Air conditioning system, building, and program recording medium

Abstract

An air conditioning system (1) includes: an air conditioning device (10) having air supply and exhaust functions and an indoor temperature adjustment function, which performs air conditioning of an indoor space (80); a CO2 sensor (20) disposed at a position (P0) in the indoor space (80), which measures a first concentration of carbon dioxide at the position (P0); a signal processing section (32) which estimates a second concentration of carbon dioxide at each of one or more positions (P1 and P2) different in height from the position (P0) from a floor surface or a ceiling surface of the indoor space (80), based on the first concentration measured by the CO2 sensor (20); and a control section (33) which controls the air conditioning device (10) based on the first concentration and the second concentration.

Description

Technical Field

[0001] This invention relates to an air conditioning system, a building, and a program recording medium. Background Technology

[0002] For example, Patent Document 1 discloses an air conditioning system comprising an air conditioner and a ventilation device. In the air conditioning system disclosed in Patent Document 1, when the carbon dioxide concentration (hereinafter referred to as CO2 concentration) detected by the carbon dioxide sensor of the air conditioner or ventilation device is greater than a set concentration, the ventilation device is controlled to increase the ventilation rate.

[0003] Existing technical documents

[0004] Patent documents

[0005] Patent Document 1: International Publication No. 2014 / 109193 Summary of the Invention

[0006] The problem the invention aims to solve

[0007] The CO2 concentration in an indoor space can vary locally depending on the density of people. Therefore, in conventional air conditioning systems, the following situation may occur: although the overall CO2 concentration in the indoor space is low and ventilation is not required, the ventilation device will operate due to locally high CO2 concentrations at locations where carbon dioxide sensors are installed, thus consuming unnecessary electricity.

[0008] Conversely, the following situation may occur: although the CO2 concentration is high in the overall indoor space and ventilation is necessary, the ventilation device may not work because the CO2 concentration is locally low at the location where the carbon dioxide sensor is installed. In this case, the CO2 concentration cannot be reduced, and therefore the comfort of the indoor space cannot be maintained.

[0009] Therefore, the object of the present invention is to provide an air conditioning system, a building, and a program recording medium that can maintain the comfort of an indoor space while suppressing the power consumption of air conditioning equipment.

[0010] Solution for solving the problem

[0011] An air conditioning system according to one aspect of the present invention comprises: an air conditioning unit having air supply and exhaust functions and an indoor temperature adjustment function for regulating the air in an indoor space; a CO2 sensor disposed at a first location in the indoor space for measuring a first concentration of carbon dioxide at the first location; a signal processing unit for estimating a second concentration of carbon dioxide at each of one or more second locations based on the first concentration measured by the CO2 sensor, wherein the height of the second location from the floor or ceiling of the indoor space is different from the height of the first location from the floor or ceiling; and a control unit for controlling the air conditioning unit based on the first concentration and the second concentration.

[0012] One embodiment of the present invention relates to a building equipped with the aforementioned air conditioning system.

[0013] One aspect of the present invention involves a program recording medium that enables a computer to execute a control method for controlling an air conditioning device, the air conditioning device having air supply and exhaust functions and indoor temperature adjustment functions, for regulating the air in an indoor space. In the control method, a first concentration of carbon dioxide at a first location is obtained from a CO2 sensor located at a first location in the indoor space. Based on the first concentration, a second concentration of carbon dioxide at each of one or more second locations is estimated, wherein the height of the second location from the floor or ceiling of the indoor space is different from the height of the first location from the floor or ceiling. The air conditioning device is controlled based on the first concentration and the second concentration.

[0014] Alternatively, the present invention can also be implemented as the control method described above. Or, the present invention can also be implemented as a computer-readable, non-transitory recording medium containing the above-described program.

[0015] The effects of the invention

[0016] According to the present invention, it is possible to maintain the comfort of the indoor space while suppressing the power consumption of the air conditioning equipment. Attached Figure Description

[0017] Figure 1 This is a diagram showing the structure of the air conditioning system according to Embodiment 1.

[0018] Figure 2 This is a flowchart illustrating the operation of the air conditioning system according to Embodiment 1.

[0019] Figure 3 This is a diagram showing the structure of the air conditioning system according to Embodiment 2.

[0020] Figure 4AIt is a 3D view showing the location of a person and multiple CO2 sensors in an indoor space.

[0021] Figure 4B It is shown Figure 4A The image shows a contour map of CO2 concentration distribution on the ceiling surface (sensor mounting surface) of the indoor space.

[0022] Figure 5 This is a flowchart illustrating the operation of the air conditioning system according to Embodiment 2.

[0023] Figure 6A This is a perspective view showing a first example of a configuration of multiple CO2 sensors.

[0024] Figure 6B This is a perspective view showing a second example of a configuration of multiple CO2 sensors.

[0025] Figure 6C This is a perspective view showing a third example of a configuration of multiple CO2 sensors.

[0026] Figure 7A This is a top view showing the shape of the interior space and the configuration of multiple CO2 sensors, representing a first example.

[0027] Figure 7B This is a top view showing the shape of the indoor space and the configuration of multiple CO2 sensors, a second example.

[0028] Figure 7C This is a top view of a third example showing the shape of the indoor space and the configuration of multiple CO2 sensors.

[0029] Figure 7D This is a top view of a fourth example showing the shape of the indoor space and the configuration of multiple CO2 sensors.

[0030] Figure 7E This is a top view of the fifth example, showing the shape of the indoor space and the configuration of multiple CO2 sensors.

[0031] Figure 7F This is a top view of the sixth example, showing the shape of the indoor space and the configuration of multiple CO2 sensors.

[0032] Figure 8 This is a diagram showing the structure of the air conditioning system according to Embodiment 3.

[0033] Figure 9 It is a graph showing the change in CO2 concentration over time.

[0034] Figure 10 This is a flowchart illustrating the operation of the air conditioning system according to Embodiment 3.

[0035] Figure 11 This is a diagram showing the structure of the air conditioning system according to Embodiment 4.

[0036] Figure 12 This is a diagram showing the structure of the information presentation unit according to Embodiment 4. Detailed Implementation

[0037] Below, the air conditioning system, building, and program recording medium according to embodiments of the present invention will be described in detail using the accompanying drawings. Furthermore, the embodiments described below illustrate specific examples of the present invention. Therefore, the numerical values, shapes, materials, structural elements, the arrangement and connection methods of structural elements, steps, and the order of steps shown in the following embodiments are merely examples and are not intended to limit the present invention. Therefore, structural elements in the following embodiments not described in the independent claims will be described as arbitrary structural elements.

[0038] Furthermore, these figures are schematic diagrams and may not be strictly representational. Therefore, for example, the scales may not be consistent across figures. Additionally, substantially identical structures are labeled with the same symbols across figures, and repetitive descriptions are omitted or simplified.

[0039] Furthermore, in this specification, terms such as parallel or perpendicular indicating the relationship between elements, terms such as rectangle, square or circle indicating the shape of elements, and numerical ranges are not merely expressions with a strict meaning, but also imply expressions that include substantially equivalent ranges, such as expressions of differences of a few percent or so.

[0040] In this specification and accompanying drawings, the x-axis, y-axis, and z-axis represent the three axes of a three-dimensional orthogonal coordinate system. In each embodiment, the z-axis direction is set as the vertical direction, and the direction perpendicular to the z-axis (parallel to the xy-plane) is set as the horizontal direction. Furthermore, the positive direction of the z-axis is set as vertically upward.

[0041] (Implementation Method 1)

[0042] [structure]

[0043] First, use Figure 1 The structure of the air conditioning system involved in Implementation Method 1 will be described. Figure 1 This is a diagram showing the structure of the air conditioning system 1 according to this embodiment.

[0044] Figure 1The air conditioning system 1 shown is a system for adjusting the air environment of an indoor space 80 in a building such as a residence, office, or hospital. The indoor space 80 is a rectangular enclosed space with a ceiling 81 and a floor 82. For example, the indoor space 80 is a large space with a floor 82 size of 15m × 15m and a height of about 2.5m to 3.0m from the floor 82 to the ceiling 81.

[0045] The air environment of indoor space 80 refers to the temperature, humidity, and CO2 concentration within indoor space 80. Air conditioning system 1 adjusts at least one of the temperature and humidity of indoor space 80, and also adjusts the CO2 concentration of indoor space 80.

[0046] like Figure 1 As shown, the air conditioning system 1 includes an air conditioning unit 10, a CO2 sensor 20, a control device 30, and a cloud server 40. The control device 30 and the cloud server 40 are connected in a way that enables communication via a wide area communication network 50 such as the Internet.

[0047] The air conditioning unit 10 has air supply and exhaust functions as well as indoor temperature adjustment functions, for conditioning the air in the indoor space 80. Specifically, the air conditioning unit 10 includes an air supply device 11 and an exhaust device 12. The air supply device 11 is a device for supplying air from the outdoor space to the indoor space 80. The exhaust device 12 is a device for exhausting air from the indoor space 80 to the outdoor space. The air supply device 11 and the exhaust device 12 can be, for example, blowers (fans). The air supply device 11 and the exhaust device 12 can also be single devices with air supply and exhaust functions.

[0048] In addition, the air conditioning unit 10 also includes an indoor temperature regulating device (not shown) for adjusting the temperature of the indoor space 80. The indoor temperature regulating device may be, for example, a cooling or heating device that adjusts the temperature of the indoor space 80. The indoor temperature regulating device may also adjust the humidity of the indoor space 80. Furthermore, the indoor temperature regulating device may be a cooling device with only cooling function, or a heating device with only heating function. Alternatively, the air conditioning unit 10 may be a single device (e.g., a total heat exchanger) that has the functions of an air supply device 11, an exhaust device 12, and both cooling and heating functions.

