System and method for static and dynamic calibration of thin film thermocouples

Abstract

The present invention discloses a system and method for static and dynamic calibration of a thin-film thermocouple, and relates to the technical field of parameter calibration of temperature sensor devices. The system comprises a temperature control box module, a thermocouple module, a pulsed laser source module, a photodetector, and a zero-degree thermostat. The temperature control box module comprises a sealed box with a light-transmitting window and a temperature control unit, and the temperature control unit is used to control the temperature inside the sealed box. The thermocouple module comprises a thin-film thermocouple to be calibrated and a standard thin-film thermocouple located inside the sealed box, a first cold end and a first output end connected to the thin-film thermocouple to be calibrated and extending to the outside of the sealed box, and a second cold end and a second output end connected to the standard thin-film thermocouple and extending to the outside of the sealed box. The first cold end and the second cold end are placed in the zero-degree thermostat. The pulsed laser source module is used to generate a pulsed laser, and to make the pulsed laser illuminate the thin-film thermocouple to be calibrated and the photodetector simultaneously through the light-transmitting window.

Description

Technical Field

[0001] The present invention relates to the technical field of temperature sensor device parameter calibration, and in particular to a system and method for static and dynamic calibration of thin film thermocouples. Background Art

[0002] As the core of the aviation field, it is crucial to ensure the stable performance of aircraft engines during operation, and temperature detection is an important means to ensure the stable performance of engines during operation. When an aircraft flies in the atmosphere, the temperature of the outer surface material of its casing will rise rapidly. Accurately detecting the temperature of the outer surface of the casing is of great significance to the rationality of the design of the aircraft's thermal protection system. The instantaneous detection of the barrel temperature during rocket launch and the detection of the inner wall temperature of the internal combustion engine barrel, etc., all require temperature sensors with high temperature resistance, stable static characteristics, small size, no damage to the structure to be tested, and no impact on the test environment.

[0003] With the development of MEMS (Microelectro Mechanical Systems) technology, thin-film thermocouples are considered ideal temperature sensing devices that combine these characteristics. They offer advantages such as non-destructiveness to the structure being tested, minimal impact on the test environment, excellent linearity, high sensitivity, high-temperature resistance, flexible spatial positioning, negligible heat capacity, and extremely fast response speeds (typically measured in microseconds or even nanoseconds).

[0004] Static calibration and dynamic calibration are key steps to ensure that the developed thin-film thermocouples can meet industrial applications. Static calibration refers to placing the thin-film thermocouple to be calibrated and the standard thin-film thermocouple in the same temperature test environment, recording the output potentials of the two thin-film thermocouples at multiple moments and corresponding to these moments during the temperature rise process, and fitting the temperature-output potential relationship curve of the thin-film thermocouple to be calibrated through the temperature-output potential relationship curve of the standard thin-film thermocouple. Dynamic calibration refers to inputting a large amount of energy into the thin-film thermocouple to be calibrated in a short period of time to cause it to heat up rapidly, and measuring its transient response time. The transient response time is divided into two parts: the pre-response time and the post-response time. Among them, the pre-response time refers to the time period from the start of the thin-film thermocouple to be calibrated to receive energy input until the potential output begins, and the post-response time refers to the time period from the start of the potential output to the peak value of the potential output as the thin-film thermocouple gradually increases in temperature according to the amount of input energy.

[0005] The existing static calibration and dynamic calibration require the construction of separate calibration platforms. The thin-film thermocouple to be calibrated needs to be transferred between the two platforms, which can easily damage the thin-film thermocouple to be calibrated. In addition, the calibration structure is complex, the operation is inconvenient, and errors are easily introduced. Summary of the Invention

[0006] The present invention provides a system and method for static and dynamic calibration of thin film thermocouples, which can simplify the calibration structure, thereby simplifying the operation, reducing the error introduced during the operation, and preventing the thin film thermocouple to be calibrated from being damaged due to transfer.

