CN113251732A

CN113251732A - Refrigeration system and control method

Info

Publication number: CN113251732A
Application number: CN202110476359.6A
Authority: CN
Inventors: 张吕超; 田永林; 张福华
Original assignee: TCL Air Conditioner Zhongshan Co Ltd
Current assignee: TCL Air Conditioner Zhongshan Co Ltd
Priority date: 2021-04-29
Filing date: 2021-04-29
Publication date: 2021-08-13

Abstract

The application discloses refrigerating system and control method, refrigerating system is including the compressor, cross valve, first heat exchanger, throttle part and the second heat exchanger that connect gradually, refrigerating system still includes: the electronic expansion valve is respectively connected with the air return pipe of the compressor and the throttling component and is used for adjusting the opening degree of the electronic expansion valve according to different modes of the refrigeration system; and the heat supply device is respectively connected with the throttling component and the second heat exchanger and is used for storing the refrigerant and/or heating the refrigerant. The refrigeration system and the control method provided by the embodiment of the application can not only avoid the discomfort caused by overlarge temperature variation of a user, but also cool the refrigerant in a mode of controlling the opening degree of the electronic expansion valve, thereby preventing the problem of compressor frequency reduction caused by overhigh temperature of the refrigerant.

Description

Refrigeration system and control method

Technical Field

The application relates to the field of refrigeration systems, in particular to a refrigeration system and a control method.

Background

The refrigeration system sold in the market at present mostly adopts the cooling and heating machines, and the heating cycle of the cooling and heating machines is realized by changing an indoor heat exchanger into a condenser and changing the indoor heat exchanger into an evaporator through the reversing of an electromagnetic four-way valve to carry out heat pump cycle, so that the purpose of conveying the heat of an outdoor low-temperature area to an indoor high-temperature area is achieved. When the outdoor temperature is lower than a certain temperature and the outdoor air humidity is higher, frost is separated out from the outdoor heat exchanger due to the fact that the evaporation temperature is lower than the frost point temperature, the frost can lower the heat exchange efficiency of the outdoor heat exchanger, and the heating effect of the indoor heat exchanger is further poor.

Refrigerating system is equipped with the defrost mode among the prior art usually, but when refrigerating system opened the defrost mode, indoor meeting stopped heating for indoor temperature reduces fast, and user's comfort reduces. Meanwhile, in north america, northern europe and other areas, the problem that frost cannot be removed completely in the defrosting mode is often caused due to the fact that the outdoor temperature is too low. In the defrosting mode, hot gas defrosting is carried out by replacing a heat pump cycle with a refrigerating cycle, so that the indoor heat exchanger can not be heated and can be frosted sometimes, although the existing refrigerating system can carry out indoor cold air prevention setting, the indoor heat exchanger still needs to be preheated for a long time after the existing refrigerating system exits from the defrosting mode, the duration of the whole defrosting process is prolonged, meanwhile, the indoor temperature change range is large, and the comfort of a user is greatly reduced.

Accordingly, there is a need in the art for a refrigeration system that overcomes the above-mentioned deficiencies.

Disclosure of Invention

An object of the present application is to provide a refrigeration system and a control method thereof, so as to solve the problem that the indoor temperature variation range is large when an outdoor heat exchanger of the refrigeration system is in a low temperature environment.

In order to achieve the above object, an embodiment of the present application provides a refrigeration system, including a compressor, a four-way valve, a first heat exchanger, a throttling component and a second heat exchanger that are connected in sequence, the refrigeration system further includes: the electronic expansion valve is respectively connected with the air return pipe of the compressor and the throttling component and is used for adjusting the opening degree of the electronic expansion valve according to different modes of the refrigeration system; and the heat supply device is respectively connected with the throttling component and the second heat exchanger and is used for storing the refrigerant and/or heating the refrigerant.

Further, when the first mode of the refrigeration system is switched, the heating device starts heating, and the electronic expansion valve adjusts the opening degree of the electronic expansion valve in real time according to the temperature of the refrigerant so as to reduce the temperature of the refrigerant entering the compressor.

