Air conditioner and control method thereof

Abstract

The invention discloses an air conditioner and a control method thereof, and belongs to the technical field of air treatment. An air conditioner includes: an outdoor unit; the outdoor unit comprises a first air duct; the outdoor heat exchanger is arranged in the first air duct; the outdoor fan is used for driving outdoor air in the first air duct to flow; a compressor; a second air duct is further arranged in the shell, is connected with a fresh air pipe and is used for feeding fresh air into a room; the rotating wheel is provided with a first part located in the first air duct and a second part located in the second air duct, and the first part is located on the windward side of the outdoor heat exchanger when the outdoor fan rotates in the first direction; the controller is used for judging whether strengthening operation is needed or not based on the detection value of the fresh air humidity detection device and the detection value of the indoor humidity detection device, and controlling the compressor to increase the frequency or controlling the outdoor fan to increase the rotating speed when it is judged that strengthening operation is needed. According to the air conditioner, fresh air humidification / dehumidification can be achieved while frosting of the outdoor heat exchanger is avoided.

Description

Technical Field

[0001] The present application relates to the field of air treatment technology, and in particular to an air conditioner and a control method thereof. Background Art

[0002] Air conditioners are devices that use refrigeration cycles to control temperature and humidity suitable for human activities. When the air conditioner is in heating mode in winter, the outdoor heat exchanger acts as an evaporator. When the evaporation temperature is below 0°C, frost easily forms on its surface.

[0003] A common defrosting method in the prior art is to perform defrosting by reversing the refrigeration system.

[0004] This defrosting method takes a long time to prepare, absorbs heat from the room during defrosting, and the air outlet temperature rises slowly after defrosting, causing serious fluctuations in indoor temperature and affecting user comfort. Summary of the invention

[0005] The present application provides an air conditioner and a control method thereof, which utilizes an adsorption wheel to dehumidify outdoor air before passing the air through an outdoor heat exchanger, thereby preventing the outdoor heat exchanger from frosting.

[0006] In one aspect of the present application, an air conditioner comprises: an outdoor unit; the outdoor unit comprises: a shell, in which a first air duct is provided, and both ends of the first air duct are connected to the outdoors respectively; an outdoor heat exchanger is provided in the first air duct and is used to exchange heat with the outdoor air in the first air duct; an outdoor fan is used to drive the outdoor air in the first air duct to flow; a compressor is used to compress refrigerant; wherein a second air duct is also provided in the shell, and the second air duct is connected to a fresh air duct for supplying fresh air to the room; the outdoor unit also comprises: a rotor, rotatably connected to the shell, the rotor having a first part located in the first air duct, and a second part located in the second air duct, the first part being located on the windward side of the outdoor heat exchanger when the outdoor fan rotates in a first direction; the air conditioner also comprises: a fresh air humidity detection device, which is used to detect the supply air humidity of the fresh air; an indoor humidity detection device, which is used to detect the humidity of the indoor environment; a controller, which is used to: judge whether it is necessary to strengthen the operation based on the detection value of the fresh air humidity detection device and the detection value of the indoor humidity detection device, and control the compressor to increase the frequency or control the outdoor fan to increase the speed when it is judged that the operation needs to be strengthened.

[0007] In some embodiments, the controller is used to: in cooling mode, when the compressor has been upgraded 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 been increased to the upper limit of the wind 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 wind is first heated by the outdoor heat exchanger and then flows to the wheel, thereby separating the moisture absorbed by the wheel.

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

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

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

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

[0012] In some embodiments, the controller is used to: in cooling mode, determine whether dsa≤din-APr / G is established. If so, it is determined that no enhanced operation is required and the air conditioner maintains the current state; if not, it is determined that enhanced operation is required; in heating mode, determine whether dsa≥din-BPr / G is established. If so, it is determined that no enhanced operation is required and the air conditioner maintains the current state; if not, it is determined that enhanced operation is required; wherein dsa represents the humidity content of fresh air, din represents the humidity content of indoor air, Pr represents the moisture dissipation of human body indoors, G represents the air supply volume of fresh air, and A and B are correction coefficients.

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

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

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

[0016] In another aspect of the present application, a control method for an air conditioner, the air conditioner includes an outdoor unit; the outdoor unit includes: a shell, in which a first air duct is provided, and both ends of the first air duct are respectively connected to the outdoors; an outdoor heat exchanger is provided in the first air duct and is used to exchange heat with the outdoor wind in the first air duct; an outdoor fan is used to drive the outdoor wind in the first air duct to flow; a compressor is used to compress refrigerant; wherein a second air duct is also provided in the shell, and a fresh air duct connected to the second air duct is used to supply fresh air to the room; the outdoor unit also includes: a rotor, rotatably connected to the shell, the rotor has a first part located in the first air duct, and a second part located in the second air duct, the first part is 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 air humidity of the fresh air and the humidity of the indoor environment; judging whether it is necessary to intensify the operation based on the supply air humidity of the fresh air and the humidity of the indoor environment, and controlling the compressor to increase the frequency or controlling the outdoor fan to increase the speed when it is judged that the operation needs to be intensified. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 shows a schematic diagram of an air conditioner according to some embodiments;

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

[0019] Figure 3 shows an internal top view of an outdoor unit of an air conditioner according to other embodiments;

[0020] Figure 4 shows an exploded view of an outdoor unit of an air conditioner according to some embodiments;

[0021] Figure 5 A schematic diagram of a refrigerant circuit of an air conditioner in cooling mode without dehumidification of fresh air according to some embodiments is shown;

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

[0023] Figure 7 A schematic diagram of a refrigerant circuit of an air conditioner in heating mode without humidification of fresh air according to some embodiments is shown;

[0024] Figure 8A schematic diagram of a refrigerant circuit for humidifying fresh air in a heating mode of an air conditioner according to some embodiments is shown;

[0025] Fig. 9 shows a control signal flow block diagram of an air conditioner according to some embodiments;

[0026] Fig.10 A control flow chart of fresh air dehumidification of an air conditioner according to some embodiments is shown;

[0027] Fig.11 A control flow chart of fresh air humidification of an air conditioner according to some embodiments is shown;

[0028] Fig.12 A control flow chart for avoiding frost formation of an air conditioner according to some embodiments is shown;

[0029] Fig.13 A control flow chart of indoor humidification of an air conditioner according to some embodiments is shown;

[0030] Fig.14 A flow chart of optimization control of indoor humidification of an air conditioner according to some embodiments is shown. DETAILED DESCRIPTION

[0031] In order to make the purpose and implementation method of the present application clearer, the exemplary implementation method of the present application will be clearly and completely described below in conjunction with the drawings in the exemplary embodiments of the present application. Obviously, the described exemplary embodiments are only part of the embodiments of the present application, rather than all the embodiments.