[0007] The present invention provides a system for static and dynamic calibration of thin-film thermocouples, comprising a temperature control box module, a thermocouple module, a pulsed laser source module, a photodetector, and a zero-degree thermostat; the temperature control box module comprises a sealed box with a light-transmitting window and a temperature control unit, the temperature control unit being used to control the temperature inside the sealed box; the thermocouple module comprises a thin-film thermocouple to be calibrated and a standard thin-film thermocouple located inside the sealed box, a first cold end and a first output end connected to the thin-film thermocouple to be calibrated and extending to the outside of the sealed box, and a second cold end and a second output end connected to the standard thin-film thermocouple and extending to the outside of the sealed box; the first cold end and the second cold end are placed in the zero-degree thermostat; the pulsed laser source module is used to generate a pulsed laser, and to allow the pulsed laser to illuminate the thin-film thermocouple to be calibrated and the photodetector simultaneously through the light-transmitting window.

[0008] Furthermore, the system further includes a data collector connected to the first output end, the second output end and the third output end of the photodetector.

[0009] Optionally, the temperature control unit includes a first control device, a water cooling device and a heating device connected to the first control device; the water cooling device is partially embedded in the wall of the closed box; and the heating device is arranged inside the closed box.

[0010] Furthermore, the thin film thermocouple to be calibrated and the standard thin film thermocouple are symmetrically arranged on both sides of the heating device.

[0011] Optionally, the heating device is a graphite heater.

[0012] Furthermore, the above system also includes a vacuum pump connected to the first control device and the closed box, which is used to enable the first control device to vacuum the inside of the closed box.

[0013] Optionally, the pulse laser source module includes a spectrometer, a second control device and a pulse laser connected to each other; the second control device is used to control the pulse laser to generate the pulse laser; the spectrometer is used to divide the pulse laser into two equal parts, respectively irradiating the thin film thermocouple to be calibrated and the photodetector.

[0014] The present invention provides a method for static and dynamic calibration of a thin film thermocouple, comprising: (1) adjusting the internal temperature of a sealed box body by using a temperature regulating box module, and measuring the output potentials of the first output terminal and the second output terminal of the thermocouple module, so that the thin film thermocouple to be calibrated in the thermocouple module is statically calibrated according to the corresponding relationship between the temperature and the output potential of a standard thin film thermocouple; (2) simultaneously irradiating the thin film thermocouple to be calibrated and a photodetector with a pulse laser generated by a pulse laser source module, and measuring the output potentials of the first output terminal and the third output terminal of the photodetector, so that the photodetector is statically calibrated according to the corresponding relationship between the temperature and the output potential of the thin film thermocouple to be calibrated; (3) simultaneously irradiating the thin film thermocouple to be calibrated and the photodetector with a pulse laser generated by the pulse laser source module, and measuring the output potentials of the first output terminal and the third output terminal of the photodetector, so that the thin film thermocouple to be calibrated is dynamically calibrated according to the corresponding relationship between the temperature and the output potential of the photodetector.

[0015] Furthermore, between step (1) and step (2), the method further includes preheating the pulse laser source module and adjusting the power and pulse frequency of the pulse laser.

[0016] Optionally, in step (3), the sampling frequency for measuring the output potential of the first output terminal and the third output terminal of the photodetector is 5 to 10 times the pulse frequency of the pulse laser.

[0017] In the system and method for static and dynamic calibration of thin-film thermocouples provided in an embodiment of the present invention, the temperature control unit of the temperature control box module can adjust the temperature inside the closed box, so that the thin-film thermocouple to be calibrated and the standard thin-film thermocouple located inside the closed box generate an output potential at the output end when the temperature changes. By measuring the output potential and based on the temperature-output potential correspondence of the standard thin-film thermocouple, static calibration of the thin-film thermocouple to be calibrated can be achieved.

[0018] In addition, the pulse laser generated by the pulse laser source module can illuminate the thin film thermocouple to be calibrated through the light-transmitting window on the sealed box, and at the same time, the pulse laser illuminates the photodetector located outside the sealed box, so that the thin film thermocouple to be calibrated and the photodetector are heated at the same time, and the output potential of the thin film thermocouple to be calibrated and the output potential of the photodetector are measured. According to the temperature-output potential correspondence of the statically calibrated thin film thermocouple to be calibrated, the static calibration of the photodetector can be achieved.

