A multi-parameter distributed optical fiber sensing method and system

Abstract

The application discloses a kind of multi-parameter distributed optical fiber sensing method and system, it is related to light sensing field, solve the problem that it is difficult to effectively utilize distributed optical fiber sensing technology to monitor the state of transmission line, method includes: the strain measured under different temperatures by intelligent sensing element is calibrated;The strain and amplitude at different positions on the surface of transmission line are processed, the strain deviation and real-time amplitude difference at different positions on the surface of transmission line at current time node are obtained;The strain factor and amplitude factor at different positions at current time node are analyzed;According to strain factor and amplitude factor, the different positions on the surface of transmission line are analyzed, and the position to be inspected or the correction strain interval is obtained;According to the correction strain interval, the strain of different positions on the surface of transmission line is analyzed, and the position to be inspected in transmission line is obtained, the application realizes the effective monitoring of transmission line state using distributed optical fiber sensing technology.

Description

Technical Field

[0001] This invention belongs to the field of distributed optical fiber sensing technology, specifically a multi-parameter distributed optical fiber sensing method and system. Background Technology

[0002] Distributed fiber optic sensors are sensors that use distributed fiber optic detection technology to measure or monitor the spatial distribution and time-varying information along the fiber optic transmission path. Distributed fiber optic sensors can be applied to many fields such as stress, strain and temperature monitoring of large structures, power transmission line monitoring, and transportation monitoring and safety systems. Currently, when monitoring power transmission lines, drone inspections are commonly used to determine whether the lines are in good condition. While drone inspections can effectively monitor surface damage, they are susceptible to weather and light intensity, and it is difficult to effectively monitor the internal condition of the lines. Meanwhile, distributed fiber optic sensing has multiple monitoring functions, including strain monitoring, temperature monitoring, and vibration amplitude monitoring, and is less affected by the environment. However, at present, it is difficult to effectively utilize distributed fiber optic sensing technology to monitor the condition of power transmission lines. Therefore, this invention proposes a multi-parameter distributed optical fiber sensing method and system. Summary of the Invention

[0003] The purpose of this invention is to propose a multi-parameter distributed optical fiber sensing method and system to solve the problem mentioned in the background art of difficulty in effectively using distributed optical fiber sensing technology to monitor the status of transmission lines.

[0004] To achieve the above objectives, the present invention adopts the following technical solution: Firstly, a multi-parameter distributed optical fiber sensing method, the method comprising: Step S1: Calibrate the strain measured by the smart sensing element at different temperatures, and obtain the temperature strain difference mapping package of the smart sensing element. Step S2: Process the strain and amplitude at different locations on the surface of the transmission line to obtain the strain deviation and real-time amplitude difference at different locations on the surface of the transmission line at the current time node. Step S3: Analyze the strain factor at different locations at the current time node based on the strain deviation, and analyze the amplitude factor at different locations at the current time node based on the real-time amplitude difference. Step S4: Analyze different locations on the transmission line surface based on strain factor and amplitude factor to obtain the location to be inspected or the corrected strain range. Step S5: Analyze the strain at different locations on the surface of the transmission line according to the corrected strain range, and obtain the locations to be inspected in the transmission line.

[0005] Furthermore, the calibration process in step S1 includes the following sub-steps: Step S101: Obtain the historical operating temperature of the transmission line, and compare the historical operating temperatures to obtain the maximum and minimum historical operating temperatures. Step S102: Using the minimum historical operating temperature as the left endpoint and the maximum historical operating temperature as the right endpoint, the operating temperature range of the transmission line is constructed. Step S103: Place the distributed optical fiber in a constant temperature test chamber and a variable temperature test chamber respectively. Set the temperature in the constant temperature test chamber to a fixed temperature and set the temperature in the variable temperature test chamber to any value within the working temperature range. Record the corresponding value as the calibration temperature.

