Constant temperature and humidity chamber control method

Abstract

The invention relates to the technical field of constant-temperature and constant-humidity chambers, in particular to a constant-temperature and constant-humidity chamber control method which comprises the following steps: S1, designing a constant-temperature and constant-humidity system, and controlling mode conversion by changing the polarity of current based on the Peltier effect, the modes including refrigeration and heating; when the constant temperature and humidity control device is used, compared with a traditional constant temperature and humidity product, parts are saved, the cost is saved, the humidification and dehumidification speed and the humidification and dehumidification strength are dynamically adjusted according to humidity data changes, the fluctuation stability of the humidity within a preset range is improved, a control strategy is optimized, and the humidity control device is suitable for popularization and application. And the temperature difference within + / -0.5 DEG C is considered to be stable. The temperature control accuracy is improved, excessive adjustment and energy waste are avoided, when the target temperature and humidity are approached, low power is selected to adjust non-key equipment, the effects of saving energy and improving system stability are achieved, and the adaptability, efficiency and reliability of the constant temperature and humidity system are improved.

Description

Technical Field

[0001] The invention relates to the technical field of constant temperature and humidity chambers, and in particular to a constant temperature and humidity chamber control method. Background Art

[0002] Constant temperature and humidity chamber is a kind of laboratory equipment used to control temperature and humidity conditions, which is widely used in scientific research, production and manufacturing, quality inspection and other fields. It can provide a stable and adjustable environment to meet the strict requirements of temperature and humidity for different experiments or tests.

[0003] The patent application number is CN202210479014.0, which states in the specification that "This application relates to the technical field of constant temperature and humidity chambers, and discloses a method for controlling a constant temperature and humidity chamber, including: obtaining the temperature inside the constant temperature and humidity chamber; when the temperature inside the chamber meets the steady-state condition, determining the target speed value according to the current speed value of the external fan; adjusting the speed value of the external fan to the target speed value. Whether the current operation of the constant temperature and humidity chamber is stable is judged by the temperature change in the constant temperature and humidity chamber. When it is determined that the constant temperature and humidity chamber is operating stably, the speed of the external fan is adjusted to reduce noise. Specifically, according to the current speed value of the external fan, it is determined that it will not affect The target speed value for the stable operation of the constant temperature and humidity chamber. Therefore, while ensuring the steady-state operation of the constant temperature and humidity chamber, the noise can be reduced by adjusting the speed of the external fan. There is no need to reduce the failure rate of the constant temperature and humidity chamber by adding a new noise reduction device. The present application also discloses a device for controlling a constant temperature and humidity chamber, a constant temperature and humidity chamber, and a storage medium. Although the above technology can reduce noise, increase the service life of the equipment and reduce the failure rate while ensuring the steady-state operation of the constant temperature and humidity chamber by accurately controlling the speed of the external fan, during the operation of the above technology, the temperature and humidity control system often requires multiple hardware to work simultaneously, resulting in high power consumption, which is not conducive to energy saving.

[0004] In summary, developing a constant temperature and humidity chamber control method is still a key issue that needs to be urgently addressed in the field of constant temperature and humidity chamber technology. Summary of the invention

[0005] The purpose of the present invention is to solve the problem in the prior art that although the above-mentioned technology can reduce noise, increase the service life of the equipment and reduce the failure rate while ensuring the steady-state operation of the constant temperature and humidity chamber by accurately controlling the speed of the external fan, during the operation of the above-mentioned technology, the temperature and humidity control system often requires multiple hardware to work simultaneously, resulting in high power consumption and not conducive to energy saving.

[0006] To achieve the above object, the present invention provides the following technical solutions:

[0007] The present invention provides a constant temperature and humidity chamber control method, comprising the following steps: S1, designing a constant temperature and humidity system, and controlling mode conversion by changing the polarity of current based on the Peltier effect, wherein the modes include cooling and heating;

[0008] S2, collect temperature and humidity data inside the constant temperature and humidity chamber through sensors, and monitor the changes of temperature and humidity in cooling mode and heating mode in real time;

[0009] S3. According to the changes in humidity data, the constant temperature and humidity system is controlled to perform corresponding dehumidification and humidification work;

[0010] S4, adjusting the temperature inside the constant temperature and humidity chamber by controlling the direction of the current according to the preset temperature conditions of the constant temperature and humidity chamber;

[0011] S5. Perform intelligent analysis and optimization based on changes in temperature and humidity data during adjustment.

