Detection device and detection method for dissolved gas in insulating oil

Abstract

The invention discloses a detection device and a detection method for dissolved gas in insulating oil. The detection device comprises a rapid degassing module and an analysis module, the rapid degassing module comprises a sample bottle, a heating oil sample pool, a stirring structure, a high-purity gas storage tank and a cold trap; the sample bottle is used for injecting an insulating oil sample to be detected; the heating oil sample pool is used for heating the insulating oil sample in the sample bottle; the stirring structure is used for stirring the insulating oil sample in the sample bottle; the high-purity gas storage tank is used for introducing inert gas into the sample bottle and accelerating discharge of dissolved gas; the cold trap is used for enriching the mixed gas discharged from the sample bottle and selectively adsorbing and enriching the target gas to be detected; and the analysis module is used for detecting the gas analyzed from the cold trap. According to the detection device disclosed by the invention, the insulating oil sample to be detected is simultaneously subjected to heating stirring, gas purging replacement and cold trap enrichment, so that the dissolved gas in the insulating oil can be quickly removed, the degassing time is shortened to be within 5min, and the degassing treatment efficiency is greatly improved.

Description

Technical Field

[0001] The present invention relates to the technical field of component analysis, and in particular to a detection device and a detection method for dissolved gas in insulating oil. Background Art

[0002] Insulating oil is a critical insulating medium for power equipment (such as transformers, reactors, and bushings). The content and changing trends of dissolved gas components (such as H2, CH4, C2H2, CO, and CO2) within it are key indicators for assessing equipment operating status and diagnosing faults. Currently, the "GB / T 17623-2017 Gas Chromatographic Determination of Dissolved Gas Components in Insulating Oil" method is widely used both domestically and internationally. This method uses heating and shaking degassing combined with gas chromatography (GC) analysis to quantitatively detect dissolved gases. However, existing technologies have the following significant drawbacks: (1) Low pre-treatment efficiency: The traditional heating and shaking degassing method requires long-term constant temperature shaking (usually ≥30 minutes / sample), and the degassing efficiency is affected by factors such as oil sample viscosity and temperature uniformity, resulting in low batch processing throughput and difficulty in meeting the timeliness requirements of large-scale status monitoring of power equipment.

[0003] (2) Insufficient qualitative and quantitative accuracy: Gas chromatography relies on retention time for qualitative analysis, but the chromatographic peaks of complex components in insulating oil (such as C2H4 and C2H6) are prone to overlap, and it is necessary to rely on multi-column switching or retention index to assist qualitative analysis. The operation is cumbersome and prone to introduce errors.

[0004] (3) Low system integration: In the existing technology, the degassing device and the detection equipment are independent of each other. The sample transfer process may introduce air contamination or gas loss, which poses a threat to the detection reliability of trace fault characteristic gases.

[0005] In view of this, this application is hereby filed. Summary of the Invention

[0006] The problems existing in the prior art are that the pre-treatment degassing time of the existing detection method is long and the efficiency is low, and the detection system process of sample transfer may introduce air pollution or gas loss. In order to solve the above problems, the present invention provides a detection device and detection method for dissolved gas in insulating oil. Through the synergistic effect of three methods: stirring and heating, gas purging and replacement combined with cold trap enrichment, the dissolved gas in the insulating oil can be quickly removed, and the degassing time is shortened to within 5 minutes, which greatly improves the degassing processing efficiency.

[0007] The present invention is achieved through the following technical solutions: In a first aspect, the present invention provides a device for detecting dissolved gas in insulating oil, comprising a rapid degassing module and an analysis module; The rapid degassing module includes a sample bottle, a heated oil sample pool, a stirring structure, a high-purity gas storage tank, and a cold trap. The sample bottle is used to inject the insulating oil sample to be tested; The heating oil sample pool is used to heat the insulating oil sample in the sample bottle; The stirring structure is used to stir the insulating oil sample in the sample bottle; The high-purity gas storage tank is used to pass inert gas into the sample bottle to accelerate the discharge of dissolved gas in the insulating oil sample; The cold trap is used to enrich the mixed gas discharged from the sample bottle, selectively adsorb and enrich the target gas to be detected; The analysis module is used to detect the gas analyzed from the cold trap.

