Refrigeration equipment, control method and control device thereof and storage medium

Abstract

The invention discloses refrigeration equipment, a control method and device thereof and a storage medium. The refrigeration equipment comprises a refrigeration system, the refrigeration system comprises a multi-stage compressor, a condenser, a throttling device and an evaporator which are sequentially connected end to end, the multi-stage compressor comprises a plurality of compression modules which are sequentially connected, at least one compression module comprises a compression unit and a cooler, and the cooler is located on the downstream side of the compression unit and communicates with the compression unit; each compression module comprises a compression unit; and the cooling system comprises a cooling flow path, the input end of the cooling flow path is connected to the evaporator and / or the condenser, the output end of the cooling flow path is connected to the cooler, and the cooling flow path is arranged to convey a cooling medium in the evaporator and / or the condenser to the cooler so as to reduce the superheat degree of a refrigerant discharged by the cooler. According to the scheme, the multi-stage compressor can be cooled by using the cooling medium in the system, and an external cooling circulating water system is not needed, so that the miniaturization of refrigeration equipment is facilitated, and the cost is reduced.

Description

Technical Field

[0001] The present application relates to but is not limited to the technical field of refrigeration equipment, and specifically refers to a refrigeration equipment and a control method, a control device and a computer-readable storage medium thereof. Background Art

[0002] At present, with the increasing attention paid to the depletion of the ozone layer and greenhouse gas issues at home and abroad, countries around the world have accelerated the pace of research and development of new refrigerants to solve the climate threat brought about by the growing market demand. In the centrifugal compressor water vapor refrigeration and air-conditioning industry, the size of the centrifugal compressor must be limited in the process of increasing the pressure ratio, which leads to the need to design multi-stage compression (i.e., multi-stage centrifugal compressor) for the centrifugal compressor. In the process of being compressed by the multi-stage centrifugal compressor, the pressure and temperature of the refrigerant continue to increase. The pressure increase is our demand, but the temperature is too high, which poses a major problem to the design and operation of the entire multi-stage centrifugal compressor. Therefore, the multi-stage centrifugal compressor needs to be cooled.

[0003] Currently, most commonly used cooling methods use an external cooling circulating water system for indirect cooling, which results in a large size of the overall unit and high cost. Summary of the invention

[0004] The technical problem to be solved by the present application is to provide a refrigeration device that can utilize the cooling medium in the system to cool a multi-stage compressor without the need for an external cooling circulating water system, thereby facilitating the miniaturization of the refrigeration device and reducing costs.

[0005] The technical solution for solving the above-mentioned technical problems in the embodiments of the present application is as follows: a refrigeration device, comprising: a refrigeration system, including a multi-stage compressor, a condenser, a throttling device and an evaporator connected in sequence end to end, the multi-stage compressor including a plurality of compression modules connected in sequence, at least one of the compression modules including a compression unit and a cooler, the cooler being located on the downstream side of the compression unit and connected to the compression unit, and each of the compression modules including the compression unit; and a cooling system, including a cooling flow path, the input end of the cooling flow path being connected to the evaporator and / or the condenser, the output end of the cooling flow path being connected to the cooler, and being configured to transport the cooling medium in the evaporator and / or the condenser to the cooler to reduce the superheat of the refrigerant discharged from the cooler.

[0006] The refrigeration equipment provided in the embodiment of the present application comprises a multi-stage compressor, a condenser, a throttling device and an evaporator connected end to end in sequence to form a refrigeration cycle. After the high-temperature and high-pressure refrigerant discharged from the multi-stage compressor enters the condenser for condensation, it is throttled and depressurized by the throttling device before entering the evaporator, where it evaporates and absorbs heat to become a gaseous refrigerant and flows back to the compressor. The evaporator can be an indoor heat exchanger, which absorbs indoor heat by evaporation and cools the room. The condenser can be an outdoor heat exchanger, which releases heat to the outdoor environment by condensation.

[0007] Since the refrigerant temperature in the evaporator and the refrigerant temperature in the condenser are both lower than the refrigerant temperature in the compressor, the embodiment of the present application utilizes a cooling flow path to transport the cooling medium in the evaporator and / or condenser to the cooler, and cools the refrigerant discharged from the compression unit adjacent to the upstream side of the cooler. The temperature of the refrigerant discharged after being cooled by the cooler is reduced, thereby reducing the superheat of the refrigerant discharged from the compression module including the compression unit and the cooler, and avoiding excessive superheat of the refrigerant and affecting the normal operation of the subsequent compression module and the refrigeration equipment. As a result, the refrigeration equipment can use the cooling medium in the system to cool the multi-stage compressor without the need for an external cooling source, which is beneficial to reducing the volume of the refrigeration equipment and reducing the cost of the refrigeration equipment.

[0008] Furthermore, in the embodiment of the present application, the input end of the cooling flow path can be connected to the evaporator and / or the condenser, and the cooling medium can be directly extracted from the evaporator and / or the condenser. Since the evaporator and the condenser are large in size and have a large amount of cooling medium inside, the effect of extracting a certain amount of cooling medium on the pressure of the refrigeration system is relatively small. However, if the input end of the cooling flow path is connected to the pipeline between the condenser and the evaporator, the effect on the pressure of the refrigeration system is relatively large, so this solution is conducive to improving the reliability of the refrigeration equipment.

[0009] Based on the above technical solution, the present application can also be improved as follows.

[0010] In an exemplary embodiment, the cooler is a direct cooler, and the direct cooler is configured to allow the refrigerant discharged from the compression unit to perform contact heat exchange with the cooling medium transported by the cooling flow path.

