Gas concentration estimation system, gas concentration estimation method, and controller
The gas concentration estimation system calculates gas concentration changes based on the number of people in a space, allowing for accurate estimation and ventilation control without a gas concentration sensor, thereby reducing power consumption.
Patent Information
- Application Number
- JP2023168596
- Authority / Receiving Office
- JP · JP
- Patent Type
- Applications
- Current Assignee / Owner
- Filing Date
- 2023-09-28
- Publication Date
- 2025-04-09
- Estimated Expiration
- 2043-09-28
AI Technical Summary
Conventional gas concentration estimation techniques require a gas concentration sensor, which is not always available, and struggle to accurately estimate gas concentrations without real-time sensor data.
A gas concentration estimation system that calculates the change in gas concentration per unit time using the number of people in a space, updates the gas concentration by accumulating these changes, and uses the outside air gas concentration as the initial value, allowing estimation without a gas concentration sensor.
Enables accurate estimation of gas concentrations even without a gas concentration sensor, allowing for appropriate ventilation control and reduced power consumption by adjusting ventilation amounts based on estimated concentrations.
Smart Images

Figure 2025058582000001_ABST
Abstract
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 ventilators that can ventilate are known. By ventilating, the gas concentration in a space can be made 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 the outside air. On the other hand, when an environmental equipment ventilates, an outside air load is generated, and more electricity is consumed than when no ventilation is performed.
[0003] There is known a technique for estimating an appropriate ventilation volume based on a CO2 concentration (see, for example, Patent Document 1). Patent Document 1 discloses a technique for estimating a 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, in conventional technology, a gas concentration sensor that detects the concentration of a gas such as CO2 is required to estimate the gas concentration.
[0006] The present disclosure provides a technique for estimating a gas concentration even without a gas concentration sensor. [Means for solving the problem]
[0007] A first aspect of the present disclosure is a method for manufacturing a semiconductor device comprising: A gas concentration estimation system that estimates a concentration of a predetermined gas in a space ventilated by an environmental device, comprising: 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 the update; 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 receives an input of a 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 amount of change in gas concentration per unit time using the number of people occupying 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 gap, the number of breaths per unit time, and the exhaled air 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 captured by a camera, by detecting people captured in an image of the space, by detecting people detected by a human presence 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 a current ventilation volume of the environmental device and the number of people in the space, and determines a 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 ventilation volume 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 the control unit calculates the gas concentration, an estimated value of the ventilation amount other than that ventilated by the environmental device is used.
[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 volume of draft air.
[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 air volume of the environmental device for a predetermined period of time assuming that the environmental device will continue to operate at a predetermined ventilation volume; Calculating the gas concentration based on a predetermined number of people model, and calculating a second air volume of the environmental device for a predetermined period when a ventilation volume 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 presented.
[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 outdoor 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 outdoor 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 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 as follows.
[0020] A thirteenth aspect of the present disclosure is a method for manufacturing a semiconductor device comprising: A gas concentration estimation method performed by a gas concentration estimation system that estimates a concentration of a predetermined gas in a space ventilated by an environmental device, comprising: The control unit calculates a 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 even without a gas concentration sensor.
[0022] A fourteenth aspect of the present disclosure is a method for producing a semiconductor device comprising: A control device that estimates a concentration of a predetermined gas in a space ventilated by an environmental device, Calculate 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.
