WO2023056657A1

WO2023056657A1 - High-impedance transformer having built-in reactor

Info

Publication number: WO2023056657A1
Application number: PCT/CN2021/123549
Authority: WO
Inventors: 安振; 高辉; 王炳光; 刘欢; 李国旗
Original assignee: 吴江变压器有限公司
Priority date: 2021-10-10
Filing date: 2021-10-13
Publication date: 2023-04-13
Also published as: CN113903575B; CN113903575A

Abstract

Disclosed is a high-impedance transformer having a built-in reactor, said transformer comprising: three coil assemblies that are arranged as the vertices of a regular triangle according to the center point, and a fixing assembly used for connecting the coil assemblies. The fixing assembly comprises an upper pressing plate located above the coil assemblies, an upper clamping piece located on the upper pressing plate, a lower supporting plate located below the coil assemblies, a lower clamping piece located below the lower supporting plate, and three rod-like tensioning mechanisms that pass through the coil assemblies; one end of each rod-like tensioning mechanism is fixedly connected to the upper clamping piece by means of the upper pressing plate, and the other end passes through the lower supporting plate to be fixedly connected to the lower clamping piece. According to the present invention, a built-in series reactor is used, and the device body is arranged in a "品" shape, thus the weight is obviously reduced, the production efficiency is high, costs are low, and performance is reliable. Moreover, processing is simple, product noise is reduced, the size and weight are small, and movement and mounting are convenient. In addition, by using a "品" shape, three-phase magnetic flux leakage can be ensured to be mutually balanced, thus preventing overheating and reducing loss, while potential safety hazards can be reduced.

Description

A High Impedance Transformer with Built-in Reactor

Application field

The invention relates to the field of transformers and reactors, in particular to a high-impedance transformer with built-in reactors.

Background technique

To achieve safe operation of the power grid, it is necessary to improve the short-circuit resistance of the transformer, reduce the change rate of the grid voltage and the short-circuit current value, and these two parameters are determined by the short-circuit impedance value of the transformer, that is, to reduce the grid voltage The rate of change and short-circuit current value, it is necessary to increase the impedance value of the transformer. For transformers, series reactors are usually used to replace most of the equipment impedance on the low-voltage coil of the transformer to achieve high-impedance operation. Generally speaking, for the convenience of reactor installation, the three coils of the reactor are arranged in a straight line.

However, since the series reactor and the main body of the transformer share the same oil tank, when the reactor coils are arranged in a straight line, it will take up more space, that is, the oil tank needs to be expanded, and its footprint is larger. Production and transportation The cost is higher. Moreover, when the three coils of the reactor are arranged in a straight line, the three-phase magnetic flux leakage cannot be balanced, which will cause large loss of structural parts, heat generation of structural parts, and harmful gas will be generated at the same time.

Contents of the invention

The present invention overcomes the disadvantages in the prior art that when the three coils of the reactor are arranged in a straight line, it takes up a large space and the three-phase flux leakage cannot be balanced, and provides a high-impedance transformer with a built-in reactor. In order to achieve the above-mentioned purpose, the present invention The technical solution adopted in the invention is: a high-impedance transformer with a built-in reactor, which includes: a low-voltage side coil, a high-voltage side coil, and a reactor correspondingly connected to the low-voltage side coil, characterized in that the reactor includes, Three coil components arranged in such a way that the center points are located at vertices of an equilateral triangle and a fixed component for connecting the coil components;

The fixing assembly includes an upper pressing plate located above the coil assembly, an upper clamping piece located on the upper pressing plate, a lower supporting plate located below the coil assembly, a lower clamping element located under the lower supporting plate and a through-hole Through the three rod-shaped tensioning mechanisms of the coil assembly, one end of the rod-shaped tensioning mechanism passes through the upper pressing plate and is fixedly connected with the upper clip, and the other end passes through the lower supporting plate and the lower clamping member. The clips are fixedly connected.

