Patent Application
20230384001
This application claims priority to Chinese Patent Application No. 202210568369.7 filed on May 24, 2022.
The present invention relates to the field of heat pumps, in particular to a heat pump system and a control method thereof.
In order to improve the comfort of air-conditioning systems, the common air-conditioning systems have a heating mode. The air-conditioning systems with a cooling mode and a heating mode are also referred to as heat pump systems. In order to improve the heat pump system's capacity in the heating mode, an Enhanced Vapor Injection (EVI) compressor and an economizer located in front of a throttling device are often used, which can increase the system's heating capacity by about 10%.
In order to enable the EVI compressor and the economizer to also function in the cooling mode, i.e., to improve the system's capacity in the cooling mode, a complex pipeline structure with four check valves and one expansion valve is usually used, which challenges the reliability of the check valves.
According to a first aspect, a heat pump system is provided, comprising:
a compressor having a compressor inlet and a compressor outlet;
a change-over valve configured to selectively connect the compressor inlet and the compressor outlet to a first flow path and a second flow path;
a heat-source-side heat exchanger on the first flow path;
a user-side heat exchanger on the second flow path;
a first branch and a second branch between the first flow path and the second flow path, the first branch being provided with a three-way valve, and the second branch being provided with a first throttling device and a second throttling device, wherein the three-way valve has a first port and a second port for communicating with the first flow path and a third port for communicating with the second flow path; and
a third branch connected between a first position between the first throttling device and the second throttling device and the second port of the three-way valve, where an economizer is provided on the third branch.
Optionally, in an embodiment of the heat pump system, the compressor is an EVI compressor, the EVI compressor further comprises an air supply port, and the economizer comprises a port connected to the air supply port.
Optionally, in an embodiment of the heat pump system, the three-way valve is configured to only allow refrigerant to flow from its first port to its second port in a cooling mode, and to only allow refrigerant to flow from its third port to its second port in a heating mode.
Optionally, in an embodiment of the heat pump system, the first throttling device and the second throttling device are expansion valves.
Optionally, in an embodiment of the heat pump system, the heat pump system further comprises a controller for controlling the first throttling device and the second throttling device, wherein the controller is configured to turn off the first throttling device and allow the second throttling device to throttle in the cooling mode, and to turn off the second throttling device and allow the first throttling device to throttle in the heating mode.
Optionally, in an embodiment of the heat pump system, the three-way valve is a three-way stop valve, and the controller is configured to control the three-way valve such that the first and second ports of the three-way valve are turned on and the third port is turned off in the cooling mode, and the third and second ports of the three-way valve are turned on and the first port is turned off in the heating mode.
According to a second aspect, a control method of a heat pump system is provided, which is for use in a heat pump system according to the various embodiments, the method comprising: turning off the first throttling device and allowing the second throttling device to throttle in a cooling mode such that refrigerant passes through the first port of the three-way valve, the second port of the three-way valve, the economizer and the second throttling device in turn, and turning off the second throttling device and allowing the first throttling device to throttle in a heating mode such that refrigerant passes through the third port of the three-way valve, the second port of the three-way valve, the economizer and the first throttling device in turn.
According to a third aspect, a heat pump system is provided, comprising:
a compressor having a compressor inlet and a compressor outlet;
a change-over valve configured to selectively connect the compressor inlet and the compressor outlet to a first flow path and a second flow path;
a heat-source-side heat exchanger on the first flow path;
a user-side heat exchanger on the second flow path;
a first three-way valve and a second three-way valve arranged in parallel between the first flow path and the second flow path, wherein the first three-way valve has a first port and a second port for communicating with the first flow path and a third port for connecting with the second flow path, and the second three-way valve has a first port and a second port for communicating with the first flow path and a third port for connecting with the second flow path; and
an economizer and a throttling device connected in turn between the second port of the first three-way valve and the second port of the second three-way valve.
Optionally, in an embodiment of the heat pump system, the compressor is an EVI compressor, the EVI compressor further comprises an air supply port, and the economizer comprises a port connected to the air supply port.
Optionally, in an embodiment of the heat pump system, the first three-way valve is configured to only allow refrigerant to flow from its first port to its second port in a cooling mode and to only allow refrigerant to flow from its third port to its second port in a heating mode; the second three-way valves is configured to only allow refrigerant to flow from its second port to its third port in the cooling mode and to only allow refrigerant to flow from its second port to its first port in the heating mode.
Optionally, in an embodiment of the heat pump system, the throttling device is an expansion valve.
Optionally, in an embodiment of the heat pump system, the first three-way valve is a first three-way stop valve and the second three-way valve is a second three-way stop valve, wherein the heat pump system further comprises a controller for controlling the first three-way valve and the second three-way valve, such that the first and second ports of the first three-way valve are turned on and the third port of the first three-way valve is turned off, and the second and third ports of the second three-way valve are turned on and the first port of the second three-way valve is turned off in the cooling mode; and the second and third ports of the first three-way valve are turned on and the first port of the first three-way valve is turned off, and the first and second ports of the second three-way valve are turned on and the third port of the second three-way valve is turned off in the heating mode.
According to a fourth aspect, a control method of a heat pump system is provided, which is for use in a heat pump system according to the various embodiments, the method comprising:
turning on the first and second ports of the first three-way valve and turning off the third port of the first three-way valve, and turning on the second and third ports of the second three-way valve and turning off the first port of the second three-way valve in the cooling mode, such that refrigerant passes through the first port of the first three-way valve, the second port of the first three-way valve, the economizer, the throttling device, the second port of the second three-way valve and the third port of the second three-way valve in turn; and
turning on the second and third ports of the first three-way valve and turning off the first port of the first three-way valve, and turning on the first and second ports of the second three-way valve and turning off the third port of the second three-way valve in the heating mode, such that refrigerant passes through the third port of the first three-way valve, the second port of the first three-way valve, the economizer, the throttling device, the second port of the second three-way valve and the first port of the second three-way valve in turn.
According to a fifth aspect, a heat pump system is provided, comprising:
a compressor having a compressor inlet and a compressor outlet;
a change-over valve configured to selectively connect the compressor inlet and the compressor outlet to a first flow path and a second flow path;
a heat-source-side heat exchanger on the first flow path;
a user-side heat exchanger on the second flow path;
a four-way valve arranged between the first flow path and the second flow path, wherein the four-way valve has a first port and a second port for communicating with the first flow path, and a third port and a fourth port for communicating with the second flow path; and
an economizer and a throttling device connected in turn between the second port and the fourth port of the four-way valve.
Optionally, in an embodiment of the heat pump system, the compressor is an EVI compressor, the EVI compressor further comprises an air supply port, and the economizer comprises a port connected to the air supply port.
Optionally, in an embodiment of the heat pump system, the four-way valve is configured to only allow refrigerant to flow from its first port to its second port, and from its fourth port to its third port in the cooling mode, and to only allow refrigerant to flow from its third port to its second port, and from its fourth port to its first port in the heating mode.
Optionally, in an embodiment of the heat pump system, the throttling device is an expansion valve.
Optionally, in an embodiment of the heat pump system, the four-way valve is a four-way stop valve, and the heat pump system further comprises a controller for controlling the four-way valve, such that the first and second ports of the four-way valve are communicated and the third and fourth ports of the four-way valve are communicated in the cooling mode, and the first and fourth ports of the four-way valve are communicated and the second and third ports of the four-way valve are communicated in the heating mode.
According to a sixth aspect, a control method of a heat pump system is provided, which is for use in a heat pump system according to the various embodiments, the method comprising:
communicating the first and second ports of the four-way valve and communicating the third and fourth ports of the four-way valve in a cooling mode, such that refrigerant passes through the first port of the four-way valve, the second port of the four-way valve, the economizer, the throttling device, the fourth port of the four-way valve and the third port of the four-way valve in turn; and
communicating the first and fourth ports of the four-way valve and communicating the second and third ports of the four-way valve in a heating mode, such that refrigerant passes through the third port of the four-way valve, the second port of the four-way valve, the economizer, the throttling device, the fourth port of the four-way valve and the first port of the four-way valve in turn.
A heat pump system and a control method thereof according to the embodiments of the present invention can be used in both cooling and heating modes. In addition, the use of multiple-way valves can improve the reliability of the heat pump system.
With reference to the accompanying drawings, the disclosure of the present application will become easier to understand. Those skilled in the art would readily appreciate that these drawings are for the purpose of illustration, and are not intended to limit the protection scope of the present application. In addition, in the figures, similar numerals are used to denote similar components, where:
In conjunction with other alternative embodiments in the above embodiments, the application of combining a heat pump system according to the embodiments of the present invention with an EVI compressor may be considered. The compressor is an Enhanced Vapor Injection (EVI) compressor, which includes not only the compressor inlet and the compressor outlet, but also an air supply port (not shown). The compressor is connected with the heat pump system part shown in
In some embodiments, the three-way valve 150 is configured to only allow refrigerant to flow from its first port 151 to its second port 152 in the cooling mode (as shown in
The heat pump system according to the embodiments of the present invention employs a three-way valve and two electronic expansion valves to realize the application of an economizer in the cooling and heating modes. Compared to the existing structure with four check valves and a single expansion valve, the number of valves is reduced, in particular the number of check valves with poor stability, which improves system stability.
According to another aspect, the embodiments of the present invention also provide a control method of a heat pump system, the method comprising: turning off the first throttling device 141 and allowing the second throttling device 142 to throttle in the cooling mode, such that refrigerant passes through the first port 151 of the three-way valve 150, the second port 152 of the three-way valve 150, the economizer 170 and the second throttling device 142 in turn, as shown by the arrows in
In conjunction with other alternative embodiments of the above embodiments, the application of combining a heat pump system according to the embodiments of the present invention with an EVI compressor may be considered. The compressor is an Enhanced Vapor Injection (EVI) compressor, which includes not only the compressor inlet and the compressor outlet, but also an air supply port (not shown). The compressor is connected with the heat pump system part shown in
In some embodiments, the first three-way valve 230 is configured to only allow refrigerant to flow from its first port 231 to its second port 232 in the cooling mode (as shown in
The heat pump system according to the embodiments of the present invention employs three-way valves arranged in parallel and an electronic expansion valve to realize the application of an economizer in the cooling and heating modes. Compared to the existing structure with four check valves and a single expansion valve, the number of valves is reduced, in particular the number of check valves with poor stability, which improves system stability.
According to another aspect, the embodiments of the present invention also provide a control method of a heat pump system, the method comprising: turning on the first port 231 and the second port 232 of the first three-way valve 230 and turning off the third port 233 of the first three-way valve 230, and turning on the second port 242 and the third port 243 of the second three-way valve 240 and turning off the first port 241 of the second three-way valve 240 in the cooling mode, such that refrigerant passes through the first port 231 of the first three-way valve 230, the second port 232 of the first three-way valve 230, the economizer 250, the throttling device 260, the second port 242 of the second three-way valve 240 and the third port 243 of the second three-way valve 240 in turn, as shown by the arrows in
In conjunction with other alternative embodiments of the above embodiments, the application of combining a heat pump system according to the embodiments of the present invention with an EVI compressor may be considered. The compressor is an Enhanced Vapor Injection (EVI) compressor, which includes not only the compressor inlet and the compressor outlet, but also an air supply port (not shown). The compressor is connected with the heat pump system part shown in
In some embodiments, the four-way valve 330 is configured to only allow refrigerant to flow from its first port 331 to its second port 332 and from its fourth port 334 to its third port 333 in the cooling mode (as shown in
The heat pump system according to the embodiments of the present invention employs a four-way valve and an electronic expansion valve to realize the application of an economizer in the cooling and heating modes. Compared to existing structure with four check valves and a single expansion valve, the number of valves is reduced, in particular the number of check valves with poor stability, which improves system stability.
According to another aspect, embodiments of the present invention also provide a control method of a heat pump system, the method comprising: communicating the first port 331 and the second port 332 of the four-way valve 330, and communicating the third port 333 and the fourth port 334 of the four-way valve 330 in the cooling mode, such that refrigerant passes through the first port 331 of the four-way valve 330, the second port 332 of the four-way valve 330, the economizer 340, the throttling device 350, the fourth port 334 of the four-way valve 330, and the third port 333 of the four-way valve 330 in turn, as shown by the arrows in
The specific embodiments of the present invention described above are merely for a clearer description of the principles of the present invention, in which individual components are clearly shown or described to make the principles of the present invention easier to understand. Various modifications or changes to the present application may be easily made by those skilled in the art without departing from the scope of the present application. It should therefore be understood that these modifications or changes shall be included within the scope of the patent protection of the present application.
| Number | Date | Country | Kind |
|---|---|---|---|
| 202210568369.7 | May 2022 | CN | national |
