Control method of air conditioner, air conditioner and computer readable storage medium

Abstract

The application discloses a control method of an air conditioner, the air conditioner and a computer readable storage medium. The air conditioner comprises a compressor, an oil separator, a first indoor heat exchanger and a gas-liquid separator, a refrigerant outlet of the first indoor heat exchanger is communicated with a gas-liquid inlet of the gas-liquid separator, an oil outlet of the oil separator is communicated with the compressor through a first branch, a second branch parallel to the first branch is heat exchange connected with a gas outlet pipe of the gas-liquid separator, and a flow direction control module is used for controlling the flow of the compressor oil flowing out of the oil outlet in the first branch and the second branch. The method comprises the following steps: when the air conditioner is in refrigeration operation, the ambient temperature of the environment where the air conditioner is located is acquired; when the ambient temperature is greater than or equal to a preset temperature threshold, the compressor oil flowing out of the oil outlet is controlled to flow through the second branch and enter an oil return port through the flow direction control module. The application aims to reduce the working temperature of the compressor, improve the operation reliability of the compressor and improve the refrigerating capacity of the air conditioner.

Description

Technical Field

[0001] This invention relates to the field of air conditioning technology, and more particularly to a control method for an air conditioner, an air conditioner, and a computer-readable storage medium. Background Technology

[0002] With the development of economy and technology, and the continuous improvement of people's living standards, the application scenarios of air conditioners with indoor environment control functions are becoming more and more widespread.

[0003] Currently, air conditioners often need to operate in high-temperature environments. The air conditioner compressor is usually located outdoors. When the air conditioner is cooling, the outdoor unit is in a heat-releasing state, which can easily cause the compressor to operate at a high temperature. Excessive compressor operating temperature will not only reduce the cooling capacity of the air conditioner, but also easily damage the compressor and affect its reliability. Summary of the Invention

[0004] The main objective of this invention is to provide a control method for an air conditioner, an air conditioner, and a computer-readable storage medium, which aims to reduce the operating temperature of the compressor to improve the reliability of compressor operation and increase the cooling capacity of the air conditioner.

[0005] To achieve the above objectives, the present invention provides a control method for an air conditioner. The air conditioner includes a compressor, an oil separator, a first indoor heat exchanger, and a gas-liquid separator. The refrigerant outlet of the first indoor heat exchanger is connected to the gas-liquid inlet of the gas-liquid separator. The oil outlet of the oil separator is connected to the oil return port of the compressor via a first branch. The air conditioner further includes a flow direction control module and a second branch connected in parallel with the first branch. The second branch is heat-exchange connected to the gas outlet pipe of the gas-liquid separator. The flow direction control module is used to control the flow direction of the compressor oil flowing out of the oil outlet in the first branch and the second branch. The control method for the air conditioner includes the following steps:

[0006] When the air conditioner is in cooling mode, the ambient temperature of the environment where the air conditioner is located is obtained;

[0007] When the ambient temperature is greater than or equal to a preset temperature threshold, the flow direction control module is controlled to operate so that the compressor oil flowing out of the oil outlet flows through the second branch and exchanges heat with the outlet pipe before entering the return oil port.

[0008] Optionally, the flow direction control module includes a first control valve located on the first branch and a second control valve located on the second branch. The step of controlling the operation of the flow direction control module so that the compressor oil flowing out of the oil outlet flows through the second branch and exchanges heat with the outlet pipe before entering the oil return port includes:

[0009] The first control valve is closed, and the second control valve is opened.

[0010] Optionally, after the steps of controlling the first control valve to close and controlling the second control valve to open, the method further includes:

[0011] Obtain the first return oil temperature of the compressor;

[0012] The first opening control parameter of the first control valve and the second opening control parameter of the second control valve are determined based on the first return oil temperature.

[0013] The first control valve is controlled to operate with the first opening control parameter, and the second control valve is controlled to operate with the second opening control parameter, so that the temperature of the compressor oil return is within the target temperature range.

[0014] Optionally, the step of determining the first opening control parameter of the first control valve and the second opening control parameter of the second control valve based on the first return oil temperature includes:

[0015] When the first return oil temperature is less than the minimum value of the target temperature range, determining the first opening control parameter includes opening the first control valve, and determining the second opening control parameter includes closing the second control valve.

[0016] When the first return oil temperature is greater than the maximum value of the target temperature range, the temperature difference between the first return oil temperature and the maximum value is determined, and the first opening control parameter and the second opening control parameter are determined based on the temperature difference.

[0017] Optionally, the first opening control parameter further includes a first target opening of the first control valve, and the second opening control parameter includes a second target opening of the second control valve. The step of determining the first opening control parameter and the second opening control parameter based on the temperature difference value includes:

[0018] The first target opening and the second target opening are determined based on the temperature difference value;

[0019] The first target opening degree is negatively correlated with the temperature difference value, while the second target opening degree is positively correlated with the temperature difference value.

[0020] Optionally, after the steps of controlling the first control valve to close and controlling the second control valve to open, the method further includes:

[0021] Obtain the continuous operating time of the compressor after it starts;

[0022] When the continuous running time is greater than or equal to the preset duration, the step of obtaining the first oil return temperature of the compressor is performed.

[0023] Optionally, after the step of controlling the flow direction control module to operate when the ambient temperature is greater than or equal to a preset temperature threshold, so that the compressor oil flowing out of the oil outlet flows through the second branch and exchanges heat with the outlet pipe before entering the oil return port, the method further includes:

[0024] Obtain the second return oil temperature and the first discharge temperature of the compressor;

[0025] When the second return oil temperature is greater than the first preset temperature, and the first exhaust temperature is greater than the second preset temperature, the compressor is controlled to operate at a reduced frequency.

[0026] Optionally, the step of controlling the compressor to operate at a reduced frequency includes:

[0027] The compressor is controlled to operate at a reduced frequency at a first target rate, which is greater than a preset rate.

[0028] Optionally, after the step of controlling the compressor to operate at a reduced frequency, the method further includes:

[0029] Obtain the third oil return temperature and the second exhaust temperature of the compressor;

[0030] When the third return oil temperature is less than the third preset temperature and the second exhaust temperature is less than the fourth preset temperature, the compressor is controlled to operate at a second target rate.

[0031] Wherein, the third preset temperature is less than the first preset temperature, the fourth preset temperature is less than the second preset temperature, and the second target rate is less than or equal to the preset rate.

[0032] Optionally, after the step of obtaining the second return oil temperature and the first discharge temperature of the compressor, the method further includes:

[0033] When the second return oil temperature is greater than the fifth preset temperature and the first exhaust temperature is greater than the sixth preset temperature, the compressor is controlled to stop.

[0034] When the second return oil temperature is less than or equal to the fifth preset temperature, and / or when the first exhaust temperature is less than or equal to the sixth preset temperature, the step of controlling the compressor to operate at a reduced frequency at the first target rate when the second return oil temperature is greater than the first preset temperature and the first exhaust temperature is greater than the second preset temperature is executed.

[0035] The fifth preset temperature is greater than the first preset temperature, and the sixth preset temperature is greater than the second preset temperature.

[0036] Optionally, after the step of obtaining the ambient temperature of the environment where the air conditioner is located when the air conditioner is in cooling operation, the method further includes:

[0037] When the ambient temperature is lower than the preset temperature threshold, the flow direction control module is controlled to operate so that the compressor oil flowing out of the outlet flows through the first branch and enters the return oil port.

[0038] Optionally, the flow direction control module includes a first control valve located on the first branch and a second control valve located on the second branch. The step of controlling the operation of the flow direction control module to cause the compressor oil flowing out of the outlet to flow through the first branch and enter the return port includes:

[0039] The first control valve is opened, and the second control valve is closed.

[0040] Optionally, after the step of obtaining the ambient temperature of the environment where the air conditioner is located when the air conditioner is in cooling operation, the method further includes:

[0041] When the ambient temperature is greater than or equal to a preset temperature threshold, the outdoor fan of the air conditioner is controlled to run at a target speed, and the flow direction control module is executed to make the compressor oil flowing out of the oil outlet flow through the second branch and exchange heat with the outlet pipe before entering the oil return port.

[0042] The target rotational speed is greater than the preset rotational speed.

[0043] Optionally, the air conditioner further includes a second indoor heat exchanger, wherein the liquid outlet of the gas-liquid separator is connected to the refrigerant inlet of the second indoor heat exchanger, the refrigerant outlet of the second indoor heat exchanger is connected to the return port of the compressor via a pipeline, and the pipeline is connected to the outlet of the outlet pipe.

