Air conditioning and its control methods

Abstract

This application discloses an air conditioner and its control method, belonging to the field of air handling technology. The air conditioner includes: an outdoor unit; the outdoor unit includes: a first air duct; an outdoor heat exchanger disposed within the first air duct; an outdoor fan for driving outdoor airflow within the first air duct; a compressor; a second air duct is also provided within the casing, the second air duct being connected to a fresh air duct for supplying fresh air into the room; the outdoor unit further includes: a rotor having a first portion located in the first air duct and a second portion located in the second air duct, the first portion being located on the windward side of the outdoor heat exchanger when the outdoor fan rotates in a first direction; a controller for determining whether enhanced operation is needed based on the detection values ​​of a fresh air humidity detection device and an indoor humidity detection device, and controlling the compressor to increase its frequency or controlling the outdoor fan to increase its speed when enhanced operation is determined to be needed. This air conditioner can achieve fresh air humidification / dehumidification while avoiding frost formation on the outdoor heat exchanger.

Description

Technical Field

[0001] This application relates to the field of air handling technology, and more particularly to an air conditioner and its control method. Background Technology

[0002] An air conditioner is a device that uses a refrigeration cycle to control the temperature and humidity suitable for human activities. In winter, when the air conditioner is in heating mode, the outdoor heat exchanger acts as an evaporator. When the evaporation temperature is below 0°C, its surface is prone to frost formation.

[0003] The common defrosting method in the existing technology is to defrost by reversing the refrigeration system.

[0004] This defrosting method has a long preparation time, absorbs heat from the room during defrosting, and the air temperature rises slowly after defrosting, causing severe fluctuations in indoor temperature and affecting user comfort. Summary of the Invention

[0005] This application provides an air conditioner and its control method, which uses an adsorption wheel to dehumidify outdoor air before it passes through an outdoor heat exchanger, thus avoiding frost formation on the outdoor heat exchanger.

[0006] In one aspect of this application, an air conditioner includes: an outdoor unit; the outdoor unit includes: a housing having a first air duct inside, the two ends of the first air duct being connected to the outside; an outdoor heat exchanger disposed within the first air duct for exchanging heat with outdoor air within the first air duct; an outdoor fan for driving the flow of outdoor air within the first air duct; and a compressor for compressing refrigerant; wherein the housing also includes a second air duct connected to a fresh air duct for supplying fresh air into the room; the outdoor unit further includes: a rotor rotatably connected within the housing, the rotor having a first portion located in the first air duct and a second portion located in the second air duct, the first portion being located on the windward side of the outdoor heat exchanger when the outdoor fan rotates in a first direction; the air conditioner further includes: a fresh air humidity detection device for detecting the supply humidity of the fresh air; an indoor humidity detection device for detecting the humidity of the indoor environment; and a controller for: determining whether enhanced operation is required based on the detection values ​​of the fresh air humidity detection device and the indoor humidity detection device, and controlling the compressor to increase its frequency or controlling the outdoor fan to increase its speed when it is determined that enhanced operation is required.

[0007] In some embodiments, the controller is configured to: in cooling mode, when the compressor has increased its frequency to the upper limit of the operating frequency and still needs to be operated more strongly, or when the speed of the outdoor fan has increased to the upper limit of the fan speed and still needs to be operated more strongly, control the outdoor fan to rotate in a second direction opposite to the first direction, so that the outdoor air is first heated by the outdoor heat exchanger and then flows to the impeller, thereby removing the moisture absorbed by the impeller.

[0008] In some embodiments, the controller is configured to: when the indoor relative humidity is not greater than a preset lower limit of relative humidity or no enhanced operation is required during the rotation of the outdoor fan in the second direction, control the outdoor fan to return to the first direction.

[0009] In some embodiments, it further includes: a fresh air fan for driving fresh air flow into the room;

[0010] The controller is used to: in heating mode, when the compressor has increased its frequency to the upper limit of the operating frequency and still needs to be operated more strongly, or when the outdoor fan speed has increased to the upper limit of the fan speed and still needs to be operated more strongly, control the fresh air fan to reduce its speed.

[0011] In some embodiments, in the step of controlling the fresh air fan to reduce its speed, the fresh air fan reduces its speed, and after a preset time t3, it returns to determine whether it is necessary to strengthen the operation. If not, it controls the fresh air fan to maintain the current speed; if so, it controls the fresh air fan to continue to reduce its speed.

[0012] In some embodiments, the controller is configured to: in cooling mode, determine whether dsa≤din-APr / G is true; if true, it is determined that no enhanced operation is needed and the air conditioner maintains its current state; if false, it is determined that enhanced operation is needed; in heating mode, determine whether dsa≥din-BPr / G is true; if true, it is determined that no enhanced operation is needed and the air conditioner maintains its current state; if false, it is determined that enhanced operation is needed; where dsa represents the moisture content of fresh air, din represents the moisture content of indoor air, Pr represents the moisture dissipation from indoor occupants, G represents the fresh air supply volume, and A and B are correction coefficients.

[0013] In some embodiments, the controller is configured to: when enhanced operation is required, in cooling mode, determine whether the compressor's discharge pressure is not less than a first preset critical value; if not, control the compressor to increase its frequency; if so, control the outdoor fan to increase its speed; in heating mode, determine whether the compressor's discharge pressure is not greater than a second preset critical value; if so, control the compressor to increase its frequency; if not, control the outdoor fan to increase its speed.

[0014] In some embodiments, in the step of controlling the compressor frequency increase, the compressor frequency is increased, and after a preset time t1, it is determined whether the operation needs to be strengthened. If so, the compressor frequency is controlled to continue to increase until it reaches the upper limit of the operating frequency; if not, the compressor frequency is kept unchanged.

[0015] In some embodiments, in the step of controlling the outdoor fan to increase its speed, the outdoor fan is controlled to increase its speed, and after a preset time t2, it is determined whether the operation needs to be strengthened. If so, the outdoor fan is controlled to increase its speed again until the upper limit of the wind speed is reached; if not, the speed of the outdoor fan is kept unchanged.

[0016] In another aspect of this application, an air conditioning control method is provided. The air conditioner includes an outdoor unit. The outdoor unit includes: a housing with a first air duct inside, the two ends of which are respectively connected to the outside; an outdoor heat exchanger disposed in the first air duct for exchanging heat with the outdoor air in the first air duct; an outdoor fan for driving the outdoor air in the first air duct to flow; and a compressor for compressing refrigerant. The housing also includes a second air duct connected to a fresh air duct for supplying fresh air into the room. The outdoor unit further includes: a rotor rotatably connected to the housing, the rotor having a first portion located in the first air duct and a second portion located in the second air duct, the first portion being located on the windward side of the outdoor heat exchanger when the outdoor fan rotates in a first direction. The control method includes: detecting the supply humidity of the fresh air and the humidity of the indoor environment; determining whether enhanced operation is needed based on the supply humidity of the fresh air and the humidity of the indoor environment, and controlling the compressor to increase its frequency or controlling the outdoor fan to increase its speed when enhanced operation is determined to be needed. Attached Figure Description

[0017] Figure 1 A schematic diagram of an air conditioner according to some embodiments is shown;

[0018] Figure 2 An interior top view of the outdoor unit of an air conditioner according to some embodiments is shown;

[0019] Figure 3 An interior top view of the outdoor unit of an air conditioner according to some other embodiments is shown;

[0020] Figure 4 An exploded view of the outdoor unit of an air conditioner according to some embodiments is shown;

[0021] Figure 5 A schematic diagram of the refrigerant circuit for an air conditioner that does not dehumidify fresh air in cooling mode, according to some embodiments, is shown.

[0022] Figure 6 A schematic diagram of the refrigerant circuit for fresh air dehumidification in air conditioning in cooling mode is shown according to some embodiments;

[0023] Figure 7 A schematic diagram of the refrigerant circuit for an air conditioner in heating mode without humidifying the fresh air is shown according to some embodiments.

[0024] Figure 8A schematic diagram of the refrigerant circuit for fresh air humidification in an air conditioner in heating mode, according to some embodiments, is shown.

[0025] Figure 9 A block diagram illustrating the control signal flow of an air conditioner according to some embodiments is shown;

[0026] Figure 10 A control flowchart for fresh air dehumidification of an air conditioner according to some embodiments is shown;

[0027] Figure 11 A control flowchart for fresh air humidification of an air conditioner according to some embodiments is shown;

[0028] Figure 12 A control flowchart for preventing frost formation in an air conditioner according to some embodiments is shown;

[0029] Figure 13 A control flowchart for indoor humidification of an air conditioner according to some embodiments is shown;

[0030] Figure 14 An optimized control flowchart for indoor humidification of an air conditioner according to some embodiments is shown. Detailed Implementation

[0031] To make the objectives and implementation methods of this application clearer, the exemplary implementation methods of this application will be clearly and completely described below with reference to the accompanying drawings of the exemplary embodiments of this application. Obviously, the exemplary embodiments described are only some embodiments of this application, and not all embodiments.