In a preferred embodiment of the present invention, the fixing assembly further includes an upper magnetic shield plate and a lower magnetic shield plate, the upper magnetic shield plate is arranged between the upper pressing plate and the upper clamping piece, and the lower magnetic shield plate The screen plate is arranged between the lower support plate and the lower clamping piece.

In a preferred embodiment of the present invention, the upper magnetic shield plate is composed of a silicon steel strip and an insulating layer arranged on the surface of the silicon steel strip, and the lower magnetic shield plate is composed of a silicon steel strip and an insulating layer arranged on the surface of the silicon steel strip. Silicon steel with ground lug for electrical connection to ground.

In a preferred embodiment of the present invention, the coil assembly includes a support cylinder sleeved on the corresponding rod-shaped tensioning mechanism and a coil wound on the outer surface of the support cylinder, and the support cylinder is wound around a wooden skeleton Insulation mechanism composed of cardboard.

In a preferred embodiment of the present invention, a rod-shaped tensioning mechanism is also arranged in the area surrounded by the three coil components.

In a preferred embodiment of the present invention, the upper pressing plate is a circular plate covering all the coil components, the upper clamping piece is concentric with the upper pressing plate, and three brackets extend from the central position to the direction of the three rod-shaped tensioning mechanisms The arm has a trident structure as a whole;

The lower supporting plate is a circular plate covering the bottom of all coil components, the lower clamping piece is concentric with the lower supporting plate, and three support arms extend from the center to the direction of the three rod-shaped tensioning mechanisms, and the whole is trident structure.

In a preferred embodiment of the present invention, the fixing assembly further includes several insulating pads arranged at the bottom of the lower splint.

In a preferred embodiment of the present invention, the reactor is located at one end of the three-phase in-line transformer, and the coils correspond to the coils of the three phases inside the transformer, specifically A-phase coil, B-phase coil and The C-phase coil, the connecting lead wire drawn from the coil is connected to the low-voltage coil of the corresponding phase in the transformer through the lug and the copper bar in turn, and the three coils are arranged in the XYZ three-dimensional space.

In a preferred embodiment of the present invention, in the XYZ three-dimensional space, the three-phase low-voltage coil of the transformer is connected to the reactor from the X-directed copper bar, the A-phase coil is close to the transformer, and the connecting lead of the A-phase coil is in the X-direction, Connect the Y-direction copper bar through the lug, the connection lead wire of the B-phase coil is in the Y direction, and connect the X-direction to Y-direction copper bar through the lug, the connection lead wire of the C-phase coil is Z direction, and the connection lead wire of the C-phase coil is in the Z direction. Connect the X direction to the Z direction copper bar first.

In a preferred embodiment of the present invention, the rod-shaped tensioning mechanism is composed of several rod-shaped tensioning mechanisms, and the rod-shaped tensioning mechanisms are evenly distributed on the circumference of the same circle, and the center of the circle is the rod-shaped tensioning mechanism. The center of the coil assembly corresponding to the shape tensioning mechanism.

The present invention solves the defect existing in the background technology, and the present invention has the following beneficial effects:

(1) The present invention adopts a built-in series reactor, and the body is arranged in the shape of "product", which significantly reduces the weight, high production efficiency, low cost, and reliable performance; and the processing is simple, the product noise is reduced, the volume and quality are small, and it is easy to move and install. In addition, adopting the setting of "pin" can ensure that the three-phase magnetic flux leakage is balanced with each other, avoiding overheating, reducing loss, and reducing potential safety hazards.

(2) The structural shape of the upper clamp and the lower clamp is trident, which has the technical characteristics of force balance, high material utilization rate, and low structural loss, and the materials of the upper clamp and the lower clamp are metal parts, which strengthen In order to improve the mechanical strength, the rod-shaped tensioning mechanism is fixedly connected with the upper clamp or the lower clamp, and its fixing strength is stronger.