[0049] CO2 sensor 20 is positioned at location P0 within the indoor space 80 to measure the CO2 concentration at location P0. The CO2 concentration measured by CO2 sensor 20 is an example of a first concentration and is a measured value of CO2 concentration. CO2 sensor 20 is, for example, an infrared absorption CO2 sensor, but is not particularly limited. CO2 sensor 20 outputs information indicating the measured CO2 concentration to control device 30.

[0050] The location of the CO2 sensor 20, i.e., location P0, is an example of the first location within the indoor space 80, such as on the ceiling surface 81. Figure 1 As shown, position P0 is a location closer to one of the four corners than the center of the ceiling surface 81. For example, position P0 is a location where there are rarely any people 90 directly below it. That is, position P0 is not directly above the chair where person 90 sits, the work area of ​​person 90, or the door near where person 90 enters or exits the room space 80.

[0051] Furthermore, the location P0 of the CO2 sensor 20 can also be the ground 82. Alternatively, location P0 can also be a position at a specified distance in the vertical direction from the ceiling surface 81 or the ground 82.

[0052] The control device 30 controls the air conditioning unit 10 based on the CO2 concentration measured by the CO2 sensor 20. The control device 30 is a local controller installed in or near the indoor space 80. The control device 30 includes a first communication unit 31, a signal processing unit 32, a control unit 33, a storage unit 34, and a second communication unit 35.

[0053] The first communication unit 31 is a communication module (communication circuit) used by the control device 30 to communicate with the air conditioning unit 10 and the CO2 sensor 20 via a local communication network. The first communication unit 31 acquires, for example, operational information of the air conditioning unit 10. Specifically, the operational information includes information indicating the operating status of the air conditioning unit 10, such as set temperature, set humidity, or set air supply / discharge rate. Additionally, the first communication unit 31 acquires the CO2 concentration at position P0 from the CO2 sensor 20. Communication performed by the first communication unit 31 can be either wired or wireless. There are no particular limitations on the communication standard used in the communication.

[0054] The signal processing unit 32 estimates the CO2 concentration at one or more locations different from location P0 based on the CO2 concentration measured by the CO2 sensor 20. The CO2 concentration estimated by the signal processing unit 32 is an example of a second concentration and is an estimated value of the CO2 concentration. In this embodiment, the signal processing unit 32 estimates the CO2 concentration at a location different from the measurement location P0 at the same time as the CO2 concentration measured by the CO2 sensor 20.

[0055] For example, the signal processing unit 32 estimates Figure 1The CO2 concentrations at locations P1 and P2 are shown. Both locations P1 and P2 are examples of second locations at a different height from the ground 82 or ceiling surface 81 than location P0. Location P1 is 1.2 m above the ground 82. The height of location P1 corresponds to the same height as the mouth of a person sitting in a chair 90. Location P2 is on the ground 82. Both locations P1 and P2 are distinct positions on the vertical line VL passing through location P0.

[0056] In this embodiment, the signal processing unit 32 utilizes the fact that the CO2 concentration at each of positions P1 and P2 can be represented as a linear function with the CO2 concentration at position P0 as the variable. Specifically, the signal processing unit 32 estimates the CO2 concentration based on the following equation (1).

[0057] (1) B = α × A + β

[0058] In equation (1), A is the CO2 concentration measured by CO2 sensor 20, i.e., the measured value of CO2 concentration at position P0. B is the estimated value of CO2 concentration at position P1 or P2. A and β are coefficients. Specifically, α and β are values ​​that may vary depending on the position at which the estimation is performed.

[0059] For example, α becomes a smaller value when estimated at a position close to the ground 82 than when estimated at a position close to the ceiling 81. This is derived by considering the movement path of carbon dioxide contained in the exhaled breath of person 90. Specifically, the carbon dioxide contained in the exhaled breath of person 90 is as follows: Figure 1 As shown, carbon dioxide moves towards the ceiling surface 81 due to the updraft 91 generated by the body temperature of person 90. Carbon dioxide reaches the ceiling surface 81 directly above person 90, then diffuses along the ceiling surface 81, and, because carbon dioxide is heavier than air, slowly descends and diffuses throughout the indoor space 80. On the other hand, with a person present indoors, due to the frequent rise of carbon dioxide around the person, the CO2 concentration is higher closer to the ceiling surface 81 and lower closer to the ground 82.

[0060] Furthermore, at a height near the mouth of person 90 (position P1), carbon dioxide exhaled by person 90 may be present, as if person 90 were nearby. Therefore, the CO2 concentration at position P1 may sometimes be higher than the CO2 concentration at the ceiling surface 81. Based on the above, for example, when calculating the CO2 concentration B at position P1, α is a value of 0.9 or higher and 1.5 or lower. Similarly, when calculating the CO2 concentration B at position P2, α is a value of 0.6 or higher and 0.9 or lower. α and β can also be varied based on the distance of positions P1 and P2 from person 90.

[0061] Furthermore, the signal processing unit 32 may estimate the CO2 concentration at only one location. For example, the signal processing unit 32 may estimate the CO2 concentration at only location P2. Alternatively, the signal processing unit 32 may continuously estimate the CO2 concentration along the vertical line VL. That is, it may also estimate the CO2 concentration at each of multiple locations arranged at sufficiently small equal intervals (e.g., less than 10 cm) along the vertical line VL. Thus, a distribution of CO2 concentration along the vertical line VL (i.e., a vertical distribution) can be generated.

[0062] The signal processing unit 32 can be a processor, a microcomputer, or a dedicated circuit. The signal processing unit 32 can also be implemented using a combination of two or more of these components. The functions performed by the signal processing unit 32 can be implemented using either software or hardware.

[0063] The control unit 33 controls the air conditioning unit 10 based on the CO2 concentration A measured by the CO2 sensor 20 and multiple CO2 concentrations B estimated by the signal processing unit 32. Specifically, if at least one of the CO2 concentration A and the multiple CO2 concentrations B exceeds a predetermined threshold Dth, the control unit 33 controls the air conditioning unit 10 in a manner that prioritizes the air supply and exhaust functions over the indoor temperature adjustment functions.

[0064] The threshold Dth is the baseline value that the CO2 concentration in an indoor space should not exceed; that is, the permissible concentration of CO2. The threshold Dth is a value greater than 400 ppm and less than 2000 ppm. The threshold Dth can also be a value greater than 700 ppm and less than 1000 ppm. As an example, the threshold Dth is 1000 ppm.

[0065] The control unit 33 determines the control conditions for the air conditioning device 10 based on capability information indicating the capabilities of the air conditioning device 10, and outputs control commands to the air conditioning device 10 via the first communication unit 31, causing the air conditioning device 10 to operate under the determined control conditions. Furthermore, the capability information may be obtained from the air conditioning device 10 via the first communication unit 31, or alternatively, the capability information may be obtained from the cloud server 40 via the second communication unit 35.

[0066] The control unit 33 can be a processor, a microcomputer, or a dedicated circuit. The control unit 33 can also be implemented using a combination of two or more of these components. The functions performed by the control unit 33 can be implemented using either software or hardware. The control unit 33 and the signal processing unit 32 can also be implemented by sharing the same hardware.

[0067] The storage unit 34 is a storage device that stores programs for estimating CO2 concentration and programs for controlling the air conditioning equipment 10. The storage unit 34 is, for example, a non-volatile storage element such as a semiconductor memory.

[0068] The second communication unit 35 is a communication module (communication circuit) used by the control device 30 to communicate with the cloud server 40 via the wide area communication network 50. The communication performed by the second communication unit 35 can be either wireless or wired communication.

[0069] The cloud server 40 is a computer system that stores time-series data of CO2 concentration measured by the CO2 sensor 20. It is shown that after the information on the CO2 concentration measured by the CO2 sensor 20 is acquired by the first communication unit 31 of the control device 30, it is sent to the cloud server 40 via the second communication unit 35. In the cloud server 40, the CO2 concentration, along with the time, is stored as time-series data. Alternatively, the time-series data of the CO2 concentration can also be stored in the storage unit 34 of the control device 30. In this case, the control device 30 may not have the second communication unit 35, and the air conditioning system 1 may not have the cloud server 40.

[0070] [action]

[0071] Next, use Figure 2 The operation of the air conditioning system 1 according to this embodiment will be explained. Figure 2 This is a flowchart illustrating the operation of the air conditioning system 1 according to this embodiment. Figure 2 This mainly shows the operation of the control device 30.

[0072] like Figure 2 As shown, firstly, the control unit 33 acquires the air supply and exhaust function capability information of the air conditioning unit 10 (S10). At this time, the control unit 33 can also acquire the operation information of the air conditioning unit 10. The control unit 33 can appropriately determine the control conditions of the air conditioning unit 10 by comparing the operation information of the air conditioning unit 10 with the capability information.

[0073] Next, the signal processing unit 32 acquires the measured value of CO2 concentration from the CO2 sensor 20 via the first communication unit 31 (S11). The CO2 sensor 20 measures the CO2 concentration at position P0, for example, based on an instruction from the control unit 33, and outputs information indicating the measured CO2 concentration to the control device 30. Alternatively, the CO2 sensor 20 may continuously or periodically measure the CO2 concentration and continuously or periodically output the measured CO2 concentration.

