Refrigerator and defrosting control method thereof

Abstract

According to the refrigerator and the defrosting control method thereof, a gas storage tank capable of adjusting the amount of a refrigerant is introduced into a hot gas bypass defrosting technology, then an inflation branch, a deflation branch and a defrosting branch which are independent of a refrigeration circulation loop are formed, and through the arrangement of the gas storage tank and the cooperation of the inflation branch and the deflation branch, the defrosting control of the refrigerator is achieved. The quantity of refrigerants in the refrigerating system can be flexibly adjusted, optimization of the flow and distribution of the refrigerants is achieved by controlling the conduction state of the first electromagnetic valve and the second electromagnetic valve in different operation modes, improvement of the overall performance and efficiency of the refrigerating system is facilitated, meanwhile, an independent defrosting branch is further designed, the defrosting process is optimized, and the defrosting efficiency is improved. And the overall performance and the energy-saving effect of the refrigerator are improved. Besides, according to the comparison result of the defrosting heat and the preset heat threshold value, it is determined that the system operates in the inflation mode or the deflation mode or the bypass defrosting mode, the optimal operation mode can be flexibly selected according to different defrosting heat requirements, and the refrigerating system can meet the defrosting requirements more efficiently.

Description

Technical Field

[0001] The present invention relates to the technical field of refrigerators, and in particular to a refrigerator and a defrosting control method thereof. Background Art

[0002] Air-cooled frost-free refrigerators are popular among users due to their large capacity, automatic defrosting, and multiple compartment functions. However, the most commonly used defrosting method is electric heating defrosting, which consumes a lot of power, has a single defrosting heat source, occupies a large compartment space, and has safety hazards due to the high heater temperature during defrosting. These have restricted the development of air-cooled frost-free refrigerators to a certain extent. In order to solve this problem, the existing technology also adopts a hot gas bypass defrosting method, which can eliminate the power consumption generated by traditional electric heating defrosting, save energy, and not occupy compartment space. Figure 1 This is a schematic diagram of the principle of the hot gas bypass defrosting system established on the refrigeration system adopted in the prior art. When the defrosting system is running, the connection end of the solenoid valve and the condenser is closed, and the connection end of the solenoid valve and the evaporator is opened. The high-temperature and high-pressure exhaust gas of the compressor flows into the evaporator through the solenoid valve, dissipates heat to the frost layer of the evaporator, melts the frost layer, and the refrigerant gas dissipates heat to the external environment, the temperature becomes lower, and then flows back to the compressor to inhale, completing a hot gas bypass defrosting cycle. Although the traditional hot gas bypass defrosting can complete the defrosting, the refrigerant flow rate is fixed during the hot gas bypass defrosting process, and the refrigerant flow rate in the system cannot be adjusted as needed according to the defrosting requirements, resulting in low defrosting efficiency. Summary of the invention

[0003] The purpose of the embodiment of the present invention is to provide a refrigerator and a defrost control method thereof. By introducing a refrigerant gas storage tank and a refrigerant flow regulating valve into the system, and by setting a gas storage tank and reasonable pipeline connection and solenoid valve control, the amount of refrigerant in the refrigeration system can be flexibly adjusted. At the same time, an independent defrost branch is designed to optimize the defrost process and improve the overall performance and energy-saving effect of the refrigerator.

[0004] To achieve the above object, an embodiment of the present invention provides a refrigerator, comprising:

[0005] a box body, in which at least one storage chamber is formed, and the storage chamber includes at least a refrigerating chamber;

[0006] A refrigeration system, used to provide coldness for the refrigerator, the refrigeration system comprising a compressor, a condenser and an evaporator connected in sequence through pipelines;

[0007] An air storage tank, used to reduce or increase the amount of refrigerant in the refrigeration system, comprises an air inlet and an air outlet, wherein the air inlet is connected to the pipe between the compressor and the condenser via a first solenoid valve to form an air charging branch of the air storage tank; the air outlet is connected to the pipe between the evaporator and the condenser via a second solenoid valve to form an air discharging branch of the air storage tank; wherein a defrost branch independent of the air storage tank is also formed between the first solenoid valve and the second solenoid valve.

[0008] The above technical solution has the following advantages or beneficial effects: the setting of the gas storage tank and the coordination of the gas charging branch and the gas discharging branch can flexibly adjust the amount of refrigerant in the refrigeration system. In different operating modes, by controlling the conduction state of the first and second solenoid valves, the refrigerant flow and distribution are optimized, which helps to improve the overall performance and efficiency of the refrigeration system. At the same time, an independent defrosting branch is designed to optimize the defrosting process and improve the overall performance and energy saving effect of the refrigerator.

[0009] In some embodiments of the present application, the refrigerator further comprises:

[0010] A controller, the controller being configured to:

[0011] When it is detected that the refrigerator meets the defrosting conditions and no frost blockage occurs, the defrosting heat required by the refrigerator to complete the current defrosting is calculated;

[0012] The defrosting heat is compared with a preset heat threshold, and a corresponding operation mode is determined according to the comparison result; wherein the operation mode includes an inflation mode in which the inflation branch is turned on, an deflation mode in which the deflation branch is turned on, and a bypass defrosting mode in which the bypass branch is turned on;

[0013] The valve port conduction states of the first solenoid valve and the second solenoid valve are adjusted according to the operation mode.

[0014] The above technical solution has the following advantages or beneficial effects: by detecting whether the refrigerator meets the defrosting conditions and no frost blockage occurs, and calculating the defrosting heat required to complete this defrosting, it can accurately provide heat for the defrosting process according to the actual defrosting needs, and will neither cause incomplete defrosting due to insufficient heat nor cause energy waste due to excessive heat. In addition, based on the comparison result between the defrosting heat and the preset heat threshold, it is determined that the system is operating in the inflation mode, deflation mode or bypass defrosting mode, and the best operating mode can be flexibly selected according to different defrosting heat requirements, so that the refrigeration system can meet the defrosting requirements more efficiently. The frost blockage factor is considered in the defrosting control logic to avoid defrosting operations when frost blockage may occur, thereby effectively preventing frost blockage problems caused by improper defrosting and ensuring the stable operation of the refrigeration system.

[0015] In some embodiments of the present application, the inflation mode includes a first inflation mode and a second inflation mode, and the refrigerant inflation amount of the first inflation mode is smaller than the refrigerant inflation amount of the second inflation mode; the deflation mode includes a first deflation mode and a second deflation mode, and the refrigerant deflation amount of the first deflation mode is smaller than the refrigerant deflation amount of the second deflation mode.

[0016] The above technical solution has the following advantages or beneficial effects: different defrosting conditions have different heat requirements. By setting the first inflation mode, the second inflation mode, the first deflation mode, and the second deflation mode, the inflation amount or deflation amount of the refrigerant can be adjusted more accurately according to the comparison result between the calculated defrosting heat and the preset heat threshold, so as to accurately match the heat required in the defrosting process and achieve a more efficient and precise defrosting operation. In addition, precise control of the inflation amount and deflation amount of the refrigerant helps to maintain the pressure balance inside the refrigeration system. During the defrosting process, it avoids large fluctuations in system pressure due to improper refrigerant inflation and deflation, thereby reducing damage to key components such as the compressor and extending the service life of the refrigeration system.

[0017] In some embodiments of the present application, determining the corresponding operation mode according to the comparison result includes:

[0018] When the defrosting heat is greater than or equal to a preset maximum heat threshold, determining that the operation mode is to enter the second air release mode and the bypass defrosting mode in sequence;

[0019] When the defrost heat is less than the maximum heat threshold and greater than or equal to the preset minimum heat threshold, determining that the operation mode is to sequentially enter the first deflation mode and the bypass defrost mode, or determining that the operation mode is to sequentially enter the first inflation mode and the bypass defrost mode;

[0020] When the defrost heat is less than the minimum heat threshold, the operation mode is determined to be the bypass defrost mode, or the operation mode is determined to enter the second charging mode and the bypass defrost mode in sequence.

