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CN117847813A - Refrigerant circulation system, control method thereof and refrigeration equipment - Google Patents

Refrigerant circulation system, control method thereof and refrigeration equipment Download PDF

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Publication number
CN117847813A
CN117847813A CN202311792564.9A CN202311792564A CN117847813A CN 117847813 A CN117847813 A CN 117847813A CN 202311792564 A CN202311792564 A CN 202311792564A CN 117847813 A CN117847813 A CN 117847813A
Authority
CN
China
Prior art keywords
refrigerant
electromagnetic valve
flow path
air supply
gaseous refrigerant
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Pending
Application number
CN202311792564.9A
Other languages
Chinese (zh)
Inventor
梁湖
梁海英
周宇
黄成武
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Gree Electric Appliances Inc of Zhuhai
Original Assignee
Gree Electric Appliances Inc of Zhuhai
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Gree Electric Appliances Inc of Zhuhai filed Critical Gree Electric Appliances Inc of Zhuhai
Priority to CN202311792564.9A priority Critical patent/CN117847813A/en
Publication of CN117847813A publication Critical patent/CN117847813A/en
Pending legal-status Critical Current

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Classifications

    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
    • F25B—REFRIGERATION MACHINES, PLANTS OR SYSTEMS; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS
    • F25B1/00—Compression machines, plants or systems with non-reversible cycle
    • F25B1/005—Compression machines, plants or systems with non-reversible cycle of the single unit type
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
    • F25B—REFRIGERATION MACHINES, PLANTS OR SYSTEMS; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS
    • F25B41/00—Fluid-circulation arrangements
    • F25B41/20—Disposition of valves, e.g. of on-off valves or flow control valves
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
    • F25B—REFRIGERATION MACHINES, PLANTS OR SYSTEMS; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS
    • F25B41/00—Fluid-circulation arrangements
    • F25B41/30—Expansion means; Dispositions thereof
    • F25B41/31—Expansion valves
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
    • F25B—REFRIGERATION MACHINES, PLANTS OR SYSTEMS; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS
    • F25B41/00—Fluid-circulation arrangements
    • F25B41/40—Fluid line arrangements
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
    • F25B—REFRIGERATION MACHINES, PLANTS OR SYSTEMS; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS
    • F25B49/00—Arrangement or mounting of control or safety devices
    • F25B49/02—Arrangement or mounting of control or safety devices for compression type machines, plants or systems

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  • Engineering & Computer Science (AREA)
  • Physics & Mathematics (AREA)
  • Mechanical Engineering (AREA)
  • Thermal Sciences (AREA)
  • General Engineering & Computer Science (AREA)
  • Air Conditioning Control Device (AREA)

Abstract

The application relates to a refrigerant circulation system and a control method thereof, and refrigeration equipment, wherein the refrigerant circulation system comprises a compressor with a gas suspension bearing, a condenser for condensing a refrigerant compressed by the compressor, an evaporator for evaporating the refrigerant condensed in the condenser and a gas supply system for conveying the gaseous refrigerant to the gas suspension bearing, and the gas supply system comprises a gaseous refrigerant main flow path, a gas supply tank, a first one-way valve, a gas supply pump, a first electromagnetic valve, a gaseous refrigerant branch flow path, a second electromagnetic valve, a third electromagnetic valve and a controller. The controller is in signal connection with the first electromagnetic valve, the second electromagnetic valve and the third electromagnetic valve respectively, so that the second electromagnetic valve is opened after the air supply pump is stopped by fault, the third electromagnetic valve is closed, and the bearing can be always supplied with air when the static pressure air suspension compressor is stopped normally, stopped by fault, abnormally powered off or the air supply pump is stopped by fault, so that reliable and stable operation of the unit is ensured.

Description

Refrigerant circulation system, control method thereof and refrigeration equipment
Technical Field
The application relates to the technical field of refrigeration, in particular to a refrigerant circulating system, a control method thereof and refrigeration equipment.
Background
The centrifugal water chiller is widely applied to industrial, commercial, residential and other building groups at present, and the reliability of the centrifugal water chiller is widely accepted in the market. In general, a compressor of a centrifugal water chilling unit adopts an oil lubrication bearing, a magnetic suspension bearing and an air suspension bearing, and the air suspension bearing which is just emerging in the refrigeration industry is divided into a dynamic pressure air suspension bearing and a static pressure air suspension bearing, wherein the dynamic pressure air suspension bearing and the static pressure air suspension bearing are mature and are put into the market in large quantities compared with the dynamic pressure air suspension bearing and the static pressure air suspension bearing, so the dynamic pressure air suspension bearing is also a competitive focus in the industry.
In the existing refrigerant pump and electric heating air supply scheme, when a unit is stopped due to the failure of the refrigerant pump, the condenser is subjected to quick pressure relief, and air is supplied only by a bearing when the rest air of the air storage tank is stopped, so that the risk of insufficient air supply possibly exists; and the condenser is not provided with the pressure relief device, can not continue to provide high-pressure gaseous refrigerant, and the risk of serious abrasion of the bearing possibly exists, so that the reliability and the precision of the bearing are influenced, and the working reliability of the unit is influenced.
Disclosure of Invention
The application provides a refrigerant circulation system, a control method thereof and refrigeration equipment, which are used for solving the technical problems that when a refrigerant pump fault causes a machine set to stop, a condenser rapidly decompresses to cause insufficient air supply and influence the working reliability of the machine set.
