JP4922012B2 - conductor - Google Patents

Description

  The present invention relates to a current-carrying conductor provided in a sealed metal container in a gas insulated switch formed by sealing an insulating gas in a sealed metal container.

  Generally, a gas insulated switch having a coaxial cylindrical structure is employed in the power system. Here, the structure of the gas insulated switch will be specifically described with reference to the cross-sectional view of FIG. That is, a sealed coaxial cylindrical metal container 1 having a ground potential is provided, and the inside of the metal container 1 is filled with an insulating gas 2 at a high pressure.

  In addition, current-carrying contact portions 3a and 3b are fixedly disposed opposite to each other inside the metal container 1, and slide contacts 5a and 5b, which are current-carrying members, are installed in the contact portions 3a and 3b, respectively. ing. Furthermore, a switch conductor 4 is slidably disposed in the contact portions 3a and 3b, and is electrically connected to the contact portions 3a and 3b by slide contacts 5a and 5b. The conductor 4 is composed of a hollow or solid round bar, and is integrally coupled to the operation rod 10 with a bolt or the like. The conductor 4 is made of a single material such as aluminum or copper.

  By the way, in the gas insulated switch configured as described above, Joule heat is generated by an energizing current in an operating state, and thus the temperatures of the contact portions 3a and 3b and the conductor 4 rise. In particular, when the current is large, the heat generation becomes excessive, and the temperature rise allowable value may be exceeded. In order to suppress the temperature rise in the contact portions 3a and 3b and the conductor 4, it is effective to increase the cooling efficiency by increasing the gas volume by increasing the inner diameter of the metal container 1, for example.

  In addition, a technique is known in which the diameters of the contact portions 3a, 3b and the conductor 4 are increased to increase the cross-sectional area effective for energization, and the electrical resistance of the member is reduced to suppress the temperature rise. However, in these conventional techniques, since the diameter of the metal container 1, the contact portions 3a, 3b, or the conductor 4 is inevitably increased, the size of the gas insulated switch is increased, and the viewpoint of promoting the downsizing of the device is promoted. Is not preferable.

  Therefore, as the material for the contact portions 3a, 3b and the conductor 4, a material having excellent conductivity, specifically, copper having a high conductivity is used. However, copper is expensive and heavy in weight. For this reason, not only is the economic burden high, but a large driving force is required when operating the switch. Therefore, there has been a problem that economy and operability are lowered.

  In order to solve this problem, most of the conductor is made of aluminum and only the end of the conductor is a member having a high conductivity (for example, Patent Document 1) or a material having a high conductivity is coated on the surface. A conductor (for example, Patent Document 2) has been proposed. However, the material having a high conductivity in Patent Document 2 is intended to reduce the damage caused by the arc.

According to these Patent Documents 1 and 2, the use of expensive and heavy material is limited to a part of the conductor, thereby reducing the manufacturing cost of the conductor and promoting the weight reduction of the conductor for excellent operation. Sex can be obtained.
Japanese Patent No. 2825341 Japanese Patent Laid-Open No. 7-114863

  However, the techniques described in Patent Documents 1 and 2 have been pointed out as follows. That is, in Patent Document 1 in which only the end portion of the conductor is a member having a high conductivity, the conductor end portion is excellent in the effect of suppressing the temperature rise, but aluminum having low conductivity is used in the middle portion of the aluminum conductor. Therefore, the effect of suppressing the temperature rise is insufficient, and the temperature rise allowable value may be exceeded.

  In Patent Document 2, a material having a high electrical conductivity, specifically, copper is coated and pressure-bonded on the conductor surface, but the thickness of the coated copper layer is often 1 mm or less. Normally, an alternating current is biased toward the outer circumference of the conductor diameter due to the skin effect, but if the copper layer is thin, substantially the majority of the current flows through the aluminum portion below the copper layer. Although it is conceivable to increase the thickness dimension of the coating layer, it is difficult to manufacture a coating layer having a thickness of 1 mm or more, which is not practical because it is difficult and very expensive. That is, it is difficult to effectively suppress the temperature rise due to the generation of Joule heat only by applying a coating layer on the conductor surface. In the first place, since the material having a high conductivity in Patent Document 2 reduces the damage caused by the arc, it is impossible to apply this technique to the suppression of the temperature rise of the conductor.

