阅读说明：本技术 空调系统 (Air conditioning system ) 是由 都学敏 张恒 孟建军 李廷宇 赵玉垒 于 2021-06-29 设计创作，主要内容包括：本发明公开了一种空调系统包括：室内机模块,包括室内机和新风机且两者之间设有室内第一电子膨胀阀；所述室内机设有室内换热器,所述新风机设有新风第一换热器和新风第二换热器；室外机模块,包括室外换热器、压缩机、四通阀和室外电子膨胀阀,并通过管路与室内机模块连接,其通过室外电子膨胀阀与所述新风机连接；控制模块内设有若干个控制方法；所述控制模块用于根据所述室内温度T-N与室外温度T-W、露点温度T-(Wl)的比较结果选择所述控制方法；所述控制模块还用于根据室内相对湿度φ选择所述控制方法。本发明通过空调室内机和新风处理装置的联动控制,解决了南方区域“回南天”气候条件下室内物体表面结露的问题,同时提高了的室内舒适性。(The invention discloses an air conditioning system comprising: the indoor unit module comprises an indoor unit and a fresh air fan, and an indoor first electronic expansion valve is arranged between the indoor unit and the fresh air fan; the indoor unit is provided with an indoor heat exchanger, and the fresh air fan is provided with a fresh air first heat exchanger and a fresh air second heat exchanger; the outdoor unit module comprises an outdoor heat exchanger, a compressor, a four-way valve and an outdoor electronic expansion valve and is connected with the indoor unit module through a pipeline,the fresh air fan is connected with the outdoor electronic expansion valve; a plurality of control methods are arranged in the control module; the control module is used for controlling the indoor temperature T according to the indoor temperature N And outdoor temperature T W Dew point temperature T Wl Selecting the control method according to the comparison result; the control module is further configured to select the control method based on the indoor relative humidity phi. The invention solves the problem of condensation on the surface of an indoor object in the 'backsouth sky' climate condition in the southern area by linkage control of the indoor unit of the air conditioner and the fresh air processing device, and simultaneously improves the indoor comfort.)

1. An air conditioning system, comprising:

the indoor unit module comprises an indoor unit and a fresh air fan, and an indoor first electronic expansion valve is arranged between the indoor unit and the fresh air fan;

the indoor unit is provided with an indoor heat exchanger, and the fresh air fan is provided with a fresh air first heat exchanger and a fresh air second heat exchanger;

the outdoor unit module comprises an outdoor heat exchanger, a compressor, a four-way valve and an outdoor electronic expansion valve and is connected with the indoor unit module through a pipeline;

control module for acquiring indoor temperature T_NAnd outdoor temperature T_W(ii) a And also for calculating the dew point temperature T of the outdoor air_WlAnd indoor relative humidity phi;

a plurality of control methods are arranged in the control module;

the control module is used for controlling the indoor temperature T according to the indoor temperature_NAnd outdoor temperature T_WDew point temperature T_WlSelecting the control method according to the comparison result;

the control module is further configured to select the control method based on the indoor relative humidity phi.

2. The air conditioning system of claim 1, wherein an indoor second electronic expansion valve is disposed between the fresh air first heat exchanger and the fresh air second heat exchanger; a first electromagnetic valve is arranged between the fresh air first heat exchanger and the outdoor electronic expansion valve; a second electromagnetic valve is arranged between the indoor four-way valve and the outdoor four-way valve; and the outdoor four-way valve and the two ends of the outdoor electronic expansion valve are connected in parallel with a third electromagnetic valve.

3. Air conditioning system according to claim 2, characterized in that when the indoor temperature T is above_NSatisfy T_N≥T_WThen, the control module selects a control method A; in the control method A, the outdoor heat exchanger is an evaporator, the fresh air first heat exchanger and/or the fresh air second heat exchanger is a condenser, and the indoor heat exchanger is closed.

4. Air conditioning system according to claim 2, characterized in that when the indoor temperature T is above_NSatisfy T_Wl<T_N<T_WThen, the control module selects a control method B; and in the control method B, the indoor heat exchanger is a condenser, the fresh air first heat exchanger or the fresh air second heat exchanger is an evaporator, the outdoor heat exchanger is closed, and the fresh air second heat exchanger or the fresh air first heat exchanger is closed.

