CN114111089B

CN114111089B - Air conditioning system and control method thereof

Info

Publication number: CN114111089B
Application number: CN202110183002.9A
Authority: CN
Inventors: 马熙华; 王命仁; 谭志军; 王国春
Original assignee: Midea Group Co Ltd; GD Midea Heating and Ventilating Equipment Co Ltd
Current assignee: Midea Group Co Ltd; GD Midea Heating and Ventilating Equipment Co Ltd
Priority date: 2020-08-26
Filing date: 2021-02-08
Publication date: 2023-01-03
Anticipated expiration: 2041-02-08
Also published as: CN114111089A

Abstract

The application discloses an air conditioning system and a control method thereof, wherein the control method comprises the following steps: opening the first expansion valve and the second expansion valve to enable the first refrigerant flow of the first heat exchange channel and the second refrigerant flow of the second heat exchange channel to exchange heat, and enabling the heat storage device to store heat; detecting the outlet temperature of the outdoor heat exchanger in response to the refrigeration mode, and calculating a first difference value between the outlet temperature of the outdoor heat exchanger and the saturation temperature of the refrigerant flow; comparing the first difference value with a preset temperature; and in response to the first difference value being larger than the preset temperature, closing the opening degree of the first expansion valve so as to enable the second refrigerant flow of the second heat exchange channel to exchange heat with the heat storage device. According to the scheme, the second refrigerant flow of the second heat exchange channel exchanges heat with the heat storage device to gasify the second refrigerant flow, and the gasified second refrigerant flow carries out enhanced vapor injection on the compressor, so that the heating capacity of the air-conditioning system is improved.

Description

Air conditioning system and control method thereof

Technical Field

The present disclosure relates to air conditioning technologies, and in particular, to an air conditioning system and a control method thereof.

Background

The air conditioning system includes an economizer provided with a main circuit and a sub-circuit, and a refrigerant of the sub-circuit evaporates to absorb heat so that the refrigerant of the main circuit is supercooled. When the opening degree of the expansion valve of the economizer main circuit is reduced, the refrigerant of the sub circuit cannot be completely vaporized.

Disclosure of Invention

The present application provides at least an air conditioning system and a control method thereof.

The first aspect of the present application provides a control method, which is applied to an air conditioning system, the air conditioning system at least comprises a compressor, a four-way valve, an outdoor heat exchanger, an indoor heat exchanger, a first expansion valve, a second expansion valve, a third expansion valve and an auxiliary heat exchanger, the compressor is provided with a heat storage device, a first heat exchange channel and a second heat exchange channel, the inlet of the first heat exchange channel is connected to the third expansion valve and between the outdoor heat exchangers through the first expansion valve, the outlet of the first heat exchange channel is connected to the third expansion valve and between the indoor heat exchangers, the inlet of the second heat exchange channel is connected to the third expansion valve and between the indoor heat exchangers through the second expansion valve, the outlet of the second heat exchange channel is connected to the compressor, and the control method comprises the following steps:

opening the first expansion valve and the second expansion valve to enable the first refrigerant flow of the first heat exchange channel and the second refrigerant flow of the second heat exchange channel to exchange heat, and enabling the heat storage device to store heat;

responding to a refrigeration mode, detecting the outlet temperature of the outdoor heat exchanger, calculating a first difference value between the outlet temperature of the outdoor heat exchanger and the saturation temperature of the refrigerant flow, and comparing the first difference value with a preset temperature;

and in response to the first difference being greater than the preset temperature, closing the opening of the first expansion valve to enable the second refrigerant flow of the second heat exchange channel to exchange heat with the heat storage device.

The second aspect of the present application provides an air conditioning system, including compressor, cross valve, outdoor heat exchanger, indoor heat exchanger, first expansion valve, second expansion valve, third expansion valve and auxiliary heat exchanger at least, the compressor passes through the cross valve is in outdoor heat exchanger with provide the refrigerant stream of circulation flow between the indoor heat exchanger, the third expansion valve is connected to indoor heat exchanger with between the outdoor heat exchanger, auxiliary heat exchanger is provided with heat accumulation device, first heat transfer passageway and second heat transfer passageway, the entry of first heat transfer passageway passes through first expansion valve is connected to the third expansion valve with between the outdoor heat exchanger, the exit linkage of first heat transfer passageway to the third expansion valve with between the indoor heat exchanger, the entry of second heat transfer passageway passes through the second expansion valve is connected to the third expansion valve with between the indoor heat exchanger, the exit linkage of second heat transfer passageway the compressor, wherein air conditioning system is used for realizing foretell control method.

The beneficial effect of this application is: the control method of the application comprises the following steps: opening the first expansion valve and the second expansion valve to enable the first refrigerant flow of the first heat exchange channel and the second refrigerant flow of the second heat exchange channel to exchange heat, and enabling the heat storage device to store heat; and in response to the first difference value being larger than the preset temperature, closing the opening of the first expansion valve to enable the second refrigerant flow of the second heat exchange channel to exchange heat with the heat storage device, wherein the second refrigerant flow of the second heat exchange channel absorbs heat from the heat storage module to enable the second refrigerant flow to be gasified, and the gasified second refrigerant flow performs enhanced vapor injection on the compressor to improve the heating capacity of the air conditioning system.

It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the application.

Drawings

The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments consistent with the present application and, together with the description, serve to explain the principles of the application.

Fig. 1 is a schematic structural diagram of an air conditioning system in an embodiment of the present application;

FIG. 2 is a schematic structural diagram of a heat exchange body of the heat exchanger of FIG. 1;

FIG. 3 is a schematic structural view of the single-layer microchannel and the multi-layer microchannel of FIG. 2;

FIG. 4 is a schematic block diagram of an embodiment of a manifold assembly of the heat exchanger of FIG. 1;

FIG. 5 is a schematic structural view of another embodiment of a header assembly of the heat exchanger of FIG. 1;

FIG. 6 is a schematic structural view of yet another embodiment of a header assembly of the heat exchanger of FIG. 1;

FIG. 7 is a schematic structural diagram of a heat exchange body of a heat exchanger according to another embodiment of the present application;

FIG. 8 is a perspective view of the first tube of FIG. 7;

FIG. 9 is a schematic structural diagram of a heat exchange body of a heat exchanger according to another embodiment of the present application;

FIG. 10 is a schematic diagram of the heat exchanger of FIG. 9;

fig. 11 is a schematic perspective view of an outdoor unit of an air conditioner according to an embodiment of the present application;

FIG. 12 is an enlarged view of region A of FIG. 11;

FIG. 13 is a schematic diagram of a framework of an air conditioning system according to an embodiment of the present application;

fig. 14 is a flow chart diagram of a control method applied to the air conditioning system of fig. 13;

FIG. 15 is a flowchart illustrating an embodiment of step S142 in FIG. 14;

FIG. 16 is a schematic flow chart illustrating another embodiment of step S142 in FIG. 14;

FIG. 17 is a schematic block diagram of an air conditioning system according to another embodiment of the present application;

fig. 18 is a flow chart diagram of a control method applied to the air conditioning system of fig. 17;

FIG. 19 is a flowchart illustrating an embodiment of step S182 of FIG. 18;

FIG. 20 is a flowchart illustrating an embodiment of step S184 in FIG. 18;

FIG. 21 is a schematic diagram of a framework of an air conditioning system according to yet another embodiment of the present application;

fig. 22 is a flow chart diagram of a control method applied to the air conditioning system of fig. 21;

FIG. 23 is a schematic flow chart diagram illustrating one embodiment of the control method of FIG. 22;

FIG. 24 is a schematic diagram of a framework of an air conditioning system according to yet another embodiment of the present application;

FIG. 25 is a schematic structural view of an embodiment of the thermal storage device of FIG. 24;

fig. 26 is a schematic structural view of another embodiment of the thermal storage device of fig. 24;

fig. 27 is a flow chart diagram of a control method applied to the air conditioning system of fig. 26;

FIG. 28 is a schematic flow chart diagram illustrating one embodiment of the control method of FIG. 27;

FIG. 29 is a schematic diagram of a framework of an air conditioning system according to yet another embodiment of the present application;

fig. 30 is a flow chart diagram of a control method applied to the air conditioning system of fig. 29;

FIG. 31 is a schematic flow chart diagram illustrating one embodiment of the control method of FIG. 30;

FIG. 32 is a flow chart illustrating another embodiment of the control method of FIG. 30.

Detailed Description

The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application, and it is obvious that the described embodiments are only a part of the embodiments of the present application, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present application.

Reference herein to "an embodiment" means that a particular feature, structure, or characteristic described in connection with the embodiment can be included in at least one embodiment of the application. The appearances of the phrase in various places in the specification are not necessarily all referring to the same embodiment, nor are separate or alternative embodiments mutually exclusive of other embodiments. It is explicitly and implicitly understood by one skilled in the art that the embodiments described herein can be combined with other embodiments.

Referring to fig. 1, fig. 1 is a schematic structural diagram of an air conditioning system according to an embodiment of the present application. As shown in fig. 1, the air conditioning system 1 mainly includes a compressor 2, a four-way valve 3, an outdoor heat exchanger 4, an indoor heat exchanger 5, a heat exchanger 6, an expansion valve 12, and an expansion valve 13. The expansion valve 13 and the heat exchanger 6 are disposed between the outdoor heat exchanger 4 and the indoor heat exchanger 5, and the compressor 2 provides a refrigerant flow circulating between the outdoor heat exchanger 4 and the indoor heat exchanger 5 through the four-way valve 3.

The heat exchanger 6 includes a first heat exchange path 610 and a second heat exchange path 611, a first end of the first heat exchange path 610 is connected to the outdoor heat exchanger 4 through an expansion valve 13, a second end of the first heat exchange path 610 is connected to the indoor heat exchanger 5, a first end of the second heat exchange path 611 is connected to a second end of the first heat exchange path 610 through an expansion valve 12, and a second end of the second heat exchange path 611 is connected to the suction port 22 of the compressor 2.

When the air conditioning system 1 is in the cooling mode, the path of the refrigerant flow is as follows:

the exhaust port 21 of the compressor 2, the connection port 31 of the four-way valve 3, the connection port 32 of the four-way valve 3, the outdoor heat exchanger 4, the heat exchanger 6, the indoor heat exchanger 5, the connection port 33 of the four-way valve 3, the connection port 34 of the four-way valve 3, and the suction port 22 of the compressor 2.

The path (main path) of the refrigerant flow of the first heat exchange channel 610 is: a first end of the first heat exchange channel 610-a second end of the first heat exchange channel 610-the indoor heat exchanger 5. The path (sub path) of the refrigerant flow of the second heat exchange channel 611 is: the second end of the first heat exchange passage 610-the expansion valve 12-the first end of the second heat exchange passage 611-the second end of the second heat exchange passage 611-the suction port 22 of the compressor 2.

For example, the operating principle of the air conditioning system 1 at this time is: the outdoor heat exchanger 4 serves as a condenser, and outputs a medium-pressure medium-temperature refrigerant flow (the temperature may be 40 ° or less) through the expansion valve 13, the refrigerant flow of the first heat exchange channel 610 is the medium-pressure medium-temperature refrigerant flow, the expansion valve 12 converts the medium-pressure medium-temperature refrigerant flow into a low-pressure low-temperature refrigerant flow (the temperature may be 10 ° or less, and a gas-liquid two-phase refrigerant flow), and the refrigerant flow of the second heat exchange channel 611 is the low-pressure low-temperature refrigerant flow. The low-pressure low-temperature refrigerant flow of the second heat exchange channel 611 absorbs heat from the medium-pressure medium-temperature refrigerant flow of the first heat exchange channel 610, and further the refrigerant flow of the second heat exchange channel 611 is gasified, so that the refrigerant flow of the first heat exchange channel 610 is further supercooled. The gasified refrigerant flow of the second heat exchange channel 611 performs enhanced vapor injection on the compressor 2, so as to improve the refrigerating capacity of the air conditioning system 1.

The expansion valve 12 is used as a throttling component of the second heat exchange channel 611, and adjusts the flow rate of the refrigerant flow of the second heat exchange channel 611. The refrigerant flow of the first heat exchange channel 610 and the refrigerant flow of the second heat exchange channel 611 perform heat exchange to realize supercooling of the refrigerant flow of the first heat exchange channel 610. Therefore, the heat exchanger 6 can be used as an economizer of the air conditioning system 1, and the supercooling degree is improved, so that the heat exchange efficiency of the air conditioning system 1 is improved.

Further, as understood by those skilled in the art, in the heating mode, the connection port 31 of the four-way valve 3 is connected to the connection port 33, and the connection port 32 of the four-way valve 3 is connected to the connection port 34. The refrigerant flow output from the compressor 2 through the discharge port 21 flows from the indoor heat exchanger 5 to the outdoor heat exchanger 4, and the indoor heat exchanger 5 serves as a condenser. At this time, the refrigerant flow output from the indoor heat exchanger 5 is divided into two paths, one of which flows into the first heat exchange channel 610 (main path), and the other of which flows into the second heat exchange channel 611 (auxiliary path) via the expansion valve 12. The refrigerant flow of the second heat exchange channel 611 can also realize supercooling of the refrigerant flow of the first heat exchange channel 610, and the refrigerant flow flowing through the second heat exchange channel 611 performs air supplement and enthalpy increase on the compressor 2, so that the heating capacity of the air conditioner is improved.

