Air conditioner and control method of air conditioner

Abstract

The application discloses an air conditioner and a control method of the air conditioner, wherein the air conditioner comprises a compressor, an evaporator, a condenser, a refrigerant circuit, an indoor fan and a controller; the controller is configured to: acquire the discharge pressure and the suction pressure of the compressor at the current time when the air conditioner meets the low-temperature noise reduction mode entering condition; obtain the compression ratio of the compressor at the current time according to the discharge pressure and the suction pressure; control the state of the indoor fan according to the discharge pressure at the current time; when the compression ratio at the current time is greater than or equal to a compression ratio threshold, adjust the state parameter of the compressor at the next time of the current time; and adjust the state of the indoor fan or control the frequency of the compressor according to the state parameter of the compressor at the next time. The air conditioner and the control method reduce the noise generated due to the high-pressure refrigerant impacting the pipeline, and improve the user experience.

Description

Technical Field

[0001] This invention relates to the field of air conditioning technology, and in particular to an air conditioner and a method for controlling the air conditioner. Background Technology

[0002] In related technologies, rooftop air conditioners, as a type of air conditioner, are characterized by combining the indoor and outdoor fans into one unit. Because the refrigerant piping between the indoor and outdoor fans is short and subjected to high pressure, during the air conditioner's startup, especially when heating in low-temperature environments, noise can be heard on the indoor side caused by the high-frequency vibration of the compressor in the outdoor fan and the rapid flow and pressure changes of the high-pressure refrigerant in the piping, thus affecting the user experience. Summary of the Invention

[0003] The present invention aims to at least solve one of the technical problems existing in the prior art. Therefore, one object of the present invention is to provide an air conditioner that can reduce noise generated by high-pressure refrigerant impacting the piping, thereby improving the user experience.

[0004] The second objective of this invention is to provide a control method for an air conditioner.

[0005] To achieve the above objectives, an air conditioner according to a first aspect of the present invention includes: a compressor, an evaporator, and a condenser; a refrigerant circuit that circulates refrigerant in the compressor, the evaporator, a throttling valve, and the condenser; an indoor fan for blowing air onto the evaporator; and a controller configured to: acquire the discharge pressure and suction pressure of the compressor at a current moment when the air conditioner meets the conditions for entering a low-temperature noise reduction mode; obtain the compression ratio of the compressor at the current moment based on the discharge pressure and the suction pressure; control the state of the indoor fan based on the discharge pressure at the current moment; adjust the state parameters of the compressor at the next moment when the compression ratio at the current moment is greater than or equal to a compression ratio threshold; and adjust the state of the indoor fan or control the frequency of the compressor based on the state parameters of the compressor at the next moment.

[0006] According to an embodiment of the present invention, when the air conditioner enters the low-temperature noise reduction mode, the controller can dynamically adjust the state of the indoor fan or the frequency of the compressor based on the real-time exhaust pressure and intake pressure. By adjusting the frequency of the compressor, the vibration caused by the operation of the compressor can be adjusted, thereby slowing down the flow speed and pressure changes of the refrigerant in the pipeline. By adjusting the state of the indoor fan, the anti-cold air protection of the indoor fan can be deactivated in advance. By using the evaporator of the indoor fan to dissipate heat to the room, the refrigerant pressure in the pipeline can be reduced, making the flow of refrigerant in the pipeline more stable. This effectively reduces the noise generated by the impact of high-pressure refrigerant on the pipeline and improves the user experience.

[0007] In some embodiments, the controller is further configured to: control the indoor fan to stop when the exhaust pressure at the current moment is less than a first exhaust pressure threshold; maintain the current state when the compression ratio at the current moment is less than a preset compression ratio threshold, or adjust the exhaust pressure of the compressor at the next moment to the sum of the exhaust pressure of the compressor at the current moment and a preset pressure adjustment step when the compression ratio at the current moment is greater than or equal to the preset compression ratio threshold; control the indoor fan to start and operate at a preset lower speed limit when the exhaust pressure of the compressor at the next moment is greater than or equal to the first exhaust pressure threshold, or return to the step of adjusting the exhaust pressure of the compressor when the exhaust pressure of the compressor at the next moment is less than the first exhaust pressure threshold.

[0008] In some embodiments, the controller is further configured to: control the indoor fan to operate at the preset lower speed limit when the exhaust pressure at the current moment is greater than or equal to the first exhaust pressure threshold and less than the second exhaust pressure threshold; maintain the current state when the compression ratio at the current moment is less than the preset compression ratio threshold, or adjust the exhaust pressure of the compressor at the next moment to the sum of the exhaust pressure of the compressor at the current moment and the preset pressure adjustment step size by a preset multiple when the compression ratio of the compressor at the current moment is still greater than or equal to the preset compression ratio threshold; control the indoor fan to gradually increase by a preset speed difference when the exhaust pressure of the compressor at the next moment is greater than or equal to the second exhaust pressure threshold, until the preset upper speed limit of the indoor fan is reached, wherein the second exhaust pressure threshold is greater than the first exhaust pressure threshold, or return to the step of adjusting the exhaust pressure of the compressor when the exhaust pressure of the compressor at the next moment is less than the first exhaust pressure threshold.

[0009] In some embodiments, the controller is further configured to: control the indoor fan to operate at the preset upper speed limit when the exhaust pressure at the current moment is greater than or equal to the second exhaust pressure threshold; maintain the current state when the compression ratio at the current moment is less than the preset compression ratio threshold, or adjust the frequency of the compressor at the next moment to the difference between the frequency of the compressor at the current moment and the preset frequency value when the compression ratio of the compressor at the next moment is less than or equal to the preset frequency threshold; maintain the current state and exit the low temperature noise reduction mode when the frequency of the compressor at the next moment is less than or equal to the preset frequency threshold, or return to the step of adjusting the frequency of the compressor when the frequency of the compressor at the next moment is greater than the preset frequency threshold.

[0010] In some embodiments, the controller is further configured to: determine that the air conditioner meets the low-temperature noise reduction entry condition when the air conditioner starts heating and the indoor ambient temperature is lower than a preset temperature threshold.

[0011] To achieve the above objectives, a control method for an air conditioner according to a first aspect of the present invention is used in the air conditioner described in the above embodiment. The control method includes: when the air conditioner meets the conditions for entering a low-temperature noise reduction mode, acquiring the discharge pressure and suction pressure of the air conditioner's compressor at the current moment; obtaining the compression ratio of the compressor at the current moment based on the discharge pressure and the suction pressure; controlling the state of the indoor fan of the air conditioner based on the discharge pressure at the current moment; adjusting the state parameters of the compressor at the next moment when the compression ratio at the current moment is greater than or equal to a compression ratio threshold; and adjusting the state of the indoor fan or controlling the frequency of the compressor based on the state parameters of the compressor at the next moment.

[0012] According to the control method of the air conditioner according to an embodiment of the present invention, when the air conditioner meets the conditions for entering the low temperature noise reduction mode, the controller can dynamically adjust the state of the indoor fan or the frequency of the compressor according to the real-time exhaust pressure and intake pressure. By adjusting the frequency of the compressor, the vibration caused by the operation of the compressor can be adjusted, thereby slowing down the flow speed and pressure changes of the refrigerant in the pipeline. By adjusting the state of the indoor fan, the anti-cold air protection of the indoor fan can be released in advance. By using the heat exchanger of the indoor fan to dissipate heat to the room, the refrigerant pressure in the pipeline can be reduced, making the flow of refrigerant in the pipeline more stable. This effectively reduces the noise generated by the impact of high-pressure refrigerant on the pipeline and improves the user experience.

[0013] In some embodiments, controlling the state of the indoor fan of the air conditioner according to the exhaust pressure at the current moment includes: controlling the indoor fan to be in a stopped state when the exhaust pressure at the current moment is less than a first exhaust pressure threshold; adjusting the state parameters of the compressor at the next moment when the compression ratio at the current moment is greater than or equal to the compression ratio threshold includes: adjusting the exhaust pressure of the compressor at the next moment to the sum of the exhaust pressure of the compressor at the current moment and a preset pressure adjustment step size when the compression ratio at the current moment is greater than or equal to the preset compression ratio threshold, or maintaining the current state when the compression ratio at the current moment is less than the preset compression ratio threshold; adjusting the state of the indoor fan or controlling the frequency of the compressor according to the state parameters of the compressor at the next moment includes: controlling the indoor fan to start and operate at a preset lower speed limit when the exhaust pressure of the compressor at the next moment is greater than or equal to the first exhaust pressure threshold, or returning to the step of adjusting the exhaust pressure of the compressor when the exhaust pressure of the compressor at the next moment is less than the first exhaust pressure threshold.

[0014] In some embodiments, controlling the state of the indoor fan based on the exhaust pressure at the current moment includes: when the exhaust pressure at the current moment is greater than or equal to a first exhaust pressure threshold and less than a second exhaust pressure threshold, controlling the indoor fan to operate at the preset lower speed limit; when the compression ratio at the current moment is greater than or equal to a compression ratio threshold, adjusting the state parameters of the compressor at the next moment, including: if the compression ratio of the compressor at the current moment is still greater than or equal to the preset compression ratio threshold, adjusting the exhaust pressure of the compressor at the next moment to a preset pressure that is a preset multiple of the exhaust pressure of the compressor at the current moment. Adjust the sum of the step sizes, or, if the compression ratio at the current moment is less than a preset compression ratio threshold, maintain the current state; adjust the state of the indoor fan or control the frequency of the compressor according to the state parameters of the compressor at the next moment, including: when the discharge pressure of the compressor at the next moment is greater than or equal to a second discharge pressure threshold, control the indoor fan to gradually increase by a preset speed difference until the preset upper limit of the indoor fan speed is reached, wherein the second discharge pressure threshold is greater than the first discharge pressure threshold, or, if the discharge pressure of the compressor at the next moment is less than the first discharge pressure threshold, return to the step of adjusting the discharge pressure of the compressor.

