JPH0658357U - Dissolved gas concentration analyzer in oil - Google Patents

Abstract

(57) [Summary] [Purpose] To quickly discharge the residual gas in the gas detection space, and also to discharge the residual gas and oil droplets in the gas supply channel. [Structure] First and second three directions in the middle of a gas supply passage provided between a gas storage chamber 2 for storing gas extracted by a gas extraction device 1 and a gas detection space 3 in which a gas concentration sensor is arranged. An on-off valve device including valves (SV3, SV4) is provided. In the measurement preparation stage, the atmosphere is caused to flow into the gas reservoir 2 through the second three-way valve SV4 → the pipe P4 → the first three-way valve SV3 → the pipe P2 to produce a mixed gas. At the measurement stage, from the gas storage chamber 2 to the pipe P2 → first three-way valve SV3 →
The mixed gas is supplied to the gas detection space 3 through the pipe P4 → the second three-way valve SV4 → the pipe P5. In the non-measurement stage, in addition to directly exhausting gas from the gas detection space 3 through the pipe P7,
Exhaust is performed in the flow path of the pipe P5 → the fourth three-way valve SV4 → the pipe P4 → the first three-way valve SV3 → the pipe P6 → the pipe P7.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to an in-oil dissolved gas concentration analyzer for measuring the concentration of dissolved combustible gas in insulating oil used in oil-filled equipment.

[0002]

[Prior art]

 Many techniques have been proposed in the past for extracting dissolved gas from oil and measuring the concentration of combustible gas dissolved in oil. Various methods have been proposed for measuring the concentration of combustible gas, but the gas concentration detection method by the catalytic combustion method is widely used. The catalytic combustion method utilizes, for example, the fact that air containing a combustible gas is adsorbed on the surface of a catalyst heated to an appropriate temperature and the combustible gas is catalytically combusted by the reaction with oxygen in the air. This is a concentration detection method in which the metal body is heated and the change in the electrical resistance of the metal body is measured to detect the concentration of flammable gas.

FIGS. 2A and 2B show schematic configurations of a conventional dissolved gas concentration analyzer in oil using a catalytic combustion type gas concentration sensor at a measurement preparation stage and a measurement stage. In these figures, 101 is a gas extractor for extracting combustible gas from oil with the valve 102 closed, and 103 is a gas reservoir chamber for storing the gas extracted by the gas extractor 101 through the valve 102. . A gas detection space 104 is filled with a mixed gas obtained by introducing the atmosphere into the gas storage chamber 103 via a valve 105. The gas detection space 104 contains the gas concentration of the combustible gas in the mixed gas. A catalytic combustion type gas concentration sensor for detecting is arranged. Further, 106 is a three-way valve provided in a gas supply passage provided between the gas storage chamber 103 and the gas detection space 104, and 107 is a gas forcibly supplying the atmosphere into the gas detection space 104. The air pump is a forced exhaust device that forcibly exhausts the gas in the detection space 104. At the measurement stage, as shown in FIG. 2 (B), the three-way valve 106 is opened and the mixed gas is supplied from the gas reservoir chamber 103 into the gas detection space 104 in which the gas concentration sensor is arranged to measure the concentration of the combustible gas. Set. When the measurement is finished, the three-way valve 106 is opened to open or close the gas detection space 104 to the atmosphere by using a part of the gas supply passage as an exhaust passage as shown in FIG. It was driven to discharge the residual mixed gas from the gas detection space 104.

[0004]

[Problems to be solved by the device]

 In the conventional structure, when the gas is discharged from the gas detection space 104 in the non-measurement stage, the gas is discharged from only one exhaust flow path, so when the analysis cycle becomes short, the gas is completely discharged from the gas detection space 104. However, there was a problem in that the gas could not be discharged into the room and an error occurred in the analysis value due to the residual gas. In addition, with the conventional configuration, it is not possible to eliminate the residual gas and oil droplets located in the gas supply flow path that communicates between the gas storage chamber 103 and the gas detection space 104. Therefore, residual gas and oil droplets in these gas supply channels also caused errors in the analysis values.

An object of the present invention is to provide an apparatus for analyzing dissolved gas concentration in oil, which is capable of quickly discharging residual gas in the gas detection space.

Another object of the present invention is to provide an apparatus for analyzing dissolved gas concentration in oil, which can discharge residual gas and oil droplets located in the gas supply passage.