In a first aspect, the present application provides a refrigerant circulation system, including a compressor having a gas suspension bearing, a condenser for condensing refrigerant compressed by the compressor, an evaporator for evaporating refrigerant condensed in the condenser, and a gas supply system for delivering gaseous refrigerant to the gas suspension bearing, the gas supply system comprising: the gaseous refrigerant main flow path comprises an inlet end which is communicated with the condenser to introduce the gaseous refrigerant and an outlet end for outputting the gaseous refrigerant; the gas supply tank comprises a gas inlet communicated with the outlet end of the gaseous refrigerant main flow path and a gas outlet for supplying gaseous refrigerant to the gas suspension bearing; the first one-way valve is arranged in the main flow path of the gaseous refrigerant, the inlet end of the first one-way valve is communicated with the condenser, and the outlet end of the first one-way valve is communicated with the air supply tank; the air supply pump is arranged in the gaseous refrigerant main flow path so as to convey the gaseous refrigerant in the condenser to the air supply tank; the first electromagnetic valve is arranged in the gaseous refrigerant main flow path and is provided with an inlet end communicated with an air inlet of the gaseous refrigerant main flow path and an outlet end communicated with the air supply pump; the gaseous refrigerant branch flow path comprises an inlet end communicated with the inlet end of the first electromagnetic valve and an outlet end communicated with the outlet end of the first one-way valve; the second electromagnetic valve is arranged in the gaseous refrigerant branch flow path; the third electromagnetic valve is arranged in a pipeline between the condenser and the evaporator to control the on-off of the condenser and the evaporator; and the controller is in signal connection with the first electromagnetic valve, the second electromagnetic valve and the third electromagnetic valve respectively so as to open the second electromagnetic valve and close the third electromagnetic valve after the air supply pump is stopped due to failure.
In one possible embodiment, the air supply system further comprises: a first pressure detection unit provided in the gas supply tank for detecting the pressure of the gaseous refrigerant in the gas supply tank; the second pressure detection component is arranged on the compressor and is used for detecting the pressure of the gaseous refrigerant in the compressor; the controller is connected with the air supply tank pressure detection component and the compressor pressure detection component in a signal mode respectively so as to start the compressor after the difference value between the pressure of the refrigerant in the air supply tank and the pressure of the refrigerant in the compressor is larger than or equal to a preset pressure threshold value.
In one possible embodiment, the air supply system further includes a third pressure detecting part provided on the condenser for detecting a pressure of the refrigerant in the condenser; the controller is connected with the condenser pressure detection component in a signal way, and after the compressor operates normally, the air supply mode is switched according to the difference value between the pressure of the refrigerant in the condenser and the pressure of the gaseous refrigerant in the compressor.
In one possible embodiment, the air supply system further comprises: the liquid refrigerant main flow path comprises an inlet end for introducing liquid refrigerant condensed by the condenser and an outlet end for outputting the liquid refrigerant; the fourth electromagnetic valve is arranged on the liquid refrigerant main flow path to control the on-off of the liquid refrigerant main flow path; the cooling plate exchanger is provided with an air inlet communicated with the outlet end of the gaseous refrigerant main flow path and the outlet end of the gaseous refrigerant branch flow path, and an air outlet communicated with the air inlet of the air supply tank; the liquid inlet of the cooling plate exchanger is communicated with the outlet end of the liquid refrigerant main flow path, and the liquid outlet of the cooling plate exchanger is communicated with the evaporator.
In one possible embodiment, the gas supply system further includes a first temperature detecting member provided in the gas supply tank for detecting a gas supply temperature; the controller is respectively in signal connection with the first temperature detection component and the fourth electromagnetic valve so as to control the fourth electromagnetic valve to be opened when the air supply temperature is greater than a first temperature threshold value.
In one possible embodiment, the air supply system further comprises a cooling electronic expansion valve disposed in the liquid refrigerant main flow path, and the controller is in signal connection with the cooling electronic expansion valve to adjust the opening of the cooling electronic expansion valve when the air supply temperature is less than a second temperature threshold, the second temperature threshold being less than the first temperature threshold.
In one possible embodiment, the air supply system further comprises: the liquid refrigerant branch flow path comprises an inlet end and an outlet end which are respectively communicated with an inlet and an outlet of the cooling electronic expansion valve; a throttling element arranged on the liquid refrigerant branch flow path; a fifth electromagnetic valve arranged on the liquid refrigerant branch flow path; the controller is in signal connection with the fifth electromagnetic valve so as to control the opening of the fifth electromagnetic valve when the cooling electronic expansion valve is opened to the maximum opening and the air supply temperature is still greater than the first temperature threshold value.
In one possible embodiment, the compressor further comprises a second one-way valve arranged in a pipeline between the compressor and the condenser, an inlet end of the second one-way valve is communicated with an exhaust port of the compressor, and an outlet end of the second one-way valve is communicated with the condenser.
In one possible embodiment, the refrigerant circulation system further includes a first filter provided in the gaseous refrigerant branch flow path, a second filter provided in the gaseous refrigerant main flow path, and a third filter provided in the flow path between the gas supply tank and the gas suspension bearing of the compressor.
In a second aspect, the present application further provides a control method of the refrigerant circulation system as described above, including: acquiring a stop signal of a refrigerant circulation system; if the stop signal is that the air supply pump is in fault stop, the second electromagnetic valve is opened, and the third electromagnetic valve is closed, so that the gaseous refrigerant is continuously supplied to the air suspension bearing; if the shutdown signal is a system normal shutdown or other fault shutdown, the second electromagnetic valve and the third electromagnetic valve are closed, and the air supply pump and the first electromagnetic valve are controlled to be closed after a preset time so as to provide the gaseous refrigerant for the air suspension bearing before the compressor completely stops rotating.
