Early warning device for grounding current of high-voltage cable

Abstract

The utility model discloses a high-voltage cable grounding current early warning device, and relates to the technical field of electrical safety monitoring. The utility model aims to solve the technical problems that the cable grounding fault cannot be quickly known and the problem cannot be found in time in the prior art. A high-voltage cable grounding current early warning device comprises a monitoring host, the monitoring host communicates with a remote terminal through a wireless transmission module, the remote terminal communicates with a cloud platform system, the monitoring host communicates with sensors, and the monitoring host is connected with power supplies of various voltage levels through a power supply module. According to the high-voltage cable grounding current early warning device, data of the main cable current and temperature monitoring sensor and the cable grounding current monitoring sensor are collected through the monitoring host, waveforms of the data are locally analyzed, an alarm is given and uploaded when alarm conditions are met, cable faults are judged through the cloud platform system, and early warning is carried out. The accuracy and timeliness of early warning are improved, manual inspection is not needed, manpower and material resources are reduced, and the cost is saved.

Description

Technical Field

[0001] The utility model relates to the technical field of electrical safety monitoring, in particular to a high-voltage cable grounding current early warning device. Background Technique

[0002] Power cables undertake the tasks of electric energy transmission and distribution and play a crucial role in urban power grids, outgoing lines of power stations, and power supply for industrial and mining enterprises. Due to the relatively harsh operating environment of cables, cable failures occur frequently caused by external force damage, chemical corrosion, mechanical vibration, and rodent and insect infestation. Many failures are manifested as changes in the grounding method and grounding current, especially the abnormal current generated by the multi-point grounding failure of the metal sheath is relatively common. Cable failures not only seriously threaten the safe operation of the power supply system but also pose great pressure on equipment operation and maintenance work. Chinese Patent with the publication number CN117873315A discloses an augmented reality device for power cable inspection, which is characterized by including a positioning module, a transmission module, a display module, a shooting module, and a management module. The positioning module automatically locates the geographical location and landmark facilities of the cable manhole, and displays the actual position of the inspection personnel in real time; the transmission module transmits the cable position information to the augmented reality device; the display module projects the cable information received by the transmission module onto the augmented reality device; the shooting module transmits the on-site photos taken by the augmented reality device to the in-field management personnel in real time; the management module reserves a data interface to access and manage multi-source data. This patent can assist in the tracing and route planning of power cable inspections. However, when this patent is used, it analyzes by having the inspection personnel take photos of the cable. Therefore, it cannot quickly understand the grounding faults of the cable, and problems cannot be discovered in time, which brings great hidden dangers to the reliability of the power supply system and cannot meet the requirements of modern power grid operation. Based on the above situation, establishing a set of intelligent management means to monitor the operating status of high-voltage cables in real time and online is a necessary means to ensure the safe operation of high-voltage cables. Content of the Utility Model

[0003] The purpose of the utility model is to provide a high-voltage cable grounding current early warning device, which has the functions of collecting the data of the main cable current, temperature monitoring sensors, and cable grounding current monitoring sensors through a monitoring host, locally analyzing their waveforms, comparing them with the characteristic waveform spectra, giving an alarm and uploading when the alarm conditions are met, collecting data, deeply analyzing, and integrating information through a cloud platform system, judging cable faults and giving early warnings, improving the accuracy and timeliness of early warnings, eliminating the need for manual inspections, reducing labor and material resources, and saving costs, and can solve the problems in the prior art.

[0004] To achieve the above object, the utility model provides the following technical solutions: A high-voltage cable grounding current warning device, including a monitoring host, the monitoring host communicates with a remote terminal through a wireless transmission module, the remote terminal communicates with a cloud platform system, the monitoring host communicates with sensors respectively, the sensors include a main cable current and temperature monitoring sensor and a cable grounding current monitoring sensor, the main cable current and temperature monitoring sensor and the cable grounding current monitoring sensor are both connected to the monitoring host through a multi-core cable, and the monitoring host is connected to power supplies of various voltage levels through a power module.

[0005] Preferably, the main cable current and temperature monitoring sensor includes a sensor housing, a main cable current measurement transformer core, a temperature measurement sensor, a water immersion sensor and a vibration sensor. The main cable current measurement transformer core, the temperature measurement sensor, the water immersion sensor and the vibration sensor are all arranged inside the sensor housing, and the current measurement transformer core is a ring-shaped core made of nanocrystalline material.

[0006] Preferably, the cable grounding current monitoring sensor is a low-power micro sensor. The cable grounding current monitoring sensor internally includes a circulating current monitoring sensor, a partial discharge monitoring sensor, a voltage induction coil and a current measurement coil. The cable grounding current monitoring sensor internally integrates multiple current measurement coils and an excitation coil, and the excitation coil and the induction coil are arranged alternately.

