JP6594665B2 - Air conditioning system - Google Patents

Description

  The present invention relates to an air conditioning system that performs indoor air conditioning via a heat medium.

  For example, in the air conditioning system described in Patent Document 1, it is possible to suppress the operation and stop of the heat source machine from being repeated in a relatively short time by securing the minimum amount of circulating water necessary for operating the heat source machine. . In addition, if operation | movement and a stop of a heat source machine are repeated, durability of a heat source machine will fall.

Japanese Patent Laid-Open No. 2003-21377

  An object of the present invention is to suppress repeated operation and stop of a heat source machine by a method different from the method according to Patent Document 1.

  In this application, it is provided with the heat source machine (7A) which produces | generates the heat | fever provided to a heat medium, and the heat source machine control part which controls the action | operation of a heat source machine (7A), and a heat source machine control part is heat from a heat source machine (7A). Is based on the temperature difference between the heat medium before being applied (hereinafter referred to as a medium before application) and the heat medium after heat is applied from the heat source unit (7A) (hereinafter referred to as the medium after application). When the temperature difference stop process for judging whether or not to continue operating the heat source machine (7A) and the current heat quantity generated by the heat source machine (7A) is larger than the minimum heat quantity that can be generated by the heat source machine (7A) It is possible to execute an information generation process for generating information necessary for the temperature difference stop process to generate information for determining that the heat source unit (7A) will continue to be operated in the temperature difference stop process. It is.

Thereby, in this invention, it can suppress that an operation | movement and a stop of a heat source machine (7A) are repeated using a temperature difference stop process.
That is, in the temperature difference stop process, the heat source machine (7A) is based on the temperature difference between the temperature of the medium before application (hereinafter referred to as pre-application temperature) and the temperature of the medium after application (hereinafter referred to as post-application temperature). It is determined whether or not to continue operating.

  Therefore, if the information indicating the pre-applying temperature, the post-applying temperature, and the temperature difference is information for determining that the heat source unit (7A) is to continue operating, the heat source unit (7A) is repeatedly operated and stopped. Can be suppressed.

The present invention may be configured as follows.
That is, the heat source unit (7A) is configured to include at least the first heat source unit (7A1) and the second heat source unit (7A2). In the temperature difference stop process, the heat source unit is set when the temperature difference is equal to or greater than the threshold value. (7A) is determined to continue to operate, and the information generation process indicates a threshold value (hereinafter referred to as a first temperature difference) at the time of temperature difference stop processing executed for the first heat source machine (7A1). It is possible to generate information, and a threshold value at the time of temperature difference stop processing executed for the second heat source machine (7A2), which indicates a value different from the first temperature difference.

Thereby, since it can suppress that all of a several heat source machine (7A) stops, it can suppress that an operation | movement and a stop of a heat source machine (7A) are repeated.
By the way, immediately after the heat source machine (7A) is stopped and immediately after the heat source machine (7A) is operated (immediately after starting), the temperature of the post-application medium supplied from the heat source machine (7A) is continuously operating. There is a high possibility that the temperature of the medium after application supplied from (7A) is greatly different. For this reason, there is a possibility that the temperature of the heat medium supplied to the room greatly deviates from the set temperature.

  Therefore, in the invention according to claim 6, the information generation processing is performed when the other heat source machine that is operating when one of the first heat source machine (7A1) and the second heat source machine (7A2) is stopped. It is possible to generate information indicating a temperature lower or higher than that before stopping the temperature of the post-applying medium flowing out from the heat source, so that the heat source machine control unit becomes the temperature of the post-applying medium generated in the information generating process. The first operation control process for controlling the operation of the other heat source machine (7A) can be executed.

  In the invention according to claim 7, the information generation process flows out from the other heat source machine that is operating when one of the first heat source machine (7A1) and the second heat source machine (7A2) is activated. The information indicating the temperature of the post-applying medium that is lower or higher than that before the operation can be generated, and the heat source controller controls the other so that the temperature of the post-applying medium generated in the information generating process The second operation control process for controlling the operation of the heat source machine (7A) can be executed.

  Thereby, when providing cold heat with a heat source machine (7A), the temperature of the medium after provision can be made low compared with the temperature before a stop. Moreover, when giving warm heat with a heat source machine (7A), the temperature of the after-applying medium can be made higher than before stopping. Therefore, it is possible to suppress the temperature of the heat medium supplied to the room from greatly deviating from the set temperature.

  Incidentally, the reference numerals in parentheses for each of the above means are examples showing the correspondence with the specific means described in the embodiments described later, and the present invention is indicated by the reference numerals in the parentheses of the above respective means. It is not limited to specific means.

It is a figure which shows the outline | summary of an air conditioning system. It is a flowchart which shows control of an air conditioning system. It is a flowchart which shows control of an air conditioning system. It is a flowchart which shows control of an air conditioning system. It is a chart of a judgment item. It is a flowchart which shows the outline | summary of control of an air conditioning system. It is a figure which shows the outline | summary of an air conditioning system.

  The “embodiment of the invention” described below shows an example of the embodiment. In other words, the invention specific items described in the claims are not limited to the specific means and structures shown in the following embodiments.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. It should be noted that at least one member or part described with at least a reference numeral is provided, except for cases where “plural”, “two or more” and the like are omitted.

(First embodiment)
1. Outline of Air Conditioning System In the present embodiment, the air conditioning system according to the present invention is applied to an air conditioning system that performs air conditioning such as a communication equipment room or a server room. That is, the air conditioning system according to the present embodiment supplies a plurality of ICT devices by supplying cooling air to heat generating devices such as information communication technology devices (hereinafter referred to as ICT devices) installed in the server room. Cool down.

