Intelligent fresh-keeping method and system, intelligent fresh-keeping refrigerator

Abstract

The application discloses an intelligent fresh-keeping method and system, an intelligent fresh-keeping refrigerator and a method for controlling the refrigerator. The method comprises the following steps: placing fruits to be preserved into an ice greenhouse of the refrigerator, setting a quality grade of the fruits to be preserved; when it is detected that the weight of the fruits to be preserved is greater than a set weight threshold, detecting the core temperature of the fruits to be preserved; if the core temperature of the fruits to be preserved is greater than a set ice temperature threshold, controlling the ice greenhouse to stepwise reduce the temperature, otherwise, controlling the ice greenhouse to maintain the ice temperature; when the ice greenhouse is controlled to stepwise reduce the temperature, setting a starting stepwise temperature and a stepwise maintenance time based on the weight, the core temperature and the quality grade of the fruits to be preserved; and when the ice greenhouse is controlled to maintain the ice temperature, controlling the compressor, the air door and the vacuum pump based on the core temperature of the fruits to be preserved.

Description

Technical Field

[0001] This invention belongs to the field of refrigerator preservation technology, and more specifically, relates to an intelligent preservation method and system, and an intelligent preservation refrigerator. Background Technology

[0002] Fruits undergo vigorous respiration and metabolism after harvest, making them prone to water loss, wilting, and spoilage. Ice-temperature preservation (typically -1°C to 0°C) is widely recognized as an effective technology for extending the shelf life of these fruits. However, many fruits suffer from ice damage (e.g., strawberries), and existing refrigerators face the following technical challenges in achieving an ice-temperature environment for these fruits: 1. Localized frostbite: The evaporator and air duct outlet temperature of the refrigerator's air-cooling system are much lower than the ice temperature setting (-1℃). The cold air blows directly onto the fruit to be preserved, or water vapor condenses and frosts on the surface of low-temperature components. The frost layer continues to absorb heat from the fruit to be preserved, resulting in localized excessively low temperatures, causing frostbite, water leakage, and deterioration in taste of the fruit.

[0003] 2. Uncontrolled humidity: Ice-temperature environments require high relative humidity (>90% for strawberries) to inhibit water loss from the fruit to be preserved. However, traditional air-cooled refrigerators force dehumidification during cooling, resulting in excessively low humidity. Simply adding a humidifier can easily cause frost to form on low-temperature components, creating a vicious cycle of "high humidity-frost-freezing damage".

[0004] 3. Temperature shock and condensation: When fruits to be preserved are placed directly from room temperature into the ice-temperature room, the sudden drop in temperature will cause condensation to form on the surface of the fruits, which will then breed mold and accelerate decay.

[0005] 4. Ignoring the initial quality differences of fruits awaiting preservation: Fruits at different stages of maturity (green, semi-ripe, fully ripe) show significant differences in their sensitivity to low temperatures and respiration rates. Unripe fruits require lower temperatures to inhibit respiration but have a higher frost damage threshold; fully ripe fruits respire vigorously and are extremely susceptible to frost damage. Existing refrigerators use uniform ice temperatures, leading to poor ripening of unripe fruits or frost damage to overripe fruits.

[0006] 5. Ignoring dynamic changes during storage: As the number of storage days increases, the physiological state of the fruit to be preserved (firmness, sugar content, water loss rate) changes continuously, and the optimal preservation parameters (ice temperature, humidity) should also be adjusted accordingly. Existing refrigerators use fixed parameters throughout the entire process, leading to accelerated quality deterioration in the later stages. Summary of the Invention

[0007] To address the shortcomings of existing technologies, this invention provides an intelligent preservation method and system, and an intelligent preservation refrigerator.

[0008] The present invention adopts the following technical solution.

[0009] A first aspect of the present invention provides an intelligent preservation method, comprising: Place the fruit to be preserved in the refrigerator's ice compartment and set the quality level of the fruit to be preserved. When the weight of the fruit to be preserved is detected to be greater than the set weight threshold, the core temperature of the fruit to be preserved is detected. If the core temperature of the fruit to be preserved is greater than the set ice temperature threshold, the ice compartment is controlled to cool down in stages; otherwise, the ice compartment is controlled to maintain the ice temperature. The controlled ice-cooling chamber is cooled in stages as follows: An initial stage temperature and a stage duration are set based on the weight, core temperature, and quality grade of the fruit to be preserved. The ice-cooling chamber is then cooled in stages based on the initial stage temperature and stage duration. After the stage cooling is completed, target ice-temperature ranges for different quality grades are set. It is then determined whether the core temperature of the fruit to be preserved is greater than the sum of the lower limit of the corresponding target ice-temperature range and the set first margin. If not, the ice-cooling chamber is maintained at the ice temperature. If so, the current ice-cooling chamber temperature is maintained until the set maximum extension time has elapsed, or until the core temperature of the fruit to be preserved is still greater than the sum of the lower limit of the corresponding target ice-temperature range and the set first margin. The method for controlling the ice temperature in the ice chamber is as follows: based on the current storage period of the fruit to be preserved, the target ice temperature range for different quality grades is adaptively adjusted. If the core temperature of the fruit to be preserved is greater than the upper limit of the corresponding adaptively adjusted target ice temperature range, the compressor, damper, and vacuum pump are turned on for cooling. If the core temperature of the fruit to be preserved is less than or equal to the lower limit of the corresponding adaptively adjusted target ice temperature range, it is determined whether the current relative humidity is greater than the set humidity threshold. If so, the vacuum pump is turned on for dehumidification; otherwise, the compressor, damper, and vacuum pump are all turned off.

[0010] Preferably, the setting of the initial step temperature and the step maintenance time based on the weight, core temperature, and quality grade of the fruit to be preserved specifically involves: If the core temperature of the fruit to be preserved is greater than the set maximum temperature threshold, the starting step temperature is the set first temperature; if the core temperature of the fruit to be preserved is greater than the set intermediate temperature threshold and less than or equal to the set maximum temperature threshold, the starting step temperature is the set second temperature; if the core temperature of the fruit to be preserved is greater than the set ice temperature threshold and less than or equal to the set intermediate temperature threshold, the starting step temperature is the set third temperature. The first temperature is greater than the second temperature, and the second temperature is greater than the third temperature; Different quality correction coefficients are set for different quality grades; the weight of the fruit to be preserved is divided by the set standard weight to obtain the normalized weight, the normalized weight is multiplied by the set unit correction time to obtain the weight correction time, the set basic step maintenance time is added to the weight correction time, and the sum is multiplied by the set quality correction coefficient to obtain the step maintenance time.

[0011] Preferably, the step-down cooling of the ice-cooling chamber based on the initial step temperature and the step duration specifically includes: The target temperature of the first stepped ice chamber is the initial stepped temperature. The target temperature decreases by a set unit temperature for each stepped temperature until the target temperature of the stepped temperature reaches the set minimum temperature. Each step uses a PI controller to control the compressor frequency and damper duty cycle of the ice chamber to stabilize the temperature of the ice chamber within the corresponding temperature range of the step. The upper limit of the corresponding temperature range of the step is the sum of the target temperature of the step and the set second margin, and the lower limit of the corresponding temperature range of the step is the difference between the target temperature of the step and the set second margin. Furthermore, at each step, after each set first cycle, the core temperature of the fruit to be preserved is detected. If the core temperature of the fruit to be preserved for a set number of consecutive first weeks is less than or equal to the difference between the target temperature of the step and the set third margin, or if the duration of the current step is greater than or equal to a set proportion of the step maintenance time and the core temperature of the fruit to be preserved is within the temperature range corresponding to the step, then the current step ends and the next step begins. Otherwise, the next step begins after the duration of the current step equals the step maintenance time, until all steps are completed; where the third margin is less than the second margin.