[0006] Furthermore, the calibration process in step S1 also includes the following sub-steps: Step S104: Apply the same tension to the distributed optical fiber in the constant temperature test chamber and the variable temperature test chamber, measure the strain at different positions on the surface of the distributed optical fiber in the constant temperature test chamber and record it as constant temperature strain, and at the same time measure the strain at different positions on the surface of the distributed optical fiber in the variable temperature test chamber and record it as variable temperature strain. Step S105: Subtract the constant temperature strain from the variable temperature strain at the same location on the surface of the distributed optical fiber to obtain the strain difference at the corresponding location. Similarly, the strain difference at different locations on the surface of the distributed optical fiber is calculated. Step S106: Sum the strain difference values ​​at different locations, take the average value, and record the corresponding average value as the calibration strain difference value of the distributed optical fiber surface at the calibration temperature. Similarly, the temperature inside the variable temperature test chamber was set to different values ​​within the working temperature range, and the calibration strain difference values ​​of the distributed optical fiber surface at different calibration temperatures were analyzed. Step S107: Associate the calibration temperature with the corresponding calibration strain difference value to obtain the temperature strain difference mapping package of the intelligent sensing element.

[0007] Furthermore, the processing in step S2 includes the following sub-steps: Step S201: Obtain the real-time temperature and real-time strain at different locations on the surface of the transmission line at the current time node; Step S202: Select any position on the surface of the transmission line as the analysis object, query the corresponding calibration strain difference value in the temperature strain difference mapping package based on the real-time temperature at the corresponding position, and sum the real-time strain at the corresponding position with the calibration strain difference value to obtain the corrected strain at the corresponding position on the surface of the transmission line at the current time node. Similarly, different locations on the surface of the transmission line are selected as the analysis objects to analyze and obtain the corrected strain at different locations on the surface of the transmission line at the current time node. Step S203: Obtain the real-time temperature and real-time strain at different locations on the surface of the transmission line at any given time point, and repeat step S202 to analyze and obtain the corrected strain at different locations on the surface of the transmission line at any given time point.

[0008] Furthermore, the processing in step S2 also includes the following sub-steps: Step S204: Subtract the corrected strain at the corresponding position at the previous time node from the corrected strain at any position at the current time node to obtain the strain deviation at different positions on the transmission line surface at the current time node. Step S205: Obtain the real-time amplitude at any location on the surface of the transmission line at different time nodes, select any location as the analysis object, and subtract the real-time amplitude at the corresponding location at the previous time node from the real-time amplitude at the corresponding location at the current time node, thereby calculating the real-time amplitude difference at different locations on the surface of the transmission line at the current time node.

[0009] Furthermore, the analysis process in step S3 includes the following sub-steps: Step S301: If the strain deviation at the corresponding position on the transmission line surface at the current time node is greater than zero, then the strain factor at the corresponding position at the current time node is set to the first value. If the strain deviation at the corresponding location on the transmission line surface at the current time node is equal to zero, then the strain factor at the corresponding location at the current time node is set to the second value. If the strain deviation at the corresponding location on the transmission line surface at the current time node is less than zero, then the strain factor at the corresponding location at the current time node is set to the third value. Similarly, the strain deviation at any location on the surface of the transmission line at different time points is analyzed in the same way to obtain the strain factor at any location on the surface of the transmission line at different time points. Step S302: If the real-time amplitude difference at the corresponding position on the transmission line surface at the current time node is greater than zero, then set the amplitude factor at the corresponding position at the current time node to the first value. If the real-time amplitude difference at the corresponding location on the transmission line surface at the current time node is equal to zero, then the amplitude factor at the corresponding location at the current time node is set to the second value. If the real-time amplitude difference at the corresponding location on the transmission line surface at the current time node is less than zero, then the amplitude factor at the corresponding location at the current time node is set to the third value.

[0010] Furthermore, the analysis process in step S4 includes the following sub-steps: Step S401: Compare the strain factor and amplitude factor at any location on the surface of the transmission line at the current time node; If the strain factor and amplitude factor are the same at all locations on the surface of the transmission line at the current time point, then proceed to step S402. If the strain factor and amplitude factor are different at any location on the surface of the transmission line at the current time node, the corresponding location is recorded as the location to be analyzed, and the strain factor and amplitude factor at the location to be analyzed at different time nodes are analyzed to obtain the location to be inspected. Step S402: Sum the different corrected strains and take the average value to calculate the average corrected strain at all locations on the transmission line surface at the current time node. Calculate the standard deviation of the corrected strain at all locations on the transmission line surface at the current time node using the standard deviation formula. Step S403: Subtract the standard deviation of the corrected strain from the average corrected strain to obtain the lower limit value, add the average corrected strain and the standard deviation of the corrected strain to obtain the upper limit value, and construct the corrected strain range at all locations on the surface of the transmission line at the current time node with the lower limit value as the left endpoint and the upper limit value as the right endpoint. By analogy, the corrected strain range at all locations on the surface of the transmission line at different time points can be calculated.

