A high voltage pancake winding of a transformer

Abstract

The present application provides a high-voltage pancake winding of a transformer, comprising: a low-voltage coil 1, an insulating barrel 2, a comb-type support bar 3, a cushion bar 4, and a high-voltage coil 5. There is a spacing a between the low-voltage coil 1 and the insulating barrel 2. The insulating barrel 2 is fixed to the comb-type support bar 3. The high-voltage coil 5 is arranged on the comb teeth of the comb-type support bar 3. A coil 51 of the high-voltage coil 5 is arranged on one comb tooth. There are multiple coils 51 of the high-voltage coil 5, and each coil is connected in series to form the high-voltage coil 5. The distance between the high-voltage coil 5 and the insulating barrel 2 is b. The cushion bar 4 is added to the head coil 51 and the tail coil 51 of the high-voltage coil 5, and the thickness of the added cushion bar 4 gradually decreases from the head coil 51 to the middle coil 51 and from the tail coil 51 to the middle coil 51, so that the spacing a between the low-voltage coil 1 and the insulating barrel 2 and the distance b between the high-voltage coil 5 and the insulating barrel 2 can be reduced, so that the core size of the transformer is reduced and the no-load loss is reduced.

Description

Technical Field

[0001] The invention relates to the technical field of thermo-electrochemical oxidation, and in particular to a high-voltage pancake winding of a transformer. Background Art

[0002] The high-voltage pancake winding of the transformer needs a certain insulation distance to operate because the high-voltage coil and the low-voltage coil are charged bodies, otherwise discharge will occur. The insulation distance between the high-voltage coil and the low-voltage coil of the traditional transformer high-voltage pancake winding is 35mm for 10KV transformers and 50mm for 35KV transformers.

[0003] Since the insulation distance between the high-voltage coil and the low-voltage coil in the prior art is relatively large, the iron core size of the transformer is relatively large, resulting in relatively large no-load losses.

[0004] In view of this, the present invention provides a high-voltage pancake winding of a transformer, which reduces the insulation distance between the high-voltage coil and the low-voltage coil, reduces the size of the transformer core, and reduces the no-load loss. Summary of the invention

[0005] The object of the present invention is to provide a high-voltage pancake winding of a transformer, which reduces the insulation distance between the high-voltage coil and the low-voltage coil, reduces the core size of the transformer, and reduces the no-load loss.

[0006] In the high-voltage coil of the high-voltage pancake winding of the prior art, each coil 51 is arranged neatly, while in the high-voltage coil of the high-voltage pancake winding of the present application, the coils 51 are arranged in a staggered manner in the radial distance, thereby reducing the insulation distance between the high-voltage coil and the low-voltage coil.

[0007] Specifically, through simulation research, the applicant found that the electric field distribution of the high-voltage coil of the high-voltage pancake-type winding is mainly concentrated in the head and tail coils 51. The closer to the head and tail coils 51, the greater the electric field strength, and the electric field strength at the middle coil 51 is weaker. That is, the insulation distance between the head and tail coils 51 of the high-voltage coil and the low-voltage coil needs to be larger, while the insulation distance between the middle coil 51 of the high-voltage coil and the low-voltage coil can actually be smaller. Therefore, the present application adds pads to the first and last coils 51 of the high-voltage coil, and the thickness of the pads gradually decreases from the first coil 51 to the middle coil 51 and from the tail coil 51 to the middle coil 51, and the number of turns 52 of the coil 51 from the first coil 51 to the middle coil 51 and from the tail coil 51 to the middle coil 51 gradually increases, so that the electric field strength at the first and last parts of the high-voltage coil is the same as that in the middle part, and the main body size of the high-voltage coil remains unchanged, thereby reducing the insulation distance between the high-voltage coil and the low-voltage coil. The reduction in insulation distance reduces the size of the transformer core, thereby reducing the no-load loss. The present applicant completes the present application on this basis.

