U.S. patent application number 11/456679 was filed with the patent office on 2007-01-18 for cogeneration system.
This patent application is currently assigned to LG ELECTRONICS INC.. Invention is credited to Se Dong CHANG, Eun Jun CHO, Baik Young CHUNG, Sim Bok HA, Cheol Min KIM.
Application Number | 20070012058 11/456679 |
Document ID | / |
Family ID | 37660420 |
Filed Date | 2007-01-18 |
United States Patent
Application |
20070012058 |
Kind Code |
A1 |
CHO; Eun Jun ; et
al. |
January 18, 2007 |
COGENERATION SYSTEM
Abstract
A cogeneration system is constructed such that the waste heat
recovered from the engine is supplied to the heat pump type air
conditioner through the waste heat supplying heat exchanger,
thereby maximizing heating capacity and efficiency. A waste heat
supplying heat exchanger connecting conduit is formed so as to
guide a refrigerant emerging from an indoor unit to enter an
outdoor unit through the waste heat supplying heat exchanger, so
that the flow path between the waste heat supplying heat exchanger
and the heat pump type air conditioner is minimized, thereby
reducing installation costs and flow resistance.
Inventors: |
CHO; Eun Jun; (Buchun-si,
KR) ; HA; Sim Bok; (Kwangmyung-si, KR) ;
CHUNG; Baik Young; (Inchun-si, KR) ; KIM; Cheol
Min; (Seoul, KR) ; CHANG; Se Dong;
(Kwangmyung-si, KR) |
Correspondence
Address: |
GREENBLUM & BERNSTEIN, P.L.C.
1950 ROLAND CLARKE PLACE
RESTON
VA
20191
US
|
Assignee: |
LG ELECTRONICS INC.
20 Yeoeuido-dong, Youngdeungpo-ku,
Seoul
KR
|
Family ID: |
37660420 |
Appl. No.: |
11/456679 |
Filed: |
July 11, 2006 |
Current U.S.
Class: |
62/238.7 ;
62/238.6 |
Current CPC
Class: |
Y02B 30/52 20130101;
F25B 2313/023 20130101; F25B 2313/025 20130101; F25B 27/00
20130101; Y02E 20/14 20130101; F25B 13/00 20130101 |
Class at
Publication: |
062/238.7 ;
062/238.6 |
International
Class: |
F25B 27/00 20060101
F25B027/00 |
Foreign Application Data
Date |
Code |
Application Number |
Jul 12, 2005 |
KR |
2005-62778 |
Claims
1. A cogeneration system, comprising: a generator; a drive source
which operates to drive the generator, and generates heat; a waste
heat recovery unit which recovers the waste heat of the driving
source; a heat pump type air conditioner which is supplied with
electric power from the generator, and includes an indoor unit and
outdoor unit; a waste heat supplying heat exchanger which supplies
the heat recovered by the waste heat recovery unit to the heat pump
type air conditioner; and a waste heat supplying heat exchanger
connecting conduit adapted to guide a refrigerant emerging from the
indoor unit during a heating operation of the heat pump type air
conditioner to enter the outdoor unit through the waste heat
supplying heat exchanger.
2. The cogeneration system of claim 1, wherein the waste heat
supplying connecting conduit comprises an indoor unit connecting
conduit which connects the waste heat supplying heat exchanger and
the indoor unit and an outdoor unit connecting conduit which
connects the waste heat supplying heat exchanger and the outdoor
unit.
3. The cogeneration system of claim 1, wherein a first bypass
conduit is formed at the waste heat supplying heat exchanger
connecting conduit to guide the refrigerant emerging from the
outdoor unit during a cooling operation of the heat pump type air
conditioner to bypass the waste heat supplying heat exchanger.
4. The cogeneration system of claim 3, wherein a first non-return
valve is arranged at the first bypass conduit to prevent reverse
flow of the refrigerant emerging from the indoor unit during the
heating operation of the heat pump type air conditioner to the
first bypass conduit.
5. The cogeneration system of claim 1, wherein an expansion valve
is arranged at the waste heat supplying heat exchanger connecting
conduit to expand the refrigerant introduced into the waste heat
supplying heat exchanger during the heating operation of the heat
pump type air conditioner.
6. The cogeneration system of claim 5, wherein a second bypass
conduit is formed at the waste heat supplying heat exchanger
connecting conduit to bypass the expansion valve according to an
outdoor temperature, and a first heating valve is arranged at the
second bypass conduit to open and close the second bypass
conduit.
