Gas chromatograph and detection control method thereof

Abstract

The application discloses a gas chromatograph and a detection control method thereof. The gas chromatograph comprises a first separation module, a second separation module, a detection module and a reversing valve. The first separation module is used for separating a first batch of measurement components in a to-be-detected gas and a second batch of measurement components in the to-be-detected gas, and temporarily storing a third batch of measurement components in the to-be-detected gas. The second separation module is used for separating the first batch of measurement components in the to-be-detected gas and temporarily storing the second batch of measurement components. The detection module is used for detecting the content of the components in the to-be-detected gas. The reversing valve is used for switching the content detection of the first batch of measurement components, the second batch of measurement components and the third batch of measurement components. The first separation module and the second separation module are integrated into a single gas chromatograph, and the content of the first batch of measurement components, the second batch of measurement components and the third batch of measurement components in the to-be-detected gas is switched by the reversing valve, so that the one-time detection of the components in the to-be-detected gas is realized.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of chromatography, in particular to a gas chromatograph and a detection control method thereof. BACKGROUND

[0002] As an important analytical instrument, gas chromatographs have been widely used in various fields such as chemistry, environment, energy, and power. Traditional gas chromatographs are usually designed for analyzing specific types of gas samples. By selecting appropriate chromatographic columns, molecular sieves, and carrier gases, effective separation and detection of components in gas samples can be achieved. However, with the continuous progress of science and technology and the increasing diversification of industrial production needs, higher requirements are placed on the analysis capabilities and flexibility of gas chromatographs.

[0003] In the field of transformer equipment fault diagnosis, gas composition analysis in insulating oil is an important means to determine the operating state of the transformer equipment and predict faults. Insulating oil is a complex mixture composed of various hydrocarbons with different molecular weights. In the case of discharge or overheating, some C-H or C-C bonds in the insulating oil may break, releasing active hydrogen atoms and unstable hydrocarbons. These substances then undergo a series of complex chemical reactions, generating characteristic fault gases such as hydrogen, methane, ethane, ethylene, and acetylene. Power workers can assess the health of the transformer by monitoring the content of these characteristic fault gases. At the same time, if the transformer's oil reservoir, body, pipeline, flange, and other components are not tightly sealed, air may seep in, causing the oxygen and nitrogen content in the insulating oil to rise. The national standard has clear provisions for the total gas content in insulating oil to ensure the safe operation of the transformer. Therefore, power workers monitor the total gas content in insulating oil, including the content of hydrogen, oxygen, and nitrogen, to determine the sealing performance of the transformer equipment.

[0004] A gas chromatograph is an instrument specifically designed to monitor fault gas components in insulating oil. It determines the fault type, fault location, and severity of the transformer equipment through auxiliary analysis. The detection principle of this instrument is based on gas chromatography, a technique that separates based on time differences. In gas chromatography, a gaseous mixture or gas is passed through a chromatographic column containing specific substances, and different compounds are separated due to the different adsorption properties of the substances in the chromatographic column. The peak appearance time of each component, i.e., the retention time, is used for qualitative identification of each component, while the size of the peak, whether it is the peak height or the peak area, is an indicator of the content of the component. In this way, the gas chromatograph can accurately analyze the characteristic gases in the insulating oil, providing important data for the maintenance and fault diagnosis of the transformer equipment.

[0005] Traditional gas chromatographs, when analyzing gases in insulating oil, often only analyze specific fault characteristic gases and cannot simultaneously detect the total content of multiple fault characteristic gases. This limits their accuracy and comprehensiveness in fault diagnosis. Currently, many users in China who use gas chromatographs to detect fault characteristic gas content in insulating oil typically require two instruments: one equipped with a chromatographic column to measure fault characteristic gases such as H2, CH4, C2H6, C2H4, C2H2, CO, and CO2; and the other equipped with a molecular sieve to measure the content of H2, O2, and N2. The contents of each fault gas are then summed to determine the total gas content in the insulating oil. The original instrument design was single-function and lacked redundancy. If an instrument malfunctioned, it would affect normal sample detection, and both instruments were required to measure the total gas content. Furthermore, traditional carrier gases such as nitrogen cannot meet the analytical requirements for accurate detection of nitrogen in insulating oil, necessitating the search for more suitable carrier gas alternatives. Summary of the Invention

[0006] The technical problem to be solved by the present invention is to address at least one defect of the related technologies mentioned in the background: when detecting the total gas content of multiple fault characteristic gases, two gas chromatographs must be used simultaneously to complete the measurement, and to provide a gas chromatograph and its detection and control method.

[0007] The technical solution adopted by this invention to solve its technical problem is: to construct a gas chromatograph, comprising:

[0008] The first separation module is used to separate the first batch of measuring components and the second batch of measuring components in the gas to be tested and allow the first batch of measuring components and the second batch of measuring components to pass through, and temporarily store the third batch of measuring components in the gas to be tested.

[0009] The second separation module is used to separate the first batch of measuring components from the gas to be tested and allow the first batch of measuring components to pass through, and temporarily store the second batch of measuring components.

[0010] The detection module is used to detect the component content in the gas to be tested; and,

[0011] A reversing valve is used to switch the content detection of the first batch of measuring components, the second batch of measuring components, and the third batch of measuring components. The reversing valve includes a first valve port, a second valve port, a third valve port, a fourth valve port, a fifth valve port, and a sixth valve port.

[0012] The outlet end of the first separation module is connected with the first valve port, the inlet end of the second separation module is connected with the second valve port, the outlet end of the second separation module is connected with the third valve port, the fourth valve port is connected with the fifth valve port, and the inlet end of the detection module is connected with the sixth valve port.

