WO2022044424A1

WO2022044424A1 - Gas-insulated switching device

Info

Publication number: WO2022044424A1
Application number: PCT/JP2021/015967
Authority: WO
Inventors: 淳額賀; 隆浩西村; 健岩田
Original assignee: 株式会社日立製作所
Priority date: 2020-08-24
Filing date: 2021-04-20
Publication date: 2022-03-03
Also published as: JP7393310B2; JP2022036644A

Abstract

The present invention provides a gas-insulated switching device that has an arc-driving-type disconnector that prevents the ignition of an arc at a location where the arc driving force in a spiral electrode is weak and uses the spiral electrode with improved current breaking performance. This gas-insulated switching device is characterized by having the disconnector that has a sealed container in which an insulative gas is sealed, and a pair of arc contacts which are arranged facing each other inside the sealed container, wherein at least one of the pair of arc contacts serves as the spiral electrode that has a spiral groove formed in a direction rotating about a shaft of the arc contact, and the height of the root of a spiral section in the facing surface direction is reduced compared to the height of the tip of the spiral section in the facing surface direction.

Description

Gas insulation switchgear

The present invention relates to a gas-insulated switchgear having a disconnector.

In facilities such as high-voltage power plants and high-voltage substations that have high-voltage and large-capacity power systems as equipment, gas-insulated switchgear is installed to protect these facilities. In recent years, gas-insulated switchgear is required to be compact from the viewpoint of application to underground in urban areas and improvement of economy.

Generally, an arc electrode is installed in the disconnector of the gas-insulated switchgear. The arc electrode controls an arc discharge path that suppresses damage to the main contactor for energization and the shield for electric field relaxation due to the arc discharge generated during the opening operation.

The disconnector has a fixed arc electrode installed on the fixed side and a movable arc electrode installed on the movable side, and electrically connects between the fixed arc electrode and the movable arc electrode.

And, in order to improve the current cutoff performance, a spiral electrode that uses a permanent magnet, generates a magnetic field, and uses electromagnetic force may be used for the arc electrode.

As a background technology in such a technical field, there is Japanese Patent Application Laid-Open No. 2008-176942 (Patent Document 1). In Patent Document 1, a gas-insulated switchgear in which a facing-side insulating member is installed on the facing surface side of a non-contact recess in a spiral electrode, and a back-side insulating member having an outer diameter equal to or larger than that of the spiral electrode is installed on the back surface side of the spiral electrode. The device is described (see summary).

Japanese Unexamined Patent Publication No. 2008-176942

Patent Document 1 describes a gas-insulated switching device in which a spiral electrode is installed as an arc electrode and an arc current is energized along the spiral portion of the spiral electrode to rotate the arc and improve the current cutoff performance. Has been done.

Generally, in an arc-driven disconnector that uses a spiral electrode, there is a risk that the arc will land at any point in the circumferential direction of the spiral portion.

Generally, the arc driving force in an arc-driven disconnector using a spiral electrode increases the Lorentz force as the arc current flows in the spiral direction, and the arc lands on the tip of the spiral portion. There is a large difference in the arc driving force between the case where the arc is sunk and the case where the arc is isolated at the base of the spiral portion. That is, the Lorentz force of the root portion of the spiral portion having a short spiral current path is smaller than that of the tip portion of the spiral portion having a long spiral current path.

When the arc is sunk at the base of the spiral part where the Lorentz force is small, the arc driving force is weaker and the rotational movement of the arc is stronger than when the arc is sunk at the tip of the spiral part where the Lorentz force is large. It becomes smaller, the effect of the spiral electrode is reduced, and the arc time and the amount of electrode melting may increase.

In other words, in order to improve the current cutoff performance of an arc-driven disconnector that uses a spiral electrode, where the breaking current will increase more and more in the future, the arc will be isolated at a location where the arc driving force of the spiral electrode is weak. Need to prevent.

However, Patent Document 1 does not describe a gas-insulated switchgear having a disconnector that prevents the arc from being isolated in a place where the arc driving force of the spiral electrode is weak.

Therefore, the present invention provides a gas-insulated switchgear having an arc-driven disconnector that uses a spiral electrode to prevent arc from being isolated in a place where the arc driving force of the spiral electrode is weak and to improve current cutoff performance. do.

