JPH02158029A - Vacuum reduction detecting device for vacuum interrupter - Google Patents

Abstract

PURPOSE:To detect a reduction in degree of vacuum of a vacuum interrupter in a position separated from the vacuum interrupter by leading a discharge light generated at the time of reducing the degree of vacuum of the vacuum interrupter received in a gas insulating equipment to the outside of the equipment by means of a fluorescent resin material and a linear fluorescent resin member. CONSTITUTION:When a discharge is generated in a vessel, the discharge light is released from the cut of the shield of the vacuum vessel to the inside of an earthing tank 1. This released light is detected by cylindrical fluorescent resin members 18, 18 and converted into a fluorescent light, which is transmitted to linear fluorescent resin members 19, 19, injected to optical fibers 20, 20, and further supplied to the terminal A of a detector 21. On obtaining the received light, the detector 21 sends a signal to a break instruction part 22. Hence, even when the discharge light is detected by the fluorescent resin member and the resulting light is converted into the fluorescent light and inputted into the optical fiber, no attenuation is caused in the optical fiber, and the reduction in degree of vacuum can certainly be detected.

Description

DETAILED DESCRIPTION OF THE INVENTION A. Field of Industrial Application This invention relates to a device for detecting a decrease in the degree of vacuum of a vacuum interrupter in a gas insulated device housing a vacuum interrupter therein.

B4 Summary of the Invention This invention provides a vacuum interrupter detection device for detecting a decrease in vacuum level, which includes: a cylindrical fluorescent resin member installed inside the device; A linear fluorescent resin member attached to a cut-off part of this member is used to lead it outside the device, making it possible to detect a decrease in the degree of vacuum at a location away from the vacuum interrupter. .

C0 Conventional Technology Vacuum interrupters inherently have a longer life both electrically and mechanically than other switching devices, and require almost no maintenance or inspection. However, in addition to a decrease in the degree of vacuum due to an increase in the number of shut-offs, the degree of vacuum may decrease due to vacuum leakage from bellows, airtight joints, etc., although this is very rare. The vacuum interrupter (7r1 flow breaker) has a reduced degree of vacuum, resulting in a decrease in its interrupting performance as a vacuum breaker, and eventually becomes unable to interrupt. Therefore, it is required to periodically or constantly check the degree of vacuum. However, after the vacuum interrupter is assembled with an operating mechanism to form a vacuum breaker, it is desired that the degree of vacuum can be accurately and easily tested in the energized state.

In order to meet the above requirements, there is a vacuum level drop detection device for a vacuum interrupter described in Japanese Patent Laid-Open No. 62-43530. The invention described in the above publication provides a metal intermediate shield insulated from the electrode, and when the degree of vacuum decreases between the intermediate shield and one system potential member on either the fixed side or the movable side, A first vacuum gap that discharges in a vacuum area that can be cut off is formed, and the discharge light generated when discharging in the first vacuum gap is detected by a light receiving section provided on the outer periphery of the glass insulating cylinder, and a detector is connected to the optical fiber. When the detector detects discharge light from the first vacuum gap, a cutoff command is sent. When the degree of vacuum in the vacuum interrupter decreases during energization, discharge begins at the first vacuum gap (long gap) provided on either the fixed side or the movable side before reaching the uninterruptable area. . At this time, the second vacuum gap (similar gap)
In this case, no discharge occurs, and the second vacuum gap is not induced to discharge by the discharge in the first vacuum gap.

By discharging in the first vacuum gap, fluorescence or direct light from the cylinder due to the discharge is detected by a light receiving section and guided to a detector through an optical fiber. As a result, the detector immediately detects whether the degree of vacuum has decreased.

Since the detection is made when only the first vacuum gap is discharging, the current can be turned on or off by opening the electrodes immediately after the detection.

D1 Problems to be Solved by the Invention Since the discharge light generated in the glass insulating tube is generated locally, the discharge light may not enter the light receiving section when it is detected by the light receiving section and guided to the destination fiber.

In addition, a lens is usually attached to the light receiving part, and a method is used to condense the discharge light with the lens and introduce it into the optical fiber, but if the discharge does not occur within the range where the lens can receive the light, There is a problem that a large amount of discharge light cannot be introduced into the optical fiber. Furthermore, there is a problem that the discharge light is relatively easily attenuated within the optical fiber.

Especially if the vacuum interrupter is housed inside gas-insulated equipment,
The optical fiber must be pulled out to the outside of the device, and gas sealing problems may also occur.

SUMMARY OF THE INVENTION An object of the present invention is to provide a device for detecting a decrease in the degree of vacuum of a vacuum interrupter, which has a wide condensing area, reliably obtains multiple discharge light, and converts it into fluorescent light.

