Gas circuit breaker

Abstract

To reduce the occurrence of a short circuit due to the lowering of the insulation strength of a bushing caused by the accumulation of snow on the upper part of a gas tank by suppressing the occurrence of snow accumulation on the gas tank constituting a gas circuit breaker.SOLUTION: The gas circuit breaker includes a gas tank that accommodates a main circuit conductor and a switching contact portion, a bushing that is connected to an external air circuit, and a rib that is formed on an upper portion of the gas tank. To reduce the occurrence of short-circuiting or the like by a method wherein a rib formed on the upper part of a gas tank has such a structure as to prevent the accumulation of snow on the upper part of the gas tank and the accumulation of snow does not approach a bushing.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] An embodiment of the present invention relates to a gas circuit breaker that is installed outdoors. [Background technology]

[0002] Gas circuit breakers, which are connected to air-insulated overhead lines using bushings, have been known for some time as devices for breaking and making large currents. The length of this bushing is usually standardized under certain conditions according to the required insulation distance in the atmosphere, taking into account dry, wet, or broken conditions. Therefore, when manufacturing a gas circuit breaker, the length of the bushing is appropriately selected from these standardized lengths.

[0003] However, in actuality, in the case of a gas circuit breaker to be installed outdoors, if the length of the bushing is selected simply by considering the required insulation distance in the atmosphere as described above and the gas circuit breaker is manufactured, there are cases where it is not possible to maintain sufficient insulation strength. For example, in areas with heavy snowfall in winter, if snow accumulates on the gas circuit breaker and the snow surface comes close to the air-borne high voltage part above the bushing, the insulation strength of the bushing may be significantly reduced, which may hinder safe operation. Countermeasures to prevent the deterioration of insulation strength due to snowfall include making the tip of the bushing or the top of the control box into a shade or roof shape to allow snow to fall off the gas circuit breaker, and installing a snow melting heater to melt the snow. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Publication No. 8-321231 Summary of the Invention [Problem to be solved by the invention]

[0005] However, umbrella-shaped or roof-shaped structures may be insufficient in cases of heavy snowfall or depending on the snow quality, as accumulated snow may not fall off sufficiently. Also, structures that incorporate snow melting heaters require a separate heater power supply.

[0006] The gas circuit breaker also has a cylindrical gas tank that houses the main circuit conductors. This gas tank is located below the bushing, and due to its shape, no structure is provided to protect it from snow accumulation. However, if snow accumulates on top of the gas tank and the snow surface comes close to the high-voltage part on top of the bushing, the insulation strength of the bushing may decrease, which could cause a short circuit or other problem.

[0007] The present invention has been made in view of the above, and has an object to reduce the accumulation of snow on a gas tank that constitutes a gas circuit breaker. [Means for solving the problem]

[0008] The gas circuit breaker of the embodiment comprises a gas tank that houses a main circuit conductor and a switching contact portion, a bushing that connects to an external air circuit, and a rib formed on the upper part of the gas tank. [Brief explanation of the drawings]

[0009] [Figure 1] FIG. 1 is a configuration diagram of a gas circuit breaker according to a first embodiment. [Figure 2] FIG. 2 is a configuration diagram of a gas circuit breaker according to the second embodiment. [Figure 3] FIG. 3 is a configuration diagram of a gas circuit breaker according to the third embodiment. [Figure 4] FIG. 4 is a configuration diagram of a gas circuit breaker according to the fourth embodiment. [Figure 5] FIG. 5 is a configuration diagram of a gas circuit breaker according to the fifth embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0010] Hereinafter, embodiments will be described with reference to the drawings. FIG. 1 is a configuration diagram of a gas circuit breaker according to a first embodiment. The gas circuit breaker comprises a gas tank 1 that houses the switching contacts together with an insulating medium, a bushing 2 provided on the top of the gas tank to connect the switching contacts to an external air circuit, and a bushing current transformer container 3 that houses a current transformer that measures the current flowing through it.

[0011] The gas tank 1 is a cylindrical metal tank, and is provided with a main circuit conductor and a switch contact unit having a pair of contacts that can be connected and disconnected in the axial direction inside the tank. The switch contact unit is, for example, a vacuum valve.

[0012] The bushing 2 is attached at an angle to the top of the gas tank. The bushing 2 has a hollow insulator and a conductor that passes through the hollow insulator, and an external electrode is attached to the tip of the hollow insulator to be connected to an external air circuit.

[0013] The bushing current transformer container 3 is provided between the gas tank 1 and the bushing 2, and houses a detector for measuring the current flow.

