WO2025086690A1 - Heat pump system control method, and heat pump system and storage medium - Google Patents

Abstract

A heat pump system control method, and a heat pump system and a storage medium. The heat pump system has at least two of a first defrosting mode, a second defrosting mode and a third defrosting mode, wherein in the first defrosting mode, a refrigerant duct in an energy storage apparatus (7) of the heat pump system is in an evaporation state; in the second defrosting mode, an indoor heat exchanger (21) of the heat pump system is in an evaporation state; and in the third defrosting mode, both the refrigerant duct in the energy storage apparatus (7) and the indoor heat exchanger (21) are in an evaporation state. The method comprises: acquiring first state information of an energy storage apparatus (7) in a heat pump system and/or second state information of an indoor heat exchanger (21) in the heat pump system; determining a target defrosting mode for the heat pump system on the basis of the first state information and/or the second state information; and controlling the heat pump system to operate in the target defrosting mode, so as to defrost an outdoor unit of the heat pump system.

Description

Heat pump system control method, heat pump system and storage medium

This application claims priority to Chinese patent application No. 202311413030.0 filed on October 27, 2023, the entire contents of which are incorporated by reference into this application.

Technical Field

The present application relates to the technical field of heat pumps, and in particular to a control method for a heat pump system, a heat pump system, and a storage medium.

Background Art

When the heat pump system is running in heating mode, the outdoor heat exchanger is in a heat absorption state. When running for a long time in a low temperature environment, the outdoor heat exchanger is prone to frost. When the frost reaches a certain thickness, it is necessary to enter the defrost mode to ensure the heating capacity of the system.

However, the target heat pump system generally has only a single defrost mode, which is to directly switch the indoor heat exchanger to the evaporation state and the outdoor heat exchanger to the condensation state. The heat absorbed by the defrost is all absorbed by the indoor environment. However, this method can easily cause a sharp drop in indoor temperature and affect indoor comfort.

Technical issues

The main purpose of the present application is to provide a control method for a heat pump system, a heat pump system and a storage medium, aiming to ensure the defrosting effect of the system while reducing indoor temperature fluctuations during the defrosting process and improving indoor comfort.

Technical Solutions

To achieve the above-mentioned object, the present application provides a control method for a heat pump system, wherein the heat pump system has at least two of a first defrost mode, a second defrost mode and a third defrost mode, wherein in the first defrost mode, a refrigerant pipe in an energy storage device of the heat pump system is in an evaporating state, in the second defrost mode, an indoor heat exchanger of the heat pump system is in an evaporating state, and in the third defrost mode, both the refrigerant pipe in the energy storage device and the indoor heat exchanger are in an evaporating state, and the control method for the heat pump system comprises the following steps:

When the heat pump system runs to meet the defrosting condition, obtaining first state information of the energy storage device in the heat pump system and/or second state information of the indoor heat exchanger;

determining a target defrost mode of the heat pump system according to the first state information and/or the second state information;

The heat pump system is controlled to run the target defrost mode to defrost an outdoor unit of the heat pump system.

In one embodiment, the first state information includes the energy storage medium temperature of the energy storage device and/or the capacity state of the energy storage device, and the step of determining the target defrost mode of the heat pump system according to the first state information includes:

A target defrosting mode of the heat pump system is determined according to the energy storage medium temperature and/or the capacity state.

In one embodiment, the step of determining the target defrost mode of the heat pump system according to the energy storage medium temperature and/or the capacity state comprises:

When the temperature of the energy storage medium is less than or equal to a preset temperature, determining the second defrost mode as the target defrost mode; and/or

When the temperature of the energy storage medium is greater than the preset temperature, determining the first defrost mode as the target defrost mode; and/or

When the temperature of the energy storage medium is greater than the preset temperature and the capacity of the energy storage device meets the preset conditions required for defrosting of the outdoor unit, determining the first defrost mode as the target defrost mode; and/or

When the temperature of the energy storage medium is greater than the preset temperature and the capacity of the energy storage device does not meet the preset condition, the third defrost mode is determined to be the target defrost mode.

In one embodiment, the preset condition includes: a ratio of a rated capacity of the energy storage device to a rated capacity of the outdoor unit is greater than or equal to a preset value.

In one embodiment, the rated capacity of the energy storage device is positively correlated with the energy storage capacity of the energy storage device.

In one embodiment, the first state information further includes whether the heat pump system is installed with the energy storage device, and the step of determining the target defrosting mode of the heat pump system according to the first state information includes:

When the heat pump system has been installed with the energy storage device, determining a target defrosting mode of the heat pump system according to the temperature of the energy storage medium and/or the capacity state;

When the heat pump system is not equipped with the energy storage device, the second defrost mode is determined to be the target defrost mode.

In one embodiment, the first state information includes the heat exchange state of the energy storage device, the second state information includes the heat exchange state of the indoor heat exchanger, and the step of determining the target defrosting mode of the heat pump system according to the first state information and the second state information includes:

When the indoor heat exchanger is in a condensing state and the refrigerant pipe in the energy storage device is not in a condensing state, determining that the second defrosting mode is the target defrosting mode;

When the refrigerant pipes in the indoor heat exchanger and the energy storage device are both in a condensing state, or when the indoor heat exchanger is not in a condensing state and the refrigerant pipes in the energy storage device are in a condensing state, the first defrost mode or the third defrost mode is determined as the target defrost mode.

In one embodiment, the heat pump system includes a refrigerant main circuit and a refrigerant branch circuit connected to the refrigerant main circuit, the refrigerant branch circuit includes an energy storage device and a first control valve, the refrigerant main circuit includes a compressor, an indoor unit, an outdoor heat exchanger, a throttling device and a reversing component, the indoor unit includes the indoor heat exchanger and the second control valve, the indoor unit, the second control valve, the throttling device and the outdoor heat exchanger are connected in sequence, the pipeline between the indoor unit and the throttling device is connected to one end of the refrigerant branch circuit, the other end of the refrigerant branch circuit, the indoor unit, the outdoor heat exchanger, the exhaust port of the compressor and the return air port of the compressor are all connected to the reversing component, and the step of controlling the heat pump system to operate the target defrost mode to defrost the outdoor unit of the heat pump system includes:

When the heat pump system operates in the first defrost mode, the reversing assembly is controlled to operate so that the exhaust port of the compressor is connected to the outdoor heat exchanger, the refrigerant branch and the indoor unit are connected to the return air port of the compressor, the first control valve is controlled to be opened, and the second control valve is controlled to be closed;

When the heat pump system operates in the second defrost mode, the reversing assembly is controlled to operate so that the exhaust port of the compressor is connected to the outdoor heat exchanger, the refrigerant branch and the indoor unit are connected to the return air port of the compressor, the first control valve is controlled to be closed, and the second control valve is controlled to be opened;

When the heat pump system runs the third defrost mode, the reversing component is controlled to operate so that the exhaust port of the compressor is connected to the outdoor heat exchanger, the refrigerant branch and the indoor unit are connected to the return air port of the compressor, and the first control valve and the second control valve are controlled to be open.

