Control method for heat pump system, heat pump system, and storage medium

Abstract

The application discloses a control method of a heat pump system, the heat pump system and a storage medium, and relates to the technical field of heat pumps. The heat pump system comprises a refrigerant circulating device, a heat exchange module and a liquid storage device. The second heat exchanger in the refrigerant circulating device is in heat exchange connection with the heat exchange module. The heat exchange module is in communication with the liquid storage device. A flow regulating module is arranged between the heat exchange module and the liquid storage device. The method comprises the following steps: controlling the refrigerant circulating device to operate so that the first heat exchanger is in an evaporation state and the second heat exchanger is in a condensation state, and controlling the flow regulating module to operate so that the liquid in the liquid storage device flows into the heat exchange module; under the condition that a defrosting condition is met, controlling the flow regulating module to reduce the liquid flow of the liquid storage device flowing into the heat exchange module; and under the condition that a first preset condition is met, controlling the refrigerant circulating device to operate to defrost the first heat exchanger. The defrosting condition indicates that the first heat exchanger has a risk of frosting. The application aims to improve the defrosting efficiency and the system energy efficiency.

Description

Technical Field

[0001] This application relates to the field of heat pump technology, and in particular to control methods for heat pump systems, heat pump systems, and storage media. Background Technology

[0002] In heat pump systems equipped with a liquid storage device (such as heat pump water heaters), the liquid is usually drawn from one end of the liquid storage device to the heat pump unit for temperature regulation, and then returns to the liquid storage device from the other end to form a circulating temperature regulation.

[0003] In low-temperature environments, the heat exchanger in the heat pump system, which is in an evaporation state, is prone to frosting. Currently, when the defrosting start-up conditions are met, the system immediately switches to defrosting operation, using the heat generated by the compressor to defrost the frosted heat exchanger. However, this method has the problems of poor defrosting efficiency and high energy consumption. Summary of the Invention

[0004] The main objective of this application is to provide a control method for a heat pump system, a heat pump system, and a storage medium, with the aim of improving defrosting efficiency and system energy efficiency.

[0005] To achieve the above objectives, this application proposes a control method for a heat pump system. The heat pump system includes a refrigerant circulation device, a heat exchange module, and a liquid storage device. The refrigerant circulation device includes a compressor and a first heat exchanger, a throttling device, and a second heat exchanger connected in sequence. The second heat exchanger is heat-exchange connected to the heat exchange module, and the heat exchange module is connected to the liquid storage device. A flow regulation module is installed in the connecting pipeline between the heat exchange module and the liquid storage device. The method includes:

[0006] The refrigerant circulation device is controlled to operate so that the first heat exchanger is in an evaporation state and the second heat exchanger is in a condensation state, and the flow regulation module is controlled to operate so that the liquid in the liquid storage device flows into the heat exchange module;

[0007] When defrosting conditions are met, the flow regulation module is controlled to reduce the liquid flow rate from the liquid storage device into the heat exchange module;

[0008] Under the condition that the first preset condition is met, the refrigerant circulation device is controlled to operate in order to defrost the first heat exchanger;

[0009] The defrosting conditions indicate that the first heat exchanger is at risk of frosting.

[0010] In one embodiment, the step of controlling the flow regulation module to reduce the liquid flow rate from the liquid storage device into the heat exchange module includes:

[0011] The flow regulation module is controlled to reduce the flow rate of liquid flowing from the liquid storage device into the heat exchange module to the target flow rate;

[0012] The target flow rate is negatively correlated with the frost thickness of the first heat exchanger.

[0013] In one embodiment, before the step of controlling the flow regulation module to reduce the liquid flow rate from the liquid storage device into the heat exchange module to the target flow rate, the method further includes:

[0014] Under the condition that defrosting is met, the target flow rate is determined based on the temperature of the first heat exchanger, and the target flow rate is positively correlated with the temperature of the first heat exchanger.

[0015] In one embodiment, the first preset condition includes at least one of the following:

[0016] The time interval between the initial time when the defrosting conditions are met and the current time is greater than or equal to a preset time.

[0017] The temperature rise of the liquid in the heat exchange module from the initial moment to the current moment is greater than or equal to the preset temperature.

[0018] In one embodiment, the throttling device includes an electronic expansion valve, and the step of controlling the refrigerant circulation device to defrost the first heat exchanger includes:

[0019] Control the electronic expansion valve to increase its opening to the defrosting opening.

[0020] In one embodiment, the step of controlling the refrigerant circulation device to defrost the first heat exchanger further includes:

[0021] The flow regulation module is controlled to adjust the liquid flow rate from the liquid storage device into the heat exchange module to the defrosting flow rate, and / or the compressor is controlled to operate at the defrosting frequency.

[0022] In one embodiment, the step of controlling the refrigerant circulation device to defrost the first heat exchanger when the first preset condition is met includes:

[0023] Under the condition that the first preset condition is met, the flow regulation module is controlled to adjust the flow rate of the liquid flowing from the liquid storage device into the heat exchange module to the defrosting flow rate;

[0024] Under the condition that the second preset condition is met, the compressor is controlled to operate at the defrosting frequency, and the electronic expansion valve is controlled to increase to the transition opening.

[0025] Under the condition that the third preset condition is met, the electronic expansion valve is controlled to increase its opening to the defrosting opening.

[0026] Wherein, the transition opening degree is less than the defrosting opening degree.

[0027] In one embodiment, the step of controlling the refrigerant circulation device to defrost the first heat exchanger includes:

[0028] Based on the target heat relationship, the electronic expansion valve is controlled to increase its opening to the defrosting opening, the flow regulation module is controlled to adjust the liquid flow rate from the liquid storage device into the heat exchange module to the defrosting flow rate, and the compressor is controlled to operate at the defrosting frequency;

[0029] The target heat relationship includes defrosting heat being greater than or equal to the heat supplied by the second heat exchanger, and / or the target heat relationship includes the difference between defrosting heat and the heat supplied by the second heat exchanger being less than a preset heat.

