Voltage device and cooling water circulation device

Abstract

To provide a voltage device and a cooling water circulation device that can suppress leakage of insulating gas filled in a container to the outside even though a cooler is provided in the container.SOLUTION: A voltage device includes a container 2 filled with insulating gas, a device 3 that is placed in the container 2 and generates heat when supplied with electricity, a cooler 4 that is housed in the container 2 and cools an object to be cooled by heat exchange with cooling water, a circulation flow path 71 that is connected to the cooler 4, which is formed in an annular shape such that cooling water circulates therein, and is provided with a cooling portion 72 that cools the cooling water in a portion outside the container 2, an expansion tank 73 that is provided outside the container 2 in the circulation flow path 71 and opened to the atmosphere, and a gas sensor 74 that is provided in contact with the gas coming out of the expansion tank 73 and detects insulating gas.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a voltage device and a cooling water circulation device, and more particularly to a voltage device having a container filled with an insulating gas and a cooling water circulation device used therein. [Background technology]

[0002] A conventional DC high voltage generator is disclosed in Patent Document 1. The DC high voltage generator described in Patent Document 1 includes a tank filled with a cooling gas and a DC high voltage generating circuit unit disposed in the tank for generating a high voltage.

[0003] This DC high voltage generator is provided with a cooling mechanism for lowering the temperature inside the tank. The cooling mechanism includes a cooler installed outside the tank. The gas inside the tank flows through piping into the cooler outside the tank and is cooled by the cooler. The cooled gas is then introduced back into the tank. In this way, the DC high voltage generator can maintain the inside of the tank at an appropriate temperature. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Publication No. 9-84260 Summary of the Invention [Problem to be solved by the invention]

[0005] As described above, the DC high voltage generator described in Patent Document 1 has a cooler installed outside the tank, but due to issues such as the need to secure installation space, the inventors considered placing the cooler inside the tank and supplying cooling water to the cooler from a cooling device such as a cooling tower or chiller.

[0006] However, if a hole develops in the cooler due to aging or other reasons, the insulating gas in the tank may dissolve into the cooling water. In this case, the cooling water containing the dissolved insulating gas may return to the cooling device, causing the insulating gas to leak outside.

[0007] The present invention has been made in consideration of the above circumstances, and aims to provide a voltage device and a cooling water circulation device that can prevent the insulating gas filled in the container from leaking to the outside while a cooler is installed inside the container. [Means for solving the problem]

[0008] One embodiment of the voltage device of the present invention comprises a container filled with insulating gas, an apparatus placed within the container and generating heat upon receiving a supply of electricity, a cooler housed in the container and cooling an object to be cooled by heat exchange with cooling water, a circulation flow path connected to the cooler, the circulation flow path being formed in a ring shape so that the cooling water circulates and having a cooling section provided outside the container for cooling the cooling water, an expansion tank provided outside the container in the circulation flow path and open to the atmosphere, and a gas sensor provided in contact with gas coming out of the expansion tank for detecting the insulating gas.

[0009] A cooling water circulation device according to one aspect of the present invention is a cooling water circulation device for use in a voltage device including a container filled with an insulating gas, a device disposed within the container that generates heat upon receiving a supply of electricity, and a cooler housed in the container that cools a cooling target by heat exchange with cooling water. The cooling water circulation device includes a circulation flow path connected to the cooler, the circulation flow path being formed in an annular shape so that the cooling water circulates, and having a cooling unit disposed outside the container that cools the cooling water, an expansion tank disposed outside the container in the circulation flow path and open to the atmosphere, and a gas sensor disposed in contact with gas emitted from the expansion tank and that detects the insulating gas. [Effects of the Invention]

[0010] The voltage device and cooling water circulation device of the above aspects of the present invention have the advantage that, even while a cooler is provided inside the container, the insulating gas filled in the container can be prevented from leaking to the outside. [Brief explanation of the drawings]

[0011] [Figure 1] FIG. 1 is a schematic diagram of a voltage device according to one embodiment of the present invention. [Figure 2] FIG. 2 is a schematic diagram of a voltage device according to an embodiment. [Figure 3] FIG. 3 is a cross-sectional view of a container of a voltage device according to an embodiment. [Figure 4] FIG. 4 is a schematic diagram of the expansion tank and its surroundings in the cooling water circulation device according to the embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0012] <Embodiment> The voltage device and the cooling water circulation device 7 according to this embodiment will be described in detail below with reference to the drawings. However, since the drawings are merely schematic illustrations of the embodiment, for example, the positional relationships and sizes of the components may not be accurate.

