Intelligent cold supplement control method and system before air-cooled refrigerator defrosting

Abstract

This invention provides an intelligent cooling control method and system for a frost-free refrigerator before defrosting. The method is executed after a preset defrosting trigger condition is met and before the defrosting heater is actually activated. It includes a pre-defrosting strong cooling and cold storage stage, which includes: controlling the refrigerator compartment to maintain a cooling state and shifting the target control temperature of the refrigerator compartment downward by a first offset; shifting the stop temperature threshold of the freezer compartment downward by a second offset, wherein the second offset is greater than the first offset; controlling the inverter compressor to run continuously at a first frequency higher than the conventional cooling frequency; and terminating the pre-defrosting strong cooling and cold storage stage and activating the defrosting heater when the actual temperature of the freezer compartment reaches the downwardly shifted stop temperature threshold, or when the duration of the pre-defrosting strong cooling and cold storage stage reaches a preset maximum strong cooling time threshold, in order to solve the problem of a significant rise in compartment temperature during defrosting affecting food preservation.

Description

Technical Field

[0001] This application relates to the field of refrigeration equipment technology, and in particular to an intelligent cooling control method and system for air-cooled refrigerators before defrosting. Background Technology

[0002] Frost-free refrigerators have become the mainstream in the market due to their advantages such as frost-free operation and rapid cooling. During operation, frost gradually forms on the evaporator surface due to moisture condensation, leading to a decrease in heat exchange efficiency. Therefore, a defrosting process must be initiated periodically to remove the frost. During defrosting, the defrosting heater operates, the refrigerator stops cooling, and the freezer and refrigerator compartments inevitably experience a significant temperature rise due to the intrusion of defrosting heat and the lack of cooling. For frozen foods requiring long-term low-temperature storage, such drastic temperature fluctuations can severely affect their cell structure and preservation quality. Therefore, maintaining stable compartment temperatures throughout the entire defrosting cycle, especially suppressing excessive temperature rises in the freezer compartment, is a pressing technical challenge that needs to be addressed in this field.

[0003] To address the issue of temperature rise in storage compartments caused by defrosting, relevant technologies typically employ a post-defrosting compensatory cooling strategy. Specifically, after the defrosting process concludes, the control system monitors the compartment temperature. If it detects that the temperature exceeds the normal range, it controls the compressor to start operating at a higher frequency, attempting to quickly bring the temperature back to the set value. This approach aims to compensate for heat loss during defrosting through powerful cooling after defrosting, thereby restoring the storage environment as quickly as possible.

[0004] However, the aforementioned post-defrost compensatory cooling solutions exhibit significant lag. Since the freezer temperature has already risen considerably during defrost (often exceeding -6°C, and even approaching or reaching 0°C), restarting high-frequency cooling after defrost, while ultimately lowering the temperature, cannot change the fact that the temperature exceeded the acceptable range during defrost, and the food still suffers from high-temperature damage during this period. Furthermore, relying solely on high-frequency operation after defrost for cooling not only leads to increased compressor noise and a surge in energy consumption, but also fails to fundamentally address the temperature runaway problem during defrost due to the delayed cooling response. Therefore, a control strategy that proactively prevents excessive temperature rise during defrost, rather than relying solely on post-defrost remediation, is urgently needed. Summary of the Invention

[0005] This application provides an intelligent cooling control method and system for air-cooled refrigerators before defrosting, in order to solve the problem of a significant rise in compartment temperature during defrosting affecting food preservation.

[0006] The first aspect of this application provides an intelligent cooling supplementation control method for a frost-free refrigerator before defrosting. The method is executed after a preset defrosting trigger condition is met and before the defrosting heater is actually activated, and includes a pre-defrosting strong cooling and cold storage stage, which includes: Control the refrigerator compartment to maintain a cooling state, and shift the target control temperature of the refrigerator compartment downward by a first offset amount; The shutdown temperature threshold of the freezer compartment is shifted downward by a second offset, wherein the second offset is greater than the first offset; The variable frequency compressor is controlled to operate continuously at a first frequency higher than the conventional refrigeration frequency; When the actual temperature of the freezer reaches the shutdown temperature threshold after downward shift, or when the duration of the pre-defrost strong cooling and cold storage stage reaches the preset maximum strong cooling time threshold, the pre-defrost strong cooling and cold storage stage is terminated and the defrost heater is started.

[0007] The intelligent cooling control method for pre-defrosting of air-cooled refrigerators provided in this application, by performing a strong cooling and cold storage stage before defrosting, shifts the target control temperature of the refrigerator compartment downward by a first offset amount and the freezer compartment shutdown temperature threshold downward by a second offset amount, while controlling the inverter compressor to run continuously at a first frequency higher than the conventional cooling frequency, can increase the total cold storage capacity of the system. The cold storage capacity of the freezer and refrigerator compartments is used to offset the heat intrusion during the defrosting process, thereby improving the temperature rise of the freezer compartment after defrosting and suppressing the peak average temperature of the freezer compartment after defrosting. By setting a dual-condition exit mechanism of temperature and time, the problem of infinite cooling caused by sensor failure or extreme environment can be alleviated, and the environmental adaptability of the system can be improved.

[0008] Optionally, the first offset ranges from 0.3℃ to 1.5℃, and the second offset ranges from 2℃ to 6℃.

[0009] By limiting the value ranges of the first and second offsets, the differentiated cold storage strategy for the refrigerator and freezer compartments can be optimized. This setting allows the freezer compartment to achieve a greater temperature reduction range to enhance cold storage, while maintaining fine-tuning of the refrigerator compartment. This effectively increases the overall cold storage capacity of the system during defrosting, thereby mitigating the temperature rise in the freezer compartment during defrosting and helping to reduce energy consumption and noise during high-frequency operation after defrosting.

