction of the supporting cylinder 1311, the winding is convenient, the wire arrangement is neat, the winding plates 1313 and the supporting cylinder 1311 are uniformly stressed, and the mechanical strength is good.

In this way, the pancake type high-voltage coil 1320 is formed, and the coil structure has better mechanical strength, strong bearing capacity for electromotive force generated by short-circuit current, and better heat dissipation capacity compared with the layered coil with more pancake numbers. In addition, in the axial direction of the support cylinder 1311, as shown in fig. 8 and 10, the tap 6, the tap 4, and the tap 2 are sequentially distributed to form a first tap changer, the tap 3, the tap 5, and the tap 7 are sequentially distributed to form a second tap changer, and the first tap changer and the second tap changer are arranged in parallel, and the six taps form tapping devices of the high-voltage coil 1320 for the dry-type transformer 10 to adjust voltages according to different operation conditions.

The high-voltage coil 1320 is formed by winding a wire around the winding body 1310, and thus the high-voltage coil 1320 is annular, and the annular width of the high-voltage coil 1320 is defined as the width of the high-voltage coil 1320, so that the widths of the high-voltage coil 1320 on each radial section are uniform, that is, the outer side surface of the high-voltage coil 1320 is equidistant from the outer peripheral surface of the supporting cylinder 1311, so that the whole high-voltage coil 1320 is in stress balance. Of course, the widths of the coils in the radial cross section may not be exactly the same in consideration of actual operation, and may be substantially the same.

In the present embodiment, the second wire is wound from the next winding slot 1314 adjacent to the tap 2 to the last winding slot 1314 of the second end of the winding portion 1312, and in other embodiments, the second wire may be wound from the last winding slot of the second end of the winding portion up to the next winding slot adjacent to the tap 2, except that the second external X is formed first, and then the tap 7, the tap 5, and the tap 3 are sequentially formed. Of course, the winding method of the high-voltage coil 1320 is not limited to the above, and a pancake coil or a layer coil may be formed in other ways as long as the high-voltage winding 130 can be finally formed.

In this embodiment, the tap changer includes six taps, and the dry-type transformer 10 has five gear-stage adjustable voltages at this time, and in other embodiments, the tap changer may also include four taps, that is, the first tap changer and the second tap changer include two taps, respectively, and the dry-type transformer includes three gear-stage adjustable voltages at this time, so long as the actual use requirements of the dry-type transformer are met, and the present invention is not limited thereto.

As shown in fig. 7-9, the high voltage winding 130 is formed by wrapping the high voltage coil 1320 and the winding body 1310 with the high voltage insulation 1330. The high-voltage insulating layer 1330 is made of high-temperature vulcanized silicone rubber, specifically, a wire is wound on a winding body 1310 to form a high-voltage coil 1320, the winding body 1310 and the high-voltage coil 1320 are used as a body to be injected, the body to be injected is placed into a mold of an injection machine, and the high-temperature vulcanized silicone rubber is integrally injected on the periphery of the body to be injected by adding silicone rubber raw materials, so that the high-voltage winding 130 is obtained. The high-voltage insulating layer 1330 adopts high-temperature vulcanized silicone rubber, so that the insulating performance and mechanical performance of the high-voltage winding 130 are integrally improved.

After the high-temperature vulcanized silicone rubber is injected in a vacuum manner to cover the high-voltage coil 1320 and the winding body 1310, the high-temperature vulcanized silicone rubber fills the gap between the high-voltage coil 1320 and the winding body 1310 and covers the two ends of the winding body 1310, and the high-temperature vulcanized silicone rubber does not cover the inner wall of the supporting cylinder 1311, so that the high-voltage winding 130 is in a hollow column shape as a whole, and can be a hollow cylinder, a hollow elliptic cylinder or other hollow column bodies.

