JPH11211259A - Heat storage heat pump air conditioner - Google Patents

Abstract

(57) [Problem] To provide a regenerative heat pump air conditioner that eliminates imbalance during heat storage and performs stable operation. A refrigerant discharged from a compressor is supplied to a four-way valve, an outdoor heat exchanger, a pressure reducing mechanism, and a heat storage heat exchanger.
0, a four-way valve 4, and a compressor 3 to circulate in order to store heat in the heat storage tank 9 and a heat storage material stored in the heat storage tank 9 to the indoor unit (20). In the regenerative heat pump air conditioner comprising the heat storage material circulating circuit 2, the heat storage heat exchanger 10
The auxiliary heat exchanger 11 was provided in parallel with the above.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a regenerative heat pump air conditioner.

[0002]

2. Description of the Related Art FIG. 4 is a circuit diagram of a conventional refrigeration cycle. This type of refrigeration cycle is disclosed in, for example,
No. 50779 discloses this. This conventional refrigeration cycle includes a cooling / heating unit 33 using a solar battery or a commercial power supply as a power source, and a heat storage tank 35, and a heat storage medium is directly circulated by a pump 36 to a fan coil unit 37 which is an indoor unit.

In this circuit, for example, using a commercial power supply,
When the cooling operation and the heat storage operation for producing ice and the like are performed at night at the same time, it is necessary to perform air conditioning while lowering the temperature of the heat storage material for heat storage. However, the heat storage tank 3 after air conditioning
Since the temperature of the water or the like returning to 5 becomes high, a temperature distribution occurs in the heat storage tank 35, and it is difficult to form ice uniformly.

When air conditioning is performed while preserving a heat storage material such as ice formed on the surface of the heat storage heat converter 34 after the completion of heat storage, such as in the morning of summer, heat resistance increases due to the heat storage material, and the efficiency deteriorates. . Further, since the return water temperature becomes high after the air conditioning, the heat storage material in the heat storage tank 35 has a temperature distribution, and thus it is difficult to keep uniform ice. In addition, when the air conditioner has not been stored, for example, at the time of starting air conditioning, the heat storage tank 35
It is necessary to change the temperature of the entire heat storage material inside, and it takes time to start up.

Further, hot water is produced using solar energy for hot water supply. However, when the temperature of the hot water is greatly affected by the weather, an auxiliary heat source 27 for hot water supply and a solar heat source are provided in addition to the refrigerant circuit and the heat storage material circuit. The heat collector 21 and the like are required, and the equipment cost increases.

[0006]

The above-described conventional refrigeration cycle has the following problems. (1) If the latent heat storage operation using ice or the like at night and the air-conditioning operation are performed simultaneously, the temperature distribution returns to the raised heat storage tank after the air conditioning, causing a temperature distribution in the tank and uniform thickness of ice and the like. But grow unbalanced. For this reason, during the air conditioning operation using heat storage, a bypass circuit of the heat storage material is generated in the heat storage tank, and the temperature of the outlet from the heat storage tank becomes high even though the heat storage material remains, so that air conditioning cannot be performed. Occurs. (2) In order to secure the heat storage amount corresponding to the load, a heat storage tank capacity of a certain amount or more is required. As a result, in normal air-conditioning operation, it is necessary to change the temperature of the entire heat storage material in the system, including in the heat storage tank. Further, the latent heat storage material such as ice manufactured at night must be kept until about 1:00 pm, which is the peak power time zone. However, if the air-conditioning operation is performed in the morning and the flow of the heat storage material is formed in the heat storage tank, part or all of the latent heat storage material such as ice melts or becomes unbalanced, and the air-conditioning operation using the heat storage is performed. Sometimes a bypass circuit for the heat storage material is created in the heat storage tank. (3) At night, it is necessary to simultaneously perform the heat storage operation and the air conditioning operation. For example, when using ice as a heat storage material,
The evaporation temperature of the heat storage heat exchanger for producing ice must be 0 ° C. or less. However, the evaporating temperature for air conditioning needs to be 0 ° C. or higher in order to avoid freezing, and different evaporating temperatures are required in the same refrigerant circuit. (4) At the time of heat storage, the heat storage heat exchanger in the heat storage tank was used. However, at the time of sensible heat storage such as producing high-temperature water, the heat exchange rate is low because the heat storage tank has natural convection. (5) Since solar heat is used, performance is greatly affected by weather and seasons, and uniform hot water temperature and quantity cannot be obtained.
In addition, since a solar heat collector is required, there is a problem that the price increases. An object of the present invention is to provide a heat storage heat pump air conditioner that eliminates imbalance during heat storage and performs stable operation.

