Gas concentration estimation system, gas concentration estimation method, and control device

Abstract

To estimate a gas concentration without providing a gas concentration sensor.SOLUTION: The present disclosure relates to a gas concentration estimation system that estimates a concentration of predetermined gas in a space ventilated by an environmental device, and has a control unit that calculates an amount of change in gas concentration per unit time using the number of people present in the space. The control unit accumulates the amount of change with the gas concentration in the space before the update, to update the gas concentration, and uses a gas concentration of outside air as an initial value of the gas concentration before the update.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present disclosure relates to a gas concentration estimation system, a gas concentration estimation method, and a control device. [Background technology]

[0002] Environmental equipment such as air conditioners and ventilation equipment that can ventilate are known. Ventilation can bring the gas concentration in a space closer to that of the outside air. For example, it is possible to lower the CO2 concentration in a space to the same level as that of the outside air. On the other hand, when environmental equipment ventilates, an outside air load is generated, consuming more electricity than when not ventilating.

[0003] A technique for estimating an appropriate ventilation volume based on CO2 concentration is known (see, for example, Patent Document 1). Patent Document 1 discloses a technique for estimating ventilation volume by substituting CO2 concentrations at two different times into a relational equation. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Patent No. 5394668 Summary of the Invention [Problem to be solved by the invention]

[0005] However, conventional techniques require a gas concentration sensor to detect the concentration of gases such as CO2 in order to estimate the gas concentration.

[0006] The present disclosure provides a technique that can estimate a gas concentration without a gas concentration sensor. [Means for solving the problem]

[0007] A first aspect of the present disclosure is A gas concentration estimation system that estimates the concentration of a predetermined gas in a space ventilated by an environmental device, a control unit that calculates a change in gas concentration per unit time using the number of people in the space; the control unit updates the gas concentration by accumulating the amount of change to the gas concentration in the space before updating; The gas concentration of the outside air is used as the initial value of the gas concentration before updating.

[0008] According to the first aspect of the present disclosure, the gas concentration can be estimated without a gas concentration sensor.

[0009] A gas concentration estimation system according to a second aspect of the present disclosure is the gas concentration estimation system according to the first aspect, The control unit outputs the updated gas concentration.

[0010] A gas concentration estimation system according to a third aspect of the present disclosure is the gas concentration estimation system according to the first or second aspect, the control unit accepts an input of the gas concentration in the space; If there is a difference between the updated gas concentration and the input gas concentration that is equal to or greater than a threshold value, the parameters of a model formula that calculates the change in gas concentration per unit time using the number of people in the space are corrected.

[0011] A gas concentration estimation system according to a fourth aspect of the present disclosure is the gas concentration estimation system according to the third aspect, The parameters of the model formula are the air volume of the draft, the number of breaths per unit time, and the expiratory volume, When the input gas concentration is greater than the updated gas concentration, the control unit performs at least one of reducing the air volume of the gap, increasing the number of breaths per unit time, or increasing the exhaled air volume; If the input gas concentration is smaller than the updated gas concentration, at least one of the following is performed: increasing the air volume of the gap, reducing the number of breaths per unit time, or reducing the exhaled air volume.

[0012] A gas concentration estimation system according to a fifth aspect of the present disclosure is the gas concentration estimation system according to any one of the first to fourth aspects, The control unit obtains the number of people present in the space by detecting people entering and exiting the space photographed by a camera, by detecting people captured in an image of the space, by detecting people detected by a motion sensor installed in the seat, by detecting people using the space obtained from a scheduling system, or by manually inputting the number of people present.

[0013] A gas concentration estimation system according to a sixth aspect of the present disclosure is the gas concentration estimation system according to any one of the first to fifth aspects, The control unit continues updating the gas concentration for each unit time for 24 hours.

[0014] A gas concentration estimation system according to a seventh aspect of the present disclosure is the gas concentration estimation system according to any one of the first to sixth aspects, The control unit calculates the gas concentration using the current ventilation volume of the environmental device and the number of people in the space, and determines the next ventilation volume based on the gas concentration. Furthermore, the gas concentration is calculated using the next ventilation rate and the number of people in the space, and the ventilation rate for the next time is determined based on the gas concentration.

[0015] A gas concentration estimation system according to an eighth aspect of the present disclosure is the gas concentration estimation system according to any one of the first to seventh aspects, When calculating the gas concentration, the control unit uses an estimated value of the ventilation volume other than that ventilated by the environmental device.

[0016] A gas concentration estimation system according to a ninth aspect of the present disclosure is the gas concentration estimation system according to the eighth aspect, The estimated ventilation volume is the draft volume.

[0017] A gas concentration estimation system according to a tenth aspect of the present disclosure is the gas concentration estimation system according to any one of the first to ninth aspects, the control unit calculates a first airflow rate of the environmental device for a predetermined period of time assuming that the environmental device will continue to operate at a predetermined ventilation rate; calculating the gas concentration based on a predetermined occupancy model, and calculating a second airflow rate of the environmental device for a predetermined period when a ventilation rate is adjusted according to the calculated gas concentration; calculating a first power consumption consumed at the first airflow rate and a second power consumption consumed at the second airflow rate; The difference between the first air volume and the second air volume, or the difference between the first power consumption and the second power consumption is displayed.

[0018] A gas concentration estimation system according to an eleventh aspect of the present disclosure is the gas concentration estimation system according to the tenth aspect, The control unit calculates an outside air load from each of the first air volume and the second air volume, and calculates the first power consumption and the second power consumption using the outside air load.

[0019] A gas concentration estimation system according to a twelfth aspect of the present disclosure is the gas concentration estimation system according to the first aspect, the predetermined gas is CO2, The control unit calculates the increase A in CO2 volume due to breathing as follows: A = (CO2 concentration in exhaled air - CO2 concentration in the space) x exhaled air volume x number of breaths per unit time x number of people in the room. The amount of CO2 volume reduction B due to ventilation and drafts is B = (CO2 concentration in the room - CO2 concentration in the outside air) x ventilation air volume + (CO2 concentration in the room - CO2 concentration in the outside air) x draft volume Calculate by The change in volume of CO2 per unit time in the space, ΔPr, is ΔPr=AB Calculate by The CO2 concentration Pr after the unit time has elapsed is Pr←Pr+(ΔPr / space volume)× the above unit time It is calculated by:

[0020] A thirteenth aspect of the present disclosure is A gas concentration estimation method performed by a gas concentration estimation system that estimates the concentration of a predetermined gas in a space ventilated by an environmental device, comprising: the control unit calculates the amount of change in gas concentration per unit time using the number of people in the space; updating the gas concentration by accumulating the change amount to the gas concentration in the space before updating; The gas concentration of the outside air is used as the initial value of the gas concentration before updating.

[0021] According to the thirteenth aspect of the present disclosure, the gas concentration can be estimated without a gas concentration sensor.

[0022] A fourteenth aspect of the present disclosure is A control device that estimates the concentration of a predetermined gas in a space ventilated by an environmental device, Calculating the change in gas concentration per unit time using the number of people in the space; updating the gas concentration by accumulating the change amount to the gas concentration in the space before updating; The gas concentration of the outside air is used as the initial value of the gas concentration before updating.

[0023] According to the fourteenth aspect of the present disclosure, the gas concentration can be estimated without a gas concentration sensor. [Effects of the Invention]

[0024] According to the present disclosure, the gas concentration can be estimated without a gas concentration sensor. [Brief explanation of the drawings]

[0025] [Figure 1] FIG. 1 is a diagram for explaining an outline of a method for estimating CO2 concentration. [Figure 2] 1 is an example of a schematic perspective view of a main part of a gas concentration estimation system. [Figure 3] FIG. 10 is a diagram showing another example of a schematic perspective view of the main part of the gas concentration estimation system. [Figure 4]1 is an example of a system configuration diagram of a gas concentration estimation system. [Figure 5] FIG. 1 is a diagram illustrating an example of a hardware configuration of an information processing device. [Figure 6] FIG. 2 is an example of a functional block diagram illustrating functions of an information processing apparatus, divided into blocks. [Figure 7] FIG. 3 is a diagram illustrating parameters stored in a parameter storage unit. [Figure 8] 1 is an example of a formula for calculating the amount of change ΔPr in the volume of CO2 in a space per unit time, and a formula for estimating the CO2 concentration in a space. [Figure 9] 10 is a flowchart illustrating an example of a process in which an information processing device estimates a CO2 concentration Pr and controls an environmental device based on the estimated CO2 concentration Pr. FIG. [Figure 10] FIG. 2 is an external view of an example of a remote control device. [Figure 11] FIG. 10 is a diagram showing an example of a graph of various indices when constant air volume ventilation control and ventilation control are performed using a CO2 concentration Pr. [Figure 12] 10 is an example of a flowchart illustrating a process in which a number of people estimation unit estimates the number of people in a space when a manager inputs a CO2 concentration measured by a CO2 sensor into an information processing device. FIG. [Figure 13] FIG. 10 is a flowchart illustrating an example of a process performed by a parameter correction unit to correct parameters. [Figure 14] FIG. 2 is an example of a functional block diagram illustrating functions of an information processing apparatus, divided into blocks. [Figure 15] FIG. 10 is a diagram illustrating an example of a number-of-occupants model. [Figure 16] 10 is a flowchart illustrating an example of a process in which the information processing device presents the difference between the first air volume and the second air volume, and the difference between the first power consumption and the second power consumption. FIG. [Figure 17] 10A and 10B are diagrams illustrating examples of display of the difference between the first air volume and the second air volume, the difference between the first power consumption and the second power consumption, and the difference between the first electricity rate and the second electricity rate presented by the presentation unit. DETAILED DESCRIPTION OF THE INVENTION

[0026] A gas concentration estimation system and a gas concentration estimation method performed by the gas concentration estimation system will be described below as an example of an embodiment of the present invention.

