Refrigerant circulation system, refrigeration equipment, and control method of refrigerant circulation system

Abstract

The present invention relates to a refrigerant circulation system, refrigeration equipment and a control method for the refrigerant circulation system. The refrigerant circulation system comprises: a first compressor (1); a first condenser (3) connected to the exhaust port of the first compressor (1); a first throttling component (6) connected to the outlet of the first condenser (3); a second throttling component (7) connected to the outlet of the first condenser (3) and connected in parallel with the first throttling component (6); a first evaporator (8) comprising an inlet that can be selectively connected to one of the first throttling component (6) and the second throttling component (7) and an outlet connected to the air intake port of the first compressor (1). When one of the first throttling component (6) and the second throttling component (7) is blocked, the first evaporator (8) can be switched to be connected to the other one, thereby improving the problem of abnormal operation of the refrigerant circulation system caused by blockage of the throttling component in the prior art.

Description

Technical Field

[0001] The present invention relates to the field of refrigeration technology, and in particular to a refrigerant circulation system, a refrigeration device and a control method for the refrigerant circulation system. Background Art

[0002] For low-temperature refrigeration products, especially low-temperature refrigeration systems that use multi-stage refrigeration cycles, the lubricating oil in the system is difficult to flow due to the decrease in temperature and the increase in viscosity. When the compressor stops, the pressure difference at both ends of the capillary gradually disappears, and the temperature reaches the pour point of the lubricating oil, which is prone to accumulation and condensation of the lubricating oil. In addition, the lubricating oil easily absorbs moisture, and the water content of the system is difficult to effectively control within a low range. In a low-temperature environment, condensation will occur to form ice crystals. For this reason, an oil separator is set at the exhaust outlet of the compressor to reduce the oil content in the refrigerant; a dry filter is set at the front of the capillary to absorb the moisture in the refrigerant. However, the oil separator does not separate the lubricating oil 100%, and there is always a small amount of lubricating oil participating in the circulation. The lubricating oil participating in the circulation may cause the throttling component to be blocked. Failure of the dry filter may also cause the throttling component to be blocked, causing abnormal operation of the refrigeration system. Summary of the invention

[0003] The present invention aims to provide a refrigerant circulation system, a refrigeration device and a control method for the refrigerant circulation system, so as to improve the problem in the prior art that the refrigerant circulation system operates abnormally due to blockage of a throttling component.

[0004] According to one aspect of an embodiment of the present invention, the present invention provides a refrigerant circulation system, the refrigerant circulation system comprising:

[0005] The refrigerant circulation system, in some embodiments, includes:

[0006] The first compressor;

[0007] a first condenser connected to an exhaust port of the first compressor;

[0008] a first throttling component connected to an outlet of the first condenser;

[0009] a second throttling component connected to the outlet of the first condenser and connected in parallel with the first throttling component;

[0010] The first evaporator is connected to the first throttling component to introduce the throttled refrigerant and is configured to switch to being connected to the second throttling component to introduce the throttled refrigerant after the first throttling component is blocked.

[0011] In some embodiments, the refrigerant circulation system further comprises:

[0012] a first control valve having a first state for communicating the first evaporator with the first throttle member and a second state for communicating the first evaporator with the second throttle member;

[0013] a temperature detection component configured to detect a temperature of the refrigerant introduced into the inlet of the first evaporator or a temperature of the refrigerant discharged from the outlet of the first evaporator; and

[0014] The controller is signal-connected to the first control valve and the temperature detection component respectively, and is configured to control the switching state of the first control valve when the temperature detected by the temperature detection component meets a predetermined condition.

[0015] In some embodiments,

[0016] The predetermined conditions include that the temperature Te of the refrigerant output from the outlet of the first evaporator is greater than the reference temperature Tx and / or the temperature rise of the refrigerant output from the first evaporator lasts for a predetermined time and / or the temperature rise of the refrigerant output from the first evaporator per unit time is higher than a preset value; and / or

[0017] The predetermined conditions include that the temperature of the refrigerant to be introduced into the first evaporator drops to a predetermined temperature and / or the temperature reduction rate of the refrigerant to be introduced into the first evaporator reaches a predetermined speed and / or the temperature reduction amplitude of the refrigerant to be introduced into the first evaporator per unit time is higher than a preset value.