[0007]

Means for Solving the Problems To solve the above problems and achieve the object, a heat storage type heat pump air conditioner of the present invention is configured as follows. (1) In the regenerative heat pump air conditioner of the present invention, the refrigerant discharged from the compressor is sequentially circulated through the four-way valve, the outdoor heat exchanger, the pressure reducing mechanism, the heat storage heat exchanger, the four-way valve, and the compressor. In a heat storage type heat pump air conditioner including a refrigerant circulation circuit that stores heat in a heat storage tank and a heat storage material circulation circuit that circulates the heat storage material stored in the heat storage tank to an indoor unit,
An auxiliary heat exchanger was provided in the heat storage material circulation circuit in parallel with the heat storage heat exchanger. (2) A regenerative heat pump air conditioner according to the present invention is the air conditioner according to the above (1), wherein a first bypass circuit for bypassing the heat storage tank is provided in the heat storage material circulating circuit. The path can be a circulation pump, the indoor unit, the auxiliary heat exchanger, the switching valve, the first bypass circuit, and the circulation pump, bypassing the heat storage tank. (3) The regenerative heat pump air conditioner of the present invention is the air conditioner according to the above (1) or (2), and a decompression mechanism is provided on the cooling heat outlet side of the auxiliary heat exchanger. (4) A regenerative heat pump air conditioner of the present invention is the air conditioner according to any one of (1) to (3) above, and a second air conditioner that bypasses the indoor unit in the heat storage material circulation path. A bypass circuit is provided, and the heat storage material path is connected to the heat storage tank, the circulation pump, the switching valve, the second bypass circuit,
The heat storage tank can be used. (5) The regenerative heat pump air conditioner of the present invention is the air conditioner according to any one of the above (1) to (4), and transfers the refrigerant discharged from the compressor between the four-way valves. A refrigerant circuit was provided which branched off from the discharge pipe, entered into a hot water supply heat exchanger for heat exchange with water in a hot water tank via an operation valve, and returned to the heat exchanger outlet side pipe of the outdoor unit via the operation valve.

[0008]

(First Embodiment) FIG. 1 is a circuit diagram showing a refrigeration cycle of a regenerative heat pump air conditioner according to a first embodiment of the present invention. Refrigerant circuit 1
The upper outdoor unit side A includes a compressor 3, a four-way valve 4, an outdoor heat exchanger 5, an accumulator 12, an operation valve 14, a check valve 6a,
The stop mechanism 7a is provided. The heat storage tank side B on the refrigerant circuit 1 includes a heat storage tank 9, a heat storage heat exchanger 10, two-way valves 8a, 8
b, 8c, throttle mechanisms 7b, 7c, 7d, check valves 6b, 6
c, 6d, and the auxiliary heat exchanger 11. Further, a pump 13a, a three-way valve 15a,
15b, a first heat storage material bypass circuit 16a, and a second heat storage material bypass circuit 16b are provided, and the indoor heat exchanger 20 of the air conditioning indoor unit is connected.

The operation of the refrigerant circuit 1 and the heat storage material circulation circuit 2 is as follows. When air conditioning is performed using the heat storage material stored in the heat storage tank 9, the outdoor unit A does not operate, and heat is exchanged and air-conditioned in the heat storage material circulation circuit 2. The heat storage material in the heat storage tank 9 is sucked and pressurized by the pump 13a, discharged, and proceeds to the indoor heat exchanger 20. In the indoor heat exchanger 20, during cooling, a heat storage material such as cold water flows, so that heat is absorbed and the temperature of the heat storage material rises. At the time of heating, the heat storage material such as hot water flows to dissipate heat and lower the temperature of the heat storage material. The heat storage material whose temperature has changed in the indoor unit is supplied to the auxiliary heat exchanger 11.
And returns to the heat storage tank 9.

When performing air conditioning using a heat storage material,
Since the outdoor unit is not used, heat exchange in the auxiliary heat exchanger 11 is not performed. Since heat is exchanged in the indoor unit, the temperature of the heat storage material at the time of cooling becomes higher at the return port than at the exit of the heat storage tank 9, and at the time of heating, the temperature at the return port becomes lower than the outlet of the heat storage tank 9. The amount of heat stored in the tank 9 gradually decreases. When performing air conditioning while preserving the heat storage material stored in the heat storage tank 9 or when performing air conditioning when heat is not stored, the outdoor unit needs to be operated. The operation of the refrigerant circuit 1 at this time is as follows.