[0032] Embodiments of the present application will be described in detail below, examples of which are shown in the accompanying drawings.

[0033] Reference Figure 1 The air conditioner of the embodiment of the present 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 suction port 211, which is arranged on the top surface of the indoor unit body 210 and is used to collect indoor air to enter the indoor unit body 210; and an indoor unit exhaust port 212, which is arranged at a lower front position of the indoor unit body 210 and is used to exhaust the air after heat exchange. The above is an illustration based on the indoor unit 200 being a wall-mounted structure. In other embodiments, for example, the indoor unit 200 is a vertical cabinet structure, then the indoor unit suction port 211 is arranged at the back of the indoor unit body 210, and the indoor unit exhaust port 212 is arranged 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. Usually, the fan chamber 11 and the compressor chamber 12 are arranged in a transverse manner.

[0037] The outdoor heat exchanger 112 and the outdoor fan 3 in the outdoor unit 100 are arranged in the fan chamber 11 , and the compressor 111 , the outdoor expansion valve 114 and the like of the outdoor unit 100 are arranged 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 housing 1. The outdoor inlet 13 connects the fan chamber 11 and the outdoor atmosphere, and the outdoor outlet 14 connects the fan chamber 11 and the outdoor atmosphere.

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

[0040] The two ends of the first air duct 15 are connected to the outdoor inlet 13 and the outdoor outlet 14 respectively, and the outdoor heat exchanger 112 and the outdoor fan 3 are both arranged in the first air duct 15. The outdoor fan 3 allows the outdoor air to circulate between the first air duct 15 and the outdoor atmosphere, and the outdoor heat exchanger 112 is used to exchange heat with the outdoor air in the first air duct 15. The outdoor air enters the first air duct 15 from the outdoor inlet 13, exchanges heat with the outdoor heat exchanger 112, and is blown to the outside from the outdoor outlet 14.

[0041] One end of the second air duct 16 is connected to the outdoor inlet 13, and the other end of the second air duct 16 is a fresh air outlet 512. The fresh air outlet 512 is connected to the fresh air duct 400, and the fresh air duct 400 extends into the room to achieve communication between the second air duct 16 and the room.

[0042] The air conditioner may include a fresh air blower 52 for driving the air in the second air duct 16 to flow indoors. For ease of description, the air in the first air duct 15 is also referred to as outdoor air, and the air in the second air duct 16 is also referred to as fresh air.

[0043] The fresh air fan 52 may be disposed in the second air duct 16 , so that the fresh air in 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 fresh air duct 400 can directly deliver fresh air to the room; or, Figure 1 The indoor end of the fresh air duct 400 can also be connected to the indoor unit 200, and then the fresh air is supplied into the room through the fresh air supply port 213 on the indoor unit 200.

[0045] In an embodiment in which the fresh air duct 400 supplies air through the indoor unit 200 , the fresh air blower 52 may also be disposed in the indoor unit 200 .

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

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

[0048] The rotor 6 is rotatably connected in 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 switches between the adsorption zone and the regeneration zone.

[0049] It can be understood that when the outdoor wind 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 portion of the wheel 6 located in the first air duct 15 is the regeneration zone, and the portion located in the second air duct 16 is the adsorption zone; when the outdoor wind 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 portion of the wheel 6 located in the first air duct 15 is the adsorption zone, and the portion located in the second air duct 16 is the regeneration zone.

[0050] Reference Figure 4 Since the adsorption zone and the regeneration zone will change according to the air temperature in the air duct, for the convenience of description, the part of the wheel 6 located in the first air duct 15 is called the first part 61, and the part of the wheel 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 may be set to be no greater than 1 / 3 of the first part 61 .

[0052] Exemplarily, 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 as regular as possible, thereby making the appearance of the fresh air heat exchanger 71 adapted to the second air duct 16 more regular, reducing the difficulty of manufacturing.

[0053] The outdoor heat exchanger 112 has a larger area to ensure the heat exchange capacity on the outdoor side, so 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 arranged in the second air duct 16 and located on the windward side of the rotor 6, and is used to heat the fresh air in the second air duct 16, so that the temperature of the fresh air increases, thereby separating the moisture from the regeneration zone of the rotor 6.

[0055] The heating device 7 can be a fresh air heat exchanger, an electric heating device, or a combination of the two. That is, in one embodiment, the windward side of the runner 6 is only provided with a fresh air heat exchanger 71, and the fresh air heat exchanger 71 is used as a condenser when the air conditioner is in heating operation; in another embodiment, the windward side of the runner 6 is only provided with an electric heating device 72, such as an electric heating wire, etc., and the electric heating device 72 is operated by energizing the electric heating device 72; in another embodiment, the windward side of the runner 6 is provided with 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 runner 6.

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

[0057] The present application sets a rotor 6 on the windward side of the outdoor heat exchanger 112 so that the outdoor wind first absorbs moisture in the rotor 6 and then flows to the outdoor heat exchanger 112, thereby ensuring that the air flowing to the outdoor heat exchanger 112 is dry and low-temperature air, thereby avoiding the problem of frosting of 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, and the outlet end of the second air duct 16 is also connected to the outdoors. Outdoor air enters the second air duct 16 from the outdoor inlet 13, passes through the heating device 7 and the wheel 6, and then circulates to the outdoors.

