Air conditioner and control method thereof

Abstract

The invention discloses an air conditioner and a control method thereof.The air conditioner comprises a refrigerant circulation loop, an electronic expansion valve, an indoor fan, an outdoor fan, an exhaust temperature sensor, an outdoor environment temperature sensor, an outdoor coil pipe temperature sensor and a controller; and when it is determined that the air conditioner meets the condition of entering the first defrosting mode according to the first outdoor environment temperature, the execution time of the defrosting action is determined in the first defrosting mode, and / or when it is determined that the air conditioner meets the condition of entering the second defrosting mode according to the outdoor coil pipe temperature, the defrosting action is executed in the second defrosting mode immediately. The defrosting efficiency is improved, and the comfort of a user and the reliability of the air conditioner are improved.

Description

Technical Field

[0001] The present invention relates to the technical field of air conditioners, and particularly to an air conditioner and a control method thereof. Background Art

[0002] During the actual installation and use of an air conditioner, as the usage time increases, it is easy to cause problems such as dirty blockage of its heat exchanger, affecting the normal heat exchange efficiency of the heat exchanger. At the same time, if the air conditioner is not tightly sealed during installation, refrigerant micro-leakage may occur. Therefore, problems such as dirty blockage of the heat exchanger and poor installation sealing of the air conditioner are likely to cause refrigerant flow deviation.

[0003] In the prior art, for a conventional variable-frequency air conditioner, the frosting situation is monitored through the temperature of the outer coil. When the temperature of the outer coil drops to a certain value, the unit will enter the defrosting mode. However, when the unit has a flow deviation, some heat exchanger flow paths become overheated, causing the overheated U-tubes not to frost, while other places frost thickly. If the U-tube where the outer coil temperature is located happens to be in an overheated state, the detected value of the outer coil temperature is on the high side, and the defrosting condition cannot be triggered in time, which will further exacerbate the frosting situation of the outdoor heat exchanger, thereby affecting its performance, resulting in a decrease in the exhaust temperature and the indoor air outlet temperature, poor heating effect, affecting the user experience, and even possibly causing reliability problems of the air conditioner. Summary of the Invention

[0004] The present invention aims to solve at least one of the technical problems existing in the prior art. For this purpose, the object of the present invention is to provide an air conditioner and a control method thereof.

[0005] An air conditioner proposed by the present invention includes: a refrigerant circulation circuit that enables the refrigerant to perform a refrigeration cycle in a circuit composed of a compressor, a condenser, an expansion valve, and an evaporator, where one of the condenser and the evaporator is an outdoor heat exchanger and the other is an indoor heat exchanger; an electronic expansion valve provided between the condenser and the evaporator, and the electronic expansion valve is configured to increase the flow resistance of the refrigerant passing through the electronic expansion valve when its opening degree decreases, and decrease the flow resistance of the refrigerant passing through the electronic expansion valve when its opening degree increases; an indoor fan for driving indoor air to pass through the indoor heat exchanger by rotation so that the refrigerant exchanges heat with the indoor air; an outdoor fan for driving outdoor air to pass through the outdoor heat exchanger by rotation so that the refrigerant exchanges heat with the outdoor air; an exhaust temperature sensor for detecting the exhaust temperature of the compressor; an outdoor ambient temperature sensor for detecting the outdoor ambient temperature; an outdoor coil temperature sensor for detecting the outdoor coil temperature; a controller, and the controller is configured to: when the air conditioner starts heating operation, obtain the corresponding first outdoor ambient temperature and the outdoor coil temperature at present; judge whether the air conditioner meets the condition for entering the first defrosting mode according to the first outdoor ambient temperature, and / or judge whether the air conditioner meets the condition for entering the second defrosting mode according to the outdoor coil temperature; when it is determined according to the first outdoor ambient temperature that the air conditioner meets the condition for entering the first defrosting mode, control the air conditioner to enter the first defrosting mode, and in the first defrosting mode, determine the execution timing of the defrosting action according to the exhaust temperature of the compressor, the opening degree of the electronic expansion valve, the operating frequency of the compressor, the rotation speed of the outdoor fan, the air volume gear of the indoor fan, and the outdoor ambient temperature; and / or when it is judged according to the outdoor coil temperature that the air conditioner meets the condition for entering the second defrosting mode, control the air conditioner to enter the second defrosting mode, and in the second defrosting mode, immediately execute the defrosting action.

[0006] In addition, the air conditioner according to the embodiment of the present invention may further have the following additional technical features:

[0007] Further, when judging whether the air conditioner meets the condition for entering the first defrosting mode according to the first outdoor ambient temperature, the controller is configured to: when it is judged that the first outdoor ambient temperature does not exceed the first preset temperature, determine that the air conditioner meets the condition for entering the first defrosting mode.

[0008] Further, in the first defrosting mode, when determining the execution timing of the defrosting action according to the exhaust temperature of the compressor, the opening degree of the electronic expansion valve, the operating frequency of the compressor, the rotational speed of the outdoor fan, the wind speed gear of the indoor fan, and the outdoor ambient temperature, the controller is configured to: obtain the initial parameters corresponding to when the air conditioner enters the first defrosting mode, and the initial parameters include: the first exhaust temperature currently corresponding to the compressor, the first operating frequency currently corresponding to the compressor, the first rotational speed currently corresponding to the outdoor fan, the first wind speed gear currently corresponding to the indoor fan, the first opening degree currently corresponding to the electronic expansion valve, and the second outdoor ambient temperature corresponding to the current outdoor environment; judge the change condition of the exhaust temperature of the compressor according to the first exhaust temperature. If the change condition of the exhaust temperature does not meet the first preset change condition, return to the step of obtaining the initial parameters corresponding to when the air conditioner enters the first defrosting mode. If the change condition of the exhaust temperature meets the first preset change condition, judge the change condition of the operating frequency of the compressor according to the first operating frequency; if the change condition of the operating frequency of the compressor does not meet the second preset change condition, return to the step of obtaining the initial parameters corresponding to when the air conditioner enters the first defrosting mode. If the change condition of the operating frequency of the compressor meets the second preset change condition, judge the change condition of the opening degree of the electronic expansion valve according to the first opening degree; if the change condition of the opening degree of the electronic expansion valve does not meet the third preset change condition, return to the step of obtaining the initial parameters corresponding to when the air conditioner enters the first defrosting mode. If the change condition of the opening degree of the electronic expansion valve meets the third preset change condition, judge the change condition of the rotational speed of the outdoor fan according to the first rotational speed; if the change condition of the rotational speed of the outdoor fan does not meet the fourth preset change condition, return to the step of obtaining the initial parameters corresponding to when the air conditioner enters the first defrosting mode. If the change condition of the rotational speed of the outdoor fan meets the fourth preset change condition, judge the change condition of the wind speed gear of the indoor fan according to the first wind speed gear; if the change condition of the wind speed gear of the indoor fan does not meet the fifth preset change condition, return to the step of obtaining the initial parameters corresponding to when the air conditioner enters the first defrosting mode. If the change condition of the wind speed gear of the indoor fan meets the fifth preset change condition, judge the change condition of the outdoor ambient temperature according to the second outdoor ambient temperature; if the change condition of the outdoor ambient temperature does not meet the sixth preset change condition, return to the step of obtaining the initial parameters corresponding to when the air conditioner enters the first defrosting mode. If the change condition of the outdoor ambient temperature meets the sixth preset change condition, control the air conditioner to execute the defrosting action.

[0009] Further, when determining the change in the exhaust temperature of the compressor based on the first exhaust temperature, the controller is configured to: obtain the exhaust temperature of the compressor once every first preset time interval to obtain multiple sets of exhaust temperatures; when the multiple sets of exhaust temperatures decrease in sequence and are all less than the first exhaust temperature, and the difference between the first exhaust temperature and the last one of the multiple sets of exhaust temperatures is greater than or equal to a preset value, it is determined that the change in the exhaust temperature meets the first preset change condition; otherwise, it is determined that the change in the exhaust temperature does not meet the first preset change condition.

[0010] Further, when determining the change in the operating frequency of the compressor based on the first operating frequency, the controller is configured to: obtain the current second operating frequency of the compressor; if the current second operating frequency of the compressor is greater than or equal to the first operating frequency, it is determined that the change in the operating frequency of the compressor meets the second preset change condition; otherwise, it is determined that the change in the operating frequency of the compressor does not meet the second preset change condition.

[0011] Further, when determining the change in the opening of the electronic expansion valve based on the first opening, the controller is configured to: obtain the current second opening of the electronic expansion valve; if the current second opening of the electronic expansion valve is less than or equal to the first opening, it is determined that the change in the opening of the electronic expansion valve meets the third preset change condition; otherwise, it is determined that the change in the opening of the electronic expansion valve does not meet the third preset change condition.

