JP2015177611A - Stationary induction electric apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a stationary induction electric apparatus which reduces the risk of insulation breakdown of an insulation oil in the vicinity of a spacer.SOLUTION: A stationary induction electric apparatus includes: a cylindrical pedestal connected to a casing and communicated with the inside of the casing; a cylindrical bushing pocket connected with the pedestal; a tabular insulation spacer partitioning the pedestal and an internal space of the bushing pocket; a through-conductor penetrating the insulation spacer; a lead connecting a body of the stationary induction electric apparatus and the through-conductor; and one or more cylindrical insulation members each disposed in a concentric cylindrical shape with the lead as a center axis and including an end opposing the insulation spacer.

Description

  Embodiments described herein relate generally to a static induction electrical device.

  Stationary induction electrical devices such as transformers and reactors are used in the middle of a system that transmits power from a power plant to a consumer such as a factory, building, or household. In a static induction electrical device, for example, a static induction electrical device main body (main body such as a transformer or a reactor) is insulated using a liquid insulating medium (insulating oil or the like).

Here, when a rectifier thyristor is connected to a static induction electrical device, an air bushing is generally used.
In addition, when directly connecting a device that uses SF ₆ gas as an insulating medium to a static induction electrical device, in order to reduce the installation space, the air bushing is omitted, and the insulating oil and the insulating oil or the insulating material are used by using a spacer. It may be connected by partitioning oil and insulating gas (see Patent Document 1).
However, in such a case, it has been found that the insulating oil may break down in the vicinity of the spacer.

JP 2011-139571 A

  It is an object of the present invention to provide a static induction electrical device that is capable of reducing the occurrence of insulation breakdown caused by insulating oil in the vicinity of a spacer.

  A stationary induction electrical device according to an embodiment includes a casing that covers a stationary induction electrical device main body, a cylindrical base that is connected to the casing and communicates with the inside of the casing, and a cylindrical base that is connected to the base. A cylindrical bushing pocket having a second internal space, one end connected to the bushing pocket, and the other end provided with a terminal, the first internal space, and the second Connecting the plate-like insulating spacer, the penetrating conductor penetrating the insulating spacer, the static induction electrical device main body and the penetrating conductor, at least a part of which is the first inner portion. A lead disposed in the space, connecting the terminal and the through conductor, and at least a portion disposed in the second internal space, and a connection conductor in the first internal space, Lee The concentrically arranged cylindrical shape around axis, having an end facing the insulating spacer comprises one or a plurality of tubular insulating member.

  ADVANTAGE OF THE INVENTION According to this invention, the static induction electric equipment which aimed at reduction of the fall which insulation oil breaks down in the vicinity of a spacer can be provided.

1 is a schematic cross-sectional view showing a static induction electrical device according to a first embodiment. 1 is an enlarged schematic cross-sectional view showing a part of a static induction electrical device according to a first embodiment. It is a figure which shows an example of the voltage waveform applied to a static induction electrical apparatus. It is an expansion schematic cross section which shows a part of static induction electric equipment which concerns on 2nd Embodiment. It is an expansion schematic cross section which shows a part of static induction electric equipment which concerns on 3rd Embodiment.

  Hereinafter, an embodiment of a stationary induction electrical device connecting apparatus will be described in detail with reference to the drawings.

(First embodiment)
FIG. 1 and FIG. 2 are a schematic cross-sectional view showing the static induction electrical device 10 according to the first embodiment and an enlarged schematic cross-sectional view in which a part thereof is enlarged.
The static induction electrical device 10 includes a static induction electrical device main body portion 20, an air bushing portion 30, a pedestal portion 40, and a bushing pocket portion 50, and is connected to the thyristor Thr.

  The static induction electrical device main body 20 includes a static induction electrical device main body 21, a casing 22, an insulating medium 23, an opening 25, leads 26, and terminals 27.

  The stationary induction electrical device main body 21 is a device that operates by static induction in a stationary state, such as a transformer or a reactor. Here, it is assumed that the stationary induction electrical device main body 21 is a transformer.

  The casing 22 is an outer shell that covers the stationary induction electrical device main body 21 and protects it from the outside. The casing 22 includes an upper plate 22a, a bottom plate 22b, a side plate 22c, and a swash plate 22d. The upper plate 22a, the bottom plate 22b, the side plate 22c, and the swash plate 22d are respectively arranged in the upward direction, the downward direction, the lateral direction, and the diagonally upward direction of the stationary induction electrical device main body 21. The casing 22 has an internal space for holding the stationary induction electrical device main body 21.

