U.S. patent application number 14/991247 was filed with the patent office on 2016-07-14 for air conditioner and method for controlling an air conditioner.
The applicant listed for this patent is LG ELECTRONICS INC.. Invention is credited to Song CHOI, Minho CHUNG, Hojong JEONG, Kwangho SHIN.
Application Number | 20160201952 14/991247 |
Document ID | / |
Family ID | 55077439 |
Filed Date | 2016-07-14 |
United States Patent
Application |
20160201952 |
Kind Code |
A1 |
JEONG; Hojong ; et
al. |
July 14, 2016 |
AIR CONDITIONER AND METHOD FOR CONTROLLING AN AIR CONDITIONER
Abstract
An air conditioner and a method for controlling an air
conditioner are provided. The air conditioner may include at least
one indoor device; an electric heat pump (EHP) outdoor device
connected to the at least one indoor device, configured to drive a
first compressor using electric power, and having a first outdoor
heat exchanger for heat exchange with a refrigerant; a gas heat
pump (GHP) outdoor device connected in parallel with the EHP
outdoor device, connected to the at least one indoor device, and
having an engine configured to drive a second compressor using a
burned gas, a second outdoor heat exchanger for heat exchange with
the refrigerant, and a waste heat exchanger configured to exchange
heat with the refrigerant using waste heat of the engine; and a
controller configured to control a warming operation or a
defrosting operation of the EHP outdoor device and the GHP outdoor
device, and to supply a high pressure refrigerant from the second
compressor of the GHP outdoor device to the EHP outdoor device
while the EHP outdoor device performs the defrosting operation.
Inventors: |
JEONG; Hojong; (Seoul,
KR) ; SHIN; Kwangho; (Seoul, KR) ; CHUNG;
Minho; (Seoul, KR) ; CHOI; Song; (Seuol,
KR) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
LG ELECTRONICS INC. |
Seoul |
|
KR |
|
|
Family ID: |
55077439 |
Appl. No.: |
14/991247 |
Filed: |
January 8, 2016 |
Current U.S.
Class: |
62/115 ;
62/160 |
Current CPC
Class: |
F25B 2400/06 20130101;
F25B 2400/05 20130101; F25B 47/02 20130101; F25B 27/02 20130101;
F25B 13/00 20130101; Y02A 30/274 20180101 |
International
Class: |
F25B 13/00 20060101
F25B013/00 |
Foreign Application Data
Date |
Code |
Application Number |
Jan 12, 2015 |
KR |
10-2015-0004275 |
Claims
1. An air conditioner, comprising: at least one indoor device; an
electric heat pump (EHP) outdoor device connected to the at least
one indoor device, configured to drive a first compressor using
electric power, and having a first outdoor heat exchanger that
performs heat exchange with a refrigerant; a gas heat pump (GHP)
outdoor device connected in parallel with the EHP outdoor device,
connected to the at least one indoor device, and including an
engine configured to drive a second compressor using a burned gas,
a second outdoor heat exchanger that performs heat exchange with
the refrigerant, and a waste heat exchanger configured to exchange
heat with the refrigerant using waste heat of the engine; and a
controller configured to control a warming operation or a
defrosting operation of the EHP outdoor device and the GHP outdoor
device, and to supply a high pressure refrigerant from the second
compressor of the GHP outdoor device to the EHP outdoor device
while the EHP outdoor device performs the defrosting operation.
2. The air conditioner according to claim 1, wherein the controller
switches the EHP outdoor device to perform the defrosting operation
when it is determined that the first outdoor heat exchanger of the
EHP outdoor device is covered with frost while the EHP outdoor
device and the GHP outdoor device perform the warming
operation.
3. The air conditioner according to claim 2, wherein the EHP
outdoor device includes a first four-way valve, which is switched
to an EHP warming mode during which the first compressor is
connected with the at least one indoor device when the EHP outdoor
device performs the warming operation, and which is switched to an
EHP defrosting mode during which the first compressor is connected
with the second compressor when the EHP outdoor device performs the
defrosting operation.
4. The air conditioner according to claim 3, wherein when the EHP
outdoor device performs the defrosting operation, the controller
switches the first four-way valve to the EHP defrosting mode, and
supplies the high pressure refrigerant of the second compressor to
the first compressor.
5. The air conditioner according to claim 3, wherein the GHP
outdoor device includes: an outdoor heat exchanger control valve
configured to control a flow of the refrigerant flowing into the
second outdoor heat exchanger; and a waste heat exchanger control
valve configured to control a flow of the refrigerant flowing into
the waste heat exchanger.
6. The air conditioner according to claim 5, wherein, when the EHP
outdoor device performs the defrosting operation, the controller
closes the outdoor heat exchanger control valve of the GHP outdoor
device, and opens the waste heat exchanger control valve.
