Gas leakage measuring system and gas leakage measuring method for gas insulation apparatus

Abstract

To provide a gas leakage measuring system and a gas leakage measuring method for a gas insulation apparatus that can measure gas leakage from a gas insulation apparatus in a short time in a factory test or a site installation test.SOLUTION: A gas leakage measuring system for a gas insulation apparatus comprises: a gas pressure sensor for measuring the gas pressure of gas filled into a sealed container of the gas insulation apparatus; a temperature sensor for measuring the temperature of the gas; and a gas leakage determination device that measures leakage of the gas from a measurement signal from the gas pressure sensor and a measurement signal from the temperature sensor. The gas leakage measuring system has a gas temperature change prevention mechanism for preventing a change in the temperature of the gas.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] An embodiment of the present invention relates to a gas leakage measurement system and a gas leakage measurement method for gas-insulated equipment. [Background technology]

[0002] Gas-insulated equipment has traditionally used high-pressure SF6 gas as the insulating medium. However, due to the high global warming potential of SF6 gas, development is underway for gas-insulated equipment that uses naturally occurring gases such as a mixture of CO2 and O2, nitrogen, or dry air as the insulating medium.

[0003] The conventional method for gas leak testing of gas-insulated equipment using SF6 gas at factories or on-site installation is to fill the equipment with SF6 gas up to the rated gas pressure, and then use the accumulation method with a gas leak detector at gas-tight locations such as connections and gas piping.

[0004] On the other hand, gas leak tests for gas-insulated equipment that uses the above-mentioned naturally occurring gases as an insulating medium are conducted using the accumulation method during factory or on-site installation, just as with gas-insulated equipment that uses SF6 gas. However, unlike SF6 gas, it is difficult to distinguish between the gas used and the atmosphere, so a different test gas that is easy to detect (such as helium gas) is sealed inside the gas-insulated equipment container before checking for gas leaks. After that, the sealed test gas is removed and the naturally occurring gas to be used in the product is sealed in. This poses the problem of lengthening the time required for gas leak tests and the duration of on-site construction.

[0005] JEC2390-2023 specifies that the leakage rate of mixed gases containing SF6 gas must be 0.5 vol% or less per year, and that of mixed gases not containing SF6 gas must be 1 vol% or less per year.

[0006] One technique for measuring such minute gas leaks over a long period of time is the slow gas leak measurement method, in which a gas pressure sensor is attached to gas-insulated equipment and minute gas leaks are detected by changes in gas pressure.

[0007] A conventional example of slow gas leak monitoring using a gas pressure sensor is the technology described in Patent Document 1. This technology corrects the pressure within a gas compartment to the pressure at a predetermined reference temperature based on information obtained from a gas pressure sensor attached to each gas compartment of gas-insulated equipment and a temperature sensor that measures the temperature on the tank surface, and determines whether a gas leak has occurred. Furthermore, the technology described in Patent Document 2 improves the accuracy of temperature-dependent gas pressure correction by performing a preliminary test before measuring a slow gas leak and incorporating the temperature information measured in the preliminary test into a gas pressure correction function. [Prior art documents] [Patent documents]

[0008] [Patent Document 1] Patent No. 6805346 [Patent Document 2] Japanese Patent Application Publication No. 2023-161976 Summary of the Invention [Problem to be solved by the invention]

[0009] In the slow gas leak measurement method described in Patent Document 1, gas pressure fluctuates significantly depending on gas temperature, making it difficult to determine whether a gas leak has occurred based on instantaneous measurements. Instead, gas pressure and temperature must be measured over a long period of time to obtain trends in pressure change and determine whether a gas leak has occurred. Furthermore, the method described in Patent Document 2 incorporates temperature information measured in advance in a preliminary test into the gas pressure correction function, which makes slow gas leak measurement time-consuming and lengthens the test time. Therefore, this method cannot be used in factory tests or on-site installation tests, which require a quick determination.