Before the high-temperature vulcanized silicone rubber is integrally injected, six taps are connected through the tooling connecting piece 101, so that the situation that the six taps are also coated by the silicone rubber in the injection process and cannot be used for wiring is avoided. As shown in fig. 9, the tool connection piece 101 is an aluminum alloy plate, a protection cavity is arranged on the plate surface of the tool connection piece 101, and the tap connection is fixed in the protection cavity. In the application, the protection cavity is six same step holes 1011, and the inner wall of the step holes 1011 is also provided with threads. The six taps are connected to the six stepped holes 1011, respectively, by welding, or by other means, without limitation. In addition, six step holes 1011 on the tool connecting piece 101 are arranged in two rows in parallel, and three step holes 1011 are arranged in each row so that the first tapping switch and the second tapping switch are also arranged in parallel. Meanwhile, before integral injection, after six taps are respectively connected to the six step holes 1011, bolts are connected in the six step holes 1011, so that the bolts can directly fill the residual space of the step holes 1011, the silicon rubber is prevented from filling the six step holes 1011, and the situation that the six taps cannot be used for wiring after being coated by the silicon rubber is avoided.

Two opposite sides of the tool connecting piece 101 are also provided with two symmetrical connecting grooves 1012, two connecting blocks are correspondingly arranged in the injection mold, and when the tool connecting piece 101 is placed in the injection mold, the tool connecting piece 101 is fixedly arranged in the injection mold through the two connecting grooves 1012 on the tool connecting piece and the two connecting blocks on the injection mold in a clamping manner, so that the tool connecting piece 101 is prevented from being offset due to large injection pressure in the process of injecting the silicone rubber.

In other embodiments, two symmetrical connecting blocks are arranged on two opposite sides of the tool connecting piece, two connecting grooves are correspondingly arranged in the injection mold, and when the tool connecting piece is placed in the injection mold, the tool connecting piece is respectively clamped and connected with the two connecting grooves on the injection mold through the two connecting blocks on the tool connecting piece, so that the tool connecting piece is fixed in the injection mold, and the tool connecting piece is prevented from being deviated due to larger injection pressure in the process of injecting the silicone rubber. After the high voltage insulating layer 1330 is formed by integral injection, the side surface of the tool connection piece 101 is coated with a small amount of silicone rubber, and since the silicone rubber coated on the tool connection piece 101 is relatively small, the tool connection piece 101 can be directly removed by a tool, exposing the first tap changer and the second tap changer, and finally forming the high voltage winding 130 as shown in fig. 8.

In this embodiment, the tool connecting pieces 101 are set to one, in other embodiments, two tool connecting pieces may be set, the tool connecting pieces at this time are smaller in size, three step holes are formed in each tool connecting piece, and six taps are connected to the six step holes, which is not limited herein.

In this embodiment, as shown in fig. 11, the high-voltage winding 130 covered with the high-voltage insulating layer 1330 is partially cut along the axial direction thereof, and the wire is wound around the comb-shaped winding plate 1313 by the above-described winding method to form the pancake high-voltage coil 1320, and the pancake high-voltage coil 1320 is spaced from the comb teeth of the winding plate 1313 along the axial direction of the high-voltage winding 130, that is, a pancake coil is provided between two adjacent comb teeth.

In another embodiment, as shown in fig. 12, which is a partial sectional view of the high voltage winding 230 coated with the high voltage insulation layer 2330, the wire is wound on the comb-shaped winding plate 2313 by a double winding continuous winding method to form the high voltage coil 2320. After two identical continuous wires are adjacently arranged, winding is started from a circle of winding grooves 2314 corresponding to the upper ends of all winding plates 2313 at the same time, a first section of coil 2321 is formed, the first section of coil 2321 comprises two coils closely arranged along the axial direction of the supporting cylinder 2311, a specific winding method is consistent with the high-voltage coil 1320, and the like, winding is performed downwards in a similar manner, other coils such as a second section of coil 2322 are continuously formed until the high-voltage coil 2320 arranged at intervals along the axial direction of the high-voltage winding 230 is formed, each section of coil comprises two coils closely arranged, the length of each section of coil along the axial direction of the winding plates 2313 is equal to the sum of the widths of two parallel wires along the axial direction of the supporting cylinder 2311, namely, two coils are arranged between two adjacent comb teeth on the winding plates 2313. The same two wires refer to the two wires with the same size and material. Compared with the continuous winding structure of a single wire (i.e., the structure of the high-voltage coil 1320), in the high-voltage winding with the same size specification, the number of the winding slots 2314 can be reduced, thereby reducing the wire transition section between the interval sections of each section of coil, reducing the consumption of wires and achieving the purpose of reducing the cost. In other embodiments, three pancake coils or more pancake coils can also be provided between adjacent two comb teeth on the winding plate.

