CN111878892A - Oil return method, device, air conditioner and storage medium for multi-line system - Google Patents

Abstract

An oil return method, device, air conditioner and storage medium for a multi-line system, which relate to the technical field of air conditioners, and include: detecting whether the multi-line system is in an oil return mode, wherein, in the oil return mode, the multi-line system operates in refrigeration mode and return the accumulated lubricating oil to the compressor; if so, obtain the outdoor ambient temperature; determine whether the first temperature preset condition is met according to the outdoor ambient temperature, if so, determine at least one standby indoor unit as the condensing indoor unit, And adjust the switch parts and throttling parts corresponding to the determined condensing indoor unit, so that both the condensing indoor unit and the outdoor unit have a condensing effect. In the invention, in the oil return mode, part of the indoor unit is turned into an outdoor unit, so as to increase the condensation effect, increase the liquid flow rate on the side of the inner unit, and at the same time reduce the system pressure, the compressor frequency can be further improved, the refrigerant flow rate can be increased, and the oil return effect can be improved. , to improve the user's comfort.

Description

Oil return method, device, air conditioner and storage medium for multi-line system

technical field

The present invention relates to the technical field of air conditioners, and in particular, to an oil return method, device, air conditioner and storage medium for a multi-line system.

Background technique

In the multi-line system, after the compressor runs at a low frequency for a period of time, a special refrigeration oil return operation will be performed to return the lubricating oil accumulated in the system to the compressor to ensure that the compressor can operate normally lubricated. The existing refrigeration oil return operation is generally to increase the compressor frequency to increase the refrigerant flow rate; or to increase the valve opening of the indoor unit, so that a certain amount of liquid is returned to the indoor unit side to drive the oil back to the compressor.

The high efficiency of the compressor oil return determines the reliability of the multi-line system. The existing refrigeration oil return operation mainly improves the oil return effect to a certain extent by simply increasing the compressor frequency or increasing the valve opening of the indoor unit. However, due to the corresponding restrictions on the frequency of the compressor and the valve opening of the indoor unit, the improvement of the oil return effect is also limited accordingly, and the efficiency is lacking.

SUMMARY OF THE INVENTION

The invention solves the problem of how to propose a control method for refrigerating oil return which can effectively improve the oil return effect.

In order to solve the above problems, the present invention provides an oil return method for a multi-connection system, wherein the multi-connection system includes one outdoor unit and at least one indoor unit; the control method for the multi-connection refrigeration oil return includes:

Detecting whether the multi-line system is in an oil return mode, wherein, in the oil return mode, the multi-line system operates in a cooling mode and returns the accumulated lubricating oil to the compressor;

If so, get the outdoor ambient temperature;

Judging whether the first preset temperature condition is satisfied according to the outdoor ambient temperature, if satisfied, determining at least one standby indoor unit as the condensing indoor unit, and adjusting the switch components and throttling components corresponding to the determined condensing indoor unit, So that both the condensation indoor unit and the outdoor unit have a condensation function, wherein the standby indoor unit is an indoor unit in a standby state in the multi-line system.

Therefore, when the outdoor ambient temperature reaches a preset condition, the present invention utilizes adjusting a plurality of switch components and throttling components, so that the indoor unit has the same condensing effect as the outdoor unit, that is, the indoor unit is converted through the switch components and the throttling component. It is used as an outdoor unit to increase the condensation effect, increase the refrigerant flow rate, and increase the liquid flow on the side of the indoor unit, which reduces the system pressure, and the compressor frequency can be further increased, effectively improving the oil return effect and improving the user's comfort.

Further, the determining that at least one standby indoor unit is used as a condensing indoor unit includes: judging whether the distance between the standby indoor unit and the outdoor unit is less than a preset length, and if so, determining that the standby indoor unit is the condensing indoor unit. machine.

Therefore, even if the outdoor unit away from the outdoor unit is used as a condensing indoor unit, the oil return efficiency is low. Therefore, the set length condition avoids using the indoor unit away from the outdoor unit to promote oil return, avoiding waste of resources and returning oil. inefficiency.

Further, the first preset temperature condition includes that the outdoor ambient temperature is greater than the first preset temperature.

Therefore, the present invention sets the first temperature preset condition to effectively determine the situation that the outdoor ambient temperature is relatively high. At this time, the operating load of the multi-line system is relatively large, and effective oil return control is required.

Further, the adjusting the determined switch components and throttling components corresponding to the condensing indoor unit so that both the condensing indoor unit and the outdoor unit have a condensing function includes:

Controlling the first electromagnetic valve corresponding to the condensation indoor unit to close, so that the pipeline for refrigerant circulation between the condensation indoor unit and the four-way valve is closed;

and controlling the second solenoid valve corresponding to the condensation indoor unit to open, so that the refrigerant flowing to the inlet of the outdoor unit flows to the inlet of the condensation indoor unit at the same time, wherein the outdoor unit inlet is the refrigerant inlet of the outdoor unit in the cooling mode, The inlet of the condensation indoor unit is the refrigerant outlet of the condensation indoor unit in the cooling mode;

and controlling the electronic expansion valve corresponding to the condensation indoor unit to reach a first preset opening degree, so as to adjust the flow of the refrigerant flowing out of the condensation indoor unit.

As a result, the condensing indoor unit plays a condensing role, the system condensing effect is enhanced, the condensing pressure (high pressure) decreases, the compressor frequency can be further increased, the refrigerant flow rate can be increased, the refrigerant liquid subcooling can be improved, and the liquid refrigerant can drive the oil better. Back to the compressor, it can effectively improve the oil return effect and improve the user's comfort.

Further, it also includes:

Detecting whether the multi-line system exits the oil return mode;

If so, adjust the switch component and the throttle component corresponding to the condensation indoor unit to avoid liquid accumulation in the condensation indoor unit.

