Temperature control method and system for fast temperature change test box

Abstract

The invention relates to the field of data processing, in particular to a rapid temperature change test box temperature control method and system, and the method comprises the steps: collecting the internal temperature and external temperature of a test box in real time; calculating the internal and external temperature change consistency of the local time period at the current moment; calculating a correction value of the internal temperature at the current moment by using the internal and external temperature change consistency; and presetting a gain parameter vector, calculating an adjustment value of the gain parameter vector at the current moment, inputting the adjustment value of the gain parameter vector at the current moment and an error between the correction value of the corresponding internal temperature and the target temperature in the test box into a PID controller, outputting a control signal, and performing temperature control on the test box according to the control signal. According to the invention, by adaptively adjusting the gain parameter, the overshoot caused by too fast system response speed and the oscillation phenomenon caused by the overshoot can be effectively avoided, so that the temperature change in the test box is more stable, and the stability of the temperature control process is ensured.

Description

Technical Field

[0001] The present invention relates to the field of data processing, and more specifically, to a temperature control method and system for a rapid temperature change test chamber. Background Art

[0002] The rapid temperature change test chamber is a device used to test the performance and reliability of products in a rapid temperature change environment. The rapid temperature change test chamber, also known as the rapid temperature change test chamber, plays a vital role in many fields such as material science, electronic products, automotive industry, aerospace, and communication equipment. It has the characteristics of high precision, high stability and high efficiency, and can simulate various rapid temperature change environments to evaluate the performance and durability of products under these conditions.

[0003] Prior art, such as a patent application document with publication number CN110716592A, discloses a temperature control method and related equipment, the temperature control method comprising: obtaining a current temperature and a preset temperature corresponding to a target position of an electronic device; determining a temperature difference corresponding to the target position based on the preset temperature and the current temperature, and then determining a function e(t) of the temperature difference with respect to time corresponding to the temperature difference, i.e., a target temperature difference function, according to a mapping relationship between a preset temperature difference and a preset temperature difference function; determining a target PID control parameter corresponding to a target application mode according to a mapping relationship between a preset application mode and a preset PID control parameter; and adjusting temperature and power consumption based on PID control.

[0004] However, the temperature adjustment based on PID control parameters in the above patent application documents mainly relies on preset PID parameters and target temperature difference functions, which cannot adapt to rapidly changing environmental conditions or changes in equipment status, resulting in reduced PID control performance and poor control effect. Summary of the invention

[0005] In order to solve the technical problem that the above-mentioned PID control has limitations, the present invention provides solutions in the following aspects.

[0006] In a first aspect, a temperature control method for a rapid temperature change test chamber includes: Collect the internal temperature and external temperature of the test box in real time; take the current moment as the starting point, intercept a set number of moments forward to construct a local time period of the current moment, and calculate the consistency of the internal and external temperature changes in the local time period; calculate the correction value of the internal temperature at the current moment using the consistency of the internal and external temperature changes; A gain parameter vector is preset, and the gain parameter vector includes a proportional gain, an integral gain, and a differential gain. An adjustment value of the gain parameter vector at the current moment is calculated, and the adjustment value of the gain parameter vector satisfies the relationship: ; In the formula, For the current moment The adjustment value of the gain parameter vector, is the preset gain parameter vector, For the current moment The corresponding adjustment factor is represents normalization processing; the adjustment factor is positively correlated with the rate of change of the internal temperature corresponding to the current moment, the correction value of the internal temperature at the current moment, and the difference between the target temperature inside the test chamber; The adjustment value of the gain parameter vector at the current moment, the corresponding correction value of the internal temperature and the error of the target temperature inside the test box are input into the PID controller, a control signal is output, and the temperature of the test box is controlled according to the control signal.

