Air conditioner and defrosting control method thereof

Abstract

The invention discloses an air conditioner (1000) and a defrosting control method thereof. The air conditioner (1000) comprises an indoor unit (10), an outdoor unit (20) and a controller (40). The outdoor unit (20) comprises a compressor (201), an outdoor heat exchanger (202) and a first temperature sensor (207). The controller (40) is configured to: obtain operating parameters of the air conditioner (1000) when the air conditioner (1000) is in a heating mode; controlling the air conditioner (1000) to enter a false defrosting mode according to the operating parameters; determining a first frequency, an initial temperature difference and a second frequency; and according to the first frequency, the initial temperature difference and the second frequency, the air conditioner (1000) is controlled to operate for a preset duration in the false defrosting mode, and after the duration of operation of the air conditioner (1000) in the false defrosting mode exceeds the preset duration, the air conditioner (1000) is controlled to exit from the false defrosting mode.

Description

Air conditioner and defrost control method thereof

[0001] This application claims priority to the Chinese patent application with application number 202210763502.4 filed on June 30, 2022; priority to the Chinese patent application with application number 202210760685.4 filed on June 30, 2022, the entire contents of which are incorporated by reference into this application. Technical Field

[0002] The present disclosure relates to the technical field of air conditioning, and in particular to an air conditioner and a defrosting control method thereof. Background Art

[0003] With technological advancements and improved living standards, air conditioners have become a common necessity in our daily lives. In winter, when outdoor temperatures are low, air conditioners can operate in heating mode to provide indoor warmth. However, due to the low outdoor temperatures in winter, frost can form on the outdoor side of the air conditioner after prolonged operation in heating mode.

[0004] Summary of the Invention

[0005] In one aspect, an air conditioner is provided. The air conditioner includes an indoor unit, an outdoor unit, and a controller. The outdoor unit includes a compressor, an outdoor heat exchanger, and a first temperature sensor. The first temperature sensor is disposed on the outdoor heat exchanger and is configured to detect an outdoor ambient temperature. The controller is configured to: when the air conditioner is in the heating mode, obtain the operating parameters of the air conditioner; control the air conditioner to enter the false defrost mode according to the operating parameters, determine that the operating frequency of the compressor when the air conditioner enters the false defrost mode is a first frequency, and the outdoor temperature difference when the air conditioner enters the false defrost mode is an initial temperature difference, control the air conditioner to continue heating instead of defrosting, the outdoor temperature difference being the difference between the outdoor ambient temperature and the temperature of the coil in the outdoor heat exchanger; if it is determined that the operating frequency of the compressor remains unchanged for at least two consecutive preset cycles, determine that the operating frequency of the compressor at the current moment is a second frequency; according to the first frequency, the initial temperature difference and the second frequency, control the air conditioner to operate in the false defrost mode for a preset time, and control the air conditioner to exit the false defrost mode after the time for which the air conditioner operates in the false defrost mode exceeds the preset time.

[0006] In another aspect, a defrost control method for an air conditioner is provided. The defrost control method is applied to a controller of the air conditioner. The air conditioner includes an indoor unit and an outdoor unit. The outdoor unit includes a compressor, an outdoor heat exchanger, and a first temperature sensor. The first temperature sensor is disposed on the outdoor heat exchanger and is configured to detect an outdoor ambient temperature. The method includes: when the air conditioner is in a heating mode, obtaining operating parameters of the air conditioner; controlling the air conditioner to enter a pseudo-defrost mode according to the operating parameters; determining that the operating frequency of the compressor when the air conditioner enters the pseudo-defrost mode is a first frequency, and the outdoor temperature difference when the air conditioner enters the pseudo-defrost mode is an initial temperature difference, and controlling the air conditioner to continue heating instead of defrosting, the outdoor temperature difference being the difference between the outdoor ambient temperature and the temperature of the coil in the outdoor heat exchanger; if it is determined that the operating frequency of the compressor remains unchanged for at least two consecutive preset cycles, determining that the operating frequency of the compressor at the current moment is a second frequency; according to the first frequency, the initial temperature difference and the second frequency, controlling the air conditioner to operate in the pseudo-defrost mode for a preset time, and controlling the air conditioner to exit the pseudo-defrost mode after the time for which the air conditioner operates in the pseudo-defrost mode exceeds the preset time. BRIEF DESCRIPTION OF THE DRAWINGS

[0007] To more clearly illustrate the technical solutions of the present disclosure, the following briefly introduces the drawings required for use in some embodiments of the present disclosure. However, the drawings described below are only drawings of some embodiments of the present disclosure, and those skilled in the art can also derive other drawings based on these drawings. In addition, the drawings described below can be regarded as schematic diagrams and are not intended to limit the actual size of the products involved in the embodiments of the present disclosure, the actual process of the method, the actual timing of the signals, etc.

[0008] FIG1 is a structural diagram of an air conditioner according to some embodiments;

[0009] FIG2 is another structural diagram of an air conditioner according to some embodiments;

[0010] FIG3 is a block diagram of an air conditioner according to some embodiments;

[0011] FIG4 is a flow chart of steps performed by a controller in an air conditioner according to some embodiments;

[0012] FIG5 is a schematic diagram illustrating a correspondence between an operating frequency of a compressor and a third temperature according to some embodiments;

[0013] FIG6 is another flow chart of steps performed by a controller in an air conditioner according to some embodiments;

[0014] FIG7 is another flow chart of steps performed by a controller in an air conditioner according to some embodiments;

[0015] FIG8 is another flow chart of steps performed by a controller in an air conditioner according to some embodiments;

[0016] FIG9 is another flow chart of steps performed by a controller in an air conditioner according to some embodiments;

[0017] FIG10 is another flow chart of steps performed by a controller in an air conditioner according to some embodiments;

[0018] FIG11 is another flow chart of steps performed by a controller in an air conditioner according to some embodiments;

[0019] FIG12 is another flow chart of steps performed by a controller in an air conditioner according to some embodiments;

[0020] FIG13 is another flow chart of steps performed by a controller in an air conditioner according to some embodiments;

[0021] 14 is yet another flow chart of steps performed by a controller in an air conditioner according to some embodiments. DETAILED DESCRIPTION

[0022] The following will be combined with the accompanying drawings to clearly and completely describe some embodiments of the present disclosure. Obviously, the embodiments described are only some embodiments of the present disclosure, not all embodiments. Based on the embodiments provided by the present disclosure, all other embodiments obtained by ordinary technicians in this field are within the scope of protection of the present disclosure.

[0023] Unless the context requires otherwise, throughout the specification and claims, the term "comprise" and its other forms, such as the third person singular form "comprises" and the present participle form "comprising", are to be interpreted as open and inclusive, that is, "including, but not limited to". In the description of the specification, the terms "one embodiment", "some embodiments", "exemplary embodiments", "example", "specific example" or "some examples" are intended to indicate that the particular features, structures, materials or characteristics associated with the embodiment or example are included in at least one embodiment or example of the present disclosure. The schematic representation of the above terms does not necessarily refer to the same embodiment or example. In addition, the particular features, structures, materials or characteristics may be included in any one or more embodiments or examples in any appropriate manner.

[0024] In the following, the terms "first" and "second" are used for descriptive purposes only and should not be understood to indicate or imply relative importance or implicitly specify the number of the technical features indicated. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include one or more of the features. In the description of the embodiments of the present disclosure, unless otherwise specified, "plurality" means two or more.

[0025] When describing some embodiments, the expressions "coupled" and "connected" and their derivatives may be used. The term "connected" should be understood in a broad sense. For example, "connection" can be a fixed connection, a detachable connection, or an integral connection; it can be directly connected or indirectly connected through an intermediate medium. The term "coupled" indicates that two or more components are in direct physical or electrical contact. The term "coupled" or "communicatively coupled" may also refer to two or more components that are not in direct contact with each other, but still cooperate or interact with each other. The embodiments disclosed herein are not necessarily limited to the contents of this document.

[0026] “A and / or B” includes the following three combinations: A only, B only, and a combination of A and B.

[0027] As used herein, the term "if" is optionally interpreted to mean "when" or "upon" or "in response to determining" or "in response to detecting," depending on the context. Similarly, the phrases "if it is determined that" or "if [stated condition or event] is detected" are optionally interpreted to mean "upon determining" or "in response to determining" or "upon detecting [stated condition or event]" or "in response to detecting [stated condition or event]," depending on the context.

[0028] The use of "adapted to" or "configured to" herein is intended to be open and inclusive language that does not exclude devices adapted or configured to perform additional tasks or steps.

[0029] As used herein, "about," "substantially," or "approximately" includes the stated value and an average value that is within an acceptable range of deviation from the particular value as determined by one of ordinary skill in the art taking into account the measurements in question and the errors associated with the measurement of the particular quantity (i.e., the limitations of the measurement system).

[0030] As used herein, "parallel," "perpendicular," and "equal" include the stated conditions and conditions approximating the stated conditions within an acceptable range of deviation as determined by one of ordinary skill in the art taking into account the measurement in question and the errors associated with the measurement of the particular quantity (i.e., the limitations of the measurement system).

[0031] When the outdoor unit of an air conditioner is frosted, the frost layer increases the thermal resistance of the outdoor unit, reduces the outdoor air circulation area, increases the flow resistance, reduces the air volume of the outdoor unit, and thus reduces the heat exchange effect of the outdoor unit. Therefore, the air conditioner needs to be defrosted after running for a period of time.

[0032] The current defrosting methods mainly include reverse cycle defrosting, hot gas bypass defrosting and phase change energy storage defrosting. When the air conditioner adopts the reverse cycle defrosting method, the indoor heat exchanger acts as an evaporator, which will cause the indoor ambient temperature to drop, affecting the heating effect of the air conditioner. When the air conditioner adopts the hot gas bypass defrosting method, by setting a bypass loop at the exhaust port of the compressor, the high-temperature gaseous refrigerant discharged from the compressor can be diverted to the outdoor heat exchanger to achieve defrosting. However, the hot gas bypass defrosting method requires a longer time, usually more than twice the reverse cycle defrosting time. The phase change energy storage defrosting method refers to storing part of the heat in the heat accumulator in the heating mode, and releasing the heat during defrosting for defrosting. However, phase change energy storage defrosting will affect the heat dissipation of the compressor, which can easily cause the exhaust temperature of the compressor to be too high, and the energy storage of the heat accumulator is limited.

[0033] Generally, the difference between the outdoor ambient temperature and the coil temperature in the outdoor heat exchanger can be used to determine whether to defrost the air conditioner. However, in some scenarios, for example, when the indoor temperature difference increases, or the air conditioner changes from silent or low wind mode to high wind mode, or the air conditioner changes from sleep or silent mode to heating mode, the operating frequency of the compressor suddenly increases, causing the coil temperature of the outdoor heat exchanger to drop, thereby increasing the difference between the outdoor ambient temperature and the coil temperature of the outdoor heat exchanger, and the air conditioner needs to defrost the outdoor heat exchanger. However, at this time, there may be no frost or less frost on the outdoor heat exchanger, and defrosting the air conditioner will cause large fluctuations in the indoor temperature, affecting the heating effect of the air conditioner and consuming energy. It should be noted that in the silent, low wind, and sleep modes, the operating frequency of the compressor in the air conditioner is relatively low.

[0034] For example, in silent mode, the air conditioner's indoor fan speed and compressor operating frequency are lowered to reduce noise and achieve a quieter effect. In sleep mode, the indoor ambient temperature is gradually lowered by gradually lowering the set temperature, simulating the natural regulation of body temperature at night, thereby achieving energy savings while providing a comfortable sleeping environment. Low airflow mode is typically used when the indoor ambient temperature meets the required level but air flow is still required. In this mode, the air conditioner reduces the indoor air flow by lowering the air volume supplied by the indoor unit, thereby reducing air flow and achieving energy savings.

[0035] In order to solve the above problems, some embodiments of the present disclosure provide an air conditioner 1000 .

[0036] FIG. 1 is a structural diagram of an air conditioner according to some embodiments.

[0037] In some embodiments, as shown in Fig. 1, an air conditioner 1000 includes an indoor unit 10 and an outdoor unit 20. The indoor unit 10 and the outdoor unit 20 are connected by a pipeline to transmit refrigerant.

[0038] It should be noted that FIG1 illustrates an example in which the air conditioner 1000 is a wall-mounted air conditioner, with the indoor unit 10 mounted on an indoor wall. Of course, the air conditioner 1000 in some embodiments of the present disclosure may also be a floor-standing air conditioner. Furthermore, since the indoor unit 10 in FIG1 is located indoors and the outdoor unit 20 is located outdoors, the outdoor unit 20 is represented by a dotted line in FIG1 .

[0039] FIG. 2 is another structural diagram of an air conditioner according to some embodiments.

[0040] In some embodiments, as shown in FIG2 , the indoor unit 10 includes an indoor heat exchanger 101 and an indoor fan 102. The outdoor unit 20 includes a compressor 201, an outdoor heat exchanger 202, an outdoor fan 203, an expansion valve 204, and a four-way valve 205. The compressor 201, the outdoor heat exchanger 202, the expansion valve 204, and the indoor heat exchanger 101, connected in sequence, form a refrigerant circuit. Refrigerant circulates in this refrigerant circuit and exchanges heat with air through the outdoor heat exchanger 202 and the indoor heat exchanger 101, respectively, to achieve cooling mode or heating mode for the air conditioner 1000.

[0041] The compressor 201 is configured to compress the refrigerant so that the low-pressure refrigerant is compressed to form a high-pressure refrigerant.

[0042] The outdoor heat exchanger 202 is configured to exchange heat between outdoor air and the refrigerant transmitted through the outdoor heat exchanger 202. For example, in the cooling mode of the air conditioner 1000, the outdoor heat exchanger 202 operates as a condenser, causing the refrigerant compressed by the compressor 201 to condense by dissipating heat to the outdoor air through the outdoor heat exchanger 202. In the heating mode of the air conditioner 1000, the outdoor heat exchanger 202 operates as an evaporator, causing the decompressed refrigerant to absorb heat from the outdoor air through the outdoor heat exchanger 202 and evaporate. The outdoor heat exchanger 202 is provided with a coil connected to the refrigerant circuit. The refrigerant flows through the coil of the outdoor heat exchanger 202 to exchange heat with the outdoor air.

[0043] The outdoor fan 203 is configured to draw outdoor air into the outdoor unit 20 through the outdoor air inlet of the outdoor unit 20 and to deliver the outdoor air, after heat exchange with the outdoor heat exchanger 202, through the outdoor air outlet of the outdoor unit 20. The outdoor fan 203 provides power for the flow of outdoor air, so that the outdoor air flows through the outdoor heat exchanger 202 and exchanges heat with the refrigerant in the outdoor heat exchanger 202.

[0044] The expansion valve 204 is connected between the outdoor heat exchanger 202 and the indoor heat exchanger 101. The opening of the expansion valve 204 regulates the pressure of the refrigerant flowing through the outdoor heat exchanger 202 and the indoor heat exchanger 101, thereby adjusting the refrigerant flow rate between the outdoor heat exchanger 202 and the indoor heat exchanger 101. The flow rate and pressure of the refrigerant flowing between the outdoor heat exchanger 202 and the indoor heat exchanger 101 will affect the heat exchange performance of the outdoor heat exchanger 202 and the indoor heat exchanger 101. The opening of the expansion valve 204 is adjustable to control the flow rate and pressure of the refrigerant flowing through the expansion valve 204. For example, the expansion valve 204 expands the liquid refrigerant condensed in the condenser into a low-pressure liquid refrigerant. It should be noted that some embodiments of the present disclosure use the expansion valve 204 as an example of being located in the outdoor unit 20. Of course, in some embodiments, the expansion valve 204 can also be located in the indoor unit 10.

[0045] The four-way valve 205 is connected to the refrigerant circuit and is configured to switch the flow direction of the refrigerant in the refrigerant circuit so that the air conditioner 1000 performs a cooling mode or a heating mode.

[0046] The indoor heat exchanger 101 is configured to exchange heat between the indoor air and the refrigerant flowing through the indoor heat exchanger 101. For example, in the cooling mode of the air conditioner 1000, the indoor heat exchanger 101 operates as an evaporator, causing the refrigerant, after dissipating heat through the outdoor heat exchanger 202, to absorb heat from the indoor air through the indoor heat exchanger 101 and evaporate. In the heating mode of the air conditioner 1000, the indoor heat exchanger 101 operates as a condenser, causing the refrigerant, after absorbing heat from the outdoor heat exchanger 202, to dissipate heat to the indoor air through the indoor heat exchanger 101 and condense. The indoor heat exchanger 101 is equipped with a coil connected to the refrigerant circuit. The refrigerant flows through the coil of the indoor heat exchanger 101 to exchange heat with the indoor air.

[0047] The indoor fan 102 is configured to draw indoor air into the indoor unit 10 through the indoor air inlet of the indoor unit 10 and send the indoor air after heat exchange with the indoor heat exchanger 101 out through the indoor air outlet of the indoor unit 10. The indoor fan 102 provides power for the flow of indoor air.

[0048] FIG3 is a block diagram of an air conditioner according to some embodiments.

[0049] In some embodiments, as shown in FIG3 , the air conditioner 1000 further includes a controller 40. The controller 40 is configured to control the operation of various components within the air conditioner 1000 to implement various predetermined functions of the air conditioner 1000. For example, the controller 40 controls the operating frequency of the compressor 201, the opening degree of the expansion valve 204, and the speed S of the indoor fan 102. Furthermore, the controller 40 is connected to the compressor 201, the expansion valve 204, the outdoor fan 203, and the indoor fan 102 via data cables for communication information transmission.

[0050] In some embodiments, as shown in FIG2 , the controller 40 includes a first sub-controller 401 and a second sub-controller 402. The first sub-controller 401 is located in the indoor unit 10, and the second sub-controller 402 is located in the outdoor unit 20. Furthermore, the first sub-controller 401 and the second sub-controller 402 are connected via a signal line and can send and receive signals to each other. It should be noted that the first sub-controller 401 and the second sub-controller 402 can also be the same controller, and this disclosure is not limited to this.

[0051] The controller 40 includes a processor. The processor may include a central processing unit (CPU), a microprocessor (microprocessor), or an application specific integrated circuit (ASIC), and may be configured to perform the corresponding operations described in the controller 40 when the processor executes a program stored in a non-transitory computer-readable medium coupled to the controller 40.

[0052] In some embodiments, as shown in FIG. 1 , the air conditioner 1000 further includes a remote controller 30 , which is configured to communicate with the controller 40 to enable interaction between the user and the air conditioner 1000 .

[0053] In some embodiments, as shown in Figures 2 and 3, the outdoor unit 20 further includes a first temperature sensor 207 and a third temperature sensor 206. The first temperature sensor 207 is disposed on the outdoor heat exchanger 202 and is configured to detect the outdoor ambient temperature (i.e., the first temperature T1). The third temperature sensor 206 is disposed on the coil of the outdoor heat exchanger 202 and is configured to detect a third temperature T3 of the coil within the outdoor heat exchanger 202. The controller 40 is coupled to the first temperature sensor 207 and the third temperature sensor 206 to receive the outdoor ambient temperature detected by the first temperature sensor 207 and the temperature of the coil within the outdoor heat exchanger 202 detected by the third temperature sensor 206.

[0054] In some embodiments, as shown in Figures 2 and 3, the indoor unit 10 further includes a second temperature sensor 104 and a fourth temperature sensor 103. The second temperature sensor 104 is disposed on the indoor heat exchanger 101 and is configured to detect the indoor ambient temperature (i.e., the second temperature T2). The fourth temperature sensor 103 is disposed on the coil of the indoor heat exchanger 101 and is configured to detect a fourth temperature T4 of the coil within the indoor heat exchanger 101. The controller 40 is coupled to the second temperature sensor 104 and the fourth temperature sensor 103 to receive the temperature of the coil within the indoor heat exchanger 101 detected by the fourth temperature sensor 103, as well as the indoor ambient temperature detected by the second temperature sensor 104.

[0055] Generally, the air conditioner 1000 can operate in a cooling mode, a heating mode, and a defrosting mode.

[0056] When air conditioner 1000 is operating in cooling mode, the refrigerant flows sequentially through compressor 201, four-way valve 205, outdoor heat exchanger 202, expansion valve 204, indoor heat exchanger 101, and compressor 201. Outdoor heat exchanger 202 acts as a condenser, and indoor heat exchanger 101 acts as an evaporator. The condenser dissipates heat from the refrigerant inside to the outdoor air, while the refrigerant in the evaporator absorbs heat from the indoor air, lowering the indoor temperature and cooling the indoor environment.

[0057] When air conditioner 1000 is operating in heating mode, the refrigerant flows sequentially through compressor 201, four-way valve 205, indoor heat exchanger 101, expansion valve 204, outdoor heat exchanger 202, and compressor 201. Indoor heat exchanger 101 acts as a condenser, and outdoor heat exchanger 202 acts as an evaporator. The condenser dissipates heat from the refrigerant inside it into the indoor air, raising the indoor temperature and heating the indoor environment. The refrigerant in the evaporator absorbs heat from the outdoor air.

[0058] For the air conditioner 1000 that adopts the reverse cycle defrosting method for defrosting, when the air conditioner 1000 operates in the defrosting mode, the flow direction of the refrigerant is the same as the flow direction of the refrigerant when the air conditioner 1000 operates in the cooling mode.

[0059] The following describes in detail the steps performed by the controller 40 in some embodiments of the present disclosure.

[0060] FIG4 is a flow chart of steps performed by a controller in an air conditioner according to some embodiments.

[0061] In some embodiments, as shown in FIG. 4 , the controller 40 is configured to perform steps 11 to 15 .

[0062] In step 11, when the air conditioner 1000 is in the heating mode, the operating frequency F of the compressor 201 is obtained.

[0063] For example, when the controller 40 receives a heating signal (e.g., a heating signal sent by the remote controller 30), the controller 40 controls the operating status of the corresponding components in the air conditioner 1000 to perform heating. In this case, the controller 40 can determine that the air conditioner 1000 is in the heating mode. The controller 40 can obtain the current or voltage curve of the compressor 201 through a current or voltage sensor, and then calculate the operating frequency F of the compressor 201 based on the current or voltage curve. Of course, the method of determining that the air conditioner 1000 is in the heating mode and obtaining the operating frequency F of the compressor 201 is not limited to this, and the present disclosure does not limit this.

[0064] After the air conditioner 1000 has been running for a period of time, the air conditioner 1000 reaches a stable state, and the operating frequency F of the compressor 201 stabilizes. When the air conditioner 1000 is operating in heating mode, when the indoor ambient temperature decreases, or when the air conditioner 1000 changes from silent or low fan mode to high fan mode, or when the air conditioner changes from sleep or silent mode to heating mode, the operating frequency F of the compressor 201 increases.

[0065] In step 12, it is determined that within the preset period G, the increase value ΔF of the operating frequency F of the compressor 201 is greater than the preset frequency threshold A, and the air conditioner 1000 is controlled to enter the false defrost mode.

[0066] When the air conditioner 1000 is operating in the false defrost mode, the controller 40 controls the air conditioner 1000 to heat and not to defrost. When the operating frequency F of the compressor 201 suddenly increases, the refrigerant flow rate is insufficient for a short period of time, causing the pressure of the evaporator (e.g., the outdoor heat exchanger 202) to drop, which in turn causes the third temperature T3 of the coil of the outdoor heat exchanger 202 to drop suddenly.

[0067] FIG5 is a schematic diagram illustrating a correspondence between an operating frequency of a compressor and a third temperature according to some embodiments.

[0068] For example, as shown in FIG5 , line M represents the change of the operating frequency F of the compressor 201 over time, line N represents the first change of the third temperature T3 over time, and line Q represents the second change of the third temperature T3 over time.

[0069] 5 , during the period from the first moment t1 to the second moment t2, the operating frequency F of the compressor 201 suddenly increases from the first sub-frequency Fm1 to the second sub-frequency Fm2. After the second moment t2, the operating frequency F of the compressor 201 remains unchanged.

[0070] As shown by line N in Figure 5 , starting at first time t1, the third temperature T3 decreases from the first sub-temperature T11 and drops to the second sub-temperature T12 at third time t3, at which point the third temperature T3 reaches its minimum value. In this case, the difference between the outdoor ambient temperature (first temperature T1) and the third temperature T3 (e.g., second sub-temperature T12) (i.e., first temperature difference ΔTm1) may satisfy the defrosting conditions for air conditioner 1000. However, the decrease in third temperature T3 is due to unstable operation of compressor 201, and in reality, there may be no frost or minimal frost on outdoor heat exchanger 202. If air conditioner 1000 operates in defrost mode, the second indoor ambient temperature T2 decreases, affecting the heating effect of air conditioner 1000. It should be noted that the first temperature difference ΔTm1 is the outdoor temperature difference (i.e., the difference between the outdoor ambient temperature and the temperature of the coil within outdoor heat exchanger 202).

[0071] Furthermore, as shown by lines N and Q in FIG. 5 , after the fifth moment t5, the third temperature T3 returns to a stable state and remains constant. Alternatively, as shown by line Q, the third temperature T3 rises to the fourth sub-temperature T23 after the fourth moment t4 and remains constant for a short period of time. In this case, if the difference between the outdoor ambient temperature (the first temperature T1) and the third temperature T3 (such as the third sub-temperature T13 or the fourth sub-temperature T23) does not meet the defrosting conditions of the air conditioner 1000, the air conditioner 1000 needs to exit the defrost mode and return to the heating mode. In this case, the air conditioner 1000 will only have a short defrosting time, which will not achieve the desired defrosting effect and will also consume energy.

[0072] In order to solve the above problem, a preset frequency threshold A and a preset period G are set in some embodiments of the present disclosure.

[0073] The preset frequency threshold value A is a preset threshold value. The preset period G is a preset time period for detecting the operating frequency F of the compressor 201 .

[0074] The increase value ΔF of the operating frequency F of the compressor 201 refers to the increase value of the operating frequency F of the compressor 201 within a preset period G. For example, the operating frequency F of the compressor 201 last acquired by the controller 40 is recorded as the first operating frequency F(r-1), and the operating frequency F of the compressor 201 currently acquired by the controller 40 is recorded as the second operating frequency F(r), where r≥1. In this case, the increase value ΔF of the operating frequency F of the compressor 201 is the difference between the second operating frequency F(r) and the first operating frequency F(r-1) (i.e., ΔF=F(r)-F(r-1)). If the increase value ΔF of the operating frequency F of the compressor 201 within the preset period G is greater than the preset frequency threshold A (i.e., ΔF>A), the controller 40 determines that the operating frequency F of the compressor 201 has increased rapidly within a short period of time. In this way, to prevent the air conditioner 1000 from erroneously performing defrosting, the controller 40 can control the air conditioner 1000 to enter a false defrost mode and then determine whether to control the air conditioner 1000 to enter the defrost mode.

[0075] When the air conditioner 1000 operates in defrost mode using a reverse cycle defrost method, the indoor heat exchanger 101 in the air conditioner 1000 operates as an evaporator, and the outdoor heat exchanger 202 in the air conditioner 1000 operates as a condenser. At this time, the outdoor heat exchanger 202 dissipates heat to melt the frost layer on the outdoor heat exchanger 202, thereby achieving defrost. Of course, the present disclosure may also employ other defrost methods (such as hot gas bypass defrost and phase change energy storage defrost).

[0076] In some embodiments, the preset frequency threshold A is greater than or equal to 3 Hz. For example, the preset frequency threshold A is 3 Hz, 4 Hz, 6 Hz, 8 Hz, or 10 Hz. When the air conditioner 1000 is running, the operating frequency F of the compressor 201 may vary slightly due to various reasons. If the preset frequency threshold A is set to a smaller value, the air conditioner 1000 may frequently enter the false defrost mode, affecting the normal operation of the air conditioner 1000. Therefore, the preset frequency threshold A can be set to be greater than a certain value. It should be noted that different preset frequency thresholds A can be set according to the configuration of the air conditioner 1000.

[0077] In some embodiments, the preset period G is greater than or equal to 1s and less than or equal to 1min (1s≤G≤1min). For example, the preset period G is 1s, 10s, 20s, 30s, 50s or 1min, etc. Since the duration of the sudden change in the operating frequency F of the compressor 201 is short, and the time for the air conditioner 1000 to be in an unstable state is short, the preset period G needs to be set to a smaller value to timely detect the changes in the operating frequency F of the compressor 201. In this way, through the preset period G, when the air conditioner 1000 is running in heating mode, the controller 40 can obtain the operating frequency F of the compressor 201 once every certain period of time. It should be noted that different preset periods G can be preset according to the configuration of the air conditioner 1000.

[0078] In step 13 , the operating frequency F of the compressor 201 when the air conditioner 1000 enters the false defrost mode is determined to be the first frequency Fr, the first temperature difference ΔTm1 is determined to be the initial temperature difference ΔTm11 , and the air conditioner 1000 is controlled to continue heating rather than defrosting.

[0079] When the operating frequency F of compressor 201 suddenly increases, third temperature T3 drops rapidly. In this case, the difference between first temperature T1 and third temperature T3 cannot reflect the actual frosting condition of outdoor heat exchanger 202. Therefore, controller 40 cannot accurately determine whether defrosting is necessary based on first temperature difference ΔTm1. If controller 40 determines that air conditioner 1000 is defrosting based on the drop in third temperature T3, controller 40 will make a misjudgment and air conditioner 1000 will mistakenly enter defrost mode. Therefore, in false defrost mode, even if controller 40 determines that third temperature T3 has dropped, controller 40 does not need to determine whether third temperature T3 meets the defrost conditions. In this case, controller 40 controls air conditioner 1000 to continue heating without defrosting, thereby preventing air conditioner 1000 from mistakenly entering defrost mode and affecting the heating effect of air conditioner 1000.

[0080] It should be noted that the process by which the controller 40 determines that the air conditioner 1000 enters the defrost mode is as follows: after the compressor 201 has been running for a period of time, the controller 40 obtains the first temperature T1 and the third temperature T3 through the first temperature sensor 207 and the third temperature sensor 206. When the controller 40 determines that the first temperature T1 is less than or equal to the first temperature threshold, the third temperature T3 is less than or equal to the second temperature threshold, and the first temperature difference ΔTm1 is greater than or equal to the third temperature threshold, the air conditioner 1000 runs the defrost mode. When the controller 40 detects that the third temperature T3 is greater than or equal to the fourth temperature threshold, the air conditioner 1000 exits the defrost mode. The first temperature threshold, the second temperature threshold, the third temperature threshold and the fourth temperature threshold are pre-set thresholds, which can be set according to actual needs, and the present disclosure does not impose any restrictions on this.

[0081] Since the first temperature difference ΔTm1 in the false defrost mode cannot indicate the frost condition of the outdoor unit 20, the controller 40 may not obtain the first temperature T1 after the air conditioner 1000 enters the false defrost mode. Alternatively, the controller 40 may directly set the first temperature T1 to a fixed value that is greater than the first temperature threshold. In this way, since the first temperature T1 does not meet the conditions for the air conditioner 1000 to enter the defrost mode in the false defrost mode, the air conditioner 1000 can be prevented from mistakenly entering the defrost mode.

[0082] In step 14 , when it is determined that the operating frequency F of the compressor 201 remains unchanged for at least two consecutive preset periods G, the operating frequency F of the compressor 201 at the current moment is determined to be the second frequency Fn.

[0083] After the air conditioner 1000 enters the false defrost mode, the changed operating frequency F of the compressor 201 remains stable after a period of time. Therefore, if the controller 40 determines that the operating frequency F of the compressor 201 remains unchanged for at least two consecutive preset cycles G, the controller 40 determines that the operating frequency F of the compressor 201 has stabilized and determines the operating frequency F of the compressor 201 at the current moment as the second frequency Fn. For example, when N is equal to 2, if the controller 40 determines that the operating frequency F of the compressor 201 remains unchanged for two consecutive preset cycles G, that is, if the controller 40 determines that the operating frequency F of the compressor 201 in the first preset cycle G remains unchanged and the operating frequency Fn(2) of the compressor 201 in the second preset cycle G is the same (Fn(1)=Fn(2)), the controller 40 determines the operating frequency Fr(2) of the compressor 201 at the current moment as the second frequency Fn.

[0084] It should be noted that the second frequency Fn is the operating frequency F of the compressor 201 that remains stable for a short period of time when the operation of the air conditioner 1000 is unstable. Since the second frequency Fn only indicates that the operating frequency F of the compressor 201 is stable for a short period of time, the controller 40 can only determine that the operating frequency F of the compressor 201 has entered a stable state when the operating frequency F of the compressor 201 remains unchanged for a period of time greater than a certain period, thereby further determining that the operation of the air conditioner 1000 is stable.

[0085] In step 15, based on the first frequency Fr, the initial temperature difference ΔTm11 and the second frequency Fn, the air conditioner 1000 is controlled to run in the false defrost mode for a preset time H, and after the time the air conditioner 1000 runs in the false defrost mode exceeds the preset time H, the air conditioner 1000 is controlled to exit the false defrost mode.

[0086] Since the lower the operating frequency F of the compressor 201, the smaller the refrigerant flow rate, the higher the temperature of the refrigerant when evaporating in the evaporator (e.g., the outdoor heat exchanger 202), and the higher the third temperature T3, the less likely the outdoor heat exchanger 202 is to frost. Therefore, different preset frequency ranges M can be set with the maximum operating frequency Fmax of the compressor 201 as the upper limit. The controller 40 then makes a judgment based on the first frequency Fr, the second frequency Fn, and the different preset frequency ranges M to determine the impact of the operating frequency F of the compressor 201 on frost formation on the outdoor heat exchanger 202 after the operating frequency F of the compressor 201 changes.

[0087] Because greater outdoor humidity leads to faster frost formation on outdoor heat exchanger 202, a faster decrease in third temperature T3, and a greater first temperature difference ΔTm1, the controller 40 can determine the impact of outdoor humidity on frost formation on outdoor heat exchanger 202 after a change in the operating frequency F of compressor 201 by comparing the initial temperature difference ΔTm11 with the preset temperature difference B when setting different preset frequency ranges M.

[0088] In addition, since the operating frequency F of the compressor 201 increases, the higher the increased operating frequency F, the longer it takes for the air conditioner 1000 to return to a stable state. Therefore, different preset time lengths H can be set according to different preset frequency ranges M.

[0089] For example, when the initial temperature difference ΔTm11 is greater than or equal to the preset temperature difference B, the outdoor humidity is high, frost forms quickly on the outdoor heat exchanger 202, and frost easily forms on the outdoor heat exchanger 202. In this case, the controller 40 controls the air conditioner 1000 to exit the false defrost mode and enter the heating mode, and determines whether the air conditioner 1000 should perform defrost. When the initial temperature difference ΔTm11 is less than the preset temperature difference B, the outdoor humidity is low, frost forms slowly on the outdoor heat exchanger 202, and there is no frost or little frost on the outdoor heat exchanger 202.

[0090] Furthermore, when compressor 201 operates at a medium or low frequency, the refrigerant flow rate is low, and the temperature of the refrigerant when evaporating in the evaporator (e.g., outdoor heat exchanger 202) is high, causing frost to form slowly or be difficult to form on outdoor heat exchanger 202. In this case, if the initial temperature difference ΔTm11 is less than the preset temperature difference B, there is no frost or only a small amount of frost on outdoor heat exchanger 202, and air conditioner 1000 does not need to perform defrosting.

[0091] In addition, if the controller 40 determines that the first frequency Fr and the second frequency Fn are medium or low frequencies, the possibility of frost forming on the outdoor heat exchanger 202 is low. The higher the preset frequency range M in which the second frequency Fn is located, the longer the time (e.g., the preset time H) that the controller 40 controls the air conditioner 1000 to operate in the false defrost mode.

[0092] It should be noted that if the controller 40 determines that the second frequency Fn is greater than the first frequency Fr, the controller 40 continues to determine the first frequency Fr, the second frequency Fn, and the initial temperature difference ΔTm11. If the controller 40 determines that the second frequency Fn is less than the first frequency Fr, the operating frequency F of the compressor 201 does not increase, and the controller 40 controls the air conditioner 1000 to exit the false defrost mode.

[0093] Therefore, in the case where the first temperature difference ΔTm1 changes due to a change in the operating frequency F of the compressor 201, causing the air conditioner 1000 to mistakenly enter the defrost mode, some embodiments of the present disclosure provide an air conditioner 1000. The controller 40 in the air conditioner 1000 controls the air conditioner 1000 to operate in the pseudo-defrost mode for a preset time period H without defrosting, based on the first frequency Fr, the initial temperature difference ΔTm11, and the second frequency Fn. This prevents the air conditioner 1000 from defrosting when there is no frost and from frequently defrosting. Then, after the air conditioner 1000 has operated in the pseudo-defrost mode for a period exceeding the preset time period H, the air conditioner 1000 returns to a stable state, and the controller 40 controls the air conditioner 1000 to exit the pseudo-defrost mode. Therefore, when frost forms on the outdoor heat exchanger 202, the controller 40 can promptly control the air conditioner 1000 to exit the pseudo-defrost mode and perform a defrost determination, thereby improving the heat exchange efficiency of the air conditioner 1000. In addition, by controlling the air conditioner 1000 to enter the pseudo-defrost mode, the operating stability of the air conditioner 1000 can be improved and energy consumption can be reduced.

[0094] In the air conditioner 1000 provided in some embodiments of the present disclosure, the controller 40 controls the air conditioner 1000 to operate in a pseudo-defrost mode for a preset duration H based on the preset frequency range M within which the first frequency Fr falls, the relationship between the initial temperature difference ΔTm11 and the preset temperature difference B, and the preset frequency range M within which the second frequency Fn falls. The controller 40 then controls the air conditioner 1000 to exit the pseudo-defrost mode after the air conditioner 1000 has operated in the pseudo-defrost mode for a duration exceeding the preset duration H. This prevents the air conditioner 1000 from defrosting when there is no frost and from frequently defrosting, thereby improving the operational stability of the air conditioner 1000 and reducing energy consumption. Furthermore, when frost forms on the outdoor heat exchanger 202, the controller 40 can promptly control the air conditioner 1000 to exit the pseudo-defrost mode, thereby improving the heat exchange efficiency of the air conditioner 1000.

[0095] 6 is another flow chart of steps performed by a controller in an air conditioner according to some embodiments.

[0096] In some embodiments, the preset frequency range M includes a first frequency range M1, a second frequency range M2, a third frequency range M3, and a fourth frequency range M4. The first frequency range M1 is greater than 0 Hz and less than or equal to the first preset frequency F1. The second frequency range M2 is greater than the first preset frequency F1 and less than or equal to the second preset frequency F2. The third frequency range M3 is greater than the second preset frequency F2 and less than or equal to the third preset frequency F3. The fourth frequency range M4 is greater than the third preset frequency F3 and less than or equal to the maximum operating frequency Fmax of the compressor 201. The first preset frequency F1 is less than the second preset frequency F2 (F1 < F2), and the second preset frequency F2 is less than the third preset frequency F3 (F2 < F3).

[0097] The preset temperature difference B includes a first preset temperature difference ΔTb1, a second preset temperature difference ΔTb2, and a third preset temperature difference ΔTb3. The preset time H can be set according to the configuration of the air conditioner 1000.

[0098] In this case, as shown in FIG. 6 , step 15 executed by the controller 40 includes steps 151 to 155 .

[0099] In step 151 , it is determined that the first frequency Fr is less than or equal to the first preset frequency F1 (Fr≤F1) and the initial temperature difference ΔTm11 is less than the first preset temperature difference ΔTb1 (ΔTm11<ΔTb1).

[0100] If the controller 40 determines that the first frequency Fr is less than or equal to the first preset frequency F1, then when the air conditioner 1000 enters the false defrost mode, the operating frequency F (first frequency Fr) of the compressor 201 is in the low frequency range, and frost forms slowly or is difficult to form on the outdoor heat exchanger 202.

[0101] In this case, if the controller 40 determines that the initial temperature difference △Tm11 is less than the first preset temperature difference △Tb1, then when the air conditioner 1000 enters the false defrost mode, the first temperature difference △Tm1 (initial temperature difference △Tm11) does not meet the defrost conditions for the air conditioner 1000 to enter the defrost mode. In this case, there is no frost or less frost on the outdoor heat exchanger 202.

[0102] In step 152, it is determined that the second frequency Fn is less than or equal to the first preset frequency F1 (Fn≤F1), and the air conditioner 1000 is controlled to operate in the false defrost mode for the first preset time H1. After the operating time of the air conditioner 1000 in the false defrost mode exceeds the first preset time H1, the air conditioner 1000 is controlled to exit the false defrost mode.

[0103] After step 151, if the controller 40 further determines that the second frequency Fn is less than or equal to the first preset frequency F1, the air conditioner 1000 has temporarily returned to a stable state after a period of time following the fluctuation, and the stabilized operating frequency F (second frequency Fn) of the compressor 201 remains within the low-frequency range. Therefore, after the controller 40 determines that the first frequency Fr is less than or equal to the first preset frequency F1, the initial temperature difference ΔTm11 is less than the first preset temperature difference ΔTb1, and the second frequency Fn is less than or equal to the first preset frequency F1, the controller 40 first controls the air conditioner 1000 to operate in the false defrost mode for a first preset duration H1 to prevent defrosting during unstable operation. Then, after the air conditioner 1000 has operated in the false defrost mode for a period exceeding the first preset duration H1, the controller 40 controls the air conditioner 1000 to exit the false defrost mode to perform a defrost determination.

[0104] It should be noted that the first preset frequency F1 can be determined based on the maximum operating frequency Fmax of the compressor 201. For example, the first preset frequency F1 is equal to 30% of the maximum operating frequency Fmax of the compressor 201 (F1 = 30% Fmax). The first preset frequency F1 is the frequency threshold for the compressor 201 to operate at a low frequency. When the operating frequency F of the compressor 201 is within the first frequency range M1, for example, when the first frequency Fr is less than the first preset frequency F1 (Fr ≤ F1) or the second frequency Fn is less than the first preset frequency F1 (Fn ≤ F1), the compressor 201 operates at a low frequency.

[0105] In step 153, it is determined that the second frequency Fn is greater than the first preset frequency F1 and less than or equal to the second preset frequency F2 (F1<Fn≤F2), and the air conditioner 1000 is controlled to operate in the false defrost mode for the second preset time H2. After the operating time of the air conditioner 1000 in the false defrost mode exceeds the second preset time H2, the air conditioner 1000 is controlled to exit the false defrost mode.

[0106] After step 151, if the controller 40 further determines that the second frequency Fn is greater than the first preset frequency F1 and less than or equal to the second preset frequency F2, the air conditioner 1000 has temporarily recovered to a stable state after a certain period of time after the fluctuation, and the operating frequency F (second frequency Fn) of the compressor 201 after stabilization is within the medium frequency range. In this case, the time required for the air conditioner 1000 to recover to a stable state is longer than the time required for the air conditioner 1000 to recover to a stable state when the compressor 201 is operating at a low frequency.

[0107] Therefore, after the controller 40 determines that the first frequency Fr is less than or equal to the first preset frequency F1, the initial temperature difference ΔTm11 is less than the first preset temperature difference ΔTb1, and the second frequency Fn is greater than the first preset frequency F1 and less than or equal to the second preset frequency F2, the controller 40 first controls the air conditioner 1000 to operate in the false defrost mode for a second preset duration H2 to prevent the air conditioner 1000 from defrosting when the operation is unstable. Then, after the air conditioner 1000 has operated in the false defrost mode for a period exceeding the second preset duration H2, the controller 40 controls the air conditioner 1000 to exit the false defrost mode to perform a defrost determination. Here, the second preset duration H2 is greater than the first preset duration H1.

[0108] It should be noted that the second preset frequency F2 can be determined based on the maximum operating frequency Fmax of the compressor 201. For example, the second preset frequency F2 is equal to half of the maximum operating frequency Fmax of the compressor 201 (F2 = 1 / 2*Fmax). The second preset frequency F2 is the frequency threshold for the compressor 201 to operate at the intermediate frequency. When the operating frequency F of the compressor 201 is within the second frequency range M2, for example, when the first frequency F1 is greater than the first preset frequency F1 and less than or equal to the second preset frequency F2, or when the second frequency F2 is greater than the first preset frequency F1 and less than or equal to the second preset frequency F2, the compressor 201 operates at the intermediate frequency.

[0109] In step 154, it is determined that the second frequency Fn is greater than the second preset frequency F2 and less than or equal to the third preset frequency F3 (F2<Fn≤F3), and the air conditioner 1000 is controlled to operate in the false defrost mode for the third preset time H3, and after the air conditioner 1000 operates in the false defrost mode for more than the third preset time H3, the air conditioner 1000 is controlled to exit the false defrost mode.

[0110] After step 151, if the controller 40 further determines that the second frequency Fn is greater than the second preset frequency F2 and less than or equal to the third preset frequency F3 (F2 < Fn ≤ F3), the air conditioner 1000 has temporarily recovered to a stable state after a certain period of time after the fluctuation, and the operating frequency F (second frequency Fn) of the compressor 201 after stabilization is within the medium-high frequency range. In this case, the time required for the air conditioner 1000 to recover to a stable state is longer than the time required for the air conditioner 1000 to recover to a stable state when the compressor 201 is operating at a medium frequency.

[0111] Therefore, after the controller 40 determines that the first frequency Fr is less than or equal to the first preset frequency F1, the initial temperature difference ΔTm11 is less than the first preset temperature difference ΔTb1, and the second frequency Fn is greater than the second preset frequency F2 and less than or equal to the third preset frequency F3, the controller 40 first controls the air conditioner 1000 to operate in the false defrost mode for a third preset duration H3 to prevent the air conditioner 1000 from defrosting when its operation is unstable. Then, after the air conditioner 1000 has operated in the false defrost mode for a duration exceeding the third preset duration H3, the controller 40 controls the air conditioner 1000 to exit the false defrost mode to perform a defrost determination. Here, the third preset duration H3 is greater than the second preset duration H2.

[0112] It should be noted that the third preset frequency F3 can be determined based on the maximum operating frequency Fmax of the compressor 201. For example, the third preset frequency F3 is equal to 70% of the maximum operating frequency Fmax of the compressor 201 (F3 = 70% Fmax). The third preset frequency F3 is the frequency threshold for the compressor 201 to operate at a medium-high frequency. When the operating frequency of the compressor 201 is within the third frequency range M3, for example, when the first frequency Fr is greater than the second preset frequency F2 and less than or equal to the third preset frequency F3, or when the second frequency Fn is greater than the second preset frequency F2 and less than or equal to the third preset frequency F3, the compressor 201 operates at a medium-high frequency.

[0113] In step 155, it is determined that the second frequency Fn is greater than the third preset frequency F3 (Fn>F3), and the air conditioner 1000 is controlled to operate in the false defrost mode for the fourth preset time H4. After the operating time of the air conditioner 1000 in the false defrost mode exceeds the fourth preset time H4, the air conditioner 1000 is controlled to exit the false defrost mode.

[0114] After step 151, if the controller 40 further determines that the second frequency Fn is greater than the third preset frequency F3, the air conditioner 1000 has temporarily returned to a stable state after a certain period of time following the fluctuation, and the operating frequency F (second frequency Fn) of the compressor 201 after stabilization is within the high frequency range. In this case, the time required for the air conditioner 1000 to return to a stable state is longer than the time required for the air conditioner 1000 to return to a stable state when the compressor 201 is operating at a medium or high frequency.

[0115] Therefore, after the controller 40 determines that the first frequency Fr is less than or equal to the first preset frequency F1, the initial temperature difference ΔTm11 is less than the first preset temperature difference ΔTb1, and the second frequency is greater than the third preset frequency F3, the controller 40 first controls the air conditioner 1000 to operate in the false defrost mode for a fourth preset duration H4 to prevent the air conditioner 1000 from performing defrost when the operation is unstable. Then, after the air conditioner 1000 has operated in the false defrost mode for a period exceeding the fourth preset duration H4, the controller 40 controls the air conditioner 1000 to exit the false defrost mode to perform a defrost determination. Here, the fourth preset duration H4 is greater than the third preset duration H3.

[0116] It should be noted that when the operating frequency of the compressor 201 is within the fourth frequency range M4, for example, when the second frequency Fn is greater than the third preset frequency F3, the compressor 201 operates at a high frequency.

[0117] The higher the preset frequency range M within which the second frequency Fn after the change in the operating frequency F of the compressor 201 lies, the longer it takes for the air conditioner 1000 to return to a stable state. Therefore, the first preset time H1 is less than the second preset time H2, the second preset time H2 is less than the third preset time H3, and the third preset time H3 is less than the fourth preset time H4 (i.e., H1 < H2 < H3 < H4).

[0118] 7 is yet another flow chart of steps performed by a controller in an air conditioner according to some embodiments.

[0119] When the first frequency Fr and the initial temperature difference ΔTm11 fail to satisfy the conditions in step 151 , as shown in FIG. 7 , step 15 executed by the controller 40 further includes steps 156 to 159 .

[0120] In step 156 , it is determined that the first frequency Fr is greater than the first preset frequency F1 and less than or equal to the second preset frequency F2 ( F1 < Fr ≤ F2 ), and the initial temperature difference ΔTm11 is less than the second preset temperature difference ΔTb2 ( ΔTm11 < ΔTb2 ).

[0121] If the controller 40 determines that the first frequency Fr is greater than the first preset frequency F1 and less than or equal to the second preset frequency F2, then when the air conditioner 1000 enters the false defrost mode, the operating frequency F (first frequency Fr) of the compressor 201 is in the medium frequency range, and frost on the outdoor heat exchanger 202 is very slow or difficult to form.

[0122] In this case, if the controller 40 determines that the initial temperature difference △Tm11 is less than the second preset temperature difference △Tb1, then when the air conditioner 1000 enters the false defrost mode, the first temperature difference △Tm1 (initial temperature difference △Tm11) does not meet the defrost conditions for the air conditioner 1000 to enter the defrost mode. In this case, there is no frost or less frost on the outdoor heat exchanger 202.

[0123] In step 157, it is determined that the second frequency Fn is greater than the first preset frequency F1 and less than or equal to the second preset frequency F2, and the air conditioner 1000 is controlled to operate in the false defrost mode for the fifth preset time H5. After the operating time of the air conditioner 1000 in the false defrost mode exceeds the fifth preset time H5, the air conditioner 1000 is controlled to exit the false defrost mode.

[0124] After step 156, if the controller 40 further determines that the second frequency Fn is greater than the first preset frequency F1 and less than or equal to the second preset frequency F2, the air conditioner 1000 has briefly recovered to a stable state after a certain period of time after the fluctuation, and the operating frequency F (second frequency Fn) of the stabilized compressor 201 is in the medium frequency range.

[0125] Therefore, after the controller 40 determines that the first frequency Fr is greater than the first preset frequency F1 and less than or equal to the second preset frequency F2, the initial temperature difference ΔTm11 is less than the second preset temperature difference ΔTb2, and the second frequency Fn is greater than the first preset frequency F1 and less than or equal to the second preset frequency F2, the controller 40 first controls the air conditioner 1000 to operate in the false defrost mode for a fifth preset time period H5 to prevent the air conditioner 1000 from performing defrost when the operation is unstable. Then, after the air conditioner 1000 has operated in the false defrost mode for a period exceeding the fifth preset time period H5, the controller 40 controls the air conditioner 1000 to exit the false defrost mode to perform a defrost determination.

[0126] In step 158, it is determined that the second frequency Fn is greater than the second preset frequency F2 and less than or equal to the third preset frequency F3, and the air conditioner 1000 is controlled to operate in the false defrost mode for the sixth preset time H6, and after the air conditioner 1000 operates in the false defrost mode for more than the sixth preset time H6, the air conditioner 1000 is controlled to exit the false defrost mode.

[0127] After step 156, if the controller 40 further determines that the second frequency Fn is greater than the second preset frequency F2 and less than or equal to the third preset frequency F3, the air conditioner 1000 has temporarily recovered to a stable state after a certain period of time after the fluctuation, and the operating frequency F (second frequency Fn) of the compressor 201 after stabilization is within the medium-high frequency range. In this case, the time required for the air conditioner 1000 to recover to a stable state is longer than the time required for the air conditioner 1000 to recover to a stable state when the compressor 201 is operating at a medium frequency.

[0128] Therefore, after the controller 40 determines that the first frequency Fr is greater than the first preset frequency F1 and less than or equal to the second preset frequency F2, the initial temperature difference ΔTm11 is less than the second preset temperature difference ΔTb2, and the second frequency Fn is greater than the second preset frequency F2 and less than or equal to the third preset frequency F3, the controller 40 first controls the air conditioner 1000 to operate in the false defrost mode for a sixth preset duration H6 to prevent defrosting during unstable operation. Then, after the air conditioner 1000 has operated in the false defrost mode for a period exceeding the sixth preset duration H6, the controller 40 controls the air conditioner 1000 to exit the false defrost mode to perform a defrost determination. Here, the sixth preset duration H6 is greater than the fifth preset duration H5.

[0129] In step 159, it is determined that the second frequency Fn is greater than the third preset frequency F3, and the air conditioner 1000 is controlled to operate in the false defrost mode for the seventh preset time H7. After the operating time of the air conditioner 1000 in the false defrost mode exceeds the seventh preset time H7, the air conditioner 1000 is controlled to exit the false defrost mode.

[0130] After step 156, if the controller 40 further determines that the second frequency Fn is greater than the third predetermined frequency F3, the air conditioner 1000 has temporarily returned to a stable state after a certain period of time following the fluctuation, and the operating frequency F (second frequency Fn) of the compressor 201 after stabilization is within the high frequency range. In this case, the time required for the air conditioner 1000 to return to a stable state is longer than the time required for the air conditioner 1000 to return to a stable state when the compressor 201 is operating at a medium or high frequency.

[0131] Therefore, after the controller 40 determines that the first frequency Fr is greater than the first preset frequency F1 and less than or equal to the second preset frequency F2, the initial temperature difference ΔTm11 is less than the second preset temperature difference ΔTb2, and the second frequency Fn is greater than the third preset frequency F3, the controller 40 first controls the air conditioner 1000 to operate in the false defrost mode for the seventh preset time H7 to prevent the air conditioner 1000 from performing defrost when the operation is unstable. Then, after the air conditioner 1000 has operated in the false defrost mode for a period exceeding the seventh preset time H7, the controller 40 controls the air conditioner 1000 to exit the false defrost mode to perform a defrost determination. Here, the seventh preset time H7 is greater than the sixth preset time H6.

[0132] It should be noted that, when the outdoor ambient temperature (first temperature T1) remains unchanged, the greater the operating frequency F of the compressor 201, the lower the third temperature T3, the greater the first temperature difference ΔTm1, and the greater the required preset temperature difference B. Therefore, the second preset temperature difference ΔTb2 is greater than the first preset temperature difference ΔTb1 (i.e., ΔTb1 < ΔTb2). Furthermore, if the preset frequency range M within which the second frequency Fn falls after the change in the operating frequency F of the compressor 201 is higher, the longer it takes for the air conditioner 1000 to return to a stable state. Therefore, the fifth preset time duration H5 is less than the sixth preset time duration H6, and the sixth preset time duration H6 is less than the seventh preset time duration H7 (i.e., H5 < H6 < H7).

[0133] 8 is yet another flow chart of steps performed by a controller in an air conditioner according to some embodiments.

[0134] When the first frequency Fr and the initial temperature difference ΔTm11 fail to satisfy the conditions in step 151 or step 156 , as shown in FIG. 8 , step 15 executed by the controller 40 further includes steps 160 to 162 .

[0135] In step 160 , it is determined that the first frequency Fr is greater than the second preset frequency F2 and less than or equal to the third preset frequency F3 ( F2 < Fr ≤ F3 ), and the initial temperature difference ΔTm11 is less than the third preset temperature difference ΔTb3 ( ΔTm11 < ΔTb3 ).

[0136] If the controller 40 determines that the first frequency Fr is greater than the second preset frequency F2 and less than or equal to the third preset frequency F3, then when the air conditioner 1000 enters the pseudo-defrost mode, the operating frequency F (first frequency Fr) of the compressor 201 is in the medium and high frequency range, and frost may form on the outdoor heat exchanger 202.

[0137] In this case, if the controller 40 determines that the initial temperature difference △Tm11 is less than the third preset temperature difference △Tb3, then when the air conditioner 1000 enters the false defrost mode, the first temperature difference △Tm1 (initial temperature difference △Tm11) does not meet the defrost conditions for the air conditioner 1000 to enter the defrost mode. In this case, there is no frost or less frost on the outdoor heat exchanger 202.

[0138] In step 161, it is determined that the second frequency Fn is greater than the second preset frequency F2 and less than or equal to the third preset frequency F3, and the air conditioner 1000 is controlled to operate in the false defrost mode for the eighth preset time H8, and after the air conditioner 1000 operates in the false defrost mode for more than the eighth preset time H8, the air conditioner 1000 is controlled to exit the false defrost mode.

[0139] After step 160, if the controller 40 further determines that the second frequency Fn is greater than the second preset frequency F2 and less than or equal to the third preset frequency F3, the air conditioner 1000 has briefly recovered to a stable state after a certain period of time after the fluctuation, and the operating frequency F (second frequency Fn) of the stabilized compressor 201 is in the medium and high frequency range.

[0140] Therefore, after the controller 40 determines that the first frequency Fr is greater than the second preset frequency F2 and less than or equal to the third preset frequency F3, the initial temperature difference ΔTm11 is less than the third preset temperature difference ΔTb3, and the second frequency Fn is greater than the second preset frequency F2 and less than or equal to the third preset frequency F3, the controller 40 first controls the air conditioner 1000 to operate in the false defrost mode for an eighth preset time period H8 to prevent the air conditioner 1000 from performing defrost when the operation is unstable. Then, after the air conditioner 1000 has operated in the false defrost mode for a period exceeding the eighth preset time period H8, the controller 40 controls the air conditioner 1000 to exit the false defrost mode to perform a defrost determination.

[0141] In step 162, it is determined that the second frequency Fn is greater than the third preset frequency F3, and the air conditioner 1000 is controlled to operate in the false defrost mode for the ninth preset time H9. After the operating time of the air conditioner 1000 in the false defrost mode exceeds the ninth preset time H9, the air conditioner 1000 is controlled to exit the false defrost mode.

[0142] After step 160, if the controller 40 further determines that the second frequency Fn is greater than the third preset frequency F3, the air conditioner 1000 has temporarily returned to a stable state after a certain period of time following the fluctuation, and the operating frequency F (second frequency Fn) of the compressor 201 after stabilization is within the high frequency range. In this case, the time required for the air conditioner 1000 to return to a stable operating state is longer than the time required for the air conditioner 1000 to return to a stable operating state when the compressor 201 is operating at a medium or high frequency.

[0143] Therefore, after the controller 40 determines that the first frequency Fr is greater than the second preset frequency F2 and less than or equal to the third preset frequency F3, the initial temperature difference ΔTm11 is less than the third preset temperature difference ΔTb3, and the second frequency Fn is greater than the third preset frequency F3, the controller 40 first controls the air conditioner 1000 to operate in the false defrost mode for a ninth preset time period H9 to prevent the air conditioner 1000 from defrosting during unstable operation. Then, after the air conditioner 1000 has operated in the false defrost mode for a period exceeding the ninth preset time period H9, the controller 40 controls the air conditioner 1000 to exit the false defrost mode to perform a defrost determination. Here, the ninth preset time period H9 is greater than the eighth preset time period H8.

[0144] It should be noted that, when the outdoor ambient temperature (first temperature T1) remains unchanged, the higher the operating frequency F of the compressor 201, the lower the third temperature T3, the larger the first temperature difference ΔTm1, and the larger the required preset temperature difference B. Therefore, the third preset temperature difference ΔTb3 is greater than the second preset temperature difference ΔTb2 (i.e., ΔTb2 < ΔTb3). Furthermore, if the preset frequency range M within which the second frequency Fn falls after the change in the operating frequency F of the compressor 201 is higher, the air conditioner 1000 takes longer to return to a stable state. Therefore, the eighth preset time duration H8 is less than the ninth preset time duration H9 (i.e., H8 < H9).

[0145] 9 is yet another flow chart of steps performed by a controller in an air conditioner according to some embodiments.

[0146] In some embodiments, as shown in FIG. 9 , step 11 performed by the controller 40 includes step 110 .

[0147] In step 110 , it is determined that the operating time of the air conditioner 1000 in the heating mode reaches the target duration, and it is determined that the air conditioner 1000 is in the heating mode.

[0148] In some embodiments, the target duration is greater than or equal to 10 minutes, for example, the target duration is 10 minutes, 11 minutes, or 12 minutes.

[0149] Typically, 10 minutes after compressor 201 begins operating, its operating frequency F stabilizes, resulting in smooth overall operation of air conditioner 1000. If compressor 201 operates for less than 10 minutes after it begins operating, the operating frequency F of compressor 201 fluctuates significantly, and the acquired data may fluctuate significantly, potentially affecting the accuracy of the determination. Therefore, it is necessary to wait for a period of time after compressor 201 begins operating before determining whether the defrost mode is in effect.

[0150] Figure 10 is another flow chart of steps performed by a controller in an air conditioner according to some embodiments. Figure 11 is another flow chart of steps performed by a controller in an air conditioner according to some embodiments.

[0151] The steps performed by the controller 40 are exemplarily described below with reference to FIG. 10 and FIG. 11 .

[0152] As shown in FIG. 10 , the controller 40 is configured to execute steps 21 to 24 .

[0153] In step 21 , when the air conditioner 1000 is in the heating mode, the operating frequency F of the compressor 201 is obtained.

[0154] In step 22 , it is determined whether the increase value ΔF of the operating frequency F of the compressor 201 within the preset period G is greater than or equal to the preset frequency threshold A; if so, step 23 is executed; if not, step 24 is executed.

[0155] In step 23, the air conditioner 1000 is controlled to enter the pseudo-defrost mode.

[0156] In step 24 , the air conditioner 1000 is controlled to maintain heating operation, and the process returns to step 21 .

[0157] As shown in FIG. 11 , after entering the false defrost mode, the controller 40 is further configured to execute steps 25 to 29 .

[0158] In step 25 , the operating frequency F of the compressor 201 when the air conditioner 1000 enters the false defrost mode is determined to be the first frequency Fr, the first temperature difference ΔTm1 is determined to be the initial temperature difference ΔTm11 , and the air conditioner 1000 is controlled to heat rather than defrost.

[0159] In step 26 , a first preset frequency F1 , a second preset frequency F2 , and a third preset frequency F3 are determined according to the maximum operating frequency Fmax of the compressor 201 , so as to obtain four preset frequency ranges M.

[0160] In step 27 , when it is determined that the operating frequency F of the compressor 201 remains unchanged for at least two consecutive preset periods G, the operating frequency F of the compressor 201 at the current moment is determined to be the second frequency Fn.

[0161] In step 28, based on the relationship between the first frequency Fr and the second frequency Fn and the preset frequency range M, and the relationship between the initial temperature difference △Tm11 and the preset temperature difference B, the preset time H required for the air conditioner 1000 to operate in the false defrost mode is determined, and the air conditioner 1000 is controlled to operate in the false defrost mode for the preset time H.

[0162] In step 29 , after determining that the operating time of the air conditioner 1000 in the false defrost mode exceeds the preset time H, the air conditioner 1000 is controlled to exit the false defrost mode.

[0163] The above description mainly uses the example of the controller 40 controlling the air conditioner 1000 to enter the false defrost mode according to the operating frequency F of the compressor 201. Of course, in some embodiments, the controller 40 can also control the air conditioner 1000 to enter the false defrost mode according to other parameters.

[0164] 12 is yet another flow chart of steps performed by a controller in an air conditioner according to some embodiments.

[0165] For example, as shown in FIG. 12 , steps 11 and 12 performed by the controller 40 may be replaced by steps 11 ′ and 12 ′.

[0166] In step 11 ′, when the air conditioner 1000 is in the heating mode, the set temperature and the second temperature T2 are acquired to determine the second temperature difference ΔTm2 (indoor temperature difference).

[0167] The second temperature difference ΔTm2 is the difference between the set temperature and the second temperature T2. The set temperature is a temperature pre-set based on the user's indoor ambient temperature requirements. The user can set the set temperature through the remote control 30 or the air conditioning application (Application, APP) on the mobile terminal or the control panel.

[0168] In step 12 ′, it is determined that the increase in the second temperature difference ΔTm2 within the preset period G is greater than or equal to the preset temperature difference threshold D, and the air conditioner 1000 is controlled to enter the false defrost mode.

[0169] The preset temperature difference threshold D is a pre-set threshold. The preset period G is similar to the preset period G in the above description, and will not be repeated here. It should be noted that the preset period G here serves as the detection period of the second temperature difference ΔTm2.

[0170] For example, if the second temperature T2 cannot meet the user's needs, the set temperature needs to be increased to increase the second temperature T2. However, if the set temperature increases but the second temperature T2 does not, the second temperature difference ΔTm2 increases. In this case, the controller 40 controls the operating frequency of the compressor 201 to increase to improve the heating capacity of the air conditioner 1000.

[0171] For another example, after the air conditioner 1000 operates in heating mode for a period of time, the second temperature T2 gradually rises, and the second temperature difference ΔTm2 decreases. The smaller the second temperature difference ΔTm2, the closer the second temperature T2 is to the set temperature. In other words, the indoor ambient temperature approaches the temperature set by the user. In this case, the operating frequency of the air conditioner's compressor 201 is reduced from high frequency to low frequency. When the second temperature T2 is equal to the set temperature, the air conditioner's compressor 201 remains operating at a medium or low frequency.

[0172] While compressor 201 is operating at a medium or low frequency, frequent door openings or people entering and exiting the room may cause second temperature T2 to drop, increasing second temperature difference ΔTm2 and causing compressor 201 to increase its frequency again. If compressor 201's operating frequency F suddenly increases, third temperature T3 rapidly decreases and remains below third temperature T3 when compressor 201 is operating at a high frequency. In this case, there may be little or no frost on outdoor unit 20. If controller 40 determines whether air conditioner 1000 should defrost based on first temperature difference ΔTm1, air conditioner 1000 may mistakenly enter defrost mode, causing second temperature T2 to drop, impacting heating performance.

[0173] For another example, when the air conditioner 1000 switches from silent or sleep mode to low-frequency or low-wind heating mode, and after the air conditioner 1000 operates in this mode (low-frequency or low-wind heating mode) for a period of time, the second temperature T2 is still lower than the set temperature, then the controller 40 controls the air conditioner 1000 to enter high-wind heating mode. Alternatively, after the air conditioner 1000 operates in high-wind or strong-wind mode for a period of time, the second temperature T2 is the same as the set temperature, and the air conditioner 1000 switches to low-wind mode, the heat exchange capacity of the indoor heat exchanger 101 decreases, and the second temperature T2 increases. In this case, current protection or indoor coil overload protection may be triggered to cause the compressor 201 to reduce the operating frequency F, so that the air conditioner 1000 operates in low-wind mode and the compressor 201 maintains low-frequency operation. Thus, after the air conditioner 1000 has been running for a period of time, if the air conditioner 1000 is adjusted to enter high or strong wind mode, the operating frequency F of the compressor 201 will increase rapidly, and the third temperature T3 will decrease rapidly, so that the first temperature difference ΔTm1 meets the defrost condition. In this case, the controller 40 controls the air conditioner 1000 to enter the defrost mode, causing the second temperature T2 to decrease, affecting the heating effect of the air conditioner 1000.

[0174] Therefore, when the air conditioner 1000 operates normally, the difference between the set temperature and the second temperature T2 (indoor temperature difference) may fluctuate slightly due to various reasons. To solve this problem, a preset temperature difference threshold D and a preset period G are set in some embodiments of the present disclosure.

[0175] The increase in the second temperature difference ΔTm2 refers to the increase in the second temperature difference ΔTm2 within a preset period G. For example, the second temperature difference ΔTm2 last acquired by the controller 40 is recorded as the first indoor temperature difference ΔTm2(p-1), and the second temperature difference ΔTm2 currently acquired by the controller 40 is recorded as the second indoor temperature difference ΔTm2(p), where p ≥ 1. In this case, the increase in the second temperature difference ΔTm2 is the difference between the second indoor temperature difference ΔTm2(p) and the first indoor temperature difference ΔTm2(p-1). If the increase in the second temperature difference ΔTm2 within the preset period G is greater than a preset temperature difference threshold D, the controller 40 determines that the second temperature difference ΔTm2 has increased rapidly in a short period of time, and the operating frequency F of the compressor 201 has also increased in a short period of time. Thus, to prevent the air conditioner 1000 from erroneously performing defrost, the controller 40 can control the air conditioner 1000 to enter a false defrost mode and then determine whether to control the air conditioner 1000 to enter a defrost mode. In this way, the air conditioner 1000 can be prevented from being defrosted when there is no frost or from being defrosted frequently, thereby improving the operating stability of the air conditioner 1000 and reducing energy consumption.

[0176] In some embodiments, the preset temperature difference threshold D is greater than or equal to 1°C. For example, the preset temperature difference threshold D is 1°C, 2°C, 3°C, or 4°C. While the air conditioner 1000 is operating, the second temperature difference ΔTm2 may vary slightly due to various reasons. If the preset temperature difference threshold D is set to a small value, the air conditioner 1000 may frequently enter the false defrost mode, affecting the normal operation of the air conditioner 1000. Therefore, the preset temperature difference threshold D can be set to be greater than a certain value. Different preset temperature difference thresholds D can be preset according to the configuration of the air conditioner 1000.

[0177] The above description mainly uses the example of the controller 40 controlling the air conditioner 1000 to enter the false defrost mode according to the second temperature difference ΔTm2. Of course, in some embodiments, the controller 40 can also control the air conditioner 1000 to enter the false defrost mode according to other parameters.

[0178] 13 is yet another flow chart of steps performed by a controller in an air conditioner according to some embodiments.

[0179] For example, as shown in FIG13 , steps 11 and 12 executed by the controller 40 may be replaced by steps 11 ″ and 12 ″.

[0180] In step 11″, when the air conditioner 1000 is in heating mode, the speed S of the indoor fan 102 is obtained.

[0181] In step 12 ″, it is determined that the increase value ΔS of the speed S of the indoor fan 102 within the preset period G is greater than or equal to the preset speed value C, and the air conditioner 1000 is controlled to enter the false defrost mode.

[0182] When the operating frequency F of the compressor 201 suddenly increases, the operating status of the corresponding components in the air conditioner 1000 changes. The parameters that characterize the fluctuations in the operating status of the air conditioner 1000 include the fourth temperature T4, the third temperature T3, the fifth temperature T5, the operating frequency F of the compressor 201 and the rotational speed S of the indoor fan 102, etc. Table 1 describes the degree of influence of the rotational speed S of the indoor fan 102 and the operating frequency F of the compressor 201 on the fourth temperature T4, the third temperature T3 and the fifth temperature T5, respectively. The number of "★" in Table 1 represents the degree of correlation. In other words, the more "★", the greater the degree of influence. It should be noted that the fifth temperature T5 (exhaust temperature) is the temperature of the gaseous refrigerant discharged by the compressor 201.

[0183] Table 1 Relationship between the speed of the indoor fan and the operating frequency of the compressor and the third temperature, the fourth temperature and the fifth temperature

[0184] When the rotational speed S of the indoor fan 102 changes suddenly, the air conditioner 1000 may experience fluctuations. For example, when the heating demand increases, the heating demand can be met by increasing the rotational speed S of the indoor fan 102. When the air conditioner 1000 increases the air volume, or switches from sleep or silent mode to heating mode, the rotational speed S of the indoor fan 102 is increased. As can be seen from Table 1, a sudden change in the rotational speed S of the indoor fan 102 has a significant impact on the fourth temperature T4. Therefore, the controller 40 can control the air conditioner 1000 based on the rotational speed S of the indoor fan 102 to avoid defrosting the air conditioner 1000 when there is no frost or frequent defrosting, thereby improving the operating stability of the air conditioner 1000 and reducing energy consumption.

[0185] Therefore, in some embodiments of the present disclosure, a preset rotation speed value C and a preset period G are set.

[0186] The preset speed value C is a preset threshold. The preset period G is similar to the preset period G described above and will not be repeated here. It should be noted that the preset period G here is used as the detection period of the speed S of the indoor fan 102.

[0187] The increase in the speed S of the indoor fan 102, ΔS, refers to the increase in the speed S of the indoor fan 102 within a preset period G. During normal operation of the air conditioner 1000, the speed S of the indoor fan 102 may fluctuate slightly due to various reasons. For example, the speed S of the indoor fan 102 last acquired by the controller 40 is recorded as the first speed S(q-1), and the speed S of the indoor fan 102 currently acquired by the controller 40 is recorded as the second speed S(q), where q ≥ 1. In this case, the increase in the speed S of the indoor fan 102, ΔS, is the difference between the second speed S(q) and the first speed S(q-1) (i.e., ΔS = S(q) - S(q-1)). If the increase in the speed S of the indoor fan 102, ΔS, is determined to be greater than or equal to the preset speed value C within the preset period G, the controller 40 determines that the speed S of the indoor fan 102 increased rapidly within a short period of time, causing fluctuations in the air conditioner 1000. Thus, to prevent the air conditioner 1000 from mistakenly defrosting, the controller 40 can control the air conditioner 1000 to enter the false defrost mode and then determine whether to control the air conditioner 1000 to enter the defrost mode. In this way, it is possible to avoid the air conditioner 1000 defrosting when there is no frost and frequently defrosting, thereby improving the operating stability of the air conditioner 1000 and reducing energy consumption.

[0188] In some embodiments, the preset speed value C is greater than or equal to 50 r / min. For example, the preset speed value C is 50 r / min, 60 r / min, or 70 r / min. If the preset speed value C is set to a smaller value, the air conditioner 1000 may frequently enter the false defrost mode, affecting the normal operation of the air conditioner 1000. Therefore, the preset speed value C can be set to be greater than a certain value. It should be noted that the preset speed value C is a speed value preset based on experiments.

[0189] An increase in the second temperature difference ΔTm2 or the increase in the speed S of the indoor fan 102 by ΔS causes the operating frequency F of the compressor 201 to rapidly increase, resulting in fluctuations in the air conditioner 1000. This rapidly decreases the third temperature T3, and the first temperature difference ΔTm1 satisfies the defrost condition, causing the controller 40 to control the air conditioner 1000 to enter defrost mode. Furthermore, after the fluctuations in the air conditioner 1000 caused by the change in the operating frequency F of the compressor 201, the air conditioner 1000 stabilizes after a certain period of time. Therefore, during the sudden increase in the operating frequency F of the compressor 201 and the subsequent period, the first temperature difference ΔTm1 cannot indicate the frosting condition of the outdoor unit 20. Consequently, the controller 40 cannot accurately determine whether the first temperature difference ΔTm1 satisfies the defrost condition.

[0190] Therefore, to avoid situations where the air conditioner 1000 defrosts when there is no frost or frequently defrosts, some embodiments of the present disclosure provide an air conditioner 1000. By determining the increase in the second temperature difference ΔTm2 within a preset period G, or the increase in the speed S of the indoor fan 102 by ΔS, the controller 40 can control the air conditioner 1000 to enter a false defrost mode and then determine whether to control the air conditioner 1000 to enter a defrost mode. This can avoid situations where the air conditioner 1000 defrosts when there is no frost or frequently defrosts, thereby improving the operational stability of the air conditioner 1000 and reducing energy consumption.

[0191] It should be noted that the motor of the indoor fan 102 can be a PG motor, which is a motor with a Hall element and has a speed feedback circuit to feedback the speed S of the indoor fan 102. The controller 40 can obtain the speed S of the indoor fan 102 through the speed feedback circuit. Of course, the controller 40 can obtain the speed S of the indoor fan 102 through other methods, and this disclosure does not limit this.

[0192] In some embodiments, as shown in FIG. 9 , step 11 ′ or 11 ″ performed by the controller 40 includes step 110 ′.

[0193] In step 110', it is determined that the operating time of the air conditioner 1000 in the heating mode reaches the target duration, and the air conditioner 1000 is determined to be in the heating mode. Here, the target duration can be greater than or equal to 20 minutes. For example, the target duration is 20 minutes, 21 minutes, or 22 minutes.

[0194] 14 is yet another flow chart of steps performed by a controller in an air conditioner according to some embodiments.

[0195] The following is an exemplary description of the above steps executed by the controller 40 with reference to FIG. 14 .

[0196] In some embodiments, as shown in FIG. 14 , steps 21 and 22 performed by the controller 40 may be replaced by steps 21 ′ and 22 ′.

[0197] In step 21 ′, it is determined that the air conditioner 1000 is in the heating mode, and the set temperature and the second temperature T2 are obtained, or the speed S of the indoor fan 102 is obtained.

[0198] In step 22 ′, it is determined whether the increase in the second temperature difference ΔTm2 is greater than or equal to the preset temperature difference threshold D, or whether the increase in the speed S of the indoor fan 102 ΔS is greater than or equal to the preset speed value C within the preset period G. If so, step 23 is executed; if not, step 24 is executed.

[0199] To prevent the air conditioner 1000 from defrosting when there is no frost or from performing frequent defrosting, some embodiments of the present disclosure provide an air conditioner 1000. By determining the increase in the operating frequency F of the compressor 201 by ΔF or the increase in the speed S of the indoor fan 102 by ΔS, the air conditioner 1000 can be prevented from erroneously defrosting, thereby preventing the air conditioner 1000 from defrosting when there is no frost or from performing frequent defrosting, thereby improving the operating stability of the air conditioner 1000 and reducing energy consumption.

[0200] Some embodiments of the present disclosure also provide a defrost control method for an air conditioner, which is applied to a controller. The air conditioner has a similar structure to the air conditioner 1000 described above. For example, the air conditioner includes the indoor unit 10 and the outdoor unit 20 described above. The outdoor unit 20 includes a compressor 201.

[0201] In this case, as shown in FIG. 4 , the method includes steps 31 to 35 .

[0202] In step 31 , when the air conditioner 1000 is in the heating mode, the operating frequency F of the compressor 201 is obtained.

[0203] In step 32 , it is determined that within the preset period G, the increase value ΔF of the operating frequency F of the compressor 201 is greater than the preset frequency threshold A, and the air conditioner 1000 is controlled to enter the pseudo-defrost mode.

[0204] In step 33 , the operating frequency F of the compressor 201 when the air conditioner 1000 enters the false defrost mode is determined to be the first frequency Fr, the first temperature difference ΔTm1 is determined to be the initial temperature difference ΔTm11 , and the air conditioner 1000 is controlled to continue heating instead of defrosting.

[0205] In step 34 , when it is determined that the operating frequency F of the compressor 201 remains unchanged for at least two consecutive preset periods G, the operating frequency F of the compressor 201 at the current moment is determined to be the second frequency Fn.

[0206] In step 35, the air conditioner 1000 is controlled to operate in the false defrost mode for a preset time H according to the first frequency Fr, the initial temperature difference ΔTm11 and the second frequency Fn, and after the time for the air conditioner 1000 to operate in the false defrost mode exceeds the preset time H, the air conditioner 1000 is controlled to exit the false defrost mode.

[0207] In some embodiments, as shown in FIG6 , step 35 includes steps 351 to 355 .

[0208] In step 351 , it is determined that the first frequency Fr is less than or equal to the first preset frequency F1 (Fr≤F1) and the initial temperature difference ΔTm11 is less than the first preset temperature difference ΔTb1 (ΔTm11<ΔTb1).

[0209] In step 352, it is determined that the second frequency Fn is less than or equal to the first preset frequency F1 (Fn≤F1), and the air conditioner 1000 is controlled to operate in the false defrost mode for the first preset time H1. After the operating time of the air conditioner 1000 in the false defrost mode exceeds the first preset time H1, the air conditioner 1000 is controlled to exit the false defrost mode.

[0210] In step 353, it is determined that the second frequency Fn is greater than the first preset frequency F1 and less than or equal to the second preset frequency F2 (F1<Fn≤F2), and the air conditioner 1000 is controlled to operate in the false defrost mode for the second preset time H2. After the operating time of the air conditioner 1000 in the false defrost mode exceeds the second preset time H2, the air conditioner 1000 is controlled to exit the false defrost mode.

[0211] In step 354, it is determined that the second frequency Fn is greater than the second preset frequency F2 and less than or equal to the third preset frequency F3 (F2<Fn≤F3), and the air conditioner 1000 is controlled to operate in the false defrost mode for the third preset time H3, and after the air conditioner 1000 operates in the false defrost mode for more than the third preset time H3, the air conditioner 1000 is controlled to exit the false defrost mode.

[0212] In step 355, it is determined that the second frequency Fn is greater than the third preset frequency F3 (Fn>F3), and the air conditioner 1000 is controlled to operate in the false defrost mode for the fourth preset time H4. After the operating time of the air conditioner 1000 in the false defrost mode exceeds the fourth preset time H4, the air conditioner 1000 is controlled to exit the false defrost mode.

[0213] Here, the first preset frequency F1 is less than the second preset frequency F2, the second preset frequency F2 is less than the third preset frequency F3, the first preset duration H1 is less than the second preset duration H2, the second preset duration H2 is less than the third preset duration H3, and the third preset duration H3 is less than the fourth preset duration H4.

[0214] In the case that the first frequency Fr and the initial temperature difference ΔTm11 cannot satisfy the conditions in step 351 , as shown in FIG. 7 , step 35 further includes steps 356 to 359 .

[0215] In step 356 , it is determined that the first frequency Fr is greater than the first preset frequency F1 and less than or equal to the second preset frequency F2 ( F1 < Fr ≤ F2 ), and the initial temperature difference ΔTm11 is less than the second preset temperature difference ΔTb2 ( ΔTm11 < ΔTb2 ).

[0216] In step 357, it is determined that the second frequency Fn is greater than the first preset frequency F1 and less than or equal to the second preset frequency F2, and the air conditioner 1000 is controlled to operate in the false defrost mode for the fifth preset time H5. After the operating time of the air conditioner 1000 in the false defrost mode exceeds the fifth preset time H5, the air conditioner 1000 is controlled to exit the false defrost mode.

[0217] In step 358, it is determined that the second frequency Fn is greater than the second preset frequency F2 and less than or equal to the third preset frequency F3, and the air conditioner 1000 is controlled to operate in the false defrost mode for the sixth preset time H6. After the operating time of the air conditioner 1000 in the false defrost mode exceeds the sixth preset time H6, the air conditioner 1000 is controlled to exit the false defrost mode.

[0218] In step 359, it is determined that the second frequency Fn is greater than the third preset frequency F3, and the air conditioner 1000 is controlled to operate in the false defrost mode for the seventh preset time H7. After the operating time of the air conditioner 1000 in the false defrost mode exceeds the seventh preset time H7, the air conditioner 1000 is controlled to exit the false defrost mode.

[0219] Here, the second preset temperature difference ΔTb2 is greater than the first preset temperature difference ΔTb1. The fifth preset time length H5 is less than the sixth preset time length H6, and the sixth preset time length H6 is less than the seventh preset time length H7.

[0220] In the case that the first frequency Fr and the initial temperature difference ΔTm11 cannot satisfy the conditions in step 351 and step 356 , as shown in FIG. 8 , step 35 further includes steps 360 to 362 .

[0221] In step 360 , it is determined that the first frequency Fr is greater than the second preset frequency F2 and less than or equal to the third preset frequency F3 ( F2 < Fr ≤ F3 ), and the initial temperature difference ΔTm11 is less than the third preset temperature difference ΔTb3 ( ΔTm11 < ΔTb3 ).

[0222] In step 361, it is determined that the second frequency Fn is greater than the second preset frequency F2 and less than or equal to the third preset frequency F3, and the air conditioner 1000 is controlled to operate in the false defrost mode for the eighth preset time H8, and after the air conditioner 1000 operates in the false defrost mode for more than the eighth preset time H8, the air conditioner 1000 is controlled to exit the false defrost mode.

[0223] In step 362, it is determined that the second frequency Fn is greater than the third preset frequency F3, and the air conditioner 1000 is controlled to operate in the false defrost mode for the ninth preset time H9. After the operating time of the air conditioner 1000 in the false defrost mode exceeds the ninth preset time H9, the air conditioner 1000 is controlled to exit the false defrost mode.

[0224] Here, the third preset temperature difference ΔTb3 is greater than the second preset temperature difference ΔTb2. The eighth preset time length H8 is less than the ninth preset time length H9.

[0225] In some embodiments, as shown in FIG. 9 , step 31 includes step 310 .

[0226] In step 310 , it is determined that the operating time of the air conditioner 1000 in the heating mode reaches the target duration, and it is determined that the air conditioner 1000 is in the heating mode.

[0227] The above air conditioner defrost control method is mainly described by controlling the air conditioner 1000 to enter the false defrost mode according to the operating frequency F of the compressor 201. Of course, in some embodiments, the air conditioner 1000 can also be controlled to enter the false defrost mode according to other parameters.

[0228] For example, as shown in FIG. 12 , step 31 and step 32 may be replaced by step 31 ′ and step 32 ′.

[0229] In step 31 ′, when the air conditioner 1000 is in the heating mode, the set temperature and the second temperature T2 are acquired to determine the second temperature difference ΔTm2 (indoor temperature difference).

[0230] In step 32 ′, it is determined that the increase in the second temperature difference ΔTm2 within the preset period G is greater than or equal to the preset temperature difference threshold D, and the air conditioner 1000 is controlled to enter the false defrost mode.

[0231] The above description mainly uses the example of the controller 40 controlling the air conditioner 1000 to enter the false defrost mode according to the second temperature difference ΔTm2. Of course, in some embodiments, the controller 40 can also control the air conditioner 1000 to enter the false defrost mode according to other parameters.

[0232] For example, as shown in FIG13 , steps 31 and 32 executed by the controller 40 may be replaced by steps 31 ″ and 32 ″.

[0233] In step 31 ″, when the air conditioner 1000 is in the heating mode, the rotation speed S of the indoor fan 102 is obtained.

[0234] In step 32 ″, it is determined that the increase value ΔS of the speed S of the indoor fan 102 within the preset period G is greater than or equal to the preset speed value C, and the air conditioner 1000 is controlled to enter the false defrost mode.

[0235] It should be noted that the defrost control method for the air conditioner provided in some embodiments of the present disclosure is the same as all the process steps executed by the controller 40 in the air conditioner provided in the above embodiments, and the working principles and beneficial effects of the two correspond one to one, so they will not be repeated here.

[0236] In the defrost control method for an air conditioner provided in some embodiments of the present disclosure, the air conditioner 1000 can be controlled to enter a false defrost mode based on the operating frequency F of the compressor 201, or the difference between the set temperature and the indoor temperature, or the speed S of the indoor fan 102. Furthermore, the air conditioner 1000 can be controlled to operate in the false defrost mode for a preset time H based on the first frequency Fr, the initial temperature difference ΔTm11, and the second frequency Fn to avoid defrosting the air conditioner 1000 when there is no frost or frequent defrosting. After the air conditioner 1000 operates in the false defrost mode for a time period exceeding the preset time H, the air conditioner 1000 is controlled to exit the false defrost mode, thereby improving the operating stability of the air conditioner 1000 and reducing energy consumption.

[0237] In the description of the above embodiments, specific features, structures, materials or characteristics may be combined in an appropriate manner in any one or more embodiments or examples.

[0238] Those skilled in the art will understand that the scope of the present invention is not limited to the above specific embodiments, and that certain elements of the embodiments may be modified and replaced without departing from the spirit of the present application. The scope of the present application is limited by the appended claims.

Claims

1. An air conditioner, comprising: Indoor unit; an outdoor unit comprising a compressor, an outdoor heat exchanger, and a first temperature sensor, wherein the first temperature sensor is disposed on the outdoor heat exchanger and is configured to detect an outdoor ambient temperature; as well as A controller configured to: When the air conditioner is in a heating mode, obtaining operating parameters of the air conditioner; controlling the air conditioner to enter a false defrost mode according to the operating parameters; determining that the operating frequency of the compressor when the air conditioner enters the false defrost mode is a first frequency, and that the outdoor temperature difference when the air conditioner enters the false defrost mode is an initial temperature difference, and controlling the air conditioner to continue heating rather than defrosting; the outdoor temperature difference is the difference between the outdoor ambient temperature and the temperature of the coil in the outdoor heat exchanger; If it is determined that the operating frequency of the compressor remains unchanged for at least two consecutive preset periods, determining the operating frequency of the compressor at the current moment to be the second frequency; According to the first frequency, the initial temperature difference and the second frequency, the air conditioner is controlled to operate in the false defrost mode for a preset time, and after the time for the air conditioner to operate in the false defrost mode exceeds the preset time, the air conditioner is controlled to exit the false defrost mode.

2. The air conditioner according to claim 1, wherein The operating parameters include the operating frequency of the compressor, and the controller is configured to: When the air conditioner is in the heating mode, obtaining the operating frequency of the compressor; If it is determined that the increase in the operating frequency of the compressor within a preset period is greater than a preset frequency threshold, the air conditioner is controlled to enter the false defrost mode.

3. The air conditioner according to claim 2, wherein: After determining the second frequency, the controller is configured to: If it is determined that the first frequency is less than or equal to a first preset frequency, the initial temperature difference is less than the first preset temperature difference, and the second frequency is less than or equal to the first preset frequency, controlling the air conditioner to operate in a false defrost mode for a first preset time period, and controlling the air conditioner to exit the false defrost mode after the time period for which the air conditioner operates in the false defrost mode exceeds the first preset time period; If it is determined that the first frequency is less than or equal to the first preset frequency, the initial temperature difference is less than the first preset temperature difference, and the second frequency is greater than the first preset frequency and less than or equal to a second preset frequency, the air conditioner is controlled to operate in the false defrost mode for a second preset time, and after the air conditioner operates in the false defrost mode for a time period exceeding the second preset time period, the air conditioner is controlled to exit the false defrost mode; If it is determined that the first frequency is less than or equal to the first preset frequency, the initial temperature difference is less than the first preset temperature difference, and the second frequency is greater than the second preset frequency and less than or equal to a third preset frequency, the air conditioner is controlled to operate in the false defrost mode for a third preset time period, and after the air conditioner operates in the false defrost mode for a time period exceeding the third preset time period, the air conditioner is controlled to exit the false defrost mode; If it is determined that the first frequency is less than or equal to the first preset frequency, the initial temperature difference is less than the first preset temperature difference, and the second frequency is greater than the third preset frequency, the air conditioner is controlled to operate in the false defrost mode for a fourth preset time period, and after the air conditioner operates in the false defrost mode for a time period exceeding the fourth preset time period, the air conditioner is controlled to exit the false defrost mode; in The first preset frequency is less than the second preset frequency, the second preset frequency is less than the third preset frequency, the first preset duration is less than the second preset duration, the second preset duration is less than the third preset duration, and the third preset duration is less than the fourth preset duration. The preset durations include the first preset duration, the second preset duration, the third preset duration, and the fourth preset duration.

4. The air conditioner according to claim 3, wherein: After determining the second frequency, the controller is further configured to: If it is determined that the first frequency is greater than the first preset frequency and less than or equal to the second preset frequency, the initial temperature difference is less than the second preset temperature difference, and the second frequency is greater than the first preset frequency and less than or equal to the second preset frequency, the air conditioner is controlled to operate in the false defrost mode for a fifth preset time, and after the time the air conditioner operates in the false defrost mode exceeds the fifth preset time, the air conditioner is controlled to exit the false defrost mode. Defrost mode; If it is determined that the first frequency is greater than the first preset frequency and less than or equal to the second preset frequency, the initial temperature difference is less than the second preset temperature difference, and the second frequency is greater than the second preset frequency and less than or equal to the third preset frequency, the air conditioner is controlled to operate in the false defrost mode for a sixth preset time period, and after the air conditioner operates in the false defrost mode for a time period exceeding the sixth preset time period, the air conditioner is controlled to exit the false defrost mode; If it is determined that the first frequency is greater than the first preset frequency and less than or equal to the second preset frequency, the initial temperature difference is less than the second preset temperature difference, and the second frequency is greater than the third preset frequency, the air conditioner is controlled to operate in the false defrost mode for a seventh preset time period, and after the air conditioner operates in the false defrost mode for a time period exceeding the seventh preset time period, the air conditioner is controlled to exit the false defrost mode; in The second preset temperature difference is greater than the first preset temperature difference, the fifth preset time length is less than the sixth preset time length, the sixth preset time length is less than the seventh preset time length, and the preset time lengths include the fifth preset time length, the sixth preset time length, and the seventh preset time length.

5. The air conditioner according to claim 4, wherein After determining the second frequency, the controller is further configured to: If it is determined that the first frequency is greater than the second preset frequency and less than or equal to the third preset frequency, the initial temperature difference is less than the third preset temperature difference, and the second frequency is greater than the second preset frequency and less than or equal to the third preset frequency, the air conditioner is controlled to operate in the false defrost mode for an eighth preset time period, and after the air conditioner operates in the false defrost mode for a time period exceeding the eighth preset time period, the air conditioner is controlled to exit the false defrost mode; If it is determined that the first frequency is greater than the second preset frequency and less than or equal to the third preset frequency, the initial temperature difference is less than the third preset temperature difference, and the second frequency is greater than the third preset frequency, the air conditioner is controlled to operate in the false defrost mode for a ninth preset time period, and after the air conditioner operates in the false defrost mode for a time period exceeding the ninth preset time period, the air conditioner is controlled to exit the false defrost mode; in The third preset temperature difference is greater than the second preset temperature difference, the eighth preset time length is less than the ninth preset time length, and the preset time lengths include the eighth preset time length and the ninth preset time length.

6. The air conditioner according to claim 1, wherein The indoor unit includes an indoor heat exchanger and a second temperature sensor, the second temperature sensor being disposed on the indoor heat exchanger and configured to detect an indoor ambient temperature. The operating parameters include a set temperature and an indoor temperature difference, the indoor temperature difference being the difference between the set temperature and the indoor ambient temperature. The set temperature is a desired indoor ambient temperature. The controller is configured to: When the air conditioner is in the heating mode, obtaining the set temperature and the indoor temperature difference; If it is determined that the increase in the indoor temperature difference within the preset period is greater than a preset temperature difference threshold, the air conditioner is controlled to enter the false defrost mode.

7. The air conditioner according to claim 6, wherein After determining the second frequency, the controller is configured to: If it is determined that the first frequency is less than or equal to a first preset frequency, the initial temperature difference is less than the first preset temperature difference, and the second frequency is less than or equal to the first preset frequency, controlling the air conditioner to operate in a false defrost mode for a first preset time period, and controlling the air conditioner to exit the false defrost mode after the time period for which the air conditioner operates in the false defrost mode exceeds the first preset time period; If it is determined that the first frequency is less than or equal to the first preset frequency, the initial temperature difference is less than the first preset temperature difference, and the second frequency is greater than the first preset frequency and less than or equal to a second preset frequency, the air conditioner is controlled to operate in the false defrost mode for a second preset time, and after the air conditioner operates in the false defrost mode for a time period exceeding the second preset time period, the air conditioner is controlled to exit the false defrost mode; If it is determined that the first frequency is less than or equal to the first preset frequency, the initial temperature difference is less than the first preset temperature difference, and the second frequency is greater than the second preset frequency and less than or equal to a third preset frequency, the air conditioner is controlled to operate in the false defrost mode for a third preset time period, and after the air conditioner operates in the false defrost mode for a time period exceeding the third preset time period, the air conditioner is controlled to exit the false defrost mode; If it is determined that the first frequency is less than or equal to the first preset frequency, the initial temperature difference is less than the first preset frequency. temperature difference, and the second frequency is greater than the third preset frequency, controlling the air conditioner to operate in the false defrost mode for a fourth preset time period, and controlling the air conditioner to exit the false defrost mode after the time period for which the air conditioner operates in the false defrost mode exceeds the fourth preset time period; in The first preset frequency is less than the second preset frequency, the second preset frequency is less than the third preset frequency, the first preset duration is less than the second preset duration, the second preset duration is less than the third preset duration, and the third preset duration is less than the fourth preset duration. The preset durations include the first preset duration, the second preset duration, the third preset duration, and the fourth preset duration.

8. The air conditioner according to claim 7, wherein: After determining the second frequency, the controller is further configured to: If it is determined that the first frequency is greater than the first preset frequency and less than or equal to the second preset frequency, the initial temperature difference is less than the second preset temperature difference, and the second frequency is greater than the first preset frequency and less than or equal to the second preset frequency, the air conditioner is controlled to operate in the false defrost mode for a fifth preset time period, and after the air conditioner operates in the false defrost mode for a time period exceeding the fifth preset time period, the air conditioner is controlled to exit the false defrost mode; If it is determined that the first frequency is greater than the first preset frequency and less than or equal to the second preset frequency, the initial temperature difference is less than the second preset temperature difference, and the second frequency is greater than the second preset frequency and less than or equal to the third preset frequency, the air conditioner is controlled to operate in the false defrost mode for a sixth preset time period, and after the air conditioner operates in the false defrost mode for a time period exceeding the sixth preset time period, the air conditioner is controlled to exit the false defrost mode; If it is determined that the first frequency is greater than the first preset frequency and less than or equal to the second preset frequency, the initial temperature difference is less than the second preset temperature difference, and the second frequency is greater than the third preset frequency, the air conditioner is controlled to operate in the false defrost mode for a seventh preset time period, and after the air conditioner operates in the false defrost mode for a time period exceeding the seventh preset time period, the air conditioner is controlled to exit the false defrost mode; in The second preset temperature difference is greater than the first preset temperature difference, the fifth preset time length is less than the sixth preset time length, the sixth preset time length is less than the seventh preset time length, and the preset time lengths include the fifth preset time length, the sixth preset time length, and the seventh preset time length.

9. The air conditioner according to claim 8, wherein After determining the second frequency, the controller is further configured to: If it is determined that the first frequency is greater than the second preset frequency and less than or equal to the third preset frequency, the initial temperature difference is less than the third preset temperature difference, and the second frequency is greater than the second preset frequency and less than or equal to the third preset frequency, the air conditioner is controlled to operate in the false defrost mode for an eighth preset time period, and after the air conditioner operates in the false defrost mode for a time period exceeding the eighth preset time period, the air conditioner is controlled to exit the false defrost mode; If it is determined that the first frequency is greater than the second preset frequency and less than or equal to the third preset frequency, the initial temperature difference is less than the third preset temperature difference, and the second frequency is greater than the third preset frequency, the air conditioner is controlled to operate in the false defrost mode for a ninth preset time period, and after the air conditioner operates in the false defrost mode for a time period exceeding the ninth preset time period, the air conditioner is controlled to exit the false defrost mode; in The third preset temperature difference is greater than the second preset temperature difference, the eighth preset time length is less than the ninth preset time length, and the preset time lengths include the eighth preset time length and the ninth preset time length.

10. The air conditioner according to claim 1, wherein The indoor unit includes an indoor fan; the operating parameter includes a rotation speed of the indoor fan, and the controller is configured to: When the air conditioner is in the heating mode, obtaining the rotation speed of the indoor fan; If it is determined that the increase in the rotation speed of the indoor fan within the preset period is greater than the preset rotation speed value, the air conditioner is controlled to enter the false defrost mode.

11. The air conditioner according to claim 1, wherein The controller satisfies at least one of the following: After controlling the air conditioner to enter the false defrost mode, the controller is configured to: control the outdoor ambient temperature to not satisfy the condition for the air conditioner to perform defrost, so as to control the air conditioner not to perform defrost; or, After controlling the air conditioner to exit the false defrost mode, the controller is further configured to cancel the limitation on the outdoor ambient temperature to cancel the restriction that the air conditioner does not perform defrost in the false defrost mode.

12. A defrost control method for an air conditioner, applied to a controller of the air conditioner, wherein the air conditioner includes an indoor unit and an outdoor unit, the outdoor unit includes a compressor, an outdoor heat exchanger, and a first temperature sensor, the first temperature sensor being disposed on the outdoor heat exchanger and configured to detect an outdoor ambient temperature, the method comprising: When the air conditioner is in a heating mode, obtaining operating parameters of the air conditioner; controlling the air conditioner to enter a false defrost mode according to the operating parameters; determining that the operating frequency of the compressor when the air conditioner enters the false defrost mode is a first frequency, and that the outdoor temperature difference when the air conditioner enters the false defrost mode is an initial temperature difference, and controlling the air conditioner to continue heating rather than defrosting; the outdoor temperature difference is the difference between the outdoor ambient temperature and the temperature of the coil in the outdoor heat exchanger; If it is determined that the operating frequency of the compressor remains unchanged for at least two consecutive preset periods, determining the operating frequency of the compressor at the current moment to be the second frequency; According to the first frequency, the initial temperature difference and the second frequency, the air conditioner is controlled to operate in the false defrost mode for a preset time, and after the time for the air conditioner to operate in the false defrost mode exceeds the preset time, the air conditioner is controlled to exit the false defrost mode.

13. The defrost control method for an air conditioner according to claim 12, wherein: The operating parameter includes the operating frequency of the compressor, and the method includes: When the air conditioner is in the heating mode, obtaining the operating frequency of the compressor; If it is determined that the increase in the operating frequency of the compressor within a preset period is greater than a preset frequency threshold, the air conditioner is controlled to enter the false defrost mode.

14. The defrost control method for an air conditioner according to claim 13, wherein: The step of controlling the air conditioner to operate in the false defrost mode for a preset time period based on the first frequency, the initial temperature difference, and the second frequency, and controlling the air conditioner to exit the false defrost mode after the time period for which the air conditioner operates in the false defrost mode exceeds the preset time period, comprises: If it is determined that the first frequency is less than or equal to a first preset frequency, the initial temperature difference is less than the first preset temperature difference, and the second frequency is less than or equal to the first preset frequency, controlling the air conditioner to operate in a false defrost mode for a first preset time period, and controlling the air conditioner to exit the false defrost mode after the time period for which the air conditioner operates in the false defrost mode exceeds the first preset time period; If it is determined that the first frequency is less than or equal to the first preset frequency, the initial temperature difference is less than the first preset temperature difference, and the second frequency is greater than the first preset frequency and less than or equal to a second preset frequency, the air conditioner is controlled to operate in the false defrost mode for a second preset time, and after the air conditioner operates in the false defrost mode for a time period exceeding the second preset time period, the air conditioner is controlled to exit the false defrost mode; If it is determined that the first frequency is less than or equal to the first preset frequency, the initial temperature difference is less than the first preset temperature difference, and the second frequency is greater than the second preset frequency and less than or equal to a third preset frequency, the air conditioner is controlled to operate in the false defrost mode for a third preset time period, and after the air conditioner operates in the false defrost mode for a time period exceeding the third preset time period, the air conditioner is controlled to exit the false defrost mode; If it is determined that the first frequency is less than or equal to the first preset frequency, the initial temperature difference is less than the first preset temperature difference, and the second frequency is greater than the third preset frequency, the air conditioner is controlled to operate in the false defrost mode for a fourth preset time period, and after the time for the air conditioner to operate in the false defrost mode exceeds the fourth preset time period, the air conditioner is controlled to exit the false defrost mode; wherein The first preset frequency is less than the second preset frequency, the second preset frequency is less than the third preset frequency, the first preset duration is less than the second preset duration, the second preset duration is less than the third preset duration, and the third preset duration is less than the fourth preset duration. The preset durations include the first preset duration, the second preset duration, the third preset duration, and the fourth preset duration.

15. The defrost control method for an air conditioner according to claim 14, wherein: The method further includes controlling the air conditioner to operate in the false defrost mode for a preset time period based on the first frequency, the initial temperature difference, and the second frequency, and controlling the air conditioner to exit the false defrost mode after the time period for which the air conditioner operates in the false defrost mode exceeds the preset time period. If it is determined that the first frequency is greater than the first preset frequency and less than or equal to the second preset frequency, the initial temperature difference is less than the second preset temperature difference, and the second frequency is greater than the first preset frequency and less than or equal to the second preset frequency, the air conditioner is controlled to operate in the false defrost mode for a fifth preset time period, and after the air conditioner operates in the false defrost mode for a time period exceeding the fifth preset time period, the air conditioner is controlled to exit the false defrost mode; If it is determined that the first frequency is greater than the first preset frequency and less than or equal to the second preset frequency, the initial temperature difference is less than the second preset temperature difference, and the second frequency is greater than the second preset frequency and less than or equal to the third preset frequency, the air conditioner is controlled to operate in the false defrost mode for a sixth preset time period, and after the air conditioner operates in the false defrost mode for a time period exceeding the sixth preset time period, the air conditioner is controlled to exit the false defrost mode; If it is determined that the first frequency is greater than the first preset frequency and less than or equal to the second preset frequency, the initial temperature difference is less than the second preset temperature difference, and the second frequency is greater than the third preset frequency, the air conditioner is controlled to operate in the false defrost mode for a seventh preset time period, and after the time for the air conditioner to operate in the false defrost mode exceeds the seventh preset time period, the air conditioner is controlled to exit the false defrost mode; wherein The second preset temperature difference is greater than the first preset temperature difference, the fifth preset time length is less than the sixth preset time length, the sixth preset time length is less than the seventh preset time length, and the preset time lengths include the fifth preset time length, the sixth preset time length, and the seventh preset time length.

16. The defrost control method for an air conditioner according to claim 15, wherein: The method further includes controlling the air conditioner to operate in the false defrost mode for a preset time period based on the first frequency, the initial temperature difference, and the second frequency, and controlling the air conditioner to exit the false defrost mode after the time period for which the air conditioner operates in the false defrost mode exceeds the preset time period. If it is determined that the first frequency is greater than the second preset frequency and less than or equal to the third preset frequency, the initial temperature difference is less than the third preset temperature difference, and the second frequency is greater than the second preset frequency and less than or equal to the third preset frequency, the air conditioner is controlled to operate in the false defrost mode for an eighth preset time period, and after the air conditioner operates in the false defrost mode for a time period exceeding the eighth preset time period, the air conditioner is controlled to exit the false defrost mode; If it is determined that the first frequency is greater than the second preset frequency and less than or equal to the third preset frequency, the initial temperature difference is less than the third preset temperature difference, and the second frequency is greater than the third preset frequency, the air conditioner is controlled to operate in the false defrost mode for a ninth preset time period, and after the time for the air conditioner to operate in the false defrost mode exceeds the ninth preset time period, the air conditioner is controlled to exit the false defrost mode; wherein The third preset temperature difference is greater than the second preset temperature difference, the eighth preset time length is less than the ninth preset time length, and the preset time lengths include the eighth preset time length and the ninth preset time length.

17. The defrost control method for an air conditioner according to claim 12, wherein: The indoor unit includes an indoor heat exchanger and a second temperature sensor, the second temperature sensor being disposed on the indoor heat exchanger and configured to detect an indoor ambient temperature, the operating parameters including a set temperature and an indoor temperature difference, the indoor temperature difference being the difference between the set temperature and the indoor ambient temperature, the set temperature being a desired indoor ambient temperature, and the method comprising: When the air conditioner is in the heating mode, obtaining the set temperature and the indoor temperature difference; If it is determined that the increase in the indoor temperature difference within the preset period is greater than a preset temperature difference threshold, the air conditioner is controlled to enter the false defrost mode.

18. The defrost control method for an air conditioner according to claim 17, wherein: The step of controlling the air conditioner to operate in the false defrost mode for a preset time period based on the first frequency, the initial temperature difference, and the second frequency, and controlling the air conditioner to exit the false defrost mode after the time period for which the air conditioner operates in the false defrost mode exceeds the preset time period, comprises: If it is determined that the first frequency is less than or equal to a first preset frequency, the initial temperature difference is less than the first preset temperature difference, and the second frequency is less than or equal to the first preset frequency, the air conditioner is controlled to operate in a false defrost mode for a first preset time period, and after the air conditioner operates in the false defrost mode for a time period exceeding the first preset time period, the air conditioner is controlled to exit the false defrost mode; If it is determined that the first frequency is less than or equal to the first preset frequency, the initial temperature difference is less than the first preset frequency. temperature difference, and the second frequency is greater than the first preset frequency and less than or equal to a second preset frequency, controlling the air conditioner to operate in the false defrost mode for a second preset time, and controlling the air conditioner to exit the false defrost mode after the time the air conditioner operates in the false defrost mode exceeds the second preset time; If it is determined that the first frequency is less than or equal to the first preset frequency, the initial temperature difference is less than the first preset temperature difference, and the second frequency is greater than the second preset frequency and less than or equal to a third preset frequency, the air conditioner is controlled to operate in the false defrost mode for a third preset time period, and after the air conditioner operates in the false defrost mode for a time period exceeding the third preset time period, the air conditioner is controlled to exit the false defrost mode; If it is determined that the first frequency is less than or equal to the first preset frequency, the initial temperature difference is less than the first preset temperature difference, and the second frequency is greater than the third preset frequency, the air conditioner is controlled to operate in the false defrost mode for a fourth preset time period, and after the time for the air conditioner to operate in the false defrost mode exceeds the fourth preset time period, the air conditioner is controlled to exit the false defrost mode; wherein The first preset frequency is less than the second preset frequency, the second preset frequency is less than the third preset frequency, the first preset duration is less than the second preset duration, the second preset duration is less than the third preset duration, and the third preset duration is less than the fourth preset duration. The preset durations include the first preset duration, the second preset duration, the third preset duration, and the fourth preset duration.

19. The defrost control method for an air conditioner according to claim 18, wherein: The method further includes controlling the air conditioner to operate in the false defrost mode for a preset time period based on the first frequency, the initial temperature difference, and the second frequency, and controlling the air conditioner to exit the false defrost mode after the time period for which the air conditioner operates in the false defrost mode exceeds the preset time period. If it is determined that the first frequency is greater than the first preset frequency and less than or equal to the second preset frequency, the initial temperature difference is less than the second preset temperature difference, and the second frequency is greater than the first preset frequency and less than or equal to the second preset frequency, the air conditioner is controlled to operate in the false defrost mode for a fifth preset time period, and after the air conditioner operates in the false defrost mode for a time period exceeding the fifth preset time period, the air conditioner is controlled to exit the false defrost mode; If it is determined that the first frequency is greater than the first preset frequency and less than or equal to the second preset frequency, the initial temperature difference is less than the second preset temperature difference, and the second frequency is greater than the second preset frequency and less than or equal to the third preset frequency, the air conditioner is controlled to operate in the false defrost mode for a sixth preset time period, and after the air conditioner operates in the false defrost mode for a time period exceeding the sixth preset time period, the air conditioner is controlled to exit the false defrost mode; If it is determined that the first frequency is greater than the first preset frequency and less than or equal to the second preset frequency, the initial temperature difference is less than the second preset temperature difference, and the second frequency is greater than the third preset frequency, the air conditioner is controlled to operate in the false defrost mode for a seventh preset time period, and after the time for the air conditioner to operate in the false defrost mode exceeds the seventh preset time period, the air conditioner is controlled to exit the false defrost mode; wherein The second preset temperature difference is greater than the first preset temperature difference, the fifth preset time length is less than the sixth preset time length, the sixth preset time length is less than the seventh preset time length, and the preset time lengths include the fifth preset time length, the sixth preset time length, and the seventh preset time length.

20. The defrost control method for an air conditioner according to claim 19, wherein: The method further includes controlling the air conditioner to operate in the false defrost mode for a preset time period based on the first frequency, the initial temperature difference, and the second frequency, and controlling the air conditioner to exit the false defrost mode after the time period for which the air conditioner operates in the false defrost mode exceeds the preset time period. If it is determined that the first frequency is greater than the second preset frequency and less than or equal to the third preset frequency, the initial temperature difference is less than the third preset temperature difference, and the second frequency is greater than the second preset frequency and less than or equal to the third preset frequency, the air conditioner is controlled to operate in the false defrost mode for an eighth preset time period, and after the air conditioner operates in the false defrost mode for a time period exceeding the eighth preset time period, the air conditioner is controlled to exit the false defrost mode; If it is determined that the first frequency is greater than the second preset frequency and less than or equal to the third preset frequency, the initial temperature difference is less than the third preset temperature difference, and the second frequency is greater than the third preset frequency, the air conditioner is controlled to operate in the false defrost mode for a ninth preset time, and the air conditioner is operated in the false defrost mode for a ninth preset time. After exceeding the ninth preset time, the air conditioner is controlled to exit the false defrost mode; wherein The third preset temperature difference is greater than the second preset temperature difference, the eighth preset time length is less than the ninth preset time length, and the preset time lengths include the eighth preset time length and the ninth preset time length.

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