[0027] <Ventilation and outdoor air load> It is known that ventilation is effective in improving and maintaining air quality, such as CO2 concentration, in spaces where people are present. For this reason, customers who purchase environmental equipment have assumed the number of people in the space, selected the equipment accordingly, and adjusted the ventilation volume by turning the equipment on and off. In other words, there is no control in place to fine-tune the ventilation volume to match the actual number of people in the room.

[0028] On the other hand, the actual number of people in a room is often less than the expected number of people (because underestimating the maximum number of people in a room can easily result in high CO2 concentrations even when ventilation is performed). For this reason, customers ventilate with a ventilation volume greater than necessary for the actual number of people present. When ventilating, outside air flows into the space, but because the temperature and humidity of the outside air differ from those inside the space, an outside air load is generated to control the temperature and humidity of the outside air that flows into the space through ventilation. This outside air load varies depending on the ventilation volume, the temperature and humidity of the outside air, but is said to account for one-third of the power consumption of environmental equipment. Therefore, adjusting the ventilation volume to match the actual number of people present can reduce the outside air load caused by ventilation and enable power consumption to be reduced.

[0029] Because the actual number of people in a room correlates with air quality, such as CO2 concentration, determining an appropriate ventilation rate requires either the number of people in the room or the CO2 concentration. However, some environmental devices are not equipped with CO2 sensors. Furthermore, although obtaining an accurate number of people is costly, it is possible to roughly estimate the number of people in the room. Therefore, this embodiment describes a method for estimating CO2 concentration based on the approximate number of people in the room without using a CO2 sensor.

[0030] [First embodiment] <Outline of environmental equipment operation> A method for estimating CO2 concentration according to this embodiment will be described with reference to FIG. 1. FIG. 1 is a diagram illustrating an outline of a method for estimating CO2 concentration according to this disclosure. Air is composed of nitrogen (approximately 78%), oxygen (approximately 21%), argon (approximately 0.93%), CO2 (approximately 0.03%), and other gases (approximately 0.04%). Meanwhile, the breath exhaled by a person is composed of nitrogen (approximately 78%), oxygen (15-16%), CO2 (4-5%), other gases, and trace gases generated within the body (approximately 1% including other gases). Therefore, CO2 and other trace gases increase with breathing. These gases are not contained in the original air, so they can be said to increase with breathing. Among gases, the change in CO2 concentration is extremely large, at 4-5%. In this embodiment, CO2 is used as an example of a gas whose concentration changes with exhalation. An environmental device that suppresses increases in CO2 concentration by controlling the ventilation volume according to the CO2 concentration will be described. One of the features of this device is that a CO2 sensor is not required for CO2 concentration estimation.

[0031] First, the CO2 concentration in the space increases due to the increase in CO2 due to exhalation. When N people in the space each breathe for a unit time (for example, 10 minutes), the increase in the volume of CO2, A, is calculated as follows: A = (CO2 concentration in exhaled air - CO2 concentration in air) x exhaled volume x number of breaths per unit time x N people ……(1) On the other hand, environmental equipment exhausts air from within a space to the outside and draws outside air into the space. Also, drafts flow into the space when doors are opened or closed, or through gaps. Therefore, the reduction in the volume of CO2 in a space due to ventilation or drafts per unit time, B, can be calculated as follows: B = (CO2 concentration in the room - CO2 concentration in the outside air) x ventilation air volume + (CO2 concentration in the room - CO2 concentration in the outside air) x draft volume ……(2) Therefore, the change in volume of CO2 per unit time in the space, ΔPr, is calculated as follows: ΔPr=AB ……(3) From the above, the CO2 concentration Pr after t seconds is calculated using equation (4). Pr (an example of the second gas concentration) on the left side is the updated value, and Pr (an example of the first gas concentration) on the right side is the value before the update. Note that "ΔPr / space volume" represents the conversion of the change in volume ΔPr into CO2 concentration. Pr←Pr+(ΔPr / space volume)×t ……(4) In this way, the environmental device of this embodiment can predict the CO2 concentration in a space without using a CO2 sensor. As shown in equation (4), the environmental device can estimate the CO2 concentration in the future by accumulating the amount of change in CO2 concentration over a unit time with the current CO2 concentration. Furthermore, since the CO2 concentration in t seconds can be predicted, feedforward control becomes possible, which may be more advantageous than feedback control using a CO2 sensor. For example, it is possible to suppress the increase in CO2 concentration before it exceeds a certain level.

[0032] Furthermore, if a CO2 sensor is available to the manager (if the CO2 concentration in the space can be measured) even though it is not connected to the information processing device 60, the manager can input the value detected by the CO2 sensor into the information processing device 60, which can then reverse-calculate the number of people present in the room. Furthermore, the information processing device 60 can correct the parameters (air volume of draft, exhaled air volume, and number of breaths per unit time) in equations (1) and (2) by comparing the detected value of CO2 concentration with the estimated value.

[0033] <Terminology> The space is a space that has enough air for humans to survive, such as an indoor space. Specific spaces vary, but they can be anything, such as an office, factory, conference room, seminar room, living room, movie theater, exhibition room, etc.

[0034] Gas refers to the composition of air (gases that make up air). Gas may include not only the original components of air such as oxygen, carbon dioxide, and nitrogen, but also substances contained in human exhaled breath. Gas concentration is the concentration of gas in a space (the ratio of the volume of gas to the volume of space). In this embodiment, CO2 will be used as an example of gas.

[0035] The unit time does not have to be a single unit of time such as one second, one minute, or one hour, but can be any time that can be specified or managed. Also, the unit time does not have to be constant at all times, and can be variable depending on the day of the week, time of day, etc.

[0036] A manager is someone who has already installed a gas concentration estimation system and is responsible for daily operation, regular inspections, and repairs to ensure that the system maintains its functionality. The manager may be the seller or user of the gas concentration estimation system. A person present in the space is someone who is present in the space. A seller is a person in charge of the manufacturer or sales company that provides the gas concentration estimation system. A customer is someone who does not have a gas concentration estimation system but is considering installing one.

[0037] Outside air refers to the part of the atmosphere surrounding the Earth that is near the ground. Outside air may contain pollutants such as pollen, dust, and PM2.5. Outside air gas concentrations are the concentrations of gases in this outside air.

[0038] <System configuration example> 2 is a schematic perspective view of an example of the main components of a gas concentration estimation system 100. In the gas concentration estimation system 100, an environmental device 10, a user terminal 70, and an information processing device 60 are communicably connected via a network N. While a sensor unit 8 is shown in FIG. 2, it is assumed that the sensor unit 8 is not connected to the network N, but is carried by an administrator or placed in the space 7.

[0039] When a manager can use the sensor unit 8 to measure the CO2 concentration in the space 7, the sensor unit 8 is installed in the space 7 where there are occupants 9. Two or more sensor units 8 may be installed in the space. The sensor unit 8 preferably has an air intake mechanism and has a gas concentration sensor built into the air flow path. In this embodiment, CO2 is used as an example of a gas, so the sensor may be a CO2 sensor. There are no particular limitations on the CO2 detection method of the CO2 sensor, but the NDIR method (Non-Dispersive Infrared absorption) is known, for example.

[0040] The environmental device 10 may be an air conditioner or a ventilation device, but may be any device having a ventilation function. The environmental device 10 may have functions other than the ventilation function, for example, multiple functions such as a temperature control function or an air purifier. The environmental device 10 may only exhaust air and take in outside air by using the negative pressure generated in the space 7, or may both exhaust and intake air, or may only intake air. Furthermore, the ventilated air may or may not pass through a total heat exchanger. Multiple environmental devices 10 may be placed in one space 7.

[0041] The user terminal 70 is a terminal device used by an administrator of the gas concentration estimation system 100. A web browser or a native application is executed on the user terminal 70, and the user terminal 70 receives information to be displayed on the display from the information processing device 60 via the network N. The administrator can display the current CO2 concentration or the future CO2 concentration and operate the environmental device 10 so as to reduce or prevent the CO2 concentration from increasing. The user terminal 70 may be portable by the administrator. Furthermore, the user terminal 70 does not need to be installed in the same space 7 as the space 7 in which the sensor unit 8 is installed. Furthermore, the user terminal 70 may be used or viewed by general users (in the present disclosure, the room occupants 9, sellers, customers, etc.).