In one possible implementation manner, the air supply system further comprises a liquid refrigerant main flow path, a fourth electromagnetic valve arranged in the liquid refrigerant main flow path, a cooling plate exchanger and a first temperature detection component arranged in the air supply tank, wherein an air inlet of the cooling plate exchanger is communicated with an outlet end of the gaseous refrigerant main flow path and an outlet end of the gaseous refrigerant branch flow path, and an air outlet of the cooling plate exchanger is communicated with an air inlet of the air supply tank; the inlet of the cooling plate exchanger is communicated with the outlet end of the liquid refrigerant main flow path, the outlet of the cooling plate exchanger is communicated with the evaporator, and the control method further comprises the following steps: acquiring the air supply temperature; and if the air supply temperature is greater than the first temperature threshold value, opening the fourth electromagnetic valve.
In one possible embodiment, the air supply system further includes a cooling electronic expansion valve disposed in the main flow path of the liquid refrigerant, and the control method further includes: if the air supply temperature is greater than the first temperature threshold value, opening a fourth electromagnetic valve, and gradually increasing the opening of the cooling electronic expansion valve until the opening is maximum; if the air supply temperature is smaller than a second temperature threshold value, gradually reducing the opening of the cooling electronic expansion valve, wherein the second temperature threshold value is smaller than the first temperature threshold value; if the supply air temperature is between the second temperature threshold value and the first temperature threshold value, the opening degree of the cooling electronic expansion valve is kept unchanged.
In a third aspect, the present application also provides a refrigeration apparatus, comprising: a refrigerant circulation system as described above.
Compared with the prior art, the technical scheme provided by the embodiment of the application has the following advantages:
according to the refrigerant circulation system, the control method thereof and the refrigeration equipment, when the system is stopped due to the fault of the air supply pump, the second electromagnetic valve is opened, the third electromagnetic valve is closed, so that the condenser high-pressure gaseous refrigerant is kept in a state before the stop to the greatest extent, the pressure release of the condenser is prevented or slowed down, the only flow direction of the condenser high-pressure gaseous refrigerant is the air inlet of the air supply tank, the residual gaseous refrigerant of the air supply tank is used for continuously supplying air, and meanwhile, the condenser high-pressure gaseous refrigerant participates in the air supply through the gaseous refrigerant branch flow path, so that the high-pressure gaseous refrigerant is beneficial to providing the high-pressure gaseous refrigerant for the air suspension bearing after the stop of the compressor and before the complete stop of the movement, the air suspension bearing is prevented from being seriously worn due to insufficient air supply, the reliability and the precision of the air suspension bearing are guaranteed, and the reliable and stable operation of a unit is guaranteed.
Drawings
The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments consistent with the application and together with the description, serve to explain the principles of the application.
In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings that are required to be used in the description of the embodiments or the prior art will be briefly described below, and it will be obvious to those skilled in the art that other drawings can be obtained from these drawings without inventive effort.
One or more embodiments are illustrated by way of example and not limitation in the figures of the accompanying drawings, in which like references indicate similar elements, and in which the figures of the drawings are not to be taken in a limiting sense, unless otherwise indicated.
Fig. 1 is a schematic structural diagram of a refrigerant circulation system according to an embodiment of the present disclosure;
fig. 2 is a flowchart of a control method of a refrigerant circulation system according to an embodiment of the present application.
Reference numerals illustrate:
1. a compressor; 2. a condenser; 3. an evaporator; 4. a main flow path of a gaseous refrigerant; 5. a gas supply tank; 6. a first one-way valve; 7. an air supply pump; 8. a first electromagnetic valve; 9. a gaseous refrigerant branch passage; 10. a second electromagnetic valve; 11. a third electromagnetic valve; 12. a first pressure detecting member; 13. a second pressure detecting part; 14. a third pressure detecting section; 15. a liquid refrigerant main flow path; 16. a fourth electromagnetic valve; 17. exchanging a cooling plate; 18. a first temperature detecting part; 19. cooling the electronic expansion valve; 20. a liquid refrigerant branch passage; 21. a throttle element; 22. a fifth electromagnetic valve; 23. a second one-way valve; 24. a first filter; 25. a second filter; 26. a third filter; 27. a throttle electronic expansion valve.
Detailed Description
For the purposes of making the objects, technical solutions and advantages of the embodiments of the present application more clear, the technical solutions of the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application, and it is apparent that the described embodiments are some embodiments of the present application, but not all embodiments. All other embodiments, which can be made by one of ordinary skill in the art without undue burden from the present disclosure, are within the scope of the present application based on the embodiments herein.
The following disclosure provides many different embodiments, or examples, for implementing different structures of the application. In order to simplify the disclosure of the present application, the components and arrangements of specific examples are described below. Of course, they are merely examples and are not intended to limit the present application. Furthermore, the present application may repeat reference numerals and/or letters in the various examples. This repetition is for the purpose of simplicity and clarity and does not in itself dictate a relationship between the various embodiments and/or configurations discussed.
For ease of description, spatially relative terms, such as "inner," "outer," "lower," "upper," "above," "front," "rear," and the like, may be used herein to describe one element's or feature's relative positional relationship or movement to another element's or feature as illustrated in the figures. Such spatially relative terms are intended to encompass different orientations of the device in use or operation in addition to the orientation depicted in the figures. For example, if the device in the figure experiences a position flip or a change in attitude or a change in state of motion, then the indications of these directivities correspondingly change, for example: an element described as "under" or "beneath" another element or feature would then be oriented "over" or "above" the other element or feature. Thus, the example term "below … …" may include both upper and lower orientations. The device may be otherwise oriented (rotated 90 degrees or in other directions) and the spatial relative relationship descriptors used herein interpreted accordingly.
