WO2018169844A1 - Pressure relief and recover circuit for refrigeration system, co2 refrigeration system and control method thereof - Google Patents

Pressure relief and recover circuit for refrigeration system, co2 refrigeration system and control method thereof Download PDF

Info

Publication number
WO2018169844A1
WO2018169844A1 PCT/US2018/021956 US2018021956W WO2018169844A1 WO 2018169844 A1 WO2018169844 A1 WO 2018169844A1 US 2018021956 W US2018021956 W US 2018021956W WO 2018169844 A1 WO2018169844 A1 WO 2018169844A1
Authority
WO
WIPO (PCT)
Prior art keywords
flow passage
pressure
gas storage
storage reservoir
pressure relief
Prior art date
Application number
PCT/US2018/021956
Other languages
English (en)
French (fr)
Inventor
Bo Zhao
Original Assignee
Carrier Corporation
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 Carrier Corporation filed Critical Carrier Corporation
Priority to DK18713542.1T priority Critical patent/DK3596410T5/da
Priority to US16/493,198 priority patent/US20200011575A1/en
Priority to EP18713542.1A priority patent/EP3596410B9/en
Publication of WO2018169844A1 publication Critical patent/WO2018169844A1/en

Links

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
    • F25B9/00—Compression machines, plants or systems, in which the refrigerant is air or other gas of low boiling point
    • F25B9/002—Compression machines, plants or systems, in which the refrigerant is air or other gas of low boiling point characterised by the refrigerant
    • F25B9/008—Compression machines, plants or systems, in which the refrigerant is air or other gas of low boiling point characterised by the refrigerant the refrigerant being carbon dioxide
    • 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
    • F25B1/10—Compression machines, plants or systems with non-reversible cycle with multi-stage compression
    • 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
    • F25B45/00—Arrangements for charging or discharging refrigerant
    • 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
    • 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
    • F25B2309/00—Gas cycle refrigeration machines
    • F25B2309/06—Compression machines, plants or systems characterised by the refrigerant being carbon dioxide
    • F25B2309/061—Compression machines, plants or systems characterised by the refrigerant being carbon dioxide with cycle highest pressure above the supercritical pressure
    • 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
    • F25B2313/00—Compression machines, plants or systems with reversible cycle not otherwise provided for
    • F25B2313/001—Compression machines, plants or systems with reversible cycle not otherwise provided for with two or more accumulators
    • 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
    • F25B2345/00—Details for charging or discharging refrigerants; Service stations therefor
    • F25B2345/001—Charging refrigerant to a cycle
    • 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
    • F25B2345/00—Details for charging or discharging refrigerants; Service stations therefor
    • F25B2345/002—Collecting refrigerant from a cycle
    • 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
    • F25B2345/00—Details for charging or discharging refrigerants; Service stations therefor
    • F25B2345/006—Details for charging or discharging refrigerants; Service stations therefor characterised by charging or discharging 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
    • F25B2400/00—General features or devices for refrigeration machines, plants or systems, combined heating and refrigeration systems or heat-pump systems, i.e. not limited to a particular subgroup of F25B
    • F25B2400/04—Refrigeration circuit bypassing means
    • F25B2400/0409—Refrigeration circuit bypassing means for the evaporator
    • 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
    • F25B2400/00—General features or devices for refrigeration machines, plants or systems, combined heating and refrigeration systems or heat-pump systems, i.e. not limited to a particular subgroup of F25B
    • F25B2400/04—Refrigeration circuit bypassing means
    • F25B2400/0415—Refrigeration circuit bypassing means for the receiver
    • 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
    • F25B2400/00—General features or devices for refrigeration machines, plants or systems, combined heating and refrigeration systems or heat-pump systems, i.e. not limited to a particular subgroup of F25B
    • F25B2400/16—Receivers
    • 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
    • F25B2400/00—General features or devices for refrigeration machines, plants or systems, combined heating and refrigeration systems or heat-pump systems, i.e. not limited to a particular subgroup of F25B
    • F25B2400/23—Separators
    • 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
    • F25B2500/00—Problems to be solved
    • F25B2500/07—Exceeding a certain pressure value in a refrigeration component or cycle
    • 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
    • F25B2600/00—Control issues
    • F25B2600/25—Control of valves
    • F25B2600/2501—Bypass 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
    • F25B2600/00—Control issues
    • F25B2600/25—Control of valves
    • F25B2600/2523—Receiver 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
    • F25B2600/00—Control issues
    • F25B2600/25—Control of valves
    • F25B2600/2525—Pressure relief 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
    • F25B43/00—Arrangements for separating or purifying gases or liquids; Arrangements for vaporising the residuum of liquid refrigerant, e.g. by heat
    • F25B43/006—Accumulators

