Fresh air humidity-adjustable multi-connected air conditioner

Abstract

The present application discloses a fresh air humidity control multi-split unit comprising: a plurality of humidity control indoor units; the humidity control indoor units comprising: a first air duct and a second air duct; a first fan disposed in the first air duct, a second fan disposed in the second air duct; a first heat exchanger coated with an adsorbent material disposed in the first air duct, a second heat exchanger coated with an adsorbent material disposed in the second air duct; in one state of the humidity control indoor units, the first fan functions as an exhaust fan, allowing return air to flow outdoors through the first air duct; the second fan functions as a supply fan, allowing fresh air to flow indoors through the second air duct; in another state, the first fan changes direction and functions as a supply fan, allowing fresh air to flow indoors through the first air duct; the second fan changes direction and functions as an exhaust fan, allowing return air to flow outdoors through the second air duct; an outdoor heat exchanger is connected in series between the exhaust port of the compressor and the D pipe of the four-way valve. The fresh air humidity control multi-split unit achieves continuous dehumidification and humidification by rotating the fans in both directions, without requiring an air valve switching device.

Description

Technical Field

[0001] The present application relates to the field of air treatment technology, and in particular to a fresh air humidity control multi-split unit. Background Art

[0002] Fresh air humidifiers are mainly used to introduce humidified fresh air into the room to regulate the indoor air. During summer dehumidification, the fresh air is cooled by the evaporator, and the moisture it carries is adsorbed on the adsorption material to dehumidify the fresh air; under certain conditions, the air duct is switched, the evaporator becomes a condenser, and the indoor return air is heated by the condenser, and then the moisture inside the adsorption material is dried out and taken away; during winter moisturizing, the principle is the opposite, the indoor return air is cooled by the evaporator, and the moisture it carries is adsorbed on the adsorption material for storage; under certain conditions, the air duct is switched, the evaporator becomes a condenser, and the fresh air is heated by the condenser, and the moisture on the adsorption material is dried out and sent to the room to humidify the fresh air;

[0003] In the above-mentioned fresh air humidifier, two air valve switching devices are required to switch the air duct, and the air valve switching devices are usually complex in structure and large in size. Summary of the Invention

[0004] The present application provides a fresh air humidity control multi-split unit, which realizes continuous dehumidification and humidification through the forward and reverse rotation of the fan, without the need for an air valve switching device.

[0005] A fresh air humidity control multi-split unit comprises: m humidity control indoor units, where m is greater than or equal to 2; the humidity control indoor units comprising: a first air duct and a second air duct, respectively connecting indoor and outdoor; a first fan and a second fan, the first fan being disposed in the first air duct and the second fan being disposed in the second air duct; a first heat exchanger and a second heat exchanger, both coated with an adsorption material, the first heat exchanger being disposed in the first air duct and the second heat exchanger being disposed in the second air duct;

[0006] The humidity control unit can realize the transformation of two states:

[0007] In one state, the first fan is used as a supply fan, so that fresh air flows into the room through the first air duct; the second fan is used as an exhaust fan, so that return air flows into the room through the second air duct;

[0008] When changing from one state to another, the first fan changes direction and acts as an exhaust fan, so that the return air flows to the outside through the first air duct; the second fan changes direction and acts as a supply fan, so that the fresh air flows to the room through the second air duct;

[0009] Wherein, in each humidity control indoor unit, the first heat exchanger and the second heat exchanger are connected in series to form a heat exchange branch;

[0010] The fresh air humidity control multi-split system also includes: a compressor and a four-way valve;

[0011] The two ends of the heat exchange branch are respectively connected to the C pipe and E pipe of the four-way valve, and the air intake of the compressor is connected to the S pipe of the four-way valve; an outdoor heat exchanger is connected in series between the exhaust port of the compressor and the D pipe of the four-way valve.

[0012] In some embodiments, there are m four-way valves; the heat exchange branches are connected to the four-way valves in a one-to-one correspondence, and the exhaust port of the compressor is connected in series with the outdoor heat exchanger and then connected to the D pipe of each four-way valve.

[0013] In some embodiments, it also includes: a first solenoid valve, which is connected in parallel with the outdoor heat exchanger between the exhaust port of the compressor and the D pipe of the four-way valve; a reversing valve, connected between the compressor and the outdoor heat exchanger, the D pipe of the reversing valve is connected to the exhaust port of the compressor, the C pipe of the reversing valve is connected to the outdoor heat exchanger, the S pipe of the reversing valve is connected to the suction port of the compressor, and the E pipe of the reversing valve is blocked; a one-way valve, which is connected in series between the outdoor heat exchanger and the D pipe of the four-way valve; a second solenoid valve, one end of which is connected to the S pipe of the four-way valve, and the other end is connected between the outdoor heat exchanger and the one-way valve; a third solenoid valve, which is connected in series between the S pipe of the four-way valve and the suction port of the compressor.

[0014] In some embodiments, the system further includes: a controller configured to: in the dehumidification mode, determine whether Pd≥α or doa-ds≥X1 is established; if so, control the first solenoid valve to be disconnected, connect the D and C pipes of the reversing valve, disconnect the second solenoid valve, and connect the third solenoid valve; if not, control the first solenoid valve to be connected, connect the D and E pipes of the reversing valve, disconnect the second solenoid valve, and connect the third solenoid valve;

[0015] Wherein, Pd represents the exhaust pressure of the compressor, doa represents the outdoor absolute humidity, ds represents the set indoor absolute humidity; α and X1 are preset values.

[0016] In some embodiments, the system further includes: a controller configured to: in the humidification mode, determine whether Ps < β or doa-ds ≤ X2; if so, control the first solenoid valve to be connected, the D pipe and the E pipe of the reversing valve to be connected, the second solenoid valve to be connected, and the third solenoid valve to be disconnected; if not, control the first solenoid valve to be connected, the D pipe and the E pipe of the reversing valve to be connected, the second solenoid valve to be disconnected, and the third solenoid valve to be connected;

[0017] Wherein, Ps represents the exhaust pressure of the compressor, doa represents the outdoor absolute humidity, ds represents the set indoor absolute humidity; β and X2 are preset values.

[0018] In some embodiments, the system further includes: a temperature and humidity sensor for detecting the temperature Toa and humidity Hoa of the outdoor fresh air; a controller for calculating the absolute humidity doa of the outdoor fresh air based on Toa and Hoa, and controlling the frequency F×1 of the compressor based on the difference between doa and the set indoor absolute humidity ds;

[0019] In dehumidification mode,

[0020]

[0021] Among them, A, B, C, and n are constants; Q is the number of humidity control indoor units that are turned on, and M is the total number of humidity control indoor units.

[0022] In some embodiments, the system further includes: a temperature and humidity sensor for detecting the temperature Toa and humidity Hoa of the outdoor fresh air; a controller for calculating the absolute humidity doa of the outdoor fresh air based on Toa and Hoa, and controlling the frequency F×1 of the compressor based on the difference between doa and the set indoor absolute humidity ds;

[0023] In humidification mode,

[0024]

[0025] Where Toa represents the temperature of outdoor fresh air; A1, B1, C1, and n1 are constants; Q is the number of humidity control units that are turned on, and M is the total number of humidity control units.

