Automatic control method for freeze dryers based on alternating ice-melting capture and freeze dryer

Abstract

This invention relates to the field of freeze dryer control technology, specifically to an automatic control method for freeze dryers based on alternating trapping and melting, and a freeze dryer itself. The method analyzes the drying condition of the Freon liquid in the trap during the drying stage to determine the support strength of the Freon gas generated by the trap after the drying stage for the melting stage. Based on this support strength, it analyzes the pressure effect of the exothermic melting of the Freon gas in the trap coil on the coil pressure, determining the continued necessity of the trap in the melting stage. It analyzes the temperature change differences between traps at different locations, corrects the continued necessity, and obtains a final duration weight. Based on the final duration weight, it intelligently controls the duration of the freeze dryer's melting stage. This invention improves the freeze-drying efficiency of the freeze dryer by controlling the duration of a single trap in the melting stage.

Description

Technical Field

[0001] This invention relates to the field of freeze dryer control technology, specifically to an automatic control method for freeze dryers based on alternating ice-melting capture and a freeze dryer. Background Technology

[0002] Vacuum freeze-drying equipment, or freeze dryer for short, is a high-precision drying device that combines low-temperature freezing with vacuum dehydration. It utilizes the principle of sublimation to directly convert the moisture in the material from a solid state (ice) into a gaseous state (water vapor) and remove it, thereby preserving the material's biological activity, physical structure, and chemical composition.

[0003] Freeze dryers are mainly used in the pharmaceutical, food, biological product, and chemical industries. They are suitable for the dehydration and preservation of heat-sensitive substances, such as vaccines, enzymes, fruits, and vegetables. Traditional freeze dryers require shutdown during ice melting, resulting in significant drawbacks such as high energy consumption and low efficiency. Furthermore, the freeze dryer's compressor repeatedly absorbs and compresses the refrigerant from different collectors, achieving internal refrigerant circulation. Here, the refrigerant is Freon gas. However, the Freon gas received by the compressor at the receiving end may contain a small amount of liquid Freon due to incomplete vaporization of liquid Freon. This can cause liquid slugging in the compressor, potentially damaging it and reducing the freeze-drying efficiency of the object. Summary of the Invention

[0004] To address the technical problem of low freeze-drying efficiency in traditional freeze dryers, the present invention aims to provide an automatic control method for freeze dryers based on alternating ice-melting capture, as well as a freeze dryer itself. The specific technical solution adopted is as follows:

[0005] In a first aspect, embodiments of the present invention provide an automatic control method for a freeze dryer based on alternating ice-melting capture and a freeze dryer, the method comprising:

[0006] The operating data of the trap during the drying and melting stages were obtained separately;

[0007] Based on the operating data, the drying status of the Freon liquid in the drying stage of the trap was analyzed, and the support of the Freon gas generated by the trap after the drying stage for the ice melting stage was determined.

[0008] Based on the aforementioned support level, the impact of the exothermic melting of Freon gas in the collector coil on the pressure inside the coil is analyzed to determine the continued necessity of the collector during the melting stage.

[0009] The temperature variation differences between collectors at different locations are analyzed, and the necessity of continuous operation is corrected to obtain the final duration weight. Based on the final duration weight, the duration of the ice melting phase of the collector is intelligently controlled.

[0010] Furthermore, based on operational data, the analysis of the drying status of the Freon liquid during the drying stage of the trap, and the determination of the support strength of the Freon gas generated by the trap after the drying stage for the de-icing stage, include:

[0011] The amount of Freon gas generated by the collector during the drying stage is determined based on the duration of the drying stage and the flow rate of the Freon gas.

[0012] The drying stage is divided into ice layer stacking stages; the heat loss probability of each ice layer stacking stage is determined based on the temperature change of Freon gas and the ice layer thickness change in each ice layer stacking stage.

[0013] By combining the temperature equilibrium characteristics of the Freon gas generated by the collector during the drying stage, the duration of the drying stage, the Freon gas content, and the probability of heat loss, the support of the Freon gas generated by the collector after the drying stage for the ice melting stage can be determined.

[0014] Furthermore, dividing the drying stage into ice layer stacking stages includes: obtaining the ice layer boundary time of the trap during the drying stage, and dividing the drying stage into ice layer stacking stages based on the ice layer boundary time.

[0015] Further, determining the amount of Freon gas generated by the collector during the drying stage based on the duration of the drying stage and the flow rate of the Freon gas includes:

[0016] The average flow rate of Freon gas during the drying stage of the trap is obtained as the average flow rate; the product of the average flow rate and the duration of the corresponding drying stage of the trap is calculated as the Freon gas content generated by the trap during the drying stage.

[0017] Furthermore, determining the heat loss probability for each ice layer stacking stage based on the temperature change of the Freon gas and the ice layer thickness change during each ice layer stacking stage includes:

[0018] Obtain the thickness change corresponding to the initial moment of the ice layer during the ice layer stacking stage;

[0019] Obtain the temperature change of Freon gas at the start of the ice layer stacking stage;

[0020] The probability of heat loss for each ice layer stacking stage is determined based on the thickness change, the temperature change, and the duration of the ice layer stacking stage; wherein the temperature change is positively correlated with the probability of heat loss; and the thickness change and the duration of the ice layer stacking stage are both negatively correlated with the probability of heat loss.

