CN117847705A

CN117847705A - Defrosting control method of air conditioning system

Info

Publication number: CN117847705A
Application number: CN202211214200.8A
Authority: CN
Inventors: 邵宗臣; 董辰; 张恒
Original assignee: Qingdao Hisense Hitachi Air Conditioning System Co Ltd
Current assignee: Qingdao Hisense Hitachi Air Conditioning System Co Ltd
Priority date: 2022-09-30
Filing date: 2022-09-30
Publication date: 2024-04-09

Abstract

The invention discloses a defrosting control method of an air conditioning system, which relates to the technical field of air conditioners and can improve the comfort of users to a great extent. An air conditioning system includes: the compressor, first switching-over subassembly, the second switching-over subassembly, indoor heat exchanger, outdoor heat exchanger subassembly and defrosting branch road, first switching-over subassembly has first to fourth valve port, first valve port links to each other with the gas vent, the fourth valve port links to each other with the induction port, the second switching-over subassembly has first to third port, first port links to each other with the gas vent, the second port links to each other with the induction port, outdoor heat exchanger subassembly includes first part and second part, the first end of first part links to each other with the third valve port, the first end of second part links to each other with the third port, the first end of defrosting branch road links to each other with the gas vent, the second end of defrosting branch road links to each other with the second end of first part, the series connection has first on-off valve on the defrosting branch road. The air conditioning system of the present invention is used for air conditioning.

Description

Defrosting control method of air conditioning system

Technical Field

The invention relates to the technical field of air conditioners, in particular to a defrosting control method of an air conditioning system.

Background

When the air conditioning system performs heating operation, the outdoor heat exchanger component can frost after the temperature and the humidity of the external environment reach certain conditions. In the related art, an air conditioning system defrost an outdoor heat exchanger assembly in a reverse defrosting mode, and the refrigerant discharged from a compressor is supplied to the outdoor heat exchanger assembly by flowing the refrigerant in heating in a reverse direction, so that the outdoor heat exchanger assembly is defrosted by using heat of the compressor. When the air conditioning system is reversely defrosted, the indoor heating is stopped, and the indoor heat exchanger is required to absorb a part of heat from the indoor, so that the indoor temperature is reduced, the indoor thermal comfort is seriously affected, and the use experience of a user is reduced.

Disclosure of Invention

The embodiment of the invention provides a defrosting control method of an air conditioning system, which can greatly improve the comfort of users.

An embodiment of a first aspect of the present application provides a defrosting control method for an air conditioning system, the air conditioning system including: the first defrosting flow path comprises an exhaust port of the compressor, a defrosting branch, a first part of the outdoor heat exchanger and an air suction port of the compressor which are sequentially connected, and a first on-off valve is connected in series on the defrosting branch; the second defrosting flow path comprises an exhaust port, a second part of the outdoor heat exchanger, a second throttle valve, a first part of the outdoor heat exchanger and an air suction port of the compressor which are connected in sequence;

The defrosting control method comprises the following steps:

judging whether the air conditioning system meets a defrosting condition or not when the heating mode is operated;

if yes, controlling the air conditioning system to operate a first defrosting mode, and defrosting one of the first part and the second part in the first defrosting mode;

judging whether the air conditioning system meets a first defrosting mode ending condition;

if yes, controlling the air conditioning system to exit a first defrosting mode, and operating a second defrosting mode, wherein in the second defrosting mode, defrosting is carried out on the other one of the first part and the second part;

judging whether the air conditioning system meets a second defrosting mode ending condition;

if yes, controlling the air conditioning system to exit a second defrosting mode;

the first on-off valve is closed, high-temperature and high-pressure refrigerant gas discharged by the compressor flows through a first part of the outdoor unit, and a second part of the outdoor heat exchanger is used as an evaporator;

when defrosting the first part, the second throttle valve throttles, and the first on-off valve is opened; when defrosting the second part, the second throttle valve is fully opened, and the first on-off valve is closed, so that high-temperature and high-pressure refrigerant gas discharged by the compressor flows through the second part of the outdoor heat exchanger, and the first part of the outdoor heat exchanger serves as an evaporator.

Another embodiment of the present application provides an air conditioning system, including: the device comprises a compressor, a first reversing assembly, a second reversing assembly, an indoor heat exchanger, an outdoor heat exchanger assembly and a defrosting branch. A compressor having an air inlet and an air outlet; the first reversing component is provided with first to fourth valve ports, the first valve port is connected with the exhaust port, the fourth valve port is connected with the air suction port, the first valve port is in reversing conduction with one of the second valve port and the third valve port, the fourth valve port is in reversing conduction with the other of the second valve port and the third valve port, the second reversing component is provided with first to third ports, the first port is connected with the exhaust port, the second port is connected with the air suction port, and the third port is in reversing conduction with one of the first port and the second port; the first end of the indoor heat exchanger is connected with the second valve port; the outdoor heat exchanger assembly comprises a first part and a second part, wherein the first end of the first part is connected with the third valve port, the first end of the second part is connected with the third port, a first throttle valve is connected between the second end of the first part and the second end of the indoor heat exchanger, and a second throttle valve is connected between the second end of the second part and the second end of the indoor heat exchanger; the first end of the defrosting branch is connected with the exhaust port, the second end of the defrosting branch is connected to a pipeline between the first throttle valve and the second end of the first part, and the defrosting branch is connected with a first on-off valve in series.

According to the defrosting control method for the air conditioning system, when the air conditioning system is used for defrosting the first part, the defrosting branch is utilized to bypass a part of refrigerant at the exhaust port of the compressor to defrost the first part, at the moment, the second part is closed, so that the second part does not participate in the heating cycle of the air conditioning system, the refrigerant flowing out of the indoor heat exchanger passes through the first part, and the heating cycle of the air conditioning system is further ensured continuously. When the air conditioning system is used for defrosting the second part, a part of refrigerant at the exhaust port of the bypass compressor can be commutated to the second part by the second commutation component, the refrigerant is cooled into a high-temperature medium-pressure gaseous refrigerant in the second part, and the refrigerant flowing out of the second part can flow to the first part, so that the second part can be defrosted by utilizing the latent heat of the refrigerant, and at the moment, the first part can be used as an evaporator to continuously ensure the heating cycle of the air conditioning system. Therefore, the defrosting of the first part and the second part in turn can be realized, the indoor heating state of the indoor heat exchanger is still ensured, the influence on the indoor temperature in the defrosting process of the air conditioning system can be avoided, the indoor temperature can be kept at a high temperature state, and the comfort of a user is improved. And the high-temperature and high-pressure gaseous refrigerant discharged from the exhaust port of the compressor is utilized to defrost the first part, so that the defrosting effect is obvious. The second part is defrosted by utilizing the latent heat of the refrigerant, and the defrosting effect is obvious. Therefore, by means of a defrosting mode combining low-pressure sensible heat and high-pressure waste heat, the advantages of waste heat defrosting and sensible heat defrosting can be utilized, meanwhile, the problems of serious waste of waste heat defrosting capacity, poor sensible heat defrosting reliability and narrow applicable working conditions can be avoided, and the defrosting speed and reliability of an air conditioning system can be improved to a certain extent. In addition, since the first part is located directly above the second part, when defrosting the first part, the second part is not used as an evaporator by fully closing the second throttle valve, so that the problem that the second part is frozen due to the fact that defrosting water of the first part drops onto the second part due to the fact that the second part is used as the evaporator in the defrosting process of the first part can be avoided.

Drawings

Fig. 1 is a schematic diagram of an air conditioning system according to a first embodiment of the present disclosure;

fig. 2 is a schematic diagram of a refrigeration mode of an air conditioning system according to a first embodiment of the present application;

fig. 3 is a schematic diagram of a heating mode of an air conditioning system according to a first embodiment of the present application;

FIG. 4 is a schematic diagram of an air conditioning system according to a first embodiment of the present application defrosting a first section;

FIG. 5 is a schematic diagram of a defrosting of a first portion of an air conditioning system according to a second embodiment of the present disclosure;

fig. 6 is a schematic diagram of an air conditioning system according to a second embodiment of the present disclosure;

fig. 7 is a schematic diagram of an air conditioning system according to a third embodiment of the present disclosure;

fig. 8 is a schematic diagram of an air conditioning system according to a fourth embodiment of the present disclosure;

fig. 9 is a flowchart of a first defrosting control method of an air conditioning system according to an embodiment of the present application;

fig. 10 is a flowchart of a second defrosting control method of the air conditioning system according to the embodiment of the present application;

FIG. 11 is a flowchart of a third defrost control method for an air conditioning system according to an embodiment of the present application;

fig. 12 is a flowchart of a fourth defrosting control method of the air conditioning system according to the embodiment of the present application;

Fig. 13 is a flowchart of a fifth defrosting control method of an air conditioning system according to an embodiment of the present application.

Detailed Description

Embodiments of the present invention will be described in detail below with reference to the accompanying drawings.

The air conditioning system according to the embodiment of the present application is described below.

