Multifunctional distributed cable monitoring device and control method thereof

Abstract

The invention discloses a multifunctional distributed cable monitoring device and system, the device comprises a cable module, an infrared image monitoring module, a positioning module, a temperature and humidity sensor module, a dual power supply module and a main controller module, the cable module is provided with a signal conditioning circuit, the infrared image monitoring module is provided with a video processing module, and the positioning module is provided with a wireless communication module. The positioning module is used for uploading positioning coordinates monitored in real time to the main controller module; the temperature and humidity sensor module is used for inputting collected temperature and humidity data to the main controller module; the dual-power-supply module adopts a photovoltaic panel and a ternary lithium battery for combined power supply. The cable solves the problems that the cable is difficult to monitor in a low-temperature environment, high in pollution and inaccurate in signal in an interference environment and the like, and has the functions of independent power supply, simple installation, real-time monitoring and the like.

Description

TECHNICAL FIELD

[0001] The present application belongs to the technical field of cable monitoring, and particularly relates to a multifunctional distributed cable monitoring device and a control method thereof. BACKGROUND

[0002] At present, cable online monitoring devices have been widely used in power systems worldwide. Such devices mainly rely on sensing technology, communication technology and data analysis technology to achieve real-time monitoring of key parameters such as cable temperature, load and insulation state. However, in some special environments such as low temperature, high contamination, inability to access power supply and frequent movement of equipment, the device cannot meet the actual needs, and there are problems such as inaccurate data and false alarms, which cause great trouble to maintenance personnel. The current technology has the problems of poor environmental adaptability, unstable monitoring, lack of independent power supply and difficulty in frequent movement and installation. SUMMARY

[0003] (I) Invention purpose The purpose of the present application is to provide a multifunctional distributed cable monitoring device and a control method thereof, which solves the problems of difficult monitoring of cables in low temperature environments, inaccurate signals in high contamination and interference environments, and at the same time has the functions of independent power supply, simple installation and real-time monitoring.

[0004] (II) Technical solution To solve the above problems, the first aspect of the present application provides a multifunctional distributed cable monitoring device, which comprises a cable module, an infrared image monitoring module, a positioning module, a temperature and humidity sensor module, a dual power supply module and a main controller module, wherein: The cable module is provided with a signal conditioning circuit, and the cable module is used to input the monitored voltage and current analog signals to the main controller module after processing by the signal conditioning circuit; The infrared image monitoring module is provided with a video processing module, and the infrared image monitoring module is used to input the collected environmental information to the main controller module after processing by the video processing module; The positioning module is used to upload the real-time monitoring positioning coordinates to the main controller module; The temperature and humidity sensor module is used to input the collected temperature and humidity data to the main controller module; The dual power supply module adopts joint power supply of photovoltaic panels and ternary lithium batteries, and the dual power supply module is electrically connected with the cable module, the infrared image monitoring module, the positioning module, the temperature and humidity sensor module and the main controller module.

[0005] Preferably, the cable module is built-in with a voltage transformer, which outputs a 0-5V analog signal, which is processed by a signal conditioning circuit and then input to the ADC port of the main controller module for analysis.

[0006] Preferably, the cable module is built-in with a current transformer, which outputs a 0-20mA analog signal, which is processed by a signal conditioning circuit and then converted into a 0-3.3V voltage signal, and then input to the ADC port of the main controller module for analysis.

[0007] Preferably, the dual power supply module is built-in with an MPPT voltage conversion unit, and the electrical energy output by the photovoltaic panel is first transmitted to the MPPT voltage conversion unit for voltage conversion, and then transmitted to the ternary lithium battery, and the control current during transmission is ≤5A.

[0008] Preferably, the dual power supply module is built-in with a voltage management unit, and the power output by the ternary lithium battery is adjusted by the voltage management unit, and then used to supply power to the cable module, the infrared image monitoring module, the positioning module, the temperature and humidity sensor module and the main controller module.

[0009] Preferably, the infrared image monitoring module is built-in with a high-definition camera, which transmits the collected raw images to the video processing module through an HDMI interface for processing, and then uploads them to the USB port of the main controller module for analysis.

