Air conditioner and control method thereof

Abstract

The present application relates to air conditioning technical field, specifically provide a kind of air conditioner and its control method, to solve the problem that the control of existing air conditioner to air temperature is inaccurate and difficult to meet user demand.To this end, the control method of the present application includes: obtaining the air temperature of air conditioner;Based on air temperature and set temperature, control valve device to preset variation amplitude carry out valve opening degree adjustment;Every interval first preset time length, obtain the absolute value of the difference between air temperature and set temperature of air conditioner;If last absolute value in preset number is greater than preset value, based on the change trend of multiple and continuous absolute value, control air conditioner operating parameter change.The present application can accurately control air temperature, meet user demand, and according to the change trend of the absolute value of the difference between multiple air temperature and set temperature to control the change of air conditioner operating parameter, so that air temperature reaches set temperature more quickly.

Description

Technical Field

[0001] This invention relates to the field of air conditioning technology, specifically providing an air conditioner and its control method. Background Technology

[0002] With economic development and improved living standards, air conditioning has become ubiquitous and an indispensable part of modern life. However, as air conditioning technology continues to advance, consumers' expectations for air conditioners are also rising, no longer satisfied with just basic cooling or heating functions.

[0003] Traditional air conditioning systems are relatively simple in design, operating based on the user-set target ambient temperature. Once the control coil temperature reaches the target ambient temperature, the compressor stops working. However, at this point, the air conditioner's outlet temperature may differ from the user's actual set ambient temperature. This difference is particularly noticeable when the air conditioner blows directly on people, potentially causing discomfort, especially in hot summers or cold winters. Human temperature perception is relative; if the air conditioner's outlet temperature is too high or too low, even if the average indoor temperature is suitable, it may still cause discomfort and fail to meet the user's needs.

[0004] In conclusion, existing air conditioners do not accurately control the outlet air temperature and cannot meet user needs.

[0005] Accordingly, a new technical solution is needed in this field to solve the above problems. Summary of the Invention

[0006] The present invention aims to solve the above-mentioned technical problems, namely, to solve the problem that the existing air conditioners do not accurately control the outlet air temperature and cannot meet the needs of users.

[0007] In a first aspect, the present invention provides a control method for an air conditioner, the control method comprising: acquiring the air outlet temperature of the air conditioner; adjusting the valve opening of a control valve device by a preset change range based on the air outlet temperature and a set temperature; acquiring the absolute value of the difference between the air outlet temperature and the set temperature at intervals of a first preset time period; and controlling the change of air conditioner operating parameters based on the changing trend of multiple and continuous absolute values ​​if the last absolute value within a preset number of times is greater than a preset value.

[0008] In the preferred technical solution of the above-mentioned air conditioner control method, the step of "controlling the change of air conditioner operating parameters based on the changing trend of multiple and continuous absolute values" specifically includes: if the multiple and continuous absolute values ​​show a gradually decreasing trend, then the compressor frequency and outdoor fan speed of the air conditioner are kept constant, and the valve device is adjusted to adjust the valve opening by a preset change range.

[0009] In the preferred technical scheme of the control method of the air conditioner, the step of "controlling the change of the operation parameter of the air conditioner based on the change trend of the plurality of and continuous absolute values" specifically comprises: if the plurality of and continuous absolute values present a non-gradual decrease trend, determining the change rate of the compressor frequency and the change value of the outdoor fan rotating speed based on the difference between the outlet air temperature and the set temperature; and continuing to change for a second preset time length, and then working with the compressor frequency and the outdoor fan rotating speed at the end of the second preset time length.

[0010] In the preferred technical scheme of the control method of the air conditioner, the control method further comprises: controlling the compressor frequency and the outdoor fan rotating speed at the end of the second time length to work for a third preset time length, and then entering the step of "controlling the valve device to adjust the valve opening degree by a preset change amplitude based on the outlet air temperature and the set temperature".