[0012] Preferably, maintaining the current ice-temperature chamber temperature until the set maximum extension time has elapsed, or until the core temperature of the fruit to be preserved is still greater than the sum of the lower limit of the corresponding target ice-temperature range and the set first margin, specifically means: Maintain the current temperature of the ice-cooling chamber, and check the core temperature of the fruit to be preserved every second set cycle. If the core temperature of the fruit to be preserved is less than or equal to the sum of the lower limit of the corresponding target ice temperature range and the set first margin, then control the ice-cooling chamber to maintain the ice temperature. If, after the set maximum extension time, the core temperature of the fruit to be preserved is still greater than the sum of the lower limit of the corresponding target ice temperature range and the set first margin, then check the current core temperature of the fruit to be preserved. If the core temperature of the fruit to be preserved is greater than the set ice temperature threshold, then control the ice-cooling chamber to cool down in stages again; otherwise, control the ice-cooling chamber to maintain the ice temperature.

[0013] Preferably, the adaptive correction of the target ice temperature range for different quality grades based on the current storage period of the fruit to be preserved specifically involves: Multiply the storage period of the fruit to be preserved by the set storage time correction factor. If the result of the multiplication is greater than the set maximum correction offset, then the storage period correction offset is equal to the set maximum correction offset; otherwise, the storage period correction offset is equal to the multiplication result. If the sum of the upper limit of the target ice temperature range for each quality level and the storage period correction offset is less than or equal to the freezing point temperature, then the upper limit of the target ice temperature range after adaptive correction for the corresponding quality level is equal to the sum of the upper limit of the target ice temperature range for the corresponding quality level and the storage period correction offset; otherwise, the upper limit of the target ice temperature range after adaptive correction for the corresponding quality level is equal to the freezing point temperature. If the sum of the lower limit of the target ice temperature range for each quality level and the storage period correction offset is less than or equal to the difference between the freezing point temperature and the fourth margin, then the lower limit of the target ice temperature range after adaptive correction for the corresponding quality level is equal to the sum of the lower limit of the target ice temperature range for the corresponding quality level and the storage period correction offset; otherwise, the lower limit of the target ice temperature range after adaptive correction for the corresponding quality level is equal to the difference between the freezing point temperature and the fourth margin.

[0014] Preferably, the storage period of the fruit to be preserved is as follows: When fruits to be preserved are placed in the ice-temperature room, the current storage period of the fruits to be preserved is 0. When the time of day reaches the set time, if the ice-temperature room is controlled to maintain the ice temperature, the storage period is increased by 1; otherwise, the current storage period is maintained. When the storage period exceeds the set first storage period threshold, an early warning is issued. When the storage period exceeds the set second storage period threshold, the control of the ice and cold chamber to maintain the ice temperature is forcibly terminated, and the temperature of the ice and cold chamber is maintained at the set refrigeration temperature, and an alarm is triggered.

[0015] Preferably, the step of activating the compressor, damper, and vacuum pump for cooling specifically involves: The compressor is turned on at a set frequency, and the damper opens and closes in a cyclical manner. Obtain the compressor power. If the compressor power is less than the set light load power threshold, the vacuum pump and damper will open and close synchronously. Otherwise, the vacuum pump will always be on during cooling. The opening and closing times of the damper in each cycle, as well as the power of the vacuum pump, are calculated based on the weight and storage period of the fruit to be preserved. Once the core temperature of the fruit to be preserved is less than or equal to the lower limit of the corresponding adaptively corrected target ice temperature range, the compressor, damper, and vacuum pump are turned off, and the process returns to the step of adaptively correcting the target ice temperature range for different quality grades based on the current storage period of the fruit to be preserved.

[0016] Preferably, the opening and closing durations of the damper in each cycle, as well as the power of the vacuum pump, are calculated based on the weight and storage period of the fruit to be preserved, specifically: Subtract the product of the set first storage period correction coefficient and the storage period from 1. If the result of the subtraction is greater than the set lower limit of the opening duration correction, then the opening duration correction coefficient is equal to the subtraction result; otherwise, the opening duration correction coefficient is equal to the set lower limit of the opening duration correction. Add the product of the set opening weight correction coefficient and the normalized weight to the set base opening duration, and multiply the sum by the opening duration correction coefficient to obtain the opening duration. The shutdown duration is obtained by subtracting the set shutdown weight correction factor and the normalized weight from the set base shutdown duration, and the shutdown duration is greater than or equal to 0. If the weight of the fruit to be preserved is less than the set first weight, the base power of the vacuum pump is the first power. If the weight of the fruit to be preserved is greater than or equal to the set first weight and less than the set second weight, the base power of the vacuum pump is the second power. If the weight of the fruit to be preserved is greater than or equal to the set second weight, the base power of the vacuum pump is the third power. The first power is less than the second power, and the second power is less than the third power. Subtract the product of the set second storage period correction coefficient and the storage period from 1. If the result of the subtraction is greater than the set lower limit of vacuum pump power correction, the vacuum pump power correction coefficient is equal to the result of the subtraction. Otherwise, the vacuum pump power correction coefficient is equal to the set lower limit of vacuum pump power correction. Multiply the base power of the vacuum pump by the vacuum pump power correction coefficient to obtain the power of the vacuum pump.

[0017] Preferably, the step of turning on the vacuum pump for dehumidification specifically involves: During dehumidification, the vacuum pump operates at its first power. After starting the set third cycle, the vacuum pump is turned off, and the process returns to the step of adaptively correcting the target ice temperature range for different quality grades based on the current storage period of the fruit to be preserved.

[0018] Preferably, the compressor, damper, and vacuum pump are all turned off, specifically: If the compressor, damper, and vacuum pump were previously on, and it is determined at the current moment that the compressor, damper, and vacuum pump are all off, then the compressor and damper will immediately close. If the weight of the fruit to be preserved is greater than or equal to the set second weight, then the vacuum pump will continue to operate for the set extended time before closing; otherwise, it will close immediately.

[0019] Preferably, when maintaining the ice temperature, if the opening of the ice chamber door is detected, all outputs of the compressor, damper and vacuum pump are stopped, and the weight of the fruit to be preserved is detected again after the ice chamber door is closed again.

[0020] A second aspect of the present invention provides an intelligent preservation system based on the method described in the first aspect of the present invention, comprising: a control status judgment module for the ice-temperature chamber, a module for controlling the stepped cooling of the ice-temperature chamber, and a module for controlling the ice-temperature chamber to maintain its temperature, specifically: Ice compartment temperature control status judgment module: After placing the fruit to be preserved into the ice compartment of the refrigerator and setting the quality grade of the fruit to be preserved, when it is detected that the weight of the fruit to be preserved is greater than the set weight threshold, the module detects the core temperature of the fruit to be preserved; if the core temperature of the fruit to be preserved is greater than the set ice temperature threshold, the module controls the ice compartment to cool down in stages; otherwise, the module controls the ice compartment to maintain the ice temperature. The ice-cooling chamber stepped cooling module is used to set the initial stepped temperature and the stepped maintenance time based on the weight, core temperature, and quality grade of the fruit to be preserved. Based on the initial stepped temperature and the stepped maintenance time, it controls the stepped cooling of the ice-cooling chamber. After the stepped cooling is completed, it sets the target ice temperature range for different quality grades and determines whether the core temperature of the fruit to be preserved is greater than the sum of the lower limit of the corresponding target ice temperature range and the set first margin. If not, it controls the ice-cooling chamber to maintain the ice temperature; if so, it maintains the current ice-cooling chamber temperature until the set maximum extension time has elapsed, or until the core temperature of the fruit to be preserved is still greater than the sum of the lower limit of the corresponding target ice temperature range and the set first margin. The ice temperature control module for maintaining the ice temperature in the ice-temperature chamber is used to adaptively adjust the target ice temperature range for different quality grades based on the current storage period of the fruit to be preserved. If the core temperature of the fruit to be preserved is greater than the upper limit of the corresponding adaptively adjusted target ice temperature range, the compressor, damper, and vacuum pump are turned on for cooling. If the core temperature of the fruit to be preserved is less than or equal to the lower limit of the corresponding adaptively adjusted target ice temperature range, it is determined whether the current relative humidity is greater than the set humidity threshold. If so, the vacuum pump is turned on for dehumidification; otherwise, the compressor, damper, and vacuum pump are all turned off.