[0011] In an exemplary embodiment, the cooler is an indirect cooler, and a first heat exchange channel and a second heat exchange channel are provided in the indirect cooler, the first heat exchange channel is connected to the adjacent compression unit, and the output end of the cooling channel is connected to the input end of the second heat exchange channel; the cooling system also includes a return branch, the input end of the return branch is connected to the output end of the second heat exchange channel, and the output end of the return branch is connected to the evaporator and / or the condenser; the first heat exchange channel and the second heat exchange channel are configured to separate the refrigerant discharged from the compression unit from the cooling medium transported by the cooling channel, so that the refrigerant discharged from the compression unit and the cooling medium transported by the cooling channel can perform non-contact heat exchange.

[0012] In an exemplary embodiment, the indirect cooler is a phase change cooler; alternatively, the indirect cooler is a non-phase change cooler.

[0013] In an exemplary embodiment, each of the compression modules includes the compression unit and the cooler, and the cooling flow path includes a plurality of cooling branches connected in parallel, and the plurality of cooling branches are connected to the plurality of coolers in a one-to-one correspondence.

[0014] In an exemplary embodiment, the cooling system further includes: a control valve, disposed in the cooling flow path, configured to control the on / off state and / or working parameters of the cooling flow path.

[0015] In an exemplary embodiment, the refrigeration equipment further includes: a control device configured to adjust the control valve according to the superheat of the refrigerant discharged from the compression unit adjacent to the upstream side of the cooler, so that the superheat of the refrigerant discharged from the cooler is within a set superheat range.

[0016] In an exemplary embodiment, the cooling system further includes: a pump body, which is in communication with the cooling flow path and is configured to pump the cooling medium in the evaporator and / or the condenser to the cooler.

[0017] In an exemplary embodiment, an input end of the cooling flow path is connected to the bottom of the evaporator to transport the liquid cooling medium at the bottom of the evaporator to the cooler.

[0018] In an exemplary embodiment, the refrigeration system is a water refrigeration system, the compressor is a water vapor compressor, the cooling medium is water; and / or the refrigeration equipment is an air conditioner.

[0019] The present application also provides a control method, which is used for the refrigeration device as described in any one of the above embodiments, and the control method includes:

[0020] determining the superheat of the refrigerant discharged from the compression unit adjacent to the upstream side of the cooler;

[0021] The on / off state and / or working parameters of the cooling flow path are adjusted according to the superheat of the refrigerant discharged from the compression unit, so that the superheat of the refrigerant discharged from the cooler is within a set superheat range.

[0022] In an exemplary embodiment, each of the compression modules includes the compression unit and the cooler, the cooling flow path includes a plurality of cooling branches connected in parallel, and the plurality of cooling branches are connected to the plurality of coolers in a one-to-one correspondence; determining the superheat of the refrigerant discharged from the compression unit adjacent to the upstream side of the cooler includes: determining the superheat of the refrigerant discharged from the compression unit adjacent to the upstream side of each cooler; adjusting the on-off and / or working parameters of the cooling flow path according to the superheat of the refrigerant discharged from the compression unit so that the superheat of the refrigerant discharged from the cooler is within a set superheat range, includes: adjusting the on-off and / or working parameters of the corresponding cooling branch according to the superheat of the refrigerant discharged from each compression unit so that the superheat of the refrigerant discharged from each cooler is within a set superheat range.

[0023] An embodiment of the present application further provides a control device, including a processor and a memory storing a computer program, wherein the processor implements the steps of the control method described in the above embodiment when executing the computer program.

[0024] An embodiment of the present application further provides a computer-readable storage medium, comprising a computer program, wherein when the computer program is executed by a processor, the steps of the control method as described in the above embodiment are implemented. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 A schematic diagram of the structural principle of a refrigeration device provided in some embodiments of the present application;

[0026] Figure 2 A schematic diagram of the structural principle of a refrigeration device provided in some other embodiments of the present application;

[0027] Figure 3 A flow chart of a control method provided in some embodiments of the present application;

[0028] Figure 4 A schematic diagram of the principle of the control method provided by some embodiments of the present application;

[0029] Figure 5 A schematic diagram of the method principles of the control methods provided in other embodiments of the present application.

[0030] In the accompanying drawings, the components represented by the reference numerals are listed as follows:

[0031] 1 multi-stage compressor, 11 compression module, 12 compression unit, 121 primary compression unit, 122 secondary compression unit, 13 cooler, 131 primary cooler, 132 secondary cooler;

[0032] 2 condenser, 3 throttling device, 4 evaporator;

[0033] 51 cooling main circuit, 52 cooling branch circuit, 53 return branch circuit;

[0034] 6 Pump body;

[0035] 7 control valve, 71 first control valve, 72 second control valve.

[0036] in, Figure 1 and Figure 2 The arrows in the figure indicate the flow direction of the refrigerant / cooling medium. DETAILED DESCRIPTION

[0037] The principles and features of the present application are described below in conjunction with the accompanying drawings. The examples given are only used to explain the present application and are not used to limit the scope of the present application.

[0038] like Figure 1 and Figure 2 As shown, an embodiment of the present application provides a refrigeration device, including: a refrigeration system and a cooling system.

[0039] The refrigeration system includes a multi-stage compressor 1, a condenser 2, a throttling device 3 and an evaporator 4 connected in sequence end to end. The throttling device 3 can be but is not limited to an expansion valve. The multi-stage compressor 1 includes a plurality of compression modules 11 connected in sequence. At least one compression module 11 includes a compression unit 12 and a cooler 13, and the cooler 13 is located on the downstream side of the compression unit 12 and is connected to the compression unit 12. Each compression module 11 includes a compression unit 12. The compression unit 12 may include a compression chamber and an impeller arranged in the compression chamber, and the impeller may be driven by a motor.

