JP5031079B2 - Switchgear - Google Patents

Description

  The present invention relates to a switchgear used in power transmission / distribution and power receiving facilities, and more particularly to a main circuit conductor disposed therein and an electric field relaxation means thereof.

  The main circuit conductor in the conventional switchgear and the insulating layer as the electric field relaxation means have the configuration shown in FIG. This figure shows the main circuit conductor 25 for two phases among the main circuit conductors for three phases, and shows a state in which the main circuit conductor 25 extends in a direction perpendicular to the paper surface.

  Each main circuit conductor 25 is disposed at a predetermined interval, and the front end portion of each main circuit conductor 25 is a curved surface, and an insulating layer 26 is provided on each curved surface portion. An insulation barrier 27 is installed at an intermediate position of the main circuit conductor 25 and is fixed to the ground metal container 10.

By adopting such a configuration, the insulation characteristics between the main circuit conductors 25 are improved, and when there is no insulation barrier, a switch gear similar to the switch gear in which the SF6 gas is sealed is sealed with dry air. It was possible. (For example, refer to Patent Document 1).

JP 2000-341816 A

  The conventional switchgear is configured as described above, and the insulating layer 26 is formed on the curved surface at the tip of the main circuit conductor 25 so as to be in close contact with the main circuit conductor 25. There is a problem that processing is necessary and the cost for forming the insulating layer 26 is increased.

  In addition, since the end of the insulation barrier 27 installed between the main circuit conductors 25 has an edge shape, the distance h to the end of the insulation barrier is not so large with respect to the outer diameter of the main circuit conductor 25. As a result of the high electric field around the edge portion at the end of the insulating barrier 27, it is necessary to increase the insulating barrier 27 and h to prevent the breakdown voltage performance from deteriorating. There was also a problem that miniaturization became difficult.

  The present invention has been made to cope with the above-described problems, and does not require casting or the like for forming the insulating layer of the main circuit conductor, and improves the withstand voltage performance of the main circuit conductor. An object of the present invention is to provide a switchgear that can be used.

  The switchgear according to the present invention is disposed in an insulating gas sealed in a ground metal container, and forms a gap between the main circuit conductor having a curved surface at the tip and the main circuit conductor. And an insulating barrier that covers the entire curved surface, and a curved surface having a curvature of 1/2 or less of the thickness of the insulating barrier is formed at the end of the insulating barrier.

  The switchgear according to the present invention is configured as described above, and a curved surface is formed at the front end portion of the main circuit conductor to reduce the electric field on the surface of the main circuit conductor, and an insulating barrier covering the entire curved surface is provided along the curved surface. By suppressing the flashing from the surface of the main circuit conductor to the other, and forming a curved surface having a curvature of 1/2 or less of the thickness of the insulating barrier at the end of the insulating barrier, The electric field can be reduced and the withstand voltage performance can be improved.

  Furthermore, since the outer diameter of the main circuit conductor in the portion not covered with the insulating barrier is made smaller than the outer diameter of the main circuit conductor in the portion covered with the insulating barrier, the electric field at the end of the insulating barrier is reduced, Withstand voltage performance can be improved.

  Furthermore, the inner surface or the outer surface of the insulation barrier is composed of a first plane extending in the diametrical direction of the main circuit conductor and a second plane extending in the extending direction of the main circuit conductor, and the first plane and the second plane With the curved surface having a curvature smaller than that of the curved surface of the main circuit conductor, the withstand voltage performance can be improved.

  In addition, since the insulating barrier is made of an insulating material having a relative dielectric constant of 3 or less, such as Teflon (registered trademark) or polycarbonate, the electric field in the surface space of the insulating barrier can be reduced, and the withstand voltage performance is improved. be able to.

  In addition, since the insulation barrier is formed with a male screw or the like that can be screwed into the main circuit conductor, the main circuit conductor and the insulation barrier can be securely and firmly coupled, and a high electric field at the coupling portion can be suppressed. Therefore, the withstand voltage performance can be improved.