[0011] In the preferred technical scheme of the control method of the air conditioner, the control method further comprises: if the last absolute value in a preset number of times is less than or equal to a preset value, controlling the air conditioner to operate with the operation parameter at the current time.

[0012] In the preferred technical scheme of the control method of the air conditioner, the control method further comprises: if the last absolute value in a preset number of times is less than or equal to a preset value, after the step of "controlling the air conditioner to operate with the operation parameter at the current time" continues for a fourth preset time length, entering the step of "controlling the valve device to adjust the valve opening degree by a preset change amplitude based on the outlet air temperature and the set temperature".

[0013] In the preferred technical scheme of the control method of the air conditioner, before the step of "controlling the valve device to adjust the valve opening degree by a preset change amplitude based on the outlet air temperature and the set temperature", the control method further comprises: if the last absolute value in a preset number of times is less than or equal to a preset value, determining the change rate of the compressor frequency and the change value of the outdoor fan rotating speed based on the difference between the outlet air temperature and the set temperature; and continuing to change for a fifth preset time length, and then working with the compressor frequency and the outdoor fan rotating speed at the end of the fifth preset time length.

[0014] In the preferred technical scheme of the control method of the air conditioner, the control method further comprises: controlling the compressor frequency and the outdoor fan rotating speed at the end of the fifth time length to work for a sixth preset time length, and then entering the step of "controlling the valve device to adjust the valve opening degree by a preset change amplitude based on the outlet air temperature and the set temperature".

[0015] In the preferred technical solution of the control method of the air conditioner, the step of controlling the valve device to adjust the valve opening degree by a preset variation amplitude based on the outlet air temperature and the set temperature specifically comprises: determining a preset variation rate of the opening degree of the valve device based on the difference between the outlet air temperature and the set temperature, controlling the opening degree of the valve device to vary by a eighth preset time length at a preset variation rate every seventh preset time length, and maintaining the valve opening degree at the end of the eighth preset time length for a seventh preset time length, wherein the sum of the seventh preset time length and the eighth preset time length is equal to the first preset time length.

[0016] In a second aspect, the present application also provides an air conditioner comprising a controller configured to perform the control method according to any one of the preferred technical solutions described above.

[0017] In the case of adopting the technical solution described above, the control method of the present application comprises: obtaining the outlet air temperature of the air conditioner; controlling the valve device to adjust the valve opening degree by a preset variation amplitude based on the outlet air temperature and the set temperature; obtaining the absolute value of the difference between the outlet air temperature and the set temperature every first preset time length; and controlling the operating parameter of the air conditioner to change based on the variation trend of a plurality of and continuous absolute values if the last absolute value is greater than a preset value within a preset number of times. The present application can accurately control the outlet air temperature, meet the user's demand, and control the change of the operating parameter of the air conditioner according to the variation trend of the absolute values of the difference between the outlet air temperature and the set temperature for multiple times, so as to make the outlet air temperature reach the set temperature more quickly. BRIEF DESCRIPTION OF DRAWINGS

[0018] The preferred embodiments of the present application will be described below with reference to the accompanying drawings, in which:

[0019] Figure 1 is the main step flow chart of the control method of the air conditioner of the present application;

[0020] Figure 2 is the detailed step flow chart of the control method of a preferred embodiment of the present application. DETAILED DESCRIPTION

[0021] The preferred embodiments of the present application will be described below with reference to the accompanying drawings. It should be understood by those skilled in the art that these embodiments are only used to explain the technical principles of the present application, and are not intended to limit the protection scope of the present application. Those skilled in the art can make adjustments as needed to adapt to specific application occasions.

[0022] It should be noted that in the description of the present application, the terms "first", "second", "third", "fourth", "fifth", "sixth" are only for descriptive purposes, and cannot be understood as indicating or implying relative importance.

