Axial split coil structure and winding method thereof

Abstract

The invention discloses an axial split coil structure and a winding method thereof.The axial split coil structure comprises an inner side basic barrel, a first coil assembly and a second coil assembly, the lower portion of the innermost side basic barrel is sleeved with the first coil assembly, and the upper portion of the innermost side basic barrel is sleeved with the second coil assembly; a ferrule assembly is arranged between the first coil assembly and the second coil assembly; the split coil at the low-voltage end of the transformer is arranged to be the first coil assembly and the second coil assembly which are of an independent structure, and by the adoption of the structure, the first coil assembly and the second coil assembly can be separated from the innermost base cylinder in the winding process; the height of each coil can be conveniently measured and adjusted after the coil is wound and dried, so that the actual size and the design size of the low-voltage end coil of the transformer are kept consistent, and the product quality is improved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of oil-immersed transformers, in particular to an axial split coil structure and a winding method thereof. BACKGROUND

[0002] In recent years, the global energy transformation and energy infrastructure construction pace has accelerated, bringing about the vigorous development of new energy fields and the new upgrade of traditional power systems. Under this background, global new energy power generation projects are also increasing year by year, such as wind power and solar power generation. New energy power generation single machine capacity is relatively small but the number of units is large. In the process of voltage transformation and transmission, considering the economy, high-voltage large-capacity low-voltage split transformers are often used to reduce transformer cost and land area. For high-voltage split transformers, if the coil adopts an amplitude split structure, it often brings about a complex coil end insulation design, so it is more inclined to adopt an axial split coil structure.

[0003] In addition to the need for reasonable design of high-voltage split transformers, it is also crucial for the quality of the transformer to make the structure reach the design size during the manufacturing process. The coil is an important component of the transformer, and how to ensure that the coil meets the design requirements during winding is also an important consideration in transformer manufacturing. Based on the existing conventional coil structure, it is often impossible to calibrate and adjust the coil after winding, which easily causes the deviation between the actual production size of the coil and the design size.

[0004] In view of the above-mentioned defects, the present inventors have finally obtained the present application after a long period of research and practice. SUMMARY

[0005] To solve the above technical defects, the technical scheme adopted by the present application provides an axial split coil structure, which comprises an innermost base cylinder, a first coil assembly and a second coil assembly. The first coil assembly is sleeved on the lower part of the innermost base cylinder, and the second coil assembly is sleeved on the upper part of the innermost base cylinder. The first coil assembly and the second coil assembly are distributed axially in an up-down manner. A sleeve ring assembly is arranged between the first coil assembly and the second coil assembly. The lower part of the first coil assembly is provided with a bottom oil baffle plate group, a bottom end ring group, a bottom pad group and a bottom sleeve plate group. The bottom sleeve plate group, the bottom pad group, the bottom end ring group and the bottom oil baffle plate group are arranged in sequence from bottom to top on the support end ring. The lower part of the second coil assembly is supported by the sleeve ring assembly. The upper part of the second coil assembly is provided with a top oil baffle plate group, a top end ring group, a top sleeve plate group and a top pad group arranged in sequence from bottom to top.

[0006] The first coil assembly comprises a first inner layer coil, a first insulation cylinder and a first outer layer coil arranged in sequence from inside to outside, a first innermost support strut is arranged between the first inner layer coil and the innermost base cylinder, a first inner side separation strut is arranged between the first inner layer coil and the first insulation cylinder, a first outer side separation strut is arranged between the first insulation cylinder and the first outer layer coil, and a first outermost support strut is arranged outside the first outer layer coil to support and stabilize the overall structure of the first coil assembly.

[0007] The second coil assembly comprises a second inner layer coil, a second insulation cylinder and a second outer layer coil arranged in sequence from inside to outside, a second innermost support strut is arranged between the second inner layer coil and the innermost base cylinder, a second inner side separation strut is arranged between the second inner layer coil and the second insulation cylinder, a second outer side separation strut is arranged between the second insulation cylinder and the second outer layer coil, and a second outermost support strut is arranged outside the second outer layer coil to support and stabilize the overall structure of the second coil assembly, and a support pad plate is arranged at the bottom of the second outer layer coil.

[0008] A first inner side sleeve plate, a first inner side electrostatic ring and a first inner side angle ring are arranged on the inner diameter side above the first inner layer coil, the first inner side electrostatic ring is arranged between the first inner side angle ring and the first inner layer coil, and the first inner side sleeve plate is arranged between the first inner side electrostatic ring and the first inner side angle ring and between the first inner side electrostatic ring and the first inner layer coil, a first outer side sleeve plate, a first outer side electrostatic ring and a first outer side angle ring are arranged on the outer diameter side above the first outer layer coil, the first outer side electrostatic ring is arranged between the first outer side angle ring and the first outer layer coil, and the first outer side sleeve plate is arranged between the first outer side electrostatic ring and the first outer side angle ring and between the first outer side electrostatic ring and the first outer layer coil.

[0009] A second inner side sleeve plate, a second inner side electrostatic ring and a second inner side angle ring are arranged on the inner diameter side below the second inner layer coil, the second inner side electrostatic ring is arranged between the second inner side angle ring and the second inner layer coil, and the second inner side sleeve plate is arranged between the second inner side electrostatic ring and the second inner side angle ring and between the second inner side electrostatic ring and the second inner layer coil, a second outer side sleeve plate, a second outer side electrostatic ring and a second outer side angle ring are arranged on the outer diameter side below the second outer layer coil, the second outer side electrostatic ring is arranged between the second outer side angle ring and the second outer layer coil, and the second outer side sleeve plate is arranged between the second outer side electrostatic ring and the second outer side angle ring and between the second outer side electrostatic ring and the second outer layer coil.

