Air conditioner

Abstract

An air conditioner (1000) comprises an outdoor unit (100), at least one indoor unit (200), an electronic expansion valve (300) and a controller (91). The outdoor unit (100) comprises a compressor (110), an outdoor heat exchanger (120) and an indoor heat exchanger (210). The compressor (110) compresses a refrigerant so as to drive the refrigerant to circulate in the air conditioner (1000); the outdoor heat exchanger (120) is used for liquefying or vaporizing a refrigerant; at least one indoor unit (200) is connected with the outdoor unit (100), and each indoor unit (200) comprises an indoor heat exchanger (210). The indoor heat exchanger (210) performs the other one of liquefying or vaporizing the refrigerant. The electronic expansion valve (300) is connected with the indoor heat exchanger (210) and the outdoor heat exchanger (120) and used for adjusting the flow of a refrigerant flowing between the outdoor heat exchanger (120) and the indoor heat exchanger (210). The controller (91) is configured to read the temperature difference; the supercooling degree of the electronic expansion valve (300) is determined according to the temperature difference value; calculating a supercooling degree difference value; according to the supercooling degree difference value, the target opening degree of the electronic expansion valve (300) is determined; and adjusting the opening degree of the electronic expansion valve (300) to the target opening degree.

Description

air conditioner

[0001] This application claims priority to the Chinese patent application with application number 202211008849.4 filed on August 22, 2022; priority to the Chinese patent application with application number 202211015066.9 filed on August 23, 2022; priority to the Chinese patent application with application number 202222221157.X filed on August 23, 2022, the entire contents of which are incorporated by reference into this application. Technical Field

[0002] The present disclosure relates to the technical field of household appliances, and in particular to an air conditioner. Background Art

[0003] With rising living standards, multi-split air conditioning systems have become increasingly commonplace in households. Besides demanding excellent cooling and heating performance, users are also concerned about user comfort. Noise reduction is a crucial aspect of improving the comfort of multi-split systems.

[0004] The multi-split air conditioning system includes an outdoor unit and multiple indoor units. The outdoor unit and multiple indoor units are all equipped with electronic expansion valves to adjust the flow of refrigerant in the pipeline.

[0005] Summary of the Invention

[0006] In one aspect, an air conditioner is provided. The air conditioner includes an outdoor unit, at least one indoor unit, an electronic expansion valve, and a controller. The outdoor unit includes a compressor, an outdoor heat exchanger, and an indoor heat exchanger. The compressor is configured to compress a refrigerant to drive the refrigerant to circulate in the air conditioner; the outdoor heat exchanger is configured to liquefy or vaporize the refrigerant; the at least one indoor unit is connected to the outdoor unit, and each indoor unit includes an indoor heat exchanger. The indoor heat exchanger is configured to liquefy or vaporize the refrigerant. The electronic expansion valve is connected to the indoor heat exchanger and the outdoor heat exchanger, respectively, and is configured to regulate the flow of the refrigerant flowing between the outdoor heat exchanger and the indoor heat exchanger. The controller is configured to: read a temperature difference, which is the difference between the temperature of the middle part of the indoor heat exchanger and the outlet temperature; determine the subcooling of the electronic expansion valve based on the temperature difference; calculate the subcooling difference, which is the difference between the subcooling and the subcooling setting value; determine the target opening of the electronic expansion valve based on the subcooling difference; adjust the opening of the electronic expansion valve to the target opening to reduce the proportion of gas-phase refrigerant and reduce the refrigerant flow noise.

[0007] In another aspect, an air conditioner is provided. The air conditioner includes an outdoor unit, at least one indoor unit, an electronic expansion valve, a regulating device, and a controller. The outdoor unit includes a compressor, an outdoor heat exchanger, and an indoor heat exchanger; the compressor is configured to compress refrigerant to drive the refrigerant to circulate within the air conditioner. The outdoor heat exchanger is configured to either liquefy or vaporize the refrigerant. The at least one indoor unit is connected to the outdoor unit, and each indoor unit includes an indoor heat exchanger configured to either liquefy or vaporize the refrigerant. The electronic expansion valve is connected to the indoor heat exchanger and the outdoor heat exchanger and is configured to regulate the refrigerant flow between the outdoor heat exchanger and the indoor heat exchanger. The regulating device is connected to the electronic expansion valve and is configured to reduce the impact of the gaseous refrigerant on the electronic expansion valve to reduce refrigerant flow noise. The regulating device includes a bypass pipe and a one-way valve. The bypass pipe is disposed on one side of the inlet pipe of the electronic expansion valve, with a first end of the bypass pipe connected to the inlet pipe and a second end of the bypass pipe connected to the valve body of the electronic expansion valve. The one-way valve is disposed on the bypass pipe and is configured to conduct air in a unidirectional manner from the inlet pipe to the valve body via the bypass pipe. The controller is configured to respond to a mode control instruction and read the operating mode carried in the mode control instruction, and to open the one-way valve if the operating mode is heating mode. BRIEF DESCRIPTION OF THE DRAWINGS

[0008] To more clearly illustrate the technical solutions of the present disclosure, the following briefly introduces the drawings required for use in some embodiments of the present disclosure. Obviously, the drawings described below are only drawings of some embodiments of the present disclosure, and those skilled in the art can also derive other drawings based on these drawings. Furthermore, the drawings described below are schematic diagrams and are not intended to limit the actual dimensions of the products, actual processes of the methods, actual timing of signals, and the like involved in the embodiments of the present disclosure.

[0009] FIG1 is a structural diagram of an air conditioner according to some embodiments;

[0010] FIG2 is a structural diagram of another air conditioner according to some embodiments;

[0011] FIG3 is a flow chart of a control method for reducing refrigerant flow noise of an indoor electronic expansion valve according to some embodiments;

[0012] FIG4 is a structural diagram of an indoor heat exchanger according to some embodiments;

[0013] FIG5 is a refrigerant pressure-enthalpy diagram according to some embodiments;

[0014] FIG6 is a flow chart of a method for controlling an indoor electronic expansion valve according to some embodiments;

[0015] FIG7 is a flow chart of another indoor electronic expansion valve control method according to some embodiments;

[0016] FIG8 is a flow chart of another indoor electronic expansion valve control method according to some embodiments;

[0017] FIG9 is a structural block diagram of an indoor electronic expansion valve control device according to some embodiments;

[0018] FIG10 is a structural diagram of another air conditioner according to some embodiments;

[0019] FIG11 is a structural diagram of a refrigerant system according to some embodiments;

[0020] FIG12 is a structural diagram of an adjustment device according to some embodiments;

[0021] FIG13 is a flow chart of a control method of an adjustment device according to some embodiments;

[0022] FIG14 is a flow chart of another method for controlling an adjustment device according to some embodiments;

[0023] FIG15 is a flow chart of another method for controlling an adjusting device according to some embodiments;

[0024] FIG16 is a flow chart of another method for controlling an adjusting device according to some embodiments;

[0025] FIG17 is a block diagram of a controller according to some embodiments.

