WO2023279609A1 - 室外机回油控制方法 - Google Patents

室外机回油控制方法 Download PDF

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Publication number
WO2023279609A1
WO2023279609A1 PCT/CN2021/129798 CN2021129798W WO2023279609A1 WO 2023279609 A1 WO2023279609 A1 WO 2023279609A1 CN 2021129798 W CN2021129798 W CN 2021129798W WO 2023279609 A1 WO2023279609 A1 WO 2023279609A1
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Prior art keywords
oil return
ratio
outdoor unit
frequency
heat exchanger
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PCT/CN2021/129798
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English (en)
French (fr)
Inventor
罗荣邦
Original Assignee
青岛海尔空调器有限总公司
青岛海尔空调电子有限公司
海尔智家股份有限公司
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Publication of WO2023279609A1 publication Critical patent/WO2023279609A1/zh

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    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F24—HEATING; RANGES; VENTILATING
    • F24F—AIR-CONDITIONING; AIR-HUMIDIFICATION; VENTILATION; USE OF AIR CURRENTS FOR SCREENING
    • F24F11/00—Control or safety arrangements
    • F24F11/62—Control or safety arrangements characterised by the type of control or by internal processing, e.g. using fuzzy logic, adaptive control or estimation of values
    • F24F11/63—Electronic processing
    • F24F11/65—Electronic processing for selecting an operating mode
    • F24F11/67—Switching between heating and cooling modes
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F24—HEATING; RANGES; VENTILATING
    • F24F—AIR-CONDITIONING; AIR-HUMIDIFICATION; VENTILATION; USE OF AIR CURRENTS FOR SCREENING
    • F24F11/00—Control or safety arrangements
    • F24F11/50—Control or safety arrangements characterised by user interfaces or communication
    • F24F11/61—Control or safety arrangements characterised by user interfaces or communication using timers
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F24—HEATING; RANGES; VENTILATING
    • F24F—AIR-CONDITIONING; AIR-HUMIDIFICATION; VENTILATION; USE OF AIR CURRENTS FOR SCREENING
    • F24F11/00—Control or safety arrangements
    • F24F11/62—Control or safety arrangements characterised by the type of control or by internal processing, e.g. using fuzzy logic, adaptive control or estimation of values
    • F24F11/63—Electronic processing
    • F24F11/64—Electronic processing using pre-stored data
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F24—HEATING; RANGES; VENTILATING
    • F24F—AIR-CONDITIONING; AIR-HUMIDIFICATION; VENTILATION; USE OF AIR CURRENTS FOR SCREENING
    • F24F11/00—Control or safety arrangements
    • F24F11/70—Control systems characterised by their outputs; Constructional details thereof
    • F24F11/80—Control systems characterised by their outputs; Constructional details thereof for controlling the temperature of the supplied air
    • F24F11/83—Control systems characterised by their outputs; Constructional details thereof for controlling the temperature of the supplied air by controlling the supply of heat-exchange fluids to heat-exchangers
    • F24F11/84—Control systems characterised by their outputs; Constructional details thereof for controlling the temperature of the supplied air by controlling the supply of heat-exchange fluids to heat-exchangers using valves
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F24—HEATING; RANGES; VENTILATING
    • F24F—AIR-CONDITIONING; AIR-HUMIDIFICATION; VENTILATION; USE OF AIR CURRENTS FOR SCREENING
    • F24F11/00—Control or safety arrangements
    • F24F11/70—Control systems characterised by their outputs; Constructional details thereof
    • F24F11/80—Control systems characterised by their outputs; Constructional details thereof for controlling the temperature of the supplied air
    • F24F11/86—Control systems characterised by their outputs; Constructional details thereof for controlling the temperature of the supplied air by controlling compressors within refrigeration or heat pump circuits
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
    • F25B—REFRIGERATION MACHINES, PLANTS OR SYSTEMS; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS
    • F25B13/00—Compression machines, plants or systems, with reversible cycle
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
    • F25B—REFRIGERATION MACHINES, PLANTS OR SYSTEMS; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS
    • F25B31/00—Compressor arrangements
    • F25B31/002—Lubrication
    • F25B31/004—Lubrication oil recirculating arrangements
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
    • F25B—REFRIGERATION MACHINES, PLANTS OR SYSTEMS; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS
    • F25B41/00—Fluid-circulation arrangements
    • F25B41/30—Expansion means; Dispositions thereof
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
    • F25B—REFRIGERATION MACHINES, PLANTS OR SYSTEMS; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS
    • F25B43/00—Arrangements for separating or purifying gases or liquids; Arrangements for vaporising the residuum of liquid refrigerant, e.g. by heat
    • F25B43/02—Arrangements for separating or purifying gases or liquids; Arrangements for vaporising the residuum of liquid refrigerant, e.g. by heat for separating lubricants from the refrigerant
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F24—HEATING; RANGES; VENTILATING
    • F24F—AIR-CONDITIONING; AIR-HUMIDIFICATION; VENTILATION; USE OF AIR CURRENTS FOR SCREENING
    • F24F2140/00—Control inputs relating to system states
    • F24F2140/20—Heat-exchange fluid temperature

