JP2011238794A - Insulating barrier and method of manufacturing in-oil shield device using the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To facilitate manufacturing of an in-oil shield device.SOLUTION: An in-oil shield device has two barrier members 5A having the same shape. Each barrier member 5A has an arcuate shape having a center angle larger than 180° with respect to a center axis in cross-section. The barrier members 5A are assembled so that the outer peripheral surfaces of both the end portions 15A, 15B in a circumferential direction of one barrier member 5A are brought into contact with the inner peripheral surfaces of both the end portions 15B, 15A in the circumferential direction of the other barrier member 5A at the corresponding positions in an axial direction of the center axis, and cylindrically disposed so as to surround an in-oil shield 4.

Description

  The present invention relates to an insulation barrier used at a connecting portion between a lead wire and a bushing in a high-voltage oil-filled electrical device, and a method for manufacturing an oil-in-sea shield device including the same.

  In high-voltage oil-filled electrical equipment, a shield in oil for relaxing an electric field is attached to a connection portion between a high-voltage lead wire and a bushing. The oil-in-shield is formed by insulatingly covering a substantially cylindrical conductive core bar that has been narrowed at both ends. In particular, when the voltage is high, the insulation of the oil-in-shield apparatus is improved by surrounding the oil-in-shield shield with an insulation barrier. Patent Documents 1 to 3 are prior art documents disclosing a shielded-in-oil device provided with an insulating barrier.

  In the transformer described in Patent Document 1, the oil shield is supported via a spacer disposed inside the insulating barrier. In the bushing shield device described in Patent Document 2, an insulating barrier divided into two on the bushing side and the opposite side of the bushing side is arranged around the oil shield. In the oil-lead barrier device described in Patent Document 3, an insulating barrier is disposed outside a spacer that is divided in the radial direction and has a fitting structure.

Japanese Patent Publication No.59-23452 JP-A-6-69047 JP 58-28813 A

  In general, an in-oil shield device is manufactured through the following steps. First, the oil shield is assembled so that the conductive core metal of the oil shield and the bushing lower conductor are connected at the lower part of the bushing. Thereafter, the lead wire is connected to the conductive core metal of the shield in oil. Next, an insulating barrier is assembled around the shield in oil. Specifically, after arranging the insulating barrier divided into two or more so as to surround the periphery of the shield in oil, the divided insulating barriers are bonded to each other, or tape is wound around the outer side of the divided insulating barrier. Turn and assemble as one.

  When assembling the insulation barrier in this way, the divided insulation barrier cannot maintain a certain shape until it is glued or wound with tape. Therefore, while maintaining the state where the divided insulating barriers are temporarily assembled into a desired shape, the divided insulating barriers must be fixed together by bonding or wrapping tape. It was complicated.

  The present invention has been made in view of the above-described problems, and provides an insulating barrier and a method for manufacturing an oil-in-shield device including the same, which can simplify the manufacture of the oil-in-shield device. Objective.

  The insulation barrier based on this invention is an insulation barrier used for the oil-filled electrical equipment in which the shield in oil was provided around the connection part of the lead wire and bushing derived | led-out from the coil | winding. The insulating barrier includes two barrier members having the same shape. The barrier member has an arc shape having a central angle larger than 180 ° with respect to the central axis in the cross section. In the insulating barrier, the outer peripheral surfaces of both ends in the circumferential direction of one barrier member are in contact with the inner peripheral surfaces of both ends in the circumferential direction of the other barrier member at positions corresponding to each other in the axial direction of the central axis. By being combined with each other, they are arranged in a cylindrical shape so as to surround the shield in oil.

  According to the present invention, since the assembly of the insulation barrier is facilitated, the manufacture of the in-oil shield device can be simplified.

