JP3404133B2 - Thermal storage type air conditioner - Google Patents

Abstract

PURPOSE:To enhance indoor comfortableness at the time of defrosting in winter and to effectively utilize night power in the refrigerating cycle of a thermal storage type air conditioner having a thermal storage tank. CONSTITUTION:A bypass circuit for connecting a refrigerant-to-refrigerant heat exchanger HEX and a thermal storage tank STR in a secondary side refrigerating cycle are connected in series via a bypass valve BV is installed. An outdoor side heat exchanger 4 is defrosted when a thermal storage material 16 in the tank STR is a predetermined temperature or higher. Accordingly, the valve BV is opened, a primary side refrigerating cycle and a secondary side refrigerating cycle are operated. A defrost controller CN for closing the valve BV and operating only the primary cycle in the case of defrosting the exchanger 4 when the material 16 is lower than a predetermined temperature is installed.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an air conditioner using air as a heat source in the winter defrosting operation of a heat storage type air conditioner having a heat storage / radiation function for utilizing night power and a control function thereof. Regarding

[0002]

2. Description of the Related Art A heat storage type air conditioner has already been variously developed, and for example, a heat storage type as shown in P.358 of Refrigeration Vol. 62, No. 714 (April 1987). There is an air conditioner.

The basic technique will be described with reference to FIG.
As shown in FIG. 1, the air-cooling heat pump 1 has a refrigeration cycle A in which a compressor 2, a four-way valve 3, an outdoor heat exchanger 4, an outdoor expansion valve 5, a Freon-to-brine heat exchanger 6 are sequentially connected in an annular shape.
On the other hand, a freon-to-brine heat exchanger 6, a brine-to-water heat exchanger 7 and a parallel connection circuit of the heat storage tank 8 and a brine pump 9 are sequentially connected in an annular shape to form a brine circulation cycle B. .

On the load side, a brine-to-water heat exchanger 7, a heat storage tank 8, a cold / hot water pump 10 and an indoor unit 12 are sequentially connected in an annular shape to form a cold / hot water circulation cycle C.

In this heat storage type air conditioner, the night operation is switched to the ice making / cooling operation and the heat storage / heating operation by the four-way valve 3 in the refrigeration cycle A.

Particularly, in the winter operation, that is, only in the heat storage / heating operation, the heat storage operation at night is performed in the refrigeration cycle A and the refrigeration cycle B in the direction of the arrow in the solid line in FIG. As a result, a heating cycle is formed, and heat is stored as hot water in the heat storage tank 8 in the brine circulation cycle B via the Freon-to-brine heat exchanger 6 as well. In this case, the brine to water heat exchanger 7 is not used.

In the defrosting operation of the outdoor heat exchanger 4 at night, the refrigeration cycle A and the refrigeration cycle B are
The refrigerant flows in the direction of the broken line arrow in FIG. 4 to form a defrost cycle, and absorbs heat from the hot water in the heat storage tank 8 in the brine circulation cycle B via the Freon-to-brine heat exchanger 6 and the outdoor heat exchanger 4 Defrosting is performed.

On the other hand, during the daytime operation, the cold / hot water circulation cycle C
In FIG. 5, the refrigerant flows in the direction of the solid line arrow in FIG. 5, hot water in the heat storage tank 8 is sent to the indoor unit 12 by the cold / hot water pump 10, and heating operation is performed. At this time, in order to increase the heating capacity,
The refrigeration cycle A and the brine circulation cycle B are operated as a heating cycle, and the brine-to-water heat exchanger 7 and the heat storage tank 8 are configured in parallel in the cold / hot water circulation cycle C to heat water with two heat exchangers. To do.

In the defrosting operation of the outdoor heat exchanger 4 in the daytime, in the refrigerating cycle A, the refrigerating cycle B and the refrigerating cycle C, the refrigerant flows in the direction of the broken line arrow in FIG. 5 to form the defrosting cycle. As in the night operation, the outdoor heat exchanger 4 absorbs heat from the hot water in the heat storage tank 8 in the brine circulation cycle B via the Freon-to-brine heat exchanger 6.
Defrosting is performed.

