Ultra-high-voltage step-up transformer with coil leads connected in series

Abstract

The present invention relates to the field of transformer lead connections. Specifically disclosed is an ultra-high-voltage step-up transformer with coil leads connected in series, comprising two iron core columns on which coils are to be sleeved, a first high-voltage coil wound on one iron core column, a second high-voltage coil wound on the other iron core column, and a connecting assembly used for connecting the first high-voltage coil to the second high-voltage coil. The first high-voltage coil and the second high-voltage coil are connected in series; the connecting assembly comprises a plurality of voltage equalizing tubes connected in sequence, connecting pieces used for connecting every two adjacent voltage equalizing tubes, and insulating pieces wound on the outer sides of the voltage equalizing tubes; and leads between the first high-voltage coil and the second high-voltage coil are arranged inside the voltage equalizing tubes. The present invention utilizes a double-column series structure; and the high-voltage coils on the two iron core columns have an equal number of turns, so that the potential of the leads is reduced, and thus the electrical insulation strength of the leads is easy to guarantee. The structure that the voltage equalizing tubes are connected by means of the leads is utilized, thereby achieving a good electrode shape, a simple structure, convenient operations, and high lead insulation reliability.

Description

A UHV step-up transformer with coil leads connected in series Technical Field

[0001] The invention belongs to the technical field of transformer lead connection, and in particular relates to an ultra-high voltage step-up transformer with coil leads connected in series. Background Art

[0002] Currently, ultra-high voltage (UHV) power transmission is experiencing sustained and rapid development. Currently, UHV and ultra-large capacity step-up transformers, which increase voltages to 1100 kV, generally utilize a two-pole parallel structure. To meet insulation requirements, parallel UHV transformers require high reactance and a high transformer body height. The two poles, except for the coil winding direction, have identical insulation structures. This heavy body weight limits their transport dimensions and weight due to operational constraints. Furthermore, the voltage between the poles is the same as the voltage at the high-voltage head end, placing very high demands on the insulation treatment of the connecting wires.

[0003] In summary, a parallel UHV step-up transformer is bulky, difficult to transport, and has difficulty guaranteeing insulation performance. A two-pole series structure is preferred. However, even though the voltage at the upper and lower ends of the first coil is half the voltage at the middle of the coil, this voltage is still very high and could pose a new quality risk if not properly handled.

[0004] Summary of the Invention

[0005] The present invention provides an ultra-high voltage step-up transformer with coil leads connected in series, which is used to solve the problems of the existing ultra-high voltage step-up transformer being bulky, difficult to transport, and difficult to ensure insulation performance.

[0006] In order to solve the above technical problems, the technical solution of the present invention is as follows: a UHV step-up transformer with coil leads connected in series, comprising: two core legs with coils, a first high-voltage coil wound on one core leg, a second high-voltage coil wound on the other core leg, and a connecting assembly for connecting the first high-voltage coil and the second high-voltage coil;

[0007] The first high-voltage coil is connected in series with the second high-voltage coil;

[0008] The connecting assembly includes a plurality of pressure-equalizing tubes connected in sequence, a connector for connecting two adjacent pressure-equalizing tubes, and an insulating member wound around the outside of the pressure-equalizing tubes;

[0009] The lead wire between the first high-voltage coil and the second high-voltage coil is arranged inside the voltage equalizing tube.

[0010] In a preferred embodiment of the present invention, the first high-voltage coil and the second high-voltage coil are of a middle-inlet structure, and the number of turns of the first high-voltage coil and the number of turns of the second high-voltage coil are equal.

[0011] In a preferred embodiment of the present invention, the first high-voltage coil includes a first upper coil and a first lower coil, and the second high-voltage coil includes a second upper coil and a second lower coil; the winding directions of the first upper coil and the first lower coil are opposite, and the winding directions of the second upper coil and the second lower coil are opposite, and the winding directions of the first upper coil and the second upper coil are opposite.

