JPWO2019193639A1 - Air conditioning system - Google Patents

Abstract

A first refrigerant circuit including a first compressor, a first outdoor heat exchanger, and a first indoor heat exchanger, a second compressor, a second outdoor heat exchanger, a second indoor heat exchanger, and a third indoor heat. A second refrigerant circuit equipped with a exchanger, an indoor unit equipped with a second indoor heat exchanger to control the temperature of indoor air, and an indoor unit equipped with a first indoor heat exchanger and a third indoor heat exchanger, and taken in outdoor air. It is an air conditioning system equipped with an outside air supply unit that regulates the humidity of the air.

Description

The present invention relates to an air conditioning system, and more particularly to an air conditioning system including an external air conditioner.

Conventionally, in an air conditioning system installed in a building or the like, indoor ventilation is performed by exchanging indoor air and outdoor air. At this time, if the outdoor air is introduced into the room as it is, the air conditioning load in the room increases. For example, if the outside air with high humidity is introduced as it is in summer, the humidity in the room rises and the latent heat load in the room increases. In order to prevent such an increase in the latent heat load, it is known that the temperature and humidity of the outdoor air taken in is adjusted by an external air conditioner. For example, in the air conditioning system described in Patent Document 1, it has been proposed to reduce the humidity of the introduced air by an outside air supply unit including an evaporator of an external air conditioner.

Japanese Unexamined Patent Publication No. 2005-049059

When dehumidifying the outdoor air with the evaporator of the external air conditioner as in the air conditioning system of Patent Document 1, it is necessary to operate at a low evaporation temperature of the refrigerant flowing through the external air conditioner in order to reduce the air conditioning load. There is. In this case, although the amount of dehumidification increases as the evaporation temperature is lowered, there is a problem that the compression ratio of the compressor in the external air conditioner becomes high and the power consumption increases.

The present invention has been made to solve the above problems, and an object of the present invention is to provide an air conditioning system capable of reducing an indoor air conditioning load without increasing power consumption.

The air conditioning system according to the present invention includes a first refrigerant circuit including a first compressor, a first outdoor heat exchanger, and a first indoor heat exchanger, a second compressor, a second outdoor heat exchanger, and a second. A second refrigerant circuit equipped with an indoor heat exchanger and a third indoor heat exchanger, an indoor unit equipped with a second indoor heat exchanger to control the temperature of indoor air, a first indoor heat exchanger and a third indoor heat exchanger. It is equipped with a exchanger and an outside air supply unit that regulates the humidity of the outdoor air taken in.

According to the present invention, the outside air supply unit is provided with a first indoor heat exchanger and a third indoor heat exchanger to dehumidify the outdoor air in two stages by two heat exchangers constituting different refrigerant circuits. Can be cooled. As a result, the evaporation temperature of the first room heat exchanger can be raised as compared with the case of dehumidifying and cooling the first room heat exchanger alone, and the air conditioning load can be reduced while suppressing the increase in the power consumption of the air conditioning system. It can be reduced.

It is a schematic block diagram of the air conditioning system in Embodiment 1. FIG. It is a schematic block diagram of the 1st refrigerant circuit in Embodiment 1. FIG. It is a schematic block diagram of the 2nd refrigerant circuit in Embodiment 1. FIG. It is a schematic block diagram of the outside air supply unit in Embodiment 1. FIG. It is an air diagram which shows the change of the air temperature and humidity of the outside air supply unit at the time of a cooling dehumidification operation. It is a functional block diagram of the control device in Embodiment 1. FIG. It is a figure explaining the method of determining the 1st evaporation temperature in Embodiment 1. FIG. It is a figure explaining the method of determining the 2nd evaporation temperature in Embodiment 1. FIG. It is a flowchart which shows the evaporation temperature determination process in Embodiment 1. It is a flowchart which shows the operation control processing in Embodiment 1. It is a schematic block diagram of the air conditioning system in Embodiment 2. It is a functional block diagram of the control device in Embodiment 2. FIG. It is a flowchart which shows the evaporation temperature determination process in Embodiment 2. It is a flowchart which shows the operation control processing in Embodiment 2.

Embodiment 1.
FIG. 1 is a schematic configuration diagram of the air conditioning system 50 according to the first embodiment. The air conditioning system 50 includes an external air conditioner 1 that takes in outdoor air and adjusts the temperature and humidity to blow it out to the indoor R, and an internal air conditioner 2 that takes in indoor air and at least adjusts the temperature and blows it out to the indoor R. .. The external air conditioner 1 includes an external air conditioner outdoor unit 10 arranged on the roof or underground, and an outside air supply unit 30 arranged on the ceiling C of the room R or under the floor. The internal adjustment machine 2 includes an internal adjustment outdoor unit 20 arranged on the roof or underground, and an indoor unit 21 arranged on the ceiling or floor of the indoor R. In the present embodiment, the internal adjustment machine 2 includes two indoor units 21, but the number of indoor units 21 may be one or three or more.

Further, the air conditioning system 50 includes a control device 5, an indoor temperature sensor 201 that detects the indoor temperature Ta of the indoor R, an indoor humidity sensor 301 that detects the indoor humidity Xa of the indoor R, and an outside air that detects the outside air temperature Toa. It includes a temperature sensor 303. The room temperature Ta, the room humidity Xa, and the outside air temperature Toa detected by the room temperature sensor 201, the room humidity sensor 301, and the outside air temperature sensor 303 are transmitted to the control device 5. The control device 5 is, for example, a centralized controller, and controls the operation of the external air conditioner 1 and the internal air conditioner 2 based on the indoor temperature Ta, the indoor humidity Xa, the outside air temperature Toa, and the like. The control by the control device 5 will be described in detail later.

The air conditioning system 50 includes a first refrigerant circuit 100 having an external air conditioning outdoor unit 10 on the heat source side, and a second refrigerant circuit 200 having an internal air conditioning outdoor unit 20 on the heat source side. FIG. 2 is a schematic configuration diagram of the first refrigerant circuit 100 according to the first embodiment. As shown in FIG. 2, the first refrigerant circuit 100 includes an external adjustment outdoor unit 10 and an external adjustment portion 30a of the outside air supply unit 30. The outdoor unit 10 includes a first compressor 13, a first four-way valve 14, a first outdoor heat exchanger 15, and a first outdoor fan 16. The external adjustment unit 30a of the outside air supply unit 30 includes a first expansion device 17, a first indoor heat exchanger 12, and a first evaporation temperature sensor 102. The external adjustment outdoor unit 10 and the external adjustment portion 30a are connected by a refrigerant pipe 40a.

The first compressor 13 is composed of, for example, an inverter compressor whose capacity can be controlled, sucks in a gas refrigerant, compresses it, and discharges it in a high temperature and high pressure state. The first four-way valve 14 switches the flow of the refrigerant in the first refrigerant circuit 100. The first outdoor heat exchanger 15 and the first indoor heat exchanger 12 are, for example, cross-fin type fin-and-tube heat exchangers composed of a heat transfer tube and a large number of fins. The first expansion device 17 is, for example, an electronic expansion valve whose opening degree can be controlled. The first outdoor fan 16 is a blower that supplies air to the first outdoor heat exchanger 15, and is, for example, a propeller fan driven by a fan motor (not shown). The operating frequency of the first compressor 13, the switching of the flow path of the first four-way valve 14, the opening degree of the first expansion device 17, and the air volume of the first outdoor fan 16 are controlled by the control device 5.