[0012] Further, when determining the change in the rotational speed of the outdoor fan based on the first rotational speed, the controller is configured to: obtain the current second rotational speed of the outdoor fan; if the current second rotational speed of the outdoor fan is within a preset rotational speed range, it is determined that the change in the rotational speed of the outdoor fan meets the fourth preset change condition; otherwise, it is determined that the change in the rotational speed of the outdoor fan does not meet the fourth preset change condition, where the lower limit value and the upper limit value of the preset rotational speed range are determined based on the first rotational speed, and the second rotational speed is greater than or equal to the lower limit value of the preset rotational speed range and less than or equal to the upper limit value of the preset rotational speed range.

[0013] Further, when determining the change in the wind speed gear of the indoor fan based on the first wind speed gear, the controller is configured to: obtain the current second wind speed gear of the indoor fan; if the current second wind speed gear of the indoor fan is the same as the first wind speed gear, it is determined that the change in the wind speed gear of the indoor fan meets the fifth preset change condition; otherwise, it is determined that the change in the wind speed gear of the indoor fan does not meet the fifth preset change condition.

[0014] Further, when determining the change condition of the outdoor ambient temperature according to the second outdoor ambient temperature, the controller is configured to: obtain the current third outdoor ambient temperature; if the current third outdoor ambient temperature is within a preset temperature range, determine that the change condition of the outdoor ambient temperature meets the sixth preset change condition, otherwise, determine that the change condition of the outdoor ambient temperature does not meet the sixth preset change condition, wherein the lower limit value and the upper limit value of the preset temperature range are determined according to the second outdoor ambient temperature, and the third outdoor ambient temperature is greater than or equal to the lower limit value of the preset temperature range and less than or equal to the upper limit value of the preset temperature range.

[0015] According to the air conditioner of the embodiment of the present invention, by setting the first defrosting mode and the second defrosting mode, and selecting the corresponding defrosting mode according to the current corresponding first outdoor ambient temperature and the outdoor coil temperature, when the first outdoor ambient temperature meets the condition for entering the first defrosting mode, the execution timing of the defrosting operation is determined according to the obtained initial parameters, and / or when it is determined that the air conditioner enters the second defrosting mode according to the outdoor coil temperature, the defrosting operation is immediately executed, which can avoid the situation that the air conditioner has frost that does not melt, improve the reliability of the unit, and at the same time, can ensure timely defrosting and improve the comfort of the user.

[0016] In view of the above problems, the present invention also provides a control method for an air conditioner, which is used for the air conditioner described in any of the above embodiments. The method includes the following steps: when the air conditioner starts heating operation, obtain the current corresponding first outdoor ambient temperature and the outdoor coil temperature; determine whether the air conditioner meets the condition for entering the first defrosting mode according to the first outdoor ambient temperature, and / or determine whether the air conditioner meets the condition for entering the second defrosting mode according to the outdoor coil temperature; when it is determined according to the first outdoor ambient temperature that the air conditioner meets the condition for entering the first defrosting mode, control the air conditioner to enter the first defrosting mode, so as to determine the execution timing of the defrosting operation according to the exhaust temperature of the compressor, the opening degree of the electronic expansion valve, the operating frequency of the compressor, the rotation speed of the outdoor fan, the air volume gear of the indoor fan and the outdoor ambient temperature in the first defrosting mode; and / or when it is determined according to the outdoor coil temperature that the air conditioner meets the condition for entering the second defrosting mode, control the air conditioner to enter the second defrosting mode, so as to immediately execute the defrosting operation in the second defrosting mode.

[0017] The control method of the air conditioner according to the embodiment of the present invention sets the first defrosting mode and the second defrosting mode, selects the corresponding defrosting mode according to the current corresponding first outdoor ambient temperature and the outdoor coil temperature. When the first outdoor ambient temperature meets the condition for entering the first defrosting mode, the execution timing of the defrosting action is determined according to the obtained initial parameters, and / or when it is determined that the air conditioner enters the second defrosting mode according to the outdoor coil temperature, the defrosting action is immediately executed, which can avoid the situation of frost formation and non-defrosting of the air conditioner, improve the reliability of the unit, and at the same time, can ensure timely defrosting and improve the comfort of users.

[0018] Additional aspects and advantages of the present invention will be given in part in the following description, become apparent in part from the following description, or be learned through the practice of the present invention. Brief Description of the Drawings

[0019] The above and / or additional aspects and advantages of the present invention will become apparent and be readily understood from the description of the embodiments in conjunction with the following drawings, in which:

[0020] Figure 1 is a schematic structural diagram of an air conditioner according to an embodiment of the present invention;

[0021] Figure 2 is a schematic structural diagram of a controller according to an embodiment of the present invention;

[0022] Figure 3 is a schematic structural diagram of an air conditioner according to another embodiment of the present invention;

[0023] Figure 4 is a flowchart of a control method of an air conditioner according to an embodiment of the present invention;

[0024] Figure 5 is a flowchart of entering the first defrosting mode according to an embodiment of the present invention;

[0025] Figure 6 is a flowchart of exiting the first defrosting mode according to an embodiment of the present invention;

[0026] Figure 7 is a general flowchart of a control method of an air conditioner according to an embodiment of the present invention. Detailed Embodiments

[0027] The technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.

[0028] In the description of the present invention, it should be understood that the orientation or positional relationship indicated by the terms "center", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc. is based on the orientation or positional relationship shown in the drawings. It is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be construed as a limitation to the present invention.

[0029] The terms "first" and "second" are only used for descriptive purposes and should not be construed as indicating or implying relative importance or implicitly specifying the quantity of the indicated technical features. Thus, the features defined with "first" and "second" may explicitly or implicitly include one or more of such features. In the description of the present invention, unless otherwise stated, the meaning of "a plurality of" is two or more.

[0030] In the description of the present invention, it should be noted that unless otherwise clearly specified and defined, the terms "mounted", "connected" and "coupled" should be understood in a broad sense. For example, it may be a fixed connection, a detachable connection, or an integral connection; it may be a mechanical connection or an electrical connection; it may be directly connected or indirectly connected through an intermediate medium, and it may be the communication inside two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0031] An embodiment of the present invention provides an air conditioner 10. Referring to Figure 1 , the air conditioner 10 includes a refrigeration system for exchanging heat with indoor air to meet the cooling or heating requirements.

[0032] The refrigeration system includes a compressor, a condenser, an electronic expansion valve 12 and an evaporator. In the present invention, the air conditioner 10 performs the refrigeration cycle of the air conditioner 10 by using the compressor, the condenser, the electronic expansion valve 12 and the evaporator. The refrigeration cycle includes a series of processes involving compression, condensation, expansion and evaporation, and supplies refrigerant to the air that has been conditioned and heat-exchanged.

[0033] The compressor compresses the refrigerant gas in a high-temperature and high-pressure state and discharges the compressed refrigerant gas. The discharged refrigerant gas flows into the condenser. The condenser condenses the compressed refrigerant into a liquid phase, and the heat is released to the surrounding environment through the condensation process.

[0034] The electronic expansion valve 12 expands the liquid-phase refrigerant in a high-temperature and high-pressure state condensed in the condenser into a low-pressure liquid-phase refrigerant. The evaporator evaporates the refrigerant expanded in the electronic expansion valve 12 and returns the refrigerant gas in a low-temperature and low-pressure state to the compressor.

[0035] The evaporator can achieve a refrigeration effect by exchanging heat with the material to be cooled by utilizing the latent heat of evaporation of the refrigerant. Throughout the cycle, the air conditioner 10 can adjust the temperature of the indoor space.

[0036] The outdoor unit 2 of the air conditioner 10 refers to the part of the refrigeration cycle including the compressor and the outdoor heat exchanger. The indoor unit 1 of the air conditioner 10 includes an indoor heat exchanger, and the electronic expansion valve 12 can be provided in the indoor unit 1 or the outdoor unit 2.

[0037] The indoor heat exchanger and the outdoor heat exchanger are used as condensers or evaporators. When the indoor heat exchanger is used as a condenser, the air conditioner 10 serves as a heater in the heating mode. When the indoor heat exchanger is used as an evaporator, the air conditioner 10 serves as a cooler in the cooling mode.

[0038] The air conditioner 10 in the present invention includes an indoor unit 1 and an outdoor unit 2. The indoor unit 1 and the outdoor unit 2 can be set as an integrated machine or a split machine. The indoor unit 1 can be set as a wall-mounted type, a ceiling type, a duct type, etc., and the indoor unit 1 is installed on the top or the upper part of the indoor room.

[0039] Refer to Figure 1 , taking the indoor wall-mounted unit as an example, the indoor wall-mounted unit is usually installed at positions such as the indoor wall surface. Again, for example, the indoor cabinet (not shown in the figure) is also a form of the indoor unit 1 of the indoor unit 1.

[0040] Taking the split machine as an example, the air conditioner 10 includes an indoor unit 1 and an outdoor unit 2. Among them, the outdoor unit 2 is usually set outdoors for heat exchange with the indoor environment.