  The present invention has been made in response to such a conventional situation, and by efficiently arranging a member having high conductivity, it is possible to surely suppress the temperature rise of the conductor, realizing cost reduction and weight reduction. An object of the present invention is to provide a conductor with improved economy and operability.

In order to achieve the above object, according to the present invention, in a conductor for energization provided in a sealed metal container in which an insulating gas is sealed as an insulating medium, the conductor includes a central member disposed in a central portion. And an outer peripheral member disposed so as to cover the outer peripheral portion of the central member , the central member and the outer peripheral member are electrically connected, and between the outer surface of the central member and the inner surface of the outer peripheral member Is formed with a gap portion through which the insulating gas can flow in and out, and a vent hole connecting the gap portion and the internal space of the sealed metal container is penetrated through the central member .

According to the present invention, the current-carrying conductor is composed of the central member and the outer peripheral member, and the insulating gas is allowed to flow from the vent hole to the gap portion, so that the temperature rise can be reliably suppressed, and the cost can be reduced. Light weight can be realized, and excellent economy and operability can be obtained.

  Hereinafter, an example of an embodiment according to the present invention will be specifically described with reference to cross-sectional views of FIGS. The same members as those in the prior art shown in FIG.

(1) First Embodiment [Configuration]
As shown in FIG. 1, the conductor 4 in the first embodiment includes a solid round bar-shaped central member 4a made of aluminum and a pipe-shaped outer peripheral member 4b made of copper. The outer peripheral member 4b is disposed so as to cover the outer peripheral portion of the central member 4a. Here, the thickness dimension of the outer peripheral member 4b is 5 mm.

  Slide contacts 6a and 6b are installed near both ends of the outer peripheral member 4b, and the central member 4a and the outer peripheral member 4b are electrically connected by the slide contacts 6a and 6b. The slide contacts 6a and 6b are current-carrying members in which a plurality of louvers are arranged in a ring shape, and a spring force is generated when the louver part falls between the center member 4a and the outer peripheral member 4b. The spring force contacts the outer peripheral surface of the central member 4a and the inner peripheral surface of the outer peripheral member 4b to energize.

[Function and effect]
In the conductor 4 of the first embodiment as described above, the outer peripheral member 4b is made of copper having a high conductivity. Therefore, when an alternating current is passed, the current is biased toward the outer peripheral side of the conductor 4 due to the skin effect. In addition, the current flows not on the side of the central member 4a made of aluminum but on the side of the outer peripheral member 4b made of copper. Since the outer peripheral member 4b has a high electrical conductivity, the temperature rise of the conductor 4 can be efficiently suppressed.

  Furthermore, the outer peripheral member 4b having a high conductivity is not a member that is covered and pressure-bonded to the surface of the conductor 4, and is an independent pipe-like member. In addition, the thickness of the outer peripheral member 4b can be freely set according to the current amount of the outer peripheral member 4b, and the outer peripheral member 4b having an optimum thickness sufficient to produce a temperature rise inhibiting effect can be manufactured accurately and easily.

  When copper is used as the material of the conductor 4, the conductivity is high, but there is a demerit that it is heavy and expensive. However, in the conductor 4 of this embodiment, only the pipe-shaped outer peripheral member 4b is made of copper. Compared to the case where the entire 4 is made of copper, it is much lighter and cheaper. Accordingly, the driving force during the operation of the switch is small, excellent operability can be obtained, and the manufacturing cost is also reduced, which is very advantageous economically.

  According to such 1st Embodiment, compared with the single conductor comprised only by the material of the center member 4a, the conductor 4 for electricity supply can suppress a temperature rise by having the outer peripheral member 4b. In addition, since the amount of expensive copper used is limited as compared with a single conductor composed only of the outer peripheral member 4b, there is an effect that operability and economy are improved.

