Gas insulated equipment monitoring and fault analysis method and apparatus

Abstract

The present application relates to the technical field of electrical equipment state monitoring, and is a kind of gas insulated equipment monitoring and fault analysis method and device, the former is carried out according to the following method: first, before the operation of the gas insulated equipment, inject the required amount of trifluoroiodomethane into the sulfur hexafluoride gas of each gas chamber of the gas insulated equipment;Second, when the gas insulated equipment is running or fault shutdown, the water content and iodine ion content in the sulfur hexafluoride gas of each gas chamber are monitored, and the running state of the gas insulated equipment is evaluated and analyzed according to the water content and iodine ion content in the sulfur hexafluoride gas.The present application avoids the huge difference between the running state and shutdown state detection data of the gas insulated equipment, improves the monitoring accuracy, and monitors the actual running state of the equipment online, providing a reliable evaluation basis for the running state and fault analysis of the gas insulated equipment.

Description

Technical Field

[0001] This invention relates to the field of electrical equipment condition monitoring technology, and is a method and device for monitoring and fault analysis of gas-insulated equipment. Background Technology

[0002] Sulfur hexafluoride (SF6) electrical equipment is widely used due to its small footprint, safe and reliable operation, excellent arc-extinguishing performance, and high insulation strength. During the operation of gas-insulated equipment, the commonly used chemical monitoring methods include moisture content and decomposition product analysis, as other detection methods are difficult to use directly.

[0003] Conventional moisture content testing only provides early warning of some internal equipment faults; it is ineffective for detecting breakdowns or partial discharges in certain components. Decomposition product detection is crucial for fault analysis, but because faults can be caused by a variety of chemical substances, the potential products need to be analyzed using different testing equipment. These devices have vastly different standards and detection accuracies for decomposition products, thus providing only partially valid information.

[0004] During monitoring, some equipment frequently exhibited significant fluctuations in water content and decomposition product concentration between online monitoring and shutdown states. Online monitoring, in particular, showed excessively high water content, even though the equipment itself was functioning normally. This variation is closely related to the production and conversion of hydrogen fluoride, a highly acidic gas that precipitates at high temperatures and neutralizes at low temperatures by reacting with the vessel walls or other substances. In some cases, the water content in the equipment gradually increased, yet the equipment continued to operate normally. When malfunctions occurred, existing water content and decomposition product analyses were insufficient to pinpoint the cause of the fault, necessitating complete disassembly and component-by-component analysis, which consumed considerable time and manpower. Summary of the Invention

[0005] This invention provides a method and apparatus for monitoring and fault analysis of gas-insulated equipment, which overcomes the shortcomings of the prior art and can effectively solve the problems of inaccurate results and inability to analyze the source of faults in existing gas-insulated equipment monitoring methods.

[0006] One of the technical solutions of the present invention is achieved through the following measures: a method for monitoring and fault analysis of gas-insulated equipment, comprising the following steps: The first step is to inject the required amount of trifluoroiodomethane into the sulfur hexafluoride gas in each gas chamber of the gas insulation equipment before operation. The second step is to monitor the water content and iodide ion content in the sulfur hexafluoride gas in each gas chamber during operation or shutdown due to failure, and to evaluate the operating status and analyze the fault based on the water content and iodide ion content of the sulfur hexafluoride gas.

[0007] The following are further optimizations and / or improvements to one of the above-mentioned technical solutions: In the first step described above, the amount of trifluoroiodomethane injected is 10 ppm to 2000 ppm of sulfur hexafluoride in the gas chamber.

[0008] The monitoring of water content and iodide ion content in the above-mentioned sulfur hexafluoride gas is carried out according to the following steps: S1. Connect the absorption tank pre-filled with absorption liquid, iodide ion selective electrode, saturated calomel electrode, and potentiometer, and calibrate the electrode with standard iodide ion solution. S2, use nitrogen to dry the dew point meter and connecting pipeline; S3, connect the air inlet of the dew point meter to the sampling port of the gas insulation equipment, adjust the air inlet flow rate, and connect to the absorption tank and exhaust gas processor; S4, measure the moisture content and record the potentiometer reading every 5 to 15 minutes; S5. When the potentiometer reading changes by more than 5 ppm within 1 to 2 hours, the operating status is predicted and fault analysis is performed based on the iodine ion content and water content values.

