CN212007596U - Calibration device of multi-measuring-point fiber grating high-temperature sensor - Google Patents

Abstract

The utility model provides a calibration device of multiple measuring points fiber grating high temperature sensor. The calibration device comprises a thermocouple temperature acquisition module, an optical fiber wavelength acquisition module and a high-temperature tubular furnace arranged on a rail-mounted moving platform, wherein when calibration is carried out, a reference thermocouple is fixed at each measuring point of the multi-measuring-point FBG high-temperature sensor and is bound with a traction metal wire to form an optical fiber thermocouple binding structure, and the optical fiber thermocouple binding structure penetrates through the high-temperature tubular furnace and is always in a straightening state; the high-temperature tube furnace moves along the optical fiber thermocouple binding structure, and simultaneously acquires the optical wavelength value of each measuring point and the temperature value measured by the reference thermocouple of the measuring point through the thermocouple temperature acquisition module and the optical fiber wavelength acquisition module to realize the temperature calibration process. The utility model discloses an in the operating temperature and the design length within range of device, provide accurate, convenient wavelength temperature coefficient to the FBG temperature sensor of a plurality of measurement stations and mark, improve the measuring precision of sensor.

Description

Calibration device of multi-measuring-point fiber grating high-temperature sensor

Technical Field

The utility model belongs to the optical fiber sensing field relates to a calibration device of multiple measuring point fiber grating (FBG) high temperature sensor.

Background

Since the advent of FBG temperature sensors, FBG temperature sensors have been widely used in the fields of power systems, civil engineering, chemical engineering, aerospace, medical care and the like, due to their advantages of compact structure, small volume, convenient layout, anti-electromagnetic interference, high accuracy, good durability, and being capable of being both surface-bonded and layout inside equipment.

The FBG temperature sensor realizes temperature measurement through the approximately linear relationship between the optical wavelength and the temperature, most of the engineering application of the FBG temperature sensor focuses on the measurement in the temperature range of-20-80 ℃, a small part of the FBG temperature sensor can be applied to the temperature measurement below 300 ℃, and the temperature measurement above 300 ℃ has almost no engineering application. Besides being limited by temperature tolerance brought by an optical fiber coating layer, FBG grating writing, a packaging mode and the like, wavelength temperature coefficient calibration of the multi-point FBG high-temperature sensor is also a difficulty in limiting engineering application of the multi-point FBG high-temperature sensor. Generally, the length of an effective heat source region of a high-temperature furnace is far lower than that of an FBG array with multiple measuring points, so that the temperature coefficients of the FBG measuring points cannot be calibrated at the same time; and the separate calibration is time-consuming, and the temperature field of each FBG and the temperature calibration source can not be kept consistent, so that calibration error factors are added, and the temperature measurement precision of the sensor is reduced.

With the technological innovation of the writing and packaging modes of the FBG grating, the FBG high-temperature sensor is gradually applied to a high-temperature environment above 300 ℃ by scientific research institutions; meanwhile, the yield and the application requirements of the multi-point FBG high-temperature sensor array are higher and higher, so that a calibration device aiming at the multi-point FBG high-temperature sensor is urgently needed to calibrate the wavelength and temperature relation curve of the FBG temperature sensor.

The utility model provides a calibration device and method of multiple measurement station FBG high temperature sensor can provide accurate, convenient temperature to the FBG temperature sensor of a plurality of measurement stations and mark at the operating temperature and the design length within range of device.

Disclosure of Invention

In order to solve the difficult problem that many measurement stations FBG high temperature sensor lacks accurate, convenient wavelength temperature coefficient calibration device and method, the utility model provides a calibration device of many measurement stations FBG high temperature sensor can provide accurate, convenient wavelength temperature coefficient to the FBG temperature sensor of a plurality of measurement stations and mark in the operating temperature and the design length scope of device, improves the measuring precision of sensor.