[0007] Preferably, the circulating current monitoring sensor includes a sensor housing, a circulating current measurement and grounding resistance current measurement core, a grounding resistance voltage induction core and a high-frequency pulse current transformer core.

[0008] Preferably, the monitoring host is an ARM+FPGA platform. The monitoring host internally is provided with a high-order FIR filter, and the monitoring host is internally provided with an information uploading module and a time calibration module.

[0009] Preferably, the cloud platform system is a cloud management system built on Alibaba Cloud, Tencent Cloud or other platforms.

[0010] Preferably, the power module includes a solar panel and a solar controller, and the solar panel is connected to the solar controller.

[0011] Compared with the prior art, the beneficial effects of the utility model are as follows:

[0012] This high-voltage cable grounding current warning device obtains electrical energy from the current flowing through the main cable through the main cable current and temperature monitoring sensor, and collects the working current from the current of the main cable joint. At the same time, it collects the temperature data of the main cable joint. The cable grounding current monitoring sensor detects and analyzes whether the cable grounding is good and whether there is a multi-point grounding situation. The monitoring host collects the data of the main cable current and temperature monitoring sensor and the cable grounding current monitoring sensor, and locally analyzes its waveform and compares it with the characteristic waveform spectrum. When the alarm condition is met, it alarms and uploads the data. The cloud platform system collects, deeply analyzes and integrates the data, judges the cable fault and gives an early warning, improving the accuracy and timeliness of the warning, eliminating the need for manual inspection, reducing manpower and material resources, and saving costs. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1 It is a connection schematic diagram of the present utility model;

[0014] Figure 2 It is a structural diagram of the main cable current and temperature monitoring sensor of the present utility model.

[0015] In the figure: 1. Power supply module; 2. Monitoring host; 3. Remote terminal unit; 4. Cloud platform system; 5. Main cable current and temperature monitoring sensor; 6. Cable grounding current monitoring sensor. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0016] Next, the technical solutions in the embodiments of the present utility model will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present utility model. Obviously, the described embodiments are only a part of the embodiments of the present utility model, rather than all the embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative work shall fall within the protection scope of the present utility model.

[0017] In order to solve the technical problem that the existing patents analyze by taking photos of cables by inspectors during use, so it is impossible to quickly understand the cable grounding faults and problems cannot be discovered in time, which brings great hidden dangers to the reliability of the power supply system and cannot meet the requirements of modern power grid operation, please refer to Figure 1 - Figure 2 This embodiment provides the following technical solutions:

[0018] A high-voltage cable grounding current warning device includes a monitoring host 2. The monitoring host 2 communicates with a remote terminal 3 through a wireless transmission module. The monitoring host 2 is equipped with a frequency division filtering function, which can collect and analyze different frequency signals. After collecting the cable status information, it locally analyzes its waveform and compares it with the characteristic waveform spectrum. When the alarm condition is met, it alarms and uploads the information. The uploaded information includes alarm information and waveform information at the alarm moment, etc. The monitoring host 2 is an ARM+FPGA platform. Inside the monitoring host 2, there is a high-order FIR filter, which can effectively filter out interference signals. The single-channel sampling rate can reach up to 100 MHz at most, meeting the sampling requirements of high-frequency pulse current sensors. High-speed sampling through the FPGA can increase the sampling rate, maintain the waveform integrity, and avoid waveform distortion during the detection process. ARM+FPGA real-time data analysis improves the accuracy of judgment. And inside the monitoring host 2, there are an information upload module and a time calibration module. The wireless transmission module includes RS485, Ethernet, optical fiber, and NB-IOT / Lora Internet of Things communication. The monitoring host 2 can upload information to the cloud platform system 4 through the wireless transmission module. The background is a third-party software background such as an integrated automation system or an auxiliary monitoring system. The monitoring host 2 includes a time calibration function. It can receive the 10-code time calibration signal sent by other systems through the RS485 protocol, or receive the Beidou NTP server time synchronization signal through the local area network, ensuring that the time of all devices in the area is accurate, facilitating cable health status analysis and fault location. The monitoring host 2 simultaneously monitors the operating status of multiple cables and conducts a horizontal comparison analysis of a group of cables. The cloud platform system 4 is a cloud management system built on Alibaba Cloud, Tencent Cloud, or other platforms. The monitoring host 2 can be connected to a maximum of 6 sets of main cable current and temperature monitoring sensors 5 and cable grounding current monitoring sensors 6. After analysis and calculation, the monitoring host 2 conducts monitoring and early warning and uploads the early warning information to the cloud platform system 4. After the monitoring host 2 uploads the cable early warning information to the cloud platform system 4, the operation and maintenance personnel can log in to the corresponding account on the cloud platform system 4 for management, query, and other work. The cloud platform system 4 has functions such as data collection, in-depth analysis, management, information integration, and message notification. It can judge cable faults and give early warnings through the cloud platform system, improving the accuracy and timeliness of early warnings. The power supply module 1 includes a solar panel and a solar controller. The solar panel is connected to the solar controller. The remote terminal 3 communicates with the cloud platform system 4. The monitoring host 2 communicates with the sensors respectively. The sensors include the main cable current and temperature monitoring sensors 5 and the cable grounding current monitoring sensors 6. The main cable current and temperature monitoring sensors 5 and the cable grounding current monitoring sensors 6 are both connected to the monitoring host 2 through multi-core cables, transmitting the monitored signals to the monitoring host 2 for analysis and processing. The monitoring host 2 is connected to power supplies of various voltage levels through the power supply module 1.