7. The air conditioner according to claim 2, further including a
temperature sensor provided on the first outdoor heat exchanger and
configured to detect a temperature of the first outdoor heat
exchanger.
8. The air conditioner according to claim 2, wherein the controller
performs the defrosting operation of the EHP outdoor device at a
predetermined frosting temperature difference, and switches the
defrosting operation of the EHP outdoor device to a warming
operation thereof at a predetermined defrosting completion
temperature.
9. The air conditioner according to claim 8, wherein the
predetermined frosting temperature difference is a temperature
difference between an external air temperature and a temperature of
the first outdoor heat exchanger.
10. The air conditioner according to claim 8, wherein the
predetermined defrosting completion temperature is a temperature at
which the temperature of the first outdoor heat exchanger is about
10.degree. C. or more.
11. A method for controlling an air conditioner including at least
one indoor device, an EHP outdoor device connected to the at least
one indoor device and configured to drive a first compressor using
electric power, and a GHP outdoor device connected in parallel with
the EHP outdoor device, connected to the at least one indoor device
and having an engine configured to drive a second compressor using
a burned gas, the control method comprising: performing a warming
operation of the EHP outdoor device and the GHP outdoor device;
switching the EHP outdoor device to perform a defrosting operation
when the EHP outdoor device reaches a predetermined frosting
temperature; and supplying a high pressure refrigerant from the GHP
outdoor device to the EHP outdoor device.
12. The method according to claim 11, wherein, in the supplying of
the high pressure refrigerant from the GHP outdoor device to the
EHP outdoor device, a two-stage compression cycle in which the high
pressure refrigerant from the GHP outdoor device is compressed by
the compressor of the GHP outdoor device and then compressed by the
compressor of the EHP outdoor device is formed.
13. The method according to claim 11, further including switching
the EHP outdoor device to perform a warming operation when the EHP
outdoor device reaches a predetermined defrosting completion
temperature.
14. The method according to claim 11, wherein the predetermined
frosting temperature difference is a temperature difference between
an external air temperature and a temperature of a first outdoor
heat.
15. The method according to claim 13, wherein the predetermined
defrosting completion temperature is a temperature at which the
temperature of the first outdoor heat exchanger is about 10.degree.
C. or more.
16. The method according to claim 11, wherein the EHP outdoor
device includes a first four-way valve, which is switched to an EHP
warming mode during which the first compressor is connected with
the at least one indoor device when the EHP outdoor device performs
the warming operation, and which is switched to an EHP defrosting
mode during which the first compressor is connected with the second
compressor of the GHP outdoor device when the EHP outdoor device
performs the defrosting operation.
17. The method according to claim 16, wherein the GHP outdoor
device includes: an outdoor heat exchanger control valve configured
to control a flow of the refrigerant flowing into the second
outdoor heat exchanger; and a waste heat exchanger control valve
configured to control a flow of the refrigerant flowing into the
waste heat exchanger.
18. The method according to claim 17, further including closing the
outdoor heat exchanger control valve, and opening the waste heat
exchanger control valve when the EHP outdoor device performs the
defrosting operation.
19. The method according to claim 11, wherein the first outdoor
heat exchanger includes a temperature sensor configured to detect a
temperature of the first outdoor heat exchanger.
20. An air conditioner, comprising: at least one indoor device; an
electric heat pump (EHP) outdoor device connected to the at least
one indoor device, configured to drive a first compressor using
electric power, and having a first outdoor heat exchanger that
performs heat exchange with a refrigerant, and a first four-way
valve; a gas heat pump (GHP) outdoor device connected in parallel
with the EHP outdoor device, connected to the at least one indoor
device, and including an engine configured to drive a second
compressor using a burned gas, a second outdoor heat exchanger that
performs heat exchange with the refrigerant, and a waste heat
exchanger configured to exchange heat with the refrigerant using
waste heat of the engine; and a controller configured to control a
warming operation or a defrosting operation of the EHP outdoor
device and the GHP outdoor device, and to supply a high pressure
refrigerant from the second compressor of the GHP outdoor device to
the EHP outdoor device while the EHP outdoor device performs the
defrosting operation by controlling the first four-way valve to
supply the high pressure refrigerant from the second compressor to
the first compressor, the first outdoor heat exchanger, and the
waste heat exchanger.
21. The air conditioner according to claim 20, wherein the
controller switches the EHP outdoor device to perform the
defrosting operation when it is determined that the first outdoor
heat exchanger of the EHP outdoor device is covered with frost
while the EHP outdoor device and the GHP outdoor device perform the
warming operation.
22. The air conditioner according to claim 21, wherein the GHP
outdoor device includes: an outdoor heat exchanger control valve
configured to control a flow of the refrigerant flowing into the
second outdoor heat exchanger; and a waste heat exchanger control
valve configured to control a flow of the refrigerant flowing into
the waste heat exchanger.
