JP2014228518A - Carbon dioxide concentration measuring system, and calibration method of carbon dioxide sensor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an accurate carbon dioxide concentration measuring system.SOLUTION: The carbon dioxide concentration measuring system includes: an air-supply duct 2 for supplying air to chambers 1A, 1B, and 1C; carbon dioxide sensors 10A, 10B, and 10C for chambers disposed in the chambers 1A, 1B, and 1C; a carbon dioxide sensor 20 for calibration disposed in the air-supply duct 2 outside the chambers 1A, 1B, and 1C; and a controller 300 for calibrating the carbon dioxide sensors 10A, 10B, and 10C for chambers on the basis of the carbon dioxide concentration measured by the carbon dioxide sensor 20 for calibration.

Description

  The present invention relates to an environmental evaluation technique, and more particularly to a carbon dioxide concentration measurement system and a carbon dioxide sensor calibration method.

  For example, in Japan, the carbon dioxide concentration in the living space of people in buildings is supposed to be 1000 ppm or less. Therefore, there is an example in which a carbon dioxide sensor is provided in the room and the carbon dioxide concentration inside the room is monitored. When the carbon dioxide concentration inside the room rises, outside air is introduced into the room and the carbon dioxide concentration inside the room is lowered. Note that the carbon dioxide concentration in the outside air is 400 ppm.

  When no one is present in the living space, the carbon dioxide concentration in the living space is close to the carbon dioxide concentration in the outside air. Therefore, an ABC (Automatic Baseline Calibration) method has been proposed as an automatic calibration method for a carbon dioxide sensor. According to the ABC method, the measured value of the carbon dioxide concentration by the carbon dioxide sensor is monitored, for example, for 24 hours, and the carbon dioxide sensor is calibrated based on the deviation of the measured value of the carbon dioxide concentration from the lowest value of 400 ppm (for example, , See Patent Document 1).

JP-A-11-14583

  However, due to exhaust from automobiles and factories, the carbon dioxide concentration in the outside air does not necessarily become 400 ppm, and may be higher. Therefore, even if the carbon dioxide sensor is calibrated uniformly based on 400 ppm, the measured value by the carbon dioxide sensor cannot be accurate. Accordingly, an object of the present invention is to provide an accurate carbon dioxide concentration measurement system and a carbon dioxide sensor calibration method.

  According to an aspect of the present invention, (a) an air supply duct for supplying air to a room, (b) a room carbon dioxide sensor disposed in the room, and (c) an air supply outside the room There is provided a carbon dioxide concentration measuring system comprising: a calibration carbon dioxide sensor provided in a duct; and (d) a controller that calibrates the room carbon dioxide sensor based on the carbon dioxide concentration measured by the calibration carbon dioxide sensor. The

  Moreover, according to the aspect of the present invention, (a) supplying air to the room via the air supply duct, and (b) measuring the carbon dioxide concentration with the room carbon dioxide sensor disposed in the room. And (c) measuring the carbon dioxide concentration with a calibration carbon dioxide sensor provided in the air supply duct outside the room, and (d) based on the carbon dioxide concentration measured by the calibration carbon dioxide sensor, A method for calibrating a carbon dioxide sensor is provided.

  According to the present invention, an accurate carbon dioxide concentration measurement system and a carbon dioxide sensor calibration method can be provided.

1 is a schematic diagram of a carbon dioxide concentration measurement system according to an embodiment of the present invention. It is a schematic diagram of the carbon dioxide concentration measuring system which concerns on other embodiment of this invention.

  Embodiments of the present invention will be described below. In the following description of the drawings, the same or similar parts are denoted by the same or similar reference numerals. However, the drawings are schematic. Therefore, specific dimensions and the like should be determined in light of the following description. Moreover, it is a matter of course that portions having different dimensional relationships and ratios are included between the drawings.

