JP7563808B1 - Air conditioning system and control method - Google Patents

Abstract

[Problem] To provide an air conditioning system capable of introducing outside air to further enhance the effect of energy saving. [Solution] An air conditioning system 1 includes an air conditioner 10 that introduces outside air into an air-conditioned space 3, a first acquisition unit 20 that acquires a predicted temperature of the outside air, and a control unit 40 that controls the timing of introduction of the outside air by the air conditioner 10 into the air-conditioned space 3 using the predicted temperature of the outside air acquired by the first acquisition unit 20. When cooling the air-conditioned space 3, the control unit 40 controls the air conditioner 10 so that the lowest temperature outside air is introduced into the air-conditioned space 3, and when heating the air-conditioned space 3, the control unit 40 controls the air conditioner 10 so that the highest temperature outside air is introduced into the air-conditioned space 3. [Selected Figure] Figure 1

Description

The present invention relates to an air conditioning system that introduces outside air into an air-conditioned space.

Conventionally, in an air conditioning system that conditions an air-conditioned space that has an opening to the outdoors, when the temperature of the outdoor air is on the target side of temperature adjustment relative to the temperature of the air-conditioned space, the air conditioning system is controlled so that air flows into the air-conditioned space from the opening (see, for example, Patent Document 1). Such a method can achieve energy savings.

JP 2020-115053 A

However, in conventional air conditioning systems, the decision as to whether to introduce outside air is made based on the temperature difference between indoors and outdoors at the time of control. This poses the problem that the energy saving effect is limited. For example, in commercial facilities and other places where the air conditioning is not operated at night, the low temperature outside air in the early summer morning cannot be introduced into the air-conditioned space, and opportunities to introduce outside air are limited.

The present invention has been made to solve the above problems, and aims to provide an air conditioning system etc. that can introduce outside air to further enhance the energy saving effect.

In order to achieve the above object, an air conditioning system according to one aspect of the present invention includes an air conditioning device that introduces outside air into an air-conditioned space, a first acquisition unit that acquires a predicted temperature or predicted specific enthalpy of the outside air, and a control unit that controls the timing of introduction of the outside air into the air-conditioned space by the air conditioning device using the predicted temperature or predicted specific enthalpy of the outside air acquired by the first acquisition unit, and the control unit controls the air conditioning device so that the outside air that has the smallest thermal load on the air-conditioned space is introduced into the air-conditioned space.

This configuration makes it possible to introduce outside air at an optimal temperature or specific enthalpy into the air-conditioned space, thereby further increasing the energy saving effect.

In an air conditioning system according to one aspect of the present invention, the air conditioning device is capable of introducing outside air taken in through a plurality of outside air inlets located at different positions into the air-conditioned space, and further includes a second acquisition unit that acquires the current temperature or current specific enthalpy of the outside air at each of the plurality of outside air inlets, and the control unit may control the air conditioning device so that, when the outside air is introduced into the air-conditioned space by the air conditioning device, the outside air taken in through the outside air inlet that has the smallest heat load on the air-conditioned space is introduced into the air-conditioned space, using the current temperature or current specific enthalpy of the outside air acquired by the second acquisition unit.

With this configuration, it becomes possible to introduce outside air into the air-conditioned space from the outside air inlet that has the most suitable temperature or specific enthalpy among the multiple outside air inlets. As a result, the energy saving effect can be further improved.

In addition, the air conditioning system according to one aspect of the present invention may further include a third acquisition unit that acquires the temperature or specific enthalpy of the air-conditioned space, and the control unit may control the air conditioning device so that outside air is introduced into the air-conditioned space within a range in which the temperature or specific enthalpy acquired by the third acquisition unit does not exceed a target value in the direction of adjustment of the temperature or specific enthalpy.

With this configuration, for example, when cooling is performed on the air-conditioned space and the temperature of the outside air is lower than the target temperature value for the air-conditioned space, it is possible to prevent excessive outside air from being taken into the air-conditioned space. As a result, it is possible to reduce the energy required to introduce outside air.

In addition, in an air conditioning system according to one aspect of the present invention, the control unit may control the air conditioning device so that the amount of outside air introduced into the air-conditioned space during the outside air introduction period increases as the daily difference in the predicted temperature or predicted specific enthalpy acquired by the first acquisition unit increases.

This configuration allows more outside air to be introduced when the effect of introducing outside air is high. For example, even if night purging is performed uniformly in the summer, it may not promote energy conservation. This is because the outside temperature at night may not drop significantly, and the outside temperature during the day may not rise much. If more outside air is introduced in a situation where introducing outside air is not effective, extra energy will be consumed to introduce the outside air. On the other hand, by adjusting the amount of outside air introduced according to the daily difference in the predicted outside air temperature or predicted specific enthalpy, such extra energy consumption can be reduced.

A control method according to one aspect of the present invention is a method for controlling an air conditioner that introduces outside air into an air-conditioned space, and includes a step of acquiring a predicted temperature or predicted specific enthalpy of the outside air, and a step of controlling the timing of introducing the outside air into the air-conditioned space by the air conditioner using the acquired predicted temperature or predicted specific enthalpy of the outside air, and includes a step of controlling the air conditioner in the step of controlling the timing of introducing the outside air so that the outside air that has the smallest heat load on the air-conditioned space is introduced into the air-conditioned space.