Definitions

  • the invention relates to the technical field of air conditioner oil return, in particular to an outdoor unit oil return control method.
  • refrigeration oil plays a vital role in the efficient operation of the compressor.
  • the refrigeration oil will participate in the cycle along with the refrigerant.
  • the current hairpin tube of the heat exchanger is an internally threaded copper tube, which affects the flow of the refrigerating machine oil, coupled with the centrifugal force of the refrigerant flow, resulting in partial freezing
  • the oil cannot return to the inside of the compressor in time, and stays on the inner wall of the threaded copper tube, which hinders the heat transfer between the refrigerant and the coil, reduces the heat transfer temperature difference, and makes the cooling and heating effect of the air conditioner worse.
  • problems such as insufficient lubrication of the compressor may also occur. Therefore, how to perform oil return operation on the outdoor heat exchanger has become a major concern of air conditioner manufacturers.
  • the application provides an oil return control method for the outdoor unit, which is applied to an air conditioner, and the air conditioner includes A compressor, a four-way valve, an outdoor heat exchanger, a throttling device, and an indoor heat exchanger connected to the road.
  • the indoor heat exchanger is provided with a first pressure sensor
  • the outdoor heat exchanger is provided with a second pressure sensor.
  • the air conditioner also includes a recovery pipeline, one end of the recovery pipeline communicates with the outlet of the outdoor heat exchanger, and the other end of the recovery pipeline communicates with the suction port of the compressor, so An on-off valve is arranged on the recovery pipeline, and the on-off valve is a normally closed valve.
  • control methods include:
  • the second preset duration is longer than the first preset duration.
  • the step of "selectively performing the outdoor unit oil return operation according to the judgment result" further includes:
  • the outdoor unit oil return operation is performed.
  • the step of "selectively performing the outdoor unit oil return operation according to the judgment result" further includes:
  • the first ratio is smaller than the first threshold and greater than or equal to a second threshold, then obtain the first operating frequency of the compressor;
  • the oil return operation of the outdoor unit is selectively performed.
  • the step of "selectively performing the outdoor unit oil return operation according to the judgment result" further includes:
  • the step of "selectively performing the outdoor unit oil return operation according to the judgment result" further includes:
  • control method further includes:
  • first operating frequency is greater than or equal to the first oil return frequency, further judge the magnitude of the first operating frequency and the second oil return frequency;
  • the outdoor unit oil return operation is performed.
  • the step of "selectively performing the outdoor unit oil return operation according to the judgment result" further includes:
  • the step of "selectively performing the outdoor unit oil return operation according to the judgment result" further includes:
  • the oil return operation of the outdoor unit is not performed, and the air conditioner is controlled to maintain the current operating state.
  • the step of "executing the outdoor unit oil return operation” further includes:
  • the on-off valve is controlled to open, and the throttling device is closed to a minimum opening.
  • control method further includes:
  • the indoor fan When the coil temperature of the indoor heat exchanger reaches the anti-cold wind temperature, the indoor fan is controlled to start running;
  • the on-off valve is controlled to be closed, and the throttling device is opened to a preset opening degree.
  • the air conditioner includes a compressor connected through a refrigerant pipeline, a four-way valve, an outdoor heat exchanger, a throttling device, and an indoor heat exchanger.
  • the air conditioner also includes a recovery pipeline, one end of the recovery pipeline communicates with the outlet of the outdoor heat exchanger, and the other end of the recovery pipeline communicates with the outlet of the compressor.
  • the suction port is connected, and there is an on-off valve on the recovery pipeline, which is a normally closed valve.
  • the control method includes: in the heating mode, when the continuous operation time of the air conditioner reaches the first preset time, calculate the indoor heat exchange rate.
  • the first high-low pressure ratio between the pressure of the air conditioner and the pressure of the outdoor heat exchanger when the continuous operation time of the air conditioner reaches the second preset time, calculate the pressure between the pressure of the indoor heat exchanger and the pressure of the outdoor heat exchanger the second high and low pressure ratio; determine the range of the first ratio between the second high and low pressure ratio and the first high and low pressure ratio; according to the judgment result, selectively perform the oil return operation of the outdoor unit; wherein, the second preset The duration is longer than the first preset duration.
  • the present application can realize the effective oil return of the outdoor unit, and ensure the lubrication effect of the compressor and the operation effect of the air conditioner. Specifically, by calculating the first high and low pressure ratio when the air conditioner's continuous operation time reaches the first preset time in heating mode, and the second high and low pressure ratio when it reaches the second preset time, and judging the second highest The range of the first ratio between the low pressure ratio and the first high and low pressure ratio, and then selectively perform the oil return operation of the outdoor unit based on the judgment result.
  • This application uses the high and low pressure ratio when the air conditioner is running to judge whether the outdoor unit needs Oil return operation, when the oil return operation is required, the oil return operation is performed on the outdoor unit, so that the refrigerating machine oil accumulated in the outdoor unit returns to the compressor in time, improving the heat exchange effect of the outdoor unit and improving the operation stability of the compressor.
  • Fig. 1 is the system diagram of the air conditioner of the present application in heating mode
  • Fig. 2 is the system diagram of the air conditioner of the present application in cooling mode
  • Fig. 3 is the flow chart of the outdoor unit oil return control method of the present application.
  • Fig. 4 is a logic diagram of a possible implementation process of the oil return control method for an outdoor unit of the present application.
  • connection should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; It can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediary, and it can be an internal communication between two components.
  • connection should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; It can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediary, and it can be an internal communication between two components.
  • FIG. 1 is a system diagram of the air conditioner of the present application in a heating mode.
  • the air conditioner includes a compressor 1 , a four-way valve 2 , an outdoor heat exchanger 3 , a throttling device 4 , an indoor heat exchanger 5 and a liquid accumulator 9 .
  • the exhaust port of the compressor 1 is connected with the P port of the four-way valve 2 through the refrigerant pipeline 6, and the E port of the four-way valve 2 is connected with the inlet of the indoor heat exchanger 5 through the refrigerant pipeline 6.
  • the outlet communicates with one port of the throttling device 4 through the refrigerant pipeline 6, and the other port of the throttling device 4 communicates with the inlet of the outdoor heat exchanger 3 through the refrigerant pipeline 6, and the outlet of the outdoor heat exchanger 3 passes through the refrigerant pipeline 6 is connected with the C port of the four-way valve 2, the S port of the four-way valve 2 is connected with the inlet of the accumulator 9 through the refrigerant pipeline 6, and the outlet of the accumulator 9 is connected with the suction port of the compressor 1 through the pipeline .
  • the throttling device 4 is preferably an electronic expansion valve, and a filter is provided in the liquid storage 9, and the liquid storage 9 can store refrigerant, separate gas and liquid of refrigerant, filter oil, eliminate noise, and buffer refrigerant.
  • the air conditioner also includes a recovery pipeline 7 and an on-off valve 8.
  • the recovery pipeline 7 adopts a copper tube with a smooth inner wall.
  • the on-off valve 8 is preferably a solenoid valve.
  • the solenoid valve is a normally closed valve and is arranged on the recovery pipeline 7.
  • the solenoid valve communicates with the controller of the air conditioner to receive the opening and closing signals issued by the controller.
  • the on-off valve 8 can also be an electronically controlled valve such as an electronic expansion valve.
  • the coil of the indoor heat exchanger 5 of the present application is further provided with a first pressure sensor 10 , and the first pressure sensor 10 is used to detect the pressure of the indoor heat exchanger 5 .
  • the coil of the outdoor heat exchanger 3 is also provided with a second pressure sensor 11 for detecting the pressure of the outdoor heat exchanger 3 .
  • the principle of detecting the pressure of the heat exchanger by the pressure sensor is common knowledge in the field, and will not be repeated here.
  • the oil return control method of the outdoor unit in this embodiment will be described in conjunction with the structure of the above-mentioned air conditioner, but those skilled in the art can understand that the specific structural composition of the air conditioner is not static and can be adjusted by those skilled in the art.
  • the accumulator 9 may be omitted, or other components may be added on the basis of the structure of the above-mentioned air conditioner.
  • FIG. 2 is a system diagram of the air conditioner of the present application in cooling mode
  • FIG. 3 is a flow chart of the oil return control method of the outdoor unit of the present application.
  • the flow direction of the refrigerant is: compressor ⁇ four-way valve ⁇ indoor heat exchanger ⁇ throttling device ⁇ outdoor heat exchanger ⁇ four-way valve ⁇ compressor.
  • the refrigerant is in the state of high temperature and high pressure in the indoor heat exchanger, and in the state of low temperature and low pressure in the outdoor heat exchanger, so it is easier to accumulate refrigeration oil in the outdoor heat exchanger.
  • the oil return control method of the outdoor unit of the present application includes:
  • the first preset duration can be any value between 30min-55min, preferably 45min in this application.
  • the first pressure sensor and the second pressure respectively detects the pressure of the indoor heat exchanger and the pressure of the outdoor heat exchanger, and then calculates a first high and low pressure ratio between the pressure of the indoor heat exchanger and the pressure of the outdoor heat exchanger.
  • the second preset duration is longer than the first preset duration, and the second preset duration can be any value between 60min-90min, preferably 75min in this application, and the air conditioner runs in heating mode for 45min After that, continue to run for another 30 minutes, that is, when the continuous running time reaches 75 minutes, detect the pressure of the indoor heat exchanger and the pressure of the outdoor heat exchanger through the first pressure sensor and the second pressure sensor respectively, and then calculate the pressure of the indoor heat exchanger The second high-low pressure ratio with the pressure of the outdoor heat exchanger.
  • S105 Determine the range of the first ratio between the second high-low pressure ratio and the first high-low pressure ratio.
  • the first ratio is compared with the first threshold and the second threshold to determine the range of the first ratio.
  • the first threshold is greater than the second threshold.
  • the first threshold may be any value in the range of 1.3-1.6
  • the second threshold may be any value in the range of 1.05-1.3.
  • the step of "selectively performing the oil return operation of the outdoor unit according to the judgment result" specifically includes:
  • the oil return operation of the outdoor unit is performed.
  • the first ratio is greater than or equal to the first threshold, it proves that the high and low pressure ratio increases greatly when the air conditioner is in continuous heating operation, that is, the refrigerating machine oil in the outdoor heat exchanger accumulates more, resulting in an increase in the high and low pressure of the air conditioner.
  • the air conditioner If the first ratio is smaller than the second threshold, the oil return operation of the outdoor unit is not performed, and the air conditioner is controlled to maintain the current operating state.
  • the first ratio is smaller than the second threshold, it proves that the high and low pressure ratio does not change much during the continuous heating operation of the air conditioner, the air conditioner operates relatively stably, and the oil return is normal. At this time, there is no need to perform the oil return operation of the outdoor unit, and the air conditioner is controlled to maintain the current running state.
  • the first ratio is less than the first threshold and greater than or equal to the second threshold, obtain the first operating frequency of the compressor; determine the magnitude of the first operating frequency and the first oil return frequency.
  • the first ratio is less than the first threshold and greater than or equal to the second threshold, it proves that the high and low pressure ratio of the air conditioner has a certain increase during continuous heating operation, and the refrigerating machine oil in the outdoor heat exchanger has a certain accumulation.
  • the compressor when the compressor continues to run for a third preset time at the first oil return frequency, calculate the third high and low pressure ratio between the pressure of the indoor heat exchanger and the pressure of the outdoor heat exchanger; determine the third high and low pressure ratio The range of the second ratio between the second high and low pressure ratio; if the second ratio is less than the first threshold and greater than or equal to the second threshold, control the compressor to increase the frequency to run at the second oil return frequency; if the second ratio If the value is less than the second threshold, the air conditioner is controlled to maintain the current operating state until the ratio between the calculated high and low pressure ratios is greater than or equal to the first threshold before performing the oil return operation of the outdoor unit.
