CN110637198B - Air conditioning system - Google Patents

Abstract

The invention discloses an air conditioning system. The control device (60) performs a control operation in which the control device (60) adjusts the cooling capacity of the indoor unit (30) of the air conditioner (20) as a latent heat engine and the cooling capacity of the indoor unit (50) of the air conditioner (40) as a sensible heat engine so that the current indoor temperature and humidity approach target values.

Description

Air conditioning system

Technical Field

The present invention relates to an air conditioning system.

Background

Air conditioning systems for conditioning a room have been known. Some of these air conditioning systems perform indoor dehumidification in addition to indoor cooling.

For example, an air conditioning system described in patent document 1 is configured to have a refrigerant circuit in which a compressor, an outdoor heat exchanger, an expansion valve, and an indoor heat exchanger are connected, and a refrigeration cycle is performed in the refrigerant circuit. In an air conditioning system, during an operation for dehumidifying the interior of a room, the evaporation temperature of an indoor heat exchanger is lowered. In this way, the air is cooled to a temperature lower than the dew point temperature in the indoor heat exchanger, and moisture in the air is condensed. As a result, indoor dehumidification is performed.

Patent document 1: japanese laid-open patent publication No. 9-14724

Disclosure of Invention

The technical problem to be solved by the invention

In the air conditioning system as described above, if the air is cooled excessively for the purpose of dehumidifying the air, the following problem occurs: the indoor temperature is lowered to deteriorate comfort, or the energy saving property is deteriorated due to excessive temperature cooling.

The present invention has been made to solve the above-mentioned problems. The purpose is as follows: provided is an air conditioning system which is excellent in energy saving performance and can maintain the indoor temperature and the indoor humidity within a target range.

Technical solution for solving technical problem

The first aspect of the present invention is an air conditioning system including a plurality of air conditioners 20 and 40 and a control device 60. The plurality of air conditioners 20, 40 each having an indoor unit 30, 50 and an outdoor unit 21, 41, the plurality of air conditioners 20, 40 each performing a refrigeration cycle independently and being subject to the same indoor space; the control device 60 controls the plurality of air conditioners 20 and 40. The control device 60 is configured to simultaneously operate the plurality of air conditioners 20 and 40, and in the simultaneous operation, at least one air conditioner 20 is controlled as a latent heat engine so that the indoor unit 30 of the one air conditioner 20 cools air to a dew point temperature or lower, and the other air conditioners 40 are controlled as heat generators so that the indoor units 50 of the other air conditioners 40 cool air to a temperature higher than the dew point temperature. The control device 60 also performs a control operation in which the control device 60 adjusts the cooling capacity of the indoor unit 30 of the air conditioner 20 as the latent heat engine and the cooling capacity of the indoor unit 50 of the air conditioner 40 as the sensible heat engine so that the current indoor temperature and humidity approach the target values.

In the first aspect of the invention, during the simultaneous operation, the indoor unit 30 of a part of the air conditioners 20 becomes a latent heat engine, and cools the air to below the dew point temperature. Meanwhile, the indoor unit 50 of the other air conditioner 40 becomes a sensible heat machine, and cools the air to a temperature higher than the dew point temperature. In this way, the latent heat and the sensible heat of the indoor space 11 to be subjected to the air conditioners 20 and 40 can be substantially handled separately, and energy saving can be improved.

In the simultaneous operation, the control device 60 adjusts the cooling capacities of the indoor units 30 and 50 of the air conditioners 20 and 40 so that the current indoor temperature and humidity approach the target values. The indoor temperature and humidity approach the target values, so the indoor comfort is also sufficient.

The second aspect of the invention is characterized in that, on the basis of the first aspect of the invention: in the control operation, the cooling capacities of the indoor units 30 and 50 of the respective air conditioners 20 and 40 are determined by the control device 60 based on at least the target value and the current indoor temperature and humidity.

In the second aspect of the invention, the controller 60 determines the cooling capacity of each of the indoor units 30 and 50 of the latent heat engine and the sensible heat engine, respectively, based on at least the target value and the current indoor temperature and humidity. That is, if the target value and the current indoor temperature and humidity are known, it is possible to determine which of the indoor units 30 and 50 of the latent heat engine and the sensible heat engine has the cooling capacity changed in which manner so that the indoor temperature and humidity approach the target value. Therefore, the control device 60 determines the cooling capacity of each of the indoor units 30 and 50 based on the determination.

The third aspect of the present invention is the second aspect of the present invention, wherein: in the control operation, the cooling capacities of the indoor units 30 and 50 of the respective air conditioners 20 and 40 are determined by the control device 60 based on the target values, the current indoor temperature and humidity, and the indoor temperature and humidity before a predetermined time from the current indoor temperature and humidity.

In the third aspect of the invention, the controller 60 determines the cooling capacity of each of the indoor units 30 and 50 of the latent heat engine and the heat engine based on the target value, the current indoor temperature and humidity, and the indoor temperature and humidity before a predetermined time from the current indoor temperature and humidity. That is, if these indices are used, it is possible to grasp how the indoor temperature and humidity have migrated, and as a result, it is possible to grasp what relationship the current temperature and humidity have been with respect to the target value. Therefore, based on these indices, it is possible to determine which of the indoor units 30 and 50 in the latent heat engine and the sensible heat engine has the better cooling capability changed in which manner. Therefore, the control device 60 determines the cooling capacity of each of the indoor units 30 and 50 based on the determination.

The fourth aspect of the invention is, in any one of the first to third aspect of the invention, characterized in that: the control device 60 causes the plurality of air conditioners 20 and 40 to perform the simultaneous operation when the indoor temperature and the indoor humidity fall within a predetermined temperature and humidity range including the target values, and causes the control device 60 to cause all the air conditioners 20 to perform a dehumidification operation when the indoor humidity exceeds a predetermined humidity above the temperature and humidity range, and during the dehumidification operation, the control device 60 controls all the air conditioners 20 so that the indoor units 30 of all the air conditioners 20 cool the air to a dew point temperature or lower.

In the fourth aspect of the invention, the simultaneous operation is performed when the indoor temperature and the indoor humidity fall within the range of the predetermined temperature and humidity including the target values. Therefore, in the simultaneous operation, the indoor temperature and the indoor humidity can be brought close to the target values while the energy saving performance is ensured. On the other hand, when the humidity in the room exceeds a predetermined humidity due to an increase in latent heat load in the room, the dehumidification operation is performed so that the indoor units 30 and 50 of all the air conditioners 20 and 40 cool the air to the dew-point temperature or lower. This makes it possible to quickly deal with the humidity in the room and quickly ensure the comfort in the room.

The fifth invention is characterized in that, in any one of the first to fourth inventions, the: the control device 60 controls the cooling capacity of the indoor unit 30 of the air conditioner 20 as the latent heat engine and the cooling capacity of the indoor unit 50 of the air conditioner 40 as the sensible heat engine at the same time during the control operation.

In the fifth aspect of the invention, in the simultaneous operation, the cooling capacities of the latent heat engine and the sensible heat engine are controlled at the same timing. For example, if the cooling capacities of the two are changed at different timings, the temperature and humidity in the room fluctuate, and the temperature and humidity in the room cannot reach the target values. In contrast, by controlling the cooling capacities of the latent heat engine and the sensible heat engine at the same time, the attainment of the indoor temperature and humidity to the target value is improved.

Effects of the invention

According to the present invention, since the air is cooled to the dew point temperature or lower by the latent heat engine and the air is cooled to the temperature higher than the dew point temperature by the sensible heat engine in the simultaneous operation, the air in the room can be prevented from being excessively cooled, and the energy saving performance can be improved. In addition, in the simultaneous operation, the cooling capacities of the latent heat engine and the sensible heat engine are respectively adjusted so that the indoor temperature and humidity approach the target values. Therefore, the indoor temperature and the indoor humidity can be maintained within the target ranges, and the indoor comfort can be ensured.

Drawings

Fig. 1 is a schematic diagram of the overall configuration of an air conditioning system according to an embodiment.

Fig. 2 is a schematic diagram of duct systems of a first air conditioner and a second air conditioner in the air conditioning system according to the embodiment.

Fig. 3 is a block diagram of an air conditioning system according to an embodiment.

Fig. 4 is a flowchart for explaining a flow when the air conditioning system according to the embodiment shifts to the temperature/humidity control mode.

Fig. 5 is a flowchart for explaining the flow of the determination operation of each operation in the temperature/humidity control mode of the air conditioning system according to the embodiment.

Fig. 6 is an air line diagram for explaining the relationship between the threshold value or the region used in the first determination operation at the start of the temperature/humidity control mode and each operation.

Fig. 7 is an air line diagram for explaining the relationship between the threshold value or the region used in the determination operation at the time of the dehumidification operation and the non-separation operation and each operation.

Fig. 8 is an air line diagram for explaining the relationship between the threshold value or region used in the determination operation at the time of the hidden behind display separation operation and each operation.

Fig. 9 is an air line diagram for explaining the relationship between the threshold value or region used in the determination operation at the time of sensible heat operation and each operation.

