EP2873934A1 - Erwärmungsvorrichtung mit einer wärmepumpe - Google Patents

Erwärmungsvorrichtung mit einer wärmepumpe Download PDF

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Publication number
EP2873934A1
EP2873934A1 EP20130816457 EP13816457A EP2873934A1 EP 2873934 A1 EP2873934 A1 EP 2873934A1 EP 20130816457 EP20130816457 EP 20130816457 EP 13816457 A EP13816457 A EP 13816457A EP 2873934 A1 EP2873934 A1 EP 2873934A1
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EP
European Patent Office
Prior art keywords
refrigerant
pressure side
side compressor
temperature
gas
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.)
Withdrawn
Application number
EP20130816457
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English (en)
French (fr)
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EP2873934A4 (de
Inventor
Motoki TANIMURA
Kosuke Watanabe
Syozo Tanaka
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Sharp Corp
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Sharp Corp
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Publication date
Application filed by Sharp Corp filed Critical Sharp Corp
Publication of EP2873934A1 publication Critical patent/EP2873934A1/de
Publication of EP2873934A4 publication Critical patent/EP2873934A4/de
Withdrawn legal-status Critical Current

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    • 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
    • F25B31/00—Compressor arrangements
    • F25B31/006—Cooling of compressor or motor
    • F25B31/008—Cooling of compressor or motor by injecting a liquid
    • 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
    • F25B41/39—Dispositions with two or more expansion means arranged in series, i.e. multi-stage expansion, on a refrigerant line leading to the same 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
    • F25B2400/13—Economisers
    • 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
    • F25B2500/19—Calculation of parameters
    • 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
    • F25B2600/2513—Expansion valves