[0008] The detection device of the present invention can achieve rapid removal of dissolved gas in insulating oil by simultaneously heating and stirring, gas purging and replacing, and cold trap enrichment of the insulating oil sample to be tested. The degassing time is shortened to within 5 minutes, greatly improving the degassing processing efficiency.

[0009] The present invention adds a method of blowing inert gas into the oil sample on the basis of degassing by a traditional heating and shaking device. Since the solubility of inert gas in insulating oil is extremely low, microbubbles of 0.1-0.3 mm will be generated in the oil sample. The microbubbles have a large gas-liquid contact area. As the microbubbles rise in the oil sample, the dissolved gas will diffuse from the oil phase to the surface of the microbubbles, and then transfer at the gas-liquid interface. At the same time, the rising microbubbles will generate eddies in the oil sample, destroying the oil film resistance layer, so that the dissolved gas enters the microbubbles from the oil phase and is finally discharged as the bubbles move upward. Through continuous replacement, the oil sample can be quickly degassed. In addition, the continuous blowing of the inert gas will also reduce the partial pressure of the target gas in the gas phase, causing it to gradually approach zero, further promoting the removal of dissolved gas.

[0010] Conventional heating oscillations are usually performed at a frequency of 2-5 times / minute in a static thermodynamic equilibrium state, while the present application uses a dynamic thermodynamic non-equilibrium state to continuously introduce gas for displacement to form a partial pressure difference. At the same time, the bubbles will continue to burst in the oil phase to form micro-vibrations of 120-150 times / minute, thereby increasing the degassing rate.

[0011] In a specific embodiment, the components of the rapid degassing module and the analysis modules are connected by transmission lines, the transmission lines are made of inert metal, and the temperature inside the transmission lines is maintained at 100-200°C.

[0012] The present invention integrates the entire device into a closed structure through the transmission pipeline, which can avoid gas transmission losses and achieve integrated degassing detection. Furthermore, the transmission line uses an inert metal tube and is heated at 100-200°C throughout the process, which can reduce the adsorption effect of dissolved gas on the metal tube and further avoid gas transmission losses.

[0013] In one embodiment, the analysis module utilizes a gas chromatography-mass spectrometer (GC-MS). This method enables precise qualitative analysis using characteristic mass spectrometry ion fragments (e.g., m / z 26 corresponds to C2H2). Combined with the GS-GASPRO chromatographic column system, this method resolves the peak overlap problem associated with traditional GC methods, reducing quantitative repeatability (RSD) to less than 5%.

[0014] In a specific embodiment, a water trap is further provided between the sample bottle and the cold trap, and the water trap is used to capture moisture in the mixed gas discharged from the sample bottle.

[0015] In a specific embodiment, the inert gas is nitrogen or helium with a purity of ≥99.999%, and the technical indicators are as follows: oxygen <0.5ppm, water <1ppm, and gaseous hydrocarbons <0.1ppm, so as to avoid oxidation reactions in the transmission line.

[0016] In a specific embodiment, a mass flow meter is further provided between the high-purity gas storage tank and the sample bottle.

[0017] In a specific embodiment, a porous filler is provided in the cold trap, wherein the porous filler is made of carbon molecular sieve material with a maximum of 400m 2 / g specific surface area, and a pore size gradient distribution of 60-80nm, which greatly improves the gas adsorption capacity compared with traditional glass microsphere fillers.

[0018] In a specific embodiment, a silicon-based molecular sieve membrane is provided inside the transmission line, which can achieve selective water permeability and solve the problem of water interference in analysis.

[0019] In a specific embodiment, a 40 kHz high-frequency ultrasonic field is applied to the heated oil sample pool, thereby increasing the desorption rate of C2H2 in the insulating oil.