[0013] In some embodiments, when the first valve port is in communication with the second valve port, the second valve port is in communication with the third valve port through the second separation module, the third valve port is in communication with the sixth valve port, and the fourth valve port is in communication with the fifth valve port, the first batch of measurement components and the second batch of measurement components are separated from the to-be-detected gas after passing through the first separation module, the first batch of measurement components are separated from the first batch of measurement components after passing through the first valve port, the second valve port, and the second separation module, and the first batch of measurement components enter the detection module after passing through the third valve port and the sixth valve port, thereby forming a detection path for detecting the content of the first batch of measurement components in the to-be-detected gas.

[0014] When the first valve port is in communication with the fourth valve port, the second valve port is in communication with the third valve port, the fourth valve port is in communication with the fifth valve port, and the fifth valve port is in communication with the sixth valve port, the third batch of measurement components temporarily stored in the first separation module in the to-be-detected gas enter the detection module after passing through the first separation module, the first valve port, the fourth valve port, the fifth valve port, and the sixth valve port, thereby forming a detection path for detecting the content of the third batch of measurement components in the to-be-detected gas.

[0015] When the first valve port is in communication with the second valve port, the second valve port is in communication with the third valve port through the second separation module, the third valve port is in communication with the sixth valve port, and the fourth valve port is in communication with the fifth valve port, the second batch of measurement components temporarily stored in the second separation module in the to-be-detected gas enter the detection module after passing through the second separation module, the third valve port, and the sixth valve port, thereby forming a detection path for detecting the content of the second batch of measurement components in the to-be-detected gas.

[0016] In some embodiments, the gas chromatograph further comprises:

[0017] A sample loading module is configured to carry the to-be-detected gas into the first separation module, and the outlet end of the sample loading module is connected with the inlet end of the first separation module.

[0018] In some embodiments, the sample loading module comprises:

[0019] A sample gas unit is configured to introduce the to-be-detected gas, and the outlet end of the sample gas unit is connected with the inlet end of the first separation module.

[0020] a carrier gas unit configured to introduce a carrier gas to carry the gas to be measured, the carrier gas being argon, an outlet end of the carrier gas unit being connected to an inlet end of the first separation module.

[0021] In some embodiments, the first valve port is in communication with the second valve port, the second valve port is in communication with the third valve port via the second separation module, the third valve port is in communication with the sixth valve port, the fourth valve port is in communication with the fifth valve port, and the carrier gas enters the detection module via the first separation module, the first valve port, the second valve port, the second separation module, the third valve port, and the sixth valve port, forming a preparation path of the carrier gas.

[0022] In some embodiments, the gas chromatograph further comprises:

[0023] a damping module configured to control a flow rate of the gas to be measured, an inlet end of the damping module being connected to the fourth valve port, and an outlet end of the damping module being connected to the fifth valve port.

[0024] In some embodiments, the detection module comprises:

[0025] a first detection unit configured to detect components of the gas to be measured after separation;

[0026] a conversion unit configured to convert the components of the gas to be measured after separation to obtain converted components of the gas to be measured;

[0027] a second detection unit configured to detect the converted components of the gas to be measured; and

[0028] a data processing unit configured to process detection data of the first detection unit and the second detection unit.

[0029] wherein the sixth valve port is connected to an inlet end of the first detection unit, an outlet end of the first detection unit is connected to an inlet end of the conversion unit, and an outlet end of the conversion unit is connected to an inlet end of the second detection unit.

[0030] The data processing unit is communicatively connected to the first detection unit and the second detection unit.

[0031] In some embodiments, the first batch of measured components comprises at least one gas of the following chemical formula: H2;

[0032] The second batch of measured components comprises at least one gas of the following chemical formula: CO, CH4, O2, N2;

[0033] The third batch of measurement components includes at least one gas of the following chemical formula: CO2, C2H2, C2H4, C2H6.

[0034] The application also discloses a detection control method applied to the gas chromatograph.

[0035] First batch of measurement component detection: the first valve port is controlled to be communicated with the second valve port, the second valve port is communicated with the third valve port through the second separation module, the third valve port is communicated with the sixth valve port, and the fourth valve port is communicated with the fifth valve port, so that a detection path for detecting the first batch of measurement component content in the to-be-detected gas is switched, and the first batch of measurement component content in the to-be-detected gas is detected.

[0036] Third batch of measurement component detection: after the first batch of measurement component detection is completed, the first valve port is controlled to be communicated with the fourth valve port, the second valve port is communicated with the third valve port, the fourth valve port is communicated with the fifth valve port, and the fifth valve port is communicated with the sixth valve port, so that a detection path for detecting the third batch of measurement component content in the to-be-detected gas is switched, and the third batch of measurement component content in the to-be-detected gas is detected.

[0037] Second batch of measurement component detection: after the third batch of measurement component detection is completed, the first valve port is controlled to be communicated with the second valve port, the second valve port is communicated with the third valve port through the second separation module, the third valve port is communicated with the sixth valve port, the fourth valve port is communicated with the fifth valve port, so that a detection path for detecting the second batch of measurement component content in the to-be-detected gas is switched, and the second batch of measurement component content in the to-be-detected gas is detected.