(3) The present invention has the advantages of simple structure, high production efficiency, small footprint and low cost, and is suitable for environments with strict requirements on space size.

Description of drawings

In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings that need to be used in the description of the embodiments or the prior art. Obviously, the accompanying drawings in the following description are only These are some embodiments of the present invention. Those skilled in the art can also obtain the drawings of other embodiments according to these drawings without creative work.

Fig. 1 is a front view of a high-impedance transformer with a built-in reactor described in an embodiment of the present invention;

Fig. 2 is a top view of a high-impedance transformer with a built-in reactor described in an embodiment of the present invention;

Fig. 3 is a schematic diagram of the connection between the coil of the reactor and the coil of the transformer according to an embodiment of the present invention.

Reference signs are as follows: 01, high-voltage coil; 02, low-voltage coil; 10, coil assembly; 101, support cylinder; 102, coil; 1021, lead wire; 103, copper sheet; 20, fixed component; , upper clamping piece; 203, upper magnetic screen plate; 204, rod-shaped tensioning mechanism; 2041, screw rod; 205, lower supporting plate; 206, lower clamping piece; 207, lower magnetic screen plate; Locator; 401, lug piece; 402, copper bar; 403, wood piece; 404, detachable soft wiring piece.

Detailed ways

In order to more clearly understand the above objects, features and advantages of the present invention, the present invention will be further described in detail below in conjunction with the accompanying drawings and specific embodiments. structure, so it only shows the configuration related to the present invention, and it should be noted that, in the case of no conflict, the embodiments in the present application and the features in the embodiments can be combined with each other.

In the description of the present application, it should be understood that the terms "center", "longitudinal", "transverse", "upper", "lower", "front", "rear", "left", "right", " The orientation or positional relationship indicated by "vertical", "horizontal", "top", "bottom", "inner", "outer", etc. is based on the orientation or positional relationship shown in the drawings, and is only for the convenience of describing the present application and Simplified descriptions do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operate in a specific orientation, and thus should not be construed as limiting the scope of protection of the present application. In addition, the terms "first", "second", etc. are used for descriptive purposes only, and cannot be interpreted as indicating or implying relative importance or implicitly specifying the quantity of the indicated technical features. Thus, a feature defined as "first", "second", etc. may expressly or implicitly include one or more of that feature. In the description of the present invention, unless otherwise specified, "plurality" means two or more.

In the description of this application, it should be noted that unless otherwise specified and limited, the terms "installation", "connection", and "connection" should be understood in a broad sense, for example, it can be a fixed connection or a detachable connection. Connected, or integrally connected; it can be mechanically connected or electrically connected; it can be directly connected or indirectly connected through an intermediary, and it can be the internal communication of two components. Those of ordinary skill in the art can understand the specific meanings of the above terms in this application based on specific situations.

In order to facilitate the understanding of the present invention, the present invention will be described more fully below with reference to the associated drawings. Preferred embodiments of the invention are shown in the accompanying drawings. However, the present invention can be embodied in many different forms and is not limited to the embodiments described herein. On the contrary, the purpose of providing these embodiments is to make the disclosure of the present invention more thorough and comprehensive.

Referring to FIG. 3 , a high-impedance transformer with a built-in reactor, a low-voltage side coil 02, a high-voltage side coil 01, and a reactor correspondingly connected to the low-voltage side coil, wherein, referring to FIG. 1 , the reactor includes: Three coil components 10 arranged in such a way that the center points are located at vertices of an equilateral triangle and a fixing component 20 for connecting the coil components 10 are provided.

That is to say, in the high-impedance transformer with built-in reactor described in the present invention, the three internal coils 102 are arranged in the shape of "pin", and the three-phase magnetic flux leakage is balanced with each other, so that other safety hazards will not be caused by local overheating inside. Hidden danger. And this kind of arrangement is more compact than the "one" arrangement, that is, it occupies a smaller volume and does not need to expand the oil tank of the transformer.

