A method for improving temperature measurement accuracy of distributed optical fiber temperature measurement system

Abstract

The present invention relates to a method for improving the temperature measurement accuracy of a distributed optical fiber temperature measurement system. This method solves the problem of temperature measurement errors that are common in distributed optical fiber temperature measurement systems in the prior art. The method comprises: S1, arranging the distributed optical fiber temperature measurement in a ring-shaped mesh; S2, using an oil tank instead of a constant-temperature oil tank to wrap the distributed optical fiber temperature measurement; S3, arranging heat sinks around the oil tank to form a uniform temperature field, and placing a high-precision thermometer within the oil tank; S4, detecting and determining calibration coefficients at different time periods; and S5, adjusting the temperature information at each point along the distributed optical fiber temperature measurement system based on the calibration coefficients that vary at different time periods. The advantages of the present invention are: it effectively improves the temperature measurement accuracy of the distributed optical fiber temperature measurement system and provides excellent performance.

Description

Technical Field

[0001] The present invention relates to the technical field of optical fiber temperature measurement, and in particular to a method for improving the temperature measurement accuracy of a distributed optical fiber temperature measurement system. Background Art

[0002] Distributed fiber optic temperature measurement is a sensing technology that enables continuous temperature detection along an optical fiber. Based on the characteristic that the intensity of Raman scattering is solely temperature-dependent, it combines optical time-domain reflectometry (OTDR) technology to measure the temperature of an optical fiber over long distances with high precision. Currently, the most common method for calibrating distributed fiber optic temperature measurement systems is to obtain corresponding correction parameters by performing polynomial fitting between the demodulated temperature value and the actual value. These fitted parameters can only meet requirements within a certain temperature range. To improve the accuracy of the device, more parameters need to be introduced during high-frequency fitting. This makes the calibration of distributed fiber optic temperature measurement cumbersome and requires professional personnel. Furthermore, re-fitting is required when the external environment changes, making calibration very troublesome. Furthermore, due to the influence of temperature on optoelectronic devices, the gradual aging of optoelectronic devices over time, and the influence of factors such as constant temperature chamber temperature errors, measurement errors can occur, making it difficult to meet the long-term, high-precision measurement requirements of industrial environments.

[0003] To address the shortcomings of existing technologies, researchers have conducted extensive research and proposed various solutions. For example, a Chinese patent document discloses a distributed optical fiber temperature measurement system calibration method and apparatus [CN202110940136.0]. The method includes obtaining a first temperature detection value of a constant-temperature water bath and an ambient temperature detection value of the distributed optical fiber temperature measurement system using a temperature detector; obtaining a correction coefficient for the temperature detected by the distributed optical fiber temperature measurement system based on the first and ambient temperature detection values; obtaining a demodulated original temperature detection value of the distributed optical fiber temperature measurement system; and performing a correction calculation on the demodulated original temperature detection value of the distributed optical fiber temperature measurement system based on the correction coefficient to obtain a calibrated temperature detection value for the distributed optical fiber temperature measurement system.

[0004] The above solution solves the problem of cumbersome calibration method of distributed optical fiber temperature measurement in the existing technology to a certain extent, but the solution still has many shortcomings. For example, temperature detection is affected by the external environment and the optoelectronic device of its own temperature measurement, which is prone to errors and affects the accuracy of temperature measurement. Summary of the Invention

[0005] The object of the present invention is to provide a method for improving the temperature measurement accuracy of a distributed optical fiber temperature measurement system in order to solve the above problems.

[0006] To achieve the above object, the present invention adopts the following technical solution: a method for improving the temperature measurement accuracy of a distributed optical fiber temperature measurement system, characterized in that the method comprises the following steps:

[0007] S1, using a ring mesh to arrange distributed temperature measurement optical fibers;

[0008] S2. Use oil tank instead of constant temperature oil tank to wrap distributed temperature measurement optical fiber;

[0009] S3. Arrange heat sinks around the oil tank to form a uniform temperature field, and place a high-precision thermometer in the oil tank;

[0010] S4. Detect and determine the calibration coefficients at different time periods;

[0011] S5. Adjust the temperature information of each point along the distributed temperature measurement optical fiber according to the calibration coefficients that change in different time periods.

