Electric leakage detection device and electric leakage detection method for operation and maintenance of extra-high voltage converter station

Abstract

The invention relates to the technical field of electric leakage detection devices for extra-high voltage converter stations, in particular to an electric leakage detection device for operation and maintenance of an extra-high voltage converter station and an electric leakage detection method.The electric leakage detection device comprises a walking mechanism, a robot assembly and an electric leakage detector, and the robot assembly is installed on the upper side of the walking mechanism and comprises a controller; the robot assembly is provided with a folding telescopic arm, the upper end face of the folding telescopic arm is rotationally connected with an electric leakage detector, the electric leakage detector comprises an outer shell, the left side and the right side of the outer shell are provided with an air inlet grille and an air outlet correspondingly, and a fan is arranged in the position, close to the air outlet, of the outer shell. And an air inlet of the fan is connected with the air inlet grille through an air guide channel. The high-voltage electric leakage detection device is reasonable and compact in structure and convenient to use, the high-voltage electric leakage danger is rapidly determined by detecting ozone and charged negative ions generated in the electric leakage process, flexible operation can be conducted in a narrow or high-altitude environment through the folding telescopic arm, and the requirement of a complex inspection task is met.

Description

Technical Field

[0001] This invention relates to the technical field of leakage current detection devices for ultra-high voltage converter stations, and is a leakage current detection device and method for operation and maintenance of ultra-high voltage converter stations. Background Technology

[0002] Ultra-high voltage (UHV) converter stations are crucial for the normal operation of power systems. The biggest concern during operation is high-voltage leakage. If a leakage occurs, the leaking current will generate ion discharge in the air. Traditional methods for detecting leakage in UHV converter stations involve workers inspecting the valve hall with a blowtorch, continuously spraying flames. A flame, the hot, luminous, and vaporized part of fire, can be called plasma. Plasma, also known as electrostatic discharge, is essentially an ionized gaseous substance composed of a large number of electrons originally bound to gas molecules (atoms) gaining energy and becoming free electrons, producing positive and negative ions. Both flames and electric currents are forms of plasma. High-voltage leakage generates ion discharge, which in turn disturbs the air. Therefore, the current in the air affects the direction of the flame. The principle is that both the high-temperature flame and the current are plasmas and influence each other. Therefore, the flame generated by the blowtorch can be used to test for high-voltage leakage. When a large number of electrostatic nuclei move in one direction, the charged nuclei in the plasma will also move in that direction, indicating a leakage in the equipment.

[0003] Using the above operating steps, in practical applications, workers regularly carry flame torches to inspect and test inside the UHV converter station. The testing efficiency is low, and it is time-consuming and labor-intensive. When workers walk with the flame in their hands, the surrounding air will blow the flame, which can easily lead to misjudgment. At the same time, for leakage at high places in the UHV converter station, it is difficult to detect leakage faults when the inspection distance is too far. Summary of the Invention

[0004] This invention provides a leakage current detection device and method for operation and maintenance of ultra-high voltage converter stations, which overcomes the shortcomings of the prior art and can effectively solve the problems of low efficiency, time-consuming and labor-intensive, and low accuracy of existing manual inspection and detection in ultra-high voltage converter stations.

[0005] One of the technical solutions of this invention is achieved through the following measures: a leakage current detection device for operation and maintenance of an ultra-high voltage converter station, comprising a walking mechanism, a robot component, and a leakage current detector. The robot component is mounted on the upper side of the walking mechanism. The robot component includes a controller. A folding telescopic arm is mounted on the robot component. The upper end face of the folding telescopic arm is rotatably connected to the leakage current detector. The leakage current detector includes a housing. An air inlet grille and an air outlet are respectively provided on the left and right sides of the housing. A fan is provided inside the housing near the air outlet. The air inlet of the fan is connected to the air inlet grille through an air guide channel. A negative ion detector is provided inside the air guide channel. A sensor component and an ozone and environmental detection module are mounted on the outer side of the housing. The sensor component includes an ultrasonic detection sensor, an ultra-high frequency detection sensor, and a ground wave detection sensor. The ozone and environmental detection module includes a gas sensor, a temperature and humidity sensor, and an ozone concentration sensor. The fan, negative ion detector, sensor component, and ozone and environmental detection module are respectively connected to the controller.