[0030] In one embodiment, the step of controlling the flow regulation module to reduce the liquid flow rate from the liquid storage device into the heat exchange module when the defrosting conditions are met includes:

[0031] When the defrosting conditions are met, the compressor is controlled to operate at a reduced frequency and the flow regulation module is controlled to reduce the liquid flow rate from the liquid storage device into the heat exchange module, so that the temperature of the second heat exchanger increases and the increased temperature of the second heat exchanger is lower than the preset temperature.

[0032] In one embodiment, the compressor's frequency reduction ratio is greater than the reduction ratio of the liquid flow rate into the heat exchange module.

[0033] In addition, to achieve the above objectives, this application also proposes a heat pump system, which includes a control device, a refrigerant circulation device, a heat exchange module, and a liquid storage device. The refrigerant circulation device includes a compressor and a first heat exchanger, a throttling device, and a second heat exchanger connected in sequence. The second heat exchanger is heat-exchange connected to the heat exchange module, and the heat exchange module is connected to the liquid storage device. A flow regulation module is provided in the connecting pipeline between the heat exchange module and the liquid storage device.

[0034] The refrigerant circulation device is communicatively connected to the control device, which includes a memory, a processor, and a computer program stored in the memory and executable on the processor. The computer program is configured to implement the steps of the control method for the heat pump system as described above.

[0035] In addition, to achieve the above objectives, this application also proposes a storage medium, which is a computer-readable storage medium, on which a computer program is stored, and when the computer program is executed by a processor, it implements the steps of the control method for the heat pump system as described above.

[0036] One or more technical solutions proposed in this application have at least the following technical effects: Based on a heat pump system, in the refrigerant circulation device of the system, the second heat exchanger is connected to the heat exchange module of the liquid storage device. When the second heat exchanger is in a condensing state and heating the liquid in the liquid storage device, and the first heat exchanger is in an evaporating state and there is a risk of frosting, the defrosting operation is not started immediately. Instead, the flow rate of the liquid flowing from the liquid storage device into the heat exchange module is reduced by the flow regulation module to increase the temperature of the second heat exchanger. This can store heat for the subsequent defrosting process, which is beneficial to improving defrosting efficiency and reducing system energy consumption during the defrosting process, thereby improving defrosting efficiency and system energy efficiency. Attached Figure Description

[0037] The accompanying drawings, which are incorporated in and form part of this specification, illustrate embodiments consistent with this application and, together with the description, serve to explain the principles of this application.

[0038] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, for those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0039] Figure 1 This is a schematic diagram of the system structure of an embodiment of the heat pump system of this application;

[0040] Figure 2 This is a schematic diagram of the refrigerant flow path in the refrigerant circulation device of the heat pump system of this application;

[0041] Figure 3 This is a schematic diagram of the equipment structure of the hardware operating environment involved in the control method of the heat pump system in the embodiments of this application;

[0042] Figure 4 A flowchart illustrating an embodiment of the control method for the heat pump system of this application;

[0043] Figure 5 This is a flowchart illustrating Embodiment 2 of the control method for the heat pump system of this application.

[0044] Figure 6 This is a flowchart illustrating a third embodiment of the control method for the heat pump system of this application.

[0045] The purpose, features, and advantages of this application will be further explained in conjunction with the embodiments and with reference to the accompanying drawings. Detailed Implementation

[0046] It should be understood that the specific embodiments described herein are merely illustrative of the technical solutions of this application and are not intended to limit this application.

[0047] To better understand the technical solution of this application, a detailed description will be provided below in conjunction with the accompanying drawings and specific implementation methods.

[0048] The main solution of this application embodiment is: a control method based on a heat pump system, the heat pump system including a refrigerant circulation device, a heat exchange module, and a liquid storage device. The refrigerant circulation device includes a compressor and a first heat exchanger, a throttling device, and a second heat exchanger connected in sequence. The second heat exchanger is heat-exchange connected to the heat exchange module, the heat exchange module is connected to the liquid storage device, and a flow regulation module is provided in the connecting pipeline between the heat exchange module and the liquid storage device. The method includes: controlling the operation of the refrigerant circulation device to make the first heat exchanger in an evaporation state and the second heat exchanger in a condensation state; controlling the operation of the flow regulation module to make the liquid in the liquid storage device flow into the heat exchange module; when defrosting conditions are met, controlling the flow regulation module to reduce the liquid flow rate from the liquid storage device into the heat exchange module; and when a first preset condition is met, controlling the operation of the refrigerant circulation device to defrost the first heat exchanger; wherein, the defrosting condition indicates that the first heat exchanger has a risk of frosting.

[0049] In this embodiment, for ease of description, the following description uses a heat pump system as the implementing entity.

[0050] In related technologies, heat exchangers in heat pump systems operating in evaporation states are prone to frosting when running in low-temperature environments. Currently, when the defrosting start-up conditions are met, the system immediately switches to defrosting operation, using the heat generated by the compressor to defrost the frosted heat exchangers. However, this method suffers from poor defrosting efficiency and high energy consumption.

[0051] This application provides the above-mentioned solution: when the second heat exchanger is in a condensing state and heating the liquid in the liquid storage device, and the first heat exchanger is in an evaporating state and there is a risk of frosting, the defrosting operation is not started immediately. Instead, the flow rate of the liquid flowing from the liquid storage device into the heat exchange module is reduced by the flow regulation module to increase the temperature of the second heat exchanger. This can store heat for the subsequent defrosting process, which is beneficial to improving defrosting efficiency and reducing the system energy consumption of the defrosting process, thereby improving defrosting efficiency and system energy efficiency.

[0052] This application provides a heat pump system, which in this embodiment is a heat pump water heater. In other embodiments, the heat pump system may also be a composite system that simultaneously regulates liquid temperature and air temperature, etc.

[0053] In this embodiment, refer to Figure 1 and Figure 2 , Figure 1The middle arrow indicates the direction of liquid flow. The heat pump system includes a refrigerant circulation device 200 and a liquid storage device 300. The refrigerant circulation device 200 includes a compressor 21 and a first heat exchanger 22, a throttling device 23 and a second heat exchanger 24 connected in sequence. The second heat exchanger 24 is configured to regulate the temperature of the liquid in the liquid storage device 300.

[0054] In this embodiment, the liquid storage device 300 is a water tank. In other embodiments, the liquid storage device 300 may also be a device for storing liquids other than water.