  The server room or the like needs to maintain the room in a preset air conditioning environment (hereinafter referred to as a setting environment). The setting environment refers to, for example, an indoor environment where the wet bulb temperature is 10 ° C. or higher and 30 ° C. or lower, and the relative humidity is 15% or higher and 50% or lower.

  As shown in FIG. 1, the air conditioning system 1 includes a heat source device 7 </ b> A and an indoor air conditioner 5. The heat source unit 7A generates heat (cold heat in the present embodiment) used for indoor air conditioning. The heat source unit 7A according to the present embodiment is composed of a plurality of vapor compression refrigerators. The heat source unit 7A is an air cooling type in which a radiator (not shown) such as a condenser is cooled by outside air.

  The air conditioning system 1 includes indoor air conditioning (hereinafter referred to as normal air conditioning operation) using heat generated by the heat source unit 7A, indoor air conditioning (hereinafter referred to as free cooling operation) using cold energy recovered from outdoor air, and the like. The operation mode can be executed.

  The heat source device 7A and the cooling tower 7B are also collectively referred to as a heat source device 7. The heat source device 7 and the indoor air conditioner 5 are collectively referred to as an air conditioner. And at the time of the free cooling operation of the air conditioner (air conditioning system 1) which concerns on this embodiment, cold heat is collect | recovered from outdoor air in the cooling tower 7B.

2. 2. Configuration of air conditioning system 2.1 Overview of configuration of air conditioning system The indoor air conditioner 5 generates cooling air supplied to the ICT equipment side. At least one (two in FIG. 1) indoor air conditioners 5 are installed in a server room or the like in which a plurality of ICT devices are installed. Each indoor air conditioner 5 is configured by an air handling unit (AHU) having an indoor heat exchanger 5A, a flow rate adjusting valve 5B, an indoor blower 5C, and the like.

  The indoor heat exchanger 5A exchanges heat between the cold water supplied from the heat source device 7 and the air supplied indoors. The heat source device 7 generates cold heat. The cold heat is supplied to the indoor heat exchanger 5A by cold water as a heat medium. The cold water is supplied to the indoor heat exchanger 5A (indoor air conditioner 5) by the primary pump P1 and the secondary pump P2.

  The flow rate adjusting valve 5B is provided in each indoor heat exchanger 5A. The flow rate adjusting valve 5B adjusts the amount of chilled water supplied to the indoor heat exchanger 5A. The indoor blower 5C is a blower capable of supplying cold air to the ICT equipment side and adjusting the air volume.

  The heat source device 7 is installed outdoors. The cold water generated in the heat source device 7 is supplied to the indoor (indoor air conditioner 5) side by the primary pump P1, and then distributed and supplied to each indoor air conditioner 5 by the secondary pump P2. The bypass flow path L1 is a chilled water circuit that absorbs a flow rate difference when the discharge flow rate of the primary pump P1 and the discharge flow rate of the secondary pump P2 are different.

  The heat source device 7 includes a heat source machine 7A, a cooling tower 7B, and the like. The heat source unit 7A circulates a refrigerant such as Freon to move the heat on the low temperature side to the high temperature side. In the air conditioner according to the present embodiment, the heat source unit 7A is configured by the plurality of heat source units 7A1 and 7A2.

  The cooling tower 7B cools the heat medium by causing the heat medium supplied to the low temperature side of the heat source unit 7A to exchange heat with at least one of air and water. In the present embodiment, the heat medium is cold water returning from the indoor air conditioner 5 (indoor heat exchanger 5A).

  That is, in the cooling tower 7B, cold water that has absorbed heat from room air and has risen in temperature is cooled in the atmosphere or the like. And in the free cooling operation which concerns on this embodiment, the cold water cooled with the cooling tower 7B is supplied to the indoor air conditioner 5 via the heat-source equipment 7A.

  The cooling tower 7B is provided with a cooling adjusting device (not shown) such as an outdoor blower or a sprinkler, an outdoor heat exchanger (not shown), and the like. The outdoor heat exchanger mainly exchanges heat between the atmosphere and cold water. The outdoor blower is a blower capable of blowing air to the outdoor heat exchanger and adjusting the amount of blown air. The water sprinkler is capable of watering the outdoor heat exchanger and adjusting the amount of water sprayed.

2.2 Capacity adjustment of air conditioner The heat exchange capacity generated in the indoor heat exchanger 5A, that is, the cooling capacity generated in the indoor heat exchanger 5A is determined by the opening degree of the flow control valve 5B, the air flow rate of the indoor fan 5C, and the indoor heat. The temperature varies depending on the amount of cold water supplied to the exchanger 5A (amount of water supplied by the secondary pump P2) and the temperature of the cold water (the refrigeration capacity generated by the heat source device 7).

  The refrigerating capacity generated in the heat source device 7, that is, the refrigerating capacity generated in the heat source unit 7A (vapor compression type refrigerator) is provided in the outdoor wet bulb temperature (heat radiation capacity in the vapor compression type refrigerator) and the vapor compression type refrigerator. It changes depending on the rotation speed of the compressor and the opening degree of the expansion valve.

  The operations of the heat source unit 7A and the indoor air conditioners 5 are controlled by the integrated control device 10. The integrated control device 10 indirectly controls each device such as the heat source unit 7A via the air conditioner control unit 10A, the secondary pump control unit 10B, the primary pump control unit 10C, the heat source control unit 10D, and the cooling tower control unit 10E. To do.

