Fresh air air conditioning system and control method thereof

Abstract

The present invention provides a fresh air air conditioning system and a control method thereof, wherein the fresh air air conditioning system comprises a compressor, a first outdoor heat exchanger, a second outdoor heat exchanger, an indoor heat exchanger, a four-way valve, a three-way valve, a first throttling element, and a second throttling element, wherein the first port of the four-way valve and the first port of the three-way valve are connected to the exhaust port of the compressor, the indoor heat exchanger, the first throttling element, and the second outdoor heat exchanger are connected in sequence between the second port of the three-way valve and the second port of the four-way valve, the second throttling element and the first outdoor heat exchanger are connected in sequence between one end of the first throttling element connected to the second outdoor heat exchanger and the fourth port of the four-way valve, the third port of the three-way valve and the third port of the four-way valve are connected to the air intake port of the compressor, and the fresh air is introduced into the room via the first outdoor heat exchanger. According to the present invention, the fresh air is precooled or preheated via the first outdoor heat exchanger before being introduced into the indoor space, effectively reducing the adverse fluctuations in the temperature of the indoor space caused by the introduction of the fresh air.

Description

Technical Field

[0001] The present invention belongs to the technical field of air conditioning, and in particular relates to a fresh air air conditioning system and a control method thereof. Background Art

[0002] Simply using air conditioning for cooling has the problem of high energy consumption. If natural cooling sources can be utilized and air conditioning and ventilation are combined in some cases, the air conditioning load can be reduced, energy saving can be achieved, and indoor air quality can be improved. Summary of the invention

[0003] Therefore, the present invention provides a fresh air air conditioning system and a control method thereof, in which outdoor fresh air is precooled or preheated via a first outdoor heat exchanger before being introduced into the indoor space, thereby effectively reducing the adverse temperature fluctuations of the indoor space caused by the introduction of fresh air.

[0004] In order to solve the above problems, the present invention provides a fresh air air-conditioning system, including a compressor, a first outdoor heat exchanger, a second outdoor heat exchanger, an indoor heat exchanger, a four-way valve, a three-way valve, a first throttling element, and a second throttling element. The first port of the four-way valve and the first port of the three-way valve are connected to the exhaust port of the compressor, and the indoor heat exchanger, the first throttling element, and the second outdoor heat exchanger are connected in sequence between the second port of the three-way valve and the second port of the four-way valve. The end of the first throttling element connected to the second outdoor heat exchanger is the first end, and the second throttling element and the first outdoor heat exchanger are connected in sequence between the first end and the fourth port of the four-way valve. The third port of the three-way valve and the third port of the four-way valve are connected to the intake port of the compressor, and outdoor fresh air can be introduced into the indoor space via the first outdoor heat exchanger.

[0005] Preferably, when the operation mode of the fresh air air conditioning system is the cooling mode, the first port of the four-way valve is connected to the second port, the third port is connected to the fourth port, and the second port of the three-way valve is connected to the third port; or,

[0006] When the operation mode of the fresh air air conditioning system is the heating mode, the first port of the four-way valve is connected to the fourth port, the second port is connected to the third port, and the first port of the three-way valve is connected to the second port; or

[0007] When the operation mode of the fresh air air conditioning system is the defrost mode, the first port of the four-way valve is connected to the second port, the third port is connected to the fourth port, and the first port of the three-way valve is connected to the second port.

[0008] Preferably, the first outdoor heat exchanger is located in a fresh air housing, a fresh air introduction channel is constructed on the fresh air housing, the fresh air introduction channel is located on the air outlet side of the first outdoor heat exchanger, and the outdoor fresh air enters the indoor space through the fresh air introduction channel.

[0009] Preferably, the fresh air introduction channel is constructed with a fresh air outlet connected to the indoor space and an exhaust outlet connected to the outdoor space. The fresh air introduction channel is also provided with a damper, and the damper can be controlled to move to block any one of the fresh air outlet and the exhaust outlet.

[0010] Preferably, a first humidifying device is provided at the fresh air outlet.

[0011] Preferably, the first humidifying device comprises a first wet membrane, a spray assembly, and a water storage component, wherein the water storage component is located below the first wet membrane.

[0012] Preferably, the spray assembly comprises a water pump and a spray pipe located above the first wet film, and the water pump can pump water from the water storage component into the spray pipe.

[0013] Preferably, a second humidifying device is provided on the air inlet side of the first outdoor heat exchanger; and / or a fresh air driving fan is also provided on the air inlet side of the first outdoor heat exchanger.

[0014] Preferably, the second humidifying device comprises a second wet film and a water receiving pan located below the second wet film, wherein the water receiving pan is used to receive defrost water from the second outdoor heat exchanger, and the second wet film can absorb the defrost water.

[0015] Preferably, the compressor, the second outdoor heat exchanger, the four-way valve, the three-way valve, the first throttling element, and the second throttling element are located in the outdoor casing, and the fresh air housing is located below the outdoor casing.

[0016] Preferably, the first throttle element is located in an outdoor environment.