[0008] A high-voltage pancake winding of a transformer comprises: a low-voltage coil 1, an insulating barrel 2, a comb-type stay 3, a cushion bar 4, and a high-voltage coil 5. There is a spacing a between the low-voltage coil 1 and the insulating barrel 2. The insulating barrel 2 is fixed to the comb-type stay 3. The high-voltage coil 5 is arranged on the comb teeth of the comb-type stay 3. A coil 51 of the high-voltage coil 5 is arranged on one comb tooth. There are multiple coils 51 of the high-voltage coil 5, and each coil is connected in series to form the high-voltage coil 5. The distance between the high-voltage coil 5 and the insulating barrel 2 is b. The cushion bar 4 is added to the head coil 51 and the tail coil 51 of the high-voltage coil 5. The thickness of the added cushion bar 4 gradually decreases from the head coil 51 to the middle coil 51 and from the tail coil 51 to the middle coil 51. The cushion bar 4 is an insulator, so that the spacing a between the low-voltage coil 1 and the insulating barrel 2 and the distance b between the high-voltage coil 5 and the insulating barrel 2 can be reduced, so that the iron core size of the transformer is reduced and the no-load loss is reduced.

[0009] In some embodiments, the number of coils 51 of the high-voltage coil 5 is 12-16, the voltages of each coil 51 are added together to output the voltage, and a transverse airway is provided between two adjacent coils 51 for heat dissipation, and the distance of the transverse airway is 3-12 mm.

[0010] Furthermore, the coil 51 of the high-voltage coil 5 is composed of a plurality of turns 52 , each of the turns 52 is connected in series, and no air passage is provided between two adjacent turns 52 .

[0011] Furthermore, the distance between the high-voltage coil and the low-voltage coil is the insulation distance, which is composed of the sum of the spacing a between the low-voltage coil 1 and the insulating barrel 2, the distance b between the high-voltage coil 5 and the insulating barrel 2, and the outer diameter of the insulating barrel 2. The outer diameter of the insulating barrel 2 remains unchanged, and the electric field strength at the head and tail of the high-voltage coil is the same as the electric field strength in the middle, thereby reducing the spacing a between the low-voltage coil 1 and the insulating barrel 2 and the distance b between the high-voltage coil 5 and the insulating barrel 2, that is, reducing the insulation distance between the high-voltage coil and the low-voltage coil.

[0012] Furthermore, the number of turns 52 of the coil 51 gradually increases from the head end coil 51 to the middle coil 51 and from the tail end coil 51 to the middle coil 51, keeping the size of each coil 51 of the high-voltage coil 5 the same, so that the main body size of the high-voltage coil remains unchanged.

[0013] Furthermore, the insulation distance between the high-voltage coil and the low-voltage coil is reduced and the size of the high-voltage coil body remains unchanged, so the outer diameter of the high-voltage coil becomes smaller, thereby reducing the core size of the transformer. When the core size is reduced, the no-load loss is reduced.

[0014] Since the total number of turns of the entire high-voltage coil divided by the number of turns per coil is generally not an integer, there will always be a few coils 51 of the high-voltage coil with a smaller number of turns 52. Therefore, the present application cleverly arranges the coils 51 with a smaller number of turns 52 at the head and tail. Therefore, although pads 4 are added to the head coil 51 and the tail coil 51 of the high-voltage coil 5, and the thickness of the added pads 4 gradually decreases from the head coil 51 to the middle coil 51 and from the tail coil 51 to the middle coil 51, the size of each coil 51 of the high-voltage coil 5 can be kept the same, so that the overall size of the high-voltage coil remains unchanged.