[0026] In some embodiments, the system further includes: a temperature and humidity sensor for detecting outdoor temperature Toa and humidity Hoa, and indoor temperature Tra and humidity Hra; a controller for calculating outdoor absolute humidity doa based on the outdoor temperature and humidity, calculating indoor absolute humidity dra based on the indoor temperature and humidity, and calculating latent heat load Qq, sensible heat load Qx, and sensible heat factor SHF based on doa, dra, Toa, and Tra;

[0027] When SHF≥0.7, control the compressor frequency Fx1=A3×(SHF) 2 +TL / Te×(SHF);

[0028] Wherein, TL represents the gas pipe temperature detection value in the refrigerant circuit, Te represents the liquid pipe temperature detection value in the refrigerant circuit, and A3 is a constant.

[0029] In some embodiments, the controller is further configured to: when SHF < 0.3, control the switching time of the four-way valve to TH = A2 × (SHF) 2 +B2×(SHF);

[0030] Among them, A2 and B2 are constants.

[0031] In some embodiments, the latent heat load Qq, the sensible heat load Q×, and the sensible heat factor SHF are calculated according to the following formulas:

[0032] Qq=E×[Gρ×(doa-dra)];

[0033] Qx = Cm × [Gρ × (Toa-Tra)];

[0034] SHF=Qx / (Qx+Qq);

[0035] Among them, G is the air volume, ρ is the density, and E and Cm are constants. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] Figure 1 A schematic diagram of a humidity control unit in a fresh air humidity control multi-split system according to some embodiments is shown;

[0037] Figure 2 A schematic diagram showing a humidity control unit in a fresh air humidity control multi-split system in one state according to some embodiments is shown;

[0038] Figure 3 A schematic diagram showing a humidity control unit in a fresh air humidity control multi-split system in another state according to some embodiments is shown;

[0039] Figure 4 A schematic diagram of a fresh air humidity control multi-split unit according to some embodiments is shown;

[0040] Figure 5 Schematic diagrams of fresh air humidity control multi-split units according to other embodiments are shown;

[0041] Figure 6 Schematic diagrams of fresh air humidity control multi-split units according to further embodiments are shown;

[0042] Figure 7 A first state diagram of a fresh air humidity control multi-split system in a dehumidification mode according to some further embodiments is shown;

[0043] Figure 8 A second state diagram of the fresh air humidity control multi-split system in the dehumidification mode according to some further embodiments is shown;

[0044] Figure 9 Schematic diagram of the refrigerant circuit of the fresh air humidity control multi-split unit in dehumidification mode according to some other embodiments Figure 1 ;

[0045] Figure 10 Schematic diagram of the refrigerant circuit of the fresh air humidity control multi-split unit in dehumidification mode according to some other embodiments Figure 2 ;

[0046] Figure 11 A first state diagram of a fresh air humidity control multi-split system in a humidification mode according to yet other embodiments is shown;

[0047] Figure 12 A second state diagram of the fresh air humidity control multi-split system in the humidification mode according to yet other embodiments is shown;

[0048] Figure 13 Schematic diagram of the refrigerant circuit of the fresh air humidity control multi-split unit in humidification mode according to some other embodiments Figure 1 ;

[0049] Figure 14 Schematic diagram of the refrigerant circuit of the fresh air humidity control multi-split unit in humidification mode according to some other embodiments Figure 2 ;

[0050] In the above figures: 101, first humidity-control indoor unit; 102, second humidity-control indoor unit; 103, third humidity-control indoor unit; 1, casing; 11, first outdoor air outlet; 12, second outdoor air outlet; 13, first indoor air outlet; 14, second indoor air outlet; 21, first fan; 22, second fan; 3, first filter; 4, second filter; 5, first heat exchanger; 6, second heat exchanger; 7, compressor; 8, four-way valve; 9, electronic expansion valve; 10, outdoor heat exchanger; 200, first solenoid valve; 400, third solenoid valve; 500, second solenoid valve; 600, one-way valve. DETAILED DESCRIPTION

[0051] In order to make the purpose and implementation of this application clearer, the exemplary implementation of this application will be clearly and completely described below in conjunction with the drawings in the exemplary embodiments of this application. Obviously, the described exemplary embodiments are only part of the embodiments of this application, not all of the embodiments.

[0052] In the description of this application, it should be understood that the terms "center", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", etc., indicating the orientation or position relationship, are based on the orientation or position relationship shown in the accompanying drawings, and are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on this application.

[0053] The terms "first" and "second" are used for descriptive purposes only and should not be understood to indicate or imply relative importance or implicitly specify the number of the technical features indicated. Therefore, features specified as "first" or "second" may explicitly or implicitly include one or more of such features. In the description of this application, unless otherwise specified, "plurality" means two or more.

[0054] In the description of this application, it should be noted that, unless otherwise expressly specified or limited, the terms "mounted," "connected," and "connected" should be understood broadly. For example, they may refer to fixed, detachable, or integral connections; mechanical or electrical connections; direct or indirect connections through an intermediate medium; and internal communication between two components. Those skilled in the art will understand the specific meanings of the above terms in this application based on the specific circumstances.

[0055] The following describes the embodiments of the present application in detail with reference to the accompanying drawings.

[0056] According to the implementation manner of the present application, the fresh air humidity control multi-split system includes m humidity control indoor units, where m is a positive integer ≥2.

[0057] The following is an introduction to the humidity control indoor unit:

[0058] Reference Figures 1 to 3 The humidity control unit includes a housing 1, which forms the general appearance of the humidity control unit and is roughly rectangular in shape. The side wall of the housing 1 is provided with four air vents, namely a first outdoor air vent 11, a second outdoor air vent 12, a first indoor air vent 13, and a second indoor air vent 14.

[0059] The first outdoor air outlet 11 and the second outdoor air outlet 12 are connected to the outside through air ducts respectively, serving as the inlet of fresh air or the outlet of return air, and the first indoor air outlet 13 and the second indoor air outlet 14 are connected to the room through air ducts respectively, serving as the outlet of fresh air or the inlet of return air.

[0060] The air duct in the shell 1 is separated by a partition, and the air duct includes a first air duct and a second air duct. The first outdoor air outlet 11 and the first indoor air outlet 13 are connected to form the first air duct, and the second outdoor air outlet 12 and the second indoor air outlet 14 are connected to form the second air duct.

[0061] The humidity control indoor unit further includes a first fan 21 and a second fan 22. The first fan 21 is arranged in the first air duct, and the second fan 22 is arranged in the second air duct.

[0062] The humidity control unit can switch between two states:

[0063] In one state, in the first air duct, the first fan 21 rotates forward, and the outdoor fresh air enters the first air duct from the first outdoor air outlet 11 and is sent to the room through the first indoor air outlet 13; in the second air duct, the second fan 22 rotates reversely, and the indoor return air enters the second air duct from the second indoor air outlet 14 and is discharged to the outside through the second outdoor air outlet 12.

[0064] At this time, the first fan 21 is used as a fresh air fan, and the first air duct is used as a fresh air duct; the second fan 22 is used as an exhaust fan, and the second air duct is used as a return air duct.

[0065] In another state, in the first air duct, the first fan 21 rotates in reverse, and the indoor return air enters the first air duct from the first indoor air outlet 13 and is discharged to the outside through the first outdoor air outlet 11;

[0066] In the second air duct, the second fan 22 rotates forward, and outdoor fresh air enters the second air duct from the second outdoor air outlet 12 and is sent to the room through the second indoor air outlet 14.

[0067] At this time, the first fan 21 is used as an exhaust fan, and the first air duct is used as a return air duct; the second fan 22 is used as a supply fan, and the second air duct is used as a fresh air duct.