[0013] A voltage source is a device that operates when a voltage is applied. As shown in FIG. 1, in a voltage source, a device 3 is housed in a container 2 filled with insulating gas (electrical insulating gas). Examples of voltage sources include electron beam irradiation devices, gas circuit breakers, gas insulated switchgears (GIS), instrument transformers (transformers, AC transformers), and high voltage generators. In this embodiment, an electron beam irradiation device 10 will be described as an example of a voltage source.

[0014] 2 shows a schematic diagram of an electron beam irradiation device 10 according to this embodiment. The electron beam irradiation device 10 is a device that generates electron beams and irradiates an object to be irradiated 91 with the electron beams. The electron beam irradiation device 10 according to this embodiment is a scanning type electron beam irradiation device. As shown in FIG. 1, the electron beam irradiation device 10 includes an irradiation device main body 1 and a cooling water circulator 7.

[0015] The irradiation device main body 1 constitutes the main body of the electron beam irradiation device 10. As shown in Fig. 1, the irradiation device main body 1 includes a container 2 filled with insulating gas, a device 3 that generates heat when supplied with electricity, and a cooler 4. The cooler 4 cools the inside of the container 2 with cooling water supplied from a cooling water circulator 7.

[0016] The cooling water circulation device 7 is connected to the cooler 4 and performs cooling by circulating cooling water. As shown in FIG. 1 , the cooling water circulation device 7 includes an annular circulation flow path 71, a cooling unit 72, an expansion tank 73, and a sensor 74 arranged to be in contact with the gas coming out of the expansion tank 73. In the cooling water circulation device 7, because the annular circulation flow path 71 is connected to the cooler 4, even if insulating gas dissolves in the cooling water, leakage to the outside is prevented. Furthermore, because the sensor 74 can detect insulating gas, it is possible to know if a hole has formed in the cooler 4 due to deterioration or damage.

[0017] Here, the "irradiated object 91" of the electron beam irradiation device 10 refers to an object to be irradiated with an electron beam. The irradiated object 91 is not particularly limited, and examples thereof include food, food packaging containers, beverage containers, medical equipment, testing tools, semiconductors, tires, wire coatings, foam sheets, heat-shrinkable tubing, films, hydrogels, silicon carbide fibers, fiber-reinforced plastics, battery separators, adsorbents, functional clothing, outdoor panels, flooring materials, decorative panels, and transfer films. By irradiating the irradiated object 91 with an electron beam, the irradiated object 91 can be subjected to treatments such as crosslinking, modification, hardening, graft polymerization, disinfection, and sterilization.

[0018] The electron beam irradiation device 10 as an example of a voltage device will be described in more detail below.

[0019] (Irradiation device body 1) As described above, the irradiation device main body 1 includes the container 2, the device 3, and the cooler 4, as well as a scan tube 51, a vacuum pump 52, a scan coil 53, and a plurality of power supplies 61 and 62, as shown in Fig. 2. The container 2 accommodates the device 3, the cooler 4, and the plurality of power supplies 61 and 62.

[0020] (Equipment 3) The device 3 generates heat when supplied with electricity from a power source. The device 3 according to this embodiment is an accelerator 31 that accelerates electrons to form an electron flow. The accelerator 31 includes a filament 32, an acceleration tube 33, and a plurality of acceleration electrodes 34.

[0021] The filament 32 generates heat when supplied with electricity from a power source (first power source 61), and as a result of the heat generation, emits electrons. An example of the material of the filament 32 is tungsten. The filament 32 is disposed above the accelerating electrode 34 within the accelerating tube 33.