In order to achieve the purpose, the technical scheme of the utility model is a calibration device of a multi-measuring-point fiber grating high-temperature sensor, which comprises a high-temperature tube furnace, a track-type mobile platform, a fiber thermocouple binding structure and a demodulation control module; the high-temperature tube furnace is arranged on a moving platform of the rail-type moving platform and moves left and right along a sliding rail of the rail-type moving platform under the action of the moving platform; the system comprises a rail-type mobile platform, a high-temperature tube furnace, a plurality of fiber thermocouple binding structures, a plurality of high-temperature tube furnace guide wires and a plurality of high-temperature tube furnace guide wires, wherein a first sensor bracket and a second sensor bracket which are on the same straight line with the high-temperature tube furnace are symmetrically arranged on two sides of the rail-type mobile platform; one end of a traction metal wire of the optical fiber thermocouple binding structure is fixed on the first sensor bracket, and the other end of the traction metal wire together with the plurality of bundled reference thermocouples and the multi-measuring point FBG high-temperature sensor penetrates through the high-temperature tubular furnace and then is fixed on the second sensor bracket, and the optical fiber thermocouple binding structure is kept in a straightening state all the time; the demodulation control module comprises thermocouple temperature acquisition modules respectively connected with a plurality of reference thermocouples in a signal mode and an optical fiber wavelength acquisition module in signal connection with the multi-point FBG high-temperature sensors, the thermocouple temperature acquisition modules are used for acquiring temperature values measured by the reference thermocouples, and the optical fiber wavelength acquisition modules are used for acquiring optical wavelength values measured by the multi-point FBG high-temperature sensors.

The utility model discloses further technical scheme: the demodulation control module also comprises a control terminal and a mobile control module, and the mobile control module is used for driving the mobile station to move bidirectionally along the slide rail; the thermocouple temperature acquisition module, the optical fiber wavelength acquisition module and the mobile control module are respectively in communication connection with the control terminal; the control terminal is used for controlling each module and displaying the temperature value collected by the calibration thermocouple temperature collection module and the optical wavelength value collected by the optical fiber wavelength collection module.

The utility model discloses further technical scheme: the high-temperature tube furnace comprises a quartz tube, a heating wire wound on the outer wall of the quartz tube, a hearth heat-insulating layer wrapped outside the quartz tube and the heating wire and a temperature control module, wherein furnace plugs are respectively arranged at two ends of the quartz tube; the temperature control module comprises a temperature measuring thermocouple and a heating feedback control display system, the furnace plug is made of heat-insulating ceramics, a through hole is formed in the center of the ceramic furnace plug, and the optical fiber thermocouple binding structure penetrates through the through hole of the ceramic furnace plug at one end of the furnace plug to enter the high-temperature tube furnace and penetrates out of the through hole of the ceramic furnace plug at the other end of the furnace plug.

The utility model discloses further technical scheme: the first sensor bracket is a fixed bracket, and the top end of the first sensor bracket is provided with a clamping mechanism for fixing one end part of the traction metal wire; the second sensor support is a pulley support, a pulley is arranged at the top end of the second sensor support, the other end of the traction metal wire is fixedly connected with a balancing weight after winding around the pulley at the upper end of the second sensor support, and the optical fiber thermocouple binding structure is always in a straightened state by utilizing the gravity of the balancing weight.

The utility model discloses better technical scheme: the traction metal wire, the plurality of reference thermocouples and the multi-measuring-point FBG high-temperature sensor are bundled together through the binding metal wire, and the multi-measuring-point FBG high-temperature sensor is arranged at the central position and is on the same straight line with the central axis of the high-temperature tubular furnace; the plurality of reference thermocouples all meet the temperature calibration source requirements.

