Refrigeration systems and methods

Abstract

The application relates to a refrigeration system and method, which comprises a first refrigeration circuit, a second refrigeration circuit, a first refrigerant circuit and a second refrigerant circuit. The first refrigeration circuit comprises a first compressor, a first air heat exchanger and a first shell-and-tube heat exchanger. The second refrigeration circuit comprises a second compressor and a second air heat exchanger. The first refrigerant circuit is connected between the outlet of the first compressor and the inlet of the second air heat exchanger. The second refrigerant circuit is connected between the outlet of the second air heat exchanger and the inlet of the first shell-and-tube heat exchanger. When the first refrigeration circuit operates and the second refrigeration circuit is idle, after refrigerant flows out of the first compressor, part of the refrigerant sequentially flows through the first air heat exchanger and the first shell-and-tube heat exchanger, and the other part of the refrigerant sequentially flows through the first refrigerant circuit, the second air heat exchanger, the second refrigerant circuit and the first shell-and-tube heat exchanger. The application improves the refrigeration working efficiency of the refrigeration system under a low load working condition.

Description

Technical Field

[0001] This application relates to the field of multi-head refrigeration unit technology, and more particularly to a refrigeration system and method. Background Technology

[0002] Multi-unit air-cooled chillers are generally equipped with multiple independent refrigeration circuits, each with its own compressor, air heat exchanger, shell-and-tube heat exchanger, electronic expansion valve, and other components. Each circuit can be started and stopped independently. During the year-round operation, the building cooling load is low in the spring and autumn transition seasons. The unit often operates with only one or some refrigeration circuits running, while the remaining refrigeration circuits are idle and shut down, resulting in low refrigeration efficiency of the multi-unit air-cooled chiller. Summary of the Invention

[0003] This application provides a refrigeration system and method to improve the refrigeration efficiency of multi-head air-cooled chiller units.

[0004] In a first aspect, this application provides a refrigeration system, the system comprising: The first refrigeration circuit includes a first compressor, a first air heat exchanger, and a first shell-and-tube heat exchanger. The second refrigeration circuit includes a second compressor and a second air heat exchanger; The first refrigerant circuit is connected between the outlet of the first compressor and the inlet of the second air heat exchanger; The second refrigerant circuit is connected between the outlet of the second air heat exchanger and the inlet of the first shell-and-tube heat exchanger. When the first refrigeration circuit is running and the second refrigeration circuit is idle, after the refrigerant flows out from the first compressor, a portion of the refrigerant flows sequentially through the first air heat exchanger and the first shell and tube heat exchanger, while the other portion of the refrigerant flows sequentially through the first refrigerant circuit, the second air heat exchanger, the second refrigerant circuit, and the first shell and tube heat exchanger.

[0005] Optionally, the first refrigerant circuit includes a first valve, and the second refrigerant circuit includes a second valve; The first valve and the second valve are used to open when the first refrigeration circuit is running and the second refrigeration circuit is idle.

[0006] Optionally, the second refrigeration circuit includes a second shell-and-tube heat exchanger, and both the first refrigeration circuit and the second refrigeration circuit are provided with refrigerant recovery branches; The input end of the refrigerant recovery branch is connected to the air heat exchanger of the refrigeration circuit, and the output end of the refrigerant recovery branch is connected to the shell and tube heat exchanger of the refrigeration circuit. When the first refrigeration circuit is running and the second refrigeration circuit is idle, the refrigerant stored in the air heat exchanger in the second refrigeration circuit is returned to the second shell and tube heat exchanger for storage via its own refrigerant recovery branch. After the refrigerant recovery branch is closed, the first refrigerant circuit and the second refrigerant circuit are connected. The refrigerant flows out from the first compressor and is divided into two paths for heat exchange to complete the refrigeration cycle.

[0007] Optionally, the refrigerant recovery branch includes a third valve and a refrigerant pump connected in series along the refrigerant flow direction; The input end of the third valve is connected to the air heat exchanger of the refrigeration circuit, and the output end of the refrigerant pump is connected to the shell and tube heat exchanger of the refrigeration circuit.

[0008] Secondly, this application provides a refrigeration method, the method comprising: Monitor the operating status of the first compressor in the first refrigeration circuit and the operating status of the second compressor in the second refrigeration circuit; When the first compressor is running and the second compressor is stopped, the first refrigerant circuit and the second refrigerant circuit are connected so that the air heat exchanger in the second refrigeration circuit is connected in parallel to the first refrigeration circuit to participate in condensation heat exchange.

[0009] Optionally, connecting the first refrigerant circuit and the second refrigerant circuit includes: When the refrigerant recovery activation conditions are met, the refrigerant recovery branch in the second refrigeration circuit is activated. The refrigerant remaining in the second air heat exchanger in the second refrigeration circuit is controlled to be returned to the second shell-and-tube heat exchanger in the second refrigeration circuit for storage via the refrigerant recovery branch. When the refrigerant recovery shutdown conditions are detected, the refrigerant recovery branch in the second refrigeration circuit is shut down to terminate refrigerant recovery. If the continuous operating time of the first compressor in the first refrigeration circuit is greater than or equal to a preset time threshold, the second compressor in the second refrigeration circuit remains in a stopped state, and the refrigerant recovery branch in the first refrigeration circuit is closed, then the first refrigerant circuit and the second refrigerant circuit are connected.

[0010] Optionally, the refrigerant recovery activation conditions include: The continuous operating time of the first compressor in the first refrigeration circuit is greater than or equal to a preset time threshold. The duration of continuous shutdown of the second compressor in the second refrigeration circuit is greater than or equal to the preset duration threshold. The pressure difference in the first refrigeration circuit is greater than or equal to a preset pressure difference threshold, wherein the pressure difference is the pressure difference between the high pressure of the first compressor's exhaust and the low pressure of its intake.

[0011] Optionally, the refrigerant recovery shutdown condition is determined to be met if any of the following operating conditions are detected: The continuous operating time of the first compressor in the first refrigeration circuit is less than a preset time threshold. The duration of continuous shutdown of the second compressor in the second refrigeration circuit is less than the preset duration threshold. The pressure difference in the first refrigeration circuit is less than a preset pressure difference threshold.

[0012] Optionally, after monitoring the operating status of the first compressor in the first refrigeration circuit and the operating status of the second compressor in the second refrigeration circuit, the method further includes: When both the first compressor and the second compressor are running, the refrigerant recovery branch in the first refrigeration circuit and the second refrigeration circuit are closed, and the first refrigerant circuit and the second refrigerant circuit are also closed, so that the first refrigeration circuit and the second refrigeration circuit can each complete condensation heat exchange independently.

[0013] Thirdly, this application provides a refrigeration device, the device comprising: The monitoring module is used to monitor the operating status of the first compressor in the first refrigeration circuit and the operating status of the second compressor in the second refrigeration circuit. The conduction module is used to connect the first refrigerant circuit and the second refrigerant circuit when the first compressor is running and the second compressor is stopped, so that the air heat exchanger in the second refrigeration circuit is connected in parallel to the first refrigeration circuit to participate in condensation heat exchange.

[0014] Fourthly, this application provides a multi-head refrigeration unit, including the aforementioned refrigeration system.

