JPH05344616A - Gas insulated switchgear - Google Patents

Abstract

PURPOSE:To prevent magnetic saturation of magnetic body and to suppress surge at the time of switching through downsizing. CONSTITUTION:A resistor 5 is placed in a current path through which current flows only at the time of switching and a magnetic body 6 is provided surrounding the current path. When a movable contactor 1B is driven to the right on the drawing by an open circuit command and separated from a current collector 3A, current flows through a fixed contactor 1A into the movable contactor 1B. The movable contactor 1B is eventually separated from the fixed contactor 1A and an arc 20 is fired again between the movable contactor 1B and an arc discharge electrode 7. Surge is produced by the restrike but the current is suppressed through the resistor 5 and the surge is absorbed by the magnetic body 6 which is not saturated by the current thus suppressed.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a gas-insulated switchgear, and more particularly to a gas-insulated switchgear configured to suppress surges generated when switching a disconnecting switch or a ground switch.

[0002]

2. Description of the Related Art Generally, a gas-insulated switchgear comprises a switch such as a disconnector or a ground switch in a closed container filled with an insulating gas such as SF ₆ gas, and a high frequency surge is generated when the switch is opened or closed. To do. In particular, the surge that occurs when opening and closing the disconnector is as high as several MHz to several tens of MHz, and the frequency of occurrence is relatively high. When such a surge occurs,
Since the steep overvoltage causes an insulation problem, its suppression is desired.

As a conventional gas-insulated switchgear for suppressing such a surge, for example, Japanese Patent Publication No. 53-38031 discloses a device in which a resistor is inserted in a current passage at the time of opening and closing and the surge is suppressed by this resistance. In addition, JP-A-61
In Japanese Patent Publication No. 254011, a magnetic body is provided so as to surround a current-carrying conductor that serves as a current path at the time of opening and closing, and a surge is suppressed by the magnetic body.

[0004]

However, in the gas insulated switchgear disclosed in Japanese Patent Publication No. 53-38031, the axial length of the resistor that suppresses the surge is large, and therefore the axial length of the entire device is large. It gets bigger. Further, in the gas insulated switchgear disclosed in JP-A-61-254011, when the re-ignition charging current is large, the magnetic substance must be made large in order to suppress the magnetic saturation phenomenon of the magnetic substance. As in the case described above, the size of the entire device is increased.

An object of the present invention is to provide a gas-insulated switchgear which prevents magnetic saturation of a magnetic material and is miniaturized to suppress surges during opening and closing.

[0006]

In order to achieve the above-mentioned object, the present invention arranges a magnetic body so as to surround a current passage through which a current flows when opening and closing, and the above-mentioned magnetic material is provided in a current passage through which a current flows only during opening and closing. A resistor is provided to suppress magnetic saturation of the body.

[0007]

Since the gas-insulated switchgear according to the present invention is configured as described above, the current flowing through the main circuit during steady state flows through the above-mentioned predetermined current path at the time of switching, and the resistance provided in this current path. Since it is limited by the body, magnetic saturation of the magnetic body is suppressed, and the surge suppression effect of the magnetic body enables the resistor to be made smaller in the axial direction. The magnetic material can sufficiently suppress the surge.

[0008]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a vertical cross-sectional view showing a gas insulation disconnector as a gas insulation switchgear according to an embodiment of the present invention. The illustrated portion is configured in a closed container (not shown) filled with an insulating gas such as SF ₆ gas, and a fixed contactor 1A is provided at the center of the main circuit conductor 2 on the left side of the drawing. A current collector 3A is arranged so as to surround the fixed contactor 1A.
In addition, a movable contactor 1B that is axially opened and closed by an operating device (not shown) is provided in the center of the main circuit conductor 4 on the right side so as to be able to come in contact with and separate from the fixed contactor 1A. Collectors 3B and 3C that are constantly in electrical contact with
Are arranged. Further on the outer periphery of the current collector 3A, an arc discharge electrode 7 is fixed to the other end of a resistor 5 having one end connected to the main circuit conductor 2, and a conductor positioned between the resistor 5 and the arc discharge electrode 7. A magnetic body 6 is provided so as to surround 7A. This arc discharge electrode 7 is always movable contact 1
The movable contactor 1B is arranged so as to surround the outer periphery of the movable contactor 1B so as to form a gas space between the movable contactor 1B and B. A plurality of resistors 5 are electrically arranged in parallel between the main circuit conductor 2 and the arc discharge electrode 7, and the magnetic body 6 is arranged on the outer peripheral portion of each conductor 7A. On the opposite sides of the two main circuit conductors 2 and 4, electric field mitigating shields 8 and 9 are provided, respectively. The gas insulated disconnecting switch having such a structure can be represented by a circuit diagram as shown in FIG.