In still another embodiment, as shown in fig. 13, which is a partial sectional view of the high-voltage winding 330 coated with the high-voltage insulating layer 3330 along the axial direction thereof, the width of the winding groove 3314 on the winding plate 3313 along the axial direction of the support cylinder 3311 is larger than the width of the winding groove 2314 on the winding plate 2313 along the axial direction of the support cylinder 2311. The first section of coil 3321 is formed by a layer winding method, specifically, a continuous wire is adopted, in a circle of first winding grooves 3314 corresponding to the upper ends of all winding plates 3313, continuous winding is carried out downwards along the axial direction of the support barrel 3311 at the upper end in the first winding grooves 3314 until the wire is wound to the lower end of the first winding grooves 3314, a first layer of coil is formed, the wire of the first layer of coil is in a tightly arranged spiral shape on the outer peripheral surface of the support barrel 3311, after the wire finishes the winding of the first layer of coil, a second layer of coil is continuously wound upwards along the axial direction of the support barrel 3311 from the lower end of the first winding grooves 3314, and the like, repeatedly winding is carried out until the first section of coil 3321 reaches a preset width of the high-voltage coil 3320 in the radial direction of the support barrel 3311, and finally the first section of coil 3321 is in a tightly arranged spiral shape on the outer peripheral surface of the support barrel 3311. Then, the wire is transferred to the second winding slot 3314 through the teeth of the winding plate 3313, and the second section of coil 3322 is continuously wound by the layer winding method, and the winding is continuously performed by analogy until the winding of the wires in all the winding slots 3314 is completed, thereby finally forming the high-voltage coil 3320.

Because the width of the winding groove 3314 along the axial direction of the support tube 3311 is larger, each section of coil is spirally arranged along the axial direction of the winding plate 3313, and the length of each section of coil along the axial direction of the winding plate 3313 is larger than the sum of the widths of two parallel wires, so that a multi-section cylindrical high-voltage coil 3320 is formed, compared with a pancake type structure (namely the structure of the high-voltage coil 2320) wound by adopting a double-winding continuous winding method, the high-voltage coil 3320 is more compact in the high-voltage winding with the same specification, the number of the winding grooves 3314 is fewer, the consumption of wires is also fewer, and the purpose of reducing the cost is further achieved.

In the present embodiment, the coil plate 3313 is provided to space the first coil 3321 and the second coil 3322 with the comb teeth therebetween, and in other embodiments, the coil plate may not be provided, and a gap may be left between the first coil and the second coil, and finally the high-voltage coil may be fixed by filling the high-voltage insulating layer, thereby achieving the purpose of insulating the high-voltage coil sections.

In another embodiment, as shown in fig. 14, a partial sectional view of the high-voltage winding 430 coated with the high-voltage insulating layer 4330 is taken along the axial direction thereof, and the formation mode of the high-voltage coil 4320 is identical to that of the high-voltage coil 3320 described above, and will not be repeated. But the length of each section of the high-voltage coil 4320 along the axial direction of the support cylinder 4311 is longer than the length of each section of the high-voltage coil 3320 along the axial direction of the support cylinder 3311, and the number of sections of the high-voltage coil 4320 is smaller in the dry type transformer 10 of the same voltage class. Since the length of each coil of the high-voltage coil 4320 along the axial direction of the support cylinder 4311 is greater, the voltage difference between each coil is greater, and thus an insulating layer needs to be added between layers of each coil to reduce the voltage difference, at this time, each coil is provided with an interlayer insulating layer 4301 along the axial direction of the high-voltage winding 430, so as to prevent the intensity of an interlayer electric field from being higher than the tolerance critical value of the insulating wire coating insulating film. And the layered structure in each section of coil has good lightning impulse resistance and obvious economic advantage. Specifically, when the wire is wound to a certain thickness by the layer winding method, the interlayer insulating layer 4301 is placed at a corresponding position and then the wire is continuously wound, so that the interlayer insulating layer 4301 can be provided in each coil.