Therefore, when the multi-line system exits the oil return mode, the switch components and throttling components corresponding to each condensing indoor unit are adjusted to avoid liquid accumulation in the indoor unit.

Further, adjusting the switch component and the throttling component corresponding to the condensation indoor unit to avoid liquid accumulation in the condensation indoor unit includes:

Control the second solenoid valve corresponding to the condensation indoor unit to close, so as to prevent the refrigerant flowing to the inlet of the outdoor unit from flowing to the inlet of the condensation indoor unit at the same time, wherein the outdoor unit inlet is the refrigerant inlet of the outdoor unit in the cooling mode, so The inlet of the condensation indoor unit is the refrigerant outlet of the condensation indoor unit in the cooling mode; and the electronic expansion valve corresponding to the condensation indoor unit is controlled to reach a second preset opening degree, so as to adjust the refrigerant flowing out from the condensation indoor unit. flow;

Controlling the first solenoid valve corresponding to the condensation indoor unit to open, so as to open the pipeline for refrigerant circulation between the condensation indoor unit and the four-way valve; and controlling the indoor fan corresponding to the condensation indoor unit to operate for a first preset duration ;

When the running duration of the indoor fan reaches the first preset duration, the electronic expansion valve corresponding to the condensing indoor unit is controlled to be closed.

Therefore, when the multi-line system exits the oil return mode, the second solenoid valve is first closed, and the electronic expansion valve is adjusted to the second preset opening degree, so that the auxiliary air pipe is no longer used to transmit the refrigerant; then the first solenoid valve is opened. , the internal fan continues to run for the first preset time to achieve the purpose of normal operation and elimination of liquid accumulation; finally, the internal fan continues to run for the first preset time and then shuts down, and the electronic expansion valve is closed, thus effectively returning to the normal standby state.

Further, it also includes:

Detecting whether the multi-line system exits the oil return mode;

If so, obtain the indoor ambient temperature corresponding to the condensing indoor unit;

It is judged whether the indoor ambient temperature satisfies the second preset temperature condition, and if so, the corresponding condensation indoor unit is controlled to perform temperature adjustment.

Therefore, when the multi-line system exits the oil return mode, since the condensing indoor unit acts as a condenser, the corresponding indoor ambient temperature will inevitably rise. In order to prevent the indoor ambient temperature from being too high, it is necessary to adjust the temperature to effectively avoid excessive temperature. Influence on the indoor environment where the condensing indoor unit is located.

Further, the second preset temperature condition includes: the indoor ambient temperature is always greater than the second preset temperature within the duration.

Thus, the second preset temperature condition is set, and it is effectively determined that the indoor ambient temperature of the condensing indoor unit is relatively high after the oil return is completed.

Further, the temperature adjustment of the condensation indoor unit corresponding to the control includes:

The cooling operation of the corresponding condensing indoor unit is controlled until it is detected that the indoor ambient temperature is lower than a third preset temperature.

Therefore, when the multi-line system exits the oil return mode, the temperature of the condensing indoor unit is adjusted accordingly until the indoor ambient temperature is lower than the third preset temperature, so as to avoid excessive temperature on the indoor furniture where the condensing indoor unit is located. damage.

The second object of the present invention is to provide an oil return device for a multi-line system. By changing part of the indoor unit into an outdoor unit in the oil return mode, the condensation effect is increased, the flow rate of the refrigerant is increased, and the liquid flow on the side of the inner unit is increased. The system pressure is reduced, the compressor frequency is further increased, the oil return effect is improved, and the user's comfort level is improved.

In order to achieve the above object, the technical scheme of the present invention is achieved in this way:

An oil return device of a multi-line system, the multi-line system includes one outdoor unit and at least one indoor unit; the control device for the refrigeration oil return includes:

a detection unit, configured to detect whether the multi-line system is in an oil return mode, wherein, in the oil return mode, the multi-line system operates for cooling and returns the accumulated lubricating oil to the compressor;

Obtaining unit for obtaining the outdoor ambient temperature if yes;

A processing unit, configured to determine whether a first preset temperature condition is satisfied according to the outdoor ambient temperature, and if satisfied, determine at least one standby indoor unit as a condensation indoor unit, and adjust the switch components corresponding to the determined condensation indoor unit and a throttling component, so that both the condensation indoor unit and the outdoor unit have a condensation function, wherein the standby indoor unit is an indoor unit in a standby state in the multi-connection system.

The oil return device of the multi-line system has the same beneficial effects as the above-mentioned oil return method of the multi-line system relative to the prior art, which will not be repeated here.

The third object of the present invention is to provide an air conditioner, by changing part of the indoor units into outdoor units in the oil return mode, increasing the condensation effect, increasing the refrigerant flow rate, increasing the liquid flow rate on the side of the inner unit, and reducing the system pressure, The compressor frequency is further increased, the oil return effect is improved, and the user comfort is improved.

In order to achieve the above object, the technical scheme of the present invention is achieved in this way:

An air conditioner includes a computer-readable storage medium storing a computer program and a processor, and when the computer program is read and run by the processor, the above-mentioned oil return method for a multi-line system is implemented.

The oil return method of the air conditioner and the above-mentioned multi-connection system has the same beneficial effects as compared to the prior art, which will not be repeated here.

The fourth object of the present invention is to provide a computer-readable storage medium, by changing part of the indoor units into outdoor units in the oil return mode, increasing the condensation effect, increasing the flow rate of the refrigerant, increasing the liquid flow on the side of the indoor unit, and promoting the system The pressure is reduced, the compressor frequency is further increased, the oil return effect is improved, and the user's comfort is improved.