Further, when the mode is switched to the second mode of the refrigeration system, the electronic expansion valve is closed, and the heat supply device is used for storing part of the refrigerant.

Further, the refrigeration system further includes: the first switch valve is respectively connected with the throttling component and the second heat exchanger and is used for being opened or closed according to different modes of the refrigeration system; the second switch valve is respectively connected with the heating device and the second heat exchanger and is used for being opened or closed according to different modes of the refrigeration system; the second switch valve and the heat supply device are arranged in series and are arranged in parallel with the first switch valve.

Further, when the first mode of the refrigeration system is switched, the first switch valve is closed, the second switch valve is opened, the heating device starts heating, and the electronic expansion valve adjusts the opening degree of the electronic expansion valve in real time according to the temperature of the refrigerant so as to reduce the temperature of the refrigerant entering the compressor.

The embodiment of the application also provides a control method for the refrigeration system, and the control method comprises the following steps: starting the heating function of the heating device; judging whether the real-time numerical value of the refrigerant in the muffler of the compressor is within a preset range or not; the real-time value is a temperature value and/or a dryness value of the refrigerant. And if the real-time numerical value of the refrigerant in the muffler of the compressor is judged not to be in the preset range, adjusting the self opening of the electronic expansion valve in real time.

Further, in the step of determining whether the real-time value of the refrigerant in the muffler of the compressor is within a preset range, if it is determined that the real-time value of the refrigerant in the muffler of the compressor is within the preset range, the adjustment of the opening degree of the electronic expansion valve is stopped.

Further, before the step of starting the heating function of the heating apparatus, the method includes: determining a current operating mode of the refrigeration system; if the current working mode is determined to be the first mode, executing the step of starting the heating function of the heating device; the first mode is a mode in which the refrigeration system needs to heat when the outdoor environment temperature is within a first preset temperature range.

Further, after the step of determining the current operation mode of the refrigeration system, the control method further includes: if the current working mode is determined to be the second mode, closing the electronic expansion valve, closing the first switch valve and opening the second switch valve; the second mode is a mode in which the refrigeration system needs to refrigerate when the outdoor environment temperature is within a second preset temperature range.

Further, after the step of determining the current operation mode of the refrigeration system, the control method further includes: if the current working mode is determined to be the third mode, closing the electronic expansion valve, closing the first switch valve, opening the second switch valve and starting the heating function of the heating device; the third mode is a mode in which the refrigeration system needs to refrigerate when the outdoor environment temperature is within a third preset temperature range.

According to the refrigeration system and the control method, the mode of adding the heat supply device is adopted, the sudden drop of the indoor temperature when the refrigeration system is in the defrosting mode is avoided, the discomfort caused by the overlarge temperature variation of a user is avoided, meanwhile, the heat supply device can also preheat the refrigerant when the ambient temperature is too low, the outdoor fan does not need to enter the anti-freezing protection mode due to the fact that frosting is too much, further, the outdoor fan is prevented from being frequently started and stopped, and the service life of the outdoor fan is prolonged. The refrigerant can be cooled by controlling the opening degree of the electronic expansion valve, so that the problem that the compressor is lowered in frequency due to overhigh temperature of the refrigerant is solved.

Drawings

The technical solution and other advantages of the present application will become apparent from the detailed description of the embodiments of the present application with reference to the accompanying drawings.

Fig. 1 is a schematic structural diagram of a refrigeration system provided in embodiment 1 of the present application.

Fig. 2 is a partial structural schematic view of the heating apparatus provided in fig. 1.

Fig. 3 is an exploded view of the heating apparatus provided in fig. 1.

Fig. 4 is a schematic partial structure diagram of an outdoor unit according to embodiment 1 of the present application.

Fig. 5 is a flowchart of a control method provided in embodiment 1 of the present application.

Fig. 6 is a schematic structural diagram of a refrigeration system provided in embodiment 2 of the present application.

Description of reference numerals:

reference part name

100 refrigeration system 110 compressor

120 four-way valve 130 first heat exchanger

140 throttling member 150 second heat exchanger

160 electronic expansion valve 170 heating device

180 first switching valve 190 second switching valve

171 top cover 172 bottom cover

173 electric heating pipe 174T head pipe

175 spout tube 176 cylinder

210 fan motor 220 frequency conversion electric controller

230 middle partition 240 chassis

Detailed Description

The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application. It is to be understood that the embodiments described are only a few embodiments of the present application and not all embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present application.