[0006] The following are further optimizations and / or improvements to the above-mentioned technical solution:

[0007] Preferably, the robot components include a smart box, communication equipment, an emergency switch, and a temperature and humidity sensor. The communication equipment, emergency switch, and temperature and humidity sensor are installed on the outer side of the smart box. A charging interface is installed on the outer side of the smart box. A lithium battery pack and a controller are installed inside the smart box. The smart box is installed on the upper side of the walking mechanism.

[0008] Preferably, the folding telescopic arm consists of two telescopic arm sections, each with a torque motor connected to its end, and the torque motor is connected to the controller.

[0009] Preferably, the walking mechanism includes a chassis, with an obstacle avoidance camera and a lidar mounted on the outer side of the chassis, and four omnidirectional wheels and two drive wheels mounted on the lower side of the chassis. The two drive wheels are controlled independently by two walking motors, and the output shafts of the walking motors are connected to the axles of the corresponding drive wheels. The walking motors are connected to a controller.

[0010] Preferably, it also includes an image acquisition device, which includes a mounting bracket and a binocular camera. The mounting bracket is mounted on the housing, and the binocular camera is mounted on the mounting bracket. The binocular camera includes a visible light camera and an infrared thermal imager.

[0011] The second technical solution of the present invention is achieved through the following measures: a leakage current detection method, performed according to the following steps,

[0012] Step 1: Environment Modeling and Navigation Initialization

[0013] Start the lidar to scan the valve hall environment and build a 3D point cloud map; load the preset inspection path and set the safe distance threshold to 1.2m; start the binocular camera to warm up and calibrate the infrared thermal imager;

[0014] The second step is mobile inspection and data collection:

[0015] Control the walking mechanism to move along the planned path and collect in real time: visible light images, infrared temperature field, and ambient temperature and humidity data;

[0016] The third step is to perform a fixed-point leakage current detection by extending the folding telescopic arm to the target height; then, the fan is activated to extract air, which flows through the air guide channel, and the negative ion detector samples and calculates the concentration.

[0017]

[0018] In the formula, N ion Negative ion concentration (ions / cm³) 3 Q is the air extraction flow rate (m³ / s). 3 / s); t is the sampling time (s); V is the volume of the air delivery channel (0.05m³). 3 E is the electric field strength (kV / m); α and β are the sensor calibration coefficients.

[0019] Step 4: Multi-source data fusion determination:

[0020] Data synchronous acquisition: Real-time acquisition of negative ion concentration N ion ;

[0021] Read the ozone concentration sensor value C O3 ;

[0022] Extract the local maximum temperature rise ΔT detected by the infrared thermal imager. max ;

[0023] Record the partial discharge pulse count P of the ultra-high frequency sensor UHF ;

[0024] Output of the judgment result:

[0025] Level 1 Alert: Simultaneously, the concentration of negative ions, ozone concentration, and temperature rise all exceed the threshold.

[0026] Level 2 Alert: Negative Ion Concentration N ion or ozone concentration C O3 Single item exceeds standard and partial discharge pulse count P UHF >100 times;

[0027] Preferably, dynamic baseline calibration is performed before outputting the judgment result: negative ion concentration threshold N0 = 200 × (1 + 0.02ΔH), unit (ions / cm³). 3), ΔH: rate of temperature change; ozone threshold C0 = 0.1 × e -0.05T Unit: ppm; T: temperature (°C).

[0028] Preferably, it also includes a fifth step: tiered response and data upload.

