CN112303955A

CN112303955A - Heat pump system, control method and control device thereof, air conditioning equipment and storage medium

Info

Publication number: CN112303955A
Application number: CN202011294377.4A
Authority: CN
Inventors: 杨智峰
Original assignee: Gree Electric Appliances Inc of Zhuhai
Current assignee: Gree Electric Appliances Inc of Zhuhai
Priority date: 2020-11-18
Filing date: 2020-11-18
Publication date: 2021-02-02

Abstract

The present invention relates to a heat pump system, a control method and a control device for the heat pump system, an air conditioner, and a storage medium. The heat pump system comprises a compressor, an indoor heat exchanger, a first outdoor heat exchanger, a second outdoor heat exchanger and a switching device, wherein a second port of the indoor heat exchanger is connected with a second port of the first outdoor heat exchanger through a first pipeline, a second port of the second outdoor heat exchanger is connected with a first pipeline through a second pipeline, the switching device is connected with an exhaust port and an air suction port of the compressor, a first port of the indoor heat exchanger, a first port of the first outdoor heat exchanger and a first port of the second outdoor heat exchanger, and is configured to control one of the first outdoor heat exchanger and the second outdoor heat exchanger and the indoor heat exchanger to be in a condenser mode and the other of the first outdoor heat exchanger and the second outdoor heat exchanger to be in an evaporator mode when the heat pump system is in a defrosting mode. Based on this, can improve the indoor temperature maladjustment problem in the defrosting process.

Description

Heat pump system, control method and control device thereof, air conditioning equipment and storage medium

Technical Field

The present invention relates to the field of air conditioning equipment technology, and in particular, to a heat pump system, a control method and a control device thereof, an air conditioning equipment, and a storage medium.

Background

Compared with an electric heating system, the heat pump system has the advantages of low energy consumption and the like, so that the heat pump technology is applied to various air-conditioning products, but the application of the heat pump technology is limited in some occasions with high requirements on temperature precision, such as a constant temperature and humidity machine and the like, and one important reason is that the conventional heat pump system has the problem of indoor temperature imbalance in the defrosting process.

Specifically, when the heat pump system is operated for heating, the outdoor heat exchanger frosts at certain outdoor temperatures, the performance of the outdoor heat exchanger is reduced due to frosting, an air duct of the heat exchanger is blocked, the heating capacity of the heat pump system is reduced, and when the heating capacity is reduced to a level that the indoor load demand cannot be met, the heat pump system needs to enter a defrosting mode. When the conventional heat pump system is in defrosting operation, heat required by defrosting of the outdoor heat exchanger is taken from indoors, the indoor heat exchanger is switched into an evaporator mode from a condenser mode, and the indoor heat exchanger can not be heated any more at the moment, so that the indoor temperature fluctuation is caused, the imbalance is caused, and the requirement on temperature control precision is difficult to meet.

Therefore, it is necessary to improve the problem of the imbalance of the indoor temperature of the heat pump system during the defrosting process, so as to improve the temperature control accuracy of the heat pump system, and make the application of the heat pump system in the high temperature control accuracy possible.

Disclosure of Invention

The embodiment of the invention provides a heat pump system, a control method and a control device thereof, air conditioning equipment and a storage medium, and aims to solve the problem of indoor temperature imbalance in a defrosting process.

The heat pump system provided by the invention comprises:

a compressor;

an indoor heat exchanger;

a first outdoor heat exchanger;

a second outdoor heat exchanger; and

the switching device controls the switching among the evaporator mode and the condenser mode of the indoor heat exchanger, the first outdoor heat exchanger and the second outdoor heat exchanger by controlling the on-off relation among the first port of the indoor heat exchanger, the first interface of the first outdoor heat exchanger and the first port of the second outdoor heat exchanger and the exhaust port and the suction port of the compressor;

a second port of the indoor heat exchanger is connected with a second port of the first outdoor heat exchanger through a first pipeline, and a second port of the second outdoor heat exchanger is connected with the first pipeline through a second pipeline;

the switching device is configured to control both the indoor heat exchanger and one of the first and second outdoor heat exchangers to be in the condenser mode and the other of the first and second outdoor heat exchangers to be in the evaporator mode when the heat pump system is in the defrosting mode.

In some embodiments, the switching device comprises:

the first switching valve comprises a first valve port, a second valve port, a third valve port and a fourth valve port, when the first valve port is communicated with one of the second valve port and the third valve port, the fourth valve port is communicated with the other of the second valve port and the third valve port, the first valve port is communicated with the exhaust port, the second valve port is communicated with the first port, the third valve port is connected with the first port through a third pipeline, and the fourth valve port is communicated with the suction port; and

and the second switching valve comprises a first switching port, a second switching port, a third switching port and a fourth switching port, when the first switching port is communicated with one of the second switching port and the third switching port, the fourth switching port is communicated with the other of the second switching port and the third switching port, the first switching port is communicated with the exhaust port, the second switching port is communicated with the first port, the third switching port is connected with the first port through a fourth pipeline, and the fourth switching port is communicated with the air suction port.

In some embodiments, the switching device further comprises:

the first valve is arranged on the third pipeline and used for controlling the on-off of the third pipeline; and

and the second valve is arranged on the fourth pipeline and used for controlling the on-off of the fourth pipeline.

In some embodiments, the first pipe and the second pipe are connected at a connection point, the heat pump system further comprising:

the first outdoor throttling element is arranged on the first pipeline and is positioned between the second interface and the connecting point; and

and the second outdoor throttling element is arranged on the second pipeline.

In some embodiments, the switching device is further configured to at least one of:

when the heat pump system is in a refrigeration mode, controlling the indoor heat exchanger to be in an evaporator mode, and controlling the first outdoor heat exchanger and the second outdoor heat exchanger to be in a condenser mode;

when the heat pump system is in a heating mode, the indoor heat exchanger is controlled to be in a condenser mode, and the first outdoor heat exchanger and the second outdoor heat exchanger are controlled to be in an evaporator mode.

In some embodiments, the compressor is located indoors or outdoors.

In some embodiments, the heat pump system further includes an inter-tube heat exchanger, a first flow passage and a second flow passage which can exchange heat with each other are provided in the inter-tube heat exchanger, and the first port are connected to the switching device through the first flow passage and the second flow passage, respectively, or the second port and the second port are connected to the indoor heat exchanger through the first flow passage and the second flow passage, respectively.

In some embodiments, the second port and the second port are connected to the indoor heat exchanger through a first flow passage and a second flow passage, respectively, and the first flow passage is located between the first outdoor throttle and the second port of the heat pump system.

In some embodiments, the inter-tube heat exchanger is located indoors or outdoors.

In some embodiments, the heat pump system further comprises a first outdoor fan and a second outdoor fan, the first outdoor fan and the first outdoor heat exchanger are located in the first air duct, the second outdoor fan and the second outdoor heat exchanger are located in the second air duct, and the first air duct and the second air duct are independently arranged.

The control method of the heat pump system provided by the invention is used for controlling the heat pump system of each embodiment, and comprises the following steps:

determining a target operation mode of the heat pump system;

and controlling the action of the switching device based on the target running mode.

In some embodiments, controlling the switching device action based on the target operating mode includes at least one of:

when the target operation mode is a defrosting mode, controlling the switching device to act, so that one of the first outdoor heat exchanger and the second outdoor heat exchanger and the indoor heat exchanger are both in a condenser mode, and the other of the first outdoor heat exchanger and the second outdoor heat exchanger is in an evaporator mode;

when the target operation mode is a refrigeration mode, controlling the switching device to act to enable the indoor heat exchanger to be in an evaporator mode and the first outdoor heat exchanger and the second outdoor heat exchanger to be in a condenser mode, or enabling one of the first outdoor heat exchanger and the second outdoor heat exchanger to be in the evaporator mode and the other to be in the condenser mode;

and when the target operation mode is a heating mode, controlling the switching device to act to enable the indoor heat exchanger to be in a condenser mode and the first outdoor heat exchanger and the second outdoor heat exchanger to be in an evaporator mode, or enabling one of the first outdoor heat exchanger and the second outdoor heat exchanger to be in the evaporator mode and the other one of the first outdoor heat exchanger and the second outdoor heat exchanger to be in the condenser mode.

In some embodiments, when the target operation mode is the defrosting mode, controlling the switching device to act so that one of the first outdoor heat exchanger and the second outdoor heat exchanger and the indoor heat exchanger are both in the condenser mode, and the other of the first outdoor heat exchanger and the second outdoor heat exchanger is in the evaporator mode includes at least one of:

when the target operation mode is a first defrosting mode, controlling the switching device to act, so that the second outdoor heat exchanger and the indoor heat exchanger are both in a condenser mode, and the first outdoor heat exchanger is in an evaporator mode;

and when the target operation mode is the defrosting mode, controlling the switching device to act, so that the first outdoor heat exchanger and the indoor heat exchanger are both in the condenser mode, and the second outdoor heat exchanger is in the evaporator mode.

determining a target operation mode of the heat pump system;

the first switching valve, the second switching valve, the first valve and the second valve are controlled to operate based on the target operation mode.

In some embodiments, controlling the first switching valve, the second switching valve, the first valve, and the second valve action based on the target operating mode includes at least one of:

when the target operation mode is a first defrosting mode, controlling a first valve port of a first switching valve to be communicated with a second valve port, controlling a third valve port to be communicated with a fourth valve port, controlling a first switching port of a second switching valve to be communicated with a third switching port, controlling a second switching port to be communicated with a fourth switching port, controlling the first valve to be closed, and opening a second valve, so that a second outdoor heat exchanger and an indoor heat exchanger are both in a condenser mode, and the first outdoor heat exchanger is in an evaporator mode;

when the target operation mode is a second defrosting mode, controlling the first valve port of the first switching valve to be communicated with the third valve port, controlling the second valve port to be communicated with the fourth valve port, controlling the first switching port of the second switching valve to be communicated with the second switching port, controlling the third switching port to be communicated with the fourth switching port, controlling the first valve to be opened, and controlling the second valve to be closed, so that the first outdoor heat exchanger and the indoor heat exchanger are both in a condenser mode, and the second outdoor heat exchanger is in an evaporator mode;

when the target operation mode is a first refrigeration mode, controlling a first valve port of a first switching valve to be communicated with a second valve port, controlling a third valve port to be communicated with a fourth valve port, controlling a first switching port of a second switching valve to be communicated with a second switching port, controlling a third switching port to be communicated with a fourth switching port, controlling the first valve and the second valve to be opened, enabling an indoor heat exchanger to be in an evaporator mode, and enabling a first outdoor heat exchanger and a second outdoor heat exchanger to be in a condenser mode;

when the target operation mode is a second refrigeration mode, controlling the first valve port of the first switching valve to be communicated with the second valve port, controlling the third valve port to be communicated with the fourth valve port, controlling the first switching port of the second switching valve to be communicated with the third switching port, controlling the second switching port to be communicated with the fourth switching port, controlling the first valve to be opened, and controlling the second valve to be closed, so that the indoor heat exchanger and the first outdoor heat exchanger are in an evaporator mode, and the second outdoor heat exchanger is in a condenser mode;

when the target operation mode is a third refrigeration mode, controlling the first valve port of the first switching valve to be communicated with the third valve port, controlling the second valve port to be communicated with the fourth valve port, controlling the first switching port of the second switching valve to be communicated with the second switching port, controlling the third switching port to be communicated with the fourth switching port, controlling the first valve to be closed, and opening the second valve, so that the indoor heat exchanger and the second outdoor heat exchanger are in an evaporator mode, and the first outdoor heat exchanger is in a condenser mode;

when the target operation mode is a first heating mode, controlling the first valve port of the first switching valve to be communicated with the third valve port, controlling the second valve port to be communicated with the fourth valve port, controlling the first switching port of the second switching valve to be communicated with the second switching port, controlling the third switching port to be communicated with the fourth switching port, controlling the first valve and the second valve to be opened, enabling the indoor heat exchanger to be in a condenser mode, and enabling the first outdoor heat exchanger and the second outdoor heat exchanger to be in an evaporator mode;

when the target operation mode is a second heating mode, controlling the first valve port of the first switching valve to be communicated with the third valve port, controlling the second valve port to be communicated with the fourth valve port, controlling the first switching port of the second switching valve to be communicated with the second switching port, controlling the third switching port to be communicated with the fourth switching port, controlling the first valve to be opened, and controlling the second valve to be closed, so that the indoor heat exchanger and the first outdoor heat exchanger are both in a condenser mode, and the second outdoor heat exchanger is in an evaporator mode;

when the target operation mode is a third heating mode, the first valve port of the first switching valve is controlled to be communicated with the second valve port, the third valve port of the first switching valve is controlled to be communicated with the fourth valve port, the first switching port of the second switching valve is controlled to be communicated with the third switching port, the second switching port of the second switching valve is controlled to be communicated with the fourth switching port, the first valve is controlled to be closed, the second valve is controlled to be opened, the indoor heat exchanger and the second outdoor heat exchanger are both in a condenser mode, and the first outdoor heat exchanger is in an evaporator mode.