[0010] Preferably, the infrared image monitoring module further comprises an infrared ray sensor, a microphone and a loudspeaker, wherein: The infrared ray sensor transmits the collected infrared data to the SPI port of the main controller module. The microphone is provided with an audio conditioning circuit, and the microphone inputs the collected environmental sound to the ADC port of the main controller module for analysis after processing by the audio conditioning circuit. The loudspeaker is provided with an audio drive circuit, which is used to receive and amplify the signal from the PWM port of the main controller module to drive the loudspeaker to produce sound.

[0011] Preferably, the positioning module comprises a Beidou positioning unit, which transmits data through a 4G or 5G signal transmitter.

[0012] Preferably, the temperature and humidity sensor module obtains power from the ternary lithium battery through a DC-DC converter.

[0013] In addition, the second aspect of the present application provides a control method of the multifunctional distributed cable monitoring device according to any one of the above descriptions, which comprises: The multifunctional distributed cable monitoring device is installed at two ends of the cable respectively, when the cable fails, the voltage and current signals at two ends of the fault point are collected respectively, and the relative distance between the fault point and the monitoring device is calculated by using a fault ranging algorithm; Combined with the relative distance, the absolute coordinates of the Beidou positioning unit in the monitoring device and the cable direction, a coordinate conversion formula is constructed, and the absolute coordinates of the fault point are obtained by using the coordinate conversion formula.

[0014] (Three) beneficial effects The above technical scheme of the present application has the following beneficial technical effects: the present application provides a multifunctional distributed cable monitoring device and its control method, the cable module in the device is provided with a signal conditioning circuit, the cable module is used to input the monitored voltage and current analog signals to the main controller module after processing by the signal conditioning circuit, the design of the cable module solves the signal drift problem caused by environmental interference, and can ensure that the signal accuracy is greatly improved. The infrared image monitoring module, the positioning module and the temperature and humidity sensor module are deeply integrated, and through the synergistic effect of signal verification and accurate perception, the technical problem of "single signal easy to misreport" is effectively solved. The dual power supply module adopts photovoltaic panel and ternary lithium battery combined power supply, and through the independent power supply guarantee mechanism, the signal interruption problem caused by "unstable power supply" is effectively solved. The present application solves the problems of difficult monitoring of the cable in low temperature environment, inaccurate signal in high pollution and interference environment, etc., and simultaneously has the functions of independent power supply, simple installation, real-time monitoring, etc. BRIEF DESCRIPTION OF DRAWINGS

[0015] Figure 1 is a schematic diagram of the multifunctional distributed cable monitoring device of the present application; Figure 2 is a control method flow chart of the multifunctional distributed cable monitoring device of the present application.

[0016] Figure number: 1, cable module; 2, infrared image monitoring module; 3, positioning module; 4, temperature and humidity sensor module; 5, dual power supply module; 6, main controller module. DETAILED DESCRIPTION

[0017] In order to make the purpose, technical scheme and advantages of the present application more clear and explicit, the present application is further described in detail below in combination with specific embodiments and with reference to the drawings. It should be understood that these descriptions are only exemplary and are not intended to limit the scope of the present application. In addition, in the following description, the description of known structures and technologies is omitted to avoid unnecessary confusion of the concept of the present application.

[0018] As Figure 1As shown, the present application provides a multifunctional distributed cable monitoring device, which comprises a cable module 1, an infrared image monitoring module 2, a positioning module 3, a temperature and humidity sensor module 4, a dual power supply module 5 and a main controller module 6, wherein: The cable module 1 is provided with a signal conditioning circuit, and the cable module 1 is used for inputting the monitored voltage and current analog signals to the main controller module 6 after processing by the signal conditioning circuit. The outer layer of the cable module 1 is provided with a protective shell, the protective shell is made of glass fiber and epoxy resin material, the inside is filled with polyurethane except electronic components, and functions such as cable support, isolation from the ground, waterproof and heat insulation of electronic components are realized. The polyurethane filling layer isolates the internal electronic components from the external low temperature environment, so that the component working temperature is maintained at-30℃~+60℃(rated working range), and signal drift (such as temperature and humidity sensor zero point deviation) caused by too low temperature is avoided. The glass fiber + epoxy resin shell can effectively prevent rainwater, industrial dirt (such as coal dust, sludge) from entering the inside of the support, and avoid signal short circuit / attenuation of sensors (such as temperature and humidity module, current transformer) caused by contact with dirt.