[0012] Further, in step S1, a constant temperature and humidity system is designed, and the mode conversion is controlled by changing the polarity of the current based on the Peltier effect. The modes include cooling and heating. The method is as follows:

[0013] The refrigeration compressor, evaporator and air heater in the traditional constant temperature and humidity products are replaced by semiconductor refrigerators, and the dehumidifier and water tank heater are replaced by water-cooled semiconductor refrigerators. Two conductors of different materials are connected to form a thermocouple. The Peltier effect relies on the fact that when the current passes through the two semiconductors of different materials, the cold end of the thermocouple absorbs heat and the hot end releases heat, thereby achieving temperature regulation. By reversing the direction of the current, the functions of the cold end and the hot end are interchanged, so that the two modes of cooling and heating can be achieved. The Peltier effect and temperature regulation formula are: Where Z represents the total thermal effect caused by the current and temperature difference, is the thermoelectric coefficient, β is the thermal conductivity, ΔT is the temperature difference between the two ends, I is the current intensity, and ΔT 2 is the square of the temperature difference, C VB is the DC voltage, X thermo is the thermal resistance of the semiconductor, It represents the amount of heat transferred per unit time.

[0014] Further, in step S2, the method of collecting temperature data and humidity data inside the constant temperature and humidity chamber through sensors and monitoring the changes of temperature and humidity in the cooling mode and the heating mode in real time is:

[0015] Data is collected through sensors, including PT100 temperature sensor and DHT22 humidity sensor. The collected temperature data and humidity data are processed in real time by Arduino microcontroller. The temperature data and humidity data are calibrated and filtered. The temperature and humidity changes in the box are monitored according to the temperature data and humidity data. The target temperature is N target , the target humidity is M target , filtering processing formula: Where α is the time constant of the filter, s is the Laplace transform variable, and A(s) is the transfer function of the system.

[0016] Further, in step S2, the method of collecting temperature data and humidity data inside the constant temperature and humidity chamber through sensors and monitoring the changes of temperature and humidity in the cooling mode and the heating mode in real time is:

[0017] Determine whether to switch the working mode according to the changes in temperature and humidity. In cooling mode, the temperature gradually decreases and the humidity increases. In heating mode, the temperature increases and the humidity decreases. Real-time temperature and humidity data are transmitted through any communication protocol such as UART, I2C or SPI for real-time monitoring and adjustment. The judgment formula is: Where ΔN represents the current temperature N current With target temperature N target The difference between the two, ΔM represents the current humidity M current and target humidity M target The difference between N And ΔM>∈ M Switch working mode when N is the threshold of temperature deviation, ∈ M is the humidity deviation threshold.

[0018] Further, in step S3, according to the high and low changes of humidity data, the method of controlling the constant temperature and humidity system to perform corresponding dehumidification and humidification is:

[0019] The user sets the upper and lower humidity thresholds by himself. When the humidity is lower than 40%RH, the humidification operation is started, and when it exceeds 70%RH, the dehumidification operation is started. During the dehumidification process, the water-cooled semiconductor refrigerator uses the Peltier effect to reduce the cold end temperature to below the air dew point temperature, thereby achieving water vapor condensation. During humidification, the water in the humidification tank in the constant temperature and humidity chamber is heated by changing the DC voltage polarity of the water-cooled semiconductor refrigerator. After the water temperature rises, the water vapor evaporates to achieve the purpose of humidification. The humidity change formula is:

[0020] in is the ratio of the temperature change rate to the humidity change rate, χ represents the linear influence of humidity change on temperature adjustment, δ represents the influence of temperature difference change on humidity adjustment, N dew Indicates the temperature at which water vapor in the air begins to condense. The humidity threshold control formula is: Among them, M current Represents the current humidity value, G′ means the dehumidification mode is activated, and G″ means the humidification mode is activated.

[0021] Further, in step S3, according to the high and low changes of humidity data, the method of controlling the constant temperature and humidity system to perform corresponding dehumidification and humidification is:

[0022] The dehumidification process and the humidification process are subject to real-time feedback from sensors, and the operation intensity is dynamically adjusted according to the actual humidity changes. At the same time, the humidification and dehumidification rates are adjusted, and temperature protection and humidity protection are implemented. The humidity data and operation logs are recorded, and the humidity control strategy is analyzed and optimized, and the formula is dynamically adjusted. in is the mass flow rate of moisture during the humidification process, is a function of the humidification process, ∈ M′ is the humidification efficiency, ΔN current is the current temperature difference, is the cooling power, is the mass flow rate of moisture during the dehumidification process, is a function of the dehumidification process, is the dehumidification efficiency, ΔN current is the current temperature difference, is the heating power.