[0032] The embodiments of this application will now be described in detail, with examples of the embodiments shown in the accompanying drawings.

[0033] Reference Figure 1 The air conditioner according to the embodiments of this application includes: an outdoor unit 100 located in an outdoor space for performing heat exchange between a refrigerant and outdoor air; and an indoor unit 200 located in an indoor space for performing heat exchange between a refrigerant and indoor air.

[0034] The indoor unit 200 includes an indoor unit body 210; an indoor unit intake 211, located on the top surface of the indoor unit body 210, for collecting indoor air to enter the indoor unit body 210; and an indoor unit exhaust 212, located at the lower front of the indoor unit body 210, for discharging heat-exchanged air. The above illustration uses a wall-mounted structure as an example. In other embodiments, such as a floor-standing cabinet structure, the indoor unit intake 211 is located at the rear of the indoor unit body 210, and the indoor unit exhaust 212 is located at the front of the indoor unit body 210.

[0035] Reference Figures 2 to 4 The outdoor unit 100 includes a housing 1, which forms the overall appearance of the outdoor unit 100.

[0036] The housing 1 is divided into a fan chamber 11 and a compressor chamber 12 by a partition plate 10. Normally, the fan chamber 11 and the compressor chamber 12 are arranged horizontally.

[0037] The outdoor heat exchanger 112 and outdoor fan 3 in the outdoor unit 100 are installed in the fan chamber 11, and the compressor 111, outdoor expansion valve 114 and other components of the outdoor unit 100 are installed in the compressor chamber 12.

[0038] An outdoor inlet 13 and an outdoor outlet 14 are respectively provided on a set of opposite side walls of the casing 1. The outdoor inlet 13 connects to the ventilation chamber 11 and the outdoor atmosphere, and the outdoor outlet 14 connects to the ventilation chamber 11 and the outdoor atmosphere.

[0039] The fan cavity 11 includes a first air duct 15 and a second air duct 16.

[0040] The first air duct 15 is connected to an outdoor inlet 13 and an outdoor outlet 14 at its two ends, respectively. An outdoor heat exchanger 112 and an outdoor fan 3 are both installed within the first air duct 15. The outdoor fan 3 circulates outdoor air between the first air duct 15 and the outdoor atmosphere, while the outdoor heat exchanger 112 exchanges heat with the outdoor air within the first air duct 15. Outdoor air enters the first air duct 15 from the outdoor inlet 13, exchanges heat with the outdoor heat exchanger 112, and is then blown outdoors from the outdoor outlet 14.

[0041] One end of the second air duct 16 is connected to the outdoor entrance 13, and the other end of the second air duct 16 is the fresh air outlet 512. The fresh air outlet 512 is connected to the fresh air duct 400, which extends into the room, thus connecting the second air duct 16 with the room.

[0042] The air conditioner may include a fresh air fan 52 for driving airflow within the second air duct 16 into the room. For ease of description, the air within the first air duct 15 is also referred to as outdoor air, and the air within the second air duct 16 is also referred to as fresh air.

[0043] The fresh air fan 52 can be installed in the second air duct 16, so that fresh air from the outdoor atmosphere enters the second air duct 16 from the outdoor inlet 13 and then enters the room along the fresh air duct 400.

[0044] The indoor end of the 400 fresh air duct can directly supply fresh air into the room; or, combined with... Figure 1 The indoor end of the fresh air duct 400 can also be connected to the indoor unit 200, and then fresh air is supplied to the room through the fresh air outlet 213 on the indoor unit 200.

[0045] In an embodiment where the fresh air duct 400 supplies air through the indoor unit 200, the fresh air fan 52 may also be installed inside the indoor unit 200.

[0046] Continue to refer to Figure 2 and Figure 3 The outdoor unit 100 also includes a desiccant 6 for dehumidification. The desiccant 6 is made of a moisture-absorbing material and includes an adsorption zone and a regeneration zone, one of which is located in a first air duct 15 and the other is located in a second air duct 16.

[0047] When the temperature of the air passing through rotor 6 is relatively low, this part of rotor 6 is the adsorption zone, which can adsorb moisture in the air; when the temperature of the air passing through rotor 6 is relatively high, this part of rotor 6 is the regeneration zone, where the high temperature air causes the moisture in the regeneration zone to be removed, and the adsorbent in the regeneration zone is regenerated.

[0048] The rotor 6 is rotatably connected inside the housing 1 and is located on the windward side of the outdoor heat exchanger 112. As the rotor 6 rotates, each part of the rotor 6 continuously changes between the adsorption zone and the regeneration zone.

[0049] Understandably, when the outdoor air temperature in the first air duct 15 is relatively high and the fresh air temperature in the second air duct 16 is relatively low, the part of the rotor 6 located in the first air duct 15 is the regeneration zone and the part located in the second air duct 16 is the adsorption zone; when the outdoor air temperature in the first air duct 15 is relatively low and the fresh air temperature in the second air duct 16 is relatively high, the part of the rotor 6 located in the first air duct 15 is the adsorption zone and the part located in the second air duct 16 is the regeneration zone.

[0050] Reference Figure 4 Since the adsorption zone and regeneration zone change according to the air temperature in the air duct, for ease of description, the part of the rotor 6 located in the first air duct 15 is called the first part 61, and the part of the rotor 6 located in the second air duct 16 is called the second part 62.

[0051] The area of ​​the second part 62 of the rotating wheel 6 is smaller than the area of ​​the first part 61. Specifically, the area of ​​the second part 62 can be set to be no more than 1 / 3 of the area of ​​the first part 61.

[0052] For example, the area of ​​the second part 62 occupies one-quarter of the rotor 6. In this way, the first partition 17 is at a right angle near the axis of the rotor 6, which can make the shape of the second air duct 16 more regular, thereby making the shape of the fresh air heat exchanger 71 adapted to the second air duct 16 more regular and reducing the manufacturing difficulty.

[0053] The outdoor heat exchanger 112 has a larger area to ensure the heat exchange capacity on the outdoor side. Therefore, the first air duct 15 has a larger area than the second air duct 16.

[0054] Reference Figure 2 and Figure 3 The outdoor unit 100 also includes a heating device 7, which is located in the second air duct 16 and on the windward side of the rotor 6. The heating device 7 is used to heat the fresh air in the second air duct 16, thereby raising the temperature of the fresh air and causing the moisture in the regeneration zone of the rotor 6 to be removed.

[0055] The heating device 7 can be a fresh air heat exchanger, an electric heating device, or a combination of both. Specifically, in one embodiment, the windward side of the rotor 6 is provided only with a fresh air heat exchanger 71, which functions as a condenser during air conditioning heating operation; in another embodiment, the windward side of the rotor 6 is provided only with an electric heating device 72, such as an electric heating wire, which operates by energizing the electric heating device 72; in yet another embodiment, the windward side of the rotor 6 is provided with both a fresh air heat exchanger 71 and an electric heating device 72, wherein the electric heating device 72 is located between the fresh air heat exchanger 71 and the rotor 6.

[0056] When the air conditioner is in heating mode in winter, the outdoor heat exchanger 112 is used as an evaporator. The surface of the evaporator is prone to frost, which will affect the heating capacity of the air conditioner.

[0057] This application installs a rotor 6 on the windward side of the outdoor heat exchanger 112, so that the outdoor air is first absorbed by the rotor 6 before flowing to the outdoor heat exchanger 112, ensuring that the air flowing to the outdoor heat exchanger 112 is dry and low-temperature air, thus avoiding the problem of frost forming on the outdoor heat exchanger 112 in winter.

[0058] In other embodiments, the outlet end of the second air duct 16 may not be connected to the fresh air duct 400. The outlet end of the second air duct 16 is also connected to the outside. Outdoor air enters the second air duct 16 from the outdoor inlet 13, passes through the heating device 7 and the rotor 6, and then circulates to the outside.

[0059] According to an embodiment of this application, in the first air duct 15, the outdoor heat exchanger 112 may be located between the rotor 6 and the outdoor fan 3, or the outdoor fan 3 may be located between the rotor 6 and the outdoor heat exchanger 112.