[0055] The first heat exchanger 22 is equipped with a corresponding fan 25. When the fan 25 is turned on, it can drive the air in the environment where the first heat exchanger 22 is located to exchange heat with the first heat exchanger 22. In this embodiment, the fan 25, the first heat exchanger 22 and the second heat exchanger 24 are all located in the mounting cavity of the refrigerant circulation device 200.

[0056] When the second heat exchanger 24 is in a condensing state, it can increase the temperature of the liquid in the liquid storage device 300. When the second heat exchanger 24 is in an evaporating state, it can decrease the temperature of the liquid in the liquid storage device 300.

[0057] In this embodiment, the throttling device 23 includes an electronic expansion valve.

[0058] In one implementation, refer to Figure 2 The exhaust port of compressor 21, the second heat exchanger 24, the throttling device 23, the first heat exchanger 22, and the return port of compressor 21 are connected in sequence. When compressor 21 is turned on, the refrigerant discharged by compressor 21 flows sequentially through the second heat exchanger 24, the throttling device 23, and the first heat exchanger 22 before returning to compressor 21. When the throttling device 23 is in a throttling state, the second heat exchanger 24 is in a condensing state, and the first heat exchanger 22 is in an evaporating state; when the throttling device 23 is in a non-throttling state, both the first heat exchanger 22 and the second heat exchanger 24 are in a heat-releasing state.

[0059] In another implementation, the refrigerant circulation device 200 further includes a reversing assembly (e.g., a four-way valve). The exhaust port of the compressor 21, the return port of the compressor 21, the first heat exchanger 22, and the second heat exchanger 24 are all connected to the reversing assembly. The reversing assembly has a first operating state and a second operating state. When the reversing assembly is operating in the first operating state, the exhaust port is connected to the second heat exchanger 24, and the return port is connected to the first heat exchanger 22. When the reversing assembly is operating in the second operating state, the exhaust port is connected to the first heat exchanger 22, and the return port is connected to the second heat exchanger 24. Specifically, when the reversing assembly is operating in the first operating state, if the throttling device 23 is in a throttling state, the second heat exchanger 24 is in a condensing state, and the first heat exchanger 22 is in an evaporating state. If the throttling device 23 is not in a throttling state, both the second heat exchanger 24 and the first heat exchanger 22 are in a heat-releasing state. When the reversing assembly is operating in the second operating state, if the throttling device 23 is in a throttling state, the second heat exchanger 24 is in an evaporating state, and the first heat exchanger 22 is in a condensing state.

[0060] In this embodiment, refer to Figure 1 The heat pump system also includes a heat exchange module 400, which is connected to a liquid storage device 300. The liquid in the liquid storage device 300 can flow into the heat exchange module 400 to exchange heat with the second heat exchanger 24.

[0061] In this embodiment, the heat exchange module 400 is disposed within the refrigerant circulation device 200. The refrigerant circulation device 200 and the liquid storage device 300 are disposed independently of each other. The heat exchange module 400 and the second heat exchanger 24 are integrated to form a plate heat exchanger.

[0062] A flow regulation module 301 can be installed in the connecting pipeline between the heat exchange module 400 and the liquid storage device 300 to regulate the flow rate of liquid flowing from the liquid storage device 300 into the heat exchange module 400. In this embodiment, the flow regulation module 301 includes a water pump. When the water pump is turned on, liquid from the liquid storage device 300 flows into the heat exchange module 400; when the water pump is turned off, liquid from the liquid storage device 300 stops flowing into the heat exchange module 400. The flow rate can be regulated by adjusting the current, power, or speed when the water pump is turned on.

[0063] In this embodiment, the liquid storage device 300 is provided with an outlet and a return port, which are respectively connected to the two ends of the heat exchange module 400. After the liquid flows into the heat exchange module 400 for heat exchange, it can flow back to the liquid storage device 300.

[0064] In this embodiment, the liquid outlet and the liquid return outlet are located at both ends of the liquid storage device 300.

[0065] In this embodiment, the liquid outlet and the liquid return port are arranged vertically at intervals, with the liquid outlet located at the bottom of the liquid storage device 300 and the liquid return port located at the top of the liquid storage device 300. In other implementations, the liquid outlet is located at the top of the liquid storage device 300 and the liquid return port is located at the bottom of the liquid storage device 300.

[0066] In other embodiments, the outlet and return outlet may also be spaced laterally.

[0067] In other embodiments, the second heat exchanger 24 may also be directly connected to the liquid storage device 300 for heat exchange, and the second heat exchanger 24 may be disposed on the outer wall of the liquid storage device 300 or inside the liquid storage device 300.

[0068] Reference Figure 2 and Figure 3 The heat pump system also includes a temperature sensor 01, which can be installed on the first heat exchanger 22 to detect the temperature of the first heat exchanger. For example, the temperature sensor 01 can be installed in the middle of the coil of the first heat exchanger 22 or at the refrigerant outlet, etc.

[0069] Combination Figure 3 The heat pump system also includes a control device 100, and the aforementioned refrigerant circulation device 200, flow regulation module 301, and temperature sensor 01 are all communicatively connected to the control device 100.

[0070] The control device 100 includes: at least one processor 1001; and a memory 1002 communicatively connected to the at least one processor 1001, and a timer 1003, etc.; wherein the memory 1002 stores instructions that can be executed by the at least one processor 1001, the instructions being executed by the at least one processor 1001 to enable the at least one processor 1001 to execute the control method of the heat pump system in the following embodiment.

[0071] The following is for reference. Figure 3 The diagram illustrates a structural schematic of a control device 100 suitable for implementing embodiments of this application. The heat pump system in the embodiments of this application may include, but is not limited to, mobile terminals such as mobile phones, laptops, digital radio receivers, PDAs (Personal Digital Assistants), PADs (Portable Application Descriptions), PMPs (Portable Media Players), in-vehicle terminals (e.g., in-vehicle navigation terminals), and fixed terminals such as digital TVs and desktop computers. Figure 3 The control device 100 shown is merely an example and should not impose any limitation on the functionality and scope of use of the embodiments of this application.

