U.S. patent application number 11/456655 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 | 20070012418 11/456655 |
Document ID | / |
Family ID | 37023033 |
Filed Date | 2007-01-18 |
United States Patent
Application |
20070012418 |
Kind Code |
A1 |
CHO; Eun Jun ; et
al. |
January 18, 2007 |
COGENERATION SYSTEM
Abstract
A cogeneration system has an advantage that a cogeneration
section is divided into a main unit and a sub unit, and an engine
and a generator are included in the main unit, to thus enable the
main unit and the sub unit to be installed at different locations,
so that the main unit can be installed on the ground floor or
basement of a building to thus minimize building vibrations or
noises generated by a load, and the sub unit can be installed near
to an air conditioner to thus minimize the length of a refrigerant
passage, thereby reducing the installation cost and the flow
passage 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: |
37023033 |
Appl. No.: |
11/456655 |
Filed: |
July 11, 2006 |
Current U.S.
Class: |
165/58 ;
62/531 |
Current CPC
Class: |
F25B 2313/02743
20130101; F25B 2313/02523 20130101; F25B 2313/006 20130101; F25B
2500/13 20130101; Y02P 80/15 20151101; F25B 13/00 20130101; Y02A
30/274 20180101; Y02E 20/14 20130101; F25B 2313/023 20130101; F25B
27/02 20130101; Y02P 80/152 20151101 |
Class at
Publication: |
165/058 ;
062/531 |
International
Class: |
F25B 29/00 20060101
F25B029/00; F25C 1/24 20060101 F25C001/24 |
Foreign Application Data
Date |
Code |
Application Number |
Jul 12, 2005 |
KR |
10-2005-0062770 |
Claims
1. A cogeneration system, comprising: an air conditioner having an
indoor unit and an outdoor unit; a main unit including a driving
source for generating heat and a waste heat recovery device for
recovering waste heat of the driving source; and a sub unit
installed between the air conditioner and the main unit, and
including a waste heat supplying heat exchanger for supplying the
heat recovered by the waste heat recovery device to the air
conditioner.
2. The cogeneration system of claim 1, wherein the main unit and
the sub unit are connected by a heat medium passage through which a
heat medium transferring heat to the waste heat supplying heat
exchanger from the waste heat recovery device can circulate.
3. The cogeneration system of claim 2, wherein the heat medium
passage includes a main unit heat medium passage installed so as to
pass through the waste heat recovery device within the main unit, a
sub unit heat medium passage installed so as to pass through the
waste heat supplying heat exchanger within the sub unit, and a unit
connecting passage connecting the main unit heat medium passage and
the sub unit heat medium passage.
4. The cogeneration system of claim 1, wherein the sub unit and the
air conditioner are connected by a refrigerant passage through
which a refrigerant transferring heat to the outdoor unit from the
waste heat supplying heat exchanger can circulate.
5. The cogeneration system of claim 4, wherein the refrigerant
passage includes a sub unit refrigerant passage installed so as to
pass through the waste heat supplying heat exchanger within the sub
unit, an air conditioner refrigerant passage installed so that the
refrigerant can circulate through the air conditioner, and an air
conditioner connecting passage connecting the sub unit refrigerant
passage and the air conditioner refrigerant passage.
6. The cogeneration system of claim 5, wherein the sub unit
refrigerant passage has a bypass passage for allowing the
refrigerant to bypass the waste heat supplying heat exchanger
during the cooling operation of the air conditioner.
7. The cogeneration system of claim 6, wherein the bypass passage
has a first check valve for preventing reverse flow of the
refrigerant.
8. The cogeneration system of claim 5, wherein the sub unit
refrigerant passage has a second check valve for preventing reverse
flow of the refrigerant that has passed through the waste heat
supplying heat exchanger.
9. The cogeneration system of claim 5, wherein the sub unit
refrigerant passage has an on-off valve for preventing the
refrigerant from being introduced into the waste heat supplying
heat exchanger during the cooling operation of the air
conditioner.
10. The cogeneration system of claim 5, wherein the air conditioner
connecting passage is connected between the sub unit and the
outdoor unit of the air conditioner.
11. The cogeneration system of claim 1, wherein the sub unit has a
radiator for radiating the heat recovered by the waste heat
recovery device.
