Measurement system and measurement method suitable for alignment and calibration

Abstract

The present application relates to the field of measurement, and provides a measurement system and a measurement method suitable for comparison and calibration. The measurement system suitable for comparison and calibration comprises a chamber, the chamber is closed; a heat conduction block, the heat conduction block is arranged in the chamber, and the heat conduction block is provided with a mounting hole for mounting a thermometer; a pressure control device, the pressure control device is connected with the chamber and is used for adjusting the pressure inside the chamber; a refrigeration device, the refrigeration device is connected with the chamber and is used for cooling the chamber; and resistance detection devices, the resistance detection devices are arranged as at least two, and the resistance detection devices are used for detecting the resistance value of the corresponding thermometer. The resistance values of at least two thermometers can be detected through the at least two resistance detection devices, and the thermometers can be compared or calibrated based on the resistance values of the thermometers.

Description

Technical Field

[0001] This invention relates to the field of measurement technology, and in particular to a measurement system and method suitable for comparison and calibration. Background Technology

[0002] Thermodynamic temperature is one of the seven base units of the International System of Units (SI). Low temperatures, especially the deep cryogenic region below 24.5561 K, are crucial for discovering new scientific phenomena and exploring new principles. They are also essential for creating extremely low background thermal noise, extreme currents, and magnetic fields. Therefore, high-accuracy thermodynamic temperature measurements below 24.5561 K are of great significance for cutting-edge scientific research, the operation of large scientific facilities, and national defense security.

[0003] To achieve high-precision temperature measurement and control, and to ensure the consistency of temperature values ​​globally, it is necessary to calibrate and compare the temperature readings of the thermometers.

[0004] Temperature calibration refers to the process of transferring temperature data from a highly accurate reference thermometer to the thermometer to be calibrated, so that the temperature to be calibrated also has the corresponding accuracy.

[0005] Temperature comparison refers to acquiring the temperature values ​​measured by various thermometers to be compared, and converting the readings of different thermometers to the same standard temperature value to achieve an agreed temperature, thus laying the foundation for the formation of international temperature calibration.

[0006] The technical problem to be solved by the present invention is to provide a measurement system that can both perform temperature comparison and temperature calibration. Summary of the Invention

[0007] This invention provides a measurement system and method suitable for comparison and calibration, which can realize both temperature comparison and temperature calibration.

[0008] This invention provides a measurement system suitable for comparison and calibration, comprising:

[0009] The chamber is enclosed;

[0010] A heat-conducting block is disposed in the chamber, and the heat-conducting block is provided with mounting holes for mounting a thermometer;

[0011] A pressure control device is connected to the chamber and is used to adjust the pressure inside the chamber;

[0012] A refrigeration device, which is connected to the chamber and is used to cool the chamber;

[0013] A resistance detection device, wherein at least two resistance detection devices are configured, and the resistance detection devices are used to detect the resistance value of the corresponding thermometer.

[0014] According to the present invention, a measurement system for comparison and calibration further includes a gating device, wherein the resistance detection device is connected to a corresponding thermometer through the corresponding gating device, and at least one resistance detection device is connected to at least two thermometers through the corresponding gating device, wherein the gating device is configured to selectively connect any one thermometer to the resistance detection device, or disconnect all thermometers from the resistance detection device.

[0015] According to the present invention, a measurement system for comparison and calibration further includes a connector. The chamber includes a cylinder and a flange. The cylinder has an opening. The flange is connected to the cylinder and closes the opening. The connector is made of heat-insulating material and connects the cylinder and the heat-conducting block.

[0016] According to the present invention, a measurement system for comparison and calibration further includes a vacuum plug disposed in the chamber, a resistance detection device disposed outside the chamber, and a lead of the resistance detection device extending into the chamber through the vacuum plug and connected to a corresponding thermometer.

[0017] According to the present invention, a measurement system for comparison and calibration is provided, wherein the pressure control device includes a vacuum pumping device and a gas source, both of which are connected to the chamber. The vacuum pumping device is used to pump gas from the chamber, and the gas source is used to introduce low-temperature working gas into the chamber.

[0018] The present invention also provides a measurement method based on a measurement system suitable for comparison and calibration as described above, the measurement method comprising:

[0019] The thermometer is placed into the mounting hole of the heat-conducting block, and the chamber is cooled by the cooling device.

[0020] The thermometer is subjected to excitation current for at least three time periods, wherein the excitation current of the first time period and the excitation current of the last time period are equal, and the excitation current of the first time period and the excitation current of the last time period are both less than the excitation current of the middle time period. The corresponding resistance value of the thermometer in each time period is detected by the resistance detection device.

[0021] The thermometer is calibrated or compared based on its resistance value.

