JP7756293B2 - Ventilation Control System - Google Patents

Description

This disclosure relates to ventilation control technology, and in particular to a ventilation control system that controls ventilation in a facility.

In an air conditioning system for a highly insulated, airtight house with multiple rooms, the air conditioning in at least one independently installed air-conditioned room is controlled, and the conditioned air is transported from the air-conditioned room to each room (see, for example, Patent Document 1).

WO 19/107163

Measures to prevent infectious diseases are urgently needed. Guidelines have been issued to stipulate two ventilation cycles per hour as a measure to prevent infectious diseases. Here, the ventilation cycle refers to the number of times that all the air in an area (room) is replaced with outside air. If two ventilation cycles were to be achieved using ventilation fans alone, the air volume would be excessive, increasing the air conditioning load and making it difficult to achieve.

This disclosure has been made in light of these circumstances, and its purpose is to provide technology that efficiently ensures ventilation rates.

To solve the above problem, one aspect of the ventilation control system disclosed herein comprises a ventilation device that exchanges air between the inside and outside of a target area, an air conditioning device with a dust collection filter, and a control device that instructs the ventilation device and air conditioning device to operate. The air conditioning device has a circulation air duct that draws in air from the area, purifies it using the dust collection filter, and then blows it out into the area for circulation. The control device instructs the ventilation device and air conditioning device to operate so that the sum of the amount of outside air per unit time introduced by the ventilation device and the amount of return air per unit time circulated through the circulation air duct by the air conditioning device is equal to or greater than a threshold value.

In addition, any combination of the above components, and any conversion of the expression of this disclosure into a method, device, system, recording medium, computer program, etc., are also valid aspects of this disclosure.

This disclosure allows for efficient ventilation rates.

FIG. 1 is a diagram illustrating a configuration of a house according to a first embodiment. FIG. 2 is a diagram illustrating a configuration of a control unit in FIG. 1 . 3A and 3B are diagrams showing the data structure of tables stored in the storage unit of FIG. 10 is a flowchart showing a procedure for determining an air volume by the control device of FIG. 1 . FIG. 10 is a diagram illustrating a configuration of a house according to a second embodiment. 6 is a diagram showing the data structure of a table stored in the storage unit of FIG. 5.

Example 1
Before describing specific embodiments of the present disclosure, an overview of the embodiments will be provided. This embodiment relates to an air conditioning system installed in a facility such as a home that performs whole-building air conditioning for the facility. As described above, as a measure to prevent infectious diseases, the ventilation rate for replacing the air inside the facility with outside air is set at two times per hour. Achieving two ventilation rates using only a ventilation device would be difficult because the air volume would be excessive and the air conditioning load would increase. The air conditioning system according to this embodiment circulates air purified by a HEPA filter within the facility, and replaces a portion of the air volume of the air to be ventilated with the air volume of the circulated air. In other words, ventilation is performed so that the sum of the air volume of the circulated air and the air volume of the ventilated air is equal to or greater than two ventilations per hour. In the following description, air volume refers to the air volume per unit time, for example, per hour.

The examples described below each represent a preferred specific example of the present disclosure. Therefore, the numerical values, shapes, materials, components, component placement and connection configurations, steps (processes), and step order shown in the following examples are merely examples and are not intended to limit the present disclosure. Therefore, among the components in the following examples, any component not described in an independent claim that represents the highest concept of the present disclosure will be described as an optional component. Furthermore, in each figure, substantially identical components are designated by the same reference numerals, and redundant explanations will be omitted or simplified.

Figure 1 shows the configuration of a house 100. The house 100 is equipped with an air conditioning system including a ventilation device 20, an air conditioning device 30, and a control device 40. The air conditioning system is also called a ventilation control system, ventilation system, or central air conditioning system. The house 100 includes a first area 10a and a second area 10b, collectively referred to as areas 10. Areas 10 are, for example, rooms, living rooms, dining rooms, and kitchens. The number of areas 10 included in the house 100 is not limited to two, and the house 100 may also include facilities that include non-residential buildings.

An outside air inlet (not shown) is installed on the exterior wall of the house 100. An outside air duct 50 extends from the outside air inlet toward the interior of the house 100. The outside air duct 50 is also called an outside air intake duct. The outside air duct 50 is connected to the ventilation device 20. An outside air intake fan (not shown) is installed in the ventilation device 20, and as the outside air intake fan rotates, outside air 60 is taken in from the outside air inlet and flows into the ventilation device 20 through the outside air duct 50. The outside air duct 50 extends further from the ventilation device 20 and is connected to a first circulation air duct 54a, allowing the outside air 60 from the ventilation device 20 to flow into the first circulation air duct 54a.