Example 1

Referring to fig. 1, different line patterns represent the flow direction of the refrigerant in different modes. The present embodiment provides a refrigeration system 100 including a compressor 110, a four-way valve 120, a first heat exchanger 130, a throttling part 140, a second heat exchanger 150, an electronic expansion valve 160 connected to a return pipe of the compressor 110 and the throttling part 140, respectively, and a heating apparatus 170 connected to the throttling part 140 and the second heat exchanger 150, respectively, which are connected in this order. In this embodiment, the first heat exchanger 130 is an indoor heat exchanger, and the second heat exchanger 150 is an outdoor heat exchanger. In this embodiment, the throttling component 140 may be a capillary module, that is, the main capillary, the auxiliary capillary, and the one-way valve connected in sequence achieve the throttling and pressure reducing effects. The throttling element may alternatively be an electronic expansion valve. Since the throttling and pressure reducing effect of the capillary tube is determined according to the design parameters (such as the diameter parameter or the length parameter), the capillary tube cannot execute the excessively complicated throttling and pressure reducing control command. Therefore, the throttling component of the embodiment can intelligently adjust various parameters of the throttling component in a mode of using the electronic expansion valve, so that the control of the refrigeration system is more intelligent.

The electronic expansion valve 160 is used to adjust its opening according to different modes of the refrigeration system 100. The heating device is used for storing the refrigerant and/or heating the refrigerant.

When switching to the first mode of the refrigeration system, the heating apparatus 170 starts heating, and the electronic expansion valve 160 adjusts its opening degree in real time according to the refrigerant temperature to lower the temperature of the refrigerant entering the compressor 110. In this embodiment, the first mode is specifically a low-temperature heating mode or an ultra-low-temperature heating mode (i.e., when the ambient temperature of the outdoor heat exchanger is within a first preset temperature range, the indoor heat exchanger in the refrigeration system needs to heat, where the first preset temperature range may be selected from 0 ℃ to-15 ℃ or from-15 ℃ to-25 ℃, but is not limited thereto, and a manufacturer may set the first preset temperature range according to actual requirements).

When switching to the second mode of the refrigeration system, the electronic expansion valve 160 is closed, and the heating device 170 does not heat in the second mode to store a part of the refrigerant. In this embodiment, the second mode is specifically a low-temperature cooling mode (i.e., a mode in which the indoor heat exchanger in the cooling system needs to cool when the ambient temperature of the outdoor heat exchanger is within a second predetermined temperature range, where the second predetermined range may be 0 ℃ to-15 ℃, but is not limited thereto, and a manufacturer may set the second predetermined temperature range according to actual requirements).

When switching to the third mode of the refrigeration system, the electronic expansion valve 160 is closed, and the heating device 170 preheats the refrigerant flowing into the indoor heat exchanger to prevent the indoor heat exchanger from frosting. Because the problem of frosting of the indoor heat exchanger is solved, the outdoor fan does not need to be started and stopped intermittently, and the compressor does not enter an anti-freezing protection mode, so that the service life of the compressor can be prolonged. Meanwhile, the outdoor fan does not need to be intermittently started and stopped, and the indoor temperature value cannot be intermittently changed, so that the comfort of a user is improved. In this embodiment, the third mode is specifically an ultra-low temperature refrigeration mode (i.e. a mode in which the indoor heat exchanger still needs to refrigerate when the ambient temperature of the outdoor heat exchanger is within a third preset temperature range, where the third preset range may be, but is not limited to, 15 ℃ below zero to 25 ℃ below zero, and a manufacturer may set the third preset temperature range according to actual requirements).

The refrigeration system 100 includes the above three modes, but is not limited to the above three modes, that is, the refrigeration system 100 further includes at least a conventional refrigeration mode or a conventional heating mode, and so on, which are not described herein again.

In other embodiments, the refrigeration system 100 further includes a control module for automated coordinated control of various components of the refrigeration system.