The control device of the heat pump system comprises a memory and a processor coupled to the memory, wherein the processor is configured to execute the control method of each embodiment based on instructions stored in the memory.

The air conditioning equipment provided by the invention comprises the heat pump system and the control device of each embodiment.

The invention provides a computer-readable storage medium, which stores computer instructions, and the computer instructions are executed by a processor to execute the control method of each embodiment.

Based on the scheme of the invention, in the defrosting process, under the coordination of the switching device, the first outdoor heat exchanger and the second outdoor heat exchanger, the indoor heat exchanger can be always in the condenser mode without being switched to the evaporator mode, so that the indoor heat exchanger can still heat and output heating energy in the defrosting process, the indoor temperature fluctuation caused by the defrosting process can be reduced, and the problem of indoor temperature imbalance in the defrosting process can be effectively improved.

Other features of the present invention and advantages thereof will become apparent from the following detailed description of exemplary embodiments thereof, which proceeds with reference to the accompanying drawings.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, and it is obvious that the drawings in the following description are only some embodiments of the present invention, and for those skilled in the art, other drawings can be obtained according to these drawings without creative efforts.

Fig. 1 is a schematic structural diagram of a heat pump system according to a first embodiment of the present invention.

Fig. 2 is a schematic structural diagram of a heat pump system according to a second embodiment of the present invention.

Fig. 3 is a schematic view of a refrigerant flow path of the heat pump system shown in fig. 2 in the first cooling mode.

Fig. 4 is a schematic view of a refrigerant flow path of the heat pump system shown in fig. 2 in the second cooling mode.

Fig. 5 is a schematic diagram of a refrigerant flow path of the heat pump system shown in fig. 2 in the third cooling mode.

Fig. 6 is a schematic view of a refrigerant flow path of the heat pump system shown in fig. 2 in the first heating mode.

Fig. 7 is a schematic view of a refrigerant flow path of the heat pump system shown in fig. 2 in the second heating mode.

Fig. 8 is a schematic view of a refrigerant flow path of the heat pump system shown in fig. 2 in the third heating mode.

Fig. 9 is a schematic view of a refrigerant flow path of the heat pump system shown in fig. 2 in the first defrosting mode.

Fig. 10 is a schematic view of a refrigerant flow path of the heat pump system shown in fig. 2 in the second defrosting mode.

Fig. 11 is a schematic structural view of a heat pump system in a third embodiment of the present invention.

Fig. 12 is a schematic structural view of a heat pump system in a fourth embodiment of the present invention.

Fig. 13 is a schematic structural view of a heat pump system according to a fifth embodiment of the present invention.

Fig. 14 is a schematic structural view of a heat pump system in a sixth embodiment of the present invention.

Fig. 15 is a logic block diagram of a method of controlling a heat pump system in accordance with some embodiments of the present invention.

Fig. 16 is a schematic diagram of a control device according to some embodiments of the invention.

In the figure:

100. an indoor unit; 200. an outdoor unit; 300. a switching device;

1. a compressor; 11. an exhaust port; 12. an air suction port;

2. a first switching valve; 2D, a first valve port; 2C, a second valve port; 2E, a third valve port; 2S, a fourth valve port;

3. a second switching valve; 3D, a first switching port; 3C, a second switching port; 3E, a third switching port; 3S, a fourth switching port;

4. a first valve; 5. a second valve;

7. an indoor fan;

81. a first pipeline; 82. a second pipeline; 83. a third pipeline; 84. a fourth pipeline;

9. an indoor heat exchanger; 9a, a first port; 9b, a second port;

12. an inter-tube heat exchanger; 121. a first flow passage; 122. a second flow passage; q, a first working port; m, a second working port; p, a third working port; n, a fourth working port;

13. an indoor throttle; 14. a first shut-off valve; 15. a second stop valve;

20. a first outdoor heat exchanger; 20a, a first interface; 20b, a second interface;

21. a second outdoor heat exchanger; 21a, a first port; 21b, a second port;

22. a first outdoor orifice; 23. a second outdoor restriction;

24. a first outdoor fan; 25. a second outdoor fan;

26. a memory; 27. a processor; 28. a communication interface; 29. a bus;

F. and connecting points.

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. The following description of at least one exemplary embodiment is merely illustrative in nature and is in no way intended to limit the invention, its application, or uses. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without any inventive step, are within the scope of the present invention.

Techniques, methods, and apparatus known to those of ordinary skill in the relevant art may not be discussed in detail but are intended to be part of the specification where appropriate.

In the description of the present invention, it is to be understood that the orientation or positional relationship indicated by the orientation words such as "front, rear, upper, lower, left, right", "lateral, vertical, horizontal" and "top, bottom", etc. are usually based on the orientation or positional relationship shown in the drawings, and are only for convenience of description and simplicity of description, and in the case of not making a reverse description, these orientation words do not indicate and imply that the device or element being referred to must have a specific orientation or be constructed and operated in a specific orientation, and therefore, should not be considered as limiting the scope of the present invention; the terms "inner and outer" refer to the inner and outer relative to the profile of the respective component itself.

In the description of the present invention, it should be understood that the terms "first", "second", etc. are used to define the components, and are used only for the convenience of distinguishing the corresponding components, and if not otherwise stated, the terms have no special meaning, and thus, should not be construed as limiting the scope of the present invention.

In addition, the technical features involved in the different embodiments of the present invention described below may be combined with each other as long as they do not conflict with each other.

Fig. 1-14 schematically illustrate the construction of the heat pump system of the present invention. Fig. 15 exemplarily shows a control method of the present invention. Fig. 16 exemplarily shows a control device of the present invention.

Referring to fig. 1 to 14, the heat pump system according to the present invention includes a compressor 1, an indoor heat exchanger 9, a first outdoor heat exchanger 20, a second outdoor heat exchanger 21, and a switching device 300.

The compressor 1 compresses a refrigerant. The compressor 1 has a discharge port 11 and a suction port 12. The refrigerant compressed by the compressor 1 is discharged from the discharge port 11. The refrigerant after the cooling or heating cycle flows back to the compressor 1 through the suction port 12 and is compressed by the compressor 1. Referring to fig. 1-11 and 14, in some embodiments, the compressor 1 is located indoors, which reduces the risk of theft of the compressor 1. And as a modification, referring to fig. 12 and 13, in other embodiments, the compressor 1 may be disposed outdoors.

The indoor heat exchanger 9 is arranged indoors, belongs to a part of the indoor unit, and is used for realizing heat exchange between a refrigerant and indoor air so as to cool or heat the indoor air and realize the purposes of refrigeration or heating. The indoor heat exchanger 9 has a first port 9a and a second port 9b for allowing a refrigerant to enter and exit the indoor heat exchanger 9.

Referring to fig. 1 to 14, in some embodiments, an indoor fan 24 is correspondingly disposed at the indoor heat exchanger 9, and is configured to promote heat exchange between the refrigerant flowing through the indoor heat exchanger 9 and the indoor air, so as to improve a heat exchange effect of the refrigerant at the indoor heat exchanger 9. Meanwhile, an indoor throttling piece 13 is correspondingly arranged at the indoor heat exchanger 9. The indoor throttling element 13 is connected to the second port 9b, and is configured to throttle the refrigerant entering and exiting the indoor heat exchanger 9. The indoor throttle 13 may be an electronic expansion valve, a thermostatic expansion valve, a throttle orifice plate, or other throttle elements.

The first outdoor heat exchanger 20 and the second outdoor heat exchanger 21 are disposed outdoors, are part of an outdoor unit, and are used for exchanging heat between a refrigerant and outdoor air, and together with the indoor heat exchanger 9, complete a temperature adjustment process. The first outdoor heat exchanger 20 has a first connection port 20a and a second connection port 20b for allowing the refrigerant to enter and exit the first outdoor heat exchanger 20. The second outdoor heat exchanger 21 has a first port 21a and a second port 21b for allowing the refrigerant to enter and exit the second outdoor heat exchanger 21. The first outdoor heat exchanger 20 and the second outdoor heat exchanger 21 may be provided in the same outdoor unit, or may be provided in two separate outdoor units. The first and

second stop valves

14 and 15 may be installed on the pipes between the outdoor unit and the indoor unit to facilitate the assembly and disassembly of the pipes between the indoor and outdoor units.

Referring to fig. 1 to 14, in some embodiments, a first outdoor fan 24 is disposed at the first outdoor heat exchanger 20, and is configured to promote heat exchange between the refrigerant and outdoor air when the refrigerant flows through the first outdoor heat exchanger 20, so as to promote heat exchange effect of the refrigerant at the first outdoor heat exchanger 20. The second outdoor heat exchanger 21 is correspondingly provided with a second outdoor fan 25 for promoting heat exchange between the refrigerant flowing through the second outdoor heat exchanger 21 and outdoor air, so as to improve the heat exchange effect of the refrigerant at the second outdoor heat exchanger 21. The first outdoor fan 24 and the first outdoor heat exchanger 20 may be located in the first air duct, the second outdoor fan 25 and the second outdoor heat exchanger 21 are located in the second air duct, and the first air duct and the second air duct are independently disposed.

In addition, with continued reference to fig. 1-14, in some embodiments, the first outdoor heat exchanger 20 and the second outdoor heat exchanger 21 are further provided with a first outdoor throttling element 22 and a second outdoor throttling element 23, respectively. The first outdoor throttling element 22 and the second outdoor throttling element 23 are respectively connected with the second port 20b and the second port 21b, and are respectively used for throttling the refrigerants entering and exiting the first outdoor heat exchanger 20 and the second outdoor heat exchanger 21. The first outdoor throttle 22 and the second outdoor throttle 23 may be various throttle elements such as an electronic expansion valve, a thermostatic expansion valve, and a throttle orifice plate.

In order to improve the problem of the imbalance of the indoor temperature during defrosting and improve the temperature control accuracy of the heat pump system, referring to fig. 1 to 14, in some embodiments, the discharge port 11 and the suction port 12 of the compressor 1 are connected to the first port 9a of the indoor heat exchanger 9, the first port 20a of the first outdoor heat exchanger 20, and the first port 21a of the second outdoor heat exchanger 21 through the switching device 300.