  • the third preset duration can be any value from 5min to 20min. In this application, 10min is used.
  • the compressor continues to run at the first oil return frequency for 10 minutes, a good oil return effect has been achieved theoretically.
  • the compressor is controlled to continue to increase the frequency to the second oil return frequency. Oil return to the air conditioner with a higher oil return frequency.
  • the second ratio is less than the second threshold, it proves that the high and low pressure ratio of the air conditioner has dropped, which has a certain oil return effect.
  • the priority is to ensure the comfort of the indoor environment, and the air conditioner is controlled to maintain the current operating state and continue to run.
  • the oil return operation of the outdoor unit is not performed until the ratio between the high and low pressure ratios calculated twice successively is greater than or equal to the first threshold.
  • the interval between calculating the high-low pressure ratio twice successively can be set arbitrarily, such as 10 minutes or 20 minutes.
  • the air conditioner is controlled to take the current set temperature as the target temperature to control the air conditioner to continue running.
  • the high and low pressure ratio between the pressure of the indoor heat exchanger and the pressure of the outdoor heat exchanger is obtained every 10 minutes. After obtaining at least two high and low pressure ratios continuously, calculate the ratio between the two high and low pressure ratios, and compare the ratio with the first threshold, until the ratio is greater than or equal to the first threshold, directly execute the oil return operation.
  • the compressor when the compressor continues to run for a fourth preset time at the second oil return frequency, calculate the fourth high and low pressure ratio between the pressure of the indoor heat exchanger and the pressure of the outdoor heat exchanger; determine the fourth high and low pressure ratio The range of the third ratio between the third high and low pressure ratio; if the third ratio is less than the first threshold and greater than or equal to the second threshold, perform the oil return operation of the outdoor unit; if the third ratio is less than the second threshold, then The air conditioner is controlled to maintain the current running state until the ratio between the high and low pressure ratios calculated twice successively is greater than or equal to the first threshold before performing the oil return operation of the outdoor unit.
  • the fourth preset duration can be any value from 5min to 20min. In this application, 10min is used.
  • 10min is used.
  • the compressor continues to run for 10min at the second oil return frequency, a good oil return effect has been achieved theoretically.
  • the machine performs forced oil return.
  • the priority is to ensure the comfort of the indoor environment, and the air conditioner is controlled to maintain the current operating state and continue to run.
  • the oil return operation of the outdoor unit is not performed until the ratio between the high and low pressure ratios calculated twice successively is greater than or equal to the first threshold.
  • the steps of "controlling the air conditioner to maintain the current operating state and continue to operate until the ratio between the high and low pressure ratios calculated twice successively is greater than or equal to the first threshold before performing the oil return operation of the outdoor unit" are similar to the aforementioned control process, I won't repeat them here.
  • the compressor when the compressor continues to run for the fifth preset time at the second oil return frequency, calculate the fifth high and low pressure ratio between the pressure of the indoor heat exchanger and the pressure of the outdoor heat exchanger; determine the fifth high and low pressure ratio The range of the fourth ratio between the second high and low pressure ratio; if the fourth ratio is less than the first threshold and greater than or equal to the second threshold, perform the oil return operation of the outdoor unit; if the fourth ratio is less than the second threshold, then The air conditioner is controlled to maintain the current running state until the ratio between the high and low pressure ratios calculated twice successively is greater than or equal to the first threshold before performing the oil return operation of the outdoor unit.
  • the fifth preset duration can be any value from 5min to 20min. In this application, 10min is used.
  • 10min is used.
  • the fourth ratio is less than the second threshold, it proves that the high and low pressure ratio of the air conditioner has dropped, which has a certain oil return effect.
  • the priority is to ensure the comfort of the indoor environment, and the air conditioner is controlled to maintain the current operating state and continue to run.
  • the oil return operation of the outdoor unit is not performed until the ratio between the high and low pressure ratios calculated twice successively is greater than or equal to the first threshold.
  • the steps of "controlling the air conditioner to maintain the current operating state and continue to operate until the ratio between the high and low pressure ratios calculated twice successively is greater than or equal to the first threshold before performing the oil return operation of the outdoor unit" are similar to the aforementioned control process, I won't repeat them here.
  • the step of "performing the oil return operation of the outdoor unit" further includes:
  • the normal operating frequency of the compressor is relatively high, and the four-way valve cannot perform reversing. Therefore, when the air conditioner starts to perform the oil return operation of the outdoor unit, firstly, the compressor is lowered from the normal operating frequency to the first reversing frequency that allows the four-way valve to reversing, so that the four-way valve can be reversing and converted to refrigeration. model.
  • the air conditioner After the four-way valve is reversed, the air conditioner operates in cooling mode. If the indoor unit continues to supply air, it will blow cold air to the room, which will bring a bad experience to the user. At this time, control the indoor fan to run for the sixth preset time to blow out the waste heat, and then stop running to avoid the cooling of the air and affect the user experience.
  • the sixth preset duration may be any value in 10s-1min, and may be 30s in this application.
  • the frequency of the compressor is controlled to increase to the third oil return frequency.
  • the third oil return frequency may be the highest frequency of the compressor. At this frequency, the compressor can increase the temperature and pressure of the refrigerant in the shortest time, thereby improving the oil return effect.
  • the control on-off valve When the operating mode is switched to refrigeration mode, the control on-off valve is opened and the throttling device is closed to the minimum opening. Control the throttling device to close to the minimum opening degree, that is, the state where the opening degree is 0, the throttling device realizes complete throttling, and the refrigerant cannot flow through.
  • the high-temperature and high-pressure refrigerant discharged from the compressor flows through the outdoor heat exchanger, and the high-temperature and high-pressure refrigerant quickly impacts the coil of the outdoor heat exchanger, and the refrigerating machine oil inside the coil is driven by the high-temperature refrigerant
  • the recovery of the engine oil is realized by returning to the reservoir through the recovery line.
  • the control method further includes: after the on-off valve is opened for the seventh preset time period, controlling The frequency of the compressor is reduced to the second reversing frequency; the reversing of the four-way valve is controlled to switch to the heating mode; when the coil temperature of the indoor heat exchanger reaches the anti-cold air temperature, the indoor fan is controlled to start running; based on the set temperature The second operating frequency is determined, and the compressor is controlled to operate according to the second operating frequency; the on-off valve is controlled to be closed, and the throttling device is opened to a preset opening degree.
  • the seventh preset duration can be any value in 5min-15min, and in this application, it is preferably 10min.
  • the on-off valve is opened and the throttling device is closed for 10 minutes, the high-temperature and high-pressure refrigerant has circulated many times, which is enough to produce a better oil return effect. Therefore, when the on-off valve is opened and the throttling device is closed for 10 minutes, it can exit the outdoor Engine oil return operation.
  • the air conditioner needs to return to the operating mode before entering the oil return operation, so as to continue to adjust the indoor temperature.
  • the compressor is controlled to decrease from the current operating frequency to a second reversing frequency that allows the four-way valve to reversing, so that the four-way valve can be reversing and converted into a heating mode.
  • the indoor fan is controlled to start running.
  • the indoor fan can no longer blow cold air outside, so the indoor fan can be controlled to start and run to meet the heating demand of the user.
  • the second operating frequency of the compressor is determined, and then the compressor is controlled to operate at the second operating frequency.
  • the on-off valve is controlled to be closed, and the throttling device is adjusted to a preset opening degree.
  • the preset opening degree is the maximum opening degree of the throttling device. Control the throttling device to maintain the maximum opening, because the refrigerant circulates between the compressor and the outdoor heat exchanger during the oil return operation of the outdoor unit, resulting in the lack of refrigerant in the indoor heat exchanger, so the throttling device maintains the maximum opening, so that the refrigerant Fill the indoor heat exchanger quickly to realize the normal circulation of the refrigerant as soon as possible.
  • the way of exiting the oil return operation of the outdoor unit is not limited to the above one, and those skilled in the art can freely choose a specific control mode on the premise that the air conditioner can be restored to the operating state before entering the oil return operation of the outdoor unit.
  • This choice does not depart from the principles of the present application.
  • the air deflector of the indoor unit can send air upwards, so as to prevent the user from causing bad use due to the low temperature of the indoor heat exchanger coil when the air conditioner just switches to heating mode. experience.
  • the rapid flow of high-temperature and high-pressure refrigerant can be used to impact the inside of the coil of the outdoor heat exchanger, so that the refrigerating machine oil
  • the refrigerant is directly returned to the inside of the accumulator through the recovery pipeline to achieve efficient oil return.
  • the application can use the recovery pipeline to recover the refrigerating machine oil during the oil return operation of the outdoor unit, so that after the high-temperature and high-pressure refrigerant flushes the outdoor heat exchanger, Instead of going through the internal and external heat exchangers again, the refrigeration oil is directly brought back to the liquid receiver for recovery, which reduces the flow of high-temperature refrigerant, reduces the pressure drop along the way, and improves the oil return effect of the outdoor unit.
  • the above embodiment is described in conjunction with the comparison between the first ratio and the first threshold and the second threshold, it is obvious that those skilled in the art can adjust the number of thresholds. without departing from the principles of the application.
  • the first ratio is only compared with one threshold, or compared with three or four thresholds, and so on.
  • the specific operations in the above-mentioned embodiment when the first ratio is less than the first threshold and greater than or equal to the second threshold are not static, and those skilled in the art can Make adjustments, such adjustments include but are not limited to adjustments to the quantity of oil return frequency, adjustments to preset duration, adjustments to deletion of steps in some intermediate processes, etc.
  • FIG. 4 is a logic diagram of a possible implementation process of the oil return control method of the outdoor unit of the present application.
  • step S201 is executed.
  • step S203 is executed.
  • step S205 is executed to calculate K2/K1 and determine whether K2/K1 ⁇ 1.5 holds true.
  • step S231 is executed; otherwise, when the judgment result is not established, step S207 is executed.
  • step S207 further determining whether K2/K1 ⁇ 1.1 is established.
  • step S209 is executed; otherwise, when the judgment result is not established, step S211 is executed.
  • step S211 Obtain the operating frequency f of the compressor and determine whether the operating frequency f ⁇ f1 holds true.
  • step S213 is executed; otherwise, when the judgment result is not established, step S221 is executed.
  • step S215 is executed to calculate K3/K2 and determine whether 1.1 ⁇ K3/K2 ⁇ 1.5 holds true.
  • step S217 is executed; otherwise, when the judgment result is not established, step S227 is executed.
  • step S219 is executed to calculate K4/K3 and determine whether 1.1 ⁇ K4/K3 ⁇ 1.5 holds true.
  • step S231 is executed; otherwise, when the judgment result is false, step S227 is executed.
  • step S225 is executed to calculate K5/K2 and determine whether 1.1 ⁇ K5/K2 ⁇ 1.5 holds true.
  • step S231 is executed; otherwise, when the judgment result is false, step S227 is executed.
  • the above air conditioner also includes some other known structures, such as a processor, a controller, a memory, etc.
  • the memory includes but not limited to random access memory, flash memory, read-only memory, programmable read-only memory, Volatile memory, non-volatile memory, serial memory, parallel memory or registers, etc.
  • processors include but not limited to CPLD/FPGA, DSP, ARM processors, MIPS processors, etc.

