JP2004125304A - Wind volume control device of air conditioner - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a wind volume control device of an air conditioner allowing a set fresh air rate to be actually led therein and wind volume flowing through zones to be accurately and rapidly kept in balanced with each other. <P>SOLUTION: In this air conditioning control device, air conditioned by a wind volume varying device is fed to a controlled area, the air in the controlled area is circulated by an air circulation device, and a part or all of the circulation air is led into an air conditioner and the remaining is exhausted to the outside for circulating the air. At the same time, fresh air is led into the air conditioner, the led air is air-conditioned by the air conditioner, and the air-conditioned air is fed to the wind volume varying device by an air supply device. The wind volume of the air led into the air conditioner for circulation is determined based on the wind volume of the air taken from the atmospheric air and the wind volume fed by the air supply device. <P>COPYRIGHT: (C)2004,JPO

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention belongs to the technical field of an air conditioner control device. More specifically, it belongs to the technical field of controlling the air volume in an air conditioner.
[0002]
[Prior art]
2. Description of the Related Art Conventionally, in a large-scale building, several rooms (controlled areas) are provided by partitioning a space, and each room is provided with a variable air supply amount adjustment unit (hereinafter, VAV) through an air supply duct from an air conditioner. The air-conditioned air is blown from a supply air outlet provided in each room by the unit, and the indoor air is returned to the air conditioner from the return air inlet and circulated. On the other hand, when the concentration of carbon dioxide (CO2) or the like in the indoor air is high, a method of discharging part of the circulated air to the outside and taking in fresh air from the outside to perform air conditioning is adopted. I have.
[0003]
In such a conventional air conditioner, a duct for guiding air is provided, and a damper (butterfly valve) is provided in the air passage to adjust the angle of the damper, thereby adjusting the amount of air flowing through the duct. Is adopted. An example of such an air conditioning control system is disclosed in Japanese Patent Laid-Open Publication No. Hei 11-344252. FIG. 5 is a schematic diagram of the overall configuration of the air conditioning system, and FIG. 7 shows a control method for determining a damper angle. Hereinafter, this air conditioning system is referred to as a conventional device 1.
[0004]
In FIG. 5, 50 is a controlled area, and 60 is a schematic diagram of the air conditioner main body. Reference numeral 80 denotes a damper control device (or an outside air intake control device). Air conditioned from the air supply duct 61 of the air conditioner main body 60 is supplied to the controlled area 50 by the air supply fan 62 in the direction of the arrow (the right arrow in the figure). A predetermined amount of air is supplied to each room in the controlled area by a VAV unit (not shown). Further, the indoor air is returned by the return air fan 64 through the return air duct 63. 65 is a heat exchanger, 66 is an outside air damper for controlling the amount of outside air intake, and the flow rate of outside air is measured by a wind speed sensor 69. 67 is an exhaust damper that controls the amount of air that discharges the returned air to the outside, and 68 is a return air damper that controls the amount of air that returns the returned air to an air conditioner (not shown).
[0005]
The wind speed calculation unit 81 obtains the wind speed V1 based on the output of the wind speed sensor 69, and the air volume calculation unit 82 calculates the actual air volume Q1 by Q1 = V1 · A1. A1 is the duct cross-sectional area. Reference numeral 83 denotes an actual air volume ratio calculation unit, and the actual air volume ratio PV1 is calculated by PV1 = (Q1 / air conditioner rated air volume) × 100%. The symbol "x" indicates multiplication. A damper control unit 94 determines an opening θ1 of the outside air damper opening 66, an opening θ2 of the exhaust damper 67, and an opening θ3 of the return air damper 68 by a method described later. Determining units 92 to 94 determine the outside air intake air flow set value. The determination unit 92 determines the minimum value S1 of the outside air intake air flow, and the determination unit 93 determines the external air intake air flow from the difference between the set value of the carbon dioxide gas and the measured value. The intake air amount S2 is determined, and the determination unit 94 determines the outside air intake air amount S3 from the difference between the supply air temperature setting value and the supply air temperature measurement value. Note that the supply air temperature measurement value is obtained by the supply air temperature sensor 51. The selector 95 determines the maximum air volume SP1 from the external air intake air volumes S1 to S3. The correction unit 96 converts the determined damper opening degrees θ1 to θ3 into control amounts θ1 ′ to θ3 ′. By this conversion, the relationship between the control amounts θ1 ′ to θ3 ′ and the air flow is linearized.
