An air conditioner and its high-temperature operation control method

Abstract

The present invention relates to the technical field of air conditioning equipment, and particularly to an air conditioner and a high-temperature operation control method thereof. When the air conditioner is under high-load operation conditions, by pre-adjusting the target operation frequency of the compressor, the increase rate of the compressor frequency is reduced, so as to avoid the situation that the compressor frequency decreases and the compressor operation frequency continuously remains at a low rotation speed due to the excessive exhaust temperature, the temperature of the outdoor heat exchanger during the refrigeration operation or the temperature of the indoor heat exchanger during the heating operation, resulting in the inability to guarantee the refrigeration effect or the heating effect of the air conditioner. After the air conditioner operates in the pre-frequency reduction operation mode for a period of time, if the unit operates stably and meets the frequency increase conditions, the frequency reduction amplitude of the pre-frequency reduction is weakened, and the compressor operation frequency is slightly increased to optimize and improve the operation effect of the air conditioner as much as possible.

Description

Technical Field

[0001] The present invention relates to the technical field of air conditioning equipment, and particularly to an air conditioner and a high-temperature operation control method thereof. Background Art

[0002] In the existing air conditioner, during operation, when the exhaust temperature of the compressor is too high, the temperature of the outdoor heat exchanger is too high during the refrigeration operation, or the temperature of the indoor heat exchanger is too high during the heating operation, the operating frequency of the compressor will be restricted and the frequency will be reduced.

[0003] After the compressor frequency is reduced, when the exhaust temperature of the compressor, the temperature of the outdoor heat exchanger during the refrigeration operation, or the temperature of the indoor heat exchanger during the heating operation drops to a certain value, the compressor frequency will increase again to ensure that the air conditioner outputs sufficient cooling capacity or heating capacity.

[0004] During the operation of the compressor, its target operating frequency is often adjusted according to the indoor ambient temperature, the outdoor ambient temperature, the temperature of the indoor heat exchanger, and the temperature of the outdoor heat exchanger. Under certain conditions, after the compressor frequency is reduced, the exhaust temperature of the compressor, the temperature of the outdoor heat exchanger during the refrigeration operation, or the temperature of the indoor heat exchanger during the heating operation cannot drop to a temperature that is sufficient to allow the compressor frequency to increase again, and the compressor continues to operate at a low frequency, resulting in the cooling effect or heating effect of the air conditioner not being guaranteed. Summary of the Invention

[0005] In order to solve the above problems, the first object of the present invention is to provide a high-temperature operation control method for an air conditioner. When the air conditioner is under high-load operation conditions, by pre-adjusting the target operating frequency of the compressor, the rate of increase of the compressor frequency is reduced, avoiding the situation where the exhaust temperature, the temperature of the outdoor heat exchanger during the refrigeration operation, or the temperature of the indoor heat exchanger during the heating operation is too high, resulting in a reduction in the compressor frequency and the compressor operating frequency continuously remaining at a low speed, which causes the cooling effect or heating effect of the air conditioner not to be guaranteed. The second object of the present invention is to provide an air conditioner containing the above high-temperature operation control method.

[0006] To achieve the above object, the present invention adopts the following technical solutions: A high-temperature operation control method for an air conditioner, which is applied to the air conditioner. The air conditioner includes a controller, an indoor unit, and an outdoor unit; the indoor unit includes an indoor heat exchanger, an indoor ambient temperature sensor, an indoor heat exchanger temperature sensor, and an indoor fan; the outdoor unit includes a compressor, a four-way reversing valve, an outdoor heat exchanger, an outdoor ambient temperature sensor, an outdoor heat exchanger temperature sensor, an outdoor fan, an outdoor throttling mechanism for controlling the flow rate, and an exhaust temperature sensor for detecting the temperature of the refrigerant discharged by the compressor; the indoor heat exchanger and the outdoor heat exchanger form a loop through a first refrigerant connection pipe and a second refrigerant connection pipe, the compressor and the outdoor throttling mechanism are arranged in the above loop, and the four-way reversing valve is used to switch the valve ports so that the air conditioner has a refrigeration mode and a heating mode; it is characterized in that: the control method is as follows:

[0007] In the refrigeration mode:

[0008] Step 1: The air conditioner is turned on, the refrigeration mode is turned on, the controller obtains the outdoor ambient temperature To and judges whether To is within the preset threshold a. If so, the controller displays the outdoor ambient temperature pre-frequency reduction processing mark Xo = 0; if not, the controller displays the outdoor ambient temperature pre-frequency reduction processing mark Xo = 1;

[0009] Step 2: The controller obtains the outdoor heat exchanger temperature Tc and the compressor exhaust temperature Td, and calculates the compressor exhaust temperature change rate △Td and the outdoor heat exchanger temperature change rate △Tc per unit time; the controller judges whether △Tc is within the preset threshold c. If so, the controller displays the outdoor ambient temperature pre-frequency reduction processing mark Xc = 0; if not, the controller displays the outdoor ambient temperature pre-frequency reduction processing mark Xc = 1; the controller judges whether △Td is within the preset threshold d. If so, the controller displays the outdoor ambient temperature pre-frequency reduction processing mark Xd = 0; if not, the controller displays the outdoor ambient temperature pre-frequency reduction processing mark Xd = 1;

[0010] Step 3: The controller calculates the value of the parameter X, X = Xo + Xc + Xd, and reads the compressor target preset frequency Ft under the environmental conditions preset by the air conditioner manufacturer; the controller judges whether X is equal to 0. If it is equal to 0, the air conditioner target operation frequency Ft' is the same as the compressor target preset frequency Ft, and the air conditioner continues to operate in the normal mode or shuts down to end the refrigeration mode; if it is not equal to 0, the air conditioner operates in the pre-frequency reduction mode, and then enters Step 4.