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Abstract

本发明涉及空调回油技术领域，具体涉及一种室外机回油控制方法。本申请旨在解决如何保证室外机回油的问题。为此目的，本申请的空调器包括回收管路，其一端与室外换热器进口连通，另一端与压缩机吸气口连通，回收管路上设有通断阀。控制方法包括：制热模式下，当空调器的持续运行时长达到第一预设时长时，计算室内换热器的压力与室外换热器的压力的第一高低压比；当空调器的持续运行时长达到第二预设时长时，计算室内换热器的压力与室外换热器的压力的第二高低压比；判断第二高低压比与第一高低压比的第一比值所处的范围；根据判断结果，选择性地执行室外机回油操作。本申请能够实现室外机的有效回油，保证压缩机润滑效果和空调运行效果。

Description

室外机回油控制方法 技术领域
本发明涉及空调回油技术领域，具体涉及一种室外机回油控制方法。
背景技术
冷冻机油作为压缩机的润滑剂，对压缩机的高效运行起着至关重要的作用。在空调系统的冷媒循环过程中，冷冻机油会跟随冷媒一起参与循环。
制热情况下，当冷冻机油跟随冷媒循环至室外换热器时，由于目前换热器的发卡管为内螺纹铜管，影响冷冻机油的流动，再加上冷媒流动的离心力作用，导致部分冷冻机油不能及时返回压缩机内部，停留在螺纹状的铜管内壁，阻碍了冷媒与盘管之间的传热，降低了传热温差，使空调制冷制热效果变差。同时，由于部分冷冻机油没有及时回到压缩机内部，还会导致压缩机润滑不充分等问题出现。因此，如何对室外换热器进行回油操作成为空调厂家重点关注的问题。
相应地，本领域需要一种新的室外机回油控制方法来解决上述问题。
发明内容
为了解决现有技术中的上述至少一个问题，即为了解决如何保证室外机回油的问题，本申请提供了一种室外机回油控制方法，应用于空调器，所述空调器包括通过冷媒管路连接的压缩机、四通阀、室外换热器、节流装置、室内换热器，所述室内换热器上设置有第一压力传感器，所述室外换热器上设置有第二压力传感器，所述空调器还包括回收管路，所述回收管路的一端与所述室外换热器的出口连通，所述回收管路的另一端与所述压缩机的吸气口连通，所述回收管路上设置有通断阀，所述通断阀为常闭阀，
所述控制方法包括：
制热模式下，当所述空调器的持续运行时长达到第一预设时长时，计算所述室内换热器的压力与所述室外换热器的压力之间的第一高低压比；
当所述空调器的持续运行时长达到第二预设时长时，计算所述室内换热器的压力与所述室外换热器的压力之间的第二高低压比；
判断所述第二高低压比与所述第一高低压比之间的第一比值所处的范围；
根据判断结果，选择性地执行室外机回油操作；
其中，所述第二预设时长大于所述第一预设时长。
在上述室外机回油控制方法的优选技术方案中，“根据判断结果，选择性地执行室外机回油操作”的步骤进一步包括：
如果所述第一比值大于等于第一阈值，则执行所述室外机回油操作。
在上述室外机回油控制方法的优选技术方案中，“根据判断结果，选择性地执行室外机回油操作”的步骤进一步包括：
如果所述第一比值小于所述第一阈值且大于等于第二阈值，则获取所述压缩机的第一运行频率；
判断所述第一运行频率与第一回油频率的大小；
如果所述第一运行频率小于所述第一回油频率，则控制所述压缩机升频至所述第一回油频率运行；
当所述压缩机以所述第一回油频率持续运行第三预设时长时，计算所述室内换热器的压力与所述室外换热器的压力之间的第三高低压比；
判断所述第三高低压比与所述第二高低压比之间的第二比值所处的范围；
根据判断结果，选择性地执行所述室外机回油操作。
在上述室外机回油控制方法的优选技术方案中，“根据判断结果，选择性地执行所述室外机回油操作”的步骤进一步包括：
如果所述第二比值小于所述第一阈值且大于等于所述第二阈值，则控制所述压缩机升频至第二回油频率运行；
当所述压缩机以所述第二回油频率持续运行第四预设时长时，计算所述室内换热器的压力与所述室外换热器的压力之间的第四高低压比；
判断所述第四高低压比与所述第三高低压比之间的第三比值所处的范围；
根据判断结果，选择性地执行所述室外机回油操作；并且/或者
如果所述第二比值小于所述第二阈值，则控制所述空调器保持当前运行状态，直至先后两次计算出的高低压比之间的比值大于所述第一阈值时再执行所述室外机回油操作。
在上述室外机回油控制方法的优选技术方案中，“根据判断结果，选择性地执行所述室外机回油操作”的步骤进一步包括：
如果所述第三比值小于所述第一阈值且大于等于所述第二阈值，则执行所述室外机回油操作；并且/或者
如果所述第三比值小于所述第二阈值，则控制所述空调器保持当前运行状态，直至先后两次计算出的高低压比之间的比值大于所述第一阈值时再执行所述室外机回油操作。
在上述室外机回油控制方法的优选技术方案中，所述控制方法还包括：
如果所述第一运行频率大于等于所述第一回油频率，则进一步判断所述第一运行频率与所述第二回油频率的大小；
如果所述第一运行频率小于所述第二回油频率，则控制所述压缩机升频至第二回油频率运行；
当所述压缩机以所述第二回油频率持续运行第五预设时长时，计算所述室内换热器的压力与所述室外换热器的压力之间的第五高低压比；
判断所述第五高低压比与所述第二高低压比之间的第四比值所处的范围；
根据判断结果，选择性地执行所述室外机回油操作；并且/或者
如果所述第一运行频率大于等于所述第二回油频率，则执行所述室外机回油操作。
在上述室外机回油控制方法的优选技术方案中，“根据判断结果，选择性地执行所述室外机回油操作”的步骤进一步包括：
如果所述第四比值小于所述第一阈值且大于等于所述第二阈值，则执行所述室外机回油操作；并且/或者
如果所述第四比值小于所述第二阈值，则控制所述空调器保持当前运行状态，直至先后两次计算出的高低压比之间的比值大于所述第一阈值时再执行所述室外机回油操作。
在上述室外机回油控制方法的优选技术方案中，“根据判断结果，选择性地执行室外机回油操作”的步骤进一步包括：
如果所述第一比值小于第二阈值，则不执行所述室外机回油操作，控制所述空调器保持当前运行状态。
在上述室外机回油控制方法的优选技术方案中，“执行室外机回油操作”的步骤进一步包括：
控制所述压缩机降频至第一换向频率；
控制所述四通阀换向，以转换成制冷模式；
在所述四通阀换向后，控制室内风机继续运行第六预设时长后关闭；
控制所述压缩机升频至第三回油频率；
控制所述通断阀打开、所述节流装置关闭至最小开度。
在上述室外机回油控制方法的优选技术方案中，在“控制所述通断阀打开、所述节流装置关闭至最小开度”的步骤之后，所述控制方法还包括：
在所述通断阀打开并持续第第七预设时长后，控制所述压缩机降频至第二换向频率；
控制所述四通阀换向，以转换成制热模式；
当所述室内换热器的盘管温度达到防冷风温度时，控制所述室内风机启动运行；
基于设定温度确定第二运行频率，并控制所述压缩机按照所述第二运行频率运行；
控制所述通断阀关闭，所述节流装置打开至预设开度。
需要说明的是，在本申请的优选技术方案中，空调器包括通过冷媒管路连接的压缩机、四通阀、室外换热器、节流装置、室内换热器，室内换热器上设置有第一压力传感器，室外换热器上设置有第二压力传感器，空调器还包括回收管路，回收管路的一端与室外换热器的出口连通，回收管路的另一端与压缩机的吸气口连通，回收管路上设置有通断阀，通断阀为常闭阀，控制方法包括：制热模式下，当空调器的持续运行时长达到第一预设时长时，计算室内换热器的压力与室外换热器的压力之间的第一高低压比；当空调器的持续运行时长达到第二预设时长时，计算室内换热器的压力与室外换热器的压力之间的第二高低压比；判断第二高低压比与第一高低压比之间的第一比值所处的范围；根据判断结果，选择性地执行室外机回油操作；其中，第二预设时长大于第一预设时长。
