Method, device and air conditioner for controlling air conditioner, and storage medium

Abstract

The present application relates to the technical field of air conditioning, and discloses a method for controlling an air conditioner, comprising: determining the pipe wall thickness of each heat exchanger under the condition of satisfying a preset oil return condition; determining the oil return mode of the air conditioner according to the pipe wall thickness of each heat exchanger; and controlling the air conditioner to execute the oil return mode. The present application first determines the pipe wall thickness of each heat exchanger to determine the main accumulation position of the lubricating oil in the refrigerant circulation loop. Then, based on different judgment results, the present application adaptively selects the most suitable oil return mode and executes it, thereby ensuring that the lubricating oil located at different accumulation positions can be stably recovered to increase the amount of lubricating oil recovered, which is beneficial to optimizing the oil return performance. And corresponding to different operating conditions of the air conditioner, the present application can achieve a good oil return effect, so it is beneficial to improve the reliability of the oil return program. The present application also discloses a device for controlling an air conditioner, an air conditioner, and a storage medium.

Description

Technical Field

[0001] The present application relates to the technical field of air conditioning, for example, to a method and device for controlling an air conditioner, an air conditioner, and a storage medium. Background Art

[0002] At present, the compressor needs lubricating oil for continuous lubrication during operation. However, since the lubricating oil can be miscible with the refrigerant, it is inevitable that some of the lubricating oil will leave the compressor and enter the refrigerant circulation loop along with the refrigerant circulation. In addition, the refrigerant will undergo a phase change in the heat exchanger, causing the lubricating oil carried in the refrigerant to precipitate and then remain in each heat exchanger. When too much lubricating oil is retained in the heat exchanger, the compressor will be short of oil, thereby affecting the performance of the compressor. Long-term lack of oil will also cause serious wear or failure of the compressor. Therefore, it is necessary to perform an oil return procedure on the compressor regularly. To this end, the relevant technology proposes a method for oil return control for an air conditioner, comprising: obtaining the operating mode of the air conditioner; obtaining the operating time of the air conditioner; obtaining the coil temperature of the indoor unit of the air conditioner; and selectively causing the air conditioner to enter the oil return mode according to the operating mode of the air conditioner, the operating time of the air conditioner and the coil temperature of the indoor unit.

[0003] In the process of implementing the embodiments of the present disclosure, it is found that there are at least the following problems in the related art:

[0004] However, the related technology only recovers the lubricating oil inside the indoor unit, and the amount of lubricating oil recovered is limited. Especially in winter, when air conditioners are mostly operated in heating mode, the lubricating oil entering the refrigerant circulation loop is more likely to remain in the heat exchanger of the outdoor unit. At this time, the oil return effect of the related technology is poor, and the reliability of the oil return program is low.

[0005] It should be noted that the information disclosed in the above background technology section is only used to enhance the understanding of the background of the present application, and therefore may include information that does not constitute the prior art known to ordinary technicians in the field. Summary of the invention

[0006] In order to provide a basic understanding of some aspects of the disclosed embodiments, a brief summary is given below. The summary is not an extensive review, nor is it intended to identify key / critical components or delineate the scope of protection of these embodiments, but rather serves as a prelude to the detailed description that follows.

[0007] The embodiments of the present disclosure provide a method and device for controlling an air conditioner, an air conditioner, and a storage medium, which can optimize the oil return performance and help improve the reliability of the oil return program.

[0008] In some embodiments, the method includes: determining the pipe wall thickness of each heat exchanger when a preset oil return condition is met; determining the oil return mode of the air conditioner based on the pipe wall thickness of each heat exchanger; and controlling the air conditioner to execute the oil return mode.

[0009] In some embodiments, the device includes: a processor and a memory storing program instructions, and the processor is configured to execute the above-mentioned method for controlling an air conditioner when running the program instructions.

[0010] In some embodiments, the air conditioner includes: a refrigerant circulation loop, which is composed of a compressor, a four-way valve, an indoor heat exchanger, a throttle valve and an outdoor heat exchanger connected by a refrigerant pipeline; an indoor fan, which is arranged corresponding to the indoor heat exchanger; an outdoor fan, which is arranged corresponding to the outdoor heat exchanger; a heating device, which is arranged in the compressor to heat the liquid refrigerant in the compressor; and the above-mentioned device for controlling the air conditioner.

[0011] In some embodiments, the storage medium stores program instructions, and when the program instructions are run, the above-mentioned method for controlling the air conditioner is executed.

[0012] The method, device, air conditioner, and storage medium for controlling an air conditioner provided in the embodiments of the present disclosure can achieve the following technical effects:

[0013] In the embodiment of the present disclosure, the relevant parameters inside the air conditioner are detected to determine whether the preset oil return conditions are met. If the preset oil return conditions are met, it is determined that the current time is appropriate, and the embodiment of the present disclosure starts to execute the oil return program. Since the air conditioner is in different operating conditions, there are certain differences in the retention points of the lubricating oil. Therefore, the embodiment of the present disclosure first determines the pipe wall thickness of each heat exchanger to determine the main accumulation position of the lubricating oil in the refrigerant circulation loop. Then, based on different judgment results, the embodiment of the present disclosure adaptively selects the most suitable oil return mode and executes it, so as to ensure that the lubricating oil located at different accumulation positions can be stably recovered, so as to increase the recovery amount of the lubricating oil, which is beneficial to optimize the oil return performance. And corresponding to the different operating conditions of the air conditioner, the embodiments of the present disclosure can achieve a better oil return effect, so it is beneficial to improve the reliability of the oil return program.

[0014] The above general description and the following description are exemplary and explanatory only and are not intended to limit the present application. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] One or more embodiments are exemplarily described by corresponding drawings, which do not limit the embodiments. Elements with the same reference numerals in the drawings are shown as similar elements, and the drawings do not constitute a scale limitation, and wherein:

[0016] Figure 1 is a structural schematic diagram of an air conditioner provided by an embodiment of the present disclosure;

[0017] Figure 2 is a schematic diagram of a method for controlling an air conditioner provided by an embodiment of the present disclosure;

[0018] Figure 3 is a schematic diagram of another method for controlling an air conditioner provided by an embodiment of the present disclosure;

[0019] Figure 4 is a schematic diagram of another method for controlling an air conditioner provided by an embodiment of the present disclosure;

[0020] Figure 5 is a schematic diagram of another method for controlling an air conditioner provided by an embodiment of the present disclosure;

[0021] Figure 6 is a schematic diagram of another method for controlling an air conditioner provided by an embodiment of the present disclosure;

[0022] Figure 7 is a schematic diagram of another method for controlling an air conditioner provided by an embodiment of the present disclosure;

[0023] Figure 8 is a schematic diagram of a device for controlling an air conditioner provided in an embodiment of the present disclosure.

[0024] Reference numerals:

[0025] 10: compressor; 20: four-way valve; 30: indoor heat exchanger; 40: outdoor heat exchanger; 50: throttle valve; 60: indoor fan; 70: outdoor fan; 80: heating device. DETAILED DESCRIPTION

[0026] In order to be able to understand the features and technical contents of the embodiments of the present disclosure in more detail, the implementation of the embodiments of the present disclosure is described in detail below in conjunction with the accompanying drawings. The attached drawings are for reference only and are not used to limit the embodiments of the present disclosure. In the following technical description, for the convenience of explanation, a full understanding of the disclosed embodiments is provided through multiple details. However, one or more embodiments can still be implemented without these details. In other cases, to simplify the drawings, well-known structures and devices can be simplified for display.

[0027] The terms "first", "second", etc. in the specification and claims of the embodiments of the present disclosure and the above-mentioned drawings are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence. It should be understood that the terms used in this way can be interchanged where appropriate, so that the embodiments of the embodiments of the present disclosure described herein. In addition, the terms "including" and "having" and any variations thereof are intended to cover non-exclusive inclusions.

[0028] Unless otherwise stated, the term "plurality" means two or more.

[0029] In the embodiment of the present disclosure, the character " / " indicates that the preceding and following objects are in an "or" relationship. For example, A / B indicates: A or B.

[0030] The term "and / or" is a description of the association relationship between objects, indicating that three relationships can exist. For example, A and / or B means: A or B, or, A and B.

[0031] The term "correspondence" may refer to an association relationship or a binding relationship. The correspondence between A and B means that there is an association relationship or a binding relationship between A and B.

[0032] At present, the compressor needs lubricating oil for continuous lubrication during operation. However, since the lubricating oil can be miscible with the refrigerant, it is inevitable that some of the lubricating oil will leave the compressor and enter the refrigerant circulation loop along with the refrigerant circulation. In addition, the refrigerant will undergo a phase change in the heat exchanger, causing the lubricating oil carried in the refrigerant to precipitate and then remain in each heat exchanger. When too much lubricating oil is retained in the heat exchanger, the compressor will be short of oil, thereby affecting the performance of the compressor. Long-term lack of oil will also cause serious wear or failure of the compressor. Therefore, it is necessary to perform an oil return procedure on the compressor regularly. To this end, the relevant technology proposes a method for oil return control for an air conditioner, comprising: obtaining the operating mode of the air conditioner; obtaining the operating time of the air conditioner; obtaining the coil temperature of the indoor unit of the air conditioner; and selectively causing the air conditioner to enter the oil return mode according to the operating mode of the air conditioner, the operating time of the air conditioner and the coil temperature of the indoor unit.