[0010] The present invention has been made in response to the above-mentioned conventional circumstances, and its object is to provide a gas leak measurement system and a gas leak measurement method for gas-insulated equipment that can measure gas leaks from gas-insulated equipment in a short period of time during factory tests or on-site installation tests. [Means for solving the problem]

[0011] A gas leak measurement system for gas-insulated equipment according to an embodiment includes a gas pressure sensor for measuring the gas pressure of the gas filled in the sealed container of the gas-insulated equipment, a temperature sensor for measuring the temperature of the gas, and a gas leak determination device for measuring the gas leak from the measurement signal of the gas pressure sensor and the measurement signal of the temperature sensor, and is characterized by having a gas temperature change suppression mechanism for suppressing changes in the temperature of the gas. [Effects of the Invention]

[0012] According to the embodiments of the present invention, it is possible to provide a gas leakage measurement system and a gas leakage measurement method for gas-insulated equipment that can measure gas leakage from gas-insulated equipment in a short time during factory testing or on-site installation testing. [Brief explanation of the drawings]

[0013] [Figure 1] 1 is a diagram showing a schematic configuration of a gas leakage measurement system for gas-insulated equipment according to a first embodiment; [Figure 2] FIG. 10 is a diagram showing a schematic configuration of a gas leakage measurement system for gas-insulated equipment according to a second embodiment. [Figure 3] FIG. 10 is a diagram showing a schematic configuration of a gas leakage measurement system for gas-insulated equipment according to a third embodiment. [Figure 4] FIG. 10 is a diagram showing a schematic configuration of a gas leakage measurement system for gas-insulated equipment according to a fourth embodiment. [Figure 5] FIG. 10 is a diagram showing a schematic configuration of a gas leakage measurement system for gas-insulated equipment according to a fifth embodiment. [Figure 6]FIG. 10 is a diagram showing a schematic configuration of a gas leakage measurement system for gas-insulated equipment according to a sixth embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0014] Hereinafter, a gas leakage measurement system and a gas leakage measurement method for gas-insulated equipment according to an embodiment will be described with reference to the drawings.

[0015] (First embodiment) FIG. 1 is a diagram showing a schematic configuration of a gas leakage measurement system 200 for gas-insulated equipment according to the first embodiment.

[0016] 1 is a device for determining whether or not a gas leak has occurred in gas-insulated equipment 100 when no voltage is applied. Gas-insulated equipment 100 houses equipment such as a circuit breaker inside tank 100a, which is an airtight container, and SF gas or a naturally occurring gas (e.g., CO / O mixed gas, nitrogen, dry air, etc.) is sealed inside at a predetermined pressure as an insulating medium.

[0017] The gas-insulated equipment gas leak measurement system 200 includes a gas leak determination device 201, a gas pressure sensor 202, a temperature sensor 203, and a shield 204 as a gas temperature change suppression mechanism. The gas leak determination device 201 also includes a measurement processing unit 201a and an alarm generating unit 201b.

[0018] The gas pressure sensor 202 is installed via a pipe in the gas insulated equipment 100. The gas pressure sensor 202 outputs information about the measured gas pressure inside the tank 100a of the gas insulated equipment 100 to the measurement processing unit 201a of the gas leak determining device 201.

[0019] The temperature sensor 203 is installed to detect the temperature of the surface of the tank 100a of the gas insulated equipment 100, and indirectly detects the temperature of the gas inside the tank 100a via the tank 100a. The temperature sensor 203 outputs the measured temperature information to the measurement processing unit 201a of the gas leak determining device 201.

[0020] The gas leak determination device 201 corrects the input gas pressure information and temperature information to a gas pressure at a predetermined reference temperature in the measurement processing unit 201a, and determines whether or not a gas leak has occurred in the gas insulated equipment 100. If it is determined that a gas leak has occurred, an alarm is issued from the alarm generation unit 201b.

[0021] The shield 204 serving as a gas temperature change suppression mechanism is installed so as to cover the entire periphery of the gas insulated apparatus 100. This shield 204 can be suitably made of a resin cloth, such as that used for tents, so as to suppress sunlight and drafts on the gas insulated apparatus 100. Since the temperature of the gas insulated apparatus 100 is affected by sunlight and drafts, installing the shield 204 covering the gas insulated apparatus 100 suppresses variations in the temperature (gas temperature) of the gas insulated apparatus 100, and enables accurate measurement of slow gas leaks in a short period of time (for example, about half a day). The shield 204 covering the gas insulated apparatus 100 may be something other than a curtain, such as a plate, as long as it can block sunlight and drafts to some extent.