[0011] Furthermore, the analysis process in step S401 includes the following steps: Step S4011: Obtain the strain factor and amplitude factor at the location to be analyzed at different time points; Step S4012: Compare the strain factor and amplitude factor at the location to be analyzed at different time points; If the strain factor and amplitude factor at the location to be analyzed are different at multiple time points, then the corresponding location is recorded as the location to be inspected. If the strain factor and amplitude factor at the location to be analyzed are different at one and only one time point, monitoring will continue.

[0012] Furthermore, the analysis process in step S5 includes the following sub-steps: Step S501: Compare the corrected strain at all locations on the surface of the transmission line with the corrected strain range at any given time point; If the corrected strain at all locations on the transmission line surface is within the corrected strain range at the corresponding time point, no operation will be performed. If, at any point on the surface of the transmission line at the corresponding time node, the corrected strain is not within the corrected strain range, then the corresponding location is recorded as the strain concentration location. Similarly, the corrected strain at all locations on the transmission line surface at different time points is compared with the corrected strain range to obtain the strain concentration locations on the transmission line surface at different time points. Step S502: If there is one and only one time node and the corresponding position is the strain concentration position, then no operation is performed. If multiple time points correspond to strain concentration locations, then the corresponding strain concentration location is recorded as the location to be inspected and an early warning is issued immediately.

[0013] Secondly, a multi-parameter distributed optical fiber sensing system includes a data acquisition module, a strain calibration module, a data processing module, a data analysis module, and a position analysis module. The data acquisition module is used to collect real-time temperature, real-time strain and real-time amplitude at any location on the surface of the transmission line at different time points and send them to the data processing module; the strain calibration module is used to calibrate the strain measured by the intelligent sensing element at different temperatures, obtain the temperature strain difference mapping package of the intelligent sensing element and send it to the data processing module. The data processing module is used to process the strain at different locations on the surface of the transmission line according to the temperature strain difference mapping package, and at the same time, it processes the amplitude at different locations on the surface of the transmission line at the current time node according to the real-time amplitude. The processing module obtains the strain deviation and the real-time amplitude difference at different locations on the surface of the transmission line at the current time node and sends them to the data analysis module. The processing module also obtains the corrected strain at different locations on the surface of the transmission line at the previous time node and sends it to the strain analysis module. The data analysis module is used to analyze the strain factor and amplitude factor at different locations at the current time point, and send the strain factor and amplitude factor to the location analysis module; The strain analysis module is used to analyze the corrected strain at different locations on the surface of the transmission line, obtain the corrected strain range, and send it to the location analysis module; the location analysis module is used to analyze the strain at different locations on the surface of the transmission line based on the strain factor, amplitude factor, and corrected strain range, thereby analyzing the locations to be inspected in the transmission line.

[0014] In summary, due to the adoption of the above technical solution, the beneficial effects of the present invention are: 1. This invention first calibrates the strain measured by the intelligent sensing element at different temperatures to obtain the temperature strain difference mapping package of the intelligent sensing element. Then, it processes the strain and amplitude at different locations on the transmission line surface to obtain the corrected strain, strain deviation and real-time amplitude difference at different locations on the transmission line surface at the current time node. This invention achieves effective correction of real-time strain. 2. This invention also analyzes the strain factor and amplitude factor at different locations at the current time node, and analyzes different locations on the transmission line surface based on the strain factor and amplitude factor to obtain the inspection location or the corrected strain range. Finally, it analyzes the strain at different locations on the transmission line surface based on the corrected strain range to obtain the inspection location in the transmission line. This invention realizes the effective monitoring of the transmission line status using distributed optical fiber sensing technology. Attached Figure Description

[0015] To facilitate understanding by those skilled in the art, the present invention will be further described below with reference to the accompanying drawings.

[0016] Figure 1 This is a flowchart of the method of the present invention; Figure 2 This is a flowchart of the present invention; Figure 3 This is a flowchart of step S4 in the present invention; Figure 4 This is an overall system block diagram of the present invention. Detailed Implementation

[0017] The technical solution of the present invention will be clearly and completely described below with reference to the embodiments. Obviously, the described embodiments are only some embodiments of the present invention, and 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.