When the air conditioning system 50 performs the cooling / dehumidifying operation, the first four-way valve 14 is switched to the flow path shown by the solid line in FIG. Then, the low-temperature and low-pressure gas-state refrigerant is compressed by the first compressor 13 and discharged as a high-temperature and high-pressure gas refrigerant. The high-temperature and high-pressure gas refrigerant discharged from the first compressor 13 flows into the first outdoor heat exchanger 15 via the first four-way valve 14. The first outdoor heat exchanger 15 functions as a condenser, and the high-temperature and high-pressure refrigerant flowing into the first outdoor heat exchanger 15 dissipates heat to the outdoor air and the like, and is condensed into a high-pressure liquid refrigerant. The high-pressure liquid refrigerant flowing out of the first outdoor heat exchanger 15 flows into the first expansion device 17, is expanded and depressurized, and becomes a low-temperature low-pressure gas-liquid two-phase refrigerant. The gas-liquid two-phase refrigerant flowing out of the first expansion device 17 flows into the first chamber heat exchanger 12. The first chamber heat exchanger 12 functions as an evaporator, and the gas-liquid two-phase refrigerant flowing into the first chamber heat exchanger 12 exchanges heat with the air flowing in the outside air supply unit 30 and evaporates, resulting in low temperature and low pressure. It becomes a gas refrigerant. The gas refrigerant flowing out of the first chamber heat exchanger 12 is sucked into the first compressor 13 and compressed again. As a result, the air flowing through the outside air supply unit 30 is dehumidified by the first chamber heat exchanger 12.

FIG. 3 is a schematic configuration diagram of the second refrigerant circuit 200 according to the first embodiment. As shown in FIG. 3, the second refrigerant circuit 200 includes an internal adjustment outdoor unit 20, a plurality of indoor units 21, and an internal adjustment portion 30b of the outside air supply unit 30. The internal adjustment outdoor unit 20 includes a second compressor 23, a second four-way valve 24, a second outdoor heat exchanger 25, and a second outdoor fan 26. Further, each of the plurality of indoor units 21 includes a second indoor heat exchanger 22, a second expansion device 27, a second indoor fan 28, and a second evaporation temperature sensor 202, respectively. Further, the indoor temperature sensor 201 is provided at the suction portion of at least one of the plurality of indoor units 21. The internal adjustment unit 30b of the outside air supply unit 30 is connected in parallel with a plurality of indoor units 21, and includes a third indoor heat exchanger 32, a third expansion device 37, and a third evaporation temperature sensor 302. The internal adjustment outdoor unit 20, the indoor unit 21, and the internal adjustment portion 30b are connected by a refrigerant pipe 40b.

The second compressor 23 is composed of, for example, an inverter compressor whose capacity can be controlled, sucks gas refrigerant, compresses it, and discharges it in a high temperature and high pressure state. The second four-way valve 24 switches the flow of the refrigerant in the second refrigerant circuit 200. The second outdoor heat exchanger 25, the second indoor heat exchanger 22, and the third indoor heat exchanger 32 are, for example, a cross-fin type fin-and-tube type composed of a heat transfer tube and a large number of fins. It is a heat exchanger. The second expansion device 27 and the third expansion device 37 are, for example, electronic expansion valves whose opening degree can be controlled. The second outdoor fan 26 and the second indoor fan 28 are blowers that supply air to the second outdoor heat exchanger 25 and the second indoor heat exchanger 22, and are propellers driven by, for example, a fan motor (not shown). I'm a fan. The operating frequency of the second compressor 23, the switching of the flow path of the second four-way valve 24, the opening degree of the second expansion device 27 and the third expansion device 37, and the air volume of the second outdoor fan 26 and the second indoor fan 28 are , Controlled by the control device 5.

When the air conditioning system 50 performs the cooling / dehumidifying operation, the second four-way valve 24 is switched to the flow path shown by the solid line in FIG. Then, the low-temperature and low-pressure gas-state refrigerant is compressed by the second compressor 23 and discharged as a high-temperature and high-pressure gas refrigerant. The high-temperature and high-pressure gas refrigerant discharged from the second compressor 23 flows into the second outdoor heat exchanger 25 via the second four-way valve 24. The second outdoor heat exchanger 25 functions as a condenser, and the high-temperature and high-pressure refrigerant flowing into the second outdoor heat exchanger condenser 25 dissipates heat to the outdoor air and is condensed into a high-pressure liquid refrigerant. .. The high-pressure liquid refrigerant flowing out of the second outdoor heat exchanger 25 flows into the second expansion device 27 and the third expansion device 37, and is expanded and depressurized to become a low-temperature low-pressure gas-liquid two-phase refrigerant. The gas-liquid two-phase refrigerant flowing out of the second expansion device 27 and the third expansion device 37 flows into the second chamber heat exchanger 22 and the third chamber heat exchanger 32. The second room heat exchanger 22 and the third room heat exchanger 32 function as evaporators, and the gas-liquid two-phase refrigerant flowing into the second room heat exchanger 22 and the third room heat exchanger 32 is combined with the room air. It exchanges heat and evaporates to become a low-temperature, low-pressure gas refrigerant. The gas refrigerant flowing out from the second chamber heat exchanger 22 and the third chamber heat exchanger 32 is sucked into the second compressor 23 and compressed again. As a result, the air in the room R is cooled.

FIG. 4 is a schematic configuration diagram of the outside air supply unit 30 according to the first embodiment. The outside air supply unit 30 includes a housing 31, an air supply fan 33, an exhaust fan 34, a total heat exchanger 35, a third indoor heat exchanger 32, and a first indoor heat exchanger 12. .. The supply air passage 310 and the exhaust air passage 320 are formed independently of each other in the housing 31. In FIG. 4, the air supply air passage 310 is shown by a solid line, and the exhaust air passage 320 is shown by a broken line.

The air supply air passage 310 takes in the outdoor air OA by the air supply fan 33, passes it through the total heat exchanger 35, the third indoor heat exchanger 32, and the first indoor heat exchanger 12, and supplies it to the indoor R as the adjusting air SA. It is a wind path to do. In the air supply air passage 310, the first chamber heat exchanger 12 and the third chamber heat exchanger 32 are arranged on the downstream side of the total heat exchanger 35. Further, the third chamber heat exchanger 32 is arranged on the upstream side of the first chamber heat exchanger 12. The exhaust air passage 320 is an air passage that takes in the indoor air RA by the exhaust fan 34, passes it through the total heat exchanger 35, and discharges it to the outside as an exhaust EA.

The total heat exchanger 35 has a structure in which, for example, air passages orthogonal to each other are alternately laminated, and the indoor air RA and the outdoor air OA pass through the air passages to cause total heat between both airflows. Make an exchange. As shown in FIG. 3, the third chamber heat exchanger 32 constitutes a part of the second refrigerant circuit 200 and functions as an evaporator during the cooling and dehumidifying operation. Further, as shown in FIG. 2, the first chamber heat exchanger 12 constitutes a part of the first refrigerant circuit 100 and functions as an evaporator during the cooling and dehumidifying operation.

Further, an indoor humidity sensor 301 for detecting the humidity Xa of the indoor air RA is arranged at the suction portion of the indoor air RA of the exhaust air passage 320. Further, an outside air temperature sensor 303 is arranged at a suction portion of outdoor air OA of the air supply air passage 310.

