Air conditioner and control method thereof

Abstract

The embodiment of the application discloses an air conditioner and a control method thereof, relates to the technical field of air conditioners, and is used for realizing different defrosting strategies of an outdoor heat exchanger at different frost formation degrees. The air conditioner comprises: a refrigerant circulation loop, which enables refrigerant to circulate in a loop formed by a compressor, an outdoor heat exchanger, a waterside heat exchanger, an expansion valve and a four-way valve; the outdoor heat exchanger is a fin heat exchanger; a first temperature sensor is used for detecting an ambient temperature; a second temperature sensor is arranged on the outdoor heat exchanger and is used for detecting the temperature of the outdoor heat exchanger; and a controller is configured to: acquire the ambient temperature detected by the first temperature sensor and the temperature of the outdoor heat exchanger detected by the second temperature sensor; determine a target defrosting strategy of the outdoor heat exchanger from a plurality of defrosting strategies based on the ambient temperature and the temperature of the outdoor heat exchanger; and control the air conditioner to execute the target defrosting strategy.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of air conditioners, and in particular to an air conditioner and a control method thereof. BACKGROUND

[0002] The finned heat exchanger in an air conditioner is the most widely used heat exchange equipment in gas-liquid heat exchangers. It achieves the purpose of heat transfer enhancement by adding fins to ordinary base pipes. Defrosting is a function of the finned heat exchanger. However, the degree of frosting of the finned heat exchanger of the unit varies in different regions, different ambient temperatures, different humidity, and even different configurations of the unit.

[0003] If a simple fixed duration, fixed ring fin temperature difference, and other ordinary methods are used to determine the defrosting program, it is easy to cause problems such as false defrosting and incomplete defrosting. In some extreme cases, due to too much frosting, the compressor is empty for a long time during the start-up stage after defrosting, and the compressor is seriously damaged.

[0004] How to judge the frosting condition of the unit under various complex situations and adjust the defrosting strategy accordingly to ensure that the unit can be safely and reliably defrosted under various working conditions without problems such as emptying and incomplete defrosting is a difficult problem faced by the industry. SUMMARY

[0005] The present application provides an air conditioner and a control method thereof, which are used to realize different defrosting strategies of an outdoor heat exchanger under different frosting degrees.

[0006] In order to achieve the above-mentioned purpose, the present application adopts the following technical solutions.

[0007] In a first aspect, the present application provides an air conditioner, which comprises: a refrigerant circulation loop, which enables refrigerant to circulate in a loop composed of a compressor, an outdoor heat exchanger, a water-side heat exchanger, an expansion valve, and a four-way valve; the outdoor heat exchanger is a finned heat exchanger; the outdoor heat exchanger and the water-side heat exchanger, wherein one functions as a condenser and the other functions as an evaporator; a first temperature sensor for detecting the ambient temperature; a second temperature sensor arranged on the outdoor heat exchanger for detecting the temperature of the outdoor heat exchanger; a controller configured to: obtain the ambient temperature detected by the first temperature sensor and the temperature of the outdoor heat exchanger detected by the second temperature sensor; determine a target defrosting strategy of the outdoor heat exchanger from a plurality of defrosting strategies based on the ambient temperature and the temperature of the outdoor heat exchanger; wherein different defrosting strategies in the plurality of defrosting strategies are used to cope with different frosting degrees of the outdoor heat exchanger, each defrosting strategy includes temperature conditions for the air conditioner to enter a defrosting period, interval duration between adjacent two defrosting periods, expansion valve opening degree, and switching time of the four-way valve after the end of the defrosting period; and control the air conditioner to execute the target defrosting strategy.

[0008] The technical solution provided in this application provides at least the following beneficial effects: This solution sets up multiple defrosting strategies to address different degrees of frost on the outdoor heat exchanger. By comparing the ambient temperature and the outdoor heat exchanger temperature, the appropriate target defrosting strategy for the outdoor heat exchanger is determined from among these multiple strategies. This enables the outdoor heat exchanger to employ different target defrosting strategies under different frost levels, and adjusts the air conditioner's operating parameters based on these different target defrosting strategies. This ensures stable compressor operation during and after the defrosting cycle, avoiding problems such as compressor oil depletion, false defrosting, and incomplete defrosting caused by excessive refrigerant flashover during four-way valve switching. Thus, targeted, reasonable, and reliable defrosting of the air conditioner is achieved.

[0009] In some embodiments, the multiple defrosting strategies include a first defrosting strategy, a second defrosting strategy, and a third defrosting strategy; wherein the degree of frost on the outdoor heat exchanger addressed by the first defrosting strategy, the second defrosting strategy, and the third defrosting strategy increases sequentially.

[0010] In some embodiments, the controller is specifically configured to: determine the target defrosting strategy as the first defrosting strategy when the ambient temperature is not within a preset ambient temperature range.

[0011] In some embodiments, the controller is specifically configured to: when the ambient temperature is within a preset ambient temperature range, and the outdoor heat exchanger temperature satisfies a*T with the ambient temperature. a +b>T e >a*T a When +bc is applied, the target defrosting strategy is determined to be the second defrosting strategy; where T e The outdoor heat exchanger temperature, T a The ambient temperature is given, and a and b are constants.

[0012] In some embodiments, the controller is specifically configured to: when the ambient temperature is within a preset ambient temperature range, and the outdoor heat exchanger temperature satisfies T... e ≤a*T a When +bc is used, the target defrosting strategy is determined to be the third defrosting strategy.

[0013] In some embodiments, for the first defrosting strategy, the temperature condition for the air conditioner to enter the defrosting cycle satisfies T. e <a*T a +b, the interval between two adjacent defrosting cycles is the first duration, the expansion valve opening is the first opening, and the switching time of the four-way valve after the end of the defrosting cycle is the time after the first time interval after the end of the defrosting cycle.