5. Air conditioning system according to claim 2, characterized in that when the indoor temperature T is above_NSatisfy T_N≤T_WlThen, the control module selects a control method C; and in the control method C, the indoor heat exchanger is a condenser, the fresh air first heat exchanger or the fresh air second heat exchanger is a condenser, the fresh air second heat exchanger or the fresh air first heat exchanger is an evaporator, and the outdoor heat exchanger is closed.

6. The air conditioning system of claim 2, wherein the control module selects control method D when the indoor relative humidity Φ satisfies Φ ≧ 90%; in the control method D, the indoor heat exchanger is an evaporator, the fresh air first heat exchanger and the fresh air second heat exchanger are evaporators, and the outdoor heat exchanger is a condenser.

7. The air conditioning system according to claim 3, wherein in the control method a, the state of the indoor first electronic expansion valve is closed, and the state of the indoor second electronic expansion valve is closed or fully opened; the first electromagnetic valve is opened or closed; the second electromagnetic valve is opened; the third electromagnetic valve is closed; the outdoor electronic expansion valve is opened to play the role of throttling and reducing pressure.

8. The air conditioning system of claim 4, wherein in the control method B, the indoor first electronic expansion valve is in an open state and functions as a throttling pressure reduction, and the indoor second electronic expansion valve is in a closed state; the first electromagnetic valve and the third electromagnetic valve are opened; the second electromagnetic valve is closed; the outdoor electronic expansion valve is in a closed state.

9. The air conditioning system of claim 5, wherein in the control method C, the indoor first electronic expansion valve is fully open, and the indoor second electronic expansion valve is open, thereby performing throttling and pressure reduction; the first electromagnetic valve and the second electromagnetic valve are closed; the third electromagnetic valve is opened; the outdoor electronic expansion valve is in a closed state.

10. The air conditioning system of claim 6, wherein in the control method D, the indoor first electronic expansion valve and the indoor second electronic expansion valve are in a fully open state; the first electromagnetic valve, the second electromagnetic valve and the third electromagnetic valve are closed; the outdoor electronic expansion valve is opened to play the role of throttling and reducing pressure.

Technical Field

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

Background

"Huiyun" is the name of a weather phenomenon in south China, and generally refers to the phenomenon that the temperature begins to rise and the humidity begins to rise in spring every year. The south China is a typical marine subtropical monsoon climate, so that the south wind blown from the south sea brings warm and humid air to meet with cold air flow in the north of the continent in march to april every year to form a static frontal surface, so that the south China is cloudy and very humid and occasionally has little rain or heavy fog. Generally, the duration is about 1-2 months.

CN109323391B discloses a control method, a control device and an air conditioner for the south returning day, the invention provides a method for judging the south returning day, and the collection of the temperature and the humidity of the ground of an indoor wall surface is increased. The invention only considers indoor dehumidification and does not control indoor comfort.

In view of the above, it is desirable to design an air conditioning system to solve the above problems.

Disclosure of Invention

In order to solve the problems in the prior art, the invention provides an air conditioning system, which improves the indoor comfort and solves the problem of condensation on the surface of an indoor object in the southern area under the weather condition of 'return to south' by the linkage control of an indoor unit of an air conditioner and a fresh air processing device.

In order to achieve the purpose, the invention adopts the following technical scheme:

an air conditioning system comprising

The indoor unit module comprises an indoor unit and a fresh air fan, and an indoor first electronic expansion valve is arranged between the indoor unit and the fresh air fan;

the indoor unit is provided with an indoor heat exchanger, and the fresh air fan is provided with a fresh air first heat exchanger and a fresh air second heat exchanger;

the outdoor unit module comprises an outdoor heat exchanger, a compressor, a four-way valve and an outdoor electronic expansion valve and is connected with the indoor unit module through a pipeline;

control module for acquiring indoor temperature T_NAnd outdoor temperature T_W(ii) a And also for calculating the dew point temperature T of the outdoor air_WlAnd indoor relative humidity phi;

a plurality of control methods are arranged in the control module;

the control module is used for controlling the indoor temperature T according to the indoor temperature_NAnd outdoor temperature T_WDew point temperature T_WlSelecting the control method according to the comparison result;

the control module is further configured to select the control method based on the indoor relative humidity phi.