  The air conditioner control unit 10A controls the operation of the indoor air conditioner 5, that is, the flow rate adjustment valve 5B, the indoor blower 5C, and the like. The secondary pump control unit 10B controls the amount of cold water supplied to the indoor air conditioner 5 by controlling the operation of the secondary pump P2.

  The primary pump control unit 10C controls the operation of the primary pump P1. The heat source control unit 10D controls the heat source unit 7A, that is, the rotational speed of the compressor, the opening degree of the expansion valve, and the like. The cooling tower control unit 10E controls the amount of air blown from the outdoor fan.

  Note that the integrated control device 10 and the control units 10A to 10E each include a computer having a CPU, a ROM, a RAM, and the like. A program for executing the control is stored in advance in a nonvolatile storage unit such as a ROM provided in each of the integrated control device 10 and the control units 10A to 10E.

3. Control operation by integrated control device, etc. 3.1 Outline of control <Autonomous control of each control unit>
The integrated control device 10 issues a control command signal to each of the control units 10A to 10E. Each of the control units 10A to 10E includes a drive circuit that drives the control target, and directly controls the control target.

  The integrated control device 10 and each of the control units 10A to 10E are configured by a computer having a CPU, a ROM, a RAM, and the like, and a program incorporated in advance in the computer.

  And after receiving the control command signal from the integrated control apparatus 10, each control part 10A-10E autonomously performs the specific control for implement | achieving the content of the control command signal. That is, each control part 10A-10E cooperates with the integrated control apparatus 10, and controls each control object.

  For example, each indoor air conditioner 5 is provided with a blown air temperature sensor S1. The blown air temperature sensor S1 detects the temperature of air supplied indoors from the indoor air conditioner 5, that is, the temperature of the air for which heat exchange has been completed in the indoor heat exchanger 5A (hereinafter referred to as temperature after heat exchange).

  The air conditioner control unit 10 </ b> A is configured so that the temperature after heat exchange detected by the blown air temperature sensor S <b> 1 (hereinafter referred to as blown air temperature) The flow rate adjustment valve 5B and the indoor blower 5C are controlled so as to satisfy the target blowing temperature Tao.

  That is, the air conditioner control unit 10A autonomously controls the operation of the indoor air conditioner 5 so as to be the current target blow temperature Tao unless the new target blow temperature Tao is set by the integrated control device 10.

  The primary pump control unit 10C and the secondary pump control unit 10B autonomously control the primary pump P1 and the secondary pump P2 so that chilled water having a preset flow rate (hereinafter referred to as a target chilled water circulation amount Wro) circulates. To do.

  When the primary pump control unit 10C and the secondary pump control unit 10B receive the flow rate change command from the integrated control device 10, the received new circulation amount is set as the target cold water circulation amount Wro, and the primary pumps P1, 2 The next pump P2 is controlled autonomously.

  On the discharge side of the primary pump P1 or the secondary pump P2 (in this embodiment, the primary pump P1), a first cold water temperature sensor S2 that detects the temperature of the cold water is provided. The heat source controller 10 </ b> D is configured so that the chilled water temperature detected by the first chilled water temperature sensor S <b> 2 (hereinafter referred to as chilled water discharge temperature) is set as “target cold water discharge temperature (hereinafter referred to as target discharge). The heat source unit 7A is controlled so as to be “the cold water temperature Two”).

  That is, the heat source control unit 10D autonomously controls the operation of the heat source unit 7A so as to be the current target discharge cold water temperature Two, unless the new target discharge cold water temperature Two is set by the integrated control device 10.

  A second cold water temperature sensor S3 for detecting the temperature of the cold water is provided on the cold water outflow side of the cooling tower 7B, that is, the cold water inflow side of the heat source unit 7A. In the cooling tower control unit 10E, the temperature of the cooling water cooled by the cooling tower 7B becomes the “target cold water temperature (hereinafter referred to as target inflow cold water temperature Tco)” set by the integrated control device 10. Thus, the cooling tower 7B is controlled.

  That is, the cooling tower control unit 10E autonomously controls the operation of the cooling tower 7B so as to be the current target inflow cold water temperature Tco unless the new target inflow cold water temperature Tco is set by the integrated control device 10.

  The output signal of the outdoor temperature sensor S4 is input to the cooling tower control unit 10E and the heat source control unit 10D. The outdoor temperature sensor S4 detects the wet bulb temperature of the outdoor air. The cooling tower control unit 10E and the heat source control unit 10D are configured such that the wet bulb temperature of the outdoor air (hereinafter referred to as the outdoor temperature Tow) detected by the outdoor temperature sensor S4 is less than the threshold Th set by the integrated control device 10. Perform free cooling operation.

  That is, when the outside air temperature Tow <threshold Th, the cooling tower control unit 10E operates a cooling adjustment device such as an outdoor fan, and the heat source control unit 10D stops each heat source unit 7A. Thereby, the cold water cooled in the cooling tower 7B is supplied to the indoor air conditioner 5 without being recooled.

  In addition, control target values, such as the target blowing temperature Tao, the target chilled water circulation amount Wro, the target discharge chilled water temperature Tw, and the target inflow chilled water temperature Tc, are target ranges including a range set in advance with the control target value as a central value. .

  In addition to the detection signal of the first cold water temperature sensor S2, the detection signal of the second cold water temperature sensor S3 is also input to the heat source control unit 10D. The heat source control unit 10D can execute the temperature difference stop process and the information generation process in cooperation with the integrated control apparatus 10.