In one embodiment, the reversing assembly includes a first reversing valve, a second reversing valve and a switching valve, the exhaust port, the return air port and the indoor heat exchanger are all connected to the first reversing valve, the exhaust port, the return air port and the outdoor heat exchanger are all connected to the second reversing valve, the exhaust port, the return air port and the refrigerant branch are all connected to the switching valve, and the step of controlling the reversing assembly to operate so that the exhaust port of the compressor is connected to the outdoor heat exchanger, and the refrigerant branch and the indoor unit are all connected to the return air port of the compressor includes:

The first reversing valve is controlled to operate in a first valve position so that the return air port is connected to the indoor unit, the second reversing valve is controlled to operate in a third valve position so that the exhaust port is connected to the outdoor heat exchanger, and the switching valve is controlled to operate in a first switching state so that the return air port is connected to the refrigerant branch.

In addition, in order to achieve the above-mentioned purpose, the present application also proposes a heat pump system, which includes: a memory, a processor, and a control program of the heat pump system stored in the memory and executable on the processor, and when the control program of the heat pump system is executed by the processor, the steps of the control method of the heat pump system as described in any of the above items are implemented.

In addition, in order to achieve the above-mentioned purpose, the present application also proposes a storage medium, on which a control program of a heat pump system is stored. When the control program of the heat pump system is executed by a processor, the steps of the control method of the heat pump system as described in any of the above items are implemented.

Beneficial Effects

The present application proposes a control method for a heat pump system, in which a target defrost mode for the heat pump system to be operated is selected from at least two defrost modes, namely, a first defrost mode, a second defrost mode and a third defrost mode, according to the state of an energy storage device and/or an indoor heat exchanger in the heat pump system. Under some working conditions, the heat required for the defrost operation of the heat pump system can be partially or completely absorbed from the heat stored in the energy storage device, which can effectively reduce the situation in which the heat pump system absorbs all the heat from the indoor environment during the defrost operation, reduce temperature loss in the indoor environment, thereby ensuring the defrost effect of the system while reducing indoor temperature fluctuations during the defrost process and improving indoor comfort.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG1 is a schematic diagram of the structure of an embodiment of a heat pump system of the present application and a schematic diagram of the refrigerant flow direction in a heat storage mode;

FIG2 is a schematic diagram of the structure of an embodiment of a heat pump system of the present application and a schematic diagram of the refrigerant flow direction in a heating mode;

3 is a schematic diagram of the structure of an embodiment of a heat pump system of the present application and a schematic diagram of the refrigerant flow in heating and heat storage modes;

FIG4 is a schematic diagram of the structure of an embodiment of a heat pump system of the present application and a schematic diagram of the refrigerant flow direction in a first defrosting mode;

FIG5 is a schematic diagram of the structure of an embodiment of a heat pump system of the present application and a schematic diagram of the refrigerant flow direction in a second defrosting mode;

FIG6 is a schematic diagram of the structure of an embodiment of a heat pump system of the present application and a schematic diagram of the refrigerant flow direction in a third defrosting mode;

FIG7 is a schematic diagram of the hardware structure involved in the operation of an embodiment of a heat pump system of the present application;

FIG8 is a flow chart of an embodiment of a control method for a heat pump system of the present application;

FIG9 is a flow chart of another embodiment of a control method for a heat pump system of the present application;

FIG10 is a schematic diagram of a detailed process of step S21 in FIG9 ;

FIG. 11 is a flow chart of another embodiment of a control method for a heat pump system of the present application.

The realization of the purpose, functional features and advantages of this application will be further explained in conjunction with embodiments and with reference to the accompanying drawings.

Embodiments of the present invention

It should be understood that the specific embodiments described herein are only used to explain the present application and are not used to limit the present application.

An embodiment of the present application provides a heat pump system.

In the embodiment of the present application, referring to FIGS. 1 to 7 , the heat pump system includes a control device 100, a refrigerant main circuit and a refrigerant branch circuit, wherein the refrigerant main circuit includes a compressor 1, an indoor unit, an outdoor heat exchanger 3, a throttling device 4, an outdoor unit and a reversing assembly 5, and the refrigerant branch circuit includes an energy storage device 7 and a first control valve 8. The indoor unit, the reversing assembly 5, the compressor 1, the throttling device 4 and the first control valve 8 are all connected to the control device 100. Among them, the outdoor unit includes the outdoor heat exchanger 3, the throttling device 4, the reversing assembly 5 and the first control valve 8 mentioned above. The throttling device 4 and the first control valve 8 can be electronic expansion valves.

In one embodiment, the energy storage device 7 is loaded with an energy storage medium, and the energy storage medium can absorb and store the energy of the refrigerant when the refrigerant flows through the energy storage device 7. The energy storage device 7 is a water tank.

In one embodiment, the number of the indoor units is more than one, and the more than one indoor units can be connected in parallel. Different indoor units are arranged in different indoor spaces to adjust the indoor environment of different indoor spaces.

The indoor unit includes an indoor heat exchanger 21 and a second control valve 22 connected in series with the indoor heat exchanger 21. The second control valve 22 is connected to the control device 100, and the control device 100 can be used to control the refrigerant flow through the indoor heat exchanger 21. The second control valve 22 can be an electronic expansion valve.

The indoor unit, the throttling device 4 and the outdoor heat exchanger 3 are connected in sequence, and the pipeline between the throttling device 4 and the indoor unit is connected to one end of the refrigerant branch. The indoor unit, the outdoor heat exchanger 3, the exhaust port of the compressor 1 and the return air port of the compressor 1 are all connected to the reversing component 5. The reversing component 5 can be used to switch the connection state between the indoor unit and the outdoor heat exchanger 3 and the exhaust port of the compressor 1 and the return air port of the compressor 1.

In one embodiment, the reversing assembly 5 includes a first reversing valve 51 and a second reversing valve 52. The exhaust port of the compressor 1, the return air port of the compressor 1, and the indoor unit are respectively connected to different valve ports of the first reversing valve 51, and the exhaust port of the compressor 1, the return air port of the compressor 1, and the outdoor heat exchanger 3 are respectively connected to different valve ports of the second reversing valve 52. In one implementation of this embodiment, the first reversing valve 51 is a first four-way valve, and the second reversing valve 52 is a second four-way valve. In another implementation of this embodiment, the first reversing valve 51 is a first three-way valve, and the second reversing valve 52 is a second three-way valve.