[0010] Optionally, the normal shutdown temperature threshold of the freezer compartment is in the range of -19℃ to -21℃, and the downward offset shutdown temperature threshold is in the range of -23℃ to -25℃.

[0011] By setting the freezer compartment's normal shutdown temperature threshold to -19°C to -21°C and then shifting it downwards to -23°C to -25°C, the freezer compartment temperature can be further lowered during the pre-defrost cooling and cold storage phase. This setting increases the cold storage capacity of air and food within the freezer compartment, thereby mitigating the heat intrusion caused by the defrost heater's operation during defrost, improving the rate of temperature recovery after defrost, and helping to maintain the freezer compartment's average maximum temperature at a lower level.

[0012] Optionally, the first frequency ranges from 70 Hz to 120 Hz, and the conventional cooling frequency ranges from 50 Hz to 80 Hz.

[0013] By setting the first frequency to 70 Hz to 120 Hz, which is higher than the conventional refrigeration frequency of 50 Hz to 80 Hz, the compressor's operating speed can be increased during the strong cooling and cold storage phase before defrosting. This setting enhances the refrigerant circulation flow rate of the refrigeration system, thereby improving the heat exchange efficiency of the evaporator, helping to accelerate the rate of temperature drop in the freezer compartment, increasing the system's cold storage capacity per unit time, thus mitigating temperature fluctuations during and after defrosting, and improving the duration of high-frequency compressor operation after defrosting.

[0014] Optionally, the preset maximum cooling time threshold ranges from 120 minutes to 240 minutes.

[0015] By setting the preset maximum cooling time threshold to 120 to 240 minutes, a clear upper limit constraint can be provided for the pre-defrost cooling and cold storage phase. This setting helps alleviate the problem of prolonged ineffective cooling that may occur under conditions such as sensor malfunction or extreme low temperature environments, thereby improving the system's operational stability and environmental adaptability, and reducing unnecessary energy consumption while ensuring that the freezer achieves the expected cold storage effect.

[0016] Optionally, during the pre-defrost cold storage phase, the operation of lowering the target control temperature of the refrigerator compartment and the operation of lowering the shutdown temperature threshold of the freezer compartment are performed simultaneously.

[0017] By simultaneously lowering the target control temperature of the refrigerator compartment and the shutdown temperature threshold of the freezer compartment during the pre-defrost cold storage phase, the cooling processes of the refrigerator and freezer compartments can be coordinated. This setting ensures that both compartments undergo enhanced cold storage within the same time window, improving the overall system response speed and coordination efficiency. This increases the total cold storage capacity before defrost, helps mitigate the temperature rise in the freezer compartment during defrost, and improves the timeliness of cooling recovery after defrost.

[0018] Optionally, the method further includes a recovery control phase after the defrosting heater finishes defrosting, the recovery control phase including: The variable frequency compressor is controlled to start at a second frequency higher than the conventional refrigeration frequency; Prioritize cooling the freezer compartment. Once the freezer compartment temperature returns to below the normal freezing setting temperature, restore normal cooling to the refrigerator compartment.

[0019] By setting a recovery control phase after the defrosting heater finishes defrosting and controlling the inverter compressor to start at a second frequency higher than the conventional cooling frequency, the initial cooling capacity after defrosting can be improved. This setting, combined with a timing strategy that prioritizes cooling the freezer compartment and then restores normal cooling to the refrigerator compartment once its temperature returns to below the conventional freezer setting temperature, helps to accelerate the temperature drop rate of the freezer compartment, mitigate fluctuations caused by the temperature rise in the compartments after defrosting, improve the control of the freezer compartment temperature peak, and balance the temperature stability of the refrigerator compartment.

[0020] Optionally, the defrost heater can be started when the compressor and fan are immediately turned off and the defrost heater is turned on after the pre-defrost cooling and cold storage phase has ended. The conditions for shutting down the defrosting heater are: the evaporator temperature reaches the preset defrost exit temperature threshold, or the defrosting duration reaches the preset maximum defrost time threshold.

[0021] By limiting the activation of the defrost heater to immediately shutting down the compressor and fan and activating the defrost heater after the termination of the pre-defrost cooling and heat storage phase, timely initiation of the defrost process can be ensured, reducing ineffective cooling. Simultaneously, by setting the deactivation conditions for the defrost heater—either the evaporator temperature reaching a preset defrost exit temperature threshold or the defrost duration reaching a preset maximum defrost time threshold—precise control of the defrost termination timing can be achieved. This mitigates the increased energy consumption caused by insufficient or excessive defrosting, improving the controllability and safety of the defrost process.

[0022] Optionally, the preset defrosting trigger conditions include: the compressor's cumulative running time reaching a preset cycle threshold, or the evaporator temperature being lower than a preset frosting temperature threshold.

[0023] By setting the preset defrost trigger condition to either the compressor's cumulative running time reaching a preset cycle threshold or the evaporator temperature falling below a preset frosting temperature threshold, a multi-dimensional defrost judgment basis can be established. This setting helps improve the accuracy of defrost start timing determination, making defrost triggering more consistent with actual frosting conditions. This mitigates the problem of untimely or false defrosting caused by a single judgment condition, while meeting defrosting requirements, and enhances the system's adaptability to different operating environments.