[0023] The air conditioner of the present invention includes a refrigerant circulation loop, and a compressor, an outdoor heat exchanger, a valve device, and an indoor heat exchanger sequentially arranged in the refrigerant circulation loop. The valve device can control the flow rate and pressure of the refrigerant, and change the temperature and pressure of the refrigerant.

[0024] An air conditioner also includes an indoor unit and an outdoor unit. The outdoor unit contains an outdoor fan and an outdoor heat exchanger, while the indoor unit contains an indoor fan and an indoor heat exchanger. The indoor unit has an air outlet, and the indoor fan can drive air to enter the room from the air outlet.

[0025] First refer to Figure 1 ,like Figure 1 As shown, the main steps of the air conditioner control method of the present invention include:

[0026] Step S1: Obtain the air outlet temperature of the air conditioner;

[0027] Step S2: Based on the outlet air temperature and the set temperature, the control valve device adjusts the valve opening by a preset variation range;

[0028] Step S3: At each first preset time interval, obtain the absolute value of the difference between the air conditioner outlet temperature and the set temperature;

[0029] Step S4: If the last absolute value within the preset number of times is greater than the preset value, then control the change of air conditioning operating parameters based on the changing trend of multiple and continuous absolute values.

[0030] In step S1, a temperature sensor can be installed at the air outlet of the indoor unit to obtain the air outlet temperature of the air conditioner, i.e., the air outlet temperature at the air outlet.

[0031] In step S2, based on the difference between the outlet air temperature and the set temperature (which can be the difference between the outlet air temperature and the set temperature, or the difference between the set temperature and the outlet air temperature), a preset variation range of the valve device opening is determined. According to the one-to-one correspondence between different differences and preset variation ranges, the preset variation range of the valve device opening can be determined, and the valve device opening is controlled to change by the preset variation range so that the outlet air temperature is closer to the set temperature.

[0032] In step S3, at each first preset time interval, the absolute value of the difference between the air conditioner outlet temperature and the set temperature is obtained. This can be done by calculating the difference between the outlet temperature and the set temperature and then calculating the absolute value, or by calculating the difference between the set temperature and the outlet temperature and then calculating the absolute value. After several first preset time intervals, the absolute values ​​calculated multiple times are recorded.

[0033] The step S3 can be executed after the step S2 is executed, that is, the opening degree of the valve device is adjusted and then kept unchanged, and then the step S3 is executed to calculate the absolute value multiple times. Alternatively, the end time of the step S2 is the start time of the first first preset time length, or the start time of the step S2 is the start time of the first first preset time length.

[0034] In the step S3, the preset number of times of calculating the absolute value can be set. After multiple and continuous absolute values are recorded, the step S4 is entered. In the step S4, if the last absolute value in the preset number of times is greater than the preset value, it is proved that the difference between the outlet air temperature and the set temperature is still large. Therefore, based on the change trend of the multiple and continuous absolute values, the change of the air conditioner operating parameter is controlled. Based on the change trend, it can be seen whether the current valve opening degree adjustment can make the cooling or heating capacity of the air conditioner meet the requirement that the outlet air temperature approaches the set temperature. If it can meet the requirement, the air conditioner is operated based on the current cooling capacity, or the valve opening degree adjustment speed is continuously adjusted based on the current valve opening degree adjustment speed. If it cannot meet the requirement, other operating parameters of the air conditioner are adjusted to meet the cooling and heating requirements, for example, the operating frequency of the compressor and the rotating speed of the outdoor fan are adjusted.

[0035] Next, refer to Figure 2 The detailed steps of the preferred example of the control method of the air conditioner are as follows:

[0036] Step S101: The change rate of the compressor frequency and the change value of the outdoor fan rotating speed are determined based on the difference between the outlet air temperature and the set temperature. After the fifth preset time length, the compressor frequency and the outdoor fan rotating speed at the end of the fifth preset time length are used to work.

[0037] Step S102: The compressor frequency and the outdoor fan rotating speed at the end of the fifth time length are controlled to work for a sixth preset time length.

