A method and system for controlling a refrigerated compartment

Abstract

The application relates to the technical field of defrosting of refrigeration compartments, in particular to a control method and system for a refrigeration compartment, wherein the method comprises the following steps: a first acquisition step, a first judgment step, a first execution step, a second acquisition step, a second judgment step, a second execution step and a third judgment step. The system comprises a processor and a memory in communication connection with the processor; the application can greatly reduce the equipment loss caused by frequent start-stop or misoperation, prolong the service life of the system, effectively prevent the compressor from being liquid struck and reduce the equipment failure risk through strict state judgment and orderly equipment start-stop; the overall operation state of the system is fully considered, the idle running or invalid running of the compressor and the barrel pump system is avoided, and according to similar system operation data statistics, the system energy consumption can be reduced through the cooperative control strategy.

Description

Technical Field

[0001] This application relates to the technical field of defrosting in cold storage compartments, and in particular to a control method and system for cold storage compartments. Background Technology

[0002] In cold chain logistics, food processing, and warehousing, cold storage rooms are core equipment for maintaining the low-temperature environment of goods. During the refrigeration process, frost gradually condenses on the surface of the evaporator coils inside, leading to decreased heat exchange efficiency and increased energy consumption. Therefore, regular defrosting is essential to ensure the efficient and stable operation of the refrigeration system. Currently, the most widely used method is electric defrosting based on fixed time intervals.

[0003] In existing technologies, defrosting control of cold storage compartments often employs simple timing control or combined with temperature-based auxiliary judgment. A typical control process is as follows: the system records the cumulative running time of the compressor, and when the running time reaches the preset defrosting interval (e.g., 4 hours), the electric defrosting program for the cold storage compartment is automatically started. Before starting defrosting, the system shuts off the liquid supply solenoid valve and the air cooler, then turns on the electric heater to defrost. After a fixed defrosting time, the heater is turned off and the system enters the draining stage, finally restoring cooling. The start and stop conditions of the entire process are relatively simple, mainly relying on time parameters.

[0004] However, the aforementioned existing technologies have significant drawbacks: First, due to their reliance on fixed operating time intervals, they cannot adapt to actual operating conditions such as changes in cargo throughput and fluctuations in ambient humidity within the warehouse. Under low load or low humidity conditions, the evaporator may not be severely frosted, but defrosting is still performed according to the fixed cycle, resulting in energy waste and exacerbating temperature fluctuations within the warehouse, affecting the quality of stored goods. Conversely, under high load or high humidity conditions, the evaporator may be severely frosted before the defrosting time, leading to a sharp drop in refrigeration efficiency and forcing the compressor to operate at high load for extended periods, increasing energy consumption and equipment wear. Second, due to the lack of coordinated judgment on the status of other cold rooms and the overall operating status of the compressor when starting and ending defrosting, multiple cold rooms may simultaneously enter the defrosting state, or the compressor may continue to operate even when there is no refrigeration demand. This not only reduces the overall energy efficiency of the system but may also shorten the equipment lifespan due to frequent start-stop shocks. Summary of the Invention

[0005] This application provides a method and system for controlling a cold storage room, which can at least partially solve the above-mentioned technical problems.

[0006] Firstly, this application provides a method for controlling a cold storage compartment, which adopts the following technical solution:

[0007] A method for controlling a cold storage room includes the following steps:

[0008] First acquisition: When the temperature of a certain cold storage compartment reaches the set upper temperature limit, acquire the operating status of the compressor;

[0009] First determination: Determine if at least one compressor can start; if yes, execute the first execution step; if no, wait for a query interval and then return to execute the first retrieval step.

[0010] First execution: Turn on the air cooler of the cold storage compartment, and after a first set time delay, turn on the liquid supply solenoid valve of the cold storage compartment, start timing the defrosting interval of the cold storage compartment, and send a start signal to the compressor and drum pump system.

[0011] Second acquisition: After the liquid supply solenoid valve is opened, acquire whether the temperature of the cold storage compartment has reached the lower limit of the control temperature.

[0012] Second determination: When the temperature of the cold storage compartment reaches the lower limit of the control temperature, determine whether there are other cold storage compartments in the refrigeration system where the cold storage compartment is located that are cooling down. If there are no other cold storage compartments in the system that are cooling down, send a stop signal to the tank pump system and close the liquid supply solenoid valve of the cold storage compartment, and stop the defrost interval timer for the cold storage compartment at the same time; if there are other cold storage compartments in the system that are cooling down, only close the liquid supply solenoid valve of the cold storage compartment and stop the defrost interval timer.

[0013] Second execution: After closing the liquid supply solenoid valve, delay for a second set time, and then turn off the air conditioner of the cold storage compartment;

[0014] Third judgment: After the air cooler is turned off, determine whether there are still cold rooms in the refrigeration system where the cold room is located. If so, when the temperature of the cold room reaches the lower limit of the control temperature, the second judgment is executed again. If not, a shutdown signal is sent to the compressor.

[0015] In the existing technology, the liquid supply solenoid valve is installed on the evaporator inlet pipe. It controls the supply and cut-off of refrigerant liquid to the evaporator by turning on or off the power. It is a key actuator that directly controls whether the cold storage compartment is refrigerated.

[0016] A cold air cooler typically refers to a combination of an evaporator and a fan. The fan drives air to flow through the evaporator for forced heat exchange, thereby achieving rapid cooling of the cold storage room.

[0017] The tank pump system is a forced liquid supply device suitable for medium and large refrigeration systems. It consists of a low-pressure circulating liquid storage tank and a pump. It can stably supply refrigerant liquid to multiple evaporators. Its start and stop will affect the refrigerant circulation of the entire system. Reasonable control of its start and stop is crucial for system energy saving.

[0018] The compressor is the "heart" of the refrigeration system, providing cooling power by compressing refrigerant vapor. Traditional fixed-frequency compressors frequently start and stop, resulting in high energy consumption and large temperature fluctuations. In contrast, variable-frequency compressors can continuously adjust the cooling capacity by regulating the speed, making them more energy-efficient and providing more precise temperature control.

[0019] By adopting the above technical solution, the system continuously monitors the temperature of the cold storage compartment. When the temperature reaches the set upper limit, the system first obtains the compressor's operating status instead of directly starting the refrigeration, reducing energy waste caused by blind starting. After confirming that there is a usable compressor, the system operates in the order of starting the evaporator first, then delaying before opening the liquid supply solenoid valve. This timing design ensures that the refrigerant in the evaporator is fully vaporized, effectively preventing liquid slugging from damaging the compressor. The shutdown process after the temperature reaches the target also emphasizes system coordination. By judging the status of other cold storage compartments, the system decides whether to send a shutdown signal to the drum pump system, achieving efficient use of resources.

[0020] The system employs a closed-loop control logic of "acquisition → judgment → execution" to ensure that every action is based on the real-time state of the system, rather than being triggered by a single condition. An orderly start-stop sequence is used: evaporator starts → delay → liquid supply solenoid valve opens. The evaporator runs first to establish air circulation, enabling the evaporator to exchange heat before refrigerant is injected. This effectively prevents large amounts of liquid refrigerant from entering the evaporator and being directly sucked into the compressor without being fully vaporized, thus avoiding "liquid slugging" accidents and protecting the compressor's core components. After the temperature reaches the target, all equipment is not immediately shut down; instead, it checks whether there are other cold storage compartments in the system that are cooling down. This ensures that the two core power units, the drum pump and the compressor, only operate when globally needed, avoiding frequent start-stops or idling due to local demand, greatly improving system energy efficiency and equipment lifespan.