1-2, the fixing assembly 20 includes an upper plate 201 located on the coil assembly 10, an upper clamp 202 located on the upper plate 201, and an upper magnetic shield arranged between the upper plate 201 and the upper clamp 202. Plate 203, the lower support plate 205 located under the coil assembly 10, the lower clamp 206 located under the lower support plate 205, the lower magnetic shield plate 207 arranged between the lower support plate 205 and the lower clamp 206 and the coil passing through The three rod-shaped tensioning mechanisms 204 of the assembly 10, one end of the rod-shaped tensioning mechanism 204 passes through the upper platen 201 and the upper magnetic shield plate 203 in sequence, and finally is fixedly connected with the upper clamp 202, and the other end passes through the lower supporting plate 205 in sequence and the lower magnetic shield plate 207, and finally fixedly connected with the lower clip 206.

It is not difficult to see that the fixing assembly 20 is provided with a plate-shaped fixing member for fixing and clamping the coil 102 at the upper end and the lower end of the coil 102, and is fixed with a rod-shaped tensioning mechanism 204 in the middle to connect it as a complete whole . The upper magnetic shield plate 203 and the lower magnetic shield plate 207 are provided for magnetic shielding, which reduces the leakage flux and prevents the magnetic field lines generated after the coil 102 is energized from entering the oil tank of the transformer, causing overheating of the oil tank of the transformer.

Specifically, the upper magnetic shield plate 203 is composed of a silicon steel strip and an insulating layer arranged on the surface of the silicon steel strip, the lower magnetic shield plate 207 is composed of a silicon steel strip and an insulating layer arranged on the surface of the silicon steel strip, and the silicon steel strip is electrically connected to the grounding sheet . Silicon steel material has high magnetic permeability and good magnetic shielding effect. The present invention uses the upper magnetic shield plate 203 and the lower magnetic shield plate 207 to replace the iron core or the upper and lower iron yokes of the traditional inline reactor. required environment.

Continuing to refer to FIGS. 1-2, the coil assembly 10 includes a support cylinder 101 sleeved on the corresponding rod-shaped tensioning mechanism 204 and a coil 102 wound on the outer surface of the support cylinder 101. The apexes of the triangles are arranged in a way, and the support cylinder 101 is an insulating mechanism composed of cardboard wrapped around a wooden skeleton.

A rod-shaped tensioning mechanism 204 is also provided in the area surrounded by the three coil assemblies 10 . The rod-shaped tensioning mechanism 204 is composed of several screw rods 2041 , and the screw rods 2041 are evenly distributed on the circumference of the same circle, and the center of the circle is the center of the coil assembly 10 corresponding to the rod-shaped tensioning mechanism 204 .

Here, according to the magnetic flux characteristics, the screw rod 2041 in the rod-shaped tensioning mechanism 204 can be conductive or non-conductive. According to the distribution of the magnetic force lines, the connection mode of the upper and lower metal parts is determined to form a reasonable magnetic circuit and grounding. system to avoid commutation and overheating.

Referring to Fig. 2, the upper pressing plate 201 is a circular plate covering all the coil assemblies 10, the upper clamping piece 202 is concentric with the upper pressing plate 201, and three support arms extend from the central position to the direction of the three rod-shaped tensioning mechanisms 204, The whole is a trident structure; the lower supporting plate 205 is a circular plate covering the bottom of all coil assemblies 10, the lower clamping piece 206 is concentric with the lower supporting plate 205, and three rod-shaped tensioning mechanisms 204 extend from the central position to the three rod-shaped tensioning mechanisms 204. The bracket arm has a trident structure as a whole. The structural profile of the upper clamping part 202 and the lower clamping part 206 is a trident shape, which has the technical characteristics of balanced force, high material utilization rate, and low structural loss. Moreover, here, the materials of the upper clamping part 202 and the lower clamping part 206 are metal parts, which enhances the mechanical strength, and the rod-shaped tensioning mechanism 204 is fixedly connected with the upper clamping part 202 and the lower clamping part 206, and its fixing strength is stronger.

