Defrosting control method and device based on difference extraction

Abstract

The embodiment of the present application relates to a defrosting control method and device based on difference extraction, the method comprising: extracting difference data in a first time period when a first flag bit issued by a refrigerator terminal is received; extracting valid difference data from the difference data in the first time period; calculating a standard value; judging whether the running condition of the refrigerator terminal in the first time period hits an abnormal judgment rule in a performance auxiliary judgment rule; if any abnormal judgment rule is not hit, issuing a first delayed defrosting instruction of the current defrosting cycle to the refrigerator terminal, so that the refrigerator terminal determines a second predetermined defrosting time; and defrosting is performed at the second predetermined defrosting time under the condition that no second delayed defrosting instruction is received before the second predetermined defrosting time; if at least one abnormal judgment rule is hit, the refrigerator terminal is informed to defrost at a first predetermined defrosting time. The present application can delay defrosting under the condition that the running state of the refrigerator terminal is stable.

Description

Technical Field

[0001] This invention relates to the field of refrigerator technology, and in particular to a defrosting control method and apparatus based on difference extraction. Background Technology

[0002] Frosting on the condenser is a major pain point for refrigerator products.

[0003] Because condenser frost buildup can cause malfunctions in refrigerator cooling, ultimately affecting its preservation performance, the industry has been exploring ways to precisely control condenser frost buildup and reduce cooling anomalies caused by it. To minimize the impact of condenser frost, refrigerator manufacturers have developed a defrosting algorithm based on years of experimental experience, which calculates the cumulative defrosting interval based on compressor operating time, operating rate, and door opening time. The core of this algorithm is to prioritize preventing condenser frost buildup even if it requires a higher defrosting frequency. For example, a certain brand of refrigerator may require defrosting approximately once every 24 hours.

[0004] However, a higher defrosting frequency increases the refrigerator's power consumption, and the freezer temperature rises when the defrosting heater is working, creating temperature shocks that affect the preservation of food stored in the freezer. Furthermore, after defrosting, the high freezer temperature causes the compressor to operate at high speed for intensive cooling, but this reduces the compressor's lifespan and generates significant noise. Summary of the Invention

[0005] To solve the above-mentioned technical problems, or at least partially solve them, the present invention provides a defrosting control method and apparatus based on difference extraction.

[0006] According to a first aspect, the defrosting control method based on difference extraction provided in the embodiments of the present invention, wherein the method is executed by a data platform, the method comprising:

[0007] Upon receiving the first flag bit sent by the refrigerator terminal, the difference data within a first time period is extracted. The first time period is from the end of the previous defrost cycle to the moment the refrigerator terminal sends the first flag bit. The difference data is the difference between the freezer compartment temperature and the evaporator compartment temperature of the refrigerator terminal. The refrigerator terminal sends the first flag bit to the data platform via the IoT platform at a preset time point before reaching the first predetermined defrost time. The first predetermined defrost time is obtained by adding a defrost reference interval time to the end of the previous defrost cycle. The defrost reference interval time is a reference value for the defrost interval time calculated by the refrigerator terminal based on its operating status.

[0008] According to the difference extraction rules, valid difference data is extracted from the difference data within the first time period; the average value of the valid difference data within the first time period is calculated; the average fluctuation value of the valid difference data within the first time period is calculated based on the average value; the average value and the average fluctuation value are summed to obtain a standard value, and the standard value is stored; the standard value is used as the basis for determining whether further delayed defrosting is needed.

[0009] Based on the valid difference data within the first time period, determine whether the operation of the refrigerator terminal within the first time period matches the abnormal judgment rule in the performance auxiliary judgment rule.

[0010] If any of the anomaly judgment rules are not met, the IoT platform sends the first delayed defrost command for this defrost cycle to the refrigerator terminal, so that the refrigerator terminal determines the second predetermined defrost time, and performs defrosting at the second predetermined defrost time if no further delayed defrost command is received before the second predetermined defrost time; after sending the first delayed defrost command, it is also determined whether a second delayed defrost command needs to be sent according to the standard value; wherein, the second predetermined defrost time is the first predetermined defrost time plus a delay period;

[0011] If at least one of the anomaly detection rules is met, the refrigerator terminal is notified through the IoT platform to defrost at the first predetermined defrosting time.

[0012] According to a second aspect, the defrosting control device based on difference extraction provided in the embodiments of the present invention, the device being deployed on a data platform, the device comprising:

[0013] The first extraction module is used to extract difference data within a first time period when it receives a first flag bit sent by the refrigerator terminal; wherein, the first time period is from the end of the last defrost to the time when the refrigerator terminal sends the first flag bit, the difference data is the difference between the freezer temperature and the evaporator temperature of the refrigerator terminal, the refrigerator terminal sends the first flag bit to the data platform through the Internet of Things platform at a preset time point before reaching the first predetermined defrost time, the first predetermined defrost time is obtained by adding a defrost reference interval time to the end of the last defrost; the defrost reference interval time is a reference value of the defrost interval time calculated by the refrigerator terminal based on the operating status of the refrigerator terminal;

[0014] The second extraction module is used to extract valid difference data from the difference data within the first time period according to the difference extraction rules; calculate the average value of the valid difference data within the first time period; calculate the average fluctuation value of the valid difference data within the first time period based on the average value; sum the average value and the average fluctuation value to obtain a standard value, and store the standard value; the standard value is used as the basis for determining whether further delayed defrosting is needed.

[0015] The first judgment module is used to determine whether the operation of the refrigerator terminal in the first time period hits the abnormal judgment rule in the performance auxiliary judgment rule based on the effective difference data in the first time period.

[0016] The first sending module is used to send the first delayed defrost instruction of the current defrost cycle to the refrigerator terminal through the IoT platform if any abnormal judgment rule is not hit, so that the refrigerator terminal can determine the second predetermined defrost time, and perform defrosting at the second predetermined defrost time if no further delayed defrost instruction is received before the second predetermined defrost time; after sending the first delayed defrost instruction, it also determines whether it is necessary to send a second delayed defrost instruction according to the standard value; wherein, the second predetermined defrost time is the first predetermined defrost time plus a delay time;

[0017] The second sending module is used to notify the refrigerator terminal to defrost at the first predetermined defrosting time if at least one of the anomaly judgment rules is met.

