Automatic monitoring and early warning system for sag state of overhead transmission line OPGW (Optical Fiber Composite Overhead Ground Wire) based on distributed sensing optical cable

Abstract

The invention discloses an overhead transmission line OPGW sag state automatic monitoring and early warning system based on a distributed sensing optical cable, and the system comprises a novel quasi-distributed WDM-FBG sensing optical cable which is internally provided with an FBG sensor and is used for periodically collecting wavelength data; the at least one field autonomous monitoring unit is used for storing and primarily processing the wavelength data and sending a processing result to the remote server; and the remote server is used for fitting the sag state of the overhead transmission line according to the primary processing result of the wavelength data and providing early warning information.

Description

Technical Field

[0001] This invention relates to the field of power system monitoring technology, specifically to an automated monitoring and early warning system for the sag status of overhead transmission lines (OPGW) based on distributed sensing optical cables. Background Technology

[0002] Line sag is one of the key parameters reflecting the condition of overhead power transmission lines (OPGW). Excessively low sag may lead to insufficient safe distances to the ground or objects, causing discharges or even tripping accidents. Furthermore, abnormal conditions such as line icing and galloping also seriously threaten line safety. Therefore, real-time and accurate online monitoring of the dynamic sag and condition of overhead power transmission lines is of great significance.

[0003] Currently, methods for monitoring the sag of overhead transmission lines mainly include manual inspection, total station measurement, tilt sensors, tension sensors, video image monitoring, and GPS-based monitoring. Each of these methods has its limitations. For example, manual inspection is inefficient and lacks real-time performance; total station measurement is greatly affected by weather and cannot provide continuous monitoring; traditional point sensors (such as tilt and tension sensors) can monitor online, but they typically only reflect the condition near the installation point, making it difficult to obtain complete sag information for the entire line. Furthermore, the installation, power supply, communication, and maintenance of numerous point sensors are costly and complex.

[0004] FBGs are used for temperature and strain measurements. However, existing FBG-based monitoring solutions typically have the following problems: 1) Traditional FBG sensor array optical cables are not adequately designed, packaged, and integrated with the line. Their reliability in harsh outdoor environments with high voltage, strong vibration, and large temperature differences needs to be improved. 2) Complex signal demodulation, data processing, and power supply communication equipment usually still needs to be deployed at the tower end. On-site construction is complicated, maintenance costs are high, and it is difficult to achieve low-cost deployment of large-scale lines. Summary of the Invention

[0005] To overcome the problems of incomplete monitoring coverage, complex on-site deployment, power supply difficulties, high maintenance costs, and difficulty in achieving long-term autonomous operation in existing overhead transmission line sag and condition monitoring technologies, this invention provides an automated monitoring and early warning system for the sag status of overhead transmission lines' OPGW based on distributed sensing optical cables. By providing a novel quasi-distributed FBG sensing optical cable and designing an on-site autonomous monitoring unit to achieve on-site self-power supply and autonomous data acquisition and transmission capabilities, it possesses the advantages of quasi-distributed, low-cost, easy-to-deploy, and long-term autonomous operation, realizing accurate, reliable, and low-cost online monitoring of the sag status of overhead transmission lines' OPGW.

[0006] According to one aspect of the present invention, an automated monitoring and early warning system for the sag status of an overhead transmission line (OPGW) based on distributed sensing optical cables is provided, comprising:

[0007] A novel quasi-distributed WDM-FBG (wavelength division multiplexing-fiber Bragg grating) sensing optical cable is equipped with an internal FBG (fiber Bragg grating) sensor to periodically collect wavelength data.

[0008] At least one on-site autonomous monitoring unit is used to store and preliminarily process wavelength data and send the processing results to a remote server;

[0009] A remote server fits the sag status of overhead transmission lines based on the preliminary processing results of wavelength data and provides early warning information.

[0010] As a further implementation scheme, the new quasi-distributed WDM-FBG sensing optical cable is obtained by optimizing the structure of the quasi-distributed WDM-FBG sensing optical cable. The optimization methods include: using ultra-weak reflectivity fiber gratings for single optical fibers, multi-core fiber design, special coating layer, non-invasive clamps, and high-temperature resistant packaging.

