JP5798019B2 - Gas insulated switchgear - Google Patents

Description

  Embodiments described herein relate generally to a gas-insulated switchgear having a small current switching performance even when the switching speed is low.

  2. Description of the Related Art Conventionally, switchgears such as disconnect switches and ground switches that use gas-insulated switchgear have been obligated to cut off small currents such as loop currents. Even if it is a small current, the opening / closing speed is set to a high speed of 1 to 2 m / s in order to suppress the consumption of the electrode due to the arc and complete the interruption (see, for example, Patent Document 1).

  In order to increase the opening / closing speed, the operating force such as the spring of the operating mechanism must be increased. In addition, the mechanical strength of the housing and the electrodes must be increased so as to withstand the impact force during opening and closing. For this reason, the structure of the switchgear is complicated, the number of parts is increased, and it is heavy.

JP-A-2-284321

  The problem to be solved by the present invention is to provide a gas-insulated switchgear capable of opening and closing a small current even at a low switching speed and having a simplified structure. Here, the low speed is set to 0.1 m / s or less, which is a speed one digit or more slower than the conventional speed. If the digit of the opening / closing speed is different, the operating force and mechanical strength can be reduced at an accelerated rate.

In order to solve the above problems, a gas-insulated switchgear according to an embodiment is a gas-insulated switchgear constituted by a fixed electrode part and a movable electrode part arranged in the axial direction of the fixed electrode part. The fixed-side electrode portion includes a support insulator having one end fixed to the box, and a fixed-side electrode fixed to the other end of the support insulator and provided with a first recess in the axial direction. And an arc electrode fixed to the bottom surface of the first recess, and a first arc-resistant electrode fixed to the tip of the arc electrode, wherein the movable electrode portion has an inner diameter of the first recess. A movable side electrode having a second recess having a smaller outer diameter and a larger inner diameter than the outer diameter of the arc electrode, a second arc-resistant electrode fixed to the tip of the movable side electrode, and the movable is fixed to the side electrode, it is composed of an insulating rod which is connected to the operating mechanism The support insulator is the fixed electrode, the movable-side electrode and the opposing surfaces, characterized in that a arc resistance insulating material.

Sectional drawing which shows the structure of the gas insulated switchgear concerning Example 1 of this invention. The figure explaining operation | movement of the gas insulated switchgear concerning Example 1 of this invention. Sectional drawing which shows the structure of the gas insulated switchgear concerning Example 2 of this invention.

  Embodiments of the present invention will be described below with reference to the drawings.

  First, a gas insulated switchgear according to Embodiment 1 of the present invention will be described with reference to FIGS. FIG. 1 is a cross-sectional view showing the configuration of a gas insulated switchgear according to Embodiment 1 of the present invention, and FIG. 2 is a diagram for explaining the operation of the gas insulated switchgear according to Embodiment 1 of the present invention. The gas insulated switchgear will be described using a ground switch.

  As shown in FIG. 1, the ground switch includes a fixed-side electrode portion 1a connected to the main circuit, and a movable-side electrode portion connected to a ground electrode arranged opposite to the axial direction of the fixed-side electrode portion 1a. 1b.

  The fixed-side electrode portion 1a is provided with a rod-like support insulator 2, and one end is formed on a convex portion 2a protruding upward in the figure. A hemispherical fixed-side electrode 3 is fixed to the convex portion 2a, and the hemispherical surface is opposed to the movable-side electrode portion 1b so that electric field relaxation is achieved. A first concave portion 3a is provided in the axial direction of the central portion of the hemispherical surface, and a rod-shaped arc electrode 4 is fixed to the bottom thereof. A first arc-resistant electrode 5 made of, for example, a copper-tungsten alloy is fixed to the tip of the arc electrode 4 and protrudes from the fixed-side electrode 3. A band-shaped first contactor 6 is provided on the inner peripheral surface of the first recess 3a.

  A rod-shaped energizing electrode 7 is fixed on the aspherical surface side of the fixed side electrode 3. The energizing electrode 7 is provided with a finger-shaped second contactor 8 so that the main circuit conductor 9 connected to the storage device is energized. An electric field relaxation shield 10 is provided around the energizing electrode 7 and the second contact 8 and is fixed to the fixed side electrode 3.

  The other end of the support insulator 2 is fixed to the flange 11. The flange 11 is airtightly fixed to the opening of the box 12 that encloses an insulating gas such as SF6 gas.

  The movable electrode portion 1b is provided with a rod-shaped movable electrode 13 that is movable in the axial direction. A second recess 13a is provided at the tip of the movable electrode 13 facing the fixed electrode 1a. The inner diameter of the second recess 13a is larger than the outer diameter of the arc electrode 4, and the inner diameter of the first recess 3a. The outer diameter is small, and the arc electrode 4 can be inserted into the second recess 13a and can be inserted into the first recess 3a. An annular second arc-proof electrode 14 made of the same material as the first arc-proof electrode 5 is provided at the tip of the second recess 13a. An insulating rod 15 is fixed to the other end of the movable electrode 13 in the axial direction. The insulating rod 15 penetrates the flange 11 while being airtight, and is connected to an operation mechanism (not shown).

  A cylindrical ground electrode 16 having an inner diameter slightly larger than the outer diameter of the movable electrode 13 is provided around the movable electrode 13. One end of the ground electrode 16 facing the fixed electrode portion 1a is formed in a hemispherical shape for electric field relaxation, and the other end is fixed to the flange 11 and connected to a ground electrode (not shown). A band-shaped third contact 17 is provided on the inner surface, and the movable electrode 13 is in sliding contact.