[0012] An ordinary oil tank is used to replace the constant temperature oil tank, and heat sinks are set around the oil tank to form a uniform temperature field. A high-precision thermometer is used to detect the temperature of the oil tank and the distributed temperature measurement optical fiber. At the same time, calibration coefficients are set for different time periods. The actual detection temperature is obtained by using the temperature within the set time period and the calibration coefficient within the time period, thereby improving the temperature detection accuracy of the distributed temperature measurement optical fiber.

[0013] In the above-mentioned method for improving the temperature measurement accuracy of a distributed optical fiber temperature measurement system, step S1 is specifically divided into the following steps:

[0014] S11, dividing the temperature measurement area to form a temperature measurement grid;

[0015] S12, detecting the average temperature in each temperature measurement grid;

[0016] S13, finding the point in the temperature measurement grid that is closest to the mean temperature as the temperature measurement node in the temperature measurement grid;

[0017] S14. Connect the temperature measurement nodes in each temperature measurement grid through distributed temperature measurement optical fibers to form a temperature measurement ring network.

[0018] By dividing the temperature measurement area and using the point in the temperature measurement area closest to the temperature mean as the temperature measurement node, the accuracy of temperature detection can be effectively improved and the impact of the external environment on the detection results can be reduced.

[0019] In the above-mentioned method for improving the temperature measurement progress of a distributed optical fiber temperature measurement system, detection methods of different time periods are adopted when detecting the temperature mean within the temperature measurement grid, and the temperature mean values ​​measured in different time periods are used to find points within the temperature measurement area that are close to the temperature mean as temperature measurement nodes. All temperature measurement nodes within the temperature measurement area are connected in parallel to the passing distributed temperature measurement optical fiber through a temperature measurement optical fiber branch line, and a timed opening and closing switch is set on the temperature measurement optical fiber branch line. The distributed temperature measurement optical fiber is connected to a WDM splitter, an APD amplifier and a high-speed data acquisition card in sequence, and the high-speed data acquisition card is connected to a control module, and the control module is connected to each timed opening and closing switch.

[0020] The temperature measurement node closest to the average temperature in the current temperature measurement area is opened in a time-division manner, thereby improving the accuracy of photoelectric signal modulation.

[0021] In the above-mentioned method for improving the temperature measurement progress of a distributed optical fiber temperature measurement system, in step S3, the cross-section of the oil tank is rectangular or circular, the heat sink is tightly fitted to the circumferential outer wall of the oil tank, and the high-precision thermometer is arranged on one side of the distributed temperature measurement optical fiber and fits together with the distributed temperature measurement optical fiber. The resistance value of the high-precision thermometer is proportional to the temperature, that is, the resistance value of the high-precision thermometer increases linearly with increasing temperature.

[0022] The high-precision thermometer can accurately read the real-time temperature in the optical fiber and oil tank, and make real-time adjustments to make the adjusted temperature more accurate.

[0023] In the above-mentioned method for improving the temperature measurement performance of the distributed optical fiber temperature measurement system, in step S4, the calibration coefficient determination specifically includes the following steps:

[0024] S41, input the detection temperature, and preset the signal acquisition start section and signal acquisition end section;

[0025] S42, collecting the intensities of the anti-Stokes signal and the Stokes signal backscattered by the distributed temperature measurement optical fiber at the signal collection starting end;

[0026] S43, collecting the intensities of the anti-Stokes signal and the Stokes signal backscattered by the distributed temperature measurement optical fiber at the signal acquisition end;

[0027] S44, calculating a ratio of the anti-Stokes signal and the Stokes signal collected at the signal collection start end and the anti-Stokes signal and the Stokes signal collected at the signal collection end end, and drawing a ratio change curve within a set time end;

[0028] S45. Obtain the calibration coefficients in each time period according to the ratio change curve.