The first reversing valve 51 has a first valve position and a second valve position. In the first valve position, the return air port of the compressor 1 is connected to the indoor heat exchanger 21, and the exhaust port of the compressor 1 is blocked from the indoor heat exchanger 21. In the second valve position, the return air port of the compressor 1 is blocked from the indoor heat exchanger 21, and the exhaust port of the compressor 1 is connected to the indoor heat exchanger 21.

The second reversing valve 52 has a third valve position and a fourth valve position. In the third valve position, the exhaust port of the compressor 1 is connected to the outdoor heat exchanger 3, and the return air port of the compressor 1 is blocked from the outdoor heat exchanger 3; in the fourth valve position, the exhaust port of the compressor 1 is blocked from the outdoor heat exchanger 3, and the return air port of the compressor 1 is connected to the outdoor heat exchanger 3.

In some embodiments, the reversing assembly 5 may further include a switching valve 53, and the reversing assembly 5 (the switching valve 53) may be used to switch the connection state between the energy storage device 7 and the exhaust port of the compressor 1 and the return port of the compressor 1. The refrigerant branch, the exhaust port of the compressor 1, and the return port of the compressor 1 are all connected to the switching valve 53. The switching valve 53 may be a three-way valve or a four-way valve, and the switching valve 53 includes a first switching state and a second switching state; when the switching valve 53 is in the first switching state, the return port of the compressor 1 is connected to the energy storage device 7; when the switching valve 53 is in the second switching state, the exhaust port of the compressor 1 is connected to the energy storage device 7.

Through the regulation of the first reversing valve 51, the second reversing valve 52, the first control valve 8, the second control valve 22 and the switching valve 53, the operation modes of the heat pump system include but are not limited to the following modes:

In the heat storage mode, referring to FIG. 1 , the first reversing valve 51 operates at the first valve position, the second reversing valve 52 operates at the fourth valve position, the switching valve 53 is in the second switching state, the second control valve 22 is closed, and the first control valve 8 is opened. If the reversing assembly 5 includes a switching valve, the switching valve is in the second switching state, the exhaust port of the compressor 1 is connected to the energy storage device 7, and all the refrigerant discharged from the compressor 1 flows into the refrigerant branch. The heat of the refrigerant flowing into the refrigerant branch is stored in the energy storage device 7 when flowing through the energy storage device 7. The refrigerant flowing out of the refrigerant branch flows through the throttling device 4 and the outdoor heat exchanger 3 in turn and then flows back to the compressor 1. In the first mode, the indoor heat exchanger 21 stops heat exchange, the outdoor heat exchanger 3 is in an evaporating state, and all heat is used for heat storage of the energy storage device 7. In the first mode, the energy storage device 7 can be heat stored separately. Among them, if there is a switching valve 53, the switching valve 53 is in the second switching state.

In the heating mode, referring to FIG. 2 , the first reversing valve 51 operates at the second valve position, the second reversing valve 52 operates at the fourth valve position, the switching valve 53 is in the second switching state, the first control valve 8 is closed, and the second control valve 22 is opened. The refrigerant discharged from the compressor 1 flows through the indoor heat exchanger 21, the second control valve 22, the throttling device 4, and the outdoor heat exchanger 3 in sequence and then flows back to the compressor 1. In the fifth mode, the indoor heat exchanger 21 is in a condensing state and the outdoor heat exchanger 3 is in an evaporating state. In the fifth mode, when the indoor space regulated by the indoor unit has a heat exchange demand, the indoor fan in the indoor unit can be turned on to drive the indoor air to exchange heat with the indoor heat exchanger 21; in the fifth mode, when the indoor space regulated by the indoor unit does not have a heat exchange demand, the indoor fan in the indoor unit can be turned off. In the fifth mode, the indoor environment can be heated while the energy storage device 7 stops storing heat.

In the heating and heat storage mode, referring to FIG3 , the first reversing valve 51 operates at the second valve position, the second reversing valve 52 operates at the fourth valve position, the switching valve 53 is in the second switching state, the first control valve 8 is opened, the second control valve 22 is opened, and a part of the refrigerant discharged from the compressor 1 flows through the indoor heat exchanger 21, the second control valve 22, the throttling device 4 and the outdoor heat exchanger 3 in sequence and then flows back to the compressor 1; another part of the refrigerant discharged from the compressor 1 flows into the refrigerant branch, and the heat is stored in the energy storage device 7 when the refrigerant flows through the energy storage device 7. The refrigerant flowing out of the refrigerant branch merges with the refrigerant flowing out of the indoor unit and flows through the throttling device 4 and the outdoor heat exchanger 3 in sequence and then flows back to the compressor 1. In the sixth mode, the indoor heat exchanger 21 is in a condensing state and the outdoor heat exchanger 3 is in an evaporating state. In the sixth mode, when the indoor space regulated by the indoor unit has a heat exchange demand, the indoor fan in the indoor unit can be turned on to drive the indoor air to exchange heat with the indoor heat exchanger 21; in the sixth mode, when the indoor space regulated by the indoor unit does not have a heat exchange demand, the indoor fan in the indoor unit can be turned off. In the sixth mode, the indoor environment can be heated while the energy storage device 7 stores heat. Among them, if there is a switching valve 53, the switching valve 53 is in the second switching state.

In the first defrost mode, referring to FIG. 4 , the first reversing valve 51 operates at the first valve position, the second reversing valve 52 operates at the third valve position, the switching valve 53 is in the first switching state, the first control valve 8 is opened, and the second control valve 22 is closed. The exhaust port of the compressor 1 is connected to the outdoor heat exchanger 3. The refrigerant discharged from the compressor 1 flows through the outdoor heat exchanger 3 and the throttling device 4 in sequence and then all flows into the refrigerant branch. The refrigerant flowing into the refrigerant branch is in an evaporating state when flowing through the energy storage device 7 and absorbs heat from the energy storage medium in the energy storage device 7. The refrigerant flowing out of the refrigerant branch flows back to the compressor 1. In the first defrost mode, the outdoor heat exchanger 3 is in a condensing state to release heat to melt the frost in the outdoor unit, and the refrigerant pipeline in the energy storage device 7 is in an evaporating state to absorb heat for defrosting the outdoor unit.