In a steady state, the movable contactor 1B contacts the fixed contactor 1A and the current collector 3A, and a gas space exists between the arc discharge electrode 7 and the main circuit current. Circuit conductor 2 ... current collector 3A ... movable contact 1B ... current collectors 3B, 3C ... flow through current path of main circuit conductor 4,
It is not shunted to the resistor 5. In this way, since the main circuit current does not flow through the resistor 5 in the steady state, heat generation of the resistor 5 and magnetic saturation of the magnetic substance 6 do not pose a problem.

When an opening command is given to an operating device (not shown), the movable contact 1B is driven to the right in the figure and is first separated from the current collector 3A, and then the current is applied to the fixed contact 1A. Will flow to the movable contactor 1B via. When the separating operation further progresses, the movable contact 1B
Is separated from the fixed contactor 1A, and the arc 20 is re-ignited between the movable contactor 1B and the arc discharge electrode 7 this time. A surge occurs due to this re-ignition, but at this time, the current is different from the above-mentioned current path, and the main circuit conductor 2 ... Resistor 5 ... Conductor 7A ... Arc discharge electrode 7 ... Arc 20 ... Movable Contactor 1B ... Current collectors 3B, 3C ... Flows in the current path of the main circuit conductor 4, the current value is reduced by the resistor 5, and the surge is absorbed by the magnetic substance 6 which is not saturated by the reduced current. To be done.
Since the resistor 5 and the magnetic body 6 are effectively combined in this way for suppressing the surge, the axial length of the resistor 5 can be reduced and the charging current at the time of re-ignition can be reduced by the resistor 5. It is possible to suppress the surge well while suppressing the magnetic saturation of the magnetic body 6.

FIG. 3 is a vertical sectional front view of a gas-insulated disconnector as a gas-insulated switchgear according to another embodiment of the present invention.
Only the points of difference from the embodiment shown in will be described, and other equivalent parts will be denoted by the same reference numerals and detailed description thereof will be omitted.
The resistor 5 arranged on the outer periphery of the current collector 3A has one end fixed to the main circuit conductor 2 and electrically connected thereto, and the other end directly fixed to the arc discharge electrode 7. As in the previous embodiment, a plurality of resistors 5 are provided between the main circuit conductor 2 and the arc discharge electrode 7 so as to be electrically parallel to each other. On the other hand, as can be seen from FIG. 4 which is a circuit diagram, the magnetic body 6 is arranged so as to surround the outer peripheral portion of each of the resistors 5.

As described above, the resistor 5 and the magnetic body 6 are overlapped in the axial direction, and the magnetic body 6 is juxtaposed so as to surround the resistor 5, so that the arc discharge electrode is more than the case of the previous embodiment. It is possible to suppress the length of the protruding portion 7 of the fixed contactor 1A from the opposite-side tip end portion, and it is possible to further reduce the axial length as a whole. Also in this embodiment, since the charging current flows through the resistor 5 for the first time by re-ignition, there is no normal heat generation, and the surge is suppressed by the combination of the resistor 5 and the magnetic body 6 as in the previous embodiment. The effect can be obtained.

FIG. 5 is a vertical sectional front view of a gas insulation disconnector according to another embodiment of the present invention. In the embodiment shown in FIG. 3, the magnetic body 6 is arranged on the outer peripheral portion of the resistor 5,
Here, the magnetic body 6 is moved to the movable contact 1B side, and the current collector 3
It is arranged so as to surround B. The circuit diagram at this time is as shown in FIG. Generally, the movable contact 1B side is
An electric field mitigating shield 9 is provided to alleviate the electric field at the tip of the movable contactor 1B on the opposite side, but the inside thereof is a gas space. Therefore, when the magnetic body 6 is arranged so as to surround the current collector 3B in the electric field mitigating shield 9, this gas space is effectively utilized and the axial length of the fixed contactor 1A side in the case of the previous embodiment. The size of the resistor 5 can be reduced to a smaller size as a whole, and good insulation between the right end of the resistor 5 and the current collector 3A can be maintained. Further, since the magnetic body 6 is arranged in the current passage through which the re-ignition flows through the resistor 5, the magnetic saturation due to the re-ignition charging current is prevented and the surge is effectively suppressed as in the previous embodiment. can do.

FIG. 7 is a vertical sectional front view of a gas-insulated disconnector according to still another embodiment of the present invention, in which only differences from the embodiment shown in FIG. And detailed description is omitted. The resistor 5 in this embodiment is located on the outer periphery of the current collector 3A, and
One end is fixed to the main circuit conductor 2 and the other end is projected toward the movable contact 1B to support the arc discharge electrode 7, while the magnetic body 6 is fixed to the main circuit conductor 2 on the fixed contact 1A side. Is provided so as to be surrounded and is disposed inside the electric field mitigating shield 8. Therefore, this circuit diagram becomes as shown in FIG. 8, and with such a configuration, it is possible to obtain substantially the same effect as that of the previous embodiment shown in FIG.