[0072] like Figure 3 As shown, the control device 100 may include a processor 1001 (e.g., a central processing unit, a graphics processing unit, etc.), which can perform various appropriate actions and processes according to a program stored in memory 1002. The program in memory 1002 may be a program in read-only memory (ROM) or a program loaded from a storage device into random access memory (RAM). The RAM also stores various programs and data required for the operation of the control device 100. The processor 1001 and memory 1002 (ROM and RAM) are interconnected via a bus. Input / output (I / O) interfaces are also connected to the bus. Typically, the following systems can be connected to the I / O interface: input devices including, for example, touchscreens, touchpads, keyboards, mice, image sensors, microphones, accelerometers, gyroscopes, etc.; output devices including, for example, liquid crystal displays (LCDs), speakers, vibrators, etc.; storage devices including, for example, magnetic tapes, hard disks, etc.; and communication devices. The communication device allows the control device 100 to communicate wirelessly or wiredly with other devices to exchange data. Although the control unit 100 with various systems is shown in the figure, it should be understood that it is not required to implement or have all of the systems shown. More or fewer systems may be implemented or have alternatively.

[0073] Specifically, according to the embodiments disclosed in this application, the method flow described in the following embodiments can be implemented as a computer software program. For example, the embodiments disclosed in this application include a computer program product comprising a computer program carried on a computer-readable medium, the computer program containing program code for performing the methods shown in the flowchart. In such an embodiment, the computer program can be downloaded and installed from a network via a communication device, or installed from memory 1002. When the computer program is executed by processor 1001, it performs the functions defined in the control method of the heat pump system of the embodiments disclosed in this application.

[0074] The heat pump system provided in this application, employing the control method of the heat pump system in the following embodiments, can solve the technical problem of how to improve defrosting efficiency and system energy efficiency. Compared with the prior art, the beneficial effects of the heat pump system provided in this application are the same as the beneficial effects of the control method of the heat pump system provided in the following embodiments, and other technical features of this heat pump system are the same as those disclosed in the method of the following embodiments, and will not be repeated here.

[0075] It should be noted that the executing entity in this embodiment can be a computing service device with data processing, network communication, and program execution functions, such as a tablet computer, personal computer, or mobile phone, or an electronic device or heat pump system capable of performing the above functions. The following description uses a heat pump system as an example to illustrate this embodiment and the subsequent embodiments.

[0076] Based on this, embodiments of this application provide a control method for a heat pump system, referring to... Figure 4 , Figure 4 This is a flowchart illustrating the first embodiment of the control method for the heat pump system of this application.

[0077] In this embodiment, the control method of the heat pump system includes steps S10 to S30:

[0078] Step S10: Control the operation of the refrigerant circulation device to make the first heat exchanger be in an evaporation state and the second heat exchanger be in a condensation state, and control the operation of the flow regulation module to make the liquid in the liquid storage device flow into the heat exchange module;

[0079] During the operation of the flow regulation module, the liquid flow rate flowing into the heat exchange module can be a pre-set fixed flow rate, or it can be determined according to the actual operating conditions of the system, such as the flow rate determined according to the user-set temperature and / or the user-set hot water volume.

[0080] In one implementation, the compressor's exhaust port, second heat exchanger, throttling device, first heat exchanger, and compressor return port are sequentially connected in the refrigerant circulation device. When the compressor is turned on and the throttling device is in a throttling state, the refrigerant discharged by the compressor flows sequentially through the second heat exchanger, the throttling device, and the first heat exchanger before returning to the compressor. The first heat exchanger is in an evaporation state, and the second heat exchanger is in a condensation state, which can heat the liquid flowing through the heat exchange module.

[0081] In another implementation, the refrigerant circulation device also includes a reversing assembly. The compressor's exhaust port, compressor's return port, first heat exchanger, and second heat exchanger are all connected to the reversing assembly. When the reversing assembly is in a first operating state, the throttling device is in a throttling state, and the compressor is turned on, the refrigerant discharged by the compressor flows sequentially through the second heat exchanger, the throttling device, and the first heat exchanger before returning to the compressor. The first heat exchanger is in an evaporating state, and the second heat exchanger is in a condensing state, which can heat the liquid flowing through the heat exchange module.

[0082] Step S20: When the defrosting conditions are met, control the flow regulation module to reduce the liquid flow rate from the liquid storage device into the heat exchange module; wherein, the defrosting conditions indicate that the first heat exchanger is at risk of frosting.

[0083] Defrosting conditions may include the operating parameters of the refrigerant circulation device itself and / or the environmental parameters of the environment in which the refrigerant circulation device is located, when the first heat exchanger is frosted and defrosting is required. For example, the continuous operating time of the first heat exchanger in the evaporation state and the second heat exchanger in the condensation state is greater than or equal to a preset duration and / or the ambient temperature is lower than a preset ambient temperature threshold and / or the temperature of the first heat exchanger is lower than a preset temperature threshold, etc.

[0084] The operating parameters (such as current, speed, or power) of the flow control module are adjusted according to the operating adjustment parameters to reduce the liquid flow rate from the storage device into the heat exchange module. These operating adjustment parameters can be pre-set fixed parameters or parameters determined based on the actual operating conditions of the system. The operating adjustment parameters may include: the adjustment range of the liquid flow rate into the heat exchange module, or the target flow rate after the liquid flow rate into the heat exchange module is reduced, or the decrease in the current of the flow control module, or the decrease in the power of the flow control module, or the decrease in the speed of the flow control module, etc.

[0085] The flow regulation module controls the operation to reduce the liquid flow rate into the heat exchange module. The liquid flow rate into the heat exchange module can be continuously reduced to the target flow rate at a preset rate or reduced to the target flow rate in stages.

[0086] During the process of controlling the flow regulation module to reduce the liquid flow from the liquid storage device into the heat exchange module, the compressor, fan, and throttling device in the refrigerant circulation device can all maintain their current operating parameters, or the operating parameters of at least one of the compressor, fan, and throttling device can be adjusted according to the operating adjustment parameters of the flow regulation module.

[0087] Step S30: Under the condition that the first preset condition is met, control the operation of the refrigerant circulation device to defrost the first heat exchanger.