[0024] The second aspect of this application provides an intelligent supplemental cooling control system for a frost-free refrigerator before defrosting, including: a freezer temperature sensor, a refrigerator temperature sensor, an evaporator temperature sensor, a variable frequency compressor, a defrost heater, a refrigeration fan, a main control microcontroller unit, and a refrigerator damper actuator or solenoid valve for controlling the on / off of refrigeration in the refrigerator compartment. The main control microcontroller unit is electrically connected to the freezer temperature sensor, the refrigerator temperature sensor, the evaporator temperature sensor, the variable frequency compressor, the defrost heater, the refrigerator damper actuator or solenoid valve, and the refrigeration fan, respectively. The main control microcontroller unit is configured to execute the intelligent cooling supplement control method for the air-cooled refrigerator before defrosting, as described in the first aspect.

[0025] By constructing a system architecture that includes freezer temperature sensors, refrigerator temperature sensors, evaporator temperature sensors, a variable frequency compressor, a defrost heater, a refrigeration fan, and a main control microcontroller unit, and by incorporating a refrigerator damper actuator or solenoid valve into the control link, the main control microcontroller unit can accurately execute the pre-defrost forced cooling and cold storage methods and the post-defrost recovery control methods. This setup improves the system's ability to independently control the cooling on / off of the refrigerator and freezer compartments, enhances the coordination efficiency between sensor data acquisition and actuator response, thereby helping to mitigate the temperature rise in the freezer compartment during defrosting and improving the overall control accuracy and operational stability of the system.

[0026] As can be seen from the above technical solutions, this application provides an intelligent cooling supplementation control method and system for air-cooled refrigerators before defrosting. The method is executed after the preset defrosting trigger conditions are met and before the defrosting heater is actually started. It includes a pre-defrosting strong cooling and cold storage stage, which includes: controlling the refrigerator compartment to maintain a cooling state and shifting the target control temperature of the refrigerator compartment downward by a first offset; shifting the stop temperature threshold of the freezer compartment downward by a second offset, wherein the second offset is greater than the first offset; controlling the inverter compressor to run continuously at a first frequency higher than the conventional cooling frequency; when the actual temperature of the freezer compartment reaches the downwardly shifted stop temperature threshold, or when the duration of the pre-defrosting strong cooling and cold storage stage reaches the preset maximum strong cooling time threshold, terminating the pre-defrosting strong cooling and cold storage stage and starting the defrosting heater, so as to solve the problem of the significant rise in compartment temperature during defrosting affecting the preservation of food. Attached Figure Description

[0027] To more clearly illustrate the technical solution of this application, the drawings used in the embodiments will be briefly introduced below. Obviously, for those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0028] Figure 1 A flowchart illustrating the intelligent cooling control method for a frost-free refrigerator before defrosting, as provided in an embodiment of this application. Figure 2 A schematic diagram of the structure of an air-cooled refrigerator with a refrigeration damper actuator provided in an embodiment of this application; Figure 3A schematic diagram of the refrigeration system structure of an air-cooled refrigerator with a refrigeration damper provided in an embodiment of this application; Figure 4 A schematic diagram of a wind-cooled refrigerator with an electromagnetic valve provided in an embodiment of this application; Figure 5 A schematic diagram of the refrigeration system structure of an air-cooled refrigerator with a solenoid valve provided in an embodiment of this application; Figure 6 A schematic diagram of the connection of the intelligent supplemental cooling control system with a refrigeration damper provided in this application embodiment; Figure 7 A schematic diagram of the connection of an intelligent cooling supplement control system with a solenoid valve provided in an embodiment of this application; Figure 8 The actual test diagram shows the intelligent cooling replenishment control method before defrosting; Figure 9 This is an actual test diagram of the intelligent cooling control method for air-cooled refrigerators before defrosting, as provided in the embodiments of this application.

[0029] Among them, 110-first compartment; 111-refrigeration compartment temperature sensor; 120-second compartment; 121-freezer compartment temperature sensor; 130-refrigeration damper; 200-inverter compressor; 201-condenser; 202-drier filter; 203-solenoid valve; 204-first capillary tube; 205-first evaporator; 206-second capillary tube; 207-second evaporator; 210-refrigeration fan; 220-freezer fan; 300-defrost heater. Detailed Implementation

[0030] The embodiments will now be described in detail, examples of which are illustrated in the accompanying drawings. When the following description relates to the drawings, unless otherwise indicated, the same numbers in different drawings represent the same or similar elements. The embodiments described below do not represent all embodiments consistent with this application. They are merely examples of systems and methods consistent with some aspects of this application as detailed in the claims.

[0031] It should be noted that the brief descriptions of terms in this application are only for the convenience of understanding the embodiments described below, and are not intended to limit the embodiments of this application. Unless otherwise stated, these terms should be understood in their ordinary and common meaning.

[0032] The terms "first," "second," "third," etc., used in the specification, claims, and accompanying drawings of this application are used to distinguish similar or related objects or entities, and do not necessarily imply a specific order or sequence, unless otherwise specified. It should be understood that such terms are interchangeable where appropriate.

[0033] The terms “comprising” and “having”, and any variations thereof, are intended to cover but not exclusively include, for example, a product or device that includes a range of components is not necessarily limited to all of the components that are clearly listed, but may include other components that are not clearly listed or that are inherent to such product or device.

[0034] To address the issue of significant temperature rises during defrosting affecting food preservation, see [link to relevant documentation]. Figure 1 This application provides a method for intelligent supplemental cooling control before defrosting in a frost-free refrigerator. The method is executed after a preset defrosting trigger condition is met and before the defrosting heater 300 is actually activated. It includes a pre-defrosting strong cooling and cold storage stage, which comprises: S110: Control the refrigerator compartment to maintain a cooling state and shift the target control temperature of the refrigerator compartment downward by a first offset amount.