[0010] Preferably, a winding method for manufacturing the axial split coil structure comprises the following steps:

[0011] S1, the first coil assembly and the second coil assembly are wound on the innermost base cylinder to form the prefabricated split coil;

[0012] S2, the prefabricated split coil is pressure dried;

[0013] S3, the first coil assembly and the second coil assembly are separated from the innermost base cylinder and are sized and adjusted to form the axial split coil structure.

[0014] Preferably, in the step S1, the support end ring is placed on the support platform at the lower part of the vertical winding machine, then the innermost base cylinder is sleeved into the vertical winding machine and placed on the support end ring; the first innermost support strut is placed on the outer surface of the innermost base cylinder in a ring shape at equal intervals, and the first innermost support strut is lifted to have a height gap with the support end ring; the bottom sleeve plate group, the bottom cushion block group, the bottom end ring group and the bottom oil baffle group are placed on the support end ring in sequence.

[0015] Preferably, the first inner layer coil is wound from the bottom of the first coil assembly upwards, and after winding to the top of the first inner layer coil, the first inner side electrostatic ring outgoing wire is welded with a single elementary wire of the lead; after welding, the first inner side separation strut, the first insulating cylinder and the first outer side separation strut are placed, then the lead is transitioned outside to the outer diameter side of the first coil assembly to start winding the first outer layer coil, and the lead of the first outer layer coil is supported by a winding tool, and the outside of the winding tool is tightened by a tightening belt; after the first pie line at the upper part of the first outer layer coil is wound, the first outer side electrostatic ring outgoing wire is welded with a single elementary wire of the lead, and after the first outer layer coil is wound, the first outer layer coil is located on the previously placed bottom end ring group and bottom oil baffle group.

[0016] Preferably, after the first coil assembly is wound, the sleeve ring assembly is arranged on the first inner side electrostatic ring and the first outer side electrostatic ring, the second innermost support strut is arranged on the sleeve ring assembly, then the second inner layer coil is wound from the upper part to the lower part, and the lead of the second inner layer coil is supported by a winding tool, and the outside of the winding tool is tightened by the tightening belt.

[0017] Preferably, after winding to the bottom of the second inner layer coil, the outgoing wire of the second inner static ring is welded with the single wire of the wire; after welding, the second inner side partition support, the second insulating cylinder and the second outer side partition support are placed, and then the second outer static ring is placed, and then the wire of the second inner layer coil is transitioned to the outer diameter side of the second coil assembly to start winding the second outer layer coil. When the first pie wire at the lower part of the second outer layer coil is wound, the outgoing wire of the second outer static ring is welded with the single wire of the wire; after welding, the second outer layer coil is continuously wound from the lower part to the upper part, and the second outer layer coil is wound to form the prefabricated split coil on the previously placed sleeve ring assembly.

[0018] Preferably, in the step S3, the second coil assembly is pulled out of the prefabricated split coil, and then the second coil assembly is pressed by using a pressing device to measure the height of the second inner layer coil and the second outer layer coil; according to the height measurement result, the inner oil channel size of the second inner layer coil and the second outer layer coil is adjusted to make the height of the second inner layer coil and the second outer layer coil within the design requirement range, and finally the second outermost support support is installed to make the second outermost support support arranged on the support base plate, and the outer side of the second outermost support support is tightened.

[0019] Preferably, after pulling out the innermost base cylinder, the sleeve ring assembly is removed, the first innermost support support is adjusted to make the first innermost support support contact the support end ring; the first coil assembly is pressed by using the pressing device to measure the height of the first inner layer coil and the first outer layer coil; according to the height measurement result, the inner oil channel size of the first inner layer coil and the first outer layer coil is adjusted to make the height of the first inner layer coil and the first outer layer coil within the design requirement range, and finally the first outermost support support is installed to make the first outermost support support arranged on the support base plate, and the outer side of the first outermost support support is tightened.

[0020] Preferably, after the height adjustment of the first coil assembly is completed, the innermost base cylinder is re-embedded into the first coil assembly, and then the first inner corner ring and the first outer corner ring are installed; secondly, the sleeve ring assembly is placed on the first inner corner ring and the first outer corner ring of the first coil assembly; then, when the second coil assembly is sleeved on the innermost base cylinder and has an installation gap with the first coil assembly, the second inner corner ring and the second outer corner ring are installed; after the second inner corner ring and the second outer corner ring are placed, the second coil assembly is continuously sleeved downward until it falls on the sleeve ring assembly; finally, the top oil baffle group, the top end ring group, the top sleeve plate group and the top pad group on the upper part of the second coil assembly are placed, so that the winding of the axial split coil structure is completed.

[0021] Preferably, the winding tool comprises a connecting plate and a supporting plate, the supporting plate is fixed vertically at one end of the connecting plate to form an L-shaped structure, a clamping groove is arranged on the side of the connecting plate away from the supporting plate, the extension direction of the clamping groove is consistent with the extension direction of the connecting plate, the first outer side separation support or the second innermost support is arranged in the clamping groove, and the upper end surface of the supporting plate is arranged horizontally to support the first outer layer coil or the second inner layer coil above.