12. The cogeneration system of claim 11, wherein the heat radiator
is a radiation heat exchanger connected to the inlet side of the
waste heat supplying heat exchanger by a radiation passage.
13. The cogeneration system of claim 1, wherein the main unit
further includes a main unit controller for controlling the
engine.
14. The cogeneration system of claim 13, wherein the main unit
further comprises a main unit temperature sensor which senses a
temperature of the heat medium circulating through the waste heat
recovery device and transmits a sensing signal to the main unit
controller.
15. The cogeneration system of claim 1, wherein the sub unit
further includes a sub unit controller for controlling the passages
of the heat medium and the refrigerant circulating in the sub
unit.
16. The cogeneration system of claim 15, wherein the sub unit
further comprises a main unit temperature sensor which senses a
temperature of the refrigerant circulating through the waste heat
recovery device and transmits a sensing signal to the sub unit
controller.
17. A cogeneration system, comprising: an air conditioner having an
indoor unit and an outdoor unit; a main unit including a driving
source for generating heat and a waste heat recovery device for
recovering waste heat of the driving source; and a sub unit
installed between the air conditioner and the main unit, and
including a waste heat supplying heat exchanger for supplying the
heat recovered by the waste heat recovery device to the air
conditioner and a radiator for radiating the heat recovered by the
waste heat recovery device.
18. The cogeneration system of claim 17, wherein the main unit and
the sub unit are connected by a heat medium passage through which a
heat medium transferring heat to the waste heat supplying heat
exchanger from the waste heat recovery device can circulate.
19. The cogeneration system of claim 18, wherein the sub unit and
the air conditioner are connected by a refrigerant passage through
which a refrigerant transferring heat to the outdoor unit from the
waste heat supplying heat exchanger can circulate.
20. The cogeneration system of claim 19, wherein the main unit
further includes a main unit controller for controlling the engine,
and the sub unit further includes a sub unit controller for
controlling the passages of the heat medium and the refrigerant
circulating in the sub unit.
Description
[0001] The present disclosure relates to subject matter contained
in priority Korean Application No. 10-2005-0062770, 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, in which a
cogeneration section includes a main unit and a sub unit, so that
the sub unit can be installed near to an air conditioner to thus
lessen the length of a refrigerant passage connecting the sub unit
and the air conditioner, thereby reducing the installation cost and
the flow passage 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 cogeneration section 20 comprised
of a generator 1 for producing electricity, an engine 4 for driving
the generator 1, a waste heat recovery unit 10 for recovering waste
beat generated by the engine 4, and a heat demand site 6, such as a
heat storage tank, where the waste heat of the waste heat recovery
unit 10 is used, and a heat pump type air conditioner 30 driven by
the electricity produced by the generator 2.
[0008] The generator 2 and the heat pump type air conditioner 30
are connected to a power line 8 for supplying electricity.
[0009] The waste heat recovery unit 10 includes an exhaust gas heat
exchanger 12 for removing heat from exhaust gas discharged from the
engine 4 and a cooling water heat exchanger 14 for removing heat
from cooling water that has cooled the engine 4.
[0010] The heat pump type air conditioner 30 includes a compressor
31, a four-way valve 32, an indoor heat exchanger 33, an expansion
valve 34, and an outdoor heat exchanger 35.
[0011] In the cogeneration system thus constructed, when the engine
4 is operated, the generator 2 produces electricity by the driving
force of the engine 4.
[0012] The electricity produced by the generator 2 is supplied to
the air conditioner 30 via the power line 8, to thus operate the
air conditioner 30.
[0013] The waste heat generated by the engine 4 is recovered by the
waste heat recovery equipment 8, and used in the heat demanding
site 10.
[0014] When the engine 4 is stopped, the generator 2 is also
stopped, to thus stop the power supply to the air conditioner 30
from the generator 2.
[0015] However, the cogeneration system in accordance with the
prior art has a problem in that only the electricity produced by
the generator 2 is supplied to the air conditioner 30, and the
waste heat recovered by the engine 4 is only utilized for hot water
supply, warm water, or the like in the heat demanding site, so that
it is impossible to maximize the efficiency of the system. Besides,
there is a problem that the weight of the cogeneration section 20
is so large that there are restrictions on installation
locations.
