JP7801975B2 - Control system and control method - Google Patents

Description

This disclosure relates to a control system and control method used in a variable air volume unit that controls the volume of air at a predetermined temperature supplied from an air conditioner installed in a building.

Variable air volume (VAV) units are devices that control the amount of air supplied by air conditioners installed in buildings. VAV units operate based on commands from control devices such as programmable logic controllers (PLCs).

VAV units have the function of adjusting the indoor temperature by changing the volume of air sent into a room based on conditions such as the operating mode (cooling/heating mode), the indoor temperature of the target room, and the set temperature. For example, Japanese Patent Application Laid-Open No. 2012-63117 (Patent Document 1) discloses technology for controlling the volume of air using a VAV unit.

JP 2012-63117 A

In the past, when using a single air conditioner to adjust the indoor temperatures of multiple rooms, a command for either cooling or heating operation mode was sent simultaneously to multiple VAV units installed in correspondence with each of the multiple rooms.

However, if there are rooms in a building where the temperature is likely to rise, such as a kitchen or gym, the air conditioning may be running even in winter, and the temperature environment may be significantly different from other rooms, such as an office.

As such, when a building contains multiple rooms with widely differing temperature environments, controlling all rooms using a uniform operating mode may not be able to properly adjust the indoor temperature of each room. It is also possible to install dedicated packaged air conditioning units for rooms with widely differing temperature environments, but this would increase the cost of the equipment.

The present disclosure has been made to solve the above-mentioned problems, and its purpose is to provide a control system and control method that can optimally control indoor temperature using a VAV unit.

The control system disclosed herein is a system used in a VAV unit that controls the volume of air at a predetermined temperature supplied from an air conditioner installed in a building. The control system includes a processor and memory that stores programs executable by the processor. Air from the air conditioner is supplied to rooms in the building via a supply path. VAV units are installed on the supply path corresponding to the rooms. When the indoor temperature measured by a temperature sensor installed in the room is higher than the set temperature for the room, the processor determines the operating mode of the VAV unit to be the cooling operating mode. When the indoor temperature is lower than the set temperature, the processor determines the operating mode to be the heating operating mode. The processor determines the operating amount of the VAV unit to control the volume of air based on the predetermined temperature, the indoor temperature, and the operating mode. The processor transmits the determined operating amount to the VAV unit.

The control method disclosed herein is a method for controlling a control system used in a VAV unit that controls the volume of airflow at a predetermined temperature supplied from an air conditioner installed in a building. Airflow from the air conditioner is supplied to rooms in the building via a supply path. VAV units are installed on the supply path corresponding to the rooms. The control method includes the steps of: determining the operating mode of the VAV unit to a cooling operating mode when the indoor temperature measured by a temperature sensor installed in the room is higher than the set temperature of the room; determining the operating mode to a heating operating mode when the indoor temperature is lower than the set temperature; determining the operating amount of the VAV unit to control the volume of airflow based on the predetermined temperature, the indoor temperature, and the operating mode; and transmitting the determined operating amount to the VAV unit.

According to the present disclosure, indoor temperature can be controlled effectively using a VAV unit.

FIG. 2 is a diagram illustrating an example of the hardware configuration of a control system and facilities in a building. FIG. 1 is a diagram for explaining a processing method in a conventional control system. FIG. 2 is a diagram for explaining a processing method in the control system according to the present embodiment. FIG. 10 is a diagram showing an example of a display of an allowable temperature determination result. 10 is a flowchart of a main process. 10 is a flowchart of a mode determination process. 10 is a flowchart of an air volume setting process. 10 is a flowchart of an air volume setting process. 10 is a flowchart of an allowable temperature determination process.

The following describes the embodiments with reference to the drawings. In the following description, identical components are designated by the same reference numerals. Their names and functions are also the same. Therefore, detailed descriptions of them will not be repeated.

Figure 1 shows an example of the hardware configuration of the control system 10 and the equipment in building 1. In this embodiment, building 1 (a building) has multiple rooms 20. In this example, building 1 has rooms 20a-c (also referred to as rooms 1-3) as rooms 20. Rooms 20 are, for example, rooms that house offices or stores.

Building 1 is equipped with an air conditioner 400, a variable air volume unit (hereinafter also referred to as a "VAV (Variable Air Volume) unit") 21, a control system 10, and other components. The control system 10 is a system that controls the air conditioner 400 and the VAV unit 21.

The VAV unit 21 adjusts the air volume supplied from the air conditioner 400 in response to fluctuations in the heat load of the room 20 to be air-conditioned. The VAV unit 21 includes an actuator (not shown) and a damper for adjusting the air volume, and can adjust the air volume by opening and closing the damper blades with the actuator (according to the opening degree of the damper blades). When the damper blades are fully open, the air volume is maximum, and when the damper blades are fully closed, the air volume is zero. The VAV unit 21 is also provided with a VAV controller (not shown) that controls the VAV unit 21, and the control system 10 controls the VAV unit 21 via the VAV controller.

Air from the air conditioner 400 is supplied to each room 20 (rooms 1-3) located in building 1 via duct 8, which serves as a supply path. The air conditioner 400 is connected to duct 8. Duct 8 branches so that air can be supplied to each room, and is connected to each room 20 (rooms 1-3). This allows air from the air conditioner 400 to be sent to each room 20 (rooms 1-3).

