Single column packaged single phase autotransformer

Abstract

The application discloses a single-column nested single-phase autotransformer, which comprises two side columns, a center column arranged between the two side columns, and low-voltage coils, common coils, series coils and voltage-regulating coils which are sequentially arranged outside the center column from inside to outside, wherein the side columns are not provided with coils; the common coils, the voltage-regulating coils and the series coils are sequentially connected in series. In the application, the voltage-regulating coils are arranged outside the center column, the excitation coils are cancelled, and a large amount of manufacturing cost is saved; meanwhile, the side columns on both sides of the center column are not wound with any coils and are only used for magnetic circuits, the side columns on both sides are symmetrically arranged, the center of gravity is stable, and the body is stable. In this way, the side columns are only used for magnetic circuits, so the side columns are not disturbed by other coils. The center distance of the center column to the two side columns is equal, and the length of the whole iron core is greatly reduced; the excitation coils are cancelled, the amount of the iron core silicon steel sheets is reduced, and the no-load loss of the product is reduced.

Description

[0001] Application areas

[0002] This invention relates to the field of transformer design, and in particular to a single-phase autotransformer with a single-column assembly. Background Technology

[0003] 500kV single-phase autotransformers mainly use a single-phase three-limb core. The single-phase three-limb core includes, from the inside out, a low-voltage coil, a common coil, and a series coil, all mounted sequentially on the central core column, along with side columns on both sides of the core. To ensure that the impedance of the transformer's most positive and most negative taps deviates little from the rated tap impedance, a voltage regulating coil is typically installed on the side column. This voltage regulating coil is achieved by adding an excitation coil around the side column to enhance the induced electromotive force at both ends, thus fulfilling its intended function.

[0004] This method has many problems. First, the distance from the central column to the two side columns is not equal, which makes the center of gravity easy to shift. Second, the magnetic circuit is disturbed because the voltage regulating coil and the excitation coil are wound on the side columns. Finally, the addition of the excitation coil, which is only used to cooperate with the voltage regulating coil, increases the amount of copper used, resulting in increased cost and low cost performance.

[0005] Therefore, the inventors considered moving the voltage regulating coil from the side column to the core column. This would not only prevent the magnetic flux on the side column from being disturbed, but also eliminate the need for the excitation coil. However, this would require solving many problems, such as the placement of the voltage regulating coil, low-voltage coil, common coil, and series coil after the transfer, as well as the insulation method and the outgoing wire method. Summary of the Invention

[0006] This invention overcomes the shortcomings of existing single-phase autotransformers, such as high cost and unstable center of gravity, and provides a single-column-mounted single-phase autotransformer. To achieve the above objective, the technical solution adopted by this invention is as follows: a single-column-mounted single-phase autotransformer, comprising: two side columns, a core column disposed between the two side columns, and a low-voltage coil, a common coil, a series coil, and a voltage regulating coil wound sequentially from the inside to the outside of the core column; the side columns do not have coils; the common coil, the voltage regulating coil, and the series coil are connected in series.

[0007] In a preferred embodiment of the present invention, an upper yoke is fixedly disposed at the top of the core column, and the upper yoke is electrically connected to the core column; a lower yoke is disposed at the bottom of the core column, and the core column is electrically connected to the lower yoke; an upper magnetic shielding plate is disposed at the top of the voltage regulating coil, and the upper magnetic shielding plate is electrically connected to the upper yoke; a lower magnetic shielding plate is disposed at the bottom of the coil, and the lower magnetic shielding plate is electrically connected to the lower yoke.

[0008] In a preferred embodiment of the present invention, the top of the series coil is provided with a series electrostatic plate, a plurality of series segmented corner rings and a series end insulation structure, wherein the series end insulation structure is stacked with the series segmented corner rings.

[0009] In a preferred embodiment of the present invention, the top of the voltage regulating coil is provided with a first electrostatic plate, a first split corner ring and a first end insulation structure, wherein the first split corner ring and the first end insulation structure are stacked.

[0010] The bottom of the voltage regulating coil is provided with a second electrostatic plate, a second segmented corner ring, and a second end insulation structure; the end insulation structure is stacked with the segmented corner ring.

