JPWO2017081820A1 - Air conditioning system and control method of air conditioning system - Google Patents

Abstract

The air conditioning system (100) includes a ventilation heat exchanger (26), a refrigerant circuit (21), a ventilation device (3), a detection unit (33) for detecting dew point temperature, and a refrigerant circuit (21). And a control device (101) for controlling the evaporation temperature. The refrigerant circuit (21) circulates the refrigerant through the compressor (22), the condenser (24), the expansion valve (25), and the ventilation heat exchanger (26). The ventilation device (3) supplies air, which is taken in from the outside and exchanged heat with the refrigerant by the ventilation heat exchanger (26), into the room. A detection part (33) is provided in the blower outlet of a ventilator (3), and detects the dew point temperature of supply air. The control device (101) reduces the refrigerant pressure when the dew point temperature of the supply air detected by the detection unit (33) exceeds a preset target dew point temperature of the room air. According to the present invention, it is possible to avoid a shortage of latent heat treatment and to reduce the amount of excess processing heat. Therefore, it is possible to suppress a decrease in energy saving while suppressing a decrease in comfort.

Description

  The present invention relates to an air conditioning system including a ventilation device and a control method thereof.

  An air conditioning system including an air conditioner having a refrigerant circuit (refrigeration cycle) and a ventilator is known. The refrigerant circuit of the air conditioner includes a compressor, a four-way valve, an outdoor heat exchanger, an expansion valve, and an indoor heat exchanger. The compressor, the four-way valve, the outdoor heat exchanger, the expansion valve, and the indoor heat exchanger are sequentially connected by piping. The refrigerant circulates through the refrigerant circuit.

  During the cooling operation, the high-temperature and high-pressure gas refrigerant compressed by the compressor is sent to the outdoor heat exchanger. In the outdoor heat exchanger, the refrigerant is liquefied by exchanging heat between the outdoor air and the refrigerant. The liquefied refrigerant is decompressed by the decompression device, becomes a gas-liquid two-phase state, and flows into the indoor heat exchanger. The refrigerant that has flowed into the indoor heat exchanger exchanges heat with room air and absorbs heat from the room air to gasify it. On the other hand, since indoor air is deprived of heat, indoor space is cooled. The gasified refrigerant returns to the compressor.

  The ventilator replaces indoor air with fresh outdoor air. Specifically, the outdoor air is supplied to the room while the indoor air is discharged to the outside.

  For this reason, in an air conditioning system including this type of ventilation device, outdoor air becomes a cooling load (outside air load) when the enthalpy of air (outdoor air) introduced from the outside is high during cooling. Other loads include a load generated indoors (indoor load) and a heat load that enters from the wall of the building.

  Therefore, in order to keep the indoor temperature and humidity constant, it is necessary to process the total heat load of outside air, the total heat load of indoor air, and the once-through load. The total heat load includes a latent heat load and a sensible heat load.

  For this reason, in the conventional air conditioning apparatus, the latent heat load is processed by dehumidifying the indoor air with the temperature of the indoor heat exchanger (evaporation temperature of the refrigerant) kept constant at a low temperature.

  However, in the operation in which the evaporation temperature is kept constant at a low temperature and the latent heat load is processed, there is a problem that the operation efficiency as a total of the air conditioner and the ventilator decreases.

  On the other hand, when the evaporation temperature is increased, the operation efficiency is improved, but there is a problem that the amount of latent heat treatment is insufficient, the indoor humidity is increased, and the comfort is lowered.

  Therefore, in the technique described in Japanese Patent Laid-Open No. 2009-257649 (Patent Document 1), in order to process the total heat load of the outside air, the temperature and humidity of the air supplied from the ventilator to the room are controlled to target values. Maintains comfort.

JP 2009-257649 A (Claim 1)

  However, in the technique described in Patent Document 1, the outside air once cooled and dehumidified is reheated and supplied indoors. For this reason, there exists a subject that the heat amount of sensible heat processing increases, power consumption increases, and energy saving property falls.

  The present invention has been made to solve the above-described problems, and an object of the present invention is to provide an air conditioning system capable of suppressing a decrease in energy saving while suppressing a decrease in comfort.

  The air conditioning system according to the present invention includes a first heat exchanger, a refrigerant circuit, a ventilation device, a detection unit that detects a dew point temperature, and a control device that controls the evaporation temperature of the refrigerant circuit.

  The first heat exchanger functions as an evaporator. The refrigerant circuit is configured to circulate the refrigerant through the compressor, the condenser, the expansion valve, and the first heat exchanger. The ventilator is configured to supply air, which is taken in from the outside and heat-exchanged with the refrigerant by the first heat exchanger, into the room.

  A detection part is provided in the blower outlet of a ventilator, and is comprised so that the dew point temperature of supply air may be detected. The control device is configured to reduce the refrigerant pressure when the dew point temperature of the supply air detected by the detection unit exceeds a preset target dew point temperature of the indoor air.

  According to the present invention, it is possible to avoid a shortage of latent heat treatment and to reduce the amount of excess processing heat. Therefore, it is possible to suppress a decrease in energy saving while suppressing a decrease in comfort.

1 is a schematic diagram illustrating a configuration of an air conditioning system according to Embodiment 1. FIG. 2 is a schematic diagram of a refrigerant system of the air-conditioning system in Embodiment 1. FIG. 1 is a schematic diagram illustrating a configuration of a ventilation device of an air conditioning system according to Embodiment 1. FIG. FIG. 3 is a schematic diagram in which a configuration relating to control of the refrigerant system in the first embodiment is added. It is explanatory drawing of the determination method of target evaporation temperature Te according to humidity difference (DELTA) X. It is explanatory drawing of the determination method of target evaporation temperature Te according to dew point temperature difference (DELTA) Tdp. 3 is a flowchart showing the operation of the air conditioning system according to Embodiment 1. It is an air diagram which shows the change of the air state in the air supply ventilation path A of a ventilator. FIG. 4 is a ph diagram of a second refrigerant system in the first embodiment. 6 is a flowchart illustrating a first modification of the operation of the air-conditioning system according to Embodiment 1. It is an air diagram which shows the change of the air state in the air supply ventilation path A of the ventilation apparatus in the modification 1. It is a figure which shows the relationship between the temperature efficiency (eta) t of the cooler 26, and temperature difference (DELTA) T. FIG. 4 is a diagram showing the relationship between the temperature efficiency ηt of the cooler 26 and the air volume of the supply air passage A. It is a figure which shows the relationship between the temperature efficiency (eta) t of the cooler 26, and the superheat degree SH of the cooler 26 exit. It is a figure explaining the operation | movement of the modification 3 of the air conditioning system in Embodiment 1. FIG.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. Hereinafter, a plurality of embodiments will be described. However, it is planned from the beginning of the application to appropriately combine the configurations described in the embodiments. In the drawings, the same or corresponding parts are denoted by the same reference numerals, and description thereof will not be repeated.

[Embodiment 1]
FIG. 1 is a schematic diagram showing a configuration of an air-conditioning system according to Embodiment 1 of the present invention.

  As shown in FIG. 1, the air conditioning system 100 corresponds to a plurality of indoor units 1A to 1C, an outdoor unit 2 provided corresponding to the indoor units 1A to 1C, a ventilator 3, and a ventilator 3. The outdoor unit 4 provided and the centralized controller 102 is included. In the example shown in FIG. 1, there are a plurality of indoor units and a single ventilator, but there may be a single indoor unit and a plurality of ventilators.