[0022] (Second embodiment) Next, the configuration of a gas-insulated equipment gas leak measurement system 200a according to a second embodiment will be described with reference to FIG.

[0023] In the second embodiment, a heating device 205 is provided as a gas temperature change suppression mechanism around the gas insulated apparatus 100. This heating device 205 controls the temperature of the gas insulated apparatus 100 to a constant temperature, thereby suppressing variations in the temperature (gas temperature) of the gas insulated apparatus 100 and enabling slow gas leaks to be measured accurately in a short time.

[0024] As the heating device 205, for example, a heat exchanger is wrapped around the outside of the gas insulated apparatus 100, and hot water that is higher than room temperature is passed through the heat exchanger using a hot water chiller or the like, thereby heating the gas insulated apparatus 100 to a temperature higher than room temperature. Note that as the heating device 205, in addition to a hot water chiller, other heating mechanisms, for example, an electric heater, can also be used.

[0025] (Third embodiment) Next, with reference to FIG. 3, the configuration of a gas-insulated equipment gas leak measurement system 200b according to a third embodiment will be described.

[0026] In the third embodiment, a cooling device 206 is provided as a gas temperature change suppression mechanism around the gas insulated apparatus 100. This cooling device 206 controls the temperature of the gas insulated apparatus 100 to a constant temperature, thereby suppressing variations in the temperature (gas temperature) of the gas insulated apparatus 100 and enabling slow gas leaks to be measured accurately in a short time.

[0027] The cooling device 206 may be, for example, a heat exchanger wrapped around the outside of the gas insulated equipment 100, and cool the gas insulated equipment 100 to a temperature lower than room temperature by running cold water that is lower than room temperature through the heat exchanger using a cold water chiller or the like. Note that the cooling device 206 may be any cooling mechanism other than a cold water chiller as long as it can cool the gas insulated equipment 100 to a constant temperature.

[0028] (Fourth embodiment) Next, with reference to FIG. 4, the configuration of a gas leakage measurement system 200c for gas-insulated equipment according to a fourth embodiment will be described.

[0029] In the fourth embodiment, an internal conductor 207 and a power supply device 208 are provided as a gas temperature change suppression mechanism. That is, the internal conductor 207 is disposed inside the tank 100a of the gas insulated equipment 100, and the power supply device 208 is connected to the internal conductor 207 so as to pass a constant current.

[0030] In this way, by passing a constant current through the internal conductor 207, the internal conductor 207 is heated, so that the temperature of the gas inside the gas insulated equipment 100 can be controlled to a constant temperature, and slow gas leaks can be measured accurately in a short time. As the power supply device 208, for example, a commonly used power supply for construction work can be used, and either AC or DC can be used.

[0031] (Fifth embodiment) Next, with reference to FIG. 5, the configuration of a gas-insulated equipment gas leak measurement system 200d according to a fifth embodiment will be described.

[0032] In the fifth embodiment, an internal heater 209 and a power supply device 210 are provided as a gas temperature change suppression mechanism. That is, the internal heater 209 is disposed inside the gas insulated equipment 100, and the power supply device 210 is connected to the internal heater 209 so as to supply a constant current thereto.

[0033] In this way, the internal heater 209 is heated by passing a constant current through it, so that the temperature of the gas inside the gas insulated equipment 100 can be controlled to a constant temperature and slow gas leaks can be measured accurately in a short time. The internal heater 209 is installed inside the tank 100a of the gas insulated equipment 100 so that the heat-generating part does not come into contact with the tank 100a, and wiring is drawn out from a manhole or gas piping on the side of the tank 100a and connected to the power supply unit 210.

[0034] (Sixth embodiment) Next, with reference to FIG. 6, the configuration of a gas leakage measurement system 200e for gas-insulated equipment according to a sixth embodiment will be described.

