JP2012063117A - Air conditioning system - Google Patents

Abstract

An object of the present invention is to provide an air conditioning system that can save energy while introducing an appropriate amount of outside air into the room.
An air conditioning system 1 that performs air conditioning processing of an indoor task load and an ambient load by an all-air method, and is an air conditioner that performs air conditioning processing of the task load, and a plurality of VAV units 3c corresponding to the indoor task load. The VAV air conditioner 3 that adjusts the air flow for each VAV unit 3c and supplies air to the task load zone T, and the air conditioner that air-conditions the ambient load, air-conditions the outside air taken from outside And an ambient air conditioner 4 for supplying air to the zone A of the ambient load, and when the low load condition of the air conditioning load is satisfied, the operation of the VAV air conditioner 3 is stopped, and the VAV air conditioner 3, the supply air temperature of the ambient air conditioner 4 is controlled based on the set temperature for each of the three VAV units 3 c and the room detected temperature.
[Selection] Figure 1

Description

  The present invention relates to an air conditioning system that performs an air conditioning process on indoor task loads and ambient loads using an all-air method.

  In office buildings (especially business buildings (tent buildings)), air-conditioning systems using all-air systems are often adopted from the viewpoints of variability (followability to partitions, etc.), reliability (water damage risk, etc.), and maintainability. . As an all-air type air conditioning system, there is generally a single duct air conditioning system mainly composed of ducts. In the single duct air conditioning system, air that has been air-conditioned by an air conditioner provided in an air conditioning machine room is sent to each room using a duct.

  FIG. 6 shows a single-duct VAV [Variable Air Volume] air-conditioning system that is currently most adopted as an air-conditioning system for large business buildings as an example of the single-duct air-conditioning system. In this single duct VAV air conditioning system 100, outside air OA and ambient air RA from the office room S1 are taken into the air conditioner body 101 of the air conditioning machine room S3. In the air conditioner body 101, the air taken in by the filter 103 is purified, and the purified air is passed through the cold water coil 104 and the hot water coil 105 to produce cold air or hot air, and is humidified through the humidifier 106 as necessary. , And sent to the duct 108 by the fan 107. The air-conditioned air flowing through the duct 108 is adjusted in air volume by the VAV units 109,... For each zone in the office room S1, and the supply air SA is blown out to each zone in the office room S1. The In addition, in the case of the single duct VAV air conditioning system 100, the air volume in each zone can be controlled by the VAV units 109,... Arranged in a distributed manner, so that the followability to the partition is excellent and air is used as a carrier heat medium. There is no risk of water damage.

In recent years, from the viewpoint of energy saving and CO ₂ saving, there is a demand for energy saving in an air conditioning system. However, in the case of a conventional single-duct air conditioning system air conditioning system, a fan (blower) for transporting air is used, and thus a limit is pointed out in terms of air transport power. In the case of the single duct VAV air conditioning system 100 described above, when the fan 107 is stopped, the outside air OA cannot be taken in and the CO ₂ concentration becomes high. Therefore, it is necessary to keep the fan 107 in operation during the operation time. It always consumes power to operate. Therefore, even when the air conditioning load in the office room S1 is low, it is necessary to keep the power of the fan 107 above a certain level.

  Therefore, various air conditioning systems for energy saving have been proposed. For example, Patent Document 1 includes a task air conditioner that air-conditions an indoor task area, an ambient air conditioner that air-conditions the ambient area, and a personal air outlet for supplying air to the perimeter area by the task air conditioner. In the energy saving mode, it is described that the ambient air conditioner is the main operating machine and the task air conditioner is the chasing operation.

  In addition, there is a water system as an energy-saving air conditioning system centering on application to a head office building and the like, not a tenant building, and there is a radiation air conditioning system as a water system. In the radiant air conditioning system, a cold water pipe through which cold water flows is stretched over a steel panel on the ceiling, and the indoor air is slowly cooled by the radiation effect from the steel panel cooled by the cold water pipe. In the case of a radiant air conditioning system, the conveyance power is small, but there is a risk of water loss in the office because the cold water pipe is stretched around the ceiling of the office. Therefore, it is not suitable for tenant buildings that require variability, reliability, and maintainability.