[0029] 1) Emergency Response Mechanism:

[0030]

[0031] 2) Data upload protocol:

[0032] Content transmitted: Raw sensor data packets;

[0033] Alarm Decision Basis Matrix [N] ion C O3 ,ΔT max ,P UHF ];

[0034] Three-dimensional spatial coordinates;

[0035] Transmission method: 5G network preferred;

[0036] Backup microwave channel;

[0037] 3) Real-time visualization processing: Generate a risk heat map of the valve hall:

[0038]

[0039] This invention has a reasonable and compact structure and is easy to use. It can quickly identify high-voltage leakage hazards by detecting ozone and charged negative ions generated during leakage. The foldable telescopic arm can operate flexibly in narrow or high-altitude environments, meeting the needs of complex inspection tasks. Attached Figure Description

[0040] Appendix Figure 1 This is a schematic diagram of the main structure of an embodiment of the present invention.

[0041] Appendix Figure 2 This is a three-dimensional structural diagram of an embodiment of the present invention.

[0042] Appendix Figure 3 This is a top-view cross-sectional view of the leakage current detector.

[0043] Appendix Figure 4 This is a flowchart of a leakage current detection method.

[0044] The codes in the attached diagram are as follows: 11. Chassis; 12. Caster wheel; 13. Drive wheel; 14. Obstacle avoidance camera; 21. Smart box; 22. Communication equipment; 23. Emergency switch; 24. Temperature and humidity sensor; 3. Folding telescopic arm; 41. Air intake grille; 42. Negative ion detector; 43. Air duct; 44. Fan; 45. Air outlet; 46. Outer shell; 47. Sensor assembly; 48. Ozone and environmental detection module; 51. Mounting bracket; 52. Binocular camera. Detailed Implementation

[0045] The present invention is not limited to the following embodiments, and the specific implementation can be determined according to the technical solution of the present invention and the actual situation.

[0046] In this invention, for ease of description, the description of the relative positions of the components is based on the appendix to the specification. Figure 1 The layout is described using a diagrammatic method, such as front, back, top, bottom, left, right, etc. The positional relationships are determined based on the layout direction of the attached diagram in the instruction manual.

[0047] The present invention will be further described below with reference to embodiments and accompanying drawings:

[0048] Example 1: As shown in the attached document Figure 1-4 As shown, the leakage current detection device for the operation and maintenance of the UHV converter station includes a walking mechanism, a robot component, and a leakage current detector. The robot component, including a controller, is mounted on the upper side of the walking mechanism. A folding telescopic arm 3 is mounted on the robot component, and a leakage current detector is rotatably connected to the upper end face of the folding telescopic arm 3. The leakage current detector includes a housing 46, with an air inlet grille 41 and an air outlet 45 on the left and right sides of the housing 46, respectively. A fan 44 is located inside the housing 46 near the air outlet 45. The air inlet of the fan 44 is connected to... The air duct 43 is connected to the air intake grille 41. The air duct 43 is equipped with a negative ion detector 42. The outer side of the housing 46 is equipped with a sensor assembly 47 and an ozone and environmental detection module 48. The sensor assembly 47 includes an ultrasonic detection sensor, an ultra-high frequency detection sensor and a ground wave detection sensor. The ozone and environmental detection module 48 includes a gas sensor, a temperature and humidity sensor and an ozone concentration sensor. The fan 44, negative ion detector 42, sensor assembly 47 and ozone and environmental detection module 48 are respectively connected to the controller.

[0049] Based on requirements, the folding telescopic boom 3 is made of aluminum alloy, which has good stability and load-bearing capacity, and can ensure stable operation of the inspection equipment in high positions or narrow environments.

[0050] The device moves within the detection area via a walking mechanism. During the inspection, the ozone concentration sensor and negative ion detector 42 monitor the surrounding environment in real time. When a high-voltage leakage occurs, the air near the leakage point will be ionized and generate negative ions. The air to be tested is drawn into the negative ion detector 42 by the fan 44. The ozone concentration sensor and negative ion detector 42 detect the ozone and charged negative ions generated when the high-voltage leakage occurs and send the signal to the controller (microcontroller). The microcontroller controls the equipment to issue an early warning, which improves detection efficiency and accuracy and is less affected by wind.