In order to achieve the above object, the technical scheme of the present invention is achieved in this way:

A computer-readable storage medium stores a computer program, and when the computer program is read and executed by a processor, the above-mentioned oil return method for a multi-line system is implemented.

The computer-readable storage medium has the same beneficial effects as the above-mentioned oil return method of the multi-line system relative to the prior art, and details are not described herein again.

Description of drawings

FIG. 1 is a schematic structural diagram of a multi-connection system according to an embodiment of the present invention;

FIG. 2 is a schematic flow chart 1 of an oil return method of a multi-line system according to an embodiment of the present invention;

FIG. 3 is a second schematic flowchart of the oil return method of the multi-line system according to the embodiment of the present invention;

FIG. 4 is a schematic flow diagram of adjusting the switch component and the throttling component to avoid liquid accumulation according to an embodiment of the present invention;

FIG. 5 is a schematic flow diagram 3 of the oil return method of the multi-line system according to the embodiment of the present invention;

6 is a schematic structural diagram of an oil return device of a multi-line system according to an embodiment of the present invention;

Reference number:

1-outdoor unit, 2-compressor, 3-four-way valve, 401-first condensing indoor unit, 402-second condensing indoor unit, 403-third condensing indoor unit, 404-running indoor unit, 501-first The first solenoid valve of the condensing indoor unit, 502 - the first solenoid valve of the second condensing indoor unit, 503 - the first solenoid valve of the third condensing indoor unit, 601 - the first auxiliary gas pipe, 602 - the second auxiliary gas pipe, 603 - The third auxiliary gas pipe, 701 - The second solenoid valve of the first condenser indoor unit, 702 - The second solenoid valve of the second condenser indoor unit, 703 - The second solenoid valve of the third condenser indoor unit, 801 - The first electronic Expansion Valve, 802-Second Electronic Expansion Valve, 803-Third Electronic Expansion Valve, 804-Fourth Electronic Expansion Valve, 805-Fifth Electronic Expansion Valve, 901-First Filter, 902-Second Filter, 903 -third filter, 904-fourth filter, 905-fifth filter, 906-sixth filter, 907-seventh filter, 908-eighth filter, 909-ninth filter, 910- Tenth filter, 911- Eleventh filter, 912- Twelfth filter, 1001- First stop valve, 1002- Second stop valve, 1003- Third stop valve, 1004- Fourth stop valve, 11 -Outdoor fan, 12-Oil separator, 13-Steam separator.

Detailed ways

In order to make the above objects, features and advantages of the present invention more clearly understood, the specific embodiments of the present invention will be described in detail below with reference to the accompanying drawings.

At present, the multi-connection system is widely used in many large places and public buildings. A multi-connection system usually includes one outdoor unit and multiple indoor units, and one outdoor unit is connected to multiple indoor units through pipes. In the cooling process, the outdoor side adopts the form of condensation heat exchange, and the indoor side adopts the form of direct evaporative heat exchange, so as to achieve a good cooling effect. In the multi-line system, after the compressor runs at a low frequency for a period of time, a special refrigeration oil return operation will be performed to return the lubricating oil accumulated in the system to the compressor to ensure that the compressor can operate normally lubricated. The existing refrigeration oil return operation is generally to increase the compressor frequency to increase the refrigerant flow rate; or to increase the valve opening of the indoor unit, so that there is a certain amount of liquid return on the indoor unit side to drive the oil back to the compressor.

The high efficiency of the compressor oil return determines the reliability of the multi-line system. The existing refrigeration oil return operation mainly improves the oil return effect to a certain extent by simply increasing the compressor frequency or increasing the valve opening of the indoor unit. However, due to the corresponding restrictions on the frequency of the compressor and the valve opening of the indoor unit, the improvement of the oil return effect is also limited accordingly, and the efficient oil return effect cannot be guaranteed. It can be seen that the development of a control method for refrigeration oil return that can efficiently improve the oil return effect is a technical problem that needs to be solved urgently at present.

FIG. 1 is a schematic structural diagram of a multi-line system for refrigeration oil return according to an embodiment of the present invention, including an outdoor unit 1, at least one indoor unit, a compressor 2 and a four-way valve 3. Specifically, the above-mentioned refrigeration oil return multi-line system The online system also includes an auxiliary air pipe, which is used to connect the first end of the indoor unit and the first end of the outdoor unit 1. The first end of the indoor unit is the refrigerant outlet of the indoor unit in the cooling mode, and the first end of the outdoor unit 1 is the refrigerant outlet. The terminal is the refrigerant inlet of the outdoor unit 1 in cooling mode. Therefore, an auxiliary gas pipe is set up so that the refrigerant flowing to the inlet of the outdoor unit flows to the inlet of the condensing indoor unit at the same time, so that the refrigerant flows from the auxiliary gas pipe directly to the corresponding indoor unit without passing through the condenser of the outdoor unit, further increasing the flow rate of the refrigerant and lifting it back to the indoor unit. Oil effect.

Specifically, referring to Fig. 1, the standby indoor unit is an indoor unit in a standby state in a multi-connection system. In Fig. 1, the indoor unit includes three standby indoor units, and these three standby indoor units are all used as condensers. The state of use, that is, as a condensing indoor unit, so in FIG. 1, the indoor unit includes the first condensing indoor unit 401, the second condensing indoor unit 402, the third condensing indoor unit 403, the running indoor unit 404, and the first condensing indoor unit. 401. The second condensing indoor unit 402 and the third condensing indoor unit 403 are the indoor units in the standby state in the multi-connection system, that is, the condensing indoor unit, which corresponds to the idle room, and the running indoor unit 404 is in the running state in the multi-connection system. The indoor unit corresponds to the room that is using the air conditioner. The first condensing indoor unit 401 corresponds to the first auxiliary air pipe 601, the second condensing indoor unit 402 corresponds to the second auxiliary air pipe 602, and the third condensing indoor unit 403 corresponds to the third auxiliary air pipe 603. Under the action of the corresponding auxiliary air pipe, The heat exchangers of the first condensing indoor unit 401, the second condensing indoor unit 402, and the third condensing indoor unit 403 can play a condensation role, thereby helping to improve the oil return effect. It can be understood that, in the embodiment of the present invention, the condensing indoor unit includes a first condensing indoor unit 401, a second condensing indoor unit 402 . purpose.