  As shown in FIG. 1, the carbon dioxide concentration measurement system according to the embodiment includes an air supply duct 2 for supplying air to each of a plurality of rooms 1A, 1B, 1C, and a plurality of rooms 1A, 1B, A plurality of room carbon dioxide sensors 10A, 10B, and 10C respectively disposed in 1C; a calibration carbon dioxide sensor 20 provided in the air supply duct 2 outside the plurality of rooms 1A, 1B, and 1C; And a controller 300 that calibrates the plurality of room carbon dioxide sensors 10A, 10B, and 10C based on the carbon dioxide concentration measured by the carbon sensor 20.

  The plurality of rooms 1A, 1B, and 1C are included in, for example, a building, a condominium, and a detached house. At least a part of the air supply duct 2 is disposed on the ceiling 30, for example. The carbon dioxide concentration measurement system according to the embodiment forms part of an air conditioning system, for example, and the air supply duct 2 is connected to an air conditioner 40 including a fan such as a fan or a pump. The air conditioner 40 is arrange | positioned at the air-conditioning machine room 31, for example. The controller 300 is electrically connected to the air conditioner 40 as a part of the air conditioning system, and controls the air conditioner 40.

  In each of the plurality of rooms 1A, 1B, 1C, a plurality of temperature / humidity sensors 15A, 15B, 15C are arranged. The plurality of temperature / humidity sensors 15A, 15B, 15C measure the temperature / humidity of the plurality of rooms 1A, 1B, 1C, respectively, and transmit the measured values to the controller 300. The air conditioner 40 blows air through the air supply duct 2 to the plurality of rooms 1A, 1B, 1C. For example, the controller 300 controls the air conditioner 40 so as to send out air whose temperature and humidity are adjusted to the air supply duct 2 based on the measurement values of the temperature / humidity sensors 15A, 15B, and 15C. The controller 300 also controls the air volume of the air sent from the air conditioner 40 to the air supply duct 2.

  A part of the air sent out to the air supply duct 2 is discharged into the room 1 </ b> A through the air supply duct 3 </ b> A connected to the air supply duct 2. A part of the air sent out to the air supply duct 2 is discharged into the room 1B through the air supply duct 3B connected to the air supply duct 2. Further, a part of the air sent out to the air supply duct 2 is discharged into the room 1 </ b> C through the air supply duct 3 </ b> C connected to the air supply duct 2.

  The air in the room 1A is sucked into the air conditioner 40 via the return air ducts 4A, 5 and 6. The air in the room 1B is sucked into the air conditioner 40 through the return air ducts 4B, 5 and 6. The air in the room 1C is sucked into the air conditioner 40 through the return air ducts 4C, 5 and 6. The air conditioner 40 adjusts the temperature and humidity of the sucked air again and sends it out to the air supply duct 2. Thereby, air with the same temperature and humidity is supplied to the plurality of rooms 1A, 1B, and 1C.

  The room carbon dioxide sensor 10A measures the carbon dioxide concentration in the room 1A. The room carbon dioxide sensor 10B measures the carbon dioxide concentration in the room 1B. The room carbon dioxide sensor 10C measures the carbon dioxide concentration in the room 1C. The plurality of room carbon dioxide sensors 10A, 10B, and 10C are electrically connected to the controller 300. A controller 300 including a central processing unit (CPU), a storage device, and the like receives respective measured values of carbon dioxide concentration from a plurality of room carbon dioxide sensors 10A, 10B, and 10C.

  Each of the plurality of room-use carbon dioxide sensors 10A, 10B, and 10C measures the carbon dioxide concentration by, for example, a non-dispersive infrared absorption method (NDIR: Non-dispersive Infrared Absorbent method). That is, each of the plurality of room carbon dioxide sensors 10A, 10B, and 10C uses the characteristic that carbon dioxide absorbs infrared rays, and measures the attenuation amount of infrared rays caused by being absorbed by carbon dioxide. Measure the concentration. Therefore, each of the plurality of room carbon dioxide sensors 10A, 10B, and 10C includes, for example, an infrared lamp and an optical system including a reflecting mirror.

  An outside air introduction duct 8 is further connected to the air conditioner 40. The open end of the outside air introduction duct 8 is in contact with outdoor air. In addition to the return air duct 6, an exhaust duct 9 is connected to the return air duct 5 through which air sucked from the plurality of rooms 1 </ b> A, 1 </ b> B, 1 </ b> C flows. The open end of the exhaust duct 9 is in contact with outdoor air.

