Wind power tower multidirectional strain monitoring device based on fiber bragg grating

Abstract

The utility model provides a wind power tower multidirectional strain monitoring device based on fiber bragg gratings, and relates to the technical field of wind power tower monitoring. Comprising a decagonal mounting shell, a strain sensor center pile and a plurality of insertion piles, the mounting shell is composed of a bottom shell, a top shell and ten connecting plates, the center pile is arranged in the center of the bottom shell, and insertion openings are formed in the side edges of the center pile. The splicing piles are hollow cuboids, grating strings are arranged in the splicing piles, and the two ends of each splicing pile are optically connected with the center pile and the adjacent splicing piles through splicing plugs respectively, so that 360-degree all-circumferential strain monitoring is achieved. The device adopts an all-fiber, passive and modular design, is convenient to install, anti-interference and maintenance-free, and is suitable for distributed strain monitoring of the wind power tower.

Description

Technical Field

[0001] This utility model relates to the field of wind turbine tower monitoring technology, specifically to a multi-directional strain monitoring device for wind turbine towers based on fiber optic gratings. Background Technology

[0002] Existing wind turbine tower strain sensors can only monitor strain changes at the sensor installation point and cannot perform multi-directional detection. To improve monitoring accuracy and range, existing tower strain monitoring systems sometimes require the installation of large quantities of strain sensors, significantly increasing monitoring costs. Furthermore, most existing tower strain monitoring systems use electronic strain sensors, which are susceptible to interference from internal tower electronics and require active power. Utility Model Content

[0003] To address these issues, this invention provides a multi-directional strain monitoring device for wind turbine towers based on fiber optic gratings, which solves the problems of insufficient monitoring accuracy, high monitoring costs, and environmental impact associated with existing equipment.

[0004] To achieve the above objectives, this utility model provides the following technical solution: a multi-directional strain monitoring device for wind turbine towers based on fiber Bragg gratings, comprising:

[0005] The mounting housing includes a strain sensor bottom shell, a connecting plate, and a strain sensor top shell. The strain sensor bottom shell and the strain sensor top shell have the same shape. The connecting plate is located at the upper edge of the strain sensor bottom shell. The two ends of the connecting plate are respectively connected to the strain sensor bottom shell and the strain sensor top shell. The connecting plate has several hollow holes.

[0006] A strain sensor center post is located at the center above the strain sensor base shell, and a wire harness tube is provided on the top of the strain sensor center post.

[0007] The connector is provided in several parts, and the connector can be detachably connected to the central pile of the strain sensor through the hole.

[0008] Preferably, the connector is configured as a hollow cuboid, with a rubber sleeve and a first connector at one end and a second connector at the other end.

[0009] Preferably, the connector is provided with a plurality of limiting buckles, which are symmetrically arranged.

[0010] Preferably, a grating string is provided inside the connector, and the grating string is fixed between the limiting buckles.

[0011] Preferably, the two ends of the grating string have tail optical fibers, one end of which passes through the rubber tube and is connected to the first connector, and the other end of which is connected to the second connector.

[0012] Preferably, the bottom shell and the top shell are decagonal, the connecting plate is vertically arranged, and the connecting plate has ten surfaces.

[0013] Preferably, the strain sensor center pile is configured as a decagonal pile body, and each side of the strain sensor center pile corresponds to each surface of the connecting plate.

[0014] Preferably, each side of the central pile of the strain sensor is provided with a connector.

[0015] Preferably, the tail fiber is connected to the connector via the second connector using an optical routing method.

[0016] Preferably, the top shell is provided with a hole larger than the diameter of the wire harness tube.

[0017] The application employs the above technical solution and has at least the following beneficial effects:

[0018] The decagonal symmetrical layout enables 360° full-circumference monitoring; the plug-in structure facilitates installation, maintenance, and expansion; the all-fiber passive solution is maintenance-free, interference-resistant, and suitable for harsh wind power environments; the modular design allows for stacking arrangements according to tower height, providing strong scalability.