[0023] According to the fourteenth aspect of the present disclosure, the gas concentration can be estimated even without a gas concentration sensor. Effect of the Invention
[0024] According to the present disclosure, the gas concentration can be estimated even without a gas concentration sensor. [Brief description of the drawings]
[0025] [Figure 1] FIG. 1 is a diagram for explaining an outline of a method for estimating a CO2 concentration. [Diagram 2] 1 is an example of a schematic perspective view of a main part of a gas concentration estimation system. [Diagram 3] FIG. 13 is a diagram showing another example of a schematic perspective view of a 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. [Diagram 5] FIG. 2 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 device by dividing the functions into blocks. [Figure 7] 4 is a diagram illustrating parameters stored in a parameter storage unit. FIG. [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 the space. [Figure 9] 11 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 a remote control device. [Figure 11] FIG. 13 is a diagram showing an example of a graph of various indexes when constant air volume ventilation control and ventilation control are performed using a CO2 concentration Pr. [Figure 12] 11 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. 11 is a flowchart illustrating 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 device by dividing the functions into blocks. [Figure 15] FIG. 13 is a diagram illustrating an example of a number-of-occupants model. [Figure 16] 11 is a flowchart illustrating an example of a process in which the information processing device presents a difference between a first air volume and a second air volume, and a difference between a first power consumption and a second power consumption. FIG. [Figure 17] 13A to 13C 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 a presentation unit. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[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 exist. For this reason, customers who purchase environmental equipment assume the number of people in the space, select the equipment according to this number, and adjust the ventilation volume by turning the equipment on and off. In other words, there is no control to finely adjust the ventilation volume according to 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 (if the maximum number of people in a room is estimated low, the actual CO2 concentration is likely to be high even if ventilation is performed). For this reason, customers ventilate with a ventilation volume that is greater than necessary for the actual number of people in the room. When ventilating, outside air flows into the space, but since the temperature and humidity of the outside air differ from the temperature and humidity 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 it is said to reach one-third of the power consumption of environmental equipment. Therefore, by adjusting the ventilation volume according to the actual number of people in the room, the outside air load caused by ventilation can be reduced, making it possible to reduce power consumption.
[0029] Since the actual number of people in a room correlates with air quality such as CO2 concentration, either the number of people in the room or the CO2 concentration is required to determine an appropriate ventilation amount. However, some environmental devices are not equipped with a CO2 sensor. Also, although it is costly to obtain an accurate number of people in a room, it is possible to estimate the number of people in a room approximately. Therefore, in this embodiment, a method for estimating the CO2 concentration based on the approximate number of people in a room without using a CO2 sensor will be described.
[0030] [First embodiment] <Outline of environmental equipment operation> With reference to FIG. 1, an outline of a method for estimating a CO2 concentration in this embodiment will be described. FIG. 1 is a diagram for explaining an outline of a method for estimating a CO2 concentration in this disclosure. The composition of air is nitrogen (about 78%), oxygen (about 21%), argon (about 0.93%), CO2 (about 0.03%), and others (about 0.04%). On the other hand, the breath exhaled by a person is nitrogen (about 78%), oxygen (15 to 16%), CO2 (4 to 5%), others, and trace gases generated in the body (about 1% including others). Therefore, CO2 and trace gases increase due to breathing. These are not included in the original air, so they can be said to be gases that increase due to breathing. Among gases, the change in CO2 concentration is extremely large at 4 to 5%. In this embodiment, an environmental device that suppresses an increase in CO2 concentration by controlling the ventilation volume according to the CO2 concentration will be described, taking CO2 as an example of one of the gases whose concentration changes due to exhalation. One of the features is that a CO2 sensor is not required to estimate the CO2 concentration.
[0031] First, the CO2 concentration in the space increases due to the increase in CO2 due to exhalation. When N people in a 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 space) x exhaled air 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 in 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 the space due to ventilation or drafts per unit time, B, is 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 by formula (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" indicates that the change in volume ΔPr is converted to 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 formula (4), the environmental device can estimate the CO2 concentration in the future unit time by accumulating the amount of change in the CO2 concentration in a unit time to the current CO2 concentration. In addition, 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 the CO2 concentration before the CO2 concentration exceeds a certain amount.
[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 to 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 formulas (1) and (2) by comparing the detected and estimated values of CO2 concentration.
[0033] <Terminology> The space is a space that has at least enough air for humans to survive, such as an indoor space. The specific space may be any of a variety of types, such as an office, a factory, a conference room, a seminar room, a living room, a movie theater, an exhibition room, etc.
[0034] Gas refers to the composition of air (gases that make up air). Gas may include not only inherent components of air such as oxygen, carbon dioxide, and nitrogen, but also substances contained in human 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 is used as an example of gas for explanation.
[0035] The unit time does not have to be a single unit of time such as 1 second, 1 minute, or 1 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 period, etc.
[0036] A manager is a person who has already introduced a gas concentration estimation system and who performs daily operation, regular inspections, repairs, etc. to maintain the functioning of the gas concentration estimation system. The manager may be the seller or user of the gas concentration estimation system. A person present is a person who is present in a space. A seller is a person in charge of the manufacturer or sales company that provides the gas concentration estimation system. A customer is a person who does not have a gas concentration estimation system but is considering introducing one.
