Gas-insulated switchgear

Abstract

To provide a gas-insulation switchgear capable of appropriately discharging insulation gas.SOLUTION: A gas-insulation switchgear includes a container and a pressure discharging device. The container encapsulates a conductor and insulation gas inside. The pressure discharging device is provided at an opening of the container and can discharge the insulation gas from a discharge port to the outside of the container in response to pressure of the insulation gas. A vertical range that can be reached by a hand of a maintenance worker in a horizontal region into which the maintenance worker enters during electrification is taken as a work space. The discharge port is arranged so as not to face the work space.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] Embodiments of the present invention relate to a gas-insulated switchgear.

Background Art

[0002] Gas-insulated switchgears are used in power plants or substations. A gas-insulated switchgear has a container that encloses a conductor and an insulating gas therein. In the event of an internal accident accompanied by the occurrence of an arc (hereinafter referred to as an internal arc), the pressure of the insulating gas rapidly increases. A pressure relief device is attached to release the insulating gas to the outside of the container in response to the pressure of the insulating gas. There is a need for a gas-insulated switchgear that can appropriately release the insulating gas.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] The problem to be solved by the present invention is to provide a gas-insulated switchgear that can appropriately release the insulating gas.

Means for Solving the Problems

[0005] The gas-insulated switchgear of the embodiment includes a container and a pressure relief device. The container encloses a conductor and an insulating gas therein. The pressure relief device is installed at an opening of the container and can release the insulating gas from a discharge port to the outside of the container in response to the pressure of the insulating gas. A working space is defined as a horizontal area where a maintenance worker can enter during energization and a vertical range within reach of the maintenance worker's hand. The discharge port is arranged so as not to face the working space. The discharge port is arranged within the range of the working space in the vertical direction. It has a shielding plate arranged between the discharge port and the working space.

Brief Description of the Drawings

[0006]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Figure 8

Mode for Carrying Out the Invention

[0007] Hereinafter, the gas-insulated switchgear of the embodiment will be described with reference to the drawings. (First Embodiment) FIG. 1 is a front view of the gas-insulated switchgear of the first embodiment. FIG. 2 is a planar cross-sectional view taken along line II-II of FIG. 1. In the present application, the Z direction, X direction, and Y direction of the orthogonal coordinate system are defined as follows. The Z direction is the vertical direction, and the +Z direction is the upward direction. The X direction and Y direction are the horizontal directions. The X direction is the direction in which the circuit breaker 6 extends, and the Y direction is the direction in which the main bus 2 (see FIG. 1) extends.

[0008] As shown in FIG. 1, the gas-insulated switchgear (GIS) 1 has a circuit disposed between the main bus 2 and a power transmission line (not shown). The cable head 9 of the gas-insulated switchgear 1 is connected to the power transmission line.

[0009] Figure 3 is a cross-sectional view taken along line III-III of Figure 1. The electric circuit of the gas-insulated switchgear 1 is formed by a conductor 15 and a container 16 that covers the outer periphery of the conductor 15. The container (tank) 16 is formed by welding a metal pipe or metal plate, or by casting, etc. An insulating gas G such as SF6 is enclosed inside the container 16. As shown in Figure 1, the electric circuit of the gas-insulated switchgear 1 is separated into a plurality of gas compartments by insulating spacers S. The insulating spacer S supports the conductor 15 and partitions the inside of the container 16 in the extending direction of the conductor 15.

[0010] The gas-insulated switchgear 1 has a circuit breaker 6, a main bus side circuit breaker / earthing switch 3, and a transmission line side circuit breaker / earthing switch 8. The circuit breaker 6 opens the circuit between the main bus 2 and the transmission line to cut off the current.

[0011] The main bus side circuit breaker / earthing switch (hereinafter simply referred to as the main bus side circuit breaker) 3 opens the circuit between the main bus 2 and the circuit breaker 6. The main bus side circuit breaker 3 grounds the circuit breaker 6 side after opening. A pair of main bus side circuit breakers 3 are connected to a pair of main buses 2. The pair of main bus side circuit breakers 3 are connected to the circuit breaker 6 via a connecting bus 4. The transmission line side circuit breaker / earthing switch (hereinafter simply referred to as the transmission line side circuit breaker) 8 opens the circuit between the circuit breaker 6 and the transmission line. The transmission line side circuit breaker 8 grounds the circuit breaker 6 side after opening.