[0015] Furthermore, when 6 mm padding strips 4 are added to the first end wire coil 51 and the tail end wire coil 51, 4 mm padding strips 4 are added to the second wire coil 51 and the second to last wire coil 51 of the high-voltage coil 5, 2 mm padding strips 4 are added to the third wire coil 51 and the third to last wire coil 51 of the high-voltage coil 5, and no padding strips 4 are added to the remaining middle wire coils 51 of the high-voltage coil 5, the sum of the distance a between the low-voltage coil 1 and the insulating barrel 2 and the distance b between the high-voltage coil 5 and the insulating barrel 2, a and b, is reduced by 6 mm.

[0016] For example, for a 10KV transformer, the traditional insulation distance from the high-voltage coil to the low-voltage coil is 35mm. The present application adds 6mm pads inside the first and last end coils, 4mm pads inside the second coil 51 and the second-to-last coil 51, 2mm pads inside the third coil 51 and the third-to-last coil 51, and no pads are added to the remaining coils 51, so that the spacing a between the low-voltage coil 1 and the insulating barrel 2 and the distance b between the high-voltage coil 5 and the insulating barrel 2 are respectively reduced by 3mm. The insulation distance from the high-voltage coil to the low-voltage coil of the present application is 29mm, which reduces the size of the transformer core by 5%, and the no-load loss of the transformer is also reduced by 5%.

[0017] For example, for a 35KV transformer, the traditional insulation distance from the high-voltage coil to the low-voltage coil is 50mm. The present application adds 6mm pads inside the first and last end coils, 4mm pads inside the second coil 51 and the second-to-last coil 51, 2mm pads inside the third coil 51 and the third-to-last coil 51, and no pads are added to the remaining coils 51, so that the distance a between the low-voltage coil 1 and the insulating barrel 2 and the distance b between the high-voltage coil 5 and the insulating barrel 2, the sum of a and b is reduced by 6mm. The insulation distance from the high-voltage coil to the low-voltage coil of the present application is 44mm, which reduces the size of the transformer core by 5%, and the no-load loss of the transformer is also reduced by 5%.

[0018] Furthermore, the wire of the first end coil 51 of the high-voltage coil 5 is wound from left to right, the wire of the second coil 51 is wound from right to left, the wire of the third coil 51 is wound from left to right, and so on.

[0019] In some embodiments, the number of layers of the low-voltage coil 1 is 2-4, each layer of the low-voltage coil 1 is connected in series, and there is an air channel between two layers of the low-voltage coil 1, and the distance of the air channel is 10-12 mm.

[0020] Furthermore, the first layer of the wires of the low voltage coil 1 are wound from top to bottom, the second layer of the wires are wound from bottom to top, the third layer of the wires are wound from top to bottom, and so on.

[0021] In some embodiments, the insulating barrel 2 is a hollow cylinder, and the insulating barrel 2 and the comb-type struts 3 are fixed by silicone. The insulating barrel 2 plays the role of insulation and fixed support of the comb-type struts 3. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Combined with the following Figure 1When read together, the above and other features of the present application will be more fully described. It is understood that these drawings only depict several implementations of the present application and should not be considered as limiting the scope of the present application. By using the drawings, the present application will be more clearly and detailed.

[0023] Figure 1 This is a schematic diagram of the structure of the high-voltage pancake winding of the transformer of the present application.

[0024] Description of main component symbols:

[0025] Low-voltage coil 1, insulating barrel 2, comb-type support bar 3, cushion bar 4, high-voltage coil 5, wire cake 51, wire turn 52. DETAILED DESCRIPTION

[0026] The following examples are described to assist the understanding of the present application, and the examples are not and should not be interpreted in any way as limiting the scope of protection of the present application.

[0027] In the following description, those skilled in the art will recognize that throughout this discussion, components may be described as separate functional units (which may include sub-units), but those skilled in the art will recognize that various components or portions thereof may be divided into separate components or may be integrated together (including within a single system or component).