In order to solve the technical problems that in the prior art, when a refrigerant pump fault causes a machine set to stop, a condenser rapidly decompresses to cause insufficient air supply and influences the working reliability of the machine set, the application provides a refrigerant circulating system, a control method thereof and refrigeration equipment, and the technical problems can be solved that when a static pressure air suspension compressor is stopped normally, stopped by fault, abnormally powered off or the air supply pump is stopped by fault, a bearing always supplies air, so that the reliable and stable operation of the machine set is ensured.
Fig. 1 is a refrigerant circulation system provided in an embodiment of the present application, including a compressor 1 having a gas suspension bearing, a condenser 2 for condensing a refrigerant compressed by the compressor 1, an evaporator 3 for evaporating the refrigerant condensed in the condenser 2, and a gas supply system for delivering a gaseous refrigerant to the gas suspension bearing, where the gas supply system includes a gaseous refrigerant main flow path 4, a gas supply tank 5, a first check valve 6, a gas supply pump 7, a first solenoid valve 8, a gaseous refrigerant branch flow path 9, a second solenoid valve 10, a third solenoid valve 11, and a controller.
The gaseous refrigerant main flow path 4 comprises an inlet end communicated with the condenser 2 for introducing the gaseous refrigerant and an outlet end for outputting the gaseous refrigerant; the gas supply tank 5 comprises a gas inlet communicated with the outlet end of the gaseous refrigerant main flow path 4 and a gas outlet for supplying gaseous refrigerant to the gas suspension bearing; the first one-way valve 6 is arranged in the main flow path 4 of the gaseous refrigerant, the inlet end of the first one-way valve 6 is communicated with the condenser 2, and the outlet end of the first one-way valve 6 is communicated with the air supply tank 5; the air supply pump 7 is arranged in the gaseous refrigerant main flow path 4 to convey the gaseous refrigerant in the condenser 2 to the air supply tank 5; a first electromagnetic valve 8 is provided in the gaseous refrigerant main flow path 4, the first electromagnetic valve 8 having an inlet end communicating with an intake port of the gaseous refrigerant main flow path 4 and an outlet end communicating with the air supply pump 7; the gaseous refrigerant branch flow path 9 comprises an inlet end communicated with the inlet end of the first electromagnetic valve 8 and an outlet end communicated with the outlet end of the first one-way valve 6; the second electromagnetic valve 10 is arranged in the gaseous refrigerant branch flow path 9, and bypasses the gaseous refrigerant main flow path 4 according to the opening and closing of the second electromagnetic valve 10; the third electromagnetic valve 11 is arranged in a pipeline between the condenser 2 and the evaporator 3 to control the on-off of the condenser 2 and the evaporator 3; the controller is in signal connection with the first solenoid valve 8, the second solenoid valve 10 and the third solenoid valve 11, respectively, to open the second solenoid valve 10 and close the third solenoid valve 11 after a failure of the air supply pump 7 has been stopped.
When the system works normally, the second electromagnetic valve 10 is closed, the first electromagnetic valve 8 and the third electromagnetic valve 11 are opened, the air supply pump 7 is opened, and the air supply tank 5 continuously supplies high-pressure gaseous refrigerant to the air suspension bearing so as to ensure the normal operation of the compressor 1; when the system is shut down due to the failure of the air supply pump 7, the second electromagnetic valve 10 is opened, the third electromagnetic valve 11 is closed, so that the high-pressure gaseous refrigerant of the condenser 2 keeps the state before the shut down to the greatest extent, the pressure relief of the condenser 2 is prevented or slowed down, the only flow direction of the high-pressure gaseous refrigerant of the condenser 2 is the air inlet of the air supply tank 5, the residual gaseous refrigerant of the air supply tank 5 is continuously supplied, and meanwhile, the high-pressure gaseous refrigerant of the condenser 2 participates in the air supply through the gaseous refrigerant branch flow path 9, thereby being beneficial to providing the high-pressure gaseous refrigerant for the air suspension bearing after the shut down of the compressor 1 and before the complete stop of the movement, avoiding the serious abrasion of the air suspension bearing due to insufficient air supply, and further ensuring the reliability and the precision of the air suspension bearing, and further ensuring the reliable and stable operation of the unit. Of course, when the system is shut down due to the failure of the air supply pump 7, the first electromagnetic valve 8 may be opened to allow the high-pressure gaseous refrigerant of the condenser 2 to participate in the air supply from the gaseous refrigerant main flow path 4 and the gaseous refrigerant sub-flow path 9, respectively, and because the air supply pump 7 is shut down due to the failure, the resistance is large, and therefore, more gaseous refrigerant participates in the air supply from the gaseous refrigerant sub-flow path 9.
In some embodiments, the aero-suspension bearing comprises a hydrostatic aero-suspension bearing.
In some embodiments, the controller is in signal communication with the gas supply pump 7 and is configured to control the gas supply pump 7 and the first solenoid valve 8 to close after a predetermined time of the compressor 1 shutdown to provide gaseous refrigerant to the gas suspension bearings before the compressor 1 completely stops rotating.
When the system is stopped normally or in other faults, the second electromagnetic valve 10 and the third electromagnetic valve 11 are closed, the air supply pump 7 and the first electromagnetic valve 8 are closed in a delayed mode, and the main flow path 4 of the gaseous refrigerant is always in a normal air supply state before the compressor 1 is completely stopped, so that the refrigerant in the condenser 2 is conveyed to the air supply tank 5 and the air suspension bearing more.
