JP2018200149A - Air conditioning system using snow ice - Google Patents

Abstract

To provide an air conditioning system using snow ice, etc. that can achieve high energy-saving effects while maintaining effects of an indirect outdoor air cooling machine.SOLUTION: In an indirect outdoor air cooling machine, brine is circulated in an inside air heat exchanger 11 and an outside air heat exchanger 13 through brine piping 16. Heat exchange between brine and return air (RA) is carried out in the inside air heat exchanger 11 while heat exchange between brine and outside air is carried out in the outside air heat exchanger 13. In a snow ice cold water cooling machine, cold water cooled by the cold of snow ice (snow mountain) 21 is flowing in a cold water pipe 24. Brine is cooled by cold water by a liquid-liquid heat exchanger 31.SELECTED DRAWING: Figure 1

Description

  The present invention relates to an air conditioning system using snow and ice.

  In recent years, an air conditioning system has been considered in which a snowy mountain is created from snowfall in winter in a snowy region and the like, and the cold heat of this snowy mountain is used outside of winter.

  For example, the prior art described in Patent Document 1 includes a snow storage unit in which snow is accumulated outside the room. Then, switching between the outside air OA and the snow-cooled outside air SOA is led to the outside air passage, and the cooling heat of the snow-cold water is led to the cooling coil.

JP 2012-145289 A

  Here, because there are devices such as servers that generate a large amount of heat in the air-conditioning target room that is the target of air-conditioning, the allowable range between indoor temperature and humidity is narrow, and management of temperature and humidity is difficult . However, the air conditioning system of Patent Document 1 performs outside air cooling in which outside air is directly introduced into the air conditioning target room. Therefore, it is necessary to provide humidification means when the outside air introduced into the air-conditioning target room is excessively dry, or to provide dust prevention means when there is a lot of dust in the outside air.

  In addition, since the air conditioning system of Patent Document 1 directly introduces outside air into the air-conditioning target room, it is determined whether to cool directly using outside air or to cool using snow and ice according to the outside air temperature. There is also a need to switch.

  An object of the present invention is to make it possible to cool an air-conditioning target space in an energy efficient manner by using both a snow and ice cold water cooler and an indirect outside air cooler.

The snow and ice utilization air conditioning system of the present invention has the following configuration.
A first heat exchanger that exchanges heat between the outside air and the refrigerant, a second heat exchanger that exchanges heat between the return air that is return air from the air-conditioning target space and the refrigerant, and a refrigerant pump An indirect outdoor air cooler that circulates the refrigerant to the first heat exchanger and the second heat exchanger via the first pipe by the refrigerant pump in operation;
A snow and ice cold water cooler that has a snow and ice pump and circulates cold water in the second pipe by the snow and ice pump in operation and cools it by the cold heat of the snow mountain;
A third heat exchanger for causing heat exchange between the refrigerant and the cold water after the heat exchange is performed in the first heat exchanger.

  ADVANTAGE OF THE INVENTION According to this invention, a snow-ice cold water cooler and an indirect external air cooler can be used together, and the air-conditioning object space can be efficiently cooled.

It is a block diagram of the snow-ice utilization air conditioning system of this example. It is a process flowchart figure of the control apparatus in the structure shown in FIG. It is an example of control operation | movement of each structure shown in FIG. It is a process flowchart figure of the control apparatus in another structural example. It is an example of control operation of each composition in other composition examples.

  Embodiments of the present invention will be described below with reference to the drawings.

[Embodiment 1]
FIG. 1 is a configuration diagram of the snow-ice-use air conditioning system of this example.

  The snow / ice utilization air conditioning system in the illustrated example is an air conditioner that uses the indirect outdoor air cooler 10 and the snow / ice cold water cooler 20 in combination. The indirect outside air cooler 10 itself may have an existing configuration. Similarly, the snow / ice cold water cooler 20 itself may have an existing configuration.

  The snow-ice-use air conditioning system in the illustrated example does not include a cooling unit (a cooling unit composed of a compressor, an evaporator, etc .; referred to as a general refrigerator) using a vapor compression refrigeration cycle. Also good. That is, the snow / ice-use air conditioning system of this example may be in the form of the “indirect outside air cooler 10 + snow / ice cold water cooler 20” shown in the figure or the “indirect outside air cooler 10 + snow / ice cold water cooler 20 + general refrigeration” not shown. It may be in the form of a “machine”.

  Here, the form of “indirect outside air cooler 10 + snow ice cold water cooler 20” shown in the figure is referred to as [Embodiment 1], and the form of “indirect outside air cooler 10 + snow ice cold water cooler 20 + general refrigerator” (not shown) is used. This will be described as [Embodiment 2]. First, [Embodiment 1] will be described.

  In the case of the configuration of “indirect outside air cooler 10 + snow ice cold water cooler 20” as in the example shown in FIG. 1, the indirect outside air cooler 10 alone can maintain the cooling capacity necessary for cooling the cooling target space such as a data center. In such a case (for example, when an air supply SA described later can be maintained at a set temperature), the snow / ice cold water cooler 20 is not operated. Then, if the indirect outside air cooler 10 alone cannot maintain the cooling capacity necessary for cooling the cooling target space, the snow / ice cold water cooler 20 is controlled to operate for the insufficient cooling capacity. Such control can be realized, for example, by adjusting and controlling the flow rate of cold water flowing in the liquid-liquid heat exchanger 31 described later. If such control can be appropriately executed, it is possible to provide an air-conditioning system with high energy-saving effect that can effectively use the cold energy of snow and ice. This effect is the same even in the case of the configuration of “indirect outside air cooler 10 + snow ice cold water cooler 20 + general refrigerator” (not shown).

