Refrigeration system control method, refrigeration system, electric appliance and storage medium

Abstract

The application relates to a refrigeration system control method, a refrigeration system, an electrical appliance and a storage medium. The refrigeration system comprises a cold air machine, a circulating condenser, a first condenser, a compressor, a filter, an electronic expansion valve, a four-way reversing valve and a cold storage; the circulating condenser is sequentially connected with the first condenser, the four-way reversing valve, the compressor, the cold air machine, the electronic expansion valve, and forms an outer ring channel; the circulating condenser is also sequentially connected with the cold storage and the filter, and forms an inner circulating air duct. The scheme provided by the application can guarantee constant temperature of the cold storage during defrosting, avoid secondary frost formation after defrosting, recover the cold energy generated by the condenser during defrosting, and reduce the risk of liquid-carrying operation of the compressor.

Description

Technical Field

[0001] This application relates to the field of electrical equipment technology, and in particular to a refrigeration system control method, a refrigeration system, electrical equipment, and a storage medium. Background Technology

[0002] When air coolers used in medium- and low-temperature cold storage are operating normally, the fins are prone to frost buildup. Frost or ice formation reduces both the heat exchange area and the airflow, leading to decreased unit efficiency and ineffective cooling. To address this, current defrosting methods include hot refrigerant defrosting with a four-way reversing valve, hot gas defrosting, and electric defrosting. Among these, hot refrigerant defrosting is widely used due to its advantages such as clean defrosting, short defrosting time, and energy savings.

[0003] In practice, after the unit has been running stably, a thick layer of frost tends to form under the evaporator. The principle of hot refrigerant defrosting is that after the compressor reverses direction, the high-temperature hot refrigerant inside the evaporator gradually melts the frost layer on the outside of the copper pipes. During this period, the temperature of the storage unit gradually rises until the defrosting process ends and the system switches to refrigeration mode. Additionally, during defrosting, the evaporator continuously generates high-temperature, high-humidity steam. When the system starts cooling, this high-humidity steam easily frosts again on the heat exchanger surface, forming secondary frost after defrosting. This results in cooling loss and reduces the energy efficiency of the system. Summary of the Invention

[0004] This application provides a refrigeration system control method, a refrigeration system, electrical equipment, and a storage medium to solve the technical problem that in existing refrigeration systems, the high humidity steam generated during the defrosting process easily condenses again and causes the storage temperature to rise.

[0005] In a first aspect, this application provides a refrigeration system control method applied to a refrigeration system, the refrigeration system including a cooler, a circulating condenser, a first condenser, a compressor, a filter, an electronic expansion valve, a four-way reversing valve, and a cold storage; the circulating condenser is sequentially connected to the first condenser, the four-way reversing valve, the compressor, the cooler, and the electronic expansion valve to form an outer loop channel; the circulating condenser is also sequentially connected to the cold storage and the filter to form an inner loop air duct; the refrigeration system control method includes: controlling the inner loop air duct to close when the refrigeration system performs a refrigeration function; and controlling the inner loop air duct to open when the refrigeration system performs a defrosting function.

[0006] In one embodiment, the circulating condenser includes a first damper, a second damper, a third damper, and a fourth damper; the refrigeration system control method includes: when the refrigeration system performs a refrigeration function, controlling the second damper and the fourth damper to close, the first damper and the third damper to open, the first channel of the circulating condenser to close, the circulating condenser to disconnect from the cold storage and the filter, and the internal circulation duct to close; when the refrigeration system performs a defrosting function, controlling the second damper and the fourth damper to open, the first damper and the third damper to close, the first channel of the circulating condenser to open, the circulating condenser to establish a connection with the cold storage and the filter, and the internal circulation duct to open.

[0007] In one embodiment, when the refrigeration system performs the defrosting function, controlling the opening of the internal circulation duct includes: detecting the average temperature and average humidity of each measuring point of the air cooler; and determining whether to control the opening of the internal circulation duct based on the average temperature and average humidity of each measuring point of the air cooler.