[0033] However, the related technology uses the air conditioner operation time and the indoor unit coil temperature as the judgment points, and relies more on experience judgment. It cannot clearly know the specific oil situation inside the air conditioner, so the perception of oil shortage is not accurate enough. In addition, the related technology only recovers the lubricating oil inside the indoor unit, and the amount of lubricating oil recovered is limited. Especially in winter, air conditioners are mostly operated in heating mode, and the lubricating oil entering the refrigerant circulation loop is more retained in the heat exchanger of the outdoor unit. At this time, the oil return effect of the related technology is poor, and the reliability of the oil return program is low.

[0034] Combination Figure 1As shown, the embodiment of the present disclosure provides an air conditioner, including a refrigerant circulation circuit, which is composed of a compressor 10, a four-way valve 20, an indoor heat exchanger 30, a throttle valve 50 and an outdoor heat exchanger 40 connected by a refrigerant pipeline. An indoor fan 60 is provided corresponding to the indoor heat exchanger 30. An outdoor fan 70 is provided corresponding to the outdoor heat exchanger 40. A heating device 80 is provided in the compressor 10 to heat the liquid refrigerant in the compressor 10.

[0035] The air conditioner provided by the embodiment of the present disclosure is provided with a heating device 80 in the compressor 10, which can heat the liquid refrigerant returning to the compressor 10 to convert the liquid refrigerant in the compressor 10 into a gaseous refrigerant, thereby allowing the lubricating oil carried by the refrigerant to precipitate, thereby completing the oil return operation of the compressor 10.

[0036] Optionally, the heating device 80 is a heating rod. It is understandable that the form of the heating device 80 is not unique, and the heating device 80 can also be a heater, an electromagnetic heating device, or other elements with heating functions. In this way, the embodiment of the present disclosure can use the heating device 80 to heat the liquid refrigerant returning to the compressor 10 to convert the liquid refrigerant in the compressor 10 into a gaseous refrigerant, so that the lubricating oil carried by the refrigerant can be precipitated, completing the oil return operation of the compressor 10.

[0037] Optionally, a filter bottle is provided in the compressor 10, and the filter bottle is provided with a liquid inlet and an oil outlet. The liquid inlet is configured to allow the liquid refrigerant in the refrigerant circulation loop to enter the filter bottle. The oil outlet is configured to allow the lubricating oil in the filter bottle to be discharged to the oil pool inside the compressor 10. The heating device 80 is provided in the filter bottle, and is configured to heat the liquid refrigerant in the filter bottle to convert the liquid refrigerant in the filter bottle into a gaseous refrigerant, so that the lubricating oil carried by the refrigerant can be precipitated, which is conducive to ensuring that the lubricating oil is stably recovered and improving the reliability of oil return.

[0038] Based on the above air conditioner structure, combined with Figure 2 As shown, the embodiment of the present disclosure provides a method for controlling an air conditioner, comprising:

[0039] S201, when a preset oil return condition is met, the processor determines the pipe wall thickness of each heat exchanger.

[0040] S202: The processor determines the oil return mode of the air conditioner according to the pipe wall thickness of each heat exchanger.

[0041] S203, the processor controls the air conditioner to execute the oil return mode.

[0042] The method for controlling an air conditioner provided by the embodiment of the present disclosure is adopted to determine whether the preset oil return condition is met by detecting relevant parameters inside the air conditioner. If the preset oil return condition is met, it is determined that the current time is appropriate, and the embodiment of the present disclosure starts to execute the oil return program. Since the air conditioner is in different operating conditions, there are certain differences in the retention points of the lubricating oil. Therefore, the embodiment of the present disclosure first determines the pipe wall thickness of each heat exchanger to determine the main accumulation position of the lubricating oil in the refrigerant circulation loop. Then, based on different judgment results, the embodiment of the present disclosure adaptively selects the most suitable oil return mode and executes it, so as to ensure that the lubricating oil located at different accumulation positions can be stably recovered to increase the recovery amount of the lubricating oil, which is beneficial to optimize the oil return performance. And corresponding to the different operating conditions of the air conditioner, the embodiments of the present disclosure can achieve a better oil return effect, so it is beneficial to improve the reliability of the oil return program.

[0043] Optionally, the preset oil return condition includes: the lubricating oil level of the compressor is less than or equal to the preset level. In this way, when the lubricating oil level is lower than the preset level, it indicates that the current lubricating oil content in the compressor is insufficient to effectively lubricate the compressor, and the oil return program needs to be started immediately. By detecting the lubricating oil level in the oil pool inside the compressor, the embodiment of the present disclosure can intuitively know whether the compressor is currently short of oil. This is conducive to more accurately determining the timing of starting the oil return program and performing the oil return operation on the compressor in a timely manner.

[0044] Optionally, the preset oil return condition includes: the pipe wall thickness of the indoor heat exchanger is greater than or equal to a first preset thickness. In this way, when the pipe wall thickness of the indoor heat exchanger exceeds the first preset thickness, it indicates that too much lubricating oil has left the compressor and is retained near the indoor heat exchanger. At this time, the lubricating oil content inside the compressor is not enough to effectively lubricate the compressor, and the oil return program needs to be started immediately. By detecting the pipe wall thickness of the indoor heat exchanger, the embodiment of the present disclosure can indirectly determine whether the compressor is currently short of oil, which is helpful to assist in determining the timing of starting the oil return program and timely perform the oil return operation on the compressor.

[0045] Optionally, the preset oil return condition includes: the pipe wall thickness of the outdoor heat exchanger is greater than or equal to a second preset thickness. In this way, when the pipe wall thickness of the outdoor heat exchanger exceeds the second preset thickness, it indicates that too much lubricating oil has left the compressor and is retained near the outdoor heat exchanger. At this time, the lubricating oil content inside the compressor is not enough to effectively lubricate the compressor, and the oil return program needs to be started immediately. By detecting the pipe wall thickness of the outdoor heat exchanger, the embodiment of the present disclosure can indirectly determine whether the compressor is currently short of oil, which is helpful to assist in determining the timing of starting the oil return program and timely perform the oil return operation on the compressor.

[0046] Optionally, the preset oil return condition includes: the sum of the pipe wall thickness of the indoor heat exchanger and the pipe wall thickness of the outdoor heat exchanger is greater than or equal to a third preset thickness. In this way, when the sum of the pipe wall thickness of the indoor heat exchanger and the outdoor heat exchanger exceeds the third preset thickness, it indicates that too much lubricating oil has left the compressor and is retained near each heat exchanger. At this time, the lubricating oil content inside the compressor is not enough to effectively lubricate the compressor, and the oil return program needs to be started immediately. By detecting the pipe wall thickness of the indoor heat exchanger and the outdoor heat exchanger, the embodiment of the present disclosure can indirectly determine whether the compressor is currently short of oil, which is helpful to assist in determining the timing of starting the oil return program and timely perform the oil return operation on the compressor.

[0047] Optionally, the disclosed embodiment may also set other preset oil return conditions, which are not limited to the above-mentioned judgment conditions. The preset oil return conditions may be set according to the specific operating conditions of the air conditioner to cope with more complex lubricating oil accumulation conditions, which are not listed here one by one. At the same time, the preset oil return conditions may also be organically combined on the basis of the above-mentioned multiple judgment conditions to further improve the accuracy of determining the start time of the oil return program.

[0048] Optionally, the processor determines the pipe wall thickness of each heat exchanger, including: the processor controls the first ultrasonic thickness sensor to detect the thickness of the outlet pipe of the indoor heat exchanger for cooling flow to obtain the pipe wall thickness of the indoor heat exchanger; the processor controls the second ultrasonic thickness sensor to detect the thickness of the outlet pipe of the outdoor heat exchanger for heating flow to obtain the pipe wall thickness of the outdoor heat exchanger. In this way, by installing ultrasonic thickness sensors at the outlet pipes of each heat exchanger, the embodiment of the present disclosure can accurately obtain the pipe wall thickness of the indoor heat exchanger and the pipe wall thickness of the outdoor heat exchanger, so as to facilitate the determination of the main accumulation position of the lubricating oil in the refrigerant circulation loop.

[0049] Optionally, the processor determines the oil return mode of the air conditioner according to the pipe wall thickness of each heat exchanger, including: when the pipe wall thickness of the indoor heat exchanger is greater than or equal to the pipe wall thickness of the outdoor heat exchanger, the processor determines the oil return mode of the air conditioner to be the first oil return mode; when the pipe wall thickness of the indoor heat exchanger is less than the pipe wall thickness of the outdoor heat exchanger, the processor determines the oil return mode of the air conditioner to be the second oil return mode. In this way, since the air conditioner is in different operating conditions, there are certain differences in the retention points of the lubricating oil, so there may be multiple situations where the lubricating oil is more accumulated in the indoor heat exchanger or more accumulated in the outdoor heat exchanger. By comparing the pipe wall thickness of the indoor heat exchanger and the pipe wall thickness of the outdoor heat exchanger, the embodiment of the present disclosure can determine the main accumulation position of the lubricating oil in the refrigerant circulation loop to determine which lubricating oil accumulation situation the air conditioner is currently in. Corresponding to different accumulation situations of the lubricating oil, the embodiment of the present disclosure can provide differentiated oil return modes to ensure the oil return effect in various situations. By executing the most suitable oil return mode under the current situation, the embodiment of the present disclosure can ensure that more lubricating oil can be stably recovered, thereby increasing the amount of lubricating oil recovered, which is conducive to optimizing the oil return performance. In addition, corresponding to different operating conditions of the air conditioner, the embodiment of the present disclosure can achieve a good oil return effect, thus helping to improve the reliability of the oil return program.