Definitions

  • the present invention generally relates to a heat pump type heating device, more particularly, a two-stage compression heat pump type heating device provided with two compressors on a heat pump cycle.
  • Japanese Patent Laying-Open No. 8-210709 discloses a heat pump air conditioner for cold districts so as to achieve a heating operation even when the outdoor air temperature is - 20°C (Patent Document 1).
  • a scroll compressor, a four-way valve, an indoor air heat exchanger, a receiver, an outdoor refrigerant control valve, and an outdoor air heat exchanger are connected sequentially to one another via a pipe.
  • a bypass flow path for injecting liquid refrigerant into the scroll compressor is provided together with a liquid injection refrigerant control valve.
  • the liquid injection refrigerant control valve is controlled in accordance with a difference between a temperature at the discharge side of the compressor and a target discharge temperature, and the outdoor refrigerant control valve is controlled such that a difference between temperatures provided by temperature sensors provided at the front and rear sides relative to the outdoor air heat exchanger becomes a degree of superheating of the refrigerant at the refrigerant outlet of the outdoor air heat exchanger.
  • Japanese Patent Laying-Open No. 11-132575 discloses an air conditioner so as to prevent reliability of a compressor from being decreased due to introduction of liquid refrigerant into gas refrigerant flowing from a gas-liquid separator, which is inserted in a liquid pipe, back to the compressor via a gas injection bypass pipe (Patent Document 2).
  • an outdoor heat exchanger and an indoor heat exchanger are sequentially connected to the compressor, thereby forming a refrigerant circulation circuit.
  • the gas-liquid separator is inserted in the liquid pipe between the outdoor heat exchanger and the indoor heat exchanger.
  • the gas injection bypass pipe for flowing the gas refrigerant in the gas-liquid separator back to the compressor; and an opening/closing valve for opening/closing the flow path through the bypass pipe.
  • the opening/closing valve is operated to be closed when a difference between the discharge temperature of the compressor and the condensation temperature of the refrigerant circulating in the refrigerant circulation circuit becomes less than a reference temperature difference.
  • the reference temperature difference is set to be larger as the operation frequency of the compressor is higher.
  • Japanese Patent Laying-Open No. 2007-263440 discloses an air conditioning device to operate at a high operating efficiency under a low load and improve heating ability under a high load by appropriately adjusting an amount of injection of refrigerant into a compressor in a compressing process during a heating operation (Patent Document 3).
  • the air conditioning device disclosed in Patent Document 3 includes: an injection pipe for injecting part of refrigerant, which flows out from an indoor heat exchanger, to the compressor in the compression process via an injection decompression device; compressor rotation speed control means for controlling the rotation speed of the compressor in accordance with a magnitude of load; and injection control means for controlling the injection decompression device such that the degree of superheating or discharge temperature of the discharged gas at the outlet portion of the compressor becomes a target value.
  • the target value is set to be smaller as the rotation speed of the compressor controlled by the compressor rotation speed control means is higher, and is set to be larger as the rotation speed of the compressor is lower.
  • a heat pump type heating device such as an air conditioning device or a water heating device
  • a two-stage compression heat pump type heating device provided with two compressors, i.e., a low-pressure side compressor and a high-pressure side compressor, on a heat pump cycle.
  • the suction temperature and discharge temperature of the refrigerant in the high-pressure side compressor are increased to exceed the operating range of the compressor, disadvantageously.
  • an injection pipe is provided to connect a pipe path between the low-pressure side compressor and the high-pressure side compressor to a pipe path between the indoor heat exchanger (condenser) and the outdoor heat exchanger (evaporator), and then part of the refrigerant distributing in the pipe path between the indoor heat exchanger and the outdoor heat exchanger is injected, via the injection pipe, into the pipe path between the low-pressure side compressor and the high-pressure side compressor.
  • the suction temperature of the refrigerant in the high-pressure side compressor is decreased, thereby achieving an operation with maintained reliability.
  • the present invention has an object to solve the above-described problems, specifically, provide a heat pump type heating device having a simple configuration and having sufficiently improved heating ability.
  • a heat pump type heating device includes: a first heat exchanger performing heat exchange between refrigerant and heat-receiving fluid; a second heat exchanger performing heat exchange between the refrigerant and outdoor air; a low-pressure side compressor compressing the refrigerant sent from the second heat exchanger; a high-pressure side compressor compressing the refrigerant sent from the low-pressure side compressor; a first decompression device decompressing the refrigerant sent from the first heat exchanger; a gas-liquid separator separating the refrigerant sent from the first decompression device, into a gas phase and a liquid phase; a second decompression device connected to a liquid phase side of the gas-liquid separator and decompressing the refrigerant sent from the gas-liquid separator; an injection pipe path connected to a gas phase side of the gas-liquid separator and guiding the refrigerant sent from the gas-liquid separator, to a pipe path between the low-pressure side compressor and the high-pressure side compressor; and
  • the high-pressure side compressor receives the refrigerant having been brought into a saturated vapor state or a similar state as a result of merging of the refrigerant in the gas-liquid two-phase state flowing in the injection pipe path and the high-temperature and high-pressure gas phase refrigerant discharged from the low-pressure side compressor. Accordingly, an optimum amount of refrigerant can be injected between the low-pressure side compressor and the high-pressure side compressor, thereby sufficiently improving the heating ability.