23. The air conditioner according to claim 22, wherein, when the
EHP outdoor device performs the defrosting operation, the
controller closes the outdoor heat exchanger control valve of the
GHP outdoor device, and opens the waste heat exchanger control
valve.
Description
CROSS-REFERENCE TO RELATED APPLICATION(S)
[0001] This application claims priority under 35 U.S.C. .sctn.119
to Korean Application No. 10-2015-0004275, filed in Korea on Jan.
12, 2015, whose entire disclosure is hereby incorporated by
reference.
BACKGROUND
[0002] 1. Field
[0003] An air conditioner and a method for controlling an air
conditioner are disclosed herein.
[0004] 2. Background
[0005] An air conditioner is an apparatus that cools, warms, or
purifies indoor air to provide a more comfortable indoor
environment for a user. An air conditioner may be classified as an
electric heat pump (EHP) type, which uses electric power or a gas
heat pump (GHP) type, which uses a gas fuel, such as liquid
petroleum gas (LPG) and liquefied natural gas (LNG), according to a
power source for driving a compressor. In a GHP type, an engine is
operated by burning a gas fuel, and thus, a compressor is
driven.
[0006] A conventional EHP type air conditioner is disclosed in
Korean Patent Application No. 10-2003-0077857, which is hereby
incorporated by reference. Such a conventional air conditioner
includes a single outdoor unit or device or a combination of a
plurality of outdoor units or devices. In the conventional air
conditioner in which a plurality of EHP type outdoor units are
combined, when an outdoor heat exchanger is covered with frost due
to freezing, for example, a warming operation is stopped, and a
defrosting operation is performed. Therefore, in the conventional
air conditioner, there is a problem in that the warming operation
is stopped while the defrosting operation is performed.
BRIEF DESCRIPTION OF THE DRAWINGS
[0007] Embodiments will be described in detail with reference to
the following drawings in which like reference numerals refer to
like elements, and wherein:
[0008] FIG. 1 is a schematic diagram of an air conditioner
according to an embodiment;
[0009] FIG. 2 is a schematic diagram illustrating an operation of
the air conditioner of FIG. 1;
[0010] FIG. 3 is a graph Illustrating a two-stage compression cycle
of the air conditioner of FIG. 1;
[0011] FIG. 4 is a graph Illustrating a continuous warming
operation of the air conditioner of FIG. 1; and
[0012] FIG. 5 is a flowchart of a method for controlling an air
conditioner according to an embodiment.
DETAILED DESCRIPTION
[0013] In the following detailed description of embodiments,
reference is made to the accompanying drawings that form a part
hereof, and in which is shown by way of illustration embodiments
which may be practiced. These embodiments are described in
sufficient detail to enable those skilled in the art to practice
the embodiments, and it is understood that other embodiments may be
utilized and that logical structural, mechanical, electrical, and
chemical changes may be made without departing from the spirit or
scope. To avoid detail not necessary to enable those skilled in the
art to practice the embodiments, the description may omit certain
information known to those skilled in the art. The following
detailed description is, therefore, not to be taken in a limiting
sense, and the scope is defined only by the appended claims.
[0014] FIG. 1 is a schematic diagram of an air conditioner
according to an embodiment. Referring to FIG. 1, the air
conditioner 1 may include an indoor unit or device 10 and an
outdoor unit or device 100. One or a plurality of indoor units 10
may be provided. The one or more indoor units 10 may be connected
with the outdoor unit 100, and may cool, warm, or purify indoor
air.
[0015] The indoor unit 10 may include a pair of indoor unit pipes
12 and 14 for connection with the outdoor unit 100. The pair of
indoor unit pipes 12 and 14 may include a first indoor unit pipe 12
that connects an EHP outdoor unit or device 200 and a GHP outdoor
unit or device 300, which will be described hereinafter, and a
second indoor unit pipe 14 that connects the EHP outdoor unit 200
and the GHP outdoor unit 300, which will be described
hereinafter.
[0016] The outdoor unit 100 may be connected with the one or more
indoor unit 10, and may perform compressing and expanding, for
example, of a refrigerant to allow a sufficient heat exchanging
operation of the indoor unit 10. A plurality of outdoor units 100
may be provided. Hereinafter, as an example, an embodiment having
one pair of outdoor units 100 will be described.