[0011] In a preferred embodiment of the present invention, an insulating cylinder is provided on the outside of the voltage regulating coil, and a first support plate is provided between the top of the insulating cylinder and the first electrostatic plate. The first support plate includes a plurality of insulating rods arranged in parallel, and a connecting rod for fixing the insulating rods and arranged perpendicularly to the insulating rods. A first connecting hole is preset at the center of the first support plate, one side of the first connecting hole is the first electrostatic plate, and the other side of the first connecting hole is the insulating cylinder.

[0012] A second support plate is provided between the bottom of the insulating cylinder and the second electrostatic plate. The second support plate includes a plurality of insulating rods arranged in parallel and a connecting rod for fixing the insulating rods and arranged perpendicular to the insulating rods. A second connecting hole is preset at the center of the second support plate. The second electrostatic plate is on one side of the second connecting hole and the insulating cylinder is on the other side of the second connecting hole.

[0013] In a preferred embodiment of the present invention, a copper tube is provided outside the end of the series coil.

[0014] In a preferred embodiment of the present invention, the voltage regulating coil includes a first voltage regulating coil wound on the upper half of the series coil and a second voltage regulating coil wound on the lower half of the series coil. The first voltage regulating coil and the second voltage regulating coil are connected in parallel by a copper rod. A first insulating member is provided at both ends of the first voltage regulating coil, a corner ring insulating assembly is provided between the first voltage regulating coil and the second voltage regulating coil, and a second insulating member is provided at both ends of the second voltage regulating coil.

[0015] In a preferred embodiment of the present invention, the corner ring insulation assembly includes an inner corner ring, an outer corner ring, a separator cylinder, and a tensioning cylinder. The outer corner ring includes an outer flat ring fixed inside the series coil and an outer cylinder extending outward from the series coil to the outside of the voltage regulating coil. The inner corner ring includes an inner flat ring located between the outer flat ring and the series coil and an inner cylinder located inside the outer cylinder. The outer corner ring is formed by a plurality of segmented corner rings, and the inner corner ring is formed by a plurality of segmented corner rings. The inner corner ring is fixed into a ring by a tensioning cylinder inserted inside the inner cylinder and an outer corner ring clamped to the outer wall of the inner cylinder. A separator cylinder is provided between the outer cylinder and the inner cylinder.

[0016] In a preferred embodiment of the present invention, the series coil includes a first series coil wound on the upper half of the common coil and a second series coil wound on the lower half of the common coil. The first series coil and the second series coil are connected in parallel. The first lead-out end of the first series coil is led out through the inner cylinder, and the last lead-out end of the first series coil is located at the top of the first voltage regulating coil. The first lead-out end of the second series coil is led out through the inner cylinder, and the last lead-out end of the second series coil is located at the bottom of the second voltage regulating coil.

[0017] In a preferred embodiment of the present invention, an arc-shaped screen is provided between the voltage regulating coil and the side column, and the screen is attached to the outside of the voltage regulating coil.

[0018] This invention addresses the shortcomings of the prior art and has the following beneficial effects:

[0019] (1) In this invention, the voltage regulating coil is placed on the outside of the core column, eliminating the excitation coil and saving a lot of manufacturing costs. At the same time, no coils are wound on the side columns on both sides of the core column. The side columns on both sides are symmetrically arranged, resulting in a stable center of gravity and a stable device body. In addition, the side columns are only used for the magnetic circuit and will not be affected by interference from other coils.

[0020] (2) The center distance between the central column and the two side columns of the present invention is equal, and the length of the entire iron core is greatly reduced. While eliminating the excitation coil, the amount of silicon steel sheets used in the iron core is also reduced, thus reducing the no-load loss of the product. Attached Figure Description

[0021] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other embodiments can be obtained from these drawings without creative effort.

[0022] Figure 1 This is a schematic diagram of the coil assembly of a single-column-mounted single-phase autotransformer according to an embodiment of the present invention;

[0023] Figure 2 This is a schematic diagram of the coil connection principle of a single-phase autotransformer with a single column assembly according to an embodiment of the present invention;

[0024] Figure 3 This is a schematic diagram of the magnetic shielding structure of a single-phase autotransformer with a single column assembly, as described in one embodiment of the present invention.