[0018] In some embodiments, the reference temperature Tx includes the temperature of an environment exchanging heat with the first evaporator.

[0019] In some embodiments, the refrigerant circulation system further comprises:

[0020] The first heat exchange pipeline is used for circulating the refrigerant that heats the first throttling component when the first evaporator is connected to the second throttling component; and / or

[0021] The second heat exchange pipeline is used for circulating the refrigerant that heats the second throttling component when the first evaporator is connected to the first throttling component.

[0022] In some embodiments, the refrigerant circulation system further includes a second compressor and a second condenser connected to an exhaust port of the second compressor, and the first heat exchange pipeline and the second heat exchange pipeline are respectively connected to an outlet of the second condenser.

[0023] In some embodiments, the refrigerant circulation system further comprises:

[0024] a second control valve having a first state for connecting the second condenser to the first heat exchange pipeline and a second state for connecting the second condenser to the second heat exchange pipeline;

[0025] a temperature detection component configured to detect a temperature of the refrigerant introduced into the inlet of the first evaporator or a temperature of the refrigerant discharged from the outlet of the first evaporator; and

[0026] The controller is signal-connected to the second control valve and the temperature detection component respectively, and is configured to control the switching state of the first control valve when the temperature detected by the temperature detection component meets a predetermined condition.

[0027] In some embodiments, the refrigerant circulation system further includes a second evaporator, the inlet of the second evaporator is connected to the second condenser, the outlet of the second evaporator is connected to the suction port of the second compressor, and the second evaporator is configured to exchange heat with the first condenser.

[0028] In some embodiments, the refrigerant circulation system includes a first branch and a second branch respectively connected to the first condenser, the first heat exchange pipe and the second throttling component are connected in series in the first branch, and the second heat exchange pipe and the first throttling component are connected in series in the second branch.

[0029] In some embodiments, on the refrigerant flow path, the first heat exchange pipeline is located upstream of the second throttling component; on the refrigerant flow path, the second heat exchange pipeline is located upstream of the first throttling component.

[0030] According to another aspect of the present invention, a refrigeration device is provided. The refrigeration device includes the above-mentioned refrigerant circulation system.

[0031] In some embodiments, the refrigeration device comprises a medical refrigerator.

[0032] According to another aspect of the present invention, a control method for the above-mentioned refrigerant circulation system is also provided, and the control method comprises:

[0033] detecting the temperature of the refrigerant introduced into the inlet of the first evaporator or the temperature of the refrigerant discharged from the outlet of the first evaporator;

[0034] If the detected temperature satisfies a predetermined condition, the first evaporator is switched from being connected to the first throttling component to being connected to the second throttling component.

[0035] In some embodiments,

[0036] The predetermined conditions include that the temperature Te of the refrigerant output from the outlet of the first evaporator is greater than the reference temperature Tx and / or the temperature rise of the refrigerant output from the first evaporator lasts for a predetermined time and / or the temperature rise of the refrigerant output from the first evaporator per unit time is higher than a preset value; and / or

[0037] The predetermined conditions include that the temperature of the refrigerant to be introduced into the first evaporator drops to a predetermined temperature and / or the temperature reduction rate of the refrigerant to be introduced into the first evaporator reaches a predetermined speed and / or the temperature reduction amplitude of the refrigerant to be introduced into the first evaporator per unit time is higher than a preset value.

[0038] In some embodiments, the reference temperature Tx includes the temperature of an environment exchanging heat with the first evaporator.

[0039] By applying the technical solution of the present application, when one of the first throttling component and the second throttling component is blocked, the first evaporator can be switched to be connected to the other one, thereby improving the problem of abnormal operation of the refrigerant circulation system caused by blockage of the throttling component in the prior art.

[0040] Further features and advantages of the present invention will become apparent from the following detailed description of exemplary embodiments of the present invention with reference to the attached drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0041] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative labor.

