JP5169386B2 - Attaching and removing method of grounding adapter and charging cable using grounding adapter - Google Patents

Description

  The present invention relates to a grounding adapter capable of safely attaching and detaching a power-applying cable, and a method for attaching and removing a power-applying cable using the grounding adapter.

  In order to connect a sealed high voltage device such as a GIS (gas insulated switchgear) and a power cable (hereinafter referred to as a power supply cable) that feeds power to the high voltage device, A bushing that penetrates the wall surface is used.

  In addition, a bushing having an internal disconnect function for performing a power application test on a power feeding cable connected to the bushing is used (for example, see Patent Document 1).

  As shown in FIG. 2, the bushing described in Patent Document 1 has a branched shape, and is airtightly attached to the lower wall surface 20 of the high-voltage device. The bushing 10 is provided with a power supply cable connection port 12 downward and a power application cable connection port 13 obliquely downward.

  The bushing 10 is a molded body in which the bushing main body 11 is made of an insulator such as an epoxy resin, and an internal electrode (device-side internal electrode 14) that is electrically connected to an internal device of a high-voltage device therein. And an internal electrode (cable side internal electrode 15) to which the power supply cable 30 and the power application cable 40 (see FIG. 6) are connected.

  The device-side internal electrode 14 and the cable-side internal electrode 15 are electrically connected via a connection conductor 50. The connection conductor 50 can be inserted / removed through the connection port 13 of the cable for power application.

  In a normal operation (use) state, a power feeding cable 30 from a cable line is connected to the connection port 12 of the power feeding cable, and the connection conductor 50 is inserted into the connection port 13 of the power transmission cable. Sealed with an insulating plug 60.

  On the other hand, when a voltage application test is performed by applying a high voltage to the power supply cable 30, the terminal of the power supply cable 40 is attached to the connection port 13 of the power supply cable. In this case, the connection conductor 50 and the insulating plug 60 are removed from the connection port 13 of the power-applying cable, and a disconnection insulating spacer 80 (see FIG. 4) having the same shape as the connection conductor 50 is used instead of the connection conductor 50. The device-side internal electrode 14 and the cable-side internal electrode 15 are electrically separated from each other.

  The device-side internal electrode 14, the cable-side internal electrode 15, the connection conductor 50, and the disconnection insulating spacer 80 constitute a disconnection function part of the bushing 10.

In such a bushing 10, an operation tool in which a tightening shaft and a drawing shaft are arranged coaxially as described in Patent Document 2 and Patent Document 3 as a tool for inserting and removing the connection conductor 50 and the disconnecting insulating spacer 80. Is used.
JP-A-9-84245 Japanese Patent Laid-Open No. 5-325687 JP-A-8-33147

  As described above, it is necessary to replace the connecting conductor and the insulating spacer for disconnection before and after the power application test on the power supply cable. There may be safety issues with the internal electrodes. The safety issue arises when the power supply cable connected to the cable side internal electrode is laid next to another live cable and the live cable This is because a high voltage may be induced in the cable-side internal electrode due to mutual induction.

  On the other hand, although the operation tool described in Patent Document 3 includes a ground electrode and a lead wire connected to the ground electrode, the cable-side internal electrode is always replaced during the replacement work between the connection conductor and the insulating spacer for disconnection. It does not enable grounding. This is because the adjacent cable was not in a live state at the time of plugging / unplugging work at that time, and there was no safety problem, so there was no request for constant grounding.

  Therefore, an object of the present invention is to provide a grounding adapter and a grounding adapter that enable grounding of the cable-side internal electrode at all times during a predetermined work in attaching and detaching a power-applying cable, and enabling safe work. An object is to provide a method for attaching and removing a power-applying cable.

  In order to achieve the above-described object, the present invention provides a cable-side inner portion that is detachably fixed to the bushing and constitutes the disconnecting function part when the connecting conductor and the insulating spacer for disconnecting that constitute the disconnecting function part of the bushing are replaced. A grounding adapter for grounding an electrode, wherein the connecting conductor and the disconnecting insulating spacer have a hollow that can be inserted and removed, and are inserted into a power connection cable connection port of the bushing, the tip of which is connected to the cable side Provided is a grounding adapter comprising a cylindrical portion that is in electrical contact with an internal electrode.

