JPH03155327A - Device for detecting inner fault - Google Patents

Abstract

PURPOSE:To improve a reliability of detecting the inner situation of a body to be detected continuously with high accuracy and to prevent erroneous operations by monitoring the inner situation of the body to be detected electrically via an optical means. CONSTITUTION:A detection container 7 and a bellows 5 are provided on a gas container 6 of a compressed gas insulation switching device being a body to be detected. A frame body 5a of the bellows 5 is fixed on the gas container 6. A device 1 for projecting a laser beam is mounted on the frame body 5a and is fixed so as to irradiate an expansion part 5b of the bellows 5. A mirror 2 is fixed on the expansion part 5b and irradiates a beam receiving means 3. When the temperature in the gas container 6 rises due to a failure generated in the compressed gas insulation switching device, the bellows perform a telescopic action. The beam receiving means 3 detects the telescopic action as an electric signal. Thereby, since no mechanical contact is used, a reliability can be improved preventing erroneous operations.

Description

[Detailed Description of the Invention] [Industrial Field of Application] The present invention relates to an internal failure detection device for detecting accidents such as ground faults and phase-to-phase short circuits that occur inside sealed power equipment such as gas-insulated switchgear. .

BACKGROUND ART FIG. 4 shows an example in which an internal failure detection device 50 disclosed in Japanese Unexamined Patent Publication No. 58-115370 is attached to a gas insulated switchgear 100. In the figure, an insulating gas is sealed in an internal space 9 of a closed container 6 of a gas-insulated switchgear 100, and a high-voltage circuit conductor 33 is enclosed therein. This high-voltage electrical circuit conductor 33 is supported inside the closed container 6 via an insulator. The display device 32 receives an electrical signal from the internal failure detection device 50 and displays information on this signal. FIG. 5 is a sectional view of the internal failure detection device 50 of FIG. 4. This internal failure detection device 50 is configured so that the bellows 5 expands and contracts in response to a sudden change in pressure inside the gas insulated switchgear 100, which is the object to be detected, and the contacts of the microswitch 31 open and close.

The operation of the conventional internal failure detection device 50 will be explained. When an accident such as a ground fault or a short circuit between phases occurs inside the gas insulated switchgear 100, the temperature of the internal space 9 rises rapidly due to arc energy or the like. As the temperature rises, the gas pressure in the internal space 9 increases, and the bellows 5 communicating with this space is expanded. The internal contacts of the microswitch 31 interlocked with the bellows 5 are closed by the extension of the bellows 5, and the display device 32, which is electrically connected to the internal contacts, is exposed to pressure rising inside the gas-insulated switchgear 100. Display what has been done.

[Problems to be Solved by the Invention] As described above, the conventional internal failure detection device uses a microswitch to detect the state of the detected object, so
There were problems in terms of the amount of information and accuracy in that only two states (quiet) could be displayed, and in terms of reliability, such as the microswitch malfunctioning due to noise caused by discharges generated outside this power equipment. .

The present invention has been made to solve the above-mentioned problems, and provides a highly reliable internal failure detection device that can continuously detect the internal state of a detected object with high accuracy and that does not cause malfunctions. The purpose is to

[Means for Solving the Problems] An internal failure detection device according to the present invention includes: a gas container in which a high voltage member is installed in a sealed gas space; a pressure detection means communicating with the gas container; The apparatus includes a reflecting means attached to a movable part of the means, a light emitting means for projecting light onto the reflecting means, and a light receiving means for receiving light from the reflecting means.

[Effect] If an accident such as a ground fault or mutual short circuit occurs in the high voltage components inside the sealed gas container, which is the object to be detected, the temperature inside the gas container will rise rapidly due to the arc generated by this accident. . As the temperature rises, the pressure inside the gas container increases, and the pressure detection means, such as a bellows, communicating with the gas container expands. A reflecting means, such as a mirror, is attached to the telescopic portion of the bellows.
The light receiving means is constantly irradiated by reflecting the light from the light emitting means. Therefore, the extension or contraction operation of the bellows is continuously detected by the light receiving means.

[Embodiment] Hereinafter, one embodiment of the internal failure detection device 50 of the present invention will be described with reference to the drawings. FIG. 1 is a sectional view of an internal failure detection device 50 showing one embodiment of the present invention, FIG. 2 is an operational explanatory diagram showing the main parts of FIG. 1, and FIG. 3 is a bellows 50 of this embodiment
FIG. 2 is a relationship diagram showing the relationship between the amount of variation and time, and the light receiving position in the light receiving means 3 at that time.