[0025] Figure 4 This is a schematic diagram of the insulation structure of a single-phase autotransformer with a single column assembly, as described in one embodiment of the present invention.

[0026] Figure 5 This is a schematic diagram of the cooperation between the support plate and the insulating cylinder of a single-phase autotransformer with a single column assembly according to an embodiment of the present invention;

[0027] Figure 6 This is a schematic diagram of the coil distribution of a single-phase autotransformer with a single column assembly according to an embodiment of the present invention;

[0028] Figure 7 This is a schematic diagram of the support plate of a single-column set single-phase autotransformer according to one embodiment of the present invention.

[0029] The reference numerals in the attached diagram are explained as follows: 101, Side column; 102, Core column; 103, Low-voltage coil (LV); 104, Common coil (MV); 105, Series coil (HV); 1051, First series coil; 1052, Second series coil; 106, Voltage regulating coil (TV); 1061, First voltage regulating coil; 1062, Second voltage regulating coil; 107, Copper tube; 108, Upper yoke; 109, Upper magnetic shield; 110, Enclosure; 2011, First electrostatic plate; 2012, ... 1. Split corner ring; 2013. First end insulation structure; 2014. Insulating cylinder; 202. Corner ring insulation assembly; 2021. Inner corner ring; 20211. Inner cylinder body; 2022. Outer corner ring; 2023. Separating cylinder; 2024. Supporting cylinder; 2031. Second electrostatic plate; 2032. Second split corner ring; 2041. Series electrostatic plate; 2042. Series end insulation structure; 2043. Series split corner ring; 205. Support plate; 2051. Insulating rod; 2052. Connecting rod. Detailed Implementation

[0030] To better understand the above-mentioned objectives, features, and advantages of the present invention, the present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments. These drawings are simplified schematic diagrams, which only illustrate the basic structure of the present invention in a schematic manner. Therefore, they only show the components related to the present invention. It should be noted that, unless otherwise specified, the embodiments and features in the embodiments of this application can be combined with each other.

[0031] To facilitate understanding of the present invention, a more complete description will be given below with reference to the accompanying drawings. Preferred embodiments of the invention are shown in the drawings. However, the invention can be implemented in many different forms and is not limited to the embodiments described herein. Rather, these embodiments are provided to provide a thorough and complete understanding of the disclosure of the invention.

[0032] like Figure 1 As shown, a single-column single-phase autotransformer includes: two side columns 101, a core column 102 disposed between the two side columns 101, and a low-voltage coil 103, a common coil 104, a series coil 105, and a voltage regulating coil 106 wound sequentially from the inside to the outside of the core column 102. The side columns 101 do not have coils. (Refer to...) Figure 2 As shown, the common coil 104, the voltage regulating coil 106, and the series coil 105 are connected in series in sequence.

[0033] In this invention, the reference Figure 1 By placing the voltage regulating coil 106 on the outside of the core column 102, the excitation coil is eliminated, saving significant manufacturing costs. Simultaneously, no coils are wound on the side columns 101 on either side of the core column 102; they are used solely for the magnetic path. The symmetrical arrangement of the side columns 101 ensures a stable center of gravity and overall stability of the device. In this way, the side columns 101 are used solely for the magnetic path and are therefore unaffected by interference from other coils. Furthermore, the center distance between the core column 102 and the two side columns 101 is equal, greatly reducing the overall length of the core. Eliminating the excitation coil also reduces the amount of silicon steel sheets used in the core, lowering the no-load loss of the product.

[0034] Continue to refer to Figure 1 As shown, in one embodiment of the present invention, a copper tube 107 is provided outside the lead wire outlet of the series coil 105. The copper tube 107 here is only used for lead wire shielding. It should be noted that if the series coil 105 consists of multiple coils, then a copper tube 107 is provided outside the lead wire outlet of each coil.

