CN114923273B

CN114923273B - Air conditioning system and control method thereof

Info

Publication number: CN114923273B
Application number: CN202210488219.5A
Authority: CN
Inventors: 颜鹏; 孙杨; 韩飞; 李文阳
Original assignee: Qingdao Hisense Hitachi Air Conditioning System Co Ltd
Current assignee: Qingdao Hisense Hitachi Air Conditioning System Co Ltd
Priority date: 2022-05-06
Filing date: 2022-05-06
Publication date: 2023-11-07
Anticipated expiration: 2042-05-06
Also published as: CN114923273A

Abstract

The embodiment of the application discloses an air conditioning system and a control method thereof, which relate to the technical field of household appliances and can reduce the cost of oil return control of the air conditioning system. The air conditioning system includes: a refrigerant circulation loop for circulating the refrigerant in a loop formed by the compressor, the condenser, the electronic expansion valve, the evaporator, the four-way valve and the gas-liquid separator; the compressor is used for compressing the low-temperature low-pressure refrigerant gas into high-temperature high-pressure refrigerant gas and discharging the high-temperature high-pressure refrigerant gas to the condenser; a first temperature sensor for detecting an exhaust temperature of the compressor; the second temperature sensor is used for detecting the oil return temperature after the first capillary tube between the compressor and the gas-liquid separator; a controller configured to: acquiring an exhaust temperature through a temperature sensor; predicting the oil temperature in an oil pool of the compressor according to the exhaust temperature; and determining whether the air conditioning system enters an oil return mode according to the relation between the oil return temperature and the oil temperature.

Description

Air conditioning system and control method thereof

Technical Field

The application relates to the technical field of household appliances, in particular to an air conditioning system and a control method thereof.

Background

With the development of economy and society, air conditioners are increasingly used in various places such as entertainment, home, work and the like. In the operation process of the air conditioning system, most of the lubricating oil carried out of the compressor by the refrigerant returns to the compressor along with the refrigerant, but a small part of the lubricating oil can be carried into the engine body along with the refrigerant from the exhaust pipe orifice, so that the phenomenon that the compressor is worn or even burnt out due to the operation oil shortage is caused, and therefore, oil return control is needed in the operation process of the air conditioning system.

In the related art, when the oil return control is performed on an air conditioning system, an oil level sensor is installed in an oil sump of a compressor, and the condition of the oil level in the compressor is obtained in real time through the oil level sensor, so that whether the compressor needs oil return or not is judged, but the cost for installing the oil level sensor in the oil sump of the compressor is high.

Disclosure of Invention

The embodiment of the application provides an air conditioning system and a control method thereof, which are used for reducing the cost while realizing oil return control of the air conditioning system.

In a first aspect, an embodiment of the present application provides an air conditioning system, including: a refrigerant circulation loop for circulating the refrigerant in a loop formed by the compressor, the condenser, the electronic expansion valve, the evaporator, the four-way valve and the gas-liquid separator; the compressor is used for compressing the low-temperature low-pressure refrigerant gas into high-temperature high-pressure refrigerant gas and discharging the high-temperature high-pressure refrigerant gas to the condenser; an outdoor heat exchanger and an indoor heat exchanger, wherein one of the two heat exchangers works as a condenser and the other works as an evaporator; a first temperature sensor for detecting an exhaust temperature of an exhaust port of the compressor; the second temperature sensor is used for detecting the oil return temperature after the first capillary tube between the compressor and the gas-liquid separator; a controller configured to: acquiring an exhaust temperature through a first temperature sensor; predicting the oil temperature in an oil pool of the compressor according to the exhaust temperature; acquiring an oil return temperature through a second temperature sensor; and determining whether the air conditioning system enters an oil return mode according to the relation between the oil return temperature and the oil temperature.

The technical scheme provided by the embodiment of the application at least has the following beneficial effects: according to the air conditioning system disclosed by the application, the oil temperature is predicted through the exhaust temperature, and an oil level sensor is not required to be additionally arranged in the compressor, so that the cost is saved. In addition, the air conditioning system can determine whether the air conditioning system enters an oil return mode according to the relation between the oil return temperature and the oil temperature, and can realize oil return control of the air conditioning system while reducing cost.

In some embodiments, the exhaust temperature and the oil temperature satisfy the following correspondence:

wherein,is the exhaust temperature; />Is the oil temperature; />、/>Are all preset constants.

In some embodiments, the controller is configured to determine whether the air conditioning system enters the oil return mode according to a relationship between the oil return temperature and the oil temperature, and specifically performs the following steps: and when the difference value between the oil temperature and the oil return temperature is out of the preset range, controlling the air conditioning system to enter an oil return mode.

It will be appreciated that when the difference between the oil temperature and the return oil temperature is outside the preset range, the compressor is operating abnormally and lacks lubrication oil. The air conditioning system is thus controlled to enter an oil return mode to compensate for the lack of oil in the compressor.

In some embodiments, the controller is configured to determine whether the air conditioning system enters the oil return mode according to a relationship between the oil return temperature and the oil temperature, and specifically performs the following steps: and when the difference between the oil temperature and the oil return temperature is within a preset range, controlling the air conditioning system to keep the current working mode.

It should be understood that when the difference between the oil temperature and the return oil temperature is within the preset range, the compressor normally operates, so that the air conditioning system keeps the current working mode to normally operate.

In some embodiments, the controller is configured to control the air conditioning system to enter the oil return mode, and specifically performs the following steps: and controlling the operation frequency of the compressor to be increased to a first frequency, and controlling the compressor to operate at the first frequency for a first preset time period.

It should be appreciated that controlling the compressor to increase the frequency to the first frequency may cause the refrigerant circulation loop to flow at a high rate, thereby bringing the lubricant back to the compressor through the high rate flow of refrigerant. The first preset time period is continued to ensure that the air conditioning system has enough time to bring the lubricating oil back to the compressor through the refrigerant circulation loop.

In some embodiments, the controller is configured to predict the oil temperature in the oil sump of the compressor based on the discharge temperature, and specifically performs the following steps: and when the duration time that the operating frequency of the compressor is smaller than the second frequency is longer than the second preset duration time, predicting the oil temperature in the oil pool of the compressor according to the exhaust temperature.