JP 2007-333355 A JP-A-5-256491 Japanese Patent Laid-Open No. 3-164641

  In air conditioning, it is necessary to ensure the introduction of the required amount of outside air into the room. However, if the air conveyance power is reduced to save energy, the amount of outside air introduced may be insufficient. In the case of the air-conditioning system of Patent Document 1 described above, introduction of outside air into the room is not described, and even how to ensure introduction of a necessary amount of outside air in the energy saving mode is described. Absent.

  Then, this invention makes it a subject to provide the air-conditioning system which can aim at energy saving, introduce | transducing an appropriate amount of outside air indoors.

  An air conditioning system according to the present invention is an air conditioning system that performs air conditioning processing of an indoor task load and an ambient load by an all-air method, and is an air conditioner that performs air conditioning processing of a task load. A VAV air conditioner that has VAV units and supplies air to the task load zone by adjusting the air flow rate for each VAV unit, and an air conditioner that air-conditions ambient loads. And an ambient air conditioner for supplying air to the ambient load zone.

  This air conditioning system includes a VAV air conditioner that mainly air-conditions indoor task loads and an ambient air conditioner that mainly air-conditions indoor ambient loads. The task load is a local load that is unevenly distributed in the room due to indoor workers or equipment. The ambient load is a base load in the room other than the task load. The VAV air conditioner has a plurality of VAV units corresponding to task loads that are unevenly distributed in the room, and the air volume is adjusted for each VAV unit to mainly supply air to the task load zone. An ambient air conditioner takes outside air, air-conditions the outside air, and supplies air mainly to the ambient load zone in the room. Since this air conditioning system is equipped with a VAV air conditioner and an ambient air conditioner, the ambient air conditioner having a function of introducing outside air into the room is prioritized so that the ambient air conditioner can always provide an appropriate amount in the room. While introducing the outside air, it is possible to significantly reduce the air conveyance power of the entire system and save energy.

In the air conditioning system of the present invention, it is preferable to stop the operation of the VAV air conditioner when the low load condition of the air conditioning load is satisfied. In this air conditioning system, when the low load condition of the air conditioning load is satisfied, the operation of the VAV air conditioner for air conditioning the task load is stopped. Power can be further reduced. Even if the VAV air conditioner is stopped, the ambient external air conditioner having the outside air introduction function is in operation, so that the indoor CO ₂ concentration does not increase.

  In the air conditioning system of the present invention, the low load condition of the air conditioning load is that the coil valve of the VAV air conditioner is fully closed, the operating state of the fan is at the lower limit level, and there is no cooling request signal from the VAV unit. VAV air conditioner coil valve (for example, two-way valve) is fully closed (water flow to the coil is stopped) and fan (blower) operating status (for example, inverter frequency) is air-conditioned to the lower limit level (task load zone) No air supply is required) and there is no cooling request signal from the VAV unit. This is a state where there is no need for air conditioning load processing by the VAV air conditioner. Therefore, when this condition is satisfied, even if the VAV air conditioner is stopped, there is no problem with the indoor air conditioning load.

  In the air conditioning system of the present invention, it is preferable to control the supply air temperature of the ambient air conditioner based on the set temperature for each VAV unit of the VAV air conditioner and the detected room temperature. As described above, in the air conditioning system, the temperature load state of the entire room is controlled by controlling the air supply temperature of the ambient air conditioner based on the set temperature for each VAV unit corresponding to the task load unevenly distributed in the room and the detected room temperature. The ambient air conditioner supply air temperature can be set in accordance with the air supply temperature, and the optimum operation control can be performed so that the ambient air conditioner preferentially processes the air conditioning load according to the supply air temperature. As a result, according to the temperature load state of the whole room, it is possible to always demonstrate from the low capacity to the maximum capacity in the range of the air conditioning load processing capacity of the ambient air conditioner, and it is possible to stop the operation of the VAV air conditioner more effectively.

  In the air conditioning system of the present invention, the temperature difference between the set temperature and the room detected temperature is calculated for each VAV unit of the VAV air conditioner, the average temperature difference of the temperature differences for all the calculated VAV units is calculated, When the calculated average temperature difference is subtracted from the initial setting air temperature of the ambient air conditioner, and the temperature obtained by the subtraction is equal to or higher than the lower limit value (preset value) of the ambient air conditioner The temperature obtained by subtraction is used as the supply air temperature of the ambient air conditioner.If the temperature obtained by subtraction is less than the supply air temperature lower limit value, the supply air temperature lower limit value is set as the supply air temperature of the ambient air conditioner. And As a result, this air conditioning system preferentially uses the low capacity (at the initial supply air temperature) to the maximum capacity (at the lower supply air temperature) of the ambient air conditioner according to the air conditioning load state of the entire room. The optimal supply air temperature can be set.