[0026] Description of the drawings: 1000 - air conditioner; 100 - outdoor unit; 110 - compressor; 111 - exhaust port; 120 - outdoor heat exchanger; 200 - indoor unit; 210 - indoor heat exchanger; 300 - expansion valve; 310 - outdoor electronic expansion valve; 320 - indoor electronic expansion valve; 32 - inlet pipe; 33 - outlet pipe; 34 - bypass pipe; 35 - check valve; 36 - valve needle; 400 - four-way reversing valve; C - first port; D - second port; S - third port; E - fourth port; 500 - stop valve; 501 - liquid-side stop valve; 502 - gas-side stop valve; 600 - fan; 601 - outdoor fan; 602 - indoor fan; 700 - gas-liquid separator; 20 - temperature sensor; 21 - first temperature sensor; 22 - second temperature sensor; 91 - controller; 92 - memory; 93 - processor; 94 - communication interface. DETAILED DESCRIPTION

[0027] The following will be combined with the accompanying drawings to clearly and completely describe the technical solutions in some embodiments of the present disclosure. Obviously, the embodiments described are only some embodiments of the present disclosure, not all embodiments. Based on the embodiments provided by the present disclosure, all other embodiments obtained by ordinary technicians in this field are within the scope of protection of the present disclosure.

[0028] Unless the context requires otherwise, throughout the specification and claims, the term "comprise" and its other forms, such as the third person singular form "comprises" and the present participle form "comprising", are to be interpreted as open and inclusive, that is, "including, but not limited to". In the description of the specification, the terms "one embodiment", "some embodiments", "exemplary embodiments", "example", "specific example" or "some examples" are intended to indicate that the particular features, structures, materials or characteristics associated with the embodiment or example are included in at least one embodiment or example of the present disclosure. The schematic representation of the above terms does not necessarily refer to the same embodiment or example. In addition, the particular features, structures, materials or characteristics may be included in any one or more embodiments or examples in any appropriate manner.

[0029] In the following, the terms "first" and "second" are used for descriptive purposes only and should not be understood to indicate or imply relative importance or implicitly specify the number of the technical features indicated. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include one or more of the features. In the description of the embodiments of the present disclosure, unless otherwise specified, "plurality" means two or more.

[0030] When describing some embodiments, the expressions "coupled" and "connected" and their derivatives are used. For example, when describing some embodiments, the term "connected" may be used to indicate that two or more components are in direct physical or electrical contact with each other. For another example, when describing some embodiments, the term "coupled" may be used to indicate that two or more components are in direct physical or electrical contact. However, the term "coupled" or "communicatively coupled" may also refer to two or more components that are not in direct contact with each other, but still cooperate or interact with each other. The embodiments disclosed herein are not necessarily limited to the contents of this document.

[0031] “At least one of A, B and C” has the same meaning as “at least one of A, B or C” and both include the following combinations of A, B and C: A only, B only, C only, the combination of A and B, the combination of A and C, the combination of B and C, and the combination of A, B and C.

[0032] “A and / or B” includes the following three combinations: A only, B only, and a combination of A and B.

[0033] The use of "adapted to" or "configured to" herein is intended to be open and inclusive language that does not exclude devices adapted or configured to perform additional tasks or steps.

[0034] Additionally, the use of “based on” is meant to be open and inclusive, as a process, step, calculation, or other action “based on” one or more stated conditions or values ​​may, in practice, be based on additional conditions or values ​​beyond those stated.

[0035] As used herein, "about," "substantially," or "approximately" includes the stated value and an average value that is within an acceptable range of deviation from the particular value as determined by one of ordinary skill in the art taking into account the measurements in question and the errors associated with the measurement of the particular quantity (i.e., the limitations of the measurement system).

[0036] Figure 1 is a structural diagram of an air conditioner according to some embodiments, and Figure 2 is another structural diagram of an air conditioner according to some embodiments. As shown in Figures 1 and 2, some embodiments of the present disclosure provide an air conditioner 1000, which includes a compressor 110, an outdoor heat exchanger 120, an indoor heat exchanger 210, an expansion valve 300, a four-way reversing valve 400, a stop valve 500, a fan 600 and a gas-liquid separator 700.

[0037] In some embodiments of the present disclosure, the air conditioner 1000 includes four operating modes, namely, heating mode, cooling mode, dehumidification mode and air supply mode. The heating mode means that the air conditioner 1000 heats the indoor environment, and the cooling mode means that the air conditioner 1000 cools the indoor environment. The dehumidification mode means that the air conditioner 1000 dehumidifies the indoor environment temperature. The air supply mode means that the air conditioner 1000 increases the indoor air flow and has no obvious cooling or heating effect on the indoor environment. It should be noted that, in some embodiments, the air conditioner 1000 may also include other operating modes, such as a cooling and dehumidification mode, which is not limited by the present disclosure.

[0038] The air conditioner 1000 includes an outdoor unit 100 and an indoor unit 200. The outdoor unit 100 of the air conditioner 1000 includes a compressor 110 and an outdoor heat exchanger 120, and the indoor unit 200 of the air conditioner 1000 includes an indoor heat exchanger 210. The air conditioner 1000 also includes an expansion valve 300, and at least one of the outdoor unit 100 and the indoor unit 200 is provided with the expansion valve 300.

[0039] The compressor 110, the condenser (the indoor heat exchanger 210 or the outdoor heat exchanger 120), the expansion valve 300, and the evaporator (the outdoor heat exchanger 120 or the indoor heat exchanger 210) perform the refrigerant cycle of the air conditioner 1000. The refrigerant cycle includes a series of processes involving compression, condensation, expansion, and evaporation, and circulates the refrigerant to the conditioned side.

[0040] The indoor heat exchanger 210 is configured to either liquefy or vaporize the refrigerant by exchanging heat between the indoor air and the refrigerant transmitted through the indoor heat exchanger 210. The outdoor heat exchanger 120 is configured to either liquefy or vaporize the refrigerant by exchanging heat between the outdoor air and the refrigerant transmitted through the outdoor heat exchanger 120. For example, when the air conditioner 1000 is operating in cooling mode, the indoor heat exchanger 210 operates as an evaporator, so that the refrigerant, after dissipating heat through the outdoor heat exchanger 120, absorbs heat from the indoor air through the indoor heat exchanger 210 and evaporates. When the air conditioner 1000 is in heating mode, the indoor heat exchanger 210 operates as a condenser, so that the refrigerant, after absorbing heat through the outdoor heat exchanger 210, dissipates heat to the indoor air through the indoor heat exchanger 210 and condenses.

[0041] The expansion valve 300, which may be an electronic valve, is connected between the outdoor heat exchanger 120 and the indoor heat exchanger 210. The expansion valve 300 includes an outdoor machine electronic expansion valve (EVO) 310 and an indoor machine electronic expansion valve (EVI) 320. The opening of the electronic expansion valve 300 regulates the pressure of the refrigerant flowing through the outdoor heat exchanger 120 and the indoor heat exchanger 210, thereby adjusting the refrigerant flow rate between the outdoor heat exchanger 120 and the indoor heat exchanger 210. The flow rate and pressure of the refrigerant flowing between the outdoor heat exchanger 120 and the indoor heat exchanger 210 will affect the heat exchange performance of the outdoor heat exchanger 120 and the indoor heat exchanger 210.

