Method and device for controlling heat pump unit and heat pump unit

Abstract

The invention relates to the technical field of heat pump units, and discloses a method for controlling a heat pump unit, which comprises the following steps: acquiring fluid pressure of a preset position under the condition that the heat pump unit is in refrigeration operation; the preset position is located between the hollow cavity and the second heat exchanger; the opening and closing state of the switch structure is controlled according to the fluid pressure so as to control the amount of fluid flowing from the hollow cavity to the second cavity. By detecting the pressure of the fluid at the preset position, namely the pressure of the fluid before the fluid enters the liquid storage device, and controlling the opening and closing state of the switch structure according to the pressure of the fluid, the fluid amount of the heat pump unit can be self-adjusted, so that the fluid amount participating in fluid circulation of the heat pump unit in the liquid storage device is adjusted; the control accuracy of the fluid circulation amount in the refrigeration working condition is improved, and therefore the overall operation efficiency and stability of the heat pump unit are improved. The invention further discloses a device for controlling the heat pump unit and the heat pump unit.

Description

Technical Field

[0001] The present application relates to the technical field of heat pump units, for example, to a method and device for controlling a heat pump unit, and a heat pump unit. Background Art

[0002] Air source heat pump units have heating functions in the heating season and cooling functions in the cooling season. During heating operation, the heat exchanger serving as the condenser is located on the user side, while the heat exchanger serving as the evaporator is located on the air side. During cooling operation, the situation is reversed, with the heat exchanger serving as the condenser located on the air side and the heat exchanger serving as the evaporator located on the user side. Due to space utilization and cost limitations, heat pump units cannot have two heat exchangers with the same heat exchange area. This results in a situation where, when a certain amount of refrigerant is injected into the same heat pump unit, the amount of refrigerant circulating during heating operation will be less than the amount circulating during cooling operation, making it difficult for the heat pump unit to achieve the desired results in both heating and cooling operations.

[0003] To improve the heating and cooling performance of heat pump units, related technologies include a liquid reservoir in the unit. During heating operation, the amount of refrigerant circulating is low, and the excess refrigerant in the heat pump unit is stored in the reservoir. During cooling operation, the amount of refrigerant circulating is high, and the refrigerant stored in the reservoir also participates in the refrigeration cycle.

[0004] In the process of implementing the embodiments of the present disclosure, it was found that there are at least the following problems in the related technology: when the air source heat pump unit is in refrigeration operation, the amount of refrigerant participating in the refrigeration cycle in the liquid reservoir is fixed. In the event of sudden changes in the operating conditions and changes in the line control state, the refrigeration effect of the heat pump unit is affected.

[0005] It should be noted that the information disclosed in the above background technology section is only used to enhance the understanding of the background of this application, and therefore may include information that does not constitute prior art known to ordinary technicians in this field. Summary of the Invention

[0006] In order to provide a basic understanding of some aspects of the disclosed embodiments, a brief summary is given below. The summary is not an extensive review, nor is it intended to identify key / critical elements or delineate the scope of protection of these embodiments, but rather serves as a prelude to the detailed description that follows.

[0007] The embodiments of the present disclosure provide a method, device and heat pump unit for controlling a heat pump unit, so as to perform self-regulation of the refrigerant through a liquid storage device in a cooling mode, so as to respond promptly to changes in the operating conditions of the heat pump unit and improve the stability of the operation of the heat pump unit.

[0008] In some embodiments, a heat pump unit includes a liquid reservoir, a first heat exchanger located on the user side, and a second heat exchanger located on the air side; the liquid reservoir includes a first cavity, a second cavity having a common first cavity wall with the first cavity, a buoyancy lifting structure, and a switch structure; the second cavity is connected to the second heat exchanger and the first heat exchanger respectively; the buoyancy lifting structure is arranged in the first cavity, and has a hollow cavity inside thereof that is connected to the second heat exchanger, so that the fluid flowing through the second heat exchanger can flow into the hollow cavity; the switch structure is arranged between the hollow cavity and the second cavity, and by controlling the switch structure to be in an open state or a closed state, the fluid in the hollow cavity can flow into the second cavity in a unidirectional manner or the fluid in the hollow cavity can be prohibited from flowing into the second cavity; a method for controlling the heat pump unit includes: when the heat pump unit is in cooling operation, obtaining a fluid pressure at a preset position; wherein the preset position is between the hollow cavity and the second heat exchanger; controlling the opening and closing state of the switch structure according to the fluid pressure to control the amount of fluid flowing from the hollow cavity to the second cavity.

[0009] Optionally, the opening and closing state of the switch structure is controlled according to the fluid pressure, including: when the fluid pressure is less than a preset pressure, controlling the switch structure to be in an open state so that the fluid in the hollow cavity flows unidirectionally into the second cavity; and / or, when the fluid pressure is greater than the preset pressure, controlling the switch structure to be in a closed state to prohibit the fluid in the hollow cavity from flowing into the second cavity; and / or, when the fluid pressure is equal to the preset pressure, obtaining the current opening and closing state of the switch structure, and controlling the switch structure to be in the current opening and closing state.

[0010] Optionally, the heat pump unit further includes a compressor; the preset pressure is determined as follows: obtaining the operating frequency of the compressor of the heat pump unit; obtaining the liquid pipe temperature of the first heat exchanger; and determining the preset pressure based on the operating frequency of the compressor and the liquid pipe temperature of the first heat exchanger.

[0011] Optionally, the preset pressure is determined according to the operating frequency of the compressor and the liquid pipe temperature of the first heat exchanger, including: determining the refrigerant saturation temperature according to the operating frequency of the compressor and the liquid pipe temperature of the first heat exchanger; and determining the preset pressure corresponding to the refrigerant saturation temperature according to a preset first corresponding relationship.

[0012] Optionally, the preset pressure is determined as follows: obtain the ambient temperature of the air side of the heat pump unit; obtain the outlet water temperature of the user side of the heat pump unit; and determine the preset pressure based on the ambient temperature of the air side and the outlet water temperature of the user side.

[0013] Optionally, determining the preset pressure according to the ambient temperature on the air side and the outlet water temperature on the user side includes: determining the preset pressure corresponding to the ambient temperature on the air side and the outlet water temperature on the user side according to a preset second corresponding relationship.

[0014] Optionally, the buoyancy lifting structure is provided with a liquid outlet connected to the hollow cavity; the switch structure includes a plurality of one-way guide holes arranged along the height direction of the first cavity wall. When the fluid flowing through the second heat exchanger flows into the hollow cavity of the buoyancy lifting structure, the buoyancy lifting structure can move up and down in the first cavity under the buoyancy provided by the fluid inside the first cavity, and when the liquid outlet of the buoyancy lifting structure corresponds to the one-way guide hole, they can be tangent to each other and make the one-way guide hole unidirectional so that the fluid in the hollow cavity flows to the second cavity; the opening and closing state of the switch structure is controlled in the following manner: the liquid outlet of the buoyancy lifting structure is controlled to be in a corresponding state with the one-way guide hole, so that the switch structure is in an open state; and / or, the liquid outlet of the buoyancy lifting structure is controlled to be in a non-corresponding state with the one-way guide hole, so that the switch structure is in a closed state.

[0015] Optionally, the first cavity is connected to the second heat exchanger; the heat pump unit also includes a solenoid valve, which is arranged on the pipeline between the first cavity and the second heat exchanger; wherein: the solenoid valve is controlled to be in an open state so that the liquid outlet of the buoyancy lifting structure is in a corresponding state with multiple one-way guide holes in sequence; and / or, the solenoid valve is controlled to be in a closed state to prohibit the fluid flowing through the second heat exchanger from flowing into the first cavity, so that the liquid outlet of the buoyancy lifting structure and the one-way guide holes are in a non-corresponding state.

[0016] In some embodiments, the apparatus for controlling a heat pump unit includes a processor and a memory storing program instructions, and the processor is configured to execute the above-described method for controlling a heat pump unit when running the program instructions.