[0021] Furthermore, the method for obtaining the support strength of the Freon gas generated by the collector after the drying stage for the ice-melting stage includes:

[0022] The sum of the heat loss probabilities of the trap during the ice layer stacking stage is calculated as the total heat loss probability;

[0023] Calculate the average temperature of the Freon gas produced by the trap during the drying stage;

[0024] Based on the Freon gas content, average temperature, duration of the drying stage, and total probability of heat loss, the support strength of the Freon gas generated by the collector after the drying stage for the ice-melting stage is determined. Among them, the Freon gas content and average temperature are positively correlated with the support strength, while the duration of the drying stage and the total probability of heat loss are negatively correlated with the support strength.

[0025] Furthermore, based on the aforementioned support strength, the analysis of the impact of the exothermic melting of Freon gas in the collector coil on the pressure within the coil, and the determination of the continued necessity of the collector during the melting stage, includes:

[0026] Based on the aforementioned support level, the ice-melting efficiency of the trap during the ice-melting stage is determined.

[0027] By combining the temperature data of Freon gas after the de-icing stage, the pressure deviation of the air pressure when compressed to liquid, and the de-icing efficiency of the collector during the de-icing stage, the degree of interference experienced by the collector during the de-icing stage can be determined; among them, the pressure deviation and the de-icing efficiency are both positively correlated with the degree of interference.

[0028] Analyze the temperature drop and pressure changes of the trap during the ice melting stage to determine the temperature-pressure change relationship coefficient corresponding to the trap;

[0029] The continued necessity of the trap during the ice-melting stage is determined by combining the degree of interference and the temperature-pressure change relationship coefficient; wherein, the degree of interference is negatively correlated with the continued necessity, and the temperature-pressure change relationship coefficient is positively correlated with the continued necessity.

[0030] Furthermore, determining the ice-melting efficiency of the trap during the ice-melting stage based on the support strength includes:

[0031] The ice-melting efficiency is determined by combining the level of support and the duration of the ice-melting phase; the duration of the ice-melting phase is negatively correlated with the ice-melting efficiency, while the level of support is positively correlated with the ice-melting efficiency.

[0032] Furthermore, the analysis of temperature variation differences between traps at different locations, and the correction of the continuous necessity to obtain the final duration weight, includes:

[0033] Calculate the temperature difference between the traps at different locations;

[0034] The continuous necessity is weighted by the normalized value of the temperature difference to obtain the continuous adjustment value;

[0035] The normalized value of the sum of the continuous adjustment value and the continuous necessity value is used as the final duration weight.

[0036] Secondly, a freeze dryer based on alternating ice-melting capture is provided, the freeze dryer comprising the following modules:

[0037] The data acquisition module is used to acquire the operating data of the trap during the drying and melting stages, respectively.

[0038] The drying stage analysis module is used to analyze the drying status of the Freon liquid in the collector during the drying stage based on the operating data, and to determine the support of the Freon gas generated by the collector after the drying stage for the ice melting stage.

[0039] The de-icing stage analysis module is used to analyze the impact of the exothermic de-icing of Freon gas in the trap coil on the pressure inside the coil based on the support strength, and to determine the continued necessity of the trap in the de-icing stage.

[0040] The intelligent control module is used to analyze the temperature change differences between collectors at different locations, correct the necessity of continuous operation, and obtain the final duration weight; based on the final duration weight, the duration of the ice melting stage of the collector is intelligently controlled.

[0041] Thirdly, embodiments of the present invention provide an electronic device, including a memory and a processor, wherein the memory stores executable code, and when the processor executes the executable code, it implements the various possible implementations of the first aspect.

[0042] Fourthly, embodiments of the present invention provide a computer program product comprising: computer program code, which, when executed on a computer, causes the computer to perform the method described in the first aspect or any possible implementation thereof.

[0043] Fifthly, embodiments of the present invention provide a computer-readable storage medium having a computer program stored thereon, which, when executed in a computer, causes the computer to perform the various possible implementations of the first aspect.

[0044] The embodiments of the present invention have at least the following beneficial effects:

[0045] This invention analyzes the potential damage to the compressor caused by a single trap during the drying and melting stages of a freeze dryer by considering the temperature and pressure changes of the refrigerant / gas flowing through the coil. It also calculates the final duration weight by incorporating temperature errors generated by alternating operation of different traps. By adjusting the duration of a single trap during the melting stage, the negative pressure steam generated by the steam heater is appropriately extended to assist evaporation within the trap coil, reducing the likelihood of liquid residue in each trap coil and decreasing the probability of liquid slugging in the compressor, thus reducing the probability of compressor knocking and improving the freeze-drying efficiency of the freeze dryer. Attached Figure Description

[0046] To more clearly illustrate the technical solutions and advantages in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0047] Figure 1 This is a flowchart of an automatic control method for a freeze dryer based on alternating ice-melting capture, provided in an embodiment of the present invention.

[0048] Figure 2 A flowchart illustrating a method for obtaining the support strength of Freon gas generated by the collector after the drying stage for the de-icing stage, according to an embodiment of the present invention.

[0049] Figure 3 This is a schematic diagram of a freeze dryer based on alternating ice-catching and melting, provided as an embodiment of the present invention. Detailed Implementation

[0050] To further illustrate the technical means and effects of the present invention in achieving the intended purpose, the following detailed description, in conjunction with the accompanying drawings and preferred embodiments, details the specific implementation, structure, features, and effects of an automatic control method for a freeze dryer based on alternating ice-catching and melting processes proposed in this invention.