[0042] It should be noted that the opening of the electronic expansion valve 300 is adjustable to control the flow rate and pressure of the refrigerant flowing through the electronic expansion valve 300. For example, when the opening of the electronic expansion valve 300 is reduced, the flow resistance of the refrigerant through the electronic expansion valve 300 increases; when the opening of the electronic expansion valve 300 is increased, the flow resistance of the refrigerant through the electronic expansion valve 300 decreases. Thus, even if the states of other components of the air conditioner 1000 remain unchanged, the refrigerant flow rate to the indoor heat exchanger 210 or the outdoor heat exchanger 120 will also change when the opening of the electronic expansion valve 300 changes.

[0043] Compressor 110 compresses the low-temperature, low-pressure gas-phase refrigerant and discharges the compressed high-temperature, high-pressure gas-phase refrigerant, which then flows into the condenser. The condenser condenses the high-temperature, high-pressure gas-phase refrigerant into a high-pressure liquid-phase refrigerant, releasing heat into the surrounding environment during the condensation process. The expansion valve 300 expands the high-pressure liquid-phase refrigerant into a low-pressure gas-liquid two-phase refrigerant. The evaporator absorbs heat from the surrounding environment and evaporates the low-pressure gas-liquid two-phase refrigerant to form a low-temperature, low-pressure gas-phase refrigerant, which then returns to compressor 110.

[0044] As shown in FIG1 , in some embodiments of the present disclosure, the evaporation temperature of the outdoor heat exchanger 210 is Te, the exhaust pressure of the compressor 110 is Pd, the exhaust temperature is Td, the suction pressure is Ps, and the suction temperature is Ts.

[0045] For example, the compressor 110 may be a variable capacity compressor whose rotation speed is controlled by an inverter.

[0046] The four-way reversing valve 400 includes four ports: a first port C, a second port D, a third port S, and a fourth port E. The first port C is connected to the outdoor heat exchanger 120, the second port D is connected to the exhaust port 111 of the compressor 110, the third port S is connected to the gas-liquid separator 700, and the fourth port E is connected to the indoor heat exchanger 210. The four-way reversing valve 400 switches the air conditioner 1000 between cooling mode and heating mode by changing the flow direction of the refrigerant within the system pipeline.

[0047] The shutoff valve 500 includes a liquid-side shutoff valve 501 and a gas-side shutoff valve 502. The liquid-side shutoff valve 501 is located between the outdoor electronic expansion valve 310 and the indoor electronic expansion valve 320 and is configured to control the flow rate of the liquid-phase refrigerant condensed by the condenser and flowing through the pipeline. The gas-side shutoff valve 502 is located between the compressor 110 and the indoor heat exchanger 210 and is configured to control the flow rate of the gas-phase refrigerant evaporated by the evaporator and flowing through the pipeline.

[0048] The fan 600 includes an outdoor fan 601 and an indoor fan 602. The outdoor fan 601 is configured to promote heat exchange between the refrigerant flowing in the heat transfer tube of the outdoor heat exchanger 120 and the outdoor air, and the indoor fan 602 is configured to promote heat exchange between the refrigerant flowing in the heat transfer tube of the indoor heat exchanger 210 and the indoor air to assist in temperature regulation.

[0049] The gas-liquid separator 700 is configured to filter the liquid-phase refrigerant that has not been completely evaporated from the gas-phase refrigerant returned to the compressor 110 .

[0050] As shown in FIG2 , in some embodiments of the present disclosure, the air conditioner 1000 further includes a controller 91. The controller 91 is coupled to the compressor 110, the four-way valve 400, the outdoor fan 601, and the outdoor electronic expansion valve 310 in the outdoor unit 100, and is also coupled to the indoor fan 602 and the indoor electronic expansion valve 320 in the indoor unit 200. The controller 91 is configured to control the operating status of each component coupled to the controller 91.

[0051] The controller 91 includes a processor. The processor may include a central processing unit (CPU), a microprocessor (microprocessor), or an application specific integrated circuit (ASIC), and may be configured to perform the corresponding operations described in the controller 91 when the processor executes a program stored in a non-transitory computer-readable medium coupled to the controller 91.

[0052] The multi-split air conditioner 1000 includes an outdoor unit 100 and at least one indoor unit 200. For ease of description, some embodiments of the present disclosure are mainly described by taking the air conditioner 1000 including one outdoor unit 100 and two indoor units 200 as an example.

[0053] It should be noted that Figure 1 shows an application scenario in which the air conditioner 1000 includes an outdoor electronic expansion valve 310 and two indoor electronic expansion valves 320. The number of outdoor electronic expansion valves 310 and indoor electronic expansion valves 320 can be set according to demand, and this disclosure does not limit this.

[0054] In some embodiments, the outdoor unit 100 can adjust the temperature by air-cooling heat exchange, and the indoor unit 200 can adjust the temperature by evaporative heat exchange. The present disclosure does not limit the temperature adjustment form of the outdoor unit 100 or the indoor unit 200.

[0055] In some embodiments, the air conditioner 1000 further includes a remote controller, which has a function of communicating with the controller 91 using infrared rays, etc. The user can control the air conditioner 1000 through the remote controller, thereby realizing interaction between the user and the air conditioner 1000.

[0056] Affected by the complex operating environment, the refrigerant may be in a gas-liquid two-phase state when flowing through the electronic expansion valve 300. The gas-liquid two-phase refrigerant refers to a mixture of gas-phase refrigerant and liquid-phase refrigerant. Since the electronic expansion valve 300 is a throttling and pressure-reducing component, when the gas-liquid two-phase refrigerant flows through the electronic expansion valve 300, the cross-sectional area through which the refrigerant passes suddenly becomes smaller, and the liquid-phase refrigerant in the gas-liquid two-phase refrigerant passes through the expansion part of the electronic expansion valve 300 to become a gas-phase refrigerant. When the gas-phase refrigerant in the refrigerant flowing through the electronic expansion valve 300 accounts for approximately 30% to 70%, larger bubbles will be generated in the gas-phase refrigerant, and the larger bubbles will diffuse and burst, thereby generating refrigerant flow noise. It should be noted that refrigerant flow noise is usually easy to produce in heating mode.

[0057] In related art, the opening of the electronic expansion valve 300 is typically adjusted based on experience or the power of the compressor 110. However, due to the complex operating environment of air conditioners, adjusting the opening of the electronic expansion valve 300 based on experience cannot cope with frequent mode changes. When the indoor unit 200 frequently changes modes, the refrigerant flowing through the electronic expansion valve 300 produces intermittent refrigerant flow noise. This refrigerant flow noise is often high-frequency or intermittent, and users are very sensitive to high-frequency and intermittent noise.

[0058] To solve the above technical problems, some embodiments of the present disclosure provide a control method for an indoor electronic expansion valve 320. By controlling the proportion of gaseous refrigerant in the refrigerant flowing through the electronic expansion valve 300 to be lower than 30% or higher than 70%, the refrigerant flow noise is reduced.