[0022] According to a measurement method provided by the present invention, an excitation current is applied to a thermometer for at least three time periods, comprising:

[0023] At least three time periods of excitation current are applied to each thermometer in sequence. When the excitation current is applied to any two thermometers in sequence, if the excitation current applied to the previous thermometer is in the middle time period, the excitation current applied to the next thermometer is in the first time period, and the middle time periods of the excitation current applied to the two thermometers are staggered.

[0024] According to a measurement method provided by the present invention, a thermometer is compared based on its resistance value, comprising:

[0025] At least one thermometer is used as a reference thermometer, and the reference temperature value detected by the reference thermometer is obtained based on the resistance value of the reference thermometer.

[0026] Based on the resistance values ​​of the other thermometers, obtain the temperature value detected by each thermometer;

[0027] Calculate the deviation between the temperature values ​​measured by the other thermometers and the reference temperature value.

[0028] According to a measurement method provided by the present invention, a thermometer is compared based on its resistance value, comprising:

[0029] Based on the resistance value of each thermometer, obtain the temperature value detected by each thermometer;

[0030] The weighted average temperature value is obtained by taking a weighted average of the temperature values ​​measured by all thermometers.

[0031] Calculate the deviation between the temperature value measured by each thermometer and the weighted average temperature value.

[0032] According to a measurement method provided by the present invention, a thermometer is calibrated based on a resistance value, comprising:

[0033] At least one thermometer is used as a reference thermometer, and the reference temperature value detected by the reference thermometer is obtained based on the resistance value of the reference thermometer.

[0034] The resistance values ​​of the remaining thermometers are fitted to the reference temperature value to obtain the corresponding resistance-temperature curves for the remaining thermometers.

[0035] The measurement system provided by this invention, suitable for comparison and calibration, provides a closed space through a sealed chamber, reducing heat exchange between the inside and outside of the chamber and improving measurement accuracy. A cooling device lowers the temperature of the chamber, creating a low-temperature environment for thermometer measurements. By incorporating a heat-conducting block within the chamber, the block achieves uniform temperature and a small temperature gradient, ensuring all thermometers mounted on it operate at the same temperature. A pressure control device can adjust the vacuum level of the chamber or introduce low-temperature gas to achieve rapid cooling of the heat-conducting block and improve its temperature uniformity.

[0036] The resistance values ​​of at least two thermometers can be detected by at least two resistance detection devices, and the thermometers can be compared or calibrated based on the resistance values ​​of the thermometers.

[0037] The measurement method provided by this invention, being implemented based on the measurement system provided by this invention, thus simultaneously incorporates all the aforementioned advantages of the measurement system. Attached Figure Description

[0038] To more clearly illustrate the technical solutions in this invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of this invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0039] Figure 1 This is a schematic diagram of the structure of a measurement system suitable for comparison and calibration provided in some embodiments of the present invention;

[0040] Figure 2 This is a schematic diagram of the loading process in some embodiments of the present invention, in which an excitation current is sequentially applied to each of the five thermometers by four resistance detection devices.

[0041] Figure 3 This is a schematic diagram of the loading process in some embodiments of the present invention, in which an excitation current is sequentially applied to each of five or more thermometers by using four resistance detection devices to detect five or more thermometers.

[0042] Figure 4 This is a schematic diagram of the loading process in some embodiments of the present invention, in which an excitation current is sequentially applied to each of the five thermometers by using five resistance detection devices to detect five thermometers.

[0043] Figure 5 This is a schematic diagram of the loading process in some embodiments of the present invention, in which an excitation current is sequentially applied to each of the five thermometers by three resistance detection devices.

[0044] Figure 6 This is a schematic diagram of the loading process in some embodiments of the present invention, in which an excitation current is sequentially applied to each of the five thermometers by two resistance detection devices.

[0045] Figure 7 This is a schematic diagram of the excitation current in the form of I-XI-I provided in some embodiments of the present invention.

[0046] Figure label:

[0047] 1. Chamber; 101. Cylinder; 102. Flange; 2. Heat-conducting block; 3. Thermometer; 4. Pressure control device; 5. Refrigeration device; 6. Resistance detection device; 7. Gating device; 8. Vacuum plug. Detailed Implementation

[0048] To make the objectives, technical solutions, and advantages of this invention clearer, the technical solutions of this invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of this invention. All other embodiments obtained by those skilled in the art based on the embodiments of this invention without creative effort are within the scope of protection of this invention.

[0049] The following is combined with Figures 1 to 7 A measurement system suitable for comparison and calibration is described in the embodiments of the present invention.

[0050] Specifically, the measurement system suitable for comparison and calibration includes a chamber 1, a heat-conducting block 2, a pressure control device 4, a cooling device 5, and a resistance detection device 6.