[0018] The defrosting control method and apparatus based on difference extraction provided in this invention involve the refrigerator terminal sending a first flag bit to a data platform at a preset time point before reaching a first predetermined defrosting time. When the data platform receives the first flag bit, it extracts the difference data within a first time period, extracts the valid difference data, and calculates a standard value. It then determines whether the refrigerator terminal's operation within the first time period matches any of the abnormal judgment rules in the performance auxiliary judgment rules. If no abnormal judgment rule is matched, the system sends the first delayed defrosting instruction for this defrosting cycle to the refrigerator terminal, enabling the refrigerator terminal to determine a second predetermined defrosting time. If no further delayed defrosting instruction is received before the second predetermined defrosting time, defrosting is performed at the second predetermined defrosting time. The system also determines whether further delayed defrosting is needed based on the standard value. If at least one abnormal judgment rule is matched, the system notifies the refrigerator terminal via the Internet of Things platform to perform defrosting at the first predetermined defrosting time. Therefore, the method provided in this invention delays defrosting when the refrigerator terminal's operation is stable and does not delay defrosting when the operation is unstable. This reduces the number of defrosting cycles and lowers the refrigerator terminal's energy consumption when the operation is stable. By reducing the frequency of defrosting, temperature shocks caused by the defrosting heater are minimized, preventing any impact on food preservation. Furthermore, it reduces the impact on compressor lifespan caused by the need for high-speed compressor operation for intensive cooling after defrosting, thus extending compressor lifespan and reducing noise. Attached Figure Description

[0019] The accompanying drawings, which are incorporated in and form part of this specification, illustrate embodiments consistent with the invention and, together with the description, serve to explain the principles of the invention.

[0020] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, for those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0021] Figure 1 This is a flowchart illustrating a defrosting control method based on difference extraction in one embodiment of the present invention. Detailed Implementation

[0022] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0023] In a first aspect, embodiments of the present invention provide a defrosting control method based on difference extraction. The method is executed by a data platform, which involves a refrigerator terminal, an Internet of Things (IoT) platform, and a data platform. The refrigerator terminal and the data platform interact with each other through the IoT platform.

[0024] See Figure 1 The method includes the following steps S110 to S150:

[0025] S110. Upon receiving the first flag bit sent by the refrigerator terminal, extract the difference data within a first time period; wherein, the first time period is from the end of the last defrost to the moment when the refrigerator terminal sends the first flag bit, the difference data is the difference between the freezer temperature and the evaporator temperature of the refrigerator terminal, the refrigerator terminal sends the first flag bit to the data platform through the Internet of Things platform at a preset time point before reaching the first predetermined defrost moment, the first predetermined defrost moment is obtained by adding a defrost reference interval time to the end of the last defrost; the defrost reference interval time is a reference value of the defrost interval time calculated by the refrigerator terminal based on the operating status of the refrigerator terminal;

[0026] The defrost baseline interval can be calculated using the refrigerator's defrost algorithm. This algorithm calculates a baseline value for the defrost interval based on operational data such as compressor operating time, operating rate, and door opening time. Therefore, the defrost baseline interval changes with the refrigerator's operating conditions, rather than remaining constant. For example, a calculated defrost baseline interval might be 8 hours.

[0027] The refrigerator terminal sends a first flag bit at a preset time point before the first predetermined defrost time. The first predetermined defrost time is obtained by adding the defrost baseline interval time to the end time of the previous defrost operation. For example, if the last defrost operation ended at 1:00 AM on a certain day, and the defrost baseline interval time is 8 hours, then the first predetermined defrost time is 9:00 AM on that day. In other words, the refrigerator terminal initially anticipates defrosting at 9:00 AM, and therefore sends the first flag bit 0xFF to the data platform at 8:30 AM. That is, the first flag bit 0xFF is sent to the data platform half an hour before the first predetermined defrost time to determine whether defrosting needs to be delayed. If delayed defrosting is needed, the defrosting will proceed after a certain time from 9:00 AM; if delayed defrosting is not needed, defrosting will begin at 9:00 AM.

[0028] The first time period is from the end of the last defrost cycle to the time when the refrigerator terminal sends the first flag bit. The end of the last defrost cycle was 1:00 AM on a certain day. The refrigerator terminal sent the first flag bit 0xFF to the data platform at 8:30 AM. Therefore, the first time period is from 1:00 AM to 8:30 AM.

[0029] The difference data refers to the temperature difference between the freezer compartment and the evaporator compartment of the refrigerator terminal. Therefore, the difference data represents the difference between the two temperatures. Within the first time period, there are multiple time points. At each time point, the temperature sensors in the refrigerator terminal can collect the freezer compartment temperature and the evaporator compartment temperature. Therefore, the difference between the two temperatures is calculated to obtain a difference data point. The difference data points corresponding to each time point form a time series, thus obtaining the difference data for the first time period.

[0030] S120. According to the difference extraction rules, extract the effective difference data from the difference data in the first time period; calculate the average value of the effective difference data in the first time period; calculate the average fluctuation value of the effective difference data in the first time period based on the average value; sum the average value and the average fluctuation value to obtain a standard value, and store the standard value; the standard value is used as the basis for judging whether further delayed defrosting is needed.

[0031] In other words, after extracting the difference data for the first time period, because there may be invalid difference data, in order to avoid invalid difference data affecting subsequent steps, invalid difference data is extracted, and valid difference data is retained; or, valid difference data is extracted directly. Specifically, here, invalid difference data is removed or valid difference data is extracted according to the preset difference extraction rules.

[0032] In one embodiment, the difference extraction rule may include at least one of the following: using the difference data of the compressor of the refrigerator terminal during its operation after being turned on as valid difference data; using the difference data of the evaporator temperature of the refrigerator terminal being lower than a preset temperature as valid difference data; using the difference data of the second time period after the defrost heater of the refrigerator terminal finishes heating as invalid difference data; using the difference data of the third time period after the door opening event occurs as invalid difference data; using the difference data of the fourth time period after the refrigerator door changes from the open state to the closed state as invalid difference data; wherein, the door opening event includes any one of the door opening events corresponding to the refrigerator compartment, the freezer compartment, and the variable temperature compartment.

[0033] In the difference extraction rule, the difference data of the refrigerator terminal's compressor during the working period after it is turned on is taken as the valid difference data. That is to say, only the difference data generated during the compressor's working period is valid difference data, while the difference data generated in other time periods is invalid difference data.

[0034] In the difference extraction rule, the difference data where the evaporator temperature at the refrigerator terminal is lower than the preset temperature is taken as valid difference data. That is to say, when the evaporator temperature is lower than the preset temperature, it means that the refrigerator terminal has entered a stable period. Therefore, the difference data generated at this time is taken as valid difference data, and the difference data that has not entered the stable period is taken as invalid difference data.

[0035] In the difference extraction rule, the difference data in the second time period after the defrost heater of the refrigerator terminal finishes heating is regarded as invalid difference data. That is to say, in the initial time period after the defrost heater finishes working, the difference data is affected by the defrost heater and is biased. Therefore, the difference data in the second time period after the defrost heater finishes heating is regarded as invalid difference data, and the difference data after the second time period is regarded as valid difference data.

[0036] Specifically, in the difference extraction rules, the difference data within the third time period after the door opening event is considered invalid difference data. The door opening event includes any one of the door opening events corresponding to the refrigerator compartment, freezer compartment, and variable temperature compartment. In other words, all door opening events of the refrigerator terminal, especially single-system refrigerators, in the refrigerator compartment, freezer compartment, and variable temperature compartment are excluded, thus eliminating the influence of door opening events.