[0051] In the following description, different "one embodiment" or "another embodiment" do not necessarily refer to the same embodiment. Furthermore, specific features, structures, or characteristics in one or more embodiments may be combined in any suitable form.

[0052] In the description of the embodiments of the present invention, unless otherwise stated, " / " means "or". For example, A / B can mean A or B. The "and / or" in the text is merely a description of the relationship between related objects, indicating that there can be three relationships. For example, A and / or B can mean: A exists alone, A and B exist simultaneously, and B exists alone. In addition, in the description of the embodiments of the present invention, "multiple" means two or more.

[0053] Hereinafter, the terms "first" and "second" are used for descriptive purposes only and should not be construed as implying or suggesting relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature.

[0054] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains.

[0055] The embodiments of the present invention will now be described with reference to the accompanying drawings. Those skilled in the art will recognize that, with technological advancements and the emergence of new scenarios, the technical solutions provided by the embodiments of the present invention are also applicable to similar technical problems.

[0056] The following description, in conjunction with the accompanying drawings, details an automatic control method for a freeze dryer based on alternating ice-melting capture, as well as a specific solution for the freeze dryer provided by this invention.

[0057] Please see Figure 1 The diagram illustrates a flowchart of an automatic control method for a freeze dryer based on alternating ice-melting capture, according to an embodiment of the present invention. The method includes the following steps:

[0058] Step S100: Obtain the operating data of the trap during the drying stage and the ice melting stage, respectively.

[0059] The automatic control system involved in this invention has two built-in traps. The drying and melting stages are switched via valves to ensure continuous production of freeze-dried products. The principle is as follows: Freon gas condenses and releases heat within the trap coils; this heat is conducted through the metal tube walls to the ice layer, raising the ice temperature above 0°C and causing it to melt.

[0060] It mainly includes the following four technical features:

[0061] 1. Hot Freon Ice Melting Technology: This technology uses Freon gas (at 70-120℃) discharged from the compressor of the refrigeration system as a heat source. The gas is introduced in reverse into the collector coil of the ice to be melted, and the ice layer is directly melted through heat exchange, replacing the traditional hot water or electric heating ice melting method.

[0062] 2. Vacuum compatibility: The ice melting process is carried out under negative pressure. The negative pressure steam generated by the steam heater assists in the ice melting, reduces vacuum loss, and avoids frequent vacuum breaks in the system.

[0063] 3. Energy recycling: The low-temperature Freon gas after ice melting is recovered into the refrigeration system, compressed and converted back into high-temperature gas, realizing thermal energy recycling and reducing energy consumption.

[0064] 4. Negative pressure enhances efficiency: The vacuum environment lowers the boiling point of water, and the melted ice water evaporates rapidly under low pressure and is discharged by the system vacuum pump, accelerating the shedding of the ice layer.

[0065] The main workflow of a freeze dryer includes a drying stage and an ice-melting stage:

[0066] Drying stage: Open the refrigerant inlet valve of trap A, and use the low-temperature Freon liquid transmitted by the refrigeration system to deliver it to the refrigerant inlet valve of trap A, so that the low-temperature Freon liquid evaporates and absorbs heat in the coil of trap A. Trapper A captures the water vapor sublimated by the refrigerant and freezes it; at this time, trap B is in the standby state after the ice melts, and its refrigerant inlet valve is closed.

[0067] De-icing stage: Once the ice layer thickness of collector A reaches the preset thickness threshold, close the refrigerant inlet valve of collector A to stop refrigeration. Open the hot refrigerant valve of collector A to introduce the Freon gas discharged during the drying stage into the coil of collector A; Hot refrigerant de-icing: The high-temperature gas condenses and releases heat in the coil, and the ice layer absorbs the heat and melts, taking approximately 5-15 minutes. The de-icing water is discharged through a drain pump, while a built-in steam heater generates negative pressure steam to prevent vacuum fluctuations. In this embodiment of the invention, the preset thickness threshold is 10 mm; in other embodiments, this value can be adjusted by the implementer according to actual conditions. It should be noted that the temperature of the Freon gas is 80°C.

[0068] Alternating Capture: After the ice melt is complete, close the hot refrigerant valve of trap A, restart the refrigeration valve, and put trap A into standby mode. Open the refrigeration valve of trap B to take over the water vapor capture task. The low-temperature Freon gas after ice melt in trap A returns to the compressor through the return gas pipeline, and is repressurized to start the cycle of trap B. The above process realizes the alternating cycle of trap A and trap B.

[0069] In addition, in the automatic control system, during the drying and de-icing stages of each trap, the flow rate v, temperature c, and ice thickness d of the Freon gas in the pipeline can be directly recorded and detected by the data monitoring platform of the automatic control system. These data are used as the operating data of each trap in its respective stage; that is, the operating data of the trap includes: the flow rate, temperature, and ice thickness of the Freon gas.

[0070] It should be noted that the recording frequency of the running data can be set manually. In this embodiment of the invention, the default frequency for monitoring and recording is 1 time / second. This invention takes the process of alternating between trap A and trap B as an example for analysis. The subsequent process of alternating between trap B and trap A can be analyzed and processed in the same way, and will not be described again.

[0071] Step S200: Analyze the drying status of the Freon liquid in the collector during the drying stage, and determine the support strength of the Freon gas generated by the collector after the drying stage for the ice melting stage.