[0051] The chamber 1 is enclosed. Optionally, the chamber 1 is a shell structure. The interior of the chamber 1 forms a measurement space. The chamber 1 is made of insulating material to reduce heat exchange between the inside and outside of the chamber 1.

[0052] A heat-conducting block 2 is disposed within the chamber 1, and the heat-conducting block 2 is provided with mounting holes for mounting a thermometer 3. Optionally, there are multiple mounting holes, and the thermometer 3 can be placed into the corresponding mounting holes. Optionally, the heat-conducting block 2 is made of a low-temperature, high-thermal-conductivity material such as high-conductivity oxygen-free copper to reduce the temperature gradient of the heat-conducting block 2 and improve the temperature uniformity of the heat-conducting block 2. Optionally, the heat-conducting block 2 is configured as a solid structure or a cavity structure, and the heat-conducting block 2 is configured as a cylinder, prism, or sphere.

[0053] The pressure control device 4 is connected to the chamber 1 and is used to adjust the pressure inside the chamber 1. Optionally, the pressure control device 4 is configured to be able to evacuate the gas inside the chamber 1 to create a vacuum effect inside the chamber 1, and can also fill the chamber 1 with cryogenic working gases such as helium, neon or argon to rapidly cool down the heat-conducting block 2 and ensure the temperature uniformity of the heat-conducting block 2.

[0054] The refrigeration unit 5 is connected to the chamber 1 and is used to cool the chamber 1. For example, the refrigeration unit 5 is configured as a JT throttling refrigerator, a GM pulse tube refrigerator, a GM refrigerator, a dilution refrigerator, or an adiabatic demagnetizing refrigerator.

[0055] The number of resistance detection devices 6 is set to at least two. Each resistance detection device 6 is connected to a corresponding thermometer 3 and is used to detect the resistance value of the corresponding thermometer 3. Optionally, the resistance detection device 6 is configured as a bridge circuit, such as, but not limited to, an AC temperature measurement bridge and a DC temperature measurement bridge. The resistance detection device 6 can also be configured as a multimeter. The resistance detection device 6 is connected to the corresponding thermometer 3 using a four-wire lead measurement method to eliminate the influence of the lead resistance on the measurement results.

[0056] Optionally, the thermometer 3 includes, but is not limited to, positive temperature coefficient resistance thermometers 3 such as standard platinum resistance thermometer 3, standard rhodium iron resistance thermometer 3, standard platinum cobalt resistance thermometer 3, industrial rhodium iron resistance thermometer 3 and industrial platinum cobalt resistance thermometer 3, as well as negative temperature coefficient resistance thermometers 3 such as Cernox thermometer 3, ruthenium oxide thermometer 3, carbon resistance thermometer 3, germanium resistance thermometer 3, and application-grade thermometers 3 such as diode thermometer 3, capacitor thermometer 3, thermocouple thermometer 3, noise thermometer 3, magnetic thermometer 3 and quartz tuning fork thermometer 3.

[0057] The process of using the above measurement system includes:

[0058] The measurement system suitable for comparison and calibration provided in this embodiment of the invention provides a closed space through the enclosed chamber 1, reducing heat exchange between the inside and outside of the chamber 1 and improving measurement accuracy. The cooling device 5 can cool the chamber 1, creating a low-temperature environment inside the chamber 1, which facilitates measurement of the thermometer 3 in a low-temperature environment. By setting a heat-conducting block 2 inside the chamber 1, the temperature of the heat-conducting block 2 is uniform and the temperature gradient is small, so that all thermometers 3 installed on the heat-conducting block 2 can be in the same temperature environment. The pressure control device 4 can adjust the vacuum degree of the chamber 1 or introduce low-temperature gas into the chamber 1 to achieve rapid cooling of the heat-conducting block 2 and improve the temperature uniformity of the heat-conducting block 2.

[0059] The resistance values ​​of at least two thermometers 3 can be detected by at least two resistance detection devices 6, and the thermometers 3 can be compared or calibrated based on their resistance values.

[0060] For example, during comparison, the temperature value detected by each thermometer 3 can be obtained based on its resistance value. By comparing the temperature value of each thermometer 3 with the reference value, the readings of each thermometer 3 can be converted to the same standard, which is conducive to reaching an agreed temperature and laying the foundation for the formation of international temperature standards. The reference value can be a weighted average temperature value calculated based on the temperature values ​​of each thermometer 3, or a reference temperature value detected by a reference thermometer.