Referring to fig. 1, fig. 1 is a schematic diagram illustrating an air conditioning system according to a first embodiment of the present application. The embodiment of the application provides an air conditioning system 100, including: the compressor 1, the first reversing assembly 2, the second reversing assembly 5, the indoor heat exchanger 3, the outdoor heat exchanger assembly 4 and the defrosting branch 6.

With continued reference to fig. 1, the compressor 1 has an intake 11 and an exhaust 12. Specifically, the suction port 11 of the compressor 1 is used for sucking air, the refrigerant enters the compression chamber of the compressor 1 through the suction port 11 to be compressed, a high-temperature and high-pressure refrigerant is formed, and the high-temperature and high-pressure refrigerant gas is discharged from the discharge port 12 of the compressor 1 to the compressor 1, and then enters the air conditioning system 100 to circulate the refrigerant.

By way of example, the compressor 1 may be a scroll compressor, a rotor compressor, a screw compressor or other type of compressor.

With continued reference to fig. 1, the first reversing assembly 2 has a first port 21, a second port 22, a third port 23, and a fourth port 24. The first valve port 21 is connected to the exhaust port 12. The fourth port 24 is connected to the suction port 11. The first valve port 21 may be in reverse communication with one of the second valve port 22 and the third valve port 23, and the fourth valve port 24 may be in reverse communication with the other of the second valve port 22 and the third valve port 23. That is, when the first valve port 21 is in conduction with the second valve port 22, the third valve port 23 is in conduction with the fourth valve port 24; when the first port 21 is in communication with the third port 23, the second port 22 is in communication with the fourth port 24.

The first reversing assembly 2 may be a four-way reversing valve, for example. When the four-way reversing valve is electrified, the first valve port 21 is communicated with the second valve port 22, and the third valve port 23 is communicated with the fourth valve port 24; when the four-way reversing valve is powered off, the first valve port 21 is communicated with the third valve port 23, and the second valve port 22 is communicated with the fourth valve port 24. Of course, it will be appreciated that in other examples, when the four-way reversing valve is de-energized, the first port 21 is in communication with the second port 22, and the third port 23 is in communication with the fourth port 24; when the four-way reversing valve is electrified, the first valve port 21 is communicated with the third valve port 23, and the second valve port 22 is communicated with the fourth valve port 24.

With continued reference to fig. 1, the second reversing element 5 has a first port 51, a second port 52, and a third port 53. The first port 51 is connected to the exhaust port 12. The second port 52 is connected to the suction port 11. The third port 53 is commutated to conduct with one of the first and second ports 51, 52. That is, the third port 53 may be in communication with the first port 51, and the third port 53 may also be in communication with the second port 52.

The second reversing assembly 5 may be a three-way reversing valve or a four-way reversing valve, for example. When the second reversing component 5 is a four-way reversing valve, the second reversing component 5 further includes a fourth port, the fourth port is closed, and the fourth port is in reversing conduction with the other of the first port 51 and the second port 52. When the three-way reversing valve or the four-way reversing valve is electrified, the first port 51 is communicated with the third port 53; when the three-way or four-way reversing valve is de-energized, the second port 52 is in communication with the third port 53. Of course, it will be appreciated that in other examples, when the three-way or four-way reversing valve is powered on, the second port 52 is in communication with the third port 53; when the three-way or four-way reversing valve is de-energized, the first port 51 is in communication with the third port 53.

With continued reference to fig. 1, the first end of the indoor heat exchanger 3 is connected to the second valve port 22.

With continued reference to fig. 1, the outdoor heat exchanger assembly 4 includes a first portion 41 and a second portion 42. The first end of the first portion 41 is connected to the third valve opening 23. Therefore, the first end of the first portion 41 may be electrically connected to the third valve opening 23, and the on-off between the first portion 41 and the third valve opening 23 may be controlled by the first reversing component 2 in a reversing manner, which is beneficial to improving the reliability of the air conditioning system 100.

With continued reference to fig. 1, the first end of the second portion 42 is connected to the third port 53. Therefore, the first end of the second portion 42 can be conducted with the third port 53, and the on-off between the second portion 42 and the third port 53 can be controlled through the commutation of the second commutation assembly 5, which is beneficial to improving the reliability of the air conditioning system 100.

With continued reference to fig. 1, a first throttle valve 43 is connected between the second end of the first portion 41 and the second end of the indoor heat exchanger 3. The first throttle valve 43 may serve to throttle and depressurize the refrigerant flowing therethrough. The first throttle valve 43 may also function to control the on-off between the second end of the first portion 41 and the second end of the indoor heat exchanger 3. That is, the opening degree of the first throttle valve 43 is adjustable. The first throttle valve 43 may have a full open state (opening degree is 100%), a full closed state (opening degree is 0), and a throttle state (opening degree is between 0 to 100%). In the fully closed state of the first throttle valve 43, the second end of the first portion 41 is not in communication with the second end of the indoor heat exchanger 3. In the fully opened state and the throttled state of the first throttle valve 43, the second end of the first portion 41 is in communication with the second end of the indoor heat exchanger 3, and in the throttled state, the first throttle valve 43 can throttle and depressurize the refrigerant flowing therethrough.

A second throttle valve 44 is connected between the second end of the second portion 42 and the second end of the indoor heat exchanger 3. The second throttle valve 44 may serve to throttle and depressurize the refrigerant flowing therethrough. The second throttle valve 44 may also function to control the on-off between the second end of the second portion 42 and the second end of the indoor heat exchanger 3. That is, the opening degree of the second throttle valve 44 is adjustable. The second throttle valve 44 may have a full open state (opening degree is 100%), a full closed state (opening degree is 0), and a throttle state (opening degree is between 0 to 100%). In the fully closed state of the second throttle valve 44, the second end of the second portion 42 is not in communication with the second end of the indoor heat exchanger 3. In the fully opened state and the throttled state of the first portion 41, the second end of the second portion 42 is in communication with the second end of the indoor heat exchanger 3, and in the throttled state, the second throttle valve 44 may throttle and depressurize the refrigerant flowing therethrough.

Thus, the opening/closing of the first throttle valve 43 can be controlled to open/close the second end of the first portion 41 and the second end of the indoor heat exchanger 3, and the refrigerant flowing through the first throttle valve 43 can be throttled and depressurized by controlling the opening/closing of the first throttle valve 43. The opening and closing of the second throttle valve 44 can be controlled to control the on-off between the second end of the second portion 42 and the second end of the indoor heat exchanger 3, and the refrigerant flowing through the first throttle valve 43 can be throttled and depressurized by controlling the opening degree of the first throttle valve 43. Thereby contributing to an improvement in stability and reliability of the air conditioning system 100.

With continued reference to fig. 1, the defrost branch 6 is connected at a first end to the exhaust port 12. The second end of the defrost branch 6 is connected to a line between the first throttle valve 43 and the second end of the first portion 41. The defrosting branch 6 is connected in series with a first on-off valve 61. The first on-off valve 61 can control the on-off of the defrost branch 6. It will be appreciated that the second end of the defrost branch 6 is located between the first throttle valve 43 and the second end of the first portion 41, and the refrigerant in the defrost branch 6 can avoid the first throttle valve 43 to directly enter the first portion 41, so that the first throttle valve 43 can be prevented from affecting the state of the refrigerant on the defrost branch 6, and thus the state of the refrigerant on the defrost branch 6 at high temperature and high pressure can be ensured. On the other hand, when frost is present on the first portion 41, the first on-off valve 61 is controlled to be opened, so that the high-temperature and high-pressure gaseous refrigerant discharged from the discharge port 12 can enter the first portion 41 along the defrosting branch 6, thereby defrosting the first portion 41 by utilizing sensible heat of the discharge of the compressor 1. Meanwhile, when the first part 41 is not required to defrost, the first on-off valve 61 can be controlled to be closed, so that the high-temperature and high-pressure gaseous refrigerant discharged from the air outlet 12 can be prevented from flowing to the defrosting branch 6, thereby influencing the normal operation of the air conditioning system 100 and being beneficial to improving the operation reliability of the air conditioning system 100.

The air conditioning system 100 according to the embodiment of the present application has a cooling mode, a heating mode, and a defrosting mode. The control process and the flow direction of the refrigerant in the cooling mode, the heating mode and the defrosting mode according to the embodiment of the present application are described in detail below.

Refrigeration mode

Referring to fig. 2, fig. 2 is a schematic diagram of a refrigeration mode of an air conditioning system according to a first embodiment of the present application. When the air conditioning system 100 is in the cooling mode, the first port 21 of the first reversing assembly 2 is in communication with the third port 23, the second port 22 is in communication with the fourth port 24, the first port 51 of the second reversing assembly 5 is in communication with the third port 53, the first throttle 43 is throttled, and the second throttle 44 is throttled.