[0021] A third aspect of the present invention provides an intelligent preservation refrigerator that integrates the intelligent preservation system described in the second aspect of the present invention.

[0022] The beneficial effects of this invention are compared with those of the prior art: 1. This invention dynamically determines whether to first cool in stages and then maintain the ice temperature or directly maintain the ice temperature based on the core temperature. This avoids excessive cooling that could cause chilling injury or excessive temperature difference that could cause condensation. Furthermore, it adjusts the initial stage temperature and the stage maintenance time based on the fruit weight, core temperature, and quality grade to ensure that fruits in different initial states quickly and safely reach the appropriate ice temperature. During the ice temperature maintenance stage, it adaptively adjusts the target ice temperature range in conjunction with the storage period and triggers refrigeration or dehumidification according to the core temperature and humidity conditions, thereby effectively extending the shelf life.

[0023] 2. This invention sets the initial step temperature according to the core temperature and adjusts the step maintenance time according to the weight and quality grade, so that the cooling start point and cooling rhythm are more in line with the actual thermal state and quality requirements of the fruit.

[0024] 3. This invention uses a step-by-step approach to gradually decrease the target temperature, and within each step, it uses both core temperature feedback and duration as dual conditions to control the switching of steps, which can prevent the cooling from being too fast or too slow, and improve the stability and efficiency of the cooling process.

[0025] 4. If the core temperature is still too high after the step cooling process, the present invention determines whether the step cooling process needs to be restarted to avoid affecting the preservation effect due to insufficient cooling in one step.

[0026] 5. This invention adaptively adjusts the upper and lower limits of the target ice temperature range according to the storage period, so that the ice temperature control is dynamically optimized as the fruit is stored for a period of time, preventing the quality from deteriorating later.

[0027] 6. This invention provides an early warning or forcibly exits ice-temperature control and switches to refrigeration when the storage period reaches a threshold, which can prevent fruits from spoiling due to prolonged storage and improve safety.

[0028] 7. During refrigeration, the present invention adjusts the coordinated action of the vacuum pump and damper according to the power status of the compressor, and calculates the cycle time and pump power through weight and storage period to balance refrigeration efficiency and power.

[0029] 8. During the refrigeration process, the present invention adjusts the opening and closing time of the damper and the power of the vacuum pump by adjusting the weight and storage period, so that the refrigeration capacity can be automatically adapted to the fruit loading and storage time.

[0030] 9. This invention operates at a fixed low power and stops after a set cycle during dehumidification, which can quickly reduce excessive humidity and avoid fruit dehydration caused by prolonged dehumidification.

[0031] 10. The present invention determines whether the vacuum pump should be delayed and shut off based on the weight of the fruit. When the fruit is heavy, the time is extended to suppress the rise in humidity.

[0032] 11. This invention prevents cold air loss or misoperation during door opening by performing door opening detection.

[0033] 12. This invention modularizes the intelligent preservation method, which facilitates the automated operation of the intelligent preservation method.

[0034] 13. This invention integrates an intelligent preservation system into a refrigerator, enabling the refrigerator to have adaptive ice temperature control capabilities, thereby improving the preservation effect of fruit storage and user convenience. Attached Figure Description

[0035] Figure 1 This is an overall flowchart of the intelligent preservation method of the present invention; Figure 2 Flowchart for stepped cooling; Figure 3 Flowchart for maintaining ice temperature; Figure 4A flowchart for dynamic adjustment and early warning of storage period; Figure 5 This is a schematic diagram of a refrigerator. Figure 6 This is a schematic diagram of an ice-temperature chamber.

[0036] 1 is the refrigerator compartment, 2 is the ice-temperature compartment, 3 is the freezer compartment; 4 is the ice-temperature drawer, 5 is the weight sensor, 6 is the vacuum pump, 7 is the temperature sensor, 8 is the humidity sensor, 9 is the infrared temperature sensor, and 10 is the heater. Detailed Implementation

[0037] To make the objectives, technical solutions, and advantages of this invention clearer, the technical solutions of this invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of this invention. The embodiments described in this application are merely some embodiments of this invention, and not all embodiments. Based on the spirit of this invention, all other embodiments obtained by those skilled in the art without creative effort are within the protection scope of this invention.

[0038] like Figure 1 As shown, Embodiment 1 of the present invention proposes an intelligent preservation method, comprising: S1. Place the fruit to be preserved in the freezer compartment of the refrigerator and set the quality level of the fruit to be preserved. It should be noted that the fruits to be preserved in this embodiment are those that are susceptible to chilling injury, such as strawberries; and only the same type of fruit is placed in each ice-cooled greenhouse at a time. The quality grade of the fruit to be preserved can be judged by the user through experience, input through the operation interface of the ice-temperature room, or by obtaining the quality parameters of the fruit to be preserved by integrating various sensors and detection devices in the ice-temperature room. In this embodiment, the fruit to be preserved is strawberry, and the quality parameters of the fruit to be preserved include the soluble solids content, hardness and color parameters of strawberry at room temperature. If the soluble solids content of the fruit to be preserved is less than or equal to the set first soluble solids content threshold (6.5% in this embodiment), and the hardness is greater than the set second hardness threshold (4.5N in this embodiment), and the color parameter is less than or equal to the set first color parameter threshold (20 in this embodiment), then the quality grade is considered to be... =1; If the soluble solids content of the fruit to be preserved is greater than the set second soluble solids content threshold (7.5% in this embodiment), or the hardness is less than or equal to the set first hardness threshold (3.5N in this embodiment), or the color parameter is greater than the set second color parameter threshold (25 in this embodiment), then the quality grade is considered to be... It is 3; In other cases, the quality grade is considered... It is 2; Quality grade The numbers 1, 2, and 3 represent strawberries that are green-ripe, semi-ripe, and fully ripe, respectively.

[0039] S2. When the weight of the fruit to be preserved is less than or equal to the set weight threshold, the refrigerator will display a message on the screen saying "Please place the fruit to be preserved" and return to S1; otherwise, proceed to S3. Specifically, the weight threshold set in this embodiment is 10g.

[0040] S3. When the weight of the fruit to be preserved is detected to be greater than the set weight threshold, the core temperature of the fruit to be preserved is detected by an infrared temperature sensor. If the core temperature of the fruit to be preserved is greater than the set ice temperature threshold, then enter S4 to control the ice chamber to cool down in stages; otherwise, enter S5 to control the ice chamber to maintain the ice temperature. Specifically, the ice temperature threshold set in this embodiment is 5°C.