[0017] In some embodiments, the heat pump unit includes: a heat pump unit body; a first heat exchanger, which is arranged in the heat pump unit body and located on the user side; a second heat exchanger, which is arranged in the heat pump unit body and located on the air side; a liquid reservoir, which is arranged in the heat pump unit body, including a first cavity, a second cavity having a common first cavity wall with the first cavity, a buoyancy lifting structure and a switch structure; the second cavity is connected to the second heat exchanger and the first heat exchanger respectively; the buoyancy lifting structure is arranged in the first cavity, and has a hollow cavity connected to the second heat exchanger inside, so that the fluid flowing through the second heat exchanger can flow into the hollow cavity; the switch structure is arranged between the hollow cavity and the second cavity, and by controlling the switch structure to be in an open state or a closed state, the fluid in the hollow cavity can flow into the second cavity in one direction or the fluid in the hollow cavity is prohibited from flowing into the second cavity; the device for controlling the heat pump unit as described above is installed on the heat pump unit body.

[0018] The method, device, and heat pump unit for controlling a heat pump unit provided by the embodiments of the present disclosure can achieve the following technical effects:

[0019] During the cooling operation of the heat pump unit, the fluid flows through the second heat exchanger, the liquid reservoir and the first heat exchanger in sequence. Since the second heat exchanger is connected to the second cavity and the hollow cavity respectively, part of the fluid flowing through the second heat exchanger flows into the hollow cavity of the buoyancy lifting structure, and part flows into the second cavity. Since the hollow cavity and the second cavity are controlled by the switch structure, the passage between the hollow cavity and the second cavity is connected, or the passage between the hollow cavity and the second cavity is cut off. In this way, by detecting the fluid pressure at a preset position, that is, the fluid pressure before entering the liquid reservoir, and controlling the opening and closing state of the switch structure according to the fluid pressure, the fluid amount of the heat pump unit can be self-regulated, thereby adjusting the amount of fluid in the liquid reservoir participating in the fluid circulation of the heat pump unit, improving the control accuracy of the fluid circulation amount in the refrigeration condition, and thus improving the overall operation efficiency and stability of the heat pump unit.

[0020] The above general description and the following description are exemplary and explanatory only and are not intended to limit the present application. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] One or more embodiments are exemplarily described by corresponding drawings. These exemplary descriptions and drawings do not limit the embodiments. Elements with the same reference numerals in the drawings are shown as similar elements. The drawings do not constitute a scale limitation. In addition,

[0022] Figure 1 is a structural schematic diagram of a liquid reservoir provided by an embodiment of the present disclosure;

[0023] Figure 2 is a structural schematic diagram of a heat pump unit provided by an embodiment of the present disclosure;

[0024] Figure 3 is a schematic diagram of a method for controlling a heat pump unit provided by an embodiment of the present disclosure;

[0025] Figure 4 is a schematic diagram of another method for controlling a heat pump unit provided by an embodiment of the present disclosure;

[0026] Figure 5 is a schematic diagram of a device for controlling a heat pump unit provided by an embodiment of the present disclosure;

[0027] Figure 6 Schematic diagram of another device for controlling a heat pump unit provided by an embodiment of the present disclosure.

[0028] Reference numerals:

[0029] 1. Liquid storage tank; 2. Heat pump unit;

[0030] 10. First cavity; 101. Ventilation structure;

[0031] 20. Second cavity;

[0032] 30. Buoyancy lifting structure;

[0033] 40. First liquid inlet pipe;

[0034] 50. Second liquid inlet pipe;

[0035] 60. One-way guide hole;

[0036] 701, first heat exchanger; 702, second heat exchanger; 703, compressor; 704, four-way valve;

[0037] 80. First refrigerant pipe;

[0038] 90. Second refrigerant pipe;

[0039] 100, first throttling device;

[0040] 110. Second throttling device;

[0041] 120, solenoid valve;

[0042] 130, flow valve;

[0043] 140. Pressure sensor;

[0044] 150, piston assembly; 1501, upper cavity; 1502, lower cavity;

[0045] 160, valve body;

[0046] 200(300), a device for controlling a heat pump unit;

[0047] 600, processor; 601, memory; 602, communication interface; 603, bus. DETAILED DESCRIPTION

[0048] In order to be able to understand the features and technical content of the embodiments of the present disclosure in more detail, the implementation of the embodiments of the present disclosure is described in detail below in conjunction with the accompanying drawings. The accompanying drawings are for reference only and are not used to limit the embodiments of the present disclosure. In the following technical description, for the sake of convenience of explanation, a full understanding of the disclosed embodiments is provided through multiple details. However, one or more embodiments can still be implemented without these details. In other cases, to simplify the drawings, well-known structures and devices can be simplified for display.

[0049] In the description and claims of the embodiments of the present disclosure, as well as in the accompanying drawings, the terms "first," "second," and the like are used to distinguish similar items and are not necessarily used to describe a particular order or precedence. It should be understood that the terms used in this manner are interchangeable where appropriate to describe the embodiments of the present disclosure herein. In addition, the terms "including," "having," and any variations thereof are intended to cover non-exclusive inclusions.

[0050] Unless otherwise stated, the term "plurality" means two or more.

[0051] In the embodiment of the present disclosure, the character " / " indicates that the preceding and following objects are in an "or" relationship. For example, A / B means: A or B.

[0052] The term "and / or" describes an association between objects, indicating that three relationships can exist. For example, A and / or B means: A or B, or A and B.

[0053] The term "correspondence" may refer to an association relationship or a binding relationship. The correspondence between A and B means that there is an association relationship or a binding relationship between A and B.

[0054] It should be noted that, in the absence of conflict, the embodiments and features in the embodiments of the present disclosure can be combined with each other.

[0055] The present disclosure provides a method for controlling a heat pump unit, which is applied to a heat pump unit 2. Figure 1 and Figure 2 As shown, the heat pump unit 2 includes a liquid reservoir 1, a first heat exchanger 701 located on the user side, and a second heat exchanger 702 located on the air side. The liquid reservoir 1 includes a first cavity 10, a second cavity 20 having a common first cavity wall with the first cavity, a buoyancy lifting structure 30, and a switch structure. The second cavity 20 is connected to the second heat exchanger 702 and the first heat exchanger 701, respectively. The buoyancy lifting structure 30 is disposed within the first cavity 10 and has a hollow cavity therein that is connected to the second heat exchanger 702, allowing fluid flowing through the second heat exchanger 702 to flow into the hollow cavity. The switch structure is disposed between the hollow cavity and the second cavity 20. By controlling the switch structure to be in an open or closed state, the fluid in the hollow cavity can flow unidirectionally into the second cavity 20 or be prohibited from flowing into the second cavity 20. In this way, the amount of fluid flowing into the second cavity 20 can be automatically adjusted, thereby controlling the amount of fluid in the liquid reservoir 1 that participates in the fluid circulation of the heat pump unit 2.

[0056] Alternatively, as Figure 1 and Figure 2 As shown, the first cavity 10 is in communication with the second heat exchanger 702 , so that the fluid of the second heat exchanger 702 can flow into the first cavity 10 as needed.

[0057] Alternatively, as Figure 1 As shown, the buoyancy lifting structure 30 is movably disposed in the first cavity, and can move up and down under the buoyancy provided by the first cavity 10 according to the fluid height in the first cavity 10 .

[0058] Alternatively, as Figure 1 As shown, the switch structure includes a plurality of one-way guide holes 60 arranged along the height direction of the first cavity wall to achieve one-way conduction from the first cavity 10 to the second cavity 20.

[0059] Alternatively, as Figure 1 As shown, the buoyancy lifting structure 30 is provided with a liquid outlet connected to the hollow cavity. The liquid outlet of the buoyancy lifting structure 30 corresponds to the vertical position of the one-way guide hole 60. When the fluid flowing through the second heat exchanger 702 flows into the interior of the first cavity 10, the buoyancy lifting structure 30 can float. At the same time, when the fluid flowing through the second heat exchanger 702 flows into the hollow cavity of the buoyancy lifting structure 30, the buoyancy lifting structure 30 can move up and down in the first cavity 10 under the buoyancy provided by the fluid inside the first cavity 10. When the liquid outlet of the buoyancy lifting structure 30 corresponds to the one-way guide hole 60, they can be tangent to each other and make the one-way guide hole 60 unidirectional, so that the fluid in the buoyancy lifting structure 30 flows to the second cavity 20, thereby adjusting the amount of fluid in the second cavity 20.