[0012] In a preferred embodiment of the present invention, the connecting assembly includes a first pressure-equalizing tube, a second pressure-equalizing tube and a third pressure-equalizing tube connected in sequence, a first connecting piece for connecting the first pressure-equalizing tube and the second pressure-equalizing tube, and a second connecting piece for connecting the second pressure-equalizing tube and the third pressure-equalizing tube.

[0013] In a preferred embodiment of the present invention, the two terminal outlets of the first high-voltage coil are respectively a first upper terminal outlet and a first lower terminal outlet, the lead wire led out of the first upper terminal outlet is a first lead wire, the lead wire led out of the first lower terminal outlet is a second lead wire, the first lead wire is electrically connected to the second lead wire, and is electrically connected to the second high-voltage coil through a third lead wire;

[0014] The first lead passes through the first equalizing tube to reach the interior of the second equalizing tube, and the second lead passes through the third equalizing tube to reach the interior of the second equalizing tube. The second equalizing tube is a three-way tube structure, and the first lead, the second lead and the third lead are respectively located in a pipe inside the second equalizing tube.

[0015] In a preferred embodiment of the present invention, the first connecting member includes an aluminum tube, a contact plate disposed within the aluminum tube, and a screw for connecting the aluminum tube and the contact plate; the inner wall of the aluminum tube is provided with an internal thread, and the contact plate is threadedly connected to the interior of the aluminum tube. The number of the contact plates is at least two and is evenly distributed along the circumference of the aluminum tube;

[0016] One end of the aluminum tube is connected to the first pressure-equalizing tube, and the other end is connected to the second pressure-equalizing tube. The first pressure-equalizing tube and the second pressure-equalizing tube are electrically connected through the contact plate.

[0017] In a preferred embodiment of the present invention, the second connecting member includes a first fixing plate, a second fixing plate, four terminal blocks, a lead connector and an insulated connecting lead; the first fixing plate and the second fixing plate are snap-fitted together, and the cross-sections of the first fixing plate and the second fixing plate perpendicular to the axial direction of the second equalizing pressure tube are arc-shaped. The first fixing plate and the second fixing plate are snap-fitted together to form an accommodating cavity, which is a cylindrical space; when the first fixing plate and the second fixing plate are snap-fitted together, they at least cover part of the second equalizing pressure tube and the third equalizing pressure tube.

[0018] In a preferred embodiment of the present invention, the lead connector is detachable and includes a first portion and a second portion connected by bolts, the first lead and the third lead are electrically connected to the first portion, and the second lead is electrically connected to the second portion.

[0019] In a preferred embodiment of the present invention, the four terminal blocks are respectively a first terminal block, a second terminal block, a third terminal block and a fourth terminal block; the first terminal block is fixed inside the second equalizing voltage tube and electrically connected to the second equalizing voltage tube, the second terminal block is fixed inside the first fixing plate and electrically connected to the first fixing plate, the third terminal block is fixed inside the third equalizing voltage tube and electrically connected to the third equalizing voltage tube, and the fourth terminal block is fixed inside the second fixing plate and electrically connected to the second fixing plate; the second part of the lead connector, the fourth terminal block, the first terminal block, the second terminal block and the third terminal block are electrically connected in sequence through insulated connecting leads.

[0020] In a preferred embodiment of the present invention, it further includes a white cloth tape and crepe paper, wherein the white cloth tape is half-folded and wound on the outside of the first lead, the second lead, the third lead and the lead joint in four layers; the crepe paper is half-folded and wound on the outside of the first equalizing pressure tube, the second equalizing pressure tube, the third equalizing pressure tube, the first connecting piece and the second connecting piece.

[0021] The technical solution provided by the present invention has the following advantages compared with the prior art:

[0022] The present invention adopts a double-column series structure. The number of high-voltage coil turns on the two core columns is equal. The series connection potential between the high-voltage columns is 1 / 2 of the high-voltage head end potential, which reduces the lead potential and easily ensures the electrical insulation strength of the lead. The structure of the equalizing tube plus lead connection has a good electrode shape, a simple structure, convenient operation, and high lead insulation reliability. The transformer of the present invention has a small external size, which solves the problems of limited transportation and transportation weight. The lead connection structure is simple, the operation process is good, and the reliability is high. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, without paying any creative work, they can also obtain drawings of other embodiments based on these drawings.

