Heat pump system and control method for heat pump system

Abstract

The invention relates to the technical field of heat pump systems, and discloses a heat pump system, comprising: a main circulation loop comprising a loop formed by sequentially connecting a variable-capacity compressor, a condenser, a first throttle valve, a flash tank, a second throttle valve and an evaporator, the variable-capacity compressor comprising an upper cylinder and a lower cylinder, and being internally provided with a variable-capacity port and an air supply port; one end of the variable-capacity pipeline is communicated with the variable-capacity opening, the other end of the variable-capacity pipeline is divided into a first branch and a second branch, the first branch is communicated with the air suction pipeline, and the second branch is communicated with the exhaust pipeline; one end of the air supply pipeline is communicated with the air supply port, and the other end is communicated with the flash tank; and one end of the bypass pipeline is communicated with the pipeline between the condenser and the first throttle valve, and the other end of the bypass pipeline is communicated with the pipeline between the flash tank and the second throttle valve. The heat pump system can achieve efficient and energy-saving operation under various working conditions, and wide-range capacity change and full-working-condition efficient operation of the heat pump system can be met at the same time. The invention further discloses a control method for the heat pump system.

Description

Technical Field

[0001] The present application relates to the technical field of heat pump systems, for example, to a heat pump system and a control method for the heat pump system. Background Art

[0002] At present, with the improvement of people's quality of life, heat pump systems are no longer used only to achieve a single heating, hot water or drying function. The higher demand for heat pump systems is to achieve air conditioning and cooling while performing heat pump heating, and to meet the demand for hot water when necessary, so as to achieve the purpose of one machine for multiple uses. The corresponding heat pump dual-generation and tri-generation air conditioners are currently also widely used. However, in order to simultaneously meet the high-efficiency and energy-saving operation of heat pump heating and air conditioning and cooling under all working conditions, the requirements for the heat pump system itself are relatively strict. Related technologies In order to solve the problem of insufficient low-temperature heating capacity of heat pumps, the heat pump compressor adopts single-stage air replenishment and enthalpy increase technology to improve the compressor's low-temperature heating capacity output.

[0003] In the process of implementing the embodiments of the present disclosure, it is found that there are at least the following problems in the related art:

[0004] The operating range of heat pump dual-generation and tri-generation air-conditioning systems is relatively wide, including low-temperature heating, cooling, low load or high load and other operating conditions. When the heat pump system in the related technology starts to increase enthalpy and operates in low pressure difference and small pressure ratio heating or cooling conditions, the compressor's air supply medium pressure is relatively difficult to control. If the air supply medium pressure is controlled too high, it will cause the air supply to carry liquid. If the air supply medium pressure is controlled too low, no air can be replenished, and the air supply enthalpy increase will be worse. At this time, the air supply enthalpy increase system with two throttling is complex to control, and it is difficult to coordinate the control of the two electronic expansion valves, which is easy to cause the energy efficiency of the heat pump air conditioning system to deteriorate. When the heat pump system is operating in low-load heating or cooling conditions, in order to reduce the capacity of the system, the related technology needs to reduce the speed of the compressor. At this time, when the compressor runs at a low speed, its electrical efficiency and volumetric efficiency will be reduced, and the energy efficiency of the entire heat pump system will also decrease accordingly. Therefore, the heat pump system in the related art cannot take into account the high energy efficiency requirements of low-temperature heating, cooling and low-load operation, and it is difficult to simultaneously meet the capacity changes and high energy efficiency requirements of the heat pump system in a wide range of all operating conditions.

[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 the present application, and therefore may include information that does not constitute the prior art known to ordinary technicians in the 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 components 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 heat pump system and a control method for the heat pump system, which can enable the heat pump system to achieve efficient and energy-saving operation under various operating conditions, which is beneficial for simultaneously meeting the wide range of capacity changes of the heat pump system and efficient operation under all operating conditions.

[0008] In some embodiments, the heat pump system includes: a main circulation loop, including a variable capacity compressor, a condenser, a first throttle valve, a flash trigger, a second throttle valve and an evaporator connected in sequence through a refrigerant pipeline to form a loop, the variable capacity compressor including an upper cylinder and a lower cylinder, and the variable capacity compressor is provided with a variable capacity port and an air supply port; a variable capacity pipeline, one end of which is connected to the variable capacity port of the variable capacity compressor, and the other end is divided into a first branch and a second branch, the first branch is connected to the suction pipeline of the variable capacity compressor, a first control valve is provided on the first branch, the second branch is connected to the exhaust pipeline of the variable capacity compressor, and a second control valve is provided on the second branch; an air supply pipeline, one end of which is connected to the air supply port of the variable capacity compressor, and the other end is connected to the flash trigger, and a third control valve is provided on the air supply pipeline; a bypass pipeline, one end of which is connected to the pipeline between the condenser and the first throttle valve, and the other end is connected to the pipeline between the flash trigger and the second throttle valve, and a fourth control valve is provided on the bypass pipeline.

[0009] In some embodiments, the air supply port is arranged on the lower cylinder, and the variable capacity compressor further includes: a one-way valve assembly, which is arranged on the lower cylinder corresponding to the air supply port and is used to limit the one-way flow of refrigerant from the air supply pipeline to the lower cylinder.

[0010] In some embodiments, the one-way valve assembly includes a one-way valve disc and a one-way valve baffle. The one-way valve disc cover is arranged at the air supply port. The one-way valve baffle includes a connecting portion and a limiting portion. The connecting portion is arranged above the one-way valve disc and is fixedly connected to the one-way valve disc. The limiting portion is arranged above the one-way valve disc opposite to the air supply port, and the lower end surface of the limiting portion has a gap with the one-way valve disc for limiting the opening of the one-way valve disc.

[0011] In some embodiments, a one-way valve seat is provided on the lower cylinder, a partition is sandwiched between the upper cylinder and the lower cylinder, the one-way valve seat and the partition constitute an accommodating cavity, the one-way valve assembly is arranged in the accommodating cavity, and the distance between the upper end surface of the one-way valve baffle and the upper end surface of the lower cylinder is h, h≤0.1mm.

[0012] In some embodiments, when the one-way valve assembly is disposed in the accommodating chamber, the remaining volume in the accommodating chamber is V 0 , 0.02mL≤V 0 ≤1mL.

[0013] In some embodiments, a slide groove is provided on the side of the lower cylinder facing the variable capacity port, and the variable capacity compressor also includes: a variable capacity slide, which is provided in the slide groove, and a groove is provided on the variable capacity slide; a pin, which is movably provided below the variable capacity slide, and a protrusion is provided on one end of the pin facing the variable capacity slide, and the protrusion is adapted to the groove of the variable capacity slide; an elastic member, connected to the pin, so that the pin can move between a free position and a clamping position, wherein when the pin moves to the free position, the protrusion of the pin is engaged with the groove of the variable capacity slide to limit the displacement of the variable capacity slide.

[0014] In some embodiments, the displacement of the upper cylinder is V 1 , the displacement of the lower cylinder is V 2 , 0.5≤V 1 / V 2 ≤0.8.

[0015] In some embodiments, the heat pump system further includes: a third branch, one end of which is connected to the air supply pipeline and the other end of which is connected to the variable volume pipeline, and a fifth control valve is provided on the third branch.

[0016] In some embodiments, a variable capacity tank is provided on the variable capacity pipeline; and / or, an air supply tank is provided on the air supply pipeline; and / or, a liquid distributor is provided on the air intake pipeline.

[0017] In some embodiments, applied to the above-mentioned heat pump system, the method includes: obtaining the operating frequency, exhaust pressure and suction pressure of the variable capacity compressor; determining the working mode of the heat pump system according to the operating frequency, exhaust pressure and suction pressure of the variable capacity compressor; and configuring the opening and closing states of each control valve according to the working mode of the heat pump system.

[0018] The heat pump system and the control method for the heat pump system provided by the embodiments of the present disclosure can achieve the following technical effects:

[0019] In the embodiment of the present disclosure, a two-cylinder variable capacity compressor is used, which has both variable capacity function and air supply function. The heat pump system is provided with a variable capacity pipeline, which is divided into a first branch connected to the suction pipeline and a second branch connected to the exhaust pipeline. By controlling the first branch and the second branch to be turned on or off, the variable capacity can be adjusted to control the single-cylinder or double-cylinder operation of the variable capacity compressor. At the same time, by controlling the conduction or disconnection of the air supply pipeline of the heat pump system, the opening or closing of the air supply enthalpy increase function of the variable capacity compressor can be controlled. The heat pump system is also provided with a bypass pipeline, which is arranged in parallel with the first throttle valve and the flasher. By controlling the conduction or disconnection of the bypass pipeline, the control of the number of throttling times can be further realized. Therefore, the embodiment of the present disclosure can construct a variety of working modes to adapt to the capacity requirements of the heat pump system under different working conditions, so that the heat pump system can achieve efficient and energy-saving operation under various working conditions, which is conducive to simultaneously meeting the wide range of capacity changes and efficient operation of the heat pump system under all working conditions.