Fig. 10 is an air line diagram for explaining the relationship between the threshold value or region used in the determination operation at the time of latent heat operation and each operation.

Fig. 11 is an air line diagram for explaining an evaporation temperature determining operation in the dehumidification operation and the latent heat operation.

Fig. 12 is an air line diagram for explaining a plurality of divided regions in the hidden-display separation operation.

FIG. 13 is a schematic flow chart of the step control of the underline separation operation.

Fig. 14 is a table showing an example of how the target evaporation temperature steps of the latent heat engine and the sensible heat engine are changed according to the current area and the previous area where the air state point is located.

Fig. 15 is a diagram for explaining the target evaporation temperatures of the latent heat engine and the sensible heat engine and the change width thereof.

Detailed Description

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. The following embodiments are essentially preferred examples, and are not intended to limit the scope of the present invention, its application, or its use.

Integral structure of air conditioning system

The air conditioning system 10 of the present embodiment includes a plurality of air conditioners 20 and 40. The plurality of air conditioners 20 and 40 air-condition the same indoor space 11. The air conditioning system 10 of the present embodiment is provided with two air conditioners (a first air conditioner 20 and a second air conditioner 40). The air conditioning system 10 may include three or more air conditioners. The first air conditioner 20 has the same basic structure as the second air conditioner 40. The air conditioning system 10 further includes a control device 60 for controlling each of the air conditioners 20 and 40.

First air conditioner

As shown in fig. 1 and 2, the first air conditioner 20 includes a first outdoor unit 21 installed outdoors and a plurality of first indoor units 30 installed indoors. The plurality of first indoor units 30 are connected in parallel to the first outdoor unit 21 via two connection pipes. The number of the first indoor units 30 may be one, two, or three or more.

The first air conditioner 20 includes a first refrigerant circuit 22 to be filled with refrigerant. The first refrigerant circuit 22 performs a refrigeration cycle by circulating a refrigerant. The first refrigerant circuit 22 is connected to a first compressor 23, a first outdoor heat exchanger 24, a first outdoor expansion valve 25, a first four-way selector valve 26, and a plurality of first indoor heat exchangers 32.

The first compressor 23, the first outdoor heat exchanger 24, the first outdoor expansion valve 25, and the first four-way selector valve 26 are provided in the first outdoor unit 21. The first compressor 23 is constituted by an inverter type compressor with a variable capacity. The first compressor 23 is configured to be capable of adjusting the operating frequency (the rotational speed of the motor) by controlling the output of the inverter device. The first outdoor heat exchanger 24 is, for example, a tube-fin heat exchanger. A first outdoor fan 27 is provided in the vicinity of the first outdoor heat exchanger 24. In the first outdoor heat exchanger 24, the outdoor air sent from the first outdoor fan 27 exchanges heat with the refrigerant. The first outdoor expansion valve 25 is constituted by an electronic expansion valve whose opening degree is variable. The first four-way selector valve 26 has first to fourth ports. The first valve port communicates with the discharge side of the first compressor 23, and the second valve port communicates with the suction side of the first compressor 23. The third port communicates with the gas-side end of the first outdoor heat exchanger 24, and the fourth port communicates with the gas-side end of the first indoor heat exchanger 32. The first four-way selector valve 26 is switched between a first state (shown by solid lines in fig. 2) in which the first port communicates with the third port and the second port communicates with the fourth port, and a second state (shown by broken lines in fig. 2) in which the first port communicates with the fourth port and the second port communicates with the third port.

Each of the first indoor heat exchangers 32 is provided in each of the first indoor units 30. The first indoor heat exchanger 32 is disposed in an air passage in the first indoor unit 30. A first indoor fan 33 is provided near (downstream of) the first indoor heat exchanger 32. The indoor air (intake air) taken in from the indoor space 11 exchanges heat with the refrigerant in the first indoor heat exchanger 32. The air heat-exchanged in the first indoor heat exchanger 32 is supplied to the indoor space 11 as blown air.

The first indoor fan 33 is, for example, a centrifugal fan, and is configured to be capable of adjusting the fan air volume. The air volume of the first indoor fan 33 of the present embodiment can be switched among three stages, i.e., L-stage (small air volume), M-stage (medium air volume), and H-stage (large air volume).

Each of the first indoor units 30 is provided with a first intake temperature sensor 34 and a first intake humidity sensor 35. The first intake temperature sensor 34 detects the temperature of the intake air. The first intake humidity sensor 35 detects the humidity (absolute humidity) of the intake air.

In the first refrigerant circuit 22, a first refrigeration cycle (refrigeration cycle) and a second refrigeration cycle (heating cycle) are performed in a switched manner. In the first refrigeration cycle, the first four-way selector valve 26 is in the first position, and the first compressor 23, the first outdoor fan 27, and the first indoor fan 33 are operated. In the first refrigeration cycle, the refrigerant releases heat (condenses) in the first outdoor heat exchanger 24, is reduced in pressure by the first outdoor expansion valve 25, and then evaporates in the first indoor heat exchanger 32. In the second refrigeration cycle, the first four-way selector valve 26 is in the second position, and the first compressor 23, the first outdoor fan 27, and the first indoor fan 33 are operated. In this way, in the second refrigeration cycle, the refrigerant releases heat (condenses) in the first indoor heat exchanger 32, is reduced in pressure by the first outdoor expansion valve 25, and then evaporates in the first outdoor heat exchanger 24.

A refrigerant temperature sensor (not shown) that detects the evaporation temperature Te is provided in the first indoor heat exchanger 32 of the first refrigerant circuit 22.

Second air conditioner

As shown in fig. 2, the second air conditioner 40 includes the same constituent devices as the first air conditioner 20. That is, in the second air conditioner 40, the second outdoor unit 41 and the plurality of second indoor units 50 are connected together to form the second refrigerant circuit 42 in which the refrigerant circulates.

The second outdoor unit 41 is provided with a second compressor 43, a second outdoor heat exchanger 44, a second outdoor expansion valve 45, a second four-way selector valve 46, and a second outdoor fan 47. The second indoor unit 50 is provided with a second indoor heat exchanger 52, a second indoor fan 53, a second intake temperature sensor 54, and a second intake humidity sensor 55. As with the first refrigerant circuit 22, the second refrigerant circuit 42 performs a first refrigeration cycle (refrigeration cycle) and a second refrigeration cycle (heating cycle) in a switched manner. The configuration of each device of the second air conditioner 40 is the same as that of the first air conditioner 20, and therefore, the detailed description thereof is omitted.

Remote controller

As shown in fig. 1, the first air conditioner 20 is equipped with a first remote controller 36. The second air conditioner 40 is equipped with a second remote controller 56. The remote controllers 36 and 56 are installed on, for example, an indoor wall, and are configured to be operable by a user. Each of the remote controllers 36 and 56 is provided with an operation unit for turning on/off the power supply of the corresponding air conditioner 20 or 40, switching the operation mode, switching the direction of the blown air, and the like. Each of the remote controllers 36 and 56 is provided with a display unit for displaying the current operation mode, set temperature, set humidity, and the like of the corresponding air conditioner 20 or 40.

Control device

As shown in fig. 1 and 3, the air conditioning system 10 includes a control device 60 (control system) for controlling each of the air conditioners 20 and 40. The control device 60 of the present embodiment includes a first local controller 61, a second local controller 71, a communication terminal 80, a router 85, and a cloud server 90.

The first local controller 61 is provided for the first air conditioner 20. The first local controller 61 is configured to be able to control each component of the first refrigerant circuit 22, the first indoor fan 33, and the like. The first local controller 61 is configured by a microcomputer and a storage device (specifically, a semiconductor memory) storing software for operating the microcomputer.

The first local controller 61 includes a first capability decision section 62, a first capability control section 63, and a first communication section 64. The first capacity determining unit 62 is a calculation unit for determining the capacity of the first air conditioner 20. The first capacity control unit 63 is a control unit for controlling the capacity of the first air conditioner 20.

The first communication unit 64 is connected to the internet 86 via the router 85, and is configured to be able to communicate with the cloud server 90 via the internet 86. The communication between the first communication unit 64 and the router 85 may be realized by a wired method or may be realized by a wireless method. According to the structure, the

The first local controller 61 and the cloud server 90 can exchange signals such as an operation command and a control parameter in both directions.

The second local controller 71 is provided for the second air conditioner 40. The second local controller 71 is configured to be able to control the respective constituent devices of the second refrigerant circuit 42, the second indoor fan 53, and the like. The second local controller 71 is constituted by a microcomputer and a storage device (specifically, a semiconductor memory) storing software for operating the microcomputer.

The second local controller 71 includes a second capability determining section 72, a second capability control section 73, and

and a second communication unit 74. The second capacity determining unit 72 is a computing unit for determining the capacity of the second air conditioner 40. The second capacity control unit 73 is a control unit for controlling the capacity of the second air conditioner 40.

The second communication unit 74 is connected to the internet 86 via the router 85, and is configured to be able to communicate with the cloud server 90 via the internet 86. The communication between the second communication unit 74 and the router 85 may be realized by a wired method or may be realized by a wireless method.