  According to the configuration of the “indirect outside air cooler 10 + snow and ice cold water cooler 20”, a general refrigerator is not used, so the energy saving effect is high, and the outside air temperature is increased by using the cold heat of snow and ice. Even if only 10 does not function effectively, it can function effectively as a whole. “Effectively functioning” here means that, for example, the cooling capacity necessary for cooling the cooling target space can be maintained, and as an example, the supply air temperature is maintained at the set temperature.

  Further, even in the case of the configuration of “indirect outside air cooler 10 + snow and ice cold water cooler 20 + general refrigerator”, it is not necessary to operate the general refrigerator until the outside air temperature becomes higher than a certain level by using the cold heat of snow and ice. High energy-saving effect can be obtained.

  In addition, each of the above effects can be realized while maintaining the effect of the indirect outside air cooler. As described above, the effect of the indirect outside air cooler is that, as compared with the direct outside air cooling, there is no need for a dust-proof measure against humidifying means or dust in the outside air.

  In FIG. 1, the configuration related to the indirect outside air cooler 10 is an inside air heat exchanger 11, an inside air fan 12, an outside air heat exchanger 13, an outside air fan 14, a brine pump 15, and a brine pipe 16. An indoor air heat exchanger 11 and an indoor air fan 12 are provided in an indoor unit 1 provided in the building. An outdoor air heat exchanger 13 and an outdoor air fan 14 are provided in the outdoor unit 2 provided outside the building.

  Further, the configuration related to the snow / ice cold water cooler 20 is a snow / ice (snow mountain) 21, a melted water tank 22, a snow / ice pump 23, and a cold water pipe 24.

  The illustrated liquid-liquid heat exchanger 31 is provided as a configuration for performing heat exchange between the indirect outside air cooler 10 and the snow / ice cold water cooler 20. In the liquid-liquid heat exchanger 31, heat exchange between the refrigerants (here, brine and cold water) is performed, and heat exchange with the air is not performed, so that the size can be reduced.

  In the indirect outside air cooler 10, while the brine pump 15 is in operation, brine (refrigerant) circulates through the inside air heat exchanger 11 and the outside air heat exchanger 13 via the brine pipe 16. Then, the return air (RA) is taken into the indoor unit 1 by the inside air fan 12 and passed through the inside air heat exchanger 11 to exchange heat with brine. As a result, basically, the return air (RA) is cooled and cooled to be supplied to the cooling target space as supply air (SA). However, naturally, when the temperature of the brine is higher than the temperature of the return air (RA), the return air (RA) cannot be cooled.

  The cooling target space is, for example, a server room, and the supply air (SA) rises in temperature by cooling the server device or the like and becomes the return air (RA). Further, the temperature of the brine rises due to heat exchange with the return air (RA) in the inside air heat exchanger 11 and is returned to the outside air heat exchanger 13, where heat exchange with the outside air (OA) is performed in the outside air heat exchanger 13. Done.

  During operation, the outside air fan 14 takes outside air (OA) into the outdoor unit 2, passes the outside air heat exchanger 13 to exchange heat with brine, and then exhausts the air outside the outdoor unit 2 as exhaust (EA). Discharge.

  The indirect outside air cooler 10 is configured to perform heat exchange between return air (RA) and outside air (OA) indirectly through a brine. Therefore, since the outside air (OA) does not flow into the space to be cooled, there is no concern that dust or the like will flow into the space to be cooled, and it is not necessary to provide a humidifying means.

  In the snow / ice cold water cooler 20, cold water circulates in the cold water pipe 24 while the snow / ice pump 23 is in operation. The cold water pipe 24 is provided so as to pass through the melted water tank 22. The melted water from the snow ice (snow mountain) 21 (melted snow) passes / stores in the melted water tank 22. Thus, the cold water circulating in the cold water pipe 24 is cooled by heat exchange with the snowmelt water in the melted water tank 22. That is, the cold water is cooled by the cold heat of the snow ice (snow mountain) 21. However, the present invention is not limited to this example. For example, the snow melting water itself may flow in the cold water pipe 24 as the cold water.

  Here, unlike the general refrigerator, the indirect outside air cooler 10 does not have a compressor and can perform energy saving operation as compared with a general refrigerator. However, when the temperature of the outside air (OA) is higher than the temperature of the brine. Is virtually nonfunctional. Further, even when the temperature of the outside air (OA) is lower than the temperature of the brine, if the outside air (OA) becomes high to some extent, the brine cannot be sufficiently cooled, and hence the cooling capacity necessary for cooling the cooling target space. Cannot be maintained. In such a case, in the liquid-liquid heat exchanger 31, the cooling capacity necessary for cooling the cooling target space is maintained by further cooling the brine by the cooling heat of the snow / ice cold water cooler 20. The outside air temperature in this description basically means the outside air (OA) temperature.

  As shown in the figure, the liquid-liquid heat exchanger 31 is connected with the cold water pipe 24 and the brine pipe 16. When the brine pump 15 and the snow ice pump 23 are in operation, the liquid-liquid heat exchanger 31 performs the above operation. Heat exchange between the brine and the cold water is performed. Basically, the brine is cooled by cold water.

  The snow and ice utilizing air conditioning system of this example is further provided with a control device 40 for controlling the entire snow and ice utilizing air conditioning system. Further, a temperature sensor 3 for measuring the temperature of the supply air (SA) is provided.