Referring to FIG. 1 , the fixing assembly 20 further includes several insulating spacers 301 arranged at the bottom of the lower splint. The insulating spacer 301 here is made of flexible material, which slows down the vibration of the transformer body and reduces the working noise caused by the body and the ground when the transformer is in operation, and the bottom of the fixing assembly 20 is also provided with a locator 302, which can It helps the three coils 102 of the reactor to be assembled more precisely, which ensures that the three flux leakages can be balanced with each other.

Referring to Figure 3, the reactor is located at one end of the three-phase in-line transformer, and the coils 102 correspond to the three-phase coils 102 inside the transformer, specifically, the A-phase coil 102, the B-phase coil 102 and the C-phase coil 102, the connecting lead wire 1021 drawn from the coil 102 is connected to the low-voltage coil 102 of the corresponding phase in the transformer through the lug 401 and the copper bar 402 in turn, and the three coils 102 are arranged in the XYZ three-dimensional space. Specifically, in the XYZ three-dimensional space, the transformer three-phase low-voltage coil 102 is connected to the reactor from the X-directed copper bar 402, the A-phase coil 102 is close to the transformer, and the connecting lead wire 1021 of the A-phase coil 102 is in the X-direction. The piece 401 is connected to the Y-direction copper bar 402, the connection lead wire 1021 of the B-phase coil 102 is in the Y direction, and the X-direction is connected to the Y-direction copper bar 402 through the lug 401, and the connection lead wire 1021 of the C-phase coil 102 is in the Z direction. The lug 401 is connected to the copper bar 402 that turns from the X direction to the Z direction.

Here, the copper bar 402 is fixed by a wooden piece 403 . Moreover, the reactor and the transformer are flexibly connected through a detachable flexible wire piece 404 . The detachable connection is adopted here, and it is more convenient to disassemble the body of the reactor and the body of the transformer, and it is also convenient for transportation.

In addition, due to the magnetic shielding of the reactor and other metal structural parts, under the action of the electric field of the coil 102, they have different potentials, which are different from the potential of the fuel tank. Although the potential difference between them is not large, they will continue to discharge through a small insulation distance. On the one hand, the discharge causes the oil to decompose, and on the other hand, it is impossible to confirm whether the transformer is in a normal state during the test and operation, so the iron core and its metal structural parts must be grounded. The upper magnetic shield plate 203 in the present invention is connected with the upper clamp 202 through the copper sheet 103, the lower magnetic shield plate 207 is connected with the lower clamp 206 through the copper sheet 103, and the upper clamp 202 and the lower clamp 206 are connected by the low magnetic steel Rod tensioning mechanisms 204 are connected together. The reactor as a whole falls on the bottom of the transformer oil tank through the shock-absorbing structure, and finally connects with the main body of the transformer through the connection lead 1021 to ensure a little grounding, which also ensures the normal operation of the transformer and the reactor.

Compared with the body structure of the built-in series reactor, the volume and weight of the reactor structure provided by the invention are obviously reduced, and the production efficiency is high, the cost is low, and the performance is reliable. Moreover, the processing is simple, the noise of the product is reduced, the volume and quality are small, and it is easy to move and install. Moreover, adopting the setting of the character "pin" can ensure the mutual balance of the three-phase magnetic flux leakage, avoid overheating, reduce loss, and reduce potential safety hazards.

The above examples only express several implementation modes of the present invention, and the description thereof is relatively specific and detailed, but should not be construed as limiting the patent scope of the invention. It should be noted that those skilled in the art can make several modifications and improvements without departing from the concept of the present invention, and these all belong to the protection scope of the present invention. Therefore, the protection scope of the patent for the present invention should be based on the appended claims.