[0024] FIG1 is a schematic diagram of coil connections of a UHV step-up transformer with coil leads connected in series according to one embodiment of the present invention;

[0025] FIG2 is a schematic diagram of the body and outgoing wires of a UHV step-up transformer with coil leads connected in series according to one embodiment of the present invention;

[0026] FIG3 is a schematic diagram of a connection assembly of a UHV step-up transformer with coil leads connected in series according to one embodiment of the present invention;

[0027] 4 is a schematic diagram of a first connector of an ultra-high voltage step-up transformer with coil leads connected in series according to one embodiment of the present invention;

[0028] FIG5 is a cross-sectional view taken along line AA in FIG4 ;

[0029] FIG6 is a schematic diagram of a second connector of an ultra-high voltage step-up transformer with coil leads connected in series according to an embodiment of the present invention.

[0030] As shown in the figure: 101-first high-voltage coil; 102-second high-voltage coil; 201-first equalizing tube; 202-second equalizing tube; 203-third equalizing tube; 301-first connecting piece; 3011-aluminum tube; 3012-contact plate; 3013-screw; 302-second connecting piece; 3021-first fixing plate; 3022-second fixing plate; 3023-first terminal block; 3024-second terminal block; 3025-third terminal block; 3026-fourth terminal block; 3027-lead connector; 3028-connecting lead; 401-first lead; 402-second lead; 403-third lead. DETAILED DESCRIPTION

[0031] For ease of understanding, the following describes an ultra-high voltage step-up transformer with coil leads connected in series with reference to embodiments. It should be understood that these embodiments are only used to illustrate the present invention and are not used to limit the scope of the present invention.

[0032] In the description of the present invention, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicating orientations or positional relationships, are based on the orientations and positional relationships shown in the accompanying drawings and are intended solely to facilitate and simplify the description of the present invention. They are not intended to indicate or imply that the devices or components referred to must have, be constructed, or operate in a specific orientation, and therefore should not be construed as limitations on the present invention. Furthermore, the terms "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0033] In the description of the present invention, it should be noted that, unless otherwise expressly specified or limited, the terms "mounted," "connected," and "connected" should be understood broadly. For example, they may refer to fixed, detachable, or integral connections; mechanical or electrical connections; direct or indirect connections through an intermediary; and internal communication between two components. Those skilled in the art will understand the specific meanings of the above terms in the present invention.

[0034] To facilitate understanding of the present invention, the present invention will be described more fully below with reference to the accompanying drawings. The accompanying drawings illustrate preferred embodiments of the present invention. However, the present invention may be implemented in many different forms and is not limited to the embodiments described herein. Rather, these embodiments are provided to provide a more thorough and comprehensive understanding of the present disclosure.

[0035] As shown in Figure 1, the present invention discloses an ultra-high voltage step-up transformer with coil leads connected in series, which includes two core legs with coils, a first high-voltage coil 101 wound on one core leg, a second high-voltage coil 102 wound on the other core leg, and a connecting assembly for connecting the first high-voltage coil 101 and the second high-voltage coil 102.

[0036] Both the first high-voltage coil 101 and the second high-voltage coil 102 use central feed lines. The first high-voltage coil 101 and the second high-voltage coil 102 have the same number of turns and are connected in series. Specifically, the first high-voltage coil 101 includes a first upper coil and a first lower coil, and the second high-voltage coil 102 includes a second upper coil and a second lower coil. The first upper coil and the first lower coil have opposite winding directions, while the second upper coil and the second lower coil have opposite winding directions. The first upper coil and the second upper coil have opposite winding directions.