  The control device 40 is connected to the temperature sensor 3, the inside air fan 12, the outside air fan 14, the brine pump 15, the snow ice pump 23, and the like via a communication line (not shown). And these each structure is controlled via this communication line. That is, the control device 40 executes, for example, activation / stop of the inside air fan 12 and the outside air fan 14 and control of the fan rotation speed via a communication line (not shown). Or control device 40 performs starting / stop of brine pump 15 and snow ice pump 23, and control of the number of rotations of a pump via a communication line not illustrated, for example.

  The control device 40 stores the set temperature for the supply air (SA) in its built-in memory. The control device 40 acquires the measured value of the temperature of the supply air (SA) by the temperature sensor 3 through the communication line (not shown) as needed, and based on the measured value, the set temperature, etc. The control of (12, 14, 15, 23) is performed. This is basically controlled so that the temperature of the supply air (SA) is maintained at the set temperature.

  The control device 40 includes a storage device such as a CPU and a memory (not shown), a communication interface, and the like, for example, and a predetermined application program is stored in the storage device in advance. By executing this application program, the CPU performs the above-described various controls, or performs the processes shown in FIGS. 2 and 4 described later, and maintains the temperature of the supply air (SA) at the temperature set value.

  Hereinafter, with reference to FIG. 2 and FIG. 3, the operation example of the snow-ice utilization air conditioning system of the structural example shown in FIG. 1 is demonstrated. Although not described one by one in the following description, each process of FIG. 2 is executed by the control device 40, and the operation of each component shown in FIG. 3 is realized by this process. FIG. 3 shows an operation example of each component. This operation is realized by the control device 40 controlling each component in accordance with the processing of FIG.

  FIG. 2 is a diagram illustrating an example of the processing operation of the control device 40. However, FIG. 2 shows a case where the outside air temperature rises from a very low state.

  In FIG. 3, the horizontal axis represents the outside air temperature when the return air (RA) temperature is constant, for example. The outside temperature is very low at the left end in the figure, and the outside temperature increases as it goes to the right.

  As shown in FIG. 3, when the outside air temperature is low, only the indirect outside air cooler 10 can cope. However, when the outside air temperature becomes high, it is necessary to operate with the “indirect outside air cooler 10 + the snow / ice cold water cooler 20”. Further, in the case of FIG. 5 described later, when the outside air temperature becomes higher, the general refrigerator is also operated.

  And the control apparatus 40 controls a snow-ice utilization air-conditioning system in various modes shown in figure, and controls based on the temperature etc. of an air supply (SA), but this respond | corresponded to the present external temperature as a result. Operation control is performed in the mode. In the example shown in FIG. 3, the various modes are assumed to have mode “A0-1”, mode “A0-2”, mode A1, mode A2, and mode B1 in order from the lowest outside air temperature. That is, the vehicle is operated in a mode corresponding to the outside air temperature. For example, when the outside air temperature is very low, the vehicle is operated in the mode “A0-1”.

  However, in actuality, since not only the outside air temperature but also the return air (RA) temperature (corresponding to the load) is affected, the operation is performed in a mode corresponding to the outside air temperature and the return air (RA) temperature. However, here, as described above, it is assumed that the mode control according to the outside air temperature is performed by assuming that the temperature of the return air (RA) is constant.

  In FIG. 2, first, steps S11 to S14 show processing operations of the control device 40 in the mode “A0-1” in FIG. As shown in FIG. 3, in the mode “A0-1”, the outside air fan 14 is in a stopped state, and the brine pump 15 is intermittently operated (operating repeatedly ON / OFF). During the intermittent operation, the rotation speed of the brine pump 15 is minimized. Such an operation is realized by the control processing of steps S11 to S14 by the control device 40. In FIG. 2, in the initial state, the outside air fan 14, the brine pump 15, and the snow and ice pump 23 are all stopped. The inside air fan 12 is controlled separately, and is not particularly described here.

  In the processing of steps S11 to S14, the brine pump 15 is intermittently operated in steps S11, S13, and S14, and at any time, in step S12, it is checked whether or not the brine pump 15 is insufficiently cooled in the intermittent operation. When the temperature of the supply air (SA) cannot be maintained at the set temperature, it is determined that the cooling is insufficient. That is, in step S12, for example, it is determined whether or not “measured temperature of supply air (SA)> SA set temperature”. If the determination is YES, the process proceeds to step S15. This means transition to the mode “A0-2” in FIG.

  In the process of steps S11 to S14, the brine pump 15 is activated to operate at the minimum rotation speed (step S11). When a predetermined time (for example, 1 minute) has elapsed, the determination of step S12 is performed, If “SA measurement temperature ≦ SA set temperature” (step S12, NO), the brine pump 15 is stopped (step S13). When the timer is set and started and the timer is up (for example, after 1 minute has elapsed) (step S14), the brine pump 15 is started again to operate at the minimum rotation speed (step S11).

  When “measured temperature of supply air (SA)> SA set temperature” (step S12, YES), the process proceeds to a mode in which the processes of steps S15 to S18 are performed. This shows the processing operation of the control device 40 in the mode “A0-2” in FIG. As shown in FIG. 3, in the mode “A0-2”, the brine pump 15 is operating at the minimum rotation speed while maintaining the above step S11, and the outside air fan 14 is intermittently operated. Note that the rotational speed of the outside air fan 14 is set to the lowest during the intermittent operation.