[0050] Based on the above air conditioner structure, combined with Figure 3 As shown, the embodiment of the present disclosure provides another method for controlling an air conditioner, comprising:

[0051] S301, when a preset oil return condition is met, the processor determines the pipe wall thickness of each heat exchanger.

[0052] S302: When the pipe wall thickness of the indoor heat exchanger is greater than or equal to the pipe wall thickness of the outdoor heat exchanger, the processor determines that the oil return mode of the air conditioner is the first oil return mode.

[0053] S303, the processor controls the air conditioner to execute the first oil return mode.

[0054] S304: When the pipe wall thickness of the indoor heat exchanger is smaller than the pipe wall thickness of the outdoor heat exchanger, the processor determines that the oil return mode of the air conditioner is the second oil return mode.

[0055] S305: the processor controls the air conditioner to execute the second oil return mode.

[0056] The method for controlling an air conditioner provided by the embodiment of the present disclosure is adopted to determine whether the preset oil return condition is met by detecting relevant parameters inside the air conditioner. If the preset oil return condition is met, it is determined that the current time is appropriate, and the embodiment of the present disclosure starts to execute the oil return program. Since the air conditioner is in different operating conditions, there are certain differences in the retention points of the lubricating oil, so there may be multiple situations where the lubricating oil is more accumulated in the indoor heat exchanger or more accumulated in the outdoor heat exchanger. By comparing the pipe wall thickness of the indoor heat exchanger and the pipe wall thickness of the outdoor heat exchanger, the embodiment of the present disclosure can determine the main accumulation position of the lubricating oil in the refrigerant circulation loop to determine which lubricating oil accumulation situation the air conditioner is currently in. And corresponding to the different accumulation situations of the lubricating oil, the embodiment of the present disclosure can provide differentiated oil return modes to ensure the oil return effect in various situations. By executing the most suitable oil return mode in the current situation, the embodiment of the present disclosure can ensure that more lubricating oil can be stably recovered, thereby increasing the recovery amount of lubricating oil, which is conducive to optimizing the oil return performance. And corresponding to the different operating conditions of the air conditioner, the embodiment of the present disclosure can achieve a good oil return effect, so it is conducive to improving the reliability of the oil return program.

[0057] Specifically, in summer, air conditioners are mostly operated in cooling mode. Since liquid refrigerant can be miscible with lubricating oil, its ability to carry lubricating oil is stronger. A large amount of lubricating oil coming out of the compressor circulates with the liquid refrigerant to the indoor heat exchanger. At this time, the liquid refrigerant entering the indoor heat exchanger will be converted into gaseous refrigerant due to heat absorption and evaporation, resulting in a decrease in the ability of the refrigerant to carry lubricating oil. Therefore, the lubricating oil will gradually precipitate from the refrigerant and then remain in the pipeline of the indoor heat exchanger. With the gradual accumulation of lubricating oil in the pipeline, the wall thickness of the indoor heat exchanger will also increase, and will be significantly greater than the wall thickness of the outdoor heat exchanger. For this reason, by controlling the air conditioner to execute the first oil return mode, the disclosed embodiment can mainly recover the lubricating oil retained at the indoor heat exchanger to increase the amount of lubricating oil recovered, which is conducive to optimizing the oil return performance.

[0058] In winter, air conditioners are mostly operated in heating mode. Since liquid refrigerant can be miscible with lubricating oil, its ability to carry lubricating oil is stronger. A large amount of lubricating oil coming out of the compressor circulates with the liquid refrigerant to the outdoor heat exchanger. At this time, the liquid refrigerant entering the outdoor heat exchanger will be converted into gaseous refrigerant due to heat absorption and evaporation, resulting in a decrease in the ability of the refrigerant to carry lubricating oil. Therefore, the lubricating oil will gradually precipitate from the refrigerant and then be retained in the pipeline of the outdoor heat exchanger. With the gradual accumulation of lubricating oil in the pipeline, the wall thickness of the pipeline of the outdoor heat exchanger will also increase, and will be significantly greater than the wall thickness of the pipeline of the indoor heat exchanger. For this reason, by controlling the air conditioner to execute the second oil return mode, the disclosed embodiment can mainly recover the lubricating oil retained at the outdoor heat exchanger to increase the amount of lubricating oil recovered, which is conducive to optimizing the oil return performance.

[0059] Optionally, the processor controls the air conditioner to execute a first oil return mode, including: the processor controls the throttle valve to close, controls the indoor fan and compressor to start, and controls the four-way valve to switch to a heating flow working state; when the first preset reversing condition is met, the processor controls the indoor fan and compressor to stop, and controls the four-way valve to switch to a cooling flow working state; the processor controls the heating device to start heating to heat the liquid refrigerant in the compressor into a gaseous refrigerant.

[0060] In this way, when the air conditioner enters the first oil return mode, the throttle valve is first controlled to close, and the disclosed embodiment can make the indoor heat exchanger no longer transport liquid refrigerant to the outdoor heat exchanger. Then the indoor fan and compressor are controlled to start, and the four-way valve is controlled to switch to the working state of the heating flow direction. The disclosed embodiment can make the refrigerant in the outdoor heat exchanger and its connected pipelines driven by the compressor flow to the indoor heat exchanger, so that the refrigerant near the outdoor heat exchanger and the compressor can be transferred to the indoor heat exchanger. And with the normal operation of the indoor fan, the gaseous refrigerant entering the indoor heat exchanger will be converted into liquid refrigerant due to condensation heat release and stored in the indoor heat exchanger pipeline. At this time, the outdoor heat exchanger and the compressor will gradually generate negative pressure because the refrigerant is transferred away. In the indoor heat exchanger, since the liquid refrigerant can be miscible with the lubricating oil, its ability to carry the lubricating oil is stronger, and the lubricating oil originally attached to the indoor heat exchanger pipe wall is dissolved in a large amount of the stored liquid refrigerant. When it is determined that the first preset reversing condition is met, it means that the refrigerant in the refrigerant circulation loop has been basically transferred. At this time, the indoor fan and compressor are controlled to stop to avoid the subsequent vaporization of liquid refrigerant after the four-way valve is turned, resulting in the re-precipitation of lubricating oil. Then the four-way valve is controlled to switch to the working state of the refrigeration flow direction. Under the negative pressure of the outdoor heat exchanger and the compressor, the liquid refrigerant carrying a large amount of lubricating oil will flow to the filter bottle inside the compressor. By controlling the heating device to start heating, the embodiment of the present disclosure can heat the liquid refrigerant returned to the compressor to convert the liquid refrigerant in the compressor into a gaseous refrigerant. At this time, the ability of the refrigerant to carry lubricating oil decreases, and the lubricating oil will gradually precipitate from the refrigerant and return to the compressor oil pool, thereby achieving the purpose of oil return of the air conditioner. Therefore, by executing the first oil return mode, the embodiment of the present disclosure can effectively recover a large amount of lubricating oil retained at the indoor heat exchanger to complete the oil return work of the compressor.

[0061] Optionally, the processor controls the air conditioner to execute a second oil return mode, including: the processor controls the throttle valve to close, controls the outdoor fan and compressor to start, and controls the four-way valve to switch to a cooling flow working state; when the second preset reversing condition is met, the processor controls the outdoor fan and compressor to stop, and controls the four-way valve to switch to a heating flow working state; the processor controls the heating device to start heating to heat the liquid refrigerant in the compressor into a gaseous refrigerant.