[0059] FIG3 is a flow chart of a control method for reducing refrigerant flow noise of an indoor electronic expansion valve according to some embodiments, and FIG4 is a structural diagram of an indoor heat exchanger according to some embodiments.

[0060] As shown in FIG3 , the control method is applied to the controller 91 and includes steps S101 to S105 .

[0061] Step S101 : reading the temperature difference X between the temperature of the middle portion of the indoor heat exchanger 210 and the outlet temperature.

[0062] The temperature difference X is, for example, X=TC-TL, where TC is the temperature of the middle portion of the indoor unit heat exchanger 210, and TL is the outlet temperature.

[0063] It should be noted that the middle part of the indoor heat exchanger 210 is close to the center of the indoor heat exchanger 210 , and any one of gas-phase refrigerant, liquid-phase refrigerant or gas-liquid two-phase refrigerant can exist in the middle part of the indoor heat exchanger 210 .

[0064] In some embodiments, as shown in FIG4 , the indoor heat exchanger 210 includes an outlet pipe 211 and an inlet pipe 212. The air conditioner 1000 further includes a plurality of temperature sensors 20, such as a first temperature sensor 21 and a second temperature sensor 22. The first temperature sensor 21 is disposed near the center of the indoor heat exchanger 210 and is configured to collect the temperature TC at the center of the indoor heat exchanger 210. The second temperature sensor 22 is disposed at the outlet pipe 211 of the indoor heat exchanger 210 and is configured to collect the outlet temperature TL.

[0065] Step S102: determining the subcooling degree of the indoor electronic expansion valve 320 according to the temperature difference X.

[0066] It should be noted that the degree of under cooling (SC) refers to the difference between the temperature of the refrigerant at a certain pressure and the corresponding saturation temperature when the temperature of the refrigerant at the pressure is lower than the saturation temperature at the corresponding pressure.

[0067] FIG5 is a refrigerant pressure-enthalpy diagram according to some embodiments. As shown in FIG5 , the ordinate of the pressure-enthalpy diagram is pressure P, in Pascals (Pa), and the abscissa is specific enthalpy H. Specific enthalpy H refers to the enthalpy value of 1 kg of a substance, in kJ / kg. The degree of subcooling SC can be expressed as the difference between the temperature T6 of the refrigerant high-pressure saturated liquid (the corresponding temperature when the refrigerant is in the state corresponding to coordinate point ⑥ in FIG5 ) and the condenser outlet temperature T2 (the corresponding temperature when the refrigerant is in the state corresponding to coordinate point ② in FIG5 ): SC = T6 - T2. The refrigerant high-pressure saturated liquid can be a liquid refrigerant or a gas-liquid two-phase refrigerant.

[0068] In some embodiments, when the air conditioner 1000 operates in heating mode, the temperature TC in the middle part of the indoor heat exchanger 210 is used as the temperature T6 of the refrigerant high-pressure saturated liquid, and the detected temperature TL at the outlet pipe 211 of the indoor heat exchanger 210 is selected as the condenser outlet temperature T2. At this time, the subcooling degree of the indoor electronic expansion valve 320 can be expressed as: SC=TC-TL.

[0069] Step S103: Calculate the subcooling difference ΔSC.

[0070] The subcooling difference △SC is the difference between the subcooling SC and the subcooling setting value SC. set For example, △SC=SC-SC set .

[0071] In some embodiments, the subcooling setting value SC set Pre-set by the system, can be set according to demand. Subcooling setting value SC set Satisfaction: 0℃ <SC set <20℃, e.g., SC set (1°C to 5°C). It can be 1°C, 5°C, 10°C or 15°C.

[0072] In step S104 , the target opening degree EVI(N+1) of the indoor electronic expansion valve 320 is determined according to the subcooling degree difference ΔSC.

[0073] In some embodiments, as shown in FIG17 , the controller 91 of the air conditioner 1000 further includes a memory 92 , and the correspondence between the subcooling difference ΔSC and the opening degree of the indoor electronic expansion valve 320 can be pre-stored in the memory 92 . After the controller 91 completes the calculation of the subcooling difference ΔSC, the controller 91 retrieves the target opening degree EVI(N+1) based on the stored correspondence between the subcooling difference ΔSC and the opening degree of the indoor electronic expansion valve 320 .

[0074] Step S105 , adjusting the indoor electronic expansion valve 320 to the target opening EVI(N+1).

[0075] The controller 91 adjusts the opening of the indoor electronic expansion valve 320 according to the retrieved target opening EVI(N+1), thereby adjusting the indoor electronic expansion valve 320 to the target opening EVI(N+1). When the indoor electronic expansion valve 320 is at the target opening, the proportion of gas-phase refrigerant in the indoor electronic expansion valve 320 can basically reach less than 30% or more than 70%. This is conducive to controlling the proportion of gas-phase refrigerant and thereby reducing the refrigerant flow noise.

[0076] Figure 6 is a flow chart of a method for controlling an indoor electronic expansion valve according to some embodiments, and Figure 7 is a flow chart of another method for controlling an indoor electronic expansion valve according to some embodiments. In some embodiments, as shown in Figures 6 and 7 , before step S101 , the controller 91 also needs to perform step S100 .

[0077] Step S100: Read the status of the indoor unit 200.

[0078] In some embodiments, the indoor unit 200 includes an operating state and a non-operating state. The operating state of the indoor unit 200 refers to the state in which the indoor unit 200 is powered on and running, and the non-operating state of the indoor unit 200 refers to the state in which the indoor unit 200 is powered off or in a standby state.

[0079] In some embodiments, in response to a user starting the air conditioner 1000, the controller 91 may adjust the opening of the indoor electronic expansion valve 320 to an initial value. EVI02 is the initial value corresponding to the opening of the indoor electronic expansion valve 320 when the indoor unit 200 is in operation. When EVI(N) = EVI02, the indoor unit 200 is determined to be in operation. EVI0 is the initial value corresponding to the opening of the indoor electronic expansion valve 320 when the indoor unit 200 is not in operation. When EVI(N) = EVI0, the indoor unit 200 is determined to be not in operation.

[0080] It should be noted that EVI(N) is the current opening of the indoor electronic expansion valve 320. EVI0 and EVI02 can be set as needed. For example, EVI0 and EVI02 can be set according to the capacity of the air conditioner 1000 or the number of indoor units 200. Generally, the values ​​of EVI0 and EVI02 are positively correlated with the capacity of the air conditioner 1000 or the number of indoor units 200.

[0081] As shown in FIG. 6 , when the controller 91 determines that the indoor unit 200 is in operation, step S104 includes steps S200 to S204 .

[0082] Step S200, determine EVI(N)=EVI02.

[0083] In step S201 , it is determined whether the subcooling difference ΔSC is less than or equal to the first subcooling value G1 . If so, step S202 is executed; if not, step S203 is executed.

[0084] The first subcooling value G1 can be set according to demand, for example, G1 can be 3°C, 5°C or 6°C.

[0085] When the controller 91 determines that the subcooling difference ΔSC is greater than the first subcooling value G1, it determines that the current opening degree EVI(N) of the indoor electronic expansion valve 320 is less than the target opening degree EVI(N+1). For example, EVI(N+1)=EVI(N)+ΔEVI.