[0035] like Figure 3As shown, an upper yoke 108 is fixedly installed at the top of the core column 102, and the upper yoke 108 is electrically connected to the core column 102; a lower yoke (a mirror image of the upper yoke 108, not shown in the figure) is installed at the bottom of the core column 102, and the core column 102 is electrically connected to the lower yoke; an upper magnetic shielding plate 109 is installed at the top of the voltage regulating coil 106, and the upper magnetic shielding plate 109 is electrically connected to the upper yoke 108; a lower magnetic shielding plate (a mirror image of the upper magnetic shielding plate 109, not shown in the figure) is installed at the bottom of the coil, and the lower magnetic shielding plate is electrically connected to the lower yoke. Here, the upper magnetic shielding plate 109 and the lower magnetic shielding plate are mainly set to shield leakage magnetic flux, and both the upper magnetic shielding plate 109 and the lower magnetic shielding plate are electrically connected to the core column 102 through the yoke, so leakage magnetic flux can be introduced into the core column 102, avoiding losses caused by leakage magnetic flux, and at the same time strengthening the magnetic flux of the core column 102. The upper yoke 108 and the lower yoke both have T-shaped cross-sections in the vertical direction, which ensures that as much coil leakage flux as possible is conducted to the core through the magnetic shielding of the core, further reducing stray losses caused by leakage flux. Figure 1 As shown, an arc-shaped screen 110 is provided between the voltage regulating coil 106 and the side post 101. The screen 110 is attached to the outside of the voltage regulating coil 106 to increase the electrical strength of the voltage regulating coil 106 to the side post.

[0036] Generally, the low-voltage coil 103, common coil 104, and series coil 105 are sequentially mounted on the central core 102 from the inside out. The common coil 104 is equivalent to a medium-voltage coil, and it is connected in series with the series coil 105 to form a high-voltage coil. Therefore, placing the series coil 105 on the outermost layer makes the insulation structure relatively simple and easy to operate. However, this invention also winds a voltage regulating coil 106 around the outside of the series coil 105, providing a new insulation structure when the original insulation structure is inconvenient to use.

[0037] like Figure 4 As shown, the top of the series coil 105 is provided with a series electrostatic plate 2041, several series split corner rings 2043, and a series end insulation structure 2042. The series end insulation structure 2042 and the series split corner rings 2043 are stacked. The bottom of the series coil 105 is also provided with a series electrostatic plate 2041, several series split corner rings 2043, and a series end insulation structure 2042. The series end insulation structure 2042 and the series split corner rings 2043 are stacked. The insulation components at the top and bottom of the series coil 105 are arranged in a mirror symmetrical manner.

[0038] Continue to refer to Figure 4As shown in the figure, a first static plate 2011, a first split angle ring 2012, and a first end insulation structure 2013 are provided at the top of the voltage regulating coil 106. The first split angle ring 2012 and the first end insulation structure 2013 are stacked; a second static plate 2031, a second split angle ring 2032, and a second end insulation structure are provided at the bottom of the voltage regulating coil 106; the end insulation structure and the split angle ring are stacked. The static plate is provided here to improve the end electric field of the coil and enhance the electrical strength.

[0039] As shown in the figure Figure 4-6 As shown in the figure, an insulating cylinder 2014 is provided outside the voltage regulating coil 106. A first support plate 205 is provided between the top of the insulating cylinder 2014 and the first static plate 2011. The first support plate 205 includes a plurality of insulating rods 2051 arranged in parallel, and a connecting rod 2052 for fixing the insulating rods 2051 and perpendicular to the insulating rods 2051. A first connection hole is preset at the center position of the first support plate 205. One side of the first connection hole is the first static plate 2011, and one side of the first connection hole is the insulating cylinder 2014; a second support plate 205 is provided between the bottom of the insulating cylinder 2014 and the second static plate 2031. The second support plate 205 includes a plurality of insulating rods 2051 arranged in parallel, and a connecting rod 2052 for fixing the insulating rods 2051 and perpendicular to the insulating rods 2051. A second connection hole is preset at the center position of the second support plate 205. One side of the second connection hole is the second static plate 2031, and one side of the second connection hole is the insulating cylinder 2014. Here, in addition to their own insulating functions, the insulating cylinder 2014, the first support plate 205, and the first split angle ring 2012 can also support the voltage regulating coil 106 to ensure the stability of the device. Since the insulating cylinder 2014 needs to support the voltage regulating coil 106 and at the same time leave a position for the series connection lead-out, it must have a certain strength. In the present invention, the insulating cylinder 2014 is made of three layers of 5-mm thick extra-hard paper tubes riveted with the corresponding first support plate 205.