[0088] The first preset condition indicates that the defrosting heat storage has reached the target heat. In this embodiment, the first preset condition includes at least one of the following: the interval between the initial time and the current time that the defrosting condition is met is greater than or equal to a preset duration; the temperature rise of the liquid in the heat exchange module from the initial time to the current time is greater than or equal to a preset temperature. In other embodiments, the first preset condition may also include the duration for which the flow regulation module maintains the current operating parameters after the liquid flow rate into the heat exchange module decreases, etc.

[0089] During the defrosting mode of the first heat exchanger in the operation of the refrigerant circulation device, the second heat exchanger can be in either an evaporation or condensation state.

[0090] In this embodiment, both the first and second heat exchangers are in a heat-releasing state during defrosting mode operation. During the defrosting process of the first heat exchanger, the second heat exchanger can maintain heat supply to the liquid in the storage device. The throttling device includes an electronic expansion valve, which can control the opening of the electronic expansion valve to increase to the defrosting opening, thereby increasing the temperature of the refrigerant flowing into the first heat exchanger and providing heat for defrosting the first heat exchanger. In this embodiment, the throttling device is in a non-throttling state when operating at the defrosting opening. The defrosting opening can be a preset fixed opening (e.g., the maximum opening), or it can be an opening determined based on the actual operating conditions of the system, such as the frosting state of the first heat exchanger and the liquid temperature in the storage device.

[0091] In addition to increasing the opening of the electronic expansion valve to the defrost opening, the defrost mode may also include: controlling the flow regulation module to adjust the liquid flow rate from the liquid storage device into the heat exchange module to the defrost flow rate, and / or controlling the compressor to operate at the defrost frequency. The defrost flow rate here can be a preset fixed flow rate, or a flow rate determined based on the temperature difference between the current liquid temperature in the liquid storage device and the user-set temperature. The defrost flow rate is less than or equal to the liquid flow rate from the liquid storage device into the heat exchange module before the defrost conditions are met; the defrost frequency is less than, equal to, or greater than the compressor's operating frequency before the defrost conditions are met.

[0092] This embodiment provides a control method for a heat pump system. When the second heat exchanger is in a condensing state and heating the liquid in the storage device, and the first heat exchanger is in an evaporating state and there is a risk of frosting, the defrosting operation is not started immediately. Instead, the flow rate of the liquid flowing from the storage device into the heat exchange module is reduced by the flow regulation module to increase the temperature of the second heat exchanger. This can store heat for the subsequent defrosting process, which is beneficial to improving defrosting efficiency and reducing system energy consumption during the defrosting process, thereby improving defrosting efficiency and system energy efficiency.

[0093] In one feasible implementation, the step of controlling the flow regulation module to reduce the liquid flow rate from the liquid storage device into the heat exchange module includes: controlling the flow regulation module to reduce the liquid flow rate from the liquid storage device into the heat exchange module to a target flow rate; wherein the target flow rate is negatively correlated with the frost thickness of the first heat exchanger.

[0094] The target flow rate can be determined based on characteristic parameters representing the frost thickness of the first heat exchanger. These characteristic parameters may include at least one of the following: the temperature of the first heat exchanger, the current of the fan corresponding to the first heat exchanger, the air resistance difference before and after heat exchange in the first heat exchanger, the ambient temperature of the environment where the first heat exchanger is located, the deviation between the control speed and the actual speed of the fan corresponding to the first heat exchanger, etc.

[0095] In this embodiment, under the condition that defrosting conditions are met, the target flow rate is determined based on the temperature of the first heat exchanger, and the target flow rate is positively correlated with the temperature of the first heat exchanger. The lower the temperature of the first heat exchanger, the greater the frost thickness, and the smaller the corresponding target flow rate. The target flow rate can be determined based on the temperature range in which the temperature of the first heat exchanger falls, or the target flow rate can be calculated by substituting the temperature of the first heat exchanger into a preset formula.

[0096] Based on any of the above embodiments, in the second embodiment of this application, the same or similar content as the above embodiments can be referred to the above description, and will not be repeated hereafter. Based on this, please refer to... Figure 5 Step S30 includes steps S31 to S33:

[0097] Step S31: Under the condition that the first preset condition is met, control the flow regulation module to adjust the flow rate of the liquid flowing from the liquid storage device into the heat exchange module to the defrosting flow rate.

[0098] The defrosting flow rate is less than or equal to the target flow rate mentioned above.

[0099] During step S31, the electronic expansion valve can maintain its current opening and the compressor can maintain its current frequency.

[0100] Step S32: Under the condition of satisfying the second preset condition, control the compressor to operate at the defrosting frequency, and control the electronic expansion valve to increase to the transition opening, wherein the transition opening is less than the defrosting opening.

[0101] The second preset condition may include a cumulative duration reaching a first preset duration, wherein the cumulative duration is counted from the start moment when the refrigerant circulation device meets the defrosting conditions. Alternatively, the second preset condition may include a first timing duration reaching a second duration, wherein the first timing duration is counted from the moment the first preset condition is met.

[0102] The transition opening can be a preset fixed opening, or it can be determined based on the initial opening of the electronic expansion valve when the defrosting conditions are met and / or the temperature of the second heat exchanger and / or the flow difference between the target flow rate and the defrosting flow rate when the second preset conditions are met.

[0103] Step S33: Under the condition that the third preset condition is met, control the electronic expansion valve to increase its opening to the defrosting opening.

[0104] The third preset condition may include a cumulative duration reaching a second preset duration, wherein the cumulative duration is counted from the start moment when the refrigerant circulation device meets the defrosting start condition, and the second preset duration is longer than the first preset duration. Alternatively, the third preset condition may include a second timing duration reaching a third duration, where the second timing duration starts counting from the moment the second preset condition is met. Alternatively, the third preset condition may include the temperature of the second heat exchanger being greater than a preset temperature and the temperature change rate of the indoor heat exchanger being less than a preset value, etc.

[0105] After step S33, the compressor maintains the defrosting frequency, the flow regulation module maintains the flow rate from the liquid storage device into the heat exchange module at the defrosting flow rate, and the throttling device maintains the defrosting opening until the defrosting exit condition is met. The defrosting exit condition indicates that the defrosting risk of the first heat exchanger has been eliminated.