For example, referring to fig. 2 and 3, in the present embodiment, a schematic structural diagram of the heating apparatus 170 is provided, but the present invention is not limited to this structure, and the heating apparatus 170 may be any liquid storage tank with a heating function. The heating apparatus 170 of the present embodiment includes a top cover 171, a cylinder 176, and a bottom cover 172 connected in sequence. The top cover 171 and the bottom cover 172 are respectively provided with two through holes, and each through hole of the top cover 171 and each through hole of the bottom cover 172 are correspondingly arranged. The heating apparatus 170 further includes an electric heating pipe 173, a T-head pipe 174, and a nozzle pipe 175. The two through holes of the top cover 171 are used for fixing two ends of the electric heating tube 173, and the electric heating tube 173 is a U-shaped heating tube. One end of the T-head pipe 174 and one end of the spout pipe 175 pass through the two through holes of the bottom cover, respectively. An electric heating pipe 173, a T-head pipe 174, and a spout pipe 175 are accommodated in the cylinder. The cylinder 176 is connected to the top cap 171 at one end and to the bottom cap 172 at the other end to protect the electric heating pipe 173, the T-head pipe 174 and the spout pipe 175. The nozzle pipe 175 is provided with a plurality of injection holes and a plurality of oil return holes, and the T-head pipe 174 is also provided with a plurality of oil return holes.

In the present embodiment, the refrigeration system 100 further includes a first on-off valve 180 and a second on-off valve 190. Specifically, the first switching valve 180 is connected to the throttling part 140 and the second heat exchanger 150, respectively, to be turned on or off according to different modes of the refrigeration system 100. The second switching valve 190 is connected to the heating device 170 and the second heat exchanger 150, respectively, to be turned on or off according to different modes of the refrigeration system. The second switching valve 190 is connected in series with the heating apparatus 170 and in parallel with the first switching valve 180. Specifically, the first and second switching valves 180 and 190 may be selected as two-way solenoid valves.

When the refrigeration system 100 is in the ordinary heating mode and the outdoor temperature is low, if the control module determines that the outdoor heat exchanger is frosted, the low-temperature heating mode is started, the first switch valve 180 is closed, the second switch valve 190 is opened, and the heating function of the heating device is started. Alternatively, the user may directly adjust the mode of the refrigeration system through the control module, and the embodiment does not limit the manner of triggering the mode switching. The low-temperature low-pressure refrigerant (mainly in liquid state and containing a small amount of flash steam) flowing through the throttling component enters the heat supply device through the inlet of the nozzle pipe of the heat supply device, and the heat supply device heats and vaporizes the refrigerant and heats the refrigerant to above 0 ℃. The refrigerant enters the outdoor heat exchanger from the T-head pipe through the second on-off valve 190 to melt frost on the outdoor heat exchanger, and then enters the compressor return pipe.

In the present embodiment, considering the heating effect of the heating device 170, the refrigerant will be changed into a gas with a large superheat degree when reaching the return pipe of the compressor 110, and the density of the refrigerant is relatively small at this time, and if the refrigerant is directly sucked into the compressor without any treatment, the circulation amount of the refrigerant in the refrigeration system 100 will be relatively small, and further the indoor heating amount will be reduced; in addition, since the discharge temperature of the compressor 110 is excessively high and the compressor 110 is lowered in frequency if the degree of superheat of the gas is excessively high, and finally the heating capacity is decreased, in order to avoid this, an electronic expansion valve 160 is provided between the throttle member 140 and the compressor 110. When the temperature of the refrigerant in the air return pipe is too high, the electronic expansion valve 160 is opened, and the opening degree of the electronic expansion valve 160 is adjusted to control a certain flow of low-temperature liquid refrigerant to directly flow into the air return pipe, and the low-temperature liquid refrigerant cools the refrigerant in the air return pipe, and when the dryness or temperature of the mixed refrigerant is within a preset range, the mixed refrigerant is sucked into the compressor 110 for continuous circulation. Preferably, the upper and lower limits of the predetermined range are about 0.9 dryness. And when the frost of the outdoor heat exchanger is completely melted, the control module exits the low-temperature heating mode and restores the common heating mode. In this embodiment, the control module can directly perform automatic control on the mode. Optionally, the user may also instruct the refrigeration system to switch the mode through a control terminal.