[0009] The above-mentioned absorbent is an aqueous solution of sodium hydroxide with a concentration of 0.001 mol / L to 0.1 mol / L.

[0010] Based on the data on moisture content and iodide ion content, the operational status of gas-insulated equipment is assessed and categorized as follows: Type 1: When the water content is ≥300ppm and the iodine ion content is ≤1ppm, it indicates that the gas insulation equipment is fault-free and a small amount of organic matter is released and decomposed. Type 2: When the water content is ≥300ppm and the iodine ion content is ≥5ppm, it indicates that there is partial discharge or breakdown near the epoxy resin material of the gas insulation equipment, and the equipment needs to be shut down for treatment. Type 3: When the moisture content is >300ppm and the iodine ion content is 5ppm > 1ppm, it indicates a malfunction in the gas-insulated equipment, requiring continuous monitoring. If the iodide ion content continues to rise, it indicates that organic matter in the gas-insulated equipment is continuously precipitated and decomposed, and there is partial discharge of epoxy resin-like substances, but no breakdown. If the iodine ion content is stable and no longer rises, and the iodine ion content does not exceed 5 ppm, it indicates that there is a partial discharge in the gas-insulated equipment, but it has stopped, and monitoring needs to be strengthened. Type 4: Moisture content <300ppm and iodine ion content ≥5ppm indicates a fault in the gas insulation equipment, with partial discharge in the silicone rubber or lubricating oil within the system. In this case, the gas insulation equipment needs to be shut down for inspection.

[0011] When the gas-insulated equipment system fails and shuts down, the causes of the failure are analyzed based on the moisture content and iodide ion content data and categorized as follows: When the water content is >300ppm and the iodine ion content is ≥5ppm, the cause of the failure is a fault near the epoxy resin material. When the water content is <300ppm and the iodine ion content is ≥5ppm, the cause of the failure is a fault near silicone rubber materials or materials containing lubricating oil.

[0012] The second technical solution of the present invention is achieved through the following measures: an apparatus for implementing a method for monitoring and analyzing faults in gas-insulated equipment, comprising a dew point meter, an iodide ion meter, and a tail gas processor. The iodide ion meter includes a potentiometer and an absorption tank. A saturated calomel electrode and an iodide ion selective electrode are disposed inside the absorption tank. The saturated calomel electrode and the iodide ion selective electrode are electrically connected to the potentiometer, respectively. A first air inlet line is fixedly connected to the air inlet end of the dew point meter. A quick-connect interface is fixedly provided at the air inlet end of the first air inlet line. A second air inlet line is fixedly connected between the air outlet end of the dew point meter and the air inlet end of the absorption tank. A tail gas line is fixedly connected between the air outlet end of the absorption tank and the air inlet end of the tail gas processor.

[0013] This invention avoids the significant discrepancy between the detection data of gas-insulated equipment in operation and shutdown states, improves monitoring accuracy, monitors the actual operating status of the equipment online, and provides a reliable assessment basis for the operating status and fault analysis of gas-insulated equipment. Attached Figure Description

[0014] Appendix Figure 1 This is a flowchart illustrating Embodiment 7 of the present invention.

[0015] The codes in the attached diagram are as follows: 1 is dew point meter, 2 is absorption tank, 3 is exhaust gas processor, 4 is potentiometer, 5 is saturated calomel electrode, 6 is iodide ion selective electrode, 7 is first intake line, 8 is quick interface, 9 is second intake line, and 10 is exhaust gas line. Detailed Implementation

[0016] This invention is not limited to the following embodiments; specific implementation methods can be determined according to the technical solutions and actual conditions of this invention. Unless otherwise specified, all chemical reagents and chemical products mentioned in this invention are well-known and commonly used chemical reagents and chemical products in the prior art. Unless otherwise specified, the equipment and apparatus used in this invention are all well-known and commonly used equipment and apparatus in the art.