  Further, in order to achieve the above object, the present invention inserts the grounding adapter of the present invention into the power-applying cable connection port of the bushing, removably fixes the bushing, and attaches the tip portion to the cable. A step of removing the connection conductor, attaching the disconnecting insulating spacer to the position where the connection conductor was attached, and then removing the grounding adapter; Provided is a method for attaching a power-applying cable to a bushing.

Further, in order to achieve the above object, the present invention inserts the grounding adapter of the present invention into the power-applying cable connection port of the bushing, removably fixes the bushing, and attaches the tip portion to the cable. after taking the ground by electrical contact with the side internal electrodes, remove the insulating spacer for the disconnector, installed in a position before Kidanro insulating spacer is attached to the connection conductor, then the grounding adapter There is provided a method of removing a power-applying cable from a bushing, comprising a step of removing.

  According to the present invention, the grounding adapter and the grounding adapter that enable the grounding of the cable side internal electrode and perform the work safely at all times during the predetermined work in the installation and the removal work of the power cable are used. It is possible to provide a method for attaching and detaching a power cable.

  FIG. 1A is a diagram showing an outline of a procedure for attaching a power-applying cable, and FIG. 1B is a diagram showing an outline of a procedure for removing an electric-applying cable. 2 is a longitudinal sectional view showing the state of the bushing during normal operation, FIG. 3 is a longitudinal sectional view showing the state of the bushing when the grounding adapter is mounted, and FIG. 5 is a longitudinal sectional view showing the state of the bushing, FIG. 5 is a longitudinal sectional view showing the state of the bushing when the grounding jig is installed at the time of cleaning, and FIG. 6 is a state of the bushing when the power cable is attached. It is a longitudinal cross-sectional view shown.

  Based on FIGS. 1-6, the attachment method and removal method of the cable for a power transmission which concern on embodiment of this invention are demonstrated below.

[How to attach the cable for charging]
As shown in FIG. 1 (a), the installation work of the power cable to the bushing is as follows: (A) Insulation plug removal process → (B) Grounding adapter installation process → (C) Connection conductor removal process And the step of attaching the insulating spacer for disconnection → (D) The step of attaching the grounding jig at the time of cleaning and the step of cleaning the cable connection port for electricity application → (E) The step of attaching the cable for electricity application. Each step will be described in order below.

(A) Insulation plug removal process As shown in FIG. 2, a bushing 10 having a branch shape is airtightly attached to a lower wall surface 20 of a sealed high voltage device such as a GIS (gas insulated switchgear). Yes. The structure of the bushing 10 is the same as that described in FIG. A power supply cable 30 is connected to the bushing 10 from below. The device-side internal electrode 14 and the cable-side internal electrode (internal shielding metal fitting) 15 are electrically connected via a connection conductor 50. Further, an insulating plug 60 is attached to the cable connection port 13 for charging which opens obliquely downward to the right.

  When attaching the cable for charging, first, the insulating plug 60 is removed from the cable connection port 13 for charging.

(B) Grounding Adapter Installation Step After removing the insulating plug 60 from the power-applying cable connection port 13, instead of grounding, as shown in FIG. The adapter 1 is installed.

  In the grounding adapter 1, the cylindrical portion 101 is inserted into the power-applying cable connection port 13, and the tip thereof is in electrical contact with the inner surface of the receiving port provided in the cable-side internal electrode (internal shielding metal fitting) 15. doing. Further, the bush 102 is screwed to the bushing main body 11 with a screw 103 at a portion of the flange 102 provided at the rear end, and is grounded by a ground lead wire 104.

(C) Connection conductor removal step and disconnection insulating spacer attachment step A rod-shaped operating tool 70 having the same structure as that described in Patent Document 2 is inserted through the cylindrical hollow portion of the grounding adapter 1, and the rod-shaped operating tool 70 is inserted. The connection conductor 50 is fitted into the connection conductor 50, and the connection conductor 50 is pulled out through the cylindrical hollow portion of the grounding adapter 1 and removed.

  Next, as shown in FIG. 4, with the disconnection insulating spacer 80 fitted to the rod-shaped operation tool 70, the hollow adapter is inserted through the hollow of the cylindrical portion of the grounding adapter 1, and the disconnection is performed at the position where the connection conductor 50 is attached. An insulating spacer 80 is attached. After the attachment, the fitting with the insulating spacer 80 for disconnection is released, and the rod-shaped operating tool 70 is pulled out.

  During these operations, the cable-side internal electrode (internal shielding metal fitting) 15 is grounded via the grounding adapter 1, so that the safety of the operation is maintained.

