JP2018182200A - Coil - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a coil that can be made by equipment without relying on skilled workers.SOLUTION: The coil includes: a conductor 1a made of a conductive part of aluminum or an aluminum alloy extending spirally along the same plane; a penetrating groove 3 extending spirally between the conductive wires and penetrating continuously through the front and rear surfaces of the conductor 1a; and a resin 2 filled in the penetrating groove 3.SELECTED DRAWING: Figure 2

Description

  Embodiments of the present invention relate to a coil.

  In recent years, gas insulated switchgear has come to be used in a wide range from an underground substation in an urban area to an outdoor substation. A gas insulated current transformer is installed as one of the components of the gas insulated switchgear. The gas-insulated current transformer accommodates the wound copper wire in the metal shield case for electric field relaxation as a primary conductor, and also accommodates the current transformer wound around the outer periphery of the annular core as a secondary conductor. Crosses the primary conductor and the secondary conductor. Since high mechanical strength can not be obtained with a copper wire itself, by fixing in a metal shield case via an insulator such as resin or PET, the strength against electromagnetic mechanical force is improved. Such a gas-insulated current transformer is housed in a pressure vessel. Both ends of the primary conductor are connected to the high voltage charger through the insulating spacer, and the current flowing through the secondary conductor is output to the outside of the pressure vessel through the low voltage terminal plate.

  In the conventional gas-insulated current transformer, the high voltage applied to the high-pressure charging unit is drawn into the pressure vessel with a copper wire, and the connected copper wire is wound a plurality of times to form a primary conductor. Since a large current flows through the primary conductor, the primary conductor is shaped by a winding form and finished by hand while precisely insulating a copper wire having a large current-carrying capacity, generally a flat copper wire having a large cross-sectional area.

Japanese Utility Model Application Publication No. 4-127632 Japanese Utility Model Application Publication 63-119221

  Since the number of turns of the primary conductor of the gas-insulated current transformation device described above is aligned along the axis of the primary conductor and becomes solid on a cylinder, it has been necessary to spirally wind copper wires with high density with high accuracy. For this purpose, it is necessary to form the copper wires in a winding fashion while insulating the individual copper wires so that adjacent copper wires do not come in contact with each other. Furthermore, in order to improve the magnetoresistance mechanical force, it is also necessary to fix it to a metal case using a hardening tape. These operations required high-level manual work and machining time, and they had to rely on skilled workers.

  The problem to be solved by the invention is to provide a coil which can be produced by the device without resorting to skilled workers.

  The coil according to the present embodiment spirally extends between the conductive portion and a conductor made of a conductive portion of aluminum or aluminum alloy spirally extending along the same plane, and continuously penetrates the front and back of the conductor. A through groove and a resin filled in the through groove are provided.

It is a figure which shows the schematic structure of the gas insulated current transformer which concerns on 1st Embodiment. It is a front view which shows the structure of the primary conductor for gas insulated current transformers which concerns on 1st Embodiment. It is a top view which shows the structure of the gas insulated current transformer primary conductor which concerns on 1st Embodiment. It is an AA 'cross section showing the structure of the primary conductor for gas insulated current transformers concerning a 1st embodiment. It is an AA 'cross section which shows the structure of two conductors of the primary conductor for gas insulated current transformers concerning 1st Embodiment. It is a top view which shows the structure of two conductors of the primary conductor for gas insulated current transformers concerning 1st Embodiment. It is a fragmentary sectional view which shows the structure which filled resin with two conductors of the primary conductor for gas insulated current transformers concerning a 1st embodiment. As a first modification of the primary conductor for gas-insulated current transformer according to the first embodiment, a structure in which three turns are formed on the conductor to form a six-turn primary conductor for gas-insulated current transformer with two conductors It is a front view of. It is a fragmentary sectional view showing the 2nd modification of the primary conductor for gas insulated current transformers concerning a 1st embodiment. It is a fragmentary sectional view showing the 3rd modification of a gas insulated current transformer primary conductor concerning a 1st embodiment. It is a fragmentary sectional view which shows the structure of the gas insulated current transformer primary conductor which concerns on 2nd Embodiment. It is the front view which shows the structure of the primary conductor for gas insulated current transformers which concerns on 2nd Embodiment, and BBA cross-sectional view.