[0023] Further, in step S4, according to the preset temperature condition of the constant temperature and humidity chamber, the method of adjusting the temperature inside the constant temperature and humidity chamber by controlling the direction of the current is:

[0024] The temperature data collected from the constant temperature and humidity chamber in real time by the PT100 temperature sensor is compared with the target temperature preset by the user. By calculating the temperature difference, it is determined whether the current direction needs to be adjusted to perform any of the heating or cooling operations. The PID control algorithm is used to smoothly adjust the temperature, and closed-loop control is performed by real-time monitoring of temperature data. When the temperature is higher than the target temperature preset by the user, the cooling mode is started; when the temperature is lower than the target temperature preset by the user, the current direction is adjusted in the opposite direction to start the heating mode. The expression of the PID control algorithm is: Where u(t′) is the control output, e(t′) is the error, K p is the proportional gain, K i is the integral gain, K d′ is the differential gain, is the integral of the error, is the derivative of the error.

[0025] Further, in step S4, according to the preset temperature condition of the constant temperature and humidity chamber, the method of adjusting the temperature inside the constant temperature and humidity chamber by controlling the direction of the current is:

[0026] Optimize response time and balance reaction strength by dynamically adjusting PID parameter model. If the temperature difference is less than the tolerance range of ±0.5℃, the temperature is considered stable. At the same time, over-temperature and low-temperature protection mechanisms are set, and PID parameters are optimized through adaptive algorithms. The control strategy is dynamically adjusted according to past temperature data, and the PID parameter model expression is dynamically adjusted: Where K p (t′) is a time-dependent function, is the reference value of the proportional gain, is the adjustment coefficient of proportional gain as the error changes, e(t′) is the current error, K i (t′) is the dynamically changing integral gain, is the reference value of the integral gain, is a coefficient controlling the effect of the error integral on the gain, represents the error integral from the start time to the current time t′, K d′ (t′) is the dynamically changing differential gain, is the reference value of the differential gain, is the differential gain adjustment coefficient, is the rate of change of error.

[0027] Further, in step S5, the method for performing intelligent analysis and optimization according to the changes of temperature data and humidity data during adjustment is:

[0028] By calculating the difference between the temperature data and humidity data and the target value, any one of the working modes of heating, cooling, humidification or dehumidification is intelligently selected. When the temperature data exceeds the user's preset target value, any one of the working modes of cooling or heating is selected to start according to the humidity data. At the same time, whether to start any one of the working modes of humidification or dehumidification is determined according to the error of the user's preset target value of the humidity data. When the temperature data and humidity data fluctuate at the same time, a balanced control strategy is adopted to achieve synchronous adjustment of the heating, cooling, humidification and dehumidification modes. The intelligent selection formula is: Where L(t″) is the state vector at time t″, L(t″+1) is the state at the next time t″+1, Q is the matrix of the linear relationship from the current state to the next state, W is the control matrix, and φ(t″) is the control input vector at time t″.

[0029] Further, in step S5, the method for performing intelligent analysis and optimization according to the changes of temperature data and humidity data during adjustment is:

[0030] The PID control algorithm is used to combine the proportional, integral and differential terms to adjust the working mode in real time. At the same time, the control strategy is optimized through adaptive adjustment and machine learning algorithms to continuously learn the fluctuation patterns of temperature and humidity data. In addition, intelligent decision-making is made through fuzzy control to handle the temperature and humidity adjustment requirements under uncertain and complex situations. The temperature and humidity adjustment process is coordinated through temperature and humidity coupling control. When the temperature and humidity are close to the user's preset target temperature and humidity, low power adjustment of non-critical equipment is selected. The expression formula of fuzzy control and intelligent decision-making is: where γ N (∈N) is the fuzzy membership function of temperature error, γ M (∈M) is the fuzzy membership function of humidity error.

[0031] Beneficial Effects

[0032] Compared with the known public technology, the technical solution provided by the present invention has the following advantages:

[0033] Beneficial effects:

[0034] When used, the present invention saves parts and components compared with traditional constant temperature and humidity products, which is conducive to cost saving. It dynamically adjusts the rate of humidification and dehumidification and adjusts the intensity of humidification and dehumidification according to the change of humidity data, which is conducive to improving the stability of humidity fluctuations within a preset range, optimizing the control strategy, and ensuring that the temperature difference is considered stable within ±0.5°C. It is not only conducive to improving the accuracy of temperature control, but also avoids over-adjustment and energy waste. When approaching the target temperature and humidity, low power adjustment of non-critical equipment is selected to achieve the effect of energy saving and improving system stability, which is conducive to improving the adaptability, efficiency and reliability of the constant temperature and humidity system. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] Figure 1 The present invention is a flow chart of a method for controlling a constant temperature and humidity chamber. DETAILED DESCRIPTION

[0036] In order to enable those skilled in the art to better understand the scheme of the present invention, the technical scheme in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only 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 ordinary technicians in this field without creative work should fall within the scope of protection of the present invention.