In order to solve the above-mentioned problems, the gas-insulated opening / closing device of the present invention has a closed container for enclosing an insulating gas and a pair of arc contacts installed facing the inside of the closed container, and has a pair. At least one of the arc contacts of the above is a spiral electrode having a spiral groove formed in a direction of rotation around the axis of the arc contact, and the height of the spiral portion of the spiral electrode in the direction of the facing surface is set to the spiral. It is characterized by having a breaker that is lower than the height of the tip of the spiral portion of the electrode in the direction of the facing surface.

INDUSTRIAL APPLICABILITY According to the present invention, there is provided a gas-insulated switchgear having an arc-driven disconnector that uses a spiral electrode to prevent arc from being isolated in a place where the arc driving force of the spiral electrode is weak and to improve current cutoff performance. can do.

Issues, configurations and effects other than those mentioned above will be clarified by the explanation of the examples below.

It is a plane (front) view explaining the movable side spiral electrode 1 which the disconnector 100 described in Example 1 has. FIG. 5 is a cross-sectional (side) view illustrating the movable side spiral electrode 1 included in the disconnector 100 described in the first embodiment. It is a plane (front) view explaining the fixed side spiral electrode 5 included in the disconnector 100 described in Example 1. FIG. FIG. 5 is a cross-sectional (side) view illustrating the fixed side spiral electrode 5 included in the disconnector 100 described in the first embodiment. It is a top view explaining the arc current which flows when the arc is isolated on the movable side spiral electrode 1 of FIG. 1A described in Example 1. FIG. It is a top view explaining the arc current which flows when the arc is isolated on the fixed side spiral electrode 5 of FIG. 2A described in Example 1. FIG. It is explanatory drawing explaining the analysis result of the Lorentz force received by the arc by the landing position of the arc described in Example 1. FIG. It is sectional drawing (side surface) diagram schematically explaining the schematic structure of the disconnector 100 described in Example 1. FIG. FIG. 3 is a cross-sectional (side surface) view illustrating a main portion (closed pole state) of the disconnector 100 described in the first embodiment in an enlarged manner. FIG. 3 is a cross-sectional (side surface) view illustrating a main portion (state in the middle of opening a pole) of the disconnector 100 described in the first embodiment in an enlarged manner. It is explanatory drawing schematically explaining the magnetic field formed by the arc current flowing through the spiral electrode described in Example 1. FIG. It is sectional drawing explaining the movable side spiral electrode 1 which the disconnector 100 described in Example 2 has. It is sectional drawing explaining the fixed side spiral electrode 5 included in the disconnector 100 described in Example 2. FIG. It is sectional drawing explaining the main part (state in the process of opening pole) of the disconnector 100 described in Example 3 in an enlarged manner.

Hereinafter, examples of the present invention will be described with reference to the drawings. It should be noted that substantially the same or similar configurations are designated by the same reference numerals, and if the explanations are duplicated, the explanations may be omitted.

First, the movable side spiral electrode 1 included in the disconnector 100 described in the first embodiment will be described.

FIG. 1A is a plan (front) view illustrating the movable side spiral electrode 1 included in the disconnector 100 described in the first embodiment, and FIG. 1B is a plan view (front) view of the movable side spiral electrode 1 included in the disconnector 100 described in the first embodiment. It is sectional drawing (side surface) view explaining 1.

The movable side spiral electrode 1 is made of a metal having arc resistance, and the spiral groove 2 is formed in two directions (2a, 2b) clockwise from the central portion to the outer peripheral portion.

The movable side spiral electrode 1 is used as a movable side arc contactor (hereinafter referred to as a movable side arc electrode), and the spiral groove 2 formed in the movable side spiral electrode 1 is around the axis of the movable side arc electrode. It is formed in the direction of rotation.

The movable side spiral electrode 1 is an electrode (spiral electrode 1) that is installed as a movable side arc electrode and has a spiral groove (spiral groove 2) cut in a substantially disk electrode as an arc traveling portion. Then, by energizing the arc current along the spiral portion (the portion other than the spiral groove 2), the arc is rotated and the current cutoff performance is improved.

The movable side spiral electrode 1 has a spiral groove 2 and a spiral portion, and the height of the root portion 4 of the spiral portion in the facing surface direction is compared with the height of the tip portion 3 of the spiral portion in the facing surface direction. make low.

In Example 1, the surface of the root portion 4 of the spiral portion (the surface facing the fixed-side spiral electrode 5) is a flat surface.