[0022] The acceleration structure 33 is formed in a cylindrical shape. A filament 32 and an acceleration electrode 34 are disposed inside the acceleration structure 33. The upper end of the acceleration structure 33 is closed and the lower end is open. A scan tube 51 is connected to the lower end of the acceleration structure 33. The acceleration electrodes 34 are arranged at regular intervals along the central axis of the acceleration structure 33. The acceleration electrodes 34 generate a magnetic field when supplied with electricity from a power supply (second power supply 62). The magnetic field generated by the acceleration electrode 34 converges and accelerates the electrons emitted from the filament 32 toward the open end (lower end) of the acceleration structure 33. In this way, the accelerator 31 can generate an electron beam, which is an electron flow along the central axis of the acceleration structure 33.

[0023] The accelerator 31 generates heat when supplied with power from a power source, and at this time, the temperature of the space within the container 2 increases. Therefore, the space within the container 2 is cooled by the cooler 4, which will be described later.

[0024] (Scanning tube 51) The scan tube 51 is connected to the lower end of the accelerating structure 33 and is formed so as to widen downward. An opening window for emitting an electron beam is provided at the lower end of the scan tube 51. A window foil is attached to the opening window. The window foil is made of metal foil. Examples of metal foil include aluminum, titanium, magnesium, and beryllium. The window foil is made of a heat-resistant material with a specific gravity that allows the electron beam to pass through. This forms a sealed space inside the scan tube 51 and the accelerating structure 33. Therefore, the inside of the scan tube 51 and the accelerating structure 33 are maintained in a near-vacuum state by the vacuum pump 52.

[0025] A scan coil 53 is provided on the outer periphery of the upper end of the scan tube 51. The scan coil 53 is supplied with electricity to scan the electron beam generated by the accelerator 31.

[0026] (container 2) The container 2 is hollow and filled with an insulating gas. The pressure inside the container 2 may be equal to or higher than atmospheric pressure, for example, 0.1 MPa or higher, and more preferably 0.5 MPa or higher. There is no particular limit to the upper limit of the pressure inside the container 2, but one example is 2 MPa or lower. The container 2 according to this embodiment is a pressure tank in which both axial end faces of a cylindrical body are closed, but the shape is not limited to a cylindrical shape and, for example, the cross section may be a polygonal shape such as a square or pentagon. The container 2 may also be formed into a spherical shape.

[0027] The insulating gas is a gas having electrical insulating properties. The insulating gas according to this embodiment is an inert gas. Examples of the inert gas include SF6 gas (sulfur hexafluoride gas), a mixed gas of CF3I (trifluoromethane iodide) and N2 (nitrogen), CO2, argon gas, helium gas, and the like, or a mixed gas of these. The insulating gas according to this embodiment is a gas containing SF6 gas (sulfur hexafluoride gas).

[0028] The material of the container 2 is not particularly limited, and may be, for example, iron, aluminum alloy, stainless steel, brass, steel, synthetic resin, glass, or the like.

[0029] (Cooler 4) The cooler 4 cools the object to be cooled by heat exchange with cooling water. The cooler 4 is disposed in the container 2 as shown in FIG. 3. The cooler 4 according to this embodiment cools the insulating gas in the container 2 (i.e., the space inside the container 2) as the object to be cooled. However, in the present invention, the cooler 4 may also cool the heat-generating device 3 by contacting it. Also, a fan may be provided inside the container 2 to create an air current in contact with the cooler 4.

[0030] The cooler 4 is configured by providing cooling fins around a pipe connecting the inlet connection port and the outlet connection port of the cooler 4. By providing the cooling fins, the cooler 4 can effectively exchange heat between the cooling water flowing through the pipe and the insulating gas inside the container 2.

[0031] The cooling water is a cooling medium capable of performing heat exchange in the cooler 4. There are no particular limitations on the cooling water, and examples thereof include pure water, ultrapure water, tap water, chiller water, well water, etc. In this embodiment, tap water is used as the cooling water.