The interlayer insulating layer 4301 may be a mesh cloth, insulating stays circumferentially spaced apart, or other hard insulating materials. The insulating stay is an insulating strip with wavy edges, so that the insulating stay is prevented from being damaged due to extremely high injection pressure when high-temperature vulcanized silicone rubber is injected to form a high-voltage insulating layer. And the insulating support bar is made of hard insulating materials, so that the impact force of high-temperature injection of the silicon rubber can be resisted. Meanwhile, the interlayer insulating layer 4301 may be provided as one layer, or may be provided as two or three layers, depending on different design conditions, and is not limited thereto.

In another embodiment, in conjunction with fig. 1-11, a method of manufacturing a high voltage winding 130 is provided, comprising the steps of:

Step ①: the wire is wound circumferentially around the outer circumference of the bobbin 1310 to form a high voltage coil 1320, and taps are formed during the wire winding process.

First, the winding body 1310 includes a supporting cylinder 1311 and a winding portion 1312 located on an outer peripheral surface of the supporting cylinder 1311, wherein the supporting cylinder 1311 is a hollow cylinder, may be a hollow elliptic cylinder, or may be other hollow cylindrical bodies; the winding portion 1312 includes a plurality of winding plates 1313, and the plurality of winding plates 1313 are disposed along the axial direction of the support cylinder 1311 and circumferentially distributed on the outer circumferential surface of the support cylinder 1311, and the number of the winding plates 1313 is at least two, that is, two, three, four or more, which is not limited herein. In order to make the winding of the wire firm and save the material as much as possible, the number of winding plates 1313 of the 10kV/1000kVA dry type transformer is set to twelve. The winding plate 1313 is further provided with a plurality of winding grooves 1314, and the plurality of winding grooves 1314 are arranged along the radial direction of the supporting cylinder 1311 and are distributed at intervals along the axial direction of the supporting cylinder 1311, so that the winding plate 1313 is comb-shaped.

The specific structure, materials, molding methods, etc. of the support cylinder 1311 and the winding plate 1313 are as described above, and will not be described again.

Next, the coil body 1310 is wound around the winding device, and the high-voltage coil 1320 is formed by winding a wire around the coil body 1310, and the high-voltage coil 1320 is arranged at intervals in the axial direction of the support cylinder 1311, thereby forming a pancake-type high-voltage coil 1320. The wire winding and the structure of the high voltage coil 1320 are the same as described above and will not be described again. And the wires are led out of the tap 2, the tap 3, the tap 4, the tap 5, the tap 6 and the tap 7 during winding, respectively, thereby forming a tap switch.

In this embodiment, the conductive wire is wound to form the pancake type high-voltage coil 1320, and in other manners, the conductive wire may be wound to form the double winding continuous type high-voltage coil 2320, the multi-segment cylindrical high-voltage coil 3320 and the segmented cylindrical high-voltage coil 4320 as shown in fig. 12-14, which are not described in detail. Furthermore, the tap changer may also include only four taps, which is not limiting here.

Step ②: the tap is placed in the protection cavity of the tool connection 101 and is fixedly connected with the tool connection 101.

The six taps are respectively connected and fixed to the protection cavity of the tool connector 101 through the tool connector 101 shown in fig. 9, and in the present application, the protection cavity is six stepped holes 1011, which can be connected by welding or by other fixing methods, which is not limited herein.

Step ③: the bobbin 1310 wound with the high-voltage coil 1320 is placed as a body to be injected into a mold of an injection machine, and high-temperature vulcanized silicone rubber is injected at the outer periphery of the body to be injected, so that the high-temperature vulcanized silicone rubber covers the high-voltage coil 1320 and the bobbin 1310.