[0044] Optionally, the air outlet pipe is equipped with a third control valve, and the control method of the air conditioner further includes:

[0045] When the air conditioner is in cooling mode, the third control valve is opened.

[0046] Furthermore, in order to achieve the above objectives, this application also proposes an air conditioner, the air conditioner comprising:

[0047] compressor;

[0048] First indoor heat exchanger;

[0049] A gas-liquid separator, wherein the refrigerant outlet of the first indoor heat exchanger is connected to the gas-liquid inlet of the gas-liquid separator;

[0050] An oil separator, wherein the oil outlet of the oil separator is connected to the oil return port of the compressor via a first branch;

[0051] The second branch is connected in parallel with the first branch and is heat-exchange connected to the outlet pipe of the gas-liquid separator.

[0052] A flow direction control module is used to control the flow direction of the compressor oil flowing out of the oil outlet in the first branch and the second branch.

[0053] A control device, wherein the compressor and the flow control module are both connected to the control device, the control device includes: a memory, a processor, and an air conditioner control program stored in the memory and executable on the processor, wherein when the air conditioner control program is executed by the processor, it implements the steps of the air conditioner control method as described in any of the above.

[0054] Optionally, the flow direction control module includes a first control valve located on the first branch and a second control valve located on the second branch, both of which are connected to the control device.

[0055] Optionally, the air conditioner further includes a second indoor heat exchanger, wherein the liquid outlet of the gas-liquid separator is connected to the refrigerant inlet of the second indoor heat exchanger, the refrigerant outlet of the second indoor heat exchanger is connected to the return port of the compressor via a pipeline, and the pipeline is connected to the outlet of the outlet pipe.

[0056] Optionally, the air outlet pipe is equipped with a third control valve, which is connected to the control device.

[0057] Optionally, the air conditioner is a base station air conditioner, which includes an indoor unit, and the compressor, the oil separator, the first indoor heat exchanger, the gas-liquid separator, the second branch and the flow direction control module are all located in the indoor unit.

[0058] In addition, to achieve the above objectives, this application also proposes a computer-readable storage medium storing a control program for an air conditioner, which, when executed by a processor, implements the steps of the control method for the air conditioner as described in any of the preceding claims.

[0059] This invention proposes a control method for an air conditioner. In addition to connecting the oil outlet of the air conditioner's oil separator to the compressor's oil return port via a first branch, a second branch connected in parallel with the first branch and a control module for controlling the flow direction of the compressor oil in the first and second branches are also provided. The air conditioner further includes a gas-liquid separator to separate the refrigerant flowing out of the first indoor heat exchanger. The outlet pipe of the gas-liquid separator is connected to the second branch for heat exchange. Based on this, when the ambient temperature of the air conditioner is too high during cooling operation, the method controls the operation of the flow direction control module to ensure that the compressor oil flowing out of the oil separator exchanges heat with the outlet pipe via the second branch before flowing back to the compressor. Oil flows into the compressor. Since the first indoor heat exchanger is in an evaporating state during refrigeration operation, the low-temperature gaseous refrigerant obtained after heat exchange in the first indoor heat exchanger and separation by the gas-liquid separator can cool the compressor oil flowing out of the oil separator. The cooled compressor oil enters the compressor, which can reduce the compressor's operating temperature and effectively prevent the compressor from operating at excessively high temperatures. This reduces the compressor's discharge temperature, thereby effectively improving the compressor's operational reliability. At the same time, the reduced compressor operating temperature also helps to improve the air conditioner's cooling capacity under high-temperature conditions, thus increasing the air conditioner's cooling capacity. This achieves both improved compressor operational reliability and increased air conditioner cooling capacity. Attached Figure Description

[0060] Figure 1 This is a schematic diagram of the refrigerant system structure of an embodiment of the air conditioner of the present invention;

[0061] Figure 2 This is a schematic diagram of the hardware structure involved in the operation of an embodiment of the air conditioner of the present invention;

[0062] Figure 3 This is a flowchart illustrating an embodiment of the control method for an air conditioner according to the present invention;

[0063] Figure 4 This is a flowchart illustrating another embodiment of the control method for an air conditioner according to the present invention;

[0064] Figure 5 for Figure 4 Detailed flowchart of step S40;

[0065] Figure 6 This is a flowchart illustrating another embodiment of the control method for the air conditioner of the present invention.

[0066] The realization of the objective, functional features and advantages of the present invention will be further explained in conjunction with the embodiments and with reference to the accompanying drawings. Detailed Implementation

[0067] It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.

[0068] The main solution of this invention is as follows: a control method is proposed based on an air conditioner. The air conditioner includes a compressor, an oil separator, a first indoor heat exchanger, and a gas-liquid separator. The refrigerant outlet of the first indoor heat exchanger is connected to the gas-liquid inlet of the gas-liquid separator. The oil outlet of the oil separator is connected to the oil return port of the compressor through a first branch. The air conditioner also includes a flow direction control module and a second branch connected in parallel with the first branch. The second branch is heat-exchange connected to the outlet pipe of the gas-liquid separator. The flow direction control module is used to control the flow direction of the compressor oil flowing out of the oil outlet in the first branch and the second branch. Based on this air conditioner, the method includes: when the air conditioner is in cooling operation, obtaining the ambient temperature of the environment where the air conditioner is located; when the ambient temperature is greater than or equal to a preset temperature threshold, controlling the flow direction control module to operate so that the compressor oil flowing out of the oil outlet flows through the second branch and exchanges heat with the outlet pipe before entering the oil return port.

[0069] Because air conditioners often need to operate in high-temperature environments, and the compressor is usually located outdoors, the outdoor unit is in a heat-releasing state when the air conditioner is cooling. This can easily cause the compressor to operate at a high temperature. Excessive compressor operating temperature will not only reduce the cooling capacity of the air conditioner, but also easily damage the compressor and affect its reliability.

[0070] The present invention provides the above-mentioned solution, which aims to reduce the operating temperature of the compressor in order to improve the reliability of compressor operation and increase the cooling capacity of the air conditioner.

[0071] This invention provides an air conditioner. The air conditioner can be any type of air conditioner, such as a wall-mounted air conditioner, a cabinet air conditioner, a window air conditioner, a multi-split air conditioner, a ceiling-mounted air conditioner, or a portable air conditioner.

[0072] In this embodiment of the invention, reference is made to Figure 1 and Figure 2 The air conditioner includes a control device 100, a compressor 1, an oil separator 2, a first indoor heat exchanger 31, and a gas-liquid separator 4.

[0073] Specifically, the air conditioner includes a refrigerant circulation loop, which comprises a compressor 1, an oil separator 2, an outdoor heat exchanger 5, a throttling device 6, a first indoor heat exchanger 31, and a gas-liquid separator 4, connected in sequence. During cooling operation, the refrigerant discharged from the compressor 1 flows back to the compressor 1 after passing through the aforementioned components. The outdoor heat exchanger 5 is equipped with a corresponding outdoor fan 9, which drives outdoor air to flow through the outdoor heat exchanger 5 for heat exchange.

[0074] The gas-liquid separator 4 is provided with a gas-liquid inlet and a gas outlet. The refrigerant outlet of the first indoor heat exchanger 31 is connected to the gas-liquid inlet of the gas-liquid separator 4. The pipeline connected to the gas-liquid separator 4 is the gas outlet pipe 41 of the gas-liquid separator 4, and the inlet of the gas outlet pipe 41 is connected to the gas outlet. In this embodiment, the outlet of the gas outlet pipe 41 is connected to the return gas port of the compressor 1. The gaseous refrigerant separated by the gas-liquid separator 4 can replenish the compressor 1, increasing the proportion of gaseous refrigerant returning to the compressor 1. This prevents liquid slugging of the compressor 1 while reducing the operating load of the compressor 1, allowing the output refrigerant to carry more energy when the operating parameters of the compressor 1 are constant, thereby effectively improving the cooling capacity of the air conditioner. In other embodiments, the outlet of the gas outlet pipe 41 can also be connected to other locations in the refrigerant circulation loop, such as the gas replenishment port of the compressor 1.

[0075] The outlet pipe 41 of the gas-liquid separator 4 may be equipped with a third control valve 411. The third control valve 411 is connected to the control device 100, which can be used to control the operation of the third control valve 411 to regulate the flow rate of refrigerant through the outlet pipe 41. The third control valve 411 may be a check valve, a solenoid valve, or an electronic expansion valve, etc.