[0017] The outdoor unit 100 may be a combined type including an
electric heat pump (EHP) type using electric power and a gas heat
pump (GHP) type using a gas fuel, such as LPG and LNG. The outdoor
unit 100 may include a first connection valve 110, a second
connection valve 120, the EHP outdoor unit 200, the GHP outdoor
unit 300, and a controller 500. The first connection valve 110 may
be connected with the first indoor unit pipe 12 of the indoor unit
10 to transfer a high pressure refrigerant from the outdoor unit
100 to the indoor unit 10 in a warming operation. The second
connection valve 120 may be connected with the second indoor unit
pipe 14 of the indoor unit 10 to transfer a low pressure
refrigerant from the indoor unit 10 to the outdoor unit 100 in the
warming operation.
[0018] The EHP outdoor unit 200 may be an outdoor unit operated
using an EHP method, and may include a first compressor 210, a
first accumulator 220, a first outdoor heat exchanger 250, a
temperature sensor 255, a first outdoor heat exchanger control
valve 260, and a first four-way valve 270. The first compressor 210
may compress the refrigerant, and may be driven by applying a
voltage. When the voltage is applied to the first compressor 210,
the first compressor 210 may compress the refrigerant.
[0019] The first accumulator 220 may supply the refrigerant to the
first compressor 210. When the refrigerant flows backward or is
introduced into the first compressor 210 as a liquid, the first
compressor 210 may be damaged, and thus, the first accumulator 220
may temporarily store a mixture of oil and the refrigerant.
[0020] The first outdoor heat exchanger 250 may evaporate or
condense the refrigerant according to a cooling operation or a
warming operations of the air conditioner 1. When the air
conditioner 1 performs the cooling operation, the refrigerant may
be condensed, and when the air conditioner 1 performs the warming
operation, the refrigerant may be evaporated.
[0021] The temperature sensor 255 may detect a temperature of the
first outdoor heat exchanger 250. The temperature sensor 255 may be
provided at or in the first outdoor heat exchanger 250. The
temperature sensor 255 may be one of various temperature sensors
that detect a temperature. The first outdoor heat exchanger control
valve 260 may control a flow of the refrigerant to the first
outdoor heat exchanger 250. As the first outdoor heat exchanger
control valve 260 is well known, detailed description thereof has
been omitted.
[0022] The first four-way valve 270 may switch a passage of the
refrigerant flowing in the EHP outdoor unit 200. According to
on/off of electric power, the first four-way valve 270 may be
switched to an EHP warming mode, in which the indoor unit 10 may be
connected with the first compressor 210 when the EHP outdoor unit
200 performs the warming operation, and an EHP defrosting mode or
an EHP cooling mode, in which the first compressor 210 may be
connected with the second compressor 310 of the GHP outdoor unit
300, which will be described hereinafter, when the EHP outdoor unit
200 performs the defrosting operation. More specifically, the first
four-way valve 270 may be switched to the EHP warming mode when the
electric power is supplied, and may be switched to the EHP
defrosting mode or the EHP warning mode when the electric power is
not supplied.
[0023] The GHP outdoor unit 300 may be an outdoor unit operated
using a GHP method, and may include a second compressor 310, a
second accumulator 320, an engine 330, a cooling water heat
exchanger 340, a cooling water pump 345, a second outdoor heat
exchanger 350, a second outdoor heat exchanger control valve 355, a
waste heat exchanger 370, a waste heat exchanger control valve 375,
and a second four-way valve 380. The second compressor 310 may
compress the refrigerant, and may be operated through driving of
the engine 330, which will be described hereinafter. When a driving
force is transmitted to the second compressor 310 by the engine
330, the second compressor 310 may compress the refrigerant,
similar to the first compressor 210.
[0024] The second accumulator 320 may supply the refrigerant to the
second compressor 310. When the refrigerant flows backwards or is
introduced into the second compressor 310 as a liquid, the second
compressor 310 may be damaged, and thus, the second accumulator 320
may temporarily store the mixture of oil and the refrigerant,
similar to the first accumulator 220. The engine 330 may transmit
the driving force to the second compressor 310, and may be operated
by burning of the gas fuel, such as LPG and LNG. The GHP outdoor
unit 300 may be operated using the GHP method using the burned gas
from the engine 330.
[0025] The cooling water heat exchanger 340 may cool the engine
330. The cooling water heat exchanger 340 may absorb heat of the
engine 330 overheated by driving of the engine 330 using cooling
water. The cooling water pump 345 may provide a flowing force to
the cooling water, and may be connected with the cooling water heat
exchanger 340. As the cooling water pump 345 is well known,
detailed description thereof has been omitted.
[0026] The second outdoor heat exchanger 350 may evaporate or
condense the refrigerant through the cooling and warming operations
of the air conditioner 1, similar to the first outdoor heat
exchanger 250. When the air conditioner 1 performs the cooling
operation, the refrigerant may be condensed, and when the air
conditioner 1 performs the warming operation, the refrigerant may
be evaporated.