Hereinafter, the temperature of the air supplied from the air conditioner 400 will be referred to as the "supply air temperature." In this embodiment, air adjusted to a constant supply air temperature by the air conditioner 400 is sent from the air conditioner 400 to each room 20 (rooms 1 to 3). In this embodiment, the supply air temperature supplied from the air conditioner 400 to rooms 1 to 3 is 22°C. Note that the supply air temperature may be determined to an appropriate temperature taking into account the set temperature of each room 20. For example, if the set temperature of all rooms 1 to 3 is 24°C, the air conditioner 400 may be configured to send air at a supply air temperature of 24°C.

A VAV unit 21 is installed in the duct 8 corresponding to each room 20 (rooms 1 to 3). The portions of the duct 8 that branch off toward each room 20 are called ducts 8a to 8c. Duct 8a, which branches off from duct 8, is connected to room 1 (room 20a), duct 8b, which branches off from duct 8, is connected to room 2 (room 20b), and duct 8c, which branches off from duct 8, is connected to room 3 (room 20c).

VAV unit 21a is installed in duct 8a corresponding to room 1, VAV unit 21b is installed in duct 8b corresponding to room 2, and VAV unit 21c is installed in duct 8c corresponding to room 3.

The control system 10 sends commands (air volume commands) to each VAV unit 21 to adjust the air volume. Each VAV unit 21 then controls the air volume sent to room 20 based on these commands. VAV unit 21a controls the air volume sent to room 1, VAV unit 21b controls the air volume sent to room 2, and VAV unit 21c controls the air volume sent to room 3.

In addition, a sensor 23 is installed in each of rooms 1 to 3 as a temperature sensor. The sensor 23 measures the indoor temperature of each room 20 (rooms 1 to 3). The control device 100 can acquire the indoor temperature measured by the sensor 23 in each room 20.

The control device 100 controls the VAV unit 21 to adjust the volume of air sent to each room 20 so that the indoor temperature in each room 20 becomes a preset temperature.

In the example of Figure 1, the supply air temperature from the air conditioner 400 is 22°C. The set temperature of Room 1 is 20°C, and the current indoor temperature is 30°C. The set temperature of Room 2 is 28°C, and the current indoor temperature is 26°C. The set temperature of Room 3 is 15°C, and the current indoor temperature is 19°C.

The control system 10 includes a control device 100, a server 200, and a terminal 300. The control device 100 is, for example, a programmable logic controller (PLC) and is capable of communicating with the air conditioner 400 and each VAV unit 21.

The server 200 can communicate with the control device 100 and the terminal 300. The server 200 can monitor and control the air conditioner 400 and each VAV unit 21 via the control device 100. Various information acquired by the server 200 is sent to the terminal 300.

The terminal 300 is used by the manager of building 1. The display unit 320 of the terminal 300 displays various information acquired by the server 200. Furthermore, the air conditioner 400 and each VAV unit 21 can be controlled (for example, by changing the set temperature) by operating the input unit 310 of the terminal 300.

The control device 100 includes a processor 101, memory 102, a communication interface (not shown) for connecting to the server 200, and an input/output card for connecting to the air conditioner 400. These are connected to each other via a bus so that they can communicate with each other. The processor 101 is a CPU (Central Processing Unit). The memory 102 is composed of a ROM (Read Only Memory), a RAM (Random Access Memory), and a storage unit.

The CPU loads programs stored in ROM into RAM and executes them to realize the various functions of the control device 100. The ROM stores programs that describe the processing procedures of the control device 100. The RAM serves as a working area when the CPU executes programs, and temporarily stores programs and data used when executing programs. The storage unit is a non-volatile storage device. The storage unit may be, for example, an HDD (Hard Disk Drive) or SSD (Solid State Drive).

The control device 100 inputs and outputs signals from the air conditioner 400 via input/output cards. The input/output cards consist of a digital input card for inputting digital signals, an analog input card for inputting analog signals, a digital output card for outputting digital signals, and an analog output card for outputting analog signals. Each input/output card has a terminal block with multiple terminals. The air conditioner 400 inputs digital signals to the control device 100 via terminals on the terminal block of the digital input card. The air conditioner 400 inputs analog signals to the control device 100 via terminals on the terminal block of the analog input card. The control device 100 outputs digital signals to the air conditioner 400 via terminals on the terminal block of the digital output card. The control device 100 outputs analog signals to the air conditioner 400 via terminals on the terminal block of the analog output card. The signals output from the air conditioner 400 can ultimately be acquired by the server 200 via the control device 100. The signals output from the server 200 are transmitted to the air conditioner 400 via the control device 100.

The server 200 includes a processor (CPU), memory, and a communication interface (not shown). These are connected to each other via a bus so that they can communicate with each other. The memory may also include ROM, RAM, and a storage unit.

The CPU loads programs stored in ROM into RAM and executes them to realize the various functions of the server 200. The ROM stores programs that describe the processing procedures of the server 200. The RAM serves as a working area when the CPU executes programs, and temporarily stores programs and data used when executing programs. The storage unit is a non-volatile storage device, and may be an HDD, SSD, etc.

The terminal 300 includes a CPU, ROM, RAM, a storage unit, a communication interface, an input unit 310, and a display unit 320 (not shown). These are connected to each other via a bus so that they can communicate with each other.

The CPU loads programs stored in ROM into RAM and executes them to realize the various functions of the terminal 300. The ROM stores programs that describe the processing procedures of the terminal 300. The RAM serves as a working area when the CPU executes programs, and temporarily stores programs and data used when executing programs. The storage unit is a non-volatile storage device, and may be an HDD, SSD, etc.