[0076] Compressor oil is a sealing medium used to lubricate the parts of compressor 1 and to seal the compression chamber. The inlet of oil separator 2 is connected to the discharge port of compressor 1, and the outlet of oil separator 2 is connected to the return port of compressor 1. The refrigerant discharged from compressor 1 enters oil separator 2 for separation of gaseous refrigerant and compressor oil. The separated gaseous refrigerant enters the condenser to continue the subsequent refrigerant circulation, while the separated compressor oil is discharged from the liquid outlet and flows back into compressor 1 from the return port of compressor 1.

[0077] The oil outlet of the oil separator 2 is connected to the oil return port of the compressor 1 via a first branch 21. The air conditioner also includes a flow direction control module 8 and a second branch 22 connected in parallel with the first branch 21. The flow direction control module 8 is connected to the control device 100. The second branch 22 is heat-exchange connected to the outlet pipe 41 of the gas-liquid separator 4. The flow direction control module 8 is used to control the flow direction of the compressor oil flowing out of the oil outlet in the first branch 21 and the second branch 22. The second branch 22 and the outlet pipe 41 can be in direct contact or connected through a heat transfer structure to achieve heat exchange between them.

[0078] In this embodiment, the flow control module 8 includes a first control valve 81 located on the first branch 21 and a second control valve 82 located on the second branch 22. Both the first control valve 81 and the second control valve 82 are connected to the control device 100, which can be used to control the operation of the first control valve 81 and the second control valve 82. In this embodiment, both the first control valve 81 and the second control valve 82 are electronic expansion valves. In other embodiments, one of the first control valve 81 and the second control valve 82 may be an electronic expansion valve, or one of the first control valve 81 and the second control valve 82 may be a solenoid valve or a check valve, etc.; or, both the first control valve 81 and the second control valve 82 may be solenoid valves, etc.

[0079] In other embodiments, the flow control module 8 may also include a three-way valve. The first port of the three-way valve is connected to the first branch 21, the second port is connected to the second branch 22, and the third port is connected to the oil outlet of the oil separator 2. The three-way valve may have a first operating position and a second operating position. When the three-way valve is in the first operating position, all the compressor oil flowing out of the oil outlet flows back to the compressor 1 through the second branch 22. When the three-way valve is in the second operating position, all the compressor oil flowing out of the oil outlet flows back to the compressor 1 through the first branch 21.

[0080] Furthermore, in this embodiment, referring to Figure 1 The air conditioner also includes a second indoor heat exchanger 32, and a gas-liquid separator 4 is provided with a liquid outlet. The liquid outlet is connected to the refrigerant inlet of the second indoor heat exchanger 32 through a first pipeline, and the refrigerant outlet of the second indoor heat exchanger 32 is connected to the return port of the compressor 1 through a second pipeline. The second pipeline is connected to the outlet of the outlet pipe 41. When the air conditioner is in cooling operation, the first indoor heat exchanger 31 and the second indoor heat exchanger 32 are in an evaporation state. The refrigerant entering the room first evaporates in the first indoor heat exchanger 31 to form a gas-liquid mixture. The gas-liquid mixture enters the gas-liquid separator 4 for separation. The separated liquid refrigerant flows into the second indoor heat exchanger 32 for further evaporation, and the separated gaseous refrigerant flows from the first pipeline into the second pipeline and then back to the compressor 1. The separation function of the gas-liquid separator 4 can increase the proportion of liquid refrigerant flowing into the second indoor heat exchanger 32 and reduce the proportion of gaseous refrigerant. The reduction of gaseous refrigerant is conducive to improving the evaporation efficiency of liquid refrigerant in the second indoor heat exchanger 32, so that more refrigerant evaporates in the second indoor heat exchanger 32 and releases cooling capacity. This increases the cooling capacity output of the second indoor heat exchanger 32 when the operating conditions of other components are constant, thereby increasing the overall cooling capacity output of the indoor heat exchanger.

[0081] Furthermore, in this embodiment, referring to Figure 1The air conditioner is designed to allow switching between cooling and heating modes. The refrigerant circulation loop may also include a four-way valve 7, which is connected to the control device 100. Two ports of the four-way valve 7 are connected to the exhaust port and return port of the compressor 1, respectively, and the other two ports are connected to the indoor heat exchanger and the outdoor heat exchanger 5, respectively. An oil separator 2 is located between the four-way valve 7 and the exhaust port of the compressor 1. The four-way valve 7 has a first valve position and a second valve position. When the four-way valve 7 is in the first valve position, the air conditioner operates in cooling mode; when the four-way valve 7 is in the second valve position, the air conditioner operates in heating mode. In other embodiments, the air conditioner may also be a cooling-only type, in which case the four-way valve 7 is not included in the refrigerant circulation loop.

[0082] Furthermore, in this embodiment, the air conditioner is a base station air conditioner, which includes an indoor unit. The compressor 1, the oil separator 2, the first indoor heat exchanger 31, the gas-liquid separator 4, the second branch 22, and the flow direction control module 8 are all located in the indoor unit. The compressor 1 of the base station air conditioner is located indoors, which facilitates a more organized outdoor unit air duct. Under the same noise level, the outdoor fan can operate at a higher speed, reducing system pressure and improving the reliability of the compressor 1 under high-temperature conditions.

[0083] Furthermore, in this embodiment, referring to Figure 2 The air conditioner also includes a first temperature detection module 01, which is used to detect the ambient temperature of the environment where the air conditioner is located. The ambient temperature may include the indoor ambient temperature and / or the outdoor ambient temperature. In this embodiment, the first temperature detection module 01 is located on the air conditioner. For example, when the first temperature detection module 01 is used to detect the outdoor ambient temperature, it may be located on the casing of the outdoor unit; when it is used to detect the indoor ambient temperature, it may be located at the return air vent of the indoor unit. In other embodiments, the first temperature detection module 01 may also be located in the external area of ​​the air conditioner in the environment where the air conditioner is located. The first temperature detection module 01 is connected to the control device 100, and the control device 100 can acquire the data detected by the first temperature detection module 01.

[0084] Furthermore, in this embodiment, referring to Figure 2 The air conditioner also includes a second temperature detection module 02, which is used to detect the oil return temperature of the compressor 1. The second temperature detection module 02 is located at the confluence of the first branch 21 and the second branch 22. In this embodiment, the second temperature detection module 02 is located at the oil return port of the compressor 1. In other embodiments, the second temperature detection module 02 may also be located at the oil outlet of the oil separator 2. The second temperature detection module 02 is connected to the control device 100, and the control device 100 can acquire the data detected by the second temperature detection module 02.

[0085] Furthermore, in this embodiment, referring to Figure 2 The air conditioner also includes a temperature sensor 03, which is used to detect the exhaust temperature of the compressor 1. The temperature sensor 03 is connected to the control device 100, which can be used to acquire the data detected by the temperature sensor 03. The temperature sensor 03 is located at the exhaust port of the compressor 1.

[0086] In this embodiment of the invention, reference is made to Figure 2 The control device 1001 of the air conditioner includes: a processor 1001 (e.g., CPU), a memory 1002, a timer 1003, etc. The components in the control device 1001 are connected via a communication bus. The memory 1002 can be a high-speed RAM or a stable, non-volatile memory, such as a disk drive. Optionally, the memory 1002 can also be a storage device independent of the aforementioned processor 1001.

[0087] Those skilled in the art will understand that Figure 2 The device structure shown does not constitute a limitation on the device and may include more or fewer components than shown, or combine certain components, or have different component arrangements.

[0088] like Figure 2 As shown, the memory 1002, which is a computer-readable storage medium, may include a control program for an air conditioner. Figure 2 In the device shown, the processor 1001 can be used to call the control program of the air conditioner stored in the memory 1002 and execute the relevant steps of the control method of the air conditioner in the following embodiments.

[0089] This invention also provides a control method for an air conditioner, applied to the aforementioned air conditioner.

[0090] Reference Figure 3 This application proposes an embodiment of a control method for an air conditioner. In this embodiment, the air conditioner includes a compressor, an oil separator, a first indoor heat exchanger, and a gas-liquid separator. The refrigerant outlet of the first indoor heat exchanger is connected to the gas-liquid inlet of the gas-liquid separator. The oil outlet of the oil separator is connected to the oil return port of the compressor via a first branch. The air conditioner further includes a flow direction control module and a second branch connected in parallel with the first branch. The second branch is heat-exchange connected to the outlet pipe of the gas-liquid separator. The flow direction control module is used to control the flow direction of the compressor oil flowing out of the oil outlet in the first branch and the second branch. The control method of the air conditioner includes:

[0091] Step S10: When the air conditioner is in cooling operation, obtain the ambient temperature of the environment where the air conditioner is located;

[0092] When the air conditioner is in cooling mode, both the first indoor heat exchanger and the second indoor heat exchanger are in an evaporation state.

