JPH0213267B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a gas analyzer, and is particularly suitable for analyzing gas dissolved in insulating oil of oil-filled electrical equipment such as transformers.

An extremely effective method is to analyze gas dissolved in insulating oil collected from operating transformers and other oil-filled electrical equipment, and diagnose internal abnormalities in oil-filled electrical equipment based on the composition and concentration of its constituent components. Currently widely used.

The gas dissolved in insulating oil has nitrogen and oxygen as its main components, but in addition to this, it is also caused by thermal decomposition of insulating materials such as insulating oil and insulating paper in oil-filled electrical equipment due to aging and internal abnormalities. , hydrogen, carbon monoxide, carbon dioxide, methane and other hydrocarbons. Therefore, in order to detect internal abnormalities in oil-filled electrical equipment during operation, it is essential to first accurately extract the gas dissolved in the oil.

For this purpose, an oil-dissolved gas extractor as shown in FIG. 1 and a gas chromatograph for analyzing the oil-dissolved gas extracted by the apparatus are generally used. Extraction of gas dissolved in oil using this device is performed as follows.

First, close Kotoku 1, 7, and 8, then close Kotoku 2~
6 and 17 are opened, and the system consisting of the gas extraction flask 15, mercury diffusion pump 9 Teppler pump 10, and gas collector 11 is evacuated using the vacuum pump 19 connected to the pot 17, and then the pots 3 and 4 are closed. . The sample oil is measured using the sample oil measuring tube 14, and the pot 1 is opened to introduce a certain amount of the sample oil into the gas extraction flask 15. Turn the rotor 16 to stir the sample oil,
Dissolved gas is released into the space above the sample oil. The released dissolved gas passes through a mercury diffusion pump 9 and a Teppler pump 10 and is collected in a gas collector 11.

When the dissolved gas in the sample oil disappears, the vacuum gauge 13
When the specified vacuum level is reached, gas extraction is stopped,
After the gas collectors 5 and 6 are closed to collect gas in the gas collector 11, the amount of gas in the gas collector 11 is measured by moving the mercury container 12 up and down.

To analyze the dissolved gas in the extracted oil, open the tank 8, evacuate the system between the tanks 7 and 8, and the gas sampling pipe 18, close the tank 8, open the tanks 6 and 7, and collect the gas. The extracted gas in the container 11 is introduced into the gas sampling tube 18 and collected, and the gas sampling tube 18 is attached to a gas chromatograph having a separation column suitable for analyzing the constituent components of the extracted gas, and the extracted dissolved gas is collected. This is done by introducing the gas into a gas chromatograph, thereby determining the composition and concentration of the constituent components of the gas dissolved in the oil.

However, in this method, the apparatus for extracting dissolved gas in oil requires a vacuum pump or other vacuum equipment due to its configuration, and thus the apparatus becomes large-scale. Also,
Since mercury is used in mercury diffusion pumps, Teppler pumps, gas collectors, etc., which require skill and a great deal of effort to operate, care must be taken in terms of occupational safety and health.

The present invention has been made to eliminate such drawbacks, and is an apparatus particularly suitable for analyzing dissolved gases in oil, which is equipped with a sample measuring section, a gas extraction section in the sample, and a gas chromatograph. Accordingly, a carbon monoxide and carbon dioxide reduction device is attached, and a sample measuring section and a sample gas extraction section are installed in the carrier gas flow path that sends it to the gas chromatograph, and by continuously bubbling the carrier gas into the sample oil, it is possible to reduce the amount of carbon monoxide and carbon dioxide dissolved in the oil. While extracting gas, the extracted gas from the extraction section is guided to a gas chromatograph using a bubbled carrier gas to analyze the constituent components of the gas, and the analysis results are recorded. That is, extraction and analysis of gas in a sample can be performed in direct conjunction.

By using the device of the present invention, there is no need for a series of manual operations such as extracting and collecting mercury, large-scale vacuum equipment, and gases in the sample, then collecting the extracted gas and introducing it into a gas chromatograph for analysis. Therefore, the analyzer can be simplified, downsized, and labor-saving. In addition, other methods require a sample of 200 ml or more to extract and analyze the gas in the sample, but with the device of the present invention, analysis can be performed with an extremely small sample of several ml or less. Since extraction and analysis can be performed in tandem, analysis time can be significantly shortened.

An embodiment of the present invention will be described with reference to FIG. 2 regarding analysis of gas dissolved in oil in oil-filled electrical equipment.

Reference numeral 26 denotes a sample collection container, which is used as a storage container for insulating oil collected from oil-filled electrical equipment, and the sample oil contained therein is provided for analysis of gas dissolved in the oil. Reference numeral 21 denotes a sample oil measuring section, which guides the sample oil in the sample collection container 26 to a measuring tube 32 for sampling. Reference numeral 22 denotes a dissolved gas extraction section in oil, which extracts the dissolved gas in the sample measured by the measuring tube 32.