  The temperature difference stop process refers to a heat medium (hereinafter referred to as a medium before application) before the cooling heat is applied from the heat source apparatus 7A and a heat medium (hereinafter referred to as a medium after application) after the cooling heat is applied from the heat source apparatus 7A. .) Is a process for determining whether or not to continue operating the heat source unit 7A.

  The information generation process is an information generation process for generating information necessary for the temperature difference stop process when the current amount of cold heat generated by the heat source unit 7A is larger than the minimum load amount. This is a process for generating information for determining that the heat source apparatus 7A will continue to operate.

  The minimum load amount is a load amount corresponding to a cold heat amount that secures a safety factor of a predetermined level or more with reference to the minimum cold heat amount that can be generated by the heat source device 7A. Specifically, the minimum load amount is a value obtained by adding a predetermined heat amount α to the minimum cold heat amount.

  In addition, because of the characteristics of the heat source unit 7A, it is difficult to stably generate a cooling amount less than the minimum cooling amount by the heat source unit 7A. Therefore, the current amount of cooling generated by the heat source unit 7A is less than the minimum cooling amount. In this case, the heat source control unit 10D stops the heat source unit 7A.

  Specifically, the heat source controller 10D switches the heat source unit 7A when the temperature difference between the cold water discharge temperature (the temperature of the medium after application) and the inflow cold water temperature (the temperature of the medium before application) becomes less than the stop threshold Y. Stop. The integrated control device 10 generates information indicating the inflow chilled water temperature, that is, determines the target inflow chilled water temperature Tco.

  That is, the temperature difference stop process is always executed by the heat source controller 10D, and the information generation process is executed by the integrated controller 10 during the free cooling operation. In the present embodiment, the stop threshold Y is stored in the ROM of the heat source control unit 10D as a preset fixed value. The stop threshold Y is a kind of specification value determined for each heat source apparatus 7A.

  In the present embodiment, the current cold water discharge temperature (the medium after application) is set as information for determining that the heat source unit 7A is to be kept operating in the temperature difference stop process, that is, the target inflow cold water temperature Tco that does not stop the heat source unit 7A. A value obtained by adding a value X equal to or greater than the stop threshold Y to the (temperature) is employed. The value X is a fixed value set in advance.

  FIG. 2 is a flowchart showing an outline operation of the information generation process. That is, it is determined whether or not a value obtained by multiplying the value X by the current cold water flow rate (hereinafter referred to as “calculated heat amount”) is greater than the minimum load amount (S01).

  When it is determined that the calculated heat quantity is larger than the minimum load quantity (S01: YES), a value obtained by adding the value X to the current cold water discharge temperature T1 is determined as the target inflow cold water temperature Tco (S02).

  When it is determined that the calculated heat quantity is equal to or less than the minimum load quantity (S01: NO), a value X1 obtained by dividing the minimum load quantity by the current cold water flow rate is calculated (S03), and then the current cold water discharge temperature T1. A value obtained by adding the value X1 to the target inflow cold water temperature Tco is determined (S04).

  The minimum load amount is a value obtained by adding a predetermined heat amount α to the minimum cold heat amount. The value X is a value equal to or greater than the stop threshold Y. For this reason, when it is determined that the calculated heat amount is larger than the minimum load amount, this corresponds to a case where the current heat amount generated by the heat source unit 7A is larger than the minimum cold heat amount.

Since the value X1 is a value obtained by dividing the minimum load amount by the current cold water flow rate, a case where the value X1 is smaller than the stop threshold Y, that is, the case where the heat source unit 7A stops due to the temperature difference stop process may occur.
<Margin control mode>
In the margin control mode, each device constituting the air conditioner is controlled such that the margin A is maintained at a predetermined value (hereinafter referred to as a lower limit margin Ac) or more. The margin control mode is executed when the air conditioner is in operation.

  The margin A refers to a parameter relating to the difference between the maximum air conditioning capacity that can be exhibited by the air conditioner (air conditioning system 1) and the current air conditioning capacity. For example, the margin A for the indoor air conditioner 5 is defined by one of the following.

(1) 1- (Average opening degree of a plurality of flow control valves 5B)
(2) 1-{(average of actual number of revolutions of indoor fan 5C / maximum number of revolutions of indoor fan 5C)}
Maximum number of rotations: Maximum number of rotations of each indoor fan 5C (3) 1 / {(average of blown air temperature-target blown temperature Tao)}
(4) 1-{(average of blown air temperature-target blow temperature Tao)} / n
n: A value corresponding to (blow air temperature−target blow temperature Tao), which is a preset value, that is, n means an allowable temperature difference (allowable deviation temperature).

(5) 1 / {(average of cold water discharge temperature−target discharge cold water temperature Two)}
(6) 1-{(average of cold water discharge temperature−target discharge cold water temperature Two)} / n
n: A value corresponding to (cold water discharge temperature−target discharge cold water temperature Two), which is a preset value, that is, n means an allowable temperature difference (allowable deviation temperature).

  Then, the integrated control device 10 can maintain the set environment when the margin control mode is executed, and within a range in which the margin A can be maintained above a predetermined value, for example, the target discharge cold water temperature Two. The target chilled water circulation rate Wro is reduced while increasing the value.

  Thereby, the power consumption of the primary pump P1 or the secondary pump P2 can be reduced while the opening degree of the flow rate adjustment valve 5B is increased and the pressure loss in the flow rate adjustment valve 5B is reduced.

  When the margin A is less than the lower limit margin Ac, the integrated control device 10 does not execute the margin control mode and the free cooling operation, but performs the normal air conditioning operation using the autonomous control of each of the control units 10A to 10E. To do.