[0074] Next, the signal processing unit 32 calculates the vertical distribution D(z) of the CO2 concentration (S12). The vertical distribution D(z) is shown... Figure 1 The estimated CO2 concentrations at multiple locations on the vertical line VL are shown. The signal processing unit 32 uses α and β, appropriately determined for each estimated location, and estimates the CO2 concentration at each location based on the above equation (1). The estimated vertical distribution D(z) is temporarily stored, for example, in the storage unit 34.

[0075] Next, the signal processing unit 32 extracts the maximum concentration Dmax, which has the highest CO2 concentration, from the vertical distribution D(z) (S13). The signal processing unit 32 compares the extracted maximum concentration Dmax with a predetermined threshold Dth (S14).

[0076] When the maximum concentration Dmax is below the threshold Dth ("Yes" in S14), the control unit 33 maintains the current control conditions of the air conditioning equipment 10 (S15). That is, since the CO2 concentration at any position on the vertical line VL does not exceed the threshold Dth, the CO2 concentration in the indoor space 80 is within the allowable range, and the control conditions do not need to be changed.

[0077] If the maximum concentration Dmax exceeds the threshold Dth (No in S14), the control unit 33 determines the control conditions for making the maximum concentration Dmax below the threshold Dth based on the capability information (S16). For example, the control unit 33 calculates the required exhaust gas flow rate to make the maximum concentration Dmax below the threshold Dth and determines the control conditions for achieving the calculated exhaust gas flow rate. Furthermore, since the capability information is used to determine the control conditions, the acquisition of capability information (S10) can also be performed after determining that the maximum concentration Dmax exceeds the threshold Dth.

[0078] Next, the control unit 33 controls the air conditioning unit 10 in a manner that prioritizes the air supply and exhaust functions over the indoor temperature adjustment function (S17). Specifically, the control unit 33 operates the air supply device 11 and the exhaust device 12 based on the control conditions determined in step S16.

[0079] Then, the control device 30 repeats the process from step S11. Thus, it is possible to rapidly reduce the CO2 concentration in the indoor space 80 if the CO2 concentration exceeds the threshold Dth, thereby maintaining the comfort of the indoor space 80.

[0080] Furthermore, in step S12, the signal processing unit 32 can also estimate the CO2 concentration at only one of positions P1 and P2. In this case, step S13 is omitted.

[0081] [Effects, etc.]

[0082] As described above, the air conditioning system 1 according to this embodiment includes: an air conditioning unit 10, which has air supply and exhaust functions and indoor temperature adjustment functions to regulate the air in an indoor space; a CO2 sensor 20, which is installed at a first position in the indoor space 80 to measure a first concentration of carbon dioxide at the first position; a signal processing unit 32, which estimates a second concentration of carbon dioxide at each of one or more second positions based on the first concentration measured by the CO2 sensor 20, wherein the height of the second position from the ground 82 or ceiling surface 81 of the indoor space 80 is different from the height of the first position from the ground 82 or ceiling surface 81; and a control unit 33, which controls the air conditioning unit 10 based on the first and second concentrations.

[0083] Therefore, by controlling the air conditioning unit 10 based on the CO2 concentration at two or more locations within the indoor space 80, the effects of localized variations in CO2 concentration (i.e., uneven concentration) within the indoor space 80 can be suppressed, enabling the air conditioning unit 10 to operate efficiently. Consequently, the comfort of the indoor space 80 can be maintained while suppressing the power consumption of the air conditioning unit 10.

[0084] Furthermore, a large number of CO2 sensors are unnecessary; only one CO2 sensor 20 is required as a minimal structure. On the other hand, while a large number of CO2 sensors can generate a highly accurate spatial distribution of CO2 concentration within the indoor space 80, this approach introduces the side effects of increased complexity and cost in processing the CO2 concentration data obtained from numerous sensors. In contrast, the air conditioning system 1 according to this embodiment can operate the air conditioning unit 10 efficiently with a minimal number of sensors. Of course, in cases where complex airflow due to the indoor shape or air supply / exhaust results in multiple areas with large air gaps, additional CO2 sensors 20 can be installed on the ceiling surface corresponding to those areas.

[0085] Furthermore, if ventilation is performed while the air conditioning unit 10 is adjusting the temperature or humidity within the indoor space 80, the temperature or humidity of the indoor space 80 will change, potentially compromising the comfort of the person 90 located in the indoor space 80. To avoid compromising comfort, the temperature or humidity needs to be adjusted quickly. In this situation, the power consumption of the air conditioning unit 10 increases as it operates its indoor temperature adjustment function more efficiently.

[0086] According to the air conditioning system 1 of this embodiment, the air conditioning unit 10 is controlled based on the CO2 concentration in the indoor space 80. Therefore, ventilation can be performed when needed and not performed when not needed. For example, if the CO2 concentration is maintained at a low level, the number of ventilations can be less than the normal number of ventilations, i.e., 0.5 times / hour. Thus, the comfort of the indoor space can be maintained while suppressing the power consumption of the air conditioning unit 10.

[0087] Furthermore, since the air supply device 11 and the exhaust device 12 can be controlled frequently, the amount of air exchanged each time can be reduced. By reducing the amount of air exchanged, it is easier to maintain a constant temperature or humidity in the indoor space 80, thus ensuring stable operation of the indoor temperature adjustment function. In other words, because the temperature or humidity fluctuations are smaller, the output of the indoor temperature adjustment function can also be reduced, thereby suppressing power consumption.

[0088] Additionally, for example, the measurement location, i.e., the first location, determined by the CO2 sensor 20, is located on the ceiling surface 81 or the ground surface 82.

[0089] Therefore, the CO2 sensor 20 can be positioned away from the mouth of the person 90. This suppresses sharp fluctuations in the CO2 concentration measured by the CO2 sensor 20 due to the person 90's breathing, improving the reliability of the measured values. Consequently, the reliability of the estimated CO2 concentration based on the measured values ​​is also improved. Thus, the effects of uneven concentration within the indoor space 80 can be suppressed, allowing the air conditioning equipment 10 to operate efficiently.

[0090] Furthermore, since the CO2 sensor 20 is installed on the ceiling surface 81, the possibility of it coming into contact with people 90, objects, or water is low. Therefore, the possibility of the CO2 sensor 20 malfunctioning is also low, enabling a highly reliable air conditioning system 1.

[0091] Furthermore, in the air conditioning system 1, the CO2 concentration distribution within the indoor space 80 can be generated with high precision by constructing and simulating a physical model of airflow using fluid dynamics. However, this not only increases the computational load but also requires reconstructing the physical model every time a person 90 enters or leaves the indoor space 80. Therefore, it is difficult to efficiently control the air conditioning equipment 10 in accordance with the actual conditions within the indoor space 80.

[0092] In contrast, in the air conditioning system 1 according to this embodiment, for example, when the first concentration is set to A and the second concentration is set to B, the signal processing unit 32 estimates the second concentration based on the formula: B=α×A+β (α and β are coefficients).

[0093] Therefore, complex and computationally intensive calculations can be avoided, thus reducing the amount of computation required to efficiently control the air conditioning equipment 10.

[0094] Additionally, for example, the measurement position, i.e., the first position, measured by the CO2 sensor 20, is located on the ceiling surface 81, and the more than one second position is a plurality of different second positions on a vertical line VL passing through the first position.

[0095] Therefore, by increasing the number of estimated CO2 concentration values, the effects of uneven concentration within the indoor space 80 can be further suppressed, enabling the air conditioning equipment 10 to operate more efficiently.

[0096] Additionally, for example, if at least one of the first concentration and one or more second concentrations exceeds a predetermined threshold Dth, the control unit 33 controls the air conditioning unit 10 in such a way that the supply and exhaust functions take precedence over the indoor temperature adjustment functions.

[0097] Therefore, the air conditioning unit 10 can be activated to rapidly reduce the CO2 concentration when the CO2 concentration exceeds the threshold Dth. This maintains the comfort of the indoor space 80. For example, if the CO2 concentration in the indoor space 80 cannot be reduced by operating at a normal air exchange rate of 0.5 times / hour, the air supply and exhaust functions can be prioritized, thus rapidly reducing the CO2 concentration in the indoor space 80.

[0098] Additionally, for example, the program involved in this embodiment is a program that causes a computer to execute a control method for controlling an air conditioning device 10, which has air supply and exhaust functions and indoor temperature adjustment functions, to regulate the air in an indoor space 80. In the control method, a first concentration of carbon dioxide at a first location is obtained from a CO2 sensor 20 installed at a first location in the indoor space 80. Based on the first concentration, a second concentration of carbon dioxide at each of one or more second locations is estimated, wherein the height of the second location from the ground 82 or ceiling surface 81 of the indoor space 80 is different from the height of the first location from the ground 82 or ceiling surface 81. The air conditioning device 10 is controlled based on the first and second concentrations.

[0099] Therefore, similar to the case of air conditioning system 1, it is possible to maintain the comfort of indoor space 80 while suppressing the power consumption of air conditioning equipment 10.

[0100] (Implementation Method 2)

[0101] Next, implementation method 2 will be described.

[0102] In Embodiment 2, the main difference from Embodiment 1 is that a person detection sensor and multiple CO2 sensors are installed in the indoor space. The following description focuses on the differences from Embodiment 1, omitting or simplifying explanations of commonalities.

[0103] [structure]

[0104] First, use Figure 3 The structure of the air conditioning system involved in Implementation Method 2 will be described. Figure 3 This is a diagram showing the structure of the air conditioning system 101 according to this embodiment.