[0008] In one embodiment, determining whether to open the internal circulation duct based on the average temperature and average humidity at each measuring point of the air cooler includes: determining whether the average temperature at each measuring point of the air cooler reaches a first temperature value and whether the average humidity at each measuring point of the air cooler reaches a first humidity value; if the average temperature and average humidity at each measuring point of the air cooler reach the first temperature value and the average humidity at each measuring point of the air cooler reach the first humidity value, determining whether the outlet pipe temperature of the circulating condenser is higher than the average temperature at each measuring point of the air cooler; and if the outlet pipe temperature of the circulating condenser is higher than the average temperature at each measuring point of the air cooler, controlling the opening of the internal circulation duct.

[0009] In one embodiment, when the refrigeration system performs the defrosting function, the method further includes: detecting the air supply temperature of the internal circulation duct; determining the air supply temperature deviation based on the air supply temperature and a preset temperature setting value; reducing the air supply volume in the internal circulation duct when the air supply temperature deviation is greater than 0; and increasing the air supply volume in the internal circulation duct when the air supply temperature deviation is less than 0.

[0010] In one embodiment, when the refrigeration system performs the defrosting function, the method further includes: detecting the heat exchange temperature difference of the internal circulation duct; determining the heat exchange temperature difference deviation based on the heat exchange temperature difference and a preset heat exchange temperature difference setting value; increasing the opening of the electronic expansion valve to increase the evaporation temperature of the circulating condenser when the heat exchange temperature deviation is greater than 0; and decreasing the opening of the electronic expansion valve to reduce the evaporation temperature of the circulating condenser when the air supply temperature deviation is less than 0.

[0011] Secondly, this application also provides a refrigeration system, which includes a fan cooler, a circulating condenser, a first condenser, a compressor, a filter, an electronic expansion valve, a four-way reversing valve, and a cold storage unit. The circulating condenser is sequentially connected to the first condenser, the four-way reversing valve, the compressor, the fan cooler, and the electronic expansion valve to form an outer loop channel. The circulating condenser is also sequentially connected to the cold storage unit and the filter to form an inner loop air duct. The circulating condenser can control the inner loop air duct to close when the refrigeration system is performing a refrigeration function, and control the inner loop air duct to open when the refrigeration system is performing a defrosting function.

[0012] In one embodiment, the circulating condenser includes a first windshield, a second windshield, a third windshield, and a fourth windshield. When the second windshield and the fourth windshield are closed, and the first windshield and the third windshield are open, the first channel of the circulating condenser is closed, the circulating condenser is disconnected from the cold storage and the filter, and the internal circulation duct is closed. When the second windshield and the fourth windshield are open, and the first windshield and the third windshield are closed, the first channel of the circulating condenser is open, the circulating condenser is connected to the cold storage and the filter, and the internal circulation duct is open.

[0013] Thirdly, this application also provides an electrical device, which includes the refrigeration system described in any of the above claims.

[0014] Fourthly, this application also provides a storage medium storing a computer program, which, when executed by a processor, implements the steps of any of the methods described above.

[0015] Compared with the prior art, the technical solution provided in this application has the following advantages: In the solution provided in this application, the circulating condenser is connected to both the inner and outer circulation ducts. During system refrigeration operation, the circulating condenser is connected to the outer circulation duct and participates in condensation and heat release as a normal condenser. During system defrosting operation, the circulating condenser is connected to the inner circulation duct, and the high-temperature and high-humidity steam in the cold storage enters the inner circulation duct, exchanges heat with the low-temperature refrigerant in the circulating condenser, and then returns to the cold storage. This embodiment can cool and dehumidify the high-temperature and high-humidity steam during the defrosting process, and then send the cooled and dehumidified air back into the cold storage, which can avoid secondary frosting during the defrosting process, maintain a constant storage temperature during the defrosting process, recover the cold energy generated by the condenser during the defrosting process, and reduce the risk of the compressor operating with liquid. Attached Figure Description

[0016] The accompanying drawings, which are incorporated in and form part of this specification, illustrate embodiments consistent with the invention and, together with the description, serve to explain the principles of the invention.

[0017] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, those skilled in the art can obtain other drawings based on these drawings without creative effort.

[0018] 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.

[0019] Figure 1 A schematic diagram of the outer ring channel connection structure in a refrigeration system provided in this application embodiment;

[0020] Figure 2 A schematic diagram of the internal circulation air duct connection structure in a refrigeration system provided in this application embodiment;

[0021] Figure 3 This is a schematic flowchart of a refrigeration system control method provided in an embodiment of this application;

[0022] Figure 4 A schematic diagram of the internal circulation air duct control process in a refrigeration system provided in this application embodiment;

[0023] Figure 5 This is a schematic diagram of an electrical device structure provided in an embodiment of this application.