[0068] It should be noted that in this application, the forward and reverse rotation of the fan only refers to the opposite direction of rotation, and does not specifically refer to the forward and reverse rotation of the fan in actual working conditions.

[0069] Compared with the problems of complex structure and large size brought about by the use of two air valve switching devices to change the air duct in the prior art, the humidity-control indoor unit of the present application uses the forward and reverse rotation of the fan to achieve the conversion of the fresh air duct and the return air duct, omits the air valve switching device, simplifies the product structure, reduces costs, and makes the product smaller, saving space.

[0070] In addition, the omission of the air valve switching device reduces the internal resistance of the unit, improves the working efficiency of the unit, and reduces energy consumption.

[0071] According to an embodiment of the present application, the humidity control indoor unit further includes a first heat exchanger 5 and a second heat exchanger 6. The first heat exchanger 5 is disposed within the first air duct, and the second heat exchanger 6 is disposed within the second air duct. Both the first heat exchanger 5 and the second heat exchanger 6 are coated with an adsorbent material. When the first heat exchanger 5 functions as an evaporator, the second heat exchanger 6 functions as a condenser. When the first heat exchanger 5 functions as a condenser, the second heat exchanger 6 functions as an evaporator.

[0072] The heat exchanger, acting as an evaporator, cools the air and dries it by absorbing water through the adsorption action of the adsorbent material. The heat exchanger, acting as a condenser, humidifies the air by heating the adsorbent material and evaporating water from it through the regeneration action of the adsorbent material.

[0073] In the embodiment of the present application, the first air duct and the second air duct are symmetrical with respect to the transverse center of the housing 1 , so that the first air duct and the second air duct are completely identical.

[0074] Since the first air duct and the second air duct need to periodically switch between the fresh air duct and the exhaust air duct, if the two are different, it will cause obvious wind pressure inequality between the two, which will bring the risk of cross-wind, thereby reducing the working efficiency of the humidifier and increasing energy consumption.

[0075] A first filter 3 and a second filter 4 are further provided in the humidity control unit, wherein the first filter 3 is located in the first air duct and the second filter 4 is located in the second air duct, for filtering and purifying the circulating air.

[0076] The following is an introduction to the fresh air humidity control multi-split system using m=3 as an example:

[0077] Reference Figures 4 to 6 According to an embodiment of the present application, the fresh air humidity control multi-split unit includes a first humidity control indoor unit 101, a second humidity control indoor unit 102 and a third humidity control indoor unit 103.

[0078] In some embodiments, reference Figure 4 The refrigerant circuit of the fresh air humidity control multi-split unit shares an electronic expansion valve 9.

[0079] The exhaust port of the compressor 7 is connected to the D pipe of the four-way valve 8, and the intake port of the compressor 7 is connected to the S pipe of the four-way valve 8.

[0080] The first heat exchanger 5 of each humidity control indoor unit is connected in parallel between one end of the electronic expansion valve 9 and the E tube of the four-way valve 8, and the second heat exchanger 6 of each humidity control indoor unit is connected in parallel between the other end of the electronic expansion valve 9 and the C tube of the four-way valve 8.

[0081] In other embodiments, referring to Figure 5 There are m=3 electronic expansion valves. In each humidity control unit, an electronic expansion valve 9 is connected in series between the first heat exchanger 5 and the second heat exchanger 6 to form a heat exchange branch. The electronic expansion valve 9 can control the flow of the corresponding branch.

[0082] The exhaust port of the compressor 7 is connected to the D pipe of the four-way valve 8, the intake port of the compressor 7 is connected to the S pipe of the four-way valve 8, and the three heat exchange branches are connected in parallel between the C pipe and the E pipe of the four-way valve 8.

[0083] In the above two embodiments, when the four-way valve 8 is switched, the three humidity control indoor units need to change their states simultaneously.

[0084] In other embodiments, referring to Figure 6 The refrigerant circuit of the fresh air humidity control multi-split unit is provided with m=3 four-way valves 8.

[0085] The three four-way valves 8 are four-way valve (8-1), four-way valve (8-2), and four-way valve (8-3), which correspond one to one to the three humidity control indoor units.

[0086] In the refrigerant circuit, the exhaust port of the compressor 7 is connected to the D pipes of the four-way valves (8-1), (8-2), and (8-3), and the intake port of the compressor 7 is connected to the S pipes of the four-way valves (8-1), (8-2), and (8-3).

[0087] The E tube of the four-way valve (8-1) is connected in series with the first heat exchanger 5 of the first humidity control indoor unit 101, the electronic expansion valve (9-1), the second heat exchanger 6 of the first humidity control indoor unit 101, and the C tube of the four-way valve (8-1);

[0088] The E tube of the four-way valve (8-2) is connected in series with the first heat exchanger 5 of the second humidity control indoor unit 102, the electronic expansion valve (9-2), the second heat exchanger 6 of the second humidity control indoor unit 102, and the C tube of the four-way valve (8-2);

[0089] The E tube of the four-way valve (8-3) is connected in series with the first heat exchanger 5 of the third humidity control indoor unit 103, the electronic expansion valve (9-3), the second heat exchanger 6 of the third humidity control indoor unit 103, and the C tube of the four-way valve (8-3).

[0090] In the present application, multiple four-way valves are provided corresponding to multiple humidity control indoor units, so that the multiple humidity control indoor units can be independent of each other and can select the reversing time according to their own conditions without synchronous reversing, which is more intelligent.

[0091] According to an embodiment of the present application, the compressor 7 and three four-way valves 8 are arranged on the outdoor unit, and the shell 2 part is the indoor unit. In this way, the outdoor unit can be installed in the equipment room, avoiding the switching sound of the four-way valve 8 affecting the user experience.

[0092] In some embodiments of the present application, the refrigerant circuit further includes an outdoor heat exchanger 10. The outdoor heat exchanger 10 is connected in series between the exhaust port of the compressor 7 and the D pipe of the four-way valve 8.

[0093] When the outdoor temperature is high, since the air volume and area at the condenser in the indoor unit are small, it is very likely that the evaporation temperature in summer will be high and the dehumidification performance will be reduced due to insufficient condensation capacity. Therefore, the present application connects the outdoor heat exchanger 10 in series with the exhaust port of the compressor 7 to increase the cooling capacity of the system.

[0094] According to an embodiment of the present application, the refrigerant circuit further includes a first solenoid valve 200 , a reversing valve 8 - 0 , a second solenoid valve 500 , a third solenoid valve 400 and a one-way valve 600 .

[0095] The exhaust port of the compressor 7 is connected in series with the first solenoid valve 200 and then to the D pipe of the four-way valve 8;

[0096] The D pipe of the reversing valve 8-0 is connected to the exhaust port of the compressor 7. The C pipe of the reversing valve 8-0 is connected in series with the outdoor heat exchanger 10 and the one-way valve 600, and then connected to the D pipe of the four-way valve 8. The S pipe of the reversing valve 8-0 is connected to the suction port of the compressor 7. The E pipe of the reversing valve 8-0 is blocked.

[0097] The S-tube of the four-way valve 8 is connected in series with the second solenoid valve 500 and then connected to between the outdoor heat exchanger 10 and the one-way valve 600;

[0098] The S pipe of the four-way valve 8 is connected in series with the third solenoid valve 400 and then to the suction port of the compressor 7 .