  An insulating medium 23 is filled in the internal space of the casing 22. For the insulating medium 23, insulating oil (mineral oil, silicon oil, ester oil, rapeseed oil, etc.) can be used.

  The opening 25 is for connecting the pedestal 40 to the stationary induction electrical device main body 20. Here, the opening 25 is disposed on the upper plate 22a. However, the opening 25 may be arranged in the side plate 22c or the swash plate 22d. That is, the attachment position and the attachment angle of the base part 40, the bushing pocket part 50, and the air bushing part 30 with respect to the casing 22 are not ask | required.

  The lead 26 is a conductor that supplies power to the stationary induction electrical device main body 21. The lead 26 extends from the stationary induction electrical device main body 21 toward the opening 25. A part of the lead 26 is disposed inside the pedestal 40 (pedestal 41). A terminal 27 is connected to the tip of the lead 26.

  The air bushing 30 includes a soot tube 31, a connection conductor 32, and a terminal 33.

  The bushing 31 is for protecting the connection conductor 32 from the outside, and is composed of an inorganic insulating material (ceramic, etc.), a polymer insulating material (FRP (Fiber Reinforced Plastics), silicone, etc.). Is done. The soot tube 31 has one end connected to the bushing pocket 51, the other end including the terminal 33, and a through hole through which the connection conductor 32 passes.

  The connection conductor 32 is a conductor that electrically connects the terminal 33 and a through conductor 43 described later. The connection conductor 32 has a substantially columnar shape (for example, a substantially columnar shape), and has one end connected to the terminal 33 and the other end connected to the through conductor 43. A part of the connection conductor 32 is disposed inside the bushing pocket 50 (bushing pocket 51).

The terminal 33 is a columnar (for example, cylindrical) conductor, is connected to the thyristor Thr, and introduces electric power from the thyristor Thr to the stationary induction electrical apparatus 10.
FIG. 3 is a graph showing the voltage waveform Vw applied to the terminal 33. This voltage waveform Vw is a combination (superimposed) of the AC voltage Vac and the DC voltage Vdc. The AC voltage Vac is an AC voltage converted into a predetermined voltage by the winding of the stationary induction electrical device main body 21. The DC voltage Vdc is a DC voltage rectified by the thyristor Thr. The voltage waveform Vw is applied from the terminal 33 to the connection conductor 32 and the lead 26. The DC voltage Vdc is, for example, ± 250 to ± 800 kV (for example, +500 kV), and the AC voltage Vac is an effective value, for example, 154 to 550 kV.

  As described above, the application of the voltage waveform Vw in which direct current and alternating current are combined (superimposed) increases the possibility that the insulating media 23 and 53 are broken down in the vicinity of the insulating spacer 42. Details of this will be described later.

  The pedestal portion 40 includes a pedestal 41, an insulating spacer 42, a through conductor 43, and a tubular insulating member 44.

The pedestal 41 has a cylindrical shape (substantially cylindrical shape or the like) and is connected to the casing 22. The pedestal 41 has an internal space that communicates with the inside of the casing 22. For this reason, the inside (internal space) of the base 41 is filled with the insulating medium 23 as in the case of the casing 22. The connection conductor 32 is disposed on the substantially central axis of the substantially cylindrical pedestal 41.
The pedestal 41 is basically composed of a conductor such as metal and has a ground potential.

  The insulating spacer 42 partitions (divides) the internal space of the base 40 (base 41) and the internal space of the bushing pocket 50 (bushing pocket 51). The insulating spacer 42 has a substantially plate shape and can be made of a resin material (epoxy resin, melamine resin, unsaturated polyester resin, polyimide resin, phenol resin, etc.).

  The insulating spacer 42 includes a substantially hollow disk-shaped connecting portion 42a, a substantially disk-shaped flat plate portion 42b, and a transition portion 42c having a substantially truncated cone shape. The connecting portion 42 a is for connecting the bushing pocket portion 50 to the air bushing portion 30 and the stationary induction electrical device main body portion 20. A through conductor 43 is attached to the flat plate portion 42b. The transition part 42c connects the connecting part 42a and the flat plate part 42b. The insulating spacer 42 can be a direct current one.