The refrigerant gas which has become high pressure and high temperature in the compressor 3 is
It enters the outdoor heat exchanger 5 through the four-way valve 4 and condenses and liquefies. After that, the gas passes through the check valve 6a, the operating valve 14, and the two-way valve 8a, and expands to a low pressure by the throttle mechanism 7d. The auxiliary heat exchanger 11 exchanges heat with the heat storage material, evaporates, and forms a low-pressure gas. Become. After that, it enters the accumulator 12 through the two-way valve 8d, the operation valve 14, and the four-way valve 4, and returns to the compressor 3. The operation of the heat storage material circulation circuit 2 at this time is as follows.

In the auxiliary heat exchanger 11, the heat storage material that has become low in temperature by exchanging heat with the refrigerant passes through the three-way valve 15a, enters the first heat storage material bypass circuit 16a, and proceeds to the pump 13a to the indoor heat exchanger 20. Then, after the temperature rises, the process returns to the auxiliary heat exchanger 11. By configuring such a circuit, stable air conditioning can be performed regardless of the presence or absence of the heat storage material stored in the heat storage tank 9 and the capacity of the heat storage tank 9. When cooling and heat storage (production of ice or the like) are performed simultaneously at night, in the refrigerant circuit 1, the refrigerant condenses and liquefies in the outdoor heat exchanger 5, passes through the check valve 6 a, and passes through the operation valve 14. , The auxiliary heat exchanger 11 and the heat storage heat exchanger 10. In the heat storage heat exchanger 10, ice and the like store latent heat, and in the auxiliary heat exchanger 11, the refrigerant evaporates and exchanges heat for air conditioning.

Here, the heat storage heat exchanger 1 in which ice or the like is generated
The required evaporating temperature differs between 0 and the auxiliary heat exchanger 11 for air conditioning. The heat storage heat exchanger 10 requires 0 ° C. or lower, and the auxiliary heat exchanger 11 requires 0 ° C. or higher to prevent icing. For this reason, a throttle mechanism 7c was provided at the outlet of the auxiliary heat exchanger 11 to re-expand it, so that the outlet pressure of the heat storage heat exchanger 10 was matched.

FIG. 2 is a Mollier diagram of the refrigeration cycle. In the heat storage material circulating circuit 2, the heat storage material includes the auxiliary heat exchanger 11, the first heat storage tank bypass circuit 16 a, and the pump 13.
a) Since the heat storage material proceeds to the indoor heat exchanger 20 and returns to the auxiliary heat exchanger 11, the heat storage material whose temperature has increased after air conditioning does not return to the heat storage tank 9, and a large temperature distribution does not occur in the heat storage tank 9.

At the time of sensible heat storage for producing high-temperature water, the refrigerant circuit 1 operates as follows. The high-temperature and high-pressure refrigerant gas that has exited the compressor 3 passes through the four-way valve 4 to the operating valve 14, where it is condensed and liquefied in one or both of the heat storage heat exchanger 10 and the auxiliary heat exchanger 11. The heat exchanger used here is selected according to the amount of heat exchange, the amount of refrigerant sealed in the heat exchanger, and the like.

The liquefied refrigerant passes through the check valves 6b and 6d and expands to a low pressure through the operation valve 14 by the throttle mechanism 7a. The refrigerant is evaporated and gasified by the outdoor heat exchanger 5, and the four-way valve 4 and the accumulator 12 are discharged. After that, the process returns to the compressor 3. The heat storage material circulating circuit 2 is caused to flow in order to improve heat exchange in the heat storage heat exchanger 10 and the auxiliary heat exchanger 11, and is as follows.

The heat storage material exiting the heat storage tank 9 enters the pump 13a, and passes through the three-way valve 15b to the second heat storage material bypass circuit 16a.
b, and then into the heat storage tank 9 through the auxiliary heat exchanger 11 and the three-way valve 15a. That is, since the heat storage material does not flow to the indoor unit 20, heat loss is small, and efficient heat storage can be performed.

(Second Embodiment) FIG. 3 is a circuit diagram of a refrigeration cycle of a regenerative heat pump air conditioner according to a second embodiment of the present invention. 3, the same parts as those in FIG. 1 are denoted by the same reference numerals. The second embodiment is a system in which hot water can be supplied in addition to the air-conditioning heat storage system shown in the first embodiment. Hot water supply side C
Is a hot water supply tank 19, a pump 13b, a hot water supply heat exchanger 17,
It is composed of a hot water supply water circuit 18 and an operation valve 14.