[0007] The present invention calculates the consistency of external temperature changes in a local time period and then obtains a correction value of the internal temperature, which can more accurately reflect the actual temperature conditions inside the test box, reduce the internal temperature measurement error caused by factors such as the external environment, and make temperature control more accurate; At the same time, the adjustment value of the gain parameter vector takes into account the rate of change of the internal temperature, the correction value, and the difference from the target temperature. It can dynamically adjust the proportional gain, integral gain, and differential gain according to the specific situation at the current moment, so that the parameters of the PID controller are more in line with actual needs and the accuracy of temperature control is further improved. Reasonable gain parameter adjustment can effectively avoid excessive overshoot caused by too fast system response speed and the resulting oscillation phenomenon, making the temperature change in the test chamber more stable and ensuring the stability of the temperature control process.

[0008] Preferably, the consistency of the internal and external temperature changes in the local time period satisfies the relationship: ; In the formula, For the current moment The consistency of external temperature changes within a local time period, For the current moment The maximum value of the difference between the internal temperature and the external temperature in the local time period, is the first The difference between the internal temperature and the external temperature at a certain moment, is the number of moments in the local time period, Represents an exponential function with the natural constant e as the base.

[0009] When the calculated If the value fluctuates abnormally or continues to decrease, it may indicate that the insulation performance of the test chamber has decreased, the external ambient temperature has changed dramatically, or other potential abnormal conditions. By using the temperature control value, these problems can be discovered in advance and corresponding measures can be taken in time to avoid test failure or equipment damage caused by temperature out of control and improve the reliability of temperature control.

[0010] Preferably, the correction value of the internal temperature at the current moment satisfies the relationship: ; In the formula, For the current moment The corresponding correction value of the internal temperature, For the current moment The corresponding internal temperature, For the current moment The first external temperature in the local time period, For the current moment The last external temperature during the local time period, For the current moment The consistency of external temperature changes within a local time period.

[0011] By correcting the internal temperature, the internal temperature fluctuation caused by external temperature changes can be reduced, making the internal temperature more stable. The correction relationship can adapt to different external environmental conditions. Even when the external temperature changes greatly, the internal temperature can be corrected to maintain the stability of the internal temperature, thereby improving the robustness of the temperature control system.

[0012] Preferably, the adjustment factor satisfies the relationship: ; In the formula, For the current moment The corresponding adjustment factor is For the current moment The corresponding rate of change of internal temperature, For the current moment The corresponding correction value of the internal temperature, is the preset internal target temperature.

[0013] The control strength is adjusted dynamically according to the rate of change and deviation of the internal temperature. When the rate of change is large or the deviation is large, the value of the adjustment factor will increase accordingly, thereby enhancing the output of the control signal, so that the temperature control system can more effectively adjust the internal temperature and quickly eliminate the deviation; conversely, when the rate of change and the deviation are small, the value of the adjustment factor is small, and the control strength is weakened accordingly, avoiding temperature fluctuations caused by excessive adjustment; when the external ambient temperature changes greatly or the internal temperature is disturbed, the adjustment factor can adjust the control parameters in time, reduce temperature mutations and oscillations, make the internal temperature change smoother, and improve the stability of temperature control.

[0014] Preferably, the current moment The corresponding rate of change of the internal temperature satisfies the relationship: ; In the formula, For the current moment The rate of change of the internal temperature, is the time variation, For the current moment Corrected value of the internal temperature, For the previous moment Correction value for the internal temperature.

[0015] Preferably, controlling the temperature of the test box according to the control signal comprises: When the control signal is positive, the heating power of the test chamber is increased to increase the internal temperature of the test chamber; When the control signal is negative, the cooling power of the test chamber is started to reduce the internal temperature of the test chamber.

[0016] Through precise temperature control and timely adjustment, the heating or cooling equipment can operate in a more reasonable working state, avoiding overheating or cooling caused by inaccurate temperature control, thereby reducing energy waste and lowering energy consumption.

[0017] Preferably, the adjustment factor satisfies the relationship: ; In the formula, For the current moment The corresponding adjustment factor is is a constant, For the current moment The corresponding rate of change of internal temperature, For the current moment The corresponding correction value of the internal temperature, is the preset internal target temperature.

[0018] In a second aspect, a temperature control system for a rapid temperature change test chamber includes: a processor and a memory, wherein the memory stores computer program instructions, and when the computer program instructions are executed by the processor, the above-mentioned temperature control method for the rapid temperature change test chamber is implemented.