FIG. 9 is a vertical sectional front view of a gas-insulated disconnecting switch according to another embodiment of the present invention, and only differences from the embodiment shown in FIG. 5 will be described. The structure of the movable contactor 1B side is the same as that of FIG. 5, and the magnetic body 6 concentrically surrounding the current collectors 3B and 3C is arranged, while the fixed contactor 1A side surrounds the outer periphery of the current collector 3A. The new resistor 5 has one end fixed to the main circuit conductor 2 and a fixed contact 1A at the other end, except for the resistor provided in the main circuit conductor 2.

In a steady state, the movable contactor 1B moves to the left in the figure and contacts the current collector 3A and the fixed contactor 1A. Therefore, the main circuit current is the main circuit conductor 2 ...
Current collector 3A: movable contact 1B: current collectors 3B, 3C ...
... The current flows through the main circuit conductor 4 and is not shunted to the resistor 5. As described above, since the main circuit current does not flow through the resistor 5 in the steady state, the heat generation of the resistor 5 and the magnetic saturation of the magnetic substance 6 do not pose a problem as in the previous embodiment.

Here, when an opening command is given to an operating device (not shown), the movable contact 1B is driven to the right in the figure and is first separated from the current collector 3A, and when the opening operation further proceeds, The movable contact 1B re-ignites with the fixed contact 1A. Then, the current flows from the main circuit conductor 2 to the resistor 5
Also, the current flows to the movable contact 1B via the fixed contact 1A, the current value is reduced by the resistor 5, and the surge is absorbed by the magnetic body 6 which is not saturated by the reduced current. Since the resistor 5 and the magnetic substance 6 are effectively combined for suppressing the surge in this way, the axial length of the resistor 5 can be reduced as in the previous embodiment, and at the time of re-ignition. The charge can be suppressed by the resistor 5 to prevent magnetic saturation of the magnetic body 6, and the surge can be suppressed well.

FIG. 10 is a vertical sectional front view of a gas insulation disconnector according to another embodiment of the present invention. In the embodiment shown in FIGS. 1 to 8 above, the arc discharge electrode 7 provided in the current path having the resistor 5 is arranged in a non-contact state with the movable contact 1B. The difference is that the discharge electrode 7 and the movable contact 1B are arranged so as to be in contact with each other. That is, the arc discharge electrode 7 is fixed to the other end of the resistor 5 whose one end is connected to the main circuit conductor 2 on the outer peripheral portion of the fixed contactor 1A, and the main circuit conductors 2 located before and after this resistor 5 are fixed. The inner surfaces of the cylindrical portion 2A, the resistor 5, and the arc discharge electrode 7 are continuously formed flat in the moving direction of the movable contact 1B. A magnetic body 6 is provided around the outer periphery of the resistor 5 so as to surround them, and an electric field mitigating shield 11 is fixed to the tip of the magnetic body 6 on the side of the movable contact 1B. On the other hand, the movable contactor 1B is in contact with the fixed contactor 1A so as to be in slidable contact with the inner surfaces of the cylindrical portion 2A, the resistor 5 and the arc discharge electrode 7 described above, in addition to the facing contact. The part 10 is attached. In the steady closed state, the movable contactor 1B is the fixed contactor 1B.
Since the contact portion 10 is in contact with A, and the contact portion 10 is in contact with the tubular portion 2A, the main circuit current is the main circuit conductor 2 ... the tubular portion 2A.
... Contact part 10 ... movable contact 1B ... current collectors 3B, 3C
The current flows through the main circuit conductor 4 and is not shunted to the resistor 5. As described above, since the main circuit current does not flow through the resistor 5 in the steady state, the heat generation of the resistor 5 and the magnetic saturation of the magnetic substance 6 do not pose a problem as in the previous embodiment.

