Cooling system

Abstract

A cooling system comprises a compressor, a condenser, a first throttling element and an evaporator, the exhaust side of the compressor communicates with the condenser, the condenser communicates with the throttling element, the throttling element communicates with the evaporator, and the evaporator communicates with the air suction side of the compressor; the heat regeneration branch comprises a first end and a second end, the first end communicates with the exhaust side of the compressor, and the second end communicates with the air suction side of the compressor; the heat regeneration branch comprises a second throttling element; according to the cooling system provided by the embodiment of the utility model, the heat return branch is arranged, so that high-temperature and high-pressure gaseous refrigerant on the exhaust side of the compressor can be introduced into the air suction side, the suction superheat degree of the compressor is improved, the problem that the compressor sucks liquid refrigerant is solved, and the risk that the compressor is impacted by liquid is reduced.

Description

Technical Field

[0001] The utility model relates to the technical field of heat dissipation, in particular to a cooling system. Background Art

[0002] In the field of energy storage direct cooling refrigeration and air conditioning, it is very important to ensure good temperature uniformity of the battery during cooling. In related technologies, this situation can be improved to a certain extent by increasing the flow rate of the refrigerant. However, after increasing the flow rate of the system refrigerant, it is easy for the compressor to inhale liquid, thereby causing liquid hammer problems in the compressor. Utility Model Content

[0003] The present utility model is based on the discovery and recognition of the following facts and problems by the utility model inventor:

[0004] The utility model aims to solve one of the technical problems in the related art to at least a certain extent. To this end, an embodiment of the utility model proposes a cooling system, including a compressor, a condenser, a first throttling element, and an evaporator, wherein the exhaust side of the compressor is connected to the condenser, the condenser is connected to the throttling element, the throttling element is connected to the evaporator, and the evaporator is connected to the suction side of the compressor;

[0005] It also includes a heat recovery branch, which includes a first end and a second end, the first end is connected to the exhaust side of the compressor, and the second end is connected to the suction side of the compressor; the heat recovery branch includes a second throttling element.

[0006] The cooling system of the embodiment of the utility model can introduce the high-temperature and high-pressure gaseous refrigerant on the exhaust side of the compressor into the suction side by setting a heat recovery branch, thereby increasing the suction superheat of the compressor, improving the problem of the compressor inhaling liquid refrigerant, and reducing the risk of the compressor being hit by liquid. BRIEF DESCRIPTION OF THE DRAWINGS

[0007] Figure 1 It is a schematic diagram of the utility model.

[0008] Figure numerals: 1. compressor; 2. condenser; 3. first throttling element; 4. evaporator; 41. cold plate; 5. heat recovery branch; 51. first end; 52. second end; 6. second throttling element; 7. first valve; 71. first port; 72. second port; 73. third port; 8. gas-liquid separator; 9. liquid separator; 10. flow meter; 101. first sensor; 102. second sensor. DETAILED DESCRIPTION

[0009] The embodiments of the present invention are described in detail below, and examples of the embodiments are shown in the accompanying drawings. The embodiments described below with reference to the accompanying drawings are exemplary and intended to be used to explain the present invention, but cannot be understood as limiting the present invention.

[0010] A cooling system comprises a compressor 1, a condenser 2, a first throttling element 3, and an evaporator 4, wherein the exhaust side of the compressor 1 is connected to the condenser 2, the condenser 2 is connected to the throttling element, the throttling element is connected to the evaporator 4, and the evaporator is connected to the suction side of the compressor 1;

[0011] It also includes a heat recovery branch 5, which includes a first end 51 and a second end 52. The first end 51 is connected between the exhaust side of the compressor 1 and the condenser 2, and the second end 52 is connected between the suction side of the compressor 1 and the evaporator 4; the heat recovery branch includes a second throttling element 6.