[0022] Compared with the prior art, the beneficial effects of the present application are as follows: 1. The split coil at the low-voltage end of the transformer is arranged as the first coil assembly and the second coil assembly in two independent structures, so that the first coil assembly and the second coil assembly can be separated from the innermost base cylinder during winding, which facilitates the measurement and adjustment of the height of each coil after drying, thereby ensuring that the actual size of the transformer low-voltage end coil is consistent with the design size, so as to improve product quality; 2. The present application provides a novel winding method of the axial split coil structure with an insulation structure, which can measure and adjust the height of each coil after drying to ensure that the actual production size of the transformer low-voltage end coil is consistent with the design size, and the insulation structure is safe and reliable during coil assembly. BRIEF DESCRIPTION OF DRAWINGS

[0023] Figure 1 It is a structural view of the axial split coil structure;

[0024] Figure 2 It is a structural view of the first coil assembly after winding in step S1;

[0025] Figure 3 It is a structural view of the sleeve ring assembly placed in step S1;

[0026] Figure 4 Structure diagram of the second coil assembly after being wound in the step S1;

[0027] Figure 5 Structure diagram of the second coil assembly after being separated in the step S3;

[0028] Figure 6 Structure diagram of the first coil assembly after being separated in the step S3;

[0029] Figure 7 Structure diagram of the step S3 of installing the angle ring;

[0030] Figure 8 Structure front view of the winding tool;

[0031] Figure 9 Structure top view of the winding tool;

[0032] Figure 10 Structure front view of the first outer layer coil winding using the winding tool;

[0033] Figure 11 Structure bottom view of the first outer layer coil winding using the winding tool;

[0034] Figure 12 Structure front view of the second inner layer coil winding using the winding tool;

[0035] Figure 13 Structure bottom view of the second inner layer coil winding using the winding tool.

[0036] Figures in the drawings represent:

[0037] 1-Innermost base cylinder; 2-First coil assembly; 3-Second coil assembly; 4-Ring assembly; 5-Support end ring; 8-Winding fixture; 9-Tightening belt; 21-First inner layer coil; 22-First insulating cylinder; 23-First outer layer coil; 24-First innermost support bar; 25-First innermost partition bar; 26-First outermost partition bar; 27-First outermost support bar; 31-Second inner layer coil; 32-Second insulating cylinder; 33-Second outer layer coil; 34-Second innermost support bar; 35-Second innermost partition bar; 36-Second outermost partition bar; 37-Second outermost support bar; 38-Support pad; 41-First lower pad; 42-Second lower pad; 43-Upper pad; 44-Intermediate partition plate assembly; 61-Bottom oil baffle plate assembly; 6 2- Bottom end ring assembly; 63- Bottom pad assembly; 64- Bottom sleeve plate assembly; 71- Top oil baffle plate assembly; 72- Top end ring assembly; 73- Top sleeve plate assembly; 74- Top pad plate assembly; 81- Connecting plate; 82- Support plate; 83- Snap-fit ​​groove; 211- First inner sleeve plate; 212- First inner static ring; 213- First inner corner ring; 231- First outer sleeve plate; 232- First outer static ring; 233- First outer corner ring; 311- Second inner sleeve plate; 312- Second inner static ring; 313- Second inner corner ring; 331- Second outer sleeve plate; 332- Second outer static ring; 333- Second outer corner ring; 611- Bottom inner oil baffle plate; 612- Bottom outer oil baffle plate; 621- Bottom inner end ring; 622- Bottom outer end ring. Detailed Implementation

[0038] The above-mentioned and other technical features and advantages of the present invention will be described in more detail below with reference to the accompanying drawings.

[0039] Example 1

[0040] like Figure 1 As shown, Figure 1 This is a structural view of the axially split coil structure.

[0041] The axial split coil structure comprises an innermost base cylinder 1, a first coil assembly 2 and a second coil assembly 3, the first coil assembly 2 is sleeved on the lower part of the innermost base cylinder 1, the second coil assembly 3 is sleeved on the upper part of the innermost base cylinder 1, the first coil assembly 2 and the second coil assembly 3 are axially distributed in an up-down manner, a sleeve assembly 4 is arranged between the first coil assembly 2 and the second coil assembly 3, the lower part of the first coil assembly 2 is provided with a bottom oil baffle plate group 61, a bottom end ring group 62, a bottom pad group 63 and a bottom sleeve plate group 64, the bottom sleeve plate group 64, the bottom pad group 63, the bottom end ring group 62 and the bottom oil baffle plate group 61 are sequentially arranged from bottom to top on a support end ring 5, the first coil assembly 2 is supported and fixed in the whole structure and position by the support end ring 5, the lower part of the second coil assembly 3 is supported by the sleeve assembly 4, and the upper part of the second coil assembly 3 is sequentially provided with a top oil baffle plate group 71, a top end ring group 72, a top sleeve plate group 73 and a top pad group 74 from bottom to top.

[0042] Specifically, the first coil assembly 2 comprises a first inner layer coil 21, a first insulation cylinder 22 and a first outer layer coil 23 which are sequentially arranged from inside to outside, a first innermost support strut 24 is arranged between the first inner layer coil 21 and the innermost base cylinder 1, a first inner side separation strut 25 is arranged between the first inner layer coil 21 and the first insulation cylinder 22, a first outer side separation strut 26 is arranged between the first insulation cylinder 22 and the first outer layer coil 23, and a first outermost support strut 27 is arranged outside the first outer layer coil 23 to support and stabilize the whole structure of the first coil assembly 2.