An exhaust air duct 52 is also connected to the ventilation device 20. The exhaust air duct 52 is also called an exhaust duct. The exhaust air duct 52 extends from each area 10 toward the exterior wall of the house 100 via the ventilation device 20. An exhaust port (not shown) is installed in the exterior wall of the house 100, and the exhaust air duct 52 is connected to the exhaust port. The ventilation device 20 exhausts exhaust air 62 through the exhaust air duct 52 through the rotation of an exhaust fan (not shown). In this way, the exhaust air duct 52 collects exhaust air 62 from the first area 10a and the second area 10b and discharges the exhaust air 62 outdoors through a single exhaust port. As a result, the ventilation device 20 ventilates the first area 10a and the second area 10b, which are different from each other, and exchanges air inside and outside the area 10. Heat exchange may also occur in the ventilation device 20.

Inside the house 100, a first circulation air duct 54a extending from each area 10 to the air conditioning device 30 and a second circulation air duct 54b extending from the air conditioning device 30 to each area 10 are installed. The first circulation air duct 54a is also called a return air duct, and the second circulation air duct 54b is also called a supply air duct. The air duct connecting the first circulation air duct 54a and the second circulation air duct 54b is configured in a ring shape.
The circulation air duct 54a and the second circulation air duct 54b are collectively referred to as the circulation air duct 54. Return air 64 from each area 10 flows into the first circulation air duct 54a. As described above, since the first circulation air duct 54a is connected to the outside air duct 50, the return air 64 is mixed with the outside air 60.

A mixture of return air 64 and outside air 60 flows into the air conditioning unit 30 through the first circulation air duct 54a. The air conditioner 32 of the air conditioning unit 30 controls the air conditioning of the mixture of return air 64 and outside air 60. The air conditioner 32 cools or heats the mixture of return air 64 and outside air 60 so that the air temperature reaches a set target temperature. The target temperature is set by the control device 40. The air conditioner 32 may have humidification and dehumidification functions.

Air from the air conditioner 32 flows into a HEPA filter (High Efficiency Particulate Air) 34. The HEPA filter 34 is an air filter that removes dirt, dust, and other particles from the air conditioned by the air conditioner 32, and outputs purified air. The air that passes through the HEPA filter 34 is output as air from the air conditioning unit 30 by a blower (not shown) included in the air conditioning unit 30. The air volume of the blower can be controlled by the control unit 40, which will be described later.

A second circulation air duct 54b is connected to the air conditioning unit 30 so that the air conditioning unit 30 can control the temperature in the first area 10a and the second area 10b. The second circulation air duct 54b extends to the first area 10a and the second area 10b. An air outlet (not shown) is provided in each of the first area 10a and the second area 10b, and each air outlet is connected to the second circulation air duct 54b. The supply air 66 output from the air conditioning unit 30 passes through the second circulation air duct 54b and is blown out from the air outlet into the area 10. A first damper 12a is installed at the air outlet in the first area 10a, and a second damper 12b is installed at the air outlet in the second area 10b. The first damper 12a and the second damper 12b are collectively referred to as damper 12, and the damper 12 adjusts its opening to adjust the volume of supply air 66 blown out from the air outlet into the area 10. The opening degree of the first damper 12a and the second damper 12b is controlled by the control device 40.

Each of the first and second areas 10a and 10b is provided with an intake port (not shown), which is connected to the first circulation air duct 54a. When the air conditioning unit 30 is operating, return air 64 from each area 10 flows from the intake port into the first circulation air duct 54a. The return air 64 is then drawn into the air conditioning unit 30 through the first circulation air duct 54a, as described above. In other words, the circulation air duct 54 allows the air conditioning unit 30 to draw in air from within the area 10, purify it using the HEPA filter 34, and then blow it out into the area 10 for circulation.

A contamination sensor 70 is installed in the first area 10a. The contamination sensor 70 is a sensor for detecting air contamination within the first area 10a, and is, for example, a dust sensor or a gas sensor. Since known technology can be used for the contamination sensor 70, a description thereof will be omitted here. The contamination sensor 70 may also be installed in the second area 10b, or in both the first area 10a and the second area 10b. The contamination sensor 70 has communication capabilities such as wireless communication, and transmits the detected air contamination value to the control device 40.

The control device 40 is a system controller that controls the entire air conditioning system. The control device 40 includes an IF unit 42, a control unit 44, and a memory unit 46. The IF unit 42 is connected to the damper 12, the ventilation device 20, the air conditioning device 30, and the contamination sensor 70 via wireless communication so that they can communicate with each other. Connecting them via wireless communication eliminates the need for complex wiring work. However, at least some of these may be connected via wired communication so that they can communicate with each other. The IF unit 42 receives the air contamination value from the contamination sensor 70.

