WO2019167248A1 - Air-conditioning system, use-side unit, control device, and control method - Google Patents

Abstract

This air-conditioning system is provided with: a refrigerant circuit in which a compressor, a heat-source-side heat-exchanger, an expansion unit, and an intermediate heat-exchanger for exchanging heat between a refrigerant and a heat medium are connected by refrigerant piping, the refrigerant circuit having the refrigerant flowing therethrough; a heat-medium circuit in which a pump, the intermediate heat-exchanger, and a use-side heat-exchanger are connected by heat-medium piping, the heat-medium circuit having the heat medium flowing therethrough; and a control device having a heat-storage mode in which hot or cold energy of the heat medium is stored using the use-side heat-exchanger or the heat-medium piping while the compressor is operating and a use mode in which the hot or cold energy stored in the heat-storage mode is used.

Description

Air conditioning system, user side unit, control device and control method

The present invention relates to an air conditioning system including an intermediate heat exchanger for exchanging heat between a refrigerant and a heat medium, a use side unit provided in the air conditioning system, a control device provided in the air conditioning system, and a control method.

Conventionally, there is known an air conditioning system that supplies hot or cold generated by a heat source side unit to a use side unit. In a building having a large area to be air-conditioned, a multi-room type air conditioning system in which a plurality of usage-side units are connected to one heat source side unit is generally introduced. Here, from the viewpoint of energy saving and construction, a building multi-air conditioner that circulates refrigerant to the room is widely used. On the other hand, from the viewpoint of global warming prevention, an air conditioning system that uses a heat medium such as water to supply hot or cold heat to an indoor unit and uses a small amount of refrigerant has been proposed (see, for example, Patent Document 1).

Patent Document 1 discloses a refrigeration cycle apparatus that transports hot or cold generated by an outdoor unit to an indoor unit using a heat medium such as water or antifreeze via a branch unit having an intermediate heat exchanger. . Patent Document 1 also discloses a refrigeration cycle apparatus in which cold heat and warm heat are stored in a heat storage tank provided on the roof of a building.

JP 2003-343936 A

However, the refrigeration cycle apparatus disclosed in Patent Document 1 requires a separate heat storage tank in order to store cold or warm heat.

The present invention has been made to solve the above-described problems, and is an air conditioning system that can store cold or heat without a heat storage tank, a use side unit provided in the air conditioning system, a control device provided in the air conditioning system, and A control method is provided.

An air conditioning system according to the present invention includes a compressor, a heat source side heat exchanger, an expansion unit, an intermediate heat exchanger that exchanges heat between the refrigerant and the heat medium, connected by a refrigerant pipe, a refrigerant circuit through which the refrigerant flows, a pump When the intermediate heat exchanger and the use side heat exchanger are connected by the heat medium pipe and the heat medium circuit through which the heat medium flows and the compressor is operating, the use side heat exchanger or the heat medium pipe is used. And a control device having a heat storage mode for storing the heat or cold of the heat medium, and a use mode for using the heat or cold stored in the heat storage mode.

According to the present invention, the control device has a heat storage mode and a use mode. In the heat storage mode, the air conditioning system can store cold or warm heat inside the use side heat exchanger or the heat medium pipe. Thus, the air conditioning system can store cold or warm heat without a heat storage tank.

It is a schematic diagram which shows the air conditioning system 100 which concerns on Embodiment 1 of this invention. It is a schematic diagram which shows the air conditioning system 100 which concerns on the 1st modification of Embodiment 1 of this invention. It is a circuit diagram which shows the air conditioning system 100 which concerns on Embodiment 1 of this invention. It is a hardware block diagram which shows the physical structure of the control apparatus 50 which concerns on Embodiment 1 of this invention. It is a block diagram which shows the functional structure of the control apparatus 50 which concerns on Embodiment 1 of this invention. It is a flowchart which shows the recognition operation | movement of the vacancy of the air conditioning system 100 which concerns on Embodiment 1 of this invention. It is a flowchart which shows the freeze prevention operation | movement of the heat medium of the air conditioning system 100 which concerns on Embodiment 1 of this invention. It is a flowchart which shows the operation | movement of the frame heat storage of the air conditioning system 100 which concerns on Embodiment 1 of this invention. It is a circuit diagram which shows the flow of a thermal medium in case only the utilization side unit 2a of the air conditioning system 100 which concerns on Embodiment 1 of this invention is set to an empty room. It is a circuit diagram which shows the flow of a heat medium when the utilization side units 2a and 2b of the air conditioning system 100 which concern on Embodiment 1 of this invention are set to the empty room. It is a circuit diagram which shows the air conditioning system 100 which concerns on the 2nd modification of Embodiment 1 of this invention. It is a circuit diagram which shows the air conditioning system 100 which concerns on Embodiment 2 of this invention. It is a circuit diagram which shows the air conditioning system 100 which concerns on the modification of Embodiment 2 of this invention. It is a block diagram which shows the control apparatus 50 which concerns on Embodiment 3 of this invention. It is a flowchart which shows the automatic recognition operation | movement of the vacancy of the air conditioning system 100 which concerns on Embodiment 3 of this invention. It is a flowchart which shows the operation | movement of the frame heat storage of the air conditioning system 100 which concerns on Embodiment 4 of this invention. It is a flowchart which shows the operation | movement of the energy-saving control of the air conditioning system 100 which concerns on Embodiment 6 of this invention. It is a flowchart which shows the operation | movement of the computer room protection control of the air conditioning system 100 which concerns on Embodiment 7 of this invention.

Embodiment 1 FIG.
Hereinafter, embodiments of an air conditioning system and a usage-side unit according to the present invention will be described with reference to the drawings. FIG. 1 is a schematic diagram showing an air conditioning system 100 according to Embodiment 1 of the present invention. As shown in FIG. 1, for example, a heat source side unit 1 that is an outdoor unit, a plurality of usage side units 2 a, 2 b, 2 c, and 2 d that adjust air in an air-conditioned space such as a room, and a heat source side unit 1 The relay unit 3 installed in the non-air-conditioned space 8 or the like that is not the object of harmony is provided, and a control device 50 that controls them. The heat source side unit 1 and the relay unit 3 are connected by two refrigerant pipes 4 to form a refrigerant circuit through which a two-phase changing refrigerant or a supercritical refrigerant flows. The relay unit 3 and the use side units 2a, 2b, 2c, and 2d are connected by two heat medium pipes 5 to form a heat medium circuit through which a heat medium such as water, brine, or antifreeze liquid flows. Thus, the construction of the air conditioning system 100 is facilitated by using two pipes.

The heat source unit 1 is usually installed in an outdoor space 6 that is an external space of a building 9 such as a building. The use side units 2a, 2b, 2c, and 2d are installed at positions in the indoor space 7 such as a living room inside a building 9 such as a building where heated or cooled heat medium is delivered. The relay unit 3 is configured as a separate housing from the heat source side unit 1 and the use side units 2a, 2b, 2c, and 2d, and is connected by the refrigerant pipe 4 and the heat medium pipe 5, and is connected to the outdoor space 6 and the indoor space. It is installed in a place different from the space 7. The relay unit 3 is installed in a non-air-conditioned space 8 such as a ceiling, which is a space different from the indoor space 7 in the interior of the building 9. In addition, the relay unit 3 may be installed in a common part provided with an elevator or the like.

The relay unit 3 is composed of one parent relay unit 3a and two child relay units 3b. Thereby, a plurality of child relay units 3b (1) and 3b (2) can be connected to one parent relay unit 3a. In the first embodiment, there are three connection pipes between the parent relay unit 3a and the child relay unit 3b.

FIG. 2 is a schematic diagram showing an air conditioning system 100 according to a first modification of the first embodiment of the present invention. As shown in FIG. 2, the number of relay units 3 may be one. When the number of usage- side units 2a, 2b, 2c, and 2d connected is small, the number of relay units 3 can be reduced.

In the first embodiment, the heat source side unit 1 is illustrated as being installed in the outdoor space 6 outside the building 9, but is installed in a closed space such as a machine room provided with a ventilation opening. It may be installed inside the building 9, and exhaust heat may be exhausted outside the building 9 by an exhaust duct, or it may be installed inside the building 9 as a water-cooled heat source side unit 1. . Moreover, although the case where the use side units 2a, 2b, 2c, and 2d are of the ceiling cassette type is illustrated, the use side units 2a, 2b, 2c, and 2d are like a ceiling embedded type or a ceiling hanging type. As long as it is connected to the indoor space 7 directly or using a duct or the like and can supply heated air or cooled air to the indoor space 7. The relay unit 3 may be arranged in the vicinity of the heat source side unit 1, but in order to reduce the energy for transferring the heat medium and save energy, the relay unit 3 and the use side units 2 a, 2 b, 2 c, 2 d and It is desirable that the distance of is shorter. In the first embodiment, a case where four usage- side units 2a, 2b, 2c, and 2d are connected to one heat-source-side unit 1 is illustrated, but the number of heat-source-side units 1 is two. The number of use side units 2a, 2b, 2c, and 2d may be one to three or five or more.

(Heat source side unit 1)
FIG. 3 is a circuit diagram showing the air conditioning system 100 according to Embodiment 1 of the present invention. As shown in FIG. 3, the heat source side unit 1 includes a compressor 10, a flow path switching device 11, a heat source side heat exchanger 12, an accumulator 17, and a heat source side flow path adjustment unit 13.

The compressor 10 compresses the sucked refrigerant and discharges it in a high temperature and high pressure state. The compressor 10 has a discharge side connected to the flow path switching device 11 and a suction side connected to the accumulator 17. The compressor 10 is, for example, an inverter compressor whose capacity can be controlled. The flow path switching device 11 is, for example, a four-way valve, and switches the flow direction of the refrigerant according to the operation mode. When the operation mode is the cooling operation, the flow path switching device 11 connects the discharge side of the compressor 10 and the heat source side heat exchanger 12, and connects the heat source side flow path adjustment unit 13 and the suction side of the accumulator 17. To do. Further, when the operation mode is the heating operation, the flow path switching device 11 connects the discharge side of the compressor 10 and the heat source side flow path adjustment unit 13, and connects the heat source side heat exchanger 12 and the suction side of the accumulator 17. Connect. In addition, although the flow-path switching apparatus 11 has illustrated about the case where it is a four-way valve, you may be comprised by combining a two-way valve or a three-way valve.

The heat source side heat exchanger 12 is a plate type heat exchanger that exchanges heat between a refrigerant flowing in the plate and a heat medium such as water or antifreeze flowing in the plate. One of the heat source side heat exchangers 12 is connected to the flow path switching device 11, and the other is connected to the high-pressure side refrigerant pipe 4 via the heat source side flow path adjustment unit 13. The heat source side heat exchanger 12 acts as a condenser during the cooling operation, and acts as an evaporator during the heating operation. Note that a heat source side blower (not shown) may be provided in the vicinity of the heat source side heat exchanger 12. Thereby, condensation and evaporation of the heat medium of the heat source side heat exchanger 12 can be promoted. In addition, the heat source side heat exchanger 12 is not limited to a plate-type heat exchanger, and may be any configuration that can dissipate heat or absorb heat.