[0060] It is understood that when the heat pump unit 2 is in heating operation, the first heat exchanger 701 serves as a condenser and the second heat exchanger 702 serves as an evaporator. When the heat pump unit 2 is in cooling operation, the first heat exchanger 701 serves as an evaporator and the second heat exchanger 702 serves as a condenser.

[0061] The fluid flowing through the heat pump unit 2 is refrigerant.

[0062] For example, the number of the plurality of unidirectional flow guide holes 60 may be set to 4, 5, 6, 7, 8, 9 or 10.

[0063] Exemplarily, every two unidirectional air guide holes 60 are arranged at the same height.

[0064] In the disclosed embodiment, the liquid reservoir 1 is divided into an independent first cavity 10 and a second cavity 20. When the heat pump unit 2 is in heating operation, the fluid flows through the first heat exchanger 701, the liquid reservoir 1, and the second heat exchanger 702 in sequence, and is connected to the second heat exchanger 702 on the air side and the first heat exchanger 701 on the user side of the pump unit through the second cavity 20 of the liquid reservoir 1. Therefore, in the heating condition, only the fluid in the second cavity 20 of the liquid reservoir 1 participates in the fluid circulation of the heat pump unit 2. At this time, the liquid reservoir 1 only has a liquid storage function, and the fluid flowing from the second cavity 20 of the liquid reservoir 1 to the second heat exchanger 702 can meet the fluid volume required by the heat pump unit 2. When the heat pump unit 2 is in cooling operation, the fluid flows through the second heat exchanger 702, the liquid reservoir 1 and the first heat exchanger 701 in sequence, and is connected with the second cavity 20, the hollow cavity of the buoyancy lifting structure 30 and the first cavity 10 respectively through the second heat exchanger 702. The first heat exchanger 701 is connected with the second cavity 20, so that part of the fluid flowing out through the second heat exchanger 702 flows into the second cavity 20, part flows into the hollow cavity of the buoyancy lifting structure 30, and part flows into the first cavity 10 as needed. It should be noted that the fluid flowing into the first cavity 10 is used to provide buoyancy for the buoyancy lifting structure 30 to adjust the moving height of the buoyancy lifting structure 30, thereby adjusting whether the buoyancy lifting structure 30 is in a corresponding state with the one-way guide hole 60, and then flows out from the second cavity 20 to the first heat exchanger 701. Since the amount of fluid flowing into the first cavity 10 can control the moving height of the buoyancy lifting structure 30, and a plurality of one-way guide holes 60 are provided on the first cavity wall to ensure that the fluid can only flow from the first cavity 10 to the second cavity 20, when the buoyancy lifting structure 30 moves to different heights, the liquid outlet of the buoyancy lifting structure 30 will be tangent to the corresponding one-way guide hole 60 and the one-way guide hole 60 will be opened, allowing the fluid in the hollow cavity to flow from the first cavity 10 to the second cavity 20 in a timely manner as needed, thereby controlling the amount of fluid in the second cavity 20, and then controlling the amount of fluid in the second cavity 20 participating in the refrigeration cycle of the heat pump unit 2, thereby realizing automatic flow adjustment during the refrigeration operation of the heat pump unit 2. In this way, by automatically controlling the storage and release of the fluid, the problem of changes in the fluid circulation volume of the heat pump unit 2 under different working conditions is effectively solved, and the heat pump unit 2 can store excess fluid through the liquid reservoir 1 in the heating mode and perform fluid self-regulation through the liquid reservoir 1 in the cooling mode, so as to respond in time to changes in the working conditions of the heat pump unit 2 and improve the stability of the operation of the heat pump unit 2.

[0065] In addition, the disclosed embodiment can automatically adjust fluid distribution according to the actual operating conditions of the heat pump unit 2, effectively solving the problem of difficult to accurately control the fluid circulation volume under different operating conditions, and improving the overall operating efficiency and stability of the heat pump unit 2.

[0066] Alternatively, as Figure 1As shown, the first cavity 10 is cylindrical. The buoyancy lifting structure 30 includes a liquid level ball. The liquid level ball has a hollow cavity inside, and the outer wall of the liquid level ball is tangent to the inner wall of the first cavity 10.

[0067] In this disclosed embodiment, the first cavity 10 is cylindrical in design, and the buoyancy lifting structure 30 includes a liquid level ball. Thus, based on the buoyancy characteristics of the liquid level ball, when the liquid level ball is in fluid flowing into the first cavity 10, it can be moved up and down by the buoyancy of the fluid displaced by it. The outer wall of the liquid level ball is arranged tangentially to the inner wall of the first cavity 10, allowing the liquid level ball to change position very smoothly with the changes in the fluid level during its up and down movement, without any stuck phenomenon, thus ensuring the sensitivity and accuracy of fluid flow control. At the same time, as the amount of fluid flowing into the first cavity 10 from the second heat exchanger 702 changes, the liquid level ball moves to different heights accordingly, so that the liquid outlet of the liquid level ball aligns with the corresponding one-way guide hole 60, and the fluid in the hollow cavity flows into the second cavity 20 through the one-way guide hole 60, thereby accurately and in real time adjusting the fluid inventory in the second cavity 20 to meet the fluid circulation requirements during the cooling operation of the entire heat pump unit 2.

[0068] Alternatively, as Figure 1 As shown, the one-way guide hole 60 includes a plurality of through holes arranged along the height direction on the first cavity wall and a one-way valve correspondingly arranged on each through hole to achieve one-way conduction from the first cavity 10 to the second cavity 20.

[0069] It is understandable that when the liquid outlet of the buoyancy lifting structure 30 is in a corresponding state with the through hole, the one-way valve corresponding to the through hole is opened, thereby enabling the fluid to flow from the first cavity 10 to the second cavity 20 through the one-way guide hole 60 .

[0070] In this disclosed embodiment, a through hole and a corresponding one-way valve together constitute a one-way flow guide hole 60. Multiple one-way flow guide holes 60 are located at different heights of the first cavity wall to accommodate the buoyancy lifting structure 30 moving to different heights. That is, when the buoyancy lifting structure 30 (such as a liquid level ball) moves with the change in the fluid level in the first cavity 10, the corresponding one-way flow guide hole 60 will open or close in a timely manner, and the fluid can flow unidirectionally from the hollow cavity to the second cavity 20 as needed. In this way, the fluid entering the second cavity 20 can be finely controlled according to the actual needs and operating conditions of the heat pump unit 2, which is conducive to ensuring the balance and efficiency of the fluid circulation within the heat pump unit 2.

[0071] Alternatively, as Figure 1As shown, a ventilation structure 101 is provided on the housing corresponding to the upper portion of the first cavity 10. Exemplarily, the ventilation structure 101 may be a vent. Thus, the ventilation structure 101 allows air to be exchanged between the inside and outside of the first cavity 10, thereby maintaining pressure equilibrium between the inside and outside of the first cavity 10, thereby avoiding safety hazards caused by excessive pressure or affecting normal system operation due to insufficient pressure.

[0072] Optionally, the liquid reservoir 1 further includes a filter screen, which is arranged on the ventilation structure 101. In this way, it can effectively prevent external dust, impurities, etc. from entering the first cavity 10, preventing them from contaminating the fluid or clogging the pipeline, thereby ensuring the cleanliness and service life of the entire heat pump system.

[0073] Alternatively, as Figure 1 and Figure 2 As shown, the liquid reservoir 1 further includes a first liquid inlet pipe 40 and a second liquid inlet pipe 50. The first end of the first liquid inlet pipe 40 communicates with the hollow cavity of the buoyant lifting structure 30, and the second end communicates with the second heat exchanger 702, allowing refrigerant flowing through the second heat exchanger 702 to flow into the hollow cavity of the buoyant lifting structure 30. The first end of the second liquid inlet pipe 50 communicates with the first cavity 10, and the second end communicates with the second heat exchanger 702. The second liquid inlet pipe 50 can be opened or closed to adjust the amount of fluid flowing into the first cavity 10, thereby controlling the movement position of the buoyant lifting structure 30.