[0021] In summary, firstly, by strictly judging the status and orderly starting and stopping of equipment, equipment wear and tear caused by frequent starts and stops or misoperation is significantly reduced, extending the system's service life and effectively preventing compressor liquid slugging, thus reducing the risk of equipment failure. Secondly, the introduction of a global status monitoring mechanism means that temperature control of individual refrigerator compartments is no longer conducted in isolation, but rather fully considers the overall system operating status, avoiding idling or ineffective operation of the compressor and drum pump system. According to statistics from similar system operation data, this collaborative control strategy can reduce system energy consumption. Thirdly, the design of simultaneous start-up of the defrost interval timing and the refrigeration process provides a data foundation for subsequent precise defrosting, solving the common problem of inaccurate defrost timing judgment in traditional systems.

[0022] Optionally, it also includes:

[0023] Fourth judgment: In the execution of the first execution step, after the liquid supply solenoid valve is opened and the defrosting interval starts timing, it is determined in real time whether the defrosting interval timing of the fan in this refrigeration system has reached the preset value. If so, the fifth judgment step is executed; otherwise, the refrigeration state is maintained.

[0024] Fifth judgment: Further determine whether the fans that have reached the defrost interval belong to the same cold storage room and the number exceeds one, or whether the total number of fans that have reached the defrost interval in this system exceeds two. If so, maintain the current cooling state of the system and do not perform defrost for the time being; if not, perform electric defrost for the cold storage fans that have reached the defrost interval.

[0025] Electric defrosting: Start the electric defrosting function and start the defrosting timer. During the defrosting timer, continuously check whether the evaporator fin temperature has reached the set upper limit. If it has, immediately turn off the electric defrosting device and stop the defrosting timer; otherwise, turn off the defrosting device after the set defrosting time has been reached.

[0026] By adopting the above technical solution, when multiple fans in the system simultaneously reach the defrosting conditions, the patent sets a temporary defrosting threshold of "more than one fan in the same room" or "more than two fans in the system." It recognizes that defrosting operations (especially electric defrosting) are high-power, high-heat-load processes; multiple simultaneous defrosting operations would instantly and significantly increase the system's heat and electrical load, potentially leading to excessive temperature fluctuations or circuit overload. This mechanism staggers the defrosting tasks in time, smoothing out system load peaks. The defrosting process no longer relies solely on time but introduces the physical parameter of "evaporator fin temperature reaching the set upper limit," which directly reflects the defrosting effect. The mechanism is as follows: after the frost melts, the heat generated by the electric heater directly acts on the fins, causing their temperature to rise rapidly; once the temperature reaches the target, defrosting stops, meaning the frost has completely melted, achieving "on-demand termination," avoiding continuous heating (over-defrosting) in a frost-free state, and saving energy.

[0027] Optionally, in the electric defrosting step, the defrosting duration of the electric defrosting timer is... The following formula is used to dynamically determine:

[0028] ;in, This is the preset base defrost time; This is the difference between the actual defrost interval and the preset defrost interval. This is the difference between the temperature of the refrigerator compartment and the set upper limit of temperature when defrosting begins; , All are preset positive coefficients.

[0029] By adopting the above technical solution, the defrosting time is no longer a fixed value, but is dynamically calculated based on the difference between the actual defrosting interval and the preset value, and the difference between the storage temperature at the start of defrosting and the upper limit. A large difference between the actual defrosting interval and the preset value indicates that the frost may be thicker, requiring an increase in defrosting time. A large difference between the storage temperature at the start of defrosting and the upper limit means that the storage temperature safety margin is large, and the defrosting time can be appropriately shortened. The solution provides a suitable defrosting time for the actual conditions of different cold storage rooms, improving defrosting accuracy and energy efficiency. In addition to reducing the number of devices defrosting simultaneously, the solution further optimizes the energy consumption and effect of a single defrosting process.

[0030] Optionally, in the fifth determination step, a defrosting priority weight W is calculated for each refrigerator compartment that has reached the defrosting interval to determine the order in which defrosting is performed. The calculation formula is as follows:

[0031]

[0032] in, This is the actual time for the defrosting interval of the room; The pre-set defrosting interval for this room; This is the current temperature of the room; Set an upper temperature limit for this room; This refers to the allowable temperature fluctuation range for this room; This refers to the number of defrost cycles in this room over the past 24 hours; This represents the average number of defrost events per day in the history of this room; , , These are preset weighting coefficients;

[0033] The system prioritizes the defrosting priority weight. The highest-level cold storage compartment performs the electric defrosting step.

[0034] By adopting the above technical solution, the weighting comprehensively considers the urgency of defrosting, the degree of temperature deviation, and the historical defrosting frequency; the system prioritizes defrosting the cold storage compartment with the highest weight; it ensures that the cold storage compartment that needs defrosting the most receives priority resources, preventing a decrease in refrigeration efficiency or damage to goods due to defrosting delays; a complete intelligent defrosting chain is formed, which avoids conflicts, prioritizes, and precisely controls the duration, greatly improving defrosting efficiency.

[0035] Optionally, the preset defrosting interval time This is a dynamic value, which is periodically optimized based on the historical operating conditions of the cold storage compartment using the following formula:

[0036] ;

[0037] in, The initial baseline defrost interval; This represents the average number of times the door to this room was opened per day during the most recent statistical period. This represents the average duration of a single door opening in that room during the most recent statistical period. This represents the average cargo load rate of the room during the most recent statistical period. The preset number of times the door can be opened; A reference value for the system's preset duration; , , This is the preset adjustment coefficient.

[0038] By adopting the above technical solutions, frequent door openings, long durations, and heavy cargo loads will introduce more humid and hot air, accelerating frost formation. Therefore, it is necessary to shorten the defrost interval. By adapting to the operating conditions from the source, the rigid fixed interval mode has been changed, making the defrost interval more in line with the actual usage intensity of the cold storage room. Defrost can be scheduled in advance under high-load conditions for preventive maintenance, preventing a sharp drop in refrigeration efficiency caused by severe evaporator frost. At the same time, the setting of the defrost interval and the execution of the defrost duration have been optimized, and the priority calculation has been made more accurate.

[0039] Optionally, the defrosting duration is modified using the following formula:

[0040] ;

[0041] in, , This represents the average number of times the door to this room was opened per day during the most recent statistical period. This represents the average duration of a single door opening in that room during the most recent statistical period. This represents the average cargo load rate of the compartment during the most recent statistical period. All are preset positive coefficients. The preset number of times the door can be opened; This is a reference value for the system's preset duration.

[0042] By adopting the above technical solution, strength compensation is used: This represents a "usage intensity factor." A larger factor indicates a greater total amount of warm, humid air entering the cold storage compartment, suggesting a thicker frost layer and potentially a more complex structure (e.g., containing more ice crystals). Therefore, additional defrosting time D is needed to ensure complete defrosting. For "hotspot" cold storage compartments with frequent goods movement, this provides more adequate defrosting support, preventing incomplete defrosting and ice buildup. It also ensures the dynamic defrosting time model maintains high accuracy under various operating conditions. The greater the recent usage intensity of the compartment, the greater the contribution of the correction term to the defrosting time. For specific cold storage compartments with frequent goods movement, additional defrosting time is added to effectively handle abnormal frost formation. Both the defrosting interval and duration are dynamically optimized based on usage intensity, resulting in a more comprehensive control strategy.

[0043] Optionally, in the first determination step, if the determination is negative, the first acquisition step is executed again after waiting for a preset cyclic query interval, wherein the time of the cyclic query interval is adjustable and is determined by the interval adjustment step;

[0044] Interval adjustment: Record the number of consecutive failures when the first judgment step is executed consecutively and the result is negative; the duration of the loop query interval is negatively correlated with the number of consecutive failures, that is, the more consecutive failures there are, the shorter the loop query interval becomes, until a preset minimum query interval is reached.

