JP3343524B2 - Gas analyzer in electrical insulating oil - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an improved analyzer for gas components dissolved in electrical insulating oil filled in oil-filled electrical equipment such as a transformer, and more particularly to an improved analyzer for oil-filled electrical equipment. The present invention relates to an apparatus for analyzing gas in electrically insulating oil used for performing deterioration diagnosis and abnormality diagnosis.

[0002]

2. Description of the Related Art Electrical insulating oil is used for oil-filled transformers, reactors,
It is used for oil-filled electrical equipment such as automatic voltage regulators, oil immersion cables, etc., but contains carbon dioxide [CO
₂ ], carbon monoxide [CO], methane [CH ₄ ], hydrogen [H ₂ ], ethane [C ₂ H ₆ ], ethylene [C ₂ H
_4], various gas amount of such acetylene [C ₂ H _2] is important as a barometer indicating the status of deterioration or abnormality of the electric equipment and oil immersion cable. Therefore, it is indispensable to obtain an accurate gas-in-oil analysis value for estimating the state of deterioration of these devices and diagnosing abnormalities.

[0003] As described above, the gas analysis value of the electrical insulation oil of the oil-filled electrical equipment is used as an important index in diagnosing the abnormality of the oil-filled electrical equipment and predicting aging deterioration. That is, in the gas analysis value, hydrogen [H
₂ ], methane [CH ₄ ], acetylene [C ₂ H ₂ ], etc., can detect abnormalities such as partial discharge and overheating inside oil-filled electrical equipment.
Further, from carbon dioxide [CO ₂ ], carbon monoxide [CO], etc., it is possible to infer an abnormality or an aged deterioration state of the insulating paper or the like.

In order to make the above diagnosis and prediction, it is necessary to accurately grasp the analysis value of the gas in the electrically insulating oil. The device for analyzing the gas in an electrically insulating oil (hereinafter, referred to as gas in oil) generally includes a gas-in-oil extraction device for extracting gas in oil into the air (hereinafter, referred to as an extraction device), and an extracted gas. And an analyzer using a gas chromatograph for qualitative and quantitative determination.

[0005] The gas chromatograph has been completed as an analyzer, and can be easily calibrated with a standard gas, and has very high analysis accuracy without any particular problem.

[0006] On the other hand, various types of extraction devices have been proposed. Examples of commonly used extraction devices include, for example, a trickle vacuum, a Teppler pump vacuum, a vacuum piston, and the like. A method in which gas in oil is statically extracted, and argon [A]
r], helium [He], or the like, and a method of injecting an inert gas to forcibly drive out and extract gas in oil.

[0007]

In the above-described gas-in-oil extraction method, in the static extraction method, if the concentration and detection amount of gas-in-oil are different, the extraction rate of components in gas-in-oil is low. As a result, the extraction rate itself becomes low due to the large fluctuation and the analysis value is corrected using the extraction rate correction coefficient each time, so the analysis of gas in oil takes time and effort. In addition, there were problems with the reliability of the analysis values. In addition, during the analysis work,
In extraction devices using mercury, the environment, especially
Attention was required in the work environment.

In the method of forcibly removing and extracting oil-in-gas using an inert gas, when extracting gas-in-oil, for example, the electrical insulating oil, which is a sample, is extracted while in contact with air. When injected into a bottle, in this state, the inside of the evacuated pipe is sent out to the gas chromatograph while being pushed by the inert gas. As a result, a large amount of air (nitrogen N ₂ and oxygen Due to the mixture of ₂ ), it was difficult to obtain accurate analytical values.

In order to solve this problem, an oil mist trap or a moisture adsorbent for removing impurities in the insulating oil is installed in the middle of the pipe, or the insulating oil is heated by a heating means to extract dissolved gas. However, in this case, the configuration of the extraction device itself is complicated, and the size of the extraction device is increased, thereby increasing the manufacturing cost and complicating the maintenance of the extraction device.

The present invention has been made in view of the above-mentioned various problems, and in oil-filled electrical equipment, the oil-soluble electrical equipment dissolves in electrical insulating oil, which is a variety of decomposition products generated from an insulating material due to internal abnormality of the equipment or aging deterioration. Provide an improved gas analyzer for electric insulating oil that can efficiently extract dissolved gas from electric insulating oil and improve the qualitative and quantitative analysis by gas chromatography quickly and with improved accuracy. Is to do.

[0011]

According to a first aspect of the present invention, there is provided a gas analyzer in an electrically insulating oil, comprising: a container for storing the electrically insulating oil; and a gas supply pipe for supplying a first carrier gas to the container at a constant pressure. A gas storage pipe for storing the dissolved gas extracted from the storage container, a gas flow pipe communicating with the storage pipe for flowing the dissolved gas, and a gas flow pipe for flowing the second carrier gas at a constant pressure. And a solenoid switching valve for switching and connecting the storage gas and distribution pipes of the dissolved gas and the gas flow pipe so as to be able to communicate arbitrarily, and means for reducing the pressure of the storage container and the flow path of the dissolved gas. Gas analysis means for qualitatively and quantitatively analyzing the dissolved gas stored in the gas storage pipe by the second carrier gas; and calculating the gas component of the dissolved gas analyzed by the gas analysis means to perform oil-injection. Device error It was constituted by a data processing means for storing reference data necessary for the reduction determination retrievable in.