  The return air duct 6 is provided with a circulating air flow adjusting mechanism 61. The outside air introduction duct 8 is provided with an introduction air flow adjusting mechanism 81. The exhaust duct 9 is provided with a discharge airflow adjusting mechanism 91. A valve, a damper, or the like can be used for each of the circulating airflow adjustment mechanism 61, the introduction airflow adjustment mechanism 81, and the exhaust airflow adjustment mechanism 91. The circulation airflow adjustment mechanism 61, the introduction airflow adjustment mechanism 81, and the discharge airflow adjustment mechanism 91 are electrically connected to the controller 300, for example. The controller 300 controls the opening and closing of the circulating airflow adjustment mechanism 61, the introduction airflow adjustment mechanism 81, and the exhaust airflow adjustment mechanism 91.

  When air is circulated through the plurality of rooms 1A, 1B, and 1C, the controller 300 opens the circulating airflow adjustment mechanism 61 and closes the introduction airflow adjustment mechanism 81 and the discharge airflow adjustment mechanism 91. Thereby, the approach of the outside air to the plurality of rooms 1A, 1B, 1C is blocked or suppressed, and heat exchange with the outdoors is suppressed. The controller 300 monitors the carbon dioxide concentration measured by each of the plurality of room carbon dioxide sensors 10A, 10B, and 10C, and the carbon dioxide measured by any of the plurality of room carbon dioxide sensors 10A, 10B, and 10C. When the concentration is equal to or higher than the threshold value, the circulating air flow adjustment mechanism 61 is closed, and the introduction air flow adjustment mechanism 81 and the exhaust air flow adjustment mechanism 91 are opened. Thereby, outside air is introduced into the plurality of rooms 1A, 1B, and 1C, and the air inside the plurality of rooms 1A, 1B, and 1C is discharged to the outdoors. Therefore, it becomes possible to reduce the carbon dioxide concentration inside the plurality of rooms 1A, 1B, 1C.

  Here, in each of the plurality of room carbon dioxide sensors 10A, 10B, and 10C, the optical system including the infrared lamp and the reflecting mirror may deteriorate over time. Therefore, it is preferable that each of the plurality of room carbon dioxide sensors 10A, 10B, and 10C is periodically calibrated. However, it is preferable to have the proofreader regularly enter each of the plurality of rooms 1A, 1B, and 1C from the viewpoint of the privacy and confidentiality management of each of the plurality of rooms 1A, 1B, and 1C. There may not be. Moreover, it may not be preferable from a viewpoint of cost that the calibration person calibrates each of the plurality of room carbon dioxide sensors 10A, 10B, and 10C.

  On the other hand, in the carbon dioxide concentration measurement system according to the embodiment, the calibration carbon dioxide sensor 20 is provided in the air supply duct 2 in the air conditioning machine room 31 outside the plurality of rooms 1A, 1B, and 1C. . The configuration of the calibration carbon dioxide sensor 20 is, for example, the same as each of the plurality of room carbon dioxide sensors 10A, 10B, and 10C, and the carbon dioxide concentration is measured by a non-dispersive infrared absorption method. In the air conditioning machine room 31, there is little need to consider the privacy and confidentiality management of the owner and lessee. For this reason, it is possible to cause the calibration person to enter the air-conditioning machine room 31 at regular intervals and to calibrate the calibration carbon dioxide sensor 20.

  When calibrating each of the plurality of room carbon dioxide sensors 10A, 10B, and 10C, for example, a controller including a timer in a predetermined time zone in which a plurality of rooms 1A, 1B, and 1C are absent, such as midnight 300 recognizes. Alternatively, the controller 300 may recognize the time zone in which the carbon dioxide concentrations in the plurality of rooms 1A, 1B, and 1C are lowest on the previous day. Alternatively, the measured values of the carbon dioxide concentrations in the rooms 1A, 1B, and 1C are monitored in time series via the room carbon dioxide sensors 10A, 10B, and 10C. The controller 300 may recognize that no person is present in the plurality of rooms 1A, 1B, and 1C when the threshold value that can be considered to be lower is below a certain time.