[0015] Fifthly, this application provides an electronic device, comprising: at least one communication interface; at least one bus connected to the at least one communication interface; at least one processor connected to the at least one bus; and at least one memory connected to the at least one bus.

[0016] Sixthly, this application also provides a computer storage medium storing computer-executable instructions for performing the cooling method described in any of the preceding claims.

[0017] The technical solutions provided in this application have the following advantages compared with the prior art: This application adds a first refrigerant circuit and a second refrigerant circuit. When the first refrigeration circuit is running and the second refrigeration circuit is idle, the air heat exchanger of the second refrigeration circuit is connected in parallel to the first refrigeration circuit to work together. This expands the overall condensing heat exchange area of ​​the system, improves the problem of insufficient heat dissipation of a single heat exchanger under low load conditions, fully releases the heat dissipation potential of the original heat exchange hardware of the unit, greatly improves the utilization rate of the system's heat exchange resources, and thus improves the refrigeration efficiency of the refrigeration system under low load conditions. Attached Figure Description

[0018] The accompanying drawings, which are incorporated in and form part of this specification, illustrate embodiments consistent with this application and, together with the description, serve to explain the principles of this application.

[0019] To more clearly illustrate the technical solutions in the embodiments of this application 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.

[0020] One or more embodiments are illustrated by way of example with reference numerals in the accompanying drawings. These illustrations do not constitute a limitation on the embodiments. Elements with the same reference numerals in the drawings are denoted as similar elements. Unless otherwise stated, the figures in the drawings are not to be limited by scale.

[0021] Figure 1 A schematic diagram of a refrigeration system provided in an embodiment of this application; Figure 2 A schematic diagram of another refrigeration system provided in the embodiments of this application; Figure 3 A flowchart of a refrigeration method provided in an embodiment of this application; Figure 4 A flowchart illustrating the refrigerant recovery branch connection provided in this application embodiment; Figure 5 A flowchart illustrating the determination of refrigerant recovery activation conditions provided in this application embodiment; Figure 6 This is a schematic diagram of the structure of a refrigeration device provided in an embodiment of this application; Figure 7 This is a schematic diagram of the structure of an electronic device provided in an embodiment of this application.

[0022] Figure 2 In the middle, the components of the left refrigeration circuit are: compressor 1, air heat exchanger 2, electronic expansion valve 3, shell and tube heat exchanger 4, check valve 7, third valve 8, return gas 9, and refrigerant pump 10. The components of the refrigeration circuit on the right side are: compressor 1', air heat exchanger 2', electronic expansion valve 3', shell and tube heat exchanger 4', check valve 7', third valve 8', return gas 9', and refrigerant pump 10'. First valve 5, second valve 6. Detailed Implementation

[0023] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0024] The following disclosure provides numerous different embodiments or examples for implementing various structures of this application. To simplify the disclosure, specific examples of components and arrangements are described below. These are merely examples and are not intended to limit the scope of this application. Furthermore, reference numerals and / or letters may be repeated in different examples. Such repetition is for simplification and clarity and does not in itself indicate a relationship between the various embodiments and / or arrangements discussed.

[0025] Existing multi-compressor air-cooled chiller units are typically equipped with two completely independent first and second refrigeration circuits. Each refrigeration circuit is independently equipped with a compressor, check valve, air heat exchanger, electronic expansion valve, shell and tube heat exchanger, and return valve. Each refrigeration circuit can be started and stopped independently and serves as a backup for each other to adapt to different cooling load requirements.

[0026] The typical workflow of a single refrigeration circuit is as follows: After the compressor starts, it draws in low-temperature, low-pressure gaseous refrigerant and compresses it to form high-temperature, high-pressure gaseous refrigerant. The high-temperature, high-pressure gaseous refrigerant is discharged through a one-way valve. The high-pressure gaseous refrigerant then enters the air heat exchanger, where it releases heat through forced convection with the outside air, cooling and condensing into high-pressure liquid refrigerant. The condensed liquid refrigerant flows through the electronic expansion valve, where it is throttled and depressurized, transforming into low-temperature, low-pressure two-phase gas-liquid refrigerant. The low-temperature, low-pressure refrigerant enters the shell-and-tube heat exchanger, where it exchanges heat with the water medium inside the shell and tube, absorbing heat from the water side to achieve a cooling effect. The refrigerant itself absorbs heat and evaporates into low-temperature, low-pressure gaseous refrigerant. Finally, the gaseous refrigerant flows back to the compressor suction port through the return valve, completing a single complete refrigeration cycle.

[0027] When the unit is under high load, both refrigeration circuits start and operate simultaneously, each forming an independent refrigerant cycle. When the unit is under low load conditions, such as during the spring and autumn transition seasons, only one refrigeration circuit needs to be started and operated, while the other refrigeration circuit is shut down and idle. At this time, the first refrigeration circuit can only rely on its own air heat exchanger to complete condensation heat exchange, while the air heat exchanger of the second refrigeration circuit cannot participate in heat exchange work because the circuit pipelines are mutually closed, and remains in an idle state.

[0028] Under single-loop operation, the total condensing heat exchange area of ​​the entire unit cannot be fully utilized, resulting in low refrigeration efficiency of the refrigeration system. Based on this technical problem, this application provides a refrigeration system that adds a first refrigerant loop and a second refrigerant loop to the original multi-head air-cooled chiller unit.

[0029] The refrigeration system of this application includes: a first refrigeration circuit, a second refrigeration circuit, a first refrigerant circuit, and a second refrigerant circuit.

[0030] The first refrigeration circuit includes a first compressor, a first air heat exchanger, and a first shell-and-tube heat exchanger, which are connected in series to form an independent and complete refrigeration cycle. The second refrigeration circuit includes a second compressor and a second air heat exchanger, which together form an independent refrigeration cycle.

[0031] The first refrigerant circuit is a bridging connection pipe, with one end connected to the outlet of the first compressor and the other end connected to the inlet of the second air heat exchanger; the second refrigerant circuit is another bridging connection pipe, with one end connected to the outlet of the second air heat exchanger and the other end connected to the inlet of the first shell and tube heat exchanger.

[0032] When the first refrigeration circuit is running and the second refrigeration circuit is idle, the refrigerant flows out of the first compressor and is divided into two parallel flow paths: the first refrigerant flows through the first air heat exchanger and the first shell and tube heat exchanger in sequence to complete condensation and evaporation heat exchange; the second refrigerant flows through the first refrigerant circuit, the second air heat exchanger, and the second refrigerant circuit in sequence, and finally merges into the interior of the first shell and tube heat exchanger. The two refrigerant flows merge together to complete the refrigeration cycle.

[0033] Figure 1 The left side shows the first refrigeration circuit in operation, and the right side shows the second refrigeration circuit in idle state. The first refrigerant circuit has a first valve 5 connected in series inside, and the second refrigerant circuit has a second valve 6 connected in series inside. The first valve 5 and the second valve 6 are opened and closed synchronously and remain open only when the first refrigeration circuit is running and the second refrigeration circuit is idle and shut down.

