Temperature correction method and device based on infrared dot matrix temperature measurement sensor

Abstract

The invention discloses a temperature correction method and device based on an infrared dot matrix temperature measurement sensor. The method comprises the steps that the infrared dot matrix temperature measurement sensor is used for collecting a temperature distribution diagram of a to-be-measured area; acquiring the actual temperature of the geometric center of the to-be-measured area through a standard thermometer; obtaining the measurement temperature of each pixel according to the temperature distribution diagram; according to the actual temperature and the measured temperature of the geometric center of the to-be-measured area, a center pixel temperature correction coefficient is obtained through calculation; according to the position coordinates of the pixels in the temperature distribution diagram, a pixel position correction coefficient is obtained through calculation; calculating to obtain a pixel position nonlinear correction coefficient according to the nonlinear parameter obtained by pre-fitting and the position coordinate of the pixel; and according to the pixel position nonlinear correction coefficient, the center pixel temperature correction coefficient, the pixel position correction coefficient and the measured temperature of the pixel, calculating to obtain the correction temperature of the corresponding pixel. The method can improve the accuracy of infrared temperature measurement in the area.

Description

Technical Field

[0001] The present invention relates to the field of infrared temperature measurement technology, and in particular to a temperature correction method and device based on an infrared dot matrix temperature measurement sensor. Background Art

[0002] At present, smart substations have become the basic model of substation construction. The control cabinets used in the power industry integrate the power distribution, measurement, monitoring, protection, and control functions of power equipment such as circuit breakers, disconnectors, and fully enclosed switchgear (GIS) into one cabinet. Although the existing control cabinets save the floor space of the cabinets, they integrate a variety of power equipment, resulting in a lot of wiring terminals inside. During use, these wiring terminals will heat up due to aging, rust, moisture leakage, etc., and even cause fire. Therefore, it is very necessary to monitor the temperature of the wiring inside the control cabinet.

[0003] There are currently three methods for testing the internal wiring terminals of the control cabinet:

[0004] 1. Electric power personnel regularly use thermometers to conduct manual temperature measurement on site, and measure the temperature at locations where wiring terminals are concentrated or where temperature rises easily to avoid overheating or fire hazards. This method is highly safe and accurate in measurement, but since it requires manual measurement, there are the following problems: it can only monitor at regular intervals, not in real time, and is inefficient.

[0005] 2. Use an infrared spot thermometer to measure the temperature. Install an infrared spot thermometer inside the control cabinet to measure the temperature. This method can be used to install the infrared spot thermometer in places where the wiring terminals are densely packed or where the wiring terminals are prone to heat. Although this method can measure the temperature of high-risk locations inside the control cabinet, due to the very small measurement range of the spot thermometer, it can often only measure the temperature of a single point. If a large number of infrared spot thermometers are installed inside the control cabinet, a lot of space will be required, and the cost will be high.

[0006] 3. Use temperature sensors for measurement. For example, patent document CN104132732B discloses a temperature monitoring system and method for a substation control cabinet based on real-time acquisition of the cabinet temperature. The patent uses a temperature acquisition module set in the substation control cabinet to collect the temperature inside the substation control cabinet in real time and upload it to the monitoring system through the network. This method uses a temperature sensor for non-contact temperature measurement. Although it can measure the temperature inside the measurement and control cabinet, due to the large temperature difference between the temperature at the densely connected terminals and the temperature at the non-dense terminals, it is difficult to measure the actual temperature at the densely connected terminals by simply measuring the temperature in the air, and the measurement effect is poor.

[0007] The infrared dot matrix temperature sensor is composed of multiple infrared temperature measurement units distributed in an array, which can obtain the temperature distribution within the covered temperature field at one time. However, if the infrared dot matrix temperature sensor is to achieve the designed measurement accuracy, the object to be measured needs to fill its field of view. However, the surface area of ​​each terminal is much smaller than the field of view of the infrared dot matrix temperature sensor. At this time, the temperature measured by the infrared dot matrix temperature sensor is not the actual temperature of the terminal. Therefore, there will be a temperature deviation, resulting in inaccurate measurement and difficulty in ensuring the monitoring effect. Summary of the invention

[0008] The present invention provides a temperature correction method and device based on an infrared dot matrix temperature measuring sensor, which can improve the temperature measurement accuracy of the infrared dot matrix temperature measuring sensor and reduce the production cost.

[0009] A temperature correction method based on an infrared dot matrix temperature measuring sensor, comprising:

[0010] Use infrared dot matrix temperature sensor to collect the temperature distribution map of the area to be measured;

[0011] Obtaining the actual temperature at the geometric center of the area to be measured by a standard thermometer;

[0012] According to the temperature distribution map, obtaining the measured temperature of each pixel;

[0013] Obtaining a center pixel temperature correction coefficient according to the actual temperature at the geometric center of the area to be measured and the measured temperature at the geometric center of the area to be measured;

[0014] Obtaining a pixel position correction coefficient according to the position coordinates of the pixels in the temperature distribution map;

[0015] Obtaining a pixel position nonlinear correction coefficient according to the pre-fitted nonlinear parameters and the pixel position coordinates;

[0016] The correction temperature of the corresponding pixel is calculated based on the pixel position nonlinear correction coefficient, the central pixel temperature correction coefficient, the pixel position correction coefficient and the measured temperature of the pixel.

[0017] Furthermore, the infrared dot matrix temperature sensor includes m rows and n columns of infrared temperature sensing units, each infrared temperature sensing unit corresponds to a pixel in the temperature distribution map, wherein m and n are both greater than or equal to 2.