[0059] According to an embodiment of the present 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 runner 6 to the outdoor inlet 13, and the second partition 18 extends from the windward side edge of the second part of the runner 6 to the side wall where the outdoor outlet 14 is located in the direction away from the runner 6. In this way, the first partition 17, the second partition 18 and the top wall of the shell 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 shell 1 ; except for the second air duct 16 in the fan chamber 11 , the remaining part constitutes the first air duct 15 .

[0062] In some embodiments of the present application, reference Figure 3 The outdoor unit 100 includes a fresh air module 5 , which includes a fresh air casing 51 and a fresh air fan 52 , and the fresh air fan 52 is disposed in the fresh air casing 51 .

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

[0064] The fresh air module 5 can be set at an upper position in the fan chamber 11 to facilitate the fresh air outlet 512 to be exposed from the top of the shell 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 chamber 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 side edge of the second part of the impeller 6 to the outdoor inlet 13, and the second partition 18 extends from the windward side edge of the second part of the impeller 6 to the fresh air inlet end of the fresh air module 5. In this way, the first partition 17, the second partition 18 and the top wall of the shell 1 and the partition plate 10 form a second air duct 16.

[0066] In some embodiments, the outdoor entrance 13 may be configured to be divided into two, one connected to the first air duct 15 as an entrance for outdoor air, and the other connected to the second air duct 16 as an 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 wind 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 the cooling mode; the outdoor expansion valve 114 decompresses the refrigerant guided to the outdoor heat exchanger 112 or flowing out of the outdoor heat exchanger 112.

[0068] The compressor 111 receives external electric energy to compress low-pressure gaseous refrigerant to high pressure.

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

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

[0071] In addition, a first stop valve 1151 and a second stop valve 1152 are respectively provided on the gas pipe and the liquid pipe between the outdoor unit 100 and the indoor unit 200. The first stop valve 1151 is located between the outdoor heat exchanger 112 and the indoor unit 200, and the second stop 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 in series with the first stop valve 1151 and then connected to one end of the indoor unit 200, the E tube of the four-way valve 113 is connected in series with the second stop valve 1152 and then connected to the other end of the indoor unit 200, 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 the present 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 stop valve 1152 .

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

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

[0076] The output end of the fresh air heat exchanger 71 is divided into two branches, the first branch is connected to the D pipe of the four-way valve 113, and the second branch is connected to the input end of the compressor 111. The first branch is connected in series with the third solenoid valve 1163, and the second branch is connected in series with the fourth solenoid valve 1164.

[0077] In other embodiments, the three-way valve can replace the above-mentioned switching valve 117, one interface of the three-way valve is connected to the input end of the fresh air heat exchanger 71, the second interface of the three-way valve is connected to the output end of the compressor 111, and the third interface of the three-way valve is connected between the second solenoid valve 1162 and the second stop valve 1152.

[0078] The following is an introduction to the working mode of the air conditioner in combination with the refrigerant circuit:

[0079] Cooling mode

[0080] Working state 1: the fresh air function is not turned on, and the fresh air fan 52 and the impeller 6 are not working.

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

[0082] Table 1

[0083]

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

[0085] The 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: Refer to Figure 5 The arrows in the figure indicate the flow direction of the refrigerant. The high-temperature and 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 (as a condenser) to exchange heat with the outdoor wind. The refrigerant becomes a low-temperature and high-pressure liquid or gas-liquid two-phase refrigerant, and then passes through the outdoor expansion valve 114 to throttle and reduce the pressure to become a low-temperature and low-pressure liquid refrigerant, and then flows to the indoor unit 200 through the first stop valve 1151, exchanges heat with the indoor air in the indoor unit 200 to become a low-temperature and low-pressure gaseous refrigerant, and then returns to the outdoor unit 100 through the second stop valve 1152, passes through the second solenoid valve 1162 and the four-way valve 113 to return to the suction port of the compressor, completing a refrigeration cycle.

[0087] First air channel: reference Figure 2 The arrow above indicates the flow direction of the outdoor wind. Driven by the outdoor fan 3, the outdoor wind first passes through the impeller 6 (not working), 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 wind, and finally is discharged to the outdoors through the outdoor outlet 14, completing the heat dissipation process of the outdoor heat exchanger 112.

[0088] Working state 2: Fresh air is turned on and dehumidification is not required, the fresh air fan is working, and the impeller is not working.

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

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

[0091] Working state 3: Fresh air is turned on and dehumidification is required, the fresh air fan is working, and the impeller is working.

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

[0093] Table 2

[0094]

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

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

[0097] Refrigerant circuit: Refer to Figure 6 , the arrow indicates the flow direction of the refrigerant. The high-temperature and 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 and high-pressure liquid or gas-liquid two-phase refrigerant, and then passes through the outdoor expansion valve 114 to throttle and reduce the pressure to become a low-temperature and low-pressure liquid refrigerant, and then flows to the indoor unit 200 through the first stop valve 1151, exchanges heat with the indoor air in the indoor unit 200 to become a low-temperature and low-pressure gaseous refrigerant, and then returns to the outdoor unit 100 through the second stop valve 1152, and then flows to the switching valve 117, and flows to the fresh air heat exchanger 71 (acting as an evaporator) through the switching valve 117 to exchange heat with the fresh air, and then passes through the fourth solenoid valve 1164 back to the suction port of the compressor, completing a refrigeration cycle.

[0098] First air channel: reference Figure 2 As shown by the arrow above, the outdoor wind first passes through the regeneration zone of the rotor 6 driven by the outdoor fan 3 to regenerate the moisture in 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 wind, and finally is discharged to the outdoors through the outdoor outlet 14, completing the heat dissipation process of the outdoor heat exchanger 112.

[0099] Second air channel: reference Figure 2 As shown by the arrow below, the fresh air is driven by the fresh air fan 52 and first passes through the fresh air heat exchanger 71 (evaporator) to be cooled and cooled to a low temperature and high humidity state. Then, the moisture carried by the fresh air when passing through the adsorption area of ​​the rotor 6 is adsorbed inside the rotor. The fresh air then reaches the fresh air duct 400 through the fresh air outlet 512 and is delivered into the room, completing a fresh air cooling, dehumidification and transportation process.