In the second defrost mode, referring to FIG. 5 , the first reversing valve 51 operates at the first valve position, the second reversing valve 52 operates at the third valve position, the switching valve 53 is in the first switching state, the first control valve 8 is opened, and the second control valve 22 is closed, the exhaust port of the compressor 1 is connected to the outdoor heat exchanger 3, and the refrigerant discharged from the compressor 1 flows through the outdoor heat exchanger 3 and the throttling device 4 in sequence and then all flows into the indoor unit, and the refrigerant flowing into the indoor unit absorbs the heat in the indoor environment and then flows back to the compressor 1. In the second defrost mode, the outdoor heat exchanger 3 is in a condensing state to release heat to melt the frost in the outdoor unit, and the indoor heat exchanger 21 is in an evaporating state to absorb heat for defrosting the outdoor unit.

In the third defrost mode, referring to FIG. 6 , the first reversing valve 51 operates at the first valve position, the second reversing valve 52 operates at the third valve position, the switching valve 53 is in the first switching state, the first control valve 8 is opened, and the second control valve 22 is closed. The exhaust port of the compressor 1 is connected to the outdoor heat exchanger 3. The refrigerant discharged from the compressor 1 flows through the outdoor heat exchanger 3 and the throttling device 4 in sequence and then flows into the indoor unit and the refrigerant branch respectively. The refrigerant flowing into the refrigerant branch is in an evaporating state when flowing through the energy storage device 7 and absorbs heat from the energy storage medium in the energy storage device 7. The refrigerant flowing into the indoor unit is in an evaporating state and absorbs heat from the indoor environment. The refrigerant flowing out of the indoor unit and the refrigerant branch flows back to the compressor 1. In the third defrost mode, the outdoor heat exchanger 3 is in a condensing state to release heat to melt the frost in the outdoor unit, while the indoor heat exchanger 21 and the energy storage device 7 can absorb heat for defrosting the outdoor unit.

In other embodiments, the first reversing valve 51 and the second reversing valve 52 may also be replaced by a third four-way valve, and the exhaust port of the compressor 1, the return air port of the compressor 1, the indoor heat exchanger 21 and the outdoor heat exchanger 3 are respectively connected to different valve ports of the third four-way valve.

7 , the heat pump system further includes a temperature detection module 01 , which is connected to the control device 100 . The temperature detection module 01 may be disposed inside the energy storage device 7 to detect the temperature of the energy storage medium of the energy storage device 7 .

In the embodiment of the present application, referring to FIG. 7 , the control device 100 of the heat pump system includes: a processor 1001, such as a CPU, a memory 1002, and a timer 1003. Among them, these components are connected and communicated through a communication bus. The memory 1002 can be a high-speed RAM memory or a stable memory (non-volatile memory), such as a disk memory. The memory 1002 can also be a storage device independent of the aforementioned processor 1001.

Those skilled in the art will appreciate that the device structure shown in FIG. 7 does not constitute a limitation on the device, and may include more or fewer components than shown, or a combination of certain components, or a different arrangement of components.

As shown in FIG. 7 , the memory 1002 as a computer storage medium may include a control program of the heat pump system.

In the device shown in FIG. 7 , the processor 1001 can be used to call the control program of the heat pump system stored in the memory 1002 and execute the relevant steps of the control method of the heat pump system in the following embodiment.

The embodiment of the present application also provides a control method of a heat pump system, which is applied to the above-mentioned heat pump system.

Referring to FIG8 , an embodiment of a control method for the heat pump system of the present application is proposed. In one embodiment, the heat pump system has at least two of a first defrost mode, a second defrost mode, and a third defrost mode. In the first defrost mode, the refrigerant pipe in the energy storage device of the heat pump system is in an evaporating state. In the second defrost mode, the indoor heat exchanger of the heat pump system is in an evaporating state. In the third defrost mode, the refrigerant pipe in the energy storage device and the indoor heat exchanger are both in an evaporating state. The first defrost mode, the second defrost mode, and the third defrost mode here may specifically be the first defrost mode, the second defrost mode, and the third defrost mode mentioned above. Here, the refrigerant pipe in the energy storage device is connected to the energy storage medium for heat exchange. When the refrigerant pipe in the energy storage device is in an evaporating state, the refrigerant flowing through can absorb the heat in the energy storage medium. The control method of the heat pump system includes:

Step S10, when the heat pump system runs to meet the defrosting condition, obtaining the first state information of the energy storage device in the heat pump system and/or the second state information of the indoor heat exchanger;

The first state information and the second state information are both state information indicating the amount of heat that the corresponding device is allowed to provide to the outdoor unit in the evaporation state.

The first status information includes but is not limited to: whether the heat pump system is equipped with an energy storage device, whether the energy storage device is damaged, the temperature status of the energy storage device, the capacity status of the energy storage device, the relationship between the energy storage medium temperature of the energy storage device and the indoor ambient temperature, etc.

The second state information includes but is not limited to: whether the indoor heat exchanger is in a condensing state, the temperature state of the indoor environment where the indoor heat exchanger is located, and the like.

In one embodiment, the energy storage device can store the heat of the refrigerant discharged by the compressor. For example, when the switching valve is operated in the second switching state and the first control valve is opened, the refrigerant discharged by the compressor flows into the energy storage device, and the energy storage medium in the energy storage device absorbs the heat in the refrigerant and stores it; for example, when the energy storage device is connected in parallel with the indoor heat exchanger, a part of the heat of the refrigerant discharged by the compressor can be stored in the heating mode. In other embodiments, the energy storage device can also be connected to the outer wall of the compressor for heat exchange to store the heat generated when the compressor is working.

When the heat pump system runs in a preset mode and reaches the defrosting condition, step S10 here can be executed. In the preset mode, the outdoor heat exchanger is in an evaporating state. The preset mode may include but is not limited to the above-mentioned heating mode, heat storage mode, or heating and heat storage mode. For example, the defrosting condition may include that the outdoor ambient temperature is less than or equal to the preset ambient temperature and/or the outdoor heat exchanger is less than or equal to the preset heat exchanger temperature, etc.

Step S20, determining a target defrosting mode of the heat pump system according to the first state information and/or the second state information;

Specifically, a correspondence between the first state information and/or the second state information and the target defrost mode can be established in advance. The correspondence may include a calculation relationship, a mapping relationship, etc. Based on the correspondence, the target defrost mode corresponding to the current first state information and/or the second state information can be determined.

In one embodiment, different first state information corresponds to different first characterization values, and different second state information corresponds to different second characterization values. A first evaluation value corresponding to the first defrost mode, a second evaluation value corresponding to the second defrost mode, and a third evaluation value corresponding to the third defrost mode are calculated based on the first characterization value and/or the second characterization value, and the defrost mode with the largest value among the first evaluation value, the second evaluation value and the third evaluation value is taken as the target defrost mode.