[0021] The above technical solution has the following advantages or beneficial effects: by setting the maximum heat threshold and the minimum heat threshold, the defrosting heat demand is divided into different intervals, and a corresponding operating mode is formulated for each interval. This precise matching avoids the problem of excessive or insufficient defrosting that may occur when a unified mode is used to deal with different defrosting conditions, thereby improving the defrosting efficiency and effect. In addition, the reasonable selection of the refrigerant charging and discharging mode avoids the additional pressure and wear on the compressor, solenoid valve and other components caused by excessive charging and discharging of the refrigerant. And the ability to flexibly adjust the operating mode according to different defrosting heat requirements enables the refrigeration system to maintain good defrosting performance and refrigeration effect under various complex working conditions, thereby enhancing the adaptability and flexibility of the system.

[0022] In some embodiments of the present application, after comparing the defrost heat with a preset heat threshold, the controller is further configured to:

[0023] The gear position of the compressor is adjusted according to the comparison result.

[0024] The above technical solution has the following advantages or beneficial effects: different defrost heat requirements mean different difficulties of the defrost task. By comparing the defrost heat with the preset threshold and adjusting the compressor gear accordingly, the energy that matches the defrost process can be accurately provided.

[0025] In some embodiments of the present application, adjusting the gear position of the compressor according to the comparison result includes:

[0026] When the defrosting heat is greater than or equal to a preset maximum heat threshold, controlling the gear position of the compressor to the first gear position;

[0027] When the defrosting heat is less than the maximum heat threshold and greater than or equal to the preset minimum heat threshold, controlling the gear position of the compressor to the second gear position or the third gear position;

[0028] When the defrost heat is less than the minimum heat threshold, the gear of the compressor is controlled to be the third gear; the rotation speed of the first gear is greater than the rotation speed of the second gear, and the rotation speed of the second gear is greater than the rotation speed of the third gear.

[0029] The above technical solution has the following advantages or beneficial effects: by finely adjusting the compressor gear according to the defrosting heat, accurate energy distribution is achieved, so that the compressor runs at the most appropriate speed under different defrosting requirements, only providing the energy required to meet the defrosting, avoiding energy waste caused by high-load operation, effectively improving energy utilization efficiency, reducing the overall energy consumption of the refrigerator, and complying with the concept of energy conservation and environmental protection. In addition, the compressor is adjusted to a suitable speed gear according to actual needs in different defrosting scenarios, avoiding long-term high-load operation. High-speed operation will cause the compressor to bear greater pressure and wear. By reasonably reducing the speed, the friction and loss of the internal components of the compressor are reduced, the service life of the compressor is extended, and the maintenance cost and replacement frequency of the equipment are reduced.

[0030] In some embodiments of the present application, the calculating of the defrost heat required by the refrigerator to complete the current defrosting includes:

[0031] If the defrost heat is calculated for the first time in this defrost cycle, the defrost heat is calculated based on the mass, average temperature and flow rate of the refrigerant and the suction temperature and exhaust temperature of the compressor;

[0032] If the defrost heat is not calculated for the first time in this defrost cycle, the defrost heat is calculated according to the flow rate of the refrigerant and the suction temperature and exhaust temperature of the compressor.

[0033] The above technical solution has the following advantages or beneficial effects: accurate calculation of defrost heat helps the system to accurately allocate energy for the defrost process. After the defrost heat is determined by the first calculation, the system can select the appropriate operating mode and compressor gear accordingly to avoid waste due to excessive energy allocation or incomplete defrosting due to insufficient energy; flexible adjustment during non-first calculations allows the system to dynamically adapt to changes during the defrost process and continuously maintain an efficient defrost state, thereby improving the operating efficiency of the entire refrigeration system. In addition, by calculating the defrost heat in stages and in a targeted manner, it avoids the use of complex multi-parameter calculation methods throughout the entire defrost cycle, reducing unnecessary computing resource consumption and system response time, which enables the system to adjust the operating state more quickly according to the defrost heat, improve the system's real-time response capability, and ensure efficient and stable operation of the refrigeration system.

[0034] In some embodiments of the present application, the refrigerator further comprises:

[0035] A heater, disposed at the air intake port of the compressor, for increasing the air intake temperature of the compressor;

[0036] When the defrosting heat is greater than or equal to a preset maximum heat threshold, the controller is further configured to:

[0037] A target power of the heater is determined, and the heater is controlled to operate according to the target power.

[0038] The above technical solution has the following advantages or beneficial effects: when the defrosting heat provided by the compressor is insufficient, the heat provided by the compensating electric heater is used to provide heat other than the compressor exhaust for hot gas bypass defrosting, thereby preventing the compressor from "liquid hammer". In addition, the heater works in coordination with other components of the refrigeration system to dynamically adjust the power according to the heat difference, making the thermal management of the entire system during the defrosting process more reasonable. This collaborative optimization helps various parts of the system better adapt to different defrosting conditions, enhances the system's ability to cope with complex situations, and improves overall operating performance.

[0039] In some embodiments of the present application, determining the target power of the heater includes:

[0040] calculating a heat difference between the defrost heat and the maximum heat threshold;

[0041] The target power of the heater is determined according to the heat difference; wherein the target power is proportional to the heat difference.

[0042] The above technical solution has the following advantages or beneficial effects: it can accurately determine the additional heat that the heater needs to provide. This precise heat supplement mechanism enables the system to provide an appropriate amount of additional heat only when needed, thereby optimizing energy utilization efficiency.

[0043] To achieve the above-mentioned purpose, an embodiment of the present invention further provides a defrosting control method for a refrigerator, the refrigerator comprising a gas storage tank and a compressor, a condenser and an evaporator connected in sequence through pipelines; wherein the gas storage tank is connected to the pipeline between the compressor and the condenser through a first solenoid valve to form a gas branch; and is connected to the pipeline between the evaporator and the condenser through a second solenoid valve to form a defrosting branch; a defrosting branch is also formed between the first solenoid valve and the second solenoid valve; the method comprises:

[0044] When it is detected that the refrigerator meets the defrosting conditions and no frost blockage occurs, the defrosting heat required by the refrigerator to complete the current defrosting is calculated;

[0045] The defrosting heat is compared with a preset heat threshold, and a corresponding operation mode is determined according to the comparison result; wherein the operation mode includes an inflation mode in which the inflation branch is turned on, an deflation mode in which the deflation branch is turned on, and a bypass defrosting mode in which the bypass branch is turned on;

[0046] The valve port conduction states of the first solenoid valve and the second solenoid valve are adjusted according to the operation mode.

[0047] The above technical solution has the following advantages or beneficial effects: by detecting whether the refrigerator meets the defrosting conditions and no frost blockage occurs, and calculating the defrosting heat required to complete this defrosting, heat can be accurately provided for the defrosting process according to the actual defrosting requirements, and neither incomplete defrosting due to insufficient heat nor energy waste due to excessive heat. In addition, according to the comparison result of the defrosting heat and the preset heat threshold, it is determined that the system is operating in the inflation mode, the deflation mode or the bypass defrosting mode, and the best operation mode can be flexibly selected according to different defrosting heat requirements, so that the refrigeration system can meet the defrosting requirements more efficiently. The setting of the gas storage tank and the coordination of the inflation branch and the deflation branch can flexibly adjust the amount of refrigerant in the refrigeration system. Under different operation modes, by controlling the conduction state of the first and second solenoid valves, the refrigerant flow and distribution are optimized, which helps to improve the overall performance and efficiency of the refrigeration system. The frost blockage factor is considered in the defrosting control logic to avoid defrosting operations when frost blockage may occur, thereby effectively preventing frost blockage problems caused by improper defrosting and ensuring the stable operation of the refrigeration system. BRIEF DESCRIPTION OF THE DRAWINGS

[0048] Figure 1 It is a schematic diagram of the principle of a hot gas bypass defrosting system established on a refrigeration system adopted in the prior art;

[0049] Figure 2 is a schematic diagram of the external structure of a refrigerator provided by an embodiment of the present invention;

[0050] Figure 3 is a schematic diagram of the internal structure of a refrigerator provided by an embodiment of the present invention;

[0051] Figure 4 is a schematic diagram of a hot gas bypass defrosting system established on a refrigeration system provided by an embodiment of the present invention;

[0052] Figure 5 is another schematic diagram of a hot gas bypass defrosting system established on a refrigeration system provided by an embodiment of the present invention;

[0053] Figure 6 is a schematic diagram of the flow direction of the refrigerant in the first operating mode provided by an embodiment of the present invention;

[0054] Figure 7 is a schematic diagram of the flow direction of the refrigerant in the second operating mode provided by an embodiment of the present invention;

[0055] Figure 8 is a schematic diagram of the flow direction of the refrigerant in the fourth operation mode provided by an embodiment of the present invention;

[0056] Fig. 9 is a schematic diagram of the flow direction of the refrigerant in the sixth operation mode provided by an embodiment of the present invention;

[0057] Fig.10 is a first working flow diagram of a controller provided by an embodiment of the present invention;

[0058] Fig.11 is a second working flow diagram of the controller provided by an embodiment of the present invention;

[0059] Fig.12 The present invention is a flowchart of a refrigerator defrosting control method provided by an embodiment of the present invention. DETAILED DESCRIPTION

[0060] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0061] In the description of the present application, it should be understood that the terms "center", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", etc., indicating orientations or positional relationships, are based on the orientations or positional relationships shown in the accompanying drawings and are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present application.