The present application further optimizes the following aspects based on the overall structure of the air conditioning system 1 described above:

1. micro-channel heat exchanger

As shown in fig. 2, the heat exchanger 6 comprises a heat exchange body 61, the heat exchange body 61 is provided with a plurality of microchannels 612, and the plurality of microchannels 612 are divided into a first microchannel and a second microchannel, wherein the first microchannel serves as a first heat exchange channel 610 of the heat exchanger 6, and the second microchannel serves as a second heat exchange channel 611 of the heat exchanger 6. Thus, first microchannel 610 is given the same reference number as first heat exchange channel 610 and second microchannel 611 is given the same reference number as second heat exchange channel 611.

Heat exchange body 61 may comprise a single plate body 613, plate body 613 is provided with a plurality of microchannels 612, and plurality of microchannels 612 of plate body 613 may be divided into first microchannels 610 and second microchannels 611 arranged alternately, and extending direction D1 of first microchannels 610 and extending direction D2 of second microchannels 611 are parallel to each other, for example, extending direction D1 of first microchannels 610 is the same as extending direction D2 of second microchannels 611. The board body 613 may be a flat pipe so that a heat dissipation element or an electronic element may be disposed on the board body 613. In other embodiments, the plate body 613 may also be a carrier with a cross section of other shapes, such as a cylinder, a rectangular parallelepiped, a cube, and the like. In other embodiments, as described below, the heat exchange body 61 may also include at least two plates disposed on top of each other or two tubes nested within each other.

The cross-sectional shape of each micro channel 612 perpendicular to its extension direction may be rectangular, with each micro channel 612 having a side of 0.5mm to 3mm. The thickness between each micro channel 612 and the surface of plate body 613 and between micro channels 612 is 0.2mm-0.5mm so that micro channels 612 meet the requirements of pressure resistance and heat transfer performance. In other embodiments, the cross-sectional shape of the micro-channels 612 may be other shapes, such as circular, triangular, trapezoidal, elliptical, or irregular.

For example, in the cooling mode of the air conditioning system shown in fig. 1, a first refrigerant flow (i.e., a medium-pressure medium-temperature refrigerant flow) flows through the first microchannel 610, a second refrigerant flow (i.e., a low-pressure low-temperature refrigerant flow) flows through the second microchannel 611, the first refrigerant flow may be a liquid-phase refrigerant flow, and the second refrigerant flow may be a gas-liquid two-phase refrigerant flow. The second refrigerant stream absorbs heat from the first refrigerant stream of the first microchannel 610 during flow along the second microchannel 611 and is further vaporized to further subcool the first refrigerant stream.

It should be noted that the heat exchanger based on the micro-channel structure described above and below is not limited to the application scenario shown in fig. 1, and thus the first micro-channel 610 and the second micro-channel 611 and the "first" and "second" in the first refrigerant flow and the second refrigerant flow are only used for distinguishing different micro-channels and refrigerant flows, and should not be considered as limiting the specific application of the micro-channels and refrigerant flows. For example, in other embodiments or operation modes, the first refrigerant flow flowing through the first microchannel 610 absorbs heat of the second refrigerant flow of the second microchannel 611, and the states of the first refrigerant flow and the second refrigerant flow are not limited to the liquid phase or the gas-liquid two-phase as defined above.

As shown in fig. 1, a flow direction A1 of the first refrigerant flow is opposite to a flow direction A2 of the second refrigerant flow, so that a temperature difference between the temperature of the first refrigerant flow and the temperature of the second refrigerant flow is large, and heat exchange efficiency of the first refrigerant flow and the second refrigerant flow is improved.

Alternatively, the flow direction A1 of the first refrigerant flow may be the same as or perpendicular to the flow direction A2 of the second refrigerant flow.

Alternatively, the heat exchange body 61 may comprise at least two sets of first microchannels 610 and second microchannels 611, the at least two sets of first microchannels 610 and second microchannels 611 being spaced apart from each other in a direction perpendicular to the extension direction D1, as shown in fig. 2, the perpendicular direction being a width direction of the plate body 613, and in other embodiments, the perpendicular direction may be a thickness direction of the plate body 613. For example, a first predetermined number of micro-channels in the plurality of micro-channels 612 are divided into first micro-channels 610, a second predetermined number of micro-channels in the plurality of micro-channels 612 are divided into second micro-channels 611, and the plurality of sets of first micro-channels 610 and the plurality of sets of second micro-channels 611 are arranged alternately in sequence, that is, the second micro-channels 611 are arranged between the two sets of first micro-channels 610, and the first micro-channels 610 are arranged between the two sets of second micro-channels 611, so that the at least two sets of first micro-channels 610 and the second micro-channels 611 are arranged at intervals to form the heat exchanger 6 in which the first micro-channels 610 and the second micro-channels 611 are arranged alternately, as shown in fig. 2. The first and second preset numbers may be equal, for example 3; in other embodiments, the first predetermined number and the second predetermined number may not be equal, for example, the first predetermined number is 3 and the second predetermined number is 2.

Alternatively, the first predetermined number and the second predetermined number may be 1, one microchannel in the plurality of microchannels 612 is the first microchannel 610, and one microchannel disposed adjacent to the first microchannel 610 is the second microchannel 611.

Taking the heat exchange body 61 provided with 10 × 10 microchannels 612 as an example, the cross-sectional area of the heat exchange body 61 is the same as that of the conventional channel, and refrigerant streams of the same mass and flow rate respectively flow through the 10 × 10 microchannels 612 and the conventional channel. Each microchannel 612 has a characteristic length Dh of 1/10 that of a conventional channel, where the pressure drop is related to L/(Dh) ² ) In proportion, maintaining the same pressure drop, the length L of the micro-channels 612 is 1/100 of the length of the conventional channels.

The effective heat exchange area of the microchannels 612 is 1/10 of the effective heat exchange area of the conventional channels. Based on the formula: characteristic length = constant, and the heat exchange coefficient of the micro channel 612 is 10 times that of the conventional channel; based on the formula: the heat exchange quantity = heat exchange coefficient × heat exchange area, and the heat exchange quantity of the obtained micro channel 612 is equal to that of the conventional channel. Thus, 10 x 10 microchannels 612 have a length that is 1/100 the length of a conventional channel, i.e., the same thermal load requirements can be met.

Through the above manner, the heat exchange body 61 is provided with the plurality of first microchannels 610 and the plurality of second microchannels 611, so that the length of the heat exchange body 61 is shortened, and the size of the heat exchanger 6 is further reduced under the condition that the heat exchange amount of the economizer is equal.

As shown in fig. 3, the plurality of microchannels 612 may be arranged as a single layer microchannel or a multi-layer microchannel. In fig. 3, the cross-sectional area of the multi-layer microchannel is 4 times the cross-sectional area of the single-layer microchannel, the length of the single-layer microchannel is 4 times the length of the multi-layer microchannel, refrigerant flows with the same mass and flow rate respectively flow through the single-layer microchannel and the multi-layer microchannel, and the flow rate of the multi-layer microchannel is 1/4 of the flow rate of the single-layer microchannel.

Under the condition that the flow state of the refrigerant flow is laminar flow, the pressure drop of the multilayer micro-channel is 1/16 of that of the single-layer micro-channel, wherein the heat transfer coefficient is the characteristic length = constant, the characteristic length is unchanged, the heat transfer coefficient is unchanged, the heat transfer area of the single-layer micro-channel and the heat transfer area of the multilayer micro-channel are unchanged, and then the heat transfer capacity of the single-layer micro-channel is the same as that of the multilayer micro-channel. Therefore, when the flow velocity of the refrigerant flow is low and the flow state of the refrigerant flow is laminar, the larger the cross-sectional area of the plurality of microchannels 612 is, the shorter the length of the plurality of microchannels 612 is, and the flow resistance loss of the refrigerant flow can be reduced.

Under the condition that the flow state of the refrigerant flow is turbulent flow, the pressure drop of the multilayer microchannel is 1/48 of that of the single-layer microchannel, at the moment, the heat exchange coefficient has a functional relation with the flow speed of the refrigerant flow, and the larger the flow speed of the refrigerant flow is, the larger the heat exchange coefficient is, so that the heat transfer capacity of the single-layer microchannel is higher than that of the multilayer microchannel. As described above, when the heat transfer amount is satisfied, the pressure loss of the refrigerant flow can be reduced as the cross-sectional area of the plurality of microchannels 612 is increased.

1.1 manifold Assembly

As shown in fig. 4, the heat exchanger 6 further includes a header assembly 62, and the header assembly 62 and the heat exchange body 61 are horizontally disposed, for example, the header assembly 62 and the heat exchange body 61 are horizontally disposed. In other embodiments, the header assembly 62 is vertically disposed, i.e., the header assembly 62 is disposed along a direction perpendicular to the horizontal plane (i.e., the direction of gravity), and the heat exchange body 61 is horizontally disposed; or, the collecting pipe assembly 62 is vertically arranged, and the heat exchange main body 61 is vertically arranged; alternatively, the header assembly 62 is horizontally disposed and the heat exchange body 61 is vertically disposed.

The header assembly 62 includes a first header 621 and a second header 622, the first header 621 being provided with a first header passage, the second header 622 being provided with a second header passage. The cross section of the heat exchanger 6 along the flow direction of the refrigerant flow (the first refrigerant flow or the second refrigerant flow) in the heat exchange main body 61 is I-shaped. In other embodiments, the cross-sectional shape of the heat exchanger 6 along the flow direction of the refrigerant flow in the heat exchange body 61 may be L-shaped, U-shaped, G-shaped, or circular.

The first collecting channel is connected to the first microchannel 610 to provide the first refrigerant flow to the first microchannel 610 through the first collecting channel and/or to collect the first refrigerant flow flowing through the first microchannel 610. In this embodiment, the number of the first collecting pipes 621 is two, and the two first collecting pipes 621 are respectively connected to two ends of the first microchannel 610, so as to provide a first refrigerant flow to the first microchannel 610 by using one of the two first collecting pipes 621; and the other of the two first headers 621 is used to collect the first refrigerant flow passing through the first micro-channel 610.

For example, in the air conditioning system shown in fig. 1, the first end of the first microchannel 610 is connected to the outdoor heat exchanger 4 through the expansion valve 13 via one of the two first collecting pipes 621, so as to provide the first refrigerant flow to the first microchannel 610 in the cooling mode; the second end of the first microchannel 610 is connected to the indoor heat exchanger 5 through the other of the two first headers 621 to collect the first refrigerant flow flowing through the first microchannel 610. In the heating mode, since the flow direction of the first refrigerant flow in the first microchannels 610 is opposite, the functions of the two first collecting pipes 621 are interchanged compared to the cooling mode.

The second collecting channel is connected to the second microchannel 611 to supply the second refrigerant flow to the second microchannel 611 through the second collecting channel and/or to collect the second refrigerant flow flowing through the second microchannel 611. In this embodiment, the number of the second collecting pipes 622 is two, and the two second collecting pipes 622 are respectively connected to two ends of the second microchannel 611, so as to provide the second refrigerant flow to the second microchannel 611 by using one of the two second collecting pipes 622; and the second refrigerant flow flowing through the second microchannels 611 is collected by the other of the two second headers 622.

For example, in the air conditioning system shown in fig. 1, the first end of the second microchannel 611 is connected to the expansion valve 12 through one of the two second collecting pipes 622 to provide the second refrigerant flow to the second microchannel 611; the second end of the second microchannel 611 is connected to the suction port 22 of the compressor 2 through the other of the two second collecting pipes 622 to collect the second refrigerant flow passing through the second microchannel 611.

In an embodiment, the same end of the first microchannel 610 in the at least two groups of first microchannels 610 and the same end of the second microchannels 611 in the at least two groups of second microchannels 611 are connected to the same first collecting pipe 621, that is, the same end of all the first microchannels 610 of the heat exchanger 6 is connected to the same first collecting pipe 621, and the same end of all the second microchannels 611 of the heat exchanger 6 is connected to the same second collecting pipe 622, so as to avoid providing a corresponding collecting pipe for each microchannel, and reduce the cost.

In the embodiment shown in fig. 4, since the extending direction D1 of the first microchannel 610 and the extending direction D2 of the second microchannel 611 are parallel to each other, the extending directions of the first header 621 and the second header 622 are parallel to each other. However, in other embodiments, the extending directions of the first header 621 and the second header 622 may be adjusted according to the extending directions of the first microchannel 610 and the second microchannel 611, for example, arranged perpendicular to each other.

1.2 the first collecting pipe and the second collecting pipe are arranged at intervals

As shown in fig. 4, the first header 621 and the second header 622 are disposed at intervals along the extending direction of the heat exchange body 61, the extending direction of the heat exchange body 61 is the same as the extending direction D1 of the first microchannel 610 and the extending direction D2 of the second microchannel 611, the second microchannel 611 penetrates the first header 621 and is connected to the second header 622, wherein the first header 621 is disposed between the second header 622 and the heat exchange body 61, the second microchannel 611 penetrates the first header 621 and is inserted into the second header 622 and is fixed by welding, and the first microchannel 610 is inserted into the first header 621 and is fixed by welding. In other embodiments, the first microchannel 610 may be inserted into the first header 621 after penetrating the second header 622.