  The through conductor 43 penetrates the insulating spacer 42 (flat plate portion 42b), and electrically connects the pedestal portion 40 (stationary induction electrical device main body portion 20) and the bushing pocket portion 50 (air bushing portion 30).

The upper and lower portions of the through conductor 43 are disposed in the internal space of the bushing pocket 51 and the internal space of the base 41, respectively.
The upper part of the through conductor 43 has a shape corresponding to the lower ends of the connection conductor 32 and the soot tube 52, and is removably engaged with the lower ends of the connection conductor 32 and the soot tube 52.
The lower portion of the through conductor 43 has a shape corresponding to the terminal 27 and is electrically connected to the terminal 27.

  The bushing pocket portion 50 includes a bushing pocket 51, a soot tube 52, an insulating medium 53, and a cylindrical insulating member 54. The bushing pocket portion 50 is detachably connected to the pedestal portion 40. As described later, since the bushing pocket portion 50 can be detached from the pedestal portion 40, the stationary induction electrical device 10 can be easily installed.

The bushing pocket 51 has a cylindrical shape (substantially cylindrical shape or the like) and is detachably installed from the pedestal 41. The lead 26 and the terminal 27 are arranged on the substantially central axis of the substantially cylindrical bushing pocket 51.
The bushing pocket 51 is basically composed of a conductor such as metal and has a ground potential.
The bushing pocket 51 is filled with an insulating medium 53. The insulating medium 53 is made of an insulating oil (mineral oil, silicon oil, ester oil, rapeseed oil, etc.), like the insulating medium 23. The insulating medium 23 and the insulating medium 53 are both made of insulating oil, but the types may be the same or different.

  The soot tube 52 (bushing) is for protecting the connection conductor 32, and is composed of an inorganic insulating material (ceramic, etc.), a polymer insulating material (FRP (Fiber Reinforced Plastics), silicone, etc.). . The soot tube 52 has a through hole through which the connection conductor 32 passes. The soot tube 52 can be a direct current one.

A plurality of concentric cylindrical tubular insulating members 44 and 54 are attached to both sides of the insulating spacer 42 so that the end surfaces thereof face the insulating spacer 42. The plurality of cylindrical insulating members 44 are arranged in a concentric cylindrical shape with the lead 26 as the central axis. The plurality of cylindrical insulating members 54 are arranged in a concentric cylindrical shape with the connecting conductor 32 as the central axis.
However, the cylindrical insulating members 44 and 54 can have a shape other than the concentric cylindrical shape except the vicinity of the insulating spacer 42.
For the cylindrical insulating members 44 and 54, a fibrous laminate (for example, a press board (a laminate of plant fibers)), plastic, or the like can be used.

Here, the cylindrical insulating member 44 is fixed to the lead 26 in the vicinity of the stationary induction electrical device main body 21. For example, the tubular insulating member 44 can be tied to the lead 26 and fixed using an insulating wire.
The cylindrical insulating member 54 is fixed to the soot tube 52 in the vicinity of the uppermost portion inside the bushing pocket 51. For example, the tubular insulating member 54 can be tied to the soot tube 52 and fixed using an insulating wire.
However, other methods can be appropriately employed for fixing the cylindrical insulating members 44 and 54.

  End portions of the cylindrical insulating members 44 and 54 are opposed to the insulating spacer 42. At this time, it is preferable that the distances d1 and d2 between the end portions of the plurality of cylindrical insulating members 44 and 54 and the insulating spacer 42 are substantially constant. That is, as will be described later, in order to reduce the concentration of the electric field in the vicinity of the insulating spacer 42, the distances d1 and d2 between the end portions of the cylindrical insulating members 44 and 54 and the insulating spacer 42 are about 10 to 50 mm. It is preferable (more preferably, the distances d1 and d2 are about 10 to 20 mm).

  However, the distance d1 between the cylindrical insulating member 44 and the insulating spacer 42 and the distance d2 between the cylindrical insulating member 54 and the insulating spacer 42 do not necessarily need to match. In particular, when the insulating media 23 and 53 are made of different materials, the distances d1 and d2 generally do not match.

  Here, although the example which has arrange | positioned the three cylindrical insulation members 44 and 54 is shown, respectively, the number is not specifically limited. For example, only one or five or more cylindrical insulating members 44 and 54 can be arranged. Note that the number of the cylindrical insulating members 44 and 54 may be different.

  As shown below, this configuration prevents dielectric breakdown of the insulating media 23 and 53 in the vicinity of the insulating spacer 42.