[0018] Example 1, please refer to Figures 1-3 As shown, the technical solution provided by this invention is: a multi-parameter distributed optical fiber sensing method. This method uses distributed optical fibers to monitor the real-time status of different locations on the surface of a transmission line. First, distributed optical fibers are laid on the surface of the transmission line, and multiple intelligent sensing elements are installed inside the distributed optical fibers. The real-time temperature, real-time strain, and real-time amplitude monitored by the intelligent sensing elements are analyzed to obtain the locations to be inspected in the transmission line. The method includes the following steps: In this embodiment, the transmission line is divided into multiple segments by the transmission tower. Any segment of the transmission line is selected as the analysis object. The analysis process of the remaining transmission lines is the same as the analysis process of the analysis object in this embodiment. The intelligent sensing element is an intelligent sensor that integrates temperature detection, strain monitoring and vibration detection functions. Step S1: Calibrate the strain measured by the smart sensing element at different temperatures, and obtain the temperature strain difference mapping package of the smart sensing element. In this embodiment, the calibration process in step S1 includes the following sub-steps: Step S101: Obtain the historical operating temperature of the transmission line, and compare the historical operating temperatures to obtain the maximum and minimum historical operating temperatures. Step S102: Using the minimum historical operating temperature as the left endpoint and the maximum historical operating temperature as the right endpoint, the operating temperature range of the transmission line is constructed. Step S103: Place the distributed optical fiber in a constant temperature test chamber and a variable temperature test chamber respectively. Set the temperature in the constant temperature test chamber to a fixed temperature and set the temperature in the variable temperature test chamber to any value within the working temperature range. Record the corresponding value as the calibration temperature. Step S104: Apply the same tension to the distributed optical fiber in the constant temperature test chamber and the variable temperature test chamber, measure the strain at different positions on the surface of the distributed optical fiber in the constant temperature test chamber and record it as constant temperature strain, and at the same time measure the strain at different positions on the surface of the distributed optical fiber in the variable temperature test chamber and record it as variable temperature strain. Step S105: Subtract the constant temperature strain from the variable temperature strain at the same location on the surface of the distributed optical fiber to obtain the strain difference at the corresponding location. Similarly, the strain difference at different locations on the surface of the distributed optical fiber is calculated. Step S106: Sum the strain difference values ​​at different locations, take the average value, and record the corresponding average value as the calibration strain difference value of the distributed optical fiber surface at the calibration temperature. Similarly, the temperature inside the variable temperature test chamber was set to different values ​​within the working temperature range, and the calibration strain difference values ​​of the distributed optical fiber surface at different calibration temperatures were analyzed. Step S107: Associate the calibration temperature with the corresponding calibration strain difference value to obtain the temperature strain difference value mapping package of the intelligent sensing element. It should be noted that the monitoring data of the intelligent sensing element in the distributed optical fiber is easily affected by temperature during the strain monitoring process. Therefore, it is necessary to calibrate the strain difference value of the distributed optical fiber surface at different temperatures.

[0019] Step S2: Process the strain and amplitude at different locations on the surface of the transmission line to obtain the strain deviation and real-time amplitude difference at different locations on the surface of the transmission line at the current time node. In this embodiment, the processing in step S2 includes the following sub-steps: Step S201: Obtain the real-time temperature and real-time strain at different locations on the surface of the transmission line at the current time node; Specifically, real-time temperature and real-time strain can be obtained through intelligent sensing elements inside the distributed optical fiber; Step S202: Select any position on the surface of the transmission line as the analysis object, query the corresponding calibration strain difference value in the temperature strain difference mapping package based on the real-time temperature at the corresponding position, and sum the real-time strain at the corresponding position with the calibration strain difference value to obtain the corrected strain at the corresponding position on the surface of the transmission line at the current time node. Similarly, different locations on the surface of the transmission line are selected as the analysis objects to analyze and obtain the corrected strain at different locations on the surface of the transmission line at the current time node. In the specific implementation process, the real-time strain measured by the intelligent sensing element is the value of the superposition of the real mechanical strain and the pseudo strain caused by temperature on the transmission line, while the corrected strain is the real mechanical strain after removing the pseudo strain caused by temperature. Step S203: Obtain the real-time temperature and real-time strain at different locations on the surface of the transmission line at any given time point, and repeat step S202 to analyze and obtain the corrected strain at different locations on the surface of the transmission line at any given time point. Step S204: Subtract the corrected strain at the corresponding position at the previous time node from the corrected strain at any position at the current time node to obtain the strain deviation at different positions on the transmission line surface at the current time node. Step S205: Obtain the real-time amplitude at any location on the surface of the transmission line at different time nodes, select any location as the analysis object, and subtract the real-time amplitude at the corresponding location at the previous time node from the real-time amplitude at the corresponding location at the current time node, thereby calculating the real-time amplitude difference at different locations on the surface of the transmission line at the current time node.