[0038] In some embodiments, the first batch of measurement component detection further includes the following steps before the first batch of measurement component detection:

[0039] Gas chromatograph preparation step: self-detection is performed, the first valve port is controlled to be communicated with the second valve port, the second valve port is communicated with the third valve port through the second separation module, the third valve port is communicated with the sixth valve port, the fourth valve port is communicated with the fifth valve port, so that a preparation path for carrier gas is switched, and the carrier gas is introduced.

[0040] By implementing the application, the following beneficial effects are achieved:

[0041] The application integrates the first separation module and the second separation module into a single gas chromatograph, and uses a reversing valve to switch the content of the first batch of measured components, the second batch of measured components and the third batch of measured components in the measured gas, so that the gas chromatograph can detect the components of the measured gas once in a single sampling process, which significantly improves the detection efficiency. This design reduces the sampling amount and analysis workload of the measured gas, effectively reducing time and cost. At the same time, the gas chromatograph can complete the analysis of complex samples in a short time due to its high separation efficiency and fast analysis capability. BRIEF DESCRIPTION OF DRAWINGS

[0042] The application will be further described below in conjunction with the drawings and examples, wherein:

[0043] Figure 1 Fig. 1 shows a first internal communication state schematic diagram of the reversing valve in an embodiment of the gas chromatograph of the application;

[0044] Figure 2 Fig. 2 shows a second internal communication state schematic diagram of the reversing valve in an embodiment of the gas chromatograph of the application;

[0045] Figure 3 Fig. 3 shows a quality control gas analysis spectrum before modification in an embodiment of the gas chromatograph of the application;

[0046] Figure 4 Fig. 4 shows a quality control gas analysis spectrum after modification in an embodiment of the gas chromatograph of the application;

[0047] Figure 5 Fig. 5 shows the analysis results of the same gas chromatograph before and after modification in an embodiment of the gas chromatograph of the application. DETAILED DESCRIPTION

[0048] In order to have a clearer understanding of the technical features, objectives and effects of the application, the specific embodiments of the application will be described in detail with reference to the drawings.

[0049] It should be noted that the flowchart shown in the drawings is only illustrative, and does not necessarily include all the contents and operations / steps, nor does it necessarily execute in the order described. For example, some operations / steps can be further divided, and some operations / steps can be combined or partially combined, so the actual execution order may be changed according to the actual situation.

[0050] The block diagram shown in the drawings is only a functional entity, which does not necessarily correspond to a physically independent entity. That is, these functional entities can be implemented in software form, or in one or more hardware modules or integrated circuits, or in different networks and / or processor devices and / or microcontroller devices.

[0051] Some embodiments of the present application disclose a gas chromatograph, comprising a first separation module 1, a second separation module 2, a detection module 3 and a switching valve 4, specifically as follows:

[0052] The first separation module 1 is used for separating and passing a first batch of measured components in the measured gas and a second batch of measured components in the measured gas, and temporarily storing a third batch of measured components in the measured gas. The second separation module 2 is used for separating and passing the first batch of measured components in the measured gas, and temporarily storing the second batch of measured components. The detection module 3 is used for detecting the content of components in the measured gas.

[0053] The switching valve 4 is used for switching the content detection of the first batch of measured components, the second batch of measured components and the third batch of measured components. The switching valve 4 comprises a first valve port 41, a second valve port 42, a third valve port 43, a fourth valve port 44, a fifth valve port 45 and a sixth valve port 46.

[0054] The outlet end of the first separation module 1 is connected with the first valve port 41, the inlet end of the second separation module 2 is connected with the second valve port 42, the outlet end of the second separation module 2 is connected with the third valve port 43, the fourth valve port 44 is connected with the fifth valve port 45, and the inlet end of the detection module 3 is connected with the sixth valve port 46.

[0055] In some embodiments, the first separation module 1 is a chromatographic column, which is used for separating and passing the first batch of measured components in the measured gas and the second batch of measured components in the measured gas, and temporarily storing the third batch of measured components in the measured gas.

[0056] The second separation module 2 is a molecular sieve, which is used for separating and passing the first batch of measured components in the measured gas, and temporarily storing the second batch of measured components.

[0057] The measured gas refers to a gas used for judging whether there is a characteristic gas of insulating oil fault in a transformer device filled with insulating oil, and the characteristic gas of insulating oil fault includes at least one of H2, CO, CH4, O2, N2, CO2, C2H2, C2H4 and C2H6. The first batch of measured components includes at least one gas of the following chemical formula: H2. The second batch of measured components includes at least one gas of the following chemical formula: CO, CH4, O2, N2. The third batch of measured components includes at least one gas of the following chemical formula: CO2, C2H2, C2H4, C2H6. It can be understood that at least one can be one, two, three or any number. Preferably, the first batch of measured components includes a gas of the following chemical formula: H2. The second batch of measured components includes a gas of the following chemical formula: CO, CH4, O2, N2. The third batch of measured components includes a gas of the following chemical formula: CO2, C2H2, C2H4, C2H6.

[0058] In some embodiments, the reversing valve 4 is used to switch the content detection of the first batch of measurement components, the second batch of measurement components and the third batch of measurement components, and the reversing valve 4 includes a first valve port 41, a second valve port 42, a third valve port 43, a fourth valve port 44, a fifth valve port 45 and a sixth valve port 46.

[0059] Wherein, the reversing valve 4 has two internal communication states, as shown in the following table: Figure 1 The first internal communication state is that the first valve port 41 and the second valve port 42 are communicated, the third valve port 43 and the sixth valve port 46 are communicated, and the fourth valve port 44 and the fifth valve port 45 are communicated.