As described above, the voltage waveform Vw combining direct current and alternating current is applied to the connection conductor 32 and the lead 26. For this reason, it is necessary for the insulating media 23 and 53 not to cause dielectric breakdown with respect to both direct current and alternating current.
Here, in the case of direct current, the current tends to concentrate at a location where the resistivity is small, and in the case of alternating current, the electric field tends to concentrate at a location where the dielectric constant is large.

  The insulating spacer 42 is solid and generally has a relatively higher resistivity and dielectric constant than the insulating media 23 and 53 that are liquid (insulating oil). For this reason, the vicinity of the insulating spacer 42 becomes a boundary between the insulating media 23 and 53 having a high current density and the insulating spacer 42 having a high electric field strength. As a result, the electric field is concentrated on the insulating media 23 and 53 in the vicinity of the insulating spacer 42. there is a possibility.

  In this way, when a voltage waveform Vw that combines direct current and alternating current is applied to the connection conductor 32 and the lead 26, the electric field concentrates on the insulating media 23 and 53 in the vicinity of the insulating spacer 42, and dielectric breakdown may occur. There is sex.

  The substantially concentric cylindrical insulating members 44 and 54 having the connecting conductor 32 and the lead 26 as the central axes alleviate the concentration of the DC electric field in the vicinity of the insulating spacer 42 and improve the AC dielectric strength. As a result, the dielectric breakdown of the insulating media 23 and 53 is prevented.

The cylindrical insulating members 44 and 54 are solid, and generally have a relatively higher resistivity and dielectric constant and a higher dielectric breakdown electric field than the insulating media 23 and 53. On the other hand, the insulating media 23 and 53 that are liquids generally have a tendency that the AC breakdown electric field becomes smaller as the volume to which the AC electric field is applied is larger.
For this reason, the volumes of the insulating media 23 and 53 are divided by the cylindrical insulating members 44 and 54, and the dielectric breakdown due to the alternating electric field of the insulating media 23 and 53 is prevented.

  Further, since the cylindrical insulating members 44 and 54 have a relatively high resistivity, the DC electric field tends to concentrate more than the insulating media 23 and 53. As shown in FIG. 2, the DC electric field E concentrated on the cylindrical insulating members 44 and 54 spreads from the end portions of the cylindrical insulating members 44 and 54 toward the insulating spacer 42 that faces the DC electric field E. As a result, the concentration of the DC electric field near the insulating spacer 42 is alleviated. As described above, the cylindrical insulating members 44 and 54 prevent the dielectric breakdown due to the AC electric field in the insulating media 23 and 53 and reduce the concentration of the DC electric field in the vicinity of the insulating spacer 42, The dielectric breakdown of 53 is prevented.

The static induction electrical device 10 according to the present embodiment has the following advantages.
(1) Improvement of workability Workability at the time of installation of the stationary induction electrical device 10 and replacement of the soot tube 52 is improved. As described above, the bushing pocket portion 50 and the air bushing portion 30 can be detached from the pedestal portion 40. The interior of the base 41 and the casing 22 can be sealed by the insulating spacer 42 even after the bushing pocket portion 50 and the like are removed.

  For this reason, by setting the insulating spacer 42 to the pedestal 41 when shipped from the factory, it is possible to attach and replace the soot tube 52 without opening the casing 22 and the pedestal 41 at the place where the stationary induction electrical device 10 is installed. As a result, the working time can be shortened compared to the case where the casing 22 needs to be opened. Further, it is possible to reduce the possibility that the inside of the casing 22 is contaminated with dust during operation.

(2) Improvement of insulation strength The insulation performance of the static induction electrical device 10 is improved. By disposing solid cylindrical insulating members 44 and 54 (with a relatively large dielectric constant) in insulating media 23 and 53 (with a relatively small dielectric constant) using insulating oil, the volume of the media 23 and 53 can be reduced. By dividing, the AC dielectric strength is improved, and the DC electric field is concentrated on the cylindrical insulating members 44 and 54. The DC electric field concentrated on the cylindrical insulating members 44 and 54 spreads toward the insulating spacer 42. As a result, the concentration of the DC electric field in the vicinity of the insulating spacer 42 is alleviated (uniformized), and the dielectric breakdown of the insulating media 23 and 53 is prevented.

(Second Embodiment)
FIG. 4 is an enlarged schematic cross-sectional view in which a part of the static induction electrical device 10a according to the second embodiment is enlarged.