通过上述控制方式，本申请能够实现室外机的有效回油，保证压缩机润滑效果和空调运行效果。具体而言，通过在制热模式下计算空调器 的持续运行时长达到第一预设时长时的第一高低压比，以及达到第二预设时长的第二高低压比，并判断第二高低压比与第一高低压比之间的第一比值所处的范围，然后基于判断结果选择性地执行室外机回油操作，本申请利用空调器运行时的高低压比来判断室外机是否需要回油操作，当需要回油操作时对室外机执行回油操作，使得室外机内积存的冷冻机油及时回到压缩机中，提高室外机的换热效果，提高压缩机运行稳定性。
附图说明
下面参照附图来描述本申请的室外机回油控制方法。附图中：
图1为本申请的空调器在制热模式下的系统图；
图2为本申请的空调器在制冷模式下的系统图；
图3为本申请的室外机回油控制方法的流程图；
图4为本申请的室外机回油控制方法的一种可能的实施过程的逻辑图。
附图标记列表
1、压缩机；2、四通阀；3、室外换热器；4、节流装置；5、室内换热器；6、冷媒管路；7、回收管路；8、通断阀；9、储液器；10、第一压力传感器；11、第二压力传感器。
具体实施方式
下面参照附图来描述本申请的优选实施方式。本领域技术人员应当理解的是，这些实施方式仅仅用于解释本申请的技术原理，并非旨在限制本申请的保护范围。例如，尽管下文详细描述了本申请方法的详细步骤，但是，在不偏离本申请的基本原理的前提下，本领域技术人员可以对上述步骤进行组合、拆分及调换顺序，如此修改后的技术方案并没有改变本申请的基本构思，因此也落入本申请的保护范围之内。
需要说明的是，在本申请的描述中，术语“第一”、“第二”、“第三”、“第四”、“第五”、“第六”、“第七”、“第八”仅用于描述目的，而不能理解为指示或暗示相对重要性。
还需要说明的是，在本申请的描述中，除非另有明确的规定和限定，术语“连接”应做广义理解，例如，可以是固定连接，也可以是可拆卸连接，或一体地连接；可以是机械连接，也可以是电连接；可以是直接相连， 也可以通过中间媒介间接相连，可以是两个元件内部的连通。对于本领域技术人员而言，可根据具体情况理解上述术语在本申请中的具体含义。
首先参照图1，对本申请的空调器的结构进行描述。其中，图1为本申请的空调器在制热模式下的系统图。
如图1所示，在一种可能的实施方式中，空调器包括压缩机1、四通阀2、室外换热器3、节流装置4、室内换热器5和储液器9。压缩机1的排气口通过冷媒管路6与四通阀2的P接口连通，四通阀2的E接口通过冷媒管路6与室内换热器5的进口连通，室内换热器5的出口通过冷媒管路6与节流装置4的一端口连通，节流装置4的另一端口通过冷媒管路6与室外换热器3的进口连通，室外换热器3的出口通过冷媒管路6与四通阀2的C接口连通，四通阀2的S接口通过冷媒管路6与储液器9的进口连通，储液器9的出口通过管路与压缩机1的吸气口连通。节流装置4优选地为电子膨胀阀，储液器9内设置有过滤网，储液器9能够起到贮藏冷媒、冷媒气液分离、油污过滤、消音和冷媒缓冲等作用。
空调器还包括回收管路7和通断阀8，回收管路7采用内壁光滑的铜管，该铜管的第一端设置在节流装置4与室外换热器3的进口之间的冷媒管路6上，铜管的第二端设置在四通阀2的S接口与储液器9的进口之间的冷媒管路6上。通断阀8优选地为电磁阀，电磁阀为常闭阀且设置在回收管路7上，该电磁阀与空调器的控制器通信连接，以接收控制器下发的开启和关闭信号。当然，通断阀8也可以选择电子膨胀阀等电控阀。
为实现下述方法，本申请的室内换热器5的盘管上还设置有第一压力传感器10，第一压力传感器10用于检测室内换热器5的压力。室外换热器3的盘管上还设置有第二压力传感器11，第二压力传感器11用于检测室外换热器3的压力。通过压力传感器检测换热器的压力的原理本领域公知常识，在此不再赘述。
以下本实施例的室外机回油控制方法将结合上述空调器的结构进行描述，但本领域技术人员可以理解的是，空调器的具体结构组成并非一成不变，本领域技术人员可以对其进行调整，例如，储液器9可以省略，或者在上述空调器的结构的基础上增加其他部件等。
下面结合图1、图2和图3，对本申请的室外机回油控制方法进行介绍。其中，图2为本申请的空调器在制冷模式下的系统图；图3为本申请的室外机回油控制方法的流程图。
如图1所示，当空调器运行制热模式时，冷媒的流向为：压缩机→四通阀→室内换热器→节流装置→室外换热器→四通阀→压缩机。其中，冷媒在室内换热器中为高温高压状态，在室外换热器中为低温低压状态，因此室外换热器中更容易积攒冷冻机油。
如图3所示，为了解决如何保证室外机回油的问题，本申请的室外机回油控制方法包括：
S101、制热模式下，当空调器的持续运行时长达到第一预设时长时，计算室内换热器的压力与室外换热器的压力之间的第一高低压比。
一种可能的实施方式中，第一预设时长可以为30min-55min中的任意值，本申请优选为45min，在空调器以制热模式持续运行45min时，通过第一压力传感器和第二压力传感器分别检测室内换热器的压力和室外换热器的压力，然后计算室内换热器的压力与室外换热器的压力之间的第一高低压比。
S103、当空调器的持续运行时长达到第二预设时长时，计算室内换热器的压力与室外换热器的压力之间的第二高低压比。
一种可能的实施方式中，第二预设时长大于第一预设时长，第二预设时长可以为60min-90min中的任意值，本申请优选为75min，在空调器以制热模式运行45min之后，再继续运行30min、即持续运行时长达到75min时，再次通过第一压力传感器和第二压力传感器分别检测室内换热器的压力和室外换热器的压力，然后计算室内换热器的压力与室外换热器的压力之间的第二高低压比。
S105、判断第二高低压比与第一高低压比之间的第一比值所处的范围。
一种可能的实施方式中，在获得第一高低压比与第二高低压比后，计算第二高低压比与第一高低压比之间的第一比值，并判断该第一比值所处的范围。其中，本申请中将第一比值与第一阈值和第二阈值进行比较，判断第一比值所处的范围。其中第一阈值大于第二阈值。本申请中，第一阈值可以为1.3-1.6中的任意值，第二阈值可以为1.05-1.3中的任意值。
S107、根据判断结果，选择性地执行室外机回油操作。
一种可能的实施方式中，“根据判断结果，选择性地执行室外机回油操作”的步骤具体包括：
(1)如果第一比值大于等于第一阈值，则执行室外机回油操作。当第一比值大于等于第一阈值时，证明空调器在持续制热运行时高低压比上升幅度较大，也即室外换热器内的冷冻机油积存较多，导致空调器的高低压力上升。此时需要立即执行室外机回油操作，以使得室外机中积存的冷冻机油回流至压缩机中。
(2)如果第一比值小于第二阈值，则不执行室外机回油操作，控制空调器保持当前运行状态。当第一比值小于第二阈值时，则证明空调器在持续制热运行时高低压比变化不大，空调器运行较为稳定，回油正常。此时无需执行室外机回油操作，控制空调器保持当前运行状态。
(3)如果第一比值小于第一阈值且大于等于第二阈值，则获取压缩机的第一运行频率；判断第一运行频率与第一回油频率的大小。当第一比值小于第一阈值且大于等于第二阈值时，证明空调器在持续制热运行时高低压比有一定上升，室外换热器内的冷冻机油有一定积存。但又由于下述的室外机回油操作会暂时切换空调器的运行模式，终止对室内空气的调节，对用户体验有较大影响，因此在第一比值小于第一阈值且大于等于第二阈值时，先获取压缩机的第一运行频率，基于第一运行频率与第一回油频率和第二回油频率的大小确定如何操作。具体地：