[0042] If the environmental device 10 is in a building managed by a company, the manager may be, for example, a facility manager, and if the environmental device 10 is in a private home, the manager may be a resident or their family. A general user is a person who uses the space 7, such as a room occupant 9.

[0043] In the present disclosure, the information processing device 60 is a server device that performs various information processing. The information processing device 60 estimates the CO2 concentration by substituting several parameters into a calculation formula. The information processing device 60 transmits the CO2 concentration to a remote control device or a user terminal 70 (described later), and controls the environmental device 10 so as not to decrease or increase the CO2 concentration.

[0044] 2, a remote control device, which will be described later, may be connected to the network N and the environmental device 10. Furthermore, the sensor unit 8 may be built into the remote control device.

[0045] The information processing device 60 estimates the CO2 concentration based on the number of people in the room without using a CO2 sensor. If the manager can measure the CO2 concentration in the space 7, the information processing device 60 estimates the number of people in the room based on the detected CO2 concentration. If a CO2 sensor is available, the information processing device 60 corrects parameters for estimating the CO2 concentration based on the difference between the estimated CO2 concentration and the CO2 concentration detected by the CO2 sensor.

[0046] <<System configuration variations>> FIG. 3 shows another example of a schematic perspective view of the main components of the gas concentration estimation system 100. The gas concentration estimation system 100 mainly includes one outdoor unit 13a as a heat source unit, one or more indoor units 13b as utilization units, and a remote control device (hereinafter referred to as "remote control device 15") as an input device for inputting commands related to various settings. The remote control device 15 is a user interface that accepts settings such as temperature and humidity. The functions of the information processing device 60 may be the same as those in FIG. 2.

[0047] The outdoor unit 13a and the indoor unit 13b are referred to as air conditioners (an example of environmental equipment 10). The outdoor unit 13a and the indoor unit 13b are connected by a refrigerant communication pipe (gas communication pipe GP) to form a refrigerant circuit. In addition, the gas concentration estimation system 100 has multiple communication networks (network NW1, network NW2) that function as transmission paths for signals between the indoor unit and the outdoor unit. The network NW2 may be wired or wireless.

[0048] According to the configuration of FIG. 3, the indoor unit 13b has a built-in gas concentration sensor installed in the air intake or the like. In this embodiment, CO2 is used as an example of a gas, so the sensor may be a CO2 sensor 11. The CO2 sensor 11 is not connected to the network NW1. The CO2 concentration detected by the CO2 sensor 11 is transmitted to the remote control device 15. Therefore, as in FIG. 2, the administrator can know the CO2 concentration in the space 7 displayed on the remote control device 15. In FIG. 3 as well, instead of disposing the CO2 sensor 11 in the air intake, an independent sensor unit 8 may be used as in FIG. 2.

[0049] 2 and 3, the environmental device 10 may have the functions of the information processing device 60. That is, if the environmental device 10 is an air conditioner, any one of the outdoor unit 13a, the indoor unit 13b, and the remote control device 15 can estimate the CO2 concentration by performing the same processing as the information processing device 60 using a microcomputer or the like installed therein. The same applies when the environmental device 10 is a ventilation device. Also, the edge device 12, which will be described later with reference to FIG. 4, may have the functions of the information processing device 60.

[0050] <Gas concentration estimation system configuration> Next, the system configuration of the gas concentration estimation system 100 will be described with reference to Fig. 4. Fig. 4 is an example of a system configuration diagram of the gas concentration estimation system 100.

[0051] In the gas concentration estimation system 100, various types of environmental devices 10, such as air conditioners and ventilation devices, and a cloud-side information processing device 60 can communicate via a network N. The edge device 12, environmental devices 10, sensor switches 19, and user terminal 70 are installed on the customer side, and the information processing device 60 is installed in a cloud such as a data center or the Internet. Note that the edge device 12 is a device that centrally manages the environmental devices 10 and sensor switches 19, so the edge device 12 may be omitted.

[0052] As described above, the environmental device 10 is preferably a device that comes into contact with the air in a space where people are present, such as an air conditioner, a ventilation system, etc. Generally, the edge device 12 may be connected to security equipment, heat source equipment, a fire alarm, an AHU (air handling unit), a watt-hour meter, lighting, etc.

[0053] The environmental device 10 and the sensor switches 19 are controlled by the edge device 12. In other words, the edge device 12 applies required operations to the environmental device 10 and the sensor switches 19 so as to suit the purposes of the environmental device 10 and the sensor switches 19. The content of the control varies depending on the type of the environmental device 10 and the sensor switches 19. For example, if the environmental device 10 is an air conditioner, it may include all control related to the functions of the air conditioner, such as the cooling / heating mode, set temperature, ventilation volume, air volume, humidity, and air direction, which can generally be set on an air conditioner. For example, if the environmental device 10 is a ventilation device, it may include all control related to the functions of the ventilation device, such as ventilation volume. The sensor switches 19 may include a CO2 sensor 11.

[0054] The environmental device 10 collects operating data corresponding to the environmental device 10 and transmits it mainly periodically to the edge device 12. Periodically means, for example, once per minute, once per 10 minutes, once per 60 minutes, etc., but this may be set by the user or the information processing device 60. The operating data varies depending on the environmental device 10, but in the case of an air conditioner, for example, the operating data may include the high pressure and low pressure of the refrigerant, the refrigerant temperature, the fan rotation speed, and the CPU temperature of the microcomputer.

[0055] The edge device 12 is a controller that controls the environmental device 10 and the sensor switches 19. If the edge device 12 is not present, the information processing device 60 controls the environmental device 10 and the sensor switches 19.

[0056] The information processing device 60 may be one or more server devices. Although one information processing device 60 is shown in FIG. 4, the information processing device 60 may be installed in several separate units according to function. Furthermore, the functions of the information processing device 60 may be consolidated into one server device. Furthermore, multiple information processing devices 60 with the same function may be provided, and the multiple information processing devices 60 may communicate with each other and perform processing like a server cluster.

[0057] The information processing device 60 of this embodiment communicates with the edge device 12 and requests the edge device 12 to control the environmental device 10 and the sensor switches 19. The information processing device 60 receives information on the status of the environmental device 10 and the sensor switches 19 from the edge device 12, and if a malfunction or the like occurs, takes measures to resolve the malfunction or dispatches a service technician. The information processing device 60 also requests the edge device 12 to control the environmental device 10 and the sensor switches 19 in response to a request from a user terminal 70, and acquires these statuses and provides them to the user terminal 70. The information processing device 60 may also control the environmental device 10 in accordance with the estimated CO2 concentration.

[0058] The information processing device 60 may also have the functionality of a web server. In response to requests from client software (web clients) such as a web browser operated by a user, the web server provides the clients with screen information written in HTML files, XML, CSS files, JavaScript (registered trademark), etc. Applications that use the web mechanism in this way are called web applications.

[0059] It is preferable that the information processing device 60 is compatible with cloud computing, which is a form of use in which resources on a network are used without being aware of specific hardware resources.

[0060] The user terminal 70 may be, for example, a PC (Personal Computer), a smartphone, a tablet terminal, a PDA (Personal Digital Assistant), or a wearable PC (such as a sunglasses type or a wristwatch type). However, it is sufficient that the user terminal 70 has a communication function and can run a web browser or the like. Furthermore, instead of a web browser, the user terminal 70 may run a native app dedicated to the gas concentration estimation system 100.

[0061] <Hardware configuration of information processing device> Next, the hardware configuration of the information processing device 60 will be described with reference to Fig. 5. Fig. 5 is an example of a hardware configuration diagram of the information processing device 60. As shown in Fig. 5, the information processing device 60 has a processor 221, a memory 222, an auxiliary storage device 223, an I / F (Interface) device 224, a communication device 225, and a drive device 226. The hardware components of the information processing device 60 are connected to each other via a bus 227.

[0062] The processor 221 has various arithmetic devices such as a CPU (Central Processing Unit), etc. The processor 221 reads and executes various programs onto the memory 222. The processor 221 controls the information processing device 60 as a whole.

[0063] The memory 222 has a main storage device such as a read only memory (ROM) and a random access memory (RAM). The processor 221 and the memory 222 form a so-called computer, and the processor 221 executes various programs read onto the memory 222.

[0064] The auxiliary storage device 223 stores various programs and various data used when the processor 221 executes the various programs.

[0065] The I / F device 224 is a connection device that connects the information processing device 60 with a display device 230 and an operation device 240, which are examples of external devices. The display device 230 displays the internal state of the information processing device 60. The operation device 240 is used when an administrator of the information processing device 60 inputs various instructions to the information processing device 60.

[0066] The communication device 225 is a communication device for communicating with the edge device 12 and the user terminal 70 via the network N.

[0067] The drive device 226 is a device for loading a recording medium 250. The recording medium 250 here includes media that record information optically, electrically, or magnetically, such as a CD-ROM, a flexible disk, or a magneto-optical disk. The recording medium 250 may also include semiconductor memory that records information electrically, such as a ROM or flash memory.