[0024] The annotations in the attached figures are explained as follows:

[0025] 101 is the air cooler; 102 is the circulating condenser; 103 is the first condenser; 104 is the compressor; 105 is the filter; 106 is the cold storage; 1 is the electronic expansion valve; 2 is the four-way reversing valve; F1 and F2 are the internal circulation air intakes; F3 is the internal circulation air supply; S1 is the first windshield; S2 is the second windshield; S3 is the third windshield; S4 is the fourth windshield. Detailed Implementation

[0026] 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.

[0027] The following disclosure provides numerous different embodiments or examples for implementing various structures of the invention. 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 the invention. 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.

[0028] To address the technical problem that existing refrigeration systems often experience secondary frosting and increased storage temperature due to the high humidity vapor generated during the defrosting process, this application provides a refrigeration system control method, refrigeration system, electrical equipment, and storage medium. This method can prevent secondary frosting during the defrosting process, maintain a constant storage temperature during defrosting, recover the cold energy generated by the condenser during defrosting, and reduce the risk of the compressor operating with liquid.

[0029] This application provides a refrigeration system, which includes a fan 101, a circulating condenser 102, a first condenser 103, a compressor 104, a filter 105, an electronic expansion valve 1, a four-way reversing valve 2, and a cold storage 106.

[0030] See Figure 1 The circulating condenser 102 is sequentially connected to the first condenser 103, the four-way reversing valve 2, the compressor 104, the air cooler 101, and the electronic expansion valve 1 to form an outer ring channel;

[0031] See Figure 2 The circulating condenser 102 is also connected in sequence to the cold storage 106 and the filter 105 to form an internal circulation air duct.

[0032] Specifically, see [link to relevant documentation] Figure 1 and Figure 2 In one embodiment, the circulating condenser 102 may include a first windshield S1, a second windshield S2, a third windshield S3, and a fourth windshield S4;

[0033] When the second windshield S2 and the fourth windshield S4 are closed, and the first windshield S1 and the third windshield S3 are open, the first channel of the circulating condenser 102 is closed, the circulating condenser 102 is disconnected from the cold storage 106 and the filter 105, and the internal circulation air duct is closed.

[0034] With the second windshield S2 and the fourth windshield S4 open, and the first windshield S1 and the third windshield S3 closed, the first channel of the circulating condenser 102 is opened, the circulating condenser 102 is connected to the cold storage 106 and the filter 105, and the internal circulation air duct is opened.

[0035] This embodiment proposes a refrigeration system that solves both the defrosting temperature rise and reduces the amount of secondary frost. The system employs a hot refrigerant defrosting method. The inlet and outlet of the circulating condenser 102 are connected to both the inner and outer loop channels. During system refrigeration operation, the inlet and outlet of the circulating condenser 102 are connected to the outer loop channel, functioning as a regular condenser and releasing heat through condensation. During defrosting operation, the inlet and outlet of the circulating condenser 102 are connected to the inner loop channel. The high-temperature, high-humidity steam generated in the cold storage 106 enters the inner loop channel, exchanges heat with the low-temperature refrigerant in the circulating condenser 102, and then returns to the cold storage 106. This inner loop channel can cool and dehumidify the high-temperature, high-humidity steam during the defrosting process. The cooled and dehumidified air is then reintroduced into the cold storage 106, completing the internal air circulation within the cold storage 106 and maintaining a constant storage temperature.

[0036] This application also provides a refrigeration system control method, applied to a refrigeration system including a cooler, a circulating condenser, a first condenser, a compressor, a filter, an electronic expansion valve, a four-way reversing valve, and a cold storage unit. The circulating condenser is sequentially connected to the first condenser, the four-way reversing valve, the compressor, the cooler, and the electronic expansion valve to form an outer loop channel. The circulating condenser is also sequentially connected to the cold storage unit and the filter to form an inner loop air duct. See also... Figure 3 The refrigeration system control method includes:

[0037] Step 301: When the refrigeration system is performing the refrigeration function, control the internal circulation duct to close;

[0038] Step 302: When the refrigeration system performs the defrosting function, control the internal circulation air duct to open.