SUMMARY OF THE INVENTION
[0016] The present invention has been made in an effort to solve
the above prior art problem, and provide a cogeneration system,
which is constructed such that both electricity and waste heat of a
cogeneration section can be utilized in a heat pump type air
conditioner, and restrictions on installation locations of the
cogeneration section can be overcome, thereby improving the system
efficiency.
[0017] 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: an air conditioner having an indoor unit and an outdoor
unit; a main unit including a driving source for generating heat
and a waste heat recovery device for recovering waste heat of the
driving source; and a sub unit installed between the air
conditioner and the main unit, and including a waste heat supplying
heat exchanger for supplying the heat recovered by the waste heat
recovery device to the air conditioner.
[0018] The main unit and the sub unit are connected by a heat
medium passage through which a heat medium transferring heat to the
waste heat supplying heat exchanger from the waste heat recovery
device can circulate.
[0019] The heat medium passage includes a main unit heat medium
passage installed so as to pass through the waste heat recovery
device within the main unit, a sub unit heat medium passage
installed so as to pass through the waste heat supplying heat
exchanger within the sub unit, and a unit connecting passage
connecting the main unit heat medium passage and the sub unit heat
medium passage.
[0020] The sub unit and the air conditioner are connected by a
refrigerant passage through which a refrigerant transferring heat
to is the outdoor unit from the waste heat supplying heat exchanger
can circulate.
[0021] The refrigerant passage includes a sub unit refrigerant
passage installed so as to pass through the waste heat supplying
heat exchanger within the sub unit, an air conditioner refrigerant
passage installed so that the refrigerant can circulate through the
air conditioner, and an air conditioner connecting passage
connecting the sub unit refrigerant passage and the air conditioner
refrigerant passage.
[0022] The sub unit refrigerant passage has a bypass passage for
allowing the refrigerant to bypass the waste heat supplying heat
exchanger during the cooling operation of the air conditioner, and
the bypass passage has a first check valve for preventing reverse
flow of the refrigerant.
[0023] The sub unit refrigerant passage has a second check valve
for preventing reverse flow of the refrigerant that has passed
through the waste heat supplying heat exchanger.
[0024] The sub unit refrigerant passage has an on-off valve for
preventing the refrigerant from being introduced into the waste
heat supplying heat exchanger during the cooling operation of the
air conditioner.
[0025] The sub unit has a radiator for radiating the heat recovered
by the waste heat recovery device.
[0026] The main unit further includes a main unit controller for
controlling the engine, and the sub unit further includes a sub
unit controller for controlling the passages of the heat medium and
the refrigerant circulating in the sub unit.
[0027] The cogeneration system in accordance with the invention has
an advantage that a cogeneration section is divided into a main
unit and a sub unit, and an engine and a generator are included in
the main unit, to thus enable the main unit and the sub unit to be
installed at different locations, so that the main unit can be
installed on the ground floor or basement of a building to thus
minimize building vibrations or noises generated by a load, and the
sub unit can be installed near to an air conditioner to thus
minimize the length of a refrigerant passage, thereby reducing the
installation cost and the flow passage resistance.
[0028] Additionally, the sub unit can be installed on the roof, so
that the radiation effect of a radiator installed on the sub unit
can be enhanced.
[0029] Additionally, the waste heat recovered from the engine is
supplied to the air conditioner through the waste heat supplying,
heat exchanger, so that the heating performance and efficiency can
be maximized.
[0030] Additionally, in the case that the air conditioner is in a
heating operation and the outdoor temperature is lower than a set
temperature, the refrigerant is evaporated by the waste heat
supplying heat exchanger, so that a constant heating performance
can be obtained regardless of the outdoor temperature, and frost
formation on an outdoor heat exchanger can be prevented.
BRIEF DESCRIPTION OF THE DRAWINGS
[0031] In the drawings:
[0032] FIG. 1 is a block diagram schematically showing a
cogeneration system in accordance with the prior art;
[0033] FIG. 2a is a schematic view showing a cogeneration section
when a cogeneration system in accordance with the present invention
is in a cooling operation;
[0034] FIG. 2b is a schematic view showing an air conditioner when
the cogeneration system in accordance with the present invention is
in the cooling operation;
[0035] FIG. 3 is a schematic view showing when the cogeneration
system in accordance with the present invention is in a heating
operation and the outdoor temperature is lower than a set
temperature; and
[0036] FIG. 4 is a schematic view showing when the cogeneration
system in accordance with the present invention is in the heating
operation and the outdoor temperature is higher than a set
temperature.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0037] Hereinafter, an exemplary embodiment of a cogeneration
system in accordance with the invention will be described with
reference to the accompanying drawings.