[0041] In addition, as shown in the figure, the air conditioner 10 is equipped with a controller 71 to control the operation of each component in the internal air conditioner 10, so that each component of the air conditioner 10 operates to achieve each predetermined function of the air conditioner 10. Among them, a control device 200 is also attached to the air conditioner 10. Exemplarily, the control device 200 is specifically set as a remote controller, and the remote controller has a function of communicating with the controller 71 using, for example, infrared rays or other communication methods. The remote controller is used for users to perform various controls on the air conditioner 10 to realize the interaction between the user and the air conditioner 10.

[0042] In the embodiment of the present invention, the indoor unit 1 of the air conditioner 10 is set at the top or the upper part of the indoor. Generally speaking, the installation height of the indoor unit 1 is higher than the user's activity area. The indoor unit 1 includes an air return opening and an air outlet communicating with the indoor. The indoor air passes through the air return opening into the indoor unit 1 and flows back into the indoor through the air outlet.

[0043] In the refrigerant circulation circuit of the present invention, the refrigerant circulates in a circuit composed of a compressor, a condenser, an electronic expansion valve 12, and an evaporator. One of the condenser and the evaporator is an outdoor heat exchanger, and the other is an indoor heat exchanger. The indoor heat exchanger is used for heat exchange with the air in the indoor unit 1, and the outdoor unit 2 heat exchanger is used for heat exchange with the air in the outdoor unit 2, so as to meet the cooling or heating requirements of the air conditioner 10.

[0044] The indoor unit 1 further includes an indoor fan, which is arranged near the air return opening or the air outlet of the indoor heat exchanger and is used to send the heat-exchanged air into the room. The indoor fan includes multiple gears for changing the air outlet speed of the air flow at the air outlet.

[0045] At the position of the air outlet, there is a wind deflector. By changing its relative rotation angle with the air outlet, the wind deflector adjusts the outflow direction of the air flowing through the air outlet, thereby affecting the air temperature stratification in the room.

[0046] In the embodiment shown in the present invention, the air conditioner 10 further includes a controller 71, which refers to a device that can generate operation control signals according to instruction operation codes and timing signals to instruct the air conditioner 10 to execute control instructions. For example, in response to the power-on or power-off instruction issued by the user received, the controller 71 can execute operations related to the object selected by the power-on or power-off instruction.

[0047] The embodiment of the present invention also provides a schematic diagram of the hardware structure of the controller 71, as Figure 2 shown. The controller 71 includes a processor 83. Optionally, it further includes a memory 82 and a communication interface 84 connected to the processor 83. The processor 83, the memory 82, and the communication interface 84 are connected through a bus 81.

[0048] The processor 83 can be a central processing unit 83 (CPU), a general-purpose processor 83, a network processor 83 (NP), a digital signal processor 83 (DSP), a microprocessor 83, a microcontroller 718, a programmable logic device (PLD), or any combination thereof. The processor 83 can also be any other device with processing functions, such as a circuit, a device, or a software module. The processor 83 can also include multiple CPUs, and the processor 83 can be a single-core (single CPU) processor 83 or a multi-core (multi CPU) processor 83. Here, the processor 83 can refer to one or more devices, circuits, or processing cores for processing data (such as computer program instructions).

[0049] The memory 82 can be a read only memory (ROM), or other types of static storage devices that can store static information and instructions, a random access memory (RAM), or other types of dynamic storage devices that can store information and instructions. It can also be an electrically erasable programmable read only memory (EEPROM), a compact disc read only memory (CD ROM), or other optical disc storage, optical disc storage (including compact discs, laser discs, optical discs, digital versatile discs, Blu-ray discs, etc.), magnetic disk storage media, or other magnetic storage devices, or any other medium that can be used to carry or store the desired program code in the form of instructions or data structures and can be accessed by a computer. The embodiments of the present invention do not impose any restrictions on this. The memory 82 can exist independently or be integrated with the processor 83. Among them, the memory 82 can contain computer program code. The processor 83 is used to execute the computer program code stored in the memory 82, thereby implementing the control method of the air conditioner provided by the embodiments of the present invention.

[0050] The communication interface 84 can be used to communicate with other devices or communication networks (such as Ethernet, radio access network (RAN), wireless local area networks (WLAN), etc.). The communication interface 84 can be a module, a circuit, a transceiver, or any device capable of implementing communication.

[0051] The bus 81 can be a peripheral component interconnect (PCI) bus 81 or an extended industry standard architecture (EISA) bus 81, etc. The bus 81 can be divided into an address bus 81, a data bus 81, a control bus 81, etc. For the sake of convenience of representation, Figure 2 only a thick line is used to represent it in the figure, but it does not mean that there is only one bus 81 or one type of bus 81.

[0052] Next, refer to Figures 3 - 7 to describe the air conditioner and its control method according to the embodiments of the present invention.

[0053] Figure 3 is a schematic structural diagram of an air conditioner according to an embodiment of the present invention. As Figure 3As shown, an air conditioner 10 includes: a refrigerant circulation circuit 11, an electronic expansion valve 12, an indoor fan 13, an outdoor fan 14, an exhaust temperature sensor 15, an outdoor ambient temperature sensor 16, an outdoor coil temperature sensor 17, and a controller 71. Among them, the refrigerant circulation circuit 11 enables the refrigerant to perform a refrigeration cycle in a circuit composed of a compressor, a condenser, an expansion valve, and an evaporator. One of the condenser and the evaporator is an outdoor heat exchanger, and the other is an indoor heat exchanger; the electronic expansion valve 12 is provided between the condenser and the evaporator. The electronic expansion valve 12 is configured to increase the flow resistance of the refrigerant passing through the electronic expansion valve 12 when its opening degree decreases, and decrease the flow resistance of the refrigerant passing through the electronic expansion valve 12 when its opening degree increases; the indoor fan 13 is used to drive indoor air to pass through the indoor heat exchanger by rotation, so that the refrigerant exchanges heat with the indoor air; the outdoor fan 14 is used to drive outdoor air to pass through the outdoor heat exchanger by rotation, so that the refrigerant exchanges heat with the outdoor air; the exhaust temperature sensor 15 is used to detect the exhaust temperature of the compressor; the outdoor ambient temperature sensor 16 is used to detect the outdoor ambient temperature; the outdoor coil temperature sensor 17 is used to detect the outdoor coil temperature.

[0054] The controller 71 is configured to: when the air conditioner 10 starts heating operation, obtain the current corresponding first outdoor ambient temperature and outdoor coil temperature; determine whether the air conditioner 10 meets the conditions for entering the first defrosting mode according to the first outdoor ambient temperature, and / or determine whether the air conditioner 10 meets the conditions for entering the second defrosting mode according to the outdoor coil temperature; when it is determined according to the first outdoor ambient temperature that the air conditioner 10 meets the conditions for entering the first defrosting mode, control the air conditioner 10 to enter the first defrosting mode, so as to determine the execution timing of the defrosting operation according to the exhaust temperature of the compressor, the opening degree of the electronic expansion valve 12, the operating frequency of the compressor, the rotation speed of the outdoor fan 14, the wind speed gear of the indoor fan 13, and the outdoor ambient temperature in the first defrosting mode; and / or when it is determined according to the outdoor coil temperature that the air conditioner 10 meets the conditions for entering the second defrosting mode, control the air conditioner 10 to enter the second defrosting mode, so as to immediately execute the defrosting operation in the second defrosting mode.

[0055] Specifically, after the air conditioner 10 enters the defrosting mode, it will heat the surface of the condenser to melt the frost. If defrosting is carried out at an inappropriate time, it will affect the heating capacity of the air conditioner 10, cause the indoor temperature to drop, result in waste of energy, and affect the working efficiency of the air conditioner 10. Therefore, in the embodiments of the present invention, by setting the first defrosting mode and the second defrosting mode, and selecting the corresponding defrosting mode by obtaining the current corresponding first outdoor ambient temperature and outdoor coil temperature, the situation of frost not melting can be avoided, and the reliability of the unit can be improved. Based on the obtained first outdoor ambient temperature, the controller 71 will judge whether the air conditioner 10 meets the conditions for entering the first defrosting mode. For example, when the first outdoor ambient temperature does not exceed a certain temperature threshold, the first defrosting mode is triggered. At the same time or independently, the controller 71 will also judge whether the air conditioner 10 meets the conditions for entering the second defrosting mode according to the outdoor coil temperature. If the outdoor coil temperature is lower than a certain threshold, the second defrosting condition may be triggered.