[0037] Outside air refers to the part of the atmosphere surrounding the Earth that is close to the ground. Outside air may contain pollutants such as pollen, dust, and PM2.5. The gas concentration of the outside air is the concentration of the gas in this outside air.
[0038] <System configuration example> Fig. 2 is a schematic perspective view of an example of a main part 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. Although a sensor unit 8 is illustrated 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 the 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 the occupants 9 are present. 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 in the air flow path. In this embodiment, since the description will be given using CO2 as an example of a gas, the sensor may be a CO2 sensor. There are no particular limitations on the CO2 detection method of the CO2 sensor, but for example, the NDIR method (Non-Dispersive Infrared) is known.
[0040] The environmental equipment 10 may be an air conditioner or a ventilation device, but may be any equipment having a ventilation function. The environmental equipment 10 may have functions other than the ventilation function, for example, may have multiple functions such as a temperature control function and an air purifier. The environmental equipment 10 may only exhaust air and take in outside air by the negative pressure generated in the space 7, or may perform both exhaust and intake, or may only intake air. In addition, the ventilated air may or may not pass through a total heat exchanger. Multiple environmental equipment 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 also display the current CO2 concentration or the future CO2 concentration, and operate the environmental device 10 so as not to lower or increase the CO2 concentration. The user terminal 70 may be portable by the administrator. In addition, the user terminal 70 does not have to be installed in the same space 7 as the space 7 in which the sensor unit 8 is installed. In addition, the user terminal 70 may be used or viewed by general users (in this disclosure, the 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 general home, the manager may be a resident or a family member. General users are people who use the space 7, such as occupants 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 lower 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>> 3 shows another example of a schematic perspective view of the main parts 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, in the gas concentration estimation system 100, a plurality of communication networks (network NW1, network NW2) that function as transmission paths for signals between the indoor unit and the outdoor unit are constructed. 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 built into the air intake or the like. In this embodiment, since CO2 is used as an example of a gas, 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, similar to FIG. 2, the administrator can know the CO2 concentration in the space 7 displayed on the remote control device 15. In FIG. 3, instead of disposing the CO2 sensor 11 at 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 function of the information processing device 60. That is, when 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 process 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 described later in FIG. 4 may have the function of the information processing device 60.
[0050] <System configuration of gas concentration estimation system> 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 ventilators and a cloud-side information processing device 60 can communicate via a network N. The edge device 12, the environmental devices 10, the sensor switches 19, and the user terminal 70 are installed on the customer side, and the information processing device 60 is installed in a data center, the Internet, or other cloud. Note that the edge device 12 is a device that centrally manages the environmental devices 10 and the sensor switches 19, so the edge device 12 may not be necessary.
[0052] As described above, the environmental device 10 is preferably a device that comes into contact with the air in a space where people exist, such as an air conditioner, a ventilation device, etc. In general, the edge device 12 may be connected to security equipment, heat source equipment, a fire alarm, an AHU (air handling unit), a power 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 conform to the purposes of the environmental device 10 and the sensor switches 19. The contents of the control vary depending on the types of the environmental device 10 and the sensor switches 19, but for example, if the environmental device 10 is an air conditioner, it may include all controls related to the functions of the air conditioner, such as the cooling / heating mode, set temperature, ventilation volume, air volume, humidity, and wind direction that can generally be set in an air conditioner. For example, if the environmental device 10 is a ventilation device, it may include all controls related to the functions of the ventilation device, such as the ventilation volume. The sensor switches 19 may include a CO2 sensor 11.
[0054] The environmental device 10 collects operation 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 operation data varies depending on the environmental device 10, but in the case of an air conditioner, for example, the data may include high and low pressures of the refrigerant, the refrigerant temperature, the number of revolutions of the fan, 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 provided, 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, a plurality of information processing devices 60 with the same function may be prepared, and the plurality of 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 the status of the environmental device 10 and the sensor switches 19 from the edge device 12, and when a malfunction or the like occurs, takes measures to resolve the malfunction or dispatches a serviceman. 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 the user terminal 70, and obtains 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 a function of a Web server. In response to a request from a client software (Web client) such as a Web browser operated by a user, the Web server provides the client with screen information written in HTML files, XML, CSS files, JavaScript (registered trademark), etc. An application that uses the mechanisms of the Web in this way is called a Web application.