In one embodiment, first preset state information corresponding to the energy storage device and/or the indoor heat exchanger corresponding to the first defrost mode, second preset state information corresponding to the energy storage device and/or the indoor heat exchanger corresponding to the second defrost mode, and third preset state information corresponding to the energy storage device and/or the indoor heat exchanger corresponding to the third defrost mode can be pre-set. When the first state information and/or the second state information matches the first preset state information, the first defrost mode is determined to be the target defrost mode. When the first state information and/or the second state information matches the second preset state information, the second defrost mode is determined to be the target defrost mode. When the first state information and/or the second state information matches the third preset state information, the third defrost mode is determined to be the target defrost mode.

Step S30, controlling the heat pump system to run the target defrost mode to defrost the outdoor unit of the heat pump system.

When the target defrost mode is the first defrost mode, the heat pump system is controlled to run the first defrost mode; when the target defrost mode is the second defrost mode, the heat pump system is controlled to run the second defrost mode; when the target defrost mode is the third defrost mode, the heat pump system is controlled to run the third defrost mode.

In the first defrost mode, the second defrost mode and the third defrost mode, the outdoor heat exchanger is in a condensing state, and the refrigerant can release heat to melt the frost in the outdoor unit.

A control method for a heat pump system is proposed in an embodiment of the present application. In the method, a target defrost mode for the heat pump system to be operated is selected from at least two defrost modes, namely, a first defrost mode, a second defrost mode and a third defrost mode, according to the state of an energy storage device and/or an indoor heat exchanger in the heat pump system. Under some working conditions, the heat required for the defrost operation of the heat pump system can be partially or completely absorbed from the heat stored in the energy storage device, which can effectively reduce the situation in which the heat pump system absorbs all the heat from the indoor environment during the defrost operation, reduce the temperature loss in the indoor environment, thereby ensuring the defrost effect of the system while reducing the indoor temperature fluctuation during the defrost process, thereby improving indoor comfort.

Further, based on the above embodiment, another embodiment of the control method of the heat pump system of the present application is proposed. In one embodiment, the first state information includes the energy storage medium temperature of the energy storage device and/or the capacity state of the energy storage device. Referring to FIG. 9 , the step S20 includes:

Step S21, determining a target defrosting mode of the heat pump system according to the energy storage medium temperature and/or the capacity state.

The temperature of the energy storage medium is specifically detected by the temperature detection module provided in the above-mentioned energy storage device.

The capacity state can be obtained by reading pre-stored parameters, or calculated by pre-stored parameters of the energy storage device, or determined by monitoring the current state parameters of the energy storage device.

Different energy storage medium temperatures and/or different capacity states correspond to different target defrosting modes.

Specifically, when the temperature and/or capacity state of the energy storage medium meets the first condition, the first defrost mode is determined as the target defrost mode; when the temperature and/or capacity state of the energy storage medium meets the second condition, the second defrost mode is determined as the target defrost mode; when the temperature and/or capacity state of the energy storage medium meets the third condition, the third defrost mode is determined as the target defrost mode.

In one embodiment, the temperature and/or capacity state of the energy storage medium can accurately reflect the amount of heat that the energy storage device can provide to the outdoor heat exchanger during the defrosting process. Therefore, selecting a target defrost mode based on the temperature and/or capacity state of the energy storage medium can accurately reflect the defrosting capacity of the energy storage device, which is beneficial to improving the accuracy of the target defrost mode, thereby achieving an effective balance between indoor comfort and defrosting effect.

In one embodiment, referring to FIG. 10 , step S21 includes:

Step S211, when the temperature of the energy storage medium is less than or equal to a preset temperature, determining that the second defrost mode is the target defrost mode;

The preset temperature is specifically the minimum energy storage medium temperature required for defrosting of the outdoor unit. The preset temperature may be a preset fixed temperature, or a temperature determined according to outdoor environmental parameters and/or a fan speed of an outdoor fan corresponding to an outdoor heat exchanger.

Step S212, when the temperature of the energy storage medium is greater than the preset temperature and the capacity of the energy storage device meets the preset conditions required for defrosting of the outdoor unit, determining the first defrost mode as the target defrost mode;

The preset conditions may include a target interval that the capacity needs to reach or a target relationship with a target parameter threshold, etc.

In one embodiment, the preset condition includes: the ratio of the rated capacity of the energy storage device to the rated capacity of the outdoor unit is greater than or equal to a preset value. The rated capacity of the energy storage device is positively correlated with the energy storage capacity of the energy storage device. The preset value is different for different models of heat pump systems. In one implementation, the rated capacity of the energy storage device can be calculated by the energy storage capacity; in another embodiment, the interval in which the energy storage capacity is located can be determined, and the rated capacity of the energy storage device can be determined based on the interval. For example, the relationship between the energy storage capacity and the rated capacity of the energy storage device can be shown in the following table:

Energy storage capacity/L Rated capacity/kW 150 2.8 200 3.6

In other embodiments, the preset condition may also include that the rated capacity of the energy storage device is greater than the rated capacity of the outdoor unit.

Step S213: when the temperature of the energy storage medium is greater than the preset temperature and the capacity of the energy storage device does not meet the preset condition, determining the third defrost mode as the target defrost mode.

In one embodiment, when the temperature of the energy storage medium is less than or equal to the preset temperature, it indicates that the temperature of the energy storage medium is insufficient and cannot provide the required heat for defrosting the outdoor unit. At this time, the heat pump system defrosts in the second defrost mode to ensure the defrosting effect of the heat pump system and shorten the defrosting time to ensure that the heat pump system can quickly recover to the operating state actually required by the user after defrosting. When the temperature of the energy storage medium is greater than the preset temperature, it indicates that the temperature of the energy storage medium is high enough. At this time, it is further combined with whether the capacity of the energy storage device meets the preset conditions to distinguish whether the defrosting capacity of the energy storage device is sufficient to melt all the frost of the outdoor unit. If the capacity meets the preset conditions, it indicates that the defrosting capacity is large enough. At this time, the first defrosting mode is used for defrosting, and the indoor heat exchanger does not need to operate in the evaporation state, which is conducive to avoiding a significant drop in the indoor ambient temperature, so as to ensure the defrosting effect and improve the indoor comfort; if the capacity does not meet the preset conditions, it indicates that there is defrosting capacity but the defrosting capacity is insufficient. At this time, the third defrosting mode is used for defrosting, and the defrosting capacity is supplemented by evaporation of the indoor heat exchanger, which can reduce the drop in indoor temperature when the indoor heat exchanger is used alone to absorb heat for defrosting, thereby ensuring the defrosting effect and improving the indoor comfort.