[0027] The second outdoor heat exchanger control valve 355 may
control the flow of the refrigerant to the second outdoor heat
exchanger 350. The second outdoor heat exchanger control valve 355
may be opened when the EHP outdoor unit 200 performs the warming
operation, and may be closed when the EHP outdoor unit 200 performs
the defrosting operation or the cooling operation. The waste heat
exchanger 370 may evaporate or condense the refrigerant through the
cooling and warming operations of the air conditioner 1, similar to
the second outdoor heat exchanger 350. The waste heat exchanger 370
may be a plate type heat exchanger. The waste heat exchanger 370
may evaporate or condense the refrigerant together with the second
outdoor heat exchanger 350.
[0028] The waste heat exchanger control valve 375 may control the
flow of refrigerant to the waste heat exchanger 370. As the waste
heat exchanger control valve 375 is well known, detailed
description thereof has been omitted. The second four-way valve 380
may switch a passage of the refrigerant flowing in the GHP outdoor
unit 300. Similar to the first four-way valve 270, the second
four-way valve 380 may be switched to a GHP warming mode when the
electric power is supplied, and may be switched to a GHP cooling
mode when the electric power is not supplied.
[0029] The controller 500 may control an overall operation of the
outdoor unit 100, such as the cooling operation, the warming
operation, and the defrosting operation of the EHP outdoor unit 200
and the GHP outdoor unit 300. For example, when the EHP outdoor
unit 200 performs the defrosting operation, the controller 500 may
control the high pressure refrigerant from the second compressor
310 of the GHP outdoor unit 300 to be supplied to the EHP outdoor
unit 200.
[0030] The controller 500 may perform the defrosting operation of
the EHP outdoor unit 200 at a predetermined frosting temperature
difference. A temperature difference between an external air
temperature and a temperature of the first outdoor heat exchanger
250 may be set as the predetermined frosting temperature
difference. The controller 500 may perform the defrosting operation
of the EHP outdoor unit 200 when the predetermined frosting
temperature difference exceeds about 15.degree. C. This is only an
example, and the predetermined frosting temperature may be changed
properly according to design.
[0031] During the warming operation of the EHP outdoor unit 200 and
the GHP outdoor unit 300, when frosting of the first outdoor heat
exchanger 250 of the EHP outdoor unit 200 is detected, the
controller 500 may switch the warming operation of the EHP outdoor
unit 200 to the defrosting operation thereof. During the defrosting
operation of EHP outdoor unit 200, the controller 500 may switch an
operation mode of the first four-way valve 270 to the EHP
defrosting mode, and may connect the first compressor 210 with the
second compressor 310. The switching of the first four-way valve
270 may be performed according to on/off of the electric power
supplied to the first four-way valve 270. Further, in the
defrosting operation of the EHP outdoor unit 200, the controller
500 may close the second outdoor heat exchanger control valve 355,
and open the waste heat exchanger control valve 375.
[0032] When a predetermined defrosting completion temperature is
reached, the controller 500 may switch the defrosting operation of
the EHP outdoor unit 200 to the warming operation thereof. The
temperature of the first outdoor heat exchanger 250 may be set as
the predetermined defrosting completion temperature. The controller
500 may switch the defrosting operation of the EHP outdoor unit 200
to the warming operation when the predetermined defrosting
completion temperature is about 10.degree. C. or more. This is only
an example, and the predetermined defrosting completion temperature
may be changed properly according to design.
[0033] As described above, the controller 500 may control the
overall operation of the outdoor unit 100 of the air conditioner 1.
Hereinafter, an operation of the air conditioner 1 according to an
embodiment will be described.
[0034] FIG. 2 is a schematic diagram illustrating an operation of
the air conditioner of FIG. 1. FIG. 3 is a graph illustrating a
two-stage compression cycle of the air conditioner of FIG. 1. FIG.
4 is a graph illustrating a continuous warming operation of the air
conditioner of FIG. 1.
[0035] Referring to FIGS. 2 to 4, during the warming operation of
the air conditioner 1, when frosting of the first outdoor heat
exchanger 250 of the EHP outdoor unit 200 due to freezing, for
example, is detected, the controller 500 may switch the operation
of EHP outdoor unit 200 to the defrosting operation. A frosting
detecting temperature difference may be designed as, for example,
the above-described temperature difference at which the temperature
difference between the external air temperature and the temperature
of the first outdoor heat exchanger 250 exceeds about 15.degree. C.
The temperature of the first outdoor heat exchanger 250 may be
detected by the temperature sensor 255.
[0036] In the defrosting operation of the EHP outdoor unit 200, the
controller 500 may cut off the electric power supply to the first
four-way valve 270, and may control the first four-way valve 270 to
connect the first outdoor heat exchanger 250 with the second
outdoor heat exchanger 350. The controller 500 may control the GHP
outdoor unit 300 to continuously perform the warming operation,
close the second outdoor heat exchanger control valve 355 of the
second outdoor heat exchanger 350, and open the waste heat
exchanger control valve 375. As described above, the opening and
closing of the second outdoor heat exchanger control valve 355 and
the waste heat exchanger control valve 375 may be performed
automatically.