[0043] A first inner side sleeve plate 211, a first inner side electrostatic ring 212 and a first inner side angle ring 213 are arranged on the inner diameter side above the first inner layer coil 21, the first inner side electrostatic ring 212 is arranged between the first inner side angle ring 213 and the first inner layer coil 21, and the first inner side sleeve plate 211 is arranged between the first inner side electrostatic ring 212 and the first inner side angle ring 213 and between the first inner side electrostatic ring 212 and the first inner layer coil 21, a first outer side sleeve plate 231, a first outer side electrostatic ring 232 and a first outer side angle ring 233 are arranged on the outer diameter side above the first outer layer coil 23, the first outer side electrostatic ring 232 is arranged between the first outer side angle ring 233 and the first outer layer coil 23, and the first outer side sleeve plate 231 is arranged between the first outer side electrostatic ring 232 and the first outer side angle ring 233 and between the first outer side electrostatic ring 232 and the first outer layer coil 23.

[0044] The second coil assembly 3 comprises a second inner layer coil 31, a second insulation cylinder 32 and a second outer layer coil 33 arranged in sequence from inside to outside, a second innermost support strut 34 is arranged between the second inner layer coil 31 and the innermost base cylinder 1, a second inner side separation strut 35 is arranged between the second inner layer coil 31 and the second insulation cylinder 32, a second outer side separation strut 36 is arranged between the second insulation cylinder 32 and the second outer layer coil 33, and a second outermost support strut 37 is arranged outside the second outer layer coil 33 to support and stabilize the overall structure of the second coil assembly 3, and a support pad 38 is arranged at the bottom of the second outer layer coil 33 to support the second outermost support strut 37.

[0045] A second inner side sleeve plate 311, a second inner side electrostatic ring 312 and a second inner side angle ring 313 are arranged on the inner diameter side below the second inner layer coil 31, the second inner side electrostatic ring 312 is arranged between the second inner side angle ring 313 and the second inner layer coil 31, and the second inner side sleeve plate 311 is arranged between the second inner side electrostatic ring 312 and the second inner side angle ring 313 and between the second inner side electrostatic ring 312 and the second inner layer coil 31, and a second outer side sleeve plate 331, a second outer side electrostatic ring 332 and a second outer side angle ring 333 are arranged on the outer diameter side below the second outer layer coil 33, the second outer side electrostatic ring 332 is arranged between the second outer side angle ring 333 and the second outer layer coil 33, and the second outer side sleeve plate 331 is arranged between the second outer side electrostatic ring 332 and the second outer side angle ring 333 and between the second outer side electrostatic ring 332 and the second outer layer coil 33.

[0046] The insulation structure adopted in the application effectively ensures the insulation of the inner diameter side core by the upper end of the first coil assembly 2 and the lower end of the second coil assembly 3, the insulation between the upper end of the first coil assembly 2 and the lower end of the second coil assembly 3, and the insulation between the first coil assembly 2 and the second coil assembly 3 and the outer side high-voltage coil.

[0047] The sleeve assembly 4 comprises a middle separation pad group and a middle separation sleeve plate group 44, and the middle separation pad group is arranged between the middle separation sleeve plate group 44 and the first coil assembly 2 and the second coil assembly 3 to stably support the second coil assembly 3.

[0048] Preferably, the middle partition pad group comprises a first lower pad 41, a second lower pad 42 and an upper pad 43, the first lower pad 41 and the second lower pad 42 are arranged at the bottom of the middle partition sleeve plate group 44, the first lower pad 41 and the second lower pad 42 correspond to the first inner layer coil 21 and the first outer layer coil 23 respectively, and the upper pad 43 is arranged at the top of the middle partition sleeve plate group 44 to support the second inner layer coil 31, the second insulation cylinder 32 and the second outer layer coil 33.

[0049] In the case of connecting power supply to both low-voltage sides of the split, the short circuit between the two split low-voltage sides needs to be considered. In order to improve the short circuit resistance of the large-capacity axial split transformer when a short circuit occurs between the two split low-voltage sides, the transformer is usually required to have a high impedance split coefficient to increase the impedance between the two split low-voltage coils. Increasing the axial distance between the two axial split coil structures can increase the impedance therebetween, but also brings insulation problems. The present application provides a reliable insulation structure by arranging electrostatic rings and angle rings on the inner and outer diameter sides between the two axial split coil structures, thereby ensuring the insulation of the two axial split coil structures to the inner side of the core, the insulation between the two axial split coil structures, and the insulation of the two axial split coil structures to the outer side of the high-voltage coil.

[0050] Specifically, the first inner layer coil 21 and the first outer layer coil 23 are both spiral structures and are connected at the top of the first coil assembly 2 through transition transposition to form a ∩-shaped coil structure; the second inner layer coil 31 and the second outer layer coil 33 are both spiral structures and are connected at the bottom of the second coil assembly 3 through transition transposition to form a U-shaped coil structure; the first coil assembly 2 and the second coil assembly 3 are both provided with strong oil guiding and cooling structures.