The communication terminal 80 is a communication device that a user issues a command to perform an operation in a temperature/humidity control mode described in detail later. The communication terminal 80 is configured by, for example, a smartphone, a tablet PC, or the like. The communication terminal 80 has a microcomputer and a storage device (specifically, a semiconductor memory) storing software for operating the microcomputer. The communication terminal 80 includes a touch panel 81 serving as both a display unit and an operation unit, and a communication unit 82 connected to a cloud server 90 via the internet 86.

A program (control application program) for executing the temperature/humidity control mode is stored in the communication terminal 80. The user can switch the temperature/humidity control mode on/off, set the indoor target temperature Ts in the temperature/humidity control mode, and set the indoor target humidity Rs in the temperature/humidity control mode by operating the touch panel 81 of the communication terminal 80.

The cloud server 90 is configured to be capable of bi-directionally communicating with the first local controller 61, the second local controller 71, and the communication terminal 80 via the internet 86. The cloud server 90 has a microcomputer and a storage device (specifically, a semiconductor memory) storing software for operating the microcomputer.

The cloud server 90 includes an operation determination unit 91 and a capability determination unit 92. The operation determination unit 91 performs a determination operation for switching various operations (described in detail later) in the temperature/humidity control mode. The capacity determination unit 92 determines the target evaporation temperature of each air conditioner 20, 40 and the speed (fan stage) of the indoor fan in each operation in the temperature/humidity control mode. The cloud server 90 transmits the operation parameters thus obtained to the local controllers 61 and 71 via the internet 86 at predetermined time intervals (for example, 20 seconds).

Working conditions-

The operation of the air conditioning system 10 will be described in detail.

In the air conditioning system 10, a temperature control mode and a temperature and humidity control mode are selectable. The temperature control mode is an operation mode for adjusting only the air temperature in the indoor space 11, and includes a cooling operation and a heating operation. In the temperature control mode, control is performed to bring the temperature of the indoor air close to a target value. The temperature/humidity control mode is an operation mode for adjusting the temperature and humidity of the indoor air in the indoor space 11. The temperature and humidity control mode includes 1) dehumidification operation, 2) non-divisional operation, 3) latent sensible-division operation, 4) sensible-heat operation, and 5) latent-heat operation. In the temperature/humidity control mode, the operations 1) to 5) are automatically switched according to the air state (temperature and humidity) in the room. These operations will be described in detail later.

-cooling operation in temperature control mode

The cooling operation in the temperature control mode will be described. In the cooling operation, the first refrigeration cycle described above is performed in each of the air conditioners 20 and 40. That is, the refrigerant compressed by the compressors 23 and 43 is condensed by the outdoor heat exchangers 24 and 44, and releases heat to the outdoor air. The condensed refrigerant is decompressed by the outdoor expansion valves 25 and 45, and then flows through the indoor heat exchangers 32 and 52. In each of the indoor heat exchangers 32 and 52, the refrigerant absorbs heat from the indoor air and evaporates. In this way, the intake air is cooled in each of the indoor units 30 and 50. The evaporated refrigerant is sucked into the compressors 23 and 43 and compressed again. The air cooled by each of the indoor heat exchangers 32 and 52 is supplied to the indoor space 11 as blown air.

During the cooling operation, the capacities of the air conditioners 20 and 40 are controlled according to the difference Δ T between the temperature of the intake air of the indoor units 30 and 50 and the set temperature. When the Δ T is increased, the target evaporation temperature of each air conditioner 20, 40 is decreased, and the operating frequency of each compressor 23, 43 is increased. Conversely, when Δ T is smaller, the target evaporation temperature of each air conditioner 20, 40 becomes larger, and the operating frequency of each compressor 23, 43 becomes smaller.

-temperature and humidity control mode-

The operation in the temperature/humidity control mode is an operation in which the indoor temperature is brought close to the target temperature Ts and the indoor humidity is brought close to the target humidity Rs. In the temperature/humidity control mode, the various operations are switched so that the current indoor temperature/humidity approaches the target point S (see fig. 6) according to the current air state point C. The temperature/humidity control mode is realized by the mutual signal transmission and reception among the local controllers 61 and 71, the cloud server 90, and the communication terminal 80. The transmission and reception of signals between these terminals are performed at predetermined time intervals (for example, 20 seconds).

Control before transition to temperature/humidity control mode

The control before the transition to the temperature/humidity control mode will be described with reference to fig. 4. When the user starts an application program of the communication terminal 80 and selects "on" of the "temperature and humidity control mode" on the touch panel 81, the signal is output to the cloud server 90. At the same time, the target temperature Ts and the target humidity Rs set at the communication terminal 80 are input to the cloud server 90. As described above, when the temperature/humidity control mode is instructed to start, the process proceeds from step St1 to step St 2.

Next, the cloud server 90 transmits the received target temperature Ts and target humidity Rs to the local controllers 61 and 71 of the air conditioners 20 and 40, or the remote controllers 36 and 56. Each local controller 61, 71 uses the intake air temperature detected by each air conditioner 20, 40 and the target temperature Ts to determine whether each air conditioner 20, 40 is activated (activated by temperature: thermo on). The local controllers 61 and 71 may determine whether or not the air conditioners 20 and 40 are activated, using the intake air humidity and the target humidity Rs detected by the air conditioners 20 and 40.

As described above, when the temperature-dependent start condition is satisfied, the process proceeds from step St2 to step St3, that is, to the temperature/humidity control mode.

First judgment action

As shown in fig. 5, when the temperature/humidity control mode is shifted, the first determination operation is performed (step St 51). In the first determination operation, the operation determination unit 91 determines which of the 1) dehumidification operation, 3) sensible heat operation, 4) sensible heat operation, and 5) latent heat operation is performed. That is, in the first determination operation, the 2) non-division operation is not selected. In the determination operation, the target temperature Ts set in the communication terminal 80, the target humidity Rs set in the communication terminal 80, and the current air state of the indoor space 11 are used. Here, as the index indicating the current air state, the current air temperature T of the indoor space 11, the current air humidity R of the indoor space 11, and the current discomfort index DI of the indoor space 11 are used.

The air temperature T uses the highest air temperature Tmax among the respective detected temperatures of the plurality of first intake temperature sensors 34 and the respective detected temperatures of the plurality of second intake temperature sensors 54. The air humidity R is a detected humidity corresponding to the maximum air temperature Tmax among the detected humidities of the plurality of first intake humidity sensors 35 and the detected humidities of the plurality of second intake humidity sensors 55. That is, the air temperature T and the air humidity R correspond to the pair of the suction temperature sensors 34, 54 and the suction humidity sensors 35, 55 of the same indoor unit 30, 50.

The discomfort index DI is determined from the air temperature T and the air humidity R. Here, the discomfort index (disconfort index) is one of the warm indexes indicating the sensation of warmth of the human body, and can be obtained by a relational expression including temperature and humidity.

In the determination operation, a plurality of thresholds for determining the transition state of each operation are used. These thresholds are determined based on target values of the air state in the room (i.e., target temperature Ts and target humidity Rs).

Specifically, conceptually described using the air line diagram of fig. 6, the operation determination unit 91 calculates the first temperature threshold value Ts1, the second temperature threshold value Ts2, the third temperature threshold value Ts3, the fourth temperature threshold value Ts4, and the stop (thermal off) determination temperature Toff based on the target temperature Ts. The first temperature threshold value Ts1 is a value obtained by adding a predetermined temperature Δ t1 (e.g., 0.5 ℃) to the target temperature Ts. The second temperature threshold value Ts2 is a value obtained by adding a predetermined temperature Δ t2 (e.g., 1.5 ℃) to the target temperature Ts. The third temperature threshold value Ts3 is a value obtained by adding a predetermined temperature Δ t3 (e.g., 2.0 ℃) to the target temperature Ts. The fourth temperature threshold value Ts4 is a value obtained by subtracting the predetermined temperature Δ t4 (e.g., 0.5 ℃) from the target temperature Ts. The stop determination temperature Toff is a value obtained by subtracting a predetermined temperature (for example, 2 ℃) from the target temperature. In the present embodiment, Δ t1 is equal to Δ t 4.

The operation determination unit 91 calculates the first humidity threshold Rs1, the second humidity threshold Rs2, the third humidity threshold Rs3, and the fourth humidity threshold Rs4 based on the target humidity Rs. Here, the first humidity threshold Rs1 is a value obtained by adding a predetermined humidity Δ r1 (for example, 1.0g/kg (dry air)) to the target humidity Rs. The second humidity threshold Rs2 is a value obtained by adding a predetermined humidity Δ r2 (for example, 2.0g/kg (dry air)) to the target humidity Rs. The third humidity threshold Rs3 is a value obtained by subtracting a predetermined humidity Δ r3 (e.g., 1.0g/kg (dry air)) from the target humidity Rs. The fourth humidity threshold Rs4 is a value obtained by subtracting a predetermined humidity Δ r4 (for example, 2.0g/kg (dry air)) from the target humidity Rs. In the present embodiment, Δ r1 is equal to Δ r3, and Δ r2 is equal to Δ r 4.