[0068] The various programs to be installed in the auxiliary storage device 223 are installed, for example, by setting the distributed recording medium 250 in the drive device 226 and reading out the various programs recorded on the recording medium 250 by the drive device 226. Alternatively, the various programs to be installed in the auxiliary storage device 223 may be installed by being downloaded from the network N via the communication device 225.

[0069] <About the function> Next, the functional configuration of the gas concentration estimation system 100 will be described in detail with reference to Fig. 6. Fig. 6 is an example of a functional block diagram in which the functions of the information processing device 60 are explained by dividing them into blocks.

[0070] The information processing device 60 has a control unit 30 (an example of a control device) that estimates CO2 concentration, controls ventilation volume, and the like. The control unit 30 has a parameter correction unit 21, a CO2 concentration estimation unit 22, an equipment control unit 23, a number of people detection unit 24, a CO2 concentration reception unit 25, a number of people estimation unit 26, a warning output unit 27, and a parameter storage unit 29. These functions of the information processing device 60 are functions or means that are realized by the processor 221 in FIG. 5 executing a program installed in the information processing device 60. The parameter storage unit 29 may be implemented in the auxiliary storage device 223 or memory 222 in FIG. 5.

[0071] The CO2 concentration estimation unit 22 calculates the increase A in CO2 volume due to exhalation per unit time, the decrease B in CO2 volume due to ventilation and drafts of the environmental device 10 per unit time, the change ΔPr in CO2 volume in the space per unit time, and the CO2 concentration Pr after t seconds, etc. Details will be described later.

[0072] The number of people detection unit 24 detects the number of people in the space required for estimating the CO2 concentration. For example, the following method for detecting the number of people in the space may be adopted. If the space is a conference room, the time period and conference participants may be registered in the conference room's scheduling system, so the number of participants detection unit 24 obtains the number of participants for each time period from the scheduling system. If the space to be reserved and used, not limited to a conference room, has a system in which participants and their numbers are registered in advance, the number of people detection unit 24 can obtain the number of people present in the room. A camera installed at a door through which people enter and exit the space captures an image of, for example, a person's head. The number of people estimation unit 26 recognizes the heads captured in the image captured by the camera, and based on the head detection result, calculates the number of people in the space by subtracting the number of people leaving the space from the number of people entering the space. If a camera is installed in a position where it can capture the faces of people in the space, the number of people estimation unit 26 recognizes the faces in the images captured by the camera and detects the number of people in the space based on the face detection results. The camera may capture the head or back of the head. If a motion sensor that detects whether a person is seated is installed at each seat, the number of people estimating unit 26 detects the number of people in the space based on the seating signal transmitted from the seat. For example, in a company that has introduced a free address system, if a person registers the desk they use on the system, the number of people estimating unit 26 can obtain the number of people in the room from the system. The administrator may manually register the time periods and the expected number of people present in advance as a daily schedule.

[0073] The device control unit 23 controls the environmental device 10 so as not to decrease or increase the CO2 concentration, based on the CO2 concentration Pr estimated by the CO2 concentration estimation unit 22. That is, the device control unit 23 compares the CO2 concentration Pr with a threshold value to determine a ventilation volume, and instructs the environmental device 10 to ventilate at the determined ventilation volume.

[0074] The CO2 concentration receiving unit 25 receives the CO2 concentration Mv (detected value) input by the administrator to the user terminal 70. The CO2 concentration Mv is the CO2 concentration detected by the CO2 sensor. In other words, even if a CO2 sensor is not connected to the information processing device 60, if the administrator can refer to the CO2 concentration Mv detected by the CO2 sensor, the information processing device 60 can calculate the number of people in the room and correct parameters using the CO2 concentration Mv.

[0075] The number of people estimation unit 26 estimates the number of people in the space based on the CO2 concentration Mv. This allows the information processing device 60 to detect, for example, that the number of people accommodated in the space is equal to or greater than a specified number.

[0076] If it is determined that the space contains more than a specified number of people, the warning output unit 27 outputs a warning to that effect to the manager. The specified number of people is, for example, the number of people in the room at which it is difficult to control the concentration of gases such as CO2 so that it does not exceed a threshold even with ventilation, and may be set in advance.

[0077] The parameter correction unit 21 corrects the parameters for estimating the CO2 concentration Pr based on the difference between the estimated CO2 concentration Pr and the CO2 concentration Mv received from the administrator. These parameters are stored in the parameter storage unit 29, which will be described later. The parameters to be corrected are the air volume of drafts, the respiratory rate, or the exhaled air volume.

[0078] The parameters stored in the parameter storage unit 29 will be described with reference to Fig. 7. These parameters are used when calculating the CO2 concentration Pr. The parameters in Fig. 7 are also used when calculating the outdoor air load. The parameters are parameters related to the space (space volume, air volume of drafts), parameters related to people (time of day when people are present and number of people in the room, breathing conditions), parameters related to ventilation (rated ventilation air volume, control conditions), and parameters related to the outdoor air load (difference between indoor and outdoor specific enthalpy, heat exchange rate, COP).

[0079] The volume of the space is the volume of the space where people are present and the space is the target of ventilation. The unit of volume is "m 3 " The volume of the space is known, so it can be entered in advance.

[0080] The volume of draft is the volume of air that flows out of a space to the outside or flows into a space from the outside. The unit is, for example, "m 3 The exact value of the draft volume is unknown, but it is possible to input an estimated value in advance based on the number of doors, etc. The draft volume can be corrected as a parameter in equation (5).

[0081] The time periods when people are present and the number of people present are the main times when people are present in the space (when the space is being used). The unit is "people." The time periods when people are present are known, so they can be entered in advance.

[0082] The respiratory conditions are the average respiratory rate of the occupants, the average exhaled volume, and the average CO2 concentration in the exhaled air, Pr. The units are, for example, "times / 10 min" and "m 3 / 1 time" and "%". The breathing conditions are fixed values. The breathing rate and expiratory volume can be corrected as parameters of equation (5).

[0083] The ventilation rated air volume is the volume of air ventilated by the environmental equipment 10. The ventilation function allows for air volume adjustment (for example, extra strong, strong, weak, but two-stage control or four-stage or more control is also possible). The unit is "m 3 / h" x "number of units" of environmental equipment 10. Since the ventilation rated air volume is a controlled value, it can be entered in advance.

[0084] The control condition is a threshold value that is compared with the CO2 concentration Pr when controlling the environmental device 10. The unit is "ppm." For example, if the CO2 concentration Pr is over 900 [ppm], the environmental device 10 is controlled to operate at extra-strong. If the CO2 concentration Pr is over 800 [ppm] but not more than 900 [ppm], the environmental device 10 is controlled to operate at strong. If the CO2 concentration Pr is 800 [ppm] or less, the environmental device 10 is controlled to operate at weak. The control conditions are examples and are input in advance.

[0085] The indoor and outdoor specific enthalpy difference is calculated using the indoor temperature and humidity and the outdoor temperature and humidity. The indoor temperature and humidity shown in the figure are pre-entered according to the season, but are an example. The indoor temperature and humidity can also be values ​​detected by the indoor unit's sensor. Weather forecasts and detected values ​​published by the Japan Meteorological Agency and other organizations are used for the outdoor temperature and humidity. The outdoor temperature and humidity can also be values ​​detected by the outdoor unit's sensor. Since the enthalpy in the indoor / outdoor specific enthalpy difference represents the amount of heat, the indoor / outdoor specific enthalpy difference is the difference in the amount of heat between the indoor and outdoor air per 1 kg. The indoor / outdoor specific enthalpy difference is used when calculating the outdoor air load.

[0086] The heat exchange rate is the percentage of heat that the total heat exchanger can exchange with the room when ventilation is performed through the total heat exchanger. The unit is "%". The heat exchange rate is used when calculating the outdoor air load. The heat exchange rate is entered in advance as it is known as a specification of the total heat exchanger.

[0087] ·COP (Coefficient of Performance) represents the cooling and heating capacity (unit: [kW]) per 1 [kW] of power consumption under defined temperature conditions. Since COP is known as a specification of the environmental device 10, it is pre-input.

[0088] <Estimation of CO2 Concentration When CO2 Sensor Is Not Used> The above equations (1) to (4) for estimating the CO2 concentration Pr without using a CO2 sensor will be described in detail. Figure 8(a) shows the calculation formula for the change amount ΔPr of the CO2 volume in space per unit time without using a CO2 sensor. As shown in Equation 321 of Figure 8(a), the change amount ΔPr can be calculated by "increase in CO2 volume due to respiration - decrease in CO2 volume due to ventilation etc.". Equation 322 is the expansion of the second term of Equation 321. The second term of Equation 321 is expanded into terms of ventilation and crack wind, such as "decrease in CO2 volume due to ventilation + decrease in CO2 volume due to crack wind".