[0060] Reference Figure 2 The first partition 17 extends from the windward side edge of the second part of the rotor 6 to the outdoor inlet 13, and the second partition 18 extends from the air outlet side edge of the second part of the rotor 6 away from the rotor 6 to the side wall where the outdoor outlet 14 is located. In this way, the first partition 17, the second partition 18, the top wall of the housing 1, and the partition plate 10 form a second air duct 16.

[0061] The fresh air outlet 512 is located on the top wall of the housing 1; the fan cavity 11, excluding the second air duct 16, forms the first air duct 15.

[0062] In some embodiments of this application, reference is made to Figure 3 The outdoor unit 100 includes a fresh air module 5, which includes a fresh air housing 51 and a fresh air fan 52. The fresh air fan 52 is installed inside the fresh air housing 51.

[0063] The fresh air housing 51 is provided with a fresh air inlet 511 and a fresh air outlet 512. The fresh air inlet 511 faces the rotating wheel 6, and the fresh air outlet 512 faces upward. Since the structure of the fresh air module 5 is applicable to existing technology, it will not be described in detail here.

[0064] The fresh air module 5 can be set at the upper part of the fan cavity 11 so that the fresh air outlet 512 can be exposed from the top of the housing 1; the fresh air module 5 is also close to the partition plate 10, so that the second air duct 16 can be closer to the compressor cavity 12, thereby reducing the connection length of the refrigerant pipe between the fresh air heat exchanger 71 and the compressor 111.

[0065] The first partition 17 extends from the windward edge of the second part of the rotating wheel 6 to the outdoor inlet 13, and the second partition 18 extends from the air outlet edge of the second part of the rotating wheel 6 to the fresh air inlet of the fresh air module 5. In this way, the first partition 17, the second partition 18, the top wall of the housing 1, and the partition plate 10 form a second air duct 16.

[0066] In some embodiments, the outdoor entrance 13 may be configured as two separate entrances, one connected to the first air duct 15 as the entrance for outdoor air, and the other connected to the second air duct 16 as the entrance for fresh air.

[0067] Reference Figures 5 to 8 In the refrigerant circuit of the air conditioner, the compressor 111 compresses the refrigerant; the outdoor heat exchanger 112 performs heat exchange between the outdoor air and the refrigerant; the four-way valve 113 selectively guides the refrigerant compressed by the compressor 111 to the outdoor heat exchanger 112 or the indoor unit 200 according to the heating mode or cooling mode; the outdoor expansion valve 114 reduces the pressure of the refrigerant guided to or flowing out of the outdoor heat exchanger 112.

[0068] Compressor 111 receives external electrical energy to compress low-pressure gaseous refrigerant to high pressure.

[0069] In cooling mode, the four-way valve 113 guides the refrigerant compressed in the compressor 111 to the outdoor heat exchanger 112, and in heating mode, it guides the refrigerant compressed in the compressor 111 to the indoor unit 200.

[0070] The outdoor heat exchanger 112 condenses the refrigerant compressed by the compressor 111 in cooling mode and evaporates the refrigerant depressurized by the indoor unit 200 in heating mode.

[0071] In addition, a first shut-off valve 1151 and a second shut-off valve 1152 are respectively installed on the gas pipe and liquid pipe between the outdoor unit 100 and the indoor unit 200. The first shut-off valve 1151 is located between the outdoor heat exchanger 112 and the indoor unit 200, and the second shut-off valve 1152 is located between the four-way valve 113 and the indoor unit 200.

[0072] Specifically, the output end of the compressor 111 is connected to the D tube of the four-way valve 113, the C tube of the four-way valve 113 is connected to one end of the outdoor heat exchanger 112, the other end of the outdoor heat exchanger 112 is connected to one end of the indoor unit 200 after being connected in series with the first shut-off valve 1151, the E tube of the four-way valve 113 is connected to the other end of the indoor unit 200 after being connected in series with the second shut-off valve 1152, and the S tube of the four-way valve 113 is connected to the input end of the compressor 111.

[0073] In some embodiments of this application, the output end of the compressor 111 is connected in series with the first solenoid valve 1161 and then connected to the D tube of the four-way valve 113, and the E tube of the four-way valve 113 is connected in series with the second solenoid valve 1162 and then connected to the second shut-off valve 1152.

[0074] The outdoor unit 100 also includes a switching valve 117, which is also a four-way valve with four ports.

[0075] The output end of the compressor 111 is connected to the first port of the switching valve 117, the second port of the switching valve 117 is connected to the input end of the fresh air heat exchanger 71, the third port of the switching valve 117 is connected between the second solenoid valve 1162 and the second shut-off valve 1152, and the fourth port of the switching valve 117 is blocked.

[0076] The output of the fresh air heat exchanger 71 branches into two lines. The first line connects to the D-tube of the four-way valve 113, and the second line connects to the input of the compressor 111. A third solenoid valve 1163 is connected in series on the first line, and a fourth solenoid valve 1164 is connected in series on the second line.

[0077] In other embodiments, a three-way valve can replace the switching valve 117 described above. One port of the three-way valve is connected to the input end of the fresh air heat exchanger 71, the second port of the three-way valve is connected to the output end of the compressor 111, and the third port of the three-way valve is connected between the second solenoid valve 1162 and the second shut-off valve 1152.

[0078] The following describes the operating modes of air conditioners in conjunction with the refrigerant circuit:

[0079] Cooling mode

[0080] Operating status 1: Fresh air function is not turned on, fresh air fan 52 and rotor 6 are not working.

[0081] The status of each valve in the refrigerant circuit under this condition is shown in Table 1.

[0082] Table 1

[0083]

[0084] When the four-way valve 113 is in the OFF position: pipe D is connected to pipe C, and pipe E is connected to pipe S;

[0085] Switching valve 117 is in the ON state: the first interface is connected to the second interface, and the third interface is connected to the fourth interface.

[0086] Refrigerant circuit: Reference Figure 5 The arrows in the diagram indicate the refrigerant flow. The high-temperature, high-pressure refrigerant is discharged from the compressor 111 through the exhaust pipe, passes through the first solenoid valve 1161, reaches the four-way valve 113, and then reaches the outdoor heat exchanger 112 (which acts as a condenser) to exchange heat with the outdoor air. The refrigerant becomes a low-temperature, high-pressure liquid or gas-liquid two-phase refrigerant. Then, it passes through the outdoor expansion valve 114 to reduce its pressure and become a low-temperature, low-pressure liquid refrigerant. Then, it flows through the first shut-off valve 1151 to the indoor unit 200, where it exchanges heat with the indoor air and becomes a low-temperature, low-pressure gaseous refrigerant. Then, it returns to the outdoor unit 100 through the second shut-off valve 1152, and returns to the compressor's suction port through the second solenoid valve 1162 and the four-way valve 113, completing one refrigeration cycle.

[0087] First air duct: Reference Figure 2 The arrow above indicates the direction of outdoor air flow. Driven by the outdoor fan 3, the outdoor air first passes through the rotor 6 (which is not working), and then through the outdoor heat exchanger 112. At this time, the outdoor heat exchanger 112 acts as a condenser to dissipate heat to the outdoor air, and finally is discharged to the outside through the outdoor outlet 14, completing one heat dissipation process of the outdoor heat exchanger 112.

[0088] Operating status 2: Fresh air is on and dehumidification is not required; the fresh air fan is working, but the dehumidifier is not working.

[0089] The refrigerant circuit and the air flow in the first air duct are the same as in working state 1 under cooling mode. The difference is that there is ventilation in the second air duct.

[0090] Second air duct: Refer to Figure 2 The arrow below indicates the direction of fresh air flow. Driven by the fresh air fan 52, the fresh air first passes through the fresh air heat exchanger 71 (not working), then through the rotor 6 (not working), and then reaches the fresh air duct 400 from the fresh air outlet 512 and is sent into the room, completing one fresh air delivery process.

[0091] Operating status 3: Fresh air is turned on and dehumidification is required. The fresh air fan is working and the dehumidifier is working.

[0092] The status of each valve in the refrigerant circuit under this condition is shown in Table 2.

[0093] Table 2

[0094]

[0095] When the four-way valve 113 is in the OFF position: pipe D is connected to pipe C, and pipe E is connected to pipe S;

[0096] Switching valve 117 is in the OFF state: the first port is connected to the fourth port, and the third port is connected to the second port.