[0037] It should be noted that the terms "first", "second", etc. in the specification and claims of the present invention and the above-mentioned drawings are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence. It should be understood that the data used in this way can be interchanged where appropriate, so that the embodiments of the present invention described herein can be implemented in an order other than those illustrated or described herein. In addition, the terms "including" and "having" and any variations thereof are intended to cover non-exclusive inclusions, for example, a process, method, system, product or device that includes a series of steps or units is not necessarily limited to those steps or units clearly listed, but includes other steps or units that are not clearly listed or inherent to these processes, methods, products or devices.

[0038] The present invention is further described in detail below in conjunction with the accompanying drawings:

[0039] Example:

[0040] like Figure 1 As shown, the present invention provides a constant temperature and humidity chamber control method, comprising the following steps: S1, designing a constant temperature and humidity system, and controlling mode conversion by changing the polarity of current based on the Peltier effect, wherein the modes include cooling and heating;

[0041] Further, in step S1, in step S1, a constant temperature and humidity system is designed, and the mode conversion is controlled by changing the polarity of the current based on the Peltier effect, and the mode includes cooling and heating methods as follows:

[0042] The refrigeration compressor, evaporator and air heater in the traditional constant temperature and humidity products are replaced by semiconductor refrigerators, and the dehumidifier and water tank heater are replaced by water-cooled semiconductor refrigerators. Two conductors of different materials are connected to form a thermocouple. The Peltier effect relies on the fact that when the current passes through the two semiconductors of different materials, the cold end of the thermocouple absorbs heat and the hot end releases heat, thereby achieving temperature regulation. By reversing the direction of the current, the functions of the cold end and the hot end are interchanged, so that the two modes of cooling and heating can be achieved. The Peltier effect and temperature regulation formula are: Where Z represents the total thermal effect caused by the current and temperature difference, is the thermoelectric coefficient, β is the thermal conductivity, ΔT is the temperature difference between the two ends, I is the current intensity, and ΔT 2 is the square of the temperature difference, C VB is the DC voltage, X thermo is the thermal resistance of the semiconductor, It represents the amount of heat transferred per unit time;

[0043] In this embodiment, the refrigeration compressor, evaporator and air heater in the traditional constant temperature and humidity products are replaced by semiconductor refrigerators, and the dehumidifier and water tank heater are replaced by water-cooled semiconductor refrigerators, water pumps, humidification water tanks and other hardware components. Compared with traditional constant temperature and humidity products, it saves parts. The Peltier effect realizes cooling or heating based on the thermal effect when current passes through semiconductors of different materials. When current flows through semiconductor materials, heat is absorbed at the cold end and heat is released at the hot end. The change in temperature difference allows the temperature to be adjusted, which is not only conducive to optimizing energy efficiency, but also improves the response speed and accuracy of the equipment, with lower energy consumption and higher control flexibility.

[0044] S2, collect temperature and humidity data inside the constant temperature and humidity chamber through sensors, and monitor the changes of temperature and humidity in cooling mode and heating mode in real time;

[0045] Further, in step S2, the method of collecting temperature data and humidity data inside the constant temperature and humidity chamber through sensors and monitoring the changes of temperature and humidity in the cooling mode and the heating mode in real time is:

[0046] Data is collected through sensors, including PT100 temperature sensor and DHT22 humidity sensor. The collected temperature data and humidity data are processed in real time by Arduino microcontroller. The temperature data and humidity data are calibrated and filtered. The temperature and humidity changes in the box are monitored according to the temperature data and humidity data. The target temperature is N target , the target humidity is M target , filtering processing formula: Where α is the time constant of the filter, s is the Laplace transform variable, and A(s) is the transfer function of the system.