The distance between the first header 621 and the second header 622 is R-2r, R being the maximum cross-sectional dimension of the first header 621 in the direction of the separation of the first header 621 and the second header 622. The cross-sectional shapes of the first header 621 and the second header 622 may be both circular, and R is the diameter of the first header 621 or the diameter of the second header 622. In other embodiments, the cross-sectional shapes of the first header 621 and the second header 622 may be configured to be other shapes, such as an oval shape, a square shape, a rectangle shape, or an irregular shape, and when the cross-sectional shapes of the first header 621 and the second header 622 are non-circular, R is the diameter of a circle circumscribed by the first header 621 or the second header 622.

Therefore, the distance between the first header 621 and the second header 622 is set to be large, so that the first header 621 and the second header 622 can be easily welded to the heat exchange body 61. In addition, the second microchannel 611 located between the first header 621 and the second header 622 does not exchange heat with the first microchannel 610, and by setting the distance between the first header 621 and the second header 622 to be smaller, the length of the second microchannel 611 located between the first header 621 and the second header 622 can be reduced, and the heat exchange area of the second microchannel 611 can be increased.

In other embodiments, the first header 621 and the second header 622 may be welded together to reduce the distance between the first header 621 and the second header 622.

In addition, the first microchannel 610 may bypass the second header 622 and then connect to the first header 621, for example, the first microchannel 610 is disposed outside the second header 622 and then connects to the first header 621 after bypassing the second header 622. Alternatively, the second microchannel 611 may bypass the first header 621 and then connect to the second header 622.

1.3 dividing the main header into two headers

As shown in fig. 5, the header assembly 62 includes a header 623 and a flow separator 624, and the flow separator 624 is disposed in the header 623 and is used to divide the header 623 into a first header 621 and a second header 622, i.e., the header 623 is disposed into the first header 621 and the second header 622 separated by the flow separator 624. At this time, as shown in fig. 5, the first microchannels 610 penetrate the side wall of the main header 623 and are inserted into the first header 621, and the second microchannels 611 penetrate the side wall of the main header 623 and the flow dividing plate 624 and are inserted into the second header 622. In other embodiments, the second microchannels 611 extend through the sidewall of the header 623 and are inserted into the second header 622, while the first microchannels 610 extend through the sidewall of the header 623 and the cutoff plate 624 and are inserted into the first header 621. In comparison to the manifold assembly 62 shown in fig. 4: in this embodiment, the function of the first header 621 and the function of the second header 622 are simultaneously realized by one header 623, so that the cost and the volume of the header assembly 62 can be reduced.

In other embodiments, the header 623 may be divided into two first headers 621 or two second headers 622 using the cutoff plate 624. At this time, one end of the first microchannel 610 penetrates the sidewall of the main header 623 and is inserted into one of the first headers 621, and the other end of the first microchannel 610 penetrates the sidewall of the main header 623 and is inserted into the other one of the first headers 621. One first header 621 of the two first headers 621 is configured to provide a first refrigerant flow to the first micro-channel 610, and the other first header 621 of the two first headers 621 is configured to collect the first refrigerant flow flowing through the first micro-channel 610, where the first micro-channel 610 is a U-shaped flow path.

Alternatively, one end of the second microchannel 611 penetrates the sidewall of the main header 623 and is inserted into one of the second headers 622, and the other end of the second microchannel 611 penetrates the sidewall of the main header 623 and the cutoff plate 624 and is inserted into the other of the second headers 622. One of the two second headers 622 is configured to provide a second refrigerant flow to the second microchannel 611, and the other of the two second headers 622 is configured to collect the second refrigerant flow flowing through the second microchannel 611, where the second microchannel 611 is a U-shaped flow path.

1.4 nesting arrangement of first header and second header

As shown in fig. 6, the diameter of the second header 622 is smaller than that of the first header 621, the first header 621 is sleeved outside the second header 622, and the first microchannel 610 penetrates through the sidewall of the first header 621 and is inserted into the first header 621. The second microchannels 611 extend through the sidewalls of the first header 621 and the second header 622 and are inserted into the second header 622. In other embodiments, the second header 622 may be sleeved outside the first header 621, and the second micro-channels 611 penetrate through the sidewall of the second header 622 and are inserted into the second header 622. The first microchannels 610 extend through the sidewalls of the second header 622 and the first header 621 and are inserted into the first header 621.

In comparison to the manifold assembly 62 shown in fig. 4: the nested arrangement allows for a reduction in the volume of the manifold assembly 62.

In other embodiments, it may be that the two first headers 621 are nested within each other, or that the two second headers 622 are nested within each other. At this time, one end of the first microchannel 610 penetrates the sidewall of the outer first header 621 and is inserted into the outer first header 621. The other end of the first microchannel 610 penetrates the sidewalls of the two first headers 621 and is inserted into the inner first header 621. The outer first collecting pipe 621 is configured to provide a first refrigerant flow to the first micro channel 610, and the inner first collecting pipe 621 is configured to collect the first refrigerant flow flowing through the first micro channel 610; or the inner first collecting pipe 621 is used for providing the first refrigerant flow to the first microchannel 610, and the outer first collecting pipe 621 is used for collecting the first refrigerant flow flowing through the first microchannel 610; the first microchannel 610 is a U-shaped flow path at this time.

Alternatively, one end of the second microchannel 611 penetrates the sidewall of the outer second header 622 and is inserted into the outer second header 622. The other end of the second microchannel 611 penetrates the sidewalls in the two second headers 622 and is inserted into the inner second header 622. The outer second collecting pipe 622 is configured to provide a second refrigerant flow to the second microchannel 611, and the inner second collecting pipe 622 is configured to collect the second refrigerant flow flowing through the second microchannel 611; alternatively, the inner second collecting pipe 622 is used for providing the second refrigerant flow to the second microchannel 611, and the outer second collecting pipe 622 is used for collecting the second refrigerant flow flowing through the second microchannel 611; the second microchannel 611 is a U-shaped flow path at this time.

2. Sleeve type heat exchanger

As shown in fig. 7, the heat exchanger 6 includes a heat exchange body 61, and the heat exchange body 61 includes a first tubular body 614 and a second tubular body 615 which are nested with each other. A plurality of first microchannels 610 are arranged in the first tube 614, a plurality of second microchannels 611 are arranged in the second tube 615, and the plurality of first microchannels 610 and the plurality of second microchannels 611 are the same as the microchannels 612 shown in fig. 2, so that the length of the heat exchange main body 61 is shortened, and the volume of the heat exchanger 6 is further reduced.

The plurality of first microchannels 610 of the first tubular body 614 serve as first heat exchange channels 610 of the heat exchanger 6 and the plurality of second microchannels 611 of the second tubular body 615 serve as second heat exchange channels 611 of the heat exchanger 6. Wherein, the extending direction of first microchannel 610 and the extending direction of second microchannel 611 are parallel to each other, for example, the extending direction of first microchannel 610 is the same as the extending direction of second microchannel 611.

In this embodiment, the first tube 614 is sleeved outside the second tube 615, and the outer surface of the first tube 614 is provided with at least one flat surface 616 to form a heat exchange contact surface of the first tube 614, as shown in fig. 8. Heat dissipation elements or electronic components may be disposed on the planar surface 616 for ease of mounting. In other embodiments, the second tube 615 can be disposed outside the first tube 614.

In the air conditioning system shown in fig. 1, the first refrigerant flow may be a liquid-phase refrigerant flow, and the second refrigerant flow may be a gas-liquid two-phase refrigerant flow. The second refrigerant stream absorbs heat from the first refrigerant stream of the first microchannels 610 during flow along the second microchannels 611 and is further vaporized to further subcool the first refrigerant stream. In other embodiments, the first refrigerant flow and the second refrigerant flow may adopt other arrangements described above.

In contrast to the heat exchanger 6 shown in fig. 2: the heat exchange body 61 has a large cross-sectional area, and pressure loss of the refrigerant flow can be reduced. In addition, the first pipe 614 is sleeved outside the second pipe 615, so that the heat exchange area between the first microchannels 610 and the second microchannels 611 can be increased, and the heat exchange efficiency between the first heat exchange channels 610 and the second heat exchange channels 611 can be increased.

Referring to fig. 4, the heat exchanger 6 further comprises a header assembly 62, the header assembly 62 comprises a first header 621 and a second header 622, the first header 621 is provided with a first header passage, and the second header 622 is provided with a second header passage. The cross-sectional shape of the heat exchanger 6 is I-shaped, for example, the cross-sectional shape of the heat exchanger 6 along the flowing direction of the refrigerant flow in the heat exchange body 61 is I-shaped. In other embodiments, the cross-sectional shape of the heat exchanger 6 along the flow direction of the refrigerant flow in the heat exchange body 61 may be L-shaped, U-shaped, G-shaped, or circular.

The first collecting channel is connected to the first microchannels 610 to provide a first refrigerant flow to the plurality of first microchannels 610 through the first collecting channel and/or to collect the first refrigerant flow flowing through the plurality of first microchannels 610. The number of the first collecting pipes 621 is two, and the two first collecting pipes 621 are respectively connected to two ends of the first pipe body 614, so that one of the two first collecting pipes 621 is used for providing a first refrigerant flow to the plurality of first microchannels 610; and the other of the two first headers 621 is used to collect the first refrigerant flow passing through the plurality of first microchannels 610.

The second collecting channel is connected to the second microchannels 611 to provide a second refrigerant flow to the plurality of second microchannels 611 through the second collecting channel and/or to collect the second refrigerant flow flowing through the plurality of second microchannels 611. The number of the second collecting pipes 622 is two, and the two second collecting pipes 622 are respectively connected to two ends of the second pipe 615, so as to provide a second refrigerant flow to the plurality of second microchannels 611 by using one of the two second collecting pipes 622; and the second refrigerant flow passing through the second microchannels 611 is collected by the other of the two second headers 622.

Alternatively, the heat exchange body 61 may include at least two sets of the first and

second tubes

614 and 615, the at least two sets of the first and

second tubes

614 and 615 being spaced apart from each other in a direction perpendicular to the extending direction. For example, the at least two sets of first and

second tubes

614, 615 may include a first set of first and

second tubes

614, 615 nested within each other, a second set of first and

second tubes

614, 615 nested within each other, the first and second sets of first and

second tubes

614, 615 nested within each other being spaced apart from the second set of first and

second tubes

614, 615 along a direction perpendicular to the direction of extension.

The same end of the first tube 614 of the at least two groups of first tubes 614 and the same end of the second tube 615 of the at least two groups of first tubes 615 are connected to the same first header 621, and the same end of the second tube 615 of the at least two groups of first tubes 614 and the same end of the second tube 615 of the at least two groups of second tubes 615 are connected to the same second header 622, so that the cost can be reduced.

The manifold assembly 62 may also be provided in the various manifold arrangements described above, such as the first manifold 621 and the second manifold 622 spaced apart from each other, the manifold 623 and the cutoff 624, or the first manifold 621 and the second manifold 622 nested within each other, as described above. At this time, the first tube 614 with the first micro-channel 610 thereon and the second tube 615 with the second micro-channel 611 thereon can be matched with the above-mentioned header in the manner described above, and are not described herein again.

3. The heat exchanger has a first plate body and a second plate body which are arranged in a stacked manner

As shown in fig. 9, the heat exchanger 6 includes a heat exchange body 61, and the heat exchange body 61 includes a first plate body 631 and a second plate body 632, and the first plate body 631 and the second plate body 632 are stacked on each other.

A plurality of first microchannels 610 are disposed in the first plate 631, a plurality of second microchannels 611 are disposed in the second plate 632, and the plurality of first microchannels 610 and the plurality of second microchannels 611 are the same as the microchannels 612 shown in fig. 2, and are not described herein again. Therefore, the length of the heat exchange body 61 is shortened, and the volume of the heat exchanger 6 is reduced.

The first plurality of microchannels 610 of the first plate body 631 serves as a first heat exchange channel 610 of the heat exchanger 6 and the second plurality of microchannels 611 of the second plate body 632 serves as a second heat exchange channel 611 of the heat exchanger 6. Wherein, the extending direction of first microchannel 610 and the extending direction of second microchannel 611 are parallel to each other, for example, the extending direction of first microchannel 610 is the same as the extending direction of second microchannel 611. Since the first plate body 631 and the second plate body 632 are stacked on each other, the contact area between the first plate body 631 and the second plate body 632 is increased to increase the heat exchange area between the first heat exchange channel 610 and the second heat exchange channel 611, thereby improving the heat exchange efficiency.

In the air conditioning system shown in fig. 1, the first refrigerant flow may be a liquid-phase refrigerant flow, and the second refrigerant flow may be a gas-liquid two-phase refrigerant flow. The second refrigerant stream absorbs heat from the first refrigerant stream of the plurality of first microchannels 610 during flow along the plurality of second microchannels 611 and is further vaporized such that the first refrigerant stream is further subcooled. In other embodiments, the first refrigerant flow and the second refrigerant flow may adopt other arrangements described above.