FIG. 5 is an air diagram showing changes in the air temperature and humidity of the outside air supply unit 30 during the cooling and dehumidifying operation. The vertical axis of FIG. 5 shows the absolute humidity, and the horizontal axis shows the dry-bulb temperature. First, the (T0) outdoor air OA introduced into the air supply air passage 310 from the air supply port exchanges heat with the indoor air RA flowing through the exhaust air passage 320 in the total heat exchanger 35, and the temperature and humidity are lowered (T1). ). Then, it is further cooled and dehumidified by the third chamber heat exchanger 32 arranged on the downstream side of the total heat exchanger 35 (T2). After that, it is further cooled and dehumidified by the first indoor heat exchanger 12 (T3), and is supplied to the indoor R as the adjusting air SA.

That is, in the present embodiment, the outdoor air OA is performed in two stages of the third indoor heat exchanger 32 whose heat source is the internal conditioning outdoor unit 20 and the first indoor heat exchanger 12 whose heat source is the outdoor conditioning outdoor unit 10. Cool and dehumidify. As a result, the latent heat load of the external air conditioner 1 is reduced as compared with the case where the outdoor air OA is cooled and dehumidified only by the first indoor heat exchanger 12, so that the evaporation temperature of the external air conditioner 1 can be increased. As a result, the air conditioning load in the indoor R can be reduced while suppressing the increase in the power consumption of the external air conditioner 1.

Subsequently, the control by the control device 5 when the air conditioning system 50 performs the cooling / dehumidifying operation will be described. FIG. 6 is a functional block diagram of the control device 5 of the first embodiment. As shown in FIG. 6, the control device 5 includes a first evaporation temperature determination unit 51, a second evaporation temperature determination unit 52, a first control unit 53, and a second control unit 54. The control device 5 is a CPU (also referred to as a central processing unit, a central processing unit, a processing unit, an arithmetic unit, a microprocessor, a microcomputer, or a processor) that executes a program stored in dedicated hardware or a memory (not shown). Consists of. When the control device 5 is dedicated hardware, the control device 5 may be, for example, a single circuit, a composite circuit, an ASIC (Application Specific Integrated Circuit), an FPGA (Field-Programmable Gate Array), or a combination thereof. Applicable. Each of the functional units realized by the control device 5 may be realized by individual hardware, or each functional unit may be realized by one hardware.

When the control device 5 is a CPU, each function executed by the control device 5 is realized by software, firmware, or a combination of software and firmware. Software and firmware are written as programs and stored in memory. The CPU realizes each function of the control device 5 by reading and executing a program stored in the memory. Here, the memory is a non-volatile or volatile semiconductor memory such as a RAM, a ROM, a flash memory, an EPROM, or an EEPROM. It should be noted that some of the functions of the control device 5 may be realized by dedicated hardware, and some may be realized by software or firmware.

The first evaporation temperature determination unit 51 determines the first evaporation temperature Too, which is a control target value of the evaporation temperature of the first chamber heat exchanger 12 in the first refrigerant circuit 100. Specifically, the first evaporation temperature determination unit 51 determines the first evaporation temperature Teo according to ΔX, which is the difference between the indoor humidity Xa detected by the indoor humidity sensor 301 and the indoor target humidity Xm. The indoor target humidity Xm is preset by the user and stored in the memory of the control device 5. The first evaporation temperature determining unit 51 lowers the first evaporation temperature Teo because the latent heat load is large when ΔX is large, and raises the first evaporation temperature Teo because the latent heat load is small when ΔX is small.

FIG. 7 is a diagram illustrating a method for determining the first evaporation temperature Too in the first embodiment. First, the first evaporation temperature determining unit 51 sets in advance the upper limit Teo_max and the lower limit Teo_min of the first evaporation temperature Teo. Then, the first evaporation temperature Too is determined within the range of the upper limit Teo_max and the lower limit Teo_min according to ΔX.

Specifically, when ΔX <0, the first evaporation temperature determining unit 51 sets the first evaporation temperature Too = Teo_max, and when ΔX> ΔX ₁ , sets the first evaporation temperature Teo = Teo_min. Further, the first evaporation temperature determining unit 51 sets the first evaporation temperature Teo = α × ΔX, assuming that the first evaporation temperature Teo and ΔX are in a proportional relationship when 0 ≦ ΔX ≦ ΔX ₁ . The proportionality constant α in this case is (Teo_max-Teo_min) / ΔX ₁ . Further, ΔX ₁ is a threshold value indicating an allowable difference from the indoor target humidity Xm, which may be set in advance and stored in a memory, or may be arbitrarily changed by the user.

The second evaporation temperature determination unit 52 determines the second evaporation temperature Tei, which is the control target value of the evaporation temperature of the second room heat exchanger 22 and the third room heat exchanger 32 in the second refrigerant circuit 200. Specifically, the second evaporation temperature determination unit 52 determines the second evaporation temperature Tei according to ΔT, which is the difference between the indoor temperature Ta and the indoor target temperature Tm detected by the indoor temperature sensor 201. The indoor target temperature Tm is preset by the user and stored in the memory of the control device 5. The second evaporation temperature determination unit 52 lowers the second evaporation temperature Tei because the sensible heat load is high when ΔT is large, and raises the second evaporation temperature Tei because the sensible heat load is low when ΔT is small.

When a plurality of indoor temperature sensors 201 are arranged in the indoor R, the second evaporation temperature determining unit 52 has the maximum difference ΔT between the indoor temperature Ta and the indoor target temperature Tm detected by each indoor temperature sensor 201. The second evaporation temperature Tei is determined according to the value of ΔT of. Further, the second evaporation temperature determination unit 52 determines the second evaporation temperature Tei according to the maximum value of ΔT even when the indoor target temperature Tm is set for each indoor temperature sensor 201. As a result, it is possible to prevent the sensible heat capacity from becoming insufficient.

FIG. 8 is a diagram illustrating a method for determining the second evaporation temperature Tei in the first embodiment. First, the second evaporation temperature determining unit 52 sets in advance the upper limit Tei_max and the lower limit Tei_min of the second evaporation temperature Tei. Then, the second evaporation temperature Tei is determined within the range of the upper limit Tei_max and the lower limit Tei_min according to ΔT.

Specifically, the second evaporation temperature determination unit 52 sets the second evaporation temperature Tei = Tei_max when ΔT <0, and sets the second evaporation temperature Tei = Tei_min when ΔT> ΔT ₁ . Further, the second evaporation temperature determining unit 52 sets the second evaporation temperature Tei = β × ΔT, assuming that the second evaporation temperature Tei and ΔT are in a proportional relationship when 0 ≦ ΔT ≦ ΔT ₁ . The proportionality constant β in this case is (Tei_max-Tei_min) / ΔT ₁ . Further, ΔT ₁ is a threshold value indicating an allowable difference from the indoor target temperature Tm, which may be set in advance and stored in a memory, or may be arbitrarily changed by the user.

Further, the first evaporation temperature determining unit 51 and the second evaporation temperature determining unit 52 may change the first evaporation temperature Teo and the second evaporation temperature Tei, respectively, according to the state of the room R. For example, in the first evaporation temperature determination unit 51, even if the second evaporation temperature Tei determined by the second evaporation temperature determination unit 52 is the lower limit Tei_min, the difference ΔT is the threshold value ΔT ₁ or more, and the first When the 1 evaporation temperature Too is larger than the lower limit Teo_min, the first evaporation temperature Too may be changed to the lower limit Teo_min. That is, when the sensible heat load cannot be processed only by the second chamber heat exchanger 22 and the third chamber heat exchanger 32 and the evaporation temperature of the first chamber heat exchanger 12 can be lowered, the first evaporation temperature The determination unit 51 may lower the first evaporation temperature Too to the lower limit Theo_min. As a result, the sensible heat treatment capacity of the first chamber heat exchanger 12 is improved, and the shortage of the sensible heat capacity is suppressed.