According to an embodiment of the air conditioning system of the present invention, it becomes possible to introduce outside air with an optimal temperature or specific enthalpy into the air-conditioned space, thereby further enhancing the energy saving effect.

FIG. 1 is a schematic diagram showing a configuration of an air conditioning system according to an embodiment of the present invention; FIG. 2 is a functional block diagram showing a configuration related to control of an air conditioning system according to the embodiment. FIG. 2 is an external perspective view showing an example of a building in which an air-conditioned space exists according to the embodiment; FIG. 13 is a diagram showing changes in predicted outside air temperature in the embodiment. A flowchart showing the operation of the air conditioning system according to the embodiment. FIG. 11 is a functional block diagram showing another example of the configuration related to control of the air conditioning system according to the embodiment.

The air conditioning system and the method for controlling the air conditioning device according to the present invention will be described below using an embodiment. Note that in the following embodiments, components and steps with the same reference numbers are the same or equivalent, and repeated explanations may be omitted. The air conditioning system according to this embodiment uses a predicted temperature of the outside air to introduce outside air at a temperature suitable for introduction into the air-conditioned space into the air-conditioned space.

Figure 1 is a schematic diagram showing the configuration of an air conditioning system 1 according to this embodiment, and Figure 2 is a functional block diagram showing the configuration related to the control of the air conditioning system 1. The air conditioning system 1 includes an air conditioner 10, a first acquisition unit 20, a second acquisition unit 30, and a control unit 40, and may further include a duct 61 for supply air (SA) to the air-conditioned space 3 and a duct 62 for return air (RA) from the air-conditioned space 3, as necessary. The air-conditioned space 3 is a space to be conditioned by the air-conditioning system 1. The air-conditioned space 3 is not particularly limited, and may be, for example, an office, a commercial facility, a store, a station, an airport, an underground mall, etc.

The air conditioner 10 introduces outside air (OA) taken in through an outside air inlet into the air-conditioned space 3. In this embodiment, as shown in FIG. 1, a case will be mainly described in which the air conditioner 10 can introduce outside air OA1 to OA3 taken in through three outside air inlets 51 to 53, respectively, into the air-conditioned space 3. The air conditioner 10 may also adjust the temperature of the air supplied to the air-conditioned space 3, for example. In this embodiment, a case will be mainly described in which the air conditioner 10 both introduces outside air into the air-conditioned space 3 and adjusts the temperature of the air in the air-conditioned space 3.

The outdoor air inlets 51 to 53 are intakes for taking in outdoor air into the ducts 14b to 14d. The outdoor air inlets 51 to 53 may be located at different positions, for example. The different positions may be different positions in at least one of the vertical and horizontal directions. As an example, as shown in FIG. 3, the outdoor air inlets 51 to 53 may be located at different positions in the building 5 in which the air-conditioned space 3 exists. It is preferable that the outdoor air inlets 51 to 53 are located so that the temperature of the outdoor air at each position is different. Therefore, for example, when the outdoor air inlets 51 to 53 are located on the wall surface of the building 5 in which the air-conditioned space 3 exists, at least two of the outdoor air inlets 51 to 53 may be located on the wall surface facing different directions. Specifically, the outdoor air inlet 51 may be located on the north-facing wall surface of the building 5, and the outdoor air inlet 53 may be located on the west-facing wall surface of the building 5. In this embodiment, the case where three outside air inlets 51 to 53 are used will be mainly described, but the number of outside air inlets may be, for example, one, or any number of two or more. Ideally, for example, it is preferable that an outside air inlet is provided on each wall surface facing each direction of the building. It is even more preferable, for example, that the outside air inlets are provided at different vertical positions on each wall surface. As an example, an outside air inlet may be provided at an upper position and a lower position on each of the north-facing wall surface, east-facing wall surface, south-facing wall surface, and west-facing wall surface of the building. In this case, the number of outside air inlets is eight.

The air conditioner 10 may, for example, include fans 11 and 12, a coil 13, a return air duct 14a, outside air introduction ducts 14b to 14d, an exhaust air (EA) duct 14e, and dampers 15a to 15e provided in the ducts 14a to 14e, respectively. One end of the exhaust air duct 14e may, for example, be connected to the return air duct 14a at a position between the damper 15a and the blower 12.

The blower 11 sends return air or outside air to the air-conditioned space 3. In addition, when the temperature or humidity of the air is adjusted by the coil 13, the adjusted air is sent to the air-conditioned space 3 by the blower 11.

The blower 12 exhausts the return air from the air-conditioned space 3 and/or sends it to the blower 11. The ratio of exhaust to sending air to the blower 11 may be changed, for example, by adjusting the air volume of the dampers 15a and 15e.

The coil 13 is a heat exchanger for adjusting the temperature of the air. The coil 13 may be supplied with cold water or hot water from a heat source device 9 having, for example, a boiler or a refrigerator. When cooling is performed by the air conditioner 10, cold water may be supplied from the heat source device 9 to the coil 13, and when heating is performed by the air conditioner 10, hot water may be supplied from the heat source device 9 to the coil 13. The coil 13 may also adjust the humidity of the air, i.e., dehumidify it, for example. In this case, cold water at a temperature equal to or lower than the dew point temperature of the air passing through the coil 13 may be supplied to the coil 13.