[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, which do not limit the embodiments. Elements with the same reference numerals in the drawings are shown as similar elements, and the drawings do not constitute a scale limitation, and wherein:

[0022] Figure 1 is a structural schematic diagram of a heat pump system provided by an embodiment of the present disclosure;

[0023] Figure 2 is a schematic structural diagram of a variable capacity compressor provided by an embodiment of the present disclosure;

[0024] Figure 3 is a structural schematic diagram of a lower cylinder provided in an embodiment of the present disclosure;

[0025] Figure 4 The embodiment of the present disclosure provides Figure 3 Schematic diagram of the explosion of the lower cylinder;

[0026] Figure 5 is a structural schematic diagram of a one-way valve baffle provided in an embodiment of the present disclosure;

[0027] Figure 6 The embodiment of the present disclosure provides Figure 2 An enlarged schematic diagram of part A;

[0028] Figure 7 is a structural schematic diagram of another heat pump system provided by an embodiment of the present disclosure;

[0029] Figure 8 is a schematic diagram of a control method for a heat pump system provided by an embodiment of the present disclosure;

[0030] Fig. 9 is a schematic diagram of another control method for a heat pump system provided by an embodiment of the present disclosure;

[0031] Fig.10 is a schematic diagram of another control method for a heat pump system provided by an embodiment of the present disclosure;

[0032] Fig.11 is a schematic diagram of a control device for a heat pump system provided by an embodiment of the present disclosure;

[0033] Fig.12 It is a schematic diagram of an air conditioner provided in an embodiment of the present disclosure.

[0034] Reference numerals:

[0035] 10: main circulation loop; 11: variable capacity compressor; 111: upper cylinder; 112: lower cylinder; 113: variable capacity port; 114: air supply port; 115: one-way valve assembly; 1151: one-way valve disc; 1152: one-way valve baffle; 11521: connecting part; 11522: limiting part; 1153: one-way valve seat; 1154: one-way valve screw; 116: sliding plate groove; 117: variable capacity sliding plate; 1171: groove; 118: pin; 1181: bump; 119: elastic member; 1110: partition; 1111: lower bearing; 1112: lower cover plate; 1113: upper bearing; 1114: lower roller; 1115: crankshaft; 1116: motor rotor; 1117: motor stator; 111 8: exhaust port; 12: condenser; 13: first throttle valve; 14: flasher; 15: second throttle valve; 16: evaporator; 17: exhaust pipe; 18: intake pipe; 19: liquid distributor; 20: variable volume pipe; 21: first branch; 22: second branch; 23: variable volume tank; 30: air supply pipe; 31: air supply tank; 40: bypass pipe; 50: third branch; 61: first control valve; 62: second control valve; 63: third control valve; 64: fourth control valve; 65: fifth control valve; 71: first pressure sensor; 72: second pressure sensor; 80: control device for heat pump system; 81: processor; 82: memory; 83: communication interface; 84: bus; 90: air conditioner body. DETAILED DESCRIPTION

[0036] In order to be able to understand the features and technical contents 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 attached drawings are for reference only and are not used to limit the embodiments of the present disclosure. In the following technical description, for the 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.

[0037] The terms "first", "second", etc. in the specification and claims of the embodiments of the present disclosure and the above-mentioned drawings are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence. It should be understood that the terms used in this way can be interchanged where appropriate, so that the embodiments of the embodiments of the present disclosure described herein. In addition, the terms "including" and "having" and any variations thereof are intended to cover non-exclusive inclusions.

[0038] Unless otherwise stated, the term "plurality" means two or more.

[0039] 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 indicates: A or B.

[0040] The term "and / or" is a description of the association relationship between objects, indicating that three relationships can exist. For example, A and / or B means: A or B, or, A and B.

[0041] 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.

[0042] At present, with the improvement of people's quality of life, heat pump systems are no longer used only to achieve a single heating, hot water or drying function. The higher demand for heat pump systems is to achieve air conditioning and cooling while performing heat pump heating, and to meet the demand for hot water when necessary, so as to achieve the purpose of one machine for multiple uses. The corresponding heat pump dual-generation and tri-generation air conditioners are currently also widely used. However, in order to simultaneously meet the high-efficiency and energy-saving operation of heat pump heating and air conditioning and cooling under all working conditions, the requirements for the heat pump system itself are relatively strict. Related technologies In order to solve the problem of insufficient low-temperature heating capacity of heat pumps, the heat pump compressor adopts single-stage air replenishment and enthalpy increase technology to improve the compressor's low-temperature heating capacity output.

[0043] However, the operating range of heat pump dual-generation and tri-generation air-conditioning systems is relatively wide, including low-temperature heating, cooling, low load or high load and other operating conditions. When the heat pump system in the related technology starts to increase enthalpy and operates in low pressure difference and small pressure ratio heating or cooling conditions, the compressor's air supply medium pressure is relatively difficult to control. If the air supply medium pressure is controlled too high, it will cause the air supply to carry liquid. If the air supply medium pressure is controlled too low, no air can be replenished, and the air supply enthalpy increase will become worse. At this time, the air supply enthalpy increase system with two throttling is complex to control, and it is difficult to coordinate the control of the two electronic expansion valves, which is easy to cause the energy efficiency of the heat pump air conditioning system to deteriorate. When the heat pump system is operating in low-load heating or cooling conditions, in order to reduce the capacity of the system, the related technology needs to reduce the speed of the compressor. At this time, when the compressor runs at a low speed, its electrical efficiency and volumetric efficiency will be reduced, and the energy efficiency of the entire heat pump system will also decrease accordingly. Therefore, the heat pump system in the related art cannot take into account the high energy efficiency requirements of low-temperature heating, cooling and low-load operation, and it is difficult to simultaneously meet the capacity changes and high energy efficiency requirements of the heat pump system in a wide range of all operating conditions.

[0044] Combination Figure 1As shown, the embodiment of the present disclosure provides a heat pump system, including: a main circulation loop 10, a variable volume pipeline 20, an air supply pipeline 30 and a bypass pipeline 40. The main circulation loop 10 includes a variable volume compressor 11, a condenser 12, a first throttle valve 13, a flasher 14, a second throttle valve 15 and an evaporator 16 connected in sequence through a refrigerant pipeline to form a loop. The variable volume compressor 11 includes an upper cylinder 111 and a lower cylinder 112, and a variable volume port 113 and an air supply port 114 are provided in the variable volume compressor 11. The variable volume pipeline 20, one end of which is connected to the variable volume port 113 of the variable volume compressor 11, and the other end of which is divided into a first branch 21 and a second branch 22. The first branch 21 is connected to the suction pipeline 18 of the variable volume compressor 11, and a first control valve 61 is provided on the first branch 21. The second branch 22 is connected to the exhaust pipeline 17 of the variable volume compressor 11, and a second control valve 62 is provided on the second branch 22. The air supply pipeline 30 is connected to the air supply port 114 of the variable capacity compressor 11 at one end and to the flash igniter 14 at the other end. A third control valve 63 is provided on the air supply pipeline 30. The bypass pipeline 40 is connected to the pipeline between the condenser 12 and the first throttle valve 13 at one end and to the pipeline between the flash igniter 14 and the second throttle valve 15 at the other end. A fourth control valve 64 is provided on the bypass pipeline 40.

[0045] The heat pump system provided by the embodiment of the present disclosure adopts a two-cylinder variable capacity compressor 11, which has both variable capacity function and air supply function. The heat pump system is provided with a variable capacity pipeline 20, which is divided into a first branch 21 connected to the intake pipeline 18 and a second branch 22 connected to the exhaust pipeline 17. By controlling the first branch 21 and the second branch 22 to be turned on or off, the variable capacity can be adjusted to control the single-cylinder or double-cylinder operation of the variable capacity compressor 11. At the same time, by controlling the air supply pipeline 30 of the heat pump system to be turned on or off, the air supply and enthalpy increase function of the variable capacity compressor 11 can be controlled to be turned on or off. The heat pump system is also provided with a bypass pipeline 40, which is arranged in parallel with the first throttle valve 13 and the flasher 14. By controlling the bypass pipeline 40 to be turned on or off, the number of throttling times can be further controlled. Therefore, the embodiments of the present disclosure can construct multiple working modes to adapt to the capacity requirements of the heat pump system under different operating conditions, so that the heat pump system can achieve efficient and energy-saving operation under various operating conditions, which is conducive to simultaneously meeting the wide range of capacity changes of the heat pump system and efficient operation under all operating conditions.