Further, in the second evaporation temperature determination unit 52, even if the first evaporation temperature Too determined by the first evaporation temperature determination unit 51 is the lower limit Teo_min, the difference ΔX is the threshold value ΔX ₁ or more, and the second evaporation temperature is determined. 2 When the evaporation temperature Tei is larger than the lower limit Tei_min, the second evaporation temperature Tei may be changed to the lower limit Tei_min. That is, when the latent heat load cannot be processed only by the first chamber heat exchanger 12 and the evaporation temperature of the second chamber heat exchanger 22 and the third chamber heat exchanger 32 can be lowered, the second evaporation temperature is determined. The part 52 may lower the second evaporation temperature Tei to the lower limit Tei_min. As a result, the latent heat treatment capacity of the second chamber heat exchanger 22 and the third chamber heat exchanger 32 is improved, and it is possible to prevent the latent heat capacity from becoming insufficient.

Returning to FIG. 6, the first control unit 53 controls the first refrigerant circuit 100 based on the first evaporation temperature Too determined by the first evaporation temperature determination unit 51. Specifically, the first control unit 53 controls the operating frequency of the first compressor 13 so that the evaporation temperature detected by the first evaporation temperature sensor 102 becomes the first evaporation temperature Theo.

Further, even if the first evaporation temperature Too is the upper limit Teo_max, the first control unit 53 may stop the external control outdoor unit 10 when ΔX is smaller than the lower limit value ΔX_min. In this case, the first compressor 13 and the first outdoor fan 16 of the outdoor unit 10 are stopped. The lower limit value ΔXmin is, for example, 0, and may be preset and stored in the memory, or may be arbitrarily changed by the user. As a result, when it is not necessary to dehumidify the outdoor air OA, the outdoor unit 10 can be stopped to reduce the power consumption. When ΔX becomes the lower limit value ΔX_min or more, the first control unit 53 restarts the external adjustment outdoor unit 10.

The second control unit 54 controls the second refrigerant circuit 200 based on the second evaporation temperature Tei of the evaporation temperature determined by the second evaporation temperature determination unit 52. Specifically, the second control unit 54 operates the second compressor 23 so that the evaporation temperature detected by the second evaporation temperature sensor 202 and the third evaporation temperature sensor 302 becomes the second evaporation temperature Tei. Control the frequency.

Further, even if the second evaporation temperature Tei is the upper limit Tei_max, the second control unit 54 fully closes the second expansion device 27 of the indoor unit 21 and heats the second chamber when ΔT is smaller than the lower limit value ΔT_min. The inflow of the refrigerant into the exchanger 22 may be stopped. In this case, the refrigerant flows only through the third chamber heat exchanger 32. At this time, the second chamber fan 28 may also be stopped. The lower limit value ΔTmin is, for example, 0, and may be preset and stored in the memory, or may be arbitrarily changed by the user. When ΔT becomes the lower limit value ΔT_min or more, the second control unit 54 opens the second expansion device 27 and restarts the inflow of the refrigerant into the second indoor heat exchanger 22.

Further, in the second control unit 54, even if the first evaporation temperature Too is the upper limit Too_max, ΔX is smaller than the lower limit value ΔX_min, and the outside air temperature Toa detected by the outside air temperature sensor 303 is from the lower limit Toa_min. If the temperature is low, the third expansion device 37 may be fully closed to stop the inflow of the refrigerant into the third chamber heat exchanger 32. The lower limit Toa_min may be preset and stored in the memory, or may be arbitrarily changed by the user. That is, when there is no latent heat load and the outside air temperature is low, the heat exchange between the first chamber heat exchanger 12 and the third chamber heat exchanger 32 mounted on the outside air supply unit 30 may not be performed. Good. Further, when the outside air temperature Toa becomes the lower limit Toa_min or more, the second control unit 54 opens the third expansion device 37 and restarts the inflow of the refrigerant into the third chamber heat exchanger 32.

Further, in the first control unit 53 and the second control unit 54, even if the first evaporation temperature Teo is the upper limit Teo_max, ΔX is smaller than the lower limit value ΔX_min, and the second evaporation temperature Tei is the upper limit Tei_max. Even if there is, if ΔT is smaller than the lower limit value ΔT_min, the external adjustment outdoor unit 10 and the internal adjustment outdoor unit 20 may be stopped, respectively. Specifically, the first compressor 13 and the first outdoor fan 16 of the external conditioning outdoor unit 10 and the second compressor 23 and the second outdoor fan 26 of the internal conditioning outdoor unit 20 are stopped. When there is neither a latent heat load nor a sensible heat load, the power consumption can be reduced by stopping the external adjustment outdoor unit 10 and the internal adjustment outdoor unit 20.

FIG. 9 is a flowchart showing the evaporation temperature determination process according to the first embodiment. The evaporation temperature determination process is a process for determining the first evaporation temperature Teo and the second evaporation temperature Tei. The evaporation temperature determination process of FIG. 9 is performed by the control device 5 during the cooling and dehumidifying operation of the air conditioning system 50. In this process, first, the difference ΔT and the difference ΔX are calculated (S11). The difference ΔT is calculated by subtracting the indoor target temperature Tm from the indoor temperature Ta, and the difference ΔX is calculated by subtracting the indoor target humidity Xm from the indoor humidity Xa. Then, the first evaporation temperature Teo and the second evaporation temperature Tei are determined by the method described with reference to FIGS. 7 and 8 (S12).

Subsequently, it is determined whether or not the first evaporation temperature Too is the lower limit Theo_min (S13). Then, when the first evaporation temperature Too is the lower limit Theo_min (S13: YES), it is determined whether or not the difference ΔX is equal to or greater than the threshold value ΔX ₁ (S14).

When the difference ΔX is ΔX ₁ or more (S14: YES), it is determined whether or not the second evaporation temperature Tei is larger than the lower limit Tei_min (S15). Then, when the second evaporation temperature Tei is larger than the lower limit Tei_min (S15: YES), the second evaporation temperature Tei is changed to the lower limit Tei_min (S16). As a result, the latent heat treatment capacity of the second chamber heat exchanger 22 and the third chamber heat exchanger 32 is improved, and it is possible to prevent the latent heat capacity from becoming insufficient. If the difference ΔX is less than the threshold value ΔX ₁ (S14: NO), or if the second evaporation temperature Tei is already at the lower limit Tei_min (S15: NO), the process proceeds to step S20.

Further, when the first evaporation temperature Teo is not the lower limit Teo_min (S13: NO), it is determined whether or not the second evaporation temperature Tei is the lower limit Tei_min (S17). Then, when the second evaporation temperature Tei is the lower limit Tei_min (S17: YES), it is determined whether or not the difference ΔT is the threshold value ΔT ₁ or more (S18). When the difference ΔT is equal to or greater than the threshold value ΔT ₁ (S18: YES), the first evaporation temperature Too is changed to the lower limit Theo_min (S19). As a result, the sensible heat treatment capacity of the first chamber heat exchanger 12 is improved, and it is possible to prevent the sensible heat capacity from becoming insufficient. If the second evaporation temperature Tei is not the lower limit Tei_min (S17: NO), or if the difference ΔT is less than the threshold value ΔT ₁ (S18: NO), the process proceeds to step S20.

In step S20, it is determined whether or not to end the operation, and if not (S20: NO), the process returns to step S11, and the subsequent processes are repeated. When the operation is terminated (S20: YES), the cooling / dehumidifying operation by the air conditioning system 50 is stopped.

