Verification system and oil injection method for on-line transformer monitoring device
By designing a calibration system for the transformer online monitoring device and adopting independent valve control and concentration sequence injection methods, the problem of automated calibration of the transformer online monitoring device was solved, realizing an efficient and pollution-free detection process, and ensuring detection accuracy and oil safety.
Patent Information
- Application Number
- CN202511192251.9
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-08-25
- Publication Date
- 2025-11-21
AI Technical Summary
Existing technologies lack automated calibration devices for online transformer monitoring equipment, resulting in high costs for manual calibration and the risk of cross-contamination of oil, which affects the accuracy of detection.
A calibration system for an online transformer monitoring device was designed. The system controls each oil cylinder pipeline with independent valves to achieve automated oil injection and cyclic calibration. Low, medium and high concentration oil cylinders and corresponding test inlets and loops are used to ensure that the oil concentration is injected sequentially into the parallel point design to avoid backflow and form a closed-loop protection.
It achieves automated verification, frees up manual labor, improves verification efficiency, ensures "zero pollution" in the testing process, and guarantees the accuracy of testing and the safety and stability of the main transformer oil.
Smart Images
Figure CN120992797A_ABST
Abstract
Description
Technical Field
[0001] This application relates to the field of transformer chromatography calibration technology, specifically to a calibration system for an online transformer monitoring device. Background Technology
[0002] The main transformer determines whether a fault has occurred by monitoring changes in the composition of dissolved gases in its internal oil. For example, when a transformer overheats at a low temperature, the content of methane and hydrogen will increase significantly. The main transformer uses online monitoring devices to monitor the dissolved gases in the oil, determine changes in their composition and content, and thus assess the transformer's operating status.
[0003] Taking Dongying City as an example, the city has 51 220kV main transformers distributed across various substations, and each 220kV main transformer is required to upload data every 12 hours. Traditional manual verification involves opening valves on-site for inspection, and the detection time for each concentration is about 4 hours, resulting in high labor costs.
[0004] Based on the above, in the process of frequent daily calibration, the accuracy of monitoring dissolved gases in the main transformer oil is directly determined by the online monitoring device. However, the existing technology lacks an automated calibration device for the online monitoring device. Summary of the Invention
[0005] Firstly, this application provides a calibration system for an online transformer monitoring device, which achieves automated oil injection and cyclic calibration in a pollution-free environment.
[0006] The technical solution of this application is as follows: A calibration system for an online transformer monitoring device is disclosed. The calibration system is connected to the monitoring pipeline of the main transformer online monitoring device. The monitoring pipeline includes the online monitoring device and a main transformer oil outlet pipeline and a main transformer oil return pipeline connected to the online monitoring device via an oil inlet and an oil return outlet, respectively. The calibration system includes a low-concentration oil cylinder, a medium-concentration oil cylinder, a high-concentration oil cylinder, and a first inspection path, a second inspection path, and a third inspection path, respectively matched with each oil cylinder. The first, second, and third inspection paths are connected in parallel and then lead to the oil inlet. The calibration system also includes components matched with each oil cylinder. The system includes a first inspection circuit, a second inspection circuit, and a third inspection circuit; the first inspection circuit, the second inspection circuit, and the third inspection circuit are connected in parallel at a parallel connection point and then connected to the return oil port; the first inspection circuit, the second inspection circuit, and the third inspection circuit are provided with a common oil drain pipe, the end of which is connected to a waste oil drum; the ends of the first inspection inlet, the second inspection inlet, the third inspection inlet, the first inspection circuit, the second inspection circuit, the third inspection circuit, and the oil drain pipe are respectively provided with a first oil inlet valve, a second oil inlet valve, a third oil inlet valve, a first return oil valve, a second return oil valve, a third return oil valve, and an oil drain valve.
[0007] Furthermore, the main transformer oil outlet pipeline and the main transformer oil return pipeline are respectively equipped with a main transformer oil inlet valve and a main transformer oil return valve.