[0041] S4, such as Figure 2 As shown, the step-down cooling of the ice-cooling chamber is controlled as follows: An initial step temperature and a step-down duration are set based on the weight, core temperature, and quality grade of the fruit to be preserved. The ice-cooling chamber is then controlled to cool step-down based on the initial step temperature and the step-down duration. After the step-down cooling is completed, target ice-temperature ranges for different quality grades are set. It is determined whether the core temperature of the fruit to be preserved is greater than the sum of the lower limit of the corresponding target ice-temperature range and the set first margin. If not, the ice-cooling chamber is controlled to maintain the ice temperature; if so, the current ice-cooling chamber temperature is maintained until the set maximum extension time has elapsed, or until the core temperature of the fruit to be preserved is still greater than the sum of the lower limit of the corresponding target ice-temperature range and the set first margin. S5, such as Figure 3 As shown, the ice temperature in the ice-cooling chamber is maintained by: adaptively adjusting the target ice temperature range for different quality grades based on the current storage period of the fruit to be preserved; if the core temperature of the fruit to be preserved is greater than the upper limit of the corresponding adaptively adjusted target ice temperature range, the compressor, damper, and vacuum pump are turned on for cooling; if the core temperature of the fruit to be preserved is less than or equal to the lower limit of the corresponding adaptively adjusted target ice temperature range, it is determined whether the current relative humidity is greater than the set humidity threshold. If so, the vacuum pump is turned on for dehumidification; otherwise, the compressor, damper, and vacuum pump are all turned off. Specifically, the relative humidity is the relative humidity of the ice-cooled greenhouse, and the humidity threshold set in this embodiment is 93%.

[0042] It should be noted that this embodiment, by dynamically determining whether to first cool in stages and then maintain the ice temperature or directly maintain the ice temperature based on the core temperature, can avoid excessive cooling leading to chilling injury or excessive temperature difference leading to condensation. Furthermore, by adjusting the initial stage temperature and the stage maintenance time based on the fruit weight, core temperature, and quality grade, it ensures that fruits in different initial states can quickly and safely reach the appropriate ice temperature. During the ice temperature maintenance stage, the target ice temperature range is adaptively adjusted in conjunction with the storage period, and refrigeration or dehumidification is triggered according to the core temperature and humidity conditions, thereby effectively extending the shelf life.

[0043] In this preferred embodiment, the setting of the initial step temperature and the step maintenance time based on the weight, core temperature, and quality grade of the fruit to be preserved specifically involves: If the core temperature of the fruit to be preserved is greater than the set maximum temperature threshold, the starting step temperature is the set first temperature; if the core temperature of the fruit to be preserved is greater than the set intermediate temperature threshold and less than or equal to the set maximum temperature threshold, the starting step temperature is the set second temperature; if the core temperature of the fruit to be preserved is greater than the set ice temperature threshold and less than or equal to the set intermediate temperature threshold, the starting step temperature is the set third temperature. The first temperature is greater than the second temperature, and the second temperature is greater than the third temperature. Specifically, in this embodiment, the maximum temperature threshold and the intermediate temperature threshold are set to 15℃ and 10℃, respectively; the first temperature, the second temperature, and the third temperature are 10℃, 8℃, and 5℃, respectively, that is: like but ; like but ; like but ; in, The core temperature of the fruit to be preserved; This is the initial step temperature.

[0044] Different quality correction coefficients are set for different quality grades; the weight of the fruit to be preserved is divided by the set standard weight to obtain the normalized weight; the normalized weight is multiplied by the set unit correction time to obtain the weight correction time; the set base step maintenance time is added to the weight correction time; the sum is multiplied by the set quality correction coefficient to obtain the step maintenance time. The formula is as follows:

[0045] in, The duration of the staircase maintenance; The basic staircase maintenance time is set to 1 hour in this embodiment; The unit correction time is set to 0.3 hours in this embodiment; This refers to the weight of the fruit to be preserved. The standard weight set in this example is 500g; The set quality correction factor, quality level When the digits are 1, 2, or 3, They were set to 0.9, 1.0, and 1.1 respectively.

[0046] It should be noted that in this embodiment, the initial step temperature is set according to the core temperature, and the step maintenance time is adjusted in combination with weight and quality grade, so that the cooling start point and cooling rhythm are more in line with the actual thermal state and quality requirements of the fruit.

[0047] In this preferred embodiment, the step-by-step cooling of the ice-cooling chamber based on the initial step temperature and the step duration specifically involves: The target temperature of the first stepped ice chamber is the initial stepped temperature. The target temperature decreases by a set unit temperature for each stepped temperature until the target temperature of the stepped temperature reaches the set minimum temperature. In this embodiment, the minimum temperature is set to -1℃, and the unit temperature is set to 1℃, for example... The target temperatures for each step are: 5℃, 4℃, 3℃, 2℃, 1℃, 0℃, and -1℃.

[0048] Each step uses a PI controller to control the compressor frequency and damper duty cycle of the ice-cooling chamber, stabilizing the temperature within the corresponding temperature range. The upper limit of this temperature range is the sum of the target temperature of the step and a set second margin, while the lower limit is the difference between the target temperature and the set second margin. Specifically, in this embodiment, the second margin is set to 0.5℃, meaning the temperature of the ice-cooling chamber is stabilized within a certain range. Within.

[0049] Furthermore, at each step, after each set first cycle, the core temperature of the fruit to be preserved is detected. If the core temperature of the fruit to be preserved for a set number of consecutive first weeks is less than or equal to the difference between the target temperature of the step and the set third margin, or if the duration of the current step is greater than or equal to a set proportion of the step maintenance time and the core temperature of the fruit to be preserved is within the temperature range corresponding to the step, then the current step ends and the next step begins. Otherwise, the next step begins after the duration of the current step equals the step maintenance time, until all steps are completed; where the third margin is less than the second margin. Specifically, in this embodiment, the first cycle is set to 10 minutes, the quantity is set to 2, the ratio is set to 80%, and the third margin is 0.3℃, that is: Condition A: And this state lasts for more than 20 minutes; Condition B: and ; in, The duration of the current step; If condition A or condition B is met, proceed directly to the next step; if all steps have been completed, end the cooling process. Otherwise... When the time is up, proceed to the next step. If all steps have been completed, the cooling process ends.

[0050] It should be noted that this embodiment uses a step-by-step approach to gradually decrease the target temperature, and within each step, the switching between steps is controlled by both the fruit core temperature feedback and the duration of the cooling process. This prevents the cooling from being too fast or too slow, and improves the stability and efficiency of the cooling process.

[0051] In this preferred embodiment, maintaining the current ice-temperature chamber temperature until the set maximum extension time has elapsed, or until the core temperature of the fruit to be preserved is still greater than the sum of the lower limit of the corresponding target ice-temperature range and the set first margin, specifically means: Maintain the current temperature of the ice chamber, and check the core temperature of the fruit to be preserved once every second set cycle. If the core temperature of the fruit to be preserved is less than or equal to the sum of the lower limit of the corresponding target ice temperature range and the set first margin, then control the ice chamber to maintain the ice temperature. If, after the set maximum extension time, the core temperature of the fruit to be preserved is still greater than the sum of the lower limit of the corresponding target ice temperature range and the set first margin, then repeat S3 (i.e., check the current core temperature of the fruit to be preserved; if the core temperature of the fruit to be preserved is greater than the set ice temperature threshold, then control the ice chamber to cool down stepwise again; otherwise, control the ice chamber to maintain the ice temperature).

[0052] Specifically, in this embodiment, the second cycle is set to 30 minutes, the first margin is set to 0.2°C, and the maximum extension time is set to 2 hours.

[0053] The target ice temperature ranges for different quality grades set in this embodiment are as follows: when At that time, the target ice temperature range is ; when At that time, the target ice temperature range is ; when At that time, the target ice temperature range is .