  • the refrigerant flowing in the injection pipe path is brought into the gas-liquid two-phase state using the second decompression device decompressing the refrigerant sent from the gas-liquid separator, so that the heat pump type heating device can be provided with a simple configuration.
  • control unit further controls the decompression ratio of the refrigerant in the second decompression device such that a ratio of the liquid phase in the refrigerant, which flows in the injection pipe path and is in the gas-liquid two-phase state, does not become equal to or more than a predetermined value.
  • the compressor can be prevented from being decreased in reliability and operating efficiency due to the liquid refrigerant flowing into the high-pressure side compressor.
  • the heat pump type heating device further includes a first temperature detecting unit provided on the pipe path between the low-pressure side compressor and the high-pressure side compressor and detecting a temperature of the refrigerant having yet to be merged with the refrigerant flowing in the injection pipe path.
  • the control unit controls the decompression ratio of the refrigerant in the second decompression device based on a time history of the temperature of the refrigerant detected by the first temperature detecting unit.
  • the heat pump type heating device further includes: a second temperature detecting unit provided on the injection pipe path and detecting the temperature of the refrigerant flowing in the injection pipe path; and a third temperature detecting unit provided on the pipe path between the low-pressure side compressor and the high-pressure side compressor and detecting the temperature of the refrigerant having been merged with the refrigerant flowing in the injection pipe path.
  • the control unit controls the decompression ratio of the refrigerant in the second decompression device based on a difference between the temperature of the refrigerant detected by the second temperature detecting unit and the temperature of the refrigerant detected by the third temperature detecting unit.
  • the heat pump type heating device further includes a fourth temperature detecting unit provided on the pipe path between the low-pressure side compressor and the high-pressure side compressor and detecting the temperature of the refrigerant having been merged with the refrigerant flowing in the injection pipe path.
  • the control unit controls the decompression ratio of the refrigerant in the second decompression device based on a time history of the temperature of the refrigerant detected by the fourth temperature detecting unit.
  • the decompression ratio of the refrigerant in the second decompression device is controlled using various types of temperature histories and temperature differences correlated with the state of the refrigerant flowing in the injection pipe path.
  • the heat pump type heating device further includes a buffer unit provided on the pipe path, which is between the low-pressure side compressor and the high-pressure side compressor and in which the refrigerant having been merged with the refrigerant flowing in the injection pipe path flows, and storing liquid refrigerant.
  • the compressor can be more securely prevented from being decreased in reliability due to the liquid refrigerant flowing into the high-pressure side compressor.
  • a heat pump type heating device having a simple configuration and having sufficiently improved heating ability.
  • Fig. 1 is a circuit diagram showing a heat pump type heating device in a first embodiment of the present invention.
  • the heat pump type heating device in the present embodiment is representatively applied to a heat pump type water heater or a heat pump type heating machine.
  • the heat pump type heating device includes a refrigeration circuit 20 and an injection circuit 50 as its circuit configuration.
  • R410A is enclosed in refrigeration circuit 20 and injection circuit 50 as refrigerant, for example.
  • Refrigeration circuit 20 extends annularly to form a heat pump cycle.
  • an indoor side heat exchanger (condenser) 26 and an outdoor side heat exchanger (evaporator) 27 are provided on the path of refrigeration circuit 20, an indoor side heat exchanger (condenser) 26 and an outdoor side heat exchanger (evaporator) 27 are provided.
  • Indoor side heat exchanger 26 performs heat exchange between the refrigerant circulating in the heat pump cycle and heat-receiving fluid (water or air).
  • Outdoor side heat exchanger 27 performs heat exchange between the refrigerant circulating in the heat pump cycle and the external air (outdoor air).
  • a first decompression device 36, a gas-liquid separator 38 and a second decompression device 37 are further provided.
  • First decompression device 36, gas-liquid separator 38, and second decompression device 37 are provided between indoor side heat exchanger 26 and outdoor side heat exchanger 27.
  • First decompression device 36, gas-liquid separator 38 and second decompression device 37 are arranged in series in the flow direction of the refrigerant in refrigeration circuit 20.
  • first decompression device 36, gas-liquid separator 38 and second decompression device 37 are arranged in this order.
  • First decompression device 36 decompresses the refrigerant sent from indoor side heat exchanger 26.
  • First decompression device 36 is provided as a decompression device for controlling supercooling of the refrigerant in indoor side heat exchanger 26.
  • Gas-liquid separator 38 separates the refrigerant sent from first decompression device 36 into refrigerant in a gas phase state and refrigerant in a liquid phase state (liquid refrigerant).
  • Gas-liquid separator 38 includes: a gas phase refrigerant space 38a in which the refrigerant in the gas phase state is disposed; and a liquid phase refrigerant space 38b in which the refrigerant in the liquid phase state is disposed.
  • Second decompression device 37 is connected to liquid phase refrigerant space 38b of gas-liquid separator 38 via a pipe. Second decompression device 37 decompresses the liquid refrigerant sent from gas-liquid separator 38. Second decompression device 37 is provided as a decompression device for controlling a degree of superheating of the refrigerant in outdoor side heat exchanger 27 and an amount of injection refrigerant provided by injection circuit 50 described below. In the present embodiment, expansion valves are used as first decompression device 36 and second decompression device 37.
  • a low-pressure side compressor 31 and a high-pressure side compressor 32 are further provided.
  • Low-pressure side compressor 31 and high-pressure side compressor 32 are provided between outdoor side heat exchanger 27 and indoor side heat exchanger 26.
  • Low-pressure side compressor 31 and high-pressure side compressor 32 are arranged in series in the flow direction of the refrigerant in refrigeration circuit 20.