The utility model discloses further technical scheme: the rail type mobile platform comprises a rail base, a sliding rail and a mobile station; the sliding rail is an optical axis sliding rail formed by a pair of metal rod pieces, and two ends of the sliding rail are fixed on the rail base; the bottom of the moving platform is provided with a pulley matched with the optical axis slide rail, the moving platform is connected with the slide rail in a sliding way through the pulley and can move left and right on the slide rail, and the high-temperature tube furnace is arranged on the moving platform through a three-dimensional adjusting frame; the mobile control module drives the mobile platform to drive the high-temperature tube furnace to move in two directions along the optical axis slide rail.

The utility model discloses better technical scheme: the highest working temperature of the high-temperature tube furnace is more than 1000 ℃; the hearth heat-insulating layer is formed by pressing ceramic fiber materials, the heating wires are alloy heating wires, and the heating wires are spirally wound outside the quartz tube.

The utility model has the advantages that:

(1) the utility model discloses a fixed reference thermocouple in each measurement station position of multiple measurement station FBG high temperature sensor through the mode of tying up, then guarantee that multiple measurement station FBG high temperature sensor and a plurality of reference thermocouples are in the linear state all the time through the wire, then control high temperature tubular furnace and remove along multiple measurement station FBG high temperature sensor, and gather the wavelength of different measurement stations and correspond the temperature value of reference thermocouple simultaneously, thereby realize the calibration of the wavelength and the temperature of different measurement station positions, its calibration equipment is built conveniently, in a flexible way, can solve the calibration problem of wavelength and temperature relation curve of multiple measurement station FBG high temperature sensor;

(2) the utility model controls the movement of the high temperature tube furnace through the mobile platform, and can flexibly replace the length of the track base according to the length of the multi-measuring point FBG array so as to be suitable for the multi-measuring points of sensors with different lengths and measuring points;

(3) the utility model ensures that the fiber thermocouple is always in a straightened state by utilizing the gravity action of the balancing weight in the calibration process, avoids the bending stress interference caused by the thermal expansion of metal, and improves the temperature measurement precision of the multi-measuring-point FBG high-temperature sensor to be calibrated;

(4) the utility model discloses a removal module, wavelength collection and temperature acquisition all control and show through control terminal, make whole device realize automatic an organic whole to can realize automatic purpose of demarcation to its real time monitoring demarcating the in-process, improved and markd efficiency and accuracy.

The utility model provides a calibration device simple structure, build the convenience, its calibration method easy operation, positioning accuracy is high, has realized in the operating temperature and the design length within range of device, provides accurate, convenient wavelength temperature coefficient to the FBG temperature sensor of a plurality of measurement stations and marks, improves the measuring precision of sensor.

Drawings

Fig. 1 is a schematic structural diagram of the present invention;

FIG. 2 is a schematic structural view of the middle holding furnace of the present invention;

FIG. 3 is a cross-sectional view AA in FIG. 2;

FIG. 4 is a cross-sectional view of BB of FIG. 2;

FIG. 5 is a schematic structural view of a fiber thermocouple ligation structure according to the present invention;

FIG. 6 is a longitudinal sectional view of the fiber thermocouple ligation structure according to the present invention;

fig. 7 is a control schematic diagram of the present invention;

in the figure: 1-high temperature tube furnace, 11-hearth heat-insulating layer, 12-heating wire, 13-temperature control module, 14-quartz tube, 15-furnace plug, 16-furnace wall, 17-through hole; 2-rail type moving platform, 21-rail base, 22-slide rail, 23-moving platform; 3-a first sensor holder, 31-a clamping mechanism; 4, binding a fiber thermocouple, 41, a multi-measuring-point FBG high-temperature sensor, 42, a reference thermocouple, 43, a traction metal wire, 44, a binding metal wire and 45, an FBG measuring point; 5-demodulation control module, 51-mobile control module, 52-thermocouple temperature acquisition module, 53-optical fiber wavelength acquisition module, and 54-control terminal; 6-second sensor support, 61-pulley, 62-balancing weight.