[0034] Furthermore, the first refrigeration circuit of this application may include multiple first sub-refrigeration circuits, and the second refrigeration circuit may include multiple second sub-refrigeration circuits. Each sub-refrigeration circuit is equipped with a first valve 5 and a second valve 6. When the first sub-refrigeration circuit operates independently and the second sub-refrigeration circuit is in an idle or stopped state, the air heat exchangers of all idle second sub-refrigeration circuits can be connected in parallel to the currently operating first sub-refrigeration circuit through the first refrigerant circuit and the second refrigerant circuit to participate in condensation heat exchange together. There are no requirements for the positional adjacency between the multiple first sub-refrigeration circuits, nor are there any requirements for the positional adjacency between the multiple second sub-refrigeration circuits.

[0035] When the first refrigeration circuit includes a first sub-refrigeration circuit and the second refrigeration circuit includes a second sub-refrigeration circuit, the first valve and the second valve can be omitted. When the first refrigeration circuit is running and the second refrigeration circuit is idle, the refrigerant can flow directly through the first and second refrigerant circuits to complete the heat exchange without causing any operational hazards. When the first and second refrigeration circuits are running synchronously, the loads of the first and second refrigeration circuits are basically the same, and the refrigerant operating pressures inside them are roughly equivalent. There will be no significant refrigerant flow within the first and second refrigerant circuits. Even if there is a trace amount of refrigerant exchange, it will not adversely affect the normal refrigeration operation of the first and second refrigeration circuits.

[0036] When the unit is under high load, the first and second refrigeration circuits operate synchronously. The first and second refrigerant circuits remain closed, and the pipelines between the first and second refrigeration circuits are isolated from each other. The first and second refrigeration circuits each rely on their own compressors, air heat exchangers, electronic expansion valves, and shell and tube heat exchangers to form independent refrigerant circulation. The two refrigeration circuits do not interfere with each other and independently bear the unit's refrigeration load, thereby ensuring stable operation of the unit under high load conditions.

[0037] For example, Figure 1The left side shows the first refrigeration circuit in operation, and the right side shows the second refrigeration circuit inactive. The refrigerant flow process is as follows: The compressor 1 in the first refrigeration circuit compresses the low-temperature, low-pressure gaseous refrigerant and continuously discharges the high-temperature, high-pressure gaseous refrigerant. The high-temperature, high-pressure gaseous refrigerant first flows through the one-way valve 7 of the first refrigeration circuit. After passing through the one-way valve 7, the refrigerant is automatically split at the refrigerant inlet of the air heat exchanger 2, forming two independent refrigerant heat exchange paths. The first path of refrigerant flows directly into the air heat exchanger 2 of the first refrigeration circuit itself, where it undergoes forced convection heat exchange with the outside air, continuously releasing condensation heat to fully cool and condense the high-temperature, high-pressure gaseous refrigerant into high-pressure liquid refrigerant. The condensed high-pressure liquid refrigerant is directly delivered to the front end of the electronic expansion valve 3 of the first refrigeration circuit. The second path of high-temperature, high-pressure gaseous refrigerant is diverted across the circuit through the opened first valve 5 and precisely connected to the second refrigeration circuit. Inside the air heat exchanger 2', the unused air heat exchanger 2' in the second refrigeration circuit is fully utilized for auxiliary forced convection condensation heat exchange. This portion of the gaseous refrigerant is fully cooled and condensed into high-pressure liquid refrigerant in the air heat exchanger 2' of the second refrigeration circuit. Then, it is returned to the front end of the electronic expansion valve 3 of the first refrigeration circuit through the opened second valve 6. The two high-pressure liquid refrigerants that have completed sufficient condensation heat exchange are fully mixed and merged at the front end of the electronic expansion valve 3 of the first refrigeration circuit. The merged refrigerant is throttled and depressurized by the electronic expansion valve 3, and converted into low-temperature, low-pressure gas-liquid two-phase refrigerant. The low-temperature, low-pressure gas-liquid two-phase refrigerant continues to enter the shell-and-tube heat exchanger 4 of the first refrigeration circuit, where it evaporates and absorbs heat from the water side to complete the unit's refrigeration operation. The refrigerant itself is completely evaporated into low-temperature, low-pressure gaseous refrigerant. Finally, the gaseous refrigerant passes through the return gas valve that is opened simultaneously in the first refrigeration circuit ( Figure 1 (Not shown in the image) The air flows back to the suction port of compressor 1 to complete the refrigeration cycle.

[0038] This application adds a first refrigerant circuit and a second refrigerant circuit. When the first refrigeration circuit is running and the second refrigeration circuit is idle, the air heat exchanger of the second refrigeration circuit is connected in parallel to the first refrigeration circuit to work together. This expands the overall condensing heat exchange area of ​​the system, improves the problem of insufficient heat dissipation of a single heat exchanger under low load conditions, fully releases the heat dissipation potential of the original heat exchange hardware of the unit, greatly improves the utilization rate of the system's heat exchange resources, and thus improves the refrigeration efficiency of the refrigeration system under low load conditions.

[0039] When the first refrigeration circuit is running and the second refrigeration circuit is idle, refrigerant accumulates inside the air heat exchanger of the second refrigeration circuit. If the first and second refrigerant circuits are directly connected, a large amount of accumulated refrigerant will flood into the first refrigeration circuit, causing the refrigerant circulation volume of the first refrigeration circuit to exceed the standard and disrupting the original precise refrigerant ratio of the system. At the same time, after the refrigerant inside the air heat exchanger of the second refrigeration circuit is emptied, it will result in insufficient overall refrigerant reserves in the second refrigeration circuit. When the unit load increases and the second refrigeration circuit needs to be started, the second refrigeration circuit will lack sufficient refrigerant and will not be able to quickly establish a stable refrigeration cycle or respond to the cooling load demand in a timely manner.

[0040] To address the aforementioned problems, this application... Figure 1 In the refrigeration system shown, refrigerant recovery branches are independently set up in the first refrigeration circuit and the second refrigeration circuit. The refrigerant recovery branches corresponding to the two refrigeration circuits do not interfere with each other and can separately collect the liquid refrigerant trapped inside the air heat exchanger of the corresponding refrigeration circuit. The operation process will not interfere with the normal refrigerant circulation of the other refrigeration circuit.

[0041] Each refrigerant recovery branch includes a third valve and a refrigerant pump connected in series along the refrigerant flow direction; the input end of the refrigerant recovery branch, i.e., the input end of the third valve, is connected to the air heat exchanger of the corresponding refrigeration circuit, and the output end of the refrigerant recovery branch, i.e., the output end of the refrigerant pump, is connected to the shell and tube heat exchanger of the corresponding refrigeration circuit; the third valve, as the on / off control component of the refrigerant recovery branch, is used to open or close the refrigerant recovery branch, and the refrigerant pump provides power for refrigerant transportation. The two work together to form a refrigerant recovery and transportation path from the air heat exchanger to the shell and tube heat exchanger.

[0042] When the system is in operation of the first refrigeration circuit and the second refrigeration circuit is idle, the system first performs a refrigerant recovery operation on the second refrigeration circuit. After the refrigerant recovery branch is shut down, the first and second refrigerant circuits are then connected, so that the refrigerant completes the refrigeration cycle in two separate circuits.