[0093] In this embodiment, the ambient temperature includes the outdoor ambient temperature. In other embodiments, the ambient temperature may also include the indoor ambient temperature, or it may include both the outdoor and indoor ambient temperatures. Specifically, when the air conditioner starts cooling, the data detected in real time by the first temperature detection module can be used as the ambient temperature here.

[0094] Step S20: When the ambient temperature is greater than or equal to a preset temperature threshold, control the flow direction control module to operate so that the compressor oil flowing out of the oil outlet flows through the second branch and exchanges heat with the gas outlet pipe before entering the oil return port.

[0095] The preset temperature threshold is specifically a critical value used to distinguish whether the compressor is at risk of overheating under current operating conditions. In this embodiment, the preset temperature threshold is 50°C. In other embodiments, the preset temperature threshold may also be 55°C, 40°C, or 38°C, etc.

[0096] When the ambient temperature is greater than or equal to the preset temperature threshold, it indicates that the compressor of the air conditioner is at risk of overheating under the current operating conditions. At this time, through the operation regulation of the flow control module, the compressor oil that needs to be returned to the compressor by the oil separator can enter the second branch to exchange heat with the outlet pipe. Since the first indoor heat exchanger is in the evaporation state, the gaseous refrigerant obtained after heat exchange in the first indoor heat exchanger is low-temperature gaseous refrigerant. The low-temperature gaseous refrigerant exchanges heat with the compressor oil in the second branch in the outlet pipe. After absorbing the cold energy in the low-temperature gaseous refrigerant, the compressor oil flows into the compressor from the oil return port of the compressor. When the compressor oil participates in the operation inside the compressor, it can reduce the overall operating temperature of the compressor.

[0097] In this embodiment, the flow control module includes a first control valve located on the first branch and a second control valve located on the second branch. The step of controlling the flow control module to operate so that the compressor oil flowing from the oil outlet flows through the second branch and exchanges heat with the outlet pipe before entering the oil return port includes: controlling the first control valve to close and controlling the second control valve to open. Based on this, all the compressor oil flowing out of the oil separator is cooled in the second branch before entering the compressor. In other embodiments, both the first and second control valves can be controlled to open, so that part of the compressor oil flowing out of the oil separator is cooled in the second branch before entering the compressor, and the other part directly enters the compressor through the first branch.

[0098] In other embodiments, the flow direction control module may also include the aforementioned third-way valve. Based on this, the step of controlling the operation of the flow direction control module so that the compressor oil flowing out of the oil outlet flows through the second branch and exchanges heat with the outlet pipe before entering the return oil port includes: controlling the three-way valve to operate in the aforementioned first operating position.

[0099] This invention proposes a control method for an air conditioner. The oil separator of this air conditioner, in addition to being connected to the compressor oil return port via a first branch, also has a second branch connected in parallel with the first branch and a control module for controlling the flow direction of the compressor oil in the first and second branches. The air conditioner also includes a gas-liquid separator to separate the refrigerant flowing out of the first indoor heat exchanger. The outlet pipe of the gas-liquid separator is connected to the second branch for heat exchange. Based on this, when the ambient temperature of the air conditioner is too high during cooling operation, the method controls the operation of the flow direction control module to ensure that the compressor oil flowing out of the oil separator exchanges heat with the outlet pipe via the second branch before passing through... The oil flows into the compressor through the return port. Since the first indoor heat exchanger is in an evaporating state during refrigeration operation, the low-temperature gaseous refrigerant obtained after heat exchange in the first indoor heat exchanger and separation by the gas-liquid separator can cool the compressor oil flowing out of the oil separator. The cooled compressor oil enters the compressor, which can reduce the compressor's operating temperature and effectively prevent the compressor from operating at excessively high temperatures. This reduces the compressor's discharge temperature, thereby effectively improving the compressor's operational reliability. At the same time, the reduced compressor operating temperature also helps to improve the air conditioner's cooling capacity under high-temperature conditions, thus increasing the air conditioner's cooling capacity. This achieves both improved compressor operational reliability and increased air conditioner cooling capacity.

[0100] Furthermore, in the above embodiment, after step S10, the method further includes: when the ambient temperature is less than the preset temperature threshold, controlling the flow direction control module to operate, so that the compressor flowing out of the oil outlet flows through the first branch and enters the oil return port.

[0101] When the ambient temperature is lower than the preset temperature threshold, it indicates that the compressor of the air conditioner does not have the risk of overheating under the current operating conditions. At this time, through the operation regulation of the flow control module, the compressor oil flowing out of the oil separator flows directly back to the compressor through the first branch, so that the compressor can operate within the normal temperature range.

[0102] In this embodiment, the flow direction control module includes a first control valve located on the first branch and a second control valve located on the second branch. The step of controlling the flow direction control module to ensure that the compressor oil flowing from the oil outlet flows through the first branch and into the oil return port includes: controlling the first control valve to open and controlling the second control valve to close. Based on this, all the compressor oil flowing out of the oil separator is cooled in the first branch before entering the compressor. In other embodiments, both the first and second control valves can be opened, so that part of the compressor oil flowing out of the oil separator is cooled in the second branch before entering the compressor, while the other part directly enters the compressor through the first branch.

[0103] In other embodiments, the flow direction control module may also include the aforementioned third-way valve. Based on this, the step of controlling the operation of the flow direction control module to make the compressor flowing out of the oil outlet flow through the first branch and enter the oil return port includes: controlling the three-way valve to operate in the aforementioned second operating position.

[0104] Furthermore, in the above embodiment, the air outlet pipe is provided with a third control valve, and the control method of the air conditioner further includes: when the air conditioner is in cooling operation, controlling the third control valve to open.

[0105] Specifically, in this embodiment, when the air conditioner is in cooling operation, if the ambient temperature is greater than or equal to a preset temperature threshold, the third control valve is controlled to open, the first control valve is controlled to close, and the second control valve is controlled to open; if the ambient temperature is less than the preset temperature threshold, the third control valve is controlled to open, the first control valve is controlled to open, and the second control valve is controlled to close.

[0106] Opening the third control valve here helps to increase the proportion of gaseous refrigerant returning to the compressor, thereby avoiding liquid slugging on the compressor and reducing the compressor's operating load. This increases the compressor's output capacity during the air conditioner's cooling process, thus increasing the air conditioner's cooling output.

[0107] In other embodiments, when the air conditioner is in cooling operation, when the ambient temperature is greater than or equal to a preset temperature threshold, the third control valve can be controlled to open, the first control valve can be controlled to close, and the second control valve can be controlled to open; when the ambient temperature is greater than or equal to the preset temperature threshold, the third control valve can be controlled to close, the first control valve can be controlled to close, and the second control valve can be controlled to open.

[0108] Furthermore, based on the above embodiments, another embodiment of the control method for the air conditioner of this application is proposed. In this embodiment, reference is made to... Figure 4 After the steps of controlling the first control valve to close and controlling the second control valve to open, the method further includes:

[0109] Step S30: Obtain the first oil return temperature of the compressor;

[0110] The first return oil temperature is obtained by acquiring real-time data from the second temperature detection module.

[0111] Specifically, step S30 can be executed when the duration of the first control valve being closed and the second control valve being open is greater than or equal to a preset duration.

[0112] Step S40: Determine the first opening control parameter of the first control valve and the second opening control parameter of the second control valve based on the first return oil temperature;

[0113] Here, the first opening control parameter and the second opening control parameter are parameters used to make the compressor's oil return temperature reach the target temperature range mentioned later.

[0114] The first opening control parameters include the opening and closing control parameters of the first control valve (such as opening or closing the first control valve) and / or the opening adjustment parameters (such as the opening adjustment direction (such as increasing or decreasing the opening), the opening adjustment range, and / or the opening adjustment rate).

[0115] Among them, the opening degree of the first control valve corresponding to the first opening degree control parameter is negatively correlated with the first return oil temperature; the opening degree of the second control valve corresponding to the second opening degree control parameter is positively correlated with the first return oil temperature.