(D) Step of attaching grounding jig for cleaning and cleaning step of cable connection port for charging After pulling out the rod-like operation tool 70, the grounding adapter 1 is removed from the cable connection port 13 for charging, as shown in FIG. Alternatively, a cleaning rod-shaped grounding jig 2 having a cup-shaped portion 201 at the tip is attached.

  The outer peripheral surface of the cup-shaped portion 201 at the tip is in electrical contact with the inner surface of the receiving port provided in the cable side internal electrode (internal shielding metal fitting) 15. In addition, a ground lead wire 203 is attached to the rear end of the small-diameter bar-shaped portion 202 to be grounded.

  In this state, a cleaning operation is performed to remove foreign matters and dirt from the external interface 17 of the power cable connection port 13 before attaching the terminal of the power cable 40.

  During the cleaning operation, the cable side internal electrode (internal shielding metal fitting) 15 is grounded via the grounding jig 2 at the time of cleaning, and the safety of the operation is maintained.

(E) Installation process of power-applying cable After cleaning work, the grounding jig 2 for cleaning is removed from the power-applying cable connection port 13 and a power-applying cable (lead cable) 40 is attached as shown in FIG.

[How to remove the power cable]
As shown in FIG. 1 (b), the work of removing the power cable from the bushing is as follows: (F) Power cable removal process → (G) Ground adapter installation process → (H) Insulation spacer for disconnection Removal process and connection conductor installation process → (I) Cleaning grounding jig installation process and power application cable connection port cleaning process → (J) Insulation plug installation process. Each step will be described in order below.

(F) Step of removing power-carrying cable When removing the power-cable cable, first, the power-cable cable 40 is removed from the power-cable cable connection port 13.

(G) Attaching process of grounding adapter After the powering cable 40 is removed from the powering cable connection port 13, the grounding adapter 1 provided with the flange 102 at one end of the cylindrical portion 101 is attached instead. To do.

  In the grounding adapter 1, the cylindrical portion 101 is inserted into the power-applying cable connection port 13, and the tip thereof is in electrical contact with the inner surface of the receiving port provided in the cable-side internal electrode (internal shielding metal fitting) 15. doing. Further, the bush 102 is screwed to the bushing main body 11 with a screw 103 at a portion of the flange 102 provided at the rear end, and is grounded by a ground lead wire 104.

(H) Removal step of insulating spacer for disconnection and attachment step of connecting conductor A rod-like operation tool 70 having the same structure as that described in Patent Document 2 is inserted through the cylindrical hollow portion of the grounding adapter 1, and the rod-like operation tool 70 is inserted. The end of the switch is fitted into the disconnecting insulating spacer 80, and the disconnecting insulating spacer 80 is pulled out through the cylindrical hollow portion of the grounding adapter 1 and removed.

  Next, in a state where the connection conductor 50 is fitted to the rod-shaped operation tool 70, the connection conductor 50 is inserted through the hollow cylindrical portion of the grounding adapter 1 and the connection conductor 50 is attached to the position where the disconnection insulating spacer 80 is attached. After the attachment, the fitting with the connection conductor 50 is released, and the rod-shaped operating tool 70 is pulled out.

  During these operations, the cable-side internal electrode (internal shielding metal fitting) 15 is grounded via the grounding adapter 1, so that the safety of the operation is maintained.

(I) Cleaning process of attaching grounding jig and cleaning process of charging cable connection port After pulling out the rod-shaped operating tool 70, the grounding adapter 1 is removed from the charging cable connection port 13, and a cup is attached to the tip instead. A small-diameter bar-shaped grounding jig 2 having a shape portion 201 is mounted.

  The outer peripheral surface of the cup-shaped portion 201 at the tip is in electrical contact with the inner surface of the receiving port provided in the cable side internal electrode (internal shielding metal fitting) 15. In addition, a ground lead wire 203 is attached to the rear end of the small-diameter bar-shaped portion 202 to be grounded.

  In this state, before attaching the insulating plug 60, a cleaning operation is performed to remove foreign substances from the external interface 17 of the power-applying cable connection port 13.

  During the cleaning operation, the cable side internal electrode (internal shielding metal fitting) 15 is grounded via the grounding jig 2 at the time of cleaning, and the safety of the operation is maintained.

(J) Insulation plug installation step After cleaning work, the grounding jig 2 for cleaning is removed from the cable connection port 13 for charging, and the insulation plug 60 is installed as shown in FIG.