[0018] Furthermore, the central pixel temperature correction coefficient is a ratio of the actual temperature at the geometric center of the area to be measured to the measured temperature at the geometric center of the area to be measured.

[0019] Further, according to the position coordinates of the pixels in the temperature distribution map, a pixel position correction coefficient is calculated, including:

[0020] The geometric center of the area to be measured is set as the origin, the horizontal symmetry axis of the area to be measured is the X-axis, and the vertical symmetry axis is the Y-axis, to establish a field of view coordinate system;

[0021] Obtaining the maximum column viewing angle of the infrared dot matrix temperature measuring sensor, and calculating the distance from the infrared dot matrix temperature measuring sensor to the geometric center of the area to be measured according to the maximum X coordinate of the area to be measured and the maximum column viewing angle;

[0022] The distance from the infrared dot matrix temperature sensor to the geometric center of the area to be measured is taken as the Z coordinate, and the distance from the pixel to the infrared dot matrix temperature sensor is calculated according to the X coordinate value, the Y coordinate value and the Z coordinate of the pixel;

[0023] The ratio of the distance from the pixel to the infrared dot matrix temperature measuring sensor to the Z coordinate is used as the pixel position correction coefficient.

[0024] Furthermore, the nonlinear parameters are obtained by pre-fitting, including:

[0025] Cover the test area with the test field of view of the infrared dot matrix temperature sensor, and collect the test temperature distribution diagram of the test area;

[0026] Obtaining the actual test temperature at the geometric center of the test field of view by a standard thermometer;

[0027] Selecting a plurality of characteristic points on the test temperature distribution diagram, obtaining the test temperatures of the characteristic points, and obtaining the test temperature at the geometric center of the test field of view;

[0028] The geometric center of the test field of view is taken as the origin, the horizontal symmetry axis of the test field of view is taken as the X-axis, and the vertical symmetry axis is taken as the Y-axis, a test field of view coordinate system is established, and the pixel coordinates of the plurality of feature points are obtained;

[0029] Calculate and obtain a test center temperature correction coefficient based on the actual test temperature at the geometric center of the test field of view and the test temperature thereof;

[0030] According to the pixel coordinates of each feature point, the feature point position correction coefficient is calculated;

[0031] Calculate and obtain the rough correction temperature of the characteristic point according to the test center temperature correction coefficient, the characteristic point position correction coefficient and the test temperature of the characteristic point;

[0032] A coordinate system is established with the distance from the feature point to the geometric center of the test field of view as the horizontal coordinate and the temperature as the vertical coordinate;

[0033] Marking the feature point rough correction temperature and the test temperature of the feature point in the coordinate system and performing fitting to obtain an exponential function curve;

[0034] The base of the exponential function curve is calculated and obtained as the nonlinear parameter.

[0035] Furthermore, the rough correction temperature of the feature point is the product of the test center temperature correction coefficient, the feature point position correction coefficient and the test temperature of the feature point.

[0036] Furthermore, according to the pre-fitted nonlinear parameters and the position coordinates of the pixels, the pixel position nonlinear correction coefficient is calculated, including:

[0037] Calculate the distance between the pixel and the geometric center of the area to be measured according to the X-coordinate value and the Y-coordinate value of the pixel;

[0038] The nonlinear parameter is used as a base, and the distance between the pixel and the geometric center of the area to be measured is used as an exponent to calculate a value obtained as the nonlinear correction coefficient of the pixel position.

[0039] Furthermore, the correction temperature of the corresponding pixel is the product of the pixel position nonlinear correction coefficient, the central pixel temperature correction coefficient, the pixel position correction coefficient and the measured temperature of the pixel.

[0040] A temperature correction device based on an infrared dot matrix temperature measuring sensor, comprising:

[0041] The temperature acquisition module is used to collect the temperature distribution map of the area to be measured using an infrared dot matrix temperature sensor;

[0042] An actual temperature acquisition module, used to obtain the actual temperature at the geometric center of the area to be measured through a standard thermometer;

[0043] A measurement temperature acquisition module, used to obtain the measurement temperature of each pixel according to the temperature distribution map;

[0044] A center correction coefficient calculation module, used to obtain a center pixel temperature correction coefficient according to the actual temperature at the geometric center of the area to be measured and the measured temperature at the geometric center of the area to be measured;

[0045] A position correction coefficient calculation module, used for obtaining a pixel position correction coefficient according to the position coordinates of the pixels in the temperature distribution map;

[0046] A nonlinear correction coefficient calculation module is used to obtain a pixel position nonlinear correction coefficient according to the pre-fitted nonlinear parameters and the pixel position coordinates;

[0047] The correction temperature calculation module is used to calculate the correction temperature of the corresponding pixel according to the pixel position nonlinear correction coefficient, the central pixel temperature correction coefficient, the pixel position correction coefficient and the measured temperature of the pixel.

[0048] Furthermore, the infrared dot matrix temperature sensor includes m rows and n columns of infrared temperature sensing units, each infrared temperature sensing unit corresponds to a pixel in the temperature distribution map, wherein m and n are both greater than or equal to 2.

[0049] Furthermore, the central pixel temperature correction coefficient is a ratio of the actual temperature at the geometric center of the area to be measured to the measured temperature at the geometric center of the area to be measured.