In other embodiments, the first preset temperature is lower than the second preset temperature, and when the temperature of the energy storage medium is lower than or equal to the first preset temperature, the second defrost mode is determined to be the target defrost mode; when the temperature of the energy storage medium is higher than the second preset temperature, the first defrost mode is determined to be the target defrost mode; when the temperature of the energy storage medium is higher than the first preset temperature and lower than or equal to the second preset temperature, the third defrost mode is determined to be the target defrost mode. Alternatively, when the capacity of the energy storage device meets the preset conditions, the first defrost mode is determined to be the target defrost mode; when the capacity of the energy storage device does not meet the preset conditions, the second defrost mode or the third defrost mode is determined to be the target defrost mode.

In other embodiments, when the temperature of the energy storage medium is greater than the preset temperature, the first defrost mode is determined to be the target defrost mode.

In other embodiments, when the temperature and/or capacity state of the energy storage medium satisfies any of the mentioned conditions, other defrost modes different from the above-mentioned defrost modes may also be selected.

In one embodiment, the first status information also includes whether the heat pump system is installed with the energy storage device, and the step of determining the target defrost mode of the heat pump system according to the first status information includes: when the heat pump system has installed the energy storage device, determining the target defrost mode of the heat pump system according to the energy storage medium temperature and/or the capacity status; when the heat pump system is not installed with the energy storage device, determining the second defrost mode as the target defrost mode.

Based on this, when the energy storage device is not installed in the heat pump system due to damage, maintenance, etc., the defrosting effect of the heat pump system can be guaranteed and the normal heat exchange requirements of the heat pump system can be met.

Further, based on any of the above embodiments, another embodiment of the control method of the heat pump system of the present application is proposed. In one embodiment, the first state information includes the heat exchange state of the energy storage device, and the second state information includes the heat exchange state of the indoor heat exchanger. The heat exchange state of the energy storage device may include one of the following states: the energy storage device is in a condensing state, the energy storage device is in an evaporating state, the energy storage device is not in a heat exchange state, and so on. The heat exchange state of the indoor heat exchanger may include one of the following states: the indoor heat exchanger is in a condensing state, the indoor heat exchanger is in an evaporating state, the indoor heat exchanger is not in a heat exchange state, and so on. Here, the refrigerant pipe in the energy storage device is connected to the energy storage medium for heat exchange. When the refrigerant pipe in the energy storage device is in an evaporating state, the refrigerant flowing through can absorb the heat stored in the energy storage medium. When the refrigerant pipe in the energy storage device is in a condensing state, the energy storage medium can absorb the heat flowing through the refrigerant and store it. Referring to Figure 11, step S20 includes:

Step S22, when the indoor heat exchanger is in a condensing state and the refrigerant pipe in the energy storage device is not in a condensing state, determining that the second defrost mode is the target defrost mode;

When the heat pump system operates in the above-mentioned heating mode, the indoor heat exchanger is in a condensing state and the refrigerant pipe in the energy storage device is not in a condensing state.

Step S23, when the refrigerant pipes in the indoor heat exchanger and the energy storage device are both in a condensing state, or when the indoor heat exchanger is not in a condensing state and the refrigerant pipes in the energy storage device are in a condensing state, determine that the first defrost mode or the third defrost mode is the target defrost mode.

When the heat pump system operates in the above-mentioned heating and heat storage modes, the refrigerant pipes in the indoor heat exchanger and the energy storage device are both in a condensing state.

When the heat pump system operates in the above-mentioned heat storage mode, the indoor heat exchanger is not in a condensing state and the refrigerant pipe in the energy storage device is in a condensing state.

When the indoor heat exchanger and the refrigerant pipe in the energy storage device are both in a condensing state, or when the indoor heat exchanger is not in a condensing state and the refrigerant pipe in the energy storage device is in a condensing state, the target defrost mode can be determined in the first defrost mode and the third defrost mode according to the energy storage medium temperature and/or the capacity state. For example, when the capacity of the energy storage device meets the preset conditions required for the above-mentioned outdoor unit defrosting, the first defrost mode is determined to be the target defrost mode; when the capacity of the energy storage device does not meet the preset conditions, the third defrost mode is determined to be the target defrost mode. For another example, when the energy storage medium temperature of the energy storage device is greater than the preset medium temperature, the first defrost mode is determined to be the target defrost mode; when the energy storage medium temperature of the energy storage device is less than or equal to the preset medium temperature, the third defrost mode is determined to be the target defrost mode. For another example, when the energy storage medium temperature of the energy storage device is greater than the preset medium temperature and the capacity meets the preset conditions required for the above-mentioned outdoor unit defrosting, the first defrost mode is determined to be the target defrost mode; when the energy storage medium temperature of the energy storage device is less than or equal to the preset medium temperature, or when the capacity of the energy storage device does not meet the preset conditions, the third defrost mode is determined to be the target defrost mode.

In one embodiment, the heat exchange state of the energy storage device and the heat exchange state of the indoor heat exchanger can reflect whether the indoor heat exchanger and the energy storage device can provide heat for defrosting the outdoor unit after switching to the evaporation state. Based on this, the defrost mode is selected in combination with the heat exchange state of the energy storage device and the heat exchange state of the indoor heat exchanger, which is conducive to further ensuring the defrost effect, meeting the user's heat exchange needs and improving indoor comfort.

In other embodiments, when the indoor heat exchanger is in a condensing state and the refrigerant pipe in the energy storage device is not in a condensing state, the second defrost mode may be determined as the target defrost mode; when the refrigerant pipe in the energy storage device is in a condensing state, the first defrost mode may be determined as the target defrost mode.

Further, based on any of the above embodiments, another embodiment of the control method of the heat pump system of the present application is proposed. In one embodiment, the heat pump system includes a refrigerant main circuit and a refrigerant branch connected to the refrigerant main circuit, the refrigerant branch includes an energy storage device and a first control valve, the refrigerant main circuit includes a compressor, an indoor unit, an outdoor heat exchanger, a throttling device and a reversing component, the indoor unit includes the indoor heat exchanger and the second control valve, the indoor unit, the second control valve, the throttling device and the outdoor heat exchanger are connected in sequence, the pipeline between the indoor unit and the throttling device is connected to one end of the refrigerant branch, the other end of the refrigerant branch, the indoor unit, the outdoor heat exchanger, the exhaust port of the compressor and the return air port of the compressor are all connected to the reversing component, and step S30 includes:

When the heat pump system operates in the first defrost mode, the reversing assembly is controlled to operate so that the exhaust port of the compressor is connected to the outdoor heat exchanger, the refrigerant branch and the indoor unit are connected to the return air port of the compressor, the first control valve is controlled to be opened, and the second control valve is controlled to be closed;

When the heat pump system operates in the second defrost mode, the reversing assembly is controlled to operate so that the exhaust port of the compressor is connected to the outdoor heat exchanger, the refrigerant branch and the indoor unit are connected to the return air port of the compressor, the first control valve is controlled to be closed, and the second control valve is controlled to be opened;

When the heat pump system runs the third defrost mode, the reversing component is controlled to operate so that the exhaust port of the compressor is connected to the outdoor heat exchanger, the refrigerant branch and the indoor unit are connected to the return air port of the compressor, and the first control valve and the second control valve are controlled to be open.