[0086] Here, EVI(N+1) is the target opening of the indoor electronic expansion valve 320, and ΔEVI is the opening variation of the indoor electronic expansion valve 320, which can be set according to needs and is not limited in this disclosure.

[0087] Step S202 , determining whether the subcooling difference ΔSC is greater than zero, if so, executing step S2021 , if not, executing step S2022 .

[0088] In order to take into account the temperature adjustment efficiency of the air conditioner 1000, the controller 91 needs to determine whether the supercooling difference ΔSC is greater than zero.

[0089] When the controller 91 determines that the supercooling difference ΔSC is greater than zero, it determines that the current opening degree EVI(N) of the indoor electronic expansion valve 320 is equal to the target opening degree EVI(N+1). For example, EVI(N+1)=EVI(N).

[0090] When the controller 91 determines that the supercooling difference ΔSC is less than zero, it determines that the current opening degree EVI(N) of the indoor electronic expansion valve 320 is greater than the target opening degree EVI(N+1). For example, EVI(N+1)=EVI(N)-ΔEVI.

[0091] Step S2021: Keep the opening of the indoor electronic expansion valve 320 unchanged.

[0092] At this time, the controller 91 ensures the temperature adjustment efficiency of the air conditioner 1000 by maintaining the opening degree of the indoor electronic expansion valve 320 constant.

[0093] Step S2022: Reduce the opening of the indoor electronic expansion valve 320.

[0094] At this time, the controller 91 reduces the opening of the indoor electronic expansion valve 320 to reduce the refrigerant flow noise.

[0095] Step S203: increasing the opening of the indoor electronic expansion valve 320.

[0096] At this time, the controller 91 reduces the refrigerant flow noise by increasing the opening of the indoor electronic expansion valve 320 .

[0097] It should be noted that after the controller 91 controls the opening of the indoor electronic expansion valve 320 to be adjusted and the indoor electronic expansion valve 320 operates stably according to the adjusted target opening EVI(N+1), the controller 91 executes step S204.

[0098] Step S204, ending this adjustment process.

[0099] As shown in FIG. 7 , when the controller 91 determines that the state of the indoor unit 200 is a non-operating state, for example, an off state or a standby state, step S104 may include steps S300 to S304 .

[0100] Step S300, determine EVI(N)=EVI0.

[0101] Step S301 , determining whether the subcooling difference ΔSC is less than or equal to the second subcooling value G2 , if so, executing step S302 , if not, executing step S303 .

[0102] The second subcooling value G2 can be set as needed. For example, G2 can be 5°C, 6°C, or 10°C. When the controller 91 determines that the subcooling difference ΔSC is less than or equal to the second subcooling value G2, it determines that the current opening degree EVI(N) of the indoor electronic expansion valve 320 is greater than the target opening degree EVI(N+1). For example, EVI(N+1) = EVI(N) - ΔEVI.

[0103] When the controller 91 determines that the subcooling difference ΔSC is greater than the second subcooling value G2, it determines that the current opening degree EVI(N) of the indoor electronic expansion valve 320 is equal to the target opening degree EVI(N+1). For example, EVI(N+1)=EVI(N).

[0104] It should be noted that, in some embodiments, since the indoor fan 602 is turned off and the indoor heat exchanger 210 cannot perform effective heat exchange when the indoor unit 200 is in a non-operating state, the second subcooling value G2 corresponding to the indoor unit 200 in a non-operating state is greater than the first subcooling value G1 corresponding to the indoor unit 200 in an operating state.

[0105] Step S302: reducing the opening of the indoor electronic expansion valve 320.

[0106] At this time, the controller 91 reduces the refrigerant flow noise by adjusting the opening of the indoor electronic expansion valve 320.

[0107] Step S303: Keep the opening of the indoor electronic expansion valve 320 unchanged.

[0108] At this time, the controller 91 ensures the temperature adjustment efficiency of the air conditioner 1000 by keeping the opening of the indoor electronic expansion valve 320 constant.

[0109] After the opening of the indoor electronic expansion valve 320 is adjusted by the controller 91 and stably operates according to the adjusted target opening EVI(N+1), step S304 is executed.

[0110] Step S304, ending this adjustment process.

[0111] In some embodiments of the present disclosure, the controller 91 may reread the temperature difference X at predetermined intervals T (e.g., 20 seconds) and promptly adjust the opening of the indoor electronic expansion valve 320 based on the temperature difference X. This can prevent refrigerant with a low degree of subcooling from flowing through the indoor electronic expansion valve 320 and generating refrigerant flow noise.

[0112] It should be noted that the shorter the predetermined time T is, the more significant the effect of the air conditioner 1000 in reducing the refrigerant flow noise is. However, a shorter predetermined time T will correspondingly increase the calculation amount of the controller 91.

[0113] Figure 8 is a flow chart of another indoor electronic expansion valve control method according to some embodiments. As shown in Figure 8 , when the operating mode of the indoor unit 200 changes, the frequency of the compressor 110 needs to be adjusted. This change in compressor 110 frequency causes a corresponding change in the refrigerant pressure within the air conditioner 1000 system, resulting in a change in the degree of subcooling (SC), which in turn affects the opening of the indoor unit's electronic expansion valve 320. Therefore, upon receiving a command to adjust the frequency of the compressor 110, the controller 91 executes steps S400-S404.

[0114] Step S400: receiving a frequency adjustment instruction of the compressor 21.

[0115] In step S401, the current operating frequency Ft of the compressor 110 is compared to see if it is less than the target frequency Fn. If so, step S402 is executed; otherwise, step S403 is executed.

[0116] When the current frequency Ft of the compressor 110 is less than the target frequency Fn, it indicates that the frequency of the compressor 110 needs to be increased to reach the target frequency Fn.

[0117] On the contrary, when the current frequency Ft of the compressor 110 is greater than the target frequency Fn, it means that the frequency of the compressor 110 needs to be reduced to reach the target frequency Fn.

[0118] Step S402: Increase the opening degree of the indoor electronic expansion valve 320 to the target opening degree EVI(N+1).

[0119] For example, EVI(N+1)=EVI(N)+ΔEVI.

[0120] In step S4021, the frequency of the compressor 110 is increased to the target frequency Fn.

[0121] Step S403: reducing the compressor frequency to the target frequency Fn.

[0122] For example, EVI(N+1)=EVI(N)-ΔEVI.

[0123] Step S4031: Reduce the opening of the indoor electronic expansion valve 320 to a target opening.

[0124] In this way, it is possible to prevent the refrigerant from generating a strong compression wave at the indoor electronic expansion valve 320 when the frequency of the compressor 110 changes, thereby preventing the indoor unit 200 from generating noise.

[0125] Step S404, ending this adjustment process.

[0126] FIG9 is a block diagram of an indoor electronic expansion valve control device according to some embodiments. As shown in FIG9 , in some embodiments, the controller 91 includes: a reading component 81 configured to read a temperature difference, or a compressor operating frequency and a target frequency, where the temperature difference is the difference between the temperature at the center of the indoor unit heat exchanger and the outlet temperature; a call component 82 configured to call the subcooling value of the indoor electronic expansion valve 320 corresponding to the temperature difference; a calculation component 83 configured to calculate the subcooling difference, where the subcooling difference is the difference between the subcooling value and a subcooling set value; a determination component 84 configured to determine a target opening of the indoor electronic expansion valve 320 based on the subcooling difference; and an adjustment component 85 configured to adjust the opening of the indoor electronic expansion valve 320 to the target opening.