It is sectional drawing which shows the structure of the shield apparatus in oil which concerns on Embodiment 1 of this invention. It is sectional drawing seen from the II-II line arrow direction of FIG. It is a perspective view which shows the external appearance of the barrier member which comprises the insulation barrier which concerns on the embodiment. It is sectional drawing which shows typically the action force in the lap | wrap part at the time of assembling the insulation barrier which concerns on the embodiment. It is sectional drawing which shows the structure of the shield apparatus in oil which concerns on Embodiment 2 of this invention. It is a perspective view which shows the external appearance of the barrier member which comprises the insulation barrier which concerns on the embodiment. It is a top view which shows typically the action force in the lap | wrap part of the circumferential direction at the time of assembling the insulation barrier which concerns on the embodiment. It is sectional drawing which shows typically the action force in the lap | wrap part of the axial direction at the time of assembling the insulation barrier which concerns on the embodiment. It is sectional drawing which shows the structure of the barrier member and spacer which concern on the embodiment.

  Hereinafter, the manufacturing method of the insulation barrier in Embodiment 1 based on this invention and the shield apparatus in oil provided with the same is demonstrated with reference to figures. In the following description of the embodiments, the same or corresponding parts in the drawings are denoted by the same reference numerals, and the description thereof will not be repeated.

Embodiment 1
FIG. 1 is a cross-sectional view showing a configuration of an oil-in-sea shield device according to Embodiment 1 of the present invention. As shown in FIG. 1, in the oil-in-sea shield device 10 according to Embodiment 1 of the present invention, the lead wire 3 and the bushing 2 led out from the winding are connected. The bushing 2 is made of an insulator such as ceramic. A hollow portion is formed in the bushing 2, and a conductor 7 made of copper or the like is disposed in the hollow portion. The conductor 7 and the lead wire 3 are electrically connected.

  An in-oil shield 4 is disposed around the connecting portion between the lead wire 3 and the bushing 2. The in-oil shield 4 has a cylindrical shape with both end portions curved inward. The in-oil shield 4 is formed by covering a substantially cylindrical conductive metal core 4a with both ends narrowed inward with an insulating material 4b. The conductive metal core 4a is made of a metal such as aluminum, for example.

  An insulating barrier 5 having a cylindrical shape is disposed so as to surround the periphery of the shield 4 in oil. A plurality of spacers 6 having a rectangular parallelepiped shape are disposed on the inner peripheral side surface of the insulating barrier 5 facing the shield 4 in oil. Of the main surfaces of the spacer 6 facing each other, one main surface is in contact with the in-oil shield 4, and the other main surface is in contact with the insulating barrier 5. The insulating barrier 5 and the spacer 6 are formed from a press board.

  The lead wire 3, the bushing 2, the oil-in-sea shield 4, the spacer 6, the insulating barrier 5 and the like are accommodated in the bushing case 1. The bushing case 1 is immersed in the insulating oil 8.

  FIG. 2 is a cross-sectional view as seen from the direction of arrows II-II in FIG. In FIG. 2, for the sake of simplicity, only the insulation barrier, the spacer, and the oil shield are shown. FIG. 3 is a perspective view showing an appearance of the barrier member that constitutes the insulating barrier according to the present embodiment.

  As shown in FIGS. 2 and 3, the insulating barrier 5 according to the present embodiment includes two barrier members 5 </ b> A having the same shape. The barrier member 5 </ b> A has an arc shape having a central angle 14 greater than 180 ° with respect to the central axis 13 in the cross section, and extends in the axial direction of the central axis 13.

  Of the two barrier members 5A, the insulating barrier 5 is such that the outer peripheral surfaces of both end portions 15A, 15B in the circumferential direction of one barrier member 5A are the inner circumferences of both end portions 15B, 15A in the circumferential direction of the other barrier member 5A. By being combined so as to be in contact with each other at positions corresponding to each other in the axial direction of the central shaft 13, they are arranged in a substantially cylindrical shape so as to surround the in-oil shield 4.

  A portion where the outer peripheral surface of the end portion 15B in the circumferential direction of one barrier member 5A is in contact with the inner peripheral surface of the end portion 15A in the circumferential direction of the other barrier member 5A is defined as a lap portion 9A. A portion where the outer peripheral surface of the end portion 15A in the circumferential direction of one barrier member 5A is in contact with the inner peripheral surface of the end portion 15B in the circumferential direction of the other barrier member 5A is defined as a wrap portion 9B.