7. The cogeneration system of claim 1, wherein a second non-return
valve is arranged at the waste heat supplying heat exchanger
connecting conduit to prevent reverse flow of the refrigerant
emerging from the outdoor heat exchanger during the heating
operation of the heat pump type air conditioner to the waste heat
supplying heat exchanger.
8. The cogeneration system of claim 2, wherein the outdoor unit has
an outdoor heat exchanger connecting conduit for connecting the
outdoor unit connecting conduit and the outdoor heat exchanger and
a compressor connecting conduit for connecting the outdoor unit
connecting conduit and a suction side of the compressor in the
outdoor unit.
9. The cogeneration system of claim 8, wherein a second heating
valve is arranged at the compressor connecting conduit to open the
compressor connecting conduit when the heat pump type air
conditioner is in a heating mode and the outdoor temperature is
lower than a set temperature.
10. The cogeneration system of claim 8, wherein the outdoor heat
exchanger connecting conduit consists of a cooling path adapted to
guide the refrigerant passed through the outdoor heat exchanger
during a cooling operation of the heat pump type air conditioner to
flow therethough, and a heating path adapted to guide the
refrigerant passed through the waste heat supplying heat exchanger
to enter the outdoor heat exchanger when the heat pump type air
conditioner is in a heating mode and the outdoor temperature is
higher than a set temperature.
11. The cogeneration system of claim 8, wherein a cooling valve is
arranged at the cooling path to open the cooling path during the
cooling operation of the heat pump type air conditioner.
12. The cogeneration system of claim 8, wherein an outdoor
expansion valve is arranged at the heating path to expand the
refrigerant passing through the heating path.
13. A cogeneration system, comprising: a generator; a drive source
which operates to drive the generator, and generates heat; a
cooling water heat exchanger which recovers heat of cooling water
of the driving source; an exhaust gas heat exchanger which recovers
exhaust gas heat discharged from the driving source; a heat pump
type air conditioner which is supplied with electric power from the
generator, and includes an indoor unit and outdoor unit; a waste
heat supplying heat exchanger which supplies the heat recovered by
at least one of the waste heat recovery unit to at least one of the
cooling water heat exchanger and the exhaust gas heat exchanger;
and a waste heat supplying heat exchanger connecting conduit
adapted to guide a refrigerant emerging from the indoor unit during
a heating operation of the heat pump type air conditioner to enter
the outdoor unit through the waste heat supplying heat
exchanger.
14. The cogeneration system of claim 13, further comprising a
radiating heat exchanger which is installed to radiate the heat
recovered from at least one of the cooling water heat exchanger and
the exhaust gas heat exchanger.
15. The cogeneration system of claim 13, wherein the waste heat
supplying connecting conduit comprises an indoor unit connecting
conduit which connects the waste heat supplying heat exchanger and
the indoor unit and an outdoor unit connecting conduit which
connects the waste heat supplying heat exchanger and the outdoor
unit.
16. The cogeneration system of claim 15, wherein the outdoor unit
has an outdoor heat exchanger connecting conduit for connecting the
outdoor unit connecting conduit and the outdoor heat exchanger and
a compressor connecting conduit for connecting the outdoor unit
connecting conduit and a suction side of the compressor in the
outdoor unit.
17. The cogeneration system of claim 16, wherein the outdoor heat
exchanger connecting conduit consists of a cooling path adapted to
guide the refrigerant passed through the outdoor heat exchanger
during a cooling operation of the heat pump type air conditioner to
flow therethough, and a heating path adapted to guide the
refrigerant passed through the waste heat supplying heat exchanger
to enter the outdoor heat exchanger when the heat pump type air
conditioner is in a heating mode and the outdoor temperature is
higher than a set temperature.
18. The cogeneration system of claim 16, wherein a first bypass
conduit is formed between the outdoor unit connecting conduit and
the indoor unit connecting conduit to guide the refrigerant
emerging from the outdoor unit during a cooling operation of the
heat pump type air conditioner to bypass the waste heat supply heat
exchanger.
19. The cogeneration system of claim 16, wherein an expansion valve
is arranged at the waste heat supplying heat exchanger connecting
conduit to expand the refrigerant introduced into the waste heat
supplying heat exchanger during the heating operation of the heat
pump type air conditioner.
20. The cogeneration system of claim 19, wherein a second bypass
conduit is formed at the indoor unit connecting conduit to bypass
the expansion valve according to an outdoor temperature.