[0051] Preferably, the bottom oil baffle group 61 comprises a bottom inner side oil baffle 611 and a bottom outer side oil baffle 612, the bottom inner side oil baffle 611 is arranged below the first inner layer coil 21, the bottom outer side oil baffle 612 is arranged below the first outer layer coil 23, and the bottom inner side oil baffle 611 and the bottom outer side oil baffle 612 are separated by the first insulation cylinder 22 to ensure the stability of the strong oil guiding and cooling structures of the first inner layer coil 21 and the first outer layer coil 23; the bottom end ring group 62 comprises a bottom inner side end ring 621 and a bottom outer side end ring 622, the bottom inner side end ring 621 and the bottom inner side oil baffle 611 are arranged correspondingly, and the bottom outer side end ring 622 and the bottom outer side oil baffle 612 are arranged correspondingly to ensure the stability of the positions of the bottom inner side oil baffle 611 and the bottom outer side oil baffle 612.

[0052] The top oil baffle assembly 71 includes a top inner oil baffle and a top outer oil baffle; the top end ring assembly 72 includes a top inner end ring and a top outer end ring; the top sleeve assembly 73 includes a top inner sleeve and a top outer sleeve; and the top pad assembly 74 includes a top inner pad and a top outer pad. The top inner oil baffle, the top inner end ring, the top inner sleeve, and the top inner pad are respectively disposed above the second inner layer coil 31, and the top outer oil baffle, the top outer end ring, the top outer sleeve, and the top outer pad are respectively disposed above the second outer layer coil 33, ensuring the stability of the strong oil-guided cooling structure of the second inner layer coil 31 and the second outer layer coil 33.

[0053] Because the coil losses of large-capacity axially split transformers are relatively high, the structure of this invention adopts a strong oil-guided cooling structure, which, compared with conventional self-cooling methods, can more effectively reduce coil temperature rise, extend transformer service life, and reduce the number of cooling devices required.

[0054] The present invention sets the split coil of the low-voltage end of the transformer as two independent structures: the first coil assembly 2 and the second coil assembly 3. With this structure, the first coil assembly 2 and the second coil assembly 3 can be separated from the innermost base cylinder 1 during the winding process. This facilitates the measurement and adjustment of the height of each coil after winding and drying, thereby ensuring that the actual size of the transformer low-voltage end coil is consistent with the design size, thus improving product quality.

[0055] Example 2

[0056] The winding method of the present invention is used to fabricate the axially split coil structure, and includes the following steps:

[0057] S1, the first coil assembly 2 and the second coil assembly 3 are wound on the innermost base cylinder 1 to form a prefabricated split coil;

[0058] S2, the prefabricated split coil is dried under pressure;

[0059] S3, the first coil assembly 2 and the second coil assembly 3 are detached from the innermost base cylinder 1, their dimensions are adjusted, and then they are reinstalled.

[0060] like Figures 2 to 7 As shown, Figure 2 This is a schematic diagram of the structure of the first coil assembly after winding in step S1; Figure 3 This is a schematic diagram of the structure in which the ring assembly is placed in step S1; Figure 4 This is a schematic diagram of the structure of the second coil assembly after winding in step S1; Figure 5The structure schematic diagram after the second coil assembly is separated in step S3; Figure 6 The structure schematic diagram after the first coil assembly is separated in step S3; Figure 7 The structure schematic diagram of installing the angle ring in step S3.

[0061] Specifically, in step S1, the support end ring 5 is placed on the support platform at the lower part of the vertical winding machine, and then the innermost base cylinder 1 is sleeved into the vertical winding machine and placed on the support end ring 5; secondly, the first innermost support strut 24 is placed on the outer surface of the innermost base cylinder 1 in a ring shape at equal intervals, and the first innermost support strut 24 is lifted to not contact the support end ring 5; then the bottom sleeve plate group 64, the bottom cushion block group 63, the bottom end ring group 62 and the bottom oil baffle group 61 are placed in sequence on the support end ring 5.

[0062] Then, the first inner layer coil 21 is wound from the bottom of the first coil assembly 2 upwards, and after winding to the top of the first inner layer coil 21, the first inner static ring 212 outgoing wire is welded with a single element wire; after welding, the first inner separation strut 25, the first insulating cylinder 22 and the first outer separation strut 26 are placed, and then the wire is transitioned to the outer diameter side of the first coil assembly 2 to wind the first outer layer coil 23, and the winding tool 8 is used to support the wire of the first outer layer coil 23; after the first pie wire at the upper part of the first outer layer coil 23 is wound, the first outer static ring 232 outgoing wire is welded with a single element wire.

[0063] Since the first outer layer coil 23 is wound from the upper part to the lower part, the winding tool 8 is used to support the wire along the winding direction during winding, and the tightening belt 9 is used to tighten the outer side of the winding tool 8. After the first outer layer coil 23 is wound, it is located on the previously placed bottom end ring group 62 and bottom oil baffle group 61.

[0064] After the first coil assembly 2 is wound, the sleeve plate is placed on the first inner static ring 212 and the first outer static ring 232, the sleeve ring assembly 4 is arranged on the sleeve plate, the second innermost support strut 34 is arranged on the sleeve ring assembly 4, and then the second inner layer coil 31 is wound from the upper part to the lower part. The winding process of the second inner layer coil 31 uses the winding tool 8 to support the wire along the winding direction, and the tightening belt 9 is used to tighten the outer side of the winding tool 8.

[0065] After winding to the bottom of the second inner layer coil 31, the outgoing line of the second inner side electrostatic ring 312 is welded with the single element wire of the lead wire; after welding, the second inner side partitioning strut 35, the second insulating cylinder 32 and the second outer side partitioning strut 36 are placed, then the second outer side electrostatic ring 332 is placed, and then the lead wire of the second inner layer coil 31 is transitioned to the outer diameter side of the second coil assembly 3 to start winding the second outer layer coil 33. After the first pie line at the lower part of the second outer layer coil 33 is wound, the outgoing line of the second outer side electrostatic ring 332 is welded with the single element wire of the lead wire; after welding, the second outer layer coil 33 is continuously wound from the lower part to the upper part, and the second outer layer coil 33 is wound on the previously placed sleeve ring assembly 4 after being wound.