In an embodiment, the number of the first plate 631 may be two, and the second plate 632 is sandwiched between the two first plates 631, for example, the first plate 631, the second plate 632, and the first plate 631 are stacked in sequence. The second plate body 632 is clamped between the two first plate bodies 631, so that the second refrigerant flow of the second plate body 632 absorbs heat of the first refrigerant flows of the two first plate bodies 631 at the same time, and the first refrigerant flows of the two first plate bodies 631 are cooled. In addition, a heat dissipation element or an electronic element may be disposed in heat conductive connection with the first plate 631, for example, the heat dissipation element or the electronic element may be disposed on a surface of the first plate 631 away from the second plate 632 for easy installation. In an embodiment, the two first plates 631 may be two independent plates. In other embodiments, the two first plate bodies 631 may also be integrally connected in a U shape, in which case the first microchannels 610 in the two first plate bodies 631 are connected in a U shape, so that the inlet and the outlet of the first microchannels 610 are located on the same side of the heat exchange body 61.

In other embodiments, the number of the second plate 632 may be two, and the first plate 631 is sandwiched between the two second plates 632. At this time, a heat dissipation element or an electronic element may be disposed in thermal conductive connection with the second board body 632.

As shown in fig. 10, the heat exchanger 6 further comprises a header pipe assembly 62, the header pipe assembly 62 comprises a first header 621 and a second header 622, the first header 621 is provided with a first header passage, and the second header 622 is provided with a second header passage. The cross-sectional shape of the heat exchanger 6 along the flow direction of the refrigerant flow in the heat exchange body 61 is I-shaped. In other embodiments, the cross-sectional shape of the heat exchanger 6 along the flow direction of the refrigerant flow in the heat exchange body 61 may be L-shaped, U-shaped, G-shaped, or circular.

The first collecting channel is connected to the first microchannels 610 to provide a first refrigerant flow to the plurality of first microchannels 610 through the first collecting channel and/or to collect the first refrigerant flow flowing through the plurality of first microchannels 610. The number of the first collecting pipes 621 is two, and the two first collecting pipes 621 are respectively connected to two ends of the first plate body 631, so as to provide a first refrigerant flow to the plurality of first microchannels 610 by using one of the two first collecting pipes 621; and the other of the two first headers 621 is used to collect the first refrigerant flow passing through the plurality of first microchannels 610.

The second collecting channel is connected to the second microchannels 611 to provide a second refrigerant flow to the plurality of second microchannels 611 through the second collecting channel and/or to collect the second refrigerant flow flowing through the plurality of second microchannels 611. The number of the second collecting pipes 622 is two, and the two second collecting pipes 622 are respectively connected to two ends of the second plate body 632, so as to provide a second refrigerant flow to the plurality of second microchannels 611 by using one of the two second collecting pipes 622; and the second refrigerant flow passing through the second microchannels 611 is collected by the other of the two second headers 622.

second plate bodies

631 and 632 spaced apart from each other in a direction perpendicular to the extending direction. For example, as shown in fig. 10, the heat exchange body 61 includes three sets of first plate bodies 631 and second plate bodies 632, and the three sets of first plate bodies 631 and second plate bodies 632 are arranged at intervals in a direction perpendicular to the extending direction of the first microchannels 610 or the extending direction of the second microchannels 611.

The same end of the first plate 631 of the at least two groups of first plate 631 and the same end of the second plate 632 are connected to the same first collecting pipe 621, the same end of the second plate 632 of the at least two groups of first plate 631 and the second plate 632 are connected to the same second collecting pipe 622, for example, the same end of all the first plates 631 of the heat exchange main body 61 is connected to the same first collecting pipe 621, and the same end of all the second plates 632 of the heat exchange main body 61 is connected to the same second collecting pipe 622, so that the cost is reduced.

In this embodiment, the first header 621 and the second header 622 are disposed at intervals along the extending direction of the heat exchange body 61. The second plate body 632 penetrates through the first header 621 and is inserted into the second header 622, wherein the first header 621 is disposed between the second header 622 and the heat exchange main body 61, the second plate body 632 penetrates through the first header 621 and is inserted into the second header 622 and welded and fixed, and the first plate body 631 is inserted into the first header 621 and welded and fixed. In other embodiments, the first plate 631 may penetrate the second header 622 and then be connected to the first header 621.

The distance between the first header 621 and the second header 622 is R-2r, R being the maximum cross-sectional dimension of the first header 621 in the direction of the separation of the first header 621 and the second header 622. The cross-sectional shapes of the first header 621 and the second header 622 may be both circular, and R is the diameter of the first header 621 or the diameter of the second header 622. Further, as described above, when the cross-sectional shapes of the first header 621 and the second header 622 are non-circular, R is the diameter of the circle circumscribed by the first header 621 or the second header 622.

The manifold assembly 62 may also be provided in the various manifold arrangements described above, such as the manifold 623 and cutoff 624 arrangement described above, or the first and

second manifolds

621 and 622 nested within one another. At this time, the first plate 631 with the first micro-channels 610 thereon and the second plate 633 with the second micro-channels 611 thereon can be matched with the above-mentioned header in the manner described above, and will not be described again.

4. Auxiliary heat exchanger of air conditioner outdoor unit

As shown in fig. 11, the outdoor unit of an air conditioner includes a base plate 41, a casing 42, and an auxiliary heat exchanger 43, and the auxiliary heat exchanger 43 is the heat exchanger 6 disclosed in the above embodiment.

The housing 42 is disposed on the bottom chassis 41 such that the housing 42 and the bottom chassis 41 form an installation cavity 421, and the auxiliary heat exchanger 43 is disposed in the installation cavity 421. The auxiliary heat exchanger 43 includes a heat exchange body 61 and a header assembly 62, the header assembly 62 is used for providing a refrigerant flow to the heat exchange body 61, and the heat exchange body 61 is used for heating the installation cavity 421.

The heat exchange main body 61 includes a first heat exchange passage 610 and a second heat exchange passage 611, the header assembly 62 includes a first header 621 and a second header 622, the first header 621 is provided with a first header passage, and the second header 622 is provided with a second header passage. The first collecting channel is connected to the first heat exchanging channel 610 to provide the first refrigerant flow to the first heat exchanging channel 610 through the first collecting channel and/or collect the first refrigerant flow flowing through the first heat exchanging channel 610. The second collecting channel is connected to the second heat exchanging channel 611 to provide the second refrigerant flow to the second heat exchanging channel 611 through the second collecting channel and/or to collect the second refrigerant flow flowing through the second heat exchanging channel 611.

The number of the first collecting pipes 621 is two, and the two first collecting pipes 621 are respectively connected to two ends of the first heat exchange passage 610, so that one of the two first collecting pipes 621 is used for providing a first refrigerant flow to the first heat exchange passage 610; and the other of the two first headers 621 is used to collect the first refrigerant flow passing through the first heat exchange channel 610. The number of the second collecting pipes 622 is two, and the two second collecting pipes 622 are respectively connected to two ends of the second heat exchange channel 611, so that one of the two second collecting pipes 622 is used for providing a second refrigerant flow to the second heat exchange channel 611; and the other of the two second headers 622 is used to collect the second refrigerant flow passing through the second heat exchanging channel 611.

The second refrigerant flow is a gas-liquid two-phase refrigerant flow, the first refrigerant flow is a liquid-phase refrigerant flow, and the second refrigerant flow absorbs heat from the first refrigerant flow in the flowing process along the second heat exchange channel 611 and is further gasified, so that the first refrigerant flow is further supercooled. For example, the first refrigerant flow is a medium-pressure medium-temperature refrigerant flow, and the temperature can be 40 °; the second refrigerant flow is a low-pressure and low-temperature refrigerant flow, the temperature of the second refrigerant flow can be 10 degrees, and because the temperature of the first refrigerant flow and the temperature of the second refrigerant flow are both different from the ambient temperature, the heat exchange main body 61 emits heat outwards to realize the heating installation cavity 421.

The outdoor unit is installed outdoors, and in a case where an ambient temperature is low (for example, the ambient temperature is-20 °), condensed water discharged from the outdoor unit is frozen, which causes a chassis 41 and a casing 42 of the outdoor unit to be frozen. Therefore, the auxiliary heat exchanger 43 is disposed in the installation chamber 421 to heat the installation chamber 421 through the heat exchange body 61 to prevent the bottom plate 41 and the case 42 from being frozen. In addition, the auxiliary heat exchanger 43 does not need to be powered, and potential safety hazards of electric leakage are avoided.

In an embodiment, the auxiliary heat exchanger 43 is mounted on the base plate 41, and the auxiliary heat exchanger 43 may be mounted on the base plate 41 in a horizontal plane due to the small volume of the auxiliary heat exchanger 43, or the auxiliary heat exchanger 43 may be mounted on the base plate 41 in a direction perpendicular to the horizontal plane.

As shown in fig. 12, the base plate 41 is provided with a drain hole 411, and the drain hole 411 is used for draining water. The auxiliary heat exchanger 43 is installed near the drain hole 411, for example, the auxiliary heat exchanger 43 is installed on the drain hole 411 to heat the chassis 41 near the drain hole 411 to prevent the condensed water from freezing and blocking the drain hole 411, thereby affecting the drainage function of the drain hole 411.

The outdoor unit of the air conditioner further includes a mounting bracket 412, the mounting bracket 412 is provided with a supporting portion and a fixing portion, the supporting portion and the fixing portion are stepped, the auxiliary heat exchanger 43 is mounted on the supporting portion, and the fixing portion is fixed on the base plate 41, so that the auxiliary heat exchanger 43 is disposed on the drain hole 411, the auxiliary heat exchanger 43 is prevented from blocking the drain of the drain hole 411, and the mounting is easy and the cost is low. In other embodiments, the auxiliary heat exchanger 43 may be disposed on the chassis 41 by other fixing methods, such as welding or fixing methods such as sheet metal.

In an embodiment, the outdoor unit of the air conditioner further includes a main heat exchanger, which may be the outdoor heat exchanger 4 disclosed in the above embodiment. The main heat exchanger is disposed in the installation cavity 421, the main heat exchanger is frosted or frozen when the ambient temperature is low, and the auxiliary heat exchanger 43 is installed near the main heat exchanger, for example, the auxiliary heat exchanger 43 is installed at the bottom of the main heat exchanger or the housing 42 is near the main heat exchanger. Therefore, the main heat exchanger can be prevented from frosting or icing under the condition of low ambient temperature, so that the heat exchange efficiency of the main heat exchanger is improved.

5. Control method for heating of auxiliary heat exchanger

As shown in fig. 13, the air conditioning system 1 includes a compressor 2, a four-way valve 3, an outdoor heat exchanger 4, an indoor heat exchanger 5, an auxiliary heat exchanger 43, a first expansion valve 11, a second expansion valve 12, a third expansion valve 13, a first temperature detection device 14, and a second temperature detection device 15, the compressor 2 provides a refrigerant flow of a circulating flow between the outdoor heat exchanger 4 and the indoor heat exchanger 5 through the four-way valve 3, and the third expansion valve 13 is disposed between the outdoor heat exchanger 4 and the indoor heat exchanger 5. The outdoor heat exchanger 4 may be a main heat exchanger of the air conditioner outdoor unit in fig. 12, and the auxiliary heat exchanger 43 may be installed near the drain hole 411 or the main heat exchanger.

An inlet of the first heat exchange passage 610 of the auxiliary heat exchanger 43 is connected to the compressor 2 through the first expansion valve 11, and an outlet of the first heat exchange passage 610 is connected between the outdoor heat exchanger 4 and the indoor heat exchanger 5. An inlet of the first heat exchange passage 610 is connected to the discharge port 21 of the compressor 2 through the first expansion valve 11 via the first header 621, and an outlet of the first heat exchange passage 610 is connected between the outdoor heat exchanger 4 and the indoor heat exchanger 5 through the first header 621.

An inlet of the second heat exchange passage 611 is connected between the outdoor heat exchanger 4 and the indoor heat exchanger 5 through the second expansion valve 12, and an outlet of the second heat exchange passage 611 is connected to the compressor 2. Wherein, the inlet of the second heat exchange channel 611 is connected between the outdoor heat exchanger 4 and the indoor heat exchanger 5, i.e. the outlet of the first heat exchange channel 610, through the second expansion valve 12 via the second collecting pipe 622; the outlet of the second heat exchange channel 611 is connected to the suction port 22 of the compressor 2. In other embodiments, the compressor 2 may be provided with an injection port (not shown), and the outlet of the second heat exchanging channel 611 may be connected to the injection port of the compressor 2, so that the gasified second refrigerant flow passes through the injection port of the compressor 2 to perform enhanced vapor injection on the compressor 2.

Wherein the inlet of the first heat exchange channel 610 is the first end of the first heat exchange channel 610, and the outlet of the first heat exchange channel 610 is the second end of the first heat exchange channel 610. The inlet of the second heat exchange channel 611 is a first end of the second heat exchange channel 611, and the outlet of the second heat exchange channel 611 is a second end of the second heat exchange channel 611.