Description
[0001] The present disclosure relates to subject mater contained in
priority Korean Application No. 10-2005-0062768, filed on Jul. 12,
2005, which is herein expressly incorporated by reference in its
entirety.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] The present invention relates to a cogeneration system, and
more particularly to, a cogeneration system, which improves heating
capacity and efficiency by supplying waste heat of an engine or the
like to a heat pump type air conditioner by a waste heat supplying
heat exchanger, and which operates an engine and a generator
according to operation signals from an air conditioner, thereby
minimizing the flow path between the heat pump type air conditioner
and the waste heat supplying heat exchanger, and reducing
installation costs and flow resistance.
[0004] 2. Description of the Background Art
[0005] In general, a cogeneration system is a system that can
produce both electricity and heat from a single energy source.
[0006] FIG. 1 is a block diagram schematically showing a
cogeneration system in accordance with the prior art.
[0007] The cogeneration system in accordance with the prior art
includes, as shown in FIG. 1, a generator 2 which generates
electric power, a drive source 10 which operates to drive the
generator 2, and generates heat, such as an engine (hereinafter,
the drive source 10 will be referred to as an "engine"), a waste
heat recoverer 20 which recovers waste heat generated from the
engine 10, and a heat consumer 30 which utilizes the waste heat
recovered by the waste heat recoverer 20, such as a thermal storage
tank.
[0008] The electric power generated from the generator 2 is
supplied to various electric home appliances including a heat pump
type air conditioner 4 and various home illumination devices.
[0009] The generator 2 and engine 10 are installed in an engine
room (E) which is defined separately from the heat consumer 30.
[0010] The heat pump type air conditioner 4 includes compressors 5,
a 4-way valve 6, indoor heat exchangers 7, expansion devices 8, and
outdoor heat exchangers 9.
[0011] When the heat pump type air conditioner 4 operates in
cooling mode, each compressor 5 compresses a refrigerant introduced
thereinto. The compressed refrigerant passes through the 4-way
valve 6, outdoor heat exchangers 9, expansion devices 8, and indoor
heat exchangers 7, in this order, and returns to the compressors 5
through the 4-way valve 6. In this case, each outdoor heat
exchanger 9 functions as a condenser, and each indoor heat
exchanger 7 functions as an evaporator to absorb heat from indoor
air.
[0012] On the other hand, when the heat pump type air conditioner 4
operates in heating mode, the refrigerant compressed in each
compressor 5 passes through the 4-way valve 6, indoor heat
exchangers 7, expansion devices 8, and outdoor heat exchangers 9,
in this order, and returns to the compressors 9 through the 4-way
valve 6. In this case, each outdoor heat exchanger 9 functions as
an evaporator, and each indoor heat exchanger 7 functions as a
condenser to heat indoor air.
[0013] The waste heat recoverer 20 includes an exhaust gas heat
exchanger 22 which absorbs heat from exhaust gas discharged from
the engine 10, and a cooling water heat exchanger 24 which absorbs
heat from cooling water used to cool the engine 10.
[0014] The exhaust gas heat exchanger 22 is connected to the heat
consumer 30 via a first heat supply line 23. Accordingly, the
exhaust gas heat exchanger 22 can transfer the waste heat absorbed
from the exhaust gas of the engine 10 to the heat consumer 30 via
the first heat supply line 23
[0015] The cooling water heat exchanger 24 is connected to the heat
consumer 30 via a second heat supply line 25. Accordingly, the
cooling water heat exchanger 24 can transfer the waste heat
absorbed from the cooling water of the engine 10 to the heat
consumer 30 via the second heat supply line 25.
[0016] However, the conventional cogeneration system has a problem
in that the waste heat recovered by the exhaust gas heat exchanger
22 and the cooling water heat exchanger 24 is only used for hot
water supply, warm water or the like in the heat consumer 30, so
that the efficiency of the cogeneration system cannot be
maximized.
SUMMARY OF THE INVENTION
[0017] The present invention has been made in an effort to solve
the above prior art problem, and provide a cogeneration system
capable of maximizing the efficiency thereof by utilizing waste
heat of an engine or the like in a heat pump type air conditioner
by a waste heat supplying heat exchanger, and minimizing a flow
path for guiding a refrigerant to the waste heat supplying heat
exchanger.