[0089] When the first term of Equation 321 and the second term of Equation 322 are further expanded, the change amount ΔPr is calculated by Equation (5). Equations (4) and (5) are examples of model equations for estimating the CO2 concentration. ΔPr = (CO2 concentration in exhaled breath - CO2 concentration in space) × exhaled breath volume × number of breaths per unit time × N people -{(CO2 concentration in the room - CO2 concentration in the outside air) × air volume of the environmental device + (CO2 concentration in the room - CO2 concentration in the outside air) × air volume of the crack wind}……(5) The first term of Equation (5) is the increase amount A of CO2 due to exhalation shown in Equation (1). The second term of Equation (5) is "decrease amount of CO2 due to ventilation of the environmental device per unit time + decrease amount of CO2 due to crack wind per unit time B" shown in Equation (2). Note that Equation (5) corresponds to Equation (3).

[0090] When the change amount ΔPr of the CO2 volume is known, the CO2 concentration Pr in the space after t seconds can be estimated by Equation (4) in Figure 8(b). Pr ← Pr + (ΔPr / space volume) × t ……(4) Supplement regarding the unit time. Equation (5) is premised on the assumption that the number of people in the room does not change (or does not change significantly) during the unit time. However, if the unit time is short, the change amount of the CO2 concentration Pr will also be small, and there is a risk that the error will be large. Therefore, the unit time is preferably set to the minimum time during which a certain change amount of the CO2 concentration Pr can be expected and the number of people in the room does not change. For example, the information processing device 60 calculates how often the number of people in the room changes from the past data of the number-of-people detection unit 24. The information processing device 60 sets the longer of the shortest time when the number of people in the room changes and the time during which a certain change amount of the CO2 concentration Pr can be expected as the unit time. Note that the unit time may vary depending on the time zone or the like.

[0091] <Estimation process of CO2 concentration> Next, referring to FIG. 9, a process of estimating the CO2 concentration Pr without using a CO2 sensor will be described. FIG. 9 is a flowchart for explaining a process in which the information processing device 60 estimates the CO2 concentration Pr and controls the environmental device 10 based on the estimated CO2 concentration Pr. The process of FIG. 9 starts during a time period when no person is present in the space. This is because it is preferable to start the process of FIG. 9 when the initial value of the CO2 concentration Pr set in step S11 coincides with the outside air or is of the same degree. Also, the environmental device 10 may start ventilation with an arbitrary ventilation volume.

[0092] First, the CO2 concentration estimation unit 22 sets the initial value of the CO2 concentration Pr as the CO2 concentration Pr (S11). Since the initial value of the CO2 concentration Pr may be the CO2 concentration of the outside air, a known fixed value such as, for example, 0.045% (450 [ppm]) is used as the initial value Pr.

[0093] Next, the CO2 concentration estimation unit 22 calculates the increase amount A of the CO2 volume due to exhalation per unit time (S12). The increase amount A of the CO2 volume is calculated by Equation (1).

[0094] Next, the CO2 concentration estimation unit 22 calculates "the amount of CO2 volume reduction due to ventilation of the environmental equipment per unit time + the amount of CO2 volume reduction B due to drafts per unit time" (S13). The amount of reduction B is calculated using equation (2).

[0095] Next, the CO2 concentration estimation unit 22 calculates the amount of change ΔPr (ΔPr=AB) in the volume of CO2 in the space per unit time (S14). The amount of change ΔPr in the volume of CO2 is calculated by equation (3).

[0096] Next, the CO2 concentration estimation unit 22 calculates the amount of change C (C=ΔPr / V) in the CO2 concentration Pr from the amount of change ΔPr and the space volume V (S15).

[0097] Next, the CO2 concentration estimation unit 22 calculates the CO2 concentration Pr after t seconds (Pr=Pr+C×t) (S16). The CO2 concentration Pr after t seconds is calculated by equation (4).

[0098] Next, the device control unit 23 compares the CO2 concentration Pr after t seconds with each threshold value (control condition in FIG. 7) to determine whether it has exceeded the threshold value (S17).

[0099] The device control unit 23 controls the ventilation volume of the environmental device 10 according to the threshold value that the CO2 concentration Pr has exceeded after t seconds (S18). For example, according to the parameter storage unit 29, the device control unit 23 controls the ventilation volume to be extra strong when the CO2 concentration Pr is greater than 900 [ppm], controls the ventilation volume to be strong when the CO2 concentration Pr is greater than 800 [ppm] and less than 900 [ppm], and controls the ventilation volume to be weak when the CO2 concentration Pr is less than 800 [ppm].

[0100] The CO2 concentration estimation unit 22 repeatedly executes the process of Fig. 9 every time t seconds elapse (S19). In this way, the CO2 concentration estimation unit 22 of this embodiment can estimate the CO2 concentration Pr t seconds from now, enabling feedforward control based on prediction. When a CO2 sensor is used, the current CO2 concentration Pr is detected, so feedback control is performed and the ventilation volume is controlled after the actual CO2 concentration Pr exceeds a threshold, so there is a risk that the CO2 concentration Pr will exceed the threshold for a certain period of time.

[0101] In step S16, the CO2 concentration Pr is estimated based on the current ventilation rate, and in step S18, the next ventilation rate is determined based on this CO2 concentration Pr. Furthermore, when the process of Figure 9 is executed next time, the CO2 concentration Pr is estimated based on the next ventilation rate, and in step S18, the ventilation rate after that is determined based on this CO2 concentration Pr. In this way, since the control of the ventilation rate and the estimation of the CO2 concentration Pr are repeated, the ventilation rate is determined appropriately and the accuracy of the CO2 concentration Pr can be maintained.

[0102] Furthermore, the information processing device 60 preferably repeats the process of FIG. 9 for 24 hours. As shown in step S11 of FIG. 9, the CO2 concentration of the outdoor air is used as the initial value of the CO2 concentration Pr. In an office where daytime shifts are common, the CO2 concentration Pr of the space in the morning decreases to the CO2 concentration of the outdoor air even when the environmental device 10 is turned off. However, the CO2 concentration may not decrease completely by the time employees arrive at work in the morning. For example, in a space where people may be present until late at night or dawn, the CO2 concentration may not decrease completely by the time employees arrive at work. In this case, setting the CO2 concentration of the outdoor air as the initial value results in an initial value that differs from the actual CO2 concentration Pr of the space, and the CO2 concentration Pr estimated by the process of FIG. 9 may also differ from the actual CO2 concentration. Therefore, by having the information processing device 60 repeat the process of FIG. 9 for 24 hours, it is possible to suppress the discrepancy between the actual CO2 concentration and the estimated CO2 concentration Pr caused by the setting of the initial value.

[0103] Note that even if the information processing device 60 continues to estimate the CO concentration 24 hours a day, the ventilation function may be turned off during times when no one is present. In this way, the information processing device 60 can suppress an increase in power consumption while maintaining the accuracy of the estimated CO concentration Pr.

[0104] <Example of estimated CO2 concentration Pr> 10 is an external view of the remote control device 15. The remote control device 15 is installed in a space. The remote control device 15 is associated with an environmental device 10 and is installed in the same space as the corresponding environmental device 10. The remote control device 15 is fixed to a wall or the like of the space via a mounting member. The remote control device 15 is electrically connected to the corresponding indoor unit 13b via the network NW2.

[0105] The remote control device 15 functions as a command input device for inputting commands related to various settings to the environmental equipment 10. The remote control device 15 also functions as a display device for displaying various information. The various settings performed by commands input to the remote control device 15 include, for example, operation settings such as the set temperature, operation mode, set air volume, set air direction, and operation schedule, initial settings set at the time of installation or maintenance, and settings of the display mode on the display unit 51.

[0106] The remote control device 15 has a display unit 51. The display unit 51 displays an installation location 52, a current information display field 53, a message display field 54, a setting button 55, etc. The current information display field 53 displays a current airflow rate 53a, airflow direction 53b, set temperature 53c, outside air temperature 53d, CO2 concentration Pr, and room temperature 53f. The CO2 concentration Pr is the CO2 concentration calculated by the information processing device 60 after the elapse of a unit time, but the CO2 concentration before the elapse of the unit time (one cycle before the processing in FIG. 9) may be displayed instead. The remote control device 15 may output the CO2 concentration Pr by voice in response to a user operation, or may output the CO2 concentration Pr by voice when the CO2 concentration Pr changes.

[0107] The display unit 51 may display the history of past CO2 concentration Pr in chronological order as a graph or numerical values. The display unit 51 may also display the number of people in the space used in the calculation or estimated. If the CO2 concentration Pr exceeds a certain value (e.g., 1000 ppm) due to a lack of ventilation, the display unit 51 may display that fact in the message display field 54.

[0108] 10, the remote control device 15 displays the CO2 concentration Pr, but the user terminal 70 may also display it. The user terminal 70 can connect to the information processing device 60 and display the CO2 concentration Pr of each space, past history, etc., using a web application or the like. The information processing device 60 may also send the CO2 concentration Pr by email to the administrator's email address, or may display the CO2 concentration on a display placed in the space. <Effect of ventilation control using CO2 concentration Pr in this embodiment> FIG. 11 shows graphs of various indices when constant airflow ventilation control and ventilation control are performed using a CO2 concentration Pr. Constant airflow ventilation control is an existing ventilation method in which ventilation is performed at a constant ventilation volume regardless of the CO2 concentration. Ventilation control using a CO2 concentration Pr is ventilation control according to this embodiment, and is a ventilation method in which the ventilation volume is controlled according to a CO2 concentration Pr estimated without using a CO2 sensor.