The first temperature detecting device 14 may be disposed near the outdoor heat exchanger 4 for detecting the ambient temperature T of the air conditioning system 1. The second temperature detecting means 15 may be disposed at the outlet of the first heat exchanging passage 610 for detecting the outlet temperature T1 of the first heat exchanging passage 610, for example, the second temperature detecting means 15 is disposed on the first header 621 connected to the outlet of the first heat exchanging passage 610 for detecting the outlet temperature T1 of the first heat exchanging passage 610. The first temperature detection device 14 and the second temperature detection device 15 may be thermometers or temperature sensors.

As shown in fig. 14, the control method is applied to the air conditioning system shown in fig. 13, and includes the steps of:

step S141: in response to the heating mode, the ambient temperature T and the outlet temperature T1 of the first heat exchange passage are detected.

The air conditioning system 1 is in a heating mode, and in response to the heating mode, the ambient temperature T and the outlet temperature T1 of the first heat exchange passage 610 are detected. For example, the air conditioning system 1 detects the ambient temperature T of the air conditioning system 1 through the first temperature detecting device 14 and detects the outlet temperature T1 of the first heat exchanging channel 610 through the second temperature detecting device 15 in response to the heating mode.

The air conditioning system 1 is preset with a first preset temperature t1, a second preset temperature t2 and a third preset temperature t3, and the third preset temperature t3 is greater than the first preset temperature t1.

Step S142: the ambient temperature T and the outlet temperature T1 are compared with a first preset temperature T1 and a second preset temperature T2, respectively.

The air conditioning system 1 detects an ambient temperature T and an outlet temperature T1 of the first heat exchange channel 610, and compares the ambient temperature T and the outlet temperature T1 of the first heat exchange channel 610 with a first preset temperature T1 and a second preset temperature T2, respectively. That is, the air conditioning system 1 compares the ambient temperature T with the first preset temperature T1, and compares the outlet temperature T1 of the first heat exchange channel 610 with the second preset temperature T2.

Step S143: in response to the ambient temperature T being less than the first preset temperature T1 and the outlet temperature T1 of the first heat exchange channel 610 being less than the second preset temperature T2, the opening degree of the first expansion valve 11 is increased.

The air conditioning system 1 opens the opening degree of the first expansion valve 11 in response to the ambient temperature T being less than the first preset temperature T1 and the outlet temperature T1 of the first heat exchange passage 610 being less than the second preset temperature T2.

The air conditioning system 1 responds to the ambient temperature T being less than the first preset temperature T1, that is, the ambient temperature T of the air conditioning system 1 is low, for example, the first preset temperature T1 is-5 °, the ambient temperature T of the air conditioning system 1 is less than-5 °, and frosting or icing of the outdoor unit of the air conditioner may occur. The air conditioning system 1 is further responsive to the outlet temperature T1 of the first heat exchanging channel 610 being less than the second preset temperature T2, that is, the temperature of the first refrigerant flowing through the first heat exchanging channel 610 is less than the second preset temperature T2, for example, the second preset temperature T2 is 10 °. At this time, the air conditioning system 1 increases the opening degree of the first expansion valve 11 to increase the flow rate of the first refrigerant flow, increase the outlet temperature T1 of the first heat exchange channel 610, and increase the heat dissipation capacity of the first heat exchange channel 610, so that the auxiliary heat exchanger 43 heats the air conditioning outdoor unit to remove frost or ice from the air conditioning outdoor unit.

Alternatively, the air conditioning system 1 opens the second expansion valve 12, and the second refrigerant flow absorbs heat from the first refrigerant flow of the first heat exchange channel 610 during the flowing process along the second heat exchange channel 611, and is further gasified, so that the first refrigerant flow is further supercooled.

In one embodiment, the air conditioning system 1 is in response to a non-heating mode, for example, the air conditioning system 1 is in a cooling mode, i.e., the ambient temperature T of the air conditioning system 1 is high, so that the outdoor unit of the air conditioner does not frost or ice. The air conditioning system 1 closes the first expansion valve 11 and the first heat exchange passage 610 is closed; the opening degree of the second expansion valve 12 is decreased to decrease the flow rate of the second refrigerant flowing through the second heat exchange channel 611.

In addition, the second refrigerant flow flowing through the second heat exchanging channel 611 may exchange heat with the environment of the air conditioning system 1, for example, the second refrigerant flow absorbs heat from the environment of the air conditioning system 1, so as to further gasify the second refrigerant flow. The gasified second refrigerant flow is used for supplementing air and increasing enthalpy to the compressor 2 through the injection port or the air suction port 22 of the compressor 2, and the heating capacity of the air conditioning system 1 is improved.

As shown in fig. 15, step S142 further includes the steps of:

step S151: the ambient temperature T is compared with a third preset temperature T3.

In response to the ambient temperature T being greater than the first preset temperature T1, the air conditioning system 1 compares the ambient temperature T with a third preset temperature T3, where the third preset temperature T3 is greater than the first preset temperature T1.

Step S152: in response to the ambient temperature T being greater than or equal to the third preset temperature T3, the opening degree of the first expansion valve 11 is closed.

The air conditioning system 1 is in the heating mode, and in response to the ambient temperature T being greater than or equal to the third preset temperature T3, the opening degree of the first expansion valve 11 is decreased, so as to decrease the flow rate of the first refrigerant flowing through the first heat exchange channel 610, thereby decreasing the heat dissipation capacity of the first heat exchange channel 610.

As shown in fig. 16, step S142 further includes the steps of:

step S161: the outlet temperature T1 is compared with a fourth preset temperature T4, the fourth preset temperature T4 being greater than the second preset temperature T2.

The air conditioning system 1 is preset with a fourth preset temperature t4, and the fourth preset temperature t4 is greater than the second preset temperature t2; the air conditioning system 1 compares the outlet temperature T1 with a fourth preset temperature T4.

Step S162: in response to the outlet temperature T1 being greater than or equal to the fourth preset temperature T4, the opening degree of the first expansion valve 11 is closed down, and the opening degree of the second expansion valve 12 is opened up.

In response to the outlet temperature T1 being greater than or equal to the fourth preset temperature T4, that is, the temperature of the first refrigerant flow flowing through the first heat exchange channel 610 is too high, in order to achieve supercooling of the first refrigerant flow, the air conditioning system 1 decreases the opening degree of the first expansion valve 11 and increases the opening degree of the second expansion valve 12. Therefore, the air conditioning system 1 reduces the flow rate of the first refrigerant flowing through the first heat exchange channel 610 to reduce the heat dissipation capacity of the first heat exchange channel 610; the flow rate of the second refrigerant flowing through the second heat exchanging channel 611 is increased, so that the second refrigerant absorbs heat from the first refrigerant, and the first refrigerant is further supercooled.

6. Compressor bypass pressure relief

As shown in fig. 17, the air conditioning system 1 includes a compressor 2, a four-way valve 3, an outdoor heat exchanger 4, an indoor heat exchanger 5, an auxiliary heat exchanger 43, a second expansion valve 12, a third expansion valve 13, a solenoid valve 16, a temperature detection device 17, and an air pressure detection device 18, the compressor 2 provides a refrigerant flow of a circulating flow between the outdoor heat exchanger 4 and the indoor heat exchanger 5 through the four-way valve 3, and the third expansion valve 13 is disposed between the outdoor heat exchanger 4 and the indoor heat exchanger 5.

An inlet of the first heat exchange path 610 of the auxiliary heat exchanger 43 is connected to the compressor 2 through the solenoid valve 16, and an outlet of the first heat exchange path 610 is connected between the outdoor heat exchanger 4 and the indoor heat exchanger 5. Wherein, the inlet of the first heat exchanging channel 610 is connected to the exhaust port 21 of the compressor 2 through the first collecting pipe 621 via the solenoid valve 16, and the outlet of the first heat exchanging channel 610 is connected to the space between the outdoor heat exchanger 4 and the indoor heat exchanger 5 through the first collecting pipe 621.

An inlet of the second heat exchange passage 611 is connected between the outdoor heat exchanger 4 and the indoor heat exchanger 5 through the second expansion valve 12, and an outlet of the second heat exchange passage 611 is connected to the compressor 2. Wherein, the inlet of the second heat exchange channel 611 is connected between the outdoor heat exchanger 4 and the indoor heat exchanger 5, i.e. the outlet of the first heat exchange channel 610, through the second expansion valve 12 via the second collecting pipe 622; the outlet of the second heat exchange channel 611 is connected to the suction port 22 of the compressor 2. In other embodiments, the compressor 2 may be provided with an injection port (not shown), and an outlet of the second heat exchanging channel 611 may be connected to the injection port of the compressor 2, so that the gasified second refrigerant flow performs enhanced vapor injection on the compressor 2 through the injection port of the compressor 2, thereby improving the cooling capacity of the air conditioning system 1.

A temperature detecting device 17 may be disposed at the outlet of the second heat exchanging channel 611 for detecting the outlet temperature T2 of the second heat exchanging channel 611, for example, the temperature detecting device 17 is disposed on the second header 622 connected to the outlet of the second heat exchanging channel 611 for detecting the outlet temperature T2 of the second heat exchanging channel 611. The temperature detection device 17 may be a thermometer or a temperature sensor.

The air pressure detecting means 18 may be provided at the discharge port 21 of the compressor 2 for detecting the pressure value P of the discharge pressure of the compressor 2, and the air pressure detecting means 18 may be a pressure sensor, a pressure gauge, or the like.

As shown in fig. 18, the control method is applied to the air conditioning system 1 shown in fig. 17, and includes the steps of:

step S181: the pressure value P of the compressor 2 and the outlet temperature T2 of the second heat exchange channel 611 are detected.

The air conditioning system 1 detects a pressure value P of the compressor 2, for example, the air conditioning system 1 detects a pressure value P of a discharge pressure of the compressor 2 by the air pressure detecting device 18. The air conditioning system 1 detects the outlet temperature T2 of the second heat exchange channel 611, for example, the air conditioning system 1 detects the outlet temperature T2 of the second heat exchange channel 611 through the temperature detecting device 17.

Step S182: the pressure value P is compared with a first preset pressure value P1.

The air conditioning system 1 is preset with a first preset pressure value P1, and the detected pressure value P is compared with the first preset pressure value P1. In response to the pressure value P being greater than or equal to the first preset pressure value P1, the air conditioning system 1 proceeds to step S183.

Step S183: in response to the pressure value P being greater than or equal to the first preset pressure value P1, the solenoid valve 16 is opened.

In response to the pressure value P being greater than or equal to the first preset pressure value P1, the air conditioning system 1 opens the electromagnetic valve 16, so that the exhaust port 21 of the compressor 2 realizes bypass pressure relief through the first heat exchange channel 610, so as to reduce the exhaust pressure of the compressor 2.

Step S184: the difference T2-Te between the outlet temperature T2 of the second heat exchange channel 611 and the low pressure saturation temperature Te is calculated and the difference T2-Te is compared with the first preset temperature T1.

Since the first heat exchange channel 610 is used to discharge the pressure of the discharge port 21 of the compressor 2, in order to prevent the discharge pressure of the first heat exchange channel 610 from being too high, the second heat exchange channel 611 is used to reduce the temperature and pressure of the first heat exchange channel 610.

The air conditioning system 1 is preset with a first preset temperature T1 and a low-pressure saturation temperature Te, and a difference between the outlet temperature T2 of the second heat exchange channel 611 and the low-pressure saturation temperature Te is calculated, and the difference is T2-Te. The air conditioning system 1 further compares the difference T2-Te with the first preset temperature T1.

In response to the difference T2-Te being less than the first preset temperature T1, the air conditioning system 1 maintains the opening degree of the second expansion valve 12. In response to the difference T2-Te being greater than or equal to the first preset temperature T1, the process proceeds to step S185.

Step S185: the opening degree of the second expansion valve 12 is increased in response to the difference T2-Te being greater than or equal to the first preset temperature T1.

In response to the difference T2-Te being greater than or equal to the first preset temperature T1, the air conditioning system 1 increases the opening degree of the second expansion valve 12, and increases the flow rate of the second refrigerant flowing through the second heat exchange channel 611, so that the first refrigerant flowing through the first heat exchange channel 610 exchanges heat with the second refrigerant flowing through the second heat exchange channel 611, and the temperature and the pressure of the first heat exchange channel 610 are reduced.

The difference T2-Te represents the superheat of the second refrigerant flow, so as to ensure that the second refrigerant flow at the outlet of the second heat exchange channel 611 is in a gas phase. The air conditioning system 1 increases the opening degree of the second expansion valve 12 to ensure that the second refrigerant flow at the outlet of the second heat exchange channel 611 is in a gas phase, thereby avoiding the liquid return of the compressor 2 and improving the reliability of the air conditioning system 1.

As shown in fig. 19, step S182 further includes the steps of:

step S191: and comparing the pressure value P with a second preset pressure value P2, wherein the second preset pressure value P2 is smaller than the first preset pressure value P1.

A second preset pressure value P2 is preset in the air conditioning system 1, and the second preset pressure value P2 is smaller than the first preset pressure value P1; the air conditioning system 1 further compares the pressure value P with a second preset pressure value P2.

In response to the pressure value P being greater than or equal to the second preset pressure value P2 and the pressure value P being less than the first preset pressure value P1, the air conditioning system 1 maintains the state of the electromagnetic valve 16. In response to the pressure value P being smaller than the second preset pressure value P2, the air conditioning system 1 proceeds to step S192.