The input unit 310 accepts input from the user. The input unit 310 is, for example, a touch panel, but may also be a keyboard or mouse. The display unit 320 displays various types of information. The display unit 320 is, for example, a liquid crystal display or display.

Figure 2 is a diagram illustrating the processing method used in a conventional control system. The conditions in each room are the same as in the example in Figure 1. In the conventional processing method, the control device 100 first calculates the average indoor temperature of rooms 1 to 3. The average indoor temperature is 25°C (= (30°C + 26°C + 19°C) / 3). Hereafter, processing is performed assuming that the average indoor temperature = the indoor temperature of each room. The supply air temperature is set to 22°C.

When the supply air temperature is lower than the average indoor temperature, the control device 100 assumes that the air supplied from the air conditioner 400 can lower the temperature of each room 20 (rooms 1 to 3) and determines the operation mode to be "cooling operation mode." When the supply air temperature is higher than the average indoor temperature, the control device 100 assumes that the air supplied from the air conditioner 400 can raise the temperature of each room 20 and determines the operation mode to be "heating operation mode."

In this example, it is assumed that the indoor temperature of each room 20 is 25°C, and the supply air temperature of the air sent from the air conditioner 400 is 22°C. Therefore, it is determined that the indoor temperature will decrease (cooling operation will be performed) by sending air at a supply air temperature (22°C) that is lower than the indoor temperature (25°C). On the other hand, if air at a supply air temperature that is higher than the indoor temperature is sent, it is determined that the indoor temperature will increase (heating operation will be performed).

In Room 1, the set temperature is 20°C, while the average indoor temperature is 25°C, so it is determined that the indoor temperature can be lowered by sending air with a supply temperature of 22°C. Therefore, the control device 100 controls the VAV unit 21a to send air to Room 1 (increase the airflow).

In Room 2, the set temperature is 28°C, while the average indoor temperature is 25°C. In this case, it is necessary to raise the temperature from 25°C to 28°C. However, the control device 100 determines that performing cooling operation to blow air with a supply air temperature of 22°C would further lower the average indoor temperature of 25°C, and controls the VAV unit 21b to stop blowing air to Room 2 (or reduce the amount of air blown).

In Room 3, the set temperature is 15°C, while the average indoor temperature is 25°C. In this case, the control device 100 determines that the indoor temperature can be lowered by performing cooling operation, which sends out air with a supply air temperature of 22°C, which is lower than the average indoor temperature of 25°C, and controls the VAV unit 21c to send air to Room 3 (increase the airflow). However, the indoor temperature in Room 3 is actually 19°C. If air with a supply air temperature of 22°C were sent out, the indoor temperature would actually rise.

In conventional processing methods, the system was configured as described above under the assumption that the indoor temperature in each room in the same building would rise in the same way in the summer, and that the same set temperature would be set. For example, in an office building, suppose the indoor temperature in each room is 20°C and the set temperature in each room is 24°C. In this case, the average indoor temperature is 20°C. By running the heating operation to blow air with a supply temperature of 24°C, the temperature in all rooms can be raised to the set temperature.

However, in special environments where the indoor temperature is likely to rise, such as fitness gyms and kitchens, there may be cases where the temperature needs to be lowered (air conditioning is used) even in winter. Alternatively, in special environments where a low indoor temperature needs to be maintained, it is conceivable that the indoor temperature will need to be lowered even further in winter.

In buildings with special circumstances like these, conventional methods use the average indoor temperature for control, which can sometimes result in inadequate temperature control. When there are rooms with special temperature environments like these, it may be possible to install separate, dedicated air conditioning units. However, there are cases where it is not possible to install multiple air conditioning units within a building due to equipment costs, or where tenant changes could result in a tenant unexpectedly moving in with a special temperature environment.

In this embodiment, taking these special circumstances into consideration, the control device 100 is configured as described below. Figure 3 is a diagram for explaining the processing method used by the control system 10 in this embodiment. In this embodiment, information on the indoor temperature of each room is used.

In this embodiment, the supply air temperature is 22°C. The supply air temperature is a temperature that is set in advance to adjust the indoor temperature of each room in building 1. For example, the manager of building 1 may set the supply air temperature, or the average of the set temperatures of all rooms in building 1 may be set as the supply air temperature.

In Room 1, the indoor temperature is 30°C and the set temperature is 20°C. The control device 100 determines that "cooling operation" is necessary to lower the temperature to a set temperature lower than the indoor temperature. Room 1 can be supplied with air at a supply temperature of 22°C. In this case, the control device 100 controls the VAV unit 21a to send air at a lower temperature of 22°C into the 30°C room, bringing the temperature closer to the set temperature of 20°C.

In Room 2, the indoor temperature is 26°C and the set temperature is 28°C. The control device 100 determines that "heating operation" is necessary to raise the temperature to a set temperature higher than the indoor temperature. Room 2 can be supplied with air at a supply temperature of 22°C. In this case, the control device 100 controls the VAV unit 21b to reduce the amount of air sent to Room 2 (or stop sending air), because sending air at a lower temperature of 22°C into a room with a temperature of 26°C would actually lower the room temperature.