BRIEF DESCRIPTION OF THE DRAWINGS The structure of the main circuit conductor etc. which comprise the principal part of the switchgear by Embodiment 1 of this invention is shown, (a) is the schematic which shows the structure of a main circuit conductor and an insulation barrier, (b) is (a It is a figure which shows the electric potential distribution in the structure of (). FIG. 2 shows a configuration of main circuit conductors and the like constituting a main part of a switchgear according to Embodiment 2 of the present invention, wherein (a) is a schematic diagram showing configurations of a main circuit conductor and an insulation barrier, and (b) is (a). It is a figure which shows the electric potential distribution in the structure of (). FIG. 3 shows a configuration of main circuit conductors and the like constituting a main part of a switchgear according to Embodiment 3 of the present invention, in which (a) is a schematic diagram showing configurations of a main circuit conductor and an insulation barrier, and (b) is (a). It is a figure which shows the electric potential distribution in the structure of (). FIG. 7 shows the configuration of main circuit conductors and the like constituting the main part of a switchgear according to Embodiment 4 of the present invention, wherein (a) is a schematic diagram showing the configurations of the main circuit conductor and the insulation barrier, and (b) is (a). It is a figure which shows the electric potential distribution in the structure of (). FIG. 7 shows a configuration of main circuit conductors and the like constituting the main part of a switchgear according to Embodiment 5 of the present invention, in which (a) is a schematic diagram showing the configurations of the main circuit conductor and the insulation barrier, and (b) is (a). It is a figure which shows the electric potential distribution in the structure of (). FIG. 7 shows the configuration of main circuit conductors and the like constituting the main part of a switchgear according to Embodiment 6 of the present invention, wherein (a) is a schematic diagram showing the configurations of the main circuit conductor and the insulation barrier, and (b) is (a). It is a figure which shows the electric potential distribution in the structure of (). FIG. 20 shows a potential distribution in the seventh embodiment. FIG. 20 is a schematic diagram showing a configuration of a main circuit conductor and the like in the eighth embodiment. FIG. 20 is a schematic diagram illustrating a configuration of a main circuit conductor and the like in the ninth embodiment. It is the schematic which shows the structure of the main circuit conductor etc. in the conventional switchgear.

Embodiment 1 FIG.
Embodiment 1 of the present invention will be described below with reference to the drawings. 1A and 1B show the configuration of main circuit conductors and the like constituting the main part of the switchgear according to the first embodiment. FIG. 1A is a schematic diagram showing the configuration of a main circuit conductor and an insulation barrier, and FIG. It is a figure which shows the electric potential distribution in the structure of a).

  In FIG. 1A, a main circuit conductor 1 is a conductor constituting a main circuit such as a circuit breaker, a disconnecting switch, a grounding switch, or a three-position disconnecting switch having a grounding switching function added to the disconnecting switch. It is disposed in an insulating gas atmosphere such as SF6 gas, dry air, nitrogen, carbon dioxide, etc. enclosed in a grounded metal container 10 constituting the box of the switchgear.

  A curved surface 1a is formed at the tip of the main circuit conductor 1 facing the counter electrode of the same phase, the electrode of the other phase, or the ground metal container, and an insulating barrier 2 covering the entire curved surface along the curved surface 1a. And a slight gap. A curved surface 2 a having a curvature equal to or less than ½ of the thickness t of the insulating barrier is formed at the end of the insulating barrier 2.

  By adopting such a configuration, it can be recognized that the potential distribution on the curved surface 2a at the end of the insulating barrier is rough as shown in FIG. 1B, and the electric field in this portion is low. .

Embodiment 2. FIG.
Next, a second embodiment of the present invention will be described with reference to the drawings. 2A and 2B show the configuration of the main circuit conductor and the like in the second embodiment. FIG. 2A is a schematic diagram showing the configuration of the main circuit conductor and the insulation barrier, and FIG. 2B shows the potential distribution in the configuration of FIG. FIG.

  In these drawings, the same or corresponding parts as those in FIG. The difference from FIG. 1 is that, as shown in FIG. 2 (a), a protruding portion 2b protruding toward the main circuit conductor 1 is formed at the end of the insulating barrier 2, and the end of the insulating barrier including the protruding portion 2b is formed. This is the point that a curved surface 2c having a curvature of 1/2 or more of the thickness t of the insulating barrier is formed in the part.

  By adopting such a configuration, the potential distribution on the curved surface 2c at the end of the insulating barrier is further coarser than that in FIG. 1B as shown in FIG. 2B, and the electric field in this portion is further increased. You can see that it is lower.

Embodiment 3 FIG.
Next, a third embodiment of the present invention will be described with reference to the drawings. 3A and 3B show the configuration of the main circuit conductor and the like in the third embodiment. FIG. 3A is a schematic diagram showing the configuration of the main circuit conductor and the insulation barrier, and FIG. 3B shows the potential distribution in the configuration of FIG. FIG.

  In these drawings, the same or corresponding parts as those in FIG. The difference from FIG. 1 is that, as shown in FIG. 3 (a), a protruding portion 2d protruding on the opposite side of the side facing the main circuit conductor is formed at the end of the insulating barrier 2, and this protruding portion 2d is This is that a curved surface 2e having a curvature of 1/2 or more of the thickness t of the insulating barrier is formed at the end of the insulating barrier.

  By adopting such a configuration, the potential distribution on the curved surface 2e at the end of the insulating barrier is further coarser than that in FIG. 1B as shown in FIG. 3B, and the electric field in this portion is further increased. You can see that it is lower.