The accumulator 17 stores surplus refrigerant that is the difference between the refrigerant that flows during the heating operation and the refrigerant that flows during the cooling operation. In addition, the accumulator 17 stores surplus refrigerant generated by an excessive change in operation, such as a change in the number of operating units 2a, 2b, 2c, and 2d. One of the accumulators 17 is connected to the suction side of the compressor 10 and the other is connected to the flow path switching device 11. The accumulator 17 may be omitted.

The heat source side flow path adjustment unit 13 makes the flow of the refrigerant flowing from the heat source side unit 1 to the relay unit 3 in a certain direction in both the cooling operation and the heating operation, and the first check valve 13b. , A second check valve 13c, a third check valve 13a, and a fourth check valve 13d. The first check valve 13b is provided in a pipe connecting the flow path switching device 11 and the high-pressure side refrigerant pipe 4, and allows the refrigerant to flow from the flow path switching apparatus 11 toward the high-pressure side refrigerant pipe 4. . The second check valve 13 c is provided in a pipe connecting the heat source side heat exchanger 12 and the low pressure side refrigerant pipe 4, and flows the refrigerant flowing from the low pressure side refrigerant pipe 4 toward the heat source side heat exchanger 12. Allow. The third check valve 13 a is provided in a pipe connecting the heat source side heat exchanger 12 and the high pressure side refrigerant pipe 4, and flows the refrigerant flowing from the heat source side heat exchanger 12 toward the high pressure side refrigerant pipe 4. Allow. The fourth check valve 13d is provided in a pipe connecting the flow path switching device 11 and the low-pressure side refrigerant pipe 4, and allows the refrigerant to flow from the low-pressure side refrigerant pipe 4 toward the flow path switching apparatus 11. . The heat source side flow path adjustment unit 13 may be omitted.

(Use side units 2a, 2b, 2c, 2d)
The use- side units 2a, 2b, 2c, and 2d are arranged at positions where cooling air or heating air can be supplied in an indoor space 7 that is a space inside the building 9 such as a living room. Thereby, the use side units 2a, 2b, 2c, and 2d supply the cooling air or the heating air to the indoor space 7 that is the air-conditioning target space. A remote controller (not shown) is connected to the use side units 2a, 2b, 2c, and 2d by wire or wireless, and when the user operates the remote control, the use side units 2a, 2b, 2c, A predetermined signal is transmitted to 2d. Each utilization side unit 2a, 2b, 2c, 2d has utilization side heat exchanger 26a, 26b, 26c, 26d and utilization side air blower 20a, 20b, 20c, 20d, respectively.

The use side heat exchangers 26 a, 26 b, 26 c, and 26 d exchange heat between the air that is the load heat medium supplied from the use side blowers 20 a, 20 b, 20 c, and 20 d and the heat medium to form the indoor space 7. Supply as air for cooling or air for heating. The use side heat exchangers 26a, 26b, 26c, and 26d are connected to the relay unit 3 through the refrigerant pipe 4, respectively. The use side heat exchangers 26a, 26b, 26c, and 26d function as an evaporator during the cooling operation, and function as a condenser during the heating operation. The use side blowers 20a, 20b, 20c, and 20d send room air to the use side heat exchangers 26a, 26b, 26c, and 26d. Thereby, condensation or evaporation of the heat medium of the use side heat exchangers 26a, 26b, 26c, and 26d can be promoted. If the use side heat exchangers 26a, 26b, 26c, and 26d use radiant heat, the use side blowers 20a, 20b, 20c, and 20d can be omitted. An indoor temperature sensor 39 for detecting the indoor temperature is provided in the room where the use side units 2a, 2b, 2c, and 2d are installed.

(Relay unit 3)
The relay unit 3 includes a housing different from the heat source side unit 1 and the plurality of usage side units 2a, 2b, 2c, and 2d, and can be installed at a position different from the outdoor space 6 and the indoor space 7. The relay unit 3 is connected to the heat source unit 1 via the high-pressure side refrigerant pipe 4 and the low-pressure side refrigerant pipe 4, and is connected to each usage- side unit 2 a, 2 b, 2 c, 2 d via the heat medium pipe 5. ing. The relay unit 3 distributes the cold heat or hot heat supplied from the heat source side unit 1 to the use side units 2a, 2b, 2c, 2d. As described above, the relay unit 3 includes the parent relay unit 3a and the child relay unit 3b.

The parent relay unit 3a includes a gas-liquid separator 14 and an expansion part 16e. The gas-liquid separator 14 separates the high-pressure gas-liquid two-phase refrigerant supplied from the heat source side unit 1 into a liquid refrigerant and a gas refrigerant. The gas-liquid separator 14 is installed at the inlet of the relay unit 3 and connected to the heat source unit 1 via the high-pressure side refrigerant pipe 4. The expansion part 32 consists of an electronic expansion valve whose opening degree can be changed, for example, and decompresses the refrigerant to expand it. Incidentally, if the CO ₂ refrigerant is used, since the supercritical cycle, the radiator for cooling the refrigerant, the refrigerant does not liquefy. For this reason, heating operation is carried out in principle. At this time, in the gas-liquid separator 14, the gas refrigerant flows out to the intermediate heat exchanger 15a.

The child relay unit 3b includes intermediate heat exchangers 15a, 15b, child expansion portions 16a, 16b, 16c, 16d, pumps 21a, 21b, flow path switching valves 22a, 22b, 22c, 22d, 23a, 23b, 23c, 23d, Stop valves 24a, 24b, 24c, 24d, bypass circuits 27a, 27b, 27c, 27d and flow rate adjusting valves 25a, 25b, 25c, 25d are provided. The intermediate heat exchangers 15a and 15b are heat exchangers that exchange heat between the refrigerant and the heat medium. In the first embodiment, the case where two of the intermediate heat exchanger 15a for heating and the intermediate heat exchanger 15b for cooling are installed is illustrated, but only one of heating and cooling is performed. In this case, only one intermediate heat exchanger 15a, 15b is required. In this case, since it is not necessary to flow the heat medium to the separate intermediate heat exchangers 15a and 15b during the freeze prevention operation, the flow path can be simplified. Further, a plurality of heating intermediate heat exchangers 15a and cooling intermediate heat exchangers 15b may be provided.

Four child expansion portions 16a, 16b, 16c, and 16d are provided, for example, which are electronic expansion valves whose opening degree can be changed, and expand the refrigerant by decompressing the refrigerant. The pumps 21a and 21b are provided on the downstream side of the intermediate heat exchangers 15a and 15b, and transfer the heat medium. The flow path switching valves 22a, 22b, 22c, 22d, 23a, 23b, 23c, and 23d are composed of three-way valves and the like, and the inlet-side flow paths and the outlet-side flow paths of the respective use side heat exchangers 26a, 26b, 26c, and 26d. The flow path switching valves 22a, 22b, 22c and 22d switch the outlet side flow path between the intermediate heat exchangers 15a and 15b, and the flow path switching valves 23a, 23b, 23c and 23d. Switches the inlet-side flow path.

In the first embodiment, the flow path switching valves 22a, 22b, 22c, and 22d switch the outlet side flow path between the intermediate heat exchangers 15a and 15b, and the flow path switching valves 23a, 23b, 23c, and 23d are intermediate heat. The inlet-side flow path is switched between the exchangers 15a and 15b. The flow path switching valves 22a, 22b, 22c, 22d, 23a, 23b, 23c, and 23d may be ones that switch a three-way flow path such as a three-way valve, or a combination of two on-off valves that switch a two-way flow path. May be good. The flow path switching valves 22a, 22b, 22c, 22d, 23a, 23b, 23c, and 23d change the flow rate of a three-way flow path such as a stepping motor drive type mixing valve or change the flow rate of a two-way flow path. A combination of two electronic expansion valves or the like may be used. Thereby, the water hammer by the sudden opening and closing of a flow path can be suppressed.

The flow path switching valves 22a, 22b, 22c, 22d, 23a, 23b, 23c, 23d, the stop valves 24a, 24b, 24c, 24d and the flow rate adjusting valves 25a, 25b, 25c, 25d are each used side heat exchangers. The case where one is connected to each of 26a, 26b, 26c, and 26d is illustrated, but a plurality of each of the use side heat exchangers 26a, 26b, 26c, and 26d may be connected. In this case, the flow path switching valves 22a, 22b, 22c, 22d, 23a, 23b, 23c, 23d, stop valves 24a, 24b, 24c, 24d connected to the same use side heat exchangers 26a, 26b, 26c, 26d. The flow rate adjusting valves 25a, 25b, 25c, and 25d may be operated in the same manner.

Stop valves 24 a, 24 b, 24 c and 24 d are provided in the heat medium circuit and block the flow of the heat medium flowing through the heat medium pipe 5. The bypass circuits 27a, 27b, 27c, and 27d connect the inlet side and the outlet side of the use side heat exchangers 26a, 26b, 26c, and 26d, and bypass the heat medium. The flow rate adjusting valves 25a, 25b, 25c, and 25d are three-way valves or the like, and switch whether the heat medium flows to the use side heat exchangers 26a, 26b, 26c, and 26d or to the bypass circuits 27a, 27b, 27c, and 27d. .

Here, the refrigerant circuit includes the compressor 10, the flow path switching device 11, the heat source side heat exchanger 12, the expansion part 16e, the gas-liquid separator 14, the intermediate heat exchangers 15a and 15b, and the child expansion parts 16a, 16b, 16c, 16d is connected by the refrigerant | coolant piping 4. The refrigerant flowing in the refrigerant circuit includes single refrigerants such as R-22 and R-134a, pseudo-azeotropic mixed refrigerants such as R-410A and R-404A, non-azeotropic mixed refrigerants such as R-407C, A refrigerant having a relatively low global warming coefficient such as CF ₃ CF═CH ₂ containing a double bond or a mixture thereof, or a natural refrigerant such as CO ₂ or propane can be used.

One heat medium circuit includes an intermediate heat exchanger 15a, a pump 21a, flow path switching valves 22a, 22b, 22c, and 22d, stop valves 24a, 24b, 24c, and 24d, and use side heat exchangers 26a, 26b, 26c, and 26 d, flow rate adjustment valves 25 a, 25 b, 25 c, 25 d and flow path switching valves 23 a, 23 b, 23 c, 23 d are connected by a heat medium pipe 5. Further, another heat medium circuit includes an intermediate heat exchanger 15b, a pump 21b, flow path switching valves 23a, 23b, 23c, 23d, stop valves 24a, 24b, 24c, 24d, use side heat exchangers 26a, 26b, 26c, 26d, the flow rate adjusting valves 25a, 25b, 25c, and 25d and the flow path switching valves 22a, 22b, 22c, and 22d are connected by the heat medium pipe 5 to constitute a heat medium circuit. In addition, each utilization side heat exchanger 26a, 26b, 26c, 26d is provided in parallel with respect to the two intermediate heat exchangers 15a, 15b, respectively, and each constitutes a heat medium circuit. The heat medium flowing through the heat medium circuit is water or brine.