[0038] Step S103: The outlet air temperature of the air conditioner is obtained.

[0039] Step S104: Based on the outlet air temperature and the set temperature, the valve device is controlled to adjust the valve opening degree by a preset change amplitude.

[0040] Step S105: The absolute value of the difference between the outlet air temperature and the set temperature of the air conditioner is obtained every first preset time length.

[0041] Step S106: Whether the last absolute value in the preset number of times is greater than the preset value is judged.

[0042] Step S107: Based on the change trend of the multiple and continuous absolute values, the change of the air conditioner operating parameter is controlled.

[0043] Step S1071: If the multiple and continuous absolute values are in a non-decreasing trend, determine the change rate of the compressor frequency and the change value of the outdoor fan speed based on the difference between the outlet air temperature and the set temperature, and work with the compressor frequency and the outdoor fan speed at the end of the second preset time duration after the change for the second preset time duration;

[0044] Step S1072: Control the compressor frequency and the outdoor fan speed at the end of the second time duration to work for a third preset time duration;

[0045] Step S1073: If the multiple and continuous absolute values are in a decreasing trend, control the compressor frequency and the outdoor fan speed of the air conditioner to be unchanged;

[0046] Step S108: Then control the air conditioner to run with the running parameters at the current time;

[0047] Step S109: After the fourth preset time duration, execute step S104.

[0048] In step S101, the change rate of the compressor frequency and the change value of the outdoor fan speed are determined based on the difference between the outlet air temperature and the set temperature, each difference corresponding to a change rate of the compressor frequency, and each difference corresponding to a change value of the outdoor fan speed. Therefore, the change rate of the compressor frequency and the change value of the outdoor fan speed can be determined based on the difference. After determination, the outdoor fan speed is increased by the change value based on the original speed, and the compressor frequency is changed at the determined change rate for a fifth preset time duration of 3s. The compressor frequency and the outdoor fan speed at the end of the fifth preset time duration are worked, and based on this, the fine tuning is performed to change the refrigeration and heating capacity of the air conditioner, so that the actual outlet air temperature is closer to the set temperature. The fifth preset time duration can also be 2s, 4s or 5s, or other values.

[0049] Step S101 is followed by step S102, in which the compressor frequency and the outdoor fan speed at the end of the fifth preset time duration are worked for a sixth preset time duration of 30s, in order to let the air conditioner work with stable refrigeration or heating capacity for a period of time, and then step S103 and the subsequent steps are executed. The sixth preset time duration can also be 40s, 35s, 25s or 20s, or other values.

[0050] In step S103, the outlet air temperature of the air conditioner is obtained. A temperature sensor can be arranged at the outlet of the indoor unit to obtain the outlet air temperature of the air conditioner, i.e. the outlet air temperature at the outlet.

[0051] In step S104, based on the difference between the outlet air temperature and the set temperature, the valve device is determined to adjust the valve opening degree by a preset variation amplitude, each difference corresponds to a preset variation amplitude of the valve device opening degree, and the one-to-one correspondence between the difference and the preset variation amplitude is not described here, and those skilled in the art can set it according to different types of air conditioners, refrigeration or heating capacity.

[0052] In step S105, the first first preset time length is the starting time of step S104, that is, the starting time when the opening degree of the valve device starts to change, and the absolute value of the difference between the outlet air temperature and the set temperature is obtained every first preset time length 20s, that is, the absolute value of the difference between the outlet air temperature and the set temperature is recalculated every first preset time length 20s, and each absolute value is recorded, and the preset number of records is 3 times, and then step S106 is executed to determine whether the last absolute value of the 3 recorded absolute values is greater than the preset value 1℃. If the result of the determination is yes, it proves that the difference between the outlet air temperature and the set temperature is large at this time, and the outlet air temperature cannot meet the demand, so step S107 is executed to control the air conditioner operating parameter change based on the change trend of multiple and continuous absolute values, step S107 includes step S1071 and step S1073. In step S1071, if the multiple and continuous absolute values show a non-decreasing trend, it proves that the current valve opening degree adjustment cannot meet the requirement that the outlet air temperature approaches the set temperature, so the change rate of the compressor frequency and the outdoor fan speed change value are determined based on the difference between the outlet air temperature and the set temperature, and the determined change rate is continuously changed for a second preset time length of 3s, and then the compressor frequency and the outdoor fan speed at the end of the second preset time length are used for work. That is, when the valve opening degree cannot control the outlet air temperature to approach the set temperature, the compressor frequency and the outdoor fan speed are adjusted to control the outlet air temperature to approach the set temperature.