[0061] For example, during calibration, at least one thermometer 3 is used as a reference thermometer. Based on the resistance value of the reference thermometer, a reference temperature value is obtained. The resistance values ​​of the remaining thermometers 3 are then fitted to the reference temperature value to obtain the corresponding resistance-temperature curves for the remaining thermometers 3. In this way, the temperature data of the reference thermometer can be transferred to the remaining thermometers 3. Optionally, when fitting the resistance values ​​of the thermometers 3 to the reference temperature value, a (normalized) polynomial, a (normalized) logarithmic function, a Chebyshev interpolation function, or other functional forms can be used for fitting.

[0062] Furthermore, the measurement system also includes a processing module, which is connected to all the resistance detection devices 6. The processing module compares and calibrates the thermometer 3 based on the resistance values ​​detected by the resistance detection devices 6; that is, both comparison and calibration are performed through the processing module. The processing module can be a computer or a processor.

[0063] In some embodiments provided by the present invention, the measurement system further includes a gating device 7. At least some resistance detection devices 6 are connected to corresponding thermometers 3 through corresponding gating devices 7, and at least one resistance detection device 6 is connected to at least two thermometers 3 through corresponding gating devices 7. The gating device 7 is configured to selectively connect any one thermometer 3 to the resistance detection device 6, or disconnect all thermometers 3 from the resistance detection device 6.

[0064] In this embodiment, the resistance detection device 6 is connected to the corresponding thermometer 3 via a corresponding gating device 7. The gating device 7 enables the resistance detection device 6 to be connected to or disconnected from the thermometer 3, for example, connected when it is necessary to detect the thermometer 3 and disconnected when it is not necessary to detect the thermometer 3. The resistance detection device 6 is connected to at least two thermometers 3 via the corresponding gating device 7, so that the resistance values ​​of at least two thermometers 3 can be detected by the resistance detection device 6, thereby reducing the number of resistance detection devices 6 used and reducing the cost of the measurement system.

[0065] Optionally, the gating device 7 is configured as a scan switch. For example... Figure 1 As shown, the scanning switch can be configured as an external scanning switch independent of the resistance detection device 6, or it can be configured as an internal scanning switch integrated into the resistance detection device 6.

[0066] In some embodiments provided by the present invention, the measuring system further includes a connector. The chamber 1 includes a cylindrical body 101 and a flange 102. The cylindrical body 101 has an opening, and the flange 102 is connected to the cylindrical body 101 and closes the opening. Optionally, the flange 102 and the cylindrical body 101 are detachably connected. For example, the flange 102 is threaded to the cylindrical body 101 or connected by threaded fasteners. The connector is made of a heat-insulating material and connects the cylindrical body 101 to the heat-conducting block 2.

[0067] In this embodiment, the opening of the cylinder 101 is located at the top. The heat-conducting block 2 is connected to the flange 102 via a connector. After the thermometer 3 is installed on the heat-conducting block 2, the heat-conducting block 2 is placed into the cylinder 101 through the opening, and the flange 102 is connected to the cylinder 101. The heat-conducting block 2 is suspended inside the cylinder 101 via the connector. The heat-conducting block 2 does not contact the cylinder 101, which reduces heat exchange between the heat-conducting block 2 and the cylinder 101, thereby making the temperature of the heat-conducting block 2 constant and with better temperature uniformity.

[0068] Optionally, the connector is configured as a connecting rod, with one end connected to the flange 102 and the other end connected to the heat-conducting block 2. The connecting rod has a small cross-sectional size, which can further reduce heat transfer to the heat-conducting block 2. Furthermore, the number of connecting rods is set to at least two to improve the stability of the suspension of the heat-conducting block 2.

[0069] Optionally, the cold head of the refrigeration device 5 is connected to the flange 102. That is, the cylinder 101 is made of heat-insulating material, and the flange 102 is made of heat-conducting material. The cold head of the refrigeration device 5 transfers cooling energy to the cylinder 101 through the flange 102, thus reducing heat exchange between the cylinder 1 and the outside environment. This configuration reduces the heat exchange area between the chamber 1 and the outside environment, thereby reducing temperature fluctuations within the chamber 1 and improving measurement accuracy.

[0070] In some embodiments provided by the present invention, the measuring system further includes a vacuum plug 8. The vacuum plug 8 is disposed in the chamber 1, for example, the vacuum plug 8 is disposed in the flange 102. The resistance detection device 6 is disposed outside the chamber 1, and the lead of the resistance detection device 6 extends into the chamber 1 through the vacuum plug 8 and is connected to a corresponding thermometer 3.

[0071] In this embodiment, by providing a vacuum plug 8, the leads can enter and exit through the vacuum plug 8, reducing heat conduction from the points where the leads enter and exit, thereby ensuring a stable temperature inside the chamber 1. Furthermore, placing the resistance detection device 6 outside the chamber 1 avoids its influence on the temperature inside the chamber 1, reduces its space occupation, and prevents the low temperature inside the chamber 1 from affecting the resistance detection device 6.