[0074] In this disclosed embodiment, a portion of the fluid flowing out of the second heat exchanger 702 flows into the hollow cavity of the buoyant lifting structure 30 via the first liquid inlet pipe 40. A portion of the fluid flowing out of the second heat exchanger 702 flows into the first cavity 10 as needed via the second liquid inlet pipe 50. Simultaneously, by opening or closing the second liquid inlet pipe 50, the amount of fluid flowing from the second heat exchanger 702 into the first cavity 10 can be precisely controlled, thereby controlling the travel height of the buoyant lifting structure 30 and, in turn, the amount of fluid flowing from the buoyant lifting structure 30 into the second cavity 20.

[0075] It can be understood that in the heating condition of the heat pump unit 2, the first liquid inlet pipe 40 and the second liquid inlet pipe 50 can be turned on or off. Since the fluid of the heat pump unit 2 in the heating condition flows through the first heat exchanger 701, the liquid reservoir 1 and the second heat exchanger 702 in the order of flow. Therefore, at this time, whether the first liquid inlet pipe 40 and the second liquid inlet pipe 50 are turned on or off, it is only necessary to make the liquid outlet of the buoyancy lifting structure 30 and the one-way guide hole 60 in a non-corresponding state, or to make no fluid flow in the first liquid inlet pipe 40 and the second liquid inlet pipe 50, that is, no fluid exists in the first cavity 10. In the cooling condition of the heat pump unit 2, the first liquid inlet pipe 40 is turned on, so that the fluid flowing through the second heat exchanger 702 can flow into the hollow cavity. The second liquid inlet pipe 50 is turned on or off according to the fluid pressure of the first liquid inlet pipe 40 to control the amount of fluid flowing from the second heat exchanger 702 into the first cavity 10, so as to control the moving position of the buoyancy lifting structure 30.

[0076] Alternatively, as Figure 1 and Figure 2 As shown, the second end of the second liquid inlet pipe 50 is connected to the first liquid inlet pipe 40. In this way, only the second end of the first liquid inlet pipe 40 needs to be connected to the second heat exchanger 702 to achieve communication between the second heat exchanger 702 and the first cavity 10 and the hollow cavity.

[0077] Alternatively, as Figure 1 and Figure 2 As shown, the heat pump unit further includes a first refrigerant pipe 80 and a second refrigerant pipe 90. The first refrigerant pipe 80 is in communication with the first heat exchanger 701. The second refrigerant pipe 90 is in communication with the second heat exchanger 702. Both the first refrigerant pipe 80 and the second refrigerant pipe 90 extend into the second cavity 20, and the first refrigerant pipe 80 extends longer than the second refrigerant pipe 90.

[0078] In this disclosed embodiment, since the amount of refrigerant injected into the same heat pump unit 2 is constant, the amount of refrigerant participating in the circulation during heating operation will be less than the amount of refrigerant participating in the circulation during cooling operation. Therefore, the length of the first refrigerant tube 80 extending into the second cavity 20 is greater than the length of the second refrigerant tube 90 extending into the second cavity 20. In this way, in the heating condition, the first refrigerant tube 80 serves as the liquid inlet tube and the second refrigerant tube 90 serves as the liquid outlet tube, so that the liquid outlet volume is less than the liquid inlet volume, thereby allowing the excess refrigerant in the heat pump unit 2 to be stored in the liquid reservoir 1; in the cooling condition, the second refrigerant tube 90 serves as the liquid inlet tube and the first refrigerant tube 80 serves as the liquid storage tube, so that the amount of refrigerant participating in the circulation is large, and the refrigerant stored in the liquid reservoir 1 will also participate in the refrigeration cycle.

[0079] Alternatively, as Figure 2As shown, the heat pump unit 2 further includes a compressor 703 and a four-way valve 704. The compressor 703 is connected to the first heat exchanger 701 and the second heat exchanger 702 through the four-way valve 704, so that the heat pump unit 2 can switch the fluid flow direction in the cooling mode and the heating mode.

[0080] Alternatively, as Figure 2 As shown, the heat pump unit 2 further includes a first throttling device 100 and a second throttling device 110. The first end of the first throttling device 100 is in communication with the second refrigerant pipe 90, and the second end is in communication with the second heat exchanger 702. The first end of the second throttling device 110 is in communication with the first liquid inlet pipe 40 and the second liquid inlet pipe 50, respectively, and the second end is in communication with the second heat exchanger 702. In this way, in the heating mode, the compressor 703 compresses the refrigerant and discharges high-temperature and high-pressure gas, which is condensed into medium-temperature and high-pressure refrigerant through the first heat exchanger 701. The medium-temperature and high-pressure refrigerant flows out through the liquid accumulator 1 and is throttled by the first throttling device 100 to flow out low-temperature and low-pressure refrigerant. The low-temperature and low-pressure refrigerant flows through the second heat exchanger 702 and returns to the compressor 703. In the cooling mode, the compressor 703 compresses the refrigerant and discharges high-temperature and high-pressure gas, which is condensed into medium-temperature and high-pressure refrigerant through the second heat exchanger 702. Part of the medium-temperature and high-pressure refrigerant is throttled by the first throttling device 100 to flow out low-temperature and low-pressure refrigerant and flow into the second cavity 20, and part of it is throttled by the second throttling device 110 to flow out low-temperature and low-pressure refrigerant. Part of the low-temperature and low-pressure refrigerant flows into the hollow cavity of the buoyancy lifting structure 30, and part of the low-temperature and low-pressure refrigerant flows into the interior of the first cavity 10 as needed. Therefore, by providing the first throttling device 100 and the second throttling device 110, the medium-temperature and high-pressure refrigerant is throttled to a low-temperature and low-pressure refrigerant, thereby realizing the refrigerant circulation of the heat pump unit 2. In addition, the first throttling device 100 and the second throttling device 110 are provided simultaneously to prevent all the refrigerant flowing out of the second heat exchanger 702 from flowing into the unthrottled flow path.

[0081] For example, the second throttling device 110 may be a throttling capillary tube.

[0082] Alternatively, as Figure 2 As shown, the heat pump unit 2 further includes a solenoid valve 120 and / or a flow valve 130. The solenoid valve 120 is disposed on the pipeline between the first cavity and the second heat exchanger to control the flow of the second liquid inlet pipe 50. The flow valve 130 is disposed on the pipeline between the hollow cavity and the second heat exchanger to control the amount of fluid flowing into the buoyant lifting structure 30.

[0083] Specifically, if Figure 2 As shown, the solenoid valve 120 is disposed on the second liquid inlet pipe 50 , and / or the flow valve 130 is disposed on the first liquid inlet pipe 40 .

[0084] In this disclosed embodiment, the solenoid valve 120 opens or closes the second liquid inlet pipe 50, thereby controlling the amount of fluid in the first chamber 10 and, in turn, the height of the buoyant lifting structure 30. This allows precise control of the amount of refrigerant flowing from the cavity of the buoyant lifting structure 30 into the second chamber 20. The flow valve 130 is provided to adjust the amount of fluid flowing from the first liquid inlet pipe 40 into the cavity of the buoyant lifting structure 30.

[0085] Alternatively, as Figure 2 As shown, the heat pump unit 2 further includes a pressure sensor 140 , which is disposed on the first liquid inlet pipe 40 and is used to detect the fluid pressure in the first liquid inlet pipe 40 .

[0086] Optionally, the portion of the first liquid inlet pipe 40 in the first cavity 10 is a soft pipe, the length of which is greater than or equal to the height of the first cavity, and can extend along with the movement of the buoyancy lifting structure 30 .

[0087] For example, Figure 1 As shown, the distance between the lowest one-way flow-guiding hole 60 among the multiple one-way flow-guiding holes 60 and the bottom wall of the first cavity 10 is greater than the distance between the liquid outlet and the bottom wall of the first cavity 10 when the buoyancy lifting structure 30 is in the initial state. The initial state of the buoyancy lifting structure 30 means that the buoyancy lifting structure 30 is at the bottom of the first cavity 10.