[0019] The main cable current and temperature monitoring sensor 5 includes a sensor housing, a main cable current measurement transformer core, a temperature measurement sensor, a water immersion sensor, and a vibration sensor. The main cable current measurement transformer core, the temperature measurement sensor, the water immersion sensor, and the vibration sensor are all arranged inside the sensor housing. The current measurement transformer core is a toroidal core made of nanocrystalline material, which is used to measure the operating current of the main cable and the temperature of the joint. The main cable current and temperature monitoring sensor 5 adopts a double-coil structure. The double-coil structure includes a power-taking coil and a measurement coil. The power-taking coil is responsible for obtaining electrical energy from the current flowing through the main cable, and the measurement coil is responsible for collecting the working current from the current of the main cable joint. At the same time, a high-precision, low-power, and fast-response linear analog temperature sensor is selected to collect the temperature data of the main cable joint. The main cable current and temperature monitoring sensor 5 uses a butterfly magnet to collect magnetic lines of force. According to the electromagnetic induction law, it powers the temperature sensor. The two ends of the butterfly magnet have a large area, forming an efficient magnetic flux collector, which can more effectively collect magnetic lines of force and guide the magnetic lines of force into the core column, which can strengthen the magnetic induction intensity of the core column part, thereby increasing the induced voltage. The iron core and the coil are installed close to the surface of the main cable. Figure 2 Among them, BM represents the butterfly magnet, TS represents the temperature sensor, DP represents data processing, EH represents the energy-taking circuit, CM represents the communication module, and A / D represents the converter.

[0020] The cable grounding current monitoring sensor 6 is a low-power micro sensor. By reducing the Hs of the iron core, the optimal excitation current is decreased. The cable grounding current monitoring sensor 6 internally includes a circulating current monitoring sensor, a partial discharge monitoring sensor, a voltage induction coil, and a current measurement coil. Inside the cable grounding current monitoring sensor 6, multiple current measurement coils and one excitation coil are integrated, and the excitation coil and the induction coil are arranged alternately to reduce the leakage magnetic flux. The measurement coil can measure the power frequency current value of the cable grounding wire to reflect the cable circulating current information and the high-frequency current signal on the grounding wire to reflect the cable partial discharge information. At the same time, the excitation coil can emit a current pulse signal of a specific frequency and perform measurements to finally calculate the grounding resistance value of the cable grounding wire. By calculating the excitation current through finite element simulation and modifying the coil winding method, its overall performance is effectively improved and the working power consumption is reduced. The cable grounding current monitoring sensor 6 is used to measure the circulating current information, high-frequency pulse current information, or partial discharge information on the cable armor layer or shield layer grounding wire, and induces a voltage of a specific frequency on the grounding wire. By measuring the current flowing through the grounding wire, the grounding resistance value is calculated, and the monitored signal is transmitted to the monitoring host 2 for analysis and processing. The monitoring host 2 can induce an electromotive force E and a current I in the measured circuit through the excitation coil, and calculate the cable grounding resistance value by measuring these two parameters. By analyzing the grounding resistance value, it can be determined whether the cable grounding is good and whether there is a situation of multiple grounding points. The circulating current monitoring sensor includes a sensor housing, a circulating current measurement and grounding resistance current measurement magnetic core, a grounding resistance voltage induction magnetic core, and a high-frequency pulse current transformer magnetic core.