[0035] It should be understood that the preset defrosting trigger condition is that the cumulative compressor running time reaches a preset time threshold, or the evaporator frost amount is determined to reach the defrosting standard based on the number of times the compartment door is opened and the ambient temperature and humidity detection values. After this condition is met, the refrigerator will not immediately start the defrosting heater 300, but will first enter the pre-defrosting strong cooling and cold storage stage of this embodiment to perform supplemental cooling operation. The downward offset by a first offset amount here refers to lowering the target control temperature of this strong cooling and cold storage stage by the corresponding value compared to the original set target temperature during normal operation of the refrigerator compartment. The first offset amount can be pre-configured according to the refrigerator's volume and the user's daily set temperature, or it can be adaptively adjusted according to the current actual temperature of the refrigerator compartment and the ambient temperature. By lowering the target temperature of the refrigerator compartment in advance for pre-cooling, the overall temperature of the refrigerator compartment can be lowered to a lower level, storing sufficient cold energy. During the subsequent defrosting process, even if cooling is stopped for defrosting, the stored cold energy can slow down the rise in refrigerator compartment temperature, avoiding excessively high temperatures that could affect the preservation effect of food.

[0036] S120: Offset the freezer compartment's shutdown temperature threshold downwards by a second offset amount.

[0037] The second offset is greater than the first offset. It should be understood that after the refrigerator enters the defrosting process, the refrigeration system stops supplying cooling to the evaporator. The heat generated by the defrosting heater 300 will also diffuse to the adjacent freezer compartment. Compared to the refrigerator compartment, the freezer compartment is more sensitive to temperature fluctuations, and the risk to food preservation from temperature rises is greater. Therefore, it is necessary to lower the freezer compartment temperature more significantly in advance and store more cold air to offset the temperature rise during the defrosting process. The original shutdown temperature threshold here refers to the temperature standard at which the inverter compressor 200 will stop operating during the freezer compartment's daily refrigeration cycle. After the downward offset, the freezer compartment needs to operate at a lower temperature than usual before stopping refrigeration, which is equivalent to storing additional cold air in the freezer compartment during the pre-defrosting cooling stage.

[0038] In some embodiments, the first offset ranges from 0.3°C to 1.5°C, and the second offset ranges from 2°C to 6°C.

[0039] Specifically, the first offset is preferably 0.5°C, and the second offset is preferably 4°C.

[0040] By limiting the value ranges of the first and second offsets, the differentiated cold storage strategy for the refrigerator and freezer compartments can be optimized. This setting allows the freezer compartment to achieve a greater temperature reduction range to enhance cold storage, while maintaining fine-tuning of the refrigerator compartment. This effectively increases the overall cold storage capacity of the system during defrosting, thereby mitigating the temperature rise in the freezer compartment during defrosting and helping to reduce energy consumption and noise during high-frequency operation after defrosting.

[0041] In some embodiments, the normal shutdown temperature threshold of the freezer compartment ranges from -19°C to -21°C, and the downward offset shutdown temperature threshold ranges from -23°C to -25°C.

[0042] Specifically, the preferred normal shutdown temperature for the freezer compartment is -19°C, and the shutdown temperature shifted downwards by 4°C is -23°C.

[0043] By setting the freezer compartment's normal shutdown temperature threshold to -19°C to -21°C and then shifting it downwards to -23°C to -25°C, the freezer compartment temperature can be further lowered during the pre-defrost cooling and cold storage phase. This setting increases the cold storage capacity of air and food within the freezer compartment, thereby mitigating the heat intrusion caused by the operation of the defrost heater 300 during defrost, improving the rate of temperature recovery after defrost, and helping to maintain the maximum average freezer compartment temperature at a lower level.

[0044] S130: Controls the inverter compressor 200 to operate continuously at a first frequency higher than the conventional refrigeration frequency.

[0045] It should be understood that the normal cooling frequency refers to the average operating frequency at which the inverter compressor 200 maintains a stable internal temperature in a frost-free refrigerator under normal cooling conditions. A higher first frequency than the normal cooling frequency allows the inverter compressor 200 to output greater cooling capacity, accelerating the temperature drop in the freezer compartment. This allows for more efficient cold storage during the limited preparation time before defrosting begins, preventing insufficient preparation time and inadequate cold storage capacity, and ensuring effective temperature control of the freezer compartment during the subsequent defrosting process.

[0046] In some embodiments, the first frequency ranges from 70 Hz to 120 Hz, and the conventional cooling frequency ranges from 50 Hz to 80 Hz.

[0047] Specifically, the first frequency is preferably in the range of 70 Hz to 85 Hz.

[0048] By setting the first frequency to 70 Hz to 120 Hz, which is higher than the conventional refrigeration frequency of 50 Hz to 80 Hz, the operating speed of the inverter compressor 200 can be increased during the strong cooling and cold storage phase before defrosting. This setting enhances the refrigerant circulation flow rate of the refrigeration system, thereby improving the heat exchange efficiency of the evaporator, helping to accelerate the temperature drop rate of the freezer compartment, increasing the system's cold storage capacity per unit time, thus mitigating temperature fluctuations during and after defrosting, and improving the duration of high-frequency operation of the inverter compressor 200 after defrosting.

[0049] S140: When the actual temperature of the freezer compartment reaches the shutdown temperature threshold after downward offset, or when the duration of the pre-defrost strong cooling and cold storage stage reaches the preset maximum strong cooling time threshold, the pre-defrost strong cooling and cold storage stage is terminated and the defrost heater 300 is started.