[0015] In some embodiments, controlling the state of the indoor fan according to the exhaust pressure at the current moment includes: controlling the indoor fan to operate at the preset upper speed limit when the exhaust pressure at the current moment is greater than or equal to the second exhaust pressure threshold; adjusting the state parameters of the compressor at the next moment when the compression ratio at the current moment is greater than or equal to the compression ratio threshold includes: adjusting the frequency of the compressor at the next moment to the difference between the frequency of the compressor at the current moment and the preset frequency value when the compression ratio of the compressor at the current moment is still greater than or equal to the preset compression ratio threshold, or maintaining the current state when the compression ratio at the current moment is less than the preset compression ratio threshold; adjusting the state of the indoor fan or controlling the frequency of the compressor according to the state parameters of the compressor at the next moment includes: maintaining the current state and exiting the low temperature noise reduction mode when the frequency of the compressor at the next moment is less than or equal to the preset frequency threshold, or returning to the step of adjusting the frequency of the compressor when the frequency of the compressor at the next moment is greater than the preset frequency threshold.

[0016] In some embodiments, the condition for the air conditioner to meet the low-temperature noise reduction mode entry condition includes: determining that the air conditioner meets the low-temperature noise reduction mode entry condition when the air conditioner starts heating and the indoor ambient temperature is lower than a preset temperature threshold.

[0017] Additional aspects and advantages of the invention will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. Attached Figure Description

[0018] The above and / or additional aspects and advantages of the present invention will become apparent and readily understood from the description of the embodiments taken in conjunction with the following drawings, in which:

[0019] Figure 1 This is a structural diagram of an air conditioner in related technologies;

[0020] Figure 2 This is a block diagram of an air conditioner according to an embodiment of the present invention;

[0021] Figure 3 This is a block diagram of a controller according to an embodiment of the present invention;

[0022] Figure 4 This is a flowchart of an air conditioner control method according to an embodiment of the present invention;

[0023] Figure 5 This is a flowchart illustrating the control of the indoor fan's state based on the current exhaust pressure according to an embodiment of the present invention.

[0024] Figure 6 This is a flowchart illustrating the adjustment of the compressor's state parameters for the next moment based on an embodiment of the present invention.

[0025] Figure 7 This is a flowchart illustrating the adjustment of the indoor fan's state based on the compressor's state parameters at the next moment, according to an embodiment of the present invention.

[0026] Figure 8 This is a flowchart illustrating the control of the indoor fan's state based on the current exhaust pressure according to yet another embodiment of the present invention;

[0027] Figure 9 This is a flowchart of adjusting the state parameters of the compressor at the current moment to the next moment according to yet another embodiment of the present invention;

[0028] Figure 10 This is a flowchart illustrating the adjustment of the indoor fan's state based on the compressor's state parameters at the next moment, according to yet another embodiment of the present invention.

[0029] Figure 11 This is a flowchart illustrating the control of the indoor fan's state based on the current exhaust pressure according to another embodiment of the present invention;

[0030] Figure 12 This is a flowchart illustrating the adjustment of the compressor's state parameters for the next moment based on another embodiment of the present invention;

[0031] Figure 13 This is a flowchart illustrating the adjustment of the compressor frequency based on the compressor's state parameters at the next moment, according to another embodiment of the present invention.

[0032] Figure 14 This is an overall flowchart of an air conditioner control method according to an embodiment of the present invention.

[0033] Figure label:

[0034] Related technologies:

[0035] Air conditioner 100'; compressor module 1'; evaporator module 2'; condenser module 3'.

[0036] This invention:

[0037] Air conditioner 100;

[0038] 1. Compressor; 2. Evaporator; 3. Condenser; 4. Expansion valve; 5. Refrigerant circuit; 6. Indoor fan; 7. Controller;

[0039] Processor 71; Memory 72. Detailed Implementation

[0040] The embodiments of the present invention are described in detail below. The embodiments described with reference to the accompanying drawings are exemplary. The embodiments of the present invention are described in detail below.

[0041] Figure 1 This is a structural diagram of an air conditioner in related technologies, such as... Figure 1 As shown, the rooftop unit, as a type of air conditioner 100', is characterized by combining the indoor and outdoor fans into one unit. Because the refrigerant piping between the indoor and outdoor fans is short and subjected to high pressure, during the start-up process of the air conditioner 100', especially when heating in low-temperature environments, vibrations caused by the high-frequency operation of the compressor module 1' in the outdoor fan and noise from the high-pressure refrigerant impacting the piping in the evaporator module 2' can be heard on the indoor side, thus affecting the user experience.

[0042] To address the aforementioned issues, this invention proposes an air conditioner that can reduce noise generated by high-pressure refrigerant impacting the piping, thereby improving the user experience.

[0043] Figure 2 This is a block diagram of an air conditioner according to an embodiment of the present invention. (Refer to the following...) Figure 2 An air conditioner according to an embodiment of the present invention is described.

[0044] like Figure 2 As shown, the air conditioner 100 may include a compressor 1. In some embodiments, the compressor 1 may be a core component of the air conditioner 100, responsible for compressing the refrigerant, increasing its pressure and temperature, thereby driving the refrigerant to circulate in the refrigerant circuit 5.

[0045] In some embodiments, compressor 1 may be a different type of compressor 1, such as a reciprocating compressor, a rotary compressor, a screw compressor, or a scroll compressor.

[0046] Among them, reciprocating compressors compress refrigerant through the reciprocating motion of a piston within a cylinder; rotary compressors compress refrigerant through rotating blades or a rolling piston; screw compressors compress refrigerant through the meshing motion of two screws; and scroll compressors compress refrigerant through the relative motion of two scroll plates. All of these compressors 1 can be designed as variable frequency compressors, allowing the operating speed of compressor 1 to be controlled by adjusting its operating frequency, thereby adjusting the refrigerant flow and pressure.

[0047] In some embodiments, the specific type of compressor 1 may be selected based on the specific requirements and application scenarios of the air conditioner 100, and no specific restrictions are imposed here.

[0048] like Figure 2As shown, the air conditioner 100 may include an evaporator 2. In some embodiments, the evaporator 2 is a heat exchange device in the air conditioner 100, and its main function is to absorb heat from the surrounding environment during the process of the refrigerant absorbing heat and evaporating, thereby achieving a cooling effect.

[0049] In some embodiments, the evaporator 2 may be a different type of evaporator 2, such as a finned evaporator, a plate evaporator, or a shell-and-tube evaporator.

[0050] Among them, finned evaporators can be composed of fins and coils to increase the heat exchange area and improve the heat exchange efficiency; plate evaporators can be composed of multiple layers of metal plates, and heat exchange is achieved through the flow of refrigerant between the plates; shell and tube evaporators can achieve heat exchange through the flow of refrigerant inside the tubes and the flow of air inside the shell.

[0051] In some embodiments, the specific type of evaporator 2 can be selected based on the specific requirements and application scenarios of the air conditioner 100, and no specific restrictions are imposed here.

[0052] like Figure 2 As shown, the air conditioner 100 may include a condenser 3. In some embodiments, the condenser 3 may be another heat exchange device in the air conditioner 100, whose main function is to cool and condense the high-pressure, high-temperature refrigerant compressed by the compressor 1 into a liquid state, thereby releasing heat to achieve a heating effect. The condenser 3 may also be a finned condenser, a plate condenser, or a shell-and-tube condenser, etc. The specific type of condenser 3 can be determined according to the specific requirements and application scenarios of the air conditioner 100, and no specific restrictions are imposed here.

[0053] like Figure 2 As shown, the air conditioner 100 may include a throttle valve 4. In some embodiments, the throttle valve 4 may be a device for controlling the refrigerant flow rate, which achieves flow rate regulation by changing the cross-sectional area of ​​the fluid passage. The throttle valve 4 may take various forms, including but not limited to an electric expansion valve, a thermostatic expansion valve, and a manual expansion valve.

[0054] In some embodiments, the specific type of throttle valve 4 can be selected according to the specific requirements and application scenarios of the air conditioner 100, and no specific restrictions are imposed here.

[0055] like Figure 2 As shown, the air conditioner 100 may include a refrigerant circuit 5. In some embodiments, the refrigerant circuit 5 may be a closed piping system in the air conditioner 100 for circulating refrigerant, in which the refrigerant circulates in the compressor 1, evaporator 2, expansion valve 4 and condenser 3.

[0056] Specifically, compressor 1 draws in low-pressure, low-temperature gaseous refrigerant and then compresses it into high-pressure, high-temperature gaseous refrigerant through compression. Then, the high-pressure, high-temperature gaseous refrigerant enters condenser 3, where it comes into contact with external air or water to dissipate heat and condense into high-pressure, high-temperature liquid refrigerant.

[0057] Furthermore, the liquid refrigerant in condenser 3 enters evaporator 2 through throttling valve 4, where it comes into contact with indoor air, absorbs indoor heat, and evaporates into low-pressure, low-temperature gaseous refrigerant. Finally, the gaseous refrigerant is drawn back into compressor 1, repeating the above process.

[0058] like Figure 2 As shown, the air conditioner 100 may include an indoor fan 6. In some embodiments, the indoor fan 6 may be a device in the air conditioner 100 for blowing air onto the evaporator 2. The indoor fan 6 may include components such as a motor, impeller, air duct, and filter, as well as circuitry and control devices for controlling its operation. The main function of the indoor fan 6 is to achieve the cooling or heating effect of the air conditioner 100 by circulating indoor air, and to ensure indoor air circulation and comfort.

[0059] like Figure 2 As shown, the air conditioner 100 may include a controller 7. In some embodiments, the controller 7 may be a device for controlling the operating status and parameters of various components of the air conditioner 100.

[0060] Furthermore, such as Figure 3 As shown, the controller 7 may include a processor 71 and a memory 72.