[0037] Specifically, the difference data during the fourth time period after the refrigeration damper changes from the open state to the closed state is considered invalid difference data. In other words, the difference data is unstable for a short period of time after the refrigeration damper changes from the open state to the closed state, so the difference data during this period is considered invalid difference data.

[0038] As can be seen, by using the difference extraction rules, the influence of some factors can be eliminated, thereby obtaining stable and effective difference data that can accurately reflect the difference between the temperature of the freezer compartment and the temperature of the evaporator compartment.

[0039] In one embodiment, it is necessary to predetermine the preset temperature, second time period, third time period, and fourth time period in the difference extraction rule. The specific determination process may include the following steps S1 to S7:

[0040] S1. Extract the evaporator temperature of the refrigerator terminal during the first time period, the difference data at different time points after the defrost heater finishes working, the difference data at different time points after the door opening event occurs, and the difference data at different time points after the refrigerator door switches from open to closed.

[0041] Specifically, the difference data corresponding to different time points under different conditions is extracted from the difference data within the first time period.

[0042] S2. Using the box method, outlier data are removed from the evaporator temperature of the refrigerator terminal during the first time period, the difference data at different time points after the defrost heater finishes working, the difference data at different time points after the door opening event occurs, and the difference data at different time points after the refrigerator door is switched from open to closed.

[0043] For example, for the time series of evaporator temperatures within the first time period, the series is arranged in ascending or descending order to obtain a sorted sequence. Then, the evaporator temperatures q1 at the 1 / 4 position and q3 at the 3 / 4 position are extracted from this sorted sequence. Then, iqr = q3 - q1 is calculated. Evaporator temperatures less than or equal to q1 - 1*iqr and greater than or equal to q3 + 1*iqr are then removed as outliers, resulting in a sequence with outliers eliminated. This process is the process of the box method.

[0044] S3. Based on the temperatures of each evaporator during the first time period, determine the first range of values ​​for the evaporator temperature when the evaporator is in a stable period.

[0045] That is, based on the evaporator temperatures after removing outliers in the first time period, the range of evaporator temperatures can be determined and denoted as the first range.

[0046] S4. Based on the difference data at different time points after the defrosting heater finishes working, determine the change of the difference data at different time points after the defrosting heater finishes working, and determine the second value range corresponding to the second time period based on the change of the difference data at different time points after the defrosting heater finishes working.

[0047] That is, after removing outliers from the difference data at different time points after the defrosting heater finishes working in the first time period, we can know the changes in the difference data at different time points after the defrosting heater finishes working. Then, based on these changes, we can determine the distribution of the difference data at each time point when it is in a stable state, and thus know the second value range corresponding to the second time period.

[0048] S5. Based on the difference data at different time points after the door opening event, determine the change of the difference data at different time points after the door opening event, and determine the third value range corresponding to the third time period based on the change of the difference data at different time points after the door opening event.

[0049] That is, for the difference data at different time points after the door opening event in the first time period, after removing outliers, we can know the changes in the difference data at each time point after the door opening time. Then, based on these changes, we can determine the distribution of the difference data at each time point when it is in a stable state, and thus know the third value range corresponding to the third time period.

[0050] S6. Based on the difference data corresponding to different time points after the refrigeration damper is switched from open to closed, determine the change of the difference data at different time points after the refrigeration damper is switched from open to closed, and determine the fourth value range corresponding to the fourth time period based on the change of the difference data at different time points after the refrigeration damper is switched from open to closed.

[0051] That is, after removing outliers, we can determine the changes in the difference data at different time points after the refrigeration damper is switched from open to closed. Based on these changes, we can determine the distribution of the difference data at each time point when the difference data is in a stable state, and thus determine the fourth value range corresponding to the fourth time period.

[0052] S7. Select the preset temperature from the first value range, select the second time period from the second value range, select the third time period from the third value range, and select the fourth time period from the fourth value range.

[0053] For example, if the first value range is (a1, a2), a temperature value is selected from this range through iteration. Then, keeping other parameters (i.e., the second, third, and fourth time periods) unchanged, the selected temperature value is substituted into the aforementioned difference extraction rule. It is then determined whether the difference data extracted according to the current difference extraction rule corresponds to the temperature at which the evaporator enters a stable period. In this way, an optimal temperature value can be selected from the first value range and used as the preset temperature. The selection of the second, third, and fourth time periods follows the same principle.

[0054] For example, in the difference extraction rules, the preset temperature is set to -20 degrees Celsius, the second time period is set to 1 hour, the second time period is set to 30 minutes, and the fourth time period is set to 10 minutes.

[0055] Furthermore, after extracting the valid difference data, a standard value is calculated, which is used as the basis for determining whether further defrosting is needed.

[0056] Specifically, the process of calculating the standard value is as follows: calculate the average value of the effective difference data within the first time period; calculate the average fluctuation value of the effective difference data within the first time period based on the average value; sum the average value and the average fluctuation value to obtain the standard value, and store the standard value; the standard value is used as the basis for determining whether further delayed defrosting is needed.

[0057] Specifically, the average value of the valid difference data within the first time period can be calculated using the following formula. This average value can be denoted as the first average value.

[0058]

[0059] Where Ac is the first average value, n is the number of valid difference data points within the first time period, and the valid difference data points within the first time period are x1, x2, x3, ... x n .

[0060] Specifically, the average fluctuation value can be calculated using a first formula, which is:

[0061]

[0062] Where Ab is the average fluctuation value, n is the number of valid difference data within the first time period, and x1, x2, x3, ... x n The valid difference data within the first time period are represented by Ac, where Ac is the first average value.

[0063] Then, Ac and Ab are summed to obtain the standard value A, which is then stored for direct use in subsequent judgments.

[0064] S130. Based on the valid difference data within the first time period, determine whether the operation of the refrigerator terminal within the first time period matches the abnormal judgment rule in the performance auxiliary judgment rule.

[0065] Among them, the performance auxiliary judgment rule is the judgment rule for determining whether the refrigerator is operating well. The performance auxiliary judgment rule includes at least one anomaly judgment rule.

[0066] Specifically, if, based on the valid difference data within the first time period, the refrigerator terminal's operation within that time period matches one or more anomaly judgment rules, it indicates that the refrigerator terminal's operation is not good, and therefore, delayed defrosting is not suitable. Conversely, if the refrigerator terminal's operation within the first time period does not match any of the anomaly judgment rules, it indicates that the refrigerator terminal's operation within that time period is good, and delayed defrosting is permissible.

[0067] In one embodiment, the performance auxiliary judgment rule may include a first anomaly judgment rule, which includes: the compressor start-up rate of the refrigerator terminal is greater than 90% during the first time period, and the compressor speed exceeds a preset speed for a period of more than 60%; wherein, if the difference data in the first time period matches the first anomaly judgment rule, it is determined that there is a peak on the change curve of the difference data of the refrigerator terminal in the first time period.

[0068] In other words, the first anomaly detection rule is used to determine whether there are any "jump points" on the curve of the difference data over time within the first time period. A "jump point" refers to a point on the curve that jumps around.