According to a second aspect of the present invention, in the gas analyzer for an electrically insulating oil according to the first aspect, the solenoid-operated directional control valve is configured to connect the second carrier gas to the inflow side of the dissolved gas. With the gas flow pipe through which the gas flows, a plurality of electrically insulating oil storage containers were connected in parallel via the gas flow pipe, and the outflow side of the dissolved gas was built in the gas analyzer. The detector was configured to be individually connected to a predetermined gas detector via the gas flow pipe.

According to a third aspect of the present invention, in the gas analyzer for an electrically insulating oil according to the second aspect of the present invention, the solenoid-operated directional control valve is provided for dissolving gas stored in the gas storage tube for each gas storage tube. It was arranged so that it could be evenly stored.

According to a fourth aspect of the present invention, in the electric insulating oil-in-oil gas analyzer according to the second aspect, the solenoid-operated directional control valve is provided for dissolving gas stored in the gas storing pipe for each gas storing pipe. It was arranged so that it might be stored unevenly.

According to a fifth aspect of the present invention, in the gas analyzer for an electrically insulating oil according to the second aspect of the present invention, the gas distribution pipe is configured to have a smaller diameter than a gas storage pipe.

According to a sixth aspect of the present invention, in the gas analyzer for an electrically insulating oil according to the first aspect of the present invention, the flow path and the storage portion of the dissolved gas are each for extracting and flowing the dissolved gas. And a heating means for maintaining a predetermined temperature suitable for the temperature.

According to the present invention, when the dissolved gas extracted from the electric insulating oil is sent to a gas chromatograph as described above, the gas is sent using the pressure of a carrier gas which does not adversely affect the dissolved gas. Has been
Since no special mechanical extraction device such as a Tepler pump system, a piston system, or a bellows system is required to deliver the dissolved gas, the system for extracting the dissolved gas can be simplified.

In the present invention, the dissolved gas is extracted in a uniform or non-uniform state. Therefore, when the dissolved gas is subjected to qualitative / quantitative analysis using a gas chromatograph. This is convenient because the dissolved gas can always be analyzed with an optimal extraction amount (extraction rate).

Further, since the gas circulation pipe through which the extracted dissolved gas flows is smaller in diameter than the gas storage pipe for temporarily storing the dissolved gas, the diffusion of the dissolved gas is suppressed and the extraction rate is increased. Therefore, it is possible to favorably maintain and expand the sensitivity of analysis by gas chromatography, which is convenient.

Moreover, since the flow path and the storage portion of the dissolved gas are always kept at a predetermined temperature, the viscosity of the electric insulating oil is kept good, and the dissolved gas is smoothly and smoothly condensed. It can be delivered without reducing the amount of extraction.

[0021]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to FIGS. First, FIG. 1 is a schematic cross-sectional view of an oil-filled electric device (hereinafter, referred to as a transformer) 1 such as a transformer using electric insulating oil (hereinafter, referred to as insulating oil), in which a coil is attached to a conventionally known iron core. The transformer main body 2 formed by winding is housed in a case 3, and a predetermined amount of electric insulating oil 4 is filled and sealed. Reference numeral 5 denotes an oil drain cock provided at a lower portion of the case 3 for extracting insulating oil in the case 3.

A syringe 6 shown in FIG. 2 is capable of extracting a predetermined amount of the insulating oil 4 in the case 3 without substantially exposing the insulating oil 4 to the atmosphere. The operation of extracting the insulating oil 4 by the syringe is similar to the operation of a syringe. Then, the insulating oil 4 is extracted.

Next, in FIGS. 3 and 4, reference numeral 11 denotes a gas-in-oil analyzer of the present invention.
As shown in FIG. 1, means 1 for extracting dissolved gas dissolved in insulating oil
2, a gas storage means 21 for temporarily storing (storing) the extracted dissolved gas, an analysis means (gas chromatograph) 31 for qualitatively and quantitatively analyzing the stored dissolved gas, and a detection signal sent from the analysis means 31. Performs arithmetic processing to store, display, and store reference data necessary for performing abnormality diagnosis and deterioration diagnosis.
And a data storage means 35 for acquiring.