[0040] The cooling system includes a cooling flow path. The input end of the cooling flow path is connected to the evaporator 4 and / or the condenser 2, and the output end of the cooling flow path is connected to the cooler 13, which is configured to transport the cooling medium in the evaporator 4 and / or the condenser 2 to the cooler 13 to reduce the superheat of the refrigerant discharged from the cooler 13.

[0041] The refrigeration equipment provided in the embodiment of the present application comprises a multi-stage compressor 1, a condenser 2, a throttling device 3 and an evaporator 4 which are connected end to end in sequence to form a refrigeration cycle. After the high-temperature and high-pressure refrigerant discharged from the multi-stage compressor 1 enters the condenser 2 for condensation, it is throttled and depressurized by the throttling device 3 and enters the evaporator 4, where it evaporates and absorbs heat to become a gaseous refrigerant and flows back to the compressor. The evaporator 4 can be an indoor heat exchanger, which absorbs indoor heat by evaporation and cools the room. The condenser 2 can be an outdoor heat exchanger, which releases heat to the outdoor environment by condensation.

[0042] Since the refrigerant temperature in the evaporator 4 and the refrigerant temperature in the condenser 2 are both lower than the refrigerant temperature in the compressor, the embodiment of the present application utilizes a cooling flow path to transport the cooling medium in the evaporator 4 and / or the condenser 2 to the cooler 13, and cools the refrigerant discharged from the compression unit 12 adjacent to the upstream side of the cooler 13. The temperature of the refrigerant discharged after being cooled by the cooler 13 is reduced, thereby reducing the superheat of the refrigerant discharged from the compression module 11 including the compression unit 12 and the cooler 13, and avoiding the refrigerant from being overheated and affecting the normal operation of the subsequent compression module 11 and the refrigeration equipment. As a result, the refrigeration equipment can use the cooling medium in the system to cool the multi-stage compressor 1 without the need for an external cooling source, which is conducive to reducing the volume of the refrigeration equipment and reducing the cost of the refrigeration equipment.

[0043] Furthermore, in the embodiment of the present application, the input end of the cooling flow path can be connected to the evaporator 4 and / or the condenser 2, and the cooling medium can be directly extracted from the evaporator 4 and / or the condenser 2. Since the evaporator 4 and the condenser 2 are large in size and contain a large amount of cooling medium, the effect of extracting a certain amount of cooling medium on the pressure of the refrigeration system is relatively small. However, if the input end of the cooling flow path is connected to the pipeline between the condenser 2 and the evaporator 4, the effect on the pressure of the refrigeration system is relatively large, so this solution is conducive to improving the reliability of the refrigeration equipment.

[0044] In some exemplary embodiments, the refrigeration system is a water refrigeration system, the compressor is a water vapor compressor, and the cooling medium is water.

[0045] Due to the special physical properties of water vapor refrigerant, it has a large specific volume, a large pressure ratio, a small pressure difference, and a high temperature after compression, which poses great difficulties in the design and operation of the entire refrigeration system. Therefore, it is necessary to perform interstage cooling between every two stages of the multi-stage compressor 1. Currently, most commonly used cooling methods use external cooling water for indirect cooling, which results in a large volume of the entire unit. For this reason, some manufacturers abandon water vapor refrigerant and use conventional refrigerants, which affects the promotion and use of water vapor refrigerant.

[0046] The refrigeration system provided in the embodiment of the present application uses a natural refrigerant, water, as a refrigerant for circulating refrigeration, and does not require an external cooling water circulation system to cool the multi-stage centrifugal compressor, which effectively solves the industry pain points of the water refrigeration system in the related technology and is conducive to the promotion and use of water vapor refrigerants.

[0047] In some exemplary embodiments, Figure 1 and Figure 2 As shown, the input end of the cooling flow path is connected to the bottom of the evaporator 4 to transport the liquid cooling medium at the bottom of the evaporator 4 to the cooler 13 .

[0048] Compared with the condenser 2, the refrigerant temperature in the evaporator 4 is lower, so using the cooling medium in the evaporator 4 to cool the refrigerant in the cooler 13 can reduce the amount of cooling medium used, which is beneficial to reducing the flow rate of the cooling flow path.

[0049] For the solution in which the multi-stage compressor 1 is a water vapor compressor, the evaporator 4 may be a flooded evaporator. During the operation of the flooded evaporator, the upper part is water vapor and the lower part is water, so the input end of the cooling flow path is connected to the bottom of the evaporator 4, and the cooling water at the bottom of the evaporator 4 can be transported to the cooler 13, which can achieve a better cooling effect and is not likely to cause changes in the evaporation pressure in the evaporator 4, thus facilitating the reliable operation of the evaporator 4.

[0050] Of course, the input end of the cooling flow path may also be connected to the bottom of the condenser 2 to transport the liquid cooling medium at the bottom of the condenser 2 to the cooler 13 .

[0051] Alternatively, the input end of the cooling flow path may also be connected to the bottom of the evaporator 4 and the bottom of the condenser 2 to transport the liquid cooling medium at the bottom of the evaporator 4 and the condenser 2 to the cooler 13 .

[0052] In some exemplary embodiments, the cooler 13 is a direct cooler 13, such as Figure 1 The direct cooler 13 is configured to allow the refrigerant discharged from the compression unit 12 into the cooler 13 to perform contact heat exchange with the cooling medium transported into the cooler 13 by the cooling flow path.

[0053] In this solution, the refrigerant discharged from the adjacent compression unit 12 on the upstream side of the cooler 13 enters the cooler 13, and the cooling medium transported by the cooling flow path also enters the cooler 13. The refrigerant discharged from the compression unit 12 directly contacts the cooling medium transported by the cooling flow path for heat exchange, and becomes a refrigerant with a temperature lower than that of the refrigerant discharged from the compression unit 12, and then is discharged from the cooler 13. The refrigerant discharged from the compression unit 12 and the cooling medium transported by the cooling flow path have the same composition, but may have different physical states, and can achieve a cooling effect through direct contact, and the amount of refrigerant output by the compression module 11 is also increased.