[0061] The processor 71 executes control algorithms and logic, processes data provided by sensors, and generates corresponding control signals to adjust the operating status of various components in the air conditioner 100. The memory 72 stores program code, control parameters, and historical data to support the normal operation and data recording of the controller 7. The combination of these components enables the controller 7 to achieve precise control and intelligent management of the air conditioner 100.

[0062] In some embodiments, the controller 7 is configured to: when the air conditioner 100 meets the conditions for entering the low-temperature noise reduction mode, acquire the discharge pressure and suction pressure of the compressor 1 at the current moment, obtain the compression ratio of the compressor 1 at the current moment based on the discharge pressure and suction pressure, control the state of the indoor fan 6 based on the discharge pressure at the current moment, and adjust the state parameters of the compressor 1 for the next moment when the compression ratio at the current moment is greater than or equal to the compression ratio threshold. The controller 7 also adjusts the state of the indoor fan 6 or controls the frequency of the compressor 1 based on the state parameters of the compressor 1 for the next moment.

[0063] Specifically, the low-temperature noise reduction mode is an operating mode of the air conditioner 100, the purpose of which is to reduce the noise generated by refrigerant impacting the pipes in low-temperature environments. The current discharge pressure and suction pressure of the compressor 1 can be obtained in real time through a pressure sensor or other sensors connected to the compressor 1.

[0064] Furthermore, assuming the current time is t, the discharge pressure of compressor 1 at time t is Pd[t], the intake pressure of compressor 1 at time t is Ps[t], and the compression ratio of compressor 1 at time t is S[t]. The compression ratio of compressor 1 at time t can be obtained from the discharge and intake pressures, using the following formula:

[0065] S[t]=(Pd[t]+0.1) / (Ps[t]+0.1)

[0066] The 0.1 in the formula serves to prevent division by zero during calculation. In the compression ratio calculation formula, the denominator Ps[t] may be zero, especially in the initial stage or under certain special circumstances. To prevent calculation errors or system anomalies caused by a zero denominator, a small constant, such as 0.1, can be added to the denominator. This way, even if Ps[t] is zero, the denominator will not be equal to zero, thus avoiding errors in division operations. Therefore, 0.1 here plays a protective role, ensuring the accuracy of the calculation and the stability of the system.

[0067] Furthermore, the status of the indoor fan 6 can be controlled based on the current exhaust pressure, such as starting, stopping, or adjusting the speed. Therefore, by adjusting the starting timing of the indoor fan 6, the cold air protection of the indoor fan 6 can be released in advance, and the evaporator 2 of the indoor fan 6 can be used to dissipate heat into the room, which can reduce the refrigerant pressure in the pipeline and make the refrigerant flow in the pipeline more stable.

[0068] Furthermore, when the compression ratio at the current moment is greater than or equal to the compression ratio threshold, the state parameters of compressor 1 at the next moment are adjusted. The compression ratio threshold can be a preset compression ratio value used to determine whether the current operating state of compressor 1 needs adjustment. This threshold can be set according to system design requirements, environmental conditions, and user needs, and is not specifically limited here.

[0069] Furthermore, the controller 7 adjusts the state of the indoor fan 6 or controls the frequency of the compressor 1 based on the state parameters of the compressor 1 at the next moment. By adjusting the frequency of the compressor 1, the controller 7 can reduce the compression ratio, slow down the flow speed and pressure changes of the refrigerant in the pipeline, thereby reducing the noise generated by the impact of high-pressure refrigerant on the pipeline.

[0070] According to an embodiment of the present invention, when the air conditioner 100 enters the low-temperature noise reduction mode, the controller 7 can dynamically adjust the state of the indoor fan 6 or the frequency of the compressor 1 according to the real-time exhaust pressure and intake pressure. By adjusting the frequency of the compressor 1, the vibration caused by the operation of the compressor 1 can be adjusted, thereby slowing down the flow speed and pressure changes of the refrigerant in the pipeline. By adjusting the state of the indoor fan 6, the anti-cold air protection of the indoor fan 6 can be deactivated in advance. By using the evaporator 2 of the indoor fan 6 to dissipate heat to the room, the refrigerant pressure in the pipeline can be reduced, making the flow of the refrigerant in the pipeline more stable. This effectively reduces the noise generated by the impact of high-pressure refrigerant on the pipeline and improves the user experience.

[0071] In some embodiments, the controller 7 is further configured to stop the indoor fan 6 when the current exhaust pressure is less than a first exhaust pressure threshold. This indicates that the current exhaust pressure of the compressor 1 is low. To prevent cold air from being blown out, the indoor fan 6 remains stopped until the exhaust pressure of the compressor 1 reaches the preset threshold, ensuring that unheated air is not blown into the room. The first exhaust pressure threshold can be a preset pressure value, which can be set according to system design requirements, environmental conditions, and user needs, and is not specifically limited here.

[0072] In some embodiments, when the compression ratio at the current moment is less than a preset compression ratio threshold, the current state is maintained. This indicates that the discharge pressure and suction pressure of compressor 1 at the current moment are in a relatively balanced and stable state. At this time, the refrigerant flow rate in the pipeline is slower, and noise and vibration are relatively low. Maintaining the current state helps to prevent cold air from being blown out, thereby improving the user experience.

[0073] In some embodiments, when the compression ratio at the current moment is greater than or equal to a preset compression ratio threshold, the discharge pressure of compressor 1 at the next moment is adjusted to the sum of the discharge pressure of compressor 1 at the current moment and a preset pressure adjustment step.

[0074] The preset pressure adjustment step size can be a fixed amount that adjusts the discharge pressure of compressor 1 within each adjustment cycle. This amount can be a specific value, such as 0.01 MPa, indicating an increase or decrease of 0.01 MPa each time the pressure is adjusted. The preset pressure adjustment step size can be set according to factors such as system characteristics, design parameters, and experimental data, and is not specifically limited here.

[0075] Therefore, adjusting the discharge pressure of compressor 1 at the next moment to the sum of the discharge pressure of compressor 1 at the current moment and the preset pressure adjustment step size is a gradually increasing adjustment to smoothly increase the discharge pressure of compressor 1.

[0076] In some embodiments, when the discharge pressure of compressor 1 at the next moment is greater than or equal to a first discharge pressure threshold, the indoor fan 6 is controlled to start and operate at a preset lower speed limit. The preset lower speed limit can be the minimum operating speed (expressed in revolutions per minute, RPM) set by controller 7 for indoor fan 6 under specific operating conditions. The preset lower speed limit can be set according to fan performance curves, refrigerant pressure and flow characteristics, cold air protection requirements, etc., and is not specifically limited here.

[0077] Specifically, in heating mode, the air conditioner 100 has a cold air protection mechanism to prevent the indoor fan 6 from blowing out cold air when the compressor 1 has just started or when the outdoor temperature is low, thus affecting user comfort. When the exhaust pressure reaches the first exhaust pressure threshold, it indicates that the compressor 1 has started to work effectively and the refrigerant in the compressor 1 has reached a sufficient temperature, so hot air can be blown out by the indoor fan 6, thereby deactivating the cold air protection of the indoor fan 6.

[0078] Furthermore, by controlling the indoor fan 6 to operate at a preset lower speed limit, the indoor fan 6 can be started slowly, avoiding sudden large airflows that could cause discomfort to the indoor environment. This also gradually increases the heat release from the evaporator 2, improving system stability. When the indoor fan 6 starts and operates, the evaporator 2 begins effective heat exchange, and heat is transferred to the room, thereby reducing the refrigerant pressure in the evaporator 2. This heat exchange process helps to smoothly reduce the pressure inside the air conditioner 100, reducing fluctuations and shocks in refrigerant flow.

[0079] Therefore, by gradually increasing the discharge pressure of compressor 1 so that the discharge pressure of compressor 1 at the next moment is greater than or equal to the first discharge pressure threshold, the indoor fan 6 can be started in advance and run at a low speed. This accelerates the heat exchange efficiency of evaporator 2, transfers the heat of the refrigerant to the indoor air, and reduces the pressure of the refrigerant. This helps to slow down the flow rate and pressure changes of the refrigerant in the pipeline, thereby reducing the noise generated by the impact of high-pressure refrigerant on the pipeline.

[0080] In some embodiments, when the discharge pressure of compressor 1 at the next moment is less than the first discharge pressure threshold, the step of adjusting the discharge pressure of compressor 1 is returned to continuously increase the discharge pressure until the condition that the discharge pressure of compressor 1 at the next moment is greater than or equal to the first discharge pressure threshold is met.

[0081] In some embodiments, the controller 7 is further configured to: control the indoor fan 6 to operate at a preset lower speed limit when the exhaust pressure at the current moment is greater than or equal to a first exhaust pressure threshold and less than a second exhaust pressure threshold. This is because although the exhaust pressure at the current moment has met the conditions for starting the indoor fan 6, the exhaust pressure has not yet exceeded the set higher second exhaust pressure threshold.

[0082] Therefore, the indoor fan 6 needs to be controlled to operate at a preset lower speed limit to avoid discomfort caused by high speed. Then, by starting the indoor fan 6, heat exchange can begin, thereby gradually reducing the refrigerant pressure in the pipes, preventing high-pressure refrigerant from impacting the pipes, reducing noise, and improving the user experience.

[0083] In some embodiments, if the compression ratio at the current moment is less than a preset compression ratio threshold, the current state is maintained. Alternatively, if the compression ratio of compressor 1 at the current moment is still greater than or equal to the preset compression ratio threshold, the discharge pressure of compressor 1 at the next moment is adjusted to the sum of the discharge pressure of compressor 1 at the current moment and a preset pressure adjustment step size of a preset multiple. The purpose of this is to further accelerate the increase in the discharge pressure of compressor 1 to meet the conditions for subsequent adjustment of the indoor fan 6 speed, thereby adjusting the operating state of the system and achieving more efficient heat exchange and noise reduction effects.