That is, the height of the movable side spiral electrode 1 is lowered toward the electrode facing surface of the root portion 4 of the spiral portion with respect to the height of the tip portion 3 of the spiral portion toward the electrode facing surface. The movable side spiral electrode 1 has a height in the facing surface direction of the tip portion 3 of the electrode portion (spiral portion) constituting the spiral, and a facing surface direction of the base portion 4 of the electrode portion (spiral portion) constituting the spiral. Lower the height of the.

Thereby, the electric field of the root portion 4 of the spiral portion can be made relatively lower than the electric field of the tip portion 3 of the spiral portion. As a result, the arc formation can be concentrated on the tip portion 3 of the spiral portion.

Next, the fixed-side spiral electrode 5 included in the disconnector 100 described in the first embodiment will be described.

FIG. 2A is a plan view (front view) for explaining the fixed-side spiral electrode 5 included in the disconnector 100 described in the first embodiment, and FIG. 2B is a plan view (front) view of the fixed-side spiral electrode 5 included in the disconnector 100 described in the first embodiment. 5 is a cross-sectional (side surface) view illustrating 5.

The fixed-side spiral electrode 5 is made of an arc-resistant metal, and the spiral groove 2 is formed in two directions (2a, 2b) counterclockwise from the central portion to the outer peripheral portion.

The fixed-side spiral electrode 5 is used as a fixed-side arc contactor (hereinafter referred to as a fixed-side arc electrode), and the spiral groove 2 formed in the fixed-side spiral electrode 5 is formed around the axis of the fixed-side arc electrode. It is formed in the direction of rotation.

The fixed side spiral electrode 5 is an electrode (spiral electrode 5) that is installed as a fixed side arc electrode and has a spiral groove (spiral groove 2) cut in a substantially disk electrode as an arc traveling portion. Then, by energizing the arc current along the spiral portion (the portion other than the spiral groove 2), the arc is rotated and the current cutoff performance is improved.

The fixed-side spiral electrode 5 has a spiral groove 2 and a spiral portion, and the height of the root portion 4 of the spiral portion in the facing surface direction is compared with the height of the tip portion 3 of the spiral portion in the facing surface direction. make low.

In the first embodiment, the surface of the root portion 4 of the spiral portion (the surface facing the movable side spiral electrode 1) is a flat surface.

That is, the height of the fixed-side spiral electrode 5 is lowered toward the electrode facing surface of the root portion 4 of the spiral portion with respect to the height of the tip portion 3 of the spiral portion toward the electrode facing surface. The fixed-side spiral electrode 5 has a height in the facing surface direction of the tip portion 3 of the electrode portion (spiral portion) constituting the spiral, and a facing surface direction of the base portion 4 of the electrode portion (spiral portion) constituting the spiral. Lower the height of the.

When the movable side spiral electrode 1 shown in FIG. 1 and the fixed side spiral electrode 5 shown in FIG. 2 are installed facing each other, the magnetic fields formed by the arc currents flowing through the respective electrodes are strengthened and the spiral electrodes are formed. A magnetic field is formed in the radial direction from the center of the.

As a result, when the disconnector 100 is opened to the pole with the movable side spiral electrode 1 and the fixed side spiral electrode 5 facing each other, the distance between the poles of the root portion 4 of the spiral portion is set to the tip portion of the spiral portion. It is longer than the distance between the poles of 3, and the root portion 4 of the spiral portion has a concave shape (state) with respect to the tip portion 3 of the spiral portion. The distance between the poles is the distance between the opposite movable side spiral electrode 1 and the fixed side spiral electrode 5.

Therefore, due to the voltage difference generated between the poles, the electric field at the base 4 of the spiral portion is relatively lower than the electric field at the tip 3 of the spiral portion. Since the arc locates at a place where the electric field strength is high, the arc preferentially locates at the tip portion 3 of the spiral portion rather than the root portion 4 of the spiral portion.

When the spiral groove 2 is formed in two directions from the central portion to the outer peripheral portion, the root portion 4 of the spiral portion (the region where the height is relatively lower than the tip portion 3 of the spiral portion). Is preferably 5 degrees or more and 44 or less in the circumferential direction, and the tip portion 3 of the spiral portion (the region where the height is relatively higher than the root portion 4 of the spiral portion) is in the circumferential direction. It is preferable that the temperature is 136 degrees or more and 175 degrees or less. As a result, it is possible to prevent the arc from being deposited in a place where the arc driving force of the spiral electrode is weak, and to improve the current cutoff performance.