Definitions

  • the present invention relates to the field of refrigeration, and more particularly, relates to a pressure relief and recovery loop of a refrigeration system, a carbon dioxide refrigeration system applying the loop and a pressure relief and recovery control method.
  • a pressure relief valve or a pressure relief tank is introduced in the carbon dioxide refrigeration system, so that when the overpressure condition occurs, part of a carbon dioxide refrigerant is discharged into the atmosphere via the pressure relief valve or discharged into the pressure relief tank for subsequent processing.
  • Such design relieves the overpressure problem of the carbon dioxide refrigeration system to a certain degree.
  • part of carbon dioxide in the system is discharged, which may influence refrigeration capacity of the system in the normal operating state, so maintenance personnel needs to constantly execute a refrigerant refilling action, which will increase maintenance costs.
  • a condensing unit for the overpressure problem of the carbon dioxide refrigeration system in a shutdown state, can be additionally arranged, and after the system is shut down, the condensing unit will inject cooling capacity to the system so as to prevent the occurrence of the carbon dioxide overpressure problem to the system.
  • the condensing unit will inject cooling capacity to the system so as to prevent the occurrence of the carbon dioxide overpressure problem to the system.
  • it will increase additional unit costs.
  • the present invention aims to provide a pressure relief and recovery loop capable of unloading and recovering a carbon dioxide refrigerant.
  • the present invention additionally aims to provide a carbon dioxide refrigeration system capable of unloading and recovering a carbon dioxide refrigerant.
  • the present invention further aims to provide a control method of a carbon dioxide refrigeration system capable of unloading and recovering a carbon dioxide refrigerant.
  • the present invention provides a pressure relief and recovery loop comprising: a gas storage reservoir, which is used for storing gas-phase carbon dioxide; a pressure relief flow passage, which is used for connecting the gas storage reservoir and an associated carbon dioxide refrigeration system and is used for discharging the gas-phase carbon dioxide in the carbon dioxide refrigeration system into the gas storage reservoir; and a recovery flow passage, which is used for connecting the gas storage reservoir and the associated carbon dioxide refrigeration system, and on which a driving apparatus is arranged, the recovery flow passage being used for recovering the gas-phase carbon dioxide in the gas storage reservoir into the carbon dioxide refrigeration system under the drive of the driving apparatus.
  • the present invention further provides a carbon dioxide refrigeration system comprising: a refrigeration loop, which comprises a compressor, a condenser, a throttling element and an evaporator which are connected by pipelines, wherein a high-pressure side flow passage of the refrigeration loop is formed from the downstream of the compressor to the upstream of the throttling element, and a low-pressure side flow passage of the refrigeration loop is formed from the downstream of the throttling element to the upstream of the compressor; and a pressure relief and recovery loop, which comprises: a gas storage reservoir, which is used for storing gas-phase carbon dioxide; a pressure relief flow passage, which is used for connecting the gas storage reservoir and the refrigeration loop and is used for discharging the gas-phase carbon dioxide in the refrigeration loop into the gas storage reservoir; and a recovery flow passage, which is used for connecting the gas storage reservoir and the refrigeration loop, and on which a driving apparatus is arranged, the recovery flow passage being used for
  • the present invention further provides a control method of the carbon dioxide refrigeration system as previously mentioned, which is characterized by comprising: a pressure relief control step S lOO which includes: a switch-on step S I 10: when a pressure of the high-pressure side flow passage is not smaller than a first preset pressure, and/or when a pressure of the low-pressure side flow passage is not smaller than a third preset pressure, switching on the pressure relief flow passage; a switch-off step S 120: when the pressure of the high-pressure side flow passage is not greater than a second preset pressure, and/or when the pressure of the low-pressure side flow passage is not greater than a fourth preset pressure, switching off the pressure relief flow passage; and a maintenance step S 130: when the pressure of the high-pressure side flow passage is smaller than the first preset pressure and greater than the second preset pressure, and/or when the pressure of the low-pressure side flow passage is smaller than the third preset