[0069] The preset speed is, for example, 3000 RPM.

[0070] The uptime rate refers to the percentage of time the compressor operates within the first time period.

[0071] For example, if the compressor's operating rate exceeds 60% and the time spent at 3000 RPM or higher exceeds 60% in the first time period, it indicates that there are gaps in the difference data in the first time period, and delayed defrosting is not suitable in this case.

[0072] In one embodiment, the performance-assisted judgment rule may include a second anomaly judgment rule, which includes at least one of the following:

[0073] The number of valid difference data within the first time period is less than a preset number;

[0074] The average fluctuation value of the effective difference data within the first time period is greater than the preset value.

[0075] The preset quantity is, for example, 5. Typically, the number of difference data points in a defrosting cycle is around 100. If the number of valid difference data points is less than 5, it indicates that the difference data is greatly affected by external factors, resulting in a large number of invalid difference data points.

[0076] The preset value is, for example, 1. If the average fluctuation value of the effective difference data is greater than 1 within a defrosting cycle or within the first time period, it indicates that the effective difference data has problems of dispersion, non-aggregation, and non-convergence.

[0077] It is evident that if the valid difference data within the first time period matches at least one of the above-mentioned second anomaly judgment rules, it indicates that the data is inaccurate, of poor quality, and does not meet the data quality requirements, which will have a significant impact on subsequent steps.

[0078] In one embodiment, the performance-assisted judgment rule may include a third anomaly judgment rule, which includes:

[0079] The current time is more than 8 hours away from the start time of the last defrost, the refrigeration time tn is greater than or equal to tmax×1.8, and there is no refrigerator door opening event during the current refrigeration cycle;

[0080] Wherein, the refrigeration time tn is calculated from the moment the compressor is turned on for the second time in the first refrigeration cycle after the end of the previous defrosting, until the end of the nth refrigeration cycle in which the current moment is located; tmax is max(t2, t3); t2 is calculated from the end of two consecutive refrigeration cycles starting from the second refrigeration cycle; t3 is calculated from the end of two consecutive refrigeration cycles starting from the end of the third refrigeration cycle; the refrigeration cycle is calculated from the end of one refrigeration cycle until the end of the next refrigeration cycle.

[0081] The third anomaly judgment rule is used to determine whether there is a frost blockage problem at the refrigerator terminal.

[0082] The refrigeration cycle is the period from the end of one refrigeration cycle to the end of the next refrigeration cycle.

[0083] The refrigeration time tn is calculated from the moment the compressor is turned on for the second time in the first refrigeration cycle after the last defrost, until the end of the nth refrigeration cycle in which the current moment is located; where the current moment refers to the moment when the refrigerator terminal sends the first flag bit, and the nth refrigeration cycle in which the current moment is located is the current refrigeration cycle.

[0084] Where tmax is max(t2, t3), tmax refers to the steady-state refrigeration time of the refrigerator.

[0085] If the refrigerator terminal's operation matches the third abnormal judgment rule mentioned above, it indicates that the refrigerator terminal has experienced frost blockage, and in this case, defrosting will not be delayed.

[0086] As can be seen, the above performance-assisted judgment rules specify several specific situations in which delayed defrosting cannot be performed. Of course, there may also be other situations in which delayed defrosting is not suitable.

[0087] S140. If any of the abnormal judgment rules are not met, the first delayed defrosting instruction for this defrosting cycle is sent to the refrigerator terminal through the IoT platform, so that the refrigerator terminal determines the second predetermined defrosting time, and performs defrosting at the second predetermined defrosting time if no further delayed defrosting instruction is received before the second predetermined defrosting time; after sending the first delayed defrosting instruction, it is also determined whether a further delayed defrosting instruction needs to be sent according to the standard value; wherein, the second predetermined defrosting time is the first predetermined defrosting time plus a delay period;

[0088] In other words, if the refrigerator terminal does not trigger any of the anomaly detection rules, it indicates that the refrigerator terminal is operating stably and defrosting can be delayed. Therefore, the data platform issues an initial delayed defrosting command through the IoT platform, which is the first instruction to delay defrosting. After receiving the initial delayed defrosting command, the refrigerator terminal determines a second scheduled defrosting time. The second scheduled defrosting time is based on the first scheduled defrosting time with an added delay period. For example, if the delay period is 2 hours and the first scheduled defrosting time is 9:00 AM, then the second scheduled defrosting time is 11:00 AM.

[0089] Of course, defrosting will not necessarily occur at the second scheduled defrost time. Therefore, before the second scheduled defrost time arrives, the data platform may send another defrost delay command to the refrigerator terminal. In this case, the refrigerator terminal will update the second scheduled defrost time, for example, delaying it by two hours, so the updated second scheduled defrost time is 13:00. Moreover, the data platform may send multiple defrost delay commands to the refrigerator terminal, thus creating multiple delays.

[0090] It is evident that if the refrigerator terminal does not receive a further delay defrosting instruction from the data platform before the second predetermined defrosting time, the refrigerator terminal will perform defrosting when the second predetermined defrosting time is reached.

[0091] Understandably, after the data platform sends the initial defrost delay command to the refrigerator terminal, it will at some point determine whether defrost needs to be delayed again based on standard values. If so, it will send another defrost delay command to the refrigerator terminal; otherwise, it will not send another defrost delay command.

[0092] Furthermore, the method provided in this embodiment of the invention may further include the following steps S160 to S200:

[0093] S160. Upon receiving the second flag bit sent by the refrigerator terminal, obtain the difference data within the fifth time period and extract the valid difference data within the fifth time period; wherein, the fifth time period is from the time when the refrigerator terminal sends the first flag bit to the time when the refrigerator terminal sends the second flag bit; the refrigerator terminal sends the second flag bit to the data platform through the Internet of Things platform at a preset time point before the current second predetermined defrosting time.

[0094] Specifically, the refrigerator terminal will send the second flag bit to the data platform through the IoT platform at a preset time point before the current second predetermined defrost time. For example, if the current second predetermined defrost time is 11:00, the refrigerator terminal will send the second flag bit 0xFE to the data platform at 10:30, that is, send the second flag bit 0xFE 30 minutes in advance.

[0095] The fifth time period is from the time when the refrigerator terminal sends the first flag bit to the time when the refrigerator terminal sends the second flag bit. For example, if the refrigerator sends the first flag bit 0xFF to the data platform at 8:30 and the second flag bit 0xFE to the data platform at 10:30, then the fifth time period is from 8:30 to 10:30.

[0096] For example, after the data platform receives the second flag, it will extract the difference data from the time period from 8:30 to 10:30, extract the valid values ​​from the difference data in the fifth time period, obtain the valid difference data in the fifth time period, and then use the valid difference data for subsequent steps.

[0097] S170. Calculate the average value of the valid difference data within the fifth time period, and record this average value as the second average value;

[0098] For example, the valid difference data within the fifth time period are y1, y2, y3, ... y n The second average value is calculated using the following formula:

[0099]

[0100] Among them, Bc is the second average value.