[0059] It is preferable that the information processing device 60 supports cloud computing, which is a form of usage 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), a wearable PC (sunglasses type, wristwatch type, etc.), etc. However, it is sufficient if the terminal has a communication function and can run a web browser or the like. Furthermore, the user terminal 70 may run a native app dedicated to the gas concentration estimation system 100 instead of a web browser.
[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 calculation devices such as a CPU (Central Processing Unit), etc. The processor 221 reads various programs onto the memory 222 and executes them. The processor 221 controls the information processing device 60 as a whole.
[0063] The memory 222 includes 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 a display device 230, which is an example of an external device, and an operation device 240 with the information processing device 60. 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 apparatus 225 is a communication device for communicating with the edge apparatus 12 and the user terminal 70 via the network N.
[0067] The drive device 226 is a device for setting the 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, a magneto-optical disk, etc. The recording medium 250 may also include semiconductor memories that record information electrically, such as ROM, flash memory, etc.
[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 in 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 illustrating the functions of the information processing device 60 by dividing them into blocks.
[0070] The information processing device 60 has a control unit 30 that estimates the CO2 concentration, controls the ventilation volume, and the like (an example of a control device). 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 built in the auxiliary storage device 223 or memory 222 in FIG. 5.
[0071] The CO2 concentration estimation unit 22 calculates the increase A in the volume of CO2 due to exhalation per unit time, the decrease B in the volume of CO2 due to ventilation and drafts of the environmental device 10 per unit time, the change ΔPr in the volume of CO2 in the space per unit time, and the CO2 concentration Pr after t seconds. Details will be described later.
[0072] The number of people detection unit 24 detects the number of people in a space required for estimating the CO2 concentration. For example, the following method for detecting the number of people may be adopted. If the space is a conference room, the time period and conference participants may be registered in the conference room's schedule system, so the number of participants detection unit 24 obtains the number of participants for each time period from the schedule 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. A camera installed at a door through which people enter and exit the space captures, 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 detects the number of people in the space by subtracting the number of people leaving the space from the number of people entering the space based on the head detection result. 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 image 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 provided 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 a free address system, if a person registers the desk he or she uses on the system, the number of people estimating unit 26 can obtain the number of people in the space 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 amount, and instructs the environmental device 10 to ventilate at the determined ventilation amount.
[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, if a CO2 sensor is not connected to the information processing device 60 but 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 present 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 a specified number of people or more are accommodated in the space.
[0076] When it is determined that the space contains a predetermined number of people or more, the warning output unit 27 outputs a warning to that effect to the manager. The predetermined number of people is, for example, the number of people for which it is difficult to control the concentration of gases such as CO2 so as not to 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. The parameters are stored in the parameter storage unit 29, which will be described later. The parameters to be corrected are the air volume of the gap, 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 (volume of the space, air volume of drafts), parameters related to people (time of day when people are present and number of people present, 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 in which people are present and which is the subject of ventilation. The unit of volume is "m 3 " The volume of the space is known, so it can be input in advance.
[0080] The volume of airflow through a gap is the volume of air flowing out of a space to the outside, or flowing into a space from the outside. The unit is, for example, "m 3 / 10 min". The exact value of the airflow rate of the gap is unknown, but it is possible to input an estimated value in advance based on the number of doors, etc. The airflow rate of the gap 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 time periods 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, etc. The units are, for example, "breathing times / 10 min" and "m 3 / 1 time and "%". The breathing conditions are fixed. The breathing rate and expiratory volume can be corrected as parameters of equation (5).
[0083] The rated ventilation air volume is the amount of air ventilated by the environmental device 10. The ventilation function allows for air volume adjustment (for example, extra strong, strong, and weak, but two-stage control or four-stage or more control is also possible). The unit is "m 3 / h” x the “number” of environmental devices 10. Since the rated ventilation 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." As an example, when the CO2 concentration Pr is over 900 [ppm], the environmental device 10 is controlled to operate at extra strong. When the CO2 concentration Pr is over 800 [ppm] and is equal to or less than 900 [ppm], the environmental device 10 is controlled to operate at strong. When the CO2 concentration Pr is equal to or less than 800 [ppm], 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 input in advance according to the season, but are just an example. The indoor temperature and humidity may 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 may be values detected by the outdoor unit's sensor. As 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 input in advance because 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 the COP is known as the specification of the environmental device 10, it is pre-input.