[0037] In conjunction with Figures 1 and 2, the two terminal outlets of the first high-voltage coil 101 are led out at the same interval between phases, as shown in Figure 2, and the angle α between the center of the outlet and the center of the device body is between 40° and 60°. Similarly, the two terminal outlets of the second high-voltage coil 102 are also led out at the same interval between phases, and the angle α between the center of the outlet and the center of the device body is between 40° and 60° to ensure the electrical distance between the lead wires and other components when leading out. The two terminal outlets of the first high-voltage coil 101 are electrically connected to the middle first outlet of the second high-voltage coil 102, and the two terminal outlets of the second high-voltage coil 102 are electrically connected and then connected to external components. In this way, the series connection of the first high-voltage coil 101 and the second high-voltage coil 102 is achieved.

[0038] Combined with Figure 1 and Figure 3, the two end outlets of the first high-voltage coil 101 are respectively the first upper end outlet terminal and the first lower end outlet terminal, the lead wire led out of the first upper end outlet terminal is the first lead wire 401, and the lead wire led out of the first lower end outlet terminal is the second lead wire 402. The first lead wire 401 is electrically connected to the second lead wire 402, and is electrically connected to the second high-voltage coil 102 through the third lead wire 403.

[0039] The connection assembly includes a first pressure-equalizing tube 201, a second pressure-equalizing tube 202, and a third pressure-equalizing tube 203 connected in sequence, a first connector 301 for connecting the first pressure-equalizing tube 201 and the second pressure-equalizing tube 202, and a second connector 302 for connecting the second pressure-equalizing tube 202 and the third pressure-equalizing tube 203. A first lead 401 passes through the first pressure-equalizing tube 201 to reach the interior of the second pressure-equalizing tube 202, and a second lead 402 passes through the third pressure-equalizing tube 203 to reach the interior of the second pressure-equalizing tube 202. The second pressure-equalizing tube 202 has a three-way tube structure, and the first lead 401, the second lead 402, and the third lead 403 are each located in a pipe within the second pressure-equalizing tube 202.

[0040] Referring to Figures 4 and 5, the first connecting member 301 includes an aluminum tube 3011, a contact plate 3012 disposed in the aluminum tube 3011, and a screw 3013 for connecting the aluminum tube 3011 and the contact plate 3012. An internal thread is provided in the aluminum tube 3011, and the contact plate 3012 is threadedly connected to the interior of the aluminum tube 3011. In addition, the number of contact plates 3012 is at least two and is evenly distributed along the circumference of the aluminum tube 3011. In one embodiment of the present invention, the number of contact plates 3012 is 3. In conjunction with Figures 3 to 5, one end of the aluminum tube 3011 is connected to the first equalizing pressure tube 201, and the other end is connected to the second equalizing pressure tube 202. The first equalizing pressure tube 201 and the second equalizing pressure tube 202 are electrically connected through the contact plate 3012.

[0041] As shown in Figure 3, the first equalizing tube 201 and the second equalizing tube 202 are mechanically and electrically connected through the first connecting piece 301. An insulating tape is also wrapped around the outside of the first connecting piece 301 to enhance the connection strength between the first connecting piece 301 and the first equalizing tube 201 and the second equalizing tube 202.

[0042] As shown in Figures 3 and 6 , the second connector 302 includes a first fixing plate 3021, a second fixing plate 3022, four terminal blocks, a lead connector 3027, and an insulated connecting lead 3028. The first fixing plate 3021 and the second fixing plate 3022 are fastened together, and the cross-section of the first fixing plate 3021 and the second fixing plate 3022 perpendicular to the axis of the second equalizing pressure tube 202 is arc-shaped. The first fixing plate 3021 and the second fixing plate 3022 are fastened together to form a accommodating cavity, which is a cylindrical space. When the first fixing plate 3021 and the second fixing plate 3022 are fastened together, they at least partially cover the second equalizing pressure tube 202 and the third equalizing pressure tube 203.

[0043] The lead connector 3027 is detachable. The detachable connector consists of two parts, which are connected by bolts to form a whole. The lead connector 3027 includes a first part and a second part connected by bolts, wherein the first lead 401 and the third lead 403 are electrically connected to the first part, and the second lead 402 is electrically connected to the second part.