[0045] Optionally, after the interval adjustment step, an active scheduling step may also be included;

[0046] Active scheduling: When the number of consecutive failures reaches a preset forced start threshold, the system no longer waits for the query interval, but directly sends a forced start signal to a compressor in a ready state to start it; the ready state includes: compressors that have completed the shutdown protection interval or are in a low load standby state.

[0047] In the active scheduling step, if there are multiple compressors in a ready-to-use state, then the priority calculation step and the sorting and calling step are executed:

[0048] Priority Calculation: Calculate a priority coefficient P for each available compressor using the following formula:

[0049] ;

[0050] in: This represents the cumulative operating time of the compressor. The maximum recommended operating time of the compressor set for the system; This is the rated energy efficiency ratio of the compressor; This is the maximum value of the rated energy efficiency ratio of all compressors in the system; and These are the weighting coefficients, and ;

[0051] Sorted Invocation: The system invokes requests according to priority coefficients. A compressor call order list is generated in descending order of importance, and the compressor ranked first in the list is started first.

[0052] Optionally, if there are multiple compressors in a ready-to-go state, one of them is selected for forced start according to a preset compressor optimization strategy. The optimization strategy considers factors such as the compressor's cumulative running time and rated energy efficiency, and prioritizes starting compressors with shorter cumulative running time and higher rated energy efficiency.

[0053] By adopting the above technical solutions, the compressor startup process is upgraded from passive waiting to proactive, adaptive intelligent scheduling, ensuring that cooling demands can be responded to quickly, while optimizing the operating status of the compressor cluster. When consecutive compressor requests fail, it means that the cooling demand is more urgent. The system increases the response frequency by shortening the query interval, attempting to "capture" the moment when a compressor becomes available, reducing the average waiting time for cooling demands and improving the system response speed. When the number of failures is too high and dynamic queries still cannot solve the problem, the system triggers "skip-level operation." It defines a "ready-to-go state" (such as a standby compressor that has completed its protection interval), bypassing conventional availability judgment and directly forcing startup. This provides the system with a last resort to ensure high-priority demands under resource constraints, enhancing system reliability. By bypassing conventional judgment and forcibly starting a standby compressor, it ensures the execution of high-priority tasks. Priority is calculated based on cumulative running time (balanced wear) and rated energy efficiency (energy saving), prioritizing the startup of compressors with short running times and high energy efficiency. This helps extend the overall lifespan of the compressor cluster and improve system energy efficiency.

[0054] Secondly, the control system for a cold storage compartment provided in this application adopts the following technical solution:

[0055] A control system for a cold storage compartment includes: a processor, and a memory communicatively connected to the processor;

[0056] The memory is provided with a computer-readable storage medium, and a computer program is stored on the computer-readable storage medium.

[0057] When the processor processes the computer program stored on the computer-readable storage medium, it implements the control method for the cold storage compartment.

[0058] By adopting the above technical solution, this system is used to control the cold storage compartment.

[0059] In summary, this application includes at least one of the following beneficial technical effects:

[0060] 1. Firstly, through strict status judgment and orderly equipment start-up and shutdown, equipment wear caused by frequent start-ups or misoperations is significantly reduced, extending the system's service life and effectively preventing compressor liquid slugging, thus reducing the risk of equipment failure. Secondly, the introduction of a global status monitoring mechanism means that temperature control of individual refrigerator compartments is no longer conducted in isolation, but rather fully considers the overall system operating status, avoiding idling or ineffective operation of the compressor and drum pump system. According to statistics from similar system operation data, this collaborative control strategy can reduce system energy consumption. Thirdly, the design of simultaneous start-up of the defrost interval timing and the refrigeration process provides a data foundation for subsequent precise defrosting, solving the common problem of inaccurate defrost timing judgment in traditional systems.

[0061] 2. The defrosting time is no longer a fixed value, but is dynamically calculated based on the difference between the actual defrosting interval and the preset value, and the difference between the initial temperature and the upper limit of the storage temperature. A large difference between the actual defrosting interval and the preset value indicates that the frost may be thicker, requiring an increase in defrosting time. A large difference between the initial temperature and the upper limit of the storage temperature means that the storage temperature safety margin is large, and the defrosting time can be appropriately shortened. It provides just the right defrosting time for the actual conditions of different cold storage compartments, improving defrosting accuracy and energy efficiency. While reducing the number of devices defrosting simultaneously, it further optimizes the energy consumption and effect of a single defrosting process.

[0062] 3. For "hotspot" cold storage compartments with frequent goods movement, it provides more adequate defrosting support to prevent incomplete defrosting and ice buildup; it ensures the dynamic defrosting time model maintains high accuracy under various operating conditions; the greater the recent usage intensity of the compartment, the greater the increase in defrosting time from the correction term; for specific cold storage compartments with frequent goods movement, additional defrosting time is added to effectively handle abnormal frost formation; both the defrosting interval and defrosting duration are dynamically optimized based on usage intensity, resulting in a more comprehensive control strategy. Attached Figure Description

[0063] Figure 1 This is a flowchart of the cold storage compartment control method in Embodiment 1 of this application;

[0064] Figure 2 This is a flowchart of the cold storage room control method in Embodiment 2 of this application;

[0065] Figure 3 This is a flowchart of the cold storage room control scheme in Embodiment 7 of this application. Detailed Implementation

[0066] The following combination Figures 1 to 3 This application will be described in further detail.

[0067] This embodiment discloses a method for controlling a cold storage room.

[0068] Example 1: Refer to Figure 1The control method for cold storage compartments includes the following steps:

[0069] First acquisition: When the temperature of a certain cold storage compartment reaches the set upper temperature limit, acquire the operating status of the compressor;

[0070] First determination: Determine if at least one compressor can start; if yes, execute the first execution step; if no, wait for a query interval and then return to execute the first retrieval step.

[0071] First execution: Turn on the air cooler of the cold storage compartment, and after a first set time delay, turn on the liquid supply solenoid valve of the cold storage compartment, start timing the defrosting interval of the cold storage compartment, and send a start signal to the compressor and drum pump system.

[0072] Second acquisition: After the liquid supply solenoid valve is opened, acquire whether the temperature of the cold storage compartment has reached the lower limit of the control temperature.

[0073] Second determination: When the temperature of the cold storage compartment reaches the lower limit of the control temperature, determine whether there are other cold storage compartments in the refrigeration system where the cold storage compartment is located that are cooling down. If there are no other cold storage compartments in the system that are cooling down, send a stop signal to the tank pump system and close the liquid supply solenoid valve of the cold storage compartment, and stop the defrost interval timer for the cold storage compartment at the same time; if there are other cold storage compartments in the system that are cooling down, only close the liquid supply solenoid valve of the cold storage compartment and stop the defrost interval timer.

[0074] Second execution: After closing the liquid supply solenoid valve, delay for a second set time, and then turn off the air conditioner of the cold storage compartment;

[0075] Third judgment: After the air cooler is turned off, determine whether there are still cold rooms in the refrigeration system where the cold room is located. If so, when the temperature of the cold room reaches the lower limit of the control temperature, the second judgment is executed again. If not, a shutdown signal is sent to the compressor.

[0076] Specifically, during system initialization, the following key parameters need to be set. These parameters should be stored in the system's non-volatile memory and can be modified through the human-machine interface (HMI) or host computer software to adapt to different application scenarios.

[0077] The first set duration is 5 seconds, adjustable from 1 to 60 seconds. The main purpose of this delay is to allow the evaporator enough time to establish a stable airflow field after it starts, ensuring that the heat exchange process in the evaporator can start immediately. 5 seconds is enough for the fan to accelerate from a standstill to its rated speed and form a stable air pressure, without significantly affecting the cooling response speed. If the time is too short (<3 seconds), the air pressure may not be stable, and if it is too long (>10 seconds), the cooling start time will be unnecessarily delayed.