[0006]
FIGS. 6A and 6B show a method of determining the set values S2 and S3 of the outside air intake air volume by the determining unit 93 and the determining unit 94. FIG. 7 shows a table for determining the damper openings θ1 to θ3 based on the outside air intake air flow set value SP1. First, the determining unit 93 determines the outside air intake air flow rate S2 (%) in proportion to the deviation between the set value of the carbon dioxide gas and the measured value, as shown in FIG. Next, as shown in FIG. 6A, the determination unit 94 determines the outside air intake air flow rate S2 (%) in proportion to the difference between the supply air temperature setting value (or load reset value) and the supply air temperature measurement value. . The damper control unit 94 determines the maximum air volume SP1 (%) from the set values S1 (%) to S3 (%) of the external air intake air volume by the selector 95, and uses this as a control signal output to determine the damper opening shown in FIG. The damper opening degrees θ1 to θ3 are determined from the table.
[0007]
In this damper opening determination table, the outside air damper opening θ1 and the exhaust damper opening θ2 are set to the same opening. As shown in FIG. 7, the damper opening θ1 (θ2 = θ1) and the return air damper opening θ3 are such that when one damper opening is an intermediate opening or fully closed, the other damper opening is kept fully open. To decide. That is, when the control signal output is 50% or less, the damper opening θ1 (θ2) is increased from 0 to 100% as the control signal output increases while the damper opening θ3 is fully opened, and the damper opening θ1 (θ2) is increased. When the full opening is reached, the damper opening θ3 is reduced to 100 to 0% as the control signal output increases.
In the above-described conventional device 1, the damper openings θ1 to θ3 are determined by the outside air intake air amount (%). It should be noted that, in the conventional device 1, it is not necessary to satisfy θ1 (or θ2) + θ3 = 100% because the pressure loss increases as the damper opening decreases.
[0008]
Further, in a conventional device (hereinafter, referred to as a conventional device 2), the ventilation amount is assumed to be proportional to the damper opening, and the return air damper opening θ3 is determined as an operation reverse to the opening θ2 of the outside air damper. That is, θ3 = 100−θ2 (or θ1).
[0009]
[Problems to be solved by the invention]
In the above-described conventional apparatus (conventional apparatus 1 and conventional apparatus 2), the required outside air intake air ratio is determined from the deviation of the carbon dioxide concentration and the deviation of the supply air temperature, and the damper opening is directly determined from this. Therefore, when the supply air flow rate is small, the actual air flow rate that is actually set cannot be introduced, or the external air flow rate and the exhaust air flow rate do not balance well. In particular, in the conventional device 1, a situation in which the set air volume cannot be introduced from the outside air is likely to occur. The present application is an invention made to solve such a problem.
[0010]
[Means for Solving the Problems]
In order to solve the above problems, the present invention employs the following solutions. That is,
According to the first aspect of the present invention, the air conditioned by the variable air amount device is blown into the controlled area, the air in the controlled area is returned by the return air device, and part or all of the return air is circulated. Air to the air conditioner to discharge the rest to the outside, at the same time to introduce outside air to the air conditioner, air-treat the introduced air by the air conditioner, and supply the air-conditioned air to the air supply device In the air-conditioning control device configured to send air to the variable air volume device, the amount of air introduced into the air conditioner for circulation is determined from the amount of outside air intake air and the amount of air blown by the air supply device. It is characterized by. That is, the invention of claim 1 is characterized mainly in that the return air volume and the exhaust air volume to be circulated are determined based on the air volume supplied by the air supply device and the air volume of the outside air intake air.
