Special-shaped wire surface stress monitoring system and method
By using a flexible substrate 3D printed with Flexible50A resin and insulating straps to fix the FBG stress sensor on irregularly shaped conductors, and combining it with a moving average filtering algorithm, the problems of difficult fixation, large damage, and low monitoring accuracy of traditional sensors on irregularly shaped conductors are solved, and high-precision non-destructive strain monitoring is achieved.
Patent Information
- Application Number
- CN202510927975.7
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-07-07
- Publication Date
- 2025-11-21
AI Technical Summary
Traditional FBG stress sensors suffer from problems such as difficulty in fixing, significant damage, and low monitoring accuracy in monitoring the surface strain of irregularly shaped conductors, making it difficult to meet the requirements of high precision and high robustness.
A flexible substrate was 3D printed using Flexible50A resin. The inner surface of the substrate was matched with the geometric parameters of the conductor. An FBG stress sensor was embedded in the substrate and fixed with insulating tape. Combined with moving average filtering and steady-state data processing algorithms, strain monitoring was achieved.
It enables high-precision non-destructive monitoring of the surface strain of irregularly shaped conductors, reduces the degree of damage to the conductor surface, and improves the accuracy and reliability of monitoring.
Smart Images
Figure CN120992073A_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The present application relates to the technical field of optical fiber sensing, in particular to a special-shaped conductor surface stress monitoring system and method, which solves the problems of difficult sensor fixing, large surface damage and low monitoring precision under wind load. BACKGROUND
[0002] With the rapid development of power transmission, aerospace, rail transportation and other fields, special-shaped conductors (variable cross-section conductors, etc.) have excellent mechanical and electrical properties under complex working conditions due to their special structure, and are widely used in high-voltage transmission line scenes. However, special-shaped conductors are easily affected by wind vibration, icing, mechanical fatigue and temperature alternation during long-term service, which leads to abnormal surface strain distribution of the conductors, and further causes safety hazards such as conductor breakage and deformation failure. Therefore, real-time and accurate monitoring of the surface strain of special-shaped conductors has become an important requirement to ensure the safe operation of key infrastructure.
[0003] Traditional FBG stress sensors are fixed by adhesion, which does not affect the surface of the measured structure during stress monitoring. However, permanent bonding may be formed after adhesion, and if the sensor needs to be replaced or repaired, the peeling process may damage the conductor surface protection layer. The adhesive fixing method has low long-term reliability, high risk of signal distortion, poor process controllability and other defects in the surface strain monitoring of special-shaped conductors, and it is difficult to meet the high-precision and high-robustness monitoring requirements. SUMMARY
[0004] The technical problem solved by the present application is that the present application provides a special-shaped conductor surface stress monitoring system and method, which realizes high-precision and non-destructive monitoring of the surface strain of special-shaped conductors, and improves the interface adaptability and service life of FBG stress sensors and special-shaped conductors.
[0005] Technical solution: The special-shaped conductor surface stress monitoring system provided by the present application comprises: A strain sensing and collecting module, the strain sensing and collecting module comprises a semicircular flexible substrate, an FBG stress sensor embedded in the flexible substrate, and an insulating band for fixing the flexible substrate; A strain signal analysis module, the strain signal analysis module comprises a fiber grating demodulator and a computer; Wherein, the inner surface profile of the flexible substrate matches the geometric parameters of the outer surface of the special-shaped conductor, and three semicircular through holes are provided in the flexible substrate for embedding the FBG stress sensor, and square through holes are provided on both sides of the flexible substrate for the insulating band to pass through.
[0006] Preferably, the material of the flexible base is Flexible 50A resin, and the inner surface profile parameters thereof include: groove width a = 2.5 mm, groove depth b = 1.6 mm, round corner radius c = 0.5 mm, and transition round corner radius z = 1.5 mm. The flexible base has a thickness of 1.3-2.5 mm and a width d > FBG grating segment length + 2 times the width of the insulating band.