[0028] Embodiment 1:

[0029] A high voltage pancake winding of a transformer, such as Figure 1 As shown, it includes: a low-voltage coil 1, an insulating barrel 2, a comb-type support bar 3, a pad 4, and a high-voltage coil 5. There is a spacing a between the low-voltage coil 1 and the insulating barrel 2. The insulating barrel 2 is fixed to the comb-type support bar 3. The high-voltage coil 5 is arranged on the comb teeth of the comb-type support bar 3. A wire coil 51 of the high-voltage coil 5 is arranged on one comb tooth. There are multiple wire coils 51 of the high-voltage coil 5, and each wire coil is connected in series to form the high-voltage coil 5. The distance between the high-voltage coil 5 and the insulating barrel 2 is b. The pad 4 is added to the head wire coil 51 and the tail wire coil 51 of the high-voltage coil 5, and the thickness of the added pad 4 is gradually reduced from the head wire coil 51 to the middle wire coil 51 and from the tail wire coil 51 to the middle wire coil 51, so that the spacing a between the low-voltage coil 1 and the insulating barrel 2 and the distance b between the high-voltage coil 5 and the insulating barrel 2 can be reduced, so that the core size of the transformer is reduced and the no-load loss is reduced.

[0030] The transformer is a 10KV transformer (the conventional insulation distance from the high-voltage coil to the low-voltage coil is 35mm). A 6mm gasket is added inside the wire coils 51 of the first and last coils, a 4mm gasket is added inside the second wire coil 51 and the second-to-last wire coil 51, a 2mm gasket is added inside the third wire coil 51 and the third-to-last wire coil 51, and no gasket is added inside the remaining middle wire coils 51, so that the distance a between the low-voltage coil 1 and the insulating barrel 2 and the distance b between the high-voltage coil 5 and the insulating barrel 2, the sum of a and b is reduced by 6mm, the insulation distance from the high-voltage coil to the low-voltage coil is 29mm, the size of the transformer core is reduced by 5%, and the no-load loss of the transformer is also reduced by 5%.

[0031] The number of coils 51 of the high-voltage coil 5 is 14, and the voltage of each coil 51 is added together to output the voltage. A transverse airway is provided between two adjacent coils 51, and the transverse airway is used for heat dissipation, and the distance of the transverse airway is 10 mm. The coil 51 of the high-voltage coil 5 is composed of a plurality of turns 52, each of which is connected in series, and no airway is provided between two adjacent turns 52. The distance between the high-voltage coil and the low-voltage coil is the insulation distance, and the insulation distance is composed of the spacing a between the low-voltage coil 1 and the insulating barrel 2, the distance b between the high-voltage coil 5 and the insulating barrel 2, and the outer diameter of the insulating barrel 2. The outer diameter of the insulating barrel 2 remains unchanged, and the electric field strength at the head and tail of the high-voltage coil is the same as the electric field strength in the middle, thereby reducing the spacing a between the low-voltage coil 1 and the insulating barrel 2 and the distance b between the high-voltage coil 5 and the insulating barrel 2, that is, reducing the insulation distance between the high-voltage coil and the low-voltage coil.

[0032] The number of turns 52 of the first end coil 51 and the tail end coil 51 is reduced by 3 turns compared with the number of turns 52 of the middle coil 51, the number of turns 52 of the second coil 51 and the second to last coil 51 is reduced by 2 turns compared with the number of turns 52 of the middle coil 51, and the number of turns 52 of the third coil 51 and the third to last coil 51 is reduced by 1 turn compared with the number of turns 52 of the middle coil 51, and the size of each coil 51 of the high-voltage coil 5 is kept the same, so that the body size of the high-voltage coil remains unchanged. The insulation distance between the high-voltage coil and the low-voltage coil is reduced and the body size of the high-voltage coil remains unchanged, so the outer diameter of the high-voltage coil becomes smaller, thereby reducing the core size of the transformer. When the core size is reduced, the no-load loss is reduced. Since the total number of turns of the entire high-voltage coil divided by the number of turns per coil is generally not an integer, there will always be a few coils 51 of the high-voltage coil with a smaller number of turns 52. Therefore, the present application cleverly arranges the coils 51 with a smaller number of turns 52 at the head and tail. Therefore, although pads 4 are added to the head coil 51 and the tail coil 51 of the high-voltage coil 5, and the thickness of the added pads 4 gradually decreases from the head coil 51 to the middle coil 51 and from the tail coil 51 to the middle coil 51, the size of each coil 51 of the high-voltage coil 5 can be kept the same, so that the overall size of the high-voltage coil remains unchanged.