[0020] Step S3: Analyze the strain factor at different locations at the current time node based on the strain deviation, and analyze the amplitude factor at different locations at the current time node based on the real-time amplitude difference. In this embodiment, the analysis process in step S3 includes the following sub-steps: Step S301: If the strain deviation at the corresponding position on the transmission line surface at the current time node is greater than zero, then the strain factor at the corresponding position at the current time node is set to the first value. If the strain deviation at the corresponding location on the transmission line surface at the current time node is equal to zero, then the strain factor at the corresponding location at the current time node is set to the second value. If the strain deviation at the corresponding location on the transmission line surface at the current time node is less than zero, then the strain factor at the corresponding location at the current time node is set to the third value. Similarly, the strain deviation at any location on the surface of the transmission line at different time points is analyzed in the same way to obtain the strain factor at any location on the surface of the transmission line at different time points. In this embodiment, the first value, the second value, and the third value have no fixed relationship. The strain factor is only used to represent the relationship between the strain deviation and zero. For example, the first value is equal to one, the second value is equal to zero, and the third value is equal to negative one. Step S302: If the real-time amplitude difference at the corresponding position on the transmission line surface at the current time node is greater than zero, then set the amplitude factor at the corresponding position at the current time node to the first value. If the real-time amplitude difference at the corresponding location on the transmission line surface at the current time node is equal to zero, then the amplitude factor at the corresponding location at the current time node is set to the second value. If the real-time amplitude difference at the corresponding location on the transmission line surface at the current time node is less than zero, then the amplitude factor at the corresponding location at the current time node is set to the third value. In this embodiment, the amplitude factor is only used to represent the relationship between the real-time amplitude difference and zero. The first value here should be the same as the first value in step S301, the second value should be the same as the second value in step S301, and the third value should be the same as the third value in step S301.

[0021] Step S4: Analyze different locations on the transmission line surface based on strain factor and amplitude factor to obtain the location to be inspected or the corrected strain range. In this embodiment, the analysis process in step S4 includes the following sub-steps: Step S401: Compare the strain factor and amplitude factor at any location on the surface of the transmission line at the current time node; If the strain factor and amplitude factor are the same at all locations on the surface of the transmission line at the current time point, then proceed to step S402. If the strain factor and amplitude factor are different at any location on the surface of the transmission line at the current time node, the corresponding location is recorded as the location to be analyzed, and the strain factor and amplitude factor at the location to be analyzed at different time nodes are analyzed to obtain the location to be inspected. It should be explained that, under normal circumstances, amplitude and strain are directly proportional. The fact that the strain factor and amplitude factor are the same indicates that the strain and amplitude at the corresponding position on the transmission line surface show the same trend of change. When the strain and amplitude show different trends of change, the corresponding position needs to be analyzed. In this embodiment, the analysis process of the location to be analyzed in step S401 includes the following steps: Step S4011: Obtain the strain factor and amplitude factor at the location to be analyzed at different time points; Step S4012: Compare the strain factor and amplitude factor at the location to be analyzed at different time points; If the strain factor and amplitude factor at the location to be analyzed are different at multiple time points, then the corresponding location is recorded as the location to be inspected. If the strain factor and amplitude factor at the location to be analyzed are different at one and only one time point, then monitoring will continue. In this embodiment, when the location to be inspected is determined through analysis, relevant personnel need to check the location. Step S402: Sum the different corrected strains and take the average value to calculate the average corrected strain at all locations on the transmission line surface at the current time node. Calculate the standard deviation of the corrected strain at all locations on the transmission line surface at the current time node using the standard deviation formula. Step S403: Subtract the standard deviation of the corrected strain from the average corrected strain to obtain the lower limit value, add the average corrected strain and the standard deviation of the corrected strain to obtain the upper limit value, and construct the corrected strain range at all locations on the surface of the transmission line at the current time node with the lower limit value as the left endpoint and the upper limit value as the right endpoint. By analogy, the corrected strain range at all locations on the surface of the transmission line at different time points can be calculated.