[0007] Preferably, the number of FBG stress sensors is 3, and the grating lengths thereof are 6 mm, and the center wavelengths thereof are 1535 nm, 1545 nm and 1555 nm, respectively. The three FBG stress sensors are symmetrically distributed along the conductor with an axial spacing of 7.5 meters, and the second FBG stress sensor is located at the midpoint of the conductor.
[0008] The application discloses a special-shaped conductor surface stress monitoring method, which comprises the following steps: Step 1: sensor selection and structure design; Step 2: 3D printing of a flexible base; Step 3: building of a stress monitoring system; Step 4: acquisition of center wavelength data; Step 5: data processing to obtain strain values.
[0009] Preferably, step 1 comprises: determining the positioning size of the semicircular through hole through fluid-structure coupling simulation, that is, 0.25 mm away from the inner surface of the flexible base and located on the center line of the split surface; and determining the positioning size of the square through hole through statics simulation, that is, 1 mm away from the bottom of the cross section and 2.1 mm away from the side, and the size width e = 5 mm and the height f = 1 mm.
[0010] Preferably, step 3 comprises: connecting the FBG stress sensors to the fiber grating demodulator through fiber jumpers; and providing fiber flanges at both ends of the fiber jumpers and cleaning the connection interfaces with anhydrous alcohol.
[0011] Preferably, in step 4, the center wavelength initial value matrixes X0, Y0 and Z0 of each monitoring point of the three FBG stress sensors are acquired and recorded; .
[0012] Preferably, the specific steps of step 5 are as follows: Step 51: acquiring the center wavelength original data matrixes X1, Y1 and Z1 with a frequency of 100 Hz within 30 seconds; ; Step 52: adopting sliding average filtering with a window size n = 5 to generate the filtering matrixes X2, Y2 and Z2; Step 53: take the last 10 seconds of steady-state data to calculate the wavelength mean matrix X3, Y3, Z3; Step 54: calculate the wavelength offset Δλ = steady-state matrix - initial value matrix, i.e. Δλ x , Δλ y , Δλ z , Δλ x = X3-X0; Δλy=Y3-Y0, Δλz=Z3-Z0; ; Step 55: use the strain sensitivity coefficient K e to convert Δλ into strain value: ε=Δλ / K e ; the K e value is determined through calibration test: install FBG stress sensor and resistance strain gauge on the surface of the profiled conductor test piece synchronously, grade the loading bending displacement to 500με, fit the strain-wavelength offset curve slope to obtain K e value.
[0013] The application further discloses a computer readable storage medium, which has a computer program stored thereon, and the program realizes the steps of the profiled conductor surface stress monitoring method when executed by a processor.
[0014] The application further discloses a computer device, which comprises a memory, a processor and a computer program stored in the memory, and the processor realizes the steps of the profiled conductor surface stress monitoring method when executing the program.
[0015] The application provides a profiled conductor surface stress monitoring system and method, and realizes the following technical effects: 1. The sensor of the application is made of a flexible matrix prepared by Flexible 50A resin 3D printing, the inner surface profile of which is accurately matched with the geometric parameters of the conductor; three semicircular through holes are arranged in the flexible matrix to embed FBG stress sensors, and the two side holes of the flexible matrix are penetrated into the insulating band of PA6 material for convenient fixation, so that the flexible matrix + insulating band fixation realizes zero surface damage of the profiled conductor; the three FBG stress sensors are symmetrically arranged along the axial distance of 7.5 meters of the conductor, and cover the local bending strain caused by the minimum bending radius of 12 meters; the moving average filtering (window n=5) and steady-state data processing algorithm are adopted, combined with the conversion strain Kε obtained through calibration, so that the filtering algorithm improves the signal-to-noise ratio, and the actual measurement strain error is less than 5%; 2、The application can solve the technical problems of difficulty in fixing the sensor and stress monitoring accuracy in the process of monitoring the surface strain of the special-shaped insulated conductor under wind load, and can significantly reduce the damage degree to the conductor surface while accurately obtaining the uniform strain change data on the conductor surface through the FBG stress sensor flexible matrix and sensor monitoring method, thereby providing a reliable and efficient solution for strain monitoring of the special-shaped insulated conductor under wind load. BRIEF DESCRIPTION OF DRAWINGS
[0016] Figure 1 The monitoring system architecture diagram of the special-shaped conductor of the application; Figure 2 The assembly structure schematic diagram of the monitoring system of the special-shaped conductor of the application; Figure 3 The sensor flexible matrix structure schematic diagram of the application; Figure 4 The end view of the sensor flexible matrix structure of the application; Figure 5 The special-shaped conductor surface stress monitoring flowchart of the application.