[0127] FIG10 is a structural diagram of another air conditioner according to some embodiments, FIG11 is a structural diagram of a refrigerant system according to some embodiments, and FIG12 is a structural diagram of a regulating device according to some embodiments.

[0128] As shown in Figures 11 and 12, when the air conditioner 1000 is operating in heating mode, the refrigerant flows from the inlet pipe 32 of the indoor electronic expansion valve 320 to the outlet pipe 33 (in the direction indicated by the solid arrow in Figure 12). Due to the internal structure of the indoor electronic expansion valve 320, the valve needle 36 is vertical. When the refrigerant flows from the inlet pipe 32 into the indoor electronic expansion valve 320, it directly impacts the top of the valve needle 36. The valve needle 36 is subjected to the excitation force of the gaseous refrigerant, causing the valve needle 36 to vibrate and radiate high-frequency noise, which causes the valve needle 36 to vibrate and produce refrigerant flow noise. In cooling mode, the refrigerant flows in the opposite direction (in the direction indicated by the dashed arrow in Figure 12), from the outlet pipe 33 of the indoor electronic expansion valve 320 to the inlet pipe 32. In this case, the refrigerant acts perpendicularly on the side of the valve needle 36, generating less excitation force and less likely to cause the valve needle 36 to vibrate and produce refrigerant flow noise. Therefore, refrigerant flow noise is generally more likely to occur in heating mode.

[0129] In order to change the exciting force on the valve needle 36 of the indoor electronic expansion valve 320 and effectively reduce the refrigerant flow noise, as shown in Figure 10, in some embodiments, the air conditioner 1000 also includes an adjusting device 30, which is configured to reduce the impact of the gas-phase refrigerant on the valve needle 36 in the heating mode, reduce the exciting force on the valve needle 36, and thus reduce the noise of the valve needle 36.

[0130] As shown in Figures 10 and 12 , the indoor electronic expansion valve 320 includes a valve body 31, an inlet pipe 32, an outlet pipe 33, and a valve needle 36. The inlet pipe 32 communicates with the indoor heat exchanger 210, and the outlet pipe 33 communicates with the outdoor heat exchanger 120. The valve needle 36 is disposed within the valve body 31. The regulating device 30 includes a bypass pipe 34. A first end 341 of the bypass pipe 34 is connected to the inlet pipe 32 of the indoor electronic expansion valve 320, and a second end 342 of the bypass pipe 34 is connected to the valve body 31 of the indoor electronic expansion valve 320.

[0131] When the air conditioner 1000 is operating in heating mode, refrigerant flows from the inlet pipe 32 of the indoor electronic expansion valve 320 into the valve body 31 and out through the outlet pipe 33, causing the valve needle 36 to vibrate and produce refrigerant flow noise. In some embodiments of the present disclosure, the air conditioner 1000 includes a bypass pipe 34 of the regulating device 30. When the refrigerant flows through the indoor electronic expansion valve 320, a portion of the gaseous refrigerant flows through the bypass pipe 34 into the valve body 31. This helps reduce the excitation of the valve needle 36 by the gaseous refrigerant, reducing the excitation force on the valve needle 36 and thereby reducing the noise generated by the valve needle 36.

[0132] In some embodiments of the present disclosure, as shown in Figure 12, the regulating device 30 also includes a one-way valve 35, which is arranged on the bypass pipe 34 and is configured to conduct unidirectionally in the direction from the inlet pipe 32 through the bypass pipe 34 to the valve body 31.

[0133] When the air conditioner 1000 is operating in heating mode, the one-way valve 35 is open, thereby diverting the gaseous refrigerant through the bypass pipe 34 to reduce the noise of the valve needle 36. When the air conditioner 1000 is operating in cooling mode, the one-way valve 35 is closed in the direction of refrigerant flow, allowing the air conditioner 1000 to operate normally.

[0134] Some embodiments of the present disclosure further provide a control method for reducing refrigerant flow noise, which can be applied to the air conditioner 1000 shown in Figure 10. Figure 13 is a flow chart of a control method for a regulating device according to some embodiments. As shown in Figure 13, the control method is applied to the controller 91 and includes steps S10-S11.

[0135] Step S10: respond to the mode control instruction and read the operating mode carried in the mode control instruction.

[0136] In some embodiments, when a user turns on the air conditioner 1000, the user triggers a mode control command, each of which corresponds to an operating mode. Operating modes include cooling mode, heating mode, air supply mode, or dehumidification mode. The mode control command can be triggered by the user inputting it via a remote control or control panel, which then transmits the user-input start command to the controller 91 of the air conditioner 1000.

[0137] Step S11 : when the operating mode carried in the read mode control instruction is the heating mode, the one-way valve 35 is opened.

[0138] The gas phase refrigerant can be diverted through the bypass pipe 34 to reduce the noise of the valve needle 36. In this way, when the user turns on the heating mode, the one-way valve 35 is opened to reduce the refrigerant flow noise.

[0139] FIG14 is a flow chart of another method for controlling an adjusting device according to some embodiments. In some embodiments, as shown in FIG14 , step S11 may include steps S20 to S24 .

[0140] Step S20: Acquire the operating status of the indoor unit 200.

[0141] In step S21, the operating state of the indoor unit 200 is determined. When the indoor unit 200 is in the non-operating state, step S22 is executed. When the indoor unit 200 is in the operating state, steps S23 to S24 are executed.

[0142] In step S22 , the opening of the indoor electronic expansion valve 320 is set to the first opening EVI(n1), and the one-way valve 35 is opened.

[0143] In some embodiments, when the indoor unit 200 is in a non-operating state, the indoor fan 602 and the indoor heat exchanger 210 are in a closed state. However, considering the reliability of the oil return of the compressor 110, the opening of the indoor electronic expansion valve 320 also needs to be controlled to the first opening EVI (n1).

[0144] It should be noted that oil return reliability refers to the situation when the high-temperature, high-pressure gaseous refrigerant compressed by the compressor 110 is discharged from the exhaust port 111. Due to the high flow rate and high temperature of the gaseous refrigerant during discharge, some compressor oil (i.e., the lubricating oil used in the compressor) forms oil vapor and oil droplets due to the high temperature and is discharged together with the gaseous refrigerant. As the refrigerant circulates, the compressor oil is layered and deposited in the evaporator and condenser. The loss of compressor oil can affect the operation of the air conditioner 1000. In some embodiments of the present disclosure, the opening of the indoor electronic expansion valve 320 that is not turned on is set to the first opening EVI(n1) to ensure the smooth operation of the air conditioner 1000.

[0145] In step S23, the opening degree of the indoor electronic expansion valve 320 is set to the second opening degree EVI(n2).