  In the processing of steps S15 to S18, the outside air fan 14 is activated to operate at the minimum rotational speed (step S15), and when a predetermined time (for example, 1 minute) has elapsed, the determination of step S16 is performed. Note that the determination itself in step S16 is the same as that in step S12, and it is determined whether or not “measurement temperature of supply air (SA) ≦ SA set temperature” (whether cooling is insufficient). The difference is that it is determined whether or not the cooling is insufficient in the state of “intermittent operation of the brine pump 15” in the step S12, whereas in the step S16, “intermittent operation of the outside air fan 14 + the minimum rotation speed of the brine pump 15”. In this state, it is determined whether or not cooling is insufficient in the “operation” state.

  When “measurement temperature of supply air (SA) ≦ SA set temperature” (step S16, NO), the outside air fan 14 is stopped (step S17). When the timer is set and started and the timer is up (for example, when 1 minute has elapsed) (step S18), the outside air fan 14 is started again to operate at the minimum rotational speed (step S15).

  When the mode “A0-2” is compared with the mode “A0-1”, the mode “A0-2” has higher power consumption and higher cooling capacity.

  If step S16 is YES, that is, if it is determined that the cooling is insufficient in "intermittent operation of the outside air fan + minimum operation of the brine pump 15", the process proceeds to step S19. This means transition to mode A1 in FIG.

  As shown in FIG. 3, in the mode A1, the outside air fan 14 is operated at a constant minimum rotational speed, and the brine pump 15 is PID controlled (step S19). This PID control (Proportional-Integral-Differential Controller) is a general control and controls the temperature of the supply air SA (supply air temperature) to be a set temperature. For example, if “measurement temperature of supply air (SA)> SA set temperature”, the rotation speed of the brine pump 15 is increased by a certain number, but if “measurement temperature of supply air (SA) <SA set temperature”, the brine pump The rotational speed of the brine pump 15 is maintained at the current state if the rotational speed of 15 is lowered by a certain number and “measured temperature of the supply air (SA) = SA set temperature”.

  Then, even if the rotation speed of the brine pump 15 is maximized (100%), if “measured temperature of supply air (SA)> SA set temperature” (step S20, YES), the process proceeds to step S21. This transitions to mode A2 in FIG.

  As shown in FIG. 3, in mode A2, the brine pump 15 is operated at a constant maximum rotational speed, and the outside air fan 14 is PID-controlled (step S21). Also in this case, as in step S19, PID control is performed so that the supply air temperature becomes the set temperature. For example, if “measurement temperature of supply air (SA)> SA set temperature”, the rotational speed of the outside air fan 14 is increased by a certain number, but if “measurement temperature of supply air (SA) <SA set temperature”, the outside air fan. The rotational speed of the outside air fan 14 is maintained at the current state if the rotational speed of the air supply 14 is lowered by a certain number and “measured temperature of the supply air (SA) = SA set temperature”.

  Then, even if the rotational speed of the outside air fan 14 is maximized (100%), if “measured temperature of supply air (SA)> SA set temperature” (step S22, YES), the process proceeds to step S23. In FIG. 3, this transitions to mode B1.

  As shown in FIG. 3, in mode B1, the snow and ice pump 23 is operated, and the snow and ice cold water cooler 20 is put into an operating state. In each of the mode “A0-1”, the mode “A0-2”, the mode A1, and the mode A2, the snow / ice cold water cooler 20 is in a stopped state, and the indirect outside air cooler 10 is in a state of operating independently.

  On the other hand, in mode B1, the indirect outside air cooler 10 and the snow / ice cold water cooler 20 are operated in combination.

  From this, when the said step S22 is YES, the snow ice pump 23 is started first (step S23). Then, the snow ice pump 23 is PID controlled (step S24). Also in this case, as in step S19, PID control is performed so that the supply air temperature becomes the set temperature.

  However, in the example of FIG. 3, the rotational speed of the outside air fan 14 is controlled in conjunction with the PID control of the snow ice pump 23. For example, the user arbitrarily creates a correspondence table (not shown) in which the rotational speed of the snow ice pump 23 and the rotational speed of the outside air fan 14 are associated in advance and stores them in the memory or the like. Thus, every time the rotation speed of the snow ice pump 23 is newly determined by the PID control of the snow ice pump 23, the rotation speed of the outside air fan 14 corresponding to this rotation speed is obtained from the association table.

  For example, when the rotation speed of the snow ice pump 23 is 20%, the rotation speed of the outside air fan 14 is 80%, and when the rotation speed of the snow ice pump 23 is 70%, The rotational speed is set to be 30%, such that the rotational speed of the outside air fan 14 decreases as the rotational speed of the snow ice pump 23 increases. However, the present invention is not limited to this example. For example, 20% means a rotational speed corresponding to 20% of the maximum rotational speed.

  In the illustrated example, while executing the process of step S24, a determination is made of "is the snow and ice pump 23 operating at maximum (at 100%)" in step S25. If the determination is NO, the process returns to step S24. Even if the determination is YES, the loop processing returns to step S24 as in the case of NO. If the determination in step S25 is YES, it is merely a confirmation / display, for example, indicating / notifying that the vehicle is operating with the maximum air conditioning output.