[0017] Reference signs: 1, strain sensing and collecting module; 2, strain signal analysis module; 3, FBG stress sensor; 4, flexible matrix; 41, inner surface profile; 42, semicircular through hole; 43, square through hole; 5, insulated bandage; 6, optical fiber jumper; 7, optical fiber grating demodulator; 8, computer; 9, computer program; 10, special-shaped conductor. DETAILED DESCRIPTION
[0018] In order to make the purpose, technical scheme and advantages of the embodiments of the application more clear, the following will combine the attached drawings to make a clear and complete description of the technical scheme of the embodiments of the application. Figures 1-5 The technical scheme of the embodiments of the application is described clearly and completely. Obviously, the described embodiments are part of the embodiments of the application, not all the embodiments. Based on the described embodiments of the application, all other embodiments obtained by those skilled in the art belong to the scope of protection of the application.
[0019] Embodiment 1: as Figures 1-3As shown, the profiled conductor surface stress monitoring system of the present application comprises a strain sensing acquisition module 1 and a strain signal analysis module 2. The strain sensing acquisition module 1 comprises a semicircular arc-shaped flexible substrate 4, an FBG stress sensor 3 embedded in the flexible substrate 4, and an insulating band 5 for fixing the flexible substrate 4. The inner surface profile 41 of the flexible substrate 4 matches the outer surface geometric parameters of the profiled conductor 10. Three semicircular through holes 42 are provided in the flexible substrate 4 for embedding the FBG stress sensor 3. Square through holes 43 are provided on both sides of the flexible substrate 4 for the insulating band 5 to pass through. The strain signal analysis module 2 comprises a fiber grating demodulator 7 and a computer 8. The FBG stress sensor 3 is connected to the fiber grating demodulator 7 through a fiber jumper 6. The fiber jumper 6 is provided with fiber flanges at both ends, and the connection interfaces are cleaned with anhydrous alcohol.
[0020] In a preferred embodiment, as shown in Figure 4 The material of the flexible substrate 4 is Flexible 50A resin. The inner surface profile 41 parameters include: groove width a = 2.5 mm, groove depth b = 1.6 mm, round corner radius c = 0.5 mm, and transition round corner radius z = 1.5 mm. The thickness of the flexible substrate 4 is 1.3-2.5 mm, and the width d is greater than the FBG grating length plus twice the insulating band width.
[0021] In a preferred embodiment, as shown in Figure 2 The number of FBG stress sensors 3 is 3, the grating length is 6 mm, and the center wavelengths are 1535 nm, 1545 nm, and 1555 nm, respectively. The three FBG stress sensors 3 are symmetrically distributed along the conductor axial distance of 7.5 meters, and the second FBG stress sensor 3 is located at the midpoint of the conductor.
[0022] Embodiment 2: As shown in Figure 5 The present application discloses a monitoring method of an FBG strain sensor, comprising the following steps: (1) Sensor selection and structure design, the specific steps are: 1. Establish the inner surface shape of the flexible substrate 4 of the sensor according to the structure of the profiled conductor 10. The groove width is 2.5 mm, the groove depth is 1.6 mm, the round corner radius at the bottom of the groove is 0.5 mm, and the transition round corner radius at both ends of the groove is 1.5 mm. Design the inner contact surface profile size of the sensing substrate as groove width a = 2.5 mm, groove depth b = 1.6 mm, round corner radius c = 0.5 mm, and transition round corner radius z = 1.5 mm.
[0023] 2. Determine the thickness and width of the flexible substrate 4. According to the outer shape size of the outer envelope layer of the profiled conductor 10, the thickness of the flexible substrate 4 is not too large, which is 1.3-2.5 mm. The width d is greater than the FBG grating length plus twice the insulating band width.