  FIG. 4 is a cross-sectional view schematically showing the acting force at the lap portion when the insulating barrier according to the present embodiment is assembled. As shown in FIG. 4, when the two barrier members 5A are combined, the lap portions 9A and 9B are restored to the outside by the elastic force of the press board constituting one of the barrier members 5A arranged inside. Force 11 acts. Further, in the wrap portions 9A and 9B, a restoring force 12 that tends to contract inwardly acts by the elastic force of the press board constituting the other barrier member 5A disposed on the outside.

  As described above, the restoring force 11 and the restoring force 12 act on the wrap portions 9A and 9B, but the two barrier members 5A combined are formed in the same shape by the same material, and thus the restoring force 11 And the restoring force 12 are substantially equal. Therefore, the assembled two barrier members 5A are fixed to each other at the wrap portions 9A and 9B to maintain a cylindrical shape.

  In this embodiment, the diameter of the cylinder formed by the insulating barrier 5 after assembly is about 500 mm, and the circumferential length of the wrap portions 9A and 9B is about 50 mm. As a standard of the circumferential length of the wrap portions 9A and 9B, it is preferable that the length is 5% or more and 10% or less of the diameter of the cylinder formed by the insulating barrier 5.

  When the circumferential length of the wrap portions 9A and 9B is 5% or less of the diameter of the cylinder formed by the insulating barrier 5, the barrier members 5A in the wrap portions 9A and 9B are not sufficiently fixed to each other and assembled. The insulating barrier 5 is easily decomposed.

  When the circumferential length of the wrap portions 9A and 9B is 10% or more of the diameter of the cylinder formed by the insulating barrier 5, the end portion 15A in the circumferential direction of one barrier member 5A disposed on the inner side The tip of 15B comes away from the end portions 15B, 15A in the circumferential direction of the other barrier member 5A and approaches the oil shield 4 side. In this case, the cross-sectional shape of the assembled insulating barrier 5 becomes an irregular shape such as an ellipse, which is not preferable in terms of the insulating performance of the insulating barrier 5.

  By providing the insulating barrier 5 having the above-described configuration, the insulation distance can be secured by the spacer 6 and the dielectric strength in the circumferential direction of the in-oil shield 4 can be improved. As a result, the oil shield device 10 can be made compact.

  Hereinafter, a manufacturing method of the oil shield device 10 according to the present embodiment will be described. First, the oil-in-shield 4 is assembled so that the conductive core 4a of the oil-in-shield 4 and the bushing lower conductor are connected at the lower part of the bushing 2. Thereafter, the lead wire 3 is connected to the conductive cored bar 4a of the in-oil shield 4. A conductor 7 is disposed inside the bushing 2, and the conductor 7 and the lead wire 3 are electrically connected. Next, an in-oil shield 4 is disposed around the connecting portion between the lead wire 3 and the bushing 2.

  Thereafter, two barrier members 5A each having a plurality of spacers 6 attached on the inner peripheral side surface are prepared and combined with each other. As a specific combination method, the press board constituting one barrier member 5A disposed on the inner side is formed in a slightly closed shape in the circumferential direction. Moreover, the press board which comprises the other barrier member 5A arrange | positioned outside is made into the shape opened slightly in the circumferential direction. Since the press board has elasticity, the barrier member 5A can be elastically deformed by applying a force.

  After combining one barrier member 5A on the inner peripheral side of the other barrier member 5A, the applied force is removed. Both barrier members 5A try to return to the original shape by the elastic force of the press board. As a result, the barrier members 5A are combined with each other, and the insulating barrier 5 is assembled. The assembled insulation barrier 5 is disposed in a cylindrical shape so as to surround the shield 4 in oil.

  Finally, the bushing case 1 is arranged, and the insulating oil 8 is immersed in the bushing case 1, whereby the oil shield device 10 is assembled. In addition, you may fix the barrier members 5A after an assembly using an adhesive agent or a tape so that the insulation barrier 5 assembled in the cylinder shape may not be disassembled.