The root portion 4 of the spiral portion and the tip portion 3 of the spiral portion may be manufactured by cutting a portion that becomes the root portion 4 of the spiral portion, or the portion that becomes the tip portion 3 of the spiral portion and the spiral portion. A mold may be formed so as to have a portion to be a root portion 4 of the mold, and the mold may be manufactured by casting.

The height of the root portion 4 of the spiral portion is equal to or higher than the height of the spiral portions other than the tip portion 3 of the spiral portion.

When the movable side spiral electrode 1 and the fixed side spiral electrode 5 face each other (closed pole state), the base portion 4 of the spiral portion of the movable side spiral electrode 1 and the root portion 4 of the spiral portion of the fixed side spiral electrode 5 are formed. Is at the same position, and the tip portion 3 of the spiral portion of the movable side spiral electrode 1 and the tip portion 3 of the spiral portion of the fixed side spiral electrode 5 are at the same position.

Next, the arc current that flows when the arc is isolated from the movable side spiral electrode 1 of FIG. 1A described in the first embodiment will be described.

FIG. 3A is a plan view illustrating an arc current that flows when an arc is stranded on the movable side spiral electrode 1 of FIG. 1A described in the first embodiment.

As shown in FIG. 3A, when the arc lands on the tip portion 3 (point isolated portion 6) of the spiral portion (spiral outer peripheral portion) of the movable side spiral electrode 1, the arc is directed from the dotted portion 6 toward the central portion 7. Then, an arc current 8 flows through the movable side spiral electrode 1.

Next, the arc current that flows when the arc is isolated from the fixed side spiral electrode 5 of FIG. 2A described in the first embodiment will be described.

FIG. 3B is a plan view illustrating an arc current that flows when an arc is isolated from the fixed side spiral electrode 5 of FIG. 2A described in the first embodiment.

As shown in FIG. 3B, when the arc lands on the tip portion 3 (point isolated portion 6) of the spiral portion (spiral outer peripheral portion) of the fixed side spiral electrode 5, the arc is directed from the central portion 7 toward the point isolated portion 6. Then, the arc current 9 flows through the fixed side spiral electrode 5.

As shown in FIGS. 3A and 3B, between the tip portion 3 (dotted portion 6) of the spiral portion of the movable side spiral electrode 1 and the tip portion 3 (dotted portion 6) of the spiral portion of the fixed side spiral electrode 5. When the arc is isolated, an arc current flows from the point 6 toward the central portion 7 through the movable side spiral electrode 1 as an arc current 8, and the arc current flows from the central portion 7 to the central portion 7. A spiral electrode 5 on the fixed side flows toward 6 as an arc current 9, and is connected to an arc.

In this way, by configuring the spiral electrode as in the first embodiment, that is, by installing the movable side spiral electrode 1 shown in FIG. 1 and the fixed side spiral electrode 5 shown in FIG. 2 so as to face each other. The magnetic field formed by the arc current flowing through each spiral portion strengthens between the opposing movable side spiral electrode 1 and the fixed side spiral electrode 5, and a magnetic field directed in the radial direction from the center of the spiral electrode is formed. To.

Then, due to the Lorentz force due to such a magnetic field and current, the arc receives an arc driving force in the circumferential direction of the spiral electrode.

As a result, according to the first embodiment, the distance through which the arc current flows in the spiral direction becomes longer, the Lorentz force becomes larger, and the arc driving force becomes larger and stronger. Then, the arc discharge is not fixed in the isolated place, the arc is cooled, the resistance due to stretching increases, the rotational motion of the arc increases, the effect of the spiral electrode also increases, and the arc time and electrode melting The amount is also reduced.

Next, the analysis result of the Lorentz force received by the arc due to the landing position of the arc described in Example 1 will be described.

FIG. 4 is an explanatory diagram illustrating the analysis result of the Lorentz force received by the arc due to the landing position of the arc described in the first embodiment.

As shown in FIG. 4, at the root portion 4 of the spiral portion, the Lorentz force is reduced to about 1/3 with respect to the tip portion 3 of the spiral portion.

Therefore, in the first embodiment, the protruding height of the root portion 4 of the spiral portion in the facing direction is made lower than the protruding height of the tip portion 3 of the spiral portion in the facing direction, thereby lowering the protruding height of the root portion 4 of the spiral portion. The electric field of is relatively low as compared with the electric field of the tip portion 3 of the spiral portion.

As a result, the probability that the arc will land on the tip 3 of the spiral portion is higher than the probability that the arc will land on the root 4 of the spiral portion, and the arc driving force can be increased.