[0043] The specific refrigerant recovery process is as follows: After the system determines that the refrigerant recovery activation conditions are met, it opens the third valve and refrigerant pump inside the second refrigeration circuit, opening the refrigerant recovery branch from the second air heat exchanger to the second shell-and-tube heat exchanger within the second refrigeration circuit. The liquid refrigerant accumulated in the second air heat exchanger flows sequentially through the opened third valve and the refrigerant pump under the power of the refrigerant pump, ultimately collecting and storing in the second shell-and-tube heat exchanger of the second refrigeration circuit. This process completely transfers the refrigerant retained inside the second air heat exchanger, emptying the accumulated liquid. After the refrigerant recovery operation of the second refrigeration circuit is completed, the system closes the third valve and refrigerant pump of the second refrigeration circuit, cutting off the refrigerant recovery branch and eliminating interference from the refrigerant recovery branch on refrigeration and heat exchange. After confirming that the refrigerant recovery branch is completely closed and there is no residual liquid in the second air heat exchanger, the system connects the first and second refrigerant circuits. The second air heat exchanger of the second refrigeration circuit is connected to the condenser side of the first refrigeration circuit for collaborative heat exchange. The refrigerant in the first refrigeration circuit is normally diverted, and there will be no problem with refrigerant ratio disorder.

[0044] The following is combined Figure 2 The process of the refrigerant recovery stage and the cross-loop coordinated heat exchange stage is explained.

[0045] Assuming the left side is the operating first refrigeration circuit and the right side is the idle second refrigeration circuit, if the refrigerant recovery start conditions are met, the refrigerant recovery stage begins. At this time, the first valve 5 in the first refrigerant circuit and the second valve 6 in the second refrigerant circuit remain closed. The third valve 8 and refrigerant pump 10 in the first refrigeration circuit are closed, while the third valve 8' and refrigerant pump 10' in the second refrigeration circuit are open. Liquid refrigerant accumulated inside the air heat exchanger 2' of the second refrigeration circuit flows sequentially through the third valve 8' and refrigerant pump 10' under the drive of the refrigerant pump 10', and is stably transported and collected to the shell and tube heat exchanger 4' of the second refrigeration circuit, gradually emptying the refrigerant retained inside the air heat exchanger 2'. After the refrigerant inside the air heat exchanger 2' of the second refrigeration circuit is fully recovered, the system closes the third valve 8' and refrigerant pump 10' of the second refrigeration circuit, completely cutting off the refrigerant recovery branch of the second refrigeration circuit and eliminating the interference of the refrigerant recovery branch on the overall refrigeration cycle. After confirming that the third valve 8' and refrigerant pump 10' are completely shut off and that there is no residual liquid in the air heat exchanger 2' of the second refrigeration circuit, the system releases the interlock control and simultaneously opens the first valve 5 and the second valve 6, connecting the liquid-free air heat exchanger 2' in parallel to the condenser side pipeline of the first refrigeration circuit. At this time, the refrigerant discharged from the compressor of the first refrigeration circuit is divided into two paths, which are simultaneously condensed through the air heat exchanger 2 of the first refrigeration circuit and the air heat exchanger 2' of the second refrigeration circuit, respectively. The refrigerant circulation ratio of the whole machine remains stable, and the air heat exchanger 2' of the second refrigeration circuit can be directly reused without causing refrigerant disorder faults.

[0046] This application, by setting refrigerant recovery branches in the first and second refrigeration circuits respectively, can collect the accumulated refrigerant in the air heat exchanger of the second refrigeration circuit in advance and store it in the second shell-and-tube heat exchanger. This avoids a sudden surge of accumulated refrigerant into the first refrigeration circuit, ensuring a stable refrigerant circulation volume in the first refrigeration circuit and improving the operational stability of the idle heat exchanger in parallel under low-load conditions. At the same time, the second shell-and-tube heat exchanger retains a sufficient amount of refrigerant, so that when the unit load increases and the second refrigeration circuit starts running, the second refrigeration circuit can quickly establish a complete refrigerant circulation, improving the unit's load switching response speed and operational reliability.

[0047] In addition, the refrigerant recovery branches of the first and second refrigeration circuits operate independently and do not affect each other. Under high load conditions, the first and second refrigeration circuits operate synchronously, and each refrigerant recovery branch remains closed throughout. Under low load conditions, only the first refrigeration circuit is running, and the refrigerant recovery branch of the second refrigeration circuit can be started as needed, taking into account both the stable operation performance of the unit under high load and the heat exchange and energy-saving effect under low load.

[0048] Based on the same technical concept, this application also proposes a refrigeration method applied to the above-mentioned refrigeration system, applied to the controller of the unit, such as... Figure 3 As shown, the method includes: Step 301: Monitor the operating status of the first compressor in the first refrigeration circuit and the operating status of the second compressor in the second refrigeration circuit; Step 302: When the first compressor is running and the second compressor is stopped, the first refrigerant circuit and the second refrigerant circuit are connected so that the air heat exchanger in the second refrigeration circuit is connected in parallel to the first refrigeration circuit to participate in condensation heat exchange.

[0049] In step 301, the unit controller collects the start and stop signals of the first compressor in the first refrigeration circuit and the second compressor in the second refrigeration circuit in real time. Based on the collected start and stop signals, the compressor operating status is identified. The compressor operating status is divided into two categories: running status and shutdown status. The unit controller can distinguish between the synchronous operation of the two compressors and the independent operation of a single compressor based on the respective operating status of the first compressor and the second compressor.

[0050] In step 302, when the unit controller determines that the first compressor is in the running state and the second compressor is continuously in the shutdown and idle state, the refrigeration circuit configured for the first compressor is used as the first refrigeration circuit, and the refrigeration circuit configured for the second compressor is used as the second refrigeration circuit.

[0051] The unit controller synchronously activates the first valve in the first refrigerant circuit and the second valve in the second refrigerant circuit, so that the air heat exchanger of the second refrigeration circuit is connected in parallel to the condenser side piping system of the first refrigeration circuit, and participates in refrigerant condensation heat exchange together with the air heat exchanger of the first refrigeration circuit itself; the high-temperature and high-pressure refrigerant discharged by the first compressor can be diverted to the two sets of air heat exchangers for synchronous heat dissipation, and the two sets of heat exchangers work together to complete the condensation heat exchange process, forming a refrigeration cycle mode of single compressor operation and dual heat exchanger synchronous heat dissipation.

[0052] This application can accurately distinguish between the high-load dual-compressor synchronous operation and the low-load operation of only the first compressor by real-time monitoring of the working status of the first compressor and the second compressor. Under the low-load operation of only the first compressor, the controller connects the first refrigerant circuit and the second refrigerant circuit, making full use of the heat exchange capacity of the idle air heat exchanger in the second refrigeration circuit. Without starting the second compressor or increasing the unit's input power consumption, the total condensing heat exchange area of ​​the whole unit can be increased, effectively improving the unit's refrigeration efficiency.