Detailed Description

The present invention will be further explained with reference to the drawings and examples. Fig. 1 to 7 are drawings of the embodiment, which are drawn in a simplified manner and are only used for the purpose of clearly and concisely illustrating the embodiment of the present invention. The following detailed description of the embodiments of the present invention is presented in the drawings and is not intended to limit the scope of the invention as claimed. Based on the embodiments in the present invention, all other embodiments obtained by a person skilled in the art without creative efforts belong to the protection scope of the present invention.

In the description of the present invention, it is to be understood that the terms "upper", "lower", "inner", "outer", "left", "right", and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the drawings, or orientations or positional relationships that are conventionally placed when the products of the present invention are used, or orientations or positional relationships that are conventionally understood by those skilled in the art, and are merely for convenience of description of the present invention and simplifying the description, but do not indicate or imply that the device or element that is referred to must have a specific orientation, be constructed and operated in a specific orientation, and thus, should not be construed as limiting the present invention.

The embodiment I provides a calibration device of a multi-measuring-point fiber grating high-temperature sensor, which comprises a high-temperature tube furnace 1, a rail-type moving platform 2, a fiber thermocouple binding structure 4 and a demodulation control module 5, as shown in FIG. 1. The rail type mobile platform 2 comprises a rail base 21, a slide rail 22 and a mobile platform 23; the slide rail 22 is an optical axis slide rail formed by a pair of metal rod pieces, and two ends of the slide rail are fixed on the rail base 21; the bottom of the moving platform 23 is provided with a pulley matched with the optical axis slide rail 22, the moving platform 23 is connected with the slide rail 22 in a sliding way through the pulley, and the high-temperature tube furnace 1 is arranged on the moving platform 23 through the three-dimensional adjusting frame 7 and is driven by the moving platform 23 to move left and right along the slide rail 22. The three-dimensional adjusting frame 7 adopts the existing three-dimensional adjusting frame, can realize the fine adjustment of the transverse direction, the longitudinal direction and the height of the high-temperature tube furnace 11, and ensures that the axis of the high-temperature tube furnace 11 is parallel to the axis 22 of the slide rail. The first sensor support 3 and the second sensor support 6 which are arranged on the same straight line with the high-temperature tubular furnace 1 are symmetrically arranged on two sides of the rail type moving platform 2, the first sensor support 3 is a fixed support, the top end of the first sensor support is provided with a clamping mechanism 31 used for fixing one end part of a traction metal wire 43, the clamping mechanism 31 is composed of pressing plates of V-shaped grooves of different specifications, one end of the traction metal wire 43 can be embedded into the V-shaped groove, and the clamping mechanism is fixedly pressed through the pressing plates. Second sensor support 6 is the pulley support, is equipped with pulley 61 at its top, and second sensor support 6 still matches and is equipped with balancing weight 62.

The optical fiber thermocouple binding structure 4 in the first embodiment is as shown in fig. 5 and fig. 6, and includes a plurality of reference thermocouples 42 and a multi-point FBG high temperature sensor 41 fixed on a traction wire 43, the plurality of reference thermocouples 42 are correspondingly bound at each FBG measuring point 45 of the multi-point FBG high temperature sensor 41, the traction wire 43, the plurality of reference thermocouples 42 and the multi-point FBG high temperature sensor 41 are bound together by a binding wire 44 according to the layout requirement, and the multi-point FBG high temperature sensor 41 is arranged at the central position and is on the same straight line with the central axis of the high temperature tubular furnace 1; the plurality of reference thermocouples 42 all meet temperature calibration source requirements. The traction wire 43 is a stainless steel wire; the binding wires 44 are thin copper wires or iron wires. As shown in fig. 1, during calibration, one end of a traction wire 43 of the optical fiber thermocouple binding structure 4 is fixed on the first sensor bracket 3, the other end of the traction wire together with the bundled reference thermocouples 42 and the multi-measuring-point FBG high-temperature sensor 41 passes through the high-temperature tube furnace 1 and then is fixedly connected with a balancing weight 62 after being wound around a pulley 61 at the upper end of the second sensor bracket 6, and the optical fiber thermocouple binding structure 4 is always in a straightened state by utilizing the gravity of the balancing weight 62, so that the bending stress interference caused by metal thermal expansion is avoided, and the temperature measurement accuracy of the multi-measuring-point FBG high-temperature sensor to be calibrated is improved.