[0035] In the sixth embodiment, when the tank 100a of the gas insulating equipment 100 is long, temperature sensors 203 for detecting the surface temperature of the tank 100a are installed at multiple locations spaced apart in the longitudinal direction of the tank 100a.

[0036] When the tank 100a of the gas insulated equipment 100 is long, there is a concern that the measured temperature may vary greatly due to the effects of sunlight and ventilation. However, with only the configurations of the first to fifth embodiments described above, it is expected that the gas temperature may vary depending on the position of the tank 100a.

[0037] Therefore, in the sixth embodiment, a plurality of temperature sensors 203 are installed in the tank 100a, and temperature information detected by each temperature sensor 203 is output to the gas leak determination device 201, and an average value is calculated. Two or more temperature sensors 203 are installed, but it is preferable to change the installation positions and number depending on the conditions of sunlight and ventilation and the length of the tank 100a of the gas insulated equipment 100. For example, when there is sunlight, it is preferable to install the sensors in a sunny location and a shaded location.

[0038] A gas pressure sensor 202 is installed in the tank 100a via a pipe, and outputs measured internal gas pressure information to a gas leak determination device 201. The gas leak determination device 201 corrects the gas pressure at a predetermined reference temperature based on the average value of the temperature information and the gas pressure information, and determines whether or not a gas leak has occurred in the gas insulated equipment 100. Note that the sixth embodiment can be combined with any of the first to fifth embodiments described above.

[0039] 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, modifications, and combinations 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]

[0040] 100...Gas insulated equipment, 200, 200a, 200b, 200c, 200d, 200e...Gas leak measurement system for gas insulated equipment, 201...Gas leak determination device, 201a...Measurement processing unit, 201b...Alarm generation unit, 202...Gas pressure sensor, 203...Temperature sensor, 204...Shield, 205...Heating device, 206...Cooling device, 207...Inner conductor, 208...Power supply unit, 209...Internal heater, 210...Power supply unit.

Claims

1. a gas pressure sensor for measuring the pressure of the gas filled in the sealed container of the gas-insulated equipment; a temperature sensor for measuring the temperature of the gas; a gas leak determination device that measures the gas leak based on the measurement signal of the gas pressure sensor and the measurement signal of the temperature sensor; A gas leakage measurement system for gas-insulated equipment, comprising: A gas leakage measurement system for gas-insulated equipment, comprising a gas temperature change suppression mechanism for suppressing changes in the temperature of the gas.

2. 2. The gas leakage measurement system for gas-insulated equipment according to claim 1, 10. A gas leakage measurement system for gas-insulated equipment, wherein the gas temperature change suppression mechanism has a shield that covers the sealed container.

3. 2. The gas leakage measurement system for gas-insulated equipment according to claim 1, 10. A gas leakage measurement system for gas-insulated equipment, wherein the gas temperature change suppression mechanism has a heating mechanism for heating the gas.

4. 4. The gas leakage measurement system for gas-insulated equipment according to claim 3, 10. A gas leakage measurement system for gas-insulated equipment, wherein the heating mechanism has a mechanism for supplying hot water to the sealed container.

5. 4. The gas leakage measurement system for gas-insulated equipment according to claim 3, 10. A gas leakage measurement system for gas-insulated equipment, wherein the heating mechanism comprises an internal conductor disposed within the sealed container, and a power source for energizing the internal conductor.

6. 4. The gas leakage measurement system for gas-insulated equipment according to claim 3, 10. A gas leakage measurement system for gas-insulated equipment, wherein the heating mechanism comprises an internal heater disposed within the sealed container, and a power source for energizing the internal heater.

7. 2. The gas leakage measurement system for gas-insulated equipment according to claim 1, 10. A gas leakage measurement system for gas-insulated equipment, wherein the gas temperature change suppression mechanism has a cooling mechanism for cooling the gas.

8. 2. The gas leakage measurement system for gas-insulated equipment according to claim 1, A gas leakage measurement system for gas-insulated equipment, comprising a plurality of the temperature sensors.

9. 9. A gas leakage measuring method for gas-insulated equipment, comprising measuring leakage of a gas filled in a sealed container of the gas-insulated equipment using the gas leakage measuring system for gas-insulated equipment according to claim 1.

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