[0012] The gas-insulated switchgear 1 has a pressure relief device 20. The pressure relief device 20 is installed in each of the plurality of gas compartments separated by the insulating spacer S. In the example of Figure 1, all the pressure relief devices 20 are arranged in the -Y direction of the container 16. Hereinafter, taking the pressure relief device 36 installed in the gas compartment of the circuit breaker 6 as a representative example, it will be described with reference to Figure 3. The pressure relief devices 20 in other gas compartments are the same as the pressure relief device 36 in the gas compartment of the circuit breaker 6.

[0013] Figure 3 is an explanatory diagram of the pressure relief device. When an internal arc occurs in the container 16, the temperature and pressure of the insulating gas G increase. The pressure relief device 36 can discharge the insulating gas G to the outside of the container 16 corresponding to the pressure of the insulating gas G.

[0014] The pressure relief device 36 is installed at the opening 21 that communicates the inside and outside of the container 16. The pressure relief device 36 has a rupture disk 23 and a cover 24. The rupture disk (rupture disk) 23 closes the opening 21. The rupture disk 23 ruptures when the pressure of the insulating gas G becomes equal to or higher than the operating pressure of the pressure relief device 36, and opens the opening 21. The operating pressure of the pressure relief device 36 is lower than the withstand voltage (allowable pressure) of the container 16 and the insulating spacer S. The cover 24 is attached to the outer surface of the container 16 and covers the outside of the rupture disk 23. The cover 24 has a gas discharge port 25 for the insulating gas G.

[0015] In the normal operating state of the gas-insulated switchgear 1, no internal arc occurs in the container 16. In this state, the pressure of the insulating gas G is less than the operating pressure of the pressure relief device 36. When an internal arc occurs and the pressure of the insulating gas G becomes equal to or higher than the operating pressure of the pressure relief device 36, the rupture disk 23 ruptures and the opening 21 is opened. The high-pressure insulating gas G passes through the opening 21 of the container 16, collides with the cover 24, and is discharged to the outside through the discharge port 25.

[0016] As shown in FIG. 2, the gas-insulated switchgear 1 has a circuit 10 composed of a plurality of phases. In the example of FIG. 2, the plurality of phases are three phases 11-13. Each of the three phases 11-13 has the circuit shown in FIG. 1. The three phases 11-13 each extend in the X direction and are arranged side by side in the Y direction. The gas-insulated switchgear 1 has a plurality of circuits 10A, 10B. The plurality of circuits 10A, 10B are arranged side by side in the Y direction.

[0017] As shown in FIG. 1, there may be cases where a maintenance worker P performs maintenance work such as inspection of the gas-insulated switchgear 1. The work space 18 of the maintenance worker P is defined as follows. The working space 18 in the Z direction (vertical direction) is the range that can be reached by the hands of the maintenance worker P. The height of the working space 18 is the height L1 from the ground to the fingertips of the maintenance worker P when the maintenance worker P stands on the ground and stretches the arm upward. The size such as the height and arm length of the maintenance worker P is defined by the average size of the general public.

[0018] In order to perform maintenance work at high places of the gas-insulated switchgear 1, a workbench 19 may be installed. The range that can be reached by the hands of the maintenance worker P standing on the workbench 19 is also included in the working space 18. If the height from the ground to the upper surface of the workbench 19 is L2, the height of the working space 18 in the installation area of the workbench 19 is L2 + L1. There may be a case where the maintenance worker P standing on the workbench 19 stretches the hand horizontally to perform maintenance work. Therefore, the height of the working space 18 around the installation area of the workbench 19 is also L2 + L1.

[0019] As shown in FIG. 2, the working space 18 in the XY direction (horizontal direction) is the area where the maintenance worker P enters during energization. The working space 18 is the area around the gas-insulated switchgear 1 in the XY direction. The working space 18 includes the area between a plurality of lines 10A, 10B in the Y direction. The installation area of the workbench 19 (see FIG. 1) is also included in the working space 18.