As described above, by converting the surplus power energy at night into heat to store the heat, and by using the night power at the time of heating start-up in the morning or heating during the daytime in winter, the indoor comfort is improved. Can be improved.

[0011]

However, in the above-mentioned conventional example, since it is necessary to perform heat exchange twice between the heat source side and the load side, efficiency is lowered, and cold / hot water is supplied to the load side. Since it is directly transported, it has a drawback that if a water leakage accident occurs, water damage to OA equipment in an office, which has been recently improved to OA, cannot be avoided.

Therefore, it is an object of the present invention to provide a heat storage type air conditioner having high efficiency, high safety, and high load followability.

[0013]

The technical means of the present invention for solving the above problems is a compressor, a first four-way valve, an outdoor heat exchanger, a first expansion valve, a primary side heat exchange section and a secondary side. The primary side heat exchange section of the refrigerant-to-refrigerant heat exchanger including the side heat exchange section is sequentially connected in an annular shape, and the second expansion valve, the primary side heat exchange section, the secondary side heat exchange section, and the heat storage material are connected. A series connection circuit with the primary side heat exchange section of the heat storage tank is connected in parallel with a series connection circuit with the first expansion valve and the primary side heat exchange section of the refrigerant-refrigerant heat exchanger. A primary side refrigeration cycle, a pump unit including a refrigerant transfer pump and a second four-way valve, a plurality of indoor units, the secondary side heat exchange section of the refrigerant-refrigerant heat exchanger, and a first flow valve. An annular connection of a series connection circuit and a series connection circuit of the secondary heat exchange section and the second flow valve in the heat storage tank connected in parallel A second side refrigeration cycle connected to the second side heat exchange section of the refrigerant-to-refrigerant heat exchanger, the second side heat exchange section being opposite to the first flow valve side of the secondary side heat exchange section, and the second side heat exchange section being in the heat storage tank. A bypass circuit is provided for connecting the two flow rate valves via a bypass valve.

Further, in the defrosting operation of the outdoor heat exchanger when the heat storage material in the heat storage tank is at a predetermined temperature or higher, the bypass valve is opened to operate the primary side refrigeration cycle and the secondary side refrigeration cycle, In addition, in the defrosting operation of the outdoor heat exchanger when the heat storage material is below a predetermined temperature, a defrosting control device that operates only the primary side refrigeration cycle with the bypass valve closed is installed.

[0015]

The function of this technical means is as follows.

First, night driving in winter will be described.
In the primary side refrigeration cycle that communicates with the compressor, the first four-way valve, the outdoor heat exchanger, the second expansion valve, and the primary side heat exchange section in the heat storage tank of the heat storage type air conditioner, during nighttime operation In a state where the refrigerant-refrigerant heat exchanger is not used, heat storage operation is performed in which water, which is a heat storage material, is turned into hot water through the primary side heat exchange section in the heat storage tank by controlling the second expansion valve. At this time, the bypass valve is closed.

When a frosting phenomenon occurs in the outdoor heat exchanger in the heat storage operation at low outside air temperature, the reverse cycle operation is performed in the primary side refrigeration cycle to perform the night defrosting operation. That is, in the primary side refrigeration cycle, the primary side heat exchange section in the heat storage tank is an evaporator and the outdoor side heat exchanger is a condenser to constitute a refrigeration cycle, which absorbs heat from hot water to remove the outdoor side heat exchanger. Do frost. At this time as well, the bypass valve is closed.

Next, the daytime operation in winter will be described.
During daytime heating operation, there are 2 types of pump unit, indoor unit and heat storage tank.
In the secondary side refrigeration cycle including the secondary side heat exchanger and the secondary side heat exchanger of the refrigerant-refrigerant heat exchanger, the heat quantity in the heat storage tank stored as hot water at night is used as the secondary side heat exchanger of the heat storage tank. It is conveyed to the indoor unit via the and heats the room.