  Next, the operation will be described with reference to FIG.

  FIG. 2A shows a connected state, in which the movable side electrode 13 moves to and contacts the fixed side electrode 3 side, and the main circuit is grounded. The energization path is as follows: main circuit conductor 9 → fixed side electrode 3 → first contact 6 → movable electrode 13 → third contact 17 → ground electrode 16.

  FIG. 2 (b) shows the moving movement of the movable electrode 13, and when the dielectric breakdown distance is reached, an arc 18 is generated between the first arc-resistant electrode 5 and the second arc-resistant electrode 14. The arc current is a small current region corresponding to the responsibility of the disconnector described later. When the movable electrode 13 is further moved, the state shown in FIG.

  Here, since the first arc-proof electrode 5 protrudes, for example, about 5 mm from the fixed-side electrode 3, the electric field is high, and the arc 18 is easily ignited between the arc-proof electrodes 5 and 14. In addition, since the power supply side has a rod-like shape and the ground side has an annular electrode arrangement, the arc 18 moves along the ring shape, and ignition to the fixed side electrode 3 and the ground electrode 16 can be prevented. In the arc-resistant electrodes 5 and 14, wear due to the arc 18 is suppressed.

  Thus, even if the arc 18 is generated for a long time of several seconds, the arc-proof electrodes 5 and 14 can withstand it, and the opening / closing speed of the movable electrode 13 can be set to a low speed of 0.1 m / s or less. it can. Such a speed can be obtained by a simple motor operation. Further, since the first contactor 6 and the third contactor 17 are not directly exposed to the arc 18, the contact resistance is not affected.

  According to the gas-insulated switchgear of the first embodiment, the first arc-resistant electrode 5 is provided at the center of the fixed electrode 3, the second arc-resistant electrode 14 is also provided on the movable electrode 13, and the arc 18 Is generated in the meantime, the opening / closing speed of the movable electrode 13 can be made low, and the structure of the operation mechanism, the housing, and the like can be simplified.

  In the first embodiment, the gas-insulated switchgear is described using a ground switch. However, the present invention can also be applied to a disconnector in which the movable electrode 13 side is insulated from the flange 11 to form a main circuit. That is, the fixed side electrode 3 is connected to one main circuit, and the movable side electrode 13 is connected to the other main circuit. In the disconnector, for example, 300V-200A loop current, 48.5kV-1A lead small current, 1kV-200A electromagnetic induction current, 3kV-0.4A electrostatic induction current, etc. However, any small current can be opened and closed at a low speed of 0.1 m / s or less. In the electrostatic induction current test, it was possible to cut off at 0.01 m / s. In the case of a disconnector, the curvature of the tip of the ground electrode 16 is the same as that on the fixed side, and the electric field is reduced.

  Next, a gas insulated switchgear according to Embodiment 2 of the present invention will be described with reference to FIG. FIG. 3 is a cross-sectional view showing a configuration of a gas insulated switchgear according to Embodiment 2 of the present invention. Note that Example 2 is different from Example 1 in that an arc resistant material is provided on the surface of the support insulator. In FIG. 3, the same components as those in the first embodiment are denoted by the same reference numerals, and detailed description thereof is omitted.

  As shown in FIG. 3, an arc resistant insulator 19 such as a fluororesin or an amino resin is provided on the surface of the support insulator 2 facing the fixed side electrode 3 or the movable side electrode 13.

  According to the gas insulated switchgear of the second embodiment, in addition to the effects of the first embodiment, even if the arc is diffused and close to the surface of the support insulator 2, it is insulated by the arc resistant insulator 19. The deterioration of characteristics can be prevented.

  According to the embodiment described above, a small current can be opened and closed at a low speed, and the structure of the operation mechanism, the housing, and the like can be simplified.

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

DESCRIPTION OF SYMBOLS 1a Fixed side electrode part 1b Movable side electrode part 2 Support insulator 2a Convex part 3 Fixed side electrode 3a 1st recessed part 4 Arc electrode 5 1st arc-resistant electrode 6 1st contactor 7 Current supply electrode 8 2nd contact Element 9 Main circuit conductor 10 Electric field relaxation shield 11 Flange 12 Box 13 Movable electrode 13a Second recess 14 Second arc-resistant electrode 15 Insulating rod 16 Ground electrode 17 Third contactor 18 Arc 19 Arc-resistant insulator

Claims (1)

A fixed-side electrode part;
A gas-insulated switchgear comprising a movable side electrode portion arranged in the axial direction of the fixed side electrode portion,
The fixed-side electrode part has a support insulator whose one end is fixed to the box,
A fixed-side electrode fixed to the other end of the support insulator and provided with a first recess in the axial direction;
An arc electrode fixed to the bottom surface of the first recess;
A first arc-resistant electrode fixed to the tip of the arc electrode;
The movable side electrode portion has a second concave portion whose outer diameter is smaller than the inner diameter of the first concave portion and whose inner diameter is larger than the outer diameter of the arc electrode; and
A second arc-proof electrode fixed to the tip of the movable electrode;
It is composed of an insulating rod fixed to the movable side electrode and connected to an operation mechanism ,
A gas insulated switchgear characterized in that an arc-resistant insulator is provided on a surface of the support insulator facing the fixed side electrode and the movable side electrode .

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