[0084] In some embodiments, the preset multiplier can be selected as 1x, 2x, 3x, 5x or other multipliers. The preset multiplier can be set according to the specific system design requirements, environmental conditions, experimental tests and simulation analysis, and no specific restrictions are imposed here.

[0085] In some embodiments, when the discharge pressure of compressor 1 at the next moment is greater than or equal to a second discharge pressure threshold, the indoor fan 6 is controlled to gradually increase by a preset speed difference until it reaches a preset upper limit of the indoor fan 6 speed, wherein the second discharge pressure threshold is greater than the first discharge pressure threshold. The purpose of this step is that when the discharge pressure of compressor 1 reaches a high value, gradually increasing the speed of indoor fan 6 can enhance the heat exchange effect, help to reduce the pressure of refrigerant in the pipeline more quickly, further reduce the noise generated by high-pressure refrigerant impacting the pipeline, and improve the operational stability and user comfort of air conditioner 100.

[0086] In some embodiments, the preset speed difference can be the increase in speed each time the indoor fan speed is adjusted. The preset speed difference can be 5r, 8r, 10r, 12r, 15r, 20r or other speed values. The preset speed difference can be set based on a comprehensive consideration of the system's operating characteristics, heat exchange efficiency and noise control, and through experimental verification, and is not specifically limited here.

[0087] In some embodiments, when the discharge pressure of compressor 1 at the next moment is less than the second discharge pressure threshold, the step of adjusting the discharge pressure of compressor 1 is returned, that is, the discharge pressure of compressor 1 at the next moment is adjusted to the sum of the discharge pressure of compressor 1 at the current moment and the preset pressure adjustment step size of the preset multiple, so as to continuously increase the discharge pressure until the condition that the discharge pressure of compressor 1 at the next moment is greater than or equal to the second discharge pressure threshold is met.

[0088] In some embodiments, the controller 7 is further configured to: control the indoor fan 6 to operate at a preset upper speed limit when the current exhaust pressure is greater than or equal to a second exhaust pressure threshold. This indicates that when the current exhaust pressure is greater than or equal to the second exhaust pressure threshold, the exhaust pressure of the compressor 1 is already relatively high. At this time, controlling the indoor fan 6 to operate at the preset upper speed limit (maximum speed) can better enhance the heat exchange effect and reduce the pressure of the refrigerant in the pipeline more quickly, thereby reducing the noise generated by the refrigerant impacting the pipeline.

[0089] However, if it is necessary to further reduce the compression ratio of compressor 1, this can be achieved by reducing the frequency of compressor 1. Specifically, if the compression ratio at the current moment is less than a preset compression ratio threshold, the current state is maintained; or, if the compression ratio of compressor 1 at the current moment is greater than or equal to the preset compression ratio threshold, the frequency of compressor 1 at the next moment is adjusted to the difference between the frequency of compressor 1 at the current moment and the preset frequency value.

[0090] When the compression ratio of compressor 1 at the current moment is greater than or equal to the preset compression ratio threshold, it indicates that the compression ratio of compressor 1 is high and the load on compressor 1 is high. This may lead to excessively high pressure in the pipeline, causing the refrigerant to flow rapidly in the pipeline and generating noise. To reduce the compression ratio, the load on compressor 1 can be reduced by decreasing the frequency of compressor 1, thereby slowing down the refrigerant flow rate and pressure changes, and thus reducing noise.

[0091] In some embodiments, the preset frequency value can be a fixed step size when adjusting the frequency of compressor 1, which determines the magnitude of frequency change during each adjustment. The preset frequency value can be 2Hz, 3Hz, 5Hz, 8Hz, 10Hz, or other frequency values. The preset frequency value can be set according to the design specifications and performance curves of compressor 1, the operating requirements of the system, the actual application scenario, and experimental data, and is not specifically limited here.

[0092] In some embodiments, when the frequency of compressor 1 at the next moment is less than or equal to a preset frequency threshold, the current state is maintained and the low-temperature noise reduction mode is exited. This means that when the pressure in the pipeline drops to a certain level, the noise is also greatly reduced. At this point, the low-temperature noise reduction mode is no longer needed, and the system will exit this mode and operate in normal mode.

[0093] In some embodiments, if the frequency of compressor 1 at the next moment is greater than a preset frequency threshold, the process returns to the step of adjusting the frequency of compressor 1 and continues to gradually reduce the frequency. Each adjustment reduces the frequency by a preset frequency value until the frequency drops to or below the preset frequency threshold. This ensures that by gradually reducing the frequency of compressor 1, the compression ratio is continuously reduced, thereby gradually reducing the pressure and noise within the pipeline.

[0094] In some embodiments, the controller 7 is further configured to: determine that the air conditioner 100 meets the low-temperature noise reduction entry condition when the air conditioner 100 starts heating and the indoor ambient temperature is lower than a preset temperature threshold. The preset temperature threshold can be an indoor ambient temperature value pre-set in the air conditioner 100, used to determine whether to enter a specific operating mode (such as a low-temperature noise reduction mode). The preset temperature threshold can be set according to user comfort, environmental conditions, usage scenarios, equipment performance, etc., and is not specifically limited here. By reasonably setting the preset temperature threshold, the air conditioner 100 can be ensured to operate efficiently and with low noise in different environments, improving the user experience.

[0095] The following is for reference. Figure 4 A control method for an air conditioner according to an embodiment of the present invention is described, the method being used in the air conditioner described in the above embodiment.

[0096] Figure 4 This is a flowchart of an air conditioner control method according to an embodiment of the present invention, such as... Figure 4 As shown, the control method for the air conditioner includes at least steps S1-S5, as detailed below:

[0097] S1: When the air conditioner meets the conditions for entering the low-temperature noise reduction mode, obtain the discharge pressure and suction pressure of the air conditioner's compressor at the current moment.

[0098] In some embodiments, the low-temperature noise reduction mode is an operating mode of the air conditioner, the purpose of which is to reduce the noise generated by refrigerant impacting the piping in low-temperature environments. The compressor's discharge and suction pressures can be obtained in real time using pressure sensors or other sensors connected to the compressor. For example, pressure sensors can be installed at the compressor's discharge and suction ports respectively, collecting pressure data every second and transmitting the data to the controller.

[0099] In some embodiments, obtaining the current discharge pressure and suction pressure of the air conditioner's compressor is to monitor the compressor's operating status in real time and provide data for subsequent adjustments.

[0100] S2, obtains the compressor's compression ratio at the current moment based on the exhaust pressure and intake pressure.

[0101] Specifically, assuming the current time is t, the compressor's discharge pressure at time t is Pd[t], the compressor's intake pressure at time t is Ps[t], and the compressor's compression ratio at time t is S[t]. The compressor's compression ratio at time t can be obtained from the discharge and intake pressures, using the following formula:

[0102] S[t]=(Pd[t]+0.1) / (Ps[t]+0.1)

[0103] Therefore, the compression ratio, which is the ratio of discharge pressure to suction pressure, is an important parameter for measuring compressor load. The controller calculates the current compression ratio to determine whether the air conditioner's operating status needs adjustment.

[0104] Furthermore, the 0.1 in the formula is used to ensure that division by zero is avoided during the calculation. In the formula for calculating the compression ratio, the denominator Ps[t] may be zero, especially in the initial stage or under certain special circumstances. To prevent calculation errors or system anomalies caused by a zero denominator, a small constant, such as 0.1, can be added to the denominator. This way, even if Ps[t] is zero, the denominator will not be equal to zero, thus avoiding errors in division operations.

[0105] S3 controls the status of the indoor fan of the air conditioner based on the current exhaust pressure.

[0106] Specifically, the controller can control the status of the indoor fan based on the current exhaust pressure, such as starting, stopping, or adjusting the speed. If the current exhaust pressure is low, the controller can keep the indoor fan stopped. If the current exhaust pressure is high, the controller can start the indoor fan and achieve heat exchange and pressure reduction by using a low speed or gradually increasing the speed.

[0107] Therefore, by adjusting the start-up timing of the indoor fan, the cold air protection of the indoor fan can be released in advance, and the evaporator of the indoor fan can be used to dissipate heat into the room, which can reduce the refrigerant pressure in the pipeline and make the refrigerant flow in the pipeline more stable.

[0108] S4, when the compression ratio at the current moment is greater than or equal to the compression ratio threshold, adjust the state parameters of the compressor at the next moment.

[0109] Specifically, if the compression ratio at the current moment is greater than or equal to the compression ratio threshold, it indicates that the compressor load at the current moment is relatively large. The controller can adjust the compressor state parameters at the next moment to reduce the compression ratio, thereby slowing down the flow rate and pressure changes of the refrigerant in the pipeline.

[0110] In some embodiments, the compression ratio threshold can be a preset compression ratio value used to determine whether the current operating state of the compressor needs adjustment. This threshold can be set according to factors such as system design requirements, environmental conditions, and user needs, and is not specifically limited here.

[0111] S5 adjusts the status of the indoor fan or controls the frequency of the compressor based on the compressor's status parameters at the next moment.

[0112] Specifically, the controller adjusts the indoor fan's status (e.g., whether to increase its speed) or controls the compressor's frequency based on the compressor's status parameters at the next moment. Adjusting the indoor fan's status can further accelerate the evaporator's heat dissipation into the room, helping to reduce refrigerant pressure in the pipes more quickly. Adjusting the compressor's frequency allows the controller to reduce the compression ratio, slowing down refrigerant flow and pressure changes in the pipes, thereby reducing noise caused by high-pressure refrigerant impacting the pipes.