[0054] It should be noted that in this embodiment, if the core temperature is still too high after the step cooling process, it is determined whether the step cooling process needs to be restarted to avoid affecting the preservation effect due to insufficient cooling in one step.

[0055] In this preferred embodiment, the adaptive correction of the target ice temperature range for different quality grades based on the current storage period of the fruit to be preserved specifically involves: Multiply the storage period of the fruit to be preserved by the set storage time correction factor. If the result of the multiplication is greater than the set maximum correction offset, then the storage period correction offset is equal to the set maximum correction offset; otherwise, the storage period correction offset is equal to the multiplication result. Specifically, the storage time correction factor set in this embodiment is 0.1. / day, the maximum correction offset is set to Storage period correction offset The formula is:

[0056] in, Storage period, in days.

[0057] If the sum of the upper limit of the target ice temperature range for each quality level and the storage period correction offset is less than or equal to the freezing point temperature, then the upper limit of the target ice temperature range for the corresponding quality level will be adaptively corrected. It equals the sum of the upper limit of the target ice temperature range for the corresponding quality level before adaptive correction and the storage period correction offset; otherwise, it equals the upper limit of the target ice temperature range for the corresponding quality level after adaptive correction. It equals the freezing point temperature (i.e., 0°C); If the sum of the lower limit of the target ice temperature range for each quality level and the storage period correction offset is less than or equal to the difference between the freezing point temperature and the fourth margin, then the lower limit of the target ice temperature range after adaptive correction for the corresponding quality level is... It equals the sum of the lower limit of the target ice temperature range for the corresponding quality level before adaptive correction and the storage period correction offset; otherwise, it is the lower limit of the target ice temperature range after adaptive correction for the corresponding quality level. It is equal to the difference between the freezing point temperature and the fourth margin; in this embodiment, the fourth margin is set to 0.2℃.

[0058] It should be noted that in this embodiment, the upper and lower limits of the target ice temperature range are adaptively adjusted according to the storage period, so that the ice temperature control is dynamically optimized as the fruit is stored for a period of time, thus preventing the quality from deteriorating later.

[0059] In this preferred embodiment, the storage period of the fruit to be preserved is specifically: like Figure 4 As shown, when the fruit to be preserved is placed in the ice-temperature room, the current storage period of the fruit to be preserved is 0. When the time of day reaches the set time, if the ice-temperature room is controlled to maintain the ice temperature, the storage period is increased by 1; otherwise, the current storage period is maintained. It should be noted that the storage duration is stored in non-volatile memory. Each time the storage duration is updated, the correlation coefficients related only to the storage duration in this embodiment are also updated (specifically including: storage duration correction offset). and subsequent opening duration correction coefficient. and vacuum pump power correction factor ).

[0060] Specifically, the time set in this embodiment is 02:00 AM (avoiding user operation time).

[0061] When the storage period exceeds the set first storage period threshold, an early warning is issued. When the storage period exceeds the set second storage period threshold, the control of the ice and cold chamber to maintain the ice temperature is forcibly terminated, and the temperature of the ice and cold chamber is maintained at the set refrigeration temperature, and an alarm is triggered.

[0062] Specifically, in this embodiment, the first storage period threshold is set to 7 days, the second storage period threshold is set to 10 days, and the refrigeration temperature is set to 2°C.

[0063] It should be noted that this embodiment provides an early warning or forcibly exits ice-temperature control and switches to refrigeration when the storage period reaches the threshold, which can prevent the fruit from spoiling due to prolonged storage and improve the safety of use.

[0064] In this preferred embodiment, the step of activating the compressor, damper, and vacuum pump for cooling specifically involves: The compressor is turned on at a set frequency, and the damper opens and closes in a cyclical manner. Specifically, the frequency set in this embodiment is within the range of 40-60Hz; The compressor power is obtained. If the compressor power is less than the set light load power threshold (i.e., the current load is light), the vacuum pump and the damper will open and close synchronously. Otherwise (i.e., the current load is heavy), the vacuum pump will always be on during cooling. The opening and closing times of the damper in each cycle, as well as the power of the vacuum pump, are calculated based on the weight and storage period of the fruit to be preserved. Until the core temperature of the fruit to be preserved is less than or equal to the lower limit of the corresponding adaptively corrected target ice temperature range, the compressor, damper and vacuum pump are turned off, and the process returns to the step of adaptively correcting the target ice temperature range for different quality grades based on the current storage period of the fruit to be preserved (i.e., repeating S5).

[0065] In this embodiment, the coordinated action of the vacuum pump and damper is adjusted according to the compressor power status during refrigeration, and the cycle time and pump power are calculated based on weight and storage period to balance refrigeration efficiency and power.

[0066] In this preferred embodiment, the opening and closing durations of the damper in each cycle, as well as the power of the vacuum pump, are calculated based on the weight and storage period of the fruit to be preserved. Specifically: Subtract the product of the set first storage period correction coefficient and the storage period from 1. If the result of the subtraction is greater than the set lower limit of the opening duration correction, then the opening duration correction coefficient is equal to the subtraction result; otherwise, the opening duration correction coefficient is equal to the set lower limit of the opening duration correction. Add the product of the set opening weight correction coefficient and the normalized weight to the set base opening duration, and multiply the sum by the opening duration correction coefficient to obtain the opening duration. The shutdown duration is obtained by subtracting the set shutdown weight correction factor and the normalized weight from the set base shutdown duration, and the shutdown duration is greater than or equal to 0. Activation time and shutdown duration The formula is:

[0067] in, The correction factor for the first storage period is set to 0.025 / day in this embodiment; To ensure the lower limit for enabling duration correction is met, this embodiment sets it to 0.8; The basic activation time is set to 15 minutes in this embodiment; The set start-up weight correction factor is set to 2.5 minutes in this embodiment; The base shutdown duration is set to 12 minutes in this embodiment; The set shut-off weight correction factor is set to 1.2 minutes in this embodiment; To adjust the activation duration; If the weight of the fruit to be preserved is less than the set first weight, the basic power of the vacuum pump is the first power. If the weight of the fruit to be preserved is greater than or equal to the set first weight and less than the set second weight, the basic power of the vacuum pump is the second power. If the weight of the fruit to be preserved is greater than or equal to the set second weight, the basic power of the vacuum pump is the third power. The first power is less than the second power, and the second power is less than the third power. Specifically, the first weight and the second weight are 300g and 800g respectively; the first power, the second power, and the third power are 30%, 50%, and 100% of the rated power respectively.

[0068] Subtract the product of the set second storage period correction factor and the storage period from 1. If the result of the subtraction is greater than the set lower limit of vacuum pump power correction, then the vacuum pump power correction factor is equal to the result of the subtraction; otherwise, the vacuum pump power correction factor is equal to the set lower limit of vacuum pump power correction. Multiply the base power of the vacuum pump by the vacuum pump power correction factor to obtain the power of the vacuum pump. Vacuum pump power The formula is:

[0069] in, The second storage period correction factor is set to 0.02 / day in this embodiment; The lower limit for the set vacuum pump power correction is set to 0.7 in this embodiment; This is the vacuum pump power correction factor.

[0070] It should be noted that in this embodiment, the opening and closing times of the damper and the power of the vacuum pump are adjusted according to the weight and storage period during refrigeration, so that the refrigeration capacity is automatically adapted to the fruit loading and storage time.

[0071] In this preferred embodiment, the step of activating the vacuum pump for dehumidification specifically involves: During dehumidification, the vacuum pump operates at its first power. After starting the third cycle, the vacuum pump is turned off, and the process returns to the step of adaptively correcting the target ice temperature range for different quality grades based on the current storage period of the fruit to be preserved (i.e., repeating S5).