First Embodiment
(1-1. Configuration)
A gas insulated current transformer primary conductor 10 according to a first embodiment will be described in detail with reference to the drawings. FIG. 1 is a view showing a schematic configuration of a gas-insulated current transformer 20 according to a first embodiment. The gas-insulated current transformer 20 is used as an example of a switch that constitutes a gas-insulated switchgear. The gas-insulated current transformer 20 comprises a pressure vessel 16, in which the primary conductor 10 and the secondary conductor 14 are accommodated. The primary conductor 10 and the secondary conductor 14 are both so-called coils, and are arranged to cross in a chain.

  The primary conductor 10 is further accommodated in a metal shield case 12. A lead wire 11 is connected to the primary conductor 10, and the lead wire 11 is drawn out from the metal shield case 12 and connected to the high voltage charging portion 19 of the gas insulated current transformer 20. The high voltage charging unit 19 is supported in the pressure vessel 16 via the insulating spacer 17. The gas-insulated current transformer 20 has a low voltage terminal plate 18 attached to the pressure vessel 16, and the secondary conductor 14 is electrically connected to the low voltage terminal plate 18, and a secondary current is externally provided to the pressure vessel 16. Output.

  As shown in FIGS. 2, 3 and 4, the primary conductor 10 comprises a conductor 1a. The conductor 1a has the whole shape of the half-piece part which cut | disconnected the doughnut-shaped torus body along a large radius. The conductor 1a has the shape of a half body section in which the torus body is cut along a plane including the great circle. A torus body is a continuum of small circles formed by continuously connecting small circles having a small radius based on a large circle having a large radius. The plane including the small circle is orthogonal to the plane including the great circle, and the plane including the small circle passes through the center of the great circle. The center of the small circle coincides with the circumference of the great circle. The small circles are continuously connected along the circumference of the great circle. One surface of the conductor 1a bulges in a substantially semicircular shape, and the surface of the conductor 1a opposite to the bulge side is flat. Specifically, the conductor 1a is not a complete torus body, but the top portion of the semicircular bulging surface is scraped off flat, and the inner and outer peripheral surfaces of the great circle are scraped off, but the primary The profile of the cross section may be circular so that the electric field is not concentrated as a whole of the conductor 10, and the conductor 1a may be formed such that the corners and corners of the ring shaped body having a rectangular cross section are scraped off. .

  In the conductor 1a, conductive portions are arranged in the radial direction of a large circle with a gap. The conductor 1a forms a ring portion by spirally swirling one conductive portion along the same plane. The direction of the spiral may be counterclockwise or clockwise. For example, the conductor 1a has six turns in the radial direction of the conductor 1a. The conductor 1a is made of, for example, aluminum or an aluminum alloy. However, the type of aluminum can be selected based on the environment in which the conductor 1a is used, the strength against electromagnetic mechanical force, the cross-sectional area, the conductivity or the thermal conductivity, and so-called 6000 in which magnesium and silicon are added, for example. A series of aluminum alloys can be used.

  The primary conductor 10 further includes a through groove 3 and a resin 2. There is a gap of 2 mm to 10 mm between the conductive portion and the conductive portion of the conductor 1a, and the through groove 3 is this gap. That is, the through groove 3 spirally extends between the conductive portions and the conductive portion, and continuously penetrates the front and back of the conductor 1a. The resin 2 is filled in the through groove 3 and binds between the conductive parts adjacent in the radial direction to maintain the shape of the conductor 1a on the same plane. The resin 2 is not exposed to the substantially semicircular one surface of the primary conductor 10, but is filled only in the region 5 mm or more inside from the surface of the substantially semicircular surface. The resin 2 may be a natural resin or a synthetic resin. In the case of a natural resin, it may be of plant origin or of animal origin. Furthermore, the resin 2 may be an adhesive. The resin 2 may be filled all around the through groove 3 but may be partially filled in the circumferential direction of the through groove 3. For example, the resin 2 may be filled in the circumferential direction of the through groove 3 with a width of about 5 cm, and a gap may be provided between the resin 2 and the resin 2. In this case, when the through groove 3 is desired in the circumferential direction, the resin 2, the void, the resin 2, the void..., The resin 2 and the void are alternately arranged. Alternatively, the resin 2 may draw eight lines radially starting from the center of the through groove 3 arranged in a spiral, and the through groove 3 may be filled with the resin with a width of 5 cm around the radial line.