[0011] Step 4: Based on the value of parameter X, the controller reads the revision times parameter e of the preset compressor operating frequency correction value and the value of the compressor target operating frequency correction value △F; based on the value of e, the controller reads the revision coefficient α of the compressor target operating frequency correction value under the preset refrigeration mode; the controller obtains the value of the air conditioner target operating frequency Ft' under the environmental conditions through the calculation formula Ft’ = Ft - α△F and adjusts the operating frequency of the compressor to Ft’; after the compressor operating frequency is adjusted, if the air conditioner continues to operate, go to Step 5; if the air conditioner shuts down, end the refrigeration mode.

[0012] Step 5: Statistically record the operating time t, and the controller determines whether the operating time t is greater than the preset threshold f. If t ≥ f, the controller determines whether Td and Te are stable and meet the frequency increase conditions. If Td and Te are stable and meet the frequency increase conditions, it is determined whether the value of e is equal to 3. If e = 3, clear the statistical data of the operating time t and go to Step 1; if e is not equal to 3, increase the revision times of the compressor operating frequency correction value by one, that is, e = e + 1, clear the statistical data of the operating time t, and go to Step 1;

[0013] In the heating mode:

[0014] Step 1: The air conditioner is turned on, the heating mode is turned on, the controller obtains the indoor environmental temperature Ti and determines whether Ti is within the preset threshold b. If so, the indoor environmental temperature pre-frequency reduction processing mark Xi = 0 is displayed on the controller; if not, the indoor environmental temperature pre-frequency reduction processing mark Xi = 1 is displayed on the controller.

[0015] Step 2: The controller obtains the indoor heat exchanger temperature Te and the compressor discharge temperature Td, and calculates the compressor discharge temperature change rate △Td and the indoor heat exchanger temperature change rate △Te per unit time; the controller determines whether △Te is within the preset threshold c. If so, the indoor environmental temperature pre-frequency reduction processing mark Xe = 0 is displayed on the controller; if not, the indoor environmental temperature pre-frequency reduction processing mark Xe = 1 is displayed on the controller; the controller determines whether △Td is within the preset threshold d. If so, the indoor environmental temperature pre-frequency reduction processing mark Xd = 0 is displayed on the controller; if not, the indoor environmental temperature pre-frequency reduction processing mark Xd = 1 is displayed on the controller.

[0016] Step 3: The controller calculates the value of parameter X, X = Xi + Xe + Xd, and reads the compressor target preset frequency Ft under the environmental conditions preset by the air conditioner manufacturer; the controller determines whether X is equal to 0. If it is equal to 0, the air conditioner target operating frequency Ft’ is the same as the compressor target preset frequency Ft, and the air conditioner continues to operate in the normal mode or shuts down to end the heating mode; if it is not equal to 0, the air conditioner operates in the pre-frequency reduction mode, and then go to Step 4.

[0017] Step 4: Based on the value of parameter X, the controller reads the revision number parameter e of the preset compressor operating frequency correction value and the value of the compressor target operating frequency correction value △F; based on the value of e, the controller reads the value of the revision coefficient β of the compressor target operating frequency correction value in the preset heating mode; the controller obtains the value of the air conditioner target operating frequency Ft' under the environmental conditions through the calculation formula Ft' = Ft - β△F and adjusts the operating frequency of the compressor to Ft'; after the compressor operating frequency is adjusted, if the air conditioner continues to operate, go to Step 5; if the air conditioner shuts down, end the cooling mode.

[0018] Step 5: Statistically record the operating time t, and the controller judges whether the operating time t is greater than the preset threshold f. If t ≥ f, the controller judges whether Td and Te are stable and meet the frequency increase condition. If Td and Te are stable and meet the frequency increase condition, it judges whether the value of e is equal to 3. If e = 3, clear the statistical data of the operating time t and go to Step 1; if e is not equal to 3, increase the revision number of the compressor operating frequency correction value by one, that is, e = e + 1, clear the statistical data of the operating time t, and go to Step 1;

[0019] Preferably, when the cooling or heating mode is turned on, the data of parameters X, t, and e are reset to zero.

[0020] Preferably, X is a statistical parameter for the pre-frequency reduction operation mode, and the value of X is 0, 1, 2, 3; X = 0 is the normal operation mode, X = 1 is the pre-frequency reduction operation mode 1, X = 2 is the pre-frequency reduction operation mode 2, and X = 3 is the pre-frequency reduction operation mode 3.

[0021] Preferably, when the value of X is 1, 2, 3, the corresponding values of △F are 10, 15, 20; when the value of e is 0, 1, 2, 3, the corresponding values of α are 1, 0.8, 0.5, 0.2, and the corresponding values of β are 1, 0.7, 0.5, 0.3.