[0060] The second internal communication state is that the first valve port 41 and the fourth valve port 44 are communicated, the second valve port 42 and the third valve port 43 are communicated, and the fifth valve port 45 and the sixth valve port 46 are communicated. Figure 2 For example, the reversing valve 4 is a six-way valve, and nitrogen is used as the power source of the six-way valve to provide power for the six-way valve to switch the internal communication state. The six-way valve is only an example and does not limit the present application. Other valves can also be used.

[0061] In some embodiments, as shown in the following table, when the first valve port 41 is communicated with the second valve port 42, the second valve port 42 is communicated with the third valve port 43 through the second separation module 2, the third valve port 43 is communicated with the sixth valve port 46, and the fourth valve port 44 is communicated with the fifth valve port 45, the carrier gas enters the detection module 3 through the first separation module 1, the first valve port 41, the second valve port 42, the second separation module 2, the third valve port 43 and the sixth valve port 46, forming a preparation path of the carrier gas.

[0062] Figure 1 As shown in the following table, when the first valve port 41 is communicated with the second valve port 42, the second valve port 42 is communicated with the third valve port 43 through the second separation module 2, the third valve port 43 is communicated with the sixth valve port 46, and the fourth valve port 44 is communicated with the fifth valve port 45, the first batch of measurement components and the second batch of measurement components are separated from the first separation module 1, the first batch of measurement components and the second batch of measurement components are separated from the first valve port 41, the second valve port 42 and the second separation module 2, the first batch of measurement components enters the detection module 3 through the third valve port 43 and the sixth valve port 46, forming a detection path of the first batch of measurement components in the detection gas.

[0063] As shown in the following table, when the first valve port 41 is communicated with the second valve port 42, the second valve port 42 is communicated with the third valve port 43 through the second separation module 2, the third valve port 43 is communicated with the sixth valve port 46, and the fourth valve port 44 is communicated with the fifth valve port 45, the first batch of measurement components and the second batch of measurement components are separated from the first separation module 1, the first batch of measurement components and the second batch of measurement components are separated from the first valve port 41, the second valve port 42 and the second separation module 2, the first batch of measurement components enters the detection module 3 through the third valve port 43 and the sixth valve port 46, forming a detection path of the first batch of measurement components in the detection gas. Figure 1 As shown in the following table, when the first valve port 41 is communicated with the second valve port 42, the second valve port 42 is communicated with the third valve port 43 through the second separation module 2, the third valve port 43 is communicated with the sixth valve port 46, and the fourth valve port 44 is communicated with the fifth valve port 45, the first batch of measurement components and the second batch of measurement components are separated from the first separation module 1, the first batch of measurement components and the second batch of measurement components are separated from the first valve port 41, the second valve port 42 and the second separation module 2, the first batch of measurement components enters the detection module 3 through the third valve port 43 and the sixth valve port 46, forming a detection path of the first batch of measurement components in the detection gas.

[0064] Figure 2 ​​As shown, when the first valve port 41 is connected to the fourth valve port 44, the second valve port 42 is connected to the third valve port 43, the fourth valve port 44 is connected to the fifth valve port 45, and the fifth valve port 45 is connected to the sixth valve port 46, the third batch of measuring components temporarily present in the first separation module 1 in the gas to be tested enters the detection module 3 after passing through the first separation module 1, the first valve port 41, the fourth valve port 44, the fifth valve port 45, and the sixth valve port 46, forming a detection path for detecting the content of the third batch of measuring components in the gas to be tested.

[0065] like Figure 1 As shown, when the first valve port 41 is connected to the second valve port 42, the second valve port 42 is connected to the third valve port 43 via the second separation module 2, the third valve port 43 is connected to the sixth valve port 46, and the fourth valve port 44 is connected to the fifth valve port 45, the second batch of measuring components temporarily present in the second separation module 2 in the gas to be tested enters the detection module 3 after passing through the second separation module 2, the third valve port 43 and the sixth valve port 46, forming a detection path for detecting the content of the second batch of measuring components in the gas to be tested.

[0066] In some embodiments, the gas chromatograph further includes a sample loading module 5, which is used to carry the gas to be tested into the first separation module 1 with a carrier gas, and the outlet end of the sample loading module 5 is connected to the inlet end of the first separation module 1.

[0067] In some embodiments, the sample carrying module 5 includes a sample gas unit 51 and a carrier gas unit 52. The sample gas unit 51 is used to introduce the gas to be tested, and the outlet end of the sample gas unit 51 is connected to the inlet end of the first separation module 1. The carrier gas unit 52 is used to introduce a carrier gas to carry the gas to be tested. The carrier gas is argon, and the outlet end of the carrier gas unit 52 is connected to the inlet end of the first separation module 1.

[0068] In some embodiments, the gas chromatograph further includes a damping module 6, which is used to control the flow rate of the gas to be measured. The inlet end of the damping module 6 is connected to the fourth valve port 44, and the outlet end of the damping module 6 is connected to the fifth valve port 45.

[0069] In some embodiments, such as Figure 1 As shown, the detection module 3 includes a first detection unit 31, a conversion unit 32, a second detection unit 33, and a data processing unit 34, as detailed below:

[0070] The first detection unit 31 is used to detect the components obtained after separation of the test gas. The conversion unit 32 is used to convert the components obtained after separation of the test gas to obtain the converted components of the test gas. The second detection unit 33 is used to detect the converted components of the test gas. The data processing unit 34 is used to process the detection data of the first detection unit 31 and the second detection unit 33.