  • FIG. 1 is a schematic diagram of a system flow passage of a carbon dioxide refrigeration system of the present invention.
  • FIG. 1 shows a carbon dioxide refrigeration system.
  • the system includes a refrigeration loop 200 for providing cooling capacity and a pressure relief and recovery loop 100 for providing pressure relief and carbon dioxide recovery.
  • the refrigeration loop 200 includes a compressor 210, a condenser 220, a throttling element 230 and an evaporator 240 which are connected by pipelines; a high-pressure side flow passage of the refrigeration loop is formed from the downstream of the compressor 210 to the upstream of the throttling element 230; and a low-pressure side flow passage of the refrigeration loop is formed from the downstream of the throttling element 230 to the upstream of the compressor 210.
  • the above is one relatively common refrigeration loop 200, and a carbon dioxide refrigerant enters the condenser 220 to dissipate heat and is condensed after compressed via the compressor 210, then is throttled by the throttling element 230 for pressure reduction, and finally enters the evaporator 240 to absorb heat for refrigeration.
  • the pressure relief and recovery loop 100 includes: a gas storage reservoir 110, which is used for storing gas-phase carbon dioxide; a pressure relief flow passage 120, which is used for connecting the gas storage reservoir 110 and the refrigeration loop and is used for discharging the gas-phase carbon dioxide in the refrigeration loop into the gas storage reservoir 110; and a recovery flow passage 130, which is used for connecting the gas storage reservoir 110 and the refrigeration loop, and on which a recovery compressorl31 is arranged, the recovery flow passage 130 being used for recovering the gas-phase carbon dioxide in the gas storage reservoir 110 into the refrigeration loop under the drive of the recovery compressor 131.
  • the over-pressured refrigerant in the refrigeration loop 200 can be led into the gas storage reservoir 110 in the pressure relief and recovery loop 100 via the pressure relief flow passage 120, and after the system is normal, the refrigerant can be recovered into the refrigeration loop 200 under the drive of the recovery compressor 131. Therefore, not only is a refrigerant overpressure phenomenon avoided, but also a problem that the refrigerant needs to be constantly refilled is solved, and considerations to maintenance cost and system operation stability are balanced.
  • the pressure relief flow passage 120 is used for connecting the gas storage reservoir 110 and the high-pressure side flow passage of the refrigeration loop; and/or the pressure relief flow passage 120 is used for connecting the gas storage reservoir 110 and the low-pressure side flow passage of the refrigeration loop.
  • the high- pressure side flow passage and the low-pressure side flow passage of the same carbon dioxide refrigeration system have different overpressure determination standards.
  • Such arrangement can implement pressure relief on the high-pressure side flow passage when overpressure occurs on the high-pressure side and pressure relief on the low-pressure side flow passage when overpressure occurs on the low-pressure side, and such regulation mode is more targeted.
  • the pressure relief flow passage 120 can be from the gas storage reservoir 110 to a high-pressure side pressure relief junction 125 located on a flow passage between the condenser 220 and the throttling element 230 of the refrigeration loop; or alternatively, the pressure relief flow passage 120 can be from the gas storage reservoir 110 to a high-pressure side pressure relief junction 125 located on a flow passage between the condenser 220 and the compressor 210 of the refrigeration loop; and/or the pressure relief flow passage 120 can be from the gas storage reservoir 110 to a low-pressure side pressure relief junction 126 located on a flow passage between the evaporator 240 and the compressor 210 of the refrigeration loop; or alternatively, the pressure relief flow passage 120 can be from the gas storage reservoir 110 to a low-pressure side pressure relief junction 126 located on a flow passage between the evaporator 240 and the throttling element 230 of the refrigeration loop.
  • the recovery flow passage 130 is used for connecting the gas storage reservoir 110 and the low-pressure side flow passage of the refrigeration loop, so that after the system is recovered to a normal pressure state, the discharged carbon dioxide refrigerant is recovered into the refrigeration loop again, thus avoiding an influence on refrigeration capacity of the system due to insufficiency of the refrigerant.
  • the refrigerant is introduced via the low-pressure side flow passage, so that in one aspect, the resistance acting on the refrigerant when it is introduced into the system can be reduced, and in the other aspect, the refrigerant can directly enter the compressor to participate in a new round of working cycle.