It will be appreciated that if the duration of time that the operating frequency of the compressor is less than the second frequency is greater than the second predetermined duration, then this indicates that the compressor is continuously operating at too low a frequency and that there may be a lack of lubrication oil due to abnormal operation of the compressor. Therefore, the oil temperature in the oil sump of the compressor is predicted according to the exhaust temperature so as to further judge whether the compressor of the air conditioning system has the oil shortage phenomenon.

In a second aspect, an embodiment of the present application provides a control method of an air conditioning system, including: acquiring the exhaust temperature of an exhaust port of a compressor of an air conditioning system; predicting the oil temperature in an oil pool of the compressor according to the exhaust temperature; acquiring the oil return temperature of a first capillary tube between a compressor of an air conditioning system and a gas-liquid separator; and determining whether the air conditioning system enters an oil return mode according to the relation between the oil return temperature and the oil temperature.

In some embodiments, determining whether the air conditioning system enters the oil return mode according to the relationship between the oil return temperature and the oil temperature includes: and when the difference value between the oil temperature and the oil return temperature is out of the preset range, controlling the air conditioning system to enter an oil return mode.

In some embodiments, determining whether the air conditioning system enters the oil return mode according to the relationship between the oil return temperature and the oil temperature includes: and when the difference between the oil temperature and the oil return temperature is within a preset range, controlling the air conditioning system to keep the current working mode.

In some embodiments, the controlling the air conditioning system to enter the oil return mode includes: and controlling the operation frequency of the compressor to be increased to a first frequency, and controlling the compressor to operate at the first frequency for a first preset time period.

In some embodiments, predicting the oil temperature in the oil sump of the compressor based on the discharge temperature includes: and when the duration time that the operating frequency of the compressor is smaller than the second frequency is longer than the second preset duration time, predicting the oil temperature in the oil pool of the compressor according to the exhaust temperature.

In a third aspect, an embodiment of the present application provides a control apparatus for an air conditioning system, including: one or more processors; one or more memories; wherein the one or more memories are configured to store computer program code comprising computer instructions that, when executed by the one or more processors, cause the controller to perform the method provided in the second aspect and possible implementations.

In a fourth aspect, embodiments of the present application provide a computer-readable storage medium comprising computer instructions which, when run on a computer, cause the computer to perform the method provided in the second aspect and in a possible implementation.

In a fifth aspect, embodiments of the present application provide a computer program product comprising computer instructions which, when run on a computer, cause the computer to perform the method provided in the second aspect and possible implementations described above.

It should be noted that the above-mentioned computer instructions may be stored in whole or in part on a computer-readable storage medium. The computer readable storage medium may be packaged together with the processor of the controller or may be packaged separately from the processor of the controller, which is not limited in the present application.

The advantageous effects described in the second to fifth aspects of the present application may be referred to for the advantageous effect analysis of the first aspect, and will not be described here again.

Drawings

The accompanying drawings are included to provide a further understanding of the application and are incorporated in and constitute a part of this specification, illustrate and do not limit the application.

Fig. 1 is a schematic diagram of a refrigerant circulation principle of an air conditioning system according to some embodiments;

FIG. 2 is a schematic diagram of a refrigerant circulation principle of another air conditioning system according to some embodiments;

FIG. 3 (a) is a schematic diagram of a multi-split air conditioning system according to some embodiments;

FIG. 3 (b) is a schematic diagram II of another multi-split air conditioning system according to some embodiments;

FIG. 3 (c) is a schematic diagram III of a multi-split air conditioning system according to yet another embodiment;

FIG. 4 is a schematic diagram of interactions between a controller and a terminal device of an air conditioning system according to some embodiments;

FIG. 5 is a schematic diagram of a management interface of a terminal device according to some embodiments;

FIG. 6 is a second diagram of a management interface of another terminal device according to some embodiments;

FIG. 7 is a flow chart of a method of controlling an air conditioning system according to some embodiments;

FIG. 8 is a second flow chart of a control method of another air conditioning system according to some embodiments;

FIG. 9 is a schematic diagram of a compressor discharge temperature versus oil temperature according to some embodiments;

FIG. 10 is a second schematic diagram of interactions between a controller and a terminal device of another air conditioning system according to some embodiments;

FIG. 11 is a schematic structural view of a control device according to some embodiments;

fig. 12 is a schematic diagram of a hardware architecture of a controller according to some embodiments.

Reference numerals illustrate:

a 101-compressor; 102-a four-way valve; 103-an indoor heat exchanger; 104-an electronic expansion valve; 105-outdoor heat exchanger; 106-a gas-liquid separator; 107-oil separator; 108-an indoor fan; 109-an outdoor fan; 110-a first temperature sensor; 111-a one-way valve; 112-a second temperature sensor; 113-a first capillary; 114-a second capillary.

Detailed Description

The following description of the embodiments of the present application will be made clearly and completely with reference to the accompanying drawings, in which it is apparent that the embodiments described are only some embodiments of the present application, but not all embodiments. All other embodiments, which can be made by those skilled in the art based on the embodiments of the application without making any inventive effort, are intended to be within the scope of the application.

The terms "first," "second," and the like, are used for descriptive purposes only and are not to be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defining "a first" or "a second" may explicitly or implicitly include one or more such feature. In the description of the present application, unless otherwise indicated, the meaning of "a plurality" is two or more.

In the description of the present application, it should be noted that, unless explicitly stated and limited otherwise, the terms "connected," "connected," and "connected" are to be construed broadly, and may be, for example, fixedly connected, detachably connected, or integrally connected. The specific meaning of the above terms in the present application will be understood in specific cases by those of ordinary skill in the art. In addition, when describing a pipeline, the terms "connected" and "connected" as used herein have the meaning of conducting. The specific meaning is to be understood in conjunction with the context.

Throughout the specification and claims, unless the context requires otherwise, the word "comprise" and its other forms such as the third person referring to the singular form "comprise" and the present word "comprising" are to be construed as open, inclusive meaning, i.e. as "comprising, but not limited to. In the description of the specification, the terms "one embodiment", "some embodiments", "exemplary embodiment", "example", "specific example", "some examples", "and the like are intended to indicate that a particular feature, structure, material, or characteristic associated with the embodiment or example is included in at least one embodiment or example of the present disclosure. The schematic representations of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the particular features, structures, materials, or characteristics may be combined in any suitable manner in any one or more embodiments or examples.