[0071] The sixth valve port 46 is connected with the inlet end of the first detection unit 31, the outlet end of the first detection unit 31 is connected with the inlet end of the conversion unit 32, and the outlet end of the conversion unit 32 is connected with the inlet end of the second detection unit 33. The data processing unit 34 is in communication connection with the first detection unit 31 and the second detection unit 33.

[0072] In some embodiments, the first detection unit 31 is a thermal conductivity detector (TCD). When the to-be-detected gas passes through the thermal conductivity detector, due to the difference in thermal conductivity between the to-be-detected gas and the carrier gas, the temperature of the heating wire changes, which causes the resistance of the heating wire to change, and then the change is measured and converted into a signal. The thermal conductivity detector (TCD) is only an example and does not limit the present application. It can also be other.

[0073] In some embodiments, the conversion unit 32 is a nickel converter, which is used to convert carbon monoxide and carbon dioxide into methane, thereby improving the detection sensitivity of the flame ionization detector (FID) to carbon monoxide and carbon dioxide. The nickel converter is only an example and does not limit the present application. It can also be other.

[0074] In some embodiments, the second detection unit 33 is a flame ionization detector (FID). The working principle of the flame ionization detector is to generate a flame in a mixture of hydrogen and air, introduce the to-be-detected substance into the flame, make it undergo an oxidation reaction and produce ionization, and then the ions are detected by an ionization detector to generate a weak current, which is amplified and converted into a voltage signal for recording and processing the detection results. The flame ionization detector (FID) is only an example and does not limit the present application. It can also be other.

[0075] Some embodiments of the present application also disclose a detection control method of the gas chromatograph of any one of the above-mentioned embodiments, which comprises: a first batch of measurement component detection step, a third batch of measurement component detection step and a second batch of measurement component detection step, and specifically as follows:

[0076] The first batch of measurement component detection step: the first valve port 41 is controlled to be in communication with the second valve port 42, the second valve port 42 is in communication with the third valve port 43 through the second separation module 2, the third valve port 43 is in communication with the sixth valve port 46, and the fourth valve port 44 is in communication with the fifth valve port 45, so as to switch to a detection path for detecting the content of the first batch of measurement components in the to-be-detected gas, and detect the content of the first batch of measurement components in the to-be-detected gas;

[0077] The third batch of measuring component detection steps: After the first batch of measuring components is detected, control the first valve port 41 to connect with the fourth valve port 44, the second valve port 42 to connect with the third valve port 43, the fourth valve port 44 to connect with the fifth valve port 45, and the fifth valve port 45 to connect with the sixth valve port 46, so as to switch to the detection path for detecting the content of the third batch of measuring components in the gas to be tested, and perform the detection of the content of the third batch of measuring components in the gas to be tested.

[0078] The second batch of measurement component detection steps: After the third batch of measurement component detection is completed, the first valve port 41 is connected to the second valve port 42, the second valve port 42 is connected to the third valve port 43 via the second separation module 2, the third valve port 43 is connected to the sixth valve port 46, and the fourth valve port 44 is connected to the fifth valve port 45, so as to switch to the detection path for detecting the content of the second batch of measurement components in the gas to be tested, and to detect the content of the second batch of measurement components in the gas to be tested.

[0079] For example: Figure 1 As shown, the first batch of measured components is detected as follows: the first valve port 41 is connected to the second valve port 42, the second valve port 42 is connected to the third valve port 43 via the second separation module 2, the third valve port 43 is connected to the sixth valve port 46, the fourth valve port 44 is connected to the fifth valve port 45, the sample gas unit 51 adds the gas to be measured, and the carrier gas carries the gas to be measured into the instrument for the separation and detection of each component. The first batch of measured components (H2) preferentially passes through the first separation module 1 (chromatographic column) and the second separation module 2 (molecular sieve), and is detected by the first detection unit 31 (TCD). At this time, the second batch of measured components (CO, CH4, O2, N2) is temporarily stored in the second separation module 2 (molecular sieve), and the third batch of measured components (CO2, C2H2, C2H4, C2H6) is temporarily stored in the first separation module 1 (chromatographic column).

[0080] like Figure 2 As shown, the third batch of measured components is detected: After the first batch of measured components (H2) is detected, the first valve port 41 is connected to the fourth valve port 44, the second valve port 42 is connected to the third valve port 43, the fourth valve port 44 is connected to the fifth valve port 45, and the fifth valve port 45 is connected to the sixth valve port 46. At this time, a sealed space is formed between the second separation module 2, the second valve port 42, and the third valve port 43, temporarily storing the second batch of measured components (CO, CH4, O2, N2) in the second separation module 2 (molecule). The third batch of measured components (CO2, C2H2, C2H4, C2H6) temporarily stored in the first separation module 1 (chromatographic column) is carried by the carrier gas into the downstream first detection unit 31 (TCD), conversion unit 32 (nickel conversion furnace), and second detection unit 33 (FID). The third batch of measured components (CO2, C2H2, C2H4, C2H6) is converted into CH4 in the conversion unit 32 (nickel conversion furnace) and finally the content is detected in the second detection unit 33 (FID).

[0081] As shown in Figure 1 the second batch of measurement component detection: after the detection of the third batch of measurement components (CO2, C2H2, C2H4, C2H6) is completed, the first valve port 41 is controlled to communicate with the second valve port 42, the second valve port 42 communicates with the third valve port 43 through the second separation module 2, the third valve port 43 communicates with the sixth valve port 46, the fourth valve port 44 communicates with the fifth valve port 45, at this time the closed space is opened, O2 and N2 are carried into the first detection unit 31 (TCD) by the carrier gas to detect the content, and CO and CH4 are carried into the conversion unit 32 (nickel conversion furnace) and the second detection unit 33 (FID) by the carrier gas to complete the content detection.