  By manufacturing the oil shield device 10 by the above manufacturing method, the insulating barrier 5 can be easily assembled around the oil shield 4. Specifically, the insulating barrier 5 can be maintained in a cylindrical shape only by combining the two barrier members 5A without particularly using an adhesive or a tape. As a result, since the assembly of the insulating barrier 5 becomes easy, the manufacture of the oil shield device 10 can be simplified. Further, in this embodiment, since the insulating barrier 5 is configured by using two identical barrier members 5A, the number of parts to be managed can be reduced.

  Hereinafter, an insulating barrier in Embodiment 2 based on the present invention and a manufacturing method of an oil shield device provided with the same will be described with reference to the drawings.

Embodiment 2
FIG. 5 is a cross-sectional view showing the configuration of the oil-in-sea shield device according to Embodiment 2 of the present invention. As shown in FIG. 5, in the oil-in-sea shield device 20 according to Embodiment 2 of the present invention, the insulating barrier 25 is arranged in a cylindrical shape with both ends narrowed. Since other configurations are the same as those of the first embodiment, description thereof will not be repeated.

  FIG. 6 is a perspective view showing an appearance of a barrier member constituting the insulating barrier according to the present embodiment. FIG. 7 is a top view schematically showing the acting force in the circumferential wrap portion when the insulating barrier according to this embodiment is assembled. FIG. 8 is a cross-sectional view schematically showing the acting force in the axial wrap portion when the insulating barrier according to the present embodiment is assembled.

  As shown in FIGS. 6 to 8, the insulating barrier 25 according to the present embodiment includes two barrier members 25 </ b> A having the same shape. The barrier member 25 </ b> A has an arc shape having a central angle 34 greater than 180 ° with respect to the central axis 33 in the cross section, and extends in the axial direction of the central axis 33. In the barrier member 25 </ b> A, both end portions 22 are curved inward in the axial direction of the central shaft 33.

  Of the two barrier members 25A, the insulating barrier 25 has an outer peripheral surface of both end portions 35A and 35B in the circumferential direction of one barrier member 25A and an inner periphery of both end portions 35B and 35A in the circumferential direction of the other barrier member 25A. The surfaces are combined so as to be in contact with each other at positions corresponding to each other in the axial direction of the central shaft 33.

  A portion where the outer peripheral surface of the end portion 35B in the circumferential direction of one barrier member 25A is in contact with the inner peripheral surface of the end portion 35A in the circumferential direction of the other barrier member 25A is defined as a lap portion 29A. A portion where the outer peripheral surface of the end portion 35A in the circumferential direction of one barrier member 25A is in contact with the inner peripheral surface of the end portion 35B in the circumferential direction of the other barrier member 25A is defined as a lap portion 29B.

  The insulating barrier 25 has an outer peripheral surface of both end portions 36A and 36B in the axial direction of one barrier member 25A, and an inner periphery of both end portions 36B and 36A in the axial direction of the other barrier member 25A. By being combined so as to be in contact with the surface, both ends are arranged in a substantially cylindrical shape so as to surround the shield 4 in oil.

  A portion where the outer peripheral surface of the end portion 36B in the axial direction of the central axis 33 of one barrier member 25A is in contact with the inner peripheral surface of the end portion 36A in the axial direction of the central shaft 33 of the other barrier member 25A is a lap portion 39A. And A portion where the outer peripheral surface of the end portion 36A in the axial direction of the central axis 33 of one barrier member 25A is in contact with the inner peripheral surface of the end portion 36B in the axial direction of the central shaft 33 of the other barrier member 25A is a lap portion 39B. And

  As shown in FIG. 7, when the two barrier members 25A are combined, the wrap portions 29A and 29B tend to spread outward due to the elastic force of the press board constituting one of the barrier members 25A arranged on the inner side. A restoring force 31 acts. In addition, in the wrap portions 29A and 29B, a restoring force 32 that tends to contract inwardly acts by the elastic force of the press board constituting the other barrier member 25A disposed on the outside.