Claims

A high-impedance transformer with a built-in reactor, which includes: a low-voltage side coil, a high-voltage side coil, and a reactor correspondingly connected to the low-voltage side coil, wherein the reactor includes three Coil components arranged in the form of triangular vertices and a fixing component for connecting the coil components;

The fixing assembly includes an upper pressing plate located above the coil assembly, an upper clamping piece located on the upper pressing plate, a lower supporting plate located below the coil assembly, a lower clamping element located under the lower supporting plate and a through-hole Through the three rod-shaped tensioning mechanisms of the coil assembly, one end of the rod-shaped tensioning mechanism passes through the upper pressing plate and is fixedly connected with the upper clip, and the other end passes through the lower supporting plate and the lower clamping member. The clips are fixedly connected.
The high-impedance transformer with built-in reactor according to claim 1, characterized in that: the fixing assembly further includes an upper magnetic shield plate and a lower magnetic shield plate, and the upper magnetic shield plate is arranged between the upper pressure plate and the lower magnetic shield plate Between the upper clips, the lower magnetic shield is arranged between the lower supporting plate and the lower clips.
A high-impedance transformer with built-in reactor according to claim 2, characterized in that: the upper magnetic shield plate is composed of a silicon steel strip and an insulating layer arranged on the surface of the silicon steel strip, and the lower magnetic shield plate is composed of a silicon steel strip and an insulating layer arranged on the surface of the silicon steel strip, the silicon steel strip is electrically connected to the grounding sheet.
The high-impedance transformer with built-in reactor according to claim 1, characterized in that: the coil assembly includes a support cylinder sleeved on the corresponding rod-shaped tensioning mechanism and a coil wound around the outer surface of the support cylinder. coil, and the supporting cylinder is an insulating mechanism composed of wooden skeleton wound with cardboard.
The high-impedance transformer with built-in reactor according to claim 1, characterized in that: a rod-shaped tensioning mechanism is also arranged in the area surrounded by the three coil assemblies.
A high-impedance transformer with built-in reactor according to claim 1, characterized in that: the upper pressing plate is a circular plate covering all the coil components, the upper clamping piece is concentric with the upper pressing plate, three directions from the center position Three bracket arms are extended in the direction of a rod-shaped tensioning mechanism, and the whole is a trident structure;

The lower supporting plate is a circular plate covering the bottom of all coil components, the lower clamping piece is concentric with the lower supporting plate, and three support arms extend from the center to the direction of the three rod-shaped tensioning mechanisms, and the whole is trident structure.
The high-impedance transformer with built-in reactor according to claim 1, characterized in that: the fixing assembly further includes several insulating pads arranged at the bottom of the lower splint.
A high-impedance transformer with built-in reactor according to claim 1, characterized in that: the reactor is located at one end of the three-phase in-line transformer, and the coil is one-to-one with the three-phase coils inside the transformer Corresponding, specifically A-phase coils, B-phase coils and C-phase coils, the connecting leads drawn from the coils are connected to the low-voltage coils of the corresponding phases in the transformer through lugs and copper bars in turn, and the three coils pass through the XYZ three-dimensional space arranged.
The high-impedance transformer with built-in reactor according to claim 8, characterized in that: in the XYZ three-dimensional space, the three-phase low-voltage coil of the transformer is connected to the reactor from the copper bar running in the X direction, and the A-phase coil is close to Transformer, the connecting lead wire of the A-phase coil is in the X direction, and is connected to the Y-direction copper bar through the lug, the connecting lead wire of the B-phase coil is in the Y direction, and is connected to the X-direction to Y-direction copper bar through the lug, and the C The connection leads of the phase coils are in the Z direction, and are connected to the X direction to the Z direction copper bar through the lug.
The high-impedance transformer with built-in reactor according to claim 1, characterized in that, the rod-shaped tensioning mechanism is composed of several rod-shaped tensioning mechanisms, and the rod-shaped tensioning mechanisms are evenly distributed in the same circle On the circumference, the center of the circle is the center of the coil assembly corresponding to the rod-shaped tensioning mechanism.