[0044] The four terminal blocks are respectively a first terminal block 3023, a second terminal block 3024, a third terminal block 3025, and a fourth terminal block 3026. The first terminal block 3023 is fixed inside the second voltage-equalizing tube 202 and is electrically connected to the second voltage-equalizing tube 202. The second terminal block 3024 is fixed inside the first fixing plate 3021 and is electrically connected to the first fixing plate 3021. The third terminal block 3025 is fixed inside the third voltage-equalizing tube 203 and is electrically connected to the third voltage-equalizing tube 203. The fourth terminal block 3026 is fixed inside the second fixing plate 3022 and is electrically connected to the second fixing plate 3022.

[0045] The second part of the lead connector 3027, the fourth terminal block 3026, the first terminal block 3023, the second terminal block 3024 and the third terminal block 3025 are fixedly electrically connected in sequence through an insulated connecting lead 3028, so as to achieve equipotential electrical connection between the second equalizing tube 202, the second connecting member 302 and the third equalizing tube 203. An insulating member is also provided on the outside of the second connecting member 302 to achieve fixation between the first fixing plate 3021 and the second fixing plate 3022, and to strengthen the connection strength between the second connecting member 302 and the second equalizing tube 202 and the third equalizing tube 203.

[0046] The insulating member of the present invention comprises white cloth tape and crepe paper. Specifically, the white cloth tape is wound in four layers, half-folded, around the outside of the first, second, and third leads, and the lead connector, to insulate the leads from the voltage-equalizing tube. The crepe paper is wound half-folded around the outside of the first, second, and third voltage-equalizing tubes, the first connector, and the second connector, to insulate the leads from the voltage-equalizing tubes and, in turn, the voltage-equalizing tubes from the transformer.

[0047] In summary, the present invention adopts a double-column series structure, the number of turns of the high-voltage coil of each column is half of the total number of turns of the high-voltage coil, the series connection potential between the high-voltage columns is 1 / 2 of the high-voltage head end potential, the lead potential is reduced, and the electrical insulation strength of the lead is easy to ensure. The structure of the equalizing tube plus lead connection is adopted, the electrode shape is good, the structure is simple, the operation is convenient, and the lead insulation reliability is high. The transformer in the present invention has a small external size, which solves the problems of transportation limit and transportation weight limitation. The lead connection structure is simple, the operation process is good, and the reliability is high.

[0048] Finally, it should be noted that the above embodiments are intended only to illustrate the technical solutions of the present invention and are not intended to limit the present invention. Although the present invention has been described in detail with reference to the above embodiments, those skilled in the art will appreciate that the technical solutions described in the above embodiments may be modified or some or all of the technical features thereof may be replaced with equivalents, and that such modifications or replacements do not deviate from the essence of the corresponding technical solutions within the scope of the various embodiments of the present invention.

Claims

1. A UHV step-up transformer with coil leads connected in series, characterized in that: include: Two core columns of coils, a first high-voltage coil wound on one core column, a second high-voltage coil wound on the other core column, and a connecting assembly for connecting the first high-voltage coil and the second high-voltage coil; The first high-voltage coil is connected in series with the second high-voltage coil; The connection assembly includes a plurality of pressure equalizing tubes connected in sequence, a connector for connecting two adjacent pressure equalizing tubes, and an insulating member wound outside the pressure equalizing tube; The lead wire between the first high-voltage coil and the second high-voltage coil is arranged inside the voltage equalizing tube.

2. The UHV step-up transformer with coil leads connected in series according to claim 1, characterized in that: The first high-voltage coil and the second high-voltage coil are of a middle-inlet structure, and the number of turns of the first high-voltage coil and the number of turns of the second high-voltage coil are equal.

3. The UHV step-up transformer with coil leads connected in series according to claim 1, characterized in that: The first high-voltage coil includes a first upper coil and a first lower coil, and the second high-voltage coil includes a second upper coil and a second lower coil; the winding directions of the first upper coil and the first lower coil are opposite, and the winding directions of the second upper coil and the second lower coil are opposite. The winding directions of the first upper coil and the second upper coil are opposite.