  The plurality of indoor units 1 </ b> A to 1 </ b> C and the outdoor unit 2 are connected by a refrigerant pipe 104. The indoor units 1A to 1C are arranged in the room 200, and the outdoor unit 2 is arranged outside the room.

  The ventilation device 3 and the outdoor unit 4 are connected by a refrigerant pipe 105. The ventilation device 3 is arranged in the room 200, and the outdoor unit 4 is arranged outside the room.

  The centralized controller 102 is connected to each of the indoor units 1 </ b> A to 1 </ b> C, the outdoor unit 2, the ventilator 3, and the outdoor unit 4 by a transmission line 103. The centralized controller 102 is provided with a setting input unit 44.

FIG. 2 is a schematic diagram of a refrigerant system of the air-conditioning system according to Embodiment 1.
As shown in FIG. 2, the air conditioning system 100 includes two refrigerant systems: a refrigerant circuit 11 that is an indoor unit system and a refrigerant circuit 21 that is a ventilator system.

  The refrigerant circuit 11 includes a compressor 12, a four-way valve 13, an outdoor heat exchanger 14, expansion valves 15A and 15B, indoor heat exchangers 16A and 16B, a blower 17 for the outdoor heat exchanger 14, And blowers 18A and 18B for the heat exchangers 16A and 16B.

  The compressor 12, the four-way valve 13, the outdoor heat exchanger 14, the expansion valves 15A and 15B, and the indoor heat exchangers 16A and 16B are sequentially connected by piping, and constitute the refrigerant circuit 11 in which the refrigerant circulates. The compressor 12, the four-way valve 13, the outdoor heat exchanger 14, and the blower 17 are installed in the outdoor unit 2. The expansion valve 15A, the indoor heat exchanger 16A, and the blower 18A are installed in the indoor unit 1A. The expansion valve 15B, the indoor heat exchanger 16B, and the blower 18B are installed in the indoor unit 1B.

  In FIG. 2, illustration of the indoor unit 1C is omitted in order to avoid complication, but the indoor unit 1C is arranged in parallel with the indoor unit 1A in the same manner as the indoor unit 1B. 14 and the four-way valve 13 are connected. The configuration of the indoor unit 1C is the same as the configuration of the indoor unit 1B.

  The refrigerant circuit 21 includes a compressor 22, a four-way valve 23, an outdoor heat exchanger 24, an expansion valve 25, a cooler 26, and a blower 27 for the outdoor heat exchanger 24. The compressor 22, the four-way valve 23, the outdoor heat exchanger 24, the expansion valve 25, and the cooler 26 are sequentially connected by a pipe to constitute a refrigerant circuit 21 in which the refrigerant circulates. The compressor 22, the four-way valve 23, the outdoor heat exchanger 24, and the blower 27 are installed in the outdoor unit 4. The expansion valve 25 and the cooler 26 are installed in the ventilation device 3.

  FIG. 2 shows a state where the four-way valves 13 and 23 are set to cooling, and the refrigerant flows in the direction indicated by the arrow.

  In the first embodiment, an air conditioning system 100 including two refrigerant systems, that is, a refrigerant circuit 11 that is an indoor unit system and a refrigerant circuit 21 that is a ventilator system, will be described. A configuration without the refrigerant circuit 11 may be used. That is, the air conditioning system 100 may be configured to include the refrigerant circuit 21, the ventilation device 3, and the centralized controller 102 (control device).

  FIG. 3 is a schematic diagram illustrating the configuration of the ventilation device of the air-conditioning system according to Embodiment 1 of the present invention.

  As shown in FIG. 3, the ventilation device 3 includes a cooler 26, a total heat exchanger 30, an air supply fan 28, and an exhaust fan 29 in the main body casing. Further, an air supply passage A and an exhaust passage B are formed independently of each other in the main body casing.

  The supply air ventilation path A is a ventilation path that takes in the outdoor air OA by the supply air blower 28 and passes it through the total heat exchanger 30 and the cooler 26 and supplies it to the room 200 as supply air SA.

  The exhaust ventilation path B is a ventilation path that takes in the room air RA by the exhaust fan 29 and passes it through the total heat exchanger 30 and exhausts it outside as the exhaust EA.

  In the following description, the air that flows through the total heat exchanger 30 in the supply air passage A and then flows into the cooler 26 is referred to as intake air IA.

  The ventilation device 3 further includes a temperature / humidity detection unit 31 that detects the dry bulb temperature and absolute humidity of the outdoor air OA, a temperature / humidity detection unit 32 that detects the dry bulb temperature and absolute humidity of the indoor air RA, and a supply And a detector 33 for detecting the dew point temperature of the air SA.

  The total heat exchanger 30 has, for example, a structure in which ventilation paths orthogonal to each other are alternately stacked. When the indoor air RA and the outdoor air OA pass through the ventilation path, total heat exchange is performed between the indoor air RA and the outdoor air OA. When the outdoor air OA passes through the total heat exchanger 30, it becomes the intake air IA. The indoor air RA becomes exhaust EA when passing through the total heat exchanger 30.

  The cooler 26 is composed of the evaporator of the refrigerant circuit as described above, and dehumidifies the air passing through the cooler 26 by cooling it below the dew point temperature.

  In addition to ventilation, the ventilator 3 has a role of processing the latent heat load of the room 200 as described above. The ventilator 3 processes the latent heat load in the room 200 by the total heat exchanger 30 and the cooler 26. That is, the supply air SA dehumidified by the ventilator 3 is replaced with room air, so that the room air is dehumidified as a whole, and the latent heat load of the room 200 is processed.

  The total heat exchanger 30 may be omitted, and the latent heat load in the room 200 may be processed only by the cooler 26.

  FIG. 4 is a schematic diagram in which a configuration related to the control of the refrigerant system in the first embodiment is added. Although not shown in FIG. 2, the refrigerant circuit 11 and the refrigerant circuit 21 are provided with various detection devices and control devices as shown in FIG.

  The air conditioning system 100 includes a cooler 26, a refrigerant circuit 21, a ventilation device 3, a detection unit 33 that detects a dew point temperature, and a control device 101 that controls the evaporation temperature of the refrigerant circuit 21. The cooler 26 functions as an evaporator. The refrigerant circuit 21 circulates the refrigerant through the compressor 22, the outdoor heat exchanger 24, the expansion valve 25, and the cooler 26. The outdoor heat exchanger 24 functions as a condenser. The ventilation device 3 exchanges heat between the outdoor air OA and the refrigerant by the cooler 26, and supplies the outdoor air OA to the room as supply air SA. The detection part 33 is provided in the blower outlet of the ventilation apparatus 3, and detects the dew point temperature of supply air SA. The control device 101 controls the evaporation temperature Te of the refrigerant circuit 21 so that the dew point temperature of the supply air SA detected by the detection unit 33 is lower than a preset target dew point temperature Tdp_in of the indoor air RA.

  The refrigerant circuit 11 includes a control unit 41 that controls the frequency of the compressor, a temperature detection unit 42 that detects the evaporation temperature, and temperature / humidity detection units 43A and 43B.

  The temperature detector 42 detects the temperature of the refrigerant sucked into the compressor 12. The temperature / humidity detection units 43A and 43B are provided in the plurality of indoor units 1A and 1B, respectively. The temperature / humidity detection units 43A and 43B detect the temperature and humidity of the intake air (room air) of the indoor units 1A and 1B, respectively.