[0007]

[Means for Solving the Problems]

 As can be seen from the embodiment shown in the drawings, the present invention comprises a dissolved gas extraction device 1 for extracting a combustible gas from oil and storing the combustible gas in a gas storage chamber 2, and a dissolved gas extraction device 1. A gas detection space 3 filled with a mixed gas obtained by introducing the atmosphere into the gas storage chamber 2, and a catalytic combustion type which is arranged in the gas detection space 3 and detects the gas concentration of the combustible gas in the mixed gas. A gas supply passage (P2, SV3, P4, SV4, which is configured to include a gas concentration sensor and an on-off valve device (SV3, SV4) and is provided between the gas storage chamber 2 and the gas detection space 3 P5), a forced exhaust device 4 for forcibly supplying the atmosphere into the gas detection space 3 to forcibly exhaust the gas in the gas detection space from the exhaust flow passage P7, and provided in the middle of the gas supply flow passage. Of the dissolved gas concentration analyzer in oil consisting of To. In the invention of claim 1, the opening / closing valve device allows the atmosphere to flow into the gas reservoir 2 through a part of the gas supply passage in the measurement preparation stage, and from the gas reservoir 2 in the measurement stage. The mixed gas is allowed to flow into the detection space 3, and the communication between the gas storage chamber 2 and the gas detection space 3 is blocked in the non-measurement stage in which the forced exhaust device 4 is activated, and the gas detection space 3 is supplied with the gas. It is designed to communicate with the atmosphere through most of the road.

According to the second aspect of the present invention, the on-off valve device is provided with the first and second three-way valves SV3 and SV4 for selectively circulating the first circulation port with the second circulation port or the third connection port. Constitute. The second flow port of the first three-way valve SV3 is connected to the gas storage chamber 2 via the first flow path P2 so that the third flow port can communicate with the atmospheric space, and the first flow port. Is connected to the first flow port of the second three-way valve SV4 via the second flow path P4. Then, the second flow port of the second three-way valve is communicated with the atmospheric space, and the third flow port is connected to the gas detection space 4 via the third flow path P 5.

According to the third aspect of the invention, the third flow port of the first three-way valve SV3 is connected to the atmospheric space via the bypass flow passage P6 and the exhaust flow passage P7.

[0010]

[Action]

 According to the first aspect of the present invention, in the non-measurement stage in which the forced exhaust device is operated, the on-off valve device blocks the communication between the gas storage chamber and the gas detection space, and the gas detection space is passed through most of the gas supply passage. In order to communicate with the atmospheric space, it is possible to provide another exhaust flow path utilizing the gas supply flow path in addition to the exhaust flow path provided for the gas detection space. When the gas in the gas detection space is exhausted from the two exhaust flow paths, the gas can be sufficiently exhausted from the gas detection space even if the analysis is performed with a shorter analysis cycle than the conventional one. Further, since the atmosphere supplied to the gas detection space by the forced exhaust means can discharge most of the gas and oil droplets remaining in the gas supply flow path at the same time, there is less error in the analysis value than before. it can.

According to the second aspect of the invention, the on-off valve device can be easily configured by using the first and second three-way valves.

When the third flow port of the first three-way valve is connected to the exhaust flow passage through the bypass flow passage as in the invention of claim 3, the gas is discharged from most of the gas supply flow passage in the non-measurement stage. The collected oil droplets can be collected all at once, which facilitates maintenance.

[0013]

【Example】

 Embodiments of the present invention will be described below with reference to the drawings. 1 (A) to 1 (C) are views for explaining the schematic configuration and operation of the dissolved gas concentration analyzer in oil of the present invention. In these drawings, reference numeral 1 denotes a dissolved gas extraction device for extracting a combustible gas from oil and storing the combustible gas in a gas storage chamber, which is composed of a gas extraction cylinder 1a and a piston 1b. The piston 1b is provided with two telescopic pipes P1 and P2, one end of which communicates with the interior of the cylinder 1a. The pipe P1 is connected to the on-off valve SV1, and the on-off valve SV2 is connected to the pipe P3 provided on the bottom wall of the cylinder 1a. FIG. 1A shows a state (non-measurement stage) before the insulating oil is supplied to the cylinder 1a. First, the on-off valves SV1 and SV2 are opened, and insulating oil is supplied and circulated from the oil-filled electric device (not shown) into the cylinder 1a by a pump (not shown). Next, after closing the on-off valves SV1 and SV2, the on-off valve SV1 is opened again, the piston 1b is pulled up to a predetermined height, and a predetermined amount of insulating oil is supplied into the cylinder 1a. At this time, the three-way valves SV3 and SV4 are in the closed state shown in the drawing with respect to the pipe P2. The three-way valves SV3 and SV4 have a configuration in which the first circulation port is selectively communicated with the second circulation port or the third connection port.