[0022] Preferably, the controller includes an indoor control mechanism and an outdoor control mechanism that can communicate with each other and control the indoor unit and the outdoor unit respectively.

[0023] An air conditioner that applies the high-temperature operation control method of the air conditioner described in any one of the above.

[0024] With the above technical solution, during the refrigeration operation of the air conditioner, the compressor discharge temperature, the outdoor ambient temperature, and the outdoor heat exchanger temperature are detected to determine whether there is a risk of overloading the air conditioner. When there is a risk of overloading the air conditioner, the operation frequency of the air conditioner compressor is pre-reduced in advance to avoid the situation where the compressor discharge temperature and the outdoor heat exchanger temperature are too high due to too high a compressor operation frequency, resulting in excessive self-protection of the air conditioner and thus poor refrigeration operation effect.

[0025] Similarly, during the heating operation of the air conditioner, the compressor discharge temperature, the indoor ambient temperature, and the indoor heat exchanger temperature are detected to determine whether there is a risk of overloading the air conditioner. When there is a risk of overloading the air conditioner, the operation frequency of the air conditioner compressor is pre-reduced in advance to avoid the situation where the compressor discharge temperature and the indoor heat exchanger temperature are too high due to too high a compressor operation frequency, resulting in excessive self-protection of the air conditioner and thus poor heating operation effect.

[0026] Moreover, during the above refrigeration or heating operation, the method can effectively determine the number of risk conditions that cause the air conditioner to operate overloaded and classify the overloaded operation situation, which is clear and organized. The more risk conditions of overloaded operation, the greater the frequency reduction amplitude of the pre-frequency reduction.

[0027] In addition, after the air conditioner operates in the pre-frequency reduction operation mode for a period of time, if the unit operates stably and meets the frequency increase conditions, the frequency reduction amplitude of the pre-frequency reduction is weakened, and the compressor operation frequency is slightly increased to optimize and improve the operation effect of the air conditioner as much as possible. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1 It is a schematic structural diagram of the air conditioner involved in the present invention.

[0029] Figure 2 It is a schematic control logic diagram for adjusting the compressor frequency of the air conditioner involved in the present invention in the refrigeration operation mode.

[0030] Figure 3 It is a schematic control logic diagram for adjusting the compressor frequency of the air conditioner involved in the present invention in the heating operation mode.

[0031] Figure 4 It is the value of the correction value △F of the target operation frequency of the compressor of the air conditioner involved in the present invention.

[0032] Figure 5 It is the value of the revision coefficient α of the correction value of the target operation frequency of the compressor during the refrigeration operation of the air conditioner involved in the present invention.

[0033] Figure 6The value of the revision coefficient β for the correction value of the compressor target operating frequency during the heating operation of the air conditioner involved in the present invention. Detailed implementation manners

[0034] The embodiments of the present invention will be described in detail below. Examples of the embodiments are shown in the drawings, where the same or similar reference numerals indicate the same or similar elements or elements with the same or similar functions throughout. The embodiments described below with reference to the drawings are exemplary and are intended to explain the present invention, and should not be construed as limiting the present invention.

[0035] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "clockwise", "counterclockwise", etc. indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings. They are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and thus should not be construed as limiting the present invention.

[0036] In addition, the terms "first" and "second" are only used for descriptive purposes and should not be construed as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Thus, the features defined with "first" and "second" may explicitly or implicitly include one or more of such features. In the description of the present invention, unless otherwise specified, the meaning of "plural" is two or more, unless otherwise clearly defined.

[0037] In the present invention, unless otherwise clearly specified and defined, the terms "mounted", "connected", "connected to", "fixed", etc. should be understood in a broad sense. For example, it may be a fixed connection, a detachable connection, or an integral connection; it may be a mechanical connection or an electrical connection; it may be directly connected or indirectly connected through an intermediate medium, and it may be the communication inside two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0038] In the present invention, unless otherwise clearly specified and defined, the first feature being "above" or "below" the second feature may include the direct contact between the first and second features, or may include the situation where the first and second features are not in direct contact but in contact through additional features therebetween. Moreover, the first feature being "above", "over" and "on top of" the second feature includes that the first feature is directly above and obliquely above the second feature, or merely indicates that the horizontal height of the first feature is higher than that of the second feature. The first feature being "below", "beneath" and "underneath" the second feature includes that the first feature is directly below and obliquely below the second feature, or merely indicates that the horizontal height of the first feature is lower than that of the second feature. Embodiment 1:

[0039] As Figures 1-6 A high-temperature operation control method for an air conditioner as shown is applied to the air conditioner. The air conditioner includes a controller, an indoor unit 10 and an outdoor unit 20; the indoor unit 10 includes an indoor heat exchanger 101, an indoor ambient temperature sensor 102, an indoor heat exchanger temperature sensor 103 and an indoor fan 104; the outdoor unit 20 includes a compressor 201, a four-way reversing valve 202, an outdoor heat exchanger 203, an outdoor ambient temperature sensor 204, an outdoor heat exchanger temperature sensor 205, an outdoor fan 207, an outdoor throttling mechanism 206 for controlling the flow rate, and an exhaust temperature sensor 208 for detecting the temperature of the refrigerant discharged by the compressor 201; the indoor heat exchanger 101 and the outdoor heat exchanger 203 form a loop through a first refrigerant connection pipe 30 and a second refrigerant connection pipe 40, the compressor 201 and the outdoor throttling mechanism 206 are arranged in the above loop, and the four-way reversing valve 202 is used to switch the valve ports so that the air conditioner has a refrigeration mode and a heating mode; the control method is as follows:

[0040] In the refrigeration mode:

[0041] Step 1: The air conditioner is turned on, the refrigeration mode is turned on, the controller obtains the outdoor ambient temperature To and judges whether To is within a preset threshold a. If so, the controller displays the outdoor ambient temperature pre-frequency reduction processing mark Xo = 0; if not, the controller displays the outdoor ambient temperature pre-frequency reduction processing mark Xo = 1;

[0042] Step 2: The controller obtains the outdoor heat exchanger temperature Tc and the compressor discharge temperature Td, and calculates the change rate of the compressor discharge temperature △Td and the change rate of the outdoor heat exchanger temperature △Tc per unit time; the controller determines whether △Tc is within the preset threshold c, if so, the controller displays the outdoor ambient temperature pre-frequency reduction processing mark Xc = 0; if not, the controller displays the outdoor ambient temperature pre-frequency reduction processing mark Xc = 1; the controller determines whether △Td is within the preset threshold d, if so, the controller displays the outdoor ambient temperature pre-frequency reduction processing mark Xd = 0; if not, the controller displays the outdoor ambient temperature pre-frequency reduction processing mark Xd = 1;

[0043] Step 3: The controller calculates the value of parameter X, X = Xo + Xc + Xd, and reads the compressor target preset frequency Ft under the environmental conditions preset by the air conditioner manufacturer; the controller determines whether X is equal to 0, if equal to 0, the air conditioner target operating frequency Ft’ is the same as the compressor target preset frequency Ft, and the air conditioner continues to operate in the normal mode or shuts down to end the cooling mode; if not equal to 0, the air conditioner operates in the pre-frequency reduction mode, and then enters Step 4.

[0044] Step 4: Based on the value of parameter X, the controller reads the revision times parameter e of the preset compressor operating frequency correction value and the value of the compressor target operating frequency correction value △F; based on the value of e, the controller reads the value of the revision coefficient α of the preset compressor target operating frequency correction value in the cooling mode; the controller obtains the value of the air conditioner target operating frequency Ft’ under the environmental conditions through the calculation formula Ft’ = Ft - α△F and adjusts the operating frequency of the compressor to Ft’; after the compressor operating frequency is adjusted, if the air conditioner continues to operate, it enters Step 5; if the air conditioner shuts down, the cooling mode ends.

[0045] Step 5: Statistically record the operating time t, and the controller determines whether the operating time t is greater than the preset threshold f. If t ≥ f, the controller determines whether Td and Te are stable and meet the frequency increase conditions. If Td and Te are stable and meet the frequency increase conditions, it is determined whether the value of e is equal to 3. If e = 3, clear the statistical data of the operating time t and enter Step 1; if e is not equal to 3, increase the revision times of the compressor operating frequency correction value by one, that is, e = e + 1, clear the statistical data of the operating time t, and enter Step 1;

[0046] In the heating mode:

[0047] Step 1: The air conditioner is turned on, the heating mode is turned on, the controller obtains the indoor ambient temperature Ti and determines whether Ti is within the preset threshold b. If so, the controller displays the indoor ambient temperature pre-frequency reduction processing mark Xi = 0; if not, the controller displays the indoor ambient temperature pre-frequency reduction processing mark Xi = 1;

[0048] Step 2: The controller obtains the indoor heat exchanger temperature Te and the compressor discharge temperature Td, and calculates the change rate of the compressor discharge temperature △Td and the change rate of the indoor heat exchanger temperature △Te per unit time; the controller determines whether △Te is within a preset threshold c. If so, the indoor environment temperature pre-frequency reduction processing mark Xe = 0 is displayed on the controller; if not, the indoor environment temperature pre-frequency reduction processing mark Xe = 1 is displayed on the controller; the controller determines whether △Td is within a preset threshold d. If so, the indoor environment temperature pre-frequency reduction processing mark Xd = 0 is displayed on the controller; if not, the indoor environment temperature pre-frequency reduction processing mark Xd = 1 is displayed on the controller.

[0049] Step 3: The controller calculates the value of parameter X, X = Xi + Xe + Xd, and reads the compressor target preset frequency Ft under the environmental conditions preset by the air conditioner manufacturer; the controller determines whether X is equal to 0. If it is equal to 0, the air conditioner target operating frequency Ft’ is the same as the compressor target preset frequency Ft, and the air conditioner continues to operate in the normal mode or shuts down to end the heating mode; if it is not equal to 0, the air conditioner operates in the pre-frequency reduction mode, and then enters Step 4.

[0050] Step 4: Based on the value of parameter X, the controller reads the revised number parameter e of the preset compressor operating frequency correction value and the value of the compressor target operating frequency correction value △F; based on the value of e, the controller reads the revised coefficient β of the preset compressor target operating frequency correction value in the heating mode; the controller obtains the value of the air conditioner target operating frequency Ft’ under the environmental conditions through the calculation formula Ft’ = Ft - β△F and adjusts the operating frequency of the compressor to Ft’; after the compressor operating frequency is adjusted, if the air conditioner continues to operate, it enters Step 5; if the air conditioner shuts down, the cooling mode ends.