[0022] Step S5: Analyze the strain at different locations on the surface of the transmission line according to the corrected strain range, and obtain the locations to be inspected in the transmission line. In this embodiment, the analysis process in step S5 includes the following sub-steps: Step S501: Compare the corrected strain at all locations on the surface of the transmission line with the corrected strain range at any given time point; If the corrected strain at all locations on the transmission line surface is within the corrected strain range at the corresponding time point, no operation will be performed. If, at any point on the surface of the transmission line at the corresponding time node, the corrected strain is not within the corrected strain range, then the corresponding location is recorded as the strain concentration location. Similarly, the corrected strain at all locations on the transmission line surface at different time points is compared with the corrected strain range to obtain the strain concentration locations on the transmission line surface at different time points. Step S502: If there is one and only one time node and the corresponding position is the strain concentration position, then no operation is performed. If multiple time points correspond to strain concentration locations, then the corresponding strain concentration location is recorded as the location to be inspected and an early warning is issued immediately. In the specific implementation process, after receiving an early warning, relevant personnel need to check the location to be inspected.

[0023] Example 2, please refer to Figure 4 As shown, based on another concept of the same invention, a multi-parameter distributed optical fiber sensing system is proposed, including a data acquisition module, a strain calibration module, a data processing module, a data analysis module and a position analysis module. The data acquisition module is used to collect real-time temperature, real-time strain and real-time amplitude at any location on the surface of the transmission line at different time points and send them to the data processing module; the strain calibration module is used to calibrate the strain measured by the intelligent sensing element at different temperatures, obtain the temperature strain difference mapping package of the intelligent sensing element and send it to the data processing module. The data processing module is used to process the strain at different locations on the surface of the transmission line according to the temperature strain difference mapping package, and at the same time, it processes the amplitude at different locations on the surface of the transmission line at the current time node according to the real-time amplitude. The processing module obtains the strain deviation and the real-time amplitude difference at different locations on the surface of the transmission line at the current time node and sends them to the data analysis module. The processing module also obtains the corrected strain at different locations on the surface of the transmission line at the previous time node and sends it to the strain analysis module. The data analysis module is used to analyze the strain factor and amplitude factor at different locations at the current time point, and send the strain factor and amplitude factor to the location analysis module; The strain analysis module is used to analyze the corrected strain at different locations on the surface of the transmission line, obtain the corrected strain range, and send it to the location analysis module; the location analysis module is used to analyze the strain at different locations on the surface of the transmission line based on the strain factor, amplitude factor, and corrected strain range, thereby analyzing the locations to be inspected in the transmission line.

[0024] The preferred embodiments of the present invention disclosed above are merely illustrative of the invention. These preferred embodiments do not exhaustively describe all details, nor do they limit the invention to any specific implementation. Clearly, many modifications and variations can be made based on the content of this specification. This specification selects and specifically describes these embodiments to better explain the principles and practical applications of the invention, thereby enabling those skilled in the art to better understand and utilize the invention. The invention is limited only by the claims and their full scope and equivalents.

Claims

1. A multi-parameter distributed optical fiber sensing method, characterized in that, The methods include: Step S1: Calibrate the strain measured by the smart sensing element at different temperatures, and obtain the temperature strain difference mapping package of the smart sensing element. Step S2: Process the strain and amplitude at different locations on the surface of the transmission line to obtain the strain deviation and real-time amplitude difference at different locations on the surface of the transmission line at the current time node. Step S3: Analyze the strain factor at different locations at the current time node based on the strain deviation, and analyze the amplitude factor at different locations at the current time node based on the real-time amplitude difference. Step S4: Analyze different locations on the transmission line surface based on strain factor and amplitude factor to obtain the location to be inspected or the corrected strain range. Step S5: Analyze the strain at different locations on the surface of the transmission line according to the corrected strain range, and obtain the locations to be inspected in the transmission line.