[0017] The present invention also provides a control method for a fresh air air conditioning system, wherein the fresh air air conditioning system is the above-mentioned fresh air air conditioning system, comprising the following steps:

[0018] Determine whether heating conditions are met;

[0019] When the heating conditions are not met, the air humidity dw and enthalpy Hw of the outdoor space and the user's set air humidity ds and enthalpy Hs are obtained;

[0020] Determine the magnitude relationship between dw and ds and the magnitude relationship between Hw and Hs;

[0021] The fresh air air conditioning system is controlled to enter different operating modes according to the size relationship.

[0022] Preferably, the air humidity dw and enthalpy value Hw of the outdoor space, and the user's set air humidity ds and enthalpy value Hs are obtained by the following method:

[0023] The set temperature Ts, the set humidity RHs, the outdoor real-time temperature Tw, and the outdoor real-time humidity RHw are obtained, and the set air moisture content ds and the enthalpy value Hs of the user are calculated based on the set temperature Ts and the set humidity RHs, and the air moisture content dw and the enthalpy value Hw of the outdoor space are calculated based on the outdoor real-time temperature Tw and the outdoor real-time humidity RHw.

[0024] Preferably,

[0025] When dw≥ds, the fresh air air conditioning system is controlled to operate in cooling mode; or,

[0026] When dw<ds and Hw<Hs, the fresh air air conditioning system is controlled to operate in ventilation mode; or,

[0027] When dw<ds and Hw≥Hs, determine whether (Tw-Ts)×1.005) / ((ds-dw)×2.5) is less than η, where η is the multiple of the efficiency of removing sensible heat and latent heat of the fresh air air conditioning system.

[0028] When (Tw-Ts)×1.005) / ((ds-dw)×2.5)<η, the fresh air air conditioning system is controlled to operate in ventilation and dehumidification mode, or, when (Tw-Ts)×1.005) / ((ds-dw)×2.5)≥η, the fresh air air conditioning system is controlled to operate in cooling mode.

[0029] Preferably,

[0030] During the operation of the fresh air air conditioning system in the cooling mode, when fresh air needs to be introduced, the fresh air driving fan corresponding to the first outdoor heat exchanger is controlled to generate a first air volume to introduce outdoor fresh air into the indoor space; or,

[0031] When the fresh air air conditioning system operates in ventilation mode, the fresh air driving fan corresponding to the first outdoor heat exchanger is controlled to generate a second air volume, wherein the second air volume is greater than the first air volume; or

[0032] When the fresh air air conditioning system operates in a ventilation and dehumidification mode, the fresh air driving fan corresponding to the first outdoor heat exchanger is controlled to generate a second air volume, and the second air volume is greater than the first air volume.

[0033] Preferably,

[0034] During the operation of the fresh air air conditioning system in the cooling mode, when the first humidifying device is included and the indoor space needs to be humidified, the first humidifying device is controlled to operate humidification; or,

[0035] During the operation of the ventilation mode of the fresh air air conditioning system, the indoor real-time temperature Tn and the indoor real-time humidity RHn are detected and the corresponding indoor moisture content dn is obtained. When the difference between Tn, RHn, dn and Ts, RHs, ds respectively exceeds the corresponding preset difference, the fresh air driving fan is controlled to adjust the air volume, and the first humidifying device is controlled to operate humidification to achieve evaporative cooling of the introduced fresh air; or,

[0036] During the operation of the ventilation and dehumidification mode, the real-time indoor humidity RHn is detected and the indoor moisture content dn is obtained. When the difference between RHn, dn and RHs, ds respectively exceeds the corresponding preset difference, the fresh air driving fan is controlled to adjust the air volume.

[0037] Preferably,

[0038] When the heating conditions are met, controlling the fresh air air conditioning system to operate in a heating mode;

[0039] During the operation of the heating mode, when fresh air needs to be introduced, the fresh air driving fan corresponding to the first outdoor heat exchanger is controlled to generate a first air volume to introduce outdoor fresh air into the indoor space; or,

[0040] During the operation of the heating mode, when a first humidifying device is included and the indoor space needs to be humidified, the first humidifying device is controlled to operate humidification; or,

[0041] During operation in the heating mode, when defrosting is required, the fresh air air conditioning system is controlled to operate in the defrost mode. When a fresh air introduction channel is included and a fresh air outlet and an exhaust port are constructed on the fresh air introduction channel, the fresh air outlet is controlled to be closed and the exhaust port to be opened at the same time.