[0050] Furthermore, the position correction coefficient calculation module obtains the pixel position correction coefficient according to the position coordinates of the pixels in the temperature distribution map, including:

[0051] The geometric center of the area to be measured is set as the origin, the horizontal symmetry axis of the area to be measured is the X axis, and the vertical symmetry axis is the Y axis, to establish a field of view coordinate system;

[0052] Obtaining the maximum column viewing angle of the infrared dot matrix temperature measuring sensor, and calculating the distance from the infrared dot matrix temperature measuring sensor to the geometric center of the area to be measured according to the maximum X coordinate of the area to be measured and the maximum column viewing angle;

[0053] The distance from the infrared dot matrix temperature sensor to the geometric center of the area to be measured is taken as the Z coordinate, and the distance from the pixel to the infrared dot matrix temperature sensor is calculated according to the X coordinate value, the Y coordinate value and the Z coordinate of the pixel;

[0054] The ratio of the distance from the pixel to the infrared dot matrix temperature measuring sensor to the Z coordinate is used as the pixel position correction coefficient.

[0055] Furthermore, the nonlinear correction coefficient calculation module pre-fits to obtain nonlinear parameters, including:

[0056] Cover the test area with the test field of view of the infrared dot matrix temperature sensor, and collect the test temperature distribution diagram of the test area;

[0057] Obtaining the actual test temperature at the geometric center of the test field of view by a standard thermometer;

[0058] Selecting a plurality of characteristic points on the test temperature distribution diagram, obtaining the test temperatures of the characteristic points, and obtaining the test temperature at the geometric center of the test field of view;

[0059] The geometric center of the test field of view is taken as the origin, the horizontal symmetry axis of the test field of view is taken as the X-axis, and the vertical symmetry axis is taken as the Y-axis, a test field of view coordinate system is established, and the pixel coordinates of the plurality of feature points are obtained;

[0060] Calculate and obtain a test center temperature correction coefficient based on the actual test temperature at the geometric center of the test field of view and the test temperature thereof;

[0061] According to the pixel coordinates of each feature point, the feature point position correction coefficient is calculated;

[0062] Calculate and obtain the rough correction temperature of the characteristic point according to the test center temperature correction coefficient, the characteristic point position correction coefficient and the test temperature of the characteristic point;

[0063] A coordinate system is established with the distance from the feature point to the geometric center of the test field of view as the horizontal coordinate and the temperature as the vertical coordinate;

[0064] Marking the feature point rough correction temperature and the test temperature of the feature point in the coordinate system and performing fitting to obtain an exponential function curve;

[0065] The base of the exponential function curve is calculated and obtained as the nonlinear parameter.

[0066] Furthermore, the rough correction temperature of the feature point is the product of the test center temperature correction coefficient, the feature point position correction coefficient and the test temperature of the feature point.

[0067] Furthermore, the nonlinear correction coefficient calculation module calculates the pixel position nonlinear correction coefficient according to the pre-fitted nonlinear parameters and the pixel position coordinates, including:

[0068] Calculate the distance between the pixel and the geometric center of the area to be measured according to the X-coordinate value and the Y-coordinate value of the pixel;

[0069] The nonlinear parameter is used as a base, and the distance between the pixel and the geometric center of the area to be measured is used as an exponent to calculate a value obtained as the nonlinear correction coefficient of the pixel position.

[0070] Furthermore, the correction temperature of the corresponding pixel is the product of the pixel position nonlinear correction coefficient, the central pixel temperature correction coefficient, the pixel position correction coefficient and the measured temperature of the pixel.

[0071] An electronic device comprises a processor and a storage device, wherein the storage device stores a plurality of instructions, and the processor is used to read the instructions and execute the above method.

[0072] The temperature correction method and device based on the infrared dot matrix temperature measuring sensor provided by the present invention have at least the following beneficial effects:

[0073] (1) An infrared dot matrix temperature sensor is used for temperature measurement. Within the coverage range of its field of view, the measured temperature is corrected by the central temperature of the measured area and the position relationship of each pixel. Only one infrared dot matrix temperature sensor and one actual measurement of the central temperature are needed to measure the temperature of each position in a large area. The corrected temperature error is small, which is particularly suitable for temperature measurement of terminal blocks in control cabinets, effectively reducing production costs.

[0074] (2) When measuring a surface area that is much smaller than the field of view of the infrared dot matrix thermometer, the temperature measured by the infrared dot matrix thermometer is approximately inversely proportional to the distance. By calculating and fitting the correlation coefficient based on the position and distance, and fitting the correction coefficient based on the center temperature of the field of view, the final corrected temperature error is small, which meets the temperature measurement requirements of the terminal block. BRIEF DESCRIPTION OF THE DRAWINGS

[0075] Figure 1 The present invention provides a flow chart of an embodiment of a temperature correction method based on an infrared dot matrix temperature measuring sensor.

[0076] Figure 2 The present invention provides a flow chart of an embodiment of the field of view in the temperature correction method based on the infrared dot matrix temperature measuring sensor provided by the present invention.

[0077] Figure 3 The present invention provides a flow chart of an embodiment of calculating pixel position correction coefficients in a temperature correction method based on an infrared dot matrix temperature measuring sensor.

[0078] Figure 4 The present invention provides a flowchart of an embodiment of fitting nonlinear parameters in a temperature correction method based on an infrared dot matrix temperature measuring sensor.

[0079] Figure 5 The present invention provides a flow chart of an embodiment of a temperature correction device based on an infrared dot matrix temperature measuring sensor. DETAILED DESCRIPTION

[0080] In order to better understand the above technical solution, the above technical solution will be described in detail below in conjunction with the accompanying drawings and specific implementation methods.