As shown in fig. 2, 3 and 4, the high-temperature tube furnace 1 in the first embodiment includes a quartz tube 14, a heating wire 12 wound on an outer wall of the quartz tube 14, a hearth insulating layer 11 wrapped outside the quartz tube 14 and the heating wire 12, a furnace wall 16 and a temperature control module 13, wherein furnace plugs 15 are respectively arranged at two ends of the quartz tube 14; the maximum working temperature of the high-temperature tubular furnace 1 is more than 1000 ℃. The hearth heat-insulating layer 11 is made of ceramic fiber materials such as alumina and zirconia; the heating wire 12 is formed by spirally winding alloy wires such as high-quality nickel-chromium, iron-chromium-aluminum and the like, the alloy wires are spirally wound outside the quartz tube 14, and the temperature control module 13 comprises a temperature measurement N-type thermocouple and a heating feedback control display system; the quartz tube 14 is a cylindrical thin-wall tube, the size of the quartz tube is designed according to the hearth and the insulating layer 11, and different specifications can be replaced; the furnace plug 15 is made of heat-insulating ceramics, and a through hole 17 is formed in the center of the ceramic furnace plug and used for distributing optical fibers or thermocouples to be calibrated. The optical fiber thermocouple binding structure 4 penetrates through the ceramic furnace plug through hole at one end of the high-temperature tube furnace to enter the high-temperature tube furnace and penetrates out of the ceramic furnace plug through hole at the other end of the high-temperature tube furnace. The furnace plug 15 is made of porous ceramic material, a through hole is arranged in the center of the furnace plug 15,

in the calibration device for a multi-measuring-point fiber grating high-temperature sensor provided in the first embodiment, as shown in fig. 1 and 7, the demodulation control module 5 includes a control terminal 54, a mobile control module 53, a thermocouple temperature acquisition module 51 and a fiber wavelength acquisition module 52, and the thermocouple temperature acquisition module 51 is respectively connected to signal lines of a plurality of reference thermocouples 42 and is configured to acquire temperature values measured by the plurality of reference thermocouples 42; the optical fiber wavelength acquisition module 52 is connected with the signal line of the multi-point FBG high-temperature sensor 41 and is used for acquiring the light wavelength value measured by the multi-point FBG high-temperature sensor 41. The thermocouple temperature acquisition module 51, the optical fiber wavelength acquisition module 52 and the mobile control module 53 are respectively in communication connection with a control terminal 54. The control terminal 54 is a computer with a display screen for controlling each module and displaying the calibration measurement result by software. The movement control module 53 drives the moving platform to drive the high-temperature tube furnace 1 to move bidirectionally along the optical axis slide rail 22 under the control of a computer.

The second embodiment provides a calibration method of a multi-point fiber bragg grating high-temperature sensor, the method comprises the steps of calibrating the multi-point fiber bragg grating high-temperature sensor by using the calibration device in the first embodiment, selecting an FBG high-temperature sensor array with 5 FBG measuring points 45 as a multi-point FBG high-temperature sensor 41 to be calibrated, enabling the interval between each temperature measuring point to be 50mm, selecting 5 primary-precision N-type thermocouples as a reference thermocouple 42, binding the centers of the FBG measuring points 45 and the top ends of the reference thermocouples 42 one by one as shown in FIGS. 5 and 6, annularly distributing 5 reference thermocouples 42 and 1 traction metal wire 43 with the multi-point FBG high-temperature sensor 41 as the center, and binding the multi-point FBG high-temperature sensor 41, the reference thermocouples 42 and the traction metal wire 43 together in a spiral line shape by using the binding metal; the FBG measurement point 45 is made using a femtosecond laser.