The control unit 44 determines the control details for the ventilation device 20, air conditioning device 30, and damper 12 based on the received air pollution value. The IF unit 42 transmits control signals containing the determined control details to the ventilation device 20, air conditioning device 30, and damper 12. This is equivalent to instructing the ventilation device 20 and air conditioning device 30 to operate and instructing the opening degree of the damper 12. The memory unit 46 stores predetermined information.

To explain the details of the control device 40, Figure 2 will also be used here. Figure 2 shows the configuration of the control unit 44. The control unit 44 includes a ventilation control unit 200 and an air conditioner control unit 202. The ventilation control unit 200 determines the control details of the ventilation device 20, and the air conditioner control unit 202 determines the control details of the air conditioning unit 30 and damper 12.

The air conditioner control unit 202 receives the air pollution value detected by the pollution sensor 70 from the IF unit 42. The air conditioner control unit 202 determines the return air volume based on the air pollution value by referencing a table stored in the memory unit 46. Figures 3(a)-(b) show the data structure of the table stored in the memory unit 46. As shown in Figure 3(a), pollution values and return air volumes are associated. Here, the larger the pollution value, the larger the return air volume. Figure 3(b) will be described later, returning to Figure 2. The return air volume is the volume of return air 64, and is adjusted by adjusting the air volume of the air conditioning unit 30, adjusting the opening of the damper 12, or a combination of these. For example, the opening of the damper 12 may be a fixed value, and the air volume of the air conditioning unit 30 may be determined according to the determined return air volume. Alternatively, the air volume of the air conditioning unit 30 may be a fixed value, and the opening of the damper 12 may be determined according to the determined return air volume.

The memory unit 46 stores a total airflow setting value to meet a specified value, for example, two ventilations per hour. The ventilation control unit 200 determines the outdoor airflow rate by subtracting the return airflow rate determined by the air conditioner control unit 202 from the total airflow setting value stored in the memory unit 46. The outdoor airflow rate may be greater than the value obtained by subtracting the return airflow rate from the total airflow setting value. The outdoor airflow rate is the airflow rate of outdoor air 60, which is equivalent to the exhaust airflow rate, which is the airflow rate of exhaust air 62. The outdoor airflow rate or exhaust airflow rate is adjusted by adjusting the airflow rate of the ventilation device 20.

The control unit 44 outputs a control signal (hereinafter referred to as the "first control signal") to the IF unit 42 to indicate the airflow rate of the air conditioning unit 30 and the opening degree of the damper 12 determined by the air conditioner control unit 202. The control unit 44 outputs a control signal (hereinafter referred to as the "second control signal") to the IF unit 42 to indicate the airflow rate of the ventilation unit 20 determined by the ventilation control unit 200. The IF unit 42 sends the first control signal to the air conditioning unit 30 and the damper 12, and sends the second control signal to the ventilation unit 20. This is equivalent to instructing the damper 12, ventilation unit 20, and air conditioning unit 30 to operate so that the sum of the amount of outside air per unit time introduced by the ventilation unit 20 and the amount of return air per unit time circulated by the air conditioning unit 30 to the circulation air duct 54 is equal to or greater than a threshold value.

The subject of the device, system, or method disclosed herein includes a computer. The computer executes a program to realize the functions of the subject of the device, system, or method disclosed herein. The computer includes, as its main hardware configuration, a processor that operates according to the program. The type of processor is not important as long as it can realize the functions by executing the program. The processor is composed of one or more electronic circuits, including a semiconductor integrated circuit (IC) or an LSI (Large Scale Integration). The multiple electronic circuits may be integrated into a single chip or may be provided on multiple chips. The multiple chips may be integrated into a single device or may be provided on multiple devices. The program is recorded on a non-transitory recording medium, such as a computer-readable ROM, optical disk, or hard disk drive. The program may be pre-stored on the recording medium or may be supplied to the recording medium via a wide area communication network, including the Internet.

The operation of the air conditioning system configured as described above will now be described. Figure 4 is a flowchart showing the procedure for determining the air volume by the control device 40. The air conditioner control unit 202 acquires a contamination value (S10) and determines the return air volume based on the contamination value (S12). The ventilation control unit 200 determines the outside air volume by subtracting the return air volume from the total air volume setting value (S14).