Further, the number (direction) of the spiral grooves 2 formed on the spiral electrode may be at least one (one direction) or more. In the first embodiment, there are two directions.

Further, the direction of the spiral groove 2 formed in the movable side spiral electrode 1 and the direction of the spiral groove 2 formed in the fixed side spiral electrode 5 are opposite to each other. For example, if the direction of the spiral groove 2 formed in the movable side spiral electrode 1 is clockwise, the direction of the spiral groove 2 formed in the fixed side spiral electrode 5 is counterclockwise, and the spiral groove 2 is formed in the movable side spiral electrode 1. If the direction of the spiral groove 2 is counterclockwise, the direction of the spiral groove 2 formed on the fixed side spiral electrode 5 is clockwise.

Further, in the cross section of the spiral electrode, the movable side spiral electrode 1 and the fixed side spiral electrode 5 are formed by the spiral outer peripheral portion of the spiral electrode (the outer peripheral portion of the spiral portion: the tip portion 3 of the spiral portion and the root portion 4 of the spiral portion). In the area where the arc is formed), make it concave so that the arc is isolated.

Next, the schematic configuration of the disconnector 100 described in the first embodiment will be schematically described.

FIG. 5 is a cross-sectional (side) view schematically illustrating the schematic configuration of the disconnector 100 described in the first embodiment. Note that FIG. 5 shows a closed pole state of the disconnector 100.

The disconnector 100 described in the first embodiment is an arc drive type disconnector that uses a spiral electrode (a spiral electrode that uses a permanent magnet to generate a magnetic field and uses an electromagnetic force). Further, the disconnector 100 constitutes a gas-insulated switchgear together with a grounding switchgear and a circuit breaker.

The disconnector 100 has a closed container 10. In the closed container 10, a gas compartment is formed by the insulating spacer 11, and the insulating gas 12 is filled (enclosed) in the gas compartment. The insulating gas includes a negative gas such as SF ₆ having high insulating properties, a SF ₆ / N ₂ mixed gas containing a negative gas such as dry air, nitrogen, carbon dioxide, and SF ₆ , and a negative gas such as SF ₆ . An N ₂ / O ₂ mixed gas or the like that does not contain the above is used.

An embedded conductor 13 is installed in the center of the insulating spacer 11.

Then, in a state of being electrically insulated from the closed container 10, the fixed side high voltage conductor 14 and the movable side high voltage conductor 15 are installed facing each other with a predetermined insulation distance. A fixed-side electric field relaxation shield 16 is installed on the fixed-side high-voltage conductor 14, a movable-side electric field relaxation shield 17 is installed on the movable-side high-voltage conductor 15, and a fixed-side electric field relaxation shield 16 and a movable side are installed. It is installed facing the electric field relaxation shield 17.

The movable side main contactor 21 is installed inside the movable side electric field relaxation shield 17 installed on the movable side high voltage conductor 15. The movable (sliding) inside the movable side main contact 21 is moved (sliding), and the metal movable element 18 is movably installed on the axis thereof via an insulating operation rod 19 by an external actuator (not shown). To.

A fixed-side main contactor 20 is installed inside the fixed-side electric field relaxation shield 16 installed on the fixed-side high-voltage conductor 14.

The fixed side main contact 20 and the movable side main contact 21 always maintain an electrical connection state via the movable element 18. Further, the fixed-side high-voltage conductor 14 and the movable-side high-voltage conductor 15 always maintain an electrical connection state via the fixed-side main contactor 20, the movable-side main contactor 21, and the movable element 18.

Next, the main part of the disconnector 100 described in the first embodiment will be expanded and described.

FIG. 6 is a cross-sectional (side view) view illustrating the main part (closed pole state) of the disconnector 100 described in the first embodiment in an enlarged manner.

Inside the fixed-side main contact 20, a rod 22 for fixing the fixed-side spiral electrode 5, a pedestal 23 for fixing the rod for supporting the rod 22, and a spring installed on the rear surface of the pedestal 23 to press the pedestal 23. 25 and are installed.

The gantry 23 is made of metal and is in contact with the inner peripheral surface of the fixed-side main contact 20 and is electrically connected. The rod 22 is also metal. That is, the fixed-side spiral electrode 5 and the fixed-side main contactor 20 are electrically connected via the rod 22 and the gantry 23.

Then, the fixed-side spiral electrode 5 (fixed-side arc electrode) is fixed to the tip of the rod 22.