[0066] In the step S2, after the pre-split coil wound in the step S1 is lifted from the vertical wire winder, the upper part of the second coil assembly 3 is pressed and compressed by using the existing conventional compression device, the first coil assembly 2 is subjected to the compression force transmitted from the upper part to the lower part by the second coil assembly 3, and then the pre-split coil and the compression device are placed in a vacuum drying tank; in addition, the insulating parts such as the corner ring, the strut and the end ring which need to be assembled subsequently are also placed in the vacuum drying tank. Then the vacuum drying system is started to dry the pre-split coil and the subsequent installation parts. After drying is completed, the pre-split coil and the subsequent installation parts are removed from the vacuum drying tank.

[0067] In the step S3, the second coil assembly 3 is pulled out of the pre-split coil, and then the second coil assembly 3 is pressurized by using the compression device, and the height of the second inner layer coil 31 and the second outer layer coil 33 is measured; according to the height measurement result, the inner oil channel size of the second inner layer coil 31 and the second outer layer coil 33 is adjusted so that the height is within the design requirement range, and finally the second outermost layer support strut 37 is installed so as to fall on the support pad plate 38 extended at the lower part of the second outer layer coil 33, and the polyester tape is used to bind and tighten outside the second outermost layer support strut 37.

[0068] After the innermost side base cylinder 1 is pulled out, the sleeve ring assembly 4 is removed, the first innermost side support strut 24 is slightly knocked down to fall on the support end ring 5; the first coil assembly 2 is pressurized by using the compression device, and the height of the first inner layer coil 21 and the first outer layer coil 23 is measured; according to the height measurement result, the inner oil channel size of the first inner layer coil 21 and the first outer layer coil 23 is adjusted so that the height is within the design requirement range, and finally the first outermost layer support strut 27 is installed, and the polyester tape is used to bind and tighten outside the first outermost layer support strut 27.

[0069] After the first coil assembly 2 height adjustment is completed, the innermost base cylinder 1 is re-embedded into the first coil assembly 2, and then the first inner corner ring 213 and the first outer corner ring 233 of the first coil assembly 2 are installed; secondly, the sleeve ring assembly 4 is placed on the first inner corner ring 213 and the first outer corner ring 233 of the first coil assembly 2; then the second coil assembly 3 is sleeved into the innermost base cylinder 1 for a distance, and the second inner corner ring 313 and the second outer corner ring 333 of the second coil assembly 3 are installed; after the second inner corner ring 313 and the second outer corner ring 333 are placed, the second coil assembly 3 is continuously sleeved downward until it falls on the sleeve ring assembly 4; finally, the top oil baffle group 71, the top end ring group 72, the top sleeve plate group 73, and the top pad group 74 on the upper part of the second coil assembly 3 are placed, thereby completing the winding of the axial split coil structure.

[0070] In order to avoid the innermost base cylinder 1 and other insulation components being exposed for too long after the coil is baked, which can cause moisture absorption and lead to dimensional changes in the insulation components, the step S3 must be completed within 24 hours after the pre-baking of the split coil.

[0071] The axial split coil structure is wound on a vertical winding machine. Compared with winding on a horizontal winding machine, winding on a vertical winding machine is more conducive to the axial positioning of the axial split coil structure and facilitates the welding of the electrostatic ring and the wire.

[0072] After the first inner layer coil 21 is wound, the height of the first inner layer coil 21 will be higher than the design height due to the lack of drying and compression. If the first innermost support strut 24 is not long enough, the upper end surface of the wound first inner layer coil 21 may exceed the upper end of the first innermost support strut 24. However, if the overall length of the first innermost support strut 24 is set too long, it will easily interfere with the first inner corner ring 213. Therefore, before winding the first inner layer coil 21, the first innermost support strut 24 is lifted upward by a certain distance so that the winding range of the first inner layer coil 21 is on the first innermost support strut 24, preventing the upper end surface of the first inner layer coil 21 from exceeding the upper end of the first innermost support strut 24. This avoids the situation where the first inner corner electrostatic ring 212 is stuck by the first innermost support strut 24 during the downward movement caused by being pressed and deviated by the first inner layer coil 21 during drying and compression. The lifted first innermost support strut 24 can be fixed by tightening the thin tensioning belt first, and then the thin tensioning belt is cut after completing part of the coil cake. After the first inner layer coil 21 is dried and compressed, the first innermost support strut 24 will be slightly knocked down to fall on the support end ring 5.

[0073] The outgoing line of each electrostatic ring is directly welded with a single element of the corresponding wire; the outgoing line of the electrostatic ring does not need to be led out.

[0074] The winding tool 8 is used in the process of winding the first outer layer coil 23 from top to bottom and the process of winding the second inner layer coil 31 from top to bottom, the winding tool 8 is fixed on the corresponding strut, the outer periphery of each tool is tightened with the tightening belt 9, and the upper wire cake is supported.