[0040] As shown in the figure Figure 7 As shown in the figure, for the convenience of the series connection lead-out of the series coil 105, the voltage regulating coil 106 of the present invention includes a first voltage regulating coil 1061 wound around the upper half of the series coil 105 and a second voltage regulating coil 1062 wound around the lower half of the series coil 105. The first voltage regulating coil 1061 and the second voltage regulating coil 1062 are connected in parallel through a copper bar; the insulating components described above are provided at the top of the first voltage regulating coil 1061, a corner ring insulating component 202 is provided between the first voltage regulating coil 1061 and the second voltage regulating coil 1062, and the insulating components described above are provided at the bottom of the second voltage regulating coil 1062. It should be noted that the insulating components of the first voltage regulating coil 1061 and the insulating components of the second voltage regulating coil 1062 are arranged in mirror symmetry.

[0041] Specifically, the corner ring insulation assembly 202 includes an inner corner ring 2021, an outer corner ring 2022, a separator cylinder 2023, and a tensioning cylinder 2024. The outer corner ring 2022 includes an outer flat ring fixed inside the series coil 105 and an outer cylinder extending outward from the series coil 105 to the outside of the voltage regulating coil 106. The inner corner ring 2021 includes an inner flat ring located between the outer flat ring and the series coil 105 and an inner cylinder 20211 located inside the outer cylinder. The outer corner ring 2022 is composed of several segmented corner rings, and the inner corner ring 2021 is composed of several segmented corner rings. The inner corner ring 2021 is fixed into a ring by the tensioning cylinder 2024 inserted inside the inner cylinder 20211 and the outer corner ring 2022 clamped to the outer wall of the inner cylinder 20211. A separator cylinder 2023 is provided between the outer cylinder and the inner cylinder 20211. The outer cylinder is insulated and tightened by crepe paper.

[0042] Continue to refer to Figure 7 As shown, the series coil 105 includes a first series coil 1051 wound on the upper half of the common coil 104 and a second series coil 1052 wound on the lower half of the common coil 104. The first series coil 1051 and the second series coil 1052 are connected in parallel. The first lead-out end of the first series coil 1051 is led out through the inner cylinder 20211, and the last lead-out end of the first series coil 1051 is located at the top of the first voltage regulating coil 1061. The lead-out end of the first series coil 1051 leads out from the top of the first voltage regulating coil 1061, which can improve the lead electric field at the lead-out end and increase the creepage distance from the lead-out end to the low potential. The first lead-out end of the second series coil 1052 is led out through the inner cylinder 20211, and the last lead-out end of the second series coil 1052 is located at the bottom of the second voltage regulating coil 1062. In other words, the first lead-out end of the first series coil 1051 and the first lead-out end of the second series coil 1052 are both led out from the inside of the inner corner ring 2021, and the insulation between the first voltage regulating coil 1061 and the second voltage regulating coil 1062 is achieved through the corner ring insulation component 202.

[0043] Reference Figure 7 As shown, the second insulating member at the bottom of the second voltage regulating coil 1062 is symmetrically arranged with the first insulating component. The arrangement structure here is symmetrical with the structure related to the first voltage regulating coil 1061, and the corresponding components have the same function.

[0044] The main purpose of this invention is to reduce transformer costs as much as possible while ensuring transformer performance parameters. Compared with existing technologies, it not only saves on the amount of copper, silicon steel sheets, transformer oil, and insulation components, but also appropriately reduces transformer losses.

[0045] Because the voltage regulating coil 106 has fewer turns and is lighter in weight, both the upper and lower parts of the voltage regulating coil 106 need to be wound together on the insulating cylinder 2014 for easy assembly. This requires the use of a vertical winding machine. Additionally, during the winding of the voltage regulating coil 106, due to the large number of insulating components, attention must be paid to preventing the coil winding height from exceeding tolerances. If necessary, the insulating components should be pre-dried in an oven.

[0046] The above embodiments merely illustrate several implementation methods of the present invention, and their descriptions are relatively specific and detailed, but they should not be construed as limiting the scope of the invention patent. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of the present invention, and these all fall within the protection scope of the present invention. Therefore, the protection scope of this invention patent should be determined by the appended claims.