The slave relay unit 3b includes first heat medium temperature sensors 31a and 31b, second heat medium temperature sensors 32a and 32b, third heat medium temperature sensors 33a, 33b, 33c, and 33d, and a fourth heat medium. It has temperature sensors 34a, 34b, 34c, 34d, a fifth temperature sensor 35, a sixth temperature sensor 37, a seventh temperature sensor 38, and a pressure sensor 36. The first heat medium temperature sensors 31a and 31b detect the temperature of the heat medium on the outlet side of the intermediate heat exchangers 15a and 15b. The second heat medium temperature sensors 32a and 32b detect the temperature of the heat medium on the inlet side of the intermediate heat exchangers 15a and 15b.

The third heat medium temperature sensors 33a, 33b, 33c, 33d detect the temperature of the heat medium on the inlet side during cooling of the use side heat exchangers 26a, 26b, 26c, 26d. The fourth heat medium temperature sensors 34a, 34b, 34c, 34d detect the temperature of the heat medium on the outlet side during cooling of the use side heat exchangers 26a, 26b, 26c, 26d. The fifth temperature sensor 35 detects the temperature of the refrigerant on the outlet side of the intermediate heat exchanger 15a. The pressure sensor 36 detects the pressure of the refrigerant on the outlet side of the intermediate heat exchanger 15a. The sixth temperature sensor 37 detects the temperature of the refrigerant on the inlet side of the intermediate heat exchanger 15b. The seventh temperature sensor 38 detects the temperature of the refrigerant on the outlet side of the intermediate heat exchanger 15b. As these temperature sensor and pressure sensor 36, various thermometers, temperature sensors, pressure gauges, pressure sensors 36, or the like are used.

The flow rate adjusting valves 25a, 25b, 25c, 25d, the third heat medium temperature sensors 33a, 33b, 33c, 33d, and the fourth heat medium temperature sensors 34a, 34b, 34c, 34d are provided inside the relay unit 3. Although illustrated about the case where it is installed, it is not restricted to this. For example, the flow rate adjusting valves 25a, 25b, 25c, and 25d, the third heat medium temperature sensors 33a, 33b, 33c, and 33d, and the fourth heat medium temperature sensors 34a, 34b, 34c, and 34d are used on the use side heat exchanger 26a, It may be installed in the vicinity of 26b, 26c, 26d, that is, in or near the use side units 2a, 2b, 2c, 2d.

(Heat load)
Next, the heat load in each of the use side heat exchangers 26a, 26b, 26c, and 26d will be described. Each heat load of use side heat exchanger 26a, 26b, 26c, 26d is represented by (1) Formula. The heat load is determined by multiplying the flow rate, density, constant pressure specific heat of the heat medium, and the temperature difference between the heat medium at the inlet and outlet of the use side heat exchangers 26a, 26b, 26c, 26d. Here, Vw is the flow rate of the heat medium, ρw is the density of the heat medium, Cpw is the constant pressure specific heat of the heat medium, Tw is the temperature of the heat medium, subscript in is the inlet of the use side heat exchangers 26a, 26b, 26c, 26d. The value of the heat medium on the side, and the subscript out indicates the value of the heat medium on the outlet side of the use side heat exchangers 26a, 26b, 26c, and 26d.

... (1)

From the equation (1), when the flow rate of the heat medium flowing to the use side heat exchangers 26a, 26b, 26c, and 26d is constant, according to the change of the heat load in the use side heat exchangers 26a, 26b, 26c, and 26d, The temperature difference at the entrance and exit of the heat medium changes. Therefore, the flow rate adjusting valves 25a, 25b, 25c, and 25d are controlled so as to approach the predetermined target value with the temperature difference between the inlet and outlet of the use side heat exchangers 26a, 26b, 26c, and 26d as a target. Thereby, an excess heat medium flows into bypass circuits 27a, 27b, 27c, and 27d, and the flow volume which flows into use side heat exchangers 26a, 26b, 26c, and 26d can be controlled. The target value of the temperature difference between the inlet side and the outlet side of the use side heat exchangers 26a, 26b, 26c, and 26d is set to 5 ° C., for example.

In the first embodiment, the case where the flow rate adjustment valves 25a, 25b, 25c, and 25d are mixing valves installed on the downstream side of the use side heat exchangers 26a, 26b, 26c, and 26d has been described as an example. However, it may be a three-way valve installed on the upstream side of the use side heat exchangers 26a, 26b, 26c, and 26d.

The heat medium that has undergone heat exchange in the use- side heat exchangers 26a, 26b, 26c, and 26d and the heat medium that has passed through the bypass circuits 27a, 27b, 27c, and 27d without heat exchange and without temperature change. , And then merge at the junction. Formula (2) is established at the junction. Here, Twin and Twout are the heat medium temperatures on the inlet side and the outlet side of the use side heat exchangers 26a, 26b, 26c, and 26d, Vw is the flow rate of the heat medium flowing into the flow rate adjusting valves 25a, 25b, 25c, and 25d, Vwr is the flow rate of the heat medium flowing into the use side heat exchangers 26a, 26b, 26c, and 26d, and Tw is the heat medium that flows through the use side heat exchangers 26a, 26b, 26c, and 26d and the bypass circuits 27a, 27b, 27c, This represents the temperature of the heat medium after the heat medium that has flowed to 27d has joined.

... (2)

From equation (2), the heat exchangers 26a, 26b, 26c, and 26d on the use side heat exchangers exchange heat and the bypass circuits 27a, 27b, 27c, and 27d without heat exchange and temperature changes. When the heat medium that has passed through is joined, the temperature of the heat medium approaches the temperature on the inlet side of the use side heat exchangers 26a, 26b, 26c, and 26d by the amount of flow that bypasses the temperature difference of the heat medium. For example, the total flow rate is 20 L / min, the heat medium inlet temperature of the use side heat exchangers 26a, 26b, 26c, 26d is 7 ° C., the outlet temperature is 13 ° C., the use side heat exchangers 26a, 26b, 26c, 26d side When the flow rate that flows through is 10 L / min, the temperature after the subsequent merging is 10 ° C. from the equation (2).

The heat medium that passes through the use side units 2a, 2b, 2c, 2d or the bypass circuits 27a, 27b, 27c, 27d and passes through the flow path switching valves 22a, 22b, 22c, 22d is subjected to intermediate heat exchange. Flows into the containers 15a and 15b. At this time, if the heat exchange amount of the intermediate heat exchangers 15a and 15b does not change, the temperature difference between the heat mediums on the inlet side and the outlet side becomes substantially the same due to heat exchange in the intermediate heat exchanger 15a or 15b. For example, the temperature difference of the heat medium between the inlet side and the outlet side of the intermediate heat exchanger 15a or 15b is 6 ° C., and initially the temperature of the heat medium at the inlet side of the intermediate heat exchanger 15a or 15b is 13 ° C. Suppose that the temperature of the heat medium on the outlet side is 7 ° C. Then, it is assumed that the heat load in the use side heat exchangers 26a, 26b, 26c, and 26d decreases, and the temperature of the heat medium on the inlet side of the intermediate heat exchanger 15a or 15b decreases to 10 ° C. Then, if nothing is done, the intermediate heat exchanger 15a or 15b performs approximately the same amount of heat exchange, so that the heat medium flows out from the intermediate heat exchanger 15a or 15b at 4 ° C., and this is repeated. The temperature of the heat medium will drop.

Therefore, the pumps 21a, 21b are changed according to the change in the heat load of the use side heat exchangers 26a, 26b, 26c, 26d so that the temperature of the heat medium on the outlet side of the intermediate heat exchanger 15a or 15b approaches the target value. Change the rotation speed. As a result, when the heat load decreases, the rotation speed of the pumps 21a and 21b decreases to save energy, and when the heat load increases, the rotation speed of the pumps 21a and 21b increases and the flow rate Vw of the heat medium increases. Can be increased.

The pump 21b operates when a cooling load or a dehumidifying load is generated in any of the use side heat exchangers 26a, 26b, 26c, and 26d. In any of the use side heat exchangers 26a, 26b, 26c, and 26d, the pump 21b operates. If there is no cooling load or dehumidifying load, the operation is stopped. The pump 21a operates when a heating load is generated in any of the usage side heat exchangers 26a, 26b, 26c, and 26d, and in any of the usage side heat exchangers 26a, 26b, 26c, and 26d. Stop when there is no heating load.

(Control device 50)
In the first embodiment, a case where there is one control device 50 will be described, but the control device 50 is separated into a heat source side control device 50a and a relay side control device 50b as shown in FIG. Also good. In this case, the heat source side control device 50a controls the heat source side unit 1 so as to function as an outdoor unit, and the relay side control device 50b controls devices constituting the relay unit 3. The heat source side control device 50a and the relay side control device 50b are composed of a microcomputer, an electric circuit, and the like, and can communicate with each other. The relay side control device 50b may be communicably connected to a remote controller, another air conditioner connected to the network, the heat source side unit 1, and the usage side units 2a, 2b, 2c, 2d. The heat source side control device 50 a and the relay side control device 50 b may be connected to a centralized controller that controls the entire air conditioning system 100.

Further, the function of the relay side control device 50b may be shared with any one of the heat source side unit 1, the use side units 2a, 2b, 2c, and 2d, the centralized controller, the remote controller, or another air conditioner connected to the network. Here, the centralized controller manages the heat source side unit 1 and the usage side units 2a, 2b, 2c, and 2d, and the remote controller is provided in the indoor space 7 and uses the room temperature information instructed by the user as the heat source side unit 1 and the usage side unit. Transmit to the side units 2a, 2b, 2c, 2d. Information from the remote controller may be transmitted to the heat source side unit 1 via the heat source side control device 50a. Thus, from the viewpoint of energy saving, the heat source unit 1 and the remote controller may communicate with each other. In addition, the control apparatus 50 may be comprised with several apparatus like this Embodiment 1, and may be comprised with a single apparatus. The first embodiment is an air conditioning system 100 in which each usage- side unit 2a, 2b, 2c, 2d performs a cooling / heating mixed operation in which a cooling operation or a heating operation can be performed.

FIG. 4 is a hardware configuration diagram showing a physical configuration of the control device 50 according to Embodiment 1 of the present invention. As shown in FIG. 4, the control device 50 controls the operation of the air conditioning system 100, and includes a communication unit 54, a control determination unit 51, and a storage unit 55. The communication unit 54, the control determination unit 51, and the storage unit 55 are connected by an internal bus. The communication unit 54 is a transmission / reception circuit connected to the communication port, and transmits / receives communication via the communication port. The control determination unit 51 is, for example, a microcomputer, and stores data received by the communication unit 54 in the storage unit 55 as necessary. In addition, the control determination unit 51 reads data stored in the storage unit 55 and transmits the read data to the transmission target via the communication unit 54. The storage means 55 is a RAM that stores various data.