(2) Second Embodiment [Configuration]
As shown in FIG. 2, in the second embodiment, vent holes 7a, 7b, 7c, 7d are provided in the central member 4a. Among them, the ventilation holes 7a and 7b are formed to extend in the radial direction of the central member 4a, and the ventilation holes 7c and 7d are formed to extend in the axial direction of the central member 4a.

  A ventilation hole 7e is formed along the axial direction of the operation rod 10, and the ventilation hole 7e communicates with the ventilation hole 7d on the central member 4a side. A small gap is formed between the outer peripheral surface of the central member 4a and the inner peripheral surface of the outer peripheral member 4b to form a void portion 11. The gap 11 is spatially connected to the inside of the metal container 1 through the plurality of ventilation holes 7a to 7e, and the insulating gas 2 in the metal container 1 flows in and out.

[Function and effect]
According to the second embodiment configured as described above, in addition to the first embodiment, there are the following unique operational effects. That is, when the temperature of the central member 4a and the outer peripheral member 4b of the conductor 4 rises due to the energizing current in the state where the insulating gas 2 flows into the gap 11, the gap 11 is in contact with the central member 4a and the outer member 4b. The temperature of the insulating gas 2 rises and naturally convects through the ventilation holes 7a to 7e. As a result, the insulating gas 2 having a low temperature in the metal container 1 flows into the gap 11 (illustrated by a dotted line). As the low-temperature insulating gas 2 flows into the gap 11, the central member 4a and the outer peripheral member 4b are cooled. Therefore, the temperature rise of the conductor 4 during energization can be suppressed.

  In the above second embodiment, as in the first embodiment, if the outer peripheral member 4b is made of copper, the effect of suppressing the temperature rise of the conductor 4 becomes more remarkable, and the diameter dimension of the conductor 4 is made thinner. Is possible. For this reason, cost reduction and weight reduction can be promoted.

  In the second embodiment, even if both the central member 4a and the outer peripheral member 4b are made of an aluminum material, natural convection of the insulating gas 2 is performed through the ventilation holes 7a to 7e. The cooling effect of the conductor 4 by flowing into the gap portion 11 is obtained. Therefore, even if the central member 4a and the outer peripheral member 4b are made of the same material, the effect of suppressing the temperature rise of the conductor 4 can be expected, and there is no fear of exceeding the allowable temperature rise value.

(3) Third Embodiment [Configuration]
As shown in FIG. 3, in the third embodiment, the conductor 4 composed of the central member 4a and the outer peripheral member 4b is not slidable with respect to the conductors 8a and 8b having a larger outer diameter than the conductor 4, It is fixed and connected by bolt fastening or the like.

  The central member 4a is a cylindrical member, and a ventilation hole 7f is formed in the hollow portion. Further, the conductors 8a and 8b are formed with vent holes 7g and 7h communicating with the vent hole 7f on the central member 4a side. That is, in the conductor 4 of the third embodiment, the gap portion 11 and the internal space of the metal container 1 are connected through the vent holes 7a, 7b, and 7f to 7h, and the gap portion 11 is connected to the inside of the metal vessel 1. The insulating gas 2 is configured to flow in and out.

[Function and effect]
In such a third embodiment, a material having a high conductivity such as copper is applied to the outer peripheral member 4b to obtain an effect of suppressing the temperature rise, and at the same time, the ventilation holes 7a, 7b, 7f to 7h are formed. As a result, the cooling effect by the inflow of the low-temperature insulating gas 2 into the gap 11 is ensured. For this reason, even if the conductor 4 is a thin member sandwiched between the large diameter conductors 8a and 8b and fastened with bolts or the like, the temperature rise allowable value is not exceeded and high reliability is achieved. Can be earned. Therefore, it can be said that the conductor 4 is suitable for a detachable conductor whose diameter is structurally thin.

(4) Fourth Embodiment [Configuration]
As shown in FIG. 5, in the fourth embodiment, the center member 4a and the outer peripheral member 4b are made of materials having different linear expansion coefficients, and are electrically connected by tight fitting due to the difference between the two linear expansion coefficients. There are structural features in this point. More specifically, regarding the linear expansion coefficient of the material, there are a case where the outer peripheral member 4b is larger than the central member 4a and a case where the outer peripheral member 4b is smaller than the central member 4a. The temperature change at is the opposite.