[0018] To achieve these and other advantages and in accordance with
the purpose of the present invention, as embodied and broadly
described herein, there is provided a cogeneration system,
including: a generator; a drive source which operates to drive the
generator, and generates heat; a waste heat recovery unit which
recovers the waste heat of the driving source; a heat pump type air
conditioner which is supplied with electric power from the
generator, and includes an indoor unit and outdoor unit; a waste
heat supplying heat exchanger which supplies the heat recovered by
the waste heat recovery unit to the heat pump type air conditioner;
and a waste heat supplying heat exchanger connecting conduit
adapted to guide a refrigerant emerging from the indoor unit during
a heating operation of the heat pump type air conditioner to enter
the outdoor unit through the waste heat supplying heat
exchanger.
[0019] The waste heat supplying connecting conduit includes an
indoor unit connecting conduit which connects the waste heat
supplying heat exchanger and the indoor unit and an outdoor unit
connecting conduit which connects the waste heat supplying heat
exchanger and the outdoor unit.
[0020] A first bypass conduit is formed at the waste heat supplying
heat exchanger connecting conduit to guide the refrigerant emerging
from the outdoor unit during a cooling operation of the heat pump
type air conditioner to bypass the waste heat supplying heat
exchanger.
[0021] A first non-return valve is arranged at the first bypass to
prevent reverse flow of the refrigerant emerging from the indoor
unit during the heating operation of the heat pump type air
conditioner to the first bypass conduit.
[0022] An expansion valve is arranged at the waste heat supplying
heat exchanger connecting conduit to expand the refrigerant
introduced into the waste heat supplying heat exchanger during the
heating operation of the heat pump type air conditioner.
[0023] A second bypass conduit is formed at the waste heat
supplying heat exchanger connecting conduit to bypass the expansion
valve according to an outdoor temperature, and a first heating
valve is arranged at the second bypass conduit has to open and
close the second bypass conduit.
[0024] A second non-return valve is arranged at the waste heat
supplying heat exchanger connecting conduit to prevent reverse flow
of the refrigerant emerging from the outdoor heat exchanger during
the heating operation of the heat pump type air conditioner to the
waste heat supplying heat exchanger.
[0025] The outdoor unit has an outdoor heat exchanger connecting
conduit for connecting the outdoor unit connecting conduit and the
outdoor heat exchanger and a compressor connecting conduit for
connecting the outdoor unit connecting conduit and a suction side
of the compressor in the outdoor unit.
[0026] A second heating valve is arranged at the compressor
connecting conduit to open the compressor connecting conduit when
the heat pump type air conditioner is in a heating mode and the
outdoor temperature is lower than a set temperature.
[0027] The outdoor heat exchanger connecting conduit consists of a
cooling path adapted to guide the refrigerant passed through the
outdoor heat exchanger during a cooling operation of the heat pump
type air conditioner to flow therethough, and a heating path
adapted to guide the refrigerant passed through the waste heat
supplying heat exchanger to enter the outdoor heat exchanger when
the heat pump type IS air conditioner is in a heating mode and the
outdoor temperature is higher than a set temperature.
[0028] A cooling valve is arranged at cooling path to open the
cooling path during the cooling operation of the heat pump type air
conditioner.
[0029] An outdoor expansion valve is arranged at the heating path
to expand the refrigerant passing through the heating path.
[0030] The thus-constructed cogeneration system in accordance with
the invention is constructed such that the waste heat recovered
from the engine is supplied to the heat pump type air conditioner
through the waste heat supplying heat exchanger, thereby maximizing
heating capacity and efficiency.
[0031] Additionally, the waste heat supplying heat exchanger
connecting conduit is formed so as to guide the refrigerant
emerging from the indoor unit to enter the outdoor unit through the
waste heat supplying heat exchanger, so that the flow path between
the waste heat supplying heat exchanger and the heat pump type air
conditioner is minimized, thereby reducing installation costs and
flow resistance.
[0032] Additionally, it is advantageous in that it is easy to
connect the waste heat supplying heat exchanger even when
installing additional indoor and outdoor units.
[0033] Additionally, it is advantageous in that it is possible to
provide a constant heating capacity irrespective of outdoor
temperature and prevent frost formation on the outdoor heat
exchanger because the refrigerant is evaporated by the waste heat
supplying heat exchanger when the heat pump type air conditioner
operates in the heating mode and the outdoor temperature is lower
than a set temperature.
[0034] Additionally, it is advantageous in that it is possible to
operate the heat pump type air conditioner only by an external
power source because the outdoor heat exchanger alone can be used
as an evaporator when the heat pump type air conditioner operates
in the heating mode and the outdoor temperature is higher than a
set temperature.
[0035] Additionally, it is advantageous in that both the waste heat
supplying heat exchanger and the outdoor heat exchanger can be used
as an evaporator.