  As described above, the restoring force 31 and the restoring force 32 act on the wrap portions 29A and 29B, but the two barrier members 25A combined are formed of the same material in the same shape, and thus the restoring force 31. And the restoring force 32 are substantially equal. Therefore, the assembled two barrier members 25A are fixed to each other at the wrap portions 29A and 29B and maintain a cylindrical shape.

  As shown in FIG. 8, when the two barrier members 25A are combined, the wrap portions 39A and 39B tend to spread outward due to the elastic force of the press board constituting one of the barrier members 25A arranged inside. A restoring force 41 acts. In addition, in the wrap portions 39A and 39B, a restoring force 42 that tends to contract inwardly acts by the elastic force of the press board constituting the other barrier member 25A disposed on the outside.

  In this way, the restoring force 41 and the restoring force 42 act on the wrap portions 39A and 39B, but the two barrier members 25A combined are formed in the same shape with the same material, and thus the restoring force 41 And the restoring force 42 are substantially equal. Therefore, the assembled two barrier members 25A are fixed to each other at the wrap portions 39A and 39B and maintain a shape in which both ends are narrowed.

  By providing the insulation barrier 25 having the above-described configuration, the insulation distance can be secured by the spacer 26 and the dielectric strength in the circumferential direction of the in-oil shield 4 can be improved. Furthermore, since both ends in the axial direction of the insulating barrier 25 are narrowed, the size of the opening 21 of the insulating barrier 25 shown in FIGS. 5 and 7 can be reduced. As a result, as compared with the oil-in-shield device 10 according to the first embodiment, in the oil-in-shield device 20 according to the present embodiment, the high electric field portion generated in the axial direction of the oil-in-shield 4 is surrounded by the insulating barrier 25. As a result, the dielectric strength can be increased.

  Hereinafter, a manufacturing method of the oil shield device 20 according to the present embodiment will be described. First, the oil-in-shield 4 is assembled so that the conductive core 4a of the oil-in-shield 4 and the bushing lower conductor are connected at the lower part of the bushing 2. Thereafter, the lead wire 3 is connected to the conductive cored bar 4a of the in-oil shield 4. A conductor 7 is disposed inside the bushing 2, and the conductor 7 and the lead wire 3 are electrically connected. Next, an in-oil shield 4 is disposed around the connecting portion between the lead wire 3 and the bushing 2.

  Thereafter, two barrier members 25A each having a plurality of spacers 6 attached on the inner peripheral side surface are prepared and combined with each other. As a specific combination method, the press board constituting one of the barrier members 25A disposed on the inner side is formed in a slightly closed shape in the circumferential direction and the axial direction. Further, the press board constituting the other barrier member 25A disposed on the outside is formed into a shape slightly opened in the circumferential direction and the axial direction. Since the press board has elasticity, the barrier member 25A can be elastically deformed by applying a force.

  After combining one barrier member 25A on the inner peripheral side of the other barrier member 25A, the applied force is removed. Both barrier members 25A try to return to the original shape by the elastic force of the press board. As a result, the barrier members 25A are combined with each other, and the insulating barrier 25 is assembled. The assembled insulation barrier 25 is arranged in a cylindrical shape whose both ends are narrowed so as to surround the oil-in-shield 4.

  Finally, the bushing case 1 is arranged, and the insulating oil 8 is immersed in the bushing case 1, whereby the oil shield device 20 is assembled. The assembled barrier members 25A may be fixed to each other using an adhesive or a tape so that the assembled insulating barrier 25 is not disassembled.

  By manufacturing the in-oil shield device 20 by the above manufacturing method, the insulating barrier 25 can be easily assembled around the in-oil shield 4. Specifically, the insulating barrier 25 can be maintained in a cylindrical shape in which both ends are narrowed only by combining the two barrier members 25A without particularly using an adhesive or a tape. As a result, the assembly of the insulating barrier 25 is facilitated, so that the production of the oil shield device 20 can be simplified. In this embodiment, since the insulating barrier 25 is configured by using two identical barrier members 25A, the number of parts to be managed can be reduced.