[0072] For example, for Freon trap A, the potential danger of the compressor recovering Freon gas containing liquid Freon begins as early as the drying stage. During the drying stage, Freon trap A produces low-temperature liquid Freon from the refrigeration system. This liquid evaporates and absorbs heat within the coils of trap A. Even after the drying stage ends, although a large amount of Freon gas is produced in the coils, a small amount of liquid Freon, usually small water droplets, may still adhere to the inner wall of the coils. If trap A subsequently uses Freon gas for the de-icing stage, this Freon gas will re-enter the coils. Airflow may carry the liquid Freon adhering to the inner wall of the coils out of the coils and into the compressor's receiving port, potentially damaging the compressor. Therefore, based on operating data, the drying status of the liquid Freon in trap A during the drying stage can be analyzed to calculate the support provided by the Freon gas produced by trap A after the drying stage for the de-icing stage.

[0073] Please see Figure 2 , Figure 2 A flowchart illustrating the method for obtaining the support strength of the Freon gas generated by the collector after the drying stage for the de-icing stage; that is, in some possible implementations, the above step S200 can be achieved through the following process:

[0074] Step S210: Determine the amount of Freon gas generated by the collector during the drying stage based on the duration of the drying stage and the flow rate of the Freon gas.

[0075] The duration of the statistical trap A throughout the entire drying stage. This refers to the time it takes for the ice thickness data inside trap A to rise from 0 to a preset thickness threshold; and the calculation of the Freon gas flow rate data during the entire drying phase of trap A. average flow velocity Based on the duration and average flow rate of the drying stage, calculate the amount of Freon gas generated by collector A during its drying stage. .

[0076] Step S220: Divide the drying stage into ice layer stacking stages; determine the heat loss probability of each ice layer stacking stage based on the temperature change of Freon gas and the ice layer thickness change in each ice layer stacking stage.

[0077] During the drying stage of collector A, under normal circumstances, the thickness of the ice layer on the surface of collector A does not increase uniformly, but rather undergoes a rapid and fluctuating process: At the beginning of the drying stage, the temperature difference between the surface of collector A and the refrigerant is large, and the refrigerant's heat absorption efficiency is high, resulting in rapid Freon gas production. The refrigerant is a low-temperature liquid Freon. Then, as ice continues to form on the surface of collector A, it indicates that the temperature difference between the surface of collector A and the refrigerant begins to decrease significantly. At this point, the refrigerant's heat absorption efficiency is slow, and the Freon gas production efficiency is slow, and this process accounts for the majority of Freon gas production. Therefore, based on the Freon gas production status of collector A during its drying stage, the heat contained in the Freon gas during this stage can be analyzed. Combined with the Freon gas content, the support of the Freon gas produced by collector A after the drying stage for the ice-melting stage can be calculated.

[0078] First, the drying stage is divided into two ice layer stacking stages. Specifically, the ice layer boundary time of the trap in the drying stage is obtained, and the drying stage is divided into ice layer stacking stages based on the ice layer boundary time.

[0079] Specifically: throughout the entire drying phase of trap A, the ice layer thickness is... The moment corresponding to the maximum slope is designated as the ice layer boundary moment. The time periods on either side of the ice layer boundary moment within the drying stage are respectively designated as the rapid ice layer stacking stage and the slow ice layer stacking stage. These two stages are collectively referred to as the ice layer stacking stage of trap A during its drying process. Each ice layer thickness corresponds to a slope, and the slope of the ice layer thickness at different times represents the change in ice layer thickness at different times. In this invention, the slope of the first ice layer thickness data is assumed to be 1. The change in ice layer thickness at other times is calculated by using the ice layer thickness at the previous sampling time c, the ice layer thickness at the next sampling time c+1, and the time interval between adjacent sampling times to determine the change in ice layer thickness at sampling time c+1.

[0080] Within any given ice layer stacking stage, obtain the duration of that stage. ; Obtain the thickness change of the ice layer at the initial moment during the ice layer stacking stage. ; Obtain the temperature change corresponding to the initial moment of the ice layer stacking stage using Freon gas. ;

[0081] The probability of heat loss for each ice layer stacking stage is determined based on the thickness change, the temperature change, and the duration of the ice layer stacking stage; wherein the temperature change is positively correlated with the probability of heat loss; and the thickness change and the duration of the ice layer stacking stage are both negatively correlated with the probability of heat loss.

[0082] In some embodiments, the probability of heat loss during the current ice layer stacking phase The calculation formula is: The higher the probability of heat loss, the faster the refrigerant absorbs heat and converts into gaseous state per unit time during the current ice layer stacking stage. The more sensitive the external environment is to the refrigerant vaporization process, the more likely it is to generate a certain amount of heat loss. This is because in actual scenarios, a certain amount of heat will inevitably be wasted, and it is impossible to completely eliminate waste. In addition, the external environment itself has a significant impact on the refrigerant.

[0083] Step S230: Combining the temperature equilibrium characteristics of the Freon gas generated by the collector during the drying stage, the duration of the drying stage, the Freon gas content, and the probability of heat loss, determine the support of the Freon gas generated by the collector after the drying stage for the ice melting stage.

[0084] The sum of the heat loss probabilities of the trap during the ice layer stacking stage is calculated as the total heat loss probability;

[0085] Calculate the average temperature of the Freon gas produced by the trap during the drying stage;

[0086] Based on the Freon gas content, average temperature, duration of the drying stage, and total probability of heat loss, it was determined that the Freon gas generated by the collector after the drying stage is positively correlated with the support strength during the ice melting stage; the duration of the drying stage and the total probability of heat loss are negatively correlated with the support strength.