[0100] When the air conditioner of the present application introduces fresh air in cooling mode, the fresh air can be cooled and dehumidified.

[0101] Heating mode

[0102] Working state 1: the fresh air is not turned on, and the fresh air fan 52 and the impeller 6 are not working.

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

[0104] Table 3

[0105]

[0106] Refrigerant circuit: Refer to Figure 7 The arrows in the figure indicate the flow direction of the refrigerant. The high-temperature and 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 stop valve 1152 to reach the indoor unit 200, exchanges heat with the indoor air in the indoor unit 200, and the refrigerant becomes a low-temperature and high-pressure liquid or gas-liquid two-phase refrigerant, and then returns to the outdoor unit 100 through the first stop valve 1151, and is throttled and reduced in pressure by the outdoor expansion valve 114 to become a low-temperature and low-pressure liquid refrigerant, and then flows to the outdoor heat exchanger 112 (serving as an evaporator), exchanges heat with the outdoor air in the outdoor heat exchanger 112 to become a low-temperature and low-pressure gaseous refrigerant, and then passes through the four-way valve 113 back to the suction port of the compressor, completing a heating cycle.

[0107] First air channel: reference Figure 2 As shown in the upper middle arrow, the outdoor wind, driven by the outdoor fan 3, first passes through the impeller 6 (not working), then passes through the outdoor heat exchanger 112 (acting as an evaporator), and is absorbed by the outdoor heat exchanger 112. The wind is finally discharged to the outdoors, completing a heat absorption process of the outdoor heat exchanger 112.

[0108] Working state 2: fresh air is turned on, no humidification is required, the fresh air fan 52 is working, and the impeller 6 is not working.

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

[0110] Second air channel: reference Figure 2 As shown by the lower middle arrow, the fresh air, driven by the fresh air fan 52, first passes through the fresh air heat exchanger 71 (not working), then passes through the impeller 6 (not working), and then reaches the fresh air duct 400 through the fresh air outlet 512 and is delivered into the room, thus completing a fresh air delivery process.

[0111] Working state 3: fresh air is turned on, humidification is required, the fresh air fan 52 is working, and the impeller 6 is working.

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

[0113] Table 4

[0114]

[0115] Refrigerant circuit: Refer to Figure 8 The high-temperature and high-pressure refrigerant is discharged from the compressor 111 through the exhaust pipe, passes through the switching valve 117, reaches the fresh air heat exchanger 71 to exchange heat with the fresh air, and the refrigerant becomes a low-temperature and high-pressure gas-liquid two-phase refrigerant, and then passes through the third solenoid valve 1163, the four-way valve 113, the second solenoid valve 1162, and the second stop valve 1152 to flow to the indoor unit 200, and exchanges heat with the indoor air in the indoor unit 200 to become a low-temperature and high-pressure liquid or gas-liquid two-phase refrigerant, and then returns to the outdoor unit 100 through the first stop valve 1151, and passes through the throttling and pressure reduction of the outdoor expansion valve 114 to become a low-temperature and low-pressure liquid refrigerant, and then flows to the outdoor heat exchanger 112 (serving as an evaporator), and exchanges heat with the outdoor air in the outdoor heat exchanger 112 to become a low-temperature and low-pressure gaseous refrigerant, and then passes through the four-way valve 113 to return to the suction port of the compressor, completing a heating cycle.

[0116] First air channel: reference Figure 2 As shown in the upper middle arrow, the outdoor wind enters the first air duct 15 from the outdoor inlet 13, and first passes through the adsorption area of ​​the wheel 6. At this time, the outdoor wind humidity is reduced and the temperature is increased. Then, the outdoor wind passes through the outdoor heat exchanger 112, and the heat is absorbed by the outdoor heat exchanger 112, and finally discharged to the outdoors, completing a heat absorption process of the outdoor heat exchanger 112.

[0117] Since the outdoor wind first passes through the wheel 6 for dehumidification, the humidity decreases, the temperature increases, and the dew point temperature decreases, making it difficult for the outdoor heat exchanger 112 to frost.

[0118] Second air channel: reference Figure 2 As shown by the lower middle arrow, the fresh air enters the second air duct 16 from the outdoor inlet 13, first passes through the fresh air heat exchanger 71 to become a high-temperature and low-humidity state, and then passes through the regeneration area of ​​the wheel 6 to separate the moisture inside. The fresh air humidity then increases and the temperature decreases, and then reaches the fresh air duct 400 from the fresh air outlet 512 and is delivered into the room, completing a fresh air heating, humidification and delivery process.

[0119] Hereinafter, signal flows between components included in the air conditioner will be described.

[0120] Reference Fig. 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, the valve, the outdoor fan 3, the impeller 6 and the fresh air fan 52 according to the working mode, and is used to control the operation of the air conditioner based on the 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 can be implemented by at least one of a non-volatile memory (e.g., a cache, a read-only memory (ROM), a programmable ROM (PROM), an erasable programmable ROM (EPROM) and a flash memory), a volatile memory (e.g., a random access memory (RAM)), or a storage medium such as a hard disk drive (HDD) and a CD-ROM, but is not limited thereto.

[0123] The communication module 320 is used to realize the communication between the outdoor unit 100 and the indoor unit 200; for example, the detection information of the temperature and humidity by the outdoor unit 100 and the indoor unit 200 can be shared through the communication module 320.

[0124] The communication module 320 can be wired communication or wireless communication. The wireless communication can use at least one of the fifth generation (5G) mobile communication, long term evolution (LTE), advanced LTE (LTE-A), code division multiple access (CDMA), wideband CDMA (WCDMA), universal mobile telecommunications system (UMTS), wireless broadband (WiBro) or global mobile communication system (GSM) as a cellular communication protocol; in addition, the wireless communication may include local communication, which may include at least one of wireless fidelity (WiFi), Bluetooth or near field communication (NFC); ​​wired communication may include at least one of universal serial bus (USB), high definition multimedia interface (HDMI), recommended standard 232 (RS-232) or plain old telephone service (POTS).