[0024] 3. According to the size of the FBG stress sensor 3 after encapsulation, three semicircular through holes are opened on the contact surface of the profile 41 of the flexible substrate 4 and the profiled wire 10, and the radius of the semicircular through hole is set as r; wherein the position and size of the semicircular through hole are determined according to the fluid-structure coupling simulation: (1) According to the material properties of the flexible substrate 4 and the fluid properties, set the simulation parameters; (2) Grid division is performed on the outer flow field; (3) Select the corresponding turbulence model, set the boundary conditions of the fluid domain of the outer flow field, and perform fluid outer flow field simulation; (4) Set the fixed constraint in the static structure module and perform grid division, import the pressure load of the flexible substrate 4, and solve the stress of the inner surface; (5) Through the analysis of the internal stress distribution, the positioning size and the shaping size of the embedded semicircular through hole are completed; (6) Compare the center strain effect when embedded at different depths, and select the one with the maximum stress distribution and relatively uniform change as the best embedding depth.
[0025] Through analysis, it is found that the semicircular through hole bus is 0.25mm away from the inner surface of the FBG stress sensor 3, and the effect is best at the three split inner surface midlines of the inner surface profile 41.
[0026] 4. According to the cross-sectional size of the semicircular flexible substrate 4, two square through holes are opened along the inner arc surface to install the insulating bandage, and the width e and the height f of the square through hole ensure that e<0.5d and f<1.3mm; wherein the positioning size and the shape size of the square through hole are determined according to the statics simulation: (1) According to the flexible material of the flexible substrate 4, set the material parameters of the simulation; (2) Divide the grid, set the boundary conditions, add the normal force along the bottom surface of the square through hole, and set the fixed support on the two sides of the flexible substrate 4; (3) Perform simulation on the deformation amount of the bottom of the square through hole, and determine the positioning size of the bottom of the square through hole; the shaping size of the square through hole is the width e and the height f, which ensures that e<0.5d and f<1.3, and the values of e and f are changed multiple times, the deformation amount of the flexible substrate 4 is compared, and the one with larger deformation and uniform change in the grid area is selected as the optimal shaping size.
[0027] According to the simulation results, the positioning size of the square through hole is 1mm away from the bottom of the cross section and 2.1mm away from the side of the cross section, the shaping size is width e=5mm and height f=1mm, and the two sides of the cross section are symmetrically distributed along the center line of the flexible substrate 4.
[0028] The strain sensing acquisition module 1 of the FBG stress sensor 3 for monitoring stress, in order to achieve the maximum strain effect and ensure the stability of the structure, the structural size parameters of the elastomer matrix are determined as follows: width d = 20 mm, outer diameter R = 13.25 mm, maximum thickness m = 2.5 mm, and minimum thickness n = 1.3 mm. The size of the inner surface profile 41 of the flexible matrix 4 is as follows: groove width a = 2.5 mm, groove depth b = 1.6 mm, round corner radius c = 0.5 mm, transition round corner radius z = 1.5 mm, and opening angle k = 30°. The positioning size of the square through hole is as follows: distance from the section bottom 1 mm, distance from the section side 2.1 mm, shaped size width e = 5 mm, and height f = 1 mm.
[0029] 5. The number and length of the FBG stress sensor 3 grid area of the profiled wire 10 are determined, and the specific implementation steps are as follows: (1) Refer to the technical specifications of the optical fiber demodulator to obtain the maximum wavelength measurement range λ max = 10 nm of a single channel.