[0116] Different first return oil temperatures correspond to different first and second opening control parameters. Specifically, the correspondence between the first return oil temperature and the first and second opening control parameters can be established in advance or obtained based on the actual operating conditions of the air conditioner. This correspondence can take the form of a calculation formula, mapping relationship, etc. Based on this correspondence, the first and second opening control parameters corresponding to the current first return oil temperature can be determined.

[0117] Specifically, the first and second opening control parameters can be determined based on the quantitative relationship between the first return oil temperature and the target temperature range (such as their magnitude, difference, or ratio with the critical value of the target temperature range). Alternatively, at least two temperature ranges can be pre-defined, with one of them being the target temperature range. The first and second opening control parameters can then be determined based on the temperature range in which the first return oil temperature falls, and so on.

[0118] Step S50: Control the first control valve to operate with the first opening control parameter, and control the second control valve to operate with the second opening control parameter, so that the temperature of the compressor oil return is within the target temperature range.

[0119] The target temperature range is specifically the temperature range required for the compressor to return oil reliably during operation. In this embodiment, the target temperature range has a minimum and a maximum value. In other embodiments, the target temperature range may also be the set of all temperatures less than or equal to the preset oil return temperature.

[0120] Specifically, while controlling the first control valve according to the first opening control parameter, the second control valve is controlled according to the second opening control parameter.

[0121] Furthermore, after step S50, the process can return to step S30 at set intervals, thereby continuously regulating the first and second control valves based on the compressor's oil return temperature during the air conditioner's cooling process, ensuring that the compressor oil temperature can be maintained within the target temperature range.

[0122] In this embodiment, after cooling the compressor oil using the cooling capacity of the gaseous refrigerant in the outlet pipe by opening the second control valve and closing the first control valve, the opening degree of the first control valve and the second control valve are further adjusted according to the return oil temperature of the compressor. Thus, the flow rate of the compressor oil is regulated by the cooperation of the first control valve and the second control valve, so that the temperature of the compressor oil flowing into the compressor after mixing from the first branch and the second branch is within the target temperature range. This ensures that the compressor operating temperature is neither too high nor too low, effectively improving the operational reliability of the compressor during refrigeration operation and improving the cooling capacity of the air conditioner.

[0123] Furthermore, after the steps of controlling the first control valve to close and the second control valve to open, the method further includes: obtaining the continuous operating time of the compressor after startup; and when the continuous operating time is greater than or equal to a preset time, performing the step of obtaining the first oil return temperature of the compressor. A continuous operating time of the compressor after startup greater than or equal to the preset time indicates that the compressor has now reached the target frequency required for cooling under the current operating conditions. At this point, adjusting the opening of the first and second control valves based on the compressor's oil return temperature helps improve the accuracy of the control of the first and second control valves, ensuring that the compressor's oil return temperature can accurately reach the target temperature range.

[0124] Furthermore, in this embodiment, referring to Figure 5 Step S40 includes:

[0125] Step S41: When the first return oil temperature is less than the minimum value of the target temperature range, determining the first opening control parameter includes opening the first control valve, and determining the second opening control parameter includes closing the second control valve.

[0126] If the first return oil temperature is lower than the minimum value of the target temperature range, it indicates that the compressor's operating temperature is too low. At this time, the compressor is under heavy load and has low cooling capacity. In this case, the first control valve is opened and the second control valve is closed, so that all the compressor oil flowing out of the oil separator flows back to the compressor through the first branch and is no longer cooled through the second branch. This ensures that the temperature of the compressor oil is not too low and remains within the target temperature range, thus ensuring the normal operation of the compressor and effectively balancing compressor reliability and air conditioning cooling capacity.

[0127] In addition to opening the first control valve, the first opening control parameter may also include reducing the opening of the first control valve to reduce the backflow of compressor oil at excessively low temperatures into the compressor, ensuring that the compressor does not operate at excessively low temperatures, thereby further improving the compressor's reliability and the air conditioning's cooling capacity.

[0128] In other embodiments, when the first return oil temperature is less than the minimum value of the target temperature range, the first opening control parameter may be determined to include increasing the opening of the first control valve, and the second opening control parameter may be determined to include decreasing the opening of the second control valve.

[0129] Step S42: When the first return oil temperature is greater than the maximum value of the target temperature range, determine the temperature difference between the first return oil temperature and the maximum value, and determine the first opening control parameter and the second opening control parameter based on the temperature difference.

[0130] The temperature difference value is specifically calculated by subtracting the maximum value of the target temperature range from the first return oil temperature. Different temperature difference values ​​correspond to different first opening control parameters and second opening control parameters.

[0131] In this embodiment, the first opening control parameter further includes a first target opening of the first control valve, and the second opening control parameter includes a second target opening of the second control valve. The step of determining the first opening control parameter and the second opening control parameter based on the temperature difference value includes: determining the first target opening and the second target opening based on the temperature difference value; wherein, the first target opening is negatively correlated with the temperature difference value, and the second target opening is positively correlated with the temperature difference value.

[0132] Specifically, the temperature difference value can be pre-divided into at least two numerical intervals, such as (0, 5], (5, 10], (10, 15], (15, +∞), etc. Each numerical interval corresponds to a first preset opening degree of a first control valve and a second preset opening degree of a second control valve. Within the at least two numerical intervals, a target interval in which the current temperature difference value lies is determined. The first preset opening degree associated with the target interval is taken as the first target opening degree, and the second preset opening degree associated with the target interval is taken as the second target opening degree.

[0133] In other embodiments, after determining the temperature difference value, the first opening control parameter may be determined when the temperature difference value is greater than a set threshold, including closing the first control valve, and the second opening control parameter may be determined when the temperature difference value is less than or equal to a set threshold, including opening the first control valve, and the second opening control parameter may be determined when the temperature difference value is less than or equal to a set threshold, including increasing the opening of the second control valve.

[0134] In this embodiment, steps S41 and S42 ensure that the oil return temperature of the compressor is neither too high nor too low, reaching the target temperature range, thus ensuring reliable operation of the compressor while improving its cooling capacity.

[0135] Furthermore, prior to step S40, the coil temperature of the first indoor heat exchanger and / or the opening degree of the third control valve can be obtained. Based on the coil temperature of the first indoor heat exchanger and / or the opening degree of the third control valve, a target correspondence between the first oil return temperature and the first and second opening degree control parameters is obtained. Different coil temperatures and / or the opening degree of the third control valve correspond to different target correspondences. The first and second opening degree control parameters are determined based on this target correspondence. For example, when the first oil return temperature is greater than the maximum value of the target temperature range, the target correspondence between the temperature difference value and the first and second target opening degrees is obtained based on the coil temperature and / or the opening degree of the third control valve. The first and second target opening degrees corresponding to the current temperature difference value are then determined based on this target correspondence. This method helps improve the accuracy of the regulation of the first and second control valves, ensuring that the compressor's oil return temperature can accurately reach the target temperature range, further improving the compressor's operational reliability and the air conditioner's cooling capacity.

[0136] Furthermore, based on any of the above embodiments, another embodiment of the control method for the air conditioner of this application is proposed. In this embodiment, reference is made to... Figure 6 After step S20, the following steps are also included:

[0137] Step S60: Obtain the second oil return temperature and the first discharge temperature of the compressor;

[0138] The second return oil temperature is obtained by acquiring real-time data from the second temperature detection module.

[0139] The first exhaust temperature is obtained by acquiring the real-time data detected by the temperature sensor located at the compressor exhaust port.

[0140] Step S70: When the second return oil temperature is greater than the first preset temperature and the first exhaust temperature is greater than the second preset temperature, control the compressor to operate at a reduced frequency.

[0141] The first preset temperature and the second preset temperature are specifically critical temperature values ​​used to distinguish whether there is a risk of the compressor failing to operate reliably. If the oil return temperature is greater than the first preset temperature and the exhaust temperature is greater than the second preset temperature, it indicates that the compressor is at risk of failing to operate reliably; if the oil return temperature is less than or equal to the first preset temperature and / or the exhaust temperature is less than or equal to the second preset temperature, it indicates that the compressor is not at risk of failing to operate reliably.

[0142] Wherein, the first preset temperature is less than the maximum allowable oil temperature of the compressor, and the second preset temperature is less than the maximum allowable discharge temperature of the compressor. Specifically, the first preset temperature is determined based on the maximum oil temperature and the first preset value, for example, the difference between the maximum oil temperature and the first preset value is used as the first preset temperature; the second preset temperature is determined based on the maximum discharge temperature and the second preset value, for example, the difference between the maximum discharge temperature and the second preset value is used as the second preset temperature.