[0011] As a further implementation scheme, the new quasi-distributed WDM-FBG sensing optical cable is laid on the load-bearing cable of the overhead transmission line, with the line span set. Within each span, FBG sensors are connected in series along the length direction inside the optical cable at a preset distance, and each FBG sensor corresponds to a different center reflection wavelength.

[0012] As a further implementation scheme, the on-site autonomous monitoring unit is installed on the tower of the overhead transmission line. It is a highly integrated box unit, which includes: a solar self-powered module, a WDM (wavelength division multiplexing) wavelength demodulation module, an IoT wireless communication module, and a data processing and storage module. The solar self-powered module powers the on-site autonomous monitoring unit. The data processing and storage module provides data caching and control functions for the WDM wavelength demodulation module and the IoT wireless communication module, including: controlling the WDM wavelength demodulation module to receive and preliminarily process wavelength data collected by the FBG sensor in the new quasi-distributed WDM-FBG sensing optical cable and package it; controlling the IoT wireless communication module to send the packaged data to a remote server; the solar panel collects solar energy and converts it into electrical energy; the energy storage battery stores electrical energy and powers the on-site autonomous monitoring unit; the power management unit integrates an MPPT controller to maximize the solar energy collection efficiency of the solar panel and manage the charging and discharging process of the energy storage battery to maintain the long-term operation of the system.

[0013] As a further implementation scheme, the solar self-powered module includes a solar panel, a power management unit, and an energy storage battery.

[0014] As a further implementation, the data processing and storage module includes a memory and a controller, wherein the controller is selected as a low-power microcontroller or embedded processor, which controls the operation of the on-site autonomous monitoring unit, and the operation includes:

[0015] The WDM demodulation module is controlled to periodically acquire wavelength data, perform preliminary processing on the wavelength data, and then perform basic temperature and strain decoupling calculations.

[0016] The results of basic temperature and strain decoupling calculations are packaged and the memory is controlled to provide data caching functionality.

[0017] The control IoT wireless communication module sends packaged data to a remote server.

[0018] As a further implementation scheme, the remote server is a server cluster, including:

[0019] The algorithm engine runs algorithms based on the preliminary processing results of wavelength data, including: temperature compensation algorithm and sag reconstruction algorithm based on multi-point FBG strain and temperature data;

[0020] The user interface / visualization platform displays the real-time sag profile and early warning information of the line to maintenance personnel.

[0021] According to one aspect of the present invention, an automated monitoring and early warning method for the sag status of an overhead transmission line OPGW based on distributed sensing optical cables is provided, comprising:

[0022] The on-site autonomous monitoring unit emits broadband light to the new quasi-distributed WDM-FBG sensing optical cable according to the preset sampling frequency, and receives the raw wavelength data reflected back from all FBG sensors.

[0023] The on-site autonomous monitoring unit performs preliminary processing on the collected raw wavelength data and packages the preliminary processing results to send to the remote server;

[0024] The remote server fits and solves the real-time sag value of the autonomous overhead transmission line based on the received preliminary processing results, and presets a sag safety threshold. When the real-time sag value exceeds the sag safety threshold, an alarm signal is generated.

[0025] As a further implementation plan, the on-site autonomous monitoring unit includes a solar self-powered module, a WDM wavelength demodulation module, an IoT wireless communication module, and a data processing and storage module. The specific working process is as follows:

[0026] The data processing and storage module controls the WDM wavelength demodulation module to emit broadband light to the sensing optical cable according to the preset sampling frequency, and receives and demodulates the center wavelength reflected back by all FBG sensors. Then, the processed data is packaged, stored, and transmitted to a remote server through the Internet of Things wireless communication module. The power for the entire process is provided by the solar self-powered module.

[0027] As a further implementation scheme, the remote server is equipped with an algorithm engine. After receiving the data, it first performs accurate temperature compensation through a temperature compensation algorithm, and then constructs a sag reconstruction model based on a sag reconstruction algorithm based on multi-point FBG strain and temperature data. The sag equation of the autonomous overhead transmission line within the span is obtained through numerical solution, thereby obtaining the real-time sag value of the lowest point or the real-time sag value of any point.