  The control unit 41 changes the operating capacity of the compressor 22 by controlling the rotational speed (operating frequency) of the drive motor of the compressor 12. In addition, the control unit 41 acquires information on the target value of the evaporation temperature of the refrigerant circuit 11 from the centralized controller 102. And the control part 41 controls the operating frequency of the compressor 12 so that the temperature which the temperature detection part 42 detected becomes the target value of evaporation temperature. Specifically, when the detected temperature is lower than the target value, the control unit 41 decreases the operating frequency of the compressor 12. Conversely, when the detected temperature is higher than the target value, the control unit 41 increases the operating frequency of the compressor 12.

  Further, the control unit 41 transmits information on detection values of the temperature detection unit 42 and the temperature / humidity detection units 43 </ b> A and 43 </ b> B to the centralized controller 102.

  The refrigerant circuit 21 includes a control unit 51 and a temperature detection unit 52. The temperature detection unit 52 detects the temperature of the refrigerant sucked into the compressor 22. The controller 51 changes the operating capacity of the compressor 22 by controlling the rotational speed (operating frequency) of the drive motor of the compressor 22.

  In addition, the control unit 51 acquires information on the target value of the evaporation temperature of the refrigerant circuit 21 from the centralized controller 102. And the control part 51 controls the operating frequency of the compressor 22 so that the temperature which the temperature detection part 52 detected becomes the target value of evaporation temperature. Specifically, when the detected temperature is lower than the target value, the control unit 41 decreases the operating frequency of the compressor 12. Conversely, when the detected temperature is higher than the target value, the control unit 41 increases the operating frequency of the compressor 12.

  Further, the control unit 51 transmits information on the temperature / humidity detection unit 31, the temperature / humidity detection unit 32, the detection unit 33, and the temperature detection unit 52 to the centralized controller 102.

  The centralized controller 102 sets the target temperature, which is the temperature of the target air in the room 200, and the target absolute humidity, which is the absolute humidity of the target air, by the setting input unit 44.

  Further, the centralized controller 102 determines a range of the evaporation temperature of the refrigerant circuit 21 (hereinafter referred to as an evaporation temperature range), and determines a target value of the evaporation temperature within this evaporation temperature range. Details of the determination of the target value will be described later with reference to FIGS. In the setting input unit 44 of the centralized controller 102, a target temperature that is the temperature of the target air in the room 200 and a target dew point temperature that is the dew point temperature of the target air may be set.

  The temperature / humidity detection unit 31, the temperature / humidity detection unit 32, the detection unit 33, the temperature detection unit 42, the temperature / humidity detection units 43A and 43B, and the temperature detection unit 52 are a temperature sensor, a humidity sensor, a dew point meter, or the like. It is comprised by the sensor apparatus of. The control unit 51 calculates the dew point temperature of the supply air SA based on the detection result of the detection unit 33. The dew point temperature may be calculated by the centralized controller 102.

  The control unit 41, the control unit 51, and the centralized controller 102 can be realized by hardware such as a circuit device that realizes these functions, or can be realized as software executed on a computing device such as a microcomputer or CPU. You can also.

  Note that the control unit 41 and the control unit 51 may be provided in the centralized controller 102. Further, the function of the centralized controller 102 may be provided in the control unit 41 or the control unit 51.

  The centralized controller 102 and the control units 41 and 51 operate as the control device 101 in the present invention as a whole. The cooler 26 corresponds to the “first heat exchanger” in the present invention.

Next, the operation of the refrigerant circuit during the cooling operation and the heating operation will be described.
First, the operation during the cooling operation will be described. In the refrigerant circuit 11, the high-temperature and high-pressure gas refrigerant discharged from the compressor 12 passes through the four-way valve 13 and flows to the outdoor heat exchanger 14 to exchange heat with outdoor air to be condensed and liquefied. The condensed and liquefied refrigerant is decompressed by the expansion valve 15 to become a low-pressure gas-liquid two-phase refrigerant, flows into the indoor heat exchangers 16A and 16B, and exchanges heat with air to be gasified. The gasified refrigerant passes through the four-way valve 13 and is sucked into the compressor 12.

  Thereby, the indoor air sent by the blowers 18A and 18B for the indoor heat exchangers 16A and 16B is cooled and blown into the room 200, and the room 200 is cooled.

  In the refrigerant circuit 21, the high-temperature and high-pressure gas refrigerant discharged from the compressor 22 flows through the four-way valve 23 to the outdoor heat exchanger 24, and exchanges heat with the outdoor air OA that passes through the supply air passage A. To condense. The condensed and liquefied refrigerant is depressurized by the expansion valve 25 to become a low-pressure gas-liquid two-phase refrigerant, flows to the cooler 26, and exchanges heat with the outdoor air OA to be gasified. The gasified refrigerant passes through the four-way valve 23 and is sucked into the compressor 22.

  Thereby, the outdoor air OA passing through the supply air passage A is cooled by the cooler 26, the latent heat load is processed, and supplied to the room 200 as the supply air SA.

  Next, operation during heating operation will be described. During the heating operation, the four-way valve 13 is set to a state rotated 90 ° from the state shown in FIG. In the refrigerant circuit 11, the high-temperature and high-pressure gas refrigerant discharged from the compressor 12 passes through the four-way valve 13 and flows to the indoor heat exchangers 16 </ b> A and 16 </ b> B to exchange heat with room air to be condensed and liquefied. The condensed and liquefied refrigerant is decompressed by the expansion valve 15 to become a low-pressure gas-liquid two-phase refrigerant, flows to the outdoor heat exchanger 14 and exchanges heat with air to be gasified. The gasified refrigerant passes through the four-way valve 13 and is sucked into the compressor 12.

  Thereby, the indoor air sent by the blowers 18A and 18B for the indoor heat exchangers 16A and 16B is warmed and blown out into the room 200 to heat the room 200.

  In the refrigerant circuit 21, during the heating operation, the four-way valve 23 is set to a state rotated 90 ° from the state of FIG. The high-temperature and high-pressure gas refrigerant discharged from the compressor 22 flows through the four-way valve 23 to the cooler 26 and exchanges heat with the outdoor air OA passing through the supply air passage A to be condensed and liquefied. The cooler 26 operates as a condenser during heating operation.

  The refrigerant condensed and liquefied in the cooler 26 is depressurized by the expansion valve 25 to become a low-pressure gas-liquid two-phase refrigerant, flows to the outdoor heat exchanger 24, exchanges heat with air, and is gasified. The gasified refrigerant passes through the four-way valve 23 and is sucked into the compressor 22.

  Thus, the outdoor air OA passing through the supply air passage A is warmed by the cooler 26 that operates as a condenser, and the warmed air is supplied to the room 200 as the supply air SA.

The air conditioning system 100 may perform at least a cooling operation, and the four-way valves 13 and 23 can be omitted.
(Adjustment operation of the evaporation temperature of the refrigerant circuit 21)
Next, the adjustment operation of the evaporation temperature in the refrigerant circuit 21 of the air conditioning system 100 will be described. As will be described in detail later with reference to the flowchart of FIG. 7, in the adjustment operation of the evaporation temperature of the refrigerant circuit 21, the maximum evaporation temperature Te_max and the minimum evaporation temperature Te_min are determined, and the target evaporation is performed based on the humidity difference ΔX in the range between these. The temperature Te is determined. Thus, two examples of the method for determining the target evaporation temperature Te will be described.