E1 Means for Solving the Problem This invention forms a vacuum container by closing both ends of a glass insulating cylinder with end plates, and a fixed electrode rod is hermetically introduced into the vacuum container from one end plate, and the other end is closed. A movable electrode rod that can approach and leave the fixed electrode rod is airtightly introduced from the plate through a bellows.
A pair of fixed and movable electrodes that can be brought into and out of contact with each other are provided at the inner ends of both electrode rods, and a metal intermediate shield that surrounds at least the outer periphery of the electrodes is insulated from the electrodes in the vacuum container. In a device for detecting a decrease in the degree of vacuum in a vacuum interrupter capable of freely opening and closing a system electrical circuit, the apparatus comprises: a gas insulated device housing the vacuum container; A cylindrical fluorescent resin member arranged so that the discharge light inside can be detected, and a linear fluorescent resin member inserted into the cut part by cutting a part of this cylindrical fluorescent resin member. Then, this linear fluorescent resin member is led out to the outside of the equipment along the inner wall of the gas-insulated equipment, and an optical fiber whose one end is optically coupled to the leading end, and a vacuum vessel connected to the other end of this optical fiber are connected to the optical fiber at one end. The detector is equipped with a detector that sends a cutoff command when it detects discharge light from the discharge light source.

21 Effect When a discharge occurs in the vacuum container and discharge light is generated, the source of the light is collected by a cylindrical fluorescent resin member installed on the inner wall of the device, and is introduced into the linear fluorescent resin member at the cut portion of the device. transmitted to an external optical fiber. Since the light beam incident on the optical fiber has been converted into fluorescent light, it reaches the detector without being attenuated within the optical fiber. This makes it possible to reliably issue a cutoff command, and by opening the electrodes, the current can be cut off.

G. Example The present invention will be described below based on embodiments shown in the drawings.

Fig. 1 shows a tank-type circuit breaker which is an example of gas insulated equipment. and supported by an insulating support insulator tube 4. Reference numeral 5 denotes an insulated operating ring, one end of which is connected to the movable lead rod of the vacuum interrupter 2, and the other end connected to the operating shaft 7 of the operating section 6. 8 is a pressure contact spring, and 9 is an operating lever.

10.11 is a bushing, one end of a conductor 12.13 inside the bushing 1011 is connected to the movable side and the fixed side of the vacuum interrupter 2, and the other end is connected to the main circuit terminal 14.15 on the upper part of the bushing 10.11. Ru. 16.17 is a bushing type current transformer.

18.18 is a cylindrical fluorescent resin member whose details are shown in Figures 2A and B, and this cylindrical fluorescent resin stamp material 18.18 is a grounding tank! The vacuum interrupter 2 and the vacuum interrupter 2 are coaxially attached to the inner wall of the vacuum interrupter 2. In particular, the fluorescent resin member 18.18 is provided at a position that matches the cut in the shield inside the vacuum container constituting the vacuum interrupter 2. Cylindrical fluorescent resin member 1
A cut portion is provided at 8.18, and a linear fluorescent resin member 19.19 extends from the cut portion along the inner wall of the grounded tank 1 in the left and right directions as shown in the drawing, and the tank! It is sealed and led out from the lids fa and lb of the.

The end of the led-out linear fluorescent member 19.19 is optically coupled to the tip fiber 20.20 and grounded to the detector 21.

Reference numeral 22 denotes a cutoff command section which operates based on the output of the detection section 21, and this cutoff command section 22 is supplied with a signal from the detection section 21 only when the degree of vacuum decreases in a vacuum region where shutoff is possible.

Incidentally, when the cutoff command section 22 receives the above-mentioned signal, it sends out a J%J report to notify that the degree of vacuum has decreased.

Next, according to FIG. 2A and B, a cylindrical fluorescent resin member 18.1
8 is acrylite (PMMA), polycarbonate (P
C) It is constructed using a cylindrical material made of transparent plastic such as boris dylene (PS) mixed with fluorescent dye, and both ends of the cylinder are coated with silver plating for reflection, and white and black 2.
Light is shielded by a multi-layered resin. A portion of the cylinder constructed in this manner is cut, and a portion of a linear fluorescent resin member 19, 19 is inserted into the cut portion 18a as shown in FIG. 2B. The linear fluorescent resin member 19.19 is arranged as shown in the grounded tank 1 of FIG. 1, and is configured so that a light beam is incident on an optical fiber 20.20 provided outside the tank.

Next, the operation of the above embodiment will be described.

Now, when a discharge occurs within the vacuum vessel, the discharge light is emitted into the grounded tank l from a cut in the shield of the vacuum vessel (between the end plate of the vacuum vessel and the end of the shield).

This discharge light is detected by a cylindrical fluorescent resin member 18.18, converted into fluorescent light, transmitted to a linear fluorescent resin member 19.19, and then input into an optical fiber 20.20.

Here, the operation of detecting a decrease in the degree of vacuum when the vacuum interrupter 2 shown in FIG. 1 is configured as shown in FIG. 3 will be described.