[0047] Further, in step S2, the method of collecting temperature data and humidity data inside the constant temperature and humidity chamber through sensors and monitoring the changes of temperature and humidity in the cooling mode and the heating mode in real time is:

[0048] Determine whether to switch the working mode according to the changes in temperature and humidity. In cooling mode, the temperature gradually decreases and the humidity increases. In heating mode, the temperature increases and the humidity decreases. Real-time temperature and humidity data are transmitted through any communication protocol such as UART, I2C or SPI for real-time monitoring and adjustment. The judgment formula is: Where ΔN represents the current temperature N current With target temperature N target The difference between the two, ΔM represents the current humidity M current and target humidity M target The difference between N And ΔM>∈ M Switch working mode whenN is the threshold of temperature deviation, ∈ M is the threshold of humidity deviation;

[0049] In this embodiment, the collected temperature and humidity data are processed in real time by a microcontroller, and calibrated and filtered to ensure the accuracy of the data. Filtering helps to reduce the impact of noise, making the monitoring of temperature and humidity changes more accurate. The working mode is switched according to the temperature and humidity changes. When the temperature and humidity data deviate from the preset target, the system transmits data in real time through the communication protocol, switches and adjusts the mode, thereby ensuring that the temperature and humidity remain within the preset range, which is conducive to improving the accuracy of temperature and humidity control, optimizing the heating and cooling process, and improving the energy efficiency and response speed of the equipment.

[0050] S3. According to the changes in humidity data, the constant temperature and humidity system is controlled to perform corresponding dehumidification and humidification work;

[0051] Further, in step S3, according to the high and low changes of humidity data, the method of controlling the constant temperature and humidity system to perform corresponding dehumidification and humidification is:

[0052] The user sets the upper and lower humidity thresholds by himself. When the humidity is lower than 40%RH, the humidification operation is started, and when it exceeds 70%RH, the dehumidification operation is started. During the dehumidification process, the water-cooled semiconductor refrigerator uses the Peltier effect to reduce the cold end temperature to below the air dew point temperature, thereby achieving water vapor condensation. During humidification, the water in the humidification tank in the constant temperature and humidity chamber is heated by changing the DC voltage polarity of the water-cooled semiconductor refrigerator. After the water temperature rises, the water vapor evaporates to achieve the purpose of humidification. The humidity change formula is:

[0053] in is the ratio of the temperature change rate to the humidity change rate, χ represents the linear influence of humidity change on temperature adjustment, δ represents the influence of temperature difference change on humidity adjustment, N dew Indicates the temperature at which water vapor in the air begins to condense. The humidity threshold control formula is: Among them, M current Represents the current humidity value, G′ means the dehumidification mode is activated, and G″ means the humidification mode is activated.

[0054] Further, in step S3, according to the high and low changes of humidity data, the method of controlling the constant temperature and humidity system to perform corresponding dehumidification and humidification is:

[0055] The dehumidification process and the humidification process are subject to real-time feedback from sensors, and the operation intensity is dynamically adjusted according to the actual humidity changes. At the same time, the humidification and dehumidification rates are adjusted, and temperature protection and humidity protection are implemented. The humidity data and operation logs are recorded, and the humidity control strategy is analyzed and optimized, and the formula is dynamically adjusted. in is the mass flow rate of moisture during the humidification process, is a function of the humidification process, ∈ M′ is the humidification efficiency, ΔN current is the current temperature difference, is the cooling power, is the mass flow rate of moisture during the dehumidification process, is a function of the dehumidification process, is the dehumidification efficiency, ΔN current is the current temperature difference, is the heating power;

[0056] In this embodiment, the user can set the upper and lower limit thresholds of humidity. When the humidity is lower than 40%RH, the humidification operation is started; when the humidity exceeds 70%RH, the dehumidification operation is started. The humidity control process is subject to real-time feedback from the sensor. The rate and intensity of humidification and dehumidification are dynamically adjusted according to the changes in humidity data. This not only helps to improve the stability of humidity fluctuations within the preset range, but also improves the response speed through intelligent adjustment to avoid excessive humidification or dehumidification.

[0057] S4, adjusting the temperature inside the constant temperature and humidity chamber by controlling the direction of the current according to the preset temperature conditions of the constant temperature and humidity chamber;

[0058] Further, in step S4, according to the preset temperature condition of the constant temperature and humidity chamber, the method of adjusting the temperature inside the constant temperature and humidity chamber by controlling the direction of the current is:

[0059] The temperature data collected from the constant temperature and humidity chamber in real time by the PT100 temperature sensor is compared with the target temperature preset by the user. By calculating the temperature difference, it is determined whether the current direction needs to be adjusted to perform any of the heating or cooling operations. The PID control algorithm is used to smoothly adjust the temperature, and closed-loop control is performed by real-time monitoring of temperature data. When the temperature is higher than the target temperature preset by the user, the cooling mode is started; when the temperature is lower than the target temperature preset by the user, the current direction is adjusted in the opposite direction to start the heating mode. The expression of the PID control algorithm is: Where u(t′) is the control output, e(t′) is the error, K p is the proportional gain, K i is the integral gain, K d′ is the differential gain, is the integral of the error, is the derivative of the error.