[0097] Refrigerant circuit: Reference Figure 6 The arrows indicate the refrigerant flow direction. High-temperature, high-pressure refrigerant is discharged from the compressor 111 through the exhaust pipe, passes through the first solenoid valve 1161, reaches the four-way valve 113, and then reaches the outdoor heat exchanger 112 (acting as a condenser) to exchange heat with the outdoor air. The refrigerant becomes a low-temperature, high-pressure liquid or gas-liquid two-phase refrigerant. Then, it passes through the outdoor expansion valve 114 to reduce its pressure and become a low-temperature, low-pressure liquid refrigerant. Then, it flows through the first shut-off valve 1151 to the indoor unit 200, where it exchanges heat with the indoor air and becomes a low-temperature, low-pressure gaseous refrigerant. Then, it returns to the outdoor unit 100 through the second shut-off valve 1152, and then flows to the switching valve 117. After passing through the switching valve 117, it flows to the fresh air heat exchanger 71 (acting as an evaporator) to exchange heat with the fresh air. Finally, it returns to the compressor's suction port through the fourth solenoid valve 1164, completing one refrigeration cycle.

[0098] First air duct: Reference Figure 2 As indicated by the arrow above, the outdoor air, driven by the outdoor fan 3, first passes through the regeneration zone of the rotor 6 to regenerate the moisture inside the rotor 6, and then passes through the outdoor heat exchanger 112. At this time, the outdoor heat exchanger 112 acts as a condenser to dissipate heat to the outdoor air, and finally is discharged to the outside through the outdoor outlet 14, completing one heat dissipation process of the outdoor heat exchanger 112.

[0099] Second air duct: Refer to Figure 2 The arrow below indicates that, driven by the fresh air fan 52, the fresh air first passes through the fresh air heat exchanger 71 (evaporator) to cool down and become a low-temperature, high-humidity state. When it passes through the adsorption zone of the rotor 6, the moisture it carries is adsorbed inside the rotor. Then, it reaches the fresh air duct 400 through the fresh air outlet 512 and is sent into the room, completing a fresh air cooling, dehumidification and transportation process.

[0100] When the air conditioner of this application introduces fresh air in cooling mode, it can achieve cooling and dehumidification of the fresh air.

[0101] Heating mode

[0102] Operating status 1: Fresh air is not turned on, and fresh air fan 52 and rotor 6 are not working.

[0103] The status of each valve in the refrigerant circuit under this condition is shown in Table 3.

[0104] Table 3

[0105]

[0106] Refrigerant circuit: Reference Figure 7 The arrows in the diagram indicate the refrigerant flow. The high-temperature, high-pressure refrigerant is discharged from the compressor 111 through the exhaust pipe, passes through the first solenoid valve 1161, reaches the four-way valve 113, and then passes through the second solenoid valve 1162 and the second shut-off valve 1152 to reach the indoor unit 200. In the indoor unit 200, it exchanges heat with the indoor air and becomes a low-temperature, high-pressure liquid or gas-liquid two-phase refrigerant. It then returns to the outdoor unit 100 through the first shut-off valve 1151. After being throttled and depressurized by the outdoor expansion valve 114, it becomes a low-temperature, low-pressure liquid refrigerant and flows to the outdoor heat exchanger 112 (which acts as an evaporator). In the outdoor heat exchanger 112, it exchanges heat with the outdoor air and becomes a low-temperature, low-pressure gaseous refrigerant. It then returns to the compressor's suction port through the four-way valve 113, completing one heating cycle.

[0107] First air duct: Reference Figure 2 As indicated by the arrow above, the outdoor air, driven by the outdoor fan 3, first passes through the rotor 6 (which is not working), then through the outdoor heat exchanger 112 (which acts as an evaporator), where it absorbs heat and is finally discharged outdoors, completing one heat absorption process of the outdoor heat exchanger 112.

[0108] Operating status 2: Fresh air is on, no humidification is required, fresh air fan 52 is working, and rotor 6 is not working.

[0109] The refrigerant circuit and the air flow in the first air duct are the same as in working state 1 under heating mode. The difference is that there is ventilation in the second air duct.

[0110] Second air duct: Refer to Figure 2 As indicated by the arrow below, the fresh air, driven by the fresh air fan 52, first passes through the fresh air heat exchanger 71 (not working), then through the rotor 6 (not working), and then reaches the fresh air duct 400 through the fresh air outlet 512 and is delivered into the room, completing one fresh air delivery process.

[0111] Operating status 3: Fresh air is on, humidification is required, fresh air fan 52 is working, and rotor 6 is working.

[0112] The status of each valve in the refrigerant circuit under this condition is shown in Table 4.

[0113] Table 4

[0114]

[0115] Refrigerant circuit: Reference Figure 8 High-temperature, high-pressure refrigerant is discharged from the compressor 111 through the exhaust pipe, passes through the switching valve 117, and reaches the fresh air heat exchanger 71 to exchange heat with the fresh air. The refrigerant becomes a low-temperature, high-pressure gas-liquid two-phase refrigerant. Then, it flows to the indoor unit 200 through the third solenoid valve 1163, the four-way valve 113, the second solenoid valve 1162, and the second shut-off valve 1152. In the indoor unit 200, it exchanges heat with the indoor air and becomes a low-temperature, high-pressure liquid or gas-liquid two-phase refrigerant. Then, it returns to the outdoor unit 100 through the first shut-off valve 1151. After passing through the outdoor expansion valve 114, it becomes a low-temperature, low-pressure liquid refrigerant and flows to the outdoor heat exchanger 112 (which acts as an evaporator). In the outdoor heat exchanger 112, it exchanges heat with the outdoor air and becomes a low-temperature, low-pressure gaseous refrigerant. Then, it returns to the compressor's suction port through the four-way valve 113, completing one heating cycle.

[0116] First air duct: Reference Figure 2 As indicated by the arrow above, outdoor air enters the first air duct 15 from the outdoor inlet 13, first passes through the adsorption zone of the rotor 6, where the outdoor air humidity decreases and the temperature increases, and then passes through the outdoor heat exchanger 112, where heat is absorbed by the outdoor heat exchanger 112, and finally discharged to the outside, completing one heat absorption process of the outdoor heat exchanger 112.

[0117] Because the outdoor air passes through the dehumidifier 6 first, the humidity decreases, the temperature increases, and the dew point temperature decreases, making it less likely for the outdoor heat exchanger 112 to frost.

[0118] Second air duct: Refer to Figure 2 As indicated by the arrow below, fresh air enters the second air duct 16 from the outdoor inlet 13. It first passes through the fresh air heat exchanger 71 to become a high-temperature and low-humidity state. Then, when it passes through the regeneration zone of the rotor 6, the moisture inside is removed. The humidity of the fresh air increases and the temperature decreases. It then reaches the fresh air duct 400 from the fresh air outlet 512 and is sent into the room, completing one fresh air heating, humidification and delivery process.

[0119] The following text will describe the signal flow between the components contained in the air conditioner.

[0120] Reference Figure 9 The air conditioner includes a controller 300, a memory 310, and a communication module 320.

[0121] The controller 300 is used to control the compressor 111, valves, outdoor fan 3, impeller 6 and fresh air fan 52 according to the working mode, and to control the operation of the air conditioner based on temperature and humidity information.

[0122] The memory 310 is used to store programs and data related to the operation of the air conditioner; the memory 310 may be implemented by at least one of non-volatile memory (e.g., cache, read-only memory (ROM), programmable ROM (PROM), erasable programmable ROM (EPROM) and flash memory), volatile memory (e.g. random access memory (RAM)) or storage media such as hard disk drive (HDD) and CD-ROM, but is not limited thereto.

[0123] The communication module 320 is used to enable communication between the outdoor unit 100 and the indoor unit 200; for example, the outdoor unit 100 and the indoor unit 200 can share information on temperature and humidity detection through the communication module 320.

[0124] The communication module 320 can be either wired or wireless communication. Wireless communication can use at least one of the following as cellular communication protocols: 5G, LTE, LTE-A Advanced, CDMA, WCDMA, UMTS, Wi-Fi, or GSM. Additionally, wireless communication can include local communication, which may include at least one of Wi-Fi, Bluetooth, or NFC. Wired communication can include at least one of Universal Serial Bus (USB), High Definition Multimedia Interface (HDMI), RS-232, or POTS.

[0125] The air conditioner also includes an input module for receiving user operation commands to the indoor unit 200. The input module may include a push-button switch, membrane switch, or touch panel for receiving operation commands for the indoor unit 200 or the air conditioner, and includes an operation panel configured to receive operation commands for the air conditioner from the user.

[0126] Specifically, the input module can receive user settings for indoor temperature and humidity, as well as the operating mode of the air conditioner.

[0127] In some embodiments of this application, when fresh air is introduced into the room, if the humidity of the fresh air differs significantly from the indoor humidity, it will cause changes in the indoor humidity, thereby affecting the user experience.