[0028] Compared with the prior art, the beneficial effects of the present invention are as follows: The present invention provides a novel quasi-distributed FBG sensing optical cable to enhance its long-term stability and anti-interference ability in harsh environments, and designs an on-site autonomous monitoring unit to realize on-site self-power supply and autonomous data acquisition and transmission capabilities, which greatly simplifies the workload and complexity of on-site installation and deployment. It has the advantages of quasi-distributed, low cost, easy deployment, and long-term autonomous operation, and realizes accurate, reliable and low-cost online monitoring of the sag status of overhead transmission line OPGW. Attached Figure Description

[0029] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the accompanying drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the accompanying drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0030] Figure 1 This is a schematic diagram of the overall architecture of an automated monitoring and early warning system for OPGW sag status of overhead transmission lines based on distributed sensing optical cables, provided by an embodiment of the present invention: 10-New type of quasi-distributed WDM-FBG sensing optical cable, 11-FBG sensing point, 12-Non-invasive clamp / installation component, 20-Field autonomous monitoring unit, 30-Remote server, 32-Algorithm engine, 33-User interface / visualization platform;

[0031] Figure 2 This is a block diagram of the internal structure of the on-site autonomous monitoring unit in this embodiment of the invention: 21-Solar self-powered module, 211-Solar panel, 212-Power management unit, 213-Energy storage battery, 22-WDM wavelength demodulation module, 23-IoT wireless communication module, 24-Data processing and storage module;

[0032] Figure 3This is a schematic diagram of the monitoring process of an automated monitoring and early warning system for the sag status of an overhead transmission line OPGW based on a distributed sensing optical cable, provided in an embodiment of the present invention.

[0033] Figure 4 This is a flowchart illustrating a method for monitoring the dynamic sag of an overhead transmission line according to an embodiment of the present invention. Detailed Implementation

[0034] It should be noted that:

[0035] The terms “comprising” and “having”, and any variations thereof, in the specification, claims, and accompanying drawings of this invention are intended to cover a non-exclusive inclusion, such as a process, method, system, product, or apparatus that includes a series of steps or units, not necessarily limited to those explicitly listed, but may include other steps or units not explicitly listed or inherent to such processes, methods, products, or apparatus.

[0036] The block diagrams shown in the accompanying drawings are merely functional entities and do not necessarily correspond to physically independent entities. That is, these functional entities can be implemented in software, in one or more hardware modules or integrated circuits, or in different network and / or processor devices and / or microcontroller devices. The flowcharts shown in the accompanying drawings are merely illustrative and do not necessarily include all content and operations / steps, nor do they necessarily have to be performed in the described order. For example, some operations / steps can be decomposed, while others can be combined or partially combined; therefore, the actual execution order may change depending on the specific circumstances.

[0037] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention. In addition, the technical features of the various embodiments or individual embodiments provided by the present invention can be arbitrarily combined to form new technical solutions. Such combinations are not bound by the order of steps and / or structural composition patterns, but must be based on the ability of those skilled in the art to implement them. When the combination of technical solutions is contradictory or cannot be implemented, it should be considered that such a combination of technical solutions does not exist and is not within the scope of protection claimed by the present invention.

[0038] An automated monitoring and early warning system for the sag condition of overhead power transmission lines (OPGW) based on distributed sensing optical cables includes:

[0039] A novel quasi-distributed WDM-FBG (wavelength division multiplexing-fiber Bragg grating) sensing optical cable (10) is equipped with an FBG (fiber Bragg grating) sensor (11) inside, which periodically collects wavelength data.

[0040] At least one on-site autonomous monitoring unit (20) is used to store and pre-process wavelength data and send the processing results to a remote server;

[0041] The remote server (30) fits the sag state of the overhead transmission line based on the preliminary processing results of the wavelength data and provides early warning information.

[0042] Furthermore, the novel quasi-distributed WDM-FBG sensing optical cable is obtained by optimizing the structure of the quasi-distributed WDM-FBG sensing optical cable.