[0105] like Figure 3 As shown, the air conditioning system 101 includes an air conditioning unit 10, multiple CO2 sensors 20a-20e, a human detection sensor 120, a control device 130, and a cloud server 40.

[0106] The multiple CO2 sensors 20a to 20e are all the same as the CO2 sensor 20 according to Embodiment 1. The installation positions of the multiple CO2 sensors 20a to 20e are different from each other. In the following description, when it is not necessary to distinguish between CO2 sensors 20a to 20e, such as when describing the common features of each CO2 sensor, the description will sometimes refer to them as CO2 sensor 20.

[0107] Increasing the number of CO2 sensors 20 allows for a more accurate generation of the CO2 concentration distribution in the indoor space 80, but it also inevitably increases the computational load. Therefore, it is best to have a smaller number of CO2 sensors 20. In the air conditioning system 101 of this embodiment, by focusing on the configuration of the CO2 sensors 20, the influence of uneven concentration in the indoor space 80 is suppressed using a limited number of CO2 sensors 20.

[0108] Specifically, multiple CO2 sensors 20 are located within a first virtual plane parallel to the ceiling surface 81 or the ground surface 82. Four of the multiple CO2 sensors 20 are positioned at the four corners of the first virtual plane. In this embodiment, the first virtual plane is the ceiling surface 81. That is, the multiple CO2 sensors 20 are positioned on the ceiling surface 81.

[0109] For example, four CO2 sensors 20a to 20d are respectively located at the four corners of the ceiling surface 81. The remaining CO2 sensor 20e is located in the center of the ceiling surface 81. The CO2 sensor 20e is located in the same position as the human detection sensor 120.

[0110] Here, "same position" simply means a substantially identical range, and does not necessarily have to be exactly the same. For example, the CO2 sensor 20e and the human detection sensor 120 can be set to be a maximum distance of a few centimeters to tens of centimeters. Similarly, "angle" does not only refer to the situation where it coincides with the vertex of the rectangle in the top view of the ceiling surface 81, but also to any range that can be substantially considered to be the same as the vertex. For example, "angle" can also be set to a position a few centimeters to tens of centimeters away from the vertex of the rectangle.

[0111] A person detection sensor 120 detects the presence of people 90 within an indoor space 80. The person detection sensor 120 may be, for example, an infrared sensor or an image sensor. The person detection sensor 120 is positioned vertically above an area where the likelihood of a person 90 being present is high, such as a chair or work area.

[0112] The person detection sensor 120 outputs the detection result of person 90 to the control device 130. The detection result includes information indicating whether person 90 is present. The detection result may also include information indicating at least one of the location of the detected person 90 and the number of people.

[0113] The control device 130 controls the air conditioning unit 10 based on the CO2 concentration measured by each of the plurality of CO2 sensors 20. In this embodiment, the control device 130 also controls the air conditioning unit 10 based on the detection results obtained by the human detection sensor 120. Compared with the control device 30 according to Embodiment 1, the control device 130 includes a signal processing unit 132 instead of the signal processing unit 32.

[0114] The signal processing unit 132 estimates a first concentration distribution of carbon dioxide within a first virtual plane on which the multiple CO2 sensors 20 are located, based on the CO2 concentration measured by the multiple CO2 sensors 20. Since the five CO2 sensors 20a to 20e are located on the ceiling surface 81, the first concentration distribution is the CO2 concentration distribution within the ceiling surface 81. The first concentration distribution contains a CO2 concentration A(x, y) at each location determined by the x and y coordinates.

[0115] For example, the signal processing unit 132 generates a CO2 concentration distribution based on the CO2 concentration at each of the installation locations of the multiple CO2 sensors 20 using statistical methods. Specifically, as a statistical method, an algorithm for calculating contour lines is used. Examples of such algorithms include the maximum slope method, the Enhanced TIN (Enhanced Triangulated Irregular Network) method, the Kriging method, or the spline method. In this specification, the statistical method does not imply processing using physical simulation methods such as fluid dynamics simulations.

[0116] For example, such as Figure 4A As shown, based on the measured CO2 concentration values ​​of the six CO2 sensors 20a-20f installed on the ceiling surface 81, it is possible to generate data such as... Figure 4B The CO2 concentration distribution is shown. Furthermore, Figure 4A It is a perspective view showing the positions of people 90 and 92 and multiple CO2 sensors 20 located in the indoor space 80. Figure 4B It is shown Figure 4A The contour map shows the CO2 concentration distribution at the ceiling surface 81 (sensor mounting surface) of the indoor space 80. Figure 4B The x-axis and y-axis in the diagram are each in meters.

[0117] exist Figure 4A In the example shown, four CO2 sensors 20a–20d are positioned at the four corners of the ceiling surface 81. Two CO2 sensors 20e and 20f are positioned directly above people 90h and 92, respectively. This allows for high-precision detection of changes in CO2 concentration caused by the carbon dioxide exhaled by people 90 and 92, thus improving the accuracy of CO2 concentration distribution estimation.

[0118] The signal processing unit 132 estimates a second concentration distribution of carbon dioxide in one or more second virtual planes parallel to the first virtual plane based on the estimated first concentration distribution. Specifically, the signal processing unit 132 sets the CO2 concentration at position (x, y) included in the first concentration distribution as CO2 concentration A, and calculates the CO2 concentration B included in the second concentration distribution based on equation (1) shown in Embodiment 1. The calculated CO2 concentration B is the value at a position on a vertical line passing through position (x, y), which is a second position included in the second virtual plane. The signal processing unit 132 generates the second concentration distribution by calculating the CO2 concentration B for each coordinate (x, y). By continuously estimating the second concentration distribution along the height direction (z-axis direction) of the indoor space 80, the signal processing unit 132 can generate a three-dimensional CO2 concentration distribution of the entire indoor space 80. The three-dimensional CO2 concentration distribution (also referred to as "vertical distribution" in this embodiment) includes CO2 concentration B(x, y, z) at each position represented by coordinates (x, y, z).

[0119] In this embodiment, the signal processing unit 132 further estimates the first and second concentration distributions based on the position of the person 90 detected by the person detection sensor 120. Since the CO2 concentration increases vertically above the person 90, the accuracy of the first and second concentration distributions can be improved by utilizing the position of the person 90 for estimation. Specifically, by approximating the CO2 concentration distribution around the person 90 as a three-dimensional shape containing the person 90, such as a cylinder, an ellipsoid of revolution, or an upwardly opening trumpet shape, and superimposing it on the spatial distribution of CO2 concentration obtained above, high accuracy can be achieved. At this time, since the CO2 concentration of the person 90's exhaled breath is 4.5%, the CO2 concentration distribution inside the aforementioned three-dimensional shape can be estimated by considering only the breathing volume and the diffusion rate of carbon dioxide. Furthermore, by correcting this estimation using the CO2 concentration value near the person detection sensor 120, high accuracy can be achieved.

[0120] [action]

[0121] Next, use Figure 5 The operation of the air conditioning system 101 according to this embodiment will be explained. Figure 5 This is a flowchart illustrating the operation of the air conditioning system 101 according to this embodiment. Figure 5 This mainly shows the operation of the control device 130.

[0122] like Figure 5As shown, firstly, the control unit 33 acquires the air supply and exhaust function capability information of the air conditioning unit 10 (S10). Next, the signal processing unit 132 acquires position information indicating the positions of people 90 and 92 detected by the human detection sensor 120 via the first communication unit 31 (S20). Furthermore, the acquisition of position information (S20) can be performed either before the acquisition of capability information (S10) or after the acquisition of the CO2 concentration measurement value (S21).

[0123] Next, the signal processing unit 132 acquires the measured CO2 concentration from each of the plurality of CO2 sensors 20 via the first communication unit 31 (S21). The plurality of CO2 sensors 20 measure the CO2 concentration at each installation location, for example, based on an instruction from the control unit 33, and output information indicating the measured CO2 concentration to the control device 130. Alternatively, the plurality of CO2 sensors 20 may continuously or periodically measure the CO2 concentration and continuously or periodically output the measured CO2 concentration.

[0124] Next, the signal processing unit 132 calculates the horizontal distribution D(x, y) of the CO2 concentration (S22). Specifically, the signal processing unit 132 generates the CO2 concentration distribution in the ceiling surface 81 based on multiple measurements using statistical methods. For example, generating... Figure 4B The concentration distribution is shown.

[0125] Next, the signal processing unit 132 calculates the vertical distribution D(x, y, z) of the CO2 concentration by extending the horizontal distribution D(x, y) along the z-axis (S23). The vertical distribution D(x, y, z) is a three-dimensional distribution of the CO2 concentration within the indoor space 80. For each height above the ground 82, the signal processing unit 132 estimates the CO2 concentration distribution at each height using appropriate α and β based on the above equation (1). The estimated vertical distribution D(x, y, z) is temporarily stored, for example, in the storage unit 34.

[0126] The subsequent processing is the same as in Implementation Method 1. After the control device 130 controls the air conditioning unit 10 in a manner that prioritizes the air supply and exhaust function over the indoor temperature adjustment function, it repeats the processing from step S20. As a result, the CO2 concentration in the indoor space 80 can be rapidly reduced when it exceeds the threshold Dth, thereby maintaining the comfort of the indoor space 80.

[0127] Furthermore, in step S23, the signal processing unit 132 may also estimate only the CO2 concentration distribution at a predetermined height above the ground 82. For example, the signal processing unit 132 may estimate only the CO2 concentration distribution at the ground 82.