FIG. 5 is a block diagram showing a functional configuration of the control device 50 according to Embodiment 1 of the present invention. As illustrated in FIG. 5, the control device 50 includes an input unit 52, an output unit 53, a communication unit 54, a storage unit 55, and a control determination unit 51. Note that the function of the control device 50 may be realized by a program executed by a microcomputer. The input unit 52 acquires information typified by a set temperature set by the user. Further, the input unit 52 reads detection results of the first heat medium temperature sensors 31a, 31b and the like. The output unit 53 outputs control information for adjusting the flow rate of the heat medium flowing through the bypass circuits 27a, 27b, 27c, and 27d to the flow rate adjusting valves 25a, 25b, 25c, and 25d. The communication unit 54 communicates with devices constituting the air conditioning system 100 such as the use side units 2a, 2b, 2c, and 2d, the heat source side unit 1, and the centralized controller. For example, information such as temperature, valve opening / closing, control of the flow path control device, frequency of the compressor 10 and operation stop of the air conditioning system 100 is communicated. Here, the control device 50 has a heat storage mode and a use mode. The heat storage mode is a mode in which warm heat or cold heat of the heat medium is stored using the use side heat exchangers 26a, 26b, 26c, 26d or the heat medium pipe 5 when the compressor 10 is operating. The use mode is a mode in which warm or cold energy stored in the heat storage mode is used.

The storage means 55 includes a memory or the like, and has heat medium flow control information 55a and space information 55b. The heat medium flow control information 55 a includes a target set temperature set by the user and information necessary for heat medium flow control based on the detection result of the indoor temperature sensor 39. The information necessary for controlling the flow rate of the heat medium is, for example, the inlet temperature, outlet temperature, suction temperature, etc. of the use side units 2a, 2b, 2c, 2d. The air conditioning system 100 calculates the operating capacity of each usage side unit 2a, 2b, 2c, 2d based on the inlet temperature, outlet temperature, suction temperature, etc. of the usage side units 2a, 2b, 2c, 2d, and reaches the set temperature. Harmonize with the air. The space information 55b includes information for identifying the correspondence between the indoor space 7 and the installed use side units 2a, 2b, 2c, and 2d, and the characteristics of the installed space. Here, the information for identifying the use side units 2a, 2b, 2c, 2d is a floor plan of the indoor space 7 or a unique address for communication of the use side units 2a, 2b, 2c, 2d. The characteristic of the space is information such as that the indoor space 7 is used as a computer room, or that the room 7 is vacant in a specific time zone. In addition, the space characteristic is information such as that the temperature change of the space is within an allowable range. Note that the storage unit 55 may not be incorporated in the control device 50.

The control determination unit 51 compares the information received from the input unit 52 with the information from the storage unit 55 and the communication unit 54, and transmits the control content of each device to the output unit 53. Here, the information from the communication unit 54 is information such as temperature, valve opening / closing, flow path control device control, frequency of the compressor 10 and operation stop of the air conditioning system 100 as described above. The control determination unit 51 includes a heat storage unit 51a, a freezing suppression unit 51b, and a heat medium flow rate control unit 51c.

The heat storage means 51a is for storing, in the heat storage mode, the warm or cold energy of the heat medium in the housing when the compressor 10 is operating. In this Embodiment 1, the case where heat is stored using the use side heat exchangers 26a, 26b, 26c, and 26d is illustrated, and heat is stored in the vacant room. When the heat storage means 51a receives information from the input unit 52 that any one of the indoor spaces 7 in which the use side heat exchangers 26a, 26b, 26c, and 26d are installed is an empty room, the indoor space 7 that is an empty room. The hot or cold heat of the heat medium flowing in the use side heat exchangers 26a, 26b, 26c, and 26d installed in is stored in the empty room. In the first embodiment, the information indicating that the room is vacant is received by the heat storage means 51a via the input unit 52 by the user operating with a remote controller or the like, and stored in the storage means 55 as the spatial information 55b. The heat storage means 51a determines the availability. Here, a vacant room is a room where there is no person. Examples of vacancies include living rooms, warehouses or computer rooms. In the case of a warehouse, the upper limit value and the lower limit value (space information 55b) of the internal temperature are set in consideration of the storage state of the stored goods. In the case of a computer room, it is stored cold by being cooled more than necessary. The spatial information 55b may be set using a user interface using a centralized controller. Here, using the user interface means setting on the display device. The setting of the spatial information 55b may be a combination of a mechanical on or off state by a plurality of switches. Further, static information in the spatial information 55b may be set in advance when the air conditioning system 100 is manufactured.

The freezing suppression means 51b suppresses freezing of the heat medium by flowing the heat stored by the heat storage means 51a through the heat medium in the use mode. When the temperature of the heat medium is equal to or lower than the temperature threshold value, the anti-freezing means 51b causes the intermediate heat exchangers 15a and 15b to perform an anti-freeze operation that causes the heat stored in the heat storage means 51a to flow through the heat medium and suppress the heat medium from freezing. Let it be implemented. The flow path of the heat medium from the intermediate heat exchangers 15a, 15b to the use side heat exchangers 26a, 26b, 26c, 26d is generally installed inside the building 9, and usually the freezing temperature of the heat medium, for example, water In this case, the temperature is kept higher than 0 ° C. Here, when the compressor 10 and the pumps 21a and 21b have been stopped for a long period of time, or when the intermediate heat exchangers 15a and 15b are installed outdoors, the heat medium circuit is cooled to reach the freezing temperature. there is a possibility. In particular, since the temperature drop of the outside air is remarkable at midnight and the like, and there are many people absent, heating is not used and the stop state continues, so that the heat medium is likely to freeze. For this reason, it is necessary to perform freezing suppression for suppressing freezing of the heat medium.

Freezing suppression means 51b includes first heat medium temperature sensors 31a, 31b, second heat medium temperature sensors 32a, 32b, third heat medium temperature sensors 33a, 33b, 33c, 33d, or a fourth heat medium temperature sensor. When the detected temperature of any one of 34a, 34b, 34c, and 34d becomes equal to or lower than a preset temperature, the freeze prevention operation is performed by the intermediate heat exchangers 15a and 15b.

In the anti-freezing operation, the anti-freezing means 51b operates the pump 21a or 21b in the intermediate heat exchangers 15a and 15b to circulate the heat medium, and stirs the heat medium in the heat medium pipe 5 to thereby heat the heat medium circuit. The entire temperature can be made uniform, and the temperature of the heat medium in the part where the temperature has decreased can be raised to prevent freezing.

The first heat medium temperature sensors 31a, 31b, the second heat medium temperature sensors 32a, 32b, the third heat medium temperature sensors 33a, 33b, 33c, 33d, or the fourth heat medium temperature sensors 34a, 34b, Which of the pumps 21a and 21b is operated is changed depending on which detected temperature of 34c and 34d is equal to or lower than the set temperature. The freezing suppression means 51b operates the pump 21a when either the first heat medium temperature sensor 31a or the second heat medium temperature sensor 32a becomes a set temperature or lower. When either the first heat medium temperature sensor 31b or the second heat medium temperature sensor 32b becomes equal to or lower than the set temperature, the pump 21b is operated. Furthermore, when any of the third heat medium temperature sensors 33a, 33b, 33c, and 33d or the fourth heat medium temperature sensors 34a, 34b, 34c, and 34d falls below the set temperature, the corresponding use side heat exchange is performed. Either the pump 21a or 21b connected to the units 26a, 26b, 26c, and 26d is operated to circulate the heat medium.

Also, for example, when heating operation is performed during the day, the room temperature is higher than the outside air temperature. That is, warm heat is stored in a housing such as air, walls, and floors present in the indoor space 7. At this time, since the temperature of the indoor space 7 is higher than the temperature of the heat medium in the heat medium pipe 5 disposed in the non-air-conditioned space 8, heat exchange is performed between the air in the indoor space 7 and the heat medium. However, it is possible to prevent freezing. Therefore, in the water air-conditioning system of this embodiment, heat is stored in air in an empty room that does not need to be heated and used to prevent the heat medium from freezing. The heat storage means 51a identifies the usage- side units 2a, 2b, 2c, and 2d installed in the vacant space from the space information 55b, and the usage- side heat exchangers 26a and 26b of the usage- side units 2a, 2b, 2c, and 2d. , 26c, 26d, etc., by promoting heat exchange with the use side blowers 20a, 20b, 20c, 20d, etc., so that the heat stored in the housing such as air, walls, and floors in the indoor space 7 is transferred to the heat medium. Flow through the circuit. Thereby, it is possible to prevent the heat medium from freezing. Even if the room is not vacant during the day, there are many times when the freezing prevention time such as nighttime is likely to be vacant. By doing so, it is possible to perform an anti-freezing operation using an empty room.

When the heat medium flow control means 51c receives signals from the heat storage means 51a and the freeze suppression means 51b, the pumps 21a, 21b, the flow path switching valves 22a, 22b, 22c, 22d, 23a, 23b, 23c, 23d, the flow rate adjustment The operation of the valves 25a, 25b, 25c, 25d, the stop valves 24a, 24b, 24c, 24d and the use side blowers 20a, 20b, 20c, 20d is controlled. Specifically, it will be described later with reference to the flowchart shown in FIG.

FIG. 6 is a flowchart showing the vacancy recognition operation of the air conditioning system 100 according to Embodiment 1 of the present invention. The control device 50 executes the vacancy recognition operation constantly or at a constant cycle. As shown in FIG. 6, when the control device 50 receives information indicating that the room is vacant from the user via the input unit 52 (step ST1), the control device 50 stores the space information 55b indicating that the room is vacant in the storage means 55 ( Step ST2).

FIG. 7 is a flowchart showing the operation of preventing the freezing of the heat medium of the air conditioning system 100 according to Embodiment 1 of the present invention. As shown in FIG. 7, the freezing suppression unit 51b determines whether the temperature T1a detected by the first heat medium temperature sensor 31a is equal to or lower than the set temperature Ts (step ST11). When the temperature T1a detected by the first heat medium temperature sensor 31a is higher than the set temperature Ts, the freeze suppression means 51b determines whether the temperature T2a detected by the second heat medium temperature sensor 32a is equal to or lower than the set temperature Ts. Is determined (step ST12). When the temperature T2a detected by the second heat medium temperature sensor 32a is higher than the set temperature Ts, the freeze suppression means 51b determines whether the temperature T1b detected by the first heat medium temperature sensor 31b is equal to or lower than the set temperature Ts. Is determined (step ST13). When the temperature T1b detected by the first heat medium temperature sensor 31b is higher than the set temperature Ts, the freezing suppression means 51b determines whether the temperature T2b detected by the second heat medium temperature sensor 32b is equal to or lower than the set temperature Ts. Is determined (step ST14). When the temperature T2b detected by the second heat medium temperature sensor 32b is higher than the set temperature Ts, the control device 50 sets n = 1 (step ST16). Here, n is an identifier for identifying the usage- side units 2a, 2b, 2c, 2d. For example, the utilization side unit (1) is 2a, the utilization side unit (2) is 2b, the utilization side unit (3) is 2c, and the utilization side unit (4) is 2d, and the maximum value of n at this time is 4. . If any of the detection results of the first heat medium temperature sensors 31a and 31b or the second heat medium temperature sensors 32a and 32b is equal to or lower than the set temperature Ts in step ST11, step ST12, step ST13, and step ST14, freezing is performed. The suppression means 51b determines that the heat stored by the heat storage means 51a is used for prevention of freezing, and holds the determination result (step ST15).