The flow direction of the refrigerant is as follows: the high-temperature and high-pressure gaseous refrigerant discharged from the discharge port 12 of the compressor 1 flows to the first reversing assembly 2 and the second reversing assembly 5, respectively, the refrigerant flowing to the first reversing assembly 2 flows into the first reversing assembly 2 through the first valve port 21, and flows out of the first reversing assembly 2 through the third valve port 23. The refrigerant flowing out of the third valve port 23 flows into the first portion 41, and is sufficiently heat-exchanged in the first portion 41 to become a high-pressure medium-temperature liquid refrigerant. Then, the refrigerant flowing out of the first portion 41 flows through the first throttle valve 43 to be throttled and depressurized, and then becomes a low-temperature low-pressure two-phase refrigerant. The refrigerant flowing toward the second reversing element 5 flows into the second reversing element 5 through the first port 51 and out of the second reversing element 5 through the third port 53. The refrigerant flowing out of the third port 53 flows into the second portion 42, and becomes a high-pressure medium-temperature liquid refrigerant after sufficient heat exchange in the second portion 42. Then, the refrigerant flowing out of the second portion 42 flows through the second throttle valve 44 to be throttled and depressurized, and then becomes a low-temperature low-pressure two-phase refrigerant. The refrigerant throttled and depressurized by the first throttle valve 43 and the refrigerant throttled and depressurized by the second throttle valve 44 flow into the indoor heat exchanger 3, and are changed into low-temperature low-pressure gaseous refrigerant after heat exchange by the indoor heat exchanger 3, and finally flow back to the air suction port 11 of the compressor 1 through the second valve port 22 and the fourth valve port 24 in sequence, so that the refrigeration cycle of the air conditioning system 100 is completed.

Heating mode

Referring to fig. 3, fig. 3 is a schematic diagram of a heating mode of an air conditioning system according to a first embodiment of the present application. When the air conditioning system 100 is in the heating mode, the first valve port 21 and the second valve port 22 of the first reversing assembly 2 are controlled to be communicated, the third valve port 23 and the fourth valve port 24 are controlled to be communicated, the second port 52 and the third port 53 of the second reversing assembly 5 are controlled to be communicated, the first throttle valve 43 is throttled, the second throttle valve 44 is throttled, and the first on-off valve 61 is closed.

The flow direction of the refrigerant is as follows: the high-temperature and high-pressure gaseous refrigerant discharged from the discharge port 12 of the compressor 1 flows into the first reversing assembly 2 through the first valve port 21, and flows out of the first reversing assembly 2 through the second valve port 22. The refrigerant flowing out of the second valve port 22 flows into the indoor heat exchanger 3, exchanges heat in the indoor heat exchanger 3, becomes a high-pressure medium-temperature liquid refrigerant, flows out of the indoor heat exchanger 3, flows into the first throttle valve 43 and the second throttle valve 44, respectively, throttles the refrigerant by the first throttle valve 43, and flows into the first portion 41, and evaporates in the first portion 41 into a low-temperature low-pressure two-phase refrigerant. The refrigerant throttled and depressurized by the second throttle valve 44 flows into the second portion 42, evaporates into two-phase refrigerant of low temperature and low pressure in the second portion 42, and finally flows back to the air suction port 11 of the compressor 1 through the third port 53 and the second port 52 in sequence, and flows back to the air suction port 11 of the compressor 1 through the third port 23 and the fourth port 24 in sequence, so as to complete the heating cycle of the air conditioning system 100.

Defrosting mode

Referring to fig. 4, fig. 4 is a schematic diagram of an air conditioning system according to a first embodiment of the present application for defrosting a first portion. In some embodiments, when defrosting the first portion 41, the first valve port 21 and the second valve port 22 of the first reversing assembly 2 are controlled to be communicated, the third valve port 23 and the fourth valve port 24 are controlled to be communicated, the third port 53 and the second port 52 of the second reversing assembly 5 are controlled to be communicated, the first throttle valve 43 is controlled to be fully closed, the second throttle valve 44 is controlled to throttle, and the first on-off valve 61 is controlled to be opened.

The flow direction of the refrigerant is as follows: the high-temperature and high-pressure gaseous refrigerant discharged from the discharge port 12 of the compressor 1 flows into the first reversing unit 2 and the defrost branch 6, respectively, and the high-temperature and high-pressure gaseous refrigerant flowing into the defrost branch 6 flows into the first portion 41, and frost of the first portion 41 is removed by sensible heat of the high-temperature and high-pressure gaseous refrigerant discharged from the compressor 1. The refrigerant flowing toward the first reversing assembly 2 flows into the first reversing assembly 2 through the first valve port 21 and flows out of the first reversing assembly 2 from the second valve port 22. The refrigerant flowing out of the second valve port 22 flows into the indoor heat exchanger 3, is changed into a high-temperature and high-pressure two-phase refrigerant after heat exchange in the indoor heat exchanger 3, then flows out of the indoor heat exchanger 3 and flows into the second throttle valve 44, the refrigerant throttled and depressurized by the second throttle valve 44 flows into the second part 42, is evaporated into a low-temperature and low-pressure gaseous refrigerant in the second part 42, and then flows out of the second part 42. Finally, the refrigerant flowing out of the second portion 42 flows back to the air suction port 11 of the compressor 1 through the third port 53 and the second port 52 in sequence, and the refrigerant flowing out of the first portion 41 flows back to the air suction port 11 of the compressor 1 through the third valve port 23 and the fourth valve port 24 in sequence, so that the defrosting refrigerant circulation of the first portion 41 is completed.

In other embodiments, when defrosting the first portion 41, the first valve port 21 of the first reversing assembly 2 is controlled to be communicated with the second valve port 22, the third valve port 23 is controlled to be communicated with the fourth valve port 24, the second port 52 of the second reversing assembly 5 is controlled to be communicated with the third port 53, the first throttle 43 is throttled, the second throttle 44 is fully closed, and the first on-off valve 61 is opened.

The flow direction of the refrigerant is as follows: the high-temperature and high-pressure gaseous refrigerant discharged from the discharge port 12 of the compressor 1 flows into the first reversing assembly 2 and the defrost branch 6, respectively, and the high-temperature and high-pressure gaseous refrigerant flowing into the defrost branch 6 flows into the first portion 41. The refrigerant flowing toward the first reversing assembly 2 flows into the first reversing assembly 2 through the first valve port 21 and flows out of the first reversing assembly 2 from the second valve port 22. The refrigerant flowing out of the second valve port 22 flows into the indoor heat exchanger 3, is changed into a high-temperature and high-pressure two-phase refrigerant after heat exchange in the indoor heat exchanger 3, flows out of the indoor heat exchanger 3 and flows into the first throttle valve 43, and the refrigerant throttled and depressurized by the first throttle valve 43 flows into the first portion 41. The high-temperature and high-pressure gaseous refrigerant flowing out of the defrosting branch 6 and the low-temperature and low-pressure two-phase refrigerant flowing out of the first throttle valve 43 flow into the first portion 41, and frost in the first portion 41 is removed. The refrigerant flowing out of the first portion 41 flows back to the suction port 11 of the compressor 1 through the third port 23 and the fourth port 24, and thus the defrost refrigerant cycle of the first portion 41 is completed.

Referring to fig. 5, fig. 5 is a schematic diagram of an air conditioning system according to a first embodiment of the present application for defrosting a second portion. When defrosting the second part 42, the first valve port 21 and the second valve port 22 of the first reversing assembly 2 are controlled to be communicated, the third valve port 23 and the fourth valve port 24 are controlled to be communicated, the first port 51 and the third port 53 of the second reversing assembly 5 are controlled to be communicated, the first throttle valve 43 is controlled to throttle, the second throttle valve 44 is controlled to be fully opened, and the first on-off valve 61 is controlled to be closed.

The flow direction of the refrigerant is as follows: the high-temperature and high-pressure gaseous refrigerant discharged from the discharge port 12 of the compressor 1 flows to the first reversing assembly 2 and the second reversing assembly 5, respectively. The refrigerant flowing toward the first reversing assembly 2 flows into the first reversing assembly 2 through the first valve port 21 and flows out of the first reversing assembly 2 from the second valve port 22. The refrigerant flowing out of the second valve port 22 flows into the indoor heat exchanger 3, and the high-temperature and high-pressure gaseous refrigerant exchanges heat with the Cheng Gaowen high-pressure two-phase refrigerant in the indoor heat exchanger 3. Flows out of the indoor heat exchanger 3 to the first throttle valve 43, throttles down by the first throttle valve 43, and flows to the first portion 41. The refrigerant flowing toward the second reversing element 5 flows into the second reversing element 5 through the first port 51 and out of the second reversing element 5 through the third port 53. The refrigerant flowing out of the third port 53 flows into the second portion 42, so that the high-temperature and high-pressure gaseous refrigerant discharged from the compressor 1 is cooled in the second portion 42 to a high-pressure and medium-temperature liquid refrigerant, and the second portion 42 is defrosted by using the latent heat of the refrigerant. The refrigerant flowing out of the second portion 42 flows through the second throttle valve 44 to the first throttle valve 43, throttled down by the first throttle valve 43, and then flows to the first portion 41. Finally, the refrigerant flowing out of the first portion 41 flows back to the suction port 11 of the compressor 1 through the third port 23 and the fourth port 24, and thus the defrost refrigerant cycle of the second portion 42 is completed.