In embodiments of the application, words such as "exemplary" or "such as" are used to mean serving as an example, instance, or illustration. Any embodiment or design described herein as "exemplary" or "e.g." in an embodiment should not be taken as preferred or advantageous over other embodiments or designs. Rather, the use of words such as "exemplary" or "such as" is intended to present related concepts in a concrete fashion.

As shown in the background art, in the operation process of the air conditioning system, the lubricating oil of the compressor is discharged out of the compressor along with the refrigerant, and only the discharged lubricating oil can be smoothly brought back into the compressor, so that the dynamic balance of the oil of the whole system can be maintained, otherwise, the compressor can be damaged due to oil shortage. Therefore, oil return control is required during operation of the air conditioning system.

In the related art, when the oil return control is performed on the air conditioning system, the condition of the oil level in the compressor is obtained in real time through the oil level sensor, so that whether the compressor needs oil return or not is judged. However, this requires the installation of an oil level sensor in the sump of the compressor, so that the air conditioning system requires a high cost to accomplish the oil return control.

In view of the above, an embodiment of the present application provides an air conditioning system, where the air conditioning system obtains an exhaust temperature through a temperature sensor disposed at an exhaust port of a compressor, predicts an oil temperature in an oil sump of the compressor according to the exhaust temperature, and further determines whether the compressor needs oil return according to the predicted oil temperature and an oil return temperature of the compressor. Therefore, an oil level sensor is not required to be additionally arranged in the compressor, and oil return control of the air conditioning system is realized while the cost is reduced.

For further describing the scheme of the present application, fig. 1 and fig. 2 show schematic diagrams of refrigerant circulation of an air conditioning system according to an embodiment of the present application, where the schematic diagram shown in fig. 1 is a schematic diagram of refrigerant circulation in a cooling mode of the air conditioning system, and the schematic diagram shown in fig. 2 is a schematic diagram of refrigerant circulation in a heating mode of the air conditioning system.

Referring to fig. 1 or 2, the air conditioning system 100 may include: a compressor 101, a four-way valve 102, an indoor heat exchanger 103, an electronic expansion valve 104, an outdoor heat exchanger 105, a gas-liquid separator 106, and a controller (not shown in fig. 1). In some embodiments, the air conditioning system 100 further includes an oil separator 107, an indoor fan 108, an outdoor fan 109, a first temperature sensor 110, a check valve 111, a second temperature sensor 112, a first capillary tube 113, and a second capillary tube 114. The internal structure of the air conditioning system 100 and the principle of refrigerant circulation will be described below by taking a refrigeration cycle as an example.

In some embodiments, the compressor 101 is disposed between the gas-liquid separator 106 and the outdoor heat exchanger 105 for powering the refrigerant cycle. The compressor 101 compresses a low-pressure refrigerant sent from the gas-liquid separator 106, and sends the compressed refrigerant to the outdoor heat exchanger 105 through the four-way valve 102. Alternatively, the compressor 101 may be a variable capacity inverter compressor controlled based on the rotational speed of the inverter.

In some embodiments, four ports of the four-way valve 102 are connected to the compressor 101, the outdoor heat exchanger 105, the gas-liquid separator 106, and the indoor heat exchanger 103, respectively. The four-way valve 102 is used for realizing the mutual conversion between a refrigerating mode and a heating mode by changing the flow direction of a refrigerant in a system pipeline. Illustratively, referring to fig. 1, when the D end and the C end of the four-way valve are in communication, the a end and the B end are in communication, the air conditioning system 100 operates in refrigeration, and the circulation direction of the refrigerant circulation circuit is shown by the arrow in fig. 1. Referring to fig. 2, when the D end and the a end of the four-way valve are connected, the C end and the B end are connected, the air conditioning system is operated to heat, and the flowing direction of the refrigerant circulation circuit is shown by the arrow in fig. 2.

In some embodiments, the indoor heat exchanger 103 is configured to exchange heat between a refrigerant flowing in a heat transfer tube of the indoor heat exchanger and indoor air, and in the cooling mode, the indoor heat exchanger 103 operates as an evaporator, and in the heating mode, the indoor heat exchanger 103 operates as a condenser.

In some embodiments, the electronic expansion valve 104 is disposed between the indoor heat exchanger 103 and the outdoor heat exchanger 105, and has a function of expanding and decompressing the refrigerant flowing through the electronic expansion valve 104, and can be used to adjust the supply amount of the refrigerant in the pipeline. Alternatively, the air conditioning system 100 may be provided with a plurality of electronic expansion valves. When the electronic expansion valve 104 decreases in opening, the flow path resistance of the refrigerant passing through the electronic expansion valve 104 increases. When the electronic expansion valve 104 increases in opening degree, the flow path resistance of the refrigerant passing through the electronic expansion valve 104 decreases. In this way, even if the state of other devices in the circuit is not changed, when the opening degree of the electronic expansion valve 104 is changed, the flow rate of the refrigerant flowing to the indoor heat exchanger 103 or the outdoor heat exchanger 105 is also changed. It should be noted that the number of electronic expansion valves 104 shown in fig. 1 or fig. 2 is merely an example, and the present application is not limited thereto.

In some embodiments, the outdoor heat exchanger 105 is connected to the compressor 101 through the four-way valve 102 at one end and to the indoor heat exchanger 103 through the electronic expansion valve 104 at the other end. The outdoor heat exchanger 105 is configured to exchange heat between the outdoor air and the refrigerant flowing through the heat transfer pipe of the outdoor heat exchanger, and in the cooling mode, the outdoor heat exchanger 105 operates as a condenser; in the heating mode, the outdoor heat exchanger 105 operates as an evaporator.

In some embodiments, one end of the gas-liquid separator 106 is connected to the suction inlet of the compressor 101, and the other end is connected to the oil separator 107 through a communication oil separator. In the gas-liquid separator 106, the refrigerant flowing from the indoor heat exchanger 103 to the compressor 101 through the four-way valve 102 is separated into a gas refrigerant and a liquid refrigerant by the gas-liquid separator 106. The gas refrigerant is mainly supplied from the gas-liquid separator 106 to the suction port of the compressor 101.