2. The multi-parameter distributed optical fiber sensing method according to claim 1, characterized in that, The calibration process in step S1 includes the following sub-steps: Step S101: Obtain the historical operating temperature of the transmission line, and compare the historical operating temperatures to obtain the maximum and minimum historical operating temperatures. Step S102: Using the minimum historical operating temperature as the left endpoint and the maximum historical operating temperature as the right endpoint, the operating temperature range of the transmission line is constructed. Step S103: Place the distributed optical fiber in a constant temperature test chamber and a variable temperature test chamber respectively. Set the temperature in the constant temperature test chamber to a fixed temperature and set the temperature in the variable temperature test chamber to any value within the working temperature range. Record the corresponding value as the calibration temperature.

3. The multi-parameter distributed optical fiber sensing method according to claim 2, characterized in that, The calibration process in step S1 further includes the following sub-steps: Step S104: Apply the same tension to the distributed optical fiber in the constant temperature test chamber and the variable temperature test chamber, measure the strain at different positions on the surface of the distributed optical fiber in the constant temperature test chamber and record it as constant temperature strain, and at the same time measure the strain at different positions on the surface of the distributed optical fiber in the variable temperature test chamber and record it as variable temperature strain. Step S105: Subtract the constant temperature strain from the variable temperature strain at the same location on the surface of the distributed optical fiber to obtain the strain difference at the corresponding location. Similarly, the strain difference at different locations on the surface of the distributed optical fiber is calculated. Step S106: Sum the strain difference values ​​at different locations, take the average value, and record the corresponding average value as the calibration strain difference value of the distributed optical fiber surface at the calibration temperature. Similarly, the temperature inside the variable temperature test chamber was set to different values ​​within the working temperature range, and the calibration strain difference values ​​of the distributed optical fiber surface at different calibration temperatures were analyzed. Step S107: Associate the calibration temperature with the corresponding calibration strain difference value to obtain the temperature strain difference mapping package of the intelligent sensing element.

4. The multi-parameter distributed optical fiber sensing method according to claim 1, characterized in that, The processing procedure in step S2 includes the following sub-steps: Step S201: Obtain the real-time temperature and real-time strain at different locations on the surface of the transmission line at the current time node; Step S202: Select any position on the surface of the transmission line as the analysis object, query the corresponding calibration strain difference value in the temperature strain difference mapping package based on the real-time temperature at the corresponding position, and sum the real-time strain at the corresponding position with the calibration strain difference value to obtain the corrected strain at the corresponding position on the surface of the transmission line at the current time node. Similarly, different locations on the surface of the transmission line are selected as the analysis objects to analyze and obtain the corrected strain at different locations on the surface of the transmission line at the current time node. Step S203: Obtain the real-time temperature and real-time strain at different locations on the surface of the transmission line at any given time point, and repeat step S202 to analyze and obtain the corrected strain at different locations on the surface of the transmission line at any given time point.

5. The multi-parameter distributed optical fiber sensing method according to claim 4, characterized in that, The processing in step S2 also includes the following sub-steps: Step S204: Subtract the corrected strain at the corresponding position at the previous time node from the corrected strain at any position at the current time node to obtain the strain deviation at different positions on the transmission line surface at the current time node. Step S205: Obtain the real-time amplitude at any location on the surface of the transmission line at different time nodes, select any location as the analysis object, and subtract the real-time amplitude at the corresponding location at the previous time node from the real-time amplitude at the corresponding location at the current time node, thereby calculating the real-time amplitude difference at different locations on the surface of the transmission line at the current time node.

6. The multi-parameter distributed optical fiber sensing method according to claim 1, characterized in that, The analysis process in step S3 includes the following sub-steps: Step S301: If the strain deviation at the corresponding position on the transmission line surface at the current time node is greater than zero, then the strain factor at the corresponding position at the current time node is set to the first value. If the strain deviation at the corresponding location on the transmission line surface at the current time node is equal to zero, then the strain factor at the corresponding location at the current time node is set to the second value. If the strain deviation at the corresponding location on the transmission line surface at the current time node is less than zero, then the strain factor at the corresponding location at the current time node is set to the third value. Similarly, the strain deviation at any location on the surface of the transmission line at different time points is analyzed in the same way to obtain the strain factor at any location on the surface of the transmission line at different time points. Step S302: If the real-time amplitude difference at the corresponding position on the transmission line surface at the current time node is greater than zero, then set the amplitude factor at the corresponding position at the current time node to the first value. If the real-time amplitude difference at the corresponding location on the transmission line surface at the current time node is equal to zero, then the amplitude factor at the corresponding location at the current time node is set to the second value. If the real-time amplitude difference at the corresponding location on the transmission line surface at the current time node is less than zero, then the amplitude factor at the corresponding location at the current time node is set to the third value.