Optionally, the indoor unit is configured with a plurality of corresponding switch components and throttling components for adjusting the amount of refrigerant in the plurality of pipes including the auxiliary air pipes, so that the indoor unit has the same condensation effect as the outdoor unit. Therefore, in the present invention, the indoor unit is provided with a plurality of corresponding switch components and a plurality of throttle components, and the indoor unit has the same condensation effect as the outdoor unit by adjusting the plurality of switch components and the plurality of throttle components, that is, The indoor unit is converted into an outdoor unit through the switch component and the throttling component, so as to increase the condensation effect, increase the liquid flow on the side of the indoor unit, and at the same time reduce the system pressure, the compressor frequency can be further increased, the refrigerant flow rate can be increased, and the oil return effect can be improved. Improve user comfort.

Optionally, referring to FIG. 1 , the switch component includes a first solenoid valve and a second solenoid valve, the first solenoid valve is a solenoid valve between the indoor unit and the four-way valve, and the second solenoid valve is a solenoid valve on the auxiliary gas pipe. valve. Therefore, setting the first solenoid valve is to allow the refrigerant from the auxiliary gas pipe to flow through the corresponding indoor unit, effectively preventing the refrigerant from directly flowing back to the compressor; the function of setting the second solenoid valve is to control the refrigerant from the auxiliary gas pipe to pass through the outdoor condenser. , directly to the corresponding internal unit. Through the cooperative use of the first solenoid valve and the second solenoid valve, the indoor unit can effectively perform the condensation function, further increase the flow rate of the refrigerant, and improve the oil return effect.

Specifically, with reference to FIG. 1 , the first solenoid valve 501 of the first condensing indoor unit is used to adjust the refrigerant circulation in the pipeline between the first condensing indoor unit 401 and the four-way valve 3, and the first condensing indoor unit The solenoid valve 502 is used to adjust the refrigerant flow in the pipeline between the second condensation indoor unit 402 and the four-way valve 3 , and the first solenoid valve 503 of the third condensation indoor unit is used to adjust the third condensation indoor unit 403 and the four-way valve 3 Refrigerant circulation between pipes. The second solenoid valve 701 of the first condensing indoor unit is used to adjust the refrigerant circulation of the first auxiliary air pipe 601, the second electromagnetic valve 702 of the second condensing indoor unit is used to adjust the refrigerant circulation of the second auxiliary air pipe 602, and the third condensing indoor unit The second solenoid valve 703 of the machine is used to adjust the refrigerant circulation of the third auxiliary gas pipe 603 .

Optionally, referring to FIG. 1 , the throttling component includes an electronic expansion valve, and the electronic expansion valve is arranged on the pipeline connecting the second end of the corresponding indoor unit and the first branch point, and the first branch point is connected to the outdoor unit at the same time. second end. Therefore, the electronic expansion valve corresponding to the indoor unit is set to effectively prevent throttling and depressurization and reduce the liquid refrigerant in the pipe, so as to avoid affecting the oil return effect.

Specifically, referring to FIG. 1 , the first condensing indoor unit 401 corresponds to the first electronic expansion valve 801, the second condensing indoor unit 402 corresponds to the second electronic expansion valve 802, and the third condensing indoor unit 403 corresponds to the third electronic expansion valve 802. Expansion valve 803. By adjusting the first electronic expansion valve 801, the second electronic expansion valve 802 and the third electronic expansion valve 803, the liquid refrigerant in the refrigerant outlet pipeline corresponding to the condensing indoor unit is prevented from decreasing, and the oil return effect is ensured.

Optionally, with reference to FIG. 1 , the above-mentioned multi-line system for refrigerating oil return further includes: a first filter 901 , a second filter 902 , a third filter 903 , a fourth filter 904 , and a fifth filter 905 , sixth filter 906, seventh filter 907, eighth filter 908, ninth filter 909, tenth filter 910, eleventh filter 911, twelfth filter 912, each filter for Filter the impurities in the corresponding pipeline to prevent clogging the valve.

Optionally, with reference to FIG. 1 , the above-mentioned multi-line system for refrigerating oil return further includes: a first shut-off valve 1001 , a second shut-off valve 1002 , a third shut-off valve 1003 , and a fourth shut-off valve 1004 . It is used to connect pipelines and adjust pipeline pressure.

Optionally, with reference to FIG. 1 , the above-mentioned multi-line system for refrigerating and returning oil further includes: an outdoor fan 11 , an oil separator 12 , and a steam separator 13 , wherein the outdoor fan 11 is used for the fan of the outdoor unit and the oil separator. 12 is used to separate the lubricating oil in the high-pressure steam discharged from the compressor in refrigeration mode to ensure safe and efficient operation, and the steam separator 13 is used to separate the vapor from the liquid to prevent liquid hammer.

The multi-connection system for refrigeration oil return provided by the present invention, by setting auxiliary air pipes, multiple switch components and throttling components, turns some indoor units into outdoor units, increases the condensation effect, increases the liquid flow on the side of the indoor unit, and at the same time the system pressure If it is lowered, the compressor frequency can be further increased, the refrigerant flow rate can be increased, the oil return effect can be improved, and the user comfort can be improved.