In some embodiments, one end of the oil separator 107 is communicated with the output port of the compressor 101, and separates lubricating oil in the refrigerant conveyed by the output port of the compressor 101; the other end of the oil separator 107 is connected to the four-way valve 102, and as shown in fig. 1, the refrigerant after oil separation is sent to the outdoor heat exchanger 105 through the four-way valve 102 during cooling; as shown in fig. 2, the refrigerant after oil separation is performed during heating is sent to the indoor heat exchanger 103 through the four-way valve 102.

In some embodiments, the indoor fan 108 generates an airflow of the indoor air passing through the indoor heat exchanger 103 to promote heat exchange of the refrigerant flowing in the heat transfer tubes of the indoor heat exchanger 103 with the indoor air.

In some embodiments, the outdoor fan 109 generates an airflow of the outdoor air through the outdoor heat exchanger 105 to promote heat exchange of the refrigerant flowing in the heat transfer tubes of the outdoor heat exchanger 105 with the outdoor air.

In some embodiments, a first temperature sensor 110 is provided at the discharge port of the compressor 101 for detecting the discharge temperature of the discharge port of the compressor.

In some embodiments, the check valve 111 is disposed between the oil separator 107 and the four-way valve 102, and is used for ensuring that the refrigerant discharged by the compressor flows to the D end of the four-way valve 102 to participate in the refrigerant circulation after being separated by the oil separator 107, so as to avoid the refrigerant backflow in the refrigerant circulation process.

In some embodiments, a first capillary tube 113 is disposed between the compressor 101 and the gas-liquid separator 106 for reducing the pressure of the refrigerant in the conduit.

In some embodiments, a second temperature sensor 112 is disposed between the first capillary tube 113 and the gas-liquid separator 106 for detecting the return oil temperature after the first capillary tube between the compressor and the gas-liquid separator. It should be understood that the oil return temperature here is the temperature of the mixture of the refrigerant and the lubricating oil in the pipe between the first capillary tube 113 and the gas-liquid separator 106.

In some embodiments, a second capillary tube 114 is disposed between the oil separator 107 and the gas-liquid separator 106 for reducing the pressure of the refrigerant in the conduit.

In some embodiments, the air conditioning system 100 further includes a filter for filtering impurities and dirt in the air conditioning system pipeline during the circulation of the refrigerant, so as to ensure that the refrigerant flows smoothly without affecting the normal operation due to blockage. Alternatively, the air conditioning system 100 may be provided with a plurality of filters.

In some embodiments, the air conditioning system 100 further includes an indoor fan motor coupled to the indoor fan 108 for driving or varying the rotational speed of the indoor fan.

In some embodiments, the air conditioning system 100 further includes an outdoor fan motor coupled to the outdoor fan 109 for driving or varying the rotational speed of the outdoor fan.

In some embodiments, the air conditioning system 100 further includes a display. The display is electrically connected with the controller. Optionally, a display is used to display a control panel of the air conditioning system 100, for example, the display may be used to display the indoor temperature or the current mode of operation. Optionally, the display is connected to the controller, and the user can perform operations and set programs on the control panel through the display. Optionally, the display further includes a pressure sensor or a temperature sensor, and the display may transmit a user instruction to the control according to a gesture operation of the user, such as pressing a key, so as to implement a man-machine interaction function. Alternatively, the display may be a liquid crystal display, an organic light-emitting diode (OLED) display. The particular type, size, resolution, etc. of the display are not limited, and those skilled in the art will appreciate that the display may be modified in performance and configuration as desired.

In some embodiments, the air conditioning system 100 further includes a high pressure switch, where an electrical connection exists between the high pressure switch and the controller, and the high pressure switch is used to monitor the pressure of the air conditioning pipeline, and when the pipeline pressure of the air conditioning system 100 is abnormal, send abnormal information to the controller, so that the controller controls the system to stop, and ensure the normal operation of the air conditioning system 100.

In some embodiments, the controller refers to a device that may generate an operation control signal, instructing the air conditioning system 100 to execute a control instruction, based on the instruction operation code and the timing signal. By way of example, the controller may be a central processing unit (central processing unit, CPU), a general purpose processor network processor (network processor, NP), a digital signal processor (digital signal processing, DSP), a microprocessor, a microcontroller, a programmable logic device (programmable logic device, PLD), or any combination thereof. The controller may also be any other device having processing functionality, such as a circuit, device or software module, for which embodiments of the application are not limited in any way.

Although not shown in fig. 1 and 2, the air conditioning system 100 may further include a power supply device (such as a battery and a power management chip) for supplying power to the respective components, and the battery may be logically connected to the controller through the power management chip, thereby performing functions of power consumption management and the like of the air conditioning system 100 through the power supply device.

In addition, as shown in fig. 3 (a), the air conditioning system 100 may be further extended to a multi-split air conditioning system. Further, as shown in fig. 3 (b) or 3 (c), the air conditioning system may further include a plurality of compressors. The present application does not particularly limit the number of indoor units and the number of compressors of the air conditioning system.

Fig. 4 is a schematic interaction diagram of a controller 200 and a terminal device 300 of an air conditioning system according to an embodiment of the present application.

As shown in fig. 4, the terminal device 300 may establish a communication connection with the controller 200 of the air conditioning system. By way of example, the establishment of the communication connection may be accomplished using any known network communication protocol. The network communication protocol may be various wired or wireless communication protocols such as Ethernet, universal serial bus (universal serial bus, USB), FIREWIRE (FIREWIRE), any cellular network communication protocol (e.g., 3G/4G/5G), bluetooth, wireless Fidelity (wireless fidelity, wi-Fi), NFC, or any other suitable communication protocol. The communication connection may be a bluetooth connection, NFC, zigbee, wireless fidelity (wireless fidelity, wi-Fi), or the like. The embodiment of the present application is not particularly limited thereto.