[0042] Figure 1 A schematic diagram showing the structure of a refrigerant circulation system in some embodiments of the present invention is shown;

[0043] Figure 2 A control flow chart showing a refrigerant circulation system of some embodiments of the present invention; and

[0044] Figure 3 The schematic diagrams of structures of refrigerant circulation systems of other embodiments of the present invention are shown.

[0045] In the figure: 1. first compressor; 2. oil separator; 3. first condenser; 4. first filter drier; 5. first control valve; 6. first throttling component; 7. second throttling component; 8. first evaporator; 9. temperature detection component; 10. first heat exchange pipeline; 11. second heat exchange pipeline; 12. second control valve; 13. second compressor; 14. second condenser; 15. second filter drier; 16. third throttling component; 17. second evaporator. DETAILED DESCRIPTION

[0046] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all the embodiments. The following description of at least one exemplary embodiment is actually only illustrative and is by no means intended to limit the present invention and its application or use. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0047] Combination Figure 1 and Figure 2 As shown, the refrigerant circulation system of this embodiment includes a first compressor 1, a first condenser 3, a first throttling component 6, a second throttling component 7 and a first evaporator 8.

[0048] The first condenser 3 is connected to the exhaust port of the first compressor 1; the first throttling component 6 is connected to the outlet of the first condenser 3; the second throttling component 7 is connected to the outlet of the first condenser 3 and is connected in parallel with the first throttling component 6; the first evaporator 8 is connected to the first throttling component 6 to introduce the throttled refrigerant and is configured to switch to the second throttling component 7 to introduce the throttled refrigerant after the first throttling component 6 is blocked.

[0049] In this embodiment, when one of the first throttling component 6 and the second throttling component 7 is blocked, the first evaporator 8 can be switched to be connected to the other one, thereby improving the problem of abnormal operation of the refrigerant circulation system caused by blockage of the throttling component in the prior art.

[0050] The refrigerant circulation system also includes an oil separator 2 connected to the outlet of the first compressor 1 , and the oil separator 2 includes an inlet connected to the exhaust port of the first compressor 1 , a lubricating oil outlet connected to the suction port of the first compressor 1 , and a refrigerant outlet connected to the first condenser 3 .

[0051] In some embodiments, the refrigerant circulation system further includes a first drying filter 4 , the inlet of the first drying filter 4 is connected to the outlet of the first condenser 3 , and the first throttling component 5 and the second throttling component 7 are respectively connected to the outlet of the first drying filter 4 .

[0052] The refrigerant circulation system further includes a first control valve 5, a temperature detection component 9 and a controller. The first control valve 5 has a first state in which the first evaporator 8 is connected to the first throttling component 6 and a second state in which the first evaporator 8 is connected to the second throttling component 7; the temperature detection component 9 is configured to detect the temperature of the refrigerant introduced into the inlet of the first evaporator 8 or the temperature of the refrigerant discharged from the outlet of the first evaporator 8; the controller is signal-connected to the first control valve 5 and the temperature detection component 9, respectively, and is configured to control the switching state of the first control valve 5 when the temperature detected by the temperature detection component 9 meets a predetermined condition.

[0053] In this embodiment, the temperature detected by the temperature detection component 9 is used to determine whether the throttling component connected to the first evaporator 8 in a working state is blocked. After the throttling component connected to the first evaporator 8 is blocked, the first evaporator 8 is switched to be connected to another throttling component to introduce the throttled refrigerant.

[0054] The first control valve 5 includes an inlet a connected to the outlet of the first condenser 3, a first outlet b connected to the first throttle member 6, and a second outlet c connected to the second throttle member 7. The first control valve 5 has a first state in which the inlet a communicates with the first outlet b and a second state in which the inlet a communicates with the second outlet c.

[0055] After the throttling component is blocked, the amount of refrigerant entering the first evaporator 8 decreases, the refrigeration capacity of the first evaporator 8 deteriorates, and the temperature of the refrigerant output by the first evaporator 8 increases. In some embodiments, the predetermined condition includes that the temperature Te of the refrigerant output from the outlet of the first evaporator 8 is greater than the reference temperature Tx and the temperature increase of the refrigerant output from the first evaporator 8 lasts for a predetermined time. In other embodiments, the predetermined condition includes that the temperature Te of the refrigerant output from the outlet of the first evaporator 8 is greater than the reference temperature Tx and the temperature increase of the refrigerant output from the first evaporator 8 per unit time is higher than a preset value.