[0082] In some embodiments, the first batch of measurement component detection step further comprises:

[0083] Gas chromatograph preparation step: self-checking is performed, the first valve port 41 is controlled to communicate with the second valve port 42, the second valve port 42 communicates with the third valve port 43 through the second separation module 2, the third valve port 43 communicates with the sixth valve port 46, the fourth valve port 44 communicates with the fifth valve port 45, to switch to the preparation path of the carrier gas, and the carrier gas is introduced.

[0084] For example: as shown in Figure 1 after the instrument completes the start-up performance measurement and the quality control verification is qualified, the first valve port 41 is controlled to communicate with the second valve port 42, the second valve port 42 communicates with the third valve port 43 through the second separation module 2, the third valve port 43 communicates with the sixth valve port 46, the fourth valve port 44 communicates with the fifth valve port 45, to switch to the preparation path of the carrier gas, and the carrier gas is introduced, and the start-up performance measurement and the quality control verification qualified here are only examples and do not limit the present application.

[0085] The following is a specific embodiment of the present application:

[0086] The present application relates to the modification of the original gas chromatograph, mainly including the chromatographic column, the molecular sieve, the six-way valve, the ten-element standard gas, the ten-element quality control gas, the argon and the nitrogen. The core of the modification is to increase the chromatographic column or the molecular sieve in an original gas chromatograph, to switch the content of the first batch of measurement components, the second batch of measurement components and the third batch of measurement components in the detected gas by using the reversing valve, to realize the one-time detection of the components of the detected gas in a single sampling process of a gas chromatograph, and to replace the originally used nitrogen carrier gas with argon, thereby enhancing the ability of the instrument to analyze the nitrogen in the insulating oil. In addition, by re-debugging and setting the operating parameters of the instrument, the present application realizes the function of a chromatograph that can simultaneously analyze the types of fault characteristic gases and the total content of fault characteristic gases.

[0087] In the related art, the original two gas chromatographs of the power plant are equipped with a thermal conductivity detector (TCD) and a flame ionization detector (FID). Among them, the first chromatograph measures the hydrogen (H2), methane (CH4), ethylene (C2H4), ethane (C2H6), acetylene (C2H2), carbon monoxide (CO) and carbon dioxide (CO2) in the fault characteristic gas of insulating oil by installing a chromatographic column; while the second chromatograph measures the hydrogen (H2), oxygen (O2) and nitrogen (N2) content in the fault characteristic gas of insulating oil by installing a molecular sieve, and adds the fault characteristic gas content detected by the first chromatograph to obtain the total gas content of the insulating oil sample fault characteristic gas. The implementation of the modification scheme mainly follows the following seven steps:

[0088] In the first step of the modification scheme, the first chromatograph originally only has a chromatographic column without a molecular sieve, and can only analyze fault characteristic gases such as hydrogen (H2), methane (CH4), ethylene (C2H4), ethane (C2H6), acetylene (C2H2), carbon monoxide (CO) and carbon dioxide (CO2). In the modification plan, a molecular sieve is added downstream of the chromatographic column to expand its analysis capability, including oxygen (O2) and nitrogen (N2). Similarly, the second chromatograph originally only has a molecular sieve without a chromatographic column, and can only analyze hydrogen (H2), oxygen (O2) and nitrogen (N2). In the modification, a chromatographic column is added upstream of the molecular sieve to increase the analysis capability of hydrogen (H2), methane (CH4), ethylene (C2H4), ethane (C2H6), acetylene (C2H2), carbon monoxide (CO) and carbon dioxide (CO2). Through these modifications, both chromatographs can now analyze a wider range of gas components.

[0089] In the second step of the modification scheme, the carrier gas of the gas chromatograph is changed from nitrogen to argon. The main purpose of this change is to enable the chromatograph to analyze the nitrogen content in the insulating oil. If the carrier gas is not changed, the nitrogen in the insulating oil will be masked by the nitrogen as the carrier gas, resulting in inaccurate analysis. By using argon as the carrier gas, this interference can be avoided, thereby enabling effective detection of the nitrogen content in the insulating oil.

[0090] In the third step of the modification scheme, the nitrogen originally designed as the carrier gas for the first chromatograph is reconfigured to be used as the power gas source for the six-way valve. This change enables the six-way valve to obtain the required power when switching to ensure its normal operation. At the same time, the specific configuration of the six-way valve can be set and adjusted according to the actual analysis requirements to meet the operation requirements of the chromatograph under different analysis conditions.

[0091] In the fourth step of the modification plan, the calibration gas used by the chromatograph was updated. Originally, ternary and octane calibration gases were used, but now decane calibration gas was used. This new decane calibration gas is composed of nine fault characteristic gases, including hydrogen (H2), methane (CH4), ethylene (C2H4), ethane (C2H6), acetylene (C2H2), carbon monoxide (CO), carbon dioxide (CO2), oxygen (O2), and nitrogen (N2), as well as argon as a balance gas, totaling ten gases. This change allows the calibration gas to more comprehensively cover the types of gases that need to be analyzed, thereby improving the accuracy and reliability of the chromatograph analysis.