[0072] Specifically, the third cycle set in this embodiment is 3 minutes.

[0073] It should be noted that in this embodiment, the dehumidification is performed at a fixed low power setting and then stopped after a set period, which can quickly reduce excessive humidity and avoid fruit dehydration caused by prolonged dehumidification.

[0074] The compressor, damper, and vacuum pump are all shut down, specifically: If the compressor, damper, and vacuum pump were previously on, and it is determined at the current moment that the compressor, damper, and vacuum pump are all off, then the compressor and damper will immediately close. If the weight of the fruit to be preserved is greater than or equal to the set second weight, then the vacuum pump will continue to operate for the set extended time before closing; otherwise, it will close immediately.

[0075] Specifically, the extension time is set at 5 minutes.

[0076] It should be noted that in this embodiment, the decision on whether to delay shutting down the vacuum pump is based on the weight of the fruit. When the fruit is heavier, the delay is extended to suppress the rise in humidity.

[0077] In this preferred embodiment, when maintaining the ice temperature, if the refrigerator door is detected to be open, all outputs of the compressor, damper, and vacuum pump are stopped. After the ice temperature door is closed again, the weight of the fruit to be preserved is detected again. After the door is closed, the weight sensor inside the refrigerator is read again to obtain the weight. If the user changes the batch of the fruit to be preserved at this time, the user selects "Batch Change" on the refrigerator operation interface and repeats the above steps starting from step S1.

[0078] It should be noted that this embodiment uses door opening detection to prevent cold air loss or misoperation during door opening.

[0079] In Example 2 of the present invention, a batch of 600g of strawberries (semi-ripe, L=2) with an initial temperature of 18°C ​​were placed in the ice compartment of a refrigerator and the steps of the method described in Example 1 of the present invention were performed. Initial read W =600g, =18℃, L =2, D =0. W >10g, >5℃, control the temperature of the ice-cooled greenhouse in stages.

[0080] because but ; =1.36 hours. Each step takes approximately 1.5 hours, but there are step variations. Achieving the target ahead of schedule (Condition A) and advancing to the next tier ahead of time takes approximately 12 hours in total. After completion... The temperature was lowered to -0.8℃ (which meets the requirement of being below the target ice temperature range of -0.6℃ + first margin of 0.2℃ = -0.4℃), and the ice temperature in the ice chamber was controlled to maintain the ice temperature.

[0081] Maintaining ice temperature in the ice-cooling chamber: based on the target range (No storage offset). Start refrigeration when the temperature is above -0.3℃. The compressor, damper (Ton=18min, Toff=10.6min), and vacuum pump (start and stop simultaneously with the damper) will run until... The temperature drops below -0.6°C. The process is repeated to maintain the ice temperature.

[0082] 2:00 AM every day D The temperature will increase gradually. On the 7th day, a warning will be issued and the display screen will indicate "It is recommended to consume as soon as possible"; on the 10th day, the food will be forcibly removed from the ice temperature setting and switched to 2°C refrigeration with an alarm sounding.

[0083] Embodiment 3 of the present invention proposes an intelligent preservation system based on the method described in Embodiment 1 of the present invention, comprising: a control status judgment module for the ice-temperature chamber, a step-down cooling module for the ice-temperature chamber, and a module for maintaining the ice temperature in the ice-temperature chamber, specifically: Ice compartment temperature control status judgment module: After placing the fruit to be preserved into the ice compartment of the refrigerator and setting the quality grade of the fruit to be preserved, when it is detected that the weight of the fruit to be preserved is greater than the set weight threshold, the module detects the core temperature of the fruit to be preserved; if the core temperature of the fruit to be preserved is greater than the set ice temperature threshold, the module controls the ice compartment to cool down in stages; otherwise, the module controls the ice compartment to maintain the ice temperature. The ice-cooling chamber stepped cooling module is used to set the initial stepped temperature and the stepped maintenance time based on the weight, core temperature, and quality grade of the fruit to be preserved. Based on the initial stepped temperature and the stepped maintenance time, it controls the stepped cooling of the ice-cooling chamber. After the stepped cooling is completed, it sets the target ice temperature range for different quality grades and determines whether the core temperature of the fruit to be preserved is greater than the sum of the lower limit of the corresponding target ice temperature range and the set first margin. If not, it controls the ice-cooling chamber to maintain the ice temperature; if so, it maintains the current ice-cooling chamber temperature until the set maximum extension time has elapsed, or until the core temperature of the fruit to be preserved is still greater than the sum of the lower limit of the corresponding target ice temperature range and the set first margin. The ice temperature control module for maintaining the ice temperature in the ice-temperature chamber is used to adaptively adjust the target ice temperature range for different quality grades based on the current storage period of the fruit to be preserved. If the core temperature of the fruit to be preserved is greater than the upper limit of the corresponding adaptively adjusted target ice temperature range, the compressor, damper, and vacuum pump are turned on for cooling. If the core temperature of the fruit to be preserved is less than or equal to the lower limit of the corresponding adaptively adjusted target ice temperature range, it is determined whether the current relative humidity is greater than the set humidity threshold. If so, the vacuum pump is turned on for dehumidification; otherwise, the compressor, damper, and vacuum pump are all turned off.

[0084] It should be noted that this embodiment divides the intelligent preservation method into modules to facilitate the automated operation of the intelligent preservation method.

[0085] Embodiment 4 of the present invention proposes an intelligent preservation refrigerator that integrates the intelligent preservation system described in Embodiment 3 of the present invention.

[0086] like Figure 5 As shown, the refrigerator includes a temperature compartment, a refrigeration compartment, and a freezer compartment; a display screen is also installed on the surface of the refrigerator; the refrigerator interior includes a compressor, a damper, and an air duct. like Figure 6 As shown, the ice chamber also includes an ice temperature drawer, a weight sensor, a vacuum pump, a temperature sensor, a humidity sensor, an infrared temperature sensor, and a heater, specifically: Ice-temperature drawer: This is an independent, sealed cavity, a drawer-type fruit and vegetable box built into an ice-temperature compartment.

[0087] Heater: Located at the top of the ice chamber, used to heat the cold air. The heater operates at a certain opening rate.

[0088] Vacuum pump: Miniature diaphragm vacuum pump, with the suction port connected to the ice-temperature chamber and the exhaust port leading to the outside.

[0089] Weight sensor: A thin-film pressure sensor is placed at the bottom of the drawer to detect the weight of the fruit to be preserved.

[0090] Infrared temperature sensor: Installed on the top of the ice-cooling chamber, aligned with the drawer-type fruit and vegetable box, to detect the core temperature of the fruit to be preserved.

[0091] Temperature sensor: Installed on the side wall of the ice chamber to detect the temperature of the ice chamber.

[0092] Humidity sensor: Installed on the side wall of the ice chamber to detect the relative humidity of the ice chamber.

[0093] It should be noted that this embodiment integrates an intelligent preservation system into the refrigerator, enabling the refrigerator to have adaptive ice temperature control capabilities, thereby improving the preservation effect of fruit storage and user convenience.

[0094] This disclosure can be a system, method, and / or computer program product. A computer program product may include a computer-readable storage medium having computer-readable program instructions loaded thereon for causing a processor to implement various aspects of this disclosure.