[0099] In other embodiments, the reversing valve 8 - 0 may be replaced by a three-way valve.

[0100] One port of the three-way valve is connected to the outdoor heat exchanger 10, the second port of the three-way valve is connected to the exhaust port of the compressor 7, and the third port of the three-way valve is connected to the intake port of the compressor 7. When the second port and the first port of the three-way valve are connected, the refrigerant flows from the exhaust port of the compressor 7 to the outdoor heat exchanger 10, and the outdoor heat exchanger 10 functions as a condenser. When the first port and the third port of the three-way valve are connected, the refrigerant flows from the outdoor heat exchanger to the intake port of the compressor 7, and the outdoor heat exchanger 10 functions as an evaporator.

[0101] In other embodiments, the reversing valve 8 - 0 may be replaced by two solenoid valves: one solenoid valve is connected between the exhaust port of the compressor 7 and the outdoor heat exchanger 10 , and the other solenoid valve is connected between the outdoor heat exchanger 10 and the suction port of the compressor 7 .

[0102] <Summer Dehumidification Mode>

[0103] Reference Figure 2 and Figure 7 , first state: the first heat exchanger 5 is used as an evaporator, the second heat exchanger 6 is used as a condenser; the first fan 21 rotates forward and is used as a blower, and the second fan 22 rotates reverse and is used as an exhaust fan.

[0104] First air duct (fresh air duct): Fresh air enters through the first outdoor air outlet 11. Driven by the first fan 21, it is first purified by the first filter 3 and then passes through the first heat exchanger 5 (evaporator). The fresh air is cooled and dehumidified. The moisture in the fresh air is adsorbed by the adsorption material on the surface of the first heat exchanger 5 (adsorption process). The fresh air then reaches the first indoor air outlet 13 and is sent into the room, completing the fresh air dehumidification process.

[0105] Second air duct (return air duct): Indoor air enters through the second indoor air outlet 14, first passes through the second heat exchanger 6 (condenser), takes away the heat of the second heat exchanger 6 and the moisture in the adsorption material (regeneration process), then passes through the second filter 4 for purification, and then, driven by the second fan 22, finally reaches the second outdoor air outlet 12 and is discharged to the outside, completing one exhaust process.

[0106] There are two situations in the refrigerant circuit:

[0107] The first case: when the dehumidification load is not large, the outdoor heat exchanger 10 does not work.

[0108] First solenoid valve 200 Reversing valve 8-0 Second solenoid valve 500 The third solenoid valve 400 Open (connected) ON Close (disconnect) Open (connected)

[0109] The reversing valve 8 - 0 is in the ON state, that is, the D pipe of the reversing valve 8 - 0 is connected to the E pipe, and the C pipe is connected to the S pipe. At this time, since the D pipe is not connected to the C pipe, the exhaust port of the compressor 7 is not connected to the outdoor heat exchanger 10.

[0110] Reference Figure 9 The high-temperature and high-pressure refrigerant is delivered from the exhaust port of the compressor 7, passes through the first solenoid valve 200, and is then diverted to the three four-way valves 8 (all in the OFF state at this time, but the states may be inconsistent), and then flows to each humidity control indoor unit (the flow rate of each humidity control indoor unit is determined by 9-1, 9-2, and 9-3). The refrigerant reaches the second heat exchanger 6 of each humidity control indoor unit, transfers heat to the exhaust air, and the refrigerant becomes a low-temperature and high-pressure two-phase refrigerant, and then flows to the electronic expansion valve 9, is throttled and reduced in pressure to become a low-temperature and low-pressure liquid refrigerant, and then flows to the first heat exchanger 5 of each humidity control indoor unit, absorbs the heat of the air outside the pipe and becomes a low-temperature and low-pressure gaseous refrigerant, and then flows to the E pipes of the four-way valves (8-1, 8-2, 8-3) respectively, and then flows to the S pipe of the four-way valve 8 to the third solenoid valve 400, and returns to the compressor 7, thus completing a refrigerant cycle.

[0111] The second situation: when the dehumidification load is large, the outdoor heat exchanger 10 works.

[0112] First solenoid valve 200 Reversing valve 8-0 Second solenoid valve 500 The third solenoid valve 400 Close (disconnect) OFF Close (disconnect) Open (connected)

[0113] The reversing valve 8 - 0 is in the OFF state, that is, the D pipe of the reversing valve 8 - 0 is connected to the C pipe, and the E pipe is connected to the S pipe. At this time, since the D pipe is connected to the C pipe, the exhaust port of the compressor 7 is connected to the outdoor heat exchanger 10.

[0114] Reference Figure 10 The high-temperature, high-pressure refrigerant is delivered from the exhaust port of the compressor 7. It first passes through the reversing valve 8-0 and flows into the outdoor heat exchanger 10 (which acts as a condenser and dissipates heat to the air). Then, it passes through the one-way valve 600 and is divided into three four-way valves 8 (all in the OFF state at this time, but they can also be in different states). Then, it flows to each humidity control unit (the flow rate of each humidity control unit is determined by 9-1, 9-2, and 9-3). The refrigerant reaches the second heat exchanger 6 of each humidity control unit, transfers heat to the exhaust air, and becomes a low-temperature, high-pressure two-phase refrigerant. It then flows to the electronic expansion valve 9, where it is throttled and reduced in pressure to become a low-temperature, low-pressure liquid refrigerant. It then flows to the first heat exchanger 5 of each humidity control unit, absorbs heat from the air outside the pipe, and becomes a low-temperature, low-pressure gaseous refrigerant. Then, it flows to the E pipes of the four-way valves (8-1, 8-2, and 8-3), and then flows through the S pipe of the four-way valve 8 to the third solenoid valve 400, returning to the compressor 7, thus completing a refrigerant cycle.

[0115] In the second case, the outdoor heat exchanger 10 is used as a condenser, which can improve the cooling capacity of the system during dehumidification in summer to meet the cooling and dehumidification needs of the system under high outdoor temperature conditions.

[0116] When the state transition conditions are met, refer to Figure 8 , the four-way valve 8 is reversed, the first heat exchanger 5 is used as a condenser, and the second heat exchanger 6 is used as an evaporator; the first fan 21 is reversed and used as an exhaust fan, and the second fan 22 is forward rotated and used as a supply fan.

[0117] Second state

[0118] Second air duct (fresh air duct): Fresh air enters from the second outdoor air outlet 12. Driven by the second fan 22, it is first purified by the second filter 4 and then passes through the second heat exchanger 6 (evaporator). The fresh air is cooled and dehumidified. The moisture in the fresh air is adsorbed by the adsorption material on the surface of the second heat exchanger 6 (adsorption process). The fresh air then reaches the second indoor air outlet 14 and is sent into the room, completing the fresh air dehumidification process.

[0119] First air duct (exhaust duct): Indoor air enters through the first indoor air outlet 13, first passes through the first heat exchanger 5 (condenser), takes away the heat of the first heat exchanger 5 and the moisture in the adsorption material (regeneration process), then passes through the first filter 3 for purification, and then, driven by the first fan 21, finally reaches the first outdoor air outlet 11 and is discharged to the outside, completing one exhaust process.

[0120] There are two situations in the refrigerant circuit:

[0121] The first case: when the dehumidification load is not large, the outdoor heat exchanger 10 does not work.