[0033] The wire of the first end coil 51 of the high-voltage coil 5 is wound from left to right, the wire of the second coil 51 is wound from right to left, the wire of the third coil 51 is wound from left to right, and so on. The low-voltage coil 1 has three layers, and each layer of the low-voltage coil 1 is connected in series. There is an airway between the two layers of the low-voltage coil 1, and the distance of the airway is 10 mm. The wire of the first layer of the low-voltage coil 1 is wound from top to bottom, the wire of the second layer is wound from bottom to top, the wire of the third layer is wound from top to bottom, and so on. The insulating barrel 2 is a hollow cylinder, and the insulating barrel 2 is fixed to the comb-type strut 3 by silicone. The insulating barrel 2 plays the role of insulation and fixed support of the comb-type strut 3.

[0034] Embodiment 2:

[0035] A high voltage pancake winding of a transformer, such as Figure 1As shown, it includes: a low-voltage coil 1, an insulating barrel 2, a comb-type support bar 3, a pad 4, and a high-voltage coil 5. There is a spacing a between the low-voltage coil 1 and the insulating barrel 2. The insulating barrel 2 is fixed to the comb-type support bar 3. The high-voltage coil 5 is arranged on the comb teeth of the comb-type support bar 3. A wire coil 51 of the high-voltage coil 5 is arranged on one comb tooth. There are multiple wire coils 51 of the high-voltage coil 5, and each wire coil is connected in series to form the high-voltage coil 5. The distance between the high-voltage coil 5 and the insulating barrel 2 is b. The pad 4 is added to the head wire coil 51 and the tail wire coil 51 of the high-voltage coil 5, and the thickness of the added pad 4 is gradually reduced from the head wire coil 51 to the middle wire coil 51 and from the tail wire coil 51 to the middle wire coil 51, so that the spacing a between the low-voltage coil 1 and the insulating barrel 2 and the distance b between the high-voltage coil 5 and the insulating barrel 2 can be reduced, so that the core size of the transformer is reduced and the no-load loss is reduced.

[0036] The transformer is a 35KV transformer. The traditional insulation distance from the high-voltage coil to the low-voltage coil is 50mm. The present application adds 6mm pads inside the first and tail end coils, adds 4mm pads inside the second coil 51 and the second-to-last coil 51, adds 2mm pads inside the third coil 51 and the third-to-last coil 51, and no pads are added to the remaining coils 51, so that the distance a between the low-voltage coil 1 and the insulating barrel 2 and the distance b between the high-voltage coil 5 and the insulating barrel 2, the sum of a and b is reduced by 6mm. The insulation distance from the high-voltage coil to the low-voltage coil of the present application is 44mm, so that the size of the transformer core is reduced by 5%, and the no-load loss of the transformer is also reduced by 5%.

[0037] The number of coils 51 of the high-voltage coil 5 is 14, and the voltage of each coil 51 is added together to output the voltage. A transverse airway is provided between two adjacent coils 51, and the transverse airway is used for heat dissipation. The distance of the transverse airway is 12 mm. The coil 51 of the high-voltage coil 5 is composed of a plurality of turns 52, each of which is connected in series, and no airway is provided between two adjacent turns 52. The distance between the high-voltage coil and the low-voltage coil is the insulation distance, which is composed of the distance a between the low-voltage coil 1 and the insulating barrel 2, the distance b between the high-voltage coil 5 and the insulating barrel 2, and the outer diameter of the insulating barrel 2. The outer diameter of the insulating barrel 2 remains unchanged, and the electric field strength at the head and tail of the high-voltage coil is the same as the electric field strength in the middle, thereby reducing the distance a between the low-voltage coil 1 and the insulating barrel 2 and the distance b between the high-voltage coil 5 and the insulating barrel 2, that is, reducing the insulation distance between the high-voltage coil and the low-voltage coil.