[0095] Computer-readable storage media can be tangible devices capable of holding and storing instructions for use by an instruction execution device. Computer-readable storage media can be, for example—but not limited to—electrical storage devices, magnetic storage devices, optical storage devices, electromagnetic storage devices, semiconductor storage devices, or any suitable combination of the foregoing. More specific examples (a non-exhaustive list) of computer-readable storage media include: portable computer disks, hard disks, random access memory (RAM), read-only memory (ROM), erasable programmable read-only memory (EPROM or flash memory), static random access memory (SRAM), portable compact disc read-only memory (CD-ROM), digital multifunction disc (DVD), memory sticks, floppy disks, mechanical encoding devices, such as punch cards or recessed protrusions storing instructions thereon, and any suitable combination of the foregoing. The computer-readable storage media used herein are not to be construed as transient signals themselves, such as radio waves or other freely propagating electromagnetic waves, electromagnetic waves propagating through waveguides or other transmission media (e.g., light pulses through fiber optic cables), or electrical signals transmitted through wires.

[0096] The computer-readable program instructions described herein can be downloaded from computer-readable storage media to various computing / processing devices, or downloaded via a network, such as the Internet, local area network, wide area network, and / or wireless network, to an external computer or external storage device. The network may include copper transmission cables, fiber optic transmission, wireless transmission, routers, firewalls, switches, gateway computers, and / or edge servers. A network adapter card or network interface in each computing / processing device receives the computer-readable program instructions from the network and forwards them to the computer-readable storage media in the respective computing / processing device.

[0097] Computer program instructions used to perform the operations of this disclosure may be assembly instructions, instruction set architecture (ISA) instructions, machine instructions, machine-dependent instructions, microcode, firmware instructions, status setting data, or source code or object code written in any combination of one or more programming languages, including object-oriented programming languages ​​such as Smalltalk, C++, etc., and conventional procedural programming languages ​​such as the "C" language or similar programming languages. The computer-readable program instructions may execute entirely on the user's computer, partially on the user's computer, as a standalone software package, partially on the user's computer and partially on a remote computer, or entirely on a remote computer or server. In cases involving a remote computer, the remote computer may be connected to the user's computer via any type of network—including a local area network (LAN) or a wide area network (WAN)—or may be connected to an external computer (e.g., via the Internet using an Internet service provider). In some embodiments, electronic circuitry, such as programmable logic circuitry, field-programmable gate arrays (FPGAs), or programmable logic arrays (PLAs), is personalized by utilizing the status information of the computer-readable program instructions to implement various aspects of this disclosure.

[0098] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and not to limit it. Although the present invention has been described in detail with reference to the above embodiments, those skilled in the art should understand that modifications or equivalent substitutions can still be made to the specific implementation of the present invention. Any modifications or equivalent substitutions that do not depart from the spirit and scope of the present invention should be covered within the protection scope of the claims of the present invention.

Claims

1. A smart preservation method, characterized in that, include: Place the fruit to be preserved in the freezer compartment of the refrigerator and set the quality level of the fruit to be preserved; When the weight of the fruit to be preserved is detected to be greater than the set weight threshold, the core temperature of the fruit to be preserved is detected. If the core temperature of the fruit to be preserved is greater than the set ice temperature threshold, the ice chamber is controlled to cool down in stages; otherwise, the ice chamber is controlled to maintain the ice temperature. The controlled ice-cooling chamber is cooled in stages as follows: An initial stage temperature and a stage duration are set based on the weight, core temperature, and quality grade of the fruit to be preserved. The ice-cooling chamber is then cooled in stages based on the initial stage temperature and stage duration. After the stage cooling is completed, target ice-temperature ranges for different quality grades are set. It is then determined whether the core temperature of the fruit to be preserved is greater than the sum of the lower limit of the corresponding target ice-temperature range and the set first margin. If not, the ice-cooling chamber is maintained at the ice temperature. If so, the current ice-cooling chamber temperature is maintained until the set maximum extension time has elapsed, or until the core temperature of the fruit to be preserved is still greater than the sum of the lower limit of the corresponding target ice-temperature range and the set first margin. The ice temperature in the controlled ice chamber is maintained by: adaptively adjusting the target ice temperature range for different quality grades based on the current storage period of the fruit to be preserved; if the core temperature of the fruit to be preserved is greater than the upper limit of the corresponding adaptively adjusted target ice temperature range, then the compressor, damper and vacuum pump are turned on for cooling. If the core temperature of the fruit to be preserved is less than or equal to the lower limit of the corresponding adaptively corrected target ice temperature range, then it is determined whether the current relative humidity is greater than the set humidity threshold. If so, the vacuum pump is turned on for dehumidification; otherwise, the compressor, damper, and vacuum pump are all turned off.

2. The intelligent preservation method according to claim 1, characterized in that: The initial step temperature and the step maintenance time are set based on the weight, core temperature, and quality grade of the fruit to be preserved, specifically as follows: If the core temperature of the fruit to be preserved is greater than the set maximum temperature threshold, the starting step temperature is the set first temperature; if the core temperature of the fruit to be preserved is greater than the set intermediate temperature threshold and less than or equal to the set maximum temperature threshold, the starting step temperature is the set second temperature; if the core temperature of the fruit to be preserved is greater than the set ice temperature threshold and less than or equal to the set intermediate temperature threshold, the starting step temperature is the set third temperature. The first temperature is greater than the second temperature, and the second temperature is greater than the third temperature. Different quality correction coefficients are set for different quality grades; the weight of the fruit to be preserved is divided by the set standard weight to obtain the normalized weight, the normalized weight is multiplied by the set unit correction time to obtain the weight correction time, the set basic step maintenance time is added to the weight correction time, and the sum is multiplied by the set quality correction coefficient to obtain the step maintenance time.

3. The intelligent preservation method according to claim 1, characterized in that: The step-down cooling of the ice-cooling chamber based on the initial step temperature and the step duration is specifically as follows: The target temperature of the first stepped ice chamber is the initial stepped temperature. The target temperature decreases by a set unit temperature for each stepped temperature until the target temperature of the stepped temperature reaches the set minimum temperature. Each step uses a PI controller to control the compressor frequency and damper duty cycle of the ice chamber to stabilize the temperature of the ice chamber within the corresponding temperature range of the step. The upper limit of the corresponding temperature range of the step is the sum of the target temperature of the step and the set second margin, and the lower limit of the corresponding temperature range of the step is the difference between the target temperature of the step and the set second margin. Furthermore, at each step, after each set first cycle, the core temperature of the fruit to be preserved is detected. If the core temperature of the fruit to be preserved for a set number of consecutive first weeks is less than or equal to the difference between the target temperature of the step and the set third margin, or if the duration of the current step is greater than or equal to a set proportion of the step maintenance time and the core temperature of the fruit to be preserved is within the temperature range corresponding to the step, then the current step ends and the next step begins. Otherwise, the next step begins after the duration of the current step equals the step maintenance time, until all steps are completed; where the third margin is less than the second margin.

4. The intelligent preservation method according to claim 1, characterized in that: Maintaining the current ice-temperature chamber temperature until the set maximum extension time has elapsed, or until the core temperature of the fruit to be preserved is still greater than the sum of the lower limit of the corresponding target ice-temperature range and the set first margin, specifically means: Maintain the current temperature of the ice-cooling chamber, and check the core temperature of the fruit to be preserved every second set cycle. If the core temperature of the fruit to be preserved is less than or equal to the sum of the lower limit of the corresponding target ice temperature range and the set first margin, then control the ice-cooling chamber to maintain the ice temperature. If, after the set maximum extension time, the core temperature of the fruit to be preserved is still greater than the sum of the lower limit of the corresponding target ice temperature range and the set first margin, then check the current core temperature of the fruit to be preserved. If the core temperature of the fruit to be preserved is greater than the set ice temperature threshold, then control the ice-cooling chamber to cool down in stages again; otherwise, control the ice-cooling chamber to maintain the ice temperature.