[0019] The beneficial effects of the present invention are: The present invention significantly improves the accuracy, response speed and stability of temperature control by real-time acquisition and analysis of temperature data inside and outside the test chamber, combined with dynamic gain parameter adjustment and internal temperature correction strategy. By considering multiple factors such as external temperature influence, internal temperature change rate and target temperature difference, the present invention can flexibly adapt to different test environments and requirements, ensuring that the internal temperature of the test chamber can quickly and accurately reach and maintain within the preset target range. This not only improves the reliability and accuracy of the test, but also reduces the test error and failure risk caused by temperature fluctuations. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] By reading the following detailed description with reference to the accompanying drawings, the above and other objects, features and advantages of the exemplary embodiments of the present invention will become readily understood. In the accompanying drawings, several embodiments of the present invention are shown in an exemplary and non-limiting manner, and the same or corresponding reference numerals represent the same or corresponding parts, wherein: Figure 1 It is a method flow chart of steps S1 to S5 in a temperature control method for a rapid temperature change test chamber according to an embodiment of the present invention. DETAILED DESCRIPTION

[0021] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative work are within the scope of protection of the present invention.

[0022] The embodiment of the present invention discloses a temperature control method for a rapid temperature change test chamber, referring to Figure 1 , including steps S1 to S5, which are specifically as follows: S1: Collect the internal temperature and external temperature of the test box in real time.

[0023] High-precision temperature sensors, such as thermocouples and thermal resistors, are installed at key locations inside the rapid temperature change test chamber and outside the test chamber. These sensors can monitor the internal temperature of the test chamber and the external ambient temperature in real time.

[0024] The frequency of data collection is set to once every 5 seconds, and the total collection time is 1 hour.

[0025] S2: Taking the current moment as the starting point, intercept a set number of moments forward to construct a local time period of the current moment, and calculate the consistency of internal and external temperature changes in the local time period.

[0026] The test chamber maintains a stable internal temperature through its insulation layer and shell to simulate a specific test environment. The temperature inside the test chamber is maintained by its own heating or cooling system and is relatively independent of the external ambient temperature. In other words, under ideal conditions, changes in the external ambient temperature will not interfere with the temperature environment inside the test chamber.

[0027] However, when the insulation layer or shell of the test chamber is affected by external factors, heat may be lost from the inside of the test chamber or external heat may enter the test chamber, increasing the heat load and causing a deviation between the internally monitored temperature data and the actual temperature of the tested product. For example, when the test chamber is close to other heat-generating devices (such as air conditioners, etc.), the heat sources generated by these devices may cause additional heat load to the test chamber, resulting in excessively high external ambient temperatures.

[0028] Therefore, by observing the consistency between the internal temperature and the external temperature, we can preliminarily judge the thermal insulation performance of the test chamber and the impact of external environmental factors on the test results.

[0029] Specifically, a specific point is selected as the starting point in the above S1 time series, and then the starting point is traced back to several previous fixed time points, and then a time interval including the starting point and several previous moments is constructed as the local time period of the starting point.

[0030] The difference between the internal temperature and the external temperature at each moment in the local time period is further calculated, and the average value of the difference between the internal temperature and the external temperature at all moments in the local time period is calculated, and then the consistency of the external temperature change in the local time period is calculated.

[0031] Exemplarily, taking the current moment as the starting point, obtaining the internal temperature and external temperature including the current moment and some moments before the current moment (the first 9 moments), constructing the local time period of the current moment, the consistency of the external temperature change in the local time period satisfies the relationship:

[0032] In the formula, For the current moment The consistency of external temperature changes within a local time period, For the current moment The maximum value of the difference between the internal temperature and the external temperature in the local time period, is the first The difference between the internal temperature and the external temperature at a certain moment, is the number of moments in the local time period, Represents an exponential function with the natural constant e as the base.