FIG. 2 is a schematic flow chart 1 of an oil return method for a multi-line system according to an embodiment of the present invention, including steps S1 to S3, wherein:

In step S1, it is detected whether the multi-line system is in the oil return mode, wherein, in the oil return mode, the multi-line system operates in the cooling mode and returns the accumulated lubricating oil to the compressor. As a result, it can be effectively judged whether the multi-line system is in the oil return mode at first, so as to further control the operation, so as to improve the oil return effect.

In step S2, if yes, the outdoor ambient temperature is acquired. Therefore, according to the outdoor ambient temperature, it can be effectively judged whether it is under severe working conditions, such as high temperature conditions, and the multi-line system needs to further promote the oil return, so as to ensure that the corresponding modulation is carried out at this time to promote the oil return.

In step S3, it is determined whether the first temperature preset condition is satisfied according to the outdoor ambient temperature, and if it is satisfied, at least one standby indoor unit is determined as the condensing indoor unit, and the switch components and throttling components corresponding to the determined condensing indoor unit are adjusted , so that both the condensing indoor unit and the outdoor unit 1 have a condensing effect, wherein the standby indoor unit is the indoor unit in the standby state in the multi-line system. Therefore, the present invention configures the indoor unit with a plurality of corresponding switch components and a plurality of throttling components, and when the outdoor ambient temperature reaches a preset condition, adjusts the plurality of switch components and a plurality of throttling components, so that the indoor unit has The same condensation function as the outdoor unit, that is, the indoor unit is converted into an outdoor unit through the switch parts and throttling parts, so as to increase the condensation effect, increase the liquid flow on the side of the indoor unit, and at the same time reduce the system pressure, and the compressor frequency can be further improved. Increase the refrigerant flow rate, effectively improve the oil return effect, and improve the user's comfort.

Optionally, the above-mentioned determining at least one standby indoor unit as a condensing indoor unit includes: judging whether the distance between the standby indoor unit and the outdoor unit 1 is less than a preset length, and if so, determining that the standby indoor unit is a condensing indoor unit. Referring to Figure 1, it is determined whether the auxiliary air pipe corresponding to the standby indoor unit is smaller than the preset length. Therefore, the length condition is set. Specifically, it is determined whether the length condition is satisfied according to the length of the auxiliary air pipe, so as to avoid the outdoor unit from the outdoor unit being used to promote oil return, thereby avoiding waste of resources and low oil return efficiency.

Optionally, the first preset temperature condition includes that the outdoor ambient temperature is greater than the first preset temperature. Therefore, the present invention sets the first temperature preset condition to effectively determine the situation that the outdoor ambient temperature is relatively high. At this time, the operating load of the multi-line system is relatively large, and effective oil return control is required. In the embodiment of the present invention, the first preset temperature is preferably 43° C., so as to effectively determine the situation in which oil return needs to be promoted.

Optionally, step S3 specifically includes:

The first electromagnetic valve corresponding to the condensing indoor unit is controlled to be closed, so that the pipeline for the refrigerant circulation between the condensing indoor unit and the four-way valve is closed. Thereby, the refrigerant circulation between the condensing indoor unit and the four-way valve is cut off;

And control the second solenoid valve corresponding to the condensing indoor unit to open, so that the refrigerant flowing to the inlet of the outdoor unit flows to the inlet of the condensing indoor unit at the same time. In cooling mode, it is the refrigerant outlet of the condensing indoor unit. This effectively promotes the refrigerant to flow to the outdoor unit inlet and the condensation indoor unit inlet at the same time.

and controlling the electronic expansion valve corresponding to the condensing indoor unit to reach a first preset opening degree, so as to adjust the flow of refrigerant flowing out of the condensing indoor unit. Specifically, referring to FIG. 1 , the first solenoid valve corresponding to the condensing indoor unit is controlled to close, the second solenoid valve corresponding to the condensing indoor unit is controlled to open, and the electronic expansion valve corresponding to the condensing indoor unit is controlled and adjusted to reach the first preset opening. Spend. As a result, the condensing indoor unit plays a condensing role, the system condensing effect is enhanced, the condensing pressure (high pressure) decreases, the compressor frequency can be further increased, the refrigerant flow rate can be increased, the refrigerant liquid subcooling can be improved, and the liquid refrigerant can drive the oil better. Back to the compressor, it can effectively improve the oil return effect and improve the user's comfort. Preferably, the first preset opening degree is the maximum opening degree of the electronic expansion valve, so as to avoid throttling, maximize the refrigerant flow rate, and increase the refrigerant flow rate. It can be understood that, in the embodiment of the present invention, the above-mentioned switch components and throttling components are common hardware, not limited to the first solenoid valve, the second solenoid valve and the electronic expansion valve, as long as the corresponding switching functions and throttling can be realized. function.

FIG. 3 shows a second schematic flowchart of the oil return method of the multi-line system according to the embodiment of the present invention. The above-mentioned control method for the oil return of refrigeration further includes steps S4 to S5, wherein:

In step S4, it is detected whether the multi-line system exits the oil return mode. Therefore, it is first detected whether the multi-line system exits the oil return mode, so as to avoid the continuous use of the standby outdoor unit for condensation, which affects the continuous operation of the multi-line system.

In step S5, if yes, adjust the switch components and throttle components corresponding to the condensing indoor unit to avoid liquid accumulation in the condensing indoor unit. Therefore, when the multi-line system exits the oil return mode, the switch components and throttling components corresponding to the condensing indoor unit are adjusted to avoid liquid accumulation in the indoor unit.

FIG. 4 shows a schematic flowchart of adjusting the switch component and the throttling component to avoid liquid accumulation according to an embodiment of the present invention, including steps S51 to S53.