[0012] In the present embodiment, a direct cooling system for energy storage equipment is provided, which is different from the liquid cooling system in the related art. There is no heat exchange process of the coolant. The refrigerant is circulated in the cold plate 41, and the refrigerant absorbs heat through phase change. The battery is directly cooled and dissipated through the cold plate 41 to ensure the temperature of the battery. However, in some multi-connected energy storage devices, since the gasification of the refrigerant in the cold plate 41 is random, the surface of the cold plate 41 will have uneven temperature. For example, at the inlet of the cold plate 41, there is a large amount of refrigerant, and the refrigerant takes away the heat of the battery during the gasification process. Therefore, the temperature at the inlet of the cold plate 41 is relatively low. However, in the direction from the inlet to the outlet of the cold plate 41, the refrigerant will continue to gasify, resulting in less and less liquid refrigerant, a reduced amount of gasification, and reduced heat absorption, resulting in poor heat dissipation at the outlet of the cold plate 41, and the temperature is higher than the inlet. At the same time, since the gasification is random, there will be a relatively obvious temperature difference between different areas of the cold plate 41, which is not conducive to thermal management. Therefore, in order to solve the problem of temperature uniformity, in the present embodiment , the outlet superheat T1 of the cold plate 41 will be obtained through the first sensor 101. After testing, when T1 is less than 5 degrees, preferably 2 degrees, the refrigerant will not be completely gasified in the cold plate 41, and the gas-liquid mixed state will still be maintained. In this state, the mixed refrigerant can be more evenly distributed in various areas of the cold plate 41, and the temperature uniformity of the cold plate 41 is better. If T1 is within the range of [0,5] degrees, the current opening of the first throttling element 3 is maintained. When T1 is greater than 5 degrees, the opening of the first throttling element 3 needs to be increased. When the speed of compressor 1 is increased, the refrigerant flow rate in the system is increased, the amount of refrigerant in the cold plate 41 is increased, and then a large amount of refrigerant absorbs heat and vaporizes, but part of the liquid is still retained at the outlet of the cold plate 41. At the same time, the outlet superheat returns to the range of [0,5] degrees, thereby ensuring the uniformity of the temperature of the cold plate 41; however, in this case, liquid refrigerant will be retained on the low-pressure side of the system, resulting in the risk of liquid hammer in compressor 1. Therefore, the suction superheat of compressor 1 needs to be increased to more than 5 degrees to ensure that the refrigerant is completely gasified.

[0013] In this embodiment, a heat recovery branch 5 is provided, and the heat recovery branch 5 includes a first end 51 and a second end 52. The first end 51 is connected between the exhaust side of the compressor 1 and the condenser 2, and the second end 52 is connected between the suction side of the compressor 1 and the evaporator 4; the heat recovery branch includes a second throttling element 6; the refrigerant on the exhaust side of the compressor 1 is a high-temperature and high-pressure gaseous refrigerant, which enters the suction side of the compressor 1 after being reduced in pressure by the first throttling element 3. In this embodiment, the first throttling element 3 is a capillary tube, which has lower cost, convenient installation and maintenance, and high reliability. In other embodiments, the first throttling element 3 can be an expansion valve; the high-temperature and high-pressure gaseous refrigerant becomes a low-pressure and high-temperature gas after passing through the capillary tube, which can be neutralized and offset with the refrigerant on the suction side of the compressor 1, thereby increasing the superheat of the refrigerant, causing the liquid refrigerant on the suction side of the compressor 1 to heat up and vaporize, thereby reducing the risk of liquid hammering of the compressor 1.

[0014] In this embodiment, the first end 51 is provided with a first valve 7, and the first valve 7 includes a first port 71, which is connected to the exhaust side of the compressor 1; it also includes a second port 72, which is connected to the condenser 2, and also includes a third port 73, which is connected to the second throttling element 6; the first valve 7 is a proportional control valve, which can adjust the opening degree, and then control the amount of high-temperature and high-pressure refrigerant passing through the heat recovery branch 5, and adjust according to the superheat data of the second sensor 102, which is conducive to more refined control.

[0015] In this embodiment, a gas-liquid separator 8 is also included, and the gas-liquid separator 8 is connected between the evaporator 4 and the suction side of the compressor 1; the gas-liquid separator 8 can preliminarily separate the gaseous refrigerant and the liquid refrigerant, reducing the risk of the liquid refrigerant being sucked into the compressor 1.

[0016] In this embodiment, the second throttling element 6 is connected between the gas-liquid separator 8 and the suction side of the compressor 1; the high-temperature and high-pressure gaseous refrigerant discharged by the second throttling element 6 can partially increase the suction superheat, reduce the liquid refrigerant, and reduce the risk of liquid hammer of the compressor 1.

[0017] In this embodiment, a liquid separator 9 is also included, and the evaporator 4 includes at least two cold plates 41, and at least two cold plates 41 are connected to the liquid separator 9; in the case of a multi-split unit, the evaporator 4 includes a plurality of cold plates 41 connected in parallel. In order to ensure that the refrigerant distributed to each cold plate 41 is uniform, a liquid separator 9 is provided, which can evenly distribute the refrigerant, so that different cold plates 41 are distributed with equal refrigerant, thereby improving the temperature uniformity between different cold plates 41.

[0018] In this embodiment, the number of first throttling elements 3 corresponds to the number of cold plates 41, and the first throttling elements 3 are arranged between the cold plates 41 and the liquid distributor 9. In actual use, the heat generation of different energy storage batteries is not the same. Therefore, the first throttle valve is arranged between the cold plate 41 and the liquid distributor 9, and a throttling element is separately provided for each group of batteries. The opening of each first throttling element 3 can be adjusted separately according to the heating conditions of each group of batteries and the corresponding cold plates 41, so that the control is more precise and the temperature uniformity is better.

[0019] In summary, this embodiment also includes a flow meter 10. The number of flow meters 10 corresponds to the number of cold plates 41. The flow meter 10 is connected between the liquid distributor 9 and the first throttling element 3. Through the flow meter 10, the required flow of each group of cold plates 41 can be known more accurately, data visualization can be achieved, and at the same time, the adjustment is more precise.