[0072] In some embodiments of the present invention, the pressure control device 4 includes a vacuum pump and a gas source. Both the vacuum pump and the gas source are connected to the chamber 1. The vacuum pump is used to evacuate the gas inside the chamber 1 to create a vacuum, and the gas source is used to introduce a cryogenic working gas into the chamber 1. For example, the cryogenic working gas includes, but is not limited to, helium, neon, and argon. The pressure range of the cryogenic working gas is 0 kPa to 10 kPa. This is to achieve rapid cooling of the heat-conducting block 2 and improve the temperature uniformity of the heat-conducting block 2.

[0073] Optionally, both the vacuum pump and the gas source are connected to chamber 1 via solenoid valves.

[0074] In some embodiments of the present invention, a metal foil layer, such as copper foil or indium foil, is filled between the mounting hole and the thermometer 3. For example, the metal foil layer can be wrapped around the outside of the thermometer 3 before the thermometer 3 is placed into the mounting hole of the heat-conducting block 2. The metal foil layer has good flexibility and can fill the gap between the mounting hole and the thermometer 3, thus ensuring good thermal conductivity between the thermometer 3 and the heat-conducting block 2. Furthermore, low-temperature grease is filled between the metal foil layer and the mounting hole, as well as between the metal foil layer and the thermometer 3. The low-temperature grease can fill the gap between the metal foil layer and the mounting hole, and between the metal foil layer and the thermometer 3, ensuring good thermal conductivity between the thermometer 3 and the heat-conducting block 2.

[0075] An embodiment of the present invention also provides a measurement method. Specifically, the measurement method is implemented based on a measurement system suitable for comparison and calibration as described above.

[0076] The measurement methods include:

[0077] First, the thermometer 3 is placed into the mounting hole of the heat-conducting block 2, and the chamber 1 is cooled by the cooling device 5.

[0078] Specifically, the thermometer 3 is placed into the mounting hole of the heat-conducting block 2, and the resistance measuring device is connected to the corresponding thermometer 3. Then, the cooling device 5 is turned on to cool the chamber 1.

[0079] Second, apply excitation current to thermometer 3 for at least three time periods. The excitation current in the first time period is equal to the excitation current in the last time period, meaning their current values ​​are the same. The excitation current in the first and last time periods is less than the excitation current in the middle time periods. The resistance value of thermometer 3 in each time period is detected by resistance detection device 6.

[0080] Specifically, the resistance detection device 6 can be used to apply an excitation current to the corresponding thermometer 3 so that the thermometer 3 can self-heat.

[0081] Optionally, refer to Figures 2-7As shown, the excitation current can be set as a three-segment excitation current in the form of I-XI-I. The excitation current I ranges from 1μA to 100mA, and the real number X ranges from √2 to 10. The duration of each of the three excitation current segments is a unit duration, ranging from 5 minutes to 200 minutes. Applying excitation current I at the first and last time segments eliminates potential temperature drift, hysteresis, and ambient temperature changes, ensuring the reliability of the measurement results. The excitation current XI for the middle time segment is set because of the self-heating effect of the thermometer 3. Different excitation currents measure different resistances, corresponding to different temperatures. Using two different excitation currents allows extrapolation to obtain the resistance at zero current, thus correcting for the self-heating effect and eliminating its influence on the detection results.

[0082] Of course, the excitation current is not limited to the I-XI-I form described above. For example, the excitation current can also be set to the form I-XI-YI-I or I-XI-YI-XI-I. The excitation current I ranges from 1μA to 100mA, the real number X ranges from √2 to 10, and the real number Y ranges from √2 to 10, with X less than Y. The excitation current in the first and last time periods lasts for one unit of time. If there are two or three excitation currents in the middle time periods, each excitation current lasts for one unit of time, meaning the excitation current in the middle time periods lasts for a total of two or three unit of time. The unit of time ranges from 5 minutes to 200 minutes. Repeating the excitation current I or XI twice is to eliminate potential temperature drift, hysteresis effects, and changes in ambient temperature, ensuring the reliability of the measurement results. The excitation currents XI and YI for the intermediate time period are set because of the self-heating effect of thermometer 3. Different excitation currents measure different resistances and corresponding temperatures. By using two excitation currents of different magnitudes, the resistance at zero current can be extrapolated, which can correct the self-heating effect and eliminate the influence of self-heating on the detection results.

[0083] Third, calibrate or compare the thermometer 3 based on its resistance value.