[0019] It should be understood that the above general description and the following detailed description are exemplary and explanatory only, and do not limit this application. Attached Figure Description

[0020] To more clearly illustrate the technical solutions in the embodiments of this utility model or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0021] Figure 1 This is a structural schematic diagram provided by an embodiment of the present utility model;

[0022] Figure 2 This is a structural schematic diagram provided by an embodiment of the present utility model;

[0023] Figure 3 This is a schematic diagram of the splice pile structure provided in an embodiment of this utility model;

[0024] In the diagram: 1. Strain sensor bottom shell; 2. Connecting plate; 3. Strain sensor top shell; 4. Strain sensor center stake; 5. Wiring harness tube; 6. Connector stake; 7. Rubber sleeve; 8. First connector; 9. Second connector; 10. Limiting buckle; 11. Grating string. Detailed Implementation

[0025] To make the objectives, technical solutions, and advantages of this utility model clearer, the technical solutions of this utility model will be described in detail below. Obviously, the described embodiments are only a part of the embodiments of this utility model, and not all of them. Based on the embodiments of this utility model, all other implementation methods obtained by those skilled in the art without creative effort are within the scope of protection of this utility model.

[0026] A specific embodiment of this utility model provides a multi-directional strain monitoring device for wind turbine towers based on fiber Bragg gratings, combined with the attached... Figure 1 As shown, it mainly includes a mounting shell, a strain sensor center stake 4, and several connector stakes 6. The mounting shell consists of a strain sensor bottom shell 1, a connecting plate 2, and a strain sensor top shell 3, which together form a closed and detachable cavity for protecting and positioning internal optical components and circuitry. The strain sensor center stake 4 is located above the center of the bottom shell 1 and is connected to an external demodulation device through a wire harness tube 5. The connector stakes 6 pass through the perforated holes on the connecting plate 2 and achieve a detachable optical connection with the strain sensor center stake 4, thereby realizing multi-directional strain monitoring.

[0027] Specifically, both the strain sensor bottom shell 1 and the strain sensor top shell 3 are decagonal flat plate structures with identical shapes. The connecting plate 2 is vertically set at the upper edge of the bottom shell 1 and connects the strain sensor bottom shell 1 and the strain sensor top shell 3 at both ends, forming ten continuous plate surfaces. Each plate surface has a rectangular hollow hole in the center for the insertion and placement of the plug 6. The strain sensor top shell 3 has a circular hole in the center with a diameter slightly larger than the outer diameter of the wire harness tube 5, allowing the wire harness tube 5 to pass upward and connect to the external fiber optic patch cord or demodulator, while ensuring that the top shell 3 can be freely installed and removed without interfering with the internal wiring.

[0028] Specifically, the strain sensor center pile 4 is a decagonal column with the same number of surfaces as the connecting plate 2, and each side of it is provided with a connector for docking with the second connector 9 of the connector pile 6; the wire harness tube 5 is used to thread the combined tail optical fiber and is connected to the external demodulation equipment through the optical fiber flange; for easy positioning.

[0029] Specifically, the connector 6 has a hollow rectangular structure. In this embodiment, the wall thickness is set in the range of 1-2mm, which can reduce weight and facilitate heat dissipation. One end is provided with a rubber sleeve 7 and a first connector 8, and the other end is provided with a second connector 9. The rubber sleeve 7 is used to protect the tail optical fiber that passes through the connector 6 and plays a role in dustproofing, waterproofing, and bending prevention. Several limiting buckles 10 are symmetrically arranged on both sides inside the connector 6. The grating string 11 is firmly clamped by the limiting buckles 10 to ensure that the grating string 11 does not slip or twist during transportation, installation, and long-term operation. The grating string 11 has two tail optical fibers leading out from both ends. One end of the tail optical fiber passes through the rubber sleeve 7 and the first connector 8 in sequence to form a free end, which is used to fusion splice with the previous stage connector or external extension optical fiber. The other end of the tail optical fiber is fusion spliced ​​and fixed with the second connector 9, and the optical routing connection is realized through the connector corresponding to the strain sensor center pile 4. In this embodiment, in order to improve the sealing level, a sealing ring or potting compound is provided between the second connector 9 and the connector of the strain sensor center pile 4 to meet the requirements of harsh working conditions such as humidity and salt spray inside the wind turbine tower.