The freezing suppression means 51b determines whether or not the temperature T4a detected by the fourth heat medium temperature sensor provided in the nth user side unit (n) has become equal to or lower than the set temperature Ts (step ST17). When the temperature T4a detected by the fourth heat medium temperature sensor is higher than the set temperature Ts, the freezing suppression unit 51b determines whether the temperature T4b detected by the fourth heat medium temperature sensor is equal to or lower than the set temperature Ts. (Step ST18). If the temperature T4b detected by the fourth heat medium temperature sensor is equal to or lower than the set temperature Ts, the control device 50 determines whether n is the maximum value (step ST20). If n is not the maximum value, n = n + 1. (Step ST21), the process returns to step ST17. When the fourth heat medium temperature sensors 34a, 34b, 34c, 34d are equal to or lower than the set temperature Ts in step ST17 and step ST18, the freezing suppression means 51b uses the heat stored by the heat storage means 51a for freezing prevention. (Step ST19). In step ST17, the third heat medium temperature sensors 33a, 33b, 33c, and 33d may be used instead of the fourth heat medium temperature sensors 34a, 34b, 34c, and 34d. In this case, the place where the third heat medium temperature sensors 33a, 33b, 33c, and 33d are easily frozen during the freeze prevention operation can improve the accuracy of temperature detection.

When n is the maximum value in step ST20, the freezing suppression unit 51b has all the temperatures detected by the first heat medium temperature sensors 31a, 31b and the fourth heat medium temperature sensors 34a, 34b, 34c, 34d. It is determined whether the temperature is equal to or higher than the set temperature Ts (step ST22). For example, if the amount of heat necessary for preventing freezing has already been stored in advance, the result of step ST22 is No. If the heat has not been stored, the result of step ST22 is Yes. The second heat medium temperature sensors 32a and 32b and the third heat medium temperature sensors 33a, 33b, 33c, and 33d may be used for temperature determination. When all the temperatures are equal to or higher than the set temperature Ts, the freezing suppression unit 51b stops the freezing prevention operation (step ST23).

FIG. 8 is a flowchart showing the operation of housing heat storage of the air conditioning system 100 according to Embodiment 1 of the present invention. As shown in FIG. 8, the heat storage means 51a determines whether or not the compressor 10 is operating at the current time and heat storage is required (step ST31). Whether or not heat storage is necessary is determined in step ST15, step ST19, and step ST23. When the compressor 10 is stopped or heat storage is not necessary, the control device 50 determines whether to use the stored heat (step ST32). When either step ST31 or step ST32 is YES, the control device 50 sets n = 1 (step ST33). The heat storage means 51a determines whether the usage- side units 2a, 2b, 2c, and 2d are installed in vacant rooms (step ST34).

If installed in the vacant room, the heat storage means 51a determines whether the temperatures of the use side units 2a, 2b, 2c, 2d are within an allowable temperature range stored in advance (step ST35). When the temperature is within the allowable temperature range, the heat medium flow control means 51c operates the pump 21a or 21b (step ST36). The heat medium flow control means 51c switches the flow path switching valves 22a, 22b, 22c, and 22d connected to the use side units 2a, 2b, 2c, and 2d to the heating intermediate heat exchanger 15a side, The switching valves 23a, 23b, 23c, and 23d are switched to the cooling intermediate heat exchanger 15b side (step ST37).

Thereafter, the heat medium flow control means 51c fully opens and stops the flow rate adjusting valves 25a, 25b, 25c, 25d of the use side units 2a, 2b, 2c, 2d to the use side heat exchangers 26a, 26b, 26c, 26d side. The valves 24a, 24b, 24c, and 24d are opened, and the use side fans 20a, 20b, 20c, and 20d are operated (step ST38). Then, control device 50 determines whether n is the maximum value (step ST39). If n is not the maximum value, n = n + 1 is set (step ST40), and the process returns to step ST34. If n is the maximum value, the control ends. In other words, the usage- side units 2a, 2b, 2c, and 2d are searched in order from n = 1 until the maximum value is reached. In step ST33 to step ST40 in the case of YES in step ST31, cold heat is stored in the empty room. Further, in step ST33 to step ST40 in the case of YES in step ST32, the heat stored in the housing is used. Further, the condition “use the stored cold energy” in step ST32 can be arbitrarily designated in the heat medium freezing prevention process as shown in step ST19 and step ST15 of FIG. In step ST36, both pumps 21a and 21b may be operated.

FIG. 9 is a circuit diagram showing the flow of the heat medium when only the usage-side unit 2a of the air conditioning system 100 according to Embodiment 1 of the present invention is set to an empty room. As shown in FIG. 9, when only the use side unit 2a is installed in the empty room, the heat medium is cooled by the intermediate heat exchanger 15b, and cold heat is stored in the empty room.

FIG. 10 is a circuit diagram showing the flow of the heat medium when the usage- side units 2a and 2b of the air conditioning system 100 according to Embodiment 1 of the present invention are set to vacant rooms. In step ST37, the flow path switching valves 22 and 23 are switched to the intermediate heat exchanger 15a or 15b side, but may be switched so that the heat medium having a low temperature and the heat medium having a high temperature are stirred. For example, the flow path switching valve 22 of the use side unit (n) installed in the empty room is switched to the intermediate heat exchanger 15a side, and the flow path switching valve 23 is switched to the intermediate heat exchanger 15b side. And the flow-path switching valve 22 of the utilization side unit (n + 1) installed in the empty room is switched to the intermediate heat exchanger 15b side, and the flow-path switching valve 23 is switched to the intermediate heat exchanger 15a side.

Further, the flow path switching valve 22 of the use side unit (n) installed in the vacant room is switched to the intermediate heat exchanger 15b side, and the flow path switching valve 23 is switched to the intermediate heat exchanger 15a side. And the flow-path switching valve 22 of the utilization side unit (n + 1) installed in the empty room is switched to the intermediate heat exchanger 15a side, and the flow-path switching valve 23 is switched to the intermediate heat exchanger 15b side. In this case, as shown in FIG. 10, when the use side units 2a and 2b are installed in the vacant room, the heat is stored in the use side unit 2a and the cold is stored in the use side unit 2b.

In the control method of the control device 50 according to the first embodiment, when the compressor 10 is in operation, the heating medium has a heating temperature using the use side heat exchangers 26a, 26b, 26c, 26d or the heating medium pipe 5. Alternatively, the method includes a step of storing cold energy and a step of using the stored heat or cold energy.

According to the first embodiment, the control device 50 has a heat storage mode and a use mode. In the heat storage mode, the air conditioning system 100 can store cold or warm heat inside the use side heat exchangers 26a, 26b, 26c, 26d or the heat medium pipe 5. In this way, the air conditioning system 100 can store cold or warm heat even if a separate heat storage tank is not prepared. Here, in the first embodiment, in the heat storage mode, the control device 50 uses the heat or cold that the heat medium flowing in the use side heat exchangers 26a, 26b, 26c, and 26d installed in the empty room where no person is present. Is stored in the empty room. Thus, since the heat storage place is a vacant room, that is, indoors, the heat or cold stored in the vacant room is not easily dissipated. Therefore, the utilization efficiency of the stored heat can be improved.

In the use mode, when the temperature of the heat medium detected by the heat medium temperature sensor is equal to or lower than the temperature threshold, the control device 50 suppresses freezing of the heat medium by flowing the heat stored in the heat storage mode to the heat medium. Means 51b is further provided. In this way, by preliminarily storing heat in an empty room that does not require air conditioning, freezing of the heat medium can be suppressed using the stored warm heat without starting the compressor 10. Further, by storing the cold energy, it is possible to prevent freezing and shorten the start-up time (improvement in the responsiveness of the cooling operation and the heating operation).

Conventionally, a relay unit is provided between a heat source unit and a plurality of indoor units, and heat transfer is performed between the heat source unit and the relay unit using a refrigerant, and water is transferred between the relay unit and the indoor unit using water. The system is known. The water air-conditioning system uses water to reduce the amount of refrigerant while realizing a reduction in start-up time, energy saving and construction by refrigerant control. In such a water air-conditioning system, when the outside air temperature is low, the water pipe may be frozen. Therefore, even when the operation is stopped, the pump, the compressor, the boiler, or the like is activated to suppress the freezing of the water pipe. However, since the compressor or the like is started during the freeze prevention operation, the power consumption increases. In addition, the conventional chiller system that uses the heat stored in the buffer tank to prevent freezing takes time to start the buffer tank.

On the other hand, the first embodiment can reduce power consumption because it is not necessary to start the compressor 10 when preventing freezing. In addition, since the first embodiment stores heat in the vacant room, the stored heat can be used only by starting the pumps 21a and 21b. Therefore, the startup time is short.

As another conventional technique, an air conditioner including a relay unit that connects a heat source device and a plurality of indoor units is known. The refrigerant carries heat between the heat source device and the relay unit, and water carries heat between the relay unit and each indoor unit. Refrigerant control reduces the amount of refrigerant to be used by using water while shortening the startup time, realizing energy savings and workability. In this prior art, the temperature in the heat medium circulation circuit is made uniform by moving the pump to stir the heat medium in the heat medium piping to prevent the heat medium from freezing, and the temperature of the heat medium in the part where the temperature has decreased. To prevent freezing. On the other hand, the air conditioning system 100 according to the first embodiment can store the cold in the vacant room in advance when the compressor 10 is operating, and store the heat when the temperature of the heat medium is equal to or lower than the set temperature. By performing anti-freezing operation such as applying the cooled heat to the heat medium, the effect of anti-freezing can be made higher than the conventional stirring of the heat medium by the pumps 21a and 21b.

In addition, in this Embodiment 1, although illustrated about the case where the temperature sensor is installed in the inlet side and outlet side of intermediate heat exchanger 15a, 15b, the inlet side or outlet of intermediate heat exchanger 15a, 15b The temperature sensor should just be installed in either one of the sides. Also in this case, the pumps 21a and 21b can be controlled.