[0113] According to the control method of the air conditioner according to an embodiment of the present invention, when the air conditioner meets the conditions for entering the low temperature noise reduction mode, the controller can dynamically adjust the state of the indoor fan or the frequency of the compressor according to the real-time exhaust pressure and intake pressure. By adjusting the frequency of the compressor, the vibration caused by the operation of the compressor can be adjusted, thereby slowing down the flow speed and pressure changes of the refrigerant in the pipeline. By adjusting the state of the indoor fan, the anti-cold air protection of the indoor fan can be released in advance. By using the heat exchanger of the indoor fan to dissipate heat to the room, the refrigerant pressure in the pipeline can be reduced, making the flow of refrigerant in the pipeline more stable. This effectively reduces the noise generated by the impact of high-pressure refrigerant on the pipeline and improves the user experience.

[0114] In some embodiments, controlling the state of the indoor fan of the air conditioner based on the current exhaust pressure includes: controlling the indoor fan to be in a stopped state when the current exhaust pressure is less than a first exhaust pressure threshold. This indicates that the compressor's exhaust pressure is low at the current moment, and in order to prevent cold air from being blown out, the indoor fan remains stopped until the compressor's exhaust pressure reaches a preset threshold, ensuring that unheated air is not blown into the room.

[0115] In some embodiments, the first exhaust pressure threshold can be a preset pressure value, which can be set according to factors such as system design requirements, environmental conditions and user needs, and is not specifically limited here.

[0116] For example, assuming the current time is time t, the compressor's discharge pressure at time t is Pd[t]. The first discharge pressure threshold can be set to Pd1. When the controller detects that Pd[t] < Pd1, it controls the indoor fan to stop to prevent cold air from blowing out.

[0117] Figure 5 This is a flowchart illustrating the control of the indoor fan's state based on the current exhaust pressure according to an embodiment of the present invention, such as... Figure 5 As shown, controlling the status of the indoor fan based on the current exhaust pressure includes at least steps S10-S13, as detailed below:

[0118] S10, the air conditioner enters low temperature and noise reduction mode.

[0119] S11: The air conditioner starts running for 5 minutes. The system is running stably by default. The compressor's discharge pressure and suction pressure are obtained at the current moment.

[0120] S12, determine that the exhaust pressure at the current moment is less than the first exhaust pressure threshold.

[0121] S13, control the indoor fan to be in a stopped state.

[0122] In some embodiments, when the compression ratio at the current moment is greater than or equal to a compression ratio threshold, the state parameters of the compressor at the next moment are adjusted, including: when the compression ratio at the current moment is greater than or equal to a preset compression ratio threshold, adjusting the discharge pressure of the compressor at the next moment to the sum of the discharge pressure of the compressor at the current moment and a preset pressure adjustment step size.

[0123] The preset pressure adjustment step size can be a fixed amount that adjusts the compressor discharge pressure within each adjustment cycle. This amount can be a specific value, such as 0.01 MPa, indicating an increase or decrease of 0.01 MPa each time the pressure is adjusted. The preset pressure adjustment step size can be set based on factors such as system characteristics, design parameters, and experimental data, and is not specifically limited here.

[0124] Therefore, adjusting the compressor's discharge pressure at the next moment to the sum of the compressor's discharge pressure at the current moment and the preset pressure adjustment step size is a gradually increasing adjustment to smoothly increase the compressor's discharge pressure.

[0125] In some embodiments, when the compression ratio at the current moment is less than a preset compression ratio threshold, the current state is maintained. This indicates that the compressor's discharge pressure and suction pressure are in a relatively balanced and stable state at the current moment. At this time, the refrigerant flow rate in the pipeline is slower, and noise and vibration are relatively lower. Maintaining the current shutdown state helps prevent cold air from being blown out, thereby improving the user experience.

[0126] For example, assuming the current time is t, the compression ratio at time t is S[t]. The preset compression ratio threshold can be set to S1. When the controller calculates that S[t] ≥ S1, the compressor's discharge pressure Pd[t+1] at the next time moment is adjusted to the sum of the compressor's discharge pressure Pd[t] at the current time moment and the preset pressure adjustment step size (e.g., 0.01 MPa), i.e., Pd[t+1] = Pd[t] + 0.01. When the controller calculates that S[t] < S1, the fan remains stopped.

[0127] Figure 6 This is a flowchart illustrating the adjustment of the compressor's state parameters from the current moment to the next moment according to an embodiment of the present invention, as shown below. Figure 6As shown, adjusting the compressor's state parameters for the next time step from the current time step includes at least steps S20-S23, as detailed below:

[0128] S20 obtains the compressor's compression ratio at the current moment based on the exhaust pressure and intake pressure.

[0129] S21. Determine whether the compression ratio at the current moment is greater than or equal to the preset compression ratio threshold. If yes, proceed to step S22; otherwise, proceed to step S23.

[0130] S22, adjust the compressor's discharge pressure at the next moment to the sum of the compressor's discharge pressure at the current moment and the preset pressure adjustment step size.

[0131] S23, keep the fan in a stopped state.

[0132] In some embodiments, adjusting the state of the indoor fan or controlling the frequency of the compressor according to the state parameters of the compressor at the next moment includes: when the discharge pressure of the compressor at the next moment is greater than or equal to a first discharge pressure threshold, controlling the indoor fan to start and operate at a preset lower speed limit.

[0133] Specifically, in heating mode, the air conditioner has a cold air protection mechanism to prevent the indoor fan from blowing out cold air when the compressor has just started or when the outdoor temperature is low, thus affecting user comfort. When the exhaust pressure reaches the first exhaust pressure threshold, it indicates that the compressor has started to work effectively and the refrigerant inside the compressor has reached a sufficient temperature, allowing the indoor fan to blow out hot air and thus deactivating the cold air protection mechanism.

[0134] Furthermore, by controlling the indoor fan to operate at a preset lower speed limit, the indoor fan can be started slowly, avoiding sudden large airflows that could cause discomfort in the indoor environment. This also gradually increases the heat release from the evaporator, improving system stability. When the indoor fan starts and runs, the evaporator begins effective heat exchange, transferring heat to the room and reducing the refrigerant pressure in the evaporator. This heat exchange process helps to smoothly reduce the pressure inside the air conditioner, reducing fluctuations and impacts in refrigerant flow, thereby reducing noise caused by high-pressure refrigerant impacting the pipes.

[0135] In some embodiments, if the compressor's discharge pressure is less than a first discharge pressure threshold at the next moment, the step of adjusting the compressor's discharge pressure is returned to continuously increase the discharge pressure until the condition that the compressor's discharge pressure at the next moment is greater than or equal to the first discharge pressure threshold is met.

[0136] For example, assuming the current time is t, the compression ratio at time t is S[t]. The preset compression ratio threshold can be set to S1. When the controller calculates that S[t] ≥ S1, the compressor's discharge pressure Pd[t+1] at the next time moment is adjusted to the sum of the compressor's discharge pressure Pd[t] at the current time moment and the preset pressure adjustment step size (e.g., 0.01 MPa), i.e., Pd[t+1] = Pd[t] + 0.01. When the controller calculates that S[t] < S1, the fan remains stopped.

[0137] Furthermore, the compressor's discharge pressure Pd[t+1] at the next moment is compared with the first discharge pressure threshold Pd1. If Pd[t+1] ≥ Pd1, the indoor fan is started and operates at the preset lower speed limit. If Pd[t+1] < Pd1, the compressor's discharge pressure at the next moment is adjusted to the sum of the compressor's discharge pressure at the current moment and the preset pressure adjustment step size, so as to continuously increase the discharge pressure until the condition that the compressor's discharge pressure at the next moment is greater than or equal to the first discharge pressure threshold is met.

[0138] Figure 7 This is a flowchart illustrating the adjustment of the indoor fan's state based on the compressor's state parameters at the next moment, according to an embodiment of the present invention. Figure 7 As shown, the process of adjusting the state of the indoor fan according to the compressor's state parameters at the next moment includes at least steps S30-S39, as follows:

[0139] S30, the air conditioner enters low temperature and noise reduction mode.

[0140] S31: The air conditioner has been running for 5 minutes since startup. The system is running stably by default. The compressor's discharge pressure and suction pressure are obtained at the current moment.

[0141] S32, determine that the exhaust pressure at the current moment is less than the first exhaust pressure threshold.

[0142] S33 controls the indoor fan to be stopped.

[0143] S34 obtains the compressor's compression ratio at the current moment based on the exhaust pressure and intake pressure.

[0144] S35, determine whether the compression ratio at the current moment is greater than or equal to the preset compression ratio threshold. If yes, proceed to step S36; otherwise, proceed to step S37.

[0145] S36, adjust the compressor's discharge pressure at the next moment to the sum of the compressor's discharge pressure at the current moment and the preset pressure adjustment step size.

[0146] S37, keep the fan in a stopped state.

[0147] S38. Determine whether the compressor's discharge pressure at the next moment is greater than or equal to the first discharge pressure threshold. If yes, proceed to step S39; otherwise, return to step S36.

[0148] S39 controls the indoor fan to start and operate at the preset lower speed limit.

[0149] In summary, by gradually increasing the compressor's discharge pressure so that the next moment's discharge pressure is greater than or equal to the first discharge pressure threshold, the indoor fan can be started earlier and run at low speed. This accelerates the evaporator's heat exchange efficiency, transferring heat from the refrigerant to the indoor air and reducing the refrigerant pressure. This helps to slow down the refrigerant's flow rate and pressure changes in the pipes, thereby reducing noise caused by high-pressure refrigerant impacting the pipes.

[0150] In some embodiments, controlling the state of the indoor fan based on the current exhaust pressure includes: when the current exhaust pressure is greater than or equal to a first exhaust pressure threshold and less than a second exhaust pressure threshold, controlling the indoor fan to operate at a preset lower speed limit. This is because although the current exhaust pressure has met the conditions for starting the indoor fan, the exhaust pressure has not yet exceeded the set higher second exhaust pressure threshold.

[0151] Therefore, it is necessary to control the indoor fan to operate at a preset lower speed limit to avoid discomfort caused by high speed. Then, by starting the indoor fan, heat exchange can begin, thereby gradually reducing the refrigerant pressure in the pipes, preventing high-pressure refrigerant from impacting the pipes, reducing noise, and improving the user experience.