In some embodiments of the present invention, an indoor second electronic expansion valve is disposed between the fresh air first heat exchanger and the fresh air second heat exchanger; a first electromagnetic valve is arranged between the fresh air first heat exchanger and the outdoor electronic expansion valve; a second electromagnetic valve is arranged between the indoor four-way valve and the outdoor four-way valve; and the outdoor four-way valve and the two ends of the outdoor electronic expansion valve are connected in parallel with a third electromagnetic valve.

In some embodiments of the invention, when the indoor temperature T is lower than the predetermined temperature_NSatisfy T_N≥T_WThen, the control module selects a control method A; in the control method A, the outdoor heat exchanger is an evaporator, the fresh air first heat exchanger and/or the fresh air second heat exchanger is a condenser, and the indoor heat exchanger is closed.

In some embodiments of the invention, when the indoor temperature T is lower than the predetermined temperature_NSatisfy T_Wl<T_N<T_WThen, the control module selects a control method B; the control method B is that the indoor heat exchanger is a condenser, the fresh air first heat exchanger or the fresh air second heat exchanger is an evaporator, the outdoor heat exchanger is closed, and the fresh air second heat exchanger or the fresh air station is closedThe fresh air first heat exchanger.

In some embodiments of the invention, when the indoor temperature T is lower than the predetermined temperature_NSatisfy T_N≤T_WlThen, the control module selects a control method C; and in the control method C, the indoor heat exchanger is a condenser, the fresh air first heat exchanger or the fresh air second heat exchanger is a condenser, the fresh air second heat exchanger or the fresh air first heat exchanger is an evaporator, and the outdoor heat exchanger is closed.

In some embodiments of the present invention, the control module selects control method D when the indoor relative humidity φ satisfies φ ≧ 90%; in the control method D, the indoor heat exchanger is an evaporator, the fresh air first heat exchanger and the fresh air second heat exchanger are evaporators, and the outdoor heat exchanger is a condenser.

In some embodiments of the present invention, in the control method a, the state of the indoor first electronic expansion valve is closed, and the state of the indoor second electronic expansion valve is closed or fully opened; the first electromagnetic valve is opened or closed; the second electromagnetic valve is opened; the third electromagnetic valve is closed; the outdoor electronic expansion valve is opened to play the role of throttling and reducing pressure.

In some embodiments of the present invention, in the control method B, the state of the indoor first electronic expansion valve is open to perform the function of throttling and depressurizing, and the state of the indoor second electronic expansion valve is closed; the first electromagnetic valve and the third electromagnetic valve are opened; the second electromagnetic valve is closed; the outdoor electronic expansion valve is in a closed state.

In some embodiments of the present invention, in the control method C, the state of the indoor first electronic expansion valve is fully open, and the state of the indoor second electronic expansion valve is open, which functions as throttling and pressure reduction; the first electromagnetic valve and the second electromagnetic valve are closed; the third electromagnetic valve is opened; the outdoor electronic expansion valve is in a closed state.

In some embodiments of the invention, in the control method D, the indoor first electronic expansion valve and the indoor second electronic expansion valve are in a fully open state; the first electromagnetic valve, the second electromagnetic valve and the third electromagnetic valve are closed; the outdoor electronic expansion valve is opened to play the role of throttling and reducing pressure.

Compared with the prior art, the technical scheme of the invention has the following technical effects:

the invention uses the linkage control of the indoor machine of the air conditioner and the fresh air processing device, namely, the opening and closing of the indoor heat exchanger, the outdoor heat exchanger and the fresh air machine heat exchanger are correspondingly adjusted according to the change of the temperature and the humidity of the 'return south sky', and the flow direction of the refrigerant is controlled by using each electromagnetic valve and each electronic expansion valve; the problem of indoor object surface dewing under the weather condition of 'return to south' in southern areas is solved, and indoor comfort is improved.

Drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings needed to be used in the description of the embodiments are briefly introduced below, and it is obvious that the drawings in the following description are only some embodiments of the present invention, and it is obvious for those skilled in the art to obtain other drawings based on these drawings without creative efforts.

Fig. 1 is a selection flowchart of the control method of the air conditioning system.

Fig. 2 is a cycle chart of the air conditioning system in the control method a 1.

Fig. 3 is a cycle chart of the air conditioning system in the control method a 2.

Fig. 4 is a cycle chart of the air conditioning system in the control method B.

Fig. 5 is a cycle chart of the air conditioning system in the control method C.

Fig. 6 is a cycle chart of the air conditioning system in the control method D.

Reference numerals: 100-indoor heat exchanger; 210-a fresh air first heat exchanger; 220-fresh air second heat exchanger; 310-indoor four-way valve; 320-outdoor four-way valve; 400-an outdoor heat exchanger; 500-gas-liquid separator; 600-a compressor; 700-outdoor electronic expansion valve; 810-a first solenoid valve; 820-a second solenoid valve; 830-a third solenoid valve; 910-indoor first electronic expansion valve; 920-indoor second electronic expansion valve.

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, 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 invention.

In the description of the present invention, it is to be understood that the terms "center", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", and the like indicate orientations or positional relationships based on those shown in the drawings, and are only for convenience of description and simplicity of description, and do not indicate or imply that the referenced devices or elements must have a particular orientation, be constructed and operated in a particular orientation, and thus, are not to be construed as limiting the present invention.

In the description of the present invention, it should be noted that the terms "mounted," "connected," and "connected" are to be construed broadly and may be, for example, fixedly connected, detachably connected, or integrally connected unless otherwise explicitly stated or limited. The specific meanings of the above terms in the present invention can be understood in specific cases to those skilled in the art. In the foregoing description of embodiments, the particular features, structures, materials, or characteristics may be combined in any suitable manner in any one or more embodiments or examples.

The terms "first", "second" and "first" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of the present invention, "a plurality" means two or more unless otherwise specified.

The air conditioner performs a refrigeration cycle of the air conditioner by using a compressor, a condenser, an expansion valve, and an evaporator in the present application. The refrigeration cycle includes a series of processes involving compression, condensation, expansion, and evaporation, and supplies refrigerant to the air that has been conditioned and heat-exchanged.

The compressor compresses a refrigerant to a high-temperature and high-pressure state and discharges a compressed refrigerant gas. The discharged refrigerant gas flows into the condenser. The condenser condenses the compressed refrigerant into a liquid phase, and heat is released to the surrounding environment through the condensation process.

The expansion valve expands the liquid-phase refrigerant in a high-temperature and high-pressure state condensed in the condenser into a low-pressure liquid-phase refrigerant. The evaporator evaporates the refrigerant expanded in the expansion valve and returns the refrigerant gas in a low-temperature and low-pressure state to the compressor. The evaporator can achieve a cooling effect by heat-exchanging with a material to be cooled using latent heat of evaporation of a refrigerant. The air conditioner can adjust the temperature of the indoor space throughout the cycle.

The outdoor unit of the air conditioner refers to a portion of a refrigeration cycle including a compressor and an outdoor heat exchanger, the indoor unit of the air conditioner includes an indoor heat exchanger, and an expansion valve may be provided in the indoor unit or the outdoor unit.

First, a continuous cryogenic process must be performed for at least three days or more to bring the temperature of the indoor objects down to the same level as the outdoor, so-called "complete cold penetration". "at this time, the weather suddenly changed, the warm and humid air flow in south increased, and the outdoor temperature rose rapidly (the" dew point "of the air also rose rapidly). At this time, the temperature of the indoor object also rises, but far behind the rate at which the outdoor temperature rises. The expansion of the external temperature difference causes the temperature of the indoor objects to be lower than the air 'dew point', and the phenomenon of 'returning to south' occurs.