BRIEF DESCRIPTION OF THE DRAWINGS
[0036] In the drawings:
[0037] FIG. 1 is a schematic view of a cogeneration system in
accordance with the prior art;
[0038] FIG. 2 is a schematic view of a cogeneration system in
accordance with the present invention when a heat pump type air
conditioner operates in a cooling mode;
[0039] FIG. 3 is a schematic view of the cogeneration system in
accordance with the present invention when the heat pump type air
conditioner operates in a cooling mode and the outdoor temperature
is lower than a set temperature; and
[0040] FIG. 4 is a schematic view of the cogeneration system in
accordance with the present invention when the heat pump type air
conditioner operates in the heating mode and the outdoor
temperature is higher than a set temperature.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0041] Hereinafter, an exemplary embodiment of a cogeneration
system in accordance with the invention will be described with
reference to the accompanying drawings.
[0042] There may be a plurality of exemplary embodiments of the
cogeneration system and the method for controlling the same in
accordance with the invention, but the most preferred embodiment
will be described hereinafter.
[0043] FIG. 2 is a schematic view of a cogeneration system in
accordance with the present invention when a heat pump type air
conditioner operates in a cooling mode. FIG. 3 is a schematic view
of the cogeneration system in accordance with the present invention
when the heat pump type air conditioner operates in a cooling mode
and the outdoor temperature is lower than a set temperature. FIG. 4
is a schematic view of the cogeneration system in accordance with
the present invention when the heat pump type air conditioner
operates in the heating mode and the outdoor temperature is higher
than a set temperature.
[0044] The cogeneration system in accordance with the embodiment of
the present invention includes, as shown in FIGS. 2 to 4, a
generator 50, a drive source which operates to drive the generator
50, and generates heat, a waste heat recovery unit 60 which
recovers the waste heat of the driving source, a heat pump type air
conditioner 1000 which is supplied with electric power from the
generator 50, and includes an indoor unit 101 and outdoor unit 102,
a waste heat supplying heat exchanger 70 which supplies the heat
recovered by the waste heat recovery unit 60 to the heat pump type
air conditioner 100, and a waste heat supplying heat exchanger
connecting conduit 80 adapted to guide a refrigerant emerging from
the indoor unit 101 during a heating operation of the heat pump
type air conditioner 100 to enter the outdoor unit 102 through the
waste heat supplying heat exchanger 70.
[0045] The generator 50 may be an AC generator or a DC generator.
The generator 50 includes a rotor coupled to an output shaft of the
drive source so that the generator 50 generates electric power
during rotation of the output shaft.
[0046] The generator 50 is connected via an electrical power line
51 in order to supply the generated electric power.
[0047] The drive source comprises a fuel cell or an engine 52 which
operates using fossil fuel such as gas or petroleum. The following
description will be given only in conjunction with the case in
which the drive source comprises an engine 52.
[0048] A fuel injection port 53 for injecting fuel such as gas or
petroleum and an exhaust tube 54, through which exhaust gas
discharged from the engine 52 passes, are installed at the engine
52.
[0049] The waste heat recovery unit 60 includes a cooling water
heat exchanger 61 connected to the engine 52 via a cooling water
line 64 to recover heat of cooling water of the engine 52, a first
exhaust gas heat exchanger 62 arranged at the exhaust port 54 to
recover heat of exhaust gas discharged from the engine 52, and a
second exhaust gas heat exchanger 63 arranged at the exhaust port
54 to recover the residual heat of the exhaust gas that has passed
through the first exhaust gas heat exchanger 62.
[0050] A cooling water circulation pump 65 is arranged in the
cooling water line 64 to cause cooling water to be circulated.
[0051] The cooling water heat exchanger 61, first exhaust gas heat
exchanger 62, and second exhaust gas heat exchanger 63 are
connected to the waste heat supplying heat exchanger 70 via a heat
transfer unit.
[0052] The heat transfer unit includes a heat medium circulation
conduit 66 to guide the heat medium to be circulated through the
cooling water heat exchanger 61, second exhaust gas heat exchanger
63, first exhaust gas heat exchanger 62, and waste heat supplying
heat exchanger 70.
[0053] A heat medium circulation pump 67 is arranged at the heat
medium circulation conduit 66 to pump the heat medium.
[0054] An expansion tank 68 for containing gas generated as the
heat medium is circulated is arranged at the inlet side of the heat
medium circulation pump 67.