[0084] Specifically, during the comparison, the temperature value detected by each thermometer 3 can be obtained based on its resistance value. By comparing the temperature value of each thermometer 3 with the reference value, the readings of each thermometer 3 can be converted to the same standard, which is conducive to reaching an agreed temperature and laying the foundation for the formation of international temperature standards. The reference value can be a weighted average temperature value calculated based on the temperature values ​​of each thermometer 3, or a reference temperature value detected by a reference thermometer.

[0085] Specifically, during calibration, at least one thermometer 3 is used as a reference thermometer. Based on the resistance value of the reference thermometer, a reference temperature value is obtained. The resistance values ​​of the remaining thermometers 3 are then fitted to the reference temperature value to obtain the corresponding resistance-temperature curves for the remaining thermometers 3. In this way, the temperature data of the reference thermometer can be transferred to the remaining thermometers 3. Optionally, when fitting the resistance values ​​of the thermometers 3 to the reference temperature value, a (normalized) polynomial, a (normalized) logarithmic function, a Chebyshev interpolation function, or other functional forms can be used for fitting.

[0086] The measurement method provided in this embodiment of the invention utilizes a sealed chamber 1 to provide a closed space, reducing heat exchange between the inside and outside of the chamber and improving measurement accuracy. A cooling device 5 cools the chamber 1, creating a low-temperature environment for thermometers 3 to measure within this environment. A heat-conducting block 2 is installed within the chamber 1, ensuring uniform temperature and a small temperature gradient, allowing all thermometers 3 mounted on the heat-conducting block 2 to operate at the same temperature. A pressure control device 4 can adjust the vacuum level of the chamber 1 or introduce low-temperature gas into the chamber 1 to achieve rapid cooling of the heat-conducting block 2 and improve its temperature uniformity. At least two resistance detection devices 6 can detect the resistance values ​​of at least two thermometers 3, enabling comparison or calibration of the thermometers 3 based on their resistance values.

[0087] By applying excitation current to thermometer 3 for at least three time periods, the resistance of thermometer 3 at zero current can be obtained, and possible temperature drift, hysteresis effect and changes in ambient temperature can be eliminated, ensuring the reliability of the measurement results.

[0088] refer to Figures 2-6 As shown, in some embodiments provided by the present invention, an excitation current is applied to the thermometer 3 for at least three time periods, including:

[0089] At least three time periods of excitation current are applied to each thermometer 3 in sequence. During the process of applying excitation current to any two thermometers 3 in sequence, when the excitation current applied to the previous thermometer 3 is in the middle time period, the excitation current applied to the next thermometer 3 is in the first time period, and the middle time periods of the excitation current applied to the two thermometers 3 are staggered.

[0090] In this embodiment, with Figure 1 and Figure 2Taking this example, we assume the excitation current is in the form of I-XI-I, and that thermometers 3 are A, B, C, D, and R. Thermometers A and D are connected to the same resistance detection device 6 via a gating device 7, allowing the resistance detection device 6 to detect the resistance of thermometers A and D respectively. Thermometers B and C are connected to their respective resistance detection devices 6 via their respective gating devices 7, and thermometer R is directly connected to its corresponding resistance detection device 6 as a reference thermometer.

[0091] An excitation current is applied to thermometer R. When the excitation current of thermometer R reaches XI, the excitation current of thermometer A reaches the first time period I. When the excitation current of thermometer R reaches the end of the time period, the excitation current of thermometer A reaches the middle time period XI. The principle used is that thermometers B, C, and D record the excitation current in sequence.

[0092] This configuration, on the one hand, allows for the staggering of the middle time intervals of the excitation current of any thermometer 3, preventing both thermometers 3 from simultaneously experiencing excitation current XI during measurement, thereby reducing mutual interference between thermometers 3. On the other hand, when the excitation current applied to the previous thermometer 3 is still in its middle segment, the excitation current of the first time segment is applied to the next thermometer 3, thus improving the measurement efficiency of the thermometers 3 and shortening the measurement time.

[0093] Optionally, such as Figure 3 The illustration shows an embodiment with five or more thermometers 3, where the excitation current remains in the I-XI-I configuration. Except for the resistance detection device 6 connected to the reference thermometer R, each of the other resistance detection devices 6 is connected to at least two thermometers 3 via a gating device 7. By controlling the gating state of each gating device 7, the resistance detection device 6 sequentially records the excitation current for each thermometer 3. In this configuration, the resistance detection device 6 operates at its highest efficiency in the measurement system, resulting in the highest detection efficiency.

[0094] Optionally, such as Figure 4 The example shown illustrates the use of five resistance sensing devices 6 to detect five thermometers 3. Figure 5 The image shows an example of using three resistance sensing devices 6 to detect five thermometers 3. Figure 6 The example shown is an example of using two resistance detection devices 6 to detect five thermometers 3.