[0053] After step S1071 is executed, step S1072 is executed to control the compressor frequency and the outdoor fan speed at the end of the second time length to work for a third preset time length of 30s, and then step S104 is executed; in other embodiments, step S1072 can be omitted, that is, after step S1071 is executed, step S104 is directly executed.

[0054] If the multiple and continuous absolute values show a gradually decreasing trend, it proves that the outlet air temperature is gradually approaching the set temperature, and the valve opening degree change of the valve device can control the outlet air temperature to approach the set temperature, so step S1073 is executed to control the air conditioner compressor frequency and the outdoor fan speed to be unchanged, and other parameters of the air conditioner are unchanged, and then step S104 and the subsequent steps are executed.

[0055] In step S106, if the last absolute value is less than or equal to the preset value within the preset number of times, it proves that the difference between the outlet air temperature and the set temperature is within the allowable error range, and the outlet air temperature is closer to the set temperature. Therefore, step S108 is executed to control the air conditioner to run at the running parameters at the current time, that is, the running parameters of the air conditioner corresponding to the time when the last absolute value is calculated to be less than or equal to the preset value, that is, the valve opening degree, the compressor frequency and the outdoor fan speed at the current time are maintained, and then step S109 is executed, that is, the running parameters at the current time in step S108 are continued for a fourth preset time length of 3 minutes, and then step S104 is returned to execute. The fourth preset time length can also be 4 minutes, 2 minutes, or other values.

[0056] Continuing to refer to Figure 2 In step S104, the preset change amplitude can be a change value of the valve opening degree from a certain opening degree to another opening degree, or the following:

[0057] Based on the difference between the outlet air temperature and the set temperature, a preset change rate of the opening degree of the valve device is determined, the opening degree of the valve device is changed at the preset change rate every interval of a seventh preset time length of 10s for an eighth preset time length of 10s, and the valve opening degree at the end of the eighth preset time length of 10s is maintained for a seventh preset time length of 10s. Based on this, the valve opening degree adjustment is preset to change; that is, the valve opening degree changes at the preset change rate for 0-10s, the valve opening degree at the end of 10s is maintained for 10-20s, the valve opening degree changes at the preset change rate for 20-30s, the valve opening degree at the end of 30s is maintained for 30-40s, and the adjustment is sequentially cycled. That is, the valve opening degree is first adjusted at a determined preset change rate for a period of time, and then the valve opening degree is maintained unchanged for a period of time. The adjustment is sequentially adjusted according to the above cycle, and the valve opening degree is adjusted after the end of the Nth seventh preset time length (N≥2). For example, when the valve opening degree is adjusted at 20s, the preset change rate can be determined based on the initial difference, or the preset change rate can be determined based on the real-time difference.

[0058] The preset change rate of the valve opening degree of the valve device, the compressor frequency change rate and the outdoor fan speed change value are determined according to the following table:

[0059]

[0060] In the above table, Ts is the actual outlet air temperature, i.e., the outlet air temperature at the outlet of the indoor unit of the air conditioner, T0 represents the set temperature, i.e., the outlet air temperature desired to be reached by the user through the operation of the controller or the operation panel; the frequency change rate column is the compressor frequency change rate, a positive value is a frequency increase adjustment, and a negative value is a frequency decrease adjustment; the valve opening change rate column is the valve opening change rate of the valve device, a positive value is an increase in the valve opening, and a negative value is a decrease in the valve opening; and a positive value of the outdoor fan speed change is an increase in the speed.