  FIG. 5 is an explanatory diagram of a method for determining the target evaporation temperature Te according to the humidity difference ΔX. In FIG. 5, the horizontal axis indicates the humidity difference ΔX, and the vertical axis indicates the evaporation temperature. In the refrigerant circuit 21 of the air conditioning system 100, the absolute humidity x_ra [kg / kg ′] of the indoor air RA detected by the temperature / humidity detection unit 32 of FIG. 3 and the setting input unit 44 of FIG. A humidity difference ΔX (latent heat load) from the absolute humidity Xa_tgt [kg / kg ′] of the target air is calculated. Then, the target evaporation temperature Te [° C.] is determined according to the humidity difference ΔX.

  As shown in FIG. 5, the target evaporation temperature Te is determined within an evaporation temperature range between the maximum evaporation temperature Te_max [° C.] and the minimum evaporation temperature Te_min [° C.].

  The target evaporation temperature Te is set to be smaller as the humidity difference ΔX is larger in the range of 0 to X1. For example, as shown in FIG. 5, when the humidity difference ΔX is zero, the target evaporation temperature Te is set to the maximum evaporation temperature Te_max. When the humidity difference ΔX is the allowable humidity difference X1, the target evaporation temperature Te is set to the minimum evaporation temperature Te_min. The relationship between the humidity difference ΔX and the target evaporation temperature Te may be a linear relationship (straight line) as shown in FIG. 5, or may be determined by a function that decreases the inclination angle as the humidity difference ΔX decreases. Can be set.

  The target evaporation temperature Te can also be determined by other methods. FIG. 6 is an explanatory diagram of a method for determining the target evaporation temperature Te according to the dew point temperature difference ΔTdp. In FIG. 6, the horizontal axis represents the dew point temperature difference ΔTdp, and the vertical axis represents the evaporation temperature. In the refrigerant circuit 21 of the air conditioning system 100, the dew point temperature Tdp [° C.] of the indoor air RA detected by the temperature / humidity detection unit 32 of FIG. 3 and the dew point temperature Tdp of the target air set by the setting input unit 44. The target evaporation temperature Te [° C.] is determined according to the dew point temperature difference ΔTdp (latent heat load) that is the difference from [° C.].

  As shown in FIG. 6, the target evaporation temperature Te is determined within an evaporation temperature range determined between the maximum evaporation temperature Te_max [° C.] and the minimum evaporation temperature Te_min [° C.].

  The target evaporation temperature Te is set to be smaller as the dew point temperature difference ΔTdp is larger in the range of 0 to Tdp1. For example, as shown in FIG. 6, when the dew point temperature difference ΔTdp is zero, the target evaporation temperature Te is set to the maximum evaporation temperature Te_max. When the dew point temperature difference ΔTdp is the allowable dew point temperature difference Tdp1, the target evaporation temperature Te is set to the minimum evaporation temperature Te_min. The relationship between the dew point temperature difference ΔTdp and the target evaporation temperature Te may be a linear relationship (straightness) as shown in FIG. 6, or may be determined by a function that decreases the tilt angle as the dew point temperature difference ΔTdp decreases. Well, it can be set arbitrarily.

  The centralized controller 102 transmits information on the determined target evaporation temperature Te to the control unit 51, and the control unit 51 controls the refrigerant circuit (the frequency of the compressor 22) of the refrigerant circuit 21 so that the target evaporation temperature Te is reached. Control, rotation speed control of the blower 27, etc.).

  The air conditioning system according to the present embodiment optimizes the heat treatment distribution between the internal air conditioner (air conditioner) and the external air conditioner (ventilator) by determining the evaporation temperature Te as described above. The external air conditioner processes latent heat and the internal air conditioner operates to process sensible heat. In order to operate in such a manner, the centralized controller 102 sets the evaporating temperature Te of the external air conditioner to an absolute humidity difference ΔX (FIG. 5) or a dew point temperature difference ΔTdp (FIG. 6) within a range that does not cause excessive heat treatment (Te_min to Te_max). ).

  As shown in FIG. 5 or FIG. 6, in order to determine the target evaporation temperature Te, it is necessary to change the range (Te_min to Te_max) in which excessive heat treatment is not performed according to the situation. The determination process of the target evaporation temperature Te including the change of the range will be described using a flowchart.

  FIG. 7 is a flowchart showing the operation of the air conditioning system according to Embodiment 1 of the present invention. The process of the flowchart of FIG. 7 is called from the main routine and executed when a driving instruction is issued, or every predetermined time or every predetermined condition is satisfied. Hereinafter, the operation of the centralized controller 102 will be described with reference to FIG.

  The centralized controller 102 starts the operation of the refrigerant circuit 21 and starts a timer. The centralized controller 102 acquires the temperature and absolute humidity of the indoor air RA and the temperature and absolute humidity of the outdoor air OA from the detection values of the temperature / humidity detection unit 31 and the temperature / humidity detection unit 32 (step S1).

  Next, the centralized controller 102 determines whether or not the ventilation device 3 of the refrigerant circuit 21 uses the total heat exchanger 30 (step S2). Whether or not the ventilation device 3 uses the total heat exchanger 30 can be determined, for example, by whether or not the centralized controller 102 itself has switched to a bypass air path that bypasses the total heat exchanger 30.

  When the ventilator 3 uses the total heat exchanger 30 (YES in S2), the absolute humidity exchange efficiency ηhx of the total heat exchanger 30, the absolute humidity x_ra of the indoor air RA, and the absolute humidity x_oa of the outdoor air OA Then, the absolute humidity x_0 of the intake air IA is calculated, and the absolute humidity x_0 is converted into a dew point temperature to determine the dew point temperature Tdp_0 of the intake air IA (step S3).

  On the other hand, for example, when the ventilator 3 does not use the total heat exchanger 30 due to a bypass air passage or the like, or when the ventilator 3 does not include the total heat exchanger 30 (NO in S2), concentration is performed. The controller 102 converts the absolute humidity of the outdoor air OA into a dew point temperature, obtains the dew point temperature of the outdoor air OA, and sets this as the dew point temperature Tdp_0 of the intake air IA (step S4).

  Then, the maximum evaporation temperature Te_max is determined based on the relationship among the dew point temperature Tdp_0 of the intake air IA, the dew point temperature Tdp_in of the indoor air RA at the target absolute humidity, and the temperature efficiency ηt of the cooler 26 (step S5). Then, the centralized controller 102 determines the minimum evaporation temperature Te_min in step S6.

  Hereinafter, a method for determining the maximum evaporation temperature Te_max and the minimum evaporation temperature Te_min will be described in order.

(Determination of maximum evaporation temperature Te_max)
FIG. 8 is an air diagram showing changes in the air state in the supply air passage A of the ventilator of FIG. The vertical axis of the air diagram of FIG. 8 is the absolute humidity [kg / kg ′] of the air, and the horizontal axis is the dry bulb temperature [° C.] of the air.

  The air state is represented by one point on the air diagram from the dry bulb temperature and the absolute humidity, and FIG. 8 shows the air states of the outdoor air OA, the intake air IA, and the supply air SA. . Here, the case where the outdoor air OA is hotter and humid than the indoor air RA will be described as an example.

  Referring to FIGS. 3 and 8, outdoor air OA undergoes total heat exchange with indoor air RA from exhaust ventilation path B when passing through total heat exchanger 30 and is cooled and dehumidified to become intake air IA. 26 flows in.