[0043] Quasi-distributed WDM-FBG sensing optical cable integrates multiple FBG units on a single optical fiber, and each FBG unit reflects light of a specific wavelength;

[0044] The optimization methods include: using ultra-weak reflectivity fiber gratings for single optical fibers, multi-core fiber design, special coating layer, non-invasive clamps (12) and high temperature resistant packaging.

[0045] Specifically, using ultra-weak reflectivity fiber gratings (UWFBG) enables a higher density of sensing points and long-distance monitoring per unit fiber length. Compared to ordinary FBGs, it can increase capacity by thousands of times, achieving a monitoring density far exceeding that of quasi-distributed sensing optical cables, approaching that of fully distributed sensing optical cables. At the same time, it maintains extremely low optical transmission loss. Combined with a data acquisition and processing system, it can acquire massive amounts of strain and temperature data continuously distributed along the fiber path. With the help of an algorithm engine, it can achieve higher precision and longer-distance sag measurement.

[0046] Specifically, a special coating is used to enhance the strain transfer efficiency and wear resistance of the FBG. In this embodiment, an enhanced polyurethane sheath is used.

[0047] Specifically, FBG is integrated onto a substrate with a specific coefficient of thermal expansion to assist in temperature compensation. In this embodiment, high-temperature resistant encapsulation is used, and it is reinforced with high-strength carbon fiber.

[0048] Specifically, a non-invasive clamp (12) that allows for quick installation and causes minimal damage to the OPGW ensures that the sensing optical cable maintains a stable relative position and appropriate prestress with the OPGW. In this embodiment, the clamp material can be weather-resistant engineering plastic or aluminum alloy.

[0049] Specifically, using multi-core optical fiber design for redundancy backup and statistical processing can improve data reliability.

[0050] Specifically, using ultra-weak reflectivity fiber gratings (UWFBG) enables a higher density of sensing points and long-distance monitoring per unit fiber length. Compared to ordinary FBGs, it can increase capacity by thousands of times, achieving a monitoring density far exceeding that of quasi-distributed sensing optical cables, approaching that of fully distributed sensing optical cables. At the same time, it maintains extremely low optical transmission loss. Combined with a data acquisition and processing system, it can acquire massive amounts of strain and temperature data continuously distributed along the fiber path. With the help of an algorithm engine, it can achieve higher precision and longer-distance sag measurement.

[0051] Furthermore, the new quasi-distributed WDM-FBG sensing optical cable is laid on the load-bearing cable of the overhead transmission line, with the line span set. Within each span, FBG sensors are connected in series along the length direction inside the optical cable at a preset distance, and each FBG sensor corresponds to a different center reflection wavelength.

[0052] Specifically, the novel quasi-distributed WDM-FBG sensing optical cable is designed for laying along overhead transmission lines (such as the OPGW itself or parallel-installed load-bearing cables). Multiple FBG sensors with different center reflection wavelengths are connected in series along the length of the optical cable (5-20 per span). The spacing between these FBG sensors is optimized according to the monitoring accuracy requirements and the line span; in this embodiment, it is exemplaryly set to 0.5 meters to 2 meters.

[0053] In a preferred embodiment, multiple FBG sensors are configured with different center reflection wavelengths to measure different physical quantities.

[0054] Furthermore, the on-site autonomous monitoring unit is installed on the tower of the overhead transmission line. It is a highly integrated box unit, which includes: a solar self-powered module (21), a WDM wavelength demodulation module (22), an Internet of Things wireless communication module (23), and a data processing and storage module (24).

[0055] Specifically, the WDM wavelength demodulation module employs high-speed, high-precision wavelength demodulation technology (such as scanning laser or tunable filter-based technology) to simultaneously demodulate the reflected wavelengths of all FBG sensors on the sensing optical cable. The wavelength demodulation accuracy is better than 1 pm, and the demodulation rate can reach 1 kHz to capture dynamic events.

[0056] Specifically, the Internet of Things (IoT) wireless communication module uses low-power wide-area network (LPWAN) technologies, such as NB-IoT or LoRaWAN modules, or 4G / 5G modules depending on coverage conditions. It is responsible for wirelessly transmitting the collected and processed data to a remote server in a low-power manner. The communication protocol can be MQTT or CoAP.