FIG. 10 is a flowchart showing the operation control process according to the first embodiment. The operation control process is a process for controlling the operation of the first refrigerant circuit 100 and the second refrigerant circuit 200. The operation control process of FIG. 10 is performed by the control device 5 after the evaporation temperature determination process or in parallel with the evaporation temperature determination process during the cooling / dehumidifying operation of the air conditioning system 50. In this process, first, it is determined whether or not the second evaporation temperature Tei is the upper limit Tei_max and the difference ΔT is smaller than the lower limit value ΔT_min (S21). When the second evaporation temperature Tei is the upper limit Tei_max and the difference ΔT is smaller than the lower limit value ΔT_min (S21: YES), the first evaporation temperature Teo is the upper limit Teo_max and the difference ΔX is from the lower limit value ΔX_min. Whether it is small or not is determined (S22).

When the first evaporation temperature Too is the upper limit Theo_max and the difference ΔX is smaller than the lower limit value ΔX_min (S22: YES), the external adjustment outdoor unit 10 and the internal adjustment outdoor unit 20 are stopped (S23). On the other hand, when the first evaporation temperature Too is not the upper limit Teo_max, or when the difference ΔX is equal to or greater than the lower limit value ΔX_min (S22: NO), the second expansion device 27 is fully closed and the second chamber heat exchanger 22 is supplied. The inflow of the refrigerant is stopped (S24).

If the second evaporation temperature Tei is not the upper limit Tei_max, or if the difference ΔT is equal to or greater than the lower limit ΔT_min (S21: NO), the first evaporation temperature Teo is the upper limit Teo_max and the difference ΔX is from the lower limit ΔX_min. Whether it is small or not is determined (S25). Then, when the first evaporation temperature Too is the upper limit Too_max and ΔX is smaller than the lower limit value ΔX_min (S25: YES), it is determined whether or not the outside air temperature Toa is lower than the lower limit Toa_min (S26).

When the outside air temperature Toa is lower than the lower limit Toa_min (S26: YES), the external adjustment outdoor unit 10 is stopped, the third expansion device 37 is fully closed, and the refrigerant to the third indoor heat exchanger 32 is charged. The inflow is stopped (S27). On the other hand, when the outside air temperature Toa is equal to or higher than the lower limit Toa_min (S26: NO), the external adjustment outdoor unit 10 is stopped (S28). Further, in step S25, when the first evaporation temperature Too is not the upper limit Teo_max, or when ΔX is equal to or higher than the lower limit value ΔX_min (S25: NO), normal control is performed (S29), and the process proceeds to step S20. In normal control, the first refrigerant circuit 100 and the second refrigerant circuit 200 are controlled based on the first evaporation temperature Teo and the second evaporation temperature Tei.

In step S20, it is determined whether or not to end the operation, and if not (S20: NO), the process returns to step S21, and the subsequent processes are repeated. When the operation is terminated (S20: YES), the cooling / dehumidifying operation by the air conditioning system 50 is stopped.

As described above, in the first embodiment, by providing the third chamber heat exchanger 32 on the upstream side in the air supply direction of the first chamber heat exchanger 12, the air flowing into the first chamber heat exchanger 12 is provided. The temperature and humidity can be lowered. That is, in the first embodiment, the outdoor air is dehumidified and cooled in two stages by two heat exchangers that constitute different refrigerant circuits and are controlled at different evaporation temperatures. Therefore, the evaporation temperature of the first indoor heat exchanger 12 can be increased as compared with the case where the temperature and humidity of the outdoor air OA are lowered only by the first indoor heat exchanger 12. While the amount of heat processed by the external air conditioner 1 and the internal air conditioner 2 is constant, the COP of the external air conditioner 1 is improved by increasing the evaporation temperature of the first indoor heat exchanger 12, and the air conditioning system 50 COP also improves. Further, by providing the third indoor heat exchanger 32 upstream of the first indoor heat exchanger 12, the amount of heat processed by the internal adjustment outdoor unit 20 increases, and the power consumption of the internal adjustment outdoor unit 20 increases. However, more than the increase in the power consumption of the internal adjustment outdoor unit 20, the power consumption of the external adjustment outdoor unit 10 can be reduced and the operating efficiency can be improved, so that the power consumption of the entire air conditioning system 50 can be reduced. Can be done.

Further, as described above, the external air conditioner 1 and the internal air conditioner 2 can be efficiently operated by setting the control target value of the evaporation temperature and performing the operation control according to the state of the indoor air temperature and the outdoor air temperature and humidity. Can be done. As a result, the power consumption of the entire air conditioning system 50 can be further reduced.

Embodiment 2.
Subsequently, the second embodiment will be described. FIG. 11 is a schematic configuration diagram of the air conditioning system 50A according to the second embodiment. The air conditioning system 50A of the second embodiment is different from the first embodiment in that it includes the person detecting means 401 and the outside air temperature / humidity sensor 304 and the control by the control device 5A. Other configurations of the air conditioning system 50A are the same as those in the first embodiment.

The person detecting means 401 is a sensor such as an entrance / exit management system that manages the entry / exit of a person into the room R, a camera arranged in the room R, or an infrared sensor or a CO ₂ concentration sensor arranged in the room R. The person detecting means 401 detects the number of people in the room R by a known method and transmits the number to the control device 5A. The outside air temperature / humidity sensor 304 is arranged at the suction portion of the outdoor air OA of the air supply air passage 310, detects the temperature (outside air temperature Toa) and humidity (outside air humidity Xoa) of the outdoor air OA, and transmits the temperature (outside air humidity Xoa) to the control device 5A.

FIG. 12 is a functional block diagram of the control device 5A according to the second embodiment. The first evaporation temperature determination unit 51 and the second evaporation temperature determination unit 52 of the second embodiment determine the first evaporation temperature Teo and the second evaporation temperature Tei based on the latent heat load Lo and the sensible heat load Si. The latent heat load Lo is the latent heat load to be processed by the first chamber heat exchanger 12, and the sensible heat load Si is the sensible heat load to be processed by the second chamber heat exchanger 22 and the third chamber heat exchanger 32. ..

Specifically, the first evaporation temperature determining unit 51 obtains the latent heat load Lt in the room R by using a known method from the outside air humidity Xoa and the number of people in the room. The number of people in the room is detected by the person detecting means 401, and the outside air humidity Xoa is detected by the outside air temperature / humidity sensor 304. Further, the first evaporation temperature determining unit 51 calculates the latent heat treatment capacity of the second chamber heat exchanger 22 and the third chamber heat exchanger 32 from the second evaporation temperature Tei_temp. The second evaporation temperature Tei_temp used here is a tentative one for obtaining the latent heat load Lo, and as described in the first embodiment, ΔT which is the difference between the indoor temperature Ta and the indoor target temperature Tm. It is required according to.

Then, the first evaporation temperature determination unit 51 estimates the latent heat load Lo based on the latent heat load Lt and the latent heat treatment capacity of the second chamber heat exchanger 22 and the third chamber heat exchanger 32. The latent heat treatment capacity of the second chamber heat exchanger 22 and the third chamber heat exchanger 32 is the sensible heat load processed by the second chamber heat exchanger 22 and the third chamber heat exchanger 32. Therefore, by subtracting the latent heat load processed by the second chamber heat exchanger 22 and the third chamber heat exchanger 32 from the latent heat load Lt, the latent heat load Lo that needs to be processed by the first chamber heat exchanger 12 is increased. Presumed. Then, the first evaporation temperature determination unit 51 calculates the evaporation temperature that can satisfy the latent heat load Lo from the indoor humidity Xa and the air volume of the outside air supply unit 30, and sets it as the first evaporation temperature Theo. The air volume of the outside air supply unit 30 is determined by the rotation speed of the air supply fan 33.