[0046] Optionally, combined Figure 2As shown, the variable capacity compressor 11 includes a housing, a motor and a body. A storage space is constructed in the housing. The motor is arranged in the storage space, and includes a motor rotor 1116 and a motor stator 1117. The body is arranged in the storage space, and includes a crankshaft 1115, and an upper bearing 1113, an upper roller (not shown in the figure), an upper cylinder 111, a partition 1110, a lower roller 1114, a lower cylinder 112, a lower bearing 1111 and a lower cover plate 1112 which are sequentially penetrated by the crankshaft 1115 from top to bottom. The motor stator 1117 is fixed in the storage space, and the motor rotor 1116 is connected to the crankshaft 1115. The upper roller cooperates with the upper cylinder 111, and the lower roller 1114 cooperates with the lower cylinder 112. In this way, the rotation of the motor rotor 1116 can drive the crankshaft 1115 to rotate, and then drive the upper roller in the upper cylinder 111 and the lower roller 1114 in the lower cylinder 112 to rotate. Through the eccentric rotation of the upper roller and the lower roller 1114, the upper cylinder 111 and the lower cylinder 112 finally realize the compression process of the refrigerant.

[0047] Optionally, the variable capacity compressor 11 is further provided with an exhaust port 1118 and an air intake port (not shown in the figure). The exhaust port 1118 is connected to the condenser 12 to form an exhaust pipeline 17. The air intake port is connected to the evaporator 16 to form an air intake pipeline 18. The air intake port includes an upper air intake port and a lower air intake port, the upper air intake port is provided in the upper cylinder, and the lower air intake port is provided in the lower cylinder. In this way, the refrigerant circulation can be completed through the exhaust pipeline 17 and the air intake pipeline 18 in the main circulation loop 10.

[0048] Optionally, combined Figure 3-6 As shown, the air supply port 114 is provided at the lower cylinder 112, and the variable capacity compressor further includes a one-way valve assembly 115. The one-way valve assembly 115 is provided on the lower cylinder 112 corresponding to the air supply port 114, and is used to limit the one-way flow of the refrigerant from the air supply pipeline 30 to the lower cylinder 112. In this way, the lower cylinder 112 can realize an independent air supply enthalpy injection function. And by providing the one-way valve assembly 115 at the outlet of the air supply port 114, the embodiment of the present disclosure can prevent the problem of liquid return from the air supply port of the variable capacity compressor 11, which is conducive to improving the reliability of air supply of the variable capacity compressor 11.

[0049] Optionally, the one-way valve assembly 115 includes a one-way valve disc 1151 and a one-way valve baffle 1152. The one-way valve disc 1151 is covered at the air supply port 114. The one-way valve baffle 1152 includes a connecting portion 11521 and a limiting portion 11522, wherein the connecting portion 11521 is disposed above the one-way valve disc 1151 and is fixedly connected to the one-way valve disc 1151, and the limiting portion 11522 is disposed above the one-way valve disc 1151 opposite to the air supply port 114, and a gap is formed between the lower end surface of the limiting portion 11522 and the one-way valve disc 1151 for limiting the opening of the one-way valve disc 1151. In this way, it can be ensured that when the one-way valve plate 1151 is opened, it can fully contact and limit the one-way valve baffle 1152, and form a certain opening gap to ensure that the refrigerant can flow unidirectionally into the lower cylinder 112 through the air supply pipeline 30, thereby ensuring the reliability of the one-way valve assembly 115 for air supply.

[0050] Optionally, the upper end surface of the one-way valve baffle 1152 is a plane, the lower end surface of the connecting portion 11521 is a plane, and the lower end surface of the limiting portion 11522 is an arc surface. In this way, it is considered that the excessive clearance volume of the variable capacity compressor 11 will directly affect the energy efficiency of the variable capacity compressor 11. The disclosed embodiment makes the upper end surface of the one-way valve baffle 1152 into a plane, which can ensure that the matching clearance between the upper end surface of the one-way valve baffle 1152 and the partition 1110 after assembly is minimized to reduce the clearance volume after matching. That is, the clearance volume of the variable capacity compressor 11 is reduced, which is beneficial to improving the energy efficiency of the variable capacity compressor 11. By making the lower end surface of the one-way valve baffle 1152 located at the limiting portion 11522 into an arc surface, it can be ensured that when the one-way valve plate 1151 is opened, it can be fully contacted and limited with the one-way valve baffle 1152, and a certain opening gap can be formed to ensure that the refrigerant can flow unidirectionally into the lower cylinder 112 through the air supply pipeline 30, thereby ensuring the reliability of the one-way valve assembly 115 for air supply.

[0051] Optionally, a one-way valve seat 1153 is provided on the lower cylinder 112, a partition 1110 is sandwiched between the upper cylinder 111 and the lower cylinder 112, the one-way valve seat 1153 and the partition 1110 form a receiving cavity, and the one-way valve assembly 115 is arranged in the receiving cavity. The distance between the upper end surface of the one-way valve baffle 1152 and the upper end surface of the lower cylinder 112 is h, and h≤0.1mm. In this way, it is considered that the excessive clearance volume of the variable volume compressor 11 will directly affect the energy efficiency of the variable volume compressor 11. In the embodiment of the present disclosure, the one-way valve assembly 115 is arranged in the receiving cavity between the one-way valve seat 1153 and the partition 1110, and the matching clearance between the upper end surface of the one-way valve baffle 1152 and the partition 1110 after assembly is controlled to be no more than 0.1mm, so as to reduce the clearance volume as much as possible under the premise of ensuring the reliability of the one-way valve assembly 115 replenishing gas, thereby facilitating the improvement of the energy efficiency of the variable volume compressor 11.

[0052] Preferably, the distance h between the upper end surface of the one-way valve baffle 1152 and the upper end surface of the lower cylinder 112 is 0.07 mm, which can reduce the clearance volume as much as possible under the premise of ensuring the reliability of the one-way valve assembly 115 to replenish the gas, thereby facilitating the improvement of the energy efficiency of the variable capacity compressor 11. h can also be adjusted in combination with the specific design requirements of the variable capacity compressor 11, and can also be set to any other reasonable value such as 0.02 mm or 0.09 mm.

[0053] Optionally, when the one-way valve assembly 115 is disposed in the accommodating chamber, the remaining volume in the accommodating chamber is V 0 , 0.02mL≤V 0 ≤1mL. Thus, when the one-way valve assembly 115 is disposed in the accommodation cavity between the one-way valve seat 1153 and the partition 1110, the embodiment of the present disclosure controls the one-way valve assembly 115 and the one-way valve seat 1153 to form a clearance volume between 0.02mL and 1mL with the partition 1110. On the one hand, it can avoid that when V 0 When the clearance volume of the variable capacity compressor 11 is greater than 1 mL, the excessive clearance volume of the variable capacity compressor 11 will directly affect the energy efficiency of the variable capacity compressor 11. 0 When it is less than 0.02 mL, the residual volume in the accommodating chamber is too small, resulting in obstruction of the circulation of the refrigerant, thereby affecting the reliability of the air supply pipeline 30 to supply air to the lower cylinder 112 .

[0054] Preferably, when the one-way valve assembly 115 is disposed in the accommodating chamber, the remaining volume V in the accommodating chamber is 0 The pressure is 0.7 mL, which can better balance the reliability of air replenishment through the one-way valve assembly 115 and the energy efficiency of the variable capacity compressor 11. 0 It can also be adjusted in combination with the specific design requirements of the variable capacity compressor 11, and can also be set to any other reasonable value such as 0.2mL or 0.9mL.

[0055] Optionally, the one-way valve assembly 115 further includes a one-way valve screw 1154. The one-way valve screw 1154 sequentially fixes the connection portion 11521 of the one-way valve plate 1151 and the one-way valve baffle 1152 on the one-way valve seat 1153. In this way, it can be ensured that the refrigerant can flow into the lower cylinder 112 more stably, so as to further improve the reliability of air replenishment through the one-way valve assembly 115.

[0056] Optionally, a slide groove 116 is provided on the side of the lower cylinder 112 facing the variable capacity port 113, and the variable capacity compressor 11 further includes a variable capacity slide 117, a pin 118 and an elastic member 119. The variable capacity slide 117 is provided in the slide groove 116, and a groove 1171 is provided on the variable capacity slide 117. The pin 118 is movably provided below the variable capacity slide 117, and a protrusion 1181 is provided on one end of the pin 118 facing the variable capacity slide 117, and the protrusion 1181 is adapted to the groove 1171 of the variable capacity slide 117. The elastic member 119 is connected to the pin 118 so that the pin 118 can move between a free position and a clamping position, wherein when the pin 118 moves to the free position, the protrusion 1181 of the pin 118 is engaged with the groove 1171 of the variable capacity slide 117 to limit the displacement of the variable capacity slide 117. In this way, the variable capacity port 113 is connected to the cavity at the tail of the variable capacity slide 117. Since the variable capacity pipeline 20 is divided into a first branch 21 connected to the suction pipeline 18 and a second branch 22 connected to the exhaust pipeline 17, by controlling the first branch 21 and the second branch 22 to be connected or disconnected, the embodiment of the present disclosure can control the suction low pressure or the exhaust high pressure to flow to the cavity at the tail of the variable capacity slide 117, so that the variable capacity can be adjusted to realize the single-cylinder or double-cylinder operation of the variable capacity compressor 11.