[0143] Specifically, the compressor's frequency reduction rate and / or frequency reduction amplitude can be a preset fixed value or a value determined according to the actual operating conditions of the air conditioner.

[0144] In this embodiment, when both the oil return temperature and the exhaust temperature of the compressor are too high, the compressor frequency is limited to ensure that the compressor can quickly reduce its operating temperature, which is beneficial to improving the reliability of compressor operation.

[0145] It should be noted that when step S20 includes steps S30 to S50 as described above, obtaining the second return oil temperature of the compressor in step S30 and step S60 can be combined into one step. After step S60, in addition to executing step S70, steps S40 and S50 are also executed. Specifically, steps S40 and S50 can be executed first and then step S70 can be executed, or steps S70 can be executed first and then steps S40 and S50 can be executed, or steps S40, S70 and S50 can be executed sequentially.

[0146] Furthermore, after step S70, the system can return to step S60 at set intervals (e.g., 10s, 20s, etc.) to continuously regulate the operation of the compressor and / or the first control valve and the second control valve based on the return gas temperature and the exhaust gas temperature.

[0147] Furthermore, when the second return oil temperature is less than or equal to the first preset temperature, or when the first exhaust temperature is less than or equal to the second preset temperature, the compressor can be controlled to maintain the current frequency of operation.

[0148] Furthermore, in this embodiment, the step of controlling the compressor to operate at a reduced frequency includes: controlling the compressor to operate at a reduced frequency at a first target rate, wherein the first target rate is greater than a preset rate.

[0149] The preset rate can be a pre-set threshold value used to distinguish between fast and slow compressor frequency adjustment rates. A compressor frequency adjustment rate greater than the preset rate indicates that the compressor frequency is adjusted rapidly, while a compressor frequency adjustment rate less than or equal to the preset rate indicates that the compressor frequency is adjusted slowly.

[0150] The first target rate can be a preset fixed rate, or it can be a frequency determined according to the actual operating conditions of the air conditioner. For example, it can be determined based on the temperature difference between the indoor ambient temperature and the set temperature within a range greater than the preset rate.

[0151] In this embodiment, when both the return oil temperature and the discharge temperature of the compressor are too high, the compressor reduces its frequency at a higher rate, thereby further improving the efficiency of reducing the compressor's operating temperature and further improving the reliability of the compressor operation.

[0152] In other embodiments, the compressor may be controlled to reduce its frequency at a rate less than a preset rate.

[0153] Furthermore, in this embodiment, after step S70, the method may further include: obtaining the third oil return temperature and the second exhaust temperature of the compressor; when the third oil return temperature is less than the third preset temperature and the second exhaust temperature is less than the fourth preset temperature, controlling the compressor to operate at a second target rate; wherein, the third preset temperature is less than the first preset temperature, the fourth preset temperature is less than the second preset temperature, and the second target rate is less than or equal to the preset rate.

[0154] The third oil return temperature and the second exhaust temperature are obtained by acquiring the current detection data from the second temperature detection module and the temperature sensor. These temperatures are monitored in real time during the compressor's frequency reduction process.

[0155] The preset rate mentioned here refers to the same concept as the preset rate mentioned above, and will not be repeated here.

[0156] The second target rate can be a preset fixed rate, or it can be a frequency determined according to the actual operating conditions of the air conditioner. For example, it can be determined based on the temperature difference between the indoor ambient temperature and the set temperature within a range that is less than the preset rate.

[0157] The third and fourth preset temperatures are specifically the critical temperatures used to distinguish whether the compressor has reached a stable and reliable operating state.

[0158] When the third return oil temperature is lower than the third preset temperature and the second exhaust temperature is lower than the fourth preset temperature, it indicates that the compressor has reached a stable and reliable operating state. At this time, the frequency is increased at a slower rate to improve the cooling capacity of the air conditioner while ensuring that the compressor will not fail to operate reliably.

[0159] Furthermore, in this embodiment, after step S60, the method further includes: when the second oil return temperature is greater than the fifth preset temperature and the first exhaust temperature is greater than the sixth preset temperature, controlling the compressor to stop; when the second oil return temperature is less than or equal to the fifth preset temperature, and / or the first exhaust temperature is less than or equal to the sixth preset temperature, executing the step of controlling the compressor to operate at a reduced frequency at a first target rate when the second oil return temperature is greater than the first preset temperature and the first exhaust temperature is greater than the second preset temperature;

[0160] The fifth preset temperature is greater than the first preset temperature, and the sixth preset temperature is greater than the second preset temperature.

[0161] The fifth and sixth preset temperatures are specifically critical temperature values ​​used to distinguish the level of risk that the compressor may not be able to operate reliably.

[0162] Specifically, the fifth preset temperature is less than the maximum allowable oil temperature of the compressor, and the sixth preset temperature is less than the maximum allowable discharge temperature of the compressor. Specifically, the first preset temperature is determined based on the maximum oil temperature and a third preset value; for example, the difference between the maximum oil temperature and the third preset value is used as the fifth preset temperature, where the third preset value is less than the first preset value. The sixth preset temperature is determined based on the maximum discharge temperature and a fourth preset value; for example, the difference between the maximum discharge temperature and the fourth preset value is used as the second preset temperature, where the fourth preset value is less than the second preset value.

[0163] If the second oil return temperature is greater than the fifth preset temperature and the first discharge temperature is greater than the sixth preset temperature, it indicates a high risk that the compressor may not operate reliably. In this case, the compressor should be stopped to ensure that it is not damaged and to extend its service life. If the oil return temperature is less than or equal to the first preset temperature and / or the discharge temperature is less than or equal to the second preset temperature, it indicates a low risk that the compressor may not operate reliably. In this case, the risk of compressor damage is low. The compressor frequency should be adjusted according to the oil temperature and discharge temperature to ensure that the air conditioner continuously outputs cooling capacity while effectively improving the reliability of the compressor operation.

[0164] Furthermore, based on any of the above embodiments, after step S10, the method further includes:

[0165] When the ambient temperature is greater than or equal to a preset temperature threshold, the outdoor fan of the air conditioner is controlled to run at a target speed, and the flow direction control module is executed to make the compressor oil flowing out of the oil outlet flow through the second branch and exchange heat with the outlet pipe before entering the oil return port.

[0166] The target rotational speed is greater than the preset rotational speed.

[0167] The preset speed is a critical value used to distinguish between fast and slow outdoor fan operation. An outdoor fan speed greater than the preset speed indicates high-speed operation; an outdoor fan speed less than the preset speed indicates slow operation. For example, the preset speed can be 50%, 60%, or 80% of the maximum allowable operating speed of the outdoor fan.

[0168] In this embodiment, the target speed is the maximum speed at which the outdoor fan is allowed to operate. In other embodiments, the target speed may also be a speed value between a preset speed and the maximum speed. For example, if the preset speed is 80% of the maximum speed, the target speed may be 90% or 95% of the maximum speed, and so on.

[0169] In this embodiment, by cooling the compressor oil through the second branch while controlling the outdoor fan to run at a higher speed, it is beneficial to quickly reduce the pressure on the high-pressure side of the refrigerant system, thereby further improving the reliability of compressor operation and even the operation of the entire system.

[0170] Furthermore, the air conditioner may also have a fourth control valve installed in the pipeline between the liquid outlet of the gas-liquid separator and the refrigerant inlet of the second indoor heat exchanger. Based on this, when the air conditioner is in cooling operation, the first temperature of the indoor environment is obtained; the operating parameters of the fourth control valve of the air conditioner are determined according to the first temperature; and the fourth control valve is controlled to operate with the operating parameters so that the cooling capacity output by the air conditioner matches the cooling capacity currently required by the indoor environment.

[0171] The first temperature is obtained by acquiring data from the first temperature detection module in real time. During the cooling operation of the air conditioner, the first temperature of the indoor environment can be acquired at set intervals (such as 5s, 10s, or 15s).

[0172] The operating parameters of the fourth control valve are those related to the regulation of the cooling capacity output of the air conditioner. Specifically, the operating parameters of the fourth control valve are used to regulate the amount of refrigerant flowing into the second indoor heat exchanger from the outlet of the gas-liquid separator. The operating parameters of the fourth control valve specifically include its opening and closing control parameters (such as opening or closing the control valve) and / or opening degree control parameters (such as target opening degree or opening degree adjustment parameters).