In the second embodiment, the maximum working temperature of the high temperature tube furnace 11 is 1200 ℃, the lengths of the heating and constant temperature regions are 100mm and 30mm respectively, the inner diameter and the length of the quartz tube 14 are phi 30mm and 110mm respectively, and the size of the central through hole of the furnace plug is phi 5 mm. The rail base 21 is a groove-type stainless steel base with the size of 2500mm multiplied by 110mm multiplied by 30 mm. The optical axis slide rail 22 is made of cylindrical stainless steel, is parallelly mounted on the rail base 21, and has the size phi 10mm multiplied by 2550 mm. The mobile platform 23 is a one-dimensional displacement platform with a slide rail, the maximum bearing weight of the one-dimensional displacement platform is 30KG, the displacement range is +/-500 mm, and the displacement precision is 1 mm. The first sensor support 3 is a metal fixture with adjustable height, the metal fixture is fixed and pulled by a screw jacking mode to pull the metal wire 43, V-shaped grooves with different specifications are formed in the fixture of the first sensor support 3, and the outer diameter of the metal wire can be clamped to be phi 1 mm-phi 4 mm. The second sensor support 6 selects a stainless steel fixed pulley support with adjustable height, the outer diameter phi of the pulley is 35mm, and the counter weight 62 selects a stainless steel weight with the weight of 200-2000 g. The motion control module 51 is selected to be a drive controller matched with the displacement table 23. The thermocouple temperature acquisition module 52 employs an 8-channel, 16-bit precision, 125mV voltage acquisition module. The optical fiber wavelength acquisition module 53 adopts an optical fiber grating demodulator with the spectral range of 1515-1595 nm and the wavelength precision of +/-5 pm. The control terminal 54 is a PC equipped with three module (displacement, fiber, thermocouple) driver software and is equipped with a display screen.

The specific calibration process in example two is as follows:

(1) marking the position of each FBG measuring point 45 of the multi-measuring-point FBG high-temperature sensor 41, arranging one reference thermocouple 42 in a close fit manner one by one, and binding and fixing the multi-measuring-point FBG high-temperature sensor 41, the reference thermocouple 42 and the traction wire 43 by using a binding wire 44 to form an optical fiber thermocouple binding structure 4 shown in the figures 5 and 6;

(2) as shown in fig. 1, the optical fiber thermocouple binding structure 4 in the step (1) passes through the central through hole of the furnace plug 15 at one side of the high-temperature tube furnace 11 to enter the furnace, and the traction wire 43 passes through the central through hole of the furnace plug 15 at the other side of the high-temperature tube furnace 11 to ensure that the optical fiber thermocouple binding structure can penetrate through the high-temperature tube furnace 11 and the central axes of the two coincide with each other, so that the high-temperature tube furnace 11 can smoothly move left and right along the axis of the optical fiber thermocouple binding structure;

(3) as shown in fig. 1, one end of a traction wire 43 of the fiber thermocouple binding structure 4 is pressed by a cover plate at the top of the first sensor support 3, and the other end of the traction wire 43 passes through a pulley 61 at the top of the second sensor support 6 and is fixed on a balancing weight 62, so that the traction wire 43 is always in a straightening state under the action of gravity of the balancing weight 62, and temperature measurement errors of a multi-point FBG high-temperature sensor 41 caused by bending strain in a calibration process are avoided;

(4) as shown in fig. 1, the lead wires of the multi-point FBG high temperature sensor 41 and the reference thermocouple 42 are respectively connected to the optical fiber wavelength acquisition module 53 and the thermocouple temperature acquisition module 52, the lead wire of the mobile station 23 is connected to the mobile control module 51, and the output of each module is connected to the computer control terminal 54; after each electronic device is powered on, testing software is started to check whether the data display of each instrument/device is normal; the optical fiber wavelength acquisition module 53 displays the wavelength value and the position of each FBG measuring point 45 of the multi-measuring-point FBG high-temperature sensor 41, the thermocouple temperature acquisition module 52 displays the temperature value and the position of each reference thermocouple 42, and the mobile control module 51 displays the relative position of the displacement table 23;