On the other hand, the movable side spiral electrode 1 (movable side arc electrode) is fixed to the tip of the mover 18 so as to face the fixed side spiral electrode 5. That is, the movable side spiral electrode 1 and the movable side main contactor 21 are electrically connected via the movable element 18.

The fixed-side spiral electrode 5 and the movable-side spiral electrode 1 are in contact with each other, and the fixed-side main contactor 20 and the movable-side main contactor 21 are electrically connected to each other, resulting in a closed pole state. Then, in the closed pole state, the fixed-side high-voltage conductor 14, the fixed-side main contactor 20, the mover 18, the movable-side main contactor 21, and the movable-side high-voltage conductor 15 form a current passage.

In the closed pole state of the disconnector 100, the tip of the mover 18 penetrates into the fixed side electric field relaxation shield 16 and the mover 18 and the fixed side main contact 20 come into contact with each other.

Here, the current cutoff operation of the disconnector 100 will be described.

In the closed pole state shown in FIG. 5, when the insulating operation rod 19 is rotated clockwise by an external actuator (not shown) and an open pole operating force is applied to the mover 18, the mover 18 moves on its axis. Move to the right (open pole direction).

First, the mover 18 is separated from the fixed side main contact 20, and the current flowing through the contact portion between the fixed side main contact 20 and the mover 18 is cut off.

Since the spring 25 is in the compressed state in the closed pole state, the gantry 23, the rod 22, the fixed side spiral electrode 5, and the movable side spiral electrode 1 are pushed by the spring 25 in the initial stage of the open pole state. As a unit, move to the right following the opening operation of the mover 18.

At this time, the fixed side spiral electrode 5 and the movable side spiral electrode 1 move while being in contact with each other. Therefore, the fixed side high voltage conductor 14, the fixed side main contact 20, the gantry 23, the rod 22, the fixed side spiral electrode 5, the movable side spiral electrode 1, the mover 18, the movable side main contact 21, the movable side high voltage. The conductor 15 forms a current path.

FIG. 7 is a cross-sectional (side surface) view illustrating the main part (state in the middle of opening the pole) of the disconnector 100 described in the first embodiment in an enlarged manner.

As shown in FIG. 7, the gantry 23 stops moving to the right by the fixed-side main contactor 20. As a result, the rod 22 and the fixed-side spiral electrode 5 also stop moving to the right. At this time, the fixed-side spiral electrode 5 is inside the fixed-side electric field relaxation shield 16.
Since the fixed-side spiral electrode 5 is inside the fixed-side electric field relaxation shield 16, the electric field of the fixed-side spiral electrode 5 can be suppressed to a low level and discharge can be suppressed in the open pole state.

After that, due to the opening operation of the mover 18, the movable side spiral electrode 1 and the fixed side spiral electrode 5 are opened, and an arc 24 is generated between the movable side spiral electrode 1 and the fixed side spiral electrode 5. The current cutoff is completed while repeating the re-roll call.

If a high recovery voltage is applied when the current is cut off, recalls or ground faults may occur starting from the high electric field location, and the current cutoff may not be established.

Next, the magnetic field formed by the arc current flowing through the spiral electrode described in Example 1 will be schematically described.

FIG. 8 is an explanatory diagram schematically illustrating a magnetic field formed by an arc current flowing through the spiral electrode described in the first embodiment.

The movable side spiral electrode 1 and the fixed side spiral electrode 5 are installed facing each other with the same center, and the direction of the spiral groove 2 formed in the movable side spiral electrode 1 and the spiral formed in the fixed side spiral electrode 5. The direction is opposite to the direction of the groove 2. For example, if the direction of the spiral groove 2 formed in the movable side spiral electrode 1 is clockwise, the direction of the spiral groove 2 formed in the fixed side spiral electrode 5 is counterclockwise, and the direction of the spiral groove 2 is counterclockwise in the movable side spiral electrode 1. If the direction of the spiral groove 2 formed is counterclockwise, the direction of the spiral groove 2 formed in the fixed side spiral electrode 5 is clockwise.

The current I flows from the rod 22 through the tip of the rod 22 to the fixed-side spiral electrode 5 in the Z-axis direction in FIG. 8, and the current I flows from the movable-side spiral electrode 1 to the mover 18 of the mover 18. It flows through the tip portion to the mover 18 in the Z-axis direction in FIG.

Further, the arc 24 is generated between the fixed side spiral electrode 5 and the movable side spiral electrode 1.