  • the recovery flow passage 130 is from the gas storage reservoir 110 to a recovery junction 133 located on the flow passage between the evaporator 240 and the compressor 210 of the refrigeration loop.
  • the recovery flow passage 130 is used for connecting the gas storage reservoir 110 and a flow passage between the evaporator 240 and the gas-liquid separator 250 of the refrigeration loop.
  • the recovery flow passage 130 can be a flow passage connecting the gas storage reservoir 110 and an air suction port of the compressor 210 of the refrigeration loop.
  • an electromagnetic valve for controlling on-off of the flow passage can be arranged on the pressure relief flow passage 120.
  • the pressure relief flow passage 120 includes a high-pressure side pressure relief branch 121 and a low-pressure side pressure relief branch 122
  • the electromagnetic valve described herein is correspondingly a high-pressure side pressure relief electromagnetic valve 123 and a low-pressure side pressure relief electromagnetic valve 124, respectively.
  • a check valve 132 for preventing backflow can be arranged on the recovery flow passage 130.
  • the recovery compressor 131 on the recovery flow passage 130 may also be other driving apparatuses capable of pressurizing a gas.
  • the related pressure relief and recovery loop 100 can also be applicable to other types of carbon dioxide refrigeration systems, as long as the systems also have a demand for solving the carbon dioxide overpressure problem.
  • the pressure relief flow passage 120 and the recovery flow passage 130 in the pressure relief and recovery loop 100 and the associated carbon dioxide refrigeration system reference can also be made to the above-mentioned embodiment. Namely, the pressure relief flow passage 120 is joined to the high-pressure side flow passage or the low-pressure side flow passage of the carbon dioxide refrigeration system, and the recovery flow passage 130 is joined to the low-pressure side flow passage of the carbon dioxide refrigeration system.
  • a control method of the carbon dioxide refrigeration system is also provided herein, and optionally, it can be applicable to the above-mentioned embodiment.
  • the method includes a pressure relief control step S 100 for carrying out pressure relief when the system is over-pressured and a refrigerant recovery control step S200 for recovering the unloaded refrigerant after the system normally operates.
  • the pressure relief control step S 100 includes: a switch-on step S I 10: when a pressure of the high-pressure side flow passage is not smaller than a first preset pressure, and/or when a pressure of the low-pressure side flow passage is not smaller than a third preset pressure, which shows that the pressure in the high- pressure side flow passage and/or the low-pressure side flow passage has exceeded a normal operation range, at the moment, switching on the pressure relief flow passage; a switch-off step S 120: when the pressure of the high-pressure side flow passage is not greater than a second preset pressure, and/or when the pressure of the low-pressure side flow passage is not greater than a fourth preset pressure, which shows that the pressure in the high-pressure side flow passage and/or the low-pressure side flow passage has fallen back into the normal operation range, at the moment, switching off the pressure relief flow passage; and a maintenance step S 130: when the pressure of the high-pressure side flow passage is smaller than the first preset pressure and greater than the second preset pressure, and/or when the pressure
  • the refrigerant enters the condenser 220 to be condensed and dissipate heat after compressed via the compressor 210, then, after subjected to throttling and pressure reduction by the throttling element 230, the refrigerant enters the evaporator 240 to evaporate and absorb heat, so as to provide cooling capacity for an application environment, and subsequently, the refrigerant is dried in the gas-liquid separator, and enters the compressor 210 to start a new round of cycle.
  • the pressure of the high-pressure side flow passage (for example, a pressure at the condenser 220) is greater than or equal to the first preset pressure, it shows that the high-pressure side flow passage of the refrigeration system has an overpressure condition, and the high-pressure side pressure relief electromagnetic valve 123 should be opened; and at the moment, part of the high-pressure refrigerant flows from the high- pressure side pressure relief junction 125 into the gas storage reservoir 110 via the switched- on high-pressure side pressure relief branch 121 for temporary storage.
  • the pressure of the high-pressure side flow passage for example, a pressure at the condenser 220