(Second modification)
FIG. 11 is a circuit diagram showing an air conditioning system 100 according to a second modification of the first embodiment of the present invention. As shown in FIG. 11, in the second modification, two-way valves are used as the flow rate adjusting valves 25a, 25b, 25c, 25d, and bypass circuits 27a, 27b, 27c, 27d and stop valves 24a, 24b, 24c. 24d are omitted. In the second modification, the opening areas of the flow rate adjusting valves 25a, 25b, 25c, and 25d are controlled, and the pumps 21a and 21b are operated after the circulation path of the heat medium is secured.

The opening areas of the two-way valve flow control valves 25a, 25b, 25c, and 25d can be continuously changed by a stepping motor or the like. In this case, the same control as that of the three-way valve is possible, and the control device 50 adjusts the opening degree of the flow rate adjustment valves 25a, 25b, 25c, and 25d to the use side heat exchangers 26a, 26b, 26c, and 26d. The flow rate of the heat medium to be introduced is controlled. The control device 50 controls the temperature difference between the inlet side and the outlet side of the use side heat exchangers 26a, 26b, 26c, and 26d to be a predetermined target value, for example, 5 ° C. Then, the rotational speeds of the pumps 21a and 21b may be controlled so that the temperature on the inlet side or outlet side of the intermediate heat exchangers 15a and 15b becomes a predetermined target value.

If a two-way valve is used as the flow rate adjusting valve 25a, 25b, 25c, 25d as in the second modification, it can be used to open and close the flow path, so that the stop valves 24a, 24b, 24c, 24d are unnecessary. Thus, the air conditioning system 100 can be constructed at low cost. In addition, when a two-way valve is used as the flow rate adjusting valves 25a, 25b, 25c, and 25d as in the second modification, the third heat medium temperature sensors 33a, 33b, 33c, 33d, and the fourth heat medium are used. The temperature sensors 34a, 34b, 34c, 34d are installed in or near the relay unit 3, and the flow rate adjusting valves 25a, 25b, 25c, 25d are installed in or near the use side units 2a, 2b, 2c, 2d. It may be.

Embodiment 2. FIG.
FIG. 12 is a circuit diagram showing an air conditioning system 100 according to Embodiment 2 of the present invention. The second embodiment is different from the first embodiment in that the relay unit 18 is simplified. In the second embodiment, the same parts as those of the first embodiment are denoted by the same reference numerals, and the description thereof is omitted. The description will focus on differences from the first embodiment.

The relay unit 18 includes an intermediate heat exchanger 15, an expansion unit 16, and a pump 21. In the relay unit 3, the flow path switching valves 22a, 22b, 22c, and 22d are omitted, and a cooling only operation and a heating operation are possible instead of a cooling and heating mixed operation. The stop valves 24a, 24b, 24c, 24d, the flow rate adjusting valves 25a, 25b, 25c, 25d, the third heat medium temperature sensors 33a, 33b, 33c, 33d, and the fourth heat medium temperature sensors 34a, 34b, 34c. , 34d are provided in the use side units 2a, 2b, 2c, 2d. In the second embodiment, by omitting the structure for performing the cooling and heating mixed operation, the number of parts can be reduced and the number of the heat medium pipes 5 can be reduced. For this reason, in the process using the housing heat storage of the first embodiment, the control of the flow path switching valves 22a, 22b, 22c, and 22d becomes unnecessary, so that the control of the pump 21 and the like are simplified.

(Modification)
FIG. 13 is a circuit diagram showing an air conditioning system 100 according to a modification of the second embodiment of the present invention. As shown in FIG. 13, in the modified example, two-way valves are used as the flow rate adjusting valves 25a, 25b, 25c, 25d, and bypass circuits 27a, 27b, 27c, 27d and stop valves 24a, 24b, 24c, 24d. Is omitted. In the modification, the opening areas of the flow rate adjusting valves 25a, 25b, 25c, and 25d are controlled, and the pumps 21a and 21b are operated after the circulation path of the heat medium is secured. Also in the modified example, the same effect as in the second embodiment is obtained.

Embodiment 3 FIG.
FIG. 14 is a block diagram showing a control device 50 according to Embodiment 3 of the present invention. The third embodiment is different from the first embodiment in that the storage unit 55 stores history information 55c and permission information 55d. In the third embodiment, the same parts as those in the first embodiment are denoted by the same reference numerals, and the description thereof will be omitted. The description will focus on differences from the first embodiment.

In the third embodiment, based on the temperature rise history of the indoor space 7, the operation history of cooling or heating, etc., the vacancy of the space information 55b is estimated and the setting work by the user is saved. As shown in FIG. 14, the storage means 55 stores history information 55c and permission information 55d. The history information 55c includes information such as a history of cooling or heating operation and stop, and a history of temperature change over time. The history of operation or stop of cooling or heating is a history of the number of times cooling or heating has been performed for each of the usage- side units 2a, 2b, 2c, and 2d, and the control device 50 has a frequency of cooling or heating being performed. If there are few, I guess it is empty. Here, the low frequency means, for example, a case where only the trial operation is performed or a case where the operation is not performed. The history of temperature change over time is a history of time change in outside air temperature or time change in room temperature, etc., and the control device 50 cannot find a correlation between the time change in outside air temperature and the time change in room temperature. Guess not vacant.

For example, in a space where a person is present, even when cooling or heating is stopped, the room temperature rises due to the heat of the human body and the heat of a device such as a personal computer operated by the person. For this reason, the control apparatus 50 estimates that it is not an empty room, when the rise in indoor temperature differs from the tendency of the rise in outside air temperature. The history information 55c can improve the accuracy of estimation by storing the history of time information together. For example, it is possible to estimate the time zone or season when the room is vacant. The control device 50 can estimate that the room becomes vacant in a specific time zone or season by analyzing the tendency of the frequency of use of cooling or heating.

Permission information 55d is information related to permission for automatic recognition of vacancies. The permission information 55d is set by the user as to whether or not to allow the user to automatically recognize a vacant room without setting the permission information 55d. In the case of permission, the vacancy is automatically recognized, and in the case of prohibition, the user manually recognizes without being automatically recognized. When the permission information 55d is set by the user, the control device 50 may set permission / rejection of automatic recognition for each space in association with the space information 55b, and automatically recognizes for each use unit 2a, 2b, 2c, 2d. May be set, or automatic recognition may be set collectively for all the use side units 2a, 2b, 2c, 2d.

FIG. 15 is a flowchart showing the automatic vacancy recognition operation of the air conditioning system 100 according to Embodiment 3 of the present invention. The control device 50 executes the automatic vacancy recognition operation at all times or at a constant cycle. As illustrated in FIG. 15, the control device 50 determines whether the spatial information 55b is set by the user (step ST51). When the spatial information 55b is set, the control device 50 stores the spatial information 55b in the storage unit 55 (step ST52). When the spatial information 55b is not set or when the control device 50 stores the spatial information 55b, the control device 50 determines whether automatic recognition is permitted by the user (step ST53). If permitted, control device 50 adds permission to permission information 55d (step ST54).

If it is not permitted, or if it is added that the control device 50 is permitted, the control device 50 sets n = 1 (step ST55). Here, n is an identifier for identifying the usage- side units 2a, 2b, 2c, 2d. For example, the utilization side unit (1) is 2a, the utilization side unit (2) is 2b, the utilization side unit (3) is 2c, and the utilization side unit (4) is 2d, and the maximum value of n at this time is 4. . Then, the heat storage means 51a determines whether or not the permission information 55d of the use side units 2a, 2b, 2c, and 2d (n) is permitted (step ST56). If permitted, the heat storage means 51a determines whether the use- side units 2a, 2b, 2c, 2d (n) have a low frequency of heating or cooling (step ST57). At this time, the heat storage means 51 a refers to the history information 55 c stored in the storage means 55. When the frequency of heating or cooling is low, the heat storage means 51a has the same tendency of an increase in the indoor temperature of the indoor space 7 in which the use side units 2a, 2b, 2c, 2d (n) are installed and an increase in the outside air temperature. Is determined (step ST58). When the tendency of the rise in the indoor temperature and the rise in the outside air temperature are the same, the heat storage means 51a automatically recognizes the indoor space 7 in which the use side units 2a, 2b, 2c, 2d (n) are installed as an empty room. (Step ST59).

On the other hand, when the operation frequency is high in step ST57 or the tendency is different in step ST58, the control device 50 cancels the setting of the vacant rooms of the use side units 2a, 2b, 2c, 2d (n) (step ST62). After step ST59, it is determined whether n is the maximum value (step ST60). If n is not the maximum value, n = n + 1 is set (step ST61), and the process returns to step ST56. If n is the maximum value in step ST60, the control ends. That is, whether the indoor space 7 in which each usage- side unit 2a, 2b, 2c, 2d is installed is recognized as a vacant room until the usage- side units 2a, 2b, 2c, 2d sequentially reach the maximum value from n = 1. Is searched.

In addition, when the air conditioning system 100 is just introduced, and there is no operation history of heating or cooling in the use side units 2a, 2b, 2c, and 2d, NO is determined in step ST57 and the process may be shifted to step ST62. . Similarly, when the tendency of the temperature rise of the usage- side units 2a, 2b, 2c, 2d is unknown, the result in step ST57 is NO, and the process may proceed to step ST62. Further, the case where the space information 55b recognizes a vacant room only when both of step ST57 and step ST58 are YES is illustrated, but when either one of step ST57 or step ST58 is YES, it is empty. It may be recognized as a room.

According to the third embodiment, the indoor temperature sensor 39 that detects the temperature of the air-conditioning target space is further provided, and the control device 50 stores the history of the time change of the temperature detected by the indoor temperature sensor 39. The heat storage means 51a has a function of determining whether the air-conditioning target space is an empty room based on the history stored in the storage means 55. Further, the control device 50 further includes storage means 55 for storing the operation history of the refrigerant circuit and the heat medium circuit, and the heat storage means 51a has an air-conditioning target space based on the history stored in the storage means 55. It has a function to determine whether it is a room. The control device 50 has a function of determining whether the air-conditioning target space is vacant for each time zone based on the history stored in the storage unit 55. In this way, it is possible to automatically recognize the vacancy simply based on the operation history or the temperature change history grasped by the air conditioning system 100. For this reason, it is possible to save the user from setting up vacancies.

Embodiment 4 FIG.
FIG. 16 is a flowchart showing the operation of housing heat storage in the air conditioning system 100 according to Embodiment 4 of the present invention. The fourth embodiment is different from the first embodiment in that heat is stored using the heat medium pipe 5. In the fourth embodiment, the same parts as those in the first embodiment are denoted by the same reference numerals, and the description thereof will be omitted. The description will focus on differences from the first embodiment.