[0056] In other embodiments, the temperature detection component 9 is located upstream of the first evaporator 8 and downstream of the first throttling component 6 and the second throttling component 7 in the refrigerant flow direction. Since, after the throttling component is blocked, the pressure in the pipeline downstream of the throttling component and upstream of the first evaporator 8 decreases, the refrigerant evaporates more fully, and thus the temperature of the refrigerant is lower. The predetermined conditions include that the temperature of the refrigerant to be introduced into the first evaporator 8 is reduced to a predetermined temperature and / or the temperature reduction rate of the refrigerant to be introduced into the first evaporator 8 reaches a predetermined speed and / or the temperature of the refrigerant to be introduced into the first evaporator 8 is reduced by more than a preset value per unit time.

[0057] In some embodiments, the reference temperature Tx is the temperature of the environment exchanging heat with the first evaporator 8 .

[0058] The refrigerant circulation system further includes a first heat exchange pipeline 10 and a second heat exchange pipeline 11. The first heat exchange pipeline 10 is used to circulate the refrigerant that heats the first throttling component 6 when the first evaporator 8 is connected to the second throttling component 7; the second heat exchange pipeline 11 is used to circulate the refrigerant that heats the second throttling component 7 when the first evaporator 8 is connected to the first throttling component 6.

[0059] like Figure 1 As shown, in some embodiments, the refrigerant circulation system further includes a second compressor 13 and a second condenser 14 connected to the exhaust port of the second compressor 13, and the first heat exchange pipeline 10 and the second heat exchange pipeline 11 are respectively connected to the outlet of the second condenser 14.

[0060] The refrigerant circulation system further includes a second control valve 12. The second control valve 12 has a first state in which the second condenser 14 is connected to the first heat exchange pipeline 10 and a second state in which the second condenser 14 is connected to the second heat exchange pipeline 11.

[0061] The controller is signal-connected to the second control valve 12 and the temperature detection component 9 respectively, and is configured to control the switching state of the second control valve 12 when the temperature detected by the temperature detection component 9 meets the above-mentioned predetermined condition.

[0062] The second control valve 12 includes an inlet a connected to the outlet of the second condenser 14, a first outlet b connected to the second heat exchange pipeline 11, and a second outlet c connected to the first heat exchange pipeline 10. The second control valve 12 has a first state in which the inlet a is connected to the first outlet b and a second state in which the inlet a is connected to the second outlet c.

[0063] The refrigerant circulation system further includes a second evaporator 17 , an inlet of the second evaporator 17 is connected to the second condenser 14 , an outlet of the second evaporator 17 is connected to the air intake of the second compressor 13 , and the second evaporator 17 is configured to exchange heat with the first condenser 3 .

[0064] The refrigerant circulation system further includes a third throttling component 16 and a second drying filter 15. The inlet of the third throttling component 16 is connected to the outlet of the second condenser 14, and the outlet of the third throttling component 16 is connected to the inlet of the second evaporator 17. The second drying filter 15 is located between the second condenser 14 and the third throttling component 16 on the refrigerant flow path.

[0065] like Figure 3 Another optional embodiment of the present application, this embodiment is Figure 1 The difference of the embodiment shown is that after one of the first throttle component 6 and the second throttle component 7 in the working state is blocked, the first evaporator 8 is switched to the other connection to allow the refrigerant circulation system to operate normally. At the same time, the blocked throttle component is heated to improve the fluidity of the lubricating oil blocking the throttle component or melt the ice blocking the throttle component, so that the blocked throttle component can be unblocked again.