  The conductor 1a is provided with a terminal connection portion 4a, a protrusion 5a, and a connection surface 6. The terminal connection portion 4a is provided at the radially outward end of the conductor 1a formed of a spiral conductive portion, that is, at the outer circumferential end. The terminal connection portion 4a protrudes outward in the radial direction of the conductor 1a. The protrusions 5a are arranged in the circumferential direction in the vicinity of the conductor connection portion 4a on the outermost periphery of the conductor 1a. However, the terminal connection portion 4 a and the protrusion 5 a are line symmetrical with an imaginary line passing through the connection surface 6 and the center of the conductor 1 a. The position where the terminal connection portion 4a and the connection surface 6 are provided is not limited to the end, and may be, for example, near the end, as long as it is provided at least on the conductor 1a.

  The connection surface 6 is provided at the radial center end of the conductor 1, that is, at the central end, extends equidistant between the terminal connection portion 4a and the protrusion 5a, and is positioned on an imaginary line passing through the center of the conductor 1a. Do. The connection surface 6 has a flat surface orthogonal to the axis of the conductor 1a. The conductive portion on the innermost periphery forming the conductor 1a is as wide as the connecting surface 6 in the large radius direction, and the connecting surface 6 is the conductive portion on the innermost periphery forming the conductor 1a It is coplanar.

  As shown in FIGS. 5, 6 and 7, the gas-insulated current transformer primary conductor 10 includes two conductors 1a of the same diameter. The two conductors 1a are coaxially disposed such that the winding directions of the spiral conductive parts are the same, the flat surfaces are parallel to each other, and the flat surfaces are opposite to each other with a predetermined space therebetween. The gap between the conductors 1a is, for example, about 2 [mm] to 6 [mm].

  In this primary conductor 10, the terminal connection portion 4a of one conductor 1a and the projection 5a of the other conductor 1a overlap, and the projection 5a of one conductor 1a and the terminal connection portion 4a of the other conductor 1a overlap. Thus, when the primary conductor 10 composed of the two conductors 1a is axially cut, a large step can not be formed on the entire outline. That is, it is desirable that the terminal connection portion 4a and the protrusion 5a be formed to have the same shape and the same size.

  The connection surfaces 6 of the two conductors 1a also extend equidistantly between the terminal connection 4a and the projection 5a and face each other because they are located on an imaginary line passing through the center of the conductor 1a. The connection surface 6 of the two conductors 1a is electrically connected by being fastened or welded via a conductor such as a bolt, and the two conductors 1a are connected in series. The resin 2 is filled in the gap between the two conductors 1a, and the positional relationship between the two conductors 1a is fixed.

  In the primary conductor 10, the conductor connection portion 4a of one of the conductors 1a serves as an input / output terminal to which the primary current is input and output. Similarly, the conductor connection portion 4a of the other conductor 1a also serves as an output terminal for outputting a primary current. The AC primary current applied to the primary conductor 10 flows through the spiral conductive portion between the conductor connection portion 4a of one of the conductors 1a and the other conductor connection portion 4a.

(1-2. Action and effect)
The operation of the gas insulated current transformer primary conductor 10 of the first embodiment will be described. The gas insulated current transformer primary conductor 10 according to the first embodiment extends in a spiral shape between conductive portions and a conductor 1a made of aluminum or an aluminum alloy provided with a spiral conductive portion along the same plane, and the conductor The through groove 3 continuously penetrates the front and back of 1 a and the resin 2 filled in the through groove 3 are provided.