[0062] The terms "first", "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of the features. In the description of this application, unless otherwise specified, "plurality" means two or more.

[0063] In the description of this application, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be an indirect connection through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0064] See also Figure 2 , Figure 2 It is a schematic diagram of the external structure of a refrigerator 100 provided by an embodiment of the present invention. The refrigerator 100 of this embodiment is approximately rectangular in shape. The refrigerator includes a box body that defines a storage space and one or more door bodies arranged at the opening of the box body, wherein the door body includes a door body shell located outside the box body, a door body liner located inside the box body, an upper end cover, a lower end cover, and an insulation layer located between the door body shell, the door body liner, the upper end cover, and the lower end cover; usually, the insulation layer is filled with foam. The box body is provided with a chamber, wherein the chamber includes a component storage chamber for placing components in the refrigerator, such as a press cabin, etc., and also includes a storage space for storing food, etc.

[0065] See also Figure 3 , Figure 3 1 is a schematic diagram of the internal structure of a refrigerator provided by an embodiment of the present invention. The storage space can be divided into multiple storage rooms. The storage rooms can be configured as a refrigerating room 101 and a freezing room 102 according to different uses. They can also include a temperature-changing room, a vacuum drawer, a moisturizing drawer, etc. Each storage room corresponds to one or more door bodies, for example, Figure 3The storage room at the upper part is provided with a double-opening door body. The door body can be pivotally arranged at the opening of the box body, and can also be opened in a drawer-like manner to realize drawer-like storage.

[0066] See also Figure 4 , Figure 4 Schematic diagram of a hot gas bypass defrosting system provided in an embodiment of the present invention, wherein the refrigeration system comprises a compressor 1, an evaporator 2, a capillary tube 3, a filter drier 4, a condenser 5, an air storage tank 6, a first solenoid valve 7, a second solenoid valve 8 and a heater 9 (which may also be omitted), and the refrigeration cycle is: compressor 1 → condenser 5 → filter drier 4 → capillary tube 3 → evaporator 2 → compressor 1, at which time an air storage tank 6 is connected to the refrigeration cycle, and the air storage tank 6 is used to reduce or increase the amount of refrigerant in the refrigeration system, and comprises an air inlet 6a and an air outlet 6b, and the air inlet 6a is connected to the first solenoid valve 7 through the second solenoid valve 8. The pipeline between the compressor 1 and the condenser 5 forms an air charging branch of the gas tank 6, and the air charging branch is used to charge the gas tank 6, that is, the amount of refrigerant in the system needs to be reduced at this time; the air outlet 6b is connected to the pipeline between the evaporator 2 and the condenser 5 (actually the pipeline between the evaporator 2 and the capillary tube 3) through the second solenoid valve 8, forming an air discharge branch of the gas tank 6, and the air discharge branch is used to discharge the gas tank 6, that is, the amount of refrigerant in the system needs to be increased at this time; wherein, a defrost branch independent of the gas tank is also formed between the first solenoid valve 7 and the second solenoid valve 8.

[0067] It should be noted that the number of the condensers can be multiple, such as 2 condensers, see Figure 5 , Figure 5 This is another schematic diagram of a hot gas bypass defrosting system established on a refrigeration system provided by an embodiment of the present invention, which includes a first condenser 51 and a second condenser 52. The first condenser 51 and the second condenser 52 are connected in series and connected to the refrigeration system. A large amount of heat is generated when the refrigerator is running, which needs to be dissipated in time to ensure the normal operation of the refrigeration system. The two condensers can share the heat dissipation task and dissipate the heat to the surrounding environment through different condensers. Compared with a single condenser, more heat can be dissipated in the same time, effectively improving the heat dissipation efficiency and ensuring the stability of the temperature inside the refrigerator.

[0068] Furthermore, in view of the different access modes of the gas storage tank 6, the embodiment of this solution includes the following 6 operating modes:

[0069] 1) Operation mode 1, i.e., refrigeration mode, at this time, the air inlet 6a of the first solenoid valve 7 connected to the air storage tank 6 and the valve port connected to the second solenoid valve 8 are closed, the valve port of the first solenoid valve 7 connected to the condenser 5 and the compressor 1 is opened, the air outlet 6b of the second solenoid valve 8 connected to the air storage tank 6 and the valve port connected to the first solenoid valve 7 are closed, and the valve port of the second solenoid valve 8 connected to the capillary tube 3 and the evaporator 2 is opened.

[0070] For example, see Figure 6 , Figure 6 It is a schematic diagram of the flow direction of the refrigerant provided by an embodiment of the present invention in the first operating mode. The dotted line represents the unconnected branch, and the solid line represents the connected branch. At this time, the charging branch, the exhaust branch and the defrosting branch are all unconnected. After the high-temperature and high-pressure exhaust gas of the compressor 1 passes through the condenser 5, it dissipates heat to the external environment and becomes a high-pressure and low-temperature refrigerant liquid. It flows through the drying filter 4 and the capillary tube 3 to become a low-pressure and low-temperature refrigerant liquid. After the refrigerant liquid flows into the evaporator 2, it absorbs the heat in the refrigerator storage compartment and becomes a low-pressure refrigerant gas, and then flows back to the compressor 1 through the return air pipe to complete a refrigeration cycle.

[0071] 2) Operation mode 2, i.e., the first deflation mode (one of the deflation modes mentioned below), the deflation amount of refrigerant in the first deflation mode is less than the deflation amount of refrigerant in the second deflation mode. At this time, the first solenoid valve 7 connected to the air inlet 6a of the air storage tank 6 and the valve port connected to the second solenoid valve 8 are closed, the valve port of the first solenoid valve 7 connected to the condenser 5 and the compressor 1 is opened, the valve port of the second solenoid valve 8 connected to the air outlet 6b of the air storage tank 6 is opened, the valve port of the second solenoid valve 8 connected to the first solenoid valve 7 is closed, and the valve port of the second solenoid valve 8 connected to the capillary tube 3 and the evaporator 2 is opened.

[0072] For example, see Figure 7 , Figure 7 It is a schematic diagram of the flow direction of the refrigerant provided by the embodiment of the present invention in the second operating mode. At this time, the charging branch and the defrosting branch are closed, and the deflation branch is connected. The gas storage tank 6 will gradually increase the amount of refrigerant in the system. Since the pressure in the gas storage tank 6 is higher than the pressure on the low-pressure side of the system (i.e., the inlet of the evaporator 2), the refrigerant enters the evaporator 2 from the gas storage tank 6. The quality of the refrigerant charged into the system in this process can be controlled by monitoring the pressure and temperature of the gas storage tank 6. When the system is charged, the second solenoid valve 8 and the valve port connection end of the gas outlet 6b of the gas storage tank 6 are closed instantly. This mode is operated when the heat required for defrosting the refrigerator is large.

[0073] 3) Operation mode 3, namely the second deflation mode (one of the deflation modes mentioned later), at this time, the valve opening / closing mode of the first solenoid valve 7 and the second solenoid valve 8 can refer to the first deflation mode.

