JP2004293886A - Operation control method and device for air conditioner - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To improve an energy saving effect by expanding a period and a time to perform the free cleaning in an air conditioner wherein the free cooling is executed in the wintertime or intermediate time to perform the energy saving operation. <P>SOLUTION: In this operation control method of the air conditioner keeping a temperature/humidity condition of a clean room 10 in a predetermined state by the air blown out from an outer conditioning machine 20 and an inner conditioning machine 30, the outside air temperature/humidity condition is monitored, a temperature of the cooling water supplied from a refrigerating machine 40 to cooling coils 22, 32 of the outer conditioning machine 20 and the inner conditioning machine 30 is automatically raised to the outside air temperature, when the outside air temperature becomes lower than a dew-point temperature corresponding to a temperature/humidity condition of a clean room, then the operation of the refrigerating machine 40 is stopped, and the cooling water cooled by a cooling tower 41 is supplied to the cooling coils 22, 32 to execute the free cooling. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to an operation control method and an operation control device for an air conditioner, and in particular, monitors temperature and humidity conditions of outside air, controls the air conditioner based on the outside air condition, and switches between normal operation and free cooling operation as needed. Accordingly, the present invention relates to an operation control method and an operation control device of an air conditioner capable of increasing the period and time during which free cooling is performed and saving energy.
[0002]
[Prior art]
Conventionally, when production environment conditions affect the quality of a product, the production equipment is installed in a clean room. In an air conditioning system using a large air conditioner (air handling device) typified by a clean room air conditioner, the temperature, humidity, and cleanliness conditions of the clean room are adjusted toward the set target temperature, humidity, and cleanliness conditions. Using a signal from a temperature sensor, a humidity sensor, and the like installed in the air conditioner, the opening degree of each of the cooling coil, heating coil, and humidifying coil valves built in the air conditioner is controlled by a PID controller.
[0003]
Generally, since many types of heat sources exist in a clean room, it is necessary to operate the air conditioner for cooling not only in the summer but also in the middle and the winter. Therefore, it is necessary to use a refrigerator to generate cold water for cooling.However, in the interim and winter seasons, the outside air temperature is low, so the outside air is used as a cold heat source, and only the cooling capacity of the cooling tower without operating the refrigerator is required. It is possible to perform free cooling in which cooling water is generated by generating cold water.
[0004]
FIG. 4 is a schematic piping system diagram showing an air conditioning system used in the free cooling management device described in Patent Document 1. During normal operation when the outside air temperature is high and free cooling operation is not performed as in summer, the passages a and b of the switching valves 64 and 65 are opened, and the cooling water from the cooling tower 61 is supplied to the refrigerator 63 by the pump 62. The heat is exchanged, and is returned to the cooling tower 61 again. The cooling water generated by the refrigerator 63 is sent to the air conditioner 67 by the pump 66.
[0005]
In a free cooling operation in an intermediate period or a winter period when the outside air temperature is low, the passages a to c of the switching valves 64 and 65 are opened, and the cooling water generated by the cooling capacity of the cooling tower 61 is pumped by the pump 62. It is sent to the air conditioner 67 and the operation of the refrigerator 63 is stopped.
[0006]
Whether the air conditioner can perform free cooling operation is judged by the air conditioner manager from data such as outside air temperature / humidity conditions, indoor temperature / humidity conditions, cooling tower cooling capacity, cooling load, etc. When it is determined that free cooling can be performed, it is common to switch the air conditioner to perform free cooling operation at an appropriate timing.
[0007]
In the free cooling management device disclosed in Patent Document 1, it is determined whether or not free cooling is effective based on the wet-bulb temperature of the outside air. The time zone is displayed on the display screen. For example, the free cooling effective time zone and the invalid time zone for each day of one month are displayed in a band graph. The case where one week has passed is determined to be the time to switch to free cooling.