[0087] In some embodiments, the Freon gas generated by the trap A after the drying stage provides support for the de-icing stage. : ;in, This represents the average temperature of the Freon gas produced by collector A during its drying phase. This indicates the number of ice layer stacking stages contained in trap A during its drying stage; This indicates that the trap A is in its drying stage. The probability of heat loss during each ice layer stacking stage; This represents the total probability of heat loss.

[0088] The greater the support, the more supportive the environment is for the Freon gas produced by the trap A, and the smaller the resistance. The better the vaporization effect of the Freon liquid, the more liquid is converted into gas. It also reflects that the Freon gas produced by the trap A provides more stable and continuous heat to the subsequent ice-melting process. In addition, it also indicates that there is less likely to be obvious refrigerant liquid residue on the inner wall of the trap A coil.

[0089] Step S300: Based on the support strength, analyze the impact of the exothermic melting of Freon gas in the collector coil on the pressure inside the coil, and determine the continued necessity of the collector during the melting stage.

[0090] Besides the drying stage, during the de-icing stage, there is also a potential risk of liquid Freon in the Freon gas recovered by the compressor: the Freon gas generated in the drying stage acts as a heat source and is reintroduced into the coils of collector A, directly melting the ice layer through heat exchange; simultaneously, a steam heater generates negative pressure steam to assist in the de-icing process. However, during this de-icing stage, the Freon gas continuously releases heat to form low-temperature Freon gas, which to some extent changes the pressure in the coils of collector A, thereby altering the liquefaction temperature of the low-temperature Freon gas within the coils. If the low-temperature Freon gas is in an intermediate state between liquefaction and solidification at this time, a certain amount of liquid Freon may form in the corresponding coil, and then, along with the overall flow of low-temperature Freon gas, be carried into the receiving port of the compressor, potentially damaging the compressor. Therefore, the support provided by the Freon gas generated after the drying stage in collector A for the de-icing stage needs to be considered. Based on this, the influence of the exothermic melting of Freon gas in the coil of trap A on the pressure inside the coil is analyzed, and the continued necessity of trap A during the melting stage is calculated.

[0091] During the de-icing process of collector A, the melting phenomenon of the ice layer on its surface directly reflects the de-icing effect of the Freon gas generated during the drying stage on the ice layer adhering to the surface of collector A. Ideally, if there is no energy loss, the Freon gas should be converted into a liquid low-temperature Freon after the exothermic de-icing, rather than the low-temperature Freon gas in the actual scenario. This indicates that the exothermic de-icing of Freon gas is inevitably affected by energy loss, and this lost energy needs to be recompressed by the compressor to convert the gaseous Freon gas into a liquid state. Therefore, based on the support of the Freon gas generated by collector A after the drying stage for the de-icing stage, the degree of heat loss of collector A during the de-icing stage can be analyzed, and the degree of interference to the de-icing process of collector A during the de-icing stage can be calculated. .

[0092] First, based on the aforementioned support strength, the de-icing efficiency of the trap during the de-icing stage is determined. Then, combining the pressure deviation of the Freon gas temperature data compressed to the air pressure of the liquid after the de-icing stage, and the de-icing efficiency of the trap during the de-icing stage, the degree of interference experienced by the trap during the de-icing stage is determined. Specifically, both the pressure deviation and the de-icing efficiency are positively correlated with the degree of interference.

[0093] Obtain the duration of trap A throughout its entire melting phase. That is, the thickness of the ice layer inside trap A. The time it takes for the thickness to drop from a preset threshold of 10mm to 0.

[0094] The ice-melting efficiency is determined by combining the level of support and the duration of the ice-melting phase; the duration of the ice-melting phase is negatively correlated with the ice-melting efficiency, while the level of support is positively correlated with the ice-melting efficiency.

[0095] In some embodiments, the ice-melting efficiency of trap A during its ice-melting phase... The calculation formula is: The higher the ice-melting efficiency value, the better the Freon gas produced by the collector A during the drying stage is at melting the ice layer.

[0096] Acquire the temperature data of the Freon gas after the de-icing stage in collector A; the air pressure required to compress it into the liquid. Record the initial preset compression pressure value of the compressor. Determining the air pressure to be compressed into the liquid based on gas temperature is a well-known method that can be directly obtained using existing means, and the specific method varies depending on the actual scenario, so it will not be elaborated upon here. The initial preset compression pressure value of the compressor is directly set by the implementer.

[0097] Calculate air pressure Compared to the compressor's initial preset compression pressure value The difference is used as the pressure deviation between the temperature data of the Freon gas and the air pressure of the liquid after the de-icing stage in the trap.

[0098] In some embodiments, the degree of disturbance experienced by the trap during the ice-melting phase The calculation formula is: The greater the disturbance experienced by the trap during the ice-melting stage, the more energy the trap A actually loses during the ice-melting stage, reflecting that the Freon gas in the trap A coil is less close to the intermediate state of liquefaction.