[0017] The present invention will be further described below with reference to embodiments: Example 1: The monitoring and fault analysis method for this gas-insulated equipment is carried out according to the following steps: The first step is to inject the required amount of trifluoroiodomethane into the sulfur hexafluoride gas in each gas chamber of the gas insulation equipment before operation. The second step is to monitor the water content and iodide ion content in the sulfur hexafluoride gas in each gas chamber during operation or shutdown due to failure, and to evaluate the operating status and analyze the fault based on the water content and iodide ion content of the sulfur hexafluoride gas.

[0018] This invention improves the accuracy of fault monitoring in gas-insulated equipment by injecting a marker gas—trifluoroiodomethane—into the sulfur hexafluoride gas. Trifluoroiodomethane itself has excellent insulating properties and can be directly added to the gas-insulated equipment. When fault symptoms appear in the gas-insulated equipment, the impurity gases generated by the fault interact with the trifluoroiodomethane to produce hydrogen iodide gas. Hydrogen iodide is a weak acid and does not readily react with the equipment walls; its concentration varies little between operating and shutdown states. After absorbing the hydrogen iodide gas with an absorbent liquid, the concentration of iodide ions after conversion and decomposition is used instead of the fluoride ion concentration used in conventional monitoring as the indicator for gas-insulated equipment monitoring. This invention can effectively predict and analyze faults, avoiding significant variations in monitoring indicators at different temperatures, and improving fault prediction and analysis capabilities.

[0019] Example 2: As an optimization of the above example, in the first step, the amount of trifluoroiodomethane injected is 10 ppm to 2000 ppm of sulfur hexafluoride in the gas chamber.

[0020] Example 3: As an optimization of the above examples, as shown in the appendix Figure 1 As shown, the monitoring of water content and iodide ion content in sulfur hexafluoride gas is carried out according to the following steps: S1. Connect the absorption tank 2 pre-filled with absorption liquid, the iodide ion selective electrode 6, the saturated calomel electrode 5, and the potentiometer 4. Calibrate the electrodes with a standard iodide ion solution. S2, use nitrogen to dry the dew point meter 1 and its connecting pipes; S3, connect the air inlet of the dew point meter 1 to the sampling port of the gas insulation equipment, adjust the air inlet flow rate (the flow rate can be adjusted by adjusting the needle valve of the sampling port or by adjusting the data displayed on the dew point meter 1), and connect it to the absorption tank 2 and the exhaust gas processor 3. S4, measure the moisture content and record the potentiometer reading every 5 to 15 minutes; S5. When the potentiometer reading changes by more than 5 ppm within 1 to 2 hours, the operating status is predicted and fault analysis is performed based on the iodine ion content and water content values.

[0021] Example 4: As an optimization of the above example, the collected solution is an aqueous solution of sodium hydroxide with a concentration of 0.001 mol / L to 0.1 mol / L.

[0022] Example 5: As an optimization of the above examples, the operating status of gas-insulated equipment is evaluated based on moisture content and iodide ion content data, and is categorized into the following types: Type 1: When the moisture content is ≥300ppm and the iodide ion content is ≤1ppm, it indicates that the gas-insulated equipment is fault-free, with a small amount of organic matter precipitating and decomposing. It is recommended to continue observation in this case; if the data stabilizes, work can continue.

[0023] Type 2: When the water content is ≥300ppm and the iodine ion content is ≥5ppm, it indicates that there is partial discharge or breakdown near the epoxy resin material of the gas insulation equipment, and the equipment needs to be shut down for treatment.