[0146] It should be noted that the first opening degree EVI (n1) and the second opening degree EVI (n2) are preset by the system and can be set according to needs during actual application, and this disclosure does not limit this.

[0147] It should be noted that the second opening EVI (n2) is greater than the first opening EVI (n1). Since the refrigerant flow rate flowing in the system is small when the indoor unit 200 is in a non-operating state, and the refrigerant flow rate flowing in the system is large when the indoor unit 200 is in an operating state, when the indoor unit 200 changes from a non-operating state to an operating state, it is necessary to increase the opening of the indoor electronic expansion valve 320 to meet the refrigerant flow demand in the system.

[0148] Step S24: The indoor unit 200 is turned on and the first set time T is passed. set1 After that, open the one-way valve 35.

[0149] In some embodiments, when the indoor unit 200 is in operation, the indoor fan 602 and the indoor heat exchanger 210 are turned on, so that the refrigerant flowing in the heat transfer pipe of the indoor heat exchanger 210 exchanges heat with the indoor air to assist in temperature regulation. Therefore, when the indoor unit 200 is in operation and in heating mode, the proportion of gas phase refrigerant in the system is relatively small, which will not have a significant impact on the valve needle 36 of the indoor electronic expansion valve 320. Therefore, there is no need to open the one-way valve 35 in advance and wait for the first set time T set1 Then, the one-way valve 35 is opened at the same time as the compressor 110 is started.

[0150] FIG15 is a flowchart of another control method of an adjusting device according to some embodiments. In some embodiments, as shown in FIG15 , the control method is applied to a controller 91 and further includes steps S31 to S32 .

[0151] Step S31: The indoor unit 200 starts operating for a first set time T. set1 Then, the compressor 110 is started and the operating frequency of the compressor 110 is read.

[0152] In step S32 , if it is determined that the operating frequency of the compressor 110 is equal to the set frequency, the one-way valve 35 is closed.

[0153] It should be noted that, since the pressure and temperature of various parts of the system are unstable during the startup of the air conditioner 1000, it is easy to cause the indoor electronic expansion valve 320 to produce refrigerant flow noise, so the indoor electronic expansion valve 320 is first opened to balance the pressure and temperature at the inlet pipe 32 and the outlet pipe 33 of the indoor electronic expansion valve 320, and wait for the first set time T set1 After that, restarting the compressor 110 can prevent the gas-liquid two-phase refrigerant from significantly impacting the valve needle 36 of the indoor electronic expansion valve 320, thereby reducing the refrigerant flow noise. When the operating frequency of the compressor 110 is equal to the set frequency, the pressure and temperature of the entire system tend to be stable, and the refrigerant flow noise is unlikely to occur, so the one-way valve 35 can be closed.

[0154] FIG16 is a flow chart of another control method of an adjusting device according to some embodiments. In some embodiments, as shown in FIG16 , the control method is applied to a controller 91 and further includes steps S41 to S42 .

[0155] In step S41 , when the read operation mode is another mode, the opening of the indoor electronic expansion valve 320 is set to the second opening EVI(n2).

[0156] In some embodiments, other modes are modes different from the heating mode, such as a cooling mode, etc., which is not limited in the present disclosure.

[0157] Since the indoor electronic expansion valve 320 is less likely to generate refrigerant flow noise in other modes, it is only necessary to control the opening of the indoor electronic expansion valve 320 to a corresponding opening to balance the system pressure and temperature.

[0158] Step S42: After the second set time T set2 Then, the compressor 110 is started.

[0159] In other modes, the indoor electronic expansion valve 320 is first opened to balance the pressure and temperature at the inlet pipe 32 and the outlet pipe 33 of the indoor electronic expansion valve 320, and then the second set time T is waited. set2 Then, the compressor 110 is started, so that the gas phase refrigerant can be prevented from having a greater impact on the valve needle 36 of the indoor electronic expansion valve 320, thereby avoiding the generation of refrigerant flow noise.

[0160] It should be noted that the first set time T set1 and the second set time T set2 Pre-set by the system, in the actual application process, the second set time T set2 It can be set according to demand and can be equal to the first preset time T1, which is not limited in the present disclosure.

[0161] In some embodiments, the reading component 81 of the controller 91 is further configured to read the mode carried in the mode control instruction and the operating state of the indoor unit 200 . The adjusting component 85 is further configured to adjust the opening of the indoor electronic expansion valve 320 .

[0162] In some other embodiments, the reading component 81 of the controller 91 is further configured to read the operating frequency of the compressor 110 . The adjusting component 85 is further configured to adjust the operating frequency of the compressor 110 .

[0163] FIG17 is a structural diagram of a controller according to some embodiments. As shown in FIG17 , the controller 91 includes a processor 93 , a communication interface 94 , and a communication line 95 in addition to a memory 92 .

[0164] In some embodiments, the controller 91 refers to a device that can generate an operation control signal based on an instruction opcode and a timing signal, thereby instructing the air conditioner 1000 to execute the control instruction. For example, the controller 91 can be a central processing unit (CPU), a general-purpose processor, a network processor (NP), a digital signal processor (DSP), a microprocessor, a microcontroller, a programmable logic device (PLD), or any combination thereof. The controller 91 can also be other devices with processing functions, such as circuits, devices, or software modules, which are not limited in this disclosure.

[0165] In addition, the controller 91 can be used to control the operation of various components inside the air conditioner 1000, so that the various components of the air conditioner 1000 can operate to achieve various predetermined functions of the air conditioner 1000.

[0166] It should be noted that FIG17 is only an exemplary illustration of a scenario in which the controller 91 includes one processor. The above scenario does not constitute a limitation, and the number of processors can be set according to demand during actual application.

[0167] In some embodiments, the memory 92, the processor 93, and the communication interface 94 are connected via a communication line 95. The memory 92 is used to store computer program code and data. The computer program code includes instructions, and the processor 93 is used to execute the instructions stored in the memory 92. The communication interface 94 is used to connect to other external devices to receive input content, thereby realizing the controller 91 in some embodiments of the present disclosure.

[0168] The memory 92 may be a read-only memory (ROM) or other type of static storage device that can store static information and instructions, a random access memory (RAM) or other type of dynamic storage device that can store information and instructions, or an electrically erasable programmable read only memory (EEPROM), a compact disc read only memory (CD ROM) or other optical disc storage, an optical disc storage (including a compact disc, laser disc, optical disc, digital versatile disc, Blu-ray disc, etc.), a magnetic disk storage medium or other magnetic storage device, or any other medium that can be used to carry or store desired program code in the form of instructions or data structures and can be accessed by a computer, but is not limited thereto. The memory 92 may exist independently and be connected to the processor 93 via a bus. The memory 92 may also be integrated with the processor 93.

[0169] The processor 93 can be a general-purpose central processing unit (CPU), a microprocessor, an application specific integrated circuit (ASIC), or one or more integrated circuits for controlling the execution of the program of the present invention.

[0170] The communication interface 94 can be connected to components of the air conditioner 1000 such as the regulating device 30, the temperature sensor, and the compressor 110 to send signals to the components of the air conditioner 1000 or receive signals sent by the components of the air conditioner 1000.