[0042] The present invention provides a fresh air air conditioning system and a control method thereof, wherein outdoor fresh air is pre-cooled or preheated via a first outdoor heat exchanger before being introduced into an indoor space, thereby improving the quality of indoor air and effectively reducing adverse fluctuations in the temperature of the indoor space caused by the introduction of fresh air. BRIEF DESCRIPTION OF THE DRAWINGS

[0043] Figure 1 A schematic diagram of the principle of a fresh air air conditioning system according to an embodiment of the present invention;

[0044] Figure 2 for Figure 1 Schematic diagram of refrigerant flow direction of the fresh air air conditioning system in cooling mode (the hollow arrows in the figure show the refrigerant flow direction, and the solid arrows show the fresh air flow direction);

[0045] Figure 3 for Figure 1Schematic diagram of refrigerant flow direction of the fresh air air conditioning system in the heating mode (the hollow arrows in the figure show the refrigerant flow direction, and the solid arrows show the fresh air flow direction);

[0046] Figure 4 for Figure 1 Schematic diagram of refrigerant flow direction of the fresh air air conditioning system in the defrost mode (the hollow arrows in the figure show the refrigerant flow direction, and the solid arrows show the fresh air flow direction);

[0047] Figure 5 A schematic diagram of the principle of a fresh air air conditioning system according to another embodiment of the present invention;

[0048] Figure 6 for Figure 1 A schematic diagram of the structure of the fresh air device in FIG.

[0049] Figure 7 It is a schematic diagram of the assembly of the fresh air device and the outdoor unit of the air conditioning system;

[0050] Figure 8 for Figure 1 A schematic structural diagram of the first humidifying device in FIG.

[0051] Fig. 9 for Figure 8 Left view of;

[0052] Fig.10 Schematic diagram of the control flow of the control method of the fresh air air conditioning system according to an embodiment of the present invention.

[0053] The reference numerals are:

[0054] 1. Compressor; 21. First outdoor heat exchanger; 22. Second outdoor heat exchanger; 3. Indoor heat exchanger; 41. Four-way valve; 42. Three-way valve; 51. First throttling element; 52. Second throttling element; 6. First humidifying device; 61. First wet film; 62. Spray assembly; 621. Spray pipe; 622. Water pump; 63. Water storage component; 7. Second humidifying device; 71. Second wet film; 72. Water receiving tray; 8. Fresh air drive fan; 81. Filter; 100. Outdoor housing; 200. Fresh air housing; 201. Fresh air introduction channel; 202. Fresh air outlet; 203. Exhaust outlet; 204. Air door. DETAILED DESCRIPTION

[0055] See also Figures 1 to 10As shown, according to an embodiment of the present invention, a fresh air air conditioning system is provided, including a compressor 1, a first outdoor heat exchanger 21, a second outdoor heat exchanger 22, an indoor heat exchanger 3, a four-way valve 41, a three-way valve 42, a first throttling element 51, and a second throttling element 52. The first port of the four-way valve 41 and the first port of the three-way valve 42 are connected to the exhaust port of the compressor 1, and the indoor heat exchanger 3, the first throttling element 51, and the second outdoor heat exchanger 22 are connected in sequence between the second port of the three-way valve 42 and the second port of the four-way valve 41. The end of the first throttling element 51 connected to the second outdoor heat exchanger 22 is the first end, and the second throttling element 52 and the first outdoor heat exchanger 21 are connected in sequence between the first end and the fourth port of the four-way valve 41. The third port of the three-way valve 42 and the third port of the four-way valve 41 are connected to the air intake port of the compressor 1, and outdoor fresh air can be introduced into the indoor space via the first outdoor heat exchanger 21. In this technical solution, outdoor fresh air is pre-cooled or preheated through the first outdoor heat exchanger before being introduced into the indoor space, which can improve the quality of indoor air and effectively reduce the adverse fluctuations in the temperature of the indoor space caused by the introduction of fresh air.

[0056] The fresh air air conditioning system switches between various operation modes of the fresh air air conditioning system by controlling the on-off of the four-way valve 41 and the three-way valve 42. For example, when the operation mode of the fresh air air conditioning system is the cooling mode, the first port of the four-way valve 41 is connected to the second port, the third port is connected to the fourth port, and the second port of the three-way valve 42 is connected to the third port. Figure 2 As shown, at this time, the first outdoor heat exchanger 21 and the indoor heat exchanger 3 act as evaporators, and the second outdoor heat exchanger 22 acts as a condenser. When fresh air is introduced, the fresh air is pre-cooled at the first outdoor heat exchanger 21 and then introduced; or, when the operation mode of the fresh air air-conditioning system is the heating mode, the first port of the four-way valve 41 is connected to the fourth port, the second port is connected to the third port, and the first port of the three-way valve 42 is connected to the second port, as shown in FIG. Figure 3 As shown, at this time, the first outdoor heat exchanger 21 and the indoor heat exchanger 3 act as a condenser, and the second outdoor heat exchanger 22 acts as an evaporator. When fresh air is introduced, the fresh air is preheated at the first outdoor heat exchanger 21 and then introduced; or, when the operation mode of the fresh air air-conditioning system is the defrost mode, the first port of the four-way valve is connected to the second port, the third port is connected to the fourth port, and the first port of the three-way valve 42 is connected to the second port, as shown in FIG. Figure 4 As shown, at this time, the second outdoor heat exchanger 22 and the indoor heat exchanger 3 act as condensers, and the first outdoor heat exchanger 21 acts as an evaporator. In this operating mode, fresh air is not introduced, and the indoor space is continuously heated during the defrosting process (that is, continuous indoor heating can be achieved during defrosting in winter), thereby improving the heating comfort.

