JPH05300617A - Gas insulated switching apparatus - Google Patents

Abstract

PURPOSE:To improve safety by a method wherein, when a surge sensor or a voltmeter detects an abnormal surge during the opening/closing operation of a circuit breaker or a disconnector, the circuit breaker or the disconnector which performs the opening/closing operation is displayed and, further, an alarm is raised. CONSTITUTION:If an arc generated by a restrike, etc., is transmitted through a resistor during the opening/closing operation of a circuit breaker or a disconnector, a high voltage is applied to the resistor and a large current flows. If a surge sensor 22 detects the abnormal surge at that time, an abnormal surge detection signal is transmitted to a microcomputer 25 and the microcomputer 25 operates a display means and an alarm means. The display means displays the circuit breaker or the disconnector which performs the opening/ closing operation and the alarm means gives an alarm. With this constitution, the defect of the resistor attached to the circuit breaker or the disconnector can be detected in an early stage and the dielectric breakdown of a gas insulated apparatus caused by the repeated use of the resistor can be avoided and the safety can be improved.

Description

Detailed Description of the Invention

[0001]

The present invention relates to an S container in a sealed container.
The present invention relates to a gas-insulated switchgear for filling an arc-extinguishing gas such as F ₆ gas, in particular, having a circuit breaker or a disconnector to which a resistor is attached, and the arc generated by re-ignition at the time of opening and closing the circuit is the resistance. The present invention relates to a gas-insulated switchgear adapted to flow through the body.

[0002]

2. Description of the Related Art Generally, a gas-insulated switchgear is used in a substation or switchgear, and is equipped with a metal cylindrical container,
This is a switchgear which is filled with an arc-extinguishing gas such as SF ₆ gas, and insulatively supports contacts for opening and closing high voltage conductors and currents using insulating spacers and the like. Here, FIG. 2 illustrates a single wire connection diagram of a general substation, and FIG. 3 illustrates an example of a gas insulated switchgear of the line circuit.
The gas-insulated switchgear of FIG. 3 has a circuit breaker 1 and a disconnector 2. In the figure, 3 is a grounding switch, 4 is a lightning arrester,
5 is a bushing.

Such a gas-insulated switchgear is excellent in economic efficiency and maintainability, and in recent years, it has become the mainstream of switchgear. Recently, a gas-insulated switchgear has been proposed in which a resistor 6 is attached to the circuit breaker 1 or the disconnector 2 in order to suppress surges that occur during switching. FIG. 4 shows a structural diagram of the disconnector to which the resistor is attached.

That is, the tank 10 is provided below the disconnector 2.
Is provided, and the ground switch 3 and the insulating spacer 9 are installed on the side surface of the tank 10. Insulating cylinders 11 and 11 are supported facing each other on the upper end side and the lower end side in the tank 10, and the movable contactor 8 and the fixed side contact portion 13 are supported by the insulating cylinders 11 and 11 from above and below. It is provided. The fixed side contact portion 13 has a resistor 6 and an insulating rod 7.
Has one end attached and fixed. Also, the resistor 6
A resistor shield 12 is attached to the other end of the insulating rod 7 with a movable contact 8 and a gap 15.

In the disconnector 2 as described above, the circuit breaker 1
A phenomenon in the case of opening a short pipe line up to is described with reference to FIG. That is, the movable contact 8 has the fixed-side contact portion 13
When the power supply side voltage 16 is opened, the load side voltage 16 (voltage on the pipeline side to be opened) holds the voltage at the time of opening, and the power supply side voltage 17 changes from the voltage at the time of opening. Therefore, a voltage appears between the poles of the disconnector 2, and the re-ignition 18 occurs. At this time, a surge 26 occurs and a surge current flows. However, this surge current immediately decays and the arc is extinguished.