[0024] Type 3: When the moisture content is >300ppm and the iodine ion content is 5ppm > 1ppm, it indicates a malfunction in the gas-insulated equipment, requiring continuous monitoring. If the iodide ion content continues to rise, it indicates that organic matter in the gas-insulated equipment is continuously precipitated and decomposed, and there is partial discharge of epoxy resin-like substances, but no breakdown. If the iodine ion content is stable and no longer rises, and the iodine ion content does not exceed 5 ppm, it indicates that there is a partial discharge in the gas-insulated equipment, but it has stopped, and monitoring needs to be strengthened; at this time, the gas-insulated equipment can continue to operate.

[0025] Type 4: Moisture content <300ppm and iodine ion content ≥5ppm indicates a fault in the gas insulation equipment, with partial discharge in the silicone rubber or lubricating oil within the system. In this case, the gas insulation equipment needs to be shut down for inspection.

[0026] Example 6: As an optimization of the above examples, when the gas-insulated equipment system fails and shuts down, the causes of the gas-insulated equipment failure are analyzed and classified into the following types based on the moisture content and iodide ion content data: When the water content is >300ppm and the iodine ion content is ≥5ppm, the cause of the failure is a fault near the epoxy resin material. When the water content is <300ppm and the iodine ion content is ≥5ppm, the cause of the failure is a fault near silicone rubber materials or materials containing lubricating oil.

[0027] When a gas-insulated equipment system fails and shuts down, the source of the fault can be analyzed based on the two types mentioned above, and maintenance can be carried out on the part of the fault source without disassembling the entire equipment, which can save a lot of time and manpower.

[0028] Example 7: As Figure 1As shown, the apparatus for implementing gas insulation equipment monitoring and fault analysis includes a dew point meter 1, an iodide ion analyzer, and a tail gas processor 3. The iodide ion analyzer includes a potentiometer 4 and an absorption tank 2. The absorption tank 2 is equipped with a saturated calomel electrode 5 and an iodide ion selective electrode 6. The saturated calomel electrode 5 and the iodide ion selective electrode 6 are electrically connected to the potentiometer. The inlet end of the dew point meter 1 is fixedly connected to a first inlet pipeline 7. The inlet end of the first inlet pipeline 7 is fixedly equipped with a quick interface 8. The outlet end of the dew point meter 1 is fixedly connected to the inlet end of the absorption tank 2, and the outlet end of the absorption tank 2 is fixedly connected to the inlet end of the tail gas processor 3, and the tail gas pipeline 10 is fixedly connected to the outlet end of the absorption tank 2.

[0029] In this invention, the moisture content is measured using a dew point meter, and the iodide ion content is measured using an iodide ion analyzer. When using the device, the quick-connect interface 8 is connected to the sampling port of the gas-insulated equipment, and sampling and data reading are performed according to the operating steps of Example 5. This invention is suitable for routine maintenance, monitoring, and testing of various sulfur hexafluoride gas-insulated equipment. During operation, there is no need to change the testing cycle; simply replace the existing moisture measurement experiment with the method of this invention.

[0030] In summary, this invention provides a method for monitoring and analyzing faults in gas-insulated equipment. This method involves injecting trifluoroiodomethane to monitor the hydrogen iodide content and then analyzing the changes in water content and iodide ion content to perform fault monitoring and analysis. This significantly avoids the problem of large discrepancies between the monitoring data of gas-insulated equipment in its operating and shutdown states, thereby improving monitoring accuracy and providing a reliable basis for evaluating the actual operating status and fault analysis of gas-insulated equipment.

[0031] The above technical features constitute the embodiments of the present invention, which have strong adaptability and implementation effect. Unnecessary technical features can be added or removed according to actual needs to meet the needs of different situations.