[0008] The standard oil concentrations for the low-concentration oil cylinder, the medium-concentration oil cylinder, and the high-concentration oil cylinder can be determined according to Q / GDW 10536-2021 - "Technical Specification for Online Monitoring Device of Dissolved Gases in Transformer Oil".
[0009] Furthermore, the parallel connection point of the first inspection circuit, the second inspection circuit, and the third inspection circuit is located between the first return oil valve and the second return oil valve.
[0010] Furthermore, the parallel connection point of the first inspection circuit, the second inspection circuit, and the third inspection circuit is located between the first return oil valve and the second return oil valve.
[0011] Furthermore, the front end of the oil drain line is located between the third return oil valve and the oil drain valve.
[0012] Secondly, this application also provides an oil injection method for injecting oil into the oil injection pipeline of an online chromatographic monitoring device for transformers, comprising the following steps: S1. Open the first oil inlet valve and oil outlet valve to flush the pipeline with low-concentration oil for 10 minutes. S2. Close the drain valve and open the first return valve to allow the low-concentration oil to circulate in the calibration system. After the online monitoring device uploads the test data, close the first return valve and open the drain valve to flush the low-concentration oil through the pipeline for 5 minutes. S3. Repeat step S2; S4. Close the drain valve and open the first return valve to allow the low-concentration oil to circulate in the calibration system. After the online monitoring device uploads the test data, close the first inlet valve and the first return valve, and open the second inlet valve and the drain valve to allow the medium-concentration oil to flush through the pipeline for 10 minutes. S5. Close the drain valve and open the second return valve to circulate the medium-concentration oil in the calibration system. After the online monitoring device uploads the test data, close the second return valve and open the drain valve to flush the medium-concentration oil through the pipeline for 5 minutes. S6. Repeat step S5; S7. Close the drain valve and open the second return valve to allow the medium-concentration oil to circulate in the calibration system. After the online monitoring device uploads the test data, close the second inlet valve and the second return valve, and open the third inlet valve and the drain valve to allow the high-concentration oil to flush through the pipeline for 10 minutes. S8. Close the drain valve and open the third return valve to allow the high-concentration oil to circulate in the calibration system. After the online monitoring device uploads the test data, close the third return valve and open the drain valve to flush the high-concentration oil through the pipeline for 5 minutes. S9. Repeat step S8; S10. Close the drain valve and open the third return valve to circulate the high-concentration oil in the calibration system. After the online monitoring device uploads the test data, close the third inlet valve and the third return valve, and open the main transformer inlet valve and the drain valve to flush the oil in the main transformer through the pipeline for 10 minutes. Then close all valves. The 10-minute flushing is necessary because the main transformer contains tens of tons of oil; flushing will not affect the transformer's performance.
[0013] Due to the adoption of the above technical solution, the beneficial effects of this application are as follows: 1. This application automates the standard oil calibration process. Conventional calibration relies on manual judgment of flushing time. In this application, each cylinder pipeline is controlled by an independent valve, enabling precise valve control, freeing up manual labor, and improving calibration efficiency.
[0014] 2. This application achieves "zero pollution" in the calibration process. Whether it's the main transformer oil or the standard oil, once it enters the online monitoring device and completes the test, it will become waste oil due to changes in properties and needs to be flushed out; this is unavoidable. The oil after calibration is called waste oil because the testing process requires operations such as adding gas, shaking, and taking gas. After these operations, the oil will be different from the original oil (e.g., the monitoring gas is lacking), and thus naturally becomes "contaminated" or "interfering." Therefore, whether it's the main transformer oil or the standard oil, when flushing out the waste oil in the pipeline, they will come into contact with each other, inevitably mixing and causing cross-contamination of the oil.
