JPS648415B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for checking the degree of vacuum in a vacuum shearing device.

In general, the shearing ability of a vacuum shear breaker is greatly affected by the quality of the internal vacuum, so it is necessary to check the vacuum. However, in mini-clad or super-clad type compact substation equipment or tank-type vacuum breaker equipment, the vacuum breaker is housed in a metal case together with an insulating medium, and is attached to the bus bar with bolts. ,
When checking the degree of vacuum, the bolts were removed, the vacuum shield was pulled out of the metal case, and the withstand voltage between the electrodes was checked. For this reason, it takes a very long time to check the degree of vacuum, and there are disadvantages such as accidents caused by forgetting to tighten bolts, and the necessity to replenish insulating medium leaked during the check.

The present invention is an attempt to eliminate the above-mentioned drawbacks, and is to provide a vacuum shear breaker which is housed in a metal case together with an insulating medium. It is an object of the present invention to provide a method for checking the degree of vacuum of a vacuum shearing device, which can check the degree of vacuum in the state of .

Embodiments of the present invention will be described below with reference to the drawings.
First, to explain the basic idea of the present invention, in a vacuum shield disconnector, there is an electrode of the vacuum shield disconnector and a metal member surrounding this electrode, such as a shield or a metal cylinder connecting two insulating cylinders. When the degree of vacuum deteriorates, the equivalent resistance between the metal member and the electrode decreases rapidly, the shared voltage between them decreases, and the potential of the metal member increases. Therefore, the electric field near the vacuum chamber and the outer periphery of the disconnector also increases rapidly. Therefore, as shown in FIG. 1, there is a light emitting section 1, a polarizer 2 that linearly polarizes the light from the light emitting section 1, and an electric current that rotates the plane of polarization of the light from the polarizer 2 according to the magnitude of the electric field. an optical effect element (Pockels element or Kerr element) 3; an analyzer 4 which receives light from the element 3 and has a polarization plane that is parallel or perpendicular to the polarization plane of the polarizer 2; and light from the analyzer 4. receive,
If a light receiving section 5 is provided that outputs an electric signal according to the amount of light, and the element 3 is installed on the outer periphery of the vacuum shield or disconnector, if the degree of vacuum deteriorates, the electric field around the vacuum shield or disconnector will increase. The angle of rotation of the plane of polarization in element 3 increases. Therefore, when the polarization planes of the polarizer 2 and the analyzer 4 are in a parallel relationship, the amount of light passing through the analyzer 4 becomes small and the output of the light receiving section 5 becomes small. In some cases, the amount of light passing through the analyzer 4 increases and the output of the light receiving section 5 increases. Therefore, deterioration in the degree of vacuum can be detected from changes in the amount of light passing through the analyzer 4 or the output of the light receiving section 5.

2A to 2C show a superclad type vacuum breaker according to the first embodiment of the present invention, in which a vacuum breaker 7 for three phases is housed in a metal case 6. The disconnector 7 is attached to the bus bar or the like with bolts.
Further, an insulating medium 8 such as an insulating gas or an insulating oil is sealed inside the metal case 6. Vacuum cutter 7
End plates 10 and 11 are attached to both ends of an insulating cylinder 9 to form a vacuum vessel, and a fixed lead 12 having a fixed electrode 12a at the tip is inserted into the vacuum vessel, and a movable lead having a movable electrode 13a at the tip is inserted into the vacuum vessel. The lead 13 is inserted through the bellows 14, and the shield 15 is attached to the middle of the insulating cylinder 9. The vacuum shield of the metal case 6 and the outer periphery of the disconnector 7, especially the shield 15
A hole 6a is provided at a position corresponding to the outer periphery of the metal case 6, and an insulator case 16, which is recessed inward of the metal case 6, is tightly tightened with a bolt 18 via a packing 17. A pressure contact rubber 19 is housed inside the insulation case 16 to prevent partial discharge from occurring inside the case 16, and a pressure contact rubber 19 is placed on the outer surface of the insulator case 16.
The lid 20 is fastened to the flange portion 6b of the metal case 6 with bolts 21 so as to press the lid 20. The lid 20 is formed by applying conductive paint or metallicon to the outer surface of an organic material such as metal or plastic, or by applying conductive paint or metallicon to the surface of an inorganic material such as ceramic, and by attaching it to the metal case 6 at earth potential. Set to earth potential to prevent electric shock. Incidentally, insulating oil or insulating gas may be filled inside the insulating material case 16 instead of the press-contacting rubber 19. In this case, the lid 20 is installed in a sealed manner using a gasket or the like.

On the other hand, FIGS. 3A to 3C show a detection rod 22 having an electric field detection function.
2b and the handle part 2 attached to the electric circuit part 22b
2c, and the electric circuit section 22b includes a light emitting section 1.
A meter 23 for determining the degree of vacuum, which accommodates the light receiving section 5 and is electrically connected to the light receiving section 5, is provided. Moreover, a polarizer 2 is attached to the tip of the insulating rod 22a.
An electric field detection unit 24 that includes an electro-optic effect element 3 and an analyzer 4 that are closely housed in an insulating case 24a.
, and connect the light emitting part 1 and the polarizer 2 with the optical fiber 25, and also connect the light receiving part 5 and the analyzer 4.
An optical fiber 26 is used to connect the two.