After injecting the insulating oil into the cylinder 1a, the on-off valves SV1 and SV2 are closed, the piston 1b is pulled up to bring the inside of the cylinder 1a into a negative pressure state, and the dissolved gas is extracted from the insulating oil. At this time, a gas space is formed in the cylinder 1a, and this gas space constitutes the gas storage chamber 2. Thereafter, as shown in FIG. 1B, a three-way valve SV3 having a second flow port connected to the pipe P2 and a first flow port connected to the first flow port of the three-way valve SV3 via a pipe P4. The opened three-way valve SV4 is opened as shown. At this time, the second circulation port of the three-way valve SV4 communicates the pipe P4 with the atmospheric space, and the atmosphere is supplied to the inside of the cylinder 1a through the pipes P2 and P4 communicated with the three-way valve SV3. As a result, the gas storage chamber 2 formed in the cylinder 1a is filled with a mixed gas of a dissolved gas and the atmosphere. The state of FIG. 1B is the state of the measurement preparation stage.

After the gas storage chamber 2 is filled with the mixed gas, the on-off valves SV1 and SV2 are kept closed so that the pipe P4 and the pipe P5 communicate with each other as shown in the measurement stage diagram of FIG. 1 (C). , The three-way valve SV4 is closed (the first circulation port and the third circulation port of the three-way valve SV4 are connected), the piston 1b is lowered, and the gas detection space 3 in which the catalytic combustion type gas concentration sensor is stored The mixed gas is supplied from the gas storage chamber 2 to the.

A pipe P7 forming an exhaust flow path is connected to the gas detection space 3, and the mixed gas is gradually exhausted from the pipe P7. An air pump 4 that constitutes a forced exhaust device is connected to the gas detection space 3, and the air pump 4 is driven after the analysis of the gas concentration is completed to forcibly mix the mixed gas from the gas detection space 3. Discharge.

The concentration of the mixed gas supplied to the gas detection space 3 is measured by a well-known catalytic combustion type gas concentration sensor. When the measurement is completed, the three-way valve SV3 is closed so as to connect the pipe P4 and the pipe P6 as shown in FIG. 1 (A) (the first and third flow ports of the three-way valve SV3 are connected to each other). Then, the on-off valve SV2 is opened and the piston 1b is further pushed down. As a result, the insulating oil is discharged from the cylinder 1a. The piston 1b is not lowered to the lowermost portion, but a predetermined amount of insulating oil is left in the cylinder 1a. When the discharging of the insulating oil is completed, the open / close valve SV2 is closed.

After the insulating oil is discharged from the cylinder 1 a or in parallel with this, the air pump 4 is driven to discharge the gas from the gas detection space 3. At this time, the three-way valves SV3 and SV4 are in the state shown in FIG. 1 (A), and the atmosphere forcedly supplied from the air pump 4 to the gas detection space 3 is the first exhaust gas composed of the pipe P7. Flow through the flow path and the second exhaust flow path composed of the pipe P5, the pipe P4, the pipe P6 and the pipe P7 which are in communication with each other by the three-way valves SV3 and SV4, and from the gas detection space 3 through these two flow passages. The gas is discharged quickly. At this time, the gas and oil droplets remaining in the pipes P5 and P4 forming a part of the flow path for supplying the gas to the gas detection space 3 are simultaneously discharged through the second exhaust flow path. Therefore, according to the present embodiment, not only the gas detection space 3 but also the gas and oil droplets remaining inside the pipes P5 and P4 can be discharged at the same time, so that even if the analysis cycle becomes short, detection by residual gas or oil droplets is possible. The decrease in accuracy can be greatly suppressed. In order to eliminate residual gas and oil drops as much as possible, it is preferable that the three-way valve SV3 be installed as close as possible to the outlet of the gas storage chamber of the dissolved gas extraction device.