As shown in FIG. 8, since the spiral groove 2 is formed in the opposite direction between the fixed side spiral electrode 5 and the movable side spiral electrode 1, the spiral groove 2 is formed.
(1) In the fixed-side spiral electrode 5, an arc current 9 flows toward the front of the paper surface above the central axis (Z axis), and an arc current flows toward the depth of the paper surface below the central axis (Z axis). 9 flows,
(2) In the movable side spiral electrode 1, an arc current 8 flows in the depth direction of the paper surface above the central axis (Z axis), and an arc current flows toward the front side of the paper surface below the central axis (Z axis). 8 flows.

Therefore, a magnetic field B is generated in the radial direction (direction orthogonal to the direction in which the current I flows) from the central axis (Z axis), and the magnetic driving force F (F (arc driving force) = I × B) is generated in the arc. Works. That is, the arc 24 receives the arc driving force F in the circumferential direction of the spiral electrode (circumferential direction of the central axis (Z axis)) by the Lorentz force F due to the magnetic field B and the current I.

As described above, the circuit breaker 100 described in the first embodiment has a closed container 10 for enclosing the insulating gas 12 and a pair of arc electrodes (movable side arc electrode and fixed) installed facing the inside of the closed container 10. Spiral electrode (movable side spiral electrode) having a side arc electrode) and having a spiral groove 2 formed in a direction in which both (or at least one of them) of the pair of arc electrodes are rotated around the axis of the arc electrode. 1 and / or the fixed side spiral electrode 5). Then, the height of the root portion 4 of the spiral portion of the spiral electrode in the facing surface direction is made lower than the height of the tip portion 3 of the spiral portion of the spiral electrode in the facing surface direction.

By installing the movable side spiral electrode 1 shown in FIG. 1 and the fixed side spiral electrode 5 shown in FIG. 2 facing each other, the distance through which the arc current flows in the spiral direction becomes longer, the Lorentz force becomes larger, and the arc driving force becomes larger. ,Become stronger. Then, the rotational movement of the arc also increases, and the effect of the spiral electrode increases.

According to the first embodiment, when the disconnector 100 is opened, the arc landing position on the spiral electrode can be set to a place where the arc driving force is strong, and stable current cutoff performance can be obtained.

Further, according to the first embodiment, since the arc is sunk in a place where the electric field strength is high, the arc is sunk in the tip portion 3 of the spiral portion preferentially over the root portion 4 of the spiral portion. become. Then, the arc can be concentrated on the tip 3 of the spiral portion, the arc can be prevented from being anchored to the portion where the arc driving force of the spiral electrode is weak (the root portion 4 of the spiral portion), and the rotation of the arc can be prevented. It is possible to increase the motion and improve the current cutoff performance (performance that can cut off the arc discharge efficiently in a short time).

Thereby, it is possible to provide the disconnector 100 which improves the current cutoff performance and improves the reliability. The disconnector 100 can reduce the size and weight of the external actuator, and can reduce the operating force of the external actuator.

Next, the spiral electrode included in the disconnector 100 described in Example 2 will be described.

FIG. 9A is a cross-sectional view illustrating the movable side spiral electrode 1 included in the disconnector 100 described in the second embodiment.

Although the surface of the base portion 4 of the spiral portion formed on the movable side spiral electrode 1 described in Example 1 is flat, the root portion 4 of the spiral portion formed on the movable side spiral electrode 1 described in Example 2 is flat. The surface (the surface facing the fixed side spiral electrode 5) is a curved surface (cross-sectional shape with rounded corners). That is, the surface of the root portion 4 has a smooth curved shape with no corners in the cross section.

This reduces the electric field concentration. Then, the arc formation can be concentrated on the tip portion 3 of the spiral portion, and a stable arc driving force can be obtained.

FIG. 9B is a cross-sectional view illustrating the fixed-side spiral electrode 5 included in the disconnector 100 described in the second embodiment.

Although the surface of the root portion 4 of the spiral portion formed on the fixed-side spiral electrode 5 described in Example 1 is flat, the root portion 4 of the spiral portion formed on the fixed-side spiral electrode 5 described in Example 2 is flat. The surface (the surface facing the movable side spiral electrode 1) is a curved surface (cross-sectional shape with rounded corners). That is, the surface of the root portion 4 has a smooth curved shape with no corners in the cross section.

Next, the main part (state in the middle of opening the pole) of the disconnector 100 described in the third embodiment will be expanded and described.