Next, each means 12, 21, 31, 35 of the gas analyzer 11 will be described. First, the configuration of the extraction unit 12 will be described. In FIG. 3, 1
Reference numeral 3 denotes an insulating oil storage container (hereinafter referred to as an oil collecting bin) for storing the insulating oil 4 extracted from the transformer 1, and 14 denotes an oil collecting bin 13.
An insulating oil injection pipe for injecting the insulating oil 4 therein, which is formed so that the syringe 6 can be attached in a substantially airtight state via a valve (not shown), and is connected to the body of the oil collecting bin 13 in a horizontal state. ing. Reference numeral 15 denotes a discharge pipe of the oil collecting bin 13, and the used insulating oil 4 in the oil collecting bin 13 is discharged to a waste oil drain 17 via a discharge valve 16.

Reference numeral 18 denotes a gas supply pipe for injecting a first carrier gas for bubbling (for example, a gas such as helium He, argon Ar or the like) as fine bubbles into the oil collecting bin 13 at a constant pressure. The spout is provided at the upper end of the oil sampling bin 13 with such a length that the injection port can be immersed in the insulating oil 4 in the oil sampling bin 13. Reference numeral 20 denotes a small-diameter gas flow pipe through which a dissolved gas extracted from a dissolved component in the insulating oil 4 flows. As shown in FIG. 3, the gas flow pipe 20 has a plurality of electromagnetic switching valves (for example, 6 In this example, it is 3
) 22, 22 a, 22 b and the oil sampling bin 13 are connected in parallel (individually connected using three flow pipes 20) and in a communicable state.

The electromagnetic switching valves 22 to 22b are
A gas supply pipe 18 constituting a flow path of the dissolved gas;
A gas flow pipe 23 for flowing the carrier gas through the gas analysis means 31 at a constant pressure, and a gas storage pipe 24 for temporarily storing dissolved gas near the electromagnetic switching valves 22 to 22b.
Thus, the dissolved gas storage means 21 is constituted. Note that a pneumatic or hydraulic switching valve may be used instead of the electromagnetic switching valve.

In the gas storage means 21, the dissolved gas is collected and stored in each gas storage pipe 24 by the electromagnetic switching valves 22 to 22b, and the stored dissolved gas is analyzed by the gas analysis means 31. For analysis,
The electromagnetic switching valves 22 to 22b are switched by a command signal from a control device (not shown) to connect the gas flow pipe 23 through which the second carrier gas flows and the gas storage pipe 24, thereby dissolving the dissolved gas into the second gas. The gas can be sent to the gas analyzer 31 via the second gas flow pipe 23a at the pressure of the carrier gas.

In FIG. 3, reference numeral 25 denotes a pressure gauge attached to the end position of the gas flow pipe 20, and reference numeral 26 denotes a vacuum pump. The vacuum pump 26 extracts a dissolved gas from the insulating oil 4 beforehand. The flow path of the dissolved gas, including the oil sampling bin 13, is depressurized at a predetermined pressure. 27 is a switching cock. The dissolved gas extracting means 12 and the gas storing means 21 are provided with a heat retaining means (about 5 mm) for preventing the dissolved gas extracted from the insulating oil 4 from being condensed in the flow path.
0 to 60 ° C.) 28, and the heat retaining means 28 may be, for example, to supply hot air into the enclosed housing,
It may be formed by known technical means such as attaching a heat source such as a heater.

Further, in the gas storage means 21, the gas flow pipes 23 and 23a are formed to have a smaller diameter than the gas storage pipe 24, and the ratio is such that the diameter of the gas flow pipes 23 and 23a is one. In this case, the gas storage tube 24 is formed to have a diameter two to four times as large. This is achieved by reducing the diameter of the gas flow pipes 23, 23a with respect to the gas storage pipe 24.
In order to prevent the dissolved gas from being condensed, liquefied or diffused, to collect and store it in the gas storage tube 24 promptly and in a selected state, and to perform gas analysis and detection efficiently by the gas analysis means 31. .

Next, the gas analyzing means 31 will be described. The gas analyzing means 31 generally uses, for example, a gas chromatograph, and its configuration performs qualitative / quantitative analysis of a dissolved gas. That is, a thermal conductivity detector (TCD) and a flame ionization detector (FID) having a function of detecting each gas component in the dissolved gas with a detector and converting the detection result into an electric signal are provided. I have.

And, the thermal conductivity detector (TCD)
Is generally used when analyzing and detecting inorganic gases.
Therefore, hydrogen [H_Two ], Oxygen [O_Two ], Nitrogen [N_Two ]gas
And so on. In addition, hydrogen flame ionization detector (FID)
Is used for the analysis and detection of hydrocarbon gases.
Carbonized [CO], carbon dioxide [CO_Two ], Methane [CH
_Four ], Ethane [C_Two H₆ ], Ethylene [C_Two H_Four ], A
Cetylene [C_Two H_Two ] Gas is the target.

The detectors (TCD) and (FID) are:
The analysis is performed by introducing and passing the dissolved gas, and the analysis result is converted into an output voltage corresponding to the gas detection time for each target gas. That is, the analyzed gas is converted into an output voltage for each gas component.

