Packaging structure of range-extended high-temperature-resistant sensor and signal correction method

Abstract

The invention discloses a packaging structure of an extended-range high-temperature-resistant sensor and a signal correction method, and relates to the technical field of optical fiber optics and sensors.The packaging structure comprises a first heat insulation layer, a second heat insulation layer and a third heat insulation layer which are sequentially arranged, a groove is formed in the second heat insulation layer, and a temperature measurement sensor is arranged in the groove; firstly, a primary multi-layer heat insulation structure is formed; the second heat insulation layer is formed by polymerizing six fan-shaped cylinders in the same shape, the six fan-shaped cylinders in the same shape are polymerized to be formed by arranging aerogel, ceramic heat insulation tiles and a second vacuum layer in a staggered mode, and the materials of the fan-shaped cylinders at the opposite angles are the same; according to the design, a multi-layer and multi-layer heat insulation structure is formed, so that dissipated heat continuously keeps uniform and consistent during transmission, external heat is effectively prevented from being transmitted to the inside, the high-temperature-resistant sensor breaks through the temperature measurement limit of the fiber bragg grating, and meanwhile, high-speed thermal response occurs; therefore, the measurement precision of the high-temperature-resistant sensor is improved.

Description

Technical Field

[0001] The present invention relates to the technical field of fiber optics and sensors, and particularly relates to a packaging structure and signal correction method for an extended-range high-temperature-resistant sensor. Background Art

[0002] Temperature is an important parameter reflecting the intensity of molecular thermal motion in the state of a substance. As one of the most important physical quantities in daily life, too high or too low temperature will have a huge impact on human life; and the temperature sensor, as one of the core components for temperature signal monitoring and control, has been widely used in aerospace, weaponry, production and life, etc.; in the military field, the accurate temperature measurement of the gun barrel using a temperature sensor helps to improve the gun design and enhance the gun's striking ability; in the aerospace field, the accurate temperature control of key parts such as the combustion chamber and engine is beneficial to improving the performance of aerospace engines, increasing the service life, and reducing costs; in addition, temperature sensors also play an extremely important role in industrial production, household appliances, health detection and other aspects of production and life.

[0003] The methods for temperature sensors to measure temperature are divided into two types: non-contact temperature measurement method and contact temperature measurement method; the non-contact temperature measurement method mainly focuses on radiation temperature measurement, but the response time is slow, it is difficult to obtain the corresponding temperature information in a timely manner, and there will be a large deviation in the temperature measurement result; contact temperature measurement includes types such as thermocouples, thermal resistors, and fiber Bragg gratings, which can obtain temperature information quickly and accurately, but it needs to be in direct contact with the object to be measured. After the temperature inside the sensor reaches the same as the temperature of the measurement point, the temperature of the measurement point can be measured. Therefore, when the sensor measures temperature, it cannot break through its own temperature measurement limit.

[0004] At the present stage in the high-temperature field, for commonly used contact high-temperature-resistant sensors, when the sensor measures temperatures above 1000 °C, the cost of the high-temperature-resistant sensors used is relatively high, which is not conducive to engineering applications; thus, high-temperature packaging is required for high-temperature-resistant sensors so that they can be used for a long time in a high-temperature environment. However, the current packaging structure will inevitably affect the response time of the sensor to temperature, and there will also be a part of heat loss when the heat source temperature is transmitted to the inside of the sensor through the packaging structure, resulting in the difficulty for the high-temperature-resistant sensor to break through the temperature measurement limit of the fiber Bragg grating itself, and accompanied by the problem of slow thermal response speed, thereby making the overall measurement accuracy of the high-temperature-resistant sensor relatively low. Summary of the Invention

[0005] The embodiments of the present invention provide a packaging structure and signal correction method for an extended-range high-temperature-resistant sensor, which can solve the problems in the prior art that the current packaging means make it difficult for the high-temperature-resistant sensor to break through the temperature measurement limit of the fiber Bragg grating itself, and accompanied by the problem of slow thermal response speed, thereby making the overall measurement accuracy of the high-temperature-resistant sensor relatively low.