  That is, the conductor 1a has a shape in which one conductive portion extends spirally from the center side to the outer peripheral side along the same plane. The conductor 1a can be formed by digging by inputting three-dimensional information (spiral information) into a 3D (three dimension) processing machine or the like. The three-dimensional information is the planar position and depth of the through groove 3 and is much simpler than the three-dimensional information of the spirally drawn winding. Therefore, even if it is a 3D processing machine, the conductor 1a can be formed with high accuracy. Further, since the conductive portions are spread in the same plane, the conductor 1a can be formed by melting the material of the conductor 1a and pouring it into a casting. Aluminum or an aluminum alloy has the advantages of being easier to dig, lighter and cheaper than processing copper.

  Therefore, it is possible to cope with mass production, short delivery time, etc. while suppressing variations in finished dimensions and quality, and it is possible to provide a primary conductor 10 for a gas-insulated current transformer independent of skilled workers. Thus, by using aluminum or an aluminum alloy as the conductor 1a, the insulation work and winding work of a rectangular copper wire etc. can be avoided, and even if it does not rely on skilled workers, the apparatus can be used for the primary for gas insulated current transformers. The conductor 10 can be made. It can also eliminate concerns associated with the withdrawal of skilled workers. The conductor 1a may be formed by a spiral conductive portion, and the shape of the spiral is not limited to an annular shape or a rectangular shape. The conductive portion is not limited to the gas insulated current transformer primary conductor as long as the conductive portion is a coil formed of aluminum or an aluminum alloy.

  In addition, the resin 2 is filled in the spiral through groove 3 and fixes the side surfaces of the adjacent through grooves 3. Further, the resin 2 also fixes between the conductors of the two conductors 1a. The resin 2 is filled in the space between the conductors of the two conductors 1a and in the through groove 3 of the conductor 1a, so the two conductors 1a are fixed. As a result, a certain insulation distance that does not cause a short circuit between the two conductors 1a is secured, and even if the electromagnetic mechanical force is generated by the current within the allowable range that flows in a short time, the single conductor has strength to withstand deformation. doing. Therefore, with respect to the two conductors 1a, there is no need for reinforcement tape winding or storage in a metal case.

  Further, in the first embodiment, the flat surfaces of the two conductors 1a are arranged to face each other. In this case, the gas insulated current transformer primary conductor 10 can form a total of 12 turns of a primary energization circuit by the two conductors 1 a. Thereby, even if it is the 12-turn gas insulated current transformer primary conductor 10, the insulation work and winding work of the rectangular copper wire etc. by manual work can be eliminated.

  In the first embodiment, the terminal connection portion 4a is provided at the outer peripheral end of the conductor 1a, and the connection surface 6 is provided at the central end of the conductor 1a. The connection surface 6 is connected at the central end of the conductor 1a by fastening or welding to the other conductor 1a, and two conductors 1a are connected in series. In this case, in the two conductors 1a, the terminal connection portion 4a of one conductor 1a is adjacent to the projection 5a of the other conductor 1a, and the conductor connection portion 4a of the other conductor 1a is one output connection terminal. Since the input / output terminal can be formed in the vicinity of 4a, it is easy to connect the primary conductor 10 to the lead wire 11. Moreover, the connection of the two conductors 1a is also easy.

  Further, in the first embodiment, the corners and corners of the outer periphery of the two conductors 1a are diagonally set so that the outline of the cross section of the conductor 1a becomes circular with the flat surfaces of the two conductors 1a facing each other. I was shaving. Since the electric field concentration on the surface of the conductor 1a can be suppressed by making the outline of the cross section of the two conductors 1a circular, the electric field relaxation shield which has been required in the prior art becomes unnecessary.

  Further, in the first embodiment, only the central portion of the conductor 1 a is filled and fixed in the range to be filled with the resin 2 and the range to be fixed. When the resin 2 is filled up to the surface of the two conductors 1a, the resin 2 filled in the vicinity of the surface of the conductor 1a becomes triple junctions with different dielectric constants, and electric field concentration tends to occur. Therefore, in order to avoid the concentration of the electric field, for example, it is desirable that the resin 2 be recessed 5 mm or more from the surface of the conductor 1 a.

