Temperature calibration method, system, computer and medium for thermal resistance temperature sensor

Abstract

The present invention discloses a temperature calibration method for a thermal resistor temperature sensor, comprising: constructing an initial temperature calibration curve model; adjusting the resistance value of an adjustable resistance box to the resistance value corresponding to the thermal resistor temperature sensor to be calibrated at a first preset temperature and a second preset temperature, respectively, and measuring a first voltage signal and a second voltage signal at both ends of the adjustable resistance box; calculating a first calibration temperature based on the first voltage signal, and calculating a second calibration temperature based on the second voltage signal; inputting the first calibration temperature into the temperature calibration curve model, calculating a first temperature correction parameter of the temperature calibration curve model, and thereby obtaining a first temperature calibration curve model; inputting the second calibration temperature into the first temperature calibration curve model, and calculating a second temperature correction parameter of the temperature calibration curve model. The present invention can solve the error problem existing in existing two-wire temperature measurement methods and improve the accuracy of temperature measurement.

Description

Technical Field

[0001] The present invention relates to the field of temperature measurement, and in particular to a temperature calibration method, system, computer and medium for a thermal resistance temperature sensor. Background Art

[0002] Common two-wire temperature measurement methods include the bridge method, constant current source method, and capacitor-resistance charge-discharge method. These methods typically use a "standard resistor" with a known resistance value. In the bridge and constant current source methods, a microcontroller calculates the resistance of the RTD under test based on the voltage divider relationship between the RTD under test and the standard resistor in the circuit, as well as the resistance value of the standard resistor. In the capacitor-resistance charge-discharge method, the microcontroller controls the RTD under test and the standard resistor to charge and discharge a capacitor, respectively. The resistance of the RTD under test is calculated based on the RC charge and discharge times and the standard resistor value.

[0003] However, the two-wire temperature measurement method may cause inaccurate temperature measurement due to circuit errors, reference standard resistor errors, or temperature sensor interface errors. Summary of the Invention

[0004] The technical problem to be solved by the present invention is to provide a temperature calibration method, system, computer and medium for a thermal resistor temperature sensor, which can solve the error problem existing in the existing two-wire temperature measurement method and improve the accuracy of temperature measurement.

[0005] In order to solve the above technical problems, the present invention provides a temperature calibration method for a thermal resistor temperature sensor, comprising: constructing an initial temperature calibration curve model; adjusting the resistance value of an adjustable resistance box to the resistance value corresponding to the thermal resistor temperature sensor to be calibrated at a first preset temperature and a second preset temperature, and measuring a first voltage signal and a second voltage signal at both ends of the adjustable resistance box, respectively; calculating a first calibration temperature based on the first voltage signal, and calculating a second calibration temperature based on the second voltage signal; inputting the first calibration temperature into the temperature calibration curve model, calculating a first temperature correction parameter of the temperature calibration curve model, and thereby obtaining a first temperature calibration curve model; inputting the second calibration temperature into the first temperature calibration curve model, calculating a second temperature correction parameter of the temperature calibration curve model, and thereby obtaining a second temperature calibration curve model; wherein, one end of the adjustable resistance box is electrically connected to a constant current source, and the other end of the adjustable resistance box is grounded through a standard resistor of known resistance, and the first preset temperature is lower than the second preset temperature.

[0006] Preferably, the temperature calibration method of the thermistor temperature sensor also includes: selecting at least three verification temperatures in the temperature range from the first preset temperature to the second preset temperature; adjusting the resistance value of the adjustable resistance box to the resistance value corresponding to the thermistor temperature sensor to be calibrated at each verification temperature, and measuring the verification voltage signals at both ends of the adjustable resistance box respectively; calculating the calibration verification temperature according to the verification voltage signal; inputting each of the calibration verification temperatures into the second temperature calibration curve model respectively to calculate the calibration output temperature; calculating the temperature error according to each of the calibration output temperatures and the corresponding verification temperature; judging whether each of the temperature errors meets the preset error temperature range; if the judgment is yes, the temperature calibration is completed; if the judgment is no, the temperature calibration needs to be re-performed.