Subsequently, the data storage means 35 is provided with a normal arithmetic unit, a display device, a printer and the like. The data storage means 35 analyzes the detection signal (output power) detected by the gas analysis means 31. After performing arithmetic processing, the processed data is displayed on a display device as necessary,
It is possible to record by launching with a printer.
Further, by providing a storage device, a function is provided for storing reference data necessary for grasping deterioration diagnosis and abnormality judgment, and performing deterioration / abnormal diagnosis based on this data.

Next, the operation will be described. First, as shown in FIG. 3, the dissolved gas flows through the gas flow pipes 23 and 23a through which the second carrier gas flows, according to a command signal from a control device (not shown). The switching is performed in a direction that does not communicate with the gas flow pipe 20. In this state, the injection valve 19 of the gas supply pipe 18 is
After the valve (not shown) of the insulating oil injection pipe 14 is closed, the switching cock 27 is opened and the vacuum pump 26 is started. By starting the vacuum pump 26, the oil sampling bin 13 through which the dissolved gas flows, the gas flow pipe 20, the gas storage pipe 2, and the like.
4 is decompressed to a predetermined degree of vacuum (for example, 133 Pa or less).

When the flow path of the dissolved gas is reduced to a predetermined reduced pressure, the switching cock 27 is closed. Subsequently, as shown in FIG. 2, a second oil drain cock 5a having a small-diameter exhaust pipe 7 for wiping insulating oil is mounted on a flange of an oil drain cock 5 provided at a lower portion of the case 3 of the transformer 1. Install oil tightly.
Thereafter, the oil drain cocks 5 and 5a are sequentially opened with the small diameter oil jet cylinder at the tip of the syringe 6 closely fitted to the discharge pipe 7. When the oil drain cocks 5 and 5a are opened, the insulating oil 4 in the case 3 flows out to the discharge pipe 7;
Are tightly fitted, the insulating oil 4
Does not leak to the outside.

In this state, the piston 6a of the syringe 6 is gradually retracted in the manner of a syringe, and the insulating oil 4 is injected into the container 6b of the syringe 6 with almost no contact with the atmosphere, for example, 5 to 10 ml. When the insulating oil 4 is injected into the syringe 6, the oil drain cocks 5 and 5 a are closed, and the oil jet cylinder at the tip of the syringe 6 is pulled out from the discharge pipe 7, thereby completing the oiling of the insulating oil 4. Next, when a predetermined amount of the insulating oil 4 is collected by the syringe 6, the oil cylinder of the syringe 6 is oil-tightly fitted to the insulating oil injection pipe 14 of the oil collecting bin 13. Subsequently, the valve (not shown) of the insulating oil injection pipe 14 is opened, and the piston rod 6a of the syringe 6 is pushed so that the insulating oil 4 in the container 6b is fixedly injected into the oil sampling bottle 13 without almost contacting the outside air. .

As described above, the insulating oil 4
Is filled in the oil sampling bin 13, the insulating oil injection pipe 14 is closed by closing a valve (not shown) to hermetically seal the oil sampling bin 13.
In this case, that is, the injection of the insulating oil 4 into the oil sampling bin 13
Since the flow path of the dissolved gas, such as the oil sampling bin 13, is previously held under reduced pressure by the vacuum pump 26, the insulating oil 4
Can be smoothly filled into the oil sampling bottle 13. In addition,
In this state, the drain valve 16 and the switching cock 27 are closed in advance.

Subsequently, the injection valve 19 is opened and the first
Carrier gas (for example, helium gas He) is ejected into the insulating oil 4 in the oil sampling bin 13 through the gas supply pipe 18 at a pressure sufficient to extract a predetermined gas pressure (a dissolved component in the insulating oil 4). .

By injecting the first carrier gas into the insulating oil 4 in the oil sampling bin 13 as described above, the insulating oil 4 sealed in the oil sampling bin 13 is extracted from the transformer 1 almost without contacting outside air. The dissolved components therein are extracted as dissolved gas. This extraction method is generally called a bubbling method. The dissolved gas extracted from the insulating oil is sequentially fed to the gas storage means 21 shown in FIG. 3, and stored in the gas storage pipe 24 provided in the middle of the pipe.

In general, the concentration of the dissolved gas to be extracted increases to a maximum when about one minute has passed from the start, and thereafter the concentration decreases. The extraction rate Y of the dissolved gas from the insulating oil 4 is generally calculated as follows.

[0041]

(Equation 1)

Here, X ₁ is the amount of dissolved gas extracted, X
₀ is the amount of dissolved gas in the insulating oil (in the oil sampling bottle), F is the flow rate of the extracted gas, t is the extraction time, K is the equilibrium constant, V ₀ is the volume of the insulating oil, and Vv is the volume of the pressure reducing section (gas storage means). Are respectively shown.