It should be noted that the terminal device 300 shown in fig. 4 is only one example of a terminal device. The terminal device 300 in the present application may be a remote controller, a mobile phone, a tablet computer, a personal computer (personal computer, PC), a personal digital assistant (personal digital assistant, PDA), a smart watch, a netbook, a wearable electronic device, an augmented reality (augmented reality, AR) device, a Virtual Reality (VR) device, a robot, etc., and the present application does not limit the specific form of the terminal device.

Taking the terminal device 300 as a mobile phone as an example, in some embodiments, the operation mode of the air conditioning system may be set by the terminal device. Illustratively, as shown in fig. 5, a management interface 301 of the air conditioning system is displayed on the terminal device, and the management interface 301 includes a key 302 of "mode management". It is detected that the user clicks the "mode management" button 302 in the management interface 301, and the terminal device pulls up the selection box 303 in the management interface 301 in the pop-up operation mode. After detecting that the user pulls down the selection instruction of the selection box 303 in the operation mode, the terminal device sends an instruction to the air conditioning system to complete the setting of the operation mode.

In some embodiments, a user may turn on the oil return detection function through a management interface of the terminal device 300 to enable the air conditioning system to automatically detect whether the oil pool of the compressor is starved of oil. As shown in fig. 6, the management interface 301 of the terminal device includes an "oil return detection function" button, the button 3041 shown in fig. 6 is in an off state of the "oil return detection function" button, the terminal device detects that the user clicks a switch of the "oil return detection function" button, changes the state of the "oil return detection function" button into an on state shown in 3042, and transmits an instruction of the on detection to the air conditioning system, so that the air conditioning system enters automatic oil return detection.

The embodiments of the present application will be described in detail below with reference to the drawings attached to the specification.

As shown in fig. 7, an embodiment of the present application provides a control method of an air conditioning system, which is used for a controller of the air conditioning system to control oil return of the air conditioning system, and the method includes:

s101, the controller obtains the exhaust temperature of an exhaust port of a compressor of the air conditioning system.

In some embodiments, the air conditioning system is provided with a first temperature sensor at the discharge port of the compressor, the first temperature sensor being electrically connected to the controller. The controller controls the first temperature sensor to detect the exhaust temperature of the exhaust port of the compressor, and obtains the exhaust temperature detected by the first temperature sensor.

In some examples, the controller controls the first temperature sensor to detect the exhaust temperature of the exhaust port of the compressor N times within the third preset period, and takes an average value of the detected exhaust temperatures N times as the exhaust temperature acquired by the controller, where N is a positive integer greater than 2. In this way, the accuracy of exhaust gas temperature measurement can be improved.

S102, the controller predicts the oil temperature in the oil pool of the compressor according to the exhaust temperature.

In some embodiments, the controller obtains a preset relationship between the discharge temperature and the oil temperature before predicting the oil temperature of the compressor, and predicts the oil temperature of the compressor based on the discharge temperature and the preset relationship between the discharge temperature and the oil temperature. Further, a preset relationship between the exhaust temperature and the oil temperature may be pre-stored in the controller.

In some embodiments, the predetermined relationship between the exhaust temperature and the oil temperature is determined according to historical data of the exhaust temperature and the oil temperature. The history data includes: a plurality of exhaust temperature values and oil temperature values corresponding to the exhaust temperatures.

Further, when the preset relation between the exhaust temperature and the oil temperature of the air conditioning system is determined, a third temperature sensor is further arranged in the oil pool of the compressor of the air conditioning system so as to obtain the oil temperature in the oil pool of the compressor. It should be understood that the third temperature sensor described above is not necessarily present in the air conditioning system shown in the present application. The third temperature sensor is disposed in an oil sump of a compressor of the model machine of the air conditioning system, and the first temperature sensor is disposed at an exhaust port of the compressor of the model machine, so as to determine a preset relationship between the exhaust temperature and the oil temperature according to historical data of the exhaust temperature and the oil temperature. In practical application, only the preset relation between the exhaust temperature and the oil temperature is needed, so that the air conditioning system disclosed by the application does not comprise the third temperature sensor and only the preset relation between the exhaust temperature and the oil temperature determined by the model machine is stored.

In some embodiments, the above-mentioned determining the preset relationship between the exhaust temperature and the oil temperature according to the historical data of the exhaust temperature and the oil temperature may be specifically implemented as: and determining the preset relation between the exhaust temperature and the oil temperature through a plurality of analysis models such as a combination model, a neural network, a regression analysis model, a dynamic analysis model and the like according to the historical data of the exhaust temperature and the oil temperature. The present application is not limited to a specific algorithm for predicting the oil temperature based on the exhaust temperature.

The method for confirming the preset relationship between the exhaust temperature and the oil temperature will be specifically described below by taking a regression analysis model as an example. Where regression analysis refers to a statistical analysis method that determines the quantitative relationship of interdependence between two or more variables. In big data analysis, regression analysis is a predictive modeling technique that researches on the relationship between dependent and independent variables, generally seeks an approximate expression of the relationship between the variables according to statistical data, and uses the obtained approximate expression to perform statistical description, analysis and inference, solving the problems of prediction, control and optimization.

For example, with the exhaust temperature as an independent variable and the oil temperature of the oil sump in the compressor as a dependent variable, as shown in fig. 8, confirming the preset relationship between the exhaust temperature and the oil temperature according to the regression analysis method may be specifically implemented as the following steps Sa1 to Sa4:

sa1, preprocessing the collected historical data of exhaust gas temperature and oil temperature.

Illustratively, the preprocessing includes culling of erroneous data and anomalous data.

Sa2, setting a regression prediction model according to historical data and relation between the exhaust temperature and the oil temperature after pretreatment.

In some examples, the mathematical model set is a mathematical model that may be commonly used for regression analysis methods. For example: linear regression models, polynomial regression models, exponential regression models, logistic regression models, exponentiation regression models, and S-type regression models, etc. The application is not limited in this regard.