In Room 3, the indoor temperature is 19°C and the set temperature is 15°C. The control device 100 determines that "cooling operation" is necessary to lower the temperature to a set temperature lower than the indoor temperature. Room 3 can be supplied with air at a supply temperature of 22°C. In this case, the control device 100 controls the VAV unit 21c to reduce the amount of air sent to Room 3 (or stop sending air), because sending air at a higher temperature of 22°C into a room with a temperature of 19°C would actually raise the room temperature. The control device 100 will then control the VAV unit 21c to reduce the amount of air sent to Room 3 (or stop sending air). Details of this process will be explained in detail using the flowcharts in Figures 5 to 8.

In addition, in this embodiment, an allowable temperature range can be set for each room 20. The allowable temperature range indicates the temperature range that the occupant of each room 20 can tolerate as an indoor temperature. If the current indoor temperature or the indoor temperature resulting from cooling/heating operation is within the set allowable temperature range, the occupant of the room will accept it.

In this example, the allowable temperature range for Room 1 is set to 17°C to 23°C. In this case, by operating in cooling mode and supplying air with a supply temperature of 22°C, it is possible to lower the indoor temperature to 22°C. As a result, the indoor temperature of Room 1 can be controlled within the allowable temperature range (17°C to 23°C), meeting the needs of the occupants of Room 1.

The allowable temperature range for Room 2 is set to 26°C to 30°C. Even if air with a supply temperature of 22°C is supplied to Room 2, it will not be possible to raise the temperature to the set point. However, because the current indoor temperature of Room 2 (26°C) is within the allowable temperature range (26°C to 30°C), the needs of the users of Room 2 will be met even if the indoor temperature is not controlled.

The allowable temperature range for Room 3 is set to 13°C to 17°C. Even if air with a supply temperature of 22°C is supplied to Room 3, it will not be possible to lower the temperature to the set temperature. Furthermore, because the current indoor temperature of Room 3 (19°C) is outside the allowable temperature range (13°C to 17°C), the needs of the users of Room 3 cannot be met, whether the indoor temperature is controlled or not.

Figure 4 shows an example of the display of the allowable temperature judgment result. The display unit 320 of the terminal 300 can display various information that the server 200 has acquired from the control device 100. Figure 4 displays the information exemplified in Figure 3.

As shown in Figure 4, the supply air temperature from the air conditioner 400 is shown to be 22°C. Furthermore, for Room 1, the set temperature is shown to be "20°C," the indoor temperature is shown to be "30°C," and the allowable temperature range is shown to be "17°C to 23°C." Since the indoor temperature of Room 1 can be controlled within the allowable temperature range (17°C to 23°C) by performing cooling operation, "Within allowable temperature range: OK" is displayed.

For Room 2, the set temperature is "28°C," the indoor temperature is "26°C," and the allowable temperature range is "26°C to 30°C." Since the indoor temperature of Room 2 (26°C) is within the allowable temperature range (26°C to 30°C), "Within allowable temperature range: OK" is displayed.

For Room 3, the set temperature is "15°C," the indoor temperature is "19°C," and the allowable temperature range is "13°C to 17°C." Since the indoor temperature of Room 3 (15°C) cannot be kept within the allowable temperature range (13°C to 17°C) whether the indoor temperature is controlled or not, "Within allowable temperature range: NG" is displayed.

The processing executed by the control device 100 will be explained below using a flowchart. Figure 5 is a flowchart of the main processing. The control device 100 executes the main processing. The main processing can be started periodically (for example, every second, every 10 seconds, or every minute). Hereinafter, "step" will also be referred to simply as "S."

When the main processing starts, the control device 100 acquires various information in S101. The acquired information includes the supply air temperature, the set temperature of each room 20, the indoor temperature, the allowable temperature range, the operating status of each VAV unit 21, etc.

In S102, the control device 100 sets i = 0. In S103, the control device 100 adds 1 to i. In S104, the control device 100 sets the i-th VAV unit 21 and room. As a result, first, i = 1 is set in S103, and then the first VAV unit (VAV unit 21a) and room 1 (room 20a) are set in S104.

In S105, the control device 100 executes a mode determination process (see FIG. 6, described below). In S106, the control device 100 executes an airflow setting process (see FIGS. 7 and 8, described below). In S107, the control device 100 executes an allowable temperature determination process (see FIG. 9, described below). This first determines the operating mode and airflow setting of the VAV unit 21a corresponding to room 1, and determines whether the temperature is within the allowable temperature range.

In S108, the control device 100 determines whether i = maximum number of rooms N. The maximum number of rooms N is the number of rooms installed in building 1, and in this embodiment, the maximum number of rooms N = 3.

If the control device 100 determines that i = the maximum number of rooms N (YES in S108), it proceeds to S109. On the other hand, if the control device 100 determines that i does not = the maximum number of rooms N (NO in S108), it returns to S103.

In the above example, i = 1, so processing returns to S103. Next, i = 2 is set in S103, and the second VAV unit (VAV unit 21b) and room 2 (room 20b) are set in S104. As a result, in S105 to S107, the operating mode and airflow setting for VAV unit 21b corresponding to room 2 are determined, and it is determined whether the temperature is within the allowable temperature range.

Furthermore, since i = 2, processing returns to S103 after a NO determination in S108. Then, i = 3 is set in S103, and the third VAV unit (VAV unit 21c) and room 3 (room 20c) are set in S104. As a result, in S105 to S107, the operating mode and airflow setting for VAV unit 21c corresponding to room 3 are determined, and it is determined whether the temperature is within the allowable temperature range. In this case, since i = 3 = the maximum number of rooms N, processing proceeds to S109 after a YES determination in S108.