Step S192: in response to the pressure value P being less than the second preset pressure value P2, the solenoid valve 16 is closed, and the opening degree of the second expansion valve 12 is closed.

In response to the pressure value P being smaller than the second preset pressure value P2, the air conditioning system 1 closes the electromagnetic valve 16, and closes the opening degree of the second expansion valve 12. That is, the pressure value P of the discharge pressure of the compressor 2 is smaller than the second preset pressure value P2, and the bypass pressure relief of the first heat exchange channel 610 is not required, so that the electromagnetic valve 16 is closed by the air conditioning system 1, and the temperature and the pressure of the first heat exchange channel 610 are not required to be reduced through the second heat exchange channel 611, so that the opening degree of the second expansion valve 12 is reduced by the air conditioning system 1.

As shown in fig. 20, step S184 further includes the steps of:

s201: comparing the difference T2-Te with a second preset temperature T2, wherein the second preset temperature T2 is less than the first preset temperature T1.

The air conditioning system 1 is preset with a second preset temperature t2, wherein the second preset temperature t2 is smaller than the first preset temperature t1. The air conditioning system 1 compares the difference T2-Te with the second preset temperature T2 in response to the difference T2-Te being less than the first preset temperature T1.

The air conditioning system 1 maintains the opening degree of the second expansion valve 12 in response to the difference T2-Te being less than the first preset temperature T1 and greater than or equal to the second preset temperature T2. In response to the difference T2-Te being less than the second predetermined temperature T2, the air conditioning system 1 proceeds to step S202.

Step S202: in response to the difference T2-Te being less than the second preset temperature T2, the opening degree of the second expansion valve 12 is closed.

In response to the difference T2-Te being less than the second preset temperature T2, the air conditioning system 1 decreases the opening degree of the second expansion valve 12, and decreases the flow rate of the second refrigerant flow of the second heat exchange channel 611. The second refrigerant flow at the outlet of the second heat exchange channel 611 is in a gas phase, so that liquid return of the compressor 2 is avoided, and the reliability of the air conditioning system 1 is improved.

7. Method for controlling temperature of electric control box

As shown in fig. 21, the air conditioning system 1 includes a compressor 2, a four-way valve 3, an outdoor heat exchanger 4, an indoor heat exchanger 5, an auxiliary heat exchanger 43, a second expansion valve 12, a third expansion valve 13, a control valve 19, a temperature detection device 17, an electronic control box 7, and a cavity temperature detection device 24, the compressor 2 provides a refrigerant flow circulating between the outdoor heat exchanger 4 and the indoor heat exchanger 5 through the four-way valve 3, the third expansion valve 13 is disposed between the outdoor heat exchanger 4 and the indoor heat exchanger 5, and the electronic control box 7 and the outdoor heat exchanger 4 are disposed outdoors.

The auxiliary heat exchanger 43 is disposed in the electronic control box 7, and the auxiliary heat exchanger 43 includes a first heat exchange passage 610 and a second heat exchange passage 611. An inlet of the first heat exchange passage 610 of the auxiliary heat exchanger 43 is connected to the compressor 2 through the control valve 19, and an outlet of the first heat exchange passage 610 is connected between the outdoor heat exchanger 4 and the indoor heat exchanger 5. Wherein, the inlet of the first heat exchange channel 610 is connected to the exhaust port 21 of the compressor 2 through the first collecting pipe 621 via the control valve 19, and the outlet of the first heat exchange channel 610 is connected between the outdoor heat exchanger 4 and the indoor heat exchanger 5 through the first collecting pipe 621.

A temperature detecting device 17 may be disposed at the outlet of the second heat exchanging channel 611 for detecting the outlet temperature T2 of the second heat exchanging channel 611, for example, the temperature detecting device 17 is disposed on the second header 622 connected to the outlet of the second heat exchanging channel 611 for detecting the outlet temperature T2 of the second heat exchanging channel 611. The cavity temperature detection device 24 is arranged in the electric control box 7 and used for detecting the cavity temperature Tb of the electric control box 7. The cavity temperature detecting device 24 and the temperature detecting device 17 may be thermometers or temperature sensors.

As shown in fig. 22, the control method is applied to the air conditioning system 1 shown in fig. 21, and includes the steps of:

step S211: and detecting the cavity temperature Tb of the electric control box 7.

The air conditioning system 1 detects the cavity temperature Tb of the electric control box 7 through the cavity temperature detection device 24.

Step S212: the cavity temperature Tb is compared with a first preset temperature t1.

The air conditioning system 1 is preset with a first preset temperature t1, and the air conditioning system 1 compares the cavity temperature Tb with the first preset temperature t1. In response to the cavity temperature Tb being less than the first preset temperature t1, the air conditioning system 1 proceeds to step S213.

Step S213: in response to the cavity temperature Tb being lower than the first preset temperature t1, the control valve 19 is opened, so that the first refrigerant flow of the first heat exchange channel 610 heats the electronic control box 7.

The air conditioning system 1 responds to the cavity temperature Tb being less than the first preset temperature t1, and then opens the control valve 19. Because the cavity temperature Tb is less than the first preset temperature t1, that is, the cavity temperature Tb of the electronic control box 7 is low, the electronic components of the electronic control box 7 cannot work normally; therefore, the air conditioning system 1 opens the control valve 19, so that the first refrigerant flow of the first heat exchange channel 610 exchanges heat with the cavity of the electronic control box 7, and the electronic control box 7 is further heated, thereby ensuring that the electronic components of the electronic control box 7 work normally.

The control valve 19 may be a first expansion valve, and the air conditioning system 1 opens the first expansion valve and adjusts the opening degree of the first expansion valve based on the cavity temperature Tb. For example, the air conditioning system 1 is provided with a first temperature range, a second temperature range, a third temperature range, a first opening degree, a second opening degree, and a third opening degree, the first opening degree corresponding to the first temperature range, the second opening degree corresponding to the second temperature range, and the third opening degree corresponding to the third temperature range; the cavity temperature Tb is within a first temperature range, and the air conditioning system 1 adjusts the opening degree of the first expansion valve 11 to a first opening degree; the cavity temperature Tb is within the second temperature range, and the air conditioning system 1 adjusts the opening degree of the first expansion valve 11 to a second opening degree; the cavity temperature Tb is within the third temperature range, and the air conditioning system 1 adjusts the opening degree of the first expansion valve 11 to the third opening degree.

Optionally, the control valve 19 may be an electromagnetic valve, and the air conditioning system 1 opens the electromagnetic valve in response to the cavity temperature Tb being less than the first preset temperature t1, so that the first refrigerant flow of the first heat exchange channel 610 exchanges heat with the cavity of the electronic control box 7, and the electronic control box 7 is heated, thereby ensuring that the electronic components of the electronic control box 7 normally operate.

In addition, the air conditioning system 1 is preset with a second preset temperature t2, and the second preset temperature t2 is greater than the first preset temperature t1. The air conditioning system 1 also compares the cavity temperature Tb with a second preset temperature t2; in response to the cavity temperature Tb being greater than or equal to the first preset temperature t1 and less than the second preset temperature t2, the air conditioning system 1 maintains the states of the control valve 19 and the second expansion valve 12, for example, the control valve 19 is kept in an open state, and the second expansion valve 12 is kept in an open state, so that the electronic components of the electronic control box 7 operate normally.

In response to the cavity temperature Tb being greater than or equal to the second preset temperature t2, that is, the cavity temperature Tb of the electronic control box 7 is too high, the performance of the electronic components of the electronic control box 7 may be affected by the air conditioning system 1. When the control valve 19 is a first expansion valve, the second refrigerant flow of the second heat exchange channel 611 exchanges heat with the first refrigerant flow of the first heat exchange channel 610, so as to reduce the cavity temperature Tb of the electronic control box 7, and ensure the performance of the electronic components of the electronic control box 7. When the control valve 19 is an electromagnetic valve, the air conditioning system 1 closes the electromagnetic valve, so that the second refrigerant flow of the second heat exchange channel 611 exchanges heat with the cavity of the electronic control box 7, so as to dissipate heat of the electronic control box 7, and ensure the performance of the electronic components of the electronic control box 7. In other embodiments, the air conditioning system 1 may also periodically close and open the solenoid valve.

Through the above manner, the air conditioning system 1 controls the cavity temperature Tb of the electric control box 7 to prolong the service life of the electronic components of the electric control box 7.

As shown in fig. 23, the control method further includes the steps of:

step S221: the outlet temperature T2 of the second heat exchange channel 611 is detected, and the difference between the outlet temperature T2 and the saturation temperature Te of the second refrigerant flow is calculated.

The air conditioning system 1 is preset with a saturation temperature Te of the second refrigerant flow, a third preset temperature t3 and a fourth preset temperature t4, and the fourth preset temperature t4 is smaller than the third preset temperature t3. The air conditioning system 1 detects the outlet temperature T2 of the second heat exchange channel 611 through the temperature detection device 17, and calculates a difference T2-Te between the outlet temperature T2 and the saturation temperature Te of the second refrigerant flow.

Step S222: the difference T2-Te is compared with a third preset temperature T3.

In response to the cavity temperature Tb being greater than or equal to the second preset temperature T2, the air conditioning system 1 compares the difference T2-Te with a third preset temperature T3. In response to the difference T2-Te being greater than or equal to the third preset temperature T3, the air conditioning system 1 proceeds to step S223. In response to the difference T2-Te being less than the third preset temperature T3, the air conditioning system 1 proceeds to step S224.

Step S223: in response to the difference T2-Te being greater than or equal to the third preset temperature T3, the opening degree of the second expansion valve 12 is increased.

In response to the difference T2-Te being greater than or equal to the third preset temperature T3, the air conditioning system 1 increases the opening degree of the second expansion valve 12, and increases the flow rate of the second refrigerant flowing through the second heat exchange channel 611, so that the first refrigerant flowing through the first heat exchange channel 610 exchanges heat with the second refrigerant flowing through the second heat exchange channel 611, so as to reduce the temperature and pressure of the first heat exchange channel 610, and the auxiliary heat exchanger 43 reduces the cavity temperature Tb of the electronic control box 7.

Step S224: the difference T2-Te is compared with a fourth preset temperature T4.

The air conditioning system 1 compares the difference T2-Te with a fourth preset temperature T4. The air conditioning system 1 maintains the opening degree of the second expansion valve 12 in response to the difference T2-Te being greater than or equal to the fourth preset temperature T4. In response to the difference T2-Te being less than the fourth preset temperature T4, the air conditioning system 1 proceeds to step S225.

Step S225: in response to the difference T2-Te being less than the fourth preset temperature T4, the opening degree of the second expansion valve 12 is closed.

In response to the difference T2-Te being less than the fourth preset temperature T4, the air conditioning system 1 decreases the opening degree of the second expansion valve 12 to decrease the flow rate of the second refrigerant flowing through the second heat exchange channel 611. The air conditioning system 1 adjusts the opening degree of the second expansion valve 12 based on the difference value T2-Te to ensure that the second refrigerant flow at the outlet of the second heat exchange channel 611 is in a gas phase, so that the liquid return of the compressor 2 is avoided, and the reliability of the air conditioning system 1 is improved.

8. Control method for heat storage device

As shown in fig. 24, the air conditioning system 1 mainly includes a compressor 2, a four-way valve 3, an outdoor heat exchanger 4, an indoor heat exchanger 5, an auxiliary heat exchanger 43, a heat storage device 45, a first expansion valve 11, a second expansion valve 12, and a third expansion valve 13, the compressor 2 supplies a refrigerant flow that circulates between the outdoor heat exchanger 4 and the indoor heat exchanger 5 through the four-way valve 3, and the third expansion valve 13 is provided between the outdoor heat exchanger 4 and the indoor heat exchanger 5.

As shown in fig. 25, the thermal storage device 45 is a sealed container, and the case 451 of the thermal storage device 45 is made of a heat insulating material, which may include an inorganic heat insulating material, an organic heat insulating material, and a metal heat insulating material. The thermal storage device 45 is provided with a thermal storage material 452, the thermal storage material 452 is provided in the housing 451, the thermal storage material 452 may include paraffin, sodium acetate trihydrate, or the like, and the thermal storage device 45 stores heat by the thermal storage material 452. The auxiliary heat exchanger 43 is provided in the heat storage device 45, and for example, the auxiliary heat exchanger 43 is provided in the heat storage material 452.

In other embodiments, the auxiliary heat exchanger 43 may be disposed on a heat conduction surface 453 of the thermal storage device 45, the material of the heat conduction surface 453 is a heat conduction material, and the thermal storage material 452 of the thermal storage device 45 exchanges heat with the auxiliary heat exchanger 43 through the heat conduction surface 453, as shown in fig. 26.

The auxiliary heat exchanger 43 includes a first heat exchange passage 610 and a second heat exchange passage 611, an inlet of the first heat exchange passage 610 is connected between the third expansion valve 13 and the outdoor heat exchanger 4 through the first expansion valve 11, and an outlet of the first heat exchange passage 610 is connected between the third expansion valve 13 and the indoor heat exchanger 5. An inlet of the second heat exchange passage 611 is connected between the third expansion valve 13 and the indoor heat exchanger 5 through the second expansion valve 12, and an outlet of the second heat exchange passage 611 is connected to the compressor 2. In other embodiments, the compressor 2 may be provided with an injection port (not shown), and an outlet of the second heat exchanging channel 611 may be connected to the injection port of the compressor 2, so that the gasified second refrigerant flow performs enhanced vapor injection on the compressor 2 through the injection port of the compressor 2, thereby improving the cooling capacity of the air conditioning system 1.