[0038] The number of turns 52 of the first end coil 51 and the tail end coil 51 is reduced by 4 turns compared with the number of turns 52 of the middle coil 51, the number of turns 52 of the second coil 51 and the second to last coil 51 is reduced by 3 turns compared with the number of turns 52 of the middle coil 51, the number of turns 52 of the third coil 51 and the third to last coil 51 is reduced by 2 turns compared with the number of turns 52 of the middle coil 51, and the number of turns 52 of the fourth coil 51 and the fourth to last coil 51 is reduced by 1 turn compared with the number of turns 52 of the middle coil 51, and the size of each coil 51 of the high-voltage coil 5 is kept the same, so that the body size of the high-voltage coil remains unchanged. The insulation distance between the high-voltage coil and the low-voltage coil is reduced and the body size of the high-voltage coil remains unchanged, so the outer diameter of the high-voltage coil becomes smaller, thereby reducing the core size of the transformer, and reducing the core size, the no-load loss is reduced. Since the total number of turns of the entire high-voltage coil divided by the number of turns per coil is generally not an integer, there will always be a few coils 51 of the high-voltage coil with a smaller number of turns 52. Therefore, the present application cleverly arranges the coils 51 with a smaller number of turns 52 at the head and tail. Therefore, although pads 4 are added to the head coil 51 and the tail coil 51 of the high-voltage coil 5, and the thickness of the added pads 4 gradually decreases from the head coil 51 to the middle coil 51 and from the tail coil 51 to the middle coil 51, the size of each coil 51 of the high-voltage coil 5 can be kept the same, so that the overall size of the high-voltage coil remains unchanged.

[0039] The wire of the first end coil 51 of the high-voltage coil 5 is wound from left to right, the wire of the second coil 51 is wound from right to left, the wire of the third coil 51 is wound from left to right, and so on. The low-voltage coil 1 has three layers, and each layer of the low-voltage coil 1 is connected in series. There is an airway between the two layers of the low-voltage coil 1, and the distance of the airway is 10 mm. The wire of the first layer of the low-voltage coil 1 is wound from top to bottom, the wire of the second layer is wound from bottom to top, the wire of the third layer is wound from top to bottom, and so on. The insulating barrel 2 is a hollow cylinder, and the insulating barrel 2 is fixed to the comb-type strut 3 by silicone. The insulating barrel 2 plays the role of insulation and fixed support of the comb-type strut 3.

[0040] Although the present application has disclosed multiple aspects and embodiments, other aspects and embodiments will be obvious to those skilled in the art, and several modifications and improvements may be made without departing from the concept of the present application, all of which belong to the protection scope of the present application. The multiple aspects and embodiments disclosed in the present application are only for illustration and are not intended to limit the present application. The actual protection scope of the present application shall be subject to the claims.