[0122] First solenoid valve 200 Reversing valve 8-0 Second solenoid valve 500 The third solenoid valve 400 Open (connected) ON Close (disconnect) Open (connected)

[0123] The reversing valve 8 - 0 is in the ON state, that is, the D pipe of the reversing valve 8 - 0 is connected to the E pipe, and the C pipe is connected to the S pipe. At this time, since the D pipe is not connected to the C pipe, the exhaust port of the compressor 7 is not connected to the outdoor heat exchanger 10.

[0124] Reference Figure 9, Refrigerant circuit: The high-temperature and high-pressure refrigerant is delivered from the exhaust port of the compressor 7, first passes through the first solenoid valve 200, and then is divided into three four-way valves 8 (all in the ON state at this time, but the states can also be inconsistent), and then flows to each humidity control indoor unit (the flow rate of each humidity control indoor unit is determined by 9-1, 9-2, and 9-3). The refrigerant reaches the first heat exchanger 5 of each humidity control indoor unit, transfers heat to the exhaust air, and the refrigerant becomes a low-temperature and high-pressure two-phase refrigerant, and then flows to the electronic expansion valve 9, is throttled and reduced in pressure to become a low-temperature and low-pressure liquid refrigerant, and then flows to the second heat exchanger 6 of each humidity control indoor unit, absorbs the heat of the air outside the pipe and becomes a low-temperature and low-pressure gaseous refrigerant, and then flows to the C pipes of the four-way valves (8-1, 8-2, 8-3) respectively, and then flows through the S pipe of the four-way valve 8 to the third solenoid valve 400, and returns to the compressor 7, thus completing a refrigerant cycle.

[0125] The second situation: when the dehumidification load is large, the outdoor heat exchanger 10 works.

[0126] First solenoid valve 200 Reversing valve 8-0 Second solenoid valve 500 The third solenoid valve 400 Close (disconnect) OFF Close (disconnect) Open (connected)

[0127] The reversing valve 8 - 0 is in the OFF state, that is, the D pipe of the reversing valve 8 - 0 is connected to the C pipe, and the E pipe is connected to the S pipe. At this time, since the D pipe is connected to the C pipe, the exhaust port of the compressor 7 is connected to the outdoor heat exchanger 10.

[0128] Reference Figure 10 Refrigerant circuit: The high-temperature, high-pressure refrigerant is delivered from the exhaust port of the compressor 7. It first passes through the reversing valve 8-0 and flows into the outdoor heat exchanger 10 (which acts as a condenser and dissipates heat to the air). Then, it passes through the one-way valve 600 and is divided into three four-way valves 8 (all in the ON state at this time, but they can be in different states). Then, it flows to each humidity control unit (the flow rate of each humidity control unit is determined by 9-1, 9-2, and 9-3). The refrigerant reaches the first heat exchanger 5 of each humidity control unit, transfers heat to the exhaust air, and becomes a low-temperature, high-pressure two-phase refrigerant. It then flows to the electronic expansion valve 9, where it is throttled and reduced in pressure to become a low-temperature, low-pressure liquid refrigerant. It then flows to the second heat exchanger 6 of each humidity control unit, absorbs heat from the air outside the pipe, and becomes a low-temperature, low-pressure gaseous refrigerant. It then flows to the C pipes of the four-way valves (8-1, 8-2, and 8-3), and then through the S pipe of the four-way valve 8 to the third solenoid valve 400, returning to the compressor 7, thus completing a refrigerant cycle.

[0129] In this way, the dehumidification process continuously cycles between the first state and the second state.

[0130] <Winter Humidification Mode>

[0131] Reference Figure 11 , first state: the first heat exchanger 5 is used as a condenser, and the second heat exchanger 6 is used as an evaporator;

[0132] The first fan 21 rotates forward and serves as a blower, and the second fan 22 rotates reverse and serves as an exhaust fan.

[0133] First air duct (fresh air duct): Fresh air enters from the first outdoor air outlet 11. Driven by the first fan 21, it is first purified by the first filter 3 and then passes through the first heat exchanger 5 (condenser). The fresh air is heated and the moisture in the adsorption material on the surface of the first heat exchanger 5 is regenerated and mixed into the fresh air, increasing its humidity. The fresh air then reaches the first indoor air outlet 13 and is sent into the room, completing the fresh air humidification process.

[0134] Second air duct (exhaust duct): Indoor return air enters through the second indoor air outlet 14, first passes through the second heat exchanger 6 (evaporator), where it is cooled. At the same time, the moisture carried by the return air is adsorbed by the adsorption material on the surface of the second heat exchanger 6, thereby cooling and dehumidifying the return air. The return air is then purified by the second filter 4 and then driven by the second fan 22 to reach the second outdoor air outlet 12 and be discharged outdoors, completing one exhaust process.

[0135] There are two situations in the refrigerant circuit:

[0136] The first situation: when the humidification load is not large, the outdoor heat exchanger 10 does not work.

[0137] First solenoid valve 200 Reversing valve 8-0 Second solenoid valve 500 The third solenoid valve 400 Open (connected) ON Close (disconnect) Open (connected)

[0138] The reversing valve 8 - 0 is in the ON state, that is, the D pipe of the reversing valve 8 - 0 is connected to the E pipe, and the C pipe is connected to the S pipe. At this time, since the D pipe is not connected to the C pipe, the exhaust port of the compressor 7 is not connected to the outdoor heat exchanger 10.

[0139] Reference Figure 13 Refrigerant circuit: The high-temperature and high-pressure refrigerant is delivered from the exhaust port of the compressor 7, first passes through the first solenoid valve 200, and is then divided into three four-way valves 8 (at this time, it is in the ON state, and the states can also be inconsistent), and then flows to each humidity control indoor unit (the flow rate of each humidity control indoor unit is determined by 9-1, 9-2, and 9-3). The refrigerant reaches the first heat exchanger 5 of each humidity control indoor unit, transfers heat to the fresh air, and the refrigerant becomes a low-temperature and high-pressure two-phase refrigerant, and then flows to the electronic expansion valve 9, is throttled and reduced in pressure to become a low-temperature and low-pressure liquid refrigerant, and then flows to the second heat exchanger 6 of each humidity control indoor unit, absorbs the heat of the air outside the pipe and becomes a low-temperature and low-pressure gaseous refrigerant, and then flows to the C pipe of the four-way valve 8, and then from the S pipe of the four-way valve 8 through the third solenoid valve 400, back to the compressor 7, thus completing a refrigerant cycle.

[0140] The second situation: when the humidification load is large, the outdoor heat exchanger 10 is in operation.

[0141] First solenoid valve 200 Reversing valve 8-0 Second solenoid valve 500 The third solenoid valve 400 Open (connected) ON Open (connected) Close (disconnect)

[0142] The reversing valve 8-0 is in the ON state, that is, the D pipe of the reversing valve 8-0 is connected to the E pipe, and the C pipe is connected to the S pipe. At this time, since the D pipe is not connected to the C pipe, the exhaust port of the compressor 7 is not connected to the outdoor heat exchanger 10, and the outdoor heat exchanger 10 is connected to the intake port of the compressor 7.