  The intake air IA that has flowed into the cooler 26 is cooled to a dew point temperature Tdp_0 or lower when passing through the cooler 26, is cooled and dehumidified, and is supplied to the room 200 as supply air SA.

  In this way, in the air supply ventilation path A, the outdoor air OA is cooled and dehumidified by total heat exchange with the indoor air RA in the total heat exchanger 30, and further cooled and dehumidified by the cooler 26 before being supplied to the room 200. The

  On the air diagram of FIG. 8, if the dew point temperature Tdp_sa of the supply air SA is equal to or lower than the dew point temperature Tdp_in of the target room air, the latent heat load of the room 200 is processed and the room 200 is moved to the target absolute humidity ( Or the target dew point temperature) or lower can be achieved. In other words, the indoor humidity can be gradually lowered to the target value by ventilating the supply air SA with the room air. In other words, in order to process the latent heat load in the room 200 and set the room 200 to the target absolute humidity (or target dew point temperature), the dew point temperature Tdp_sa of the supply air SA only needs to match the target dew point temperature Tdp_in.

  Moreover, what is necessary is just to adjust the evaporation temperature of the cooler 26 in order to adjust the absolute humidity (dew point temperature) of supply air SA. If the evaporation temperature of the cooler 26 increases, the absolute humidity (dew point temperature) of the supply air SA increases. Therefore, the latent heat treatment capability of the cooler 26 decreases, and if the evaporation temperature of the cooler 26 decreases, the absolute value of the supply air SA increases. Since the humidity decreases, the latent heat treatment capability of the cooler 26 increases.

  From the above, in order to process the latent heat load of the room 200 and set the room 200 to the target absolute humidity (or target dew point temperature), the dew point temperature Tdp_sa of the supply air SA is determined as the dew point temperature of the room air RA at the target absolute humidity. The evaporation temperature when it coincides with (or the target dew point temperature) Tdp_in may be set as the maximum value of the evaporation temperature of the cooler 26 (hereinafter referred to as the maximum evaporation temperature Te_max).

  That is, if the target evaporation temperature Te is set within a predetermined range below the maximum evaporation temperature Te_max, the latent heat treatment of the cooler 26 does not become excessive, and energy consumption can be reduced while maintaining comfort.

  Specifically, the relationship between the dew point temperature Tdp_0 of the intake air IA flowing into the cooler 26, the dew point temperature (or target dew point temperature) Tdp_in of the indoor air RA at the target absolute humidity, and the temperature efficiency ηt of the cooler 26 Based on this, the maximum evaporation temperature Te_max is determined.

Here, the temperature efficiency ηt of the cooler 26 is defined as the following formula (1).
Temperature efficiency ηt = (air temperature difference before and after passing through cooler 26) / (temperature of suction air IA−evaporation temperature) (1)
An air temperature difference before and after passing through the cooler 26 is defined as (Tdp_0−Tdp_in), and (temperature of the intake air IA−evaporation temperature) is defined as (Tdp_0−Te_max). Then, the following formula (2) is obtained.

(Tdp_0−Te_max): (Tdp_0−Tdp_in) = 1: ηt (2)
If the maximum evaporation temperature Te_max is determined so as to satisfy the above equation (2), the dew point temperature Tdp_sa of the supply air SA matches the dew point temperature (or target dew point temperature) Tdp_in of the indoor air RA at the target absolute humidity.

  The temperature efficiency ηt is a fixed value set in advance according to the refrigeration capacity of the refrigerant circuit 21, the heat exchange capacity of the cooler 26, and the like.

  That is, the control device 101 determines the dew point temperature Tdp_0 of the intake air IA based on the absolute humidity x_0 of the intake air IA flowing into the cooler 26. Then, the control device 101 compares the difference between the dew point temperature Tdp_0 of the intake air IA and the target dew point temperature Tdp_in, and the difference between the dew point temperature Tdp_0 of the intake air IA and the maximum evaporation temperature Te_max that is the evaporation temperature that matches the target dew point temperature Tdp_in. The maximum evaporating temperature Te_max is determined so that the ratio to the temperature efficiency ηt of the cooler 26 matches. Since the target evaporation temperature Te is set lower than the maximum evaporation temperature Te_max as shown in FIGS. 5 and 6, the control device 101 sets the refrigerant pressure when the dew point temperature of the supply air SA exceeds the maximum evaporation temperature Te_max. The compressor and the like are controlled so as to decrease. The control device 101 controls the frequency of the compressor 22 so as to reduce the refrigerant pressure. In order to reduce the refrigerant pressure, instead of or in addition to the frequency control of the compressor 22, the rotational speed control of the blower 27, the opening degree change control of the expansion valve 25, and the like may be performed.

  Further, the dew point temperature Tdp_0 of the intake air IA flowing into the cooler 26 can be converted from the absolute humidity x_0 of the intake air IA flowing into the cooler 26.

  The absolute humidity x_0 of the intake air IA can be obtained from the absolute humidity exchange efficiency ηhx of the total heat exchanger 30, the absolute humidity x_ra of the indoor air RA, and the absolute humidity x_oa of the outdoor air OA.

  Here, the absolute humidity exchange efficiency ηhx of the total heat exchanger 30 is a value unique to the total heat exchanger 30 and is a preset value. The absolute humidity x_ra of the indoor air RA is detected by the temperature / humidity detector 32. The absolute humidity x_oa of the outdoor air OA is detected by the temperature / humidity detection unit 31.

  The absolute humidity exchange efficiency ηhx may vary depending on the air conditions for total heat exchange, and therefore may be changed according to the indoor 200 and outdoor air conditions.

  In the above description, the case where the absolute humidity x_0 and the dew point temperature Tdp_0 of the intake air IA flowing into the cooler 26 is calculated from the absolute humidity exchange efficiency ηhx, the absolute humidity x_ra, the absolute humidity x_oa, and the like has been described. The invention is not limited to this. A sensor for detecting the dew point temperature Tdp_0 of the intake air IA flowing into the cooler 26 may be provided separately.

  The method for determining the maximum evaporation temperature Te_max has been described above. Returning to FIG. 7 again, the centralized controller 102 determines the minimum evaporation temperature Te_min in step S6. Below, the detail of the determination method of minimum evaporation temperature Te_min is demonstrated.

(Determination of minimum evaporation temperature Te_min)
The minimum evaporation temperature Te_min is set to a value obtained by subtracting the drop α from the maximum evaporation temperature Te_max.

  The decrease α may be a preset fixed value (for example, 5K) or may be determined according to the latent heat load in the room 200.

  For example, when determining according to the latent heat load in the room 200, the drop α can be determined from the evaporation temperature at which the latent heat load can be processed when the number of seated persons in the room 200 is maximum.

  The generated latent heat load Ltp from the room 200 is determined by the following equation (3) from the maximum number of people Np_max [person] and the preset latent heat load Lp [kW / person] per person.

Ltp = Np_max × Lp [kW] (3)
Then, the amount of decrease in the evaporation temperature from the maximum evaporation temperature Te_max for processing the generated latent heat load Ltp is calculated with the ventilation air volume V of the air supply blower 28 of the ventilation device 3, and the calculated amount of decrease is calculated as the amount of decrease α. And As described above, α is obtained, and Te_max−α is set to the minimum evaporation temperature Te_min. Since the target evaporation temperature Te is set higher than the minimum evaporation temperature Te_min as shown in FIGS. 5 and 6, the control device 101 reduces the refrigerant pressure when the dew point temperature of the supply air SA falls below the minimum evaporation temperature Te_min. Control the compressor etc. to raise. The control device 101 controls the frequency of the compressor 22 so as to increase the refrigerant pressure. In order to reduce the refrigerant pressure, instead of or in addition to the frequency control of the compressor 22, the rotational speed control of the blower 27, the opening degree change control of the expansion valve 25, and the like may be performed.