Before this step, all connect the bolt in six step holes 1011 of frock connecting piece 101, so, the bolt can directly fill step hole 1011 surplus space, prevents that silicon rubber from filling six step holes 1011 to can avoid six taps to be used for the wiring after being covered by silicon rubber.

The winding body 1310 and the high-voltage coil 1320 connected with the tool connecting piece 101 are taken as a body to be injected, then after the periphery of the body to be injected is coated with a coupling agent, the body to be injected is put into a die of an injection machine, a silicon rubber raw material is added, high-temperature vulcanized silicon rubber is integrally injected at the periphery of the body to be injected, the high-voltage winding 130 is obtained after cooling, and the high-voltage insulating layer 1330 of the high-temperature vulcanized silicon rubber integrally improves the insulating property and the mechanical property of the high-voltage winding 130.

Two opposite sides of the tool connecting piece 101 are also provided with two symmetrical connecting grooves 1012, two connecting blocks are correspondingly arranged in the injection mold, when a body to be injected is placed in the mold of the injection machine, the tool connecting piece 101 is fixed in the injection mold by clamping and connecting the two connecting grooves 1012 on the tool connecting piece 101 with the two connecting blocks on the injection mold respectively, and the position of the tool connecting piece 101 is prevented from being deviated due to larger injection pressure in the process of injecting the silicone rubber. Of course, two symmetrical connecting blocks are arranged on two opposite side surfaces of the tool connecting piece, two connecting grooves are correspondingly arranged in the injection mold, and the tool connecting piece is connected with the connecting grooves of the injection mold in a matched manner, so that details are not repeated.

After the high-temperature vulcanized silicone rubber is coated on the high-voltage coil 1320 and the winding body 1310 by integral vacuum injection, the high-temperature vulcanized silicone rubber fills the gap between the high-voltage coil 1320 and the winding body 1310 and the two ends of the winding body 1310, and the high-temperature vulcanized silicone rubber does not coat the inner wall of the supporting cylinder 1311, so that the high-voltage winding 130 is in a hollow column shape as a whole, and can be a hollow cylinder, a hollow elliptic cylinder or other hollow column bodies.

Step ④: the tooling connection 101 is removed to obtain a high voltage winding 130 with taps exposed to the outside of the high temperature vulcanized silicone rubber.

After the high voltage insulating layer 1330 is formed by vacuum injection, the side surface of the tool connection member 101 is coated with a small amount of silicone rubber, and since the silicone rubber coated on the tool connection member 101 is relatively small, the tool connection member 101 can be directly removed by a tool to expose the tap, and finally the high voltage winding 130 as shown in fig. 8 is formed.

In another embodiment, as shown in fig. 1-4, a dry-type transformer 10 is provided, the dry-type transformer 10 being a three-phase transformer, an a-phase, a B-phase and a C-phase, respectively, the dry-type transformer 10 comprising an iron core 110, three low-voltage windings 120 and three high-voltage windings 130. Wherein, the iron core 110 includes three columnar iron core bodies 111, an upper yoke 112 located at the upper ends of the three columnar iron core bodies 111, and a lower yoke 113 located at the lower ends of the three columnar iron core bodies 111, the three low-voltage windings 120 are respectively sleeved on the outer circumferences of the three columnar iron core bodies 111, and the three high-voltage windings 130 are respectively sleeved on the outer circumferences of the three low-voltage windings 120.