[0062] In this way, when the air conditioner enters the second oil return mode, the throttle valve is first controlled to close, and the disclosed embodiment can make the outdoor heat exchanger no longer transport liquid refrigerant to the indoor heat exchanger. Then the outdoor fan and the compressor are controlled to start, and the four-way valve is controlled to switch to the working state of the cooling flow direction. The disclosed embodiment can make the refrigerant in the indoor heat exchanger and its connected pipelines driven by the compressor flow to the outdoor heat exchanger, so that the refrigerant near the indoor heat exchanger and the compressor can be transferred to the outdoor heat exchanger. And with the normal operation of the outdoor fan, the gaseous refrigerant entering the outdoor heat exchanger will be converted into liquid refrigerant due to condensation heat release and stored in the outdoor heat exchanger pipeline. At this time, the indoor heat exchanger and the compressor will gradually generate negative pressure because the refrigerant is transferred away. In the outdoor heat exchanger, since the liquid refrigerant can be miscible with the lubricating oil, its ability to carry the lubricating oil is stronger, and the lubricating oil originally attached to the outdoor heat exchanger pipe wall is dissolved in a large amount of the stored liquid refrigerant. When it is determined that the second preset reversing condition is met, it means that the refrigerant in the refrigerant circulation loop has been basically transferred. At this time, the outdoor fan and the compressor are controlled to stop to avoid the subsequent vaporization of the liquid refrigerant after the four-way valve is turned, which causes the lubricating oil to precipitate again. Then the four-way valve is controlled to switch to the working state of the heating flow direction. Under the negative pressure of the indoor heat exchanger and the compressor, the liquid refrigerant carrying a large amount of lubricating oil will flow to the filter bottle inside the compressor. By controlling the heating device to start heating, the embodiment of the present disclosure can heat the liquid refrigerant returned to the compressor to convert the liquid refrigerant in the compressor into a gaseous refrigerant. At this time, the ability of the refrigerant to carry lubricating oil decreases, and the lubricating oil will gradually precipitate from the refrigerant and return to the compressor oil pool, thereby achieving the purpose of oil return of the air conditioner. Therefore, by executing the second oil return mode, the embodiment of the present disclosure can effectively recover a large amount of lubricating oil retained at the outdoor heat exchanger to complete the oil return work of the compressor.

[0063] Based on the above air conditioner structure, combined with Figure 4 As shown, the embodiment of the present disclosure provides another method for controlling an air conditioner, comprising:

[0064] S401, when a preset oil return condition is met, the processor determines the pipe wall thickness of each heat exchanger.

[0065] S402: When the pipe wall thickness of the indoor heat exchanger is greater than or equal to the pipe wall thickness of the outdoor heat exchanger, the processor determines that the oil return mode of the air conditioner is the first oil return mode.

[0066] S403, the processor controls the throttle valve to close, controls the indoor fan and compressor to start, and controls the four-way valve to switch to the working state of heating flow direction.

[0067] S404, when the first preset switching condition is met, the processor controls the indoor fan and the compressor to stop, and controls the four-way valve to switch to the working state of the cooling flow direction.

[0068] S405, the processor controls the heating device to start heating to heat the liquid refrigerant in the compressor into gaseous refrigerant.

[0069] The method for controlling an air conditioner provided by the embodiment of the present disclosure is adopted to determine whether the preset oil return condition is met by detecting relevant parameters inside the air conditioner. If the preset oil return condition is met, it is determined that the current time is appropriate, and the embodiment of the present disclosure starts to execute the oil return program. Since the air conditioner is in different operating conditions, there are certain differences in the retention points of the lubricating oil, so there may be multiple situations where the lubricating oil is more accumulated in the indoor heat exchanger or more accumulated in the outdoor heat exchanger. By comparing the pipe wall thickness of the indoor heat exchanger and the pipe wall thickness of the outdoor heat exchanger, the embodiment of the present disclosure can determine the main accumulation position of the lubricating oil in the refrigerant circulation loop to determine which lubricating oil accumulation situation the air conditioner is currently in. And corresponding to the different accumulation situations of the lubricating oil, the embodiment of the present disclosure can provide differentiated oil return modes to ensure the oil return effect in various situations. By executing the most suitable oil return mode in the current situation, the embodiment of the present disclosure can ensure that more lubricating oil can be stably recovered, thereby increasing the recovery amount of lubricating oil, which is conducive to optimizing the oil return performance. Specifically, when it is determined that the pipe wall thickness of the indoor heat exchanger is greater than or equal to the pipe wall thickness of the outdoor heat exchanger, it indicates that the current lubricating oil is mainly retained at the indoor heat exchanger. For this reason, the air conditioner executes the first oil return mode. First, the throttle valve is controlled to be closed. The disclosed embodiment enables the indoor heat exchanger to no longer transport liquid refrigerant to the outdoor heat exchanger. Then the indoor fan and the compressor are controlled to start, and the four-way valve is controlled to switch to the working state of the heating flow direction. The disclosed embodiment enables the refrigerant in the outdoor heat exchanger and its connected pipelines to be driven by the compressor to flow to the indoor heat exchanger, so that the refrigerant near the outdoor heat exchanger and the compressor can be transferred to the indoor heat exchanger. And along with the normal operation of the indoor fan, the gaseous refrigerant entering the indoor heat exchanger will be converted into liquid refrigerant due to condensation heat release and stored in the indoor heat exchanger pipeline. At this time, the outdoor heat exchanger and the compressor will gradually generate negative pressure because the refrigerant is transferred away. Inside the indoor heat exchanger, since the liquid refrigerant can be miscible with the lubricating oil, its ability to carry the lubricating oil is stronger, and the lubricating oil originally attached to the indoor heat exchanger tube wall is dissolved in the stored liquid refrigerant in large quantities. When it is judged that the first preset reversing condition is met, it means that the refrigerant in the refrigerant circulation loop has been basically transferred. At this time, the indoor fan and the compressor are controlled to stop to avoid the subsequent four-way valve from vaporizing the liquid refrigerant and causing the lubricating oil to precipitate again. Then the four-way valve is controlled to switch to the working state of the refrigeration flow direction. Under the negative pressure in the outdoor heat exchanger and the compressor, the liquid refrigerant carrying a large amount of lubricating oil will flow to the filter bottle inside the compressor. By controlling the heating device to start heating, the disclosed embodiment can heat the liquid refrigerant returned to the compressor to convert the liquid refrigerant in the compressor into a gaseous refrigerant. At this time, the ability of the refrigerant to carry the lubricating oil decreases, and the lubricating oil will gradually precipitate from the refrigerant and return to the compressor oil pool, thereby achieving the purpose of oil return of the air conditioner.Therefore, by executing the first oil return mode, the embodiment of the present disclosure can effectively recover a large amount of lubricating oil retained in the indoor heat exchanger to complete the oil return work to the compressor.

[0070] Optionally, the first preset reversing condition includes: the coil temperature of the indoor heat exchanger is greater than or equal to the first preset coil temperature. In this way, the first preset coil temperature can be measured by experiment. When the coil temperature of the indoor heat exchanger exceeds the first preset coil temperature, it indicates that a sufficient amount of gaseous refrigerant has been converted into liquid refrigerant through condensation heat release and stored in the indoor heat exchanger pipeline. At this time, this part of the liquid refrigerant can be miscible with the lubricating oil, so that the lubricating oil originally attached to the indoor heat exchanger tube wall is dissolved in a large amount in the liquid refrigerant, so as to facilitate the recovery of the lubricating oil to the compressor and then precipitation.

[0071] Optionally, the first preset reversing condition includes: the rate of change of the coil temperature of the indoor heat exchanger is less than or equal to the first preset temperature change rate. In this way, the first preset temperature change rate can be measured by experiment. When the rate of change of the coil temperature of the indoor heat exchanger is less than or equal to the first preset temperature change rate, it indicates that most of the gaseous refrigerant has been converted into liquid refrigerant through condensation heat release and stored in the indoor heat exchanger pipeline. At this time, this part of the liquid refrigerant can be miscible with the lubricating oil, so that the lubricating oil originally attached to the indoor heat exchanger tube wall is dissolved in a large amount in the liquid refrigerant, so as to facilitate the recovery of the lubricating oil to the compressor and then precipitation.

[0072] Optionally, the first preset reversing condition includes: the operating time after the four-way valve is switched is greater than or equal to the first preset time. In this way, the first preset time can be measured by experiment. When the operating time after the four-way valve is switched exceeds the first preset time, it indicates that most of the gaseous refrigerant has been converted into liquid refrigerant through condensation heat release and stored in the indoor heat exchanger pipeline. At this time, this part of the liquid refrigerant can be miscible with the lubricating oil, so that the lubricating oil originally attached to the indoor heat exchanger tube wall is dissolved in a large amount in the liquid refrigerant, so as to facilitate the recovery of the lubricating oil to the compressor and then precipitation.

[0073] Optionally, the disclosed embodiment may also set other first preset reversing conditions, which are not limited to the above-mentioned judgment conditions. The first preset reversing condition may be set according to the specific operating conditions of the air conditioner to cope with more complex refrigerant transfer situations, which are not listed here one by one. At the same time, the first preset reversing condition may also be organically combined on the basis of the above-mentioned multiple judgment conditions to further improve the accuracy of determining the timing of the four-way valve reversing.

[0074] Optionally, the processor controls the heating device to start heating, including: the processor determines a first heating parameter of the heating device according to the pipe wall thickness of the indoor heat exchanger; the processor controls the heating device to operate according to the first heating parameter. In this way, by analyzing the pipe wall thickness of the indoor heat exchanger, the embodiment of the present disclosure can estimate the amount of lubricating oil accumulation, and by controlling the heating device to start operation with the most suitable heating parameter, the precipitation efficiency of the lubricating oil can be improved, ensuring that the lubricating oil can be stably recovered, which is conducive to optimizing the oil return performance.

[0075] Optionally, the pipe wall thickness of the indoor heat exchanger is positively correlated with the first heating parameter of the heating device. That is, the thicker the pipe wall thickness of the indoor heat exchanger is, the larger the first heating parameter of the heating device is. In this way, when the pipe wall thickness of the indoor heat exchanger is relatively large, it means that more lubricating oil is accumulated in the indoor heat exchanger pipe, and more lubricating oil enters the compressor with the liquid refrigerant in the subsequent oil return procedure. By selecting a larger heating parameter, the disclosed embodiment can increase the vaporization rate of the liquid refrigerant, thereby accelerating the precipitation efficiency of the lubricating oil, ensuring that the lubricating oil can be stably recovered, and is conducive to optimizing the oil return performance.