[0014] In some embodiments, for the second defrosting strategy, the temperature condition for the air conditioner to enter the defrosting cycle satisfies T e <a*T a +b, the interval time between the adjacent two defrosting cycles is a second interval time, the opening degree of the expansion valve is a second opening degree, and the switching time of the four-way valve after the end of the defrosting cycle is a time after a second time interval after the end of the defrosting cycle; the second interval time is less than the first interval time; the second opening degree is less than the first opening degree, and the second time interval is less than the first time interval.

[0015] In some embodiments, for the third defrosting strategy, the temperature condition for the air conditioner to enter the defrosting cycle satisfies T e <a*T a +b-c, the interval time between the adjacent two defrosting cycles is a third interval time, the opening degree of the expansion valve is a third opening degree, and the switching time of the four-way valve after the end of the defrosting cycle is a time after a third time interval after the end of the defrosting cycle; the third interval time is less than the second interval time, the third opening degree is less than the second opening degree, and the third time interval is less than the second time interval.

[0016] In a second aspect, the embodiments of the present application provide a control method of an air conditioner, the method comprising: obtaining an ambient temperature and an outdoor heat exchanger temperature; determining a target defrosting strategy of the outdoor heat exchanger from a plurality of defrosting strategies based on the ambient temperature and the outdoor heat exchanger temperature, different defrosting strategies in the plurality of defrosting strategies being used to cope with different frosting degrees of the outdoor heat exchanger; and controlling the air conditioner to operate with defrosting parameters in the target defrosting strategy, the defrosting parameters comprising target operating parameters of the air conditioner, including: a temperature condition for the air conditioner to enter a defrosting cycle, an interval time between adjacent two defrosting cycles, an opening degree of an expansion valve, and a switching time of a four-way valve after the end of the defrosting cycle.

[0017] In a third aspect, the embodiments of the present application provide a controller, comprising: one or more processors; and one or more memories; wherein the one or more memories are configured to store computer program codes, the computer program codes comprising computer instructions, and when the one or more processors execute the computer instructions, the controller performs any of the control methods of the air conditioner provided in the second aspect.

[0018] In a fourth aspect, the embodiments of the present application provide a computer readable storage medium, the computer readable storage medium comprising computer instructions, and when the computer instructions are executed on a computer, the computer instructions cause the computer to perform the method provided in the second aspect and possible implementation manners.

[0019] In a fifth aspect, the embodiments of the present application provide a computer program product, the computer program product being directly loadable into a memory and containing software codes, and the computer program product, when loaded and executed by a computer, can realize the method provided in the second aspect and possible implementation manners.

[0020] It should be noted that the above computer instructions can be stored in whole or in part on a computer readable storage medium. The computer readable storage medium can be packaged together with the processor of the controller or packaged separately from the processor of the controller, and the present application does not limit this.

[0021] The beneficial effects of the second aspect to the fifth aspect described in the present application can be analyzed with reference to the beneficial effects of the first aspect, which will not be repeated here. BRIEF DESCRIPTION OF DRAWINGS

[0022] The accompanying drawings are included to provide a further understanding of the technical solutions of the present application, and constitute a part of the specification, and are used together with the embodiments of the present application to explain the technical solutions of the present application, and do not constitute a limitation on the technical solutions of the present application.

[0023] Figure 1 A schematic diagram of the composition of an air conditioner provided for the embodiments of the present application is provided;

[0024] Figure 2 A schematic block diagram of the structure of an air conditioner provided for the embodiments of the present application is provided;

[0025] Figure 3 A schematic block diagram of the structure of another air conditioner provided for the embodiments of the present application is provided;

[0026] Figure 4 A schematic diagram of the refrigeration cycle principle of an air conditioner provided for the embodiments of the present application is provided;

[0027] Figure 5 A schematic diagram of the refrigerant flow direction of an air conditioner provided for the embodiments of the present application is provided;

[0028] Figure 6 A hardware configuration block diagram of an air conditioner provided for the embodiments of the present application is provided;

[0029] Figure 7 A control method flowchart of an air conditioner provided for the embodiments of the present application is provided;

[0030] Figure 8 A schematic diagram of the relationship between a target defrosting strategy and a frost degree provided for the embodiments of the present application is provided;

[0031] Figure 9 A control method flowchart of another air conditioner provided for the embodiments of the present application is provided;

[0032] Figure 10 A hardware structure schematic diagram of a controller provided for the embodiments of the present application is provided. DETAILED DESCRIPTION

[0033] With reference to the drawings and the embodiments of the present application, the technical solutions in the embodiments of the present application will be clearly and completely described. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all the embodiments of the present application. Based on the embodiments of the present application, all other embodiments obtained by those of ordinary skill in the art without creative efforts are within the scope of the present application.

[0034] It should be noted that all directional indications, such as upper, lower, left, right, front, back, etc., are only used to explain the relative position relationship, movement condition, etc. between components in a certain posture (as shown in the drawings), and if the certain posture changes, the directional indications also change accordingly.

[0035] The terms "first", "second", etc. are only used for description purpose, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined with "first", "second" can explicitly or implicitly include one or more of the features. In the description of the present application, unless otherwise specified, the meaning of "a plurality of" is two or more.

[0036] In the description of the present application, it should be noted that, unless otherwise specified and limited, the terms "connected", "connection" should be understood in a broad sense, for example, can be fixed connection, can also be detachable connection, or integrally connected. For those of ordinary skill in the art, the specific meaning of the above terms in the present application can be understood according to the specific circumstances. In addition, when describing the pipeline, the "connected" and "connected" used in the present application have the meaning of conducting. The specific meaning needs to be understood in combination with the context.

[0037] In the embodiments of the present application, the words such as "exemplary" or "for example" are used to represent as an example, illustration or description. Any embodiment or design scheme described as "exemplary" or "for example" in the embodiments of the present application should not be interpreted as more preferred or more advantageous than other embodiments or design schemes. Rather, the words such as "exemplary" or "for example" are intended to present the relevant concept in a specific manner.