In step S51, the second solenoid valve corresponding to the condensing indoor unit is controlled to be closed, and the electronic expansion valve corresponding to the condensing indoor unit is controlled to reach a second preset opening degree. Therefore, referring to FIG. 1 , the second solenoid valve is controlled and closed to prevent the refrigerant flowing to the inlet of the outdoor unit from flowing to the inlet of the condensing indoor unit at the same time, wherein the inlet of the outdoor unit is the refrigerant inlet of the outdoor unit 1 in the cooling mode, and the cooling medium In the cooling mode, the indoor unit inlet is the refrigerant outlet of the condensing indoor unit, and the electronic expansion valve is adjusted to the second preset opening degree to adjust the refrigerant flow from the condensing indoor unit. In the embodiment of the present invention, the second preset opening degree is preferably 20 pls, so as to effectively control the refrigerant flow of the corresponding pipeline.

In step S52, the first solenoid valve corresponding to the condensation indoor unit is controlled to open, and the indoor fan corresponding to the condensation indoor unit is controlled to operate for a first preset duration. Therefore, referring to Fig. 1, the first solenoid valve is opened, so that the refrigerant circulation pipeline between the condensing indoor unit and the four-way valve is opened, and the indoor fan continues to run for the first preset period of time to achieve normal operation and eliminate liquid accumulation. the goal of. In the embodiment of the present invention, the first preset time period is preferably 10 minutes, so as to effectively reduce the indoor temperature.

In step S53, when the running duration of the indoor fan reaches the first preset duration, the electronic expansion valve corresponding to the condensing indoor unit is controlled to be closed. Therefore, with reference to FIG. 1 , generally, when the multi-line system exits the oil return mode, the second solenoid valve is first closed, and the electronic expansion valve is adjusted to the second preset opening degree, so that the auxiliary air pipe transmission is no longer used. Refrigerant; then open the first solenoid valve, and the internal fan continues to run for the first preset time to achieve normal operation and eliminate liquid accumulation; finally, the internal fan continues to run for the first preset time and then shuts down, and the electronic expansion valve is closed. Effectively returns to normal standby.

FIG. 5 is a schematic flow chart 3 of an oil return method for a multi-connected system according to an embodiment of the present invention. The above-mentioned control method for oil return from refrigeration further includes steps S6 to S8, wherein:

In step S6, it is detected whether the multi-line system exits the oil return mode. Therefore, it is first detected whether the multi-line system exits the oil return mode, so as to avoid the continuous use of the standby outdoor unit for condensation, which affects the continuous operation of the multi-line system.

In step S7, if yes, obtain the indoor ambient temperature of the condensing indoor unit. In this way, whether the condensing indoor unit needs to be adjusted to the corresponding indoor ambient temperature can be effectively determined based on the indoor ambient temperature.

In step S8, it is determined whether the indoor ambient temperature satisfies the second preset temperature condition, and if so, the corresponding condensing indoor unit is controlled to perform temperature adjustment. Therefore, when the multi-line system exits the oil return mode, since the condensing indoor unit acts as a condenser, the corresponding indoor ambient temperature will inevitably rise. In order to prevent the indoor ambient temperature from being too high, it is necessary to adjust the temperature to effectively avoid excessive temperature. The impact on the indoor environment where the condensing indoor unit is located, such as the high indoor ambient temperature, has an impact on furniture, etc.

Optionally, the second preset temperature condition includes: the indoor ambient temperature is always greater than the second preset temperature within the duration. Thus, the second preset temperature condition is set, and it is effectively determined that the indoor ambient temperature of the condensing indoor unit is relatively high after the oil return is completed. In the embodiment of the present invention, the second preset temperature is preferably 38° C., and the duration is preferably 30 minutes, so as to ensure accurate temperature adjustment.

Optionally, step S8 specifically includes: controlling the cooling operation of the corresponding condensing indoor unit until it is detected that the indoor ambient temperature is lower than the third preset temperature. Therefore, when the multi-line system exits the oil return mode, the temperature of the condensing indoor unit is adjusted accordingly until the indoor ambient temperature is lower than the third preset temperature, so as to avoid excessive temperature on the indoor furniture where the condensing indoor unit is located. damage. In the embodiment of the present invention, the third preset temperature is preferably 32° C. to ensure the effect of final temperature adjustment.

In a specific embodiment of the present invention, the first preset temperature is preferably 43° C., and the first preset opening degree is the maximum opening degree of the electronic expansion valve. Referring to FIG. 1 , when it is detected that the multi-line system enters the oil return In the mode, the acquired outdoor ambient temperature is 45°C (greater than the first preset temperature of 43°C). The outdoor ambient temperature satisfies the first temperature preset condition, and then determines the condensing indoor unit: the first condensing indoor unit 401, the second condensing indoor unit 402, and the third condensing indoor unit 403, and adjusts accordingly, wherein:

For the first condensing indoor unit 401, the first electromagnetic valve 501 of the first condensing indoor unit is closed, the second electromagnetic valve 701 of the first condensing indoor unit is opened, and the first electronic expansion valve 801 is adjusted to the maximum opening degree;

For the second condensing indoor unit 402, the first electromagnetic valve 502 of the second condensing indoor unit is closed, the second electromagnetic valve 702 of the second condensing indoor unit is opened, and the second electronic expansion valve 802 is adjusted to the maximum opening degree;

For the third condensing indoor unit 403, the first electromagnetic valve 503 of the third condensing indoor unit is closed, the second electromagnetic valve 703 of the third condensing indoor unit is opened, and the third electronic expansion valve 803 is adjusted to the maximum opening degree. As a result, the first condensing indoor unit 401, the second condensing indoor unit 402, and the third condensing indoor unit 403 are used as outdoor units, and the oil return operation is accelerated until the oil return is completed.