[0030] In one feasible embodiment, the plug 6 eliminates the limiting buckle 10, and the grating string 1 is initially fixed to the strain sensor base plate 3 with epoxy resin glue at 80 degrees Celsius for 20 minutes. After the glue and the base material have cured, the material is allowed to cool naturally at room temperature, and then silicone glue is used to cover the epoxy resin glue to provide protection.

[0031] Working principle:

[0032] When the wind turbine tower is subjected to wind loads, earthquakes, or mechanical vibrations, the deformation of the tower surface is transmitted to the mounting shell and then to the connector 6, causing Bragg wavelength drift in the grating strings 11. The demodulation equipment acquires the wavelength signals returned by each grating string 11 in real time, and uses algorithms to invert the strain values ​​in each direction, realizing distributed strain monitoring of the entire circumference and multiple layers of the tower. Due to the use of an all-fiber optic solution, no on-site power supply is required, the electromagnetic interference resistance is strong, and dozens of grating strings 11 can be connected in series on a single optical fiber, which greatly reduces the number of sensors and wiring complexity, and significantly reduces monitoring costs.

[0033] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this utility model, and are not intended to limit it. Although this utility model 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. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of this utility model.

Claims

1. A multi-directional strain monitoring device for wind turbine towers based on fiber Bragg gratings, characterized in that, include: The mounting housing includes a strain sensor bottom shell (1), a connecting plate (2), and a strain sensor top shell (3). The strain sensor bottom shell (1) and the strain sensor top shell (3) have the same shape. The connecting plate (2) is located at the upper edge of the strain sensor bottom shell (1). The two ends of the connecting plate (2) are respectively connected to the strain sensor bottom shell (1) and the strain sensor top shell (3). The connecting plate (2) has several hollow holes. The strain sensor center post (4) is located at the center above the strain sensor bottom shell (1), and a wire harness tube (5) is provided on the top of the strain sensor center post (4). Connecting stake (6), several connecting stakes (6) are provided, and the connecting stakes (6) can be detachably connected to the strain sensor center stake (4) through the hole.

2. The multi-directional strain monitoring device for wind turbine towers based on fiber Bragg gratings according to claim 1, characterized in that: The connector (6) is configured as a hollow cuboid. One end of the connector (6) is provided with a rubber sleeve (7) and a first connector (8), and the other end of the connector (6) is provided with a second connector (9).

3. The multi-directional strain monitoring device for wind turbine towers based on fiber Bragg gratings according to claim 2, characterized in that: The connector (6) is provided with a number of limiting buckles (10), which are symmetrically arranged.

4. The multi-directional strain monitoring device for wind turbine towers based on fiber Bragg gratings according to claim 3, characterized in that: The connector (6) is provided with a grating string (11), which is fixed between the limiting buckles (10).

5. The multi-directional strain monitoring device for wind turbine towers based on fiber Bragg gratings according to claim 4, characterized in that: The two ends of the grating string (11) have tail optical fibers. One end of the tail optical fiber passes through the rubber tube sleeve (7) and is connected to the first connector (8). The other end of the tail optical fiber is connected to the second connector (9).

6. The multi-directional strain monitoring device for wind turbine towers based on fiber Bragg gratings according to claim 5, characterized in that: The strain sensor bottom shell (1) and the strain sensor top shell (3) are configured as decagons, the connecting plate (2) is vertically arranged and the connecting plate (2) is provided with ten plate surfaces.

7. The multi-directional strain monitoring device for wind turbine towers based on fiber Bragg gratings according to claim 6, characterized in that: The strain sensor center pile (4) is configured as a decagonal pile body, and each side of the strain sensor center pile (4) corresponds to each plate surface of the connecting plate (2).

8. The multi-directional strain monitoring device for wind turbine towers based on fiber Bragg gratings according to claim 7, characterized in that: Each side of the strain sensor center pile (4) is provided with a connector.

9. A multi-directional strain monitoring device for wind turbine towers based on fiber Bragg gratings according to claim 8, characterized in that: The tail fiber is connected to the connector via the second connector (9) using an optical routing method.

10. A multi-directional strain monitoring device for wind turbine towers based on fiber Bragg gratings according to claim 9, characterized in that: The strain sensor top shell (3) is provided with a hole larger than the diameter of the wire harness tube (5).

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