[0078] The second set duration is 20 seconds, adjustable from 1 to 60 seconds. The main purpose of this delay is to "blow out residual cold." After closing the liquid supply solenoid valve, there is still residual liquid refrigerant and cold air in the evaporator. Allowing the air cooler to continue running for 20 seconds fully utilizes this cold air, blowing it into the cold storage compartment. This also helps the evaporator fin temperature rise to near the storage temperature, reducing the possibility of surface condensation or even secondary frost. The 20-second setting is based on empirical values ​​for the heat capacity and airflow of most small and medium-sized air cooler evaporators.

[0079] Initial defrost interval: 1200 minutes (20 hours), with an adjustable range of 600-2400 minutes recommended. For cold storage facilities with relatively stable operating environments and infrequent door openings (such as -18℃ freezers), 20 hours is an empirically balanced point. It avoids frequent defrosting and energy waste caused by too short an interval, while also preventing excessive frost buildup and severe reduction in refrigeration efficiency caused by too long an interval. Users can adjust the interval within this range based on actual frost conditions (e.g., through observation or system efficiency reports).

[0080] Cooling operation time of the air conditioner: 0-2000 minutes. This is a safety protection timer. If a cold storage room runs continuously for more than 2000 minutes (about 33 hours) and still fails to reach the lower temperature limit, the system will forcibly stop the cooling of that room and issue an alarm. This usually means that there is a fault, such as abnormal liquid supply, heat load far exceeding the design value, or sensor failure, to prevent the equipment from running indefinitely without effect.

[0081] Specifically, the first acquisition and the first judgment: temperature sensors (usually Pt100 or NTC) continuously monitor the temperature of each cold storage compartment. ,when ≥ When the upper temperature limit is set, such as -19℃, the control logic is triggered; the control system queries the status word of the compressor controller through the communication bus (such as Modbus, CAN) to obtain the operating status, fault status and protection status of all compressors (such as whether the shutdown protection timer has ended).

[0082] The criteria for determining "can start": the compressor has no fault alarm, the compressor has completed a shutdown time that is greater than its minimum protection interval (usually 3-5 minutes), and the compressor's current load does not exceed its maximum allowable load.

[0083] First execution: The controller sends a closing signal to the air cooler contactor of the target cold storage compartment, and the air cooler starts; a timer named Timer1 is started, with a set value of 5 seconds.

[0084] After Timer1 finishes timing, the controller sends an open signal to the drive module of the liquid supply solenoid valve, energizing the solenoid valve to open and allowing refrigerant to flow into the evaporator; at the same time, it starts or resets the defrost interval timer for that compartment, making it start timing from 0.

[0085] Start-up commands are sent to the compressor system and the tank pump system via the communication bus. After receiving the signal, the tank pump system runs according to its own startup sequence (e.g., start the pump first, then open the replenishment valve).

[0086] Second acquisition and second judgment: After the liquid supply solenoid valve is opened, the system continuously monitors the temperature of the cold storage compartment. ,when ≤ When the temperature reaches the lower limit of the control temperature, such as -21℃, the judgment logic is triggered; the system queries the status of the liquid supply solenoid valves of all other cold storage compartments. If the liquid supply solenoid valve of any compartment is in the open state, it is determined that "there are other cold storage compartments in the system that are cooling down".

[0087] Branch decision execution: Case A: If no other compartments are cooling down, send a stop signal to the tank pump system, close the liquid supply solenoid valve of this compartment, and stop the defrosting interval timer of this compartment.

[0088] Scenario B: If other compartments are being cooled, only close the liquid supply solenoid valve of this compartment and stop the defrosting interval timer for this compartment.

[0089] Second execution: While closing the liquid supply solenoid valve, start a timer named Timer2 with a set value of 20 seconds; after Timer2 finishes timing, the controller disconnects the air cooler contactor, and the air cooler stops running.

[0090] Third judgment: After the air cooler is turned off, the system checks the status of the liquid supply solenoid valves in all refrigerator compartments again; if all are in the closed state, a shutdown signal is sent to the compressor system through the communication bus; after receiving the signal, the compressor controller will shut down according to the preset safety procedure.

[0091] This embodiment effectively prevents the risk of compressor liquid slugging by employing an orderly startup process of "starting the evaporator first, then delaying before opening the liquid supply solenoid valve." Shutdown judgment based on the global state avoids frequent start-stop of the compressor and drum pump system, reducing mechanical wear. The start-stop of the core power units (compressor and drum pump) depends solely on the presence of cooling demand within the system, completely eliminating the energy waste of "single-room cooling, global operation." The evaporator's "residual cooling" process fully utilizes the residual cooling capacity of the evaporator. The established "acquisition-judgment-execution" closed-loop control logic ensures that every control action is based on the real-time state of the system, improving the system's automation level and reliability.

[0092] Example 2, refer to Figure 2The difference between this embodiment and Embodiment 1 is that it also includes:

[0093] Fourth judgment: In the execution of the first execution step, after the liquid supply solenoid valve is opened and the defrosting interval starts to be counted, it is determined in real time whether the defrosting interval of the fan in this refrigeration system has reached the preset value. If so, the fifth judgment step is executed.

[0094] Fifth judgment: If the judgment is yes, then further judgment is made: whether the fans that have reached the defrost interval belong to the same cold storage room and the number is more than one, or the total number in this system is more than two. If yes, then the current cooling state of the system is maintained and defrosting is not performed for the time being; if no, then the electric defrosting step is performed on the cold storage fans that have reached the defrost interval.

[0095] Electric defrosting: Start the electric defrosting function and start the defrosting timer. During the defrosting timer, continuously check whether the evaporator fin temperature has reached the set upper limit. If it has, immediately turn off the electric defrosting device and stop the defrosting timer; otherwise, turn off the defrosting device after the set defrosting time has been reached.

[0096] Specifically, the fourth judgment is: defrosting demand monitoring. The system maintains a global defrosting demand list, which is updated in real time with the defrosting interval timer of each refrigerator compartment fan. During system runtime (especially after the "first execution" step), this list is traversed at fixed short intervals (e.g., every 10 seconds); for each item in the list... Determine whether it is .in This is the currently active dynamic defrosting interval for this compartment.

[0097] When any one or more are found If the condition is met, the fifth judgment step is triggered.

[0098] Fifth Judgment: Defrosting Conflict Avoidance. The system first groups and counts all fans that have reached the defrosting interval; the following two judgment rules are applied: Rule 1 (Single Compartment Conflict): Check if there are any fans in the same refrigerator compartment that have reached the defrosting interval. Rule 2 (System-level conflict): Check the total number of fans that have reached the defrost interval throughout the entire system. .

[0099] If either rule one or rule two is met, a defrost conflict is identified. The system will maintain the current cooling state, record the defrost request, but will not execute the defrost operation. The system will re-evaluate in the next judgment cycle (the next 10 seconds).

[0100] If no conflict rule is met, the system will allow defrosting and proceed to the "electric defrosting" step.

[0101] Among them, single room A cold storage room is typically equipped with multiple air coolers to distribute air evenly. If two or more of these air coolers are defrosted simultaneously, the local heat load on the room will surge, potentially causing a significant rise in storage temperature and affecting the quality of goods. This rule ensures that at least one air cooler remains in the same room to maintain the refrigeration cycle.

[0102] System level Electric defrosting is a high-power operation. The more devices defrosting simultaneously, the higher the peak power consumption of the system, potentially triggering grid overload protection. Limiting the number of devices defrosting simultaneously (maximum 2 in this example) can smooth out power peaks, reduce the impact on the power supply system, and ensure stable system operation. This threshold can be adjusted according to the transformer capacity on site.