When the refrigeration system 100 is in the low-temperature heating mode, and the control module detects that the operating frequency is at the highest frequency, and the indoor temperature still does not reach the set value (that is, the outdoor heat exchanger does not frost, but the indoor temperature does not reach the standard), the refrigeration system 100 may enter the ultra-low-temperature heating mode. Alternatively, the user may also manually switch the modes. In the ultra-low-temperature heating mode, the refrigeration system may perform heating through the electric heating pipe 173 of the heating apparatus 170. Since the outdoor heat exchanger is not frosted in this mode, the temperature value of the refrigerant generated through the heating device 170 is not necessarily higher than 0 ℃.

When the refrigeration system 100 is in a normal refrigeration mode and the outside temperature is slightly low, the demand of the refrigerant circulation amount in the refrigeration cycle is reduced, and at this time, if too much refrigerant participates in the circulation, most of liquid refrigerant accumulates in the heat exchange tube of the outdoor heat exchanger, so that the effective heat exchange area of the outdoor heat exchanger is reduced, and the refrigeration energy efficiency ratio is further influenced. At this time, the control module can send out a mode conversion instruction according to various parameters such as the outer ring temperature, the press frequency, the inner ring temperature, the inner pipe temperature and the like, and the mode of the refrigeration system 100 is adjusted from the ordinary refrigeration mode to the low-temperature refrigeration mode. Alternatively, the user may directly adjust the mode of the refrigeration system through the control module, and the present embodiment does not limit the mode switching manner of the refrigeration system 100. In the low temperature cooling mode, the refrigeration system 100 closes the first switching valve 180 and opens the second switching valve 190. After the refrigerant is condensed into a liquid refrigerant of normal temperature and high pressure by the outdoor heat exchanger, the refrigerant enters the heating apparatus 170 through the T-head pipe 174. In this case, the heating apparatus 170 is not heated, and serves only as a liquid reservoir for the refrigerant. The liquid refrigerant is delivered to the throttling element 140 through the nozzle pipe 175, and then delivered to the indoor heat exchanger for evaporation and refrigeration. Since part of the refrigerant is stored in the heating apparatus 170, the total amount of the refrigerant participating in the circulation system is reduced, and the refrigerant can be prevented from accumulating in the heat exchange tube of the outdoor heat exchanger, thereby improving the heat exchange efficiency of the refrigeration system. If the outdoor temperature rises or the indoor temperature decreases, the control module switches the low-temperature refrigeration mode to the ordinary refrigeration mode. Optionally, the user may also manually switch the low-temperature cooling mode to the normal cooling mode.

Since some users still have refrigeration requirements when the outdoor temperature is in the temperature range from-15 ℃ to-25 ℃ (for example, places such as basements, cellars, dance halls, etc. where the indoor temperature is high and the outdoor temperature is low but the ventilation is poor), the refrigeration system 100 should also have an operation mode of ultra-low temperature refrigeration. In the prior art, a refrigerant is compressed by a compressor, and high-temperature and high-pressure gas is discharged from an exhaust port and enters an outdoor heat exchanger to be condensed into a liquid state. Because the outdoor environment is too low, the temperature of the condensed high-pressure liquid is very low, and if the condensed high-pressure liquid directly enters the indoor heat exchanger through the throttling component, the indoor heat exchanger can be frosted rapidly, and the refrigerating effect of the refrigerating system is influenced. If the frost is excessive, the compressor enters an anti-freezing protection mode, and refrigeration is stopped. Therefore, in the prior art, the condensation temperature is indirectly controlled by intermittently starting and stopping the outdoor fan. However, since there is a lower limit to the fan speed (which generally cannot be lower than 300RPM), intermittent start and stop can cause a significant impact on the refrigeration system. Moreover, the problem of frosting of the indoor heat exchanger cannot be fundamentally solved by intermittent start and stop, the compressor still enters an anti-freezing protection mode, refrigeration is stopped, and user experience is very poor.