[0101] S180. Determine whether the second average value is less than the standard value;

[0102] That is, determine whether the second average value Bc is less than the standard value A, where the standard value A is Ac+Ab.

[0103] S190. If so, the IoT platform sends a further delay defrosting instruction to the refrigerator terminal for the current defrosting cycle, so that the refrigerator terminal determines the second scheduled defrosting time after the current update, and performs defrosting at the second scheduled defrosting time after the current update if no further delay defrosting instruction is received before the second scheduled defrosting time after the current update. The second scheduled defrosting time after the current update is obtained by adding a delay time to the second scheduled defrosting time before the current update.

[0104] In other words, if the second average value is less than the standard value, it means that the operation of the refrigerator terminal fluctuates less and is relatively stable during the fifth time period, so defrosting can be delayed again.

[0105] If the second average value is lower than the standard value, the data platform will issue a further delay command for defrosting via the IoT platform. Upon receiving this command, the refrigerator terminal will update the second scheduled defrosting time. Specifically, the delay time will be increased from the previous scheduled defrosting time. For example, if the previous scheduled defrosting time was 11:00, adding a two-hour delay will result in an updated scheduled defrosting time of 13:00. If the refrigerator terminal does not receive a new delay command before 13:00, defrosting will begin at 13:00. Therefore, the refrigerator terminal has already delayed the defrosting time twice since 9:00.

[0106] Understandably, at 12:30, the refrigerator terminal will send the second flag bit to the data platform. At this time, the data platform will extract the difference data within the new fifth time period (i.e., 10:30 to 12:30), and then calculate the second average value within this fifth time period to determine whether the second average value is less than the aforementioned standard value. If it is less, the data platform will send another defrosting instruction to the refrigerator terminal, thus updating the second scheduled defrosting time to 15:00.

[0107] As can be seen, multiple delayed defrosting cycles are possible.

[0108] S200. Otherwise, the refrigerator terminal is notified through the IoT platform to defrost at the second predetermined defrosting time before this update.

[0109] That is, if the second average value is greater than or equal to the standard value, it means that the operation of the refrigerator terminal fluctuates greatly and is not very stable during the fifth time period, so no further delay is made.

[0110] For example, if the previous second scheduled defrost time was 11:00, and the second average value is greater than or equal to the standard value, the refrigerator terminal will perform defrosting at 11:00.

[0111] As can be seen, the above steps S160 to S200 can determine whether delayed defrosting is needed again.

[0112] S150. If at least one of the abnormal judgment rules is met, the refrigerator terminal is notified through the Internet of Things platform to defrost at the first predetermined defrosting time.

[0113] In other words, if the refrigerator terminal hits at least one of the abnormal judgment rules, it means that the refrigerator terminal is not operating stably. Therefore, the defrosting will not be delayed and the refrigerator terminal will defrost at the first predetermined defrosting time.

[0114] The data transmission between the refrigerator terminal, the IoT platform, and the data platform is a transparent transmission method.

[0115] In one embodiment, after receiving the instruction to delay defrosting again and determining the second predetermined defrosting time after this update, the refrigerator terminal is further configured to: calculate the current cumulative delay time within the current defrosting cycle, and determine whether the current cumulative delay time is less than the maximum delay time; if so, defrosting is performed at the second predetermined defrosting time after this update if no instruction to delay defrosting again is received before the second predetermined defrosting time after this update; otherwise, defrosting is performed at the second predetermined defrosting time before this update.

[0116] To avoid indefinite defrosting delays, a maximum delay time is set here. After the refrigerator terminal determines the second scheduled defrosting time after this update, the current cumulative delay time is accumulated from the initial delay. Then, it is checked whether the current cumulative delay time is less than the maximum delay time. If it is less, defrosting will proceed at the second scheduled defrosting time after this update, provided no further delay instruction is received before the second scheduled defrosting time after this update; that is, the second scheduled defrosting time after this update is valid. However, if it is greater than or equal to the maximum delay time, the second scheduled defrosting time after this update is invalid, and defrosting will proceed at the second scheduled defrosting time before this update.

[0117] In one embodiment, the refrigerator terminal is further configured to: time the current defrost interval within the current defrost cycle, and determine whether the current defrost interval is greater than or equal to the maximum defrost interval; if so, automatically enter the defrost state.

[0118] A maximum defrosting interval is set here. The current defrosting interval is the time from the end of the last defrosting to the current time. This time is timed and compared to the maximum defrosting interval. If the timed duration is less than the maximum defrosting interval, the predetermined defrosting time is determined according to the instructions issued by the data platform. If the timed duration is greater than or equal to the maximum defrosting interval, automatic defrosting is immediately initiated.

[0119] As can be seen, the current defrost interval is the time delayed from the baseline defrost interval to the current moment. The baseline defrost interval varies in different defrost cycles and is calculated by the refrigerator terminal using an intelligent defrost algorithm based on the refrigerator's operating status. Therefore, the current defrost interval reflects both the baseline interval and the time delayed to the current moment. This method avoids infinite delays and provides overall control over the defrost interval.

[0120] In practical scenarios, the method provided by the embodiments of the present invention is a defrosting control process under normal defrosting scenarios. The method provided by the embodiments of the present invention is not applicable to scenarios such as first defrosting, high-temperature defrosting, and energy consumption testing.

[0121] In real-world scenarios, if a Wi-Fi outage occurs during the delayed defrosting control process, the data platform will not resend the delayed defrosting command (i.e., the first delayed defrosting command or the second delayed defrosting command). Instead, defrosting will be performed at the previously determined scheduled defrosting time, such as the second scheduled defrosting time before this update.

[0122] In real-world scenarios, since the difference data originates from temperature data collected by sensors, there may be issues with the sensor's accuracy and stability. If the difference data between two adjacent time points fluctuates significantly, it indicates a problem with accuracy or stability, and such difference data can be discarded.

[0123] In real-world scenarios, the delay time should not be too long, and can be set to 2 hours to reduce the impact of sudden changes in refrigerator performance, such as a sudden door opening event.

[0124] In summary, the method provided by this invention performs delayed defrosting when the refrigerator's operating conditions are stable, and does not perform delayed defrosting when the operating conditions are unstable. Therefore, under stable operating conditions, the number of defrosting cycles can be reduced, thereby lowering the refrigerator's energy consumption. Reducing the number of defrosting cycles also reduces temperature fluctuations caused by the defrosting heater, preventing any impact on food preservation. Furthermore, it reduces the impact on the compressor's lifespan caused by the need for high-speed cooling after defrosting, thus extending the compressor's lifespan and reducing noise.