Then, the voltage at that time remains on the load side, and a voltage difference between the load side voltage 16 and the power source side voltage 17 appears between the poles of the disconnector 2. At the same time, the movable contact 8 also continues to be separated from the fixed-side contact portion 13, so that the withstand voltage between the poles is re-ignited with a greater inter-electrode voltage than the previous re-ignition 18. Such re-ignition is repeated several times, and when the movable contact 8 is sufficiently separated and the inter-electrode dielectric strength exceeds the voltage applied between the electrodes, the interruption is completed.

In the disconnector 2 as described above, a surge 26 is generated each time re-ignition occurs, but since the resistor 6 is attached, the re-ignition causes the movable contact 8 and the resistor shield 12.
And a restriking current flows through the resistor 6. Therefore, the resistor 6 can suppress the surge.

Also, when closing a short conduit to the circuit breaker 1, a pre-arc is generated between the movable contact 8 and the resistor shield 12 as in the above-mentioned opening, and a surge current is generated in the resistor 6. Therefore, the resistor 6 can suppress the surge. There is known a gas-insulated switchgear in which a resistor is attached to a circuit breaker as well as a disconnector to suppress a surge.

[0009]

By the way, although the resistor 6 is manufactured with a sufficient margin, in the event that a defect such as disconnection or breakage occurs in the resistor 6, the resistor 6 is to be manufactured. Dielectric breakdown occurs on or near the surface. The resistor 6 in which the insulation breakdown has occurred cannot sufficiently suppress the surge generated during the opening / closing operation, and the surge occurs in the gas-insulated switchgear, which threatens the insulation of the gas-insulated switchgear.

Further, when the resistor is repeatedly used in a state where a malfunction occurs, the resistor breaks, and the fragments are scattered inside the breaker or disconnector, resulting in dielectric breakdown inside the breaker or disconnector. There has occurred. Moreover, there is a possibility that the dielectric breakdown of the gas-insulated switchgear itself may occur due to the application of a large surge many times.

The present invention has been proposed in order to solve the above-mentioned problems of the prior art. The object of the present invention is to detect a defect of the resistor at an early stage and cause a problem. It is an object of the present invention to provide a gas-insulated switchgear with improved safety by preventing dielectric breakdown of the gas-insulated switchgear due to repeated use of resistors.

[0012]

In order to achieve the above object, a gas-insulated closing device according to claim 1 of the present invention has a circuit breaker or a disconnector to which a resistor is attached, and a surge sensor is provided at various places. Or, when a voltage measuring device is attached and the surge sensor or voltage measuring device detects an abnormal surge that does not occur if the resistor is sound during opening / closing operation of the circuit breaker or disconnecting switch,
It is characterized in that the circuit breaker or the disconnecting switch that has performed the opening / closing operation is displayed and an alarm is issued.

According to a second aspect of the present invention, in the gas-insulated closing device, when the surge sensor or the voltage measuring device detects the abnormal surge during opening / closing operation of a circuit breaker or a disconnector,
It is characterized in that the circuit breaker or the disconnecting switch that has performed the opening / closing operation is displayed, an alarm is issued, and the operation of the circuit breaker or the disconnecting switch is locked.

Further, the gas-insulated closing device according to claim 3 of the present invention is characterized in that a corona sensor is attached in combination with the surge sensor or the voltage measuring device.

[0015]

In the present invention having the above structure,
The arc generated by re-ignition or the like during the opening / closing operation of the circuit breaker or the disconnector passes through the resistor, a large voltage is applied to the resistor, and a large current flows. At that time, if a surge sensor or voltage measuring device attached to each place in the gas insulated switchgear detects an abnormal surge that does not occur if the resistor is sound, it displays the circuit breaker or disconnector that performed the switching operation. And give an alarm. As a result, it is possible to detect early that a failure has occurred in the resistor attached to the circuit breaker or the disconnector.