[0006] An embodiment of the present invention provides a packaging structure for an extended-range high-temperature-resistant sensor, which includes a first heat-insulating layer, a second heat-insulating layer, and a third heat-insulating layer arranged in sequence and sealed with a high-temperature-resistant adhesive. A groove for placing a temperature-measuring sensor is provided inside the second heat-insulating layer;

[0007] The second heat-insulating layer is formed by aggregating six identical columnar bodies with a sector-shaped cross-section into a cylindrical structure; the six columnar bodies are divided into three groups, which are two second vacuum layers, two aerogels, and two ceramic heat-insulating tiles respectively, and the six columnar bodies are arranged staggeredly, and the materials of a diagonal group of columnar bodies are the same;

[0008] The temperature-measuring sensor is arranged in a sleeve inside the groove of the second heat-insulating layer, and the tail fiber of the temperature-measuring sensor extends out from one end of the sleeve and passes through the third heat-insulating layer.

[0009] Preferably, ceramic sheets are provided at both ends of the second heat-insulating layer for fixing the six sector-shaped columnar bodies;

[0010] The first heat-insulating layer includes a first vacuum layer and a high-temperature-resistant layer arranged in sequence, and the high-temperature-resistant layer is fixed to the ceramic sheet on one side of the second heat-insulating layer;

[0011] The high-temperature-resistant layer is ceramic fiber, asbestos board or foam glass.

[0012] Preferably, the first heat-insulating layer, the second heat-insulating layer and the third heat-insulating layer are sealed in a housing with a high-temperature-resistant sealing adhesive, and a high-temperature-resistant sealing adhesive layer is formed between the housing and the first heat-insulating layer, the second heat-insulating layer and the third heat-insulating layer;

[0013] A calibration bottom cover is provided on the other side of the first heat-insulating layer, and a semi-circular groove is provided on the calibration bottom cover, and a K-type thermocouple is embedded in the semi-circular groove; a bottom cover is provided on the other side of the third heat-insulating layer, and the tail fiber of the temperature-measuring sensor passes through the bottom cover and extends;

[0014] The housing, the calibration bottom cover and the bottom cover are fixed by welding.

[0015] Preferably, both ends of the sleeve are fixed in the groove of the second heat-insulating layer with a high-temperature-resistant adhesive, and the sleeve is located at the intersection of six identical sector-shaped columnar bodies;

[0016] The high-temperature-resistant adhesive is a specific high-temperature-resistant ceramic adhesive or a metal high-temperature-resistant adhesive.

[0017] Preferably, the temperature-measuring sensor is an optical fiber engraved with a fiber grating or a thermocouple.

[0018] Preferably, the high-temperature-resistant sealing adhesive layer is a silicon-free high-temperature refractory sealing adhesive;

[0019] The third heat insulation layer uses a polyurethane foam board with a low thermal conductivity coefficient;

[0020] The outer shell, calibration bottom cover and bottom cover are replaced with 304 stainless steel, 310 stainless steel or ceramic according to environmental requirements.

[0021] An embodiment of the present invention further provides a signal correction method for an extended-range high-temperature sensor, including the following steps:

[0022] Perform temperature calibration on the fiber Bragg grating in the temperature measurement sensor to establish the relationship between the temperature change of the fiber Bragg grating and the wavelength drift amount, expressed as:

[0023] ΔT FBG = f(Δλ)

[0024] Where: ΔT FBG represents the temperature change amount of the bare grating; Δλ represents the wavelength drift amount of the bare grating;

[0025] Obtain the temperature change data of the target point and the measured point of the extended-range high-temperature sensor. The calibration data T sr of the measured point is the temperature data measured by the temperature measurement sensor, and the calibration data T st of the target point is the temperature data measured by the K-type thermocouple in the calibration bottom cover;

[0026] The calibration data T sr of the measured point is expressed as:

[0027] T sr = ΔT FBG + T 0

[0028] Where: T 0 represents the initial temperature of the current environment;

[0029] Substitute the calibration data T sr of the measured point into the heat balance equation to calibrate the calibration data T sr of the target point, and obtain the calibrated calibration data T st of the target point, and correct the actual measurement data according to the calibrated calibration data T st of the target point.