[0088] Alternatively, as Figure 2 As shown, the heat pump unit 2 also includes a piston device 150. The piston device 150 is connected to the portion of the liquid inlet pipe between the control valve 120 and the first cavity 10 in the second liquid inlet pipe 50. The piston device 150 includes an upper cavity 1501, a lower cavity 1502, and a piston located between the upper and lower cavities, wherein the area size of the upper cavity 1501 and the lower cavity 1502 is adjusted by the up and down movement of the piston. The upper cavity 1501 is used to store fluid, and the lower cavity 1502 is provided with an air hole for injecting or discharging gas to make the piston move up and down, so that the fluid in the upper cavity 1501 flows into the first cavity 10 or the fluid in the first cavity 10 flows into the upper cavity 1501.

[0089] It should be noted that initially, the lower chamber 1502 is filled with gas, causing the piston to be located at the uppermost end of the piston assembly 150. When the first chamber 10 is initially filled with fluid, the control valve 120 is closed, and the gas in the lower chamber 1502 is expelled to push the piston downward, thereby drawing the fluid from the first chamber 10 into the upper chamber 1501, thereby partially or completely expelling the fluid from the first chamber 10. Alternatively, if fluid is required to flow into the first chamber 10, and if fluid is stored in the upper chamber 1501, gas is injected into the lower chamber 1502 to control the upward movement of the piston, allowing the fluid in the upper chamber 1501 to flow into the first chamber 10. At this point, the control valve 120 can be either open or closed.

[0090] Exemplarily, when the fluid in the upper cavity 1501 flows into the first cavity 10 , the control valve 120 is closed.

[0091] Alternatively, as Figure 2 As shown, the heat pump unit 2 further includes a valve body 160 , which is disposed between the piston device 150 and the second liquid inlet pipe 90 . The valve body 160 is opened or closed to open or close the pipeline between the piston device 150 and the first cavity 10 .

[0092] Specifically, when heat pump unit 2 is in heating mode, compressor 703 compresses the refrigerant, discharging high-temperature, high-pressure gas. This high-temperature, high-pressure gas condenses into medium-temperature, high-pressure refrigerant through first heat exchanger 701. This medium-temperature, high-pressure refrigerant enters second chamber 20 through first refrigerant pipe 80. At this time, no refrigerant flows in or out of first chamber 10. Refrigerant participating in the heating cycle flows out of second refrigerant pipe 90, passes through first throttling device 100, and flows out as low-temperature, low-pressure refrigerant. It then evaporates into low-temperature, low-pressure gas through second heat exchanger 702 and flows back into compressor 703, continuing the heating cycle. Refrigerant not participating in the heating cycle is stored in liquid reservoir 1. In heating mode, liquid reservoir 1 only has a liquid storage function.

[0093] Specifically, when the heat pump unit 2 is in cooling mode, the compressor 703 compresses the refrigerant and discharges high-temperature, high-pressure gas. This high-temperature, high-pressure gas is condensed into medium-temperature, high-pressure refrigerant through the second heat exchanger 702. A portion of this medium-temperature, high-pressure refrigerant passes through the first throttling device 100, flowing out as low-temperature, low-pressure refrigerant, and then enters the second chamber 20 through the second refrigerant pipe 90. Another portion is throttled by the second throttling device 110 and then split into two paths. One path flows into the first chamber 10 of the liquid reservoir 1 as needed through the second liquid inlet pipe 50, and the other path flows into the hollow cavity of the buoyancy lifting structure 30 through the first liquid inlet pipe 40. At the same time, when the first chamber 10 is filled with fluid, the amount of fluid in the first chamber 10 is adjusted by the valve body 160 and the piston device 150.

[0094] Optionally, the heat pump unit further includes an electronic control device, which includes a processor for obtaining the fluid pressure at a preset position and controlling the opening and closing state of the switch structure, thereby realizing various functions of the heat pump unit.

[0095] Combine Figure 1 and 2 The heat pump unit shown in the embodiment of the present disclosure provides a method for controlling the heat pump unit, and the execution subject of the method can be a processor, such as Figure 3 As shown, the method includes:

[0096] S301: When the heat pump unit is in cooling operation, the processor obtains the fluid pressure at a preset position.

[0097] The preset position is between the hollow cavity and the second heat exchanger. For example, the preset position is on the first liquid inlet pipe.

[0098] S302: The processor controls the on / off state of the switch structure according to the fluid pressure to control the amount of fluid flowing from the hollow cavity to the second cavity.

[0099] The open and close state includes an open state or a closed state.

[0100] In the disclosed embodiment, during the cooling operation of the heat pump unit, the fluid flows through the second heat exchanger, the liquid reservoir and the first heat exchanger in sequence. Since the second heat exchanger is respectively connected to the second cavity and the hollow cavity, part of the fluid flowing through the second heat exchanger flows into the hollow cavity of the buoyancy lifting structure, and part flows into the second cavity. Since the hollow cavity and the second cavity are controlled by a switch structure, the passage between the hollow cavity and the second cavity is connected, or the passage between the hollow cavity and the second cavity is cut off. In this way, by detecting the fluid pressure at a preset position, that is, the fluid pressure before entering the liquid reservoir, and controlling the opening and closing state of the switch structure according to the fluid pressure, the fluid amount of the heat pump unit can be self-regulated, thereby adjusting the amount of fluid in the liquid reservoir that participates in the fluid circulation of the heat pump unit, improving the control accuracy of the fluid circulation amount in the refrigeration condition, and thus improving the overall operating efficiency and stability of the heat pump unit.

[0101] Optionally, the processor controlling the on / off state of the switch structure based on the fluid pressure includes: when the fluid pressure is less than a preset pressure, the processor controlling the switch structure to an open state to allow the fluid in the hollow cavity to flow unidirectionally into the second cavity. And / or, when the fluid pressure is greater than a preset pressure, the processor controlling the switch structure to a closed state to prevent the fluid in the hollow cavity from flowing into the second cavity. And / or, when the fluid pressure is equal to the preset pressure, the processor obtaining the current on / off state of the switch structure and controlling the switch structure to maintain the current on / off state.

[0102] In the disclosed embodiment, when the fluid pressure is less than the preset pressure, indicating that the refrigerant participating in the circulation in the heat pump unit is insufficient, the control switch structure is in the open state, so that the refrigerant in the hollow cavity flows into the second cavity and is then discharged by the second cavity, so as to replenish the refrigerant participating in the refrigeration operation in time. When the fluid pressure is greater than the preset pressure, indicating that the refrigerant participating in the circulation in the heat pump unit is sufficient, that is, the refrigerant in the second cavity is sufficient to meet the operating requirements, the control switch structure is in the closed state. When the fluid pressure is equal to the preset pressure, indicating that the current amount of refrigerant can meet the refrigeration requirements of the heat pump unit, the operation continues according to the current open and closed state of the switch structure. In this way, effective monitoring and precise control of the fluid pressure of the heat pump unit are achieved, and the stability of the operation of the heat pump unit is further improved.

[0103] Optionally, the processor determines the preset pressure in the following manner: the processor obtains an operating frequency of a compressor of the heat pump unit, obtains a liquid pipe temperature of the first heat exchanger, and determines the preset pressure based on the operating frequency of the compressor and the liquid pipe temperature of the first heat exchanger.

[0104] In this disclosed embodiment, the compressor operating frequency and the liquid pipe temperature of the first heat exchanger can accurately reflect the actual operating conditions of the heat pump unit. Based on these actual operating conditions, the preset pressure can be accurately determined. This helps to precisely control the amount of refrigerant involved in the cycle and maintain the stability of the heat pump unit's operation.

[0105] Optionally, the processor determining the preset pressure based on the compressor operating frequency and the liquid pipe temperature of the first heat exchanger includes: the processor determining the refrigerant saturation temperature based on the compressor operating frequency and the liquid pipe temperature of the first heat exchanger. The processor determines the preset pressure corresponding to the refrigerant saturation temperature based on a preset first correspondence. In this way, the refrigerant saturation temperature can be accurately determined based on the compressor operating frequency and the liquid pipe temperature of the first heat exchanger, thereby accurately determining the preset pressure.

[0106] Optionally, the processor determining the refrigerant saturation temperature based on the compressor operating frequency and the liquid pipe temperature of the first heat exchanger includes: the processor calculating Ps_t = Thi - F / D to obtain the refrigerant saturation temperature, where Ps_t is the refrigerant saturation temperature, Thi is the liquid pipe temperature of the first heat exchanger, F is the compressor operating frequency, and D is the first coefficient.