In some embodiments, the gas supply system further includes a first pressure detecting part 12 and a second pressure detecting part 13, the first pressure detecting part 12 being provided on the gas supply tank 5 for detecting the pressure P1 of the gaseous refrigerant in the gas supply tank 5; the second pressure detecting member 13 is provided in the compressor 1, and detects the pressures P2, P2 of the gaseous refrigerant in the compressor 1, that is, the pressure of the gaseous refrigerant supplied to the gas suspension bearing. The controller is respectively connected with the pressure detection part of the air supply tank 5 and the pressure detection part of the compressor 1 in a signal mode so as to start the compressor 1 after the difference value between the pressure P1 of the gaseous refrigerant in the air supply tank 5 and the pressure P2 of the refrigerant in the compressor 1 is larger than or equal to a preset pressure threshold value Pm.
After the system is stopped normally or other faults are stopped (including abnormal power failure), before the compressor 1 is started again, the air supply pump 7 is started to supply high-pressure gaseous refrigerant to the air supply tank 5, so that the gaseous refrigerant pressure of the air supply tank 5 is large enough, the initial operation pressure P0=P1-P1 is reached, until the P0 is more than or equal to Pm, the compressor 1 is started again, and the air suspension bearing is ensured to reach a suspension state before the operation of the compressor 1.
In some embodiments, the condenser further comprises a third pressure detecting component 14 disposed on the condenser 2, for detecting the pressure P3 of the refrigerant in the condenser 2; the controller is in signal connection with the third pressure detecting part 14, and after the compressor 1 is normally started, the air supply mode is switched according to the difference value between the pressure P3 of the refrigerant in the condenser 2 and the pressure P2 of the gaseous refrigerant in the compressor 1.
During normal operation, the gas refrigerant main flow path 4 supplies gas, the condensing pressure P3 of the condenser 2 is equal to the pressure P1 of the gas refrigerant in the gas supply tank 5, when the gas supply pump 7 fails, the condensing pressure of the condenser 2 is reduced, namely P3-P2 is less than Pm, at the moment, the second electromagnetic valve 10 is opened, the first electromagnetic valve 8 is closed, and the high-pressure gas refrigerant of the condenser 2 participates in gas supply through the gas refrigerant branch flow path 9.
The air suspension bearing is a porous graphite bearing, and although the bearing has almost no friction, a certain heating value still exists between the bearing and the air supply, so that the air suspension bearing plays a role of not only suspending the bearing but also cooling the bearing to reduce the heating value of the bearing for the air supply source.
In some embodiments, the air supply system further includes a liquid refrigerant main flow path 15, a fourth electromagnetic valve 16, and a cooling plate exchanger 17, where the liquid refrigerant main flow path 15 includes an inlet end for introducing the liquid refrigerant condensed by the condenser 2 and an outlet end for outputting the liquid refrigerant; the fourth electromagnetic valve 16 is arranged in the liquid refrigerant main flow path 15 to control the on-off of the liquid refrigerant main flow path 15; the air inlet of the cooling plate exchanger 17 is communicated with the outlet end of the gaseous refrigerant main flow path 4 and the outlet end of the gaseous refrigerant branch flow path 9, and the air outlet of the cooling plate exchanger 17 is communicated with the air inlet of the air supply tank 5; the liquid inlet of the cooling plate exchanger 17 is communicated with the outlet end of the liquid refrigerant main flow path 15, and the liquid outlet of the cooling plate exchanger 17 is communicated with the evaporator 3.
When the system is shut down due to the failure of the air supply pump 7, the fourth electromagnetic valve 16 should be in a closed state, so that the high-pressure gaseous refrigerant of the condenser 2 can be kept in a state before the shut down to the greatest extent, and the pressure relief of the condenser 2 is prevented or slowed down.
When the gaseous refrigerant at the air supply end needs to be cooled, the fourth electromagnetic valve 16 is opened, so that part of the liquid refrigerant of the condenser 2 enters the cooling plate exchanger 17 from the liquid refrigerant main flow path 15, the liquid refrigerant and the gaseous refrigerant are subjected to heat conduction in the cooling plate exchanger 17, and the gaseous refrigerant at the air supply end is cooled through the heat conduction of the cooling plate exchanger 17.
In some embodiments, the apparatus further comprises a first temperature detecting member 18 provided in the gas supply tank 5 for detecting the gas supply temperature T1; controller and first temperature detecting means 18 and fourth solenoid valve 16 are respectively connected in signal to ensure that the air supply temperature T1 is greater than the first temperature threshold T m1 The fourth solenoid valve 16 is controlled to open.
When T1 is less than or equal to T m1 The air supply temperature is normal, the fourth electromagnetic valve 16 is closed, and the liquid refrigerant main flow path 15 is not required to be opened to cool the gaseous refrigerant at the air supply end; when T1 > T m1 When the air supply temperature is too high, the fourth electromagnetic valve 16 is opened, and the temperature is reduced through heat conduction of the cooling plate exchanger 17.
In some embodiments, the cooling electronic expansion valve 19 is arranged on the liquid refrigerant main flow path 15, and the controller is in signal connection with the cooling electronic expansion valve 19 so as to ensure that the air supply temperature is less than the second temperature threshold T m2 The opening degree of the cooling electronic expansion valve 19 is adjusted at the time T m2 ＜T m1 。
When T1 > T m1 At this time, the opening degree of the cooling electronic expansion valve 19 is gradually increased to lower the supply air temperature; when T is m2 ≤T1≤T m1 The opening of the cooling electronic expansion valve 19 is maintained during the process; when T1 is less than T m2 In this case, the opening of the electronic expansion valve 19 is gradually reduced, and the flow of the refrigerant for cooling is reduced, so as to increase the refrigerating capacity of the main refrigerating flow path of the system, that is, the refrigerating capacity of the condenser 2 entering the evaporator 3 through the third electromagnetic valve 11, thereby increasing the energy efficiency.