When the degree of vacuum of the vacuum interrupter 2 inserted in the system electrical circuit is normal, the first. Second vacuum gap Q, (1
, so no signal is sent to the detectors 2177z and the like. When the degree of vacuum decreases here, the first vacuum gap Q between the intermediate shield 25 and the fixed electrode rod 26
, begins to discharge. The reason for this is that in the region around 10-''xxHg of the Paschen curve shown in FIG. Since this is the maximum distance between members with different potentials, local discharge first begins at this first vacuum gap I21.The insulation n27 (this cylinder is made of glass) due to the discharge at this time The discharge light is received by the cylindrical fluorescent resin member 18.The fluorescent resin member 18 converts the received light into fluorescent light, and then transmits it to the optical fiber 20 via the linear fluorescent resin member 19 for detection. When the received light beam is applied to the terminal A of the detector 21, the detector 21 supplies a signal to the cutoff command section 22.The cutoff command section 22 is supplied with the signal from the detector 2. When the input light beam reaches terminal B of the detector 21, the input light beam does not arrive at the terminal B of the detector 21, but when the light beam arrives at the terminal B, the second vacuum is activated. This occurs only when the gear pump discharges.The second vacuum gear h discharges when the degree of vacuum decreases to the point where it cannot be shut off as described above, so the detector 21
When the light beam arrives at both terminals A and B, an auxiliary switch or the like is used, for example, to notify that fact.

The operational status of the above-mentioned detector 21 is summarized in a table as follows.

In the above embodiment, a gap is provided between the fixed electrode rod 26 and the intermediate shield 25, which is the maximum distance.
In Fig. 3, in order to avoid flashover on the fixed side and movable side, if it is on either the fixed side or the movable side, not only the electrode rod but also the grid potential members such as the metal end plates 28a and 28b, and the intermediate shield. between the member 25 when the degree of vacuum is reduced,
It is also possible to provide a first vacuum gap that discharges in a vacuum region that can be shut off. In addition, in this embodiment, detection can be performed not only in the closed state but also in the open state, and in this case, it is necessary to provide the first vacuum gap on the side that is the live part side of either the fixed side or the load. There is. Furthermore, although the above embodiment has described the case of detecting the discharge light in the first and second vacuum gaps, it is sufficient to detect the discharge light in the first vacuum gap, which is a long gap. This is because the leak is often relatively slow at the beginning of the leak when the degree of vacuum decreases. In addition, the third
In the figure, 29 is a movable rod and 30 is a bellows.

! -■9 Effects of the Invention As described above, according to the present invention, there is a connection between the intermediate shield and the grid potential member on either the fixed side or the movable side when the degree of vacuum is reduced and it is possible to disconnect Since the first vacuum gap that discharges in the region is formed, discharge occurs on either the fixed side or the movable side at the beginning of leakage (high vacuum) when the degree of vacuum decreases.

Since the light rays from this discharge were detected by a cylindrical fluorescent resin member installed inside the grounded tank, the saw had a wide light collection area and could increase the amount of light collected. In addition, there is no directivity unlike the conventional method using lenses, and the structure is simple. Furthermore, since the discharge light is detected by the fluorescent resin member, the light is converted into a fluorescent light, so even if it is input to the optical fiber, it is not attenuated by the optical fiber, and the degree of vacuum can be reliably lowered.

[Brief explanation of the drawing]

FIG. 1 is a sectional view showing an embodiment of the present invention, FIG. 2A,
B is an explanatory diagram showing details of important parts, FIG. 3 is a sectional view of the vacuum interrupter, and FIG. 4 is a curve diagram showing the relationship between the degree of vacuum and the discharge starting voltage when the back window gap length is different. ! ...Grounded tank, 2...Vacuum interrupter, 18
゜18...Cylindrical fluorescent resin member, 19.19...
Linear fluorescent resin member, 20.20... optical fiber, 2
I: Detector, 22: Shutoff command section. Detailed explanatory diagram of main parts of 2 people Figure 2

Claims (1)

[Claims] (1) Both ends of the glass insulating cylinder are closed with end plates to form a vacuum vessel, and a fixed electrode rod is airtightly introduced into the vacuum vessel from one end plate, and the fixed electrode rod is approached and separated from the other end plate. A freely movable electrode rod is introduced airtightly through a bellows, and a pair of fixed and movable electrodes that can be freely approached and separated is provided at each inner end of these electrode rods, and at least the outer periphery of the electrode is provided in the vacuum container. A device for detecting a decrease in the degree of vacuum in a vacuum interrupter capable of freely opening and closing a system electrical circuit, which is provided with a metal intermediate shield surrounding an electrode insulated from the electrode, comprising a gas insulated device housing the vacuum container, and the gas insulated device. A cylindrical fluorescent resin member disposed on the inner wall of the vacuum vessel in a coaxial direction with the vacuum vessel so that the discharge light beam within the vacuum vessel can be detected, and a part of this cylindrical fluorescent resin member is cut. Then, a linear fluorescent resin member was inserted into the cut portion, and this linear fluorescent resin member was led out to the outside of the equipment along the inner wall of the gas-insulated equipment, and one end was optically coupled to the leading end. 1. A vacuum degree drop detection device for a vacuum interrupter, comprising an optical fiber and a detector connected to the other end of the optical fiber and configured to send a cutoff command when detecting a discharge beam from a vacuum container.