(5) selecting a calibration temperature point according to the specification of a relevant test standard, starting the high-temperature tube furnace 1, heating to a first temperature collection point, and preserving heat for a plurality of times until the heat in the furnace reaches a balance;

(6) selecting the middle position of an effective constant temperature area of the high-temperature tubular furnace 1 as an acquisition position, driving a displacement table 23 by computer software, moving the high-temperature tubular furnace 1 to align the acquisition position with a first FBG measuring point 45 of the multi-measuring-point FBG high-temperature sensor 41, preserving heat for a plurality of times, and respectively recording the wavelength value of the FBG measuring point 45 and the temperature value of a reference thermocouple 42 thereof after the temperature field is stabilized; then, the computer software drives the high-temperature tube furnace 1 to move by 50mm, so that the acquisition position of the high-temperature tube furnace is aligned to a second FBG measurement point 45, and after the temperature field is stabilized for a plurality of times, the acquisition of the corresponding wavelength value and the temperature value is completed; by analogy, the wavelength values of the 5 FBG measuring points 45 of the multi-measuring-point FBG high-temperature sensor 41 and the temperature values of the corresponding reference thermocouples 42 are acquired;

(7) and (3) heating the high-temperature tube furnace 1 to a second temperature acquisition point, preserving heat for a plurality of times until the heat in the furnace is balanced, repeating the step (6) to finish the data acquisition of the second temperature acquisition point, and finishing the data acquisition of all the temperature acquisition points by analogy, thereby finishing the temperature calibration process.

To sum up, the utility model lists an embodiment, nevertheless the utility model discloses not only be limited to above-mentioned embodiment, as long as reach with any same or similar means the technical effect of the utility model, all should belong to the utility model discloses the scope of protection.

Claims (7)

1. The utility model provides a calibration device of multiple measuring point fiber grating high temperature sensor which characterized in that: the calibration device comprises a high-temperature tube furnace (1), a rail-type moving platform (2), an optical fiber thermocouple binding structure (4) and a demodulation control module (5); the high-temperature tube furnace (1) is arranged on a moving platform (23) of the rail-type moving platform (2) and moves left and right along a sliding rail (22) of the rail-type moving platform (2) under the action of the moving platform (23); a first sensor bracket (3) and a second sensor bracket (6) which are in the same straight line with the high-temperature tubular furnace (1) are symmetrically arranged on two sides of the rail-type moving platform (2), the optical fiber thermocouple binding structure (4) comprises a plurality of reference thermocouples (42) and multi-measuring-point FBG high-temperature sensors (41) fixed on a traction metal wire (43), and the plurality of reference thermocouples (42) are correspondingly bound at each FBG measuring point (45) of the multi-measuring-point FBG high-temperature sensors (41); one end of a traction metal wire (43) of the optical fiber thermocouple binding structure (4) is fixed on the first sensor support (3), the other end of the traction metal wire together with the plurality of bundled reference thermocouples (42) and the multi-measuring-point FBG high-temperature sensor (41) penetrates through the high-temperature tubular furnace (1) and then is fixed on the second sensor support (6), and the optical fiber thermocouple binding structure (4) is kept in a straightening state all the time; the demodulation control module (5) comprises thermocouple temperature acquisition modules (51) in signal connection with the reference thermocouples (42) and optical fiber wavelength acquisition modules (52) in signal connection with the multi-point FBG high-temperature sensors (41), the thermocouple temperature acquisition modules (51) are used for acquiring temperature values measured by the reference thermocouples (42), and the optical fiber wavelength acquisition modules (52) are used for acquiring optical wavelength values measured by the multi-point FBG high-temperature sensors (41).