[0074] For example, see Figure 7 At this time, the refrigerant in the gas tank 6 needs to be fully charged into the system. Since the pressure in the gas tank is higher than the pressure on the low-pressure side of the system (i.e., the evaporator inlet), the refrigerant enters the refrigeration system from the gas tank 6. When the pressure of the gas tank 6 is balanced with the pressure at the inlet of the evaporator 2 (it can be judged by measuring the pressure or flow at the inlet of the gas tank 6 and the evaporator 2. When the pressure of the pressure sensor is approximately equal, or the value of the flow sensor is small, it can be judged as balanced), the second solenoid valve 8 and the valve port connection end of the gas outlet 6b of the gas tank 6 are closed. At this time, it is considered that the refrigerant filling amount in the system has reached the maximum (the gas discharge amount of the gas tank 6 has also reached the maximum), and the hot gas bypass defrosting capacity is the strongest. This mode operates when the defrosting heat required by the refrigerator is ≥ the maximum defrosting heat that can be provided under the design conditions.

[0075] It should be noted that there is a maximum limit on the amount of refrigerant filled in the defrost system. At the maximum, it is necessary to ensure that the compressor can complete normal refrigerant compression, that is, when there is no "liquid hammer" at the suction temperature, the compressor's current, power, temperature and other parameters are within the compressor design range.

[0076] 4) Operation mode 4, i.e., the first charging mode (one of the charging modes mentioned below), the refrigerant charging amount of the first charging mode is less than the refrigerant charging amount of the second charging mode. At this time, the valve port of the first solenoid valve 7 connected to the air inlet 6a of the air storage tank 6 is opened, the valve port of the first solenoid valve 7 connected to the second solenoid valve 8 is closed, the valve port of the first solenoid valve 7 connected to the condenser 5 and the compressor 1 is opened, the valve port of the second solenoid valve 8 connected to the air outlet 6b of the air storage tank 6 is opened, the valve port of the second solenoid valve 8 connected to the first solenoid valve 7 is closed, and the valve port of the second solenoid valve 8 connected to the capillary tube 3 and the evaporator 2 is opened.

[0077] For example, see FIG. 8 . Figure 8It is a schematic diagram of the flow direction of the refrigerant in the fourth operation mode provided by the embodiment of the present invention. At this time, the deflation branch and the defrost branch are closed, and the charging branch is connected. The gas storage tank 6 will gradually recover the amount of refrigerant in the system. During this process, the compressor 1 does not stop and the system is evacuated. Since the pressure in the gas storage tank 6 is lower than the pressure on the high-pressure side of the system (i.e., the exhaust side of the compressor 1), the refrigerant enters the gas storage tank 6 from the refrigeration system. The quality of the refrigerant charged into the gas storage tank 6 during this process is controlled by monitoring the pressure and temperature of the gas storage tank 6. When the gas storage tank 6 is charged, the valve port connection end between the first solenoid valve 7 and the air inlet 6a of the gas storage tank 6 is closed instantly. This mode is operated when the heat required for defrosting the refrigerator is reduced.

[0078] 5) Operation mode 5, i.e., the second inflation mode (one of the inflation modes mentioned later), at this time, the valve opening / closing mode of the first solenoid valve 7 and the second solenoid valve 8 can refer to the first inflation mode.

[0079] For example, see Figure 8 When it is necessary to discharge all the relatively redundant refrigerant in the system from the refrigeration system, the charging branch is connected, and the gas storage tank 6 starts to charge to recover the amount of refrigerant in the refrigeration system. When the mass of the refrigerant charged into the gas storage tank 6 reaches the maximum value, and the mass of the refrigerant in the refrigeration system reaches the set value to ensure the designed refrigeration capacity of the refrigeration system, the valve port connection end between the first solenoid valve 7 and the air inlet 6a of the gas storage tank 6 is closed. At this time, it is considered that the amount of refrigerant charged in the system has reached the minimum (the amount of gas charged in the gas storage tank 6 has reached the maximum), and the hot gas bypass defrosting capacity is the weakest. This mode operates when the defrosting heat required by the refrigerator is ≤ the minimum defrosting heat that can be provided under the design conditions. At this time, the mass of the refrigerant in the refrigeration system is equal to the mass of the refrigerator under the design conditions, and the refrigerant that can be used for hot gas bypass defrosting is the least.

[0080] 6) Operation mode 6, i.e., bypass defrost mode, at this time, the valve port of the first solenoid valve 7 connected to the air inlet 6a of the air storage tank 6 is closed, the valve port of the first solenoid valve 7 connected to the second solenoid valve 8 is opened, the valve port of the first solenoid valve 7 connected to the condenser 5 and the compressor 1 is closed, the valve port of the second solenoid valve 8 connected to the air outlet 6b of the air storage tank 6 is closed, the valve port of the second solenoid valve 8 connected to the first solenoid valve 7 is opened, and the valve port of the second solenoid valve 8 connected to the capillary 3 and the evaporator 2 is closed.

[0081] For example, see Fig. 9 , Fig. 9It is a flow diagram of the refrigerant provided by an embodiment of the present invention in the sixth operating mode. At this time, the charging branch, the discharging branch and the refrigeration cycle are all closed, the defrost branch is connected, and the high-temperature and high-pressure exhaust gas of the compressor 1 flows into the evaporator 2 through the first solenoid valve 7 and the second solenoid valve 8, dissipates heat to the frost layer of the evaporator 2, melts the frost layer, and the refrigerant gas dissipates heat to the external environment, the temperature becomes lower, and then flows back to the compressor 1 to inhale. After being compressed by the compressor 1, the refrigerant is converted into high-temperature and high-pressure exhaust gas again, completing a defrost cycle.

[0082] Furthermore, the corresponding control processes of the above 6 operating modes can refer to Table 1.

[0083] Table 16 Corresponding control processes of the 6 operating modes

[0084]

[0085] In the embodiment of the present invention, the arrangement of the gas storage tank and the coordination of the gas charging branch and the gas discharging branch can flexibly adjust the amount of refrigerant in the refrigeration system. In different operation modes, by controlling the conduction state of the first and second solenoid valves, the refrigerant flow and distribution are optimized, which helps to improve the overall performance and efficiency of the refrigeration system. At the same time, an independent defrosting branch is designed to optimize the defrosting process and improve the overall performance and energy saving effect of the refrigerator.

[0086] Specifically, the controller of the refrigerator is configured to: when it is detected that the refrigerator meets the defrost conditions and no frost blockage occurs, calculate the defrost heat required for the refrigerator to complete the defrost; compare the defrost heat with a preset heat threshold, and determine the corresponding operating mode according to the comparison result; wherein the operating mode includes an inflation mode in which the inflation branch is turned on, an deflation mode in which the deflation branch is turned on, and a bypass defrost mode in which the bypass branch is turned on; and adjust the valve port conductivity state of the first solenoid valve and the second solenoid valve according to the operating mode.

[0087] For example, see Fig.10 , Fig.10It is the first working flow chart of the controller provided by the embodiment of the present invention, and the controller is configured to execute steps S11 to S15. When the whole machine operation time is greater than or equal to the defrost cycle specified by the system, it means that the defrosting condition is met at this time, and then it is determined whether the evaporator is blocked by frost at this time. If frost does not occur, the defrosting heat Q at this time is further calculated, and then the defrosting heat is compared with the heat threshold to determine whether the system is to increase the refrigerant (degassing mode) or reduce the refrigerant (charging mode) or keep the original refrigerant content unchanged and directly perform hot gas bypass defrosting (bypass defrost mode). Since the valve port conduction state of the first solenoid valve and the second solenoid valve is different in different operating modes, after determining the operating mode, the valve port conduction state of the first solenoid valve and the second solenoid valve is adjusted so that the system operates according to the specified operating mode.

[0088] For example, to determine whether the evaporator is blocked by frost, the temperature of the current refrigeration sensor can be recorded every 5 minutes (or 6 minutes, 7 minutes, etc.). When the compressor is turned on, the freezer door is closed, and the freezer is refrigerated, if the temperature sampled for n consecutive times (such as n=8) does not decrease, and the last sampled temperature is higher than the first sampled temperature, it is considered that the freezer is blocked by frost. In this process, if the freezer door is opened or the freezer stops refrigeration, the n sampled values ​​are cleared.