[0020] The maintenance worker P performs maintenance work on the equipment of the gas-insulated switchgear 1 during power-off and does not perform maintenance work on the equipment during energization. For example, even when the first line 10A among the adjacent lines 10A, 10B is energized, the maintenance worker P performs maintenance work on the second line 10B during power-off. The maintenance worker P does not enter the area between the three phases 11-13 of the energized first line 10A. Therefore, the area between the three phases 11-13 in the Y direction is not the area where the maintenance worker P enters during energization and is not the working space 18.

[0021] The discharge port 25 of the pressure relief device 36 is arranged so as not to face the working space 18. As shown in FIG. 1, the discharge port 25 is arranged at a position higher than the working space 18 in the Z direction. The discharge port 25 faces in the XY plane direction or in the +Z direction from the XY plane direction. In the example of FIG. 1, the discharge port 25 faces in the +Z direction. The discharge port 25 discharges the insulating gas G in the +Z direction.

[0022] As shown in FIG. 2, when an internal arc occurs in the energized first line 10A, the high-temperature and high-pressure insulating gas G is discharged from the discharge port 25 of the pressure relief device 36. There is a possibility that a maintenance worker P who performs maintenance work on the second line 10B during power-off may enter the area around the energized first line 10A.

[0023] The discharge port 25 of the pressure relief device 36 is arranged so as not to face the working space 18. The discharge port 25 does not discharge the high-temperature and high-pressure insulating gas G into the working space 18 where the maintenance worker P performs maintenance work. Therefore, the gas-insulated switchgear 1 can appropriately discharge the insulating gas G.

[0024] (Second Embodiment) FIG. 4 is a front view of the gas-insulated switchgear of the second embodiment. The gas-insulated switchgear 1 of the second embodiment is different from the gas-insulated switchgear 1 of the first embodiment in that the discharge port 25 is connected to the opening 21 of the container 16 via the pipe 26. The description of the second embodiment for the points that are the same as those of the first embodiment may be omitted.

[0025] The gas-insulated switchgear 1 has a connecting bus 7 between the circuit breaker 6 and the transmission line side circuit breaker 8. An insulating spacer SS is arranged between the circuit breaker 6 and the connecting bus 7. A pressure relief device 37 is installed in the gas compartment of the connecting bus 7, and a pressure relief device 36 is installed in the gas compartment of the circuit breaker 6. The entire gas compartment of the circuit breaker 6 is arranged within the range of the working space 18 in the Z direction. Therefore, the opening 21 of the container 16 of the circuit breaker 6 is arranged within the range of the working space 18 in the Z direction.

[0026] The discharge port 25 of the pressure relief device 36 of the circuit breaker 6 is arranged so as not to face the working space 18. The discharge port 25 is arranged at a position higher than the working space 18 in the Z direction. The discharge port 25 faces the XY plane direction or the +Z direction from the XY plane direction. In the example of FIG. 1, the discharge port 25 faces the +Z direction.

[0027] The discharge port 25 is connected to the opening 21 via the pipe 26. The pipe 26 extends in the +Z direction from the opening 21 to the discharge port 25. The rupture disk 23 of the pressure relief device 36 may block the opening 21 or may block the middle part of the pipe 26.

[0028] The insulating gas G that has become high pressure inside the container 16 of the circuit breaker 6 passes through the opening 21 and the pipe 26 and is discharged in the +Z direction from the discharge port 25. Even when the opening 21 is arranged within the range of the working space 18 in the Z direction, the high-temperature and high-pressure insulating gas G is not discharged into the working space 18. Therefore, the gas-insulated switchgear 1 can appropriately discharge the insulating gas G.

[0029] (Third Embodiment) FIG. 5 is a front view of the gas-insulated switchgear according to the third embodiment. FIG. 6 is a plan sectional view taken along line VI-VI of FIG. 5. The gas-insulated switchgear 1 according to the third embodiment is different from the gas-insulated switchgear 1 according to the second embodiment in that the discharge port 25 of the pressure relief device 36 is arranged between adjacent phases 11-13. The description of the third embodiment for the points that are the same as the second embodiment may be omitted.