[0075] As shown in Figures 8 to 13 , the structure of the winding tool is shown in the front view; Figure 8 , the structure of the winding tool is shown in the front view; Figure 9 , the structure of the winding tool is shown in the front view; Figure 10 , the structure of the winding tool is shown in the front view; Figure 11 , the structure of the winding tool is shown in the front view; Figure 12 , the structure of the winding tool is shown in the front view; Figure 13 , the structure of the winding tool is shown in the front view.

[0076] Specifically, the winding tool 8 includes a connecting plate 81 and a supporting plate 82, the supporting plate 82 is fixed vertically at one end of the connecting plate 81 to form an L-shaped structure, the side of the connecting plate 81 away from the supporting plate 82 is provided with a clamping groove 83, the extension direction of the clamping groove 83 is consistent with the extension direction of the connecting plate 81, and the corresponding first outer side separation strut 26 or the second innermost side supporting strut 34 is arranged in the clamping groove 83 to realize the fixation of the winding tool 8 at the corresponding position. The upper end surface of the supporting plate 82 is horizontally arranged to support the upper wire cake, and the tightening belt 9 is sleeved on the connecting plate 81 of the plurality of winding tools 8 arranged in a ring shape to realize the position fixation of the plurality of winding tools 8.

[0077] After the drying is completed, the height of the second inner layer coil 31 and the second outer layer coil 33 is measured and adjusted by pulling out the innermost base cylinder 1 from the innermost side, so that the height of the coil is ensured to be within the design requirement range.

[0078] After the drying is completed, the height of the first inner layer coil 21 and the first outer layer coil 23 is measured and adjusted by pulling out the innermost base cylinder 1 from the innermost side, so that the height of the coil is ensured to be within the design requirement range.

[0079] The first inner side corner ring 213 and the first outer side corner ring 233 of the first coil assembly 2 are not installed in the step S1, but are installed after the height adjustment of the first inner layer coil 21 and the first outer layer coil 23, so as to avoid the first inner side corner ring 213 from being damaged by the first innermost support strut 24 during the drying process and the pulling-out process of the innermost base cylinder 1.

[0080] The second inner side corner ring 313 and the second outer side corner ring 333 of the second coil assembly 3 are not installed in the step S1, but are installed after the height adjustment of the second inner layer coil 31 and the second outer layer coil 33, so as to avoid the second inner side corner ring 313 from being damaged by the second innermost support strut 34 during the drying process and the pulling-out process of the innermost base cylinder 1.

[0081] In order to avoid the innermost base cylinder 1 and other insulation components from being exposed for too long time after the drying of the coil, which may cause the components to be dampened, the size of the components to be changed, the innermost base cylinder 1 to be difficultly re-embedded, and the measurement results of the coil height to be affected, the step S3 must be completed within 24 hours after the drying of the coil.

[0082] The application provides a winding method of a novel insulation structure axial split coil structure, which can measure and adjust the height of each coil after drying, so as to ensure that the actual production size of the low-voltage end coil of the transformer is consistent with the design size, and the insulation structure is safe and reliable during the coil assembly process.

[0083] The above description is only the preferred embodiment of the application, which is only illustrative but not limiting. It is understood by those skilled in the art that many changes, modifications and even equivalents can be made to the application within the spirit and scope of the claims of the application, but all will fall within the protection scope of the application.

Claims

1. An axially split coil structure, characterized in that, The system includes an innermost base cylinder, a first coil assembly, and a second coil assembly. The first coil assembly is sleeved on the lower part of the innermost base cylinder, and the second coil assembly is sleeved on the upper part of the innermost base cylinder. The first coil assembly and the second coil assembly are distributed vertically along the axis. A collar assembly is provided between the first coil assembly and the second coil assembly. The lower part of the first coil assembly is provided with a bottom oil baffle plate assembly, a bottom end ring assembly, a bottom pad assembly, and a bottom sleeve plate assembly. The bottom sleeve plate assembly, the bottom pad assembly, the bottom end ring assembly, and the bottom oil baffle plate assembly are arranged sequentially from bottom to top on the supporting end ring. The lower part of the second coil assembly is supported by the collar assembly. The upper part of the second coil assembly is provided with a top oil baffle plate assembly, a top end ring assembly, a top sleeve plate assembly, and a top pad assembly sequentially from bottom to top. The first coil assembly includes a first inner coil, a first insulating cylinder, and a first outer coil arranged sequentially from the inside to the outside. A first innermost support bar is provided between the first inner coil and the innermost base cylinder. A first inner dividing bar is provided between the first inner coil and the first insulating cylinder. A first outer dividing bar is provided between the first insulating cylinder and the first outer coil. A first outermost support bar is provided outside the first outer coil. The second coil assembly includes a second inner coil, a second insulating cylinder, and a second outer coil arranged sequentially from the inside out. A second innermost support bar is provided between the second inner coil and the innermost base cylinder. A second inner dividing support bar is provided between the second inner coil and the second insulating cylinder. A second outer dividing support bar is provided between the second insulating cylinder and the second outer coil. A second outermost support bar is provided on the outside of the second outer coil. A support pad is provided at the bottom of the second outer coil. A first inner electrostatic ring and a first inner corner ring are provided on the inner diameter side above the first inner coil. The first inner electrostatic ring is disposed between the first inner corner ring and the first inner coil. A first outer electrostatic ring and a first outer corner ring are provided on the outer diameter side above the first outer coil. The first outer electrostatic ring is disposed between the first outer corner ring and the first outer coil. A second inner electrostatic ring and a second inner corner ring are provided on the inner diameter side below the second inner coil. The second inner electrostatic ring is located between the second inner corner ring and the second inner coil. A second outer electrostatic ring and a second outer corner ring are provided on the outer diameter side below the second outer coil. The second outer electrostatic ring is located between the second outer corner ring and the second outer coil.