[0066] For example, at the initial stage of system operation, the first control valve 5 and the second control valve 12 are both in the first state, the refrigerant output by the first condenser 3 flows to the first throttling component 6, and the second condenser 14 is connected to the second heat exchange pipeline 11. After the system has been running for a period of time, if the temperature detected by the temperature detection component 9 meets the above-mentioned predetermined conditions, the first control valve 5 and the second control valve 12 are switched to the second state, the refrigerant output by the first condenser 3 flows to the second throttling component 7, and the second condenser 14 is connected to the first heat exchange pipeline 10. Then the system continues to move, and if the temperature detected by the temperature detection component 9 again meets the above-mentioned predetermined conditions, the first control valve 5 and the second control valve 12 are switched to the first state.

[0067] like Figure 2As shown, in other embodiments, the refrigerant circulation system includes a first branch and a second branch respectively connected to the first condenser 3, the first heat exchange pipeline 10 and the second throttling component 7 are connected in series in the first branch, and the second heat exchange pipeline 11 and the first throttling component 6 are connected in series in the second branch.

[0068] On the refrigerant flow path, the first heat exchange pipeline 10 is located upstream of the second throttling component 7 ; on the refrigerant flow path, the second heat exchange pipeline 11 is located upstream of the first throttling component 6 .

[0069] According to another aspect of the present invention, a refrigeration device is further provided, which in some embodiments includes the above-mentioned refrigerant circulation system.

[0070] In some embodiments, the refrigeration device comprises a medical refrigerator.

[0071] According to another aspect of the present invention, a control method for the above-mentioned refrigerant circulation system is also provided, and the control method comprises:

[0072] Detecting the temperature of the refrigerant introduced into the inlet of the first evaporator 8 or the temperature of the refrigerant discharged from the outlet of the first evaporator 8;

[0073] If the detected temperature satisfies a predetermined condition, the first evaporator 8 is switched from being connected to the first throttling component 6 to being connected to the second throttling component 7 .

[0074] In some embodiments,

[0075] The predetermined conditions include that the temperature Te of the refrigerant output from the outlet of the first evaporator 8 is greater than the reference temperature Tx and / or the temperature rise of the refrigerant output from the first evaporator 8 lasts for a predetermined time and / or the temperature rise of the refrigerant output from the first evaporator 8 per unit time is higher than a preset value; and / or

[0076] The predetermined conditions include that the temperature of the refrigerant to be introduced into the first evaporator 8 drops to a predetermined temperature and / or the temperature reduction rate of the refrigerant to be introduced into the first evaporator 8 reaches a predetermined speed and / or the temperature reduction amplitude of the refrigerant to be introduced into the first evaporator 8 per unit time is higher than a preset value.

[0077] In some embodiments, the reference temperature Tx includes the temperature of an environment exchanging heat with the first evaporator 8 .

[0078] The above are merely exemplary embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A refrigerant circulation system, characterized in that: include: A first compressor (1); A first condenser (3) connected to an exhaust port of the first compressor (1); A first throttling component (6) connected to an outlet of the first condenser (3); a second throttling component (7) connected to the outlet of the first condenser (3) and connected in parallel with the first throttling component (6); A first evaporator (8) is connected to the first throttling component (6) to introduce throttled refrigerant and is configured to switch to being connected to the second throttling component (7) to introduce throttled refrigerant after the first throttling component (6) is blocked, A first heat exchange pipeline (10) is used for circulating a refrigerant for heating the first throttling component (6) when the first evaporator (8) is connected to the second throttling component (7); and / or The second heat exchange pipeline (11) is used for circulating a refrigerant for heating the second throttling component (7) when the first evaporator (8) is connected to the first throttling component (6). The refrigerant circulation system comprises a first branch and a second branch respectively connected to the first condenser (3); the first heat exchange pipeline (10) and the second throttling component (7) are connected in series in the first branch; and the second heat exchange pipeline (11) and the first throttling component (6) are connected in series in the second branch.

2. The refrigerant circulation system according to claim 1, characterized in that: Also includes: a first control valve (5) having a first state in which the first evaporator (8) is connected to the first throttling component (6) and a second state in which the first evaporator (8) is connected to the second throttling component (7); a temperature detection component (9) configured to detect the temperature of the refrigerant introduced into the inlet of the first evaporator (8) or the temperature of the refrigerant discharged from the outlet of the first evaporator (8); as well as A controller is signal-connected to the first control valve (5) and the temperature detection component (9) respectively, and is configured to control the first control valve (5) to switch its state when the temperature detected by the temperature detection component (9) meets a predetermined condition.