[0057] Specifically, the data processing and storage module typically includes a low-power microcontroller (MCU) or embedded processor (such as the ARM Cortex-M series) running an embedded operating system. It controls the WDM demodulation module to perform periodic data acquisition, performs preliminary processing on the raw wavelength data (such as filtering and peak wavelength extraction), performs basic temperature / strain decoupling calculations (if some compensation is done locally), packages the data, and sends it via the IoT module. It also includes a certain capacity of non-volatile memory (such as an SD card) for data caching to prevent data loss during network interruptions. This module can implement edge computing functions, such as performing data compression and anomaly detection.

[0058] Furthermore, the solar self-powered module includes a solar panel (211), a power management unit (212), and an energy storage battery (213).

[0059] Specifically, in this embodiment of the invention, the solar self-powered module consists of one or more high-efficiency monocrystalline silicon solar panels connected to an intelligent power management unit. This unit integrates an MPPT controller to maximize solar energy collection efficiency and manages the charging and discharging process of a high- and low-temperature resistant, long-life lithium battery pack, ensuring basic system operation even during continuous cloudy or rainy days. For example, the parameter settings are as follows: the high-efficiency monocrystalline silicon solar panel is selected with a power of not less than 50W, and the lithium battery pack is set with a capacity ≥20Ah and an operating temperature of -40℃ to +70℃.

[0060] Furthermore, the data processing and storage module includes a memory and a controller. The controller is a low-power microcontroller or embedded processor that controls the embedded operating system of the on-site autonomous monitoring unit. The system operation includes:

[0061] The WDM demodulation module is controlled to periodically acquire wavelength data, perform preliminary processing on the wavelength data, and then perform basic temperature and strain decoupling calculations.

[0062] The results of basic temperature and strain decoupling calculations are packaged and the memory is controlled to provide data caching functionality.

[0063] The control IoT wireless communication module sends packaged data to a remote server.

[0064] Furthermore, the remote server is a server cluster, including:

[0065] The algorithm engine (32) runs algorithms based on the preliminary processing results of wavelength data, including: temperature compensation algorithm and sag reconstruction algorithm based on multi-point FBG strain and temperature data;

[0066] User interface / visualization platform (33) displays the real-time sag profile and early warning information of the line to maintenance personnel via the Web or a dedicated client.

[0067] Specifically, the algorithm engine is the core processing unit. It runs complex algorithms, including: (a) sophisticated temperature compensation algorithms (which may combine independent temperature sensor data or utilize the characteristics of the FBG itself); (b) sag reconstruction algorithms based on multi-point FBG strain and temperature data, for example, dividing the track span into multiple segments, applying the catenary equation to each segment, and fitting the sag curve of the entire span using FBG measurement points as constraints; and (c) track condition identification algorithms based on time-series data analysis, such as using FFT, wavelet transform, or machine learning (e.g., LSTM) to identify the frequency and amplitude of track galloping characteristics, or determining the type and thickness of icing based on strain and temperature change patterns.

[0068] As a preferred implementation, the remote server also includes a database that stores historical data, line basic information, equipment management information, etc., of all received field monitoring units. Based on this, the algorithm engine sets up a line status identification algorithm based on time-series data analysis. In addition to displaying the real-time sag profile and early warning information of the overhead transmission line to maintenance personnel through the Web or a dedicated client, the user interface / visualization platform also provides historical data curves and status assessment results, and may integrate GIS map display.

[0069] The system embodiments described above are merely illustrative. The units described as separate components may or may not be physically separate, and the components shown as units may or may not be physical units, located in one place, or distributed across multiple network units. The purpose of this embodiment is achieved by selecting some or all of the modules according to actual needs. Those skilled in the art will understand and implement this without any inventive effort.

[0070] The system embodiment provided by this invention is used to implement an automated monitoring and early warning method for the sag status of overhead transmission lines (OPGW) based on distributed sensing optical cables, comprising:

[0071] The on-site autonomous monitoring unit emits broadband light to the new quasi-distributed WDM-FBG sensing optical cable according to the preset sampling frequency, and receives the raw wavelength data reflected back from all FBG sensors.