[0152] For example, assuming the current time is time t, the compressor's discharge pressure at time t is Pd[t]. The first discharge pressure threshold can be set to Pd1, and the second discharge pressure threshold can be set to Pd2. When the controller detects that Pd1≤Pd[t]≤Pd2, it controls the indoor fan to operate at the preset lower speed limit.

[0153] Figure 8 This is a flowchart illustrating the control of the indoor fan's state based on the current exhaust pressure according to another embodiment of the present invention, such as... Figure 8 As shown, controlling the status of the indoor fan based on the current exhaust pressure includes at least steps S40-S43, as detailed below:

[0154] S40, the air conditioner enters low temperature and noise reduction mode.

[0155] S41, the air conditioner starts running for 5 minutes, the system is running stably by default, and the compressor's discharge pressure and suction pressure are obtained at the current moment.

[0156] S42, determine that the exhaust pressure at the current moment is greater than or equal to the first exhaust pressure threshold and less than the second exhaust pressure threshold.

[0157] S43 controls the indoor fan to operate at the preset lower speed limit.

[0158] In some embodiments, when the compression ratio at the current moment is greater than or equal to a compression ratio threshold, the state parameters of the compressor at the next moment are adjusted, including: if the compression ratio of the compressor at the current moment is greater than or equal to a preset compression ratio threshold, the discharge pressure of the compressor at the next moment is adjusted to the sum of the discharge pressure of the compressor at the current moment and a preset pressure adjustment step size of a preset multiple. The purpose of this is to further accelerate the increase in the compressor's discharge pressure to meet the conditions for subsequent adjustment of the indoor fan speed, thereby adjusting the system's operating state and achieving more efficient heat exchange and noise reduction.

[0159] In some embodiments, when the compression ratio at the current moment is less than a preset compression ratio threshold, the current state is maintained, that is, the indoor fan is controlled to operate at a preset lower speed limit. This is because the compression ratio at the current moment is low, and the system does not need to make additional adjustments or increase the load. Therefore, maintaining the current state can reduce the pressure in the pipeline, reduce noise, and at the same time avoid the indoor fan outputting a large air volume, which would affect the user's experience.

[0160] For example, assuming the current time is t, the compression ratio at time t is S[t]. The preset compression ratio threshold can be set to S1. When the controller calculates that S[t] ≥ S1, the compressor's discharge pressure Pd[t+1] at the next time moment is adjusted to the sum of the compressor's discharge pressure Pd[t] at the current time and a preset pressure adjustment step size (such as 2 × 0.01 MPa), i.e., Pd[t+1] = Pd[t] + 2 × 0.02. When the controller calculates that S[t] < S1, the indoor fan is kept running at the preset lower speed limit.

[0161] Figure 9 This is a flowchart illustrating the adjustment of the compressor's state parameters for the next moment based on another embodiment of the present invention, as shown below. Figure 9 As shown, adjusting the compressor's state parameters for the next moment from the current moment includes at least steps S50-S53, as detailed below:

[0162] S50 obtains the compressor's compression ratio at the current moment based on the exhaust pressure and intake pressure.

[0163] S51, determine whether the compression ratio at the current moment is greater than or equal to the preset compression ratio threshold. If yes, proceed to step S52; otherwise, proceed to step S53.

[0164] S52, adjust the compressor's discharge pressure at the next moment to the sum of the compressor's discharge pressure at the current moment and a preset pressure adjustment step size of a preset multiple.

[0165] S53, keep the indoor fan running at the preset lower speed limit.

[0166] In some embodiments, adjusting the state of the indoor fan or controlling the frequency of the compressor according to the state parameters of the compressor at the next moment includes: when the discharge pressure of the compressor at the next moment is greater than or equal to a second discharge pressure threshold, controlling the indoor fan to gradually increase by a preset speed difference until the preset upper limit of the indoor fan speed is reached, wherein the second discharge pressure threshold is greater than the first discharge pressure threshold.

[0167] Specifically, when the compressor's discharge pressure reaches a high value, gradually increasing the indoor fan speed can enhance the heat exchange effect, help reduce the pressure of the refrigerant in the pipes more quickly, further reduce the noise generated by the high-pressure refrigerant impacting the pipes, and improve the operating stability and user comfort of the air conditioner.

[0168] In some embodiments, when the compressor's discharge pressure at the next moment is less than the second discharge pressure threshold, the step of adjusting the compressor's discharge pressure is returned. That is, the compressor's discharge pressure at the next moment is adjusted to the sum of the compressor's discharge pressure at the current moment and a preset pressure adjustment step size of a preset multiple, so as to continuously increase the discharge pressure until the condition that the compressor's discharge pressure at the next moment is greater than or equal to the second discharge pressure threshold is met.

[0169] For example, assuming the current time is t, the compression ratio at time t is S[t]. The preset compression ratio threshold can be set to S1. When the controller calculates that S[t] ≥ S1, the compressor's discharge pressure Pd[t+1] at the next time moment is adjusted to the sum of the compressor's discharge pressure Pd[t] at the current time and a preset pressure adjustment step size (such as 2 × 0.01 MPa), i.e., Pd[t+1] = Pd[t] + 2 × 0.02. When the controller calculates that S[t] < S1, the indoor fan is kept running at the preset lower speed limit.

[0170] Furthermore, the compressor's discharge pressure Pd[t+1] at the next moment is compared with the second discharge pressure threshold Pd2. If Pd[t+1] ≥ Pd2, the indoor fan is controlled to gradually increase by a preset speed difference until the preset upper limit of the indoor fan speed is reached. If Pd[t+1] < Pd1, the compressor's discharge pressure at the next moment is adjusted to the sum of the compressor's discharge pressure at the current moment and a preset pressure adjustment step size of a preset multiple, so as to continuously increase the discharge pressure until the condition that the compressor's discharge pressure at the next moment is greater than or equal to the second discharge pressure threshold is met.

[0171] Figure 10 This is a flowchart illustrating the adjustment of the indoor fan's state based on the compressor's state parameters at the next moment, according to yet another embodiment of the present invention. Figure 10 As shown, the process of adjusting the state of the indoor fan according to the compressor's state parameters at the next moment includes at least steps S60-S69, as detailed below:

[0172] S60, the air conditioner enters low temperature and noise reduction mode.

[0173] S61, the air conditioner starts running for 5 minutes, the system is running stably by default, and the compressor's discharge pressure and suction pressure are obtained at the current moment.

[0174] S62, determine that the exhaust pressure at the current moment is greater than or equal to the first exhaust pressure threshold and less than the second exhaust pressure threshold.

[0175] S63 controls the indoor fan to operate at a preset lower speed limit.

[0176] S64 obtains the compressor's compression ratio at the current moment based on the exhaust pressure and intake pressure.

[0177] S65, determine whether the compression ratio at the current moment is greater than or equal to the preset compression ratio threshold. If yes, proceed to step S66; otherwise, proceed to step S67.

[0178] S66, adjust the compressor's discharge pressure at the next moment to the sum of the compressor's discharge pressure at the current moment and a preset pressure adjustment step size of a preset multiple.

[0179] S67, keep the indoor fan running at the preset lower speed limit.

[0180] S68. Determine whether the compressor's discharge pressure at the next moment is greater than or equal to the second discharge pressure threshold. If yes, proceed to step S69; otherwise, return to step S66.

[0181] S69 controls the indoor fan to gradually increase by a preset speed difference until it reaches the preset upper limit of the indoor fan speed.

[0182] In summary, by gradually increasing the compressor's discharge pressure so that the compressor's discharge pressure at the next moment is greater than or equal to the second discharge pressure threshold, the indoor fan speed can be increased, the heat exchange of the indoor fan can be increased, the compression ratio can be further reduced, and the flow speed and pressure changes of the refrigerant in the pipeline can be slowed down, thereby reducing the noise generated by the refrigerant impacting the pipeline.

[0183] In some embodiments, controlling the state of the indoor fan based on the exhaust pressure at the current moment includes: when the exhaust pressure at the current moment is greater than or equal to a second exhaust pressure threshold, controlling the indoor fan to operate at a preset upper speed limit.

[0184] If the current exhaust pressure is greater than or equal to the second exhaust pressure threshold, it indicates that the compressor is under high load. In order to ensure effective heat exchange, the indoor fan can be controlled to operate at the preset speed limit to quickly reduce the refrigerant pressure in the pipeline, thereby reducing the noise caused by the refrigerant impacting the pipeline.

[0185] For example, assuming the current time is time t, the compressor's discharge pressure at time t is Pd[t]. The second discharge pressure threshold can be set to Pd2. When the controller detects that Pd[t]≥Pd2, it controls the indoor fan to operate at the preset speed limit to increase the heat exchange of the indoor fan and reduce the refrigerant pressure in the pipeline.

[0186] Figure 11 This is a flowchart illustrating the control of the indoor fan's state based on the current exhaust pressure according to another embodiment of the present invention, such as... Figure 11 As shown, controlling the status of the indoor fan based on the current exhaust pressure includes at least steps S70-S73, as detailed below:

[0187] S70, the air conditioner enters low temperature and noise reduction mode.

[0188] S71: After the air conditioner has been running for 5 minutes, the system is running stably by default. The system obtains the compressor's discharge pressure and suction pressure at the current moment.

[0189] S72, determine that the exhaust pressure at the current moment is greater than or equal to the second exhaust pressure threshold.

[0190] S73 controls the indoor fan to operate at a preset speed limit.

[0191] In some embodiments, when the compression ratio at the current moment is greater than or equal to a compression ratio threshold, the state parameters of the compressor at the next moment are adjusted, including: if the compression ratio of the compressor at the current moment is greater than or equal to a preset compression ratio threshold, the frequency of the compressor at the next moment is adjusted to the difference between the frequency of the compressor at the current moment and a preset frequency value.