Thus, when the air conditioning system 100 defrost the first portion 41, the defrosting branch 6 bypasses a part of the refrigerant at the exhaust port 12 of the compressor 1 to the first portion 41, and at this time, the second portion 42 may continue to ensure the heating cycle of the air conditioning system 100 as an evaporator, or the second portion 42 may be turned off, so that the second portion 42 does not participate in the heating cycle of the air conditioning system 100, but the refrigerant flowing out of the indoor heat exchanger 3 passes through the first portion 41, and further, the heating cycle of the air conditioning system 100 may continue to be ensured. When the air conditioning system 100 defrost the second portion 42, a part of the refrigerant bypassing the discharge port 12 of the compressor 1 may be commutated to the second portion 42 by the second commutation unit 5, the refrigerant may be cooled to a high-temperature medium-pressure gaseous refrigerant in the second portion 42, and the refrigerant flowing out of the second portion 42 may flow to the first portion 41, so that the second portion 42 may be defrosted by using latent heat of the refrigerant, and at this time, the first portion 41 may serve as an evaporator to continuously ensure a heating cycle of the air conditioning system 100. Therefore, the defrosting of the first part 41 and the second part 42 in turn can be realized, and meanwhile, the indoor heating state of the indoor heat exchanger 3 is still ensured, the influence on the indoor temperature in the defrosting process of the air conditioning system 100 can be avoided, the indoor temperature can be kept, and the comfort of a user is improved. And the first portion 41 is defrosted by the high-temperature and high-pressure gaseous refrigerant discharged from the discharge port 12 of the compressor 1, and the defrosting effect is remarkable. The second portion 42 is defrosted by using latent heat of the refrigerant, and the defrosting effect is remarkable. Therefore, by means of the defrosting mode combining low-pressure sensible heat and high-pressure waste heat, the advantages of waste heat defrosting and sensible heat defrosting can be utilized, meanwhile, the problems of serious waste of waste heat defrosting capacity, poor sensible heat defrosting reliability and narrow applicable working conditions can be avoided, and the defrosting speed and reliability of the air conditioning system 100 can be improved to a certain extent.

With continued reference to fig. 5, the first portion 41 may be located directly above the second portion 42. Therefore, the defrosting branch circuit 6 can be reasonably arranged, which is beneficial to reducing the cost.

Referring to fig. 6, fig. 6 is a schematic diagram of an air conditioning system according to a second embodiment of the present application, where the first portion 41 may also be located directly below the second portion 42. Therefore, the defrosting branch circuit 6 can be reasonably arranged, which is beneficial to reducing the cost.

Illustratively, first portion 41 may be located to the left of second portion 42 or first portion 41 may be located to the right of second portion 42 along the length of first portion 41.

Referring to fig. 5, the first and second throttle valves 43 and 44 may be electronic expansion valves. This arrangement can improve the operation speed and accuracy of the air conditioning system 100. In other embodiments, the first and second throttles 43, 44 may also be thermal expansion valves.

In some embodiments, first portion 41 and second portion 42 may be split into two separate heat exchangers. Thus, when the air conditioning system 100 is in the cooling or heating mode, it is possible to avoid the occurrence of the condition that the air conditioning system 100 stops operating when one of the first portion 41 and the second portion 42 is damaged, and to improve the stability and reliability of the operation of the air conditioning system 100.

In other embodiments, the first portion 41 and the second portion 42 may be divided into two portions of the same heat exchanger. This arrangement facilitates assembly of the air conditioning system 100, thereby facilitating an improvement in assembly efficiency of the air conditioning system 100.

In some embodiments, the first on-off valve 61 may be a solenoid valve. This arrangement is advantageous in improving the response speed and reliability of the air conditioning system 100.

In other embodiments, the first on-off valve 61 may also be an electronic expansion valve.

With continued reference to fig. 5, a first end of the indoor heat exchanger 3 is connected to a first stop valve 31, and a second end of the indoor heat exchanger 3 is connected to a second stop valve 32. Thus, by providing the first and second shut-off valves 31 and 32, maintenance and overhaul of the air conditioning system 100 is facilitated. Specifically, when the indoor heat exchanger 3 needs to be repaired or replaced, the first stop valve 31 and the second stop valve 32 can be closed, so that the indoor heat exchanger 3 can be more conveniently repaired without discharging the refrigerant of the whole air conditioning system 100.

For example, the air conditioning system 100 may be a multi-split system. The air conditioning system 100 includes a plurality of indoor units. An indoor heat exchanger 3 is arranged in each indoor unit. The indoor units are connected in parallel. The first ends of the indoor heat exchangers 3 of the plurality of indoor units may be connected to the first shut-off valve 31. The second ends of the indoor heat exchangers 3 of the plurality of indoor units may be connected to the second shut-off valve 32. It will of course be appreciated that in other examples, the air conditioning system 100 may include only one indoor unit.

With continued reference to fig. 5, in some embodiments, the air conditioning system 100 further includes a gas-liquid separator 7. A gas-liquid separator 7 is arranged between the compressor 1 and the first reversing assembly 2. The gas-liquid separator 7 has a liquid inlet 71 and a gas outlet 72. The liquid inlet 71 is connected to the fourth valve port 24. The gas outlet 72 is connected to the suction port 11. By arranging the gas-liquid separator 7, the gas-liquid separation effect can be carried out on the refrigerant entering the compressor 1, so that the problem of liquid impact on the compressor 1 is avoided, and the compressor 1 is protected.

With continued reference to fig. 7, fig. 7 is a schematic diagram illustrating an air conditioning system according to a third embodiment of the present disclosure. In some embodiments, the air conditioning system 100 further comprises a heating device 73, the heating device 73 being used for heating the gas-liquid separator 7. By this arrangement, the liquid refrigerant accumulated in the gas-liquid separator 7 can be evaporated, and the pressure and temperature of the gaseous refrigerant at the gas outlet 72 of the gas-liquid separator 7 can be increased, and thus the discharge pressure and discharge temperature of the compressor 1 can be increased, and the defrosting speed of the air conditioning system 100 can be increased.

The heating device 73 may be provided at the bottom of the gas-liquid separator 7, for example.

With continued reference to fig. 8, fig. 8 is a schematic diagram illustrating an air conditioning system according to a fourth embodiment of the present disclosure. The air conditioning system 100 further includes a first subcooling device 46 and a second subcooling device 47. The first supercooling means 46 is connected between the first throttle valve 43 and the second end of the indoor heat exchanger 3, and the second supercooling means 47 is connected between the second throttle valve 44 and the second end of the indoor heat exchanger 3. Thus, the first portion 41 and the second portion 42 can be isolated, so that the problem that the defrosting effect is poor between the end of the first portion 41 close to the second portion 42 and the end of the second portion 42 close to the first portion 41 when the air conditioning system 100 performs defrosting can be avoided, and the defrosting effect of the air conditioning system 100 can be improved. Meanwhile, the flash gas generated in the throttling process of the air conditioning system 100 can be reduced, the refrigerating capacity of the air conditioning system 100 can be improved, and the running stability of the compressor 1 can be improved, so that the stability and reliability of the air conditioning system 100 can be improved.

With continued reference to fig. 8, in some embodiments, one side of the outdoor heat exchanger assembly 4 may be provided with an outdoor fan 45. This arrangement can improve the heat exchange efficiency of the outdoor heat exchanger assembly 4.

With continued reference to fig. 8, in some embodiments, one side of the indoor heat exchanger 3 may be provided with an indoor fan 33. This arrangement can improve the heat exchange efficiency of the indoor heat exchanger 3.

Based on the above-described structure of the air conditioning system 100, there are four defrosting methods of the air conditioning system 100 according to the embodiment of the present application. The defrosting control method of the air conditioning system 100 according to the first embodiment of the present application will be described below.

Referring to fig. 9, fig. 9 is a flowchart of a first defrosting control method of an air conditioning system according to an embodiment of the present application. The defrosting control method of the air conditioning system 100 includes the steps of:

s1: when the air conditioning system 100 operates in the heating mode, it is determined whether the air conditioning system 100 satisfies a defrosting condition. When the air conditioning system 100 is in the heating mode, the first valve port 21 and the second valve port 22 of the first reversing assembly 2 are communicated, the third valve port 23 and the fourth valve port 24 are communicated, the second port 52 and the third port 53 of the second reversing assembly 5 are communicated, the first throttle valve 43 is throttled, the second throttle valve 44 is throttled, and the first on-off valve 61 is closed.

S2: if the air conditioning system 100 satisfies the defrosting condition, the first throttle valve 43 is controlled to be fully closed, and the first on-off valve 61 is opened, so that the air conditioning system 100 operates in the first defrosting mode to defrost the first portion 41.