[Grounding adapter]
FIG. 7 is a perspective view of the grounding adapter according to the embodiment of the present invention.
The grounding adapter 1 is inserted into the power-applying cable connection port 13 of the bushing 10 and has a cylindrical portion 101 whose tip is electrically in contact with the cable-side internal electrode 15 and a rear end portion of the cylindrical portion 101. And a provided ridge 102. The flange 102 is provided with a screw hole 102a for fixing the flange 102 to the entrance portion of the power-applying cable connection port 13 with a screw and a ground wire connection hole 102b for connecting a ground wire. A grounding lead wire is connected to the grounding wire connection hole 102b (if there are a plurality of them) to perform grounding.

  As a material for the grounding adapter 1, any conductive material can be suitably used.

  The inner diameter of the cylindrical portion 101 must be equal to or larger than the largest outer diameter of these so that the connection conductor 50, the disconnecting insulating spacer 80, and the rod-shaped operation tool 70 can be inserted and removed. Further, the outer diameter of the cylindrical portion 101 is large enough to be inserted into the power-applying cable connection port 13, and the distal end portion of the inserted cylindrical portion 101 is an outer diameter that can be in electrical contact with the cable-side internal electrode 15. Need to be in shape.

[Grounding jig for cleaning]
FIG. 8 is a perspective view of the grounding jig for cleaning according to the embodiment of the present invention.
The cleaning grounding jig 2 is inserted into the power-applying cable connection port 13 of the bushing 10 and electrically contacts the cable-side internal electrode 15, and a thin part having the cup-shaped portion 201 at the tip thereof. And a rod-shaped portion 202 having a diameter. Grounding is performed by connecting a grounding lead wire to the rear end of the thin rod portion 202.

  As a material of the cleaning earthing jig 2, any conductive material can be preferably used.

  The cup-shaped portion 201 has an outer diameter large enough to be inserted into the power-applying cable connection port 13 and needs to have an outer diameter and a shape that can be electrically contacted with the cable-side inner electrode 15. The cup-shaped portion 201 is fitted between the cable-side internal electrode 15 and the disconnecting insulating spacer 80 (or the connecting conductor 50), as shown in FIG. 5, in order to ensure the safety of grounding at all times. It is desirable that Moreover, it is desirable that the height does not become an obstacle to cleaning of the external interface 17, specifically, about 1 cm to 4 cm.

  It is desirable that the thin rod-like portion 202 has a thickness that does not hinder the cleaning of the external interface 17, specifically, an outer diameter of about 0.8 cm to 2.0 cm. The length is preferably about 20 cm to 40 cm.

[Effect of the embodiment of the present invention]
According to the embodiment of the present invention, during the predetermined work (especially, the replacement work of the connection conductor and disconnection insulating spacer and the cleaning work of the external interface) during the installation and removal work of the power-applying cable, the cable side inside The electrode can be grounded and work can be performed safely.

Further, according to the grounding adapter of the embodiment of the present invention, the following effects can be obtained.
(1) The grounding adapter 1 is fixed to the bushing body 11 by fixing the collar 102 to the entrance portion of the power-applying cable connection port 13, so that the grounding adapter 1 moves during the operation and the cable side Since the cable-side internal electrode is always grounded without being brought into contact with the internal electrode 15, the replacement work of the connection conductor and the disconnecting insulating spacer can be performed safely.
(2) Unlike the case of grounding via the rod-like operation tool 70 as in Patent Document 3, since the ground is always grounded, the internal interface 16 is cleaned before the connection conductor or the disconnecting insulating spacer is mounted. It can be done safely.
(3) Since it is not necessary to use the rod-like operation tool 70 to which the ground wire is connected as in Patent Document 3, the work can be performed smoothly.
(4) Since the cylindrical portion 101 of the grounding adapter 1 serves as a guide path for the replacement work of the connection conductor and disconnection insulating spacer, which has been performed slowly and carefully so far as not damaging the external interface 17, Since the work can be performed smoothly and the cylindrical portion 101 serves as a protective wall, there is no fear of damaging the external interface 17.

[Other Embodiments]
The present invention is not limited to the embodiment described above, and various modifications can be made without departing from the scope of the invention. For example, the cup-shaped portion 201 may be a cylindrical portion. Moreover, although the bushing described in FIG. 1 of Patent Document 1 has been described as an example, the present invention can be similarly applied to the bushing (T-type) described in FIG.