[0038] There may be a plurality of exemplary embodiments of the
cogeneration system in accordance with the invention, but the most
preferred embodiment will be described hereinafter.
[0039] FIG. 2a is a schematic view showing a cogeneration section
when a cogeneration system in accordance with the present invention
is in a cooling operation. FIG. 21b is a schematic view showing an
air conditioner when the cogeneration system in accordance with the
present invention is in the cooling operation. FIG. 3 is a
schematic view showing when the cogeneration system in accordance
with the present invention is in a heating operation and the
outdoor temperature is lower than a set temperature. FIG. 4 is a
schematic view showing when the cogeneration system in accordance
with the present invention is in the heating operation and the
outdoor temperature is higher than a set temperature.
[0040] The cogeneration system in accordance with an exemplary
embodiment of the invention includes a cogeneration section 50 for
producing electricity and heat and an air conditioner 100 operated
by the produced electricity and heat supplied from the cogeneration
section 50.
[0041] The cogeneration section 50 includes a main unit 60
installed on the basement or ground floor of a building and a sub
unit 80 installed near the air conditioner 100, separately from the
main unit 60.
[0042] The air conditioner 100 includes an indoor unit 110 and an
outdoor unit 120, The description of the outdoor unit 120 and the
sub unit 80 is limited to an explanation of those installed on the
roof of a building.
[0043] The main unit 60 includes a generator 61 for producing
electricity, a driving source for driving the generator 61 and
generating heat, and a waste heat recovery device 63 for recovering
waste heat of the driving source.
[0044] The sub unit 80 includes a waste heat supplying heat
exchanger 81 for supplying the heat recovered by the waste heat
recovery device 63 to the air conditioner 100 and a radiator for
radiating heat the recovered by the waste heat recovery device
63.
[0045] The sub unit 80 is installed between the air conditioner 100
and the main unit 60.
[0046] The generator 61 is either an AC generator or a DC
generator, the rotor of which is connected to an output shaft of
the driving source to produce electricity when the Output shaft
rotates.
[0047] The driving source may comprise a fuel cell, or an engine 62
operated using fossil fuels, such as gas or oil, and the
description thereof is limited to an explanation of the engine
62.
[0048] The engine 62 has a fuel injection port 67 through which
fuels, such as gas or oil, pass and an exhaust port 68 through
which exhaust gas discharged from the engine 62 passes.
[0049] The waste heat recovery device 63 includes a cooling water
heat exchanger 64 connected to the engine 62 through a cooling
water passage 69, for recovering the heat of the cooling water of
the engine 62, a first exhaust gas heat exchanger 65 installed on
the exhaust port 68 so as to recover the exhaust gas heat
discharged from the engine 62, and a second exhaust gas heat
exchanger 66 for recovering remaining waste heat of the exhaust gas
from which waste heat has been removed in the first exhaust gas
heat exchanger 65.
[0050] The cooling water passage 69 has a cooling water circulation
pump 70 for circulating cooling water.
[0051] The main unit 60 has a ventilation fan 71 for blowing
outdoor air into the main unit 60 and a motor 72 for driving the
ventilation fan 71.
[0052] The main unit 60 and the sub unit 80 are connected by a heat
medium passage 51 through which a heat medium transferring heat to
the waste heat supplying heat exchanger 81 from the waste heat
recovery device 63 can circulate.
[0053] The heat medium passage 51 includes a main unit heat medium
passage 52 installed so as to pass through the waste heat recovery
device 63 within the main unit 60, a sub unit heat medium passage
53 installed so as to pass through the waste heat supplying heat
exchanger 81 within the sub unit 80, and a unit connecting passage
54 connecting the main unit heat medium passage 52 and the sub unit
heat medium passage 53.
[0054] The main unit heat medium passage 52 connects the cooling
heat exchanger 64, the second exhaust gas heat exchanger 66, and
the first exhaust gas heat exchanger 65.
[0055] On the sub unit heat medium passage 53, the radiator is
connected to the inlet side of the waste heat supplying heat
exchanger 81 by a radiation passage 83.