[0030] (2) The working wavelength buffer zone λ n of a single grating point (for example, λ n = 0.5 nm); the maximum strain range ε (for example, ε = 1000 με) that needs to be measured for each grating point in the profiled wire 10; the strain sensitivity coefficient K e , which is determined by the sensor model, K e = 1.2 pm / με. The FBG strain sensor grading loading sensitivity calibration test is performed, and the determination steps of the strain sensitivity coefficient K e are as follows: ① Prepare a material specimen of the profiled wire 10, and embed the FBG stress sensor 3 and the resistance strain gauge in the surface groove of the specimen respectively, and the groove shape is consistent with the surface groove shape of the profiled wire 10; ② Install the specimen on a three-point bending clamp; ③ Connect the optical fiber demodulator with the strain sensing acquisition module 1, and set the sampling frequency to 100 Hz; ④ Set the temperature of the thermostat to 25℃, and stabilize for 30 min; when the temperature is stable, record the center wavelength λ0 of the FBG strain sensor and the reading ε0 of the strain gauge; ⑤ Use a universal material testing machine to apply a bending displacement to the specimen at a rate of 0.1 mm / min, and the load range is 0-500 με. Load five times, and each load level is 100 με. After each load level is stable, record the center wavelength λ i of the FBG strain sensor and the reading ε i of the resistance strain gauge. ⑥ Calculate the wavelength offset Δλ i = λ i- λ0, plot ε i - Δλ i Strain wavelength fitting straight line graph, slope is strain sensitivity coefficient K ε .
[0031] (3) Substitute the formula to calculate the theoretical maximum allowed grating number: ; Bring the strain sensitivity coefficient Kε into the formula: ; It is calculated that the theoretical maximum allowed grating number is 5.
[0032] (4) In order to reserve the wavelength buffer margin, combined with the length of a special-shaped wire 10, selecting n=3 can reduce the aliasing risk, and reduce the cost and improve the installation efficiency of the FBG stress sensor 3.
[0033] (5) According to the monitoring of local strain of the special-shaped wire 10, the spatial distribution rate is required to be ≤5mm, according to the empirical formula: ; Selecting a grating length of 6mm is more appropriate to balance the local strain capture ability and system stability.
[0034] As can be seen from the above, the grating number of the FBG stress sensor 3 for monitoring the surface stress of a special-shaped wire 10 is 3, the grating length is 6mm, and the center wavelengths are 1535mm, 1545mm and 1555mm respectively.
[0035] (II) 3D printing flexible matrix 4, the specific steps are: 1. According to the parameters of the FBG stress sensor 3, a model of the sensor is established, and then converted into stl format and imported into the slicing software Halotbox of 3D printing.
[0036] 2. Set the 3D printing parameters: the model distance from the platform height is 5.0mm, the support density is 50%, the support tip diameter is 0.3mm, the support diameter is 1mm, the initial exposure is 30s, the printing exposure is 8s, the printing rising height is 8mm, the motor speed is 3mm / s, the light-off delay is 4s, the bottom layer exposure layer number is 5, after setting, slicing, the slicing layer thickness is 0.05mm, after slicing, the file is converted into CXDLP format.
[0037] 3. Calibrate the 3D printer and perform leveling operation; import the file with sensor model into the 3D printer; use clean test alcohol wet paper to wipe the light curing forming disc and resin tank, pour flexible 50A material into the resin tank, use file parameters to print the sensor, clean and place the sensor in the curing device for curing, and take out the sensor.
[0038] (Three) to build a stress monitoring system, the specific steps are: 1, using the arrangement along the three split zone of the inner surface of the special-shaped conductor 10 line, FBG stress sensor 3 buried in the flexible matrix 4 semicircular hole; in the square hole inside the binding tape, and cut off the excess part of the insulating tape.
[0039] 2, prepare the optical fiber jumper and install the optical fiber flange, the length of the optical fiber jumper is determined according to the distance from the conductor to the optical fiber demodulator, and there is a 1-2 meter margin to adjust the position of each device to avoid the situation that the optical fiber jumper cannot be connected to the device.
[0040] 3, FBG strain sensor is connected with one end of the optical fiber flange and the optical fiber jumper, and the other end of the optical fiber jumper is connected with the optical fiber demodulator through the optical fiber flange, and the connection interface is cleaned with anhydrous alcohol; then the optical fiber demodulator is connected with the computer through the data interface, and the data collection is prepared.
[0041] 4, use Launch FbgCollect software to monitor the center wavelength of 3 channels, and store the data on the computer hard disk.