  According to the present invention, since the VAV air conditioner and the ambient air conditioner are provided, the ambient air conditioner having the function of introducing the outside air is preferentially operated. While being introduced, it is possible to greatly reduce the air conveyance power of the entire system and save energy.

It is a block diagram of the air conditioning system which concerns on this Embodiment. It is a piping diagram of the cold water coil of the VAV air conditioner of FIG. It is a flowchart which shows the flow of VAV air conditioner stop control in the air conditioning system of FIG. It is a flowchart which shows the flow of VAV air conditioner return control in the air conditioning system of FIG. It is a flowchart which shows the flow of ambient outside air conditioner supply air temperature control in the air conditioning system of FIG. It is a block diagram of the conventional single duct VAV air conditioning system.

  Hereinafter, an embodiment of an air-conditioning system according to the present invention will be described with reference to the drawings. In addition, the same code | symbol is attached | subjected about the element which is the same or it corresponds in each figure, and the overlapping description is abbreviate | omitted.

  In the present embodiment, the present invention is applied to an all-air type air conditioning system of an office building (particularly a tenant building). The air conditioning system according to the present embodiment air-conditions the perimeter and the task load and the ambient load in the office room of the tenant building with different types of air conditioners.

  If the room is divided into spaces, there are perimeters and interiors. The perimeter is an indoor outer peripheral area (such as around a window in contact with the outside air), is an area that is greatly affected by the temperature of outside air and solar radiation, and has a large thermal fluctuation throughout the year. The interior is an area inside the room, and is less affected by outside air temperature and solar radiation, and is affected by people, lighting, equipment, and the like in the room. When the room is divided by load, there are task load and ambient load. The task load is a local load that is unevenly distributed in the room due to indoor workers or equipment. The ambient load is a base load in the room other than the task load.

  With reference to FIG.1 and FIG.2, the air conditioning system 1 which concerns on this Embodiment is demonstrated. FIG. 1 is a configuration diagram of an air conditioning system according to the present embodiment. FIG. 2 is a piping diagram of a cold water coil of the VAV air conditioner of FIG.

  The air conditioning system 1 individually loads the perimeter with a plurality of individually distributed packages 2,... Performs air conditioning with a VAV air conditioner 3 for task loads, and an ambient air conditioner for ambient loads. Air-conditioning treatment is performed at 4. In particular, the air conditioning system 1 uses the controller 5 to stop the VAV air conditioner 3 when the air conditioning load is low, and to supply the ambient air conditioner 4 in order to preferentially perform the air conditioning load with the ambient air conditioner 4. Perform air temperature control.

  The plurality of individually distributed packages 2,... Have a function of individually air-conditioning each zone of the perimeter P in the office room S1. The plurality of individually distributed packages 2,... Are distributed and arranged above the perimeter P in the ceiling back S2. The individual distributed package 2 is of a heat pump type and is like a business room air conditioner, in which an outdoor unit and an indoor unit are connected by a refrigerant pipe. The individual distributed package 2 individually controls according to the air conditioning load state of the zone to which the perimeter P is assigned, and performs air conditioning on the assigned zone individually. In each individual distributed package 2, the air RA is sucked from the suction port 2a of the zone to which the perimeter P is assigned, the sucked air is air-conditioned, and the conditioned air SA is sent from the outlet 2b to the zone to which the perimeter P is assigned. To blow out.

  The VAV air conditioner 3 has an air conditioning load processing function for task loads unevenly distributed in the office room S1. In the VAV air conditioner 3, the air conditioner main body 3a is provided in the air conditioning machine room S3 outside the office room S1, and a duct 3b and a plurality of VAV units 3c,. The air conditioner body 3a includes a filter 3d, a cold water coil 3e, a hot water coil 3f, a fan 3g, and the like. The duct 3b is supplied from the air conditioner main body 3a to the upper part of each task load zone T in the ceiling S2 in order to supply air to the task load zones T unevenly distributed in the office room S1. It is stretched around. The VAV unit 3c is provided for one zone of task load or a plurality of zones of task load, and is attached to the duct 3b.

  In the VAV air conditioner 3, the air RA flowing into the underfloor S4 from the floor suction ports 3h,... Is sent to the air conditioner body 3a through the duct 3i. In the air conditioner main body 3a, the taken-in air is purified by the filter 3d, and the purified air is passed through the cold water coil 3e and the hot water coil 3f to produce cold air or warm air, and sent to the duct 3b by the fan 3g.