[0055] Meanwhile, the cogeneration system further includes a
radiating heat exchanger 90 adapted to radiate the heat recovered
by the waste heat recovery unit 60 during a cooling operation of
the heat pump type air conditioner 100.
[0056] The radiating heat exchanger 90 is connected to the heat
medium circulation conduit 66 via a radiating bypass conduit 91, so
that the heat medium passing through the heat medium circulation
conduit 66 bypasses the waste heat supplying heat exchanger 70.
[0057] A three-way valve is arranged at a junction of the radiating
bypass conduit 91 and the heat medium circulation conduit 66.
[0058] The description of the cogeneration system in accordance
with the embodiment of the present invention will be given only in
conjunction with the case in which heat of the radiating heat
exchanger is emitted to the air, but the heat may also be used in a
hot water supply tank or thermal storage tank.
[0059] A radiating fan 93 is arranged at the radiating heat
exchanger 90 to blow outdoor air to the radiating heat exchanger
90.
[0060] Meanwhile, the heat pump type air conditioner 100 may be
constructed such that the indoor unit 101 and the outdoor unit 102
are singular or at least one of the indoor unit 101 and the Outdoor
unit 102 is plural. Here, the following description will be given
only in conjunction with the case in which the heat pump air
conditioner includes a plurality of indoor units 101 and a
plurality of outdoor units 102.
[0061] The plurality of indoor units 101 each include an indoor
expansion valve 103 and an indoor heat exchanger 104, and the
plurality of outdoor units 102 each includes a compressor 105, a
four-way valve 106, an outdoor heat exchanger 107, and an outdoor
expansion valve 108.
[0062] The indoor unit 101 and the outdoor unit 102 are
interconnected by a refrigerant circulating path 110.
[0063] Meanwhile, the waste heat supplying heat exchanger
connecting conduit 80 includes an indoor unit connecting conduit 81
which connects the waste heat supplying heat exchanger 70 and the
indoor unit 101 and an outdoor unit connecting conduit 82 which
connects the waste heat supplying heat exchanger 70 and the outdoor
unit 102.
[0064] That is, the waste heat supplying heat exchanger 70 is
connected to the indoor unit 101 and the outdoor unit 102 by each
single flow path, respectively.
[0065] A first bypass conduit is formed between the indoor unit
connecting conduit 81 and the outdoor unit connecting conduit 82 to
guide the refrigerant emerging from the outdoor unit 102 during a
cooling operation of the heat pump type air conditioner 100 to
bypass the waste heat supplying heat exchanger 70 and directly
enter the indoor unit 101.
[0066] A first non-return valve 84 is arranged at the first bypass
conduit 83 to prevent reverse flow of the refrigerant emerging from
the indoor unit 101 during the heating operation of the heat pump
type air conditioner 100 to the first bypass conduit 83.
[0067] An expansion valve 85 is arranged at the indoor unit
connecting conduit 81 to expand the refrigerant introduced into the
waste heat supplying heat exchanger 70 from the indoor unit 101
during the heating operation of the heat pump type air conditioner
100.
[0068] A second bypass conduit 86 is formed at the indoor unit
connecting conduit 81 to bypass the expansion valve 85 according to
an outdoor temperature, and a first heating valve 87 is arranged at
the second bypass conduit 86 to open and close the second bypass
conduit 86.
[0069] A second non-return valve 86 is arranged at the outdoor unit
connecting conduit 82 to prevent reverse flow of the refrigerant
emerging from the outdoor heat exchanger 107 during the heating
operation of the heat pump type air conditioner 100 to the waste
heat supplying heat exchanger 70.
[0070] The outdoor unit 102 has an outdoor heat exchanger
connecting conduit 120 for connecting the outdoor unit connecting
conduit 82 and the outdoor heat exchanger 107 and a compressor
connecting conduit 125 for connecting the outdoor unit connecting
conduit 82 and a suction side of the compressor 105.
[0071] The outdoor heat exchanger connecting conduit 120 consists
of a cooling path 121 adapted to guide the refrigerant passed
through the outdoor heat exchanger 105 during a cooling operation
of the beat pump type air conditioner 100 to flow therethough, and
a heating path 122 adapted to guide the refrigerant passed through
the waste heat supplying heat exchanger 70 to enter the outdoor
heat exchanger 107 when the heat pump type air conditioner 100 is
in a heating mode and the outdoor temperature is higher than a set
temperature.
[0072] A cooling valve 123 is arranged at the cooling path 121 to
open the cooling path 121 during the cooling operation of the heat
pump type air conditioner 100.