[0072] The on-site autonomous monitoring unit performs preliminary processing on the collected raw wavelength data and packages the preliminary processing results to send to the remote server;

[0073] The remote server fits and solves the real-time sag value of the autonomous overhead transmission line based on the received preliminary processing results, and presets a sag safety threshold. When the real-time sag value exceeds the sag safety threshold, an alarm signal is generated.

[0074] As a further implementation plan, the on-site autonomous monitoring unit includes a solar self-powered module, a WDM wavelength demodulation module, an IoT wireless communication module, and a data processing and storage module. The specific working process is as follows:

[0075] The data processing and storage module controls the WDM wavelength demodulation module to emit broadband light to the sensing optical cable according to the preset sampling frequency, and receives and demodulates the center wavelength reflected back by all FBG sensors. Then, the processed data is packaged, stored, and transmitted to a remote server through the Internet of Things wireless communication module. The power for the entire process is provided by the solar self-powered module.

[0076] As a further implementation scheme, the remote server is equipped with an algorithm engine. After receiving the data, it first performs accurate temperature compensation through a temperature compensation algorithm, and then constructs a sag reconstruction model based on a sag reconstruction algorithm based on multi-point FBG strain and temperature data. The sag equation of the autonomous overhead transmission line within the span is obtained through numerical solution, thereby obtaining the real-time sag value of the lowest point or the real-time sag value of any point.

[0077] It should be noted that the system embodiments provided by this invention, in addition to implementing the methods in the above system embodiments, are also used to implement the methods in other method embodiments provided by this invention. The difference lies only in setting corresponding functional modules, and their principles are basically the same as those in the above system embodiments provided by this invention. As long as those skilled in the art, based on the above system embodiments and referring to the specific technical solutions in other method embodiments, obtain corresponding technical means and technical solutions constituted by these technical means by combining technical features, and improve the equipment in the above system embodiments while ensuring the practicality of the technical solutions, they can obtain corresponding system-like embodiments for implementing the methods in other method-like embodiments. For example:

[0078] A method for monitoring dynamic sag of overhead transmission lines, comprising the following steps: visualization.

[0079] S1. Automatic acquisition of FBG wavelength data. The on-site autonomous monitoring unit controls the WDM wavelength demodulation module to emit broadband light to the sensing optical cable according to a preset sampling frequency (e.g., once every 10 minutes during static monitoring, increasing to 1Hz or higher when a dynamic event is triggered), and receives and demodulates the center wavelength λ reflected back from all FBG sensors. B,i , where λ B Indicates wavelength, and i is the number of the FBG sensor.

[0080] S2. On-site processing and autonomous wireless transmission. The data processing and storage module processes the acquired raw wavelength data λ. B,i The data is then processed. If the field unit integrates a separate temperature sensor (e.g., a Pt100 or digital temperature sensor mounted on the outer wall of the enclosure), temperature data T is acquired simultaneously. The module can perform data validity checks and calculate the wavelength change Δλ. B,i Then the processed data (such as Δλ) B,i and T) or raw data λ B,i The packaged data is autonomously transmitted to a remote server in low-power mode via an IoT wireless communication module using NB-IoT or 4G / 5G networks. The entire process is powered by a self-contained solar-powered module.

[0081] S3. Remote Temperature Compensation and Sag Reconstruction. After receiving the data, the algorithm engine on the remote server first performs precise temperature compensation. This is due to the wavelength change Δλ of the FBG. B Simultaneously affected by strain ϵ and temperature change ΔT (Δλ) B =K ϵ ϵ+K T ΔT, where K ϵ and K T These are the strain and temperature sensitivity coefficients, respectively, and decoupling is required. There are several compensation methods, such as: (a) using the temperature T transmitted by the field unit as an approximate global temperature for compensation; (b) if the sensing optical cable contains a reference FBG that is only sensitive to temperature, then the temperature information can be directly obtained using its wavelength change; (c) if there is no independent temperature measurement, a temperature estimation model based on historical data, meteorological data, or line load data can be established; (d) for dynamic events (such as galloping), it can be assumed that temperature changes are negligible in a short period, and the changes caused by strain are mainly analyzed. The strain ϵ at each FBG measurement point is obtained. i Then, the algorithm engine uses the sag reconstruction model. For example, it treats the span as multiple catenary segments and utilizes the strain ε at each FBG point. i The sag equation y(x) of the entire span is obtained by numerical solution (such as Newton's iteration method or finite element method) and the line parameters (span, elevation difference, line weight, elastic modulus, etc.), which reflect the tension or elongation at that point. Then, the sag value at the lowest point or the sag at any point is obtained.