[0019] Finally, the pulse laser generated by the pulse laser source module is used to simultaneously heat the thin film thermocouple to be calibrated and the photodetector that has been statically calibrated. The output potential of the thin film thermocouple to be calibrated and the output potential of the photodetector are measured. According to the temperature-output potential correspondence of the statically calibrated photodetector, dynamic calibration of the thin film thermocouple to be calibrated can be achieved.

[0020] Therefore, the above-mentioned system and method realize the integration of static calibration and dynamic calibration of the thin film thermocouple to be calibrated, and can complete the static and dynamic calibration of the thin film thermocouple to be calibrated on one platform. There is no need to transfer the thin film thermocouple to be calibrated between different platforms, which can prevent the thin film thermocouple to be calibrated from being damaged due to transfer; the structure is simple, the operation is convenient, and the error introduced during the operation is reduced. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following is a brief introduction to the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative labor.

[0022] Figure 1 A structural block diagram of a system for static and dynamic calibration of thin-film thermocouples provided by an embodiment of the present invention;

[0023] Figure 2 A flow chart of a method for static and dynamic calibration of a thin film thermocouple provided by an embodiment of the present invention;

[0024] Figure 3 for Figure 2 Schematic diagram of the method for dynamic calibration of thin film thermocouples in the provided method. DETAILED DESCRIPTION

[0025] To make the objectives, technical solutions, and advantages of the present invention more clear, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts shall fall within the scope of protection of the present invention.

[0026] To make the technical solution of the present invention clearer, embodiments of the present invention are described in detail below with reference to the accompanying drawings.

[0027] The embodiment of the present invention provides a system for static and dynamic calibration of thin film thermocouples, such as Figure 1As shown, the system includes a temperature control box module 11 , a thermocouple module 12 , a pulse laser source module 13 , a photodetector 14 , and a zero-degree thermostat 15 .

[0028] The temperature control box module 11 includes a sealed box body 111 having a light-transmitting window A and a temperature control unit 112 . The temperature control unit 112 is used to control the temperature inside the sealed box body 111 .

[0029] The above-mentioned thermocouple module 12 includes a thin film thermocouple 121 to be calibrated and a standard thin film thermocouple 122 located inside the sealed box 111, a first cold end 123 and a first output end 124 connected to the thin film thermocouple 121 to be calibrated and extending to the outside of the sealed box 111, and a second cold end 125 and a second output end 126 connected to the standard thin film thermocouple 122 and extending to the outside of the sealed box 111; the first cold end 123 and the second cold end 125 are placed in the zero-degree thermostat 15.

[0030] The pulse laser source module 13 is used to generate a pulse laser B, and the pulse laser B is used to illuminate the thin film thermocouple 122 to be calibrated through the light-transmitting window A and the photodetector 14 at the same time.

[0031] The basic principle of thin-film thermocouple temperature measurement is the thermoelectric effect (or temperature difference effect). Two dissimilar metal thin films are connected end-to-end to form a closed loop. Unequal temperatures at the two junctions generate an output potential within the loop. During use, one junction is typically maintained at a constant temperature (e.g., 0°C) as the cold junction, while the other junction, the hot junction, is placed at the temperature measurement location. As the hot junction temperature changes, the output potential within the loop also changes. Each thin-film thermocouple has a fixed relationship between temperature and output potential. By measuring the output potential within the loop, the measured temperature can be determined based on this relationship.

[0032] Newly manufactured thin-film thermocouples need to use a static calibration method to obtain the above-mentioned correspondence between temperature and output potential. The commonly used static calibration method is the comparison method, that is, using the thin-film thermocouple to be calibrated and a standard thin-film thermocouple with standard components to measure the same temperature, changing the temperature within a certain range, recording the output potential of multiple sampling points of the two thin-film thermocouples, and obtaining a set of output potential data. According to the correspondence between the known temperature and output potential of the standard thin-film thermocouple, the temperature value of each sampling point can be obtained, thereby obtaining the temperature and corresponding output potential of the thin-film thermocouple to be calibrated at each sampling point. These sampling points are then plotted in the temperature-output potential diagram, and the correspondence between the temperature and output potential of the thin-film thermocouple to be calibrated is finally obtained through fitting, thereby completing the static calibration of the thin-film thermocouple to be calibrated.