[0073] An outdoor expansion valve 108 is arranged at the heating
path has 122 to expand the refrigerant passing through the heating
path 122.
[0074] A second heating valve 126 is arranged at the compressor
connecting conduit 125 to open the compressor connecting conduit
125 when the heat pump type air conditioner 100 is in a heating
mode and the outdoor temperature is lower than a set
temperature.
[0075] Hereinafter, operation of the cogeneration system having the
above-described configuration will be described.
[0076] When the engine 52 is driven, the generator 50 produces
electricity by the driving force of the engine 52. The electricity
produced by the generator 50 is supplied to the heat pump type air
conditioner 100.
[0077] Exhaust gas waste heat and cooling water waste heat from the
engine 52 are recovered by the cooling water heat exchanger 61 and
the first and second exhaust gas heat exchangers 62 and 63,
respectively.
[0078] The heat medium on the heat medium circulation conduit 66 is
pumped by the heat medium circulation pump 67, so that the heat
medium recovers waste heat while passing through the cooling water
heat exchanger 61, second exhaust gas heat exchanger 63, and first
exhaust gas heat exchanger 62.
[0079] Meanwhile, as shown in FIG. 2, during a cooling operation of
the heat pump type air conditioner 100, the three-way valve 92
opens the radiating conduit 91, so that the recovered heat is
emitted to the air via the radiating heat exchanger 90.
[0080] In the outdoor unit 102, the compressor 105 is driven, and
the four-way valve 106 is switched to a heating mode.
[0081] Thus, the refrigerant compressed in the compressor 105
sequentially passes through the four-way valve 106 and the outdoor
heat exchanger 107.
[0082] The cooling valve 123 is turned on to thus open the cooling
path 121, so that the refrigerant that has passed through the
outdoor heat exchanger 107 escapes from the outdoor unit 102
through the cooling path 121.
[0083] At this time, the outdoor expansion valve 108 and the second
heating valve 126 are turned off, to thus shield the compressor
connecting conduit 125 and the heating path 122.
[0084] The refrigerant emerging from the outdoor unit 102 is
introduced into the outdoor unit connecting conduit 82, then flowed
to the indoor unit connecting conduit 81 via the first bypass
conduit 83, and then introduced into the indoor unit 101.
[0085] At this time, the first heating valve 87 and the expansion
valve 85 are turned off, respectively, to prevent the refrigerant
from being introduced into the waste heat supplying heat exchanger
70.
[0086] The refrigerant introduced into the indoor unit 101 passes
through the indoor expansion valve 103 and the indoor heat
exchanger 104, and then is re-circulated into the outdoor unit 102
via the refrigerant circulating path 110.
[0087] On the other hand, as shown in FIG. 3, when the heat pump
type air conditioner 100 operates in a heating mode, and the
outdoor temperature is lower than a set temperature, the outdoor
heat exchanger 107 is not used but the waste heat supplying heat
exchanger 70 alone is used as an evaporator.
[0088] First, the three-way valve 92 opens the heat medium
circulation conduit 66 so as to guide the heat medium to the waste
heat supplying heat exchanger 70.
[0089] The heat medium on the heat medium circulation conduit 66 is
pumped by the heat medium circulation pump 67, so that the heat
medium recovers waste heat while passing through the cooling water
heat exchanger 61, second exhaust gas heat exchanger 63, and first
exhaust gas heat exchanger 62, and thereafter the recovered waste
heat is transferred to the waste heat supplying heat exchanger
70.
[0090] In the outdoor unit 102, the compressor 105 is driven, and
the four-way valve 106 is switched to a heating mode.
[0091] The refrigerant compressed in the compressor 105 passes
through the four-way vale 104 and the indoor expansion valve 103,
and then is introduced into the waste heat supplying heat exchanger
via the indoor unit connecting conduit 81.
[0092] At this time, the expansion valve 85 is turned on, and the
first heating valve 72 is turned off, to thus shield the second
bypass conduit 86.
[0093] Thus, the refrigerant emerging from the indoor unit 101 does
not pass through the second bypass conduit 86 but passes through
the expansion valve 85.
[0094] The refrigerant expanded in the expansion valve 85 is
supplied with heat while passing through the waste heat supplying
heat exchanger 70, and thereafter introduced into the outdoor unit
102 via the outdoor unit connecting conduit 82.
[0095] In the outdoor unit 102, the second heating valve 126 is
turned on to thus open the compressor connecting conduit 125, and
the cooling valve 123 and the outdoor expansion valve 108 are
turned off, to thus shield the cooling path 121 and the heating
path 122, respectively.