At this time, the first evaporation temperature determining unit 51 sets in advance the upper limit Teo_max and the lower limit Teo_min of the first evaporation temperature Teo. When the evaporation temperature required to process the latent heat load Lo exceeds the upper limit Teo_max, the first evaporation temperature Too is set as the upper limit Teo_max, and when the required evaporation temperature is lower than the lower limit Teo_min, the first evaporation temperature is set. Let Teo be the lower limit Teo_min. For example, when the latent heat load Lo is 0, the first evaporation temperature determining unit 51 sets the first evaporation temperature Too as the upper limit Teo_max.

The second evaporation temperature determining unit 52 obtains the sensible heat load St by using a known method from the outside air temperature Toa, the indoor target temperature Tm, the building specifications, the number of people in the room, and the like. Here, the building specifications include information about the outer wall, windows, lighting fixtures, and the like, and are stored in advance in the memory of the control device 5A. In addition, the number of people in the room is detected by the person detecting means 401. Then, the second evaporation temperature determination unit 52 calculates the microheat treatment capacity of the first chamber heat exchanger 12 from the first evaporation temperature Theo_temp. The first evaporation temperature Teo_temp used here is a tentative one for obtaining the sensible heat load Si, and is the difference between the indoor humidity Xa and the indoor target humidity Xm as described in the first embodiment. It is obtained according to ΔX.

Then, the second evaporation temperature determination unit 52 estimates the sensible heat load Si based on the sensible heat load St and the sensible heat treatment capacity of the first chamber heat exchanger 12. The sensible heat treatment capacity of the first chamber heat exchanger 12 is the sensible heat load processed by the first chamber heat exchanger 12. Therefore, by subtracting the sensible heat load processed by the first chamber heat exchanger 12 from the sensible heat load St, the sensible heat that needs to be processed by the second chamber heat exchanger 22 and the third chamber heat exchanger 32 needs to be processed. The load Si is estimated. Then, the second evaporation temperature determination unit 52 calculates the evaporation temperature that can satisfy the sensible heat load Si according to the sensible heat load Si from the indoor temperature Ta and the air volume of the indoor unit 21, and the second evaporation temperature. Let it be Tei. The air volume of the indoor unit 21 is determined by the rotation speed of the second indoor fan 28.

Further, the second evaporation temperature determination unit 52 sets in advance the upper limit Tei_max and the lower limit Tei_min of the second evaporation temperature Tei. Then, when the evaporation temperature required for processing the sensible heat load Si exceeds the upper limit Tei_max, the second evaporation temperature Tei is set as the upper limit Tei_max, and when the required evaporation temperature is lower than the lower limit Tei_min, the second evaporation Let the temperature Tei be the lower limit Tei_min. For example, when the sensible heat load Si is 0, the second evaporation temperature determining unit 52 sets the second evaporation temperature Tei as the upper limit Tei_max.

Further, the first evaporation temperature determining unit 51 and the second evaporation temperature determining unit 52 may change the first evaporation temperature Teo and the second evaporation temperature Tei, respectively, according to the state of the room R. For example, the first evaporation temperature determining unit 51 may change the first evaporation temperature Teo when the estimated sensible heat load Si cannot be processed even if the second evaporation temperature Tei is the lower limit Tei_min. Specifically, the first evaporation temperature determining unit 51 obtains a sensible heat load Si_min that can be processed when the second evaporation temperature Tei is the lower limit Tei_min. Then, the remaining sensible heat load Si_rem obtained by subtracting the processable sensible heat load Si_min from the estimated sensible heat load Si is obtained. Then, the first evaporation temperature Teo_rev capable of processing the remaining sensible heat load Si_rem is obtained. The first evaporation temperature determination unit 51 compares the first evaporation temperature Teo determined based on the latent heat load Lo with the first evaporation temperature Teo_rev obtained from the remaining sensible heat load Si_rem, and the lower one is the new first. The evaporation temperature is Teo. The first evaporation temperature Too is larger than the lower limit Theo_min. As a result, the sensible heat treatment capacity of the first chamber heat exchanger 12 is improved, and the shortage of the sensible heat capacity is suppressed.

The second evaporation temperature determination unit 52 may change the second evaporation temperature Tei even if the first evaporation temperature Teo is the lower limit Teo_min, if the estimated latent heat load Lo cannot be satisfied. Specifically, the second evaporation temperature determining unit 52 obtains a latent heat load Lo_min that can be processed when the first evaporation temperature Too is the lower limit Teo_min. Then, the remaining latent heat load Lo_rem obtained by subtracting the latent heat load Lo_min that can be processed from the estimated latent heat load Lo is obtained. Then, the second evaporation temperature Tei_rev capable of processing the remaining latent heat load Lo_rem is obtained. The second evaporation temperature determination unit 52 compares the second evaporation temperature Tei determined based on the sensible heat load Si with the second evaporation temperature Tei_rev obtained from the remaining latent heat load Lo_rem, and the lower one is the new second. The evaporation temperature is Tei. The second evaporation temperature Tei is larger than the lower limit Tei_min. As a result, the latent heat treatment capacity of the second chamber heat exchanger 22 and the third chamber heat exchanger 32 is improved, and it is possible to prevent the latent heat capacity from becoming insufficient.

The first control unit 53 controls the first refrigerant circuit 100 based on the first evaporation temperature Too determined by the first evaporation temperature determination unit 51, as in the first embodiment. Further, the first control unit 53 may stop the external adjustment outdoor unit 10 when the estimated latent heat load Lo is 0. As a result, when dehumidification by the first indoor heat exchanger 12 is unnecessary, the external conditioning outdoor unit 10 can be stopped to reduce power consumption. When the latent heat load Lo exceeds 0, the first control unit 53 restarts the external control outdoor unit 10.

The second control unit 54 controls the second refrigerant circuit 200 based on the second evaporation temperature Tei determined by the second evaporation temperature determination unit 52, as in the first embodiment. Further, when the estimated sensible heat load Si is 0, the second control unit 54 completely closes the second expansion device 27 arranged in the indoor unit 21 and closes the second indoor heat exchanger of the indoor unit 21. The inflow of the refrigerant to 22 may be stopped. As a result, the refrigerant flows only in the third chamber heat exchanger 32 arranged in the outside air supply unit 30. At this time, the second chamber fan 28 may also be stopped.

Further, when the estimated latent heat load Lo is 0 and the outside air temperature Toa is lower than the lower limit Toa_min, the second control unit 54 fully closes the third expansion device 37 and sets the third chamber heat exchanger. The inflow of the refrigerant to 32 may be stopped. That is, when there is no latent heat load and the outside air temperature is low, the heat exchange between the first chamber heat exchanger 12 and the third chamber heat exchanger 32 mounted on the outside air supply unit 30 may not be performed. Good. Further, when the outside air temperature Toa exceeds the lower limit Toa_min, the second control unit 54 opens the third expansion device 37 and restarts the inflow of the refrigerant into the third chamber heat exchanger 32.

Further, the first control unit 53 and the second control unit 54 stop the external adjustment outdoor unit 10 and the internal adjustment outdoor unit 20, respectively, when the estimated sensible heat load Si and the latent heat load Lo are both 0. Specifically, the first compressor 13 and the first outdoor fan 16 of the external conditioning outdoor unit 10 and the second compressor 23 and the second outdoor fan 26 of the internal conditioning outdoor unit 20 are stopped. When there is neither a latent heat load nor a sensible heat load, the power consumption can be reduced by stopping the external adjustment outdoor unit 10 and the internal adjustment outdoor unit 20.