  The reason is that when the margin A is less than the lower limit margin Ac, there is a high possibility that the air conditioning environment in the server room deviates from the set environment. In other words, if the margin A is small, there is a high possibility that the cooling heat supplied from the air conditioner will be transiently insufficient when the amount of heat generated by the ICT equipment increases rapidly, and it is difficult to ensure reliability.

3.2 Switching control between normal air conditioning operation and free cooling operation <Overview of switching control>
As described above, the free cooling operation is executed when the outside air temperature Tow is less than the threshold Th, and the normal air conditioning operation is executed when the outside air temperature Tow is equal to or higher than the threshold Th.

  In other words, when the integrated control device 10 sets a value equal to or higher than the outside air temperature Tow as the threshold Th, the free cooling operation is executed. On the other hand, when the integrated control device 10 sets a value lower than the outside air temperature Tow as the threshold value Th, the free cooling operation is not executed and the normal air conditioning operation is executed.

  Then, the integrated control device 10 executes at least “a determination process for determining whether or not to execute the free cooling operation” and “an estimation process for estimating whether or not the air conditioning environment in the server room deviates from the set environment”. Then, it is determined whether or not the free cooling operation is continuously performed, and the threshold value Th is determined.

  In the determination process, it is determined whether or not to perform the free cooling operation using an environmental index that directly or indirectly indicates the indoor air conditioning environment and the outdoor environment. The determination process includes a first determination process and a second determination process.

  In the first determination process, the cold heat collected in the cooling tower 7B is stored in the server room using the temperature of the cold water from which the heat generated in the server room has been collected (hereinafter referred to as the return water temperature TW2) and the outside air temperature Tow. It is determined whether or not supply is possible.

  The return water temperature TW2 is a value using the detection value of the return water temperature sensor S5. And the integrated control apparatus 10 (1st judgment process) acquires the temperature (henceforth supply temperature TW1) of the cold water which can be supplied from the cooling tower 7B using the return water temperature TW2 and the external temperature Tow.

  The integrated control device 10 acquires the supply temperature TW1 by the following method. That is, when the preset time has not elapsed since the start of the free cooling operation, the supply temperature TW1 is estimated (calculated) based on the return water temperature TW2, the outside air temperature Tow, the flow rate, and the like.

  When a preset time has elapsed since the start of the free cooling operation, the temperature detected by the second cold water temperature sensor S3 is acquired as the supply temperature TW1. In addition, the estimation method of supply temperature TW1 is not ask | required. In this embodiment, the supply temperature TW1 is estimated using an LCEM simulation tool distributed from the Ministry of Land, Infrastructure, Transport and Tourism.

  In the first determination process, when the difference between the return water temperature TW2 and the supply temperature TW1 is larger than the preset temperature difference X, it is determined that the cold supply to the server room is impossible and the return is performed. When the difference between the water temperature TW2 and the supply temperature TW1 is less than the temperature difference X, it is determined that cold heat can be supplied into the server room.

  In the second determination process, when it is determined that supply is possible in the first determination process, it is determined that the free cooling operation is performed, and when it is determined that supply is not possible, the free cooling operation is determined not to be performed. .

  That is, in the determination processing according to the present embodiment, whether or not to perform the free cooling operation using the supply temperature TW1, the return water temperature TW2, etc. as an environmental index that directly or indirectly indicates the air conditioning environment and the outdoor environment in the server room. To be judged.

In the estimation processing, “estimation as to whether or not the air-conditioning environment in the server room deviates from the set environment” is performed using the state index and the environment index indicating the operating state of the air-conditioning apparatus.
In the status index, for example, (a) “margin A”, (b) “information indicating whether or not the number of devices in a failure state among a plurality of devices constituting the air conditioner is equal to or less than a preset number. ", (C)" information indicating whether or not the air conditioner corresponds to a preset emergency state ", and (d)" a sensor that detects the operating state of the air conditioner corresponds to a preset failure state " Information indicating whether or not to perform "or the like.

  In addition to the supply temperature TW1 and the return water temperature TW2, the environmental index includes, for example, “information indicating whether the rate of increase in the amount of heat generated in the server room exceeds a preset rate of increase” or the like. It is.

  Then, when it is estimated that “the air conditioning environment in the server room deviates from the setting environment”, the integrated control device 10 executes the normal operation process for executing the normal air conditioning operation, and the “air conditioning environment in the server room” If it is not estimated that “departs from the setting environment”, a value capable of continuously executing the free cooling operation is set as the threshold Th.

  Specifically, when it is estimated that “the air conditioning environment in the server room deviates from the setting environment”, the integrated control device 10 sets the initial setting value (default value) as the threshold Th. The initial set value is a value that is determined in advance based on tests, operation results, and the like, and is a value that is stored in advance in a nonvolatile storage unit (not shown) such as a ROM.

  If it is not estimated that “the air conditioning environment in the server room deviates from the setting environment”, that is, if it can be estimated that “the server room can be maintained in the setting environment”, the integrated control device 10 The value is set as the threshold Th. In the present embodiment, the integrated control device 10 sets the outside air temperature Tow + Y (a preset value) as the threshold Th.

<Details of switching control>
3 and 4 are flowcharts showing the switching control executed by the integrated control apparatus 10. A program (software) for executing the switching control is stored in advance in a nonvolatile storage unit such as a ROM.