[0039] Specifically, in one embodiment, the circulating condenser includes a first windshield, a second windshield, a third windshield, and a fourth windshield; the refrigeration system control method includes: when the refrigeration system performs a refrigeration function, controlling the second windshield and the fourth windshield to close, the first windshield and the third windshield to open, the first channel of the circulating condenser to close, the circulating condenser to disconnect from the cold storage and the filter, and the internal circulation duct to close; when the refrigeration system performs a defrosting function, controlling the second windshield and the fourth windshield to open, the first windshield and the third windshield to close, the first channel of the circulating condenser to open, the circulating condenser to establish a connection with the cold storage and the filter, and the internal circulation duct to open.

[0040] In practical applications, after the system switches to thermal defrosting mode, it can first determine whether the corresponding conditions have been met. If the corresponding conditions are met, the internal circulation duct is opened.

[0041] Specifically, in one embodiment, when the refrigeration system performs the defrosting function, controlling the internal circulation duct to open includes:

[0042] The average temperature and average humidity at each measuring point of the air cooler are detected.

[0043] Based on the average temperature and average humidity at each measuring point of the air cooler, determine whether to control the opening of the internal circulation duct.

[0044] In practical applications, the decision to open the internal circulation duct can be made based on the average temperature and average humidity at each measuring point of the air cooler, using the following method:

[0045] Determine whether the average temperature at each measuring point of the air cooler reaches a first temperature value and whether the average humidity at each measuring point of the air cooler reaches a first humidity value. If the average temperature at each measuring point of the air cooler reaches the first temperature value and the average humidity at each measuring point of the air cooler reaches the first humidity value, determine whether the outlet pipe temperature of the circulating condenser is higher than the average temperature at each measuring point of the air cooler. If the outlet pipe temperature of the circulating condenser is higher than the average temperature at each measuring point of the air cooler, control the opening of the internal circulation duct.

[0046] After the refrigeration system enters defrost mode, the average temperature Ta and average humidity Pa of each measuring point of the evaporative cooler are detected to determine whether they have reached the set values ​​T1+s and P1 (T1 and P1 are the average temperature and humidity during refrigeration operation). If not, the temperature and humidity are continuously monitored. If so, it is determined whether the outlet pipe temperature Tx of the circulating condenser is higher than the average temperature Ta of the measuring points near the evaporative cooler. If not, the temperature and humidity are continuously monitored. If so, the internal circulation duct is controlled to open.

[0047] In addition, in this embodiment, besides controlling whether the internal circulation duct is open, the temperature and air volume inside the internal circulation duct can also be controlled.

[0048] Specifically, in one embodiment, when the refrigeration system performs the defrosting function, the method further includes: detecting the supply air temperature of the internal circulation duct; determining the supply air temperature deviation based on the supply air temperature and a preset temperature setting value; reducing the supply air volume in the internal circulation duct when the supply air temperature deviation is greater than 0; increasing the supply air volume in the internal circulation duct when the supply air temperature deviation is less than 0; and not changing the supply air volume in the internal circulation duct when the supply air temperature deviation is equal to 0.

[0049] The process can be described as follows:

[0050] First, input and set the parameters as follows:

[0051] Internal circulation air supply temperature setpoint SH = Set temperature T1 - Air supply temperature difference setpoint X_EXV;

[0052] Supply air temperature deviation ek = Monitored supply air temperature SR - Internal circulation supply air temperature setpoint SH;

[0053] When entering the (K+1)th sampling period, the air volume of the variable frequency fan is controlled as follows:

[0054] Qk+1=Qk-ΔQk

[0055] ΔQk=Kd*ek (proportional coefficient Kd>0)

[0056] When the detected supply air temperature SR is higher than the internal circulation set supply air temperature SH, and the supply air temperature deviation ek > 0, the fan air volume decreases when entering the (K+1)th sampling cycle, thus lowering the supply air temperature SR. Conversely, when the detected supply air temperature SR is lower than the internal circulation set supply air temperature SH, and the supply air temperature deviation ek < 0, the fan air volume increases when entering the (K+1)th sampling cycle, thus raising the supply air temperature SR. When ek = 0, the evaporative cooler does not make any adjustments.

[0057] Furthermore, in one embodiment, when the refrigeration system performs the defrosting function, the method further includes:

[0058] The heat exchange temperature difference of the internal circulation air duct is detected, and the heat exchange temperature difference deviation is determined based on the heat exchange temperature difference and the preset heat exchange temperature difference setting value.