[0088] <Estimation of CO2 Concentration When Not Using a CO2 Sensor> 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 in 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 in Equation 321. The second term in 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 further expanding the first term in Equation 321 and the second term in Equation 322, 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 the 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 in Equation (5) is the increase amount A of CO2 due to exhalation shown in Equation (1). The second term in 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 on unit time. Equation (5) assumes 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 of a large error. Therefore, the unit time is preferably set to the minimum time that allows for a certain change amount of the CO2 concentration Pr and during which 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 when 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, with reference 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 or is of the same order as the outside air. 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 Pr value.
[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 reduction in the CO2 volume due to ventilation of the environmental equipment per unit time + the amount of reduction in the CO2 volume due to drafts per unit time B" (S13). The amount of reduction B is calculated by formula (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 the formula (3).
[0096] Next, the CO2 concentration estimation unit 22 calculates the change amount C (C=ΔPr / V) of the CO2 concentration Pr from the change amount 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 the formula (4).
[0098] Next, the device control unit 23 compares for each threshold whether or not the CO2 concentration Pr after t seconds has exceeded the threshold (the control condition in FIG. 7) (S17).
[0099] The device control unit 23 controls the ventilation amount of the environmental device 10 according to the threshold value exceeded by the CO2 concentration Pr after t seconds (S18). For example, according to the parameter storage unit 29, the device control unit 23 controls the ventilation amount to be extra strong when the CO2 concentration Pr is over 900 [ppm], controls the ventilation amount to be strong when the CO2 concentration Pr is over 800 [ppm] and less than 900 [ppm], and controls the ventilation amount 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 ahead, making it possible to perform feedforward control by 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 the threshold, so there is a risk that there will be a time when the CO2 concentration Pr exceeds the threshold.
[0101] In step S16, the CO2 concentration Pr is estimated based on the current ventilation volume, and in step S18, the next ventilation volume is determined based on this CO2 concentration Pr. Furthermore, when the process of FIG. 9 is executed next time, the CO2 concentration Pr is estimated based on the next ventilation volume, and in step S18, the ventilation volume after the next one is determined based on this CO2 concentration Pr. In this way, the control of the ventilation volume and the estimation of the CO2 concentration Pr are repeated, so that the ventilation volume is appropriately determined and the accuracy of the CO2 concentration Pr can be maintained.
[0102] Moreover, it is preferable that the information processing device 60 repeats the process of FIG. 9 for 24 hours. As shown in step S11 of FIG. 9, the CO2 concentration of the outside air is used as the initial value of the CO2 concentration Pr. In an office where daytime shifts are normal, even if the environmental device 10 is OFF, the CO2 concentration Pr of the space in the morning drops to the CO2 concentration of the outside air. However, the CO2 concentration may not drop completely by the time employees arrive at work in the morning. For example, in a space where people may be present until midnight or dawn, the CO2 concentration does not drop completely by the time employees arrive at work. In this case, by setting the CO2 concentration of the outside air as the initial value, an initial value different from the actual CO2 concentration Pr of the space is set, and the CO2 concentration Pr estimated by the process of FIG. 9 may also differ from the actual CO2 concentration. Therefore, by the information processing device 60 repeating the process of FIG. 9 for 24 hours, it is possible to suppress the deviation between the actual CO2 concentration and the estimated CO2 concentration Pr caused by the setting of the initial value.
[0103] In addition, even if the information processing device 60 continues to estimate the CO2 concentration for 24 hours, the ventilation function may be turned off during the time period 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 CO2 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 the 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 setting the set temperature, operation mode, set air volume, set air direction, and operation schedule, initial settings set at the time of installation or maintenance, setting of the display mode on the display unit 51, and the like.
[0106] The remote control device 15 has a display unit 51. On the display unit 51, an installation location 52, a current information display field 53, a message display field 54, a setting button 55, etc. are displayed. On the current information display field 53, a current air volume 53a, an air direction 53b, a set temperature 53c, an outside air temperature 53d, a CO2 concentration Pr, and a room temperature 53f are displayed. The CO2 concentration Pr is the CO2 concentration after a unit time has elapsed calculated by the information processing device 60, but the CO2 concentration before the unit time has elapsed (one cycle before the process of FIG. 9) may be displayed. 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 the past CO2 concentration Pr in a chronological order as a graph or numerical values. The display unit 51 may display the number of people in the space used in the calculation or estimated. When 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 display it. The user terminal 70 is connected to the information processing device 60 and can display the CO2 concentration Pr and past history of each space using a Web application or the like. The information processing device 60 may also send the CO2 concentration Pr by email to the email address of the administrator, or may display the CO2 concentration on a display arranged in the space. <Effect of ventilation control using CO2 concentration Pr in this embodiment> FIG. 11 shows graphs of various indices when constant air volume ventilation control and ventilation control are performed using the CO2 concentration Pr. Constant air volume ventilation control is an existing ventilation method that ventilates at a constant ventilation volume regardless of the CO2 concentration. Ventilation control using the CO2 concentration Pr is the ventilation control of this embodiment, and is a ventilation method that controls the ventilation volume according to the CO2 concentration Pr estimated without using a CO2 sensor.