[0109] Figure 11 shows the changes in CO2 concentration (constant airflow ventilation control) 301, CO2 concentration (ventilation control using CO2 concentration Pr) 302, airflow (constant airflow ventilation control) 303, airflow (ventilation control using CO2 concentration Pr) 304, and number of people in the room 305 over time.

[0110] Ventilation begins at time t1 and ends at time t3. From around time t2, the number of people in the space gradually increases. It can be seen that the airflow (ventilation control using CO2 concentration Pr) 304 increases or decreases in accordance with the number of people in the room. Furthermore, the CO2 concentration (constant airflow ventilation control) 301 increases as the number of people in the room increases and decreases as the number of people in the room decreases, making the CO2 concentration prone to fluctuations. On the other hand, the CO2 concentration (ventilation control using CO2 concentration Pr) 302 remains at approximately 800 ppm regardless of the number of people in the room, demonstrating that a CO2 concentration sufficiently low relative to a specified value such as 1000 ppm can be maintained.

[0111] Furthermore, when comparing air volume (constant air volume ventilation control) 303 and air volume (ventilation control using CO2 concentration Pr) 304, it can be seen that, on average, air volume (constant air volume ventilation control) 303 is higher and consumes more power.

[0112] In this way, the information processing device 60 of this embodiment estimates the CO2 concentration Pr, thereby reducing power consumption, appropriately controlling the ventilation volume, and maintaining the CO2 concentration below a specified value.

[0113] Furthermore, as the number of people occupying the room 305 decreases toward the end of regular work hours (time t3), both the CO2 concentration (constant airflow ventilation control) 301 and the CO2 concentration (ventilation control using CO2 concentration Pr) 302 gradually decrease. The reason why the CO2 concentration (constant airflow ventilation control) 301 and the CO2 concentration (ventilation control using CO2 concentration Pr) 302 continue to decrease after ventilation ends at time t3 is because ventilation occurs due to drafts. There is also a concentration difference 306 between the CO2 concentrations at time t4 and time t1, and it can be confirmed that this concentration difference 306 decreases to the CO2 concentration of the outside air by the morning of the following day.

[0114] <Calculating the number of people H in a space> Next, a method will be described in which the information processing device 60 calculates the number of people H in the space when the administrator inputs the CO2 concentration Mv detected by the CO2 sensor into the information processing device 60. The three equations for calculating the CO2 concentration Pr are listed again. A = (CO2 concentration in exhaled air - CO2 concentration in air) x exhaled volume x number of breaths per unit time x N people ……(1) B = (CO2 concentration in the room - CO2 concentration in the outside air) x air volume of the environmental equipment + (CO2 concentration in the room - CO2 concentration in the outside air) x draft volume ……(2) ΔPr=AB ……(3) The CO2 concentration receiving unit 25 receives the CO2 concentration Mv detected by the CO2 sensor from the administrator. There are no particular restrictions on when the administrator can input the CO2 concentration Mv, and the ventilation function may be OFF. Since ΔPr in equation (3) is the amount of change in the volume of CO2, ΔPr on the left side of equation (3) can be calculated as follows: ΔPr = change in CO2 concentration per unit time × space volume... (6) When this ΔPr is substituted into the left side of equation (3), the only remaining variable is the number of people H in the room, so the number-of-people estimation unit 26 can calculate the number of people H in the room from equations (1) and (2).

[0115] Fig. 12 is a flowchart illustrating the process by which the number of people estimation unit 26 estimates the number of people in a space when the manager inputs the CO2 concentration Mv measured by the CO2 sensor into the information processing device 60. The process in Fig. 12 may be performed before, after, or in parallel with the process in Fig. 9, for example, or may be performed independently of the process in Fig. 9.

[0116] First, the administrator inputs the CO2 concentration Mv detected by the CO2 sensor to the information processing device 60 via the user terminal 70. The CO2 concentration receiving unit 25 receives the CO2 concentration Mv (S21). Note that, since ΔPr in equation (6) calculates the "amount of change in CO2 concentration per unit time," the administrator inputs the CO2 concentrations Mv before and after the unit time has elapsed.

[0117] Next, the number of people estimation unit 26 calculates the difference in the CO2 concentration Mv before and after the unit time, that is, the amount of change in the CO2 concentration Mv that has changed over the unit time (S22).

[0118] Next, the number-of-people estimation unit 26 multiplies the amount of change in the CO2 concentration Mv in step S22 by the space volume V to calculate the amount of change in the volume of CO2 ΔPr (S23).

[0119] Next, the number of people estimation unit 26 calculates the number of people H in the room from the formulas (1) to (3) and the amount of change in the volume of CO2 ΔPr (S24).

[0120] Next, the warning output unit 27 determines whether the estimated number of people H in the room exceeds a predetermined number of people (S25). The predetermined number of people is, for example, a capacity set in advance for the space.

[0121] If the determination in step S25 is Yes, the warning output unit 27 outputs a message indicating that the estimated number of people H in the room exceeds a specified number (S26). The output method may be a display on the user terminal 70 or a display on the remote control device 15. The warning output unit 27 may also send an email to the administrator's email address or display the message on a display arranged in the space. In this way, the information processing device 60 can maintain the number of people in the space at or below a specified number. The specified number of people can be set arbitrarily by the administrator.

[0122] <<Parameter correction>> Next, correction of parameters used by the CO2 concentration estimation unit 22 to estimate the CO2 concentration will be described. As shown in equations (1) to (4), the air volume of the draft, the respiratory rate, and the CO2 concentration in the exhaled breath are used to estimate the CO2 concentration Pr. Therefore, if the estimated CO2 concentration Pr differs significantly from the CO2 concentration Mv detected by the CO2 sensor, the parameters may not be appropriate. Therefore, as shown below, the parameter correction unit 21 corrects the parameters for estimating the CO2 concentration Pr.

[0123] Fig. 13 is a flowchart illustrating the process of correcting parameters by the parameter correction unit 21. The process of Fig. 13 is performed when the CO2 concentration reception unit 25 receives the CO2 concentration Mv.

[0124] First, the parameter corrector 21 acquires the CO2 concentration Mv received by the CO2 concentration receiver 25 and the most recently estimated CO2 concentration Pr (S31).

[0125] The parameter corrector 21 determines whether the difference between the CO2 concentration Pr and the CO2 concentration Mv (CO2 concentration Pr-CO2 concentration Mv) is equal to or greater than a threshold value (S32).

[0126] If the determination in step S32 is Yes, the parameter corrector 21 performs one or more of the following: increasing the air volume of the gap, reducing the number of breaths, or reducing the exhaled air volume (S33).

[0127] If the determination in step S32 is No, the parameter corrector 21 determines whether the difference between the CO2 concentration Mv and the CO2 concentration Pr (CO2 concentration Mv-CO2 concentration Pr) is equal to or greater than a threshold value (S34).

[0128] If the determination in step S34 is Yes, the parameter corrector 21 performs one or more of the following: reducing the air volume of the gap, increasing the number of breaths, or increasing the exhaled air volume (S35).

[0129] In this way, by inputting the CO2 concentration Mv detected by the CO2 sensor, the parameter correction unit 21 can correct the parameters, so that even if a CO2 sensor is not connected to the information processing device 60, the information processing device 60 can estimate the CO2 concentration Pr with high accuracy.

[0130] Which parameter to correct among the parameters to be corrected, the airflow rate of the draft, the respiratory rate, or the expiratory volume, may be determined in advance. For example, the parameter correcting unit 21 switches between the airflow rate of the draft, the respiratory rate, and the expiratory volume in order and corrects one of them each time the process of FIG. 13 is executed. That is, the parameter correcting unit 21 corrects the airflow rate of the draft the first time, corrects the respiratory rate the second time, and corrects the expiratory volume the third time. The parameter correcting unit 21 returns to the airflow rate of the draft the fourth time. Alternatively, the parameter correcting unit 21 may correct all of the airflow rate of the draft, the respiratory rate, and the expiratory volume little by little (one-third of the amount corrected when correcting one parameter in one correction) in one run of the process of FIG. 13.

[0131] <Major Effects> The environmental device 10 of this embodiment can predict the CO2 concentration Pr in a space without using a CO2 sensor. The environmental device 10 can estimate the CO2 concentration Pr in the future unit time by accumulating the change amount ΔPr in the CO2 concentration Pr over a unit time with the current CO2 concentration Pr. Furthermore, since the environmental device 10 can predict the CO2 concentration Pr t seconds from now, feedforward control becomes possible, which may be more advantageous than feedback control using a CO2 sensor. For example, it is possible to suppress an increase in the CO2 concentration in the space before the CO2 concentration Pr exceeds a certain amount.

[0132] Furthermore, if a CO2 sensor is available to the manager (if the CO2 concentration in the space can be measured) even though it is not connected to the information processing device 60, the manager can input the value detected by the CO2 sensor into the information processing device 60, which can then reverse-calculate the number of people present in the room. Furthermore, the information processing device 60 can correct the parameters (air volume of draft, exhaled air volume, and number of breaths per unit time) in equations (1) and (2) by comparing the detected value of CO2 concentration with the estimated value.