  The cold water coil 3e and the hot water coil 3f are provided with a two-way valve 3j in the piping as shown in FIG. 2 (FIG. 2 shows an example of the cold water coil 3e, but the hot water coil 3f has the same configuration). The flow rate of cold water or hot water is adjusted according to the open / close state of the two-way valve 3j. The two-way valve 3j is controlled to open and close by the controller 5. When the two-way valve 3j is in the fully closed state, the water is not passed through the cold water coil 3e and the hot water coil 3f, and is in a low load state where cooling or heating is not required.

  The fan 3g is controlled by a motor (not shown) by an inverter (not shown) to adjust the amount of air sent to the duct 3b. The higher the frequency of the inverter, the higher the motor speed and the greater the amount of blown air. The frequency of the inverter is controlled by the controller 5. When the frequency of the inverter is a lower limit value (for example, 25 to 30 Hz), the air volume is minimized while the VAV air conditioner 3 is in operation, and a low load state in which cooling and heating are almost unnecessary with respect to the task load. When the operation of the VAV air conditioner 3 is stopped, the energization to the fan 3g is stopped and the power consumed by the fan 3g becomes zero.

  Each VAV unit 3c provided in the duct 3b includes a set temperature set by a person in each zone T of the task load for each VAV unit 3c and a temperature sensor provided for each VAV unit 3c by the VAV controller 3n built in the unit. The damper is controlled to open / close based on the detected temperature detected at 3k and the detected air volume detected by an air volume sensor (not shown), and the air flow rate to the task load zone T is adjusted according to the open / closed state of the damper. Information such as the set temperature and the detected temperature in each VAV unit 3c is transmitted to the controller 5, and the controller 5 uses the information to control opening and closing of the two-way valves 3j of the coils 3e and 3f in the VAV air conditioner 3. And the inverter of the fan 3g is controlled. When the damper of the VAV unit 3c is open, the controlled air volume of the air SA is blown out from the outlet 3m to the task load zone T. When the damper of the VAV unit 3c is working in the closing direction, the amount of blown air is reduced (0 when the damper is fully closed), and the cooling request (or heating request) is small.

  The ambient air conditioner 4 has an outside air introduction function to the office room S1, a base load processing function of the office room S1, and a humidity management function of the office room S1. In the ambient air conditioner 4, the air conditioner body 4a is provided in the air conditioning machine room S3, the duct 4b is disposed in the ceiling back S2, and the outside air duct 4c connected to the air conditioner body 4a is disposed. The external air conditioner body 4a includes a filter 4d, a cold water coil 4e, a hot water coil 4f, a humidifier 4g, a fan 4h, and the like. The duct 4b is stretched from the external air conditioner body 4a to a predetermined position in the ceiling back S2 so as to supply air to the ambient load zones A,... That are uniformly distributed to the office room S1. . The outside air duct 4c is a duct for taking in outside air OA, and is disposed between the outside air intake (not shown) of the building and the external air conditioner body 4a. Incidentally, a part of the air in the office room S1 is released to the outside through the exhaust duct 6 from the ceiling back S2.

  The ambient air conditioner 4 takes in the outside air OA from outside the building, and sends the taken outside air OA to the outside air conditioner main body 4a through the outside air duct 4c. In the external conditioner body 4a, the outside air OA taken in is purified by the filter 4d, and the purified air is passed through the cold water coil 4e and the hot water coil 4f to produce cold air or hot air, and if necessary, through the humidifier 4g. It is humidified and sent to the duct 4b by the fan 4h. Then, the air SA (outside air OA) guided by the duct 4b is blown out from the outlet 4i,... To the zone A of the ambient load.

  Since the cold water coil 4e, the hot water coil 4f, and the fan 4h are the same as the cold water coil 3e, the hot water coil 3f, and the fan 3g of the VAV air conditioner 3, the description thereof is omitted. However, when comparing the VAV air conditioner 3 and the ambient air conditioner 4, the VAV air conditioner 3 has a higher load processing capacity with respect to the air conditioning load of the entire room. Therefore, the cold water coil 4e, the hot water coil 4f, and the fan 4h are the cold water coil 3e, It is smaller than the hot water coil 3f and the fan 3g. Therefore, the fan 4h has less air conveyance power and less power consumption than the fan 3g. The humidifier 4g is controlled by the controller 5 and operates when the humidity in the office room S1 is low.