[0143] Reference Figure 14 Refrigerant circuit: The high-temperature, high-pressure refrigerant is delivered from the exhaust port of the compressor 7, passes through the first solenoid valve 200, and is then divided into three four-way valves 8 (at this time, they are in the ON state, but the states can also be inconsistent). Then, it flows to each humidity control unit (the flow rate of each humidity control unit is determined by 9-1, 9-2, and 9-3). The refrigerant reaches the first heat exchanger 5 of each humidity control unit, transfers heat to the fresh air, and the refrigerant becomes a low-temperature, high-pressure two-phase refrigerant. It then flows to the electronic expansion valve 9, where it is throttled and reduced in pressure to become a low-temperature, low-pressure liquid refrigerant. It then flows to the second heat exchanger 6 of each humidity control unit, absorbs heat from the air outside the pipe, and becomes a low-temperature, low-pressure gaseous refrigerant. It then flows to the C pipe of the four-way valve 8, and then from the S pipe of the four-way valve 8 through the second solenoid valve 500 to the outdoor heat exchanger 10, where it continues to absorb heat from the air outside the pipe. It then returns to the compressor 7 through the reversing valve 8-0, thus completing one refrigerant cycle.

[0144] When the state transition conditions are met, refer to Figure 12 , the four-way valve 8 is reversed, the first heat exchanger 5 is used as an evaporator, and the second heat exchanger 6 is used as a condenser; the first fan 21 is reversed and used as an exhaust fan; the second fan 22 is forward rotated and used as a supply fan.

[0145] Second state:

[0146] Second air duct (fresh air duct): Fresh air enters from the second outdoor air outlet 12. Driven by the second fan 22, it is first purified by the second filter 4 and then passes through the second heat exchanger 6 (condenser). The fresh air is heated and the moisture in the adsorption material on the surface of the second heat exchanger 6 is regenerated and mixed with the fresh air, increasing its humidity. The fresh air then reaches the second indoor air outlet 14 and is sent into the room, completing the fresh air humidification process.

[0147] First air duct (exhaust duct): Indoor return air enters through the first indoor air outlet 13, passes through the first heat exchanger 5 (evaporator), and is cooled. At the same time, the moisture carried by the return air is adsorbed by the adsorption material on the surface of the first heat exchanger 5, thereby cooling and dehumidifying the return air. The return air is then purified by the first filter 3 and then, driven by the first fan 21, reaches the first outdoor air outlet 11 and is discharged outdoors, completing the exhaust process.

[0148] There are two situations in the refrigerant circuit:

[0149] The first situation: when the humidification load is not large, the outdoor heat exchanger 10 does not work.

[0150] First solenoid valve 200 Reversing valve 8-0 Second solenoid valve 500 The third solenoid valve 400 Open (connected) ON Close (disconnect) Open (connected)

[0151] The reversing valve 8 - 0 is in the ON state, that is, the D pipe of the reversing valve 8 - 0 is connected to the E pipe, and the C pipe is connected to the S pipe. At this time, since the D pipe is not connected to the C pipe, the exhaust port of the compressor 7 is not connected to the outdoor heat exchanger 10.

[0152] Reference Figure 13 Refrigerant circuit: The high-temperature and high-pressure refrigerant is delivered from the exhaust port of the compressor 7, first passes through the first solenoid valve 200, and is then diverted to the three four-way valves 8 (at this time, it is in the OFF state, and the states may be inconsistent), and then flows to each humidity control indoor unit (the flow rate of each humidity control indoor unit is determined by 9-1, 9-2, and 9-3). The refrigerant reaches the second heat exchanger 6 of each humidity control indoor unit, transfers heat to the fresh air, and the refrigerant becomes a low-temperature and high-pressure two-phase refrigerant, and then flows to the electronic expansion valve 9, is throttled and reduced in pressure to become a low-temperature and low-pressure liquid refrigerant, and then flows to the first heat exchanger 5 of each humidity control indoor unit, absorbs the heat of the air outside the pipe and becomes a low-temperature and low-pressure gaseous refrigerant, and then flows to the E pipe of the four-way valve 8, and then from the S pipe of the four-way valve 8 through the third solenoid valve 400, back to the compressor 7, thus completing a refrigerant cycle.

[0153] The second situation: when the humidification load is large, the outdoor heat exchanger 10 is in operation.

[0154] First solenoid valve 200 Reversing valve 8-0 Second solenoid valve 500 The third solenoid valve 400 Open (connected) ON Open (connected) Close (disconnect)

[0155] The reversing valve 8-0 is in the ON state, that is, the D pipe of the reversing valve 8-0 is connected to the E pipe, and the C pipe is connected to the S pipe. At this time, since the D pipe is not connected to the C pipe, the exhaust port of the compressor 7 is not connected to the outdoor heat exchanger 10, and the outdoor heat exchanger 10 is connected to the intake port of the compressor 7.

[0156] Reference Figure 14Refrigerant circuit: The high-temperature, high-pressure refrigerant is delivered from the exhaust port of the compressor 7, passes through the first solenoid valve 200, and is then divided into three four-way valves 8 (at this time, they are in the ON state, but the states can also be inconsistent). Then, it flows to each humidity control unit (the flow rate of each humidity control unit is determined by 9-1, 9-2, and 9-3). The refrigerant reaches the second heat exchanger 6 of each humidity control unit, transfers heat to the fresh air, and the refrigerant becomes a low-temperature, high-pressure two-phase refrigerant. It then flows to the electronic expansion valve 9, is throttled and reduced in pressure to become a low-temperature, low-pressure liquid refrigerant, and then flows to the first heat exchanger 5 of each humidity control unit, absorbs heat from the air outside the pipe, and becomes a low-temperature, low-pressure gaseous refrigerant. It then flows to the E pipe of the four-way valve 8, and then from the S pipe of the four-way valve 8 to the outdoor heat exchanger 10 through the second solenoid valve 500, where it continues to absorb heat from the air outside the pipe. Then, it returns to the compressor 7 through the reversing valve 8-0, thus completing one refrigerant cycle.

[0157] In this way, the humidification process continuously cycles between the first state and the second state.

[0158] In the second case, the outdoor heat exchanger 10 is used as an evaporator, which can improve the heating capacity of the system, so that the system can meet the heating and humidification needs when the outdoor temperature is low, avoiding the problem of low regeneration temperature and poor humidification performance of the system when the outdoor temperature is extremely low in winter.

[0159] <Compressor frequency calculation>

[0160] In some embodiments of the present application, the fresh air humidity control multi-split system further includes: a temperature and humidity sensor for detecting the outdoor fresh air temperature Toa and humidity Hoa.

[0161] The controller calculates the absolute humidity doa of the outdoor fresh air based on Toa and Hoa detected by the temperature and humidity sensor, and controls the frequency F×1 of the compressor based on doa and the set absolute humidity ds indoors.

[0162] Specifically, in dehumidification mode, the frequency of the compressor is calculated according to the following formula:

[0163]

[0164] Among them, A, B, and n are constants;

[0165] Q represents the set air volume, M represents the maximum air volume, or Q represents the number of humidity control units turned on, M represents the total number of humidity control units;

[0166] The C value is the corrected value:

[0167] Judgment conditions C value 0≤doa-ds≤2 -5 2<doa-ds≤4 0 4<doa-ds≤8 3 8<doa-ds≤12 6 12<doa-ds 10

[0168] In humidification mode, the frequency of the compressor is calculated according to the following formula:

[0169]

[0170] Among them, A1, B1, and n1 are constants;

[0171] Q represents the set air volume, M represents the maximum air volume, or Q represents the number of humidity control indoor units that are turned on, and M represents the total number of humidity control indoor units.