[0042] (Four) collect center wavelength data, the specific steps are: 1, fix the special-shaped conductor 10 arranged with FBG strain sensor firmly to avoid shaking; connect the 3 FBG stress sensors 3 through the 3 channels of the optical fiber flange and the optical fiber demodulator, clean the channel connection of the flange and the optical fiber demodulator with anhydrous alcohol and optical fiber cleaning pen to avoid dust increasing loss. Open Launch FbgCollect software to determine that the signal connection is normal.
[0043] 2, install 3 flexible matrices 4 and corresponding FBG stress sensors 3 on the special-shaped conductor 10 through the insulating tape, and record the initial values of the center wavelength of the three FBG strain sensors at each monitoring point λ x,1 , λ x,2 , λ x,3 ; λ y,1 , λ y,2 , λ y,3 ; λ z,1 , λ z,2 , λ z,3 , get the initial value matrix X0, Y0, Z0: ; Wherein, the specific collection steps are: (1) preheat the demodulator, check the channel status indicator light, and ensure that the light source is stable; (2) Set the sampling frequency to 100 Hz to adapt to the fluctuation frequency of wind speed under different customs; (3) Click "Start Collection" on the software interface to start the 30s countdown timer and the anemometer simultaneously; the collection time is set to 30s, and 3000 groups of data can be collected in 30s for a single grid area, 3x3000 groups of data can be collected for each FBG stress sensor 3, and the file is saved in the setting page and the central wavelength data is stored.
[0044] 3. When the external wind load changes, the computer collects the central wavelength data generated by the 3 windward surfaces of the special-shaped conductor 10 through the fiber demodulator, and the collection time is set to 30s.
[0045] (Five) Data processing to obtain strain value, the specific steps are: 1. Process the collected central wavelength data, 100Hz is the collection frequency, 3000 data are collected for each grating point of each FBG stress sensor 3, and 3x3000 data are collected for different wavebands of each sensor, that is, the original data matrix X1, Y1 and Z1 are obtained; .
[0046] 2. Noise filtering processing is performed on the collected data, sliding average filtering method is adopted, local average is used to suppress high-frequency random noise, while the overall trend of the signal is retained; for each data point, the arithmetic mean of the previous and subsequent 5 sampling points (n=5) is taken to replace the current point value as the filtered value of the current point.
[0047] For any element ( ) in the X1 matrix, the filtered value is : ; ; The X2 matrix formed by is the filtering matrix, and Y2 and Z2 are constructed in the same way.
[0048] 3. The strain average value of the data points of the different wavebands of the three FBG stress sensors 3 in the steady state period is taken, and the last 10s of data is selected according to the synchronously collected wind speed.
[0049] ; The steady-state matrix is formed, and X3 and X4 are constructed in the same way.
[0050] 4. Calculate the wavelength shift Δλ = steady-state matrix - initial value matrix, i.e. Δλ x , Δλ y , Δλ z, Δλ x = X3 - X0 1000×3 ; Δλ y = Y3 - Y0 1000×3 ; Δλ z = Z3 - Z0 1000×3 ; .
[0051] 5, the strain sensitivity coefficient K e Convert Δλ to strain value: ε = Δλ / K e ; K e Determination by calibration test: FBG stress sensor 3 and resistance strain gauge are installed on the surface of the special-shaped conductor 10 test piece at the same time, the bending displacement is loaded to 500με in stages, the slope of the strain-wavelength shift curve is fitted to obtain K e Value, Ke = 1.2pm / με.
[0052] ; Take the average strain value of the steady-state period of the data points of the different wave bands of the three FBG strain sensors respectively, and select the data of the last 10s according to the synchronous collection of wind speed: .
[0053] Embodiment 3: The application also discloses a computer readable storage medium, which stores a computer program, and the computer readable storage medium stores a computer program, when the computer program is executed by a processor, the computer program can realize a special-shaped conductor 10 surface strain monitoring method based on a fiber Bragg grating (FBG) sensor, and specifically includes the implementation steps of the special-shaped conductor surface stress monitoring method disclosed in embodiment 2.