[0011]
According to a second aspect of the present invention, in the first aspect of the present invention, the air volume of the outside air intake air is controlled based on an air volume value of a variable air volume device provided in the outside air intake duct.
That is, the invention according to claim 2 is characterized mainly in that the amount of external air introduced is controlled by the variable air volume device.
[0012]
According to a third aspect of the present invention, in the first aspect of the present invention, the amount of the outside air intake air is controlled based on an opening degree of an outside air damper provided in the outside air intake duct.
[0013]
According to a fourth aspect of the present invention, in the first to third aspects of the present invention, the air supply amount is controlled based on a frequency of a drive inverter of the air supply device.
That is, the invention of claim 4 is characterized mainly in that the supply air volume can be accurately and quickly made possible by the inverter device.
[0014]
DETAILED DESCRIPTION OF THE INVENTION
FIG. 1 shows a schematic configuration of an apparatus according to an embodiment of the present invention. FIG. 2 shows a functional block diagram of the main controller. FIG. 3 shows the relationship between the inverter frequency and the air flow. FIG. 4 shows the relationship between the air volumes. Hereinafter, the present embodiment will be described with reference to these drawings. 1 to 4, the controlled area 10 to be air-conditioned includes rooms 10a and 10b. In the rooms 10a and 10b, variable air supply flow control units (hereinafter, referred to as VAV units) 11a and 11b are provided at air supply outlets. The VAV units 11a and 11b are connected to an air supply duct 12, and air-conditioned air is supplied from an air supply fan 13. The rooms 10a and 10b are provided with return air inlets 14a and 14b, respectively, and return air is returned by a return air fan 17 through a return air duct 15.
[0015]
The VAV units 11a and 11b are provided with local controllers 15a and 15b for setting the air volume. The local controllers 15a and 15b provided in the rooms 10a and 10b are provided with a difference between the temperature sensors 16a and 16b (current room temperature) and the set room temperature. Air volumes v1 and v2 are determined. The VAV controllers 15a and 15b are connected to the zone controller 20, and data such as air volumes v1 and v2 and damper opening degrees β1 and β2 provided inside the VAV units 11a and 11b are input to the zone controller 20. . The zone controller 20 calculates the total required air volume V and the maximum opening degree βm, and sends them to the controller 25. Note that V = v1 + v2 and βm = max (β1, β2).
[0016]
The air conditioner main body 30 is partitioned into air paths such as an air supply path 31, a return air path 32, and an external air path 33. Are provided. Further, the return air passage 32 is provided with the return air fan 16, the downstream of which is connected to the exhaust duct 36, and the ventilation hole 37 is provided at the boundary with the air supply passage 31. An outside air damper 38 and a return air damper 39 for limiting the air volume are provided in the exhaust duct 36 and the vent 37, respectively. The outside air passage 33 is connected to an outside air intake duct 40, and the outside air intake duct 40 is provided with a VAV unit 41 (and, if necessary, an outside air fan 42) for taking in outside air.
[0017]
Further, a temperature sensor 43 is provided in the air supply duct 12, and an output thereof is connected to an input side of the main controller 25. Similarly, the return air duct 15 is provided with a temperature sensor 44 and a carbon dioxide (CO 2) concentration sensor 45, and the outputs thereof are all connected to the input side of the main controller 25. On the output side of the controller 25, in addition to the inverter 13a (drive motor controlled by inverter) of the air supply fan 13 and the inverter 17a of the return air fan 17, an actuator 38a for controlling the opening degree of the outside air damper 38, a return air damper 39 The actuator 39a for controlling the opening of the air conditioner is connected to a controller 41a for controlling the air volume of the outside air VAV unit 41.