[0019] The cable module 1 is provided with a voltage transformer PT, and the voltage transformer outputs a 0-5V analog signal, which is processed by a signal conditioning circuit and input to the ADC port of the main controller module for analysis. The shell of the cable module 1 is also provided with a current transformer CT, and the current transformer outputs a 0-20mA analog signal, which is processed by a signal conditioning circuit and converted into a 0-3.3V voltage signal, and then input to the ADC port of the main controller module 6 for analysis. The PT adopts an "open type" structure, and the CT adopts a "through type" structure, without the need to disconnect the cable, and the installation position is at the cable terminal such as the junction box and the switch compartment. The PT / CT signal conditioning circuit is set to 12V / 0.2A, for example, for amplifying the weak signal of PT / CT.

[0020] The infrared image monitoring module 2 is provided with a video processing module, and the infrared image monitoring module 2 is used for inputting the collected environmental information to the main controller module 6 after processing by the video processing module. The infrared image monitoring module 2 is built-in with a high-definition camera, and the high-definition camera transmits the collected raw images to the video processing module through an HDMI interface for processing, and then uploads them to the USB port of the main controller module for analysis. The signal transmission is as follows: high-definition camera (1080P, HDMI interface)→ video processing module (HI3516CV500, compressed to H.264 format)→ main controller USB port (transmit compressed video data). The infrared image monitoring module 2 is used for monitoring the environment around the device, and for preset scene alarm, voice reminder, and remote human-computer interaction.

[0021] The infrared image monitoring module 2 further comprises an infrared ray sensor, a microphone and a speaker, wherein: the infrared ray sensor transmits the collected infrared data to the SPI port of the main controller module, and the signal collection loop is as follows: infrared sensor (MLX90640, 16x16 pixels) → main controller SPI port (sampling rate 10 frames / second, thermal imaging data acquisition). When the device is running, personnel and vehicles approach the live cable, the infrared image monitoring module captures images and uploads them to the cloud server, and the data comparison issues a warning voice to remind personnel to stay away from the live equipment. The infrared sensor (wavelength 8-14 μm) can penetrate smoke, dust and slight contamination, and can still accurately capture targets such as fire sources and cable heating points in a high-interference environment. For example, in a fire, the infrared signal is not blocked by smoke and can accurately locate the fire source.

[0022] An audio conditioning circuit is arranged on the microphone, the microphone inputs the collected environmental sound to the ADC port of the main controller module for analysis after processing by the audio conditioning circuit, and the specific signal collection loop is as follows: microphone (electret, output 0-1V analog signal) → audio conditioning circuit (amplification + band-pass filtering, 100Hz-3kHz) → main controller ADC port.

[0023] An audio drive circuit is arranged on the speaker, the audio drive circuit is used for receiving and amplifying the signal of the PWM port of the main controller module to drive the speaker to sound, and the specific signal collection loop is as follows: speaker (8Ω / 5W) → audio drive circuit (TDA2822) → main controller PWM port.

[0024] The positioning module 3 is used for uploading the real-time monitored positioning coordinates to the main controller module 6. The positioning module comprises a Beidou positioning unit, and the Beidou positioning unit transmits data through a 4G or 5G signal transmitter. When the device is running, the Beidou positioning coordinates are uploaded to the cloud server in real time, the data are accessed to the main controller (background system), and the real-time positioning and tracking of the cable can be realized, which is convenient for maintenance and operation personnel to inspect.

[0025] The temperature and humidity sensor module 4 is used to input the collected temperature and humidity data to the main controller module 6. The temperature and humidity sensor module obtains power supply from the ternary lithium battery through the DC-DC converter, for example, the working parameter of the temperature and humidity sensor module 4 is set to 3.3V / 0.1A, and the power supply is obtained from the 12V power supply through the DC-DC converter. The temperature and humidity sensor module 4 is about 5cm away from the cable module to avoid the influence of cable heating on temperature and humidity measurement. When the device is running, a fire occurs around, the temperature and humidity sensor module 4 detects that the surrounding temperature rises, and the background reports temperature anomaly, the infrared monitoring detects the fire image, and prompts the fire warning. If there is water around, the temperature and humidity sensor module 4 detects that the surrounding humidity rises, and the background reports humidity anomaly, the image monitoring system captures the image, and prompts the water warning.