[0056] In the first defrosting mode, the controller 71 will comprehensively consider multiple parameters such as the exhaust temperature of the compressor, the opening degree of the electronic expansion valve 12, the operating frequency of the compressor, the rotation speed of the outdoor fan 14, the wind speed gear of the indoor fan 13, and the outdoor ambient temperature to judge the motivation for executing the defrosting action, that is, to judge when to start defrosting, ensure that defrosting is executed at an appropriate time, and avoid the decline of the heating effect; in the second defrosting mode, the controller 71 will control the air conditioner 10 to immediately execute the defrosting action, that is, in the second defrosting mode, defrosting is directly carried out. Among them, the defrosting action is achieved by changing the reversing valve, making the evaporator on the indoor side become the condenser, and performing the exchange between the indoor and outdoor units to achieve the purpose of defrosting. Specifically, in the normal heating mode, the indoor side of the air conditioner 10 is the evaporator, which absorbs the heat in the room and discharges it to the outside; while the outdoor side is the condenser, which releases heat to the outdoor environment. However, in the defrosting mode, by operating the reversing valve, the flow direction of the refrigerant will change. The indoor side that was originally the evaporator becomes the condenser, and the outdoor side that was originally the condenser becomes the evaporator. This conversion makes the condenser on the indoor side release heat to the room, while the evaporator on the outdoor side absorbs the heat from the outside. Since the evaporator on the outdoor side is now in the heat absorption state, its surface temperature will rise, thereby melting the previously formed ice and frost. In this way, through the role exchange between the indoor and outdoor units, the purpose of defrosting is achieved.

[0057] In an embodiment of the present invention, when judging whether the air conditioner 10 meets the conditions for entering the first defrosting mode according to the first outdoor ambient temperature, the controller 71 is configured to: when it is judged that the first outdoor ambient temperature does not exceed the first preset temperature, determine that the air conditioner 10 meets the conditions for entering the first defrosting mode.

[0058] Specifically, when the controller 71 determines whether the air conditioner 10 enters the first defrosting mode, it mainly makes a judgment based on the comparison result between the first outdoor ambient temperature and the first preset temperature. When the first outdoor ambient temperature does not exceed the first preset temperature, for example, the first outdoor ambient temperature is denoted as Tw, the first preset temperature is denoted as Twa and Twa = 10 °C. When the first outdoor ambient temperature Tw ≤ the first preset temperature Twa (i.e., Tw ≤ 10 °C), it can be determined that the air conditioner 10 meets the condition for entering the first defrosting mode, thereby realizing the control of the defrosting operation of the air conditioner 10 and improving the operation efficiency and reliability of the air conditioner 10 in a low-temperature environment.

[0059] In an embodiment of the present invention, in the first defrosting mode, when determining the execution timing of the defrosting action according to the exhaust temperature of the compressor, the opening degree of the electronic expansion valve 12, the operating frequency of the compressor, the rotational speed of the outdoor fan 13, the air volume gear of the indoor fan 14, and the outdoor ambient temperature, the controller 71 is configured to: obtain the initial parameters corresponding to when the air conditioner 10 enters the first defrosting mode. The initial parameters include: the first exhaust temperature currently corresponding to the compressor, the first operating frequency currently corresponding to the compressor, the first rotational speed currently corresponding to the outdoor fan 14, the first air volume gear currently corresponding to the indoor fan 13, the first opening degree currently corresponding to the electronic expansion valve 12, and the second outdoor ambient temperature corresponding to the current outdoor environment.

[0060] In an embodiment of the present invention, the change situation of the exhaust temperature of the compressor is judged according to the first exhaust temperature. If the change situation of the exhaust temperature does not meet the first preset change condition, the step of obtaining the initial parameters corresponding to when the air conditioner 10 enters the first defrosting mode is returned. If the change situation of the exhaust temperature meets the first preset change condition, the change situation of the operating frequency of the compressor is judged according to the first operating frequency; if the change situation of the operating frequency of the compressor does not meet the second preset change condition, the step of obtaining the initial parameters corresponding to when the air conditioner 10 enters the first defrosting mode is returned. If the change situation of the operating frequency of the compressor meets the second preset change condition, the change situation of the opening degree of the electronic expansion valve 12 is judged according to the first opening degree; if the change situation of the opening degree of the electronic expansion valve 12 does not meet the third preset change condition, the step of obtaining the initial parameters corresponding to when the air conditioner 10 enters the first defrosting mode is returned. If the change situation of the opening degree of the electronic expansion valve 12 meets the third preset change condition, the change situation of the rotational speed of the outdoor fan 14 is judged according to the first rotational speed.

[0061] In an embodiment of the present invention, if the rotational speed change of the outdoor fan 14 does not meet the fourth preset change condition, return to the step of obtaining the initial parameters corresponding to when the air conditioner 10 enters the first defrosting mode. If the rotational speed change of the outdoor fan 14 meets the fourth preset change condition, judge the change of the wind speed gear of the indoor fan 13 according to the first wind speed gear. If the change of the wind speed gear of the indoor fan 13 does not meet the fifth preset change condition, return to the step of obtaining the initial parameters corresponding to when the air conditioner 10 enters the first defrosting mode. If the change of the wind speed gear of the indoor fan 13 meets the fifth preset change condition, judge the change of the outdoor ambient temperature according to the second outdoor ambient temperature. If the change of the outdoor ambient temperature does not meet the sixth preset change condition, return to the step of obtaining the initial parameters corresponding to when the air conditioner 10 enters the first defrosting mode. If the change of the outdoor ambient temperature meets the sixth preset change condition, control the air conditioner 10 to perform a defrosting action.

[0062] In the embodiment, according to the exhaust temperature of the compressor, the opening degree of the electronic expansion valve 12, the operating frequency of the compressor, the rotational speed of the outdoor fan 13, the wind speed gear of the indoor fan 14, and the outdoor ambient temperature, the initial parameters corresponding to when the air conditioner 10 enters the first defrosting mode can be obtained. The initial parameters include, for example, the first exhaust temperature corresponding to the compressor currently, the first operating frequency corresponding to the compressor currently, the first rotational speed corresponding to the outdoor fan 14 currently, the first wind speed gear corresponding to the indoor fan 13 currently, the first opening degree corresponding to the electronic expansion valve 12 currently, and the second outdoor ambient temperature corresponding to the current outdoor environment. For example, the first exhaust temperature is denoted as Tp0, the first operating frequency is denoted as F0, the first rotational speed is denoted as Nw0, the first wind speed gear is denoted as D0, the first opening degree is denoted as B0, and the second outdoor temperature is denoted as Tw0. Next, the controller 71 will judge the initial parameters one by one according to the preset order and conditions. First, judge whether the change of the exhaust temperature of the compressor meets the first preset change condition. If not, obtain the initial parameters again. If so, continue to judge whether the change of the operating frequency of the compressor meets the second preset change condition, and so on. Judge the change of the opening degree of the electronic expansion valve 12, the change of the rotational speed of the outdoor fan 14, the change of the wind speed gear of the indoor fan 13, and the change of the outdoor ambient temperature in turn. In each judgment, if the corresponding parameter change does not meet the preset change condition, the controller 71 will return to the step of obtaining the initial parameters and start a new round of judgment. Only when the change of all initial parameters meets the preset conditions, the controller 71 will control the air conditioner 10 to perform a defrosting action.

[0063] Specifically, based on the obtained first exhaust gas temperature Tp0, the change of the exhaust gas temperature of the compressor is judged. If the change of the exhaust gas temperature does not conform to the change of the first preset condition, it will return to the step of obtaining the initial parameters corresponding to when the air conditioner 10 enters the first defrosting mode, that is, the initial parameters need to be reset or calibrated, and then try to enter the first defrosting mode again to expect to obtain the change of the exhaust gas temperature that conforms to the first preset condition. If the change of the exhaust gas temperature conforms to the first preset change condition, it can be understood that the operation of the compressor in the first defrosting mode is normal. Then, based on the first operating frequency F0 of the current compressor, the change of the operating frequency of the compressor is judged. If the change of the operating frequency of the compressor does not conform to the second preset change condition, it will return to the step of obtaining the initial parameters corresponding to when the air conditioner 10 enters the first defrosting mode. If the change of the operating frequency of the compressor conforms to the second preset change condition, it can be understood that the operating frequency of the compressor is stable in the first defrosting mode. Further, based on the first opening B0, the change of the opening of the electronic expansion valve 12 is judged. The opening of the electronic expansion valve 12 can directly affect the flow of the refrigerant in the system. If the change of the opening of the electronic expansion valve 12 does not conform to the third preset change condition, it can be understood that the current change of the opening of the electronic expansion valve 12 may affect the defrosting effect of the air conditioner 10 and needs to be readjusted. Then, it will return to the step of obtaining the initial parameters corresponding to when the air conditioner 10 enters the first defrosting mode. If the change of the opening of the electronic expansion valve 12 conforms to the third preset change condition, it can be considered that the operation of the electronic expansion valve 12 is normal in the first defrosting mode.