The static induction electrical device 10a is different from the static induction electrical device 10 in the following points (1) and (2).
(1) At the ends of the cylindrical insulating members 44 and 54, annular insulating members 45 and 55 are added. That is, the end portions of the cylindrical insulating members 44 and 54 are thicker than the center portion thereof.

(2) In the vicinity of the connecting conductor 32 and the lead 26, the thickness t of the plurality of cylindrical insulating members 44 and 54 is small and the interval g is large (the number density (per unit length at the distance r from the central axis). In the vicinity of the base 41 and the bushing pocket 51, the thickness t is large and the interval g is small (the number density is large). That is, the thickness increases in the order of thickness t1 <t2 <t3. Further, the interval is large in the order of the interval g2 <g1. That is, the thickness t of the cylindrical insulating members 44 and 54 is larger in the order of their diameters. Further, the interval g between the cylindrical insulating members 44 and 54 is larger in the order of their diameters.

By doing in this way, the insulation performance of the static induction electric equipment 10 can further be improved.
By adding the annular insulating members 45 and 55, the contact portions between the cylindrical insulating members 44 and 54 and the insulating media 23 and 53 are enlarged, so that the electric field is concentrated at the distal ends of the cylindrical insulating members 44 and 54. Can be more relaxed.

Further, the concentration of the electric field in the vicinity of the connection conductor 32 and the lead 26 can be reduced.
As described above, the connection conductor 32 (charging side) is disposed on the substantially central axis of the substantially cylindrical base 41 (grounding side). Further, the lead 26 and the terminal 27 (charge side) are arranged on the substantially central axis of the substantially cylindrical bushing pocket 51 (ground side). Thus, when the charge side and ground side electrodes are arranged with rotational symmetry (the electrodes are cylindrical), the electric field changes according to the distance from the central axis. That is, the closer to the central axis, the larger the electric field, and the further away from the central axis, the smaller the electric field.

  The uniformity of the electric field can be improved by changing the thickness t and the interval g of the cylindrical insulating members 44 and 54 according to the distance r from the central axis. That is, utilizing the characteristic that the generated potential concentrates on the cylindrical insulating members 44 and 54, a thin press board is sparsely arranged near the electrodes, and the thick cylindrical insulating members 44 and 54 are densely arranged near the ground plane. By doing so, the electric field on the surface of the insulating spacer 42 in the vicinity of the electrode can be relaxed.

(Third embodiment)
FIG. 5 is an enlarged schematic cross-sectional view in which a part of the static induction electrical device 10b according to the third embodiment is enlarged.

The static induction electrical device 10b is different from the static induction electrical device 10 in the following points.
(1) The soot tube 31 of the air bushing 30 is made of a polymer insulating material, and the insulating medium 53b inside the bushing pocket 51 is made of SF ₆ gas. Further, the soot tube 52 is not used.
In this embodiment, the cylindrical insulating member 54 is disposed in the gaseous insulating medium 53b to reduce the concentration of the electric field, but this is not always necessary. Unlike the liquid case, the gaseous insulating medium 53b has a high resistivity, so that it is difficult for current to flow and it is difficult for dielectric breakdown to occur. That is, the necessity of the cylindrical insulating member 54 in the air (insulating medium 53b) is smaller than that in the liquid (insulating medium 53).
(2) The slide contact 56 is used to connect the connection conductor 32 and the insulating spacer 42.

  The slide contact 56 has a spring mechanism 57 disposed in the recess. The connection conductor 32 is inserted into the recess. The spring mechanism 57 is detachably engaged with the connection conductor 32.

The static induction electrical apparatus 10b according to the present embodiment has the following advantages.
(1) Weight reduction of static induction electrical equipment 10b Static induction electrical equipment 10 is reduced in weight. By using a polymer insulating material for the soot tube 31b, using SF ₆ gas for the insulating medium 53b, and not using the soot tube 52, compared to the case where an inorganic insulating material such as ceramic is used for the soot tube 31b, the air bushing 30b and The bushing pocket part 50b can be reduced in weight.
The reduction in weight of the static induction electrical device 10 leads to improvement in workability and transportability. Furthermore, the seismic performance of the static induction electrical device 10 is improved. The inertial force that the soot pipe 52 receives when an earthquake occurs is smaller than the conventional one, and the damage of the soot pipe 52 due to the earthquake can be prevented.