[0057] In some embodiments, the first outdoor heat exchanger 21 is located in the fresh air housing 200, and a fresh air introduction channel 201 is configured on the fresh air housing 200. The fresh air introduction channel 201 is located at the air outlet side of the first outdoor heat exchanger 21, and the outdoor fresh air enters the indoor space through the fresh air introduction channel 201. In this technical solution, the first outdoor heat exchanger 21 is located in the fresh air housing 200, that is, it exists independently of the outdoor casing 100, so that the first outdoor heat exchanger 21 and the fresh air housing 200 together form a fresh air device, so that they can exist as one component and can be flexibly installed according to the actual installation space.

[0058] In some embodiments, the fresh air introduction channel 201 is configured with a fresh air outlet 202 communicating with the indoor space and an exhaust outlet 203 communicating with the outdoor space, and a damper 204 is further provided in the fresh air introduction channel 201, and the damper 204 can be controlled to move to block any one of the fresh air outlet 202 and the exhaust outlet 203. Specifically, when the fresh air air conditioning system is in the heating mode or the cooling mode, when the indoor space needs to introduce fresh air, the damper 204 is controlled to close the exhaust outlet 203 and open the fresh air outlet 202, so as to achieve the synchronous introduction of fresh air; and when the fresh air air conditioning system is in the defrosting mode, the damper 204 is controlled to open the exhaust outlet 203 and close the fresh air outlet 202, so as to prevent the fresh air cooled by the first outdoor heat exchanger 21 from entering the indoor space and causing the indoor temperature to drop.

[0059] In some embodiments, a first humidifying device 6 is provided at the fresh air outlet 202. By disposing the first humidifying device 6 at the fresh air outlet 202, on the one hand, the introduced fresh air can be humidified in winter, and on the other hand, in summer and transitional seasons (spring and autumn), the evaporative cooling of water can be utilized to reduce the temperature of the introduced fresh air, thereby reducing the heat load of the indoor space, reducing the start-up and operation time of the air-conditioning system, and achieving the purpose of reducing energy consumption.

[0060] Preferably, the first humidifying device 6 is arranged at a position of the fresh air outlet 202 corresponding to the indoor side, so as to facilitate the user to fill the first humidifying device 6 with water. As a specific implementation, the first humidifying device 6 includes a first wet film 61, a spray assembly 62, and a water storage component 63, wherein the water storage component 63 is located below the first wet film 61 so as to be able to collect the water sprayed by the spray assembly 62 for reuse. The spray assembly 62 includes a water pump 622 and a spray pipe 621 located above the first wet film 61, and the water pump 622 can pump water from the water storage component 63 to the spray pipe 621. The water storage component 63 is provided with a corresponding water level switch so as to detect the water level therein and guide the user to fill water in time; the water storage component 63 is also provided with an overflow pipe to overflow the excess water.

[0061] In some embodiments, a second humidifying device 7 is provided on the air inlet side of the first outdoor heat exchanger 21. Specifically, the second humidifying device 7 includes a second wet film 71 and a water receiving tray 72 located below the second wet film 71, wherein the water receiving tray 72 is used to receive the defrost water of the second outdoor heat exchanger 22, and the second wet film 71 can absorb the defrost water, so that the defrost water can be collected to humidify the outdoor fresh air when the second outdoor heat exchanger 22 defrosts in winter. At the same time, the defrost water does not need to be discharged to avoid the water pipe from bursting due to freezing. It is worth emphasizing that in order to prevent the temperature of the outdoor fresh air from being too low after passing through the second wet film 71, the second humidifying device 7 in the present invention is arranged on the air inlet side of the first outdoor heat exchanger 21, so that the outdoor fresh air can be preheated after being humidified before entering the indoor space, thereby ensuring the comfort of indoor personnel.

[0062] The outdoor fresh air relies on the fresh air driving fan 8 to form flow power. Preferably, the fresh air driving fan 8 is arranged on the air inlet side of the first outdoor heat exchanger 21. The fresh air driving fan 8 can specifically be a centrifugal fan. Preferably, a filter 81 is provided at its air inlet.

[0063] Preferably, the first throttling element 51 is in an outdoor environment. At this time, the schematic diagram of the fresh air air conditioning system is as follows: Figure 5 As shown, in the related art, based on the precise control of the refrigerant flow rate, the first throttling element 51 is mostly installed on the indoor side, but it will cause the volume of the indoor unit to increase and there will be throttling noise. In this technical solution, the first throttling element 51 is set on the outdoor side, which can reduce the volume of the indoor unit and reduce the throttling noise.

[0064] It can be understood that the compressor 1, the second outdoor heat exchanger 22, the four-way valve 41, the three-way valve 42, the first throttling element 51, and the second throttling element 52 are all located in the outdoor housing 100. At this time, the fresh air housing 200 is located below the outdoor housing 100, and the water receiving pan 72 is arranged corresponding to the lower area of ​​the second outdoor heat exchanger 22, so that the defrosted water formed when the second outdoor heat exchanger 22 defrosts can flow into the water receiving pan 72 by its own weight, which is convenient for the use of the defrosted water. In some cases, the fresh air housing 200 can also be located above the outdoor housing 100, and the defrosted water formed at this time needs to be pumped and transferred by a power device such as a water pump.