[0033] In the system for static and dynamic calibration of thin-film thermocouples provided in the above embodiment, a comparison method is used to perform static calibration on the thin-film thermocouple to be calibrated 121. Specifically, the thin-film thermocouple to be calibrated 121 and the standard thin-film thermocouple 122 are placed inside the sealed box 111 (here, for the sake of clarity, the hot ends of the two thin-film thermocouples located inside the sealed box are referred to as the thin-film thermocouple to be calibrated 121 and the standard thin-film thermocouple 122), and the first cold end 123 extending from the thin-film thermocouple to be calibrated 121 to the outside of the sealed box 111 and the second cold end 125 extending from the standard thin-film thermocouple 122 to the outside of the sealed box 111 are placed in a zero-degree thermostat 15 to ensure that the temperature of the cold ends is constant at 0°C.

[0034] A first output terminal 124 extending from the thin film thermocouple to be calibrated to the outside of the sealed box 111 and a second output terminal 126 extending from the standard thin film thermocouple 122 to the outside of the sealed box 111 generate an output potential during the calibration process. The temperature control unit 112 controls the temperature inside the sealed box 111. As the temperature of the sealed box 111 changes, the temperatures of the thin film thermocouple to be calibrated 121 and the standard thin film thermocouple 122 change accordingly. Ideally, the temperatures of the two thin film thermocouples change synchronously. The output potentials of multiple sampling points are measured for static calibration of the thin film thermocouple to be calibrated 121.

[0035] When using thin film thermocouples for temperature detection, in addition to using the above-mentioned static calibration method to obtain the corresponding relationship between temperature and output potential, it is also necessary to understand the dynamic performance of the thin film thermocouple to determine the applicable occasions of the thin film thermocouple.

[0036] Dynamic performance refers to the potential output of a thin-film thermocouple when it receives a large amount of energy in a very short period of time and experiences a rapid temperature increase. Transient response time is typically used to reflect this potential output, and this can be measured using dynamic calibration methods. Transient response time is divided into two parts: pre-response time and post-response time. Pre-response time is the time period from the start of energy input until the output potential is generated; post-response time is the time period from the start of the output potential until the output potential reaches its peak as the temperature rises.

[0037] The dynamic calibration method adopted in the embodiment of the present invention is a pulse signal response method, wherein the excitation heat source is a pulse laser, which can output a large amount of energy in a very short time to provide the thin film thermocouple with temperature increase.

[0038] The pulse laser source module 13 is used to generate pulse laser B. During dynamic calibration, the pulse laser B is made to illuminate the thin film thermocouple 121 to be calibrated through the light-transmitting window A while irradiating the photodetector 14, thereby ensuring that the thin film thermocouple 121 to be calibrated and the photodetector 14 synchronously obtain the same energy input at the same time. Subsequently, the output potential of the photodetector 14 is obtained at multiple sampling points. According to the corresponding relationship between the temperature and the output potential of the photodetector 14, a plot is drawn and fitted, and the corresponding relationship between the temperature of the photodetector 14 and the sampling time can be obtained.

[0039] Similarly, the output potential of the thin-film thermocouple 121 to be calibrated is obtained at these sampling points. Based on the corresponding relationship between the temperature of the thin-film thermocouple 121 to be calibrated and the output potential, a plot is drawn and fitted to obtain the corresponding relationship between the temperature of the thin-film thermocouple 121 to be calibrated and the sampling time. Finally, by comparing these two temperature-sampling time corresponding relationship graphs, the aforementioned transient response time can be obtained.

[0040] In addition, before using the photodetector 14 to dynamically calibrate the thin-film thermocouple 121 to be calibrated, the photodetector 14 must also be statically calibrated. Specifically, the pulsed laser light B generated by the pulsed laser source module 13 is used to simultaneously heat the thin-film thermocouple 121 to be calibrated and the photodetector 14. The output potentials of the two devices are measured. Based on the correspondence between the temperature and output potential of the statically calibrated thin-film thermocouple 121 to be calibrated, the correspondence between the temperature and output potential of the photodetector 14 is then determined, thereby achieving static calibration of the photodetector 14.