[0128] [Effects, etc.]

[0129] As described above, the air conditioning system 101 according to this embodiment includes a plurality of CO2 sensors 20. The plurality of CO2 sensors 20 are located in a first virtual plane parallel to the ceiling surface 81 or the ground surface 82. The signal processing unit 132 estimates a first concentration distribution of carbon dioxide in the first virtual plane based on a first concentration measured by each of the plurality of CO2 sensors 20, and estimates a second concentration distribution of carbon dioxide in one or more second virtual planes parallel to the first virtual plane and each containing one or more second locations based on the estimated first concentration distribution.

[0130] This allows for the generation of a three-dimensional CO2 concentration distribution within the indoor space 80, thus enabling the air conditioning equipment 10 to operate more efficiently.

[0131] Alternatively, for example, the plurality of CO2 sensors 20 may include more than four CO2 sensors 20. Four of the plurality of CO2 sensors 20 are disposed at the four corners of the indoor space 80 in a first virtual plane.

[0132] Therefore, by placing CO2 sensors 20 at the four corners where there are few people 90, the CO2 concentration measured by the four CO2 sensors 20 is less likely to be directly affected by the carbon dioxide contained in the breath of people 90. Thus, the estimation accuracy of CO2 concentration distribution in the virtual plane can be improved.

[0133] Additionally, for example, the air conditioning system 101 according to this embodiment also includes a person detection sensor 120 for detecting the presence of people in the indoor space 80. The signal processing unit 132 also estimates a first concentration distribution and a second concentration distribution based on the location of the person detected by the person detection sensor 120. Furthermore, for example, the plurality of CO2 sensors 20 includes a CO2 sensor disposed at the same location as the person detection sensor 120.

[0134] Therefore, the estimation of CO2 concentration distribution can reflect the impact of 90% of the carbon dioxide exhaled by humans, thus improving the accuracy of CO2 concentration distribution estimation.

[0135] [A variation of the configuration of multiple CO2 sensors]

[0136] Below, use Figures 6A to 6C A modified example of the configuration of multiple CO2 sensors 20 will be described below. Figures 6A to 6C These are perspective views showing the first to third examples of configurations of multiple CO2 sensors 20.

[0137] exist Figure 6AIn the example shown, four CO2 sensors 20a to 20d are positioned at the four corners of the floor 82. Alternatively, the four CO2 sensors 20a to 20d can also be positioned at a predetermined height between the ceiling surface 81 and the floor 82.

[0138] In addition, Figure 6B In the example shown, five CO2 sensors 20a-20e are positioned at the four corners and the center of the ceiling surface 81. Furthermore, CO2 sensor 20f is positioned on the floor 82. CO2 sensor 20f is positioned at one of the four corners of the floor 82, but it can also be positioned at the center of the floor 82, or at a predetermined position between the center and a corner.

[0139] In addition, Figure 6C In the example shown, four CO2 sensors 20a to 20d are located at the four corners of the floor 82. Furthermore, CO2 sensor 20e is located on the ceiling surface 81. CO2 sensor 20e is located at one of the four corners of the ceiling surface 81, but it can also be located at the center of the ceiling surface 81, or at a predetermined position between the center and a corner.

[0140] Alternatively, CO2 sensors 20 can be installed at the four corners of both the ceiling surface 81 and the floor 82. That is, a total of eight CO2 sensors 20 can be installed in the indoor space 80. Alternatively, a CO2 sensor 20 can be additionally installed at the center of at least one of the ceiling surface 81 and the floor 82. A total of ten CO2 sensors 20 can also be installed in the indoor space 80.

[0141] As shown above, Figures 6A to 6C Examples of configurations of multiple CO2 sensors 20 in a cuboid-shaped indoor space 80 are shown. However, the shape of the indoor space 80 may not be cuboid.

[0142] Figures 7A to 7F These are top views of the first to sixth examples, showing the shape of the indoor space and the configuration of the multiple CO2 sensors 20.

[0143] exist Figure 7A The example shown depicts an interior space 80a with a square top view. That is, both the ceiling surface 81 and the floor surface 82 have square top views and are of the same size. Furthermore, in Figure 7B The example shown depicts an interior space 80b with a rectangular top view. That is, both the ceiling surface 81 and the floor surface 82 are rectangular in shape and are of the same size. Figure 7A and Figure 7B In this case, four CO2 sensors 20a to 20d are arranged at the four corners, and one CO2 sensor 20e is arranged in the center.

[0144] exist Figure 7C and Figure 7D The example shown depicts an interior space 80c with a trapezoidal top view. That is, both the ceiling surface 81 and the floor surface 82 have trapezoidal top views and are of the same size.

[0145] exist Figure 7C In this configuration, four CO2 sensors 20a to 20d are positioned at the four corners, and one CO2 sensor 20e is positioned in the center. The center here is the intersection of the diagonals of the trapezoid. Furthermore, the CO2 sensor 20e can be located anywhere other than the four corners; for example, it could be located at the centroid of the trapezoid.

[0146] Alternatively, the trapezoidal interior space 80c can be divided into a quadrilateral area 80c1 and a triangular area 80c2. For example... Figure 7D As shown, five CO2 sensors 20a to 20e are arranged at the four corners and the center of the quadrilateral region 80c1. Additionally, CO2 sensors 20c, 20d, and 20f are arranged in the triangle of the triangular region 80c2. One CO2 sensor (specifically, CO2 sensor 20c or 20d) is located at a shared vertex in both the quadrilateral region 80c1 and the triangular region 80c2.

[0147] In addition, Figure 7E The example shown illustrates an interior space 80d whose top-view shape is represented by a combination of multiple quadrilaterals. The interior space 80d can be divided into a large quadrilateral region 80d1 and a smaller quadrilateral region 80d2. Five CO2 sensors 20a to 20e are arranged at the four corners and the center of quadrilateral region 80d1. Additionally, CO2 sensors 20d, 20f to 20h are arranged at the four corners of quadrilateral region 80d2. One CO2 sensor (specifically, CO2 sensor 20d) is arranged at a vertex shared by quadrilateral regions 80d1 and 80d2. Furthermore, a CO2 sensor 20 may also be arranged at the center of the smaller quadrilateral region 80d2.

[0148] In addition, Figure 7F The example shown depicts an interior space 80e with a circular top view. That is, both the ceiling surface 81 and the floor 82 are circular in top view and are of the same size. In this case, four CO2 sensors 20a-20d are arranged at equal intervals along the circumference. Additionally, CO2 sensor 20e is positioned at the center of the circle. Alternatively, the interior space 80e could also have an elliptical top view.

[0149] In this embodiment, an example is shown where CO2 sensors 20 are installed at each of the four corners of the ceiling surface 81. However, it is also possible to omit the CO2 sensor 20 at at least one of the four corners. The CO2 concentration at the location where the CO2 sensor 20 is not installed can be replaced by the average of the measurements from the other CO2 sensors 20. This is because the CO2 concentration in places like the four corners of the indoor space 80, where no one is present 90, is small due to the agitation of the airflow. In other words, the CO2 concentration at the four corners becomes approximately the same value.

[0150] (Implementation Method 3)

[0151] Next, implementation method 3 will be described.

[0152] In Embodiment 3, the main difference from Embodiments 1 and 2 is that an estimate of the CO2 concentration is performed at a time later than the time when the CO2 concentration is measured. The following explanation focuses on the differences from Embodiments 1 and 2, omitting or simplifying descriptions of commonalities.

[0153] [structure]

[0154] First, use Figure 8 The structure of the air conditioning system involved in Embodiment 3 will be described. Figure 8 This is a diagram showing the structure of the air conditioning system 201 according to this embodiment.

[0155] like Figure 8 As shown, the air conditioning system 201 includes an air conditioning unit 10, a CO2 sensor 20, a human detection sensor 120, a control device 230, and a cloud server 40.

[0156] The control device 230 estimates the CO2 concentration at a second time point, which is later than the first time point at which the CO2 concentration was measured. In this embodiment, compared with the control device 30 according to Embodiment 1, the control device 230 includes a signal processing unit 232 and a control unit 233 instead of the signal processing unit 32 and the control unit 33.

[0157] The signal processing unit 232 estimates the CO2 concentration at a second time point, which is later than the first time the CO2 concentration was measured, based on the CO2 concentration measured by the CO2 sensor 20 and the number of people detected by the human detection sensor 120. The second time point could be, for example, 10 minutes, 30 minutes, or 1 hour after the first time point. The second time point is a future time later than the time the CO2 concentration is estimated. In other words, the signal processing unit 232 predicts the CO2 concentration.

[0158] The signal processing unit 232 utilizes the following phenomenon: the CO2 concentration at a designated location increases proportionally to the number of people present in the indoor space 80 and the duration of their presence. The designated location is, for example, a corner of the floor 82 or a place with low foot traffic, such as that.

[0159] Figure 9 This is a graph showing the change in CO2 concentration over time. Figure 9 In the graph, the horizontal axis represents time (in minutes), and the vertical axis represents CO2 concentration (in ppm). Figure 9 This represents the measured value of the change in CO2 concentration in a closed space of a specified size, assuming the number of people remains constant. For example... Figure 9 As shown, the increase in CO2 concentration is roughly constant.

[0160] Therefore, the CO2 concentration at the second moment at the specified location can be easily represented by a linear function with time as the variable. The signal processing unit 232 estimates the CO2 concentration based on the following equations (2) and (3).