[0171] In some embodiments of the present disclosure, the present disclosure further provides a computer program product comprising one or more instructions, which can be executed by the controller 91 of the air conditioner 1000 to implement the control method in the above embodiment.

[0172] Those skilled in the art will understand that the scope of the present invention is not limited to the above specific embodiments, and that certain elements of the embodiments may be modified and replaced without departing from the spirit of the present invention. The scope of the present invention is limited by the appended claims.

Claims

1. An air conditioner, comprising: Outdoor unit, including: a compressor configured to compress a refrigerant to drive the refrigerant to circulate in the air conditioner; an outdoor heat exchanger configured to one of liquefy or vaporize the refrigerant; At least one indoor unit connected to the outdoor unit, and each indoor unit includes: an indoor heat exchanger configured to liquefy or vaporize the refrigerant; an electronic expansion valve, connected to the indoor heat exchanger and the outdoor heat exchanger, respectively, and configured to adjust a flow rate of refrigerant flowing between the outdoor heat exchanger and the indoor heat exchanger; and The controller is configured as: Reading a temperature difference, where the temperature difference is the difference between the temperature at the middle portion of the indoor heat exchanger and the outlet temperature; determining a subcooling degree of the electronic expansion valve according to the temperature difference; Calculating a subcooling difference, where the subcooling difference is a difference between the subcooling and a subcooling set value; determining a target opening of the electronic expansion valve according to the subcooling difference; The opening of the electronic expansion valve is adjusted to a target opening to reduce the proportion of gas phase refrigerant and reduce the refrigerant flow noise.

2. The air conditioner according to claim 1, wherein Before reading the temperature difference, the controller is further configured to: Reading the status of the indoor unit; If the state of the indoor unit is running; Determining the target opening of the electronic expansion valve according to the subcooling difference includes: If the subcooling difference is greater than a first subcooling value, the current opening of the electronic expansion valve is less than the target opening of the electronic expansion valve; If the subcooling difference is between zero and the first subcooling value, the current opening of the electronic expansion valve is equal to the target opening of the electronic expansion valve; If the subcooling difference is less than zero, the current opening of the electronic expansion valve is greater than the target opening of the electronic expansion valve.

3. The air conditioner according to claim 2, wherein: If it is determined that the target opening of the electronic expansion valve is greater than the current opening of the electronic expansion valve, increasing the opening of the electronic expansion valve; If it is determined that the current opening of the electronic expansion valve is equal to the target opening of the electronic expansion valve, then the opening of the electronic expansion valve is kept unchanged; If it is determined that the current opening of the electronic expansion valve is greater than the target opening of the electronic expansion valve, the opening of the electronic expansion valve is reduced.

4. The air conditioner according to claim 2, wherein: The controller is further configured to: If the indoor unit is in non-operating state: Determining the target opening of the electronic expansion valve according to the subcooling difference further includes: If the subcooling difference is less than or equal to a second subcooling value, the current opening of the electronic expansion valve is greater than the target opening of the electronic expansion valve; If the subcooling difference is greater than the second subcooling value, the current opening of the electronic expansion valve is equal to the target opening of the electronic expansion valve.

5. The air conditioner according to claim 4, wherein If it is determined that the current opening of the electronic expansion valve is greater than the target opening of the electronic expansion valve, reducing the opening of the electronic expansion valve; If it is determined that the current opening of the electronic expansion valve is equal to the target opening of the electronic expansion valve, the opening of the electronic expansion valve is kept unchanged.

6. The air conditioner according to claim 4, wherein The second subcooling value is greater than the first subcooling value.

7. The air conditioner according to any one of claims 2 to 6, wherein: The controller is further configured to: At predetermined intervals, read the temperature difference.

8. The air conditioner according to claim 7, wherein: The controller is further configured to: In response to starting the air conditioner, the opening of the electronic expansion valve is adjusted to an initial value; the initial value is related to the capacity of the air conditioner and the number and status of the indoor units.

9. The air conditioner according to claim 7, wherein: The controller is further configured to: In response to a compressor frequency adjustment instruction, reading the compressor operating frequency and a target frequency carried in the instruction; If the operating frequency of the compressor is lower than the target frequency, the opening of the electronic expansion valve is first increased, and then the frequency of the compressor is increased.

10. The air conditioner according to claim 9, wherein The controller is further configured to: If the operating frequency of the compressor is greater than the target frequency, the frequency of the compressor is first reduced, and then the opening of the electronic expansion valve is reduced.

11. An air conditioner comprising: Outdoor unit, including: a compressor configured to compress a refrigerant to drive the refrigerant to circulate in the air conditioner; an outdoor heat exchanger configured to one of liquefy or vaporize the refrigerant; At least one indoor unit connected to the outdoor unit, and each indoor unit includes: an indoor heat exchanger configured to liquefy or vaporize the refrigerant; an electronic expansion valve connected to the indoor heat exchanger and the outdoor heat exchanger and configured to adjust a flow rate of refrigerant flowing between the outdoor heat exchanger and the indoor heat exchanger; A regulating device is connected to the electronic expansion valve and is configured to reduce the impact of the gas phase refrigerant on the electronic expansion valve. To reduce the refrigerant flow noise, the regulating device includes: a bypass pipe, disposed on one side of the inlet pipe of the electronic expansion valve, wherein a first end of the bypass pipe is connected to the inlet pipe, and a second end of the bypass pipe is connected to the valve body of the electronic expansion valve; a one-way valve disposed on the bypass pipe, and configured to conduct unidirectionally in a direction from the inlet pipe to the valve body via the bypass pipe; and The controller is configured as: responding to a mode control instruction and reading an operating mode carried by the mode control instruction; If the operating mode is the heating mode, the one-way valve is opened.

12. The air conditioner according to claim 11, wherein The opening of the one-way valve comprises: Reading the indoor unit status; If it is determined that the indoor unit is in a non-operating state, the opening degree of the electronic expansion valve is set to a first opening degree, and the one-way valve is opened.

13. The air conditioner according to claim 12, wherein The opening of the one-way valve further comprises: If it is determined that the indoor unit is in operation, setting the opening of the electronic expansion valve to a second opening, wherein the second opening is greater than the first opening; After the first set time, the one-way valve is opened.

14. The air conditioner according to claim 13, wherein After reading the indoor unit status, the controller is further configured to: After the first set time, the compressor is started.

15. The air conditioner according to claim 14, wherein After starting the compressor, the controller is further configured to: reading the frequency of the compressor; When the frequency of the compressor is equal to the set frequency, the one-way valve is closed.

16. The air conditioner according to claim 15, wherein The controller is further configured to: When the operation mode is another mode, the opening of the electronic expansion valve is set to the second opening; wherein, The other mode is a mode different from the heating mode.

17. The air conditioner according to claim 16, wherein After setting the opening of the electronic expansion valve to the second opening, the controller is further configured to: After the second set time, the compressor is started.

18. The air conditioner according to any one of claims 11 to 17, wherein: The inlet pipe is communicated with the valve body and the indoor heat exchanger respectively; the electronic expansion valve further comprises: an outlet pipe, connected to the valve body and the outdoor heat exchanger respectively; The valve needle is arranged in the valve body.

Images