The volume of the supply air supplied to the air-conditioned space 3 may be adjusted, for example, by the blower 11, or by a variable air volume device (VAV) provided in the duct 61 through which the supply air passes. When adjusting the volume of the air by the blower 11, the air conditioner 10 may use a blower 11 capable of adjusting the volume of the air, for example, an inverter-controlled blower 11 or a blower 11 using a DC motor.

Dampers 15a to 15e may be, for example, motor dampers, and the air volume may be adjustable by the control unit 40. For example, by adjusting the air volume of dampers 15a and 15e, the proportion of the return air that is exhausted can be changed. Also, for example, by adjusting the air volume of dampers 15b to 15d, the outside air inlet that takes in outside air and the air volume of the outside air can be changed.

The first acquisition unit 20 acquires a predicted temperature of the outside air. This predicted temperature may be a predicted temperature in the location or area where the air-conditioned space 3 exists. The predicted temperature acquired by the first acquisition unit 20 may be, for example, a predicted result of the air temperature for a predetermined period from the present. The predetermined period may be, for example, 24 hours or more. It is preferable that this predetermined period includes a time period in which the temperature is suitable for taking into the air-conditioned space 3. It is preferable that the predicted temperature of the outside air acquired by the first acquisition unit 20 is one that shows the future change in the temperature of the outside air over time, for example, as shown in FIG. 4. The predicted temperature of the outside air may be a predicted temperature of the outside air for each predetermined time, for example, every hour. The first acquisition unit 20 may acquire the predicted temperature of the outside air from, for example, the Japan Meteorological Agency or a private company that provides weather information. As an example, the first acquisition unit 20 may acquire the predicted temperature of the outside air in the location or area where the air-conditioned space 3 exists via a communication line such as the Internet. As another example, the first acquisition unit 20 may acquire the predicted outdoor temperature by predicting the outdoor temperature at the location where the air-conditioned space 3 is located using meteorological information such as the past outdoor temperature at the location where the air-conditioned space 3 is located and meteorological information such as future weather in the area where the air-conditioned space 3 is located.

The second acquisition unit 30 acquires the current temperature of the outside air at each of the multiple outside air inlets 51-53. The second acquisition unit 30 may, for example, acquire the current temperature of the outside air measured by the temperature sensors 31-33 arranged at each of the multiple outside air inlets 51-53 from the temperature sensors 31-33. The acquisition of this current temperature may, for example, be reception of the current temperature transmitted from the temperature sensors 31-33 via a wired or wireless communication line. Note that, as an example, the second acquisition unit 30 may have the temperature sensors 31-33. In this case, the acquisition of the current temperature by the second acquisition unit 30 may be a measurement of the current temperature.

It is preferable that the temperature sensors 31-33 measure the temperature of the outside air near the outside air inlets 51-53. For example, the temperature sensors 31-33 may be disposed inside the ducts 14b-14d near the outside air inlets 51-53, or may be disposed outside the ducts 14b-14d near the outside air inlets 51-53.

The control unit 40 uses the predicted outside air temperature acquired by the first acquisition unit 20 to control the timing of introducing outside air into the air-conditioned space 3 by the air-conditioning device 10. Based on the predicted outside air temperature, the control unit 40 can identify the time when the outside air has the most favorable temperature to introduce into the air-conditioned space 3. Then, based on the identification result, the control unit 40 may control the air-conditioning device 10 so that the outside air of the favorable temperature is introduced into the air-conditioned space 3.

The control unit 40 may control the air conditioner 10 so that the outdoor air with the smallest heat load on the air-conditioned space 3 is introduced into the air-conditioned space 3. The outdoor air with the smallest heat load on the air-conditioned space 3 may be considered to be the outdoor air that can minimize the heat load on the air-conditioned space 3 when introduced into the air-conditioned space 3. More specifically, the control unit 40 may control the air conditioner 10 so that the lowest temperature outdoor air is introduced into the air-conditioned space 3 when cooling is performed on the air-conditioned space 3, and control the air conditioner 10 so that the highest temperature outdoor air is introduced into the air-conditioned space 3 when heating is performed on the air-conditioned space 3. The case where cooling is performed on the air-conditioned space 3 may be a season in which cooling is performed on the air-conditioned space 3. Therefore, when the control unit 40 controls the air conditioner 10 to introduce outdoor air, the air conditioner 10 does not necessarily adjust the temperature of the air. The same applies to the case where heating is performed on the air-conditioned space 3.

Controlling the air conditioner 10 so that the coldest outside air is introduced into the air-conditioned space 3 may mean controlling the air conditioner 10 so that the outside air during the time period with the coldest predicted temperature is introduced into the air-conditioned space 3. Note that since this introduction of outside air is based on the predicted temperature, it is possible that the lowest temperature outside air is not actually introduced into the air-conditioned space 3, but it is considered that at least outside air close to the lowest temperature can be introduced into the air-conditioned space 3. The same applies when controlling the air conditioner 10 so that the warmest outside air is introduced into the air-conditioned space 3.