The operation determination unit 91 calculates a target discomfort index (target discomfort index DIs1) as the target of the indoor space 11, based on the target temperature Ts and the target humidity Rs. In the psychrometric chart of fig. 6, the discomfort index becomes larger toward the upper right (the higher the temperature and humidity are); the discomfort index becomes smaller the further to the lower left (the lower the temperature and humidity). Therefore, in the psychrometric chart, the target discomfort index Ds1 becomes a line extending to the upper left, and the target discomfort index DIs1 becomes the first discomfort index threshold value. The operation determination unit 91 sets a value obtained by adding a predetermined value (for example, 0.5) to the target discomfort index DIs1 as the second discomfort index threshold value DIs 2.

The operation determination unit 91 compares each of the above thresholds with the current air state point C (i.e., the air temperature T and the air humidity R) to determine which operation to shift to.

Specifically, when the current air state point C is within the area E1 surrounded by the thick line, the operation determination unit 91 determines to shift to the hidden-display separation operation. That is, when the air temperature T is lower than the second temperature threshold Ts2, the air humidity R is equal to or higher than the third humidity threshold Rs3, and the air humidity R is lower than the first humidity threshold Rs1, the transition to the dive-display separation operation is determined. Further, the operation determination unit 91 determines to shift to the hidden-display separation operation also when the current discomfort index DI of the air is lower than the target discomfort index DIs1 and the air humidity R is equal to or higher than the third humidity threshold Rs 3.

When the current air state point C is within the area E2 surrounded by the thick line, the operation determination unit 91 determines to shift to sensible heat operation. That is, when the air temperature T is equal to or higher than the second temperature threshold value Ts2 and the air humidity R is lower than the first humidity threshold value Rs1, the sensible heat operation is determined. The operation determination unit 91 also determines to shift to sensible heat operation when the air temperature T is lower than the second temperature threshold Ts2 and the air humidity R is lower than the third humidity threshold Rs 3.

When the current air state point C is within the area E3 surrounded by the thick line, the operation determination unit 91 determines to shift to the latent heat operation. That is, when the air temperature T is lower than the first temperature threshold Ts1, the air humidity R is equal to or higher than the first humidity threshold Rs1, and the discomfort index DI is equal to or higher than the target discomfort index DIs1, the transition to the latent heat operation is determined.

When the current air state point C is within the area E4, the operation determination unit 91 determines to shift to the dehumidification operation. That is, when the air temperature T is equal to or higher than the first temperature threshold Ts1 and the air humidity R is equal to or higher than the first humidity threshold Rs1, the transition to the dehumidification operation is determined.

As shown in fig. 5, in the present embodiment, when a predetermined time (for example, 120 seconds) has elapsed after the start of the dehumidification operation at step St56, the operation shifts to step St57, and the dehumidification operation is switched to the non-separated operation.

Outline of the second and subsequent judgment actions

In the second and subsequent determination operations (step St58) after the transition to the temperature/humidity control mode, the operation determination unit 91 determines which of the operations (2) other than the dehumidification operation (non-divided operation), 3) sensible heat operation, 4) sensible heat operation, and 5) latent heat operation) is performed. That is, in the temperature/humidity control mode, in the first determination operation immediately after the start of the temperature/humidity control mode, the dehumidification operation is performed only when the current air is in the area E4.

In each operation, the second and subsequent determination operations are performed once every predetermined time (for example, every 20 seconds). The basic determination criterion in the second and subsequent determination operations is the same as in the first determination operation. However, in the second and subsequent determination operations, the threshold for determining the next operation based on the current operation type is different from the first determination operation.

Judgment action in dehumidification operation/non-separation operation

Fig. 7 shows threshold values of the determination operation in the dehumidification operation and the non-separation operation. In these operations, the humidity range of the region E1 corresponding to the latent image separation operation is expanded downward (low humidity side) compared to other determination operations, and a detailed description thereof will be omitted. In addition, in these operations, in the region E1 corresponding to the latent image separation operation, there is no threshold value of the discomfort index in the range of the first humidity threshold Rs1 or more.

Judgment action in separate operation of diving display

The threshold value of the determination operation in the hidden display separation operation is shown in fig. 8. In the latent sensible heat separation operation, the region E2 corresponding to sensible heat operation and the region E3 corresponding to latent heat operation are smaller than the first determination operation, and a detailed description thereof will be omitted. In the sneak display separation operation, when the current air state point C is in the region E5, the transition to the non-separation operation is determined. The range of the region E5 in the latent image separation operation is smaller than the region E4 in the first determination operation (transition range to the dehumidification operation). In this way, in the determination operation in the hidden behind separate operation, the area E1 for continuing the hidden behind separate operation is larger than the area E1 of the first determination operation. Therefore, after a certain operation is shifted to the latency separation operation, the air temperature T and the air humidity R are slightly increased, so that the other operation can be prevented from being returned again (so-called hunting).

Judging action of sensible heat running

The threshold value of the determination operation in the sensible heat operation is shown in fig. 9. In the sensible heat operation, there is an area E6 (hatched area) which is not in the other determination operation, and a detailed description thereof will be omitted. The region E6 is a region for determining transition to the non-split operation, similarly to the region E5. However, in the determination operation during sensible heat operation, when the state point C of air is in the region E5, the operation is quickly shifted to the non-separate operation, whereas when the state point C of air is in the region E6, the operation is shifted to the non-separate operation after the state continues for a predetermined time (e.g., 180 seconds). In this way, by increasing the time constraint in the region near the boundary from the sensible heat operation to the non-separated operation, the fluctuation between the sensible heat operation and the non-separated operation can be avoided.

Judging action of latent heat operation

Fig. 10 shows threshold values of the determination operation in the latent heat operation. In the latent heat operation, the range of the humidity of the region E1 corresponding to the latent heat separation operation is expanded to the lower side (low humidity side) than the first determination operation, and a detailed description thereof is omitted.

Overview of operations

Next, each operation performed in the temperature/humidity control mode will be described. The operation in the temperature and humidity control mode is roughly divided into: all of the plurality of air conditioners 20, 40 become the first operation of the latent heat engine; a second operation in which a part of the plurality of air conditioners (the first air conditioner 20 in this example) becomes a latent heat engine and the other air conditioners (the second air conditioner 40 in this example) become heat generators; and a third operation in which all of the plurality of air conditioners 20 and 40 (in this example, the first air conditioner 20 and the second air conditioner 40) become heat generators. The dehumidifying operation, the non-separating operation and the latent heat operation are included in the first operation. The latent heat split operation corresponds to the second operation, and the sensible heat operation corresponds to the third operation.

The "latent heat engine" is an air conditioner that controls the indoor heat exchangers 32, 52 of the indoor units 30, 50 so as to cool air to a dew point temperature or lower. Therefore, if the air is cooled in the indoor units 30 and 50 of the latent heat engine, moisture in the air is condensed, and the condensed water is collected in a drain pan or the like. Thus, in the indoor units 30 and 50 of the latent heat machine, both the temperature and the humidity of the air are reduced.

The "heat development machine" is an air conditioner that controls the indoor heat exchangers 32 and 52 of the indoor units 30 and 50 so as to cool air to a temperature higher than the dew-point temperature. Therefore, if the air is cooled in the indoor units 30 and 50 of the sensible heat unit, moisture in the air does not condense, and only the temperature of the air decreases.

Dehumidification operation

The dehumidification operation is an operation of rapidly lowering the absolute humidity in the room under a condition of high indoor humidity and high indoor temperature. In the dehumidifying operation, both the first air conditioner 20 and the second air conditioner 40 become latent heat engines.

When shifting to the dehumidification operation, the cloud server 90 transmits a signal for controlling the air volume of the indoor fans 33 and 53 of the air conditioners 20 and 40 to the local controllers 61 and 71. During the dehumidification operation, a signal for controlling the air volumes of the indoor fans 33 and 53 to the L range is transmitted. Thus, during the dehumidification operation, the air volumes of all the indoor fans 33 and 53 are small, and the dehumidification performance of each of the indoor units 30 and 50 is improved.

The cloud server 90 appropriately obtains the target evaporation temperature TeS of each air conditioner 20, 40, and transmits the obtained target evaporation temperature TeS to each local controller 61, 71. Here, in the dehumidification operation, the target evaporation temperature TeS is calculated based on the current air state by the following processing (target evaporation temperature determination processing). Specifically, the capacity determination unit 92 calculates the target evaporation temperature TeS using the functional expression stored in the memory. Here, the functional formula is a function including the saturation curve shown on the air line graph of fig. 11, the current air temperature T, and the current air humidity R. Specifically, as shown in fig. 11, the functional expression is a functional expression for determining a temperature Tp corresponding to a tangent point P of a saturation curve on the air line graph and a straight line M passing through the current state point of the air. Here, the current air state point C corresponds to the current air temperature T and the current air humidity R. The temperature Tp corresponding to the tangent point P is calculated from the functional expression, and is set as the target evaporation temperature TeS. In the dehumidification operation, in principle, such a target evaporation temperature determination process is executed once every predetermined time (20 seconds).