[0051] Step 5: The operating time t is statistically counted. The controller determines whether the operating time t is greater than the preset threshold f. If t ≥ f, the controller determines whether Td and Te are stable and meet the frequency increase conditions. If Td and Te are stable and meet the frequency increase conditions, it is determined whether the value of e is equal to 3. If e = 3, the statistical data of the operating time t is cleared, and it enters Step 1; if e is not equal to 3, the revised number of the compressor operating frequency correction value is increased by one, that is, e = e + 1, the statistical data of the operating time t is cleared, and it enters Step 1.

[0052] Further, when the cooling or heating mode is turned on, the data of parameters X, t, and e are reset to zero.

[0053] Further, X is a statistical parameter for the pre-frequency reduction operation mode, and X takes values of 0, 1, 2, 3; X = 0 is the normal operation mode, X = 1 is the pre-frequency reduction operation mode 1, X = 2 is the pre-frequency reduction operation mode 2, and X = 3 is the pre-frequency reduction operation mode 3.

[0054] Further, when the value of X is 1, 2, or 3, the corresponding values of △F are 10, 15, and 20; when the value of e is 0, 1, 2, or 3, the corresponding values of α are 1, 0.8, 0.5, and 0.2, and the corresponding values of β are 1, 0.7, 0.5, and 0.3.

[0055] Further, the controller includes an indoor control mechanism 105 and an outdoor control mechanism 209 that can communicate with each other and control the indoor unit 10 and the outdoor unit 20 respectively.

[0056] In this embodiment, as Figure 2 shown, the specific steps of the control logic for adjusting the compressor frequency in the cooling operation mode of the air conditioner are as follows:

[0057] S0: Start the cooling operation, and then enter step S1;

[0058] S1: In step S1, the data of the statistical parameters X, t, and e are reset to zero, and then enter step S2;

[0059] S2: In step S2, detect the outdoor ambient temperature To, and then enter step S3;

[0060] S3: In step S3, determine whether the outdoor ambient temperature To is greater than the preset threshold a. If To ≥ a, enter step S4; otherwise, enter step S5;

[0061] S4: In step S4, set Xo = 1, and then enter step S6;

[0062] S5: In step S5, set Xo = 0, and then enter step S6;

[0063] S6: In step S6, detect Tc and Td, and calculate the change rate △Tc of Tc and the change rate △Td of Td, and then enter step S7;

[0064] S7: In step S7, determine whether △Tc is greater than the preset threshold c. If △Tc ≥ c, enter step S8; otherwise, enter step S9;

[0065] S8: In step S8, set Xc = 1, and then enter step S10;

[0066] S9: In step S9, set Xc = 0, and then enter step S10;

[0067] S10: In step S7, determine whether △Td is greater than the preset threshold d. If △Td ≥ d, enter step S11; otherwise, enter step S12;

[0068] S11: In step S11, set Xd = 1, then go to step S13;

[0069] S12: In step S12, set Xd = 0, then go to step S13;

[0070] S13: In step S13, calculate the value of X, X = Xo + Xd + Xc, then go to step S14;

[0071] S14: In step S14, according to the environment where the air conditioner is located, read the target preset frequency Ft of the compressor under the environmental conditions preset by the air conditioner manufacturer, then go to step S15;

[0072] S15: In step S15, judge whether the value of X is equal to 0. If X = 0, then go to step S16, otherwise go to step S18;

[0073] S16: In step S16, the target operating frequency Ft' of the air conditioner is the same as the target preset frequency Ft of the compressor, that is, Ft' = Ft, and the air conditioner is set to operate in the normal mode;

[0074] S17: In step S17, judge whether the air conditioner receives a shutdown signal. If the air conditioner receives a shutdown signal, then go to step S27, otherwise return to step S1;

[0075] S18: In step S18, the air conditioner is set to operate in the pre-frequency-down operation mode. Read the data of △F and α according to the value of X and the value of e, then go to step S19;

[0076] S19: In step S19, the target operating frequency Ft' of the air conditioner is set as Ft' = Ft - α△F, then go to step S20;

[0077] S20: In step S20, judge whether the air conditioner receives a shutdown signal. If the air conditioner receives a shutdown signal, then go to step S27, otherwise go to step S21;

[0078] S21: In step S21, count the running time t, then go to step S22;

[0079] S22: In step S22, judge whether the running time t is greater than the preset threshold f. If t ≥ f, then go to step S23, otherwise return to step S20;

[0080] S23: In step S23, judge whether Td and Te are stable and meet the frequency-up condition. If Td and Te are stable and meet the frequency-up condition, then go to step S24, otherwise go to step S25;

[0081] S24: In step S24, it is judged whether the value of e is equal to 3. If e = 3, go to step S25; otherwise, go to step S26;

[0082] S25: In step S25, clear the statistical data of the running time t, and then go to step S2;

[0083] S26: In step S26, increase the value of e by 1, that is, e = e + 1, and then go to step S25;

[0084] S27: In step S27, perform a shutdown process on the air conditioner, and then go to step S28;

[0085] S28: In step S28, end the cooling operation.