In some embodiments, the air supply system further includes a liquid refrigerant branch flow path 20, a throttling element 21, and a fifth electromagnetic valve 22, wherein the liquid refrigerant branch flow path 20 includes an inlet end and an outlet end which are respectively communicated with an inlet and an outlet of the cooling electronic expansion valve 19; the throttling element 21 is arranged on the liquid refrigerant branch flow path 20; a fifth electromagnetic valve 22 provided in the liquid refrigerant branch passage 20; the controller is in signal connection with the fifth solenoid valve 22 to control the fifth solenoid valve 22 to open when the cooling electronic expansion valve 19 is opened to a maximum opening and the supply air temperature is still greater than the first temperature threshold.
When the electronic expansion valve 19 is opened to the maximum opening degree and T1 is still greater than T m1 When the liquid state cooling medium flows, the fifth electromagnetic valve 22 is controlled to be opened to increase the cooling medium flow of the liquid state cooling medium flow path, and the cooling effect is further improved through the throttling element 21; when T is m2 ≤T1≤T m1 When in use, the cooling can be gradually reducedBut the opening degree of the electronic expansion valve 19, T1 is still smaller than T if the electronic expansion valve 19 is closed to the minimum opening degree m1 The fifth solenoid valve 22 is closed to increase the refrigerating capacity of the main refrigerating flow path of the system and improve the energy efficiency.
Through the control, the effective control of the air supply temperature can be realized, the loss of ineffective cooling flow is avoided, and the refrigerating capacity of a main refrigerating flow path of the cold system is improved to the greatest extent while the proper air supply temperature is ensured.
Alternatively, the throttling element 21 may employ a capillary tube to reduce cost.
In some embodiments, a second one-way valve 23 is further included in the line between the compressor 1 and the condenser 2, the inlet end of the second one-way valve 23 being in communication with the discharge port of the compressor 1, the outlet end of the second one-way valve 23 being in communication with the condenser 2.
In some embodiments, the refrigerant circulation system further comprises a first filter 24 provided in the gaseous refrigerant branch flow path 9, a second filter 25 provided in the gaseous refrigerant main flow path 4, and a third filter 26 provided in the flow path between the gas supply tank 5 and the gas suspension bearing of the compressor 1.
In some embodiments, a throttle electronic expansion valve 27 is provided in the flow path between the condenser 2 and the evaporator 3 to throttle and depressurize the high-pressure liquid refrigerant exiting the condenser 2 to an evaporation pressure while adjusting the flow rate of the liquid refrigerant entering the evaporator 3.
As shown in fig. 2, the embodiment of the present application provides a control method of a refrigerant circulation system as described above, including the following steps:
s101, acquiring a stop signal of a refrigerant circulation system.
S102, if the stop signal is that the air supply pump 7 is stopped by fault, the second electromagnetic valve 10 is opened, and the third electromagnetic valve 11 is closed, so that the gaseous refrigerant is continuously supplied to the air suspension bearing. As previously mentioned, the first solenoid valve 8 may also be opened at this time.
S103, if the shutdown signal is a system normal shutdown or other fault shutdown, the second electromagnetic valve 10 and the third electromagnetic valve 11 are closed, and the air supply pump 7 and the first electromagnetic valve 8 are controlled to be closed after the compressor 1 is stopped for a preset time, so as to supply the gaseous refrigerant to the air suspension bearing before the compressor 1 completely stops rotating.
By the control method, when the system is stopped due to the failure of the air supply pump 7, the high-pressure gaseous refrigerant of the condenser 2 can be kept in a state before the stop to the greatest extent, the pressure release of the condenser 2 is prevented or slowed down, the high-pressure gaseous refrigerant is favorably provided for the air suspension bearing after the stop of the compressor 1 and before the complete stop of the movement, the serious abrasion of the air suspension bearing due to insufficient air supply is avoided, and the reliability and the precision of the air suspension bearing are ensured. When the system is stopped normally or due to other faults, the air supply pump 7 and the first electromagnetic valve 8 are closed in a delayed mode, so that the refrigerant in the condenser 2 is conveyed to the air supply tank 5 and the air suspension bearing more, and the situation that the air suspension bearing is worn due to insufficient air supply is avoided.
In some embodiments, the control method further comprises:
acquiring the air supply temperature; if the air supply temperature is greater than the first temperature threshold, the fourth electromagnetic valve 16 is opened to enable the liquid refrigerant and the gaseous refrigerant to be subjected to heat conduction in the cooling plate exchanger 17, and the cooling of the gaseous refrigerant at the air supply end is realized through the heat conduction of the cooling plate exchanger 17.
In some embodiments, the control method further comprises:
if the supply air temperature is greater than the first temperature threshold value, the fourth solenoid valve 16 is opened, and the opening degree of the cooling electronic expansion valve 19 is gradually increased until it is maximum.
If the supply air temperature is less than the second temperature threshold value, which is less than the first temperature threshold value, the opening degree of the cooling electronic expansion valve 19 is gradually reduced.
If the supply air temperature is between the second temperature threshold value and the first temperature threshold value, the opening degree of the cooling electronic expansion valve 19 is kept unchanged.
Through the control, the effective control of the air supply temperature can be realized, the loss of ineffective cooling flow is avoided, and the refrigerating capacity of a main refrigerating flow path of the cold system is improved to the greatest extent while the proper air supply temperature is ensured.
According to the embodiment, the application further provides refrigeration equipment, which comprises the refrigerant circulation system, and the bearing can be supplied with air all the time when the static pressure gas suspension compressor 1 is stopped normally, stopped by fault, abnormally powered off or the air supply pump 7 is stopped by fault, so that reliable and stable operation of the unit is ensured. Meanwhile, the effective control of the air supply temperature can be realized, the loss of ineffective cooling flow is avoided, and the refrigerating capacity of a main refrigerating flow path of the cold system is improved to the greatest extent while the proper air supply temperature is ensured.