[0173] Different first temperatures correspond to different operating parameters. Specifically, different first temperatures correspond to different opening and closing control parameters for the fourth control valve. Different first temperatures also correspond to different opening control parameters for the fourth control valve. The correspondence between the first temperature and operating parameters can be preset or determined based on the air conditioner's operating conditions for the year. Based on this correspondence, the operating parameters of the fourth control valve corresponding to the first temperature can be determined.

[0174] The current cooling capacity required by the indoor environment is specifically characterized by the indoor ambient temperature, and the current cooling capacity required by the indoor environment is positively correlated with the indoor ambient temperature.

[0175] It should be noted that when the air conditioner is equipped with the aforementioned third control valve, the third control valve is opened while the fourth control valve is being controlled to operate with the aforementioned operating parameters.

[0176] When the compressor is a fixed-frequency compressor, controlling the fourth control valve to operate with the specified operating parameters further includes: when the first temperature is less than or equal to the set temperature, controlling the fixed-frequency compressor to remain on. When the compressor is a variable-frequency compressor, when controlling the fourth control valve to operate with the specified operating parameters, when the first temperature is less than or equal to the set temperature, the compressor can be controlled to operate at a pre-set fixed frequency, or it can operate at a target frequency determined based on the current indoor temperature. Based on this, it can effectively avoid large fluctuations in indoor temperature caused by the compressor (especially a fixed-frequency compressor) shutting down after reaching the set temperature, thus improving user comfort.

[0177] During the cooling operation of the air conditioner, the operation of the fourth control valve is adjusted according to the indoor ambient temperature. Different operating states of the fourth control valve can result in different amounts of refrigerant flowing from the gas-liquid separator into the second indoor heat exchanger, thereby regulating the cooling capacity output by the air conditioner in the indoor heat exchanger. During this process, the cooling capacity output by the indoor heat exchanger is no longer fixed, but can be adjusted by the fourth control valve according to the indoor ambient temperature, thus ensuring that the output cooling capacity matches the indoor environmental demand. This ensures that the cooling capacity output by the air conditioner meets the indoor environmental demand during the cooling operation, improving user comfort during the air conditioner's cooling process.

[0178] Specifically, when the first temperature is greater than the set temperature of the air conditioner, the operating parameters are determined to include the opening of the fourth control valve; when the first temperature is less than or equal to the set temperature, the operating parameters are determined to include the closing of the fourth control valve.

[0179] When the first temperature is higher than the set temperature, it indicates that the indoor environment requires a large amount of cooling. At this time, the fourth control valve is opened, allowing the liquid refrigerant in the gas-liquid separator to flow into the second indoor heat exchanger for heat exchange. The first and second indoor heat exchangers evaporate simultaneously to release cooling capacity with a larger heat exchange area. There is no gaseous refrigerant flowing into the second indoor heat exchanger, which helps to improve the refrigerant evaporation efficiency. This increases the cooling capacity released by the indoor heat exchangers while maintaining a fixed compressor displacement and a fixed total heat exchange area. This helps to shorten the cooling time of the air conditioner, allowing the indoor environment to quickly reach the set temperature and meet the comfort needs of indoor users.

[0180] Furthermore, when the first temperature is less than or equal to the set temperature, it indicates that the indoor environment has reached the user's comfortable temperature and the required cooling capacity is relatively small. At this time, the fourth control valve is closed. The refrigerant flowing into the room passes through the first indoor heat exchanger for heat exchange and is separated by the gas-liquid separator. It no longer flows into the second indoor heat exchanger for heat exchange. The separated gaseous refrigerant flows into the second pipeline through the third pipeline and then back to the compressor. The indoor heat exchanger exchanges heat with a smaller heat exchange area, which can avoid the compressor from stopping due to excessively low indoor temperature and avoid a significant rise in indoor temperature caused by compressor shutdown. This ensures that the compressor maintains stable operation while the indoor environment meets the user's comfort requirements.

[0181] In this embodiment, the fourth control valve can operate at a preset fixed opening degree when it is opened. In other embodiments, the target opening degree of the fourth control valve can also be determined based on the first temperature. The operating parameters of the fourth control valve include the target opening degree, which is positively correlated with the first temperature. Specifically, the temperature difference between the first temperature and the set temperature can be determined, and the target opening degree is positively correlated with the temperature difference value. Specifically, the target opening degree can be calculated from the first temperature or the temperature difference value; alternatively, it can be obtained by querying a mapping relationship using the first temperature or the temperature difference value. Further, when the first temperature is greater than the set temperature of the air conditioner, the target opening degree of the fourth control valve can be determined based on the first temperature, and the operating parameters determined include the fourth control valve opening at the target opening degree.

[0182] Furthermore, when the first temperature is less than or equal to the set temperature, the step of controlling the fourth control valve to operate with the operating parameters is performed simultaneously or afterward, and further includes: acquiring a second temperature of the indoor environment; determining a target opening degree of the third control valve based on the second temperature; and controlling the third control valve to open with the target opening degree so that the difference between the indoor environment temperature and the set temperature is less than a set value.

[0183] The target opening degree is specifically the target value that the third control valve needs to achieve during operation. Specifically, the target opening degree is the opening value of the third control valve used to ensure that the temperature difference between the indoor ambient temperature and the set temperature is less than the set value.

[0184] Different second temperatures correspond to different target opening degrees. The target opening degree is positively correlated with the second temperature. Specifically, the correspondence between the second temperature and the target opening degree can be preset or obtained based on the actual operating conditions of the air conditioner (such as air conditioner operating parameters or the ambient temperature of the environment where the air conditioner is located). The correspondence can take the form of a mapping relationship (such as a mapping table), a calculation formula, etc. Based on this correspondence, the target opening degree corresponding to the second temperature can be determined. In this embodiment, the target operating frequency of the compressor can be obtained, and the target correspondence between the second temperature and the target opening degree can be obtained based on the target frequency. Different target frequencies correspond to different target correspondences, and different target frequencies result in different target opening degrees corresponding to the second temperature. Based on the target correspondence, the target opening degree corresponding to the second temperature can be determined.

[0185] The set value can be a pre-set fixed parameter, a parameter set by the user, or a parameter determined based on the human body detection information in the space currently being regulated by the air conditioner.

[0186] In this embodiment, the above method enables the cooling output of the air conditioner during the recovery phase of cooling operation to accurately match the actual needs of the indoor environment, ensuring that the compressor does not stop and the cooling output can continue, preventing excessive fluctuations in indoor temperature and ensuring that indoor users do not feel obvious alternation between hot and cold, thus effectively improving user comfort during the air conditioning cooling operation.

[0187] Furthermore, this invention also proposes a computer-readable storage medium storing a control program for an air conditioner. When the control program is executed by a processor, it implements the relevant steps of any of the above-described air conditioner control methods.

[0188] It should be noted that, in this document, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or system that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or system. Unless otherwise specified, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or system that includes that element.

[0189] The sequence numbers of the above embodiments of the present invention are for descriptive purposes only and do not represent the superiority or inferiority of the embodiments.

[0190] Through the above description of the embodiments, those skilled in the art can clearly understand that the methods of the above embodiments can be implemented by means of software plus necessary general-purpose hardware platforms. Of course, they can also be implemented by hardware, but in many cases the former is a better implementation method. Based on this understanding, the technical solution of the present invention, or the part that contributes to the prior art, can be embodied in the form of a software product. This computer software product is stored in a storage medium (such as ROM / RAM, magnetic disk, optical disk) as described above, and includes several instructions to cause a terminal device (which may be a mobile phone, computer, server, air conditioner, or network device, etc.) to execute the methods described in the various embodiments of the present invention.

[0191] The above are merely preferred embodiments of the present invention and do not limit the scope of the patent. Any equivalent structural or procedural transformations made based on the description and drawings of the present invention, or direct or indirect applications in other related technical fields, are similarly included within the scope of patent protection of the present invention.