As shown in fig. 27, the control method is applied to the air conditioning system shown in fig. 24, and includes the steps of:

step S261: the first expansion valve 11 and the second expansion valve 12 are opened to exchange heat between the first refrigerant flow of the first heat exchange channel 610 and the second refrigerant flow of the second heat exchange channel 611, and the heat storage device 45 stores heat.

The air conditioning system 1 opens the first expansion valve 11 and the second expansion valve 12, the first refrigerant flows through the first heat exchange channel 610 via the first expansion valve 11, and the second refrigerant flows through the second heat exchange channel 611 via the second expansion valve 12. The second refrigerant flow is a gas-liquid two-phase refrigerant flow, the first refrigerant flow is a liquid-phase refrigerant flow, and the first refrigerant flow of the first heat exchange channel 610 and the second refrigerant flow of the second heat exchange channel 611 perform heat exchange, so that the second refrigerant flow absorbs heat from the first refrigerant flow, the second refrigerant flow is further gasified, and the first refrigerant flow is further supercooled. At this time, the thermal storage device 45 is used to store heat.

Step S262: in response to the cooling mode, the outlet temperature T of the outdoor heat exchanger 4 is detected, a first difference between the outlet temperature T of the outdoor heat exchanger 4 and the saturation temperature Te1 of the refrigerant flow is calculated, and the first difference is compared with a preset temperature T.

The air conditioning system 1 further comprises first temperature detecting means 14 for detecting the outlet temperature T of the outdoor heat exchanger 4. The air conditioning system 1 is preset with a preset temperature T, calculates a first difference T-Te1 between the outlet temperature T of the outdoor heat exchanger 4 and the saturation temperature Te1 of the refrigerant flow, and compares the first difference T-Te1 with the preset temperature T. The saturation temperature Te1 of the refrigerant flow is the saturation temperature of the refrigerant flow flowing between the exterior heat exchanger 4 and the interior heat exchanger 5.

Step S263: in response to the first difference T-Te1 being greater than the preset temperature T, the opening degree of the first expansion valve 11 is decreased to allow the second refrigerant flow of the second heat exchange channel 611 to exchange heat with the heat storage device 45.

In response to that the first difference T-Te1 is greater than the preset temperature T, the air conditioning system 1 closes the opening degree of the first expansion valve 11, and reduces the flow rate of the first refrigerant flow of the first heat exchange channel 610, so that the second refrigerant flow of the second heat exchange channel 611 exchanges heat with the heat storage device 45. Because the heat storage device 45 stores heat, the second refrigerant flow of the second heat exchange channel 611 can absorb heat from the heat storage device 45, at this time, the second refrigerant flow of the second heat exchange channel 611 can absorb heat from the heat storage device 45 and the first refrigerant flow of the first heat exchange channel 610 at the same time, so that the second refrigerant flow is completely gasified, and the gasified second refrigerant flow performs enhanced vapor injection on the compressor 2, thereby improving the refrigerating capacity of the air conditioning system 1.

Optionally, the air conditioning system 1 may further compare the first difference T-Te1 with a first preset temperature T1, where the first preset temperature T1 is less than the preset temperature T. In response to the first difference T-Te1 being greater than or equal to the first preset temperature T1 and less than or equal to the preset temperature T, the air conditioning system 1 maintains the opening degree of the first expansion valve 11.

In response to that the first difference T-Te1 is smaller than the first preset temperature T1, the air conditioning system 1 opens the opening of the first expansion valve 11, the flow rate of the first refrigerant flow of the first heat exchange channel 610 increases, and at this time, the second refrigerant flow of the second heat exchange channel 611 can absorb heat from the heat storage device 45 and the first refrigerant flow of the first heat exchange channel 610 simultaneously, so that the second refrigerant flow is completely gasified, and the gasified second refrigerant flow performs vapor injection enthalpy increment on the compressor 2, thereby improving the refrigerating capacity of the air conditioning system 1.

Alternatively, the air conditioning system 1 closes the first expansion valve 11 in response to the heating mode and the second expansion valve 12 is in the closed state; alternatively, the air conditioning system 1 responds to the heating mode, and the second expansion valve 12 is in the open state, the first expansion valve 11 is opened. For example, when the air conditioning system 1 is in the heating mode and the second expansion valve 12 is in the closed state, the air conditioning system 1 closes the first expansion valve 11; alternatively, if the second expansion valve 12 is in the open state, the air conditioning system 1 opens the first expansion valve 11 so that the second refrigerant flow of the second heat exchange channel 611 may absorb heat from the heat storage device 45 and the first refrigerant flow of the first heat exchange channel 610 at the same time.

As shown in fig. 28, the control method includes the steps of:

step S271: the outlet temperature T2 of the second heat exchange channel 611 is detected, and the difference between the outlet temperature T2 and the saturation temperature Te of the second refrigerant flow is calculated.

The air conditioning system 1 is preset with a saturation temperature Te of the second refrigerant flow, a second preset temperature t2 and a third preset temperature t3, wherein the third preset temperature t3 is greater than the second preset temperature t2. The air conditioning system 1 is provided with a temperature detection device 17 for detecting the outlet temperature T2 of the second heat exchange channel 611 and calculating a difference T2-Te between the outlet temperature T2 and the saturation temperature Te of the second refrigerant flow.

Step S272: the difference T2-Te is compared with a second preset temperature T2.

The air conditioning system 1 compares the difference T2-Te with a second preset temperature T2. In response to the difference T2-Te being greater than or equal to the second preset temperature T2, the air conditioning system 1 proceeds to step S274. In response to the difference T2-Te being less than the second preset temperature T2, the air conditioning system 1 proceeds to step S273.

Step S273: in response to the difference T2-Te being less than the second preset temperature T2, the opening degree of the second expansion valve 12 is closed.

In response to the difference T2-Te being smaller than the second preset temperature T2, the air conditioning system 1 closes the opening degree of the second expansion valve 12 to reduce the flow rate of the second refrigerant flowing through the second heat exchange channel 611.

Step S274: the difference T2-Te is compared with a third preset temperature T3.

The air conditioning system 1 compares the difference T2-Te with a third preset temperature T3. In response to the difference T2-Te being greater than or equal to the third preset temperature T3, the air conditioning system 1 proceeds to step S275. The air conditioning system 1 maintains the opening degree of the second expansion valve 12 in response to the difference T2-Te being less than the third preset temperature T3.

Step S275: the opening degree of the second expansion valve 12 is increased in response to the difference T2-Te being greater than or equal to the third preset temperature T3.

In response to that the difference T2-Te is greater than or equal to the third preset temperature T3, the air conditioning system 1 opens the opening degree of the second expansion valve 12, increases the flow rate of the second refrigerant flowing through the second heat exchange channel 611, so that the heat storage device 45 performs heat exchange with the second refrigerant flowing through the second heat exchange channel 611, that is, the second refrigerant flowing through the second heat exchange channel 611 can absorb heat from the heat storage device 45, so that the second refrigerant is completely gasified, and the gasified second refrigerant performs air injection enthalpy increase on the compressor 2, thereby improving the refrigeration capacity of the air conditioning system 1.

9. Method for controlling electric control box by two auxiliary heat exchangers

As shown in fig. 29, the air conditioning system 1 includes a compressor 2, a four-way valve 3, an outdoor heat exchanger 4, an indoor heat exchanger 5, a first auxiliary heat exchanger 431, a second auxiliary heat exchanger 432, a first expansion valve 11, a second expansion valve 12, a third expansion valve 13, a fourth expansion valve 14, a fifth expansion valve 15, a third temperature detection device 171, a fourth temperature detection device 172, an electronic control box 7, a first cavity temperature detection device 24, and a second cavity temperature detection device 25, wherein the compressor 2 provides a refrigerant flow circulating between the outdoor heat exchanger 4 and the indoor heat exchanger 5 through the four-way valve 3, the fifth expansion valve 15 is disposed between the outdoor heat exchanger 4 and the indoor heat exchanger 5, and the electronic control box 7 and the outdoor heat exchanger 4 are disposed outdoors.

The structure of the first auxiliary heat exchanger 431 and the structure of the second auxiliary heat exchanger 432 are the same as the structure of the auxiliary heat exchanger 43, the first auxiliary heat exchanger 431 and the second auxiliary heat exchanger 432 are arranged in the electronic control box 7, the installation position of the second auxiliary heat exchanger 432 is close to the electronic components of the electronic control box 7, and the first auxiliary heat exchanger 431 and the second auxiliary heat exchanger 432 can be arranged in a staggered mode, namely the projection of the first auxiliary heat exchanger 431 on the electronic control box 7 and the projection of the second auxiliary heat exchanger 432 on the electronic control box 7 do not overlap. In other embodiments, the first auxiliary heat exchanger 431 may be disposed to overlap with the second auxiliary heat exchanger 432.

The first auxiliary heat exchanger 431 includes a first heat exchange channel 433 and a second heat exchange channel 434, and the second auxiliary heat exchanger 432 includes a third heat exchange channel 435 and a fourth heat exchange channel 436, the first heat exchange channel 433 and the third heat exchange channel 435 are equivalent to the first heat exchange channel 610 of the auxiliary heat exchanger 43, and the second heat exchange channel 434 and the fourth heat exchange channel 436 are equivalent to the second heat exchange channel 611 of the auxiliary heat exchanger 43.

An inlet of the first heat exchange passage 433 is connected to the discharge port 21 of the compressor 2 through the first expansion valve 11, and an outlet of the first heat exchange passage 433 is connected between the indoor heat exchanger 5 and the fifth expansion valve 15; an inlet of the second heat exchange passage 434 is connected between the indoor heat exchanger 5 and the fifth expansion valve 15 through the second expansion valve 12; an inlet of the third heat exchange path 435 is connected to the discharge port 21 of the compressor 2 through the third expansion valve 13, and an outlet of the third heat exchange path 435 is connected between the indoor heat exchanger 5 and the fifth expansion valve 15; an inlet of the fourth heat exchange path 436 is connected between the indoor heat exchanger 5 and the fifth expansion valve 15 through the fourth expansion valve 14, and an outlet of the fourth heat exchange path 436 and an outlet of the second heat exchange path 434 are connected to the suction port 22 of the compressor 2. In other embodiments, the compressor 2 may be provided with an injection port (not shown), and an outlet of the fourth heat exchanging channel 436 and an outlet of the second heat exchanging channel 434 may be connected to the injection port of the compressor 2, so that the gasified second refrigerant flow performs enhanced vapor injection on the compressor 2 through the injection port of the compressor 2, thereby improving the cooling capacity of the air conditioning system 1.

The third temperature detecting means 171 is disposed at the outlet of the second heat exchanging channel 434, and is configured to detect the outlet temperature T1 of the second heat exchanging channel 434; the fourth temperature detecting device 172 is disposed at the outlet of the fourth heat exchanging channel 436, and is configured to detect the outlet temperature T2 of the fourth heat exchanging channel 436. The first cavity temperature detecting device 24 is disposed near the first auxiliary heat exchanger 431 and is configured to detect a first cavity temperature Tb1, for example, the first cavity temperature detecting device 24 is disposed at an outlet of the first heat exchanging channel 433; the second chamber temperature detecting device 25 is disposed near the third heat exchanging channel 435 for detecting the second chamber temperature Tb2, for example, the second chamber temperature detecting device 25 is disposed at the outlet of the third heat exchanging channel 435. The third temperature detecting device 171, the fourth temperature detecting device 172, the first chamber temperature detecting device 24 and the second chamber temperature detecting device 25 may be thermometers or temperature sensors.

Wherein, the inlet of the first heat exchanging channel 433 is the first end of the first heat exchanging channel 433, and the outlet of the first heat exchanging channel 433 is the second end of the first heat exchanging channel 433. The inlet of second heat exchange channel 434 is a first end of second heat exchange channel 434 and the outlet of second heat exchange channel 434 is a second end of second heat exchange channel 434. The inlet of the third heat exchange channel 435 is a first end of the third heat exchange channel 435, and the outlet of the third heat exchange channel 435 is a second end of the third heat exchange channel 435. The inlet of the fourth heat exchange channel 436 is a first end of the fourth heat exchange channel 436 and the outlet of the fourth heat exchange channel 436 is a second end of the fourth heat exchange channel 436.

As shown in fig. 30, the control method is applied to the air conditioning system 1 shown in fig. 29, and includes the steps of:

step S291: the first cavity temperature Tb1 close to the first auxiliary heat exchanger 431 and the second cavity temperature Tb2 close to the second auxiliary heat exchanger 432 are detected.

The air conditioning system 1 obtains a first cavity temperature Tb1 close to the first auxiliary heat exchanger 431 through detection of the first cavity temperature detection device 24, and obtains a second cavity temperature Tb2 close to the second auxiliary heat exchanger 432 through detection of the second cavity temperature detection device 25. Since the first auxiliary heat exchanger 431 and the second auxiliary heat exchanger 432 are arranged in the electronic control box 7 in a staggered manner, the first cavity temperature Tb1 close to the first auxiliary heat exchanger 431 is not equal to the second cavity temperature Tb2 close to the second auxiliary heat exchanger 432.