[0014] Here, the structure of the gas tank 1 will be described with reference to the AA cross section of FIG. The gas tank 1 has a rib 11 extending upward at the top of the cylindrical housing. The upper end of the rib 11 is rounded to prevent snow from accumulating. The shape of the upper end may be pointed as long as it prevents snow from accumulating.

[0015] According to this embodiment, the rib on the top of the gas tank prevents snow from accumulating on the top of the gas tank, preventing snow from coming close to the high-voltage part on the top of the bushing and reducing the occurrence of short circuits.

[0016] Next, a second embodiment will be described. Fig. 2 is a configuration diagram of a gas circuit breaker according to the second embodiment. Note that the same components as those in the first embodiment are given the same reference numerals and their description will be omitted. In the second embodiment, rod-shaped structures 21 are provided in place of the ribs 11 of the first embodiment.

[0017] The rod-shaped structure 21 is provided on the upper part of the gas tank and between the pair of bushings. In Fig. 2, a mounting part (not shown) is provided on the bushing current transformer container, and the rod-shaped structure 21 is attached to the mounting part. As a result, a rod-shaped structure 21 is disposed on top of the gas tank 1, as shown in the AA cross section of FIG.

[0018] According to this embodiment, a rod-shaped structure is provided on the top of the gas tank, which prevents snow from accumulating on the top of the gas tank. This prevents snow from coming close to the high-voltage part on the top of the bushing, reducing the occurrence of short circuits and other problems. Also, by using a rod-shaped structure, it is possible to reduce the amount of steel used compared to the rib structure of the first embodiment. Furthermore, by using a structure that is attached to the mounting part, it is possible to remove it outside of the snowfall season, and it is possible to reduce contact with flying objects due to the influence of the wind.

[0019] Next, a third embodiment will be described. Fig. 3 is a configuration diagram of a gas circuit breaker according to the third embodiment. Note that the same components as those in the first embodiment are given the same reference numerals and their description will be omitted. In the third embodiment, a roof-like structure 31 is provided in place of the rib 11 of the first embodiment.

[0020] The roof-like structure 31 is provided on the top of the gas tank and between the pair of bushings. In Fig. 3, a mounting portion (not shown) is provided on the bushing current transformer container, and the rod-like structure 21 is attached to the mounting portion. As a result, a roof-like structure 31 is disposed on top of the gas tank 1, as shown in the AA cross section of FIG.

[0021] According to this embodiment, a roof-like structure is provided on top of the gas tank, which prevents snow from accumulating on the top of the gas tank. This prevents snow from coming close to the high-voltage part on the top of the bushing, reducing the occurrence of short circuits and other problems. In addition, by using a roof-like structure, it is possible to reduce the amount of steel used compared to the rib structure of the first embodiment. Furthermore, by using a structure that is attached to the mounting part, it can be removed outside of the snowfall season, and contact with flying objects due to the influence of wind can be reduced.

[0022] Next, a fourth embodiment will be described. Fig. 4 is a configuration diagram of a gas circuit breaker according to the fourth embodiment. Note that the same components as those in the second embodiment are given the same reference numerals and their description will be omitted. In the fourth embodiment, the rod-shaped structure 21 of the second embodiment is replaced with a rod-shaped structure 41 made of a magnetic material, so that the rod-shaped structure 41 functions as a heater that melts snow.

[0023] The rod-shaped structure 41 is provided on the upper part of the gas tank and between the pair of bushings. In Fig. 4, a mounting part (not shown) is provided on the bushing current transformer container, and the rod-shaped structure 41 is attached to the mounting part. As a result, as shown in the AA cross section of Fig. 4, a rod-shaped structure 41 is disposed on top of the gas tank 1. A main circuit conductor 42 is housed inside the gas tank 1, and the rod-shaped structure 41 and the main circuit conductor 42 are disposed side by side.

[0024] Here, the mechanism by which the rod-shaped structure 41 functions as a heater will be described. As shown in the AA cross section of FIG. 4, a main circuit conductor 42 is housed inside the gas tank 1, and a current of several thousand amperes flows through the main circuit conductor for transmitting electricity. The current flowing through the main circuit conductor 42 generates a magnetic field around the main circuit conductor 42 according to Ampere's law. In the rod-shaped structure 41, an electromotive force and an eddy current are generated due to electromagnetic induction caused by the generation and change of the magnetic field. This eddy current generates Joule heat in the rod-shaped structure 41, and the heat from the rod-shaped structure 41 can melt the snow that has accumulated on the rod-shaped structure 41 and around the rod-shaped structure 41.

