JP2004132639A - Air-conditioning control apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an air-conditioning control apparatus for reducing the axial power of an air supply fan by reducing the pressure loss of a filter in order to perform an energy-saved operation. <P>SOLUTION: This apparatus has a dust sensor for detecting the dust in a room, and the bypass damper of the filter is opened and closed while monitoring the dust quantity in the room to bypass part of the air quantity passed through the filter, whereby the internal static pressure of an air conditioner is reduced, and the air quantity control by an inverter is performed to reduce the shaft power of the fan. <P>COPYRIGHT: (C)2004,JPO

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a damper control method for reducing a filter loss of an air conditioner.
[0002]
[Prior art]
Conventionally, this type of air conditioner will be described with reference to FIGS. FIG. 4 shows a conventional standard air conditioner (for example, Non-Patent Document 1) in which a filter 101 is incorporated in the air conditioner to remove the amount of floating dust generated from the room, Dust is collected by the side filter 102, and fine floating dust is collected by the secondary filter 103. Here, if the filter is clogged due to the elapse of the operation time of the air conditioner, the in-machine static pressure of the air conditioner increases, and the amount of air supplied by the air supply fan 104 is reduced. In order to secure the required air volume, the shaft power of the air supply fan 104 increases as the filter 101 becomes clogged. Then, when the amount of floating dust increases in the filter 101 and the signal of the differential pressure switch 106 for detecting the differential pressure across the filter 101 is output, the primary filter 102 is washed and the secondary filter is replaced, and the filter is clogged. Was eliminated.
[0003]
On the other hand, a method using a conventionally used damper will be described as a method for reducing energy. FIG. 5 shows a conventional standard total heat exchanger air conditioner. In the cooling mode and the heating mode, the face damper 202 of the total heat exchanger 201 is opened, the bypass damper 203 is closed, and the exhaust 204 and the outside air 205 are opened. Is performed through the total heat exchanger 201, but when the outside air is to be cooled in an intermediate period or the like, the face damper 202 of the total heat exchanger 201 is closed, the bypass damper 203 is opened, and the exhaust 204 and the outside air 205 are bypassed. Ventilation through airways. As a result, in the outside air cooling mode, the resistance loss of the total heat exchanger 201 is reduced in the outside air cooling mode as compared with the operation in the cooling mode and the heating mode, and the in-machine static pressure of the air conditioner is reduced. And the supply air volume of the air supply fan 207 increases to exceed the required air volume. However, the excess power is reduced by the inverter 208 to reduce the shaft power to reduce the shaft power.
[0004]
[Non-patent document 1]
Handbook of Air Conditioning and Sanitary Engineering, 12th Edition, Design of Air Conditioning Equipment (Page 113, Figs. 3 and 13)
[Problems to be solved by the invention]
According to such a conventional method of removing airborne dust in a room by a primary filter and a secondary filter, if the airborne dust is collected on the filter due to the operation time of the air conditioner, as the airborne dust becomes clogged in the filter. The pressure loss of the filter occurs, and the air volume of the air supply fan decreases. Therefore, since the rotation speed of the air supply fan is increased by the inverter in order to secure the required air volume in the room, the shaft power of the air supply fan increases, and when the pressure loss of the filter is high, the energy loss of the air supply fan is large. There was a problem.
[0006]
The present invention has been made to solve such a conventional problem, and in a situation where the generation of floating dust in a room is small, a bypass air path is provided in parallel with a filter, and all air is supplied to a filter having a high pressure loss. It is an object of the present invention to provide an air conditioner that reduces the static pressure inside the air conditioner by branching to a bypass air path without passing the air conditioner.