A carrier gas cylinder 23 supplies carrier gas used for extraction of gas dissolved in oil, cleaning of sample oil measuring section 21, dissolved gas extraction section 22, and the like. Nitrogen, helium, argon, hydrogen, etc. are used as the carrier gas. 24 is a gas sample container that supplies a gas sample and a reference gas. Reference numeral 25 denotes a gas chromatograph, which analyzes the gas extracted by the dissolved gas in oil extraction section 22, and is connected to the dissolved gas in oil extraction section 22 and the sample oil sampling and measuring section 21 through a carrier gas flow path. Reference numeral 27 denotes a measuring unit switching knob, which performs switching for collecting a sample oil or gas sample into the measuring tube 32 and introducing the sample oil, etc. in the measuring tube 32 into the gas-in-oil extraction container 30.

Reference numeral 28 denotes an extraction section switching switch A for switching the carrier gas from the gas chromatograph 25.
Reference numeral 29 denotes an extraction section switching cock B, which is used for discharging sample oil from the dissolved gas extraction container 30 and oil trap 31 and for cleaning the inside of the system. 30 is a dissolved gas extraction vessel in oil, which has a carrier gas injection hole with an inner diameter of 1 mm or less at the bottom. Used to extract gases dissolved in oil. The internal volume is several ml or less, and the internal volume can be changed depending on the measuring tube 32. No. 32 is a measuring tube with an internal volume of several ml or less, but the internal volume can be changed depending on the sample oil.

33 is a pressure regulating column, and the dissolved gas in oil extraction container 3
When the carrier gas is passed through the extraction section switching cock B29 into the system containing 0, the inside of the system is kept in a pressurized state. 36 is a reduction device when using a hydrogen flame ion type detector, which reduces carbon monoxide and carbon dioxide among the components separated by the separation column 51. Hydrogen is introduced just before the reduction device and mixed with the carrier gas. do.

51 is maintained at a constant temperature in a separation column, for example, molecular sieves are used for components such as nitrogen, oxygen, and hydrogen, and activated carbon and activated alumina are appropriately selected for carbon monoxide, carbon dioxide, methane, and other hydrocarbons. It can be used as 52
A detector is used to detect the components separated by the separation column 51, and is a thermal conductivity type detector or a hydrogen flame ion type detector. 31 is an oil trap, 34,
35 is a pressure reducing valve, 41 to 49 are valves, and 53 is a drain oil tank.

Next, the operation of the device configured as described above will be explained.

First, the valves 41 to 49 are closed, and the extraction section switching sockets A28 and B29 and the measuring section switching socket 27 are set to the flow paths shown by solid lines. The carrier gas passes from the cylinder 23 through the pressure reducing valve 34, and from the gas chromatograph 25 on the other hand returns to the gas chromatograph 25 via the extraction section switching switch A28.
29, is discharged to the outside via a pressure regulating column 33.

When the extraction section switching socket B29 is switched in the direction of the dotted line, the carrier gas passes through the solid line of the extraction section switching socket A28, passes through the measuring section switching socket 27, the dissolved gas in oil extraction container 30, the oil trap 31, and then returns to the extraction section switching socket A28. Street, extraction part switching trick B
29 and is discharged to the outside via a pressure regulating column 33, and the dissolved gas in oil extraction container 30 and the inside of the system are washed.
After a certain period of time has elapsed, switch the extraction section switching knob B29 again to the direction of the solid line, and at the same time switch the extraction section switching knob A.
Switch 28 in the direction of the dotted line and turn on the gas chromatograph 2.
Switch the carrier gas from 5 to the measuring section 2
7. Dissolved gas in oil extraction container 30, oil trap 31
The sample is introduced into the gas chromatograph 25 through the extraction section switching unit A28, and left as it is for a certain period of time.

During this time, sample collection container 26 is installed between valve 44 and valve 45, and then valve 49, and then valves 44, 45, 4.
When 1 is opened, the carrier gas flows into the sample collection container 26.
The sample oil is pushed up from the bottom of the sample collection container 26 by applying pressure to the upper oil level in the sample collection container 26, passes through the valve 45, and fills the measuring tube 32 with sample oil from the solid line of the measuring section switching cock 27. When the oil reaches the metering pipe 3, close the valves 41 and 44 and then the valves 45 and 49.
Collect sample oil within 2 hours.

Switch the measuring section switching knob 27 in the direction of the dotted line,
Gas chromatograph 25 to extraction section switching switch A
The sample oil collected in the metering tube is forced to be introduced into the dissolved gas extraction vessel 30 using the carrier gas passed through 28. The introduced sample oil was bubbled with a carrier gas passed from the gas chromatograph 25 through the metering tube 32 through the carrier gas outlet at the bottom of the gas dissolved in oil extraction container 30, thereby simultaneously extracting the dissolved gas in the sample oil. Gas is immediately removed from the oil trap 31 and the measuring section switching cock A2.
8 and then led to a gas chromatograph. Analysis is started at the same time as the extracted gas is introduced into the gas chromatograph 25, and the components of the gas dissolved in the oil are analyzed and recorded. The recording method is to take it out as a signal, draw a chromatogram on a recorder, and input it into a chromatographic processing device using an integrating circuit such as an integrator or a computer, and the composition and concentration of the constituent components are printed out.