(A) is a figure which shows the outline of the attachment work procedure of an electric power cable, (b) is a figure which shows the outline of the removal work procedure of an electric power cable. It is a longitudinal cross-sectional view which shows the state of the bushing at the time of normal driving | operation. It is a longitudinal cross-sectional view which shows the state of the bushing at the time of earthing | grounding adapter mounting | wearing. It is a longitudinal cross-sectional view which shows the state of the bushing at the time of connection member replacement | exchange. It is a longitudinal cross-sectional view which shows the state of a bushing at the time of cleaning earth | ground jig | tool mounting | wearing. It is a longitudinal cross-sectional view which shows the state of a bushing at the time of the cable for electrical charging installation. It is a perspective view of the grounding adapter which concerns on embodiment of this invention. It is a perspective view of the earthing jig at the time of cleaning concerning an embodiment of the invention.

Explanation of symbols

1: Grounding adapter 101: Cylindrical portion, 102: ridge 102a: screw hole, 102b: grounding wire connection hole 103: screw, 104: grounding lead wire 2: cleaning grounding jig 201: cup-shaped portion, 202: Small-diameter rod-like portion 203: Grounding lead wire 10: Bushing 11: Bushing main body 12: Power supply cable connection port 13: Power transmission cable connection port 14: Device side internal electrode 15: Cable side internal electrode 16: Internal interface, 17: External interface 20: Lower wall surface 30: Power supply cable, 40: Power transmission cable 50: Connection conductor, 60: Insulation plug 70: Bar-shaped operation tool 80: Insulation spacer for disconnection

Claims (7)

When replacing the connection conductor constituting the disconnecting function part of the bushing and the insulating spacer for disconnection, a grounding adapter that is detachably fixed to the bushing and grounds the cable side internal electrode that constitutes the disconnecting function part,
The connecting conductor and the disconnecting insulating spacer have a hollow that can be inserted and removed, and the cylindrical portion is inserted into the cable connection port for power application of the bushing and the tip thereof is in electrical contact with the cable-side internal electrode A grounding adapter characterized by comprising:   The cylindrical portion is provided with a flange at the rear end thereof, and the flange has a fixing hole, and can be attached to and detached from the entrance portion of the cable connection port by the screw through the hole. The grounding adapter according to claim 1, wherein the grounding adapter is fixed.   The grounding adapter according to claim 2, wherein the hook has a grounding wire connection hole for connecting a grounding wire.   The grounding adapter according to any one of claims 1 to 3, wherein the grounding adapter is inserted into the cable connection port for charging of the bushing, and is detachably fixed to the bushing, and the tip thereof is attached to the cable side internal electrode. After the electrical contact is made and grounded, the connection conductor is removed, the disconnecting insulating spacer is attached to the position where the connection conductor was attached, and then the grounding adapter is removed. How to attach the cable for charging to the bushing. The grounding adapter according to any one of claims 1 to 3, wherein the grounding adapter is inserted into the cable connection port for charging of the bushing, and is detachably fixed to the bushing, and the tip thereof is attached to the cable side internal electrode. after taking the ground by electrical contact, remove the insulating spacer for the disconnector, installed in a position before Kidanro insulating spacer is attached to the connection conductor, then a step of removing the ground adapter The method of removing the cable for charging from the bushing characterized by the above-mentioned.
  After removing the grounding adapter, a cleaning grounding jig comprising a cup-shaped part or a cylindrical part and a small-diameter bar-shaped part having the cup-shaped part or the cylindrical part at the tip thereof is used for applying power to the bushing. After being inserted into a cable connection port and fixed to the bushing so as to be detachable, the cup-shaped part or the cylindrical part is brought into electrical contact with the cable-side internal electrode and grounded, and then the cable for charging 5. The method of attaching a power-applying cable to the bushing according to claim 4, further comprising a step of performing a cleaning operation of the connection port and then removing the grounding jig for cleaning.   After removing the grounding adapter, a cleaning grounding jig comprising a cup-shaped part or a cylindrical part and a small-diameter bar-shaped part having the cup-shaped part or the cylindrical part at the tip thereof is used for applying power to the bushing. After being inserted into a cable connection port and fixed to the bushing so as to be detachable, the cup-shaped part or the cylindrical part is brought into electrical contact with the cable-side internal electrode and grounded, and then the cable for charging 6. The method of removing a power-applying cable from a bushing according to claim 5, further comprising the step of cleaning the connection port and then removing the grounding jig for cleaning.

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