Claims

1. A method of gas insulated equipment monitoring and fault analysis, characterized in that The following steps should be followed: First, before the gas insulation equipment is put into operation, inject the required amount of trifluoroiodomethane into the sulfur hexafluoride gas in each gas chamber of the gas insulation equipment; Second, when the gas insulation equipment is in operation or shut down due to a fault, monitor the water content and iodide ion content in the sulfur hexafluoride gas in each gas chamber, and evaluate the operating status of the gas insulation equipment and analyze the fault based on the water content and iodide ion content in the sulfur hexafluoride gas. Based on moisture content and iodide ion content data, the operating status of gas-insulated equipment is assessed and categorized as follows: Type 1: When the water content is ≥300ppm and the iodine ion content is ≤1ppm, it indicates that the gas insulation equipment is fault-free and a small amount of organic matter is released and decomposed. Type 2: When the water content is ≥300ppm and the iodine ion content is ≥5ppm, it indicates that there is partial discharge or breakdown near the epoxy resin material of the gas insulation equipment, and the equipment needs to be shut down for treatment. Type 3: When the moisture content is >300ppm and the iodine ion content is 5ppm > 1ppm, it indicates a malfunction in the gas-insulated equipment, requiring continuous monitoring. If the iodide ion content continues to rise, it indicates that organic matter in the gas-insulated equipment is continuously precipitated and decomposed, and there is partial discharge of epoxy resin-like substances, but no breakdown. If the iodine ion content is stable and no longer rises, and the iodine ion content does not exceed 5 ppm, it indicates that there is a partial discharge in the gas-insulated equipment, but it has stopped, and monitoring needs to be strengthened. Type 4: Moisture content <300ppm and iodine ion content ≥5ppm indicates a fault in the gas insulation equipment, with partial discharge in the silicone rubber or lubricating oil within the system. In this case, the gas insulation equipment needs to be shut down for inspection.

2. The gas insulated apparatus monitoring and fault analysis method according to claim 1, characterized by In the first step, the amount of trifluoroiodomethane injected is 10 ppm to 2000 ppm of sulfur hexafluoride in the gas chamber.

3. The gas insulated apparatus monitoring and fault analysis method according to claim 1 or 2, characterized by The monitoring of water content and iodide ion content in sulfur hexafluoride gas is carried out according to the following steps: S1 connects to the absorption tank pre-filled with absorption liquid, iodide ion selective electrode, saturated calomel electrode, and potentiometer, and calibrates the electrode with standard iodide ion solution; S2, use nitrogen to dry the dew point meter and connecting pipeline; S3, connect the air inlet of the dew point meter to the sampling port of the gas insulation equipment, adjust the air inlet flow rate, and connect to the absorption tank and exhaust gas processor; S4, measure the moisture content and record the potentiometer reading every 5 to 15 minutes; S5. When the potentiometer reading changes by more than 5 ppm within 0.5 h to 2 h, the operating status is predicted and fault analysis is performed based on the iodine ion content and water content values.

4. The gas insulated apparatus monitoring and fault analysis method according to claim 3, characterized by The absorbent is an aqueous solution of sodium hydroxide with a concentration of 0.001 mol / L to 0.1 mol / L.

5. The gas insulated apparatus monitoring and fault analysis method according to claim 1 or 2, characterized by When a gas-insulated equipment system malfunctions and shuts down, the causes of the malfunction are analyzed based on data on moisture content and iodide ion content, and are categorized as follows: When the water content is >300ppm and the iodine ion content is ≥5ppm, the cause of the failure is a fault near the epoxy resin material. When the water content is <300ppm and the iodine ion content is ≥5ppm, the cause of the failure is a fault near silicone rubber materials or materials containing lubricating oil.

6. An apparatus for implementing the gas insulated device monitoring and fault analysis method according to any one of claims 1 to 5, characterized by The device includes a dew point meter, an iodide ion analyzer, and an exhaust gas processor. The iodide ion analyzer includes a potentiometer and an absorption tank. The absorption tank is equipped with a saturated calomel electrode and an iodide ion selective electrode, which are electrically connected to the potentiometer. The dew point meter is fixedly connected to a first air inlet line, and the first air inlet line is fixedly equipped with a quick-connect interface. The dew point meter is fixedly connected to the absorption tank's air inlet by a second air inlet line, and the absorption tank's air outlet is fixedly connected to the exhaust gas processor's air inlet by an exhaust gas line.

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