[0038] In the related art, the frost degree of the air conditioner under complex situation is not comprehensive, and the defrosting strategy cannot be adjusted accordingly, so that the problems of compressor oil emptying and unclean defrosting occur.

[0039] Based on this, the embodiment of the present application provides an air conditioner, which comprises: a refrigerant circulation loop, which enables refrigerant to circulate in a loop composed of a compressor, an outdoor heat exchanger, a water-side heat exchanger, an expansion valve and a four-way valve; the outdoor heat exchanger is a fin heat exchanger; the outdoor heat exchanger and the water-side heat exchanger, wherein one is a condenser and the other is an evaporator; a first temperature sensor for detecting the ambient temperature; a second temperature sensor arranged on the outdoor heat exchanger for detecting the outdoor heat exchanger temperature; a controller configured to: obtain the ambient temperature detected by the first temperature sensor and the outdoor heat exchanger temperature detected by the second temperature sensor; determine the target defrosting strategy of the outdoor heat exchanger from a plurality of defrosting strategies based on the ambient temperature and the outdoor heat exchanger temperature; wherein different defrosting strategies in the plurality of defrosting strategies are used to cope with different frosting degrees of the outdoor heat exchanger, and each defrosting strategy includes the temperature condition of the air conditioner entering the defrosting cycle, the interval time between two adjacent defrosting cycles, the opening degree of the expansion valve and the switching time of the four-way valve after the end of the defrosting cycle; and control the air conditioner to execute the target defrosting strategy.

[0040] In this way, the air conditioner adjusts the operating parameters of the air conditioner according to different target defrosting strategies, and ensures the stable operation of the compressor during and after defrosting.

[0041] The embodiments provided by the present application will be described in detail below with reference to the accompanying drawings.

[0042] Figure 1 An example of an air conditioner provided by the embodiment of the present application is shown in the accompanying drawings, which comprises an outdoor unit 11, a throttling device 12 (not shown in the drawings), an indoor unit 13, and a controller 1000 (not shown in the drawings). Figure 1 Figure 1 The indoor unit 13, taking an indoor hanging machine (shown in the drawings) as an example, is usually installed on the indoor wall surface or the like. For another example, an indoor cabinet machine (not shown in the drawings) is also a kind of indoor machine form of the indoor machine. Figure 1

[0043] The outdoor unit 11 is usually arranged outdoors and is used for outdoor environment heat exchange. In addition, in the drawings, the outdoor unit 11 is represented by a dashed line because it is located on the opposite side of the indoor unit 13 through the wall surface. Figure 1 Figure 1

[0044] The outdoor unit 11 is usually arranged outdoors and is used for outdoor environment heat exchange. In addition, in the drawings, the outdoor unit 11 is represented by a dashed line because it is located on the opposite side of the indoor unit 13 through the wall surface. Figure 1

[0045] ​​​​​The throttling device 12 includes an expansion valve 121. The outdoor unit 11 is connected to the indoor unit 13 by a pipe, and the pipe between the indoor unit 13 and the outdoor unit 11 is provided with the expansion valve 121. The pipe, i.e., a gas-liquid pipe, includes a gas pipe for conveying gaseous refrigerant and a liquid pipe for conveying two-phase refrigerant.

[0046] The throttling device 12 is configured to adjust the flow rate of fluid in the gas-liquid pipe of the air conditioner and to adjust the flow of refrigerant. The expansion valve 121 is configured to adjust the amount of refrigerant supplied in the pipe. Figure 2 A structural schematic diagram of an air conditioner according to an exemplary embodiment is provided in the present application, as shown in Figure 2 The expansion valve 121 can be independent of the outdoor unit 11, or can be part of the outdoor unit 11 (as shown in Figure 3 ). Figure 3 A structural schematic diagram of another air conditioner according to an exemplary embodiment is provided in the present application.

[0047] In addition, the outdoor unit 11, the throttling device 12, and the indoor unit 13 are all in communication connection with the controller 1000 (not shown in Figure 1 ), and perform relevant operations according to the instructions of the controller 1000.

[0048] Taking the case where the expansion valve 121 is part of the outdoor unit 11, Figure 4 A schematic diagram of the refrigeration cycle of an air conditioner is shown. As shown in Figure 4 The air conditioner 10 includes an outdoor unit 11, a throttling device 12, an indoor unit 13, and a controller 1000 (not shown in Figure 4 ).

[0049] The outdoor unit 11 includes a compressor 111, an outdoor heat exchanger 112, a gas-liquid separator 113, and a four-way valve 114. In some embodiments, the outdoor unit 11 further includes one or more of the following: an outdoor fan (not shown in Figure 4 ), and an outdoor fan motor (not shown in Figure 4 ).

[0050] In some embodiments, the throttling device 12 is configured to adjust the flow rate of fluid in the gas pipe and the liquid pipe of the air conditioner 10.

[0051] In some embodiments, the compressor 111 is disposed between the throttling device 12 and the gas-liquid separator 113, and is configured to compress the refrigerant delivered by the gas-liquid separator 113 and to deliver the compressed refrigerant to the throttling device 12 via the four-way valve 114. The compressor 111 can be an inverter compressor with variable capacity based on inverter-based speed control.

[0052] In some embodiments, one end of the outdoor heat exchanger 112 is connected to the gas-liquid separator 113 via the four-way valve 114, and the other end is connected to the throttling device 12. The outdoor heat exchanger 112 has a first port for passing the refrigerant between the outdoor heat exchanger 112 and the suction port of the compressor 111 via the gas-liquid separator 113, and has a second port for passing the refrigerant between the outdoor heat exchanger 112 and the throttling device 12. The outdoor heat exchanger 112 exchanges heat between the outdoor air and the hot refrigerant flowing in the heat transfer pipe connected between the first port and the second port, and functions as a condenser in the refrigeration cycle.