[0041] In the system for static and dynamic calibration of thin-film thermocouples provided in the above-mentioned embodiment, the temperature control unit 112 of the temperature control box module 11 can adjust the temperature inside the sealed box 111, so that the thin-film thermocouple 121 to be calibrated and the standard thin-film thermocouple 122 located inside the sealed box 111 generate an output potential at the output end when the temperature changes. By measuring the output potential and based on the temperature-output potential correspondence of the standard thin-film thermocouple 122, static calibration of the thin-film thermocouple 121 to be calibrated can be achieved.

[0042] In addition, the pulse laser B generated by the pulse laser source module 13 can irradiate the thin film thermocouple 121 to be calibrated through the light-transmitting window A on the sealed box 111, and at the same time, the pulse laser B irradiates the photodetector 14 located outside the sealed box 111, so that the thin film thermocouple 121 to be calibrated and the photodetector 14 are heated at the same time, and the output potential of the thin film thermocouple 121 to be calibrated and the output potential of the photodetector 14 are measured. According to the temperature-output potential correspondence of the statically calibrated thin film thermocouple 121 to be calibrated, the static calibration of the photodetector 14 can be achieved.

[0043] Finally, the pulse laser B generated by the pulse laser source module 13 is used to simultaneously heat the thin film thermocouple 121 to be calibrated and the photodetector 14 that has been statically calibrated, and the output potential of the thin film thermocouple 121 to be calibrated and the output potential of the photodetector 14 are measured. Based on the temperature-output potential correspondence of the statically calibrated photodetector 14, dynamic calibration of the thin film thermocouple 121 to be calibrated can be achieved.

[0044] Therefore, the above system integrates the static calibration and dynamic calibration of the thin film thermocouple to be calibrated, and can complete the static and dynamic calibration of the thin film thermocouple to be calibrated on one platform. There is no need to transfer the thin film thermocouple to be calibrated between different platforms, which can prevent the thin film thermocouple to be calibrated from being damaged due to transfer; the structure is simple, the operation is convenient, and the error introduced during the operation is reduced.

[0045] The above system may also include Figure 1 The data collector 16 shown is connected to the first output end 124 of the thin film thermocouple to be calibrated 121, the second output end 126 of the standard thin film thermocouple 122 and the third output end 127 of the photodetector 14, and is used to collect the output potentials of the thin film thermocouple to be calibrated 121, the standard thin film thermocouple 122 and the photodetector 14. The collection time interval can be set as needed, so that the output potentials of multiple sampling points can be obtained during the collection process.

[0046] The temperature control unit 112 may include a first control device 1121, a water cooling device 1122 connected to the first control device 1121, and a heating device 1123. The water cooling device 1122 is partially embedded in the wall of the sealed box 111 and is used to cool the interior of the sealed box 111. The heating device 1123 is disposed within the sealed box 111 and is used to increase the temperature of the interior of the sealed box 111. By controlling the water cooling device 1122 and the heating device 1123 through the first control device 1121, the temperature inside the sealed box 111 can be adjusted.

[0047] In the above system, the thin film thermocouple to be calibrated 121 and the standard thin film thermocouple 122 can be symmetrically arranged on both sides of the heating device 1123. The advantage of the symmetrical arrangement is that the thin film thermocouple to be calibrated 121 and the standard thin film thermocouple 122 are at equal distances from the heating device 1123, and the temperatures at the locations of the two thermocouples remain consistent, thereby reducing calibration errors.

[0048] The heating device can be a graphite heater, in which the graphite sheet is the primary heat-generating component, and has high thermal efficiency. When a graphite heater is used as the heating device, the system can also include a vacuum pump 17 connected to the first control device 1121 and the sealed box 111, which is used to cause the first control device 1121 to evacuate the interior of the sealed box 111. This evacuation is intended to prevent oxidation of the graphite sheet at high temperatures.