[0026] The dual power supply module 5 adopts photovoltaic panel and ternary lithium battery combined power supply to form an independent power supply system. The application includes a power supply circuit and a signal acquisition circuit, adopts a "centralized power supply + scattered acquisition" mode, ensures voltage stability and signal without attenuation. The ternary lithium battery is packaged with a waterproof plastic box. The application adopts a dual power supply mode of photovoltaic panel and ternary lithium battery, for example: photovoltaic panel (power≥50W) + ternary lithium battery (capacity≥100Ah), the photovoltaic panel can charge the infrared image monitoring system and the battery pack, and the battery pack adopts ternary lithium battery to supply power to the device when the photovoltaic panel does not work. Photovoltaic panel charging: under the condition of light, the photovoltaic panel charges the infrared image monitoring module 2 (power consumption≤10W) and the battery pack, which meets the daily operation demand. At night / dark day (photovoltaic panel does not work), the ternary lithium battery (low-temperature discharge efficiency≥80%, still can normally supply power under-30℃ environment) provides continuous power supply for the equipment, and guarantees uninterrupted monitoring signal.

[0027] The dual power supply module 5 is electrically connected with the cable module 1, the infrared image monitoring module 2, the positioning module 3, the temperature and humidity sensor module 4 and the main controller module 6 respectively. The dual power supply module 5 is built-in voltage management unit, the power output by the ternary lithium battery is adjusted by the voltage management unit, and then supplies power to the cable module 1, the infrared image monitoring module 2, the positioning module 3, the temperature and humidity sensor module 4 and the main controller module 6 respectively. The dual power supply module 5 is built-in MPPT voltage conversion unit, the electric energy output by the photovoltaic panel is first transmitted to the MPPT voltage conversion unit for voltage conversion, and then transmitted to the ternary lithium battery, and the current control is≤5A in the transmission process.

[0028] The combination of the above cable module 1, infrared image monitoring module 2 and temperature and humidity sensor module 4 multi-source data cross verification example is as follows: For example, fire monitoring application: the temperature and humidity sensor module 4 detects that the ambient temperature is greater than or equal to 60 DEG C (trigger threshold), the infrared image monitoring module 2 captures the image of the open fire / high temperature heat source, and the background compares the cable branch voltage / current data in the cable module 1 (if the three-phase current deviation is greater than or equal to 15%, it is determined that the cable is affected by fire). The combination of the three avoids the problems of "steam causing temperature false alarm" or "false touch causing image misjudgment".

[0029] For example, water monitoring application: the temperature and humidity sensor module 4 detects that the ambient humidity is greater than or equal to 90% RH (trigger threshold), the high-definition camera captures the image of the ground water / cable immersion, and verifies that it is a real water event, not a false alarm caused by "air humidity". Then the voice interaction between the operation and maintenance personnel and the scene is realized through the loudspeaker / microphone, and the camera angle can be remotely instructed to further confirm the signal authenticity (such as suspected failure, remotely control the camera to zoom in on the local image to determine whether it is a false alarm. The false alarm rate is reduced from 15% to 20% in the prior art to less than or equal to 3% (based on the field test data of the power plant).

[0030] As shown in Figure 2 The second aspect of the present application provides a control method of the multifunctional distributed cable monitoring device according to any one of the above descriptions, comprising: S1, the multifunctional distributed cable monitoring device is installed at both ends of the cable, and when the cable fails, the voltage and current signals at both ends of the fault point are collected, and the relative distance between the fault point and the monitoring device is calculated by using a fault ranging algorithm; S2, combining the relative distance, the absolute coordinates of the Beidou positioning unit in the monitoring device and the cable direction, a coordinate conversion formula is constructed, and the absolute coordinates of the fault point are obtained by using the coordinate conversion formula.