Step S292: comparing the first cavity temperature Tb1 with a first preset temperature t1, and comparing the second cavity temperature Tb2 with a second preset temperature t2, wherein the second preset temperature t2 is greater than the first preset temperature t1.

The air conditioning system 1 is preset with a first preset temperature t1 and a second preset temperature t2, and the second preset temperature t2 is greater than the first preset temperature t1. The air conditioning system 1 compares the first cavity temperature Tb1 with the first preset temperature t1, and compares the second cavity temperature Tb2 with the second preset temperature t2. The installation position of the second auxiliary heat exchanger 432 is close to the electronic components of the electronic control box 7, and because the heat productivity of the electronic components is large when the electronic control box 7 works, the first cavity temperature Tb1 is less than the second cavity temperature Tb2.

Step S293: in response to the first cavity temperature Tb1 being lower than the first preset temperature t1, the first expansion valve 11 is opened, and the opening degree of the first expansion valve 11 is adjusted based on the first cavity temperature Tb1, so that the first auxiliary heat exchanger 431 heats the electronic control box 7.

The air conditioning system 1 opens the first expansion valve 11 in response to the first cavity temperature Tb1 being less than the first preset temperature t1, and adjusts the opening degree of the first expansion valve 11 based on the first cavity temperature Tb1, so that the first auxiliary heat exchanger 431 heats the electronic control box 7. For example, the first preset temperature t1 is 0 °, the first cavity temperature Tb1 is less than the first preset temperature t1, and in order to ensure that the electronic components of the electronic control box 7 normally operate, the first expansion valve 11 is opened, so that the refrigerant flow of the first heat exchange channel 433 exchanges heat with the cavity of the electronic control box 7, and the first auxiliary heat exchanger 431 heats the electronic control box 7.

Alternatively, the air conditioning system 1 may open the first expansion valve 11 and the third expansion valve 13 at the same time to achieve that the first auxiliary heat exchanger 431 and the second auxiliary heat exchanger 432 heat the electronic control box 7 at the same time.

Optionally, in response to the first cavity temperature Tb1 being lower than the first preset temperature t1, the air conditioning system 1 opens the first expansion valve 11 and the third expansion valve 13, and closes the second expansion valve 12 and the fourth expansion valve 14, so as to achieve that the first auxiliary heat exchanger 431 and the second auxiliary heat exchanger 432 simultaneously heat the electronic control box 7.

Step S294: in response to the second chamber temperature Tb2 being greater than the second preset temperature t2, the third expansion valve 13 and the fourth expansion valve 14 are opened, so that the second auxiliary heat exchanger 432 dissipates heat from the electronic components of the electronic control box 7.

In response to the second cavity temperature Tb2 being higher than the second preset temperature t2, the air conditioning system 1 opens the third expansion valve 13 and the fourth expansion valve 14, so that the second auxiliary heat exchanger 432 dissipates heat from the electronic components of the electronic control box 7. For example, the second preset temperature t2 is 60 °, the second cavity temperature Tb2 is greater than the second preset temperature t2, the third expansion valve 13 and the fourth expansion valve 14 are opened, and the refrigerant flow of the third heat exchange channel 435 exchanges heat with the refrigerant flow of the fourth heat exchange channel 436, so that the refrigerant flow of the third heat exchange channel 435 is further supercooled. Since the temperature of the refrigerant flow of the third heat exchange channel 435 and the temperature of the refrigerant flow of the fourth heat exchange channel 436 are both lower than the second cavity temperature Tb2, the second auxiliary heat exchanger 432 dissipates heat of the electronic components of the electronic control box 7, so that the electronic components of the electronic control box 7 work normally.

Alternatively, in response to the second cavity temperature Tb2 being greater than the second preset temperature t2, the air conditioning system 1 simultaneously opens the first expansion valve 11, the second expansion valve 12, the third expansion valve 13, and the fourth expansion valve 14 to enable the first auxiliary heat exchanger 431 and the second auxiliary heat exchanger 432 to simultaneously dissipate heat from the electronic control box 7.

As shown in fig. 31, the control method further includes the steps of:

step S301: the outlet temperature T1 of the second heat exchange channel 611 is detected, and a first difference between the outlet temperature T1 of the second heat exchange channel 611 and the saturation temperature Te of the second refrigerant flow is calculated.

The air conditioning system 1 detects the outlet temperature T1 of the second heat exchange channel 434 by the third temperature detecting device 171, and calculates a first difference between the outlet temperature T1 of the second heat exchange channel 434 and the saturation temperature Te of the second refrigerant flow as T1-Te.

Step S302: and respectively comparing the first difference T1-Te with a third preset temperature T3 and a fourth preset temperature T4, wherein the fourth preset temperature T4 is less than the third preset temperature T3.

The air conditioning system 1 compares the first difference T1-Te with a third preset temperature T3 and a fourth preset temperature T4, respectively, and the fourth preset temperature T4 is less than the third preset temperature T3. The air conditioning system 1 is preset with a third preset temperature T3 and a fourth preset temperature T4, and the first difference value T1-Te is compared with the third preset temperature T3; in response to the first difference T1-Te being greater than or equal to the third preset temperature T3, entering step S303; in response to the first difference T1-Te being less than the third preset temperature T3, the first difference T1-Te is compared with a fourth preset temperature T4.

Step S303: the opening degree of the second expansion valve 12 is increased in response to the first difference value T1-Te being greater than or equal to the third preset temperature T3.

In response to the first difference T1-Te being greater than or equal to the third preset temperature T3, the air conditioning system 1 increases the opening degree of the second expansion valve 12, so as to increase the refrigerant fluid flow rate of the second heat exchange channel 434.

Step S304: in response to the first difference T1-Te being less than the fourth preset temperature T4, the opening degree of the second expansion valve 12 is closed.

In response to the first difference T1-Te being less than the fourth preset temperature T4, the air conditioning system 1 decreases the opening degree of the second expansion valve 12, so as to decrease the refrigerant fluid flow rate of the second heat exchange channel 434.

As shown in fig. 32, the control method further includes the steps of:

step S311: and detecting the outlet temperature T2 of the fourth heat exchange channel 436, and calculating a second difference value between the outlet temperature T2 of the fourth heat exchange channel 436 and the saturation temperature Te of the second refrigerant flow.

The air conditioning system 1 detects the outlet temperature T2 of the fourth heat exchange channel 434 through the fourth temperature detecting device 172, and calculates a second difference between the outlet temperature T2 of the fourth heat exchange channel 436 and the saturation temperature Te of the second refrigerant flow as T2 — Te.

Step S312: and respectively comparing the second difference T2-Te with a third preset temperature T3 and a fourth preset temperature T4, wherein the fourth preset temperature T4 is less than the third preset temperature T3.

The air conditioning system 1 compares the second difference T2-Te with a third preset temperature T3 and a fourth preset temperature T4, respectively, where the fourth preset temperature T4 is less than the third preset temperature T3. The air conditioning system 1 presets a third preset temperature T3 and a fourth preset temperature T4, and compares a second difference value T2-Te with the third preset temperature T3; in response to the second difference T2-Te being greater than or equal to the third preset temperature T3, proceeding to step S313; in response to the second difference T2-Te being less than the third preset temperature T3, the second difference T2-Te is compared with a fourth preset temperature T4.

Step S313: the opening degree of the fourth expansion valve 14 is increased in response to the second difference T2-Te being greater than or equal to the third preset temperature T3.

In response to the second difference T2-Te being greater than or equal to the third preset temperature T3, the air conditioning system 1 increases the opening degree of the fourth expansion valve 14, so that the refrigerant fluid flow rate of the fourth heat exchange channel 436 increases.

Step S314: and closing the 14 opening degree of the fourth expansion valve in response to the second difference value T2-Te being less than the fourth preset temperature T4.

In response to the second difference T2-Te being less than the fourth preset temperature T4, the air conditioning system 1 decreases the opening degree of the fourth expansion valve 12, so as to decrease the refrigerant fluid flow rate of the fourth heat exchange channel 436.

The above description is only for the purpose of illustrating embodiments of the present application and is not intended to limit the scope of the present application, and all modifications of equivalent structures and equivalent processes, which are made by the contents of the specification and the drawings of the present application or are directly or indirectly applied to other related technical fields, are also included in the scope of the present application.

Claims

1. A control method is characterized in that the control method is applied to an air conditioning system, the air conditioning system at least comprises a compressor, a four-way valve, an outdoor heat exchanger, an indoor heat exchanger, a first expansion valve, a second expansion valve, a third expansion valve and an auxiliary heat exchanger, the compressor provides a circularly flowing refrigerant flow between the outdoor heat exchanger and the indoor heat exchanger through the four-way valve, the third expansion valve is connected between the indoor heat exchanger and the outdoor heat exchanger, the auxiliary heat exchanger is provided with a heat storage device, a first heat exchange channel and a second heat exchange channel, an inlet of the first heat exchange channel is connected between the third expansion valve and the outdoor heat exchanger through the first expansion valve, an outlet of the first heat exchange channel is connected between the third expansion valve and the indoor heat exchanger, an inlet of the second heat exchange channel is connected between the third expansion valve and the indoor heat exchanger through the second expansion valve, and an outlet of the second heat exchange channel is connected with the compressor, and the control method comprises the following steps:

2. The control method according to claim 1, characterized by further comprising:

comparing the first difference value with a first preset temperature, wherein the first preset temperature is less than the preset temperature;

responding to the first difference value being greater than or equal to the first preset temperature and less than or equal to the preset temperature, and maintaining the opening degree of the first expansion valve;

and in response to the first difference being smaller than the first preset temperature, opening the first expansion valve.

3. The control method according to claim 1, characterized by further comprising:

detecting the outlet temperature of the second heat exchange channel, and calculating the difference between the outlet temperature of the second heat exchange channel and the saturation temperature of a second refrigerant flow;

comparing the difference value with a second preset temperature;

and closing the opening degree of the second expansion valve in response to the difference value being smaller than the second preset temperature.

4. The control method of claim 3, wherein the step of comparing the difference value with a second preset temperature further comprises:

comparing the difference value with a third preset temperature, wherein the third preset temperature is higher than the second preset temperature;

and opening the opening degree of the second expansion valve in response to the difference value being greater than or equal to the third preset temperature.

5. The control method according to claim 1, characterized by further comprising:

responding to a heating mode, and closing the first expansion valve when the second expansion valve is in a closed state;

or, in response to the heating mode and the second expansion valve is in an open state, the first expansion valve is opened.

6. The control method according to claim 1, wherein the auxiliary heat exchanger includes:

the heat exchange body is provided with the first heat exchange channel and the second heat exchange channel; and

the collecting pipe assembly comprises a first collecting pipe and a second collecting pipe, wherein the first collecting pipe is provided with a first collecting channel, the first collecting channel is used for providing a first refrigerant flow for the first heat exchange channel and/or collecting the first refrigerant flow flowing through the first heat exchange channel, the second collecting pipe is provided with a second collecting channel, and the second collecting channel is used for providing a second refrigerant flow for the second heat exchange channel and/or collecting the second refrigerant flow flowing through the second heat exchange channel, so that heat exchange is carried out between the first refrigerant flow flowing through the first heat exchange channel and the second refrigerant flow flowing through the second heat exchange channel.

7. The control method of claim 6, wherein the first heat exchange channel is a plurality of first microchannels disposed within the heat exchange body and the second heat exchange channel is a plurality of second microchannels disposed within the heat exchange body.

8. The control method according to claim 7, wherein the heat exchange main body comprises a first plate body and a second plate body, the first plate body and the second plate body are arranged on top of each other, the plurality of first microchannels are arranged in the first plate body, and the plurality of second microchannels are arranged in the second plate body.

9. The control method of claim 6, wherein the second refrigerant stream absorbs heat from the first refrigerant stream during flow along the second heat exchange channel to subcool the first refrigerant stream, or wherein the first refrigerant stream absorbs heat from the second refrigerant stream during flow along the first heat exchange channel to subcool the second refrigerant stream.

10. An air conditioning system, characterized in that, the air conditioning system at least includes a compressor, a four-way valve, an outdoor heat exchanger, an indoor heat exchanger, a first expansion valve, a second expansion valve, a third expansion valve and an auxiliary heat exchanger, the compressor provides a circularly flowing refrigerant flow between the outdoor heat exchanger and the indoor heat exchanger through the four-way valve, the third expansion valve is connected between the indoor heat exchanger and the outdoor heat exchanger, the auxiliary heat exchanger is provided with a heat storage device, a first heat exchange channel and a second heat exchange channel, an inlet of the first heat exchange channel is connected between the third expansion valve and the outdoor heat exchanger through the first expansion valve, an outlet of the first heat exchange channel is connected between the third expansion valve and the indoor heat exchanger, an inlet of the second heat exchange channel is connected between the third expansion valve and the indoor heat exchanger through the second expansion valve, and an outlet of the second heat exchange channel is connected with the compressor, wherein, the air conditioning system is used for realizing the control method as claimed in any one of claims 1 to 9.