[0103] Electric defrosting: Precise defrosting execution; defrosting preparation: Close the liquid supply solenoid valve of the target refrigerator compartment, and turn off its air conditioner after a 20-second delay; Defrosting start: Turn on the electric defrosting device of the compartment (usually a contactor-controlled electric heating element), and simultaneously start the defrosting timer. Its initial setting is the dynamic defrosting duration calculated according to the formula. .

[0104] Dual-condition monitoring and termination: Condition 1 (temperature priority): The system continuously monitors the fin temperature sensor readings of the evaporator. .once (The upper limit of fin temperature is usually set at 10~15℃), immediately turn off the electric defrosting device and terminate the process. .

[0105] Condition 2 (Time Backup): The system monitors simultaneously. If the timer reaches... ,but Not yet reached The system also shuts down the electric defrosting device. This serves as a safety backup to prevent defrosting from continuing indefinitely due to a temperature sensor malfunction.

[0106] Post-defrost procedure: After defrosting, the system enters the set dripping time (e.g., 3-5 minutes) to allow the melted water droplets to drip off naturally, and then restores the room to normal cooling standby state.

[0107] For example, a scenario: a large distribution center cold storage with four cold storage rooms (H, J, K, L), each equipped with two air coolers; the system parameters have been set according to the above implementation method.

[0108] Process: The system runs continuously throughout the night, with each room cooling alternately, and the defrost timer continuously accumulates; Defrost demand is triggered: at 5:00 AM, the system detects during the "fourth judgment" that:

[0109] Fan No. 1 in Room H ;

[0110] Fan No. 1 in Room J ;

[0111] Fan No. 1 in Room K (Not timed out);

[0112] Fan No. 1 in Room L ;

[0113] All No. 2 fans did not exceed the time limit;

[0114] Fifth judgment: Statistics: The total number of fans that have reached the defrosting interval is 3 (H1, J1, K1).

[0115] Application rules: Rule 1: No more than one fan in the same room needs defrosting;

[0116] Rule 2: Total number within the system , greater than or equal to the set threshold of 3.

[0117] Decision: The system determines that there is a defrosting conflict, and will not perform any defrosting for the time being, maintaining the cooling state;

[0118] Priority scheduling and sequential execution: The system will make another judgment in the next cycle (e.g., after 10 seconds), and the situation will remain the same.

[0119] At this point, the system calls the defrosting priority weight W calculation formula to sort the three wind turbines H1, J1, and L1.

[0120] Assume the priority after calculation is: (L1 compartment has the longest timeout and the highest current temperature).

[0121] Based on priority, the system adds only L1 fan to the defrosting execution queue. At this point, the total number of fans waiting to be defrosted becomes 1, and the conflict rule is no longer triggered.

[0122] Precise defrosting execution: The system performs the "electric defrosting" step on fan number 1 in room L.

[0123] The defrosting time can be set from 0 to 60 minutes, and can be adjusted as needed. The value is a fixed value. .

[0124] After defrosting was initiated, the evaporator fin temperature of the L1 fan reached [temperature value missing] at the 25-minute mark. The system immediately terminates defrosting; compared to a fixed duration, it saves 3 minutes of defrosting energy.

[0125] Cyclic processing: After L1 defrost is completed, the defrost fans in the system become H1 and J1 (a total of 2 units, which does not exceed the threshold).

[0126] The system then starts the highest priority fan J1 for defrosting, and finally defrosts the H1 fan.

[0127] By using this staggered defrosting method, the system always keeps the number of devices defrosting at the same time below two, perfectly avoiding power peak impacts and ensuring that all devices can receive timely maintenance.

[0128] Example 3: The difference between this example and Example 2 is that, in the electric defrosting step, the defrosting duration of the electric defrosting timer is... The following formula is used to dynamically determine:

[0129] ;in, This is the preset base defrost time; This is the difference between the actual defrost interval and the preset defrost interval. This is the difference between the temperature of the refrigerator compartment and the set upper limit of temperature when defrosting begins; , All are preset positive coefficients.

[0130] Specifically, this embodiment dynamically adjusts the defrosting duration to reduce energy consumption caused by a fixed duration; the dynamic formula of Embodiment 3 is seamlessly embedded in the "electric defrosting" step of Embodiment 2. Specifically: Triggering and conflict judgment: completely consistent with Embodiment 2. The system determines the next fan to perform defrosting (e.g., the highest priority L1 fan) through "fourth judgment" and "fifth judgment".

[0131] Dynamic time calculation: Before starting the electric defrosting device by closing the liquid supply solenoid valve of the L1 fan and the air cooler, the system automatically calls the dynamic formula of this embodiment to calculate... .

[0132] Defrosting Execution: The system activates the electric defrosting device for the L1 fan and sets the defrosting timer. The initial value is set to the calculated value. .

[0133] Dual-condition termination: The defrosting process is still constrained by both the upper limit of fin temperature and the dynamic defrosting time. As long as either condition is met, defrosting will stop immediately.

[0134] This collaborative mechanism ensures that the system not only intelligently decides "when to melt" and "for whom to melt," but also precisely controls "how long to melt," achieving advanced intelligence throughout the entire defrosting process.

[0135] in, (Basic defrosting time): This represents the reference time required to completely defrost the evaporator under standard operating conditions (i.e., moderate frost thickness and normal storage temperature); value: 15 minutes. This value is determined based on empirical data regarding evaporator coil size, electric heater power (typically 1-2 kW / unit), and moderate frost thickness. It serves as the benchmark for all dynamic calculations.

[0136] Adjustable range: 0-60 minutes, which can be adjusted according to different models of air coolers.

[0137] (Defrost interval timeout deviation): The difference between the actual defrost interval and the preset interval, used to indirectly estimate the frost thickness; Calculation formula: ;

[0138] This indicates the actual cumulative operating time (in minutes) of the fan from the end of the last defrost to the triggering of this defrost, and the time is only counted during cooling operation.

[0139] This indicates the current defrosting interval (in minutes) for the fan, which can be a fixed value (e.g., 1200 minutes).

[0140] Calculation logic: The higher the value, the longer the fan has been operating beyond its service life, and the thicker the frost layer on its evaporator surface is likely to be.

[0141] A (Timeout Compensation Coefficient): Unit timeout deviation ( The defrosting time to be compensated is set to 0.1 (unit: minutes / minute). That is, for every minute the actual defrosting interval exceeds the preset value, the defrosting time is increased by 0.1 minutes (6 seconds) from the base value. This coefficient reflects the relationship between the rate of frost growth and time. A value of 0.1 is a robust estimate, acknowledging that exceeding the time limit will lead to thicker frost layers while avoiding overcompensation. Coefficient A can be further optimized through regression analysis of historical data.

[0142] (Defrost Initiation Temperature Margin): The difference between the actual temperature of the refrigerator compartment and the set upper temperature limit at the start of defrosting, used to assess the system's tolerance to the temperature rise caused by defrosting; Calculation formula: ;

[0143] This indicates the measured average temperature (in °C) of the cold storage compartment at the moment the "electric defrosting" step begins.

[0144] This indicates the upper limit of the set temperature for the cold storage compartment (unit: °C); Calculation logic: A negative value, and the larger its absolute value, indicates a lower storage temperature and a greater safety margin to withstand the temperature rise caused by the intrusion of defrosting heat load. Therefore, the defrosting time can be appropriately shortened.

[0145] B (Temperature Compensation Coefficient): Represents the unit temperature margin ( The allowable reduction in defrosting time is 0.3 (unit: minutes / ℃). That is, for every 1℃ drop in the storage temperature below the set upper limit when defrosting begins, the defrosting time is reduced by 0.3 minutes (18 seconds) from the calculated value. This coefficient quantifies the impact of temperature safety margin on defrosting time. A value of 0.3 can ensure defrosting effect while making full use of the storage temperature buffer to save energy. Like coefficient A, B is also an empirical coefficient that can be fine-tuned in practice.