More specifically, when the acquired predicted temperature of the outside air is that shown in FIG. 4 and the air-conditioned space 3 is being cooled, the control unit 40 identifies the time T1 at which the predicted temperature is the lowest. Then, when the identified time T1 is reached, the control unit 40 may control the air conditioner 10 so that outside air is introduced into the air-conditioned space 3. Also, when the acquired predicted temperature of the outside air is that shown in FIG. 4 and the air-conditioned space 3 is being heated, the control unit 40 identifies the time T2 at which the predicted temperature is the highest. Then, when the identified time T2 is reached, the control unit 40 may control the air conditioner 10 so that outside air is introduced into the air-conditioned space 3.

In addition, the control unit 40 may control the air conditioner 10 so that, when the air conditioner 10 introduces the outside air into the air-conditioned space 3, the outside air is introduced into the air-conditioned space 3 from an outside air inlet having the smallest heat load of the outside air on the air-conditioned space 3, using the current temperature of the outside air acquired by the second acquisition unit 30. More specifically, the control unit 40 may, for example, when introducing the outside air into the air-conditioned space 3, identify an outside air inlet having the most suitable temperature of the outside air among the multiple outside air inlets 51 to 53, and control the air conditioner 10 so that the outside air is introduced into the air-conditioned space 3 from the identified outside air inlet. For example, when cooling is performed on the air-conditioned space 3, the control unit 40 may control the air conditioner 10 so that, when the air conditioner 10 introduces the outside air into the air-conditioned space 3, the outside air is introduced into the air-conditioned space 3 from an outside air inlet having the lowest current temperature of the outside air acquired by the second acquisition unit 30. Furthermore, for example, when heating is performed on the air-conditioned space 3, the control unit 40 may control the air-conditioning unit 10 so that when the air-conditioning unit 10 introduces outside air into the air-conditioned space 3, the outside air taken in from the outside air inlet having the highest current temperature of the outside air acquired by the second acquisition unit 30 is introduced into the air-conditioned space 3.

More specifically, when cooling is performed on the air-conditioned space 3, and the current outside air temperatures at the outside air inlets 51 to 53 acquired when the outside air is introduced into the air-conditioned space 3 are 21°C, 22°C, and 23°C, respectively, the outside air inlet 51 with the lowest outside air temperature may be selected as the outside air inlet for actually taking in the outside air, and the air conditioner 10 may be controlled so that the outside air is introduced from the selected outside air inlet 51. In this case, for example, the damper 51b may be opened and the dampers 51c and 51d may be closed, so that the outside air is introduced only from the outside air inlet 51.

By providing multiple outside air inlets 51-53 at different positions, it is possible that the outside air temperature at each of the outside air inlets 51-53 may differ. Therefore, by introducing outside air into the air-conditioned space 3 from the outside air inlet with the most suitable outside air temperature, it is possible to introduce outside air that is more suitable for air conditioning into the air-conditioned space 3, thereby further promoting energy conservation.

When outside air is being introduced into the air-conditioned space 3 as described above, for example, the damper 15a of the return air duct 14a may be closed and the damper 15e of the exhaust air duct 14e may be open. In this way, the air in the air-conditioned space 3 can be efficiently replaced with outside air. Also, when outside air is being introduced into the air-conditioned space 3, for example, the air volumes of the fans 11 and 12 may be approximately the same.

When outdoor air is introduced into the air-conditioned space 3 as described above, it is usually preferable that the proportion of outdoor air introduced into the air-conditioned space 3 is greater. For example, it is preferable that 30% or more of the volume of the air-conditioned space 3 is replaced with outdoor air, more preferable that 50% or more is replaced with outdoor air, even more preferable that 70% or more is replaced with outdoor air, and even more preferable that 90% or more is replaced with outdoor air.

On the other hand, when the daily range of the predicted temperature, i.e., the difference between the maximum and minimum temperatures in a day, is small, there is little benefit to introducing outside air into the air-conditioned space 3 all at once at a specific time. Therefore, the control unit 40 may control the air conditioning device 10 so that the greater the daily range of the predicted temperature acquired by the first acquisition unit 20, the greater the amount of outside air introduced into the air-conditioned space 3 at the time of introducing the outside air. In this case, the smaller the daily range of the predicted temperature acquired by the first acquisition unit 20, the less outside air will be introduced into the air-conditioned space 3 at the time of introducing the outside air.

The daily range of the predicted temperature may be, for example, the value obtained by subtracting the minimum temperature H1 from the maximum temperature H2 when the predicted temperature is as shown in FIG. 4. The daily range is usually a positive real number. The control unit 40 may, for example, calculate the daily range using the predicted temperature acquired by the first acquisition unit 20, and use information that associates the daily range with the amount of outdoor air introduced into the air-conditioned space 3 to identify the amount of outdoor air introduced that corresponds to the calculated daily range, and control the air conditioner 10 so that outdoor air corresponding to the identified amount is introduced into the air-conditioned space 3. The information that associates the daily range with the amount of outdoor air introduced into the air-conditioned space 3 may be, for example, a table that associates the two, or a function for calculating the amount of outdoor air introduced from the daily range.