7. The multi-parameter distributed optical fiber sensing method according to claim 1, characterized in that, The analysis process in step S4 includes the following sub-steps: Step S401: Compare the strain factor and amplitude factor at any location on the surface of the transmission line at the current time node; If the strain factor and amplitude factor are the same at all locations on the surface of the transmission line at the current time point, then proceed to step S402. If the strain factor and amplitude factor are different at any location on the surface of the transmission line at the current time node, the corresponding location is recorded as the location to be analyzed, and the strain factor and amplitude factor at the location to be analyzed at different time nodes are analyzed to obtain the location to be inspected. Step S402: Sum the different corrected strains and take the average value to calculate the average corrected strain at all locations on the transmission line surface at the current time node. Calculate the standard deviation of the corrected strain at all locations on the transmission line surface at the current time node using the standard deviation formula. Step S403: Subtract the standard deviation of the corrected strain from the average corrected strain to obtain the lower limit value, add the average corrected strain and the standard deviation of the corrected strain to obtain the upper limit value, and construct the corrected strain range at all locations on the surface of the transmission line at the current time node with the lower limit value as the left endpoint and the upper limit value as the right endpoint. By analogy, the corrected strain range at all locations on the surface of the transmission line at different time points can be calculated.

8. The multi-parameter distributed optical fiber sensing method according to claim 7, characterized in that, The analysis process in step S401 includes the following steps: Step S4011: Obtain the strain factor and amplitude factor at the location to be analyzed at different time points; Step S4012: Compare the strain factor and amplitude factor at the location to be analyzed at different time points; If the strain factor and amplitude factor at the location to be analyzed are different at multiple time points, then the corresponding location is recorded as the location to be inspected. If the strain factor and amplitude factor at the location to be analyzed are different at one and only one time point, monitoring will continue.

9. The multi-parameter distributed optical fiber sensing method according to claim 1, characterized in that, The analysis process in step S5 includes the following sub-steps: Step S501: Compare the corrected strain at all locations on the surface of the transmission line with the corrected strain range at any given time point; If the corrected strain at all locations on the transmission line surface is within the corrected strain range at the corresponding time point, no operation will be performed. If, at any point on the surface of the transmission line at the corresponding time node, the corrected strain is not within the corrected strain range, then the corresponding location is recorded as the strain concentration location. Similarly, the corrected strain at all locations on the transmission line surface at different time points is compared with the corrected strain range to obtain the strain concentration locations on the transmission line surface at different time points. Step S502: If there is one and only one time node and the corresponding position is the strain concentration position, then no operation is performed. If multiple time points correspond to strain concentration locations, then the corresponding strain concentration location is recorded as the location to be inspected and an early warning is issued immediately.

10. A multi-parameter distributed optical fiber sensing system, characterized in that, A multi-parameter distributed optical fiber sensing method according to any one of claims 1-9 includes a data acquisition module, a strain calibration module, a data processing module, a data analysis module, and a position analysis module; The data acquisition module is used to collect real-time temperature, real-time strain and real-time amplitude at any location on the surface of the transmission line at different time points and send them to the data processing module; the strain calibration module is used to calibrate the strain measured by the intelligent sensing element at different temperatures, obtain the temperature strain difference mapping package of the intelligent sensing element and send it to the data processing module. The data processing module is used to process the strain at different locations on the surface of the transmission line according to the temperature strain difference mapping package, and at the same time, it processes the amplitude at different locations on the surface of the transmission line at the current time node according to the real-time amplitude. The processing module obtains the strain deviation and the real-time amplitude difference at different locations on the surface of the transmission line at the current time node and sends them to the data analysis module. The processing module also obtains the corrected strain at different locations on the surface of the transmission line at the previous time node and sends it to the strain analysis module. The data analysis module is used to analyze the strain factor and amplitude factor at different locations at the current time point, and send the strain factor and amplitude factor to the location analysis module; The strain analysis module is used to analyze the corrected strain at different locations on the surface of the transmission line, obtain the corrected strain range, and send it to the location analysis module. The location analysis module is used to analyze the strain at different locations on the surface of the transmission line based on the strain factor, amplitude factor and corrected strain range, thereby analyzing and obtaining the locations to be inspected in the transmission line.

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