Referring to fig. 1, after the air conditioning system is started, the control module firstly detects whether the daily average air temperature is lower than 12 ℃ for three consecutive days, and if so, then judges whether the indoor relative humidity phi is obviously increased for three consecutive days, and the indoor relative humidity phi is more than or equal to 70%, and if the above conditions are all met, the indication that the coming of the coming south is about to be made.

Referring to fig. 2, the air conditioning system includes:

the indoor unit module comprises an indoor unit and a fresh air fan, and an indoor first electronic expansion valve is arranged between the indoor unit and the fresh air fan;

the indoor unit is provided with an indoor heat exchanger 100, and the fresh air fan is provided with a fresh air first heat exchanger 210 and a fresh air second heat exchanger 220;

an outdoor unit module including an outdoor heat exchanger 400, a compressor 600, an outdoor four-way valve 320 and an outdoor electronic expansion valve 700, and connected to the indoor unit module through a pipe;

control module for acquiring indoor temperature T_NAnd outdoor temperature T_W(ii) a And also for calculating the dew point temperature T of the outdoor air_WlAnd indoor relative humidity phi;

a plurality of control methods are arranged in the control module;

the control module is used for controlling the indoor temperature T according to the indoor temperature_NAnd outdoor temperature T_WDew point temperature T_WlSelecting the control method according to the comparison result;

the control module is further configured to select the control method based on the indoor relative humidity phi.

In some embodiments of the present invention, an indoor second expansion valve 920 is disposed between the fresh air first heat exchanger 210 and the fresh air second heat exchanger 220, and the indoor second expansion valve 920 is configured to be opened when two heat exchangers of the fresh air machine are used simultaneously; a first electromagnetic valve 810 is arranged between the fresh air first heat exchanger 210 and the outdoor electronic expansion valve 700; a second electromagnetic valve 820 is arranged between the indoor four-way valve 310 and the outdoor four-way valve 320; the outdoor four-way valve 320 is connected in parallel with the third solenoid valve 830 at both ends of the outdoor electronic expansion valve 700.

In some embodiments of the present invention, referring to FIG. 1, when the indoor temperature T is higher than the room temperature T_NSatisfy T_N≥T_WIn time, the temperature of the fresh air is increased and the relative humidity of the fresh air is reduced, so that the indoor comfort is improvedSex; and simultaneously, the indoor air temperature is properly increased.

The control module selects a control method A; the control method a is specifically divided into a control method a1 and a control method a 2.

[ control method A1 ]

In order to save energy, the indoor unit is closed at the moment, and only the heating mode of the fresh air machine is started. The outdoor heat exchanger 400 is an evaporator, the fresh air first heat exchanger 210 or the fresh air second heat exchanger 220 is a condenser, and the fresh air second heat exchanger 220 or the fresh air first heat exchanger 210 is closed; the indoor heat exchanger 100 is turned off.

In some embodiments of the present invention, referring to fig. 2, in this embodiment, the fresh air first heat exchanger 210 is a condenser and the fresh air second heat exchanger 220 is turned off. In the control method a1, the indoor first electronic expansion valve 910 is in a closed state, and the indoor second electronic expansion valve 920 is in a closed state; the first solenoid valve 810 is open; the second solenoid valve 820 is open; the third solenoid valve 830 is closed; the outdoor electronic expansion valve 700 is opened to perform throttling and pressure reducing functions.

In some embodiments of the present invention, the high-temperature and high-pressure gas refrigerant discharged from the compressor 600 reaches the second solenoid valve 820 through the outdoor four-way valve 320, and because the indoor first electronic expansion valve 910 is closed, the high-temperature and high-pressure gas refrigerant directly reaches the indoor four-way valve 310, and then enters the fresh air first heat exchanger 210 of the fresh air fan, exchanges heat with fresh air in the fresh air first heat exchanger 210, and becomes a low-temperature and high-pressure gas refrigerant, and because the indoor second electronic expansion valve 920 is also closed, the high-temperature and high-pressure gas refrigerant directly flows to the outdoor electronic expansion valve 700 of the outdoor unit through the first solenoid valve 810, and is throttled and depressurized by the outdoor electronic expansion valve 700 to become a low-; then flows to the outdoor heat exchanger 400, flows to the gas-liquid separator 500 through the outdoor four-way valve 320 again, and finally returns to the compressor 600 to complete one cycle.