[0089] In the embodiment of the present invention, by detecting whether the refrigerator meets the defrosting conditions and no frost blockage occurs, and calculating the defrosting heat required to complete the defrosting, heat can be accurately provided for the defrosting process according to the actual defrosting requirements, and neither incomplete defrosting due to insufficient heat nor energy waste due to excessive heat. In addition, based on the comparison result of the defrosting heat and the preset heat threshold, it is determined whether the system is operating in the inflation mode, the deflation mode or the bypass defrosting mode, and the best operating mode can be flexibly selected according to different defrosting heat requirements, so that the refrigeration system can meet the defrosting requirements more efficiently. The frost blockage factor is considered in the defrosting control logic to avoid defrosting operations when frost blockage may occur, thereby effectively preventing frost blockage problems caused by improper defrosting and ensuring the stable operation of the refrigeration system.

[0090] Specifically, the controller is further configured to: when it is detected that the refrigerator meets the defrosting conditions and frost blockage occurs, control the refrigerator to enter the second air release mode and the bypass defrost mode in sequence.

[0091] For example, see Fig.11 , Fig.11This is the second working flowchart of the controller provided in an embodiment of the present invention. If frost blockage occurs, it means that the evaporator is severely frosted and needs to be defrosted as soon as possible. Since the frost layer is thicker at this time, the system requires a larger defrosting heat. At this time, the refrigerant in the gas tank is firstly introduced into the system through the second venting mode to participate in the circulation, and then the bypass defrost mode is entered.

[0092] In the embodiment of the present invention, since frost blockage occurs at this time, by controlling the refrigerator to enter the second air release mode and the bypass defrost mode in sequence, the amount of refrigerant in the system can be maximized, thereby being able to provide maximum defrost heat for defrosting, ensuring that the frost layer during frost blockage can be melted, and the smooth operation of the refrigeration system can be quickly restored, thereby avoiding greater failures or long-term adverse effects on the refrigeration effect due to continued frost blockage.

[0093] It should be noted that the amount of frost has a corresponding relationship with the amount of heat required for defrosting. t There are many determination methods (such as calculating through system parameters; using cameras for image monitoring; conducting experiments based on different ambient temperatures, humidity, and usage conditions, etc.). First, the embodiment of the present invention provides a calculation principle: considering the humidity in the refrigerator air, while measuring the humidity in the actual application environment, the moisture content in the air can be obtained; after obtaining the moisture content, the dew point temperature of the air can be determined according to the dew point temperature table. In addition, the amount of humid air entering the refrigerator from the air outside the refrigerator can be estimated based on the number of door openings and the door opening time.

[0094] The frost rate (kg / s) on the surface of the finned tube evaporator can be determined by the change in the moisture content of the humid air flowing through the evaporator, satisfying the following formula:

[0095] m fr =m a (d0-d1);

[0096] Among them, m fr is the frosting rate, in kg / s; m a is the mass flow rate of air flowing through the evaporator, in kg / s; d0 is the humidity content of the supply air, in kg / kg; d1 is the humidity content of the return air, in kg / kg.

[0097] By calculating the frosting rate and the compressor accumulated refrigeration time t c Determine the amount of frost M t , in kg, satisfies the following formula:

[0098] M t =m fr t c ;

[0099] Further, according to the frosting amount M tThe required defrost heat Q can be estimated to satisfy the following formula:

[0100] Q=c pi M t (0-T fv );

[0101] Among them, T fv is the temperature of the frozen evaporation sensor, which approximately represents the frost layer temperature; c pi is the specific heat of frost. Using this formula, the defrosting heat Q can be calculated.

[0102] Specifically, see Fig.11 , the corresponding operation mode is determined according to the comparison result, including the following situations:

[0103] 1.1) When the defrosting heat Q is greater than or equal to the preset maximum heat threshold Q max When Q≥Q max , determine that the operating mode is to enter the second bleed mode (operating mode 3) and the bypass defrost mode (operating mode 6) in sequence.

[0104] For example, since the defrost heat Q value is very large at this time, it means that the system requires a lot of heat for defrosting, and the maximum heat that the hot gas bypass can provide can no longer meet the defrosting requirements. The refrigerant content required by the system at this time is also the largest. Therefore, refrigerant is added to the system through the second bleed mode, thereby making the defrosting efficiency of the bypass defrost mode the highest.

[0105] 1.2) When the defrosting heat Q is less than the maximum heat threshold Q max , and is greater than or equal to the preset minimum heat threshold Q min When Q min ≤Q max , determine that the operating mode is to enter the first deflation mode (operation mode 2) and the bypass defrost mode (operation mode 6) in sequence, or determine that the operating mode is to enter the first inflation mode (operation mode 4) and the bypass defrost mode (operation mode 6) in sequence.

[0106] ​For example, the heat required by the system is not high at this time, and the refrigerant content in the system does not need to be much. If the refrigerant content is high at this time (generally, the refrigerant content of the refrigerator will be higher after a period of defrosting), a part of the refrigerant can be recovered to the gas tank through the first charging mode, and then the bypass defrost mode can be entered; if the refrigerant content is low at this time (generally, the refrigerant content of the refrigerator will be lower after the defrosting starts), relying solely on the refrigerant inside the refrigeration system cannot meet the needs of hot gas bypass defrosting, which may easily cause insufficient defrosting, insufficient return air superheating, resulting in "liquid hammer" in the compressor and other problems. In this case, a part of the refrigerant can be added to the system through the first deflation mode, and then the bypass defrost mode can be entered.

[0107] Furthermore, at this time, the maximum heat threshold Q max and the minimum heat threshold Q min Set an intermediate heat threshold Q0 between min ≤Q max This condition can also be divided into the following two situations: min ≤Q≤Q0、Q0 <Q<Q max .like Fig.11 As shown, the operating modes corresponding to these two situations can be the same.

[0108] 1.3) When the defrosting heat Q is less than the minimum heat threshold Q min When Q min , determine that the operating mode is the bypass defrost mode (operating mode 6), or determine that the operating mode is to enter the second charging mode (operating mode 5) and the bypass defrost mode (operating mode 6) in sequence.

[0109] For example, since the defrost heat Q value is very small at this time, it means that the system is not seriously frosted, the system does not perform hot gas bypass inflation, and only uses the refrigerant mass during normal refrigeration. Hot gas bypass defrosting can also safely complete defrosting. At this time, hot gas bypass defrosting can be performed directly through the bypass defrost mode (such as when the defrost is entered for the first time in this defrost cycle), or the relatively excess refrigerant in the refrigeration system can be discharged to the gas storage tank first, and then hot gas bypass defrost can be performed through the bypass defrost mode (generally, this step is performed after the refrigerator has been defrosting for a period of time).

[0110] ​​In an embodiment of the present invention, by setting a maximum heat threshold and a minimum heat threshold, the defrost heat demand is divided into different intervals, and a corresponding operation mode is formulated for each interval. This precise matching avoids the problem of excessive or insufficient defrosting that may occur when a unified mode is used to cope with different defrosting conditions, thereby improving the defrosting efficiency and effect. In addition, the refrigerant charging and discharging mode is reasonably selected to avoid additional pressure and wear on components such as compressors and solenoid valves caused by excessive charging and discharging of refrigerants. For example, when the defrost heat demand is not high, a high-dose refrigerant charging and discharging mode is not adopted, which reduces the working intensity of the components, helps to extend the service life of these key components, and maintains the long-term stable operation of the refrigeration system. And the ability to flexibly adjust the operation mode according to different defrost heat requirements enables the refrigeration system to maintain good defrosting performance and refrigeration effect under various complex working conditions, thereby enhancing the adaptability and flexibility of the system.

[0111] Specifically, after comparing the defrosting heat with a preset heat threshold, the controller is further configured to: adjust the gear of the compressor according to the comparison result. Exemplarily, the compressor can operate at medium, high and low frequencies, and different gears correspond to different speed ranges.