[0065] According to an embodiment of the present invention, a control method for a fresh air air conditioning system is also provided, wherein the fresh air air conditioning system is the above-mentioned fresh air air conditioning system, comprising the following steps:

[0066] Determine whether the heating conditions are met (the specific heating conditions are the same as those of conventional air conditioners, such as Ts-Tn≥1°C and Tw≤30°C, Tw is the outdoor real-time temperature, Tn is the indoor real-time temperature, Ts is the user-set temperature, and of course other determination conditions may also be used, which are not particularly limited in the present invention);

[0067] When the heating conditions are not met, the air humidity dw and enthalpy Hw of the outdoor space and the user's set air humidity ds and enthalpy Hs are obtained;

[0068] Determine the magnitude relationship between dw and ds and the magnitude relationship between Hw and Hs;

[0069] The fresh air air conditioning system is controlled to enter different operating modes according to the size relationship.

[0070] In this technical solution, when the fresh air air-conditioning device meets the heating conditions, the relationship between the air humidity content and enthalpy value of the outdoor space and the set air humidity content and enthalpy value is further judged, and the fresh air air-conditioning system is controlled to enter different operating modes according to their respective relationship, so that outdoor fresh air can be introduced into the room when the humidity content and enthalpy value meet a certain relationship, thereby reducing the indoor heat load (dehumidification, cooling), thereby reducing the operating time of the air-conditioning system, and achieving the purpose of energy saving and consumption reduction.

[0071] Specifically, when dw≥ds, it means that the air humidity of the outdoor environment is high. If fresh air is introduced at this time, the heat / humidity of the indoor space will be aggravated, which will be disadvantageous for temperature regulation and energy saving. Therefore, the fresh air air conditioning system can be directly controlled to operate in the cooling mode. During the operation of the fresh air air conditioning system in the cooling mode, when the first humidifying device 6 is included and the indoor space needs to be humidified, the first humidifying device 6 is controlled to operate humidification, so as to increase the humidity of the indoor air conditioning and thus improve the user comfort.

[0072] When dw<ds and Hw<Hs, the fresh air air conditioning system is controlled to operate in ventilation mode, and the fresh air driving fan 8 corresponding to the first outdoor heat exchanger 21 is controlled to generate a second air volume, and the second air volume is greater than the first air volume. At this time, the humidity content and enthalpy value of the fresh air in the outdoor space are both less than the corresponding set values. At this time, the outdoor fresh air can be introduced into the indoor space, thereby reducing the heat / humidity load of the indoor space, reducing the start-up time of the air conditioning system, and achieving the purpose of reducing energy consumption; during the operation of the fresh air air conditioning system in ventilation mode, the indoor The real-time indoor temperature Tn, the real-time indoor humidity RHn and the corresponding indoor moisture content dn are obtained. When the differences between Tn, RHn, dn and Ts, RHs, ds respectively exceed the corresponding preset differences (the corresponding judgment means are well known in the industry and are not particularly limited here), the fresh air driving fan 8 is controlled to adjust the air volume, and the first humidifying device 6 is controlled to run humidification (that is, the spray pipe 621 is controlled to spray water onto the first wet film 61), so that the fresh air can flow through the wet film before entering the indoor space, thereby realizing evaporative cooling of the introduced fresh air.

[0073] When dw<ds and Hw≥Hs, that is, when the humidity content of outdoor fresh air is lower than the set air humidity content, but the enthalpy value of outdoor air is not lower than the set air enthalpy value, further judge whether (Tw-Ts)×1.005) / ((ds-dw)×2.5) is less than η, where η is the multiple of the efficiency of removing sensible heat and latent heat of the fresh air air-conditioning system (η can be calculated according to the test data of the unit, usually 2-3). When (Tw-Ts)×1.005) / ((ds-dw)×2.5)<η, the fresh air air-conditioning system is controlled to operate in ventilation and dehumidification mode, that is, the higher enthalpy value of outdoor air is used to reduce the humidity in the indoor space, so as to achieve the purpose of reducing energy consumption. When (Tw-Ts)×1.005) / ((ds-dw)×2.5)≥η, the fresh air air-conditioning system is controlled to operate in cooling mode.

[0074] In some embodiments, the air humidity dw and enthalpy value Hw of the outdoor space, and the user's set air humidity ds and enthalpy value Hs are obtained by the following method:

[0075] The set temperature Ts, the set humidity RHs, the outdoor real-time temperature Tw, and the outdoor real-time humidity RHw are obtained, and the set air moisture content ds and the enthalpy value Hs of the user are calculated based on the set temperature Ts and the set humidity RHs. The air moisture content dw and the enthalpy value Hw of the outdoor space are calculated based on the outdoor real-time temperature Tw and the outdoor real-time humidity RHw. The specific calculation method is existing and the present invention does not specifically limit it.