[0060] Further, in step S4, according to the preset temperature condition of the constant temperature and humidity chamber, the method of adjusting the temperature inside the constant temperature and humidity chamber by controlling the direction of the current is:

[0061] Optimize response time and balance reaction strength by dynamically adjusting PID parameter model. If the temperature difference is less than the tolerance range of ±0.5℃, the temperature is considered stable. At the same time, over-temperature and low-temperature protection mechanisms are set, and PID parameters are optimized through adaptive algorithms. The control strategy is dynamically adjusted according to past temperature data, and the PID parameter model expression is dynamically adjusted: Where K p (t′) is a time-dependent function, is the reference value of the proportional gain, is the adjustment coefficient of proportional gain as the error changes, e(t′) is the current error, K i (t′) is the dynamically changing integral gain, is the reference value of the integral gain, is a coefficient controlling the effect of the error integral on the gain, represents the error integral from the start time to the current time t′, K d′ (t′) is the dynamically changing differential gain, is the reference value of the differential gain, is the differential gain adjustment coefficient, is the rate of change of error;

[0062] In this embodiment, it is determined whether the current direction needs to be adjusted according to the temperature difference to start the heating or cooling mode. By real-time monitoring of temperature data, a closed-loop control strategy is adopted. When the temperature is higher than the target temperature, the cooling mode is started, and when the temperature is lower than the target, the current direction is reversed to start the heating mode. The control strategy is optimized by dynamically adjusting the PID parameters to ensure that the temperature difference is considered stable within ±0.5°C. This not only helps to improve the accuracy of temperature control, but also avoids over-adjustment and energy waste.

[0063] S5. Perform intelligent analysis and optimization based on the changes in temperature data and humidity data during adjustment;

[0064] Further, in step S5, the method for performing intelligent analysis and optimization according to the changes of temperature data and humidity data during adjustment is:

[0065] By calculating the difference between the temperature data and humidity data and the target value, any one of the working modes of heating, cooling, humidification or dehumidification is intelligently selected. When the temperature data exceeds the user's preset target value, any one of the working modes of cooling or heating is selected to start according to the humidity data. At the same time, whether to start any one of the working modes of humidification or dehumidification is determined according to the error of the user's preset target value of the humidity data. When the temperature data and humidity data fluctuate at the same time, a balanced control strategy is adopted to achieve synchronous adjustment of the heating, cooling, humidification and dehumidification modes. The intelligent selection formula is: Where L(t″) is the state vector at time t″, L(t″+1) is the state at the next time t″+1, Q is the matrix of the linear relationship from the current state to the next state, W is the control matrix, and φ(t″) is the control input vector at time t″.

[0066] Further, in step S5, the method for performing intelligent analysis and optimization according to the changes of temperature data and humidity data during adjustment is:

[0067] The PID control algorithm is used to combine the proportional, integral and differential terms to adjust the working mode in real time. At the same time, the control strategy is optimized through adaptive adjustment and machine learning algorithms to continuously learn the fluctuation patterns of temperature and humidity data. In addition, intelligent decision-making is made through fuzzy control to handle the temperature and humidity adjustment requirements under uncertain and complex situations. The temperature and humidity adjustment process is coordinated through temperature and humidity coupling control. When the temperature and humidity are close to the user's preset target temperature and humidity, low power adjustment of non-critical equipment is selected. The expression formula of fuzzy control and intelligent decision-making is: where γ N (∈N) is the fuzzy membership function of temperature error, γ M (∈M) is the fuzzy membership function of humidity error;

[0068] In this embodiment, the control strategy is optimized through adaptive adjustment and machine learning algorithm, and the changing rules of temperature and humidity data are continuously learned, thereby improving the overall efficiency. At the same time, fuzzy control and intelligent decision-making methods can handle the temperature and humidity adjustment needs under uncertain and complex situations, especially when approaching the target temperature and humidity, low power adjustment of non-critical equipment is selected to achieve energy saving and improve system stability, which is conducive to improving the adaptability, efficiency and reliability of the constant temperature and humidity system.

[0069] The above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit the same. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that the technical solutions described in the aforementioned embodiments may still be modified, or some of the technical features may be replaced by equivalents. Such modifications or replacements will not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A constant temperature and humidity chamber control method, characterized in that: The following steps are involved: S1. Design a constant temperature and humidity system based on the Peltier effect to control the mode conversion by changing the polarity of the current. The modes include cooling and heating. S2, collect temperature and humidity data inside the constant temperature and humidity chamber through sensors, and monitor the changes of temperature and humidity in cooling mode and heating mode in real time; S3. According to the changes in humidity data, the constant temperature and humidity system is controlled to perform corresponding dehumidification and humidification work; S4, adjusting the temperature inside the constant temperature and humidity chamber by controlling the direction of the current according to the preset temperature conditions of the constant temperature and humidity chamber; S5. Perform intelligent analysis and optimization based on changes in temperature and humidity data during adjustment.