[0032] (Cooling water circulation device 7) 1, the cooling water circulation device 7 is a device that circulates cooling water and supplies the cooling water to the cooler 4. As described above, the cooling water circulation device 7 includes the circulation flow path 71, the cooling unit 72, the expansion tank 73, and the sensor 74. The cooling water circulation device 7 further includes a pair of on-off valves 76, an exhaust valve 78, and a control device 8.

[0033] (Circulation flow path 71, cooling section 72) The circulation flow path 71 constitutes a path through which the cooling water circulates. As shown in Fig. 1, the circulation flow path 71 is connected to the cooler 4 and is formed in a ring shape. Therefore, the cooling water flowing through the circulation flow path 71 leaves the connection port on the outlet side of the cooler 4, makes a circuit, and then re-enters the cooler 4 from the connection port on the inlet side, repeating this process.

[0034] The term "annular" here means that the circulation flow path 71 including the cooler 4 is connected endlessly, and there are no particular limitations on the shape. That is, "annular" includes, for example, an elliptical shape, a triangular shape, a square shape, a pentagonal shape, and other shapes that are not geometrical.

[0035] A portion of the circulation flow path 71 is located inside the container 2, and another portion is located outside the container 2. A cooling unit 72 is provided in a portion outside the circulation flow path 71. The cooling unit 72 cools the cooling water passing through the circulation flow path 71. The cooling unit 72 is included in a heat exchanger 79. The heat exchanger 79 has a primary side heat exchange unit 9 through which the cooling water supplied from the cooling device passes, and a secondary side heat exchange unit that exchanges heat with the primary side heat exchange unit 9. The cooling unit 72 is composed of the secondary side heat exchange unit. The cooling unit 72 can cool the cooling water passing through the circulation flow path 71 by exchanging heat with the primary side heat exchange unit 9.

[0036] The cooling device may be a water-cooled type or an air-cooled type. There are no particular limitations on the cooling device, and examples of the cooling device include a cooling tower, a chiller, and an air-cooled radiator.

[0037] Here, when a hole is opened in the portion of the circulation flow path 71 (including the cooler 4) located inside the container 2, the insulating gas filled in the container 2 passes through the hole and dissolves into the cooling water. At this time, the higher the pressure inside the container 2, the more easily the insulating gas dissolves in the cooling water. However, in this embodiment, because the circulation flow path 71 is closed (a closed loop), even if the insulating gas dissolves in the cooling water, leakage of the insulating gas to the outside is suppressed.

[0038] A pump 75 is provided in the circulation flow path 71. The cooling water moves along the circulation flow path 71 by the pump 75. In this embodiment, the cooling water flows through the cooler 4, one on-off valve 76, the expansion tank 73, the cooling unit 72, and the other on-off valve 76 in this order by the pump 75. However, in the present invention, the flow direction of the cooling water is not particularly limited. The pump 75 is disposed between the expansion tank 73 and the downstream on-off valve 76 of the pair of on-off valves 76 in the flow direction of the cooling water, more specifically, between the expansion tank 73 and the cooling unit 72.

[0039] (Expansion Tank 73) The expansion tank 73 is a tank for absorbing the expansion of the cooling water. The expansion tank 73 is an open-to-atmosphere type expansion tank 73. That is, the expansion tank 73 according to this embodiment is open to the atmosphere as shown in FIG. 4. The expansion tank 73 has an opening above the liquid level of the cooling water. An exhaust path 77 is connected to the opening of the expansion tank 73, and the inside of the expansion tank 73 is open to the atmosphere via the exhaust path 77.

[0040] If insulating gas is dissolved in the cooling water and the cooling water accumulates in the expansion tank 73, the insulating gas will be released from the cooling water. Because the expansion tank 73 is open to the atmosphere, the insulating gas will try to escape to the outside through the exhaust path 77. Therefore, in this embodiment, an exhaust valve 78 is provided in the exhaust path 77, and by closing the exhaust valve 78 as needed, it is possible to prevent the insulating gas from leaking to the outside.