[0057] When the first branch 21 is turned on and the second branch 22 is turned off, the cavity at the tail of the variable capacity slide 117 is connected to the suction pipeline 18 of the variable capacity compressor 11. At this time, the tail and head of the variable capacity slide 117 are both suction low pressure, and there is no pressure difference between the front and the back. The upward elastic force of the elastic member 119 on the pin 118 is greater than the downward pressure of the suction low pressure, so the pin 118 moves upward under the action of the elastic member 119. When the pin 118 moves to the free position, the protrusion 1181 at the upper end of the pin 118 is engaged with the groove 1171 at the lower end of the variable capacity slide 117, thereby limiting the displacement of the variable capacity slide 117. At this time, the variable capacity slide 117 is separated from the lower roller 1114, the lower cylinder 112 stops working, and the variable capacity compressor 11 operates with a single cylinder.

[0058] When the second branch 22 is turned on and the first branch 21 is turned off, the cavity at the tail of the variable capacity slide 117 is connected to the exhaust pipe 17 of the variable capacity compressor 11. At this time, the tail cavity of the variable capacity slide 117 is the exhaust high pressure, while the head is the suction low pressure, forming a high pressure difference between the front and the back, and the variable capacity slide 117 has a tendency to slide toward the lower roller 1114. At this time, the downward pressure of the exhaust high pressure is greater than the upward elastic force of the elastic member 119 on the pin 118, so the pin 118 overcomes the elastic force of the elastic member 119 and moves downward under the action of the exhaust high pressure. When the pin 118 moves to the clamping position, the protrusion 1181 at the upper end of the pin 118 is separated from the groove 1171 at the lower end of the variable capacity slide 117. At this time, the variable capacity slide 117 slides toward the lower roller 1114 until it abuts against it, and the lower cylinder 112 starts to work, and the variable capacity compressor 11 operates with two cylinders.

[0059] Optionally, the lower bearing 1111 is configured with a pin hole, and the pin 118 is disposed in the pin hole. The elastic member 119 is a pin spring, and the elastic member 119 is fixedly connected to the lower cover plate 1112. In this way, under the action of the unbalanced forces at the upper and lower ends, the pin 118 can move up and down between the free position and the clamping position in the pin hole to achieve contact or separation with the variable capacity slide 117, thereby completing the switching of the variable capacity compressor 11 to single-cylinder or double-cylinder operation.

[0060] Optionally, the displacement of the upper cylinder is V 1 , the displacement of the lower cylinder is V 2 , 0.5≤V 1 / V 2 ≤0.8. Thus, when the variable capacity compressor 11 is outputting at a low capacity, the embodiment of the present disclosure can make the speed of the single cylinder run at an appropriate frequency to ensure that the volumetric efficiency and electrical efficiency of the variable capacity compressor 11 are at a good level. 1 / V 2 When it is less than 0.5, the displacement ratio of the upper and lower cylinders is too small, resulting in a high operating frequency of the variable capacity compressor 11 and a decrease in motor efficiency. 1 / V 2 When it is greater than 0.8, the ratio of the upper and lower cylinder displacements is too large, resulting in a low frequency of excess capacity, and both the volumetric efficiency of the compressor and the electrical efficiency of the motor are low.

[0061] Preferably, the ratio V of the displacement of the upper cylinder to the displacement of the lower cylinder is 1 / V 2 is 0.6, which can better balance the volumetric efficiency and electrical efficiency of the variable capacity compressor 11. 1 / V 2 It can also be adjusted in combination with specific design requirements of the variable capacity compressor 11, and can also be set to any other reasonable value such as 0.55 or 0.7.

[0062] Optionally, combined Figure 7 As shown, the heat pump system further includes a third branch 50. One end of the third branch 50 is connected to the air supply pipeline 30, and the other end is connected to the variable volume pipeline 20. The third branch 50 is provided with a fifth control valve 65.

[0063] The tail of the variable capacity slide 117 in the lower cylinder 112 is a sealed cavity, and the gap between the variable capacity slide 117 and the slide slot 116 is sealed as an oil-gas mixture. Considering that the exhaust high pressure is passed through the cavity when the lower cylinder 112 is working, the suction side of the lower cylinder 112 is the suction low pressure, that is, the exhaust high pressure at the tail of the variable capacity slide 117 and the suction low pressure at its head constitute a high pressure difference. When the lower cylinder 112 is running at a high pressure difference, the high pressure at the tail of the variable capacity slide 117 will leak to the suction side of the cylinder through the gap of the slide slot 116, resulting in a decrease in the volumetric efficiency of the lower cylinder 112 and an increase in power consumption. In this case, the embodiment of the present disclosure can control the conduction or disconnection of the third branch 50 to control the medium pressure of the supplementary gas to the tail of the variable capacity slide 17, so that the gas pressure difference between the tail and the head of the variable capacity slide 117 is relatively reduced. Therefore, the embodiment of the present disclosure can reduce the leakage of the slide slot 116, which is conducive to improving the energy efficiency of the variable capacity compressor 11.

[0064] Optionally, a variable capacity tank 23 is provided on the variable capacity pipeline 20. In this way, the variable capacity tank 23 can reduce the pressure pulsation in the variable capacity pipeline 20, and can separate the refrigerant in the variable capacity pipeline 20 from gas and liquid, thereby preventing the liquid refrigerant from directly entering the variable capacity compressor 11 to cause liquid hammer, which is beneficial to improving the service life of the variable capacity compressor 11.

[0065] Optionally, an air supply tank 31 is provided on the air supply pipeline 30. In this way, the air supply tank 31 can reduce the pressure pulsation in the air supply pipeline 30, and can separate the refrigerant in the air supply pipeline 30 from gas and liquid, thereby preventing the liquid refrigerant from directly entering the variable capacity compressor 11 to cause liquid hammer, which is beneficial to improving the service life of the variable capacity compressor 11.

[0066] Optionally, a liquid separator 19 is provided on the suction line 18. In this way, the liquid separator 19 can reduce the pressure pulsation in the suction line 18 and can separate the refrigerant in the suction line 18 from gas and liquid, thereby preventing the liquid refrigerant from directly entering the variable capacity compressor 11 to cause liquid hammer, which is beneficial to improving the service life of the variable capacity compressor 11.

[0067] Optionally, a first pressure sensor 71 is provided on the exhaust line 17, and is configured to obtain the exhaust pressure of the variable capacity compressor 11. A second pressure sensor 72 is provided on the suction line 18, and is configured to obtain the suction pressure of the variable capacity compressor 11. In this way, the embodiment of the present disclosure can monitor the exhaust pressure and suction pressure of the variable capacity compressor 11, so as to analyze the actual operating conditions of the heat pump system, which is conducive to matching the most suitable working mode to adapt to the capacity requirements of the heat pump system under different working conditions.

[0068] Optionally, the first control valve 61, the second control valve 62, the third control valve 63, the fourth control valve 64, and the fifth control valve 65 are solenoid valves. In this way, by controlling the opening and closing states of the solenoid valves, the embodiment of the present disclosure can control the corresponding pipelines to be connected or disconnected to complete the switching of the working mode of the heat pump system.

[0069] Based on the above heat pump system, combined with Figure 8 As shown, the embodiment of the present disclosure provides a control method for a heat pump system, comprising:

[0070] S801: The processor obtains operating parameters of the heat pump system.

[0071] S802: The processor determines an operating mode of the heat pump system according to operating parameters of the heat pump system.

[0072] S803: The processor configures the opening and closing states of each control valve according to the working mode of the heat pump system.

[0073] By adopting the control for the heat pump system provided by the embodiment of the present disclosure, it is possible to construct a variety of working modes through the corresponding pipeline design to adapt to the capacity requirements of the heat pump system under different working conditions. On this basis, the embodiment of the present disclosure can analyze the actual operating conditions of the heat pump system by obtaining the operating parameters of the heat pump system, and can match the most suitable working mode accordingly. Then, by adjusting the opening and closing states of the corresponding control valves on the first branch, the second branch, the air supply pipeline and the bypass pipeline, the corresponding pipelines can be controlled to be connected or disconnected, thereby realizing intelligent control of the heat pump system to enter the most suitable working mode, so that the heat pump system can achieve efficient and energy-saving operation under various working conditions, which is conducive to simultaneously meeting the wide range of capacity changes of the heat pump system and efficient operation of all working conditions.