[0030] Preferably, the correction of the actual measurement data includes:

[0031] Substitute the calibration data T sr of the measured point and the calibration data T st of the target point into the heat balance equation to obtain the calibrated calibration data T st of the target point. The formula is:

[0032]

[0033] The unknown parameters in the heat balance equation are obtained by the least squares method: the response lag time τ, the thermal resistance parameter ξ, and the reference temperature T ref , and the unknown coefficient matrix of the heat balance equation is obtained, which is expressed as:

[0034] x = [τ, ξ + 1, ξ·T ref T =(B T B) -1 B T A

[0035] Place the high-temperature resistant sensor after temperature calibration in the environment to be measured, with the fiber Bragg grating closely attached to the point to be measured, and collect the actual measurement data T of the actual measurement point vr , and obtain the actual measurement data of the target point, that is, the temperature T of the point to be measured vt ; its formula is:

[0036]

[0037] Where: k represents the measurement time.

[0038] The embodiment of the present invention provides a packaging structure and a signal correction method for an extended-range high-temperature resistant sensor. Compared with the prior art, its beneficial effects are as follows:

[0039] In the present invention, a first heat insulation layer, a second heat insulation layer, and a third heat insulation layer are arranged in sequence, and a groove is provided inside the second heat insulation layer. The temperature measurement sensor is placed in the groove to first form a preliminary multi-layer heat insulation structure; then the second heat insulation layer is formed by aggregating six fan-shaped columns with the same shape. The aggregation of the six fan-shaped columns with the same shape is formed by arranging aerogel, ceramic heat insulation tiles, and a second vacuum layer in an alternating manner, and the materials of a set of diagonal fan-shaped columns are the same; this packaging design forms a multiple multi-layer heat insulation structure, so that when the dissipated heat is transmitted in the second heat insulation layer, it is slowly transmitted and evenly dispersed in the six fan-shaped columns with the same shape, namely aerogel, ceramic heat insulation tiles, and the second vacuum layer, and most of the heat is isolated, continuously maintaining the uniformity and consistency of a small amount of heat transmission, effectively blocking the external heat from transmitting to the inside, and the external heat does not affect the internal high-temperature sensor, enabling the high-temperature resistant sensor to break through the temperature measurement limit of the fiber Bragg grating itself and having a relatively high-speed thermal response during the temperature measurement process, thereby improving the measurement accuracy of the high-temperature resistant sensor.

[0040] Moreover, the present invention establishes a heat balance equation and pre-calibrates to obtain the unknown parameters of the equation to correct the actual measurement data, reducing the thermal hysteresis and thermal loss caused by the packaging structure, and further improving the response speed and measurement accuracy of the high-temperature resistant sensor. Description of the Drawings​

[0041] Figure 1 It is a front view structural schematic diagram of an encapsulation structure of an extended-range high-temperature-resistant sensor provided by an embodiment of the present invention;

[0042] Figure 2 It is a side view structural schematic diagram of an encapsulation structure of an extended-range high-temperature-resistant sensor provided by an embodiment of the present invention;

[0043] Figure 3 It is a top view structural schematic diagram of an encapsulation structure of an extended-range high-temperature-resistant sensor provided by an embodiment of the present invention;

[0044] Figure 4 It is a disassembled structural schematic diagram of a calibration bottom cover of an encapsulation structure of an extended-range high-temperature-resistant sensor provided by an embodiment of the present invention;

[0045] Figure 5 It is an overall disassembled schematic diagram of an encapsulation structure of an extended-range high-temperature-resistant sensor provided by an embodiment of the present invention.

[0046] Wherein: 1. Temperature measurement sensor, 12. Fiber Bragg grating, 13. Sleeve, 14. High-temperature-resistant glue, 2. First heat insulation layer, 21. First vacuum layer, 22. High-temperature-resistant layer, 3. Second heat insulation layer, 31. Ceramic sheet, 32. Second vacuum layer, 33. Aerogel, 34. Ceramic heat insulation tile, 4. Third heat insulation layer, 5. Outer shell, 6. Sealed high-temperature-resistant glue layer, 7. Calibration bottom cover, 71. K-type thermocouple, 711. Thermocouple temperature measurement point, 8. Bottom cover. Specific embodiments

[0047] In order to make the above objects, features, and advantages of the present invention more obvious and understandable, the specific embodiments of the present invention will be described in detail below with reference to the accompanying drawings. Many specific details are set forth in the following description in order to fully understand the present invention. However, the present invention can be implemented in many other ways different from those described herein, and those skilled in the art can make similar improvements without departing from the connotation of the present invention. Therefore, the present invention is not limited by the specific embodiments disclosed below.

[0048] See Figures 1 to 5 , an embodiment of the present invention provides an encapsulation structure of an extended-range high-temperature-resistant sensor, including: temperature measurement sensor 1, fiber Bragg grating 12, sleeve 13, high-temperature-resistant glue 14, first heat insulation layer 2, first vacuum layer 21, high-temperature-resistant layer 22, second heat insulation layer 3, ceramic sheet 31, second vacuum layer 32, aerogel 33, ceramic heat insulation tile 34, third heat insulation layer 4, outer shell 5, sealed high-temperature-resistant layer 6, calibration bottom cover 7, K-type thermocouple 71, thermocouple temperature measurement point 711, and bottom cover 8.

[0049] Among them, a groove is provided in the second heat insulation layer 3, and the temperature measuring sensor 1 is placed in the groove of the second heat insulation layer 3. The first heat insulation layer 2, the second heat insulation layer 3, and the third heat insulation layer 4 are sequentially placed from bottom to top. The combined structure is placed in the outer shell 5 and sealed with a heat-resistant sealant in a vacuum environment to form a heat-resistant sealant layer 6. A hole for the tail wire of the temperature measuring sensor 1 to extend out is provided on the bottom cover 8, and then the outer shell 5, the calibration bottom cover 7, and the bottom cover 8 are fixed by welding.

[0050] Among them, the first heat insulation layer 2 has two layers of thermal protection structures, which are, from bottom to top, the first vacuum layer 21 and the high-temperature resistant layer 22; the second heat insulation layer 3 is formed by aggregating six fan-shaped columns with exactly the same shape into a complete cylinder, and there are ceramic sheets 31 fixed on the top and bottom. One group of the diagonal materials of the six fan-shaped columns are the second vacuum layer 32, aerogel 33, and ceramic heat insulation tiles 34 respectively; the third heat insulation layer 4 is made of materials with a lower thermal conductivity such as polyurethane foam board, and the high-temperature resistant layer 22 is made of materials with higher temperature resistance such as ceramic fiber, asbestos board, or foam glass.

[0051] Among them, the temperature measuring sensor 1 is a contact temperature measuring sensor such as an optical fiber engraved with a fiber Bragg grating 12 or a thermocouple; when the temperature measuring sensor 1 is an optical fiber engraved with a fiber Bragg grating 12, one end of the tail fiber of the fiber Bragg grating 12 extends out from one end of the sleeve 13 and is fixed with a heat-resistant adhesive 14.

[0052] Among them, the first heat insulation layer 2, the second heat insulation layer 3, and the third heat insulation layer 4 are fixed to the inner wall of the outer shell 5 with a heat-resistant sealant, and the outer shell 5, the calibration bottom cover 7, and the bottom cover 8 are fixed by welding; the bottom cover 8 and the calibration bottom cover 7 are replaceable. A semi-circular groove is provided on the upper wall of the calibration bottom cover 7, and a K-type thermocouple 71 is embedded. The thermocouple temperature measuring point 711 is located at the center point of the calibration bottom cover 7. Then, the groove is filled with a heat-resistant sealant until it is flat; the heat-resistant sealant layer 6 is a silicon-free high-temperature refractory sealant, and the heat-resistant adhesive 14 is a specific high-temperature resistant ceramic adhesive or a metal high-temperature resistant adhesive; the materials of the outer shell 5, the calibration bottom cover 7, and the bottom cover 8 can be replaced with stainless steel 304, stainless steel 310, or ceramic according to environmental requirements.

[0053] The embodiment of the present invention also provides a signal correction method for an extended-range high-temperature resistant sensor, including the following steps:

[0054] Step S1: When the temperature measuring sensor 1 is an optical fiber engraved with a fiber Bragg grating 12, first perform temperature calibration on the bare optical fiber engraved with the fiber Bragg grating 12 to be encapsulated. The temperature sensitivity of the fiber Bragg grating 12 is obtained by performing a quadratic polynomial fitting on the temperature change - wavelength drift curve, and the relationship between the temperature change amount and the wavelength drift amount of the bare grating is obtained, which is expressed as:

[0055] ΔT FBG =f(Δλ)

[0056] Wherein: ΔT FBG represents the temperature change of the bare grating; Δλ represents the wavelength drift of the bare grating; the fiber grating is a type-I grating, a type-IIA grating, a type-II grating, a sapphire fiber substrate fiber grating or a thermally regenerated fiber grating.