In a specific embodiment of the present invention, the first preset duration is preferably 10min, and the second preset opening is preferably 20pls. Referring to FIG. 1 , when it is detected that the multi-line system exits the oil return mode, the first preset opening degree is preferably 20pls. The condensing indoor unit 401, the second condensing indoor unit 402, and the third condensing indoor unit 403 are adjusted accordingly, wherein:

For the first condensing indoor unit 401, firstly close the second solenoid valve 701 of the first condensing indoor unit, and adjust the first electronic expansion valve 801 to the second preset opening degree of 20pls; then turn the first electromagnetic valve of the first condensing indoor unit on The valve 501 is opened so that the corresponding indoor fan continues to run for a first preset duration of 60s and then shuts down; finally, when the corresponding indoor fan continues to run for a first preset duration of 60s, the first electronic expansion valve 801 is closed;

For the second condensing indoor unit 402, firstly close the second solenoid valve 701 of the second condensing indoor unit, and adjust the second electronic expansion valve 802 to the second preset opening degree of 20pls; then turn the first electromagnetic valve of the second condensing indoor unit on The valve 502 is opened, so that the corresponding indoor fan continues to run for a first preset duration of 60s and then shuts down; finally, when the corresponding internal fan continues to run for a first preset duration of 60s, the second electronic expansion valve 802 is closed;

For the third condensing indoor unit 403, first close the second solenoid valve 703 of the third condensing indoor unit, and adjust the third electronic expansion valve 803 to the second preset opening degree of 20pls; then turn the first electromagnetic valve of the third condensing indoor unit on The valve 503 is opened so that the corresponding indoor fan continues to run for the first preset duration of 60s and then shuts down; finally, when the corresponding indoor fan continues to run for the first preset duration of 60s, the third electronic expansion valve 803 is closed.

In a specific embodiment of the present invention, the second preset temperature is preferably 38°C, the duration is preferably 30min, and the third preset temperature is preferably 32°C. Referring to FIG. 1 , when it is detected that the multi-connection system exits the In the oil mode, the corresponding indoor temperature adjustment is performed on the first condensing indoor unit 401, the second condensing indoor unit 402, and the third condensing indoor unit 403, and the indoor ambient temperature of the first condensing indoor unit 401 is obtained within a duration of 30 minutes. is 39°C, the indoor ambient temperature of the second condensing indoor unit 402 is 30°C, and the indoor ambient temperature of the third condensing indoor unit 403 is 28°C, so the indoor ambient temperature of the first condensing indoor unit 401 is always 39°C higher than that of the second condensing indoor unit 401. The preset temperature is 38°C, and the indoor ambient temperature of the first condensing indoor unit 401 needs to be adjusted accordingly, wherein: for the second condensing indoor unit 402, the cooling mode is operated at a low wind speed of 26°C until it is detected that the indoor ambient temperature is lower than The third preset temperature is 32°C and the machine is turned off. Generally, the temperature can be effectively reduced by refrigerating for 10 minutes. In this way, damage to the indoor facilities in the idle room corresponding to the first condensing indoor unit 401 due to excessive temperature is effectively avoided.

Another embodiment of the present invention provides an oil return device for a multi-line system. Referring to FIG. 6 , FIG. 6 shows a schematic structural diagram of an oil return device 6000 for a multi-line system according to an embodiment of the present invention, including:

The detection unit 6001 is used to detect whether the multi-line system is in the oil return mode, wherein, in the oil return mode, the multi-line system operates for cooling and returns the accumulated lubricating oil to the compressor;

an obtaining unit 6002, configured to obtain the outdoor ambient temperature if yes;

The processing unit 6003 is used to determine whether the first temperature preset condition is satisfied according to the outdoor ambient temperature, and if satisfied, determine at least one standby indoor unit as the condensation indoor unit, and adjust the switch components and throttle corresponding to the determined condensation indoor unit components, so that both the condensation indoor unit and the outdoor unit 1 have the function of condensation, wherein the standby indoor unit is the indoor unit in the standby state in the multi-line system.

The oil return device of the multi-line system provided by the present invention, by changing some indoor units into outdoor units in the oil return mode, increases the condensation effect, increases the liquid flow on the side of the inner unit, and at the same time reduces the system pressure, and the compressor frequency can be further increased. Lift, increase the refrigerant flow rate, improve the oil return effect, and improve the user's comfort.

Yet another embodiment of the present invention provides an air conditioner, including a computer-readable storage medium storing a computer program and a processor. When the computer program is read and executed by the processor, the above-mentioned oil return method for a multi-line system is implemented. Specifically, referring to FIG. 1 , the air conditioner provided by the embodiment of the present invention is a multi-line system.

In the air conditioner provided by the present invention, in the oil return mode, part of the indoor unit is turned into an outdoor unit to increase the condensation effect, increase the liquid flow rate on the side of the inner unit, and at the same time reduce the system pressure, the compressor frequency can be further improved, and the refrigerant flow rate can be increased. , to improve the oil return effect and improve the user's comfort.

Another embodiment of the present invention provides a computer-readable storage medium, where the computer-readable storage medium stores a computer program, and when the computer program is read and executed by a processor, the above-mentioned oil return method for a multi-line system is implemented.

In the computer-readable storage medium provided by the present invention, in the oil return mode, part of the indoor units are turned into outdoor units, the condensation effect is increased, the liquid flow on the side of the indoor unit is increased, the system pressure is reduced, and the compressor frequency can be further improved, Increase the refrigerant flow rate, improve the oil return effect, and improve the user's comfort.

Although the present invention is disclosed above, the present invention is not limited thereto. Any person skilled in the art can make various changes and modifications without departing from the spirit and scope of the present invention. Therefore, the protection scope of the present invention should be based on the scope defined by the claims.