At this time, in order to enhance the heating capacity, the primary side heat exchanger of the refrigerant-refrigerant heat exchanger is operated as a condenser in the primary-side refrigeration cycle, and the refrigerant-refrigerant heat exchanger and the heat storage tank are combined. In parallel, the refrigerant in the secondary side refrigeration cycle is heated.
At this time as well, the bypass valve is closed.

Further, even when the outdoor side heat exchanger has a frosting phenomenon even during the heating operation at the low outside air temperature, the reverse cycle operation is performed in the primary side refrigeration cycle to perform the daytime defrosting operation.

That is, in the primary side refrigerating cycle, the refrigerating cycle is constituted by using the primary side heat exchange section in the heat storage tank as the evaporator and the outdoor side heat exchanger as the condenser, as in the night defrosting operation. However, in the secondary refrigeration cycle, the bypass valve is opened, the heat storage tank flow valve is fully closed, and the secondary heat exchanger of the heat storage tank and the secondary heat exchanger of the refrigerant-refrigerant heat exchanger are connected in series. Continue heating operation.

That is, the amount of heat as hot water in the heat storage tank is
The heat is exchanged with the refrigerant through the secondary heat exchanger of the heat storage tank, and then the secondary heat exchanger of the refrigerant-refrigerant heat exchanger is used to defrost the frost adhering to the outdoor heat exchanger. Is absorbed by.

Therefore, although the amount of heat transferred to the indoor unit is reduced and the heating capacity is somewhat reduced, the defrosting operation does not absorb heat from the indoor air and the comfort during heating is not impaired.

[0024]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the accompanying drawings. The same components as those of the prior art will be designated by the same reference numerals and detailed description thereof will be omitted.

FIG. 1 is a refrigeration cycle diagram of the heat storage type air conditioner of one embodiment of the present invention during winter night operation, and FIG. 2 is the heat storage type air conditioner of one embodiment of the present invention during winter daytime operation. It is a refrigerating cycle figure of.

The heat storage type air conditioner is an air-cooled heat pump 1.
, Heat storage tank STR, pump unit PU, and indoor unit 1
2 and.

The air-cooled heat pump 1 includes a compressor 2, a first four-way valve 3a, an outdoor heat exchanger 4, a first expansion valve 5a, a second expansion valve 5b, a primary side heat exchange section 14a and a secondary side heat exchange. Part 14
b to the refrigerant-to-refrigerant heat exchanger HEX, the first flow valve RV1 for the secondary heat exchange section 14b, the second flow valve RV2 for the secondary heat exchanger 13b of the heat storage tank STR, and the bypass flow valve. It is composed of BV.

The heat storage tank STR includes water 16 and 1 which are heat storage materials.
The secondary side heat exchange section 13a, the secondary side heat exchange section 13b,
The pump unit PU includes a second four-way valve 3b and a refrigerant transfer pump PM.

In the above-described structure, the primary side refrigeration cycle includes the compressor 2, the first four-way valve 3a, the outdoor heat exchanger 4, the first expansion valve 5a, the primary side heat exchange of the refrigerant-refrigerant heat exchanger HEX. The parts 14a are sequentially connected in an annular shape, and a series connection circuit of the second expansion valve 5b and the primary side heat exchange part 13a of the heat storage tank STR is connected,
The first expansion valve 5a and the refrigerant-to-refrigerant heat exchanger HEX are connected in parallel to the series connection circuit of the primary side heat exchange section 14a.

In the secondary side refrigeration cycle, the pump unit PU, the two indoor units 12a and 12b, the secondary side heat exchange section 14b of the refrigerant / refrigerant heat exchanger HEX, and the first unit.
A series connection circuit with the flow valve RV1 and a series connection circuit with the secondary side heat exchange section 13b in the heat storage tank STR and the second flow valve RV2 connected in parallel are connected in an annular shape, and the refrigerant pair is further connected. Anti-first of the secondary side heat exchange section 14b of the refrigerant heat exchanger HEX
A bypass circuit that connects the flow valve side and the second flow valve RV2 side of the secondary side heat exchange section 13b in the heat storage tank STR via the bypass valve BV is provided.