[0082] S4. Status Assessment and Early Warning. The remote server compares the calculated real-time sag value with a preset safety threshold. If the sag is below the safe distance, an early warning is triggered, notifying maintenance personnel via the user interface, SMS, or app push notifications. Simultaneously, the server continuously analyzes time-series data on sag, strain, and temperature, runs status recognition algorithms to determine if abnormal conditions such as line galloping or icing exist, and performs assessments and issues alarms.

[0083] Those skilled in the art will understand that embodiments of the present invention can be provided as methods, systems, or computer program products. Therefore, the present invention can take the form of a completely hardware embodiment, a completely software embodiment, or an embodiment combining software and hardware aspects. Furthermore, the present 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.

[0084] This invention is described with reference to flowchart illustrations and / or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of the invention. It will be understood that each block of the flowchart illustrations and / or block diagrams, and combinations of blocks in the flowchart illustrations and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, special-purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, generate instructions for implementing the flowchart illustrations and / or block diagrams. Figure 1 One or more processes and / or boxes Figure 1 A device that provides the functions specified in one or more boxes.

[0085] These computer program instructions may also be stored in a computer-readable storage medium that can direct a computer or other programmable data processing device to function in a particular manner, such that the instructions stored in the computer-readable storage medium produce an article of manufacture including instruction means, which are implemented in a process Figure 1 One or more processes and / or boxes Figure 1 The function specified in one or more boxes.

[0086] These computer program instructions may also be loaded onto a computer or other programmable data processing equipment to cause a series of operational steps to be performed on the computer or other programmable equipment to produce a computer-implemented process, thereby providing instructions that execute on the computer or other programmable equipment for implementing the process. Figure 1 One or more processes and / or boxes Figure 1 The steps of the function specified in one or more boxes.

[0087] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features therein; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the technical solutions of the embodiments of the present invention.

Claims

1. An automated monitoring and early warning system for the sag status of overhead power transmission lines (OPGW) based on distributed sensing optical cables, characterized in that, include: The new quasi-distributed WDM-FBG sensing optical cable has multiple FBG sensors inside, which periodically collect wavelength data. At least one on-site autonomous monitoring unit is used to store and preliminarily process wavelength data and send the processing results to a remote server; A remote server fits the sag status of overhead transmission lines based on the preliminary processing results of wavelength data and provides early warning information.

2. The automated monitoring and early warning system for OPGW sag status of overhead transmission lines based on distributed sensing optical cables as described in claim 1, characterized in that, The novel quasi-distributed WDM-FBG sensing optical cable is obtained by optimizing the structure of the quasi-distributed WDM-FBG sensing optical cable. Quasi-distributed WDM-FBG sensing optical cable integrates multiple FBG units on a single optical fiber, and each FBG unit reflects light of a specific wavelength; Optimization methods include: using ultra-low reflectivity fiber Bragg gratings for single optical fibers, multi-core fiber design, special coatings, non-invasive clamps, and high-temperature resistant packaging.

3. The automated monitoring and early warning system for OPGW sag status of overhead transmission lines based on distributed sensing optical cables as described in claim 1, characterized in that, The novel quasi-distributed WDM-FBG sensing optical cable is laid on the load-bearing cable of an overhead power transmission line. The line span is set, and multiple FBG sensors are connected in series along the length direction inside the optical cable at a preset distance within each span. Each FBG sensor corresponds to a different center reflection wavelength.