[0146] For example, consider a large distribution center cold storage facility with four cold storage compartments (H, J, K, L). The system, through conflict avoidance and priority scheduling, has decided to first defrost fan number 1 (L1) in compartment L. Pre-defrost parameter acquisition: Before preparing to defrost L1, the system reads the following real-time data:

[0147] Actual defrosting interval for L1 fan: 1230 minutes; Preset defrosting interval for L compartment: 1200 minutes; Instantaneous temperature at the start of defrosting in L compartment: -20.5℃; Upper limit of set temperature for L compartment: -19℃; Basic defrosting time: 25 minutes; Overtime compensation coefficient: 0.1; Temperature compensation coefficient: 0.3;

[0148] Dynamic defrosting time calculation:

[0149] Calculate the timeout deviation: ;

[0150] Calculate the temperature margin: ;

[0151] Calculate dynamic defrosting time: ;

[0152] System final settings The system can be set to multiples of 0.5 minutes.

[0153] Precise defrosting execution: The system closes the liquid supply solenoid valve of the L1 fan, and shuts down its air cooler after a 20-second delay. The electric defrosting device of L1 is activated, and the defrosting timer begins a countdown of 28.5 minutes.

[0154] Scenario 1 (Temperature-Priority Trigger): Assuming the evaporator of fan L1 has a normal amount of frost, at the 20-minute mark, the fin temperature sensor reading has reached the upper limit of the fin temperature. The system immediately terminates defrosting.

[0155] Scenario 2 (Time Backup Trigger): Assume that the L1 fan evaporator is experiencing abnormally severe frosting, or the ambient humidity is extremely high. Even after 28.5 minutes, the fin temperature is still only 5°C (below the upper limit temperature); for safety reasons, the system will also shut down the electric heating device to prevent indefinite heating due to sensor failure, and record this anomaly for maintenance and diagnostic purposes.

[0156] Example 4: The difference between this example and Example 3 is that, in the fifth judgment step, a defrosting priority weight W is calculated for each refrigerator compartment that has reached the defrosting interval to determine the order in which defrosting is performed. The calculation formula is as follows:

[0157] ;

[0158] in, This is the actual time for the defrosting interval of the room; The pre-set defrosting interval for this room; This is the current temperature of the room; Set an upper temperature limit for this room; This refers to the allowable temperature fluctuation range for this room; This refers to the number of defrost cycles in this room over the past 24 hours; This represents the average number of defrost events per day in the history of this room; , , These are preset weighting coefficients;

[0159] The system prioritizes the defrosting priority weight. The highest-level cold storage compartment performs the electric defrosting step.

[0160] Specifically, based on Example 3, this embodiment introduces a defrosting priority weight decision mechanism to intelligently determine the order of execution when multiple cold storage compartments need defrosting at the same time.

[0161] Detailed implementation of the defrost priority weight (W) calculation formula, core formula:

[0162] ;

[0163] This formula uses three dimensions of indicators—defrosting urgency, temperature deviation, and historical defrosting frequency—to calculate a comprehensive priority score for each room to be defrosted, ensuring that system resources are allocated preferentially to the rooms that need defrosting the most.

[0164] in, This is represented as the defrosting urgency factor, indicating the urgency of the defrosting requirement. The higher the ratio, the more severe the overrun, the thicker the frost may be, and the more urgent the need for intervention. This is the actual time for the defrosting interval of the room; The pre-set defrosting interval for this room.

[0165] The weight 'a' is set to 0.5. This factor is given the highest weight because the root cause of defrosting is the accumulation of frost over running time.

[0166] The ratio is expressed as a temperature deviation factor, which characterizes the degree of danger of the current temperature state of the room. The larger the ratio (the larger the absolute value of the negative number), the further the temperature deviates from the upper limit, and there is a larger safety margin. The smaller the ratio (close to 0 or positive), the temperature has approached or exceeded the upper limit, which is very dangerous.

[0167] This indicates the current measured average temperature of the room. This indicates the upper limit of the set temperature for this room; This indicates the permissible temperature fluctuation range for that room;

[0168] The weight b is 0.3. This factor is directly related to the safety of cargo storage and has a relatively high weight.

[0169] This represents the historical defrosting frequency factor, indicating the frequency of defrosting in this compartment recently. An excessively high ratio may indicate an anomaly in this compartment (such as a faulty door seal). Appropriately reducing its priority can balance resources and prevent it from excessively consuming defrosting resources.

[0170] This indicates the number of defrost cycles completed in that room over the past 24 hours. This represents the average number of defrost cycles per day in the history of this room (the recommended statistical period is 30 days).

[0171] The weight c is set to 0.2. This factor is used for balancing and optimization, and its weight is relatively low. This term is a subtractive term in the formula, meaning that if defrosting is too frequent recently, its priority will be reduced.

[0172] In the "fifth judgment" step, whenever a list of fans requiring defrosting is found, the system calculates the priority weight W of the compartment for each object in the list. The system then generates a defrosting execution queue according to the W values ​​from highest to lowest.

[0173] Example 5: The difference between this example and Example 4 is that the preset defrosting interval time... This is a dynamic value, which is periodically optimized based on the historical operating conditions of the cold storage compartment using the following formula:

[0174] ;

[0175] in, The initial baseline defrost interval; This represents the average number of times the door to this room was opened per day during the most recent statistical period. This represents the average duration of a single door opening in that room during the most recent statistical period. This represents the average cargo load rate of the room during the most recent statistical period. The preset number of times the door can be opened; A reference value for the system's preset duration; , , This is the preset adjustment coefficient.

[0176] Specifically, this embodiment aims to enable the defrost interval to have self-learning and self-adaptive capabilities, dynamically adjusting it according to the historical usage intensity of the cold storage compartment, thereby optimizing the defrost triggering timing from the source.

[0177] Formula for calculating dynamic defrosting interval: ;

[0178] Based on three key usage intensity indicators—average number of door openings per day, average door opening duration, and cargo load rate—the baseline defrosting interval was determined. Perform dynamic scaling.

[0179] This represents the baseline defrost interval, which is the initially set defrost interval, such as 1200 minutes. This indicates the average number of times the door to this room is opened per day within the most recent statistical period (e.g., 7 days). Recorded via a door magnetic switch; This indicates the average duration (in seconds) of a single door opening in that room during the most recent statistical period. This indicates the average cargo load rate (0%~100%) of this compartment during the most recent statistical period. It can be estimated using a load sensor or manually set based on the inbound order. , This represents the reference values ​​for the number of times the door is opened and the duration of the opening, set by the system, used for normalization, for example... , .

[0180] Adjustment coefficient , , These three coefficients are usually negative because the higher the intensity of use, the faster the frosting speed, and the defrosting interval should be shortened.

[0181] This is represented as a door opening frequency coefficient, with a value of -0.10. For every 100% of the reference value reached by the average daily number of door openings, the interval is shortened by 10% from the baseline. This represents the door opening time coefficient, with a value of -0.05. For every 100% of the reference value reached by the average door opening time, the interval is reduced by 5%. This is expressed as a load factor, with a value of -0.15. For every 100% load factor, the interval is shortened by 15%. A high load factor indicates that the cargo itself is breathing and carries more humid, hot air.

[0182] The system performs this formula calculation once at a relatively long interval (such as every 24 hours) to update the dynamic defrost interval that takes effect the next day for each cold storage compartment.

[0183] Example 6: The difference between this example and Example 5 is that the defrosting duration is modified according to the following formula:

[0184] ;

[0185] in, , This represents the average number of times the door to this room was opened per day during the most recent statistical period. This represents the average duration of a single door opening in that room during the most recent statistical period. This represents the average cargo load rate of the compartment during the most recent statistical period. All are preset positive coefficients. The preset number of times the door can be opened; This is a reference value for the system's preset duration.