2. The calibration device of the multi-point fiber grating high-temperature sensor as claimed in claim 1, wherein: the demodulation control module (5) further comprises a control terminal (54) and a movement control module (53), and the movement control module (53) is used for driving the mobile station (23) to move bidirectionally along the slide rail (22); the thermocouple temperature acquisition module (51), the optical fiber wavelength acquisition module (52) and the mobile control module (53) are respectively in communication connection with the control terminal (54); the control terminal (54) is used for controlling each module and displaying the temperature value collected by the calibration thermocouple temperature collection module (51) and the light wavelength value collected by the optical fiber wavelength collection module (52).

3. The calibration device of the multi-point fiber grating high-temperature sensor as claimed in claim 1 or 2, wherein: the high-temperature tube furnace (1) comprises a quartz tube (14), a heating wire (12) wound on the outer wall of the quartz tube (14), a hearth heat-insulating layer (11) wrapped outside the quartz tube (14) and the heating wire (12), a furnace wall (16) and a temperature control module (13), wherein furnace plugs (15) are respectively arranged at two ends of the quartz tube (14); the temperature control module comprises a temperature measuring thermocouple and a heating feedback control display system, the furnace plug (15) is made of heat-insulating ceramics, a through hole (17) is formed in the center of the ceramic furnace plug, and the optical fiber thermocouple binding structure (4) penetrates through the ceramic furnace plug through hole at one end of the furnace plug to enter the high-temperature tubular furnace and penetrates out of the ceramic furnace plug through hole at the other end of the furnace plug.

4. The calibration device of the multi-point fiber grating high-temperature sensor as claimed in claim 1 or 2, wherein: the first sensor bracket (3) is a fixed bracket, and the top end of the first sensor bracket is provided with a clamping mechanism (31) for fixing one end part of a traction metal wire (43); the second sensor support (6) is a pulley support, a pulley (61) is arranged at the top end of the second sensor support, the other end of the traction metal wire (43) is fixedly connected with a balancing weight (62) after winding around the pulley (61) at the upper end of the second sensor support (6), and the optical fiber thermocouple binding structure (4) is always in a straightening state by utilizing the gravity of the balancing weight (62).

5. The calibration device of the multi-point fiber grating high-temperature sensor as claimed in claim 1 or 2, wherein: the traction metal wire (43), the multiple reference thermocouples (42) and the multi-measuring-point FBG high-temperature sensor (41) are bundled together through a binding metal wire (44), and the multi-measuring-point FBG high-temperature sensor (41) is arranged at the central position and is on the same straight line with the central axis of the high-temperature tubular furnace (1); the plurality of reference thermocouples (42) each meet temperature calibration source requirements.

6. The calibration device of the multi-point fiber grating high-temperature sensor as claimed in claim 2, wherein: the rail type mobile platform (2) comprises a rail base (21), a sliding rail (22) and a mobile platform (23); the slide rail (22) is an optical axis slide rail formed by metal rod pieces, and two ends of the slide rail are fixed on the rail base (21); the bottom of the moving platform (23) is provided with a pulley matched with the optical axis slide rail (22), the moving platform (23) is connected with the slide rail (22) in a sliding way through the pulley and can move left and right on the slide rail (22), and the high-temperature tube furnace (1) is arranged on the moving platform (23) through a three-dimensional adjusting frame (7); the mobile control module (53) drives the mobile platform to drive the high-temperature tube furnace (1) to move along the optical axis slide rail (22) in two directions.

7. The calibration device of the multi-point fiber grating high-temperature sensor as claimed in claim 3, wherein: the highest working temperature of the high-temperature tubular furnace (1) is more than 1000 ℃; the hearth heat-insulating layer (11) is formed by pressing ceramic fiber materials, the heating wires (12) are alloy heating wires, and the heating wires are spirally wound outside the quartz tube (14).

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