The second port 9b of the indoor heat exchanger 9 and the second port 20b of the first outdoor heat exchanger 20 are connected by a first pipe 81. The second port 21b of the second outdoor heat exchanger 21 is connected to the first pipe 81 through a second pipe 82. The first pipe 81 and the second pipe 82 are connected at a connection point F. In this case, the aforementioned indoor orifice 13 and the first outdoor orifice 22 are both provided on the first pipe 81 and are respectively located between the second port 9b and the connection point F, and between the second port 20b and the connection point F; the second outdoor throttling element 23 is disposed on the second pipeline 82, i.e. between the second port 21b and the connection point F.

The switching device 300 controls the indoor heat exchanger 9, the first outdoor heat exchanger 20, and the second outdoor heat exchanger 21 to switch between the evaporator mode and the condenser mode by controlling the on-off relationship among the first port 9a of the indoor heat exchanger 9, the first port 20a of the first outdoor heat exchanger 20, and the first port 21a of the second outdoor heat exchanger 21, and the discharge port 11 and the suction port 12 of the compressor 1. The evaporator mode refers to a state in which the heat exchanger functions as an evaporator. The condenser mode refers to a state when the heat exchanger functions as a condenser.

Also, the switching device 300 is configured to be able to control one of the first interface 20a and the first port 21a and the first port 9a to be communicated with the discharge port 11 and the other of the first interface 20a and the first port 21a to be communicated with the suction port 12 when the heat pump system is in the defrosting mode, that is, to control one of the first outdoor heat exchanger 20 and the second outdoor heat exchanger 21 and the indoor heat exchanger 9 to be in the condenser mode and the other of the first outdoor heat exchanger 20 and the second outdoor heat exchanger 21 to be in the evaporator mode.

When defrosting is needed, the switching device 300 is controlled to operate, so that one of the first outdoor heat exchanger 20 and the second outdoor heat exchanger 21 and the indoor heat exchanger 9 are both in the condenser mode, and the other of the first outdoor heat exchanger 20 and the second outdoor heat exchanger 21 is in the evaporator mode, so that when defrosting is performed on one of the first outdoor heat exchanger 20 and the second outdoor heat exchanger 21 in the condenser mode, the one of the first outdoor heat exchanger 20 and the second outdoor heat exchanger 21 in the evaporator mode can provide heat required for defrosting, so that heat can be absorbed from the outdoor during defrosting, heat does not need to be absorbed from the indoor, the indoor heat exchanger 9 does not need to be switched to the evaporator mode again, and can be kept in the condenser mode, therefore, indoor temperature fluctuation caused by heating due to switching of the indoor heat exchanger 9 to the evaporator mode during defrosting can be avoided, the problem of indoor temperature imbalance in the defrosting process is solved, the temperature control accuracy of the heat pump system is effectively improved, the application of the heat pump system in occasions with higher requirements on the isothermal control accuracy of the constant temperature and humidity machine becomes possible, and the application range of the heat pump system is effectively expanded.

For example, referring to fig. 9, when the second outdoor heat exchanger 21 needs defrosting, the second outdoor heat exchanger 21 is switched to the condenser mode, and the first outdoor heat exchanger 20 is still kept in the evaporator mode, at this time, the first outdoor heat exchanger 20 in the evaporator mode can absorb outdoor heat for defrosting of the second outdoor heat exchanger 21 in the condenser mode, so that when the second outdoor heat exchanger 21 is defrosted, the indoor heat exchanger 9 does not need to be switched to the evaporator mode, but can keep the condenser mode, and continue heating, so that the defrosting purpose of the second outdoor heat exchanger 21 is achieved, and meanwhile, the output of heating capacity of the indoor heat exchanger 9 is not affected, and the stability of indoor temperature is improved. The defrosting process of the second outdoor heat exchanger 21 may be referred to as a first defrosting mode, in other words, the first defrosting mode refers to an operation mode of the heat pump system when the second outdoor heat exchanger 21 is defrosted.

For another example, referring to fig. 10, when the first outdoor heat exchanger 20 needs defrosting, the first outdoor heat exchanger 20 is switched to the condenser mode, and the second outdoor heat exchanger 21 is still kept in the evaporator mode, at this time, the second outdoor heat exchanger 21 in the evaporator mode can absorb outdoor heat for defrosting of the first outdoor heat exchanger 20 in the condenser mode, so that when the first outdoor heat exchanger 20 is defrosted, the indoor heat exchanger 9 can still be kept in the condenser mode to continue heating, thereby achieving the purpose of defrosting of the first outdoor heat exchanger 20, not affecting the output of heating capacity of the indoor heat exchanger 9, and improving the stability of indoor temperature. The defrosting process of the first outdoor heat exchanger 20 may be referred to as a second defrosting mode, in other words, the second defrosting mode refers to an operation mode of the heat pump system when the first outdoor heat exchanger 20 is defrosted.

It can be seen that, based on the aforementioned connection relationship and mutual cooperation among the switching device 300, the first outdoor heat exchanger 20, the second outdoor heat exchanger 21 and the indoor heat exchanger 9, an asynchronous defrosting process (i.e., the first outdoor heat exchanger 20 and the second outdoor heat exchanger 21 do not defrost at the same time) can be realized, so that the indoor heat exchanger 9 can be always kept in a condenser mode in a defrosting mode (including a first defrosting mode and a second defrosting mode), the heating capacity is continuously output, the problem of imbalance of indoor temperature in the defrosting process is effectively improved, and the temperature control accuracy of the heat pump system is improved.

In addition, during defrosting, the indoor heat exchanger 9 is always in the condenser mode, and the advantages are that:

(1) the problem of the imbalance of the indoor temperature of the primary heating section after defrosting is finished can be solved, and the temperature control accuracy is further improved. Traditional heat pump system, after indoor heat exchanger switches to the evaporimeter mode in the defrosting in-process, for preventing to blow cold wind, cause the indoor temperature to further reduce, indoor fan is forced the bring to rest, this causes indoor heat exchanger evaporation variation, the system returns the liquid seriously, liquid refrigerant exists in vapour and liquid separator in a large number, it is serious not enough to lead to the circulation refrigerant of heating after the defrosting, the heating capacity can not 100% resume after the defrosting, indoor temperature still is disorder after the defrosting, promptly, traditional heat pump system, not only there is the indoor temperature imbalance problem in the defrosting in-process, and resume the primary segment of heating after the defrosting finishes, also there is the indoor temperature imbalance problem. In the heat pump system provided by the invention, the indoor heat exchanger 9 can be always in the condenser mode in the defrosting process and continuously heats, so that the indoor fan 7 can continuously run without stopping, the problem of insufficient refrigerant in the primary heating section after defrosting due to stopping of the indoor fan 7 can be avoided, and the problem of imbalance of indoor temperature in the primary heating section after defrosting is effectively solved.

(2) Is beneficial to reducing energy consumption. On one hand, the temperature control accuracy of the heat pump system is improved, the application range can be expanded to occasions with higher temperature control accuracy requirements, and the application of an electric heating system in the occasions is reduced, so that the power consumption can be reduced, and the energy consumption is reduced. On the other hand, in the defrosting process, the indoor heat exchanger 9 can be always kept in the condenser mode, so that the problem of indoor temperature imbalance is solved, and therefore, an electric heating system is not needed to be used for heating in the defrosting process to assist in adjusting the indoor temperature.

Therefore, the heat pump system provided by the invention is an energy-saving heat pump system capable of accurately controlling the temperature.

Besides the asynchronous defrosting process, the heat pump system provided by the invention can realize normal refrigerating and heating processes.

Wherein, in order to implement a normal cooling process, referring to fig. 3-5, in some embodiments, the switching device 300 is further configured to: when the heat pump system is in the cooling mode, the indoor heat exchanger 9 is controlled to be in the evaporator mode and the first and second

outdoor heat exchangers

20 and 21 are in the condenser mode, or one of the first and second

outdoor heat exchangers

20 and 21 is in the evaporator mode and the other is in the condenser mode. In this way, when cooling is required, the switching device 300 is controlled to operate so that the indoor heat exchanger 9 is in the evaporator mode and the first and second

outdoor heat exchangers

20 and 21 are in the condenser mode, or one of the first and second

outdoor heat exchangers

20 and 21 and the indoor heat exchanger 9 are in the evaporator mode and the other of the first and second

outdoor heat exchangers

20 and 21 is in the condenser mode, so that the cooling mode can be realized. The cooling mode in which the indoor heat exchanger 9 is in the evaporator mode and the first and second

outdoor heat exchangers

20 and 21 are in the condenser mode may be referred to as a first cooling mode. The cooling mode when the indoor heat exchanger 9 and the first outdoor heat exchanger 20 are both in the evaporator mode and the second outdoor heat exchanger 21 is in the condenser mode may be referred to as a second cooling mode. The cooling mode when the indoor heat exchanger 9 and the second outdoor heat exchanger 21 are both in the evaporator mode and the first outdoor heat exchanger 20 is in the condenser mode may be referred to as a first cooling mode. In some embodiments, the cooling modes include a first cooling mode, a second cooling mode, and a third cooling mode. In the cooling process, as the outdoor temperature decreases, the heat pump system sequentially operates in the first cooling mode and the second cooling mode (or the third cooling mode).

Whereas, to implement a normal heating process, referring to fig. 6-8, in some embodiments, the switching device 300 is configured to: when the heat pump system is in the heating mode, the indoor heat exchanger 9 is controlled to be in the condenser mode and the first and second

outdoor heat exchangers

20 and 21 are in the evaporator mode, or one of the first and second

outdoor heat exchangers

20 and 21 is in the evaporator mode and the other is in the condenser mode. In this way, when heating is required, the heating mode can be realized by controlling the switching device 300 to operate so that the indoor heat exchanger 9 is in the condenser mode and the first and second

outdoor heat exchangers

20 and 21 are in the evaporator mode, or so that one of the first and second

outdoor heat exchangers

20 and 21 and the indoor heat exchanger 9 are in the condenser mode and the other of the first and second

outdoor heat exchangers

20 and 21 is in the evaporator mode. The heating mode in which the indoor heat exchanger 9 is in the condenser mode and the first and second

outdoor heat exchangers

20 and 21 are in the evaporator mode may be referred to as a first heating mode. The heating mode when the indoor heat exchanger 9 and the first outdoor heat exchanger 20 are both in the condenser mode and the second outdoor heat exchanger 21 is in the evaporator mode may be referred to as a second heating mode. The heating mode when the indoor heat exchanger 9 and the second outdoor heat exchanger 21 are both in the condenser mode and the first outdoor heat exchanger 20 is in the evaporator mode may be referred to as a third heating mode. In some embodiments, the heating mode includes a first heating mode, a second heating mode, and a third heating mode. In the heating process, as the outdoor temperature decreases, the heat pump system sequentially operates in the second heating mode (or the third heating mode), the first heating mode, and the defrosting mode. When defrosting is needed, the heat pump system is switched from the first heating mode to the defrosting mode. In the whole heating process, the indoor heat exchanger 9 is always in the condenser mode.

The heat pump system is set to realize a refrigeration mode and a heating mode and also realize a first defrosting mode and a second defrosting mode, so that the operation mode is more various and the functions are richer.

As an implementation of the switching device 300 in the previous embodiments, referring to fig. 2-14, in some embodiments, the switching device 300 includes a first switching valve 2 and a second switching valve 3.