In S109, the control device 100 transmits the determined operating volume to each VAV unit 21 (VAV units 21a-c) as an airflow command. As a result, VAV units 21a-c operate based on the command from the control device 100.

In S110, the control device 100 transmits display information to the terminal 300 and ends the main processing. The display information includes the supply air temperature, the set temperature for each room 20, the indoor temperature, the allowable temperature range, and information indicating whether the temperature is within the allowable temperature range. As a result, various information is displayed on the display unit 320 of the terminal 300, as shown in Figure 4.

Figure 6 is a flowchart of the mode determination process. When the indoor temperature measured by the sensor 23 installed in the room 20 is higher than the set temperature of the room 20, the control device 100 determines the operating mode of the corresponding VAV unit 21 to be the cooling operating mode. When the indoor temperature measured by the sensor 23 installed in the room 20 is lower than the set temperature, the control device 100 determines the operating mode to be the heating operating mode.

Specifically, when the mode determination process begins, the control device 100 determines in S201 whether the indoor temperature is greater than the set temperature in the target room 20. If the control device 100 determines that the indoor temperature is greater than the set temperature (YES in S201), it sets the operating mode of the target VAV unit 21 to the cooling operating mode (cooling operation setting) in S202, and ends the mode determination process.

If the control device 100 does not determine that the indoor temperature is greater than the set temperature (NO in S201), it determines in S203 whether the indoor temperature is less than the set temperature in the target room 20. If the control device 100 determines that the indoor temperature is less than the set temperature (YES in S203), it sets the operation mode of the target VAV unit 21 to the heating operation mode (heating operation setting) in S204 and ends the mode determination process. If the control device 100 does not determine that the indoor temperature is less than the set temperature (NO in S203), it ends the mode determination process.

In the example of Figure 3, the operation mode of VAV unit 21a corresponding to room 1 is set to cooling operation mode, the operation mode of VAV unit 21b corresponding to room 2 is set to heating operation mode, and the operation mode of VAV unit 21c corresponding to room 3 is set to cooling operation mode.

Figures 7 and 8 are flowcharts of the air volume setting process. The control device 100 determines the operating amount of the VAV unit 21 for controlling the air volume based on the supply air temperature, indoor temperature, and operating mode of the target room 20.

In this embodiment, the operating amount of the VAV unit 21 is the opening degree of the damper blades of the VAV unit 21. There is a fixed relationship between the opening degree of the damper blades of the VAV unit 21 and the air volume sent to the corresponding room 20. When the damper blades are fully closed, the air volume is 0, and the air volume increases as the opening degree of the damper blades increases, reaching a maximum when the damper blades are fully open. For example, when the operating amount = A1, the air volume = B1, when the operating amount = A2, the air volume = B2, and when the operating amount = A3, the air volume = B3. When A1 < A2 < A3, the relationship B1 < B2 < B3 holds. In this embodiment, the operation is as follows:

When the VAV unit 21 is operating with the operating amount = A2, if the operating mode is determined to be the cooling operating mode and the supply air temperature is lower than the room temperature, the control device 100 determines the operating amount = A3 (> A2). In other words, if the operating mode is determined to be the cooling operating mode and the supply air temperature is lower than the room temperature, the VAV unit 21 increases the opening of the damper blades to increase the airflow.

When the VAV unit 21 is operating with the operating amount = A2, if the operating mode is determined to be the cooling operating mode and the supply air temperature is higher than the room temperature, the control device 100 determines the operating amount = A1 (< A2). In other words, if the operating mode is determined to be the cooling operating mode and the supply air temperature is higher than the room temperature, the VAV unit 21 reduces the opening of the damper blades so that the air volume decreases.

When the VAV unit 21 is operating with the operating amount = A2, if the operating mode is determined to be the heating operating mode and the supply air temperature is higher than the room temperature, the control device 100 determines the operating amount = A3 (> A2). In other words, if the heating operating mode is determined and the supply air temperature is higher than the room temperature, the VAV unit 21 increases the opening of the damper blades to increase the airflow.

When the VAV unit 21 is operating with the operating amount = A2, if the operating mode is determined to be the heating operating mode and the supply air temperature is lower than the room temperature, the control device 100 determines the operating amount = A1 (< A2). In other words, if the operating mode is determined to be the heating operating mode and the supply air temperature is lower than the room temperature, the VAV unit 21 reduces the opening of the damper blades so that the air volume decreases.

As shown in FIG. 7, when the air volume setting process starts, the control device 100 determines in S301 whether the operation mode is cooling. If the control device 100 determines that the operation mode is cooling (YES in S301), the process proceeds to S302. If the control device 100 does not determine that the operation mode is cooling (NO in S301), the process proceeds to "A" (S401 in FIG. 8).

In S302, the control device 100 determines whether the supply air temperature is less than the room temperature. If the control device 100 determines that the supply air temperature is less than the room temperature (YES in S302), it sets an increase in the air volume in S303 and terminates the air volume setting process. Specifically, as described above, the control device 100 sets the operation amount so that the opening degree (operation amount) of the damper blades of the VAV unit 21 increases (air volume increases).