[0050] It should be understood that there are two judgment conditions for terminating the strong cooling and cold storage stage before defrosting: The first is temperature judgment. After the high-frequency cooling and cold storage by the inverter compressor 200, the actual temperature of the freezer compartment drops to the pre-adjusted off-limits temperature threshold, which means that sufficient cold storage has been completed to meet the temperature control requirements of the defrosting process. At this time, the strong cooling and cold storage can be terminated directly, and the defrosting heater 300 can be started to begin defrosting. The second is time fallback judgment. If the strong cooling and cold storage has been running for the preset maximum duration, and the actual temperature of the freezer compartment has not dropped to the off-limits temperature threshold, it means that due to factors such as the current ambient temperature and the heat load of the placed items, it is no longer possible to continue cooling and cold storage. In order not to delay the defrosting start time and to ensure that the frost on the evaporator can be dealt with in a timely manner, the strong cooling and cold storage stage also needs to be terminated, and the defrosting heater 300 needs to be started.

[0051] In some embodiments, the preset maximum cooling time threshold ranges from 120 minutes to 240 minutes.

[0052] Specifically, the preset maximum cooling time is preferably 180 minutes.

[0053] By setting the preset maximum cooling time threshold to 120 to 240 minutes, a clear upper limit constraint can be provided for the pre-defrost cooling and cold storage phase. This setting helps alleviate the problem of prolonged ineffective cooling that may occur under conditions such as sensor malfunction or extreme low temperature environments, thereby improving the system's operational stability and environmental adaptability, and reducing unnecessary energy consumption while ensuring that the freezer achieves the expected cold storage effect.

[0054] In some embodiments, during the pre-defrost cold storage phase, the operation of lowering the target control temperature of the refrigerator compartment and the operation of lowering the shutdown temperature threshold of the freezer compartment are performed simultaneously.

[0055] It should be understood that the refrigerator and freezer compartments usually share a single refrigeration system. During the strong cooling and cold storage phase before defrosting, simultaneously lowering the target control temperature of the refrigerator compartment and the shutdown temperature threshold of the freezer compartment allows the system to maintain a continuous cooling state for the same period of time. This not only stores cold energy in advance by lowering the refrigerator compartment temperature to prevent a significant temperature rise in the refrigerator compartment during defrosting, but also completes the cold storage and cooling of the freezer compartment at the same time. There is no need to adjust the two types of temperature parameters in stages, which can maximize the use of refrigeration operation time to improve cold storage efficiency, avoid excessively long single cold storage cycles, and ensure the overall temperature control stability during the defrosting process without additionally extending the refrigeration time and causing unnecessary energy consumption.

[0056] In some embodiments, the method further includes a recovery control phase after the defrosting heater 300 has finished defrosting, the recovery control phase including: The variable frequency compressor 200 is controlled to start at a second frequency higher than the conventional refrigeration frequency.

[0057] Specifically, the second frequency is 60Hz to 90Hz, preferably 70Hz to 80Hz.

[0058] Prioritize cooling the freezer compartment. Once the freezer compartment temperature returns to below the normal freezing setting temperature, restore normal cooling to the refrigerator compartment.

[0059] It should be understood that during the defrosting process, the defrosting heater 300 releases additional heat into the cabinet. After defrosting, the temperatures of both the refrigerator and freezer compartments will rise to some extent. The freezer compartment, in particular, has higher requirements for temperature stability; excessive temperature fluctuations will affect the freezing and preservation effect of stored goods. After defrosting, the inverter compressor 200 is run at a higher frequency to quickly increase the cooling capacity and prioritize the supply of cooling to the freezer compartment. This allows the freezer compartment temperature to quickly drop back to the set temperature range, preventing the freezer compartment from remaining at a high temperature for an extended period, which could affect the quality of stored goods. Once the freezer compartment temperature reaches the target, the refrigerator compartment is then cooled. This approach balances the temperature control needs of both compartments and rationally distributes the cooling capacity, preventing the inverter compressor 200 from running at high frequency for extended periods and consuming excessive energy due to simultaneous cooling of both compartments.

[0060] In some embodiments, the defrost heater 300 is started when the inverter compressor 200 and fan are immediately turned off and the defrost heater 300 is turned on after the strong cooling and cold storage stage before defrosting is terminated. The conditions for shutting down the defrost heater 300 are: the evaporator temperature reaches the preset defrost exit temperature threshold, or the defrost duration reaches the preset maximum defrost time threshold.

[0061] It should be understood that the pre-defrost strong cooling and cold storage stage is the stage in which the inverter compressor 200 is kept running at a high frequency before the defrost heater 300 is started, and cold energy is prioritized to be delivered to the freezer compartment, allowing the freezer compartment to accumulate sufficient cold energy in advance. The conditions for terminating this stage are generally that the temperature of the freezer compartment drops to the preset cold storage end temperature, or the cold storage operation time reaches the preset maximum cold storage time. If either condition is met, the pre-defrost strong cooling and cold storage stage will end, and the subsequent defrosting process will begin.

[0062] Setting two conditions for exiting defrosting is to balance the reliability of defrosting and the efficiency of temperature control: If the amount of frost on the evaporator is small and defrosting can be completed in a short time, then when the evaporator temperature rises to the preset defrost exit temperature threshold, it means that the frost has completely melted. At this time, the defrost heater 300 can be turned off directly to end defrosting and avoid unnecessary heat input; If the amount of frost on the evaporator is large and the defrost exit temperature threshold is not reached for a long time, the defrost heater 300 will also be turned off when the defrosting duration reaches the preset maximum defrosting time threshold to avoid the accumulation of too much excess heat in the cabinet and affecting the subsequent room temperature control.