[0109] FIG. 11 shows 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 occupying 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 air volume (ventilation control using CO2 concentration Pr) 304 increases and decreases according to the number of people in the room. Also, the CO2 concentration (constant air volume ventilation control) 301 increases when the number of people in the room increases and decreases when the number of people in the room decreases, so the CO2 concentration is prone to fluctuation. On the other hand, the CO2 concentration (ventilation control using CO2 concentration Pr) 302 is maintained at approximately 800 [ppm] regardless of the number of people in the room, and it can be seen that a CO2 concentration that is sufficiently low compared to a specified value such as 1000 [ppm] can be maintained.
[0111] Also, comparing air volume (constant air volume ventilation control) 303 and air volume (ventilation control using CO2 concentration Pr) 304, it is found 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 the present 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 305 in the room decreases toward the end of regular working hours (time t3), both the CO2 concentration (constant air volume ventilation control) 301 and the CO2 concentration (ventilation control using CO2 concentration Pr) 302 gradually decrease. The reason why the CO2 concentration (constant air volume ventilation control) 301 and the CO2 concentration (ventilation control using CO2 concentration Pr) 302 continue to decrease even after the time t3 when ventilation ends is because there is ventilation due to drafts. In addition, there is a concentration difference 306 between the CO2 concentrations at time t4 and time t1, but 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] <Calculation of 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 manager inputs the CO2 concentration Mv detected by the CO2 sensor to the information processing device 60. The three equations for calculating the CO2 concentration Pr are shown again. A = (CO2 concentration in exhaled air - CO2 concentration in space) x exhaled air 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 is no particular restriction on the timing when the administrator inputs 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, so the number of people estimation unit 26 can calculate the number of people H from equations (1) and (2).
[0115] Fig. 12 is a flow chart for explaining the process in 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 to the information processing device 60. The process in Fig. 12 may be performed before or 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 formula (6) calculates the "amount of change in CO2 concentration per unit time," the administrator inputs the CO2 concentration 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 change in the CO2 concentration Mv in step S22 by the space volume V to calculate the 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 judges whether the estimated number of people H in the room exceeds a specified number of people (S25). The specified number of people is, for example, a capacity or the like that is 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 of people (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 on a display arranged in the space. In this way, the information processing device 60 can maintain the number of people in the space 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 formulas (1) to (4), the air volume of the air gap, the respiratory rate, and the CO2 concentration of the exhaled air are used to estimate the CO2 concentration Pr. Therefore, if the estimated CO2 concentration Pr is significantly different 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 flow chart illustrating the process of correcting parameters by the parameter correction unit 21. The process of Fig. 13 is performed when the CO2 concentration receiving unit 25 receives the CO2 concentration Mv.
[0124] First, the parameter correction unit 21 acquires the CO2 concentration Mv received by the CO2 concentration receiving unit 25 and the most recently estimated CO2 concentration Pr (S31).
[0125] The parameter correction unit 21 determines whether the difference between the CO2 concentration Mv and the CO2 concentration Pr (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 implements one or more of the following: increasing the air volume of the gap, reducing the number of breaths, or reducing the volume of exhaled air (S33).
[0127] If the determination in step S32 is No, the parameter correction unit 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 amount of airflow through the gap, increasing the number of breaths, or increasing the volume of exhaled air (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 the information processing device 60 can estimate the CO2 concentration Pr with high accuracy even if a CO2 sensor is not connected to the information processing device 60.