[0057] Step S2: When the temperature measurement sensor 1 is an optical fiber engraved with the fiber grating 12, in order to protect the grating area from stress in the packaging structure, the grating is encapsulated with a sleeve; the optical fiber engraved with the fiber grating extends from one end of the sleeve 13, and the other end is inside the sleeve 13. It is required that the grating area is at the center of the sleeve. The grating area of the fiber grating 12 is smaller than the length of the sleeve 13, and the inner diameter of the sleeve 13 is slightly larger than the outer diameter of the optical fiber; high-temperature resistant glue is cured at both ends of the sleeve 13 to relatively fix the position of the sleeve 13 and the fiber grating 12, and the fiber grating 12 and the pigtail inside the sleeve 13 are in a relaxed state; the above high-temperature resistant glue is a specific high-temperature resistant ceramic adhesive or a metal high-temperature resistant glue, and the material of the sleeve 13 is a capillary corundum tube or a capillary steel tube.

[0058] Step S3: Add a high-temperature resistant heat insulation layer to reduce heat transfer and provide heat preservation and insulation; there are three heat insulation layers in total: the first heat insulation layer 2, the second heat insulation layer 3, and the third heat insulation layer 4 from bottom to top; there is a vacuum area below the first heat insulation layer 2, and materials with relatively high temperature resistance such as ceramic fiber, asbestos board or ceramic heat insulation tiles are used above it. While reducing heat transfer, it can withstand high temperatures of 1200°C to over 1500°C; the second heat insulation layer 3 is formed by aggregating six sector columns with exactly the same shape into a complete cylinder, and is fixed by two circular ceramic pieces at the top and bottom; for the six sector columns, every two are in a diagonal group, and the materials are vacuum, aerogel, and ceramic heat insulation tiles respectively; the temperature measurement sensor 1 is placed in a pre-processed groove in the second heat insulation layer 3, and the temperature measurement point of the sensor is located at the center point of the sector column aggregate. Heat reaches the middle layer after being reduced by the heat protection material of the first heat insulation layer 2 for heat transfer, and the heat transferred to the temperature measurement sensor is also reduced. It can withstand a maximum temperature of 900°C; the material of the third heat insulation layer 4 is a material with a relatively low thermal conductivity such as a polyurethane foam board. The third heat insulation layer 4 is relatively thin, and when the external environment changes, it reduces the influence of the ambient temperature change above on the temperature measurement sensor; there are holes in the ceramic piece 31 on the second heat insulation layer 3 and the center of the third heat insulation layer 4.

[0059] Step S4: Place the designed thermal insulation structure and the temperature sensor 1 into the housing 5, coat a layer of sealant with high temperature resistance on the overall three thermal insulation layers and the gap with the housing 5 and cure it. Then, weld and fix the upper and lower bottom covers to the housing 5, and the tail end of the temperature sensor 1 extends out from the hole reserved on the upper bottom cover surface. There are two types of lower bottom covers: a common bottom cover and a calibration bottom cover 7. A semi-circular groove is provided on the upper wall of the calibration bottom cover 7, and a K-type thermocouple 71 is embedded in it. The thermocouple temperature measurement point 711 is located at the center point of the calibration bottom cover 7. Then, use the sealant with high temperature resistance to fill the groove until it is flat. The common bottom cover is similar to the upper bottom cover, and there is a hole in the center of the upper bottom cover. Among them, the sealant with high temperature resistance is a silicon-free high-temperature refractory sealant, and the materials of the housing 5 and the bottom cover are stainless steel 304, stainless steel 310 or ceramic. When coating the sealant with high temperature resistance, all operations are carried out in a vacuum chamber.

[0060] Step S5: Calibrate the temperature of the encapsulated temperature sensor 1. At this time, the lower bottom cover of the encapsulated temperature sensor 1 is replaced with the calibration bottom cover 7. Place the encapsulated sensor on a planar heat source, and collect a section of temperature change data of the target point and the measured point of the encapsulated sensor. The calibration data T sr of the measured point is the temperature data actually measured by the internal original contact temperature sensor 1, that is, the temperature data obtained by actually measuring the wavelength drift of the internal fiber Bragg grating and substituting it into the quadratic polynomial of the temperature sensitivity of this fiber Bragg grating. The measured point is located at the intersection of the interface between the upper and middle thermal protection materials and the central axis perpendicular to the bottom cover. T sr =ΔT FBG +T 0 ,T 0 is the initial temperature of the current environment; the calibration data T st of the target point is the temperature data measured by the K-type thermocouple 71 in the calibration bottom cover 7, that is, the temperature data of the heat source. The target point is located directly below the measured point, at the center of the bottom cover, and is measured by the thermocouple inside the lower calibration bottom cover 7 below. The encapsulated fiber Bragg grating is in close contact with the heat source. The heat of the heat source is transmitted from the target point along a coordinate axis direction to the measured point inside the encapsulated fiber Bragg grating 12, that is, one-dimensional heat transfer. Smooth the data of these two points to obtain the calibration data.