[0020] In a second aspect, the present invention further provides a method for detecting dissolved gas in insulating oil, comprising the following steps: (1) Pour an appropriate amount of the oil sample to be tested into the sample bottle, then place it into the heated oil sample pool for heating and start the stirring device; (2) Continuously introduce high-purity inert gas into the sample bottle for 30-300 seconds; (3) The displaced mixed gas is first passed into a water removal trap to remove water from the gas, and then passed into a -30°C cold trap for adsorption enrichment of the target gas; (4) The enrichment cold trap is heated to achieve decomposition of the mixed gas, and then transmitted to a gas chromatography-mass spectrometer for analysis and detection.

[0021] In a specific embodiment, the heating temperature in step (1) is 50-100°C.

[0022] In a specific embodiment, the flow rate of the inert gas introduced into the sample bottle in step (2) is 20-300 ml / min.

[0023] In a specific embodiment, the heating temperature of the water removal trap in step (3) is 60-250°C; the heating temperature of the enrichment cold trap in step (4) is 60-300°C. The specific operating method of the present invention is as follows: (1) Preheating: First, heat the transmission line of the entire device to 120°C, precool the trap to -30°C, and preheat the water trap to 180°C; (2) Preparation of the gas path in the transmission line: First, perform a gas leak test, then use a trap to enrich the inert carrier gas to increase its purity to ≥99.999%, and set a mass flow meter to accurately adjust the flow rate to 20-300 ml / min; (3) Oil sample loading stage: inject the oil sample to be tested (10-30 ml) into the constant temperature oil sample pool; heat the oil sample pool to the set temperature (50-100 °C), start magnetic stirring, and establish oil sample micro-turbulence; (4) Dynamic replacement stage: (1) Open the carrier gas passage, and inert gas is introduced into the oil sample to form microbubbles. The gas flows out with the carrier inert gas. The replacement time is 30-300s. The dissolved gas in the insulating oil is desorbed by the inert gas through heating and dynamic purging. (5) Gas capture stage: The displaced mixed gas is captured by the water removal trap at the front end of the cold trap and enters the -30℃ cold trap. From the start of the timing to the end of the enrichment, the entire time takes 180 seconds, which is the gas removal and replacement time; (6) Desorption and sampling: After gas removal is completed, the desorption and sampling are ready, the timing is started, the enrichment cold trap is quickly heated to 240 °C, and the desorbed gas is purged into the GC-MS for detection by inert gas, which takes 300 s. (7) Pipeline purification: Finally, the transmission line is purged with new high-purity inert gas; the system is ready for the next replacement cycle.

[0024] Traditional methods (such as GB / T 17623) use a single constant temperature (usually 50°C) oscillation degassing, with a degassing time of 32±5 minutes and an equipment energy consumption of 2.4kWh. The rapid degassing module of the present invention adopts a gradient temperature control method as a whole, specifically: the transmission line: 100-200°C (maintaining the gas state), the heating pool: 50-100°C (80°C optimal), the cold trap temperature: -30°C (adsorption stage) / 240°C (desorption stage), and then combined with high-purity inert gas purging, it can synergistically increase the degassing kinetic efficiency by 3 times, the degassing time is 4.2±0.3 minutes, the equipment energy consumption is 0.8kWh, and together with the GC-MS analysis detection time, the overall single sample detection time only takes 15 minutes to complete.

[0025] The specific parameters of the GCMS device for analysis and detection are as follows: injection port: 150°C; split ratio: 1, column flow rate 1.6 ml / min; program temperature: 40°C (2 min) 5°C / min 60°C 20°C / min 120°C (4 min); ion source temperature: 200°C, transfer line temperature: 200°C, scanning mode, full scan: 10-70 amu.