[0037] The flow of the refrigerant may be as follows. The
refrigerant compressed by and flowing from the second compressor
310 of the GHP outdoor unit 300 may be branched to the first indoor
unit pipe 12 of the indoor unit 10 and the EHP outdoor unit 200
through the second four-way valve 380. The refrigerant branched to
the EHP outdoor unit 200 may flow into the first four-way valve
270, the first accumulator 220, and the first compressor 210. The
refrigerant flowing into the first compressor 210 may be compressed
again by the first compressor 210, and then may flow to the first
outdoor heat exchanger 250 through the first four-way valve
270.
[0038] That is, as illustrated in FIG. 3, the refrigerant may be
compressed in two stages. The refrigerant compressed in two stages
may pass through the first outdoor heat exchanger 250, and then may
be introduced into the GHP outdoor unit 300. The temperature of the
first outdoor heat exchanger 250 may be reduced due to the passing
of the refrigerant therethrough. The refrigerant introduced into
the GHP outdoor unit 300 may then be introduced again into the
second compressor 310 via the opened waste heat exchanger control
valve 375, the waste heat exchanger 370, and the second accumulator
320. The refrigerant introduced into the second compressor 310 may
be supplied to the indoor unit 10 and the EHP outdoor unit 200, as
previously described, and thus may form a circulation cycle.
[0039] When the refrigerant is primarily compressed to a
predetermined target high pressure completing the defrosting of the
first outdoor heat exchanger 250, the controller 500 may control a
rotating speed of the second compressor 310. That is, the
controller 500 may increase or reduce the rotating speed of the
second compressor 310 until the refrigerant reaches the
predetermined target high pressure. The predetermined target high
pressure may be about 2900 kPa. This is only an example, and the
predetermined target high pressure may be properly changed
according to design.
[0040] When the refrigerant is secondarily compressed, the
controller 500 may increase the rotating speed of the first
compressor 310. That is, the control unit 500 may increase the
rotating speed of the first compressor 310 to complete the
defrosting of the first outdoor heat exchanger 250 when the
refrigerant is secondarily compressed. When the refrigerant reaches
a defrosting temperature of the first outdoor heat exchanger 250
through the circulation circle, the controller 500 may again switch
the defrosting operation of the EHP outdoor unit 200 to the warming
operation thereof. The defrosting completion temperature may be a
temperature at which the temperature of the first outdoor heat
exchanger 250 is about 10.degree. C. or more. This is only an
example, and the temperature may be changed properly according to
design.
[0041] When the EHP outdoor unit 200 is switched to the warming
operation, the controller 500 may turn on the electric power supply
to the first four-way valve 270, and control the first four-way
valve 270 to connect the first compressor 210 to the indoor unit
10. Then, the outdoor unit 100 of the air conditioner 1, that is,
both of the EHP outdoor unit 200 and the GHP outdoor unit 300 may
perform the warming operation.
[0042] As described above, in the air conditioner 1 according to an
embodiment, when the EHP outdoor unit 200 performs the defrosting
operation, the GHP outdoor unit 300 may continuously perform the
warming operation through the waste heat exchanger 370 using the
waste heat of the engine 330. In the case of the GHP outdoor unit
300, even though the second outdoor heat exchanger 350 may be
covered with frost, the defrosting operation may not be required
due to the waste heat exchanger 370 using the waste heat of the
engine 330. Thus, in the air conditioner 1 according to an
embodiment, as illustrated in FIG. 4, even when the EHP outdoor
unit 200 performs the defrosting operation, the warming operation
may be continuously performed, and thus, the problem in which the
warming operation may be stopped due to the defrosting operation
may not occur.
[0043] As such, in the air conditioner 1 according to an
embodiment, even when the outdoor heat exchanger is covered with
frost due to freezing while the warming operation is performed, the
warming operation may be continuously performed through the GHP
outdoor unit 300 provided at a first stage side of a two-stage
compression cycle, and thus, warming efficiency may be remarkably
enhanced. Further, in the air conditioner 1 according to an
embodiment, the two-stage compression cycle may be formed when the
EHP outdoor unit 200 performs the defrosting operation, and the EHP
outdoor unit 200 side may serve as a high stage side cycle, and
thus, a defrosting time may be also reduced.
[0044] Hereinafter, a method for controlling an air conditioner
according to an embodiment will be described.