[0172] The C1 value is the corrected value:

[0173] Judgment conditions C1 value 0≤ds-doa≤2 -5 2<ds-doa≤4 0 4<ds-doa≤8 5 8<ds-doa 10

[0174] The above compressor frequency formula is fitted by the dehumidification capacity under different working conditions, and then revised based on multiple test results, so that the operation of the compressor is more stable and reliable while meeting different dehumidification requirements without causing energy waste.

[0175] The number of indoor units (or air volume parameters) Q and M are introduced into the formula. When the number of turned-on indoor units decreases (or the air volume decreases), the compressor can automatically reduce its frequency.

[0176] In addition, the fresh air temperature Toa is introduced into the formula in the humidification mode. When Toa≤0℃, the frequency of the compressor can be reduced, thereby preventing the evaporation temperature from being too low and causing frost. If frost forms, it may cause the adsorption material on the surface of the heat exchanger to crack.

[0177] In some embodiments of the present application, the following opening and closing controls are provided for various valves in the refrigerant circuit:

[0178] The operating mode of the unit is determined according to the difference between doa and ds: if doa-ds≥0, it enters the dehumidification mode; otherwise, it enters the humidification mode.

[0179] After entering the dehumidification mode, determine whether Pd≥α or doa-ds≥X1 is established; if established, control the first solenoid valve to be disconnected, the reversing valve to be in the ON state (D tube and C tube are connected), the second solenoid valve to be disconnected, and the third solenoid valve to be connected; if not established, control the first solenoid valve to be connected, the reversing valve to be in the OFF state (D tube and E tube are connected), the second solenoid valve to be disconnected, and the third solenoid valve to be connected.

[0180] Wherein, Pd represents the exhaust pressure of the compressor; α and X1 are preset values, for example, X1 = 12 g / kgDA.

[0181] If the above conditions are met, the state of each valve is controlled so that the refrigerant circuit operates according to the second situation, and the outdoor heat exchanger 10 is involved in the system; if the above conditions are not met, the state of each valve is controlled so that the refrigerant circuit operates according to the first situation, and the outdoor heat exchanger 10 is not involved in the system.

[0182] Pd≥α or doa-ds≥12g / kgDA indicates that the humidity of the outdoor fresh air is relatively high or the cooling capacity is insufficient. Under this condition, the outdoor heat exchanger is involved in the system to increase the cooling and dehumidification capacity of the system.

[0183] The exhaust pressure Pd can be calculated based on the temperature detection value of the gas pipe temperature sensor in the refrigerant circuit, which is applicable to the existing technology and will not be described in detail here.

[0184] After entering the humidification mode, determine whether Ps<β or doa-ds≤X2 is established; if established, control the first solenoid valve to be connected, the reversing valve is in the ON state (D tube and E tube are connected), the second solenoid valve is connected, and the third solenoid valve is disconnected; if not established, control the first solenoid valve to be connected, the reversing valve is in the ON state (D tube and E tube are connected), the second solenoid valve is disconnected, and the third solenoid valve is connected.

[0185] Wherein, Ps represents the exhaust pressure of the compressor; β and X2 are preset values, for example, X2 = -5g / kgDA.

[0186] If the above conditions are met, the state of each valve is controlled so that the refrigerant circuit operates according to the second situation, and the outdoor heat exchanger 10 is involved in the system; if the above conditions are not met, the state of each valve is controlled so that the refrigerant circuit operates according to the first situation, and the outdoor heat exchanger 10 is not involved in the system.

[0187] Ps<β or doa-ds≤-5g / kgDA indicates that the humidity of the outdoor fresh air is relatively low or the heating capacity is insufficient. Under this condition, the outdoor heat exchanger is involved in the system to increase the heating and regeneration capacity of the system.

[0188] In some embodiments of the present application, a method for controlling the frequency and switching time of a compressor according to latent heat load and sensible heat load is proposed.

[0189] Specifically, the present application also has an indoor temperature and humidity sensor for detecting the indoor return air temperature Tra and humidity Hra, and the controller can calculate the absolute humidity dra of the indoor return air based on the detection values Tra and Hra of the indoor temperature and humidity sensor;

[0190] Then calculate the sensible heat factor SHF according to the following formula;

[0191] Latent heat load Qq = E × [Gρ × (doa-dra)];

[0192] Sensible heat load Qx = Cm × [Gρ × (Toa-Tra)];

[0193] Sensible heat factor SHF = Qx / (Qx+Qq);

[0194] Among them, G is the air volume, ρ is the density, and E and Cm are constants.

[0195] If SHF≥0.7 is satisfied, the frequency of the compressor is controlled according to the following formula with the goal of controlling the evaporation temperature:

[0196] Fx1=A3×(SHF) 2 +TL / Te×(SHF);

[0197] Wherein, TL represents the gas pipe temperature detection value in the refrigerant circuit, Te represents the liquid pipe temperature detection value in the refrigerant circuit, and A3 is a constant.

[0198] When the calculated value of F×1 is higher than the maximum frequency limit value F×1max of the compressor (for example, F×1max=70 Hz), the process is executed according to FX1=Fx1max.

[0199] If SHF < 0.3, the commutation time is calculated according to the following formula:

[0200] TH=A2×(SHF) 2 +B2×(SHF);

[0201] Among them, A2 and B2 are constants.

[0202] The commutation time has a minimum preset value THmin, for example, THmin=3min; when the calculated value of TH is less than THmin, the commutation time is executed as TH=THmin.

[0203] When in a high temperature and high humidity or high temperature and low humidity environment, due to the large difference between the latent heat load and the sensible heat load, the unit can be controlled according to the sensible heat load and the latent heat load to achieve greater energy saving.

[0204] When the SHF is high, the unit operates in high sensible heat mode, controlling the compressor frequency based on the SHF. When the SHF is low, the dehumidification capacity can be maximized by shortening the switching time, without the need for compressor frequency control. Therefore, in high-temperature and high-humidity or high-temperature and low-humidity conditions, controlling the unit based on sensible and latent heat loads can achieve greater energy savings.

[0205] The first concept of the present application is to switch the fresh air duct and the return air duct by the forward and reverse rotation of the fan, without the need for an air valve switching device, which simplifies the product structure, reduces costs, and makes the product smaller, saving space.

[0206] The second concept of the present application is to switch the fresh air duct and the return air duct by the forward and reverse rotation of the fan, without the need for a damper switching device. The reduction in components reduces the internal resistance of the unit, improves the working efficiency of the unit, and reduces energy consumption.

[0207] The third concept of the present application is to switch the fresh air duct and the return air duct by the forward and reverse rotation of the fan, and to achieve humidification or dehumidification by coating adsorption material on the heat exchanger, making the product structure more compact.

[0208] The fourth concept of the present application is to form a multi-split system with multiple humidity-control indoor units, and respectively set up multiple four-way valves, sharing a compressor, thereby realizing independent control of each humidity-control indoor unit, eliminating the need for synchronization between the humidity-control indoor units, and being more flexible and intelligent.

[0209] The fifth concept of the present application is to establish a connection between the frequency of the compressor and the absolute humidity doa of the outdoor fresh air and the absolute humidity ds set as the indoor target, so that the operation of the compressor is more stable and reliable while meeting different dehumidification requirements and will not cause energy waste.

[0210] The sixth concept of the present application is to establish a relationship between the frequency formula of the compressor and the air volume, so that the compressor can automatically reduce the frequency when the air volume decreases.

[0211] The seventh concept of the present application is to introduce the Toa variable into the compressor frequency formula in the humidification mode. When Toa≤0℃, the frequency of the compressor automatically decreases, which can effectively prevent frosting caused by the evaporation temperature being too low, and avoid the risk of frosting causing cracking of the adsorption material on the surface of the heat exchanger.