[0086] In this embodiment, as Figure 3 shown, the specific steps of the control logic for adjusting the compressor frequency of the air conditioner in the heating operation mode are as follows:

[0087] S0: Start the heating operation, and then go to step S1;

[0088] S1: In step S1, reset the data of the statistical parameters X, t, and e to zero, and then go to step S2;

[0089] S2: In step S2, detect the indoor ambient temperature Ti, and then go to step S3;

[0090] S3: In step S3, judge whether the indoor ambient temperature Ti is greater than the preset threshold b. If Ti ≥ b, go to step S4; otherwise, go to step S5;

[0091] S4: In step S4, set Xi = 1, and then go to step S6;

[0092] S5: In step S5, set Xi = 0, and then go to step S6;

[0093] S6: In step S6, detect Te and Td, and calculate the change rate △Te of Te and the change rate △Td of Td, and then go to step S7;

[0094] S7: In step S7, judge whether △Te is greater than the preset threshold c. If △Te ≥ c, go to step S8; otherwise, go to step S9;

[0095] S8: In step S8, set Xe = 1, and then go to step S10;

[0096] S9: In step S9, set Xe = 0, and then go to step S10;

[0097] S10: In step S7, determine whether △Td is greater than the preset threshold d. If △Td ≥ d, then proceed to step S11; otherwise, proceed to step S12;

[0098] S11: In step S11, set Xd = 1, and then proceed to step S13;

[0099] S12: In step S12, set Xd = 0, and then proceed to step S13;

[0100] S13: In step S13, calculate the value of X, where X = Xi + Xd + Xe, and then proceed to step S14;

[0101] S14: In step S14, according to the environment where the air conditioner is located, read the target preset frequency Ft of the compressor under the environmental conditions preset by the air conditioner manufacturer, and then proceed to step S15;

[0102] S15: In step S15, determine whether the value of X is equal to 0. If X = 0, then proceed to step S16; otherwise, proceed to step S18;

[0103] S16: In step S16, the target operating frequency Ft' of the air conditioner is the same as the target preset frequency Ft of the compressor, that is, Ft' = Ft, and the air conditioner is set to operate in the normal mode;

[0104] S17: In step S17, determine whether the air conditioner has received a shutdown signal. If the air conditioner has received a shutdown signal, then proceed to step S27; otherwise, return to step S1;

[0105] S18: In step S18, the air conditioner is set to operate in the pre-frequency-down operation mode. Read the data of △F and β according to the value of X and the value of e, and then proceed to step S19;

[0106] S19: In step S19, the target operating frequency Ft' of the air conditioner is set as Ft' = Ft - β△F, and then proceed to step S20;

[0107] S20: In step S20, determine whether the air conditioner has received a shutdown signal. If the air conditioner has received a shutdown signal, then proceed to step S27; otherwise, proceed to step S21;

[0108] S21: In step S21, count the operating time t, and then proceed to step S22;

[0109] S22: In step S22, determine whether the operating time t is greater than the preset threshold f. If t ≥ f, then proceed to step S23; otherwise, return to step S20;

[0110] S23: In step S23, it is judged whether Td and Te are stable and meet the frequency increase condition. If Td and Te are stable and meet the frequency increase condition, then step S24 is entered; otherwise, step S25 is entered.

[0111] S24: In step S24, it is judged whether the value of e is equal to 3. If e = 3, then step S25 is entered; otherwise, step S26 is entered.

[0112] S25: In step S25, the statistical data of the running time t is cleared, and then step S2 is entered.

[0113] S26: In step S26, the value of e is incremented by 1, that is, e = e + 1, and then step S25 is entered.

[0114] S27: In step S27, the air conditioner is shut down, and then step S28 is entered.

[0115] S28: In step S28, the heating operation ends.

[0116] Symbol explanations in the above control logic steps:

[0117] To - Outdoor ambient temperature.

[0118] Ti - Indoor ambient temperature.

[0119] Td - Compressor discharge temperature.

[0120] Tc - Outdoor heat exchanger temperature.

[0121] Te - Indoor heat exchanger temperature.

[0122] △Td - Compressor discharge temperature change rate, such as the temperature change rate in the most recent 1 minute, unit: °C / min.

[0123] △Tc - Outdoor heat exchanger temperature change rate, such as the temperature change rate in the most recent 1 minute, unit: °C / min.

[0124] △Te - Indoor heat exchanger temperature change rate, such as the temperature change rate in the most recent 1 minute, unit: °C / min.

[0125] a - Refrigeration temperature determination threshold, unit: °C, such as 40 °C.

[0126] b - Heating temperature determination threshold, unit: °C, such as 25 °C.

[0127] c - Heat exchanger temperature change rate determination parameter, unit: °C / min, such as 3 °C / min.

[0128] d——Determination parameter for the rate of change of the exhaust gas temperature, unit: °C / min, such as 5 °C / min.

[0129] e——Revision number parameter for the correction value of the operating frequency. Here, the maximum value of e is defined as 3, that is, the value of e is 0, 1, 2, or 3.

[0130] f——Time statistical threshold, such as 5 min;

[0131] X——Statistical parameter for the pre-frequency reduction operation mode. The value of X is 0, 1, 2, or 3; X = 0 is the normal operation mode, X = 1 is the pre-frequency reduction operation mode 1, X = 2 is the pre-frequency reduction operation mode 2, and X = 3 is the pre-frequency reduction operation mode 3. During the refrigeration operation process, X = Xo + Xd + Xc; during the heating operation process, X = Xi + Xd + Xe;

[0132] Xo——Pre-frequency reduction mark for the outdoor ambient temperature. The value of Xo is 0 or 1.

[0133] Xi——Pre-frequency reduction mark for the indoor ambient temperature. The value of Xi is 0 or 1.

[0134] Xd——Pre-frequency reduction mark for the compressor exhaust gas temperature. The value of Xd is 0 or 1.

[0135] Xc——Pre-frequency reduction mark for the outdoor heat exchanger temperature. The value of Xc is 0 or 1.

[0136] Xe——Pre-frequency reduction mark for the indoor heat exchanger temperature. The value of Xe is 0 or 1.

[0137] Ft——Preset target operating frequency of the compressor.

[0138] t——Time statistical parameter.

[0139] △F——Correction value of the compressor target operating frequency.

[0140] α——Revision coefficient of the correction value of the compressor target operating frequency during the refrigeration operation process.

[0141] β——Revision coefficient of the correction value of the compressor target operating frequency during the heating operation process.

[0142] Ft’——Actual target operating frequency of the compressor.

[0143] In this specific embodiment, during the refrigeration operation process of the air conditioner, when the following situations are detected, effective pre-frequency reduction processing is performed on the operating frequency of the air conditioner compressor:

[0144] 1. The outdoor ambient temperature is too high;

[0145] 2. The compressor exhaust gas temperature rises too fast;

[0146] 3. The temperature of the outdoor heat exchanger rises too fast.

[0147] During the heating operation of the air conditioner, when the following situations are detected, effective processing of pre-reducing the operating frequency of the air conditioner compressor is carried out:

[0148] 1. The indoor ambient temperature is too high;

[0149] 2. The exhaust temperature of the compressor rises too fast;

[0150] 3. The temperature of the indoor heat exchanger rises too fast. Embodiment 2:

[0151] As Figure 1 shown, an air conditioner is applied to the high-temperature operation control method in Embodiment 1.

[0152] In the description of this specification, the description with reference to terms such as "one embodiment", "some embodiments", "example", "specific example", or "some examples" means that the specific features, structures, materials, or characteristics described in connection with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials, or characteristics described can be combined in any one or more embodiments or examples in a suitable manner.

[0153] Although the embodiments of the present invention have been shown and described above, it can be understood that the above embodiments are exemplary and should not be construed as limiting the present invention. Those of ordinary skill in the art can make changes, modifications, substitutions, and variations to the above embodiments within the scope of the present invention without departing from the principles and purposes of the present invention.