In some examples, historical data of the discharge temperature of the compressor versus the oil temperature is plotted as a scatter plot, with the discharge temperature of the compressor versus the oil temperature as shown in fig. 9. Wherein the horizontal axis is the discharge temperature of the compressor dischargeThe units are in degrees celsius; the vertical axis is the oil temperature in the compressor oil sump +.>The unit is in degrees Celsius. Then, according to the scatter diagram distribution of the historical data of the exhaust temperature and the oil temperature shown in fig. 9, it can be determined that the historical data of the exhaust temperature and the oil temperature is concentrated near the dotted curve shown in fig. 9, and according to the concentration of the scatter diagram, the regression prediction model can be preliminarily set as a linear regression model, a polynomial regression model or an exponential regression model. It should be understood that the model selection shown in fig. 9 is merely an example, and different mathematical models may be selected according to different data dispersion or concentration situations in actual prediction, which is not limited by the present application.

Sa3, performing correlation analysis.

It is to be understood that it is possible to determine whether the exhaust gas temperature is related to the oil temperature, how much, etc. is related by the correlation analysis. The regression prediction model established is meaningful only when there is indeed some relationship between the exhaust temperature and the oil temperature.

Sa4, calculating a prediction error, and determining a final prediction model according to the prediction error.

In some embodiments, step Sa4 is embodied as: calculating a model prediction error; if the prediction error meets the preset error range, the regression prediction model is used as a final prediction model; if the prediction error does not meet the preset error range, the steps Sa2 to Sa4 are performed.

In other embodiments, steps Sa2 to Sa3 described above may also be implemented as: and setting a plurality of regression prediction models according to historical data and relation between the preprocessed exhaust temperature and the preprocessed oil temperature. And carrying out correlation analysis on each regression prediction model. Step Sa4 is specifically implemented as: and calculating the prediction error of each regression prediction model, and taking the regression model with the minimum prediction error as the final prediction model.

It will be appreciated that whether a regression prediction model is usable for actual prediction depends on the verification of the regression prediction model and the calculation of the prediction error. The regression prediction equation can be used as a final prediction model for prediction only through various tests and with small prediction errors.

It should be noted that, the algorithm for confirming the preset relationship between the exhaust temperature and the oil temperature provided in the present application is merely an example, and it is obvious that the described embodiments are only some embodiments, but not all embodiments of the present application. For example, based on the regression analysis algorithm shown in the present application, one skilled in the art will readily recognize that some steps may be modified or other similar analysis methods may be substituted for the regression analysis methods shown in the present application. It should be understood that all other embodiments that may be made by those of ordinary skill in the art without inventive effort are within the scope of the present application.

In some embodiments, the following correspondence between the predicted discharge temperature of the compressor and the oil temperature in the oil sump of the compressor is satisfied by the air conditioning system:

S103, the controller obtains the oil return temperature after the first capillary tube between the compressor of the air conditioning system and the gas-liquid separator.

In some embodiments, the air conditioning system is provided with a second temperature sensor for detecting the return oil temperature, the second temperature sensor being electrically connected to the controller. The controller controls the second temperature sensor to detect the oil return temperature of the first capillary tube between the compressor and the gas-liquid separator, and obtains the oil return temperature detected by the second temperature sensor. The oil return temperature after the first capillary tube is the temperature of the mixture of the refrigerant and the lubricating oil in the pipeline between the first capillary tube and the gas-liquid separator.

In some examples, the controller controls the second temperature sensor to detect the oil return temperature after the first capillary tube between the compressor and the gas-liquid separator for P times within a fourth preset period, and takes the average value of the oil return temperatures detected for P times as the oil return temperature obtained by the controller, where P is a positive integer greater than 2. In this way, the accuracy of the return oil temperature measurement can be improved.

And S104, the controller determines whether the air conditioning system enters an oil return mode according to the relation between the oil return temperature and the oil temperature.

In some embodiments, the controller controls the air conditioning system to maintain the current operation mode when a difference between the oil temperature and the return oil temperature is within a preset range.

Illustratively, if the oil temperature isAnd oil return temperature->The following preset ranges are met, and the air conditioning system is controlled to keep the current working mode:

wherein,a first preset threshold value.

In other embodiments, the air conditioning system is controlled to enter the oil return mode when the difference between the oil temperature and the oil return temperature is outside a preset range.

Illustratively, if the oil temperature isAnd oil return temperature->If the following preset range is not met, the controller controls the air conditioning system to enter an oil return mode:

wherein,a first preset threshold value.

In some embodiments, the controller controls the air conditioning system to enter the oil return mode, which is specifically implemented as: the controller controls the operating frequency of the compressor to rise to a first frequency and controls the compressor to operate at the first frequency for a first preset period of time.

In some examples, the setting of the first frequency is related to a capacity of the outdoor unit. Illustratively, the larger the outdoor unit capacity, the higher the first frequency.

In some embodiments, after the air conditioning system completes the oil return mode, the controller controls the air conditioning system again to perform steps S101 to S103 to determine whether the air conditioning system still lacks lubrication oil. And if the air conditioning system is still in the oil shortage device after the steps S101 to S103 are continuously executed for M times, controlling the air conditioning system to send out prompt information for prompting the air conditioning system that the oil return abnormality occurs. Wherein M is a positive integer greater than 2.

Alternatively, the air conditioning system itself may send out a prompt message. For example, the "ice blockage in air conditioning system" may be played in voice form, or the user may be prompted in the form of beeping, flashing signal lights, vibration, etc., which the embodiments of the present application are not limited to.

Alternatively, the air conditioning system may send a prompt message to the terminal device. For example, as shown in fig. 10, the controller 200 of the air conditioning system sends a prompt message to the terminal device 300, the prompt message is displayed on the terminal device interface in the form of a text popup window 305, and the text popup window 305 displays "system has ice blockage-! "literal information. In addition, when the terminal device displays the prompt information, the user may be prompted by text, voice, music, vibration, animation, and other modes, which is not limited in the embodiment of the present application.

In some embodiments, the air conditioning system turns on the oil return detection function by default; or, in response to an opening instruction of a user, controlling the air conditioning system to start an oil return detection function.

Further, in the case where the air conditioning system has turned on the oil return detection function, the controller performs the above steps S101 to S104.

In some embodiments, the above steps S101 to S104 are performed when the duration of time that the operating frequency of the compressor is less than the second frequency is longer than the second preset duration. It will be appreciated that if the duration of time that the operating frequency of the compressor is less than the second frequency is greater than the second predetermined duration, then this indicates that the compressor is continuously operating at too low a frequency and that there may be a lack of lubrication oil due to abnormal operation of the compressor. Therefore, the exhaust temperature of the compressor is obtained, and the oil temperature in the oil pool of the compressor is predicted according to the exhaust temperature, so that whether the compressor of the air conditioning system has the oil shortage phenomenon or not is further judged and judged.