[0018]
The main controller 25 will be described with reference to FIG. As described above (FIG. 1), the zone controller 20 supplies the air supply air volume (substantially equal to the actual air volume) v1... Vn and the damper opening from the VAV units 11a and 11b provided in the respective rooms 10a and 10b of the controlled area. The signals of the degrees β1... Βn are received, the total supply air volume V and the maximum opening degree βm are obtained, and the calculation result is output to the main controller 25. Although the number of rooms is n = 2 in FIG. 1, it is not limited to this. The air supply inverter frequency determination unit 46 determines the air supply air volume Va in consideration of the maximum opening degree βm. That is, when the maximum opening βm is 100%, the supply air volume Va is made larger than the total supply air volume V, and the maximum opening βn is reduced to 100% or less. As a result, the maximum opening degree βm is set to 100% or less (for example, 90%). Since the relationship between the supply air volume Va and the inverter frequency has a linear relationship as shown in FIG. 3A, the inverter frequency N1 is determined using this relationship.
[0019]
Next, the return air inverter frequency determination unit 47 determines the inverter frequency of the return air fan 16. As shown in FIG. 3B, the inverter frequency N2 is determined so that the return air inverter frequency has a certain ratio between the return air volume and the supply air volume. The outdoor air intake air flow rate determination unit 26 during outdoor air cooling determines the outdoor air intake air flow w1 in consideration of the operation mode and the difference between the return air temperature and the outdoor air temperature. That is, in the case of the outside air cooling permission mode, when the outside air temperature is lower than the return air temperature, the determination is made in consideration of the cooling efficiency and the like. The outside air intake air volume determining unit 27 based on the carbon dioxide gas concentration determines the outside air intake air volume w2 such that when the concentration of carbon dioxide gas contained in the return air is high, the concentration is reduced to a predetermined reference value or less.
[0020]
The selector unit 28 obtains the maximum air volume Wm from the external air intake air volumes w1 and w2 determined by the external air intake air volume determination units 26 and 27. The air volume of the outside air VAV unit 41 is set to be the maximum air volume Wm. The outside air required air volume ratio determining unit 29 sets the rated air volume of the air supply fan 13 to 100%, and obtains a ratio (= Wmx100% / rated air volume x100%) based on this. The exhaust damper opening determining unit 49 determines the opening of the exhaust damper 38 so that the outside air intake air flow Wm and the exhaust air flow are equal. The return air damper opening determination unit determines the opening of the return air damper 39 so that the return air flow Vk is equal to the difference between the supply air flow Va and the outside air intake flow Wm, that is, Vk = Va−Wm. The relationship between the air volume and the degree of opening of the damper can be determined based on experimental results or data in a catalog or the like as in the related art. Note that the exhaust air volume ratio is the same as the external air required air volume ratio (that is, θ1 = θ2). Alternatively, a3 and a3 may be used as parameters, and θ3 = a−bx required outside air flow rate ratio. For example, if the maximum outside air flow ratio to the design supply air flow is 0.35, and if the required air supply flow ratio is 50%, the opening degree θ3 of the return air damper is θ3 = 100−0.35 · 50% = 87. 0.5%.
[0021]
FIG. 4 shows the relationship among the supply air volume, the return air volume, the outside air intake air volume, the exhaust air volume, and the air volume passing through the return air damper, where each air volume is defined as 100% of the rated air volume of the air supply fan 13. Expressed as a ratio. For example, FIG. 4A shows 100% when the supply air volume is the same as the rated air volume. The return air volume is also 100%, the outside air intake air volume, the exhaust air volume is 35%, and the air volume passing through the return air damper is 65%. FIG. 4B shows a case where the supply air volume and the return air volume are both 50%, the outside air intake air volume and the exhaust air volume are 35%, and the air volume passing through the return air damper is 15%. FIG. 4C shows a case where the supply air volume and the return air volume are both 35%, the outside air intake air volume and the exhaust air volume are 35%, and the air volume passing through the return air damper is 0%.