[0076] Optionally, the first heating parameter includes one or more of heating power, heating duration, and heating temperature. In this way, by adjusting the above heating parameters, the disclosed embodiment can adapt to different forms of heating devices and can reasonably control the vaporization rate of the liquid refrigerant inside the compressor, which is conducive to adjusting the precipitation efficiency of the lubricating oil, ensuring that the lubricating oil can be stably recovered, and is conducive to optimizing the oil return performance.

[0077] Based on the above air conditioner structure, combined with Figure 5 As shown, the embodiment of the present disclosure provides another method for controlling an air conditioner, comprising:

[0078] S501, when a preset oil return condition is met, the processor determines the pipe wall thickness of each heat exchanger.

[0079] S502: When the pipe wall thickness of the indoor heat exchanger is greater than or equal to the pipe wall thickness of the outdoor heat exchanger, the processor determines that the oil return mode of the air conditioner is the first oil return mode.

[0080] S503, the processor controls the throttle valve to close, controls the indoor fan and compressor to start, and controls the four-way valve to switch to the working state of heating flow direction.

[0081] S504: When the first preset switching condition is met, the processor controls the indoor fan and the compressor to stop, and controls the four-way valve to switch to a cooling flow working state.

[0082] S505, the processor controls the heating device to start heating to heat the liquid refrigerant in the compressor into gaseous refrigerant.

[0083] S506, when the first preset stop condition is met, the processor controls the heating device to stop heating, controls the throttle valve to open, and determines whether the air conditioner meets the first preset exit condition.

[0084] S507: If the first preset exit condition is not met, the air conditioner is controlled to execute the first oil return mode again, that is, jumping back to step S503.

[0085] S508: When a first preset exit condition is met, the processor controls the air conditioner to exit the first oil return mode.

[0086] The method for controlling an air conditioner provided by the embodiment of the present disclosure is adopted to determine whether the preset oil return condition is met by detecting relevant parameters inside the air conditioner. If the preset oil return condition is met, it is determined that the current time is appropriate, and the embodiment of the present disclosure starts to execute the oil return program. Since the air conditioner is in different operating conditions, there are certain differences in the retention points of the lubricating oil, so there may be multiple situations where the lubricating oil is more accumulated in the indoor heat exchanger or more accumulated in the outdoor heat exchanger. By comparing the pipe wall thickness of the indoor heat exchanger and the pipe wall thickness of the outdoor heat exchanger, the embodiment of the present disclosure can determine the main accumulation position of the lubricating oil in the refrigerant circulation loop to determine which lubricating oil accumulation situation the air conditioner is currently in. And corresponding to the different accumulation situations of the lubricating oil, the embodiment of the present disclosure can provide differentiated oil return modes to ensure the oil return effect in various situations. By executing the most suitable oil return mode in the current situation, the embodiment of the present disclosure can ensure that more lubricating oil can be stably recovered, thereby increasing the recovery amount of lubricating oil, which is conducive to optimizing the oil return performance. Specifically, when it is determined that the pipe wall thickness of the indoor heat exchanger is greater than or equal to the pipe wall thickness of the outdoor heat exchanger, it indicates that the current lubricating oil is mainly retained at the indoor heat exchanger. For this reason, the air conditioner executes the first oil return mode. First, the throttle valve is controlled to be closed. The disclosed embodiment enables the indoor heat exchanger to no longer transport liquid refrigerant to the outdoor heat exchanger. Then the indoor fan and the compressor are controlled to start, and the four-way valve is controlled to switch to the working state of the heating flow direction. The disclosed embodiment enables the refrigerant in the outdoor heat exchanger and its connected pipelines to be driven by the compressor to flow to the indoor heat exchanger, so that the refrigerant near the outdoor heat exchanger and the compressor can be transferred to the indoor heat exchanger. And along with the normal operation of the indoor fan, the gaseous refrigerant entering the indoor heat exchanger will be converted into liquid refrigerant due to condensation heat release and stored in the indoor heat exchanger pipeline. At this time, the outdoor heat exchanger and the compressor will gradually generate negative pressure because the refrigerant is transferred away. Inside the indoor heat exchanger, since the liquid refrigerant can be miscible with the lubricating oil, its ability to carry the lubricating oil is stronger, and the lubricating oil originally attached to the indoor heat exchanger tube wall is dissolved in the stored liquid refrigerant in large quantities. When it is judged that the first preset reversing condition is met, it means that the refrigerant in the refrigerant circulation loop has been basically transferred. At this time, the indoor fan and the compressor are controlled to stop to avoid the subsequent four-way valve from vaporizing the liquid refrigerant and causing the lubricating oil to precipitate again. Then the four-way valve is controlled to switch to the working state of the refrigeration flow direction. Under the negative pressure in the outdoor heat exchanger and the compressor, the liquid refrigerant carrying a large amount of lubricating oil will flow to the filter bottle inside the compressor. By controlling the heating device to start heating, the disclosed embodiment can heat the liquid refrigerant returned to the compressor to convert the liquid refrigerant in the compressor into a gaseous refrigerant. At this time, the ability of the refrigerant to carry the lubricating oil decreases, and the lubricating oil will gradually precipitate from the refrigerant and return to the compressor oil pool, thereby achieving the purpose of oil return of the air conditioner.Thus, by executing the first oil return mode, the embodiment of the present disclosure can effectively recover a large amount of lubricating oil retained at the indoor heat exchanger to complete the oil return work of the compressor. After the air conditioner runs for a period of time according to the first oil return mode, the embodiment of the present disclosure determines whether the air conditioner meets the first preset stop condition. If it meets, the heating device is controlled to stop heating, and the throttle valve is controlled to open to balance the system pressure, which is conducive to the subsequent normal operation of the air conditioner. At the same time, the embodiment of the present disclosure further determines whether the air conditioner meets the first preset exit condition. If it does not meet, it means that the lubricating oil has not been completely recovered. At this time, the lubricating oil inside the compressor is still not enough to support the normal operation of the compressor, and the first oil return mode is executed again to ensure that more lubricating oil in the refrigerant circulation loop can be brought back to the compressor by the refrigerant. If it meets, it means that the lubricating oil at the indoor heat exchanger has been basically recovered. At this time, the lubricating oil inside the compressor is sufficient to support the normal operation of the compressor, so the embodiment of the present disclosure exits the oil return program and no longer executes the first oil return mode. Thus, the embodiment of the present disclosure can increase the recovery amount of lubricating oil by running the first oil return mode multiple times, which is conducive to further optimizing the oil return performance. This ensures that the compressor can operate normally and helps improve the reliability of the oil return program.

[0087] Optionally, the first preset stop condition includes: the change rate of the pressure in the compressor filter bottle is less than or equal to the first preset pressure change rate. In this way, the first preset pressure change rate can be measured by experiment. When the change rate of the pressure in the compressor filter bottle is less than or equal to the first preset pressure change rate, it indicates that most of the liquid refrigerant in the current compressor filter bottle has been converted into gaseous refrigerant by heating, and the lubricating oil carried by it has been precipitated to be discharged back to the oil pool inside the compressor. At this time, continued heating will no longer increase the amount of lubricating oil precipitated, so the heating device is controlled to stop heating to return the air conditioner to normal operating conditions.

[0088] Optionally, the first preset exit condition includes: the lubricating oil level of the compressor is greater than the preset level. Thus, when the lubricating oil level exceeds the preset level, it indicates that the current lubricating oil content in the compressor is sufficient to effectively lubricate the compressor to support the normal operation of the compressor. Therefore, the embodiment of the present disclosure exits the oil return program and no longer executes the first oil return mode, so that the air conditioner returns to normal operating conditions as soon as possible, which is conducive to ensuring the user experience.

[0089] Optionally, the first preset exit condition includes: the pipe wall thickness of the indoor heat exchanger is less than the first preset thickness. In this way, when the pipe wall thickness of the indoor heat exchanger no longer exceeds the first preset thickness, it indicates that a large amount of lubricating oil has left the indoor heat exchanger pipe and returned to the compressor. At this time, the lubricating oil has been basically recovered, and the lubricating oil inside the compressor is sufficient to support the normal operation of the compressor. Therefore, the embodiment of the present disclosure exits the oil return program and no longer executes the first oil return mode, so that the air conditioner returns to normal operating conditions as soon as possible, which is conducive to ensuring the user experience.

[0090] Optionally, the disclosed embodiment may also set other first preset exit conditions, which are not limited to the above-mentioned judgment conditions. The first preset exit condition may be set according to the specific operating conditions of the air conditioner to cope with more complex lubricating oil recovery conditions, which are not listed here one by one. At the same time, the first preset exit condition may also be organically combined on the basis of the above-mentioned multiple judgment conditions to further improve the accuracy of determining the exit timing of the oil return program.