The target evaporation temperature TeS thus obtained is appropriately transmitted to each local controller 61, 71 via the internet 86. As a result, each of the air conditioners 20 and 40 controls the operating frequency of the compressors 23 and 43 so that the current evaporation temperature Te approaches the target evaporation temperature TeS received at predetermined time intervals.

By thus determining the target evaporation temperature T during the dehumidification operation, it is possible to prevent the target evaporation temperature TeS from becoming excessively high or excessively low. When the target evaporation temperature TeS is too high, the temperature of the coolable air increases, and the amount of moisture that can be condensed from the air also decreases. Therefore, the indoor air cannot be dehumidified quickly, and the indoor temperature and humidity cannot be brought close to the target point S quickly. As a result, the comfort of the indoor space 11 is impaired.

On the other hand, if the target evaporation temperature TeS is too low, the air tends to be dehumidified in a region where sensible heat of the air is relatively large (a region where the inclination of the arrow a in fig. 11 is small). In this region, the ratio of the latent heat to be handled to the total heat to be handled becomes small, and therefore, conditions unfavorable for dehumidification are created. Therefore, when the air is cooled in this area, the dehumidification efficiency is lowered, and the energy saving property is deteriorated.

In contrast, as shown in fig. 11, by setting the temperature Tp corresponding to the tangent point P to the target evaporation temperature TeS, the target evaporation temperature TeS does not become too high or too low. As a result, both the comfort in the room and the energy saving performance of the air conditioning system 10 can be achieved.

The upper limit value is set for the target evaporation temperature TeS determined in the dehumidification operation so that the air can be reliably cooled to the dew point temperature or lower in each latent heat machine. Therefore, the air cooled by each latent heat machine during the dehumidification operation is not higher than the dew point temperature.

In the dehumidification operation, as described above, the target evaporation temperature determination process is performed in principle once every predetermined time (20 seconds). However, in order to protect the compressors 23, 43 or to prevent the evaporation temperature Te from fluctuating, the next update determination is performed before each target evaporation temperature determination process is executed.

In the update determination, it is determined whether or not the target evaporation temperature process is executed again. In the update determination, when either or both of the condition 1-a and the condition 1-B are satisfied, the target evaporation temperature determination process is performed to update the target evaporation temperature TeS.

1-A: e1 with the current absolute Te-TeS absolute less than or equal to

1-B: e2 is less than or equal to (current | Te-TeS | -last | Te-TeS |) |

Here, the current | Te — TeS | is an absolute value of a difference between the current evaporation temperature Te and the current target evaporation temperature TeS. The previous | Te-TeS | corresponds to | Te-TeS | calculated before the current update judgment, i.e., in the previous update judgment. E1 and E2 are predetermined judgment thresholds.

When the condition 1-a is satisfied, it can be determined that the actual evaporation temperature Te is close to the target evaporation temperature TeS. Therefore, when the condition 1-a is satisfied, the target evaporation temperature determination process is performed again, and the target evaporation temperature TeS is recalculated.

When the condition 1-B is satisfied, it can be determined that the amount of change in the decrease in the difference between the evaporation temperature Te and the target evaporation temperature TeS is small, and the evaporation temperature Te tends to approach the target evaporation temperature TeS. Therefore, even when the condition 1-B is satisfied, the target evaporation temperature determination process is performed again, and the target evaporation temperature TeS is recalculated.

When neither the condition 1-a nor the condition 1-B is satisfied, it can be determined that the evaporation temperature Te does not approach the target evaporation temperature TeS, and the evaporation temperature Te changes greatly. Therefore, when these conditions are not satisfied, the target evaporation temperature determination process is prohibited, and the target evaporation temperature TeS is not recalculated. Thus, when the evaporation temperature Te changes greatly, the target evaporation temperature TeS can be restricted from being changed again. Therefore, it is possible to avoid a large change in the operating frequency of the compressors 23, 43 or a fluctuation in the evaporation temperature Te.

Non-separating operation

The non-separated operation is an operation of lowering the absolute humidity in the room under a condition of high indoor humidity and high indoor temperature, as in the dehumidification operation. In the non-split operation, both the first air conditioner 20 and the second air conditioner 40 become latent heat engines. However, as described above, the non-separation operation is not performed in the first determination operation (see fig. 5). In the non-split operation, both the first air conditioner 20 and the second air conditioner 40 become latent heat engines.

When shifting to the non-separated operation, the cloud server 90 transmits a signal for controlling the air volume of the indoor fans 33 and 53 of the air conditioners 20 and 40 to the local controllers 61 and 71, respectively. In the non-separate operation, a signal for controlling the air volume of the indoor fans 33 and 53 to the M level is transmitted. Thus, during the non-separated operation, the air volumes of all the indoor fans 33 and 53 are equal to the medium air volume.

The cloud server 90 appropriately obtains the target evaporation temperature TeS of each air conditioner 20, 40, and transmits the obtained target evaporation temperature TeS to each local controller 61, 71. Here, the target evaporation temperature TeS of the non-divided operation is determined by a method similar to the cooling operation in the temperature control mode.

That is, in the evaporation temperature determination process of the non-separated operation, the target evaporation temperature TeS is calculated from the difference Δ Trs between the current air temperature T and the target temperature Ts set in the communication terminal 80. When Δ Trs becomes large, the target evaporation temperature TeS is lowered to increase the capacity of each air conditioner 20, 40. Conversely, when Δ Trs is small, the target evaporation temperature TeS is increased to lower the capacity of each air conditioner 20, 40.

The upper limit value is set for the target evaporation temperature TeS determined in the non-divided operation so that the air can be reliably cooled to the dew point temperature or lower in each latent heat machine. Therefore, the air cooled by each latent heat machine in the non-split operation is not higher than the dew point temperature.

As in the dehumidification operation, whether or not the target evaporation temperature TeS is updated is determined in the non-divided operation. In this way, the compressors 23, 43 can be protected, and fluctuations in the evaporation temperature Te can be avoided.

Latent heat operation

The latent heat operation is an operation for lowering the absolute humidity in the room under a condition of high indoor humidity. In the latent heat operation, both the first air conditioner 20 and the second air conditioner 40 become latent heat engines. The control of the latent heat operation is basically the same as the dehumidifying operation.

During the latent heat operation, a signal for controlling the air volume of the indoor fans 33 and 53 to the M range is transmitted. Thus, during the latent heat operation, the air flow rates of all the indoor fans 33 and 53 become the medium air flow rates.

In the evaporation temperature determination process of the latent heat operation, as in the dehumidification operation, the target evaporation temperature TeS is determined based on the temperature Tp corresponding to the above-described tangent point P. However, unlike the dehumidification operation, the target evaporation temperature TeS is not updated in the latent heat operation. Therefore, in the latent heat operation, the target evaporation temperature TeS must be recalculated at predetermined time intervals (for example, 20 seconds).

As described above, the latent heat operation is performed in the case where the state point C of the air is in the region E3, and the region E3 is located near the region where the operation is stopped according to the temperature. Assuming that recalculation of the target evaporation temperature TeS is prohibited in the latent heat operation as in the dehumidification operation, the air may be excessively cooled during this period, and the air temperature T may be much lower than the target evaporation temperature TeS. In this case, the air temperature T may also reach a region where the temperature stops.

In contrast, in the present embodiment, the target evaporation temperature TeS needs to be updated during the latent heat operation. Therefore, the target evaporation temperature TeS can be adjusted before the air temperature T is excessively cooled. This also avoids the air temperature T reaching the temperature-dependent stop region. In the latent heat operation, the evaporation temperature Te tends to approach the target evaporation temperature TeS more easily than in the dehumidification operation. Therefore, even if the update determination is limited, the operating frequency and the evaporation temperature Te of the compressors 23 and 43 do not change greatly.

Overview of dive-show separated operation

The latent heat and sensible heat separate operation (simultaneous operation) is an operation in which latent heat and sensible heat in the room are individually handled by the air conditioners 20 and 40 when the indoor temperature and the indoor humidity are in the range close to the target point S. In the latent heat and display separation operation of the present embodiment, the first air conditioner 20 becomes a latent heat engine, and the second air conditioner 40 becomes a heat display engine. Therefore, in the stealth-defined operation, the air is cooled and dehumidified by the indoor units 30 and 50 of the first air conditioner 20, and only the air is cooled by the indoor units 30 and 50 of the second air conditioner 40. By enabling the latent heat engine and the sensible heat engine to operate simultaneously, the indoor temperature can be prevented from excessively dropping, and the indoor temperature and humidity can be close to the target range.

In the latent display separation operation, it is necessary to send different control signals from the cloud server 90 to the local controller (the first local controller 61 in this example) provided to the latent heat engine and the local controller (the second local controller 71 in this example) provided to the latent heat engine, respectively. This is because the sensible heat machine and the latent heat machine are controlled differently. Therefore, the cloud server 90 registers therein the facility information indicating which air conditioner 20, 40 is the latent heat engine and which air conditioner 20, 40 is the heat engine when the latent heat display separation operation is performed. In this example, the equipment information indicating that the first air conditioner 20 becomes a latent heat engine and the equipment information indicating that the second air conditioner 40 becomes a heat engine in the latent heat display separation operation are registered in the cloud server 90. For example, such information is transmitted from the communication terminal 80 and the local controllers 61 and 71 to the cloud server 90 via the internet 86.