The beneficial effects of the application are as follows: compared with the epoxy resin high-voltage insulating layer in the prior art, the high-voltage winding comprises a winding body, a high-voltage coil and a high-voltage insulating layer of high-temperature vulcanized silicone rubber, and the silicone rubber has the following advantages: 1) The dry-type transformer has better fireproof performance, low-temperature resistance, ageing resistance and short-circuit resistance test capability, and can prolong the service life of the dry-type transformer; 2) The copper coil is easy to peel from the silicon rubber, the material recovery rate is more than 99%, and the copper coil is more environment-friendly; 3) The silicon rubber elastomer can weaken the partial discharge induction caused by mechanical vibration, has an inhibition effect on equipment discharge, and the silicon rubber product is non-conductive silicon dioxide under the discharge effect, so that insulation continuous degradation can be effectively inhibited; 4) The running loss of the transformer can be reduced, and the energy is saved; 5) The ability of resistant adverse circumstances is better, can install indoor and open air. Meanwhile, the silicon rubber is formed by integral high-temperature vulcanization injection molding, compared with the existing room-temperature vulcanization, the process method ensures that the high-voltage insulating layer is firmer and higher in mechanical property, better in bonding property with the high-voltage coil and the winding body, and capable of effectively prolonging the service life of the high-voltage insulating layer. Compared with liquid silicone rubber, the high-temperature vulcanized silicone rubber filler is uniformly dispersed, and partial discharge of the dry-type transformer caused by filler agglomeration is avoided, so that the overall performance of the dry-type transformer is better.

While the present disclosure and features have been described above with respect to specific embodiments, it will be appreciated that those skilled in the art, upon attaining the teachings of the present disclosure, may readily devise numerous variations and modifications of the above-described structures and materials, including combinations of features that are individually disclosed or claimed herein, and obviously other combinations of such features. Such variations and/or combinations fall within the technical field to which the application relates and fall within the scope of the claims of the application.

Claims (9)

1. A preparation method of a high-voltage winding comprises the following steps:

Step ①: the method comprises the steps that a wire is circumferentially wound along the outer peripheral surface of a winding body to form a high-voltage coil, a tap is formed in the wire winding process, the winding body comprises a winding part, the winding part comprises a plurality of winding plates, a plurality of winding grooves are formed in the winding plates, the winding plates form a plurality of comb teeth, and the tooth heights of the comb teeth at two ends of the winding plates and the tooth heights of the comb teeth in the middle of the winding plates are larger than those of the comb teeth in other parts;

step ②: placing the tap in a protection cavity of a tool connecting piece and connecting and fixing the tap with the tool connecting piece;

Step ③: placing the winding body wound with the high-voltage coil as a body to be injected into a mold of an injection machine, and injecting high-temperature vulcanized silicone rubber at the periphery of the body to be injected, so that the high-temperature vulcanized silicone rubber coats the high-voltage coil and the winding body;

Step ④: and removing the tooling connecting piece to obtain the high-voltage winding with the tap exposed out of the high-temperature vulcanized silicone rubber.

2. The method of manufacturing a high-voltage winding according to claim 1, wherein the winding body further includes a support cylinder, the winding portion is located on an outer peripheral surface of the support cylinder, and the wire is wound on the winding portion to form the high-voltage coil in the step ①.

3. The method of manufacturing a high-voltage winding according to claim 2, wherein in the step ①, the wire includes a first wire wound from a first end of the winding portion to a middle portion of the winding portion in an axial direction of the support cylinder and led out of three taps, and a second wire wound from the middle portion of the winding portion to a second end of the winding portion in the axial direction of the support cylinder and led out of three other taps.

4. The method of manufacturing a high voltage winding according to claim 1, wherein in the step ②, the protection cavity is a stepped hole, and the tap is welded in the stepped hole.

5. The method of claim 4, wherein the inner wall of the stepped bore is threaded, and a bolt is coupled to the stepped bore prior to the step ③.

6. The method of manufacturing a high voltage winding according to claim 2, wherein said support cylinder and said winding portion are made of glass fiber impregnated epoxy resin before said step ①.

7. The method of claim 2, wherein a plurality of winding plates are uniformly distributed and adhered on the outer circumferential surface of the supporting cylinder before the step ①.

8. The method of manufacturing a high-voltage winding according to claim 1, wherein in the step ③, the high-temperature vulcanized silicone rubber coats the high-voltage coil and the winding body by integral vacuum injection and fills a gap between the high-voltage coil and the winding body and both ends of the winding body.

9. A high voltage winding, characterized in that it is manufactured by the method for manufacturing a high voltage winding according to any one of claims 1-8.