[0128] For example, when introducing fresh air into a room, if the humidity of the fresh air is relatively high, it will cause the indoor humidity to increase, and the air conditioner will be needed to dehumidify the fresh air; while if the outdoor air humidity is relatively low, it will cause the indoor humidity to decrease, and the air conditioner will be needed to humidify the fresh air.

[0129] Specifically, the controller 300 can control the air conditioner to perform enhanced dehumidification / humidification operations based on the humidity of the fresh air supply and the indoor humidity.

[0130] The air conditioner also includes a fresh air humidity detection device 330 and an indoor humidity detection device 340.

[0131] The fresh air humidity detection device 330 can be installed at the fresh air outlet 213 to detect the humidity of the fresh air supply.

[0132] The indoor humidity detection device 340 can be installed at the indoor unit intake 211 to detect the humidity of the indoor air.

[0133] The humidity detected by this device can be either relative humidity or air moisture content.

[0134] This application uses moisture content as an example: the fresh air humidity detection device 330 detects the moisture content of the fresh air supply (dsa), and the indoor humidity detection device 340 detects the indoor air moisture content (din).

[0135] <Fresh Air Dehumidification Control in Cooling Mode>

[0136] The following describes the control method in cooling mode. This method ensures that the humidity of the fresh air supply does not exceed the indoor humidity, thus avoiding an increase in indoor humidity when fresh air is introduced.

[0137] Reference Figure 10 When the air conditioner is running in cooling mode, state 3 means that the fresh air fan and impeller are in working condition.

[0138] S11. Determine whether dehumidification enhancement operation is needed based on the moisture content of fresh air supply (dsa) and indoor air moisture content (din). If not, maintain the current state and re-determine every t0 time interval. If so, proceed to S12: Dehumidification enhancement operation.

[0139] In step S11, the specific steps for determining whether enhanced dehumidification operation is needed based on the moisture content of the fresh air supply (dsa) and the moisture content of the indoor air (din) are as follows: determine whether dsa≤din-APr / G is true. If it is true, it means that the humidity of the fresh air is not high, and it is determined that enhanced dehumidification operation is not needed, and the air conditioner maintains its current state; if it is not true, it is determined that enhanced dehumidification operation is needed.

[0140] Where Pr represents the amount of moisture dissipated by the human body indoors, G represents the amount of fresh air supplied, and A is a correction factor.

[0141] S12. The specific steps for enhanced dehumidification operation include:

[0142] S121. Determine whether the exhaust pressure Pd of the compressor meets the preset condition: Pd ≥ P1, where P1 is the first preset critical value in the refrigeration mode of the compressor. For example, P1 = 3.2 Mpa.

[0143] If Pd < P1, then proceed to S122: control the compressor to increase its frequency; if Pd ≥ P1, then proceed to S123: control the outdoor fan to increase its speed by one gear.

[0144] Increasing the frequency of the compressor and increasing the speed of the outdoor fan can both accelerate the dehumidification speed of the air conditioner. Increasing the frequency of the compressor can improve the heat exchange capacity of the fresh air heat exchanger, so that the fresh air can be better cooled and dehumidified when passing through the fresh air heat exchanger; increasing the speed of the outdoor fan can increase the air volume of the outdoor air in the first air duct, and the runner can be regenerated faster under the action of a large amount of outdoor air.

[0145] By increasing the frequency of the compressor or increasing the speed of the outdoor fan, the dehumidification can be accelerated, and the moisture content dsa of the fresh air supply can be reduced.

[0146] In the step of increasing the frequency of the compressor, the frequency of the compressor can be increased according to the preset increase rate β. That is to say, each time the compressor increases its frequency, it increases by β based on the current frequency.

[0147] After each frequency increase of the compressor, it is determined again after a preset time t1 whether dehumidification enhancement operation is required. If so, the frequency of the compressor is increased by β again until the frequency of the compressor reaches the upper limit value of the operating frequency.

[0148] In other embodiments, the frequency of the compressor can also be increased according to a multiple. For example, the multiple is 1.2, the current frequency of the compressor is h, and the frequency of the compressor after increasing the frequency is 1.2h.

[0149] If it is still determined that dehumidification enhancement operation is required when the frequency of the compressor reaches the upper limit value, then proceed to S13: control the outdoor fan to change its direction.

[0150] Similarly, in the step of increasing the speed of the outdoor fan, control the outdoor fan to increase its speed by one gear. After a preset time t2, it is determined again whether dehumidification enhancement operation is required. If so, the speed of the outdoor fan is increased by one gear again until the speed of the outdoor fan reaches the upper limit value of the gear.

[0151] If it is still determined that dehumidification enhancement operation is required when the speed of the outdoor fan reaches the upper limit value, then proceed to S13: control the outdoor fan to change its direction.

[0152] When the outdoor fan changes its direction, the direction of the air flow in the first air duct 15 will change: the outdoor air will enter the first air duct 15 from the outdoor outlet 14, flow through the outdoor heat exchanger 112 for heat exchange, then flow to the runner 6, and finally circulate to the outdoor atmosphere from the outdoor inlet 13.

[0153] Since the outdoor heat exchanger 112 is a condenser, the temperature of the outdoor air will rise when it passes through the outdoor heat exchanger 112. The high temperature outdoor air will then accelerate the regeneration speed of the impeller 6 when it passes through the impeller 6, thereby improving the dehumidification effect of the impeller 6.

[0154] This application achieves the purpose of regenerating the rotor 6 by using the high temperature of the outdoor heat exchanger 112 to condense the outdoor fan 3 in the opposite direction. Compared with the prior art which sets a special heating device on the front side of the rotor 6, this application omits the heating device, making the structure simpler and the cost lower.

[0155] After controlling the outdoor fan to change direction in S13, proceed to S14: If the indoor relative humidity Hra is not greater than the preset lower limit of relative humidity H, i.e., Hra≤H, or if it is determined that no enhanced dehumidification operation is required, then proceed to S15: Control the outdoor fan to change direction again.

[0156] For example, H = 30%; if Hra ≤ 30%, the indoor humidity is too dry. Therefore, to avoid excessive dehumidification, the outdoor fan should be turned normally under this condition.

[0157] If it is determined that no dehumidification enhancement operation is required, it means that the moisture content of the fresh air supply meets the requirements, and the outdoor fan can resume normal rotation.

[0158] After the outdoor fan resumes normal rotation, time t3 is elapsed before returning to step S11 for the next round of judgment.

[0159] It should be noted that under normal cooling operation, the outdoor fan operates in the normal first direction, for example, the first direction is forward. When the compressor frequency is at its maximum and dehumidification is required, or when the outdoor fan speed is at its maximum and dehumidification is required, the outdoor fan reverses direction and rotates in the second direction, i.e., in the opposite direction.

[0160] <Fresh Air Humidification Control in Heating Mode>

[0161] Reference Figure 11 The following describes the control method in heating mode. This control method can ensure that the humidity of the fresh air supply is not less than the indoor humidity, so as to avoid the decrease in indoor humidity when fresh air is introduced.

[0162] When the air conditioner is operating in heating mode (state 3), the fresh air fan and rotor are in operation.

[0163] S21. Based on the humidity content of the fresh air supply (dsa) and the humidity content of the indoor air (din), determine whether humidification enhancement is needed. If not, maintain the current state and re-determine every t0 time interval. If so, proceed with S22: humidification enhancement operation.

[0164] In step S21, the specific steps for determining whether humidification enhancement is needed based on the moisture content of the fresh air supply (dsa) and the moisture content of the indoor air (din) are as follows: determine whether dsa ≥ din - BPr / G is true. If it is true, it is determined that no enhancement operation is needed, and the air conditioner maintains its current state; if it is not true, it is determined that enhancement operation is needed.

[0165] Where Pr represents the amount of moisture dissipated by the human body indoors, G represents the amount of fresh air supplied, and B is a correction factor.

[0166] S22. The specific steps for enhancing humidification operation include:

[0167] S221. Determine whether the compressor's discharge pressure Pd meets the preset condition: Pd≤P2, where P2 is the second preset critical value under the compressor's heating mode, for example, P2=2.0Mpa.

[0168] If Pd≤P2, then proceed with S222: control the compressor to increase its frequency; if Pd>P2, then proceed with S223: control the outdoor fan to increase its speed.

[0169] Increasing the compressor frequency and the outdoor fan speed can both accelerate the humidification speed of an air conditioner. A higher compressor frequency improves the heat exchange capacity of the fresh air heat exchanger, thus accelerating the warming of the fresh air and allowing moisture in the impeller to escape more quickly and enter the room. Conversely, increasing the outdoor fan speed increases the airflow through the first air duct, causing the impeller to absorb more moisture.