[0007]
[Means for Solving the Problems]
The air conditioning control apparatus according to the present invention is characterized in that an air supply fan that blows air into a room, an inverter that varies the number of revolutions of the air supply fan, a cooling coil and an overheat coil that exchange heat between a heat medium and air. And an air conditioner including a primary filter and a secondary filter disposed upstream of the primary air filter and the secondary filter that removes indoor air, and a dust sensor that detects an amount of indoor air floating dust in a return air ventilation path; A dust measuring means for measuring the amount of suspended dust from the magnitude of the output value of the dust sensor; and a direct heat exchanger for filtering a part of excess air filtered by the primary filter without ventilation filtration by the secondary filter. A bypass air path is provided for introducing air into the apparatus, and a bypass damper for opening and closing the bypass air path is provided, and the dust detection value detected by the dust measurement means is based on the magnitude of the floating dust amount in advance. The level is set to a limit value and a lower limit value, and a damper opening / closing means for opening the bypass damper when the dust detection value is equal to or less than the lower limit value and for closing the bypass damper when the dust detection value is equal to or more than the upper limit value is provided. It is characterized by having.
[0008]
The present invention according to claim 2 is arranged such that an air supply fan that blows air into a room, an inverter that varies the number of revolutions of the air supply fan, a heat exchanger that exchanges heat between a heat medium and air, and an upstream thereof. In an air conditioner having a primary filter and a secondary filter for removing dust from indoor air, a part of excess air filtered by the primary filter is directly filtered without being filtered by the secondary filter. It is characterized in that a bypass air passage for introducing into the heat exchanger is provided, a bypass damper for opening and closing the bypass air passage is provided, and a warm-up opening / closing means for opening the bypass damper during a warm-up time period is provided.
[0009]
BEST MODE FOR CARRYING OUT THE INVENTION
An air conditioning control apparatus according to a first embodiment of the present invention includes an air supply fan that blows air into a room, an inverter that varies the number of revolutions of the air supply fan, a cooling coil that exchanges heat between a heat medium and air, and In an air conditioner including an overheat coil and a primary filter and a secondary filter disposed upstream and configured to remove indoor air, a dust sensor for detecting a floating dust amount of indoor air in a return air passage of the air conditioner. And a dust measuring means for measuring the amount of suspended dust from the magnitude of the output value of the dust sensor; and a part of excess air filtered by the primary filter is not directly filtered by the secondary filter, A bypass air path is provided for introduction to the exchanger, and a bypass damper for opening and closing the bypass air path is provided, and the dust detection value detected by the dust measuring means is a magnitude of the floating dust amount in advance. The level is set to an upper limit value and a lower limit value.When the dust detection value is equal to or less than the lower limit value, the bypass damper is opened, and when the dust detection value is equal to or more than the upper limit value, damper opening / closing means for closing the bypass damper is provided. It is provided. As described above, the state of the suspended dust in the room is grasped by measurement, and a part of the processing air is branched into the bypass air passage, so that the suction pressure of the fan can be reduced, and the energy can be reduced.
[0010]
An air conditioning control device according to a second embodiment of the present invention includes an air supply fan that blows air into a room, an inverter that varies the number of revolutions of the air supply fan, and a heat exchanger that performs heat exchange between a heat medium and air. And a primary side filter and a secondary side filter disposed upstream of the primary side filter and the secondary side filter for removing dust from the room air, and a part of excess air filtered by the primary side filter is removed by the secondary side filter. Does not provide ventilation filtration, but provides a bypass air passage for direct introduction to the heat exchanger, a bypass damper for opening and closing the bypass air passage, and a warm-up opening / closing means for opening the bypass damper during a warm-up time period. As described above, the energy saving is achieved by utilizing the bypass damper during the time period in which no floating dust is generated.
[0011]
Hereinafter, embodiments of the present invention will be described with reference to the drawings.