In one embodiment, the reversing assembly includes a first reversing valve, a second reversing valve and a switching valve, the exhaust port, the return air port and the indoor heat exchanger are all connected to the first reversing valve, the exhaust port, the return air port and the outdoor heat exchanger are all connected to the second reversing valve, the exhaust port, the return air port and the refrigerant branch are all connected to the switching valve, and the step of controlling the reversing assembly to operate so that the exhaust port of the compressor is connected to the outdoor heat exchanger, the refrigerant branch and the indoor unit are all connected to the return air port of the compressor includes: controlling the first reversing valve to operate in a first valve position so that the return air port is connected to the indoor unit, controlling the second reversing valve to operate in a third valve position so that the exhaust port is connected to the outdoor heat exchanger, and controlling the switching valve to operate in a first switching state so that the return air port is connected to the refrigerant branch.

Based on this, the operating status of the heat pump system in each defrost mode is as follows:

In the first defrost mode, referring to FIG. 4 , the first reversing valve operates at the first valve position, the second reversing valve operates at the third valve position, the switching valve is in the first switching state, the first control valve is opened, and the second control valve is closed. The exhaust port of the compressor is connected to the outdoor heat exchanger, and the refrigerant discharged from the compressor flows through the outdoor heat exchanger and the throttling device in sequence and then all flows into the refrigerant branch. The refrigerant flowing into the refrigerant branch is in an evaporating state when flowing through the energy storage device and absorbs heat from the energy storage medium in the energy storage device. The refrigerant flowing out of the refrigerant branch flows back to the compressor. In the first defrost mode, the outdoor heat exchanger is in a condensing state to release heat to melt the frost in the outdoor unit, and the refrigerant pipeline in the energy storage device is in an evaporating state to absorb heat for defrosting the outdoor unit.

In the second defrost mode, referring to FIG. 5 , the first reversing valve operates at the first valve position, the second reversing valve operates at the third valve position, the switching valve is in the first switching state, the first control valve is opened, and the second control valve is closed, the exhaust port of the compressor is connected to the outdoor heat exchanger, and the refrigerant discharged from the compressor flows through the outdoor heat exchanger and the throttling device in sequence and then flows into the indoor unit. The refrigerant flowing into the indoor unit absorbs the heat in the indoor environment and then flows back to the compressor. In the second defrost mode, the outdoor heat exchanger is in a condensing state to release heat to melt the frost in the outdoor unit, and the indoor heat exchanger is in an evaporating state to absorb heat for defrosting the outdoor unit.

In the third defrost mode, referring to FIG. 6 , the first reversing valve operates at the first valve position, the second reversing valve operates at the third valve position, the switching valve is in the first switching state, the first control valve is opened, and the second control valve is closed. The exhaust port of the compressor is connected to the outdoor heat exchanger, and the refrigerant discharged from the compressor flows through the outdoor heat exchanger and the throttling device in sequence and then flows into the indoor unit and the refrigerant branch respectively. The refrigerant flowing into the refrigerant branch is in an evaporating state when flowing through the energy storage device and absorbs heat from the energy storage medium in the energy storage device, and the refrigerant flowing into the indoor unit is in an evaporating state to absorb heat from the indoor environment, and the refrigerant flowing out of the indoor unit and the refrigerant branch flows back to the compressor. In the third defrost mode, the outdoor heat exchanger is in a condensing state to release heat to melt the frost in the outdoor unit, while the indoor heat exchanger and the energy storage device can absorb heat for defrosting the outdoor unit.

In one embodiment, through the above-mentioned method, the heat pump system can adapt to the actual working conditions and select a suitable defrost mode from the three defrost modes for defrosting, thereby ensuring the defrost effect while improving indoor comfort.

In other embodiments, the first reversing valve and the second reversing valve may also be replaced by a third four-way valve, and the exhaust port of the compressor, the return air port of the compressor, the indoor heat exchanger, and the outdoor heat exchanger are respectively connected to different valve ports of the third four-way valve. The third four-way valve has a fifth valve position and a sixth valve position, and the fifth valve position corresponds to the return air port being connected to the indoor unit, and the exhaust port being connected to the outdoor heat exchanger; the sixth valve position corresponds to the return air port being connected to the outdoor heat exchanger, and the exhaust port being connected to the indoor unit. The step of controlling the reversing assembly to operate so that the exhaust port of the compressor is connected to the outdoor heat exchanger, and the refrigerant branch and the indoor unit are both connected to the return air port of the compressor includes: controlling the third four-way valve to operate in the fifth valve position so that the return air port is connected to the indoor unit, and the exhaust port is connected to the outdoor heat exchanger.

In addition, an embodiment of the present application further proposes a storage medium, on which a control program of a heat pump system is stored. When the control program of the heat pump system is executed by a processor, the relevant steps of any embodiment of the control method of the heat pump system are implemented.

It should be noted that, in this article, the terms "include", "comprises" or any other variations thereof are intended to cover non-exclusive inclusion, so that a process, method, article or system including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or system. In the absence of further restrictions, an element defined by the sentence "comprises a ..." does not exclude the existence of other identical elements in the process, method, article or system including the element.

The serial numbers of the above-mentioned embodiments of the present application are for description only and do not represent the advantages or disadvantages of the embodiments.

Through the description of the above implementation methods, those skilled in the art can clearly understand that the above-mentioned embodiment methods can be implemented by means of software plus a necessary general hardware platform, and of course by hardware, but in many cases the former is a better implementation method. Based on such an understanding, the technical solution of the present application is essentially or the part that contributes to the prior art can be embodied in the form of a software product, which is stored in a storage medium (such as ROM/RAM, magnetic disk, optical disk) as described above, and includes a number of instructions for a terminal device (which can be a mobile phone, computer, server, heat pump system, or network device, etc.) to execute the methods described in each embodiment of the present application.