Claims (12)

1. The oil return method of the multi-split system is characterized in that the multi-split system comprises an outdoor unit (1) and at least one indoor unit; the oil return method of the multi-split air conditioning system comprises the following steps:

detecting whether the multi-split air-conditioning system is in an oil return mode or not, wherein in the oil return mode, the multi-split air-conditioning system operates in a refrigeration mode and enables accumulated lubricating oil to return to the compressor;

if yes, acquiring the outdoor environment temperature;

and judging whether a first temperature preset condition is met or not according to the outdoor environment temperature, if so, determining at least one standby indoor unit as a condensation indoor unit, and adjusting a switch component and a throttling component corresponding to the determined condensation indoor unit to enable the condensation indoor unit and the outdoor unit (1) to have a condensation function, wherein the standby indoor unit is an indoor unit in a standby state in the multi-split system.

2. The oil return method of a multi-split system as claimed in claim 1, wherein the determining at least one standby indoor unit as a condensing indoor unit comprises:

and judging whether the distance between the standby indoor unit and the outdoor unit (1) is less than a preset length, if so, determining that the standby indoor unit is the condensation indoor unit.

3. The oil return method of a multi-split air conditioning system as claimed in claim 1, wherein the first preset temperature condition includes that the outdoor ambient temperature is greater than a first preset temperature.

4. The oil return method of a multi-split system as claimed in claim 1, wherein the adjusting the determined switch unit and throttle unit corresponding to the condensing indoor unit to make the condensing indoor unit and the outdoor unit (1) have a condensing function comprises:

controlling a first electromagnetic valve corresponding to the condensing indoor unit to be closed so as to close a pipeline for refrigerant circulation between the condensing indoor unit and the four-way valve;

controlling a second electromagnetic valve corresponding to the condensing indoor unit to be opened so that the refrigerant flowing to an inlet of the outdoor unit simultaneously flows to an inlet of the condensing indoor unit, wherein the inlet of the outdoor unit is a refrigerant inlet of the outdoor unit (1) in a refrigerating mode, and the inlet of the condensing indoor unit is a refrigerant outlet of the condensing indoor unit in the refrigerating mode;

and controlling an electronic expansion valve corresponding to the condensation indoor unit to reach a first preset opening degree so as to adjust the flow of the refrigerant flowing out of the condensation indoor unit.

5. The oil return method of a multi-split system as set forth in claim 1, further comprising:

detecting whether the multi-split air conditioning system exits the oil return mode or not;

if so, adjusting the switch component and the throttling component corresponding to the condensation indoor unit to avoid liquid accumulation in the condensation indoor unit.

6. The oil return method of a multi-split system as claimed in claim 5, wherein the adjusting the switch component and the throttling component corresponding to the condensing indoor unit to avoid liquid loading in the condensing indoor unit comprises:

controlling a second electromagnetic valve corresponding to the condensing indoor unit to be closed so as to prevent a refrigerant flowing to an inlet of the outdoor unit from simultaneously flowing to an inlet of the condensing indoor unit, wherein the inlet of the outdoor unit is a refrigerant inlet of the outdoor unit (1) in a refrigeration mode, and the inlet of the condensing indoor unit is a refrigerant outlet of the condensing indoor unit in the refrigeration mode; controlling an electronic expansion valve corresponding to the condensing indoor unit to reach a second preset opening degree so as to adjust the flow of a refrigerant flowing out of the condensing indoor unit;

controlling a first electromagnetic valve corresponding to the condensing indoor unit to be opened so as to open a pipeline for refrigerant circulation between the condensing indoor unit and the four-way valve; controlling an inner fan corresponding to the condensation indoor unit to operate for a first preset time;

and when the running time of the inner fan reaches the first preset time, controlling the electronic expansion valve corresponding to the condensation indoor unit to be closed.

7. The oil return method of a multi-split system as set forth in claim 1, further comprising:

detecting whether the multi-split air conditioning system exits the oil return mode or not;

if so, acquiring the indoor environment temperature corresponding to the condensation indoor unit;

and judging whether the indoor environment temperature meets a second temperature preset condition, and if so, controlling the corresponding condensation indoor unit to carry out temperature regulation.

8. The oil return method of a multi-split system as claimed in claim 7, wherein the second preset temperature condition includes: the indoor ambient temperature is always greater than a second preset temperature for the duration.

9. The oil return method of a multi-split system as claimed in claim 7, wherein the controlling the corresponding condensing indoor unit to perform temperature adjustment includes:

and controlling the indoor unit of the condensation chamber meeting the second temperature preset condition to perform cooling operation until the indoor environment temperature is detected to be lower than a third preset temperature.

10. The oil return device of the multi-split system is characterized in that the multi-split system comprises an outdoor unit (1) and at least one indoor unit; the control device for refrigeration oil return comprises:

the detection unit is used for detecting whether the multi-split air conditioning system is in an oil return mode, wherein in the oil return mode, the multi-split air conditioning system operates to refrigerate and make accumulated lubricating oil return to the compressor;

the acquisition unit is used for acquiring the outdoor environment temperature if the outdoor environment temperature is lower than the preset outdoor environment temperature;

and the processing unit is used for judging whether a first temperature preset condition is met or not according to the outdoor environment temperature, if so, determining at least one standby indoor unit as a condensation indoor unit, and adjusting a switch component and a throttling component corresponding to the determined condensation indoor unit so that the condensation indoor unit and the outdoor unit (1) have condensation functions, wherein the standby indoor unit is an indoor unit in a standby state in the multi-split system.

11. An air conditioner comprising a computer-readable storage medium storing a computer program and a processor, the computer program being read by the processor and executing the oil return method of the multi-split air conditioner according to any one of claims 1 to 9.

12. A computer-readable storage medium, characterized in that the computer-readable storage medium stores a computer program, which is read and executed by a processor, and implements the oil return method of a multi-split air-conditioning system according to any one of claims 1 to 9.

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