Thus, in the first defrosting mode, the first valve port 21 and the second valve port 22 of the first reversing assembly 2 are kept in conduction, the third valve port 23 and the fourth valve port 24 are kept in conduction, the third port 53 and the second port 52 of the second reversing assembly 5 are kept in conduction, the first throttle valve 43 is controlled to be fully closed, the second throttle valve 44 is throttled, and the first on-off valve 61 is opened. At this time, the flow direction of the refrigerant in the first defrost mode may be: the high-temperature and high-pressure gaseous refrigerant discharged from the discharge port 12 of the compressor 1 flows into the first reversing unit 2 and the defrost branch 6, respectively, and the high-temperature and high-pressure gaseous refrigerant flowing into the defrost branch 6 flows into the first portion 41, and frost of the first portion 41 is removed by sensible heat of the high-temperature and high-pressure gaseous refrigerant discharged from the compressor 1. The refrigerant flowing toward the first reversing assembly 2 flows into the first reversing assembly 2 through the first valve port 21 and flows out of the first reversing assembly 2 from the second valve port 22. The refrigerant flowing out of the second valve port 22 flows into the indoor heat exchanger 3, is changed into a high-temperature and high-pressure two-phase refrigerant after heat exchange in the indoor heat exchanger 3, then flows out of the indoor heat exchanger 3 and flows into the second throttle valve 44, the refrigerant throttled and depressurized by the second throttle valve 44 flows into the second part 42, is evaporated into a low-temperature and low-pressure gaseous refrigerant in the second part 42, and then flows out of the second part 42. Finally, the refrigerant flowing out of the second portion 42 flows back to the suction port 11 of the compressor 1 through the third port 53 and the second port 52 in sequence, and the refrigerant flowing out of the first portion 41 flows back to the suction port 11 of the compressor 1 through the third port 23 and the fourth port 24 in sequence.

S3: judging whether the air conditioning system 100 satisfies a first defrosting mode end condition;

s4: if the air conditioning system 100 satisfies the first defrosting mode end condition, the first port 51 is controlled to be communicated with the third port 53, the first throttle valve 43 is throttled, the second throttle valve 44 is fully opened, and the first on-off valve 61 is closed, so that the air conditioning system 100 is controlled to exit the first defrosting mode, and the second defrosting mode is operated, in which the second portion 42 is defrosted.

Thus, in the second defrosting mode, the first port 21 and the second port 22 of the first reversing assembly 2 are kept in conduction, the third port 23 and the fourth port 24 are kept in conduction, the first port 51 and the third port 53 of the second reversing assembly 5 are controlled to be in conduction, the first throttle 43 is controlled to throttle, the second throttle 44 is controlled to be fully opened, and the first on-off valve 61 is controlled to be closed. At this time, the flow direction of the refrigerant in the second defrost mode may be: the high-temperature and high-pressure gaseous refrigerant discharged from the discharge port 12 of the compressor 1 flows to the first reversing assembly 2 and the second reversing assembly 5, respectively. The refrigerant flowing toward the first reversing assembly 2 flows into the first reversing assembly 2 through the first valve port 21 and flows out of the first reversing assembly 2 from the second valve port 22. The refrigerant flowing out of the second valve port 22 flows into the indoor heat exchanger 3, and the high-temperature and high-pressure gaseous refrigerant exchanges heat with the Cheng Gaowen high-pressure two-phase refrigerant in the indoor heat exchanger 3. Flows out of the indoor heat exchanger 3 to the first throttle valve 43, throttles down by the first throttle valve 43, and flows to the first portion 41. The refrigerant flowing toward the second reversing element 5 flows into the second reversing element 5 through the first port 51 and out of the second reversing element 5 through the third port 53. The refrigerant flowing out of the third port 53 flows into the second portion 42, so that the high-temperature and high-pressure gaseous refrigerant discharged from the compressor 1 is cooled in the second portion 42 to a high-pressure and medium-temperature liquid refrigerant, and the second portion 42 is defrosted by using the latent heat of the refrigerant. The refrigerant flowing out of the second portion 42 flows through the second throttle valve 44 to the first throttle valve 43, throttled down by the first throttle valve 43, and then flows to the first portion 41. Finally, the refrigerant flowing out of the first portion 41 flows back to the suction port 11 of the compressor 1 through the third port 23 and the fourth port 24.

S5: judging whether the air conditioning system 100 satisfies a second defrosting mode end condition;

s6: if the second defrost mode end condition is satisfied, the second port 52 of the second reversing assembly 5 is controlled to be conducted with the third port 53, and the second throttle valve 44 throttles to exit the second defrost mode and operate the heating mode.

Therefore, when the heating mode is switched to the first defrosting mode and the second defrosting mode for defrosting the first portion 41 and the second portion 42, the first reversing assembly 2 is not reversed all the time, so that the power consumption of the air conditioning system 100 can be reduced, the air conditioning system 100 can realize uninterrupted heating, the indoor can be kept in a high-temperature state all the time, and the comfort of a user can be improved. Meanwhile, the first defrosting mode utilizes the high-temperature and high-pressure gaseous refrigerant discharged from the exhaust port 12 of the compressor 1 to defrost the first part 41, and the defrosting effect is obvious. The second defrosting mode uses the second reversing component 5 to reverse a part of refrigerant at the exhaust port 12 of the bypass compressor 1 to the second part 42, and enables the refrigerant to be cooled into a high-temperature medium-pressure gaseous refrigerant in the second part 42, and enables the refrigerant flowing out of the second part 42 to flow to the first part 41, so that the second part 42 can be defrosted by utilizing latent heat of the refrigerant, and the advantage of waste heat defrosting and sensible heat defrosting can be utilized by a defrosting mode combining low-pressure sensible heat and high-pressure waste heat, meanwhile, the problems of serious waste heat defrosting capability, poor sensible heat defrosting reliability and narrow applicable working conditions can be avoided, and the reliability and stability of the operation of the air conditioning system 100 can be improved.

In some embodiments, first portion 41 is positioned directly above second portion 42, and in a first defrost mode, first portion 41 is defrosted and in a second defrost mode, second portion 42 is defrosted. Thus, when the first portion 41 is located directly above the second portion 42, during the defrosting of the outdoor heat exchanger assembly 4, by defrosting the first portion 41 first, and then defrosting the second portion 42 after the defrosting of the first portion 41 is completed, it is beneficial to ensure the defrosting effect of the outdoor heat exchanger assembly 4, and the problem that the defrosting effect of the second portion 42 is deteriorated due to the defrosting of the second portion 42 first and then the defrosting of the first portion 41 is prevented, and when the defrosted water of the first portion 41 drops onto the second portion 42 as an evaporator, the second portion 42 is frozen.

In some embodiments, to increase the evaporation capacity of the first portion 41, the outdoor fan 45 is disposed at a side of the first portion 41 away from the second portion 42, and if the air conditioning system 100 satisfies the first defrosting mode end condition in step S4, the outdoor fan 45 is controlled to be turned on so that air can be supplied to the first portion 41 during defrosting of the second portion 42. Thus, after the defrosting of the first portion 41 is completed, the outdoor fan 45 is turned on to improve the evaporation capacity of the first portion 41, and further to improve the suction pressure of the compressor 1, so that the indoor side can be quickly discharged after the defrosting of the air conditioning system 100 is completed, which is beneficial to improving the use experience of users.

In some embodiments, the outdoor ambient temperature Ta, the temperature Te1 at the second end of the first portion 41, and the temperature Tg2 at the second end of the second portion 42 are obtained before the air conditioning system 100 is determined to satisfy the defrost condition. If Ta is less than or equal to a and Te1/Tg2 is less than or equal to b, and the continuous operation time of the air conditioning system 100 in the heating mode reaches the first set duration, the conditioning system is judged to meet the defrosting condition. Thus, the air conditioning system 100 can accurately judge whether to defrost, which is beneficial to improving the sensitivity and reliability of the air conditioning system 100 in defrosting.

For example, an outdoor temperature sensor may be provided at the outside of the air conditioning system 100 for acquiring the outdoor ambient temperature Ta, a first portion Te temperature sensor may be provided at the second end of the first portion 41 for acquiring the temperature Te1 of the second end of the first portion 41, and a second portion temperature sensor 421 may be provided at the second end of the second portion 42 for acquiring the temperature Tg2 of the second end of the second portion 42.

In some embodiments, -7 ℃ < a < 7 ℃. For example, the threshold value a of the outdoor ambient temperature Ta may be-6 ℃, -5 ℃, -4 ℃, -3 ℃, -2 ℃, -1 ℃, 0 ℃, 1 ℃, 2 ℃, 3 ℃, 4 ℃, 5 ℃, 6 ℃ or the like.

In some embodiments, b is-5 ℃ to 0 ℃. For example, the ratio Te1/Tg2 may be-5 ℃, -4 ℃, -3 ℃, -2 ℃, -1 ℃ or 0 ℃ or the like.

In some embodiments, the first set period of time is greater than or equal to 10 minutes. For example, the value of the first set period of time may be 10min, 11min, 12min, 13min, or 14 min.

In some embodiments, the first defrost mode end condition is: the temperature Tg1 at the first end of the first portion 41 is greater than or equal to Tgo1 and is maintained for a first predetermined time. Therefore, when the first defrosting mode end condition is met, the first defrosting mode can be timely exited, so that the intelligent degree and reliability of the air conditioning system 100 can be improved.