Claims

1. A high-temperature operation control method for an air conditioner, which is applied to the air conditioner. The air conditioner includes a controller, an indoor unit (10) and an outdoor unit (20); the indoor unit (10) includes an indoor heat exchanger (101), an indoor ambient temperature sensor (102), an indoor heat exchanger temperature sensor (103) and an indoor fan (104); the outdoor unit (20) includes a compressor (201), a four-way reversing valve (202), an outdoor heat exchanger (203), an outdoor ambient temperature sensor (204), an outdoor heat exchanger temperature sensor (205), an outdoor fan (207), an outdoor throttling mechanism (206) for controlling the flow rate, and an exhaust temperature sensor (208) for detecting the temperature of the refrigerant discharged by the compressor (201); the indoor heat exchanger (101) and the outdoor heat exchanger (203) form a loop through a first refrigerant connection pipe (30) and a second refrigerant connection pipe (40), the compressor (201) and the outdoor throttling mechanism (206) are arranged in the above loop, and the four-way reversing valve (202) is used to switch the valve ports so that the air conditioner has a cooling mode and a heating mode; characterized in that: The control method is as follows: In the cooling mode: Step 1: The air conditioner is turned on, and the cooling mode is turned on. The controller obtains the outdoor ambient temperature To and determines whether To is within the preset threshold a. If so, the outdoor ambient temperature pre-frequency reduction processing mark Xo = 0 is displayed on the controller; if not, the outdoor ambient temperature pre-frequency reduction processing mark Xo = 1 is displayed on the controller; Step 2: The controller obtains the outdoor heat exchanger temperature Tc and the compressor discharge temperature Td, and calculates the compressor discharge temperature change rate △Td and the outdoor heat exchanger temperature change rate △Tc per unit time. The controller determines whether △Tc is within the preset threshold c. If so, the outdoor ambient temperature pre-frequency reduction processing mark Xc = 0 is displayed on the controller; if not, the outdoor ambient temperature pre-frequency reduction processing mark Xc = 1 is displayed on the controller. The controller determines whether △Td is within the preset threshold d. If so, the outdoor ambient temperature pre-frequency reduction processing mark Xd = 0 is displayed on the controller; if not, the outdoor ambient temperature pre-frequency reduction processing mark Xd = 1 is displayed on the controller; Step 3: The controller calculates the value of parameter X, X = Xo + Xc + Xd, and reads the compressor target preset frequency Ft under the environmental conditions preset by the air conditioner manufacturer. The controller determines whether X is equal to 0. If it is equal to 0, the air conditioner target operating frequency Ft' is the same as the compressor target preset frequency Ft, and the air conditioner continues to operate in the normal mode or shuts down to end the cooling mode; If it is not equal to 0, the air conditioner operates in the pre-frequency reduction mode, and then enters Step 4; Step 4: Based on the value of parameter X, the controller reads the revision number parameter e of the preset compressor operating frequency correction value and the value of the compressor target operating frequency correction value △F; Based on the value of e, the controller reads the value of the revision coefficient α of the preset compressor target operating frequency correction value in the cooling mode; The controller obtains the value of the air conditioner target operating frequency Ft' under the environmental conditions through the calculation formula Ft' = Ft - α△F and adjusts the operating frequency of the compressor to Ft'; After the compressor operating frequency is adjusted, if the air conditioner continues to operate, it enters Step 5; if the air conditioner shuts down, the cooling mode ends; Step 5: The operating time t is counted. The controller determines whether the operating time t is greater than the preset threshold f. If t ≥ f, the controller determines whether Td and Te are stable and meet the frequency increase conditions. If Td and Te are stable and meet the frequency increase conditions, it is determined whether the value of e is equal to 3. If e = 3, the statistical data of the operating time t is cleared, and it enters Step 1; If e is not equal to 3, the revision number of the compressor operating frequency correction value is increased by one, that is, e = e + 1, the statistical data of the operating time t is cleared, and it enters Step 1; In the heating mode: Step 1: The air conditioner is turned on, and the heating mode is turned on. The controller obtains the indoor ambient temperature Ti and determines whether Ti is within the preset threshold b. If so, the indoor ambient temperature pre-frequency reduction processing mark Xi = 0 is displayed on the controller; if not, the indoor ambient temperature pre-frequency reduction processing mark Xi = 1 is displayed on the controller; Step 2: The controller obtains the indoor heat exchanger temperature Te and the compressor discharge temperature Td, and calculates the change rate of the compressor discharge temperature △Td and the change rate of the indoor heat exchanger temperature △Te per unit time; the controller determines whether △Te is within the preset threshold c. If so, the indoor environment temperature pre-frequency reduction processing mark Xe = 0 is displayed on the controller; if not, the indoor environment temperature pre-frequency reduction processing mark Xe = 1 is displayed on the controller; the controller determines whether △Td is within the preset threshold d. If so, the indoor environment temperature pre-frequency reduction processing mark Xd = 0 is displayed on the controller; if not, the indoor environment temperature pre-frequency reduction processing mark Xd = 1 is displayed on the controller. Step 3: The controller calculates the value of parameter X, X = Xi + Xe + Xd, and reads the compressor target preset frequency Ft under the environmental conditions preset by the air conditioner manufacturer; the controller determines whether X is equal to 0. If it is equal to 0, the air conditioner target operating frequency Ft' is the same as the compressor target preset frequency Ft, and the air conditioner continues to operate in the normal mode or shuts down to end the heating mode; if it is not equal to 0, the air conditioner operates in the pre-frequency reduction mode, and then enters Step 4. Step 4: Based on the value of parameter X, the controller reads the revision times parameter e of the preset compressor operating frequency correction value and the value of the compressor target operating frequency correction value △F. Based on the value of e, the controller reads the value of the revision coefficient β of the preset compressor target operating frequency correction value in the heating mode. The controller obtains the value of the air conditioner target operating frequency Ft' under the environmental conditions through the calculation formula Ft' = Ft - β△F and adjusts the operating frequency of the compressor to Ft'. After the compressor operating frequency is adjusted, if the air conditioner continues to operate, then enter Step 5; if the air conditioner shuts down, the cooling mode ends. Step 5: Statistic the operation time t, and the controller determines whether the operation time t is greater than the preset threshold f. If t ≥ f, the controller determines whether Td and Te are stable and meet the frequency increase conditions. If Td and Te are stable and meet the frequency increase conditions, it is determined whether the value of e is equal to 3. If e = 3, clear the statistical data of the operation time t and enter Step 1. If e is not equal to 3, then increase the revision times of the compressor operating frequency correction value by one, that is, e = e + 1, clear the statistical data of the operation time t, and enter Step 1.

2. The high-temperature operation control method of an air conditioner according to claim 1, wherein: When the cooling or heating mode is turned on, the data of parameters X, t, and e are reset to zero.

3. The high-temperature operation control method of an air conditioner according to claim 2, characterized in that: X is a statistical parameter for the pre-frequency reduction operation mode, and the value of X is 0, 1, 2, 3; X = 0 is the normal operation mode, X = 1 is the pre-frequency reduction operation mode 1, X = 2 is the pre-frequency reduction operation mode 2, and X = 3 is the pre-frequency reduction operation mode 3.

4. The high-temperature operation control method of an air conditioner according to claim 3, wherein: When the value of X is 1, 2, 3, the corresponding values of △F are 10, 15, 20; when the value of e is 0, 1, 2, 3, the corresponding values of α are 1, 0.8, 0.5, 0.2, and the corresponding values of β are 1, 0.7, 0.5, 0.

3.

5. The high-temperature operation control method of an air conditioner according to claim 1, characterized in that: The controller includes an indoor control mechanism (105) and an outdoor control mechanism (209) that can communicate with each other and control the indoor unit (10) and the outdoor unit (20) respectively.

6. An air conditioner, characterized in that: A high-temperature operation control method applied to an air conditioner according to any one of the above claims 1 to 5.

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