[0054] The storage medium includes but is not limited to the following implementation forms: 1. The standard storage unit integrated in the electronic device includes but is not limited to a hard disk storage, a random access memory (RAM), a read-only memory (ROM) and other semiconductor storage devices.
[0055] 2. The expandable external storage device specifically covers smart media cards conforming to the PCMCIA interface specification, secure digital storage cards conforming to the SD / MMC standard, USB flash drives and pluggable solid state hard disks and other removable storage carriers.
[0056] 3. The hybrid storage architecture simultaneously includes the combination of the internal storage unit and the external expansion storage device of the electronic device.
[0057] The storage function of the storage medium is specifically represented as: 1. The computer executable instruction set and related system program number are stored persistently.
[0058] 2. The input and output data stream in the dynamic cache processing procedure, including the generated monitoring data to be transmitted and the computing intermediate result to be processed.
[0059] 3. The multi-thread concurrent access mechanism is supported, meeting the data throughput demand of the real-time monitoring system.
[0060] The technical scheme of the present application effectively solves the technical problems of data storage reliability, storage carrier compatibility and real-time data processing efficiency in the strain monitoring system of the special-shaped wire 10 through the innovative storage medium architecture design.
[0061] Embodiment 4: The present application also discloses a computer device, which is constituted as follows: 1. The hardware architecture includes a processor unit, a memory module and a computer executable program stored on the memory, and the processor is configured to execute the program to realize the monitoring method based on the monitoring of the surface strain of the special-shaped wire 10, specifically including the specific steps of the FBG stress sensor 3 selection and the flexible substrate 4 structure design in embodiment 2, the establishment of the monitoring system of the surface strain of the special-shaped wire 10 and the surface strain collection and data processing of the special-shaped wire 10.
[0062] 2. The core operation unit of the processor includes but is not limited to: (1) general-purpose processor: central processing unit (CPU), microcontroller (MCU), embedded processor; (2) special-purpose processor: digital signal processor (DSP), application-specific integrated circuit (ASIC); (3) programmable logic device: field programmable gate array (FPGA), complex programmable logic device (CPLD).
[0063] 3. The memory includes a combination architecture of static memory and dynamic memory; (1) non-volatile storage unit: read-only memory (ROM), flash memory, used for solidifying the basic instruction set; (2) volatile storage unit: random access memory (RAM), cache memory, used for dynamically loading operation data; (3) extended storage interface: extended storage controller supporting external disk array and optical storage device.
[0064] 4. The execution code form of the computer program is stored in the computer readable medium, including: (1) storage medium type: magnetic storage medium (hard disk, magnetic tape), optical storage medium (CD-ROM, DVD), semiconductor storage medium (SSD, UFS); (2) implementation: the machine instruction generated by compiling controls the processor to execute the above defined data processing flow, including the sensor size modeling, surface strain monitoring collection and analysis flow and the algorithm of converting the central wavelength into strain.
[0065] According to the shape of the outer surface of the profiled wire 10, a flexible base 4 is designed to fix the FBG stress sensor 3. Compared with the gluing process of the FBG fiber grating sensor and the measured structure, the technical scheme can avoid the adverse effect on the surface of the measured structure when monitoring the stress. The surface stress collection scheme and analysis method of the profiled wire 10 can be used in the wind tunnel test for monitoring the surface stress of the wire, realizing the steady-state data collection and analysis, and improving the accuracy of stress analysis. The heterogeneous processor cooperative architecture is adopted to realize the efficient distribution of sensor parameter calculation tasks, solve the computing power problem of the traditional single processor in complex mechanical modeling, and ensure the real-time performance and power-off data integrity of large-scale simulation data processing through the mixed design of dynamic storage management and non-volatile storage.
[0066] The above is the preferred embodiment of the present application. It should be pointed out that for ordinary skilled persons in the art, without departing from the principles of the present application, a number of improvements and refinements can be made, which should be considered as the protection scope of the present application.