  Next, the controller 300 opens the circulating airflow adjustment mechanism 61 and closes the introduction airflow adjustment mechanism 81 and the exhaust airflow adjustment mechanism 91. Further, the air conditioner 40 circulates air to the plurality of rooms 1A, 1B, 1C. At this time, by increasing the blowing speed of the air conditioner 40 to the maximum, the carbon dioxide concentrations of the air in the plurality of rooms 1A, 1B, 1C can be made uniform in a short time.

  After that, the controller 300 waits for the time that the carbon dioxide concentration of the air flowing through the air supply duct 2 and the air in the plurality of rooms 1A, 1B, 1C is expected to become uniform elapses, for example. The said time is computable from the air volume of the air which flows through the air supply duct 2, and the volume of several room 1A, 1B, 1C etc., for example. Alternatively, the controller 300 may wait for the measured values of the plurality of room carbon dioxide sensors 10A, 10B, and 10C to be constant.

  Next, the controller 300 includes a plurality of carbon dioxide concentrations so that there is no difference between the carbon dioxide concentration measured by the calibration carbon dioxide sensor 20 and the carbon dioxide concentrations measured by the plurality of room carbon dioxide sensors 10A, 10B, and 10C. The room carbon dioxide sensors 10A, 10B, and 10C are calibrated. For example, the controller 300 calculates the difference between the measured value of the carbon dioxide concentration of the room carbon dioxide sensor 10A and the measured value of the carbon dioxide concentration of the calibration carbon dioxide sensor 20, and then the The calculated difference is subtracted from the measured value of the carbon dioxide concentration to correct the measured value of the carbon dioxide concentration of the room carbon dioxide sensor 10A.

  After the calibration of the plurality of room carbon dioxide sensors 10A, 10B, and 10C is completed, the air conditioner 40 resumes operation in a normal state, and the controller 300 includes a plurality of room carbon dioxide sensors 10A, 10B, Monitor each 10C corrected carbon dioxide concentration measurement.

  If the plurality of room carbon dioxide sensors 10A, 10B, and 10C are calibrated by the method described above, it is not necessary for the person in charge of calibration to enter each of the plurality of rooms 1A, 1B, and 1C. Therefore, it becomes possible to protect the privacy and confidentiality management of the owners and renters of the plurality of rooms 1A, 1B, and 1C. In addition, since the calibration person only has to calibrate only one calibration carbon dioxide sensor 20, it is possible to reduce the cost for calibration.

(Other embodiments)
Although the present invention has been described by the embodiments as described above, it should not be understood that the description and drawings constituting a part of this disclosure limit the present invention. From this disclosure, various alternative embodiments, examples and operational techniques should be apparent to those skilled in the art. For example, a human detection sensor may be arranged in each of the plurality of rooms 1A, 1B, 1C. In this case, the controller 300 starts calibration of the plurality of room carbon dioxide sensors 10A, 10B, and 10C when the plurality of person detection sensors do not detect a person in each of the plurality of rooms 1A, 1B, and 1C. May be. The air conditioner 40 and the calibration carbon dioxide sensor 20 may be disposed outdoors. Alternatively, the calibration carbon dioxide sensor 20 may be disposed on the ceiling 30 of the rooms 1A, 1B, 1C as shown in FIG. Further, the controller 300 may monitor and manage all of carbon dioxide, temperature, humidity, and human detection sensor, or may monitor and manage only the carbon dioxide sensor.

  The present invention can also be applied to a case where a plurality of air supply ducts are arranged in one room and a plurality of room carbon dioxide sensors are provided in the one room. Thus, it should be understood that the present invention includes various embodiments and the like not described herein.