[0133] [Second embodiment] In the first embodiment, the information processing device 60 that estimates the CO concentration Pr and controls the ventilation volume was described. In the present embodiment, the information processing device 60 that estimates the CO concentration Pr and presents the annual ventilation volume and power consumption reduced by controlling the ventilation volume will be described.

[0134] <About the function> 14 is an example of a functional block diagram for explaining functions of the information processing device 60 of this embodiment by dividing them into blocks. Note that the explanation of FIG. 14 may mainly focus on the differences from FIG.

[0135] 6, the information processing device 60 has an air volume calculation unit 31, a power consumption calculation unit 32, and a presentation unit 33. The air volume calculation unit 31 calculates the air volume (an example of a first air volume) of the environmental device 10 for a certain period (e.g., one year) when it is assumed that the device continues to operate at a predetermined ventilation volume (e.g., a ventilation volume that matches the maximum number of people). Furthermore, the air volume calculation unit 31 calculates the air volume (an example of a second air volume) of the environmental device 10 for a certain period (e.g., one year) based on a number-of-people model (see FIG. 15) described later, and assuming that the ventilation volume is controlled by the method described in the first embodiment.

[0136] The power consumption calculation unit 32 calculates the power consumption consumed at the first airflow rate (an example of first power consumption) and the power consumption consumed at the second airflow rate (an example of second power consumption). Because ventilation generates an outside air load, it is preferable that the power consumption calculation unit 32 calculates the power consumption taking the outside air load into consideration.

[0137] The presentation unit 33 creates a screen or document including the difference between the first air volume and the second air volume, the difference between the first power consumption and the second power consumption, and the difference in electricity rates, and presents it to the seller or customer.

[0138] <Number of people in the room model> The occupancy number model will be described with reference to FIG. 15. FIG. 15 shows an example of a model of the number of occupants in a certain space at a customer's place. The occupancy number model is created by the seller based on interviews with customers who are considering introducing the gas concentration estimation system 100 and design drawings (maximum number of people). If there is a record of the number of occupants per time period from the past, the information processing device 60 may use this to create the occupancy number model. For example, the information processing device 60 may obtain the number of occupants per time period by day of the week from the past records and use the average for each day of the week and time period as the occupancy number model.

[0139] The occupancy model is a table that contains the number of people in the room for each time period. In FIG. 15, this table is shown in the form of a bar graph. While FIG. 15 shows the number of people in the room for each hour in a graph, it is preferable to convert the number of people in the room for each unit of time into data. Even for customers who have not installed the gas concentration estimation system 100, the number of people in the room for each time period is known in advance from the occupancy model, so the information processing device 60 can simulate the ventilation volume.

[0140] <Displaying the difference between the first and second airflow volumes, and the difference between the first and second power consumption> 16 is a flowchart illustrating a process in which the information processing device 60 presents the difference between the first air volume and the second air volume, and the difference between the first power consumption and the second power consumption. The process in FIG. 16 may be executed at any timing by the seller. The operating time of the environmental device 10 in the simulation is set to 15 hours from 6:00 to 21:00.

[0141] First, the air volume calculation unit 31 calculates the air volume (first air volume) of the environmental device 10 for one year assuming that it will continue to operate at a predetermined ventilation volume (S41). Note that one year is just an example, and it may be one day, one week, one month, six months, etc. The predetermined ventilation volume may be an air volume roughly calculated based on the maximum number of people that can be present in the space, and may be set by the seller. The predetermined ventilation volume may be, for example, 900 m 3 / h] etc. Therefore, the first air volume = 900 [m 3 / h] x 15 hours x annual business days.

[0142] Next, the air volume calculation unit 31 calculates the air volume (second air volume) of the environmental device 10 for one year when the ventilation volume is adjusted based on the CO2 concentration Pr (S42). Therefore, the CO2 concentration estimation unit 22 obtains the number of people H in the room from the number of people model, and performs the process of FIG. 9. The device control unit 23 calculates the ventilation volume for each unit time as shown in step S18 of FIG. 9, and integrates the ventilation volume for each unit time from 6:00 to 21:00. The integrated value is expressed as S[m 3 ], so the second air volume = S [m 3 ]× business days per year.

[0143] Next, the power consumption calculation unit 32 calculates the first power consumption consumed at the first airflow rate and the power consumption consumed at the second airflow rate (S43). This calculation takes into account the outdoor air load [W]. Equation (7) is a formula for calculating the outdoor air load, and Equation (8) is a formula for calculating the power consumption. Outdoor air load = air volume × 0.33 × indoor / outdoor specific enthalpy difference × (1 - heat exchange rate) … (7) Power consumption = (outdoor air load / air conditioner COP)...(8) Equation (7) applies when the ventilated air passes through a total heat exchanger. When the ventilated air does not pass through a total heat exchanger, equation (7) can be expressed as "air volume x 0.33 x difference in indoor / outdoor specific enthalpy."

[0144] The presentation unit 33 presents the difference between the first air volume and the second air volume, and the difference between the first power consumption and the second power consumption (S44). The presentation unit 33 may further multiply the first power consumption and the second power consumption by the electricity rate unit price to present the difference between the respective annual electricity rates (the first electricity rate and the second electricity rate). Electricity cost = Power consumption × Electricity cost (9) Fig. 17 shows the difference 311 between the first airflow rate and the second airflow rate, the difference 312 between the first power consumption and the second power consumption, and the difference 313 between the first electricity rate and the second electricity rate, all presented by the presentation unit 33. The screen of Fig. 17 can be displayed on, for example, a user terminal 70 used by a seller or a customer. As shown in Fig. 17, airflow rates 314, 315, power consumption 316, 317, and electricity rates 318, 319 are presented for both the constant airflow rate case and the CO2 concentration ventilation control case. In addition, the difference 311 between the constant airflow rate case and the CO2 concentration ventilation control case, the difference 312 between the power consumption case and the electricity rate 313 are also displayed.

[0145] By looking at such specific figures, customers considering introducing the gas concentration estimation system 100 can know in advance the effects of the introduction, which makes internal approvals and other procedures smoother.

[0146] <Major Effects> According to this embodiment, not only in cases where the CO2 sensor is not connected to the information processing device 60, but also in cases where the gas concentration estimation system 100 has not been installed, it is possible to simulate the air volume when the ventilation volume is controlled according to the CO2 concentration Pr and predict the reduction effect on power consumption, etc.

[0147] <Other application examples> The best mode for carrying out the present disclosure has been described above using examples, but the present disclosure is not limited to these examples in any way, and various modifications and substitutions can be made within the scope that does not deviate from the gist of the present disclosure.

[0148] For example, the environmental device 10 may estimate the concentration of a gas other than CO2 (which increases with exhalation). For example, an aerosol containing various substances exhaled with exhalation may be used. The environmental device 10 may also estimate the concentration of a specific virus. In this case, the number of infected people is used as the number of people in the room H.

[0149] Furthermore, the unit time does not have to be fixed at 10 minutes, but can be changed depending on the time period. For example, the unit time can be shortened during periods when there is a lot of people coming and going, and lengthened during periods when there is little. By shortening the unit time during periods when there is a lot of people coming and going, the number of people in the room within the unit time is less likely to change, improving the accuracy of the estimated CO2 concentration.

[0150] In addition, the configuration examples in Fig. 6 and the like are divided according to main functions to facilitate understanding of the processing by the information processing device 60. The present disclosure is not limited by the manner in which the processing units are divided or the names of the processing units. The processing of the information processing device 60 can also be divided into more processing units depending on the processing content. Furthermore, it can also be divided so that one processing unit includes more processes.

[0151] Additionally, the devices described in the examples are merely illustrative of one of several computing environments for implementing the embodiments disclosed herein. In one embodiment, information processing device 60 includes multiple computing devices, such as a server cluster. The multiple computing devices are configured to communicate with each other via any type of communication link, including a network, shared memory, etc., and perform the processes disclosed herein.

[0152] The functions of the present disclosure described above can be realized not only by software processing through the execution of a program, but also by one or more processing circuits. Here, the term "processing circuit" in this specification includes a processor programmed to perform each function by software, such as a processor implemented by an electronic circuit, as well as devices such as an ASIC (Application Specific Integrated Circuit), a DSP (Digital Signal Processor), an FPGA (Field Programmable Gate Array), and a conventional circuit module designed to perform each of the functions described above.

[0153] <Reasons for the effect> The first aspect of the present disclosure first "uses the gas concentration of the outside air as the initial value of the gas concentration before the update," so that a correct initial value of the gas concentration can be set even without a gas concentration sensor, and then "calculates the amount of change in the gas concentration per unit time using the number of people occupying the space" for this initial value, and "updates the gas concentration by accumulating the amount of change with the gas concentration in the space before the update," so that the gas concentration is estimated for each unit time when it is assumed that the number of people occupying the space will not change, and is accumulated, so that a gas concentration can be estimated with high accuracy even without a gas concentration sensor.