In the fourth embodiment, the heat storage means 51a stores heat in the heat medium pipe 5 connected to the use side heat exchangers 26a, 26b, 26c, and 26d that have not been subjected to heat exchange in advance, and freeze prevention means 51b. Controls freezing using the stored heat. The heat medium flow control means 51c is configured so that the heat medium flows through the bypass circuits 27a, 27b, 27c, and 27d connected to the use side units 2a, 2b, 2c, and 2d installed in the vacant rooms. , 25b, 25c, 25d are fully opened to the bypass circuits 27a, 27b, 27c, 27d side. The opening degree of the flow rate adjusting valves 25a, 25b, 25c, 25d is adjusted so as to satisfy the expression (2).

The heat medium flow control means 51c reduces the rotation speed of the pumps 21a, 21b and adjusts the opening degree of the flow rate adjustment valves 25a, 25b, 25c, 25d connected to the use side units 2a, 2b, 2c, 2d. By this, as shown in (1) type | formula and (2) type | formula, a cooling capability or a heating capability can be adjusted. Thereby, the heat medium on the outlet side of the bypass circuits 27a, 27b, 27c, and 27d is reheated by the intermediate heat exchangers 15a and 15b, and the average temperature of the heat medium is prevented from being biased to the target temperature. it can.

The heat storage means 51a determines whether the use side units 2a, 2b, 2c, 2d are in operation, and then determines whether the use side units 2a, 2b, 2c, 2d are installed in the vacant room. And the heat storage means 51a stores heat inside the heat medium pipe 5 when the use side units 2a, 2b, 2c, 2d are stopped and there is a person in the room. Moreover, when the use side units 2a, 2b, 2c, 2d are stopped and there is no person in the room, the heat storage means 51a stores heat in the empty room.

In FIG. 16, steps ST31 to ST40 are the same as steps ST31 to ST40 shown in FIG. As shown in FIG. 16, after the controller 50 sets n = 1 in step ST33, the heat storage means 51a determines whether the use side units 2a, 2b, 2c, 2d (n) are operating (step ST71). ). When the use side units 2a, 2b, 2c, 2d (n) are not operating, the heat storage means 51a determines whether the use side units 2a, 2b, 2c, 2d are set to vacant rooms (step ST34). When the use side units 2 a, 2 b, 2 c, 2 d are not set to empty rooms, the heat storage means 51 a stores heat inside the heat medium pipe 5.

The heat medium flow control means 51c operates the pump 21a or 21b. The heat medium flow rate adjustment means fully opens the flow rate adjustment valves 25a, 25b, 25c, 25d connected to the use side units 2a, 2b, 2c, 2d (n) to the bypass circuits 27a, 27b, 27c, 27d side. (Step ST73). In step ST72 and step ST73 in the case of YES in step ST31, the heat storage means 51a bypasses the bypass circuit 27a, without changing the indoor temperature of the air-conditioned space in which the use side units 2a, 2b, 2c, 2d are installed. Cold heat at the inlet side of the bypass circuits 27a, 27b, 27c, 27d is stored in the heat medium pipe 5 at the outlet side of 27b, 27c, 27d. In step ST72 and step ST73 in the case of YES in step ST32, the freezing suppression means 51b bypasses the bypass circuit 27a without changing the room temperature of the air-conditioned space in which the use side units 2a, 2b, 2c, 2d are installed. , 27b, 27c, and 27d.

Here, although the heat storage means 51a has illustrated about the case where heat storage is carried out when the air-conditioning space is not set to the vacant space, also when it is set to the vacant space, cold heat is stored inside the heat medium pipe 5. Alternatively, cold energy stored in the heat medium pipe 5 may be used. The fourth embodiment can also be applied to a configuration that does not have the bypass circuits 27a, 27b, 27c, and 27d as shown in FIGS. In this case, the control device 50 stops the use- side blowers 20a, 20b, 20c, and 20d and opens the opening of the flow rate adjusting valves 25a, 25b, 25c, and 25d, so that the heat medium is not changed. Heat can be stored inside the pipe 5.

According to the fourth embodiment, in the heat storage mode, the control device 50 uses the heat medium piping to heat or cool the heat medium flowing in the use side heat exchangers 26a, 26b, 26c, and 26d that have not been subjected to heat exchange. 5 has a heat storage means 51a for storing the inside. Furthermore, in the heat storage means 51a, when the use side heat exchangers 26a, 26b, 26c, and 26d are installed in the indoor space 7 where a person is present, the use side heat exchanger 26a in which heat exchange is not performed. , 26b, 26c, and 26d, the hot or cold heat of the heat medium flowing through the heat medium is stored in the heat medium pipe 5. Thereby, heat can be stored not only in the vacant chamber but also in the heat medium pipe 5. For this reason, the amount of heat storage increases, and freezing of the heat medium can be further suppressed. Further, the use side heat exchangers 26a, 26b, 26c, and 26d are further provided with use side fans 20a, 20b, 20c, and 20d, and the heat storage means 51a includes the use side heat exchangers 26a, 26a, You may comprise so that the use side air blower 20a, 20b, 20c, 20d may be stopped, and the inside of the heat medium piping 5 may store the heat or cold which the heat medium which flows into 26b, 26c, 26d has. In this case, heat can be stored inside the heat medium pipe 5 without changing the room temperature. Further, bypass circuits 27a, 27b, 27c, 27d that connect the inlet side and the outlet side of the use side heat exchangers 26a, 26b, 26c, 26d and bypass the heat medium carried by the pumps 21a, 21b, and the pump 21a. , 21b is further provided with flow rate adjustment valves 25a, 25b, 25c, 25d for switching so that the heat medium carried by 21b flows to the use side heat exchangers 26a, 26b, 26c, 26d or the bypass circuits 27a, 27b, 27c, 27d. In the heat medium circuit having the use side heat exchangers 26a, 26b, 26c, and 26d in which heat exchange is not performed, the heat storage means 51a is a flow rate adjusting valve so that the heat medium flows to the bypass circuits 27a, 27b, 27c, and 27d. 25a, 25b, 25c, and 25d are switched. Thereby, it is possible to store heat in the heat medium pipe 5 connected to the use side heat exchangers 26a, 26b, 26c, and 26d that have not been subjected to heat exchange.

Embodiment 5 FIG.
The fifth embodiment is different from the first embodiment in that the heat storage amount is calculated. In the fifth embodiment, the same parts as those in the first embodiment are denoted by the same reference numerals, and the description thereof will be omitted. The description will focus on differences from the first embodiment.

The heat storage means 51a calculates the amount of heat stored based on the temperature of the heat medium. The heat storage amount of the heat medium can be calculated from the product of the mass, density, constant pressure specific heat and temperature of the heat medium, as shown in equation (1). Since the characteristics of the heat medium and the characteristics of the heat medium pipe 5 are known when the air conditioning system 100 is constructed, the mass, density, and constant pressure specific heat of the heat medium are known.

Here, the amount of heat stored in the vacant space can be simply estimated based on the temperature increase rate of the heat medium. For example, the control device 50 sets the use- side fans 20a, 20b, 20c, and 20d in a state where the stop valves 24a, 24b, 24c, and 24d are fully closed or the flow rate adjustment valves 25a, 25b, 25c, and 25d are fully closed. Make it work. As a result, the temperature of the heat medium increases without changing the flow rate of the heat medium, and the difference between the heat medium and the room temperature is reduced. When the time until the temperature of the heat medium changes to the room temperature is short, it can be estimated that the heat storage amount of the vacant room is large. Therefore, the heat storage amount of the vacant room can be estimated based on the correspondence between the temperature of the heat medium and time.

In the fifth embodiment, a heat medium temperature sensor for detecting the temperature of the heat medium is further provided, and the control device 50 has a function of obtaining the amount of heat stored based on the temperature of the heat medium detected by the heat medium temperature sensor. Have. By calculating the heat storage amount, it is possible to grasp in advance the amount of heat that can be used to prevent freezing. For this reason, the convenience at the time of utilizing cold heat or warm heat improves.

Note that the control device 50 operates the compressor 10 with the stop valves 24a, 24b, 24c, and 24d fully opened and the flow rate adjusting valves 25a, 25b, 25c, and 25d fully opened to control the flow rate of the heat medium. You may measure. In this case, the control device 50 can estimate the heat storage amount of the vacant room based on the flow rate of the heat medium and the difference between the room temperature and the target temperature.

Embodiment 6 FIG.
FIG. 17 is a flowchart showing an energy saving control operation of the air conditioning system 100 according to Embodiment 6 of the present invention. The sixth embodiment is different from the first embodiment in that the control is performed when the air conditioning capability is suppressed. In the sixth embodiment, the same parts as those in the first embodiment are denoted by the same reference numerals, and the description thereof is omitted. The description will focus on differences from the first embodiment.

If the rotation speed of the compressor 10 is reduced in order to suppress the air conditioning capability, the power factor of the motor serving as the power of the compressor 10 is deteriorated. For this reason, the energy consumption for the cooling capacity or the heating capacity increases when the rotational speed of the compressor 10 is low than when it is high. In the sixth embodiment, heat storage and use of heat storage are performed while avoiding a low speed of the compressor 10.

When the difference between the temperature detected by the heat medium temperature sensor and the temperature detected by the room temperature sensor 39 is equal to or less than the temperature difference threshold value, the heat storage unit 51a stores cold heat or heat in the heat medium pipe 5.

17, step ST31 to step ST40 and step ST71 to step ST73 are the same as step ST31 to step ST40 and step ST71 to step ST73 shown in FIG. As shown in FIG. 17, when the use side units 2a, 2b, 2c, and 2d are operating in step ST71, does the control device 50 need an air conditioning capability that makes the rotation speed of the compressor 10 low? Is determined (step ST81). That is, it is determined whether the difference between the temperature on the outlet side of the use side heat exchangers 26a, 26b, 26c, and 26d and the room temperature is equal to or less than the temperature difference threshold value. If the difference is equal to or smaller than the temperature difference threshold value, it is determined whether the temperature of the heat medium is the target temperature (step ST82).

When the temperature of the heat medium is the target temperature, the compressor 10 is stopped, the stored heat is used, and the operation is continued (step ST83). On the other hand, when the temperature of the heat medium is not the target temperature, the rotation speed of the compressor 10 is maintained (step ST84). Then, the heat medium flow control means 51c restricts the opening degree of the flow rate adjustment valves 25a, 25b, 25c, 25d connected to the use side units 2a, 2b, 2c, 2d (n) (step ST85). For example, the flow control valves 25a, 25b, 25c, and 25d are set to intermediate openings, and heat is applied to any of the use side heat exchangers 26a, 26b, 26c, and 26d and the bypass circuits 27a, 27b, 27c, and 27d. The medium is adjusted to flow. Thereby, heat is stored inside the heat medium pipe 5 while suppressing the air conditioning capability (step ST86).

According to the sixth embodiment, the heat medium temperature sensor that detects the temperature of the heat medium and the indoor temperature sensor 39 that detects the temperature of the air-conditioning target space are further provided, and the heat storage means 51a is controlled by the heat medium temperature sensor. When the difference between the detected temperature and the temperature detected by the room temperature sensor 39 is equal to or lower than the temperature difference threshold value, the hot or cold heat of the heat medium is stored. Thereby, air-conditioning capability can be suppressed, without making it the rotation speed from which the efficiency of the compressor 10 deteriorates. That is, heat storage can be performed while suppressing the air conditioning capability. Therefore, energy efficiency is high.