  The reason why the rotational speed of the outside air fan 14 decreases as the rotational speed of the snow and ice pump 23 increases in conjunction with the PID control of the snow and ice pump 23 as described above can be handled by the independent operation of the indirect outdoor air cooler 10. This is because, in a situation where the outside air temperature rises so much that the outside air temperature rises, the cooling effect of the brine by the outside air is small, and in some cases, there is a possibility that the effect may be adverse. The adverse effect is, for example, a case where the temperature of the brine rises due to heat exchange with the outside air OA, but is not limited to this case.

  As shown in FIG. 3, the control in the mode B1 essentially controls the amount of cold water flowing through the liquid-liquid heat exchanger 31, and as an example therefor, the snow ice pump as described above. Although the rotational speed of 23 is controlled, it is not restricted to this example. For example, a three-way valve (not shown) and a bypass pipe are further provided, and the opening degree of the three-way valve is controlled so that a part of the cold water supplied from the snow ice pump 23 bypasses the liquid-liquid heat exchanger 31. The amount of cold water flowing through the liquid-liquid heat exchanger 31 may be adjusted and controlled.

  In the mode B1, the outdoor air fan 14 is finally stopped (the rotational speed is “0”) as shown in the figure due to the increase in the outside air temperature. This state is “substantially the indirect outside air cooler 10 is Therefore, it may be regarded as a state substantially equivalent to the single operation state of the snow / ice cold water cooler 20. That is, since the brine pump 15 is operating in this state, the brine circulates, but since the outside air fan 14 is stopped, there is almost no heat exchange with the outside air (OA), and the liquid-liquid heat exchanger. It may be considered that only heat exchange with cold water by 31 is performed. That is, it can be considered that the snow / ice cold water cooler 20 alone is in a state where the return air (RA) is cooled by the cold heat of the cold water indirectly through the brine.

  Further, as described above, FIG. 2 is shown on the assumption that the temperature continues to rise from a low temperature state, and is not shown in the case of a temperature drop.

  First, during operation in the mode B1, when the outside air temperature decreases, control is performed to decrease the rotational speed of the snow ice pump 23 accordingly. If the outside air temperature continues to fall, the snow ice pump 23 will eventually be stopped (rotation speed = 0), so that the mode A2 will be entered. In mode B1, although not shown in FIG. 2, while performing the PID control of the snow and ice pump 23 in step S24, not only step S25 but also, for example, “whether the snow and ice pump 23 is in a stopped state (rotation speed = 0)? A process (not shown) for determining “no” is also performed. If the snow and ice pump 23 is in a stopped state, the process proceeds to step S21, and thus the process proceeds to mode A2.

  During operation in mode A2, when the outside air temperature falls, control is performed to reduce the rotational speed of the outside air fan 14 accordingly. If the outside air temperature continues to fall, the outside air fan 14 is operated at the minimum number of revolutions at any time, so that the mode A1 is entered. In the mode A2, although not shown in FIG. 2, while performing the PID control of the outside air fan 14 in step S21, it is determined not only at step S22 but also “whether or not the outside air fan 14 has the minimum number of revolutions” as needed. Processing (not shown) is also performed. If the outside air fan 14 is operating at the minimum rotation speed, the process proceeds to step S19, and thus the process proceeds to mode A1.

  During operation in mode A1, when the outside air temperature decreases, control is performed to reduce the rotational speed of the brine pump 15 accordingly. Then, as the outside air temperature continues to fall, the brine pump 15 is operated at the minimum number of revolutions at any time. At that time, the mode shifts to the mode “A0-2”. In mode A1, although not shown in FIG. 2, while executing the PID control of the brine pump 15 in step S19, not only step S20 but also, for example, “whether the brine pump 15 is at the minimum number of revolutions” is determined at any time. (Not shown) is also performed. If the brine pump 15 is operating at the minimum number of revolutions, the process proceeds to step S15, and thus the process proceeds to mode "A0-2".

  During operation in the mode “A0-2”, the brine pump 15 is operated at the minimum number of rotations and the outside air fan 14 is intermittently operated as described above, not the control according to the outside air temperature. In the mode “A0-2”, the determination in step S16 (determination of whether cooling is insufficient) is performed as needed. In addition to this, “determination of whether cooling is excessive” (not shown) may also be performed. Good. When it is determined that the cooling is excessive, the mode is shifted to “A0-1”.

  In addition, the determination method of whether it is overcooling determines that it is overcooling, for example, when the measured temperature of supply air (SA) is lower than the SA set temperature to some extent. That is, it is determined whether or not “measurement temperature of supply air (SA) + α ≦ SA set temperature” (α; positive value set arbitrarily in advance). If the determination is YES, it is determined that the cooling is excessive. To do.

  In addition, although not particularly illustrated, as described above, the configuration of the snow / ice utilization air conditioning system of this example is not limited to the configuration of FIG. 1, but the configuration of “indirect outside air cooler 10 + snow / ice cold water cooler 20 + general refrigerator”. It does not matter.

  Although not shown, the general air conditioner may have a general configuration, that is, for example, an evaporator, a compressor, a condenser, an expansion valve, and a pipe for circulating a refrigerant in these configurations. ing. The refrigerant circulates in the order of evaporator → compressor → condenser → expansion valve → evaporator.

  The evaporator is installed, for example, in the indoor unit 1 and on the downstream side of the indoor air heat exchanger 11. The downstream / upstream is based on the air flow. Therefore, in this configuration, the return air (RA) first passes through the internal air heat exchanger 11 and then passes through the evaporator. Basically, the return air (RA) first decreases in temperature by heat exchange with the brine when passing through the internal air heat exchanger 11, and then heat exchange with the refrigerant when passing through the evaporator. As a result, the temperature further decreases.