[0125] Secondly, embodiments of the present invention provide a defrosting control device based on difference extraction, the device being deployed on a data platform, and the device comprising:

[0126] The first extraction module is used to extract difference data within a first time period when it receives a first flag bit sent by the refrigerator terminal; wherein, the first time period is from the end of the last defrost to the time when the refrigerator terminal sends the first flag bit, the difference data is the difference between the freezer temperature and the evaporator temperature of the refrigerator terminal, the refrigerator terminal sends the first flag bit to the data platform through the Internet of Things platform at a preset time point before reaching the first predetermined defrost time, the first predetermined defrost time is obtained by adding a defrost reference interval time to the end of the last defrost; the defrost reference interval time is a reference value of the defrost interval time calculated by the refrigerator terminal based on the operating status of the refrigerator terminal;

[0127] The second extraction module is used to extract valid difference data from the difference data within the first time period according to the difference extraction rules; calculate the average value of the valid difference data within the first time period; calculate the average fluctuation value of the valid difference data within the first time period based on the average value; sum the average value and the average fluctuation value to obtain a standard value, and store the standard value; the standard value is used as the basis for determining whether further delayed defrosting is needed.

[0128] The first judgment module is used to determine whether the operation of the refrigerator terminal in the first time period hits the abnormal judgment rule in the performance auxiliary judgment rule based on the effective difference data in the first time period.

[0129] The first sending module is used to send the first delayed defrost instruction of the current defrost cycle to the refrigerator terminal through the IoT platform if any abnormal judgment rule is not hit, so that the refrigerator terminal can determine the second predetermined defrost time, and perform defrosting at the second predetermined defrost time if no further delayed defrost instruction is received before the second predetermined defrost time; after sending the first delayed defrost instruction, it also determines whether it is necessary to send a second delayed defrost instruction according to the standard value; wherein, the second predetermined defrost time is the first predetermined defrost time plus a delay time;

[0130] The second sending module is used to notify the refrigerator terminal to defrost at the first predetermined defrosting time if at least one of the anomaly judgment rules is met.

[0131] In one embodiment, the difference extraction rule includes at least one of the following: using the difference data of the compressor of the refrigerator terminal during its operation after being turned on as valid difference data; using the difference data of the evaporator temperature of the refrigerator terminal being lower than a preset temperature as valid difference data; using the difference data of the second time period after the defrost heater of the refrigerator terminal finishes heating as invalid difference data; using the difference data of the third time period after the door opening event occurs as invalid difference data; using the difference data of the fourth time period after the refrigerator door changes from the open state to the closed state as invalid difference data; wherein, the door opening event includes: any one of the door opening events corresponding to the refrigerator compartment, the freezer compartment, and the variable temperature compartment.

[0132] In one embodiment, the second extraction module is further configured to determine the preset temperature, the second time period, the third time period, and the fourth time period in the difference extraction rule through the following steps:

[0133] The system acquires the following data for the refrigerator terminal during the first time period: the temperature difference of each evaporator, the difference of the defrosting heater at different time points after it finishes working, the difference of the door opening event at different time points, and the difference of the refrigerator door at different time points after it switches from open to closed.

[0134] The outlier data of the refrigerator terminal during the first time period were removed by the box method, including the temperature difference of each evaporator, the difference of the defrost heater at different time points after the end of the work, the difference of the door opening event at different time points, and the difference of the refrigerator door at different time points after the refrigeration door was switched from open to closed.

[0135] Based on the evaporator temperatures during the first time period, determine the first range of values ​​for the evaporator temperature when the evaporator is in a stable period.

[0136] Based on the difference data at different time points after the defrosting heater finishes working, determine the changes in the difference data at different time points after the defrosting heater finishes working, and determine the second value range corresponding to the second time period based on the changes in the difference data at different time points after the defrosting heater finishes working.

[0137] Based on the difference data at different time points after the door opening event, determine the changes in the difference data at different time points after the door opening event, and determine the third value range corresponding to the third time period based on the changes in the difference data at different time points after the door opening event.

[0138] Based on the difference data at different time points after the refrigeration damper is switched from open to closed, the change of the difference data at different time points after the refrigeration damper is switched from open to closed is determined, and based on the change of the difference data at different time points after the refrigeration damper is switched from open to closed, the fourth value range corresponding to the fourth time period is determined.

[0139] Select the preset temperature from the first value range, select the second time period from the second value range, select the third time period from the third value range, and select the fourth time period from the fourth value range.

[0140] In one embodiment, the performance auxiliary judgment rule includes a first anomaly judgment rule, which includes: the compressor start-up rate of the refrigerator terminal is greater than 90% during the first time period, and the compressor speed exceeds a preset speed for a period of more than 60% of the time; wherein, if the difference data in the first time period matches the first anomaly judgment rule, it is determined that there is a peak on the change curve of the difference data of the refrigerator terminal in the first time period.

[0141] In one embodiment, the performance-assisted judgment rule includes a second anomaly judgment rule, which includes at least one of the following: the number of valid difference data within the first time period is less than a preset number; the average fluctuation value of the valid difference data within the first time period is greater than a preset value.

[0142] In one embodiment, the performance auxiliary judgment rule includes a third anomaly judgment rule, which includes: the current time is more than 8 hours away from the start time of the last defrost, the refrigeration time tn is greater than or equal to tmax × 1.8, and no refrigerator door opening event occurs during the current refrigeration cycle; wherein, the refrigeration time tn is calculated from the second start time of the compressor in the first refrigeration cycle after the end of the last defrost, until the end of the nth refrigeration cycle in which the current time is located; tmax is max(t2, t3); t2 is calculated from the end of two consecutive refrigeration cycles starting from the second refrigeration cycle; t3 is calculated from the end of two consecutive refrigeration cycles starting from the third refrigeration cycle; the refrigeration cycle is calculated from the end of one refrigeration cycle until the end of the next refrigeration cycle.

[0143] In one embodiment, the second extraction module is specifically used to: calculate the average fluctuation value using a first calculation formula, wherein the first calculation formula is:

[0144]

[0145] Where Ab is the average fluctuation value, n is the number of valid difference data within the first time period, and x1, x2, x3, ... x n The valid difference data within the first time period are represented by Ac, where Ac is the first average value.

[0146] In one embodiment, the first issuing module implements the step "after issuing the first delayed defrosting command, it also determines whether to issue a second delayed defrosting command based on the standard value" through the following unit:

[0147] The first extraction unit is used to obtain the difference data within a fifth time period when it receives the second flag bit sent by the refrigerator terminal, and to extract the valid difference data within the fifth time period; wherein, the fifth time period is from the time when the refrigerator terminal sends the first flag bit to the time when the refrigerator terminal sends the second flag bit; the refrigerator terminal sends the second flag bit to the data platform through the Internet of Things platform at a preset time point before the current second predetermined defrosting time;

[0148] The first calculation unit is used to calculate the average value of the effective difference data within the fifth time period, and to record the average value as the second average value.

[0149] The first judgment unit is used to determine whether the second average value is less than the standard value;

[0150] The first issuing unit is configured to: if so, issue a further delay defrosting instruction for the current defrosting cycle to the refrigerator terminal through the Internet of Things platform, so that the refrigerator terminal determines the second predetermined defrosting time after the current update, and performs defrosting at the second predetermined defrosting time after the current update if no further delay defrosting instruction is received before the second predetermined defrosting time after the current update. The second predetermined defrosting time after the current update is obtained by adding a delay time to the second predetermined defrosting time before the current update.