[0049] In addition, in the above embodiment, the pulse laser source module 13 may include a spectrometer 131, a second control device 132 and a pulse laser 133 connected to each other. The second control device 132 is used to control the pulse laser 133 to generate pulse laser B; the spectrometer 131 is used to divide the pulse laser B into two parts, respectively irradiating the thin film thermocouple 121 to be calibrated and the photodetector 14. The spectrometer 131 may include Figure 1 The one beam splitter and two lenses shown may also be other structures known to those skilled in the art for equally splitting a laser beam.

[0050] The embodiment of the present invention also provides a method for static and dynamic calibration of thin film thermocouples, using the system for static and dynamic calibration of thin film thermocouples provided by the above embodiment, specifically as follows Figure 2 As shown, the following steps are included.

[0051] Step 201: Use the temperature control box module 11 to adjust the internal temperature of the sealed box 111, and measure the output potential of the first output terminal 124 and the second output terminal 126 of the thermocouple module 12, so that the thin film thermocouple 121 to be calibrated in the thermocouple module 12 is statically calibrated according to the corresponding relationship between the temperature and the output potential of the standard thin film thermocouple 122.

[0052] Here, a comparison method is used to statically calibrate the thin film thermocouple to be calibrated 121. Specifically, the thin film thermocouple to be calibrated 121 and the standard thin film thermocouple 122 are placed inside the sealed box 111 (here, for the sake of clarity, the hot ends of the two thin film thermocouples located inside the sealed box are referred to as the thin film thermocouple to be calibrated 121 and the standard thin film thermocouple 122). A first cold end 123 extending from the thin film thermocouple to be calibrated to the outside of the sealed box 111 and a second cold end 125 extending from the standard thin film thermocouple 122 to the outside of the sealed box 111 are placed in a zero-degree thermostat 15 to ensure that the temperature of the cold ends is constant at 0°C.

[0053] A first output terminal 124 extending from the thin film thermocouple 121 to be calibrated to the outside of the sealed box 111 and a second output terminal 126 extending from the standard thin film thermocouple 122 to the outside of the sealed box 111, during the calibration process, these two output terminals generate output potentials. The temperature control unit 112 controls the temperature inside the sealed box 111. During the temperature change of the sealed box 111, the temperature of the thin film thermocouple 121 to be calibrated and the standard thin film thermocouple 122 change accordingly. The ideal state is that the temperature of the two thin film thermocouples changes synchronously. The output potentials of the two thin film thermocouples at multiple sampling points are measured to obtain a set of output potential data. According to the correspondence between the known temperature and the output potential of the standard thin film thermocouple 122, the temperature value of each sampling point can be obtained, thereby obtaining the temperature and corresponding output potential of the thin film thermocouple 121 to be calibrated at each sampling point. These sampling points are plotted in the temperature-output potential diagram, and the correspondence between the temperature and the output potential of the thin film thermocouple 121 to be calibrated is finally obtained by fitting (i.e. Figure 3 The “static calibration curve of the thin film thermocouple to be calibrated” is shown in FIG), thereby completing the static calibration of the thin film thermocouple to be calibrated 121.

[0054] Step 202: Use the pulsed laser generated by the pulsed laser source module 13 to simultaneously irradiate the thin film thermocouple 121 to be calibrated and the photodetector 14, and measure the output potential of the first output terminal 124 and the third output terminal 127 of the photodetector, so that the photodetector 14 is statically calibrated according to the corresponding relationship between the temperature and the output potential of the thin film thermocouple 121 to be calibrated.

[0055] Specifically, the pulsed laser B generated by the pulsed laser source module 13 is used to simultaneously irradiate the thin film thermocouple 121 to be calibrated and the photodetector 14, thereby simultaneously heating the thin film thermocouple 121 to be calibrated and the photodetector 14, and measuring the output potential of the two devices at multiple sampling points. Then, based on the correspondence between the temperature and the output potential of the statically calibrated thin film thermocouple 121 to be calibrated, the temperature value of each sampling point can be obtained, thereby obtaining the temperature and the corresponding output potential of the photodetector 14 at each sampling point. These sampling points are plotted in the temperature-output potential diagram, and the correspondence between the temperature and the output potential of the photodetector 14 is finally obtained by fitting (i.e. Figure 3 ). This allows for static calibration of the photodetector 14.