[0041] (Gas Sensor 74) The gas sensor 74 is a sensor that is sensitive to the insulating gas. Examples of the gas sensor 74 include a semiconductor gas sensor, a catalytic combustion gas sensor, a constant-potential electrolysis gas sensor, a galvanic cell gas sensor, a zirconia gas sensor, a thermal linear semiconductor gas sensor, an infrared absorption gas sensor, and an ultraviolet absorption gas sensor. The type of gas sensor 74 is appropriately selected depending on the insulating gas.

[0042] The gas sensor 74 is provided so as to come into contact with the gas discharged from the expansion tank 73. As shown in FIG. 4, the gas sensor 74 according to this embodiment is provided in a branch path branched off from the exhaust path 77. However, in the present invention, the gas sensor 74 may also be provided inside the exhaust path 77. Furthermore, if the exhaust path 77 is not provided, the gas sensor 74 may be provided at the opening of the expansion tank 73 or inside the expansion tank 73. The gas sensor 74 outputs an electric signal (sensor signal) generated by detection to the control device 8.

[0043] It is preferable that a moisture removal filter be provided in the exhaust path 77 upstream of the gas sensor 74. This makes it possible to protect the gas sensor 74 from moisture from the expansion tank 73.

[0044] (Exhaust valve 78) The exhaust valve 78 is provided in the exhaust path 77 and is configured to be able to open and close the exhaust path 77. Examples of the exhaust valve 78 include a solenoid valve and an electric valve. The exhaust valve 78 is controlled by a control unit of the control device 8. In the control device 8, the control unit that controls the exhaust valve 78 may be referred to as the "exhaust valve control unit 81." When the gas sensor 74 detects insulating gas, the exhaust valve control unit 81 controls the exhaust valve 78 to close. Therefore, even if insulating gas dissolves in the cooling water, the gas sensor 74 detects it, and the exhaust valve 78 can be automatically closed.

[0045] The gas sensor 74 is provided in the exhaust path 77 between the expansion tank 73 and the exhaust valve 78. Therefore, the insulating gas passing through the exhaust path 77 is detected by the gas sensor 74 before passing through the exhaust valve 78. As a result, by operating the exhaust valve 78 in response to detection by the gas sensor 74, it is possible to prevent the insulating gas from escaping from the exhaust path 77 into the atmosphere.

[0046] (Shut-off valve 76) As shown in FIG. 1 , the on-off valves 76 are provided on both sides of the cooler 4 in the circulation flow path 71. The on-off valves 76 are configured to open and close the circulation flow path 71. Examples of the on-off valves 76 include a solenoid valve and an electric valve. The on-off valves 76 are controlled by a control unit of the control device 8. In the control device 8, the control unit that controls the on-off valves 76 may be referred to as the "on-off valve control unit 82." When the gas sensor 74 detects insulating gas, the on-off valve control unit 82 controls both of the pair of on-off valves 76 to close. Therefore, when insulating gas is detected in the cooling water, the flow in the circulation flow path 71 can be immediately stopped, and the cooling water containing dissolved insulating gas can be prevented from newly entering the expansion tank 73. Note that if cooling water containing dissolved insulating gas continues to newly enter the expansion tank 73, the concentration of insulating gas in the cooling water stored in the expansion tank 73 increases, resulting in increased gas treatment costs. However, in this embodiment, as described above, it is possible to prevent cooling water with dissolved insulating gas from newly entering the expansion tank 73, thereby preventing the concentration of insulating gas in the cooling water in the expansion tank 73 from increasing, and reducing gas processing costs.

[0047] (Control device 8) The control device 8 controls the opening and closing operations of the pair of on-off valves 76 and exhaust valve 78. The control device 8 includes an on-off valve control unit 82 and an exhaust valve control unit 81. The on-off valve control unit 82 and the exhaust valve control unit 81 are mainly composed of a processor and memory as hardware. The functions of the on-off valve control unit 82 and the exhaust valve control unit 81 are realized by the processor executing a program recorded in the memory. The program may be pre-recorded in the memory, or may be provided via a telecommunications line, or may be recorded and provided on a non-transitory recording medium such as a memory card, optical disk, or hard disk drive. The processor is composed of one or more electronic circuits including a semiconductor integrated circuit (IC) or a large-scale integrated circuit (LSI). The multiple electronic circuits may be integrated into a single chip or distributed across multiple chips.