Claims

1. A high voltage pancake winding of a transformer, characterized in that: include: A low-voltage coil (1), an insulating barrel (2), a comb-type support bar (3), a pad bar (4), and a high-voltage coil (5). There is a spacing a between the low-voltage coil (1) and the insulating barrel (2). The insulating barrel (2) and the comb-type support bar (3) are fixed. The high-voltage coil (5) is arranged on the comb teeth of the comb-type support bar (3). A wire coil (51) of the high-voltage coil (5) is arranged on each comb tooth. There are multiple wire coils (51) of the high-voltage coil (5), and each coil is connected in series to form the high-voltage coil (5). The high-voltage coil (5) and the insulating barrel are connected to each other. The distance between the low-voltage coil (1) and the insulating barrel (2) is b, and a gasket (4) is added to the head coil (51) and the tail coil (51) of the high-voltage coil (5), and the thickness of the added gasket (4) gradually decreases from the head coil (51) to the middle coil (51) and from the tail coil (51) to the middle coil (51), so that the distance a between the low-voltage coil (1) and the insulating barrel (2) and the distance b between the high-voltage coil (5) and the insulating barrel (2) can be reduced, so that the core size of the transformer is reduced and the no-load loss is reduced.

2. The high voltage pancake winding of the transformer according to claim 1, characterized in that: The number of coils (51) of the high-voltage coil (5) is 12-16, the voltages of each coil (51) are added together to output a voltage, a transverse air channel is provided between two adjacent coils (51), the transverse air channel is used for heat dissipation, and the distance between the transverse air channels is 3-12 mm.

3. The high voltage pancake winding of the transformer according to claim 2, characterized in that: The coil (51) of the high-voltage coil (5) is composed of a plurality of coil turns (52), each of the coil turns (52) is connected in series, and no air passage is provided between two adjacent coil turns (52).

4. The high voltage pancake winding of the transformer according to claim 3, characterized in that: The distance between the high-voltage coil and the low-voltage coil is the insulation distance, which is composed of the distance a between the low-voltage coil (1) and the insulation barrel (2), the distance b between the high-voltage coil (5) and the insulation barrel (2), and the outer diameter of the insulation barrel (2). The outer diameter of the insulation barrel (2) remains unchanged, and the electric field strength at the front and rear ends of the high-voltage coil is the same as the electric field strength in the middle, thereby reducing the distance a between the low-voltage coil (1) and the insulation barrel (2) and the distance b between the high-voltage coil (5) and the insulation barrel (2), that is, reducing the insulation distance between the high-voltage coil and the low-voltage coil.

5. The high voltage pancake winding of the transformer according to claim 4, characterized in that: The number of turns (52) of the coils (51) gradually increases from the head end coil (51) to the middle coil (51) and from the tail end coil (51) to the middle coil (51), so that the size of each coil (51) of the high-voltage coil (5) is kept the same, thereby keeping the main body size of the high-voltage coil unchanged.

6. The high voltage pancake winding of the transformer according to claim 5, characterized in that: When a 6 mm pad (4) is added to the first end coil (51) and the tail end coil (51), a 4 mm pad (4) is added to the second coil (51) and the second to last coil (51) of the high voltage coil (5), a 2 mm pad (4) is added to the third coil (51) and the third to last coil (51) of the high voltage coil (5), and no pad (4) is added to the remaining middle coils (51) of the high voltage coil (5), the distance a between the low voltage coil (1) and the insulating barrel (2) and the distance b between the high voltage coil (5) and the insulating barrel (2), and the sum of a and b is reduced by 6 mm.

7. The high voltage pancake winding of the transformer according to claim 6, characterized in that: The conductor of the first coil (51) of the high-voltage coil (5) is wound from left to right, the conductor of the second coil (51) is wound from right to left, the conductor of the third coil (51) is wound from left to right, and so on.

8. The high voltage pancake winding of the transformer according to claim 1, characterized in that: The number of layers of the low-voltage coil (1) is 2-4, each layer of the low-voltage coil (1) is connected in series, and an air channel is provided between two layers of the low-voltage coil (1), and the distance of the air channel is 10-12 mm.

9. The high voltage pancake winding of the transformer according to claim 1, characterized in that: The insulating barrel (2) is a hollow cylinder. The insulating barrel (2) and the comb-type support bar (3) are fixed by means of silicone. The insulating barrel (2) plays the role of insulation and fixing and supporting the comb-type support bar (3).

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