[0106] In this embodiment, the regulation of the liquid flow rate into the heat exchange module, the regulation of the compressor frequency, and the adjustment of the opening of the electronic expansion valve work together to ensure that the defrosting heat and the heating amount of the liquid storage device reach the target ratio, guaranteeing defrosting efficiency and reducing large temperature fluctuations of the liquid in the liquid storage device. Specifically, first controlling the liquid in the liquid storage device to flow into the heat exchange module at a defrosting flow rate until a stable state is reached, and then further adjusting the compressor operating frequency and the opening of the electronic expansion valve, facilitates the precise distribution of heat supplied by the liquid storage device and defrosting heat from the first heat exchanger, achieving an effective balance between defrosting and heating of the liquid storage device.

[0107] After the refrigerant regulation module, compressor, and throttling device all operate with the corresponding defrosting parameters, when the refrigerant circulation device meets the defrosting end conditions, each component can be controlled to return to the operating parameters before the defrosting conditions were met. In particular, during the process of the compressor and throttling device returning to the corresponding operating parameters in the heating mode, the corresponding operating parameters are adjusted in a stepwise manner.

[0108] In other embodiments, after step S33, the actual ratio of defrosting heat to the heat supplied by the liquid storage device can be determined based on the temperature difference between the temperature of the first heat exchanger and the liquid temperature in the liquid storage device and the user-set temperature. Based on the deviation between the actual ratio and the target ratio, the compressor is controlled to adjust its operating frequency and / or the flow rate regulation module is controlled to adjust the flow rate of the liquid flowing from the liquid storage device into the heat exchange module.

[0109] In one feasible implementation, the flow area parameters of the throttling device, the refrigerant flow rate at the inlet side of the throttling device, and the cylinder volume parameters of the compressor are obtained; the frequency range of the compressor is determined based on the flow area parameters, the refrigerant flow rate, and the volume parameters; and the defrosting frequency is determined within the frequency range.

[0110] The flow area parameter is a characteristic parameter representing the flow area of ​​the throttling device when it is operating at the defrosting opening. The flow area parameter includes at least one of the following: flow area, throttling device diameter, defrosting opening, pressure difference between the inlet and outlet of the throttling device, etc.

[0111] The refrigerant flow rate can be detected by a flow rate sensor located on the inlet side of the throttling device.

[0112] Volumetric parameters are characteristic parameters that represent the cylinder volume. Volumetric parameters may include volume, cylinder bore, cylinder length, width, and height, etc.

[0113] In this embodiment, the upper frequency limit and / or lower frequency limit are determined based on the volume parameters, flow area parameters, and refrigerant flow rate, and the range corresponding to the upper frequency limit and / or lower frequency limit is taken as the frequency range.

[0114] In this embodiment, the above method can ensure both indoor thermal comfort and outdoor defrosting effect while improving system energy efficiency.

[0115] In one feasible implementation, the step of controlling the refrigerant circulation device to defrost the first heat exchanger includes:

[0116] Based on the target heat relationship, the electronic expansion valve is controlled to increase its opening to the defrosting opening, the flow regulation module is controlled to adjust the liquid flow rate from the liquid storage device into the heat exchange module to the defrosting flow rate, and the compressor is controlled to operate at the defrosting frequency;

[0117] The target heat relationship includes defrosting heat being greater than or equal to the heat supplied by the second heat exchanger, and / or the target heat relationship includes the difference between defrosting heat and the heat supplied by the second heat exchanger being less than a preset heat.

[0118] The defrosting heat is the heat released by the first heat exchanger for defrosting. The heat supplied by the second heat exchanger is the heat provided by the second heat exchanger to the liquid in the storage device during the defrosting process of the first heat exchanger.

[0119] The target heat ratio is the ratio between the defrosting heat and the heat supplied by the second heat exchanger, ensuring that the first heat exchanger completes defrosting within a preset time and the indoor temperature fluctuation is less than the preset temperature value. For example, the preset temperature value here is 3℃. The preset time ranges from [130s, 180s]. The target ratio ranges from [1, 2], for example, a target ratio of 1.2. Based on this, it can be ensured that both the defrosting requirement and the heating requirement of the liquid storage device are met simultaneously.

[0120] In this embodiment, the control methods for controlling the operation of the above-mentioned components according to the target heat relationship include, but are not limited to, at least one of the following: control of the opening change process (continuously increasing the opening or increasing the opening in stages, setting the intermediate opening when increasing the opening in stages, the target rate of opening change, etc.), setting the defrosting opening, and the timing of increasing the opening; control of the frequency change process (continuously decreasing the frequency or decreasing the frequency in stages, setting the intermediate frequency when decreasing the frequency in stages, the target rate of frequency change, etc.), setting the defrosting frequency, and the timing of decreasing the frequency; control of the liquid flow rate change process flowing into the heat exchange module (continuously decreasing the flow rate or decreasing the flow rate in stages, setting the intermediate flow rate when decreasing the flow rate in stages, the target rate of flow rate change, etc.), setting the defrosting flow rate, and the timing of decreasing the flow rate, etc. For example, based on the execution of the above steps S31 to S33, the defrosting heat and the heat supplied by the second heat exchanger can meet the target heat relationship.

[0121] In this embodiment, the above method helps to further improve the accuracy of the heat supply and defrosting heat distribution of the second heat exchanger, and effectively balance the defrosting effect and the heating demand of the liquid storage device.

[0122] Based on any of the above embodiments, in the second embodiment of this application, the same or similar content as the above embodiments can be referred to the above description, and will not be repeated hereafter. Based on this, please refer to... Figure 6 Step S20 includes step S21:

[0123] Step S21: When the defrosting conditions are met, control the compressor to operate at a lower frequency and control the flow regulation module to reduce the liquid flow rate from the liquid storage device into the heat exchange module, so that the temperature of the second heat exchanger increases and the temperature of the second heat exchanger after the increase is lower than the preset temperature.

[0124] The preset temperature is the maximum temperature of the second heat exchanger that is allowed by the reliability of the refrigerant circulation device. The compressor must be stopped when the temperature of the second heat exchanger reaches the preset temperature.