[0012]
【Example】
(Example 1)
FIG. 1 is a schematic diagram of an air conditioner according to an embodiment of the present invention, and FIG. 2 is a block diagram for controlling opening and closing of a bypass damper of the air conditioner of the present invention. As shown in FIG. 1, a return air damper 1 for passing return air from a room and a dust sensor 2 are arranged, and a downstream side thereof is a primary side for removing coarse floating dust of a mixed air of return air and outside air. A filter 4 and a secondary filter 5 for removing fine floating dust are sequentially arranged. Here, the primary filter 4 serves as a pre-filter, and the secondary filter 5 plays a role of a medium-performance filter. The cooling coil 6, the superheating coil 7, and the humidifier 8 are provided, and an air supply fan 10 equipped with an inverter 9 for performing a rotation speed control operation is provided. The air supply duct 11 has a static pressure sensor for measuring a duct static pressure. 12 are provided, and a variable air volume unit 13 is arranged at an entrance in each room. In addition, a bypass damper 14 serving as a bypass air passage is provided above the secondary filter 5. Further, a differential pressure switch 15 for detecting a pressure loss before the primary filter 4 and after the secondary filter 5 is provided.
[0013]
Here, when the air conditioner is operated, the floating dust generated in the room and the floating dust contained in the air mixed with the outside air are collected daily by the primary filter 4 and the secondary filter 5, and Floating dust accumulates. Then, the output signal of the dust sensor 2 for grasping the state of the floating dust in the room is received, and the dust sensor measuring means 21 measures the amount of the floating dust. The measured suspended dust amount is compared with a preset lower limit set value 23 of the dust detection value. If the measured suspended dust amount is equal to or smaller than the preset lower limit set value 23 of the dust detected value, the damper opening and closing is performed. The means 24 outputs an open output signal to the damper motor 25 to open the bypass damper 14 to bypass a part of the air passing through the secondary filter 5. As a result, the in-machine static pressure of the air conditioner decreases, the air volume of the air supply fan 10 increases, and the static pressure of the air supply duct 11 increases. Then, since the duct static pressure value measured by the static pressure sensor 12 exceeds the duct static pressure set value and the inverter 9 lowers the rotation speed of the air supply fan 10, the operating frequency of the inverter 9 is lower than before opening the bypass damper 14. And the operation can be performed with the rotation speed of the air supply fan 10 reduced, so that the shaft power of the air supply fan 10 can be reduced. In addition, when the amount of floating dust generated in the room or the like becomes large, if the dust detection value exceeds a preset upper limit set value 22 of the dust detection value, the damper opening / closing means 24 outputs a close signal to the damper motor 25, and the bypass damper 14 is closed to allow all air to pass through the secondary filter 5. Thereby, the amount of floating dust in the room is constantly monitored, and when the amount of floating dust is small, the bypass damper 14 is opened to reduce the amount of air passing through the secondary filter 5 to reduce the static pressure inside the air conditioner, The shaft power of the air fan 10 can be reduced.
[0014]
Although a dust sensor is used to detect the amount of floating dust in a room, a dust sensor or the like may be used as long as the sensor detects the amount of floating dust set in the Building Sanitation Management Law. .
[0015]
(Example 2)
Next, another embodiment will be described with reference to FIGS. FIG. 1 is a schematic diagram of the air-conditioning control device. However, here, the dust sensor 2 is unnecessary, and therefore the description will be made with the dust sensor 2 removed. FIG. 3 is a block diagram of bypass damper control during a warm-up operation of the air-conditioning control device of the present invention. In an office building or the like, a warm-up operation is performed before the operation time of the air conditioner in order to keep the room at an appropriate temperature. As shown in FIG. 3, the warm-up opening / closing means 33 receives the signal of the warm-up start time 31 and outputs an open command to the damper motor 25 to open the bypass damper 14. On the other hand, when the signal of the warm-up end time 32 is received, a close command is output to the damper motor 25 to close the bypass damper 14.
[0016]
As a result, when the air conditioner is started on the daily schedule, the air conditioner enters the warm-up mode. At that time, the bypass damper 14 is forcibly opened by the warm-up opening / closing means 33 which receives the signal of the warm-up start time 31. By reducing the amount of air passing through the secondary filter 6, the internal static pressure of the air supply fan 10 is reduced. Therefore, the airflow of the air supply fan 10 increases, and the rotation speed is reduced by the inverter 9 so that the duct static pressure measured by the static pressure sensor 12 of the air supply duct 11 is kept constant. It can be reduced. At the end of the warm-up, the bypass damper is closed by the warm-up opening / closing means 33 which receives the signal of the warm-up end time 32. As described above, in the warm-up time zone 34 from the warm-up time start 31 to the warm-up end time 32, since there is no floating dust generation source in the room and there is little need to pass through the filter, the bypass damper 14 is opened to reduce the air volume. Even if the air flow branches, air conditioning can be performed without causing any adverse effects in the room.