[0061] The corresponding relationship between the difference and the frequency change rate, the corresponding relationship between the difference and the valve opening change rate, and the corresponding relationship between the difference and the outdoor fan speed change in the above table are not restrictive, and a person skilled in the art can change the specific values in the table according to actual conditions.

[0062] It should be noted that the present application does not make any limitation on the specific values of the first preset time length, the second preset time length, the third preset time length, the fourth preset time length, the fifth preset time length, the sixth preset time length, the seventh preset time length, and the eighth preset time length, and a person skilled in the art can set them according to actual conditions,

[0063] In the preferred embodiment, the sum of the seventh preset time length and the eighth preset time length is equal to the first preset time length, so as to ensure that after adjusting for a period of time and stabilizing for a period of time, the outlet air temperature is accurately measured, and the outlet air temperature is measured during the adjustment period.

[0064] In other embodiments, the second preset time length and the fifth preset time length are the same, and the third preset time length and the sixth preset time length are the same.

[0065] In other embodiments, step S102 can be omitted; in other embodiments, steps S101 and S102 can be omitted; and in other embodiments, step S1072 can be omitted.

[0066] In other embodiments, the change rate of the valve opening, the change rate of the compressor frequency, and the change value of the outdoor fan speed can also be determined based on the difference between the set temperature and the outlet air temperature, which can be converted according to the table described above.

[0067] In other embodiments, the rate of change of the opening degree of the valve device, the rate of change of the compressor frequency and the rate of change of the outdoor fan speed are determined based on the difference between the outlet air temperature and the set temperature, and the difference corresponds to the rate of change of the outdoor fan speed, then in step S101, the compressor frequency is controlled to change at the determined rate for a fifth preset time length, and the outdoor fan speed is controlled to change at the determined rate for a fifth preset time length, and the others are the same as described above; in step S1071, the compressor frequency is controlled to change at the determined rate for a second preset time length, and the outdoor fan speed is controlled to change at the determined rate for a second preset time length, and the others are the same as described above.

[0068] In other embodiments, step S1071 is: if the multiple and continuous absolute values are not gradually reduced, the rate of change of the compressor frequency is determined based on the difference between the outlet air temperature and the set temperature, and the compressor frequency is controlled to change for a second preset time length, and then the compressor frequency at the end of the second preset time length is used for operation.

[0069] In other embodiments, step S1071 is: if the multiple and continuous absolute values are not gradually reduced, the rate of change of the outdoor fan speed is determined based on the difference between the outlet air temperature and the set temperature, and the outdoor fan speed is controlled to change for a second preset time length, and then the outdoor fan speed at the end of the second preset time length is used for operation.

[0070] It should be noted that the preset number of 3 is only a preferred setting method, and the preset number can also be 2, 4, 5 or other values, which can be set by a person skilled in the art according to actual conditions.

[0071] In addition, it should be noted that the preset value of 1℃ is only a preferred setting method, and it can also be 0.9℃, 0.8℃, 0.7℃, 0.6℃, 0.5℃ or other values, which can be set by a person skilled in the art according to actual conditions.

[0072] In the present application, the compressor frequency, the outdoor fan speed and the opening degree of the valve device all have maximum and minimum limit values, if the maximum limit value is reached, the increase adjustment is performed according to the maximum limit value, and if the minimum limit value is reached, the decrease adjustment is performed according to the minimum limit value.

[0073] In a second aspect, the present application also claims a kind of air conditioner, and the air conditioner includes controller, and the controller is configured to be able to execute the control method described in any one of the above embodiments.