[0051] The ozone and environmental detection module 48 includes a gas sensor, a temperature and humidity sensor, and an ozone concentration sensor. It supports multi-gas detection: an electrochemical sensor (detecting CO or NO2 gas), and infrared spectroscopy (detecting SF6 decomposition products), achieving ppm-level trace gas detection. Ozone detection uses ultraviolet absorption (wavelength 254nm), calculating the concentration based on the characteristic absorption rate of ozone molecules to ultraviolet light, with strong anti-interference capabilities (unaffected by water vapor). It also features collaborative diagnostics, indicating continuous discharge overheating of the device when ozone and CO rise simultaneously.

[0052] Sensor assembly 47 is a multimodal partial discharge detection system that integrates three complementary sensing technologies to acquire physical signals caused by insulation defects in high-voltage equipment in real time. Its specific detection parameters and data are as follows:

[0053]

[0054]

[0055] The aforementioned leakage current detection device for operation and maintenance of UHV converter stations can be further optimized and / or improved according to actual needs:

[0056] Example 2: As shown in the attached document Figure 1 , 2 As shown, the robot components include a smart box 21, a communication device 22, an emergency switch 23, and a temperature and humidity sensor 24. The communication device 22, emergency switch 23, and temperature and humidity sensor 24 are mounted on the outer side of the smart box 21. A charging port is installed on the outer side of the smart box 21. A lithium battery pack and a controller are installed inside the smart box 21. The smart box 21 is mounted on the upper side of the walking mechanism. All collected data and images are transmitted to a remote control platform via the wireless network built into the smart box 21 for remote monitoring and management by the user.

[0057] Example 3: As shown in the attached document Figure 1 , 2As shown, the folding telescopic boom 3 consists of two telescopic boom sections, each with a torque motor connected to its end. The torque motors are connected to a controller. Equipped with the 2m folding telescopic boom 3, the controller controls the torque motors to rotate, thereby controlling the boom's rotation to raise or lower, achieving free extension and retraction. This allows for inspection of high-altitude, narrow, or difficult-to-access areas.

[0058] Example 4: As shown in the appendix Figure 1 , 2 As shown, the walking mechanism includes a chassis 11. An obstacle avoidance camera 14 and a lidar are mounted on the outer side of the chassis 11. Four omnidirectional wheels 12 and two drive wheels 13 are mounted on the underside of the chassis 11. The two drive wheels 13 are controlled independently by two walking motors. The output shafts of the walking motors are connected to the axles of the corresponding drive wheels 13. The walking motors are connected to a controller. During operation, when performing inspections, the two walking motors drive one drive wheel 13 to rotate clockwise and the other counterclockwise, allowing the walking mechanism to rotate 360 ​​degrees on the ground. At this time, the obstacle avoidance camera 14 and lidar mounted on the outer side of the chassis 11 scan the surrounding environment and generate a 3D map. The controller then uses the generated 3D map to control the walking mechanism to move freely indoors for inspections.

[0059] Example 5: As shown in the attached document Figure 1 , 2 As shown, it also includes an image acquisition device, which includes a mounting bracket 51 and a binocular camera 52. The mounting bracket 51 is mounted on the outer casing 46, and the binocular camera 52 is mounted on the mounting bracket 51. The binocular camera 52 includes a visible light camera and an infrared thermal imager. During the walking mechanism's movement, it acquires real-time images through the binocular camera 52 and monitors the partial discharge of the equipment in real time through a leakage current detector.

[0060] Example 6: As attached Figure 1-4 As shown, the leakage current detection method is characterized by performing the following steps:

[0061] Step 1: Environment Modeling and Navigation Initialization

[0062] Start the lidar to scan the valve hall environment and build a 3D point cloud map; load the preset inspection path and set the safe distance threshold to 1.2m; start the binocular camera to warm up and calibrate the infrared thermal imager;

[0063] The second step is mobile inspection and data collection:

[0064] Control the walking mechanism to move along the planned path and collect in real time: visible light images, infrared temperature field, and ambient temperature and humidity data;

[0065] The third step is to perform a fixed-point leakage current detection by extending the folding telescopic arm to the target height; then, the fan is activated to extract air, which flows through the air guide channel, and the negative ion detector samples and calculates the concentration.