If the control device 100 does not determine that the supply air temperature is less than the room temperature (NO in S302), it determines in S304 whether the supply air temperature is greater than the room temperature. If the control device 100 determines that the supply air temperature is greater than the room temperature (YES in S304), it sets a decrease in the air volume in S305 and terminates the air volume setting process. Specifically, as described above, the control device 100 sets the operating amount so that the opening degree (operating amount) of the damper blades of the VAV unit 21 is reduced (air volume is reduced). If the control device 100 does not determine that the room supply air temperature is greater than the room temperature (NO in S304), it terminates the air volume setting process.

As shown in FIG. 8, the control device 100 determines in S401 whether the operation mode is heating. If the control device 100 determines that the operation mode is heating (YES in S401), the process proceeds to S402. If the control device 100 does not determine that the operation mode is heating (NO in S401), the process proceeds to "B" (FIG. 7), and the air volume setting process ends.

In S402, the control device 100 determines whether the supply air temperature is greater than the room temperature. If the control device 100 determines that the supply air temperature is greater than the room temperature (YES in S402), it sets an increase in the air volume in S403 and terminates the air volume setting process. Specifically, as described above, the control device 100 sets the operation amount so that the opening degree (operation amount) of the damper blades of the VAV unit 21 increases (air volume increases).

If the control device 100 does not determine that the supply air temperature is greater than the room temperature (NO in S402), it determines in S404 whether the supply air temperature is less than the room temperature. If the control device 100 determines that the supply air temperature is less than the room temperature (YES in S404), it sets a decrease in the air volume in S405 and ends the air volume setting process. Specifically, as described above, the control device 100 sets the operating amount so that the opening degree (operating amount) of the damper blades of the VAV unit 21 is reduced (air volume is reduced). If the control device 100 does not determine that the room supply air temperature is less than the room temperature (NO in S404), it proceeds to "B" (Figure 7) and ends the air volume setting process.

In the example of Figure 3, the VAV unit 21a corresponding to room 1 is set to increase the airflow in cooling operation mode (S303), the VAV unit 21b corresponding to room 2 is set to decrease the airflow in heating operation mode (S405), and the VAV unit 21c corresponding to room 3 is set to decrease the airflow in cooling operation mode (S305).

For example, A1 = damper blade fully closed state, air volume B1 = 0, A3 = damper blade fully open state, air volume B3 = maximum air volume, and A1 < A2 (for example, the opening of the damper blades in the initial state (when the power is turned on)) < A3. In this case, in S303 and S403, if the opening of the damper blades is in the initial state, the air volume is maximized by changing it to the fully open state, and if the opening of the damper blades is in the fully open state, the maximum air volume state is maintained. In S305 and S405, if the opening of the damper blades is in the initial state, the airflow is stopped by changing it to the fully closed state, and if the opening of the damper blades is in the fully closed state, the airflow stopped state is maintained.

In addition to the above, a table showing the relationship between the difference between the indoor temperature and the set temperature and the opening degree (amount of operation) of the damper blades of the VAV unit 21 when the operating mode is cooling can be prepared in advance, and the amount of operation can be determined based on this table. In this case, if the indoor temperature is greater than the set temperature and the difference is greater (the higher the indoor temperature), the damper blade opening can be controlled to be greater. Also, if the indoor temperature is less than the set temperature, the damper blade opening can be set to 0 or a predetermined opening degree.

Similarly, a table showing the relationship between the difference between the room temperature and the set temperature and the opening degree (amount of operation) of the damper blades of the VAV unit 21 when the operating mode is heating may be prepared in advance, and the amount of operation may be determined based on this table. In this case, if the room temperature is less than the set temperature and the difference is greater (the lower the room temperature), the opening degree of the damper blades may be controlled to be greater. Also, if the room temperature is greater than the set temperature, the opening degree of the damper blades may be set to 0 or a predetermined opening degree.

As explained above, in this embodiment, when the indoor temperature of room 20 is higher than the set temperature, the cooling operation mode is selected, and when the indoor temperature is lower than the set temperature, the heating operation mode is selected. The amount of operation of the VAV unit 21 is determined based on the supply air temperature, indoor temperature, and operation mode. In this way, because the operation mode for each room is determined based on the relationship between the indoor temperature of each room and the set temperature, when operating multiple VAV units 21 corresponding to multiple rooms, it is possible to accommodate special temperature environments such as operating in cooling operation mode in winter and operating in heating operation mode in summer, and the VAV unit 21 can be controlled to suit the temperature environment of each room. This allows for optimal indoor temperature control using the VAV unit 21.

Furthermore, it is generally not conceivable that the supply air temperature would be less than the room temperature even when the heating operation mode has been selected (the room temperature would drop due to the supply air), or that the supply air temperature would be greater than the room temperature even when the cooling operation mode has been selected (the room temperature would rise due to the supply air). However, in this embodiment, even under such special circumstances, the room temperature can be suitably controlled using the VAV unit 21, as described using Figures 3 to 8.

Figure 9 is a flowchart of the allowable temperature determination process. The allowable temperature range, which indicates the temperature range that the occupants of each room 20 (rooms 1 to 3) can tolerate as an indoor temperature, can be input and set from the terminal 300. In the example of Figure 4, the input unit 310 of the terminal 300 indicates that the occupant of room 1 can tolerate an indoor temperature of 17 to 23°C (allowable temperature range), and this is displayed. Similarly, the allowable temperature range for the occupant of room 2 is set to 26 to 36°C, and the allowable temperature range for the occupant of room 3 is set to 13 to 17°C.

When the allowable temperature determination process is started, if the control device 100 determines that the current indoor temperature or the indoor temperature after temperature control is within the allowable temperature range (YES in S501), it sets this to be within the allowable temperature range (S502) and terminates the allowable temperature determination process.