The first switching valve 2 includes a first port 2D, a second port 2C, a third port 2E, and a fourth port 2S. The first valve port 2D communicates with the exhaust port 11. The second port 2C communicates with the first port 21 a. The third port 2E is connected to the first port 9a through a third line 83. The fourth port 2S communicates with the suction port 12. When the first port 2D communicates with one of the second port 2C and the third port 2E, the fourth port 2S communicates with the other of the second port 2C and the third port 2E, in other words, the first switching valve 2 has a first state in which the first port 2D communicates with the second port 2C and the fourth port 2S communicates with the third port 2E, and a second state in which the first port 2D communicates with the third port 2E and the fourth port 2S communicates with the second port 2C. Thus, the first switching valve 2 is switched between the first state and the second state, and the on-off relationship between the first port 21a and the first port 9a, and the exhaust port 11 and the suction port 12, and thus the second outdoor heat exchanger 21 and the indoor heat exchanger 9, are controlled to be switched between the evaporator mode and the condenser mode.

In some embodiments, referring to fig. 2-10, the first switching valve 2 is a four-way valve, and in this case, the first switching valve 2 may also be referred to as a first four-way valve. When the first switching valve 2 adopts a four-way valve structure, the structure is simpler, and the control is more convenient. The implementation of the first switching valve 2 is not limited to this, for example, in other embodiments, the first switching valve 2 may also include several valves (e.g. solenoid valves) connected in series and/or in parallel, and the valves cooperate to implement the function of the first switching valve 2.

In addition, the switching of the first switching valve 2 between the first state and the second state may be controlled by controlling whether the first switching valve 2 is energized or not. For example, in some embodiments, the first switching valve 2 is in the first state when it is powered down; the first switching valve 2 is in the second state when energized.

The second switching valve 3 includes a first switching port 3D, a second switching port 3C, a third switching port 3E, and a fourth switching port 3S. The first switching port 3D communicates with the exhaust port 11. The second switching port 3C communicates with the first port 20 a. The third switching port 3E is connected to the first port 9a through a fourth line 84. The fourth switching port 3S communicates with the intake port 12. When the first switching port 3D communicates with one of the second switching port 3C and the third switching port 3E, the fourth switching port 3S communicates with the other of the second switching port 3C and the third switching port 3E, in other words, the second switching valve 3 has a first operating state in which the first switching port 3D communicates with the second switching port 3C and the fourth switching port 3S communicates with the third switching port 3E and a second operating state in which the first switching port 3D communicates with the third switching port 3E and the fourth switching port 3S communicates with the second switching port 3C. In this way, the second switching valve 3 is switched between the first operating state and the second operating state, and the on-off relationship between the first port 20a and the first port 9a, and the exhaust port 11 and the suction port 12, and thus the first outdoor heat exchanger 20 and the indoor heat exchanger 9, are controlled to be switched between the evaporator mode and the condenser mode.

In some embodiments, referring to fig. 2-14, the second switching valve 3 is a four-way valve, and in this case, the second switching valve 3 may also be referred to as a second four-way valve. When the second switching valve 3 adopts a four-way valve structure, the structure is simpler, and the control is more convenient. However, the implementation manner of the second switching valve 3 is not limited to this, for example, in other embodiments, the second switching valve 3 may also include several valves (e.g. solenoid valves) connected in series and/or in parallel, and these valves are a combination of these valves, and cooperate with each other to implement the function of the second switching valve 3.

In addition, the switching of the second switching valve 3 between the first operating state and the second operating state may be controlled by controlling whether the second switching valve 3 is energized or not. For example, in some embodiments, when the second switching valve 3 is powered off, it is in the first working state; when the second switching valve 3 is powered on, the second switching valve is in a second working state.

Based on the first and

second switching valves

2 and 3 being provided, it is possible to easily and efficiently control the communication relationship between the first port 9a, the first port 20a, and the first port 21a, and the discharge port 11 and the suction port 12, so as to control the indoor heat exchanger 9, the first outdoor heat exchanger 20, and the second outdoor heat exchanger 21 to switch between the evaporator mode and the condenser mode.

Referring to fig. 3, when the heat pump system is in the first cooling mode, the first switching valve 2 is in the first state, the second switching valve 3 is in the first operating state, and the switching device 300 controls the first port 20a and the first port 21a to communicate with the exhaust port 11, and the first port 9a to communicate with the suction port 12, so that the first outdoor heat exchanger 20 and the second outdoor heat exchanger 21 are both in the condenser mode, and the indoor heat exchanger 9 is in the evaporator mode.

Referring to fig. 4, when the heat pump system is in the second cooling mode, the first switching valve 2 is in the first state, the second switching valve 3 is in the second operating state, the switching device 300 controls the first port 21a to communicate with the exhaust port 11, and the first port 9a and the first port 20a both communicate with the suction port 12, so that the second outdoor heat exchanger 21 is in the condenser mode, and the indoor heat exchanger 9 and the first outdoor heat exchanger 20 are both in the evaporator mode.

Referring to fig. 5, when the heat pump system is in the third cooling mode, the first switching valve 2 is in the second state, the third switching valve 3 is in the first operating state, the switching device 300 controls the first port 21a to communicate with the exhaust port 11, and both the first port 9a and the first port 21a communicate with the suction port 12, so that the first outdoor heat exchanger 20 is in the condenser mode, and both the indoor heat exchanger 9 and the second outdoor heat exchanger 21 are in the evaporator mode.

Referring to fig. 6, when the heat pump system is in the first heating mode, the first switching valve 2 is in the second state, the second switching valve 3 is in the first operating state, and the switching device 300 controls the first port 9a to communicate with the exhaust port 11, and the first port 20a and the first port 21a to communicate with the suction port 12, so that the indoor heat exchanger 9 is in the condenser mode, and the first outdoor heat exchanger 20 and the second outdoor heat exchanger 21 are both in the evaporator mode.

Referring to fig. 7, when the heat pump system is in the second heating mode, the first switching valve 2 is in the second state, the third switching valve 3 is in the first operating state, the switching device 300 controls the first port 9a and the first port 20a to both communicate with the exhaust port 11, and the first port 21a to communicate with the suction port 12, so that the second outdoor heat exchanger 21 is in the evaporator mode, and both the indoor heat exchanger 9 and the first outdoor heat exchanger 20 are in the condenser mode.

Referring to fig. 8, when the heat pump system is in the third heating mode, the first switching valve 2 is in the first state, the second switching valve 3 is in the second operating state, the switching device 300 controls the first port 9a and the first port 21a to both communicate with the exhaust port 11, and the first port 21a to communicate with the suction port 12, so that the first outdoor heat exchanger 20 is in the evaporator mode, and both the indoor heat exchanger 9 and the second outdoor heat exchanger 21 are in the condenser mode.

Referring to fig. 9, when the heat pump system is in the first defrosting mode, the first switching valve 2 is in the first state, the second switching valve 3 is in the second operating state, the first port 9a and the first port 21a are both controlled to communicate with the exhaust port 11, the first port 20a communicates with the suction port 12, so that the indoor heat exchanger 9 and the second outdoor heat exchanger 21 are both in the condenser mode, and the first outdoor heat exchanger 20 is in the evaporator mode.

Referring to fig. 10, when the heat pump system is in the second frost removal mode, the first switching valve 2 is in the second state, the second switching valve 3 is in the first operating state, the first port 9a and the first port 20a are both controlled to communicate with the exhaust port 11, the first port 21a communicates with the suction port 12, so that the indoor heat exchanger 9 and the first outdoor heat exchanger 20 are both in the condenser mode, and the second outdoor heat exchanger 21 is in the evaporator mode.

With continued reference to fig. 9 and 10, in order to prevent the third pipeline 83 and the fourth pipeline 84 from being communicated when the first switching valve 2 and the second switching valve 3 are in the opposite state, so that the high-low pressure direct communication is caused, and the realization of the system function and the system working safety are affected, in some embodiments, the third valve port 2E and the first port 9a, and the third switching port 3E and the first port 9a are connected in an on-off manner, so that when the first switching valve 2 and the second switching valve 3 are in the opposite state, the problem caused by the high-low pressure direct communication is avoided by controlling one of the third pipeline 83 and the fourth pipeline 84 to be communicated and the other to be disconnected.

For example, referring to fig. 9, in the first defrosting mode, the third valve port 2E and the first port 9a are in a disconnected state, and the third switching port 3E and the first port 9a are in a connected state, so that the high-pressure refrigerant flowing out of the exhaust port 11 and flowing through the fourth pipe 84 is prevented from directly flowing back to the suction port 12 through the third pipe 83, and high-pressure and low-pressure direct connection is caused.

For another example, referring to fig. 10, in the second frost removal mode, the third valve port 2E is in a communication state with the first port 9a, and the third switching port 3E is in a disconnection state with the first port 9a, so as to prevent the high-pressure refrigerant flowing out of the exhaust port 11 and flowing through the third pipeline 83 from directly flowing back to the suction port 12 through the fourth pipeline 84, and thus high-pressure and low-pressure refrigerant are directly conducted.

In order to realize the on-off connection between the third valve port 2E and the first port 9a and between the third switching port 3E and the first port 9a, referring to fig. 2 to 14, in some embodiments, the switching device 300 includes not only the first switching valve 2 and the second switching valve 3, but also the first valve 4 and the second valve 5. The first valve 4 is provided on the third line 83 and is configured to control the opening/closing of the third line 83, so as to achieve the openable/closable connection between the third valve port 2E and the first port 9 a. The second valve 5 is provided on the fourth pipe 84 and is configured to control on/off of the fourth pipe 84 to enable on/off connection between the third switching port 3E and the first port 9 a.

The first valve 4 and the second valve 5 may be solenoid valves or electric ball valves, and at this time, the on/off of the third pipeline 83 (i.e., between the third port 2E and the first port 9a) and the fourth pipeline 84 (i.e., between the third switching port 3E and the first port 9a) can be conveniently and efficiently controlled by controlling whether the first valve 4 and the second valve 5 are powered. For example, in some embodiments, when the first valve 4 and the second valve 5 are energized, the third line 83 and the fourth line 84 are controlled to communicate, respectively; when the first valve 4 and the second valve 5 lose power, the third pipeline 83 and the fourth pipeline 84 are controlled to be disconnected respectively.

When the switching device 300 includes the first switching valve 2, the second switching valve 3, the first valve 4, and the second valve 5, the operation of the switching device 300 includes controlling the first switching valve 2, the second switching valve 3, the first valve 4, and the second valve 5. For example, in some embodiments, the correspondence between the states of the components such as the first switching valve 2, the second switching valve 3, the first valve 4, and the second valve 5 and the operation modes of the heat pump system is shown in the attached table 1 below.

TABLE 1 corresponding relationship table between each part state and each operation mode of heat pump system

In some embodiments, adjustment strategies for the various components are set for different operating modes. And when the heat pump system operates in different operation modes, performing corresponding adjustment treatment on each part according to the adjustment strategy. For example, referring to the adjustment manners in parentheses in table 1 above, in some embodiments, in the first cooling/dehumidifying mode, the first heating mode, the first defrosting mode, and the second defrosting mode, the output of the compressor 1 is adjusted, the number of revolutions (the number of revolutions is the number of revolutions per unit time) of the indoor fan 7 is adjusted, and the opening of the indoor throttle 13, the first outdoor throttle 22, and the second outdoor throttle 23 is adjusted; performing rotation number adjustment of the first and second

outdoor fans

24 and 25 in the first cooling/dehumidifying mode and the first heating mode; in the first defrosting mode, the second outdoor fan 25 is turned off, and the number of revolutions of the first outdoor fan 24 is adjusted; in the second frost removal mode, the first outdoor fan 24 is turned off, and the number of revolutions of the second outdoor fan 25 is adjusted.