Control of submersible heat engine in operation with separate display

In the latent display separation operation, the cloud server 90 transmits a signal for controlling the air volume of the first indoor fan 33 to the first local controller 61 equipped to the first air conditioner 20 as a latent heat engine. In the hidden display separate operation, the air volume of the first indoor fan 33 of the first air conditioner 20 is switched between two stages (for example, two stages of the L stage and the M stage). The first indoor fan 33 may be switched between two ranges, i.e., an M range and an H range.

In addition, the cloud server 90 transmits a target evaporation temperature (first target evaporation temperature TeS1) for controlling the evaporation temperature Te of the first air conditioner 20 to the first local controller 61.

The evaporation temperature of the latent heat engine in the latent heat separation operation is determined by a method similar to the dehumidification operation. Specifically, the capacity determination unit 92 sets the temperature corresponding to the tangent point of the saturation curve on the air line graph and the straight line passing through the target point S as the first target evaporation temperature TeS 1. That is, in the dehumidification operation, the current state point C of the air (i.e., the air temperature T and the air humidity R) is used when the tangent point to the saturation curve is obtained, whereas in the latent image separation operation, the target point S (i.e., the target temperature Ts and the target humidity Rs) is used, and both are different from each other. Since the target point S is determined by the set value of the communication terminal 80, it does not substantially change as in the state point C. Therefore, by finding the tangent point based on the target point S, the first target evaporation temperature TeS1 does not change greatly. Therefore, the current state point C of the air can be prevented from coming out of the region E1 in fig. 8 due to the change in the first target evaporation temperature TeS1, and switching from the hidden-display separation operation to another operation can be suppressed.

As in the dehumidification operation, the update determination is performed in the evaporation temperature determination process of the latent heat engine that operates in the latent display separation mode. By so doing, the compressors 23, 43 can be protected, and fluctuations in the evaporation temperature Te can be prevented.

In the latent image separation operation, the first target evaporation temperature TeS1 of the latent heat engine is adjusted in stages based on the current state point C of the air, the target point S, and the change that has just occurred in the state point C of the air (the air temperature T and the air humidity R), and a detailed description thereof will be omitted.

Control of heat-displaying machine in separate operation of latent display

In the hidden display separate operation, the cloud server 90 sends a signal for controlling the air volume of the second indoor fan 53 to the second local controller 71 equipped to the second air conditioner 40 as the display unit. In the hidden display separate operation, the air volume of the second indoor fan 53 of the second air conditioner 40 is controlled to, for example, M range or H range.

The cloud server 90 transmits a target evaporation temperature TeS (a second target evaporation temperature TeS2) for controlling the evaporation temperature Te of the second air conditioner 40 to the second local controller 71.

In the evaporation temperature determination process of the sensible heat engine in the latent sensible separation operation, the second target evaporation temperature TeS2 is determined so that the air processed by the sensible heat engine is higher than the dew point temperature. Specifically, the dew point temperature Tdew-S corresponding to the air is calculated based on the state point (target temperature Ts and target humidity Rs) of the air corresponding to the current target point S. That is, the dew point temperature Tdew-S is a temperature at which dew water is generated from the air in the case where the air at the target point S has been cooled. In the evaporation temperature determination process, the dew point temperature Tdew-s is set to the second target evaporation temperature TeS 2.

When the current air state point C is in the area E1 including the target point S, the dive-display separation operation is performed. Therefore, the temperature and humidity of the air do not greatly differ from the target point S at the current air state point C. In addition, the air cooled by the second indoor heat exchanger 52 of the sensible heat engine is substantially impossible to be cooled to a temperature below the evaporating temperature. Therefore, by setting the dew point temperature Tdew-S corresponding to the target point S to the second target evaporation temperature TeS2, the air is substantially cooled to a temperature higher than the actual dew point temperature in the heat generator.

Here, the target point S is determined by a setting value of the communication terminal 80. The target point S is substantially unchanged as is the state point C. Therefore, by finding the dew point temperature based on the target point S, the second target evaporation temperature TeS2 does not change greatly. Thus, the current state point C of the air can be prevented from coming out of the region E1 in fig. 8 due to the change in the second target evaporation temperature TeS2, and the switching from the hidden behind display separated operation to another operation can be suppressed.

Sensible heat operation

The sensible heat operation is an operation in which the indoor temperature is lowered under a condition that the indoor temperature is high. In the sensible heat operation, both the first air conditioner 20 and the second air conditioner 40 become sensible heat machines.

When the sensible heat operation is shifted, the cloud server 90 transmits a signal for controlling the air volume of the indoor fans 33 and 53 of the air conditioners 20 and 40 to the local controllers 61 and 71. In the sensible heat operation, a signal for controlling the air volume of the indoor fans 33 and 53 to the M range is transmitted. Thus, during sensible heat operation, the air flow rates of all the indoor fans 33 and 53 become medium air flow rates.

In addition, the cloud server 90 transmits the target evaporation temperature TeS for controlling the evaporation temperature Te of each air conditioner 20, 40 to each local controller 61, 71.

In the evaporation temperature determination process of the latent image display operation, the target evaporation temperature TeS is determined so that the air processed by the sensible heat engine is higher than the dew point temperature. Specifically, the dew point temperature Tdew-C corresponding to the air is calculated from the current air state point C (air temperature T and air humidity R). That is, the dew point temperature Tdew-c is a temperature at which dew water is generated from the air in a case where the air at the current state point has been cooled. In the evaporation temperature determination process, the dew point temperature Tdew-c is set to the second target evaporation temperature TeS 2.

When the current air state point C is in the area E2 deviated from the target point S, sensible heat operation is performed. Therefore, the temperature of the current state point C of the air is higher than the temperature of the target point S. Therefore, in the sensible heat operation, unlike the control of the latent heat engine in the latent heat display separate operation, the dew point temperature Tdew-C corresponding to the target point S is set to the target evaporation temperature TeS, instead of the dew point temperature Tdew-C corresponding to the current state point C of the air. That is, when the dew point temperature Tdew-S corresponding to the target point S is set as the target evaporation temperature during the sensible heat operation, the target evaporation temperature TeS becomes too low, and the air may be cooled to the actual dew point temperature or less. On the other hand, since the dew-point temperature Tdew-C corresponding to the current state point C of the air is set as the target evaporation temperature TeS during the sensible heat operation, the air can be reliably prevented from being dehumidified during the sensible heat operation.

Stop action

In each of the above-described operations, in principle, when the temperature detected by each of the suction temperature sensors 34 and 54 of each of the air conditioners 20 and 40 becomes equal to or lower than the stop determination temperature Toff, the corresponding indoor unit 30 or 50 is stopped in accordance with the temperature.

However, in the latent image separation operation, the stop of all the indoor units 30 and 50 according to the temperature is prohibited until the detected temperature of all the intake temperature sensors 34 and 54 of at least the plurality of operating indoor units 30 and 50 becomes equal to or lower than the stop determination temperature Toff. Therefore, even if the temperatures detected by the suction temperature sensors 34, 54 of only some of the indoor units 30, 50 become equal to or lower than the stop determination temperature Toff during the stealth split operation, the indoor units 30, 50 do not stop according to the temperatures.

In the latent heat separation operation, the temperature of the blow air of the sensible heat engine and the latent heat engine is different. Therefore, temperature unevenness is likely to occur in the indoor space 11, and the detection temperature of the suction temperature sensors 34 and 54 of some of the indoor units 30 and 50 becomes extremely low due to the temperature unevenness, and the latent image separation operation may not be continued. On the other hand, by performing the above-described determination of the stop according to the temperature, the operation of the sneak display separation can be continued until the temperature of the entire indoor space 11 becomes equal to or lower than the stop determination temperature.

Details of step control of the underdisplay split operation

In the latent image separation operation, as described above, the first target evaporation temperature TeS1 of the first air conditioner 20 as the latent image generator and the second target evaporation temperature TeS2 of the second air conditioner 40 as the image generator are obtained. In the latent image separation operation, control is performed to increase and decrease the target evaporation temperatures TeS in stages based on the target evaporation temperatures TeS determined in this way. This control operation (step control) will be described with reference to fig. 12 to 14.

In step St21 of fig. 13, after the first target evaporation temperature TeS1 and the second target evaporation temperature TeS2 are determined by the above-described method, the process proceeds to steps St22 to St 24. In steps St22 to St24, it is determined in what range the current temperature and humidity of the air (state point C) is.

Specifically, the cloud server 90 stores data such as a function and a map for determining a plurality of areas (divided areas) shown in fig. 12. Here, in the example of fig. 12, a plurality of divided regions are formed in a lattice shape. In the present embodiment, an area E where the target point S exists and a plurality of (eight in the present example) areas A, B, C, D, F, G, H, I surrounding the area E are formed. These areas are determined based on a target temperature and humidity (target point S) set in the communication terminal 80. Therefore, if the position of the target point S changes, the positions of the respective areas on the air line graph also change.