4. The UHV step-up transformer with coil leads connected in series according to claim 1, characterized in that: The connecting assembly includes a first pressure-equalizing tube, a second pressure-equalizing tube, and a third pressure-equalizing tube connected in sequence, a first connecting piece for connecting the first pressure-equalizing tube and the second pressure-equalizing tube, and a second connecting piece for connecting the second pressure-equalizing tube and the third pressure-equalizing tube.

5. The UHV step-up transformer with coil leads connected in series according to claim 4, characterized in that: The two terminal outlets of the first high-voltage coil are respectively a first upper terminal outlet and a first lower terminal outlet, the lead wire led out of the first upper terminal outlet is a first lead wire, the lead wire led out of the first lower terminal outlet is a second lead wire, the first lead wire is electrically connected to the second lead wire, and is electrically connected to the second high-voltage coil through a third lead wire; The first lead passes through the first pressure-equalizing tube to reach the interior of the second pressure-equalizing tube, and the second lead passes through the third pressure-equalizing tube to reach the interior of the second pressure-equalizing tube. The second pressure-equalizing tube is a three-way tube structure, and the first lead, the second lead and the third lead are respectively located in a pipeline in the second pressure-equalizing tube.

6. The UHV step-up transformer with coil leads connected in series according to claim 4, characterized in that: The first connecting member includes an aluminum tube, a contact plate arranged in the aluminum tube, and a screw for connecting the aluminum tube and the contact plate; the inner wall of the aluminum tube is provided with an internal thread, the contact plate is threadedly connected to the inside of the aluminum tube, the number of the contact plates is at least two, and they are evenly distributed along the circumference of the aluminum tube; One end of the aluminum tube is connected to the first pressure equalizing tube, and the other end is connected to the second pressure equalizing tube. The first pressure equalizing tube and the second pressure equalizing tube are electrically connected through the contact plate.

7. The UHV step-up transformer with coil leads connected in series according to claim 5, characterized in that: The second connecting member includes a first fixing plate, a second fixing plate, four terminal blocks, a lead connector and an insulated connecting lead; the first fixing plate and the second fixing plate are snap-fitted together, the cross-sections of the first fixing plate and the second fixing plate perpendicular to the axial direction of the second equalizing pressure tube are arc-shaped, the first fixing plate and the second fixing plate are snap-fitted together to form a accommodating cavity, and the accommodating cavity is a cylindrical space; when the first fixing plate and the second fixing plate are snap-fitted together, they at least partially cover the second equalizing pressure tube and the third equalizing pressure tube.

8. The UHV step-up transformer with coil leads connected in series according to claim 7, characterized in that: The lead connector is detachable and includes a first portion and a second portion connected by bolts, the first lead and the third lead are electrically connected to the first portion, and the second lead is electrically connected to the second portion.

9. The UHV step-up transformer with coil leads connected in series according to claim 8, characterized in that: The four terminal blocks are respectively a first terminal block, a second terminal block, a third terminal block and a fourth terminal block; the first terminal block is fixed inside the second voltage-equalizing tube and is electrically connected to the second voltage-equalizing tube, the second terminal block is fixed inside the first fixing plate and is electrically connected to the first fixing plate, the third terminal block is fixed inside the third voltage-equalizing tube and is electrically connected to the third voltage-equalizing tube, and the fourth terminal block is fixed inside the second fixing plate and is electrically connected to the second fixing plate; the second part of the lead connector, the fourth terminal block, the first terminal block, the second terminal block and the third terminal block are electrically connected in sequence through an insulated connecting lead.

10. The UHV step-up transformer with coil leads connected in series according to claim 1, characterized in that: It also includes a white cloth tape and crepe paper, wherein the white cloth tape is half-folded and wound in 4 layers on the outside of the first lead, the second lead, the third lead and the lead joint; the crepe paper is half-folded and wound on the outside of the first equalizing pressure tube, the second equalizing pressure tube, the third equalizing pressure tube, the first connecting piece and the second connecting piece.

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