[0008]
However, it is not easy to determine the timing of switching to free cooling, it takes time to switch, and it is not easy to return to normal cooling once switching to free cooling. Therefore, switching to free cooling is not performed frequently, and the administrator generally switches to free cooling only once a year. Therefore, the energy saving effect cannot be said to be sufficient, and it is required to extend the free cooling period and further improve the energy saving effect.
[0009]
[Patent Document 1]
JP-A-8-114347
[Problems to be solved by the invention]
As described above, the free cooling that uses low-temperature outside air in winter to save energy is conventionally performed only during the three months of the severe winter from mid-December to mid-March, and from October to December and from March to April. In mid-season weather conditions such as the moon, the temperature and humidity rise depending on the day, causing temperature and humidity abnormalities in the air conditioner. It was difficult to apply free cooling, and free cooling could not be performed unless cold water at 6 to 10 ° C. was stably obtained.
[0011]
The present invention has been made in view of the above circumstances, and performs free cooling, and in an air conditioner capable of energy saving operation, monitors the temperature and humidity conditions of the outside air and automatically adjusts the chilled water temperature of the refrigerator. The purpose is to change to free cooling, extend the period and time for performing free cooling, and improve the energy saving effect.
[0012]
Also, in air conditioning equipment such as clean rooms that perform free cooling, the air conditioner is composed of an external controller and an internal controller, and the temperature and humidity conditions of the clean room are quickly and accurately set to the set temperature and humidity conditions. The purpose is to:
[0013]
[Means for Solving the Problems]
An operation control method for an air conditioner according to the present invention is an operation control method for an air conditioner that maintains indoor temperature and humidity conditions in a predetermined state by air blown from an air conditioner, and monitors temperature and humidity conditions of outside air. When the outside air temperature is equal to or lower than the dew point temperature corresponding to the indoor temperature and humidity conditions, the temperature of the chilled water supplied from the refrigerator supplied to the air conditioner is increased to the outside air temperature to perform free cooling. It is characterized by.
[0014]
An operation control device for an air conditioner according to the present invention is an operation control device for an air conditioner that maintains indoor temperature and humidity conditions in a predetermined state by air blown out from the air conditioner, and includes an outside air temperature and humidity condition. Means for monitoring, and means for detecting that the outside air temperature is below the dew point temperature corresponding to the indoor temperature and humidity conditions, and when it is detected that the outside air temperature is below the dew point temperature, Control means for increasing the temperature of cold water supplied from the refrigerator to the air conditioner to the outside air temperature and performing free cooling.
[0015]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, embodiments of the present invention will be described based on examples shown in FIGS.
FIG. 1 is a schematic configuration diagram showing an air conditioning system to which the present invention is applied. If the production environment affects product quality, the production equipment is installed in a clean room. The clean room air-conditioning system includes an external conditioner 20 and an internal conditioner 30 for setting the environment of the clean room 10 to a predetermined temperature, humidity, cleanliness, and the like.
[0016]
In the clean room 10, air in a predetermined state is supplied from the external conditioner 20 and the internal conditioner 30 via the air supply duct 11, and a part of the air in the clean room 10 is supplied via the return air duct 12 to the internal conditioner 30. And a part of the air is discharged into the outside air through the exhaust duct 13. Further, inside the clean room 10, there are a temperature sensor 14 for measuring the indoor temperature and a humidity sensor 15 for measuring the indoor humidity, and the measured values by the temperature sensor 14 and the humidity sensor 15, and the temperature set in the clean room 10, The air conditioner load is calculated by comparing with the humidity condition, and the flow rate of air blown into the room from the inner conditioner 30 via the filter is determined based on the calculation result.
