Self-calibration air thermal aging test equipment

Abstract

The invention discloses self-calibration air thermal aging test equipment, and the equipment comprises a self-calibration system which is used for obtaining the working space temperature and environment temperature of the test equipment, and measuring the heating power of the air thermal aging test equipment; the control system is used for calculating and processing to obtain the current actual temperature, the environment temperature and the actual air exchange rate of the air thermal aging test equipment, correcting by taking the difference between the actual temperature and the temperature required by the test as the temperature deviation, and sending the difference between the actual air exchange rate and the required air exchange rate as the air exchange rate deviation to the self-calibration system; the self-calibration system is used for comparing the actual air exchange rate data with the actual required air exchange rate, controlling the servo motor to drive the air exchange fan blades of the air thermal aging test equipment to rotate so as to adjust the air exchange rate of the thermal aging air test box, re-calculating the actual air exchange rate, updating the air exchange rate data of all the rotating positions of the servo motor, and outputting the updated air exchange rate data. And the accuracy of subsequent ventilation rate adjustment is ensured. The experimental parameter accuracy and stability of the equipment can be improved.

Description

Technical Field

[0001] The present invention belongs to the technical field of thermal aging test equipment, and particularly relates to a self-calibrating air thermal aging test equipment. Background Technique

[0002] An air thermal aging test equipment is a common environmental test equipment for conducting thermal aging tests on experimental samples under high temperature and air circulation replacement conditions. Its main characteristic parameters are temperature and air change rate; for temperature calibration, since the structure of the equipment box itself is ventilated rather than sealed, there are certain differences in the temperature fields of the upper and lower layers. The conventional method of calculating the temperature deviation based on the center point of the equipment and then correcting it cannot guarantee the overall accuracy of the box temperature; the air change rate is obtained by converting the electric energy consumed by the internal heating system in combination with comprehensive parameters such as temperature, specific heat of air, and air density. Generally, the size of the air vent regulating valve is manually adjusted according to actual needs, and then the air change rate after adjustment is repeatedly measured, and then the air change rate is adjusted again until the air change rate error is within an acceptable range. The calibration process is relatively complex and requires repeated calibration many times.

[0003] The problems existing in the current calibration methods are as follows: 1. It is difficult to ensure the overall temperature accuracy by correcting with the center temperature; 2. There are certain deviations between the acquisition methods of the specific heat of air and air density in the air change rate calculation parameters and the actual working conditions; 3. The manual adjustment of the air change rate mainly relies on personal experience, and the adjustment error is large; 4. Most adjustments require repeated measurements, and after confirming the error, adjustments are made again, consuming a large amount of labor and time costs, and the work efficiency is low. Summary of the Invention

[0004] The purpose of the present invention is to provide an air thermal aging test equipment with a self-calibration function, which uses a self-calibration system to accurately measure the temperature and air change rate, combines the difference from the actually required air change rate, feeds back the signal to the air change rate self-calibration system, and the system can automatically adjust the air change rate error at one time, eliminate the empirical error of manual adjustment, improve the work efficiency, and further improve the accuracy and stability of the experimental parameters of the air thermal aging test equipment.

[0005] The technical solution for achieving the purpose of the present invention is as follows:

[0006] A self-calibrating air thermal aging test equipment, comprising:

[0007] A self-calibration system for measuring the temperature inside and outside the air thermal aging test equipment to obtain the working space temperature and ambient temperature of the test equipment, and measuring the heating power of the air thermal aging test equipment;

[0008] A control system that receives the data measured by the self-calibration system, calculates and processes to obtain the current actual temperature t s s of the air thermal aging test equipment, the ambient temperature T p pand the actual air change rate N k , with the actual temperature t s and the experimental required temperature t m The difference is used as the temperature deviation for correction. With the actual air change rate N k and the required air change rate N j The difference is used as the air change rate deviation and sent to the self-calibration system;

[0009] The self-calibration system is used to compare the actual air change rate data with the actual required air change rate, control the servo motor to drive the air exchange fan blade of the air thermal aging test equipment to rotate, adjust the air change rate of the thermal aging air test chamber, and re-measure the actual air change rate, update the air change rate data at all positions of the servo motor rotation to ensure the accuracy of subsequent air change rate adjustment.