[0061] Step S6: Substitute the temperature calibration data T sr and T st into the heat balance equation, and its formula is:

[0062]

[0063] And use the least squares method to obtain the unknown parameters in this balance equation - the response lag time τ, the thermal resistance parameter ξ, and the reference temperature T ref , and obtain the unknown coefficient matrix of the heat balance equation as:

[0064] x = [τ, ξ + 1, ξ·Tref T =(B T B) -1 B T A

[0065] Step S7: Actual measurement; at this time, the bottom cover of the encapsulated temperature measurement sensor 1 is replaced with a common bottom cover, and the encapsulated temperature measurement sensor is placed in the environment to be measured; collect the actual measurement data T of the measured point vr , and substitute it into the formula:

[0066]

[0067] Where: k represents the measurement time.

[0068] Step S8: Output the actual measurement data T of the target point vt , that is, the temperature of the point to be measured; at the same time, when the environment to be measured changes, collect data, substitute it into the above formula, output the temperature to be measured, and perform error evaluation.

[0069] The present invention improves the upper limit of the temperature measured by the temperature measurement sensor by thermally insulating and encapsulating the fiber Bragg grating or thermocouple and other contact type temperature measurement sensors; and reduces the thermal hysteresis and thermal loss caused by the encapsulation structure by establishing a heat balance equation, pre-calibrating to obtain the unknown parameters of the equation, and correcting with the measured data, thereby improving the response speed and measurement accuracy of the sensor; at the same time, after the temperature measurement sensor is thermally insulated and encapsulated and corrected by the algorithm, the temperature measurement limit of the sensor itself is greatly improved, and it can work for a long time in an environment exceeding the temperature resistance upper limit of the sensor itself, while the response speed and accuracy of the temperature measurement sensor itself are not affected.

[0070] The encapsulation structure of the present invention can be used in an environment of 900 to 1800 °C. When the temperature of the heat source is transferred from the point to be measured to the internal sensor, the encapsulation structure of the present invention can isolate about 50% of the heat, so the sensor inside the encapsulation structure only needs to be able to withstand a temperature of 450 to 900 °C; and at the same time, after being corrected by the algorithm, it can work for a long time in an environment exceeding the temperature resistance upper limit of the sensor itself, and the response speed and accuracy of the temperature measurement sensor itself are not affected.

[0071] The above embodiments only represent several implementation manners of the present invention, and their descriptions are relatively specific and detailed, but they should not be construed as limiting the scope of the invention patent. It should be noted that for those of ordinary skill in the art, without departing from the concept of the present invention, several deformations and improvements can still be made, and these all belong to the protection scope of the present invention. Therefore, the protection scope of the invention patent should be subject to the appended claims.​

Claims

1. A packaging structure of an extended-range high-temperature sensor, characterized in that: include: A first heat insulation layer (2), a second heat insulation layer (3) and a third heat insulation layer (4) are arranged in sequence and sealed with high temperature resistant glue, wherein the interior of the second heat insulation layer (3) is provided with a groove for placing a temperature measuring sensor (1); The second heat-insulating layer (3) is a cylindrical structure formed by the aggregation of six columns with the same shape and a fan-shaped cross section; the six columns are divided into three groups, the three groups are respectively two second vacuum layers (32), two aerogels (33) and two ceramic heat-insulating tiles (34), and the six columns are arranged in a staggered manner, and the materials of the columns in the diagonal group are the same; The temperature sensor (1) is arranged in a sleeve (13) in a groove of the second thermal insulation layer (3), and a pigtail of the temperature sensor (1) extends from one end of the sleeve (13) and passes through the third thermal insulation layer (4).