FIG. 13 is a flowchart showing the evaporation temperature determination process according to the second embodiment. The evaporation temperature determination process is a process for determining the first evaporation temperature Teo and the second evaporation temperature Tei. The evaporation temperature determination process of FIG. 13 is carried out by the control device 5A during the cooling and dehumidifying operation of the air conditioning system 50A. In this process, first, the latent heat load Lo and the sensible heat load Si are calculated (S101). Then, the first evaporation temperature Teo and the second evaporation temperature Tei are determined, respectively, based on the calculated latent heat load Lo and sensible heat load Si (S102).

Subsequently, it is determined whether or not the first evaporation temperature Too is the lower limit Theo_min (S103). Then, when the first evaporation temperature Too is the lower limit Teo_min (S103: YES), it is determined whether or not the latent heat load Lo can be processed at the first evaporation temperature Too (S104). Then, when the latent heat load Lo cannot be processed (S104: NO), the second evaporation temperature Tei_rev capable of processing the remaining latent heat load Lo_rem is calculated (S105). The remaining latent heat load Lo_rem is obtained by subtracting the latent heat load Lo_min that can be processed when the evaporation temperature of the first chamber heat exchanger 12 is the lower limit Teo_min from the latent heat load Lo.

Then, it is determined whether or not the second evaporation temperature Tei_rev is lower than the second evaporation temperature Tei determined in step S102 (S106). When the second evaporation temperature Tei_rev is lower than the second evaporation temperature Tei (S106: YES), the second evaporation temperature Tei_rev is set as the new second evaporation temperature Tei (S107). On the other hand, when the second evaporation temperature Tei_rev is equal to or higher than the second evaporation temperature Tei (S106: NO), the process proceeds to step S113 without changing the second evaporation temperature Tei.

Further, when the first evaporation temperature Teo is not the lower limit Teo_min (S103: NO), it is determined whether or not the second evaporation temperature Tei is the lower limit Tei_min (S108). Then, when the second evaporation temperature Tei is the lower limit Tei_min (S108: YES), it is determined whether or not the sensible heat load Si can be processed at the second evaporation temperature Tei (S109). Then, when the sensible heat load Si cannot be processed (S109: NO), the first evaporation temperature Teo_rev capable of processing the remaining sensible heat load Si_rem is calculated (S110). The remaining sensible heat load Si_rem is obtained by subtracting the sensible heat load Si_min that can be processed when the evaporation temperature of the second chamber heat exchanger 22 and the third chamber heat exchanger 32 is Tei_min from the sensible heat load Si.

Then, it is determined whether or not the first evaporation temperature Teo_rev is lower than the first evaporation temperature Teo calculated in step S102 (S111). Here, when the first evaporation temperature Teo_rev is lower than the first evaporation temperature Teo (S111: YES), the first evaporation temperature Teo_rev is set as a new first evaporation temperature Teo (S112). On the other hand, when the first evaporation temperature Teo_rev is equal to or higher than the first evaporation temperature Teo (S111: NO), the process proceeds to step S113 without changing the first evaporation temperature Teo.

In step S113, it is determined whether or not to end the operation, and if not (S113: NO), the process returns to step S101, and the subsequent processes are repeated. When the operation is terminated (S113: YES), the cooling / dehumidifying operation by the air conditioning system 50A is stopped.

FIG. 14 is a flowchart showing the operation control process according to the second embodiment. The operation control process is a process for controlling the operation of the first refrigerant circuit 100 and the second refrigerant circuit 200. The operation control process of FIG. 14 is performed by the control device 5A in parallel with the evaporation temperature determination process during the cooling and dehumidifying operation of the air conditioning system 50A. In this process, first, it is determined whether or not the sensible heat load Si is 0 (S201). Then, when the sensible heat load Si is 0 (S201: YES), it is determined whether or not the latent heat load Lo is 0 (S202). When the latent heat load Lo is 0 (S202: YES), the internal adjustment outdoor unit 20 and the external adjustment outdoor unit 10 are stopped (S203). On the other hand, when the latent heat load Lo is not 0 (S202: NO), the second expansion device 27 is fully closed and the inflow of the refrigerant into the second chamber heat exchanger 22 is stopped (S204).

Further, when the sensible heat load Si is not 0 (S201: NO), it is determined whether or not the latent heat load Lo is 0 (S205). Then, when the latent heat load Lo is 0 (S205: YES), it is determined whether or not the outside air temperature Toa is lower than the lower limit Toa_min (S206). When the outside air temperature Toa is lower than the lower limit Toa_min (S206: YES), the external conditioning outdoor unit 10 is stopped, the third expansion device 37 is fully closed, and the refrigerant to the third indoor heat exchanger 32 is charged. The inflow is stopped (S207). On the other hand, when the outside air temperature Toa is equal to or higher than the lower limit Toa_min (S206: NO), the external adjustment outdoor unit 10 is stopped (S208).

Further, in S205, when the latent heat load Lo is not 0 (S205: NO), normal control is performed (S209), and the process proceeds to step S113. In normal control, the first refrigerant circuit 100 and the second refrigerant circuit 200 are controlled based on the first evaporation temperature Teo and the second evaporation temperature Tei.

In step S113, it is determined whether or not to end the operation, and if not (S113: NO), the process returns to step S201, and the subsequent processes are repeated. When the operation is terminated (S113: YES), the cooling / dehumidifying operation by the air conditioning system 50 is stopped.

As described above, the same effect as that of the first embodiment can be obtained in the second embodiment. Further, in the second embodiment, the control target value of the evaporation temperature of the first chamber heat exchanger 12, the second chamber heat exchanger 22, and the third chamber heat exchanger 32 can be determined according to the estimated air conditioning load. Therefore, the power consumption of the air conditioning system 50A can be further suppressed while maintaining the comfort of the indoor R, and the efficiency can be improved.

Although the embodiments of the present invention have been described above with reference to the drawings, the specific configuration of the present invention is not limited to this, and can be changed without departing from the gist of the invention. For example, the outside air supply unit 30 may be provided with a plurality of third chamber heat exchangers 32. Further, in the above embodiment, the second expansion device 27 and the third expansion device 37 corresponding to the second chamber heat exchanger 22 and the third chamber heat exchanger 32 are provided, respectively, but the second chamber heat exchange is provided. It may be configured to include one expansion device corresponding to both the vessel 22 and the third chamber heat exchanger 32. Further, in the above embodiment, both the external air conditioner 1 and the internal air conditioner 2 are controlled by the control device 5, but the external air conditioner 1 and the internal air conditioner 2 are individually provided with a control device. May be.

Further, the control of the first embodiment and the control of the second embodiment can be combined as appropriate. For example, either one of the first evaporation temperature Teo and the second evaporation temperature Tei may be determined by the method of the first embodiment, and the other may be determined by the method of the second embodiment. Further, the information such as the number of people in the room for estimating the latent heat load Lo and the sensible heat load Si is not limited to that detected by each sensor, and may be input by the user.

Further, the upper limit Teo_max of the first evaporation temperature Teo of the evaporation temperature of the first chamber heat exchanger 12 may be set as the second evaporation temperature Tei. When the evaporation temperature of the first chamber heat exchanger 12 is higher than the evaporation temperature of the second chamber heat exchanger 22 and the third chamber heat exchanger 32, the air passing through the first chamber heat exchanger 12 is not dehumidified. Therefore, by setting the upper limit Teo_max as described above, the evaporation temperature of the first chamber heat exchanger 12 is prevented from exceeding the evaporation temperature of the second chamber heat exchanger 22 and the third chamber heat exchanger 32. Can be done. As a result, when the indoor target humidity Xm is reached by dehumidification by the second indoor heat exchanger 22 and the third indoor heat exchanger 32, the outdoor adjustment outdoor unit 10 can be stopped and the power consumption can be reduced.