[0021] During use, the main cable current and temperature monitoring sensor 5 obtains electrical energy from the current flowing through the main cable and collects the working current from the current of the main cable joint, and at the same time collects the temperature data of the main cable joint. The cable grounding current monitoring sensor 6 measures the circulating current information, high-frequency pulse current information, or partial discharge information on the cable armor layer or shield layer grounding wire, and induces a voltage of a specific frequency on the grounding wire. By measuring the current flowing through the grounding wire, the grounding resistance value is calculated, and the monitored signal is transmitted to the monitoring host 2 for analysis and processing. The monitoring host 2 induces an electromotive force E and a current I in the measured circuit through the excitation coil, and calculates the cable grounding resistance value by measuring these two parameters. By analyzing the grounding resistance value, it can be determined whether the cable grounding is good and whether there is a situation of multiple grounding points. After the monitoring host 2 uploads the electrical energy on the current flowing through the main cable, the working current collected from the main cable joint current, the temperature data of the main cable joint, and whether there is a situation of multiple grounding points to the cloud platform system 4, the cloud platform system 4 determines whether there is a grounding fault in the cable. If so, it gives an early warning.

[0022] In summary, for this high-voltage cable grounding current warning device, the main cable current and temperature monitoring sensor 5 obtains electric energy from the current flowing through the main cable and collects the working current from the current of the main cable joint. At the same time, it collects the temperature data of the main cable joint. The cable grounding current monitoring sensor 6 detects and analyzes whether the cable grounding is good and whether there is a multi-point grounding situation. The monitoring host 2 collects the data of the main cable current and temperature monitoring sensor 5 and the cable grounding current monitoring sensor 6, locally analyzes its waveform, and compares it with the characteristic waveform spectrum. When the alarm condition is met, it alarms and uploads the data. The cloud platform system 4 collects, deeply analyzes, and integrates the information, judges the cable fault, and gives an early warning, improving the accuracy and timeliness of the early warning, eliminating the need for manual inspection, reducing manpower and material resources, and saving costs.

[0023] It should be noted that in this article, relational terms such as first and second are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any actual relationship or order between these entities or operations. Moreover, the term "comprising", "including" or any other variant thereof is intended to cover non-exclusive inclusion, so that a process, method, article or device comprising a series of elements of a high-voltage cable grounding current warning device not only includes those elements, but also includes other elements not expressly listed, or also includes elements inherent to such process, method, article or device.

[0024] Although the embodiments of the present invention have been shown and described, those of ordinary skill in the art can understand that various changes, modifications, substitutions, and variations can be made to these embodiments without departing from the principle and spirit of the present invention. The scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A high-voltage cable grounding current warning device, comprising a monitoring host (2), characterized in that: The monitoring host (2) communicates with the remote terminal (3) through a wireless transmission module. The remote terminal (3) communicates with the cloud platform system (4). The monitoring host (2) communicates with sensors respectively. The sensors include the main cable current and temperature monitoring sensor (5) and the cable grounding current monitoring sensor (6). Both the main cable current and temperature monitoring sensor (5) and the cable grounding current monitoring sensor (6) are connected to the monitoring host (2) through a multi-core cable. The monitoring host (2) is connected to power supplies of various voltage levels through the power supply module (1).

2. The high-voltage cable grounding current warning device according to claim 1, characterized in that: The main cable current and temperature monitoring sensor (5) includes a sensor housing, a main cable current measurement transformer core, a temperature measurement sensor, a water immersion sensor, and a vibration sensor. The main cable current measurement transformer core, the temperature measurement sensor, the water immersion sensor, and the vibration sensor are all arranged inside the sensor housing. The current measurement transformer core is a ring-shaped core made of nanocrystalline material.

3. The ground current warning device for high-voltage cables according to claim 1, characterized in that: The cable grounding current monitoring sensor (6) is a low-power micro sensor. Inside the cable grounding current monitoring sensor (6), there are a circulating current monitoring sensor, a partial discharge monitoring sensor, a voltage induction coil, and a current measurement coil. Inside the cable grounding current monitoring sensor (6), multiple current measurement coils and one excitation coil are integrated, and the excitation coil and the induction coil are arranged alternately.

4. A high-voltage cable grounding current warning device according to claim 3, characterized in that: The circulating current monitoring sensor includes a sensor housing, a circulating current and grounding resistance current measurement core, a grounding resistance voltage induction core, and a high-frequency pulse current transformer core.

5. The high-voltage cable grounding current warning device according to claim 1, characterized in that: The monitoring host (2) is an ARM+FPGA platform. Inside the monitoring host (2), there is a high-order FIR filter, and there are also an information uploading module and a time calibration module inside the monitoring host (2).

6. The warning device for grounding current of high-voltage cable according to claim 1, wherein: The cloud platform system (4) is a cloud management system built on Alibaba Cloud, Tencent Cloud, or other platforms.

7. The high-voltage cable grounding current warning device according to claim 1, characterized in that: The power supply module (1) includes a solar panel and a solar controller. The solar panel is connected to the solar controller.

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