[0010] Compared with the prior art, the significant advantages of the present invention are:

[0011] Using the average value of multi-point temperature measurements inside the box as the actual temperature of the box, correcting and calibrating the temperature deviation, and at the same time using it as the working space temperature of the test equipment during the calculation of the air change rate, improving the calibration accuracy;

[0012] In view of the fact that the measurement time of the air change rate is long and the thermal aging experiment has been in a high-temperature air exchange state, so the surrounding environment temperature is always changing during the measurement process. The present invention obtains a more accurate environmental temperature change trend by fitting the measured environmental temperature using the least squares method, and then calculates the average temperature within the time period through integration. Combining with the density calculation formula and the constant pressure molar specific heat formula, more accurate specific heat capacity data is calculated to replace the original fixed value or the look-up table method, thereby improving the accuracy of air change rate calculation;

[0013] The single measurement time of the air change rate takes about 2 hours or more. Repeated manual measurement and adjustment consume a large amount of costs. The present invention uses algorithm memory calibration to control the servo motor to drive the rotating fan blade to adjust the air change rate, and through the minimum step angle of the servo motor, completes the one-time automatic calibration of the air change rate, improving the calibration accuracy and working efficiency of the air change rate;

[0014] Adopting the proportional adjustment method to update the calibration algorithm data can achieve the purpose of rapid adjustment and improve the long-term stability of air change rate calibration. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 It is a schematic diagram of the module structure of the present invention.

[0016] Figure 2 It is a flow chart of the algorithm memory calibration of the present invention.

[0017] Figure 3 It is a schematic diagram of the air change rate data update process. DETAILED DESCRIPTION OF THE INVENTION

[0018] The specific embodiments of the present invention will be further described below in conjunction with the accompanying drawings. It should be noted here that the description of these embodiments is used to help understand the present invention, but does not constitute a limitation on the present invention. In addition, the technical features involved in the various embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.

[0019] The present invention provides a self-calibrating air thermal aging test device as Figure 1 shown, which mainly includes a self-calibration system, a control system, and a self-calibration system. The self-calibration system consists of a temperature measurement module and a power measurement module. The control system consists of a temperature control module, a data processing module, and a control interface. The self-calibration system consists of an algorithm control module and an automatic adjustment module.

[0020] The self-calibration system includes a temperature measurement module and a power measurement module;

[0021] The temperature measurement module is configured with 10 aviation plugs. After inserting 10 calibrated Class A platinum resistance thermometers numbered 1-10 into the corresponding aviation plugs, the corresponding calibration correction values are input into the temperature measurement module. The sensing ends of the platinum resistance thermometers numbered 1-9 are placed at the upper, middle, and lower layers inside the box, and the positions are the 4 corner points of the upper layer, the 4 corner points of the lower layer, and the geometric center point of the middle layer respectively. The platinum resistance thermometer numbered 10 is placed outside the test device, about 2 m away from the air inlet of the test device and on the same horizontal plane as the air inlet, and at a position at least 1 m away from other objects; start self-calibration with one key. When the temperature fluctuations of the platinum resistance thermometers numbered 1-9 remain within the set fluctuation limit, the system automatically determines that the test device has entered a stable state, and the average air temperature obtained by integrating the measured temperature data of the platinum resistance thermometer numbered 10 using the least squares method is used as the ambient temperature T p and the average value of all the temperature data of the 9 points measured by the platinum resistance thermometers numbered 1-9 is used as the actual temperature t of the overall box s ;

[0022] The power measurement module is connected in series to the terminals of the internal heating system of the test device, and measures the heating power of the test chamber while measuring the temperature.

[0023] Control system

[0024] The temperature control module consists of a temperature controller and a temperature sensor. The temperature sensor needs to be screened for long-term stability before use, and the temperature controller and the temperature sensor as a whole are calibrated and input error correction is performed to ensure its accuracy and stability; it can also receive the temperature deviation sent by the data processing module and automatically correct the temperature deviation during self-calibration.

[0025] Data processing module: Receives the data from the temperature measurement module and the power measurement module, calculates and processes to obtain the current actual temperature t of the test equipment s , the ambient temperature T p , and the actual air change rate N k . Taking the difference between the actual temperature t s and the required temperature t of the experiment m as the temperature deviation, it is sent to the temperature control module for temperature correction; taking the difference between the actual air change rate N k and the required air change rate N j as the air change rate deviation, it is sent to the self-calibration system, and the air change rate parameters of the test equipment are adjusted and calibrated through the control algorithm, and the algorithm data is updated.