[0063] Specifically, the preset defrosting exit temperature threshold is 3℃~8℃, preferably 8℃; the preset maximum defrosting time threshold is 30 minutes~60 minutes.

[0064] In some embodiments, the preset defrosting trigger conditions include: the cumulative running time of the variable frequency compressor 200 reaches a preset cycle threshold, or the evaporator temperature is lower than a preset frosting temperature threshold.

[0065] It should be understood that the cumulative operation of the inverter compressor 200 reaching the preset cycle threshold is a general triggering condition based on the common frosting pattern of air-cooled refrigerators: during the refrigeration process, the evaporator continuously accumulates frost. After a certain cumulative operating time, the amount of frost will significantly affect the refrigeration efficiency, thus triggering the defrosting process. The preset cycle threshold is 8 to 16 hours. The evaporator temperature falling below the preset frosting temperature threshold is a personalized triggering condition based on the actual heat exchange state of the evaporator: as the amount of frost on the evaporator increases, the frost layer hinders heat exchange, causing the evaporator temperature to drop continuously. When the temperature drops to the corresponding threshold, it indicates that the frost has reached a point requiring treatment. At this time, even if the cumulative operating time of the inverter compressor 200 has not yet reached the cycle threshold, defrosting will be triggered to ensure that the refrigeration efficiency is not affected. The preset frosting temperature threshold is -27℃ to -32℃. The combination of these two triggering conditions can accommodate the defrosting needs under different usage scenarios, avoiding unnecessary defrosting operations while ensuring that frost issues that already require treatment are not overlooked.

[0066] See Figures 6-7 This application also provides an intelligent cooling supplementation control system for a frost-free refrigerator before defrosting, including: a freezer temperature sensor 121, a refrigerator temperature sensor 111, an evaporator temperature sensor, a variable frequency compressor 200, a defrost heater 300, a refrigeration fan 220, a main control microcontroller unit, and a refrigerator damper actuator or solenoid valve 203 for controlling the on / off of refrigeration in the refrigerator compartment. The main control microcontroller unit is electrically connected to the freezer temperature sensor 121, the refrigerator temperature sensor 111, the evaporator temperature sensor, the variable frequency compressor 200, the defrost heater 300, the refrigerator damper actuator or solenoid valve 203, and the refrigeration fan 220, respectively. The main control microcontroller unit is configured to execute the intelligent cooling supplement control method for the air-cooled refrigerator before defrosting provided in the above embodiments.

[0067] It should be understood that the freezer compartment temperature sensor 121 is used to collect the internal temperature of the freezer compartment in real time and transmit the temperature signal to the main control microcontroller unit; the refrigerator compartment temperature sensor 111 is responsible for collecting the internal temperature signal of the refrigerator compartment and also transmitting it to the main control microcontroller unit; the evaporator temperature sensor is used to detect the current temperature of the evaporator in real time, providing data support for judging the frosting status; the inverter compressor 200 is used to provide the power required for refrigeration and can adjust the operating power and speed according to control commands; the defrost heater 300 is responsible for starting after defrosting is triggered to heat and defrost the evaporator; the refrigeration fan 220 is used to deliver cooling air to the freezer compartment to realize the circulation and distribution of cold energy in the compartment; the refrigerator damper actuator or solenoid valve 203 controls the supply of cold energy to the refrigerator compartment by opening or closing, thereby regulating the refrigerator compartment temperature. The main control microcontroller unit receives the signals collected by all temperature sensors, judges according to the preset control logic, outputs the corresponding control commands, drives each component to perform corresponding actions, and finally completes the intelligent supplemental cooling control process before defrosting.

[0068] In some embodiments, see Figures 2-3 The air-cooled refrigerator with a refrigeration damper provided in this embodiment is divided into a first compartment 110 (upper part) and a second compartment 120 (lower part) by a partition. The first compartment 110 can be set as a refrigerator compartment (1~10℃) according to the user's needs; the second compartment 120 can be set as a freezer compartment (-16~-24℃) according to the user's needs. The freezer compartment is equipped with a second evaporator 207, a refrigeration fan 220 and a defrost heater 300; the defrost heater 300 is installed below the evaporator for defrosting.

[0069] The cooling capacity generated by the second evaporator 207 can be circulated to the refrigerator compartment through the refrigeration fan 220 to achieve cooling of both the refrigerator and freezer compartments. The temperature of the refrigerator compartment is controlled by the refrigeration damper 130. When the refrigerator compartment reaches the shutdown threshold, the refrigeration damper 130 is closed; conversely, when the refrigerator compartment reaches the start-up threshold, the refrigeration damper 130 is opened and the variable frequency compressor 200 and the refrigeration fan 220 are started.

[0070] Its refrigeration system, such as Figure 3 As shown, this is a single-cycle system. It includes a variable frequency compressor 200, a condenser 201, a dryer filter 202, a second capillary tube 206, and a second evaporator 207 (located in the rear air duct of the freezer compartment).

[0071] In this single-cycle refrigeration system structure, when the variable frequency compressor 200 is running, the refrigeration fan 220 runs synchronously, and the refrigeration damper 130 is opened according to the refrigeration demand of the refrigeration compartment.