[0056] A three-way valve 84 is installed at the connecting portion
of the sub unit heat medium passage 53 and the radiation passage
83.
[0057] The radiator is a radiation heat exchanger 82 which radiates
the heat recovered by the waste heat recovery device 63 to the
outside, and the radiation heat exchanger 82 has a radiation fan 85
for blowing outdoor air to the radiation heat exchanger.
[0058] To the sub unit 80, installed are a heat medium circulation
pump 55 for circulating the heat medium of the sub unit heat medium
passage 53 and an expansion tank 86 for containing gas generated
from the sub unit heat medium passage 53,
[0059] The expansion tank 86 is installed at the inlet side of the
heat medium circulation pump 55.
[0060] The sub unit 80 and the air conditioner 100 are connected by
a refrigerant passage 101 through which a refrigerant transferring
heat to the outdoor unit 120 from the waste heat supplying heat
exchanger 81 can circulate.
[0061] The refrigerant passage 101 includes a sub unit refrigerant
passage 102 installed so as to pass through the waste heat
supplying heat exchanger 81 within the sub unit 80, an air
conditioner refrigerant passage 103 installed so that the
refrigerant can circulate through the air conditioner 100, and an
air conditioner connecting passage 104 connecting the sub unit
refrigerant passage 102 and the air conditioner refrigerant passage
103.
[0062] The sub unit refrigerant passage 102 has a bypass passage 87
for allowing the refrigerant to bypass the waste heat supplying
heat exchanger 81 during the cooling operation of the air
conditioner 100.
[0063] The bypass passage 87 has a first check valve 88 for
preventing reverse flow of the refrigerant.
[0064] The sub unit refrigerant passage 102 has a second check
valve 89 for preventing reverse flow of the refrigerant that has
passed through the waste heat supplying heat exchanger 82.
[0065] The second check valve 89 is installed at the outlet side of
the waste heat supplying heat exchanger 81.
[0066] The sub unit refrigerant passage 102 has an on-off valve 90
for preventing the refrigerant from being introduced into the waste
heat supplying heat exchanger 81 during the cooling operation of
the air conditioner 100.
[0067] The on-off valve 90 is installed at the inlet side of the
waste heat supplying heat exchanger 81.
[0068] The main unit 60 further includes a main unit controller 73
for controlling the engine 62. The sub unit 80 further includes a
sub unit controller 91 for controlling the passages of the heat
medium and the refrigerant circulating in the sub unit 80.
[0069] It is preferred that the main unit controller 73 and the sub
unit controller 91 are connected for enabling communication
therebetween.
[0070] The main unit 60 further includes a main unit temperature
sensor 74, which senses a temperature of the heat medium
circulating through the waste heat recovery device 63 and transmits
a sensing signal to the main unit controller 73. The sub unit 80
further includes a main unit temperature sensor which senses a
temperature of the refrigerant circulating through the waste heat
recovery device 63 and transmits a sensing signal to the sub unit
controller 91.
[0071] The air conditioner 100 is a heat pump type air conditioner.
The outdoor unit 120 includes a compressor 121, a four-way valve
122, an outdoor heat exchanger 123, and an outdoor expansion device
124, and the indoor unit 110 includes an indoor heat exchanger 111
and an indoor expansion device 112.
[0072] The outdoor unit 120 and the indoor unit 110 may be either
singular or plural, and the description thereof will be made with
respect to a case where they are in plural.
[0073] Within the outdoor unit 120, an outdoor heat exchanger
bypass passage 125 is installed for allowing the refrigerant passed
through the indoor unit 110 to bypass the outdoor heat exchanger
123 during a heating operation of the air conditioner 100.
[0074] On the outdoor heat exchanger bypass passage 125, a first
heating on-off valve 126 opened during the heating operation of the
air conditioner 100 and the outdoors expansion device 124 are
installed.
[0075] On the air conditioner connecting passage 104, a cooling
on-off valve 127, which is opened so as to supply the refrigerant
to the outdoor heat exchanger 123 during the cooling operation of
the air conditioner 100, is installed.
[0076] A third check valve 128 is installed between the outlet side
of the outdoor heat exchanger 123 and the air conditioner
refrigerant passage 103 so as to prevent reverse flow of the
refrigerant passed through the outdoor heat exchanger 123 during
the cooling operation of the air conditioner 100.