[0130] It may be determined in advance which parameter to correct among the air volume of the gap, the respiratory rate, or the exhaled air volume, which are the parameters to be corrected. For example, the parameter correction unit 21 switches between the air volume of the gap, the respiratory rate, or the exhaled air volume in order and corrects one of them every time the process of FIG. 13 is executed. That is, the parameter correction unit 21 corrects the air volume of the gap the first time, corrects the respiratory rate the second time, and corrects the exhaled air volume the third time. The parameter correction unit 21 returns to the air volume of the gap the fourth time. Alternatively, the parameter correction unit 21 may correct all of the air volume of the gap, the respiratory rate, or the exhaled air volume little by little (one third of the amount of correction of one parameter in one correction) in one 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 unit time future by accumulating the change amount ΔPr of the CO2 concentration Pr in a unit time to the current CO2 concentration Pr. In addition, since the environmental device 10 can predict the CO2 concentration Pr in t seconds, 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 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 to 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 formulas (1) and (2) by comparing the detected and estimated values of CO2 concentration.
[0133] [Second embodiment] In the first embodiment, the information processing device 60 that estimates the CO2 concentration Pr and controls the ventilation volume is described. In the present embodiment, the information processing device 60 that estimates the CO2 concentration Pr and presents the annual ventilation volume and power consumption reduced by controlling the ventilation volume is 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). The air volume calculation unit 31 also 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-occupants model (see FIG. 15) described later, 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). Since 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 the 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 of a customer. The occupancy number model is created by the seller from 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 in the past, the information processing device 60 may use this to create the occupancy number model. The information processing device 60 may, for example, obtain the number of occupants per time period by day of the week from the past records and use the average by day of the week and time period as the occupancy number model.
[0139] The occupancy model is a table having the number of occupants for each time period. In Fig. 15, this table is shown in the form of a bar graph. Although Fig. 15 shows the number of occupants for each hour in the graph, it is preferable to convert the number of occupants for each unit time into data. Even for customers who have not introduced the gas concentration estimation system 100, the number of occupants 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> Fig. 16 is a flow chart for explaining 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 the device continues 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, half a year, etc. The predetermined ventilation volume may be an air volume roughly calculated based on the maximum number of people that may exist 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 ]x 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). In this calculation, the outdoor air load [W] is taken into consideration. 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 x 0.33 x indoor / outdoor specific enthalpy difference x (1 - heat exchange rate)...(7) Power consumption = (outdoor air load / air conditioner COP)...(8) Formula (7) shows the case where the ventilated air passes through a total heat exchanger. When the ventilated air does not pass through a total heat exchanger, formula (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 bill = Power consumption x Unit price of electricity ……(9) Fig. 17 shows the difference 311 between the first air volume and the second air volume, the difference 312 between the first power consumption and the second power consumption, and the difference 313 between the first electricity charge and the second electricity charge presented by the presentation unit 33. The screen of Fig. 17 can be displayed on the user terminal 70 used by, for example, a seller or a customer. As shown in Fig. 17, air volumes 314, 315, power consumption 316, 317, and electricity charges 318, 319 are presented for each of the cases of constant air volume and CO2 concentration ventilation control. In addition, the difference 311 in air volume, the difference 312 in power consumption, and the difference 313 in electricity charge are displayed for each of the cases of constant air volume and CO2 concentration ventilation control.
[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 approval processes 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 is not 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 of power consumption, etc.
[0147] <Other application examples> The above describes the best mode for carrying out the present disclosure 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 included. 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 H in the room.
[0149] Furthermore, the unit time does not have to be fixed at 10 minutes, but may be changed depending on the time period. For example, the unit time can be shortened during times when there is a lot of people coming and going, and lengthened during times when there is little. By shortening the unit time during times 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] Moreover, the configuration example in FIG. 6 and the like is divided according to main functions in order 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 be divided into more processing units according to the processing contents. Also, it can be divided so that one processing unit includes more processes.
[0151] Moreover, the devices described in the examples are merely one of a number of computing environments for implementing the embodiments disclosed herein. In one embodiment, the information processing device 60 includes a number of computing devices, such as a server cluster. The computing devices are configured to communicate with each other via any type of communication link, including a network, shared memory, and the like, and perform the processes disclosed herein.