More specifically, the region a is a range from the first temperature threshold Ts1 to the third temperature threshold Ts3 and from the first humidity threshold Rs1 to the second humidity threshold Rs 2. The region B is in the range above the first temperature threshold Ts1 up to the third temperature threshold Ts3, and in the range above the third humidity threshold Rs3 up to the first humidity threshold Rs 1. The region C is in the range above the first temperature threshold Ts1 to the third temperature threshold Ts3, and in the range above the fourth humidity threshold Rs4 to the third humidity threshold Rs 3. The region D is in the range above the fourth temperature threshold Ts4 up to the first temperature threshold Ts1 and in the range above the first humidity threshold Rs1 up to the second humidity threshold Rs 2. The region E is in the range above the fourth temperature threshold Ts4 up to the first temperature threshold Ts1 and in the range above the third humidity threshold Rs3 up to the first humidity threshold Rs 1. The region F is in the range above the fourth temperature threshold Ts4 to the first temperature threshold Ts1, and in the range above the fourth humidity threshold Rs4 to the third humidity threshold Rs 3. The region G is in the range from above the stop determination temperature Toff to the fourth temperature threshold Ts4, and is in the range from above the first humidity threshold Rs1 to the second humidity threshold Rs 2. The region H is in the range from the stop determination temperature Toff or higher to the fourth temperature threshold Ts4, and is in the range from the third humidity threshold Rs3 or higher to the first humidity threshold Rs 1. The region I is in the range from above the stop determination temperature Toff to the fourth temperature threshold Ts4, and is in the range from above the fourth humidity threshold Rs4 to the third humidity threshold Rs 3.

In steps St22 to St24, step control is performed to adjust the target evaporation temperature TeS of each air conditioner 20, 40 based on data indicating such a plurality of areas. In this step control, the target evaporation temperature TeS of the first air conditioner 20 as the latent heat engine and the target evaporation temperature TeS of the second air conditioner 40 as the sensible heat engine are changed based on the current state point C and the target point S of the air. In this step control, it is also considered which air state point C the current air state point C was at in the past.

Specifically, in step St22, the capability determining unit 92 of the control device 60 determines which of the plurality of divided regions the current air state point C is in. Next, in step St23, the capacity determining unit 92 of the control device 60 determines which of the plurality of divided areas the state point C of the previous air is located in. Here, the previous state point C of the air means the region determined at step St22 in the previous stage compared to the current stage in the present step control.

Next, in step St24, it is determined how to change the target evaporation temperatures TeS of the first air conditioner 20 and the second air conditioner 40 based on the current area determined in step St22 and the last area determined in step St 23. Specifically, in step St24, based on the current air state point C and the previous air state point C, a determination is made whether to increase the first target evaporation temperature TeS1 of the first air conditioner 20 by one step, maintain it unchanged, or decrease it by one step. At the same time, in step St24, based on the current air state point C and the previous air state point C, a determination is made whether to increase the second target evaporation temperature TeS2 of the second air conditioner 40 by one step, maintain it unchanged, or decrease it by one step.

Here, in the air conditioning system 10 of the present embodiment, the change width Δ Te1 (first change width) of each step of the first target evaporation temperature TeS1 on the latent heat machine side is set to, for example, 1.0 ℃. In addition, the change width Δ Te2 (second change width) of each step in the second target evaporation temperature TeS2 on the sensible heat machine side is set to, for example, 0.5 ℃. That is, in the latent display separation operation, the variation width Δ Te1 of the first target evaporation temperature TeS1 of the first air conditioner 20 as the latent heat engine is larger than the variation width Δ Te2 of the second target evaporation temperature TeS2 of the second air conditioner 40 as the heat engine. In other words, in the latent image separation operation, the width Δ W1 of change in the cooling capacity of the first air conditioner 20 as the latent image heat engine is larger than the width Δ W2 of change in the cooling capacity of the second air conditioner 40 as the image heat engine.

In step St24, the capacity of each air conditioner 20, 40 is determined based on the conditions shown in fig. 14, for example. Fig. 14 illustrates only some of the conditions. For example, as shown in condition E1 of fig. 14, it is assumed that the state point C of the current air is in the area E and the state point C of the last air is in the area a. This means that the air at the state point C in the region a migrates to the region E by the operation up to this point. When this condition is satisfied, the capacity determination unit 92 increases the first target evaporation temperature TeS1 of the latent heat engine by one step, while maintaining the second target evaporation temperature TeS2 of the sensible heat engine. Then, Δ Te1 is added to the current first target evaporation temperature TeS1, and the cooling capacity of the first air conditioner 20 is reduced. On the other hand, the current second target evaporation temperature TeS2 remains at the original value, and the cooling capacity of the second air conditioner 40 does not change. As described above, the temperature and humidity of the air having migrated to the area E can be suppressed from falling below the target point S.

For example, as shown in condition E2 of fig. 14, the current air state point C is in the area E, and the previous air state point C is in the area D. This means that the air at the state point C in the region D migrates to the region E by the operation up to this point. When this condition is satisfied, the capacity determination unit 92 increases the first target evaporation temperature TeS1 and the second target evaporation temperature TeS2 by one step. Then, Δ Te1 is added to the current first target evaporation temperature TeS1, and the cooling capacity of the first air conditioner 20 is reduced. Meanwhile, Δ Te2 is added to the current second target evaporation temperature TeS2, and the cooling capacity of the second air conditioner 40 decreases. As described above, the temperature and humidity of the air having migrated to the area E can be suppressed from falling below the target point S.

Similarly, as shown in condition E3 of fig. 14, when the current state point C of the air is in the region E and the last state point C of the air is in the region F, the first target evaporation temperature TeS1 is decreased by one step, and the second target evaporation temperature TeS2 is maintained. Thus, the cooling capacity of the first air conditioner 20 is increased, and the cooling capacity of the second air conditioner 40 is not changed.

Further, as shown in condition E4 of fig. 14, when the current air state point C is in the region E and the previous air state point is in the region I, the first target evaporation temperature TeS1 and the second target evaporation temperature TeS2 are decreased by one step, respectively. Thus, the cooling capacities of the first air conditioner 20 and the second air conditioner 40 are increased.

As shown in the condition a1 and the condition D1 in fig. 14, when the current air state point C is in the area a or the area D, it can be determined that the cooling capacity of each of the air conditioners 20 and 40 tends to be insufficient. Therefore, in this case, the first target evaporation temperature TeS1 and the second target evaporation temperature TeS2 are changed to the minimum values (the lowest step among the plurality of steps) regardless of which region the state point C of the previous air is located. Thus, the first target evaporation temperature TeS1 and the second target evaporation temperature TeS2 become minimum values, and the cooling capacities of the first air conditioner 20 and the second air conditioner 40 become large. Therefore, the state point C of the air can be made to quickly approach the region E.

As shown in condition I1 in fig. 14, when the current air state point C is in the region I, it can be determined that the cooling capacity of each air conditioner 20, 40 is excessive. Therefore, in this case, the first target evaporation temperature TeS1 is increased by one step regardless of the region in which the state point C of the previous air is located. Thus, the cooling capacity of the first air conditioner 20 is increased, and the state point C of the air can be quickly brought close to the region E.

The other condition determination will not be described.

In step St24, the target evaporation temperature TeS of each air conditioner 20, 40 is fine-adjusted in accordance with the area of the current air state point C and the area of the previous air state point C. That is, in step St24, the cooling capacity of each air conditioner 20, 40 is adjusted so that the current air state point C falls as much as possible in the area E based on the relationship between the current air state point C and the target point S and the relationship (trajectory) between the current air state point C and the previous air state point C. Thus, during the sneak display separation operation, the state point C of the air can be brought close to the target point S, and the indoor temperature and the indoor humidity can be maintained within the target ranges.

In step St24, after the target evaporation temperatures TeS of the air conditioners 20 and 40 are determined, the target evaporation temperatures TeS are transmitted to the local controllers 61 and 71. Therefore, the local controllers 61 and 71 adjust the operating frequencies of the compressors 23 and 43 so that the evaporation temperatures Te1 and Te2 of the air conditioners 20 and 40 approach the target evaporation temperatures TeS.

Next, in step St25, if the target temperature Ts and the target humidity Rs set at the communication terminal 80 have changed, the process proceeds to step St 21. In this case, the first target evaporation temperature Te1 and the second target evaporation temperature Te2 are recalculated based on the newly set target point S. Then, the determination processing of step St22 to step St24 is executed again. On the other hand, in step St25, if the target temperature Ts and the target humidity Rs are not changed, step S21 is skipped and the processing from step St22 to step St24 is repeatedly executed.

Variation range of step control

The range of change of the target evaporation temperature TeS in the step control will be described in more detail. As shown in fig. 15, in the latent heat display separation operation, the first target evaporation temperature TeS1 of the first air conditioner 20 as the latent heat engine becomes a temperature equal to or lower than the dew point temperature, and the second target evaporation temperature TeS2 of the second air conditioner 40 as the heat engine is higher than the dew point temperature. Therefore, the temperature difference between the intake air temperature of the first indoor unit 30 and the first target evaporation temperature TeS1 is greater than the temperature difference between the intake air temperature of the second indoor unit 50 and the second target evaporation temperature TeS 2. That is, in the stealth-separation operation, the cooling capacity of the air of the first indoor unit 30 is greater than the cooling capacity of the air of the second indoor unit 50.