[0064] Next, based on the first rotational speed Nw0, the change of the rotational speed of the outdoor fan 14 is further judged. If the change of the rotational speed of the outdoor fan 14 does not conform to the fourth preset change condition, it can be understood that the change of the rotational speed of the outdoor fan 14 may affect the defrosting effect of the air conditioner 10 and needs to be readjusted. It will return to the step of obtaining the initial parameters corresponding to when the air conditioner 10 enters the first defrosting mode. If the change of the rotational speed of the outdoor fan 14 conforms to the fourth preset change condition, it can be considered that the operation of the outdoor fan 14 is normal in the first defrosting mode. Next, based on the first wind speed gear D0, the change of the wind speed gear of the indoor fan 13 is further judged. The wind speed gear of the indoor fan 13 can directly affect the cooling or heating effect indoors and the comfort of the user. If the change of the wind speed gear of the indoor fan 13 does not conform to the fifth preset change condition, it will return to the step of obtaining the initial parameters corresponding to when the air conditioner 10 enters the first defrosting mode. If the change of the wind speed gear of the indoor fan 13 conforms to the fifth preset change condition, it can be understood that the operation of the indoor fan 13 is normal in the first defrosting mode.

[0065] Next, the change of the outdoor ambient temperature will be judged according to the second outdoor ambient temperature Tw0. The outdoor ambient temperature can affect the working effect of the air conditioner 10. If the change of the outdoor ambient temperature does not meet the sixth preset change condition, it can be considered that the current change of the outdoor ambient temperature may be unfavorable to the defrosting process or may lead to poor defrosting effect. Therefore, it will return to the step of obtaining the initial parameters corresponding to when the air conditioner 10 enters the first defrosting mode. If the change of the outdoor ambient temperature meets the sixth preset change condition, that is, the current outdoor ambient temperature is suitable for defrosting operation. Therefore, the controller 71 will control the air conditioner 10 to perform the defrosting action. When the defrosting is completed, the controller 71 controls the air conditioner 10 to stop performing the defrosting action and exit the first defrosting mode. Or rather, when the defrosting exit condition is met, the air conditioner 10 stops performing the defrosting action and exits the first defrosting mode. Among them, the defrosting condition is the same as that of the second defrosting mode (i.e., traditional defrosting), that is, the outdoor coil temperature meets the condition for exiting defrosting. For example, when the outdoor coil temperature is higher than the set value, the condition for exiting defrosting is met.

[0066] In an embodiment of the present invention, when judging the change of the exhaust temperature of the compressor according to the first exhaust temperature, the controller 71 is configured to: obtain the exhaust temperature of the compressor once every first preset time to obtain multiple groups of exhaust temperatures; when the multiple groups of exhaust temperatures decrease in sequence and are all less than the first exhaust temperature, and the difference between the first exhaust temperature and the last one of the multiple groups of exhaust temperatures is greater than or equal to the preset value, it is determined that the change of the exhaust temperature meets the first preset change condition; otherwise, it is determined that the change of the exhaust temperature does not meet the first preset change condition.

[0067] In the embodiment, when judging the change of the exhaust temperature of the compressor according to the first exhaust temperature Tp0, the exhaust temperature of the compressor is obtained once every first preset time to continuously monitor the change trend of the exhaust temperature, ensuring that more data is obtained for accurate analysis. By obtaining it once every first preset time, the controller 71 can obtain multiple groups of exhaust temperatures to compare the change between the first exhaust temperature Tp0 and the multiple groups of exhaust temperatures.

[0068] Specifically, for example, the first preset time is 1 minute, and the exhaust temperature of the compressor is obtained every 1 minute, obtaining three sets of exhaust temperatures of the compressor, namely the second exhaust temperature Tp1, the third exhaust temperature Tp2, and the third exhaust temperature Tp3. When the three sets of exhaust temperatures obtained are all less than the first exhaust temperature Tp0, and the difference between the first exhaust temperature Tp0 and the last one of the multiple sets of exhaust temperatures is greater than or equal to a preset value, where the preset value can be denoted as a, and a is a specific non - negative value, which can be formulated according to the actual situation. For example, a = 5, that is, Tp0>Tp1>Tp2>Tp3, and Tp0 - Tp3≥a. At this time, it can be determined that the change situation of the exhaust temperature conforms to the first preset change condition. If the multiple sets of exhaust temperatures increase in sequence and are all greater than or equal to the first exhaust temperature, and the difference between the first exhaust temperature and the last one of the multiple sets of exhaust temperatures is less than the preset value, that is, Tp0≤Tp1≤Tp2≤Tp3, and Tp0 - Tp3<a, at this time, it is determined that the change situation of the exhaust temperature does not conform to the first preset change condition.

[0069] In an embodiment of the present invention, when judging the change situation of the operating frequency of the compressor according to the first operating frequency, the controller 71 is configured to: obtain the current second operating frequency of the compressor; if the current second operating frequency of the compressor is greater than or equal to the first operating frequency, it is determined that the change situation of the operating frequency of the compressor conforms to the second preset change condition, otherwise, it is determined that the change situation of the operating frequency of the compressor does not conform to the second preset change condition.

[0070] In the embodiment, when judging the change situation of the operating frequency of the compressor according to the first operating frequency F0, it is further necessary to obtain the current second operating frequency of the compressor, denoted as F1 for example. Compare the obtained current second operating frequency F1 of the compressor with the first operating frequency F0. If the current second operating frequency F1 of the compressor is greater than or equal to the first operating frequency F0, that is, F1≥F0, it is determined that the change situation of the operating frequency of the compressor conforms to the second preset change condition. If the current second operating frequency F1 of the compressor is less than the first operating frequency F0, that is, F1<F0, it is determined that the change situation of the operating frequency of the compressor does not conform to the second preset change condition.

[0071] In an embodiment of the present invention, when judging the change situation of the opening of the electronic expansion valve 12 according to the first opening, the controller 71 is configured to: obtain the current second opening of the electronic expansion valve 12; if the current second opening of the electronic expansion valve 12 is less than or equal to the first opening, it is determined that the change situation of the opening of the electronic expansion valve 12 conforms to the third preset change condition, otherwise, it is determined that the change situation of the opening of the electronic expansion valve 12 does not conform to the third preset change condition.

[0072] Specifically, when determining the opening change of the electronic expansion valve 12 according to the first opening B0, it is further necessary to obtain the current second opening of the electronic expansion valve 12, denoted as B1 for example. Compare the obtained current second opening B1 of the electronic expansion valve 12 with the first opening B0. If the current second opening B1 of the electronic expansion valve 12 is less than or equal to the first opening B0, that is, B1≤B0, it is determined that the opening change of the electronic expansion valve 12 meets the third preset change condition. If the current second opening B1 of the electronic expansion valve 12 is greater than the first opening B0, that is, B1>B0, it is determined that the opening change of the electronic expansion valve 12 does not meet the third preset change condition.

[0073] In an embodiment of the present invention, when determining the speed change of the outdoor fan 14 according to the first speed Nw0, the controller 71 is configured to: obtain the current second speed of the outdoor fan 14; if the current second speed of the outdoor fan 14 is within a preset speed range, it is determined that the speed change of the outdoor fan 14 meets the fourth preset change condition, otherwise, it is determined that the speed change of the outdoor fan 14 does not meet the fourth preset change condition, where the lower limit and the upper limit of the preset speed range are determined according to the first speed Nw0, and the second speed is greater than or equal to the lower limit of the preset speed range and less than or equal to the upper limit of the preset speed range.

[0074] In the embodiment, when determining the speed change of the outdoor fan 14 according to the first speed Nw0, it is further necessary to obtain the current second speed of the outdoor fan 14, denoted as Nw1 for example. The lower limit and the upper limit of the preset speed range can be determined according to the first speed Nw0. The lower limit of the preset speed range is denoted as Nw0-b for example, and the upper limit of the preset speed range is denoted as Nw0+b for example, where b is a specific non-negative value and can be formulated according to the actual situation. For example, if b = 10, the lower limit of the preset speed range is Nw0-10, and the upper limit of the preset speed range is Nw0+10. Adding b as a determination condition for the preset speed range can eliminate the error of initial parameter detection.

[0075] Specifically, if the current second speed Nw1 of the outdoor fan 14 is within the preset speed range, the second speed Nw1 is greater than or equal to the lower limit Nw0-b of the preset speed range and less than or equal to the upper limit Nw0+b of the preset speed range, that is, Nw0-b≤Nw1≤Nw0+b, it is determined that the speed change of the outdoor fan 14 meets the fourth preset change condition. If the second speed Nw1 is less than the lower limit Nw0-b of the preset speed range or greater than the upper limit Nw0+b of the preset speed range, that is, Nw1<Nw0-b or Nw1>Nw0+b, it is determined that the speed change of the outdoor fan 14 does not meet the fourth preset change condition.

[0076] In an embodiment of the present invention, when judging the change situation of the wind speed gear of the indoor fan 13 according to the first wind speed gear D0, the controller 71 is configured to: obtain the current second wind speed gear of the indoor fan 13; if the current second wind speed gear of the indoor fan 13 is consistent with the first wind speed gear D0, it is determined that the change situation of the wind speed gear of the indoor fan 13 meets the fifth preset change condition, otherwise, it is determined that the change situation of the wind speed gear of the indoor fan 13 does not meet the fifth preset change condition.