[0066]

[0067] In the formula, N ion Negative ion concentration (ions / cm³) 3 Q is the air extraction flow rate (m³ / s). 3 / s); t is the sampling time (s); V is the volume of the air delivery channel (0.05m³). 3 E is the electric field strength (kV / m); α and β are the sensor calibration coefficients.

[0068] Step 4: Multi-source data fusion determination:

[0069] Data synchronous acquisition: Real-time acquisition of negative ion concentration N ion ;

[0070] Read the ozone concentration sensor value C O3 ;

[0071] Extract the local maximum temperature rise ΔT detected by the infrared thermal imager. max ;

[0072] Record the partial discharge pulse count P of the ultra-high frequency sensor UHF ;

[0073] Output of the judgment result:

[0074] Level 1 Alert: Simultaneously, the concentration of negative ions, ozone concentration, and temperature rise all exceed the threshold.

[0075] Level 2 Alert: Negative Ion Concentration N ion or ozone concentration C O3 Single item exceeds standard and partial discharge pulse count P UHF >100 times;

[0076] By implementing the above steps to achieve automatic leakage current detection, the system can autonomously plan, execute, and analyze inspection tasks, thereby improving the level of intelligence in inspection work.

[0077] Example 7: As attached Figure 1-4 As shown, dynamic baseline calibration is performed before the judgment result is output: negative ion concentration threshold N0 = 200 × (1 + 0.02ΔH), unit (ions / cm). 3 ), ΔH: rate of temperature change; ozone threshold C0 = 0.1 × e -0.05T Unit: ppm; T: temperature (°C).

[0078] Ambient temperature and humidity can affect the test results and may lead to misjudgment. The above formula is used to calibrate the negative ion concentration threshold N0 and the ozone threshold C0 to make the alarm more accurate.

[0079] Example 8: As attached Figure 1-4 As shown, it also includes a fifth step: tiered response and data upload.

[0080] 1) Emergency Response Mechanism:

[0081]

[0082] 2) Data upload protocol:

[0083] Content transmitted: Raw sensor data packets;

[0084] Alarm Decision Basis Matrix [N] ion C O3 ,ΔT max ,P UHF ];

[0085] Three-dimensional spatial coordinates;

[0086] Transmission method: 5G network preferred;

[0087] Backup microwave channel;

[0088] 3) Real-time visualization processing: Generate a risk heat map of the valve hall:

[0089]

[0090] The above steps can trigger interlocking actions after a leakage occurs, causing the circuit breaker in the station to trip to ensure safety, and marking the GPS coordinates of the abnormal point to facilitate the operation personnel to reach the designated location for maintenance.

[0091] The above technical features constitute various 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 leakage current detection device for operation and maintenance of ultra-high voltage converter stations, characterized in that... The system includes a walking mechanism, a robot component, and a leakage current detector. The robot component, including a controller, is mounted on the upper side of the walking mechanism. A folding telescopic arm is mounted on the robot component, and a leakage current detector is rotatably connected to the upper end of the folding telescopic arm. The leakage current detector includes a housing with an air inlet grille and an air outlet on its left and right sides, respectively. A fan is located inside the housing near the air outlet. The fan's air inlet is connected to the air inlet grille via an air guide channel. A negative ion detector is located inside the air guide channel. A sensor component and an ozone and environmental detection module are mounted on the outer side of the housing. The sensor component includes an ultrasonic sensor, a UHF sensor, and a ground wave sensor. The ozone and environmental detection module includes a gas sensor, a temperature and humidity sensor, and an ozone concentration sensor. The fan, negative ion detector, sensor component, and ozone and environmental detection module are all connected to the controller.

2. The leakage current detection device for operation and maintenance of ultra-high voltage converter stations according to claim 1, characterized in that... The robot components include a smart box, communication equipment, an emergency switch, and a temperature and humidity sensor. The communication equipment, emergency switch, and temperature and humidity sensor are installed on the outer side of the smart box. A charging port is installed on the outer side of the smart box. A lithium battery pack and a controller are installed inside the smart box. The smart box is installed on the upper side of the walking mechanism.