[0029] The calibration coefficients of different time periods are measured, and the corresponding calibration coefficients are used in different temperature measurement time periods to improve the accuracy of converting photoelectric signals into temperature signals.

[0030] In the aforementioned method for improving the temperature measurement performance of a distributed fiber-optic temperature measurement system, in step S5, a high-precision thermometer is used to read the real-time temperature of the oil tank and the temperature of the distributed temperature measurement fiber during the current time period. The actual measured temperature value is adjusted using the calibration coefficient for the current time period. The adjusted temperature value is then transmitted to a computer and displayed on a display screen. This real-time adjustment method facilitates timely monitoring of temperature changes and facilitates timely adjustments during daily operations.

[0031] In the aforementioned method for improving the temperature measurement performance of a distributed fiber-optic temperature measurement system, a recording time period and a time recording node within that time period are set. When a set time recording node is reached, the computer records the mediated temperature value at the current time node into a database. A temperature change curve is then plotted based on the temperature values ​​recorded over several recording time periods to obtain the average temperature within the fixed time period. This average temperature can then be compared with the measured temperature to determine whether the temperature within the measurement area is abnormal.

[0032] In the above-mentioned method for improving the temperature measurement progress of a distributed optical fiber temperature measurement system, the average temperature value within a fixed time period is compared with the actual temperature value measured within the time period, and a difference range is set. If the actual temperature value measured exceeds the preset difference range, the measured temperature is determined to be invalid and an alarm is sent to the computer. If the actual temperature value measured is within the preset difference range, the current measured temperature is determined to be valid and is displayed normally on the display screen.

[0033] This setting can improve the safety of optical fiber temperature measurement and promptly understand whether the temperature in the area where the temperature measurement junction is located exceeds the warning value.

[0034] In the above-mentioned method for improving the temperature measurement progress of a distributed optical fiber temperature measurement system, when the distributed temperature measurement optical fiber measures the temperature of a certain temperature measurement grid, according to different time periods, the control module is used to open the timed opening and closing switch of the temperature measurement optical fiber branch line on the temperature measurement node closest to the temperature average value within the time period, and close other timed opening and closing switches.

[0035] In each temperature measurement grid, only one temperature measurement optical fiber branch line closest to the temperature average of the temperature measurement grid in the current time period is open in the same time period, which is beneficial to reducing external environmental interference.

[0036] In the aforementioned method for improving the temperature measurement performance of a distributed fiber-optic temperature measurement system, positioning fibers are installed within the temperature measurement fiber spurs, timed on / off switches, and distributed temperature measurement fibers. A positioning diagram of the positioning fibers is synchronized to a temperature monitoring platform. The temperature monitoring platform is connected to a monitoring screen to display the location of the temperature measurement nodes and the measured real-time temperature in real time. The positioning fibers can locate the temperature measurement nodes, and the positioning diagram is synchronized to the temperature monitoring platform, facilitating remote, real-time observation and providing excellent flexibility.

[0037] Compared with the existing technology, the advantages of the present invention are: a constant temperature oil tank is replaced by an ordinary oil tank, and a heat sink is arranged around the oil tank, and a high-precision thermometer is arranged at the distributed temperature measurement optical fiber in the oil tank, thereby forming a uniform temperature field. At the same time, the temperature measurement area is divided, temperature measurement nodes are set, and calibration coefficients in different time periods are detected. Corresponding temperature measurement nodes and calibration coefficients are used when measuring temperature in different time periods, thereby improving the temperature measurement accuracy of the distributed temperature measurement optical fiber. BRIEF DESCRIPTION OF THE DRAWINGS