[0170] Humidification capacity can be improved by increasing the frequency of the compressor or the speed of the outdoor fan, thereby increasing the moisture content (dsa) of the fresh air supply.

[0171] In the process of increasing the compressor frequency, the compressor frequency can be increased according to a preset increment β. That is, each time the compressor increases its frequency, β is added to the current frequency.

[0172] After each frequency increase, the compressor will determine whether humidification is needed again after a preset time t1. If so, the compressor frequency will increase by β again until the compressor frequency reaches the upper limit of the operating frequency.

[0173] If the compressor frequency reaches the upper limit and it is determined that humidification is still required, then proceed with S23: control the fresh air fan to reduce its speed.

[0174] Similarly, in the step of increasing the outdoor fan speed, the outdoor fan speed is increased by one level, and after a preset time t2, it is determined again whether humidification is needed. If so, the outdoor fan speed is increased by one level again until the outdoor fan speed reaches the upper limit of the level.

[0175] If the outdoor fan speed reaches the upper limit and it is determined that humidification is still needed, then proceed with S23: control the fresh air fan to reduce speed.

[0176] Reducing the speed of the fresh air fan can decrease the volume of fresh air supplied, resulting in a higher absolute humidity in the fresh air supply. Furthermore, the regeneration effect at the impeller will be improved, thereby increasing the moisture content (dsa) of the fresh air supply.

[0177] After each time the fresh air fan lowers its speed by one level, it returns to step S21 after time t3 to perform the next round of judgment.

[0178] In addition, the fresh air fan can reduce the wind speed by a preset ratio α. Each time the wind speed is reduced, the wind speed after the reduction is α times the original speed, where 0 < α < 1.

[0179] In the above control methods, the purpose of air conditioning operation is to ensure that fresh air does not cause an increase in indoor humidity when cooling, and that fresh air does not cause a decrease in indoor humidity when heating.

[0180] <Controlling to prevent frost>

[0181] In some embodiments of this application, to avoid frost formation on the outdoor heat exchanger, this application implements frost prevention control based on outdoor environmental conditions.

[0182] Specifically, refer to Figure 9 The controller 300 can control the power of the electric heating device 72 based on whether the outdoor temperature and humidity are in a frosty zone.

[0183] The air conditioner also includes an outdoor temperature and humidity detection device 350 and a coil temperature detection device 360.

[0184] The outdoor temperature and humidity detection device 350 is located on the windward side of the outdoor heat exchanger and is used to detect the temperature and humidity of the outdoor wind.

[0185] The coil temperature detection device 360 ​​is installed on the coil of the outdoor heat exchanger to detect the temperature Tp of the outdoor heat exchanger.

[0186] Reference Figure 12 Control methods to prevent frost formation on outdoor heat exchangers include:

[0187] S31. In heating mode, determine whether the outdoor temperature and humidity are in the preset frosting zone. The conditions for the frosting zone are that the outdoor temperature Toa ≤ T0 and the outdoor relative humidity Hoa ≥ H0. T0 and H0 are preset values, for example, T0 = 5℃ and H0 = 70%.

[0188] If the area is not prone to frost (i.e., Toa≤5℃ and Hoa≥70%), it means that the outdoor temperature and humidity conditions are unlikely to cause frost formation on the outdoor heat exchanger, and the current state can be maintained.

[0189] If it is in the frost - prone area, that is, when Toa ≤ 5°C and Hoa ≥ 70% hold, it indicates that the outdoor temperature - humidity conditions are likely to cause frosting on the outdoor heat exchanger, and then enter S32.

[0190] S32: Calculate the dew - point temperature TL of the outdoor air before the outdoor heat exchanger.

[0191] Since the dew - point temperature TL can be calculated based on the temperature and humidity detected by the outdoor temperature - humidity detection device 350 and it belongs to the prior art, the specific calculation method will not be elaborated here.

[0192] S33: Determine whether the relationship between the detected value Tp of the coil temperature detection device and the dew - point temperature TL satisfies the preset frost - prone condition: Tp < TL + D, where D is a preset value, for example, D = 1°C.

[0193] If the frost - prone condition is not satisfied, that is, Tp < TL + D does not hold, then maintain the current state;

[0194] If the frost - prone condition is satisfied, that is, Tp < TL + D holds, indicating a high probability of frosting on the outdoor heat exchanger, then enter S34.

[0195] S34: The electric heating device operates.

[0196] When the electric heating device operates, it can increase the regeneration temperature of the runner, so that the moisture of the runner is separated as soon as possible, thereby improving the adsorption capacity of the runner, reducing the outdoor air humidity and increasing the temperature. Moreover, the temperature of the runner will also increase under the action of the heating device, further increasing the temperature of the outdoor air to avoid frosting on the outdoor heat exchanger.

[0197] After the electric heating device is started, after time t, return to S33 to re - judge. If the frost - prone condition is still satisfied, continue to increase the power of the electric heating device, and the power of the electric heating device can be increased from low to high.

[0198] <An embodiment of humidification control>

[0199] When the moisture content of the outdoor air is relatively low, introducing fresh air into the room will cause the indoor humidity to decrease. Therefore, it is necessary to humidify the fresh air.

[0200] Specifically, the controller 300 can control the runner speed, the outdoor fan speed or the power of the electric heating device based on the indoor set humidity and the indoor return air humidity.

[0201] Refer to Figure 13 , the control method of this embodiment includes:

[0202] S41. In heating mode, determine whether the outdoor humidity is in a low humidity zone. The condition for a low humidity zone is the outdoor relative humidity Hoa. <H0。

[0203] If the outdoor humidity is in a low humidity zone, then the outdoor humidity is not in a frosting zone, so there is no need to consider controlling to avoid frosting, and the control should be carried out for the purpose of humidification.

[0204] If the humidity level is not low (Hoa < 70%), it means that the outdoor air has a high humidity level. Introducing fresh air into the room will not reduce the indoor humidity; the current humidity level can be maintained.

[0205] If the area is in a low humidity zone, i.e., Hoa < 70%, it means that the outdoor air has a low humidity content and needs to be humidified. In this case, proceed to S42.

[0206] S42. Determine whether the indoor set humidity exceeds the sum of the indoor return air humidity and the first preset allowable value, i.e., whether Hs≥Hra+M or ds≥dra+N is true.

[0207] Where Hs represents the indoor set relative humidity, Hra represents the indoor return air relative humidity, ds represents the indoor set humidity, dra represents the indoor return air humidity, and M and N are preset values.

[0208] If not, then maintain the current state; if yes, it means that the indoor humidity is relatively low and humidification is needed to reach the user's set indoor humidity, then proceed to S43.

[0209] S43, control the rotor to increase its speed, the outdoor fan to increase its speed, or the electric heating device to operate.

[0210] Increasing the rotation speed of the rotor, increasing the rotation speed of the outdoor fan, or operating the electric heating device can all increase the humidity content of the fresh air. This increases the indoor humidity by introducing fresh air with high humidity into the room, thereby ensuring that the indoor humidity meets the set indoor humidity level.

[0211] Increasing the rotation speed of the impeller and the outdoor fan can both increase the amount of outdoor air flowing through the impeller, thereby allowing the impeller's adsorption area to absorb more moisture to provide humidification for the fresh air.

[0212] The operation of the electric heating device can increase the regeneration temperature of the rotor regeneration zone, thereby allowing the moisture in the regeneration zone to be removed more quickly, thus increasing the humidity content of the fresh air.

[0213] The following describes the follow-up steps for each of the three methods:

[0214] Method 1: Increase the rotation speed of the impeller

[0215] After the rotational speed of the rotor increases, it enters S44 after time t1.

[0216] S44. Determine whether the indoor return air humidity exceeds the sum of the indoor set humidity and the second preset allowable value, i.e., whether Hra≥Hs+X or dra≥ds+Y is true.

[0217] If yes, it means that the indoor return air humidity is close to the indoor set humidity, and the rotor maintains the current speed; if no, it means that the indoor return air humidity is not close to the indoor set humidity, and then enters S45: the rotor speed increases again by one level, and after time t1, it returns to S44 to make the next judgment.

[0218] It should be noted that the first preset allowable value and the second preset allowable value can be the same or different; when they are different, the first preset allowable value can be greater than the second preset allowable value, that is, N>Y, M>X.