[0056] 203. Use the pulse laser B generated by the pulse laser source module 13 to simultaneously irradiate the thin film thermocouple 121 to be calibrated and the photodetector 14, and measure the output potential of the first output terminal 124 and the third output terminal 127 of the photodetector 14, so that the thin film thermocouple 121 to be calibrated is dynamically calibrated according to the corresponding relationship between the temperature and the output potential of the photodetector 14.

[0057] Specifically, the pulse laser B generated by the pulse laser source module 13 is used to irradiate the thin film thermocouple 121 to be calibrated through the light-transmitting window A, and also irradiates the photodetector 14, so as to ensure that the thin film thermocouple 121 to be calibrated and the photodetector 14 synchronously obtain the same energy input at the same time. Then, the output potential of the photodetector 14 is obtained at multiple sampling points to form a corresponding relationship curve between the output potential V and the sampling time t (i.e. Figure 3 According to the corresponding relationship between the temperature T of the photodetector 14 and the output potential of the statically calibrated photodetector 14, a corresponding relationship curve between the temperature T of the photodetector 14 and the sampling time t can be obtained (ie, Figure 3 ”32” shown in the figure).

[0058] Similarly, the output potential of the thin film thermocouple 121 to be calibrated is also obtained at these sampling points to form a corresponding relationship curve between the output potential V and the sampling time t (ie Figure 3 33), according to the corresponding relationship between the temperature of the thin film thermocouple 121 to be calibrated and the output potential, a plot is made and fitted, and the corresponding relationship between the temperature T of the thin film thermocouple 121 to be calibrated and the sampling time t can be obtained (i.e. Figure 3 Finally, by comparing the two temperature-sampling time correspondence diagrams, the transient response time can be obtained to achieve dynamic calibration.

[0059] In the method for static and dynamic calibration of thin-film thermocouples provided in the above embodiment, the temperature control unit 112 of the temperature control box module 11 can adjust the temperature inside the sealed box 111, so that the thin-film thermocouple 121 to be calibrated and the standard thin-film thermocouple 122 located inside the sealed box 111 generate an output potential at the output end when the temperature changes. By measuring the output potential and based on the temperature-output potential correspondence of the standard thin-film thermocouple 122, static calibration of the thin-film thermocouple 121 to be calibrated can be achieved.

[0060] In addition, the pulse laser B generated by the pulse laser source module 13 can irradiate the thin film thermocouple 121 to be calibrated through the light-transmitting window A on the sealed box 111, and at the same time, the pulse laser B irradiates the photodetector 14 located outside the sealed box 111, so that the thin film thermocouple 121 to be calibrated and the photodetector 14 are heated at the same time, and the output potential of the thin film thermocouple 121 to be calibrated and the output potential of the photodetector 14 are measured. According to the temperature-output potential correspondence of the statically calibrated thin film thermocouple 121 to be calibrated, the static calibration of the photodetector 14 can be achieved.

[0061] Finally, the pulse laser B generated by the pulse laser source module 13 is used to simultaneously heat the thin film thermocouple 121 to be calibrated and the photodetector 14 that has been statically calibrated, and the output potential of the thin film thermocouple 121 to be calibrated and the output potential of the photodetector 14 are measured. Based on the temperature-output potential correspondence of the statically calibrated photodetector 14, dynamic calibration of the thin film thermocouple 121 to be calibrated can be achieved.

[0062] Therefore, the above method integrates the static calibration and dynamic calibration of the thin film thermocouple to be calibrated, and can complete the static and dynamic calibration of the thin film thermocouple to be calibrated on one platform. There is no need to transfer the thin film thermocouple to be calibrated between different platforms, which can prevent the thin film thermocouple to be calibrated from being damaged due to transfer; the structure is simple, the operation is convenient, and the error introduced during the operation is reduced.

[0063] Between step 201 and step 202 , the pulse laser source module 13 may be preheated, and the power and pulse frequency of the pulse laser B may be adjusted to make the generated pulse laser B suitable for different calibration processes.