[0026] The air change rate calculation is obtained through the following formula:

[0027]

[0028] Where: N k is the actual air change rate, with the unit of times / h;

[0029] h s is the coefficient (h s = 3600);

[0030] P 1 is the average power when the air inlet is closed, with the unit of W;

[0031] P 2 is the average power when the air inlet is open, with the unit of W;

[0032] c p is the specific heat capacity of air under normal pressure, with the unit of J / (g·°C);

[0033] t 1 is the ambient temperature, with the unit of °C, that is, T p ;

[0034] t 2 is the working space temperature of the test equipment, with the unit of °C, that is, t s ;

[0035] V is the volume of the test equipment box (including the air duct), with the unit of L;

[0036] d is the ambient air density during the test, with the unit of g / L.

[0037] Among them, t 2 is equal to t s , representing the overall actual temperature inside the equipment box;

[0038]

[0039] Where: n is the number of measurements at each temperature point, m is the number of measurement points, and in this embodiment, m = 9; t ij is the temperature value measured for the jth time at the ith measurement point within the specified time, with the unit of °C.

[0040] Under normal pressure, the specific heat capacity of air is usually defined as a fixed value of 1.003 J / (g·°C) in industry standards and other materials. However, the specific heat capacity should be the change amount with the ambient temperature. The specific calculation method is as follows:

[0041] uc p = a 0 + a 1 T + a 2 T 2 + a 3 T 3

[0042] where T is the measured value of the ambient temperature (in the unit of K, that is, the conventional measured Celsius temperature value is converted to the Kelvin temperature value), and a 0 , a 1 , a 2 , a 3 are coefficients related to the gas molecular formula and name, and u is a constant;

[0043] The air density is usually obtained by looking up a table. However, the air density table usually provides data corresponding to whole Celsius degrees of the ambient temperature. Here, a more accurate value of the ambient temperature is obtained by fitting a curve using the least squares method. The air density table usually provides data corresponding to whole Celsius degrees of the ambient temperature. In actual situations, the air density d also changes with the ambient temperature. The specific calculation method is as follows:

[0044]

[0045] where T is the measured value of the ambient temperature (in the unit of K, that is, the conventional measured Celsius temperature value is converted to the Kelvin temperature value), and P is the conventional standard atmospheric pressure of 101.325 kPa.

[0046] Since both the specific heat capacity of air and the air density are parameters that change with the ambient temperature, and the actual site is not a constant temperature room, the ambient temperature also changes with time, and the experimental time is relatively long. Therefore, x measured ambient temperatures obtained at equal intervals during the experimental time are used to obtain the quadratic fitting formula of the ambient temperature T by the least squares method, that is:

[0047] T = b 0 + b 1 t + b 2 t 2

[0048] where t is the time, and b 0 , b 1 , b 2is the quadratic coefficient of the ambient temperature varying with time. By inputting the x - th ambient temperature measured at equal intervals and the corresponding measurement time into MATLAB software, the prediction formula for the temperature change is calculated using MATLAB software. Then, according to the method of polynomial fitting, the quadratic fitting image is drawn using MATLAB software, and the quadratic coefficient and the curve equation are obtained. Thus, the ambient temperature at more time points can be calculated more accurately.

[0049] On this basis, through the x - th ambient temperature values measured within the specified measurement time and the curve equation obtained by fitting, and then through the integral formula, the average temperature T of the ambient temperature values obtained within the specified measurement time is calculated p , as follows:

[0050]

[0051] Among them, within the specified measurement time, that is, from time r 1 to time r 2 ; the average temperature T p is converted to °C to obtain the ambient temperature t 1 .

[0052] The average temperature is calculated by using the integral formula to calculate the specific heat capacity and density of air, as follows:

[0053] uc p = a 0 + a 1 T p + a 2 T p 2 + a 3 T p 3

[0054]

[0055] Through the quadratic fitting formula of the temperature T obtained by the least - squares method, and then through the integral to calculate the average temperature within the time period, combined with the specific heat capacity at constant pressure formula and the dry air density formula, more real and accurate data of the specific heat capacity and density of air in the actual measurement process can be obtained, reducing the uncertainty brought by the dynamic change of the ambient temperature.

[0056] Operation interface: Provide an intuitive interface for users to operate the control system. Users can set the device temperature, control the calibration program, update the algorithm parameters (ventilation rate at each position), etc. on the interface, and view the detection and calibration results.

[0057] The self - calibration system consists of an algorithm control module and an automatic adjustment module;

[0058] The automatic adjustment module is used to control the servo motor to drive the ventilation fan blade of the air thermal aging test equipment to rotate, so as to adjust the ventilation rate of the thermal aging air test chamber.