  Further, the condenser is installed, for example, in the outdoor unit 2 and provided downstream of the outdoor air heat exchanger 13. Thus, the outside air (OA) first passes through the outside air heat exchanger 13 and then passes through the condenser. The outside air (OA) first exchanges heat with the brine when passing through the outside air heat exchanger 13, and then exchanges heat with the refrigerant that has been compressed by the compressor into a high temperature / high pressure state in the condenser. become. In addition, this structure can be said that the outside air fan 14 was made into the structure common to the indirect outside air cooler 10 and the general refrigerator.

  However, the present invention is not limited to this example. For example, the condenser may be provided separately from the outside air heat exchanger 13 and the outside air fan 14, and a condenser fan may be further provided so that the outside air (OA) passes through the condenser by the condenser fan. Good. In the case of this configuration, for example, the indirect outside air cooler 10 is substantially stopped by stopping the outside air fan 14, but the general refrigerator can function by operating the condenser fan (of course, of course). It is assumed that the compressor is in operation).

  The indirect outside air cooler according to the present invention includes, for example, a first heat exchanger that performs heat exchange between outside air and refrigerant (brine), and heat exchange between return air that is return air from the air-conditioning target space and refrigerant. It may also be said that the second heat exchanger that performs the operation and the refrigerant pump are used, and the refrigerant is circulated to the first heat exchanger and the second heat exchanger through the first pipe by the refrigerant pump in operation. it can. For example, the outside air heat exchanger 13 is an example of a first heat exchanger, the inside air heat exchanger 11 is an example of a second heat exchanger, the brine pump 15 is an example of a refrigerant pump, and the brine pipe You may consider that 16 is an example of 1st piping.

  The snow / ice cold water cooler according to the present invention has a snow / ice pump (an example is the above-mentioned snow / ice pump 23), and circulates cold water in the second pipe by the snow / ice pump in operation to produce a snow mountain (an example is snow / ice (snow mountain). It can also be said that it is cooled by the cold heat of 21). The cold water pipe 24 is an example of a second pipe.

  The snow / ice utilization air conditioning system according to the present invention, for example, performs heat exchange between the indirect outside air cooler, the snow / ice cold water cooler, and the refrigerant and cold water after heat exchange is performed in the first heat exchanger. It can also be considered that it has the 3rd heat exchanger (an example is the liquid-liquid heat exchanger 31) for making it perform.

  Further, the snow / ice utilization air conditioning system according to the present invention further includes, for example, a control device (for example, the control device 40), and the control device, for example, operates the indirect outside air cooler with the snow / ice pump stopped. When the predetermined condition cannot be satisfied, the snow and ice pump is operated to cool the refrigerant with cold water by the third heat exchanger.

  In addition, the snow and ice-use air conditioning system according to the present invention is configured to supply, for example, the return air after heat exchange with the refrigerant by the second heat exchanger to the air conditioning target space as supply air (cold air). You may further have the temperature measurement means (an example is the temperature sensor 3) which measures temperature. In this case, when the predetermined condition cannot be satisfied, for example, even if the indirect outside air cooler is operated at the maximum cooling capacity (by control of the control device), the measured value of the supply air temperature is the set temperature. It is a case where it is not possible to maintain.

  The control device uses, for example, the first mode in which the indirect outside air cooler is operated alone, and the second mode in which the indirect outside air cooler and the snow / ice cold water cooler are operated in combination. Control snow and ice cold water coolers. The first mode includes, for example, the mode “A0-1”, mode “A0-2”, mode A1, and mode A2. However, the present invention is not limited to this example. For example, the first mode may include only mode A1 and mode A2 (that is, in this example, even if the outside air temperature decreases during operation in mode A1, mode “A0-1” or mode A (The operation does not shift to “A0-2” and operation is continued in mode A1).

  In addition, for example, when the supply air temperature cannot be maintained at the set temperature even when the indirect outside air cooler is operated at the maximum cooling capacity during operation in the first mode, the control device performs control to switch to the second mode. .

  Further, the snow / ice-use air conditioning system according to the present invention may have a configuration further including a general air conditioner that is a refrigerating air conditioner having a compressor, as described in [Embodiment 2] described later. In this case, for example, if the supply air temperature cannot be maintained at the set value even if the snow / ice cold water cooler is operated at the maximum cooling capacity during operation in the second mode, the control device also operates the general cooler. Control to switch to the third mode, which is the mode to be performed. The third mode is, for example, a mode C1 described later, but is not limited to this example.

[Embodiment 2]
Hereinafter, with reference to FIG. 4 and FIG. 5, an operation example of the snow / ice use air conditioning system of the configuration example of “indirect outside air cooler 10 + snow / ice cold water cooler 20 + general refrigerator” (not shown) will be described.

  The snow / ice-use air conditioning system of “indirect outside air cooler 10 + snow / ice cold water cooler 20 + general refrigerator” includes a control device (not shown).

  The control device (not shown) also has a CPU, a memory, and the like, similar to the control device 40, and the CPU executes an application program stored in advance in the memory, whereby the processing shown in FIGS. 4 and 5 is performed. Operation is realized.

  FIG. 4 is a flowchart illustrating the processing operation of the control device (not shown). However, FIG. 4 shows the case where the outside air temperature rises from a very low state as in FIG.

  In FIG. 4, the same processes as those in FIG. 2 are denoted by the same reference numerals, and the description thereof is omitted or simplified. Also in FIG. 5, the operations of the mode “A0-1”, the mode “A0-2”, the mode A1, the mode A2, and the mode B1 shown in FIG. 5 are the same as those in FIG.