[0059] When the heat exchange temperature difference deviation is greater than 0, increase the opening of the electronic expansion valve to raise the evaporation temperature of the circulating condenser;

[0060] When the supply air temperature deviation is less than 0, the opening of the electronic expansion valve is reduced to lower the evaporation temperature of the circulating condenser.

[0061] The process can be described as follows:

[0062] First, input and set the parameters as follows:

[0063] The setpoint for the evaporator temperature of the circulating condenser is calculated as: SC = SR - E - EXV (detected supply air temperature).

[0064] Heat exchange temperature difference deviation eq = Detected heat exchange temperature difference SV - Heat exchange temperature difference setpoint E_EXV;

[0065] When entering the (K+1)th sampling period, the opening degree of the electronic expansion valve is controlled as follows:

[0066] Uk+1=Uk+ΔUk

[0067] ΔUk=Kd*eq (proportional coefficient Kd>0)

[0068] When the detected heat exchange temperature difference SV is higher than the set value E_EXV and the supply air temperature deviation eq > 0, the opening of the electronic expansion valve increases when entering the K+1 sampling cycle, increasing the evaporation temperature of the circulating condenser and decreasing the heat exchange temperature difference SV. Conversely, when the detected heat exchange temperature difference SV is lower than the set value E_EXV and the supply air temperature deviation eq < 0, the opening of the electronic expansion valve decreases when entering the K+1 sampling cycle, decreasing the evaporation temperature of the circulating condenser and increasing the heat exchange temperature difference SV. When eq = 0, no adjustment is made.

[0069] This embodiment uses a parallel adjustment mode of air cooler and electronic expansion valve to control the temperature difference between the evaporation temperature (pipe temperature of the circulating condenser) and the supply air temperature during the defrosting process to keep the supply air temperature stable.

[0070] The refrigeration system and control method provided in this application include a refrigeration system comprising a cooler, a circulating condenser, a first condenser, a compressor, a filter, an electronic expansion valve, a four-way reversing valve, and a cold storage unit. The circulating condenser is sequentially connected to the first condenser, the four-way reversing valve, the compressor, the cooler, and the electronic expansion valve to form an outer loop channel. The circulating condenser is also sequentially connected to the cold storage unit and the filter to form an inner loop air duct. When the refrigeration system performs its refrigeration function, the inner loop air duct is controlled to close; when the refrigeration system performs its defrosting function, the inner loop air duct is controlled to open. In this embodiment, the circulating condenser is connected to both the inner loop air duct and the outer loop. During system refrigeration operation, the circulating condenser is connected to the outer loop and participates in condensation and heat release as a regular condenser. During system defrosting operation, the circulating condenser is connected to the inner loop air duct, and high-temperature, high-humidity steam in the cold storage unit enters the inner loop air duct, exchanges heat with the low-temperature refrigerant in the circulating condenser, and then returns to the cold storage unit. This embodiment can cool and dehumidify the high-temperature and high-humidity steam during the defrosting process, and then send the cooled and dehumidified air back into the cold storage. This can avoid secondary frosting during the defrosting process, maintain a constant storage temperature during the defrosting process, recover the cold energy generated by the condenser during the defrosting process, and reduce the risk of the compressor operating with liquid.

[0071] The solution of this application will now be described in detail with reference to application examples.

[0072] This embodiment proposes a refrigeration system and self-regulating control method that solves both the defrosting temperature rise and reduces the amount of secondary frost. The system employs a hot refrigerant defrosting method and mainly includes a first condenser, a circulating condenser, and an indoor evaporator, with the first condenser connected in series with the circulating condenser. The inlet and outlet of the circulating condenser are connected to both the inner and outer loop channels. During system refrigeration operation, the inlet and outlet of the circulating condenser are connected to the outer loop channel, acting as a regular condenser for condensation and heat release. During defrosting operation, the inlet and outlet of the circulating condenser are connected to the inner loop channel. The high-temperature, high-humidity steam generated during defrosting enters the inner loop channel, exchanges heat with the low-temperature refrigerant in the circulating condenser, and then returns to the cold storage. This refrigeration system can cool and dehumidify the high-temperature, high-humidity steam generated during the defrosting process. The cooled and dehumidified air is then reintroduced into the cold storage, completing the internal air circulation and maintaining a constant storage temperature.