In FIG. 1, a gas insulated switchgear 10 which is an object to be detected
A detection container 7 is fixed to the gas container 6 of No. 0. Inside the detection container 7, a bellows 5 serving as a pressure detection means is disposed in communication with the gas container 6. This bellows 5 is composed of a frame body 5a and a telescopic portion 5b, and the frame body 5a is fixed to a gas container 6. As shown in FIG. 1, a light emitting means, such as a laser beam irradiation device, is attached to the frame 5a of the bellows 5, and is fixed so as to irradiate the extensible portion 5b of the bellows 5. A reflecting means, for example a mirror 2, is fixed to the extendable portion 5b that is irradiated with this light, and refracts the incident light at right angles. The refracted light is transmitted to the light receiving means 3 fixed to the frame 5a of the bellows 5.
irradiate. The light-receiving means 3 has a light-receiving section 4 in which a plurality of light-receiving elements, for example, phototransistors 4°, 4°, . None). As shown in FIG. 2, this plurality of phototransistors 4°.

4°... are arranged in a direction parallel to the expansion/contraction direction of the expansion/contraction portion 5b of the bellows 5.

Next, the operation of the above embodiment of the present invention shown in FIG. 1 will be explained. When an accident such as a ground fault or a short circuit between phases occurs inside the gas insulated switchgear 100, the temperature inside the gas container 6 rises rapidly due to an arc generated in the accident area. Along with this temperature rise, the pressure inside this gas container 6 also rises rapidly once, and then unless energy is reinjected due to an accident such as an arc, the pressure inside this gas container 6 will return to the state before the accident. .

If an accident occurs in the gas insulated switchgear as described above, the pressure inside the gas container 6 will change rapidly.
The telescopic portion 5b of the bellows 5 communicating with the gas container 6 is moved by the telescopic action. A mirror 2 is fixed to the extendable portion 5b, and the mirror 2 reflects the light from the laser beam irradiation device 1 toward the light receiving portion 4 of the light receiving means 3. Therefore, the position of the light receiving point of the light incident on the light receiving section 4 moves in the direction of the expansion and contraction operation according to the expansion and contraction operation of the expansion and contraction section 5b.

The movement of this light is caused by a plurality of light receiving elements provided in the light receiving section 4 in parallel with the expansion/contraction direction, such as a phototransistor 4',
4'... are sequentially received and detected as electrical signals. Movement of the telescopic portion 5b of the bellows 5 after the accident occurs;
FIG. 3 shows the temporal changes in light received by each light receiving element at that time. As is clear from FIG. 3, by using more light-receiving elements per unit length, it is possible to know the accident situation in the detected object in more detail.

Further, the internal failure detection device 50 of the present invention includes a bellows 5.
The mirror 2 and the light-receiving section 4 may be provided with a known position adjusting means so as to be able to cope with movement or twisting caused by time or subsequent aging when attached to the telescopic section 5b.

In this way, when the above-mentioned accident occurs inside the gas-insulated switchgear 100, the internal failure detection device 50
detects these accidents as electrical signals,
By transmitting this electrical signal to a display position provided outside, it is possible to centrally monitor objects to be detected at multiple locations. Further, according to the internal failure detection device of the present invention, it is possible to estimate the scale of the accident in the detected object from the light receiving position of the light receiving means.

Although the above embodiment detects an accident involving a high-voltage member of the gas-insulated switchgear 100, it is also possible to detect an accident caused by a sudden change in temperature or pressure in a sealed space as an object to be detected. The invention can also be used in other devices that occur from time to time.

[Effects of the Invention] As described above, since the internal failure detection device of the present invention electrically monitors the internal state of the detected object through optical means, it is possible to accurately detect accidents that occur in the detected object. It can detect continuously at high speeds, and because it does not use mechanical contacts such as microswitches, it is a highly reliable device that does not cause malfunctions.

[Brief explanation of the drawing]

FIG. 1 is a sectional view showing an embodiment of the internal failure detection device of the present invention, FIG. 2 is an operation explanatory diagram showing the main parts of FIG. 1, and FIG. 3 is a detection means of the embodiment of FIG. 1. Figure 4 is a schematic cross-sectional view of a conventional internal failure detection device installed in a gas-insulated switchgear, and Figure 5 is a cross-sectional view of a conventional internal failure detection device. be. In the figure, 1 is a light emitting means, 2 is a reflecting means, 3 is a light receiving means, 5 is a pressure detecting means, and 6 is a gas container. In addition, in the figures, the same reference numerals indicate the same or corresponding parts.

Claims (1)

[Claims] (1) A gas container with a high voltage member installed in a sealed gas space, a pressure detection means communicating with the gas container, a reflection means attached to a movable part of the pressure detection means, and projecting light onto the reflection means. An internal failure detection device comprising: a light emitting means; a light receiving means for receiving light from the reflecting means.