[0038] Figure 1 It is a schematic diagram of the temperature measurement grid structure in the present invention;

[0039] Figure 2 This is the distributed temperature measurement optical fiber distribution diagram of the present invention;

[0040] Figure 3 This is a structural diagram of the present invention when the temperature measurement nodes in the same temperature measurement area are connected to the distributed temperature measurement optical fiber;

[0041] Figure 4 It is a cross-sectional view of the oil tank of the present invention when it is rectangular;

[0042] Figure 5 is a cross-sectional view of the oil groove in the present invention when it is annular;

[0043] Figure 6 It is a local structural connection block diagram of the present invention;

[0044] In the figure: distributed temperature measurement optical fiber 1, temperature measurement area 11, temperature measurement grid 12, temperature measurement node 13, temperature measurement optical fiber branch 14, timed opening and closing switch 15, control module 16, oil tank 2, heat sink 21, high-precision thermometer 3, positioning optical fiber 4, temperature detection platform 41, detection screen 42. DETAILED DESCRIPTION

[0045] The present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0046] like Figure 1-6 As shown, a method for improving the temperature measurement accuracy of a distributed optical fiber temperature measurement system includes the following steps:

[0047] S1, using a ring mesh to arrange distributed temperature measurement optical fiber 1;

[0048] S2, using oil tank 2 instead of constant temperature oil tank to wrap distributed temperature measurement optical fiber 1;

[0049] S3. Arrange heat sinks 21 circumferentially around the oil tank 2 to form a uniform temperature field, and place a high-precision thermometer 3 in the oil tank 2;

[0050] S4. Detect and determine the calibration coefficients at different time periods;

[0051] S5. Calculate the temperature information of each point along the distributed temperature measurement optical fiber 1 according to the calibration coefficients that change in different time periods.

[0052] Since the temperature of a constant temperature oil tank is prone to errors after long-term use, an ordinary oil tank 2 is used to replace the constant temperature oil tank, and a heat sink 21 is arranged circumferentially around the oil tank 2 to form a uniform temperature field. A high-precision thermometer 3 that fits tightly with the distributed temperature measurement optical fiber 1 is arranged in the oil tank 2 to perform temperature detection, and the temperature changes in the temperature oil tank are detected in real time. At the same time, the calibration coefficient in different time periods is measured, and the actual temperature measured by the current distributed temperature measurement optical fiber 1 is obtained by combining the measured temperature of the distributed temperature measurement optical fiber 1 in different time periods with the corresponding calibration coefficient.

[0053] Among them, step S1 is specifically divided into the following steps:

[0054] S11, dividing the temperature measurement area 11 to form a temperature measurement grid 12;

[0055] S12, detecting the average temperature in each temperature measurement grid 12;

[0056] S13, finding the point in the temperature measurement grid 12 that is closest to the mean temperature as the temperature measurement node 13 in the temperature measurement grid 12;

[0057] S14, connecting the temperature measurement nodes 13 in each temperature measurement grid 12 through the distributed temperature measurement optical fiber 1 to form a temperature measurement ring network.

[0058] The area that needs to pass through the side of the distributed temperature measurement optical fiber 1 is divided into a temperature measurement area 11 and the temperature average values ​​of different time periods in the temperature measurement area 11 are detected. At the same time, according to the temperature average difference in different time periods, the point closest to the temperature average value in the temperature measurement area 11 is found as the temperature measurement node of the time period, which is used to be enabled in different time periods to reduce the impact of the external environment on temperature measurement.

[0059] Furthermore, when detecting the temperature average value in the temperature measurement grid 12, detection methods of different time periods are adopted, and the temperature average values ​​measured in different time periods are used to find points in the temperature measurement area 11 that are close to the temperature average value as temperature measurement nodes 13. All temperature measurement nodes 13 in the temperature measurement area 11 are connected in parallel to the distributed temperature measurement optical fiber 1 passing through the temperature measurement optical fiber branch 14, and a timed opening and closing switch 15 is set on the temperature measurement optical fiber branch 14. The distributed temperature measurement optical fiber 1 is connected to a WDM splitter, an APD amplifier and a high-speed data acquisition card in sequence, and the high-speed data acquisition card is connected to a control module 16, and the control module 16 is connected to each timed opening and closing switch 15.