[0192] If the current compression ratio is greater than or equal to the compression ratio threshold, it indicates that the compressor is under high load, and the compressor frequency may need to be reduced to lower the load. By reducing the compressor frequency, the compression ratio and load can be decreased, slowing down the refrigerant flow rate and pressure changes, thereby reducing noise.

[0193] In some embodiments, when the compression ratio at the current moment is less than a preset compression ratio threshold, the current state is maintained, that is, the indoor fan is controlled to operate at a preset upper speed limit. By gradually increasing the compressor's discharge pressure, the compressor's discharge pressure at the next moment gradually meets or exceeds a second discharge pressure threshold.

[0194] For example, assuming the current time is t, the compression ratio at time t is S[t], the frequency at time t is Q[t], the preset compression ratio threshold can be set to S1, and the preset frequency value can be set to 2 Hz. When the controller calculates that S[t] ≥ S1, the compressor frequency Q[t+1] at the next time moment is adjusted to the difference between the compressor frequency Q[t] at the current time moment and the preset frequency value 2 Hz, i.e., Q[t+1] = Q[t] - 2. When the controller calculates that S[t] < S1, the indoor fan is kept running at the preset upper limit of speed.

[0195] Figure 12 This is a flowchart illustrating the adjustment of the compressor's state parameters from the current moment to the next moment according to another embodiment of the present invention, as shown below. Figure 12 As shown, adjusting the compressor's state parameters for the next moment from the current moment includes at least steps S80-S83, as detailed below:

[0196] S80 obtains the compressor's compression ratio at the current moment based on the exhaust pressure and intake pressure.

[0197] S81, determine whether the compression ratio at the current moment is greater than or equal to the preset compression ratio threshold. If yes, proceed to step S82; otherwise, proceed to step S83.

[0198] S82, adjust the compressor frequency at the next moment to the difference between the compressor frequency at the current moment and the preset frequency value.

[0199] S83, keep the indoor fan running at the preset speed limit.

[0200] In some embodiments, adjusting the state of the indoor fan or controlling the frequency of the compressor based on the compressor's state parameters at the next moment includes: maintaining the current state and exiting the low-temperature noise reduction mode when the compressor's frequency at the next moment is less than or equal to a preset frequency threshold.

[0201] If the compressor frequency at the next moment is less than or equal to the preset frequency threshold, it indicates that the compressor load has decreased to a certain range, the pressure in the pipeline has decreased to a certain level, and the noise problem has been alleviated. At this point, the low-temperature noise reduction mode can be exited, and normal operation can be resumed.

[0202] In some embodiments, if the compressor frequency exceeds a preset frequency threshold at the next moment, the process returns to adjusting the compressor frequency and continues to gradually reduce the frequency. Each adjustment reduces the frequency by a preset frequency value until the frequency drops to or below the preset frequency threshold. This ensures that by gradually reducing the compressor frequency, the compression ratio is continuously reduced, thereby gradually reducing the pressure and noise within the pipeline.

[0203] For example, assuming the current time is t, the compression ratio at time t is S[t], the frequency at time t is Q[t], the preset compression ratio threshold can be set to S1, the preset frequency value can be set to 2 Hz, and the preset frequency threshold is Q1. When the controller calculates that S[t] ≥ S1, the compressor frequency Q[t+1] at the next time moment is adjusted to the difference between the compressor frequency Q[t] at the current time moment and the preset frequency value 2 Hz, i.e., Q[t+1] = Q[t] - 2. When the controller calculates that S[t] < S1, the indoor fan is kept running at the preset upper limit of speed.

[0204] Furthermore, the compressor frequency Q[t+1] at the next moment is compared with the preset frequency threshold Q1. If Q[t+1] < Q1, the current state is maintained, and the low-temperature noise reduction mode is exited. If Q[t+1] ≥ Q1, the compressor frequency at the next moment is adjusted to the difference between the compressor frequency at the current moment and the preset frequency value, so as to gradually reduce the compressor frequency and continuously reduce the compression ratio until the condition that the compressor frequency at the next moment is less than or equal to the preset frequency threshold is met.

[0205] Figure 13 This is a flowchart illustrating the adjustment of the compressor frequency based on the compressor's state parameters at the next moment, according to another embodiment of the present invention. Figure 13 As shown, the process of adjusting the compressor frequency based on the compressor's state parameters at the next moment includes at least steps S90-S99, as detailed below:

[0206] S90, the air conditioner enters low temperature and noise reduction mode.

[0207] S91: After the air conditioner has been running for 5 minutes, the system is running stably by default. The system obtains the compressor's discharge pressure and suction pressure at the current moment.

[0208] S92, determine that the exhaust pressure at the current moment is greater than or equal to the second exhaust pressure threshold.

[0209] S93 controls the indoor fan to operate at a preset speed limit.

[0210] S94 obtains the compressor's compression ratio at the current moment based on the exhaust pressure and intake pressure.

[0211] S95, determine whether the compression ratio at the current moment is greater than or equal to the preset compression ratio threshold. If yes, proceed to step S96; otherwise, proceed to step S97.

[0212] S96, adjust the compressor frequency at the next moment to the difference between the compressor frequency at the current moment and the preset frequency value.

[0213] S97, keep the indoor fan running at the preset speed limit.

[0214] S98, determine whether the compressor frequency at the next moment is less than or equal to the preset frequency threshold. If yes, proceed to step S99; otherwise, return to step S96.

[0215] S99, maintain the current state and exit the low-temperature noise reduction mode.

[0216] In general, by gradually reducing the compressor frequency until it reaches or falls below a preset frequency threshold, the compression ratio can be further reduced, thereby gradually reducing the pressure and noise within the pipeline.

[0217] In some embodiments, when the current suction pressure is greater than the suction pressure threshold, the indoor fan can maintain high-speed operation. In this case, the compressor frequency can be reduced to lower the compression ratio, thereby reducing noise.

[0218] In some embodiments, the condition for the air conditioner to meet the low-temperature noise reduction mode entry condition includes: determining that the air conditioner meets the low-temperature noise reduction mode entry condition when the air conditioner starts heating and the indoor ambient temperature is lower than a preset temperature threshold.

[0219] The indoor ambient temperature can be monitored in real time by a temperature sensor installed in the air conditioner. Users can set preset temperature thresholds through the air conditioner's control panel or a related mobile application and adjust them according to their needs. In this way, users can decide when to activate the low-temperature noise reduction mode based on their personal comfort preferences and environmental conditions.

[0220] Therefore, when the air conditioner is simultaneously in heating mode and the indoor ambient temperature is below the preset temperature threshold, the conditions for entering the low-temperature noise reduction mode are met. This means that the air conditioner can activate the low-temperature noise reduction mode to reduce system noise and adjust the operating status of the indoor fan and compressor according to specific control strategies, thereby improving user comfort.

[0221] Figure 14 This is an overall flowchart of an air conditioner control method according to an embodiment of the present invention, as follows: Figure 14 As shown, the overall flow of the air conditioner control method includes at least steps S100-S129, as detailed below:

[0222] S100, Air conditioner heating mode activated.

[0223] S101, determine whether the indoor ambient temperature is lower than the preset temperature threshold. If it is lower, proceed to step S103; if it is not lower, proceed to step S102.

[0224] S102, the air conditioner has entered normal operating mode.

[0225] S103, the air conditioner has entered the low temperature and noise reduction mode.

[0226] S104: The air conditioner has been running for 5 minutes. The system is running stably by default. The compressor's discharge pressure and suction pressure are obtained at the current moment.

[0227] S105, compare the current exhaust pressure with the first exhaust pressure threshold and the second exhaust pressure threshold.

[0228] S106, determine that the exhaust pressure at the current moment is less than the first exhaust pressure threshold.

[0229] S107, the indoor fan is controlled to be stopped.

[0230] S108 obtains the compressor's compression ratio at the current moment based on the exhaust pressure and intake pressure.

[0231] S109, determine whether the compression ratio at the current moment is greater than or equal to the preset compression ratio threshold. If yes, proceed to step S110; otherwise, proceed to step S111.

[0232] S110, adjust the compressor's discharge pressure at the next moment to the sum of the compressor's discharge pressure at the current moment and the preset pressure adjustment step size.

[0233] S111, keep the fan in a stopped state.

[0234] S112, determine whether the compressor's discharge pressure at the next moment is greater than or equal to the first discharge pressure threshold. If yes, proceed to step S113; otherwise, return to step S110.

[0235] S113 controls the indoor fan to start and operate at the preset lower speed limit.

[0236] S114, determine that the exhaust pressure at the current moment is greater than or equal to the first exhaust pressure threshold and less than the second exhaust pressure threshold.

[0237] The S115 controls the indoor fan to operate at the preset lower speed limit.

[0238] S116, obtains the compressor's compression ratio at the current moment based on the exhaust pressure and intake pressure.

[0239] S117. Determine whether the compression ratio at the current moment is greater than or equal to the preset compression ratio threshold. If yes, proceed to step S118; otherwise, proceed to step S119.

[0240] S118, adjust the compressor's discharge pressure at the next moment to the sum of the compressor's discharge pressure at the current moment and a preset pressure adjustment step size of a preset multiple.

[0241] S119, keep the indoor fan running at the preset lower speed limit.

[0242] S120, determine whether the compressor's discharge pressure at the next moment is greater than or equal to the second discharge pressure threshold. If yes, proceed to step S121; otherwise, return to step S118.

[0243] S121 controls the indoor fan to gradually increase by a preset speed difference until it reaches the preset upper limit of the indoor fan speed.

[0244] S122, determine that the exhaust pressure at the current moment is greater than or equal to the second exhaust pressure threshold.

[0245] S123 controls the indoor fan to operate at the preset speed limit.

[0246] S124 obtains the compressor's compression ratio at the current moment based on the exhaust pressure and intake pressure.