[0076] In some embodiments, during the operation of the fresh air air conditioning system in the cooling mode, when fresh air needs to be introduced (the specific determination method can be a common method, for example, a corresponding air quality sensor is set to detect the indoor air quality. When the indoor air quality is lower than a preset quality threshold, it is determined that fresh air needs to be introduced. As a conventional detection method in the industry, the present invention does not specifically limit it), the fresh air driving fan 8 corresponding to the first outdoor heat exchanger 21 is controlled to generate a first air volume to introduce outdoor fresh air into the indoor space. For example, the first air volume = (1-2) * room volume / h or 30m 3 / h·person; or,

[0077] During the operation of the ventilation and dehumidification mode of the fresh air air conditioning system, when ventilation and dehumidification are required (for example, the real-time indoor humidity RHn is detected and the corresponding indoor moisture content dn is obtained, and the difference between RHn and dn and RHs and ds is calculated. When the difference exceeds the corresponding preset difference, as a conventional technical means in the industry, the present invention does not specifically limit it), the fresh air driving fan 8 corresponding to the first outdoor heat exchanger 21 is controlled to generate a second air volume, for example, the second air volume = (3-5) * room volume. Preferably, the second air volume is greater than the first air volume, that is, under the demand based solely on air quality, a smaller amount of air volume is introduced to prevent adverse fluctuations in indoor temperature, and when based on reducing indoor heat / humidity loads, a larger amount of air volume is introduced, so that the low-humidity air outdoors can be used to cool / dehumidify the indoor air, thereby achieving the purpose of energy saving and consumption reduction.

[0078] When the heating conditions are met, the fresh air air conditioning system is controlled to operate in a heating mode;

[0079] During the operation of the heating mode, when fresh air needs to be introduced, the fresh air driving fan 8 corresponding to the first outdoor heat exchanger 21 is controlled to generate a first air volume (as described above) to introduce outdoor fresh air into the indoor space; or,

[0080] During the operation of the heating mode, when the first humidifying device 6 is included and the indoor space needs to be humidified (as described above), the first humidifying device 6 is controlled to operate humidification; or,

[0081] During the operation of the heating mode, when defrosting (for the second outdoor heat exchanger 22) is required (defrosting is an automatic control condition, the same as conventional air conditioning, specifically under the condition of Tw≤5℃, after the compressor has cumulatively run for 3 hours, it satisfies certain conditions and enters defrosting, or when the heating time continuously runs for more than 45 minutes, or the cumulative running time exceeds 90 minutes, it satisfies certain conditions and enters defrosting, and the present invention does not specifically limit it), the fresh air air conditioning system is controlled to run in the defrost mode, and when it includes a fresh air introduction channel 201 and the fresh air introduction channel 201 is constructed with a fresh air outlet 202 and an exhaust outlet 203, the fresh air outlet 202 is controlled to be closed and the exhaust outlet 203 is controlled to be opened at the same time.

[0082] It should be noted that the moisture content d and the enthalpy value H are both calculated based on temperature and humidity. The moisture content is the absolute value of water content in the air (g / kg of dry air), and the relative humidity is a relative value. The calculation method is well known in the industry; the difference and function of small air volume (the first air volume) fresh air and large air volume (the second air volume) fresh air: small air volume ventilation is used to solve indoor air quality problems, such as excessive concentration of pollutants such as CO2, which is the preset air volume. At this time, the air volume can be = (1~2)*room volume / h or 30m3 / h·person; large air volume ventilation is mainly used to reduce indoor heat and humidity load, that is, to send fresh air to the room for cooling or dehumidification. At this time, the air volume needs to be large enough to be useful. The initial air volume is preset, and then the air volume will be adjusted according to the actual working conditions. At this time, the air volume is preferably = (3~5)*room volume.

[0083] The following is combined with Fig.10 The control method of the present invention is further described:

[0084] (1) Turn on the computer.

[0085] (2) Read the user-set temperature and humidity or the default setting value (Ts, RHs), outdoor temperature and humidity (Tw, RHw), and indoor temperature and humidity (Tn, RHn).

[0086] (3) Compare the indoor and outdoor temperatures to determine whether the heating conditions are met. If so, enter the attached Figure 3 In the heating cycle shown, when fresh air is needed (user instructions or automatic control are both possible, and the automatic control can be automatically turned on when the indoor CO2 concentration exceeds a certain value), a small air volume ventilation is turned on (such as air volume = (1-2)*room volume / h or 30m3 / h·person); when humidification is needed (such as RHn<RHs), the fan of the ventilation device and the water injection valve and water pump of the humidification device are turned on; when defrosting is needed, the attached air flow is turned on. Figure 4 Defrost cycle shown.

[0087] (4) If the heating conditions are not met, the built-in program calculates the outdoor air humidity (dw) and enthalpy (Hw) based on the outdoor temperature and humidity, and calculates the set humidity (ds) and enthalpy (Hw) based on the set temperature and humidity.

[0088] (5) If dw ≥ ds, then directly run the attached Figure 2 The refrigeration cycle shown runs according to the compressor control program based on the relationship between Ts, Tn and RHs, RHn. When fresh air is needed, small air volume ventilation (such as (1~2)*room volume or 30m3 / h·person) is turned on.