It is to be understood that the terminology used herein is for the purpose of describing particular example embodiments only, and is not intended to be limiting. As used herein, the singular forms "a", "an" and "the" are intended to include the plural forms as well, unless the context clearly indicates otherwise. The terms "comprises," "comprising," "includes," "including," and "having" are inclusive and therefore specify the presence of stated features, steps, operations, elements, and/or components, but do not preclude the presence or addition of one or more other features, steps, operations, elements, components, and/or groups thereof. The method steps, processes, and operations described herein are not to be construed as necessarily requiring their performance in the particular order described or illustrated, unless an order of performance is explicitly stated. It should also be appreciated that additional or alternative steps may be used.
Although the terms first, second, third, etc. may be used herein to describe various elements, components, regions, layers and/or sections, these elements, components, regions, layers and/or sections should not be limited by these terms. These terms may be only used to distinguish one element, component, region, layer or section from another region, layer or section. Terms such as "first," "second," and other numerical terms when used herein do not imply a sequence or order unless clearly indicated by the context. Thus, a first element, component, region, layer or section discussed below could be termed a second element, component, region, layer or section without departing from the teachings of the example embodiments.
The foregoing is merely a specific embodiment of the application to enable one skilled in the art to understand or practice the application. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the generic principles defined herein may be applied to other embodiments without departing from the spirit or scope of the application. Thus, the present application is not intended to be limited to the embodiments shown herein but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims (13)

1. A refrigerant circulation system including a compressor (1) having an air suspension bearing, a condenser (2) for condensing a refrigerant compressed by the compressor (1), an evaporator (3) for evaporating the refrigerant condensed in the condenser (2), and an air supply system for supplying a gaseous refrigerant to the air suspension bearing, the air supply system comprising:
a main flow path (4) for gaseous refrigerant, which comprises an inlet end communicated with the condenser (2) for introducing the gaseous refrigerant and an outlet end for outputting the gaseous refrigerant;
the gas supply tank (5) comprises a gas inlet communicated with the outlet end of the gaseous refrigerant main flow path (4) and a gas outlet for supplying gaseous refrigerant to the gas suspension bearing;
the first one-way valve (6) is arranged in the gaseous refrigerant main flow path (4), the inlet end of the first one-way valve (6) is communicated with the condenser (2), and the outlet end of the first one-way valve (6) is communicated with the air supply tank (5);
an air supply pump (7) provided in the main flow path (4) for supplying the gaseous refrigerant in the condenser (2) to the air supply tank (5);
a first electromagnetic valve (8) provided in the main flow path (4) for the gaseous refrigerant, the first electromagnetic valve (8) having an inlet end communicating with an inlet port of the main flow path (4) for the gaseous refrigerant and an outlet end communicating with the air supply pump (7);
a gaseous refrigerant branch passage (9) including an inlet end communicating with the inlet end of the first solenoid valve (8) and an outlet end communicating with the outlet end of the first check valve (6);
a second electromagnetic valve (10) provided in the gaseous refrigerant branch passage (9);
the third electromagnetic valve (11) is arranged in a pipeline between the condenser (2) and the evaporator (3) to control the on-off of the condenser (2) and the evaporator (3); and
and the controller is respectively in signal connection with the first electromagnetic valve (8), the second electromagnetic valve (10) and the third electromagnetic valve (11) so as to open the second electromagnetic valve (10) and close the third electromagnetic valve (11) after the air supply pump (7) stops due to fault.
2. The refrigerant circulation system according to claim 1, wherein the gas supply system further comprises:
a first pressure detection means (12) provided in the gas supply tank (5) for detecting the pressure of the gaseous refrigerant in the gas supply tank (5);
a second pressure detection means (13) provided in the compressor (1) for detecting the pressure of the gaseous refrigerant in the compressor (1);
the controller is in signal connection with the pressure detection component of the air supply tank (5) and the pressure detection component of the compressor (1) respectively, so that the compressor (1) is started after the difference value between the pressure of the refrigerant in the air supply tank (5) and the pressure of the refrigerant in the compressor (1) is greater than or equal to a preset pressure threshold value.
3. The refrigerant circulation system according to claim 2, wherein the gas supply system further includes a third pressure detecting member (14) provided on the condenser (2) for detecting a pressure of the refrigerant in the condenser (2);
the controller is in signal connection with the pressure detection component of the condenser (2), and after the compressor (1) operates normally, the air supply mode is switched according to the difference value between the pressure of the refrigerant in the condenser (2) and the pressure of the gaseous refrigerant in the compressor (1).
4. The refrigerant circulation system according to claim 1, wherein the gas supply system further comprises:
a liquid refrigerant main channel (15) including an inlet end for introducing the liquid refrigerant condensed by the condenser (2) and an outlet end for outputting the liquid refrigerant;
a fourth electromagnetic valve (16) arranged on the liquid refrigerant main flow path (15) for controlling the on-off of the liquid refrigerant main flow path (15);
the air inlet of the cooling plate exchanger (17) is communicated with the outlet end of the gaseous refrigerant main flow path (4) and the outlet end of the gaseous refrigerant branch flow path (9), and the air outlet of the cooling plate exchanger (17) is communicated with the air inlet of the air supply tank (5); the liquid inlet of the cooling plate exchanger (17) is communicated with the outlet end of the liquid refrigerant main flow path (15), and the liquid outlet of the cooling plate exchanger (17) is communicated with the evaporator (3).