Next, the operation of the air conditioning system 1 will be described with reference to the flowchart of FIG.
(Step S101) The control unit 40 judges whether or not to perform processing for determining the time to introduce outside air. If the processing for determining the time to introduce outside air is to be performed, the process proceeds to step S102, and if not, the process proceeds to step S104. The control unit 40 may, for example, periodically judge to perform processing for determining the time to introduce outside air. As an example, the control unit 40 may judge to perform processing for determining the time to introduce outside air at a predetermined time (for example, 12:00 a.m. or 2:00 a.m.) every day.

(Step S102) The first acquisition unit 20 acquires the predicted outside air temperature.

(Step S103) The control unit 40 uses the predicted outside air temperature acquired in step S102 to determine the time to introduce outside air. For example, in the cooling season, the time period when the predicted outside air temperature is the lowest may be determined as the time to introduce outside air, and in the heating season, the time period when the predicted outside air temperature is the highest may be determined as the time to introduce outside air. Then, the process returns to step S101. Note that the result of the determination of the time to introduce outside air may be shown as a period from the determination point, such as "three hours later," or may be shown as a time, such as "5:00 a.m." In the former case, for example, a timer may start timing from the determination point.

(Step S104) The control unit 40 determines whether it is time to introduce outside air as determined in step S103. If it is time to introduce outside air, proceed to step S105; if not, return to step S101. For example, if the determined result of the time to introduce outside air is a period from the determined time, such as "three hours later," and a timer has been measuring time since the determined time, the control unit 40 may determine that it is time to introduce outside air when the timer value reaches the determined result. Also, for example, if the determined result of the time to introduce outside air is a time, such as "5:00 a.m.", the control unit 40 may determine that it is time to introduce outside air when the time on a clock unit (not shown) reaches the determined result.

(Step S105) The second acquisition unit 30 acquires the current temperature of the outside air at each of the multiple outside air inlets 51 to 53.

(Step S106) The control unit 40 determines the outdoor air inlet corresponding to the most suitable temperature among the current temperatures acquired in step S105 as the outdoor air inlet to be used for introducing outdoor air. For example, in the cooling season, the outdoor air inlet corresponding to the lowest outdoor air temperature may be determined as the outdoor air inlet to be used for introducing outdoor air, and in the heating season, the outdoor air inlet corresponding to the highest outdoor air temperature may be determined as the outdoor air inlet to be used for introducing outdoor air.

(Step S107) The control unit 40 controls the air conditioner 10 so that outside air is introduced into the air-conditioned space 3 from the outside air inlet determined in step S106. Through this control, for example, a predetermined volume of outside air may be introduced into the air-conditioned space 3. Then, the process returns to step S101.

Although not included in the flowchart of FIG. 5, the temperature of the air supplied to the air-conditioned space 3 may be adjusted by the air conditioner 10 as appropriate. This temperature adjustment may be performed so that the temperature of the air in the air-conditioned space 3 is adjusted to a desired temperature. The air temperature adjustment may be performed, for example, simultaneously with the introduction of outside air, or may be performed separately from the introduction of outside air. Also, the order of the processing in the flowchart of FIG. 5 is one example, and the order of each step may be changed as long as similar results are obtained. Also, in the flowchart of FIG. 5, the processing may end due to an interruption such as power off or end of processing.

Next, the operation of the air conditioning system 1 according to this embodiment will be described using a specific example. Note that this specific example will mainly describe control during the season when cooling is performed in the air-conditioned space 3.

First, at midnight, the control unit 40 determines that a process for determining the timing of introducing outside air is to be performed, and transmits an instruction to the first acquisition unit 20 to acquire the predicted outside air temperature (step S101). Upon receiving the instruction, the first acquisition unit 20 accesses a server that provides meteorological information via the Internet, acquires from the server the predicted temperature, which is the predicted result of the air temperature for one day corresponding to the area in which the air-conditioned space 3 is located, and transmits the predicted temperature to the control unit 40 (step S102). The predicted temperature is assumed to be, for example, the one shown in FIG. 4.

When the predicted temperature is received, the control unit 40 determines the time T1 of the lowest temperature as the time to introduce outside air (step S103). This time T1 may be, for example, 5:00 a.m. The control unit 40 may, for example, store the time to introduce outside air, "5:00 a.m." in a memory unit or the like.

After that, at 5:00 a.m., when it is time to introduce outside air, the control unit 40 determines that outside air should be introduced into the air-conditioned space 3, and instructs the second acquisition unit 30 to acquire the current temperature at each of the multiple outside air inlets 51-53 (step S104). Upon receiving this instruction, the second acquisition unit 30 acquires the current outside air temperatures at the multiple outside air inlets 51-53 from the temperature sensors 31-33 arranged at each of the multiple outside air inlets 51-53, respectively, and passes them to the control unit 40 (step S105). Let us assume that the current temperatures acquired by the temperature sensors 31-33 are 21°C, 22°C, and 23°C, respectively.