[0099] The greater the disturbance experienced by the trap during the de-icing stage, the less the Freon gas in the trap A coil approaches a liquefied intermediate state. For the compressor receiving the low-temperature Freon gas generated during the de-icing stage, the less likely it is to collect liquid Freon at the compressor receiver. However, these characteristics alone are insufficient to indicate the necessity of extending the effect of trap A during the de-icing stage. This is because, during the de-icing stage, the Freon gas circulates in a closed loop within the coil, and its temperature dynamically changes. Since temperature directly affects molecular activity, it also affects pressure, causing the pressure within trap A's coil to dynamically change. Therefore, based on the degree of disturbance, it is necessary to further analyze the relationship between Freon gas temperature and pressure to calculate the continued necessity of trap A during the de-icing stage.

[0100] Furthermore, the temperature drop and pressure changes of the trap during the ice-melting stage were analyzed to determine the temperature-pressure change relationship coefficients corresponding to the trap:

[0101] Calculate the temperature drop change of the Freon gas at the beginning and end of the entire de-icing phase in trap A. , This refers to the absolute value of the temperature difference between the start and end of the ice-melting stage, and the corresponding pressure change required for liquefaction. , This is the absolute value of the difference between the temperature at the start of the melting stage and the pressure required for liquefaction at the end; it also includes the overall temperature drop change. Pressure change Determine the temperature and pressure variation coefficients of trap A. : The larger the value of the temperature-pressure change relationship coefficient, the less linear the temperature and pressure changes of the Freon gas in the coil during the entire de-icing stage of the trap A. This indicates that the temperature and pressure of the Freon gas in the coil fluctuate more violently and significantly after the de-icing stage. It also indicates that the temperature and pressure of the Freon gas in the coil are more affected by the combined interference of gas and liquid, reflecting that the Freon gas in the coil is more likely to contain liquid, forming an intermediate state of gas and liquid coexistence.

[0102] Finally, by combining the degree of interference and the temperature-pressure change relationship coefficient, the continued necessity of the trap during the ice-melting stage is determined; wherein, the degree of interference is negatively correlated with the continued necessity, and the temperature-pressure change relationship coefficient is positively correlated with the continued necessity.

[0103] In some embodiments, the continued necessity of the trap during the ice-melting phase The calculation formula is: ;norm is the normalization function, which can be the maximum or minimum value normalization function.

[0104] The higher the value of the continuous necessity, the more likely the Freon gas in the coil is to contain liquid after the de-icing stage, forming an intermediate state where gas and liquid coexist. This reflects that the Freon gas in the coil needs to continue the de-icing process to convert the liquid remaining in the coil into gas as much as possible.

[0105] Step S400: Analyze the temperature change differences between collectors at different locations, correct the necessity of continuous operation, and obtain the final duration weight; based on the final duration weight, intelligently regulate the duration of the ice melting stage of the collector.

[0106] Based on the necessity of continuity, the temperature change difference between trap A and trap B is further analyzed to correct the necessity of continuity, and the final duration weight of trap A during the ice melting stage is calculated.

[0107] After the de-icing stage of trap A, the compressor still serves as a transition point between trap A and trap B. Trapper A transfers the low-temperature Freon gas to the compressor, where it is repressurized and liquefied. The resulting liquid Freon is then transported to the coils of trap B for drying. Without external intervention, after traps A and B alternately operate multiple times, the actual temperature within each area will deviate significantly from the initial temperature. Continuing to operate according to the original predetermined procedure would further increase the probability of compressor damage. Therefore, based on the necessity of continued operation, the temperature difference between traps A and B can be further analyzed to adjust the necessity of continued operation, and the final duration weight of trap A during the de-icing stage can be calculated.

[0108] Calculate the temperature difference between the traps at different locations. Specifically, after the entire de-icing phase of trap A, calculate the temperature of the Freon gas inside the coil of trap A. Initial preset drying temperature in pipe B of the trap The difference between In this embodiment of the invention, the initial preset drying temperature inside the trap B pipe is... The value is -70℃.

[0109] The continuous necessity is weighted by the normalized value of the temperature difference to obtain the continuous adjustment value. Specifically, the normalized temperature difference value is recorded as the correction factor. The persistence necessity is weighted by the correction factor to obtain the persistence adjustment value. This persistence adjustment value is the product of the correction factor and the persistence necessity.

[0110] The normalized value of the sum of the continuous adjustment value and the continuous necessity value is used as the final duration weight.

[0111] In some embodiments, the final duration weight The calculation formula is: .

[0112] Finally, based on the final duration weight, the duration of the ice-melting phase of the trap is intelligently adjusted. Specifically: based on the final duration weight... Calculate the theoretical duration of trap A during the ice-melting phase. .

[0113] Please see Figure 3 , Figure 3 A schematic diagram of a freeze dryer based on alternating ice-melting capture is provided for embodiments of the present invention. The freeze dryer includes the following modules:

[0114] The data acquisition module is used to acquire the operating data of the trap during the drying and melting stages, respectively.

[0115] The drying stage analysis module is used to analyze the drying status of the Freon liquid in the collector during the drying stage based on the operating data, and to determine the support of the Freon gas generated by the collector after the drying stage for the ice melting stage.

[0116] The de-icing stage analysis module is used to analyze the impact of the exothermic de-icing of Freon gas in the trap coil on the pressure inside the coil based on the support strength, and to determine the continued necessity of the trap in the de-icing stage.

[0117] The intelligent control module is used to analyze the temperature change differences between collectors at different locations, correct the necessity of continuous operation, and obtain the final duration weight; based on the final duration weight, the duration of the ice melting stage of the collector is intelligently controlled.