[0151] The second issuing unit is used to: otherwise, notify the refrigerator terminal through the Internet of Things platform to defrost at the second predetermined defrost time before this update.

[0152] In one embodiment, after receiving the instruction to delay defrosting again and determining the second predetermined defrosting time after this update, the refrigerator terminal is further configured to: calculate the current cumulative delay time within the current defrosting cycle, and determine whether the current cumulative delay time is less than the maximum delay time; if so, defrosting is performed at the second predetermined defrosting time after this update if no instruction to delay defrosting again is received before the second predetermined defrosting time after this update; otherwise, defrosting is performed at the second predetermined defrosting time before this update.

[0153] In one embodiment, the refrigerator terminal is further configured to: time the current defrost interval within the current defrost cycle, and determine whether the current defrost interval is greater than or equal to the maximum defrost interval; if so, automatically enter the defrost state.

[0154] It is understood that explanations, specific implementation methods, beneficial effects, examples, etc. of the contents of the apparatus provided in the embodiments of the present invention can be found in the corresponding parts of the method provided in the first aspect, and will not be repeated here.

[0155] The various embodiments in this specification are described in a progressive manner. Similar or identical parts between embodiments can be referred to mutually. Each embodiment focuses on describing the differences from other embodiments. In particular, the apparatus embodiments are basically similar to the method embodiments, so the description is relatively simple; relevant parts can be referred to the descriptions of the method embodiments.

[0156] Those skilled in the art will recognize that, in one or more of the examples above, the functions described in this invention can be implemented using hardware, software, widgets, or any combination thereof. When implemented in software, these functions can be stored in a computer-readable medium or transmitted as one or more instructions or code on a computer-readable medium.

[0157] The specific embodiments described above further illustrate the purpose, technical solution, and beneficial effects of the present invention. It should be understood that the above description is only a specific embodiment of the present invention and is not intended to limit the scope of protection of the present invention. Any modifications, equivalent substitutions, improvements, etc., made on the basis of the technical solution of the present invention should be included within the scope of protection of the present invention.

Claims

1. A defrosting control method based on differential extraction, characterized by, The method is executed by a data platform, and the method comprises: Upon receiving a first flag bit issued by a refrigerator terminal, difference data in a first time period is extracted; the first time period is from the end time of the last defrosting to the time when the first flag bit is issued by the refrigerator terminal, and the difference data is the difference between the temperature of the freezer compartment and the temperature of the evaporating compartment of the refrigerator terminal; the refrigerator terminal issues the first flag bit to the data platform through an Internet of Things platform at a preset time point before reaching a first predetermined defrosting time; the first predetermined defrosting time is obtained by adding a defrosting reference interval time to the end time of the last defrosting; and the defrosting reference interval time is a reference value of a defrosting interval time calculated by the refrigerator terminal according to the operation of the refrigerator terminal; According to a difference extraction rule, valid difference data is extracted from the difference data in the first time period; the average value of the valid difference data in the first time period is calculated; the average fluctuation value of the valid difference data in the first time period is calculated according to the average value; the average value and the average fluctuation value are summed to obtain a standard value, and the standard value is stored; and the standard value is used as a basis for judging whether the defrosting needs to be delayed again subsequently; According to the valid difference data in the first time period, it is judged whether the operation of the refrigerator terminal in the first time period meets an abnormal judgment rule in a performance auxiliary judgment rule; If none of the abnormal judgment rules is met, a first delayed defrosting instruction of the current defrosting cycle is issued to the refrigerator terminal through the Internet of Things platform, so that the refrigerator terminal determines a second predetermined defrosting time, and performs defrosting at the second predetermined defrosting time if no further delayed defrosting instruction is received before the second predetermined defrosting time; after the first delayed defrosting instruction is issued, it is further judged whether a further delayed defrosting instruction needs to be issued according to the standard value; and the second predetermined defrosting time is obtained by adding a delay time to the first predetermined defrosting time; If at least one abnormal judgment rule is met, the refrigerator terminal is informed by the Internet of Things platform to perform defrosting at the first predetermined defrosting time; After the first delayed defrosting instruction is issued, it is further judged whether a further delayed defrosting instruction needs to be issued according to the standard value, which comprises: Upon receiving a second flag bit issued by the refrigerator terminal, difference data in a fifth time period is obtained, and valid difference data in the fifth time period is extracted; the fifth time period is from the time when the first flag bit is issued by the refrigerator terminal to the time when the second flag bit is issued by the refrigerator terminal; and the refrigerator terminal issues the second flag bit to the data platform through the Internet of Things platform at a preset time point before the current second predetermined defrosting time; The average value of the valid difference data in the fifth time period is calculated, and the average value is recorded as a second average value; It is judged whether the second average value is less than the standard value; and If the second average value is less than the standard value, a further delayed defrosting instruction is issued to the refrigerator terminal through the Internet of Things platform. If yes, the IoT platform sends a defrosting delay command to the refrigerator terminal, so that the refrigerator terminal determines a second updated defrosting time and defrosts at the second updated defrosting time if no defrosting delay command is received before the second updated defrosting time, wherein the second updated defrosting time is obtained by adding a delay time to the second defrosting time before the update; Otherwise, the IoT platform sends a defrosting command to the refrigerator terminal, so that the refrigerator terminal defrosts at the second defrosting time before the update.

2. The method of claim 1, wherein, The difference extraction rule includes at least one of the following: the difference data of the compressor of the refrigerator terminal during the working period after being turned on is valid difference data; the difference data of the evaporator temperature of the refrigerator terminal less than a preset temperature is valid difference data; the difference data of the defrosting heater of the refrigerator terminal after heating for a second time period is invalid difference data; the difference data within a third time period after a door opening event occurs is invalid difference data; The difference data within a fourth time period after the refrigeration door is switched from an open state to a closed state is invalid difference data; wherein the door opening event includes any one of the door opening events of the refrigeration chamber, the freezer chamber and the variable temperature chamber.

3. The method of claim 2, wherein, The determination process of the preset temperature, the second time period, the third time period and the fourth time period in the difference extraction rule includes: Obtain the difference data of each evaporator temperature of the refrigerator terminal within the first time period, the difference data at different time points after the defrosting heater stops working, the difference data at different time points after a door opening event occurs, and the difference data at different time points after the refrigeration door is switched from open to closed; Perform outlier rejection on the difference data of each evaporator temperature of the refrigerator terminal within the first time period, the difference data at different time points after the defrosting heater stops working, the difference data at different time points after a door opening event occurs, and the difference data at different time points after the refrigeration door is switched from open to closed by boxplot method; Determine a first value range corresponding to the evaporator temperature when the evaporator is in a stable period according to the evaporator temperature within the first time period; Determine the change of the difference data at different time points after the defrosting heater stops working according to the difference data at different time points after the defrosting heater stops working, and determine a second value range corresponding to the second time period according to the change of the difference data at different time points after the defrosting heater stops working; Determine the change of the difference data at different time points after a door opening event occurs according to the difference data at different time points after the door opening event occurs, and determine a third value range corresponding to the third time period according to the change of the difference data at different time points after the door opening event occurs; According to the difference data corresponding to different time points after the cold air door is switched from open to close, the change of the difference data at different time points after the cold air door is switched from open to close is determined, and according to the change of the difference data at different time points after the cold air door is switched from open to close, the fourth time period corresponding to the fourth value range is determined. The first value range is selected to obtain the preset temperature, the second value range is selected to obtain the second time period, the third value range is selected to obtain the third time period, and the fourth value range is selected to obtain the fourth time period.