  • the high-pressure side pressure relief electromagnetic valve 123 After the high-pressure side pressure relief electromagnetic valve 123 is opened transiently, the pressure of the high- pressure side flow passage can easily fall below the first preset pressure, and at the moment, it is apparently unreasonable to immediately close the high-pressure side pressure relief electromagnetic valve 123, which will result in that the pressure of the high-pressure side flow passage is always around the first preset pressure and a pressure reducing effect cannot be really achieved.
  • the high-pressure side pressure relief electromagnetic valve 123 is continuously kept open until the pressure of the high-pressure side flow passage is reduced to a pressure smaller than or equal to the second preset pressure value, at which the overpressure condition of the refrigeration system has been really regulated and controlled, and the high- pressure side pressure relief electromagnetic valve 123 can be closed. Conversely, when the pressure of the high-pressure side flow passage is greater than the second preset pressure value, the high-pressure side pressure relief electromagnetic valve 123 is still kept in a closed state until the pressure of the high-pressure side flow passage is continuously risen above the first preset pressure value, and the high-pressure side pressure relief electromagnetic valve 123 is opened again. The working cycle above is repeated.
  • the pressure of the low-pressure side flow passage (for example, the pressure at the evaporator 240) is greater than or equal to the third preset pressure, it shows that the low-pressure side flow passage of the refrigeration system has the overpressure condition, and the low-pressure side pressure relief electromagnetic valve 124 should be opened; and at the moment, part of the low-pressure refrigerant flows from the low- pressure side pressure relief junction 126 into the gas storage reservoir 110 via the switched- on low-pressure side pressure relief branch 122 for temporary storage.
  • the pressure of the low-pressure side flow passage can easily fall below the third preset pressure, and at the moment, it is also unreasonable to immediately close the low-pressure side pressure relief electromagnetic valve 124, which will result in that the pressure of the low-pressure side flow passage is always around the third preset pressure and a pressure reducing effect cannot be really achieved.
  • the low-pressure side pressure relief electromagnetic valve 124 is continuously kept open until the pressure of the low-pressure side flow passage is reduced to a pressure smaller than or equal to the fourth preset pressure value, at which the overpressure condition of the refrigeration system has been really regulated and controlled , and the low- pressure side pressure relief electromagnetic valve 124 can be closed. Conversely, when the pressure of the low-pressure side flow passage is greater than the fourth preset pressure value, the low-pressure side pressure relief electromagnetic valve 124 is still kept in a closed state until the pressure of the low-pressure side flow passage is continuously risen above the third preset pressure value, and the low-pressure side pressure relief electromagnetic valve 124 is opened again. The working cycle above is repeated.
  • pressure relief can be effectively performed on a refrigeration system when the system is over-pressured.
  • pressure relief will cause a decrease in the stock of the working refrigerant in the system. Therefore, when the system is in the normal working state, the unloaded refrigerant should also be recovered into the original refrigeration system.
  • pressure relief can be continuously normally operated or stopped.
  • the system normally operates i.e., the compressor of the refrigeration loop operates
  • the recovery compressor 131 in the recovery flow passage 130 operates, and at the moment, the refrigerant stored in the gas storage reservoir 110 flows from the recovery junction 133 into the refrigeration loop 200 via the recovery flow passage 130 and participates in the refrigeration working cycle again.
  • the recovery compressor 131 When the recovery compressor 131 has been started transiently, the pressure in the gas storage reservoir 110 can easily fall below the fifth preset pressure, and at the moment, it is apparently unreasonable to immediately stop the recovery compressor 131, which will result in that the refrigerant inadequately enters the refrigeration loop 200 to participate in refrigeration. Therefore, after the pressure in the gas storage reservoir 110 falls below the fifth preset pressure, the recovery compressor 131 is continuously kept started until the pressure in the gas storage reservoir 110 is reduced to a pressure smaller than or equal to the sixth preset pressure value, at which the refrigerant in the gas storage reservoir 110 is basically all recovered into the refrigeration loop 200, and the recovery compressor 131 can be stopped.
  • the recovery compressor 131 is still kept in a stop state until the pressure in the gas storage reservoir 110 is continuously risen above the fifth preset pressure value, and the recovery compressor 131 operates again. The working cycle above is repeated.