[0125] The air conditioner further includes an input module for receiving a user's operation instruction for the indoor unit 200. The input module may include a button-type switch, a membrane switch, or a touch panel for receiving an operation command for the indoor unit 200 or the air conditioner, and includes an operation panel configured to receive an operation command for the air conditioner from a user.

[0126] Specifically, the input module can receive the user's set values ​​for indoor temperature and humidity and the operating mode of the air conditioner.

[0127] In some embodiments of the present application, when fresh air is introduced into the room, if the humidity of the fresh air is significantly different from the indoor humidity, it may cause a change in the indoor humidity, thereby affecting the user experience.

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

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

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

[0131] The fresh air humidity detection device 330 may be disposed at the fresh air supply outlet 213 to detect the fresh air supply humidity.

[0132] The indoor humidity detection device 340 may be disposed at the indoor unit suction port 211 to detect the humidity of the indoor air.

[0133] The humidity detected by the detection device here can be relative humidity or air moisture content.

[0134] This application is introduced by taking humidity content as an example: the fresh air humidity detection device 330 detects the fresh air supply humidity content dsa, and the indoor humidity detection device 340 detects the indoor air humidity content din.

[0135] <Fresh air dehumidification control in cooling mode>

[0136] The following introduces a control method in cooling mode, which can ensure that the humidity of fresh air supply is not greater than the indoor humidity, so as to avoid an increase in indoor humidity when introducing fresh air.

[0137] Reference Fig.10 When the air conditioner operates in working state 3 in cooling mode, the fresh air fan and the impeller are in working state.

[0138] S11. Determine whether dehumidification enhancement operation is required based on the fresh air supply humidity content dsa and the indoor air humidity content din. If not, maintain the current state and re-determine every t0 time interval; if necessary, proceed to S12: dehumidification enhancement operation.

[0139] In step S11, the specific steps of judging whether dehumidification enhancement operation is needed based on the fresh air supply humidity content dsa and the indoor air humidity content din are as follows: judging whether dsa≤din-APr / G holds true; if so, it means that the fresh air humidity is not high, and it is judged that dehumidification enhancement operation is not needed, and the air conditioner maintains the current state; if not, it is judged that dehumidification enhancement operation is needed.

[0140] Among them, Pr represents the amount of moisture dissipated by the human body in the room, G represents the amount of fresh air supplied, and A is the correction coefficient.

[0141] S12, the steps of dehumidification enhancement operation specifically include:

[0142] S121. Determine whether the exhaust pressure Pd of the compressor satisfies 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] Both increasing the frequency of the compressor and increasing the speed of the outdoor fan can 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, resulting in a decrease in the moisture content dsa of the fresh air supply.

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

[0147] After each time the compressor increases its frequency, 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 in multiples. 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 rotation 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 rotation direction.

[0152] When the outdoor fan changes its rotation direction, the wind direction of 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 increase when passing through the outdoor heat exchanger 112 . The high-temperature outdoor air will accelerate the regeneration speed of the wheel 6 when passing through the wheel 6 , thereby improving the dehumidification effect of the wheel 6 .

[0154] The present application achieves the purpose of regenerating the impeller 6 by utilizing the condensation high temperature of the outdoor heat exchanger 112 through the reverse rotation of the outdoor fan 3. Compared with the prior art in which a special heating device is provided on the front side of the impeller 6, the present application omits the heating device, has a simpler structure, and is relatively low in cost.

[0155] After the outdoor fan is controlled to change direction in S13, S14 is performed: if the indoor relative humidity Hra is not greater than the preset relative humidity lower limit H, that is, Hra≤H or it is determined that dehumidification enhancement operation is not required, either of the two conditions is met, then enter S15: control the outdoor fan to change direction again.

[0156] For example, H=30%; if Hra≤30%, the indoor humidity is too dry. Therefore, in order to avoid excessive dehumidification, the normal rotation direction of the outdoor fan is restored under this condition.

[0157] If it is determined that enhanced dehumidification operation is not needed, 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, the process returns to step S11 after time t3 to perform the next round of judgment.

[0159] It should be noted that when the air conditioner is in normal cooling operation, the outdoor fan operates in a normal first direction, for example, the first direction is forward; when the frequency of the compressor is the highest and dehumidification enhancement operation is required, or the speed of the outdoor fan is the highest and dehumidification enhancement operation is required, the outdoor fan reverses and rotates in a second direction, i.e., in the reverse direction.

[0160] <Fresh air humidification control in heating mode>

[0161] Reference Fig.11 The following introduces a control method in heating mode, which can ensure that the humidity of fresh air supply is not less than the indoor humidity, so as to avoid the reduction of indoor humidity when introducing fresh air.

[0162] When the air conditioner operates in working state 3 in the heating mode, the fresh air fan and the impeller are in working state.

[0163] S21. Determine whether humidification enhancement operation is required based on the fresh air supply humidity content dsa and the indoor air humidity content din. If not, maintain the current state and re-determine every t0 time; if necessary, proceed to S22: humidification enhancement operation.

[0164] In step S21, the specific steps of judging whether humidification enhanced operation is needed based on the fresh air supply humidity content dsa and the indoor air humidity content din are: judging whether dsa≥din-BPr / G is established; if so, judging that enhanced operation is not needed and the air conditioner maintains the current state; if not, judging that enhanced operation is needed.

[0165] Among them, Pr represents the amount of moisture dissipated by the human body in the room, G represents the amount of fresh air supplied, and B is the correction coefficient.

[0166] S22, the steps of humidification enhancement operation specifically include:

[0167] S221. Determine whether the exhaust pressure Pd of the compressor meets a preset condition: Pd≤P2, where P2 is a second preset critical value in the compressor heating mode, for example, P2=2.0 MPa.