(3a)如果第一运行频率小于第一回油频率，则控制压缩机升频至第一回油频率运行。现有技术中，为保证冷冻机油顺利回流至压缩机，通常都设置有回油频率，当空调器运行在回油频率时，冷冻机油能够较好地回流至压缩机。本申请利用该技术手段，当第一运行频率小于第一回油频率时，先控制压缩机升频至第一回油频率运行，以期在不改变空调器的运行模式的前提下，使冷冻机油能够顺利回流至压缩机。
进一步地，当压缩机以第一回油频率持续运行第三预设时长时，计算室内换热器的压力与室外换热器的压力之间的第三高低压比；判断第三高低压比与第二高低压比之间的第二比值所处的范围；如果第二比值小于第一阈值且大于等于第二阈值，则控制压缩机升频至第二回油频率运行；如果第二比值小于第二阈值，则控制空调器保持当前运行状态， 直至先后两次计算出的高低压比之间的比值大于等于第一阈值时再执行室外机回油操作。
具体地，第三预设时长可以为5min-20min中的任意值，本申请中取10min，当压缩机以第一回油频率持续运行10min时，理论上已经达到较好的回油效果，此时再次计算室内换热器的压力与室外换热器的压力之间的第三高低压比，并判断第三高低压比与第二高低压之间的第二比值所处的范围，来验证回油效果。如果第二比值仍处于第一阈值与第二阈值之间，证明当前回油效果较差，空调器的高低压比仍在上升，此时控制压缩机继续升频至第二回油频率运行，以更高的回油频率对空调器进行回油。当第二比值小于第二阈值时，证明空调器的高低压比有所回落，起到一定的回油效果，此时优先保证室内环境的舒适度，控制空调器保持当前的运行状态继续运行，直至先后两次计算出的高低压比之间的比值大于等于第一阈值时再执行室外机回油操作。其中，先后两次计算高低压比的间隔可以任意设定，如10min或20min等。
举例而言，在第二比值小于第二阈值时，控制空调器以当前的设定温度为目标温度控制空调器继续运行，运行过程中可以调节压缩机频率、节流装置开度、室内外风机风速等。并且，在继续运行过程中，每隔10min获取室内换热器的压力与室外换热器的压力之间的高低压比。在连续获取至少两个高低压比之后，计算两个高低压比之间的比值，并将比值与第一阈值进行比较，直至该比值大于等于第一阈值时，直接执行回油操作。
进一步地，当压缩机以第二回油频率持续运行第四预设时长时，计算室内换热器的压力与室外换热器的压力之间的第四高低压比；判断第四高低压比与第三高低压比之间的第三比值所处的范围；如果第三比值小于第一阈值且大于等于第二阈值，则执行室外机回油操作；如果第三比值小于第二阈值，则控制空调器保持当前运行状态，直至先后两次计算出的高低压比之间的比值大于等于第一阈值时再执行室外机回油操作。
具体地，第四预设时长可以为5min-20min中的任意值，本申请中取10min，当压缩机以第二回油频率持续运行10min时，理论上已经达到较好的回油效果，此时再次计算室内换热器的压力与室外换热器的压力之间的第四高低压比，并判断第四高低压比与第三高低压之间的第三比值所处的范围，来验证回油效果。如果第三比值仍处于第一阈值与第二阈 值之间，证明当前回油效果较差，空调器的高低压比仍在上升，此时控制压缩机直接执行室外机回油操作，以对室外机进行强制回油。当第三比值小于第二阈值时，证明空调器的高低压比有所回落，起到一定的回油效果，此时优先保证室内环境的舒适度，控制空调器保持当前的运行状态继续运行，直至先后两次计算出的高低压比之间的比值大于等于第一阈值时再执行室外机回油操作。其中，“控制空调器保持当前的运行状态继续运行，直至先后两次计算出的高低压比之间的比值大于等于第一阈值时再执行室外机回油操作”的步骤与前述控制过程类似，在此不再赘述。
(3b)如果第一运行频率大于等于第一回油频率但小于第二回油频率，则控制压缩机升频至第二回油频率运行。当第一运行频率大于第一回油频率但小于第二回油频率时，先控制压缩机升频至第二回油频率运行，以期在不改变空调器的运行模式的前提下，使冷冻机油能够顺利回流至压缩机。
进一步地，当压缩机以第二回油频率持续运行第五预设时长时，计算室内换热器的压力与室外换热器的压力之间的第五高低压比；判断第五高低压比与第二高低压比之间的第四比值所处的范围；如果第四比值小于第一阈值且大于等于第二阈值，则执行室外机回油操作；如果第四比值小于第二阈值，则控制空调器保持当前运行状态，直至先后两次计算出的高低压比之间的比值大于等于第一阈值时再执行室外机回油操作。
与前述类似地，第五预设时长可以为5min-20min中的任意值，本申请中取10min，当压缩机以第二回油频率持续运行10min时，理论上已经达到较好的回油效果，此时再次计算室内换热器的压力与室外换热器的压力之间的第五高低压比，并判断第五高低压比与第二高低压之间的第四比值所处的范围，来验证回油效果。如果第四比值仍处于第一阈值与第二阈值之间，证明当前回油效果较差，空调器的高低压比仍在上升，此时控制压缩机直接执行室外机回油操作，以对室外机进行强制回油。当第四比值小于第二阈值时，证明空调器的高低压比有所回落，起到一定的回油效果，此时优先保证室内环境的舒适度，控制空调器保持当前的运行状态继续运行，直至先后两次计算出的高低压比之间的比值大于等于第一阈值时再执行室外机回油操作。其中，“控制空调器保持当前的运行状态继续运行，直至先后两次计算出的高低压比之间的比值大于 等于第一阈值时再执行室外机回油操作”的步骤与前述控制过程类似，在此不再赘述。
(3c)如果第一运行频率大于等于第二回油频率，则控制空调器保持当前运行状态，直至先后两次计算出的高低压比之间的比值大于等于第一阈值时再执行室外机回油操作。如果第一运行频率大于等于第二回油频率，证明当前压缩机处于较高的频率运行，无法再进一步通过升频的方式实现回油，此时控制空调器保持当前运行状态即可，直至先后两次计算出的高低压比之间的比值大于等于第一阈值时再执行室外机回油操作。其中，“控制空调器保持当前的运行状态继续运行，直至先后两次计算出的高低压比之间的比值大于等于第一阈值时再执行室外机回油操作”的步骤与前述控制过程类似，在此不再赘述。
在一种可能的实施方式中，“执行室外机回油操作”的步骤进一步包括：
控制压缩机降频至第一换向频率；控制四通阀换向，以转换成制冷模式；在四通阀换向后，控制室内风机继续运行第六预设时长后关闭；控制压缩机升频至第三回油频率；控制通断阀打开、节流装置关闭至最小开度。
具体地，压缩机的正常工作频率较高，四通阀不能进行换向。因此，在空调器开始执行室外机回油操作时，首先压缩机从正常的工作频率降低至能够允许四通阀进行换向的第一换向频率，以便四通阀能够换向，转换成制冷模式。
在四通阀换向后，空调器运行制冷模式，室内机如果继续送风将向室内吹冷风，给用户带来不好的使用体验。此时，控制室内风机运行第六预设时长，将余热吹出，然后停止运行，避免出风变冷，影响用户体验。其中，第六预设时长可以为10s-1min中的任意值，本申请中可以为30s。
四通阀换向后，控制压缩机升频至第三回油频率，本申请中第三回油频率可以为压缩机的最高频率。在该频率下，压缩机能够以最短的时间提高冷媒的温度和压力，从而提高回油效果。
当运行模式切换为制冷模式后，控制通断阀打开、节流装置关闭至最小开度。控制节流装置关闭到最小开度，即开度为0的状态，节流装置实现完全节流，冷媒无法流过。此时，如图2中箭头所示，压缩机排出的高温高压冷媒流过室外换热器，高温高压冷媒快速冲击室外换热器 的盘管，盘管内部的冷冻机油在高温冷媒的带动下通过回收管路回流到储液器，实现对机油的回收。