Embodiment 7 FIG.
FIG. 18 is a flowchart showing the operation of the computer room protection control of the air conditioning system 100 according to Embodiment 7 of the present invention. The seventh embodiment is different from the first embodiment in that the control is to protect the computer room. In the seventh embodiment, the same parts as those in the first embodiment are denoted by the same reference numerals, and the description thereof will be omitted. The description will focus on differences from the first embodiment.

Embodiment 7 exemplifies an air conditioning system 100 installed in a building 9 or the like including a space such as a computer room where it is necessary to avoid a temperature rise. The temperature increase rate of the indoor space 7 in the computer room is higher than the temperature increase rate of the indoor space 7 other than the computer room. Since the computer or the like is generating heat, the computer room is constantly cooled in order to prevent the computer or the like from being damaged due to a high temperature. In the seventh embodiment, during abnormal operation such as failure of the heat source unit 1, the temperature rise of the computer room that is always cooled using the cold stored in the heat medium pipe 5 or in the vacant room in advance. Suppress. That is, when the computer room cannot be cooled, the temperature rise of the computer room is suppressed by using the cold heat of the indoor space 7 other than the computer room that tends to be lower in temperature than the indoor space 7 of the computer room. If there is cold energy stored, the computer room can be further cooled.

The heat storage means 51a determines whether or not the computer room has been registered in the space information 55b, and determines whether or not the heat source unit 1 has all failed. Here, the state that all the heat source side units 1 are out of order indicates that the communication with the heat source side unit 1 becomes impossible, or that the heat source side unit 1 performs an operation different from the user's intention. This is not during normal operation. When the computer room has been registered and the heat source side unit 1 has all failed, the control device 50 stops the use side units 2a, 2b, 2c, and 2d installed in the indoor space 7 other than the computer room. And the control apparatus 50 sets indoor space 7 other than a computer room to an empty room, and operates the utilization side air blowers 20a, 20b, 20c, and 20d installed in the computer room. Thereby, the cold heat stored in the housing is sent to the computer room, and the computer room can be cooled.

As shown in FIG. 18, the control device 50 determines whether or not the computer room has been registered in the space information 55b, and determines whether or not all the heat source side units 1 have failed (step ST91). When the computer room has been registered and all the heat source side units 1 have failed, the control device 50 stops the use side units 2a, 2b, 2c, 2d installed in the indoor space 7 other than the computer room (step) ST92). And the control apparatus 50 sets indoor space 7 other than a computer room to an empty room (step ST93), and operates the utilization side air blowers 20a, 20b, 20c, and 20d installed in the computer room (step ST94).

Thereby, the control device 50 can send the cold energy stored in the housing to the computer room (step ST95) and cool the computer room. Specifically, when the cold energy stored in the housing is used in step ST95, the use side unit 2a installed in the indoor space 7 other than the computer room is processed by the processing in steps ST35 to ST38 shown in FIG. Cold heat is stored inside the heat medium pipe 5 in 2b, 2c, and 2d. And use side unit 2a, 2b, 2c, 2d installed in the computer room can suppress a temperature rise by the cold stored in the inside of the heat-medium piping 5. FIG.

According to the seventh embodiment, when the refrigerant circuit abnormally operates, the control device 50 uses the heat stored in the heat storage mode in the use- side heat exchangers 26a and 26b installed in the computer room that is constantly cooled. , 26c, 26d. In this way, when the heat source side unit 1 operates abnormally, the indoor space 7 other than the computer room is set as an empty room, and heat storage is performed, so that the temperature rise of the computer room can be suppressed.

1 heat source side unit, 2, 2a, 2b, 2c, 2d usage side unit, 3 relay unit, 3a parent relay unit, 3b child relay unit, 4 refrigerant piping, 5 heat medium piping, 6 outdoor space, 7 indoor space, 8 Non-air-conditioned space, 9 building, 10 compressor, 11 flow path switching device, 12 heat source side heat exchanger, 13 heat source side flow path adjustment unit, 13b first check valve, 13c second check valve, 13a second 3 check valve, 13d fourth check valve, 14 gas-liquid separator, 15, 15a, 15b intermediate heat exchanger, 16a, 16b, 16c, 16d child expansion part, 16, 16e expansion part, 17 accumulator, 18 Relay unit, 20, 20a, 20b, 20c, 20d Use side blower, 21, 21a, 21b pump, 22, 22a, 22b, 22c, 22d Path switching valve, 23, 23a, 23b, 23c, 23d flow path switching valve, 24, 24a, 24b, 24c, 24d stop valve, 25, 25a, 25b, 25c, 25d flow control valve, 26, 26a, 26b, 26c , 26d use side heat exchanger, 27, 27a, 27b, 27c, 27d bypass circuit, 31a, 31b first heat medium temperature sensor, 32a, 32b second heat medium temperature sensor, 33a, 33b, 33c, 33d second 3 heat medium temperature sensor, 34a, 34b, 34c, 34d, 4th heat medium temperature sensor, 35 5th temperature sensor, 36 pressure sensor, 37 6th temperature sensor, 38 7th temperature sensor, 39 indoor temperature Sensor, 50 control device, 50a heat source side control device, 50b relay side control device, 51 control judgment unit, 51a heat storage means 51b Freezing suppression means, 51c Heat medium flow control means, 52 input section, 53 output section, 54 communication section, 55 storage means, 55a heat medium flow control information, 55b space information, 55c history information, 55d permission information, 100 air conditioning system .

Claims (17)

1. A refrigerant circuit in which a compressor, a heat source side heat exchanger, an expansion unit, and an intermediate heat exchanger for exchanging heat between the refrigerant and the heat medium are connected by a refrigerant pipe, and the refrigerant flows;
   A heat medium circuit in which the pump, the intermediate heat exchanger and the use side heat exchanger are connected by a heat medium pipe, and the heat medium flows;
   When the compressor is operating, the heat storage mode for storing the heat or cold of the heat medium using the use side heat exchanger or the heat medium pipe, and the heat or cold stored in the heat storage mode are used. A control device having a use mode to
   Air conditioning system equipped with.
2. The control device includes:
   2. The air conditioning system according to claim 1, further comprising: a heat storage unit that stores, in the vacant room, hot or cold heat of a heat medium flowing in the use side heat exchanger installed in the empty room where no person is present in the heat storage mode.
3. It further includes an indoor temperature sensor that detects the temperature of the air conditioning target space,
   The control device includes:
   Storage means for storing a history of changes in temperature detected by the indoor temperature sensor;
   The air conditioning system according to claim 2, wherein the heat storage unit has a function of determining whether the air conditioning target space is an empty room based on a history stored in the storage unit.
4. The control device includes:
   Storage means for storing a history of operation of the refrigerant circuit and the heat medium circuit;
   The air conditioning system according to claim 2 or 3, wherein the heat storage unit has a function of determining whether the air-conditioning target space is an empty room based on a history stored in the storage unit.
5. The control device includes:
   5. The air conditioning system according to claim 3, wherein the air conditioning system has a function of determining whether the air-conditioning target space is vacant for each time period based on the history stored in the storage unit.
6. The control device includes:
   The heat storage mode further includes heat storage means for storing the heat or cold of the heat medium flowing in the use side heat exchanger that has not been heat-exchanged inside the heat medium pipe. The air conditioning system described in.
7. The heat storage means is
   When the use side heat exchanger is installed in an indoor space where a person is present, the heat medium having the heat medium flowing in the use side heat exchanger that has not been subjected to heat exchange has the heat medium. The air conditioning system according to claim 6, wherein the air conditioning system is stored in a pipe.
8. A bypass circuit that connects an inlet side and an outlet side of the use side heat exchanger, and bypasses the heat medium conveyed by the pump;
   A flow rate adjusting valve that switches so that the heat medium conveyed by the pump flows to the use side heat exchanger or the bypass circuit, and
   The heat storage means is
   The air conditioning system according to claim 6 or 7, wherein in the heat medium circuit having the use side heat exchanger that has not been subjected to heat exchange, the flow rate adjustment valve is switched so that the heat medium flows into the bypass circuit.
9. A use side blower for sending air to the use side heat exchanger;
   The heat storage means is
   9. The hot or cold heat of a heat medium flowing through the use side heat exchanger that has not been subjected to heat exchange is stored in the heat medium pipe by stopping the use side blower. The air conditioning system according to item 1.
10. A heat medium temperature sensor for detecting a temperature of the heat medium;
    The control device includes:
    In the use mode, when the temperature of the heat medium detected by the heat medium temperature sensor is equal to or lower than the temperature threshold, the freezing suppression that suppresses freezing of the heat medium by flowing the heat stored in the heat storage mode to the heat medium. The air conditioning system according to any one of claims 1 to 9, further comprising means.
11. A heat medium temperature sensor for detecting a temperature of the heat medium;
    The control device includes:
    The air conditioning system according to any one of claims 1 to 10, wherein the air conditioning system has a function of obtaining an amount of heat stored based on a temperature of the heat medium detected by the heat medium temperature sensor.
12. A heat medium temperature sensor for detecting the temperature of the heat medium;
    An indoor temperature sensor for detecting the temperature of the air-conditioned space,
    The heat storage means is
    The hot or cold heat of the heat medium is stored when the difference between the temperature detected by the heat medium temperature sensor and the temperature detected by the indoor temperature sensor is equal to or less than a temperature difference threshold value. The air conditioning system described in.
13. The control device includes:
    The function of supplying cold energy stored in the heat storage mode to the use side heat exchanger installed in a computer room that is constantly cooled when the refrigerant circuit operates abnormally. The air conditioning system according to item 1.
14. A heat source side unit having the compressor and the heat source side heat exchanger;
    A use side unit each having a plurality of use side heat exchangers;
    A relay unit that includes the intermediate heat exchanger, the expansion unit, and the pump, and distributes the heat or cold generated by the heat source side unit to the user side unit;
    The air conditioning system according to any one of claims 1 to 13, wherein a plurality of the use side units are operated in a mixed manner.
15. A use side unit to which hot or cold generated by the heat source side unit is supplied via a relay unit,
    A use side heat exchanger;
    A bypass circuit that connects an inlet side and an outlet side of the use side heat exchanger, and bypasses a heat medium conveyed by a pump provided in the relay unit;
    Use side unit with.
16. When the compressor is operating, a heat storage mode for storing the heat or cold of the heat medium using the use-side heat exchanger or the heat medium piping, and a use mode for using the heat or cold stored in the heat storage mode When,
    Control device.
17. When the compressor is operating, the step of storing the heat or cold of the heat medium using the use side heat exchanger or the heat medium pipe;
    Using the stored hot or cold energy;
    Control method.

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