Claims

1. A single-column-mounted single-phase autotransformer, characterized in that, include: The system comprises two side columns, a core column positioned between the two side columns, and a low-voltage coil, a common coil, a series coil, and a voltage regulating coil wound sequentially from the inside out around the core column. The side columns do not have coils. The common coil and the voltage regulating coil are connected in series. The top of the voltage regulating coil is provided with a first electrostatic plate, a first segmented corner ring, and a first end insulation structure, wherein the first segmented corner ring and the first end insulation structure are stacked together. The bottom of the voltage regulating coil is provided with a second electrostatic plate, a second segmented corner ring, and a second end insulation structure; the end insulation structure is stacked with the segmented corner ring. An insulating cylinder is provided on the outside of the voltage regulating coil. A first support plate is provided between the top of the insulating cylinder and the first electrostatic plate. The first support plate includes a plurality of insulating rods arranged in parallel and a connecting rod for fixing the insulating rods and arranged perpendicular to the insulating rods. A first connecting hole is preset at the center of the first support plate. The first electrostatic plate is on one side of the first connecting hole and the insulating cylinder is on the other side of the first connecting hole. A second support plate is provided between the bottom of the insulating cylinder and the second electrostatic plate. The second support plate includes a plurality of insulating rods arranged in parallel and a connecting rod for fixing the insulating rods and arranged perpendicular to the insulating rods. A second connecting hole is preset at the center of the second support plate. The second electrostatic plate is on one side of the second connecting hole and the insulating cylinder is on the other side of the second connecting hole. The voltage regulating coil includes a first voltage regulating coil wound on the upper half of the series coil and a second voltage regulating coil wound on the lower half of the series coil. The first voltage regulating coil and the second voltage regulating coil are connected in parallel through a copper rod. A first insulating element is provided at both ends of the first voltage regulating coil, and a corner ring insulating assembly is provided between the first voltage regulating coil and the second voltage regulating coil. A second insulating element is provided at both ends of the second voltage regulating coil. The corner ring insulation assembly includes an inner corner ring, an outer corner ring, a separator cylinder, and a tensioning cylinder. The outer corner ring includes an outer flat ring fixed inside the series coil and an outer cylinder extending outward from the series coil to the outside of the voltage regulating coil. The inner corner ring includes an inner flat ring located between the outer flat ring and the series coil and an inner cylinder located inside the outer cylinder. The outer corner ring is composed of several segmented corner rings, and the inner corner ring is composed of several segmented corner rings. The inner corner ring is fixed into a ring by a tensioning cylinder inserted inside the inner cylinder and an outer corner ring clamped to the outer wall of the inner cylinder. A separator cylinder is provided between the outer cylinder and the inner cylinder. The series coil includes a first series coil wound on the upper half of the common coil and a second series coil wound on the lower half of the common coil. The first series coil and the second series coil are connected in parallel. The first lead-out end of the first series coil is led out through the inner cylinder, and the last lead-out end of the first series coil is located at the top of the first voltage regulating coil. The first lead-out end of the second series coil is led out through the inner cylinder, and the last lead-out end of the second series coil is located at the bottom of the second voltage regulating coil. An arc-shaped screen is provided between the voltage regulating coil and the side column, and the screen is attached to the outside of the voltage regulating coil.

2. A single-phase autotransformer with a single-column assembly according to claim 1, characterized in that: An upper yoke is fixedly installed at the top of the core column, and the upper yoke is electrically connected to the core column; a lower yoke is installed at the bottom of the core column, and the core column is electrically connected to the lower yoke; an upper magnetic shield is installed at the top of the voltage regulating coil, and the upper magnetic shield is electrically connected to the upper yoke; a lower magnetic shield is installed at the bottom of the coil, and the lower magnetic shield is electrically connected to the lower yoke.

3. A single-phase autotransformer with a single-column assembly according to claim 1, characterized in that: The top of the series coil is provided with a series electrostatic plate, several series segmented corner rings, and a series end insulation structure, wherein the series end insulation structure is stacked with the series segmented corner rings.

4. A single-phase autotransformer with a single-column assembly according to claim 1, characterized in that: A copper tube is provided outside the end of the series coil.

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