[0026] Compared with the prior art, the present invention has the following advantages and beneficial effects: 1. The present invention provides a device and method for detecting dissolved gas in insulating oil. The device and method can complete sample degassing within 5 minutes and single sample detection within 15 minutes, increasing degassing efficiency by 3 times and being suitable for rapid screening of large batches of samples. 2. The present invention provides a device and method for detecting dissolved gas in insulating oil. By simultaneously heating and stirring the insulating oil sample to be tested, purging and replacing it with gas, and enriching it in a cold trap, the device and method can rapidly remove dissolved gas from the insulating oil. The degassing time is shortened to less than 5 minutes, greatly improving the degassing efficiency. 3. Embodiments of the present invention provide a device and method for detecting dissolved gas in insulating oil. The GC-MS system uses mass spectrometry characteristic ion fragments (e.g., m / z 26 corresponds to C2H2) for precise qualitative analysis. Combined with the GS-GASPRO chromatographic column system, this system solves the problem of chromatographic peak overlap in traditional GC methods, reducing quantitative repeatability (RSD) to less than 5%. Combined with high-sensitivity MS detection, the detection limit for C2H2 reaches 0.1 μL / L (1 / 10 of the GB / T 17623 standard), making it suitable for early fault warning. 4. An embodiment of the present invention provides a detection device and method for dissolved gas in insulating oil. The entire device is integrated into a closed structure through a transmission pipeline, which can avoid gas transmission losses and realize integrated degassing detection. At the same time, the transmission line adopts an inert metal tube and is heated at 100-200°C throughout the entire process, which can reduce the adsorption effect of dissolved gas in the metal tube and further avoid gas transmission losses. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following is a brief introduction to the drawings required for use in the embodiments. It should be understood that the following drawings only illustrate certain embodiments of the present invention and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other relevant drawings can be obtained based on these drawings without paying any creative work.

[0028] Figure 1 This is a schematic structural diagram of the detection device provided by the present invention. DETAILED DESCRIPTION

[0029] In order to make the objectives, technical solutions and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with examples. The illustrative embodiments of the present invention and their descriptions are only used to explain the present invention and are not intended to limit the present invention.

[0030] In the following description, numerous specific details are set forth to provide a thorough understanding of the present invention. However, it will be apparent to one of ordinary skill in the art that these specific details are not necessarily required to practice the present invention. In other embodiments, well-known materials or methods are not specifically described to avoid obscuring the present invention.

[0031] Throughout this specification, references to "one embodiment," "an embodiment," "an example," or "an example" mean that a particular feature, structure, or characteristic described in connection with the embodiment or example is included in at least one embodiment of the present invention. Thus, appearances of the phrases "one embodiment," "an embodiment," "an example," or "an example" in various places throughout this specification are not necessarily all referring to the same embodiment or example. Furthermore, the particular features, structures, or characteristics may be combined in any suitable combinations and / or subcombinations in one or more embodiments or examples. As used herein, the term "and / or" includes any and all combinations of one or more of the associated listed items.

[0032] The "ranges" disclosed herein are defined in terms of lower and upper limits, where a given range is defined by selecting a lower limit and an upper limit, and the selected lower and upper limits define the boundaries of the particular range. Ranges defined in this manner can be inclusive or exclusive of the end values ​​and can be combined arbitrarily, i.e., any lower limit can be combined with any upper limit to form a range. For example, if ranges of 60 to 120 and 80 to 110 are listed for a particular parameter, it is understood that ranges of 60 to 110 and 80 to 120 are also contemplated. Furthermore, if minimum range values ​​of 1 and 2 are listed, and if maximum range values ​​of 3, 4, and 5 are listed, the following ranges are all contemplated: 1 to 3, 1 to 4, 1 to 5, 2 to 3, 2 to 4, and 2 to 5. In this application, unless otherwise indicated, the numerical range "a to b" is a shorthand representation of any combination of real numbers between a and b, where a and b are both real numbers. For example, a numerical range of "0-5" indicates that all real numbers between "0-5" are listed herein, and "0-5" is simply an abbreviation for these numerical combinations. Furthermore, when a parameter is expressed as an integer ≥ 2, this is equivalent to disclosing that the parameter is, for example, an integer of 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, etc.