[0089] (6) If dw<ds, further determine whether Hw is less than Hs. If so, perform ventilation with large air volume (such as air volume = (3-5)*room volume) or ventilation and humidification (such as when RHn<RHs), compare the difference between the indoor temperature, humidity and moisture content (Tn, RHn, dn) and the set temperature, humidity and moisture content (Ts, RHs, ds), adjust the ventilation air volume, and open the water injection valve and water pump as needed.

[0090] (7) If Hw ≥ Hs, is it necessary to further determine whether (Tw-Ts)×1.005) / ((ds-dw)×2.5)<η? If this condition is met, high-volume ventilation and dehumidification are performed, and the difference between the indoor humidity (RHn) and / or moisture content (dn) and the set humidity (RHs) and / or moisture content (ds) is compared to adjust the ventilation volume. If this condition is not met, compressor cooling is performed, and according to the relationship between Ts, Tn and RHs, RHn, the compressor control program is operated (small-volume ventilation is turned on when fresh air is needed).

[0091] (8) Each mode runs according to the preset time. If the user shuts down the machine, the shutdown program will be executed. If the machine is not shut down, step (2) will be re-entered until the machine is shut down.

[0092] It is easy for those skilled in the art to understand that, under the premise of no conflict, the above-mentioned advantageous methods can be freely combined and superimposed.

[0093] The above are only preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention shall be included in the protection scope of the present invention. The above are only preferred embodiments of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and variations can be made without departing from the technical principles of the present invention, and these improvements and variations should also be regarded as the protection scope of the present invention.

Claims

1. A fresh air air conditioning system, characterized in that: The invention comprises a compressor (1), a first outdoor heat exchanger (21), a second outdoor heat exchanger (22), an indoor heat exchanger (3), a four-way valve (41), a three-way valve (42), a first throttling element (51), and a second throttling element (52), wherein the first port of the four-way valve (41) and the first port of the three-way valve (42) are connected to the exhaust port of the compressor (1), and the indoor heat exchanger (3), the first throttling element (51), and the second throttling element (52) are connected in sequence between the second port of the three-way valve (42) and the second port of the four-way valve (41). 51) and a second outdoor heat exchanger (22); the end at which the first throttling element (51) is connected to the second outdoor heat exchanger (22) is the first end; the second throttling element (52) and the first outdoor heat exchanger (21) are connected in sequence between the first end and the fourth port of the four-way valve (41); the third port of the three-way valve (42) and the third port of the four-way valve (41) are connected to the air intake port of the compressor (1); and outdoor fresh air can be introduced into the indoor space via the first outdoor heat exchanger (21).

2. The fresh air air conditioning system according to claim 1, characterized in that: When the operation mode of the fresh air air conditioning system is the cooling mode, the first port of the four-way valve (41) is connected to the second port, the third port is connected to the fourth port, and the second port of the three-way valve (42) is connected to the third port; or, When the operation mode of the fresh air air conditioning system is the heating mode, the first port of the four-way valve (41) is connected to the fourth port, the second port is connected to the third port, and the first port of the three-way valve (42) is connected to the second port; or, When the operation mode of the fresh air air conditioning system is the defrost mode, the first port of the four-way valve is connected to the second port, the third port is connected to the fourth port, and the first port of the three-way valve (42) is connected to the second port.

3. The fresh air air conditioning system according to claim 1, characterized in that: The first outdoor heat exchanger (21) is located in a fresh air housing (200), and a fresh air introduction channel (201) is constructed on the fresh air housing (200). The fresh air introduction channel (201) is located on the air outlet side of the first outdoor heat exchanger (21), and the outdoor fresh air enters the indoor space through the fresh air introduction channel (201).

4. The fresh air air conditioning system according to claim 3, characterized in that: The fresh air introduction channel (201) is provided with a fresh air outlet (202) connected to the indoor space and an exhaust outlet (203) connected to the outdoor space. A damper (204) is also provided in the fresh air introduction channel (201). The damper (204) can be controlled to move so as to block any one of the fresh air outlet (202) and the exhaust outlet (203).

5. The fresh air air conditioning system according to claim 4, characterized in that: A first humidifying device (6) is provided at the fresh air outlet (202).

6. The fresh air air conditioning system according to claim 5, characterized in that: The first humidifying device (6) comprises a first wet membrane (61), a spray assembly (62), and a water storage component (63), wherein the water storage component (63) is located below the first wet membrane (61).

7. The fresh air air conditioning system according to claim 6, characterized in that: The spray assembly (62) comprises a water pump (622) and a spray pipe (621) located above the first wet film (61), and the water pump (622) is capable of pumping water from the water storage component (63) into the spray pipe (621).

8. The fresh air air conditioning system according to claim 3, characterized in that: A second humidifying device (7) is provided on the air inlet side of the first outdoor heat exchanger (21); and / or a fresh air driving fan (8) is also provided on the air inlet side of the first outdoor heat exchanger (21).

9. The fresh air air conditioning system according to claim 8, characterized in that: The second humidifying device (7) comprises a second wet film (71) and a water receiving pan (72) located below the second wet film (71), wherein the water receiving pan (72) is used to receive defrost water from the second outdoor heat exchanger (22), and the second wet film (71) is capable of absorbing the defrost water.