[0059] Algorithm control module: Compare the actual ventilation rate data obtained through processing with the actual required ventilation rate, and calibrate the ventilation rate of the test equipment by combining the feedback control algorithm, and output it to the automatic adjustment module to dynamically adjust the ventilation rate of the thermal aging air test chamber. The specific calibration method is as follows:

[0060] Step 1: Initial calibration Record the ventilation rate data N max and N min ;

[0061] Step 2: Self-calibration The system controls the servo motor to drive the fan blade on the air outlet of the thermal aging equipment to rotate for ventilation rate adjustment. The minimum step value i (adjustment angle) of the servo motor each time. Calibrate and record the ventilation rate corresponding to the minimum step value i of the servo motor control to adjust the fan blade rotation each time, that is, calibrate and record the ventilation rate N mi corresponding to the angle (0° + mi) of rotating m times, calibrate the ventilation rate N i corresponding to the servo motor rotating i degrees, calibrate the ventilation rate N 2i corresponding to the servo motor rotating 2i degrees, and so on, so as to obtain the ventilation rate difference between each step value. Where m = 0, 1, 2, 3... M, the unit is times, M = 360 / i. It should be noted that the ventilation rate differences between each step value are not the same;

[0062] Step 3: According to the ventilation rate of the current position of the ventilation fan blade automatically measured after the self-calibration starts, judge whether it meets the required ventilation rate requirements according to the deviation between the current position ventilation rate and the required ventilation rate. If it does not meet the requirements, obtain the actual ventilation rate N k corresponding to the current automatic adjustment angle ki of the servo motor and the required ventilation rate N j of the user, the deviation Z, Z = N j -N k , combine the ventilation rate differences of the p times of rotation before and after the current position of the ventilation fan blade located at the kth rotation position of the servo motor with the deviation Z for comparison. The ventilation rate differences of the p times before and after the current position are N (k±p)i -N k , where plus or minus (±) p is determined by the positive or negative value of the deviation Z. When it is positive, Z = N j -N k > 0, indicating that the ventilation rate adjusted by the initial calibration has not reached the required ventilation rate requirements, and the servo motor still needs to rotate in the reverse direction to adjust the fan blade angle to increase the ventilation rate; when it is negative, Z = N j -N k< 0 indicates that the ventilation rate adjusted through the initial calibration exceeds the required ventilation rate, and the servo motor needs to rotate forward to adjust the blade angle and reduce the ventilation rate; take the ventilation rate difference closest to the deviation Z, and combine this ventilation rate difference with the ventilation rate differences between the minimum step values of the initial calibration to accurately obtain the number of rotations p required for the servo motor. Adjust the servo motor according to this number to adjust the ventilation rate to the required ventilation rate;

[0063] Step Four: After adjusting the ventilation rate of the thermal aging test equipment, automatically re-measure the ventilation rate, denoted by the symbol N cs , and end this self-calibration process after meeting the requirements. Update the ventilation rate data of all positions based on the ventilation rate data at this blade position combined with the initial calibration data. The specific method is (as Figure 3 shown): Use a long strip to represent the ventilation rate from 360° (fully enclosed) to 0° (fully open), where the small squares represent the ventilation rate changes corresponding to the minimum step value of the servo motor rotation. Calculate the difference X between the required ventilation rate N j and the initial ventilation rate at 0° (fully open), and the difference Y between the required ventilation rate N

[0064] X = N max - N j

[0065] Y = N j - N min ;

[0066] Determine the proportions of the ventilation rate difference X and the ventilation rate difference Y in all ventilation rate differences, that is

[0067] X / (N max - N min ) = k,

[0068] Y / (N max - N min ) = 1 - k;

[0069] Determine the proportions of the difference between the re-measured ventilation rate N cs and the initial ventilation rate at 0° (fully open) and the difference between the re-measured ventilation rate N max - N cs ) / (N max - N min ) and (N cs - N min ) / (N max - N min );

[0070] Determine the initial ventilation rate at 360° (fully enclosed) that needs to be adjusted to the re-measured ventilation rate N csThe proportionality coefficient a for this part, a·(N max -N cs ) / (N max -N min ) = k. Then, from the calculation, it can be known that a = (N j -N min ) / (N cs -N min );

[0071] Determine the re-measured ventilation rate N that needs to be adjusted cs The proportionality coefficient b for this part of the initial ventilation rate from 0° (fully open). b·(N max -N cs ) / (N max -N min ) = 1 - k. Then, from the calculation, it can be known that b = (N max -N j ) / (N max -N cs );