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

[0169] The compressor frequency increase and the outdoor fan speed increase can both speed up the humidification speed of the air conditioner. The compressor frequency increase can increase the heat exchange capacity of the fresh air heat exchanger, thereby speeding up the temperature rise of the fresh air, allowing the moisture in the rotor to escape faster and enter the room; the outdoor fan speed increase can increase the outdoor air volume in the first air duct, allowing the rotor to absorb more moisture.

[0170] The 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 step of increasing the frequency of the compressor, the frequency of the compressor may be increased according to a preset increase β, that is, each time the frequency of the compressor is increased, β is increased on the basis of the current frequency.

[0172] After each frequency increase of the compressor, after a preset time t1, it is determined again whether humidification enhancement operation is required. If necessary, the frequency of the compressor is increased by β again until the frequency of the compressor reaches the upper limit of the operating frequency.

[0173] If it is determined that humidification enhancement operation is still needed when the frequency of the compressor reaches the upper limit, S23 is performed: the fresh air fan is controlled to reduce speed.

[0174] Similarly, in the step of increasing the speed of the outdoor fan, the speed of the outdoor fan is controlled to increase by one level. After a preset time t2, it is determined again whether humidification enhancement operation is needed. If necessary, the speed of the outdoor fan is increased by one level again until the speed of the outdoor fan reaches the upper limit of the level.

[0175] If the rotation speed of the outdoor fan reaches the upper limit and it is determined that humidification enhancement operation is still required, S23 is performed: the fresh air fan is controlled to reduce speed.

[0176] Slowing down the speed of the fresh air fan can reduce the fresh air supply volume. The absolute humidity of the fresh air supply is higher, and the regeneration effect at the wheel will be improved, so the moisture content dsa of the fresh air supply will increase.

[0177] Each time the fresh air fan is lowered by one gear, it returns to step S21 after t3 time to perform the next round of judgment.

[0178] In addition, the fresh air fan can also reduce the wind speed according to a preset ratio α, and the wind speed after each reduction is α times the wind speed before the speed reduction, where 0<α<1.

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

[0180] <Controls to avoid frost>

[0181] In some embodiments of the present application, in order to avoid frost on the outdoor heat exchanger, the present application performs control to avoid frost based on outdoor environmental conditions.

[0182] Specifically, refer to Fig. 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 frost-prone area.

[0183] The air conditioner further 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 arranged 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 disposed on the coil of the outdoor heat exchanger and is used to detect the temperature Tp of the outdoor heat exchanger.

[0186] Reference Fig.12 , the control methods to avoid frost on the outdoor heat exchanger include:

[0187] S31. In the heating mode, determine whether the outdoor temperature and humidity are in a preset frost-prone zone. The condition of the frost-prone zone is that the outdoor temperature Toa≤T0 and the outdoor relative humidity Hoa≥H0, where T0 and H0 are preset values, for example, T0=5°C and H0=70%.

[0188] If it is not in a frosting-prone area, that is, Toa≤5℃ and Hoa≥70% are not true, it means that the outdoor temperature and humidity conditions are not likely to cause frost 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 and humidity conditions are likely to cause frosting on the outdoor heat exchanger, and then it enters 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 and 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 possibility 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 rotary wheel, so that the moisture of the rotary wheel is separated as soon as possible, thereby improving the adsorption capacity of the rotary wheel, reducing the humidity of the outdoor air and increasing its temperature. Moreover, the temperature of the rotary wheel 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, it returns to S33 to re - judge. If the frost - prone condition is still satisfied, then continue to increase the power of the electric heating device, and the power of the electric heating device can increase from low to high.

[0198] <An embodiment of humidity 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 rotation speed of the rotary wheel, the rotation speed of the outdoor fan or the power of the electric heating device based on the indoor set humidity and the indoor return air humidity.

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

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

[0203] If the outdoor humidity is in the low humidity area, the outdoor humidity is not in the frost-prone area, and there is no need to consider the control to avoid frost, but to carry out the control for the purpose of humidification.

[0204] If it is not in a low humidity area, that is, Hoa<70% does not hold true, which means that the humidity content of the outdoor air is high, and the introduction of fresh air into the room will not reduce the indoor humidity, so the current state can be maintained.

[0205] If it is in a low humidity area, that is, Hoa<70%, it means that the humidity content of the outdoor air is low and the fresh air needs to be humidified, then enter S42.

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

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

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

[0209] S43, controlling the rotating wheel to increase the rotating speed, increasing the rotating speed of the outdoor fan, or operating the electric heating device.

[0210] The moisture content of fresh air can be increased by increasing the rotation speed of the impeller, increasing the rotation speed of the outdoor fan or operating the electric heating device. The indoor humidity can be increased by introducing high-humidity fresh air into the room, thereby making the indoor humidity meet the indoor set humidity.

[0211] Increasing the speed of the impeller and the speed of the outdoor fan can increase the amount of outdoor air flowing through the impeller, so that the adsorption area of ​​the impeller absorbs more moisture to provide humidification for the fresh air.

[0212] The operation of the electric heating device can increase the regeneration temperature of the regeneration zone of the wheel, thereby allowing the moisture in the regeneration zone to be separated faster to increase the moisture content of the fresh air.

[0213] The following are the subsequent steps of the three methods:

[0214] Method 1: Increase the speed of the wheel

[0215] After the rotation speed of the wheel is increased, the process enters S44 after time t1 has passed.

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

[0217] If so, it means that the indoor return air humidity is close to the indoor set humidity, and the wheel maintains the current speed; if not, it means that the indoor return air humidity is not close to the indoor set humidity, and then enter S45: the wheel speed is increased by one level again, and after t1 time, it returns to S44 for the next round of judgment.

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

[0219] For example, in ds≥dra+N, when this formula holds true, since the first preset allowable value N is larger, 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 speed; if the first preset allowable value N is smaller, there may be a situation where the indoor set humidity is less than the indoor return air humidity. At this time, the air conditioner can quickly make the indoor return air humidity close to the indoor set humidity by maintaining the current humidification speed, and there is no need to take measures to increase the humidification speed.