[0060] The WDM optical splitter, APD amplifier and high-speed data acquisition card are used to collect the photoelectric signal of the distributed temperature measurement optical fiber 1, and the timing opening and closing switch 15 is used to determine the activation of the corresponding temperature measurement optical fiber branch line 14 in different time periods.

[0061] In detail, in step S3, the cross-section of the oil tank 2 is rectangular or circular, the heat sink 21 is tightly fitted to the circumferential outer wall of the oil tank 2, and the high-precision thermometer 3 is arranged on one side of the distributed temperature measuring optical fiber 1 and fits together with the distributed temperature measuring optical fiber 1. The resistance of the high-precision thermometer 3 is proportional to the temperature, that is, the resistance of the high-precision thermometer 3 increases linearly with increasing temperature.

[0062] The high-precision thermometer 3 has the characteristics of anti-interference and anti-vibration, stable performance, high accuracy and long service life, and is mainly used to detect the temperature in the oil tank 2 and the temperature value of the distributed temperature measurement optical fiber 1.

[0063] In step S4, the calibration coefficient determination specifically includes the following steps:

[0064] S41, input the detection temperature, and preset the signal acquisition start section and signal acquisition end section;

[0065] S42, collecting the intensities of the anti-Stokes signal and the Stokes signal backscattered by the distributed temperature measurement optical fiber 1 at the signal collection starting end;

[0066] S43, collecting the intensities of the anti-Stokes signal and the Stokes signal backscattered by the distributed temperature measurement optical fiber 1 at the signal collection end;

[0067] S44, calculating a ratio of the anti-Stokes signal and the Stokes signal collected at the signal collection start end and the anti-Stokes signal and the Stokes signal collected at the signal collection end end, and drawing a ratio change curve within a set time end;

[0068] S45. Obtain the calibration coefficients in each time period according to the ratio change curve.

[0069] This is mainly used to determine the calibration coefficients in different time periods, to adjust the measured temperature in different time periods, and to adjust according to actual conditions to improve the accuracy and flexibility of temperature measurement.

[0070] In step S5, a high-precision thermometer 3 is used to read the real-time temperature in the oil tank 2 and the temperature of the distributed temperature measurement optical fiber 1 in the current time period, and the calibration coefficient in the current time period is used to adjust the actual detected temperature value, and the adjusted temperature value is transmitted to the computer and displayed on the display screen.

[0071] Specifically, a recording time period and a time recording node within the time period are set. When the set time recording node is reached, the computer records the mediated temperature value of the current time node into the database, and draws a temperature value change curve based on the temperature values ​​recorded in several recording time periods to obtain the average temperature within a fixed time period.

[0072] The average temperature value obtained within a fixed time period is the standard value within that time period. The actual adjustment temperature is compared with the historical standard value to determine the effective measurement temperature.

[0073] Preferably, the temperature average value within a fixed time period is compared with the actual temperature value measured within the time period, and a difference range is set. If the measured actual temperature value exceeds the preset difference range, the measured temperature is determined to be invalid and an alarm is issued to the computer. If the measured actual temperature value is within the preset difference range, the current measured temperature is determined to be valid and is displayed normally on the display screen.

[0074] The difference range here is the difference range between the maximum and minimum temperature values ​​mediated during the time period and the average temperature value.

[0075] Furthermore, when the distributed temperature measurement optical fiber 1 measures the temperature of a certain temperature measurement grid 12, the control module 16 is used to open the timed opening and closing switch 15 of the temperature measurement optical fiber branch line 14 on the temperature measurement node 13 closest to the temperature average value within the time period, and close other timed opening and closing switches 15 according to different time periods.