The technical scheme provided by the embodiment of the application at least has the following beneficial effects: the air conditioning system predicts the oil temperature through the exhaust temperature, and judges whether the compressor needs oil return or not according to the relation between the oil return temperature of the compressor and the oil temperature. Therefore, an oil level sensor is not required to be additionally arranged in the compressor, and the cost is saved while the oil return control is realized.

It can be seen that the foregoing description of the solution provided by the embodiments of the present application has been presented mainly from a method perspective. To achieve the above-mentioned functions, embodiments of the present application provide corresponding hardware structures and/or software modules that perform the respective functions. Those of skill in the art will readily appreciate that the various illustrative modules and algorithm steps described in connection with the embodiments disclosed herein may be implemented as hardware or combinations of hardware and computer software. Whether a function is implemented as hardware or computer software driven hardware depends upon the particular application and design constraints imposed on the solution. Skilled artisans may implement the described functionality in varying ways for each particular application, but such implementation decisions should not be interpreted as causing a departure from the scope of the present application.

The embodiment of the application can divide the functional modules of the controller according to the method example, for example, each functional module can be divided corresponding to each function, and two or more functions can be integrated in one processing module. The integrated modules may be implemented in hardware or in software functional modules. Optionally, the division of the modules in the embodiment of the present application is schematic, which is merely a logic function division, and other division manners may be implemented in practice.

As shown in fig. 11, an embodiment of the present application provides a control apparatus for executing the control method of the air conditioning system. The control device 500 includes:

an acquisition module 501 for acquiring an exhaust temperature of an exhaust port of a compressor of an air conditioning system.

The processing module 502 is configured to predict an oil temperature in an oil sump of the compressor based on the discharge temperature.

The acquisition module 501 is further configured to acquire an oil return temperature after the first capillary tube between the compressor and the gas-liquid separator;

the processing module 502 is further configured to determine whether the air conditioning system enters the oil return mode according to a relationship between the oil return temperature and the oil temperature.

In some embodiments, the processing module 502 is specifically configured to: and when the difference value between the oil temperature and the oil return temperature is out of the preset range, controlling the air conditioning system to enter an oil return mode.

In some embodiments, the processing module 502 is specifically configured to: and when the difference between the oil temperature and the oil return temperature is within a preset range, controlling the air conditioning system to keep the current working mode.

In some embodiments, the processing module 502 is specifically configured to: and controlling the operation frequency of the compressor to be increased to a first frequency, and controlling the compressor to operate at the first frequency for a first preset time period.

In some embodiments, the processing module 502 is specifically configured to: and when the duration time that the operating frequency of the compressor is smaller than the second frequency is longer than the second preset duration time, predicting the oil temperature in the oil pool of the compressor according to the exhaust temperature.

The units in fig. 11 may also be referred to as modules, for example, the processing units may be referred to as processing modules.

The individual units in fig. 11 may be stored in a computer-readable storage medium if implemented in the form of software functional modules and sold or used as separate products. Based on such understanding, the technical solution of the embodiments of the present application may be essentially or a part contributing to the prior art or all or part of the technical solution may be embodied in the form of a software product stored in a storage medium, including several instructions to cause a computer device (which may be a personal computer, a server, or a network device, etc.) or a processor (processor) to perform all or part of the steps of the method described in the embodiments of the present application. The storage medium storing the computer software product includes: a U-disk, a removable hard disk, a read-only memory (ROM), a random access memory (random access memory, RAM), a magnetic disk, or an optical disk, or other various media capable of storing program codes.

The embodiment of the present application further provides a schematic hardware structure of a controller, as shown in fig. 12, where the controller 2000 includes a processor 2001, and optionally, a memory 2002 and a communication interface 2003 connected to the processor 2001. The processor 2001, memory 2002 and communication interface 2003 are connected by a bus 2004.

The processor 2001 may be a central processing unit (central processing unit, CPU), a general purpose processor network processor (network processor, NP), a digital signal processor (digital signal processing, DSP), a microprocessor, a microcontroller, a programmable logic device (programmable logic device, PLD), or any combination thereof. The processor 2001 may also be any other device with processing functionality, such as a circuit, a device or a software module. The processor 2001 may also include multiple CPUs, and the processor 2001 may be a single-core (single-CPU) processor or a multi-core (multi-CPU) processor. A processor herein may refer to one or more devices, circuits, or processing cores for processing data (e.g., computer program instructions).

Memory 2002 may be a read-only memory (ROM) or other type of static storage device that may store static information and instructions, a random access memory (random access memory, RAM) or other type of dynamic storage device that may store information and instructions, or an electrically erasable programmable read-only memory (electrically erasable programmable read-only memory, EEPROM), a compact disc read-only memory (compact disc read-only memory) or other optical disk storage, optical disk storage (including compact disc, laser disc, optical disc, digital versatile disc, blu-ray disc, etc.), magnetic disk storage media or other magnetic storage devices, or any other medium that can be used to carry or store desired program code in the form of instructions or data structures and that can be accessed by a computer, as embodiments of the application are not limited in this regard. The memory 2002 may be provided separately or may be integrated with the processor 2001. Wherein the memory 2002 may include computer program code. The processor 2001 is configured to execute computer program code stored in the memory 2002, thereby implementing the control method provided by the embodiment of the present application.

The communication interface 2003 may be used to communicate with other devices or communication networks (e.g., ethernet, radio access network (radio access network, RAN), wireless local area network (wireless local area networks, WLAN), etc. the communication interface 2003 may be a module, circuit, transceiver, or any means capable of enabling communications.

Bus 2004 may be a peripheral component interconnect standard (peripheral component interconnect, PCI) bus or an extended industry standard architecture (extended industry standard architecture, EISA) bus, among others. The bus 2004 may be divided into an address bus, a data bus, a control bus, and the like. For ease of illustration, only one thick line is shown in fig. 12, but not only one bus or one type of bus.

