Patent Application
20230296295
This application claims priority to Chinese Patent Application No. 202210268739.5, filed Mar. 18, 2022, and all the benefits accruing therefrom under 35 U.S.C. ยง 119, the contents of which in its entirety are herein incorporated by reference.
The present invention relates to the field of heat pumps, in particular to a heat pump system with an economizer capable of operating in both cooling and heating modes.
In order to improve the comfort of air conditioning systems, common air conditioning systems have the heating mode. Air conditioning systems with both cooling and heating modes are also referred to as heat pump systems. In order to improve the capacity of the heat pump system in the heating mode, the Enhanced Vapor Injection (EVI) compressor and the economizer located in front of the throttling device are often used. This structure can increase the heating capacity of the system by about 10%.
In order to enable the EVI compressor and the economizer to also operate in the cooling mode, i.e., to improve the capacity of the system in the cooling mode, it is usually necessary to employ a complicated pipeline structure with four check valves and one expansion valve, which challenges the reliability of the check valves.
The object of the present application is to solve or at least alleviate the problems existing in the prior art.
According to one aspect, a heat pump system is provided, which comprises: a compressor having a compressor inlet and a compressor outlet; a reversing 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, wherein the first branch is provided with a first valve and a second valve, and the second branch is provided with a first throttling device and a second throttling device; and an economizer connected between a first position between the first valve and the second valve on the first branch and a second position between the first throttling device and the second throttling device on the second branch.
Optionally, in an embodiment of the heat pump system, the compressor is an EVI compressor, wherein the EVI compressor further comprises an air supplement port, and the economizer comprises a port connected with the air supplement port.
Optionally, in an embodiment of the heat pump system, the economizer is a flash tank, wherein the inlet of the flash tank is connected to the first position, the gas-phase outlet of the flash tank is connected to the air supplement port, and the liquid-phase outlet of the flash tank is connected to the second position.
Optionally, in an embodiment of the heat pump system, the economizer is a heat exchanger comprising a first pipeline and a second pipeline. The first pipeline is connected between the first position and the second position, and a branch path is branched out at a third position between the first position or the second position and the economizer, wherein the branch path is provided with an additional throttling device, and is connected to the air supplement port of the compressor through the second pipeline of the economizer.
Optionally, in an embodiment of the heat pump system, the first valve is a check valve that only allows refrigerant fluid to flow from the first flow path to the first position, and the second valve is a check valve that only allows refrigerant fluid to flow from the second flow path to the first position.
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 that controls the first throttling device and the second throttling device. The controller is configured to turn off the first throttling device and allow the second throttling device to play a throttling role in a cooling mode, and turn off the second throttling device and allow the first throttling device to play a throttling role in a heating mode.
Optionally, in an embodiment of the heat pump system, the first valve and the second valve are cut-off valves. The controller is configured to control the first valve and the second valve, so that the first valve is turned on and the second valve is turned off in the cooling mode, and the second valve is turned on and the first valve is turned off in the heating mode.
According to another aspect, a control method of a heat pump system is provided, which is for use in the heat pump system according to the various embodiments. The method comprises: turning off the first throttling device and allowing the second throttling device to play a throttling role in the cooling mode, so that the refrigerant passes through the first valve, the economizer and the second throttling device in turn; and turning off the second throttling device and allowing the first throttling device to play a throttling role in the heating mode, so that the refrigerant passes through the second valve, the economizer and the first throttling device in turn.
Optionally, the method further comprises: using a flash tank as an economizer, so that after the refrigerant enters the flash tank, gas-phase refrigerant is delivered to the air supplement port of the compressor, and liquid-phase refrigerant is delivered to the first throttling device or the second throttling device; or using a heat exchanger comprising a first pipeline and a second pipeline as the economizer, and dividing the refrigerant into a first part and a second part before it enters the first pipeline or after it leaves the first pipeline, wherein the first part of the refrigerant is delivered to the first throttling device or the second throttling device, and the second part of the refrigerant is delivered to the air supplement port of the compressor after passing through an additional throttling device and then through the second pipeline of the economizer.
The system and method according to the embodiments of the present invention improves the system capacity using the economizer in the cooling and heating modes, and has stronger reliability.
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:
With continued reference to
In some embodiments, the first valve 72 is a check valve that only allows refrigerant fluid to flow from the first flow path 31 to the first position 621, and the second valve 71 is a check valve that only allows refrigerant fluid to flow from the second flow path 32 to the first position 621. In some embodiments, the first throttling device 82 and the second throttling device 81 are both expansion valves, such as electronic expansion valves. In some embodiments, the heat pump system also comprises a controller that controls the first throttling device 82 and the second throttling device 81. The controller is configured to turn off the first throttling device 82 and allow the second throttling device 81 to play a throttling role in the cooling mode, and to turn off the second throttling device 81 and allow the first throttling device 82 to play a throttling role in the heating mode. In some embodiments, the first valve 72 and the second valve 71 can also be cut-off valves. The controller is configured to control the first valve 72 and the second valve 71, so that the first valve 72 is turned on and the second valve 71 is turned off in the cooling mode, and the second valve 71 is turned on and the first valve 72 is turned off in the heating mode. In some embodiments, other suitable types of valves can also be utilized to achieve the above functions.
With continued reference to
In an alternative embodiment, as shown in
In this embodiment, in the cooling mode, the refrigerant leaving from the compressor outlet 11 enters from port a and leaves from port b of the reversing valve 2, enters the heat source-side heat exchanger 4 which serves as a condenser, and then passes through the first valve 72 (the first throttling device 82 is turned off). Then, at the third position 903, the refrigerant is divided into a first part that passes through the first pipeline 901 of the economizer and a second part that enters the second pipeline 902 of the economizer 900 after passing through the additional throttling device 904. After the first part and the second part of the refrigerant exchange heat in the economizer 900, the second part of the refrigerant returns to the air supplement port 13 of the compressor 1. The first part of the refrigerant passes through the second throttling device 81 for throttling, then passes through the user-side heat exchanger 5 which serves as an evaporator, passes through the second flow path 32, enters from the port c and leaves from port d of the reversing valve 2, and finally returns to the compressor inlet 12. In the heating mode, the refrigerant leaving from the compressor outlet 11 enters from the port a and leaves from port c of the reversing valve 2, enters the user-side heat exchanger 5 which serves as a condenser, and then passes through the second valve 71 (the second throttling device 81 is turned off). Then, at the third position 903, the refrigerant is divided into a first part that passes through the first pipeline 901 of the economizer and a second part that enters the second pipeline 902 of the economizer 900 after passing through the additional throttling device 904. After the first part and the second part of the refrigerant exchange heat in the economizer 900, the second part of the refrigerant returns to the air supplement port 13 of the compressor 1. The first part of the refrigerant passes through the first throttling device 82 for throttling, then passes through the heat source-side heat exchanger 4 which serves as an evaporator, passes through the first flow path 31, enters from the port b and leaves from port d of the reversing valve 2, and finally returns to the compressor inlet 12. It can be seen that in the heat pump system according to the embodiment in
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 and allowing the second throttling device to play a throttling role in the cooling mode, so that the refrigerant passes through the first valve, the economizer and the second throttling device in turn; and turning off the second throttling device and allowing the first throttling device to play a throttling role in the heating mode, so that the refrigerant passes through the second valve, the economizer and the first throttling device in turn.
In some embodiments, the method further comprises: using a flash tank as an economizer, so that after the refrigerant enters the flash tank, gas-phase refrigerant is delivered to the air supplement port of the compressor, and liquid-phase refrigerant is delivered to the first throttling device or the second throttling device; or using a heat exchanger comprising a first pipeline and a second pipeline as the economizer, and dividing the refrigerant into a first part and a second part before it enters the first pipeline or after it leaves the first pipeline, wherein the first part of the refrigerant is delivered to the first throttling device or the second throttling device, and the second part of the refrigerant is delivered to the air supplement port of the compressor after passing through an additional throttling device and then through the second pipeline of the economizer.
The specific embodiments of the present application described above are merely intended to describe the principles of the present application more clearly, wherein various components are clearly shown or described to facilitate the understanding of the principles of the present invention. Those skilled in the art may, without departing from the scope of the present application, make various modifications or changes to the present application. Therefore, it should be understood that these modifications or changes should be included within the scope of patent protection of the present application.
| Number | Date | Country | Kind |
|---|---|---|---|
| 202210268739.5 | Mar 2022 | CN | national |