  • Low-pressure side compressor 31 compresses the refrigerant, which has a low pressure and is sent from outdoor side heat exchanger 27, to an intermediate pressure.
  • High-pressure side compressor 32 further compresses, to a high pressure, the refrigerant having the intermediate pressure and sent from low-pressure side compressor 31.
  • low-pressure side compressor 31 is a variable displacement type compressor capable of controlling the discharge displacement of the refrigerant (for example, an inverter compressor capable of changing the rotation speed), and high-pressure side compressor 32 is a constant rotation speed type compressor.
  • low-pressure side compressor 31 and high-pressure side compressor 32 may be of the variable displacement type, and there may be employed a combination of a constant rotation speed low-pressure side compressor and a variable displacement high-pressure side compressor or a combination of a variable displacement low-pressure side compressor and a variable displacement high-pressure side compressor.
  • a variable displacement type low-pressure side compressor provides a wider operable range under a high load.
  • Injection circuit 50 is constructed of an injection pipe path 51 in which the refrigerant can be distributed.
  • Injection pipe path 51 is provided to guide part of the refrigerant separated to come into gas phase refrigerant space 38a of gas-liquid separator 38, to refrigeration circuit 20 between low-pressure side compressor 31 and high-pressure side compressor 32.
  • injection pipe path 51 is provided to have both ends respectively connected to gas phase refrigerant space 38a of gas-liquid separator 38 and refrigeration circuit 20 between low-pressure side compressor 31 and high-pressure side compressor 32.
  • Injection pipe path 51 has a refrigerant inlet connected to gas phase refrigerant space 38a of gas-liquid separator 38, and has a refrigerant outlet connected to refrigeration circuit 20 between low-pressure side compressor 31 and high-pressure side compressor 32.
  • no opening/closing valve for permitting/blocking the flow of the refrigerant or no flow adjusting valve capable of adjusting a refrigerant flow rate is provided on injection pipe path 51.
  • buffer unit 41 and buffer unit 42 are further provided.
  • Each of buffer unit 41 and buffer unit 42 is constructed of an accumulator capable of storing liquid refrigerant therein.
  • buffer unit 41 is provided between outdoor side heat exchanger 27 and low-pressure side compressor 31.
  • buffer unit 42 is provided between low-pressure side compressor 31 and high-pressure side compressor 32.
  • connection portion 53 Assuming that a position of refrigeration circuit 20 to which injection pipe path 51 is connected is a "connection portion 53", buffer unit 42 is provided between connection portion 53 and high-pressure side compressor 32.
  • Buffer unit 41 and buffer unit 42 are provided to prevent the reliability of the compressors from being decreased due to introduction of liquid refrigerant into low-pressure side compressor 31 and high-pressure side compressor 32.
  • Fig. 2 is a Mollier diagram showing a refrigerating cycle by the heat pump type heating device in Fig. 1 .
  • the Mollier diagram is also called a "P-h diagram", and the vertical axis represents a pressure [MPa] whereas the horizontal axis represents a specific enthalpy [kJ/kg].
  • the Mollier diagram is a diagram showing characteristics specific to the refrigerant used for the refrigerating cycle, such as pressure, specific enthalpy, temperature, phase state, enthalpy, and specific volume of the refrigerant.
  • Refrigerant states A to H shown in Fig. 2 respectively correspond to refrigerant states A to H in Fig. 1 .
  • gas refrigerant (state A) discharged from high-pressure side compressor 32 flows into indoor side heat exchanger (condenser) 26, and becomes a condensed high-temperature liquid refrigerant (state B).
  • state C the pressure and temperature of the refrigerant is decreased.
  • the refrigerant flows into gas-liquid separator 38, and is separated into the gas phase and the liquid phase.
  • state D the pressure and temperature of the refrigerant is further decreased
  • state E the pressure and temperature of the refrigerant is further decreased
  • state F the refrigerant absorbs heat from the external air to evaporate
  • state F the refrigerant in state F flows into low-pressure side compressor 31 and is compressed to the intermediate pressure (state G).
  • the refrigerant (injection refrigerant) separated to come into gas phase refrigerant space 38a of gas-liquid separator 38 passes through injection pipe path 51, and is then merged with the refrigerant discharged from low-pressure side compressor 31.
  • the temperature of the injection refrigerant is lower than the temperature of the refrigerant discharged from low-pressure side compressor 31, so that the temperature of the refrigerant having been merged with the injection refrigerant is decreased (state H).
  • the compression ratio becomes large, but heating (warming) ability can be secured without abnormally increasing the discharge temperature, by injecting the injection refrigerant into the refrigerant having the intermediate pressure so as to increase the refrigerant flow rate at a stage after the compression process performed by low-pressure side compressor 31 and before the compression process performed by high-pressure side compressor 32.
  • the injection refrigerant With the effect provided by the injection refrigerant, sufficient heating ability can be obtained even when the external air temperature is a very low temperature of about -20°C, for example.
  • the heat pump type heating device further includes a temperature detecting unit 61 and a control unit 46.
  • Temperature detecting unit 61 is provided between low-pressure side compressor 31 and high-pressure side compressor 32.
  • Temperature detecting unit 61 is provided between low-pressure side compressor 31 and connection portion 53.
  • Temperature detecting unit 61 detects the temperature of the refrigerant discharged from low-pressure side compressor 31 and having yet to be merged with the refrigerant flowing in injection pipe path 51. Based on a time history of the temperature of the refrigerant detected by temperature detecting unit 61, control unit 46 controls the decompression ratio of the refrigerant in second decompression device 37.
  • the injection refrigerant is brought from the state in which the injection refrigerant is only in the gas phase to a gas-liquid two-phase state just after the liquid phase is started to be mixed.