[0212] The eighth concept of the present application is to add an outdoor heat exchanger in the refrigerant circuit. When the outdoor temperature is high and the humidity is high, the outdoor heat exchanger enters the system to increase the cooling capacity of the system; when the outdoor temperature is low, the outdoor heat exchanger enters the system to increase the heating capacity of the system, thereby avoiding the problem of reduced dehumidification performance of the system when the outdoor temperature is high or low regeneration temperature and poor humidification performance when the outdoor temperature is ultra-low.

[0213] The ninth concept of the present application is to control the compressor frequency or reversing time according to the sensible heat load and the sensible heat load, so as to achieve greater energy saving of the unit at high temperature and high humidity or high temperature and low humidity.

[0214] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present application, rather than to limit them. Although the present application has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some or all of the technical features therein. These modifications or replacements do not deviate the essence of the corresponding technical solutions from the scope of the technical solutions of the embodiments of the present application.

[0215] For ease of explanation, the above description has been presented in conjunction with specific embodiments. However, the above exemplary discussion is not intended to be exhaustive or to limit the embodiments to the specific forms disclosed above. Based on the above teachings, various modifications and variations are possible. The above embodiments have been selected and described to better explain the principles and practical applications, thereby enabling those skilled in the art to better utilize the embodiments and various different variations of the embodiments suitable for specific use considerations.

Claims

1. A fresh air humidity control multi-split unit, characterized in that: include: m sets of indoor humidity control units, m≥2; The humidity control indoor unit includes: The first air duct and the second air duct are connected to the indoor and outdoor respectively; a first fan and a second fan, wherein the first fan is disposed in the first air duct, and the second fan is disposed in the second air duct; A first heat exchanger and a second heat exchanger, both of which are coated with adsorption materials, the first heat exchanger is arranged in the first air duct, and the second heat exchanger is arranged in the second air duct; The humidity control unit can realize two state changes: In one state, the first fan is used as a supply fan, so that fresh air flows into the room through the first air duct; the second fan is used as an exhaust fan, so that return air flows into the room through the second air duct; When switching from one state to another, the first fan changes direction and acts as an exhaust fan, so that the return air flows to the outside through the first air duct; the second fan changes direction and acts as a supply fan, so that the fresh air flows to the room through the second air duct; Wherein, in each of the humidity control indoor units, the first heat exchanger and the second heat exchanger are connected in series to form a heat exchange branch; The fresh air humidity control multi-split system also includes: a compressor, a four-way valve and an outdoor heat exchanger; The two ends of the heat exchange branch are respectively connected to the C pipe and the E pipe of the four-way valve, and the air intake of the compressor is connected to the S pipe of the four-way valve; The fresh air humidity control multi-split system also includes: a first solenoid valve connected in parallel with the outdoor heat exchanger between the exhaust port of the compressor and the D pipe of the four-way valve; A reversing valve is connected between the compressor and the outdoor heat exchanger, wherein the D pipe of the reversing valve is connected to the exhaust port of the compressor, the C pipe of the reversing valve is connected to the outdoor heat exchanger, the S pipe of the reversing valve is connected to the intake port of the compressor, and the E pipe of the reversing valve is blocked; A one-way valve connected in series between the outdoor heat exchanger and the D pipe of the four-way valve; a second solenoid valve, one end of which is connected to the S-tube of the four-way valve, and the other end of which is connected between the outdoor heat exchanger and the one-way valve; a third solenoid valve connected in series between the S-tube of the four-way valve and the suction port of the compressor; Multiple temperature and humidity sensors for detecting outdoor temperature Toa and humidity Hoa, as well as indoor temperature Tra and humidity Hra; The controller is used to calculate the outdoor absolute humidity doa according to the outdoor temperature and humidity, calculate the indoor absolute humidity dra according to the indoor temperature and humidity, and calculate the latent heat load Qq, the sensible heat load Qx and the sensible heat factor SHF according to doa, dra, Toa and Tra; ; When SHF is less than 0.3, the switching time of the four-way valve is controlled ; Among them, A2 and B2 are constants.

2. The fresh air humidity control multi-split unit according to claim 1 is characterized in that: There are m four-way valves; the heat exchange branches are connected to the four-way valves in a one-to-one correspondence, and the m four-way valves are arranged in parallel.

3. The fresh air humidity control multi-split unit according to claim 1 is characterized in that: Also includes: Controller for: In the dehumidification mode, determine whether Pd≥α or doa-ds≥X1 is true; if so, the first solenoid valve is controlled to be disconnected, the D and C pipes of the reversing valve are connected, the second solenoid valve is disconnected, and the third solenoid valve is connected; if not, the first solenoid valve is controlled to be connected, the D and E pipes of the reversing valve are connected, the second solenoid valve is disconnected, and the third solenoid valve is connected; Wherein, Pd represents the exhaust pressure of the compressor, doa represents the outdoor absolute humidity, ds represents the set indoor absolute humidity; α and X1 are preset values.

4. The fresh air humidity control multi-split unit according to claim 1, characterized in that: Also includes: Controller for: In the humidification mode, determine whether Ps < β or doa-ds ≤ X2; if so, control the first solenoid valve to be connected, the D and E pipes of the reversing valve to be connected, the second solenoid valve to be connected, and the third solenoid valve to be disconnected; if not, control the first solenoid valve to be connected, the D and E pipes of the reversing valve to be connected, the second solenoid valve to be disconnected, and the third solenoid valve to be connected; Wherein, Ps represents the exhaust pressure of the compressor, doa represents the outdoor absolute humidity, ds represents the set indoor absolute humidity; β and X2 are preset values.

5. The fresh air humidity control multi-split unit according to claim 1 is characterized in that: Also includes: Temperature and humidity sensor, used to detect the temperature Toa and humidity Hoa of outdoor fresh air; The controller is used to calculate the absolute humidity doa of the outdoor fresh air based on Toa and Hoa, and control the frequency Fx1 of the compressor based on the difference between doa and the set indoor absolute humidity ds; In dehumidification mode, ； Among them, A, B, and n are constants; C is the correction value; Q is the number of humidity control units that are turned on, and M is the total number of humidity control units.

6. The fresh air humidity control multi-split unit according to claim 1, characterized in that: Also includes: Temperature and humidity sensor, used to detect the temperature Toa and humidity Hoa of outdoor fresh air; The controller is used to calculate the absolute humidity doa of the outdoor fresh air based on Toa and Hoa, and control the frequency Fx1 of the compressor based on the difference between doa and the set indoor absolute humidity ds; In humidification mode, ； Among them, Toa represents the temperature of outdoor fresh air; A1, B1, n1 are constants; C1 is the correction value; Q is the number of humidity control units that are turned on, and M is the total number of humidity control units.

7. The fresh air humidity control multi-split unit according to claim 1, characterized in that: When SHF≥0.7, control the compressor frequency ; Wherein, TL represents the gas pipe temperature detection value in the refrigerant circuit, Te represents the liquid pipe temperature detection value in the refrigerant circuit, and A3 is a constant.

8. The fresh air humidity control multi-split unit according to claim 1, characterized in that: The latent heat load Qq, sensible heat load Qx and sensible heat factor SHF are calculated according to the following formulas: ； ； Among them, G is the air volume, ρ is the density, and E and Cm are constants.

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