[0074] Optionally, the operating parameters of the heat pump system include the operating frequency, exhaust pressure and suction pressure of the variable capacity compressor. In this way, by monitoring the above operating parameters, the embodiment of the present disclosure can analyze the actual operating conditions of the heat pump system, which is conducive to matching the most suitable working mode to adapt to the capacity requirements of the heat pump system under different working conditions.

[0075] Optionally, the processor determines the operating mode of the heat pump system based on the operating parameters of the heat pump system, including: when the operating frequency of the variable capacity compressor is less than a preset operating frequency, and / or the pressure difference between the exhaust pressure and the suction pressure of the variable capacity compressor is less than or equal to a first pressure difference, the processor determines that the operating mode of the heat pump system is a single-cylinder mode; or, when the operating frequency of the variable capacity compressor is greater than or equal to the preset operating frequency, and the pressure difference between the exhaust pressure and the suction pressure of the variable capacity compressor is greater than the first pressure difference, the processor determines that the operating mode of the heat pump system is a dual-cylinder mode.

[0076] In this way, when the operating frequency of the variable capacity compressor is less than the preset operating frequency, and / or the pressure difference between the exhaust pressure and the suction pressure of the variable capacity compressor is less than or equal to the first pressure difference, the variable capacity compressor is in a low-load and low-capacity output state regardless of whether the heat pump system is operating in a cooling or heating condition. If the operating frequency of the variable capacity compressor is too low, its motor efficiency and volumetric efficiency will be greatly attenuated, resulting in a decrease in the energy efficiency of the entire heat pump system. At this time, the difference between the exhaust pressure and the suction pressure of the variable capacity compressor is small. If the method of two throttling and intermediate air replenishment is adopted, the intermediate pressure is between the suction pressure and the exhaust pressure, and the variable capacity compressor's air replenishment medium pressure is relatively difficult to control. If the air replenishment medium pressure is controlled too high, it will cause the air replenishment to carry liquid, which will bring great risks to the reliability of the compressor. If the air replenishment medium pressure is controlled too low, it will cause the air replenishment to fail, and the air replenishment enthalpy increase will become worse. Under this condition, it is difficult to balance the opening of the two throttle valves by two throttling, and the complex throttle valve control will waste a certain amount of electric energy, resulting in a relatively low energy efficiency of the heat pump system. Therefore, in order to adapt to the working conditions of the heat pump system with light load and small pressure difference, the disclosed embodiment enables the heat pump system to operate in single-cylinder mode, and the heat pump system turns off the air replenishment function to perform a throttling operation. At this time, the exhaust gas of the variable capacity compressor only needs one throttling after condensation by the condenser to meet the refrigerant evaporation demand. At the same time, since the upper and lower cylinders of the variable capacity compressor are designed with large and small displacements, at this time, only the upper cylinder of the compressor is running, and the operating displacement of the compressor is small. The operating frequency of the variable capacity compressor can be increased as much as possible with the same cooling output. Therefore, the single-cylinder mode can ensure the high volumetric efficiency and high electrical efficiency of the variable capacity compressor when operating at low load.

[0077] When the operating frequency of the variable capacity compressor is greater than or equal to the preset operating frequency, and the pressure difference between the exhaust pressure and the suction pressure of the variable capacity compressor is greater than the first pressure difference, the variable capacity compressor is in a high-load and high-capacity output state regardless of whether the heat pump system is operating in a cooling or heating condition. At this time, in order to ensure that the variable capacity compressor can output efficiently, the embodiment of the present disclosure enables the heat pump system to operate in a dual-cylinder mode, and the upper and lower cylinders of the variable capacity compressor work simultaneously, thereby being able to meet the capacity requirements of the heat pump system.

[0078] Optionally, the processor determines that the operating mode of the heat pump system is a two-cylinder mode, including: when the pressure ratio of the exhaust pressure to the suction pressure of the variable capacity compressor is less than or equal to a preset pressure ratio, the processor determines that the operating mode of the heat pump system is a two-cylinder normal mode; or, when the pressure ratio of the exhaust pressure to the suction pressure of the variable capacity compressor is greater than a preset pressure ratio, the processor determines that the operating mode of the heat pump system is a two-cylinder enthalpy increase mode.

[0079] In this way, when the variable capacity compressor is in a high-load and high-capacity output state, the embodiment of the present disclosure enables the heat pump system to operate in a dual-cylinder mode to meet the capacity requirements of the heat pump system. On this basis, the embodiment of the present disclosure further compares the pressure ratio of the exhaust pressure and the suction pressure of the variable capacity compressor to analyze the exhaust temperature and actual capacity output of the variable capacity compressor at this time, thereby further optimizing the working mode of the heat pump system.

[0080] When the pressure ratio of the exhaust pressure to the suction pressure of the variable volume compressor is less than or equal to the preset pressure ratio, the ratio and difference of the exhaust pressure to the suction pressure of the variable volume compressor are not large, and there is no need to replenish the variable volume compressor, and its exhaust temperature and operating capacity can still be maintained at a good level. Therefore, the disclosed embodiment enables the heat pump system to operate in a dual-cylinder normal mode, at which time the air replenishment function is turned off, and the heat pump system only performs a throttling operation once. The dual-cylinder normal mode can thus enable the heat pump system to operate efficiently within the operating range of large capacity and low pressure ratio, and can solve the problem that the existing heat pump system is difficult to control the low-pressure ratio two-throttling air replenishment pressure.

[0081] When the pressure ratio of the exhaust pressure to the suction pressure of the variable capacity compressor is greater than the preset pressure ratio, the variable capacity compressor operates at a high pressure ratio. At this time, the suction density of the variable capacity compressor is reduced, the suction volume is reduced, and the exhaust temperature is too high. Excessive exhaust temperature will have an adverse effect on the reliability of the compressor motor and the compressor pump body parts, and may cause irreversible phenomena such as demagnetization of the motor magnet and wear of the pump body parts, and the compressor capacity will be significantly attenuated. At this time, it is necessary to increase the suction volume of the variable capacity compressor through intermediate air replenishment and reduce the exhaust temperature of the variable capacity compressor, so as to adapt to the high pressure ratio capacity and energy efficiency requirements. Therefore, the embodiment of the present disclosure enables the heat pump system to operate in a dual-cylinder enthalpy increase mode. At this time, the heat pump system turns on the air replenishment function, and the exhaust of the variable capacity compressor is throttled twice after being condensed by the condenser to meet the intermediate air replenishment and evaporator refrigerant requirements. The lower cylinder of the variable capacity compressor performs independent air replenishment work. At this time, the dual-cylinder enthalpy increase mode can enable the heat pump system to operate efficiently within the operating range of large capacity and high pressure ratio, and can solve the problem of insufficient operating capacity of the heat pump system under high pressure ratio operating conditions and excessive exhaust temperature.

[0082] Optionally, the processor determines that the working mode of the heat pump system is a two-cylinder enthalpy increase mode, including: when the pressure difference between the exhaust pressure and the suction pressure of the variable displacement compressor is less than the second pressure difference, the processor determines that the working mode of the heat pump system is a first two-cylinder enthalpy increase mode; or when the pressure difference between the exhaust pressure and the suction pressure of the variable displacement compressor is greater than or equal to the second pressure difference, the processor determines that the working mode of the heat pump system is a second two-cylinder enthalpy increase mode. The second pressure difference is greater than the first pressure difference.

[0083] In this way, when the heat pump system is in the operating range of large capacity and high pressure ratio, the embodiment of the present disclosure enables the heat pump system to operate in a dual-cylinder enthalpy increase mode to solve the problem of insufficient operating capacity and excessive exhaust temperature in the high pressure ratio operating condition of the heat pump system, which is conducive to the efficient operation of the heat pump system. On this basis, the embodiment of the present disclosure again compares the pressure difference between the exhaust pressure and the suction pressure of the variable capacity compressor to analyze the leakage of the sliding vane groove when the lower cylinder is operating at a high pressure difference, so as to further optimize the working mode of the heat pump system.

[0084] When the pressure difference between the exhaust pressure and the suction pressure of the variable capacity compressor is less than the second pressure difference, the pressure difference between the tail and the head of the variable capacity vane is relatively small. At this time, the leakage of the vane slot is not much, so there is no need to pass the medium pressure of the air to the tail of the variable capacity vane. Therefore, the disclosed embodiment enables the heat pump system to operate in the first double-cylinder enthalpy increase mode, at which time the tail of the variable capacity vane is passed through the exhaust high pressure, thereby avoiding the variable capacity vane and the lower roller from separating and generating impact noise due to the small pressure difference between the tail and the head of the variable capacity vane. At this time, the first double-cylinder enthalpy increase mode can make the heat pump system operate efficiently within the operating range of large capacity and high pressure ratio under the premise that the leakage of the vane slot is not much, and can solve the problems of insufficient operating capacity of the heat pump system under high pressure ratio conditions, excessive exhaust temperature and impact noise.