  FIG. 9 is a cross-sectional view illustrating the configuration of the barrier member and the spacer according to the present embodiment. As shown in FIG. 9, in the barrier member 25 </ b> A of the present embodiment, a plurality of spacers 26 are attached on the inner peripheral side surface facing the in-oil shield 4. Of the principal surfaces of the spacer 26 facing each other, one principal surface is in contact with the oil-in-shield 4 and the other principal surface is in contact with the insulating barrier 25. The insulating barrier 25 and the spacer 26 are formed from a press board.

  Since both end portions 22 in the axial direction of the central axis 33 of the barrier member 25A are curved toward the inner peripheral side, both end portions 23 in the axial direction of the spacer 26 are also curved toward the inner peripheral side. As shown in FIG. 5, when the insulating barrier 25 is assembled, both end portions 23 of the spacer 26 are arranged so as to hold the shield 4 in oil. Therefore, the position of the assembled insulating barrier 25 is fixed in the axial direction by the spacer 26. Therefore, the assembly of the insulating barrier 25 is further facilitated.

  In addition, the said embodiment disclosed this time is an illustration in all the points, Comprising: It does not become a basis of limited interpretation. Therefore, the technical scope of the present invention is not interpreted only by the above-described embodiments, but is defined based on the description of the scope of claims. Further, all modifications within the meaning and scope equivalent to the scope of the claims are included.

  1 bushing case, 2 bushing, 3 lead wire, 4 oil shield, 4a conductive cored bar, 4b insulating material, 5,25 insulating barrier, 5A, 25A barrier member, 6,26 spacer, 7 conductor, 8 insulating oil, 9A, 9B, 29A, 29B, 39A, 39B Wrap part, 10, 20 Oil shield device, 11, 12, 31, 32, 41, 42 Restoring force, 13, 33 Central axis, 14, 34 Central angle, 15A, 15B, 35A, 35B, 36A, 36B end, 21 opening.

Claims (5)

An insulation barrier used in an oil-filled electrical device in which a shield in oil is provided around a connection portion between a lead wire and a bushing derived from a winding,
Including two barrier members having the same shape;
The barrier member has an arc shape having a central angle larger than 180 ° with respect to the central axis in a cross section,
The outer peripheral surfaces of both ends in the circumferential direction of one of the barrier members are combined so that the outer peripheral surfaces of both ends in the circumferential direction of the other barrier member are in contact with each other at positions corresponding to each other in the axial direction of the central axis. Thus, an insulating barrier arranged in a cylindrical shape so as to surround the shield in oil. The barrier member has both end portions curved inward in the axial direction,
By combining the outer peripheral surfaces of both end portions of the one barrier member in the axial direction so as to be in contact with the inner peripheral surfaces of both end portions of the other barrier member in the axial direction, both ends are narrowed into a cylindrical shape. The insulation barrier of claim 1 disposed.   The insulation barrier according to claim 1 or 2, wherein a spacer for securing an insulation distance is disposed on an inner peripheral side surface of the barrier member facing the shield in oil. Connecting the lead wire and the bushing derived from the winding;
Arranging a shield in oil around the connecting portion between the lead wire and the bushing;
Two barrier members of the same shape having an arc shape having a central angle larger than 180 ° with respect to the central axis in the cross section, the outer peripheral surfaces of both end portions in the circumferential direction of one of the barrier members are circles of the other barrier member A step of arranging the insulating barrier in a cylindrical shape so as to surround the shield in oil by combining the inner peripheral surfaces of both end portions in the circumferential direction so as to be in contact with each other at positions corresponding to each other in the axial direction of the central axis; A method for manufacturing an in-oil shield device.   In the step of disposing the insulation barrier, the barrier member whose both ends in the axial direction are curved toward the inner peripheral side, the outer peripheral surface of both ends in the axial direction of one of the barrier members is the one of the barrier member of the other The method for manufacturing an in-oil shield device according to claim 4, wherein the insulating barrier is arranged in a cylindrical shape in which both ends are narrowed by being combined so as to be in contact with inner peripheral surfaces of both ends in the axial direction.

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