[0017]
The air conditioner 20 has an air filter 21, a cooling coil 22, a heating coil 23, a humidifying coil 24, and a blower fan 25, and takes in an amount of outside air corresponding to an amount discharged from the clean room 10 from an outside air intake duct 26, It is generated under the temperature and humidity conditions similar to the state of the air blown into the room, and supplied to the internal conditioner 30 via the blower fan 25 and the intermediate duct 27. Further, it has a temperature sensor 28 for measuring the temperature of the outside air taken in from the outside air intake duct 26, and a humidity sensor 29 for measuring the outside air humidity.
[0018]
The internal conditioner 30 includes an air filter 31, a cooling coil 32, a heating coil 33, a humidifying coil 34, and a blower fan 35, and controls the temperature and humidity of air returned from the clean room 10 through the return air duct 12. It is generated in a predetermined state, and blows out to the clean room 10 through the blower fan 35 and the air supply duct 11 through a filter.
[0019]
The refrigerator 40 is for supplying cold water to the cooling coils 22 and 32, and a cooling tower 41 for cooling hot water discharged from the refrigerator 40 is connected via a cooling tower pipe 42. The cold water generated by the refrigerator 40 is supplied to the cooling coil 22 of the external conditioner 20 and the cooling coil 32 of the internal conditioner 30 via the cold water pipe 43.
[0020]
In addition, during free cooling in which the air conditioner is operated without operating the refrigerator 40, the cooling valves 22a and 32a are fully opened, the compressor of the refrigerator 40 is stopped, and the pump is operated to cool the cooling tower 41. It is configured such that free cooling using cold water cooled by the capacity is started.
[0021]
Therefore, cold water is supplied from the refrigerator 40 to the cooling coil 22 of the external conditioner 20 and the cooling coil 32 of the internal conditioner 30 via the cold water pipe 43, and the supply amount is controlled by the cooling valves 22a and 32a. Is done.
[0022]
Hot water is supplied from the boiler 50 to the heating coil 23 of the external adjuster 20 and the heating coil 33 of the internal adjuster 30 via a hot water pipe 51, and the supply amount is controlled by hot water valves 23a and 33a.
[0023]
Hot water is supplied from the boiler 50 to the humidifying coil 24 of the external conditioner 20 and the humidifying coil 34 of the internal conditioner 30 via a hot water pipe 51, and the supply amount of hot water to each is controlled by the humidifying valves 24a and 34a. Controlled.
[0024]
In the air conditioning system used for the clean room as described above, heat generated in the clean room 10 is generated by cooling air returned from the clean room 10 to the internal conditioner 30 by the cooling coil 32 in the internal conditioner 30. The heat is removed.
[0025]
Further, a part of the air in the clean room 10 was discharged to the outside of the clean room 10, the same amount of outside air was taken in from the external conditioner 20, and dust was removed by the air filter 21 in the external conditioner 20, and the air was cleaned. The air is cooled and dehumidified by the cooling coil 32, the dehumidified air is heated to a predetermined temperature by the heating coil 23, and the air heated to the predetermined temperature is humidified by the humidification coil 24 and supplied to the internal conditioner 30 side. I do.
[0026]
The air supplied from the external conditioner 20 is mixed with the air returned from the clean room 10 and then supplied to the internal conditioner 30 to be blown into the clean room 10 with the target of the set temperature and humidity conditions. . Further, a filter is provided at the air outlet of the clean room 10 to remove dust, thereby ensuring a predetermined cleanliness.
[0027]
FIG. 2 is a diagram showing a main part of a psychrometric chart for explaining an embodiment of an operation control method of an air conditioner according to the present invention. In the following embodiments, the indoor temperature and indoor humidity (relative humidity) conditions set in the clean room 10 are 24 ° C. and 45%, respectively, and the operation of the air conditioner in winter when the outside air temperature is lower than the indoor temperature is taken as an example. The temperature and humidity conditions in the room in this case are indicated by a point A on the psychrometric chart shown in FIG. 2, and the dew point temperature of the air at the point A is 11 ° C. and the absolute humidity is 8.5 g / kg. .