[0033] like The value of is close to 1, indicating that in this local time period, the changes in the internal temperature and the external temperature are relatively consistent, which means that the shell material of the test chamber has a high thermal conductivity, or the insulation layer may be damaged, resulting in a significant impact of the external temperature on the internal temperature change; if If the value is low (close to 0), it means that the changes in the internal temperature are inconsistent with the external temperature. This may be because the test chamber has good thermal insulation performance, which makes the internal temperature relatively stable and not affected by external temperature changes.

[0034] S3: Calculate the correction value of the internal temperature at the current moment using the consistency of the internal and external temperature changes.

[0035] It should be noted that when the external temperature of the local time period in the above S2 increases as a whole, it means that the external environment temperature is rising. Since the thermal insulation performance of the test box is limited, it is impossible to completely isolate the impact of external temperature changes on the interior. The increase in external temperature will transfer part of the heat to the interior through the insulation layer of the test box, thereby causing the internal temperature of the test box to rise accordingly.

[0036] In this case, the internal temperature collected by the temperature sensor may be higher than the actual temperature. This is because the temperature measured by the temperature sensor is the temperature after being affected by the external temperature increase, while the actual temperature should be the temperature when it is not affected by the external temperature increase. In order to eliminate this measurement deviation caused by the external environment to a certain extent, it is necessary to correct the collected internal temperature to make it closer to the actual temperature.

[0037] Specifically, the first external temperature and the last external temperature in the local time period corresponding to the current moment are obtained respectively, the temperature difference between the first external temperature and the last external temperature is calculated, and the correction value of the internal temperature corresponding to the current moment is calculated in combination with the consistency of the internal and external temperature changes obtained in S2 above.

[0038] Then the correction value of the internal temperature corresponding to the current moment satisfies the relationship:

[0039] In the formula, For the current moment The corresponding correction value of the internal temperature, For the current moment The corresponding internal temperature, For the current moment The first external temperature in the local time period, For the current moment The last external temperature during the local time period, For the current moment The consistency of external temperature changes within a local time period.

[0040] When the external temperature rises and the consistency of the internal and external temperature changes is large, it means that the internal temperature at the current moment is greatly disturbed by external factors, so the internal temperature at the current moment needs to be reduced; conversely, if the external temperature decreases or the consistency of the internal and external temperature changes is small, there is no need or less need to adjust the internal temperature.

[0041] According to the calculation process of S2 and S3 above, the correction value of the internal temperature corresponding to each moment of real-time collection is calculated in the same way.

[0042] S4: Preset a gain parameter vector, where the gain parameter vector includes a proportional gain, an integral gain, and a differential gain, and calculate an adjustment value of the gain parameter vector at the current moment.

[0043] In the rapid temperature change test, the system needs to quickly and stably adjust the internal temperature to the preset target temperature. This process requires the system to have a high response speed and stability to ensure that the temperature can quickly and accurately reach the target value.

[0044] Traditional PID control algorithms adjust control devices to achieve target values ​​through fixed empirical gain parameters (i.e., proportional, integral, and differential gains) and real-time errors. However, these parameters are set based on past experience and may not be able to adapt to temperature changes at every moment. At different temperature stages, the system's requirements for control gain are different. Therefore, it is necessary to adaptively adjust the gain parameters according to the real-time temperature changes so that the test chamber can respond faster when temperature control begins and quickly approach the target temperature; at the same time, when the temperature approaches the target value, avoid exceeding the target temperature too much (overadjustment) or the temperature repeatedly fluctuates up and down (oscillation) near the target value, thereby ensuring that the temperature inside the test chamber can quickly and stably reach the set target temperature.

[0045] Specifically, first, the change amount of the correction value of the internal temperature corresponding to the current moment and the time change amount are calculated, and the ratio of the change amount of the temperature correction value to the time change amount is taken as the change rate of the internal temperature at the current moment, that is, the relationship is satisfied:

[0046] In the formula, For the current moment The rate of change of the internal temperature, For the current moment With the previous moment The change in the correction value of the internal temperature, is the time variation, For the current moment Corrected value of the internal temperature, For the previous moment Correction value for the internal temperature.

[0047] Then, calculate the error between the corrected value of the current internal temperature and the target temperature (i.e. the specific temperature value to be reached and maintained inside the test chamber, which is set artificially. This temperature value is determined based on the specific requirements, standards or specifications of the test or test to ensure the accuracy and comparability of the test or test results).