In the example shown in Figure 3, the indoor temperature in Room 1 can be lowered from 30°C to 22°C (supply air temperature) through cooling operation. As a result, the indoor temperature can be controlled within the allowable temperature range (17-22°C), and so it is set to be within the allowable temperature range. Then, in Figure 4, "Within allowable temperature range: OK" is displayed.

Furthermore, in Room 2, the indoor temperature cannot be controlled by heating operation. However, since the indoor temperature (26°C) is within the allowable temperature range (26-30°C), it is set to be within the allowable temperature range. Then, in Figure 4, "Within allowable temperature range: OK" is displayed.

If the control device 100 does not determine that the current indoor temperature or the indoor temperature after temperature control is within the allowable temperature range (NO in S501), it sets a value indicating that the temperature is outside the allowable temperature range (S503) and terminates the allowable temperature determination process.

In the example shown in Figure 3, the indoor temperature in Room 3 cannot be controlled by cooling operation. Since the indoor temperature (19°C) is outside the allowable temperature range (13-17°C), it is set to be within the allowable temperature range. In Figure 4, "Within allowable temperature range: NG" is displayed.

As explained above, the control device 100 determines whether the indoor temperature can be controlled within the allowable temperature range. Here, "the indoor temperature can be controlled within the allowable temperature range" includes cases where the indoor temperature is controlled within the allowable temperature range as a result of the indoor temperature being controlled by the VAV unit 21, and cases where the indoor temperature is not controlled by the VAV unit 21 but the current indoor temperature is already within the allowable temperature range. If the indoor temperature cannot be controlled within the allowable temperature range, the display unit 320 will display that fact.

This allows the user of a room to know whether the temperature is tolerable (uncomfortable) in special temperature environments, such as when blowing air at the supply temperature in heating mode causes the temperature to drop and the temperature cannot be adjusted to the set temperature, or when blowing air at the supply temperature in cooling mode causes the temperature to rise and the temperature cannot be adjusted to the set temperature. This configuration is particularly useful when a tenant who uses a room in a special temperature environment moves into Building 1. In this case, the manager of Building 1 can detect the tenant's dissatisfaction in advance and take measures such as installing new heating and cooling equipment in the room.

The above-described embodiment may also be configured as follows:

A control system used in a VAV unit that controls the volume of air at a predetermined temperature supplied from an air conditioner installed in a building,
a processor;
a memory that stores a program executable by the processor;
The air from the air conditioner is supplied to each of a plurality of rooms arranged in the building via paths branching from a supply path,
a VAV unit corresponding to each of the plurality of rooms is installed in a path branched from the supply path,
The processor:
When an indoor temperature measured by a temperature sensor installed in each of the plurality of rooms is higher than a set temperature of the room, the operation mode of the VAV unit corresponding to the room is determined to be a cooling operation mode;
When an indoor temperature measured by a temperature sensor installed in each of the plurality of rooms is lower than a set temperature of the room, the operation mode of the VAV unit corresponding to the room is determined to be a heating operation mode;
determining an operation amount of a VAV unit corresponding to each room for controlling the airflow volume based on the predetermined temperature, the indoor temperature of each of the plurality of rooms, and an operation mode of a VAV unit corresponding to each room;
A control system that transmits an operation amount of a VAV unit corresponding to each of the plurality of rooms to the VAV unit.

[Note]
The above-described embodiment is a specific example of the following additional notes.

(Appendix 1)
A control system used in a VAV unit that controls the volume of air at a predetermined temperature supplied from an air conditioner installed in a building,
a processor;
a memory that stores a program executable by the processor;
The air from the air conditioner is supplied to a room arranged in the building via a supply path,
the VAV unit is installed on the supply path corresponding to the room,
The processor:
determining an operating mode of the VAV unit to be a cooling operating mode when the indoor temperature measured by a temperature sensor installed in the room is higher than a set temperature of the room;
When the indoor temperature is lower than the set temperature, the operation mode is determined to be a heating operation mode;
determining an operation amount of the VAV unit for controlling the air volume based on the predetermined temperature, the indoor temperature, and the operation mode;
A control system that transmits the determined operating amount to the VAV unit.

(Appendix 2)
the operating amounts include a first operating amount of the VAV unit where the air volume is controlled to a first air volume, a second operating amount of the VAV unit where the air volume is controlled to a second air volume that is larger than the first air volume, and a third operating amount of the VAV unit where the air volume is controlled to a third air volume that is larger than the second air volume,
The processor:
When the VAV unit is operating at the second operating amount, if the operating mode is determined to be the cooling operating mode and the predetermined temperature is lower than the room temperature, the operating amount is determined to be the third operating amount;
When the VAV unit is operating at the second operating amount, if the operating mode is determined to be the cooling operating mode and the predetermined temperature is higher than the indoor temperature, the operating amount is determined to be the first operating amount;
When the VAV unit is operating at the second operating amount, if the operating mode is determined to be the heating operating mode and the predetermined temperature is higher than the room temperature, the operating amount is determined to be the third operating amount;
2. The control system of claim 1, wherein when the VAV unit is operating at the second operating amount, if the operating mode is determined to be the heating operating mode and the predetermined temperature is lower than the indoor temperature, the operating amount is determined to be the first operating amount.