Claims
1. A profiled conductor surface stress monitoring system, characterized by, The utility model relates to a FBG strain sensor for monitoring the stress of overhead transmission line, including: a strain sensing acquisition module (1) comprising a semicircular flexible substrate (4), a FBG stress sensor (3) embedded in the flexible substrate (4), and an insulating band (5) for fixing the flexible substrate (4); a strain signal analysis module (2) comprising a fiber grating demodulator (7) and a computer (8); wherein the inner surface profile (41) of the flexible substrate (4) matches the outer surface geometric parameters of the special-shaped conductor (10), and three semicircular through holes (42) are provided in the flexible substrate (4) for embedding the FBG stress sensor (3), and square through holes (43) are provided on both sides of the flexible substrate (4) for the insulating band (5) to pass through.
2. The profiled conductor surface stress monitoring system of claim 1, wherein, The material of the flexible substrate (4) is Flexible 50A resin, and the parameters of the inner surface profile (41) include a groove width a = 2.5 mm, a groove depth b = 1.6 mm, a fillet radius c = 0.5 mm, and a transition fillet radius z = 1.5 mm. The thickness of the flexible substrate (4) is 1.3-2.5 mm, and the width d is greater than the FBG grating segment length plus twice the insulating band width.
3. The profiled wire surface stress monitoring system of claim 1, wherein, The number of FBG stress sensors (3) is three, and the grating region length is 6 mm, and the center wavelengths are 1535 nm, 1545 nm, and 1555 nm, respectively. The three FBG stress sensors (3) are symmetrically distributed along the conductor axial spacing of 7.5 meters, and the second FBG stress sensor (3) is located at the midpoint of the conductor.
4. A monitoring method of a monitoring system as claimed in any one of claims 1 to 3, characterized in that The method comprises the following steps: Step 1: sensor selection and structure design; Step 2: 3D printing of the flexible substrate; Step 3: building a stress monitoring system; Step 4: collecting center wavelength data; Step 5: data processing to obtain strain value.
5. The monitoring method of the monitoring system according to claim 4, characterized by, Step 1 includes: determining the positioning size of the semicircular through hole (42) through fluid-structure coupling simulation: 0.25 mm from the inner surface of the flexible substrate (4) and located on the split surface centerline; determining the positioning size of the square through hole (43) through statics simulation: 1 mm from the bottom of the cross section and 2.1 mm from the side, with a size width e = 5 mm and a height f = 1 mm.
6. The monitoring method of a monitoring system according to claim 4, characterized by, Step 3 includes: connecting the FBG stress sensor (3) to the fiber grating demodulator (7) through the fiber jumper (6); the fiber jumper (6) is provided with fiber flanges at both ends, and the connection interfaces are cleaned with anhydrous alcohol.
7. The monitoring method of the monitoring system according to claim 4, characterized by, In step 4, the initial value matrix X0, Y0, Z0 of the center wavelength of each monitoring point of the three FBG stress sensors (3) is collected and recorded; 。 8. The monitoring method of the monitoring system according to claim 4, characterized by, The specific steps of step 5 are as follows: Step 51: collecting the center wavelength original data matrix X1, Y1, Z1 of 100 Hz frequency within 30 seconds; ； Step 52: generating the filter matrix X2, Y2, Z2 by using the sliding average filter with a window size n = 5; Step 53: taking the last 10 seconds of steady-state data to calculate the wavelength mean matrix X3, Y3, Z3; Step 54: Calculate the wavelength shift Δλ = steady state matrix - initial value matrix, i.e. Δλ x , Δλ y , Δλ z , Δλ x = X3- X0; Δλy= Y3- Y0, Δλz= Z3- Z0; ； Step 55: use the strain sensitivity coefficient K e Convert Δλ to strain value: ε = Δλ / K e ; the K e Determined by calibration test: install FBG stress sensor (3) and resistance strain gauge on the surface of profiled conductor (10) sample synchronously, load bending displacement to 500με in stages, fit the slope of strain-wavelength shift curve to obtain K e value.
9. A computer-readable storage medium having stored thereon a computer program, characterized in that, The program is executed by the processor to realize the steps of the FBG strain sensor monitoring method according to claim 4.
10. A computer device comprising a memory, a processor and a computer program (9) stored on the memory, characterized in that, The processor executes the program to realize the steps of the FBG strain sensor monitoring method according to claim 4.