[0072] In other embodiments, see Figures 4-5The air-cooled refrigerator with an electromagnetic valve provided in this embodiment includes a cabinet, which is divided into a first compartment 110 (upper part) and a second compartment 120 (lower part) by a partition. The first compartment 110 can be set as a refrigerator compartment (1~10℃) according to the user's needs; the second compartment 120 can be set as a freezer compartment (-16~-24℃) according to the user's needs. The freezer compartment is equipped with a second evaporator 207, a refrigeration fan 220, and a defrost heater 300; the defrost heater 300 is installed below the evaporator for defrosting. The refrigerator compartment is equipped with a first evaporator 205 and a refrigeration fan 210 to form the refrigerator compartment refrigeration system.

[0073] like Figure 5 As shown, the dual-cycle refrigeration system includes an inverter compressor 200, a condenser 201, a dryer filter 202, and a solenoid valve 203. The inlet of the solenoid valve 203 is connected to the outlet of the dryer filter 202. The first outlet of the solenoid valve 203 is connected to a first capillary tube 204, which is connected to a first evaporator 205 (located in the rear air duct of the first compartment 110). The second outlet of the solenoid valve 203 is connected to a second capillary tube 206, which is connected to a second evaporator 207 (located in the rear air duct of the second compartment 120). The outlet of the first evaporator 205 is connected to the inlet of the second evaporator 207. The outlet of the second evaporator 207 is connected to the return air port of the inverter compressor 200 via a refrigerator return air pipe.

[0074] In this dual-cycle refrigeration system structure, when the solenoid valve 203 opens only the first outlet, the refrigerant flows through the first capillary tube 204, the first evaporator 205, and the second evaporator 207, and then directly returns to the inverter compressor 200; when the solenoid valve 203 opens only the second outlet, the refrigerant flows through the second capillary tube 206 and the second evaporator 207 before returning to the inverter compressor 200; when both outlets are opened simultaneously, a series-parallel mixed flow path is formed to achieve maximum cooling capacity.

[0075] Regarding the air duct system, a refrigeration fan 210 is installed at the first evaporator 205 to blow cold air into the first compartment 110; a refrigeration fan 220 is installed at the second evaporator 207 to blow cold air into the second compartment 120.

[0076] The refrigerant flow direction is changed by solenoid valve 203, so as to achieve synchronous cooling of the refrigerator and freezer compartments or cooling of the freezer compartment alone.

[0077] The temperature detection unit of the two types of refrigerators mentioned above includes a refrigerator compartment temperature sensor 111 installed in the first compartment 110 and a freezer compartment temperature sensor 121 installed in the second compartment 120, as well as a sensor installed on the second evaporator 207, for monitoring whether the temperature rise during defrosting reaches the defrost heater 300 stop working temperature threshold.

[0078] The refrigerator's main control microcontroller receives sensor signals and user commands, and controls the operation of components such as the inverter compressor 200, the refrigerator damper 130 or solenoid valve 203, the freezer fan 220 or the refrigerator fan 210, and the defrost heater 300.

[0079] In some embodiments, the main control microcontroller unit further includes a timing module for recording the duration of the pre-defrost strong cooling and cold storage phase and comparing it with a preset maximum strong cooling time threshold.

[0080] Specifically, once the pre-defrost intelligent cooling replenishment process is initiated, the timing module starts timing simultaneously. As the strong cooling and cold storage process progresses, if the freezer temperature has not yet dropped to the preset target cooling replenishment temperature, and the duration recorded by the timing module has reached the preset maximum strong cooling time threshold, the main control microcontroller unit will directly trigger the exit from the pre-defrost strong cooling and cold storage stage and enter the subsequent defrosting preparation process. This avoids excessive energy consumption due to prolonged strong cooling while ensuring that the defrosting process can start on time. If the freezer temperature has already dropped to the preset target cooling replenishment temperature before the timing reaches the maximum strong cooling time threshold, the main control microcontroller unit will also directly terminate the strong cooling and cold storage stage, and the timing module will stop timing simultaneously, waiting to enter the defrosting process.

[0081] In some embodiments, the main control microcontroller unit further includes a feedforward control module for calculating and outputting the target frequency of the inverter compressor 200 in real time based on the deviation between the freezer temperature and the target value and the expected defrosting end time.

[0082] Specifically, during the pre-defrost cooling and cold storage phase, the feedforward control module collects the actual temperature of the freezer compartment in real time, calculates the difference between this temperature and the preset target cooling temperature, and estimates the remaining time before the defrost process is expected to begin, based on the system's preset defrost start time and the duration of the cooling operation. Based on these two parameters, the module directly outputs the target operating frequency of the inverter compressor 200, adapted to the current operating conditions. This avoids the accumulation of temperature deviations that could lead to subsequent temperature adjustment lag, allowing the freezer compartment temperature to drop more smoothly and efficiently to the target range. This ensures that the cold storage effect meets the temperature requirements of the defrost process while avoiding unnecessary energy consumption from the high-frequency operation of the inverter compressor 200, thus optimizing temperature control accuracy and energy efficiency.

[0083] Actual test results of the intelligent cooling control method before defrosting are shown in the figure below. Figure 8 As shown, before the refrigerator reaches the defrosting condition, the temperature of the refrigerator and freezer compartments does not remain stable, and there is no strong cooling and cold storage action before defrosting. After defrosting, the temperature of the freezer and refrigerator compartments rises significantly, which is not conducive to food preservation.