[0031] The control method will be described below in conjunction with specific embodiments: Taking a typical 10kV distribution network cable overhead line as an example, sensors and monitoring hosts are installed at both ends of the cable line, when a fault occurs, the sensors collect power frequency signals and transient signals, which are transmitted to the host, the monitoring host is uploaded to the host station through wireless communication, the monitoring host station judges the fault section through the uploaded fault information, and the specific steps are as follows: First step: fault ranging (calculate relative distance L) Fault ranging is the core, and the commonly used impedance method (suitable for low resistance fault) and traveling wave method (suitable for high resistance fault) are used. The following will take the double-end impedance method (higher precision) as an example to illustrate: Principle of this step: When fault occurs, the monitoring devices (A, B) at both ends of the cable collect the voltage (UA, UB) and current (IA, IB) of the fault phase, and calculate the distance (LA) from the fault point to end A and the distance (LB) from the fault point to end B according to the fault loop impedance, where LA + LB = L_total (total length of the cable).

[0032] Take single-phase grounding fault as an example: The apparent impedance (Zf) of the fault point is: ; Where: UA: A-end fault phase voltage (V); IA: A-end fault phase current (A); I0: A-end zero sequence current (A); k0: Zero sequence current compensation coefficient (determined by cable parameters).

[0033] The distance (LA) of the fault point from end A is: ; Where is the real part (resistance component) of the apparent impedance, r1 is the unit length positive sequence resistance of the cable (Ω / m), and r0 is the unit length zero sequence resistance of the cable (Ω / m).

[0034] Step 2: Coordinate conversion (relative distance → absolute coordinates) After obtaining the relative distance (LA) of the fault point from the monitoring device, the absolute coordinates of the fault point need to be converted in combination with the Beidou coordinates of the monitoring device and the cable orientation. The specific steps are as follows: Step 1: Obtain the absolute coordinates of the monitoring device: The Beidou positioning module sends the coordinates (Lon1, Lat1) of the A-end monitoring device to the main controller (e.g., Lon1 = 116.3975°, Lat1 = 39.9087°).

[0035] Step 2: Determine the cable orientation (direction angle θ): The orientation of the cable is obtained from design drawings or field measurement (e.g., the direction angle θ of the cable from end A to end B is 30°, i.e., 30° north by east).

[0036] Step 3: Calculate the relative coordinate offset of the fault point: The eastward offset (ΔLon) and northward offset (ΔLat) of the fault point relative to end A are: ; ; Where: R: Earth radius (about 6371 km = 6.371 × 10 6 m); cos(Lat1): Latitude correction factor (to avoid distance errors caused by different latitudes).

[0037] Step 4: Calculate the absolute coordinates of the fault point: The absolute coordinates (Lon2, Lat2) of the fault point are: Lon2 = Lon1 + ΔLon; Lat2 = Lat1 + ΔLat.

[0038] It should be understood that the specific embodiments described above are merely illustrative or explanatory of the principles of the invention and do not constitute a limitation thereof. Therefore, any modifications, equivalent substitutions, improvements, etc., made without departing from the spirit and scope of the invention should be included within the protection scope of the invention. Furthermore, the appended claims are intended to cover all variations and modifications falling within the scope and boundaries of the appended claims, or equivalent forms of such scope and boundaries. Those skilled in the art will understand that embodiments of the invention can be provided as methods, systems, or computer program products. Therefore, the invention can take the form of a completely hardware embodiment, a completely software embodiment, or an embodiment combining software and hardware aspects. Moreover, the invention can take the form of a computer program product embodied on one or more computer-usable storage media (including, but not limited to, disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code. These computer program instructions can also be stored in a computer-readable storage medium capable of directing a computer or other programmable data processing device to operate in a particular manner, such that the instructions stored in the computer-readable storage medium produce an article of manufacture including instruction means implemented in a process. Figure 1 One or more processes and / or boxes Figure 1 The functions specified in one or more boxes. Those skilled in the art will understand that all or part of the steps in the methods of the above embodiments can be implemented by a program instructing related hardware. The program can be stored in a computer-readable storage medium, and when executed, it includes the flows of the embodiments of the methods described above. The storage medium can be a magnetic disk, optical disk, read-only memory (ROM), or random access memory (RAM), etc. The steps in the methods of the embodiments of the present invention can be adjusted, merged, and deleted according to actual needs. The modules in the system of the embodiments of the present invention can be merged, divided, and deleted according to actual needs.