3. The refrigerant circulation system according to claim 2, characterized in that: The predetermined conditions include that the temperature Te of the refrigerant output from the outlet of the first evaporator (8) is greater than the reference temperature Tx and / or the temperature rise of the refrigerant output from the first evaporator (8) lasts for a predetermined time and / or the temperature rise of the refrigerant output from the first evaporator (8) per unit time is greater than a preset value; and / or The predetermined conditions include that the temperature of the refrigerant to be introduced into the first evaporator (8) drops to a predetermined temperature and / or the temperature reduction rate of the refrigerant to be introduced into the first evaporator (8) reaches a predetermined rate and / or the temperature reduction amplitude of the refrigerant to be introduced into the first evaporator (8) per unit time is higher than a preset value.

4. The refrigerant circulation system according to claim 3, characterized in that: The reference temperature Tx includes the temperature of the environment exchanging heat with the first evaporator (8).

5. The refrigerant circulation system according to claim 1, characterized in that: It also includes a second compressor (13) and a second condenser (14) connected to the exhaust port of the second compressor (13), and the first heat exchange pipeline (10) and the second heat exchange pipeline (11) are respectively connected to the outlet of the second condenser (14).

6. The refrigerant circulation system according to claim 5, characterized in that: Also includes: a second control valve (12) having a first state in which the second condenser (14) is connected to the first heat exchange pipeline (10) and a second state in which the second condenser (14) is connected to the second heat exchange pipeline (11); a temperature detection component (9) configured to detect the temperature of the refrigerant introduced into the inlet of the first evaporator (8) or the temperature of the refrigerant discharged from the outlet of the first evaporator (8); as well as A controller is signal-connected to the second control valve (12) and the temperature detection component (9), respectively, and is configured to control the second control valve (12) to switch state when the temperature detected by the temperature detection component (9) meets a predetermined condition.

7. The refrigerant circulation system according to claim 5, characterized in that: It also includes a second evaporator (17), the inlet of the second evaporator (17) is connected to the second condenser (14), the outlet of the second evaporator (17) is connected to the suction port of the second compressor (13), and the second evaporator (17) is configured to exchange heat with the first condenser (3).

8. The refrigerant circulation system according to claim 1, characterized in that: On the refrigerant flow path, the first heat exchange pipeline (10) is located upstream of the second throttling component (7); on the refrigerant flow path, the second heat exchange pipeline (11) is located upstream of the first throttling component (6).

9. A refrigeration device, characterized in that: A refrigerant circulation system comprising the refrigerant circulation system according to any one of claims 1 to 8.

10. The refrigeration device according to claim 9, characterized in that: Includes medical refrigerator.

11. A control method for a refrigerant circulation system according to any one of claims 1 to 8, characterized in that: include: detecting the temperature of the refrigerant introduced into the inlet of the first evaporator (8) or the temperature of the refrigerant discharged from the outlet of the first evaporator (8); If the detected temperature meets a predetermined condition, the first evaporator (8) is switched from being connected to the first throttling component (6) to being connected to the second throttling component (7).

12. The control method of the refrigerant circulation system according to claim 11, characterized in that: The predetermined conditions include that the temperature Te of the refrigerant output from the outlet of the first evaporator (8) is greater than the reference temperature Tx and / or the temperature rise of the refrigerant output from the first evaporator (8) lasts for a predetermined time and / or the temperature rise of the refrigerant output from the first evaporator (8) per unit time is greater than a preset value; and / or The predetermined conditions include that the temperature of the refrigerant to be introduced into the first evaporator (8) drops to a predetermined temperature and / or the temperature reduction rate of the refrigerant to be introduced into the first evaporator (8) reaches a predetermined rate and / or the temperature reduction amplitude of the refrigerant to be introduced into the first evaporator (8) per unit time is higher than a preset value.

13. The control method of the refrigerant circulation system according to claim 12, characterized in that: The reference temperature Tx includes the temperature of the environment exchanging heat with the first evaporator (8).

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