Then, the defrost control device CN includes the pipe temperature sensor TS of the first four-way valve 3a, the first flow valve RV1, the second flow valve RV2, the bypass valve BV, and the outdoor heat exchanger 4.
It is connected with the signal line.

In this defrost control device CN, the bypass valve BV
By controlling the opening and closing of the valve, and controlling the opening of the first flow valve RV1 and the second flow valve RV2, it is possible to control the refrigerant circulation amount flowing into the secondary heat exchange section 14b of the refrigerant-refrigerant heat exchanger HEX. That is, the defrosting ability of the outdoor heat exchanger 4 can be controlled.

Next, the operation of the structure of this embodiment will be described in the following cases. (1) Nighttime heat storage operation Compressor 2, first four-way valve 3a, outdoor heat exchanger 4, second expansion valve 5b, primary side heat exchange section 14a of refrigerant-to-refrigerant heat exchanger HEX, inside heat storage tank STR In the primary side refrigeration cycle that communicates with the primary side heat exchange section 13a, the first four-way valve 3a:
Heating mode, first expansion valve 5a: fully closed, second expansion valve 5b:
By setting a predetermined opening degree and flowing the refrigerant as shown by the black arrow in FIG. 1, the heat storage operation is performed in which the water 16 as the heat storage material is heated through the primary side heat exchange section 13a in the heat storage tank. . (2) Nighttime defrosting operation When a frosting phenomenon occurs in the outdoor heat exchanger 4 in the heat storage operation at low outdoor temperature, when the pipe temperature sensor TS of the outdoor heat exchanger 4 detects a temperature equal to or lower than a predetermined temperature, Reverse cycle operation is performed in the primary side refrigeration cycle to perform night defrosting operation.

That is, in the primary side refrigeration cycle,
First four-way valve 3a: cooling mode, first expansion valve 5a: fully closed,
Second expansion valve 5b: The primary side heat exchange section 13a in the heat storage tank is set to an evaporator and an outdoor heat exchanger by setting a predetermined opening degree and flowing a refrigerant as shown by a white arrow in FIG. A refrigerating cycle is constituted by using 4 as a condenser, and heat is taken from warm water to defrost the outdoor heat exchanger 4.

When the pipe temperature sensor TS rises above the predetermined temperature, the defrosting operation ends and the night heat storage operation is resumed. (3) Daytime heating operation In this case, the defrosting control device CN controls so that the action differs depending on the temperature of the hot water in the heat storage tank STR.

A) When the water temperature in the heat storage tank is Tw ≧ Tmin (heating use limit temperature) During the daytime heating operation, the pump unit PU and the indoor unit 1 are used.
2a, 12b, the secondary heat exchanger 13b of the heat storage tank STR,
And the secondary heat exchanger 14b of the refrigerant-to-refrigerant heat exchanger HEX
2nd four-way valve: heating mode, first flow valve RV1, second flow valve RV2: predetermined, bypass valve BV: closed, as indicated by the black arrow in FIG. Heat storage tank S stored as hot water in heat storage operation
The heat quantity in TR is conveyed to the indoor units 12a and 12b via the secondary side heat exchanger 13b of the heat storage tank, and the room is heated.

At the same time, in order to improve the heating capacity, the primary side heat exchanger 14a of the refrigerant-refrigerant heat exchanger HEX is operated as a condenser in the primary-side refrigeration cycle to operate the refrigerant-refrigerant heat exchanger HEX and the heat storage tank. The refrigerant in the secondary side refrigeration cycle is heated in parallel with the STR.

B) In the case of water temperature Tw <Tmin (heat use limit temperature) in the heat storage tank In the daytime heating operation in this case, since the water temperature of the heat storage tank STR is lower than the limit temperature that can be used for heating, the heat storage tank ST
R is not used for indoor heating.