[0161] (2) A(t)=f(n)×(t-t0)+γ×A(t0)+η

[0162] (3) B(t)=α×A(t)+β

[0163] In equations (2) and (3), n represents the number of people detected by the human detection sensor 120. t0 is the first moment when the CO2 concentration is measured by the CO2 sensor 20. t is the second moment after the first moment, which is the predicted moment for the CO2 concentration.

[0164] A(t) is the CO2 concentration at position P0 where the CO2 sensor 20 is located at time t. A(t0) is the measured value of the CO2 concentration obtained by the CO2 sensor 20, equivalent to the so-called initial value. B(t) is the estimated value of the CO2 concentration at position P1, which is different from position P0, at time t. Figure 8 As shown, position P1 is, for example, contained at ground level 82. Position P1 is located on a vertical line passing through position P0. Alternatively, position P1 can be any position on the vertical line.

[0165] α, β, γ, and η are all coefficients. α and β, as in Implementation 1, are values ​​that may vary depending on the location where the estimation is performed. γ and η are values ​​determined based on the operating state of the air conditioning unit 10.

[0166] f(n) is a function of the number of people. The more people there are, the greater the increase in CO2 concentration; the fewer people there are, the smaller the increase in CO2 concentration. The function f(n) represents the relationship between the number of people and CO2 concentration. f(n) × (t-t0) represents the increase in CO2 concentration during the period from the measurement time t0 to the prediction time t (i.e., after time t-t0), based on the number of people n in the indoor space 80. For example, if we assume that the CO2 emissions from multiple people are the same, then f(n) = n × (CO2 concentration per person per unit time).

[0167] The control unit 233 controls the air conditioning unit 10 based on the CO2 concentrations A(t) and B(t) estimated by the signal processing unit 232. Specifically, when the CO2 concentrations A(t) and B(t) are greater than the threshold Dth, the control unit 233 controls the air conditioning unit 10 so that the CO2 concentration is lower than the threshold Dth at time t. That is, even if the CO2 concentration does not exceed the threshold Dth at the current time point (first time), the control unit 233 controls the air conditioning unit 10 as needed, prioritizing the air supply and exhaust functions over the indoor temperature adjustment functions.

[0168] [action]

[0169] Next, use Figure 10 The operation of the air conditioning system 201 according to this embodiment will be explained. Figure 10 This is a flowchart illustrating the operation of the air conditioning system 201 according to this embodiment. Figure 10 This mainly shows the operation of the control device 230.

[0170] like Figure 10 As shown, firstly, the control unit 233 acquires the air supply and exhaust function capability information of the air conditioning unit 10 (S10). Next, the signal processing unit 232 acquires the number of people information (S30) indicating the number of people n detected by the human detection sensor 120 via the first communication unit 31. Furthermore, the acquisition of the number of people information (S30) can be performed either before the acquisition of the capability information (S10) or after the acquisition of the CO2 concentration measurement value (S11).

[0171] Next, the signal processing unit 232 acquires the measured value of CO2 concentration from the CO2 sensor 20 via the first communication unit 31 (S11). The CO2 sensor 20, for example, measures the CO2 concentration at the set position P0 based on an instruction from the control unit 33, and outputs information indicating the measured CO2 concentration to the control device 230. The acquired measured value is A(t0) in equation (2).

[0172] Next, the signal processing unit 232 estimates the concentration A(t) at time t at the measurement position P0 obtained by the CO2 sensor 20 (S32). Specifically, the signal processing unit 232 calculates the CO2 concentration A(t) by substituting the number of people n and the CO2 concentration A(t0) into equation (2).

[0173] Next, the signal processing unit 232 estimates the CO2 concentration B(t) at time t at a position P1 that is different from the measurement position P0 (S33). Specifically, the signal processing unit 232 calculates the CO2 concentration B(t) by substituting the calculated A(t) into equation (3).

[0174] At this time, the signal processing unit 232 can also calculate the CO2 concentration at time t at each of a plurality of locations different from the measurement location P0. For example, the signal processing unit 232 can also calculate the vertical distribution of the predicted CO2 concentration along the vertical line VL. Similar to Embodiment 1, the vertical distribution of the predicted CO2 concentration can be calculated by applying Equation (1) for each height 82 above the ground.

[0175] Next, the signal processing unit 232 compares the CO2 concentration B(t) with the threshold Dth (S34). Furthermore, when multiple CO2 concentrations B(t) are calculated, the signal processing unit 232 extracts the maximum value Dmax(t) from the multiple CO2 concentrations B(t) and compares the extracted maximum value Dmax(t) with the threshold Dth.

[0176] When the CO2 concentration B(t) is below the threshold Dth ("Yes" in S34), the control unit 233 maintains the current control conditions of the air conditioning equipment 10 (S15). That is, since it is predicted that the CO2 concentration will not exceed the threshold Dth at a future time t, the CO2 concentration in the indoor space 80 is within the allowable range, and the control conditions do not need to be changed.

[0177] If the CO2 concentration B(t) exceeds the threshold Dth ("No" in S34), the control unit 233 determines the control conditions for keeping the CO2 concentration B(t) below the threshold Dth at time t based on the capability information (S36). For example, the control unit 233 calculates the required exhaust gas flow rate to keep the CO2 concentration B(t) below the threshold Dth and determines the control conditions for achieving the calculated exhaust gas flow rate. Furthermore, since the capability information is used to determine the control conditions, the acquisition of the capability information (S10) can also be performed after determining that the CO2 concentration B(t) exceeds the threshold Dth.

[0178] Next, the control unit 233 calculates the start time ts (S37) for operating the air conditioning unit 10 under the determined control conditions. The start time ts is a time that is later than the first time t0 and earlier than the second time t. That is, it is the time when the operation of the air conditioning unit 10, which prioritizes the air supply and exhaust functions, should begin in order to ensure that the CO2 concentration B(t) is below the threshold Dth at the second time t. Normally, even if the air supply and exhaust functions are prioritized, it takes a certain period of time for the CO2 concentration in the indoor space 80 to decrease. Therefore, by operating the air conditioning unit 10 with priority given to the air supply and exhaust functions starting from a time ts earlier than the second time t, it is possible to prevent the CO2 concentration B(t) from exceeding the threshold Dth at the second time t. For example, if the air supply and exhaust functions are operated at maximum output, it takes 30 minutes for the CO2 concentration B(t) to drop below the threshold Dth. In this case, the control unit 233 determines t-30 minutes as the time ts.

[0179] Next, at time ts, the control unit 233 controls the air conditioning unit 10 according to the control conditions determined in step S36 (S38). That is, after time ts, the control unit 233 controls the air conditioning unit 10 in a manner that prioritizes the air supply and exhaust function over the indoor temperature adjustment function.

[0180] Afterwards, at time t plus Δt (S39), the control device 230 repeats the process from step S30. Δt is, for example, 1 second, 10 seconds, 1 minute, or 10 minutes, but is not particularly limited.

[0181] Therefore, if it is predicted that the CO2 concentration B(t) in the indoor space 80 will exceed the threshold Dth, the air conditioning unit 10 can be activated to prevent the CO2 concentration from exceeding the threshold Dth. Thus, the period during which the CO2 concentration exceeds the threshold Dth can be avoided, thereby maintaining the comfort of the indoor space 80.

[0182] [Effects, etc.]

[0183] As described above, in the air conditioning system 201 of this embodiment, the signal processing unit 232 also estimates the second concentration at a second time later than the first time at which the first concentration was measured, based on the number of people present in the indoor space 80.

[0184] Therefore, the air conditioning unit 10 can be activated to prevent the CO2 concentration from exceeding the threshold Dth, thus maintaining the comfort of the indoor space 80. Furthermore, since there is sufficient leeway to prioritize air supply and exhaust functions, temperature or humidity changes caused by rapid ventilation can be suppressed. Therefore, the operation of the indoor temperature adjustment function, which maintains a constant temperature or humidity, can be suppressed, thereby reducing the increase in power consumption.

[0185] In addition, for example, if the number of people is set to n, the first time is set to t0, the second time is set to t, the second concentration is set to B(t), and the predicted value of the carbon dioxide concentration at the first position at the second time is set to A(t), the signal processing unit 232 estimates the second concentration based on the above equations (2) and (3).

[0186] Therefore, complex and computationally intensive calculations can be avoided, thus reducing the amount of computation required to efficiently control the air conditioning equipment 10.

[0187] Furthermore, similar to Embodiment 2, the air conditioning system 201 may also include multiple CO2 sensors 20, and the CO2 concentration distribution at a first moment in the mounting surface of the multiple CO2 sensors 20 may also be estimated. The CO2 concentration distribution at a second moment may also be estimated based on the estimated CO2 concentration distribution at the first moment.

[0188] (Implementation Method 4)

[0189] Next, implementation method 4 will be described.

[0190] In Embodiment 4, the main difference from Embodiments 1 to 3 is that it includes a presentation unit for displaying prescribed information. The following explanation will focus on the differences from Embodiments 1 to 3, omitting or simplifying descriptions of commonalities.

[0191] [structure]

[0192] First, use Figure 11 The structure of the air conditioning system involved in Embodiment 4 will be described. Figure 11 This is a diagram illustrating the structure of the air conditioning system 301 according to this embodiment. Figure 11 As shown, the air conditioning system 301, compared with the air conditioning system 1 according to Embodiment 1, also includes an information display unit 330.