  Here, in order to create a map for converting the humidity difference ΔX illustrated in FIG. 5 into the target evaporation temperature Te, it is necessary to further determine the allowable humidity difference X1 in addition to Te_max and Te_min. A method for determining the allowable humidity difference X1 will also be described.

(Determination of allowable humidity difference X1)
The allowable humidity difference X1 is a humidity difference that is allowed for comfort. For example, if the target room temperature / target relative humidity = 26 ° C./50% (absolute humidity x), the actual room temperature / actual relative humidity = 26 ° C./55% (absolute humidity x ′) can be allowed. , X1 = x′−x. This allowable humidity difference X1 may be a fixed value set in advance or may be changed according to the target indoor temperature.

  As shown in FIG. 5, when the humidity difference ΔX falls below the allowable humidity difference X1, the target evaporation temperature Te rises. That is, the amount of latent heat treatment can be reduced and the energy consumption can be reduced by raising the target evaporation temperature Te within a range that does not impair the comfort of the room 200.

  In addition, it has been explained that FIG. 6 may be used instead of FIG. 5, but in order to create a map for converting the humidity difference ΔTdp of FIG. 6 into the target evaporation temperature Te, in addition to Te_max and Te_min, further allowance It is necessary to determine the humidity difference Tdp1. A method for determining the allowable humidity difference Tdp1 will also be described.

(Determination of allowable dew point temperature difference Tdp1)
The allowable humidity difference Tdp1 is a dew point temperature difference that is allowed for comfort. For example, if target room temperature / target relative humidity = 26 ° C./50% (dew point temperature Tdp), actual room temperature / actual relative humidity = 26 ° C./55% (absolute humidity Tdp ′) can be allowed. , Tdp1 = tdp′−tdp. This allowable humidity difference Tdp1 may be a fixed value set in advance or may be changed according to the target indoor temperature.

  As shown in FIG. 6, when the humidity difference ΔTdp falls below the allowable humidity difference Tdp1, the target evaporation temperature Te increases. That is, within the range that does not impair the comfort of the room 200, the target evaporation temperature Te can be raised to reduce the amount of latent heat treatment, thereby reducing energy consumption.

  From the above, since the diagram shown in FIG. 5 or FIG. 6 can be created, preparation for determining the target evaporation temperature Te is complete.

  Returning again to FIG. 7, after Te_max and Te_min are determined in steps S5 and S6, the target evaporation temperature Te is determined in step S7.

  As shown in FIG. 5, the centralized controller 102 determines the absolute humidity x_ra of the indoor air RA and the absolute humidity Xa_tgt of the target air within the evaporation temperature range determined between the maximum evaporation temperature Te_max and the minimum evaporation temperature Te_min. The target evaporation temperature Te is determined according to the humidity difference ΔX.

  Alternatively, instead of the absolute humidity difference ΔX, as shown in FIG. 6, the dew point temperature Tdpa of the indoor air RA and the target air are within the evaporation temperature range determined between the maximum evaporation temperature Te_max and the minimum evaporation temperature Te_min. The target evaporation temperature Te may be determined according to the dew point temperature difference ΔTdp from the dew point temperature Tdp_tgt.

  In this way, in steps S5 to S7, the control device 101 sets the evaporation temperature range Te_max to Te_min, which is the range of the evaporation temperature, with the maximum evaporation temperature Te_max being the evaporation temperature that matches the target dew point temperature Tdp_in as the upper limit. . For example, as shown in FIG. 5, the control device 101 sets the target value Te of the evaporation temperature within the evaporation temperature range according to the difference ΔX between the absolute humidity x_ra of the room air RA and the target absolute humidity Xa_tgt of the room air RA. To decide. Further, for example, as shown in FIG. 6, the control device 101 sets the target value Te of the evaporation temperature within the evaporation temperature range according to the difference ΔTdp between the dew point temperature of the room air RA and the target dew point temperature of the room air RA. To decide. The control device 101 controls the evaporation temperature of the refrigerant circuit 21 so that the determined target value Te is obtained.

  Thereafter, the centralized controller 102 determines whether or not the target room temperature or the target room humidity has been changed by the setting input unit 44, or whether or not the timer has reached a certain time T1 (step S8). If the condition at step S8 is not satisfied, the centralized controller 102 repeatedly executes the operation at step S7.

  On the other hand, when the condition of step S8 is satisfied, the centralized controller 102 resets the timer (step S9), and returns the process to the main routine in step S10.

  As shown in the flowchart, in the present embodiment, Te_max, Te_min, and target evaporation temperature Te are periodically determined in order to cope with changes in the outside air and changes in the room air. In particular, since the humidity in the room does not change immediately even if the target evaporation temperature Te is reset, the target evaporation temperature Te is reset after looking at the situation (humidity) after operating for a certain time (here, T1). It is said.

  As described above, in the present embodiment, the evaporation temperature at which the dew point temperature Tdp_sa of the supply air SA matches the dew point temperature Tdp_in of the indoor air RA at the target absolute humidity is obtained as the maximum evaporation temperature Te_max, and the maximum evaporation temperature Te_max is determined. The evaporation temperature of the refrigerant circuit is controlled to be lower. For example, when the dew point temperature Tdp_sa of the supply air SA exceeds the target dew point temperature (= Tdp_in) of the indoor air, the control device 101 controls the frequency of the compressor 22 so as to reduce the refrigerant pressure. In order to reduce the refrigerant pressure, instead of or in addition to the frequency control of the compressor 22, the rotational speed control of the blower 27, the opening degree change control of the expansion valve 25, and the like may be performed.

  For this reason, it becomes possible to set it as the optimal evaporation temperature according to a latent heat load. That is, it is possible to reliably process the latent heat load, and to suppress an excessive amount of latent heat treatment, thereby suppressing a decrease in performance in terms of energy saving while maintaining comfort.

  Further, within the evaporation temperature range (Te_min to Te_max), the target evaporation temperature Te is determined according to the humidity difference ΔX (latent heat load) or the dew point temperature difference ΔTdp (latent heat load). For this reason, evaporation temperature can be made high in the range which does not impair comfort. This effect will be described with reference to FIG.

  FIG. 9 is a ph diagram of the second refrigerant system in the first embodiment of the present invention. As shown in FIG. 5 or FIG. 6, the refrigerant state at the inlet of the compressor 22 changes to the point XA as shown in FIG. 9 by increasing the target evaporation temperature Te as the humidity difference ΔX or dew point temperature difference ΔTdp decreases. To point XB.

  Accordingly, as can be seen from the ph diagram shown in FIG. 9, the difference between the high pressure and the low pressure is reduced by increasing the evaporation temperature, and the load applied to the compressor 22 is reduced. The compressor 22 input is reduced from H1 to H2, and the air conditioning system can be operated with high efficiency. Therefore, reduction of the power consumption of an air conditioning system is realizable.

(Modification 1)
Here, another example of the determination operation of the maximum evaporation temperature Te_max will be described.