4. The automated monitoring and early warning system for OPGW sag status of overhead transmission lines based on distributed sensing optical cables as described in claim 1, characterized in that, The on-site autonomous monitoring unit is installed on the tower of the overhead transmission line and is a highly integrated box unit. The box includes: a solar self-powered module, a WDM wavelength demodulation module, an IoT wireless communication module, and a data processing and storage module. The solar self-powered module powers the on-site autonomous monitoring unit. The data processing and storage module provides data caching and control functions for the WDM wavelength demodulation module and the IoT wireless communication module, including: controlling the WDM wavelength demodulation module to receive and preliminarily process wavelength data collected by the FBG sensor in the new quasi-distributed WDM-FBG sensing optical cable and package it; and controlling the IoT wireless communication module to send the packaged data to a remote server.

5. The automated monitoring and early warning system for OPGW sag status of overhead transmission lines based on distributed sensing optical cables as described in claim 4, characterized in that, The solar self-powered module includes a solar panel, a power management unit, and an energy storage battery. The solar panel collects solar energy and converts it into electrical energy. The energy storage battery stores electrical energy and powers the on-site autonomous monitoring unit. The power management unit integrates an MPPT controller to maximize the solar energy collection efficiency of the solar panel and manage the charging and discharging process of the energy storage battery to maintain the long-term operation of the system.

6. The automated monitoring and early warning system for OPGW sag status of overhead transmission lines based on distributed sensing optical cables as described in claim 4, characterized in that, The data processing and storage module includes a memory and a controller. The controller is selected from low-power microcontrollers or embedded processors to control the operation of the on-site autonomous monitoring unit. The operation includes: The WDM demodulation module is controlled to periodically acquire wavelength data and perform preliminary processing on the wavelength data; The preliminary processing results of the wavelength data are packaged, and the memory is controlled to provide data caching function; The control IoT wireless communication module sends packaged data to a remote server.

7. The automated monitoring and early warning system for OPGW sag status of overhead transmission lines based on distributed sensing optical cables as described in claim 1, characterized in that, The remote server is a server cluster, including: The algorithm engine runs algorithms based on the preliminary processing results of wavelength data, including: temperature compensation algorithm and sag reconstruction algorithm based on multi-point FBG strain and temperature data; The user interface / visualization platform displays the real-time sag profile and early warning information of the line to maintenance personnel.

8. An automated monitoring and early warning method for the sag status of overhead power transmission lines (OPGW) based on distributed sensing optical cables, characterized in that, include: The on-site autonomous monitoring unit emits broadband light to the new quasi-distributed WDM-FBG sensing optical cable according to the preset sampling frequency, and receives the raw wavelength data reflected back from all FBG sensors. The on-site autonomous monitoring unit performs preliminary processing on the collected raw wavelength data and packages the preliminary processing results to send to the remote server; The remote server fits the sag state of the overhead transmission line based on the received preliminary processing results and generates an alarm signal.

9. The automated monitoring and early warning method for OPGW sag status of overhead transmission lines based on distributed sensing optical cables as described in claim 8, characterized in that, The on-site autonomous monitoring unit includes a solar self-powered module, a WDM wavelength demodulation module, an IoT wireless communication module, and a data processing and storage module. Its specific operating process is as follows: The data processing and storage module controls the WDM wavelength demodulation module to emit broadband light to the sensing optical cable according to the preset sampling frequency, and receives and demodulates the center wavelength reflected back by all FBG sensors. Then, the processed data is packaged, stored, and transmitted to a remote server through the Internet of Things wireless communication module. The power for the entire process is provided by the solar self-powered module.

10. The automated monitoring and early warning method for OPGW sag status of overhead transmission lines based on distributed sensing optical cables as described in claim 9, characterized in that, The remote server is equipped with an algorithm engine. After receiving the data, it first performs accurate temperature compensation through a temperature compensation algorithm, and then constructs a sag reconstruction model based on a sag reconstruction algorithm based on multi-point FBG strain and temperature data. The sag equation of the overhead transmission line within the span is obtained through numerical solution, which is used to fit the sag state of the overhead transmission line. Then, the real-time sag value of the lowest point or the real-time sag value of any point is obtained. A sag safety threshold is preset. When the real-time sag value exceeds the sag safety threshold,

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