[0053] In some embodiments, one end of the gas-liquid separator 113 is connected to the compressor 111, and the other end is connected to the four-way valve 114 and the outdoor heat exchanger 112. In the gas-liquid separator 113, the refrigerant flowing from the outdoor heat exchanger 112 to the compressor 111 via the four-way valve 114 is separated into gaseous refrigerant and liquid refrigerant. And, mainly gaseous refrigerant is supplied to the suction port of the compressor 111 from the gas-liquid separator 113.

[0054] In some embodiments, the four ports of the four-way valve 114 are connected to the compressor 111, the outdoor heat exchanger 112, and the gas-liquid separator 113, respectively. The four-way valve 114 is used to achieve mutual conversion between refrigeration and heating by changing the flow direction of the refrigerant in the system pipeline.

[0055] In some embodiments, the outdoor fan is used to generate air flow of the outdoor air passing through the outdoor heat exchanger 112, so as to promote heat exchange between the refrigerant flowing in the heat transfer pipe between the first port and the second port and the outdoor air.

[0056] In some embodiments, the outdoor fan motor is used to drive or change the rotating speed of the outdoor fan.

[0057] In some embodiments, the expansion valve 121 has the function of expanding and reducing the pressure of the refrigerant flowing through the expansion valve 121, and can be used to adjust the supply amount of the refrigerant in the pipeline. If the opening degree of the expansion valve 121 is reduced, the flow path resistance of the refrigerant passing through the expansion valve 121 is increased. If the opening degree of the expansion valve 121 is increased, the flow path resistance of the refrigerant passing through the expansion valve 121 is reduced. In this way, even if the states of other devices in the circuit do not change, when the opening degree of the expansion valve 121 changes, the refrigerant flow to the indoor unit 13 will also change.

[0058] In some embodiments, the indoor unit 13 includes a water-side heat exchanger 131 and an indoor fan 133 (not shown in the figure). In some embodiments, the indoor unit 13 further includes an indoor fan motor (not shown in the figure). Figure 4 Figure 4 In some embodiments, the indoor unit 13 includes a water-side heat exchanger 131 and an indoor fan 133 (not shown in the figure). In some embodiments, the indoor unit 13 further includes an indoor fan motor (not shown in the figure).

[0059] ​In some embodiments, the water-side heat exchanger 131 has a third port for passing liquid refrigerant between the expansion valve 121, and a fourth port for passing gaseous refrigerant between the discharge port of the compressor 111. The water-side heat exchanger 131 exchanges heat between the refrigerant flowing in the heat transfer pipe connected between the third port and the fourth port, and the indoor air.

[0060] In some embodiments, the indoor fan 133 generates an air flow of the indoor air through the water-side heat exchanger 131 to facilitate heat exchange between the refrigerant flowing in the heat transfer pipe between the third port and the fourth port, and the indoor air.

[0061] In some embodiments, the indoor fan motor is used to drive or change the rotation speed of the indoor fan 133.

[0062] In the embodiments shown in the present application, the controller 1000 refers to a device that can generate operation control signals according to instruction operation codes and timing signals, and instruct the air conditioner 10 to execute control instructions. For example, the controller 1000 can be a central processing unit (CPU), a general processor network processor (NP), a digital signal processing (DSP), a microprocessor, a microcontroller, a programmable logic device (PLD), or any combination thereof. The controller 1000 can also be other devices with processing functions, such as circuits, devices, or software modules, and the embodiments of the present application do not make any limitation thereto.

[0063] In addition, the controller 1000 can be used to control the components in the air conditioner 10 to make the components operate to achieve the predetermined functions of the air conditioner 10.

[0064] In some embodiments, the air conditioner 10 is also attached with a remote controller, which has a function of communicating with the controller 1000, for example, using infrared or other communication methods. The remote controller is used for the user to control various controls of the air conditioner, to achieve the interaction between the user and the air conditioner 10.

[0065] Figure 5 A schematic diagram of the refrigerant flow direction of an air conditioner according to an exemplary embodiment of the present application.

[0066] In some embodiments, when the air conditioner is in the cooling mode, the d end and the c end of the four-way valve 114 are connected, and the e end and the s end are connected. At this time, the outdoor heat exchanger 112 acts as a condenser, and the water-side heat exchanger 131 acts as an evaporator. The refrigerant in the compressor 111 flows into the outdoor heat exchanger 112 through the d end and the c end of the four-way valve 114, and releases heat in the water-side heat exchanger 131, and then flows out of the outdoor unit through the expansion valve 121 and flows into the indoor unit. The refrigerant flowing into the indoor unit passes through the water-side heat exchanger 131 of the indoor unit, which acts as an evaporator. The refrigerant absorbs heat at the water-side heat exchanger 131, thereby reducing the air temperature and further reducing the indoor temperature. Subsequently, the refrigerant in the indoor unit flows into the gas-liquid separator 113 through the e end and the s end of the four-way valve 114, and then flows back to the compressor 111, forming a refrigeration cycle.

[0067] In some embodiments, when the air conditioner is in the heating mode, the d end and the e end of the four-way valve 114 are connected, and the c end and the s end are connected. At this time, the outdoor heat exchanger 112 acts as an evaporator, and the water-side heat exchanger 131 acts as a condenser. The refrigerant in the compressor 111 flows into the indoor unit through the d end and the e end of the four-way valve 114, passes through the water-side heat exchanger 131, which acts as a condenser, and releases heat in the water-side heat exchanger 131. The indoor air is sucked by the indoor fan 133 and passes through the water-side heat exchanger 131. Due to the heat release of the refrigerant in the process, the air exchanges heat at the water-side heat exchanger 131, thereby increasing the indoor temperature. After the refrigerant flows out of the water-side heat exchanger 131, it enters the outdoor heat exchanger 112 and absorbs heat. Subsequently, the refrigerant flows into the gas-liquid separator 113 through the c end and the s end of the four-way valve 114, and then flows back to the compressor 111, forming a heating cycle.