[0092] In the fifth step of the modification plan, the chromatograph needs to be re-commissioned and the operating parameters set. After adding the chromatographic column or molecular sieve, and completing the pipeline modification and carrier gas replacement, the instrument must be carefully commissioned and verified. The purpose of this process is to select the best operating parameters to ensure that the chromatograph can efficiently and accurately analyze gas samples. Parameters that need to be adjusted and optimized include furnace temperature, hydrogen flow rate, air flow rate, reference gas flow, tail blow, carrier gas flow rate, heater temperature, peak time, and detection sensitivity. The precise setting of these parameters is crucial to the performance of the chromatograph and directly affects the accuracy and repeatability of the analysis results. Through this step, it can be ensured that the chromatograph can achieve the expected analysis effect after modification.

[0093] In the sixth step of the modification plan, once the chromatograph is commissioned and verified, the next step is to use the calibration gas to recalibrate the instrument's analysis curve. This ensures that all parameters meet the required standards and requirements. After calibration is complete, the quality control gas will be used to verify the content of each component to ensure the accuracy and stability of the instrument analysis. The pre-modification quality control gas analysis spectrum can be referenced in Figure 3 , while the post-modification quality control gas analysis spectrum is shown in Figure 4 . These spectra provide a visual comparison of the modification effect, helping to evaluate whether the modification is successful and whether the instrument performance has improved. Through this step, it can be confirmed whether the chromatograph can meet the functional requirements of analyzing fault characteristic gases and total gas content after modification.

[0094] In the seventh step of the modification scheme, actual sample measurements and comparative verification of the modified chromatograph are required. The purpose of this step is to ensure that the modified chromatograph can provide accurate and reliable data in actual application. For this purpose, different samples of the same transformer equipment will be monitored and the data before and after modification will be compared (represented in white background). If the fluctuations of each parameter are small and consistent with historical trends, it indicates that the modification is successful. The data after modification (represented in gray background) generally shows a slow upward trend, which is consistent with the extension of the transformer operating time and the natural growth of gas content, which is a normal phenomenon. The specific analysis results of the same gas chromatograph before and after modification can be seen in the following table Figure 5 This table provides detailed data comparison to verify the modification effect and improvement of instrument performance. Through this step, it can be finally confirmed whether the modification achieves the expected analysis effect, and ensures that the chromatograph can provide high-quality data support for future sample analysis.

[0095] By implementing the present application, the following benefits are achieved:

[0096] Compared with the prior art, the present application can complete comprehensive detection of 9 kinds of insulating oil characteristic fault gases, including H2(hydrogen), CH4(methane), C2H6(ethane), C2H4(ethylene), C2H2(acetylene), CO(carbon monoxide), CO2(carbon dioxide), O2(oxygen), and N2(nitrogen), in a single sample injection. This one-time detection capability greatly improves detection efficiency, as it reduces the sampling amount of insulating oil and the workload of analysis and detection, thereby reducing time and cost consumption in the detection process. In addition, the gas chromatograph of the present application has high separation efficiency and fast analysis characteristics, and can complete analysis of complex samples in a short time. This means that, compared with existing methods, the present application not only reduces sample usage, but also improves detection sensitivity. This high sensitivity detection capability is crucial for early identification and prevention of potential faults in transformer equipment.

[0097] It can be understood that the above embodiments only express part of the embodiments of the present application, and the description is more specific and detailed, but it cannot be understood as a limitation on the scope of the patent of the present application. It should be noted that, for ordinary skilled persons in the art, the above embodiments or technical features can be freely combined without departing from the concept of the present application, and a number of modifications and improvements can be made, which are all within the protection scope of the present application, i.e. the embodiments described in “in some embodiments” can be freely combined with any of the above embodiments. Therefore, any equivalent transformation and modification within the scope of the claims of the present application shall be covered by the claims of the present application.

Claims

1. A gas chromatograph characterized by, The application relates to a gas component content detection device, which comprises the following components: a first separation module (1) for separating and passing a first batch of measured components in a to-be-detected gas and a second batch of measured components in the to-be-detected gas, and temporarily storing a third batch of measured components in the to-be-detected gas; a second separation module (2) for separating and passing the first batch of measured components in the to-be-detected gas, and temporarily storing the second batch of measured components; a detection module (3) for detecting the component content in the to-be-detected gas; and a reversing valve (4) for switching the content detection of the first batch of measured components, the second batch of measured components and the third batch of measured components, wherein the reversing valve (4) comprises a first valve port (41), a second valve port (42), a third valve port (43), a fourth valve port (44), a fifth valve port (45) and a sixth valve port (46); wherein the outlet end of the first separation module (1) is connected with the first valve port (41), the inlet end of the second separation module (2) is connected with the second valve port (42), the outlet end of the second separation module (2) is connected with the third valve port (43), the fourth valve port (44) is connected with the fifth valve port (45), and the inlet end of the detection module (3) is connected with the sixth valve port (46); the first valve port (41) is communicated with the second valve port (42), the second valve port (42) is communicated with the third valve port (43) through the second separation module (2), the third valve port (43) is communicated with the sixth valve port (46), and when the fourth valve port (44) is communicated with the fifth valve port (45), the first batch of measured components and the second batch of measured components in the to-be-detected gas are separated after passing through the first separation module (1), the first batch of measured components and the second batch of measured components are separated after passing through the first valve port (41), the second valve port (42) and the second separation module (2), the first batch of measured components enters the detection module (3) after passing through the third valve port (43) and the sixth valve port (46), and a detection path for detecting the content of the first batch of measured components in the to-be-detected gas is formed; when the first valve port (41) is communicated with the fourth valve port (44), the second valve port (42) is communicated with the third valve port (43), the fourth valve port (44) is communicated with the fifth valve port (45), and the fifth valve port (45) is communicated with the sixth valve port (46), the third batch of measured components in the to-be-detected gas temporarily stored in the first separation module (1) enters the detection module (3) after passing through the first separation module (1), the first valve port (41), the fourth valve port (44), the fifth valve port (45) and the sixth valve port (46), and a detection path for detecting the content of the third batch of measured components in the to-be-detected gas is formed. ​ ​ ​ ​ ​ ​ ​ The first valve port (41) is in communication with the second valve port (42), the second valve port (42) is in communication with the third valve port (43) through the second separation module (2), the third valve port (43) is in communication with the sixth valve port (46), when the fourth valve port (44) is in communication with the fifth valve port (45), the second batch of measurement components temporarily stored in the second separation module (2) in the to-be-measured gas enters the detection module (3) through the second separation module (2), the third valve port (43) and the sixth valve port (46), forming a detection path for detecting the content of the second batch of measurement components in the to-be-measured gas; The gas chromatograph further comprises: A sample loading module (5) for carrying the to-be-measured gas into the first separation module (1), the outlet end of the sample loading module (5) is connected with the inlet end of the first separation module (1); The first valve port (41) is in communication with the second valve port (42), the second valve port (42) is in communication with the third valve port (43) through the second separation module (2), the third valve port (43) is in communication with the sixth valve port (46), when the fourth valve port (44) is in communication with the fifth valve port (45), the second batch of measurement components temporarily stored in the second separation module (2) in the to-be-measured gas enters the detection module (3) through the second separation module (2), the third valve port (43) and the sixth valve port (46), forming a detection path for detecting the content of the second batch of measurement components in the to-be-measured gas.