Processing of fresh air in control method a 1: outdoor fresh air enters the fresh air machine from the outdoor, is heated by the fresh air first heat exchanger 210, rises in temperature, and then is sent into the indoor.

[ control method A2 ]

In order to save energy, the indoor unit is closed at the moment, and the quick heating mode of the fresh air fan is started. The outdoor heat exchanger 400 is an evaporator, the fresh air first heat exchanger 210 and the fresh air second heat exchanger 220 are condensers, and the indoor heat exchanger 100 is closed.

In some embodiments of the present invention, referring to fig. 3, in this embodiment, both the fresh air first heat exchanger 210 and the fresh air second heat exchanger 220 are condensers. In the control method a2, the indoor first electronic expansion valve 910 is in a closed state, and the indoor second electronic expansion valve 920 is in a fully open state; the first solenoid valve 810 is closed; the second solenoid valve 820 is open; the third solenoid valve 830 is closed; the outdoor electronic expansion valve 700 is opened to perform throttling and pressure reducing functions.

In some embodiments of the present invention, the high-temperature and high-pressure gas refrigerant discharged from the compressor 600 reaches the second solenoid valve 820 through the outdoor four-way valve 320, and because the indoor first electronic expansion valve 910 is closed, the high-temperature and high-pressure gas refrigerant directly reaches the indoor four-way valve 310, and then enters the fresh air first heat exchanger 210 of the fresh air fan, and exchanges heat with the fresh air processed by the fresh air second heat exchanger 220 in the fresh air first heat exchanger 210; because the indoor second electronic expansion valve 920 is opened, the fresh air flows to the fresh air second heat exchanger 220 through the indoor second electronic expansion valve 920, and fresh air introduced outdoors in the fresh air second heat exchanger 220 exchanges heat to become a low-temperature high-pressure gas refrigerant; the refrigerant returns to the outdoor electronic expansion valve 700 of the outdoor unit through the indoor four-way valve 310 again, and the throttle pressure of the outdoor electronic expansion valve 700 is reduced to become a low-temperature and low-pressure gas-liquid two-phase refrigerant; then flows to the outdoor heat exchanger 400, flows to the gas-liquid separator 500 through the outdoor four-way valve 320 again, and finally returns to the compressor 600 to complete one cycle.

Processing of fresh air in control method a 2: outdoor fresh air enters the fresh air machine from the outdoor, is heated by the fresh air second heat exchanger 220 to rise in temperature, is heated by the fresh air first heat exchanger 210 to rise in temperature, and is sent to the indoor.

In the control methods a1 and a2, the indoor unit can also perform heating operation, in which case the first electronic expansion valve 910 is opened, the second electromagnetic valve 820 is closed, and the indoor heat exchanger 100 functions as a condenser. And therefore will not be described in detail herein.

[ control method B ]

In some embodiments of the invention, with continued reference to FIG. 1, when the room temperature T is above the predetermined temperature T_NSatisfy T_Wl<T_N<T_WWhen the indoor temperature is lower than the outdoor temperature but higher than the dew point temperature of outdoor air, the indoor temperature rise speed is lower than the outdoor temperature, which indicates that the temperature is coming soon in the south, and the indoor unit heats to improve the indoor temperature and increase the indoor comfort; the new fan dehumidifies and reduces the moisture entering the room, and reduces the indoor humidity. The control module selects a control method B; in the control method B, the indoor heat exchanger 100 is a condenser, the fresh air first heat exchanger 210 or the fresh air second heat exchanger 220 is an evaporator, the outdoor heat exchanger 400 is closed, and the fresh air second heat exchanger 220 or the fresh air first heat exchanger 210 is closed.

In some embodiments of the present invention, referring to fig. 4, the fresh air first heat exchanger 210 is an evaporator and the fresh air second heat exchanger 220 is turned off. In the control method B, the indoor first electronic expansion valve 910 is opened to perform throttling and pressure reducing functions, and the indoor second electronic expansion valve 920 is closed; the first solenoid valve 810 and the third solenoid valve 830 are opened; the second solenoid valve 820 is closed; the outdoor electronic expansion valve 700 is in a closed state.