[0085] When the pressure difference between the exhaust pressure and the suction pressure of the variable displacement compressor is greater than or equal to the second pressure difference, the pressure difference between the tail and head gas of the variable displacement vane is large, and the leakage of the vane slot increases significantly, that is, the high pressure at the tail of the variable displacement vane will leak to the suction side of the cylinder through the gap of the vane slot, resulting in a decrease in the volumetric efficiency of the lower cylinder and an increase in power consumption. Therefore, it is necessary to reduce the pressure difference between the tail and head gas of the variable displacement vane to control the leakage of the vane slot. To this end, the disclosed embodiment enables the heat pump system to operate in the second double-cylinder enthalpy increase mode, at which the tail of the variable displacement vane switches from the high pressure of exhaust to the medium pressure of supplementary air, thereby reducing the pressure difference between the tail and head of the variable displacement vane, greatly reducing the leakage of the vane slot, and being conducive to improving the energy efficiency of the variable displacement compressor. Thus, the second double-cylinder enthalpy increase mode can enable the heat pump system to operate efficiently within the operating range of large capacity, high pressure ratio and high pressure difference, and can solve the problems of insufficient operating capacity of the heat pump system under high pressure ratio and high pressure difference operating conditions, high exhaust temperature and variable displacement cylinder leakage.

[0086] Optionally, the processor configures the opening and closing states of each control valve according to the operating mode of the heat pump system, including: when the operating mode of the heat pump system is the single-cylinder mode, controlling the first control valve and the fourth control valve to open, and controlling the second control valve, the third control valve and the fifth control valve to close.

[0087] In this way, when the operating frequency of the variable capacity compressor is less than the preset operating frequency, and / or the pressure difference between the exhaust pressure and the suction pressure of the variable capacity compressor is less than or equal to the first pressure difference, the variable capacity compressor is in a low-load small capacity output state, and the disclosed embodiment enables the heat pump system to operate in a single-cylinder mode, and closes the air replenishment function to ensure the high volumetric efficiency and high electrical efficiency of the variable capacity compressor when operating at low load. Specifically, the disclosed embodiment opens the first control valve to conduct the first branch, and the suction low pressure is passed to the tail of the variable capacity slide, and at this time there is no obvious pressure difference between the tail and the head of the variable capacity slide. Under the action of the elastic member, the pin is engaged with the variable capacity slide, limiting its contact with the lower roller, so that the lower cylinder stops working, and the variable capacity compressor operates in a single cylinder. However, since the upper and lower cylinders of the variable capacity compressor are designed for large and small displacements, at this time, the variable capacity compressor only operates in the upper cylinder, and the operating displacement of the compressor is small. The same cooling output can increase the operating frequency of the variable capacity compressor as much as possible, so that the high volumetric efficiency and high electrical efficiency of the variable capacity compressor when operating at low load can be guaranteed. At the same time, the embodiment of the present disclosure opens the fourth control valve to conduct the bypass line, so that the first throttle valve and the flasher are bypassed. At this time, the heat pump system only performs one throttling, and the exhaust gas of the variable capacity compressor can meet the refrigerant evaporation demand after being condensed by the condenser and throttling once, and can solve the problem that the low pressure difference of the existing heat pump system is difficult to control the double throttling gas replenishment pressure, which is conducive to improving the energy efficiency of the heat pump system.

[0088] Optionally, the processor configures the opening and closing states of each control valve according to the operating mode of the heat pump system, including: when the operating mode of the heat pump system is the dual-cylinder normal mode, controlling the second control valve and the fourth control valve to open, and controlling the first control valve, the third control valve and the fifth control valve to close.

[0089] In this way, when the operating frequency of the variable capacity compressor is greater than or equal to the preset operating frequency, and the pressure difference between the exhaust pressure and the suction pressure of the variable capacity compressor is greater than the first pressure difference, and the pressure ratio between the exhaust pressure and the suction pressure of the variable capacity compressor is less than or equal to the preset pressure ratio, the heat pump system is in the working range of large capacity and low pressure ratio, and the embodiment of the present disclosure makes the heat pump system operate in a double-cylinder conventional mode, and closes the air replenishment function to meet the capacity requirements of the heat pump system. Specifically, the embodiment of the present disclosure opens the second control valve to conduct the second branch, and passes the exhaust high pressure to the tail of the variable capacity slide, at which time the tail of the variable capacity slide and the head form a high pressure difference. The variable capacity slide slides toward the lower roller until it abuts against it, so that the lower cylinder starts to work, and the variable capacity compressor operates with two cylinders, thereby ensuring the capacity of the variable capacity compressor to output efficiently. At the same time, the embodiment of the present disclosure opens the fourth control valve to conduct the bypass line, so that the first throttle valve and the flasher are bypassed. At this time, the heat pump system only performs one throttling, and the exhaust of the variable capacity compressor is condensed by the condenser and then throttled once to meet the refrigerant evaporation requirements. At this time, the heat pump system can operate efficiently within the operating range of large capacity and low pressure ratio, and can solve the problem that the low-pressure ratio double throttling air supply pressure of the existing heat pump system is difficult to control, which is beneficial to improving the energy efficiency of the heat pump system.

[0090] Optionally, the processor configures the opening and closing states of each control valve according to the operating mode of the heat pump system, including: when the operating mode of the heat pump system is the first dual-cylinder enthalpy increase mode, controlling the second control valve and the third control valve to open, and controlling the first control valve, the fourth control valve and the fifth control valve to close.

[0091] In this way, when the operating frequency of the variable capacity compressor is greater than or equal to the preset operating frequency, and the pressure difference between the exhaust pressure and the suction pressure of the variable capacity compressor is greater than the first pressure difference and less than the second pressure difference, and the pressure ratio between the exhaust pressure and the suction pressure of the variable capacity compressor is greater than the preset pressure ratio, the heat pump system is in the operating range of large capacity and high pressure ratio, and the embodiment of the present disclosure enables the heat pump system to operate the first double-cylinder enthalpy increase mode to enable the heat pump system to operate efficiently. Specifically, the embodiment of the present disclosure opens the second control valve to conduct the second branch, and the exhaust high pressure is passed to the tail of the variable capacity slide. At this time, the tail of the variable capacity slide and the head form a high pressure difference. The variable capacity slide slides toward the lower roller until it abuts against it, so that the lower cylinder starts to work, and the variable capacity compressor operates with two cylinders, thereby ensuring that the capacity of the variable capacity compressor can be output efficiently. At the same time, the embodiment of the present disclosure opens the third control valve to conduct the air supply pipeline, so that the air supply enthalpy increase function can be turned on. At this time, the exhaust gas of the variable capacity compressor is throttled twice after being condensed by the condenser to meet the needs of intermediate air supply and evaporator refrigerant, and the lower cylinder of the variable capacity compressor performs independent air supply. At this time, the heat pump system can operate efficiently within the operating range of large capacity and high pressure ratio, and can solve the problem of insufficient operating capacity of the heat pump system under high pressure ratio conditions and excessive exhaust temperature.

[0092] Optionally, the processor configures the opening and closing states of each control valve according to the operating mode of the heat pump system, including: when the operating mode of the heat pump system is the second two-cylinder enthalpy increase mode, controlling the third control valve and the fifth control valve to open, and controlling the first control valve, the second control valve and the fourth control valve to close.

[0093] In this way, when the operating frequency of the variable capacity compressor is greater than or equal to the preset operating frequency, and the pressure difference between the exhaust pressure and the suction pressure of the variable capacity compressor is greater than or equal to the second pressure difference, and the pressure ratio between the exhaust pressure and the suction pressure of the variable capacity compressor is greater than the preset pressure ratio, the heat pump system is in the operating range of large capacity, high pressure ratio and high pressure difference, and the embodiment of the present disclosure enables the heat pump system to operate the second double-cylinder enthalpy increase mode to reduce the leakage of the vane slot, which is beneficial to improve the energy efficiency of the variable capacity compressor. Specifically, the embodiment of the present disclosure opens the fifth control valve to conduct the third branch, and passes the air supplement medium pressure to the tail of the variable capacity vane. At this time, the tail of the variable capacity vane and the head form a certain pressure difference to ensure that the variable capacity compressor can maintain double cylinder operation. And it can relatively reduce the gas pressure difference between the tail and the head of the variable capacity vane, greatly reduce the leakage of the vane slot, and is beneficial to improve the energy efficiency of the variable capacity compressor. At the same time, the embodiment of the present disclosure opens the third control valve to conduct the air supplement pipeline, so that the air supplement enthalpy increase function can be turned on. At this time, the exhaust gas of the variable capacity compressor is throttled twice after being condensed by the condenser to meet the needs of intermediate air supply and evaporator refrigerant, and the lower cylinder of the variable capacity compressor performs independent air supply. At this time, the heat pump system can operate efficiently within the operating range of large capacity, high pressure ratio and high pressure difference, and can solve the problems of insufficient operating capacity of the heat pump system under high pressure ratio and high pressure difference conditions, high exhaust temperature and leakage of the variable capacity cylinder.