5. The refrigerant cycle system as recited in claim 4, further comprising a first temperature detection means (18) provided in said gas supply tank (5) for detecting a gas supply temperature;
the controller is respectively in signal connection with the first temperature detection component (18) and the fourth electromagnetic valve (16) so as to control the fourth electromagnetic valve (16) to be opened when the air supply temperature is greater than a first temperature threshold value.
6. The refrigerant circulation system according to claim 5, further comprising a cooling electronic expansion valve (19) provided in the liquid refrigerant main flow path (15), the controller being in signal connection with the cooling electronic expansion valve (19) to adjust an opening degree of the cooling electronic expansion valve (19) when the supply air temperature is less than a second temperature threshold value, the second temperature threshold value being less than the first temperature threshold value.
7. The refrigerant circulation system according to claim 6, wherein the gas supply system further comprises:
a liquid refrigerant branch flow path (20) which comprises an inlet end and an outlet end which are respectively communicated with an inlet and an outlet of the cooling electronic expansion valve (19);
a throttle element (21) provided in the liquid refrigerant branch passage (20);
a fifth electromagnetic valve (22) provided in the liquid refrigerant branch passage (20);
the controller is in signal connection with the fifth electromagnetic valve (22) to control the fifth electromagnetic valve (22) to be opened when the cooling electronic expansion valve (19) is opened to the maximum opening degree and the air supply temperature is still larger than a first temperature threshold value.
8. Refrigerant circulation system according to claim 1, characterized in that it further comprises a second non-return valve (23) arranged in the line between the compressor (1) and the condenser (2), the inlet end of the second non-return valve (23) being in communication with the discharge opening of the compressor (1), the outlet end of the second non-return valve (23) being in communication with the condenser (2).
9. Refrigerant circulation system according to claim 1, characterized in that the refrigerant circulation system further comprises a first filter (24) arranged in the gaseous refrigerant branch flow path (9), a second filter (25) arranged in the gaseous refrigerant main flow path (4) and a third filter (26) arranged in the flow path between the gas supply tank (5) and the gas suspension bearing of the compressor (1).
10. The control method of a refrigerant cycle system as claimed in any one of claims 1 to 9, comprising:
acquiring a stop signal of the refrigerant circulation system;
if the stop signal is that the air supply pump (7) fails to stop, the second electromagnetic valve (10) is opened, and the third electromagnetic valve (11) is closed, so that the gaseous refrigerant is continuously supplied to the air suspension bearing;
if the shutdown signal is a system normal shutdown or other fault shutdown, the second electromagnetic valve (10) and the third electromagnetic valve (11) are closed, and the air supply pump (7) and the first electromagnetic valve (8) are controlled to be closed after the compressor (1) is stopped for a preset time, so that the gaseous refrigerant is provided for the air suspension bearing before the compressor (1) completely stops rotating.
11. The control method according to claim 10, characterized in that the gas supply system further comprises a liquid refrigerant main flow path (15), a fourth electromagnetic valve (16) provided in the liquid refrigerant main flow path (15), a cooling plate exchanger (17), and a first temperature detecting member (18) provided in the gas supply tank (5), the gas inlet of the cooling plate exchanger (17) being communicated with both the outlet end of the gaseous refrigerant main flow path (4) and the outlet end of the gaseous refrigerant branch flow path (9), the gas outlet of the cooling plate exchanger (17) being communicated with the gas inlet of the gas supply tank (5); the liquid inlet of the cooling plate exchanger (17) is communicated with the outlet end of the liquid refrigerant main flow path (15), the liquid outlet of the cooling plate exchanger (17) is communicated with the evaporator (3), and the control method further comprises the following steps:
acquiring the air supply temperature;
and if the air supply temperature is greater than a first temperature threshold, opening the fourth electromagnetic valve (16).
12. The control method according to claim 11, characterized in that the gas supply system further includes a cooling electronic expansion valve (19) provided on the liquid refrigerant main flow path (15), the control method further comprising:
if the air supply temperature is greater than a first temperature threshold value, opening the fourth electromagnetic valve (16) and gradually increasing the opening of the cooling electronic expansion valve (19) until the opening is maximum;
gradually decreasing the opening of the cooling electronic expansion valve (19) if the supply air temperature is less than a second temperature threshold, the second temperature threshold being less than the first temperature threshold;
if the supply air temperature is between the second temperature threshold and the first temperature threshold, the opening degree of the cooling electronic expansion valve (19) is kept unchanged.
13. A refrigeration appliance, comprising: the refrigerant circulation system as claimed in any one of claims 1 to 9.
CN202311792564.9A 2023-12-22 2023-12-22 Refrigerant circulation system, control method thereof and refrigeration equipment Pending CN117847813A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN202311792564.9A CN117847813A (en) 2023-12-22 2023-12-22 Refrigerant circulation system, control method thereof and refrigeration equipment

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN202311792564.9A CN117847813A (en) 2023-12-22 2023-12-22 Refrigerant circulation system, control method thereof and refrigeration equipment

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Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN118273940A (en) * 2024-05-24 2024-07-02 合肥通用机械研究院有限公司 Performance test system and test method for air suspension refrigeration compressor
CN119289552A (en) * 2024-06-24 2025-01-10 广州汽车集团股份有限公司 Refrigeration system and control method of refrigeration system

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN118273940A (en) * 2024-05-24 2024-07-02 合肥通用机械研究院有限公司 Performance test system and test method for air suspension refrigeration compressor
CN118273940B (en) * 2024-05-24 2024-07-30 合肥通用机械研究院有限公司 Performance test system and test method for air suspension refrigeration compressor
CN119289552A (en) * 2024-06-24 2025-01-10 广州汽车集团股份有限公司 Refrigeration system and control method of refrigeration system

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