The extraction rate based on the above formula is such that the volume of the piping system for feeding and storing the dissolved gas is equal to the gas storage pipe 2 for the dissolved gas.
The smaller the storage volume of No. 4, the higher the extraction rate. This is to prevent diffusion of the extracted dissolved gas and to reliably prevent re-dissolution due to gas-liquid equilibrium. That is, it is for extracting the dissolved gas from the insulating oil 4 efficiently.

For example, the extraction time of the dissolved gas generally peaks at about 1 minute after the start of the extraction, and the extraction becomes almost stagnant (almost completed) after about 2 minutes. In the present embodiment, the extraction is performed within 3 to 5 minutes from the relationship with the storage of the dissolved gas described below, thereby improving the efficiency of extracting the dissolved gas and shortening the extraction time. The valves installed in each piping system,
Whether the operation of the cock opening / closing means and the operation of the vacuum pump are performed manually or automatically may be arbitrarily set.

The dissolved gas extracted as described above is fed through a small-diameter gas flow pipe 20, as shown in FIG.
The gas is sequentially stored in a plurality (three in this example) of gas storage pipes 24, 24, 24 provided in the gas storage means 21. In this case, since the gas circulation pipe 20 has a small diameter and has been decompressed in advance, the dissolved gas is quickly circulated and sent to the gas storage pipes 24 larger in diameter than the gas circulation pipe 20 and stored for one hour. You. Although the dissolved gas is stored in the gas storage pipe 24 as described above, one part of the dissolved gas remains in the gas distribution pipe 20 connecting the gas storage pipes 24 in the gas analysis unit 31. Needless to say.

The extraction of the dissolved gas is stopped when a predetermined extraction time set in advance has elapsed. This is performed by closing the injection valve 19 to supply the first carrier gas. When the extraction of the dissolved gas is stopped, the extracted dissolved gas is supplied to the gas flow pipe 2 through which the gas is passed.
3, since the extraction means 12 and the gas storage means 21 are connected in parallel as shown in FIG. 3, they are uniformly stored in each gas storage pipe 24 at substantially the same pressure.

The dissolved gas extracting means 12 and the gas storing means 21 are surrounded by a predetermined heat retaining means 28 and are always maintained at a temperature suitable for extraction. There is no such thing as condensing and obstructing the flow while flowing through the inside 20, and the gas can be smoothly, satisfactorily and quickly fed to the gas storage pipe 24.

Further, the types of the dissolved gas components are mainly oxygen [O ₂ ], nitrogen [N ₂ ], hydrogen [H ₂ ], carbon monoxide [CO], carbon dioxide [CO ₂ ], methane [CH ₄ ],
Ethane [C ₂ H ₆ ], ethylene [C ₂ H ₄ ], acetylene [C ₂ H ₂ ] gas, etc. are dissolved, and depending on the detected amount of these dissolved gases, transformer failure (abnormality) The purpose is to determine the degree of aging and the like.

Next, when the dissolved gas extracted by the extraction means 12 is quantitatively stored in the gas storage means 21, FIG.
In FIG. 4, the three electromagnetic switching valves 22 to 22b are closed by a command signal from a control device (not shown) so as to close the flow path that previously communicated the gas flow pipe 20 with the gas storage pipe 24.
As shown in (2), the flow path is switched to a flow path that allows the three gas flow pipes 23 and the three gas storage pipes 24 to communicate with each other. Since the second carrier gas flows through the gas analyzing means 31 at a constant pressure during the extraction of the dissolved gas through the gas flow pipes 23, 23, 23, the electromagnetic switching valves 22 to 22b are switched. With the change of the flow path by the operation, the second carrier gas supplies the dissolved gas in each gas storage pipe 24 to the gas analysis means 31 through the second gas flow pipe 23a at a constant gas pressure.

The dissolved gas in each of the gas storage pipes 24, 24, 24 sent to the gas analyzing means 31 is supplied to the gas analyzing means 3.
1, and sequentially sent to a gas separation unit (not shown) provided in
At the time of passing through the separation section, the dissolved gas is separated into single-component gases by the separation action of the gas separation section. Then, the dissolved gas separated into the single component is supplied to a flame ionization detector (hereinafter, referred to as FID) and a thermal conductivity detector (hereinafter, referred to as FID) installed in the gas analyzer 31.
(Referred to as TCD), and the corresponding types of gases are detected by the FID and TCD detectors, respectively.

The detected gas, that is, the gas detected by the FID, is generally a hydrocarbon-based C
O, CO ₂ , CH ₄ , C ₂ H ₆ , C ₂ H ₄ , C ₂ H ₂ gas, and conversely, the gas detected by TCD is inorganic H ₂ , O ₂ , N ₂ gas Is detected. And the F
In the gas detection by the ID, the gas of CO and CO ₂ is difficult to detect by the current FID, that is, it is difficult to detect the gas. Therefore, the gas detection of CO and CO ₂ is performed by attaching a metanizer to the FID. .