[0219] For example, in the case of ds≥dra+N, when this formula holds true, since the first preset allowable value N is relatively large, it indicates that the indoor set humidity is much greater than the indoor return air humidity. In this case, it is necessary to take measures (increase the speed of the rotor, increase the speed of the outdoor fan, or operate the heating device) to speed up the humidification. If the first preset allowable value N is relatively small, there may be a situation where the indoor set humidity is only slightly higher than the indoor return air humidity. In this case, the air conditioner can maintain the current humidification speed to quickly make the indoor return air humidity close to the indoor set humidity, and there is no need to take any further measures to increase the humidification speed.

[0220] Method 2: Increase the speed of the outdoor fan

[0221] After the outdoor fan speed increases, it enters S44 after time t1.

[0222] S44. Determine whether the indoor return air humidity exceeds the sum of the indoor set humidity and the second preset allowable value, i.e., whether Hra≥Hs+X or dra≥ds+Y is true.

[0223] If yes, it means that the indoor return air humidity is close to the indoor set humidity, and the outdoor fan maintains the current speed; if no, it means that the indoor return air humidity is not close to the indoor set humidity, and then proceeds to S46: the outdoor fan speed is increased by one level again, and after time t1, it returns to S44 to make the next round of judgment.

[0224] Method 3: Electric heating device in operation

[0225] The electric heating device starts, and after time t1, it enters S44.

[0226] S44. Determine whether the indoor return air humidity exceeds the sum of the indoor set humidity and the second preset allowable value, i.e., whether Hra≥Hs+X or dra≥ds+Y is true.

[0227] If yes, it means that the indoor return air humidity is close to the indoor set humidity, and the electric heating device maintains its current state; if no, it means that the indoor return air humidity is not close to the indoor set humidity, and then proceeds to S47: the power of the electric heating device is increased by one level, and after time t1, it returns to S44 to perform the next round of judgment.

[0228] <Another embodiment of humidification control>

[0229] To select the optimal humidification method from the three options, refer to... Figure 14 This application also provides the following implementation methods:

[0230] S51. In heating mode, determine whether the outdoor environment is in a low humidity zone. The condition for a low humidity zone is the outdoor relative humidity Hoa. <H0。

[0231] If the region is not in a low-humidity zone (i.e., Hoa < 70% does not hold), the current state can be maintained; if the region is in a low-humidity zone (i.e., Hoa < 70% holds), then proceed to S52.

[0232] S52. Determine whether the indoor set humidity exceeds the sum of the indoor return air humidity and the first preset allowable value, i.e., whether Hs≥Hra+M or ds≥dra+N is true.

[0233] If not, then maintain the current state; if yes, then proceed to S53.

[0234] S53. Determine the number of times the current environmental condition is recorded in the memory.

[0235] If the number of records Z for the current environmental condition satisfies Z≤n, then execute S54, where n≥0.

[0236] The current environmental conditions include outdoor temperature and humidity, and indoor return air humidity. i .

[0237] If the number of times the current environmental condition is recorded, Z, satisfies: n+1≤Z≤n+1+m, then record the current environmental condition and execute S55, where m≥0.

[0238] If the number of times the current environmental condition is recorded, Z, satisfies: n+2+m≤Z≤n+2+m+p, then record the current environmental condition and execute S56, where p≥0.

[0239] If the number of times the current environmental condition is recorded satisfies Z≥n+3+m+p, then execute S57.

[0240] S54. Choose one of the three enhancement methods: increase the speed of the rotary wheel by one level, increase the speed of the outdoor fan by one level, or start the electric heating device. After an interval of t2, calculate and record the return air humidity change rate Δd1 under the current enhancement method.

[0241] S55. Select one of the enhancement methods different from S54 and execute it. After an interval of t2, calculate and record the return air humidity change rate Δd2 under the current enhancement method.

[0242] S56. Select an enhancement method different from S54 and S55 and execute it. After an interval of t2, calculate and record the return air humidity change rate Δd3 under the current enhancement method.

[0243] S57. The enhancement method corresponding to the largest of Δd1, Δd2, and Δd3 in the execution record.

[0244] For example, n = 0, m = 0, p = 0.

[0245] When Z=0, meaning the current environmental condition has not been recorded, proceed to S54 and increase the speed of the rotor by one level; when Z=1, meaning the current environmental condition has been recorded once, proceed to S55 and increase the speed of the outdoor fan by one level; when Z=2, meaning the current environmental condition has been recorded twice, proceed to S56 and start the electric heating device; when Z≥3, meaning the current environmental condition has been recorded three or more times, proceed to S57 and execute the enhancement method corresponding to the largest of Δd1, Δd2, and Δd3 in the records.

[0246] The following describes the follow-up steps for each of the three methods:

[0247] Method 1: Increase the rotation speed of the impeller

[0248] After the rotational speed of the rotor increases by one level, it enters S58 after time t1 (t1≥t2).

[0249] S58. Determine whether the indoor return air humidity exceeds the sum of the indoor set humidity and the second preset allowable value, i.e., whether Hra≥Hs+X or dra≥ds+Y is true.

[0250] If yes, the rotor maintains its current speed; otherwise, proceed to S59.

[0251] S59, the rotation speed of the wheel increases by one level again, and after time t1, it returns to S58 to perform the next round of judgment.

[0252] In this method, the return air humidity change rate Δd1 is calculated according to the following formula:

[0253] Δd1=(dra i+1 -dra i ) / Δw1

[0254] Among them, dra i+1 The humidity content of indoor return air after increasing the rotor speed by one level;

[0255] dra i Moisture content of indoor return air before increasing the rotor speed by one level;

[0256] Δw1 represents the power change before and after the rotor speed adjustment.

[0257] Method 2: Increase the speed of the outdoor fan

[0258] The outdoor fan speed is increased by one level, and after time t1 (t1≥t2), it enters S58.

[0259] S58. Determine whether the indoor return air humidity exceeds the sum of the indoor set humidity and the second preset allowable value, i.e., whether Hra≥Hs+X or dra≥ds+Y is true.

[0260] If yes, the outdoor fan maintains its current speed; otherwise, proceed to S60.

[0261] S60, the outdoor fan speed is increased by one level again, and after time t1, it returns to S58 for the next round of judgment. In this method, the return air humidity change rate Δd2 is calculated according to the following formula:

[0262] Δd2=(dra i+1 -dra i ) / Δw2

[0263] Among them, dra i+1 The indoor return air humidity after increasing the outdoor fan speed by one level; dra i Δw2 represents the indoor return air humidity before the outdoor fan speed is increased by one level; Δw2 represents the power change value before and after the outdoor fan speed adjustment.

[0264] Method 3: Electric heating device in operation

[0265] The electric heating device starts and enters S58 after time t1 (t1≥t2).

[0266] S58. Determine whether the indoor return air humidity exceeds the sum of the indoor set humidity and the second preset allowable value, i.e., whether Hra≥Hs+X or dra≥ds+Y is true.

[0267] If yes, the electric heating device remains in its current state; otherwise, proceed to step S61.

[0268] S61, the power of the electric heating device is increased by one level, and after time t1, it returns to S58 to perform the next round of judgment.

[0269] In this method, the return air humidity change rate Δd3 is calculated according to the following formula:

[0270] Δd3=(dra i+1 -drai ) / Δw3

[0271] Among them, dra i+1 The humidity content of the indoor return air after the electric heating device has been operating; dra i Δw3 represents the humidity of the indoor return air before the electric heating device starts operating; Δw3 represents the power change value before and after the electric heating device starts operating.

[0272] In this application, during the initial stage of the air conditioner's fresh air humidification operation, three enhancement modes are run respectively, and the return air humidity change rate under each enhancement mode is calculated. By comparing the return air humidity change rate, the mode with the best humidification effect can be determined, so that the air conditioner can be operated according to the mode with the best humidification effect in subsequent operation.

[0273] The first concept of this application is to install a rotor 6 on the windward side of the outdoor heat exchanger 112 of the outdoor unit, so that the moisture of the outdoor wind is first absorbed by the rotor 6 before flowing to the outdoor heat exchanger 112, ensuring that the air flowing to the outdoor heat exchanger 112 is dry and low temperature air, thus avoiding the problem of frost forming on the outdoor heat exchanger 112 in winter.

[0274] The second concept of this application is to set up a second air duct in the outdoor unit and set up a fresh air heat exchanger and / or an electric heating device on the windward side of the rotor 6. During heating operation, the fresh air heat exchanger and / or the electric heating device serve as the heat source for the regeneration zone of the rotor 6 to remove moisture from the rotor 6, thereby achieving fresh air humidification while avoiding frost formation on the outdoor heat exchanger 112.

[0275] The third concept of this application is to set up a second air duct in the outdoor unit and to set up a fresh air heat exchanger and / or an electric heating device on the windward side of the rotor 6. During cooling operation, the fresh air can be dehumidified and sent into the indoor unit due to the adsorption effect of the rotor 6.