Fig. 3 to 10 respectively show refrigerant flow paths of the heat pump system in a first cooling mode, a second cooling mode, a third cooling mode, a first heating mode, a second heating mode, a third heating mode, a first defrosting mode and a second defrosting mode based on the cooperation of the first switching valve 2, the second switching valve 3, the first valve 4 and the second valve 5.

Referring to fig. 3, when the target operation mode is the first cooling mode, the first valve port 2D of the first switching valve 2 is controlled to be communicated with the second valve port 2C, the third valve port 2E is controlled to be communicated with the fourth valve port 2S, the first switching port 3D of the second switching valve 3 is controlled to be communicated with the second switching port 3C, the third switching port 3E is controlled to be communicated with the fourth switching port 3S, and the first valve 4 and the second valve 5 are controlled to be opened, so that the indoor heat exchanger 9 is in the evaporator mode, and the first outdoor heat exchanger 20 and the second outdoor heat exchanger 21 are in the condenser mode. At this time, the refrigerant flowing out of the compressor 1 is divided into two paths, one path flows to the first outdoor heat exchanger 20 through the first switching port 3D and the second switching port 3C of the second switching valve 3, condenses and releases heat at the first outdoor heat exchanger 20, the other path flows to the second outdoor heat exchanger 21 through the first valve port 2D and the second valve port 2C of the first switching valve 2, condenses and releases heat at the second outdoor heat exchanger 21, the two paths of refrigerant flowing out of the first outdoor heat exchanger 20 and the second outdoor heat exchanger 21 are merged at the connection point F and flow together to the indoor heat exchanger 9, evaporates and absorbs heat at the indoor heat exchanger 9 to cool the indoor air, then flows out of the indoor heat exchanger 9 and is divided into two paths, one path flows through the first valve 4 and the third valve port 2E and the fourth valve port 2S of the first switching valve 2, the other path flows through the second valve 5 and the third switching port 3E and the fourth switching port 3S of the second switching valve 3, finally, the refrigerant flows to the suction port 12 and returns to the compressor 1, thereby completing the whole refrigeration cycle.

Referring to fig. 4, when the target operation mode is the second cooling mode, the first port 2D of the first switching valve 2 is controlled to communicate with the second port 2C, the third port 2 is controlled to communicate with the fourth port 2S, and the first switching port 3D of the second switching valve 3 is controlled to communicate with the third switching port 3E, the second switching port 3C is controlled to communicate with the fourth switching port 3S, and the first valve 4 is controlled to be opened, and the second valve 5 is controlled to be closed, so that the indoor heat exchanger 9 and the first outdoor heat exchanger 20 are in the evaporator mode, and the second outdoor heat exchanger 21 is in the condenser mode. At this time, the refrigerant flowing out of the compressor 1 flows to the first outdoor heat exchanger 21 through the first valve port 2D and the second valve port 2C of the first switching valve 2, is condensed by the second outdoor heat exchanger 21 to release heat, flows out of the second outdoor heat exchanger 21, and is divided into two paths at the connection point F, one path flows through the indoor heat exchanger 9 to evaporate and absorb heat, and flows back to the compressor 1 through the first valve 4 and the third valve port 2E and the fourth valve port 2S of the first switching valve 2, and the other path flows through the first outdoor heat exchanger 20 to evaporate and absorb heat, and flows back to the compressor 1 through the third switching port 3C and the fourth switching port 3S of the second switching valve 3. In this process, the indoor heat exchanger 9 bears the evaporation load together with the first outdoor heat exchanger 20.

Referring to fig. 5, when the target operation mode is the third cooling mode, the first port 2D of the first switching valve 2 is controlled to communicate with the third port 2E, the second port 2C of the first switching valve 2 is controlled to communicate with the fourth port 2S, the first switching port 3D of the second switching valve 3 is controlled to communicate with the second switching port 3C, the third switching port 3E of the second switching valve 3 is controlled to communicate with the fourth switching port 3S, the first valve 4 is controlled to be closed, the second valve 5 is controlled to be opened, the indoor heat exchanger 9 and the second outdoor heat exchanger 21 are in the evaporator mode, and the first outdoor heat exchanger 20 is controlled to be in the condenser mode. At this time, the refrigerant flowing out of the compressor 1 flows to the first outdoor heat exchanger 20 through the first switching port 3D and the second switching port 3C of the second switching valve 3, is condensed by the first outdoor heat exchanger 20 to release heat, flows out of the first outdoor heat exchanger 20, and is divided into two paths at the connection point F, one path flows through the indoor heat exchanger 9 to evaporate and absorb heat, and flows back to the compressor 1 through the second valve 5 and the third switching port 3E and the fourth switching port 3S of the second switching valve 3, and the other path flows through the second outdoor heat exchanger 21 to evaporate and absorb heat, and flows back to the compressor 1 through the second valve port 2C and the fourth valve port 2S of the first switching valve 2. In this process, the indoor heat exchanger 9 bears the evaporation load together with the second outdoor heat exchanger 21.

Referring to fig. 6, when the target operation mode is the heating mode, the first port 2D of the first switching valve 2 is controlled to communicate with the third port 2E, the second port 2C of the first switching valve 2 is controlled to communicate with the fourth port 2S, the first switching port 3D of the second switching valve 3 is controlled to communicate with the third switching port 3E, the second switching port 3C of the second switching valve 3 is controlled to communicate with the fourth switching port 3S, and both the first valve 4 and the second valve 5 are controlled to be opened, so that the indoor heat exchanger 9 is in the condenser mode, and the first outdoor heat exchanger 20 and the second outdoor heat exchanger 21 are in the evaporator mode. At this time, the refrigerant flowing out of the compressor 1 is divided into two paths, one path flows to the first valve 4 through the first valve port 2D and the third valve port 2E of the first switching valve 2, the other path flows to the second valve 5 through the first switching port 3D and the third switching port 3E of the second switching valve 3, and the two paths of refrigerant flowing out of the first valve 4 and the second valve 5 are merged and flow to the indoor heat exchanger 9, where heat is condensed and released at the indoor heat exchanger 9 to heat the indoor air, and then flow out of the indoor heat exchanger 9 and are divided into two paths at the connection point F, and flow to the first outdoor heat exchanger 20 and the second outdoor heat exchanger 21, and after evaporation and heat absorption at the first outdoor heat exchanger 20 and the second outdoor heat exchanger 21, flow to the second valve port switching port 3C and the fourth switching port 3S of the second switching valve 3, and the second valve port 2C and the fourth valve port 2S of the first switching valve 2, finally, the refrigerant flows to the air suction port 12 and flows back to the compressor 1 after being merged, and the whole heating cycle is completed.

Referring to fig. 7, when the target operation mode is the second heating mode, the first port 2D of the first switching valve 2 is controlled to communicate with the third port 2E, the second port 2C is controlled to communicate with the fourth port 2S, the first switching port 3D of the second switching valve 3 is controlled to communicate with the second switching port 3C, the third switching port 3E is controlled to communicate with the fourth switching port 3S, the first valve 4 is controlled to be opened, the second valve 5 is controlled to be closed, the indoor heat exchanger 9 and the first outdoor heat exchanger 20 are both in the condenser mode, and the second outdoor heat exchanger 21 is controlled to be in the evaporator mode. At this time, the refrigerant flowing out of the compressor 1 is divided into two paths, one path flows to the indoor heat exchanger 9 through the first valve port 2D and the third valve port 2E of the first switching valve 2 and the first valve 4, is condensed and released heat at the indoor heat exchanger 9, and outputs heating amount, the other path flows to the first outdoor heat exchanger 20 through the first switching port 3D and the second switching port 3C of the second switching valve 3, is condensed and released heat at the first outdoor heat exchanger 20, and then the two paths of refrigerant flowing out of the indoor heat exchanger 9 and the first outdoor heat exchanger 20 join at the connection point F, flow to the second outdoor heat exchanger 21 together, and after being evaporated and absorbed heat by the second outdoor heat exchanger 21, flow to the suction port 12 through the second valve port 2C and the fourth valve port 2S of the first switching valve 2, and flow back to the compressor 1. In this process, the indoor heat exchanger 9 bears the condensation load together with the first outdoor heat exchanger 20.

Referring to fig. 8, when the target operation mode is the third heating mode, the first port 2D of the first switching valve 2 is controlled to communicate with the second port 2C, the third port 2E is controlled to communicate with the fourth port 2S, the first switching port 3D of the second switching valve 3 is controlled to communicate with the third switching port 3E, the second switching port 3C is controlled to communicate with the fourth switching port 3S, the first valve 4 is controlled to be closed, the second valve 5 is controlled to be opened, the indoor heat exchanger 9 and the second outdoor heat exchanger 21 are both in the condenser mode, and the first outdoor heat exchanger 20 is controlled to be in the evaporator mode. At this time, one path flows to the indoor heat exchanger 9 through the first switching port 3D and the third switching port 3E of the second switching valve 3 and the second valve 5, is condensed and released heat at the indoor heat exchanger 9, and outputs a heating amount, and the other path flows to the second outdoor heat exchanger 21 through the first valve port 2D and the second valve port 2C of the first switching valve 2, is condensed and released heat at the second outdoor heat exchanger 21, and then, the two paths of refrigerants flowing out from the indoor heat exchanger 9 and the second outdoor heat exchanger 21 join at the connection point F, flow to the first outdoor heat exchanger 20 together, evaporate and absorb heat through the first outdoor heat exchanger 20, flow to the suction port 12 through the second switching port 3C and the fourth switching port 3S of the second switching valve 3, and flow back to the compressor 1. In this process, the indoor heat exchanger 9 bears the condensation load together with the second outdoor heat exchanger 21.

Referring to fig. 9, when the target operation mode is the first defrosting mode, the first valve port 2D of the first switching valve 2 is controlled to communicate with the second valve port 2C, the third valve port 2E is controlled to communicate with the fourth valve port 2S, the first switching port 3D of the second switching valve 3 is controlled to communicate with the third switching port 3E, the second switching port 3C is controlled to communicate with the fourth switching port 3S, the first valve 4 is controlled to be closed, the second valve 5 is controlled to be opened, the second outdoor heat exchanger 21 and the indoor heat exchanger 9 are both in the condenser mode, and the first outdoor heat exchanger 20 is in the evaporator mode. At this time, the refrigerant flowing out of the compressor 1 is divided into two paths, one path flows to the indoor heat exchanger 9 through the first switching port 3D and the third switching port 3E of the second switching valve 3 and the second valve 5, is condensed and released heat at the indoor heat exchanger 9, and outputs heating amount, the other path flows to the second outdoor heat exchanger 21 through the first valve port 2D and the second valve port 2C of the first switching valve 2, is condensed and released heat at the second outdoor heat exchanger 21, is defrosted, and then the two paths of refrigerants flowing out of the indoor heat exchanger 9 and the second outdoor heat exchanger 21 join at the connection point F, flow to the first outdoor heat exchanger 20 together, evaporate and absorb heat through the first outdoor heat exchanger 20, flow to the suction port 12 through the second switching port 3C and the fourth switching port 3S of the second switching valve 3, and flow back to the compressor 1.