4. The method of claim 1, wherein, The performance auxiliary judgment rule includes a first abnormality judgment rule, and the first abnormality judgment rule includes that the starting rate of the compressor of the refrigerator terminal in the first time period is greater than 90%, and the time length ratio of the speed of the compressor exceeding the preset speed is greater than 60%; wherein, if the difference data in the first time period hits the first abnormality judgment rule, it is determined that there is a dot on the change curve of the difference data of the refrigerator terminal in the first time period.

5. The method of claim 1, wherein, The performance auxiliary judgment rule includes a second abnormality judgment rule, and the second abnormality judgment rule includes at least one of the following: The number of effective difference data in the first time period is less than a preset number; The average fluctuation value of the effective difference data in the first time period is greater than a preset value.

6. The method of claim 1, wherein, The performance auxiliary judgment rule includes a third abnormality judgment rule, and the third abnormality judgment rule includes: The current time is more than 8 hours away from the last defrosting start time, the cold storage refrigeration time tn is greater than or equal to tmax*1.8, and no cold storage room opening event occurs in the current cold storage refrigeration period; Wherein, the cold storage refrigeration time tn is from the 2nd start time of the compressor after the last defrosting ends to the end of the nth cold storage refrigeration period at the current time; tmax is max(t2, t3); t2 is from the 2nd cold storage refrigeration period to the end of the continuous two cold storage refrigeration periods; t3 is from the 3rd cold storage refrigeration period to the end of the continuous two cold storage refrigeration periods; the cold storage refrigeration period is from the stop of the cold storage refrigeration to the end of the next cold storage refrigeration.

7. The method of claim 1, wherein, The average fluctuation value is calculated by using a first calculation formula, and the first calculation formula is: wherein Ab is the average fluctuation value, n is the number of valid difference value data in the first time period, x1, x2, x3,... xn are valid difference value data in the first time period, and Ac is the average value of valid difference value data in the first time period. n wherein Ab is the average fluctuation value, n is the number of valid difference value data in the first time period, x1, x2, x3,... xn are valid difference value data in the first time period, and Ac is the average value of valid difference value data in the first time period.

8. The method of claim 1, wherein, After receiving the defrosting delay instruction again and determining the second predetermined defrosting time after the update, the refrigerator terminal is further configured to calculate the current cumulative delay time in the current defrosting period, and determine whether the current cumulative delay time is less than the maximum delay time; if yes, defrosting is performed at the second predetermined defrosting time after the update without receiving the defrosting delay instruction again before the second predetermined defrosting time after the update; otherwise, defrosting is performed at the second predetermined defrosting time before the update.

9. The method of claim 1, wherein, The refrigerator terminal is further configured to time the current defrosting interval time in the current defrosting period, and determine whether the current defrosting interval time is greater than or equal to the maximum defrosting interval time; if yes, the refrigerator terminal automatically enters the defrosting state.

10. A defrosting control device based on differential extraction, characterized by, The device is deployed in a data platform, and the device includes: The first extraction module is configured to extract difference data in a first time period when a first flag bit issued by a refrigerator terminal is received, wherein the first time period is from a last defrosting end time to a time when the first flag bit is issued by the refrigerator terminal, and the difference data is a difference between a freezing chamber temperature and an evaporating chamber temperature of the refrigerator terminal; the refrigerator terminal issues the first flag bit to a data platform through an Internet of Things platform at a preset time point before a first predetermined defrosting time; the first predetermined defrosting time is obtained by adding a defrosting reference interval time to the last defrosting end time; and the defrosting reference interval time is a reference value of a defrosting interval time calculated by the refrigerator terminal according to an operation condition of the refrigerator terminal. The second extraction module is configured to extract valid difference data from the difference data in the first time period according to a difference extraction rule, calculate an average value of the valid difference data in the first time period, calculate an average fluctuation value of the valid difference data in the first time period according to the average value, sum the average value and the average fluctuation value to obtain a standard value, and store the standard value; the standard value is used as a basis for judging whether to perform delayed defrosting again in the future. The first judgment module is configured to judge whether an operation condition of the refrigerator terminal in the first time period meets an abnormal judgment rule in a performance auxiliary judgment rule according to the valid difference data in the first time period. The first issuing module is configured to issue a first delayed defrosting instruction of a current defrosting cycle to the refrigerator terminal through the Internet of Things platform if none of the abnormal judgment rules is met, so that the refrigerator terminal determines a second predetermined defrosting time and performs defrosting at the second predetermined defrosting time if no delayed defrosting instruction is received before the second predetermined defrosting time; and the first issuing module is further configured to judge whether to issue a delayed defrosting instruction again according to the standard value after the first delayed defrosting instruction is issued; wherein the second predetermined defrosting time is obtained by adding a delay time length to the first predetermined defrosting time. The second issuing module is configured to notify the refrigerator terminal to perform defrosting at the first predetermined defrosting time through the Internet of Things platform if at least one of the abnormal judgment rules is met. The first issuing module implements the judgment whether to issue the delayed defrosting instruction again according to the standard value after the first delayed defrosting instruction is issued by the following unit: The first extraction unit is configured to obtain difference data in a fifth time period and extract valid difference data in the fifth time period when a second flag bit issued by the refrigerator terminal is received, wherein the fifth time period is from a time when the first flag bit is issued by the refrigerator terminal to a time when the second flag bit is issued by the refrigerator terminal; and the refrigerator terminal issues the second flag bit to the data platform through the Internet of Things platform at a preset time point before a current second predetermined defrosting time. The first calculation unit is configured to calculate an average value of the valid difference data in the fifth time period, and the average value is recorded as a second average value. The first judging unit is configured to judge whether the second average value is less than the standard value; The first issuing unit is configured to: if yes, issue a defrosting instruction again for defrosting cycle through the Internet of Things platform to the refrigerator terminal, so that the refrigerator terminal determines a second updated defrosting time, and defrosts at the second updated defrosting time if no defrosting instruction again is received before the second updated defrosting time, wherein the second updated defrosting time is obtained by adding a delay time to the second defrosting time before the update; The second issuing unit is configured to: if no, notify the refrigerator terminal to defrost at the second defrosting time before the update through the Internet of Things platform.

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