In addition to the signals from the sensors S1 to S5, the following signals are input to the integrated control device 10.
(A) Output signal of an indoor temperature sensor (not shown) that detects the wet bulb temperature of the indoor air (b) Output signal of an indoor humidity sensor (not shown) that detects the relative humidity of the indoor air (c) Output signal indicating failure of indoor air conditioner 5 (AHU) (c) Signal indicating that power supply to air conditioning system 1 (air conditioner) has stopped (d) Signal indicating power consumption of ICT equipment (e) Signal indicating that cold water has leaked at any point (f) Signal indicating that communication with important points such as sensors and equipment with high control priority has been interrupted (g) Each flow control valve Signal indicating 5B opening degree The switching control shown in FIGS. 3 and 4 is executed at predetermined time intervals after being activated together with the activation of the air conditioner (air conditioning system). And it stops when the air conditioner (air conditioning system) stops.

  When the switching control is activated, first, the decision item NO. 1 to judgment item NO. It is determined whether any of the items 8 is detected (S1). In addition, judgment item NO. 1 to judgment item NO. 8 is a specific example of a state index and an environmental index.

  If it is determined in S1 that one of the determination items has been detected (S1: YES), as shown in FIG. 3, the threshold Th for determining the free cooling operation is reset to the initial set value, and After the control target value of the cooling adjustment device such as the outdoor blower is reset to the initial setting value (S3), the present control is temporarily ended.

  If it is determined in S1 that none of the determination items are detected (S1: NO), an elapsed time from when any determination item is not detected is set in advance. It is determined whether or not the predetermined time has been exceeded (S5). If it is determined that the time has not elapsed (S5: NO), this control is temporarily terminated.

  If it is determined that the time has elapsed (S5: YES), the determination item NO. It is determined whether 9 (see FIG. 5) has been detected (S7). Judgment item NO. 9 is detected (S7: YES), the threshold Th for determining the free cooling operation is reset to the initial set value, and the control target value of the cooling adjusting device such as the outdoor blower is the initial set value. (S9), this control is temporarily terminated.

  Judgment item NO. 9 is determined not to be detected (S7: NO), the determination item NO. It is determined whether or not the elapsed time from when 9 is not detected exceeds a preset time (S9).

  If it is determined that the time has not elapsed (S9: NO), this control is temporarily terminated. When it is determined that the time has elapsed (S9: YES), it is determined whether or not the heat source device 7A is operating (thermo-on) (S13).

  When it is determined that the heat source unit 7A is operating (thermo-on) (S13: YES), the threshold Th for free cooling operation determination is reset to the initial set value, and the cooling adjustment device such as an outdoor blower is After the control target value is reset to the initial set value (S15), this control is temporarily terminated.

  When it is determined that the heat source device 7A is not operating (thermo-on) (S13: NO), it is determined whether a preset time has elapsed since the start of the free cooling operation (S17). When it is determined that the time has elapsed (S17: YES), the temperature detected by the second cold water temperature sensor S3 is set to the supply temperature TW1 (S19).

  When it is determined that the time has not elapsed (S17: NO), a value estimated (calculated) based on the return water temperature TW2, the outside air temperature Tow, the flow rate, and the like is set as the supply temperature TW1 (S18). ). Next, it is determined whether or not the difference between the return water temperature TW2 and the supply temperature TW1 is greater than a preset temperature difference X (S21).

  When it is determined that the difference between the return water temperature TW2 and the supply temperature TW1 is greater than the preset temperature difference X (S21: YES), the threshold Th for free cooling operation determination is reset to the initial set value, And after the control target value of cooling adjustment apparatuses, such as an outdoor air blower, is reset to the initial setting value (S23), this control is once complete | finished.

  When it is determined that the difference between the return water temperature TW2 and the supply temperature TW1 is less than the temperature difference X (S21: NO), a value equal to or higher than the outside air temperature Tow (= the outside air temperature Tow + Y) is set as the threshold Th ( S25), and the temperature detected by the second cold water temperature sensor S3, that is, the target inflow cold water temperature Tc is set to the target discharge cold water temperature Tw (S27).

4). Features of the air conditioning system according to the present embodiment In the present embodiment, information (Tco = T1 + X) for determining that the heat source unit 7A is continuously operated in the temperature difference stop process is generated. Utilization of the heat source unit 7A can be prevented from being repeated.

  By the way, immediately after the stop of the heat source unit 7A and immediately after the operation of the heat source unit 7A (immediately after startup), the temperature of the cold water supplied from the heat source unit 7A is the cold water supplied from the heat source unit 7A when continuously operating. There is a high possibility that the temperature will greatly differ. For this reason, if the operation and stop of the heat source unit 7A are repeated, the temperature of the cold water supplied to the indoor air conditioner 5 may greatly deviate from the set temperature.

  On the other hand, in this embodiment, since it can suppress that operation | movement and a stop of 7 A of heat source apparatuses are repeated, it can suppress that the temperature of the cold water supplied to the indoor air conditioner 5 deviates largely from setting temperature.

(Second Embodiment)
In the above-described embodiment, the threshold value (hereinafter referred to as the first temperature difference Y1) at the time of the temperature difference stop process executed for the first heat source device 7A1 and the temperature difference executed for the second heat source device 7A2. The threshold value during the stop process (hereinafter referred to as the second temperature difference Y2) was the same value at the same position.

  On the other hand, in the information generation process according to the present embodiment, it is possible to generate information in which the first temperature difference Y1 and the second temperature difference Y2 are different values. Thereby, in this embodiment, since it can suppress that 1st heat-source equipment 7A1 and 2nd heat-source equipment 7A2 stop simultaneously, it can suppress that operation | movement and a stop of heat-source equipment 7A are repeated.