Embodiment 4 FIG.
Next, a fourth embodiment of the present invention will be described with reference to the drawings. 4A and 4B show the configuration of the main circuit conductor and the like in the fourth embodiment. FIG. 4A is a schematic diagram showing the configuration of the main circuit conductor and the insulation barrier, and FIG. 4B shows the potential distribution in the configuration of FIG. FIG.

  In these drawings, the same or corresponding parts as those in FIG. As shown in these drawings, the configuration of the insulation barrier 2 is the same as that of FIG. 1A, but the outer diameter of the conductor 1b in the portion of the main circuit conductor 1 not covered by the insulation barrier 2 is the insulation barrier 2. The point which is made smaller than the outer diameter of the covered conductor 1c is different from FIG.

  By adopting such a configuration, the potential distribution on the curved surface 2a at the end of the insulating barrier is further coarser than that in FIG. 1B as shown in FIG. 4B, and the electric field in this portion is further increased. You can see that it is lower.

Embodiment 5 FIG.
Next, a fifth embodiment of the present invention will be described with reference to the drawings. 5A and 5B show the configuration of the main circuit conductor and the like in the fifth embodiment. FIG. 5A is a schematic diagram showing the configuration of the main circuit conductor and the insulation barrier, and FIG. 5B shows the potential distribution in the configuration of FIG. FIG.

  In these drawings, the same or corresponding parts as in FIG. The difference from FIG. 4 is that the inner side surface of the insulation barrier 2 is composed of a first inner plane 2 f extending in the diameter direction of the main circuit conductor 1 and a second inner plane 2 g extending in the extending direction of the main circuit conductor 1. The first inner plane 2f and the second inner plane 2g are connected by a curved surface 2h having a curvature smaller than the curvature of the curved surface 1a at the tip of the main circuit conductor 1.

  By adopting such a configuration, the potential distribution on the curved surface 2a at the end of the insulation barrier is further coarser than that shown in FIG. 1B as shown in FIG. It can be recognized that the potential difference from the ground metal container 10 is small (the number of equipotential lines is small), and the electric field on the surface of the insulating barrier 2 is lower than that in FIG.

Embodiment 6 FIG.
Next, a sixth embodiment of the present invention will be described with reference to the drawings. 6A and 6B show the configuration of the main circuit conductor and the like in the sixth embodiment. FIG. 6A is a schematic diagram showing the configuration of the main circuit conductor and the insulation barrier, and FIG. 6B shows the potential distribution in the configuration of FIG. FIG.

  In these drawings, the same or corresponding parts as in FIG. The difference from FIG. 4 is that the outer surface of the insulating barrier 2 is composed of a first outer plane 2j extending in the diameter direction of the main circuit conductor 1 and a second outer plane 2k extending in the extending direction of the main circuit conductor 1. The first outer plane 2j and the second outer plane 2k are connected by a curved surface 2l having a curvature smaller than the curvature of the curved surface 1a at the tip of the main circuit conductor 1.

  By adopting such a configuration, the potential distribution on the curved surface 2a at the end of the insulation barrier is further coarser than that shown in FIG. 1B as shown in FIG. When the thickness of the electrode is changed in this way, the potential on the surface of the insulator from the maximum electric field generating portion on the surface of the insulator to the end of the insulating barrier is the extreme value (the minimum value or the maximum value, but the polarity of the applied voltage). Here, it is an extreme value).

  A leading discharge called streamer is generated between the maximum electric field generating portion on the insulating surface and the end of the insulating barrier, before the entire path breakage, from the maximum electric field generating portion on the insulating barrier surface to the end of the insulating barrier. There is a case.

  The streamer tip has a positive or negative polarity.When the polarity of the main circuit conductor to which high voltage is applied is positive, the tip of the streamer has a negative polarity, and when the polarity of the main circuit conductor is negative. Shows a streamer with positive polarity at the tip.

  Positive streamers tend to progress from high potential sites to low sites, and negative streamers tend to progress from low potential sites to high sites. On the contrary, the positive streamer has a property that it is difficult to progress from a site having a low potential to a high site, and the negative streamer is difficult to progress from a site having a high potential to a low site.

  Therefore, when the above-mentioned extreme value is generated in the potential change of the insulator surface, a change in potential that makes it difficult for the streamer to progress in either case of positive or negative appears in the interval from the maximum electric field generating portion to the portion having the extreme value. . As a result, the progress of the streamer is delayed in this section, and the dielectric breakdown voltage increases accordingly.

Embodiment 7 FIG.
Next, a seventh embodiment of the present invention will be described. In this embodiment, in each of the embodiments described above, the insulating barrier 2 is made of an insulating material having a relative dielectric constant of 3 or less, such as Teflon (registered trademark) (relative dielectric constant: 2.1), polycarbonate (relative dielectric constant: 2.9), or the like. It consists of.