Claims

1. A control method for an air conditioner, characterized in that, The air conditioner includes a compressor, an oil separator, a first indoor heat exchanger, and a gas-liquid separator. The refrigerant outlet of the first indoor heat exchanger is connected to the gas-liquid inlet of the gas-liquid separator. The oil outlet of the oil separator is connected to the oil return port of the compressor via a first branch. The air conditioner also includes a flow direction control module and a second branch connected in parallel with the first branch. The second branch is heat-exchange connected to the outlet pipe of the gas-liquid separator. The flow direction control module is used to control the flow direction of the compressor oil flowing out of the oil outlet in the first branch and the second branch. The air conditioner also includes a second indoor heat exchanger. The liquid outlet of the gas-liquid separator is connected to the refrigerant inlet of the second indoor heat exchanger. The refrigerant outlet of the second indoor heat exchanger is connected to the return port of the compressor via a pipeline. The pipeline is connected to the outlet port of the outlet pipe. The control method of the air conditioner includes the following steps: When the air conditioner is in cooling mode, the ambient temperature of the environment where the air conditioner is located is obtained; When the ambient temperature is greater than or equal to a preset temperature threshold, the flow direction control module is controlled to operate so that the compressor oil flowing out of the oil outlet flows through the second branch and exchanges heat with the outlet pipe before entering the return oil port.

2. The control method for an air conditioner as described in claim 1, characterized in that, The flow direction control module includes a first control valve located on the first branch and a second control valve located on the second branch. The step of controlling the operation of the flow direction control module so that the compressor oil flowing out of the oil outlet flows through the second branch and exchanges heat with the outlet pipe before entering the oil return port includes: The first control valve is closed, and the second control valve is opened.

3. The control method for an air conditioner as described in claim 2, characterized in that, After the steps of controlling the first control valve to close and controlling the second control valve to open, the method further includes: Obtain the first return oil temperature of the compressor; The first opening control parameter of the first control valve and the second opening control parameter of the second control valve are determined based on the first return oil temperature. The first control valve is controlled to operate with the first opening control parameter, and the second control valve is controlled to operate with the second opening control parameter, so that the temperature of the compressor oil return is within the target temperature range.

4. The control method for an air conditioner as described in claim 3, characterized in that, The step of determining the first opening control parameter of the first control valve and the second opening control parameter of the second control valve based on the first return oil temperature includes: When the first return oil temperature is less than the minimum value of the target temperature range, determining the first opening control parameter includes opening the first control valve, and determining the second opening control parameter includes closing the second control valve. When the first return oil temperature is greater than the maximum value of the target temperature range, the temperature difference between the first return oil temperature and the maximum value is determined, and the first opening control parameter and the second opening control parameter are determined based on the temperature difference.

5. The control method for an air conditioner as described in claim 4, characterized in that, The first opening control parameter further includes a first target opening degree of the first control valve, and the second opening control parameter includes a second target opening degree of the second control valve. The step of determining the first opening control parameter and the second opening control parameter based on the temperature difference value includes: The first target opening and the second target opening are determined based on the temperature difference value; The first target opening degree is negatively correlated with the temperature difference value, while the second target opening degree is positively correlated with the temperature difference value.

6. The control method for an air conditioner as described in claim 3, characterized in that, After the steps of controlling the first control valve to close and controlling the second control valve to open, the method further includes: Obtain the continuous operating time of the compressor after it starts; When the continuous running time is greater than or equal to the preset duration, the step of obtaining the first oil return temperature of the compressor is performed.

7. The control method for an air conditioner as described in claim 1, characterized in that, After the step of controlling the flow direction control module to operate when the ambient temperature is greater than or equal to a preset temperature threshold, so that the compressor oil flowing out of the oil outlet flows through the second branch and exchanges heat with the outlet pipe before entering the oil return port, the method further includes: Obtain the second return oil temperature and the first discharge temperature of the compressor; When the second return oil temperature is greater than the first preset temperature, and the first exhaust temperature is greater than the second preset temperature, the compressor is controlled to operate at a reduced frequency.

8. The control method for an air conditioner as described in claim 7, characterized in that, The steps for controlling the compressor to operate at reduced frequency include: The compressor is controlled to operate at a reduced frequency at a first target rate, which is greater than a preset rate.

9. The control method for an air conditioner as described in claim 7, characterized in that, After the step of controlling the compressor to operate at a reduced frequency, the method further includes: Obtain the third oil return temperature and the second exhaust temperature of the compressor; When the third return oil temperature is less than the third preset temperature and the second exhaust temperature is less than the fourth preset temperature, the compressor is controlled to operate at a second target rate. Wherein, the third preset temperature is less than the first preset temperature, the fourth preset temperature is less than the second preset temperature, and the second target rate is less than or equal to the preset rate.

10. The control method for an air conditioner as described in claim 7, characterized in that, After the step of obtaining the second return oil temperature and the first discharge temperature of the compressor, the method further includes: When the second return oil temperature is greater than the fifth preset temperature and the first exhaust temperature is greater than the sixth preset temperature, the compressor is controlled to stop. When the second return oil temperature is less than or equal to the fifth preset temperature, and / or when the first exhaust temperature is less than or equal to the sixth preset temperature, the step of controlling the compressor to operate at a reduced frequency at the first target rate when the second return oil temperature is greater than the first preset temperature and the first exhaust temperature is greater than the second preset temperature is executed. The fifth preset temperature is greater than the first preset temperature, and the sixth preset temperature is greater than the second preset temperature.

11. The control method for an air conditioner as described in claim 1, characterized in that, After the step of obtaining the ambient temperature of the environment where the air conditioner is located when the air conditioner is in cooling operation, the method further includes: When the ambient temperature is lower than the preset temperature threshold, the flow direction control module is controlled to operate so that the compressor oil flowing out of the outlet flows through the first branch and enters the return oil port.

12. The control method for an air conditioner as described in claim 11, characterized in that, The flow direction control module includes a first control valve located on the first branch and a second control valve located on the second branch. The step of controlling the operation of the flow direction control module to cause the oil flowing out of the compressor outlet to flow through the first branch and enter the oil return port includes: The first control valve is opened, and the second control valve is closed.

13. The control method for an air conditioner as described in any one of claims 1 to 12, characterized in that, After the step of obtaining the ambient temperature of the environment where the air conditioner is located when the air conditioner is in cooling operation, the method further includes: When the ambient temperature is greater than or equal to a preset temperature threshold, the outdoor fan of the air conditioner is controlled to run at a target speed, and the flow direction control module is executed to make the compressor oil flowing out of the oil outlet flow through the second branch and exchange heat with the outlet pipe before entering the oil return port. The target rotational speed is greater than the preset rotational speed.

14. The control method for an air conditioner as described in any one of claims 1 to 12, characterized in that, The air outlet pipe is equipped with a third control valve, and the control method of the air conditioner further includes: When the air conditioner is in cooling mode, the third control valve is opened.

15. An air conditioner, characterized in that, The air conditioner includes: compressor; First indoor heat exchanger; A gas-liquid separator, wherein the refrigerant outlet of the first indoor heat exchanger is connected to the gas-liquid inlet of the gas-liquid separator; An oil separator, wherein the oil outlet of the oil separator is connected to the oil return port of the compressor via a first branch; The second branch is connected in parallel with the first branch and is heat-exchange connected to the outlet pipe of the gas-liquid separator. A flow direction control module is used to control the flow direction of the compressor oil flowing out of the oil outlet in the first branch and the second branch. The second indoor heat exchanger has its liquid outlet connected to the refrigerant inlet of the gas-liquid separator, and its refrigerant outlet connected to the return port of the compressor via a pipeline, which is connected to the outlet of the outlet pipe. A control device is provided, wherein the compressor and the flow control module are both connected to the control device. The control device includes: a memory, a processor, and an air conditioner control program stored in the memory and executable on the processor. When the air conditioner control program is executed by the processor, it implements the steps of the air conditioner control method as described in any one of claims 1 to 14.

16. The air conditioner as described in claim 15, characterized in that, The flow direction control module includes a first control valve located on the first branch and a second control valve located on the second branch, both of which are connected to the control device. And / or, the air conditioner further includes a second indoor heat exchanger, the liquid outlet of the gas-liquid separator is connected to the refrigerant inlet of the second indoor heat exchanger, the refrigerant outlet of the second indoor heat exchanger is connected to the return port of the compressor through a pipeline, and the pipeline is connected to the outlet of the outlet pipe; And / or, the air outlet pipe is equipped with a third control valve, which is connected to the control device.

17. The air conditioner as described in claim 15 or 16, characterized in that, The air conditioner is a base station air conditioner, which includes an indoor unit. The compressor, the oil separator, the first indoor heat exchanger, the gas-liquid separator, the second branch circuit, and the flow direction control module are all located in the indoor unit.

18. A computer-readable storage medium, characterized in that, The computer-readable storage medium stores a control program for an air conditioner, which, when executed by a processor, implements the steps of the control method for an air conditioner as described in any one of claims 1 to 14.

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