[0118] Alternatively, the transmission medium may be a wired link, such as, but not limited to, coaxial cable, fiber optic cable and digital subscriber line, or a wireless link, such as, but not limited to, wireless Fidelity (WIFI), Bluetooth and mobile device networks.

[0119] It should be noted that the device provided in the above embodiments is only an example of the division of the above functional modules. In actual applications, the above functions can be assigned to different functional modules as needed, that is, the internal structure of the computer device can be divided into different functional modules to complete all or part of the functions described above.

[0120] This invention provides a computer device. Exemplarily, the computer device includes: a memory, a processor, and a computer program stored in the memory and running on the processor, wherein when the processor executes the computer program, the computer device can execute any of the aforementioned automatic control methods for freeze dryers based on alternating ice-catching and melting.

[0121] Furthermore, embodiments of the present invention also protect an apparatus that may include a memory and a processor, wherein the memory stores executable program code, and the processor is used to call and execute the executable program code to execute the automatic control method for freeze dryers based on alternating ice-melting provided in embodiments of the present invention.

[0122] In this embodiment of the invention, the device can be divided into functional modules according to the above method example. For example, each module can correspond to a separate function, or two or more functions can be integrated into one processing module. The integrated module can be implemented in hardware. It should be noted that the module division in this embodiment is illustrative and is only a logical functional division. In actual implementation, there may be other division methods.

[0123] When each module is divided according to its function, the device may also include a signal uploading module, a determination module, and an adjustment module. It should be noted that all relevant content of each step involved in the above method embodiments can be referenced from the functional descriptions of the corresponding functional modules, and will not be repeated here.

[0124] It should be understood that the apparatus provided in this embodiment of the invention is used to execute the above-described automatic control method for freeze dryers based on alternating ice capture and melting, and thus can achieve the same effect as the above-described implementation method.

[0125] When using integrated units, the device may include a processing module and a storage module. When applied to a device, the processing module can be used to control and manage the device's operations. The storage module can be used to support the device in executing program code, etc. The processing module may be a processor or a controller, which can implement or execute various exemplary logic blocks, modules, and circuits as described in this disclosure. The processor may also be a combination that implements computing functions, such as a combination of one or more microprocessors, a combination of Digital Signal Processing (DSP) and a microprocessor, etc., and the storage module may be a memory.

[0126] In addition, the device provided in the embodiments of the present invention may specifically be a chip, component or module. The chip may include a connected processor and a memory. The memory is used to store instructions. When the processor calls and executes the instructions, the chip can execute the automatic control method of freeze dryer based on alternating ice capture and melting provided in the above embodiments.

[0127] This invention also provides a computer-readable storage medium storing computer program code. When the computer program code is run on a computer, the computer executes the aforementioned method steps to implement the automatic control method for freeze dryers based on alternating ice-melting provided in the above embodiments.

[0128] This invention also provides a computer program product that, when run on a computer, causes the computer to perform the aforementioned steps to realize the automatic control method for freeze dryers based on alternating ice-melting provided in the above embodiments.

[0129] In this invention, the apparatus, computer-readable storage medium, computer program product, or chip provided in the embodiments are all used to execute the corresponding methods described above. Therefore, the beneficial effects they achieve can be referred to the beneficial effects in the corresponding methods described above, and will not be repeated here. Through the above description of the embodiments, those skilled in the art will understand that, for the sake of convenience and brevity, only the division of the above functional modules is used as an example. In practical applications, the above functions can be assigned to different functional modules as needed, that is, the internal structure of the device can be divided into different functional modules to complete all or part of the functions described above. In the embodiments provided by this invention, it should be understood that the disclosed apparatus and method can be implemented in other ways.

[0130] The device embodiments described above are merely illustrative. For example, the division of modules or units is only a logical functional division. In actual implementation, there may be other division methods. For example, multiple units or components may be combined or integrated into another device, or some features may be ignored or not executed. Furthermore, the coupling or direct coupling or communication connection shown or discussed may be through some interfaces; the indirect coupling or communication connection between devices or units may be electrical, mechanical, or other forms.

[0131] It should also be noted that, in this document, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or terminal device that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or terminal device. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or terminal device that includes said element.

[0132] It should be noted that the order of the above embodiments of the present invention is merely for descriptive purposes and does not represent the superiority or inferiority of the embodiments. The processes depicted in the accompanying drawings do not necessarily require a specific or sequential order to achieve the desired result. In some embodiments, multitasking and parallel processing are also possible or may be advantageous.

[0133] The various embodiments in this specification are described in a progressive manner. The same or similar parts between the various embodiments can be referred to each other. Each embodiment focuses on describing the differences from other embodiments.

[0134] The above content is only a specific embodiment of the present invention, but the protection scope of the present invention is not limited thereto. Any changes or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in the present invention should be included within the protection scope of the present invention.