Referring to fig. 10, when the target operation mode is the second defrosting mode, the first port 2D of the first switching valve 2 is controlled to communicate with the third port 2E, the second port 2C of the first switching valve 2 is controlled to communicate with the fourth port 2S, the first switching port 3D of the second switching valve 3 is controlled to communicate with the second switching port 3C, the third switching port 3E of the second switching valve 3 is controlled to communicate with the fourth switching port 3S, the first valve 4 is controlled to be opened, the second valve 5 is controlled to be closed, the first outdoor heat exchanger 20 and the indoor heat exchanger 9 are both in the condenser mode, and the second outdoor heat exchanger 21 is controlled to be in the evaporator mode. At this time, the refrigerant flowing out of the compressor 1 is divided into two paths, one path flows to the indoor heat exchanger 9 through the first valve port 2D and the third valve port 2E of the first switching valve 2 and the first valve 4, is condensed and released heat at the indoor heat exchanger 9, and outputs heating amount, the other path flows to the first outdoor heat exchanger 20 through the first switching port 3D and the second switching port 3C of the second switching valve 3, is condensed and released heat at the first outdoor heat exchanger 20, is defrosted, and then the two paths of the refrigerant flowing out of the indoor heat exchanger 9 and the first outdoor heat exchanger 20 join at the connection point F, flow to the second outdoor heat exchanger 21 together, evaporate and absorb heat through the second outdoor heat exchanger 21, flow to the suction port 12 through the second valve port 2C and the fourth valve port 2S of the first switching valve 2, and flow back to the compressor 1.

It can be seen that the first switching valve 2, the second switching valve 3, the first valve 4 and the second valve 5 are matched, so that the working modes of the indoor heat exchanger 9, the first outdoor heat exchanger 20 and the second outdoor heat exchanger 21 can be conveniently switched, the requirements of the refrigeration, heating and defrosting processes are met, the asynchronous defrosting process is realized, the indoor heat exchanger 9 can be kept in the condenser mode in the defrosting process, the heating temperature control imbalance problem caused by the fact that the indoor heat exchanger 9 is switched to the evaporator mode in the defrosting process is reduced, and the more accurate and energy-saving temperature adjusting process is realized.

To further reduce the negative impact of the defrosting process on the heat pump system, and referring to fig. 1-14, in some embodiments, the heat pump system further includes an inter-tube heat exchanger 12 located indoors or outdoors. The inter-tube heat exchanger 12 is provided with a first flow path 121 and a second flow path 122 that can exchange heat with each other. Also, referring to fig. 1-8, in some embodiments, the first port 20a and the first port 21a are connected to the switching device 300 through a first flow passage 121 and a second flow passage 122, respectively. Alternatively, referring to fig. 9 to 10, in other embodiments, the second port 20b and the second port 21b are connected to the indoor heat exchanger 9 through the first flow passage 121 and the second flow passage 122, respectively. Here, an interface of the first flow path 121 to the switching device 300 or the indoor heat exchanger 9 may be referred to as a first working port q, an interface of the first flow path 121 to the first outdoor heat exchanger 20 may be referred to as a second working port m, an interface of the second flow path 122 to the switching device 300 or the indoor heat exchanger 9 may be referred to as a third working port p, and an interface of the first flow path 121 to the second outdoor heat exchanger 21 may be referred to as a fourth working port n.

For example, referring to fig. 1 to 10 and 12, in some embodiments, the inter-tube heat exchanger 12 is disposed outdoors and connected between the first and second

outdoor heat exchangers

20 and 21 and the switching device 300. At this time, the first port 20a and the first port 21a are connected to the switching device 300 through the first flow passage 121 and the second flow passage 122, respectively. The first working port q is connected to the switching device 300, specifically, to the second switching port 3C of the second switching valve 3. The second work port m is connected to the first port 20 a. The third working port p is connected to the switching device 300, in particular to the second port 2C of the first switching valve 2. The fourth port n is connected to the first port 21 a. Of these, the embodiment of fig. 1-6 differs from the embodiment of fig. 8 mainly in that in the embodiment of fig. 1-6 the compressor 1 is located indoors, whereas in the embodiment of fig. 8 the compressor 1 is located outdoors.

For another example, referring to fig. 11, in some embodiments, the inter-tube heat exchanger 12 is still connected between the first and second

outdoor heat exchangers

20 and 21 and the switching device 300, and the connection relationship is the same as that of the embodiments shown in fig. 1 to 6 and 8, but the inter-tube heat exchanger 12 is not disposed outdoors, but disposed indoors. Also, as shown in fig. 11, in this embodiment, the compressor 1 is also located indoors.

For another example, referring to fig. 13 and 14, in some embodiments, the inter-tube heat exchanger 12 is still disposed outdoors, but is not connected between the first and second

outdoor heat exchangers

20 and 21 and the switching device 300, but is connected between the first and second

outdoor heat exchangers

20 and 21 and the indoor heat exchanger 9. At this time, the second port 20b and the second port 21b are connected to the indoor heat exchanger 9 through the first flow passage 121 and the second flow passage 122, respectively. Specifically, the first flow path 121 is located between the first outdoor throttle 22 and the second port 20b of the heat pump system. The second flow passage 122 is located between the second outdoor throttle 23 and the second port 21b of the heat pump system. The first working port q is connected to the second port 9b of the indoor heat exchanger 9 through the first outdoor throttle 22. The second work port m is connected to the second port 20 b. The third working port p is connected to the connection point F through the third orifice 23, thereby achieving connection with the second port 9b of the indoor heat exchanger 9. The fourth port n is connected to the second port 21 b. The embodiment shown in fig. 13 and 14 differs therefrom mainly in that in the embodiment shown in fig. 13, the compressor 1 is located outdoors, whereas in the embodiment shown in fig. 14, the compressor 1 is located indoors.

Based on the above arrangement, referring to fig. 9 and 10, in the defrosting mode, the inter-tube heat exchanger 12 can evaporate the refrigerant together with the outdoor heat exchanger serving as the evaporator before the refrigerant flows back to the compressor 1, and on the basis of the outdoor heat exchanger serving as the evaporator, evaporation of the refrigerant flowing back to the compressor 1 is increased, so that defrosting return is reduced or even avoided, which has an important role in rapidly recovering the output of heating capacity after defrosting, and can effectively reduce the negative influence of defrosting on the heat pump system, and improve the temperature control accuracy and the operation safety of the heat pump system.

For example, in an embodiment in which the inter-tube heat exchanger 12 is disposed between the first and second outdoor heat exchangers 20 and 21 and the switching device 300, and the first port 20a and the first port 21a are connected to the switching device 300 through the first flow passage 121 and the second flow passage 122, respectively, referring to fig. 5, when the heat pump system is in the first defrosting mode, the low-temperature and low-pressure refrigerant flowing out of the first outdoor heat exchanger 20 flows through the first flow passage 121, due to the heat exchange temperature difference with the high-temperature and high-pressure refrigerant flowing out of the discharge port 12 and flowing through the second flow passage 122, therefore, the refrigerant in the second flow channel 122 can be absorbed and further evaporated, so that after the refrigerant is evaporated by the first outdoor heat exchanger 20 in the inter-tube heat exchanger 12, evaporating the refrigerant again, and evaporating most or all of the refrigerant flowing back to the compressor 1, so as to avoid or reduce defrosting liquid return and improve the temperature control accuracy and the operation safety of the heat pump system; meanwhile, referring to fig. 10, when the heat pump system is in the second defrosting mode, when the low-temperature and low-pressure refrigerant flowing out of the second outdoor heat exchanger 21 flows through the second flow channel 122, due to a heat exchange temperature difference between the low-temperature and low-pressure refrigerant flowing out of the exhaust port 12 and flowing through the first flow channel 121, the low-temperature and low-pressure refrigerant can exchange heat with the refrigerant in the first flow channel 121, absorb heat of the refrigerant in the first flow channel 121, and further evaporate, so that the inter-tube heat exchanger 12 can evaporate the refrigerant again after the refrigerant is evaporated by the second outdoor heat exchanger 21, most or all of the refrigerant flowing back to the compressor 1 is evaporated, thereby avoiding or reducing defrosting return liquid, and improving temperature control accuracy and operation safety of the heat pump system.

Similarly, in the embodiment where the inter-tube heat exchanger 12 is disposed between the first and second outdoor heat exchangers 20 and 21 and the indoor heat exchanger 9, and the first port 20a and the first port 21a are connected to the indoor heat exchanger 9 through the first flow passage 121 and the second flow passage 122, respectively, the inter-tube heat exchanger 12 can also improve the defrosting return phenomenon, and the operation process thereof is similar to the above description of fig. 5 to 6, and the difference is mainly that, in the defrosting mode, the refrigerant flows back to the compressor 1 without first flowing through the outdoor heat exchanger serving as the evaporator (for example, the first outdoor heat exchanger 20 in the first defrosting mode or the second outdoor heat exchanger 21 in the second defrosting mode), then flows through the inter-tube heat exchanger 12, and then flows through the outdoor heat exchanger serving as the evaporator, so that the refrigerant flows before flowing to the outdoor heat exchanger serving as the evaporator, the refrigerant passes through one flow passage of the inter-tube heat exchanger 12 first, absorbs the heat of the refrigerant in the other flow passage of the inter-tube heat exchanger 12, and evaporates, and is also beneficial to improving the defrosting and liquid returning phenomenon because the evaporation of the refrigerant can be increased outside the outdoor heat exchanger used as an evaporator.

It can be seen that by additionally arranging the inter-tube heat exchanger 12 between the first outdoor heat exchanger 20 and the second outdoor heat exchanger 21, the low-temperature and low-pressure liquid refrigerant flowing back to the compressor 1 is evaporated by using the high-temperature and high-pressure refrigerant flowing out from the compressor 1, so that the defrosting liquid return phenomenon can be effectively improved, the low-temperature and low-pressure refrigerant is prevented from being directly returned to the compressor 1 without being sufficiently evaporated in the defrosting process, the full-load output heating capacity can be immediately realized after defrosting is finished, and the temperature control precision and the operation safety of the system are improved.

Meanwhile, the added inter-tube heat exchanger 12 does not affect the operation of the first cooling mode and the first heating mode. For example, referring to fig. 3, when the heat pump system is in the cooling mode, the two refrigerant paths flowing through the first path 121 and the second path 122 of the inter-tube heat exchanger 12 are both high-temperature and high-pressure steam flowing out of the exhaust port 11, and the temperatures of the two refrigerant paths are the same, so that there is no heat exchange temperature difference between the first path 121 and the second path 122, and no heat exchange occurs, so that the inter-tube heat exchanger 12 does not or hardly interfere with the cooling process in the first cooling mode. For another example, referring to fig. 6, when the heat pump system is in the heating mode, the two refrigerant paths flowing through the first path 121 and the second path 122 of the inter-tube heat exchanger 12 are both low-temperature and low-pressure refrigerant flowing to the compressor 1 after being evaporated by the outdoor heat exchanger, and the two refrigerant paths have the same temperature, so that there is no heat exchange temperature difference between the first flow path 121 and the second flow path 122, and heat exchange is not performed, so that the inter-tube heat exchanger 12 does not or hardly interfere with the heating process in the first heating mode.

In addition, the added inter-tube heat exchanger 12 is also beneficial to improving the energy-saving effect. Specifically, since the inter-tube heat exchanger 12 can share the evaporation load, the power of the outdoor fan corresponding to the outdoor heat exchanger used as the evaporator (i.e., the first outdoor fan 24 in the first defrosting mode or the second outdoor fan 25 in the second defrosting mode) can be reduced, even referring to table 1, in some embodiments, the power of the outdoor fan corresponding to the outdoor heat exchanger used as the evaporator can be reduced to 0, and the outdoor fan corresponding to the outdoor heat exchanger used as the evaporator is shut down, so that the energy consumption of the outdoor fan can be effectively reduced, and the energy saving effect can be improved.