[0017]
【The invention's effect】
As is clear from the above invention, according to the present invention, the operation of the room while constantly monitoring the state of the amount of floating dust in the room with a dust sensor can reduce the amount of indoor dust generated from the value of the Building Sanitation Management Law. When the condition is small, an air-conditioning control device is provided that can utilize a bypass damper to reduce the amount of air passing through the filter, reduce the in-machine static pressure, and reduce the shaft power of the air supply fan for energy-saving operation. is there.
[0018]
Further, according to the present invention, even when the dust sensor is not used, the warm-up time period does not generate floating dust, so the bypass damper is used, the air volume passing through the filter is reduced, and the in-machine static pressure is reduced. It is an object of the present invention to provide an air-conditioning control device capable of performing energy-saving operation for reducing the shaft power of an air supply fan.
[Brief description of the drawings]
FIG. 1 is a schematic diagram of an air conditioner according to an embodiment of the present invention; FIG. 2 is a block diagram for controlling opening and closing of a bypass damper of the air conditioner of the present invention; FIG. Block diagram of bypass damper control during warm-up operation. FIG. 4 is a schematic diagram of a variable air volume method of a conventional air conditioner control device. FIG. 5 is a schematic diagram of a bypass damper and a face damper of a total heat exchanger of a conventional air conditioner. [Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Return air damper 2 Dust sensor 3 Outside air damper 4 Primary filter 5 Secondary filter 6 Cooling coil 7 Heating coil 8 Humidifier 9 Inverter 10 Air supply fan 11 Air supply duct 12 Static pressure sensor 13 Variable air volume unit 14 Bypass damper 15 Differential pressure switch 21 Dust sensor measuring means 22 Upper limit setting value of dust detection value 23 Lower limit setting value of dust detection value 24 Damper opening / closing means 25 Damper motor 31 Warming up start time 32 Warming up end time 33 Warming up opening / closing means 34 Warming up time zone 101 Filter 102 Primary filter 103 Secondary filter 104 Inlet fan 105 Inverter 106 Static pressure sensor 201 Total heat exchanger 202 Face damper 203 Bypass damper 204 Exhaust 205 outside air 206 cooling coil 207 air supply fan 208 inverter

Claims (2)

An air supply fan that blows air into a room, an inverter that varies the number of revolutions of the air supply fan, a cooling coil and an overheat coil that exchange heat between a heat medium and air, and dust that removes indoor air disposed upstream of the air supply fan. In an air conditioner equipped with a secondary filter and a secondary filter, a dust sensor for detecting a floating dust amount of room air in a return air ventilation path, and a floating dust amount based on a magnitude of an output value of the dust sensor. A dust measuring means for measuring, and a bypass air passage for directly introducing a part of the air to be filtered by the primary filter to the heat exchanger without filtering by the secondary filter, and opening and closing the bypass air passage A dust detection value detected by the dust measuring means is set to an upper limit value and a lower limit value based on the amount of floating dust in advance, and the dust detection value is set. There opens the bypass damper when the following lower limit set value, when the dust detection value is equal to or greater than the upper limit set value air conditioner control apparatus characterized in that a damper opening and closing means for closing the bypass damper. An air supply fan that blows air into a room, an inverter that varies the number of revolutions of the air supply fan, a heat exchanger that exchanges heat between a heat medium and air, and a primary side that is disposed upstream and performs dust removal of indoor air. In an air conditioner provided with a filter and a secondary filter, a bypass air passage for directly introducing a part of excess air filtered by the primary filter to the heat exchanger without being filtered by the secondary filter. And a bypass damper for opening and closing the bypass air passage, and a warm-up opening / closing means for opening the bypass damper during a warm-up period.

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