[0068] Figure 6 A hardware configuration block diagram of the air conditioner provided by the present application according to an exemplary embodiment is provided. As shown in the figure, the air conditioner 10 can also include the following two items: a communicator 1002 and a memory 1003. Figure 6

[0069] In some embodiments, the communicator 1002 is configured to establish a communication connection with other network entities, such as a terminal device. The communicator 1002 can include a radio frequency (RF) module, a cellular module, a wireless fidelity (WIFI) module, and a GPS module, etc. Taking the RF module as an example, the RF module can be used for receiving and sending signals, in particular, sending the received information to the controller 1000 for processing; in addition, sending the signals generated by the controller 1000. Generally, the RF circuit can include but is not limited to an antenna, at least one amplifier, a transceiver, a coupler, a low noise amplifier (LNA), a duplexer, etc. ​

[0070] In some embodiments, the memory 1003 can be used to store software programs and data. The controller 1000 performs various functions of the air conditioner 10 and data processing by running the software programs or data stored in the memory 1003. The memory 1003 can include a high-speed random access memory, and can also include a non-volatile memory such as at least one magnetic disk storage device, a flash memory device, or other non-volatile solid-state memory device. The memory 1003 stores an operating system that enables the air conditioner 10 to operate. In the present application, the memory 1003 can store an operating system and various application programs, and can also store code for performing the control method of the air conditioner 10 provided by the embodiments of the present application.

[0071] Those skilled in the art can understand that the hardware structure shown in the above Figure 6 The hardware structure shown in the above does not constitute a limitation on the air conditioner 10, and the air conditioner 10 can include more or fewer components than shown, or combine certain components, or different component arrangements.

[0072] Figure 7 A flowchart of a control method of an air conditioner provided by the embodiments of the present application. As shown in the figure, the method includes the following steps: Figure 7

[0073] S101, the controller acquires an ambient temperature and an outdoor heat exchanger temperature.

[0074] Optionally, the controller can acquire the ambient temperature detected by the first temperature sensor and the outdoor heat exchanger temperature detected by the second temperature sensor.

[0075] S102, the controller determines a target defrosting strategy of the outdoor heat exchanger from a plurality of defrosting strategies based on the ambient temperature and the outdoor heat exchanger temperature.

[0076] Among the plurality of defrosting strategies, different defrosting strategies are used to cope with different degrees of frosting of the water-side heat exchanger, and each defrosting strategy includes a temperature condition for the air conditioner to enter a defrosting period, an interval duration between two adjacent defrosting periods, an expansion valve opening degree, and a switching time of the four-way valve after the end of the defrosting period.

[0077] In some embodiments, the plurality of defrosting strategies includes a first defrosting strategy, a second defrosting strategy, and a third defrosting strategy; wherein the degrees of frosting of the outdoor heat exchanger that the first defrosting strategy, the second defrosting strategy, and the third defrosting strategy cope with increase in turn.

[0078] Figure 8 A schematic diagram of the relationship between the target defrosting strategy provided by the embodiments of the present application and the degree of frosting of the outdoor heat exchanger that the target defrosting strategy copes with. As shown in the figure, Figure 8 ​As shown, the frosting degree of the outdoor heat exchanger corresponding to the third defrosting strategy is greater than the frosting degree of the outdoor heat exchanger corresponding to the second defrosting strategy, and the frosting degree of the outdoor heat exchanger corresponding to the second defrosting strategy is greater than the frosting degree of the outdoor heat exchanger corresponding to the first defrosting strategy.

[0079] In some embodiments, when the environment temperature is not within the preset environment temperature range, the target defrosting strategy is determined to be the first defrosting strategy.

[0080] It should be noted that the preset environment temperature range is set by the air conditioner manufacturer and pre-stored in the memory, and the preset environment temperature range of different manufacturers can vary, which is not limited in the present application.

[0081] In a specific implementation, the preset environment temperature is represented by [-m, m].

[0082] For example, when the environment temperature T a is not within the range of [-m, m], that is, when T a >m or T a <-m, the target defrosting strategy is determined to be the first defrosting strategy.

[0083] In some embodiments, when the target defrosting strategy of the air conditioner is the first defrosting strategy, at this time, the frosting degree of the outdoor heat exchanger is light frosting, and the temperature condition for the air conditioner to enter the defrosting cycle satisfies T e <a*T a +b, the interval time between two adjacent defrosting cycles is the first time, the opening degree of the expansion valve is the first opening degree, and the switching time of the four-way valve after the end of the defrosting cycle is the time after the first time interval after the end of the defrosting cycle.

[0084] Wherein, T e is the outdoor heat exchanger temperature, T a is the environment temperature, and a and b are constants.

[0085] It should be noted that a, b, the first time t1, the first opening degree n1%, and the first time interval ti1 are set by the air conditioner manufacturer and pre-stored in the memory, and the values of a, b, t1, n1%, and ti1 of different manufacturers can vary, which is not limited in the present application.

[0086] For example, if the target defrosting strategy of the air conditioner is the first defrosting strategy, when the environment temperature T a and the outdoor heat exchanger temperature T e satisfy T e <a*T aWhen the relationship of T+b is satisfied, the air conditioner enters a defrosting period. At this time, the interval time between two adjacent defrosting periods is t1 (for example, 50 minutes), the opening degree of the expansion valve is n1% (for example, 80%), and the four-way valve switches direction after ti1 seconds (for example, 20 seconds) at the end of the defrosting period of the air conditioner.

[0087] In some embodiments, when the ambient temperature is within a preset ambient temperature range, and the outdoor heat exchanger temperature and the ambient temperature satisfy the relationship of a*T a +b e >a*T a +b-c, the target defrosting strategy is determined as the second defrosting strategy.

[0088] Wherein, a, b and c are set by the manufacturer of the air conditioner and are pre-stored in the memory. The values of a, b and c of different manufacturers can vary, which is not limited in the present application.

[0089] Optionally, c can be 5.

[0090] For example, when the ambient temperature T a is within the range of [-m, m], that is, -m≤T a ≤m, if the length of the current defrosting period is within a preset fixed length, and the relationship of a*T a +b e >a*T a +b-5 is satisfied, the target defrosting strategy is determined as the second defrosting strategy.