[0028]
Hereinafter, how the air conditioner is operated and controlled when the temperature and humidity conditions of the outside air are different will be described based on a specific example.
(B) When the temperature and humidity (relative humidity) of the outside air are 16 ° C. and 80%, respectively. In this case, the temperature and humidity conditions of the outside air are indicated by a point B on the psychrometric chart shown in FIG. The dew point temperature of the air in the state is 12.5 ° C., and the absolute humidity is 9.0 g / kg. Since the absolute humidity of the outside air is higher than the absolute humidity of the air in the state of the point A, it is necessary to perform the dehumidifying operation of the air conditioner. The operation of the refrigerator is controlled so as to be -10C. Then, when the outside air of 16 ° C. taken in from the outside air intake duct 26 is cooled to the dew point temperature or less and becomes saturated air of 11 ° C. or less, the heating coil 23 of the outside air conditioner 20 increases the temperature of the air to the clean room 10 by the heating coil 23. Heat. At the inlet side, the air from the external air conditioner 20 and the return air from the clean room 10 are mixed, and the indoor temperature / humidity conditions (24 ° C., 45 ° C.) are set. %). In this case, the air conditioner is not operated for free cooling.
[0029]
(B) When the temperature and humidity of the outside air are 16 ° C. and 55%, respectively. In this case, the temperature and humidity conditions of the outside air are indicated by a point C on the psychrometric chart shown in FIG. Has a dew point of 6.5 ° C. and an absolute humidity of 6.2 g / kg. Since the absolute humidity of the outside air is lower than the absolute humidity of the air at the point A, it is not necessary to perform the dehumidifying operation of the air conditioner, and free cooling is possible. Therefore, the temperature of the chilled water generated by the refrigerator is automatically and gradually increased to the outside air temperature of 16 ° C., and thereafter, the chilled water is supplied to the cooling coil 22 of the external controller 20 and the cooling coil 32 of the inner controller 30, Start energy-saving operation by free cooling without operating the refrigerator. Since the absolute humidity of the air in the state at the point C is 6.2 g / kg, the humidity of 8.5-6.2 = 2.3 g / kg is supplied from the humidifying coil 24 to the shortage of the humidity. As in the case of (a), the internal conditioner 30 mixes the air from the external conditioner 20 with the return air from the clean room 10 at the entrance side, and sets the indoor temperature and humidity conditions. Control is performed so as to satisfy the temperature and humidity conditions.
[0030]
As described above, when the air conditioner is controlled so that the temperature and humidity of the room in which the clean room is set are set, the outside air condition needs to satisfy the following conditions in order to operate the air conditioner by energy saving by free cooling. is there.
Dew point temperature corresponding to indoor temperature and humidity conditions> Outside air temperature [0031]
Therefore, during the energy saving operation by free cooling in the case of (b), the outside air condition changes and the dew point temperature corresponding to the indoor temperature / humidity condition becomes
If the dew point temperature corresponding to the indoor temperature / humidity condition is smaller than the outside air temperature, the air conditioner is shifted from the free cooling operation to the normal operation for operating the refrigerator, and the cooling valve 22a, 32a is returned to the normal control, and the temperature of the chilled water is automatically lowered little by little to return to the normal set temperature so that the temperature and humidity conditions of the clean room do not become abnormal.
[0032]
FIG. 3 is a diagram illustrating an example of the arrangement of air conditioners in a clean room. FIG. 3A shows an example in which an air conditioning system for the clean room 10 includes an external air conditioner 20 and an internal air conditioner 30. In detail, the configuration shown in FIG. The inner conditioner 30 functions as an air conditioner that quickly and accurately adjusts the temperature and humidity conditions of the clean room, and is suitable for an air conditioner for a clean room having a large displacement.
[0033]
FIG. 3B shows an example in which the air conditioning system includes an air conditioner 30 ′. One air conditioner 30 ′ regulates the air taken in from the outside air and the return air from the clean room. Since the air conditioner 16 is provided, the air conditioner is suitable for an air conditioner that generates a large amount of heat in a clean room.