[0025] According to this embodiment, a rod-shaped structure is provided on the top of the gas tank, which prevents snow from accumulating on the top of the gas tank. This prevents snow from coming close to the high-voltage part on the top of the bushing, reducing the occurrence of short circuits and other problems. Also, by using a rod-shaped structure, it is possible to reduce the amount of steel used compared to the rib structure of the first embodiment. Furthermore, by using a structure that is attached to the mounting part, it is possible to remove it outside of the snowfall season, and it is possible to reduce contact with flying objects due to the influence of the wind.

[0026] Furthermore, by making the rod-shaped structure magnetic, it can function as a heater by generating heat under the influence of the magnetic field from the current flowing through the main circuit conductor, making it possible to melt snow on the rod-shaped structure and around the rod-shaped structure without having to prepare a power source for the heater.

[0027] Next, a fifth embodiment will be described. Fig. 5 is a configuration diagram of a gas circuit breaker according to the fifth embodiment. Note that the same components as those in the third embodiment are given the same reference numerals and their description will be omitted. In the fifth embodiment, the roof-like structure 31 of the third embodiment is replaced with a roof-like structure 51 made of a magnetic material, allowing the roof-like structure 51 to function as a heater that melts snow.

[0028] The roof-like structure 51 is provided above the gas tank and between the pair of bushings. In Fig. 5, a mounting portion (not shown) is provided on the bushing-current transformer container, and the roof-like structure 51 is attached to the mounting portion. As a result, as shown in the AA cross section of Fig. 5, a roof-like structure 51 is disposed on top of the gas tank 1. A main circuit conductor 52 is housed inside the gas tank 1, and the rod-like structure 51 and the main circuit conductor 52 are disposed side by side.

[0029] Here, the mechanism by which the rod-shaped structure 51 functions as a heater will be described. As shown in the AA cross section of FIG. 5, a main circuit conductor 52 is housed inside the gas tank 1, and a current of several thousand amperes flows through the main circuit conductor for power transmission. The current flowing through the main circuit conductor 52 generates a magnetic field around the main circuit conductor 52 according to Ampere's law. In the roof-like structure 51, an electromotive force and an eddy current are generated due to electromagnetic induction caused by the generation and change of this magnetic field. This eddy current generates Joule heat in the roof-like structure 51, and the heat from the roof-like structure 51 can melt the snow that has accumulated on the roof-like structure 51 and around the roof-like structure 51.

[0030] According to this embodiment, a roof-like structure is provided on top of the gas tank, which prevents snow from accumulating on the top of the gas tank. This prevents snow from coming close to the high-voltage part on the top of the bushing, reducing the occurrence of short circuits and other problems. In addition, by using a roof-like structure, it is possible to reduce the amount of steel used compared to the rib structure of the first embodiment. Furthermore, by using a structure that is attached to the mounting part, it can be removed outside of the snowfall season, and contact with flying objects due to the influence of wind can be reduced. Furthermore, by making the roof-like structure a magnetic material, it can function as a heater by generating heat due to the influence of the magnetic field from the current flowing through the main circuit conductor, and snow accumulated on the roof-like structure and around the roof-like structure can be melted without having to prepare a power source for the heater.

[0031] Although several embodiments of the present invention have been described above, these embodiments are presented as examples and are not intended to limit the scope of the invention. These novel embodiments can be embodied in various other forms, and various omissions, substitutions, and modifications can be made without departing from the spirit of the invention. These embodiments and their modifications are included within the scope and spirit of the invention, and are also included in the scope of the invention and its equivalents as defined in the claims. [Explanation of symbols]

[0032] 1. Gas tank 2. Bushing 3. Bushing current transformer container 11. Ribs 21, 41... Rod-shaped structure 31, 51... Roof-like structure

Claims

1. a gas tank that accommodates a main circuit conductor and a switching contact; a bushing for connecting to an external air circuit; a rib formed on an upper portion of the gas tank; A gas circuit breaker comprising:

2. a gas tank that accommodates a main circuit conductor and a switching contact; a bushing for connecting to an external air circuit; a rod-shaped structure provided on an upper portion of the gas tank; A gas circuit breaker comprising:

3. a gas tank that accommodates a main circuit conductor and a switching contact; a bushing for connecting to an external air circuit; a roof-like structure formed on an upper portion of the gas tank; A gas circuit breaker comprising:

4. 3. The gas circuit breaker according to claim 2, wherein the rod-shaped structure is made of a magnetic material.

5. 4. The gas circuit breaker according to claim 3, wherein the roof-like structure is made of a magnetic material.

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