[0077] Specifically, when judging the change situation of the wind speed gear of the indoor fan 13 according to the first wind speed gear D0, it is further necessary to obtain the current second wind speed gear of the indoor fan 13, for example, denoted as D1, compare the first wind speed gear D0 with the second wind speed gear D1 and judge. If the current second wind speed gear D1 of the indoor fan 13 is consistent with the first wind speed gear D0, that is, D1 = D0, it is determined that the change situation of the wind speed gear of the indoor fan 13 meets the fifth preset change condition. If the current second wind speed gear D1 of the indoor fan 13 is inconsistent with the first wind speed gear D0, that is, D1 ≠ D0, it is determined that the change situation of the wind speed gear of the indoor fan 13 does not meet the fifth preset change condition.

[0078] In an embodiment of the present invention, when judging the change situation of the outdoor environment temperature according to the second outdoor environment temperature Tw0, the controller 71 is configured to: obtain the current third outdoor environment temperature; if the current third outdoor environment temperature is within the preset temperature range, it is determined that the change situation of the outdoor environment temperature meets the sixth preset change condition, otherwise, it is determined that the change situation of the outdoor environment temperature does not meet the sixth preset change condition, where the lower limit value and the upper limit value of the preset temperature range are determined according to the second outdoor environment temperature Tw0, and the third outdoor environment temperature is greater than or equal to the lower limit value of the preset temperature range and less than or equal to the upper limit value of the preset temperature range.

[0079] In the embodiment, when judging the change situation of the outdoor environment temperature according to the second outdoor environment temperature Tw0, it is also necessary to obtain the current third outdoor environment temperature, for example, denoted as Tw1. According to the second outdoor environment temperature Tw0, the lower limit value and the upper limit value of the preset temperature range can be determined. For example, the lower limit value of the preset temperature range is denoted as Tw0 - c, and the upper limit value of the preset temperature range is denoted as Tw0 + c, where c is a specific non - negative value and can be formulated according to the actual situation. For example, c = 1, then the lower limit value of the preset temperature range is Tw0 - 1, and the upper limit value of the preset temperature range is Tw0 + 1. Adding c as the judgment condition of the preset speed range can eliminate the error of initial parameter detection.

[0080] Specifically, if the current third outdoor ambient temperature Tw1 is within a preset temperature range, the third outdoor ambient temperature Tw1 is greater than or equal to the lower limit Tw0-c of the preset temperature range and less than or equal to the upper limit Tw0+c of the preset temperature range, that is, Tw0-c ≤ Tw1 ≤ Tw0+c, it is determined that the change of the outdoor ambient temperature conforms to the sixth preset change condition. If the third outdoor ambient temperature Tw1 is less than the lower limit Tw0-c of the preset temperature range or greater than the upper limit Tw0+c of the preset temperature range, that is, Tw1 < Tw0-c or Tw1 > Tw0+c, it is determined that the change of the outdoor ambient temperature does not conform to the sixth preset change condition.

[0081] According to the air conditioner 10 of the embodiment of the present invention, by setting the first defrost mode and the second defrost mode, and selecting the corresponding defrost mode according to the current corresponding first outdoor ambient temperature and the outdoor coil temperature. When the first outdoor ambient temperature meets the condition for entering the first defrost mode, the execution timing of the defrost operation is determined according to the obtained initial parameters, and / or when it is determined that the air conditioner 10 enters the second defrost mode according to the outdoor coil temperature, the defrost operation is immediately executed, which can avoid the situation of frost formation and non-defrosting of the air conditioner 10, improve the reliability of the unit, and at the same time, can ensure timely defrosting and improve the comfort of users.

[0082] A further embodiment of the present invention also discloses a control method for an air conditioner, which is used for the air conditioner in any of the above embodiments, as Figure 4 shown, the method includes the following steps:

[0083] Step S1: When the air conditioner starts heating operation, obtain the current corresponding first outdoor ambient temperature and the outdoor coil temperature.

[0084] Step S2: Determine whether the air conditioner meets the condition for entering the first defrost mode according to the first outdoor ambient temperature, and / or determine whether the air conditioner meets the condition for entering the second defrost mode according to the outdoor coil temperature.

[0085] Step S3: When it is determined according to the first outdoor ambient temperature that the air conditioner meets the condition for entering the first defrost mode, control the air conditioner to enter the first defrost mode, so as to determine the execution timing of the defrost operation according to the exhaust temperature of the compressor, the opening of the electronic expansion valve, the operating frequency of the compressor, the rotation speed of the outdoor fan, the air volume gear of the indoor fan and the outdoor ambient temperature in the first defrost mode; and / or when it is determined according to the outdoor coil temperature that the air conditioner meets the condition for entering the second defrost mode, control the air conditioner to enter the second defrost mode, so as to immediately execute the defrost operation in the second defrost mode.

[0086] In an embodiment of the present invention, determining whether the air conditioner meets the condition for entering the first defrosting mode according to the first outdoor ambient temperature includes: when it is determined that the first outdoor ambient temperature does not exceed the first preset temperature, determining that the air conditioner meets the condition for entering the first defrosting mode.

[0087] Specifically, reference can be made to Figure 5 to describe the process by which the controller determines whether the air conditioner enters the first defrosting mode. This process includes steps S11 - S15.

[0088] Step S11: The air conditioner starts heating operation.

[0089] Step S12: Obtain the first outdoor ambient temperature.

[0090] Step S13: Determine whether the first outdoor ambient temperature exceeds the first preset temperature. If so, execute Step S14; if not, execute Step S15.

[0091] Step S14: Do not enter the first defrosting mode.

[0092] Step S15: Enter the first defrosting mode.

[0093] In an embodiment of the present invention, when determining the execution timing of the defrosting operation according to the exhaust temperature of the compressor, the opening degree of the electronic expansion valve, the operating frequency of the compressor, the rotation speed of the outdoor fan, the wind speed gear of the indoor fan, and the outdoor ambient temperature in the first defrosting mode, it includes: obtaining the initial parameters corresponding to when the air conditioner enters the first defrosting mode, and the initial parameters include: the first exhaust temperature currently corresponding to the compressor, the first operating frequency currently corresponding to the compressor, the first rotation speed currently corresponding to the outdoor fan, the first wind speed gear currently corresponding to the indoor fan, the first opening degree currently corresponding to the electronic expansion valve, and the second outdoor ambient temperature corresponding to the current outdoor environment; judging the change situation of the exhaust temperature of the compressor according to the first exhaust temperature, if the change situation of the exhaust temperature does not meet the first preset change condition, then return to the step of obtaining the initial parameters corresponding to when the air conditioner enters the first defrosting mode, if the change situation of the exhaust temperature meets the first preset change condition, then judge the change situation of the operating frequency of the compressor according to the first operating frequency; if the change situation of the operating frequency of the compressor does not meet the second preset change condition, then return to the step of obtaining the initial parameters corresponding to when the air conditioner enters the first defrosting mode, if the change situation of the operating frequency of the compressor meets the second preset change condition, then judge the change situation of the opening degree of the electronic expansion valve according to the first opening degree; if the change situation of the opening degree of the electronic expansion valve does not meet the third preset change condition, then return to the step of obtaining the initial parameters corresponding to when the air conditioner enters the first defrosting mode, if the change situation of the opening degree of the electronic expansion valve meets the third preset change condition, then judge the change situation of the rotation speed of the outdoor fan according to the first rotation speed; if the change situation of the rotation speed of the outdoor fan does not meet the fourth preset change condition, then return to the step of obtaining the initial parameters corresponding to when the air conditioner enters the first defrosting mode, if the change situation of the rotation speed of the outdoor fan meets the fourth preset change condition, then judge the change situation of the wind speed gear of the indoor fan according to the first wind speed gear; if the change situation of the wind speed gear of the indoor fan does not meet the fifth preset change condition, then return to the step of obtaining the initial parameters corresponding to when the air conditioner enters the first defrosting mode, if the change situation of the wind speed gear of the indoor fan meets the fifth preset change condition, then judge the change situation of the outdoor ambient temperature according to the second outdoor ambient temperature; if the change situation of the outdoor ambient temperature does not meet the sixth preset change condition, then return to the step of obtaining the initial parameters corresponding to when the air conditioner enters the first defrosting mode, if the change situation of the outdoor ambient temperature meets the sixth preset change condition, then control the air conditioner to execute the defrosting operation.

[0094] Specifically, it is described with reference to Figure 6 the flowchart shown, and this process at least includes step S21-step S35.

[0095] Step S21: Obtain the initial parameters corresponding to when the air conditioner enters the first defrosting mode.

[0096] Step S22: Determine the change in the exhaust temperature of the compressor based on the first exhaust temperature.

[0097] Step S23: Determine whether the change in the exhaust temperature meets the first preset change condition. If so, execute Step S24; if not, execute Step S21.

[0098] Step S24: Determine the change in the operating frequency of the compressor based on the first operating frequency.