(Modification 1)
The number of radially extending turns of the conductor 1a may be changed according to the application and performance of the gas-insulated current transformer. As shown in FIG. 8, for example, the number of turns of the conductive portion constituting the conductor 1a is 3 turns in the radial direction. By connecting two pieces of the conductors 1a in series, a total of six turns of the primary conductor 10 can be obtained. In addition, a total of 10 turns of the primary conductor 10 may be formed with 5 turns in the radial direction and 2 turns in the axial direction, or a total of 14 turns with 7 turns in the radial direction and 2 turns in the axial direction. The conductor 10 may be formed. As described above, according to this primary conductor 10, it is possible to easily create an arbitrary number of turns of the primary conductor 10 by changing the digging program and the casting mold by the 3D processing machine.

(Modification 2)
FIG. 9 is a partial cross-sectional view showing a second modification of the gas insulated current transformer primary conductor 10 according to the first embodiment. As shown in FIG. 9, the resin 2 is added between the through groove 3 of the conductor 1a and the two conductors 1a, and is filled so as to integrally cover the surfaces of the two conductors 1a. As an example, the resin 2 covers the entire outer peripheral surface of the two conductors 1 with a thickness of 3 mm or more.

  The resin 2a covering the surfaces of the two conductors 1a suppresses electron emission from the surfaces of the two conductors 1a. Therefore, the withstand voltage performance of the primary conductor 10 is improved. Further, by optimizing the dielectric constant of the resin 2 and the thickness of the resin 2, equipotential lines of an electric field in the vicinity of the surfaces of the two conductors 1a are pushed out of the conductor 1a. Thereby, the electric field concentration to penetration groove 3 which is easy to be concentrated can be suppressed. That is, since the insulation performance of the primary conductor 10 is enhanced by the resin 2 covering the entire outer peripheral surface of the two conductors 1a, the miniaturization of the gas-insulated current transformer primary conductor 10 can be achieved. In addition, since the through groove 3 is completely covered by the resin 2, it is possible to withstand an improvement in withstand voltage performance or an occurrence of an abnormal voltage due to the occurrence of a lightning surge or a lightning surge.

(Modification 3)
FIG. 10 is a partial cross-sectional view showing a third modification of the gas insulated current transformer primary conductor 10 according to the first embodiment. As shown in FIG. 10, in the primary conductor 10, the resin 2 is added between the through groove 3 of the conductor 1a and the two conductors 1a, and is filled so as to integrally cover the surfaces of the two conductors 1a. Ru. And the slit 7 is penetratingly provided in the resin layer of resin 2a with which it filled with the conductor 1a of 2 sheets. The slit 7 has an opening on the inner peripheral surface and the outer peripheral surface of the primary conductor 10. The slits 7 allow gas to flow between the two conductors 1 a and effectively cool the space between the two conductors 1 a. For example, the slit 7 may penetrate from the secondary conductor 14 (not shown) toward the high voltage charging unit 19 (for example, in the top-bottom direction). Since a chimney effect arises by this, a cooling effect can be heightened.

Second Embodiment
(2-1. Configuration)
FIG. 11 is a partial cross-sectional view showing the structure of the gas insulated current transformer primary conductor 10 according to the second embodiment. As shown in FIG. 11, the electroconductive film layer 8 which covers resin 2a which covers the surface of the conductor 1a of 2 sheets further is provided. In other words, in the second embodiment, the primary conductor 10 is double covered with the inner shell resin 2 a and the outer conductive coating layer 8.

  FIG. 12 (a) is a front view of the primary conductor 10, and FIG. 12 (b) is a cross-sectional view taken along line B-B in FIG. 12 (a). As shown in FIG. 12, annular insulating bands 9 a and 9 b are formed on the conductive film layer 8. The insulating band 9a and the insulating band 9b are formed on closed curved surfaces (merids and latitudes: meridian, longitude) in two directions. That is, the insulating band 9a is formed over 360 degrees along the circumference of the small circle of the torus body in which the small circles are continuously connected in a ring shape to form a large circle, and is directed to the central axis of the primary conductor 10. Extend. The insulating band 9b is an annular ring coaxial with the conductor 1a, and is formed over 360 degrees along the great circle of the torus body.