3. The leakage current detection device for operation and maintenance of ultra-high voltage converter stations according to claim 2, characterized in that... The folding telescopic arm consists of two telescopic arm sections, each with a torque motor connected to its end. The torque motor is connected to the controller.

4. The leakage current detection device for operation and maintenance of ultra-high voltage converter stations according to claim 2 or 3, characterized in that... The walking mechanism includes a chassis, with obstacle avoidance cameras and lidar mounted on the outside of the chassis. Four omnidirectional wheels and two drive wheels are mounted on the underside of the chassis. The two drive wheels are controlled independently by two walking motors. The output shafts of the walking motors are connected to the axles of the corresponding drive wheels, and the walking motors are connected to the controller.

5. The leakage current detection device for operation and maintenance of ultra-high voltage converter stations according to claim 1, 2, or 3, characterized in that... It also includes an image acquisition device, which includes a mounting bracket and a binocular camera. The mounting bracket is mounted on the housing, and the binocular camera is mounted on the mounting bracket. The binocular camera includes a visible light camera and an infrared thermal imager.

6. The leakage current detection device for operation and maintenance of ultra-high voltage converter stations according to claim 4, characterized in that... The image acquisition device includes a mounting bracket and a binocular camera. The mounting bracket is mounted on the housing, and the binocular camera is mounted on the mounting bracket. The binocular camera includes a visible light camera and an infrared thermal imager.

7. A leakage current detection method using the leakage current detection device for operation and maintenance of ultra-high voltage converter stations as described in claim 5 or 6, characterized in that... Follow these steps. Step 1: Environment Modeling and Navigation Initialization Start the lidar to scan the valve hall environment and build a 3D point cloud map; Load the preset inspection path and set the safety distance threshold to 1.2m; start the binocular camera to warm up and calibrate the infrared thermal imager; The second step is mobile inspection and data collection: Control the walking mechanism to move along the planned path and collect in real time: visible light images, infrared temperature field, and ambient temperature and humidity data; The third step is to perform a fixed-point leakage current detection by extending the folding telescopic arm to the target height; then, the fan is activated to extract air, which flows through the air guide channel, and the negative ion detector samples and calculates the concentration. In the formula, N ion Negative ion concentration (ions / cm³) 3 Q is the air extraction flow rate (m³ / s). 3 / s); t is the sampling time (s); V is the volume of the air delivery channel (0.05m³). 3 E is the electric field strength (kV / m); α and β are the sensor calibration coefficients. Step 4: Multi-source data fusion determination: Data synchronous acquisition: Real-time acquisition of negative ion concentration N ion ; Read the ozone concentration sensor value C O3 ; Extract the local maximum temperature rise ΔT detected by the infrared thermal imager. max ; Record the partial discharge pulse count P of the ultra-high frequency sensor UHF ; Output of the judgment result: Level 1 Alert: Simultaneously, the concentration of negative ions, ozone concentration, and temperature rise all exceed the threshold. Level 2 Alert: Negative Ion Concentration N ion or ozone concentration C O3 Single item exceeds standard and partial discharge pulse count P UHF >100 times.

8. The leakage current detection method according to claim 7, characterized in that... Dynamic baseline calibration is performed before outputting the judgment results: negative ion concentration threshold N0 = 200 × (1 + 0.02ΔH), unit (ions / cm³). 3 ), ΔH: rate of temperature change; ozone threshold C0 = 0.1 × e -0.05T Unit: ppm; T: temperature (°C).

9. The leakage current detection method according to claim 7 or 8, characterized in that... It also includes a fifth step: tiered response and data upload. 1) Emergency Response Mechanism: 2) Data upload protocol: Content transmitted: Raw sensor data packets; Alarm Decision Basis Matrix [N] ion ,C O3 ,ΔT max ,P UHF ]; Three-dimensional spatial coordinates; Transmission method: 5G network preferred; Backup microwave channel; 3) Real-time visualization processing: Generate a risk heat map of the valve hall:

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