[0099] Step S25: Determine whether the change in the operating frequency of the compressor meets the second preset change condition. If so, execute Step S26; if not, execute Step S21.

[0100] Step S26: Determine the change in the opening degree of the electronic expansion valve based on the first opening degree.

[0101] Step S27: Determine whether the change in the opening degree of the electronic expansion valve meets the third preset change condition. If so, execute Step S28; if not, execute Step S21.

[0102] Step S28: Determine the change in the rotational speed of the outdoor fan based on the first rotational speed.

[0103] Step S29: Determine whether the change in the rotational speed of the outdoor fan meets the fourth preset change condition. If so, execute Step S30; if not, execute Step S21.

[0104] Step S30: Determine the change in the wind speed gear of the indoor fan based on the first wind speed gear.

[0105] Step S31: Determine whether the change in the wind speed gear of the indoor fan meets the fifth preset change condition. If so, execute Step S32; if not, execute Step S21.

[0106] Step S32: Determine the change in the indoor environment temperature based on the second outdoor environment temperature.

[0107] Step S33: Determine whether the change in the outdoor environment temperature meets the sixth preset change condition. If so, execute Step S34; if not, execute Step S21.

[0108] Step S34: Control the air conditioner to perform a defrosting operation.

[0109] Step S35: After defrosting is completed, stop executing the defrosting operation and exit the first defrosting mode.

[0110] In an embodiment of the present invention, when judging the change of the exhaust temperature of the compressor according to the first exhaust temperature, it includes: obtaining the exhaust temperature of the compressor once every first preset time to obtain multiple groups of exhaust temperatures; when the multiple groups of exhaust temperatures decrease in sequence and are all less than the first exhaust temperature, and the difference between the first exhaust temperature and the last one of the multiple groups of exhaust temperatures is greater than or equal to a preset value, it is determined that the change of the exhaust temperature meets the first preset change condition, otherwise, it is determined that the change of the exhaust temperature does not meet the first preset change condition.

[0111] In an embodiment of the present invention, when judging the change of the operating frequency of the compressor according to the first operating frequency, it includes: obtaining the current second operating frequency of the compressor; if the current second operating frequency of the compressor is greater than or equal to the first operating frequency, it is determined that the change of the operating frequency of the compressor meets the second preset change condition, otherwise, it is determined that the change of the operating frequency of the compressor does not meet the second preset change condition.

[0112] In an embodiment of the present invention, when judging the change of the opening of the electronic expansion valve according to the first opening, it includes: obtaining the current second opening of the electronic expansion valve; if the current second opening of the electronic expansion valve is less than or equal to the first opening, it is determined that the change of the opening of the electronic expansion valve meets the third preset change condition, otherwise, it is determined that the change of the opening of the electronic expansion valve does not meet the third preset change condition.

[0113] In an embodiment of the present invention, when judging the change of the rotational speed of the outdoor fan according to the first rotational speed, it includes: obtaining the current second rotational speed of the outdoor fan; if the current second rotational speed of the outdoor fan is within a preset rotational speed range, it is determined that the change of the rotational speed of the outdoor fan meets the fourth preset change condition, otherwise, it is determined that the change of the rotational speed of the outdoor fan does not meet the fourth preset change condition, where the lower limit value and the upper limit value of the preset rotational speed range are determined according to the first rotational speed, and the second rotational speed is greater than or equal to the lower limit value of the preset rotational speed range and less than or equal to the upper limit value of the preset rotational speed range.

[0114] In an embodiment of the present invention, when judging the change of the wind speed gear of the indoor fan according to the first wind speed gear, it includes: obtaining the current second wind speed gear of the indoor fan; if the current second wind speed gear of the indoor fan is the same as the first wind speed gear, it is determined that the change of the wind speed gear of the indoor fan meets the fifth preset change condition, otherwise, it is determined that the change of the wind speed gear of the indoor fan does not meet the fifth preset change condition.

[0115] In an embodiment of the present invention, when determining the change of the outdoor ambient temperature according to the second outdoor ambient temperature, it includes: obtaining the current third outdoor ambient temperature; if the current third outdoor ambient temperature is within a preset temperature range, it is determined that the change of the outdoor ambient temperature meets the sixth preset change condition, otherwise, it is determined that the change of the outdoor ambient temperature does not meet the sixth preset change condition, wherein the lower limit value and the upper limit value of the preset temperature range are determined according to the second outdoor ambient temperature, and the third outdoor ambient temperature is greater than or equal to the lower limit value of the preset temperature range and less than or equal to the upper limit value of the preset temperature range.

[0116] Specifically, reference can be made to Figure 7 The control method of the air conditioner is described in detail, and this method at least includes step S40 - step S60.

[0117] Step S40: The air conditioner starts heating operation and the air conditioner meets the conditions for entering the first defrosting mode.

[0118] Step S41: Obtain the initial parameters corresponding to when the air conditioner enters the first defrosting mode.

[0119] Step S42: Obtain the discharge temperature of the compressor once every first preset time to obtain multiple groups of discharge temperatures.

[0120] Step S43: Determine whether the multiple groups of discharge temperatures decrease in sequence and are all less than the first discharge temperature, and whether the difference between the first discharge temperature and the last one of the multiple groups of discharge temperatures is greater than or equal to a preset value. If so, execute step S44; if not, execute step S41.

[0121] Step S44: Determine that the change of the discharge temperature meets the first preset change condition.

[0122] Step S45: Obtain the current second operating frequency of the compressor.

[0123] Step S46: Determine whether the current second operating frequency of the compressor is greater than or equal to the first operating frequency. If so, execute step S47; if not, execute step S41.

[0124] Step S47: Determine that the change of the operating frequency of the compressor meets the second preset change condition.

[0125] Step S48: Obtain the current second opening degree of the electronic expansion valve.

[0126] Step S49: Determine whether the current second opening degree of the electronic expansion valve is less than or equal to the first opening degree. If so, execute step S50; if not, execute step S41.

[0127] Step S50: Determine that the change of the opening degree of the electronic expansion valve meets the third preset change condition.

[0128] Step S51: Obtain the current second rotational speed of the outdoor fan.

[0129] Step S52: Determine whether the current second rotational speed of the outdoor fan is within a preset rotational speed range. If so, execute Step S53; if not, execute Step S41.

[0130] Step S53: Determine that the change in the rotational speed of the outdoor fan conforms to a fourth preset change condition.

[0131] Step S54: Obtain the current second air volume gear of the indoor fan.

[0132] Step S55: Determine whether the current second air volume gear of the indoor fan is the same as the first air volume gear. If so, execute Step S56; if not, execute Step S41.

[0133] Step S56: Determine that the change in the air volume gear of the indoor fan conforms to a fifth preset change condition.

[0134] Step S57: Obtain the current third outdoor ambient temperature.

[0135] Step S58: Determine whether the current third outdoor ambient temperature is within a preset temperature range. If so, execute Step S59; if not, execute Step S41.

[0136] Step S59: Determine that the change in the outdoor ambient temperature conforms to a sixth preset change condition.

[0137] Step S60: Control the air conditioner to perform a defrosting operation.

[0138] According to the control method of the air conditioner in the embodiment of the present invention, by setting a first defrosting mode and a second defrosting mode, selecting a corresponding defrosting mode according to the current corresponding first outdoor ambient temperature and the outdoor coil temperature, when the first outdoor ambient temperature meets the condition for entering the first defrosting mode, determining the execution timing of the defrosting operation according to the obtained initial parameters, and / or immediately performing the defrosting operation after determining that the air conditioner enters the second defrosting mode according to the outdoor coil temperature, it is possible to avoid the situation of frost formation and non - defrosting of the air conditioner, improve the reliability of the unit, and at the same time, ensure timely defrosting and improve the comfort of users.

[0139] It should be noted that when controlling the air conditioner, the specific implementation manner of the control method of the air conditioner in the embodiment of the present invention is similar to the specific implementation manner of the air conditioner in the embodiment of the present invention. For details, please refer to the description of the air conditioner part. To reduce redundancy, it will not be elaborated here.

[0140] In the description of this specification, the description with reference to terms such as "one embodiment", "some embodiments", "schematic embodiments", "examples", "specific examples", or "some examples" means that the specific features, structures, materials, or characteristics described in connection with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example.

[0141] Although the embodiments of the present invention have been shown and described, those of ordinary skill in the art can understand that various changes, modifications, substitutions, and variations can be made to these embodiments without departing from the principles and spirit of the present invention. The scope of the present invention is defined by the claims and their equivalents.