(2) Improvement of workability Workability at the time of installation of the stationary induction electrical apparatus 10b is improved. That is, the working time can be further shortened by connecting to the connection conductor 32 a using the slide contact 56.
Moreover, by not using the soot tube 52, the bushing pocket part 50b is simplified and the workability | operativity at the time of installation of the stationary induction | guidance | derivation electrical equipment 10b is improved.

  Although several embodiments of the present invention have been described, these embodiments are presented by way of example and are not intended to limit the scope of the invention. These novel embodiments can be implemented in various other forms, and various omissions, replacements, and changes can be made without departing from the scope of the invention. These embodiments and modifications thereof are included in the scope and gist of the invention, and are included in the invention described in the claims and the equivalents thereof.

DESCRIPTION OF SYMBOLS 10 Static induction electrical equipment 20 Static induction electrical equipment main part 21 Static induction electrical equipment main part 22 Casing 22a Top plate 22b Bottom plate 22c Side plate 22d Swash plate 23 Insulating medium 23, 53 Insulating medium 25 Opening part 26 Lead 27 Terminal 30 Air bushing part 31 Barrel pipe 32 Connection conductor 33 Terminal 40 Base part 41 Base 42 Insulating spacer 42a Connecting part 42b Flat plate part 42c Transition part 43 Through conductors 44 and 54 Cylindrical insulating members 45 and 55 Annular insulating member 50 Bushing pocket part 51 Bushing pocket 52 Barrel pipe 53 Insulating medium 56 Slide contact 57 Spring mechanism

Claims (14)

A casing covering the stationary induction electrical device body;
A cylindrical base connected to the casing and having a first internal space communicating with the inside of the casing;
A cylindrical bushing pocket connected to the pedestal and having a second internal space;
A soot tube having one end connected to the bushing pocket and the other end provided with a terminal;
A plate-like insulating spacer that separates the first internal space and the second internal space;
A through conductor penetrating the insulating spacer;
A lead connecting the stationary induction electrical device main body and the through conductor, and at least a portion thereof being disposed in the first internal space;
A connecting conductor connecting the terminal and the penetrating conductor, at least part of which is disposed in the second internal space;
One or a plurality of cylindrical insulating members disposed in a concentric cylindrical shape with the lead as a central axis in the first internal space, and having an end facing the insulating spacer;
A static induction electrical device comprising: The static induction electrical apparatus according to claim 1, comprising a plurality of the cylindrical insulating members having different diameters. The static induction electrical apparatus according to claim 2, wherein the thickness of the plurality of cylindrical insulating members is larger in order of diameter. The static induction electrical apparatus according to claim 2 or 3, wherein an interval between the plurality of cylindrical insulating members is larger in order of diameter. The stationary induction electrical apparatus according to any one of claims 1 to 4, wherein an end portion of the cylindrical insulating member is thicker than a central portion of the cylindrical insulating member. A second soot tube disposed in the second internal space and having a through-hole through which the connection conductor passes;
One or a plurality of second cylindrical insulating members disposed in a concentric cylindrical shape with the connection conductor as a central axis in the second internal space and having an end facing the insulating spacer;
The static induction electrical apparatus according to any one of claims 1 to 5, further comprising: The static induction electrical apparatus according to claim 6, comprising a plurality of the second cylindrical insulating members having different diameters. The static induction electrical apparatus according to claim 7, wherein a thickness of the plurality of second cylindrical insulating members is larger in order of diameter. The static induction electrical apparatus according to claim 7 or 8, wherein an interval between the plurality of second cylindrical insulating members is small in order of diameter. 10. The static induction electrical device according to claim 6, wherein an end portion of the second cylindrical insulating member is thicker than a central portion of the second cylindrical insulating member. The static induction electrical apparatus according to claim 1, wherein the cylindrical insulating member is a press board. The soot tube is made of a polymer insulating material,
The stationary induction electrical apparatus according to any one of claims 1 to 11, further comprising SF ₆ gas serving as an insulating medium filled in the second internal space. The bushing pocket is detachable from the pedestal;
The slide contact further includes a recess disposed in the second internal space and into which the connection conductor is inserted, and a spring mechanism disposed in the recess and detachably engaged with the connection conductor. Do,
The static induction electrical apparatus according to any one of claims 1 to 12. A voltage waveform in which a DC voltage and an AC voltage are superimposed is applied to the terminal.
The stationary induction electrical apparatus according to any one of claims 1 to 13.

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