[0033] Example 1 An embodiment of the present invention provides a device for detecting dissolved gas in insulating oil, comprising a rapid degassing module and an analysis module; The rapid degassing module includes a sample bottle, a heated oil sample pool, a stirring structure, a high-purity gas storage tank, and a cold trap; The sample bottle is used to inject the insulating oil sample to be tested; The heating oil sample pool is used to heat the insulating oil sample in the sample bottle; The stirring structure is used to stir the insulating oil sample in the sample bottle; The high-purity gas storage tank is used to pass inert gas into the sample bottle to accelerate the discharge of dissolved gas in the insulating oil sample; The cold trap is used to enrich the mixed gas discharged from the sample bottle, selectively adsorb and enrich the target gas to be detected; The analysis module is used to detect the gas analyzed from the cold trap.

[0034] The detection device of the present invention can achieve rapid removal of dissolved gas in insulating oil by simultaneously heating and stirring, gas purging and replacing, and cold trap enrichment of the insulating oil sample to be tested. The degassing time is shortened to within 5 minutes, greatly improving the degassing processing efficiency.

[0035] The present invention adds a method of blowing inert gas into the oil sample on the basis of degassing by a traditional heating and shaking device. Since the solubility of inert gas in insulating oil is extremely low, microbubbles of 0.1-0.3 mm will be generated in the oil sample. The microbubbles have a large gas-liquid contact area. As the microbubbles rise in the oil sample, the dissolved gas will diffuse from the oil phase to the surface of the microbubbles, and then transfer at the gas-liquid interface. At the same time, the rising microbubbles will generate eddies in the oil sample, destroying the oil film resistance layer, so that the dissolved gas enters the microbubbles from the oil phase and is finally discharged as the bubbles move upward. Through continuous replacement, the oil sample can be quickly degassed. In addition, the continuous blowing of the inert gas will also reduce the partial pressure of the target gas in the gas phase, causing it to gradually approach zero, further promoting the removal of dissolved gas.

[0036] Conventional heating oscillations are usually performed at a frequency of 2-5 times / minute in a static thermodynamic equilibrium state, while the present application uses a dynamic thermodynamic non-equilibrium state to continuously introduce gas for displacement to form a partial pressure difference. At the same time, the bubbles will continue to burst in the oil phase to form micro-vibrations of 120-150 times / minute, thereby increasing the degassing rate.

[0037] In a specific embodiment, the components of the rapid degassing module and the analysis modules are connected by transmission lines, the transmission lines are made of inert metal, and the temperature inside the transmission lines is maintained at 100-200°C.

[0038] The present invention integrates the entire device into a closed structure through the transmission pipeline, which can avoid gas transmission losses and achieve integrated degassing detection. Furthermore, the transmission line uses an inert metal tube and is heated at 100-200°C throughout the process, which can reduce the adsorption effect of dissolved gas on the metal tube and further avoid gas transmission losses.

[0039] In one embodiment, the analysis module utilizes a gas chromatography-mass spectrometer (GC-MS). This method enables precise qualitative analysis using characteristic mass spectrometry ion fragments (e.g., m / z 26 corresponds to C2H2). Combined with the GS-GASPRO chromatographic column system, this method resolves the peak overlap problem associated with traditional GC methods, reducing quantitative repeatability (RSD) to less than 5%.

[0040] In a specific embodiment, a water trap is further provided between the sample bottle and the cold trap, and the water trap is used to capture moisture in the mixed gas discharged from the sample bottle.

[0041] In a specific embodiment, the inert gas is nitrogen or helium with a purity of ≥99.999%, and the technical indicators are as follows: oxygen <0.5ppm, water <1ppm, and gaseous hydrocarbons <0.1ppm, so as to avoid oxidation reactions in the transmission line.

[0042] In a specific embodiment, a mass flow meter is further provided between the high-purity gas storage tank and the sample bottle.

[0043] In a specific embodiment, a porous filler is provided in the cold trap, wherein the porous filler is made of carbon molecular sieve material with a maximum of 400m 2 / g specific surface area, and a pore size gradient distribution of 60-80nm, which greatly improves the gas adsorption capacity compared with traditional glass microsphere fillers.

[0044] In a specific embodiment, a silicon-based molecular sieve membrane is provided inside the transmission line, which can achieve selective water permeability and solve the problem of water interference in analysis.