(2-2. Operation and effect)
In the second embodiment, the conductive film layer 8 functions as an electric field shield of the primary conductor 10 by forming the conductive film layer 8 on the surface of the resin 2a. As a result, since the surface electric field of the resin 2a can be suppressed low, the distance to the pressure vessel and the secondary conductor which is the ground potential can be shortened, and the primary conductor 10 can be further miniaturized. . Further, since the inside of the conductive film layer 8 is completely shielded, it is possible to prevent the occurrence of corona discharge due to the void defect and the foreign matter mixing due to the air bubbles mixing in the resin 2a.

  In addition, when current flows in the two conductors 1a which are the primary conductors 10, an induced current flows in the secondary conductor 14 through the magnetic flux of the iron core. For example, in FIG. 12A, when current flows counterclockwise in the primary conductor 10, magnetic flux is generated from the back side to the front side of the sheet at the center of the primary conductor 10. When the insulating band 9a is not provided, a circulating primary current is generated in the conductive film layer 8 due to the primary current flowing through the primary conductor. Moreover, the conductive film layer 8 can suppress the eddy current accompanying the change of a magnetic field, and can make heat generation low by making electric conductivity low.

  Furthermore, the conductive film layer 8 and the lead wire 11 may be connected. By connecting the conductive film layer 8 and the lead wire 11, the charge charged in the conductive film layer 8 can be released to the lead wire 11, and the conductive film layer 8 and the lead wire 11 have an equal potential. Can. In other words, in order to prevent the charge from being accumulated in the conductive film layer 8 and to prevent the conductive film layer 8 from floating, the lead wire 11 or the like is connected.

  According to at least one embodiment described above, it is possible to provide a coil that can be produced by the device without resorting to skilled workers.

[Other embodiments]
While certain embodiments have been described, these embodiments have been presented by way of example only, and are not intended to limit the scope of the invention. These novel embodiments can be implemented in various other forms, and various omissions, substitutions, and modifications can be made without departing from the scope of the invention. These embodiments and modifications thereof are included in the scope and the gist of the invention, and are included in the invention described in the claims and the equivalents thereof.

  For example, in the first embodiment, although the primary conductor 10 is connected to the high voltage charging portion 19 of the gas-insulated current transformer 20 through the lead wire 11 in FIG. good. For example, the high voltage charging portion 19 and the terminal connection portion 4a of the primary conductor 10 may be directly connected.

1a ... conductor,
2 ... Resin,
3 ... Through groove,
4a ... terminal connection portion,
5a ... projection,
6 ... connection surface,
7 ... slit,
8 ... Conductive coating layer,
9a, 9b ... insulation band

Claims (8)

A conductor made of a conductive portion of aluminum or aluminum alloy spirally extending along the same plane;
A through groove extending spirally between the conductive portions and continuously penetrating the front and back of the conductor;
A resin filled in the through groove;
To provide
A coil characterized by The conductor is
Comprising a conductive portion of an aluminum alloy to which magnesium and silicon are added,
The coil according to claim 1, characterized in that The resin is
Covering the surface of the conductor in addition to the through groove;
The coil according to claim 1 or 2, characterized by Equipped with 2 pieces of the conductor,
Each of the two conductors is
A terminal connection portion provided at a radially outer side end portion of the conductive portion;
A connecting surface provided at a spiral center side end of the conductive portion;
Have
The two conductors are
It is arranged facing each other, leaving a predetermined space,
The connection surfaces of each other are connected to each other,
Having an input / output terminal at the terminal connection portion;
The coil according to any one of claims 1 to 3, characterized by A resin layer filled between the two conductors;
Vent holes penetrating the resin layer;
Further comprising
The coil according to claim 4, characterized in that Further comprising a conductive coating layer overlaid on the resin covering the surface of the conductor;
The coil according to claim 3, characterized in that Further comprising an annular insulating band coaxial with the conductor on the surface of the conductive coating layer;
The coil according to claim 6, characterized in that The surface of the conductive coating layer may further include an insulating band extending toward a central axis of the conductor.
The coil according to claim 6 or 7, characterized by

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