[0276] The fourth concept of this application is to determine whether enhanced dehumidification / humidification is needed based on a comparison between the humidity of the fresh air supply and the indoor humidity, so that the fresh air does not cause the indoor humidity to rise or fall, thus avoiding changes in indoor humidity while introducing fresh air.

[0277] The fifth concept of this application is that when fresh air is introduced into the room in cooling mode, the outdoor fan 3 rotates in the opposite direction to regenerate the rotor 6 by utilizing the high temperature of the outdoor heat exchanger 112, thereby improving the dehumidification effect of the system on the fresh air. Compared with the prior art, which sets a special heating device on the front side of the rotor 6, this application omits the heating device, making the structure simpler and the cost lower.

[0278] The sixth concept of this application is to make the timing of frost avoidance control more precise by taking whether the outdoor temperature and humidity are in the frost-prone zone as the primary condition for frost avoidance control.

[0279] The seventh concept of this application is to run three enhancement modes in the early stage of the air conditioner's fresh air humidification operation, and calculate the return air humidity change rate under each enhancement mode. By comparing the return air humidity change rate, the mode with the best humidification effect can be determined. Thus, the air conditioner can be operated in the mode with the best humidification effect in the subsequent operation, so that the air conditioner humidifies the fastest.

[0280] The terms "including", "having", etc. are used to specify features, numbers, steps, operations, elements, components, or combinations of features, numbers, steps, operations, elements, and components, but do not exclude the presence or addition of one or more features, elements, steps, operations, components, or combinations of features, numbers, steps, operations, elements, and components.

[0281] Terms such as “unit”, “part”, “block”, “component” and “module” indicate a unit used to perform at least one function or operation. For example, these terms may refer to at least one process processed by at least one piece of hardware (such as a field-programmable gate array (FPGA), application-specific integrated circuit (ASIC)), at least one piece of software stored in a memory or processor.

[0282] The identification codes are used for ease of description, but are not intended to indicate the order of each step. Unless the context clearly indicates otherwise, each step may be performed in a different order than that shown.

[0283] For ease of explanation, the above description has been provided 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. Various modifications and variations can be obtained based on the above teachings. The selection and description of the above embodiments are for the purpose of better explaining the principles and practical applications, thereby enabling those skilled in the art to better utilize the described embodiments and various different variations of embodiments suitable for specific use considerations.

Claims

1. An air conditioner, characterized in that, include: Outdoor unit; The outdoor unit includes: The casing has a first air duct inside, with both ends of the first air duct connected to the outside. An outdoor heat exchanger is installed inside the first air duct and is used to exchange heat with the outdoor air inside the first air duct. An outdoor fan is used to drive the flow of outdoor air within the first air duct. A compressor is used to compress refrigerant; The housing also includes a second air duct, which is connected to a fresh air duct for supplying fresh air into the room. The outdoor unit also includes: A rotor is rotatably connected to the housing, the rotor having a first portion located in the first air duct and a second portion located in the second air duct, the first portion being located on the windward side of the outdoor heat exchanger when the outdoor fan rotates in a first direction; A heating device is provided in the second air duct and located on the windward side of the rotor. The heating device is a fresh air heat exchanger, or the heating device is a combination of a fresh air heat exchanger and an electric heating device. The air conditioner also includes: Fresh air humidity detection device, used to detect the humidity of fresh air supply; Indoor humidity detection device, used to detect the humidity of the indoor environment; Controller, used for: Based on the detection values ​​from the fresh air humidity detection device and the indoor humidity detection device, it is determined whether enhanced operation is required. If enhanced operation is required, the compressor frequency is increased or the outdoor fan speed is increased. Increasing the compressor frequency can improve the heat exchange capacity of the fresh air heat exchanger. In cooling mode, when the compressor has increased its frequency to the upper limit of the operating frequency and still needs to be operated more strongly, or when the outdoor fan speed has increased to the upper limit of the fan speed and still needs to be operated more strongly, the outdoor fan is controlled to rotate in a second direction opposite to the first direction, so that the outdoor air is first heated by the outdoor heat exchanger and then flows to the impeller, thereby removing the moisture absorbed by the impeller.

2. The air conditioner according to claim 1, characterized in that, The controller is used for: When the outdoor fan is rotating in the second direction, if the indoor relative humidity is not greater than the preset lower limit of relative humidity or no additional operation is required, the outdoor fan will be controlled to return to the first direction.

3. The air conditioner according to claim 1, characterized in that, Also includes: Fresh air fans are used to drive fresh air into the room; The controller is used for: In heating mode, when the compressor has increased its frequency to the upper limit of the operating frequency and still needs to be operated more strongly, or when the outdoor fan speed has increased to the upper limit of the fan speed and still needs to be operated more strongly, the fresh air fan speed is reduced.

4. The air conditioner according to claim 3, characterized in that, In the step of controlling the fresh air fan to reduce its speed, the fresh air fan reduces its speed and returns after a preset time t3 to determine whether it is necessary to strengthen the operation. If not, the fresh air fan is controlled to maintain its current speed; if so, the fresh air fan is controlled to continue to reduce its speed.

5. The air conditioner according to claim 1, characterized in that, The controller is used for: In cooling mode, it is determined whether dsa≤din-APr / G is true. If it is true, it is determined that no additional operation is needed and the air conditioner maintains its current state; if it is not true, it is determined that additional operation is needed. In heating mode, it is determined whether dsa≥din-BPr / G is true. If it is true, it is determined that no further operation is needed and the air conditioner maintains its current state; if it is not true, it is determined that further operation is needed. Where dsa represents the moisture content of fresh air, din represents the moisture content of indoor air, Pr represents the moisture dissipation from the human body indoors, G represents the fresh air supply volume, and A and B are correction coefficients.

6. The air conditioner according to claim 1, characterized in that, The controller is used for: When enhanced operation is required, in cooling mode, it is determined whether the compressor's discharge pressure is not less than the first preset critical value. If not, the compressor frequency is increased; if so, the outdoor fan speed is increased. In heating mode, it is determined whether the compressor's discharge pressure is not greater than the second preset critical value. If so, the compressor frequency is increased. If not, then control the outdoor fan to increase its speed.

7. The air conditioner according to claim 6, characterized in that, In the step of controlling the compressor frequency increase, the compressor frequency is increased, and after a preset time t1, the system returns to determine whether the operation needs to be strengthened. If so, the compressor frequency is increased until it reaches the upper limit of the operating frequency. If not needed, keep the compressor frequency unchanged.

8. The air conditioner according to claim 6, characterized in that, In the step of controlling the outdoor fan to increase its speed, the outdoor fan is controlled to increase its speed, and after a preset time t2, it is returned to determine whether the operation needs to be strengthened. If so, the outdoor fan is controlled to increase its speed again until it reaches the upper limit of the wind speed. If not required, keep the outdoor fan speed constant.

9. A method for controlling an air conditioner, characterized in that, The air conditioner includes an outdoor unit; The outdoor unit includes: The casing has a first air duct inside, with both ends of the first air duct connected to the outside. An outdoor heat exchanger is installed inside the first air duct and is used to exchange heat with the outdoor air inside the first air duct. An outdoor fan is used to drive the flow of outdoor air within the first air duct. A compressor is used to compress refrigerant; The housing also includes a second air duct, which is connected to a fresh air duct for supplying fresh air into the room. The outdoor unit also includes: A rotor is rotatably connected to the housing, the rotor having a first portion located in the first air duct and a second portion located in the second air duct, the first portion being located on the windward side of the outdoor heat exchanger when the outdoor fan rotates in a first direction; A heating device is provided in the second air duct and located on the windward side of the rotor. The heating device is a fresh air heat exchanger, or the heating device is a combination of a fresh air heat exchanger and an electric heating device. The control method includes: Detect the humidity of the fresh air supply and the humidity of the indoor environment; The system determines whether enhanced operation is needed based on the humidity of the fresh air supply and the humidity of the indoor environment. If enhanced operation is deemed necessary, the compressor frequency is increased or the outdoor fan speed is increased. Increasing the compressor frequency can improve the heat exchange capacity of the fresh air heat exchanger. In cooling mode, when the compressor has increased its frequency to the upper limit of the operating frequency and still needs to be operated more strongly, or when the outdoor fan speed has increased to the upper limit of the fan speed and still needs to be operated more strongly, the outdoor fan is controlled to rotate in a second direction opposite to the first direction, so that the outdoor air is first heated by the outdoor heat exchanger and then flows to the impeller, thereby removing the moisture absorbed by the impeller.

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