Further, as another modification, the upper limit Teo_max of the first evaporation temperature Too may be the evaporation temperature of the third chamber heat exchanger 32 detected by the third evaporation temperature sensor 302. By setting the upper limit Teo_max in this way, the first evaporation temperature Too does not exceed the evaporation temperature of the third chamber heat exchanger 32 based on the actual evaporation temperature of the third chamber heat exchanger 32. Can be done. As a result, when the target humidity is reached by dehumidification by the third indoor heat exchanger 32, the external adjustment outdoor unit 10 can be stopped and the power consumption can be reduced.

1 External conditioner, 2 Internal conditioner, 5, 5A controller, 10 External adjustment outdoor unit, 12 1st indoor heat exchanger, 13 1st compressor, 14 1st four-way valve, 15 1st outdoor heat exchanger, 16 1st outdoor fan, 17 1st expansion device, 20 internal conditioning outdoor unit, 21 indoor unit, 22 2nd indoor heat exchanger, 23 2nd compressor, 24 2nd four-way valve, 25 2nd outdoor heat exchanger, 26 2nd outdoor fan, 27 2nd expansion device, 28 2nd indoor fan, 30 outside air supply unit, 30a external adjustment part, 30b internal adjustment part, 31 housing, 32 3rd indoor heat exchanger, 33 air supply fan, 34 Exhaust fan, 35 Total heat exchanger, 37 Third expansion device, 40a, 40b Refrigerant piping, 50, 50A Air conditioning system, 51 First evaporation temperature determination unit, 52 Second evaporation temperature determination unit, 53 First control unit 54 Second Control Unit, 100 First Refrigerant Circuit, 102 First Refrigerant Temperature Sensor, 200 Second Refrigerant Circuit, 201 Indoor Temperature Sensor, 202 Second Refrigerant Temperature Sensor, 301 Indoor Humidity Sensor, 302 Third Evaporation Temperature Sensor, 303 Outside air temperature sensor, 304 outside temperature / humidity sensor, 310 air supply air passage, 320 exhaust air passage, 401 person detection means, C ceiling, EA exhaust, OA outdoor air, R room, RA room air, SA conditioned air.

Claims (21)

A first refrigerant circuit including a first compressor, a first outdoor heat exchanger, and a first indoor heat exchanger,
A second refrigerant circuit including a second compressor, a second outdoor heat exchanger, a second indoor heat exchanger, and a third indoor heat exchanger.
An indoor unit equipped with the second indoor heat exchanger and controlling the temperature of the indoor air,
An outside air supply unit including the first indoor heat exchanger and the third indoor heat exchanger and adjusting the humidity of the taken-in outdoor air, and
Air conditioning system with. The outside air supply unit is
The air supply air passage that takes in the outdoor air and supplies it indoors,
It has an exhaust air passage that takes in the indoor air and discharges it to the outside.
The air conditioning system according to claim 1, wherein the third chamber heat exchanger is arranged on the upstream side of the first chamber heat exchanger in the air supply air passage. The first evaporation temperature, which is a control target value of the evaporation temperature when the first chamber heat exchanger is an evaporator, and the case where the second chamber heat exchanger and the third chamber heat exchanger are evaporators. The air conditioning system according to claim 1 or 2, further comprising a control device for determining a second evaporation temperature, which is a control target value of the evaporation temperature. The air conditioning system according to claim 3, wherein the control device determines the first evaporation temperature between a preset upper limit and a lower limit according to a difference between an indoor humidity and an indoor target humidity. The air conditioning system according to claim 4, wherein the control device determines the second evaporation temperature according to a difference between a room temperature and a room target temperature between a preset upper limit and a lower limit. The control device changes the first evaporation temperature to the lower limit when the second evaporation temperature is the lower limit and the difference between the room temperature and the indoor target temperature is equal to or more than the threshold value during the cooling and dehumidifying operation. The air conditioning system according to claim 5. The control device changes the second evaporation temperature to the lower limit when the first evaporation temperature is the lower limit and the difference between the indoor humidity and the indoor target humidity is equal to or greater than the threshold during the cooling and dehumidifying operation. The air conditioning system according to claim 5 or 6. The control device is requested to stop the first compressor when the first evaporation temperature is the upper limit and the difference between the indoor humidity and the indoor target humidity is smaller than the lower limit value during the cooling and dehumidifying operation. Item 4. The air conditioning system according to any one of Items 5 to 7. When the second evaporation temperature is the upper limit and the difference between the room temperature and the room target temperature is smaller than the lower limit value during the cooling / dehumidifying operation, the control device to the second room heat exchanger. The air conditioning system according to any one of claims 5 to 8, wherein the inflow of the refrigerant is stopped. In the control device, during the cooling / dehumidifying operation, the first evaporation temperature is the upper limit, the difference between the indoor humidity and the indoor target humidity is smaller than the lower limit, and the outside air temperature is lower than the lower limit. The air conditioning system according to any one of claims 5 to 9, wherein the inflow of the refrigerant into the third chamber heat exchanger is stopped. In the control device, the first evaporation temperature is the upper limit, the difference between the indoor humidity and the indoor target humidity is smaller than the lower limit value, and the second evaporation temperature is the upper limit during the cooling and dehumidifying operation. The air according to any one of claims 5 to 10, which is an upper limit and the difference between the indoor temperature and the indoor target temperature is smaller than the lower limit value, the first compressor and the second compressor are stopped. Harmony system. The air conditioning system according to any one of claims 5 to 11, wherein the control device has the second evaporation temperature as the upper limit of the first evaporation temperature. An evaporation temperature sensor for detecting the evaporation temperature of the third chamber heat exchanger is further provided.
The air conditioning system according to any one of claims 5 to 11, wherein the control device has an evaporation temperature detected by the evaporation temperature sensor as the upper limit of the first evaporation temperature. The air conditioning system according to claim 3, wherein the control device determines the first evaporation temperature according to a latent heat load between a preset upper limit and a lower limit. The air conditioning system according to claim 14, wherein the control device determines the second evaporation temperature according to a sensible heat load between a preset upper limit and a lower limit. The air conditioning system according to claim 15, wherein the control device changes the first evaporation temperature when the sensible heat load cannot be processed even if the second evaporation temperature is the lower limit during the cooling / dehumidifying operation. The air conditioning system according to claim 15 or 16, wherein the control device changes the second evaporation temperature when the latent heat load cannot be processed even if the first evaporation temperature is the lower limit during the cooling and dehumidifying operation. .. The air conditioning system according to any one of claims 15 to 17, wherein the control device stops the first compressor when the latent heat load is 0 during the cooling / dehumidifying operation. The air conditioning system according to any one of claims 15 to 18, wherein the control device stops the inflow of the refrigerant into the second chamber heat exchanger when the sensible heat load is 0 during the cooling and dehumidifying operation. .. Claims 15 to 19 of the control device stop the inflow of the refrigerant into the third chamber heat exchanger when the latent heat load is 0 and the outside air temperature is lower than the lower limit during the cooling and dehumidifying operation. The air conditioning system according to any one of the above. Any of claims 15 to 20, wherein the control device stops the first compressor and the second compressor when the sensible heat load is 0 and the latent heat load is 0 during the cooling and dehumidifying operation. The air conditioning system described in item 1.

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