Claims

1. An automatic control method for freeze-dryer based on alternate ice-melting trapping, characterized in that, The method comprises the following steps: Respectively acquire the operation data of the trap in the drying stage and the ice melting stage; According to the operation data, analyze the drying condition of the freon liquid in the drying stage of the trap, and determine the support degree of the freon gas generated after the drying stage of the trap on the ice melting stage; Based on the support degree, analyze the pressure influence of the freon gas after heat release and ice melting in the coil of the trap, and determine the necessity of the continuous operation of the trap in the ice melting stage; Analyze the temperature change difference between the traps at different positions, correct the necessity, and obtain the final continuous time weight; according to the final continuous time weight, intelligently control the continuous time of the trap in the ice melting stage; The support degree is obtained by: according to the time length of the trap in the drying stage and the flow rate of the freon gas, determining the freon gas content generated in the drying stage of the trap; the drying stage is divided into ice layer stacking stage; according to the temperature change of the freon gas and the thickness change of the ice layer in each ice layer stacking stage, the heat loss probability of each ice layer stacking stage is determined; combined with the temperature equalization characteristics of the freon gas generated in the drying stage of the trap, the time length of the drying stage, the freon gas content and the heat loss probability, the support degree of the freon gas generated after the drying stage of the trap on the ice melting stage is determined; The necessity of continuous operation is obtained by: based on the support degree, the ice melting efficiency of the trap in the ice melting stage is determined; combined with the pressure deviation of the temperature data compression of the freon gas after the ice melting stage to the liquid air pressure, the ice melting efficiency of the trap in the ice melting stage, the interference degree of the trap in the ice melting stage is determined; wherein, the pressure deviation and the ice melting efficiency are positively correlated with the interference degree; analyze the temperature drop of the trap in the ice melting stage and the pressure change, and determine the temperature pressure change relationship coefficient corresponding to the trap; combined with the interference degree and the temperature pressure change relationship coefficient, the necessity of continuous operation of the trap in the ice melting stage is determined; wherein, the interference degree is negatively correlated with the necessity of continuous operation, and the temperature pressure change relationship coefficient is positively correlated with the necessity of continuous operation.

2. The automatic control method of the freeze-dryer based on the alternate-trap ice-melting according to claim 1, characterized in that, The drying stage is divided into ice layer stacking stage, which comprises: acquiring the ice layer demarcation time of the trap in the drying stage, and dividing the drying stage into ice layer stacking stage based on the ice layer demarcation time.

3. The method of claim 1, wherein the method is characterized by, The freon gas content generated in the drying stage of the trap is determined by: acquiring the average value of the flow rate of the freon gas in the drying stage of the trap as the average flow rate, and calculating the product value of the average flow rate and the time length of the corresponding drying stage of the trap as the freon gas content generated in the drying stage of the trap. The heat loss probability of each ice layer stacking stage is determined by: acquiring the thickness change amount corresponding to the ice layer thickness at the starting time of the ice layer stacking stage; 4. The method of claim 1, wherein the method is an automatic control method of a freeze-drying machine based on the alternate-trap ice-melting, characterized in that, Acquire the temperature change amount corresponding to the freon gas at the starting time of the ice layer stacking stage; ​ ​ Determine the heat loss probability of each ice layer stacking stage according to the thickness variation, the temperature variation, and the length of the ice layer stacking stage; wherein the temperature variation is positively correlated with the heat loss probability; the thickness variation and the length of the ice layer stacking stage are negatively correlated with the heat loss probability.

5. The automatic control method for a freeze dryer based on alternating ice-melting capture according to claim 1, characterized in that, The method for obtaining the support strength of Freon gas generated by the trap after the drying stage on the ice melting stage comprises the following steps: Calculate the sum of the heat loss probabilities of the trap in the ice layer stacking stage as the total heat loss probability; Calculate the average temperature of the Freon gas generated by the trap in the drying stage as a whole; Determine the support strength of Freon gas generated by the trap after the drying stage on the ice melting stage according to the Freon gas content, the average temperature, the length of the drying stage, and the total heat loss probability; wherein the Freon gas content and the average temperature are positively correlated with the support strength; the length of the drying stage and the total heat loss probability are negatively correlated with the support strength.

6. The method of automatic control of an alternating-trap freeze-dryer based on ice-melting according to claim 1, wherein, Determine the ice melting efficiency of the trap in the ice melting stage based on the support strength, which comprises the following steps: Determine the ice melting efficiency in combination with the support strength and the length of the ice melting stage; wherein the length of the ice melting stage is negatively correlated with the ice melting efficiency, and the support strength is positively correlated with the ice melting efficiency.

7. The automatic control method for a freeze dryer based on alternating ice-melting capture according to claim 1, characterized in that, The method for correcting the necessity of continuous operation by analyzing the temperature variation difference between traps at different positions to obtain the final continuous length weight comprises the following steps: Calculate the temperature difference value between traps at different positions; Weight the necessity of continuous operation by the normalized value of the temperature difference value to obtain a continuous adjustment value; Take the normalized value of the sum of the continuous adjustment value and the necessity of continuous operation as the final continuous length weight.

8. A freeze dryer based on alternate trapping of ice melt, characterized in that, The freeze dryer is used to realize the automatic control method of the freeze dryer based on alternating ice melting according to any one of claims 1-7, and comprises the following modules: A data acquisition module is configured to acquire the operation data of the trap in the drying stage and the ice melting stage, respectively; A drying stage analysis module is configured to analyze the drying condition of the Freon liquid in the drying stage of the trap according to the operation data, and determine the support strength of the Freon gas generated by the trap after the drying stage on the ice melting stage; An ice melting stage analysis module is configured to analyze the influence of the Freon gas heat dissipation and ice melting in the trap on the pressure in the coil based on the support strength, and determine the necessity of continuous operation of the trap in the ice melting stage; An intelligent control module is configured to correct the necessity of continuous operation by analyzing the temperature variation difference between traps at different positions to obtain the final continuous length weight, and intelligently control the continuous length of the ice melting stage of the trap according to the final continuous length weight.

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