[0094] Optionally, the preset operating frequency can be set in combination with the actual capacity of the variable capacity compressor. Preferably, the preset operating frequency is 50 Hz. The preset operating frequency can also be adjusted according to the external environmental conditions, and can also be set to any other reasonable value such as 45 Hz or 55 Hz.

[0095] Optionally, the first pressure difference can be set in combination with the actual capacity of the variable displacement compressor. Preferably, the first pressure difference is 0.5 MPa. The first pressure difference can also be adjusted according to the external environmental conditions, and can also be set to any other reasonable value such as 0.4 MPa or 0.6 MPa.

[0096] Optionally, the second pressure difference can be set in combination with the actual capacity of the variable displacement compressor. Preferably, the second pressure difference is 1.5 MPa. The second pressure difference can also be adjusted according to the external environmental conditions, and can also be set to any other reasonable value such as 1.4 MPa or 1.6 MPa.

[0097] Optionally, the preset pressure ratio value can be set in combination with the actual capacity of the variable displacement compressor. Preferably, the preset pressure ratio value is 3.0. The preset pressure ratio value can also be adjusted according to the external environmental conditions, and can also be set to any other reasonable value such as 2.8 or 3.2.

[0098] Based on the above heat pump system, combined with Fig. 9 As shown, the embodiment of the present disclosure provides another control method for a heat pump system, comprising:

[0099] S901, the processor obtains the operating frequency, exhaust pressure and suction pressure of the variable capacity compressor.

[0100] S902: The processor determines the working mode of the heat pump system according to the operating frequency, exhaust pressure and suction pressure of the variable capacity compressor.

[0101] S903: The processor configures the opening and closing states of each control valve according to the working mode of the heat pump system.

[0102] By adopting the control for the heat pump system provided by the embodiment of the present disclosure, it is possible to construct a variety of working modes through the corresponding pipeline design to adapt to the capacity requirements of the heat pump system under different working conditions. On this basis, the embodiment of the present disclosure can analyze the actual operating state of the variable capacity compressor by obtaining the operating frequency, exhaust pressure and suction pressure of the variable capacity compressor, and can match the most suitable working mode accordingly. Then, by adjusting the opening and closing states of the corresponding control valves on the first branch, the second branch, the air supply pipeline and the bypass pipeline, the corresponding pipelines can be controlled to be connected or disconnected, thereby realizing intelligent control of the heat pump system to enter the most suitable working mode, so that the heat pump system can achieve efficient and energy-saving operation under various working conditions, which is conducive to simultaneously meeting the wide range of capacity changes of the heat pump system and efficient operation of all working conditions.

[0103] In the embodiments of the present disclosure, the specific execution methods of the relevant steps can be found in the above text and will not be further described here.

[0104] Based on the above heat pump system, combined with Fig.10 As shown, the embodiment of the present disclosure provides another control method for a heat pump system, comprising:

[0105] S1001: The processor obtains operating parameters of the heat pump system.

[0106] S1002: The processor determines an operating mode of the heat pump system according to operating parameters of the heat pump system.

[0107] S1003: The processor configures the opening and closing states of each control valve according to the working mode of the heat pump system.

[0108] S1004: The processor adjusts the opening of the first throttle valve and / or the second throttle valve according to the operating parameters of the heat pump system.

[0109] By adopting the control for the heat pump system provided by the embodiment of the present disclosure, a variety of working modes can be constructed through the corresponding pipeline design to adapt the capacity requirements of the heat pump system under different working conditions. On this basis, the embodiment of the present disclosure can analyze the actual operating conditions of the heat pump system by obtaining the operating parameters of the heat pump system, and can match the most suitable working mode accordingly. Then, by adjusting the opening and closing states of the corresponding control valves on the first branch, the second branch, the air supply pipeline and the bypass pipeline, the corresponding pipelines can be controlled to be connected or disconnected, thereby realizing intelligent control of the heat pump system to enter the most suitable working mode, so that the heat pump system can achieve efficient and energy-saving operation under various working conditions, which is conducive to simultaneously meeting the wide range of capacity changes of the heat pump system and the efficient operation of all working conditions. In addition, the embodiment of the present disclosure further adjusts the opening of the first throttle valve and / or the second throttle valve in combination with the operating parameters of the heat pump system to meet the intermediate air supply and refrigerant evaporation requirements, which is conducive to the stable operation of the heat pump system.

[0110] Optionally, the operating parameters of the heat pump system also include the exhaust temperature of the variable capacity compressor. In this way, by monitoring the exhaust temperature, the disclosed embodiment can determine the reliability of the operation of the variable capacity compressor, thereby further understanding the actual operating conditions of the heat pump system, which is conducive to timely correction of adverse conditions.

[0111] Optionally, the processor adjusts the opening of the first throttle valve and / or the second throttle valve according to the operating parameters of the heat pump system, including: the processor determines the target throttle valve from the first throttle valve and the second throttle valve according to the operating mode of the heat pump system; the processor adjusts the opening of the target throttle valve according to the exhaust temperature of the variable capacity compressor. In this way, the embodiment of the present disclosure can reasonably adjust the opening of the corresponding first throttle valve or second throttle valve in the actual operating mode of the heat pump system in combination with the exhaust temperature of the variable capacity compressor, so as to better meet the intermediate air supply and refrigerant evaporation requirements, which is conducive to the stable operation of the heat pump system.

[0112] Optionally, the processor determines the target throttle valve from the first throttle valve and the second throttle valve according to the working mode of the heat pump system, including: when the working mode of the heat pump system is a single-cylinder mode or a two-cylinder normal mode, the second throttle valve is determined to be the target throttle valve; or, when the working mode of the heat pump system is a first two-cylinder enthalpy increase mode or a second two-cylinder enthalpy increase mode, the first throttle valve is determined to be the target throttle valve. In this way, when the heat pump system operates in a single-cylinder mode or a two-cylinder normal mode, the heat pump system only throttles once, at which time the first throttle valve is bypassed, and the exhaust of the variable capacity compressor is condensed by the condenser and then throttled once to meet the refrigerant evaporation demand. Therefore, the embodiment of the present disclosure can adjust the opening of the second throttle valve according to the exhaust temperature adaptability of the variable capacity compressor, so as to reasonably control the exhaust temperature on the premise of meeting the refrigerant evaporation demand, which is conducive to the stable operation of the heat pump system. When the heat pump system operates in the first double-cylinder enthalpy increase mode or the second double-cylinder enthalpy increase mode, the exhaust gas of the variable capacity compressor is throttled twice after being condensed by the condenser to meet the intermediate air supply and evaporator refrigerant requirements. Therefore, the embodiment of the present disclosure can adjust the opening of the first throttle valve according to the exhaust gas temperature of the variable capacity compressor, so as to reasonably adjust the air supply medium pressure to avoid excessive control of the air supply medium pressure, resulting in liquid in the air supply, or excessive control of the air supply medium pressure, resulting in poor air supply enthalpy increase effect. Therefore, the embodiment of the present disclosure can reasonably reduce the exhaust gas temperature of the variable capacity compressor through intermediate air supply, which is conducive to the stable operation of the heat pump system.

[0113] Optionally, the processor adjusts the opening of the target throttle valve according to the exhaust temperature of the variable capacity compressor, including: when the exhaust temperature of the variable capacity compressor is greater than the preset exhaust temperature, increasing the opening of the target throttle valve. In this way, when the exhaust temperature of the variable capacity compressor is greater than the preset exhaust temperature, the excessively high exhaust temperature will have an adverse effect on the reliability of the compressor motor and the compressor pump body parts, and may cause irreversible phenomena such as demagnetization of the motor magnet and wear of the pump body parts, and the compressor capacity will be significantly attenuated. Therefore, the embodiment of the present disclosure can appropriately increase the opening of the first throttle valve or the second throttle valve, thereby increasing the system air supply volume and reducing the exhaust pressure, so as to reasonably reduce the exhaust temperature of the variable capacity compressor, which is conducive to improving the stability of the operation of the heat pump system.

[0114] Optionally, the preset exhaust temperature can be set in combination with the actual capacity of the variable capacity compressor. Preferably, the preset exhaust temperature is 95° C. The preset exhaust temperature can also be adjusted according to the external environmental conditions, and can also be set to any other reasonable value such as 94° C. or 96° C.