Each of the FID and TCD detectors for performing the gas detection is configured to output an output voltage corresponding to the gas detection time corresponding to the detected gas. Output voltages output from the FID and TCD in accordance with the gas detected by passing through the detector are sequentially sent to the data storage means 35 as detection signals, and are subjected to arithmetic processing. The data storage means 35 stores the data subjected to the arithmetic processing, and displays the data on a display or prints it on a printer as necessary. The deterioration / abnormality of the transformer 1 is determined by comparing the threshold value of the deterioration / abnormality (abnormality) set for each gas component.

In the extraction of the dissolved gas by the method shown in FIGS. 3 and 4, since the extraction means 12 and the gas storage means 21 are connected in parallel, the dissolved gas extracted from the insulating oil 4 is
Each of the three gas storage tubes 24 is stored at a uniform (uniform) concentration. Therefore, among the dissolved gases, for example, hydrogen gas [H ₂ ] is detected by the TCD as a detector. However, in the case of H ₂ , when helium gas [He] is used as a carrier gas, the thermal conductivity is close to each other, so that the gas analysis sensitivity is significantly lower than other gas components, and it is difficult to detect the H ₂ gas itself. Becomes In such a case, for example, a nitrogen gas [N
₂ ], the use of argon gas [Ar] makes it possible to easily detect H ₂ gas. In this case, if I is contained many H ₂ itself by increasing the concentration of dissolved gas, the detection of H ₂ be used He as carrier gas allows.

Next, the configuration of a gas analyzer 11a shown as a second embodiment of the present invention will be described with reference to FIG. 5 is different from the gas analyzer 11 described in the first embodiment shown in FIG. 3 only in that two electromagnetic switching valves 22 and 22a are provided. That is, the dissolved gas extraction means 12, the gas storage means 21, and the gas analysis means 3
Since the basic configuration of 1 (in this case, the number of TCDs is reduced by 1) is the same as that of the gas analyzer 11 described in the first embodiment, the description thereof is omitted. In FIG. 5, the electromagnetic switching valve 2
The outlet 2 is provided with a closing valve 28 to prevent the dissolved gas stored in the gas storage tube 24 from flowing out. In the gas analysis of the insulating oil 4, it is needless to say that the insulating oil 4 is sealed in the oil sampling bin 13 and the inside of the gas flow pipe 20 through which the dissolved gas flows is reduced in pressure by the vacuum pump 26.

In the gas analyzer 11a according to the second embodiment, the insulating oil 4
Then, the dissolved gas is extracted by ejecting the first carrier gas into the oil sampling bin 13 and stored in the gas storage pipes 24, 24 through the gas flow pipe 20 having a small diameter. In this case, the gas flow pipe 20 is connected to the oil sampling bin 13 and the gas storage pipes (electromagnetic switching valves 22, 22a) 24, 24 in parallel (individually by using two flow pipes). The gas is evenly stored in the gas storage pipes 24,24. As shown in FIG. 6, the stored dissolved gas obtains the pressure of the second carrier gas by the switching operation of the two electromagnetic switching valves 22 and 22a to obtain the second gas flow pipe 2.
The gas is supplied to the gas analyzing means 31 through 3a and 23a, and is sequentially separated into a single component gas to perform gas detection. The data of the gas detected by the gas analyzer 11a is processed by the data storage means 35 and stored.

The gas analyzer 11 in the second embodiment.
In the case of a, the gas storage pipes 24, 24 are narrowed down to two, so that the extracted concentration of the dissolved gas stored evenly is further increased with respect to the gas analyzer 11 of the first embodiment. This is because, for example, the concentration of hydrogen gas [H ₂ ] contained in the dissolved gas is increased to facilitate the detection of the H ₂ by the TCD as a detector of the gas analyzer 31.

Further, even when there is concern about the detection of H ₂ by TCD, the gas analyzer 11a of the second embodiment can reduce the amount of nitrogen gas [N ₂ ] used as a carrier gas. Thereby, in the gas analyzer 11a, the detection of H ₂ increases the concentration of the dissolved gas,
As compared with the gas analyzer 11 of the first embodiment, a single component gas can be detected from the dissolved gas with higher efficiency, and the accuracy of detecting the gas from the dissolved gas can be improved satisfactorily. In the gas analyzer 11a of the second embodiment, the gas analyzer 31 for analyzing the dissolved gas and the data storage 35 for storing the detected data of the analyzed gas are the same as those of the gas analyzer 11 described in the first embodiment. Since they are the same as the gas analyzing means 31 and the data storing means 35 used in the above, the description of the configuration and operation will be omitted.