Claims

1. An air conditioner, characterized in that: include: A refrigerant circulation loop, wherein the refrigerant performs a refrigeration cycle in a loop consisting of a compressor, a condenser, an expansion valve, and an evaporator, wherein one of the condenser and the evaporator is an outdoor heat exchanger and the other is an indoor heat exchanger; an electronic expansion valve, disposed between the condenser and the evaporator, the electronic expansion valve being used to increase the flow resistance of the refrigerant passing through the electronic expansion valve when the opening degree of the electronic expansion valve is reduced, and to reduce the flow resistance of the refrigerant passing through the electronic expansion valve when the opening degree of the electronic expansion valve is increased; An indoor fan, used to drive the indoor air to pass through the indoor heat exchanger by rotating, so that the refrigerant and the indoor air can exchange heat; An outdoor fan is used to drive outdoor air to pass through the outdoor heat exchanger by rotating so that the refrigerant and the outdoor air can exchange heat; An exhaust temperature sensor, used to detect the exhaust temperature of the compressor; Outdoor ambient temperature sensor, used to detect outdoor ambient temperature; Outdoor coil temperature sensor, used to detect outdoor coil temperature; A controller, the controller being configured to: when the air conditioner is turned on for heating operation, obtain a current corresponding first outdoor ambient temperature and the outdoor coil temperature; Determining whether the air conditioner meets the condition of entering a first defrost mode according to the first outdoor ambient temperature, and / or determining whether the air conditioner meets the condition of entering a second defrost mode according to the outdoor coil temperature; When it is determined according to the first outdoor ambient temperature that the air conditioner meets the condition for entering the first defrost mode, the air conditioner is controlled to enter the first defrost mode, so that in the first defrost mode, the execution timing of the defrost action is determined according to the exhaust temperature of the compressor, the opening of the electronic expansion valve, the operating frequency of the compressor, the rotation speed of the outdoor fan, the wind speed gear of the indoor fan and the outdoor ambient temperature; And / or when it is determined according to the outdoor coil temperature that the air conditioner meets the condition for entering the second defrost mode, the air conditioner is controlled to enter the second defrost mode, so as to immediately perform the defrost action in the second defrost mode.

2. The air conditioner according to claim 1, characterized in that: When judging whether the air conditioner meets the condition of entering the first defrost mode according to the first outdoor ambient temperature, the controller is configured as follows: When it is determined that the first outdoor environment temperature does not exceed the first preset temperature, it is determined that the air conditioner meets the condition of entering the first defrost mode.

3. The air conditioner according to claim 1, characterized in that: In the first defrost mode, when determining the execution timing of the defrost action according to the exhaust temperature of the compressor, the opening of the electronic expansion valve, the operating frequency of the compressor, the speed of the outdoor fan, the wind speed gear of the indoor fan and the outdoor ambient temperature, the controller is configured as follows: Acquire initial parameters corresponding to when the air conditioner enters the first defrost mode, the initial parameters including: a first exhaust temperature currently corresponding to the compressor, a first operating frequency currently corresponding to the compressor, a first speed currently corresponding to the outdoor fan, a first wind speed gear currently corresponding to the indoor fan, a first opening currently corresponding to the electronic expansion valve, and a second outdoor environment temperature corresponding to the current outdoor environment; judging the change of the exhaust temperature of the compressor according to the first exhaust temperature, and if the change of the exhaust temperature does not meet the first preset change condition, returning to the step of obtaining the initial parameters corresponding to when the air conditioner enters the first defrost mode, and if the change of the exhaust temperature meets the first preset change condition, judging the change of the operating frequency of the compressor according to the first operating frequency; If the change in the operating frequency of the compressor does not meet the second preset change condition, returning to the step of obtaining the initial parameters corresponding to when the air conditioner enters the first defrost mode, and if the change in the operating frequency of the compressor meets the second preset change condition, judging the change in the opening of the electronic expansion valve according to the first opening; If the change in the opening of the electronic expansion valve does not meet the third preset change condition, returning to the step of obtaining the initial parameters corresponding to when the air conditioner enters the first defrost mode, and if the change in the opening of the electronic expansion valve meets the third preset change condition, determining the change in the speed of the outdoor fan according to the first speed; If the speed change of the outdoor fan does not meet the fourth preset change condition, return to the step of obtaining the initial parameters corresponding to when the air conditioner enters the first defrost mode, and if the speed change of the outdoor fan meets the fourth preset change condition, determine the wind speed gear change of the indoor fan according to the first wind speed gear; If the wind speed level change of the indoor fan does not meet the fifth preset change condition, return to the step of obtaining the initial parameters corresponding to when the air conditioner enters the first defrost mode, and if the wind speed level change of the indoor fan meets the fifth preset change condition, determine the change of the outdoor ambient temperature according to the second outdoor ambient temperature; If the change in the outdoor ambient temperature does not meet the sixth preset change condition, return to the step of obtaining the initial parameters corresponding to when the air conditioner enters the first defrost mode. If the change in the outdoor ambient temperature meets the sixth preset change condition, control the air conditioner to perform the defrost action.

4. The air conditioner according to claim 3, characterized in that: When judging the change of the exhaust gas temperature of the compressor according to the first exhaust gas temperature, the controller is configured as follows: Acquiring the exhaust temperature of the compressor once at a first preset time interval to obtain multiple groups of exhaust temperatures; When the multiple groups of exhaust temperatures decrease successively and are all lower than the first exhaust temperature, and the difference between the first exhaust temperature and the last one of the multiple groups of exhaust temperatures is greater than or equal to a preset value, it is determined that the change in the exhaust temperature meets the first preset change condition; otherwise, it is determined that the change in the exhaust temperature does not meet the first preset change condition.

5. The air conditioner according to claim 3, characterized in that: When determining a change in the operating frequency of the compressor according to the first operating frequency, the controller is configured to: Acquire a current second operating frequency of the compressor; If the current second operating frequency of the compressor is greater than or equal to the first operating frequency, it is determined that the change in the operating frequency of the compressor meets the second preset change condition; otherwise, it is determined that the change in the operating frequency of the compressor does not meet the second preset change condition.

6. The air conditioner according to claim 3, characterized in that: When judging the change of the opening degree of the electronic expansion valve according to the first opening degree, the controller is configured as follows: Acquire the current second opening degree of the electronic expansion valve; If the current second opening of the electronic expansion valve is less than or equal to the first opening, it is determined that the change in the opening of the electronic expansion valve meets the third preset change condition; otherwise, it is determined that the change in the opening of the electronic expansion valve does not meet the third preset change condition.

7. The air conditioner according to claim 3, characterized in that: When determining the change in the speed of the outdoor fan according to the first speed, the controller is configured as follows: Obtaining a current second speed of the outdoor fan; If the current second speed of the outdoor fan is in the preset speed range, it is determined that the speed change of the outdoor fan meets the fourth preset change condition; otherwise, it is determined that the speed change of the outdoor fan does not meet the fourth preset change condition, wherein the lower limit value and the upper limit value of the preset speed range are determined according to the first speed, and the second speed is greater than or equal to the lower limit value of the preset speed range, and less than or equal to the upper limit value of the preset speed range.

8. The air conditioner according to claim 3, characterized in that: When determining the change of the wind speed level of the indoor fan according to the first wind speed level, the controller is configured as follows: Obtaining the current second wind speed gear of the indoor fan; If the current second wind speed level of the indoor fan is consistent with the first wind speed level, it is determined that the wind speed level change of the indoor fan meets the fifth preset change condition; otherwise, it is determined that the wind speed level change of the indoor fan does not meet the fifth preset change condition.

9. The air conditioner according to claim 3, characterized in that: When determining a change in the outdoor ambient temperature according to the second outdoor ambient temperature, the controller is configured to: Get the current third outdoor ambient temperature; If the current third outdoor ambient temperature is within the preset temperature range, it is determined that the change in the outdoor ambient temperature meets the sixth preset change condition; otherwise, it is determined that the change in the outdoor ambient temperature does not meet the sixth preset change condition, wherein the lower limit value and the upper limit value of the preset temperature range are determined according to the second outdoor ambient temperature, and the third outdoor ambient temperature is greater than or equal to the lower limit value of the preset temperature range, and less than or equal to the upper limit value of the preset temperature range.

10. A method for controlling an air conditioner, characterized in that: For the air conditioner according to any one of claims 1 to 9, the method comprises the following steps: When the air conditioner is turned on for heating operation, obtaining the current corresponding first outdoor ambient temperature and the outdoor coil temperature; Determining whether the air conditioner meets the condition of entering a first defrost mode according to the first outdoor ambient temperature, and / or determining whether the air conditioner meets the condition of entering a second defrost mode according to the outdoor coil temperature; When it is determined according to the first outdoor ambient temperature that the air conditioner meets the conditions for entering the first defrost mode, the air conditioner is controlled to enter the first defrost mode, so that in the first defrost mode, the timing of executing the defrost action is determined according to the exhaust temperature of the compressor, the opening of the electronic expansion valve, the operating frequency of the compressor, the speed of the outdoor fan, the wind speed gear of the indoor fan and the outdoor ambient temperature; and / or when it is determined according to the outdoor coil temperature that the air conditioner meets the conditions for entering the second defrost mode, the air conditioner is controlled to enter the second defrost mode, so that in the second defrost mode, the defrost action is immediately performed.

Images