[0107] For example, the first coefficient can be pre-set according to actual system characteristics and working requirements. For example, the value interval of the first coefficient is [7, 8]. Specifically, the first coefficient can be set to 7.2, 7.4 or 7.6.

[0108] Optionally, the processor determines the preset pressure in the following manner: the processor obtains a liquid pipe temperature of the first heat exchanger, determines a refrigerant saturation temperature based on the liquid pipe temperature of the first heat exchanger, and determines a preset pressure corresponding to the refrigerant saturation temperature based on a preset first correspondence.

[0109] Optionally, the processor determining the refrigerant saturation temperature according to the liquid pipe temperature of the first heat exchanger includes: the processor calculating Ps_t=Thi-A to obtain the refrigerant saturation temperature. In this way, the refrigerant saturation temperature can be accurately determined.

[0110] Wherein, A is a second coefficient. Exemplarily, the second coefficient can be pre-set based on actual system characteristics and operating requirements. Exemplarily, the second coefficient is determined as follows: obtaining a compressor operating frequency. Determining the second coefficient based on the compressor operating frequency includes, for example, determining the second coefficient corresponding to the compressor operating frequency based on a preset third correspondence.

[0111] Specifically, Table 1 shows an optional third corresponding relationship between the compressor operating frequency and the second coefficient.

[0112] Table 1

[0113] A Compressor operating frequency (Hz) [2.76，7.112) [20，54) [7.112，7.688) [54，58.5) [7.688，9.326) [58.5，71.3) [9.326，9.569) [71.3，73.2)

[0114] For example, Table 2 shows a first correspondence between an optional refrigerant saturation temperature and a preset pressure.

[0115] Table 2

[0116] Preset pressure (MPa) Ps_t(℃) [0.8131，0.86647) [0，2) [0.86647，0.92245) [2，4) [0.92245，0.98113) [4，6) [0.98113，1.0426) [6，8) [1.0426，1.1069) [8，10)

[0117] In this disclosed embodiment, the algorithm utilizes two real-time changing parameters, the compressor operating frequency and the liquid pipe temperature of the first heat exchanger, to determine the preset pressure, so that the preset pressure can be automatically adjusted as the system operating status changes, thereby achieving dynamic optimization of system performance.

[0118] Optionally, the processor determines the preset pressure in the following manner: the processor obtains an ambient temperature on the air side of the heat pump unit. The processor obtains a water outlet temperature on the user side of the heat pump unit. The processor determines the preset pressure based on the ambient temperature on the air side and the water outlet temperature on the user side.

[0119] In this disclosed embodiment, the ambient air temperature directly affects the heat pump unit's ability to absorb or release heat from the environment, while the user-side water outlet temperature reflects the heat pump unit's actual heating or cooling performance. Therefore, determining the preset pressure based on both the ambient air temperature and the user-side water outlet temperature makes the determined preset pressure more reasonable. By using this preset pressure to determine the fluid pressure and control the refrigerant amount involved in the refrigeration cycle, the heat pump unit's energy efficiency can be improved, reducing energy waste.

[0120] Optionally, the processor determines the preset pressure according to the ambient temperature on the air side and the outlet water temperature on the user side, including: the processor determines the preset pressure corresponding to the ambient temperature on the air side and the outlet water temperature on the user side according to a preset second corresponding relationship.

[0121] For example, Table 3 shows an optional second correspondence between the ambient temperature on the air side, the outlet water temperature on the user side, and the preset pressure.

[0122] Table 3

[0123] Preset pressure (MPa) Ambient temperature on the air side (°C) User side water outlet temperature (℃) [3，6) [8，20) [5，7) [6，10) [20，24.5) [7，15) [10，14) [24.5，31.5) [15，20) [14，18) [31.5，38) [20，25)

[0124] In the disclosed embodiment, the preset pressure is determined through the second corresponding relationship, which makes the process more convenient and improves comparison efficiency.

[0125] Optionally, the processor controls the on / off state of the switch structure as follows: the processor controls the liquid outlet of the buoyancy lifting structure to correspond with the one-way guide hole, thereby placing the switch structure in an open state. And / or the processor controls the liquid outlet of the buoyancy lifting structure to not correspond with the one-way guide hole, thereby placing the switch structure in a closed state.

[0126] In the disclosed embodiment, the opening and closing state of the switch structure is controlled by controlling whether the liquid outlet of the buoyancy lifting structure corresponds to the one-way guide hole. This control method is more accurate and reasonable.

[0127] Optionally, the processor controls the solenoid valve to be in an open state so that the liquid outlet of the buoyancy lifting structure is sequentially aligned with the plurality of one-way guide holes. And / or, the processor controls the solenoid valve to be in a closed state so as to prevent the fluid flowing through the second heat exchanger from flowing into the first cavity, so that the liquid outlet of the buoyancy lifting structure is not aligned with the one-way guide holes.

[0128] In this disclosed embodiment, the solenoid valve is controlled to be in an open state to allow fluid flowing through the second heat exchanger to flow into the first cavity, thereby adjusting the movement position of the buoyancy lifting structure so that the liquid outlet of the buoyancy lifting structure is sequentially aligned with the plurality of one-way flow guide holes. The solenoid valve is controlled to be in a closed state to prevent fluid flowing through the second heat exchanger from flowing into the first cavity, so that the buoyancy lifting structure is at the bottom of the first cavity, thereby causing the liquid outlet of the buoyancy lifting structure to be in a non-aligned state with the one-way flow guide holes. Among them, it can be understood that the control solenoid valve is in a closed state. Since the distance between the lowest one-way guide hole and the bottom wall of the first cavity is greater than the distance between the liquid outlet and the bottom wall of the first cavity 10 when the buoyancy lifting structure 30 is in the initial state, when the buoyancy lifting structure 30 is at the bottom of the first cavity 10, it does not correspond to all the one-way guide holes 60. In this way, the refrigerant in the hollow cavity will not flow to the second cavity 20. Only the refrigerant in the second cavity 20 of the liquid storage tank 1 flows out through the first refrigerant pipe 80 and enters the first heat exchanger 701 to participate in the refrigerant circulation of the heat pump unit 2.

[0129] Optionally, the method also includes: when the liquid outlet of the buoyancy lifting structure is in a corresponding state with the uppermost one-way guide hole among the multiple one-way guide holes and the fluid pressure is less than a preset pressure, increasing the opening of the flow valve to increase the amount of fluid flowing into the hollow cavity.

[0130] like Figure 4 As shown, the embodiment of the present disclosure provides another method for controlling a heat pump unit.

[0131] The method includes:

[0132] S401: When the heat pump unit is in cooling operation, the processor obtains the fluid pressure at a preset position.

[0133] S402: When the fluid pressure is less than a preset pressure, the processor controls the solenoid valve to be in an open state, so that the liquid outlet of the buoyancy lifting structure is in a corresponding state with the multiple one-way guide holes in sequence.

[0134] S403, when the fluid pressure is less than the preset pressure and the liquid outlet of the buoyancy lifting structure is in a corresponding state with the uppermost one-way guide hole among the multiple one-way guide holes, the processor increases the opening of the flow valve to increase the amount of fluid flowing into the hollow cavity.

[0135] The opening of the flow valve is increased to increase the amount of fluid flowing into the hollow cavity until the fluid pressure is equal to the preset pressure.

[0136] S404: When the fluid pressure is greater than a preset pressure, the processor controls the solenoid valve to be in a closed state, so that the liquid outlet of the buoyancy lifting structure and the one-way guide hole are in a non-corresponding state.

[0137] S405 , when the fluid pressure is equal to the preset pressure, the processor obtains the current open / closed state of the solenoid valve and controls the solenoid valve to be in the current open / closed state.

[0138] In this disclosed embodiment, when the liquid outlet of the buoyancy lifting structure is already in a corresponding state with the uppermost one-way guide hole among the multiple one-way guide holes, if the fluid pressure is still less than the preset pressure, the opening of the flow valve is increased to increase the amount of fluid flowing into the hollow cavity to supplement the amount of refrigerant in the second cavity, thereby further improving the stability of the operation of the heat pump unit.