[0045] In a specific embodiment, a 40 kHz high-frequency ultrasonic field is applied to the heated oil sample pool, thereby increasing the desorption rate of C2H2 in the insulating oil.

[0046] Among them, the water trap, cold trap, and GC-MS are connected through a six-way valve, and the six channels of the six-way valve are marked as 1, 2, 3, 4, 5, and 6 respectively.

[0047] like Figure 1 As shown, high-purity inert gas in the high-purity gas storage tank is introduced into the sample bottle through the transmission line. The oil sample in the sample bottle is heated and stirred at the same time, and the dissolved gas is discharged from the insulating oil to obtain a mixed gas. The mixed gas removes water through the dehydration trap and then enters the cold trap through channels 4 and 5 (1 and 6 are closed at this time). The remaining gas is discharged through 2 and 3. After the cold trap is enriched, channels 3 and 4 are closed, and channels 1, 2, 5, and 6 are opened. The cold trap is heated, the gas is desorbed, and an inert gas such as helium is introduced from channel 6. The desorbed gas is purged into the GC-MS for detection. After the detection is completed, an inert gas is introduced from channel 6 to purify the entire transmission line.

[0048] Example 2 An embodiment of the present invention provides a method for detecting dissolved gas in insulating oil, comprising the following steps: (1) Pour an appropriate amount of the oil sample to be tested into the sample bottle, then place it into the heated oil sample pool for heating and start the stirring device; (2) Continuously introduce high-purity inert gas into the sample bottle for 30-300 seconds; (3) The displaced mixed gas is first passed into a water removal trap to remove water from the gas, and then passed into a -30°C cold trap for adsorption enrichment of the target gas; (4) The enrichment cold trap is heated to achieve decomposition of the mixed gas, and then transmitted to a gas chromatography-mass spectrometer for analysis and detection.

[0049] In a specific embodiment, the heating temperature in step (1) is 50-100°C.

[0050] In a specific embodiment, the flow rate of the inert gas introduced into the sample bottle in step (2) is 20-300 ml / min.

[0051] In a specific embodiment, the heating temperature of the water removal trap in step (3) is 60-250°C, preferably 180°C; the heating temperature of the enrichment cold trap in step (4) is 60-300°C, preferably 240°C.

[0052] The specific operating method of the present invention is as follows: (1) Preheating: First, heat the transmission line of the entire device to 120°C, precool the trap to -30°C, and preheat the water trap to 180°C; (2) Preparation of the gas path in the transmission line: First, perform a gas leak test, then use a trap to enrich the inert carrier gas to increase its purity to ≥99.999%, and set a mass flow meter to accurately adjust the flow rate to 20-300 ml / min; (3) Oil sample loading stage: inject the oil sample to be tested (10-30 ml) into the constant temperature oil sample pool; heat the oil sample pool to the set temperature (50-100 °C), start magnetic stirring, and establish oil sample micro-turbulence; (4) Dynamic replacement stage: (1) Open the carrier gas passage, and inert gas is introduced into the oil sample to form microbubbles. The gas flows out with the carrier inert gas. The replacement time is 30-300s. The dissolved gas in the insulating oil is desorbed by the inert gas through heating and dynamic purging. (5) Gas capture stage: The displaced mixed gas is captured by the water removal trap at the front end of the cold trap and enters the -30℃ cold trap. From the start of the timing to the end of the enrichment, the entire time takes 180 seconds, which is the gas removal and replacement time; (6) Desorption and sampling: After gas removal is completed, the desorption and sampling are ready, the timing is started, the enrichment cold trap is quickly heated to 240 °C, and the desorbed gas is purged into the GC-MS for detection by inert gas, which takes 300 s. (7) Pipeline purification: Finally, the transmission line is purged with new high-purity inert gas; the system is ready for the next replacement cycle.