(Third embodiment)
In the information generation processing according to the present embodiment, when one of the first heat source machine 7A1 and the second heat source machine 7A2 is activated, the temperature of the cold water flowing out from the other heat source machine that is in operation is set before operation. Information indicating a lower temperature can be generated.

  That is, in the information generation process according to the present embodiment, when the first heat source machine 7A1 is restarted when the first heat source machine 7A1 is stopped first and the second heat source machine 7A2 is operating. The information which makes the target discharge cold water temperature Two2 about the cold water which flows out out of 2nd heat-source equipment 7A2 lower than target discharge cold-water temperature Two2 before 1st heat-source equipment 7A1 stops is produced | generated.

Thereby, in this embodiment, the following effects can be acquired.
That is, the temperature of the cold water supplied from the heat source device 7A immediately after the operation (immediately after the start) is higher than the temperature of the cold water supplied from the heat source device 7A that is continuously operated. For this reason, the temperature of the cold water supplied to the indoor air conditioner 5 may greatly deviate from the set temperature.

  On the other hand, in this embodiment, for example, when the first heat source machine 7A1 is restarted, the target discharge cold water temperature Two2 for the cold water flowing out from the second heat source machine 7A2 is the same as before the first heat source machine 7A1 is stopped. The temperature is lower than the target discharge cold water temperature Two2.

  Therefore, even if the temperature of the cold water supplied from the first heat source device 7A immediately after the operation (immediately after the start) is high, the temperature of the cold water supplied from the second heat source device 7A2 is low. It is possible to suppress the temperature of the supplied cold water from greatly deviating from the set temperature.

  FIG. 6 is a flowchart illustrating an operation example in the case where the first heat source unit 7A1 is restarted when the first heat source unit 7A1 is stopped first and the second heat source unit 7A2 is operating. .

  When this control is activated, it is first determined whether or not the first heat source device 7A1 has been activated (S31). When it is determined that the first heat source machine 7A1 has been activated (S31: YES), the target discharged cold water temperature Two2 for the cold water flowing out from the second heat source machine 7A2 is the target discharged cold water before the first heat source machine 7A1 is stopped. The temperature is determined to be lower by k ° C. than the temperature Two2 (S33).

  When it is determined that the first heat source device 7A1 is not activated (S31: NO), the target discharge cold water temperature Two2 is the target discharge cold water temperature Two of the heat source device 7A, that is, the target of cold water supplied to the indoor air conditioner 5. It is determined whether or not it matches the target discharge cold water temperature Two as the temperature (S35).

  Note that the target discharge cold water temperature Two2 and the target discharge cold water temperature Two need not exactly match. If the target discharge cold water temperature Two2 is within a predetermined temperature range centered on the target discharge cold water temperature Two, it is determined that the target discharge cold water temperature Two2 and the target discharge cold water temperature Two match.

  When it is determined that the target discharge cold water temperature Two2 and the target discharge cold water temperature Two are not coincident (S35: NO), the cold water temperature (cold water discharge temperature) detected by the first cold water temperature sensor S2 is the target. It is determined whether or not the temperature is equal to or higher than the discharge cold water temperature Two (S37).

  When it is determined that the cold water discharge temperature is equal to or higher than the target discharge cold water temperature Two (S37: YES), the target discharge cold water temperature Two2 is lowered by a predetermined temperature (for example, 0.1 ° C.) (S39).

  When it is determined that the cold water discharge temperature is lower than the target discharge cold water temperature Two (S37: NO), the target discharge cold water temperature Two2 is increased by a predetermined temperature (for example, 0.1 ° C.) (S41).

(Fourth embodiment)
In the information generation process according to the present embodiment, when one of the first heat source machine 7A1 and the second heat source machine 7A2 is stopped, the temperature of the cold water flowing out from the other heat source machine that is operating is stopped before the stop. Information indicating a lower temperature can be generated.

  That is, in the information generation processing according to the present embodiment, when the first heat source machine 7A1 is stopped from the state in which the first heat source machine 7A1 and the second heat source machine 7A2 are operating, the information flows out from the second heat source machine 7A2. Information that the target discharged cold water temperature Two2 for cold water is lower than the target discharged cold water temperature Two2 before the first heat source machine 7A1 stops is generated.

Thereby, in this embodiment, the following effects can be acquired.
That is, when one of the first heat source machine 7A1 and the second heat source machine 7A2 stops, the temperature of the cold water supplied from the heat source machine 7A is such that the first heat source machine 7A1 and the second heat source machine 7A2 are continuously operated. Higher than if For this reason, the temperature of the cold water supplied to the indoor air conditioner 5 may greatly deviate from the set temperature.

  In contrast, in the present embodiment, for example, when the first heat source machine 7A1 is stopped, the target discharge cold water temperature Two2 for the cold water flowing out from the second heat source machine 7A2 is the target before the first heat source machine 7A1 is stopped. The temperature is lower than the discharge cold water temperature Two2.

  Therefore, even when the first heat source unit 7A is stopped, the temperature of the cold water supplied from the second heat source unit 7A2 is low, so that the temperature of the cold water supplied to the indoor air conditioner 5 greatly deviates from the set temperature. This can be suppressed.

(Fifth embodiment)
In the first embodiment, the heat medium cooled in the cooling tower 7B is directly supplied to the indoor air conditioner 5 via the heat source unit 7A.

  In contrast, in the present embodiment, for example, as shown in FIG. 7, during the free cooling operation, the heat medium cooled in the cooling tower 7B bypasses the heat source unit 7A and is directly supplied to the indoor air conditioner 5. Is done.