[0076] More specifically, a positioning optical fiber 4 is provided in the temperature measurement optical fiber branch line 14, the timed opening and closing switch 15 and the distributed temperature measurement optical fiber 1, and the positioning circuit diagram of the positioning optical fiber 4 is synchronized to the temperature detection platform 41. The temperature monitoring platform 41 is connected to the detection screen 42 to display the position of the temperature measurement node 13 and the measured real-time temperature in real time.

[0077] To sum up, the principle of this embodiment is: using an ordinary oil tank 2 to replace the constant temperature oil tank, and dividing the area where the distributed temperature measurement optical fiber 1 is to perform temperature measurement into a temperature measurement area 11, and setting a temperature measurement node 13 in the temperature measurement area 11, the temperature measurement node 13 is connected to the distributed temperature measurement optical fiber 1 through a temperature measurement optical fiber branch line 14, and a timed opening and closing switch 15 is set on the temperature measurement optical fiber branch line 14, and the temperature measurement node 13 closest to the temperature average value of the current time period of the temperature measurement area 11 in the time period is turned on in different temperature measurement time periods. At the same time, the calibration coefficients in different time periods are detected, and the actual measured temperature is adjusted using the calibration coefficients in different time periods and the measured temperature. At the same time, the temperature average value of the adjusted temperature in the time period is set, and the preset temperature difference range is compared with the adjusted actual measured temperature to retain the effective measured temperature.

[0078] The specific embodiments described herein are merely illustrative of the spirit of the present invention. Persons skilled in the art may make various modifications, additions, or substitutions to the described specific embodiments without departing from the spirit of the present invention or exceeding the scope of the appended claims.

[0079] Although this document frequently uses terms such as distributed temperature measurement optical fiber 1, temperature measurement area 11, temperature measurement grid 12, temperature measurement node 13, temperature measurement optical fiber branch line 14, timed on / off switch 15, control module 16, oil tank 2, heat sink 21, high-precision thermometer 3, positioning optical fiber 4, temperature detection platform 41, and detection screen 42, the use of other terms is not excluded. These terms are used solely to more conveniently describe and explain the essence of the present invention; interpreting them as any additional limitations would be contrary to the spirit of the present invention.

Claims

1. A method for improving the temperature measurement accuracy of a distributed optical fiber temperature measurement system, characterized in that: This method comprises the following steps: S1, using a ring mesh to arrange distributed temperature measurement optical fibers (1); S2, using the oil tank (2) instead of the constant temperature oil tank to wrap the distributed temperature measurement optical fiber (1); S3. Arrange heat sinks (21) circumferentially around the oil tank (2) to form a uniform temperature field, and place a high-precision thermometer (3) in the oil tank (2); S4. Detect and determine the calibration coefficients at different time periods; S5, adjusting the temperature information of each point along the distributed temperature measurement optical fiber (1) according to the calibration coefficients that change in different time periods; Step S1 is specifically divided into the following steps: S11, dividing the temperature measurement area (11) to form a temperature measurement grid (12); S12, detecting the average temperature in each temperature measurement grid (12); S13, finding a point in the temperature measurement grid (12) that is closest to the temperature mean as a temperature measurement node (13) in the temperature measurement grid (12); S14, connecting the temperature measurement nodes (13) in each temperature measurement grid (12) through the distributed temperature measurement optical fiber (1) to form a temperature measurement ring network; When detecting the temperature mean value in the temperature measurement grid (12), detection methods of different time periods are adopted, and the temperature mean values ​​measured in different time periods are used to find points in the temperature measurement area (11) that are close to the temperature mean value as temperature measurement nodes (13), and all temperature measurement nodes (13) in the temperature measurement area (11) are connected in parallel to the distributed temperature measurement optical fiber (1) passing through the temperature measurement optical fiber branch (14), and a timed opening and closing switch (15) is set on the temperature measurement optical fiber branch (14), and the distributed temperature measurement optical fiber (1) is connected to a WDM splitter, an APD amplifier and a high-speed data acquisition card in sequence, and the high-speed data acquisition card is connected to a control module (16), and the control module (16) is connected to each timed opening and closing switch (15); When the distributed temperature measurement optical fiber (1) measures the temperature of a certain temperature measurement grid (12), the control module (16) is used to open the timed opening and closing switch (15) of the temperature measurement optical fiber branch line (14) on the temperature measurement node (13) closest to the temperature average value within the time period according to different time periods, and close the other timed opening and closing switches (15).

2. A method for improving the temperature measurement progress of a distributed optical fiber temperature measurement system according to claim 1, characterized in that: In step S3, the cross-section of the oil tank (2) is rectangular or circular, the heat sink (21) is tightly fitted on the circumferential outer wall of the oil tank (2), and the high-precision thermometer (3) is arranged on one side of the distributed temperature measurement optical fiber (1) and is fitted with the distributed temperature measurement optical fiber (1), and the resistance of the high-precision thermometer (3) is proportional to the temperature, that is, the resistance of the high-precision thermometer (3) increases linearly with increasing temperature.

3. The method for improving the temperature measurement progress of a distributed optical fiber temperature measurement system according to claim 1, characterized in that: In step S4, the calibration coefficient determination specifically includes the following steps: S41, input the detection temperature, and preset the signal acquisition start section and signal acquisition end section; S42, collecting the intensity of the anti-Stokes signal and the Stokes signal backscattered by the distributed temperature measurement optical fiber (1) at the signal collection starting end; S43, collecting the intensity of the anti-Stokes signal and the Stokes signal backscattered by the distributed temperature measurement optical fiber (1) at the signal collection end; S44, calculating a ratio of the anti-Stokes signal and the Stokes signal collected at the signal collection start end and the anti-Stokes signal and the Stokes signal collected at the signal collection end end, and drawing a ratio change curve within a set time end; S45. Obtain the calibration coefficients in each time period according to the ratio change curve.

4. A method for improving the temperature measurement progress of a distributed optical fiber temperature measurement system according to claim 3, characterized in that: In step S5, a high-precision thermometer (3) is used to read the real-time temperature in the oil tank (2) and the temperature of the distributed temperature measurement optical fiber (1) in the current time period, and the actual detected temperature value is adjusted using the calibration coefficient in the current time period. The adjusted temperature value is transmitted to the computer and displayed on the display screen.

5. A method for improving the temperature measurement progress of a distributed optical fiber temperature measurement system according to claim 4, characterized in that: Set the recording time period and the time recording node within the time period. When the set time recording node is reached, the computer will record the mediated temperature value of the current time node into the database, and draw a temperature value change curve based on the temperature values ​​recorded in several recording time periods to obtain the average temperature within a fixed time period.

6. A method for improving the temperature measurement progress of a distributed optical fiber temperature measurement system according to claim 5, characterized in that: The average temperature value within a fixed time period is compared with the actual temperature value measured within the time period, and a difference range is set. If the actual temperature value measured exceeds the preset difference range, the measured temperature is determined to be invalid and an alarm is issued to the computer. If the actual temperature value measured is within the preset difference range, the current measured temperature is determined to be valid and is displayed normally on the display screen.

7. The method for improving the temperature measurement progress of a distributed optical fiber temperature measurement system according to claim 1, characterized in that: The temperature measuring optical fiber branch line (14), the timed opening and closing switch (15) and the distributed temperature measuring optical fiber (1) are provided with a positioning optical fiber (4), and the positioning circuit diagram of the positioning optical fiber (4) is synchronized to the temperature detection platform (41). The temperature detection platform (41) is connected to the detection screen (42) to display the position of the temperature measuring node (13) and the measured real-time temperature in real time.

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