10. The fresh air air conditioning system according to claim 3, characterized in that: The compressor (1), the second outdoor heat exchanger (22), the four-way valve (41), the three-way valve (42), the first throttling element (51), and the second throttling element (52) are located in the outdoor casing (100), and the fresh air casing (200) is located below the outdoor casing (100).

11. The fresh air air conditioning system according to claim 1, characterized in that: The first throttle element (51) is located in the outdoor environment.

12. A control method for a fresh air air conditioning system, characterized in that: The fresh air air conditioning system is the fresh air air conditioning system according to any one of claims 1 to 11, comprising the following steps: Determine whether heating conditions are met; When the heating conditions are not met, the air humidity dw and enthalpy Hw of the outdoor space and the user's set air humidity ds and enthalpy Hs are obtained; Determine the magnitude relationship between dw and ds and the magnitude relationship between Hw and Hs; The fresh air air conditioning system is controlled to enter different operating modes according to the size relationship.

13. The control method according to claim 12, characterized in that: The air humidity dw and enthalpy Hw of the outdoor space, and the user's set air humidity ds and enthalpy Hs are obtained in the following way: The set temperature Ts, the set humidity RHs, the outdoor real-time temperature Tw, and the outdoor real-time humidity RHw are obtained, and the set air moisture content ds and the enthalpy value Hs of the user are calculated based on the set temperature Ts and the set humidity RHs, and the air moisture content dw and the enthalpy value Hw of the outdoor space are calculated based on the outdoor real-time temperature Tw and the outdoor real-time humidity RHw.

14. The control method according to claim 13, characterized in that: When dw≥ds, the fresh air air conditioning system is controlled to operate in cooling mode; or, When dw<ds and Hw<Hs, the fresh air air conditioning system is controlled to operate in ventilation mode; or, When dw<ds and Hw≥Hs, determine whether (Tw-Ts)×1.005) / ((ds-dw)×2.5) is less than η, where η is the multiple of the efficiency of removing sensible heat and latent heat of the fresh air air conditioning system. When (Tw-Ts)×1.005) / ((ds-dw)×2.5)<η, the fresh air air conditioning system is controlled to operate in ventilation and dehumidification mode, or, when (Tw-Ts)×1.005) / ((ds-dw)×2.5)≥η, the fresh air air conditioning system is controlled to operate in cooling mode.

15. The control method according to claim 14, characterized in that: When the fresh air air conditioning system is in a cooling mode, and fresh air needs to be introduced, the fresh air driving fan (8) corresponding to the first outdoor heat exchanger (21) is controlled to generate a first air volume to introduce outdoor fresh air into the indoor space; or, When the fresh air air conditioning system operates in a ventilation mode, a fresh air driving fan (8) arranged corresponding to the first outdoor heat exchanger (21) is controlled to generate a second air volume, wherein the second air volume is greater than the first air volume; or When the fresh air air conditioning system operates in a ventilation and dehumidification mode, the fresh air driving fan (8) arranged corresponding to the first outdoor heat exchanger (21) is controlled to generate a second air volume, and the second air volume is greater than the first air volume.

16. The control method according to claim 15, characterized in that: During the operation of the fresh air air conditioning system in the cooling mode, when the first humidifying device (6) is included and the indoor space needs to be humidified, the first humidifying device (6) is controlled to operate humidification; or, During the operation of the ventilation mode of the fresh air air conditioning system, the real-time indoor temperature Tn and the real-time indoor humidity RHn are detected and the corresponding indoor moisture content dn is obtained. When the difference between Tn, RHn, dn and Ts, RHs, ds respectively exceeds the corresponding preset difference, the fresh air driving fan (8) is controlled to adjust the air volume, and the first humidifying device (6) is controlled to operate humidification, so as to achieve evaporative cooling of the introduced fresh air; or, During the operation of the ventilation and dehumidification mode, the real-time indoor humidity RHn is detected and the indoor moisture content dn is obtained. When the difference between RHn, dn and RHs, ds respectively exceeds the corresponding preset difference, the fresh air driving fan (8) is controlled to adjust the air volume.

17. The control method of the fresh air air conditioning system according to claim 12, characterized in that: When the heating conditions are met, controlling the fresh air air conditioning system to operate in a heating mode; During operation in the heating mode, when fresh air needs to be introduced, the fresh air driving fan (8) arranged corresponding to the first outdoor heat exchanger (21) is controlled to generate a first air volume to introduce outdoor fresh air into the indoor space; or, During operation in the heating mode, when a first humidifying device (6) is included and the indoor space needs to be humidified, the first humidifying device (6) is controlled to operate humidification; or, During operation in the heating mode, when defrosting is required, the fresh air air conditioning system is controlled to operate in the defrost mode, and when a fresh air introduction channel (201) is included and a fresh air outlet (202) and an exhaust port (203) are configured on the fresh air introduction channel (201), the fresh air outlet (202) is controlled to be closed and the exhaust port (203) is controlled to be opened at the same time.

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