Although a lightning surge exists as an abnormal surge, the surge sensor or voltage measuring device of the present invention is
Since the abnormal surge is detected under the condition that the circuit breaker or the disconnector is being opened / closed, the lightning surge is not detected as the abnormal surge. Therefore, in the present invention, it is possible to accurately find a circuit breaker or a disconnector having a defective resistor.

According to the present invention of claim 2, when the surge sensor or the voltage measuring device detects an abnormal surge in the circuit breaker or the disconnector, the operation lock of the circuit breaker or the disconnector is performed. It is possible to more reliably prevent the dielectric breakdown of the gas insulated switchgear without repeatedly using the resistor in the defective state.

Further, according to the present invention of claim 3, by using the corona sensor, it is possible to detect the corona caused by the defect of the resistor. Therefore, it is possible to detect the defective resistor before the abnormal surge occurs, and it is possible to detect the defective resistor at an early stage.

[0019]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the gas-insulated switchgear according to the present invention will be specifically described below with reference to FIG. The present embodiment is a gas-insulated switchgear adapted to the single-line connection diagram of FIG. 2, and basically has a circuit breaker and a disconnector to which a resistor is attached. The arc generated by ignition or the like flows through the resistor to suppress the surge.

The present embodiment is an invention corresponding to Claims 2 and 3, and a surge sensor 22 as shown in FIG. 1 is provided as a feature according to the present invention. In FIG. 1, 19 is a conductor, 20 is an insulating spacer, and 21 is a tank. The surge sensor 22 is composed of an E / O converter and is embedded on the low-voltage side of the insulating spacer 20. The surge sensor 22 detects an abnormal surge, and outputs the abnormal surge detection signal to the O / E converter 24 via the optical fiber 23. The O / E converter 24 is connected to the microcomputer 25 and outputs an abnormal surge detection signal to the microcomputer 25. The micro computer 25 is a display means (not shown) for displaying a desired breaker or disconnector,
And an alarm means (not shown). Further, the microcomputer 25 is adapted to lock the operation of the circuit breaker or the disconnector. Further, the surge sensor 22 can also monitor the corona at all times, and sends the monitored result as a signal to the microcomputer 25.

In the gas-insulated switchgear, the operations that cause a large surge in the circuit breaker are:
The operation of closing the busbar is a case where a large surge occurs in the disconnector, and the operation of opening and closing a short pipeline to the circuit breaker. Therefore, if a failure occurs in the resistor and dielectric breakdown occurs, surges occur in both sides of the circuit breaker and both sides of the disconnector. Therefore, one or more surge sensors 22 as described above are attached to the line side of the circuit breaker, the transformer side, and each bus bar in each line.

The operation of this embodiment having the above construction is as follows. That is, when the arc generated by re-ignition or the like during the opening / closing operation of the circuit breaker or the disconnector passes through the resistor, a large voltage is applied to the resistor and a large current flows. At that time, if the surge sensor 22 detects an abnormal surge, an abnormal surge detection signal is sent to the microcomputer 2
5, the microcomputer 25 operates the display means (not shown) and the alarm means (not shown).

Therefore, the display means (not shown) displays the circuit breaker or the disconnector which has been opened and closed, and the alarm means (not shown) gives an alarm. This makes it possible to detect early that a failure has occurred in the resistor attached to the circuit breaker or the disconnector. When the surge sensor 22 detects an abnormal surge in the circuit breaker or the disconnector, the microcomputer 25 can lock the circuit breaker or the disconnector. Therefore, according to such an embodiment, it is possible to prevent the defective resistor from being repeatedly used, and it is possible to reliably prevent the dielectric breakdown of the gas insulated switchgear and improve the safety. Furthermore, in the present embodiment, the condition that the surge sensor 22 detects the abnormal surge is set such that the circuit breaker or the disconnector is in the opening / closing operation, so that the lightning surge is not erroneously recognized as the abnormal surge. It is possible to accurately find only the resistor in which a defect has occurred.