[0091] Based on the above air conditioner structure, combined with Figure 6 As shown, the embodiment of the present disclosure provides another method for controlling an air conditioner, comprising:

[0092] S601, when a preset oil return condition is met, the processor determines the pipe wall thickness of each heat exchanger.

[0093] S602: When the pipe wall thickness of the indoor heat exchanger is smaller than the pipe wall thickness of the outdoor heat exchanger, the processor determines that the oil return mode of the air conditioner is the second oil return mode.

[0094] S603, the processor controls the throttle valve to close, controls the outdoor fan and the compressor to start, and controls the four-way valve to switch to the working state of the cooling flow direction.

[0095] S604: When the second preset switching condition is met, the processor controls the outdoor fan and the compressor to stop, and controls the four-way valve to switch to a heating flow working state.

[0096] S605, the processor controls the heating device to start heating to heat the liquid refrigerant in the compressor into gaseous refrigerant.

[0097] The method for controlling an air conditioner provided by the embodiment of the present disclosure is adopted to determine whether the preset oil return condition is met by detecting relevant parameters inside the air conditioner. If the preset oil return condition is met, it is determined that the current time is appropriate, and the embodiment of the present disclosure starts to execute the oil return program. Since the air conditioner is in different operating conditions, there are certain differences in the retention points of the lubricating oil, so there may be multiple situations where the lubricating oil is more accumulated in the indoor heat exchanger or more accumulated in the outdoor heat exchanger. By comparing the pipe wall thickness of the indoor heat exchanger and the pipe wall thickness of the outdoor heat exchanger, the embodiment of the present disclosure can determine the main accumulation position of the lubricating oil in the refrigerant circulation loop to determine which lubricating oil accumulation situation the air conditioner is currently in. And corresponding to the different accumulation situations of the lubricating oil, the embodiment of the present disclosure can provide differentiated oil return modes to ensure the oil return effect in various situations. By executing the most suitable oil return mode in the current situation, the embodiment of the present disclosure can ensure that more lubricating oil can be stably recovered, thereby increasing the recovery amount of lubricating oil, which is conducive to optimizing the oil return performance. Specifically, when it is determined that the pipe wall thickness of the indoor heat exchanger is less than the pipe wall thickness of the outdoor heat exchanger, it indicates that the current lubricating oil is mainly retained at the outdoor heat exchanger. For this reason, the air conditioner executes the second oil return mode. First, the throttle valve is controlled to be closed. The disclosed embodiment enables the outdoor heat exchanger to no longer transport liquid refrigerant to the indoor heat exchanger. Then the outdoor fan and the compressor are controlled to start, and the four-way valve is controlled to switch to the working state of the refrigeration flow direction. The disclosed embodiment enables the refrigerant in the indoor heat exchanger and its connected pipelines to be driven by the compressor to flow to the outdoor heat exchanger, so that the refrigerant near the indoor heat exchanger and the compressor can be transferred to the outdoor heat exchanger. And with the normal operation of the outdoor fan, the gaseous refrigerant entering the outdoor heat exchanger will be converted into liquid refrigerant due to condensation heat release and stored in the outdoor heat exchanger pipeline. At this time, the indoor heat exchanger and the compressor will gradually generate negative pressure because the refrigerant is transferred away. Inside the outdoor heat exchanger, since the liquid refrigerant can be miscible with the lubricating oil, its ability to carry the lubricating oil is stronger, and the lubricating oil originally attached to the wall of the outdoor heat exchanger tube is dissolved in the stored liquid refrigerant in large quantities. When it is judged that the second preset reversing condition is met, it means that the refrigerant in the refrigerant circulation loop has been basically transferred. At this time, the outdoor fan and the compressor are controlled to stop to avoid the subsequent four-way valve from vaporizing the liquid refrigerant and causing the lubricating oil to precipitate again. Then the four-way valve is controlled to switch to the working state of the heating flow direction. Under the negative pressure in the indoor heat exchanger and the compressor, the liquid refrigerant carrying a large amount of lubricating oil will flow to the filter bottle inside the compressor. By controlling the heating device to start heating, the disclosed embodiment can heat the liquid refrigerant returned to the compressor to convert the liquid refrigerant in the compressor into a gaseous refrigerant. At this time, the ability of the refrigerant to carry the lubricating oil decreases, and the lubricating oil will gradually precipitate from the refrigerant and return to the compressor oil pool, thereby achieving the purpose of oil return of the air conditioner.Therefore, by executing the second oil return mode, the embodiment of the present disclosure can effectively recover a large amount of lubricating oil retained at the outdoor heat exchanger to complete the oil return work to the compressor.

[0098] Optionally, the second preset reversing condition includes: the coil temperature of the outdoor heat exchanger is greater than or equal to the second preset coil temperature. In this way, the second preset coil temperature can be measured by experiment. When the coil temperature of the outdoor heat exchanger exceeds the second preset coil temperature, it indicates that a sufficient amount of gaseous refrigerant has been converted into liquid refrigerant through condensation heat release and stored in the outdoor heat exchanger pipeline. At this time, this part of the liquid refrigerant can be miscible with the lubricating oil, so that the lubricating oil originally attached to the wall of the outdoor heat exchanger tube is dissolved in the liquid refrigerant in large quantities, so as to facilitate the recovery of the lubricating oil to the compressor and then precipitation.

[0099] Optionally, the second preset reversing condition includes: the change rate of the coil temperature of the outdoor heat exchanger is less than or equal to the second preset temperature change rate. In this way, the second preset temperature change rate can be measured by experiment. When the change rate of the coil temperature of the outdoor heat exchanger is less than or equal to the second preset temperature change rate, it indicates that most of the gaseous refrigerant has been converted into liquid refrigerant through condensation heat release and stored in the outdoor heat exchanger pipeline. At this time, this part of the liquid refrigerant can be miscible with the lubricating oil, so that the lubricating oil originally attached to the wall of the outdoor heat exchanger tube is dissolved in the liquid refrigerant in large quantities, so as to facilitate the recovery of the lubricating oil to the compressor and then precipitation.

[0100] Optionally, the second preset reversing condition includes: the operating time after the four-way valve is switched is greater than or equal to the second preset time. In this way, the second preset time can be measured by experiment. When the operating time after the four-way valve is switched exceeds the second preset time, it indicates that most of the gaseous refrigerant has been converted into liquid refrigerant through condensation heat release and stored in the outdoor heat exchanger pipeline. At this time, this part of the liquid refrigerant can be miscible with the lubricating oil, so that the lubricating oil originally attached to the wall of the outdoor heat exchanger tube is dissolved in a large amount in the liquid refrigerant, so as to facilitate the recovery of the lubricating oil to the compressor and then precipitation.

[0101] Optionally, the disclosed embodiment may also set other second preset reversing conditions, which are not limited to the above-mentioned judgment conditions. The second preset reversing condition may be set according to the specific operating conditions of the air conditioner to cope with more complex refrigerant transfer situations, which are not listed here one by one. At the same time, the second preset reversing condition may also be organically combined on the basis of the above-mentioned multiple judgment conditions to further improve the accuracy of determining the timing of the four-way valve reversing.

[0102] Optionally, the processor controls the heating device to start heating, including: the processor determines a second heating parameter of the heating device according to the pipe wall thickness of the outdoor heat exchanger; the processor controls the heating device to operate according to the second heating parameter. In this way, by analyzing the pipe wall thickness of the outdoor heat exchanger, the embodiment of the present disclosure can estimate the amount of lubricating oil accumulation, and by controlling the heating device to start operation with the most suitable heating parameter, the precipitation efficiency of the lubricating oil can be improved, ensuring that the lubricating oil can be stably recovered, which is conducive to optimizing the oil return performance.

[0103] Optionally, the pipe wall thickness of the outdoor heat exchanger is positively correlated with the second heating parameter of the heating device. That is, the thicker the pipe wall thickness of the outdoor heat exchanger is, the larger the second heating parameter of the heating device is. In this way, when the pipe wall thickness of the outdoor heat exchanger is relatively large, it means that more lubricating oil is accumulated in the outdoor heat exchanger pipe, and more lubricating oil enters the compressor with the liquid refrigerant in the subsequent oil return procedure. By selecting a larger heating parameter, the embodiment of the present disclosure can increase the vaporization rate of the liquid refrigerant, thereby accelerating the precipitation efficiency of the lubricating oil, ensuring that the lubricating oil can be stably recovered, and is conducive to optimizing the oil return performance.

[0104] Optionally, the second heating parameter includes one or more of heating power, heating duration, and heating temperature. In this way, by adjusting the above heating parameters, the disclosed embodiment can adapt to different forms of heating devices and can reasonably control the vaporization rate of the liquid refrigerant inside the compressor, which is conducive to adjusting the precipitation efficiency of the lubricating oil, ensuring that the lubricating oil can be stably recovered, and is conducive to optimizing the oil return performance.

[0105] Based on the above air conditioner structure, combined with Figure 7 As shown, the embodiment of the present disclosure provides another method for controlling an air conditioner, comprising:

[0106] S701, when a preset oil return condition is met, the processor determines the pipe wall thickness of each heat exchanger.

[0107] S702: When the pipe wall thickness of the indoor heat exchanger is smaller than the pipe wall thickness of the outdoor heat exchanger, the processor determines that the oil return mode of the air conditioner is the second oil return mode.