On the other hand, in the latent image separation operation, as described above, the target evaporation temperature TeS is finely adjusted in stages in the first air conditioner 20 and the second air conditioner 40. Here, when the variation width Δ Te1 of the first target evaporation temperature TeS1 of the first air conditioner 20 is too small, the variation width Δ W1 of the cooling capacity of each step with respect to the cooling capacity to be possessed by the latent heat machine also becomes too small. As a result, the responsiveness of the cooling capacity of the latent heat engine deteriorates. In addition, when the variation width Δ Te2 of the second target evaporation temperature TeS2 of the second air conditioner 40 is too large, the variation width Δ W2 of the cooling capacity per step with respect to the cooling capacity required by the sensible heat engine also becomes too large. As a result, the cooling capacity of the heat developing machine cannot be adjusted with high accuracy.

In the present embodiment, the range Δ Te1 of change in the first target evaporation temperature TeS1 of the latent heat engine is made larger than the range Δ Te2 of change in the second target evaporation temperature TeS2 of the sensible heat engine. In other words, the variation width Δ W1 (first variation width) of the cooling capacity of the latent heat engine is made larger than the variation width Δ W2 (second variation width) of the cooling capacity of the sensible heat engine.

Specifically, in the present embodiment, the change width Δ Te1 of the first target evaporation temperature TeS1 of the latent heat engine is set to 1.0 ℃. Here, the modification width of 1.0 ℃ corresponds to the amount of change in the evaporation temperature required to change the absolute humidity of the air by 1.0/kg (da) under the rated operating conditions of the first indoor unit 30. In addition, the change width Δ Te2 of the second target evaporation temperature TeS2 of the sensible heat engine was set to 0.5 ℃. Here, the modification width of 0.5 ℃ corresponds to the amount of change in the evaporation temperature required to change the temperature of the air by 1.0 ℃ under the rated operating conditions of the second indoor unit 50.

As shown in fig. 15, in the first indoor unit 30, the width Δ Te1 of change in the first target evaporation temperature TeS1 becomes large, and therefore, the width Δ W1 of change in the cooling capacity per step also becomes large. Therefore, the proportion of the change width Δ W1 in the cooling capacity becomes large for the latent heat engine. As a result, the responsiveness of the latent heat engine to the cooling capacity can be improved. On the other hand, the change width Δ Te2 of the second target evaporation temperature TeS2 becomes smaller for the second indoor unit 50, and therefore the proportion of the change width Δ W2 of the cooling capacity per step becomes smaller. As a result, the cooling capacity of the heat developing machine can be adjusted with high accuracy.

Effects of the embodiment

In the above embodiment, the control device 60 performs the control operation (step control) of adjusting the cooling capacities of the indoor units 30 and 50 of the air conditioners 20 and 40 as the latent heat engines and the cooling capacities of the indoor units 30 and 50 of the air conditioners 20 and 40 as the sensible heat engines, respectively, so that the current indoor temperature and humidity approach the target value of the indoor temperature and humidity. More specifically, the control device 60 determines the cooling capacity of each of the indoor units 30 and 50 of the air conditioners 20 and 40 based on the target point S, the current air state point C, and the previous air state point C.

In this way, the relationship between the target point S and the current state point C of the air and the change in the state point C of the air can be considered, and it is possible to determine which of the sensible heat engine and the latent heat engine has to change the cooling capacity in which manner, and it is possible to quickly bring the state point C of the air close to the target point S. Therefore, the potentially split operation can be realized which is excellent in energy saving performance and can maintain the indoor temperature and humidity within a desired range.

In the above embodiment, after the target evaporation temperatures TeS of the latent heat engine and the sensible heat engine are determined in step St24, the cooling capacities of the air conditioners 20 and 40 are changed at the same time. For example, if the cooling capacities of the two are changed at different timings, the temperature and humidity in the room fluctuate and may not reach the target value. In contrast, by controlling the cooling capacities of the latent heat machine and the sensible heat machine at the same timing, the performance of the indoor temperature and humidity reaching the target values is improved.

(other embodiments)

In the step control of the above embodiment, the cooling capacity of each of the air conditioners 20 and 40 is determined in consideration of the target point S, the current air state point C, and the previous air state point C. However, the cooling capacity of each air conditioner 20, 40 may be determined by considering only the target point S and the current state point C of air, without considering the state point C of the previous air.

In the step control of the above embodiment, the cooling capacity is changed by adjusting the evaporation temperature of each air conditioner 20, 40, but instead of this, the operating frequency of the compressors 23, 43, the number of rotations of the indoor fans 33, 53, and the like may be adjusted.

The control device 60 of the above embodiment includes the cloud server 90, the communication terminal 80, and the like, and realizes the temperature/humidity control mode via the internet 86. However, the control device 60 may control the air conditioners 20 and 40 only by a local controller without passing through the internet.

Further, the air conditioning system 10 of the above embodiment is configured by two air conditioners 20 and 40 targeting the same indoor space 11, but three or more air conditioners 20 and 40 may be provided. In this case, it is also registered in advance which air conditioner becomes the latent heat engine and which air conditioner becomes the heat engine in the latent heat display separation operation. Then, in the latent heat and display separation operation, the ratio of the latent heat engine and the display engine is determined based on the registered information.

In the air conditioning system 10 of the above embodiment, the air conditioner may have a so-called multi-unit type structure for a building, which includes three or more indoor units and in which an indoor expansion valve is provided in a refrigerant circuit in the indoor units.

Industrial applicability-

In summary, the present invention is useful for an air conditioning system.

-description of symbols-

10 air conditioning system

20 first air conditioner

21 first outdoor unit

30 first indoor unit

40 second air conditioner

41 second outdoor unit

50 second indoor unit

60 control device

Claims (6)

1. An air conditioning system comprising: a plurality of air conditioners (20, 40) and a control device (60), wherein the plurality of air conditioners (20, 40) respectively have indoor units (30, 50) and outdoor units (21, 41), the plurality of air conditioners (20, 40) respectively perform refrigeration cycles individually, and the plurality of air conditioners (20, 40) respectively target the same indoor space, and the control device (60) controls the plurality of air conditioners (20, 40), the air conditioning system being characterized in that:

the control device (60) is configured to: the plurality of air conditioners (20, 40) are operated simultaneously,

in the simultaneous operation, at least one air conditioner (20) is controlled as a latent heat machine so that the indoor unit (30) of the one air conditioner (20) cools the air to a dew point temperature or lower, and the other air conditioner (40) is controlled as a sensible heat machine so that the indoor unit (50) of the other air conditioner (40) cools the air to a temperature higher than the dew point temperature,

the control device (60) also performs a control operation in which the cooling capacity of the indoor unit (30) of the air conditioner (20) as a latent heat engine and the cooling capacity of the indoor unit (50) of the air conditioner (40) as a sensible heat engine are respectively adjusted by the control device (60) so that the current indoor temperature and humidity approach a target value,

the control device (60) adjusts the evaporation temperature of the air conditioner (20) as the latent heat engine according to the indoor temperature and the indoor humidity, the target indoor temperature, and the target indoor humidity while maintaining the state of the latent heat engine in the air conditioner (20) as the latent heat engine during the control operation.

2. The air conditioning system of claim 1, wherein:

in the control operation, the cooling capacities of the indoor units (30, 50) of the air conditioners (20, 40) are determined by the control device (60) based on at least the target value and the current indoor temperature and humidity.

3. The air conditioning system of claim 2, wherein:

in the control operation, the cooling capacity of the indoor units (30, 50) of the air conditioners (20, 40) is determined by the control device (60) based on the target value, the current indoor temperature and humidity, and the indoor temperature and humidity before a predetermined time from the current indoor temperature and humidity.

4. An air conditioning system according to any one of claims 1 to 3, wherein:

the control device (60) causes the plurality of air conditioners (20, 40) to perform the simultaneous operation when the indoor temperature and the indoor humidity fall within a predetermined temperature and humidity range including the target value, and the control device (60) causes all the air conditioners (20, 40) to perform a dehumidification operation when the indoor humidity exceeds a predetermined humidity above the temperature and humidity range, and in the dehumidification operation, the control device (60) controls all the air conditioners (20, 40) such that the indoor units (30) of all the air conditioners (20, 40) cool air to a dew point temperature or lower.

5. An air conditioning system according to any one of claims 1 to 3, wherein:

in the control operation, the control device (60) controls the cooling capacity of the indoor unit (30) of the air conditioner (20) as a latent heat engine and the cooling capacity of the indoor unit (50) of the air conditioner (40) as a sensible heat engine at the same time.

6. The air conditioning system of claim 4, wherein:

in the control operation, the control device (60) controls the cooling capacity of the indoor unit (30) of the air conditioner (20) as a latent heat engine and the cooling capacity of the indoor unit (50) of the air conditioner (40) as a sensible heat engine at the same time.

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