Illustratively, in the embodiment depicted in FIG. 8, a first portion temperature sensor 411 may be provided at the first end of the first portion 41 for acquiring the temperature Tg1 at the first end of the second portion 42.

In some embodiments, the second defrost mode end condition is: the temperature Tg2 at the second end of the second portion 42 is greater than or equal to Tgo2 for a second predetermined time. Therefore, the second defrosting mode can be timely exited when the second defrosting mode ending condition is met, so that the intelligent degree and the reliability of the air conditioning system 100 are improved.

In some embodiments, 10 ℃ or less than Tgo1 or less than 25 ℃. For example, tgo may be 10 ℃, 11 ℃, 12 ℃, 13 ℃, 14 ℃, 15 ℃, 16 ℃, 17 ℃, 18 ℃, 19 ℃, 20 ℃, 21 ℃, 22 ℃, 23 ℃, 24 ℃, 25 ℃, or the like.

In some embodiments, 5 seconds or less the first preset time or less than 30 seconds. For example, the first preset time may take a value of 5 seconds, 10 seconds, 15 seconds, 20 seconds, 25 seconds, 30 seconds, or the like.

In some embodiments, 10 ℃ or less than Tgo2 or less than 25 ℃. For example, tgo may be 10 ℃, 11 ℃, 12 ℃, 13 ℃, 14 ℃, 15 ℃, 16 ℃, 17 ℃, 18 ℃, 19 ℃, 20 ℃, 21 ℃, 22 ℃, 23 ℃, 24 ℃, 25 ℃, or the like.

In some embodiments, 5 seconds or less and the second preset time or less than 30 seconds. For example, the second preset time may take a value of 5 seconds, 10 seconds, 15 seconds, 20 seconds, 25 seconds, 30 seconds, or the like.

A second defrosting control method of the air conditioning system 100 according to the embodiment of the present application is described below. The second defrosting control method is a defrosting control method of the air conditioning system 100 based on the first portion 41 being located directly above the second portion 42.

Referring to fig. 10, fig. 10 is a flowchart of a second defrosting control method of an air conditioning system according to an embodiment of the present application. The defrosting control method of the air conditioning system 100 includes the steps of:

S2: if the air conditioning system 100 satisfies the defrosting condition, the second throttle valve 44 is controlled to be fully closed, and the first on-off valve 61 is opened, so that the air conditioning system 100 operates in the first defrosting mode to defrost the first portion 41.

Thus, in the first defrost mode, the first port 21 and the second port 22 of the first reversing assembly 2 are kept in conduction, the third port 23 and the fourth port 24 are kept in conduction, the second port 52 and the third port 53 of the second reversing assembly 5 are kept in conduction, the first throttle 43 is throttled, the second throttle 44 is fully closed, and the first on-off valve 61 is opened. At this time, the flow direction of the refrigerant in the first defrost mode may be: the high-temperature and high-pressure gaseous refrigerant discharged from the discharge port 12 of the compressor 1 flows into the first reversing assembly 2 and the defrost branch 6, respectively, and the high-temperature and high-pressure gaseous refrigerant flowing into the defrost branch 6 flows into the first portion 41. The refrigerant flowing toward the first reversing assembly 2 flows into the first reversing assembly 2 through the first valve port 21 and flows out of the first reversing assembly 2 from the second valve port 22. The refrigerant flowing out of the second valve port 22 flows into the indoor heat exchanger 3, is changed into a high-temperature and high-pressure two-phase refrigerant after heat exchange in the indoor heat exchanger 3, flows out of the indoor heat exchanger 3 and flows into the first throttle valve 43, and the refrigerant throttled and depressurized by the first throttle valve 43 flows into the first portion 41. The high-temperature and high-pressure gaseous refrigerant flowing out of the defrosting branch 6 and the low-temperature and low-pressure two-phase refrigerant flowing out of the first throttle valve 43 flow into the first portion 41, and frost in the first portion 41 is removed. The refrigerant flowing out of the first portion 41 flows back to the suction port 11 of the compressor 1 through the third port 23 and the fourth port 24.

s4: if the air conditioning system 100 satisfies the first defrosting mode end condition, the first port 51 is controlled to be communicated with the third port 53, the second throttle valve 44 is fully opened, and the first on-off valve 61 is closed to control the air conditioning system 100 to exit the first defrosting mode and operate the second defrosting mode, and defrost the second portion 42 in the second defrosting mode.

Therefore, when the heating mode is switched to the first defrosting mode and the second defrosting mode for defrosting the first portion 41 and the second portion 42, the first reversing assembly 2 is not reversed all the time, so that the power consumption of the air conditioning system 100 can be reduced, the air conditioning system 100 can realize uninterrupted heating, the indoor can be kept in a high-temperature state all the time, and the comfort of a user can be improved. The second defrosting mode uses the second reversing component 5 to reverse a part of refrigerant at the exhaust port 12 of the bypass compressor 1 to the second part 42, and enables the refrigerant to be cooled into a high-temperature medium-pressure gaseous refrigerant in the second part 42, and enables the refrigerant flowing out of the second part 42 to flow to the first part 41, so that the second part 42 can be defrosted by utilizing latent heat of the refrigerant, and the advantage of waste heat defrosting and sensible heat defrosting can be utilized by a defrosting mode combining low-pressure sensible heat and high-pressure waste heat, meanwhile, the problems of serious waste heat defrosting capability, poor sensible heat defrosting reliability and narrow applicable working conditions can be avoided, and the reliability and stability of the operation of the air conditioning system 100 can be improved. Further, since the first portion 41 is located directly above the second portion 42, the second portion 42 is not used as an evaporator by closing the second throttle valve 44 entirely when the first portion 41 is defrosted, and thus, the problem of freezing of the second portion 42 due to the fact that the defrosted water of the first portion 41 drops onto the second portion 4 when the second portion 42 is used as an evaporator during defrosting of the first portion 41 can be avoided.

In some embodiments, in a first defrost mode, first portion 41 is defrosted and in a second defrost mode, second portion 42 is defrosted. Therefore, since the first portion 41 is located directly above the second portion 42, during the defrosting of the outdoor heat exchanger assembly 4, by defrosting the first portion 41 first, and then defrosting the second portion 42 after the defrosting of the first portion 41 is completed, it is beneficial to ensure the defrosting effect of the outdoor heat exchanger assembly 4, and the problem that the defrosting effect of the second portion 42 is deteriorated due to defrosting the second portion 42 first and then defrosting the first portion 41 is prevented, and when the defrosted water of the first portion 41 drops onto the second portion 42 as an evaporator, the second portion 42 is frozen.

For example, in the embodiment illustrated in fig. 8, a first portion temperature sensor 411 may be provided at the first end of the first portion 41 for acquiring the temperature Tg1 of the first end of the second portion 42. An outdoor temperature sensor is provided at the outside of 100 for acquiring an outdoor ambient temperature Ta, a first portion Te temperature sensor may be provided at the second end of the first portion 41 for acquiring a temperature Te1 of the second end of the first portion 41, and a second portion temperature sensor 421 may be provided at the second end of the second portion 42 for acquiring a temperature Tg2 of the second end of the second portion 42.

In some embodiments, 5 seconds or less and the second preset time or less than 30 seconds. For example, the first preset time may take a value of 5 seconds, 10 seconds, 15 seconds, 20 seconds, 25 seconds, 30 seconds, or the like.

A third defrosting control method of the air conditioning system 100 of the embodiment of the present application is explained below.

Referring to fig. 11, fig. 11 is a flowchart of a third defrosting control method of an air conditioning system according to an embodiment of the present application. The defrosting control method of the air conditioning system 100 includes the steps of:

S2: if the air conditioning system 100 satisfies the defrost condition, the first port 51 and the third port 53 of the second reversing assembly 5 are controlled to be in communication, and the second throttle valve 44 is fully opened, so that the air conditioning system 100 operates in the first defrost mode to defrost the second portion 42.