[0125] The reduced frequency of the compressor here is the transition frequency. The transition frequency is lower than the initial frequency of the compressor when the defrosting conditions are met, and the transition frequency is greater than or equal to the aforementioned defrosting frequency. The compressor can continuously reduce its frequency from the heating frequency to the transition frequency at the target reduction rate, or it can reduce its frequency from the heating frequency to the transition frequency in stages.

[0126] During the execution of step S20, the electronic expansion valve maintains its initial opening when the defrosting conditions are met, that is, the electronic expansion valve remains in a throttling state.

[0127] During step S20, the fan maintains the initial speed that meets the defrosting conditions, that is, the fan maintains the current speed.

[0128] In this embodiment, the flow rate of the liquid flowing into the heat exchange module decreases while the compressor operates at a reduced frequency to a transitional frequency. In other implementations, the compressor may also first operate at a reduced frequency to a transitional frequency for a period of time before controlling the flow regulation module to reduce the flow rate of the liquid flowing from the storage device into the heat exchange module.

[0129] In this embodiment, by reducing the liquid flow rate into the storage device through the flow regulation module, heat is stored for the subsequent defrosting process. At the same time, by reducing the frequency of the compressor, the temperature of the second heat exchanger is prevented from being too high and triggering the compressor protection shutdown. This improves defrosting efficiency, system energy efficiency, and the operational stability of the refrigerant circulation device.

[0130] In one feasible implementation, the compressor's frequency reduction ratio is greater than the reduction ratio of the liquid flow rate into the heat exchange module.

[0131] The frequency reduction ratio is the percentage of the compressor's frequency reduction relative to its heating frequency before defrosting conditions are met. The reduction percentage is the percentage of the reduction in liquid flowing into the heat exchange module relative to the initial flow rate of liquid flowing into the heat exchange module before defrosting conditions are met. The transition frequency is determined based on the heating frequency and the frequency reduction ratio; the target flow rate after reducing the liquid flow into the heat exchange module is determined based on the initial flow rate and the reduction percentage. Specifically, in determining the target flow rate based on the temperature of the first heat exchanger, an upper limit for the flow rate can be determined based on the initial flow rate and the reduction percentage, and the target flow rate can be determined within a flow range that is less than or equal to the upper limit based on the temperature of the first heat exchanger.

[0132] In this embodiment, the reduction ratio is obtained by lowering the frequency reduction ratio according to the preset adjustment parameters.

[0133] In this embodiment, the above method helps to increase the heat storage before defrosting, thereby further improving defrosting efficiency and system energy efficiency.

[0134] It should be noted that the above examples are only for understanding this application and do not constitute a limitation on the control method of the heat pump system of this application. Any simple modifications based on this technical concept are within the protection scope of this application.

[0135] This application provides a computer-readable storage medium having computer-readable program instructions (i.e., a computer program) stored thereon, the computer-readable program instructions being used to execute the control method of the heat pump system in the above embodiments.

[0136] The computer-readable storage medium provided in this application may be, for example, a USB flash drive, but is not limited to, electrical, magnetic, optical, electromagnetic, infrared, or semiconductor systems, devices, or any combination thereof. More specific examples of computer-readable storage media may include, but are not limited to: electrical connections having one or more wires, portable computer disks, hard disks, random access memory (RAM), read-only memory (ROM), erasable programmable read-only memory (EPROM or flash memory), optical fiber, portable compact disk read-only memory (CD-ROM), optical storage devices, magnetic storage devices, or any suitable combination thereof. In this embodiment, the computer-readable storage medium may be any tangible medium containing or storing a program that can be used by or in conjunction with an instruction execution system, system, or device. The program code contained on the computer-readable storage medium may be transmitted using any suitable medium, including but not limited to: wires, optical cables, RF (Radio Frequency), etc., or any suitable combination thereof.

[0137] The aforementioned computer-readable storage medium may be included in the heat pump system or may exist independently without being assembled into the heat pump system.

[0138] The aforementioned computer-readable storage medium carries one or more programs that, when executed by the heat pump system, cause the heat pump system to perform the following processes: controlling the operation of the refrigerant circulation device to put the first heat exchanger in an evaporating state and the second heat exchanger in a condensing state; controlling the operation of the flow regulation module to allow liquid in the liquid storage device to flow into the heat exchange module; when defrosting conditions are met, controlling the flow regulation module to reduce the liquid flow rate from the liquid storage device into the heat exchange module; and when a first preset condition is met, controlling the operation of the refrigerant circulation device to defrost the first heat exchanger; wherein, the defrosting condition indicates that the first heat exchanger is at risk of frosting.

[0139] Computer program code for performing the operations of this application can be written in one or more programming languages ​​or a combination thereof, including object-oriented programming languages ​​such as Java, Smalltalk, and C++, and conventional procedural programming languages ​​such as the "C" language or similar programming languages. The program code can be executed entirely on the user's computer, partially on the user's computer, as a standalone software package, partially on the user's computer and partially on a remote computer, or entirely on a remote computer or server. In cases involving remote computers, the remote computer can be connected to the user's computer via any type of network—including a Local Area Network (LAN) or a Wide Area Network (WAN)—or can be connected to an external computer (e.g., via the Internet using an Internet service provider).

[0140] The readable storage medium provided in this application is a computer-readable storage medium that stores computer-readable program instructions (i.e., a computer program) for executing the control method of the above-described heat pump system, which can solve the technical problem of how to improve defrosting efficiency and system energy efficiency. Compared with the prior art, the beneficial effects of the computer-readable storage medium provided in this application are the same as the beneficial effects of the control method of the heat pump system provided in the above embodiments, and will not be repeated here.

[0141] The flowcharts and block diagrams in the accompanying drawings illustrate the architecture, functionality, and operation of possible implementations of systems, methods, and computer program products according to various embodiments of this application. In this regard, each block in a flowchart or block diagram may represent a module, segment, or portion of code containing one or more executable instructions for implementing a specified logical function. It should also be noted that in some alternative implementations, the functions indicated in the blocks may occur in a different order than those indicated in the drawings. For example, two consecutively indicated blocks may actually be executed substantially in parallel, and they may sometimes be executed in reverse order, depending on the functions involved. It should also be noted that each block in the block diagrams and / or flowcharts, and combinations of blocks in the block diagrams and / or flowcharts, can be implemented using a dedicated hardware-based system that performs the specified function or operation, or using a combination of dedicated hardware and computer instructions.