[0108] S703, the processor controls the throttle valve to close, controls the outdoor fan and the compressor to start, and controls the four-way valve to switch to the working state of the cooling flow direction.

[0109] S704: When the second preset switching condition is met, the processor controls the outdoor fan and the compressor to stop, and controls the four-way valve to switch to a heating flow working state.

[0110] S705, the processor controls the heating device to start heating to heat the liquid refrigerant in the compressor into gaseous refrigerant.

[0111] S706, when the second preset stop condition is met, the processor controls the heating device to stop heating, controls the throttle valve to open, and determines whether the air conditioner meets the second preset exit condition.

[0112] S707: If the second preset exit condition is not met, the processor controls the air conditioner to execute the second oil return mode again, that is, jump back to step S703.

[0113] S708: When the second preset exit condition is met, the processor controls the air conditioner to exit the second oil return mode.

[0114] The method for controlling an air conditioner provided by the embodiment of the present disclosure is adopted to determine whether the preset oil return condition is met by detecting relevant parameters inside the air conditioner. If the preset oil return condition is met, it is determined that the current time is appropriate, and the embodiment of the present disclosure starts to execute the oil return program. Since the air conditioner is in different operating conditions, there are certain differences in the retention points of the lubricating oil, so there may be multiple situations where the lubricating oil is more accumulated in the indoor heat exchanger or more accumulated in the outdoor heat exchanger. By comparing the pipe wall thickness of the indoor heat exchanger and the pipe wall thickness of the outdoor heat exchanger, the embodiment of the present disclosure can determine the main accumulation position of the lubricating oil in the refrigerant circulation loop to determine which lubricating oil accumulation situation the air conditioner is currently in. And corresponding to the different accumulation situations of the lubricating oil, the embodiment of the present disclosure can provide differentiated oil return modes to ensure the oil return effect in various situations. By executing the most suitable oil return mode in the current situation, the embodiment of the present disclosure can ensure that more lubricating oil can be stably recovered, thereby increasing the recovery amount of lubricating oil, which is conducive to optimizing the oil return performance. Specifically, when it is determined that the pipe wall thickness of the indoor heat exchanger is less than the pipe wall thickness of the outdoor heat exchanger, it indicates that the current lubricating oil is mainly retained at the outdoor heat exchanger. For this reason, the air conditioner executes the second oil return mode. First, the throttle valve is controlled to be closed. The disclosed embodiment enables the outdoor heat exchanger to no longer transport liquid refrigerant to the indoor heat exchanger. Then the outdoor fan and the compressor are controlled to start, and the four-way valve is controlled to switch to the working state of the refrigeration flow direction. The disclosed embodiment enables the refrigerant in the indoor heat exchanger and its connected pipelines to be driven by the compressor to flow to the outdoor heat exchanger, so that the refrigerant near the indoor heat exchanger and the compressor can be transferred to the outdoor heat exchanger. And with the normal operation of the outdoor fan, the gaseous refrigerant entering the outdoor heat exchanger will be converted into liquid refrigerant due to condensation heat release and stored in the outdoor heat exchanger pipeline. At this time, the indoor heat exchanger and the compressor will gradually generate negative pressure because the refrigerant is transferred away. Inside the outdoor heat exchanger, since the liquid refrigerant can be miscible with the lubricating oil, its ability to carry the lubricating oil is stronger, and the lubricating oil originally attached to the wall of the outdoor heat exchanger tube is dissolved in the stored liquid refrigerant in large quantities. When it is judged that the second preset reversing condition is met, it means that the refrigerant in the refrigerant circulation loop has been basically transferred. At this time, the outdoor fan and the compressor are controlled to stop to avoid the subsequent four-way valve from vaporizing the liquid refrigerant and causing the lubricating oil to precipitate again. Then the four-way valve is controlled to switch to the working state of the heating flow direction. Under the negative pressure in the indoor heat exchanger and the compressor, the liquid refrigerant carrying a large amount of lubricating oil will flow to the filter bottle inside the compressor. By controlling the heating device to start heating, the disclosed embodiment can heat the liquid refrigerant returned to the compressor to convert the liquid refrigerant in the compressor into a gaseous refrigerant. At this time, the ability of the refrigerant to carry the lubricating oil decreases, and the lubricating oil will gradually precipitate from the refrigerant and return to the compressor oil pool, thereby achieving the purpose of oil return of the air conditioner.Thus, by executing the second oil return mode, the embodiment of the present disclosure can effectively recover a large amount of lubricating oil retained at the outdoor heat exchanger to complete the oil return work of the compressor. After the air conditioner runs for a period of time according to the second oil return mode, the embodiment of the present disclosure determines whether the air conditioner meets the second preset stop condition. If it meets, the heating device is controlled to stop heating, and the throttle valve is controlled to open to balance the system pressure, which is conducive to the subsequent normal operation of the air conditioner. At the same time, the embodiment of the present disclosure further determines whether the air conditioner meets the second preset exit condition. If it does not meet, it means that the lubricating oil has not been completely recovered. At this time, the lubricating oil inside the compressor is still not enough to support the normal operation of the compressor, and the second oil return mode is executed again to ensure that more lubricating oil in the refrigerant circulation loop can be brought back to the compressor by the refrigerant. If it meets, it means that the lubricating oil at the outdoor heat exchanger has been basically recovered. At this time, the lubricating oil inside the compressor is sufficient to support the normal operation of the compressor, so the embodiment of the present disclosure exits the oil return program and no longer executes the second oil return mode. Thus, the embodiment of the present disclosure can increase the recovery amount of lubricating oil by running the second oil return mode multiple times, which is conducive to further optimizing the oil return performance. This ensures that the compressor can operate normally and helps improve the reliability of the oil return program.

[0115] Optionally, the second preset stop condition includes: the change rate of the pressure in the compressor filter bottle is less than or equal to the second preset pressure change rate. In this way, the second preset pressure change rate can be measured by experiment. When the change rate of the pressure in the compressor filter bottle is less than or equal to the second preset pressure change rate, it indicates that most of the liquid refrigerant in the current compressor filter bottle has been converted into gaseous refrigerant by heating, and the lubricating oil carried by it has been precipitated to be discharged back to the oil pool inside the compressor. At this time, continued heating will no longer increase the amount of lubricating oil precipitated, so the heating device is controlled to stop heating to return the air conditioner to normal operating conditions.

[0116] Optionally, the second preset exit condition includes: the lubricating oil level of the compressor is greater than the preset level. Thus, when the lubricating oil level exceeds the preset level, it indicates that the current lubricating oil content in the compressor is sufficient to effectively lubricate the compressor to support the normal operation of the compressor. Therefore, the disclosed embodiment exits the oil return program and no longer executes the second oil return mode, so that the air conditioner returns to normal operating conditions as soon as possible, which is conducive to ensuring the user experience.

[0117] Optionally, the second preset exit condition includes: the pipe wall thickness of the outdoor heat exchanger is less than the second preset thickness. In this way, when the pipe wall thickness of the outdoor heat exchanger no longer exceeds the second preset thickness, it indicates that a large amount of lubricating oil has left the outdoor heat exchanger pipe and returned to the compressor. At this time, the lubricating oil has been basically recovered, and the lubricating oil inside the compressor is sufficient to support the normal operation of the compressor. Therefore, the embodiment of the present disclosure exits the oil return program and no longer executes the second oil return mode, so that the air conditioner returns to normal operating conditions as soon as possible, which is conducive to ensuring the user experience.

[0118] Optionally, the disclosed embodiment may also set other second preset exit conditions, which are not limited to the above-mentioned judgment conditions. The second preset exit condition may be set according to the specific operating conditions of the air conditioner to cope with more complex lubricating oil recovery conditions, which are not listed here one by one. At the same time, the second preset exit condition may also be organically combined on the basis of the above-mentioned multiple judgment conditions to further improve the accuracy of determining the exit timing of the oil return program.

[0119] Combination Figure 8 As shown, the embodiment of the present disclosure provides a device 800 for controlling an air conditioner, including a processor 801 and a memory 802. Optionally, the device may also include a communication interface 803 and a bus 804. The processor 801, the communication interface 803, and the memory 802 may communicate with each other through the bus 804. The communication interface 803 may be used for information transmission. The processor 801 may call the logic instructions in the memory 802 to execute the method for controlling the air conditioner of the above embodiment.

[0120] In addition, the logic instructions in the memory 802 described above may be implemented in the form of software functional units and when sold or used as independent products, may be stored in a computer-readable storage medium.

[0121] The memory 802 is a computer-readable storage medium that can be used to store software programs and computer executable programs, such as program instructions / modules corresponding to the method in the embodiment of the present disclosure. The processor 801 executes the function application and data processing by running the program instructions / modules stored in the memory 802, that is, the method for controlling the air conditioner in the above embodiment is implemented.

[0122] The memory 802 may include a program storage area and a data storage area, wherein the program storage area may store an operating system and an application required for at least one function; the data storage area may store data created according to the use of the terminal device, etc. In addition, the memory 802 may include a high-speed random access memory and may also include a non-volatile memory.