[0186] Specifically, this embodiment enhances the dynamic defrosting time formula of Embodiment 3 by adding an intensity compensation term, making the defrosting time prediction more accurate under complex working conditions.

[0187] Formula for calculating enhanced defrost duration: ;

[0188] Among them, intensity factor is used By modifying the original calculation formula, a comprehensive usage intensity factor is introduced to directly quantify the impact of external damp heat load on the amount of frost and to positively compensate for the defrosting time.

[0189] This is expressed as the usage intensity factor, a dimensionless number that comprehensively reflects the additional damp heat load caused by opening doors and carrying goods. The larger the value, the higher the usage intensity, and it is inferred that the frost layer may contain more dense frost crystals or thin ice layers formed by repeated door opening, which will take longer to melt.

[0190] D represents the strength compensation factor, with a value of 2.0 (unit: minutes); this factor defines the level at which the usage intensity reaches the reference level (i.e., When this occurs, additional defrosting time is required. A value of 2.0 minutes means that under high-intensity usage conditions, the system will reserve more defrosting time to ensure thorough defrosting.

[0191] This formula completely replaces the formula in Example 3 and is embedded before the "electro-defrosting" step. The calculation process remains the same, but the factors are considered more comprehensively.

[0192] For example, scenario: A large fresh food logistics center has cold storage rooms Z (fruits and vegetables, 0℃), X (dairy products, 2℃), and V (frozen, -18℃). After the system has been running for a week, at 8:00 AM one morning, the fourth judgment found that all three rooms Z, X, and V had reached their respective defrost intervals.

[0193] Dynamic defrosting interval updates: The system automatically updates each room at 2:00 AM daily. .

[0194] Compartment Z (High Usage Intensity): , 40s ; calculated .

[0195] Room X (medium usage intensity): calculated ;

[0196] Compartment V (low usage intensity): calculated .

[0197] Priority weight calculation: Real-time data is shown in Table 1 below:

[0198] Table 1

[0199]

[0200] Calculate the weights W (a=0.5, b=0.3, c=0.2):

[0201] ;

[0202] ;

[0203] ;

[0204] The system generates defrosting queues V, X, and Z. Compartment C has the highest weight due to its large temperature margin. Furthermore, there have been few instances of frost melting in history.

[0205] Enhanced defrost time calculation: The system first performs defrost on compartment C;

[0206] Data Acquisition: ; ; ; ; ; ; , , ; .

[0207] .

[0208] .

[0209] The system is set to defrost for 26.0 minutes and is executing the defrost process. Since the frost buildup in compartment V is not severe, the defrost process may be terminated at 18 minutes due to fin temperature conditions.

[0210] Example 7: The difference between this example and Example 6 is that in the first judgment step, if the judgment is negative, the first acquisition step is executed again after waiting for a preset cyclic query interval. The cyclic query interval is adjustable and is determined by the interval adjustment step.

[0211] Interval adjustment: Record the number of consecutive failures when the first judgment step is executed consecutively and the result is negative; the duration of the loop query interval is negatively correlated with the number of consecutive failures, that is, the more consecutive failures there are, the shorter the loop query interval becomes, until a preset minimum query interval is reached.

[0212] Following the interval adjustment step, an active scheduling step is also included;

[0213] Active scheduling: When the number of consecutive failures reaches a preset forced start threshold, the system no longer waits for the query interval, but directly sends a forced start signal to a compressor in a ready state to start it; the ready state includes: compressors that have completed the shutdown protection interval or are in a low load standby state;

[0214] In the active scheduling step, if there are multiple compressors in a ready-to-use state, then the priority calculation step and the sorting and calling step are executed:

[0215] Priority Calculation: Calculate a priority coefficient P for each available compressor using the following formula:

[0216] ;

[0217] in: This represents the cumulative operating time of the compressor. The maximum recommended operating time of the compressor set for the system; This is the rated energy efficiency ratio of the compressor; This is the maximum value of the rated energy efficiency ratio of all compressors in the system; and These are the weighting coefficients, and ;

[0218] Sorted Invocation: The system invokes requests according to priority coefficients. A compressor call order list is generated in descending order of importance, and the compressor ranked first in the list is started first.

[0219] If there are multiple compressors in a ready-to-go state, one of them is selected for forced start according to a preset compressor optimization strategy. The optimization strategy considers factors such as the compressor's cumulative running time and rated energy efficiency, and prioritizes starting compressors with shorter cumulative running time and higher rated energy efficiency.

[0220] Specifically, this embodiment designs an adaptive scheduling strategy for compressor resource requests to ensure that cooling needs can be responded to quickly, while optimizing the operating status of the compressor cluster.

[0221] Interval adjustment steps: An algorithm combining exponential backoff and lower bound truncation is used to initially adjust the query interval. Set as (e.g., 30 seconds). The number of consecutive failures is counted if the "first judgment" result is negative (no available compressor). Add 1, and update the query interval as follows:

[0222] ; This indicates the initial query interval, with a value of 30 seconds, to avoid overloading the controller with excessively frequent queries.

[0223] This represents the shortest query interval, with a value of 5 seconds. When the demand is very urgent, frequent queries are performed at 5-second intervals, balancing response speed and system overhead.

[0224] This causes the interval to gradually shorten as the number of failures increases, exhibiting a "negative correlation" characteristic.

[0225] Active scheduling steps: Triggering condition: When the number of consecutive failures reaches a certain threshold. Reaching the forced start threshold It is triggered when (for example, 3 times).

[0226] "Ready-to-go" definition: The shutdown protection interval has been completed: the compressor shutdown time has exceeded its minimum protection time (usually 3-5 minutes).

[0227] Low-load standby state: For variable frequency compressors, if the current operating frequency is below a certain threshold (such as 25Hz), it indicates that its load is light and it is capable of taking on new loads.

[0228] Compressor priority calculation and sorting call:

[0229] Core formula: The two main objectives are to balance wear and tear (extending cluster lifespan) and operational energy efficiency (reducing system energy consumption).

[0230] This indicates the compressor's cumulative operating time, which can be read from the compressor controller or system log; This indicates the maximum recommended operating time of the compressor as set by the system, used for normalization. For example, it can be set to 20,000 hours. This indicates the compressor's rated energy efficiency ratio, a fixed value determined by the compressor model. This represents the maximum rated energy efficiency ratio of all compressors in the system;

[0231] Represents the weighting coefficient, and .recommend (Focusing on even wear) (Focusing on energy efficiency). This approach may slightly extend the overall lifespan, as maintenance costs are typically higher than the marginal electricity cost per run.

[0232] Once the "active scheduling" step is entered, the system lists all compressors in the "ready state", calculates the priority coefficient P for each compressor, generates a call list in descending order of P, and starts the compressor ranked first in the list.

[0233] For example, in the evening, the logistics cold storage experiences a peak in incoming goods. Due to a large influx of hot goods, the temperature in compartment M quickly rises to the set upper limit, triggering a cooling request. The first judgment: the system checks the compressor status and finds that compressors 1 and 2, which are currently running, are both at full capacity. System waiting. .

[0234] Further assessment: After 30 seconds, compressors 1 and 2 are still at full load. Update interval .

[0235] Third assessment: After 24 seconds, there is still no usable compressor. The interval was shortened to... .at this time The forced start threshold has been reached. .

[0236] Active scheduling and compressor selection: The system triggers "active scheduling" and scans for available compressors: it finds that compressor 3 (fixed frequency) and compressor 4 (variable frequency) are both in the shutdown protection completed state.

[0237] Data obtained: Compressor 3, cumulative operating time 8500 hours, rated energy efficiency ratio of compressor is 3.2; the maximum rated energy efficiency ratio of all compressors in the system is 3.5; Compressor 4, cumulative operating time 5200 hours, rated energy efficiency ratio of compressor is 3.5.