The ambient air conditioner 4 includes a representative indoor thermostat (not shown) in the office room S 1, and the set temperature and sensor detection temperature in the representative room are used for control by the controller 5. The ambient air conditioner 4 includes a humidity sensor (not shown) that detects the humidity in the office room S <b> 1, and the humidity detected by the sensor is used for control by the controller 5. Further, ambient outside conditioner 4 is provided with a CO ₂ concentration sensor for detecting the CO ₂ concentration in the office S1 (not shown), it is detected CO ₂ concentration by the sensor used for controlling the controller 5.

  The controller 5 is a controller that controls the VAV air conditioner 3 and the ambient air conditioner 4, and is provided in the air conditioning machine room S3. The controller 5 controls the operation of the VAV air conditioner 3 and the operation of the ambient air conditioner 4. In particular. The controller 5 preferentially processes the air conditioning load by the ambient air conditioner 4 and controls the VAV air conditioner 3 to follow only when the air conditioning load is large. Therefore, the controller 5 performs idling stop control for the VAV air conditioner 3 and supply air temperature control for the ambient air conditioner 4.

  The operation control of the VAV air conditioner 3 will be described. In the VAV air conditioner 3, the air conditioner main body 3a is controlled by the controller 5, and each VAV unit 3c is controlled by the built-in VAV controller 3n. The VAV controller 3n controls the opening / closing of the damper of the VAV unit 3c based on the set temperature of the VAV unit 3c and the sensor detection temperature. For example, the VAV unit 3c is controlled to open as the sensor detection temperature is higher than the set temperature. Thus, when the VAV unit 3c is opened, there is a cooling request (or heating request), and the information is transmitted to the controller 5 as a cooling request signal (or heating request signal). Further, the controller 5 controls the opening / closing of the two-way valve 3j of each coil 3e, 3f and the frequency of the inverter of the fan 3g based on the set temperature and sensor detection temperature of all the VAV units 3c. For example, as the sensor detection temperature is higher than the set temperature, the control is performed so that the two-way valve 3j is opened and the frequency of the inverter of the fan 3g is increased. The operation control of the VAV air conditioner 3 is an example, and other operation control may be used.

The operation control of the ambient air conditioner 4 will be described. The controller 5 based on the detection CO ₂ concentration of the set temperature and the sensor detection temperature and CO ₂ concentration sensor in a representative room thermostat ambient outside conditioner 4, so that the supply air temperature set by the supply air temperature control The opening and closing of the two-way valves of the coils 4e and 4f and the inverter frequency of the fan 4h are controlled. Further, the controller 5 controls the humidifier 4g based on the humidity detected by the humidity sensor. The operation control of the ambient air conditioner 4 is an example, and other operation control may be used.

  The idling stop control will be described. The controller 5 performs a VAV air conditioner stop control for automatically stopping the VAV air conditioner 3 having a large air conveyance power (that is, the power consumption of the fan 3g is large) when the air conditioning load is in a low load state. The VAV air conditioner return control for automatically returning the VAV air conditioner 3 that has been made is performed.

  The VAV air conditioner stop control of the idling stop control will be described along the flowchart of FIG. While the VAV air conditioner 3 is in operation, the VAV air conditioner stop control is performed. The controller 5 determines whether the two-way valve 3j of the cold water coil 3e of the VAV air conditioner 3 and the two-way valve 3j of the hot water coil 3f are both fully closed as the stop condition 1 (S10). When it is determined in S10 that at least one is not fully closed, the controller 5 returns to S10 and determines again after a predetermined time.

  When it is determined that both are fully closed in S10, the controller 5 determines whether the inverter frequency of the fan 3g of the VAV air conditioner 3 is the lower limit value as the stop condition 2 (S11). If it is determined in S11 that the inverter frequency is not the lower limit value, the controller 5 returns to S10 and determines again after a predetermined time.

  When it is determined in S11 that the inverter frequency is the lower limit value, the controller 5 determines whether there is no cooling request signal from all the VAV units 3c,... Of the VAV air conditioner 3 as the stop condition 3 (S12). ). If it is determined in S12 that there is a cooling request signal from the VAV unit 3c, the controller 5 returns to S10 and determines again after a predetermined time. Note that the heating request signal from the VAV units 3c,... May be determined, and it is determined whether both the cooling request signal and the heating request signal are present.