When the control unit 40 receives the current temperature, it determines the outdoor air inlet 51 corresponding to 21°C, which is the lowest temperature among the received temperatures, as the outdoor air inlet to be used for introducing outdoor air (step S106), and the control unit 40 controls the air conditioner 10 so that outdoor air is introduced into the air-conditioned space 3 from the outdoor air inlet 51 (step S107). It is assumed that the temperature of the air supplied to the air-conditioned space 3 has not been adjusted at this point. Then, the control unit 40 controls the dampers 15a, 15c, and 15d to be closed and the dampers 15b and 15e to be opened. In addition, the blowers 11 and 12 are operated so that the outdoor air OA1 from the outdoor air inlet 51 is introduced into the air-conditioned space 3 and all the return air from the air-conditioned space 3 is discharged. This introduction of outdoor air may be continued, for example, until a predetermined volume of outdoor air is introduced into the air-conditioned space 3.

As described above, according to the air conditioning system 1 of this embodiment, it is possible to introduce outside air at an optimal temperature into the air-conditioned space 3. As a result, air conditioning can be performed more efficiently. For example, the energy consumption of the heat source device 9 when air-conditioning the air-conditioned space 3 can be further reduced in response to the introduction of the outside air, and the effect of energy saving can be further improved. In addition, when air conditioning such as cooling is performed in the air-conditioned space 3, it is usually necessary to introduce a certain amount of outside air into the air-conditioned space 3 for ventilation even if the temperature of the outside air is not suitable for air conditioning, and as a result, there is a problem that the efficiency of the air conditioning decreases. On the other hand, for example, in the season when air conditioning is performed, by introducing a large amount of outside air with the lowest temperature in the early morning into the air-conditioned space 3 in advance, the amount of outside air introduced can be reduced when air-conditioning is performed during the day. In other words, by introducing outside air with an optimal temperature, the amount of ventilation during normal air conditioning can be reduced, and the efficiency of air conditioning can be improved accordingly.

In addition, by introducing outside air from one of the multiple outside air inlets that has the most suitable current temperature, energy savings can be further promoted. Also, for example, introducing more outside air when the daily temperature difference is small would cause the fans 11 and 12 to operate unnecessarily, which would result in going against energy savings; however, by setting the amount of outside air introduced to be greater the greater the daily temperature difference in the predicted temperature, such a situation can be prevented from occurring.

In this embodiment, the case where the outdoor air inlet through which the outdoor air is introduced is determined using the current temperature of the outdoor air at each of the multiple outdoor air inlets 51-53 has been mainly described, but this is not necessarily the case. The outdoor air inlet through which the outdoor air is introduced may be determined using the current specific enthalpy of the outdoor air at each of the multiple outdoor air inlets 51-53. In this case, the second acquisition unit 30 may acquire the current specific enthalpy of the outdoor air at each of the multiple outdoor air inlets 51-53 instead of the current temperature of the outdoor air at each of the multiple outdoor air inlets 51-53. The specific enthalpy can be calculated using, for example, two values from among the dry bulb temperature, wet bulb temperature, relative humidity, and absolute humidity. Therefore, the second acquisition unit 30 may acquire current values measured by two types of sensors (e.g., a temperature sensor for measuring dry-bulb temperature and a humidity sensor for measuring relative humidity) arranged at each of the plurality of outdoor air inlets 51 to 53 from the two types of sensors, and calculate the current specific enthalpy using the two acquired current values. The measurement of the current value by the two types of sensors is preferably performed near the outdoor air inlets 51 to 53, similar to the measurement of the current temperature by the temperature sensors 31 to 33. In addition, the second acquisition unit 30 may acquire the current specific enthalpy calculated using the current values measured by the two types of sensors arranged at each of the plurality of outdoor air inlets 51 to 53 from a specific enthalpy acquisition device that performed the calculation. The acquisition of the two current values from the two types of sensors by the second acquisition unit 30 and the acquisition of the current specific enthalpy from the specific enthalpy acquisition device by the second acquisition unit 30 may be, for example, reception of transmitted information via a wired or wireless communication line. As an example, the second acquisition unit 30 may have two types of sensors arranged at each of the multiple outside air inlets 51-53. In this case, the second acquisition unit 30 may acquire the current specific enthalpy by measuring the current value using the two types of sensors and calculating the specific enthalpy using the measurement results. Also, even if the outside air inlet that introduces the outside air is determined using the current specific enthalpy of the outside air, it is preferable that the multiple outside air inlets 51-53 are provided so that the specific enthalpy of the outside air at each position is different.

When the second acquisition unit 30 acquires the current specific enthalpy of the outside air at each of the multiple outside air inlets 51 to 53, the control unit 40 may use the current specific enthalpy of the outside air acquired by the second acquisition unit 30 to control the air conditioning unit 10 so that, when the outside air is introduced into the air-conditioned space 3 by the air conditioning unit 10, the outside air taken in from the outside air inlet which has the smallest thermal load on the air-conditioned space 3 is introduced into the air-conditioned space 3. More specifically, the control unit 40 may control the air conditioner 10 so that, when cooling is performed on the air-conditioned space 3, the air conditioner 10 introduces the outside air taken in through the outside air inlet having the lowest current specific enthalpy of the outside air acquired by the second acquisition unit 30 into the air-conditioned space 3, and when heating is performed on the air-conditioned space 3, the control unit 40 controls the air conditioner 10 so that the outside air taken in through the outside air inlet having the highest current specific enthalpy of the outside air acquired by the second acquisition unit 30 into the air-conditioned space 3. In this way, when cooling is performed, the outside air with the lowest specific enthalpy, for example, the outside air with a low temperature and humidity, can be introduced into the air-conditioned space 3, and when heating is performed, the outside air with the highest specific enthalpy, for example, the outside air with a high temperature and humidity, can be introduced into the air-conditioned space 3.