  When the insulating barrier 2 is made of this kind of insulating material, the potential distribution on the curved surface 2a at the end of the insulating barrier 2 becomes further coarser than that in FIG. 1B as shown in FIG. Can be recognized to be even lower.

Embodiment 8 FIG.
Next, an eighth embodiment of the present invention will be described with reference to the drawings. FIG. 8 is a schematic diagram showing the configuration of the main circuit conductor and the like in the eighth embodiment. In this figure, the same or corresponding parts as in FIG.

  1A differs from FIG. 1A in that a first recess 1d is formed at the center of the front end of the main circuit conductor 1 and its peripheral surface and the curved surface 1a are connected to each other at the bottom of the first recess 1d. A second recess 1f having a diameter smaller than that of the first recess is formed, a female screw is formed on the peripheral surface of the second recess 1f to form a coupling portion, and a male screw is formed at the center of the inner surface of the insulating barrier 2 2m is formed, and the main circuit conductor 1 and the insulation barrier 2 are coupled to each other by screwing into the female screw of the second recess 1f.

  With such a configuration, the insulating barrier 2 can be firmly fixed to the main circuit conductor 1, and the electric field on the curved surface 2a at the end of the insulating barrier 2 can be relaxed in the same manner as in the above-described embodiments. .

Embodiment 9 FIG.
Next, a ninth embodiment of the present invention will be described with reference to the drawings. FIG. 9 is a schematic diagram showing the configuration of the main circuit conductor and the like in the ninth embodiment. In this figure, the same or corresponding parts as in FIG.

  8 differs from FIG. 8 in that a hole 1g having a diameter smaller than that of the second recess 1f is formed in the bottom surface of the second recess 1f, and a male screw 2n that protrudes toward the inner surface of the insulation barrier 2 at the center of the insulation barrier 2. Further, a hole 2p having a diameter larger than that of the hole 1g is formed in the central portion of the male screw 2n, and a curved surface 2q is formed between the hole 2p and the outer surface of the insulating barrier 2.

  With such a configuration, it is possible to firmly fix the insulating barrier 2 to the main circuit conductor 1, suppress the generation of a high electric field in the screw fixing portion, and improve the withstand voltage performance.

1 main circuit conductor, 1a curved surface, 1d first recess, 1f second recess,
1g hole, 2 insulation barrier, 2a, 2c, 2e curved surface,
2b, 2d protrusion, 2f first inner plane, 2g second inner plane,
2h, 2l curved surface, 2j first outer plane, 2k second outer plane,
2m, 2n male thread, 2p hole, 2q curved surface, 10 ground metal container.

Claims (8)

  A main circuit conductor that is disposed in an insulating gas sealed in a grounded metal container and has a curved surface at the tip, and an insulating barrier that covers the entire curved surface by forming a gap between the main circuit conductor And a curved surface having a curvature of 1/2 or less of the thickness of the insulating barrier is formed at the end of the insulating barrier.   2. The switch according to claim 1, wherein the main circuit conductor has an outer diameter of a portion of the conductor not covered with the insulating barrier smaller than an outer diameter of the portion of the conductor covered with the insulating barrier. gear.   The insulation barrier has a first inner plane extending in the diameter direction of the main circuit conductor and a second inner plane extending in the extension direction of the main circuit conductor, and the first inner plane of the insulation barrier; The switchgear according to claim 1 or 2, wherein the second inner plane is coupled to a curved surface having a smaller curvature than the curved surface of the main circuit conductor.   The insulation barrier has a first outer plane extending in a diameter direction of the main circuit conductor and a second outer plane extending in an extension direction of the main circuit conductor, and the first outer plane of the insulation barrier; The switchgear according to claim 1 or 2, wherein the second outer plane is coupled to a curved surface having a smaller curvature than the curved surface of the main circuit conductor.   The switchgear according to any one of claims 1 to 4, wherein the insulating barrier is made of an insulating material having a relative dielectric constant of 3 or less.   6. The switchgear according to claim 5, wherein the insulating material having a relative dielectric constant of 3 or less is Teflon (registered trademark) or polycarbonate.   The main circuit conductor is provided with a coupling portion at the center of the tip portion, the outer surface connected to the coupling portion is curved, and the insulating barrier is coupled to the coupling portion and fixed to the main circuit conductor. The switchgear according to any one of claims 1 to 6.   At the tip of the main circuit conductor, a first recess connected to the curved surface and a bottom surface of the first recess are formed, and have a smaller diameter than the first recess on the inner peripheral surface. A second recess formed with an internal thread, and a hole formed in the bottom surface of the second recess and having a smaller diameter than the second recess in the extending direction of the main circuit conductor. The insulating barrier is provided with a male screw that is screwed with a female screw on the inner peripheral surface of the second recess, and the male circuit screw is screwed with the female screw so as to couple the main circuit conductor and the insulating barrier. The switchgear according to any one of claims 1 to 6, wherein

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