[0048] <Effects> As described above, the voltage device of the first aspect comprises a container 2 filled with insulating gas, equipment 3 arranged in the container 2, a cooler 4 housed in the container 2, a ring-shaped circulation flow path 71 connected to the cooler 4, an expansion tank 73 provided in the circulation flow path 71, and a gas sensor 74 provided in contact with the gas coming out of the expansion tank 73 to detect the insulating gas.

[0049] According to this embodiment, since the cooling water can be made to flow through the annular flow path, even if the insulating gas in the container 2 dissolves in the cooling water, the insulating gas can be prevented from leaking to the outside. In addition, the occurrence of deterioration or damage to the cooler 4, which is the cause of the insulating gas dissolving, can be detected by the gas sensor 74.

[0050] In the voltage device of the second aspect, in the first aspect, an exhaust path 77 that leads to the inside of the expansion tank 73 and is open to the atmosphere, an exhaust valve 78 that is provided in the exhaust path 77 and can open and close the exhaust path 77, and an exhaust valve control unit 81 that controls the exhaust valve 78 to close when the gas sensor 74 detects insulating gas.

[0051] According to this embodiment, when the insulating gas is dissolved in the cooling water, the exhaust valve 78 can be closed to prevent the insulating gas from leaking from the expansion tank 73 .

[0052] In the voltage device according to the third embodiment, in the second embodiment, gas sensor 74 is provided in exhaust passage 77 between expansion tank 73 and exhaust valve 78.

[0053] According to this embodiment, the insulating gas passing through the exhaust path 77 is detected by the gas sensor 74 before passing through the exhaust valve 78. As a result, by operating the exhaust valve 78 in response to detection by the gas sensor 74, it is possible to prevent the insulating gas from escaping from the exhaust path 77 into the atmosphere.

[0054] The voltage device according to the fourth aspect, in any one of the first to third aspects, further includes a pair of on-off valves 76 provided on both sides of the cooler 4 in the circulation flow path 71, and an on-off valve control unit 82 that controls both of the pair of on-off valves 76 to close when the gas sensor 74 detects insulating gas.

[0055] According to this embodiment, when it is detected that insulating gas is dissolved in the cooling water, the flow in the circulation flow path 71 can be immediately stopped, and cooling water with dissolved insulating gas can be prevented from newly entering the expansion tank 73. As a result, it is possible to prevent the concentration of insulating gas in the cooling water in the expansion tank 73 from increasing, thereby reducing gas treatment costs.

[0056] In the voltage device according to the fifth aspect, in any one of the first to fourth aspects, the cooler 4 includes a cooling fin that cools the space inside the container 2 as the object to be cooled.

[0057] According to this embodiment, the space inside the container 2 can be cooled effectively.

[0058] A cooling water circulation device 7 according to a sixth aspect is used in a voltage device including a container 2 filled with an insulating gas, a device 3 arranged in the container 2, and a cooler 4 housed in the container 2. The cooling water circulation device 7 includes an annular circulation flow path 71 connected to the cooler 4, an expansion tank 73 provided in a portion of the circulation flow path 71 outside the container 2, and a gas sensor 74 provided in contact with gas coming out of the expansion tank 73 to detect the insulating gas.

[0059] According to this embodiment, since the cooling water can be made to flow through the annular flow path, even if the insulating gas in the container 2 dissolves in the cooling water, the insulating gas can be prevented from leaking to the outside. Furthermore, the dissolved insulating gas can be detected by the gas sensor 74. Furthermore, such a cooling water circulation device 7 can be attached to an existing voltage device.