[0112] In the embodiment of the present invention, different defrost heat requirements mean different difficulties of the defrost task. By comparing the defrost heat with a preset threshold and adjusting the compressor gear accordingly, energy that matches the defrost process can be accurately provided.

[0113] Specifically, see Fig.11 , corresponding to 1.1) to 1.3) above, the step of adjusting the compressor according to the comparison result includes the following situations:

[0114] 2.1) When the defrosting heat Q is greater than or equal to the preset maximum heat threshold Q max When Q≥Q max , control the gear position of the compressor to the first gear position.

[0115] For example, since the frost is severe and the refrigerant content in the system is the highest, the compressor needs to provide maximum power to meet the required defrosting heat demand, and the compressor runs at a high speed. The compressor gear is set to the first gear, because its speed is the highest, and the refrigeration system can quickly generate a large amount of heat for defrosting. This ensures that the frost layer can be removed quickly and effectively in the case of severe frost and arduous defrosting tasks, avoiding the refrigeration performance of the refrigerator being affected for a long time due to the thick frost layer.

[0116] 2.2) When the defrosting heat Q is less than the maximum heat threshold Q max , and is greater than or equal to the preset minimum heat threshold Q min When Q min ≤Q <Qmax , control the gear position of the compressor to the second gear position or the third gear position.

[0117] For example, at this time, the heat required by the system is not high, and the refrigerant content in the system is not much, so the compressor does not need to provide maximum power and can run at medium or low frequency. At this time, the gear of the compressor is the second gear or the third gear. When the defrost heat is in the middle range, the second gear or the third gear can be selected, which enables the system to flexibly adjust the cooling capacity output of the compressor within a certain range according to the actual defrost heat demand, and then convert it into appropriate defrost heat. This flexibility avoids the problem of insufficient or excessive defrosting energy that may be caused by the unified use of a certain gear, ensuring the defrosting effect while optimizing the operating efficiency of the system.

[0118] Furthermore, at this time, the maximum heat threshold Q max and the minimum heat threshold Q min Set an intermediate heat threshold Q0 between min ≤Q max This condition can also be divided into the following two situations: min ≤Q≤Q0、Q0 <Q<Q max .like Fig.11 As shown, the compressor gears corresponding to these two situations are different. <Q<Q max In this case, the system requires a higher defrosting heat Q, so the compressor runs in the second gear; for Q min ≤Q≤Q0, the defrosting heat Q required by the system is relatively low, so the compressor runs in the third gear.

[0119] 2.3) When the defrosting heat Q is less than the minimum heat threshold Q min When Q min , control the gear of the compressor to the third gear; the speed of the first gear is greater than the speed of the second gear, and the speed of the second gear is greater than the speed of the third gear.

[0120] For example, since the defrost heat Q value is very small at this time, it means that the system is lightly frosted, the compressor can run at a low frequency, and the defrost task is relatively easy. At this time, the compressor gear is set to the third gear with the lowest speed, and the defrost work is completed with lower energy consumption, avoiding unnecessary energy waste and achieving energy-saving operation under low defrost heat demand.

[0121] ​​In the embodiment of the present invention, by finely adjusting the compressor gear according to the defrosting heat, accurate energy distribution is achieved, so that the compressor runs at the most appropriate speed under different defrosting requirements, only providing energy required to meet defrosting, avoiding energy waste caused by high-load operation, effectively improving energy utilization efficiency, reducing the overall energy consumption of the refrigerator, and complying with the concept of energy conservation and environmental protection. In addition, the compressor is adjusted to a suitable speed gear according to actual needs in different defrosting scenarios, avoiding long-term high-load operation. High-speed operation will cause the compressor to bear greater pressure and wear. By reasonably reducing the speed, the friction and loss of the internal components of the compressor are reduced, the service life of the compressor is extended, and the maintenance cost and replacement frequency of the equipment are reduced.

[0122] Further, in combination with the above 1.1) to 1.3) and 2.1) to 2.3) processes, the operating logic of the controller is shown in Table 2 below.

[0123] Table 2 Controller operation logic

[0124]

[0125]

[0126] Specifically, in addition to the above-mentioned method of calculating the defrost heat Q by the amount of frost, the embodiment of the present invention also provides another method of calculating the defrost heat Q. At this time, the calculation of the defrost heat Q required for the refrigerator to complete the current defrosting includes the following two cases:

[0127] 3.1) If the defrost heat is calculated for the first time in this defrost cycle, the defrost heat is calculated based on the mass, average temperature and flow rate of the refrigerant and the suction temperature and exhaust temperature of the compressor.

[0128] For example, when calculating the defrost heat for the first time in this defrost cycle, the quality, average temperature, flow rate of the refrigerant, and the suction temperature and exhaust temperature of the compressor are comprehensively considered. The quality and average temperature of the refrigerant reflect the total amount of refrigerant in the refrigeration system and the overall energy state, the flow rate reflects the speed of the refrigeration cycle, and the suction and exhaust temperatures of the compressor are directly related to the heat exchange capacity of the refrigeration system.

[0129] First, the temperature of the refrigerant in the receiver is collected before the defrosting operation. According to the mass M and average temperature T of the refrigerant in the receiver that will participate in the hot gas bypass defrosting, p , calculate the first defrosting heat Q1 that the refrigerant can provide at this time; if Q1=C p0 M*(T p -T1). Or other calculation methods can be used, but it is necessary to ensure that the first defrosting heat Q1 is consistent with the mass M and average temperature T of the refrigerant.p They are directly proportional, C p0 is the specific heat of frost.

[0130] Secondly, the second defrost heat Q2 that the compressor can provide during the defrost operation is estimated based on the speed, suction and exhaust temperatures of the compressor during the defrost operation. The second defrost heat Q2 satisfies the following formula:

[0131] Q2=q m (Cp2T2-Cp1T1)t h ;

[0132] Among them, q m is the refrigerant flow rate at the corresponding compressor operating frequency; T1 is the compressor suction temperature; Cp1 is the specific heat of the refrigerant suction, which is a preset parameter; T2 is the compressor exhaust temperature; Cp2 is the specific heat of the refrigerant exhaust, which is a preset parameter; t h The defrost preset time is generally a defrost time control in the refrigerator control logic, and this time is subject to certain conditions, such as not exceeding 30 minutes, etc. Therefore, the defrost preset time is related to parameters such as the evaporator size, frost amount, and defrost power, and is obtained by calculating or searching these parameters.

[0133] Finally, the defrost heat Q=Q1+Q2 is calculated.

[0134] 3.2) If the defrost heat is not calculated for the first time in this defrost cycle, the defrost heat is calculated based on the flow rate of the refrigerant and the suction temperature and exhaust temperature of the compressor.

[0135] For example, when this defrost cycle is not the first calculation, the defrost heat is calculated based on the refrigerant flow rate and the suction temperature and exhaust temperature of the compressor. At this time, the system is already in the defrost process, and the changes in the refrigerant quality and average temperature are relatively easy to reflect indirectly through the flow rate and compressor temperature changes. m Under the condition of constant), the third defrost heat Q3 that the compressor can provide during the remaining defrost time at time t is estimated to meet the following formula:

[0136] Q3=q m (Cp2T2-Cp1T1)(t h -t p );

[0137] Among them, t p It is the defrost timing, that is, the accumulated defrost time in this defrost cycle.

[0138] Furthermore, the maximum heat threshold Q max is the maximum theoretical hot gas bypass defrost heat, which satisfies the following formula:

[0139] Q max =P*t h =q m max (Cp2T2-Cp1T1)t h ;

[0140] Where P is the compressor power, q m max The maximum flow rate of hot gas bypass refrigerant is obtained according to the displacement of the compressor and the speed of Pmax (maximum power), etc. The mass of refrigerant required for the hot gas bypass defrost cycle, mg max, can be obtained. There is no unique determination method, and the theoretical calculation is only for reference. It is also possible to adjust the refrigerant injection amount to the hot gas bypass defrost system, and select the appropriate mass according to the compressor return air temperature while ensuring that the compressor does not have liquid hammer, or directly determine it through a hot gas bypass defrost experiment. The same method can be used to determine the mass of hot gas bypass defrost refrigerant required for different defrosting heat requirements and different compressor speeds, and then it can be known how much refrigerant needs to be added / reduced in the system.