[0053] As an optional implementation, in step 302, before opening the first valve and the second valve, this embodiment adds a pre-judgment for refrigerant recovery and a secondary verification of the valve opening, including the following: Step S11: If the refrigerant recovery start-up conditions are met, control the refrigerant recovery branch in the second refrigeration circuit to be turned on; Step S12: Control the refrigerant remaining in the second air heat exchanger in the second refrigeration circuit to be returned to the second shell and tube heat exchanger in the second refrigeration circuit for storage via the refrigerant recovery branch; Step S13: When the refrigerant recovery shutdown condition is detected, control the refrigerant recovery branch in the second refrigeration circuit to shut down, so as to terminate refrigerant recovery; Step S14: If the continuous operating time of the first compressor in the first refrigeration circuit is greater than or equal to the preset time threshold, the second compressor in the second refrigeration circuit remains in the off state, and the refrigerant recovery branch in the first refrigeration circuit is closed, then the first refrigerant circuit and the second refrigerant circuit are connected.

[0054] The unit controller monitors the system operating parameters. When it determines that the refrigerant recovery start conditions are met, it controls the refrigerant recovery branch inside the second refrigeration circuit to open the third valve and refrigerant pump inside the second refrigeration circuit, thus starting the refrigerant recovery process in advance. With the help of the opened refrigerant recovery branch, the liquid refrigerant accumulated inside the second air heat exchanger is continuously transported and collected to the second shell and tube heat exchanger matched with the second refrigeration circuit for storage. The refrigerant remaining inside the second air heat exchanger is emptied in advance to prevent the refrigerant from entering the first refrigeration circuit and causing circulation abnormalities.

[0055] During the refrigerant recovery operation, the unit controller continuously monitors various operating parameters of the unit in real time. When the system meets the refrigerant recovery shutdown conditions, it immediately controls the shutdown of the refrigerant recovery branch in the second refrigeration circuit, that is, shuts down the third valve and refrigerant pump in the second refrigeration circuit, thus terminating the refrigerant recovery operation.

[0056] After the refrigerant recovery branch of the second refrigeration circuit is completely shut down and the liquid inside the second air heat exchanger is drained, the unit controller performs a secondary operating condition check. Only when all three conditions are met simultaneously are the first and second refrigerant circuits allowed to be simultaneously activated. These three conditions are: the continuous operating time of the first compressor in the first refrigeration circuit is greater than or equal to a preset time threshold; the second compressor in the second refrigeration circuit remains shut down; and the refrigerant recovery branch inside the first refrigeration circuit is closed. Once all conditions are met, the controller simultaneously opens the first valve in the first refrigerant circuit and the second valve in the second refrigerant circuit, connecting the second air heat exchanger of the second refrigeration circuit in parallel to the condenser side of the first refrigeration circuit to participate in the condensation heat exchange operation.

[0057] Specifically, in the first refrigeration circuit, the first compressor must be continuously running for a preset time threshold to ensure that the refrigerant circulation flow and internal pressure of the first refrigeration circuit are within a stable range, preventing system pressure disturbances caused by the addition of a new heat exchange path. In the second refrigeration circuit, the second compressor must be continuously shut down to confirm that the unit is operating under low-load conditions with the first refrigeration circuit operating alone. The refrigerant recovery branch within the first refrigeration circuit must remain closed, indicating that the first refrigeration circuit is operating without refrigerant recovery and that the pipeline conditions are stable. Only after all three conditions are simultaneously verified and passed will the first and second refrigerant circuits be connected. This fundamentally prevents a large influx of accumulated refrigerant from the second air heat exchanger into the first refrigeration circuit, preventing refrigerant imbalance in the system and ensuring a stable and controllable parallel heat exchange process for the second air heat exchanger.

[0058] For example, when the first refrigeration circuit is running and the second refrigeration circuit is idle, after the refrigerant recovery operation of the second refrigeration circuit is completed and the third valve 8' and refrigerant pump 10' are closed, if the following three conditions are met simultaneously, the controller will activate the first valve 5 and the second valve 6, thus connecting the first refrigerant circuit and the second refrigerant circuit. Figure 4 As shown, the first compressor 1 of the first refrigeration circuit is continuously turned on for ≥20 minutes, the second compressor 1' of the second refrigeration circuit remains off, the third valve 8 and refrigerant pump 10 of the first refrigeration circuit are closed, and the first valve 5 and the second valve 6 are turned on.

[0059] This application strictly follows a timing control logic that prioritizes refrigerant recovery, followed by verification of multiple operating conditions, and finally, connection of the cross-loop refrigerant circuit. First, the refrigerant recovery branch of the second refrigeration circuit is connected, transferring the refrigerant accumulated in the second air heat exchanger to the second shell-and-tube heat exchanger for storage. This prevents accumulated refrigerant from rushing into the first refrigeration circuit after the cross-loop refrigerant pipeline is connected, thus eliminating sudden changes in refrigerant flow and circulation disturbances. When the system meets the refrigerant recovery shutdown conditions, the refrigerant recovery branch of the second refrigeration circuit is promptly shut down, ending the recovery process. Only when all three conditions are met—the first compressor's operating time reaches the target, the second compressor stops, and the refrigerant recovery branch of the first refrigeration circuit is closed—are the first and second refrigerant circuits connected. This layered timing control completely separates the refrigerant recovery process from the cross-loop refrigerant connection process, preventing mutual interference between the two processes, reducing pressure fluctuations during unit operation, and improving the operational reliability of the second air heat exchanger participating in parallel condensation heat exchange under low-load conditions.

[0060] As an optional implementation, the refrigerant recovery activation conditions include the following three sub-conditions. The refrigerant recovery branch can only be activated when all three sub-conditions are met: the continuous on-time of the first compressor in the first refrigeration circuit is greater than or equal to a preset time threshold; the continuous off-time of the second compressor in the second refrigeration circuit is greater than or equal to a preset time threshold; and the pressure difference in the first refrigeration circuit is greater than or equal to a preset pressure difference threshold, where the pressure difference is the pressure difference between the high-pressure exhaust and low-pressure suction of the first compressor. The setting principles and specific parameters of each sub-condition are as follows: During the initial startup phase of the unit, the internal refrigerant distribution is uneven, and the pipeline pressure fluctuates significantly. If the refrigerant recovery branch is activated at this time, it will interfere with the normal refrigerant circulation of the first refrigeration circuit, easily causing operational instability. Therefore, the first activation condition is set: the continuous operating time of the first compressor in the first refrigeration circuit is greater than or equal to a preset time threshold. After this condition takes effect, it can ensure that the first refrigeration circuit completely overcomes the startup fluctuation phase, and the refrigerant flow, heat exchange status, and pressure parameters inside the circuit all enter a stable range. For example, the continuous operating time of the first compressor can be set to ≥20 minutes.

[0061] The second activation condition is: the continuous shutdown time of the second compressor in the second refrigeration circuit is greater than or equal to a preset time threshold. The purpose of setting this condition is to allow the second refrigeration circuit to fully complete shutdown and pressure relief, allowing the refrigerant inside the circuit to naturally settle and ensuring complete pressure balance in the pipeline. If the second compressor's shutdown time is insufficient, the circuit pressure is not balanced, and the refrigerant distribution is disordered, starting refrigerant recovery at this time will result in problems such as disordered recovery flow and incomplete refrigerant extraction. For example, the continuous shutdown time of the second compressor can be set to ≥20 minutes.