[0045] FIG. 5 is a flowchart of a method for controlling an air
conditioner according to an embodiment. Referring to FIG. 5, when a
warming operation is performed, the air conditioner, such as air
conditioner of FIG. 1, may switch on a first four-way valve of an
EHP outdoor unit, such as first-four way valve 270 of EHP outdoor
unit 200 of FIG. 1, and a second four-way valve of a GHP outdoor
unit, such as second four-way valve 380 of EHP outdoor unit 300 of
FIG. 1, so that both of the EHP outdoor unit and the GHP outdoor
unit may be performed in the warming mode (S10).
[0046] Then, the air conditioner may determine whether a first
outdoor heat exchanger, such as first outdoor heat exchanger 250 of
FIG. 1, is covered with frost (S20). Whether the first outdoor heat
exchanger is covered with frost is determined using a difference
between an external air temperature and a temperature of the first
outdoor heat exchanger. When the temperature difference between the
external air temperature and the temperature of the first outdoor
heat exchanger exceeds about 15.degree. C., it may be determined
that the first outdoor heat exchanger is covered with the
frost.
[0047] The air conditioner may switch off the first four-way valve
of the EHP outdoor unit and control the EHP outdoor unit to operate
in a defrosting mode upon determining that the first outdoor heat
exchanger is covered with frost. In a case of the GHP outdoor unit,
the air conditioner may maintain a state in which the second
four-way valve may be switched on, and thus, allow the GHP outdoor
unit to continuously operate in an EHP warming mode (S30). The air
conditioner may continuously switch on the first four-way valve of
the EHP outdoor unit and the second four-way valve of the GHP
outdoor unit and continuously perform the warming operation (S60)
upon determining that the first outdoor heat exchanger, such as
first outdoor heat exchanger is not covered with the frost.
[0048] The air conditioner may control a rotating speed of
compressors of an outdoor unit, such as first and second
compressors 210, 310 of outdoor unit 100 of FIG. 1, after the EHP
outdoor unit is switched to an EHP defrosting mode. More
specifically, the air conditioner may control a rotating speed of
the second compressor and an increase in the rotating speed of a
first compressor until it reaches a target high pressure (S40). As
previously described, in an embodiment, the two-stage compression
cycle may be formed through this process.
[0049] The air conditioner may determine whether defrosting of the
EHP outdoor unit is completed through the two-stage cycle operation
(S50). Whether the defrosting of the EHP outdoor unit is completed
may be determined based on whether the first outdoor heat exchanger
reaches the predetermined temperature. In one embodiment, when the
temperature of the first outdoor heat exchanger exceeds about
10.degree. C., it may be determined that the defrosting of the EHP
outdoor unit is completed.
[0050] The air conditioner may switch on the first four-way valve
again, and switch the EHP outdoor unit to be operated in the EHP
warming mode when it is determined that the defrosting of the EHP
outdoor unit is completed. In a case of the GHP outdoor unit, the
air conditioner may continuously maintain a state in which the
second four-way valve is switched on (S60). When it is determined
that the defrosting of the EHP outdoor unit is not completed, the
air conditioner may control the rotating speed of the compressors
(S50).
[0051] As described above, when the EHP outdoor unit performs the
defrosting operation, the air conditioner according to an
embodiment may continuously perform the warming operation, and may
also remarkably reduce a defrosting operation time of the EHP
outdoor unit using waste heat of the GHP outdoor unit.
[0052] An air conditioner capable of solving the above-described
problem, and a method for controlling an air conditioner is
provided according to embodiments disclosed herein.
[0053] Embodiments disclosed herein provide an air conditioner that
may include at least one indoor unit or device; an EHP outdoor unit
or device connected to the at least one indoor unit, configured to
drive a first compressor using electric power, and having a first
outdoor heat exchanger that performs heat exchange with a
refrigerant; a GHP outdoor unit or device connected in parallel
with the EHP outdoor unit, connected to the at least one indoor
unit, and having an engine configured to drive a second compressor
through a burned gas, a second outdoor heat exchanger that performs
heat exchange with the refrigerant, and a waste heat exchanger
configured to exchange heat with the refrigerant using waste heat
of the engine; and a controller configured to control a warming
operation or a defrosting operation of the EHP outdoor unit and the
GHP outdoor unit, and to supply a high pressure refrigerant from
the second compressor of the GHP outdoor unit to the EHP outdoor
unit while the EHP outdoor unit performs the defrosting
operation.
[0054] The controller may switch the EHP outdoor unit to perform
the defrosting operation when it is detected that the first outdoor
heat exchanger of the EHP outdoor unit is covered with frost while
the EHP outdoor unit and the GHP outdoor unit perform the warming
operation. The EHP outdoor unit may include a first four-way valve,
which may be switched to an EHP warming mode, which connects the
first compressor with the at least one indoor unit when the EHP
outdoor unit performs the warming operation, and is converted to an
EHP defrosting mode, which connects the first compressor with the
second compressor of the GHP outdoor unit, when the EHP outdoor
unit performs the defrosting operation. When the EHP outdoor unit
performs the defrosting operation, the controller may switch the
first four-way valve to the EHP defrosting mode, and may supply
high pressure refrigerant of the second compressor to the first
compressor.