[0020] In this embodiment, a first sensor 101 is further included. The first sensor 101 can obtain the outlet superheat T1 of the cold plate 41. The first sensor 101 can be a temperature and pressure sensor, which belongs to the prior art and will not be described in detail here.

[0021] In this embodiment, a second sensor 102 is also included. The second sensor 102 can obtain the suction superheat T2 of the compressor 1. The second sensor 102 can be a temperature and pressure sensor, which belongs to the existing technology and will not be described here.

[0022] In this embodiment, a fluorine pump 11 is also included. The fluorine pump 11 is connected between the condenser 2 and the liquid separator 9. The fluorine pump 11 can work in conjunction with the compressor 1. The fluorine pump 11 can increase the flow rate of the liquid refrigerant in the system, thereby increasing the proportion of the liquid refrigerant in the cold plate 41, which is more conducive to achieving temperature uniformity.

[0023] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", "circumferential" and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present invention.

[0024] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include at least one of the features. In the description of the present utility model, the meaning of "plurality" is at least two, such as two, three, etc., unless otherwise clearly and specifically defined.

[0025] In the present invention, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral one; it can be a mechanical connection, an electrical connection, or communication with each other; it can be a direct connection, or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements, unless otherwise clearly defined. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0026] In the present utility model, unless otherwise clearly specified and limited, a first feature being "above" or "below" a second feature may mean that the first and second features are in direct contact, or the first and second features are in indirect contact through an intermediate medium. Moreover, a first feature being "above", "above" or "above" a second feature may mean that the first feature is directly above or obliquely above the second feature, or simply means that the first feature is higher in level than the second feature. A first feature being "below", "below" or "below" a second feature may mean that the first feature is directly below or obliquely below the second feature, or simply means that the first feature is lower in level than the second feature.

[0027] In the present utility model, the terms "one embodiment", "some embodiments", "examples", "specific examples", or "some examples" etc. mean that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present utility model. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the described specific features, structures, materials or characteristics may be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art may combine and combine the different embodiments or examples described in this specification and the features of the different embodiments or examples, without contradiction.

[0028] Although the above embodiments have been shown and described, it is to be understood that the above embodiments are illustrative and cannot be construed as limitations on the present invention. Changes, modifications, substitutions and variations of the above embodiments by those of ordinary skill in the art are all within the scope of protection of the present invention.

Claims

1. A cooling system, characterized in that: include A compressor (1), a condenser (2), a first throttling element (3), and an evaporator (4), wherein the exhaust side of the compressor (1) is connected to the condenser (2), the condenser (2) is connected to the first throttling element (3), the first throttling element (3) is connected to the evaporator (4), and the evaporator (4) is connected to the suction side of the compressor (1); The invention also comprises a heat recovery branch (5), wherein the heat recovery branch (5) comprises a first end (51) and a second end (52), wherein the first end (51) is connected to the exhaust side of the compressor (1), and the second end (52) is connected to the intake side of the compressor (1); the heat recovery branch (5) comprises a second throttling element (6).

2. The cooling system according to claim 1, characterized in that: The first end (51) is provided with a first valve (7), the first valve (7) comprising a first port (71), the first port (71) being connected to the exhaust side of the compressor (1); a second port (72), the second port (72) being connected to the condenser (2); and a third port (73), the third port (73) being connected to the second throttling element (6).

3. The cooling system according to claim 2, characterized in that: It also includes a gas-liquid separator (8), which is connected between the evaporator (4) and the suction side of the compressor (1).

4. The cooling system according to claim 3, characterized in that: The second throttling element (6) is connected between the gas-liquid separator (8) and the suction side of the compressor (1).

5. The cooling system according to claim 2, characterized in that: It also comprises a liquid separator (9), wherein the evaporator (4) comprises at least two cold plates (41), and at least two of the cold plates (41) are connected to the liquid separator (9).

6. The cooling system according to claim 5, characterized in that: The number of the first throttling elements (3) corresponds to the number of the cold plates (41), and the first throttling elements (3) are arranged between the cold plates (41) and the liquid distributor (9).

7. The cooling system according to claim 6, characterized in that: It also includes flow meters (10), the number of the flow meters (10) corresponds to the number of the cold plates (41), and the flow meters (10) are connected between the liquid distributor (9) and the first throttling element (3).

8. The cooling system according to claim 5, characterized in that: It also includes a first sensor (101), wherein the first sensor (101) can obtain the outlet superheat T1 of the cold plate (41).

9. The cooling system according to claim 8, characterized in that: The compressor also includes a second sensor (102), wherein the second sensor (102) is capable of acquiring a suction superheat T2 of the compressor (1).

10. The cooling system according to any one of claims 5 to 9, characterized in that: It also includes a fluorine pump (11), which is connected between the condenser (2) and the liquid separator (9).

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