[0062] The third activation condition is: the pressure difference in the first refrigeration circuit is greater than or equal to a preset pressure difference threshold, where the pressure difference is defined as the pressure difference between the high pressure of the first compressor's exhaust and the low pressure of its suction. This condition is set to provide sufficient pressure margin for refrigerant recovery operations, offsetting pressure losses generated by the refrigerant pump and pipeline flow, ensuring stable refrigerant delivery flow, and preventing malfunctions such as insufficient recovery power, incomplete refrigerant extraction, and negative pressure in the pipeline caused by insufficient pressure difference. For example, the pressure difference in the first refrigeration circuit can be set to ≥ ΔP + 100 kPa, where ΔP is a customizable base pressure difference value, for example, 250 kPa.

[0063] Combination Figure 5 The procedure for determining the start-up conditions of refrigerant recovery is shown below, and is also referenced. Figure 2 The refrigeration system structure, when the unit is only running the first refrigeration circuit, if the following conditions are met simultaneously: the first compressor in the first refrigeration circuit is continuously on for ≥20 minutes, the second compressor 1' in the second refrigeration circuit is continuously off for ≥20 minutes, and the pressure difference P1 in the first refrigeration circuit is ≥△P+100kPa, then the refrigerant recovery start condition is met, and the controller opens the third valve 8 and refrigerant pump 10 of the first refrigeration circuit to start the refrigerant recovery branch.

[0064] This application sets all three conditions mentioned above as prerequisites for simultaneous refrigerant recovery, and imposes strict restrictions on the start-up conditions of the refrigerant recovery branch, which can avoid various operational hazards caused by starting refrigerant recovery under unstable unit conditions.

[0065] The first compressor's operating time is constrained to a certain standard: ensuring the long-term stable operation of the first refrigeration circuit, with refrigerant circulation, system pressure, and heat exchange conditions all tending to be stable, and preventing the recovery operation from disturbing the normal refrigeration of the first refrigeration circuit.

[0066] The second compressor shutdown time is constrained to ensure that the second refrigeration circuit is fully depressurized, the refrigerant settles evenly, the refrigerant state inside the second air heat exchanger is stable, the refrigerant recovery operation is thoroughly extracted, and residual liquid in the heat exchanger is avoided.

[0067] Ensure the pressure difference of the first refrigeration circuit meets the standard: provide sufficient power pressure difference for the refrigerant pump to deliver refrigerant, overcome pipeline resistance, and ensure that the refrigerant recovery branch continuously and stably draws and delivers refrigerant, preventing situations where the recovery process stops or is incomplete.

[0068] By constraining the three conditions, this application activates the refrigerant recovery branch of the second refrigeration circuit only when the first refrigeration circuit, the second refrigeration circuit, and the system pressure are all in a steady state. This not only regulates the refrigerant inside the second refrigeration circuit in advance, creating safe conditions for the subsequent parallel reuse of the second air heat exchanger, but also does not interfere with the normal refrigeration cycle of the first refrigeration circuit, effectively improving the refrigerant control accuracy and overall operational stability of the unit under low load conditions.

[0069] As an optional implementation, this application sets three operating conditions that meet the refrigerant recovery shutdown conditions. If any of the following operating conditions are detected, it is determined that the refrigerant recovery shutdown conditions are met: the continuous on-time of the first compressor in the first refrigeration circuit is less than a preset time threshold; the continuous off-time of the second compressor in the second refrigeration circuit is less than a preset time threshold; the pressure difference in the first refrigeration circuit is less than a preset pressure difference threshold.

[0070] During unit operation, various operating parameters are monitored in real time. If any of the following conditions are detected, the refrigerant recovery shutdown condition is deemed met, and the refrigerant recovery operation must be terminated: Condition 1: The continuous operating time of the first compressor in the first refrigeration circuit is less than a preset time threshold. This condition indicates that the first refrigeration circuit has just started and its overall operating condition is not yet stable. Continuing to operate the refrigerant recovery branch will disturb the normal refrigerant circulation of the first refrigeration circuit, easily causing abnormalities such as pressure fluctuations. Condition 2: The continuous shutdown time of the second compressor in the second refrigeration circuit is less than a preset time threshold. This condition indicates that the unit's cooling load is about to increase, and there is a need to start the second compressor and put the second refrigeration circuit into operation in a short time. Continuously extracting refrigerant from the second air heat exchanger will cause insufficient refrigerant reserves in the second shell-and-tube heat exchanger, which is not conducive to the rapid establishment of a stable cycle in the second refrigeration circuit. Condition 3: The pressure difference in the first refrigeration circuit is less than a preset pressure difference threshold. The pressure difference is the difference between the high pressure of the first compressor's exhaust and the low pressure of its suction. This operating condition indicates that the system's differential pressure margin for refrigerant delivery is insufficient, and it cannot overcome pipeline flow resistance. Continuing to recover refrigerant will result in malfunctions such as poor refrigerant delivery and abnormal negative pressure in the pipeline.

[0071] For example, combined Figure 2 In the refrigeration system structure, when only the first refrigeration circuit is running, if any of the following three conditions occur, it is determined that the refrigerant recovery shutdown condition is met, and the controller shuts off the third valve 8' and refrigerant pump 10' of the second refrigeration circuit: the first compressor in the first refrigeration circuit is continuously on for less than 20 minutes, the second compressor 1' in the second refrigeration circuit is continuously off for less than 20 minutes, and the pressure difference P1 of the first refrigeration circuit is less than ΔP.

[0072] This application employs a control logic that shuts down refrigerant recovery upon triggering any operating condition. This logic can identify scenarios unsuitable for continuous refrigerant recovery, such as fluctuations in unit operating conditions and load switching, in real time, and promptly shut down the refrigerant recovery branch to avoid disturbances to the normal operation of the first refrigeration circuit under unstable operating conditions. At the same time, it can predict the unit's load increase demand in advance and promptly stop collecting refrigerant inside the second refrigeration circuit, ensuring that the second shell and tube heat exchanger retains sufficient refrigerant. This allows for a rapid response to the cooling load when the second refrigeration circuit is started later, improving the safety and adaptability of the entire refrigerant recovery control process.

[0073] As an optional implementation, after monitoring the operating status of the first compressor in the first refrigeration circuit and the operating status of the second compressor in the second refrigeration circuit, the method further includes: when both the first compressor and the second compressor are in operation, controlling the refrigerant recovery branch in the first refrigeration circuit and the second refrigeration circuit to close, and controlling the first refrigerant circuit and the second refrigerant circuit to close, so that the first refrigeration circuit and the second refrigeration circuit can each independently complete condensation heat exchange.

[0074] The unit controller continuously monitors the operating status of the first compressor in the first refrigeration circuit and the second compressor in the second refrigeration circuit. After completing the monitoring, it executes the following control logic: When both the first and second compressors are detected to be running simultaneously, the controller controls the refrigerant recovery branches within the first and second refrigeration circuits to remain closed, and simultaneously controls the first and second refrigerant circuits to close synchronously. The refrigerant recovery branches are shut off by closing the internal third valve and the refrigerant pump. The first and second refrigerant circuits are isolated by closing the internal first and second valves. At this time, the pipelines between the first and second refrigeration circuits are completely isolated, and the two circuits are not connected to each other. Each circuit independently completes condensation heat exchange using its own air heat exchanger, forming two independent refrigerant cycles that do not interfere with each other, jointly bearing the high-load cooling demand of the unit.