That is, in the secondary refrigeration cycle comprising the pump unit PU, the indoor units 12a and 12b, the secondary heat exchanger 13b of the heat storage tank, and the secondary heat exchanger 14b of the refrigerant-refrigerant heat exchanger HEX. , Second four-way valve: heating mode, first flow valve RV1: predetermined opening, second flow valve RV
2: Fully closed, bypass valve BV: closed, and as shown by the white arrow in FIG. 2, the amount of heat absorbed from the outdoor side is passed through the refrigerant-refrigerant heat exchanger HEX to the indoor units 12a, 12b.
It is transported to and the room is heated. (4) Daytime defrosting operation When a frosting phenomenon occurs in the outdoor heat exchanger 4 even in the heating operation at low outdoor temperature, if the pipe temperature sensor TS of the outdoor heat exchanger 4 detects a temperature equal to or lower than a predetermined temperature. The reverse cycle operation is performed in the primary side refrigeration cycle to perform the daytime defrosting operation.

In this case as well, the defrosting control device CN controls so that the action differs depending on the temperature of the hot water in the heat storage tank STR.

A) Water temperature in the heat storage tank Tw ≧ Tmin (limit temperature for heating use) In the defrosting operation of the outdoor heat exchanger 4, the bypass valve B
V: open, first flow valve RV1, second flow valve RV2: as a predetermined opening, as shown by the black arrow in FIG. 3, primary refrigeration cycle: reverse refrigeration cycle, and secondary refrigeration cycle: heating operation Operate in a cycle.

That is, the secondary heat exchanger 13 of the heat storage tank STR.
b and refrigerant-to-refrigerant heat exchanger HEX secondary heat exchanger 14b
The heating operation is continued with and in series.

That is, the amount of heat as hot water in the heat storage tank STR is heat-exchanged with the refrigerant via the secondary side heat exchanger 13b of the heat storage tank STR, but thereafter, the frost attached to the outdoor heat exchanger 4 Refrigerant-to-refrigerant heat exchanger HEX 2 for defrosting
The heat is absorbed by the secondary heat exchanger 14b.

Therefore, although the amount of heat transferred to the indoor units 12a, 12b is reduced and the heating capacity is somewhat lowered, the defrosting operation does not absorb heat from the indoor air and the comfort during heating may be impaired. Disappear.

B) Water temperature Tw in the heat storage tank is To (outside air temperature) <
When Tw <Tmin (heating use limit temperature) In the defrosting operation of the outdoor heat exchanger 4, the first expansion valve 5
a: Fully closed, second flow valve RV2: With a predetermined opening, the primary side refrigeration cycle is operated as a reverse refrigeration cycle, and the secondary side refrigeration cycle is not operated, as indicated by the white arrow in FIG.

That is, since the water temperature of the heat storage tank STR is lower than the limit temperature that can be used for heating, the heat storage tank STR is not used for indoor heating, but is used only for defrosting because it is higher than the outside air temperature.

In the primary side refrigeration cycle, by setting the first four-way valve 3a: cooling mode, the first expansion valve 5a: fully closed, and the second expansion valve 5b: predetermined opening degree A refrigerating cycle is configured by using the secondary heat exchanger 13a as an evaporator and the outdoor heat exchanger 4 as a condenser, and the outdoor heat exchanger 4 can be efficiently defrosted by absorbing heat from warm water.

[0048]

As described above, according to the present invention, in the heat storage type air conditioning air conditioner including the primary side refrigeration cycle and the secondary side refrigeration cycle through the refrigerant-refrigerant heat exchanger and the heat storage tank. A bypass circuit for connecting the refrigerant-refrigerant heat exchanger and the heat storage tank in the side refrigeration cycle in series via a bypass valve is installed.

Therefore, even during the daytime defrosting operation, the amount of heat transferred to the indoor unit is reduced and the heating capacity is somewhat reduced, but the defrosting operation does not absorb heat from the room air and the comfort during heating is improved. Will not be damaged.

In the defrosting operation of the outdoor heat exchanger when the heat storage material in the heat storage tank is at a predetermined temperature or higher, the bypass valve is opened to operate the primary side refrigeration cycle and the secondary side refrigeration cycle, In addition, in the defrosting operation of the outdoor heat exchanger when the heat storage material is below a predetermined temperature, a defrosting control device that operates only the primary side refrigeration cycle with the bypass valve closed is installed.