[0193] Figure 12 This is a diagram illustrating the structure of the information presentation unit 330 according to this embodiment. Figure 12 As shown, the information display unit 330 includes a display monitor 331, a sound generating unit 333, and a light generating unit 335. The information display unit 330 displays information related to the CO2 concentration at a predetermined location indoors. Specifically, the information display unit 330 displays information related to the CO2 concentration (second concentration) estimated based on the measurement value obtained using the CO2 sensor 20.

[0194] Display monitor 331 is a display unit that displays images containing information related to CO2 concentration. Display monitor 331 is implemented, for example, using a liquid crystal display panel or an organic EL display panel. Display monitor 331 displays the average value and / or the monitored time variation of CO2 concentration at a specific moment. The CO2 concentration monitoring display is, for example, a display of the time variation of CO2 concentration at a location 1.2m above the ground. 1.2m is roughly equivalent to the torso of a standing person. For example, in... Figure 12 The display monitor 331 uses a graph with the horizontal axis representing time and the vertical axis representing CO2 concentration to display the change in CO2 concentration over time (monitoring results).

[0195] Additionally, when displaying average values, for example, multiple points such as 0.6m, 1.2m, and 1.8m above the ground can be averaged. This allows for an approximate estimate of the overall CO2 concentration exposed to a person. For example, in... Figure 12 The display monitor 331 displays text information indicating the average CO2 concentration at multiple locations.

[0196] Additionally, the display monitor 331 can also display a warning, as an example of information presentation, when certain conditions are met. These conditions could be, for example, a CO2 concentration deviating from a specified range. Furthermore, whether the specified conditions have been met is determined, for example, by the control unit 33 of the control device 30 or the control unit (not shown) of the information display unit 330.

[0197] The specified range for CO2 concentration is, for example, a lower limit of 300 ppm and an upper limit of 1000 ppm, but it is not limited to these limits. Generally, the CO2 concentration in outdoor air is around 400 ppm. Furthermore, the upper limit for CO2 concentration, considering comfort, is set at 1000 ppm. If the CO2 concentration is significantly lower than 400 ppm, it may indicate the introduction of a toxic gas different from the air. Therefore, management is carried out not only from a comfort perspective but also from a lower limit for CO2 concentration. This results in an air conditioning system 301 that is more useful from both comfort and safety perspectives.

[0198] When a warning is displayed, the display color indicating the CO2 concentration value is changed to red on the display monitor 331. Or, as... Figure 12 As shown, a bright spot 332 of a specified color (e.g., red) is displayed in the monitoring display as an anomaly.

[0199] The sound generating unit 333 and the light generating unit 335 are examples of warning units that issue warnings. The sound generating unit 333 and the light generating unit 335 issue warnings when predetermined conditions are met.

[0200] The sound generating unit 333 is a loudspeaker that emits prescribed sounds such as warning tones. The warning tones generated by the sound generating unit 333 are an example of sound presentation.

[0201] The light generating unit 335 is a light source that emits visible light, such as a red light that emits red light, like a warning light. The red light emitted by the light generating unit 335 is an example of utilizing the presentation of light.

[0202] Furthermore, the information presented by the information display unit 330 is not limited to the numerical value of CO2 concentration. For example, the information display unit 330 may also display the volume ratio (hereinafter referred to as the good space ratio) of the area where the CO2 concentration is within a predetermined range, i.e., the space with low and comfortable CO2 concentration within the indoor space 80. For example, in Figure 12 The display monitor 331 shows a good spatial ratio (unit: %). Therefore, compared with only displaying the average CO2 concentration, it is possible to understand the environmental conditions within the indoor space 80.

[0203] A favorable spatial proportion is estimated, for example, by the signal processing unit 32 of the control device 30. Specifically, the signal processing unit 32 calculates the volume of the area where the CO2 concentration is within a specified range based on an estimation of the three-dimensional distribution of CO2 concentration within the indoor space 80. The volume of the indoor space 80 is, for example, pre-stored in the storage unit 34. Thus, the signal processing unit 32 is able to calculate the favorable spatial proportion.

[0204] Additionally, the information display unit 330 may also issue a warning if the good space ratio is lower than a predetermined value. The warning is at least one of the following: the display monitor 331 changes the display color, the sound generator 333 generates a warning sound, and the light generator 335 generates a red light. The predetermined value is a lower limit of a pre-set allowable range, for example, stored in the storage unit 34.

[0205] Additionally, the information presentation unit 330 can also present an estimated time until the CO2 concentration deviates from a specified range. For example, in Figure 12 The display monitor 331 shows an estimated time until the CO2 concentration in the indoor space 80 deviates from the specified range as a predicted recommended ventilation time. This allows for the early prediction of environmental anomalies in the indoor space 80.

[0206] The prediction time is estimated, for example, by the signal processing unit 32 of the control device 30. Specifically, the signal processing unit 32 estimates the time until the upper limit of a predetermined range is reached based on the time change of CO2 concentration in the indoor space 80, and in the case of an increase in CO2 concentration, based on the instantaneous value of CO2 concentration at the estimated time point and the proportion of change.

[0207] [Effects, etc.]

[0208] As described above, the air conditioning system 301 according to this embodiment includes an information display unit 330 that displays information related to CO2 concentration.

[0209] This presents information related to the CO2 concentration within the indoor space 80, thus helping users or managers of the indoor space 80 to understand and respond to the environmental conditions within the space.

[0210] Alternatively, for example, the signal processing unit 32 can also estimate the volume ratio of the area of ​​the indoor space 80 where the CO2 concentration is within a specified range. The information presentation unit 330 can also display the estimated volume ratio.

[0211] This allows for the presentation of a proportion of areas with low CO2 concentrations (i.e., comfortable areas), thus enabling users or managers to be informed of the environmental conditions within the space in a more easily understandable way.

[0212] In addition, for example, when the volume ratio is lower than a specified value, the information display unit 330 may also perform at least one of screen display, sound display, and light display.

[0213] Therefore, warnings can be issued even when the proportion of comfortable areas is small.

[0214] Additionally, for example, the signal processing unit 32 can also estimate the estimated time until the CO2 concentration in the indoor space 80 deviates from a specified range. The information presentation unit 330 can also present the estimated time.

[0215] This allows for the display of an estimated time until comfort becomes compromised due to rising CO2 concentrations, thus enabling users or managers to be informed of the environmental conditions within the space in a more easily understandable manner.

[0216] In addition, for example, if the CO2 concentration deviates from the specified range, the information display unit 330 may also perform at least one of screen display, sound display, and light display.

[0217] This allows for warnings to be issued in situations that may compromise comfort or safety.

[0218] The information display unit 330 can also be configured to be separate from the control device 30 and capable of communicating with it via wired or wireless means. For example, the information display unit 330 can also be an information processing terminal such as a smartphone, tablet, or personal computer held by the person 90. Alternatively, the information display unit 330 can also be a single device integrated with the control device 30.

[0219] Alternatively, the information presentation unit 330 may not include the sound generating unit 333 and the light generating unit 335. Furthermore, the sound generating unit 333 may also output the information displayed on the display monitor 331 as sound. In other words, the sound generating unit 333 not only generates warnings but also has an information presentation function. In this case, the information presentation unit 330 may not even include the display monitor 331.

[0220] (other)

[0221] The air conditioning system and program involved in the present invention have been described above based on the above-described embodiments, but the present invention is not limited to the above-described embodiments.

[0222] For example, one embodiment of the present invention can also be a building equipped with the air conditioning systems 1, 101, or 201 described in the various embodiments above. Specifically, the building is a typical home, office building, school, hospital, or nursing facility with an interior space 80, but is not limited thereto. Alternatively, one embodiment of the present invention can also be a part of such a building (e.g., a room). Furthermore, one embodiment of the present invention can also be a mobile vehicle such as a tram, bus, or ship equipped with the aforementioned air conditioning system and interior space 80.

[0223] Furthermore, for example, in the embodiments described above, an example was shown where the maximum value Dmax among the measured CO2 concentration obtained using the CO2 sensor 20 and several estimated values ​​based on that measured value exceeds a threshold Dth, thus prioritizing the exhaust / gas supply function; however, this is not a limitation. For example, the signal processing units 32, 132, or 232 may also calculate the difference between the maximum value Dmax and the minimum value Dmin. The minimum value Dmin is the minimum value among the measured CO2 concentration obtained using the CO2 sensor 20 and several estimated values ​​based on that measured value.

[0224] As described above, the CO2 concentration increases in the region from near the mouth of person 90 to vertically above person 90, and tends to decrease further away from person 90. However, if ventilation of the indoor space 80 is not performed and the amount of carbon dioxide emitted from person 90 increases, carbon dioxide accumulates in the indoor space 80, and the CO2 concentration becomes uniform overall. Therefore, the difference between the maximum value Dmax and the minimum value Dmin becomes less than a predetermined threshold. Consequently, the control unit 33 can also control the air conditioning unit 10 in a manner that prioritizes the air supply and exhaust function over the indoor temperature adjustment function when the calculated difference is less than the predetermined threshold. Thus, the comfort of the indoor space 80 can be maintained.

[0225] Alternatively, the control unit 33 can also control the air conditioning unit 10 in a manner that prioritizes the air supply and exhaust function over the indoor temperature adjustment function if the estimated CO2 concentration at the ground 82 exceeds a predetermined threshold. If the CO2 concentration near the ground 82 in locations far from people 90, such as the four corners of the ground 82 in the indoor space 80, is higher than the predetermined threshold, it can be determined that the indoor space 80 contains a large amount of carbon dioxide as a whole, and ventilation should be carried out.