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

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

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

[0223] If so, it means that the indoor return air humidity is close to the indoor set humidity, and the outdoor fan maintains the current speed; if not, it means that the indoor return air humidity is not close to the indoor set humidity, then enter S46: the speed of the outdoor fan is increased by one level again, and after t1 time, return to S44 for the next round of judgment.

[0224] Mode 3: Electric heating device works

[0225] The electric heating device is started, and after time t1 has passed, the process enters S44.

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

[0227] If so, it means that the indoor return air humidity is close to the indoor set humidity, and the electric heating device maintains the current state; if not, it means that the indoor return air humidity is not close to the indoor set humidity, then enter S47: the power of the electric heating device is increased by one level, and after t1 time, return to S44 for the next round of judgment.

[0228] <Another Embodiment of Humidification Control>

[0229] In order to select the best humidification method among the three methods, refer to Fig.14 , the present application also provides the following implementation modes:

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

[0231] If it is not in the low humidity area, that is, Hoa<70% does not hold, maintain the current state; if it is in the low humidity area, that is, Hoa<70% holds, enter S52.

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

[0233] If not, maintain the current state; if so, enter S53.

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

[0235] If the number of records Z of the current environmental condition satisfies: Z≤n, S54 is executed, where n≥0.

[0236] Among them, the current environmental conditions include the temperature and humidity of the outdoor environment, the indoor return air humidity, and the i .

[0237] If the number of times Z that the current environmental condition is recorded satisfies: n+1≤Z≤n+1+m, the current environmental condition is recorded and S55 is executed, wherein m≥0.

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

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

[0240] S54, executing one of the three enhancement methods: increasing the speed of the impeller by one gear, increasing the speed of the outdoor fan by one gear, and starting 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 modes different from S54 to execute, and after an interval of t2, calculate and record the return air humidity change rate Δd2 under the current enhancement mode.

[0242] S56, select a reinforcement mode different from S54 and S55 to execute, and after an interval of t2, calculate and record the return air humidity change rate Δd3 under the current reinforcement mode.

[0243] S57, executing the reinforcement method corresponding to the largest one among Δd1, Δd2, and Δd3 in the record.

[0244] Exemplarily, n=0, m=0, p=0.

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

[0246] The following are the subsequent steps of the three methods:

[0247] Method 1: Increase the speed of the wheel

[0248] After the rotation speed of the wheel is increased by one level, the process enters S58 after a time period of 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, that is, whether Hra≥Hs+X or dra≥ds+Y is established.

[0250] If so, the wheel maintains the current rotation speed; if not, enter S59.

[0251] S59, the rotation speed of the wheel is increased by one gear again, and after t1 time, the process returns to S58 for 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 It is the indoor return air humidity content after the rotor speed is increased by one level;

[0255] dra i It is the indoor return air humidity content before the rotor speed is increased by one level;

[0256] Δw1 is the power change before and after the wheel speed is adjusted.

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

[0258] The speed of the outdoor fan is increased by one level, and after a time period of t1 (t1≥t2), the process 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, that is, whether Hra≥Hs+X or dra≥ds+Y is established.

[0260] If so, the outdoor fan maintains the current speed; if not, enter S60.

[0261] S60, the speed of the outdoor fan is increased by one gear again, and after t1 time, the process 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 It is the humidity content of indoor return air after the outdoor fan speed is increased by one level;dra i is the indoor return air humidity before the outdoor fan speed is increased by one level; Δw2 is the power change value before and after the outdoor fan speed is adjusted.

[0264] Mode 3: Electric heating device works

[0265] The electric heating device is started, and after time t1 (t1≥t2) the process enters S58.

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

[0267] If so, the electric heating device maintains the current state; if not, enter S61.

[0268] S61, the power of the electric heating device is increased by one level, and after t1 time, the process returns to S58 for 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 It is the humidity content of indoor return air after the electric heating device works;dra i is the indoor return air humidity before the electric heating device starts working; Δw3 is the power change value before and after the electric heating device is started.

[0272] In the present application, in the early stage of the fresh air humidification operation of the air conditioner, three enhancement modes are respectively operated, and the return air humidity change rate under various enhancement modes is calculated. By comparing the return air humidity change rate, the best humidification method can be obtained, so that the air conditioner can be operated in the subsequent operation according to the best humidification method.

[0273] The first concept of the present application is to set a rotor 6 on the windward side of the outdoor heat exchanger 112 of the outdoor unit, so that the moisture in the outdoor wind is first absorbed by the rotor 6 and then flows to the outdoor heat exchanger 112, ensuring that the air flowing to the outdoor heat exchanger 112 is dry and low-temperature air, thereby avoiding the problem of frosting of the outdoor heat exchanger 112 in winter.

[0274] The second concept of the present application is to set a second air duct in the outdoor unit and set a fresh air heat exchanger and / or an electric heating device on the windward side of the wheel 6. During heating operation, the fresh air heat exchanger and / or the electric heating device are used as the heat source in the regeneration zone of the wheel 6 to separate the moisture in the wheel 6, thereby achieving fresh air humidification while avoiding frosting of the outdoor heat exchanger 112.

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

[0276] The fourth concept of the present application is to determine whether enhanced dehumidification / humidification operation is needed based on the comparison between the fresh air supply humidity and the indoor humidity, so that the fresh air will not cause the indoor humidity to increase / decrease, and the change of indoor humidity is avoided while introducing fresh air.

[0277] The fifth concept of the present application is that when fresh air is introduced into the room in cooling mode, the reverse rotation of the outdoor fan 3 is used to regenerate the impeller 6 by utilizing the condensation 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 in which a special heating device is provided on the front side of the impeller 6, the present application omits the heating device, has a simpler structure, and is relatively low in cost.

[0278] The sixth concept of the present application makes the timing of entering the frost avoidance control more accurate by taking whether the outdoor environment temperature and humidity are in a frost-prone area as the primary condition for frost avoidance control.

[0279] The seventh concept of the present application is to respectively operate three enhanced modes in the early stage of the fresh air humidification operation of the air conditioner, and calculate the return air humidity change rate under various enhanced modes. By comparing the return air humidity change rates, the best humidification method can be obtained, so that the air conditioner can be operated in the subsequent operation according to the best humidification method, making the humidification speed of the air conditioner the fastest.