Referring to fig. 15, based on the heat pump system of the foregoing embodiments, the present invention further provides a control method of a heat pump system, including:

s100, determining a target operation mode of the heat pump system;

s200, controlling the operation of the switching device 300 based on the target operation mode.

In step S100, the target operation mode of the heat pump system refers to a mode in which the heat pump system needs to operate, and may be a cooling mode, a heating mode, or a defrosting mode, and the defrosting mode may include a first defrosting mode and a second defrosting mode.

In step S200, the operation of the switching device 300 is controlled based on the target operation mode, that is, the operation of the switching device 300 is controlled to switch the heat pump system to the target operation mode. Referring to fig. 11, in some embodiments, the controlling the switching device 300 action based on the target operation mode in step S200 includes at least one of:

s230, when the target operation mode is the defrosting mode, controlling the switching device 300 to operate, so that one of the first outdoor heat exchanger 20 and the second outdoor heat exchanger 21 and the indoor heat exchanger 9 are both in the condenser mode, and the other of the first outdoor heat exchanger 20 and the second outdoor heat exchanger 21 is in the evaporator mode;

s210, when the target operation mode is the cooling mode, controlling the switching device 300 to operate, so that the indoor heat exchanger 9 is in the evaporator mode, and the first outdoor heat exchanger 20 and the second outdoor heat exchanger 21 are in the condenser mode, or one of the first outdoor heat exchanger 20 and the second outdoor heat exchanger 21 is in the evaporator mode, and the other is in the condenser mode;

s220, when the target operation mode is the heating mode, the switching device 300 is controlled to operate, so that the indoor heat exchanger 9 is in the condenser mode, and the first outdoor heat exchanger 20 and the second outdoor heat exchanger 21 are in the evaporator mode, or one of the first outdoor heat exchanger 20 and the second outdoor heat exchanger 21 is in the evaporator mode, and the other is in the condenser mode.

Wherein, when the cooling mode includes the first cooling mode, step S210 includes:

the switching device 300 is controlled to operate so that the indoor heat exchanger 9 is in the evaporator mode and the first and second

outdoor heat exchangers

20 and 21 are in the condenser mode.

When the cooling mode includes the second cooling mode, step S210 includes:

the switching device 300 is controlled to operate so that the indoor heat exchanger 9 and the first outdoor heat exchanger 20 are in the evaporator mode, and the second outdoor heat exchanger 21 is in the condenser mode.

When the cooling mode includes the third cooling mode, step S210 includes:

the switching device 300 is controlled to operate so that the indoor heat exchanger 9 and the second outdoor heat exchanger 21 are in the evaporator mode and the first outdoor heat exchanger 20 is in the condenser mode.

When the heating mode includes the first heating mode, the step S220 includes:

the switching device 300 is controlled to operate so that the indoor heat exchanger 9 is in the condenser mode and the first and second

outdoor heat exchangers

20 and 21 are in the evaporator mode.

When the heating mode includes the second heating mode, the step S220 includes:

the switching device 300 is controlled to operate so that both the indoor heat exchanger 9 and the first outdoor heat exchanger 20 are in the condenser mode and the second outdoor heat exchanger 21 is in the evaporator mode.

When the heating mode includes the first heating mode, the step S220 includes:

the switching device 300 is controlled to operate so that both the indoor heat exchanger 9 and the second outdoor heat exchanger 21 are in the condenser mode and the first outdoor heat exchanger 20 is in the evaporator mode.

When the defrosting mode includes the first defrosting mode, the step S230 includes:

when the target operation mode is the first defrosting mode, the switching device 300 is controlled to operate so that the second outdoor heat exchanger 21 and the indoor heat exchanger 9 are both in the condenser mode and the first outdoor heat exchanger 20 is in the evaporator mode.

When the defrosting mode includes the second defrosting mode, the step S230 includes:

when the target operation mode is the second defrosting mode, the switching device 300 is controlled to operate, so that the first outdoor heat exchanger 20 and the indoor heat exchanger 9 are both in the condenser mode, and the second outdoor heat exchanger 21 is in the evaporator mode.

When the switching device 300 specifically includes the first switching valve 2, the second switching valve 3, the first valve 4, and the second valve 5, the operation of the switching device 300 may be controlled in S200, specifically, the operation of the first switching valve 2, the second switching valve 3, the first valve 4, and the second valve 5 may be controlled.

For example, when the target operation mode is the first defrosting mode, the first port 2D of the first switching valve 2 is controlled to communicate with the second port 2C, the third port 2E is controlled to communicate with the fourth port 2S, the first switching port 3D of the second switching valve 3 is controlled to communicate with the third switching port 3E, the second switching port 3C is controlled to communicate with the fourth switching port 3S, the first valve 4 is controlled to be closed, the second valve 5 is controlled to be opened, the second outdoor heat exchanger 21 and the indoor heat exchanger 9 are both in the condenser mode, and the first outdoor heat exchanger 20 is controlled to be in the evaporator mode.

When the target operation mode is the second defrosting mode, the first valve port 2D of the first switching valve 2 is controlled to be communicated with the third valve port 2E, the second valve port 2C of the first switching valve 2 is controlled to be communicated with the fourth valve port 2S, the first switching port 3D of the second switching valve 3 is controlled to be communicated with the second switching port 3C, the third switching port 3E of the second switching valve 3 is controlled to be communicated with the fourth switching port 3S, the first valve 4 is controlled to be opened, the second valve 5 is controlled to be closed, the first outdoor heat exchanger 20 and the indoor heat exchanger 9 are both in the condenser mode, and the second outdoor heat exchanger 21 is in the evaporator mode.

For another example, when the target operation mode is the first cooling mode, the first valve port 2D of the first switching valve 2 is controlled to be communicated with the second valve port 2C, the third valve port 2E is controlled to be communicated with the fourth valve port 2S, the first switching port 3D of the second switching valve 3 is controlled to be communicated with the second switching port 3C, the third switching port 3E is controlled to be communicated with the fourth switching port 3S, and the first valve 4 and the second valve 5 are controlled to be opened, so that the indoor heat exchanger 9 is in the evaporator mode, and the first outdoor heat exchanger 20 and the second outdoor heat exchanger 21 are in the condenser mode.

When the target operation mode is the second cooling mode, the first valve port 2D of the first switching valve 2 is controlled to be communicated with the second valve port 2C, the third valve port 2 is controlled to be communicated with the fourth valve port 2S, the first switching port 3D of the second switching valve 3 is controlled to be communicated with the third switching port 3E, the second switching port 3C is controlled to be communicated with the fourth switching port 3S, the first valve 4 is controlled to be opened, the second valve 5 is controlled to be closed, and the indoor heat exchanger 9 and the first outdoor heat exchanger 20 are in the evaporator mode, and the second outdoor heat exchanger 21 is in the condenser mode.

When the target operation mode is the third cooling mode, the first valve port 2D of the first switching valve 2 is controlled to be communicated with the third valve port 2E, the second valve port 2C of the first switching valve 2 is controlled to be communicated with the fourth valve port 2S, the first switching port 3D of the second switching valve 3 is controlled to be communicated with the second switching port 3C, the third switching port 3E of the second switching valve 3 is controlled to be communicated with the fourth switching port 3S, the first valve 4 is controlled to be closed, the second valve 5 is controlled to be opened, the indoor heat exchanger 9 and the second outdoor heat exchanger 21 are in the evaporator mode, and the first outdoor heat exchanger 20 is in the condenser mode.

For another example, when the target operation mode is the first heating mode, the first port 2D of the first switching valve 2 is controlled to communicate with the third port 2E, the second port 2C is controlled to communicate with the fourth port 2S, the first switching port 3D of the second switching valve 3 is controlled to communicate with the second switching port 3C, the third switching port 3E is controlled to communicate with the fourth switching port 3S, and both the first valve 4 and the second valve 5 are controlled to be opened, so that the indoor heat exchanger 9 is in the condenser mode, and the first outdoor heat exchanger 20 and the second outdoor heat exchanger 21 are in the evaporator mode. This step is labeled S221 in fig. 11.

When the target operation mode is the second heating mode, the first valve port 2D of the first switching valve 2 is controlled to be communicated with the third valve port 2E, the second valve port 2C of the first switching valve 2 is controlled to be communicated with the fourth valve port 2S, the first switching port 3D of the second switching valve 3 is controlled to be communicated with the second switching port 3C, the third switching port 3E of the second switching valve 3 is controlled to be communicated with the fourth switching port 3S, the first valve 4 is controlled to be opened, the second valve 5 is controlled to be closed, the indoor heat exchanger 9 and the first outdoor heat exchanger 20 are both in the condenser mode, and the second outdoor heat exchanger 21 is in the evaporator mode.

When the target operation mode is the third heating mode, the first valve port 2D of the first switching valve 2 is controlled to be communicated with the second valve port 2C, the third valve port 2E is controlled to be communicated with the fourth valve port 2S, the first switching port 3D of the second switching valve 3 is controlled to be communicated with the third switching port 3E, the second switching port 3C is controlled to be communicated with the fourth switching port 3S, the first valve 4 is controlled to be closed, the second valve 5 is controlled to be opened, the indoor heat exchanger 9 and the second outdoor heat exchanger 21 are both in the condenser mode, and the first outdoor heat exchanger 20 is in the evaporator mode.

In addition, the present invention also provides a control device of a heat pump system, which includes a memory 26 and a processor 27 coupled to the memory, wherein the processor 27 is configured to execute the control method of the foregoing embodiments based on instructions stored in the memory 26.

For example, referring to fig. 16, in some embodiments, the control device includes a memory 26, a processor 27, a communication interface 28, and a bus 29. The memory 26 is used to store instructions. The processor 27 is coupled to the memory 26 and is configured to execute control methods implementing the foregoing embodiments based on instructions stored by the memory 131. The memory 26, the processor 27 and the communication interface 28 are connected by a bus 29.

The memory 26 may be a high-speed RAM memory or a non-volatile memory (non-volatile memory) or the like. Memory 26 may also be a memory array. The storage 26 may also be partitioned, and the blocks may be combined into virtual volumes according to certain rules. The processor 27 may be a central processing unit CPU, or an application Specific Integrated circuit asic, or one or more Integrated circuits configured to implement the control method of the heat pump system of the present invention.

In still another aspect, the present invention further provides an air conditioning apparatus including the heat pump system of each of the foregoing embodiments and the control device of each of the foregoing embodiments.

Yet another aspect of the present invention also provides a computer-readable storage medium. The computer readable storage medium stores computer instructions. The computer instructions are executed by the processor to perform the control method of the foregoing embodiments.

The above description is only exemplary of the present invention and should not be taken as limiting the invention, as any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A heat pump system, comprising:

a compressor (1);

an indoor heat exchanger (9);

a first outdoor heat exchanger (20);

a second outdoor heat exchanger (21); and

a switching device (300) that controls the indoor heat exchanger (9), the first outdoor heat exchanger (20), and the second outdoor heat exchanger (21) to switch between an evaporator mode and a condenser mode by controlling on-off relationships among the first port (9a) of the indoor heat exchanger (9), the first interface (20a) of the first outdoor heat exchanger (20), and the first port (21a) of the second outdoor heat exchanger (21), and the discharge port (11) and the suction port (12) of the compressor (1);

the second port (9b) of the indoor heat exchanger (9) is connected with the second port (20b) of the first outdoor heat exchanger (20) through a first pipeline (81), and the second port (21b) of the second outdoor heat exchanger (21) is connected with the first pipeline (81) through a second pipeline (82);

the switching device (300) is configured to control both the indoor heat exchanger (9) and one of the first outdoor heat exchanger (20) and the second outdoor heat exchanger (21) to be in the condenser mode, and the other of the first outdoor heat exchanger (20) and the second outdoor heat exchanger (21) to be in the evaporator mode, when the heat pump system is in the defrost mode.