2. A constant temperature and humidity chamber control method according to claim 1, characterized in that: In step S1, a constant temperature and humidity system is designed. Based on the Peltier effect, the mode conversion is controlled by changing the polarity of the current. The modes include cooling and heating. The method is as follows: The refrigeration compressor, evaporator and air heater in the traditional constant temperature and humidity products are replaced by semiconductor refrigerators, and the dehumidifier and water tank heater are replaced by water-cooled semiconductor refrigerators. Two conductors of different materials are connected to form a thermocouple. The Peltier effect relies on the fact that when the current passes through the two semiconductors of different materials, the cold end of the thermocouple absorbs heat and the hot end releases heat, thereby achieving temperature regulation. By reversing the direction of the current, the functions of the cold end and the hot end are interchanged, so that the two modes of cooling and heating can be achieved. The Peltier effect and temperature regulation formula are: Where Z represents the total thermal effect caused by the current and temperature difference, is the thermoelectric coefficient, β is the thermal conductivity, ΔT is the temperature difference between the two ends, I is the current intensity, and ΔT 2 is the square of the temperature difference, C VB is the DC voltage, X thermo is the thermal resistance of the semiconductor, It represents the amount of heat transferred per unit time.

3. A constant temperature and humidity chamber control method according to claim 2, characterized in that: In step S2, the temperature data and humidity data inside the constant temperature and humidity chamber are collected by sensors, and the method for real-time monitoring of the changes in temperature and humidity in the cooling mode and the heating mode is as follows: Data is collected through sensors, including PT100 temperature sensor and DHT22 humidity sensor. The collected temperature data and humidity data are processed in real time by Arduino microcontroller. The temperature data and humidity data are calibrated and filtered. The temperature and humidity changes in the box are monitored according to the temperature data and humidity data. The target temperature is N target , the target humidity is M target , filtering processing formula: Where α is the time constant of the filter, s is the Laplace transform variable, and A(s) is the transfer function of the system.

4. A constant temperature and humidity chamber control method according to claim 3, characterized in that: In step S2, the temperature data and humidity data inside the constant temperature and humidity chamber are collected by sensors, and the method for real-time monitoring of the changes in temperature and humidity in the cooling mode and the heating mode is as follows: Determine whether to switch the working mode according to the changes in temperature and humidity. In cooling mode, the temperature gradually decreases and the humidity increases. In heating mode, the temperature increases and the humidity decreases. Real-time temperature and humidity data are transmitted through any communication protocol such as UART, I2C or SPI for real-time monitoring and adjustment. The judgment formula is: Where ΔN represents the current temperature N current With target temperature N target The difference between the two, ΔM represents the current humidity M current and target humidity M target The difference between N And ΔM>∈ M Switch working mode when N is the threshold of temperature deviation, ∈ M is the humidity deviation threshold.

5. A constant temperature and humidity chamber control method according to claim 4, characterized in that: In step S3, according to the change of humidity data, the method of controlling the constant temperature and humidity system to perform corresponding dehumidification and humidification is: The user sets the upper and lower humidity thresholds by himself. When the humidity is lower than 40%RH, the humidification operation is started, and when it exceeds 70%RH, the dehumidification operation is started. During the dehumidification process, the water-cooled semiconductor refrigerator uses the Peltier effect to reduce the cold end temperature to below the air dew point temperature, thereby achieving water vapor condensation. During humidification, the water in the humidification tank in the constant temperature and humidity chamber is heated by changing the DC voltage polarity of the water-cooled semiconductor refrigerator. After the water temperature rises, the water vapor evaporates to achieve the purpose of humidification. The humidity change formula is: in is the ratio of the temperature change rate to the humidity change rate, χ represents the linear influence of humidity change on temperature adjustment, δ represents the influence of temperature difference change on humidity adjustment, N dew Indicates the temperature at which water vapor in the air begins to condense. The humidity threshold control formula is: Among them, M current Represents the current humidity value, G′ means the dehumidification mode is activated, and G″ means the humidification mode is activated.