[0077] The outdoor heat exchanger 123 is connected to the outdoor
heat exchanger bypass passage 125 by a connecting passage 129 so
that the refrigerant passed through the outdoor expansion device
124 is introduced into the outdoor heat exchanger 123 when the air
conditioner is in a heating operation and the outdoor temperature
is lower than a set temperature.
[0078] A second heating on-off valve 130 for opening and closing
the connecting passage 129 is installed on the connecting passage
129.
[0079] Here, the cooling on-off valve 127 and the first heating
on-off valve 126 can be installed at the inside or outside of the
outdoor unit 120, but the description thereof. Will be made
hereinafter with respect to a case where they are installed at the
outside of outdoor unit 120.
[0080] The operation of the thus-constructed cogeneration system in
accordance with the exemplary embodiment of the present invention
will be described.
[0081] First, when the engine 62 is driven, the generator 61
produces electricity, and, as shown in FIGS. 2a to 4, the produced
electricity is supplied to the sub unit 80, the air conditioner 100
and so on.
[0082] Exhaust gas waste heat and cooling water waste heat of the
engine 62 are recovered by the cooling water heat exchanger 64, the
first exhaust gas heat exchanger 65, and the second exhaust gas
heat exchanger 66.
[0083] In a cooling operation of the air conditioner 100, as shown
in FIGS. 2a and 2b, a heat medium on the main unit heat medium
passage 52 recovers the waste heat of the engine 62 while
sequentially circulating through the cooling water heat exchanger
64, the second exhaust gas heat exchanger 66, and the first exhaust
gas heat exchanger 65.
[0084] The heat medium that has recovered the waste heat is
introduced into the sub unit 80 through the unit connecting passage
54.
[0085] At this time, since the air conditioner 100 is in the
cooling operation, the three-way valve 84 opens the radiation
passage 83, so that the heat medium introduced into the sub unit 80
is emitted to the air through the radiation heat exchanger 82.
[0086] And, in the air conditioner 100, the four-way valve 122 is
switched to a cooling mode.
[0087] Accordingly, the refrigerant compressed in the compressor
122 escapes the outdoor unit 120 through the four-way valve 122,
and is introduced into the sub unit 80 through the air conditioner
connecting passage 104 and the sub unit refrigerant passage
102.
[0088] The on-off valve 90 in the sub unit 80 is turned off, and
the refrigerant introduced into the sub unit refrigerant passage
102 passes through the bypass passage 87 and then enters the
outdoor unit 120.
[0089] That is, the waste heat supplying heat exchanger 81 is
bypassed.
[0090] Within the outdoor unit 120, the cooling valve 127 is turned
on, and the first and second heating on-off valves 126 and 129 are
turned off, thus the refrigerant introduced into the outdoor unit
120 passes through the outdoor heat exchanger 123 and then is
introduced into the indoor unit 110 through the air conditioner
refrigerant passage 103.
[0091] That is, in the cooling operation of the air conditioner
100, the refrigerant bypasses the waste heat supplying heat
exchanger 81 and is introduced into the outdoor heat exchanger 123,
so that the outdoor heat exchanger 123 serves as a condenser.
[0092] The refrigerant passed through the outdoor heat exchanger
123 passes through the air conditioner refrigerant passage 103, the
indoor expansion device 122, and the indoor heat exchanger 111.
[0093] Therefore, the indoor heat exchanger 111 serves as an
evaporator, and the indoor temperatures become lower.
[0094] On the other hand, if the air conditioner 100 is in a
heating operation and the outdoor temperature is lower than a set
temperature, as shown in FIG. 3, the refrigerant introduced into
the sub unit 80 through the unit connecting passage 54 through the
main unit 60 passes through the waste heat supplying heat exchanger
81.
[0095] In the air conditioner 100, the four-way valve 122 is
switched to a heating mode, thus the refrigerant compressed in the
compressor 121 is re-introduced into the outdoor unit 120 through
the four-way valve 122, the air conditioner connecting passage 103,
the indoor heat exchanger 111, the indoor expansion device 112, and
the air conditioner connecting passage 103.