[0072] Update the calibrated initial ventilation rate at 360° (fully closed) to the re-measured ventilation rate N cs The change in the ventilation rate corresponding to the minimum step value of each rotation of the servo motor for this part, that is, multiply the change in the ventilation rate corresponding to the minimum step value of the initially calibrated servo motor rotation by the proportionality coefficient a;

[0073] Update the calibrated re-measured ventilation rate N cs The change in the ventilation rate corresponding to the minimum step value of each rotation of the servo motor for this part from the initial ventilation rate to 0° (fully open), that is, multiply the change value of the ventilation rate corresponding to the minimum step value of the initially calibrated servo motor rotation by the proportionality coefficient b;

[0074] Thus, the calibration of the ventilation rate at all positions of the servo motor rotation from 0 to M times is completed, which can ensure the long-term effectiveness of the algorithm.

[0075] Although the embodiments of the present invention have been shown and described above, it can be understood that the above embodiments are exemplary and should not be construed as limiting the present invention. Those of ordinary skill in the art can make changes, modifications, substitutions, and variations to the above embodiments within the scope of the present invention.

Claims

1. A self-calibrating air thermal aging test equipment, characterized in that: include: Self-calibration system, used to measure the temperature inside and outside the air thermal aging test equipment to obtain the working space temperature and ambient temperature of the test equipment, and to measure the heating power of the air thermal aging test equipment; The control system receives the data measured by the self-calibration system and calculates and processes the current actual temperature t of the air thermal aging test equipment. s 、Ambient temperature T p and the actual ventilation rate N k , with the actual temperature t s And the experimental temperature t m The difference is used as the temperature deviation to correct; the actual ventilation rate N k and the required ventilation rate N j The difference is sent to the self-calibration system as the ventilation rate deviation; The self-calibration system is used to compare the actual ventilation rate data with the actual required ventilation rate, control the servo motor to drive the ventilation fan blades of the air thermal aging test equipment to rotate, so as to adjust the ventilation rate of the thermal aging air test chamber, recalculate the actual ventilation rate, and update the ventilation rate data of all rotation positions of the servo motor to ensure the accuracy of subsequent ventilation rate adjustments.

2. The self-calibrating air thermal aging test equipment according to claim 1, characterized in that: The control system comprises: The temperature control module is used to receive the temperature deviation sent by the data processing module and automatically correct the temperature deviation of the air thermal aging test equipment; The data processing module is used to receive the data measured by the self-calibration system and calculate and process the current actual temperature t of the air thermal aging test equipment. s 、Ambient temperature T p and the actual ventilation rate N k ;: The actual ventilation rate N k Obtained by the following formula: Where h s is the coefficient, P1 is the average power when the air inlet is closed, P2 is the average power when the air inlet is open, c p is the specific heat capacity of air at normal pressure, V is the volume of the test equipment box, d is the ambient air density during the test, t1 is the ambient temperature, and T in degrees Kelvin is p Convert to Celsius to get; ambient temperature T p The calculation process is: The x ambient temperatures measured at equal intervals during the experimental time are used to obtain the quadratic fitting formula of the ambient temperature T by the least squares method, namely: T=b0+b1t+b2t 2 Among them, t is time, b0, b1, b2 are the quadratic coefficients of the ambient temperature changing with time. The quadratic coefficients are calculated by fitting the x ambient temperatures measured at equal intervals with the corresponding measurement time, and the temperature at each time point is obtained. The average temperature T of the ambient temperature values ​​obtained within the specified measurement time is calculated by the x ambient temperature values ​​measured within the specified measurement time and the curve equation obtained by fitting. p ,as follows: Among them, within the specified measurement time, that is, the time interval from time r1 to time r2; Current actual temperature t s The calculation process is: Where: n is the number of measurements at each temperature point, m is the number of measurement points, t ij It is the temperature value measured at the i-th measuring point for the jth time within the specified time.

3. The self-calibrating air thermal aging test equipment according to claim 2, characterized in that: The control system includes: air specific heat capacity and air density are calculated by using the average temperature obtained by the integral formula method: etc. p =a0+a1T p +a2T p 2 +a3T p 3 a0, a1, a2, a3 are coefficients related to the gas molecular formula and name, u is a constant; P is the standard atmospheric pressure.