The operation of the refrigerant circuit 1 is as follows. The high-temperature, high-pressure refrigerant gas discharged from the compressor 3 is supplied to the two-way valve 8.
f, the hot water supply heat exchanger 17 on the hot water supply side C passing through the operation valve 14
To condense and liquefy, and radiate heat to the hot water supply water circuit 18 to raise the water temperature. After that, it is expanded by the throttle mechanism 7a through the operation valve 14 and the check valve 6e, becomes low pressure, enters the outdoor heat exchanger 5, evaporates, and returns to the compressor 3 through the four-way valve 4 and the accumulator 12.

When the refrigerant is stored in the heat storage heat exchanger 10 or the auxiliary heat exchanger 11, the two-way valve 8g can be opened to return the stored refrigerant to the outdoor unit A where the pressure becomes low. . In the hot water supply water circuit 18, the liquefied refrigerant gas exits the hot water supply heat exchanger 17 and then enters the hot water supply tank 19 where the pump 1
Returning to the hot water supply heat exchanger 17 via 3b, the water temperature is gradually increased. The present invention is not limited to only the above embodiments, and can be implemented with appropriate modifications without departing from the scope of the invention.

[0021]

(1) According to the heat storage heat pump air conditioner of the present invention, the temperature of the heat storage material whose temperature has increased due to the air conditioning load is provided to the circulation path for circulating the heat storage material stored in the heat storage tank to the indoor unit. An auxiliary heat exchanger has been installed to reduce the That is, an auxiliary heat exchanger is arranged in parallel with the heat storage heat exchanger in the circulation path of the heat storage material, and the heat exchange between the heat storage material and the refrigerant is performed so that the return water temperature after the air conditioning approaches the inlet side temperature of the air conditioner. be able to. Since the temperature of the water returned to the heat storage tank is close to the inlet temperature, the temperature distribution of the heat storage material in the heat storage tank does not become unbalanced, and the heat storage material such as ice can be grown uniformly.

Even if the simultaneous operation of the heat storage operation for producing ice and the like and the cooling air conditioning operation at night is performed, the increased water temperature after air conditioning can be reduced by using the auxiliary heat exchanger. Etc. can be grown uniformly. Therefore, at the time of performing the air conditioning using the heat storage material, the heat storage material such as ice can be uniformly melted, so that a stable temperature of the heat storage material for air conditioning can be taken out without generating a bypass circuit. (2) According to the regenerative heat pump air conditioner of the present invention, switching to the first bypass circuit for bypassing the heat storage tank is performed on the heat storage material circulation path including the heat storage tank, the circulation pump, the air conditioning indoor unit, and the heat storage tank. A valve is provided to enable a circulation path of the bypass circuit, the circulation pump, the air conditioning indoor unit, and the bypass circuit. That is, by providing the first bypass circuit that bypasses the heat storage tank as a circulation path of the heat storage material and using the above-described exchanger, the air conditioning operation can be performed while maintaining the temperature of the heat storage material in the heat storage tank. become. In addition, the start-up time of the air-conditioning operation can be shortened, and the heat-storage material having already stored heat can be preserved for the air-conditioning load in the morning until the peak power load in the afternoon. (3) According to the regenerative heat pump air conditioner of the present invention, when performing low-temperature heat storage such as ice storage in the refrigerant circuit in which the heat storage heat exchanger and the auxiliary heat exchanger are connected in parallel, the auxiliary heat exchange is performed. By providing a decompression mechanism between the outlet of the heat exchanger and the connection port of the heat storage heat exchanger, it is possible to heat the heat exchangers connected in parallel to different evaporation temperatures, respectively, for air conditioning Without freezing the auxiliary heat exchanger,
It becomes possible to grow a heat storage material such as ice in the heat storage heat exchanger. That is, by providing a decompression mechanism at the outlet of the auxiliary heat exchanger, the evaporating temperature of the auxiliary heat exchanger for air conditioning is set to 0 ° C. or more, and the evaporating temperature of the heat storage heat exchanger is set to 0 ° C. or less. It is possible to produce different evaporation temperatures. (4) According to the regenerative heat pump air conditioner of the present invention, the second bypass circuit that bypasses the indoor unit is provided in the heat storage material circulation path, so that the heat storage material flows without being sent to the indoor unit during the heat storage operation. It becomes possible. This allows the heat storage material in the heat storage tank to flow during the sensible heat storage operation, thereby improving the heat transfer coefficient during heat storage, and minimizing the heat dissipation loss because it does not pass through indoor units. The use of an auxiliary heat exchanger is also possible. Therefore, the amount of heat exchange during the sensible heat storage operation can be increased, so that the time until the completion of the heat storage can be shortened, and the heat storage operation can be performed efficiently. (5) According to the regenerative heat pump air conditioner of the present invention, a refrigerant circuit for guiding a high-temperature, high-pressure refrigerant gas discharged from a compressor to a hot-water supply heat exchanger is provided and used as a heat source for hot-water supply. When hot water is supplied by an outdoor unit for air conditioning using nighttime electric power, an efficient hot water supply operation can be performed without being affected by the weather or the like. That is, by providing a refrigerant circuit for guiding the high-temperature, high-pressure refrigerant gas discharged from the compressor to the hot water supply heat exchanger, an efficient hot water supply operation using a heat pump can be performed regardless of weather and time.