[0141] In the embodiment of the present invention, accurate calculation of defrost heat helps the system to accurately allocate energy for the defrost process. After the defrost heat is determined by the first calculation, the system can select the appropriate operating mode and compressor gear accordingly to avoid waste due to excessive energy allocation or incomplete defrosting due to insufficient energy. Flexible adjustment during non-first calculations allows the system to dynamically adapt to changes during the defrost process and continuously maintain an efficient defrost state, thereby improving the operating efficiency of the entire refrigeration system. In addition, by calculating the defrost heat in stages and in a targeted manner, it avoids the use of complex multi-parameter calculation methods throughout the entire defrost cycle, reduces unnecessary computing resource consumption and system response time, and enables the system to adjust the operating state more quickly according to the defrost heat, improves the system's real-time response capability, and ensures efficient and stable operation of the refrigeration system.

[0142] Specifically, the refrigerator further comprises a heater, which is arranged at the air intake port of the compressor and is used to increase the air intake temperature of the compressor.

[0143] It is worth noting that the embodiment of the present invention provides two methods for controlling the heater. The first method is to determine whether to turn on the heater based on the intake air temperature, and the second method is to determine whether to turn on the heater based on the comparison relationship between the defrost heat and the heat threshold.

[0144] In the first embodiment, during the defrost operation, the suction temperature of the compressor can be monitored by a temperature sensor. If the suction temperature is higher than the refrigerant saturated gas temperature at the ambient temperature, it means that the compressor can ensure that the refrigerant is in an overheated state, and the compensating electric heater is turned off; if the suction temperature is lower than the refrigerant saturated gas temperature at the ambient temperature, the compensating electric heater is turned on to further increase the refrigerant temperature, thereby preventing the compressor from "liquid hammer" and providing compensation heat for defrosting.

[0145] In a second embodiment, when the defrosting heat is greater than or equal to a preset maximum heat threshold, the controller is further configured to: determine a target power of the heater and control the heater to operate according to the target power. max When the system needs the highest amount of heat, the heater can be turned on synchronously for compensatory heating, and the target power of the heater can be changed dynamically.

[0146] In the embodiment of the present invention, when the defrosting heat provided by the compressor is insufficient, the heat provided by the compensating electric heater is used to provide heat other than the compressor exhaust for hot gas bypass defrosting, thereby preventing the compressor from "liquid hammer". In addition, the heater works in coordination with other components of the refrigeration system to dynamically adjust the power according to the heat difference, making the thermal management of the entire system during the defrosting process more reasonable. This collaborative optimization helps various parts of the system better adapt to different defrosting conditions, enhances the system's ability to cope with complex situations, and improves overall operating performance.

[0147] Specifically, for the above-mentioned second embodiment, determining the target power of the heater includes: calculating the heat difference between the defrost heat and the maximum heat threshold; determining the target power of the heater based on the heat difference; wherein the target power is directly proportional to the heat difference.

[0148] Exemplarily, the power P that the compensation electric heater should provide during the remaining defrosting time satisfies the following formula:

[0149] QQ max =P(t h -t0);

[0150] Wherein, t0 represents the accumulated defrosting time after the defrosting starts.

[0151] In the embodiment of the present invention, the additional heat that the heater needs to provide can be accurately determined through the above calculation method. This precise heat supplement mechanism enables the system to provide an appropriate amount of additional heat only when needed, thereby optimizing energy utilization efficiency.

[0152] Further, see Fig.11During the defrosting process, the defrosting heat Q needs to be updated in real time, and then return to step S24 to determine whether the operation mode needs to be changed. Furthermore, in this process, it is also necessary to determine whether the defrosting exit condition is met at this time. The defrosting exit condition can refer to the prior art, such as through evaporation temperature judgment, duration judgment, etc., and the present invention will not repeat it. In addition, when the defrosting exit condition is met, the hot gas bypass refrigerant is completely charged into the gas storage tank, and then the normal refrigeration mode is entered, that is, the second charging mode (operation mode 5) and the refrigeration mode (operation mode 1) are sequentially entered. It can be understood that if the second charging mode (operation mode 5) has been executed in step S27 at this time, then after the defrosting exit condition is met, the excess refrigerant content in the system has been reduced, so the refrigeration mode (operation mode 1) can be directly entered.

[0153] Compared with the prior art, the refrigerator disclosed in the present invention introduces a gas storage tank that can adjust the amount of refrigerant in the hot gas bypass defrosting technology, thereby forming an inflation branch, an exhaust branch and a defrost branch that are independent of the refrigeration cycle. By detecting whether the refrigerator meets the defrosting conditions and no frost blockage occurs, and calculating the defrosting heat required to complete this defrosting, it can accurately provide heat for the defrosting process according to the actual defrosting needs, and will not cause incomplete defrosting due to insufficient heat, nor will it cause energy waste due to excessive heat. In addition, according to the comparison result of the defrosting heat and the preset heat threshold, it is determined that the system is operating in the inflation mode, exhaust mode or bypass defrosting mode, and the best operating mode can be flexibly selected according to different defrosting heat requirements, so that the refrigeration system can more efficiently meet the defrosting requirements.

[0154] See also Fig.12 , Fig.12 The present invention provides a flowchart of a defrost control method for a refrigerator, which is implemented by a controller in the refrigerator. The refrigerator includes a gas storage tank and a compressor, a condenser, and an evaporator connected in sequence through pipelines; wherein the gas storage tank is connected to a pipeline between the compressor and the condenser through a first solenoid valve to form a gas branch; and is connected to a pipeline between the evaporator and the condenser through a second solenoid valve to form a defrost branch; a defrost branch is also formed between the first solenoid valve and the second solenoid valve; the defrost control method for the refrigerator includes:

[0155] S1. When it is detected that the refrigerator meets the defrosting conditions and no frost blockage occurs, the defrosting heat required by the refrigerator to complete the current defrosting is calculated;

[0156] S2. Compare the defrosting heat with a preset heat threshold, and determine a corresponding operation mode according to the comparison result; wherein the operation mode includes an inflation mode in which the inflation branch is turned on, an deflation mode in which the deflation branch is turned on, and a bypass defrosting mode in which the bypass branch is turned on;

[0157] S3. Adjusting the valve port conduction states of the first solenoid valve and the second solenoid valve according to the operation mode.

[0158] Specifically, the inflation mode includes a first inflation mode and a second inflation mode, and the refrigerant inflation amount of the first inflation mode is less than the refrigerant inflation amount of the second inflation mode; the deflation mode includes a first deflation mode and a second deflation mode, and the refrigerant deflation amount of the first deflation mode is less than the refrigerant deflation amount of the second deflation mode.

[0159] Specifically, the method further includes: when it is detected that the refrigerator meets the defrosting conditions and frost blockage occurs, controlling the refrigerator to enter the second air release mode and the bypass defrost mode in sequence.

[0160] Specifically, determining the corresponding operating mode based on the comparison result includes: when the defrost heat is greater than or equal to a preset maximum heat threshold, determining the operating mode to be sequentially entering the second air release mode and the bypass defrost mode; when the defrost heat is less than the maximum heat threshold, and greater than or equal to a preset minimum heat threshold, determining the operating mode to be sequentially entering the first air release mode and the bypass defrost mode, or determining the operating mode to be sequentially entering the first inflation mode and the bypass defrost mode; when the defrost heat is less than the minimum heat threshold, determining the operating mode to be the bypass defrost mode, or determining the operating mode to be sequentially entering the second inflation mode and the bypass defrost mode.

[0161] Specifically, after comparing the defrost heat with a preset heat threshold, the method further includes: adjusting the gear position of the compressor according to the comparison result.

[0162] Specifically, adjusting the gear of the compressor according to the comparison result includes: when the defrost heat is greater than or equal to a preset maximum heat threshold, controlling the gear of the compressor to the first gear; when the defrost heat is less than the maximum heat threshold, and greater than or equal to a preset minimum heat threshold, controlling the gear of the compressor to the second gear or the third gear; when the defrost heat is less than the minimum heat threshold, controlling the gear of the compressor to the third gear; the rotation speed of the first gear is greater than the rotation speed of the second gear, and the rotation speed of the second gear is greater than the rotation speed of the third gear.