[0096] At this time, the first heating on-off valve 126 is turned
on, and the second heating on-off valve 130 and the cooling on-off
valve 127 are turned off, thus the refrigerant re-introduced into
the outdoor unit 120 bypasses the outdoor heat exchanger 123 as it
passes through the outdoor heat exchanger bypass passage 125.
[0097] The refrigerant that has bypassed the outdoor heat exchanger
123 is introduced into the sub unit 80 through the air conditioner
connecting passage 104.
[0098] At this time, in the sub unit 80, the on-off valve 90 is
turned on, so the refrigerant introduced into the sub unit 80
passes through the waste heat supplying heat exchanger 81 and then
enters the outdoor unit 120.
[0099] That is, if the air conditioner 100 is in a heating
operation and the outdoor temperature is lower than a set
temperature, the indoor heat exchanger 111 serves as a condenser,
and the waste heat supplying heat exchanger 81 serves as an
evaporator.
[0100] Accordingly, the refrigerant is evaporated in the waste heat
supplying heat exchanger 81, so that it is possible to provide an
ever-constant heating performance regardless of changes in outdoor
temperature.
[0101] On the other hand, if the air conditioner 100 is in a
cooling operation, and the outdoor temperature is higher than a set
temperature, as shown in FIG. 4, the heat medium introduced into
the sub unit 80 through the unit connecting passage 54 from the
main unit 60 passes through the waste heat supplying heat exchanger
81.
[0102] In the air conditioner 100, the four-way valve 122 is
switched to a heating mode, thus the refrigerant compressed in the
compressor 121 is re-introduced into the outdoor unit 120 through
the four-way valve 122, the air conditioner connecting passage 103,
the indoor heat exchanger 111, the indoor expansion device 112, and
the air conditioner connecting passage 103.
[0103] At this time, the first heating on-off valve 126 is turned
off, and the second heating on-off valve 130 and the cooling on-off
valve 127 are turned on, thus the refrigerant re-introduced into
the outdoor unit 120 passes through the outdoor heat exchanger
123.
[0104] The refrigerant that has passed through the outdoor heat
exchanger 123 is introduced into the sub unit 80 through the air
conditioner connecting passage 104.
[0105] At this time, in the sub unit 80, the on-off valve 90 is
turned on, so the refrigerant introduced into the sub unit 80
passes through the waste heat supplying heat exchanger 81 and then
enters the outdoor unit 120.
[0106] That is, if the air conditioner 100 is in a heating
operation and the outdoor temperature is higher than a set
temperature, the indoor heat exchanger 111 serves as a condenser,
and the outdoor heat exchanger 123 and the waste heat supplying
heat exchanger 81 serve as an evaporator.
[0107] The main unit temperature sensor 74 senses a temperature of
the main unit heat medium passage 52 while the sub unit temperature
sensor 92 senses temperature of the sub unit refrigerant passage
102 and the radiation passage 83.
[0108] The main unit temperature sensor 74 transmits a sensing
signal to the main unit controller 73, and the main unit controller
73 controls the operation of the engine 62 or the like.
[0109] The sub unit temperature sensor 92 transmits a sensing
signal to the sub unit controller 91, and the sub unit controller
91 controls the passages of the heat medium and the refrigerant by
controlling the three-way valve 84, the on-off valve 90 and so
on.
[0110] The cogeneration system in accordance with the invention has
an advantage that a cogeneration section is divided into a main
unit and a sub unit, and an engine and a generator are included in
the main unit, to thus enable the main unit and the sub unit to be
installed at different locations, so that the main unit can be
installed on the ground floor or basement of a building to thus
minimize building vibrations or noises generated by a load, and the
sub unit can be installed near to an air conditioner to thus
minimize the length of a refrigerant passage, thereby reducing the
installation cost and the flow passage resistance.
[0111] Additionally, the sub unit can be installed on the roof, so
that the radiation effect of a radiator installed on the sub unit
can be enhanced.
[0112] Additionally, the waste heat recovered from the engine is
supplied to the air conditioner through the waste heat supplying
heat exchanger, so that the heating performance and efficiency can
be maximized.
[0113] Additionally, in the case that the air conditioner is in a
heating operation and the outdoor temperature is lower than a set
temperature, the refrigerant is evaporated by the waste heat
supplying heat exchanger, so that a constant heating performance
can be obtained regardless of the outdoor temperature, and frost
formation on an outdoor heat exchanger can be prevented.
* * * * *