[0073] This embodiment can solve the following technical problems:

[0074] 1. The high-temperature and high-humidity steam after defrosting is prone to re-frostling when the system switches to refrigeration.

[0075] 2. Defrosting causes the temperature in the cold storage to rise, resulting in large temperature fluctuations inside the storage.

[0076] 3. Cold loss during defrosting.

[0077] The working process of the refrigeration system in this embodiment is as follows:

[0078] See Figure 1 and Figure 2 When the system is running in cooling mode, the refrigerant flow direction is 101 air cooler - 104 compressor - 103 first condenser - 102 circulating condenser - 1 electronic expansion valve - 101 air cooler. The second fan baffle S2 and the fourth fan baffle S4 are closed, and the first fan baffle S1 and the third fan baffle S3 are open and connected to the outdoor environment. The circulating condenser 102, as a regular condenser, participates in condensation heat exchange together with the first condenser 102. When the system switches to hot refrigerant defrosting mode, the refrigerant flow direction is: 101 air cooler - 1 electronic expansion valve - 102 circulating condenser - 103 first condenser - 104 compressor - 101 air cooler. When the corresponding conditions are met, the internal circulation system is activated, the first fan baffle S1 and the third fan baffle S3 are closed, and the second fan baffle S2 and the fourth fan baffle S4 are opened, forming a closed internal circulation air duct with the cold storage 106. Defrosting vapor from the high-temperature area of ​​the cold storage 106 enters the circulating condenser 102 through the air intakes F1 and F2 for cooling and dehumidification, and then returns to the cold storage 106 through the air outlet F3, reducing the temperature rise inside the storage. After defrosting, the system resumes refrigeration operation. When the corresponding conditions are met, the internal circulation system is closed, and the corresponding components operate according to logic, entering the next cycle.

[0079] The control methods for internal circulation systems include the following:

[0080] (a) The internal circulation system is activated:

[0081] See Figure 4 Step 1: After the unit enters defrosting mode, the average temperature Ta and average humidity Pa of each measuring point of the air cooler are detected to determine whether the set values ​​T1+s and P1 (T1 and P1 are the average temperature and humidity during cooling operation) are reached. If not, the temperature and humidity are continuously detected. If yes, proceed to step 2.

[0082] Step 2: Determine whether the outlet pipe temperature Tx of the circulating condenser is higher than the average temperature Ta of the measuring points near the air cooler. If not, continue to monitor the temperature and humidity. If so, start the internal circulation system of the unit.

[0083] (II) System self-regulation control method: The system adopts a parallel regulation mode of fan and expansion valve. The expansion valve is used to control the temperature difference between the evaporation temperature (pipe temperature of the circulating condenser) and the supply air temperature during the defrosting process to keep it constant, and the variable frequency fan is used to regulate the circulating air volume to maintain a stable supply air temperature.

[0084] (1) Variable frequency fan adjustment:

[0085] Input parameters and setting parameters:

[0086] Internal circulation air supply temperature setpoint SH = Set temperature T1 - Supply air temperature difference setpoint X - EXV; Supply air temperature deviation ek = Monitored supply air temperature SR - Internal circulation air supply temperature setpoint SH

[0087] When entering the (K+1)th sampling period, the air volume of the variable frequency fan is controlled as follows:

[0088] Qk+1=Qk-ΔQk

[0089] ΔQk=Kd*ek (proportional coefficient Kd>0)

[0090] When the detected supply air temperature SR is higher than the internal circulation set supply air temperature SH, and the supply air temperature deviation ek > 0, the fan air volume decreases when entering the (K+1)th sampling cycle, thus lowering the supply air temperature SR. Conversely, when the detected supply air temperature SR is lower than the internal circulation set supply air temperature SH, and the supply air temperature deviation ek < 0, the fan air volume increases when entering the (K+1)th sampling cycle, thus raising the supply air temperature SR. When ek = 0, the fan does not adjust.