5. The intelligent preservation method according to claim 1, characterized in that: The adaptive correction of the target ice temperature range for different quality grades based on the current storage period of the fruit to be preserved is specifically as follows: Multiply the storage period of the fruit to be preserved by the set storage time correction factor. If the result of the multiplication is greater than the set maximum correction offset, then the storage period correction offset is equal to the set maximum correction offset; otherwise, the storage period correction offset is equal to the multiplication result. If the sum of the upper limit of the target ice temperature range for each quality level and the storage period correction offset is less than or equal to the freezing point temperature, then the upper limit of the target ice temperature range after adaptive correction for the corresponding quality level is equal to the sum of the upper limit of the target ice temperature range for the corresponding quality level and the storage period correction offset; otherwise, the upper limit of the target ice temperature range after adaptive correction for the corresponding quality level is equal to the freezing point temperature. If the sum of the lower limit of the target ice temperature range for each quality level and the storage period correction offset is less than or equal to the difference between the freezing point temperature and the fourth margin, then the lower limit of the target ice temperature range after adaptive correction for the corresponding quality level is equal to the sum of the lower limit of the target ice temperature range for the corresponding quality level and the storage period correction offset; otherwise, the lower limit of the target ice temperature range after adaptive correction for the corresponding quality level is equal to the difference between the freezing point temperature and the fourth margin.

6. The intelligent preservation method according to claim 4, characterized in that: The storage period for the fruit currently awaiting preservation is as follows: When fruits to be preserved are placed in the ice-temperature room, the current storage period of the fruits to be preserved is 0. When the time of day reaches the set time, if the ice-temperature room is controlled to maintain the ice temperature, the storage period is increased by 1; otherwise, the current storage period is maintained. When the storage period exceeds the set first storage period threshold, an early warning is issued. When the storage period exceeds the set second storage period threshold, the control of the ice and cold chamber to maintain the ice temperature is forcibly terminated, and the temperature of the ice and cold chamber is maintained at the set refrigeration temperature, and an alarm is triggered.

7. The intelligent preservation method according to claim 2, characterized in that: The process of activating the compressor, damper, and vacuum pump for cooling specifically involves: The compressor is turned on at a set frequency, and the damper opens and closes in a cyclical manner. Obtain the compressor power. If the compressor power is less than the set light load power threshold, the vacuum pump and damper will open and close synchronously. Otherwise, the vacuum pump will always be on during cooling. The opening and closing times of the damper in each cycle, as well as the power of the vacuum pump, are calculated based on the weight and storage period of the fruit to be preserved. Once the core temperature of the fruit to be preserved is less than or equal to the lower limit of the corresponding adaptively corrected target ice temperature range, the compressor, damper, and vacuum pump are turned off, and the process returns to the step of adaptively correcting the target ice temperature range for different quality grades based on the current storage period of the fruit to be preserved.

8. The intelligent preservation method according to claim 7, characterized in that: The opening and closing times of the damper in each cycle, as well as the power of the vacuum pump, are calculated based on the weight and storage period of the fruit to be preserved. Specifically: Subtract the product of the set first storage period correction coefficient and the storage period from 1. If the result of the subtraction is greater than the set lower limit of the opening duration correction, then the opening duration correction coefficient is equal to the subtraction result; otherwise, the opening duration correction coefficient is equal to the set lower limit of the opening duration correction. Add the product of the set opening weight correction coefficient and the normalized weight to the set base opening duration, and multiply the sum by the opening duration correction coefficient to obtain the opening duration. The shutdown duration is obtained by subtracting the set shutdown weight correction factor and the normalized weight from the set base shutdown duration, and the shutdown duration is greater than or equal to 0. If the weight of the fruit to be preserved is less than the set first weight, the base power of the vacuum pump is the first power. If the weight of the fruit to be preserved is greater than or equal to the set first weight and less than the set second weight, the base power of the vacuum pump is the second power. If the weight of the fruit to be preserved is greater than or equal to the set second weight, the base power of the vacuum pump is the third power. The first power is less than the second power, and the second power is less than the third power. Subtract the product of the set second storage period correction coefficient and the storage period from 1. If the result of the subtraction is greater than the set lower limit of vacuum pump power correction, the vacuum pump power correction coefficient is equal to the result of the subtraction. Otherwise, the vacuum pump power correction coefficient is equal to the set lower limit of vacuum pump power correction. Multiply the base power of the vacuum pump by the vacuum pump power correction coefficient to obtain the power of the vacuum pump.

9. The intelligent preservation method according to claim 8, characterized in that: The process of turning on the vacuum pump for dehumidification specifically involves: During dehumidification, the vacuum pump operates at its first power. After starting the set third cycle, the vacuum pump is turned off, and the process returns to the step of adaptively correcting the target ice temperature range for different quality grades based on the current storage period of the fruit to be preserved.

10. The intelligent preservation method according to claim 8, characterized in that: The compressor, damper, and vacuum pump are all shut down, specifically: If the compressor, damper, and vacuum pump were previously on, and it is determined at the current moment that the compressor, damper, and vacuum pump are all off, then the compressor and damper will immediately close. If the weight of the fruit to be preserved is greater than or equal to the set second weight, then the vacuum pump will continue to operate for the set extended time before closing; otherwise, it will close immediately.

11. The intelligent preservation method according to claim 8, characterized in that: When maintaining the ice temperature, if the ice chamber door is detected to be open, all outputs of the compressor, damper, and vacuum pump are stopped, and the weight of the fruit to be preserved is detected again after the ice chamber door is closed again.

12. An intelligent preservation system based on the method of any one of claims 1-11, comprising: The ice-temperature chamber control status judgment module, the ice-temperature chamber stepped cooling control module, and the ice-temperature chamber temperature maintenance control module are characterized by: Ice compartment temperature control status judgment module: After placing the fruit to be preserved into the ice compartment of the refrigerator and setting the quality grade of the fruit to be preserved, when it is detected that the weight of the fruit to be preserved is greater than the set weight threshold, the module detects the core temperature of the fruit to be preserved; if the core temperature of the fruit to be preserved is greater than the set ice temperature threshold, the module controls the ice compartment to cool down in stages; otherwise, the module controls the ice compartment to maintain the ice temperature. The ice-cooling chamber stepped cooling module is used to set the initial stepped temperature and the stepped maintenance time based on the weight, core temperature, and quality grade of the fruit to be preserved. Based on the initial stepped temperature and the stepped maintenance time, it controls the stepped cooling of the ice-cooling chamber. After the stepped cooling is completed, it sets the target ice temperature range for different quality grades and determines whether the core temperature of the fruit to be preserved is greater than the sum of the lower limit of the corresponding target ice temperature range and the set first margin. If not, it controls the ice-cooling chamber to maintain the ice temperature; if so, it maintains the current ice-cooling chamber temperature until the set maximum extension time has elapsed, or until the core temperature of the fruit to be preserved is still greater than the sum of the lower limit of the corresponding target ice temperature range and the set first margin. The ice temperature control module for maintaining the ice temperature in the ice-temperature chamber is used to adaptively adjust the target ice temperature range for different quality grades based on the current storage period of the fruit to be preserved. If the core temperature of the fruit to be preserved is greater than the upper limit of the corresponding adaptively adjusted target ice temperature range, the compressor, damper, and vacuum pump are turned on for cooling. If the core temperature of the fruit to be preserved is less than or equal to the lower limit of the corresponding adaptively adjusted target ice temperature range, it is determined whether the current relative humidity is greater than the set humidity threshold. If so, the vacuum pump is turned on for dehumidification; otherwise, the compressor, damper, and vacuum pump are all turned off.

13. A smart refrigerator for food preservation, characterized in that, Integrate the intelligent preservation system described in claim 12.

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