Embodiments of the present invention also provide a computer-readable storage medium including computer-executable instructions that, when executed on a computer, cause the computer to perform a method as provided in the above embodiments.

The embodiment of the present invention also provides a computer program product, which can be directly loaded into a memory and contains software codes, and the computer program product can implement the method provided by the above embodiment after being loaded and executed by a computer.

Those skilled in the art will appreciate that in one or more of the examples described above, the functions described in the present application may be implemented in hardware, software, firmware, or any combination thereof. When implemented in software, these functions may be stored on or transmitted over as one or more instructions or code on a computer-readable medium. Computer-readable media includes both computer storage media and communication media including any medium that facilitates transfer of a computer program from one place to another. A storage media may be any available media that can be accessed by a general purpose or special purpose computer.

From the foregoing description of the embodiments, it will be apparent to those skilled in the art that, for convenience and brevity of description, only the above-described division of functional modules is illustrated, and in practical application, the above-described functional allocation may be implemented by different functional modules according to needs, i.e. the internal structure of the apparatus is divided into different functional modules to implement all or part of the functions described above.

In the several embodiments provided by the present application, it should be understood that the disclosed apparatus and method may be implemented in other manners. For example, the above-described embodiments of the apparatus are merely illustrative, and the division of modules or units, for example, is merely a logical function division, and other manners of division are possible when actually implemented. For example, multiple modules or components may be combined or may be integrated into another device, or some features may be omitted, or not performed. Alternatively, the coupling or direct coupling or communication connection shown or discussed with each other may be an indirect coupling or communication connection via some interfaces, devices or modules, which may be in electrical, mechanical, or other forms. The modules illustrated as separate components may or may not be physically separate, and the components shown as modules may be one physical module or multiple physical modules, i.e., may be located in one place, or may be distributed across multiple different places. Some or all of the units may be selected according to actual needs to achieve the purpose of the solution of this embodiment.

In addition, each functional unit in the embodiments of the present application may be integrated in one processing unit, or each unit may exist alone physically, or two or more units may be integrated in one unit. The integrated units may be implemented in hardware or in software functional units. The integrated units, if implemented in the form of software functional units and sold or used as stand-alone products, may be stored in a readable storage medium. Based on such understanding, the technical solution of the embodiments of the present application may be essentially or a part contributing to the prior art or all or part of the technical solution may be embodied in the form of a software product stored in a storage medium, including several instructions for causing a device (may be a single-chip microcomputer, a chip or the like) or a processor (processor) to perform all or part of the steps of the method described in the embodiments of the present application. And the aforementioned storage medium includes: a usb disk, a removable hard disk, a ROM, a RAM, a magnetic disk, or an optical disk, etc.

The foregoing is merely illustrative of specific embodiments of the present application, and the scope of the present application is not limited thereto, but any changes or substitutions within the technical scope of the present application should be covered by the scope of the present application. Therefore, the protection scope of the present application should be subject to the protection scope of the claims.

Claims

1. An air conditioning system, comprising:

a refrigerant circulation loop for circulating the refrigerant in a loop formed by the compressor, the condenser, the electronic expansion valve, the evaporator, the four-way valve and the gas-liquid separator;

the compressor is used for compressing the low-temperature low-pressure refrigerant gas into high-temperature high-pressure refrigerant gas and discharging the high-temperature high-pressure refrigerant gas to the condenser;

an outdoor heat exchanger and an indoor heat exchanger, wherein one of the two heat exchangers works as a condenser and the other works as an evaporator;

a first temperature sensor for detecting an exhaust temperature of an exhaust port of the compressor;

the second temperature sensor is used for detecting the oil return temperature after the first capillary tube between the compressor and the gas-liquid separator;

a controller configured to:

acquiring the exhaust gas temperature by the first temperature sensor;

predicting the oil temperature in an oil sump of the compressor according to the exhaust temperature and a preset relation between the exhaust temperature and the oil temperature in the oil sump of the compressor; the preset relation between the exhaust temperature and the oil temperature is determined by a regression prediction model, and the regression prediction model is set by historical data and relation between the exhaust temperature and the oil temperature after pretreatment;

Acquiring the oil return temperature through the second temperature sensor;

and determining whether the air conditioning system enters an oil return mode according to the relation between the oil return temperature and the oil temperature.

2. The air conditioning system according to claim 1, wherein the exhaust gas temperature and the oil temperature satisfy the following correspondence relation:

wherein,is the exhaust temperature; />For the oil temperature; />And +.>Are all preset constants.

3. An air conditioning system according to claim 1, wherein,

the controller is configured to determine whether the air conditioning system enters an oil return mode according to the relation between the oil return temperature and the oil temperature, and specifically execute the following steps:

and when the difference value between the oil temperature and the oil return temperature is out of a preset range, controlling the air conditioning system to enter an oil return mode.

4. An air conditioning system according to claim 3, wherein,

the controller is configured to control the air conditioning system to enter an oil return mode, and specifically performs the following steps:

and controlling the operation frequency of the compressor to rise to a first frequency, and controlling the compressor to operate at the first frequency for a first preset period of time.

5. An air conditioning system according to any of claims 1 to 4, characterized in that,

the controller is configured to predict the oil temperature in the oil pool of the compressor according to the exhaust temperature, and specifically performs the following steps:

and when the duration time that the operating frequency of the compressor is smaller than the second frequency is longer than the second preset duration time, predicting the oil temperature in the oil pool of the compressor according to the exhaust temperature.

6. A control method of an air conditioning system, the method comprising:

acquiring an exhaust temperature of an exhaust port of a compressor of the air conditioning system;

acquiring the oil return temperature of a first capillary tube between a compressor of the air conditioning system and a gas-liquid separator;

7. The method of claim 6, wherein the exhaust gas temperature and the oil temperature satisfy the following correspondence:

8. The method of claim 6, wherein determining whether the air conditioning system enters an oil return mode based on the relationship between the oil return temperature and the oil temperature comprises:

9. The method of claim 8, wherein the controlling the air conditioning system to enter an oil return mode comprises:

10. The method according to any one of claims 6 to 9, wherein predicting the oil temperature in the oil sump of the compressor from the discharge temperature comprises: