JP7209485B2 - air conditioning system - Google Patents

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an air conditioning system having an outside air supply device that supplies outside air to a space to be air-conditioned, such as a room.

Air conditioners include direct expansion air conditioners and inter-expansion air conditioners. A direct-expansion air conditioner and an inter-expansion air conditioner differ in the air conditioning method for supplying air to an air-conditioned space. In a direct expansion air conditioner, a refrigerant is supplied to a heat exchanger that heats or cools air supplied to a space to be air-conditioned. In the direct expansion air conditioner, the refrigerant supplied to the heat exchanger cools or heats the air supplied to the air-conditioned space. On the other hand, in an inter-expansion air conditioner, water is heated or cooled by a refrigerant inside the heat source device. Then, in the inter-expansion air conditioner, the water is supplied to a heat exchanger that heats or cools the air that is supplied to the space to be air-conditioned. In the inter-expansion air conditioner, the water supplied to the heat exchanger cools or heats the air supplied to the air-conditioned space.

Currently, direct expansion type air conditioners such as multi-air conditioners for buildings are widely used in small and medium-sized buildings. However, from the viewpoint of suppressing chlorofluorocarbon emissions, inter-expansion air conditioners with a small total amount of refrigerant are being reconsidered. Therefore, it is expected that air conditioning systems using both direct expansion air conditioners and inter-expansion air conditioners will become widespread in the future.

Here, an air conditioner that heats or cools air in an air-conditioned space drawn into an indoor unit and returns the heated or cooled air to the air-conditioned space is called an internal air conditioner. Also, an air conditioner that heats or cools outside air drawn into an outside air supply unit for ventilation and returns the heated or cooled outside air to an air-conditioned space is called an outside air conditioner. An increasing number of buildings use a direct expansion air conditioner as an internal air conditioner and an inter-expansion air conditioner as an external air conditioner.

Conventionally, a direct expansion air conditioner as an internal air conditioner and an inter-expansion air conditioner as an external air conditioner are controlled independently of each other. For this reason, it can be said that there is room for reduction in the power consumption of the entire air conditioning system including the indoor air conditioner and the outdoor air conditioner.

For this reason, an air conditioning system designed to reduce power consumption is also proposed for conventional air conditioning systems equipped with direct expansion air conditioners as internal air conditioners and inter-expansion air conditioners as external air conditioners. (See Patent Document 1). Specifically, the air conditioning system described in Patent Document 1 generates a plurality of optimal load distribution functions associated with each comfort index range. Further, the air conditioning system described in Patent Literature 1 selects one of the optimum load distribution functions based on the comfort index set by the user from among the plurality of optimum load distribution functions. Then, the air conditioning system described in Patent Document 1 reduces the power consumption of the air conditioning system as a whole based on the selected optimum load distribution function. Determine the air conditioning load.

Japanese Patent No. 5951526

In the air conditioning system described in Patent Document 1, it is necessary to model each of the indoor air conditioners and the outdoor air conditioners, and create an optimum load distribution function by simulation in advance. Therefore, the air conditioning system described in Patent Literature 1 has a problem that it takes time and effort to manufacture.

The present invention has been made to solve the above-described problems, and an object of the present invention is to obtain an air conditioning system capable of suppressing time and effort in manufacturing and suppressing power consumption.

An air conditioning system according to the present invention has a first heat exchanger and a first housing that houses the first heat exchanger, and the refrigerant that flows through the first heat exchanger is sucked into the first housing. an indoor unit that cools the air in the air-conditioned space, a second heat exchanger, and a second housing that houses the second heat exchanger; an outside air supply device that cools outside air drawn into a body and supplies the cooled outside air as supply air to the air-conditioned space; a first temperature sensor that detects the temperature of the air-conditioned space; a first humidity sensor that detects the absolute humidity of the air-conditioned space, and a control device that stores the set temperature and set humidity of the air-conditioned space, and the temperature difference that is the value obtained by subtracting the set temperature from the temperature of the air-conditioned space is a first temperature difference, and a second temperature difference is a state where the temperature difference is a second temperature difference smaller than the first temperature difference. The temperature of the refrigerant flowing through the first heat exchanger when in the second temperature difference state is higher than the temperature of the refrigerant flowing through the first heat exchanger when in the first temperature difference state, and the air conditioning A state in which a humidity difference obtained by subtracting the set humidity from the absolute humidity of the target space is a first humidity difference is referred to as a first humidity difference state, and a second humidity in which the humidity difference is smaller than the first humidity difference. When the state of the difference is defined as a second humidity difference state, the temperature of the supplied air supplied from the outside air supply unit in the second humidity difference state is the same as that in the first humidity difference state. The temperature of the supplied air is higher than the temperature of the supply air supplied from the outside air supply machine, and the maximum absolute humidity of the supply air supplied from the outside air supply machine is the same as the set humidity .

The internal air conditioner mainly processes the sensible heat load, and the outdoor air conditioner mainly processes the latent heat load. By changing the temperature of the refrigerant flowing through the first heat exchanger of the indoor unit of the indoor unit and the temperature of the air supplied from the outdoor air supply device of the outdoor unit as in the present invention, the air conditioning load of the indoor unit can be made a load according to the sensible heat load, and the air conditioning load of the outdoor unit can be made a load according to the latent heat load. Therefore, the air conditioning system according to the present invention can reduce the power consumption of the air conditioning system as a whole. Also, the air conditioning system according to the present invention does not require prior complicated modeling work and simulation work. For this reason, the air conditioning system according to the present invention can also reduce the time and effort involved in manufacturing it.

BRIEF DESCRIPTION OF THE DRAWINGS It is a figure which shows schematic structure of the air conditioning system which concerns on Embodiment 1 of this invention. Fig. 2 is a diagram showing a refrigerant circuit of an internal conditioner of the air conditioning system according to Embodiment 1 of the present invention; FIG. 2 is a diagram showing a refrigerant circuit and a water circuit of the outdoor unit of the air conditioning system according to Embodiment 1 of the present invention; 1 is a diagram showing a schematic configuration of an outside air supply device of an outdoor unit in the air conditioning system according to Embodiment 1 of the present invention; FIG. FIG. 4 is a diagram for explaining a method of determining a target evaporation temperature of refrigerant flowing through the first heat exchanger in the air conditioning system according to Embodiment 1 of the present invention; FIG. 4 is a diagram for explaining a method of determining a target supply air temperature of supply air supplied from an outside air supplier into a room in the air conditioning system according to Embodiment 1 of the present invention; FIG. 4 is a psychrometric diagram for explaining a method of determining a target water temperature of water flowing through a second heat exchanger in the air conditioning system according to Embodiment 1 of the present invention; FIG. 4 is a psychrometric diagram for explaining a method of calculating a target water temperature of water flowing through a second heat exchanger in the air conditioning system according to Embodiment 1 of the present invention; FIG. 4 is a diagram for explaining a control flow when the air-conditioning system according to Embodiment 1 of the present invention performs cooling and dehumidifying operation; FIG. 2 is a diagram showing a schematic configuration of an air conditioning system according to Embodiment 2 of the present invention; FIG. 10 is a diagram showing a schematic configuration of an outside air supply device of an outdoor unit in an air conditioning system according to Embodiment 2 of the present invention; FIG. 9 is a psychrometric diagram for explaining a method of determining an upper limit value of a target supply air temperature of supply air supplied from an outside air supplier into a room in the air conditioning system according to Embodiment 2 of the present invention.

Hereinafter, in each embodiment, an example of an air conditioning system according to the present invention will be described. The specific configuration of the air conditioning system according to the present invention is not limited to the configurations shown in the following embodiments, and can be changed without departing from the gist of the invention.

Embodiment 1.
FIG. 1 is a diagram showing a schematic configuration of an air conditioning system according to Embodiment 1 of the present invention. FIG. 2 is a diagram showing a refrigerant circuit of an internal conditioner of the air conditioning system according to Embodiment 1 of the present invention. FIG. 3 is a diagram showing a refrigerant circuit and a water circuit of the outdoor unit of the air conditioning system according to Embodiment 1 of the present invention. FIG. 4 is a diagram showing a schematic configuration of an outside air supply device of an outdoor unit in the air conditioning system according to Embodiment 1 of the present invention.

As shown in FIG. 1 , an air conditioning system 100 according to Embodiment 1 includes an internal air conditioner 1 and an external air conditioner 2 .

The interior conditioner 1 includes an outdoor unit 10 and an indoor unit 11 . The outdoor unit 10 is arranged outdoors. The indoor unit 11 is provided in a room 101 whose interior is an air-conditioned space. The indoor unit 11 sucks air in the room 101 to cool it, and blows out the cooled air into the room 101 . The outdoor unit 10 and the indoor unit 11 are connected by a refrigerant pipe 18 . Note that the number of the outdoor units 10 and the indoor units 11 shown in FIG. 1 is an example. For example, although one room 101 is provided with a plurality of indoor units 11 in FIG. 1 , one room 101 may be provided with one indoor unit 11 . Further, for example, one indoor unit 11 may cool a plurality of rooms 101 . Further, although the indoor air conditioner 1 includes a plurality of outdoor units 10 in FIG. 1 , the indoor air conditioner 1 may include only one outdoor unit 10 . That is, all indoor units 11 may be connected to one outdoor unit 10 .

The outdoor air conditioner 2 includes a chiller 30, which is an example of a heat source, and an outdoor air supplier 31, which is an air handling unit, for example. The chiller 30 is arranged outdoors. The outside air supply device 31 takes in outside air, cools the outside air, and supplies it into the room 101 . The chiller 30 and the outside air supply device 31 are connected by a water pipe 46 . Note that the number of chillers 30 and outside air supply devices 31 shown in FIG. 1 is an example. For example, in Embodiment 1, outside air is supplied to a plurality of rooms 101 from one outside air supply device 31 via ducts or the like. The outdoor air conditioner 2 may be provided with a plurality of outdoor air supply devices 31 , such as providing an outdoor air supply device 31 for each room 101 . Further, for example, the outdoor air conditioner 2 may be provided with a plurality of chillers 30 , such as connecting one chiller 30 to each of the plurality of outside air supply devices 31 .

As shown in FIG. 2 , the internal air conditioner 1 includes a refrigerant circuit 12 . Each component of the refrigerant circuit 12 is housed in the outdoor unit 10 or the indoor unit 11 . Specifically, the refrigerant circuit 12 includes, as components, a compressor 13, an outdoor heat exchanger 14, an expansion valve 15, and a first heat exchanger 16, which is an indoor heat exchanger. A refrigerant circuit 12 is configured by connecting these components with refrigerant pipes. That is, the refrigerant pipes connecting the components of the refrigerant circuit 12 housed in the outdoor unit 10 and the components of the refrigerant circuit 12 housed in the indoor unit 11 are the refrigerant pipes 18 shown in FIG.

The compressor 13 compresses the refrigerant. The outdoor heat exchanger 14 is a heat exchanger that functions as a condenser. The outdoor heat exchanger 14 is connected to the outlet of the compressor 13 . The outdoor heat exchanger 14 is also connected to the first heat exchanger 16 via the expansion valve 15 . The compressor 13 and the outdoor heat exchanger 14 are housed in the outdoor unit 10 . The outdoor unit 10 also houses an outdoor unit fan 19 . The outdoor unit fan 19 supplies the outdoor heat exchanger 14 with outside air to which the refrigerant flowing through the outdoor heat exchanger 14 is subjected to heat exchange.

The expansion valve 15 expands and decompresses the refrigerant. The first heat exchanger 16 is a heat exchanger that functions as an evaporator. The first heat exchanger 16 is connected to the outdoor heat exchanger 14 via the expansion valve 15 as described above. Also, the first heat exchanger 16 is connected to the suction port of the compressor 13 . The expansion valve 15 and the first heat exchanger 16 are housed in the first housing 11 a of the indoor unit 11 . An indoor unit fan 20 is also housed in the first housing 11 a of the indoor unit 11 . That is, when the indoor unit fan 20 rotates inside the first housing 11a, the air inside the room 101 is sucked into the first housing 11a. The air sucked into the first housing 11 a is cooled by the coolant flowing through the first heat exchanger 16 and blown out into the room 101 . Note that the expansion valve 15 may be housed in the outdoor unit 10 .

Here, in Embodiment 1, one refrigerant circuit 12 is provided with two indoor units 11 . Therefore, the refrigerant circuit 12 is provided with two sets of the expansion valve 15 and the first heat exchanger 16 . Each set of the expansion valve 15 and the first heat exchanger 16 is connected in parallel between the outdoor heat exchanger 14 and the suction port of the compressor 13 .

Further, as shown in FIG. 2, the refrigerant circuit 12 according to Embodiment 1 enables both the cooling operation and the heating operation in the indoor unit 11. Therefore, the four-way valve provided on the discharge side of the compressor 13 17. The four-way valve 17 switches the connection destination of the discharge port of the compressor 13 . Specifically, when the flow path of the four-way valve 17 is such that the discharge port of the compressor 13 is connected to the outdoor heat exchanger 14 , the suction port of the compressor 13 is connected to the first heat exchanger 16 . be. In this case, the outdoor heat exchanger 14 functions as a condenser, and the first heat exchanger 16 functions as an evaporator. Further, when the flow path of the four-way valve 17 is such that the discharge port of the compressor 13 is connected to the first heat exchanger 16, the suction port of the compressor 13 is connected to the outdoor heat exchanger 14. . In this case, the outdoor heat exchanger 14 functions as an evaporator, and the first heat exchanger 16 functions as a condenser. The four-way valve 17 is housed in the outdoor unit 10 . Note that the four-way valve 17 does not need to be provided if the first heat exchanger 16 does not need to function as a condenser.

As shown in FIG. 3 , the outdoor air conditioner 2 includes a refrigerant circuit 32 and a water circuit 40 . Each component of the refrigerant circuit 32 is housed in the chiller 30 . The components of water circuit 40 are housed in chiller 30 or fresh air supply 31 .

The refrigerant circuit 32 includes a compressor 33, a refrigerant-air heat exchanger 34, an expansion valve 35, and a water-refrigerant heat exchanger 36 as components. That is, the refrigerant circuit 32 is formed by connecting the refrigerant flow paths of the compressor 33, the refrigerant-air heat exchanger 34, the expansion valve 35, and the water-refrigerant heat exchanger 36 with refrigerant pipes. Compressor 33, refrigerant-to-air heat exchanger 34, expansion valve 35, and water-to-refrigerant heat exchanger 36 are housed in chiller 30, as described above. The chiller 30 also houses a chiller fan 38 .

The compressor 33 compresses the refrigerant. Refrigerant-to-air heat exchanger 34 is a heat exchanger that functions as a condenser. Specifically, the refrigerant flowing through the refrigerant-air heat exchanger 34 is cooled by outside air supplied from the chiller fan 38 and condensed. The refrigerant-air heat exchanger 34 is connected to the discharge port of the compressor 33 . The refrigerant-air heat exchanger 34 is also connected to the refrigerant channel of the water-refrigerant heat exchanger 36 via an expansion valve 35 . The expansion valve 35 expands and decompresses the refrigerant.

The water-to-refrigerant heat exchanger 36 is a heat exchanger that functions as an evaporator. Specifically, the refrigerant flowing through the refrigerant flow path of the water-refrigerant heat exchanger 36 is heated and evaporated when cooling the refrigerant flowing through the water flow path of the water-refrigerant heat exchanger 36 . The refrigerant flow path of the water-refrigerant heat exchanger 36 is connected to the refrigerant-air heat exchanger 34 via the expansion valve 35 as described above. A refrigerant channel of the water-refrigerant heat exchanger 36 is connected to the suction port of the compressor 33 . Here, as will be described later, water circulating in the water circuit 40 flows through the water flow path of the water-refrigerant heat exchanger 36 . Therefore, when the water-refrigerant heat exchanger 36 functions as an evaporator, the outside air supplied into the room 101 is cooled by the water cooled by the water-refrigerant heat exchanger 36 .

Note that the refrigerant circuit 32 according to Embodiment 1 includes a four-way valve 37 provided on the discharge side of the compressor 33 . The four-way valve 37 switches the connection destination of the discharge port of the compressor 33 . Specifically, when the flow path of the four-way valve 37 is such that the discharge port of the compressor 33 is connected to the refrigerant-air heat exchanger 34, the suction port of the compressor 33 is connected to the water-refrigerant heat exchanger 36. It is connected to the coolant channel. In this case, the refrigerant-to-air heat exchanger 34 functions as a condenser and the water-to-refrigerant heat exchanger 36 functions as an evaporator. Further, when the flow path of the four-way valve 37 is in a state where the discharge port of the compressor 33 is connected to the refrigerant flow path of the water-refrigerant heat exchanger 36, the suction port of the compressor 33 is connected to the refrigerant-air heat It is connected to the exchange 34 . In this case, the refrigerant-to-air heat exchanger 34 functions as an evaporator and the water-to-refrigerant heat exchanger 36 functions as a condenser. In this case, the outside air supplied into the room 101 is heated by the water heated by the water-refrigerant heat exchanger 36 . It should be noted that the four-way valve 37 need not be provided if there is no need to heat the outside air supplied into the room 101 .

The water circuit 40 includes a pump 41, a water-refrigerant heat exchanger 36 and a second heat exchanger 42 as components. A water circuit 40 is formed by connecting the pump 41, the water flow path of the water-refrigerant heat exchanger 36, and the second heat exchanger 42 with water pipes. As mentioned above, the components of water circuit 40 are housed in chiller 30 or fresh air supply 31 . Therefore, the water pipe connecting the components of the water circuit 40 housed in the chiller 30 and the components of the water circuit 40 housed in the outside air supplier 31 is the water pipe 46 shown in FIG.

The pump 41 discharges the sucked water and circulates the water in the water circuit 40 . As described above, the water-refrigerant heat exchanger 36 exchanges heat between the refrigerant flowing through the refrigerant channel and the water flowing through the water channel. The second heat exchanger 42 cools or heats the outside air with water flowing through the second heat exchanger 42 .

Further, the water circuit 40 according to Embodiment 1 includes a flow rate adjusting mechanism 43 that adjusts the flow rate of water flowing through the second heat exchanger 42 . This flow control mechanism 43 has a bypass pipe 44 and a three-way valve 45 . A bypass pipe 44 is provided to bypass the second heat exchanger 42 . The three-way valve 45 is provided at a connection point between the water pipe connecting the water-refrigerant heat exchanger 36 and the second heat exchanger 42 and the bypass pipe 44 . That is, one of the three openings of the three-way valve 45 is connected to the water-refrigerant heat exchanger 36 . The second of the three openings of the three-way valve 45 is connected with the second heat exchanger 42 . A third of the three openings of the three-way valve 45 is connected to the bypass pipe 44 . As the flow rate of water flowing through the bypass pipe 44 is increased by the three-way valve 45, the flow rate of water flowing through the second heat exchanger 42 decreases.

Among the components of the water circuit 40 , the pump 41 , the water-refrigerant heat exchanger 36 and the flow control mechanism 43 are housed in the chiller 30 . Among the components of the water circuit 40 , the second heat exchanger 42 is accommodated in the second housing 50 of the outside air supply device 31 . Note that the flow rate adjusting mechanism 43 may be housed in the second housing 50 of the outside air supply device 31 .

As shown in FIG. 4 , the second housing 50 of the outside air supply device 31 is formed with a first suction port 51 and a first outlet 52 . The first suction port 51 is a suction port for taking outside air into the second housing 50 . The first suction port 51 communicates with the outdoors, for example, via a duct or the like. The first air outlet 52 is an air outlet for blowing outside air taken into the second housing 50 to the outside of the second housing 50 . The first outlet 52 communicates with the inside of each room 101 via, for example, a duct. Further, the second housing 50 houses an air supply fan 55 . Here, as described above, the second housing 50 houses the second heat exchanger 42 of the water circuit 40 . Therefore, the rotation of the air supply fan 55 cools or heats the outside air sucked into the second housing 50 through the first suction port 51 by the water flowing through the second heat exchanger 42 . Then, the cooled or heated outside air is supplied into each room 101 as supply air via the first blowout port 52 and the duct.

A second suction port 53 and a second outlet 54 are also formed in the second housing 50 according to the first embodiment. The second suction port 53 is a suction port for taking the air in the room 101 into the second housing 50 . The second suction port 53 communicates with the interior of each room 101 via, for example, a duct. The second air outlet 54 is an air outlet for blowing out the air in the room 101 taken into the second housing 50 to the outside of the second housing 50 . The second outlet 54 communicates with the outside via, for example, a duct. An exhaust fan 56 is accommodated in the second housing 50 . By rotating the exhaust fan 56, the air in the room 101 is sucked into the second housing 50 from the second suction port 53, and the air in the room 101 sucked into the second housing 50 is discharged through the second air outlet. The air is blown out from 54 to the outside. In addition, the second housing 50 according to the first embodiment has a total heat exchange system in which outside air sucked from the first suction port 51 and air inside the room 101 sucked from the second suction port 53 heat exchange. A vessel 57 is also provided.

Further, as shown in FIG. 1, the air conditioning system 100 includes a plurality of sensors and a control device 60 that controls each component of the air conditioning system 100 based on the detected values of these sensors.

Specifically, the air conditioning system 100 includes a first temperature sensor 71 , a second temperature sensor 72 , a temperature sensor 73 , a first humidity sensor 81 and a second humidity sensor 82 .

The first temperature sensor 71 is a sensor that detects the temperature in the room 101, that is, the temperature of the air-conditioned space. At least one first temperature sensor 71 should be present in the room 101 . Moreover, the installation position of the first temperature sensor 71 is arbitrary as long as the temperature in the room 101 can be detected. In addition, in Embodiment 1, each indoor unit 11 is provided with the first temperature sensor 71 . The second temperature sensor 72 is a sensor that detects the temperature of outside air. The installation position of the second temperature sensor 72 is arbitrary as long as the temperature of the outside air can be detected. In the first embodiment, the second temperature sensor 72 is installed near the first suction port 51 inside the second housing 50 of the outside air supply device 31 . The temperature sensor 73 is a sensor that detects the temperature of the air supplied from the outside air supplier 31 into the room 101 . The installation position of the temperature sensor 73 is arbitrary as long as it can detect the temperature of the air supplied from the outside air supply device 31 into the room 101 . Note that in the first embodiment, the temperature sensor 73 is installed in the vicinity of the first outlet 52 inside the second housing 50 of the outside air supply device 31 . In the first embodiment, the temperature refers to the dry-bulb temperature unless otherwise specified.

The first humidity sensor 81 is a sensor that detects the absolute humidity in the room 101, that is, the temperature of the absolute humidity in the air-conditioned space. At least one first humidity sensor 81 should be present in the room 101 . Moreover, the installation position of the first humidity sensor 81 is arbitrary as long as the absolute humidity in the room 101 can be detected. In the first embodiment, the first humidity sensor 81 is installed in each room 101 near the duct that communicates the inside of each room 101 with the outside air supply device 31 . The second humidity sensor 82 is a sensor that detects the absolute humidity of the outside air. The installation position of the second humidity sensor 82 is arbitrary as long as the absolute humidity of the outside air can be detected. In the first embodiment, the second humidity sensor 82 is installed in the vicinity of the first suction port 51 inside the second housing 50 of the outside air supply device 31 . In the first embodiment, humidity means absolute humidity unless otherwise specified.

The control device 60 is composed of dedicated hardware or a CPU (Central Processing Unit) that executes a program stored in a memory. Note that the CPU is also called a central processing unit, a processing unit, an arithmetic unit, a microprocessor, a microcomputer, or a processor.

If the controller 60 is dedicated hardware, the controller 60 may be, for example, a single circuit, a composite circuit, an Application Specific Integrated Circuit (ASIC), a Field-Programmable Gate Array (FPGA), or a combination thereof. Applicable. Each functional unit implemented by the control device 60 may be implemented by separate hardware, or each functional unit may be implemented by one piece of hardware.

When the control device 60 is a CPU, each function executed by the control device 60 is implemented by software, firmware, or a combination of software and firmware. Software and firmware are written as programs and stored in memory. The CPU implements each function of the control device 60 by reading and executing the programs stored in the memory. Here, the memory is, for example, non-volatile or volatile semiconductor memory such as RAM, ROM, flash memory, EPROM or EEPROM.

A part of the functions of the control device 60 may be realized by dedicated hardware, and a part thereof may be realized by software or firmware.

The control device 60 according to Embodiment 1 includes an input unit 61, a first calculation unit 62, a second calculation unit 63, a third calculation unit 64, a control unit 65, and a storage unit 66 as functional units. .

The input unit 61 is a functional unit to which values detected by the first temperature sensor 71, the second temperature sensor 72, the temperature sensor 73, the first humidity sensor 81, and the second humidity sensor 82 are input. Operation modes of the indoor unit 11 and the outside air supply unit 31 are also input to the input unit 61 from a remote controller (not shown) or the like. The input unit 61 also receives the set temperature and set humidity in the room 101 .

The first computation unit 62 is a functional unit that computes a target evaporation temperature of the refrigerant flowing through the first heat exchanger 16 when the first heat exchanger 16 of the indoor unit 11 functions as an evaporator. The target evaporation temperature is a control target value when controlling the temperature of the refrigerant flowing through the first heat exchanger 16 . The second computing unit 63 is a functional unit that computes the target supply air temperature of the supply air supplied from the outside air supply device 31 into the room 101 . The target supply air temperature is a control target value when controlling the temperature of the supply air supplied from the outside air supplier 31 into the room 101 . The third computing unit 64 is a functional unit that computes a target water temperature of water flowing through the second heat exchanger 42 of the outside air supply device 31 . The target water temperature is a control target value when controlling the temperature of water flowing through the second heat exchanger 42 .

The control unit 65 is a functional unit that controls each component of the air conditioning system 100 based on the information input to the input unit 61 and the control target values and the like calculated by the respective calculation units. The storage unit 66 stores information input to the input unit 61, information used by each of the above-described calculation units when calculating the control target value, calculation results of each of the above-described calculation units, and information used by the control unit 65 for control. and the like.

Next, the operation of the air conditioning system 100 according to Embodiment 1 will be described. In addition, below, the operation|movement when the air conditioning system 100 performs cooling dehumidification operation is demonstrated.

When the air conditioning system 100 performs cooling and dehumidifying operation, the indoor unit 11 of the internal air conditioner 1 sucks the air in the room 101 into the first housing 11a. The indoor unit 11 of the internal air conditioner 1 cools the air sucked into the first housing 11a by the refrigerant flowing through the first heat exchanger 16 so that the temperature in the room 101 reaches the set temperature. The fresh air is supplied into the room 101 . Further, when the air conditioning system 100 performs the cooling and dehumidifying operation, the outside air supply device 31 of the outdoor air conditioner 2 sucks outside air into the second housing 50 . The outside air supply device 31 of the outdoor air conditioner 2 cools the outside air sucked into the second housing 50 by the water flowing through the second heat exchanger 42 so that the absolute humidity in the room 101 becomes the set humidity. The dehumidified and cooled outside air is supplied into the room 101 as supply air.

Here, the air conditioning system 100 according to Embodiment 1 adjusts the target evaporation temperature of the refrigerant flowing through the first heat exchanger 16 so that the air conditioning load of the internal air conditioner 1 becomes a load corresponding to the sensible heat load. It is determined as follows.

The first calculation unit 62 of the control device 60 of the air conditioning system 100 according to Embodiment 1 subtracts the set temperature in the room 101 stored in the storage unit 66 from the temperature detected by the first temperature sensor 71, A temperature difference ΔT is calculated. In other words, the first calculator 62 subtracts the set temperature in the room 101 from the temperature in the room 101 to calculate the temperature difference ΔT. Then, the first calculation unit 62 determines the target evaporation temperature Te_tgt of the refrigerant flowing through the first heat exchanger 16 according to the temperature difference ΔT.

Specifically, when the temperature difference ΔT is large, the sensible heat load is large. Therefore, a large amount of energy is required to cool the air sucked into the first housing 11 a of the indoor unit 11 . On the other hand, when the temperature difference ΔT is small, the sensible heat load is small. Therefore, the energy for cooling the air sucked into the first housing 11a of the indoor unit 11 may be small. Therefore, the first calculation unit 62 lowers the target evaporation temperature Te_tgt when the temperature difference ΔT is large, and raises the target evaporation temperature Te_tgt when the temperature difference ΔT is small. That is, in the air-conditioning system 100 according to Embodiment 1, the state in which the temperature difference ΔT is the first temperature difference is defined as the first temperature difference state, and the second temperature difference state in which the temperature difference ΔT is smaller than the first temperature difference is defined as the first temperature difference state. When the state with the temperature difference is the second temperature difference state, the temperature of the refrigerant flowing through the first heat exchanger 16 in the second temperature difference state is the first heat exchange state in the first temperature difference state. higher than the temperature of the coolant flowing through the vessel 16.

Note that when a plurality of first temperature sensors 71 are installed in one room 101 , the first calculation unit 62 calculates the temperature difference ΔT for the temperatures detected by all the first temperature sensors 71 . Then, the first calculation unit 62 determines the target evaporation temperature Te_tgt of the refrigerant flowing through the first heat exchanger 16 using the largest temperature difference ΔT. Further, when a plurality of indoor units 11 are installed in one room 101 and a set temperature is set for each indoor unit 11, the first calculation unit 62 calculates the temperature Calculate the difference ΔT. Then, the first calculation unit 62 determines the target evaporation temperature Te_tgt of the refrigerant flowing through the first heat exchanger 16 using the largest temperature difference ΔT. Further, when a plurality of indoor units 11 are installed in one room 101 and the first temperature sensor 71 is provided for each indoor unit 11, the first calculation unit 62 calculates ΔT for each indoor unit 11. . Then, the first calculation unit 62 determines the target evaporation temperature Te_tgt of the refrigerant flowing through the first heat exchanger 16 using the largest temperature difference ΔT. By determining the target evaporating temperature Te_tgt in this way, it is possible to prevent the internal air conditioner 1 from becoming inadequate with respect to the sensible heat load.

Specifically, in Embodiment 1, the first calculation unit 62 determines the target evaporation temperature Te_tgt as follows.

FIG. 5 is a diagram for explaining a method of determining the target evaporation temperature of refrigerant flowing through the first heat exchanger in the air conditioning system according to Embodiment 1 of the present invention. Note that the horizontal axis of FIG. 5 represents the temperature difference ΔT, which is the value obtained by subtracting the set temperature in the room 101 from the temperature detected by the first temperature sensor 71 . The vertical axis of FIG. 5 is the target evaporation temperature Te_tgt of the refrigerant flowing through the first heat exchanger 16 .

The storage unit 66 of the control device 60 stores in advance an upper limit value Te_max of the target evaporation temperature Te_tgt and a lower limit value Te_min of the target evaporation temperature Te_tgt. Then, when the temperature difference ΔT<0, the first calculation unit 62 determines the target evaporation temperature Te_tgt to be the upper limit value Te_max. Further, when the temperature difference ΔT>ΔT1, the first calculation unit 62 sets the target evaporation temperature Te_tgt to the lower limit Te_min. Further, when 0≦temperature difference ΔT≦ΔT1, the first calculation unit 62 calculates the target evaporation temperature between the upper limit value Te_max and the lower limit value Te_min so that the target evaporation temperature Te_tgt increases as the temperature difference ΔT decreases. Determine Te_tgt. Note that ΔT1 is, for example, the allowable range of the temperature inside the room 101 with respect to the set temperature. ΔT1 may be stored in advance in the storage unit 66 as a fixed value, or may be a value stored in the storage unit 66 by the user via the input unit 61 .

In addition, the air-conditioning system 100 according to Embodiment 1 is configured such that the air-conditioning load of the outdoor air conditioner 2 is a load corresponding to the latent heat load. The supply air temperature is determined as follows.

The second calculation unit 63 of the control device 60 of the air conditioning system 100 according to Embodiment 1 subtracts the set humidity in the room 101 stored in the storage unit 66 from the humidity detected by the first humidity sensor 81, A humidity difference Δx is calculated. In other words, the second calculator 63 subtracts the set humidity in the room 101 from the absolute humidity in the room 101 to calculate the humidity difference Δx. Then, the second calculation unit 63 determines the target supply air temperature TSA_tgt of the supply air supplied from the outside air supply device 31 into the room 101 according to the humidity difference Δx.

Specifically, when the humidity difference Δx is large, the latent heat load is large. Therefore, it is necessary to cool the outside air sucked into the second housing 50 of the outside air supply device 31 to a lower temperature and remove more moisture from the outside air. On the other hand, when the humidity difference Δx is small, the latent heat load is small. Therefore, the amount of moisture removed by cooling the outside air sucked into the second housing 50 of the outside air supply device 31 may be small. Therefore, the second calculation unit 63 decreases the target supply air temperature TSA_tgt when the humidity difference Δx is large, and increases the target supply air temperature TSA_tgt when the humidity difference Δx is small. That is, in the air-conditioning system 100 according to Embodiment 1, a state in which the humidity difference Δx is the first humidity difference is defined as a first humidity difference state, and a second humidity difference state in which the humidity difference Δx is smaller than the first humidity difference. When the humidity difference state is defined as a second humidity difference state, the temperature of the supplied air supplied from the outside air supply device 31 into the room 101 in the second humidity difference state is the same as that in the first humidity difference state. is higher than the temperature of the supply air supplied from the outside air supply device 31 into the room 101 .

In addition, when a plurality of first humidity sensors 81 are installed in one room 101 , the second calculation unit 63 calculates the humidity difference Δx for the humidity detected by all the first humidity sensors 81 . Then, the second calculation unit 63 determines the target supply air temperature TSA_tgt of the supply air supplied from the outside air supply device 31 into the room 101 using the humidity difference Δx having the largest value. Moreover, when supplying air to a plurality of rooms 101 by one outside air supply device 31 , the second calculation unit 63 calculates the humidity difference Δx for all the rooms 101 . Then, the second calculation unit 63 determines the target supply air temperature TSA_tgt of the supply air supplied from the outside air supply device 31 into the room 101 using the humidity difference Δx having the largest value.

Specifically, in Embodiment 1, the second calculation unit 63 determines the target supply air temperature TSA_tgt as follows.

FIG. 6 is a diagram for explaining a method of determining a target supply air temperature of supply air supplied from an outside air supplier into a room in the air conditioning system according to Embodiment 1 of the present invention. Note that the horizontal axis of FIG. 6 represents the humidity difference Δx, which is the value obtained by subtracting the set humidity in the room 101 from the humidity detected by the first humidity sensor 81 . The vertical axis in FIG. 6 is the target supply air temperature TSA_tgt of the supply air supplied into the room 101 from the outside air supply device 31 .

The storage unit 66 of the controller 60 stores in advance an upper limit value TSA_max of the target supply air temperature TSA_tgt and a lower limit value TSA_min of the target supply air temperature TSA_tgt. Then, when the humidity difference Δx<0, the second calculation unit 63 determines the target supply air temperature TSA_tgt to be the upper limit value TSA_max. Further, when the humidity difference Δx>Δx1, the second calculation unit 63 determines the target supply air temperature TSA_tgt to be the lower limit value TSA_min. Further, when 0≦humidity difference Δx≦Δx1, the second calculation unit 63 calculates the target supply air temperature TSA_tgt between the upper limit value TSA_max and the lower limit value TSA_min so that the target supply air temperature TSA_tgt increases as the humidity difference Δx decreases. Determine the air temperature TSA_tgt. Note that Δx1 is, for example, the allowable range of humidity in the room 101 with respect to the set humidity. Δx1 may be stored in the storage unit 66 in advance as a fixed value, or may be a value stored in the storage unit 66 by the user via the input unit 61 .

By determining the target evaporation temperature Te_tgt of the refrigerant flowing through the first heat exchanger 16 as described above, the air conditioning load of the internal air conditioner 1 becomes a load corresponding to the sensible heat load. Further, by determining the target supply air temperature TSA_tgt of the supply air supplied into the room 101 from the outside air supplier 31 as described above, the air conditioning load of the outdoor air conditioner 2 becomes a load corresponding to the latent heat load. Therefore, the air conditioning system 100 according to Embodiment 1 can reduce the power consumption of the air conditioning system 100 as a whole.

Here, in a state where the target evaporation temperature Te_tgt of the refrigerant flowing through the first heat exchanger 16 is the lower limit value Te_min, the state where the temperature difference ΔT exceeds the preset threshold value ΔT_max continues for a preset time or more. Suppose. In this case, the second calculation unit 63 sets the target supply air temperature TSA_tgt of the supply air supplied from the outside air supplier 31 into the room 101 to the lower limit value TSA_min. In other words, when the temperature difference ΔT exceeds the first threshold value for the first specified time or more, in the air-conditioning system 100 according to Embodiment 1, the temperature of the air supplied from the outside air supplier 31 into the room 101 is goes down. By increasing the sensible heat processing capacity of the outdoor air conditioner 2 in this way, it is possible to prevent the air conditioning system 100 from becoming insufficient in capacity with respect to the sensible heat load.

Further, a state in which the humidity difference Δx exceeds a preset threshold value Δx_max in a state where the target supply air temperature TSA_tgt of the supply air supplied from the outside air supply device 31 into the room 101 is the lower limit value TSA_min is set in advance. It is assumed that it is continuous for more than the specified time. In this case, the first calculation unit 62 sets the target evaporation temperature Te_tgt of the refrigerant flowing through the first heat exchanger 16 to the lower limit Te_min. In other words, when the humidity difference Δx exceeds the second threshold for the second specified time or longer, the temperature of the refrigerant flowing through the first heat exchanger 16 decreases. By increasing the latent heat processing capacity of the internal air conditioner 1 in this way, it is possible to prevent the air conditioning system 100 from becoming insufficient in capacity with respect to the latent heat load.

In the case where one outdoor air supply device 31 supplies air to a plurality of rooms 101 and different indoor units 11 are responsible for cooling each room 101, the second calculation unit 63 is handled by different indoor units 11. The humidity difference Δx is referred to for each room 101 . Then, in a certain room 101, it is assumed that the state in which the humidity difference Δx exceeds the threshold Δx_max continues for a preset time or longer. In this case, the first calculation unit 62 sets the target evaporation temperature Te_tgt of the indoor unit 11 responsible for cooling the room 101 to the lower limit Te_min. Moreover, when a plurality of first humidity sensors 81 are installed in one room 101 , the second calculation unit 63 calculates the humidity difference Δx for the humidity detected by all the first humidity sensors 81 . In this case, the humidity difference Δx with the largest value is used.

Further, in the air conditioning system 100 according to Embodiment 1, the temperature of the water flowing through the second heat exchanger 42 of the outside air supply device 31 is changed according to the outside air conditions, thereby further reducing power consumption.

Here, as a method of changing the temperature of the supplied air supplied from the outside air supplier 31 into the room 101, a method of changing the temperature of the water flowing through the second heat exchanger 42 of the outside air supplier 31 and a method of changing the temperature of the water flowing through the second heat exchanger 42 of the outside air supplier A method of changing the flow rate of water flowing to the second heat exchanger 42 of 31 is conceivable. In the case of the method of changing the temperature of the water flowing through the second heat exchanger 42 of the outside air supplier 31, the power consumption of the chiller 30 is reduced by increasing the temperature of the water flowing through the second heat exchanger 42 of the outside air supplier 31. can. Therefore, the power consumption of the air conditioning system 100 can be reduced. However, in order to actually vary the temperature of the water flowing through the second heat exchanger 42 of the outside air supply device 31, the water cooled by the water-refrigerant heat exchanger 36 of the chiller 30 must be supplied to the second heat exchanger 42. have to wait for it to arrive. Therefore, in the case of the method of changing the temperature of the water flowing through the second heat exchanger 42 of the outside air supply device 31 , the response rate is higher than that of the method of changing the flow rate of the water flowing through the second heat exchanger 42 of the outside air supply device 31 . is slow, and it is difficult to make the temperature of the air supplied from the outside air supplier 31 into the room 101 closely follow the target water temperature.

Therefore, in the air conditioning system 100 according to Embodiment 1, the temperature of the water flowing through the second heat exchanger 42 of the outside air supplier 31 is changed according to the outside air conditions, and then the temperature of the water flowing through the second heat exchanger 42 of the outside air supplier 31 is changed. 2 By changing the flow rate of the water flowing through the heat exchanger 42, the temperature of the supply air supplied from the outside air supply device 31 into the room 101 is changed. That is, in the air conditioning system 100 according to Embodiment 1, by changing the flow rate of the water flowing through the second heat exchanger 42 and the temperature of the water flowing through the second heat exchanger 42, the outside air supply device The temperature of the supply air supplied from 31 into the room 101 is changed. As a result, the temperature of the air supplied from the outside air supplier 31 into the room 101 can be made to closely follow the target water temperature, and the power consumption of the air conditioning system 100 can also be reduced.

FIG. 7 is a psychrometric diagram for explaining a method of determining the target water temperature of water flowing through the second heat exchanger in the air conditioning system according to Embodiment 1 of the present invention. The horizontal axis of FIG. 7 indicates the dry-bulb temperature, and the vertical axis of FIG. 7 indicates the absolute humidity.
The third calculation unit 64 of the control device 60 divides regions according to the outside air temperature and the outside air absolute humidity, for example, as shown in FIG. to decide. Specifically, the third computing unit 64 determines which region the outside air condition corresponds to based on the temperature of the outside air detected by the second temperature sensor 72 and the absolute humidity of the outside air detected by the second humidity sensor 82. to decide. Then, the third calculation unit 64 determines the target water temperature of the water flowing through the second heat exchanger 42 of the outside air supply device 31 based on the conditions of the relevant area.

The target water temperature in each area becomes lower in the area of the outside air condition where the air conditioning load becomes higher. For example, region A shown in FIG. 7 has a higher air conditioning load than region B shown in FIG. Therefore, the target water temperature for region A is lower than the target water temperature for region B. Similarly, region B shown in FIG. 7 has a higher air conditioning load than region C shown in FIG. Therefore, the target water temperature for region B is lower than the target water temperature for region C. In other words, when the state in which the outside air temperature is the first temperature is defined as the first temperature state, and the state in which the outside air temperature is at the second temperature lower than the first temperature is defined as the second temperature state, the second temperature state is defined as the second temperature state. The temperature of water flowing through the second heat exchanger 42 in the second temperature state is higher than the temperature of water flowing through the second heat exchanger 42 in the first temperature state. A state in which the absolute humidity of the outside air is the first absolute humidity is defined as a first humidity state, and a state in which the absolute humidity of the outside air is a second absolute humidity lower than the first absolute humidity is defined as a second humidity state. In this case, the temperature of water flowing through the second heat exchanger 42 in the second humidity state is higher than the temperature of water flowing through the second heat exchanger 42 in the first humidity state.

FIG. 8 is a psychrometric diagram for explaining a method of calculating a target water temperature of water flowing through the second heat exchanger in the air conditioning system according to Embodiment 1 of the present invention. The horizontal axis of FIG. 8 indicates the dry bulb temperature, and the vertical axis of FIG. 8 indicates the absolute humidity.
In each region, the air conditioning load is highest at the point where the outside air temperature and humidity are the highest in that region. In each zone, the temperature of the water flowing through the second heat exchanger 42 required to handle the air conditioning load in that zone will be lowest at the point where the outside air temperature and humidity are the highest in that zone. In each region, the temperature of the water flowing through the second heat exchanger 42 required to process the air conditioning load is set as the target water temperature of the water flowing through the second heat exchanger 42 . Note that the point where the outside air temperature and the outside air humidity are the highest in region B is point D shown in FIG. In addition, the point at which the outside air temperature and the outside air humidity are the highest in region C is point E shown in FIG.

A specific method of calculating the target water temperature of the water flowing through the second heat exchanger 42 will be described with reference to FIG. A point OA in FIG. 8 indicates the outside air environment at the time of calculating the target water temperature, for example. A point RA in FIG. 8 indicates the set temperature and set humidity in the room 101 . First, based on the outside air environment indicated by point OA, the set temperature and humidity in room 101 indicated by point RA, and the heat exchange efficiency of total heat exchanger 57, the amount of air flowing into second heat exchanger 42 is Compute the environment. The environment of the air flowing into the second heat exchanger 42 is point Coil_in in FIG. The environment here means temperature and absolute humidity.

Point SA in FIG. 8 indicates the target supply air temperature of the air supplied from the outside air supplier 31 into the room 101 and the target air temperature of the supply air supplied from the outside air supplier 31 into the room 101. is the absolute humidity of the case. A point Tw in FIG. 8 indicates the temperature of the water flowing through the second heat exchanger 42 necessary for processing the air conditioning load and the absolute humidity of the saturated air at that temperature. Δx2 shown in FIG. 8 is the difference between the absolute humidity at the point Coil_in and the absolute humidity at the point SA. Δx3 shown in FIG. 8 is the difference between the absolute humidity at the point Coil_in and the absolute humidity at the point Tw. After calculating the point Coil_in as described above, the point Tw is calculated based on the environment of the point Coil_in, the environment indicated by the point SA, and the condition that the ratio between Δx2 and Δx3 is constant. Then, the temperature of the point Tw is set as the target water temperature of the water flowing through the second heat exchanger 42 .

Finally, the control flow when the air conditioning system 100 performs cooling and dehumidifying operation will be described.

FIG. 9 is a diagram for explaining a control flow when the air-conditioning system according to Embodiment 1 of the present invention performs cooling and dehumidifying operation.
When the cooling and dehumidifying operation of the air conditioning system 100 is started, in step S1, the first calculation unit 62 subtracts the set temperature in the room 101 from the temperature detected by the first temperature sensor 71 to calculate the temperature difference ΔT. . Also, in step S1, the second calculation unit 63 subtracts the set humidity in the room 101 from the humidity detected by the first humidity sensor 81 to calculate the humidity difference Δx.

In step S2, the first calculation unit 62 determines the target evaporation temperature Te_tgt of the refrigerant flowing through the first heat exchanger 16 according to the temperature difference ΔT. Also, in step S2, the second calculation unit 63 determines the target supply air temperature TSA_tgt of the supply air supplied from the outside air supply device 31 into the room 101 according to the humidity difference Δx.

In step S3, the first calculation unit 62 determines whether or not the state in which the temperature difference ΔT exceeds the threshold ΔT_max continues for a preset time. If the state in which the temperature difference ΔT exceeds the threshold ΔT_max does not continue for the preset time, the process proceeds to step S5. On the other hand, when the state in which the temperature difference ΔT exceeds the threshold ΔT_max continues for the preset time, the second calculation unit 63 determines in step S4 the amount of air supplied from the outside air supply device 31 into the room 101. Change the target supply air temperature TSA_tgt to the lower limit value TSA_min.

In step S5, the second calculation unit 63 determines whether or not the state in which the humidity difference Δx exceeds a preset threshold value Δx_max continues for a preset time. If the state in which the humidity difference Δx exceeds the preset threshold Δx_max does not continue for the preset time, the process proceeds to step S7. On the other hand, if the state in which the humidity difference Δx exceeds the preset threshold value Δx_max continues for a preset time period, in step S6, the first calculation unit 62 determines the target amount of the refrigerant flowing through the first heat exchanger 16 The evaporation temperature Te_tgt is changed to the lower limit Te_min.

In step S<b>7 , the third calculation unit 64 determines the target water temperature Tw_tgt of the water flowing through the second heat exchanger 42 .

In step S8, the control unit 65 sets the temperature of the refrigerant flowing through the first heat exchanger 16 to the target evaporation temperature Te_tgt, and the temperature of the supply air supplied from the outside air supplier 31 into the room 101 to the target supply air temperature TSA_tgt. , controls each component of the air conditioning system 100 so that the temperature of the water flowing through the second heat exchanger 42 becomes the target water temperature Tw_tgt.

In step S9, the control device 60 determines whether or not a command to end the cooling and dehumidifying operation has been input. If the command to end the cooling and dehumidifying operation has not been input, the above steps S1 to S8 are repeated. On the other hand, if a command to end the cooling/dehumidifying operation has been input, the control flow for the cooling/dehumidifying operation ends.

As described above, the air conditioning system 100 according to Embodiment 1 includes the indoor unit 11, the outdoor air supply unit 31, the first temperature sensor 71 that detects the temperature in the room 101, and the absolute humidity in the room 101. A first humidity sensor 81 and a control device 60 that stores the set temperature and set humidity in the room 101 are provided. The indoor unit 11 has a first heat exchanger 16 and a first housing 11a that houses the first heat exchanger 16, and the refrigerant flowing through the first heat exchanger 16 is sucked into the first housing 11a. Cool the air in the room 101 . The outside air supply device 31 has a second heat exchanger 42 and a second housing 50 that houses the second heat exchanger 42 . The cooled outside air is cooled, and the cooled outside air is supplied into the room 101 as supply air. In the air-conditioning system 100 according to Embodiment 1, the state in which the temperature difference ΔT, which is the value obtained by subtracting the set temperature from the temperature in the room 101, is the first temperature difference is defined as the first temperature difference state. , the second temperature difference state is defined as a second temperature difference state in which the temperature difference ΔT is smaller than the first temperature difference. is higher than the temperature of the refrigerant flowing through the first heat exchanger 16 in the first temperature difference state. Further, in the air-conditioning system 100 according to Embodiment 1, the state in which the humidity difference Δx, which is the value obtained by subtracting the set humidity from the absolute humidity in the room 101, is the first humidity difference is the first humidity difference state. When the state in which the humidity difference Δx is the second humidity difference smaller than the first humidity difference is defined as the second humidity difference state, the supply air supplied from the outside air supply device 31 in the second humidity difference state is is higher than the temperature of the supply air supplied from the outside air supplier 31 in the first humidity difference state.

The internal air conditioner 1 mainly processes the sensible heat load, and the outdoor air conditioner 2 mainly processes the latent heat load. The temperature of the refrigerant flowing through the first heat exchanger 16 of the indoor unit 11 of the indoor unit 1 and the temperature of the supply air supplied from the outdoor air supply unit 31 of the outdoor unit 2 are changed as in the first embodiment. As a result, the air conditioning load of the internal air conditioner 1 can be adjusted to a load corresponding to the sensible heat load, and the air conditioning load of the external air conditioner 2 can be adjusted to a load corresponding to the latent heat load. Therefore, the air conditioning system 100 according to Embodiment 1 can reduce the power consumption of the air conditioning system 100 as a whole. Moreover, the air-conditioning system 100 according to Embodiment 1 does not require complicated modeling work and simulation work in advance. Therefore, the air-conditioning system 100 according to Embodiment 1 can also be produced with less trouble.

Embodiment 2.
The power consumption of the air conditioning system 100 can be further reduced by calculating the upper limit value TSA_max of the target supply air temperature TSA_tgt of the supply air supplied from the outside air supplier 31 into the room 101 as follows. In the second embodiment, items that are not particularly described are the same as those in the first embodiment, and the same reference numerals are used for the same functions and configurations as in the first embodiment.

FIG. 10 is a diagram showing a schematic configuration of an air conditioning system according to Embodiment 2 of the present invention. Moreover, FIG. 11 is a diagram showing a schematic configuration of an outside air supply device of an outside air conditioner in an air conditioning system according to Embodiment 2 of the present invention.

The air conditioning system 100 according to Embodiment 2 includes a temperature sensor 74 and a humidity sensor 83 . The temperature sensor 74 is a sensor that detects the temperature of air flowing into the second heat exchanger 42 . The humidity sensor 83 is a sensor that detects the absolute humidity of the air flowing into the second heat exchanger 42 . The temperature sensor 74 and the humidity sensor 83 are, for example, downstream of the total heat exchanger 57 in the second housing 50 of the outside air supply device 31 and upstream of the second heat exchanger 42 in the air flow. It is installed in a side position.

Further, the control device 60 of the air conditioning system 100 according to Embodiment 2 includes a fourth computing section 67 as a functional section. The fourth computing unit 67 is a functional unit that computes the upper limit value TSA_max of the target supply air temperature TSA_tgt of the supply air supplied from the outside air supplier 31 into the room 101 .

Next, a method for determining the upper limit value TSA_max of the target supply air temperature TSA_tgt of the supply air supplied from the outside air supplier 31 into the room 101 will be described.

FIG. 12 is a psychrometric diagram for explaining a method of determining the upper limit value of the target supply air temperature of the supply air supplied into the room from the outside air supply device in the air conditioning system according to Embodiment 2 of the present invention. be. The horizontal axis of FIG. 12 indicates the dry bulb temperature, and the vertical axis of FIG. 12 indicates the absolute humidity.

In the second embodiment, the second heat exchanger 42 of the outside air supply device 31 can process the ventilation latent heat load, which is the load for dehumidifying the outside air to the set humidity, among the latent heat loads. Determine the upper limit value TSA_max.

Specifically, the upper limit value TSA_max is obtained as follows. A point Coil_in in FIG. 8 indicates the environment of the air entering the second heat exchanger 42 . That is, point Coil_in in FIG. and A point RA in FIG. 8 indicates the set temperature and set humidity in the room 101 . A point Tw in FIG. 8 indicates the target water temperature Tw_tgt of the water flowing through the second heat exchanger 42 and the absolute humidity of the saturated air at the target water temperature Tw_tgt.

When determining the upper limit value TSA_max, first, a straight line connects the point Coil_in and the point Tw. Then, a point on the straight line that has the same humidity as the set humidity in the room 101 is obtained. The temperature at that point is the upper limit value TSA_max.

Therefore, the formula for calculating the upper limit value TSA_max is the following formula (1).
TSA_max=TCoil_in−(TCoil_in−Tw_tgt)×(xCoil_in−xRA_set)÷(xCoil_in−xw) (1)
Note that TCoil_in is the temperature at the point Coil_in. That is, TCoil_in is the temperature of the air flowing into the second heat exchanger 42 detected by the temperature sensor 74 . xCoil_in is the absolute humidity at point Coil_in. That is, xCoil_in is the absolute humidity of the air flowing into the second heat exchanger 42 detected by the humidity sensor 83 . xRA_set is the set humidity in the room 101 . xw is the absolute humidity of the saturated air at the target water temperature Tw_tgt.

By determining the upper limit value TSA_max as in the second embodiment, when the latent heat load is small and the target supply air temperature TSA_tgt of the supply air supplied from the outside air supplier 31 into the room 101 reaches the upper limit value TSA_max , the second heat exchanger 42 of the outside air supply device 31 processes the ventilation latent heat load, which is the load for dehumidifying the outside air to the set humidity, among the latent heat loads. In other words, in the air conditioning system 100 according to Embodiment 2, the maximum absolute humidity of the supplied air supplied from the outside air supplier 31 is the same as the set humidity.

As described above, in the air conditioning system 100 according to Embodiment 2, when the latent heat load is small, the second heat exchanger 42 of the outside air supplier 31 only needs to process the ventilation latent heat load. The target supply air temperature TSA_tgt of the supply air supplied into the room 101 can be set high. Therefore, by determining the upper limit value TSA_max as in the second embodiment, the power consumption of the air conditioning system 100 can be further reduced.

Reference Signs List 1 indoor unit 2 outdoor unit 10 outdoor unit 11 indoor unit 11a first housing 12 refrigerant circuit 13 compressor 14 outdoor heat exchanger 15 expansion valve 16 first heat exchanger 17 Four-way valve, 18 refrigerant pipe, 19 outdoor unit fan, 20 indoor unit fan, 30 chiller, 31 outside air supply device, 32 refrigerant circuit, 33 compressor, 34 refrigerant-air heat exchanger, 35 expansion valve, 36 water-refrigerant heat Exchanger, 37 four-way valve, 38 chiller fan, 40 water circuit, 41 pump, 42 second heat exchanger, 43 flow control mechanism, 44 bypass pipe, 45 three-way valve, 46 water pipe, 50 second housing, 51 second 1 suction port, 52 first outlet, 53 second suction port, 54 second outlet, 55 air supply fan, 56 exhaust fan, 57 total heat exchanger, 60 control device, 61 input section, 62 first Computing section 63 Second computing section 64 Third computing section 65 Control section 66 Storage section 67 Fourth computing section 71 First temperature sensor 72 Second temperature sensor 73 Temperature sensor 74 Temperature sensor 81 1st humidity sensor, 82 2nd humidity sensor, 83 humidity sensor, 100 air conditioning system, 101 room.

Claims (5)

It has a first heat exchanger and a first housing that houses the first heat exchanger, and cools the air in the air-conditioned space sucked into the first housing by the refrigerant flowing through the first heat exchanger. indoor unit and
having a second heat exchanger and a second housing that houses the second heat exchanger, and cooling outside air sucked into the second housing by water flowing through the second heat exchanger, and cooled an outside air supplier that supplies the outside air to the air-conditioned space as supply air;
a first temperature sensor that detects the temperature of the air-conditioned space;
a first humidity sensor that detects the absolute humidity of the air-conditioned space;
a control device that stores the set temperature and set humidity of the air-conditioned space;
with
A state in which the temperature difference, which is the value obtained by subtracting the set temperature from the temperature of the air-conditioned space, is a first temperature difference is defined as a first temperature difference state, and a second temperature difference in which the temperature difference is smaller than the first temperature difference. When the state with the temperature difference is the second temperature difference state,
The temperature of the refrigerant flowing through the first heat exchanger when in the second temperature difference state is higher than the temperature of the refrigerant flowing through the first heat exchanger when in the first temperature difference state,
A first humidity difference state is defined as a state in which a humidity difference obtained by subtracting the set humidity from the absolute humidity of the air-conditioned space is a first humidity difference state, and a first humidity difference state in which the humidity difference is smaller than the first humidity difference. When the state of two humidity differences is defined as the second humidity difference state,
The temperature of the supply air supplied from the outside air supplier in the second humidity difference state is higher than the temperature of the supply air supplied from the outside air supplier in the first humidity difference state. is the configuration ,
The air conditioning system , wherein the maximum absolute humidity of the supplied air supplied from the outside air supply device is the same as the set humidity . It has a first heat exchanger and a first housing that houses the first heat exchanger, and cools the air in the air-conditioned space sucked into the first housing by the refrigerant flowing through the first heat exchanger. indoor unit and
having a second heat exchanger and a second housing that houses the second heat exchanger, and cooling outside air sucked into the second housing by water flowing through the second heat exchanger, and cooled an outside air supplier that supplies the outside air to the air-conditioned space as supply air;
a first temperature sensor that detects the temperature of the air-conditioned space;
a first humidity sensor that detects the absolute humidity of the air-conditioned space;
a control device that stores the set temperature and set humidity of the air-conditioned space;
with
A state in which the temperature difference, which is the value obtained by subtracting the set temperature from the temperature of the air-conditioned space, is a first temperature difference is defined as a first temperature difference state, and a second temperature difference in which the temperature difference is smaller than the first temperature difference. When the state with the temperature difference is the second temperature difference state,
The temperature of the refrigerant flowing through the first heat exchanger when in the second temperature difference state is higher than the temperature of the refrigerant flowing through the first heat exchanger when in the first temperature difference state,
A first humidity difference state is defined as a state in which a humidity difference obtained by subtracting the set humidity from the absolute humidity of the air-conditioned space is a first humidity difference state, and a first humidity difference state in which the humidity difference is smaller than the first humidity difference. When the state of two humidity differences is defined as the second humidity difference state,
The temperature of the supply air supplied from the outside air supplier in the second humidity difference state is higher than the temperature of the supply air supplied from the outside air supplier in the first humidity difference state. is the configuration,
The air conditioning system is configured such that the temperature of the supplied air supplied from the outside air supply device is lowered when the temperature difference exceeds the first threshold value for a first specified time or longer. It has a first heat exchanger and a first housing that houses the first heat exchanger, and cools the air in the air-conditioned space sucked into the first housing by the refrigerant flowing through the first heat exchanger. indoor unit and
having a second heat exchanger and a second housing that houses the second heat exchanger, and cooling outside air sucked into the second housing by water flowing through the second heat exchanger, and cooled an outside air supplier that supplies the outside air to the air-conditioned space as supply air;
a first temperature sensor that detects the temperature of the air-conditioned space;
a first humidity sensor that detects the absolute humidity of the air-conditioned space;
a control device that stores the set temperature and set humidity of the air-conditioned space;
with
A state in which the temperature difference, which is the value obtained by subtracting the set temperature from the temperature of the air-conditioned space, is a first temperature difference is defined as a first temperature difference state, and a second temperature difference in which the temperature difference is smaller than the first temperature difference. When the state with the temperature difference is the second temperature difference state,
The temperature of the refrigerant flowing through the first heat exchanger when in the second temperature difference state is higher than the temperature of the refrigerant flowing through the first heat exchanger when in the first temperature difference state,
A first humidity difference state is defined as a state in which a humidity difference obtained by subtracting the set humidity from the absolute humidity of the air-conditioned space is a first humidity difference state, and a first humidity difference state in which the humidity difference is smaller than the first humidity difference. When the state of two humidity differences is defined as the second humidity difference state,
The temperature of the supply air supplied from the outside air supplier in the second humidity difference state is higher than the temperature of the supply air supplied from the outside air supplier in the first humidity difference state. is the configuration,
The air conditioning system is configured such that the temperature of the refrigerant flowing through the first heat exchanger is lowered when the humidity difference exceeds the second threshold for a second specified time or longer. a second temperature sensor that detects the temperature of the outside air;
a second humidity sensor that detects the absolute humidity of the outside air;
with
When the state in which the temperature of the outside air is a first temperature is defined as a first temperature state, and the state in which the temperature of the outside air is a second temperature lower than the first temperature is defined as a second temperature state,
the temperature of the water flowing through the second heat exchanger when in the second temperature state is higher than the temperature of the water flowing through the second heat exchanger when in the first temperature state;
A state in which the absolute humidity of the outside air is a first absolute humidity is defined as a first humidity state, and a state in which the absolute humidity of the outside air is a second absolute humidity lower than the first absolute humidity is defined as a second humidity state. and
The temperature of the water flowing through the second heat exchanger under the second humidity state is higher than the temperature of the water flowing through the second heat exchanger under the first humidity state. The air conditioning system according to any one of claims 1 to 3 . A flow rate adjustment mechanism that adjusts the flow rate of the water flowing through the second heat exchanger,
By changing the flow rate of the water flowing through the second heat exchanger and the temperature of the water flowing through the second heat exchanger, the temperature of the supply air supplied from the outside air supply is changed. The air conditioning system according to any one of claims 1 to 4, which is a configuration.

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