[0053] Traditional methods (such as GB / T17623) use a single constant temperature (usually 50°C) oscillation degassing, with a degassing time of 32±5 minutes and an equipment energy consumption of 2.4kWh; the rapid degassing module of the present invention adopts a gradient temperature control method as a whole, specifically: the transmission line: 100-200°C (maintaining the gas state), the heating pool: 50-100°C (80°C optimal), the cold trap temperature: -30°C (adsorption stage) / 240°C (desorption stage), and then combined with high-purity inert gas purging, it can synergistically increase the degassing kinetic efficiency by 3 times, the degassing time is 4.2±0.3 minutes, the equipment energy consumption is 0.8kWh, and combined with the GC-MS analysis and detection time, the overall single sample detection time only takes 15 minutes to complete.

[0054] The specific parameters of the GCMS device for analysis and detection are as follows: injection port: 150°C; split ratio: 1, column flow rate 1.6 ml / min; program temperature: 40°C (2 min) 5°C / min 60°C 20°C / min 120°C (4 min); ion source temperature: 200°C, transfer line temperature: 200°C, scanning mode, full scan: 10-70 amu.

[0055] The specific implementation methods described above further illustrate the objectives, technical solutions and beneficial effects of the present invention in detail. It should be understood that the above description is only a specific implementation method of the present invention and is not intended to limit the scope of protection of the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. A device for detecting dissolved gas in insulating oil, characterized in that: Includes fast degassing module and analysis module; The rapid degassing module includes a sample bottle, a heated oil sample pool, a stirring structure, a high-purity gas storage tank, and a cold trap; The sample bottle is used to inject the insulating oil sample to be tested; The heating oil sample pool is used to heat the insulating oil sample in the sample bottle; The stirring structure is used to stir the insulating oil sample in the sample bottle; The high-purity gas storage tank is used to pass inert gas into the sample bottle to accelerate the discharge of dissolved gas in the insulating oil sample; The cold trap is used to enrich the mixed gas discharged from the sample bottle, and selectively adsorb and enrich the target gas to be detected; The analysis module is used to detect the gas analyzed from the cold trap.

2. A detection device for dissolved gas in insulating oil according to claim 1, characterized in that: The components of the rapid degassing module and the analysis modules are connected by transmission lines. The transmission lines are made of inert metal and the temperature inside the transmission lines is maintained at 100-200°C.

3. The device for detecting dissolved gas in insulating oil according to claim 1, characterized in that: The analysis module adopts a gas chromatography-mass spectrometer.

4. The device for detecting dissolved gas in insulating oil according to claim 1, characterized in that: A dewatering trap is further provided between the sample bottle and the cold trap, and the dewatering trap is used to capture moisture in the mixed gas discharged from the sample bottle.

5. The device for detecting dissolved gas in insulating oil according to claim 1, characterized in that: The inert gas is nitrogen or helium with a purity of ≥99.999%.

6. The device for detecting dissolved gas in insulating oil according to claim 1, characterized in that: A mass flow meter is also provided between the high-purity gas storage tank and the sample bottle.

7. A method for detecting dissolved gas in insulating oil, characterized in that: The steps include: (1) Pour an appropriate amount of the oil sample to be tested into the sample bottle, then place it into the heated oil sample pool for heating and start the stirring device; (2) Continuously introduce high-purity inert gas into the sample bottle for 30-300 seconds; (3) The displaced mixed gas is first passed into a water removal trap to remove water from the gas, and then passed into a -30°C cold trap for adsorption enrichment of the target gas; (4) The enrichment cold trap is heated to achieve decomposition of the mixed gas, and then transmitted to a gas chromatography-mass spectrometer for analysis and detection.

8. The device for detecting dissolved gas in insulating oil according to claim 3, characterized in that: The heating temperature in step (1) is 50-100°C.

9. The device for detecting dissolved gas in insulating oil according to claim 3, characterized in that: The flow rate of the inert gas introduced into the sample bottle in step (2) is 20-300 ml / min.

10. The device for detecting dissolved gas in insulating oil according to claim 3, characterized in that: The heating temperature of the water removal trap in step (3) is 60-250°C; the heating temperature of the enrichment cold trap in step (4) is 60-300°C.

Images