  • the heating ability can be increased with an appropriate amount of injection refrigerant being maintained irrespective of a magnitude of load of the compressors.
  • second decompression device 37 provided at the upstream side relative to outdoor side heat exchanger 27 in the flow direction of the refrigerant during the heating operation is used instead of providing, on injection pipe path 51, a device for controlling the state of the injection refrigerant, so as to obtain an effect comparable to that in the case where a decompression device is provided on the injection pipe path to directly control the flow rate of the injection refrigerant.
  • the device can be constructed inexpensively.
  • the rotation speed of a compressor is an amount of operation with which heating ability can be adjusted most directly, so that the rotation speed of variable displacement type low-pressure side compressor 31 is controlled in accordance with a load.
  • the rotation speed of low-pressure side compressor 31 is increased/decreased in accordance with a deviation between a target heating temperature set by a user or a target heating temperature set in advance in the device and a measured heating temperature.
  • Fig. 3 shows a flowchart of control over the amount of the injection refrigerant in the heat pump type heating device in Fig. 1 .
  • the control flow shown in the figure is performed by control unit 46.
  • the following controls are performed: control over the rotation speed of low-pressure side compressor 31; control over supercooling at the outlet of indoor side heat exchanger 26 through adjustment of the degree of opening of first decompression device 36; and control over a degree of superheating at the outlet of outdoor side heat exchanger 27 through adjustment of the degree of opening of second decompression device 37.
  • the refrigerant enclosed is set such that the injection refrigerant is brought into the gas phase state when the series of controls are completed.
  • temperature T1 of the refrigerant discharged from low-pressure side compressor 31 is first detected by temperature detecting unit 61 and temperature T1 is stored in control unit 46 (S101).
  • the degree of opening of second decompression device 37 is decreased by an appropriate number of steps (S102).
  • the degree of opening of second decompression device 37 is decreased, the decompression ratio of the refrigerant in second decompression device 37 is increased.
  • the amount of the liquid refrigerant in gas-liquid separator 38 is increased and subsequently overflows in gas-liquid separator 38 to flow into injection pipe path 51, with the result that the refrigerant in the gas phase state in injection pipe path 51 is changed into the gas-liquid two-phase state.
  • temperature T1' of the refrigerant discharged from low-pressure side compressor 31 is detected again by temperature detecting unit 61 and temperature T1' is stored in control unit 46 (S103).
  • Control unit 46 calculates T1' - T1 and determines whether or not the resulting value is equal to or more than ⁇ T4 (S104).
  • ⁇ T4 represents a temperature difference in the refrigerant discharged from low-pressure side compressor 31 until the injection refrigerant is brought from the gas phase state into a state in which part of the gas phase is started to be changed into the liquid phase, and ⁇ T4 is specified in advance through an experiment in which the state of the injection refrigerant is observed while changing ⁇ T4.
  • t 30 sec
  • ⁇ T4 3°C.
  • control unit 46 determines whether or not the value of T1' - T1 is equal to or less than ⁇ T5 (S105).
  • ⁇ T5 represents a temperature difference in the refrigerant discharged from low-pressure side compressor 31 until the injection refrigerant is brought from the gas phase state into a state in which part of the gas phase is changed into the liquid phase and too much liquid refrigerant flows in injection pipe path 51, and ⁇ T5 is specified in advance through an experiment in which the state of the injection refrigerant is observed while changing ⁇ T5.
  • ⁇ T5 15°C.
  • Temperature T1 is detected when starting the control and is thereafter assumed as a constant, but the present invention is not limited to this. Temperature T1 can be also defined as a value detected at a certain time before T1'. For example, temperature T1 can be always variable as a temperature T1 at t seconds before T1'.
  • a difference is found between the temperature of the refrigerant discharged from low-pressure side compressor 31 before changing the degree of opening of second decompression device 37 and the temperature of the refrigerant at the same location after changing the degree of opening of second decompression device 37, and then the degree of opening of second decompression device 37 is adjusted such that the value thereof falls within an appropriate range.
  • the number of steps in adjusting the degree of opening of second decompression device 37 may be set at a small value when control precision is intended to be increased, whereas the number of steps in adjusting the degree of opening of second decompression device 37 may be set at a large value when control is performed to achieve a target degree of opening quickly.
  • the state of the refrigerant flowing into injection pipe path 51 is the gas phase as a result of the function of gas-liquid separator 38.
  • the degree of opening of second decompression device 37 is further decreased from this state, an amount of liquid refrigerant flowing out to the outdoor side heat exchanger 27 side is restricted, with the result that the liquid refrigerant overflows in gas-liquid separator 38 to flow into injection pipe path 51.
  • the liquid refrigerant flows into high-pressure side compressor 32, which is followed by liquid compression, presumably resulting in deterioration of reliability of the compressor.
  • buffer unit 42 provided at the suction side of high-pressure side compressor 32.
  • control is performed to maintain the gas-liquid two-phase state just after the injection refrigerant only in the gas phase is changed into the state in which the liquid phase is started to be mixed.
  • the state of the refrigerant before the refrigerant discharged from low-pressure side compressor 31 and the injection refrigerant are merged is changed from the gas phase + gas phase state to the gas phase + gas-liquid two-phase state, whereby the liquid refrigerant of the gas-liquid two-phase refrigerant is changed into the gas phase through the phase change.
  • the cycle can be readily controlled by controlling second decompression device 37 such that the injection refrigerant having yet to be merged with the refrigerant discharged from low-pressure side compressor 31 is brought into the state just after it is changed from the gas phase state to the gas-liquid two-phase state.