[0054] For example: the refrigerant discharged from the compression unit 12 is a gaseous medium, and the cooling medium transported by the cooling flow path is a liquid medium. A spray device can also be provided in the direct cooler 13, and an atomizing device can also be provided at the end of the cooling flow path. The atomizing device is connected to the spray device, and the liquid cooling medium is atomized and sprayed into the cooler 13 in the form of water mist, which is beneficial to increase the contact area between the refrigerant discharged from the compression unit 12 and the cooling medium transported by the cooling flow path, thereby improving the heat exchange effect. In addition, the atomized cooling medium can achieve a flash evaporation effect after contacting with the high-temperature and high-pressure gaseous cooling medium, and evaporates rapidly through a large amount of heat absorption, thereby reducing the superheat of the refrigerant discharged from the compression module 11.

[0055] In other exemplary embodiments, the cooler 13 is an indirect cooler 13, such as Figure 2 As shown. A first heat exchange channel and a second heat exchange channel are provided in the indirect cooler 13. The first heat exchange channel is connected to the adjacent compression unit 12. The output end of the cooling channel is connected to the input end of the second heat exchange channel. The cooling system also includes a return branch 53, the input end of the return branch 53 is connected to the output end of the second heat exchange channel, and the output end of the return branch 53 is connected to the evaporator 4 and / or the condenser 2.

[0056] The first heat exchange flow channel and the second heat exchange flow channel are configured to separate the refrigerant discharged from the compression unit 12 from the cooling medium transported by the cooling flow path, so that the refrigerant discharged from the compression unit 12 and the cooling medium transported by the cooling flow path can perform non-contact heat exchange.

[0057] In this solution, the refrigerant discharged from the compression unit 12 adjacent to the upstream side of the cooler 13 enters the first heat exchange flow channel of the cooler 13, and the cooling medium transported by the cooling flow channel enters the second heat exchange flow channel of the cooler 13. The refrigerant discharged from the compression unit 12 and the cooling medium transported by the cooling flow channel are separated from each other and cannot contact each other, and can only perform non-contact heat exchange, so that the refrigerant in the first heat exchange flow channel is discharged from the cooler 13 after the temperature is reduced; and the cooling medium in the second heat exchange flow channel absorbs heat and flows back to the evaporator 4 and / or the condenser 2 through the return branch 53. The refrigerant discharged from the compression unit 12 and the cooling medium transported by the cooling flow channel have the same composition, but may have different physical states.

[0058] The first heat exchange channel and the second heat exchange channel only separate the refrigerant discharged from the compression unit 12 from the cooling medium transported by the cooling channel, and the specific shapes of the first heat exchange channel and the second heat exchange channel are not limited. Accordingly, there are many types of indirect coolers 13, such as shell and tube heat exchangers, plate heat exchangers or other types of indirect heat exchangers.

[0059] In some embodiments, the indirect cooler 13 is a phase change cooler 13, that is, the cooling medium transported by the cooling flow path will undergo a phase change in the cooler 13. Since the latent heat of the phase change is large, the heat exchange efficiency is much higher than that of the non-phase change. Therefore, this solution is beneficial to reducing the demand for cooling medium and reducing the flow rate of the cooling flow path.

[0060] The phase change cooler 13 can be equipped with a throttling component to achieve phase change. For example, a throttling component (such as an expansion valve, a capillary tube, etc.) can be set on the cooling flow path to allow the cooling medium to enter the cooler 13 after throttling and reducing the pressure and undergo phase change.

[0061] In other embodiments, the indirect cooler 13 is a non-phase-change cooler 13, that is, the cooling medium transported by the cooling flow path does not undergo phase change in the cooler 13, and heat exchange is achieved through temperature difference. The non-phase-change cooler 13 can be equipped with a flow valve to adjust the flow to adjust the heat exchange effect.

[0062] In some exemplary embodiments, each compression module 11 includes a compression unit 12 and a cooler 13. Figure 1 and Figure 2 The cooling flow path includes a plurality of cooling branches 52 connected in parallel, and the plurality of cooling branches 52 are connected to the plurality of coolers 13 in a one-to-one correspondence.

[0063] In this way, the superheat of the refrigerant discharged from each compression module 11 can be effectively adjusted, achieving a good inter-stage cooling effect, which is beneficial to reducing the compression load of the subsequent compression module 11 and ensuring that the subsequent compression module 11 can be compressed normally, and can also make the refrigerant finally discharged from the multi-stage compressor 1 be in a suitable superheat range, so as to improve the energy efficiency of the whole machine.

[0064] In some exemplary embodiments, the cooling system further includes: a pump body 6, such as Figure 1 and Figure 2 As shown, it is connected to the cooling flow path and is configured to pump the cooling medium in the evaporator 4 and / or the condenser 2 to the cooler 13.

[0065] For the solution that the cooling flow path includes multiple cooling branches 52 connected in parallel, the number of pump bodies 6 can be one or more. For example, a pump body 6 can be provided for each cooling branch 52. Alternatively, the cooling flow path also includes a cooling main path 51 located on the upstream side of the multiple cooling branches 52, and only one pump body 6 is provided. Figure 1 and Figure 2 As shown, it is arranged on the cooling main circuit 51, which can reduce the number of pump bodies 6 and help reduce costs.

[0066] In some exemplary embodiments, the cooling system further includes: a control valve 7, such as Figure 1 and Figure 2 As shown, it is arranged in the cooling flow path and is configured to control the on-off and / or working parameters (such as flow rate, flow velocity, etc.) of the cooling flow path.