[0142] It should be understood that the various parts disclosed in this application can be implemented using hardware, software, firmware, or a combination thereof. Modules described in the embodiments of this application can be implemented in software or hardware. The names of modules do not necessarily limit the specific unit itself. In the description of the above embodiments, specific features, structures, materials, or characteristics can be combined in any suitable manner in one or more embodiments or examples.

[0143] The above descriptions are merely some embodiments of this application and do not limit the patent scope of this application. Any equivalent structural transformations made based on the technical concept of this application and the content of this specification and drawings, or direct / indirect applications in other related technical fields, are included within the patent protection scope of this application. Therefore, the protection scope of this application should be determined by the scope of the claims.

Claims

1. A control method for a heat pump system, characterized in that, The heat pump system includes a refrigerant circulation device, a heat exchange module, and a liquid storage device. The refrigerant circulation device includes a compressor and a first heat exchanger, a throttling device, and a second heat exchanger connected in sequence. The second heat exchanger is connected to the heat exchange module for heat exchange. The heat exchange module is connected to the liquid storage device. A flow regulation module is installed in the connecting pipeline between the heat exchange module and the liquid storage device. The method includes: The refrigerant circulation device is controlled to operate so that the first heat exchanger is in an evaporation state and the second heat exchanger is in a condensation state, and the flow regulation module is controlled to operate so that the liquid in the liquid storage device flows into the heat exchange module; When defrosting conditions are met, the flow regulation module is controlled to reduce the liquid flow rate from the liquid storage device into the heat exchange module; Under the condition that the first preset condition is met, the refrigerant circulation device is controlled to operate in order to defrost the first heat exchanger; The defrosting conditions indicate that the first heat exchanger is at risk of frosting.

2. The method as described in claim 1, characterized in that, The step of controlling the flow regulation module to reduce the liquid flow rate from the liquid storage device into the heat exchange module includes: The flow regulation module is controlled to reduce the flow rate of liquid flowing from the liquid storage device into the heat exchange module to the target flow rate; The target flow rate is negatively correlated with the frost thickness of the first heat exchanger.

3. The method as described in claim 2, characterized in that, Before the step of controlling the flow regulation module to reduce the liquid flow rate from the liquid storage device into the heat exchange module to the target flow rate, the method further includes: Under the condition that defrosting is met, the target flow rate is determined based on the temperature of the first heat exchanger, and the target flow rate is positively correlated with the temperature of the first heat exchanger.

4. The method as described in claim 1, characterized in that, The first preset condition includes at least one of the following: The time interval between the initial time when the defrosting conditions are met and the current time is greater than or equal to a preset time. The temperature rise of the liquid in the heat exchange module from the initial moment to the current moment is greater than or equal to the preset temperature.

5. The method as described in claim 1, characterized in that, The throttling device includes an electronic expansion valve, and the step of controlling the operation of the refrigerant circulation device to defrost the first heat exchanger includes: Control the electronic expansion valve to increase its opening to the defrosting opening.

6. The method as described in claim 5, characterized in that, The step of controlling the operation of the refrigerant circulation device to defrost the first heat exchanger further includes: The flow regulation module is controlled to adjust the liquid flow rate from the liquid storage device into the heat exchange module to the defrosting flow rate, and / or the compressor is controlled to operate at the defrosting frequency.

7. The method as described in claim 6, characterized in that, The step of controlling the refrigerant circulation device to defrost the first heat exchanger when the first preset condition is met includes: Under the condition that the first preset condition is met, the flow regulation module is controlled to adjust the flow rate of the liquid flowing from the liquid storage device into the heat exchange module to the defrosting flow rate; Under the condition that the second preset condition is met, the compressor is controlled to operate at the defrosting frequency, and the electronic expansion valve is controlled to increase to the transition opening. Under the condition that the third preset condition is met, the electronic expansion valve is controlled to increase its opening to the defrosting opening. Wherein, the transition opening degree is less than the defrosting opening degree.

8. The method as described in claim 6, characterized in that, The step of controlling the operation of the refrigerant circulation device to defrost the first heat exchanger includes: Based on the target heat relationship, the electronic expansion valve is controlled to increase its opening to the defrosting opening, the flow regulation module is controlled to adjust the liquid flow rate from the liquid storage device into the heat exchange module to the defrosting flow rate, and the compressor is controlled to operate at the defrosting frequency; The target heat relationship includes defrosting heat being greater than or equal to the heat supplied by the second heat exchanger, and / or the target heat relationship includes the difference between defrosting heat and the heat supplied by the second heat exchanger being less than a preset heat.

9. The method according to any one of claims 1 to 8, characterized in that, The step of controlling the flow regulation module to reduce the liquid flow rate from the liquid storage device into the heat exchange module when the defrosting conditions are met includes: When the defrosting conditions are met, the compressor is controlled to operate at a reduced frequency and the flow regulation module is controlled to reduce the liquid flow rate from the liquid storage device into the heat exchange module, so that the temperature of the second heat exchanger increases and the increased temperature of the second heat exchanger is lower than the preset temperature.

10. The method as described in claim 9, characterized in that, The compressor's frequency reduction ratio is greater than the reduction ratio of the liquid flow rate into the heat exchange module.

11. A heat pump system, characterized in that, The heat pump system includes a control device, a refrigerant circulation device, a heat exchange module, and a liquid storage device. The refrigerant circulation device includes a compressor and a first heat exchanger, a throttling device, and a second heat exchanger connected in sequence. The second heat exchanger is heat-exchange connected to the heat exchange module. The heat exchange module is connected to the liquid storage device. A flow regulation module is provided in the connecting pipeline between the heat exchange module and the liquid storage device. The refrigerant circulation device is communicatively connected to the control device, which includes a memory, a processor, and a computer program stored in the memory and executable on the processor. The computer program is configured to implement the steps of the control method for the heat pump system as described in any one of claims 1 to 10.

12. A storage medium, characterized in that, The storage medium is a computer-readable storage medium, and a computer program is stored on the storage medium. When the computer program is executed by a processor, it implements the steps of the control method for the heat pump system as described in any one of claims 1 to 10.

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