  When it is determined in S12 that there is no cooling request signal from all the VAV units 3c, the controller 5 determines whether or not the state where all the stop conditions 1 to 3 are satisfied continues for 10 minutes (S13). If it is determined in S13 that the operation has not been continued for 10 minutes, the controller 5 returns to S10 and determines again after a predetermined time. In the duration determination, the duration can be set to any time such as 5 minutes.

  When it determines with the state which satisfy | filled all the stop conditions 1-3 in S13 having continued for 10 minutes, the controller 5 stops the VAV air conditioner 3 (S14). In order to stop the VAV air conditioner 3, the controller 5 stops energizing the fan 3g (motor) and stops the fan 3g. Since both the cold water coil 3e and the two-way valve 3j of the hot water coil 3f are fully closed, the water flow to the cold water coil 3e and the hot water coil 3f is also stopped. By determining whether it has continued for a predetermined time, it is possible to reliably determine that the air conditioning load processing by the VAV air conditioner 3 is not required, and the VAV air conditioner 3 returns immediately after the automatic stop and stops. It is possible to prevent repeated return.

  Incidentally, the state where all the stop conditions 1 to 3 are satisfied is a state where the air conditioning load is a low load state and the air conditioning load process by the VAV air conditioner 3 is not required. At this time, the air conditioning load by the ambient air conditioner 4 is sufficient for the air conditioning load. While the fan 3g of the VAV air conditioner 3 is stopped, the power consumption in the VAV air conditioner 3 becomes zero.

  The VAV air conditioner return control of the idling stop control will be described along the flowchart of FIG. While the VAV air conditioner 3 is stopped, the VAV air conditioner return control is performed. The controller 5 determines whether or not the sensor detected temperature is equal to or higher than the set temperature + 2 ° C. in the representative indoor thermostat of the ambient external air conditioner 4 (S20). Although it is set to + 2 ° C., other set values may be used.

  When it determines with sensor detection temperature not being more than preset temperature +2 degreeC in S20, the controller 5 determines whether the stop of the VAV air conditioner 3 continued for 30 minutes or more (S21). If it is determined in S21 that the VAV air conditioner 3 has not been stopped for 30 minutes or longer, the controller 5 returns to S20 and determines again after a predetermined time. In the duration determination, the duration can be set to any time such as 1 hour (0 is acceptable).

  When it is determined in S20 that the sensor detection temperature is equal to or higher than the set temperature + 2 ° C. or when it is determined in S21 that the stop of the VAV air conditioner 3 has continued for 30 minutes or more, the controller 5 restarts the VAV air conditioner 3, Operation control for the VAV air conditioner 3 is started (S22). When the VAV air conditioner 3 is restarted, the VAV air conditioner stop control described above is also started, and the VAV air conditioner stop control is performed.

  The ambient air conditioner supply air temperature control will be described with reference to the flowchart of FIG. During operation of the ambient air conditioner 4, the supply air temperature control is performed. The controller 5 calculates a temperature difference between the set temperature of the VAV unit 3c and the sensor detection temperature for each VAV unit 3c of the VAV air conditioner 3 (S30). Then, the controller 5 averages the temperature differences for all the VAV units 3c, and calculates the average temperature difference ΔT (S31). A specific example of the calculation of the temperature difference for each VAV unit 3c in S30 and the calculation of the average temperature difference ΔT in S31 will be shown. As an example, the set temperature is subtracted from the sensor detection temperature for each VAV unit 3c (however, when the subtraction value is a negative value, it is 0), and the average value of the subtraction values (temperature differences) for all VAV units 3c. (Average temperature difference ΔT) is calculated. As another example, the set temperature is subtracted from the sensor detection temperature for each VAV unit 3c, and the average value (average temperature difference ΔT) of the subtraction values (temperature differences) for all the VAV units 3c is calculated (however, the average 0 if the value is negative).