The high-temperature and high-pressure gas refrigerant discharged from the compressor 600 passes through the outdoor four-way valve 320, and the second electromagnetic valve 820 is closed, so that the high-temperature and high-pressure gas refrigerant reaches the indoor heat exchanger 100, exchanges heat with indoor air in the indoor heat exchanger 100, and is changed into a low-temperature and high-pressure gas refrigerant; then the refrigerant is throttled and cooled by the indoor first electronic expansion valve 910 to become a low-temperature low-pressure liquid refrigerant, the refrigerant enters the fresh air first heat exchanger 210 after reaching the indoor four-way valve 310, the refrigerant exchanges heat with outdoor fresh air to become a low-temperature low-pressure gas refrigerant, and the refrigerant sequentially passes through the first electromagnetic valve 810 and the third electromagnetic valve 830, flows into the gas-liquid separator 500 and finally returns to the compressor 600 because the indoor second electronic expansion valve 920 is closed and the outdoor electronic expansion valve 700 is also closed, thereby completing one cycle.

In the control method B, the fresh air treatment process comprises the following steps: outdoor fresh air enters the fresh air machine from the outside, is cooled by the fresh air first heat exchanger 210, and meanwhile, because the temperature of the fresh air first heat exchanger 210 is lower than the dew point temperature of the outdoor air, moisture in the outdoor air is condensed when meeting with the condensation, so that the humidity is reduced, and then the outdoor fresh air is sent into the room.

[ control method C ]

In some embodiments of the invention, with continued reference to FIG. 1, when the room temperature T is above the predetermined temperature T_NSatisfy T_N≤T_WlWhen the indoor temperature is lower than the dew point temperature of outdoor air, the climate in the south has entered, and the indoor unit heats to improve the indoor temperature and increase the indoor comfort; the fresh air machine does not cool and dehumidify, reduces the moisture entering the room and simultaneously ensures the temperature of the fresh air sent in. The control module selects a control method C; and in the control method C, the indoor heat exchanger is a condenser, the fresh air first heat exchanger or the fresh air second heat exchanger is a condenser, the fresh air second heat exchanger or the fresh air first heat exchanger is an evaporator, and the outdoor heat exchanger is closed.

In some embodiments of the present invention, referring to fig. 5, the fresh air first heat exchanger 210 is a condenser, and the fresh air second heat exchanger 220 is an evaporator, in the control method C, the indoor first electronic expansion valve 910 is fully opened, and the indoor second electronic expansion valve 920 is opened, so as to perform the functions of throttling and reducing pressure; the first solenoid valve 810 and the second solenoid valve 820 are closed; the third solenoid valve 830 is open; the outdoor electronic expansion valve 700 is in a closed state.

The second solenoid valve 820 is closed, so that the high-temperature and high-pressure gas refrigerant discharged from the compressor 600 reaches the indoor heat exchanger 100 through the outdoor four-way valve 320, and exchanges heat with indoor air in the indoor heat exchanger 100; then, the fresh air enters the fresh air first heat exchanger 210 after reaching the indoor four-way valve 310 through the indoor first electronic expansion valve 910, and exchanges heat with outdoor fresh air to become a low-temperature high-pressure gas refrigerant; because the outdoor second electronic expansion valve 920 is opened, and is throttled and depressurized, the liquid refrigerant which is changed into low-temperature and low-pressure liquid refrigerant enters the fresh air second heat exchanger 220 to exchange heat with outdoor fresh air, the liquid refrigerant is changed into low-temperature and low-pressure gas refrigerant, and the gas refrigerant passes through the indoor four-way valve 310 again, and because the first electromagnetic valve 810 and the outdoor electronic expansion valve 700 are both closed, the gas refrigerant passes through the third electromagnetic valve 830, flows into the gas-liquid separator 500, and finally returns to the compressor 600, thereby completing one cycle.