In addition, in this embodiment, the air conditioner 10 can introduce the outside air taken in from multiple outside air inlets 51-53 into the air-conditioned space 3, and among the multiple outside air inlets 51-53, the case where the outside air is taken in from an outside air inlet having an optimal current temperature and current specific enthalpy of the outside air has been mainly described, but this is not necessarily the case. For example, even if the air conditioner 10 can introduce the outside air taken in from multiple outside air inlets 51-53 into the air-conditioned space 3, the air conditioner 10 may take in outside air from each of the outside air inlets 51-53. Also, for example, the air conditioner 10 may take in outside air from only one outside air inlet. In these cases, the air conditioning system 1 may not be equipped with, for example, the second acquisition unit 30.

In addition, in this embodiment, the case where the timing of introducing the outside air is controlled using the predicted temperature of the outside air has been mainly described, but this is not necessary. The timing of introducing the outside air may be controlled using the predicted enthalpy of the outside air. In this case, the first acquisition unit 20 may acquire the predicted specific enthalpy instead of the predicted temperature. As described above, the specific enthalpy can be calculated using two values, for example, the dry-bulb temperature, the wet-bulb temperature, the relative humidity, and the absolute humidity. Therefore, the first acquisition unit 20 may acquire two values, for example, the predicted dry-bulb temperature, the predicted wet-bulb temperature, the predicted relative humidity, and the predicted absolute humidity, and calculate the predicted specific enthalpy using the two acquired values. Alternatively, the first acquisition unit 20 may acquire the predicted specific enthalpy of the outside air from, for example, the Japan Meteorological Agency or a private company that provides weather information. Note that the acquisition of the predicted specific enthalpy by the first acquisition unit 20 may be performed in the same manner as described above, except that the acquisition target has changed from the predicted temperature to the predicted specific enthalpy.

Even when the predicted specific enthalpy is acquired by the first acquisition unit 20, the control unit 40 may control the air conditioner 10 so that the outdoor air with the smallest heat load on the air-conditioned space 3 is introduced into the air-conditioned space 3. More specifically, the control unit 40 may control the air conditioner 10 so that, for example, when cooling the air-conditioned space 3, the outdoor air with the lowest specific enthalpy is introduced into the air-conditioned space 3, and when heating the air conditioner 10, the control unit 40 may control the air conditioner 10 so that the outdoor air with the highest specific enthalpy is introduced into the air-conditioned space 3.

In addition, when the predicted specific enthalpy is acquired, the control unit 40 may control the air conditioner 10 so that, for example, the greater the daily difference in the predicted specific enthalpy acquired by the first acquisition unit 20, the greater the amount of outside air introduced into the air-conditioned space 3 at the time of introducing the outside air. This control is similar to the control in which the greater the daily difference in the predicted temperature, the greater the amount of outside air introduced into the air-conditioned space 3 at the time of introducing the outside air, except that the predicted temperature becomes the predicted specific enthalpy, and a detailed description thereof will be omitted.

In addition, in this embodiment, the introduction of outside air into the air-conditioned space 3 may be controlled according to the temperature of the air-conditioned space 3 after the introduction of the outside air. In this case, the air-conditioning system 1 may further include a third acquisition unit 50 that acquires the temperature of the air-conditioned space 3, for example, as shown in FIG. 6. The third acquisition unit 50 may acquire the temperature of the air-conditioned space 3 measured by the temperature sensor 51 arranged in the air-conditioned space 3 from the temperature sensor 51. The acquisition of the current temperature may be, for example, reception of the current temperature transmitted from the temperature sensor 51 via a wired or wireless communication line. As an example, the third acquisition unit 50 may have a temperature sensor 51. In this case, the acquisition of the temperature of the air-conditioned space 3 by the third acquisition unit 50 may be measurement of the temperature of the air-conditioned space 3. In addition, the temperature of the air-conditioned space 3 acquired by the third acquisition unit 50 may be, for example, a representative value of the temperatures of the air-conditioned space 3 measured at multiple positions. The representative value may be, for example, an average value, a median value, a maximum value, a minimum value, or the like.

When the temperature of the air-conditioned space 3 is acquired by the third acquisition unit 50, the control unit 40 may control the air conditioner 10 so that outside air is introduced into the air-conditioned space 3 within a range in which the acquired temperature does not exceed a target value in the temperature adjustment direction. The temperature adjustment direction may be the temperature adjustment direction in air conditioning, and may be, for example, a direction in which the temperature decreases when cooling is performed in the air-conditioned space 3, and may be a direction in which the temperature increases when heating is performed in the air-conditioned space 3. The target value may be, for example, the same as the target temperature of the air conditioner 10, or may be different. For example, when cooling is performed, when the temperature of the outside air is 20°C and the target value in the temperature adjustment direction of the air-conditioned space 3 is set to 23°C, the control unit 40 may control the introduction of outside air by the air conditioner 10 so that the temperature of the air-conditioned space 3 is 23°C or higher. More specifically, when the temperature acquired by the third acquisition unit 50 becomes 23°C, the control unit 40 may stop the introduction of outside air into the air-conditioned space 3. This makes it possible to avoid introducing too much outside air into the air-conditioned space 3, and reduces the energy required to introduce the outside air.