  • the supply of the injection refrigerant has a function of increasing the refrigerant flow rate at the heating side to increase the heating ability, and increases the limit of operating pressure ratio in the compressor.
  • the injection refrigerant in the liquid phase state is more effective than the injection refrigerant in the gas phase state.
  • the COP may be deteriorated and the reliability of the compressor may be decreased due to liquid compression.
  • the cycle involving the increased refrigerant flow rate at the heating side is maintained by maintaining the state just after the injection refrigerant is brought from the gas phase state into the gas-liquid two-phase state.
  • the state just after that can be readily determined based on the temperature history of the refrigerant discharged from low-pressure side compressor 31.
  • the greatest factor that determines the ability of the cycle is the suction pressure of high-pressure side compressor 32 (state H in Fig. 2 ).
  • the suction pressure being set at a value comparable to the conventional value, the refrigerant flow rate at the heating side can be increased to increase the heating ability in the present embodiment, thereby achieving the heating ability as good as or better than the conventional heating ability.
  • the starting point of the high-pressure side compression process comes closer to the saturated vapor state. Accordingly, the temperature of the refrigerant discharged from low-pressure side compressor 31 is more securely decreased by the injection refrigerant, thereby reducing the temperature of the refrigerant discharged from high-pressure side compressor 32. Accordingly, the limit of the operating pressure ratio in the compressor can be increased.
  • the control method in the present embodiment includes: the control over the rotation speed of the compressor in accordance with the heating load; the control over the injection in accordance with the temperature of the refrigerant discharged from low-pressure side compressor 31; and the control means for controlling the decompression device subsequent to indoor side heat exchanger 26 in the flow direction of the refrigerant.
  • the cycle can be controlled using the two decompression devices. Accordingly, the number of the decompression devices and control means, which are control factors, can be suppressed to the minimum and controllability can be improved.
  • Fig. 4 is a circuit diagram showing a first modification of the heat pump type heating device in Fig. 1 .
  • an internal heat exchanger 43 is further provided on the path of refrigeration circuit 20.
  • Internal heat exchanger 43 is provided between indoor side heat exchanger 26 and first decompression device 36.
  • Injection pipe path 51 is provided to pass through internal heat exchanger 43.
  • Internal heat exchanger 43 performs heat exchange between the refrigerant flowing from indoor side heat exchanger 26 and the refrigerant flowing in injection pipe path 51.
  • Fig. 5 is a graph showing a relation between the ratio of the injection amount to the amount of the refrigerant having yet to be branched in the gas-liquid separator and each of the heating ability and the COP.
  • the horizontal axis represents the ratio of the injection amount whereas the vertical axis represents experimental values of the heating ability and the COP.
  • the above-described heat pump type heating device includes: indoor side heat exchanger 26 serving as a first heat exchanger performing heat exchange between refrigerant and heat-receiving fluid; outdoor side heat exchanger 27 serving as a second heat exchanger performing heat exchange between the refrigerant and outdoor air; low-pressure side compressor 31 compressing the refrigerant sent from outdoor side heat exchanger 27; high-pressure side compressor 32 compressing the refrigerant sent from low-pressure side compressor 31; first decompression device 36 decompressing the refrigerant sent from indoor side heat exchanger 26; gas-liquid separator 38 separating the refrigerant sent from first decompression device 36, into a gas phase and a liquid phase; second decompression device 37 connected to a liquid phase side of gas-liquid separator 38 and decompressing the refrigerant sent from gas-liquid separator 38; injection pipe path 51 connected to a gas phase side of gas-liquid separator 38 and guiding the refrigerant sent from gas-liquid separator 38, to
  • a heat pump type heating device can be realized which is excellent in controllability and achieves sufficient improvement of the heating ability.
  • Described in the present embodiment are various types of modifications of the method of controlling the state of the injection refrigerant.
  • the same structures as those in the heat pump type heating device in the first embodiment are not described repeatedly.
  • Fig. 6 is a circuit diagram showing a second modification of the heat pump type heating device in Fig. 1 .
  • Fig. 7 shows a flowchart of control over the amount of the injection refrigerant in the heat pump type heating device in Fig. 6 .
  • the heat pump type heating device has a temperature detecting unit 62 and a temperature detecting unit 63 instead of temperature detecting unit 61 in Fig. 1 .
  • Temperature detecting unit 62 is provided in injection pipe path 51. Temperature detecting unit 62 detects the temperature of the refrigerant flowing in injection pipe path 51 and having yet to be merged on the pipe path between low-pressure side compressor 31 and high-pressure side compressor 32. Temperature detecting unit 63 is provided between low-pressure side compressor 31 and high-pressure side compressor 32. Temperature detecting unit 63 is provided between connection portion 53 and high-pressure side compressor 32.
  • Temperature detecting unit 63 detects the temperature of the refrigerant discharged from low-pressure side compressor 31 and merged with the refrigerant flowing in injection pipe path 51. Temperature detecting unit 63 detects the temperature of the refrigerant suctioned to high-pressure side compressor 32. Control unit 46 controls the decompression ratio of the refrigerant in second decompression device 37 based on a difference between the temperature of the refrigerant detected by temperature detecting unit 62 and the temperature of the refrigerant detected by temperature detecting unit 63.
  • the following controls are performed: control over the rotation speed of low-pressure side compressor 31; control over supercooling at the outlet of indoor side heat exchanger 26 through adjustment of the degree of opening of first decompression device 36; and control over a degree of superheating at the outlet of outdoor side heat exchanger 27 through adjustment of the degree of opening of second decompression device 37.