2. The gas chromatograph of claim 1, wherein, The sample loading module (5) comprises: A sample gas unit (51) for introducing the to-be-measured gas, the outlet end of the sample gas unit (51) is connected with the inlet end of the first separation module (1); A carrier gas unit (52) for introducing carrier gas to carry the to-be-measured gas, the carrier gas is argon, the outlet end of the carrier gas unit (52) is connected with the inlet end of the first separation module (1).

3. The gas chromatograph of claim 1, wherein, The gas chromatograph further comprises: A damping module (6) for controlling the flow rate of the to-be-measured gas, the inlet end of the damping module (6) is connected with the fourth valve port (44), and the outlet end of the damping module (6) is connected with the fifth valve port (45).

4. The gas chromatograph of claim 1, wherein, The detection module (3) comprises: A first detection unit (31) for detecting the components obtained by separating the to-be-measured gas; A conversion unit (32) for converting the components obtained by separating the to-be-measured gas to obtain the components of the to-be-measured gas after conversion; A second detection unit (33) for detecting the components of the to-be-measured gas after conversion; and A data processing unit (34) for processing the detection data of the first detection unit (31) and the second detection unit (33). The sixth valve port (46) is connected with the inlet end of the first detection unit (31), the outlet end of the first detection unit (31) is connected with the inlet end of the conversion unit (32), and the outlet end of the conversion unit (32) is connected with the inlet end of the second detection unit (33). The data processing unit (34) is in communication connection with the first detection unit (31) and the second detection unit (33).

5. The gas chromatograph according to claim 1, wherein, The first batch of measurement components includes at least one gas of the following chemical formula: H2; The second batch of measurement components includes at least one gas of the following chemical formula: CO, CH4, O2, N2; The third batch of measurement components includes at least one gas of the following chemical formula: CO2, C2H2, C2H4, C2H6.

6. A method of controlling detection of a gas chromatograph according to any one of claims 1 to 5, characterized by, The method comprises the following steps: First batch of measurement component detection: control the first valve port (41) to communicate with the second valve port (42), the second valve port (42) communicates with the third valve port (43) through the second separation module (2), the third valve port (43) communicates with the sixth valve port (46), and the fourth valve port (44) communicates with the fifth valve port (45) to switch to a detection path for detecting the first batch of measurement components in the to-be-detected gas, and detection of the first batch of measurement components in the to-be-detected gas is performed; Third batch of measurement component detection: after the first batch of measurement component detection is completed, the first valve port (41) is controlled to communicate with the fourth valve port (44), the second valve port (42) is controlled to communicate with the third valve port (43), the fourth valve port (44) is controlled to communicate with the fifth valve port (45), and the fifth valve port (45) is controlled to communicate with the sixth valve port (46) to switch to a detection path for detecting the third batch of measurement components in the to-be-detected gas, and detection of the third batch of measurement components in the to-be-detected gas is performed; And, Second batch of measurement component detection: after the third batch of measurement component detection is completed, the first valve port (41) is controlled to communicate with the second valve port (42), the second valve port (42) communicates with the third valve port (43) through the second separation module (2), the third valve port (43) communicates with the sixth valve port (46), and the fourth valve port (44) communicates with the fifth valve port (45) to switch to a detection path for detecting the second batch of measurement components in the to-be-detected gas, and detection of the second batch of measurement components in the to-be-detected gas is performed.

7. The detection control method of a gas chromatograph according to claim 6, characterized by, Before the first batch of measurement component detection, the following step is further included: Gas chromatograph preparation step: self-checking is performed, the first valve port (41) is controlled to communicate with the second valve port (42), the second valve port (42) communicates with the third valve port (43) through the second separation module (2), the third valve port (43) communicates with the sixth valve port (46), and the fourth valve port (44) communicates with the fifth valve port (45) to switch to a preparation path for carrier gas, and the carrier gas is introduced.

Images