When an opening command is given to an operating device (not shown), the movable contact 1B is driven to the right in the figure,
First, the contact portion 10 of the movable contactor 1B comes into contact with the resistor 5 after passing through the tubular portion 2A, so that the current flows to the movable contactor 1B via the fixed contactor 1A. When the separating operation further progresses, the movable contact 1B is separated from the fixed contact 1A, and this time, the main circuit conductor 2 ...
Cylindrical portion 2A ... Resistor 5 ... Arc discharge electrode 7 ... Contact portion 10 ... Flows to the movable contact 1B, and then the contact portion 10 separates from the arc discharge electrode 7 to move the movable contact 1B and the arc. The arc is re-ignited between the discharge electrodes 7. A surge is generated by this re-ignition, but at this time, the current is the main circuit conductor 2, the cylindrical portion 2A, the resistor 5, the arc discharge electrode 7, the arc, the movable contact 1B, and the collector. Electronic 3B, 3
C ... The current value flows through the current path of the main circuit conductor 4, the current value is reduced by the resistor 5, and the surge is absorbed by the magnetic substance 6 which is not saturated by the reduced current. Also in this embodiment, since the resistor 5 and the magnetic substance 6 are effectively combined for suppressing the surge in this way, the axial length of the resistor 5 can be reduced and the charging current at the time of re-ignition can be reduced. Is suppressed by the resistor 5 and the magnetic substance 6
It is possible to excellently suppress the surge while preventing the magnetic saturation.

The arrangement in which the arc discharge electrode 7 and the movable contact 1B are arranged to contact each other as in the embodiment shown in FIG. 10 is also adopted in the embodiments shown in FIGS. 3 to 9. be able to. Further, in each of the above-described embodiments, the gas-insulated switchgear is exemplified as the gas-insulated switchgear, but the same can be applied to a grounding switch in which the movable contact is brought into contact with the fixed contact of the main circuit conductor to ground it. ..

[0021]

As described above, according to the present invention, the resistor 5 reduces the current value, and the surge is absorbed by the magnetic substance which is not saturated by the reduced current. And the magnetic body 6 are effectively combined, the axial length of the resistor 5 can be reduced, and the charging current at the time of re-ignition is suppressed by the resistor 5 to prevent magnetic saturation of the magnetic body 6. However, the surge can be suppressed well.

[Brief description of drawings]

FIG. 1 is a vertical sectional front view showing a main part of a gas-insulated switchgear according to an embodiment of the present invention.

FIG. 2 is a circuit diagram of the gas-insulated switchgear shown in FIG.

FIG. 3 is a vertical sectional front view of a gas insulated switchgear according to another embodiment of the present invention.

FIG. 4 is a circuit diagram of the gas-insulated switchgear shown in FIG.

FIG. 5 is a vertical sectional front view of a gas-insulated switchgear according to still another embodiment of the present invention.

6 is a circuit diagram of the gas-insulated switchgear shown in FIG.

FIG. 7 is a vertical sectional front view of a gas insulated switchgear according to still another embodiment of the present invention.

8 is a circuit diagram of the gas-insulated switchgear shown in FIG.

FIG. 9 is a vertical sectional front view of a gas insulated switchgear according to still another embodiment of the present invention.

FIG. 10 is a vertical sectional front view of a gas insulated switchgear according to still another embodiment of the present invention.

[Explanation of reference symbols] 1A fixed contactor 1B movable contactor 2 main circuit conductors 3A to 3C current collector 4 main circuit conductor 5 resistor 6 magnetic body 7 arc discharge electrode

Claims (5)

[Claims] 1. A fixed contact provided on a main circuit conductor, a movable contact coming in contact with and separated from the fixed contact, and a resistor provided in a current path through which a current flows only when the movable contact is opened and closed. In a gas-insulated switchgear equipped with a magnetic body, a magnetic body is arranged so as to surround a current passage through which a current flows during opening and closing, and magnetic saturation of the magnetic body is achieved by the resistor provided in the current passage through which a current flows only during the opening and closing operation. The gas-insulated switchgear is characterized in that 2. The device according to claim 1, wherein the fixed contact and the movable contact are provided on substantially the same straight line.
Gas insulation characterized in that the resistor is arranged on an outer peripheral portion of the fixed contact, and an arc discharge electrode arranged via a gap with the movable contact is connected to the movable contact side of the resistor. Switchgear. 3. The device according to claim 1, wherein the fixed contact and the movable contact are provided on substantially the same straight line,
A plurality of the resistors are juxtaposed on the outer periphery of the fixed contact,
It is characterized in that an arc discharge electrode arranged with a gap with the movable contact is connected to the movable contact side of each of the resistors, and the magnetic body is provided on an outer peripheral portion of each of the resistors. Gas insulated switchgear. 4. The electric field relaxation shield according to claim 1, further comprising an electric field relaxation shield for relaxing an electric field at a tip portion of the movable contact, and the magnetic body is arranged in the electric field relaxation shield. Gas insulated switchgear. 5. The device according to claim 1, wherein the fixed contact and the movable contact are provided on substantially the same straight line,
On the outer peripheral portion of the fixed contact, an arc discharge electrode is connected to the movable contactor side other end of the resistor whose one end is connected to the main circuit conductor, and the movable contactor is connected to the fixed contactor. A gas-insulated switchgear comprising a contact portion slidably contacting the arc discharge electrode so as to separate from the arc discharge electrode after the break.