[0081] refer to Figure 1 In some embodiments, a temperature calibration method based on an infrared dot matrix temperature sensor is provided, comprising:

[0082] S1, using an infrared dot matrix temperature sensor to collect the temperature distribution map of the area to be measured;

[0083] S2. Obtaining the actual temperature at the geometric center of the area to be measured by a standard thermometer;

[0084] S3. Obtaining a measured temperature of each pixel according to the temperature distribution map;

[0085] S4, obtaining a central pixel temperature correction coefficient according to the actual temperature at the geometric center of the area to be measured and the measured temperature at the geometric center of the area to be measured;

[0086] S5, obtaining a pixel position correction coefficient according to the position coordinates of the pixels in the temperature distribution map;

[0087] S6, obtaining a pixel position nonlinear correction coefficient according to the pre-fitted nonlinear parameters and the pixel position coordinates;

[0088] S7. Calculate and obtain the correction temperature of the corresponding pixel according to the pixel position nonlinear correction coefficient, the central pixel temperature correction coefficient, the pixel position correction coefficient and the measured temperature of the pixel.

[0089] Specifically, refer to Figure 2 In step S1, the infrared dot matrix temperature sensor includes m rows and n columns of infrared temperature sensing units, each infrared temperature sensing unit corresponds to a pixel in the temperature distribution map, wherein m and n are both greater than or equal to 2.

[0090] Furthermore, in step S2, the actual temperature at the geometric center of the measured area is obtained by a standard thermometer, and the actual temperature is used as a calculation parameter for the subsequent correction coefficient.

[0091] Furthermore, in step S3, the measured temperature of each pixel is obtained according to the temperature distribution diagram, that is, the measured temperature value collected by each infrared temperature sensing unit.

[0092] Further, in step S4, a central pixel temperature correction coefficient is calculated based on the actual temperature and the measured temperature at the geometric center of the measured area. Specifically, the central pixel temperature correction coefficient is the ratio of the actual temperature at the geometric center of the measured area to the measured temperature at the geometric center of the measured area, as shown in the following formula:

[0093] K c =T c ÷T ic ; (1)

[0094] Among them, T c is the actual temperature at the geometric center of the measured area, T ic is the measured temperature at the geometric center of the measured area, K c is the center pixel temperature correction coefficient.

[0095] The measured temperature at the center of the measured area is relatively accurate, so it is used as the calculation basis for other pixel temperatures, and the ratio of the actual temperature at the geometric center of the measured area to the measured temperature is used as the center pixel temperature correction coefficient.

[0096] Further, refer to Figure 3 In step S5, the pixel position correction coefficient is calculated according to the position coordinates of the pixels in the temperature distribution map, including:

[0097] S51, setting the geometric center of the area to be measured as the origin, the horizontal symmetry axis of the area to be measured as the X axis, and the vertical symmetry axis as the Y axis, to establish a field of view coordinate system;

[0098] S52, obtaining the maximum column viewing angle of the infrared dot matrix temperature measuring sensor, and calculating the distance from the infrared dot matrix temperature measuring sensor to the geometric center of the area to be measured according to the maximum X coordinate in the field of view coordinate system and the maximum column viewing angle;

[0099] S53, taking the distance from the infrared dot matrix temperature sensor to the geometric center of the area to be measured as the Z coordinate, and calculating the distance from the pixel to the infrared dot matrix temperature sensor according to the X coordinate value, the Y coordinate value and the Z coordinate of the pixel;

[0100] S54, taking the ratio of the distance from the pixel to the infrared dot matrix temperature sensor to the Z coordinate as a pixel position correction coefficient.

[0101] Specifically, in step S51, the geometric center of the area to be measured is set as the origin, the horizontal axis of symmetry of the area to be measured is used as the X-axis, and the vertical axis of symmetry of the area to be measured is used as the Y-axis to establish a field of view coordinate system.

[0102] In step S52, the line connecting the infrared dot matrix temperature sensor to the geometric center of the measured area is used as the central axis. Figure 2 , obtain the angle between the central axis and the line connecting the maximum column coordinate on the X-axis to the infrared dot matrix temperature sensor. This angle is the maximum column viewing angle of the infrared dot matrix temperature sensor. According to the maximum column viewing angle θ of the infrared dot matrix temperature sensor and the maximum X-coordinate of the area to be measured, the distance from the infrared dot matrix temperature sensor to the geometric center of the area to be measured can be calculated:

[0103] Z=X max / tanθ; (2)

[0104] Wherein, Z represents the distance from the infrared dot matrix temperature sensor to the geometric center of the measured area, X max represents the maximum X coordinate, and θ represents the maximum column viewing angle of the infrared dot matrix temperature sensor.

[0105] The calculated distance from the infrared dot matrix temperature sensor to the geometric center of the area to be measured is not the distance in the actual physical space, but the distance calculated in the field of view coordinate system with the set coordinate spacing as the unit.

[0106] Further, in step S53, the distance from the infrared dot matrix temperature sensor to the geometric center of the measured area is taken as the Z coordinate, and the distance from the pixel to the infrared dot matrix temperature sensor is calculated according to the X coordinate value, Y coordinate value and the Z coordinate of the pixel: (X 2 +Y 2 +Z 2 ) 1 / 2 .

[0107] Furthermore, in step S54, the ratio of the distance from the pixel to the infrared dot matrix temperature sensor to the Z coordinate is used as the pixel position correction coefficient, that is:

[0108] K l =((X 2 +Y 2 +Z 2 ) 1 / 2 ) / Z; (3)

[0109] Among them, K l is the pixel position correction coefficient, X is the X coordinate value of the pixel, Y is the Y coordinate value of the pixel, and Z is the Z coordinate.