[0238] Calculate priority P, ,in, ;

[0239] ;

[0240] Compressor 4 has a higher P value, and the system forces compressor 4 to start to meet the emergency cooling needs of room M; this also achieves balanced wear (compressor 4, which has a shorter running time, is started first) and optimal energy efficiency (compressor 4, which has the highest energy efficiency, is started first).

[0241] This application embodiment also provides a control system for a cold storage compartment, including: a processor, and a memory communicatively connected to the processor;

[0242] The memory is provided with a computer-readable storage medium, and a computer program is stored on the computer-readable storage medium.

[0243] When the processor processes the computer program stored on the computer-readable storage medium, it implements the method for controlling the cold storage compartment.

[0244] The above are all preferred embodiments of this application, and are not intended to limit the scope of protection of this application. Therefore, all equivalent changes made in accordance with the structure, shape and principle of this application should be covered within the scope of protection of this application.

Claims

1. A method for controlling a cold storage compartment, characterized in that: Includes the following steps: First acquisition: When the temperature of a certain cold storage compartment reaches the set upper temperature limit, acquire the operating status of the compressor; First determination: Determine if at least one compressor can start; if yes, execute the first execution step; if no, wait for a query interval and then return to execute the first retrieval step. First execution: Turn on the air cooler of the cold storage compartment, and after a first set time delay, turn on the liquid supply solenoid valve of the cold storage compartment, start timing the defrosting interval of the cold storage compartment, and send a start signal to the compressor and drum pump system. Second acquisition: After the liquid supply solenoid valve is opened, acquire whether the temperature of the cold storage compartment has reached the lower limit of the control temperature. Second determination: When the temperature of the cold storage compartment reaches the lower limit of the control temperature, determine whether there are other cold storage compartments in the refrigeration system where the cold storage compartment is located that are cooling down. If there are no other cold storage compartments in the system that are cooling down, send a stop signal to the tank pump system and close the liquid supply solenoid valve of the cold storage compartment, and stop the defrost interval timer for the cold storage compartment at the same time; if there are other cold storage compartments in the system that are cooling down, only close the liquid supply solenoid valve of the cold storage compartment and stop the defrost interval timer. Second execution: After closing the liquid supply solenoid valve, delay for a second set time, and then turn off the air conditioner of the cold storage compartment; Third judgment: After the air cooler is turned off, it is determined whether there are still cold rooms in the refrigeration system where the cold room is located. If so, the second judgment is executed again when the temperature of the cold room reaches the lower limit of the control temperature. If not, a shutdown signal is sent to the compressor. Also includes: Fourth judgment: In the execution of the first execution step, after the liquid supply solenoid valve is opened and the defrosting interval starts timing, it is determined in real time whether the defrosting interval timing of the fan in this refrigeration system has reached the preset value. If so, the fifth judgment step is executed; otherwise, the refrigeration state is maintained. Fifth Judgment: Further determine whether the fans that have reached the defrost interval belong to the same cold storage room and the number exceeds one, or whether the total number of fans that have reached the defrost interval in this system exceeds two. If so, there is a defrost conflict. Maintain the current cooling state of the system and do not perform defrost for the time being. If it is still determined that there is a defrost conflict in the next judgment cycle, calculate the defrost priority weight W and perform defrost according to the priority weight W. If not, perform the electric defrost step for the cold storage fans that have reached the defrost interval. Electric defrosting: Start the electric defrosting function and start the defrosting timer. During the defrosting timer, continuously check whether the evaporator fin temperature has reached the set upper limit. If it has, immediately turn off the electric defrosting device and stop the defrosting timer; otherwise, turn off the defrosting device after the set defrosting time has been reached. In the fifth judgment step, a defrosting priority weight W is calculated for each refrigerator compartment that has reached the defrosting interval to determine the order in which defrosting is performed. The calculation formula is as follows: ； in, This is the actual time for the defrosting interval of the room; The pre-set defrosting interval for this room; This is the current temperature of the room; Set an upper temperature limit for this room; This refers to the allowable temperature fluctuation range for this room; This refers to the number of defrost cycles in this room over the past 24 hours; This represents the average number of defrost events per day in the history of this room; , , These are preset weighting coefficients; The system prioritizes the defrosting priority weight. The highest-level cold storage compartment performs the electric defrosting step.

2. The method for controlling a cold storage compartment according to claim 1, characterized in that: In the electric defrosting step, the defrosting duration of the electric defrosting timer. The following formula is used to dynamically determine: ;in, This is the preset base defrost time; This is the difference between the actual defrost interval and the preset defrost interval. This is the difference between the temperature of the refrigerator compartment and the set upper limit of temperature when defrosting begins; , All are preset positive coefficients.

3. The method for controlling a cold storage compartment according to claim 1, characterized in that: The preset defrosting interval time This is a dynamic value, which is periodically optimized based on the historical operating conditions of the cold storage compartment using the following formula: ； in, The initial baseline defrost interval; This represents the average number of times the door to this room was opened per day during the most recent statistical period. This represents the average duration of a single door opening in that room during the most recent statistical period. This represents the average cargo load rate of the room during the most recent statistical period. The preset number of times the door can be opened; A reference value for the system's preset duration; , , This is the preset adjustment coefficient.

4. The method for controlling a cold storage compartment according to claim 2 or 3, characterized in that: The defrosting duration is corrected using the following formula: ； in, , This represents the average number of times the door to this room was opened per day during the most recent statistical period. This represents the average duration of a single door opening in that room during the most recent statistical period. This represents the average cargo load rate of the compartment during the most recent statistical period. All are preset positive coefficients. The preset number of times the door can be opened; This is a reference value for the system's preset duration.

5. The method for controlling a cold storage compartment according to claim 4, characterized in that: In the first judgment step, if the judgment is negative, the first acquisition step is executed again after waiting for a preset cyclic query interval. The cyclic query interval is adjustable and is determined by the interval adjustment step. Interval adjustment: Record the number of consecutive failures when the first judgment step is executed consecutively and the result is negative; the duration of the loop query interval is negatively correlated with the number of consecutive failures, that is, the more consecutive failures there are, the shorter the loop query interval becomes, until a preset minimum query interval is reached.

6. The method for controlling a cold storage compartment according to claim 5, characterized in that: Following the interval adjustment step, an active scheduling step is also included; Active scheduling: When the number of consecutive failures reaches a preset forced start threshold, the system no longer waits for the query interval, but directly sends a forced start signal to a compressor in a ready state to start it; the ready state includes: compressors that have completed the shutdown protection interval or are in a low load standby state; In the active scheduling step, if there are multiple compressors in a ready-to-use state, then the priority calculation step and the sorting and calling step are executed: Priority Calculation: Calculate a priority coefficient P for each available compressor using the following formula: ； in: This represents the cumulative operating time of the compressor. The maximum recommended operating time of the compressor set for the system; This is the rated energy efficiency ratio of the compressor; This is the maximum value of the rated energy efficiency ratio of all compressors in the system; and These are the weighting coefficients, and ; Sorted Invocation: The system invokes requests according to priority coefficients. A compressor call order list is generated in descending order of importance, and the compressor ranked first in the list is started first.

7. The method for controlling a cold storage compartment according to claim 6, characterized in that: If there are multiple compressors in a ready-to-go state, one of them is selected for forced start according to a preset compressor optimization strategy. The optimization strategy considers factors such as the compressor's cumulative running time and rated energy efficiency, and prioritizes starting compressors with shorter cumulative running time and higher rated energy efficiency.

8. A control system for a cold storage compartment, characterized in that: include: A processor, and a memory communicatively connected to the processor; The memory is provided with a computer-readable storage medium, and a computer program is stored on the computer-readable storage medium. When the processor processes a computer program stored on the computer-readable storage medium, it implements the method as described in any one of claims 1-7.

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