[0084] Actual test results of the intelligent cooling supplementation control method for the air-cooled refrigerator before defrosting according to this invention are shown in the figure below. Figure 9As shown, after the defrosting conditions are met, the present invention first executes a strong cooling and cold storage phase: the target temperature of the refrigerator compartment is lowered by 0.5°C, the stop point of the freezer compartment is lowered by 4°C to -23°C, and the variable frequency compressor 200 runs at high frequency until the freezer compartment temperature is reached or the strong cooling time reaches 180 minutes, at which point the defrosting phase begins; after defrosting, the variable frequency compressor 200 starts at high frequency to prioritize cooling the freezer compartment. During the supplemental cooling period, the main control microcontroller unit and the speed of the variable frequency compressor 200 are combined to achieve a balance between rapid temperature increase and energy saving and noise reduction. Through the above control, it is ensured that the maximum average temperature of the freezer compartment after defrosting is ≤-12°C.

[0085] In summary, the beneficial effects of this invention compared with related technologies are shown in the table below:

[0086] As can be seen from the above technical solutions, the embodiments of this application provide an intelligent cooling control method and system for air-cooled refrigerators before defrosting. The method is executed after the preset defrosting trigger conditions are met and before the defrosting heater is actually started. It includes a pre-defrosting strong cooling and cold storage stage, which includes: controlling the refrigerator compartment to maintain a cooling state and shifting the target control temperature of the refrigerator compartment downward by a first offset; shifting the stop temperature threshold of the freezer compartment downward by a second offset, wherein the second offset is greater than the first offset; controlling the inverter compressor to run continuously at a first frequency higher than the conventional cooling frequency; when the actual temperature of the freezer compartment reaches the downwardly shifted stop temperature threshold, or when the duration of the pre-defrosting strong cooling and cold storage stage reaches the preset maximum strong cooling time threshold, terminating the pre-defrosting strong cooling and cold storage stage and starting the defrosting heater, so as to solve the problem of the significant rise in the compartment temperature during defrosting affecting the preservation of food.

[0087] Similar parts between the embodiments provided in this application can be referred to mutually. The specific implementation methods provided above are only a few examples under the overall concept of this application and do not constitute a limitation on the scope of protection of this application. For those skilled in the art, any other implementation methods extended from the solution of this application without creative effort shall fall within the scope of protection of this application.

Claims

1. An intelligent cold supplement control method before defrosting of an air-cooled refrigerator, characterized by, The method is executed after the preset defrost triggering conditions are met and before the defrost heater is actually started, including a pre-defrost strong cooling and cold storage stage, which includes: Control the refrigerator compartment to maintain a cooling state, and shift the target control temperature of the refrigerator compartment downward by a first offset amount; The shutdown temperature threshold of the freezer compartment is shifted downward by a second offset, wherein the second offset is greater than the first offset; The variable frequency compressor is controlled to operate continuously at a first frequency higher than the conventional refrigeration frequency; When the actual temperature of the freezer reaches the shutdown temperature threshold after downward shift, or when the duration of the pre-defrost strong cooling and cold storage stage reaches the preset maximum strong cooling time threshold, the pre-defrost strong cooling and cold storage stage is terminated and the defrost heater is started.

2. The method of claim 1, wherein the method is characterized by, The first offset ranges from 0.3℃ to 1.5℃, and the second offset ranges from 2℃ to 6℃.

3. The method of claim 1, wherein the method comprises: The normal shutdown temperature threshold range for the freezer compartment is -19℃ to -21℃, and the downward shifted shutdown temperature threshold ranges from -23℃ to -25℃.

4. The method of claim 1, wherein the method is characterized by, The first frequency ranges from 70 Hz to 120 Hz, and the conventional cooling frequency ranges from 50 Hz to 80 Hz.

5. The method of claim 1, wherein the method is characterized by, The preset maximum cooling time threshold ranges from 120 minutes to 240 minutes.

6. The method of claim 1, wherein the method is characterized by, During the pre-defrost strong cooling and cold storage phase, the operation of lowering the target control temperature of the refrigerator compartment and the operation of lowering the shutdown temperature threshold of the freezer compartment are executed simultaneously.

7. The method of claim 1, wherein the method is characterized by, The method further includes a recovery control phase after the defrosting heater finishes defrosting, the recovery control phase including: The variable frequency compressor is controlled to start at a second frequency higher than the conventional refrigeration frequency; Prioritize cooling the freezer compartment. Once the freezer compartment temperature returns to below the normal freezing setting temperature, restore normal cooling to the refrigerator compartment.

8. The method of claim 1, wherein the method is characterized by, The defrost heater is activated when the compressor and fan are immediately turned off and the defrost heater is turned on after the pre-defrost cooling and cold storage phase has ended. The conditions for shutting down the defrosting heater are: the evaporator temperature reaches the preset defrost exit temperature threshold, or the defrosting duration reaches the preset maximum defrost time threshold.

9. The method of claim 1, wherein the method is characterized by, The preset defrosting trigger conditions include: the compressor's cumulative running time reaches a preset cycle threshold, or the evaporator temperature is lower than a preset frosting temperature threshold.

10. An intelligent cold supplement control system before defrosting of an air-cooled refrigerator, characterized by, include: Freezer temperature sensor, refrigerator temperature sensor, evaporator temperature sensor, variable frequency compressor, defrost heater, refrigeration fan, main control microcontroller unit, and refrigerator damper actuator or solenoid valve for controlling the refrigeration on / off of the refrigerator compartment; The main control microcontroller unit is electrically connected to the freezer temperature sensor, the refrigerator temperature sensor, the evaporator temperature sensor, the variable frequency compressor, the defrost heater, the refrigerator damper actuator or solenoid valve, and the refrigeration fan, respectively. The main control microcontroller unit is configured to execute the intelligent supplemental cooling control method for the air-cooled refrigerator before defrosting, as described in any one of claims 1 to 9.

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