  The controller 5 determines whether or not the average temperature difference ΔT is 4 ° C. or less (S32). When it is determined in S32 that the average temperature difference ΔT is 4 ° C. or less, the controller 5 sets [20 ° C. (initially set supply air temperature) −average temperature difference ΔT] as the supply air temperature of the ambient air conditioner 4 (S33). ). When it is determined in S32 that the average temperature difference ΔT exceeds 4 ° C., the controller 5 selects [20 ° C. (initially set supply air temperature) −4 ° C. (upper limit) = 16 ° C. (preset air supply temperature The lower limit value)] is set as the supply air temperature of the ambient air conditioner 4 (S34). Then, the controller 5 controls the opening and closing of the two-way valves of the coils 4e and 4f of the ambient air conditioner 4 and the frequency of the inverter of the fan 4h so as to reach the set supply air temperature (S35). Although the initial set supply air temperature is 20 ° C. and the upper limit value of the average temperature difference ΔT is 4 ° C., each temperature may be another set value in accordance with the supply air temperature lower limit value. Further, the lower limit value of the supply air temperature is 16 ° C., but other set values may be used.

  Thus, by setting the supply air temperature using the average value ΔT of the temperature difference between the set temperature of the VAV units 3c,... Distributed in the office room S1 and the sensor detection temperature, the office room S1 as a whole is set. The operation of the ambient air conditioner 4 can be controlled from the temperature load state (in particular, interior). As a result, from the low capacity (when the supply air temperature is 20 ° C) to the maximum capacity (when the supply air temperature is 16 ° C) as the air conditioning load processing capacity of the ambient air conditioner according to the temperature load state of the entire office room S1 The VAV air conditioner 3 can be stopped more effectively. As a result, the VAV air conditioner 3 is stopped when the ambient external air conditioner 4 is operating at less than the maximum capacity, and the air conditioning load processing of the VAV air conditioner 3 is performed when the ambient external air conditioner 4 is operating at the maximum capacity. The VAV air conditioner 3 operates only when necessary. As a result, since the air conveyance power of the ambient air conditioner 4 is small (the power consumption of the fan 4h is small), the power consumption can be suppressed as much as possible.

According to the air conditioning system 1, the VAV air conditioner is composed of an individual distributed package 2, a VAV air conditioner 3, and an ambient air conditioner 4 (particularly, the VAV air conditioner 3 and the ambient air conditioner 4) separated according to function. By optimally controlling 3 and the ambient air conditioner 4, efficient air conditioning load processing can be performed, and energy saving and CO ₂ saving can be achieved.

  In particular, the air conditioning system 1 stops the VAV air conditioner 3 having a larger air conveyance power than the ambient air conditioner 4 by idling stop control for the VAV air conditioner 3, and therefore, compared with a general single duct air conditioning system. It is excellent in energy saving by reducing air conveyance power (reducing power consumption by the fan 3g). When the VAV air conditioner 3 is stopped, the low load state of the air conditioner is determined under three stop conditions. Therefore, even if the VAV air conditioner 3 is stopped, the ambient air conditioner 4 having a small air conveyance power is sufficient. Air conditioning load can be handled.

  In addition, the air conditioning system 1 can operate the ambient air conditioner 4 at an optimum air supply temperature corresponding to the air conditioning load by controlling the air supply temperature for the ambient air conditioner 4. Can optimize the air conditioning load processing capacity. As a result, the VAV air conditioner 3 can be stopped more effectively. Moreover, the load factor of the coils 4e and 4f of the ambient air conditioner 4 is also improved, and the temperature difference of the cold / hot water heating medium is secured. That is, it takes a long time to use only the small coils 4e and 4f of the ambient air conditioner 4, and heat exchange can be efficiently performed with the small coils 4e and 4f.

  In addition, since the air conditioning system 1 uses air as a carrier heat medium, there is no risk of water loss and the like, and it has high reliability and high versatility for general office building air conditioning (particularly, tenant building air conditioning). In addition, since the air conditioning system 1 can control the air conditioning load processing capacity of each part of the office room S1 with the VAV units 3c,... Of the VAV air conditioner 3, the followability (= variability) at the time of partition installation is high. It is possible to deal with uneven distribution of personnel density. Even if a new tenant moves in and divides the booth, it can be handled.

Moreover, since the air conditioning system 1 is ensured by the ambient air conditioner 4 which always operates outside air volume adjustment and humidity adjustment, a high quality air conditioning environment can be maintained. That is, not only the room temperature but also the indoor CO ₂ concentration and humidity can be optimally controlled. For example, even when a minute cooling is performed by the VAV air conditioner 3 with respect to a task load having a high temperature by a device or the like in winter, the ambient humidity controller 4 can control the humidity to an optimum level. Moreover, even if the air volume in the individual distributed package 2 and the VAV air conditioner 3 is reduced at low load, the ambient air can be sufficiently introduced by the ambient air conditioner 4.