[0034]
FIG. 3B shows an example in which the clean room 10 includes an air conditioner 30 ′. The air conditioner 30 ′ adjusts the air taken in from the outside air and the return air from the clean room, and has a simple configuration. Suitable for air conditioners for small and clean rooms.
[0035]
Although the above embodiment has been described as an air conditioner for a clean room, it can be applied to general buildings such as semiconductors, electronic materials, optical fibers and related parts, factories and workplaces that produce precision machines, office buildings, and houses. It is possible.
[0036]
【The invention's effect】
As is apparent from the above description, according to the present invention, during winter and intermediate periods other than summer, the temperature and humidity conditions of the outside air are monitored, and the chilled water temperature of the refrigerator is automatically changed to shift to free cooling. By doing so, it is possible to extend the period and time for performing free cooling and to save energy.
[0037]
In the air conditioner that performs free cooling, the air conditioner is composed of an external air conditioner and an internal air conditioner, and the temperature and humidity conditions of the clean room are quickly and accurately set to the temperature and humidity conditions. , Can be held.
[Brief description of the drawings]
FIG. 1 is a schematic configuration diagram showing an air conditioning system to which the present invention is applied.
FIG. 2 is a diagram showing a main part of a psychrometric chart for explaining an embodiment of an operation control method of an air conditioner according to the present invention.
FIG. 3 is a diagram illustrating an example of an arrangement of air conditioners in a clean room.
FIG. 4 is a schematic piping system diagram showing an air conditioning system used in a conventional free cooling management device.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 10 ... Clean room, 11 ... Supply air duct, 12 ... Return air duct, 13 ... Exhaust duct, 14 ... Temperature sensor, 15 ... Humidity sensor, 20 ... Outside air conditioner, 21 ... Air filter, 22 ... Cooling coil, 23 ... Heating Coil, 24: Humidifying coil, 25: Ventilation fan, 26: External air intake duct, 27: Intermediate duct, 28: Temperature sensor, 29: Humidity sensor, 30: Internal adjuster, 31: Air filter, 32: Cooling coil, 33 ... heating coil, 34 ... humidification coil, 35 ... blower fan, 40 ... refrigerator, 41 ... cooling tower, 42 ... cooling tower piping, 43 ... cold water piping, 50 ... boiler, 51 ... hot water piping.

Claims (4)

An operation control method of an air conditioner for maintaining indoor temperature and humidity conditions in a predetermined state by air blown from an air conditioner, wherein the outside air temperature and humidity conditions are monitored, and the outside air temperature is adjusted to the indoor temperature and humidity. An operation control method for an air conditioner, wherein when the temperature of the air conditioner becomes equal to or lower than a dew point temperature, the temperature of a chilled water supplied from the refrigerator to the air conditioner is raised to the outside air temperature to perform free cooling. An operation control device of an air conditioner that maintains indoor temperature and humidity conditions in a predetermined state by air blown out from an air conditioner, and a unit that monitors temperature and humidity conditions of outside air; And means for detecting that the temperature is below the dew point temperature corresponding to the humidity condition, and when it is detected that the outside air temperature is below the dew point temperature, the temperature of the chilled water from the refrigerator supplied to the air conditioner is detected. An operation control device for an air conditioner, comprising control means for performing free cooling by raising the temperature to the outside air. The operation control device for an air conditioner according to claim 2, wherein the air conditioner includes an external air conditioner and an internal air conditioner, and the external air conditioner generates outside air in a blown air condition of the internal air conditioner. An operation control device for an air conditioner. The operation control device for an air conditioner according to claim 3, wherein air generated by the external air conditioner and air from the room are mixed, and the mixed air is generated by the internal air conditioner in the indoor condition. An operation control device for an air conditioner, which is blown into the room.

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