[0139] Optionally, after the liquid outlet of the buoyancy lifting structure is in a corresponding state with the topmost one-way guide hole among the multiple one-way guide holes, it also includes: when the fluid pressure is greater than the preset pressure, opening the valve body and sucking all the fluid in the first cavity into the upper cavity.

[0140] Specifically, when the valve body is opened, the gas in the lower chamber of the piston device is exhausted to move the piston downward, so that all the fluid in the first chamber is sucked into the upper chamber, so that the upper chamber of the piston device is filled with fluid.

[0141] It is understood that when the fluid in the first cavity flows into the upper cavity, the buoyancy lifting structure descends. When all the fluid in the first cavity is sucked into the upper cavity, the buoyancy lifting structure descends to the bottom of the first cavity.

[0142] In this disclosed embodiment, when the liquid outlet of the buoyancy lifting structure is already in a corresponding state with the topmost unidirectional guide hole among the multiple unidirectional guide holes, if the fluid pressure is greater than the preset pressure, the fluid in the first cavity is introduced into the piston device for storage, thereby further improving the stability of the operation of the heat pump unit.

[0143] Optionally, after the upper chamber of the piston device stores the fluid, it also includes: opening or closing the valve body according to the fluid pressure, and allowing the fluid in the upper chamber to flow into the first chamber, or allowing the fluid in the first chamber to flow into the upper chamber, thereby controlling the corresponding state of the liquid outlet of the buoyancy lifting structure and the one-way guide hole.

[0144] Specifically, when the fluid pressure is less than a preset pressure, the solenoid valve is controlled to be closed, and the valve body is opened, directing the fluid in the upper chamber into the first chamber. In this way, the amount of fluid in the first chamber can be adjusted solely by the fluid stored in the piston device, thereby enabling the buoyancy lifting structure to move up and down within the first chamber, thereby controlling whether the buoyancy lifting structure's liquid outlet and the one-way guide hole are aligned or not aligned. The piston device allows fluid to flow in or out of the first chamber, fully utilizing the fluid and avoiding fluid waste.

[0145] Combine Figure 5 As shown, an embodiment of the present disclosure provides an apparatus 200 for controlling a heat pump unit, comprising an acquisition module 21 and a control module 22. The acquisition module 21 is configured to obtain the fluid pressure at a preset position when the heat pump unit is in cooling operation; the preset position is between the hollow cavity and the second heat exchanger; the control module 22 is configured to control the on / off state of the switch structure based on the fluid pressure, thereby controlling the amount of fluid flowing from the hollow cavity to the second cavity, and thereby controlling the amount of fluid in the liquid reservoir participating in the fluid circulation of the heat pump unit.

[0146] The device 200 for controlling a heat pump unit, provided in an embodiment of the present disclosure, detects fluid pressure at a preset location—that is, the fluid pressure before entering the liquid reservoir—and controls the on / off state of a switch structure based on this fluid pressure. This enables the heat pump unit to self-regulate the fluid volume, thereby adjusting the amount of fluid in the liquid reservoir that participates in the heat pump unit's fluid circulation. This improves the control accuracy of the fluid circulation volume during cooling operation, thereby enhancing the overall operating efficiency and stability of the heat pump unit.

[0147] Combine Figure 6 As shown, an embodiment of the present disclosure provides a device 300 for controlling a heat pump unit, comprising a processor 600 and a memory 601. Optionally, the device 300 may further comprise a communication interface 602 and a bus 603. The processor 600, the communication interface 602, and the memory 601 may communicate with each other via the bus 603. The communication interface 602 may be used for information transmission. The processor 600 may call the logic instructions in the memory 601 to execute the method for controlling a heat pump unit of the above embodiment.

[0148] In addition, the logic instructions in the memory 601 can be implemented in the form of software functional units and can be stored in a computer-readable storage medium when sold or used as an independent product.

[0149] Memory 601, as a computer-readable storage medium, can be used to store software programs and computer-executable programs, such as program instructions / modules corresponding to the methods in the embodiments of the present disclosure. Processor 600 executes the program instructions / modules stored in memory 601 to perform functional applications and data processing, thereby implementing the method for controlling a heat pump unit in the above-described embodiments.

[0150] The memory 601 may include a program storage area and a data storage area. The program storage area may store an operating system and at least one application required for a function; the data storage area may store data generated based on the use of the terminal device. Furthermore, the memory 601 may include a high-speed random access memory and a non-volatile memory.

[0151] The embodiment of the present disclosure provides a heat pump unit, comprising: a heat pump unit body, a first heat exchanger, a second heat exchanger, a liquid reservoir, and the above-mentioned device 200 (300) for controlling the heat pump unit. The device 200 (300) for controlling the heat pump unit is installed on the heat pump unit body. The installation relationship described here is not limited to placement inside the heat pump unit body, but also includes installation connections with other components of the heat pump unit, including but not limited to physical connections, electrical connections, or signal transmission connections. It can be understood by those skilled in the art that the device 200 (300) for controlling the heat pump unit can be adapted to a feasible heat pump unit body, thereby realizing other feasible embodiments. Among them, the first heat exchanger is arranged in the heat pump unit body and is located on the user side; the second heat exchanger is arranged in the heat pump unit body and is located on the air side; the liquid reservoir is arranged in the heat pump unit body, including a first cavity, a second cavity having a common first cavity wall with the first cavity, a buoyancy lifting structure and a switch structure; the second cavity is connected to the second heat exchanger and the first heat exchanger respectively; the buoyancy lifting structure is arranged in the first cavity, and has a hollow cavity in its interior that is connected to the second heat exchanger, so that the fluid flowing through the second heat exchanger can flow into the hollow cavity; the switch structure is arranged between the hollow cavity and the second cavity, and by controlling the switch structure to be in an open state or a closed state, the fluid in the hollow cavity can flow into the second cavity in a unidirectional manner or the fluid in the hollow cavity can be prohibited from flowing into the second cavity. The embodiment of the present disclosure provides a computer-readable storage medium storing computer-executable instructions, and the computer-executable instructions are configured to execute the above-mentioned method for controlling a heat pump unit.

[0152] The technical solutions of the embodiments of the present disclosure may be embodied in the form of a software product, which is stored in a storage medium and includes one or more instructions for causing a computer device (which may be a personal computer, a server, or a network device, etc.) to execute all or part of the steps of the method described in the embodiments of the present disclosure. The aforementioned storage medium may be a non-transitory storage medium, such as a USB flash drive, a mobile hard disk, a read-only memory (ROM), a random access memory (RAM), a magnetic disk, or an optical disk, among other media capable of storing program code.

[0153] The above description and the accompanying drawings fully illustrate the embodiments of the present disclosure so that those skilled in the art can practice them. Other embodiments may include structural, logical, electrical, process and other changes. The embodiments represent only possible variations. Unless explicitly required, individual components and functions are optional, and the order of operations may vary. Parts and features of some embodiments may be included in or replace parts and features of other embodiments. Moreover, the words used in this application are only used to describe the embodiments and are not used to limit the claims. As used in the description of the embodiments and claims, unless the context clearly indicates otherwise, the singular forms "a", "an" and "the" are intended to also include plural forms. Similarly, the term "and / or" as used in this application refers to any and all possible combinations of one or more associated listings. In addition, when used in this application, the term "comprise" and its variations "comprises" and / or comprising refer to the presence of stated features, wholes, steps, operations, elements, and / or components, but do not exclude the presence or addition of one or more other features, wholes, steps, operations, elements, components and / or groups of these. In the absence of further restrictions, an element defined by the sentence "comprising a..." does not exclude the presence of other identical elements in the process, method or device that includes the element. In this article, each embodiment may focus on the differences from other embodiments, and the same and similar parts between the various embodiments can be referenced to each other. For the methods, products, etc. disclosed in the embodiments, if they correspond to the method part disclosed in the embodiments, then the relevant parts can be found in the description of the method part.