[0060] <Modification> The above embodiment is merely one of various embodiments of the present invention. The embodiment can be modified in various ways depending on the design, etc., as long as the object of the present invention can be achieved. Modifications of the embodiment are listed below. The modifications described below can be applied in appropriate combinations.

[0061] In the above embodiment, the electron beam irradiation device 10 is a scanning type, but in the present invention, a non-scanning type (area type) electron beam irradiation device may also be used.

[0062] The voltage device according to the above embodiment may be a new voltage device, or the cooling water circulator 7 may be newly installed in an existing voltage device.

[0063] The device 3 in the above embodiment is the accelerator 31, but there are no particular limitations as long as it is a device that generates heat when supplied with electricity. A gas circuit breaker also generates heat due to arc discharge that occurs when breaking a circuit, and is therefore included in the "device 3" in this specification.

[0064] In the above embodiment, when insulating gas is detected by the gas sensor 74, the pair of on-off valves 76 and the exhaust valve 78 are controlled to close, but in the present invention, an alert may be given that insulating gas has dissolved in the gas. There are no particular limitations on the alert method, and examples include alerting by a buzzer sound, a flashing warning light, a warning message displayed on a monitor, and vibration.

[0065] In this specification, expressions accompanied by "approximately", such as "approximately parallel" or "approximately perpendicular", may be used. For example, "approximately parallel" means that the state is substantially "parallel", and includes not only a strictly "parallel" state but also an error of a few degrees. The same applies to other expressions accompanied by "approximately".

[0066] Furthermore, in this specification, expressions such as "end" and "edge" are used that are distinguished by the presence or absence of "... part." For example, "edge" means the end of an object, while "edge" means a region having a certain range that includes the "edge." Any point within a certain range that includes the edge is considered to be an "end." The same applies to other expressions that include "... part." [Explanation of symbols]

[0067] 2 containers 3 equipment 4 Cooler 7 Cooling water circulation system 71 Circulation flow path 72 Cooling section 73 Expansion Tank 74 Gas Sensor 76 On-off valve 77 Exhaust duct 78 Exhaust valve 81 Exhaust valve control section 82 On-off valve control section

Claims

1. a container filled with an insulating gas; a device disposed in the container and generating heat upon receiving electricity; a cooler housed in the container that cools an object to be cooled by heat exchange with cooling water; a circulation flow path connected to the cooler, the circulation flow path being formed in a ring shape so that the cooling water circulates, and the circulation flow path being provided with a cooling unit that cools the cooling water in a portion outside the container; an expansion tank provided in a portion of the circulation flow path outside the container and open to the atmosphere; a gas sensor that is provided in contact with the gas discharged from the expansion tank and detects the insulating gas. Voltage device.

2. an exhaust passage communicating with the interior of the expansion tank and open to the atmosphere; an exhaust valve provided in the exhaust path and capable of opening and closing the exhaust path; an exhaust valve control unit that controls the exhaust valve to close when the gas sensor detects the insulating gas, The voltage device of claim 1 .

3. The gas sensor is provided in the exhaust path between the expansion tank and the exhaust valve. The voltage device of claim 2 .

4. a pair of on-off valves provided on both sides of the cooler in the circulation flow path; an on-off valve control unit that controls the pair of on-off valves to close when the gas sensor detects the insulating gas. A voltage device according to any one of claims 1 to 3.

5. The cooler includes a cooling fin that cools the space within the container as the cooling target.

5. A voltage device according to any one of claims 1 to 4.

6. a container filled with an insulating gas; a device disposed in the container and generating heat upon receiving electricity; a cooler housed in the container that cools an object to be cooled by heat exchange with cooling water; A cooling water circulator for use in a voltage device comprising: a circulation flow path connected to the cooler, the circulation flow path being formed in a ring shape so that the cooling water circulates, and the circulation flow path being provided with a cooling unit that cools the cooling water in a portion outside the container; an expansion tank provided in a portion of the circulation flow path outside the container and open to the atmosphere; a gas sensor that is provided in contact with the gas discharged from the expansion tank and detects the insulating gas. Cooling water circulation device.

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