[0022]
The present embodiment is configured as described above, and has the following functions and effects. That is, the amount of air supplied to the controlled area is determined in consideration of the amount of air actually supplied to each room in the controlled area and the maximum opening of the damper of the VAV unit provided in each room. When the air volume is smaller than the rated air volume, there is a margin in the control range. Further, the supplied air volume is controlled by an inverter, so that an accurate air volume can be supplied. In addition, it is necessary to introduce an accurate air flow for the air flow introduced from the outside air in order to satisfy a required standard (carbon dioxide concentration or the like). However, since the air flow is performed by the VAV unit 41, an accurate air flow can be introduced. Since the opening degrees of the return air damper 39 and the exhaust damper 38 are determined based on these accurate air volumes, the air flows (the air supply path 31, the return air path 32, and the external air path 33) as a whole. The air volume is also accurate. Further, the inverter and the VAV unit are active components for forcibly determining the air volume, and the flow rates flowing through the respective zones are determined so as to be balanced. It is possible to reach.
[0023]
As described above, the embodiments and examples of the present invention have been described in detail with reference to the drawings. However, the specific configuration is not limited to the examples, and there are design changes and the like without departing from the gist of the present invention. Is also included in the present invention. For example, a damper may be provided instead of the VAV for controlling the amount of outside air introduced, and the opening of the damper may be controlled.
[0024]
【The invention's effect】
As described above, according to the configuration of the present invention, the invention according to claim 1 determines the amount of circulated return air and the amount of exhaust air based on the amount of air supplied by the air supply device and the amount of external air intake air. Therefore, the effect that the air volume flowing through each part is close to the design value can be obtained. Therefore, an effect that appropriate air conditioning becomes possible is obtained. Further, since the required flow rate of the outside air intake air can be introduced as controlled, the effect of improving the quality of the air conditioning system can be obtained.
[Brief description of the drawings]
FIG. 1 shows a schematic configuration of an apparatus according to an embodiment of the present invention.
FIG. 2 is a functional block diagram of a main controller according to the embodiment.
FIG. 3 shows a relationship between an inverter frequency and an air volume.
FIG. 4 shows a relationship between air volumes in each zone.
FIG. 5 shows a configuration diagram of a conventional device.
FIG. 6 shows the setting of the outside air intake air volume of the conventional apparatus.
FIG. 7 shows a table for determining a damper opening of the conventional device.
[Explanation of symbols]
10 (10a, 10b) Controlled zone 11 (11a, 11b) VAV unit 13 (13a) Supply device 16 (16a) Return device 20 Zone controller 25 Main controller 28 Selector 38 Exhaust damper 39 Return air damper 41 For intake of outside air VAV units 43 and 44 Temperature sensor 45 Carbon dioxide concentration sensor 46 Air supply inverter frequency determination unit 47 Return air inverter frequency determination unit 48 Return air damper opening degree determination unit 49 Exhaust damper opening degree determination unit

Claims (4)

The air conditioned by the variable air volume device is blown into the controlled area, the air in the controlled area is returned by the return air device, and introduced into the air conditioner to circulate a part or all of the return air. The remaining air is discharged to the outside, and at the same time, outside air is introduced into the air conditioner. In the air conditioning control device, the air volume of the air introduced into the air conditioner for circulation is determined from the air volume of the outside air intake air and the air volume of the air supply device. Control device. The air flow control device for an air conditioner according to claim 1, wherein the air flow of the outside air intake air is controlled based on the air flow value of a variable air flow device provided in the outside air intake duct. 2. The air flow control device for an air conditioner according to claim 1, wherein the air flow of the outside air intake air is controlled based on an opening degree of an outside air damper provided in the outside air intake duct. 3. The air volume control device for an air conditioner according to claim 1, wherein the air volume is controlled based on a frequency of a drive inverter of the air supply device.

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