[0048] Next, we empirically set the gain parameter vector , Including proportional gain, integral gain and differential gain, calculate the gain parameter vector The adjustment value satisfies the relationship:

[0049] In the formula, For the current moment The adjustment value of the gain parameter vector, is the preset gain parameter vector, For the current moment The corresponding adjustment factor is Indicates normalization processing.

[0050] in, The relationship is satisfied:

[0051] In the formula, For the current moment The corresponding adjustment factor is For the current moment The corresponding rate of change of internal temperature, For the current moment The corresponding correction value of the internal temperature, is the preset internal target temperature.

[0052] When the temperature change rate is small and the error is also small, it means that the system is close to the target temperature. At this time, the gain parameter needs to be reduced to avoid instability caused by over-adjustment. On the contrary, when the temperature change rate is large or the error is large, it means that the system may still be far from the target temperature. At this time, the gain parameter needs to be increased to speed up the system response.

[0053] In another embodiment, the above adjustment factor also satisfies the relationship:

[0054] In the formula, For the current moment The corresponding adjustment factor is is a constant, For the current moment The corresponding rate of change of internal temperature, For the current moment The corresponding correction value of the internal temperature, is the preset internal target temperature.

[0055] Exemplarily, updating the proportional gain parameter The relationship is satisfied:

[0056] In the formula, is the proportional gain parameter adjustment value.

[0057] Update the proportional gain parameters according to the above Similarly, the adjustment values ​​corresponding to the integral gain and differential gain are obtained.

[0058] S5: Input the adjustment value of the gain parameter vector at the current moment, the corresponding correction value of the internal temperature, and the error of the target temperature inside the test box into the PID controller, output a control signal, and control the temperature of the test box according to the control signal.

[0059] The adjustment value of the gain parameter vector at the current moment obtained in S4 above, the corresponding correction value of the internal temperature, and the error of the target temperature are input into the PID controller, and a control signal is calculated and output according to the internal control algorithm.

[0060] When the control signal is positive, the heating power of the test chamber is increased to increase the internal temperature of the test chamber; when the control signal is negative, the cooling power of the test chamber is started to reduce the internal temperature of the test chamber.

[0061] According to the calculation process of S2-S5 above, the adjustment value of each parameter in the gain parameter vector at each moment obtained in real time, as well as the error between the corrected value of the internal temperature of the system at that moment and the set target temperature, can be sent to the PID controller as an input signal.

[0062] The whole process is a dynamic closed-loop control process. By continuously acquiring the gain parameter vector and temperature error in real time, calculating the control signal, and adjusting the working state of the heating or cooling equipment accordingly, the system temperature can be precisely controlled to stabilize it near the target temperature.

[0063] The embodiment of the present invention further discloses a temperature control system for a rapid temperature change test chamber, including a processor and a memory, wherein the memory stores computer program instructions, and when the computer program instructions are executed by the processor, a temperature control method for a rapid temperature change test chamber according to the present invention is implemented.

[0064] The system also includes other components familiar to those skilled in the art, such as a communication bus and a communication interface. The configuration and functions of these components are known in the art and will not be described in detail here.

[0065] In the present invention, the aforementioned memory may be any tangible medium containing or storing a program, which may be used by or in combination with an instruction execution system, apparatus or device. For example, a computer-readable storage medium may be any appropriate magnetic storage medium or magneto-optical storage medium, such as a resistive random access memory RRAM (Resistive Random Access Memory), a dynamic random access memory DRAM (Dynamic Random Access Memory), a static random access memory SRAM (Static Random-Access Memory), an enhanced dynamic random access memory EDRAM (Enhanced Dynamic Random Access Memory), a high-bandwidth memory HBM (High-Bandwidth Memory), a hybrid memory cube HMC (Hybrid Memory Cube), etc., or any other medium that can be used to store the required information and can be accessed by an application, a module or both. Any such computer storage medium may be part of a device or accessible or connectable to a device.