Next, the configuration of a gas analyzer 11b shown in FIG. 7 as a third embodiment of the present invention will be described. The difference between the gas analyzer 11b of the third embodiment shown in FIG. 7 and the gas analyzer 11a of the second embodiment is that the method of storing the dissolved gas is different. That is, in the gas analyzer 11a of the second embodiment, the gas flow pipe 20
And the two gas storage tubes 24, 24 are connected in parallel so as to uniformly store the dissolved gas in the gas storage tubes 24, 24.

On the other hand, in the gas analyzer 11b of the third embodiment of the present invention, as shown in FIG. 7, the oil collecting bin 13 and the two gas storage tubes 24, 24 are connected to the gas flow tube 20 and the two electromagnetic The pipes are connected in series via the switching valves 22c and 22d. That is, in more detail in FIG.
The small-diameter gas flow pipe 20 derived from the
c, and is connected to the second gas storage tube 24 from the outlet 24a of the gas storage tube 24 via the electromagnetic switching valve 22d, and further connected to the second gas storage tube 24. Pressure gauge 25 from outlet 24b → switching cock 2
7, and is connected to a vacuum pump 26.

The gas analyzer 11b shown in the third embodiment.
As shown in FIG. 7, each gas storage pipe 24, 24 and the electromagnetic switching valve 22c,
It is characterized in that a DC pipe is connected to 22d, and the dissolved gas extraction means 12, gas storage means 21, and gas analysis means 31 (in this case, TCD is 1
) And data storage means 35,
Since it is the same as that used for the gas analyzers 11 and 11a of the second embodiment, the description is omitted.

Next, the gas analyzer 11 shown in the third embodiment will be described.
The operation of b will be described. The dissolved gas extracted from the insulating oil 4 in the oil sampling bin 13 at the gas pressure of the first carrier gas enters the gas flow pipe 20 having a small diameter. → electromagnetic switching valve 22 c → first gas storage pipe 24
→ Gas flow pipe 20 → Electromagnetic switching valve 22d → Stored in second gas storage pipe 24. In this case, it goes without saying that the pressure inside the gas flow pipe 20 is reduced by the vacuum pump 26 at a preset pressure.

As described in the first embodiment, the time for extracting the dissolved gas is about 3 to 5 minutes, but the extraction of the dissolved gas itself is almost completed within about 2 minutes. . Therefore, in the gas analyzer 11b of the third embodiment as well, the dissolved gas is extracted within about 2 minutes from the start of the extraction, but most of the extracted dissolved gas is stored in the second gas storage pipe 24. Is done. This means that the gas flow pipe 20 connects each gas storage pipe 24, 24 in series (as one flow pipe).
Because they are connected.

As a result, in FIG. 7, the concentration of the dissolved gas collected in the second gas storage tube 24 is high, while the concentration of the dissolved gas stored in the first gas storage tube 24 is low.・ It will be stored. The dissolved gas extracted by the gas analyzer 11b of the third embodiment is
1, as shown in FIG.
By the switching operation of 2c and 22d, the gas flow pipe 23 through which the second carrier gas flows and the gas storage pipe 24 are communicated, and the dissolved gas in the gas storage pipe 24 is discharged to the second gas flow pipes 23a and 23a. To the gas analyzing means 31 via

A dissolved gas having a relatively low concentration in the first gas storage tube 24 is sent to the FID of the gas analyzer 31, while the dense dissolved gas stored in the second gas storage tube 24 is sent to the TCD. Gas is sent. The dissolved gas sent to each detector is separated into a single-component gas by a separation unit (not shown), and the separated single-component gas is detected by the corresponding detectors of FID and TCD. Then, the detection data (output voltage) is sent to the data storage means 35, where the detection processing is performed and stored.

In the gas analyzer 11b of the third embodiment, as described above, the dissolved gas is sent to the gas analyzer 31 while being separated and stored in a rich / light state. Then, hydrogen gas [H ₂ ], which is hard to be detected particularly in a dilute state, can be detected well even when helium gas [He] is used as the second carrier gas. In other words, by changing the concentration of the dissolved gas as necessary, it is possible to reliably ensure the separation accuracy in the separation unit, thereby ensuring the gas detection accuracy of a single component required for detection. As a result, highly accurate gas analysis can be performed quickly and reliably. This is convenient because highly reliable reference data required for determining abnormality / deterioration of the transformer 1 can be easily obtained.

In the present invention, as described above, when the analysis of one sample (insulating oil) is completed, the discharge valve 1
6 is opened, and the insulating oil 4 in the oil sampling bin 13 is discharged to the waste oil drain 17 through the drain pipe 15 while the first carrier gas is jetted. When the discharge of the insulating oil 4 is completed, the discharge valve 16 is closed and the injection valve 19 is closed to stop the ejection of the first carrier gas. In this state, the vacuum pump 26 is driven to wash the inside of the gas flow pipe 20, the electromagnetic switching valves 22, 22a, 22b, 22c, 22d, and the gas storage pipe 24 to prepare for the next sample gas analysis.