[0067] In this way, it is convenient to reasonably control the superheat of the refrigerant discharged from the cooler 13 through the control valve 7 as needed, so that the superheat of the refrigerant discharged from the cooler 13 can be within a suitable superheat range.

[0068] For the solution that the cooling flow path includes a plurality of cooling branches 52 connected in parallel, the number of control valves 7 is multiple, and the multiple control valves 7 are respectively arranged on the multiple cooling branches 52, such as Figure 1 and Figure 2 As shown, the on / off state and / or working parameters of each cooling branch 52 can be adjusted.

[0069] Furthermore, by properly setting the type of control valve 7, phase change cooling or non-phase change cooling of the indirect subcooler can also be achieved.

[0070] In some exemplary embodiments, the refrigeration device further includes: a control device (not shown in the figure), which is configured to adjust the control valve 7 according to the superheat of the refrigerant discharged from the compression unit 12 adjacent to the upstream side of the cooler 13, so that the superheat of the refrigerant discharged from the cooler 13 is within the set superheat range. In this way, automatic control of the refrigeration device can be achieved.

[0071] The superheat of the refrigerant discharged from the compression unit 12 can be determined based on the refrigerant temperature and refrigerant pressure at the outlet of the compression unit 12. The superheat of the refrigerant discharged from the cooler 13 can be determined based on the refrigerant temperature and refrigerant pressure at the outlet of the cooler 13.

[0072] like Figure 3 As shown, the embodiment of the present application further provides a control method for a refrigeration device as in any one of the above embodiments, the control method comprising:

[0073] Step S202: determining the superheat of the refrigerant discharged from the adjacent compression unit on the upstream side of the cooler;

[0074] Step S204: adjusting the on / off state and / or working parameters of the cooling flow path according to the superheat of the refrigerant discharged from the compression unit, so that the superheat of the refrigerant discharged from the cooler is within a set superheat range.

[0075] This facilitates automatic control of the superheat of the refrigerant discharged from the cooler 13, so that the superheat of the refrigerant discharged from the cooler 13 can be within a suitable superheat range to ensure the normal operation of the multi-stage compressor 1 and the normal operation of the refrigeration equipment.

[0076] In some exemplary embodiments, the cooling system further comprises: a control valve 7, which is disposed in the cooling flow path and is configured to control the on-off and / or working parameters of the cooling flow path.

[0077] The on-off and / or working parameters of the cooling flow path are adjusted according to the superheat of the refrigerant discharged from the compression unit 12, including: controlling the control valve 7 according to the superheat of the refrigerant discharged from the compression unit 12 to adjust the on-off and / or working parameters of the cooling flow path.

[0078] In this way, it is convenient to reasonably control the superheat of the refrigerant discharged from the cooler 13 through the control valve 7 as needed, so that the superheat of the refrigerant discharged from the cooler 13 can be within a suitable superheat range.

[0079] In some exemplary embodiments, each compression module 11 includes a compression unit 12 and a cooler 13. The cooling flow path includes a plurality of cooling branches 52 connected in parallel, and the plurality of cooling branches 52 are connected to the plurality of coolers 13 in a one-to-one correspondence.

[0080] Determining the superheat of the refrigerant discharged from the compression unit 12 adjacent to the upstream side of the cooler 13 includes: determining the superheat of the refrigerant discharged from the compression unit 12 adjacent to the upstream side of each cooler 13;

[0081] The on / off and / or operating parameters of the cooling flow path are adjusted according to the superheat of the refrigerant discharged from the compression unit 12, so that the superheat of the refrigerant discharged from the cooler 13 is within the set superheat range, including: according to the superheat of the refrigerant discharged from each compression unit 12, the on / off and / or operating parameters of the corresponding cooling branch 52 are adjusted, so that the superheat of the refrigerant discharged from each cooler 13 is within the set superheat range.

[0082] In this way, the superheat of the refrigerant discharged from each compression module 11 can be effectively and automatically adjusted, achieving a good inter-stage cooling effect, which is beneficial to reducing the compression load of the subsequent compression module 11 and ensuring that the subsequent compression module 11 can be compressed normally, and can also make the refrigerant finally discharged from the multi-stage compressor 1 be in a suitable superheat range, so as to improve the energy efficiency of the whole machine.

[0083] In some exemplary embodiments, the on / off and / or operating parameters of the corresponding cooling flow path are adjusted according to the superheat of the refrigerant discharged from each compression unit 12, including: adjusting the control valve 7 on the corresponding cooling branch 52 according to the superheat of the refrigerant discharged from each compression unit 12 to adjust the on / off and / or operating parameters of the corresponding cooling branch 52.

[0084] In some exemplary embodiments, the superheat range is set in the range of 2°C to 5°C.

[0085] Of course, the setting range of superheat is not limited to the above range and can be adjusted as needed.

[0086] The refrigeration device provided in the embodiment of the present application may be, but is not limited to, an air conditioner. The multi-stage compressor 1 may be a two-stage compressor or a multi-stage compressor 1. The working principle of the refrigeration device is described below by taking the refrigeration device as an air conditioner and the compressor as a two-stage compressor as an example.

[0087] like Figure 1 and Figure 2As shown, the air conditioner of this embodiment is a natural refrigerant water refrigeration air conditioning system. The refrigeration equipment mainly includes: a primary compression unit 121, a secondary compression unit 122, a primary cooler 131 (i.e., a cooler 13 located at the downstream side of the primary compression unit 121 and adjacent to the primary compression unit 121), a secondary cooler 132 (i.e., a cooler 13 located at the downstream side of the secondary compression unit 122 and adjacent to the second compression unit 12), an evaporator 4, a condenser 2, a throttling device 3, a water pump, a control valve 7, etc. The primary compression unit 121 and the primary cooler 131 constitute a primary compression module, and the secondary compression unit 122 and the secondary cooler 132 constitute a secondary compression module. The primary compression module and the secondary compression module are two compression modules 11 of a two-stage compressor, and the primary compression module is a first-stage compression module 11. The secondary compression module is located at the downstream side of the primary compression module and is a final-stage compression module 11.