[0066] In the description of this specification, "plurality" or "several" means at least two, such as two, three or more, etc., unless otherwise clearly and specifically defined.

[0067] Although this specification has shown and described a number of embodiments of the present invention, it will be apparent to those skilled in the art that such embodiments are provided by way of example only. Those skilled in the art will conceive of many modifications, changes and alternatives without departing from the ideas and spirit of the present invention. It should be understood that in the practice of the present invention, various alternatives to the embodiments of the present invention described herein may be employed.

Claims

1. A temperature control method for a rapid temperature change test chamber, characterized in that: include: Collect the internal temperature and external temperature of the test box in real time; take the current moment as the starting point, intercept a set number of moments forward to construct a local time period of the current moment, and calculate the consistency of the internal and external temperature changes in the local time period; calculate the correction value of the internal temperature at the current moment using the consistency of the internal and external temperature changes; A gain parameter vector is preset, and the gain parameter vector includes a proportional gain, an integral gain, and a differential gain. An adjustment value of the gain parameter vector at the current moment is calculated, and the adjustment value of the gain parameter vector satisfies the relationship: ; In the formula, For the current moment The adjustment value of the gain parameter vector, is the preset gain parameter vector, For the current moment The corresponding adjustment factor is represents normalization processing; the adjustment factor is positively correlated with the rate of change of the internal temperature corresponding to the current moment, the correction value of the internal temperature at the current moment, and the difference between the target temperature inside the test chamber; The adjustment value of the gain parameter vector at the current moment, the corresponding correction value of the internal temperature and the error of the target temperature inside the test box are input into the PID controller, a control signal is output, and the temperature of the test box is controlled according to the control signal.

2. A temperature control method for a rapid temperature change test chamber according to claim 1, characterized in that: The consistency of the internal and external temperature changes in the local time period satisfies the relationship: ; In the formula, For the current moment The consistency of external temperature changes within a local time period, For the current moment The maximum value of the difference between the internal temperature and the external temperature in the local time period, is the first The difference between the internal temperature and the external temperature at a certain moment, is the number of moments in the local time period, Represents an exponential function with the natural constant e as the base.

3. A temperature control method for a rapid temperature change test chamber according to claim 2, characterized in that: The correction value of the internal temperature at the current moment satisfies the relationship: ; In the formula, For the current moment The corresponding correction value of the internal temperature, For the current moment The corresponding internal temperature, For the current moment The first external temperature in the local time period, For the current moment The last external temperature during the local time period, For the current moment The consistency of external temperature changes within a local time period.

4. A temperature control method for a rapid temperature change test chamber according to claim 3, characterized in that: The adjustment factor satisfies the relationship: ; In the formula, For the current moment The corresponding adjustment factor is For the current moment The corresponding rate of change of internal temperature, For the current moment The corresponding correction value of the internal temperature, is the preset internal target temperature.

5. A temperature control method for a rapid temperature change test chamber according to claim 4, characterized in that: Current moment The corresponding rate of change of the internal temperature satisfies the relationship: ; In the formula, For the current moment The rate of change of the internal temperature, is the time variation, For the current moment Corrected value of the internal temperature, For the previous moment Correction value for the internal temperature.

6. A temperature control method for a rapid temperature change test chamber according to claim 5, characterized in that: The temperature control of the test chamber according to the control signal includes: When the control signal is positive, the heating power of the test chamber is increased to increase the internal temperature of the test chamber; When the control signal is negative, the cooling power of the test chamber is started to reduce the internal temperature of the test chamber.

7. A temperature control method for a rapid temperature change test chamber according to claim 3, characterized in that: The adjustment factor satisfies the relationship: ; In the formula, For the current moment The corresponding adjustment factor is is a constant, For the current moment The corresponding rate of change of internal temperature, For the current moment The corresponding correction value of the internal temperature, is the preset internal target temperature.

8. A temperature control system for a rapid temperature change test chamber, characterized in that: include: A processor and a memory, wherein the memory stores computer program instructions, and when the computer program instructions are executed by the processor, the temperature control method for a rapid temperature change test chamber according to any one of claims 1 to 7 is implemented.

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