[0091] (2) Electronic expansion valve adjustment:

[0092] Input parameters and setting parameters:

[0093] Circulating condenser evaporator temperature setpoint SC = Detected supply air temperature SR - Heat exchange temperature difference setpoint E_EXV

[0094] Heat exchange temperature difference deviation eq = Detected heat exchange temperature difference SV - Heat exchange temperature difference setpoint E_EXV

[0095] When entering the (K+1)th sampling period, the opening degree of the electronic expansion valve is controlled as follows:

[0096] Uk+1=Uk+ΔUk

[0097] ΔUk=Kd*eq (proportional coefficient Kd>0)

[0098] When the detected heat exchange temperature difference SV is higher than the set value E_EXV and the supply air temperature deviation eq > 0, the opening of the electronic expansion valve increases when entering the K+1 sampling cycle, increasing the evaporation temperature of the circulating condenser and decreasing the heat exchange temperature difference SV. Conversely, when the detected heat exchange temperature difference SV is lower than the set value E_EXV and the supply air temperature deviation eq < 0, the opening of the electronic expansion valve decreases when entering the K+1 sampling cycle, decreasing the evaporation temperature of the circulating condenser and increasing the heat exchange temperature difference SV. When eq = 0, no adjustment is made.

[0099] During defrosting, the electronic expansion valve and fan speed are adjusted once every [T_EXV] seconds of the supply air temperature sampling period. The controller detects the supply air temperature deviation (detected supply air temperature value and set supply air temperature value) and heat exchange temperature difference (heat exchange temperature difference - heat exchange temperature difference set value) of the system every [T_EXV] seconds. Both components are adjusted by detecting the supply air temperature. The final adjustment result is that the actual temperature difference between the evaporation temperature of the circulating condenser and the supply air temperature reaches the set value E_EXV, and the temperature difference between the supply air temperature and the storage temperature reaches the set value X_EXV.

[0100] (III) Internal circulation system shutdown: When the unit exits defrosting mode, the internal circulation system is shut down.

[0101] The inventive point of this embodiment:

[0102] 1. During the defrosting process, the circulating air of the cold storage passes through the circulating condenser to recover the cold energy generated by the condenser during the defrosting process, thereby achieving the purpose of cooling and dehumidification.

[0103] 2. The internal circulation system of the cold storage can process the high temperature and high humidity steam generated during defrosting into low temperature and low humidity air, which not only ensures the constant temperature of the storage during the defrosting process, but also reduces the amount of secondary frost after defrosting.

[0104] 3. By using the first condenser in series with the circulating condenser, the risk of incomplete refrigerant evaporation and compressor operation with liquid during defrosting is reduced, thus improving the stability of the refrigeration system.

[0105] The beneficial effects of this embodiment:

[0106] 1. Due to the adoption of the refrigeration system and internal circulation method of the present invention, the defrosting temperature rise can be effectively reduced, and the temperature fluctuation of the storage room before and after the defrosting process is small.

[0107] 2. Due to the adoption of the refrigeration system and internal circulation method of the present invention, defrosting vapor can be discharged in a timely manner, reducing the amount of secondary frosting and increasing the operating efficiency of the unit.

[0108] 3. Because a circulating condenser is added to the refrigeration system, the system can recover some of the cold energy generated by the condenser during the defrosting process, which can reduce energy loss.

[0109] This application also provides an electrical device, which includes the refrigeration system described in any of the above embodiments. Furthermore, see... Figure 5 The electrical device may further include a processor 111, a communication interface 112, a memory 113, and a communication bus 114, wherein the processor 111, the communication interface 112, and the memory 113 communicate with each other through the communication bus 114.

[0110] Memory 113 is used to store computer programs;

[0111] In one embodiment of this application, the processor 111, when executing a program stored in the memory 113, implements the control method provided in any of the foregoing method embodiments.

[0112] This application also provides a storage medium storing a computer program, which, when executed by a processor, implements the steps of any of the methods described above.

[0113] The device embodiments described above are merely illustrative. The units described as separate components may or may not be physically separate. 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.

[0114] 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.

[0115] 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.

[0116] The above description is merely a specific embodiment of the present invention, enabling those skilled in the art to understand or implement the invention. 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 the invention. Therefore, the present invention 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 method for controlling a refrigeration system, characterized in that, This is applied to a refrigeration system, which includes a cooler, a circulating condenser, a first condenser, a compressor, a filter, an electronic expansion valve, a four-way reversing valve, and a cold storage; the circulating condenser is sequentially connected to the first condenser, the four-way reversing valve, the compressor, the cooler, and the electronic expansion valve to form an outer loop channel; The circulating condenser is also connected in sequence to the cold storage and the filter to form an internal circulating air duct; The refrigeration system control method includes: When the refrigeration system performs its refrigeration function, the internal circulation duct is controlled to close. The circulating condenser includes a first damper, a second damper, a third damper, and a fourth damper. The refrigeration system control method includes: when the refrigeration system performs its refrigeration function, controlling the second damper and the fourth damper to close, the first damper and the third damper to open, the first channel of the circulating condenser to close, the circulating condenser to disconnect from the cold storage and the filter, and the internal circulation duct to close. When the refrigeration system performs the defrosting function, the internal circulation air duct is opened.