In the control method C, the fresh air treatment process comprises the following steps: outdoor fresh air enters the fresh air machine from the outside, is cooled by the fresh air second heat exchanger 220, and is sent to the inside of a room after being heated by the fresh air first heat exchanger 210 because the surface temperature of the fresh air second heat exchanger 220 is lower than the dew point temperature of the outdoor air, and the temperature and the humidity are both reduced because the moisture in the outdoor air meets the condensation and is accumulated.

[ control method D ]

In some embodiments of the present invention, with continued reference to fig. 1, when the indoor relative humidity Φ satisfies Φ ≥ 90%, the unit directly enters a deep dehumidification mode, and both the indoor unit and the fresh air unit dehumidify; when the indoor relative humidity phi is less than or equal to 70 percent, the unit automatically switches to the control method B. The control module selects a control method D; in the control method D, the indoor heat exchanger 100 is an evaporator, the fresh air first heat exchanger 210 and the fresh air second heat exchanger 220 are evaporators, and the outdoor heat exchanger 400 is a condenser.

In some embodiments of the present invention, referring to fig. 6, the fresh air first heat exchanger 210 is a second stage evaporator, and the fresh air second heat exchanger 220 is a first stage evaporator. In the control method D, the indoor first electronic expansion valve 910 and the indoor second electronic expansion valve 920 are fully opened; the first solenoid valve 810, the second solenoid valve 820 and the third solenoid valve 830 are closed; the outdoor electronic expansion valve 700 is opened to perform throttling and pressure reducing functions.

The high-temperature and high-pressure gas refrigerant exhausted by the compressor 600 reaches the outdoor heat exchanger 400 through the outdoor four-way valve 320, exchanges heat with outdoor air in the outdoor heat exchanger 400, becomes a low-temperature and high-pressure gas refrigerant, and then is throttled and reduced in pressure by the outdoor electronic expansion valve 700, and becomes a low-temperature and low-pressure liquid refrigerant; because the first electromagnetic valve 810 and the third electromagnetic valve 830 are in a closed state, the low-temperature and low-pressure liquid refrigerant reaches the indoor four-way valve 310 and then firstly enters the fresh air second heat exchanger 220 to exchange heat with outdoor fresh air for the first time; the air passes through the indoor second electronic expansion valve 920 in the fully-opened state to reach the fresh air first heat exchanger 210, and then carries out second heat exchange with outdoor fresh air, and because the second electromagnetic valve is in the closed state, the air enters the indoor heat exchanger 100 through the indoor four-way valve 310 and the indoor first electronic expansion valve 910 in the fully-opened state, and exchanges heat with indoor air to become a low-temperature and low-pressure gas refrigerant; finally through the outdoor four-way valve 310 → back to the gas-liquid separator 500 and finally back to the compressor 600, completing one cycle.

In the control method D, the fresh air treatment process comprises the following steps: outdoor fresh air enters the fresh air machine from the outside, is cooled for the first time through the fresh air second heat exchanger 220, and is cooled because the surface temperature of the fresh air second heat exchanger 220 is lower than the dew point temperature of the outdoor air, so that the moisture in the outdoor air is condensed when meeting the condensation, the temperature and the humidity are both reduced, then is cooled through the fresh air first heat exchanger 210, the temperature and the humidity are reduced again, and finally the fresh air is sent into the room.

Compared with the prior art, the technical scheme of the invention has the following technical effects:

the invention uses the linkage control of the indoor machine of the air conditioner and the fresh air processing device, namely, the opening and closing of the indoor heat exchanger, the outdoor heat exchanger and the fresh air machine heat exchanger are correspondingly adjusted according to the change of the temperature and the humidity of the 'return south sky', and the flow direction of the refrigerant is controlled by using each electromagnetic valve and each electronic expansion valve; the problem of indoor object surface dewing under the weather condition of 'return to south' in southern areas is solved, and indoor comfort is improved.

In the foregoing description of embodiments, the particular features, structures, materials, or characteristics may be combined in any suitable manner in any one or more embodiments or examples.

The above description is only for the specific embodiments of the present invention, but the scope of the present invention is not limited thereto, and any changes or substitutions that can be easily conceived by those skilled in the art within the technical scope of the present invention are included in the scope of the present invention. Therefore, the protection scope of the present invention shall be subject to the protection scope of the claims.