Thus, in the first defrosting mode, the first port 21 and the second port 22 of the first reversing assembly 2 are kept in conduction, the third port 23 and the fourth port 24 are kept in conduction, the first port 51 and the third port 53 of the second reversing assembly 5 are controlled to be in conduction, the first throttle 43 is controlled to throttle, the second throttle 44 is controlled to be fully opened, and the first on-off valve 61 is controlled to be closed. At this time, the flow direction of the refrigerant in the first defrost mode may be: the high-temperature and high-pressure gaseous refrigerant discharged from the discharge port 12 of the compressor 1 flows to the first reversing assembly 2 and the second reversing assembly 5, respectively. The refrigerant flowing toward the first reversing assembly 2 flows into the first reversing assembly 2 through the first valve port 21 and flows out of the first reversing assembly 2 from the second valve port 22. The refrigerant flowing out of the second valve port 22 flows into the indoor heat exchanger 3, and the high-temperature and high-pressure gaseous refrigerant exchanges heat with the Cheng Gaowen high-pressure two-phase refrigerant in the indoor heat exchanger 3. Flows out of the indoor heat exchanger 3 to the first throttle valve 43, throttles down by the first throttle valve 43, and flows to the first portion 41. The refrigerant flowing toward the second reversing element 5 flows into the second reversing element 5 through the first port 51 and out of the second reversing element 5 through the third port 53. The refrigerant flowing out of the third port 53 flows into the second portion 42, so that the high-temperature and high-pressure gaseous refrigerant discharged from the compressor 1 is cooled in the second portion 42 to a high-pressure and medium-temperature liquid refrigerant, and the second portion 42 is defrosted by using the latent heat of the refrigerant. The refrigerant flowing out of the second portion 42 flows through the second throttle valve 44 to the first throttle valve 43, throttled down by the first throttle valve 43, and then flows to the first portion 41. Finally, the refrigerant flowing out of the first portion 41 flows back to the suction port 11 of the compressor 1 through the third port 23 and the fourth port 24.

s4: if the air conditioning system 100 meets the first defrosting mode end condition, the third port 53 of the second reversing assembly 5 is controlled to be communicated with the second port 52, the first throttle valve 43 is controlled to be fully closed, the second throttle valve 44 is controlled to throttle, the first on-off valve 61 is opened, and the air conditioning system 100 is controlled to exit the first defrosting mode and operate in the second defrosting mode, and the first part 41 is defrosted in the second defrosting mode.

Thus, in the second defrosting mode, the first valve port 21 and the second valve port 22 of the first reversing assembly 2 are kept in conduction, the third valve port 23 and the fourth valve port 24 are kept in conduction, the third port 53 and the second port 52 of the second reversing assembly 5 are kept in conduction, the first throttle valve 43 is controlled to be fully closed, the second throttle valve 44 is throttled, and the first on-off valve 61 is opened. At this time, the flow direction of the refrigerant in the second defrost mode may be: the high-temperature and high-pressure gaseous refrigerant discharged from the discharge port 12 of the compressor 1 flows into the first reversing unit 2 and the defrost branch 6, respectively, and the high-temperature and high-pressure gaseous refrigerant flowing into the defrost branch 6 flows into the first portion 41, and frost of the first portion 41 is removed by sensible heat of the high-temperature and high-pressure gaseous refrigerant discharged from the compressor 1. The refrigerant flowing toward the first reversing assembly 2 flows into the first reversing assembly 2 through the first valve port 21 and flows out of the first reversing assembly 2 from the second valve port 22. The refrigerant flowing out of the second valve port 22 flows into the indoor heat exchanger 3, is changed into a high-temperature and high-pressure two-phase refrigerant after heat exchange in the indoor heat exchanger 3, then flows out of the indoor heat exchanger 3 and flows into the second throttle valve 44, the refrigerant throttled and depressurized by the second throttle valve 44 flows into the second part 42, is evaporated into a low-temperature and low-pressure gaseous refrigerant in the second part 42, and then flows out of the second part 42. Finally, the refrigerant flowing out of the second portion 42 flows back to the suction port 11 of the compressor 1 through the third port 53 and the second port 52 in sequence, and the refrigerant flowing out of the first portion 41 flows back to the suction port 11 of the compressor 1 through the third port 23 and the fourth port 24 in sequence.

s6: if the second defrosting mode end condition is satisfied, the first throttle valve 43 is controlled to throttle, the first on-off valve 61 is closed to exit the second defrosting mode, and the heating mode is operated.

Therefore, when the heating mode is switched to the first defrosting mode and the second defrosting mode for defrosting the first portion 41 and the second portion 42, the first reversing assembly 2 is not reversed all the time, so that the power consumption of the air conditioning system 100 can be reduced, the air conditioning system 100 can realize uninterrupted heating, the indoor can be kept in a high-temperature state all the time, and the comfort of a user can be improved. Meanwhile, the second defrosting mode utilizes the high-temperature and high-pressure gaseous refrigerant discharged from the exhaust port 12 of the compressor 1 to defrost the first part 41, and the defrosting effect is remarkable. The first defrosting mode uses the second reversing component 5 to reverse a part of refrigerant at the exhaust port 12 of the bypass compressor 1 to the second part 42, and enables the refrigerant to be cooled into a high-temperature medium-pressure gaseous refrigerant in the second part 42, and enables the refrigerant flowing out of the second part 42 to flow to the first part 41, so that the second part 42 can be defrosted by utilizing latent heat of the refrigerant, and the advantage of waste heat defrosting and sensible heat defrosting can be utilized by a defrosting mode combining low-pressure sensible heat and high-pressure waste heat, meanwhile, the problems of serious waste heat defrosting capability, poor sensible heat defrosting reliability and narrow applicable working conditions can be avoided, and the reliability and stability of the operation of the air conditioning system 100 can be improved.

In some embodiments, the second portion 42 is located directly above the first portion 41, and in the first defrost mode, the second portion 42 is defrosted and in the second defrost mode, the first portion 41 is defrosted. Therefore, when the second portion 42 is located directly above the first portion 41, during the defrosting of the outdoor heat exchanger assembly 4, by defrosting the second portion 42 first, and defrosting the first portion 41 after the defrosting of the second portion 42 is completed, it is beneficial to ensure the defrosting effect of the outdoor heat exchanger assembly 4, and the problem that the defrosting effect of the first portion 41 is deteriorated because the defrosting of the first portion 41 is performed first and then the defrosting of the second portion 42 is performed is prevented, and when the defrosted water of the second portion 42 drops onto the first portion 41 as an evaporator, the first portion 41 is frozen.

In some embodiments, in order to enhance the evaporation capacity of the second portion 42, the outdoor fan 45 is disposed at a side of the second portion 42 away from the first portion 41, and if the air conditioning system 100 satisfies the first defrosting mode end condition, the outdoor fan 45 is controlled to be turned on so that air can be supplied to the second portion 42 during defrosting of the first portion 41 in step S4. Thus, after the defrosting of the second portion 42 is completed, the outdoor fan 45 is turned on to improve the evaporation capacity of the second portion 42, and further to improve the suction pressure of the compressor 1, so that the indoor side can be quickly discharged after the defrosting of the air conditioning system 100 is completed, which is beneficial to improving the use experience of users.

In some embodiments, the second defrost mode end condition is: the temperature Tg1 at the first end of the first portion 41 is greater than or equal to Tgo1 and is maintained for a first predetermined time. Therefore, when the first defrosting mode end condition is met, the first defrosting mode can be timely exited, so that the intelligent degree and reliability of the air conditioning system 100 can be improved.

Illustratively, in the embodiment depicted in FIG. 10, a first portion temperature sensor 411 may be provided at the first end of the first portion 41 for acquiring the temperature Tg1 at the first end of the second portion 42.

In some embodiments, the first defrost mode end condition is: the temperature Tg2 at the second end of the second portion 42 is greater than or equal to Tgo2 for a second predetermined time. Therefore, the second defrosting mode can be timely exited when the second defrosting mode ending condition is met, so that the intelligent degree and the reliability of the air conditioning system 100 are improved.

A fourth defrosting control method of the air conditioning system 100 of the embodiment of the present application is explained below.

Referring to fig. 12, fig. 12 is a flowchart of a fourth defrosting control method of an air conditioning system according to an embodiment of the present application. Among them, the fourth defrosting control method is a defrosting control method of the air conditioning system 100 based on the first section 41 being located directly above the second section 42.

The defrosting control method of the air conditioning system 100 includes the steps of:

s4: if the air conditioning system 100 satisfies the first defrost mode end condition, the second port 52 of the second reversing assembly 5 is controlled to be connected to the third port 53, the second throttle valve 44 is fully closed, and the first on-off valve 61 is opened to control the air conditioning system 100 to exit the first defrost mode, and the second defrost mode is operated, in which the first portion 41 is defrosted.

Thus, in the second defrosting mode, the first port 21 and the second port 22 of the first reversing assembly 2 are kept in conduction, the third port 23 and the fourth port 24 are kept in conduction, the second port 52 and the third port 53 of the second reversing assembly 5 are kept in conduction, the first throttle 43 is throttled, the second throttle 44 is fully closed, and the first on-off valve 61 is opened. At this time, the flow direction of the refrigerant in the second defrost mode may be: the high-temperature and high-pressure gaseous refrigerant discharged from the discharge port 12 of the compressor 1 flows into the first reversing assembly 2 and the defrost branch 6, respectively, and the high-temperature and high-pressure gaseous refrigerant flowing into the defrost branch 6 flows into the first portion 41. The refrigerant flowing toward the first reversing assembly 2 flows into the first reversing assembly 2 through the first valve port 21 and flows out of the first reversing assembly 2 from the second valve port 22. The refrigerant flowing out of the second valve port 22 flows into the indoor heat exchanger 3, is changed into a high-temperature and high-pressure two-phase refrigerant after heat exchange in the indoor heat exchanger 3, flows out of the indoor heat exchanger 3 and flows into the first throttle valve 43, and the refrigerant throttled and depressurized by the first throttle valve 43 flows into the first portion 41. The high-temperature and high-pressure gaseous refrigerant flowing out of the defrosting branch 6 and the low-temperature and low-pressure two-phase refrigerant flowing out of the first throttle valve 43 flow into the first portion 41, and frost in the first portion 41 is removed. The refrigerant flowing out of the first portion 41 flows back to the suction port 11 of the compressor 1 through the third port 23 and the fourth port 24.

s6: if the second defrosting mode end condition is satisfied, the second throttle valve 44 is controlled to throttle, the first on-off valve 61 is closed to exit the second defrosting mode, and the heating mode is operated.