[0030] As shown in FIG. 5, the entire gas compartment of the circuit breaker 6 is arranged within the range of the working space 18 in the Z direction. The opening 21 of the container 16 of the circuit breaker 6 is arranged within the range of the working space 18 in the Z direction.

[0031] As shown in FIG. 6, the discharge port 25 of the pressure relief device 36 of the circuit breaker 6 is disposed between adjacent phases 11-13. The three phases 11-13 are the first phase 11, the second phase 12, and the third phase 13 from the -Y direction to the +Y direction. In the example of FIG. 6, the discharge port 25 of the pressure relief device 36 of the first phase 11 is installed in the +Y direction of the container 16 and disposed between the first phase 11 and the second phase 12. The discharge port 25 of the pressure relief device 36 of the second phase 12 is installed in the -Y direction of the container 16 and disposed between the first phase 11 and the second phase 12. The discharge port 25 of the pressure relief device 36 of the third phase 13 is installed in the -Y direction of the container 16 and disposed between the second phase 12 and the third phase 13.

[0032] Thus, the discharge port 25 is disposed between adjacent phases 11-13. As described above, the area between the three phases 11-13 is not the area where the maintenance worker P enters during energization and is not the work space 18. The discharge port 25 does not face the work space 18. The high-temperature and high-pressure insulating gas G is not discharged from the discharge port 25 to the work space 18. Therefore, even when the opening 21 is disposed within the range of the work space 18 in the Z direction, the gas-insulated switchgear 1 can appropriately discharge the insulating gas G.

[0033] In the example of FIG. 5, the discharge port 25 faces the +Z direction. The high-temperature and high-pressure insulating gas G is discharged from the discharge port 25 in the +Z direction. There are few constituent devices of the gas-insulated switchgear 1 in the +Z direction of the discharge port 25. The collision of the insulating gas G against the constituent devices of the gas-insulated switchgear 1 is suppressed. Thereby, the deterioration of the constituent devices of the gas-insulated switchgear 1 is suppressed. When the insulating gas G collides with the constituent devices of the gas-insulated switchgear 1 or the ground, the insulating gas G may diffuse into the work space 18. By the discharge port 25 facing the +Z direction, the diffusion of the insulating gas G into the work space 18 is suppressed.

[0034] (Fourth Embodiment) FIG. 7 is a front view of the gas-insulated switchgear according to the fourth embodiment. FIG. 8 is a plan sectional view taken along line VIII-VIII of FIG. 7. The gas-insulated switchgear 1 according to the fourth embodiment is different from the gas-insulated switchgear 1 according to the third embodiment in that it has a shielding plate 28 disposed between the discharge port 25 of the pressure relief device 36 and the working space 18. The description of the fourth embodiment regarding the points that are the same as those of the third embodiment may be omitted.

[0035] As shown in FIG. 7, the entire gas compartment of the circuit breaker 6 is disposed within the range of the working space 18 in the Z direction. The opening 21 of the container 16 of the circuit breaker 6 is disposed within the range of the working space 18 in the Z direction.

[0036] As shown in FIG. 8, the discharge ports 25 of the pressure relief devices 36 of the three phases 11-13 are installed in the -Y direction of the container 16. The discharge ports 25 of the pressure relief devices 36 of the second phase 12 and the third phase 13 are not disposed in the working space 18. In contrast, the discharge port 25 of the pressure relief device 36 of the first phase 11 is disposed in the working space 18. The discharge port 25 of the pressure relief device 36 of the first phase 11 faces the +Z direction.

[0037] A shielding plate 28 is disposed between the discharge port 25 of the pressure relief device 36 of the first phase 11 and the working space 18. The shielding plate 28 covers the -Z direction, -Y direction, and ±X directions of the pressure relief device 36. The +Z direction end of the shielding plate 28 is open. As shown in FIG. 7, the +Z direction end of the shielding plate 28 is disposed at a position higher than the working space 18 in the Z direction.