[0226] Furthermore, while examples of CO2 sensor 20 being installed on a ceiling or floor have been described in various embodiments, this is not a limitation. For example, CO2 sensor 20 could also be a portable, handheld CO2 sensor. For instance, a handheld CO2 sensor 20 could be placed on a table or similar surface by a person 90 to measure CO2 concentration. In this case, the formula for estimating CO2 concentration would differ from the above. For example, signal processing units 32, 132, or 232 might use a linear formula to estimate the distribution in the height direction, based on the height of the CO2 sensor placed on the table above the ground and the CO2 concentration at the location where it is placed.

[0227] Additionally, for example, it can issue an alarm when the CO2 concentration deviates from the permissible range, thus enabling remote on-site diagnostics. Furthermore, in cases of abnormal CO2 concentrations, it can also be used to assist maintenance personnel such as facility managers in diagnosing sensor faults and / or liaising for repairs.

[0228] Furthermore, there are no particular limitations regarding the communication method between devices described in the above embodiments. When wireless communication is performed between devices, the wireless communication method (communication standard) may be, for example, short-range wireless communication such as ZigBee (registered trademark), Bluetooth (registered trademark), or wireless LAN (Local Area Network). Alternatively, the wireless communication method (communication standard) may also be communication via a wide area communication network such as the Internet. Additionally, wired communication may be used instead of wireless communication between devices. Specifically, wired communication may use power line communication (PLC) or wired LAN communication, etc.

[0229] Furthermore, in the above embodiments, the processing performed by a specific processing unit may also be performed by other processing units. Additionally, the order of multiple processing steps may be changed, or multiple processing steps may be performed in parallel. Furthermore, the distribution of structural elements of air conditioning systems 1, 101, or 201 to multiple devices is an example. For example, structural elements of one device may also be possessed by other devices.

[0230] For example, the processing described in the above embodiments can be implemented either centrally using a single device (system) or distributedly using multiple devices. Furthermore, the number of processors executing the above program can be singular or plural. That is, it can be either centralized or distributed processing.

[0231] Furthermore, in the above embodiments, all or part of the structural elements such as the control unit can be constructed by dedicated hardware, or they can be implemented by executing software programs suitable for each structural element. Each structural element can also be implemented by a program execution unit such as a CPU (Central Processing Unit) or processor reading and executing software programs recorded in recording media such as HDD (Hard Disk Drive) or semiconductor memory.

[0232] In addition, structural elements such as the control unit can also be composed of one or more circuits. These one or more circuits can be either general-purpose or special-purpose circuits.

[0233] One or more circuits may include, for example, semiconductor devices, integrated circuits (ICs), or large-scale integrated circuits (LSIs). ICs or LSIs can be integrated onto a single chip or multiple chips. They are referred to here as ICs or LSIs, but the terminology varies depending on the degree of integration; they may also be called system LSIs, very large-scale integrated circuits (VLSIs), or ultra-large-scale integrated circuits (ULSIs). Additionally, field-programmable gate arrays (FPGAs), programmed after the LSI is manufactured, can also be used for the same purpose.

[0234] Furthermore, the general or specific embodiments of the present invention can also be implemented by a system, apparatus, method, integrated circuit, or computer program. Alternatively, it can be implemented by a computer-readable, non-transitory recording medium such as an optical disc, HDD, or semiconductor memory storing the computer program. Additionally, it can be implemented by any combination of systems, apparatus, methods, integrated circuits, computer programs, and recording media.

[0235] In addition, this invention also includes various modifications to the embodiments that can be conceived by those skilled in the art, or embodiments that are achieved by arbitrarily combining the structural elements and functions of the embodiments without departing from the spirit of the invention.

[0236] Explanation of reference numerals in the attached figures

[0237] 1, 101, 201, 301: Air conditioning system; 10: Air conditioning equipment; 11: Gas supply equipment; 12: Exhaust equipment; 20, 20a, 20b, 20c, 20d, 20e, 20f, 20g, 20h: CO2 sensors; 32, 132, 232: Signal processing unit; 33, 233: Control unit; 80, 80a, 80b, 80c, 80d, 80e: Indoor space; 81: Ceiling surface; 82: Floor; 90, 92: People; 120: Person detection sensor; 330: Information presentation unit.

Claims

1. An air conditioning system, comprising: Air conditioning equipment has functions of air supply and exhaust and indoor temperature adjustment, and is used to regulate the air in an indoor space; A CO2 sensor is installed at a first location within the indoor space to measure a first concentration of carbon dioxide at the first location. A signal processing unit estimates a second concentration of carbon dioxide at each of more than one second location based on a first concentration measured by the CO2 sensor, wherein the height of the second location from the floor or ceiling of the indoor space differs from the height of the first location from the floor or ceiling, and the second location lies on a vertical line passing through the first location; and The control unit compares the maximum concentration among the first concentration and one or more second concentrations with a threshold, and if the maximum concentration exceeds the threshold, changes the control conditions of the air conditioning equipment. Specifically, when the first concentration is set to A and the second concentration is set to B, The signal processing unit estimates the second concentration based on the formula: B = α × A + β, where α and β are coefficients. The air conditioning system is equipped with multiple CO2 sensors. Multiple CO2 sensors are located in a first virtual plane parallel to the ceiling surface or the floor. The signal processing unit estimates the first concentration distribution of carbon dioxide within the first virtual plane based on the first concentration measured by each of the plurality of CO2 sensors. The signal processing unit estimates a second concentration distribution of carbon dioxide within one or more second virtual planes that are parallel to the first virtual plane and each contain one or more of the second locations, based on the estimated first concentration distribution.

2. The air conditioning system according to claim 1, wherein, The first location is located on the ceiling surface or the floor.

3. The air conditioning system according to claim 1 or 2, wherein, The first position is located on the ceiling surface. The more than one second position refers to a plurality of distinct second positions on a vertical line passing through the first position.

4. The air conditioning system according to claim 1 or 2, wherein, The plurality of CO2 sensors includes more than five CO2 sensors. Five of the multiple CO2 sensors are located at the four corners of the indoor space in the first virtual plane, and at the intersection of the diagonals of the quadrilaterals with the four corners as vertices.

5. The air conditioning system according to claim 1 or 2, wherein, It also has a human detection sensor to detect the presence of people in the indoor space. The signal processing unit also estimates the first concentration distribution and the second concentration distribution based on the location of the person detected by the person detection sensor.

6. The air conditioning system according to claim 5, wherein, The plurality of CO2 sensors include a CO2 sensor located at the same position as the human detection sensor.

7. The air conditioning system according to claim 1 or 2, wherein, The signal processing unit also estimates the second concentration at a second time later than the first time when the first concentration was measured, based on the number of people present in the indoor space.

8. The air conditioning system according to claim 7, wherein, Given the number of people as n, the first time as t0, the second time as t, the second concentration as B(t), and the predicted concentration of carbon dioxide at the first position at the second time as A(t),... The signal processing unit estimates the second concentration based on the following two formulas. A(t)=f(n)×(t-t0)+γ×A(t0)+η B(t)=α×A(t)+β Where α, β, γ, and η are coefficients, and f(n) is a function with n as the variable.

9. The air conditioning system according to claim 1 or 2, wherein, If at least one of the first concentration and one or more of the second concentrations exceeds a predetermined threshold, the control unit controls the air conditioning equipment in such a manner that the air supply and exhaust function takes precedence over the indoor temperature adjustment function.

10. The air conditioning system according to claim 1 or 2, wherein, It also has a presentation unit that displays information related to the second concentration.

11. The air conditioning system according to claim 10, wherein, The signal processing unit estimates the volume proportion of the indoor space where the second concentration is within a specified range. The presentation section presents the volume ratio.

12. The air conditioning system according to claim 11, wherein, When the volume ratio is lower than a predetermined value, the presentation unit performs at least one of image display, sound presentation, and light presentation.

13. The air conditioning system according to claim 10, wherein, The signal processing unit estimates the estimated time until the second concentration in the indoor space deviates from the specified range. The presentation unit displays the estimated time.

14. The air conditioning system according to claim 10, wherein, If the second concentration deviates from the specified range, the presentation unit performs at least one of image display, sound presentation, and light presentation.

15. A building comprising an air conditioning system according to any one of claims 1 to 14.

16. A program recording medium that enables a computer to execute a control method for controlling an air conditioning unit, the air conditioning unit having air supply and exhaust functions and indoor temperature adjustment functions, for regulating the air in an indoor space. In the control method, The first concentration of carbon dioxide at the first location is obtained from a CO2 sensor installed at the first location in the indoor space. Based on the first concentration, the second concentration of carbon dioxide at each of the more than one second location is estimated, wherein... The second position is at a different height from the floor or ceiling of the indoor space than the first position is at a different height from the floor or ceiling, and the second position is located on a vertical line passing through the first position. The maximum concentration among the first concentration and one or more second concentrations is compared with a threshold. If the maximum concentration exceeds the threshold, the control conditions of the air conditioning equipment are changed. Specifically, when the first concentration is set to A and the second concentration is set to B, In estimating the second concentration, the second concentration is estimated based on the formula: B = α × A + β, where α and β are coefficients. Multiple CO2 sensors are provided. Multiple CO2 sensors are located in a first virtual plane parallel to the ceiling surface or the floor. In the control method, The first concentration distribution of carbon dioxide within the first virtual plane is estimated based on the first concentration measured by each of the plurality of CO2 sensors. Based on the estimated first concentration distribution, a second concentration distribution of carbon dioxide is estimated within one or more second virtual planes that are parallel to the first virtual plane and respectively contain one or more second locations.

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