2. The refrigeration system control method according to claim 1, characterized in that, When the refrigeration system performs the defrosting function, the second and fourth fan dampers are opened, the first and third fan dampers are closed, the first channel of the circulating condenser is opened, the circulating condenser is connected to the cold storage and the filter, and the internal circulation air duct is opened.

3. The refrigeration system control method according to claim 1, characterized in that, When the refrigeration system performs the defrosting function, controlling the opening of the internal circulation duct includes: The average temperature and average humidity at each measuring point of the air cooler are detected. Based on the average temperature and average humidity at each measuring point of the air cooler, determine whether to control the opening of the internal circulation duct.

4. The refrigeration system control method according to claim 3, characterized in that, The step of determining whether to open the internal circulation duct based on the average temperature and average humidity at each measuring point of the air cooler includes: Determine whether the average temperature at each measuring point of the air cooler reaches a first temperature value, and whether the average humidity at each measuring point of the air cooler reaches a first humidity value. If the average temperature at each measuring point of the air cooler reaches a first temperature value and the average humidity at each measuring point of the air cooler reaches a first humidity value, determine whether the outlet pipe temperature of the circulating condenser is higher than the average temperature at each measuring point of the air cooler. When the outlet pipe temperature of the circulating condenser is higher than the average temperature of each measuring point of the air cooler, the internal circulation duct is opened.

5. The refrigeration system control method according to claim 1, characterized in that, When the refrigeration system performs the defrosting function, the method further includes: The air supply temperature of the internal circulation duct is detected, and the air supply temperature deviation is determined based on the air supply temperature and the preset temperature setting value. If the supply air temperature deviation is greater than 0, reduce the supply air volume in the internal circulation duct. When the air supply temperature deviation is less than 0, increase the air supply volume in the internal circulation duct.

6. The refrigeration system control method according to claim 1, characterized in that, When the refrigeration system performs the defrosting function, the method further includes: The heat exchange temperature difference of the internal circulation air duct is detected, and the heat exchange temperature difference deviation is determined based on the heat exchange temperature difference and the preset heat exchange temperature difference setting value. When the heat exchange temperature difference deviation is greater than 0, the opening of the electronic expansion valve is increased to raise the evaporation temperature of the circulating condenser; When the heat exchange temperature difference deviation is less than 0, the opening of the electronic expansion valve is reduced to lower the evaporation temperature of the circulating condenser.

7. A refrigeration system, characterized in that, The refrigeration system includes a fan cooler, a circulating condenser, a first condenser, a compressor, a filter, an electronic expansion valve, a four-way reversing valve, and a cold storage unit. The circulating condenser is sequentially connected to the first condenser, the four-way reversing valve, the compressor, the air cooler, and the electronic expansion valve to form an outer loop channel; The circulating condenser is also connected in sequence to the cold storage and the filter to form an internal circulating air duct; The circulating condenser can control the internal circulation duct to close when the refrigeration system is performing the refrigeration function; and control the internal circulation duct to open when the refrigeration system is performing the defrosting function. The circulating condenser includes a first windshield, a second windshield, a third windshield, and a fourth windshield. When the second windshield and the fourth windshield are closed, and the first windshield and the third windshield are open, the first channel of the circulating condenser is closed, the circulating condenser is disconnected from the cold storage and the filter, and the internal circulation duct is closed.

8. The refrigeration system according to claim 7, characterized in that, With the second and fourth windshields open and the first and third windshields closed, the first channel of the circulating condenser opens, the circulating condenser is connected to the cold storage and the filter, and the internal circulation duct opens.

9. An electrical appliance, characterized in that, The electrical equipment includes the refrigeration system as described in any one of claims 7-8.

10. A storage medium storing a computer program, characterized in that, When the computer program is executed by a processor, it implements the steps of the method according to any one of claims 1 to 6.

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