[0096] Thus, the refrigerant introduced into the outdoor unit 102
is not introduced into the outdoor heat exchanger 70, but
circulated into the compressor 105 via the compressor connecting
conduit 125.
[0097] That is, when the outdoor temperature is lower than a set
temperature, the outdoor heat exchanger 107 is not used, and the
waste heat supplying heat exchanger 70 alone is used.
[0098] Accordingly, it is possible to provide a constant heating
capacity irrespective of outdoor temperature, and prevent the
outdoor heat exchanger 107 from being frosted.
[0099] Meanwhile, as shown in FIG. 4, when the heat pump type air
conditioner 100 is in a heating mode, and the outdoor temperature
is higher than a set temperature, the outdoor heat exchanger 107
alone is used as an evaporator.
[0100] That is, the engine 52 is not driven, and accordingly the
heat pump type air conditioner 100 is supplied with only commercial
electric power from an external power source.
[0101] Thus, the refrigerant compressed in the compressor 105
escapes from the outdoor unit 102 via the four-way valve 106, and
then is introduced into the indoor unit 101.
[0102] The refrigerant introduced into the indoor unit 101 passes
through the indoor heat exchanger 104 and the indoor expansion
valve 103, and then passes through the waste heat supplying heat
exchanger 70 via the indoor unit connecting conduit 81.
[0103] At this time, the first heating valve 87 is turned on, to
thus open the second bypass conduit 86, and the expansion valve 85
is turned off.
[0104] Thus, the refrigerant does not pass through the expansion
valve 85, but passes through the waste heat supplying heat
exchanger 70 via the second bypass conduit 86.
[0105] Here, because the engine 52 is not driven, the waste heat
supplying heat exchanger 70 is unable to be supplied with waste
heat of the engine 52, so that the waste heat supplying heat
exchanger 70 does not functions as an evaporator.
[0106] The refrigerant that has passed through the waste heat
supplying heat exchanger 70 is introduced into the outdoor unit
102.
[0107] At this time, the outdoor expansion valve is turned on, to
thus open the heating path 122, and the second heating valve 126
and the cooling valve 123 are turned off, to thus shield the
compressor connecting conduit 125 and the cooling path 121,
respectively.
[0108] Thus, the refrigerant introduced into the outdoor unit 102
is introduced into the heating path 122 and expanded in the outdoor
expansion valve 108, and thereafter evaporated in the outdoor heat
exchanger 107.
[0109] The refrigerant evaporated in the outdoor heat exchanger 107
is circulated into the compressor 105.
[0110] Accordingly, when the heat pump type air conditioner 100 is
in a heating mode, and the outdoor temperature is higher than a set
temperature, the outdoor heat exchanger 107 alone functions as an
evaporator, thereby making it possible to operate the heat pump
type air conditioner 100 by an external power source when a failure
occurs in the engine 52 or the generator 50.
[0111] The effects of the thus-constructed cogeneration system in
accordance with the present invention will be described below.
[0112] The thus-constructed cogeneration system in accordance with
the invention is constructed such that the waste heat recovered
from the engine is supplied to the heat pump type air conditioner
through the waste heat supplying heat exchanger, thereby maximizing
heating capacity and efficiency.
[0113] Additionally, the waste heat supplying heat exchanger is
connected to the indoor unit and the outdoor unit by each single
flow path, respectively, so that the flow path between the waste
heat supplying heat exchanger and the heat pump type air
conditioner is minimized, thereby reducing installation costs and
flow resistance.
[0114] Additionally, it is advantageous in that it is easy to
connect the waste heat supplying heat exchanger even when
installing additional indoor and outdoor units.
[0115] Additionally, it is advantageous in that it is possible to
provide a constant heating capacity irrespective of outdoor
temperature and prevent frost formation on the outdoor heat
exchanger because the refrigerant is evaporated by the waste heat
supplying heat exchanger when the heat pump type air conditioner
operates in the heating mode and the outdoor temperature is lower
than a set temperature.
[0116] Additionally, it is advantageous in that it is possible to
operate the heat pump type air conditioner only by an external
power source because the outdoor heat exchanger alone can be used
as an evaporator when the heat pump type air conditioner operates
in the heating mode and the outdoor temperature is higher than a
set temperature.
[0117] Additionally, it is advantageous in that both the waste heat
supplying heat exchanger and the outdoor heat exchanger can be used
as an evaporator.
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