  • the refrigerant enclosed is set such that the injection refrigerant is brought into the gas phase state when the series of controls are completed.
  • temperature detecting unit 62 For the control over the amount of the injection refrigerant, temperature detecting unit 62 first detects temperature T2 of the refrigerant having yet to be merged with the injection refrigerant, temperature detecting unit 63 detects temperature T3 of the refrigerant suctioned to high-pressure side compressor 32, and these temperatures T2 and T3 are stored in control unit 46 (S111). Next, control unit 46 calculates T3 - T2 and determines whether or not the resulting value is more than 0 (S112). When T3 - T2 > 0 is satisfied, the degree of opening of second decompression device 37 is decreased by a certain number of steps (S113). On the other hand, when T3 - T2 ⁇ 0 is satisfied, the degree of opening of second decompression device 37 is increased by a certain number of steps (step 114).
  • the degree of opening of second decompression device 37 is made small to increase the flow rate of the injection refrigerant when the degree of superheating of outdoor side heat exchanger 27 is attained at temperature T3 of the refrigerant suctioned to high-pressure side compressor 32, as compared with temperature T2 of the injection refrigerant.
  • the degree of opening of second decompression device 37 is controlled to be increased such that the state of the refrigerant becomes saturated vapor at the suction portion of high-pressure side compressor 32.
  • the number of steps in adjusting the degree of opening of second decompression device 37 may be set at a small value when control precision is intended to be increased, whereas the number of steps in adjusting the degree of opening of second decompression device 37 may be set at a large value when control is performed to achieve a target degree of opening quickly. Further, in the present modification, whether or not the degree of superheating is attained is determined based on 0 as a reference, but in the case where one wishes to set the injection refrigerant at a small value, it may be set at a certain value T6, and it may be determined in S112 whether or not T3 - T2 > T6 is satisfied.
  • Fig. 8 is a circuit diagram showing a third modification of the heat pump type heating device in Fig. 1 .
  • Fig. 9 shows a flowchart of control over the amount of the injection refrigerant in the heat pump type heating device in Fig. 8 .
  • the heat pump type heating device has a temperature detecting unit 64 instead of temperature detecting unit 61 in Fig. 1 .
  • Temperature detecting unit 64 is provided between low-pressure side compressor 31 and high-pressure side compressor 32.
  • Temperature detecting unit 64 is provided between connection portion 53 and high-pressure side compressor 32.
  • Temperature detecting unit 64 detects the temperature of the refrigerant discharged from low-pressure side compressor 31 and merged with the refrigerant flowing in injection pipe path 51.
  • Temperature detecting unit 64 detects the temperature of the refrigerant suctioned to high-pressure side compressor 32.
  • control unit 46 controls the decompression ratio of the refrigerant in second decompression device 37.
  • control over the rotation speed of low-pressure side compressor 31 before controlling the amount of injection refrigerant, when starting the operation, the following controls are performed: control over the rotation speed of low-pressure side compressor 31; control over supercooling at the outlet of indoor side heat exchanger 26 through adjustment of the degree of opening of first decompression device 36; and control over a degree of superheating at the outlet of outdoor side heat exchanger 27 through adjustment of the degree of opening of second decompression device 37.
  • the refrigerant enclosed is set such that the injection refrigerant is brought into the gas phase state when the series of controls are completed.
  • temperature T3 of the refrigerant suctioned to high-pressure side compressor 32 is first detected by temperature detecting unit 64 and temperature T3 is stored in control unit 46 (S121).
  • the degree of opening of second decompression device 37 is decreased by an appropriate number of steps such that the decompression ratio of the refrigerant in second decompression device 37 becomes large (S122).
  • temperature T3' of the refrigerant suctioned to high-pressure side compressor 32 is detected again by temperature detecting unit 64 and temperature T3' is stored in control unit 46 (S123).
  • control unit 46 calculates T3-T3' and determines whether or not the resulting value is equal to or more than ⁇ T7 (S124).
  • ⁇ T7 represents a temperature difference in the refrigerant suctioned to high-pressure side compressor 32 until the injection refrigerant is brought from the gas phase state into a state in which part of the gas phase is started to be changed into the liquid phase, and ⁇ T7 is specified in advance through an experiment in which the state of the injection refrigerant is observed while changing ⁇ T7.
  • t 30 sec
  • ⁇ T7 3°C.
  • control unit 46 determines whether or not the value of T3 - T3' is equal to or less than ⁇ T8 (S125).
  • ⁇ T8 represents a temperature difference in the refrigerant suctioned to high-pressure side compressor 32 until the injection refrigerant is brought from the gas phase state into a state in which part of the gas phase is changed into the liquid phase and too much liquid refrigerant flows in inject pipe path 51, and ⁇ T8 is specified in advance through an experiment in which the state of the injection refrigerant is observed while changing ⁇ T8.
  • t 30 sec
  • ⁇ T8 15°C.
  • the number of steps in adjusting the degree of opening of second decompression device 37 may be set at a small value when control precision is intended to be increased, whereas the number of steps in adjusting the degree of opening of second decompression device 37 may be set at a large value when control is performed to achieve a target degree of opening quickly.
  • the present invention is applied to a heat pump type water heater, a heat pump type heating machine, or the like, for example.
  • 20 refrigeration circuit
  • 26 indoor side heat exchanger
  • 27 outdoor side heat exchanger
  • 31 low-pressure side compressor
  • 32 high-pressure side compressor
  • 36 first decompression device
  • 37 second decompression device
  • 38 gas-liquid separator
  • 38a gas phase refrigerant space
  • 38b liquid phase refrigerant space
  • 41, 42 buffer unit
  • 43 internal heat exchanger
  • 46 control unit
  • 50 injection circuit
  • 51 injection pipe path
  • 53 connection portion
  • 61, 62, 63, 64 temperature detecting unit.

