Transformer station thermometer automatic calibration device

Abstract

The utility model relates to the field of thermometer calibration, in particular to an automatic calibration device for a transformer substation thermometer, which improves the efficiency and accuracy of thermometer calibration. The utility model provides an automatic calibration device for a transformer station thermometer, which comprises a control module, an image acquisition module, a data transmission module, an image identification module, a man-machine interaction module and a power supply module, and is characterized in that the control module is used for controlling the image acquisition module to acquire image data of a thermometer dial and a thermostatic bath display interface; the data transmission module is used for sending the image data to the image recognition module to extract temperature display values of a thermometer dial and a transformer substation thermostatic bath display interface and sending the extracted temperature display values to the man-machine interaction module, the man-machine interaction module is used for verifying the temperature display values, and the power supply module supplies power to all the modules. The utility model is suitable for automatic calibration of the transformer station thermometer.

Description

Technical Field

[0001] This utility model relates to the field of thermometer calibration, specifically to an automatic calibration device for substation thermometers. Background Technology

[0002] Currently, substation thermometer calibration is conducted on-site. This involves placing the thermometer sensor in a constant-temperature bath, waiting for the bath temperature to rise to a specific level and stabilize, then reading the values ​​of the bath and the thermometer under test to calibrate the readings. A multimeter is then used to test the continuity of the thermometer's alarm terminals. However, this method has several drawbacks: First, this work requires at least three people working continuously, which is labor-intensive. Second, it requires frequent parameter settings for the constant-temperature bath, and the workers are constantly at height, posing significant safety hazards. Third, ground personnel need to constantly record thermometer readings and test the continuity of temperature alarm terminals, which is affected by the cross-operation of other work groups, resulting in significant time consumption and low calibration efficiency. Utility Model Content

[0003] The purpose of this invention is to overcome the shortcomings of the prior art and provide an automatic calibration device for substation thermometers, which improves the efficiency and accuracy of thermometer calibration.

[0004] This utility model achieves the above objectives by adopting the following technical solution: This utility model provides an automatic calibration device for substation thermometers, including a control module, an image acquisition module, a data transmission module, an image recognition module, a human-machine interaction module, and a power supply module. The control module controls the image acquisition module to acquire image data from the thermometer dial and the constant temperature bath display interface. The data transmission module sends the image data to the image recognition module to extract the temperature display values ​​from the thermometer dial and the substation constant temperature bath display interface, and then sends the extracted temperature display values ​​to the human-machine interaction module. The human-machine interaction module is used to calibrate the temperature display values. The power supply module provides power to each module.

[0005] Furthermore, the control module adopts a PLC S7-200SMAR.

[0006] Furthermore, the image acquisition module uses a QOER button-type dual-screen action camera, whose controller is connected to a PLC.

[0007] Furthermore, the automatic thermometer calibration device also includes a retractable camera bracket, the maximum extension of which corresponds to the height of the thermometer dial.

[0008] Furthermore, the human-computer interaction module uses a TK8072iP touchscreen.

[0009] The beneficial effects of this utility model are:

[0010] This invention uses a control module to control an image acquisition module to acquire image data from the thermometer dial and the constant temperature bath display interface. This data is then sent to an image recognition module to extract the temperature display values ​​from both interfaces. The extracted values ​​are then sent to a human-machine interface module for automatic temperature verification. This improves the efficiency and accuracy of thermometer verification, reduces human interference with test data, avoids cross-operation with other work groups during verification, and increases maintenance efficiency. It also reduces workload, lowers labor costs, significantly reduces safety risks associated with prolonged work at heights, and enhances maintenance safety and efficiency. Attached Figure Description

[0011] Figure 1 This is a structural block diagram of an automatic calibration device for a substation thermometer provided in an embodiment of this utility model;

[0012] Figure 2 This is a schematic diagram of a retractable camera bracket structure provided in an embodiment of this utility model. Detailed Implementation

[0013] To make the objectives, technical solutions, and advantages of the embodiments of this utility model clearer, the technical solutions of the embodiments of this utility model will be clearly and completely described below with reference to the accompanying drawings.