[0154] The second aspect of the present disclosure "outputs the updated gas concentration," so that the gas concentration can be displayed or output as audio, allowing the manager or people in the room to understand the gas concentration.

[0155] The third aspect of the present disclosure "corrects the parameters of a model equation that calculates the amount of change in gas concentration per unit time using the number of people in the space," so that the parameters of the model equation can be corrected using the input gas concentration, and even without a gas concentration sensor, appropriate parameters can be set for the space, allowing for accurate estimation of gas concentration.

[0156] In the fourth aspect of the present disclosure, "the parameters of the model formula are the air volume of draft, the number of breaths per unit time, and the exhaled air volume," and by comparing the magnitude of the updated gas concentration with the input gas concentration, one or more of the parameters of the model formula, the air volume of draft, the number of breaths per unit time, and the exhaled air volume, can be adjusted to estimate the gas concentration with high accuracy.

[0157] The fifth aspect of the present disclosure obtains the number of people present in a room using a camera, a sensor, a schedule system, manual input, etc., so that the number of people present in the room can be obtained accurately and gas concentrations can be estimated with high precision.

[0158] The sixth aspect of the present disclosure "continues updating the gas concentration every unit time for 24 hours," thereby eliminating the need to set an initial value every morning, and estimating the gas concentration continues for 24 hours even in spaces where people are present at night. This allows for accurate estimation of the gas concentration even if the gas concentration does not decrease to the same level as that of the outside air by the time people arrive at work in the morning.

[0159] The seventh aspect of the present disclosure calculates the gas concentration based on the ventilation rate and the number of people in the space, and then repeatedly estimates the ventilation rate based on this gas concentration. Therefore, if the parameters are appropriate, it is expected that the accuracy of the gas concentration will gradually improve.

[0160] The eighth aspect of the present disclosure "uses an estimated value of ventilation volume other than that ventilated by the environmental equipment," so that gas concentrations can be estimated accurately even when the environmental equipment ventilates naturally in addition to ventilating by controlling the ventilation volume.

[0161] The ninth aspect of the present disclosure estimates the "air volume of drafts" in addition to the ventilation volume controlled by the environmental device, so that gas concentrations can be estimated accurately even in spaces with a lot of people coming and going (a lot of drafts).

[0162] The tenth aspect of the present disclosure "calculates a first air volume of the environmental equipment for a predetermined period of time when it is assumed that the equipment will continue to operate at a predetermined ventilation volume, calculates the gas concentration based on a predetermined model of the number of people present, calculates a second air volume of the environmental equipment for a predetermined period of time when the ventilation volume is adjusted according to the calculated gas concentration, and calculates a first power consumption consumed at the first air volume and a second power consumption consumed at the second air volume," so that the amount of power consumption that can be reduced by the ventilation control of the present disclosure can be expressed as a numerical value.

[0163] The eleventh aspect of the present disclosure "calculates the first power consumption and the second power consumption using the outdoor air load," so that it is possible to calculate more accurate power consumption taking the outdoor air load into consideration.

[0164] The twelfth aspect of the present disclosure clarifies the model formula, and the model formula enables accurate estimation of gas concentration. [Explanation of symbols]

[0165] 10 Environmental equipment 60 Information processing equipment 70 user terminals 100 Gas concentration estimation system

Claims

1. A gas concentration estimation system that estimates the concentration of a predetermined gas in a space ventilated by an environmental device, a control unit that calculates a change in gas concentration per unit time using the number of people in the space; the control unit updates the gas concentration by accumulating the amount of change to the gas concentration in the space before updating; A common known gas concentration in outside air is used as an initial value of the gas concentration before updating, The control unit calculates the gas concentration using the current ventilation volume of the environmental device and the number of people in the space, and determines the next ventilation volume based on the gas concentration. Furthermore, the gas concentration is calculated using the next ventilation volume and the number of people in the space, and the next ventilation volume is determined based on the gas concentration. Gas concentration estimation system.

2. The gas concentration estimation system according to claim 1 , wherein the control unit outputs the updated gas concentration.

3. the control unit receives an input of a gas concentration detected by a gas sensor when a person is present in the space; 3. The gas concentration estimation system according to claim 1, wherein if there is a difference between the updated gas concentration and the input gas concentration that is equal to or greater than a threshold value, parameters of a model formula that calculates the amount of change in gas concentration per unit time using the number of people occupying the space are corrected.

4. The parameters of the model formula are the air volume of the draft, the number of breaths per unit time, and the expiratory volume, When the input gas concentration is greater than the updated gas concentration, the control unit performs at least one of reducing the air volume of the gap, increasing the number of breaths per unit time, or increasing the exhaled air volume; 4. The gas concentration estimation system of claim 3, wherein when the input gas concentration is smaller than the updated gas concentration, at least one of increasing the air volume of the gap, reducing the number of breaths per unit time, or reducing the exhaled air volume is performed.

5. 2. The gas concentration estimation system of claim 1, wherein the control unit acquires the number of people present in the space by detecting people entering and exiting the space photographed by a camera, detecting people appearing in an image of the space, detecting people detected by a human presence sensor installed in a seat, people using the space acquired from a scheduling system, or manually inputting the number of people present.

6. The gas concentration estimation system according to claim 1 , wherein the control unit continues updating the gas concentration for each unit time for 24 hours.

7. The gas concentration estimation system according to claim 1 , wherein the control unit uses an estimated value of a ventilation amount other than ventilation by the environmental device when calculating the gas concentration.

8. The gas concentration estimation system according to claim 7 , wherein the estimated ventilation volume is a volume of draft air.

9. the control unit calculates a first airflow rate of the environmental device for a predetermined period of time assuming that the environmental device will continue to operate at a predetermined ventilation rate; calculating the gas concentration based on a predetermined occupancy model, and calculating a second airflow rate of the environmental device for a period equal to the predetermined period when a ventilation rate is adjusted according to the calculated gas concentration; calculating a first power consumption consumed at the first airflow rate and a second power consumption consumed at the second airflow rate; The gas concentration estimation system according to claim 1 , further comprising: displaying a difference between the first airflow rate and the second airflow rate, or a difference between the first power consumption and the second power consumption.

10. 10. The gas concentration estimation system according to claim 9, wherein the control unit calculates an outside air load from each of the first air volume and the second air volume, and calculates the first power consumption and the second power consumption using the outside air load.

11. the predetermined gas is CO2, The control unit calculates the increase A in CO2 volume due to breathing as follows: A = (CO2 concentration in exhaled air - CO2 concentration in the space) x exhaled air volume x number of breaths per unit time x number of people in the room. The amount of CO2 volume reduction B due to ventilation and drafts is B = (CO2 concentration in the room - CO2 concentration in the outside air) x ventilation air volume + (CO2 concentration in the room - CO2 concentration in the outside air) x draft volume Calculate by The change in volume of CO2 per unit time in the space, ΔPr, is ΔPr = A - B Calculate by The CO2 concentration Pr after the unit time has elapsed is Pr←Pr+(ΔPr / space volume)×the unit time The gas concentration estimation system according to claim 1 , wherein the calculation is performed by:

12. the control unit uses a known fixed value of the gas concentration as the initial value of the gas concentration before updating. The gas concentration estimation system according to claim 1 .

13. A gas concentration estimation system that estimates the concentration of a predetermined gas in a space ventilated by an environmental device, a control unit that calculates a change in gas concentration per unit time using the number of people in the space; the control unit updates the gas concentration by accumulating the amount of change to the gas concentration in the space before updating; A general gas concentration other than that measured by the sensor is used as the initial value of the gas concentration before updating, The control unit calculates the gas concentration using the current ventilation volume of the environmental device and the number of people in the space, and determines the next ventilation volume based on the gas concentration. Furthermore, the gas concentration is calculated using the next ventilation volume and the number of people in the space, and the next ventilation volume is determined based on the gas concentration. Gas concentration estimation system.

14. A gas concentration estimation method performed by a gas concentration estimation system that estimates the concentration of a predetermined gas in a space ventilated by an environmental device, comprising: the control unit calculates the amount of change in gas concentration per unit time using the number of people in the space; updating the gas concentration by accumulating the change amount to the gas concentration in the space before updating; A common known gas concentration in outside air is used as an initial value of the gas concentration before updating, The control unit calculates the gas concentration using the current ventilation volume of the environmental device and the number of people in the space, and determines the next ventilation volume based on the gas concentration. Furthermore, the gas concentration is calculated using the next ventilation volume and the number of people in the space, and the next ventilation volume is determined based on the gas concentration. Gas concentration estimation method.

15. A control device that estimates the concentration of a predetermined gas in a space ventilated by an environmental device, Calculating the change in gas concentration per unit time using the number of people in the space; updating the gas concentration by accumulating the change amount to the gas concentration in the space before updating; A common known gas concentration in outside air is used as an initial value of the gas concentration before updating, Calculating the gas concentration using the current ventilation rate of the environmental device and the number of people in the space, and determining the next ventilation rate based on the gas concentration; Furthermore, the gas concentration is calculated using the next ventilation volume and the number of people in the space, and the next ventilation volume is determined based on the gas concentration. Control device.

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