[0038] Thus, the shielding plate 28 is disposed between the discharge port 25 and the working space 18. The discharge port 25 does not face the working space 18. The insulating gas G discharged from the discharge port 25 passes through the inside of the shielding plate 28 and is discharged from the +Z direction end of the shielding plate 28. The high-temperature and high-pressure insulating gas G is not discharged into the working space 18. Therefore, the gas-insulated switchgear 1 can appropriately discharge the insulating gas G even when the opening 21 is disposed within the range of the working space 18 in the Z direction.

[0039] As described above, the discharge port 25 faces the +Z direction. The collision between the high-temperature and high-pressure insulating gas G and the shielding plate 28 is suppressed. Thereby, the deterioration of the shielding plate 28 is suppressed.

[0040] In the above-described embodiment, the gas compartment of the circuit breaker 6 of the gas-insulated switchgear 1 is arranged within the range of the working space 18 in the Z direction. On the other hand, the gas compartments of other devices of the gas-insulated switchgear 1 may be arranged within the range of the working space 18 in the Z direction. In the above-described embodiment, the three phases 11 - 13 constituting the line 10 each have a separate container 16. On the other hand, the three phases 11 - 13 may be arranged in the same container.

[0041] In the above-described embodiment, the pressure relief device 20 has a rupture disk 23 that closes the opening 21. The rupture disk 23 ruptures when the pressure of the insulating gas G becomes equal to or higher than the operating pressure of the pressure relief device 20, and opens the opening 21. On the other hand, when the pressure of the insulating gas G becomes equal to or higher than the operating pressure of the pressure relief device 20, the pressure relief device 20 may open the opening 21 by means other than the rupture disk 23.

[0042] According to at least one of the embodiments described above, the gas-insulated switchgear 1 has a container 16 and a pressure relief device 20. The container 16 encloses a conductor 15 and an insulating gas G therein. The pressure relief device 20 is installed at the opening 21 of the container 16 and can discharge the insulating gas G from the discharge port 25 to the outside of the container 16 in response to the pressure of the insulating gas G. The working space 18 is defined as the region in the XY direction where the maintenance worker P enters during energization and the range in the Z direction that the hand of the maintenance worker P can reach. The discharge port 25 is arranged so as not to face the working space 18. Thereby, the gas-insulated switchgear 1 can appropriately discharge the insulating gas G.

[0043] Although several embodiments of the present invention have been described, these embodiments are presented by way of example and are not intended to limit the scope of the invention. These embodiments can be implemented in various other forms, and various omissions, replacements, and changes can be made without departing from the gist of the invention. These embodiments and their modifications are included in the scope and gist of the invention, as well as in the invention described in the claims and the equivalent scope thereof.

Explanation of Reference Numerals

[0044] G... Insulating gas, P... Maintenance worker, 1... Gas-insulated switchgear, 10... Circuit, 11, 12, 13... Phases, 15... Conductor, 16... Container, 18... Working space, 20, 36... Pressure relief device, 21... Opening, 25... Discharge port, 26... Pipe, 28... Shielding plate.

Claims

1. a container that encloses a conductor and an insulating gas therein; a pressure relief device installed at an opening of the container and capable of discharging the insulating gas from a discharge port to the outside of the container in response to the pressure of the insulating gas; and when a horizontal area where a maintenance worker enters during energization and a vertical range reachable by the hand of the maintenance worker are defined as a working space, the discharge port is arranged so as not to face the working space; the discharge port is arranged within the range of the working space in the vertical direction; having a shielding plate arranged between the discharge port and the working space; a gas-insulated switchgear.

2. the discharge port is arranged at a position higher than the working space in the vertical direction; the discharge port faces horizontally or vertically upward from the horizontal direction; the gas-insulated switchgear according to Claim 1.

3. the opening is arranged within the range of the working space in the vertical direction; the discharge port is connected to the opening via a pipe; the gas-insulated switchgear according to Claim 1 or 2.

4. comprising the container and having a plurality of phases arranged in parallel to form a circuit; the discharge port is arranged between adjacent ones of the phases; the gas-insulated switchgear according to any one of Claims 1 to 3.

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