  Hereinafter, with reference to FIG. 4 and FIG. 5, an operation example of the snow / ice utilization air conditioning system of the “indirect outside air cooler 10 + snow / ice cold water cooler 20 + general refrigerator” will be described. Although not described one by one in the following description, each process in FIG. 4 is executed by the control device (not shown), and the operation of each component shown in FIG. 5 is realized by this process. FIG. 5 shows an operation example of each component. This operation is realized by the control device (not shown) controlling each component in accordance with the processing of FIG.

  From the above, the description of FIGS. 4 and 5 will be started from the operation state of mode B1.

  As described in FIGS. 2 and 3, in mode B1, the flow rate of cold water flowing through the liquid-liquid heat exchanger 31 by starting the snow ice pump 23 (step S23) and performing PID control (step S24). Thus, the temperature of the supply air (SA) is controlled to be maintained at the set temperature. As described above, the output control of the outside air fan 14 is also performed in conjunction with the output control of the snow and ice pump 23. As described above, this is controlled such that when the rotational speed of the snow ice pump 23 is increased, the rotational speed of the outside air fan 14 is decreased.

  Then, when the output of the snow ice pump 23 (the flow rate of the cold water flowing through the liquid-liquid heat exchanger 31) becomes the maximum (if the temperature of the supply air (SA) cannot be maintained at the set temperature even if the maximum) (step) (S25, YES), the process proceeds to step S26. In FIG. 5, this shifts to mode C1, that is, shifts to a mode in which a general refrigerator is also operated.

  In mode C1, the snow and ice pump 23 is continuously operated and the brine pump 15 is also continuously operated. In the configuration of FIG. 1, even if the snow ice pump 23 is operating, if the brine pump 15 is stopped, the brine cannot be cooled by the cold heat of the snow ice, and the snow ice cold water cooler 20 does not function substantially. It becomes a state. The mode C1 is a mode in which the operation is performed by “snow / ice cold water cooler 20 + general cooler”, and the snow / ice cold water cooler 20 is also functioned. In the illustrated example, both the snow ice pump 23 and the brine pump 15 are operated at the maximum capacity.

  In mode C1, the brine pump 15 cannot be stopped in order to make the snow / ice cold water cooler 20 function as described above, and the outside air fan 14 must be operated for the general refrigerator (its condenser). The indirect outside air cooler 10 can be said to be in a substantially operating state. However, the control intention is to stop the operation of the indirect outside air cooler 10 in the mode C1, and therefore, the mode C1 is assumed to be a mode operated by the “snow-ice cold water cooler 20 + general cooler”.

  In mode C1, the rotational speed of the outside air fan 14 is controlled so that the air volume by the outside air fan 14 becomes “the minimum air volume necessary for compressor operation”. “The minimum air volume of the outside air fan 14 required for compressor operation” is an air volume that does not raise the outlet temperature of the refrigerant from the condenser above a certain temperature. The reason for doing this is to suppress such adverse effects when the indirect outdoor air cooler 10 is operated when the outside air temperature is high to some extent. Such a control method for setting the air volume by the outside air fan 14 to “the minimum air volume necessary for compressor operation” is an existing control method, and is not specifically described here. Here, the temperature of the supply air SA is maintained at a set value by controlling the rotation speed of the compressor.

  However, the present invention is not limited to this example. For example, if the above-described condenser fan is separately provided, in mode C1, the outside air fan 14 may be stopped and the condenser fan may be started and operated. By doing so, the above-described adverse effects can be suppressed. In this case, even in the mode C2, the outside air fan 14 remains stopped and the condenser fan is continuously operated.

    In step S26 of FIG. 4, the compressor which is the structure of a general refrigerator is started, and the said compressor is PID-controlled. As described above, this controls the rotational speed of the compressor so as to maintain the temperature of the supply air SA at the set temperature. Further, the rotational speed of the outside air fan 14 is controlled as described above. Then, for example, the measured value of the temperature of the outside air (OA) and the measured value of the temperature of the return air (RA) are acquired at any time, and it is checked whether or not “outside air temperature <return air temperature” (step S27). ). Although not shown in FIG. 1, in this example, a temperature sensor that measures the temperature of the outside air (OA) and a temperature sensor that measures the temperature of the return air (RA) are provided.

  If “outside air temperature ≧ return air temperature” (step S27, NO), the brine pump 15 and the snow and ice pump 23 are stopped (step S28), and the process returns to step S26. In other words, the snow / ice cold water cooler 20 is stopped and the general refrigerator is operated independently. This corresponds to transition to mode C2 shown in FIG.

  In the example shown in FIG. 5, in mode C2, the compressor continues to perform PID control, and the outside air fan 14 operates at the maximum output. In mode C2, the indirect outside air cooler 10 is also substantially stopped, so there is no need to consider the above adverse effects, and the outside air fan 14 can be operated at the maximum output.

  Also, in the figure, when the general refrigerator (compressor) is in a state of operating at the maximum capacity (step S29, YES), the loop exits to “maximum air conditioning output”, but this is simply “maximum air conditioning output”, for example. It is only necessary to display that the vehicle is in operation, and the process may return to step S26 without exiting the loop.