[0067]

According to the present invention, as described above, when the dissolved gas extracted from the electric insulating oil is sent to the gas chromatograph, the gas is sent using the pressure of the carrier gas which does not adversely affect the dissolved gas. As described above, there is no need for a mechanically constructed special extraction device such as a Tepler pump system, a piston system, or a bellows system to send out the dissolved gas, as in the prior art. Simple and economical configuration is possible.

Further, in the present invention, since the dissolved gas is extracted in a uniform or non-uniform state, the qualitative / quantitative analysis of the dissolved gas by a gas chromatograph is performed. , Because it is always possible to detect a single component gas with the optimal amount (extraction rate) of dissolved gas,
It is convenient because it is possible to obtain reference data for judging failure / deterioration of the oil-filled electrical equipment with high accuracy.

Further, since the gas flow pipe through which the extracted dissolved gas flows is a pipe smaller in diameter than the gas storage pipe for temporarily storing the dissolved gas, diffusion of the dissolved gas is suppressed well. As a result, the extraction rate can be increased, so that the analysis sensitivity of the detected gas by gas chromatography can be favorably maintained and expanded. In addition, since the flow path and the storage site of the dissolved gas are always kept at a predetermined temperature, the dissolved gas can be supplied smoothly without condensing, without reducing the amount of extraction. .

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view of an oil-filled electric device.

FIG. 2 is an explanatory diagram showing a state of extracting insulating oil.

FIG. 3 is a piping configuration diagram schematically showing a means for extracting and storing dissolved gas in the gas analyzer of the present invention.

FIG. 4 is a piping configuration diagram illustrating a state in which a dissolved gas is sent to gas analysis means.

FIG. 5 is a piping configuration diagram showing a second embodiment of the gas analyzer of the present invention.

FIG. 6 is a piping configuration diagram showing a state in which a dissolved gas is sent to gas analysis means in the second embodiment.

FIG. 7 is a piping configuration diagram showing a third embodiment of the gas analyzer of the present invention.

FIG. 8 is a piping configuration diagram showing a state in which a dissolved gas is sent to gas analysis means in the third embodiment.

[Explanation of symbols]

 11, 11a, 11b Gas analyzer 12 Detecting means 13 Oil sampling bottle 18 Gas supply pipe 20 Gas circulation pipe 22, 22a, 22b, 22c, 22d Electromagnetic switching valve 24 Gas storage pipe 31 Gas analysis means 35 Data storage means

Continued on the front page (51) Int.Cl. ⁷ Identification code FI G01N 30/86 G01N 30/86 P 33/28 33/28

Claims (6)

(57) [Claims] 1. A storage container for electrically insulating oil, a gas supply pipe for supplying a first carrier gas to the storage container at a constant pressure, a gas storage pipe for storing dissolved gas extracted from the storage container, and A gas flow pipe that communicates with the storage pipe to flow the dissolved gas and a gas flow pipe that allows the second carrier gas to flow at a constant pressure; and a storage pipe and a flow pipe for the dissolved gas. An electromagnetic switching valve for arbitrarily connecting and connecting the gas flow pipe, a pressure reducing means for reducing the pressure of the storage container and the flow path of the dissolved gas, and a dissolved gas stored in the gas storage pipe by the second carrier gas. A gas analyzing means for qualitatively and quantitatively analyzing the gas, and a gas component of the dissolved gas analyzed by the gas analyzing means is arithmetically processed to store the reference data necessary for judging abnormality / deterioration of the oil-filled electric equipment in a retrievable manner. Data processing An analyzer for analyzing gas in an electrically insulating oil characterized by comprising: 2. The solenoid-operated directional control valve according to claim 1, wherein a plurality of the electromagnetic switching valves are provided in parallel with a storage container of the electrically insulating oil, with a gas flow pipe through which a second carrier gas flows. It is characterized in that it is connected via a gas flow pipe and the outflow side of the dissolved gas is individually connected to a detector of a predetermined gas incorporated in the gas analyzer via the gas flow pipe. The apparatus for analyzing gas in an electrically insulating oil according to claim 1. 3. The electric insulating oil according to claim 2, wherein the electromagnetic switching valve is arranged so as to uniformly store the dissolved gas stored in the gas storage pipe for each gas storage pipe. Medium gas analyzer. 4. The electric insulation according to claim 2, wherein the electromagnetic switching valve is arranged so as to store the dissolved gas stored in the gas storage pipes non-uniformly for each gas storage pipe. Gas-in-oil analyzer. 5. The apparatus for analyzing gas in an electrically insulating oil according to claim 2, wherein the gas flow pipe is formed by using a pipe having a smaller diameter than a gas storage pipe. 6. A flow path and a storage site of the dissolved gas,
2. The apparatus for analyzing gas in an electrically insulating oil according to claim 1, further comprising a heating means for maintaining a predetermined temperature suitable for extraction and flow of the dissolved gas.