In this case, control may be performed using specific enthalpy instead of temperature. When control using specific enthalpy is performed, the third acquisition unit 50 may acquire the specific enthalpy of the air-conditioned space 3. This acquisition of specific enthalpy may be performed, for example, in the same manner as the acquisition of specific enthalpy by the second acquisition unit 20. Furthermore, when specific enthalpy is acquired, the control unit 40 may control the air conditioner 10 so that outside air is introduced into the air-conditioned space 3 within a range in which the acquired specific enthalpy does not exceed a target value in the direction of specific enthalpy adjustment. This control is similar to the control of the introduction of outside air using the temperature of the air-conditioned space 3, except that the temperature becomes the specific enthalpy, and a detailed description thereof will be omitted.

In addition, in this embodiment, the air conditioner 10 is mainly used to adjust the temperature of the air supplied to the air-conditioned space 3, but this is not necessarily the case. The air conditioner 10 is used to introduce outside air into the air-conditioned space 3, and the temperature of the air supplied to the air-conditioned space 3 may be adjusted by another air conditioner. In this case, the air conditioner 10 does not need to be equipped with a coil 13.

In addition, in the above embodiments, each process or function may be realized by centralized processing in a single device or a single system, or may be realized by distributed processing in multiple devices or multiple systems.

In addition, in the above embodiment, when two or more components included in the air conditioning system 1 have a communication device, an input device, etc., the two or more components may physically have a single device, or may have separate devices.

In the above embodiment, each component may be configured by dedicated hardware, or a component that can be realized by software may be realized by executing a program. For example, a program execution unit such as a CPU reads and executes a software program recorded on a recording medium such as a hard disk or semiconductor memory, thereby realizing a component that can be realized by software. During execution, the program execution unit may execute the program while accessing the storage unit or recording medium. The program may be executed by being downloaded from a server or the like, or may be executed by reading a program recorded on a predetermined recording medium (e.g., an optical disk, a magnetic disk, a semiconductor memory, etc.). The program may be used as a program that constitutes a program product. The computer that executes the program may be a single computer or a plurality of computers. In other words, centralized processing or distributed processing may be performed.

The above embodiments are merely examples for specifically implementing the present invention, and are not intended to limit the technical scope of the present invention. The technical scope of the present invention is indicated by the claims, not by the description of the embodiments, and is intended to include modifications within the literal scope of the claims and within the scope of equivalent meanings.

Reference Signs List 1 Air conditioning system 3 Air-conditioned space 10 Air conditioning device 20 First acquisition unit 30 Second acquisition unit 40 Control unit 51 to 53 Outside air intake port

Claims (4)

An air conditioning device that introduces outside air into the air-conditioned space;
A first acquisition unit that acquires a predicted temperature or a predicted specific enthalpy of outside air;
a control unit that controls a timing of introduction of outside air into the air-conditioned space by the air-conditioning device using the predicted temperature or predicted specific enthalpy of the outside air acquired by the first acquisition unit,
The control unit controls the air conditioning device so that outside air with the smallest thermal load on the air-conditioned space is introduced into the air-conditioned space , and also controls the air conditioning device so that the amount of outside air introduced into the air-conditioned space during the outside air introduction period increases the greater the daily difference in predicted temperature or predicted specific enthalpy acquired by the first acquisition unit . The air conditioner is capable of introducing outside air taken in through a plurality of outside air inlets located at different positions into the air-conditioned space,
A second acquisition unit that acquires a current temperature or a current specific enthalpy of the outside air at each of the plurality of outside air inlets,
The air conditioning system of claim 1, wherein the control unit controls the air conditioning unit so that, when outside air is introduced into the air-conditioned space by the air conditioning unit, the outside air is introduced into the air-conditioned space from an outside air inlet that has the smallest heat load on the air-conditioned space, using the current temperature or current specific enthalpy of the outside air acquired by the second acquisition unit. A third acquisition unit that acquires a temperature or a specific enthalpy of the air-conditioned space,
The air conditioning system according to claim 1 , wherein the control unit controls the air conditioning device so that outside air is introduced into the air-conditioned space within a range in which the temperature or specific enthalpy acquired by the third acquisition unit does not exceed a target value in a direction in which the temperature or specific enthalpy is adjusted. A method for controlling an air conditioner that introduces outside air into an air-conditioned space, comprising:
obtaining a predicted temperature or a predicted specific enthalpy of the outside air;
and controlling a timing of introduction of the outside air into the air-conditioned space by the air-conditioning device using the obtained predicted temperature or predicted specific enthalpy of the outside air;
a step of controlling the timing of introducing outside air, the step of controlling the air conditioning device so that the outside air with the smallest thermal load on the air-conditioned space is introduced into the air-conditioned space, and the control of the air conditioning device so that the amount of outside air introduced into the air-conditioned space at the timing of introducing outside air increases the greater the daily difference in the obtained predicted temperature or predicted specific enthalpy .

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