[0154] Those skilled in the art will appreciate that the units and algorithm steps of each example described in conjunction with the embodiments disclosed herein can be implemented in electronic hardware, or a combination of computer software and electronic hardware. Whether these functions are performed in hardware or software may depend on the specific application and design constraints of the technical solution. The technicians may use different methods to implement the described functions for each specific application, but such implementation should not be considered to be beyond the scope of the embodiments of the present disclosure. The technicians will clearly understand that, for the convenience and brevity of description, the specific working processes of the systems, devices and units described above can refer to the corresponding processes in the aforementioned method embodiments and will not be repeated here.

[0155] In the embodiments disclosed herein, the disclosed methods and products (including but not limited to devices, equipment, etc.) can be implemented in other ways. For example, the device embodiments described above are merely illustrative. For example, the division of the units can be merely a logical functional division. In actual implementation, there may be other division methods, such as multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed. In addition, the coupling or direct coupling or communication connection between each other shown or discussed can be through some interfaces, indirect coupling or communication connection of devices or units, and can be electrical, mechanical or other forms. The units described as separate components may or may not be physically separated, and the components shown as units may or may not be physical units, that is, they may be located in one place, or they may be distributed on multiple network units. Some or all of the units may be selected to implement this embodiment according to actual needs. In addition, the functional units in the embodiments of the present disclosure may be integrated into a processing unit, or each unit may exist physically separately, or two or more units may be integrated into one unit.

[0156] The flowcharts and block diagrams in the accompanying drawings show the possible implementation architectures, functions and operations of the systems, methods and computer program products according to the embodiments of the present disclosure. In this regard, each box in the flowchart or block diagram can represent a module, program segment or part of the code, and the module, program segment or part of the code contains one or more executable instructions for implementing the specified logical functions. In some alternative implementations, the functions marked in the box can also occur in an order different from that marked in the accompanying drawings. For example, two consecutive boxes can actually be executed substantially in parallel, or they can sometimes be executed in the opposite order, which can depend on the functions involved. In the descriptions corresponding to the flowcharts and block diagrams in the accompanying drawings, the operations or steps corresponding to different boxes can also occur in an order different from that disclosed in the description, and sometimes there is no specific order between different operations or steps. For example, two consecutive operations or steps can actually be executed substantially in parallel, or they can sometimes be executed in the opposite order, which can depend on the functions involved. Each block in the block diagrams and / or flowcharts, and combinations of blocks in the block diagrams and / or flowcharts, may be implemented by a dedicated hardware-based system that performs the specified function or action, or may be implemented by a combination of dedicated hardware and computer instructions.

Claims

1. A method for controlling a heat pump unit, characterized in that: The heat pump unit includes a liquid reservoir, a first heat exchanger located on the user side, and a second heat exchanger located on the air side. The liquid reservoir includes a first cavity, a second cavity having a common first cavity wall with the first cavity, a buoyancy lifting structure, and a switch structure. The second cavity is connected to the second heat exchanger and the first heat exchanger respectively. The buoyancy lifting structure is disposed in the first cavity and has a hollow cavity therein that is connected to the second heat exchanger, allowing fluid flowing through the second heat exchanger to flow into the hollow cavity. The switch structure is disposed between the hollow cavity and the second cavity, and the switch structure is controlled to be in an open state or a closed state so as to allow the fluid in the hollow cavity to flow into the second cavity in a unidirectional manner or to prohibit the fluid in the hollow cavity from flowing into the second cavity. The method includes: When the heat pump unit is in cooling operation, the fluid pressure at a preset position is obtained; wherein the preset position is between the hollow cavity and the second heat exchanger; The opening and closing states of the switch structure are controlled according to the fluid pressure to control the amount of fluid flowing from the hollow cavity to the second cavity.

2. The method according to claim 1, characterized in that Control the open and close state of the switch structure according to the fluid pressure, including: When the fluid pressure is less than the preset pressure, the switch structure is controlled to be in an open state, so that the fluid in the hollow cavity flows into the second cavity in a unidirectional manner; and / or, When the fluid pressure is greater than a preset pressure, the switch structure is controlled to be in a closed state to prevent the fluid in the hollow cavity from flowing into the second cavity; and / or, When the fluid pressure is equal to the preset pressure, the current open / closed state of the switch structure is obtained, and the switch structure is controlled to be in the current open / closed state.

3. The method according to claim 2, characterized in that The heat pump unit also includes a compressor; the preset pressure is determined as follows: Get the compressor operating frequency of the heat pump unit; Obtaining the liquid pipe temperature of the first heat exchanger; The preset pressure is determined according to the operating frequency of the compressor and the liquid pipe temperature of the first heat exchanger.

4. The method according to claim 3, characterized in that The preset pressure is determined according to the operating frequency of the compressor and the liquid pipe temperature of the first heat exchanger, including: determining the refrigerant saturation temperature according to the operating frequency of the compressor and the liquid pipe temperature of the first heat exchanger; According to the preset first corresponding relationship, a preset pressure corresponding to the refrigerant saturation temperature is determined.

5. The method according to claim 2, characterized in that Determine the preset pressure as follows: Get the ambient temperature of the air side of the heat pump unit; Obtain the outlet water temperature of the user side of the heat pump unit; The preset pressure is determined based on the ambient temperature on the air side and the outlet water temperature on the user side.

6. The method according to claim 5, characterized in that The preset pressure is determined based on the ambient temperature on the air side and the outlet water temperature on the user side, including: According to the preset second corresponding relationship, the preset pressure corresponding to the ambient temperature on the air side and the outlet water temperature on the user side is determined.

7. The method according to any one of claims 1 to 6, characterized in that The buoyancy lifting structure is provided with a liquid outlet connected to the hollow cavity; the switch structure includes a plurality of one-way flow guide holes arranged along the height direction of the first cavity wall. When the fluid flowing through the second heat exchanger flows into the hollow cavity of the buoyancy lifting structure, the buoyancy lifting structure can move up and down in the first cavity under the buoyancy provided by the fluid inside the first cavity, and when the liquid outlet of the buoyancy lifting structure corresponds to the one-way flow guide hole, they can be tangent to each other and make the one-way flow guide hole unidirectional so that the fluid in the hollow cavity flows to the second cavity; the opening and closing state of the switch structure is controlled in the following manner: Controlling the liquid outlet of the buoyancy lifting structure and the one-way guide hole to be in a corresponding state so that the switch structure is in an open state; and / or, The liquid outlet of the buoyancy lifting structure is controlled to be in a non-corresponding state with the one-way guide hole, so that the switch structure is in a closed state.

8. The method according to claim 7, characterized in that The first cavity is in communication with the second heat exchanger; the heat pump unit further comprises a solenoid valve disposed on the pipeline between the first cavity and the second heat exchanger; wherein: Controlling the solenoid valve to be in an open state so that the liquid outlet of the buoyancy lifting structure is in a corresponding state with the multiple one-way flow guide holes in sequence; and / or, The solenoid valve is controlled to be in a closed state to prohibit the fluid flowing through the second heat exchanger from flowing into the first cavity, so that the liquid outlet of the buoyancy lifting structure and the one-way guide hole are in a non-corresponding state.

9. A device for controlling a heat pump unit, comprising a processor and a memory storing program instructions, characterized in that: The processor is configured to execute the method for controlling a heat pump unit according to any one of claims 1 to 8 when running the program instructions.

10. A heat pump unit, characterized in that: include: Heat pump unit body; The first heat exchanger is provided on the heat pump unit body and is located on the user side; A second heat exchanger is provided on the heat pump unit body and is located on the air side; The liquid reservoir is disposed in the heat pump unit body and includes a first cavity, a second cavity having a common first cavity wall with the first cavity, a buoyancy lifting structure, and a switch structure; the second cavity is respectively connected to the second heat exchanger and the first heat exchanger; the buoyancy lifting structure is disposed in the first cavity and has a hollow cavity therein that is connected to the second heat exchanger, so that the fluid flowing through the second heat exchanger can flow into the hollow cavity; The switch structure is disposed between the hollow cavity and the second cavity, and by controlling the switch structure to be in an open state or a closed state, the fluid in the hollow cavity is allowed to flow into the second cavity in a unidirectional manner or the fluid in the hollow cavity is prohibited from flowing into the second cavity; The device for controlling a heat pump unit according to claim 9 is installed on the heat pump unit body.

Images