[0074] The technical scheme of the present application has been described in combination with the preferred embodiments shown in the drawings, but it is easy for those skilled in the art to understand that the protection scope of the present application is obviously not limited to these specific embodiments. Those skilled in the art can make equivalent changes or replacements to the related technical features without departing from the principles of the present application, and the technical schemes after the changes or replacements will all fall within the protection scope of the present application.

Claims

1. A control method of an air conditioner, characterized by, The control method comprises: obtaining an outlet air temperature of the air conditioner; controlling a valve device to adjust a valve opening degree at a preset variation amplitude based on the outlet air temperature and a set temperature; obtaining an absolute value of a difference between the outlet air temperature and the set temperature every interval of a first preset time length; if the last absolute value in a preset number of times is greater than a preset value, controlling a change of an operating parameter of the air conditioner based on a variation trend of a plurality of and continuous absolute values, and the steps comprise: if the plurality of and continuous absolute values present a gradually decreasing trend, controlling a compressor frequency and an outdoor fan rotating speed of the air conditioner to be unchanged, and controlling the valve device to adjust the valve opening degree at the preset variation amplitude.

2. The control method of the air conditioner according to claim 1, characterized by, The step of "controlling a change of an operating parameter of the air conditioner based on a variation trend of a plurality of and continuous absolute values" specifically comprises: if the plurality of and continuous absolute values present a non-gradually decreasing trend, determining a variation rate of the compressor frequency and a variation value of the outdoor fan rotating speed based on a difference between the outlet air temperature and the set temperature; continuously changing for a second preset time length, and then working at the compressor frequency and the outdoor fan rotating speed at the end of the second preset time length.

3. The control method of the air conditioner according to claim 2, characterized by, The control method further comprises: controlling to work at the compressor frequency and the outdoor fan rotating speed at the end of the second time length for a third preset time length, and then entering the step of "controlling a valve device to adjust a valve opening degree at a preset variation amplitude based on the outlet air temperature and a set temperature".

4. The control method of the air conditioner according to claim 1, characterized by, The control method further comprises: if the last absolute value in a preset number of times is less than or equal to a preset value, controlling the air conditioner to operate at an operating parameter at a current time.

5. The control method of the air conditioner according to claim 4, characterized by, The control method further comprises: if the last absolute value in a preset number of times is less than or equal to a preset value, after the step of "controlling the air conditioner to operate at an operating parameter at a current time" lasts for a fourth preset time length, entering the step of "controlling a valve device to adjust a valve opening degree at a preset variation amplitude based on the outlet air temperature and a set temperature".

6. The control method of the air conditioner according to claim 1, characterized by, Before the step of "controlling a valve device to adjust a valve opening degree at a preset variation amplitude based on the outlet air temperature and a set temperature", the control method further comprises: determining a variation rate of the compressor frequency and a variation value of the outdoor fan rotating speed based on a difference between the outlet air temperature and the set temperature; continuously changing for a fifth preset time length, and then working at the compressor frequency and the outdoor fan rotating speed at the end of the fifth preset time length.

7. The control method of the air conditioner according to claim 6, characterized by, controlling to work at the compressor frequency and the outdoor fan rotating speed at the end of the fifth time length for a sixth preset time length, and then entering the step of "controlling a valve device to adjust a valve opening degree at a preset variation amplitude based on the outlet air temperature and a set temperature".

8. The control method of the air conditioner according to claim 1, characterized by, The step of "controlling a valve device to adjust a valve opening degree at a preset variation amplitude based on the outlet air temperature and a set temperature" specifically comprises: determining a preset variation rate of the opening degree of the valve device based on a difference between the outlet air temperature and the set temperature, controlling the opening degree of the valve device to change at the preset variation rate every interval of a seventh preset time length for an eighth preset time length, and maintaining the valve opening degree for the seventh preset time length at the end of the eighth preset time length; wherein the sum of the seventh preset time length and the eighth preset time length is equal to the first preset time length.

9. An air conditioner characterized by comprising: The air conditioner comprises a controller configured to be capable of executing the control method in any one of claims 1 to 8.

Images