In this embodiment, the pipe P2, the pipe P4, the pipe P5, and the three-way valves SV3 and SV4 form a gas supply passage. The pipe P2 constitutes the first flow passage and the pipe P4 constitutes the second flow passage for the three-way valve SV3. Further, the pipe P5 constitutes a third flow path for the three-way valve SV4.

In this embodiment, since the pipe P6 is connected to the pipe 7, there is an advantage that the discharged oil droplets can be easily treated. Needless to say, the pipe P6 may not be connected to the pipe 7.

In the present embodiment, the cylinder type extraction device is used as the dissolved gas extraction device, but it goes without saying that the present invention can be applied to the case of using other dissolved gas extraction devices.

[0022]

[Effect of device]

 According to the invention of claim 1, since the gas in the gas detection space is exhausted from the two exhaust flow paths, the gas can be sufficiently exhausted from the gas detection space even if the analysis is performed at a shorter analysis cycle than the conventional one. You can Further, since the atmosphere supplied to the gas detection space by the forced exhaust means can simultaneously discharge most of the gas and oil droplets remaining in the gas supply flow path, it is possible to reduce the error in the analysis value compared to the conventional method. There is.

According to the invention of claim 2, there is an advantage that the on-off valve device can be easily configured by using the first and second three-way valves.

According to the third aspect of the present invention, since the third flow port of the first three-way valve is connected to the exhaust flow channel via the bypass flow channel, most of the gas supply flow channel is not measured at the non-measurement stage. The discharged oil droplets can be collected all at once, which has the advantage of facilitating maintenance.

[Brief description of drawings]

1A to 1C are views for explaining a schematic configuration and operation of an apparatus for analyzing dissolved gas concentration in oil according to an embodiment of the present invention.

2A and 2B are diagrams for explaining a schematic configuration and operation of a conventional analyzer for dissolved gas concentration in oil.

[Explanation of symbols]

 1 Dissolved gas extraction device 2 Gas storage chamber 3 Gas detection space 4 Air pump (forced exhaust device) SV1 open / close valve SV2 open / close valve SV3 three-way valve (first three-way valve) SV4 three-way valve (second three-way valve) P1 to P7 piping

Front page continuation (72) Hitoshi Nakamura 1-8-24, Chuo-cho, Meguro-ku, Tokyo Komei Rikagaku Co., Ltd. (72) Hideyasu Tanno 1-8-24 Chuo-cho, Meguro-ku, Tokyo Komei Within RIKA CORPORATION

Claims (3)

[Scope of utility model registration request] 1. A dissolved gas extraction device for extracting a combustible gas from oil to store the combustible gas in a gas storage chamber; and a mixed gas obtained by introducing air into the gas storage chamber of the dissolved gas extraction device. A gas detection space to be filled, a contact combustion type gas concentration sensor arranged in the gas detection space to detect the gas concentration of the combustible gas in the mixed gas, and an open / close valve device. A gas supply flow passage provided between the gas storage chamber and the gas detection space, and forcibly supplying the atmosphere into the gas detection space to force the gas in the gas detection space from the exhaust flow passage. An apparatus for analyzing dissolved gas concentration in oil comprising a forced exhaust device for exhausting, wherein the on-off valve device, in the measurement preparation stage, the atmosphere flows into the gas reservoir through a part of the gas supply channel. Is allowed during the measurement stage. The mixed gas is allowed to flow from the reservoir to the gas detection space, and the gas is prevented from communicating with the gas detection space in the non-measurement stage of operating the forced exhaust device. An apparatus for analyzing a dissolved gas concentration in oil, wherein the detection space is configured to communicate with the atmospheric space through most of the gas supply flow path. 2. The on-off valve device is constituted by first and second three-way valves which selectively circulate the first flow port with the second flow port or the third connection port, and the first three-way valve. The second flow port of the valve is connected to the gas reservoir through the first flow path, the third flow port is in communication with the atmospheric space, and the first flow port is through the second flow path. The second
Connected to the first flow port of the three-way valve, the second flow port of the second three-way valve communicates with the atmospheric space, and the third flow port of the third three-way valve through the third flow path to the gas detection space. The dissolved gas concentration analyzer in oil according to claim 1, which is connected to the. 3. The dissolved gas concentration in oil according to claim 2, wherein the third flow port of the first three-way valve is connected to the exhaust flow passage through a bypass flow passage and communicates with the atmospheric space. Analysis equipment.