Therefore, the use can be divided according to the remaining amount of heat stored by using night power.
Effective use of electric power can be achieved.

[Brief description of drawings]

FIG. 1 is a refrigeration system diagram of a heat storage type air conditioner according to an embodiment of the present invention during winter night operation.

FIG. 2 is a refrigeration system diagram during a winter daytime heating operation of the heat storage type air conditioner according to an embodiment of the present invention.

FIG. 3 is a refrigeration system diagram during a winter daytime defrosting operation of the heat storage type air conditioner according to an embodiment of the present invention.

[Fig. 4] Fig. 4 is a refrigeration system diagram of a conventional heat storage type air conditioner during winter night operation.

[Fig. 5] Fig. 5 is a refrigeration system diagram of a conventional heat storage type air conditioner during winter daytime operation.

[Explanation of symbols]

2 compressor 3a 1st four-way valve 3b Second four-way valve 4 Outdoor heat exchanger 5a First expansion valve 5b Second expansion valve 12a, 12b Indoor unit 13a Primary heat exchange part of heat storage tank 13b Secondary heat exchange section of heat storage tank 14a Primary side heat exchange part of refrigerant-refrigerant heat exchanger 14b Secondary-side heat exchange section of refrigerant-refrigerant heat exchanger STR heat storage tank HEX refrigerant to refrigerant heat exchanger PM refrigerant transfer pump RV1 first flow valve RV2 second flow valve BV bypass valve CN defrost control device

─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Kazuhiko Machida 3-22 Takaidahondori, Higashi-Osaka City, Osaka Prefecture Matsushita Refrigerator Co., Ltd. (72) Inventor Kozo Suzuki 2-32 Kandajinbocho, Chiyoda-ku, Tokyo TEPCO Ltd. Development Laboratory (72) Inventor Yoshihide Sugita 2-30 Kanda Jimbocho, Chiyoda-ku, Tokyo TEPCO Development Laboratory (56) Reference Japanese Patent Laid-Open No. 5-118690 (JP, A) Kaihei 5-346247 (JP, A) JP-A-3-84370 (JP, A) JP-A-4-270876 (JP, A) (58) Fields investigated (Int.Cl. ⁷ , DB name) F24F 11 / 02 102 F25B 13/00 104 F25B 13/00 351

Claims (2)

(57) [Claims] 1. A compressor, a first four-way valve, an outdoor heat exchanger,
The first expansion valve, the primary side heat exchange section of the refrigerant-to-refrigerant heat exchanger including the primary side heat exchange section and the secondary side heat exchange section are sequentially connected in an annular shape, and the second expansion valve and the primary side heat exchange section are connected. A series connection circuit of a primary side heat exchange part of a heat storage tank composed of an exchange part, a secondary side heat exchange part, and a heat storage material is connected to the first expansion valve and the primary side heat of the refrigerant-refrigerant heat exchanger. A primary side refrigeration cycle connected in parallel to a series connection circuit with an exchange section, a pump unit including a refrigerant transfer pump and a second four-way valve, a plurality of indoor units, and a refrigerant-refrigerant heat exchanger. An annular series connection circuit of the secondary side heat exchange section and the first flow valve and a parallel connection of the secondary side heat exchange section in the heat storage tank and the series connection circuit of the second flow rate valve And a secondary side refrigeration cycle connected to the second side heat exchange section of the refrigerant-refrigerant heat exchanger.
A heat storage type air conditioner provided with a bypass circuit that connects a flow valve side and a second flow valve side of the secondary side heat exchange section in the heat storage tank via a bypass valve. 2. In the defrosting operation of the outdoor heat exchanger when the heat storage material in the heat storage tank has a predetermined temperature or higher, the bypass valve is opened to operate the primary side refrigeration cycle and the secondary side refrigeration cycle, In addition, in the defrosting operation of the outdoor heat exchanger when the heat storage material is below a predetermined temperature, a defrosting control device that operates only the primary side refrigeration cycle with the bypass valve closed is installed. Harmony machine.