Landscapes

  • Engineering & Computer Science (AREA)
  • Physics & Mathematics (AREA)
  • Mechanical Engineering (AREA)
  • Thermal Sciences (AREA)
  • General Engineering & Computer Science (AREA)
  • Chemical & Material Sciences (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Safety Valves (AREA)
  • Air-Conditioning For Vehicles (AREA)
  • Devices That Are Associated With Refrigeration Equipment (AREA)
PCT/US2018/021956 2017-03-15 2018-03-12 Pressure relief and recover circuit for refrigeration system, co2 refrigeration system and control method thereof WO2018169844A1 (en)

Priority Applications (3)

Application Number Priority Date Filing Date Title
DK18713542.1T DK3596410T5 (da) 2017-03-15 2018-03-12 Co2-kølesystem og styringsfremgangsmåde dertil
US16/493,198 US20200011575A1 (en) 2017-03-15 2018-03-12 Pressure relief and recover circuit for refrigeration system, co2 refrigeration system and control method thereof
EP18713542.1A EP3596410B9 (en) 2017-03-15 2018-03-12 Co2 refrigeration system and control method thereof

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
CN201710153062.XA CN108626920A (zh) 2017-03-15 2017-03-15 制冷系统的压力卸载及回收回路、二氧化碳制冷系统及其控制方法
CN201710153062.X 2017-03-15

Publications (1)

Publication Number Publication Date
WO2018169844A1 true WO2018169844A1 (en) 2018-09-20

Family

ID=61768536

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/US2018/021956 WO2018169844A1 (en) 2017-03-15 2018-03-12 Pressure relief and recover circuit for refrigeration system, co2 refrigeration system and control method thereof

Country Status (5)

Country Link
US (1) US20200011575A1 (da)
EP (1) EP3596410B9 (da)
CN (1) CN108626920A (da)
DK (1) DK3596410T5 (da)
WO (1) WO2018169844A1 (da)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US11435123B2 (en) * 2018-12-19 2022-09-06 Toromont Industries Ltd Refrigeration system with transfer system

Families Citing this family (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN109631379B (zh) * 2018-11-26 2020-09-29 安徽正刚新能源科技有限公司 一种500/600kw-5000/6000kw冷热联供装置
CN109631444B (zh) * 2018-11-26 2020-08-21 安徽正刚新能源科技有限公司 一种二氧化碳工作容量精确调节装置
CN115406287B (zh) * 2022-08-18 2023-09-29 百穰新能源科技(深圳)有限公司 二氧化碳气液相变储能系统的存储单元、控制方法与系统
CN115751756B (zh) * 2022-11-28 2024-04-30 南京五洲制冷集团有限公司 一种利用高压储气发电的co2载冷剂储能供冷系统

Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4909042A (en) * 1987-12-10 1990-03-20 Murray Corporation Air conditioner charging station with same refrigerant reclaiming and liquid refrigerant return and method
EP0860309A2 (en) * 1997-02-24 1998-08-26 Zexel Corporation Carbon dioxide gas refrigeration cycle
JP2002195705A (ja) * 2000-12-28 2002-07-10 Tgk Co Ltd 超臨界冷凍サイクル
JP2009156531A (ja) * 2007-12-27 2009-07-16 Mitsubishi Electric Corp 冷凍装置
EP2669606A1 (en) * 2012-05-28 2013-12-04 Ecotechnics S.p.a. Method and apparatus for recovering the refrigerant from an air conditioning system
DE102014000541A1 (de) * 2014-01-15 2015-07-30 Thermea. Energiesysteme Gmbh Vorrichtung zum Erhalt des unterkritischen Betriebszustandes bei hohen Gaskühlereintrittstemperaturen eines Druckluft-Kältetrockners