[0163] Specifically, the calculation of the defrost heat required for the refrigerator to complete the defrost includes: if the defrost heat is calculated for the first time in this defrost cycle, the defrost heat is calculated based on the mass, average temperature and flow rate of the refrigerant and the suction temperature and exhaust temperature of the compressor; if the defrost heat is not calculated for the first time in this defrost cycle, the defrost heat is calculated based on the flow rate of the refrigerant and the suction temperature and exhaust temperature of the compressor.

[0164] Specifically, the refrigerator also includes a heater arranged at the air intake port of the compressor. When the defrost heat is greater than or equal to a preset maximum heat threshold, the method also includes: determining a target power of the heater and controlling the heater to operate according to the target power.

[0165] Specifically, determining the target power of the heater includes: calculating the heat difference between the defrost heat and the maximum heat threshold; determining the target power of the heater according to the heat difference; wherein the target power is proportional to the heat difference.

[0166] It is worth noting that the specific working process of the defrost control method for the refrigerator described in the embodiment of the present invention can refer to the working process of the controller in the refrigerator described in the above embodiment, which will not be repeated here.

[0167] In the embodiment of the present invention, by detecting whether the refrigerator meets the defrosting conditions and no frost blockage occurs, and calculating the defrosting heat required to complete the defrosting, heat can be accurately provided for the defrosting process according to the actual defrosting demand, and neither incomplete defrosting due to insufficient heat nor energy waste due to excessive heat. In addition, according to the comparison result of the defrosting heat and the preset heat threshold, it is determined that the system is operating in the inflation mode, the deflation mode or the bypass defrosting mode, and the best operation mode can be flexibly selected according to different defrosting heat requirements, so that the refrigeration system can meet the defrosting requirements more efficiently. The setting of the gas storage tank and the coordination of the inflation branch and the deflation branch can flexibly adjust the amount of refrigerant in the refrigeration system. Under different operation modes, by controlling the conduction state of the first and second solenoid valves, the optimization of the refrigerant flow and distribution is achieved, which helps to improve the overall performance and efficiency of the refrigeration system. The frost blockage factor is considered in the defrosting control logic to avoid defrosting operation when frost blockage may occur, thereby effectively preventing the frost blockage problem caused by improper defrosting and ensuring the stable operation of the refrigeration system.

[0168] The above is a preferred embodiment of the present invention. It should be pointed out that a person skilled in the art can make several improvements and modifications without departing from the principle of the present invention. These improvements and modifications are also considered to be within the scope of protection of the present invention.

Claims

1. A refrigerator, characterized in that: include: a box body, in which at least one storage chamber is formed, and the storage chamber includes at least a refrigerating chamber; A refrigeration system, used to provide coldness for the refrigerator, the refrigeration system comprising a compressor, a condenser and an evaporator connected in sequence through pipelines; An air storage tank, used to reduce or increase the amount of refrigerant in the refrigeration system, comprises an air inlet and an air outlet, wherein the air inlet is connected to the pipe between the compressor and the condenser via a first solenoid valve to form an air charging branch of the air storage tank; the air outlet is connected to the pipe between the evaporator and the condenser via a second solenoid valve to form an air discharging branch of the air storage tank; wherein a defrost branch independent of the air storage tank is also formed between the first solenoid valve and the second solenoid valve.

2. The refrigerator according to claim 1, characterized in that: The refrigerator further comprises: A controller, the controller being configured to: When it is detected that the refrigerator meets the defrosting conditions and no frost blockage occurs, the defrosting heat required by the refrigerator to complete the current defrosting is calculated; The defrosting heat is compared with a preset heat threshold, and a corresponding operation mode is determined according to the comparison result; wherein the operation mode includes an inflation mode in which the inflation branch is turned on, an deflation mode in which the deflation branch is turned on, and a bypass defrosting mode in which the bypass branch is turned on; The valve port conduction states of the first solenoid valve and the second solenoid valve are adjusted according to the operation mode.

3. The refrigerator according to claim 2, characterized in that: The inflation mode includes a first inflation mode and a second inflation mode, and the refrigerant inflation amount of the first inflation mode is less than the refrigerant inflation amount of the second inflation mode; the deflation mode includes a first deflation mode and a second deflation mode, and the refrigerant deflation amount of the first deflation mode is less than the refrigerant deflation amount of the second deflation mode.

4. The refrigerator according to claim 3, characterized in that: Determining the corresponding operation mode according to the comparison result includes: When the defrosting heat is greater than or equal to a preset maximum heat threshold, determining that the operation mode is to enter the second air release mode and the bypass defrosting mode in sequence; When the defrost heat is less than the maximum heat threshold and greater than or equal to the preset minimum heat threshold, determining that the operation mode is to sequentially enter the first deflation mode and the bypass defrost mode, or determining that the operation mode is to sequentially enter the first inflation mode and the bypass defrost mode; When the defrost heat is less than the minimum heat threshold, the operation mode is determined to be the bypass defrost mode, or the operation mode is determined to enter the second charging mode and the bypass defrost mode in sequence.

5. The refrigerator according to claim 2, characterized in that: After comparing the defrost heat with a preset heat threshold, the controller is further configured to: The gear position of the compressor is adjusted according to the comparison result.

6. The refrigerator according to claim 5, characterized in that: The step of adjusting the gear position of the compressor according to the comparison result comprises: When the defrosting heat is greater than or equal to a preset maximum heat threshold, controlling the gear position of the compressor to the first gear position; When the defrosting heat is less than the maximum heat threshold and greater than or equal to the preset minimum heat threshold, controlling the gear position of the compressor to the second gear position or the third gear position; When the defrost heat is less than the minimum heat threshold, the gear of the compressor is controlled to be the third gear; the rotation speed of the first gear is greater than the rotation speed of the second gear, and the rotation speed of the second gear is greater than the rotation speed of the third gear.

7. The refrigerator according to claim 2, characterized in that: The calculating of the defrosting heat required by the refrigerator to complete the current defrosting comprises: If the defrost heat is calculated for the first time in this defrost cycle, the defrost heat is calculated based on the mass, average temperature and flow rate of the refrigerant and the suction temperature and exhaust temperature of the compressor; If the defrost heat is not calculated for the first time in this defrost cycle, the defrost heat is calculated according to the flow rate of the refrigerant and the suction temperature and exhaust temperature of the compressor.

8. The refrigerator according to claim 2, characterized in that: The refrigerator further comprises: A heater, disposed at the air intake port of the compressor, for increasing the air intake temperature of the compressor; When the defrosting heat is greater than or equal to a preset maximum heat threshold, the controller is further configured to: A target power of the heater is determined, and the heater is controlled to operate according to the target power.

9. The refrigerator according to claim 8, characterized in that: The determining the target power of the heater comprises: calculating a heat difference between the defrost heat and the maximum heat threshold; The target power of the heater is determined according to the heat difference; wherein the target power is proportional to the heat difference.

10. A refrigerator defrosting control method, characterized in that: The refrigerator comprises a gas storage tank and a compressor, a condenser and an evaporator connected in sequence through pipelines; wherein the gas storage tank is connected to the pipeline between the compressor and the condenser through a first solenoid valve to form a gas branch; and is connected to the pipeline between the evaporator and the condenser through a second solenoid valve to form a defrosting branch; a defrosting branch is also formed between the first solenoid valve and the second solenoid valve; the method comprises: When it is detected that the refrigerator meets the defrosting conditions and no frost blockage occurs, the defrosting heat required by the refrigerator to complete the current defrosting is calculated; The defrosting heat is compared with a preset heat threshold, and a corresponding operation mode is determined according to the comparison result; wherein the operation mode includes an inflation mode in which the inflation branch is turned on, an deflation mode in which the deflation branch is turned on, and a bypass defrosting mode in which the bypass branch is turned on; The valve port conduction states of the first solenoid valve and the second solenoid valve are adjusted according to the operation mode.

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