[0247] S125, determine whether the compression ratio at the current moment is greater than or equal to the preset compression ratio threshold. If yes, proceed to step S126; otherwise, proceed to step S127.

[0248] S126, adjust the compressor frequency at the next moment to the difference between the compressor frequency at the current moment and the preset frequency value.

[0249] S127, keep the indoor fan running at the preset speed limit.

[0250] S128. Determine whether the compressor frequency at the next moment is less than or equal to the preset frequency threshold. If yes, proceed to step S129; otherwise, return to step S126.

[0251] S129, maintain the current state and exit the low-temperature noise reduction mode.

[0252] In summary, when the air conditioner meets the conditions for entering the low-temperature noise reduction mode, the controller can dynamically adjust the status of the indoor fan or the frequency of the compressor based on the real-time exhaust pressure and intake pressure. By adjusting the compressor frequency, the vibration caused by the compressor's operation can be reduced, thereby slowing down the flow speed and pressure changes of the refrigerant in the pipeline. By adjusting the status of the indoor fan, the anti-cold air protection of the indoor fan can be deactivated in advance, and the heat exchanger of the indoor fan can be used to dissipate heat into the room, which can reduce the refrigerant pressure in the pipeline and make the refrigerant flow in the pipeline more stable. This effectively reduces the noise generated by the impact of high-pressure refrigerant on the pipeline and improves the user experience.

[0253] In the description of this specification, references to terms such as "one embodiment," "some embodiments," "illustrative embodiment," "example," "specific example," or "some examples," etc., refer to specific features, structures, materials, or characteristics described in connection with that embodiment or example, which are included in at least one embodiment or example of the present invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example.

[0254] Although embodiments of the invention have been shown and described, those skilled in the art will understand that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the claims and their equivalents.

Claims

1. An air conditioner, characterized in that, include: Compressor, evaporator, and condenser; A refrigerant circuit that circulates refrigerant in the compressor, the evaporator, the expansion valve, and the condenser; An indoor fan is used to blow air onto the evaporator; The controller is configured to, when the air conditioner meets the conditions for entering the low-temperature noise reduction mode, Obtain the discharge pressure and intake pressure of the compressor at the current moment; The compression ratio of the compressor at the current moment is obtained based on the exhaust pressure and the intake pressure. The state of the indoor fan is controlled according to the exhaust pressure at the current moment; When the compression ratio at the current moment is greater than or equal to a preset compression ratio threshold, the state parameters of the compressor at the next moment are adjusted. Adjust the state of the indoor fan or control the frequency of the compressor based on the state parameters of the compressor at the next moment; The condition for the air conditioner to meet the low-temperature noise reduction mode entry condition includes: when the air conditioner starts heating and the indoor ambient temperature is lower than a preset temperature threshold, it is determined that the air conditioner meets the low-temperature noise reduction mode entry condition.

2. The air conditioner according to claim 1, characterized in that, The controller is also configured to: When the exhaust pressure at the current moment is less than the first exhaust pressure threshold, the indoor fan is controlled to be stopped. When the compression ratio at the current moment is less than the preset compression ratio threshold, the current state is maintained; or, when the compression ratio at the current moment is greater than or equal to the preset compression ratio threshold, the discharge pressure of the compressor at the next moment is adjusted to the sum of the discharge pressure of the compressor at the current moment and the preset pressure adjustment step size. When the compressor's discharge pressure is greater than or equal to the first discharge pressure threshold at the next moment, the indoor fan is controlled to start and operate at a preset lower speed limit; or, when the compressor's discharge pressure is less than the first discharge pressure threshold at the next moment, the process returns to adjusting the compressor's discharge pressure.

3. The air conditioner according to claim 2, characterized in that, The controller is also configured to: When the exhaust pressure at the current moment is greater than or equal to the first exhaust pressure threshold and less than the second exhaust pressure threshold, the indoor fan is controlled to operate at the preset lower speed limit. When the compression ratio at the current moment is less than the preset compression ratio threshold, the current state is maintained; or, when the compression ratio of the compressor at the current moment is still greater than or equal to the preset compression ratio threshold, the discharge pressure of the compressor at the next moment is adjusted to the sum of the discharge pressure of the compressor at the current moment and the preset pressure adjustment step size by a preset multiple. When the compressor's discharge pressure is greater than or equal to the second discharge pressure threshold at the next moment, the indoor fan is controlled to gradually increase by a preset speed difference until the preset upper limit of the indoor fan's speed is reached, wherein the second discharge pressure threshold is greater than the first discharge pressure threshold. Alternatively, when the compressor's discharge pressure is less than the second discharge pressure threshold at the next moment, the process returns to adjusting the compressor's discharge pressure.

4. The air conditioner according to claim 3, characterized in that, The controller is also configured to: If the exhaust pressure at the current moment is greater than or equal to the second exhaust pressure threshold, the indoor fan is controlled to operate at the preset upper speed limit. When the compression ratio at the current moment is less than the preset compression ratio threshold, the current state is maintained; or, when the compression ratio of the compressor at the current moment is still greater than or equal to the preset compression ratio threshold, the frequency of the compressor at the next moment is adjusted to the difference between the frequency of the compressor at the current moment and the preset frequency value. If the compressor frequency at the next moment is less than or equal to a preset frequency threshold, maintain the current state and exit the low-temperature noise reduction mode; or, if the compressor frequency at the next moment is greater than the preset frequency threshold, return to the step of adjusting the compressor frequency.

5. A control method for an air conditioner, characterized in that, For an air conditioner according to any one of claims 1-4, the control method comprises: When the air conditioner meets the conditions for entering the low-temperature noise reduction mode, the discharge pressure and suction pressure of the air conditioner's compressor at the current moment are obtained. The conditions for the air conditioner to meet the conditions for entering the low-temperature noise reduction mode include: when the air conditioner starts heating and the indoor ambient temperature is lower than a preset temperature threshold, it is determined that the air conditioner meets the conditions for entering the low-temperature noise reduction mode. The compression ratio of the compressor at the current moment is obtained based on the exhaust pressure and the intake pressure. The state of the indoor fan of the air conditioner is controlled according to the exhaust pressure at the current moment; When the compression ratio at the current moment is greater than or equal to the preset compression ratio threshold, the state parameters of the compressor at the next moment are adjusted. Adjust the state of the indoor fan or control the frequency of the compressor based on the state parameters of the compressor at the next moment.

6. The control method for an air conditioner according to claim 5, characterized in that, Controlling the state of the indoor fan of the air conditioner according to the exhaust pressure at the current moment includes: controlling the indoor fan to be in a stopped state when the exhaust pressure at the current moment is less than a first exhaust pressure threshold. When the compression ratio at the current moment is greater than or equal to the preset compression ratio threshold, the state parameters of the compressor at the next moment are adjusted, including: when the compression ratio at the current moment is greater than or equal to the preset compression ratio threshold, adjusting the discharge pressure of the compressor at the next moment to the sum of the discharge pressure of the compressor at the current moment and the preset pressure adjustment step size; or, when the compression ratio at the current moment is less than the preset compression ratio threshold, maintaining the current state. Adjusting the state of the indoor fan or controlling the frequency of the compressor based on the state parameters of the compressor at the next moment includes: controlling the indoor fan to start and operate at a preset lower speed limit when the discharge pressure of the compressor at the next moment is greater than or equal to the first discharge pressure threshold; or returning to the step of adjusting the discharge pressure of the compressor when the discharge pressure of the compressor at the next moment is less than the first discharge pressure threshold.

7. The control method for an air conditioner according to claim 6, characterized in that, Controlling the state of the indoor fan according to the exhaust pressure at the current moment includes: when the exhaust pressure at the current moment is greater than or equal to the first exhaust pressure threshold and less than the second exhaust pressure threshold, controlling the indoor fan to operate at the preset speed lower limit value; When the compression ratio at the current moment is greater than or equal to the preset compression ratio threshold, the state parameters of the compressor at the next moment are adjusted, including: if the compression ratio of the compressor at the current moment is still greater than or equal to the preset compression ratio threshold, the discharge pressure of the compressor at the next moment is adjusted to the sum of the discharge pressure of the compressor at the current moment and the preset pressure adjustment step size of a preset multiple; or, when the compression ratio at the current moment is less than the preset compression ratio threshold, the current state is maintained. Adjusting the state of the indoor fan or controlling the frequency of the compressor based on the state parameters of the compressor at the next moment includes: when the discharge pressure of the compressor at the next moment is greater than or equal to a second discharge pressure threshold, controlling the indoor fan to gradually increase by a preset speed difference until the preset upper limit of the indoor fan speed is reached, wherein the second discharge pressure threshold is greater than the first discharge pressure threshold; or, when the discharge pressure of the compressor at the next moment is less than the first discharge pressure threshold, returning to the step of adjusting the discharge pressure of the compressor.

8. The control method for an air conditioner according to claim 7, characterized in that, Controlling the state of the indoor fan according to the exhaust pressure at the current moment includes: when the exhaust pressure at the current moment is greater than or equal to the second exhaust pressure threshold, controlling the indoor fan to operate at the preset upper speed limit value; When the compression ratio at the current moment is greater than or equal to the preset compression ratio threshold, the state parameters of the compressor at the next moment are adjusted, including: if the compression ratio of the compressor at the current moment is still greater than or equal to the preset compression ratio threshold, the frequency of the compressor at the next moment is adjusted to the difference between the frequency of the compressor at the current moment and the preset frequency value; or, when the compression ratio at the current moment is less than the preset compression ratio threshold, the current state is maintained. Adjusting the state of the indoor fan or controlling the frequency of the compressor based on the state parameters of the compressor at the next moment includes: maintaining the current state and exiting the low-temperature noise reduction mode when the frequency of the compressor at the next moment is less than or equal to a preset frequency threshold, or returning to the step of adjusting the frequency of the compressor when the frequency of the compressor at the next moment is greater than the preset frequency threshold.

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