[0088] The refrigeration system further includes a cooling main circuit 51, two parallel cooling branches 52, and two control valves 7 (first control valve 71 and second control valve 72) respectively arranged on the two cooling branches 52. A water pump is arranged on the cooling main circuit 51. One cooling flow path cools the cooling main circuit 51 and the cooler 13. The other cooling flow path connects the cooling main circuit 51 and the secondary cooler 132.

[0089] The evaporator 4 is a full-liquid evaporator, which mainly evaporates liquid water, absorbs the heat of the room, and achieves the effect of cooling the room. The evaporator 4 evaporates and absorbs part of the heat of the water. The evaporated water vapor flows into the two-stage centrifugal compressor through the outlet of the evaporator 4. The two-stage centrifugal compressor mainly compresses the water vapor generated by the evaporator 4, and increases the pressure of the water vapor to the pressure required for work. The primary cooler 131 and the secondary cooler 132 cool down the superheated water vapor compressed by the primary compression unit 121 and the secondary compression unit 122, respectively, and keep the superheat between 2°C and 5°C. The condenser 2 mainly condenses the water vapor discharged from the two-stage compressor, exchanges the heat of the water vapor to the outside, condenses it into supercooled water, and flows out of the condenser 2. The throttling device 3 mainly depressurizes and throttles the supercooled water generated by the condenser 2, reduces the pressure to the pressure condition of the evaporation temperature, and makes it flow into the evaporator 4 for evaporation, reaches the expected evaporation temperature, and achieves the expected refrigeration effect.

[0090] The primary cooler 131 and the secondary cooler 132 cool the water vapor compressed by the primary compression unit 121 and the secondary compression unit 122 mainly by introducing cold water from the bottom of the evaporator 4. The cooler 13 can have two embodiments.

[0091] like Figure 1As shown, the first embodiment is direct contact cooling, that is, the cooler 13 is a direct cooler 13, which uses cold water to reduce pressure and flash evaporation to mix with superheated water vapor to achieve the purpose of reducing superheat. The principle is to pressurize the cold water through a water pump to form cold water of a certain pressure, and then convert the high-pressure cold water into water mist through the control valve 7 and the atomizing device and spray it into the cooler 13. The water mist absorbs heat and evaporates, absorbing a large amount of heat from the water vapor, reducing the superheat of the water vapor, and controlling the superheat at 2°C to 5°C. After that, it enters the secondary compression unit 122, and the pressure of the water vapor is increased again. Using the same method, the superheat of the compressed water vapor is reduced again. The cooling water is supplemented by the evaporator 4. In the whole system, the cooling water circulates and cools, and reaches dynamic balance with the whole system.

[0092] like Figure 2 As shown, the second embodiment is indirect cooling, that is, the cooler 13 is an indirect cooler 13. Indirect cooling can also be divided into two types, one is water vapor evaporation indirect cooling (that is, phase change cooling), and the other is non-evaporation indirect cooling (that is, non-phase change cooling). Cold water is drawn from the bottom of the evaporator 4, the flow rate is adjusted by a water pump and a control valve 7, and the water vapor is cooled by a shell and tube heat exchanger, a plate heat exchanger or other types of indirect heat exchangers to reduce the superheat of the water vapor to 2°C to 5°C. If it is evaporative indirect cooling, the control valve 7 can be an expansion valve. At this time, due to the large latent heat of evaporation of water, the flow rate can be small. If it is non-evaporative indirect cooling, the control valve 7 can be a flow valve, and the flow rate is large at this time. The flow rate is dynamically adjusted according to the superheat of the two compression units 12 until it reaches the preset superheat range.

[0093] The condenser 2 is mainly used to condense the water vapor at the outlet of the two-stage compression unit 12 after inter-stage cooling, and a subcooling section is also provided at the tail of the condenser 2 to further cool the saturated liquid into subcooled water. Its form is not limited, and it can be a fin-tube condenser 2, a spray condenser 2, a shell-and-tube condenser 2, etc.

[0094] The throttling device 3 is mainly used to reduce the pressure of the high-pressure supercooled water at the outlet of the condenser 2. Since the water refrigeration system operates in a negative pressure environment, the pressure difference is very small, so the form of the throttling device 3 is not limited to an expansion valve, a hole baffle, a liquid level column, a capillary tube, etc.