[0007] Preferably, the step of calculating the temperature error based on each of the calibration output temperatures and the corresponding verification temperature includes: calculating the temperature difference between each of the calibration output temperatures and the corresponding verification temperature; calculating the ratio of each of the differences to the corresponding calibration output temperature; and calculating the temperature error based on each of the ratios.

[0008] Preferably, the initial temperature calibration curve model is: t=k(T+b), wherein t is the temperature value after temperature calibration, k is the second temperature correction parameter, b is the first temperature correction parameter, and T is the first calibration temperature or the second calibration temperature.

[0009] Preferably, before temperature calibration, the value of k is 1 and the value of b is 0.

[0010] Preferably, the steps of calculating the first calibration temperature according to the first voltage signal and calculating the second calibration temperature according to the second voltage signal include: respectively calculating the first resistance value and the second resistance value of the adjustable resistance box according to the first voltage signal and the second voltage signal; and calculating the first calibration temperature and the second calibration temperature by a table lookup method or a formula method according to the first resistance value and the second resistance value.

[0011] The present invention also provides a temperature calibration system for a thermal resistor temperature sensor, which is used to implement any of the above-mentioned temperature calibration methods for the thermal resistor temperature sensor, including a model construction module, a voltage detection module, a first calculation module, a second calculation module, an adjustable resistance box, a constant current source and a standard resistor, one end of the adjustable resistance box is electrically connected to the constant current source, and the other end of the adjustable resistance box is grounded through a standard resistor of a known resistance value; the model construction module is used to construct an initial temperature calibration curve model; the voltage detection module is used to respectively measure the first voltage signal and the second voltage signal at both ends of the adjustable resistance box; the first calculation module is used to calculate the first calibration temperature according to the first voltage signal and the second calibration temperature according to the second voltage signal The second calculation module is used to input the first calibration temperature into the temperature calibration curve model, calculate the first temperature correction parameter of the temperature calibration curve model, and then obtain the first temperature calibration curve model, and is used to input the second calibration temperature into the first temperature calibration curve model, calculate the second temperature correction parameter of the temperature calibration curve model, and then obtain the second temperature calibration curve model; wherein the resistance value of the adjustable resistance box is adjusted to the resistance value corresponding to the first preset temperature and the second preset temperature of the thermal resistance temperature sensor to be calibrated, and the first voltage signal and the second voltage signal at both ends of the adjustable resistance box are measured respectively, and the first preset temperature is less than the second preset temperature.

[0012] Preferably, the temperature calibration system of the thermistor temperature sensor also includes a verification module, which includes: a temperature selection unit, used to select at least three verification temperatures in the temperature range from the first preset temperature to the second preset temperature; a first calculation unit, used to calculate the calibration verification temperature according to the verification voltage signal; a second calculation unit, used to input each of the calibration verification temperatures into the second temperature calibration curve model respectively, and calculate the calibration output temperature; a third calculation unit, used to calculate the temperature error according to each of the calibration output temperatures and the corresponding verification temperature; a judgment unit, used to judge whether each of the temperature errors meets the preset error temperature range, if it is judged to be yes, the temperature calibration is completed, if it is judged to be no, the temperature calibration needs to be re-performed; wherein, the resistance value of the adjustable resistance box is adjusted to the resistance value corresponding to each of the verification temperatures of the thermistor temperature sensor to be calibrated, and the verification voltage signals at both ends of the adjustable resistance box are measured respectively.

[0013] The present invention also provides a computer device, comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor implements the steps of any of the above methods when executing the computer program.

[0014] The present invention also provides a computer-readable storage medium having a computer program stored thereon, wherein the computer program implements the steps of any of the above methods when executed by a processor.

[0015] The beneficial effects of implementing the present invention are:

[0016] The present invention provides a temperature calibration method, system, computer device, and readable storage medium for a thermal resistor temperature sensor. The method constructs an initial temperature calibration curve model, adjusts the resistance value of an adjustable resistance box to the resistance value corresponding to a first preset temperature and a second preset temperature of the thermal resistor temperature sensor to be calibrated, and measures a first voltage signal and a second voltage signal at both ends of the adjustable resistance box. The method then calculates a first calibration temperature based on the first voltage signal and a second calibration temperature based on the second voltage signal. The method then inputs the first calibration temperature into the temperature calibration curve model, calculates a first temperature correction parameter for the temperature calibration curve model, and obtains a first temperature calibration curve model. The method then inputs the second calibration temperature into the first temperature calibration curve model, calculates a second temperature correction parameter for the temperature calibration curve model, and obtains a second temperature calibration curve model. The method solves the error problem existing in existing two-wire temperature measurement methods and improves the accuracy of temperature measurement. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 This is a flow chart of the temperature calibration method of the thermal resistance temperature sensor provided by the present invention;

[0018] Figure 2 This is a schematic diagram of the electrical connection principle provided by the present invention;

[0019] Figure 3 It is a flow chart of the verification method provided by the present invention;

[0020] Figure 4 is a flow chart of the error calculation method provided by the present invention;

[0021] Figure 5 This is a flow chart of the calibration temperature calculation method provided by the present invention;

[0022] Figure 6 Schematic diagram of a temperature calibration system for a thermal resistance temperature sensor provided by the present invention;

[0023] Figure 7 It is a schematic diagram of the verification module provided by the present invention. DETAILED DESCRIPTION

[0024] To make the objectives, technical solutions, and advantages of the present invention more apparent, the present invention will be further described in detail below with reference to the accompanying drawings. It is hereby stated that any directional terms such as "up," "down," "left," "right," "front," "back," "inside," and "outside" that appear or will appear herein are based solely on the accompanying drawings and are not intended to limit the present invention.

[0025] like Figure 1 As shown, the present invention provides a temperature calibration method for a thermal resistance temperature sensor, comprising:

[0026] S101, constructing an initial temperature calibration curve model;

[0027] S102, adjusting the resistance value of the adjustable resistance box to the resistance value corresponding to the first preset temperature and the second preset temperature of the thermal resistance temperature sensor to be calibrated, and measuring the first voltage signal and the second voltage signal at both ends of the adjustable resistance box respectively;

[0028] S103, calculating a first calibration temperature according to the first voltage signal, and calculating a second calibration temperature according to the second voltage signal;

[0029] S104, inputting the first calibration temperature into the temperature calibration curve model, calculating a first temperature correction parameter of the temperature calibration curve model, and thereby obtaining a first temperature calibration curve model;

[0030] S105, inputting the second calibration temperature into the first temperature calibration curve model, calculating a second temperature correction parameter of the temperature calibration curve model, and thereby obtaining a second temperature calibration curve model;

[0031] One end of the adjustable resistance box is electrically connected to a constant current source, the other end of the adjustable resistance box is grounded via a standard resistor of known resistance, and the first preset temperature is lower than the second preset temperature.

[0032] The present invention relates to the fields of thermal resistance temperature sensor measurement, temperature calibration, and microcontrollers. Specifically, it relates to a temperature calibration and verification method for a two-wire temperature sensor. Because commonly used two-wire temperature measurement methods inevitably contain circuit errors, standard resistor errors, and temperature sensor interface errors, it is necessary to calibrate the temperature measurement interface to ensure accurate temperature measurement.

[0033] The present invention constructs an initial temperature calibration curve model, adjusts the resistance value of the adjustable resistance box to the resistance value corresponding to the first preset temperature and the second preset temperature of the thermal resistance temperature sensor to be calibrated, and respectively measures the first voltage signal and the second voltage signal at both ends of the adjustable resistance box. The first calibration temperature is calculated based on the first voltage signal, and the second calibration temperature is calculated based on the second voltage signal. The first calibration temperature is then input into the temperature calibration curve model to calculate the first temperature correction parameter of the temperature calibration curve model, thereby obtaining the first temperature calibration curve model. The second calibration temperature is then input into the first temperature calibration curve model to calculate the second temperature correction parameter of the temperature calibration curve model, thereby obtaining the second temperature calibration curve model. The present invention can solve the error problem existing in existing two-wire temperature measurement methods and improve the accuracy of temperature measurement.

[0034] Common two-wire temperature measurement methods include the bridge method, constant current source method, and capacitor-resistance charge-discharge method. These methods typically use a "standard resistor" with a known resistance value. In the bridge and constant current source methods, a microcontroller calculates the resistance of the RTD under test based on the voltage divider relationship between the RTD under test and the standard resistor in the circuit, as well as the resistance value of the standard resistor. In the capacitor-resistance charge-discharge method, the microcontroller controls the RTD under test and the standard resistor to charge and discharge into a capacitor, calculating the resistance of the RTD under test based on the RC charge and discharge times and the standard resistor value.

[0035] like Figure 2 This is a simplified diagram of a temperature measurement circuit. Terminals A and B connect to the two core wires of a thermistor temperature sensor. In actual applications, they connect to a PT1000 or PT100 temperature sensor. Because two-wire temperature measurement inevitably involves circuit errors, reference resistor errors, and temperature sensor interface errors, calibration of the temperature measurement interface is necessary. This article describes a method that uses a high-precision standard resistor box to simulate a PT1000 or PT100 temperature sensor to calibrate and correct the A and B terminals, resulting in more accurate temperature measurements.

[0036] like Figure 3 As shown, the temperature calibration method of the thermal resistance temperature sensor also includes:

[0037] S201, selecting at least three verification temperatures in the temperature range from the first preset temperature to the second preset temperature;

[0038] S202, adjusting the resistance value of the adjustable resistance box to the resistance value corresponding to each of the verification temperatures of the thermal resistance temperature sensor to be calibrated, and measuring the verification voltage signals at both ends of the adjustable resistance box respectively;

[0039] S203, calculating a calibration verification temperature according to the verification voltage signal;

[0040] S204, inputting each of the calibration verification temperatures into the second temperature calibration curve model to calculate a calibration output temperature;

[0041] S205, calculating a temperature error based on each of the calibration output temperatures and the corresponding verification temperature;

[0042] S206, determining whether each of the temperature errors satisfies a preset error temperature range;

[0043] S207, when the judgment is yes, the temperature calibration is completed;

[0044] S208: If the judgment is yes or no, the temperature calibration needs to be re-performed.

[0045] It should be noted that in this embodiment, at least three verification temperatures are selected in the temperature range from the first preset temperature to the second preset temperature; the resistance value of the adjustable resistance box is adjusted to the resistance value corresponding to each verification temperature of the thermal resistance temperature sensor to be calibrated, and the verification voltage signals at both ends of the adjustable resistance box are measured respectively; and the calibration verification temperature is calculated based on the verification voltage signal; each of the calibration verification temperatures is input into the second temperature calibration curve model respectively to calculate the calibration output temperature; the temperature error is calculated based on each calibration output temperature and the corresponding verification temperature; it is determined whether each temperature error meets the preset error temperature range; if the determination is yes, the temperature calibration is completed; if the determination is no, the temperature calibration needs to be repeated. By adopting this embodiment, the temperature calibration method provided by the present invention can be error verified, further improving the accuracy of temperature measurement.

[0046] like Figure 4 As shown, the step of calculating the temperature error according to each calibration output temperature and the corresponding verification temperature includes:

[0047] S301, calculating the temperature difference between each calibration output temperature and the corresponding verification temperature;

[0048] S302, calculating the ratio of each difference to the corresponding calibration output temperature;

[0049] S303: Calculate the temperature error according to each ratio.

[0050] It should be noted that, in this embodiment, the temperature difference between each calibration output temperature and the corresponding verification temperature is calculated, and the ratio of each difference to the corresponding calibration output temperature is calculated; finally, the temperature error is calculated according to each ratio.

[0051] Preferably, the initial temperature calibration curve model is: t = k(T + b), where t is the temperature value after temperature calibration, k is the second temperature correction parameter, b is the first temperature correction parameter, and T is the first calibration temperature or the second calibration temperature. Furthermore, before temperature calibration, the value of k is 1 and the value of b is 0.

[0052] It should be noted that in this embodiment, the microcontroller has a pre-set temperature calibration curve t = k(T + b). Where: t is the temperature value after temperature calibration; k is the curve parameter after calibration, and the default value before calibration is k = 1; b is the curve parameter after calibration, and the default value before calibration is b = 0; T is the temperature value calculated based on the corresponding curve formula between temperature and resistance. T = 0.00001 * R 2 +0.2359*R-245.9.

[0053] like Figure 5 As shown, the step of calculating the first calibration temperature according to the first voltage signal and calculating the second calibration temperature according to the second voltage signal includes:

[0054] S401, calculating a first resistance value and a second resistance value of an adjustable resistance box according to the first voltage signal and the second voltage signal respectively;

[0055] S402 , calculating a first calibration temperature and a second calibration temperature according to the first resistance value and the second resistance value by using a table lookup method or a formula method.

[0056] It should be noted that, in this embodiment, in the above temperature measurement method, the microcontroller measures the resistance of the thermal resistor to be measured. There are generally two methods to obtain the corresponding temperature value based on the resistance of the thermal resistor:

[0057] The first method is the table lookup method. A data table of the thermal resistor resistance and temperature is first saved in the microcontroller's memory. During measurement, the corresponding temperature value is obtained by looking up the table according to the measured thermal resistor resistance value. This method requires a large amount of storage space.

[0058] The second method is the formula calculation method. For example, in PT1000 temperature measurement, the formula T = 0.00001*R 2 The temperature is calculated by adding 0.2359*R-245.9.

[0059] like Figure 6As shown, the present invention also provides a temperature calibration system 100 for a thermal resistor temperature sensor, which is used to implement any of the above-mentioned temperature calibration methods for the thermal resistor temperature sensor, including a model construction module 1, a voltage detection module 2, a first calculation module 3, a second calculation module 4, an adjustable resistance box 5, a constant current source 6 and a standard resistor 7, one end of the adjustable resistance box 5 is electrically connected to the constant current source 6, and the other end of the adjustable resistance box 5 is grounded through a standard resistor 7 with a known resistance value; the model construction module 1 is used to construct an initial temperature calibration curve model; the voltage detection module 2 is used to respectively measure the first voltage signal and the second voltage signal at both ends of the adjustable resistance box 5; the first calculation module 3 is used to calculate the first calibration temperature according to the first voltage signal And calculate the second calibration temperature according to the second voltage signal; the second calculation module 4 is used to input the first calibration temperature into the temperature calibration curve model, calculate the first temperature correction parameter of the temperature calibration curve model, and then obtain the first temperature calibration curve model, and is used to input the second calibration temperature into the first temperature calibration curve model, calculate the second temperature correction parameter of the temperature calibration curve model, and then obtain the second temperature calibration curve model; wherein, the resistance value of the adjustable resistance box 5 is adjusted to the resistance value corresponding to the first preset temperature and the second preset temperature of the thermal resistance temperature sensor to be calibrated, and the first voltage signal and the second voltage signal at both ends of the adjustable resistance box 5 are measured respectively, and the first preset temperature is less than the second preset temperature.

[0060] The present invention relates to the fields of thermal resistance temperature sensor measurement, temperature calibration, and microcontrollers. Specifically, it relates to a temperature calibration and verification method for a two-wire temperature sensor. Because commonly used two-wire temperature measurement methods inevitably contain circuit errors, standard resistor errors, and temperature sensor interface errors, it is necessary to calibrate the temperature measurement interface to ensure accurate temperature measurement.

[0061] The present invention constructs an initial temperature calibration curve model through the model construction module 1; measures the first voltage signal and the second voltage signal at both ends of the adjustable resistance box 5 respectively through the voltage detection module 2; calculates the first calibration temperature based on the first voltage signal and the second calibration temperature based on the second voltage signal through the first calculation module 3; inputs the first calibration temperature into the temperature calibration curve model through the second calculation module 4, calculates the first temperature correction parameter of the temperature calibration curve model, and then obtains the first temperature calibration curve model; and inputs the second calibration temperature into the first temperature calibration curve model, calculates the second temperature correction parameter of the temperature calibration curve model, and then obtains the second temperature calibration curve model. The present invention can solve the error problem existing in the existing two-wire temperature measurement method and improve the accuracy of temperature measurement.

[0062] Common two-wire temperature measurement methods include the bridge method, constant current source method, and capacitor-resistance charge-discharge method. These methods typically use a "standard resistor" with a known resistance value. In the bridge and constant current source methods, a microcontroller calculates the resistance of the RTD under test based on the voltage divider relationship between the RTD under test and the standard resistor in the circuit, as well as the resistance value of the standard resistor. In the capacitor-resistance charge-discharge method, the microcontroller controls the RTD under test and the standard resistor to charge and discharge into a capacitor, calculating the resistance of the RTD under test based on the RC charge and discharge times and the standard resistor value.

[0063] like Figure 2 This is a simplified diagram of a temperature measurement circuit. Terminals A and B connect to the two core wires of a thermistor temperature sensor. In actual applications, they connect to a PT1000 or PT100 temperature sensor. Because two-wire temperature measurement inevitably involves circuit errors, reference resistor errors, and temperature sensor interface errors, calibration of the temperature measurement interface is necessary. This article describes a method that uses a high-precision standard resistor box to simulate a PT1000 or PT100 temperature sensor to calibrate and correct the A and B terminals, resulting in more accurate temperature measurements.

[0064] like Figure 7 As shown, the temperature calibration system 100 of the thermal resistor temperature sensor also includes a verification module 8, which includes: a temperature selection unit 81, which is used to select at least three verification temperatures in the temperature range from the first preset temperature to the second preset temperature; a first calculation unit 82, which is used to calculate the calibration verification temperature according to the verification voltage signal; a second calculation unit 83, which is used to input each of the calibration verification temperatures into the second temperature calibration curve model to calculate the calibration output temperature; a third calculation unit 84, which is used to calculate the temperature error according to each of the calibration output temperatures and the corresponding verification temperature; a judgment unit 85, which is used to judge whether each of the temperature errors meets the preset error temperature range. If the judgment is yes, the temperature calibration is completed. If the judgment is no, the temperature calibration needs to be re-performed; wherein, the resistance value of the adjustable resistance box is adjusted to the resistance value corresponding to the thermal resistor temperature sensor to be calibrated at each of the verification temperatures, and the verification voltage signals at both ends of the adjustable resistance box are measured respectively.

[0065] It should be noted that, in this embodiment, the temperature selection unit 81 selects at least three verification temperatures in the temperature range from the first preset temperature to the second preset temperature; the first calculation unit 82 calculates the calibration verification temperature based on the verification voltage signal; the second calculation unit 83 inputs each of the calibration verification temperatures into the second temperature calibration curve model to calculate the calibration output temperature; the third calculation unit 84 calculates the temperature error based on each of the calibration output temperatures and the corresponding verification temperature; the judgment unit 85 judges whether each of the temperature errors meets the preset error temperature range. If the judgment is yes, the temperature calibration is completed; if the judgment is no, the temperature calibration needs to be repeated. By adopting this embodiment, the temperature calibration method provided by the present invention can be error verified, further improving the accuracy of temperature measurement.

[0066] The present invention also provides a computer device, comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor implements the steps of any of the above methods when executing the computer program.

[0067] The present invention also provides a computer-readable storage medium having a computer program stored thereon, wherein the computer program implements the steps of any of the above methods when executed by a processor.

[0068] In summary, the embodiments of the present invention specifically include:

[0069] (1) Prepare a high-precision standard resistance box with adjustable resistance, and connect the two terminals of the resistance box to Figure 1 The A and B terminals are shown. This adjustable, high-precision standard resistance box can simulate the resistance range of actual temperature sensors. During calibration, first calibrate the temperature curve parameter b, then the parameter k.

[0070] (2) First, adjust the resistance value of the adjustable high-precision standard resistance box to the resistance value corresponding to the temperature sensor at 0°C. For example, the resistance value corresponding to 0.00°C of the PT1000 temperature sensor is 1000Ω. When calibrating the PT1000 temperature sensor, this step adjusts the standard resistance box to 1000Ω.

[0071] The microcontroller calculates the corresponding temperature value T based on the temperature measurement method and the aforementioned temperature-resistance correspondence formula. After the microcontroller detects that the resistance value of the standard resistance box is stable, the temperature corresponding to the actual resistance of the standard resistance box is 0.00°C. The temperature value actually measured by the microcontroller is t0°C, so the error correction curve parameter b of the temperature calibration curve at this time is calculated as 0.00°C - t0°C.

[0072] (3) Adjust the resistance value of the adjustable high-precision standard resistance box to the resistance value corresponding to the temperature sensor at 100°C. For example, the resistance value corresponding to 100°C of the PT1000 temperature sensor is 1385.06Ω. When calibrating the PT1000 temperature sensor, adjust the standard resistance box to 1385.06Ω in this step.

[0073] The microcontroller calculates the corresponding temperature value T based on the temperature measurement method and the corresponding formula between temperature and resistance mentioned above, and then calculates t100 based on the formula t=k(T+b) and the parameter b calibrated in the previous step. After the microcontroller detects that the resistance value of the standard resistance box is stable, the temperature corresponding to the actual resistance of the standard resistance box is 100.00℃. The temperature value actually measured by the microcontroller is t100℃, so the parameter k=100.00 / t100 of the error correction curve of the temperature calibration curve at this time is calculated.

[0074] (4) After the calibration in the above steps, the parameters of the formula t=k(T+b) have been determined, and the microcontroller saves the parameters of k and b. The temperature calibration method eliminates the error in the measurement and improves the accuracy of the temperature interface measurement system.

[0075] (5) After calibration through the above steps, we select three temperature points within the range of 0-100.00℃ for verification. This is to verify that the calibration parameters are correct after calibration. After long-term research, we selected 3.00℃, 38.00℃, and 78.00℃ to meet the temperature accuracy verification in the low, medium, and high temperature zones. If one of the three does not meet the accuracy requirements, recalibration is required. Adjust the resistance value of the adjustable high-precision standard resistor box to the resistance value corresponding to the above temperature, and compare the actual temperature value measured by the microcontroller with the above theory to obtain the single temperature error E1. If the temperature difference of the two paired temperature sensors is verified at the same time, the microprocessor will simultaneously calculate the temperature difference error E2 of the two temperature sensors. If the E1 and E2 errors of the three locations meet the product requirements, the verification is passed, otherwise the temperature calibration needs to be re-performed.

[0076] The above is a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principles of the present invention. These improvements and modifications are also considered to be within the scope of protection of the present invention.

Claims

1. A temperature calibration method for a thermal resistance temperature sensor, characterized in that: include: Constructing an initial temperature calibration curve model; Adjusting the resistance value of the adjustable resistance box to the resistance value corresponding to the first preset temperature and the second preset temperature of the thermal resistance temperature sensor to be calibrated, and measuring the first voltage signal and the second voltage signal at both ends of the adjustable resistance box respectively; Calculate a first calibration temperature according to the first voltage signal, and calculate a second calibration temperature according to the second voltage signal; Inputting the first calibration temperature into the temperature calibration curve model, calculating a first temperature correction parameter of the temperature calibration curve model, and thereby obtaining a first temperature calibration curve model; Inputting the second calibration temperature into the first temperature calibration curve model, calculating a second temperature correction parameter of the temperature calibration curve model, and thereby obtaining a second temperature calibration curve model; One end of the adjustable resistance box is electrically connected to a constant current source, the other end of the adjustable resistance box is grounded via a standard resistor of known resistance, and the first preset temperature is lower than the second preset temperature.

2. The temperature calibration method of the thermal resistance temperature sensor according to claim 1, characterized in that: Also includes: Select at least three verification temperatures in the temperature range from the first preset temperature to the second preset temperature; Adjusting the resistance value of the adjustable resistance box to the resistance value corresponding to each of the verification temperatures of the thermal resistance temperature sensor to be calibrated, and measuring the verification voltage signals at both ends of the adjustable resistance box respectively; calculating a calibration verification temperature based on the verification voltage signal; inputting each of the calibration verification temperatures into the second temperature calibration curve model to calculate a calibration output temperature; Calculating a temperature error based on each of the calibration output temperatures and the corresponding verification temperature; Determining whether each of the temperature errors satisfies a preset error temperature range; If the judgment is yes, the temperature calibration is completed; If the answer is yes, the temperature needs to be recalibrated.

3. The temperature calibration method of the thermal resistance temperature sensor according to claim 2, characterized in that: The step of calculating the temperature error according to each of the calibration output temperatures and the corresponding verification temperature comprises: Calculating the temperature difference between each of the calibration output temperatures and the corresponding verification temperature; Calculating a ratio of each of the difference values ​​to the corresponding calibration output temperature; A temperature error is calculated based on each of the ratios.

4. The temperature calibration method of the thermal resistance temperature sensor according to claim 1, wherein: The initial temperature calibration curve model is: t=k(T+b), where, t is the temperature value after temperature calibration, k is the second temperature correction parameter, b is the first temperature correction parameter, and T is the first calibration temperature or the second calibration temperature.

5. The temperature calibration method of the thermal resistance temperature sensor according to claim 4, characterized in that: Before temperature calibration, the value of k is 1 and the value of b is 0.

6. The temperature calibration method of the thermal resistance temperature sensor according to claim 1, characterized in that: The step of calculating the first calibration temperature according to the first voltage signal and calculating the second calibration temperature according to the second voltage signal comprises: Calculating a first resistance value and a second resistance value of the adjustable resistance box according to the first voltage signal and the second voltage signal respectively; The first calibration temperature and the second calibration temperature are calculated according to the first resistance value and the second resistance value by using a table lookup method or a formula method.

7. A temperature calibration system for a thermal resistance temperature sensor, characterized in that: A temperature calibration method for a thermal resistance temperature sensor according to any one of claims 1 to 6, comprising a model building module, a voltage detection module, a first calculation module, a second calculation module, an adjustable resistance box, a constant current source, and a standard resistor, wherein one end of the adjustable resistance box is electrically connected to the constant current source, and the other end of the adjustable resistance box is grounded via a standard resistor of known resistance; The model building module is used to build an initial temperature calibration curve model; The voltage detection module is used to measure a first voltage signal and a second voltage signal at both ends of the adjustable resistance box respectively; The first calculation module is used to calculate a first calibration temperature according to the first voltage signal and to calculate a second calibration temperature according to the second voltage signal; The second calculation module is used to input the first calibration temperature into the temperature calibration curve model, calculate the first temperature correction parameter of the temperature calibration curve model, and thereby obtain the first temperature calibration curve model; and is used to input the second calibration temperature into the first temperature calibration curve model, calculate the second temperature correction parameter of the temperature calibration curve model, and thereby obtain the second temperature calibration curve model; Among them, the resistance value of the adjustable resistance box is adjusted to the resistance value corresponding to the first preset temperature and the second preset temperature of the thermal resistance temperature sensor to be calibrated, and the first voltage signal and the second voltage signal at both ends of the adjustable resistance box are measured respectively, and the first preset temperature is lower than the second preset temperature.

8. The temperature calibration system for a thermal resistance temperature sensor according to claim 7, wherein: Also included is a verification module, the verification module including: a temperature selection unit, configured to select at least three verification temperatures within a temperature range from the first preset temperature to the second preset temperature; wherein the resistance value of the adjustable resistance box is adjusted to the resistance value corresponding to the thermal resistance temperature sensor to be calibrated at each of the verification temperatures, and the verification voltage signals across the adjustable resistance box are measured respectively; a first calculation unit, configured to calculate a calibration verification temperature according to the verification voltage signal; a second calculation unit, configured to input each of the calibration verification temperatures into the second temperature calibration curve model to calculate a calibration output temperature; a third calculation unit, configured to calculate a temperature error according to each of the calibration output temperatures and the corresponding verification temperature; A judging unit, configured to judge whether each of the temperature errors satisfies a preset error temperature range, If the judgment is yes, the temperature calibration is completed. If the answer is yes, the temperature needs to be recalibrated.

9. A computer device comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein: When the processor executes the computer program, the steps of the method according to any one of claims 1 to 6 are implemented.

10. A computer-readable storage medium having a computer program stored thereon, characterized in that: When the computer program is executed by a processor, the steps of the method according to any one of claims 1 to 6 are implemented.

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