[0014] This utility model provides an automatic calibration device for substation thermometers, such as... Figure 1 As shown, it includes a control module, an image acquisition module, a data transmission module, an image recognition module, and a human-machine interaction module. The control module is used to control the image acquisition module to acquire image data of the thermometer dial and the constant temperature bath display interface. The data transmission module is used to send the image data to the image recognition module to extract the temperature display values ​​of the thermometer dial and the substation constant temperature bath display interface, and then send the extracted temperature display values ​​to the human-machine interaction module. The human-machine interaction module is used to verify the temperature display values.

[0015] Specifically, for the control module, this invention uses Siemens' S7-200SMAR PLC and programs it to output a pulse node command at equal intervals, and to respond to external inputs and return the input time.

[0016] The PLC was powered on and tested, with each group issuing 50 commands, for a total of 10 groups. The continuity of the nodes was tested using a multimeter, and the PLC response test results are shown in Table 1.

[0017] Table 1 PLC Output Response Test Table

[0018]

[0019] Conclusion: The S7-200SMAR PLC used can achieve a program and hardware control accuracy of >99.5%, which meets the countermeasure objectives.

[0020] Specifically, for the image acquisition module, this invention utilizes the QOER button-type dual-screen action camera from Shenzhen TrueVision Technology Co., Ltd., based on the requirement of a camera with more than 20 megapixels. After reviewing relevant parameters, this camera features 64MP resolution, 30-meter waterproof capability, a 170° ultra-wide-angle lens, and 6-axis dynamic electronic image stabilization, fully meeting the needs of the actual on-site conditions. The camera controller and other components are fixed on the PCB board, and the camera controller is connected to the PLC and the thermometer alarm input.

[0021] Based on the actual site requirements, the thermometer dial is located approximately 1.5m above the ground, and the constant temperature bath is located on top of the main transformer. Therefore, a sturdy, compact bracket that can extend to 1.5m is needed. This invention uses a ColorNowDGNZPG A01 tripod as the camera bracket. Figure 2 As shown.

[0022] This invention conducted four sets of tests to test whether the camera could normally receive PLC control commands and take pictures. In each set, the PLC issued 100 picture commands at 1-second intervals to test the picture taking function and accuracy at equal intervals. The experimental data are shown in Table 2.

[0023] Table 2 Shooting Accuracy

[0024] Test number Group 1 Group 2 Group 3 Group 4 Overall accuracy Shooting accuracy 100％ 99％ 100％ 100％ 99.75％

[0025] Specifically, for the data transmission module, this invention has customized two 12-meter Type-C data cables to enable data transmission between the camera above the main transformer and the ground-based laptop.

[0026] To ensure its safety, durability, and reliability during use, reduce problems such as charging interruption and data transmission failure caused by breakage, and improve ease of use, this utility model conducted a tensile strength test on the data cable, and the test results are shown in Table 3.

[0027] Table 3 Tensile Strength Test of Type-C Data Cable

[0028] Test number Tensile strength (N) Type-C data cable status 1 10 intact 2 20 intact 3 30 intact 4 40 intact 5 50 intact 6 60 intact 7 70 intact 8 80 intact 9 90 intact 10 100 intact 11 110 intact 12 120 intact 13 130 intact 14 140 intact 15 150 Skin cracking

[0029] This invention successfully transferred a 1GB photo file to a computer via a Type-C data cable through 15 experiments, and the data transfer rate is shown in Table 4.

[0030] Table 4. Type-C Data Cable Transmission Rate

[0031]

[0032] Conclusion: After 15 tensile strength tests, the tensile strength was confirmed to be >100N; after 20 Type-C data cable transmission rate tests, the transmission rate was found to be ≥3Gbps, which meets the countermeasure objectives.

[0033] Specifically, for the image recognition module, this invention uses existing technologies for image recognition, such as convolutional neural networks or OpenCV (Open Source Computer Vision Library).

[0034] Specifically, for the human-computer interaction module, this invention selects the Weintek TK8072iP touchscreen and develops the display interface and button interaction program according to the requirements of the human-computer interaction module. The PLC is connected to the Weintek TK8072iP touchscreen using a network cable, and the display program is imported.