  Although not shown, during the operation in the mode C2, a “processing for determining whether“ the outside air temperature <the return air temperature ”is not performed” (not shown) is performed, and in the case of the determination YES (that is, “the outside air temperature”). <When it becomes <return air temperature>) It may be made to change to mode C1. In this case, the brine pump 15 and the snow and ice pump 23 are started and always operated at the maximum rotation speed. During operation in mode C1, a process for determining whether or not the compressor is in the operating state with the lowest output is performed. If the determination is YES, the compressor is stopped and the process proceeds to step S24. It may be made to change to mode B1 by changing.

  As described above, according to the snow / ice utilization air conditioning system of the present example, etc., it is an air conditioning system using snow / ice, and a high energy saving effect can be obtained while maintaining the effect of the indirect outside air cooler.

  According to the snow-ice-use air conditioning system of this example, etc., it is an air-conditioning system that uses snow-ice and maintains the effect of the indirect outside air cooler by operating the indirect outside air cooler and the snow ice cold water cooler efficiently. However, a higher energy saving effect can be obtained.

  Further, the configuration of Patent Document 1 is a system that introduces outside air directly into the air-conditioning target room, and it is necessary to determine whether to cool directly using outside air or to use snow and ice depending on the outside air temperature. is there. On the other hand, according to the snow and ice air-conditioning system of this example, since the outside air is not introduced into the air-conditioned room, it is not affected by the humidity or dust of the outside air and is basically switched according to the outside temperature. No control is necessary. In the snow / ice-use air conditioning system of this example, it is possible to determine whether the indirect outdoor air cooler is operated alone or the snow / ice cold water cooler is also used by measuring the temperature of the supply air (SA).

DESCRIPTION OF SYMBOLS 1 Indoor unit 2 Outdoor unit 3 Temperature sensor 10 Indirect outside air cooler 11 Inside air heat exchanger 12 Inside air fan 13 Outside air heat exchanger 14 Outside air fan 15 Brine pump 16 Brine piping 20 Snow ice cold water air conditioner 21 Snow ice (snow mountain)
22 Melting tank 23 Snow and ice pump 24 Cold water pipe 31 Liquid-liquid heat exchanger 40 Control device

The snow and ice-use air conditioning system of the present invention is
A fan that takes in outside air, a first heat exchanger that exchanges heat between the outside air taken in by the fan and the refrigerant, and a second that exchanges heat between the return air that is return air from the air-conditioning target space and the refrigerant An indirect outdoor air cooler that has a heat exchanger and a refrigerant pump, and circulates the refrigerant to the first heat exchanger and the second heat exchanger via the first pipe by the refrigerant pump in operation ;
A snow / ice cold water cooler that has a snow / ice pump and circulates cold water in the second pipe by the snow / ice pump in operation and cools it by the cold heat of the snow mountain;
A third heat exchanger for performing heat exchange between the refrigerant and the cold water after the heat exchange is performed in the first heat exchanger ;
At least the first mode in which the indirect outside air cooler is operated alone and the second mode in which the indirect outside air cooler and the snow / ice cold water cooler are operated in combination are used, and the indirect outside air cooler and the snow / ice are used. A control device for controlling the chilled water cooler,
The control device associates the flow rate of the cold water circulating in the second pipe of the snow and ice cold water cooler with the rotational speed of the fan of the indirect outside air cooler while operating in the second mode. It is characterized by controlling .

Claims (6)

A first heat exchanger that exchanges heat between the outside air and the refrigerant, a second heat exchanger that exchanges heat between the return air that is return air from the air-conditioning target space and the refrigerant, and a refrigerant pump, An indirect outdoor air cooler that circulates the refrigerant to the first heat exchanger and the second heat exchanger via the first pipe by the refrigerant pump in operation;
A snow / ice cold water cooler that has a snow / ice pump and circulates cold water in the second pipe by the snow / ice pump in operation and cools it by the cold heat of the snow mountain;
A third heat exchanger for performing heat exchange between the refrigerant and the cold water after the heat exchange is performed in the first heat exchanger;
A snow and ice-use air conditioning system characterized by comprising: The snow and ice-use air conditioning system further includes a control device,
The control device operates the snow and ice pump when the predetermined condition is not satisfied during operation of the indirect outside air cooler while the snow and ice pump is stopped. The snow-ice-use air conditioning system according to claim 1, wherein the air conditioner is cooled by cold water. Supplying the return air after heat exchange with the refrigerant by the second heat exchanger to the air conditioning target space as supply air;
A temperature measuring means for measuring the temperature of the supply air;
The case where the predetermined condition cannot be satisfied is a case where the measured value of the temperature of the supply air cannot maintain the set temperature even when the indirect outside air cooler is operated at the maximum cooling capacity. Snow and ice air conditioning system.   The control device uses each mode of a first mode in which the indirect outside air cooler is operated alone, and a second mode in which the indirect outside air cooler and the snow / ice cold water cooler are operated in combination. 3. The snow / ice utilization air conditioning system according to claim 2, wherein the snow / ice cold water cooler is controlled.   The control device performs control to switch to the second mode when the supply air temperature cannot be maintained at a set temperature even when the indirect outside air cooler is operated at the maximum cooling capacity during operation in the first mode. The snow / ice-use air conditioning system according to claim 4. A general air conditioner that is a refrigerating air conditioner having a compressor;
In the mode in which the general air conditioner is also operated when the supply air temperature cannot be maintained at a set value even when the snow and ice chilled water cooler is operated at the maximum cooling capacity during operation in the second mode. 6. The snow / ice-use air conditioning system according to claim 5, wherein control for switching to a third mode is performed.