1A, 1B, 1C Room 2, 3A, 3B, 3C Air supply ducts 4A, 4B, 4C, 5, 6 Return air duct 8 Outside air introduction duct 9 Exhaust ducts 10A, 10B, 10C Room carbon dioxide sensors 15A, 15B, 15C Temperature / humidity sensor 20 Carbon dioxide sensor for calibration 30 Back of ceiling 31 Air conditioning machine room 40 Air conditioner 61 Circulating air flow adjusting mechanism 81 Introducing air flow adjusting mechanism 91 Discharged air flow adjusting mechanism 300 Controller

Claims (18)

An air supply duct for supplying air to the room;
A carbon dioxide sensor for a room disposed in the room;
A calibration carbon dioxide sensor provided in the air supply duct outside the room;
A controller for calibrating the room carbon dioxide sensor based on the carbon dioxide concentration measured by the calibration carbon dioxide sensor;
A carbon dioxide concentration measuring system.   The controller calibrates the room carbon dioxide sensor so that there is no difference between the carbon dioxide concentration measured by the calibration carbon dioxide sensor and the carbon dioxide concentration measured by the room carbon dioxide sensor. 2. The carbon dioxide concentration measuring system according to 1. A human detection sensor disposed in the room;
3. When the person detection sensor does not detect a person in the room, the controller calibrates the room carbon dioxide sensor based on the carbon dioxide concentration measured by the calibration carbon dioxide sensor. The carbon dioxide concentration measurement system described in 1.   The carbon dioxide concentration measuring system according to claim 1 or 2, wherein the controller includes a timer and calibrates the room carbon dioxide sensor based on the carbon dioxide concentration measured by the calibration carbon dioxide sensor at a predetermined time. .   The carbon dioxide concentration measuring system according to any one of claims 1 to 4, further comprising a blower for blowing air into the room through the air supply duct.   The carbon dioxide concentration measurement system according to claim 5, wherein the blower is included in an air conditioner, and the air conditioner and the calibration carbon dioxide sensor are arranged in an air conditioning machine room.   The carbon dioxide concentration measurement system according to any one of claims 1 to 5, wherein the calibration carbon dioxide sensor is disposed in an attic of the room.   The carbon dioxide concentration measurement system according to claim 1, wherein when calibrating the room carbon dioxide sensor, the entry of outside air into the room is blocked or suppressed.   The carbon dioxide concentration measurement system according to claim 1, wherein the calibration carbon dioxide sensor is calibrated at an arbitrary time. Supplying air to the room via the air supply duct;
Measuring the carbon dioxide concentration with a room carbon dioxide sensor located in the room;
Outside the room, measuring the carbon dioxide concentration with a calibration carbon dioxide sensor provided in the air supply duct;
Calibrating the room carbon dioxide sensor based on the carbon dioxide concentration measured by the calibration carbon dioxide sensor;
A method for calibrating a carbon dioxide sensor, comprising:   The said carbon dioxide sensor for rooms is calibrated so that the difference between the carbon dioxide concentration measured by the calibration carbon dioxide sensor and the carbon dioxide concentration measured by the room carbon dioxide sensor is eliminated. Calibration method for carbon dioxide sensor. Further comprising confirming the absence of a person in the room,
The calibration of the carbon dioxide sensor according to claim 10 or 11, wherein when the absence of a person is confirmed in the room, the room carbon dioxide sensor is calibrated based on the carbon dioxide concentration measured by the calibration carbon dioxide sensor. Method.   The carbon dioxide sensor calibration method according to claim 10 or 11, wherein the room carbon dioxide sensor is calibrated at a predetermined time based on the carbon dioxide concentration measured by the calibration carbon dioxide sensor.   The carbon dioxide sensor calibration method according to claim 10, wherein a blower blows air to the room through the duct.   The carbon dioxide sensor calibration method according to claim 14, wherein the blower is included in an air conditioner, and the air conditioner and the calibration carbon dioxide sensor are arranged in an air conditioning machine room.   The method for calibrating a carbon dioxide sensor according to claim 10, wherein the calibration carbon dioxide sensor is disposed in an attic of the room.   The carbon dioxide sensor calibration method according to any one of claims 10 to 16, wherein when the room carbon dioxide sensor is calibrated, the entry of outside air into the room is blocked or suppressed.   The carbon dioxide sensor calibration method according to any one of claims 10 to 17, wherein the calibration carbon dioxide sensor is calibrated at an arbitrary time.