6. A constant temperature and humidity chamber control method according to claim 5, characterized in that: In step S3, according to the change of humidity data, the method of controlling the constant temperature and humidity system to perform corresponding dehumidification and humidification is: The dehumidification process and the humidification process are subject to real-time feedback from sensors, and the operation intensity is dynamically adjusted according to the actual humidity changes. At the same time, the humidification and dehumidification rates are adjusted, and temperature protection and humidity protection are implemented. The humidity data and operation logs are recorded, and the humidity control strategy is analyzed and optimized, and the formula is dynamically adjusted. in is the mass flow rate of moisture during the humidification process, is a function of the humidification process, ∈ M′ is the humidification efficiency, ΔN current is the current temperature difference, is the cooling power, is the mass flow rate of moisture during the dehumidification process, is a function of the dehumidification process, ∈ M″ is the dehumidification efficiency, ΔN current is the current temperature difference, is the heating power.

7. A constant temperature and humidity chamber control method according to claim 6, characterized in that: In step S4, according to the preset temperature condition of the constant temperature and humidity chamber, the method of adjusting the temperature inside the constant temperature and humidity chamber by controlling the direction of the current is: The temperature data collected from the constant temperature and humidity chamber in real time by the PT100 temperature sensor is compared with the target temperature preset by the user. By calculating the temperature difference, it is determined whether the current direction needs to be adjusted to perform any operation of heating or cooling. The PID control algorithm is used to smoothly adjust the temperature, and closed-loop control is performed by real-time monitoring of temperature data. When the temperature is higher than the target temperature preset by the user, the cooling mode is started; When the temperature is lower than the target temperature preset by the user, the current direction is adjusted in the reverse direction to start the heating mode. The expression of the PID control algorithm is: Where u(t′) is the control output, e(t′) is the error, K p is the proportional gain, K i is the integral gain, K d′ is the differential gain, is the integral of the error, is the derivative of the error.

8. A constant temperature and humidity chamber control method according to claim 7, characterized in that: In step S4, according to the preset temperature condition of the constant temperature and humidity chamber, the method of adjusting the temperature inside the constant temperature and humidity chamber by controlling the direction of the current is: Optimize response time and balance reaction strength by dynamically adjusting PID parameter model. If the temperature difference is less than the tolerance range of ±0.5℃, the temperature is considered stable. At the same time, over-temperature and low-temperature protection mechanisms are set, and PID parameters are optimized through adaptive algorithms. The control strategy is dynamically adjusted according to past temperature data, and the PID parameter model expression is dynamically adjusted: Where K p (t′) is a time-dependent function, is the reference value of the proportional gain, is the adjustment coefficient of proportional gain as the error changes, e(t′) is the current error, K i (t′) is the dynamically changing integral gain, is the reference value of the integral gain, is a coefficient controlling the effect of the error integral on the gain, represents the error integral from the start time to the current time t′, K d′ (t′) is the dynamically changing differential gain, is the reference value of the differential gain, is the differential gain adjustment coefficient, is the rate of change of error.

9. A constant temperature and humidity chamber control method according to claim 8, characterized in that: In step S5, the method for performing intelligent analysis and optimization according to the changes of temperature data and humidity data during adjustment is: By calculating the difference between the temperature data and humidity data and the target value, any one of the working modes of heating, cooling, humidification or dehumidification is intelligently selected. When the temperature data exceeds the user's preset target value, any one of the working modes of cooling or heating is selected to start according to the humidity data. At the same time, whether to start any one of the working modes of humidification or dehumidification is determined according to the error of the user's preset target value of the humidity data. When the temperature data and humidity data fluctuate at the same time, a balanced control strategy is adopted to achieve synchronous adjustment of the heating, cooling, humidification and dehumidification modes. The intelligent selection formula is: Where L(t″) is the state vector at time t″, L(t″+1) is the state at the next time t″+1, Q is the matrix of the linear relationship from the current state to the next state, W is the control matrix, and φ(t″) is the control input vector at time t″.

10. A constant temperature and humidity chamber control method according to claim 8, characterized in that: In step S5, the method for performing intelligent analysis and optimization according to the changes of temperature data and humidity data during adjustment is: The PID control algorithm is used to combine the proportional, integral and differential terms to adjust the working mode in real time. At the same time, the control strategy is optimized through adaptive adjustment and machine learning algorithms to continuously learn the fluctuation patterns of temperature and humidity data. In addition, intelligent decision-making is made through fuzzy control to handle the temperature and humidity adjustment requirements under uncertain and complex situations. The temperature and humidity adjustment process is coordinated through temperature and humidity coupling control. When the temperature and humidity are close to the user's preset target temperature and humidity, low power adjustment of non-critical equipment is selected. The expression formula of fuzzy control and intelligent decision-making is: where γ N (∈N) is the fuzzy membership function of temperature error, γ M (∈M) is the fuzzy membership function of humidity error.

Images