[0110] When measuring a surface area that is much smaller than the field of view of the infrared dot matrix thermometer, the temperature measured by the infrared dot matrix thermometer is approximately inversely proportional to the distance. Based on this, the ratio of the distance from the pixel to the infrared dot matrix temperature sensor to the Z coordinate is used as the pixel position correction coefficient.

[0111] Further, refer to Figure 4 In step S6, pre-fitting to obtain nonlinear parameters includes:

[0112] S61, covering the test area with the test field of view of the infrared dot matrix temperature sensor, and collecting a test temperature distribution diagram of the test area;

[0113] S62, obtaining the actual test temperature at the geometric center of the test field of view by a standard thermometer;

[0114] S63, selecting a plurality of characteristic points on the test temperature distribution diagram, obtaining the test temperatures of the characteristic points, and obtaining the test temperature at the geometric center of the test field of view;

[0115] S64, taking the geometric center of the test field of view as the origin, the horizontal symmetry axis of the test field of view as the X-axis, and the vertical symmetry axis as the Y-axis, to establish a test field of view coordinate system, and obtain the pixel coordinates of the multiple feature points;

[0116] S65, calculating and obtaining a test center temperature correction coefficient according to the actual test temperature at the geometric center of the test field of view and the test temperature thereof;

[0117] S66, calculating and obtaining feature point position correction coefficients according to the pixel coordinates of each feature point;

[0118] S67, calculating and obtaining a rough correction temperature of the characteristic point according to the test center temperature correction coefficient, the characteristic point position correction coefficient and the test temperature of the characteristic point;

[0119] S68, establishing a coordinate system with the distance from the characteristic point to the geometric center of the test field of view as the abscissa and the temperature as the ordinate;

[0120] S69, marking the feature point rough correction temperature and the test temperature of the feature point in the coordinate system and performing fitting to obtain an exponential function curve;

[0121] S610: Calculate and obtain the base of the exponential function curve as the nonlinear parameter.

[0122] Specifically, in step S61, Figure 2 As shown, the test field of view of the infrared dot matrix temperature sensor covers the test area, and a test temperature distribution diagram of the test area is collected. In the test temperature distribution diagram, each pixel, i.e., the test temperature obtained by each infrared temperature sensing unit in the infrared dot matrix temperature sensor.

[0123] Furthermore, in step S62, the actual test temperature at the geometric center of the test field of view is obtained by a standard thermometer, and the actual test temperature at the geometric center of the test field of view is used as a parameter for subsequent calculation of the correction coefficient.

[0124] Further, in step S63, multiple feature points are selected on the test temperature distribution map, the test temperatures of the feature points are obtained, and the test temperature at the geometric center of the test field of view is obtained. Specifically, multiple feature points are evenly distributed on the test temperature distribution map, and the test temperature of each feature point is obtained through the test temperature distribution map.

[0125] Furthermore, in step S64, the geometric center of the test field of view is taken as the origin, that is, the horizontal axis of symmetry of the test field of view is taken as the X-axis, the vertical axis of symmetry is taken as the Y-axis, and each infrared temperature sensor unit is taken as a unit, and a test field of view coordinate system is established to obtain the pixel coordinates of the multiple feature points.

[0126] Furthermore, in step S65, a test center temperature correction coefficient is calculated based on the actual test temperature and the test temperature at the geometric center of the test field of view. Specifically, the calculation can be performed using formula (1), that is, the test center temperature correction coefficient is the ratio of the actual test temperature at the geometric center of the test field of view to the test temperature at the geometric center of the test field of view.

[0127] Furthermore, in step S66, the feature point position correction coefficient is calculated based on the pixel coordinates of each feature point. Specifically, the calculation is performed according to formula (3). The distance from the feature point to the infrared dot matrix temperature sensor is calculated based on the X coordinate value, Y coordinate value and Z coordinate of the feature point, and then the ratio of the distance to the Z coordinate is used as the feature point position correction coefficient.

[0128] Further, in step S67, according to the test center temperature correction coefficient, the feature point position correction coefficient and the test temperature of the feature point, the feature point rough correction temperature is calculated, and the feature point rough correction temperature is the product of the test center temperature correction coefficient, the feature point position correction coefficient and the test temperature of the feature point, that is:

[0129] T (a,b),q = K c '×K l '×T (a,b) ; (4)

[0130] Among them, T (a,b),q is the rough correction temperature of the feature point in row a and column b, K c ' is the test center temperature correction coefficient, K l ' is the feature point position correction coefficient, T (a,b) is the test temperature of the characteristic point in row a and column b.

[0131] Furthermore, in step S68, a coordinate system is established with the distance from the feature point to the geometric center of the test field of view as the abscissa and the temperature as the ordinate.

[0132] In step S69, the rough correction temperatures T of the plurality of characteristic points obtained by calculation are (a,b),q , and its test temperature T (a,b) are not equal, so the feature point rough correction temperature and the test temperature of the feature point are marked in the coordinate system and fitted to obtain an exponential function curve, the independent variable of the exponential function is the distance from the feature point to the geometric center of the test field of view, and the dependent variable is temperature.

[0133] In step S610, the base of the exponential function curve is calculated, and the base is the nonlinear parameter.