[0095] Optionally, for an excitation current of the form I-XI-YI-I, when the excitation current of the previous thermometer 3 is in the YI time period, the excitation current I of the first time period is applied to the next thermometer 3. For an excitation current of the form I-XI-YI-XI-I, while applying the second excitation current XI of the middle time period to the previous thermometer 3, the excitation current I of the first time period is applied to the next thermometer 3.

[0096] In some embodiments provided by the present invention, the thermometer 3 is compared based on its resistance value, including:

[0097] First, at least one thermometer 3 is used as a reference thermometer, and the reference temperature value detected by the reference thermometer is obtained based on the resistance value of the reference thermometer.

[0098] Specifically, each reference thermometer has a defined resistance-temperature curve. Based on the resistance-temperature curve and the resistance value of the reference thermometer, the reference temperature value detected by the reference thermometer can be obtained.

[0099] Second, based on the resistance values ​​of the remaining thermometers 3, obtain the temperature value detected by each thermometer 3.

[0100] Specifically, the remaining thermometers 3 are the thermometers 3 to be compared. Each thermometer 3 to be compared has a corresponding resistance-temperature curve. Based on the resistance-temperature curve and its respective resistance value, the temperature value detected by each thermometer 3 to be calibrated can be obtained.

[0101] Third, calculate the deviation between the temperature value detected by the remaining thermometer 3 and the reference temperature value.

[0102] Specifically, by comparing the temperature value of each thermometer 3 to be calibrated with the reference temperature value of the reference thermometer, the equivalence of the temperature values ​​between each thermometer 3 and the reference thermometer can be obtained. This allows the readings of each thermometer 3 to be converted to the readings of the reference thermometer, which is beneficial for reaching a consensus on temperature and laying the foundation for the formation of international temperature standards. In addition, the reference thermometer can continuously measure the fluctuations in ambient temperature during the measurement process to correct for measurement errors introduced by ambient temperature fluctuations in real time, providing accuracy for the comparison.

[0103] Unlike the above embodiments where each thermometer 3 is compared with a reference thermometer, in other embodiments provided by the present invention, the thermometer 3 is calibrated based on its resistance value, including:

[0104] First, based on the resistance value of each thermometer 3, obtain the temperature value detected by each thermometer 3.

[0105] Specifically, thermometer 3 is the thermometer 3 to be compared. Each thermometer 3 to be compared has a corresponding resistance-temperature curve. Based on the resistance-temperature curve and its respective resistance value, the temperature value detected by each thermometer 3 to be calibrated can be obtained.

[0106] Second, the temperature values ​​detected by all thermometers 3 are weighted and averaged to obtain the weighted average temperature value.

[0107] Specifically, since each thermometer 3 needs to measure a corresponding time period, the average value within the measurement time period can be taken as the temperature value measured by thermometer 3, and then the weighted average temperature value of all thermometer 3 temperature values ​​can be obtained based on the uncertainty weighting.

[0108] Third, calculate the deviation between the temperature value detected by each thermometer 3 and the weighted average temperature value.

[0109] Specifically, by comparing the temperature value of each thermometer 3 to be calibrated with the weighted average temperature value, the equivalence of the temperature values ​​between each thermometer 3's reading and the weighted average temperature value can be obtained. This allows the readings of each thermometer 3 to be converted to the standard of the weighted average temperature value, which is beneficial for reaching a consensus temperature and laying the foundation for the formation of international temperature standards. In addition, a reference thermometer can also be set up in this embodiment. This reference thermometer continuously measures the fluctuations in ambient temperature during the measurement process to correct for measurement errors introduced by ambient temperature fluctuations in real time, thus providing accuracy in the comparison.

[0110] In some embodiments provided by this invention, the thermometer 3 is calibrated based on its resistance value, including:

[0111] First, at least one thermometer 3 is used as a reference thermometer, and the reference temperature value detected by the reference thermometer is obtained based on the resistance value of the reference thermometer.

[0112] Specifically, the number of reference thermometers is set to at least two. These at least two reference thermometers are connected to a resistance detection device 6 via a gating device 7, or the at least two reference thermometers are each connected to a different resistance detection device 6. Each reference thermometer has a defined resistance-temperature curve. Based on the resistance-temperature curve and the resistance value of the reference thermometer, the reference temperature value detected by the reference thermometer can be obtained. Then, the weighted average temperature value of the multiple reference thermometers is used as the reference temperature value.

[0113] Second, the resistance values ​​of the remaining thermometers 3 are fitted with the reference temperature values ​​to obtain the corresponding resistance-temperature curves of the remaining thermometers 3.