  As mentioned above, although embodiment which concerns on this invention was described, this invention is implemented in various forms, without being limited to the said embodiment.

  For example, in this embodiment, the present invention is applied to an air conditioning system including a VAV air conditioner for a task load, an ambient air conditioner for an ambient load, and an individual distributed package of perimeters, but at least for a VAV air conditioner and an ambient load for a task load. It can be applied to any air-conditioning system composed of ambient air conditioners.

  In the present embodiment, the air conditioning system performs both the idling stop control of the VAV air conditioner and the supply air temperature control of the ambient air conditioner. However, the air conditioning system may perform only one of the controls. Or it is good also as an air-conditioning system which does not perform both control. In the case of an air conditioning system that does not perform idling stop control of the VAV air conditioner, the ambient air conditioner may be prioritized and controlled over the VAV air conditioner.

  Further, in this embodiment, as the stop conditions 1 to 3 of the idling stop control, the two-way valve of the cold water / hot water coil of the VAV air conditioner is fully closed, the inverter frequency of the fan is the lower limit value, and the cooling request from the VAV unit The condition is that there is no signal, but other conditions may be used as the stop condition. Moreover, there is no continuation time determination with respect to the stop conditions 1 to 3, and the VAV air conditioner 3 may be stopped when all the stop conditions 1 to 3 are satisfied. Also, other conditions may be used for the return condition.

  In the present embodiment, as an air supply temperature control for the ambient air conditioner, an average value ΔT (upper limit of 4 ° C.) of the temperature difference between the set temperature of the VAV unit and the sensor detection temperature is set as the initial supply air temperature (20 ° C.) The temperature subtracted from the above is used as the supply air temperature, but other methods may be used for setting the supply temperature using the set temperature of the VAV unit and the sensor detection temperature.

  In this embodiment, the two-way valve is applied as the coil valve of the VAV air conditioner, but other valves such as a three-way valve may be applied.

  DESCRIPTION OF SYMBOLS 1 ... Air conditioning system, 2 ... Individual distributed package, 2a ... Suction inlet, 2b ... Outlet, 3 ... VAV air conditioner, 3a ... Air conditioner main body, 3b ... Duct, 3c ... VAV unit, 3d ... Filter, 3e ... Cold water Coil, 3f ... Warm water coil, 3g ... Fan, 3h ... Suction port, 3i ... Duct, 3j ... Two-way valve, 3k ... Temperature sensor, 3m ... Air outlet, 3n ... VAV controller, 4 ... Ambient air conditioner, 4a ... External air conditioner body, 4b ... duct, 4c ... outside air duct, 4d ... filter, 4e ... cold water coil, 4f ... hot water coil, 4g ... humidifier, 4h ... fan, 4i ... outlet, 5 ... controller, 6 ... exhaust duct .

Claims (5)

An air conditioning system that air-conditions indoor task loads and ambient loads using an all-air method,
An air conditioner that air-conditions a task load, has a plurality of VAV units corresponding to the task load in the room, and supplies air to the task load zone by adjusting the amount of air flow for each VAV unit. Machine,
An air conditioner that is an air conditioner for air-conditioning an ambient load and includes an ambient air conditioner that air-conditions outside air taken from outside and supplies air to an ambient load zone.   The air conditioning system according to claim 1, wherein the operation of the VAV air conditioner is stopped when a low load condition of the air conditioning load is satisfied.   The low load condition of the air conditioning load is that the coil valve of the VAV air conditioner is fully closed, the operating state of the fan is at a lower limit level, and there is no cooling request signal from the VAV unit. Air conditioning system.   The supply air temperature of the ambient air conditioner is controlled based on a set temperature and an indoor detection temperature for each VAV unit of the VAV air conditioner. Air conditioning system.   The temperature difference between the set temperature and the indoor detection temperature is calculated for each VAV unit of the VAV air conditioner, the average temperature difference of the temperature differences for all the calculated VAV units is calculated, and the calculated average temperature difference Is subtracted from the initial supply air temperature of the ambient air conditioner, and if the temperature obtained by the subtraction is equal to or higher than the lower limit value of the air supply temperature of the ambient air conditioner, the temperature obtained by the subtraction is The supply air temperature of the external air conditioner is used, and when the temperature obtained by the subtraction is less than the supply air temperature lower limit value, the supply air temperature lower limit value is set as the supply air temperature of the ambient air conditioner. The air conditioning system according to claim 4.

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