In view of the above technical problem, the refrigeration system 100 provided in the present embodiment is provided with an ultra-low temperature refrigeration mode. When the outdoor temperature is below a certain temperature (e.g., 15 ℃ below zero), and refrigeration is still occurring, the refrigeration system 100 enters the ultra-low temperature refrigeration mode. Alternatively, the user may manually enter the ultra-low temperature cooling mode. In the ultra-low-temperature refrigeration mode, the refrigeration system 100 closes the first switching valve 180, opens the second switching valve 190, and closes the electronic expansion valve 160. The liquid refrigerant condensed by the outdoor heat exchanger enters the heating apparatus 170 through the T-head pipe 174 of the heating apparatus, and the heating apparatus 170 turns on the heating function of the electric heating pipe 173. When the refrigerant is heated to a predetermined temperature (preferably about 40 ℃), the refrigerant is input to the throttling member 140 through the nozzle pipe 175, and is subjected to evaporation heat exchange by the indoor heat exchanger. In the ultra-low temperature refrigeration mode, the heating device 170 can preheat the refrigerant before throttling, and the problem of frosting of the indoor heat exchanger is thoroughly solved.

Through the design, the indoor heat exchanger cannot frost, the outdoor fan cannot be intermittently started or stopped, and the compressor cannot enter an anti-freezing protection mode. Therefore, the indoor temperature does not change intermittently with the external fan, and the indoor temperature is maintained in a comfortable range so as to improve the comfort of users. When the outdoor temperature is higher than a certain temperature (such as 16 ℃ below zero), the control module switches the ultra-low temperature refrigeration mode to the ordinary refrigeration or low temperature refrigeration mode. Alternatively, the user may also manually switch the mode to either mode.

Referring to fig. 4, in particular, some of the components provided in this embodiment may be installed in an outdoor unit of a refrigeration system. For example: one or more components of the compressor 110, the four-way valve 120, the throttling part 140, the second heat exchanger 150, the electronic expansion valve 160, the heating device 170, the first switching valve 180, and the second switching valve 190 are installed into the outdoor unit. In addition, the outdoor unit may further include, but is not limited to, the following components: 210 fan motors, 220 variable-frequency electric controllers, 230 middle partition plates and 240 chassis. Although not shown in the drawings, it is understood that the outdoor unit may further include: axial fan, top cover plate, axial fan blade and other conventional outdoor unit parts such as air-out grid, these some outdoor unit parts are refrigerating system's conventional part, and this is not repeated herein.

The cooling system 100 that this embodiment provided has avoided the cooling system to be in the sudden drop of indoor temperature when defrosting the mode through the mode that adds heating device, has avoided the uncomfortable sense that the user produced because of temperature variation is too big, and this heating device can also preheat the refrigerant when ambient temperature crosses lowly simultaneously for outdoor fan need not be because of frosting too much gets into the protection mode that prevents frostbite, and then has avoided outdoor fan to frequently open and stop, has increased outdoor fan's life. The refrigerant can be cooled by controlling the opening degree of the electronic expansion valve 160, so that the problem of compressor frequency reduction caused by overhigh temperature of the refrigerant is solved.

Referring to fig. 5, based on the refrigeration system, the present embodiment further provides a control method, where the control method includes the following steps:

and step S100, starting a heating function of the heating device.

Step S200, judging whether the real-time numerical value of the refrigerant in the muffler of the compressor is in a preset range. The real-time value is a temperature value and/or a dryness value of the refrigerant. Illustratively, when the preset range is a temperature value, the preset range is 0 ℃ to-15 ℃ or-15 ℃ to-25 ℃ to enter the low-temperature heating mode or the ultra-low-temperature heating mode of the refrigeration system. But not limited thereto, the manufacturer may set the predetermined temperature range according to actual requirements. This step can prevent the refrigerant that is not processed from being directly sucked into the compressor, which results in a small amount of refrigerant circulation in the refrigeration system 100, and thus causes a decrease in the amount of indoor heating; in addition, if the degree of superheat of the gas is too large, the exhaust temperature of the compressor is too high, the compressor is further lowered in frequency, and finally the heating capacity is reduced.