[0123] Optionally, the air conditioner provided in the embodiment of the present disclosure further includes: the above-mentioned device 800 for controlling the air conditioner. The device 800 for controlling the air conditioner is installed inside the air conditioner. The installation relationship described here is not limited to placement inside the product, but also includes installation connections with other components of the product, including but not limited to physical connections, electrical connections, or signal transmission connections. It can be understood by those skilled in the art that the device 800 for controlling the air conditioner can be adapted to a feasible product body, thereby realizing other feasible embodiments.

[0124] An embodiment of the present disclosure provides a computer-readable storage medium storing computer-executable instructions, wherein the computer-executable instructions are configured to execute the above-mentioned method for controlling an air conditioner.

[0125] The computer-readable storage medium mentioned above may be a transient computer-readable storage medium or a non-transitory computer-readable storage medium.

[0126] The technical solution of the embodiment of the present disclosure can be embodied in the form of a software product, which is stored in a storage medium and includes one or more instructions for enabling a computer device (which may be a personal computer, a server, or a network device, etc.) to perform all or part of the steps of the method described in the embodiment of the present disclosure. The aforementioned storage medium may be a non-transient storage medium, including: a USB flash drive, a mobile hard disk, a read-only memory (ROM), a random access memory (RAM), a magnetic disk or an optical disk, and other media that can store program codes, or a transient storage medium.

[0127] The above description and the accompanying drawings fully illustrate the embodiments of the present disclosure so that those skilled in the art can practice them. Other embodiments may include structural, logical, electrical, process and other changes. The embodiments represent only possible changes. Unless explicitly required, separate components and functions are optional, and the order of operation may vary. The parts and features of some embodiments may be included in or replace the parts and features of other embodiments. Moreover, the words used in this application are only used to describe the embodiments and are not used to limit the claims. As used in the description of the embodiments and the claims, unless the context clearly indicates, the singular forms of "a", "an" and "the" are intended to include plural forms as well. Similarly, the term "and / or" as used in this application refers to any and all possible combinations of listings containing one or more associated ones. In addition, when used in the present application, the term "comprise" and its variants "comprises" and / or comprising refer to the presence of stated features, wholes, steps, operations, elements, and / or components, but do not exclude the presence or addition of one or more other features, wholes, steps, operations, elements, components and / or groups thereof. In the absence of further restrictions, the elements defined by the sentence "comprising a ..." do not exclude the presence of other identical elements in the process, method or device comprising the elements. In this article, each embodiment may focus on the differences from other embodiments, and the same and similar parts between the various embodiments may refer to each other. For the methods, products, etc. disclosed in the embodiments, if they correspond to the method part disclosed in the embodiments, then the relevant parts can refer to the description of the method part.

[0128] Those skilled in the art will appreciate that the units and algorithm steps of each example described in conjunction with the embodiments disclosed herein can be implemented in electronic hardware, or a combination of computer software and electronic hardware. Whether these functions are performed in hardware or software may depend on the specific application and design constraints of the technical solution. The technicians may use different methods for each specific application to implement the described functions, but such implementations should not be considered to exceed the scope of the embodiments of the present disclosure. The technicians may clearly understand that, for the convenience and simplicity of description, the specific working processes of the systems, devices and units described above may refer to the corresponding processes in the aforementioned method embodiments, and will not be repeated here.

[0129] In the embodiments disclosed herein, the disclosed methods and products (including but not limited to devices, equipment, etc.) can be implemented in other ways. For example, the device embodiments described above are only schematic. For example, the division of the units can be only a logical function division. There may be other division methods in actual implementation, such as multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed. In addition, the coupling or direct coupling or communication connection between each other shown or discussed can be through some interfaces, indirect coupling or communication connection of devices or units, which can be electrical, mechanical or other forms. The units described as separate components may or may not be physically separated, and the components displayed as units may or may not be physical units, that is, they may be located in one place, or they may be distributed on multiple network units. Some or all of the units may be selected according to actual needs to implement this embodiment. In addition, each functional unit in the embodiment of the present disclosure may be integrated in a processing unit, or each unit may exist physically alone, or two or more units may be integrated in one unit.

[0130] The flowchart and block diagram in the accompanying drawings show the possible architecture, function and operation of the system, method and computer program product according to the embodiment of the present disclosure. In this regard, each box in the flowchart or block diagram can represent a module, a program segment or a part of the code, and the module, the program segment or a part of the code contains one or more executable instructions for realizing the specified logical function. In some alternative implementations, the functions marked in the box can also occur in a different order from the order marked in the accompanying drawings. For example, two consecutive boxes can actually be executed substantially in parallel, and they can sometimes be executed in the opposite order, which can depend on the functions involved. In the description corresponding to the flowchart and the block diagram in the accompanying drawings, the operations or steps corresponding to different boxes can also occur in a different order from the order disclosed in the description, and sometimes there is no specific order between different operations or steps. For example, two consecutive operations or steps can actually be executed substantially in parallel, and they can sometimes be executed in the opposite order, which can depend on the functions involved. Each block in the block diagrams and / or flowcharts, and combinations of blocks in the block diagrams and / or flowcharts, may be implemented by a dedicated hardware-based system that performs the specified functions or actions, or may be implemented by a combination of dedicated hardware and computer instructions.

Claims

1. A method for controlling an air conditioner, characterized in that: include: Under the condition of meeting the preset oil return conditions, determine the pipe wall thickness of each heat exchanger; Determine the oil return mode of the air conditioner according to the pipe wall thickness of each heat exchanger; Controlling the air conditioner to execute the oil return mode; Wherein, determining the oil return mode of the air conditioner according to the pipe wall thickness of each heat exchanger includes: When the pipe wall thickness of the indoor heat exchanger is greater than or equal to the pipe wall thickness of the outdoor heat exchanger, determining the oil return mode of the air conditioner to be the first oil return mode; When the pipe wall thickness of the indoor heat exchanger is less than the pipe wall thickness of the outdoor heat exchanger, determining the oil return mode of the air conditioner to be the second oil return mode; A heating device is provided in the compressor; the air conditioner is controlled to execute the first oil return mode, including: controlling the throttle valve to close, controlling the indoor fan and the compressor to start, and controlling the four-way valve to switch to a working state of a heating flow direction; when the first preset reversing condition is met, controlling the indoor fan and the compressor to stop, and controlling the four-way valve to switch to a working state of a cooling flow direction; controlling the heating device to start heating, so as to heat the liquid refrigerant in the compressor into a gaseous refrigerant; Controlling the air conditioner to execute the second oil return mode includes: controlling the throttle valve to close, controlling the outdoor fan and the compressor to start, and controlling the four-way valve to switch to the working state of the cooling flow direction; when the second preset reversing condition is met, controlling the outdoor fan and the compressor to stop, and controlling the four-way valve to switch to the working state of the heating flow direction; controlling the heating device to start heating to heat the liquid refrigerant in the compressor into gaseous refrigerant.

2. The method according to claim 1, characterized in that After the controlling the heating device starts heating to heat the liquid refrigerant in the compressor into a gaseous refrigerant, the method further comprises: When the first preset stop condition is met, the heating device is controlled to stop heating, the throttle valve is controlled to open, and it is determined whether the air conditioner meets the first preset exit condition; When the first preset exit condition is not met, controlling the air conditioner to execute the first oil return mode again; When a first preset exit condition is met, the air conditioner is controlled to exit the first oil return mode.

3. The method according to claim 1, characterized in that: After the controlling the heating device starts heating to heat the liquid refrigerant in the compressor into a gaseous refrigerant, the method further comprises: When the second preset stop condition is met, the heating device is controlled to stop heating, the throttle valve is controlled to open, and it is determined whether the air conditioner meets the second preset exit condition; When the second preset exit condition is not met, controlling the air conditioner to execute the second oil return mode again; When the second preset exit condition is met, the air conditioner is controlled to exit the second oil return mode.

4. The method according to any one of claims 1 to 3, characterized in that: The preset oil return conditions include: The lubricating oil level of the compressor is less than or equal to a preset level; and / or, The pipe wall thickness of the indoor heat exchanger is greater than or equal to a first preset thickness; and / or, The pipe wall thickness of the outdoor heat exchanger is greater than or equal to a second preset thickness; and / or, The sum of the pipe wall thickness of the indoor heat exchanger and the pipe wall thickness of the outdoor heat exchanger is greater than or equal to a third preset thickness.

5. A device for controlling an air conditioner, comprising a processor and a memory storing program instructions, characterized in that: The processor is configured to execute the method for controlling an air conditioner according to any one of claims 1 to 4 when running the program instructions.

6. An air conditioner, characterized in that: include: The refrigerant circulation loop is composed of a compressor, a four-way valve, an indoor heat exchanger, a throttle valve and an outdoor heat exchanger connected by a refrigerant pipeline; Indoor fan, corresponding to the indoor heat exchanger setting; The outdoor fan is set corresponding to the outdoor heat exchanger; A heating device is provided in the compressor to heat the liquid refrigerant in the compressor; and, The device for controlling an air conditioner as claimed in claim 5.

7. A storage medium storing program instructions, characterized in that: When the program instructions are executed, the method for controlling an air conditioner according to any one of claims 1 to 4 is executed.

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