  That is, if the coefficient of linear expansion of the outer peripheral member 4b is larger than that of the central member 4a, the outer peripheral member 4b is disposed outside the central member 4a at a temperature higher than the operating temperature, and the temperature is lowered to achieve a tight fit. And the outer peripheral member 4b are electrically connected. Further, if the linear expansion coefficient of the outer peripheral member 4b is smaller than that of the central member 4a, the outer peripheral member 4b is disposed outside the central member 4a at a temperature lower than the operating temperature, and the temperature is raised to make a tight fit, thereby the central member 4a. And the outer peripheral member 4b are electrically connected.

  Further, a ring-shaped elastic body 9 is disposed between the end of the outer peripheral member 4 b and the operation rod 10. The elastic body 9 is an absorbing member for absorbing a difference in size due to a difference in linear expansion coefficient between the central member 4a and the outer peripheral member 4b.

[Function and effect]
According to the fourth embodiment having the above-described configuration, the center member 4a and the outer peripheral member 4b can be electrically connected without using the slide contacts 5a and 5b, and the parts corresponding to the slide contacts 5a and 5b are unnecessary. The number of points can be reduced. Therefore, in addition to the operational effects of the first embodiment, there can be obtained a merit that the manufacturing cost is further reduced.

  Further, according to the fourth embodiment, when the temperature changes, the central member 4a and the outer peripheral member 4b expand and contract according to the respective linear expansion coefficients, and the length dimension of the conductor 4 changes. The dimensional difference can be absorbed by the elastic body 9. Therefore, in the configuration in which the center member 4a and the outer peripheral member 4b are combined, there is no backlash and a strong structure can be obtained.

(5) Other Embodiments The conductor of the present invention is not limited to the above-described embodiment, and the dimensions, shapes, and the like of each member can be appropriately changed. The present invention can also be applied to a configuration in which a contact is inserted and the other end of the conductor is a free end.

Sectional drawing of 1st Embodiment which concerns on this invention. Sectional drawing of 2nd Embodiment which concerns on this invention. Sectional drawing of 3rd Embodiment which concerns on this invention. Sectional drawing of 4th Embodiment which concerns on this invention. Sectional drawing of 5th Embodiment which concerns on this invention. Sectional drawing of the conventional gas insulation switch.

DESCRIPTION OF SYMBOLS 1 ... Metal container 2 ... Insulating gas 3a, 3b ... Contact part 4, 8a, 8b ... Conductor 4a ... Center member 4b ... Outer peripheral member 5a, 5b, 6a, 6b ... Slide contact 7a-7h ... Vent hole 9 ... Elastic body 10 ... Operating rod 11 ... Cavity

Claims (6)

In the conductor for energization provided in a sealed metal container filled with an insulating gas as an insulating medium,
The conductor is composed of a central member disposed at a central portion and an outer peripheral member disposed so as to cover an outer peripheral portion of the central member,
The central member and the outer peripheral member are electrically connected,
A gap is formed between the outer surface of the central member and the inner surface of the outer peripheral member so that the insulating gas can flow in and out.
A conductor characterized in that a vent hole connecting the gap and the internal space of the sealed metal container is penetrated through the central member .   The conductor according to claim 1, wherein the central member is made of aluminum, and the outer peripheral member is made of copper. The conductor according to claim 1 , wherein the central member and the outer peripheral member are made of the same material. The conductor according to any one of claims 1 to 3 , wherein the central member and the outer peripheral member are electrically connected by an energizing member having a spring portion. It said central member and said peripheral member is made of materials having different linear expansion coefficients, one of the claims 1-3, characterized in that it is electrically connected by an interference fit caused by the difference in linear expansion coefficients of both members The conductor according to claim 1. The conductor according to claim 5 , wherein an absorbing member that absorbs a dimensional difference due to a difference in linear expansion coefficient between both members is disposed between the central member and the outer peripheral member made of materials having different linear expansion coefficients. .

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