Therefore, when the heating mode is switched to the first defrosting mode and the second defrosting mode for defrosting the first portion 41 and the second portion 42, the first reversing assembly 2 is not reversed all the time, so that the power consumption of the air conditioning system 100 can be reduced, the air conditioning system 100 can realize uninterrupted heating, the indoor can be kept in a high-temperature state all the time, and the comfort of a user can be improved. Meanwhile, in the first defrosting mode, a part of refrigerant at the exhaust port 12 of the bypass compressor 1 is commutated to the second part 42 by using the second commutating component 5, the refrigerant is cooled to be a high-temperature medium-pressure gaseous refrigerant in the second part 42, and the refrigerant flowing out of the second part 42 can flow to the first part 41, so that the second part 42 can be defrosted by using latent heat of the refrigerant, and the advantages of waste heat defrosting and sensible heat defrosting can be utilized by using a defrosting mode combining low-pressure sensible heat and high-pressure waste heat, and the problems of serious waste heat defrosting capacity, poor sensible heat defrosting reliability and narrow applicable working conditions can be avoided, thereby being beneficial to improving the reliability and stability of the operation of the air conditioning system 100. Further, since the first portion 41 is located directly above the second portion 42, the second portion 42 is not used as an evaporator by closing the second throttle valve 44 entirely when the first portion 41 is defrosted, and thus, the problem of freezing of the second portion 42 due to the fact that the defrosted water of the first portion 41 drops onto the second portion 4 when the second portion 42 is used as an evaporator during defrosting of the first portion 41 can be avoided.

Referring to fig. 13, fig. 13 is a flowchart of a fifth defrosting control method of an air conditioning system according to an embodiment of the present application. The defrosting control method of the air conditioning system 100 in step S6 specifically includes the following steps:

s61: after the air conditioning system 100 exits the second defrost mode, the air conditioning system 100 is controlled to operate in a heating start mode. Wherein, when the air conditioning system 100 is in the heating start mode, the second port 52 is controlled to be conducted with the third port 53; the first throttle valve 43 throttles, the second throttle valve 44 throttles, the first on-off valve 61 closes, and the heating device 73 opens.

Thereby, in the heating start mode, the second port 52 and the third port 53 are kept conductive; the first throttle valve 43 throttles, the second throttle valve 44 throttles, the first on-off valve 61 closes, and the heating device 73 opens.

S62: judging whether the air conditioning system 100 satisfies a heating start mode end condition; s63: if the air conditioning system 100 meets the heating start mode end condition, the heating device 73 is controlled to be turned off so as to control the air conditioning system 100 to exit the heating start mode and operate the heating mode;

therefore, the heating device 73 heats the gas-liquid separator 7, so that the liquid refrigerant accumulated in the gas-liquid separator 7 can be evaporated, the pressure and the temperature of the gaseous refrigerant at the gas outlet 72 of the gas-liquid separator 7 can be increased, the exhaust pressure and the exhaust temperature of the compressor 1 can be increased, the high-low pressure differential pressure establishment speed can be increased after the air conditioning system 100 exits the second defrosting mode, the influence on the heating cycle capacity of the air conditioning system 100 can be avoided, and the heating capacity of the air conditioning system 100 can be improved.

In some embodiments, the exit conditions for the heating start mode are: the temperature Tg3 of the indoor heat exchanger is more than or equal to Tgo3 and lasts for a third preset time. Therefore, when the exit condition of the heating start mode is met, the heating start mode can be exited in time, and the intelligent degree and the reliability of the air conditioning system are improved.

In some embodiments, the air conditioning system 100 further includes an indoor fan 33, and the indoor fan 33 may be located at one side of the indoor heat exchanger 3. Wherein the indoor fan 33 may be turned off when the air conditioning system 100 operates in the first defrost mode and the second defrost mode. This arrangement is advantageous in enhancing the defrosting effect of the air conditioning system 100.

In some embodiments, 10 ℃ or less than Tgo3 or less than 40 ℃. For example, tgo may be 10 ℃, 11 ℃, 12 ℃, 13 ℃, 14 ℃, 15 ℃, 16 ℃, 20 ℃, 25 ℃, 30 ℃, 35 ℃, 40 ℃, or the like.

In some embodiments, 5 seconds or less and the third preset time or less than 30 seconds. For example, the third preset time may take a value of 5 seconds, 10 seconds, 15 seconds, 20 seconds, 25 seconds, 30 seconds, or the like.

The foregoing is merely illustrative of the present invention, and the present invention is not limited thereto, and any person skilled in the art will readily recognize that variations or substitutions are within the scope of the present invention. Therefore, the protection scope of the present invention shall be subject to the protection scope of the claims.

Claims

1. A defrosting control method of an air conditioning system, characterized in that the air conditioning system comprises:

the first defrosting flow path comprises an exhaust port of the compressor, a defrosting branch, a first part of the outdoor heat exchanger and an air suction port of the compressor which are sequentially connected, and a first on-off valve is connected in series on the defrosting branch;

the second defrosting flow path comprises an exhaust port, a second part of the outdoor heat exchanger, a second throttle valve, a first part of the outdoor heat exchanger and an air suction port of the compressor which are connected in sequence;

the defrosting control method comprises the following steps:

2. The defrosting control method of an air conditioning system according to claim 1, wherein in the first defrosting mode, the first portion is defrosted, and in the second defrosting mode, the second portion is defrosted.

3. The defrosting control method of an air conditioning system according to claim 1, wherein the first defrosting mode end condition is: the air side temperature Tg1 of the first part is above a first preset temperature Tgo1 and lasts for a first preset time; and/or, the second defrosting mode end condition is: the liquid side temperature Tg2 of the second portion is above a second preset temperature Tgo2 for a second preset time.

4. The defrosting control method of an air conditioning system according to claim 1, wherein in the first defrosting mode, the second portion is defrosted, and in the second defrosting mode, the first portion is defrosted.

5. The defrosting control method of an air conditioning system according to claim 4, wherein the first defrosting mode end condition is: the liquid side temperature Tg2 of the second part is above a second preset temperature Tgo2 and lasts for a second preset time; and/or, the second defrosting mode end condition is: the gas side temperature Tg1 of the first portion is above a first preset temperature Tgo1 for a first preset time.

6. The defrosting control method of an air conditioning system according to claim 1, characterized in that the air conditioning system further comprises: a gas-liquid separator having a liquid inlet and a gas outlet, and a heating device for heating the gas-liquid separator; the method further comprises the steps of:

after the air conditioning system exits the second defrosting mode, controlling the air conditioning system to operate in a heating starting mode;

judging whether the air conditioning system meets the heating start mode ending condition or not;

If yes, controlling the air conditioning system to exit the heating start mode and operating the heating mode;

in a heating starting mode, the second throttle valve is throttled, the first on-off valve is closed, and the heating device is opened;

in heating mode, the heating device is turned off.

7. The defrosting control method of an air conditioning system according to claim 4, wherein the heating start mode exit condition is: the temperature Tg3 of the indoor heat exchanger is more than or equal to Tgo3 and lasts for a third preset time.

8. The defrosting control method of an air conditioning system according to claim 1, characterized in that the air conditioning system further comprises:

the first reversing assembly is provided with first to fourth valve ports, the first valve port is connected with the exhaust port, the fourth valve port is connected with the air suction port, the first valve port is in reversing conduction with one of the second valve port and the third valve port, and the fourth valve port is in reversing conduction with the other of the second valve port and the third valve port;

the second reversing component is provided with first to third ports, the first port is connected with the exhaust port, the second port is connected with the air suction port, and the third port is in reversing conduction with one of the first port and the second port.

9. The defrost control method of an air conditioning system according to claim 8, wherein a first end of said indoor heat exchanger is connected to said second valve port; the first end of the first part of the outdoor heat exchanger component is connected with the third valve port, the first end of the second part is connected with the third port, a first throttle valve is connected between the second end of the first part and the second end of the indoor heat exchanger, and the second throttle valve is located between the second end of the second part and the second end of the indoor heat exchanger.

10. The defrost control method of an air conditioning system according to claim 8, wherein the first reversing assembly is a four-way reversing valve; and/or, the second reversing component is a three-way reversing valve or a four-way reversing valve, wherein when the second reversing component is a four-way reversing valve, the second reversing component further comprises a fourth port, the fourth port is cut off, and the fourth port is in reversing conduction with the other one of the first port and the second port.