Family Cites Families (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
KR20040091615A (ko) * 2002-03-28 2004-10-28 마츠시타 덴끼 산교 가부시키가이샤 냉동사이클장치
JP5523817B2 (ja) * 2009-12-25 2014-06-18 三洋電機株式会社 冷凍装置
CN201866973U (zh) * 2010-11-17 2011-06-15 重庆高环科技有限公司 恒压制冷系统

Patent Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4909042A (en) * 1987-12-10 1990-03-20 Murray Corporation Air conditioner charging station with same refrigerant reclaiming and liquid refrigerant return and method
EP0860309A2 (en) * 1997-02-24 1998-08-26 Zexel Corporation Carbon dioxide gas refrigeration cycle
JP2002195705A (ja) * 2000-12-28 2002-07-10 Tgk Co Ltd 超臨界冷凍サイクル
JP2009156531A (ja) * 2007-12-27 2009-07-16 Mitsubishi Electric Corp 冷凍装置
EP2669606A1 (en) * 2012-05-28 2013-12-04 Ecotechnics S.p.a. Method and apparatus for recovering the refrigerant from an air conditioning system
DE102014000541A1 (de) * 2014-01-15 2015-07-30 Thermea. Energiesysteme Gmbh Vorrichtung zum Erhalt des unterkritischen Betriebszustandes bei hohen Gaskühlereintrittstemperaturen eines Druckluft-Kältetrockners

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US11435123B2 (en) * 2018-12-19 2022-09-06 Toromont Industries Ltd Refrigeration system with transfer system
US11821666B2 (en) 2018-12-19 2023-11-21 Toromont Industries Ltd. Refrigeration system with transfer system

Also Published As

Publication number Publication date
EP3596410B1 (en) 2022-03-02
DK3596410T5 (da) 2022-07-25
DK3596410T3 (da) 2022-03-28
EP3596410B9 (en) 2022-06-29
CN108626920A (zh) 2018-10-09
EP3596410A1 (en) 2020-01-22
US20200011575A1 (en) 2020-01-09

Similar Documents

Publication Publication Date Title
EP3596410B1 (en) Co2 refrigeration system and control method thereof
KR100757592B1 (ko) 공조용 히트 펌프
CN105588376B (zh) 制冷系统及其控制方法、冷藏运输车
WO2008002048A1 (en) High efficiency refrigeration system for saving energy and control method the same
EP3575712B1 (en) Cooling system
CN110234944B (zh) 制冷系统
CN104848587A (zh) 变频多联式热泵系统及旁通电子膨胀阀的控制方法
US11988423B2 (en) Cooling system
EP2669588A1 (en) Air conditioning system and start-up control method therefor
WO2019052035A1 (zh) 多联式空调的控制方法、系统及计算机可读存储介质
US6925822B2 (en) Oil return control in refrigerant system
CN109282516B (zh) 风冷螺杆机组及其控制方法
JP2018200145A (ja) 制御装置、空気調和機及び制御方法
JP2016041987A (ja) 圧縮機／ポンプ切換式の冷却装置
JP2008101885A (ja) 同時加熱、冷却ヒートポンプ回路
US20180363961A1 (en) Air conditioner
WO2021048899A1 (ja) 室外ユニット及び冷凍サイクル装置
JP2015152262A (ja) 冷凍サイクル装置
WO2018079242A1 (ja) 冷凍装置、冷凍システム
KR100876285B1 (ko) 가스히트펌프 시스템
KR20090070000A (ko) 공기조화기의 과부하 방지 장치
JP6327986B2 (ja) 圧縮機／ポンプ切換式の冷却装置
JP2019158302A (ja) 熱源システム
CN107421152B (zh) 一种供冷系统及其控制方法
JP2023146975A (ja) 空気調和機

Legal Events

Date Code Title Description
121 Ep: the epo has been informed by wipo that ep was designated in this application

Ref document number: 18713542

Country of ref document: EP

Kind code of ref document: A1

NENP Non-entry into the national phase

Ref country code: DE

ENP Entry into the national phase

Ref document number: 2018713542

Country of ref document: EP

Effective date: 20191015