  FIG. 10 is a flowchart showing Modification 1 of the operation of the air-conditioning system according to Embodiment 1 of the present invention. The flowchart of FIG. 10 includes processes of steps S13, S14, and S15 instead of steps S3, S4, and S5 in the flowchart of FIG. Hereinafter, differences from FIG. 7 described above will be described with reference to FIG.

  When the condition of step S2 is satisfied, the centralized controller 102 changes the temperature T0 of the intake air IA to the temperature t_ra of the indoor air RA, the temperature t_oa of the outdoor air OA, and the temperature exchange efficiency ηt2 of the total heat exchanger 30. Based on the determination (step S13). On the other hand, when the condition of step S2 is not satisfied, the centralized controller 102 sets the temperature t_oa of the outdoor air OA as the temperature T0 of the intake air IA (step S14).

  Then, the maximum evaporation temperature Te_max is determined using the temperature T0 of the intake air IA obtained in step S13 or step S14 (step S15). Other operations are the same as those in FIG.

  Here, the processing in step S13 and step S15 will be described in more detail.

  FIG. 11 is an air diagram showing changes in the air state in the supply air passage A of the ventilator of FIG.

  In FIG. 11, assuming that the relative humidity of the supply air SA is 100%, the dry bulb temperature T0 of the intake air IA flowing into the cooler 26, the dew point temperature Tdp_in of the target indoor air, and the temperature efficiency ηt of the cooler 26 From this, the maximum evaporation temperature Te_max is determined (step S15).

  That is, if the maximum evaporation temperature Te_max is determined so as to satisfy the following equation (4), the dew point temperature Tdp_sa of the supply air SA matches the dew point temperature Tdp_in of the indoor air RA at the target absolute humidity.

(T0−Te_max): (T0−Tdp_in) = 1: ηt (4)
The temperature T0 of the intake air IA can be determined based on the temperature t_ra of the indoor air RA, the temperature t_oa of the outdoor air OA, and the temperature exchange efficiency ηt2 of the total heat exchanger 30 (step S13).

  Here, the temperature exchange efficiency ηt2 of the total heat exchanger 30 is a value unique to the total heat exchanger 30, and is set in advance. The temperature t_ra of the indoor air RA is obtained from the temperature / humidity detection unit 32. The temperature t_oa of the outdoor air OA is obtained from the temperature / humidity detection unit 31.

  Note that the temperature exchange efficiency ηt2 may vary depending on the air conditions for total heat exchange, and therefore may be changed according to the indoor 200 and outdoor air conditions.

  In the above description, the case where the temperature T0 of the intake air IA flowing into the cooler 26 is calculated has been described, but the present invention is not limited to this. A sensor for detecting the temperature T0 of the intake air IA flowing into the cooler 26 may be separately provided.

  Note that the determination method of the minimum evaporation temperature Te_min, the determination method of the allowable humidity difference X1, and the determination method of the allowable dew point temperature difference Tdp1 are the same as the processing after the determination of Te_max in the first embodiment.

Even in such an operation, the same effect as in the first embodiment can be obtained.
(Modification 2)
In the above-described operation, the case where the temperature efficiency ηt of the cooler 26 is set in advance has been described, but the present invention is not limited to this. You may make it change the temperature efficiency (eta) t of the cooler 26 according to an operating condition.

FIG. 12 is a diagram showing the relationship between the temperature efficiency ηt of the cooler 26 and the temperature difference ΔT.
As shown in FIG. 12, there is a relationship that the temperature efficiency ηt of the cooler 26 increases as the temperature difference ΔT between the temperature of the intake air IA and the evaporation temperature of the cooler 26 increases.

  For this reason, the centralized controller 102 stores information (table) on the relationship between the temperature difference ΔT and the temperature efficiency ηt, and calculates the temperature difference ΔT between the temperature of the intake air IA and the evaporation temperature of the cooler 26. The temperature efficiency ηt may be determined by detection.

FIG. 13 is a diagram illustrating the relationship between the temperature efficiency ηt of the cooler 26 and the air volume of the supply air passage A.
As shown in FIG. 13, there is a relationship that the temperature efficiency ηt of the cooler 26 decreases as the air volume in the air supply ventilation path A (the air volume of the exhaust fan 29) increases.

  For this reason, the centralized controller 102 stores information (table) on the relationship between the air volume of the air supply path A and the temperature efficiency ηt, and the air volume of the air supply path A (the flow of the exhaust fan 29). The air efficiency) may be detected to determine the temperature efficiency ηt.

  FIG. 14 is a diagram showing the relationship between the temperature efficiency ηt of the cooler 26 and the degree of superheat SH at the outlet of the cooler 26.

  As shown in FIG. 14, there is a relationship in which the temperature efficiency ηt of the cooler 26 decreases as the degree of superheat SH at the outlet of the cooler 26 increases.

  For this reason, the centralized controller 102 stores information (table) on the relationship between the superheat degree SH at the outlet of the cooler 26 and the temperature efficiency ηt, detects the superheat degree SH at the outlet of the cooler 26, The temperature efficiency ηt may be determined.

Thus, the maximum evaporating temperature Te_max can be determined with higher accuracy by determining the temperature efficiency ηt of the cooler 26 according to the operating conditions and the like.
(Modification 3)
In the above description, the operation of adjusting the evaporation temperature of the refrigerant circuit 21 has been described. However, the operation of adjusting the evaporation temperature of the refrigerant circuit 11 that mainly processes the sensible heat load may be performed simultaneously. Specific examples will be described below.

  FIG. 15 is a diagram for explaining the operation of Modification 3 of the air-conditioning system according to Embodiment 1 of the present invention. In FIG. 15, the horizontal axis indicates the temperature difference ΔT, and the vertical axis indicates the evaporation temperature of the refrigerant circuit 11.

  As shown in FIG. 15, in the refrigerant circuit 11 of the air conditioning system 100, the indoor air temperature Ta [° C.] detected by the temperature / humidity detection units 43 A and 43 B and the target air set by the setting input unit 44. The target evaporation temperature Te1 [° C.] is determined in accordance with the temperature difference ΔT (sensible heat load) from the temperature Ta_tgt [° C.]. The refrigerant circuit 11 corresponds to the “second refrigerant circuit” in the present invention.

  The target evaporation temperature Te1 is determined within an evaporation temperature range determined between the maximum evaporation temperature Te_max1 [° C.] and the minimum evaporation temperature Te_min1 [° C.].

Further, the target evaporation temperature Te1 is set to be smaller as the temperature difference ΔT is larger.
For example, as shown in FIG. 15, when the temperature difference ΔT is zero, the target evaporation temperature Te1 is set to the maximum evaporation temperature Te_max1, and when the temperature difference ΔT is the allowable temperature T1, the target evaporation temperature Te1 is set to the minimum evaporation temperature Te_min1. To do. Note that the relationship between the temperature difference ΔT and the target evaporation temperature Te1 may be a proportional relationship (straight line) as shown in FIG. Can be set.

  Referring to FIGS. 4 and 15, the air conditioning system further includes an air conditioning apparatus that processes indoor sensible heat load, in addition to ventilation apparatus 3 that performs ventilation. The air conditioner includes indoor heat exchangers 16A and 16B, a compressor 12, an outdoor heat exchanger 14 that operates as a condenser, and a refrigerant circuit 21 that circulates refrigerant through expansion valves 15A and 15B. The control device 101 controls the evaporation temperature of the refrigerant circuit 21 according to the difference ΔT between the temperature of the room air RA and the target temperature of the room air RA.