[0075] This application, under high-load conditions where the first and second compressors operate synchronously, simultaneously shuts down all refrigerant recovery branches and the connected first and second refrigerant circuits, allowing the first and second refrigeration circuits to maintain a completely independent and unconnected operating mode. The refrigerant circulation and operating parameters within the two circuits will not interfere with each other, effectively ensuring stable and reliable operation of the unit under high-load conditions. The entire control logic can be adapted to the full-load operating range of the unit, enabling energy saving through parallel heat exchange of idle heat exchangers under low-load conditions, while also ensuring system stability during high-load synchronous operation of the two circuits.

[0076] This application provides an overall process for a refrigeration method, including the following steps.

[0077] Step 1: The controller monitors the operating and shutdown status of the first compressor in the first refrigeration circuit and the second compressor in the second refrigeration circuit in real time, and continuously identifies the current operating conditions of the unit.

[0078] Step 2: When the controller detects that both the first compressor and the second compressor are running, it closes the third valve and the refrigerant pump in the first refrigeration circuit and the second refrigeration circuit, and at the same time closes the first valve in the first refrigerant circuit and the second valve in the second refrigerant circuit. At this time, the pipelines of the first refrigeration circuit and the second refrigeration circuit are isolated from each other, and each independently completes the refrigerant circulation and condensation heat exchange to meet the high-load cooling demand of the unit.

[0079] Step 3: When the controller detects that the first compressor is running and the second compressor is stopped, it determines that the unit has entered a low-load operating condition and prepares to execute the control logic for reusing the air heat exchanger of the second refrigeration circuit.

[0080] Step 4: The controller collects the unit's operating parameters in real time and synchronously verifies the refrigerant recovery start conditions. The conditions are as follows: the first compressor in the first refrigeration circuit is continuously running for a specified time, the second compressor in the second refrigeration circuit is continuously shut down for a specified time, and the pressure difference in the first refrigeration circuit meets the standard.

[0081] Step 5: If all three refrigerant recovery activation conditions are met, the controller opens the third valve and refrigerant pump inside the second refrigeration circuit, and connects the refrigerant recovery branch of the second refrigeration circuit; the refrigerant accumulated inside the second air heat exchanger of the second refrigeration circuit is transported to the second shell and tube heat exchanger of the second refrigeration circuit for centralized storage through the refrigerant recovery branch.

[0082] Step 6: During the refrigerant recovery operation, the controller monitors the unit's operating status in real time. Once any refrigerant recovery shutdown condition is triggered, the controller immediately shuts off the third valve and refrigerant pump of the second refrigeration circuit, cuts off the refrigerant recovery branch, and terminates the refrigerant recovery operation.

[0083] Step 7: After the refrigerant recovery branch of the second refrigeration circuit is completely closed, the controller performs a secondary operating condition check to confirm that the first compressor continues to operate stably, the second compressor remains off, and the third valve and refrigerant pump inside the first refrigeration circuit are in the closed state.

[0084] Step 8: After all multiple operating condition verifications pass, the controller synchronously turns on the first valve and the second valve, connecting the first refrigerant circuit and the second refrigerant circuit, and connecting the second air heat exchanger of the second refrigeration circuit that has drained the accumulated liquid to the condenser side pipeline of the first refrigeration circuit in parallel.

[0085] Step 9: The refrigerant discharged from the first compressor is divided into two parallel condensing heat exchangers. One flows through the air heat exchanger of the first refrigeration circuit itself, and the other flows through the second air heat exchanger of the second refrigeration circuit. After the two refrigerants merge, the entire refrigeration cycle is completed, realizing the synergistic efficiency of the two heat exchangers under low load conditions.

[0086] Based on the same technical concept, this application provides a refrigeration device, such as... Figure 6 As shown, the device includes: The monitoring module 601 is used to monitor the operating status of the first compressor in the first refrigeration circuit and the operating status of the second compressor in the second refrigeration circuit. The conduction module 602 is used to connect the first refrigerant circuit and the second refrigerant circuit when the first compressor is running and the second compressor is stopped, so that the air heat exchanger in the second refrigeration circuit is connected in parallel to the first refrigeration circuit to participate in condensation heat exchange.

[0087] Optionally, the conduction module 602 is used for: When the refrigerant recovery activation conditions are met, the refrigerant recovery branch in the second refrigeration circuit is activated. The refrigerant remaining in the second air heat exchanger in the second refrigeration circuit is returned to the second shell-and-tube heat exchanger in the second refrigeration circuit via the refrigerant recovery branch for storage. When the refrigerant recovery shutdown conditions are detected, the refrigerant recovery branch in the second refrigeration circuit is shut down to terminate refrigerant recovery. If the continuous operating time of the first compressor in the first refrigeration circuit is greater than or equal to a preset time threshold, the second compressor in the second refrigeration circuit remains in a stopped state, and the refrigerant recovery branch in the first refrigeration circuit is closed, then the first refrigerant circuit and the second refrigerant circuit are connected.

[0088] Optionally, the conduction module 602 is specifically used for: The continuous operating time of the first compressor in the first refrigeration circuit is greater than or equal to a preset time threshold. The duration of continuous shutdown of the second compressor in the second refrigeration circuit is greater than or equal to a preset duration threshold. The pressure difference in the first refrigeration circuit is greater than or equal to a preset pressure difference threshold, where the pressure difference is the pressure difference between the high pressure of the first compressor's exhaust and the low pressure of its suction.

[0089] Optionally, the conduction module 602 is specifically used for: The continuous operating time of the first compressor in the first refrigeration circuit is less than a preset time threshold. The continuous shutdown time of the second compressor in the second refrigeration circuit is less than the preset time threshold; The pressure difference in the first refrigeration circuit is less than the preset pressure difference threshold.

[0090] Optionally, the device is also used for: When both the first compressor and the second compressor are running, the refrigerant recovery branch in the first refrigeration circuit and the second refrigeration circuit are closed, and the first refrigerant circuit and the second refrigerant circuit are also closed, so that the first refrigeration circuit and the second refrigeration circuit can each complete condensation heat exchange independently.

[0091] like Figure 7As shown, this application provides an electronic device including a processor 701, a communication interface 702, a memory 703, and a communication bus 704, wherein the processor 701, the communication interface 702, and the memory 703 communicate with each other through the communication bus 704.

[0092] Memory 703 is used to store computer programs.

[0093] In one embodiment of this application, the processor 701, when executing a program stored in the memory 703, implements the cooling method provided in any of the foregoing method embodiments.

[0094] This application also provides a computer-readable storage medium storing a computer program thereon, which, when executed by a processor, implements the steps of the cooling method provided in any of the foregoing method embodiments.

[0095] The device embodiments described above are merely illustrative. The units described as separate components may or may not be physically separate, and the components shown as units may or may not be physical units; that is, they may be located in one place or distributed across multiple network units. Some or all of the modules can be selected to achieve the purpose of this embodiment according to actual needs.