And step S300, if the real-time numerical value of the refrigerant in the muffler of the compressor is judged not to be in the preset range, adjusting the self opening of the electronic expansion valve in real time. And if the real-time numerical value of the refrigerant in the muffler of the compressor is judged to be in the preset range, stopping adjusting the opening degree of the electronic expansion valve. When the temperature of the refrigerant in the air return pipe is too high, the opening degree of the electronic expansion valve is adjusted to control a certain flow of low-temperature liquid refrigerant to directly flow into the air return pipe, the low-temperature liquid refrigerant can cool the refrigerant in the air return pipe, when the dryness or the temperature of the mixed refrigerant is within a preset range, the adjustment of the opening degree of the electronic expansion valve is stopped, and the mixed refrigerant is sucked into the compressor 110 for continuous circulation, so that the problem of heating quantity reduction caused by the frequency reduction of the compressor is solved.

In other embodiments, the following steps are further included before step S100: a current operating mode of the refrigeration system is determined. If the current working mode is determined to be the first mode, executing step S100; the first mode is a mode in which the refrigeration system needs to heat when the outdoor environment temperature is within a first preset temperature range. The first predetermined temperature range may be selected from 0 ℃ to-15 ℃ or-15 ℃ to-25 ℃, but is not limited thereto, and the manufacturer may set the first predetermined temperature range according to actual requirements.

After the step of determining the current operation mode of the refrigeration system, the control method further includes: if the current working mode is determined to be the second mode, closing the electronic expansion valve, closing the first switch valve and opening the second switch valve; the second mode is a mode in which the refrigeration system needs to refrigerate when the outdoor environment temperature is within a second preset temperature range. The second predetermined temperature range may be selected from 0 ℃ to-15 ℃, but is not limited thereto, and the manufacturer may set the second predetermined temperature range according to actual requirements.

After the step of determining the current operating mode of the refrigeration system, the method further comprises: and if the current working mode is determined to be the third mode, closing the electronic expansion valve, closing the first switch valve, opening the second switch valve and starting the heating function of the heating device. The third mode is a mode in which the refrigeration system needs to refrigerate when the outdoor environment temperature is within a third preset temperature range. The third preset temperature range may be selected from-15 ℃ to-25 ℃, but is not limited thereto, and a manufacturer may set the third preset temperature range according to actual requirements.

The control method provided by the embodiment avoids the sudden drop of the indoor temperature when the refrigeration system is in the defrosting mode by controlling the refrigeration system 100, avoids the sudden drop of the indoor temperature when the refrigeration system is in the defrosting mode, avoids the discomfort caused by the overlarge temperature variation of a user, and can preheat the refrigerant when the ambient temperature is too low, so that the outdoor fan does not need to enter the anti-freezing protection mode due to the excessive frosting, further avoids the frequent start and stop of the outdoor fan, and prolongs the service life of the outdoor fan. The refrigerant can be cooled by controlling the opening degree of the electronic expansion valve, so that the problem that the compressor is lowered in frequency due to overhigh temperature of the refrigerant is solved.

Example 2

Embodiment 2 is substantially the same as embodiment 1 in terms of technical means, and therefore embodiment 2 will be described only with respect to differences therebetween.

In embodiment 1, the first switching valve 180 and the second switching valve 190 are provided, so that the refrigeration system can adjust the two switching valves according to different modes.

In embodiment 2, as shown in fig. 6, the first switching valve 180 and the second switching valve 190 are not provided. Specifically, in the present embodiment, for the purpose of saving the manufacturing cost of the manufacturer, the heating apparatus 170 is disposed on the route through which the refrigerant circulates, that is, the heating apparatus 170 stores the refrigerant in each mode, which reduces the heat exchange ratio of the refrigerant in the normal heating mode and the normal cooling mode, but the manufacturing cost can be greatly reduced by such a design. Especially in extreme environments (e.g., some regions where the ambient temperature is always low during the year), since the cooling system does not need to be equipped with the normal heating mode and the normal cooling mode, the heat supply device 170 is not lowered in the heat exchange ratio of the refrigerant when it is disposed on the necessary path of the refrigerant. Meanwhile, the first switching valve 180 and the second switching valve 190 do not need to be additionally arranged for the refrigeration system, so that the cost of the refrigeration system can be greatly reduced.