[0064] In addition, in the above step 203, the sampling frequency of measuring the output potential of the first output terminal 124 and the third output terminal 127 of the photodetector can be 5 to 10 times the pulse frequency of the pulse laser B, in order to obtain more accurate dynamic calibration results.

[0065] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A system for static and dynamic calibration of thin film thermocouples, characterized in that: It includes a temperature control box module, a thermocouple module, a pulse laser source module including a spectrometer, a photodetector and a zero-degree thermostat; The temperature control box module includes a sealed box body with a light-transmitting window and a temperature control unit, and the temperature control unit is used to control the temperature inside the sealed box body; The thermocouple module includes a thin film thermocouple to be calibrated and a standard thin film thermocouple located inside the sealed box, a first cold end and a first output end connected to the thin film thermocouple to be calibrated and extending to the outside of the sealed box, and a second cold end and a second output end connected to the standard thin film thermocouple and extending to the outside of the sealed box; the first cold end and the second cold end are placed in the zero-degree thermostat; The standard thin film thermocouple is used to perform static calibration on the thin film thermocouple to be calibrated; The pulse laser source module is used to generate a pulse laser, and after the pulse laser is split into equal parts, a part of it illuminates the thin film thermocouple to be calibrated through the light-transmitting window, and the other part simultaneously illuminates the photodetector, so that the photodetector is statically calibrated using the result of static calibration of the thin film thermocouple to be calibrated using the standard thin film thermocouple, and the thin film thermocouple to be calibrated is dynamically calibrated using the statically calibrated photodetector.

2. The system according to claim 1, wherein: It also includes a data collector connected to the first output end, the second output end and the third output end of the photoelectric detector.

3. The system according to claim 1, wherein: The temperature control unit includes a first control device, a water cooling device and a heating device connected to the first control device; the water cooling device is partially embedded in the box wall of the closed box; and the heating device is arranged inside the closed box.

4. The system according to claim 3, characterized in that The thin film thermocouple to be calibrated and the standard thin film thermocouple are symmetrically arranged on both sides of the heating device.

5. The system according to claim 3, wherein: The heating device is a graphite heater.

6. The system according to claim 5, characterized in that It also includes a vacuum pump connected to the first control device and the closed box, which is used to enable the first control device to vacuum the inside of the closed box.

7. The system according to any one of claims 1 to 6, characterized in that: The pulse laser source module further includes a second control device and a pulse laser that are connected to each other; the second control device is used to control the pulse laser to generate the pulse laser.

8. A method for static and dynamic calibration of a thin film thermocouple, characterized in that: include: (1) using a temperature control box module to adjust the internal temperature of the sealed box, and measuring the output potential of the first output end and the second output end of the thermocouple module, so that the thin film thermocouple to be calibrated in the thermocouple module is statically calibrated according to the corresponding relationship between the temperature and the output potential of the standard thin film thermocouple; (2) using a pulsed laser generated by a pulsed laser source module and splitting the light equally, with one portion irradiating the thin film thermocouple to be calibrated through a light-transmitting window provided on the sealed box, while the other portion irradiates a photodetector, and measuring the output potential of the first output terminal and the third output terminal of the photodetector, so that the photodetector is statically calibrated according to the corresponding relationship between the temperature and the output potential of the thin film thermocouple to be calibrated; (3) The pulsed laser generated by the pulsed laser source module is used to split the light into equal parts, with one part irradiating the thin film thermocouple to be calibrated through a light-transmitting window provided on the sealed box, while the other part irradiates the photodetector, and the output potential of the first output terminal and the third output terminal of the photodetector is measured, so that the thin film thermocouple to be calibrated is dynamically calibrated according to the corresponding relationship between the temperature and the output potential of the photodetector.

9. The method according to claim 8, characterized in that Between step (1) and step (2), the method further includes preheating the pulse laser source module and adjusting the power and pulse frequency of the pulse laser.

10. The method according to claim 8, characterized in that In the step (3), the sampling frequency for measuring the output potential of the first output terminal and the third output terminal of the photodetector is 5 to 10 times the pulse frequency of the pulse laser.

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