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  • Engineering & Computer Science (AREA)
  • Physics & Mathematics (AREA)
  • Mechanical Engineering (AREA)
  • Thermal Sciences (AREA)
  • General Engineering & Computer Science (AREA)
  • Compression-Type Refrigeration Machines With Reversible Cycles (AREA)
  • Air Conditioning Control Device (AREA)
EP13816457.9A 2012-07-10 2013-07-05 Erwärmungsvorrichtung mit einer wärmepumpe Withdrawn EP2873934A4 (de)

Applications Claiming Priority (2)

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JP2012154621A JP6029879B2 (ja) 2012-07-10 2012-07-10 ヒートポンプ式加熱装置
PCT/JP2013/068515 WO2014010531A1 (ja) 2012-07-10 2013-07-05 ヒートポンプ式加熱装置

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EP2873934A1 true EP2873934A1 (de) 2015-05-20
EP2873934A4 EP2873934A4 (de) 2016-02-17

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Cited By (7)

* Cited by examiner, † Cited by third party
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EP3098550A1 (de) * 2015-05-26 2016-11-30 General Electric Technology GmbH Trocknung der braunkohle mittels wärmepumpe
CN107178925A (zh) * 2017-06-12 2017-09-19 广东美的暖通设备有限公司 空调系统和空调
US9835056B2 (en) 2015-05-26 2017-12-05 General Electric Technology Gmbh Lignite drying integration with a water/steam power cycle
US9944874B2 (en) 2015-05-26 2018-04-17 General Electric Technology Gmbh Lignite drying with a heat recovery circuit
US9944875B2 (en) 2015-05-26 2018-04-17 General Electric Technology Gmbh Lignite drying in a lignite fired power plant with a heat pump
WO2021146364A1 (en) * 2020-01-14 2021-07-22 Goodman Global Group, Inc. Heating, ventilation, and air-conditioning systems and methods
US11959669B2 (en) 2021-05-06 2024-04-16 Rolls-Royce North American Technologies Inc. Bimodal cooling system

Families Citing this family (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN105371514B (zh) * 2015-12-10 2018-05-18 珠海格力电器股份有限公司 带有中间补气的压缩系统、空调系统及其判断控制方法
JP6772703B2 (ja) * 2016-09-15 2020-10-21 富士電機株式会社 冷媒回路装置
CN115218560A (zh) * 2021-04-15 2022-10-21 芜湖美智空调设备有限公司 冷媒循环系统及空调

Family Cites Families (17)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP3080558B2 (ja) 1995-02-03 2000-08-28 株式会社日立製作所 寒冷地向けヒートポンプ空調機
JP3161389B2 (ja) 1997-10-23 2001-04-25 ダイキン工業株式会社 空気調和機
JP2001116373A (ja) * 1999-10-21 2001-04-27 Hitachi Ltd 空気調和機
JP4408413B2 (ja) * 2004-12-22 2010-02-03 日立アプライアンス株式会社 冷凍装置及びこれを用いた空気調和機
JP2007178042A (ja) * 2005-12-27 2007-07-12 Mitsubishi Electric Corp 超臨界蒸気圧縮式冷凍サイクルおよびこれを用いる冷暖房空調設備とヒートポンプ給湯機
JP2007192433A (ja) * 2006-01-17 2007-08-02 Daikin Ind Ltd 気液分離器及び該気液分離器を備えた冷凍装置
US20100275624A1 (en) * 2006-02-15 2010-11-04 Lg Electronics Inc. Air-Conditioning System And Controlling Method For The Same
JP4715561B2 (ja) * 2006-03-06 2011-07-06 ダイキン工業株式会社 冷凍装置
JP4725387B2 (ja) 2006-03-28 2011-07-13 三菱電機株式会社 空気調和装置
JP4845605B2 (ja) * 2006-06-20 2011-12-28 三洋電機株式会社 冷凍サイクル装置及びヒートポンプ式給湯機
JP2008032336A (ja) * 2006-07-31 2008-02-14 Sanyo Electric Co Ltd 二段膨張冷凍装置
JP2009014210A (ja) * 2007-06-29 2009-01-22 Daikin Ind Ltd 冷凍装置
JP2009300023A (ja) * 2008-06-16 2009-12-24 Mitsubishi Electric Corp 冷凍サイクル装置
JP2011112327A (ja) * 2009-11-30 2011-06-09 Panasonic Corp 冷暖房装置および冷凍装置
CN102128508B (zh) * 2010-01-19 2014-10-29 珠海格力电器股份有限公司 喷射器节流补气系统以及热泵或制冷系统补气方法
JP5645502B2 (ja) * 2010-06-25 2014-12-24 三菱重工業株式会社 ヒートポンプ給湯装置
CN102523753A (zh) * 2010-09-08 2012-06-27 松下电器产业株式会社 制冷循环装置

Cited By (11)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP3098550A1 (de) * 2015-05-26 2016-11-30 General Electric Technology GmbH Trocknung der braunkohle mittels wärmepumpe
EP3098548A1 (de) * 2015-05-26 2016-11-30 Alstom Technology Ltd Trocknung der braunkohle mittels wärmepumpe
US9835056B2 (en) 2015-05-26 2017-12-05 General Electric Technology Gmbh Lignite drying integration with a water/steam power cycle
US9944874B2 (en) 2015-05-26 2018-04-17 General Electric Technology Gmbh Lignite drying with a heat recovery circuit
US9944875B2 (en) 2015-05-26 2018-04-17 General Electric Technology Gmbh Lignite drying in a lignite fired power plant with a heat pump
US10392575B2 (en) 2015-05-26 2019-08-27 General Electric Company Lignite drying with closed loop heat pump
AU2016203435B2 (en) * 2015-05-26 2020-10-15 General Electric Technology Gmbh Lignite drying with closed loop heat pump
CN107178925A (zh) * 2017-06-12 2017-09-19 广东美的暖通设备有限公司 空调系统和空调
WO2021146364A1 (en) * 2020-01-14 2021-07-22 Goodman Global Group, Inc. Heating, ventilation, and air-conditioning systems and methods
US11841179B2 (en) 2020-01-14 2023-12-12 Goodman Global Group, Inc. Heating, ventilation, and air-conditioning systems and methods
US11959669B2 (en) 2021-05-06 2024-04-16 Rolls-Royce North American Technologies Inc. Bimodal cooling system

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CN104185766A (zh) 2014-12-03
EP2873934A4 (de) 2016-02-17
WO2014010531A1 (ja) 2014-01-16
JP2014016119A (ja) 2014-01-30

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