2. A winding method, characterized in that, To fabricate the axially split coil structure as described in claim 1, the steps include: S1, the first coil assembly and the second coil assembly are wound on the innermost base cylinder to form a prefabricated split coil; S2, the prefabricated split coil is dried under pressure; S3, the first coil assembly and the second coil assembly are detached from the innermost base cylinder, their dimensions are adjusted, and then they are reinstalled to form the axial split coil structure.

3. The winding method as described in claim 2, characterized in that, In step S1, the support end ring is placed on the support platform at the bottom of the vertical winding machine. Then, the innermost base cylinder is inserted into the vertical winding machine and placed on the support end ring. The first innermost support strip is placed circumferentially at equal intervals on the outer surface of the innermost base cylinder, and the first innermost support strip is raised to set a height gap with the support end ring. The bottom sleeve plate group, the bottom pad block group, the bottom end ring group, and the bottom oil baffle plate group are placed on the support end ring in sequence.

4. The winding method as described in claim 3, characterized in that, Starting from the bottom of the first coil assembly, the first inner coil is wound upwards. After winding to the top of the first inner coil, the lead of the first inner electrostatic ring is welded to a single strand of wire. After welding, the first inner separator support, the first insulating cylinder, and the first outer separator support are placed. Then, the outer side of the wire is transitioned to the outer diameter side of the first coil assembly to begin winding the first outer coil. The wire of the first outer coil is supported by a winding fixture, and the outer side of the winding fixture is tightened with a tightening tape. After the first disc wire at the top of the first outer coil is wound, the lead of the first outer electrostatic ring is welded to a single strand of wire. After the first outer coil is wound, it is located on the previously placed bottom end coil assembly and bottom oil baffle assembly.

5. The winding method as described in claim 4, characterized in that, After the first coil assembly is wound, the collar assembly is set on the first inner electrostatic ring and the first outer electrostatic ring, and the second innermost support bar is set on the collar assembly. Then, the second inner layer coil is wound from top to bottom, and the wire of the second inner layer coil is supported by the winding fixture. The outer side of the winding fixture is tightened by the tightening tape.

6. The winding method as described in claim 5, characterized in that, After winding to the bottom of the second inner layer coil, the lead of the second inner electrostatic ring is welded to a single strand of wire. After welding, the second inner separator bar, the second insulating cylinder, and the second outer separator bar are placed, and then the second outer electrostatic ring is placed. Subsequently, the outer strand of the second inner layer coil is transitioned to the outer diameter side of the second coil assembly to begin winding the second outer layer coil. When the first disc of the second outer layer coil is wound, the lead of the second outer electrostatic ring is welded to a single strand of wire. After welding, the second outer layer coil continues to be wound from bottom to top. After the second outer layer coil is wound, it is placed on the previously placed coil assembly to form the prefabricated split coil.

7. The winding method as described in claim 2, characterized in that, In step S3, the second coil assembly is pulled out from the prefabricated split coil, and then a clamping device is used to pressurize the second coil assembly. The heights of the second inner coil and the second outer coil are measured. Based on the height measurement results, the inner oil passage dimensions of the second inner coil and the second outer coil are adjusted so that the heights of the second inner coil and the second outer coil are within the design requirements. Finally, the second outermost support bar is installed so that the second outermost support bar is placed on the support pad, and the outer side of the second outermost support bar is tied and tightened.

8. The winding method as described in claim 7, characterized in that, After pulling out the innermost base cylinder, remove the collar assembly and adjust the first innermost support bar so that it contacts the support end ring. Pressurize the first coil assembly using the clamping device and measure the height of the first inner coil and the first outer coil. Based on the height measurement results, adjust the oil passage dimensions of the first inner coil and the first outer coil so that their heights are within the design requirements. Finally, install the first outermost support bar so that it is positioned on the support pad and tighten the outer side of the first outermost support bar.

9. The winding method as described in claim 8, characterized in that, After the height of the first coil assembly is adjusted, the innermost base cylinder is re-embedded into the first coil assembly, and then the first inner corner ring and the first outer corner ring are installed. Next, the collar assembly is placed on the first inner corner ring and the first outer corner ring of the first coil assembly. Then, when the second coil assembly is fitted onto the innermost base cylinder and there is an installation gap between it and the first coil assembly, the second inner corner ring and the second outer corner ring are installed. After the second inner corner ring and the second outer corner ring are placed, the second coil assembly is continued to be fitted downwards until it falls onto the collar assembly. Finally, the top oil baffle assembly, the top end ring assembly, the top sleeve assembly, and the top pad assembly on the upper part of the second coil assembly are placed, thereby completing the winding of the axial split coil structure.

10. The winding method as described in claim 5, characterized in that, The winding fixture includes a connecting plate and a support plate. The support plate is vertically fixed to one end of the connecting plate to form an L-shaped structure. A snap-fit ​​groove is provided on the side of the connecting plate away from the support plate. The extension direction of the snap-fit ​​groove is consistent with the extension direction of the connecting plate. The corresponding first outer dividing support strip or the second innermost support support strip is disposed in the snap-fit ​​groove. The upper end face of the support plate is horizontally disposed to support the first outer layer coil or the second inner layer coil above. The tightening band is sleeved on the connecting plate of the multiple winding fixtures arranged in a ring.

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