  The centralized controller 102 transmits information of the determined target evaporation temperature Te1 to the control unit 41, and the control unit 41 controls the refrigerant circuit of the refrigerant circuit 11 (the frequency of the compressor 12) so that the target evaporation temperature Te1 is reached. Control, rotation speed control of the fans 17, 18A, 18B, etc.).

  The maximum evaporation temperature Te_max1 and the minimum evaporation temperature Te_min1 may be fixed values set in advance, or may be changed according to the load of the air conditioning harmony system.

  For example, when the load is large, the maximum evaporation temperature Te_max1 and the minimum evaporation temperature Te_min1 are set low.

  On the other hand, when the load is small, the maximum evaporation temperature Te_max1 and the minimum evaporation temperature Te_min1 are set high.

  Here, as a method for determining the load, the temperature of the outdoor air OA may be used, or other load detection means may be used.

  As described above, the sensible heat treatment is controlled by the refrigerant circuit 11 that is the indoor unit system, and the latent heat treatment is independently controlled by the refrigerant circuit 21 that is the ventilator system. It becomes easy to set both the target humidity and the target value.

  The embodiment disclosed this time should be considered as illustrative in all points and not restrictive. The scope of the present invention is shown not by the above description of the embodiments but by the scope of claims, and is intended to include all modifications within the meaning and scope equivalent to the scope of claims.

1A, 1B, 1C Indoor unit, 2, 4 Outdoor unit, 3 Ventilator, 11, 21 Refrigerant circuit, 12, 22 Compressor, 13, 23 Four-way valve, 14, 24 Outdoor heat exchanger, 15, 15A, 15B, 25 Expansion valve, 16A, 16B Indoor heat exchanger, 17, 18A, 18B, 27 Blower, 26 Cooler, 28 Blower for air supply, 29 Blower for exhaust, 30 Total heat exchanger, 31, 32, 43A, 43B Temperature・ Humidity detection unit, 33 detection unit, 41, 51 control unit, 42, 52 temperature detection unit, 44 setting input unit, 100 air conditioning system, 101 control device, 102 centralized controller, 103 transmission line, 104, 105 refrigerant piping, 200
Indoor, A air supply ventilation path, B exhaust ventilation path.

Claims (12)

A first heat exchanger configured to function as an evaporator;
A refrigerant circuit configured to circulate refrigerant through a compressor, a condenser, an expansion valve and the first heat exchanger;
A ventilator configured to supply air taken from outside and heat-exchanged with the refrigerant by the first heat exchanger into a room;
A detection unit provided at an indoor outlet of the ventilator and configured to detect a dew point temperature of supply air from the indoor outlet;
An air conditioner comprising: a control device configured to reduce the pressure of the refrigerant when a dew point temperature of the supply air detected by the detection unit exceeds a preset target dew point temperature of indoor air. system.   The air conditioning system according to claim 1, wherein the control device sets a dew point temperature at a target absolute humidity of the room air as the target dew point temperature. The control device has an evaporation temperature that matches the target dew point temperature based on the absolute humidity of the intake air flowing into the first heat exchanger, the target dew point temperature, and the temperature efficiency of the first heat exchanger. Find the maximum evaporation temperature
The air conditioning system according to claim 1 or 2, wherein the control device decreases the pressure of the refrigerant when a dew point temperature of the supply air exceeds the maximum evaporation temperature. The control device is configured to increase the pressure of the refrigerant when a dew point temperature of the supply air detected by the detection unit falls below a minimum evaporation temperature,
The air conditioning system according to claim 3, wherein the minimum evaporation temperature is a temperature lower than the maximum evaporation temperature by a predetermined value. The control device obtains the dew point temperature of the intake air based on the absolute humidity of the intake air flowing into the first heat exchanger,
The control device has a ratio between a difference between the dew point temperature of the intake air and the target dew point temperature, and a difference between a dew point temperature of the intake air and a maximum evaporation temperature that is an evaporation temperature that matches the target dew point temperature, The air conditioning system according to claim 1 or 2, wherein the maximum evaporation temperature is determined so as to coincide with a temperature efficiency of the first heat exchanger. The ventilator is
An air supply passage for supplying outdoor air into the room;
An exhaust ventilation path for exhausting the indoor air to the outside;
A total heat exchanger that performs total heat exchange between the outdoor air flowing through the air supply ventilation path and the indoor air flowing through the exhaust ventilation path,
The first heat exchanger is disposed downstream of the total heat exchanger in the supply air passage.
The control device determines the absolute humidity of the intake air based on the absolute humidity of the indoor air, the absolute humidity of the outdoor air, and the absolute humidity exchange efficiency of the total heat exchanger. 4. The air conditioning system according to 4.   The control device has an evaporation temperature that matches the target dew point temperature based on the temperature of the intake air flowing into the first heat exchanger, the target dew point temperature, and the temperature efficiency of the first heat exchanger. The air conditioning system according to claim 1 or 2, wherein a certain maximum evaporation temperature is determined.   The control device is configured such that a ratio between the difference between the temperature of the intake air and the target dew point temperature and the difference between the temperature of the intake air and the maximum evaporation temperature matches the temperature efficiency of the first heat exchanger. The air conditioning system according to claim 7, wherein the maximum evaporation temperature is determined. The ventilator is
An air supply passage for supplying outdoor air into the room;
An exhaust ventilation path for exhausting the indoor air to the outside;
A total heat exchanger that performs total heat exchange between the outdoor air flowing through the air supply ventilation path and the indoor air flowing through the exhaust ventilation path,
The first heat exchanger is disposed downstream of the total heat exchanger in the supply air passage.
The air conditioning according to claim 7 or 8, wherein the control device determines a temperature of the intake air based on a temperature of the indoor air, a temperature of the outdoor air, and a temperature exchange efficiency of the total heat exchanger. system. The control device sets an evaporation temperature range that is a range of the evaporation temperature, with a maximum evaporation temperature that is an evaporation temperature that matches the target dew point temperature as an upper limit,
The control device determines a target value of the evaporation temperature within the evaporation temperature range according to a difference between an absolute humidity of the room air and a target absolute humidity of the room air,
The air conditioning system according to any one of claims 2 to 9, wherein the control device controls an evaporation temperature of the refrigerant circuit so as to be the determined target value. An air conditioner for processing the sensible heat load in the room;
The air conditioner is
A second heat exchanger;
A second compressor, a second condenser, a second expansion valve, and a second refrigerant circuit for circulating refrigerant through the second heat exchanger,
The air according to any one of claims 1 to 10, wherein the control device controls an evaporation temperature of the second refrigerant circuit according to a difference between a temperature of the room air and a target temperature of the room air. Harmony system. A first heat exchanger configured to function as an evaporator, a compressor, a condenser, an expansion valve, a refrigerant circuit configured to circulate refrigerant through the first heat exchanger, and an external intake A ventilator configured to supply the air heat-exchanged with the refrigerant by the first heat exchanger into a room; and a supply from the indoor side air outlet provided in the indoor air outlet of the ventilator. A control method for an air conditioning system having a detector configured to detect a dew point temperature of air,
Calculating a dew point temperature of the supply air from a detection result of the detection unit;
And a step of reducing the pressure of the refrigerant when the dew point temperature of the supply air exceeds a preset target dew point temperature of the indoor air.

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