一种可能的实施方式中，在“控制通断阀打开，节流装置关闭至最小开度”的步骤之后，控制方法还包括：在通断阀打开并持续第第七预设时长后，控制压缩机降频至第二换向频率；控制四通阀换向，以转换成制热模式；当室内换热器的盘管温度达到防冷风温度时，控制室内风机启动运行；基于设定温度确定第二运行频率，并控制压缩机按照第二运行频率运行；控制通断阀关闭、节流装置打开至预设开度。
其中，第七预设时长可以为5min-15min中的任意值，本申请优选为10min。当通断阀打开、节流装置关闭的时间持续10min时，高温高压冷媒已经循环多次，足以产生较佳的回油效果，因此在通断阀打开、节流装置关闭10min时，可以退出室外机回油操作。
具体地，在室外机回油操作执行完毕后，空调器需要恢复到进入回油操作之前的运行模式，以继续调节室内温度。此时，控制压缩机从当前的工作频率降低至能够允许四通阀进行换向的第二换向频率，以便四通阀能够换向，转换成制热模式。当室内换热器盘管温度达到防冷风温度时，控制室内风机启动运行。当室内换热器的盘管温度达到防冷风温度时，此时启动室内风机运行已经不会向外吹冷风，因此可以控制室内风机启动运行，以满足用户的制热需求。基于设定温度，确定压缩机的第二运行频率，然后控制压缩机以该第二运行频率运行。控制通断阀关闭，节流装置调整至预设开度。优选地，预设开度为节流装置的最大开度。控制节流装置保持最大开度，由于室外机回油操作运行时冷媒在压缩机和室外换热器之间循环，导致室内换热器中冷媒缺失，因此节流装置保持最大开度，使得冷媒迅速充满室内换热器，以尽快实现冷媒的正常循环。
如此，冷媒以正常制热模式的流向流动。至此，回油操作结束。
当然，退出室外机回油操作的方式并非只限于上述一种，在能够使空调器恢复至进入室外机回油操作之前的运行状态的前提下，本领域技术人员可以自由选择具体的控制方式，这种选择并未偏离本申请的原理。例如，可以在室内风机开启的同时室内机的导风板向上送风，防止由于空调刚转换为制热模式时，室内换热器盘管温度过低而出风给用户带来不好的使用体验。
可以看出，通过在制热模式下计算空调器的持续运行时长达到第一预设时长时的第一高低压比，以及达到第二预设时长的第二高低压比，并判断第二高低压比与第一高低压比之间的第一比值所处的范围，然后基于判断结果选择性地执行室外机回油操作，本申请利用空调器运行时的高低压比来判断室外机是否需要回油操作，当需要回油操作时对室外机执行回油操作，使得室外机内积存的冷冻机油及时回到压缩机中，提高室外机的换热效果，提高压缩机运行稳定性。在回油操作时，通过控制空调换热器转换为制冷模式，并打开通断阀、关闭节流装置，能够利用高温高压冷媒的快速流动冲击室外换热器的盘管内部，使得冷冻机油随冷媒一起由回收管路直接返回至储液器内部，实现高效回油。
此外，通过在空调器中设置回收管路，本申请能够在执行室外机回油操作过程中，利用回收管路实现对冷冻机油的回收，实现高温高压冷媒在对室外换热器进行冲刷后，无需再次经过内外换热器，而是直接将冷冻机油带回储液器中进行回收，减少了高温冷媒的流动行程、减少沿程压降，提高室外机回油效果。
需要说明的是，上述控制方式仅为本申请的较为优选的实施例，在不偏离本申请原理的前提下，本领域技术人员可以对上述控制方式进行调整。
例如，在一种可替换的实施方式中，虽然上述实施例是结合第一比值与第一阈值和第二阈值比较进行说明的，但是显然本领域技术人员可以对阈值数量进行调整，这种调整并未偏离本申请的原理。比如，第一比值仅与一个阈值进行比较，或者与三个、四个阈值进行比较等。
再如，在一种可替换的实施方式中，上述实施例中在第一比值小于第一阈值且大于等于第二阈值时的具体操作并非一成不变，本领域技术人员可以在上述控制方法的基础上进行调整，这种调整包括但不限于对回油频率的数量调整、对预设时长的调整、对部分中间过程的步骤删除的调整等。
下面参照图4，对本申请的一种可能的实施过程进行描述。其中，图4为本申请的室外机回油控制方法的一种可能的实施过程的逻辑图。
如图4所示，在一种可能的实施过程中，空调器运行制热模式后，执行下列操作：
首先执行步骤S201，在制热持续运行45min时，分别获取室内换热器的压力P11和室外换热器的压力P21，并计算K1＝P11/P21。
接下来执行步骤S203，在制热持续运行75min时，分别获取室内换热器的压力P12和室外换热器的压力P22，并计算K2＝P12/P22。
接下来执行步骤S205，计算K2/K1并判断K2/K1≥1.5是否成立。当判断结果为成立时，执行步骤S231，否则，当判断结果为不成立时，执行步骤S207。
S207，进一步判断K2/K1＜1.1是否成立。当判断结果为成立时，执行步骤S209；否则，当判断结果为不成立时，执行步骤S211。
S209，控制空调器保持当前运行状态。
S211，获取压缩机的运行频率f并判断运行频率f＜f1是否成立。当判断结果为成立时，执行步骤S213；否则，当判断结果为不成立时，执行步骤S221。
S213，控制压缩机升频至第一回油频率f1并运行10min，然后分别获取室内换热器的压力P13和室外换热器的压力P23，并计算K3＝P13/P23。
然后执行步骤S215，计算K3/K2并判断1.1≤K3/K2＜1.5是否成立。当判断结果为成立时，执行步骤S217，否则，当判断结果为不成立时，执行步骤S227。
S217，控制压缩机升频至第二回油频率f2并运行10min，然后分别获取室内换热器的压力P14和室外换热器的压力P24，并计算K4＝P14/P24。
然后执行步骤S219，计算K4/K3并判断1.1≤K4/K3＜1.5是否成立。当判断结果为成立时，执行步骤S231，否则，当判断结果为不成立时，执行步骤S227。
S221，判断运行频率f＜f2是否成立。当判断结果为成立时，执行步骤S223；否则，当判断结果为不成立时，执行步骤S227。
S223，控制压缩机升频至第二回油频率f2并运行10min，然后分别获取室内换热器的压力P15和室外换热器的压力P25，并计算K5＝P15/P25。
然后执行步骤S225，计算K5/K2并判断1.1≤K5/K2＜1.5是否成立。当判断结果为成立时，执行步骤S231，否则，当判断结果为不成立时，执行步骤S227。
S227，保持当前运行状态，并且每隔10min分别获取室内换热器的压力和室外换热器的压力，并计算二者的高低压力比。
S229，计算相邻的两个高低压力比之间的比值Kn+1/Kn并判断Kn+1/Kn≥1.5是否成立。当判断结果为成立时，执行步骤S231，否则，当判断结果为不成立时，返回继续执行步骤S227。
S231，控制空调器执行室外机回油操作。
本领域技术人员可以理解，上述充空调器还包括一些其他公知结构，例如处理器、控制器、存储器等，其中，存储器包括但不限于随机存储器、闪存、只读存储器、可编程只读存储器、易失性存储器、非易失性存储器、串行存储器、并行存储器或寄存器等，处理器包括但不限于CPLD/FPGA、DSP、ARM处理器、MIPS处理器等。为了不必要地模糊本公开的实施例，这些公知的结构未在附图中示出。
上述实施例中虽然将各个步骤按照上述先后次序的方式进行了描述，但是本领域技术人员可以理解，为了实现本实施例的效果，不同的步骤之间不必按照这样的次序执行，其可以同时(并行)执行或以颠倒的次序执行，这些简单的变化都在本申请的保护范围之内。
至此，已经结合附图所示的优选实施方式描述了本申请的技术方案，但是，本领域技术人员容易理解的是，本申请的保护范围显然不局限于这些具体实施方式。在不偏离本申请的原理的前提下，本领域技术人员可以对相关技术特征作出等同的更改或替换，这些更改或替换之后的技术方案都将落入本申请的保护范围之内。