[0015] It should be noted that the main transformer oil can reach tens of tons, and contamination would result in enormous costs. Furthermore, contamination of different standard oils can lead to inaccurate test data, thereby compromising the reliability of the calibration results. In this application, each concentration of oil is tested three times to improve accuracy and avoid exceptional values. Before the first test, the pipeline is flushed with the corresponding concentration of standard oil to prevent contamination. After the data from the third test is uploaded, the pipeline is flushed with the next concentration of standard oil to shorten flushing time. Especially during the final flush, this application uses main transformer oil for flushing, preventing high-concentration oil from contaminating the main transformer oil during subsequent tests. This application forms a closed-loop protection process, ultimately achieving "zero contamination" in the calibration process and ensuring the safety and stability of the main transformer oil.
[0016] 3. In this application, the parallel connection points of the testing circuits have undergone special design. Specifically, the parallel connection points of the three testing circuits are not arbitrarily chosen; they should be located between the first and second return oil valves, or before the first return oil valve. This is because the standard oil injection follows a strict sequence from low to high concentration. This sequence avoids backflow in the calibration circuit, preventing cross-contamination of the oil and ensuring the accuracy of the test. A small amount of residue in low-concentration oil has little impact on the subsequent test results of high-concentration oil; however, residue in high-concentration oil will severely interfere with the subsequent test of low-concentration oil, leading to data deviation. For example, if the high-concentration oil has a high acetylene content and residue, it will directly affect the accuracy of acetylene detection in low-concentration oil, while the impact of low-concentration residue on high-concentration detection is negligible.
[0017] If the parallel connection point is improperly set and backflow occurs, it will directly disrupt the above concentration injection sequence, causing confusion between oils of different concentrations. For example, if the parallel connection point is set between the second and third return valves, the low-concentration oil will be suddenly cut off during circulation. This will result in low-concentration oil residue between the parallel connection point and the second return valve. This residue will not be washed away by the subsequent flushing process. During medium-concentration circulation, it will enter the medium-concentration oil cylinder to dilute the oil, causing cross-contamination and affecting the accuracy of the test. Attached Figure Description
[0018] The accompanying drawings, which are provided to further illustrate this application and form part of this application, illustrate exemplary embodiments of this application and are used to explain this application, but do not constitute an undue limitation of this application.
[0019] Figure 1 This is a schematic diagram of a calibration system for an online transformer monitoring device provided in this application.
[0020] In the attached diagram: 1. Oil inlet; 2. Oil return outlet; 3. Main transformer oil outlet line; 3-1. Main transformer oil inlet valve; 4. Main transformer oil return line; 4-1. Main transformer oil return valve; 5. Low concentration oil cylinder; 5-1. First inspection inlet; 5-2. First inspection circuit; 5-3. First oil inlet valve; 5-4. First oil return valve; 6. Medium concentration oil cylinder; 6-1. Second inspection inlet; 6-2. Second inspection circuit; 6-3. Second oil inlet valve; 6-4. Second oil return valve; 7. High concentration oil cylinder; 7-1. Third inspection inlet; 7-2. Third inspection circuit; 7-3. Third oil inlet valve; 7-4. Third oil return valve; 8. Oil drain line; 8-1. Oil drain valve; 9. Waste oil drum. Detailed Implementation
[0021] Based on the background technology described, as shown in the appendix Figure 1As shown, this application provides a verification system for an online transformer monitoring device. The verification system is implemented by connecting the oil injection pipeline to the main transformer, and the verification system is implemented by connecting the monitoring pipeline of the online transformer monitoring device. The monitoring pipeline includes the online monitoring device and a main transformer oil outlet pipeline 3 and a main transformer oil return pipeline 4, which are respectively connected to the online monitoring device through an oil inlet 1 and an oil return outlet 2. The verification system includes a low-concentration oil cylinder 5, a medium-concentration oil cylinder 6, a high-concentration oil cylinder 7, and a first inspection path 5-1, a second inspection path 6-1, and a third inspection path 7-1, respectively, matched with each oil cylinder. The first inspection path 5-1, the second inspection path 6-1, and the third inspection path 7-1 are connected in parallel and then connected to the oil inlet 1. The verification system also includes a first inspection path matched with each oil cylinder. The system includes a first inspection circuit 5-2, a second inspection circuit 6-2, and a third inspection circuit 7-2. The first inspection circuit 5-2, the second inspection circuit 6-2, and the third inspection circuit 7-2 are connected in parallel at a parallel point and then connected to the return oil port 2. The first inspection circuit 5-2, the second inspection circuit 6-2, and the third inspection circuit 7-2 are provided with a common drain pipe 8, the end of which is connected to a waste oil tank 9. The ends of the first inspection inlet 5-1, the second inspection inlet 6-1, the third inspection inlet 7-1, the first inspection circuit 5-2, the second inspection circuit 6-2, the third inspection circuit 7-2, and the drain pipe 8 are respectively equipped with a first inlet valve 5-3, a second inlet valve 6-3, a third inlet valve 7-3, a first return oil valve 5-4, a second return oil valve 6-4, a third return oil valve 7-4, and a drain valve 8-1.
[0022] The main transformer oil outlet pipeline 3 and the main transformer oil return pipeline 4 are respectively equipped with a main transformer oil inlet valve 3-1 and a main transformer oil return valve 4-1.
[0023] In the above technical solution, conventional calibration relies on manual judgment of flushing time. By controlling each cylinder pipeline with independent valves, precise valve control can be achieved, freeing up manual labor and improving calibration efficiency.
[0024] In a preferred embodiment of this application, the standard oil cylinders for each concentration are detachable cylinders. This improves calibration flexibility and allows for multiple uses, saving costs. This application also provides an oil injection method for injecting oil into the oil injection pipeline of an online chromatographic monitoring device for transformers, comprising the following steps: S1. Open the first oil inlet valve and oil outlet valve to flush the pipeline with low-concentration oil for 10 minutes. S2. Close the drain valve and open the first return valve to allow the low-concentration oil to circulate in the calibration system. After the online monitoring device uploads the test data, close the first return valve and open the drain valve to flush the low-concentration oil through the pipeline for 5 minutes. S3. Repeat step S2; S4. Close the drain valve and open the first return valve to allow the low-concentration oil to circulate in the calibration system. After the online monitoring device uploads the test data, close the first inlet valve and the first return valve, and open the second inlet valve and the drain valve to allow the medium-concentration oil to flush through the pipeline for 10 minutes. S5. Close the drain valve and open the second return valve to circulate the medium-concentration oil in the calibration system. After the online monitoring device uploads the test data, close the second return valve and open the drain valve to flush the medium-concentration oil through the pipeline for 5 minutes. S6. Repeat step S5; S7. Close the drain valve and open the second return valve to allow the medium-concentration oil to circulate in the calibration system. After the online monitoring device uploads the test data, close the second inlet valve and the second return valve, and open the third inlet valve and the drain valve to allow the high-concentration oil to flush through the pipeline for 10 minutes. S8. Close the drain valve and open the third return valve to allow the high-concentration oil to circulate in the calibration system. After the online monitoring device uploads the test data, close the third return valve and open the drain valve to flush the high-concentration oil through the pipeline for 5 minutes. S9. Repeat step S8; S10. Close the drain valve and open the third return valve to allow the high-concentration oil to circulate in the calibration system. After the online monitoring device uploads the test data, close the third inlet valve and the third return valve, and open the main transformer inlet valve and the drain valve to flush the oil in the main transformer through the pipeline. After 5 minutes, close all valves.
[0025] In practical implementation, each online monitoring device is equipped with a separate oil injection control system, which includes an MCU and a 4G communication module. The MCU sends switching commands to each valve according to the logical sequence of the oil injection steps, controlling the flow of different standard oils. In practice, the oil injection control system obtains the verification progress of the online monitoring device by reading its status code. For example, in this embodiment, the Shanghai Siyuan TROM-600 online monitoring device is used. 0x0000 indicates initial standby; 0x0001 indicates device self-test; 0x0004 indicates oil circulation; 0x0008 indicates oil inlet; 0x0010 indicates degassing; 0x0020 indicates sampling; 0x0080 indicates device cleaning; and 0x0100 indicates oil change. Based on the above, when the oil injection control system reads the status code of the online monitoring device, it transmits it to the MCU, which then controls the valve opening and closing. In this embodiment, the MCU reads the status code of the online monitoring device through a 485 communication port.
[0026] Based on the above, this application achieves "zero pollution" in the verification process. Whether it's the main transformer oil or the standard oil, once it enters the online monitoring device and completes the test, it will become waste oil due to changes in properties and needs to be flushed out; this is unavoidable. The oil after verification is called waste oil because the testing process requires operations such as adding gas, shaking, and taking gas. After these operations, the oil will be different from the original oil (e.g., the monitoring gas is lacking), thus naturally becoming "contaminated" or "interfering." Therefore, whether it's the main transformer oil or the standard oil, when flushing out the waste oil in the pipeline, they will come into contact with each other, inevitably mixing and causing cross-contamination. It should be noted that the main transformer oil can reach tens of tons; once contaminated, it will cause huge cost losses. Furthermore, if different standard oils are contaminated, it will lead to inaccurate test data, thus making the verification results unreliable. In this application, each concentration of oil is tested three times to improve detection accuracy and avoid outliers. Before the first test, the pipeline is flushed with standard oil of the corresponding concentration to avoid contamination. After the data results from the third test are uploaded, the pipeline is flushed with standard oil of the next lower concentration to shorten the flushing time. Especially during the final flush, this application uses the transformer's own oil for flushing, which can prevent high-concentration oil from contaminating the transformer's oil during the next test. This application forms a closed-loop protection process, ultimately achieving "zero contamination" in the verification process and ensuring the safety and stability of the transformer's oil.
[0027] In a preferred embodiment of this application, the front end of the oil drain line is located between the third return oil valve and the drain valve. The low-concentration oil cylinder, medium-concentration oil cylinder, and high-concentration oil cylinder are detachable cylinders. In this application, the parallel connection point of the test circuit has been specially designed. Specifically, the parallel connection point of the three test circuits is not arbitrary; the parallel connection point should be between the first return oil valve and the second return oil valve, or before the first return oil valve, because the standard oil injection has a strict order from low concentration to high concentration. This order can avoid backflow in the calibration circuit, prevent cross-contamination of oil, and is crucial for ensuring the accuracy of the test. If there is a small amount of residue in the low-concentration oil, it will have little impact on the test results of the subsequent high-concentration oil; however, if there is residue in the high-concentration oil, it will seriously interfere with the test of the subsequent low-concentration oil, leading to data deviation. For example, if the acetylene content in the high-concentration oil is high and there is residue, it will directly affect the accuracy of the acetylene test in the low-concentration oil, while the impact of the low-concentration residue on the high-concentration test is negligible. If the parallel connection point is improperly set and backflow occurs, it will directly disrupt the above concentration injection sequence, causing confusion between oils of different concentrations. For example, if the parallel connection point is set between the second and third return valves, the low-concentration oil will be suddenly cut off during circulation. This will result in low-concentration oil residue between the parallel connection point and the second return valve. This residue will not be washed away by the subsequent flushing process. During medium-concentration circulation, it will enter the medium-concentration oil cylinder to dilute the oil, causing cross-contamination and affecting the accuracy of the test.
[0028] Similarly, the connection point of the drain line should also be designed outside the three test circuits, and not before the parallel connection point of the test circuits.
[0029] Any aspects not described in this application can be implemented using or by referencing existing technologies. The above descriptions are merely embodiments of this application and are not intended to limit the scope of this application. For those skilled in the art, this application can have… Various modifications and variations. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application shall be included within the scope of the claims of this application.
Claims
1. A calibration system for an online transformer monitoring device, wherein the calibration system is connected to the monitoring pipeline of the online monitoring device of the main transformer, the monitoring pipeline including the online monitoring device and a main transformer oil outlet pipeline and a main transformer oil return pipeline respectively connected to the online monitoring device through an oil inlet and an oil return outlet, characterized in that, The calibration system includes a low-concentration oil cylinder, a medium-concentration oil cylinder, a high-concentration oil cylinder, and a first inspection path, a second inspection path, and a third inspection path respectively matched with each oil cylinder; the first inspection path, the second inspection path, and the third inspection path are connected in parallel and then connected to the oil inlet; The calibration system also includes a first inspection circuit, a second inspection circuit, and a third inspection circuit, each matched with a hydraulic cylinder; the first inspection circuit, the second inspection circuit, and the third inspection circuit are connected in parallel at a parallel connection point and then connected to the oil return port; the first inspection circuit, the second inspection circuit, and the third inspection circuit are provided with a common oil drain pipe, and the end of the oil drain pipe is connected to a waste oil drum; The first inspection inlet, the second inspection inlet, the third inspection inlet, the first inspection circuit, the second inspection circuit, the third inspection circuit, and the oil drain line are respectively equipped with a first oil inlet valve, a second oil inlet valve, a third oil inlet valve, a first oil return valve, a second oil return valve, a third oil return valve, and an oil drain valve at the end.
2. The calibration system for an online transformer monitoring device according to claim 1, characterized in that, The main transformer oil outlet pipeline and the main transformer oil return pipeline are respectively equipped with a main transformer oil inlet valve and a main transformer oil return valve.
3. The calibration system for an online transformer monitoring device according to claim 2, characterized in that, The low-concentration, medium-concentration, and high-concentration oil cylinders are detachable constant-pressure oil cylinders.
4. The calibration system for an online transformer monitoring device according to claim 3, characterized in that, The parallel connection point of the first inspection circuit, the second inspection circuit, and the third inspection circuit is located between the first return oil valve and the second return oil valve.
5. The calibration system for an online transformer monitoring device according to claim 4, characterized in that, The front end of the oil drain line is located between the third return oil valve and the oil drain valve.
6. An oil injection method for injecting oil into the oil injection pipeline of the online chromatographic monitoring device for transformers as described in claim 5, characterized in that, Includes the following steps: S1. Open the first oil inlet valve and oil outlet valve to flush the pipeline with low-concentration oil for 10 minutes. S2. Close the drain valve and open the first return valve to allow the low-concentration oil to circulate in the calibration system. After the online monitoring device uploads the test data, close the first return valve and open the drain valve to flush the low-concentration oil through the pipeline for 5 minutes. S3. Repeat step S2; S4. Close the drain valve and open the first return valve to allow the low-concentration oil to circulate in the calibration system. After the online monitoring device uploads the test data, close the first inlet valve and the first return valve, and open the second inlet valve and the drain valve to allow the medium-concentration oil to flush through the pipeline for 10 minutes. S5. Close the drain valve and open the second return valve to circulate the medium-concentration oil in the calibration system. After the online monitoring device uploads the test data, close the second return valve and open the drain valve to flush the medium-concentration oil through the pipeline for 5 minutes. S6. Repeat step S5; S7. Close the drain valve and open the second return valve to allow the medium-concentration oil to circulate in the calibration system. After the online monitoring device uploads the test data, close the second inlet valve and the second return valve, and open the third inlet valve and the drain valve to allow the high-concentration oil to flush through the pipeline for 10 minutes. S8. Close the drain valve and open the third return valve to allow the high-concentration oil to circulate in the calibration system. After the online monitoring device uploads the test data, close the third return valve and open the drain valve to flush the high-concentration oil through the pipeline for 5 minutes. S9. Repeat step S8; S10. Close the drain valve and open the third return valve to allow the high-concentration oil to circulate in the calibration system. After the online monitoring device uploads the test data, close the third inlet valve and the third return valve, and open the main transformer inlet valve and the drain valve to flush the oil in the main transformer through the pipeline. After 10 minutes, close all valves.