[0095] like Figure 1 and Figure 2As shown, when the whole system is running, the full liquid evaporator 4 evaporates, part of which absorbs the heat in the room, and part of which absorbs the heat of the remaining water. At this time, it shows a state of upper gas and lower liquid. The water vapor flows out from the upper outlet of the evaporator 4. At this time, the refrigerant pressure and temperature are P1 and T1, and T1 should have a certain degree of superheat. Then the water vapor flows into the primary compression unit 121, and the water vapor is compressed by the primary compression unit 121. After compression, it is discharged from the primary compression unit 121. At this time, the pressure and temperature of the water vapor rise to P2 and T2. At this time, the superheat of the water vapor is high. In order to ensure the normal compression later, it needs to be cooled. At this time, the cold water introduced into the bottom of the evaporator 4 is reduced by the water pump and the control valve 7 in the direct spray flash form of the first embodiment or the indirect cooling form of the second embodiment to reduce its superheat to within the preset range. The preset range can be 2°C to 5°C. At this time, the pressure and temperature of the water vapor are P2 and T3 (T3<T2). After being reduced, it flows into the secondary compression unit 122. After passing through the secondary compression unit 122, the pressure and temperature continue to rise to P3 and T4. At this time, the pressure reaches the target design pressure, and the temperature superheat is relatively large. The same form is adopted to introduce cold water at the bottom of the evaporator 4. Through the water pump and the control valve 7, the direct spray flash form of the first embodiment or the indirect cooling form of the second embodiment is adopted to reduce its superheat, and the superheat is reduced to within the preset range. The preset range can be 2°C to 5°C. At this time, the pressure and temperature of the water vapor are P3 and T5 (T5<T4). After that, it flows into the condenser 2 to condense into liquid water, and then the liquid water is further supercooled into supercooled water (pressure and temperature are T6 and P6). The supercooled water flows into the evaporator 4 after the throttling device 3 reduces the pressure and throttles, evaporates in the evaporator 4, and continues to flow into the multi-stage compressor 1 after evaporation, thereby completing the refrigeration cycle.

[0096] The refrigeration equipment using the cooler 13 of the first embodiment has a working principle as follows: Figure 4 The cooling device of the second embodiment adopts the cooling air, and its working principle is as follows Figure 5 shown.

[0097] Therefore, the refrigeration equipment and control method provided by the embodiment of the present application, the interstage cooling scheme of the multi-stage compressor adopts a system closed cooling scheme, does not require an external cooling source, and the cooling water uses the cold water at the bottom of the system evaporator. Through direct contact spray flash cooling or indirect evaporative cooling or indirect non-evaporative cooling and other methods, the superheat of the water vapor after compression of the first compression unit and the second compression unit can be reduced. The system has good integrity, stable operation, high efficiency, and good cooling effect. This interstage cooling scheme can reduce the size and cost of the overall unit and improve the overall efficiency of the system.

[0098] An embodiment of the present application also provides a control device, including a processor and a memory storing a computer program. When the processor executes the computer program, the steps of the control method of the above embodiment are implemented, and thus all the above-mentioned beneficial effects are achieved, which will not be repeated here.

[0099] The processor may be an integrated circuit chip with signal processing capabilities. The above-mentioned processor may be a general-purpose processor, including a central processing unit (CPU), a network processor (NP), etc.; it may also be a digital signal processor (DSP), an application-specific integrated circuit (ASIC), a field-programmable gate array (FPGA) or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components. The methods, steps and logic block diagrams disclosed in the embodiments of the present invention may be implemented or executed. The general-purpose processor may be a microprocessor or the processor may also be any conventional processor, etc.

[0100] The embodiment of the present application also provides a computer-readable storage medium, including a computer program. When the computer program is executed by a processor, the steps of the control method of the above embodiment are implemented, and thus all the above-mentioned beneficial effects are achieved, which will not be repeated here.

[0101] In the description of the present application, 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 application 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 application.

[0102] 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 this application, the meaning of "plurality" is at least two, such as two, three, etc., unless otherwise clearly and specifically defined.

[0103] In this application, 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 connection; it can be a mechanical connection or an electrical connection; 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 this application can be understood according to specific circumstances.

[0104] In the present application, 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”, and “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”, and “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.

[0105] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" etc. means 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 application. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described 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.

[0106] Although the embodiments of the present application have been shown and described above, it can be understood that the above embodiments are exemplary and cannot be understood as limitations on the present application. Ordinary technicians in this field can change, modify, replace and modify the above embodiments within the scope of the present application.

[0107] In any one or more of the above exemplary embodiments, the functions described may be implemented in hardware, software, firmware, or any combination thereof. If implemented in software, the functions may be stored on a computer-readable medium or transmitted via a computer-readable medium as one or more instructions or codes, and executed by a hardware-based processing unit. A computer-readable medium may include a computer-readable storage medium corresponding to a tangible medium such as a data storage medium, or a communication medium that facilitates a computer program, such as any medium transmitted from one place to another according to a communication protocol. In this way, a computer-readable medium may generally correspond to a non-temporary tangible computer-readable storage medium or a communication medium such as a signal or carrier wave. A data storage medium may be any available medium that can be accessed by one or more computers or one or more processors to retrieve instructions, codes, and / or data structures for implementing the technology described in the present disclosure. A computer program product may include a computer-readable medium.

[0108] By way of example and not limitation, such computer-readable storage media may include RAM, ROM, EEPROM, CD-ROM or other optical disk storage, magnetic disk storage or other magnetic storage, flash memory, or any other medium that can be used to store the desired program code in the form of instructions or data structures and can be accessed by a computer. Moreover, any connection may also be referred to as a computer-readable medium. For example, if instructions are transmitted from a website, server or other remote source using coaxial cable, fiber optic cable, twisted pair, digital subscriber line (DSL), or wireless technologies such as infrared, radio and microwave, then coaxial cable, fiber optic cable, twisted pair, DSL, or wireless technologies such as infrared, radio and microwave are included in the definition of medium. However, it should be understood that computer-readable storage media and data storage media do not include connections, carrier waves, signals, or other transient (transient) media, but are directed to non-transient tangible storage media. As used herein, disks and optical disks include compact disks (CDs), laser disks, optical disks, digital versatile disks (DVDs), floppy disks, or Blu-ray disks, etc., where disks typically reproduce data magnetically, while optical disks use lasers to reproduce data optically. Combinations of the above should also be included within the scope of computer-readable media.