[0055] The GHP outdoor unit may include a second outdoor heat
exchanger control valve configured to control a flow of the
refrigerant flowing into the second outdoor heat exchanger, and a
waste heat exchanger control valve configured to control a flow of
the refrigerant flowing into the waste heat exchanger. When the EHP
outdoor unit performs the defrosting operation, the controller may
close the second outdoor heat exchanger control valve, and may open
the waste heat exchanger control valve.
[0056] A temperature sensor configured to detect a temperature of
the first outdoor heat exchanger may be provided at the first
outdoor heat exchanger. The controller may perform the defrosting
operation of the EHP outdoor unit at a predetermined frosting
temperature, and may switch the defrosting operation of the EHP
outdoor unit to a warming operation thereof at a predetermined
defrosting completion temperature. The predetermined frosting
temperature may be a temperature at which a temperature difference
between an external air temperature and a temperature of the first
outdoor heat exchanger exceeds about 15.degree. C. The
predetermined defrosting completion temperature may be a
temperature at which the temperature of the first outdoor heat
exchanger is about 10.degree. C. or more.
[0057] Embodiments disclosed herein further provide a control
method of an air conditioner that may include at least one indoor
unit or device, an EHP outdoor unit or device connected to the at
least one indoor unit and configured to drive a first compressor
using electric power, and a GHP outdoor unit or device connected in
parallel with the EHP outdoor unit, connected to the at least one
indoor unit and having an engine used through a burned gas. The
control method may include performing a warming operation of the
EHP outdoor unit and the GHP outdoor unit; switching the EHP
outdoor unit to perform a defrosting operation when the EHP outdoor
unit reaches a predetermined frosting temperature; and supplying a
high pressure refrigerant of the GHP outdoor unit to the EHP
outdoor unit. In the supplying of the high pressure refrigerant of
the GHP outdoor unit to the EHP outdoor unit, a two-stage
compression cycle in which the high pressure refrigerant of the GHP
outdoor unit is compressed by the compressor of the GHP outdoor
unit and then compressed by the compressor of the EHP outdoor unit
may be formed.
[0058] The control method may include switching the EHP outdoor
unit to perform a warming operation when the EHP outdoor unit
reaches a predetermined defrosting completion temperature. The
predetermined frosting temperature may be a temperature at which a
temperature difference between an external air temperature and a
temperature of the first outdoor heat exchanger exceeds about
15.degree. C. The predetermined defrosting completion temperature
may be a temperature at which the temperature of the first outdoor
heat exchanger is about 10.degree. C. or more.
[0059] According to embodiments disclosed herein, when the EHP
outdoor unit performs the defrosting operation, the warming
operation may be continuously performed, and also the defrosting
operation time of the EHP outdoor unit may be remarkably reduced
using the waste heat of the GHP outdoor unit.
[0060] Even though all elements of embodiments may be coupled into
one or operated in the combined state, embodiments are not limited
to such embodiments. That is, all the elements may be selectively
combined with each other without departing the scope. Further, when
it is described that one comprises (or comprises or has) some
elements, it should be understood that it may comprise (or include
or have) only those elements, or it may comprise (or include or
have) other elements as well as those elements if there is no
specific limitation. Unless otherwise specifically defined herein,
all terms comprising technical or scientific terms are to be given
meanings understood by those skilled in the art. Like terms defined
in dictionaries, generally used terms needs to be construed as
meaning used in technical contexts and are not construed as ideal
or excessively formal meanings unless otherwise clearly defined
herein.
[0061] Any reference in this specification to "one embodiment," "an
embodiment," "example embodiment," etc., means that a particular
feature, structure, or characteristic described in connection with
the embodiment is included in at least one embodiment. The
appearances of such phrases in various places in the specification
are not necessarily all referring to the same embodiment. Further,
when a particular feature, structure, or characteristic is
described in connection with any embodiment, it is submitted that
it is within the purview of one skilled in the art to effect such
feature, structure, or characteristic in connection with other ones
of the embodiments.
[0062] Although embodiments have been described with reference to a
number of illustrative embodiments thereof, it should be understood
that numerous other modifications and embodiments can be devised by
those skilled in the art that will fall within the spirit and scope
of the principles of this disclosure. More particularly, various
variations and modifications are possible in the component parts
and/or arrangements of the subject combination arrangement within
the scope of the disclosure, the drawings and the appended claims.
In addition to variations and modifications in the component parts
and/or arrangements, alternative uses will also be apparent to
those skilled in the art.
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