When checking the degree of vacuum of the vacuum shield and disconnector 7, the lid 20 and the pressure contact rubber 19 are removed and the tip of the detection rod 22 is inserted into the insulator case 16. Light emitting part 1
The light is linearly polarized by the polarizer 2 via the optical fiber 25 and transmitted to the element 3. The electric field at the outer periphery of the shield 15 changes depending on the degree of vacuum inside the vacuum shield breaker 7, and the element 3 is located at the outer periphery of the shield 15 and rotates the plane of polarization in response to the electric field at that position. The rotation angle of the plane of polarization in the element 3 corresponds to the degree of vacuum of the vacuum shield and disconnector 7. The light transmitted through the element 3 is transmitted through the analyzer 4, and the amount of transmitted light increases or decreases depending on the magnitude of the rotation angle of the polarization plane in the element 3. The light is further transmitted to the light receiving section 5 through the optical fiber 26 and converted into an electrical signal having a magnitude corresponding to the amount of light. This electrical signal is applied to meter 23, which operates in response to the electrical signal. Therefore, from the display on the meter 23, it is possible to judge whether the degree of vacuum in the vacuum chamber breaker 7 is good or bad. Once the degree of vacuum has been checked in this manner, the pressure contact rubber 19 and the lid 20 may be reattached. In the above detection rod 22, an electric field detection section 24 is provided at the tip of the insulating rod 22a, and the polarizer 2, element 3, analyzer 4, case 24
Since both a and the optical fibers 25 and 26 are insulative members, they do not disturb the electric field during the vacuum level inspection, causing errors in the vacuum level detection, and there is no risk of electric shock.

4A to 4C show a tank type vacuum breaker according to a second embodiment of the present invention, in which a vacuum breaker 7 is horizontally housed in a tank 27, and an insulating medium 8 is enclosed. A pair of bushings 29 having main circuit terminals 28 at the upper ends are attached to the upper part of the tank 27. The vacuum shield disconnector 7 is attached to a support fitting or the like with bolts and is electrically connected to the main circuit terminal 28. Also, in this case, a hole 27a is provided at a position corresponding to the outer periphery of the vacuum shield and disconnector 7 of the tank 27, particularly the outer periphery of the shield 15, and an insulating case recessed toward the inside of the tank 27 is provided in the hole 27a. 28
are closely attached to the bolts 30 through the packing 29, and a pressure welding rubber 31 is housed in the insulator case 28 to prevent partial discharge, and the insulator case 28
A lid 32 is attached to the flange portion 27b of the tank 27 with bolts 33 so as to press the pressure-contact rubber 31 on the outer surface of the tank 27. In this case as well, the lid 32 may be formed of a metal or an insulating material with a conductive member attached to the outer surface to provide a ground potential, and an insulating gas or an insulating medium may be filled instead of the press-contact rubber 31. In the second embodiment as well, the degree of vacuum is checked using the detection rod 22.
This is done in the same manner as in the example.

As described above, in the present invention, in a vacuum breaker device in which a vacuum breaker and an insulating medium are housed in a metal case, holes are provided at positions corresponding to the outer periphery of the vacuum breaker and breaker in the metal case. An insulator case recessed toward the inside of the metal case is tightly attached to the hole, and a cover with earth potential is detachably attached to the outside of the insulator case, and the cover is removed when inspecting the vacuum level of the vacuum shield or disconnector. The degree of vacuum is checked by inserting a detection rod with an electric field detection function into the insulator case.If the degree of vacuum in the vacuum shield or disconnector deteriorates, the electric field around the outer circumference of the vacuum shield or disconnector changes. Deterioration of the degree of vacuum can be detected by detecting this electric field change with a detection rod. Therefore, when inspecting the vacuum level, there is no need to remove the vacuum shield or disconnector and pull it out to the outside as in the conventional case, and the vacuum level can be inspected with the vacuum shield or disconnector attached. For this reason,
In addition to significantly reducing inspection time, it also prevents accidents caused by forgetting to tighten bolts when reinstalling vacuum shields and disconnectors, and electric shock accidents when installing and removing vacuum shields and disconnectors. Since it is separate from the vacuum shearing device, maintenance and inspection thereof is easy, and it can be used in common with a plurality of vacuum shearing devices.

[Brief explanation of drawings]

FIG. 1 is an explanatory diagram for explaining the basic idea of the present invention, and FIGS. 2A to 2C are a plan view and a side view, respectively, of a superclad type vacuum shear cutting apparatus according to the first embodiment of the present invention. 3A to 3C are respectively a front view of the detection rod according to the present invention, a sectional view and a functional configuration diagram of the electric field detection part thereof, and FIGS. 4A to C are respectively the present invention A front view, a side view, and its A of the tank-type vacuum shearing device according to the second embodiment of
Part enlarged sectional view. DESCRIPTION OF SYMBOLS 1... Light emitting part, 2... Polarizer, 3... Electro-optic effect element, 4... Analyzer, 5... Light receiving part, 6...
Metal case, 6a...hole, 7...vacuum shield, disconnector,
8... Insulating medium, 16, 28... Insulating material case,
17, 29...Packskin, 19,31...Pressure rubber, 20,32...Lid, 22...Detection rod, 24...
...Electric field detection section, 27...tank, 27a...hole.

Claims (1)

[Claims] 1. In a vacuum shield disconnector having a metal member surrounding an electrode in a metal case and a vacuum shield disconnector device housing an insulating medium, a hole is formed at a position corresponding to the metal member on the outer periphery of the vacuum shield disconnector in the metal case. At the same time, an insulator case recessed inward of the metal case is closely attached around the hole, and a cover with earth potential is detachably attached to the outer surface of the insulator case, and the cover must be removed during inspection. A method for inspecting the degree of vacuum of a vacuum breaker, which comprises inserting a detection rod with an electric field detection function into an insulator case to check the degree of vacuum of the breaker.