[0091] In some embodiments, when the target defrosting strategy of the air conditioner is the second defrosting strategy, the frosting degree of the outdoor heat exchanger is moderate frosting, and the temperature condition for the air conditioner to enter the defrosting period satisfies T e <a*T a +b, the interval time between two adjacent defrosting periods is a second length, the opening degree of the expansion valve is a second opening degree, and the switching time of the four-way valve after the defrosting period is a second time interval after the end of the defrosting period.

[0092] Wherein, the second length is less than the first length, the second opening degree is less than the first opening degree, and the second time interval is less than the first time interval.

[0093] Optionally, the relationship between the second length and the first length t1 is shown in formula (1):

[0094] t2=t1*c (0.8

[0095] Optionally, the relationship between the second opening degree n1% and the second opening degree n2% is shown in formula (2):

[0096] n2% = n1% * d (0.8 < d < 1) Equation (2)

[0097] Optionally, the relationship between the second time interval ti2 and the first time interval ti1 is shown in Equation (3):

[0098] ti2 = ti1 * e (0.8 < e < 1) Equation (3)

[0099] wherein c, d and e are constants, which are pre-stored in the memory by the air conditioner manufacturer, and the values of c, d and e of different manufacturers can vary, which is not limited by the present application.

[0100] For example, if the target defrosting strategy of the air conditioner is the second defrosting strategy, when the ambient temperature T a and the outdoor heat exchanger temperature T e satisfy the relationship T e < a * T a + b, the air conditioner enters the defrosting period. At this time, the interval time between the adjacent two defrosting periods is t2 (for example, 50 * 0.9 = 45 minutes), the opening degree of the expansion valve is n2% (for example, 80% * 0.9 = 72%), and the four-way valve switches direction after ti1 seconds (for example, 20 * 0.9 = 18 seconds) of the end of the defrosting period of the air conditioner.

[0101] In some embodiments, when the ambient temperature is within a preset ambient temperature range, and the outdoor heat exchanger temperature and the ambient temperature satisfy the relationship T e ≤ a * T a + b - c, it is determined that the target defrosting strategy is the third defrosting strategy.

[0102] For example, when the ambient temperature T a is within the range of [-m, m], that is, when -m ≤ T a ≤ m, if the length of the current defrosting period is within a preset fixed length, and T e ≤ a * T a + b - 5, it is determined that the target defrosting strategy is the third defrosting strategy.

[0103] In some embodiments, when the target defrosting strategy of the air conditioner is the third defrosting strategy, at this time, the frosting degree of the outdoor heat exchanger is heavy frosting, the temperature condition for the air conditioner to enter the defrosting period satisfies T e < a * T a + b - c, the interval time between the adjacent two defrosting periods is the third length, the opening degree of the expansion valve is the third opening degree, and the switching time of the four-way valve after the end of the defrosting period is the time after the third time interval after the end of the defrosting period.

[0104] The third time length is less than the second time length, the third opening degree is less than the second opening degree, and the third time interval is less than the second time interval.

[0105] Optionally, a relationship between the third time length and the first time length t1 is shown in formula (4):

[0106] t3 = t1 * f (0 < f < 0.8) formula (4)

[0107] Optionally, a relationship between the third opening degree n3% and the second opening degree n2% is shown in formula (5):

[0108] n3% = n1% * g (0 < g < 0.8) formula (5)

[0109] Optionally, a relationship between the third time interval ti2 and the first time interval ti1 is shown in formula (6):

[0110] ti3 = ti1 * h (0 < h < 0.8) formula (6)

[0111] The f, g, and h are constants, which are pre-stored in the memory by the air conditioner manufacturer, and the values of f, g, and h of different manufacturers can be changed, which are not limited in the present application.

[0112] For example, if the target defrosting strategy of the air conditioner is the third defrosting strategy, when the environment temperature T a and the outdoor heat exchanger temperature T e satisfy the relationship T e < a * T a + b - 5, the air conditioner enters the defrosting period. At this time, the interval time length between two adjacent defrosting periods is t3 (for example, 50 * 0.5 = 25 minutes), the opening degree of the expansion valve is n3% (for example, 80% * 0.5 = 40%), and the four-way valve switches direction after the end of the defrosting period of the air conditioner ti3 seconds (for example, 20 * 0.5 = 10 seconds).

[0113] It is to be noted that when the air conditioner enters the defrosting period, the time length of each defrosting period is a pre-set fixed time length. The fixed time length can be 30 minutes, 40 minutes, or other possible time lengths, which are not limited in the present application.

[0114] S103, the controller controls the air conditioner to execute the target defrosting strategy.

[0115] Figure 9 Another flow chart of the control method of the air conditioner provided by the embodiment of the present application is shown in FIG. 3. Figure 9

[0116] For example, if the target defrosting strategy of the air conditioner is the first defrosting strategy, when the environment temperature T a ​satisfies T e satisfies T e a*T a +b, the air conditioner can enter the defrosting cycle. Meanwhile, the interval time between the adjacent two defrosting cycles is adjusted to t1, the expansion valve opening degree is adjusted to n1%, and the direction of the four-way valve is switched ti1 seconds after the end of the defrosting cycle of the air conditioner.

[0117] For example, if the target defrosting strategy of the air conditioner is the second defrosting strategy, when the ambient temperature and the outdoor heat exchanger temperature T a satisfies T e satisfies T e a*T a +b-5, the air conditioner can enter the defrosting cycle. Meanwhile, the interval time between the adjacent two defrosting cycles is adjusted to t3, the expansion valve opening degree is adjusted to n3%, and the direction of the four-way valve is switched ti3 seconds after the end of the defrosting cycle of the air conditioner.