[0115] Combination Fig.11As shown, the embodiment of the present disclosure provides a control device 80 for a heat pump system, including a processor (processor) 81 and a memory (memory) 82. Optionally, the device may also include a communication interface (CommunicationInterface) 83 and a bus 84. Among them, the processor 81, the communication interface 83, and the memory 82 can communicate with each other through the bus 84. The communication interface 503 can be used for information transmission. The processor 81 can call the logic instructions in the memory 82 to execute the control method for the heat pump system of the above embodiment.

[0116] In addition, the logic instructions in the memory 82 described above may be implemented in the form of software functional units and when sold or used as independent products, may be stored in a computer-readable storage medium.

[0117] The memory 82 is a computer-readable storage medium that can be used to store software programs and computer executable programs, such as program instructions / modules corresponding to the method in the embodiment of the present disclosure. The processor 81 executes the function application and data processing by running the program instructions / modules stored in the memory 82, that is, the control method for the heat pump system in the above embodiment is implemented.

[0118] The memory 82 may include a program storage area and a data storage area, wherein the program storage area may store an operating system and an application required for at least one function; the data storage area may store data created according to the use of the terminal device, etc. In addition, the memory 82 may include a high-speed random access memory and may also include a non-volatile memory.

[0119] Combination Fig.12 As shown, an embodiment of the present disclosure provides an air conditioner, including: an air conditioner body 90, and the above-mentioned control device 80 for a heat pump system. The control device 80 for a heat pump system is installed on the air conditioner body 90. The installation relationship described here is not limited to placement inside the product, but also includes installation connections with other components of the product, 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 control device 80 for a heat pump system can be adapted to a feasible product body, thereby realizing other feasible embodiments.

[0120] An embodiment of the present disclosure provides a computer-readable storage medium storing computer-executable instructions, wherein the computer-executable instructions are configured to execute the above-mentioned control method for a heat pump system.

[0121] The computer-readable storage medium mentioned above may be a transient computer-readable storage medium or a non-transitory computer-readable storage medium.

[0122] The technical solution of the embodiment of the present disclosure can be embodied in the form of a software product, which is stored in a storage medium and includes one or more instructions for enabling a computer device (which may be a personal computer, a server, or a network device, etc.) to perform all or part of the steps of the method described in the embodiment of the present disclosure. The aforementioned storage medium may be a non-transient storage medium, including: 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, and other media that can store program codes, or a transient storage medium.

[0123] 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 changes. Unless explicitly required, separate components and functions are optional, and the order of operation may vary. The parts and features of some embodiments may be included in or replace the 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 the claims, unless the context clearly indicates, the singular forms of "a", "an" and "the" are intended to include plural forms as well. Similarly, the term "and / or" as used in this application refers to any and all possible combinations of listings containing one or more associated ones. In addition, when used in the present application, the term "comprise" and its variants "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 thereof. In the absence of further restrictions, the elements defined by the sentence "comprising a ..." do not exclude the presence of other identical elements in the process, method or device comprising the elements. In this article, each embodiment may focus on the differences from other embodiments, and the same and similar parts between the various embodiments may refer 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 refer to the description of the method part.

[0124] 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 for each specific application to implement the described functions, but such implementations should not be considered to exceed the scope of the embodiments of the present disclosure. The technicians may clearly understand that, for the convenience and simplicity of description, the specific working processes of the systems, devices and units described above may refer to the corresponding processes in the aforementioned method embodiments, and will not be repeated here.

[0125] 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 only schematic. For example, the division of the units can be only a logical function division. There may be other division methods in actual implementation, 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, which can be electrical, mechanical or other forms. The units described as separate components may or may not be physically separated, and the components displayed 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 according to actual needs to implement this embodiment. In addition, each functional unit in the embodiment of the present disclosure may be integrated in a processing unit, or each unit may exist physically alone, or two or more units may be integrated in one unit.

[0126] The flowchart and block diagram in the accompanying drawings show the possible architecture, function and operation of the system, method and computer program product according to the embodiment of the present disclosure. In this regard, each box in the flowchart or block diagram can represent a module, a program segment or a part of the code, and the module, the program segment or a part of the code contains one or more executable instructions for realizing the specified logical function. In some alternative implementations, the functions marked in the box can also occur in a different order from the order marked in the accompanying drawings. For example, two consecutive boxes can actually be executed substantially in parallel, and they can sometimes be executed in the opposite order, which can depend on the functions involved. In the description corresponding to the flowchart and the block diagram in the accompanying drawings, the operations or steps corresponding to different boxes can also occur in a different order from the order 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, and 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 functions or actions, or may be implemented by a combination of dedicated hardware and computer instructions.

Claims

1. A heat pump system, characterized in that: include: The main circulation loop includes a variable capacity compressor, a condenser, a first throttle valve, a flasher, a second throttle valve and an evaporator connected in sequence through a refrigerant pipeline to form a loop, the variable capacity compressor includes an upper cylinder and a lower cylinder, and the variable capacity compressor is provided with a variable capacity port and an air supply port; A variable capacity pipeline, one end of which is connected to the variable capacity port of the variable capacity compressor, and the other end of which is divided into a first branch and a second branch, the first branch being connected to the suction pipeline of the variable capacity compressor, the first branch being provided with a first control valve, the second branch being connected to the exhaust pipeline of the variable capacity compressor, the second branch being provided with a second control valve; An air supply pipeline, one end of which is connected to the air supply port of the variable capacity compressor, and the other end of which is connected to the flasher, and a third control valve is arranged on the air supply pipeline; The bypass pipeline has one end connected to the pipeline between the condenser and the first throttle valve, and the other end connected to the pipeline between the flasher and the second throttle valve. A fourth control valve is arranged on the bypass pipeline.

2. The heat pump system according to claim 1, characterized in that: The air supply port is arranged on the lower cylinder, and the variable capacity compressor also includes: The one-way valve assembly is arranged on the lower cylinder corresponding to the air supply port, and is used to limit the one-way flow of the refrigerant from the air supply pipeline to the lower cylinder.

3. The heat pump system according to claim 2, characterized in that: The one-way valve assembly includes a one-way valve disc and a one-way valve baffle. The one-way valve disc cover is arranged at the air supply port. The one-way valve baffle includes a connecting portion and a limiting portion. The connecting portion is arranged above the one-way valve disc and is fixedly connected to the one-way valve disc. The limiting portion is arranged above the one-way valve disc opposite to the air supply port, and the lower end surface of the limiting portion has a gap with the one-way valve disc for limiting the opening of the one-way valve disc.

4. The heat pump system according to claim 3, characterized in that: A one-way valve seat is provided on the lower cylinder, a partition is sandwiched between the upper cylinder and the lower cylinder, the one-way valve seat and the partition form an accommodating cavity, the one-way valve assembly is arranged in the accommodating cavity, and the distance between the upper end surface of the one-way valve baffle and the upper end surface of the lower cylinder is h, h≤0.1mm.

5. The heat pump system according to claim 4, characterized in that: When the one-way valve assembly is disposed in the accommodating chamber, the remaining volume in the accommodating chamber is V0, and 0.02 mL ≤ V0 ≤ 1 mL.

6. The heat pump system according to claim 1, characterized in that: A sliding vane groove is provided on the side of the lower cylinder facing the variable capacity port, and the variable capacity compressor also includes: The variable capacitance slide is arranged in the slide groove, and a groove is arranged on the variable capacitance slide; A pin is movably disposed below the variable capacitance slide, and a protrusion is disposed at one end of the pin facing the variable capacitance slide, and the protrusion is adapted to the groove of the variable capacitance slide; The elastic member is connected to the pin so that the pin can move between a free position and a clamping position, wherein when the pin moves to the free position, the protrusion of the pin is engaged with the groove of the variable-capacitance slide to limit the displacement of the variable-capacitance slide.

7. The heat pump system according to claim 1, characterized in that: The displacement of the upper cylinder is V1, the displacement of the lower cylinder is V2, 0.5≤V1 / V2≤0.

8.

8. The heat pump system according to any one of claims 1 to 7, characterized in that: The heat pump system also includes: The third branch has one end connected with the air supply pipeline and the other end connected with the variable volume pipeline. The third branch is provided with a fifth control valve.

9. The heat pump system according to any one of claims 1 to 7, characterized in that: The variable volume pipeline is provided with a variable volume tank; and / or, An air supply tank is provided on the air supply pipeline; and / or, A liquid distributor is provided on the suction pipeline.

10. A control method for a heat pump system, characterized in that: Applied to the heat pump system according to any one of claims 1 to 9, the method comprises: Obtain the operating frequency, exhaust pressure and suction pressure of the variable capacity compressor; Determine the working mode of the heat pump system according to the operating frequency, exhaust pressure and suction pressure of the variable capacity compressor; According to the working mode of the heat pump system, configure the opening and closing status of each control valve.

Images