[0109] For example, instructions may be executed by one or more processors such as one or more digital signal processors (DSPs), general purpose microprocessors, application specific integrated circuits (ASICs), field programmable logic arrays (FPGAs), or other equivalent integrated or discrete logic circuits. Thus, the term "processor" as used herein may refer to any of the above structures or any other structures suitable for implementing the techniques described herein. Additionally, in some aspects, the functionality described herein may be provided within dedicated hardware and / or software modules configured for encoding and decoding, or incorporated in a combined codec. Also, the techniques may be fully implemented in one or more circuits or logic elements.

[0110] The technical solutions of the embodiments of the present disclosure can be implemented in a wide variety of devices or equipment, including wireless mobile phones, integrated circuits (ICs) or a group of ICs (e.g., chipsets). Various components, modules or units are described in the embodiments of the present disclosure to emphasize the functional aspects of the devices configured to perform the described techniques, but they do not necessarily need to be implemented by different hardware units. Instead, as described above, the various units can be combined in a codec hardware unit or provided by a collection of interoperable hardware units (including one or more processors as described above) in combination with suitable software and / or firmware.

Claims

1. A refrigeration device, characterized in that: include: A refrigeration system, comprising a multi-stage compressor, a condenser, a throttling device and an evaporator connected in sequence end to end, wherein the multi-stage compressor comprises a plurality of compression modules connected in sequence, at least one of the compression modules comprises a compression unit and a cooler, the cooler is located at the downstream side of the compression unit and communicated with the compression unit, and each of the compression modules comprises the compression unit; and The cooling system comprises a cooling flow path, wherein the input end of the cooling flow path is connected to the evaporator and / or the condenser, and the output end of the cooling flow path is connected to the cooler, and is configured to transport the cooling medium in the evaporator and / or the condenser to the cooler to reduce the superheat of the refrigerant discharged from the cooler.

2. The refrigeration equipment according to claim 1, characterized in that: The cooler is a direct cooler, and the direct cooler is configured to allow the refrigerant discharged from the compression unit to perform contact heat exchange with the cooling medium transported by the cooling flow path.

3. The refrigeration equipment according to claim 1, characterized in that: The cooler is an indirect cooler, and a first heat exchange channel and a second heat exchange channel are provided in the indirect cooler, the first heat exchange channel is connected to the adjacent compression unit, and the output end of the cooling channel is connected to the input end of the second heat exchange channel; the cooling system also includes a return branch, the input end of the return branch is connected to the output end of the second heat exchange channel, and the output end of the return branch is connected to the evaporator and / or the condenser; the first heat exchange channel and the second heat exchange channel are configured to separate the refrigerant discharged from the compression unit from the cooling medium transported by the cooling channel, so that the refrigerant discharged from the compression unit and the cooling medium transported by the cooling channel can perform non-contact heat exchange.

4. The refrigeration equipment according to claim 3, characterized in that: The indirect cooler is a phase change cooler; or, the indirect cooler is a non-phase change cooler.

5. The refrigeration device according to any one of claims 1 to 4, characterized in that: The input end of the cooling flow path is connected to the bottom of the evaporator to transport the liquid cooling medium at the bottom of the evaporator to the cooler.

6. The refrigeration device according to any one of claims 1 to 4, characterized in that: Each of the compression modules includes the compression unit and the cooler, and the cooling flow path includes a plurality of cooling branches connected in parallel, and the plurality of cooling branches are connected to the plurality of coolers in a one-to-one correspondence.

7. The refrigeration device according to any one of claims 1 to 4, characterized in that: The cooling system further comprises: The control valve is arranged in the cooling flow path and is configured to control the on-off and / or working parameters of the cooling flow path.

8. The refrigeration device according to claim 7, characterized in that: Also includes: The control device is configured to adjust the control valve according to the superheat of the refrigerant discharged from the compression unit adjacent to the upstream side of the cooler, so that the superheat of the refrigerant discharged from the cooler is within a set superheat range.

9. The refrigeration device according to any one of claims 1 to 4, characterized in that: The cooling system further comprises: The pump body is communicated with the cooling flow path and is configured to pump the cooling medium in the evaporator and / or the condenser to the cooler.

10. The refrigeration device according to any one of claims 1 to 4, characterized in that: The refrigeration system is a water refrigeration system, the compressor is a water vapor compressor, and the cooling medium is water; and / or The refrigeration equipment is an air conditioner.

11. A control method, characterized in that: For a refrigeration device as claimed in any one of claims 1 to 10, the control method comprises: determining the superheat of the refrigerant discharged from the compression unit adjacent to the upstream side of the cooler; The on / off state and / or working parameters of the cooling flow path are adjusted according to the superheat of the refrigerant discharged from the compression unit, so that the superheat of the refrigerant discharged from the cooler is within a set superheat range.

12. The control method according to claim 11, characterized in that: Each of the compression modules comprises the compression unit and the cooler, the cooling flow path comprises a plurality of cooling branches connected in parallel, and the plurality of cooling branches are connected to the plurality of coolers in a one-to-one correspondence; Determining the superheat of the refrigerant discharged from the compression unit adjacent to the upstream side of the cooler comprises: determining the superheat of the refrigerant discharged from the compression unit adjacent to each of the coolers on the upstream side; The on-off and / or working parameters of the cooling flow circuit are adjusted according to the superheat of the refrigerant discharged by the compression unit so that the superheat of the refrigerant discharged by the cooler is within a set superheat range, including: according to the superheat of the refrigerant discharged by each of the compression units, the on-off and / or working parameters of the corresponding cooling branch are adjusted so that the superheat of the refrigerant discharged by each of the coolers is within a set superheat range.

13. A control device, characterized in that: The system comprises a processor and a memory storing a computer program, wherein when the processor executes the computer program, the steps of the control method according to claim 11 or 12 are implemented.

14. A computer-readable storage medium comprising a computer program, characterized in that: When the computer program is executed by a processor, the steps of the control method according to claim 11 or 12 are implemented.

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