4. The self-calibrating air thermal aging test equipment according to claim 1, characterized in that: The self-calibration system comprises: The automatic adjustment module is used to control the servo motor to drive the ventilation fan blades of the air thermal aging test equipment to rotate, so as to adjust the ventilation rate of the thermal aging air test chamber; The algorithm control module is used to compare the actual ventilation rate data with the actual required ventilation rate, calibrate the ventilation rate of the air thermal aging test equipment, and output it to the automatic adjustment module to dynamically adjust the ventilation rate of the thermal aging air test chamber.

5. The self-calibrating air thermal aging test equipment according to claim 4, characterized in that: The specific process of the algorithm control module calibrating the air exchange rate of the air thermal aging test equipment includes: Initial calibration records the ventilation rate data when the servo motor controls the fan blades to cover the ventilation holes at 0° and 360°. max and N min ; The servo motor is controlled to drive the fan blades on the air outlet of the air heat aging box to rotate to adjust the ventilation rate. The servo motor has a minimum step value i each time. The calibration records the ventilation rate corresponding to the minimum step value i of the servo motor control adjustment fan blade each time, that is, the calibration records the ventilation rate N corresponding to the angle of rotation m times. mi , and then get the ventilation rate difference between each step value; According to the ventilation rate of the ventilation fan blade at the current position automatically calculated after the start of self-calibration, determine whether it meets the required ventilation rate requirements based on the deviation between the ventilation rate at the current position and the required ventilation rate. If it does not meet the requirements, obtain the actual ventilation rate N corresponding to the current automatic adjustment angle ki of the servo motor k The ventilation rate N required by the user j Deviation Z, Z = N j -N k , combined with the ventilation fan blade located at the servo motor at the current k-time rotation position before and after the p-time rotation ventilation rate difference and the deviation Z are compared, the p-time ventilation rate difference before and after the current position is N (k±p)i -N k ; When Z = N j -N k >0, the servo motor rotates in the opposite direction to adjust the fan blade angle and increase the ventilation rate; when Z=N j -N k <0, the servo motor rotates forward to adjust the fan blade angle and reduce the ventilation rate; and the ventilation rate difference closest to the deviation Z is taken to obtain the number of rotations p required for the servo motor, and the servo motor is adjusted according to the number to adjust the ventilation rate to the required ventilation rate; After the ventilation rate of the air thermal aging test equipment is adjusted, the ventilation rate is automatically recalculated and the symbol N is used. cs , the self-calibration process ends after meeting the requirements, and the air change rate data of all positions are updated according to the air change rate data of the fan blade position combined with the initial calibration data.

6. The self-calibrating air thermal aging test equipment according to claim 5, characterized in that: The specific method for updating is: Calculate the required ventilation rate N j The difference between the initial ventilation rate at 0° and the initial ventilation rate at 360° is X, and the difference between the initial ventilation rate at 360° is Y: X=N max -N j Y=N j -N min ; Determine the proportion k and 1-k of the ventilation rate difference X and ventilation rate difference Y in the total ventilation rate difference, that is, X / (N max -N min )=k, Y / (N max -N min )=1-k; Determine the recalculated ventilation rate N cs The difference between the initial ventilation rate at 0° and the initial ventilation rate at 360° is the ratio of (N max -N cs ) / (N max -N min ) and (N cs -N min ) / (N max -N min ); Determine the 360° initial ventilation rate that needs to be adjusted to the recalculated ventilation rate N cs The proportional coefficient a of this part is: a=(N j -N min ) / (N cs -N min ); Determine the recalculated ventilation rate N that needs to be adjusted cs The proportionality factor b of the initial air change rate to 0° is: b=(N max -N j ) / (N max -N cs ); Update the calibration of the 360° initial air change rate to the recalculated air change rate N cs This part is the change in ventilation rate corresponding to the minimum step value of each servo motor rotation, that is, the change in ventilation rate corresponding to the initial calibrated minimum step value of the servo motor rotation multiplied by the proportional coefficient a; Update calibration and recalculate the ventilation rate N cs The change in ventilation rate corresponding to the minimum step value of each servo motor rotation from the initial ventilation rate to 0° is obtained by multiplying the ventilation rate change corresponding to the minimum step value of the servo motor rotation initially calibrated by the proportional coefficient b. This completes the update of the ventilation rate data of all positions of the servo motor rotating 0-M times.

7. The self-calibrating air thermal aging test equipment according to claim 1, characterized in that: The control system also includes an operation interface: an intuitive interface for providing a user with an operation control system, so as to set the temperature of the air thermal aging test equipment, control the calibration program, update parameters, and view the detection calibration results on the interface.

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