[Brief description of the drawings]

FIG. 1 is a circuit diagram of a refrigeration cycle of a regenerative heat pump air conditioner according to a first embodiment of the present invention.

FIG. 2 is a Mollier diagram of the refrigeration cycle according to the first embodiment of the present invention.

FIG. 3 is a circuit diagram of a refrigeration cycle of a regenerative heat pump air conditioner according to a second embodiment of the present invention.

FIG. 4 is a circuit diagram of a refrigeration cycle according to a conventional example.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Refrigerant circuit 2 ... Heat storage material circulation circuit 3 ... Compressor 4 ... Four-way valve 5 ... Outdoor heat exchanger 6a-6d ... Check valve 7a-7d ... Throttle mechanism (decompression mechanism) 8a-8d ... Two-way valve 9 ... Heat storage tank 10 Heat storage heat exchanger 11 Auxiliary heat exchanger 12 Accumulators 13a and 13b Pump 14 Operating valves 15a and 15b Three-way valve 16a First heat storage material bypass circuit 16b Second heat storage material bypass circuit DESCRIPTION OF SYMBOLS 17 ... Heat supply heat exchanger 18 ... Hot supply water circuit 19 ... Hot supply tank 20 ... Indoor heat exchanger 21 ... Heat collector 22 ... Heat collecting plate 23 ... Solar cell 24 ... Pump 25 ... First heat storage tank 26 ... Hot water Heater 27 ... Auxiliary heat source 30 ... DC / AC converter 31 ... Commercial power supply 32 ... Changeover switch 33 ... Cooler / heater 34 ... Indoor heat exchanger 35 ... Second heat storage tank 36 ... Pump 37 ... Fan coil unit

 ────────────────────────────────────────────────── ─── Continued on the front page (72) Inventor Masahiko Sasakura 3-1-1, Asahicho, Nishi-Biwajima-cho, Nishi-Kasugai-gun, Aichi Prefecture Mitsubishi Heavy Industries, Ltd. Air Conditioning Works

Claims (5)

[Claims] 1. A refrigerant circulation system in which refrigerant discharged from a compressor is sequentially circulated through a four-way valve, an outdoor heat exchanger, a pressure reducing mechanism, a heat storage heat exchanger, a four-way valve, and a compressor to store heat in a heat storage tank. In a heat storage type heat pump air conditioner comprising a circuit and a heat storage material circulating circuit for circulating the heat storage material stored in the heat storage tank to the indoor unit, the heat storage material circulating circuit includes auxiliary heat in parallel with the heat storage heat exchanger. A regenerative heat pump air conditioner comprising an exchanger. 2. The heat storage material circulating circuit is provided with a first bypass circuit that bypasses the heat storage tank, and a circulating pump, the indoor unit, and the auxiliary heat exchanger that pass through the heat storage material path and bypass the heat storage tank. The regenerative heat pump air conditioner according to claim 1, wherein the regenerative heat pump air conditioner can be a switching valve, the first bypass circuit, and the circulation pump. 3. The regenerative heat pump air conditioner according to claim 1, wherein a pressure reducing mechanism is provided on an outlet side of the auxiliary heat exchanger during cooling. 4. A heat storage material circulation path is provided with a second bypass circuit for bypassing the indoor unit, and the heat storage material path is connected to the heat storage tank, the circulation pump, the switching valve, the second bypass circuit, the heat storage The regenerative heat pump air conditioner according to any one of claims 1 to 3, wherein the air conditioner can be a tank. 5. The refrigerant discharged from the compressor is branched from a discharge pipe between the four-way valves, passed through an operation valve, and put into a hot water supply heat exchanger for heat exchange with water in a hot water tank. The regenerative heat pump air conditioner according to any one of claims 1 to 4, further comprising a refrigerant circuit for returning the refrigerant to a heat exchanger outlet pipe of the outdoor unit via a valve.