FIG. 10 is a cross-sectional view illustrating an enlarged main part (state in the middle of opening the pole) of the disconnector 100 described in the third embodiment.

The disconnector 100 described in the first embodiment has a movable side spiral electrode 1 installed on the movable side and a fixed side spiral electrode 5 installed on the fixed side, but the disconnector 100 described in the third embodiment has a disconnector 100. The fixed side has a fixed side spiral electrode 5 at the tip of the rod 22, and the movable side has a flat plate type movable side arc electrode 26 at the tip of the mover 18. That is, in the third embodiment, the movable side arc electrode is a flat plate type movable side arc electrode.

In the third embodiment, the magnetic driving force is not generated in the movable side arc electrode, but by installing the fixed side spiral electrode 5 shown in FIG. 2 on the fixed side, the electric field concentration is reduced and the withstand voltage between the electrodes is increased. be able to.

That is, when the fixed side spiral electrode 5 alone can sufficiently secure the magnetic driving force and improve the current cutoff performance, the flat plate type movable side arc electrode 26 is installed at the tip of the mover 18. , The magnetic driving force can be secured and the withstand voltage between the electrodes can be increased.

In Example 3, the fixed side spiral electrode 5 shown in FIG. 2 is provided on the fixed side, and the flat plate type movable side arc electrode 26 is provided on the movable side, but the flat plate type fixed side arc electrode is provided on the fixed side. The movable side spiral electrode 1 shown in FIG. 1 may be provided on the movable side.

The present invention is not limited to the above-described embodiment, but includes various modifications. For example, the above-mentioned examples have been described in detail in order to explain the present invention in an easy-to-understand manner, and are not necessarily limited to those having all the described configurations.

Further, it is possible to replace a part of the configuration of one embodiment with a part of the configuration of another embodiment, and it is also possible to add the configuration of another embodiment to the configuration of one embodiment. Is.

1 ... Movable side spiral electrode, 2 ... Spiral groove, 3 ... Spiral part tip part, 4 ... Spiral part root part, 5 ... Fixed side spiral electrode, 6 ... Point isolated part, 7 ... Central part, 8 ... Movable side Arc current, 9 ... fixed side arc current, 10 ... closed container, 11 ... insulating spacer, 12 ... insulating gas, 13 ... embedded conductor, 14 ... fixed side high voltage conductor, 15 ... movable side high voltage conductor, 16 ... Fixed side electric field relaxation shield, 17 ... Movable side electric field relaxation shield, 18 ... Movable element, 19 ... Insulation operation rod, 20 ... Fixed side main contactor, 21 ... Movable side main contactor, 22 ... Rod, 23 ... Frame, 24 ... arc, 25 ... spring, 26 ... flat plate type movable side arc electrode, 100 ... breaker.

Claims

It has a closed container for enclosing an insulating gas and a pair of arc contacts installed facing the inside of the closed container.
At least one of the pair of arc contacts is a spiral electrode having a spiral groove formed in a direction of rotation around the axis of the arc contacts.
Gas insulation characterized by having a disconnector that lowers the height of the base of the spiral portion of the spiral electrode in the facing surface direction with respect to the height of the tip of the spiral portion of the spiral electrode in the facing surface direction. Switchgear.
The gas-insulated switchgear according to claim 1.
Spiral electrodes having the spiral groove are installed in both of the pair of arc contacts.
A gas-insulated switchgear characterized in that the spiral groove formed on the movable side spiral electrode and the spiral groove formed on the fixed side spiral electrode are formed in opposite directions.
The gas-insulated switchgear according to claim 1.
A gas-insulated switchgear characterized in that a spiral electrode is installed on one of the pair of arc contacts, and a flat plate type arc electrode is installed on the other of the pair of arc contacts.
The gas-insulated switchgear according to claim 3.
A fixed side spiral electrode is installed on one fixed side of the pair of arc contacts, and a flat plate type movable side arc electrode is installed on the other movable side of the pair of arc contacts. Gas-insulated switchgear.
The gas-insulated switchgear according to claim 1.
A gas-insulated switchgear characterized in that the region where the height of the root portion is relatively lowered is 5 degrees or more and 44 or less in the circumferential direction.
The gas-insulated switchgear according to claim 1.
A gas-insulated switchgear characterized in that the region in which the height of the tip portion is relatively high is 136 degrees or more and 175 degrees or less in the circumferential direction.
The gas-insulated switchgear according to claim 1.
A gas-insulated switchgear characterized in that the root portion has a curved shape in a cross section.