The present invention is not limited to the above-described embodiment, but a voltage measuring device may be used instead of the surge sensor, and if a resistor is attached, a circuit breaker or It may be a gas-insulated switchgear having either one of the disconnectors.

Further, the mounting location and the number of the surge sensor or the voltage measuring device can be appropriately selected. For example, although the surge sensor or the voltage measuring device is mounted on the low-voltage side of the insulating spacer 20 in the above-described embodiment, the surge impedance in a state close to the load side, the open end, or the open end of the circuit breaker or the disconnector. Can be limited to such a place (for example, where the surge impedance increases from about 70Ω to about 350Ω in the overhead line from the gas insulated switchgear). It is known that a large surge is likely to occur at these locations, and therefore the detection sensitivity for abnormal surge can be increased. Further, if a plurality of surge sensors or voltage measuring devices are attached, the abnormal surge is not overlooked and the detection accuracy is improved.

Further, in order to prevent the lightning surge from being mistakenly recognized as an abnormal surge, the condition under which the surge sensor or the voltage measuring device detects the abnormal surge is that "the circuit breaker or the disconnector is in the opening / closing operation". Although set, shortening the "opening / closing operation" period of the circuit breaker or disconnector reduces the possibility of falsely recognizing a lightning surge as an abnormal surge. Further, as for the circuit breaker, since there is no re-ignition at the time of opening, it is possible to set only the condition of "closed".

Further, for the disconnector, like the electric spring operation, 2-3 seconds after the operation command is the time for the drive spring to be energized. Therefore, this time can be excluded from the "opening / closing" period, which makes it possible to shorten the "opening / closing operation" period and reduce the possibility of falsely recognizing a lightning surge as an abnormal surge. .

[0028]

As described above, according to the gas-insulated switchgear of the present invention, the surge sensor or the voltage measuring device attached to each part of the device causes an abnormal surge during the opening / closing operation of the circuit breaker or the disconnector. When detecting, it is possible to display the circuit breaker or disconnector that has performed the opening and closing operation and to issue an alarm,
We were able to detect defects in the resistor at an early stage, prevent the breakdown of the gas-insulated switchgear caused by repeated use of the defective resistor, and improve safety.

[Brief description of drawings]

FIG. 1 is an explanatory diagram showing the configuration of a surge sensor used in a gas-insulated switchgear according to the present invention.

[Fig. 2] Single line connection diagram of a general substation

FIG. 3 is a layout drawing showing the configuration of a gas-insulated switchgear for the line circuit of FIG.

FIG. 4 is a sectional view showing a configuration of a disconnector to which a resistor is attached.

5 is an explanatory view for explaining a phenomenon in the case of opening a short pipeline with the disconnector of FIG.

[Explanation of symbols]

 19 conductor 20 insulating spacer 21 tank 22 surge sensor 23 optical fiber 24 O / E converter 25 micro computer

Claims (3)

[Claims] 1. An arc which is generated by re-ignition at the time of opening and closing the circuit is provided with a circuit breaker or a disconnector, which is filled with an arc-extinguishing gas in a hermetically sealed container and to which a resistor is attached. In a gas-insulated switchgear that is made to flow through the body, a surge sensor or voltage measuring device is attached to each location, and if the surge sensor or voltage measuring device has a sound resistor during opening / closing operation of the circuit breaker or disconnector. A gas-insulated switchgear, characterized in that, when an abnormal surge that does not occur is detected, the circuit breaker or disconnector that has been opened and closed is displayed and an alarm is issued. 2. When the surge sensor or the voltage measuring device detects the abnormal surge during the opening / closing operation of the circuit breaker or the disconnecting switch, the circuit breaker or the disconnecting switch that has performed the opening / closing operation is displayed,
The gas insulated switchgear according to claim 1, wherein an alarm is issued and the operation of the circuit breaker or the disconnector is locked. 3. The gas-insulated switchgear according to claim 1, further comprising a corona sensor attached to the surge sensor or the voltage measuring device.