Claims

1. A multifunctional distributed cable monitoring device, characterized in that, It includes a cable module, an infrared image monitoring module, a positioning module, a temperature and humidity sensor module, a dual power supply module, and a main controller module, among which: The cable module is equipped with a signal conditioning circuit, which processes the monitored voltage and current analog signals and then inputs them to the main controller module. The infrared image monitoring module is equipped with a video processing module, which processes the collected environmental information and then inputs it to the main controller module. The positioning module is used to upload the real-time monitored positioning coordinates to the main controller module; The temperature and humidity sensor module is used to input the collected temperature and humidity data to the main controller module; The dual power supply module uses a combination of photovoltaic panels and ternary lithium batteries for power supply. The dual power supply module is electrically connected to the cable module, infrared image monitoring module, positioning module, temperature and humidity sensor module and main controller module, respectively.

2. The multifunctional distributed cable monitoring device according to claim 1, characterized in that, The cable module has a built-in voltage transformer, which outputs a 0-5V analog signal. After being processed by the signal conditioning circuit, the signal is input to the ADC port of the main controller module for analysis.

3. The multifunctional distributed cable monitoring device according to claim 1, characterized in that, The cable module has a built-in current transformer, which outputs a 0-20mA analog signal. After being processed by the signal conditioning circuit, the signal is converted into a 0-3.3V voltage signal and then input to the ADC port of the main controller module for analysis.

4. The multifunctional distributed cable monitoring device according to claim 1, characterized in that, The dual power supply module has a built-in MPPT voltage conversion unit. The electrical energy output by the photovoltaic panel is first sent to the MPPT voltage conversion unit for voltage conversion, and then transmitted to the ternary lithium battery. During the transmission process, the current is controlled to be ≤5A.

5. The multifunctional distributed cable monitoring device according to claim 1, characterized in that, The dual power supply module has a built-in voltage management unit. The power output from the ternary lithium battery is regulated by the voltage management unit and then used to power the cable module, infrared image monitoring module, positioning module, temperature and humidity sensor module, and main controller module, respectively.

6. The multifunctional distributed cable monitoring device according to claim 1, characterized in that, The infrared image monitoring module has a built-in high-definition camera. The high-definition camera transmits the raw images it captures to the video processing module via the HDMI interface for processing, and then uploads them to the USB port of the main controller module for analysis.

7. The multifunctional distributed cable monitoring device according to claim 1, characterized in that, The infrared image monitoring module also includes an infrared ray sensor, a microphone, and a speaker, wherein: The infrared ray sensor transmits the collected infrared data to the SPI port of the main controller module; The microphone is equipped with an audio conditioning circuit. The ambient sound collected by the microphone is processed by the audio conditioning circuit and then input to the ADC port of the main controller module for analysis. The speaker is equipped with an audio driving circuit, which is used to receive and amplify the signal from the PWM port of the main controller module to drive the speaker to produce sound.

8. The multifunctional distributed cable monitoring device according to claim 1, characterized in that, The positioning module includes a BeiDou positioning unit, which transmits data via a 4G or 5G signal transmitter.

9. The multifunctional distributed cable monitoring device according to claim 1, characterized in that, The temperature and humidity sensor module is powered by a ternary lithium battery via a DC-DC converter.

10. A control method for a multifunctional distributed cable monitoring device according to any one of claims 1-9, comprising: Multifunctional distributed cable monitoring devices are installed at both ends of the cable. When a cable fault occurs, the voltage and current signals at both ends of the fault point are collected, and the relative distance between the fault point and the monitoring device is calculated using a fault distance algorithm. By combining the relative distance, the absolute coordinates of the Beidou positioning unit in the monitoring device, and the cable routing, a coordinate transformation formula is constructed, and the absolute coordinates of the fault point are obtained using the coordinate transformation formula.

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