  During normal air-conditioning operation, the heat medium cooled in the cooling tower 7B circulates between the cooling tower 7B and the heat source unit 7A, and the heat medium (hereinafter also referred to as cooling water) is the heat source unit 7A. The high pressure side (eg, condenser) is cooled.

  For this reason, in the air conditioning system 1 according to the present embodiment, the cooling water cooled by the cooling tower 7B bypasses the heat source unit 7A and is led to the indoor air conditioner 5, and the cooling water flowing out from the indoor air conditioner 5 is removed. A path that bypasses the heat source unit 7A and leads to the cooling tower 7B is provided.

  The cooling water pump P3 is a pump that circulates cooling water between the cooling tower 7B and the heat source unit 7A during normal air conditioning operation. The cooling water pump control unit 10F controls the operation of the cooling water pump P3 to control the circulation amount of the cooling water.

  The second cold water pump P4 is a pump that circulates the heat medium between the cooling tower 7B and the indoor air conditioner 5 during the free cooling operation. The second cold water pump control unit 10G controls the operation of the second cold water pump P4 to control the circulation amount of the cold water.

(Other embodiments)
In the above-described embodiment, the present invention has been described by taking the case of using cold heat as an example. However, the present invention is not limited to this, and can also be applied to the case of using warm heat. In addition, when applying 3rd Embodiment and 4th Embodiment to the air-conditioning system using warm heat, the temperature of the heat medium which flows out from the other heat-source machine which is operate | moving is made into high temperature compared with before operation. There is a need.

  In the above-described embodiment, the heat source unit 7A is configured by the vapor compression refrigerator, but the present invention is not limited to this. For example, another type of refrigerator may be used as the heat source unit 7A that generates cold. A combustor may also be used as the heat source unit 7A that generates warm heat.

  In the embodiment described above, the integrated control device 10 and the heat source control unit 10D configure the heat source machine control unit described in the claims, and the integrated control device 10 and the cooling tower control unit 10E describe in the claims. However, the present invention is not limited to this. For example, the integrated control device 10 may be integrated by incorporating the heat source control unit 10D and the cooling tower control unit 10E.

  Further, the present invention is not limited to the above-described embodiment as long as it matches the gist of the invention described in the claims. That is, you may combine at least 2 embodiment of the above-mentioned embodiment.

DESCRIPTION OF SYMBOLS 1 ... Air conditioning system 5 ... Indoor air conditioner 5B ... Flow control valve 5A ... Each indoor heat exchanger 5C ... Indoor fan 7A ... Heat source machine 7B ... Cooling tower 10 ... Integrated control apparatus 10A ... Air conditioner control part 10B ... Secondary pump control Part 10C ... Primary pump control part 10D ... Heat source control part 10E ... Cooling tower control part 10F ... Cooling water pump control part

Claims (5)

In an air conditioning system that air-conditions the room by supplying a heat medium to the indoor unit,
A heat source device that generates heat to be applied to the heat medium;
A heat source unit controller for controlling the operation of the heat source unit;
A cooling tower for cooling the heat medium before the heat from the heat source unit is applied (hereinafter, referred to pre-grant medium.) With the pre-grant medium and the outside air by heat exchange,
A cooling tower controller for controlling the operation of the cooling tower,
The heat source machine controller is
Heat medium after heat is applied from the front SL with given before media body the heat source equipment on the basis of the temperature difference (hereinafter, referred to. Post-grant medium), determines whether to continue running the heat source apparatus Temperature difference stop processing, and information generation processing for generating information necessary for the temperature difference stop processing (hereinafter referred to as necessary information) can be executed,
The necessary information is information necessary for the temperature difference stop process when the current heat amount generated by the heat source unit is larger than the minimum heat amount that can be generated by the heat source unit, and Information to determine that the heat source machine will continue to operate,
In the temperature difference stop process, when the temperature difference is equal to or greater than a threshold, it is determined that the heat source machine is to be continuously operated,
In the information generation process, information indicating at least the temperature of the medium before application is generated,
The air conditioner characterized in that the cooling tower control unit is capable of executing a temperature management process for setting the temperature of the heat medium flowing out of the cooling tower to the temperature of the pre-application medium generated in the information generation process. system. Free cooling operation for supplying the pre-application medium cooled in the cooling tower to the indoor unit is possible,
The air conditioning system according to claim 1, wherein the information generation process is executed during the free cooling operation. The heat source machine is configured to include at least a first heat source machine and a second heat source machine,
In the temperature difference stop process, when the temperature difference is equal to or greater than a threshold, it is determined that the heat source machine is to be continuously operated,
In the information generation process,
Information indicating the threshold value (hereinafter referred to as a first temperature difference) during the temperature difference stop process executed for the first heat source machine, and the temperature difference stop executed for the second heat source machine The air conditioning system according to claim 1, wherein the threshold value at the time of processing and information indicating a value different from the first temperature difference can be generated. In the information generation process, when one of the first heat source machine and the second heat source machine stops, the temperature of the post-application medium flowing out from the other heat source machine that is operating is compared with that before the stop. Information indicating low or high temperature can be generated,
The heat source machine control unit is capable of executing a first operation control process for controlling an operation of the other heat source machine so as to be a temperature of the post-application medium generated in the information generation process. The air conditioning system according to claim 3. In the information generation process, when one of the first heat source device and the second heat source device is started from a stopped state, the temperature of the post-applying medium that flows out from the other heat source device that is operating is operated. Can generate information indicating lower or higher temperature than before,
The heat source machine control unit is capable of executing a second operation control process for controlling the operation of the other heat source machine so as to be the temperature of the post-application medium generated in the information generation process. The air conditioning system according to claim 3 or 4.