In this embodiment, the ventilation device 20 and the air conditioning device 30 are instructed to operate so that the sum of the outside air volume per unit time and the return air volume per unit time is equal to or greater than a threshold value, allowing the specified ventilation rate to be shared between the ventilation device 20 and the air conditioning device 30. Also, because the specified ventilation rate is shared between the ventilation device 20 and the air conditioning device 30, the load on the ventilation device 20 can be reduced. Also, because the load on the ventilation device 20 is reduced, the ventilation rate can be efficiently ensured. Also, because the return air volume is determined according to the air pollution level, the return air volume can be secured to reduce the air pollution level. Also, because the outside air volume is determined based on the return air volume, the ventilation rate can be efficiently secured while reducing the air pollution level.

An overview of one aspect of the present disclosure is as follows. A ventilation control system according to one aspect of the present disclosure includes a ventilation device (20) that exchanges air between the inside and outside of a target area, an air conditioner (30) having a dust collection filter (34), and a control device (40) that instructs the ventilation device (20) and the air conditioner (30) to operate. The air conditioner (30) has a circulation air duct (54) that draws in air from the area, purifies it using the dust collection filter (34), and then blows it into the area for circulation. The control device (40) instructs the ventilation device (20) and the air conditioner (30) to operate so that the sum of the volume of outside air per unit time introduced by the ventilation device (20) and the volume of return air per unit time circulated through the circulation air duct (54) by the air conditioner (30) is equal to or greater than a threshold value.

The dust collection filter (34) may be a HEPA (High Efficiency Particulate Air) filter (34).

The control device (40) may include a ventilation control unit (200) that controls the ventilation device (20) and an air conditioner control unit (202) that controls the air conditioning device (30). The air conditioner control unit (202) receives the air pollution value detected by the pollution sensor (70) and determines the return air volume in accordance with the air pollution value, and the ventilation control unit (200) may determine the outside air volume based on the return air volume determined by the air conditioner control unit (202).

Example 2
Next, a second embodiment will be described. Like the first embodiment, the second embodiment relates to an air conditioning system that performs whole-building air conditioning for a facility. In the first embodiment, the return air volume is determined based on the air pollution value, and then the outdoor air volume is determined based on the return air volume. In the second embodiment, the outdoor air volume is determined based on the CO2 concentration, and then the return air volume is determined based on the outdoor air volume. The following description will focus on the differences from the first embodiment.

Figure 5 is a diagram showing the configuration of the house 100. Figure 5 is similar to Figure 1. A first CO2 sensor 72a is disposed in the first area 10a, and a second CO2 sensor 72b is disposed in the second area 10b. The first CO2 sensor 72a and the second CO2 sensor 72b are collectively referred to as CO2 sensors 72. Each CO2 sensor 72 is a sensor for detecting the CO2 concentration within the area 10, and as known technology may be used for the CO2 sensors 72, a description thereof will be omitted here. Each CO2 sensor 72 has communication capabilities such as wireless communication, and transmits the detected CO2 concentration to the control device 40.

The ventilation control unit 200 of the control device 40 shown in Figure 2 receives the CO2 concentrations detected by each of the multiple CO2 sensors 72 from the IF unit 42. The ventilation control unit 200 selects the maximum CO2 concentration from the multiple CO2 concentrations. The ventilation control unit 200 determines the outdoor air volume based on the maximum CO2 concentration by referencing a table stored in the memory unit 46. As shown in Figure 3 (b), the CO2 concentration and outdoor air volume are associated. Here, the outdoor air volume is increased as the CO2 concentration increases. Return to Figure 2.

The memory unit 46 stores a total airflow setting value that satisfies a specified value, for example, two ventilations per hour. The air conditioner control unit 202 determines the return airflow rate by subtracting the outside airflow rate determined by the ventilation control unit 200 from the total airflow setting value stored in the memory unit 46. The return airflow rate may be greater than the value obtained by subtracting the outside airflow rate from the total airflow setting value.

In FIG. 5, each CO2 sensor 72 is installed in an area 10. However, one CO2 sensor 72 may be installed near the exhaust port of the exhaust air duct 52. In this case, the CO2 sensor 72 detects the CO2 concentration near the exhaust port. The ventilation control unit 200 determines the outside air volume based on the CO2 concentration from the CO2 sensor 72. In this case, even if there are differences in CO2 concentration between areas 10, the differences are equalized by the air conditioning unit 30.

The control unit 44 of the control device 40 in Figure 5 may also estimate the number of people occupying the area 10 based on the received CO2 concentration by referencing a table stored in the memory unit 46. Figure 6 shows the data structure of the table stored in the memory unit 46. As shown, CO2 concentration corresponds to the number of people occupying the area. Here, the higher the CO2 concentration, the higher the number of people occupying the area. The ventilation control unit 200 in Figure 2 receives the estimated number of people occupying the area from the control unit 44. The ventilation control unit 200 determines the outdoor air volume according to the number of people occupying the area so that the outdoor air volume increases as the number of people occupying the area increases. The same applies to determining the return air volume.