Claims (10)

  1. 一种室外机回油控制方法，应用于空调器，其特征在于，所述空调器包括通过冷媒管路连接的压缩机、四通阀、室外换热器、节流装置、室内换热器，所述室内换热器上设置有第一压力传感器，所述室外换热器上设置有第二压力传感器，所述空调器还包括回收管路，所述回收管路的一端与所述室外换热器的进口连通，所述回收管路的另一端与所述压缩机的吸气口连通，所述回收管路上设置有通断阀，所述通断阀为常闭阀，
    所述控制方法包括：
    制热模式下，当所述空调器的持续运行时长达到第一预设时长时，计算所述室内换热器的压力与所述室外换热器的压力之间的第一高低压比；
    当所述空调器的持续运行时长达到第二预设时长时，计算所述室内换热器的压力与所述室外换热器的压力之间的第二高低压比；
    判断所述第二高低压比与所述第一高低压比之间的第一比值所处的范围；
    根据判断结果，选择性地执行室外机回油操作；
    其中，所述第二预设时长大于所述第一预设时长。
  2. 根据权利要求1所述的室外机回油控制方法，其特征在于，“根据判断结果，选择性地执行室外机回油操作”的步骤进一步包括：
    如果所述第一比值大于等于第一阈值，则执行所述室外机回油操作。
  3. 根据权利要求2所述的室外机回油控制方法，其特征在于，“根据判断结果，选择性地执行室外机回油操作”的步骤进一步包括：
    如果所述第一比值小于所述第一阈值且大于等于第二阈值，则获取所述压缩机的第一运行频率；
    判断所述第一运行频率与第一回油频率的大小；
    如果所述第一运行频率小于所述第一回油频率，则控制所述压缩机升频至所述第一回油频率运行；
    当所述压缩机以所述第一回油频率持续运行第三预设时长时，计算 所述室内换热器的压力与所述室外换热器的压力之间的第三高低压比；
    判断所述第三高低压比与所述第二高低压比之间的第二比值所处的范围；
    根据判断结果，选择性地执行所述室外机回油操作。
  4. 根据权利要求3所述的室外机回油控制方法，其特征在于，“根据判断结果，选择性地执行所述室外机回油操作”的步骤进一步包括：
    如果所述第二比值小于所述第一阈值且大于等于所述第二阈值，则控制所述压缩机升频至第二回油频率运行；
    当所述压缩机以所述第二回油频率持续运行第四预设时长时，计算所述室内换热器的压力与所述室外换热器的压力之间的第四高低压比；
    判断所述第四高低压比与所述第三高低压比之间的第三比值所处的范围；
    根据判断结果，选择性地执行所述室外机回油操作；并且/或者
    如果所述第二比值小于所述第二阈值，则控制所述空调器保持当前运行状态，直至先后两次计算出的高低压比之间的比值大于所述第一阈值时再执行所述室外机回油操作。
  5. 根据权利要求4所述的室外机回油控制方法，其特征在于，“根据判断结果，选择性地执行所述室外机回油操作”的步骤进一步包括：
    如果所述第三比值小于所述第一阈值且大于等于所述第二阈值，则执行所述室外机回油操作；并且/或者
    如果所述第三比值小于所述第二阈值，则控制所述空调器保持当前运行状态，直至先后两次计算出的高低压比之间的比值大于所述第一阈值时再执行所述室外机回油操作。
  6. 根据权利要求4所述的室外机回油控制方法，其特征在于，所述控制方法还包括：
    如果所述第一运行频率大于等于所述第一回油频率，则进一步判断所述第一运行频率与所述第二回油频率的大小；
    如果所述第一运行频率小于所述第二回油频率，则控制所述压缩机升频至第二回油频率运行；
    当所述压缩机以所述第二回油频率持续运行第五预设时长时，计算所述室内换热器的压力与所述室外换热器的压力之间的第五高低压比；
    判断所述第五高低压比与所述第二高低压比之间的第四比值所处的范围；
    根据判断结果，选择性地执行所述室外机回油操作；并且/或者
    如果所述第一运行频率大于等于所述第二回油频率，则执行所述室外机回油操作。
  7. 根据权利要求6所述的室外机回油控制方法，其特征在于，“根据判断结果，选择性地执行所述室外机回油操作”的步骤进一步包括：
    如果所述第四比值小于所述第一阈值且大于等于所述第二阈值，则执行所述室外机回油操作；并且/或者
    如果所述第四比值小于所述第二阈值，则控制所述空调器保持当前运行状态，直至先后两次计算出的高低压比之间的比值大于所述第一阈值时再执行所述室外机回油操作。
  8. 根据权利要求1所述的室外机回油控制方法，其特征在于，“根据判断结果，选择性地执行室外机回油操作”的步骤进一步包括：
    如果所述第一比值小于第二阈值，则不执行所述室外机回油操作，控制所述空调器保持当前运行状态。
  9. 根据权利要求1所述的室外机回油控制方法，其特征在于，“执行室外机回油操作”的步骤进一步包括：
    控制所述压缩机降频至第一换向频率；
    控制所述四通阀换向，以转换成制冷模式；
    在所述四通阀换向后，控制室内风机继续运行第六预设时长后关闭；
    控制所述压缩机升频至第三回油频率；
    控制所述通断阀打开、所述节流装置关闭至最小开度。
  10. 根据权利要求9所述的室外机回油控制方法，其特征在于，在“控制所述通断阀打开、所述节流装置关闭至最小开度”的步骤之后，所述控制方法还包括：
    在所述通断阀打开并持续第第七预设时长后，控制所述压缩机降频至第二换向频率；
    控制所述四通阀换向，以转换成制热模式；
    当所述室内换热器的盘管温度达到防冷风温度时，控制所述室内风机启动运行；
    基于设定温度确定第二运行频率，并控制所述压缩机按照所述第二运行频率运行；
    控制所述通断阀关闭，所述节流装置打开至预设开度。
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Publication number Priority date Publication date Assignee Title
CN113483476B (zh) * 2021-07-09 2022-07-19 青岛海尔空调器有限总公司 室外机回油控制方法

Citations (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2013257121A (ja) * 2012-06-14 2013-12-26 Mitsubishi Electric Corp 冷凍装置
CN103791658A (zh) * 2014-01-21 2014-05-14 宁波奥克斯电气有限公司 多联式空调机组的油量调控方法
CN106766371A (zh) * 2016-11-29 2017-05-31 珠海格力电器股份有限公司 一种双级压缩机热泵及其回油控制系统和控制方法
CN108489150A (zh) * 2018-02-02 2018-09-04 青岛海尔空调电子有限公司 一种多联机回油控制方法及系统
CN109405353A (zh) * 2018-10-30 2019-03-01 广东美的暖通设备有限公司 回油控制方法及控制系统、存储介质和三管制空调系统
CN110857809A (zh) * 2018-08-24 2020-03-03 青岛海尔空调器有限总公司 空调器及其回油控制方法
CN111426102A (zh) * 2020-04-13 2020-07-17 宁波奥克斯电气股份有限公司 一种提升变频空调回油可靠性的系统、方法及装置
CN113483476A (zh) * 2021-07-09 2021-10-08 青岛海尔空调器有限总公司 室外机回油控制方法

Family Cites Families (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH1163708A (ja) * 1997-08-20 1999-03-05 Fujitsu General Ltd 空気調和機
JP2001091068A (ja) * 1999-09-20 2001-04-06 Fujitsu General Ltd 空気調和機
CN109297151B (zh) * 2018-10-22 2020-12-15 广东美的暖通设备有限公司 空调系统的回油控制方法、装置、存储介质及空调系统
CN112197468A (zh) * 2020-09-28 2021-01-08 珠海格力电器股份有限公司 一种压缩机回油装置、空调系统及回油控制方法
CN112815398B (zh) * 2021-01-18 2022-01-04 珠海格力电器股份有限公司 一种空调及其控制方法

Patent Citations (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2013257121A (ja) * 2012-06-14 2013-12-26 Mitsubishi Electric Corp 冷凍装置
CN103791658A (zh) * 2014-01-21 2014-05-14 宁波奥克斯电气有限公司 多联式空调机组的油量调控方法
CN106766371A (zh) * 2016-11-29 2017-05-31 珠海格力电器股份有限公司 一种双级压缩机热泵及其回油控制系统和控制方法
CN108489150A (zh) * 2018-02-02 2018-09-04 青岛海尔空调电子有限公司 一种多联机回油控制方法及系统
CN110857809A (zh) * 2018-08-24 2020-03-03 青岛海尔空调器有限总公司 空调器及其回油控制方法
CN109405353A (zh) * 2018-10-30 2019-03-01 广东美的暖通设备有限公司 回油控制方法及控制系统、存储介质和三管制空调系统
CN111426102A (zh) * 2020-04-13 2020-07-17 宁波奥克斯电气股份有限公司 一种提升变频空调回油可靠性的系统、方法及装置
CN113483476A (zh) * 2021-07-09 2021-10-08 青岛海尔空调器有限总公司 室外机回油控制方法

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