[0134] Furthermore, in step S6, the pixel position nonlinear correction coefficient is calculated based on the pre-fitted nonlinear parameters and the pixel position coordinates, including:

[0135] S611, calculating the distance between the pixel and the geometric center of the area to be measured according to the X coordinate value and the Y coordinate value of the pixel;

[0136] S612: Use the nonlinear correction coefficient as a base and the distance between the pixel and the geometric center of the area to be measured as an exponent to calculate a value as the nonlinear correction coefficient for the pixel position.

[0137] Specifically, in step S611, the distance s between the pixel and the geometric center of the area to be measured is calculated according to the X coordinate value and the Y coordinate value of the pixel, that is:

[0138] s=(X 2 +Y 2 ) 1 / 2 ; (5)

[0139] Wherein, s is the distance between the pixel and the geometric center of the field of view, X is the X coordinate value of the pixel, and Y is the Y coordinate value of the pixel.

[0140] Furthermore, in step S622, the nonlinear parameter is used as the base, and the distance between the pixel and the geometric center of the area to be measured is used as the exponent to calculate the value obtained as the nonlinear correction coefficient of the pixel position, specifically:

[0141] K a =a s ; (6)

[0142] Where a is the nonlinear parameter obtained by fitting, s is the distance between the pixel and the geometric center of the field of view, K a is the nonlinear correction coefficient of the pixel position.

[0143] Further, in step S7, the correction temperature of the corresponding pixel is the product of the pixel position nonlinear correction coefficient, the central pixel temperature correction coefficient, the pixel position correction coefficient and the measured temperature of the pixel, specifically:

[0144] T (i，j) '= K c ×K l ×K a ×T (i，j) ; (7)

[0145] Among them, T (i，j) ' represents the corrected temperature of the pixel in the i-th row and j-th column, K a is the pixel position nonlinear correction coefficient, K cis the center pixel temperature correction coefficient, K l Pixel position correction factor, T (i，j) is the measured temperature of the pixel at the i-th row and j-th column.

[0146] The above method is further explained below through a specific application scenario.

[0147] Assume that the infrared dot matrix temperature sensor is composed of 24 rows and 24 columns of infrared temperature sensing units, and each infrared temperature sensing unit outputs a measured temperature value as a pixel.

[0148] The measured temperature at the geometric center of the field of view measured by the infrared dot matrix temperature sensor is 47°C, and the actual temperature at the geometric center of the field of view collected by the standard thermometer is 53.2°C.

[0149] The pixel coordinates of the specific position to be measured are (10, 10), the measurement temperature is 22°C, and the maximum column coordinate of the field of view is X max is 12, and the maximum column viewing angle θ is 37.5°.

[0150] Center pixel temperature correction coefficient K c =53.2÷47=1.13.

[0151] Z coordinate Z = X max ÷tanθ=12÷tan37.5=15.64.

[0152] Pixel position correction coefficient K l =((X 2 +Y 2 +Z 2 ) 1 / 2 )÷Z=((10 2 +10 2 +15.64 2 ) 1 / 2 )÷15.64=1.32.

[0153] The distance between the pixel and the geometric center of the field of view is s = (X 2 +Y 2 ) 1 / 2 =(102+102)1 / 2=14.14.

[0154] The nonlinear parameter obtained by fitting is 1.012, so the pixel position nonlinear correction coefficient K a =1.012 s =1.012 14.14 =1.18.

[0155] Finally calculate the corrected temperature:

[0156] T (10,10) '=Kc ×K l ×K a ×T (10,10) =1.13×1.32×1.18

[0157] ×22=38.72℃

[0158] After calculation, the corrected temperature is 38.72℃.

[0159] The measured temperature of the corresponding terminal is 40.2℃, with an error of 3.7%. The error is extremely small and the measurement is valid.

[0160] refer to Figure 5 In some embodiments, a temperature calibration device based on an infrared dot matrix temperature sensor is provided, comprising:

[0161] The temperature acquisition module 201 is used to acquire the temperature distribution diagram of the area to be measured by using an infrared dot matrix temperature measurement sensor;

[0162] The actual temperature acquisition module 202 is used to obtain the actual temperature at the geometric center of the test area through a standard thermometer;

[0163] A measured temperature acquisition module 203, used to obtain the measured temperature of each pixel according to the temperature distribution map;

[0164] The center correction coefficient calculation module 204 is used to obtain the center pixel temperature correction coefficient according to the actual temperature at the geometric center of the area to be measured and the measured temperature at the geometric center of the area to be measured;

[0165] A position correction coefficient calculation module 205, used to obtain a pixel position correction coefficient according to the position coordinates of the pixels in the temperature distribution map;

[0166] The nonlinear correction coefficient calculation module 206 is used to calculate the nonlinear correction coefficient of the pixel position according to the pre-fitted nonlinear parameters and the position coordinates of the pixel;

[0167] The correction temperature calculation module 206 is used to calculate the correction temperature of the corresponding pixel according to the pixel position nonlinear correction coefficient, the central pixel temperature correction coefficient, the pixel position correction coefficient and the measured temperature of the pixel.

[0168] Furthermore, the infrared dot matrix temperature sensor includes m rows and n columns of infrared temperature sensing units, each infrared temperature sensing unit corresponds to a pixel in the temperature distribution map, wherein m and n are both greater than or equal to 2.

[0169] Furthermore, the central pixel temperature correction coefficient is a ratio of the actual temperature at the geometric center of the area to be measured to the measured temperature at the geometric center of the area to be measured.

[0170] Furthermore, the position correction coefficient calculation module 205 calculates the pixel position correction coefficient according to the position coordinates of the pixels in the temperature distribution map, including:

[0171] The geometric center of the area to be measured is set as the origin, the horizontal symmetry axis of the area to be measured is the X-axis, and the vertical symmetry axis is the Y-axis, to establish a field of view coordinate system;

[0172] Obtaining the maximum column viewing angle of the infrared dot matrix temperature measuring sensor, and calculating the distance from the infrared dot matrix temperature measuring sensor to the geometric center of the area to be measured according to the maximum X coordinate of the area to be measured and the maximum column viewing angle;

[0173] The distance from the infrared dot matrix temperature sensor to the geometric center of the area to be measured is taken as the Z coordinate, and the distance from the pixel to the infrared dot matrix temperature sensor is calculated according to the X coordinate value, the Y coordinate value and the Z coordinate of the pixel;

[0174] The ratio of the distance from the pixel to the infrared dot matrix temperature measuring sensor to the Z coordinate is used as the pixel position correction coefficient.

[0175] Furthermore, the nonlinear correction coefficient calculation module 206 pre-fits to obtain nonlinear parameters, including:

[0176] Cover the test area with the test field of view of the infrared dot matrix temperature sensor, and collect the test temperature distribution diagram of the test area;

[0177] Obtaining the actual test temperature at the geometric center of the test field of view by a standard thermometer;

[0178] Selecting a plurality of characteristic points on the test temperature distribution diagram, obtaining the test temperatures of the characteristic points, and obtaining the test temperature at the geometric center of the test field of view;

[0179] The geometric center of the test field of view is taken as the origin, the horizontal symmetry axis of the test field of view is taken as the X-axis, and the vertical symmetry axis is taken as the Y-axis, a test field of view coordinate system is established, and the pixel coordinates of the plurality of feature points are obtained;

[0180] Calculate and obtain a test center temperature correction coefficient based on the actual test temperature at the geometric center of the test field of view and the test temperature thereof;

[0181] According to the pixel coordinates of each feature point, the feature point position correction coefficient is calculated;

[0182] Calculate and obtain the rough correction temperature of the characteristic point according to the test center temperature correction coefficient, the characteristic point position correction coefficient and the test temperature of the characteristic point;

[0183] A coordinate system is established with the distance from the feature point to the geometric center of the test field of view as the horizontal coordinate and the temperature as the vertical coordinate;

[0184] Marking the feature point rough correction temperature and the test temperature of the feature point in the coordinate system and performing fitting to obtain an exponential function curve;

[0185] The base of the exponential function curve is calculated and obtained as the nonlinear parameter.

[0186] Furthermore, the rough correction temperature of the feature point is the product of the test center temperature correction coefficient, the feature point position correction coefficient and the test temperature of the feature point.

[0187] Furthermore, the nonlinear correction coefficient calculation module 206 calculates the pixel position nonlinear correction coefficient according to the pre-fitted nonlinear parameters and the pixel position coordinates, including:

[0188] Calculate the distance between the pixel and the geometric center of the area to be measured according to the X-coordinate value and the Y-coordinate value of the pixel;

[0189] The nonlinear parameter is used as a base, and the distance between the pixel and the geometric center of the area to be measured is used as an exponent to calculate a value obtained as the nonlinear correction coefficient of the pixel position.

[0190] Furthermore, the correction temperature of the corresponding pixel is the product of the pixel position nonlinear correction coefficient, the central pixel temperature correction coefficient, the pixel position correction coefficient and the measured temperature of the pixel.

[0191] Please refer to the above embodiments for the specific working principle, which will not be described in detail here.

[0192] In some embodiments, an electronic device is also provided, including a processor and a storage device, wherein the storage device stores a plurality of instructions, and the processor is used to read the instructions and execute the above method.

[0193] The temperature correction method and device based on the infrared dot matrix temperature sensor provided in the above embodiment have at least the following beneficial effects:

[0194] (1) An infrared dot matrix temperature sensor is used for temperature measurement. Within the coverage range of its field of view, the measured temperature is corrected by the central temperature of the field of view and the position relationship of each pixel. Only one infrared dot matrix temperature sensor and one actual measurement of the central temperature are needed to measure the temperature of each position in a large area. The corrected temperature error is small, which is particularly suitable for temperature measurement of terminal blocks in control cabinets, effectively reducing production costs.

[0195] (2) When measuring a surface area that is much smaller than the field of view of the infrared dot matrix thermometer, the temperature measured by the infrared dot matrix thermometer is approximately inversely proportional to the distance. By calculating and fitting the correlation coefficient based on the position and distance, and fitting the correction coefficient based on the center temperature of the field of view, the final corrected temperature error is small, which meets the temperature measurement requirements of the terminal block.

[0196] Although preferred embodiments of the present invention have been described, additional changes and modifications may be made to these embodiments by those skilled in the art once the basic inventive concepts are known. Therefore, the appended claims are intended to be interpreted as including the preferred embodiments and all changes and modifications that fall within the scope of the present invention. Obviously, those skilled in the art may make various changes and modifications to the present invention without departing from the spirit and scope of the present invention. Thus, if these modifications and variations of the present invention fall within the scope of the claims of the present invention and their equivalents, the present invention is also intended to include these modifications and variations.

Claims

1. A temperature correction method based on an infrared dot matrix temperature sensor, characterized in that: include: Use infrared dot matrix temperature sensor to collect the temperature distribution map of the area to be measured; Obtaining the actual temperature at the geometric center of the area to be measured by a standard thermometer; According to the temperature distribution map, obtaining the measured temperature of each pixel; Obtaining a center pixel temperature correction coefficient according to the actual temperature at the geometric center of the area to be measured and the measured temperature at the geometric center of the area to be measured; Obtaining a pixel position correction coefficient according to the position coordinates of the pixels in the temperature distribution map; Obtaining a pixel position nonlinear correction coefficient according to the pre-fitted nonlinear parameters and the pixel position coordinates; The correction temperature of the corresponding pixel is calculated based on the pixel position nonlinear correction coefficient, the central pixel temperature correction coefficient, the pixel position correction coefficient and the measured temperature of the pixel.

2. The method according to claim 1, characterized in that: The infrared dot matrix temperature sensor includes m rows and n columns of infrared temperature sensing units, each of which corresponds to a pixel in the temperature distribution map, wherein m and n are both greater than or equal to 2.

3. The method according to claim 1, characterized in that The central pixel temperature correction coefficient is the ratio of the actual temperature at the geometric center of the area to be measured to the measured temperature at the geometric center of the area to be measured.

4. The method according to claim 1, characterized in that: Obtaining a pixel position correction coefficient according to the position coordinates of the pixels in the temperature distribution map includes: The geometric center of the area to be measured is set as the origin, the horizontal symmetry axis of the area to be measured is the X-axis, and the vertical symmetry axis is the Y-axis, to establish a field of view coordinate system; Obtaining the maximum column viewing angle of the infrared dot matrix temperature measuring sensor, and calculating the distance from the infrared dot matrix temperature measuring sensor to the geometric center of the area to be measured according to the maximum X coordinate of the area to be measured and the maximum column viewing angle; The distance from the infrared dot matrix temperature sensor to the geometric center of the area to be measured is taken as the Z coordinate, and the distance from the pixel to the infrared dot matrix temperature sensor is calculated according to the X coordinate value, the Y coordinate value and the Z coordinate of the pixel; The ratio of the distance from the pixel to the infrared dot matrix temperature measuring sensor to the Z coordinate is used as the pixel position correction coefficient.

5. The method according to claim 1, characterized in that Pre-fitting to obtain nonlinear parameters, including: Cover the test area with the test field of view of the infrared dot matrix temperature sensor, and collect the test temperature distribution diagram of the test area; Obtaining the actual test temperature at the geometric center of the test field of view by a standard thermometer; Selecting a plurality of characteristic points on the test temperature distribution diagram, obtaining the test temperatures of the characteristic points, and obtaining the test temperature at the geometric center of the test field of view; The geometric center of the test field of view is taken as the origin, the horizontal symmetry axis of the test field of view is taken as the X-axis, and the vertical symmetry axis is taken as the Y-axis, a test field of view coordinate system is established, and the pixel coordinates of the plurality of feature points are obtained; Calculate and obtain a test center temperature correction coefficient based on the actual test temperature at the geometric center of the test field of view and the test temperature thereof; According to the pixel coordinates of each feature point, the feature point position correction coefficient is calculated; Calculate and obtain the rough correction temperature of the characteristic point according to the test center temperature correction coefficient, the characteristic point position correction coefficient and the test temperature of the characteristic point; A coordinate system is established with the distance from the feature point to the geometric center of the test field of view as the horizontal coordinate and the temperature as the vertical coordinate; Marking the feature point rough correction temperature and the test temperature of the feature point in the coordinate system and performing fitting to obtain an exponential function curve; The base of the exponential function curve is calculated and obtained as the nonlinear parameter.

6. The method according to claim 5, characterized in that The rough correction temperature of the feature point is the product of the test center temperature correction coefficient, the feature point position correction coefficient and the test temperature of the feature point.

7. The method according to claim 1 or 5, characterized in that: According to the pre-fitted nonlinear parameters and the pixel position coordinates, the pixel position nonlinear correction coefficient is calculated, including: Calculate the distance between the pixel and the geometric center of the area to be measured according to the X-coordinate value and the Y-coordinate value of the pixel; The nonlinear parameter is used as a base, and the distance between the pixel and the geometric center of the area to be measured is used as an exponent to calculate a value obtained as the nonlinear correction coefficient of the pixel position.

8. The method according to claim 1, characterized in that: The correction temperature of the corresponding pixel is the product of the pixel position nonlinear correction coefficient, the central pixel temperature correction coefficient, the pixel position correction coefficient and the measured temperature of the pixel.

9. A temperature calibration device based on an infrared dot matrix temperature sensor, characterized in that: include: The temperature acquisition module is used to collect the temperature distribution map of the area to be measured using an infrared dot matrix temperature sensor; An actual temperature acquisition module, used to obtain the actual temperature at the geometric center of the area to be measured through a standard thermometer; A measurement temperature acquisition module, used to obtain the measurement temperature of each pixel according to the temperature distribution map; A center correction coefficient calculation module, used to obtain a center pixel temperature correction coefficient according to the actual temperature at the geometric center of the area to be measured and the measured temperature at the geometric center of the area to be measured; A position correction coefficient calculation module, used for obtaining a pixel position correction coefficient according to the position coordinates of the pixels in the temperature distribution map; A nonlinear correction coefficient calculation module is used to obtain a pixel position nonlinear correction coefficient according to the pre-fitted nonlinear parameters and the pixel position coordinates; The correction temperature calculation module is used to calculate the correction temperature of the corresponding pixel according to the pixel position nonlinear correction coefficient, the central pixel temperature correction coefficient, the pixel position correction coefficient and the measured temperature of the pixel.

10. An electronic device, characterized in that: The method comprises a processor and a storage device, wherein the storage device stores a plurality of instructions, and the processor is used to read the instructions and execute the method according to any one of claims 1 to 8.

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