In this embodiment, the outdoor air volume is determined according to the CO2 concentration, ensuring the outdoor air volume necessary to reduce the CO2 concentration. Furthermore, the return air volume is determined based on the outdoor air volume, ensuring an efficient ventilation rate while reducing the CO2 concentration. Furthermore, the outdoor air volume is determined according to the maximum CO2 concentration among the CO2 concentrations detected by each of the multiple CO2 sensors 72, making it possible to reduce the CO2 concentration in each area 10. Furthermore, the outdoor air volume is determined according to the number of people present in the room, ensuring the outdoor air volume necessary to reduce the CO2 concentration.

An overview of one aspect of the present disclosure is as follows. The control device (40) may include a ventilation control unit (200) that controls the ventilation device (20) and an air conditioner control unit (202) that controls the air conditioning device (30). The ventilation control unit (200) may receive the indoor CO2 concentration detected by the CO2 sensor (72) and determine the outdoor air volume in accordance with the CO2 concentration, and the air conditioner control unit (202) may determine the return air volume based on the outdoor air volume determined by the ventilation control unit (200).

The area may include multiple rooms. A CO2 sensor (72) may be installed in each room, and the ventilation control unit (200) may determine the outside air volume according to the maximum CO2 concentration among the CO2 concentrations detected by each of the multiple CO2 sensors (72).

The control device (40) may include a ventilation control unit (200) that controls the ventilation device (20) and an air conditioner control unit (202) that controls the air conditioning device (30). The ventilation control unit (200) may receive the estimated number of people in the area and determine the outdoor air volume according to the number of people in the area, and the air conditioner control unit (202) may determine the return air volume based on the outdoor air volume determined by the ventilation control unit (200).

The present disclosure has been described above based on examples. These examples are merely illustrative, and those skilled in the art will understand that various modifications are possible in the combination of each component or each treatment process, and that such modifications are also within the scope of the present disclosure.

In Examples 1 and 2, the memory unit 46 is included in the control device 40. However, this is not limiting; for example, the memory unit 46 may be connected to the control device 40 as a storage device. This modification allows for greater flexibility in configuration.

10 Area, 12 Damper, 20 Ventilation device, 30 Air conditioning device, 32 Air conditioner, 34 HEPA filter (dust collection filter), 40 Control device, 42 IF unit, 44 Control unit, 46 Memory unit, 50 Outdoor air duct, 52 Exhaust air duct, 54 Circulation air duct, 60 Outdoor air, 62 Exhaust air, 64 Return air, 66 Supply air, 70 Dirt sensor, 72 CO2 sensor, 100 House, 200 Ventilation control unit, 202 Air conditioner control unit.

Claims (3)

A ventilation system that exchanges air between the inside and outside of the area in question;
an air conditioning device having a dust collection filter;
a control device that instructs the ventilation device and the air conditioning device to operate;
the air conditioning device has a circulation air duct that draws in air within the area, purifies the air using the dust collection filter, and then blows the air into the area to circulate it;
The control device controls the amount of outside air per unit time introduced by the ventilation device and the amount of return air per unit time passed through a dust collection filter by the air conditioning device and circulated to the circulation air duct,
A ventilation control system that instructs the ventilation device and the air conditioning device to operate so that a portion of the ventilation air volume, which is the amount of air that should be replaced with outside air in a target area for a specified ventilation frequency, is replaced with the return air volume, and the remainder of the ventilation air volume becomes the outside air volume. A ventilation system that exchanges air between the inside and outside of the area in question;
an air conditioning device having a dust collection filter;
a control device that instructs the ventilation device and the air conditioning device to operate;
the air conditioning device has a circulation air duct that draws in air within the area, purifies the air using the dust collection filter, and then blows the air into the area to circulate it;
The control device controls the amount of outside air per unit time introduced by the ventilation device and the amount of return air per unit time passed through a dust collection filter by the air conditioning device and circulated to the circulation air duct,
A ventilation control system that instructs the ventilation device and the air conditioning device to operate so that a portion of the ventilation air volume, which is the amount of air that should be replaced with outside air in a target area for a specified ventilation frequency, is replaced with the outside air volume, and the remainder of the ventilation air volume becomes the return air volume. 3. The ventilation control system according to claim 1, wherein the dust collection filter is a HEPA (High Efficiency Particulate Air) filter.