The refrigeration system and the control method provided by the embodiment of the present application are described in detail above, and the principle and the implementation of the present application are explained in the present application by applying specific examples, and the description of the above embodiment is only used to help understanding the technical solution and the core idea of the present application; those of ordinary skill in the art will understand that: the technical solutions described in the foregoing embodiments may still be modified, or some technical features may be equivalently replaced; such modifications or substitutions do not depart from the spirit and scope of the present disclosure as defined by the appended claims.

Claims

1. The utility model provides a refrigerating system, includes compressor, cross valve, first heat exchanger, throttle part and the second heat exchanger that connects gradually, its characterized in that, refrigerating system still includes:

the electronic expansion valve is respectively connected with the air return pipe of the compressor and the throttling component and is used for adjusting the opening degree of the electronic expansion valve according to different modes of the refrigeration system; and

and the heat supply device is respectively connected with the throttling component and the second heat exchanger and is used for storing the refrigerant and/or heating the refrigerant.

2. The refrigeration system as recited in claim 1 wherein when switching to the first mode of the refrigeration system, the heating means begins heating, and the electronic expansion valve adjusts its opening in real time based on the refrigerant temperature to reduce the temperature of the refrigerant entering the compressor.

3. The refrigerant system as set forth in claim 1, wherein said electronic expansion valve is closed when switching to the second mode of the refrigerant system, and said heating means is adapted to store a portion of refrigerant.

4. The refrigerant system as set forth in claim 1, further including:

the first switch valve is respectively connected with the throttling component and the second heat exchanger and is used for being opened or closed according to different modes of the refrigeration system; and

the second switch valve is respectively connected with the heating device and the second heat exchanger and is used for being opened or closed according to different modes of the refrigeration system;

the second switch valve and the heat supply device are arranged in series and are arranged in parallel with the first switch valve.

5. The refrigeration system as claimed in claim 4, wherein when switching to the first mode of the refrigeration system, the first switching valve is closed, the second switching valve is opened, the heating apparatus starts heating, and the electronic expansion valve adjusts its opening degree in real time according to the refrigerant temperature to lower the temperature of the refrigerant introduced into the compressor.

6. A control method for a refrigeration system as set forth in claim 1, wherein said control method comprises:

starting the heating function of the heating device;

judging whether the real-time numerical value of the refrigerant in the muffler of the compressor is within a preset range or not; the real-time value is a temperature value and/or a dryness value of the refrigerant;

and if the real-time numerical value of the refrigerant in the muffler of the compressor is judged not to be in the preset range, adjusting the self opening of the electronic expansion valve in real time.

7. The control method according to claim 6, wherein in the step of determining whether the real-time value of the refrigerant in the return pipe of the compressor is within a preset range, the adjustment of the opening degree of the electronic expansion valve is stopped if the real-time value of the refrigerant in the return pipe of the compressor is determined to be within the preset range.

8. The control method according to claim 7, characterized by, before the step of activating the heating function of the heating apparatus, comprising:

determining a current operating mode of the refrigeration system;

if the current working mode is determined to be the first mode, executing the step of starting the heating function of the heating device; the first mode is a mode in which the refrigeration system needs to heat when the outdoor environment temperature is within a first preset temperature range.

9. The control method as set forth in claim 8, wherein after said step of determining a current operating mode of the refrigerant system, the control method further includes: if the current working mode is determined to be the second mode, closing the electronic expansion valve, closing the first switch valve and opening the second switch valve; the second mode is a mode in which the refrigeration system needs to refrigerate when the outdoor environment temperature is within a second preset temperature range.

10. The control method as set forth in claim 8, wherein after said step of determining a current operating mode of the refrigerant system, the control method further includes: if the current working mode is determined to be the third mode, closing the electronic expansion valve, closing the first switch valve, opening the second switch valve and starting the heating function of the heating device; the third mode is a mode in which the refrigeration system needs to refrigerate when the outdoor environment temperature is within a third preset temperature range.