[0118] For example, if the target defrosting strategy of the air conditioner is the third defrosting strategy, when the ambient temperature and the outdoor heat exchanger temperature T a satisfies T e satisfies T e a*T a +b-5, the air conditioner can enter the defrosting cycle. Meanwhile, the interval time between the adjacent two defrosting cycles is adjusted to t3, the expansion valve opening degree is adjusted to n3%, and the direction of the four-way valve is switched ti3 seconds after the end of the defrosting cycle of the air conditioner.

[0119] In some embodiments, if the air conditioner does not satisfy the temperature condition for entering the defrosting cycle after determining the target defrosting strategy, the air conditioner continues to run and does not enter the defrosting cycle.

[0120] The technical scheme provided by the embodiments of the present application at least brings the following beneficial effects: the scheme sets multiple defrosting strategies for coping with different frosting degrees of the outdoor heat exchanger. The ambient temperature and the outdoor heat exchanger temperature are used to determine the target defrosting strategy currently applicable to the outdoor heat exchanger from the multiple defrosting strategies. The different target defrosting strategies are adopted by the outdoor heat exchanger under different frosting degrees, and the operating parameters of the air conditioner are adjusted based on the different target defrosting strategies, so as to ensure the stable operation of the compressor in the defrosting cycle and after the defrosting cycle, and avoid problems such as compressor oil shortage, false defrosting, and incomplete defrosting caused by a large amount of flash evaporation of refrigerant when the four-way valve is switched, thereby realizing targeted, reasonable, and reliable defrosting of the air conditioner.

[0121] The embodiments of the present application also provide a hardware structure schematic diagram of a controller, as shown in Figure 10As shown, the controller 1000 includes a processor 1001, and optionally, the controller 1000 further includes a memory 1003 and a communicator 1002 connected to the processor 1001. The processor 1001, the memory 1003 and the communicator 1002 are connected through a bus 1004.

[0122] The processor 1001 can be a central processing unit (CPU), a general-purpose processor, a network processor (NP), a digital signal processor (DSP), a microprocessor, a microcontroller, a programmable logic device (PLD), or any combination thereof. The processor 1001 can also be other devices with processing capability, such as a circuit, a device, or a software module. The processor 1001 can also include multiple CPUs, and the processor 1001 can be a single-CPU processor or a multi-CPU processor. The processor herein can refer to one or more devices, circuits, or processing cores for processing data (e.g., computer program instructions).

[0123] The memory 1003 can be a read-only memory (ROM) or other type of static storage device that can store static information and instructions, a random access memory (RAM) or other type of dynamic storage device that can store information and instructions, an electrically erasable programmable read-only memory (EEPROM), a compact disc read-only memory (CD-ROM) or other optical disk storage, a magnetic disk storage or other magnetic storage devices, or any other medium capable of carrying or storing desired program code in the form of instructions or data structures and that can be accessed by a computer, without limitation. The memory 1003 can exist independently or be integrated with the processor 1001. The memory 1003 can include computer program code. The processor 1001 is configured to execute the computer program code stored in the memory 1003, thereby implementing the control method provided by the embodiments of the present application.

[0124] The communicator 1002 can be used to communicate with other devices or communication networks (e.g., Ethernet, radio access network (RAN), wireless local area networks (WLAN), etc.). The communicator 1002 can be a module, a circuit, a transceiver, or any device capable of enabling communication.

[0125] The bus 1004 can be a peripheral component interconnect (PCI) bus or an extended industry standard architecture (EISA) bus, etc. The bus 1004 can be divided into an address bus, a data bus, a control bus, etc. For ease of representation, Figure 10 Only one thick line is used to represent the bus in the middle, but it does not mean that there is only one bus or only one type of bus.

[0126] The embodiment of the present application further provides a computer readable storage medium, which comprises computer execution instructions, and when the computer execution instructions run on a computer, the computer execution instructions make the computer execute the method provided by the above embodiment.

[0127] The embodiment of the present application further provides a computer program product, which can be directly loaded into a memory and contains software codes, and the computer program product can realize the method provided by the above embodiment after being loaded and executed by a computer.

[0128] Those skilled in the art can realize that the functions described in the above one or more examples can be realized by hardware, software, firmware or any combination thereof. When realized by software, the functions can be stored in a computer readable medium or transmitted as one or more instructions or codes on a computer readable medium. The computer readable medium includes a computer storage medium and a communication medium, wherein the communication medium includes any medium that facilitates the transmission of computer programs from one place to another. The storage medium can be any available medium that can be accessed by a general or special purpose computer.

[0129] Through the above description of the embodiments, those skilled in the art can clearly understand that, for the convenience and brevity of description, only the division of the above functional modules is taken as an example for illustration, and in actual application, the above functions can be completed by different functional modules according to needs, that is, the internal structure of the device is divided into different functional modules to complete all or part of the functions described above.

[0130] In several embodiments provided in the present application, it should be understood that the disclosed apparatus and method can be implemented in other manners. For example, the division of the apparatus embodiments is only illustrative and each division can not necessarily exist in actual implementation. For example, a plurality of units or components can be combined or integrated into another system, or some features can be ignored or not executed. In addition, the displayed or discussed mutual couplings or direct couplings or communication connections can be indirect couplings or communication connections through some interfaces, devices or units, and can be in electrical, mechanical or other forms.

[0131] In addition, each function unit in the various embodiments of the present application can be integrated into a processing unit, or each unit can exist physically separately, or two or more units can be integrated into one unit. The integrated unit can be implemented in the form of hardware or in the form of a software function unit. When the integrated unit is implemented in the form of a software function unit and sold or used as an independent product, it can be stored in a readable storage medium. Based on such an understanding, the technical solutions of the embodiments of the present application essentially or substantially, or all or part of the technical solutions, can be embodied in the form of a software product. The software product is stored in a storage medium, and includes several instructions for causing an apparatus (which can be a single chip, a chip, etc.) or a processor to perform all or part of the steps of the methods in the various embodiments of the present application. The foregoing storage medium includes: U disk, mobile hard disk, ROM, RAM, magnetic disk or optical disk, and various other media that can store program codes.