(Appendix 3)
an input unit for inputting an allowable temperature range indicating a temperature range that a user of the room can tolerate as the indoor temperature,
3. The control system of claim 1, wherein the processor determines whether the indoor temperature can be controlled to be within the acceptable temperature range.

(Appendix 4)
The control system according to any one of Supplementary Note 1 to Supplementary Note 3, further comprising a display unit that displays a message to the effect that the indoor temperature cannot be controlled within the allowable temperature range when the indoor temperature cannot be controlled within the allowable temperature range.

(Appendix 5)
A control method for controlling a control system used in a VAV unit that controls the volume of air at a predetermined temperature supplied from an air conditioner installed in a building, comprising:
The air from the air conditioner is supplied to a room arranged in the building via a supply path,
the VAV unit is installed on the supply path corresponding to the room,
The control method includes:
determining an operation mode of the VAV unit to be a cooling operation mode when an indoor temperature measured by a temperature sensor installed in the room is higher than a set temperature of the room;
determining the operation mode to be a heating operation mode when the indoor temperature is lower than the set temperature;
determining an operation amount of the VAV unit for controlling the airflow rate based on the predetermined temperature, the indoor temperature, and the operation mode;
and transmitting the determined amount of operation to the VAV unit.

The embodiments disclosed herein are illustrative and are not limited to the above. The scope of the present invention is defined by the claims, and it is intended to include all modifications that are equivalent to and within the scope of the claims.

1 Building, 8 Duct, 10 Control system, 20, 20a-20c Rooms, 21 VAV unit, 23 Sensor, 100 Control device, 101 Processor, 102 Memory, 200 Server, 300 Terminal, 310 Input unit, 320 Display unit, 400 Air conditioner.

Claims (4)

A control system used in a variable air volume unit that controls the volume of air at a predetermined temperature supplied from an air conditioner installed in a building,
a processor;
a memory that stores a program executable by the processor;
The air from the air conditioner is supplied to a room arranged in the building via a supply path,
the variable air volume unit is installed in the supply path corresponding to the room,
The processor:
determining an operating mode of the variable air volume unit to a cooling operating mode when the room temperature measured by a temperature sensor installed in the room is higher than a set temperature of the room;
When the indoor temperature is lower than the set temperature, the operation mode is determined to be a heating operation mode;
the operating amount of the variable air volume unit for controlling the air volume includes a first operating amount of the variable air volume unit for controlling the air volume to a first air volume, a second operating amount of the variable air volume unit for controlling the air volume to a second air volume greater than the first air volume, and a third operating amount of the variable air volume unit for controlling the air volume to a third air volume greater than the second air volume;
The processor:
When the variable air volume unit is operating at the second operating amount, if the operating mode is determined to be the cooling operating mode and the predetermined temperature is lower than the room temperature, the operating amount is determined to be the third operating amount;
When the variable air volume unit is operating at the second operating amount, if the operating mode is determined to be the cooling operating mode and the predetermined temperature is higher than the indoor temperature, the operating amount is determined to be the first operating amount;
When the variable air volume unit is operating at the second operating amount, if the operating mode is determined to be the heating operating mode and the predetermined temperature is higher than the room temperature, the operating amount is determined to be the third operating amount;
When the variable air volume unit is operating at the second operating amount, if the operating mode is determined to be the heating operating mode and the predetermined temperature is lower than the room temperature, the operating amount is determined to be the first operating amount;
A control system that transmits the determined operating amount to the variable air volume unit. an input unit for inputting an allowable temperature range indicating a temperature range that a user of the room can tolerate as the indoor temperature,
The control system of claim 1 , wherein the processor determines whether the indoor temperature can be controlled within the acceptable temperature range. The control system according to claim 2 , further comprising a display unit that displays a message to the effect that the indoor temperature cannot be controlled within the allowable temperature range when the indoor temperature cannot be controlled within the allowable temperature range. A control method for controlling a control system used in a variable air volume unit that controls the volume of air at a predetermined temperature supplied from an air conditioner installed in a building, comprising:
The air from the air conditioner is supplied to a room arranged in the building via a supply path,
the variable air volume unit is installed in the supply path corresponding to the room,
The control method includes:
determining an operating mode of the variable air volume unit to a cooling operating mode when an indoor temperature measured by a temperature sensor installed in the room is higher than a set temperature of the room;
determining the operation mode to be a heating operation mode when the indoor temperature is lower than the set temperature;
the operating amount of the variable air volume unit for controlling the air volume includes a first operating amount of the variable air volume unit for controlling the air volume to a first air volume, a second operating amount of the variable air volume unit for controlling the air volume to a second air volume greater than the first air volume, and a third operating amount of the variable air volume unit for controlling the air volume to a third air volume greater than the second air volume;
The control method includes:
determining the operating amount to the third operating amount when the operating mode is determined to be the cooling operating mode and the predetermined temperature is lower than the room temperature while the variable air volume unit is operating at the second operating amount;
determining the operating amount to the first operating amount when the operating mode is determined to be the cooling operating mode and the predetermined temperature is higher than the room temperature while the variable air volume unit is operating at the second operating amount;
determining the operation amount to the third operation amount when the operation mode is determined to be the heating operation mode and the predetermined temperature is higher than the room temperature while the variable air volume unit is operating at the second operation amount;
When the variable air volume unit is operating at the second operating amount, if the operating mode is determined to be the heating operating mode and the predetermined temperature is lower than the room temperature, determining the operating amount to be the first operating amount;
and transmitting the determined operation amount to the variable air volume unit.