2. The heat pump system according to claim 1, wherein said switching device (300) comprises:

a first switching valve (2) including a first port (2D), a second port (2C), a third port (2E), and a fourth port (2S), the fourth port (2S) being communicated with one of the second port (2C) and the third port (2E) when the first port (2D) is communicated with the other of the second port (2C) and the third port (2E), the first port (2D) being communicated with the exhaust port (11), the second port (2C) being communicated with the first port (21a), the third port (2E) being connected with the first port (9a) through a third line (83), the fourth port (2S) being communicated with the suction port (12); and

a second switching valve (3) including a first switching port (3D), a second switching port (3C), a third switching port (3E), and a fourth switching port (3S), when the first switching port (3D) communicates with one of the second switching port (3C) and the third switching port (3E), the fourth switching port (3S) communicates with the other of the second switching port (3C) and the third switching port (3E), the first switching port (3D) communicates with the exhaust port (11), the second switching port (3C) communicates with the first port (20a), the third switching port (3E) is connected with the first port (9a) through a fourth pipeline (84), and the fourth switching port (3S) communicates with the suction port (12).

3. The heat pump system of claim 2, wherein the switching device (300) further comprises:

the first valve (4) is arranged on the third pipeline (83) and is used for controlling the on-off of the third pipeline (83); and

and the second valve (5) is arranged on the fourth pipeline (84) and is used for controlling the on-off of the fourth pipeline (84).

4. Heat pump system according to claim 2, wherein the first line (81) and the second line (82) are connected at a connection point (F), the heat pump system further comprising:

a first outdoor throttling element (22) arranged on the first pipeline (81) and positioned between the second interface (20b) and the connecting point (F); and

and a second outdoor throttling member (23) arranged on the second pipeline (82).

5. The heat pump system of claim 1, wherein the switching device (300) is further configured to at least one of:

controlling the indoor heat exchanger (9) in the evaporator mode and the first and second outdoor heat exchangers (20, 21) in the condenser mode when the heat pump system is in a cooling mode;

controlling the indoor heat exchanger (9) to be in the condenser mode and the first outdoor heat exchanger (20) and the second outdoor heat exchanger (21) to be in the evaporator mode when the heat pump system is in a heating mode.

6. Heat pump system according to claim 1, characterized in that the compressor (1) is located indoors or outdoors.

7. The heat pump system according to claims 1-6, further comprising an inter-tube heat exchanger (12), wherein a first flow channel (121) and a second flow channel (122) are arranged in the inter-tube heat exchanger (12), wherein the first port (20a) and the first port (21a) are connected to the switching device (300) through the first flow channel (121) and the second flow channel (122), respectively, or wherein the second port (20b) and the second port (21b) are connected to the indoor heat exchanger (9) through the first flow channel (121) and the second flow channel (122), respectively.

8. The heat pump system according to claim 7, wherein the second port (20b) and the second port (21b) are connected to the indoor heat exchanger (9) through the first flow passage (121) and the second flow passage (122), respectively, and the first flow passage (121) is located between a first outdoor throttle (22) and the second port (20b) of the heat pump system.

9. The heat pump system of claim 7, wherein the inter-tube heat exchanger (12) is located indoors or outdoors.

10. The heat pump system of claim 1, further comprising a first outdoor fan (24) and a second outdoor fan (25), wherein the first outdoor fan (24) and the first outdoor heat exchanger (20) are located in a first air duct, wherein the second outdoor fan (25) and the second outdoor heat exchanger (21) are located in a second air duct, and wherein the first air duct and the second air duct are independently located.

11. A control method of a heat pump system for controlling the heat pump system according to any one of claims 1 to 10, comprising:

determining a target operating mode of the heat pump system;

controlling the switching device (300) to act based on the target operation mode.

12. The control method according to claim 11, characterized in that said controlling the switching means (300) action based on the target operation mode comprises at least one of:

when the target operation mode is a defrosting mode, controlling the switching device (300) to act, so that one of the first outdoor heat exchanger (20) and the second outdoor heat exchanger (21) and the indoor heat exchanger (9) are both in the condenser mode, and the other one of the first outdoor heat exchanger (20) and the second outdoor heat exchanger (21) is in the evaporator mode;

when the target operation mode is a cooling mode, controlling the switching device (300) to act, so that the indoor heat exchanger (9) is in the evaporator mode, and the first outdoor heat exchanger (20) and the second outdoor heat exchanger (21) are in the condenser mode, or one of the first outdoor heat exchanger (20) and the second outdoor heat exchanger (21) is in the evaporator mode, and the other is in the condenser mode;

when the target operation mode is a heating mode, controlling the switching device (300) to act, so that the indoor heat exchanger (9) is in the condenser mode, and the first outdoor heat exchanger (20) and the second outdoor heat exchanger (21) are in the evaporator mode, or one of the first outdoor heat exchanger (20) and the second outdoor heat exchanger (21) is in the evaporator mode, and the other is in the condenser mode.

13. The control method according to claim 12, wherein when the target operation mode is a defrosting mode, controlling the switching device (300) to act so that one of the first outdoor heat exchanger (20) and the second outdoor heat exchanger (21) and the indoor heat exchanger (9) are both in a condenser mode, and the other of the first outdoor heat exchanger (20) and the second outdoor heat exchanger (21) is in an evaporator mode comprises at least one of:

when the target operation mode is a first defrosting mode, controlling the switching device (300) to act, so that the second outdoor heat exchanger (21) and the indoor heat exchanger (9) are both in the condenser mode, and the first outdoor heat exchanger (20) is in the evaporator mode;

and when the target operation mode is a defrosting mode, controlling the switching device (300) to act, so that the first outdoor heat exchanger (20) and the indoor heat exchanger (9) are both in the condenser mode, and the second outdoor heat exchanger (21) is in the evaporator mode.

14. A control method of a heat pump system for controlling the heat pump system according to any one of claims 3 to 10, comprising:

determining a target operating mode of the heat pump system;

and controlling the action of the first switching valve (2), the second switching valve (3), the first valve (4) and the second valve (5) based on the target operation mode.

15. The control method according to claim 14, characterized in that the act of controlling the first switching valve (2), the second switching valve (3), the first valve (4) and the second valve (5) based on the target operation mode comprises at least one of:

when the target operation mode is a first defrosting mode, controlling a first valve port (2D) of the first switching valve (2) to be communicated with a second valve port (2C), controlling a third valve port (2E) to be communicated with a fourth valve port (2S), controlling a first switching port (3D) of the second switching valve (3) to be communicated with a third switching port (3E), controlling a second switching port (3C) to be communicated with a fourth switching port (3S), controlling the first valve (4) to be closed, controlling the second valve (5) to be opened, enabling the second outdoor heat exchanger (21) and the indoor heat exchanger (9) to be in the condenser mode, and controlling the first outdoor heat exchanger (20) to be in the evaporator mode;

when the target operation mode is a second defrosting mode, controlling a first valve port (2D) of the first switching valve (2) to be communicated with a third valve port (2E), controlling a second valve port (2C) to be communicated with a fourth valve port (2S), controlling a first switching port (3D) of the second switching valve (3) to be communicated with a second switching port (3C), controlling a third switching port (3E) to be communicated with a fourth switching port (3S), controlling the first valve (4) to be opened, controlling the second valve (5) to be closed, enabling the first outdoor heat exchanger (20) and the indoor heat exchanger (9) to be in the condenser mode, and controlling the second outdoor heat exchanger (21) to be in the evaporator mode;

when the target operation mode is a first refrigeration mode, controlling a first valve port (2D) of the first switching valve (2) to be communicated with a second valve port (2C), controlling a third valve port (2E) to be communicated with a fourth valve port (2S), controlling a first switching port (3D) of the second switching valve (3) to be communicated with a second switching port (3C), controlling a third switching port (3E) to be communicated with a fourth switching port (3S), controlling the first valve (4) and the second valve (5) to be opened, enabling the indoor heat exchanger (9) to be in the evaporator mode, and controlling the first outdoor heat exchanger (20) and the second outdoor heat exchanger (21) to be in the condenser mode;

when the target operation mode is a second refrigeration mode, controlling a first valve port (2D) of the first switching valve (2) to be communicated with a second valve port (2C), controlling a third valve port (2) to be communicated with a fourth valve port (2S), controlling a first switching port (3D) of the second switching valve (3) to be communicated with a third switching port (3E), controlling a second switching port (3C) to be communicated with a fourth switching port (3S), controlling the first valve (4) to be opened, controlling the second valve (5) to be closed, enabling the indoor heat exchanger (9) and the first outdoor heat exchanger (20) to be in the evaporator mode, and controlling the second outdoor heat exchanger (21) to be in the condenser mode;

when the target operation mode is a third cooling mode, controlling the first valve port (2D) of the first switching valve (2) to be communicated with the third valve port (2E), the second valve port (2C) to be communicated with the fourth valve port (2S), controlling the first switching port (3D) of the second switching valve (3) to be communicated with the second switching port (3C), the third switching port (3E) to be communicated with the fourth switching port (3S), controlling the first valve (4) to be closed, controlling the second valve (5) to be opened, enabling the indoor heat exchanger (9) and the second outdoor heat exchanger (21) to be in the evaporator mode, and controlling the first outdoor heat exchanger (20) to be in the condenser mode;

when the target operation mode is a first heating mode, controlling a first valve port (2D) of the first switching valve (2) to be communicated with a third valve port (2E), a second valve port (2C) to be communicated with a fourth valve port (2S), controlling a first switching port (3D) of the second switching valve (3) to be communicated with a second switching port (3C), controlling a third switching port (3E) to be communicated with a fourth switching port (3S), and controlling the first valve (4) and the second valve (5) to be opened, so that the indoor heat exchanger (9) is in the condenser mode, and the first outdoor heat exchanger (20) and the second outdoor heat exchanger (21) are in the evaporator mode;

when the target operation mode is a second heating mode, controlling the first valve port (2D) of the first switching valve (2) to be communicated with the third valve port (2E), the second valve port (2C) to be communicated with the fourth valve port (2S), controlling the first switching port (3D) of the second switching valve (3) to be communicated with the second switching port (3C), the third switching port (3E) to be communicated with the fourth switching port (3S), controlling the first valve (4) to be opened, controlling the second valve (5) to be closed, enabling the indoor heat exchanger (9) and the first outdoor heat exchanger (20) to be in the condenser mode, and controlling the second outdoor heat exchanger (21) to be in the evaporator mode;

when the target operation mode is a third heating mode, controlling the first valve port (2D) of the first switching valve (2) to be communicated with the second valve port (2C), the third valve port (2E) to be communicated with the fourth valve port (2S), controlling the first switching port (3D) of the second switching valve (3) to be communicated with the third switching port (3E), controlling the second switching port (3C) to be communicated with the fourth switching port (3S), controlling the first valve (4) to be closed, and controlling the second valve (5) to be opened, so that the indoor heat exchanger (9) and the second outdoor heat exchanger (21) are both in the condenser mode, and the first outdoor heat exchanger (20) is in the evaporator mode.

16. A control device of a heat pump system, comprising a memory (26) and a processor (27) coupled to the memory, the processor (27) being configured to perform the control method according to any one of claims 11-15 based on instructions stored in the memory (26).

17. An air conditioning apparatus comprising a heat pump system according to any one of claims 1 to 10 and a control device according to claim 16.

18. A computer-readable storage medium storing computer instructions for execution by a processor of a control method according to any one of claims 11-15.