The oil trap 31 is a dissolved gas extraction container 30 in oil.
This prevents some of the sample oil bubbled inside from rising up the wall of the extraction container and entering the gas chromatograph system through the pipe.

When the analysis of the dissolved gas in the sample oil is completed after a certain period of time has elapsed, switch the extraction section switching knob A28 and the measuring section switching knob 27 in the direction of the solid line to stop bubbling, and remove the dissolved gas in oil extraction container 30 and the oil trap 31.
The inside of the system, including the gas, is isolated from the outside to make it a closed system, and the system is kept pressurized by carrier gas.

When the valve 47 is opened in this state, the sample oil in the dissolved gas in oil extraction container 30 is transferred to the dissolved gas in oil extraction container 30.
When the pressurized state in the system containing 0 is released to atmospheric pressure, it is simultaneously discharged to the outside. Close the valve 47, switch the extraction part switching cock B29 in the direction of the dotted line, and adjust the pressure from the carrier gas extraction part switching cock A28, the measuring part switching cock 27, the dissolved gas in oil extraction container 30, the oil trap 31, and the extraction part switching cock B29. After flowing into the column 33 for a certain period of time and pressurizing the inside of the system, the extraction section switching cock B29 is switched in the direction of the solid line to isolate the inside of the system including the oil trap 31 from the outside. valve 48
The sample oil accumulated in the oil trap 31 is discharged at the same time as the system is released from the pressurized state.

Switch the discharge section switching switch B29 again in the direction of the dotted line to open the dissolved gas extraction container 30 and the oil trap 31.
A carrier gas is introduced into the system containing the gas, and the inside of the system is cleaned with the carrier gas.

While the inside of the system including the dissolved gas extraction container 30 is being cleaned, the valves 49, 42, and 46 are opened, and the carrier gas is guided from the solid line of the metering section switching cock 27 to the metering pipe 32, and then via the valve 46 to the outside. After cleaning the inside of the metering tube 32 while flowing with water, the valves 49, 42, and 46 are closed. This completes the analysis of the sample oil.

The above-mentioned operations are controlled by a sequence program so that the analysis of gas dissolved in oil can be performed automatically.

Further, by setting a large number of sample collection containers 26 shown in FIG. 2 and repeatedly executing the sequence program, it is possible to automatically complete the analysis of the set sample oil.

Although the analysis of dissolved gas in insulating oil collected from oil-filled electrical equipment has been described above, the device of the present invention can obtain similar effects not only in the analysis of dissolved gas in other liquids, but also in insulating oil. By using the gas sample container 24, it is possible to analyze a gas sample and calibrate the apparatus using a reference gas. Furthermore, by using gas chromatograph separation columns and detectors that correspond to the dissolved gas in the liquid and the constituent components of the gas sample, it can be applied to a wider range of applications.

[Brief explanation of drawings]

FIG. 1 is a schematic diagram of a conventionally used dissolved gas extraction device in oil, and FIG. 2 is a configuration diagram based on an embodiment of the present invention. 1-8, 17: Kotoku, 9: Mercury diffusion pump,
10: Teppler pump, 11: Gas collector, 1
2: Mercury container, 13: Vacuum gauge, 14: Sample oil measuring tube, 15: Gas extraction flask, 16: Rotor, 1
8: Gas sampling tube, 19: Vacuum pump, 21: Sample oil sampling and measuring section, 22: Dissolved gas in oil extraction section, 23:
Carrier gas cylinder, 24: Gas sample container, 2
5: Gas chromatograph, 26: Sample collection container,
27: Measuring section switching pot, 28: Extraction section switching pot A, 29: Extraction section switching pot B, 30: Dissolved gas in oil extraction container, 31: Oil trap, 32: Metering tube, 33: Pressure adjustment column, 34: Pressure reducing valve, 35: Pressure reducing valve, 36: Reduction device, 41 to 49: Valve, 51:
Separation column, 52: detector, 53: drain oil tank.

Claims (1)

[Scope of Claims] 1. A gas chromatograph comprising a sample measuring section, a sample gas extraction section, and a gas chromatograph, wherein the sample measuring section and the sample gas extraction section are arranged in a carrier gas flow path of a gas chromatograph equipped with a switching point in each section. The sample measuring section is equipped with a sample collection container and a measuring tube for collecting and measuring the sample using a carrier gas, and is equipped with a switching point that allows communication between these and the sample gas extraction section at any time. The medium gas extraction section is equipped with a dissolved gas extraction vessel in oil for extracting dissolved gas by bubbling carrier gas, and is equipped with a switching device that allows communication between this dissolved gas extraction vessel in oil, the sample measuring section, and the gas chromatograph at any time. A gas analyzer characterized by: 2. The gas analyzer according to claim 1, wherein the reference gas flow path is directly connected to the sample measuring section. 3. The gas analyzer according to claim 1 or 2, wherein the detector in the gas chromatograph is at least one of a thermal conduction type detector and a hydrogen flame ion type detector. 4 Using a hydrogen flame ion type detector as a detector,
The gas analyzer according to claim 3, further comprising a carbon monoxide and carbon dioxide reducing device.