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

[0281] Terms such as "unit", "part", "block", "member" and "module" indicate a unit for processing at least one function or operation. For example, these terms may refer to at least one process processed by at least one hardware (such as a field programmable gate array (FPGA), an application specific integrated circuit (ASIC)), at least one software stored in a memory or a processor.

[0282] The identification codes are used for convenience of description, but are not intended to indicate the order of each step. Unless the context clearly indicates otherwise, each step can be implemented in an order different from the order shown.

[0283] For the convenience of explanation, the above description has been made in conjunction with specific embodiments. However, the above exemplary discussion is not intended to be exhaustive or limit the embodiments to the specific forms disclosed above. Based on the above teachings, various modifications and variations can be obtained. The selection and description of the above embodiments are to better explain the principles and practical applications, so that those skilled in the art can better use the embodiments and various different variations of the embodiments suitable for specific use considerations.

Claims

1. An air conditioner, characterized in that: include: Outdoor unit; The outdoor unit comprises: A housing, wherein a first air duct is disposed therein, and two ends of the first air duct are respectively connected to the outside of the room; an outdoor heat exchanger, disposed in the first air duct, for exchanging heat with outdoor air in the first air duct; An outdoor fan, used to drive the outdoor wind to flow in the first air duct; compressor, used to compress the refrigerant; Wherein, a second air duct is further provided in the shell, and the second air duct is connected to a fresh air duct for supplying fresh air into the room; The outdoor unit also includes: a rotating wheel rotatably connected to the housing, the rotating wheel 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 a windward side of the outdoor heat exchanger when the outdoor fan rotates in a first direction; The air conditioner also includes: Fresh air humidity detection device, used to detect the fresh air supply humidity; Indoor humidity detection device, used to detect the humidity of indoor environment; Controller for: Whether enhanced operation is required is determined based on the detection value of the fresh air humidity detection device and the detection value of the indoor humidity detection device, and when it is determined that enhanced operation is required, the compressor is controlled to increase frequency or the outdoor fan is controlled to increase speed.

2. The air conditioner according to claim 1, characterized in that: The controller is used to: In cooling mode, when the compressor has been upgraded 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 been increased to the upper limit of the wind 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 wind is first heated by the outdoor heat exchanger and then flows to the wheel, thereby separating the moisture absorbed by the wheel.

3. The air conditioner according to claim 2, characterized in that: The controller is used to: During the process of the outdoor fan rotating in the second direction, when the indoor relative humidity is not greater than the preset relative humidity lower limit or no enhanced operation is required, the rotation direction of the outdoor fan is controlled to return to the first direction.

4. The air conditioner according to claim 1, characterized in that: Also includes: Fresh air fan, used to drive fresh air to flow indoors; The controller is used to: In heating mode, when the compressor has been increased to the upper limit of the operating frequency and still needs to be operated more vigorously, or when the speed of the outdoor fan has been increased to the upper limit of the wind speed and still needs to be operated more vigorously, the fresh air fan is controlled to reduce its speed.

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

6. The air conditioner according to claim 1, characterized in that: The controller is used to: In cooling mode, it is determined whether dsa≤din-APr / G is established. If so, it is determined that no enhanced operation is required and the air conditioner maintains the current state; if not, it is determined that enhanced operation is required; In the heating mode, it is determined whether dsa≥din-BPr / G is established. If so, it is determined that no enhanced operation is required and the air conditioner maintains the current state; if not, it is determined that enhanced operation is required; Among them, dsa represents the humidity content of fresh air, din represents the humidity content of indoor air, Pr represents the amount of moisture dissipated by the human body indoors, G represents the air supply volume of fresh air, and A and B are correction coefficients.

7. The air conditioner according to claim 1, characterized in that: The controller is used to: When the operation needs to be strengthened, in the cooling mode, it is determined whether the exhaust pressure of the compressor is not less than the first preset critical value. If not, the compressor is controlled to increase the frequency; if so, the outdoor fan is controlled to increase the speed; In the heating mode, determining whether the exhaust pressure of the compressor is not greater than a second preset critical value, and if so, controlling the compressor to increase the frequency; If not, the outdoor fan is controlled to increase the speed.

8. The air conditioner according to claim 7, characterized in that: In the step of controlling the compressor to increase the frequency, the compressor is controlled to increase the frequency, and after a preset time t1, it is returned to determine whether the operation needs to be strengthened. If necessary, the compressor is controlled to continue to increase the frequency until it reaches the upper limit value of the operating frequency; If not required, keep the compressor frequency unchanged.

9. The air conditioner according to claim 7, characterized in that: In the step of controlling the outdoor fan to increase the speed, the outdoor fan is controlled to increase the speed, and after a preset time t2, it is returned to determine whether the operation needs to be strengthened. If necessary, the outdoor fan is controlled to increase the speed again until it reaches the upper limit value of the wind gear; If not necessary, keep the speed of the outdoor fan unchanged.

10. A method for controlling an air conditioner, characterized in that: The air conditioner includes an outdoor unit; The outdoor unit comprises: A housing, wherein a first air duct is disposed therein, and two ends of the first air duct are respectively connected to the outside of the room; an outdoor heat exchanger, disposed in the first air duct, for exchanging heat with outdoor air in the first air duct; An outdoor fan, used to drive the outdoor wind to flow in the first air duct; compressor, used to compress the refrigerant; Wherein, a second air duct is further provided in the shell, and the second air duct is connected to a fresh air pipe for supplying fresh air into the room; The outdoor unit also includes: a rotating wheel rotatably connected to the housing, the rotating wheel 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 a windward side of the outdoor heat exchanger when the outdoor fan rotates in a first direction; The control method comprises: Detect the humidity of fresh air supply and indoor environment; Whether enhanced operation is required is determined based on the supply humidity of the fresh air and the humidity of the indoor environment, and when it is determined that enhanced operation is required, the compressor is controlled to increase the frequency or the outdoor fan is controlled to increase the speed.

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