[0114] Specifically, the resistance values ​​of the remaining thermometers 3 are fitted to the reference temperature value to obtain the corresponding resistance-temperature curves of the remaining thermometers 3, i.e., the resistance-temperature R0-T characteristic curves. This allows the temperature data from the reference thermometer to be transferred to the remaining thermometers 3. Optionally, when fitting the resistance values ​​of the thermometers 3 to the reference temperature value, a (normalized) polynomial, a (normalized) logarithmic function, or a Chebyshev interpolation function can be used for fitting.

[0115] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A measurement system suitable for comparison and calibration, characterized in that, include: The chamber (1) is enclosed; A heat-conducting block (2) is disposed in the chamber (1), and the heat-conducting block (2) is provided with mounting holes for mounting a thermometer (3); Pressure control device (4), which is connected to the chamber (1) and is used to adjust the pressure inside the chamber (1); A refrigeration device (5) is connected to the chamber (1) and is used to cool the chamber (1); A resistance detection device (6) is provided, wherein at least two resistance detection devices (6) are provided, and the resistance detection devices (6) are used to detect the resistance value of the corresponding thermometer (3); The pressure control device (4) includes a vacuum pumping device and a gas source. Both the vacuum pumping device and the gas source are connected to the chamber (1). The vacuum pumping device is used to pump the gas in the chamber (1), and the gas source is used to introduce low-temperature working gas into the chamber (1). The thermometer (3) is placed into the mounting hole of the heat-conducting block (2), and the chamber (1) is cooled by the cooling device (5); Apply excitation current for at least three time periods to the thermometer (3), wherein the excitation current of the first time period and the excitation current of the last time period are equal, and the excitation current of the first time period and the excitation current of the last time period are both less than the excitation current of the middle time period. Detect the corresponding resistance value of the thermometer (3) in each time period through the resistance detection device (6). The thermometer (3) is calibrated or compared based on its resistance value; At least three time periods of excitation current are applied to each thermometer (3) in sequence. During the process of applying excitation current to any two thermometers (3) in sequence, when the excitation current applied to the previous thermometer (3) is in the middle time period, the excitation current applied to the next thermometer (3) is in the first time period, and the middle time periods of the excitation current applied to the two thermometers (3) are staggered.

2. The measurement system suitable for comparison and calibration according to claim 1, characterized in that, It also includes a gating device (7), at least some of the resistance detection devices (6) are connected to the corresponding thermometers (3) through the corresponding gating device (7), and at least one of the resistance detection devices (6) is connected to at least two thermometers (3) through the corresponding gating device (7), wherein the gating device (7) is configured to selectively connect any one thermometer (3) to the resistance detection device (6), or disconnect all thermometers (3) from the resistance detection device (6).

3. The measurement system suitable for comparison and calibration according to claim 1, characterized in that, It also includes a connector. The chamber (1) includes a cylinder (101) and a flange (102). The cylinder (101) has an opening. The flange (102) is connected to the cylinder (101) and closes the opening. The connector is made of heat-insulating material and connects the cylinder (101) and the heat-conducting block (2).

4. The measurement system suitable for comparison and calibration according to claim 1, characterized in that, It also includes a vacuum plug (8), which is located in the chamber (1). The resistance detection device (6) is located outside the chamber (1). The lead of the resistance detection device (6) extends into the chamber (1) through the vacuum plug (8) and is connected to the corresponding thermometer (3).

5. A measurement method, characterized in that, Based on the measurement system suitable for comparison and calibration as described in any one of claims 1-4, the thermometer (3) is compared based on the resistance value, including: At least one thermometer (3) is used as a reference thermometer, and the reference temperature value detected by the reference thermometer is obtained based on the resistance value of the reference thermometer. Based on the resistance values ​​of the other thermometers (3), the temperature value detected by each thermometer (3) is obtained; Calculate the deviation between the temperature value detected by the remaining thermometers (3) and the reference temperature value.

6. A measurement method, characterized in that, Based on the measurement system suitable for comparison and calibration as described in any one of claims 1-4, the thermometer (3) is compared based on the resistance value, including: Based on the resistance value of each thermometer (3), the temperature value detected by each thermometer (3) is obtained; The temperature values ​​detected by all thermometers (3) are weighted and averaged to obtain the weighted average temperature value; Calculate the deviation between the temperature value detected by each thermometer (3) and the weighted average temperature value.

7. A measurement method, characterized in that, Based on the measurement system suitable for comparison and calibration as described in any one of claims 1-4, the thermometer (3) is calibrated based on the resistance value, including: At least one thermometer (3) is used as a reference thermometer, and the reference temperature value detected by the reference thermometer is obtained based on the resistance value of the reference thermometer. The resistance values ​​of the remaining thermometers (3) are fitted with the reference temperature values ​​to obtain the corresponding resistance-temperature curves of the remaining thermometers (3).

Images