2. The packaging structure of the extended-range high-temperature sensor according to claim 1, characterized in that: Ceramic sheets (31) are provided at both ends of the second heat insulation layer (3) for fixing the six sector-shaped columns; The first heat-insulating layer (2) comprises a first vacuum layer (21) and a high-temperature resistant layer (22) which are arranged in sequence, and the high-temperature resistant layer (22) is fixed to a ceramic sheet (31) on one side of the second heat-insulating layer (3); The high temperature resistant layer (22) is ceramic fiber, asbestos board or foam glass.

3. The packaging structure of the extended-range high-temperature sensor according to claim 1, characterized in that: The first heat insulation layer (2), the second heat insulation layer (3) and the third heat insulation layer (4) are sealed in the outer shell (5) by means of a sealing high temperature resistant adhesive, and a sealing high temperature resistant adhesive layer (6) is formed between the outer shell (5) and the first heat insulation layer (2), the second heat insulation layer (3) and the third heat insulation layer (4); A calibration bottom cover (7) is provided on the other side of the first thermal insulation layer (2), a semicircular groove is provided on the calibration bottom cover (7), and a K-type thermocouple (71) is embedded in the semicircular groove; a bottom cover (8) is provided on the other side of the third thermal insulation layer (4), and the pigtail of the temperature sensor (1) passes through the bottom cover (8) and extends; The housing (5), the calibration bottom cover (7) and the bottom cover (8) are fixed by welding.

4. The packaging structure of the extended-range high-temperature sensor according to claim 1, characterized in that: The two ends of the sleeve (13) are respectively fixed in the groove of the second heat insulation layer (3) by means of high temperature resistant glue (14), and the sleeve (13) is located at the intersection of six fan-shaped columns of the same shape; The high temperature resistant adhesive (14) is a specific high temperature resistant ceramic adhesive or a metal high temperature resistant adhesive.

5. The packaging structure of the extended-range high-temperature sensor according to claim 1, characterized in that: The temperature sensor (1) is an optical fiber or a thermocouple engraved with a fiber grating (12).

6. The packaging structure of the extended-range high-temperature sensor according to claim 3, characterized in that: The sealing high temperature resistant adhesive layer (6) is a silicon-free high temperature fire resistant sealant; The third heat insulation layer (4) is made of a polyurethane foam board with low thermal conductivity; The housing (5), the calibration bottom cover (7) and the bottom cover (8) are replaced with 304 stainless steel, 310 stainless steel or ceramic according to environmental requirements.

7. A signal correction method for an extended-range high-temperature sensor according to any one of claims 1 to 5, characterized in that: The following steps are involved: The temperature of the fiber Bragg grating (12) in the temperature sensor (1) is calibrated to establish the relationship between the temperature change of the fiber Bragg grating and the wavelength drift, which is expressed as: ΔT FBG =f(Δλ) Where: ΔT FBG represents the temperature change of the bare grating; Δλ represents the wavelength drift of the bare grating; Obtain the temperature change data of the target point and the actual measurement point of the extended-range high-temperature sensor, and the actual measurement point calibration data T sr is the temperature data measured by the temperature sensor (1), and the target point calibration data T st To calibrate the temperature data measured by the K-type thermocouple (71) in the bottom cover (7); The measured point calibration data T sr It is expressed as: T sr =ΔT FBG +T0 Where: T0 represents the initial temperature of the current environment; The measured point calibration data T sr Substitute the target point calibration data T into the heat balance equation st Calibrate and obtain the calibrated target point calibration data T st , and calibrate the data T according to the calibrated target point st Correct the actual measurement data.

8. The signal correction method of the extended-range high-temperature sensor according to claim 7, characterized in that: The correcting of the actual measurement data comprises: The measured point calibration data T sr Substitute into the heat balance equation to obtain the calibrated target point calibration data T st , the formula is: Use the least squares method to obtain the unknown parameters in the thermal balance equation: response hysteresis time τ, thermal resistance parameter ξ, reference temperature T ref , we obtain the unknown coefficient matrix of the heat balance equation, expressed as: X=[τ,ξ+1,ξ·T ref ] T =(B T B) -1 B T A The temperature-resistant sensor after temperature calibration is placed in the test environment, the fiber grating (12) is close to the test point, and the actual measurement data T of the actual measurement point is collected. vr , obtain the actual measurement data of the target point, that is, the temperature T of the point to be measured vt ; Its formula is: in: k represents the measurement time.

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