[0096] Through the above description of the embodiments, those skilled in the art can clearly understand that each embodiment can be implemented using software plus a general-purpose hardware platform, or of course, using hardware. Based on this understanding, the above technical solutions, in essence or the parts that contribute to the related technology, can be embodied in the form of a software product. This computer software product can be stored in a computer-readable storage medium, such as ROM / RAM, magnetic disk, optical disk, etc., and includes several instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) to execute the methods described in the various embodiments or some parts of the embodiments.

[0097] It should be understood that the terminology used herein is for the purpose of describing particular exemplary embodiments only and is not intended to be limiting. Unless the context clearly indicates otherwise, the singular forms “a,” “an,” and “described” as used herein may also include the plural forms. The terms “comprising,” “including,” “containing,” and “having” are inclusive and therefore indicate the presence of the stated features, steps, operations, elements, and / or components, but do not exclude the presence or addition of one or more other features, steps, operations, elements, components, and / or combinations thereof. The method steps, processes, and operations described herein are not construed as requiring them to be performed in a particular order described or illustrated unless the order of performance is explicitly indicated. It should also be understood that additional or alternative steps may be used.

[0098] The above description is merely a specific embodiment of this application, enabling those skilled in the art to understand or implement this application. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of this application. Therefore, this application is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features claimed herein.

Claims

1. A refrigeration system, characterized in that, The system includes: The first refrigeration circuit includes a first compressor, a first air heat exchanger, and a first shell-and-tube heat exchanger. The second refrigeration circuit includes a second compressor and a second air heat exchanger; The first refrigerant circuit is connected between the outlet of the first compressor and the inlet of the second air heat exchanger; The second refrigerant circuit is connected between the outlet of the second air heat exchanger and the inlet of the first shell-and-tube heat exchanger. When the first refrigeration circuit is running and the second refrigeration circuit is idle, after the refrigerant flows out from the first compressor, a portion of the refrigerant flows sequentially through the first air heat exchanger and the first shell and tube heat exchanger, while the other portion of the refrigerant flows sequentially through the first refrigerant circuit, the second air heat exchanger, the second refrigerant circuit, and the first shell and tube heat exchanger.

2. The refrigeration system according to claim 1, characterized in that, The first refrigerant circuit includes a first valve, and the second refrigerant circuit includes a second valve; The first valve and the second valve are used to open when the first refrigeration circuit is running and the second refrigeration circuit is idle.

3. The refrigeration system according to claim 1, characterized in that, The second refrigeration circuit includes a second shell-and-tube heat exchanger, and both the first refrigeration circuit and the second refrigeration circuit are equipped with refrigerant recovery branches; The input end of the refrigerant recovery branch is connected to the air heat exchanger of the refrigeration circuit, and the output end of the refrigerant recovery branch is connected to the shell and tube heat exchanger of the refrigeration circuit. When the first refrigeration circuit is running and the second refrigeration circuit is idle, the refrigerant stored in the air heat exchanger in the second refrigeration circuit is returned to the second shell and tube heat exchanger for storage via its own refrigerant recovery branch. After the refrigerant recovery branch is closed, the first refrigerant circuit and the second refrigerant circuit are connected. The refrigerant flows out from the first compressor and is divided into two paths for heat exchange to complete the refrigeration cycle.

4. The refrigeration system according to claim 3, characterized in that, The refrigerant recovery branch includes a third valve and a refrigerant pump connected in series along the refrigerant flow direction; The input end of the third valve is connected to the air heat exchanger of the refrigeration circuit, and the output end of the refrigerant pump is connected to the shell and tube heat exchanger of the refrigeration circuit.

5. A refrigeration method applied to the refrigeration system as described in claim 1, characterized in that, The method includes: Monitor the operating status of the first compressor in the first refrigeration circuit and the operating status of the second compressor in the second refrigeration circuit; When the first compressor is running and the second compressor is stopped, the first refrigerant circuit and the second refrigerant circuit are connected so that the air heat exchanger in the second refrigeration circuit is connected in parallel to the first refrigeration circuit to participate in condensation heat exchange.

6. The method according to claim 5, characterized in that, Connecting the first and second refrigerant circuits includes: When the refrigerant recovery activation conditions are met, the refrigerant recovery branch in the second refrigeration circuit is activated. The refrigerant remaining in the second air heat exchanger in the second refrigeration circuit is controlled to be returned to the second shell-and-tube heat exchanger in the second refrigeration circuit for storage via the refrigerant recovery branch. When the refrigerant recovery shutdown conditions are detected, the refrigerant recovery branch in the second refrigeration circuit is shut down to terminate refrigerant recovery. If the continuous operating time of the first compressor in the first refrigeration circuit is greater than or equal to a preset time threshold, the second compressor in the second refrigeration circuit remains in a stopped state, and the refrigerant recovery branch in the first refrigeration circuit is closed, then the first refrigerant circuit and the second refrigerant circuit are connected.

7. The method according to claim 6, characterized in that, The refrigerant recovery activation conditions include: The continuous operating time of the first compressor in the first refrigeration circuit is greater than or equal to a preset time threshold. The duration of continuous shutdown of the second compressor in the second refrigeration circuit is greater than or equal to the preset duration threshold. The pressure difference in the first refrigeration circuit is greater than or equal to a preset pressure difference threshold, wherein the pressure difference is the pressure difference between the high pressure of the first compressor's exhaust and the low pressure of its intake.

8. The method according to claim 6, characterized in that, If any of the following operating conditions are detected, it is determined that the refrigerant recovery shutdown condition is met: The continuous operating time of the first compressor in the first refrigeration circuit is less than a preset time threshold. The duration of continuous shutdown of the second compressor in the second refrigeration circuit is less than the preset duration threshold. The pressure difference in the first refrigeration circuit is less than a preset pressure difference threshold.

9. The method according to claim 5, characterized in that, After monitoring the operating status of the first compressor in the first refrigeration circuit and the operating status of the second compressor in the second refrigeration circuit, the method further includes: When both the first compressor and the second compressor are running, the refrigerant recovery branch in the first refrigeration circuit and the second refrigeration circuit are closed, and the first refrigerant circuit and the second refrigerant circuit are also closed, so that the first refrigeration circuit and the second refrigeration circuit can each complete condensation heat exchange independently.

10. A refrigeration device, characterized in that, The device includes: The monitoring module is used to monitor the operating status of the first compressor in the first refrigeration circuit and the operating status of the second compressor in the second refrigeration circuit. The conduction module is used to connect the first refrigerant circuit and the second refrigerant circuit when the first compressor is running and the second compressor is stopped, so that the air heat exchanger in the second refrigeration circuit is connected in parallel to the first refrigeration circuit to participate in condensation heat exchange.

11. A multi-head refrigeration unit, characterized in that, Includes the refrigeration system as described in claim 1.

12. An electronic device, characterized in that, It includes a processor, a communication interface, a memory, and a communication bus, wherein the processor, the communication interface, and the memory communicate with each other through the communication bus; Memory, used to store computer programs; A processor, when executing a program stored in memory, implements the method of any one of claims 5-9.

13. A computer-readable storage medium, characterized in that, The computer-readable storage medium stores a computer program that, when executed by a processor, implements the method described in any one of claims 5-9.

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