[0152] Each function of the present disclosure described above can be realized not only by software processing by executing a program, but also by one or more processing circuits. Here, the "processing circuit" in this specification includes a processor programmed to execute each function by software, such as a processor implemented by an electronic circuit, an ASIC (Application Specific Integrated Circuit), a DSP (Digital Signal Processor), an FPGA (Field Programmable Gate Array), and a device such as a conventional circuit module designed to execute each function 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 for this initial value, "the amount of change in gas concentration per unit time is calculated using the number of people occupying the space", and "the amount of change is accumulated to the gas concentration in the space before the update to update the gas concentration", so that the gas concentration is estimated for each unit time when the number of people occupying is not expected to change, and these are 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 occupying the space," so that the parameters of the model equation can be corrected with the input gas concentration, and appropriate parameters can be set for the space even without a gas concentration sensor, making it possible to estimate the gas concentration with high accuracy.
[0156] In a fourth aspect of the present disclosure, "the parameters of the model formula are the air volume of the draft, the respiratory rate 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 the draft, the respiratory rate 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 by using a camera, a sensor, a schedule system, manual input, etc., and therefore can obtain an accurate number of people present in a room and estimate a gas concentration with high accuracy.
[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 enabling estimation of the gas concentration to continue for 24 hours even in spaces where people are present at night. Therefore, 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, it is possible to estimate the gas concentration with high accuracy.
[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 ventilation volume other than that when an environmental device ventilates," and therefore can estimate gas concentrations with high accuracy even when the environmental device ventilates naturally other than 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 (lots of drafts).
[0162] The tenth aspect of the present disclosure "calculates a first airflow rate of the environmental device for a specified period of time when it is assumed that the device will continue to operate at a specified ventilation rate, calculates the gas concentration based on a specified model of the number of people present, calculates a second airflow rate of the environmental device for a specified period of time when the ventilation rate is adjusted according to the calculated gas concentration, and calculates a first power consumption consumed at the first airflow rate and a second power consumption consumed at the second airflow rate," 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 a more accurate power consumption can be calculated taking the outdoor air load into account.
[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 a concentration of a predetermined gas in a space ventilated by an environmental device, comprising: 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 the update; A gas concentration estimation system that uses the gas concentration of outside air as the initial value of the gas concentration before updating.
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 in the space, 3. The gas concentration estimation system according to claim 1, wherein when there is a difference between the updated gas concentration and the input gas concentration that is equal to or greater than a threshold value, a parameter of a model formula that calculates the amount of change in gas concentration per unit time using the number of people occupying the space is corrected.
4. The parameters of the model formula are the air volume of the gap, the number of breaths per unit time, and the exhaled air 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. The gas concentration estimation system of claim 1, wherein the control unit acquires the number of people present by detection results of people entering and exiting the space photographed by a camera, detection results of people appearing in an image photographed of the space, detection results of people detected by a human presence sensor provided on the seat, people using the space acquired from a schedule system, or manual input of 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 control unit calculates the gas concentration using a current ventilation volume of the environmental device and the number of people in the space, and determines a next ventilation volume based on the gas concentration. The gas concentration estimation system according to claim 1 , further comprising: calculating the gas concentration using the next ventilation rate and the number of people in the space; and determining the ventilation rate for the next ventilation rate based on the gas concentration.
8. The gas concentration estimation system according to claim 1 , wherein the control unit uses an estimated value of a ventilation amount other than that provided by the environmental device when calculating the gas concentration.
9. The gas concentration estimation system according to claim 8 , wherein the estimated ventilation volume is a volume of airflow through a gap.
10. the control unit calculates a first air volume of the environmental device for a predetermined period of time assuming that the environmental device will continue to operate at a predetermined ventilation volume; Calculating the gas concentration based on a predetermined number of people model, and calculating a second air volume of the environmental device for a predetermined period when a ventilation volume 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 air volume and the second air volume, or a difference between the first power consumption and the second power consumption.
11. The gas concentration estimation system according to claim 10 , 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.
12. the predetermined gas is CO2, The control unit calculates the increase A in CO2 volume due to breathing as 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 reduction in CO2 volume due to ventilation and drafts is B. 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:
13. A gas concentration estimation method performed by a gas concentration estimation system that estimates a concentration of a predetermined gas in a space ventilated by an environmental device, comprising: The control unit calculates a 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 gas concentration estimation method, comprising: using an outside air gas concentration as an initial value of the gas concentration before updating.
14. A control device that estimates a concentration of a predetermined gas in a space ventilated by an environmental device, Calculate 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 control device that uses the gas concentration of the outside air as the initial value of the gas concentration before updating.
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