[0132] The above is only a specific implementation of the present application, but the protection scope of the present application is not limited thereto. Any change or replacement within the technical scope disclosed in the present application should be covered in the protection scope of the present application. Therefore, the protection scope of the present application should be subject to the protection scope of the claims.

Claims

1. An air conditioner, characterized in that, include: The refrigerant circulation loop allows the refrigerant to circulate in a loop consisting of the compressor, outdoor heat exchanger, water-side heat exchanger, expansion valve, and four-way valve. The outdoor heat exchanger is a finned heat exchanger; Of the outdoor heat exchanger and the water-side heat exchanger, one functions as a condenser and the other as an evaporator. The first temperature sensor is used to detect the ambient temperature; The second temperature sensor is installed on the outdoor heat exchanger and is used to detect the temperature of the outdoor heat exchanger. The controller is configured as follows: The ambient temperature detected by the first temperature sensor and the outdoor heat exchanger temperature detected by the second temperature sensor are obtained. Based on the ambient temperature and the outdoor heat exchanger temperature, a target defrosting strategy for the outdoor heat exchanger is determined from multiple defrosting strategies. Among these multiple defrosting strategies, different strategies are used to address different degrees of frost buildup on the outdoor heat exchanger. Each defrosting strategy includes the temperature conditions for the air conditioner to enter a defrosting cycle, the interval between two adjacent defrosting cycles, the opening degree of the expansion valve, and the switching time of the four-way valve after the end of the defrosting cycle. The multiple defrosting strategies include a first defrosting strategy, a second defrosting strategy, and a third defrosting strategy. The degree of frost buildup on the outdoor heat exchanger addressed by the first defrosting strategy, the second defrosting strategy, and the third defrosting strategy increases sequentially. For the first defrosting strategy, the temperature conditions for the air conditioner to enter the defrosting cycle are satisfied. <a* +b, the interval between two adjacent defrosting cycles is a first duration, the opening degree of the expansion valve is a first opening degree, and the switching time of the four-way valve after the end of the defrosting cycle is the time after the first time interval has elapsed after the end of the defrosting cycle; wherein, The outdoor heat exchanger temperature, The ambient temperature is given, and a, b, and c are constants. For the second defrosting strategy, the temperature conditions for the air conditioner to enter the defrosting cycle are satisfied. <a* +b, the interval between two adjacent defrosting cycles is the second duration, the opening degree of the expansion valve is the second opening degree, and the switching time of the four-way valve after the end of the defrosting cycle is the time after the end of the defrosting cycle, after the second time interval; wherein, the second duration is less than the first duration, the second opening degree is less than the first opening degree, and the second time interval is less than the first time interval. Control the air conditioner to execute the target defrosting strategy.

2. The air conditioner according to claim 1, characterized in that, The controller is specifically configured as follows: When the ambient temperature is not within the preset ambient temperature range, the target defrosting strategy is determined to be the first defrosting strategy.

3. The air conditioner according to claim 2, characterized in that, The controller is specifically configured as follows: When the ambient temperature is within the preset ambient temperature range, and the outdoor heat exchanger temperature satisfies a* +b> >a* When +bc is reached, the target defrosting strategy is determined to be the second defrosting strategy.

4. The air conditioner according to claim 3, characterized in that, The controller is specifically configured as follows: When the ambient temperature is within the preset ambient temperature range, and the outdoor heat exchanger temperature satisfies the condition of the ambient temperature... ≤a* When +bc is reached, the target defrosting strategy is determined to be the third defrosting strategy.

5. The air conditioner according to claim 4, characterized in that, For the third defrosting strategy, the temperature conditions for the air conditioner to enter the defrosting cycle are satisfied. <a* +bc, the interval between two adjacent defrosting cycles is the third duration, the opening degree of the expansion valve is the third opening degree, and the switching time of the four-way valve after the end of the defrosting cycle is the time after the end of the defrosting cycle, after the third time interval; the third duration is less than the second duration, the third opening degree is less than the second opening degree, and the third time interval is less than the second time interval.

6. A control method for an air conditioner, characterized in that, The method includes: Obtain the ambient temperature and the outdoor heat exchanger temperature; Based on the ambient temperature and the outdoor heat exchanger temperature, a target defrosting strategy for the outdoor heat exchanger is determined from multiple defrosting strategies. Different defrosting strategies among the multiple defrosting strategies are used to deal with different degrees of frost on the outdoor heat exchanger. The air conditioner is controlled to operate with the defrosting parameters in the target defrosting strategy, the defrosting parameters including the target operating parameters of the air conditioner; the target operating parameters include: the temperature conditions for the air conditioner to enter the defrosting cycle, the interval between two adjacent defrosting cycles, the opening degree of the expansion valve, and the switching time of the four-way valve after the end of the defrosting cycle; The multiple defrosting strategies include a first defrosting strategy, a second defrosting strategy, and a third defrosting strategy; wherein the degree of frost on the outdoor heat exchanger addressed by the first defrosting strategy, the second defrosting strategy, and the third defrosting strategy increases sequentially. For the first defrosting strategy, the temperature conditions for the air conditioner to enter the defrosting cycle are satisfied. <a* +b, the interval between two adjacent defrosting cycles is a first duration, the opening degree of the expansion valve is a first opening degree, and the switching time of the four-way valve after the end of the defrosting cycle is the time after the first time interval has elapsed after the end of the defrosting cycle; wherein, The outdoor heat exchanger temperature, The ambient temperature is given, and a, b, and c are constants. For the second defrosting strategy, the temperature conditions for the air conditioner to enter the defrosting cycle are satisfied. <a* +b, the interval between two adjacent defrosting cycles is the second duration, the opening degree of the expansion valve is the second opening degree, and the switching time of the four-way valve after the end of the defrosting cycle is the time after the end of the defrosting cycle, after the second time interval; wherein, the second duration is less than the first duration, the second opening degree is less than the first opening degree, and the second time interval is less than the first time interval.

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