[0035] For the connected human-computer interaction interface, this utility model conducted 5 sets of tests on the screen display error rate and the correctness of key parameter input. The parameters were set 50 times in each set, and the test results are shown in Table 5.

[0036] Table 5 shows the results displayed on the interface.

[0037]

[0038] Conclusion: In summary, the five sets of experiments conducted by the group on the human-computer interaction interface, with parameters set 50 times in each set, all showed complete and clear display with a false display rate of <1% and a parameter input accuracy rate of 99.2% > 99%, thus meeting the policy objectives.

[0039] The automatic calibration device of this invention also includes a power supply module, which provides power to each module. This invention uses an AC 220V to DC 24V (LM7824CT) circuit, which mainly relies on diode rectification, capacitor filtering, and voltage regulation by a voltage regulator chip to achieve the conversion of 220V AC to 24V DC.

[0040] This invention connects the power supply to different loads and tests its output voltage and power output. The test results are shown in Table 6.

[0041] Table 6. Test Results of Power Output Voltage and Power

[0042]

[0043] Conclusion: The power supply voltage output range is 23.8~24.4V, and the temperature rise after 2 hours of operation is less than 5℃, indicating that the power supply is operating well. The tested maximum power output is 187W, which meets the countermeasure objectives of AC input 220V, DC output 20.4~28.8V, and maximum output power >50W.

[0044] After the device is assembled, the thermometer is tested using spare thermometer parts from a warehouse. First, the camera, the fully automatic thermometer calibration device, the constant temperature bath, the computer, and the AC power supply are set up and connected. The constant temperature bath and the fully automatic thermometer calibration device are run synchronously. The computer runs an image recognition system to record the thermometer dial data and constant temperature bath operation data photos in real time under different device states. The test image recognition results are shown in Table 7.

[0045] Table 7 Image Recognition Test Results

[0046]

[0047]

[0048] The test results were obtained by taking photos of the thermometers when the alarm nodes at 60℃, 70℃, 85℃, and 95℃ were activated. The test data for the thermometer nodes are shown in Table 8.

[0049] Table 8. Test data for thermometer nodes

[0050]

[0051] Conclusion: Through simulation testing using the automatic thermometer calibration device, the team members found that the device could correctly collect data from the constant temperature bath and thermometer dial, as well as the temperature values ​​at all four pairs of nodes. The device was able to start and run successfully, with a success rate of >99.8% and a calibration result integrity rate of >99%, meeting the policy objectives.

[0052] The above description is merely a preferred embodiment of this utility model. It should be understood that this utility model is not limited to the forms disclosed herein and should not be construed as excluding other embodiments. It can be used in various other combinations, modifications, and environments, and can be altered within the scope of the concept described herein through the above teachings or related technologies or knowledge. Modifications and variations made by those skilled in the art that do not depart from the spirit and scope of this utility model should be protected within the scope of the appended claims.

Claims

1. An automatic calibration device for substation thermometers, characterized in that, It includes a control module, an image acquisition module, a data transmission module, an image recognition module, a human-machine interaction module, and a power supply module. The control module controls the image acquisition module to acquire image data from the thermometer dial and the constant temperature bath display interface. The data transmission module sends the image data to the image recognition module to extract the temperature display values ​​from the thermometer dial and the substation constant temperature bath display interface, and then sends the extracted temperature display values ​​to the human-machine interaction module. The human-machine interaction module is used to verify the temperature display values. The power supply module provides power to all modules.

2. The automatic calibration device for substation thermometers according to claim 1, characterized in that, The control module is a PLC S7-200SMAR.

3. The automatic calibration device for substation thermometers according to claim 2, characterized in that, The image acquisition module uses a QOER button-type dual-screen action camera, and the controller of the action camera is connected to the PLC.

4. The automatic calibration device for substation thermometers according to claim 3, characterized in that, The automatic thermometer calibration device also includes a retractable camera bracket, the maximum extension of which corresponds to the height of the thermometer dial.

5. The automatic calibration device for substation thermometers according to claim 1, characterized in that, The human-computer interaction module uses a TK8072iP touchscreen.

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