The above are only optional embodiments of the present application, and are not intended to limit the patent scope of the present application. Any equivalent structure or equivalent process transformation made using the contents of the present application specification and drawings, or directly or indirectly applied in other related technical fields, are also included in the patent protection scope of the present application.

Claims (11)

A control method for a heat pump system, wherein the heat pump system has at least two of a first defrost mode, a second defrost mode, and a third defrost mode, wherein in the first defrost mode, a refrigerant pipe in an energy storage device of the heat pump system is in an evaporating state, in the second defrost mode, an indoor heat exchanger of the heat pump system is in an evaporating state, and in the third defrost mode, both the refrigerant pipe in the energy storage device and the indoor heat exchanger are in an evaporating state, and the control method for the heat pump system comprises the following steps: When the heat pump system runs to meet the defrosting condition, obtaining first state information of the energy storage device in the heat pump system and/or second state information of the indoor heat exchanger; determining a target defrost mode of the heat pump system according to the first state information and/or the second state information; The heat pump system is controlled to run the target defrost mode to defrost an outdoor unit of the heat pump system. The control method of the heat pump system according to claim 1, wherein the first state information includes the energy storage medium temperature of the energy storage device and/or the capacity state of the energy storage device, and the step of determining the target defrosting mode of the heat pump system according to the first state information includes: A target defrosting mode of the heat pump system is determined according to the energy storage medium temperature and/or the capacity state. The control method of the heat pump system according to claim 2, wherein the step of determining the target defrosting mode of the heat pump system according to the energy storage medium temperature and/or the capacity state comprises: When the temperature of the energy storage medium is less than or equal to a preset temperature, determining the second defrost mode as the target defrost mode; and/or When the temperature of the energy storage medium is greater than the preset temperature, determining the first defrost mode as the target defrost mode; and/or When the temperature of the energy storage medium is greater than the preset temperature and the capacity of the energy storage device meets the preset conditions required for defrosting of the outdoor unit, determining the first defrost mode as the target defrost mode; and/or When the temperature of the energy storage medium is greater than the preset temperature and the capacity of the energy storage device does not meet the preset condition, the third defrost mode is determined to be the target defrost mode. The control method of the heat pump system according to claim 3, wherein the preset condition includes: a ratio of the rated capacity of the energy storage device to the rated capacity of the outdoor unit is greater than or equal to a preset value. The control method of the heat pump system according to claim 4, wherein the rated capacity of the energy storage device is positively correlated with the energy storage volume of the energy storage device. The control method of the heat pump system according to claim 2, wherein the first state information further includes whether the heat pump system is installed with the energy storage device, and the step of determining the target defrosting mode of the heat pump system according to the first state information includes: When the heat pump system has been installed with the energy storage device, determining a target defrosting mode of the heat pump system according to the temperature of the energy storage medium and/or the capacity state; When the heat pump system is not equipped with the energy storage device, the second defrost mode is determined to be the target defrost mode. The control method of the heat pump system according to claim 1, wherein the first state information includes the heat exchange state of the energy storage device, the second state information includes the heat exchange state of the indoor heat exchanger, and the step of determining the target defrosting mode of the heat pump system according to the first state information and the second state information comprises: When the indoor heat exchanger is in a condensing state and the refrigerant pipe in the energy storage device is not in a condensing state, determining that the second defrosting mode is the target defrosting mode; When the refrigerant pipes in the indoor heat exchanger and the energy storage device are both in a condensing state, or when the indoor heat exchanger is not in a condensing state and the refrigerant pipes in the energy storage device are in a condensing state, the first defrost mode or the third defrost mode is determined as the target defrost mode. The control method of a heat pump system according to any one of claims 1 to 7, wherein the heat pump system comprises a refrigerant main circuit and a refrigerant branch circuit connected to the refrigerant main circuit, the refrigerant branch circuit comprises an energy storage device and a first control valve, the refrigerant main circuit comprises a compressor, an indoor unit, an outdoor heat exchanger, a throttling device and a reversing component, the indoor unit comprises the indoor heat exchanger and a second control valve, the indoor unit, the second control valve, the throttling device and the outdoor heat exchanger are connected in sequence, a pipeline between the indoor unit and the throttling device is connected to one end of the refrigerant branch circuit, the other end of the refrigerant branch circuit, the indoor unit, the outdoor heat exchanger, the exhaust port of the compressor and the return air port of the compressor are all connected to the reversing component, and the step of controlling the heat pump system to operate the target defrost mode to defrost the outdoor unit of the heat pump system comprises: When the heat pump system operates in the first defrost mode, the reversing assembly is controlled to operate so that the exhaust port is connected to the outdoor heat exchanger, the refrigerant branch and the indoor unit are both connected to the return air port, the first control valve is controlled to be opened, and the second control valve is controlled to be closed; When the heat pump system operates in the second defrost mode, the reversing assembly is controlled to operate so that the exhaust port is connected to the outdoor heat exchanger, the refrigerant branch and the indoor unit are both connected to the return air port, the first control valve is controlled to be closed, and the second control valve is controlled to be opened; When the heat pump system runs the third defrost mode, the reversing component is controlled to operate so that the exhaust port is connected to the outdoor heat exchanger, the refrigerant branch and the indoor unit are connected to the return air port, and the first control valve and the second control valve are controlled to be open. The control method of the heat pump system according to claim 8, wherein the reversing component includes a first reversing valve, a second reversing valve and a switching valve, the exhaust port, the return air port and the indoor heat exchanger are all connected to the first reversing valve, the exhaust port, the return air port and the outdoor heat exchanger are all connected to the second reversing valve, the exhaust port, the return air port and the refrigerant branch are all connected to the switching valve, and the step of controlling the reversing component to operate so that the exhaust port is connected to the outdoor heat exchanger, and the refrigerant branch and the indoor unit are all connected to the return air port comprises: The first reversing valve is controlled to operate in a first valve position so that the return air port is connected to the indoor unit, the second reversing valve is controlled to operate in a third valve position so that the exhaust port is connected to the outdoor heat exchanger, and the switching valve is controlled to operate in a first switching state so that the return air port is connected to the refrigerant branch. A heat pump system, wherein the heat pump system comprises: a memory, a processor, and a control program of the heat pump system stored in the memory and executable on the processor, wherein the control program of the heat pump system, when executed by the processor, implements the steps of the control method of the heat pump system as described in any one of claims 1 to 9. A storage medium, wherein a control program of a heat pump system is stored on the storage medium, and when the control program of the heat pump system is executed by a processor, the steps of the control method of the heat pump system as described in any one of claims 1 to 9 are implemented.