U.S. patent application number 10/887289 was filed with the patent office on 2004-12-23 for heat extraction system for cooling power transformer.
Invention is credited to Longardner, Robert L..
Application Number | 20040255604 10/887289 |
Document ID | / |
Family ID | 46301451 |
Filed Date | 2004-12-23 |
United States Patent
Application |
20040255604 |
Kind Code |
A1 |
Longardner, Robert L. |
December 23, 2004 |
Heat extraction system for cooling power transformer
Abstract
A cooling system for controlling including a heat exchanger
defining a first interior space and a second interior space in
thermal exchange with one another. First interior space is in fluid
communication with the power transformer. A refrigeration system is
in fluid communication with second interior space and provides a
chillant to second interior space. A transformer cooling fluid
circulates through and between first interior space and the power
transformer. An energy source is operably coupled to the
refrigeration system and supplies heat energy to energize the
refrigeration system. In operation, thermal energy is absorbed by
transformer cooling fluid in the power transformer to thereby cool
the power transformer. In the heat exchanger thermal energy is
removed from transformer cooling fluid in first interior space and
is absorbed by chillant in second interior space to thereby cool
the transformer cooling fluid.
Inventors: |
Longardner, Robert L.;
(Indianapolis, IN) |
Correspondence
Address: |
BAKER & DANIELS
300 NORTH MERIDIAN STREET
SUITE 2700
INDIANAPOLIS
IN
46204-1782
US
|
Family ID: |
46301451 |
Appl. No.: |
10/887289 |
Filed: |
July 8, 2004 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
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10887289 |
Jul 8, 2004 |
|
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10351712 |
Jan 27, 2003 |
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Current U.S.
Class: |
62/238.3 |
Current CPC
Class: |
F02C 6/18 20130101; F25B
27/02 20130101; F02C 7/141 20130101; Y02A 30/274 20180101; F02C
7/143 20130101 |
Class at
Publication: |
062/238.3 |
International
Class: |
F25B 027/00 |
Claims
What is claimed is:
1. A cooling system for controlling the internal temperature of a
power transformer, the cooling system comprising: a heat exchanger
defining a first interior space and a second interior space, said
first interior space in a thermal exchange relationship with said
second interior space, said first interior space in fluid
communication with the power transformer; a refrigeration system in
fluid communication with said second interior space and providing a
chillant to said second interior space, said chillant circulating
through and between said second interior space and said
refrigeration system; a transformer cooling fluid circulating
through and between said first interior space and the power
transformer; and an energy source operably coupled to said
refrigeration system and supplying heat energy to energize said
refrigeration system, said energy source including at least one of
an air breathing heat engine (ABHE) and a steam turbine, wherein
during operation of the cooling system thermal energy is absorbed
by said transformer cooling fluid in the power transformer to
thereby cool the power transformer, and wherein in said heat
exchanger thermal energy is removed from said transformer cooling
fluid in said first interior space and is absorbed by said chillant
in said second interior space to thereby cool said transformer
cooling fluid.
2. The cooling system of claim 1 wherein said refrigeration system
is an absorption chiller.
3. The system of claim 2 wherein said absorption chiller employs
recovered heat energy from said energy source to energize a staged
process of concentration, condensation, evaporation and absorption
to provide said chillant.
4. The system of claim 1, wherein said transformer cooling fluid is
a liquid.
5. The system of claim 4 wherein said transformer cooling fluid
comprises an oil.
6. The system of claim 1 wherein one of said first and second
interior spaces is defined by an elongate tube, the other of said
first and second interior spaces is defined by a hollow coil
disposed within said elongate tube.
7. The system of claim 1 wherein said first interior space is
defined by a first coil and the second interior space is defined by
a second coil, said first and second coils in heat exchange with
one another.
8. The system of claim 1 further comprising a temperature control
valve operably connected to said power transformer, said
temperature control valve sensing the temperature of said power
transformer and controlling the communication of said transformer
cooling fluid from said power transformer to said first interior
space based on the sensed temperature.
9. The system of claim 1 wherein said energy source includes an air
breathing heat engine (ABHE), said ABHE including: a gas
conditioner defining a gas conditioning area, said gas conditioner
includes a conditioning heat exchanger and a sensible heat
exchanger, each of said conditioning heat exchanger and sensible
heat exchanger being disposed in said gas conditioner area; each of
said conditioning heat exchanger and sensible heat exchanger being
in fluid communication with said refrigeration system and receiving
said chillant from said refrigeration system; a combustor defining
an inlet port and a discharge port, said inlet port in fluid
communication with said gas conditioner area of said gas
conditioner; a waste recovery unit operably coupled to said
discharge port of said combustor; a post-combustion heat exchanger
operably coupled to said waste recovery unit and in fluid
communication with said refrigerant system, wherein during
operation of said ABHE air is received into said gas conditioning
area, thermal energy is transferred from said air to said chillant
in said conditioning heat exchanger and said sensible heat
exchanger to thereby condition said air, said combustor receiving
said conditioned air and producing an exhaust gas, said exhaust gas
containing thermal heat energy, said waste recovery unit receiving
exhaust gas, said post-combustion heat exchanger recovering thermal
heat energy in the exhaust gas and communicating said heat energy
to said refrigeration system.
10. The system of claim 9 wherein said refrigeration system
includes an absorption chiller, said absorption chiller employing
the recovered heat energy to energize a staged process of
concentration, condensation, evaporation and absorption to produce
said chillant.
11. A cooling system for improving the efficiency of the
manufacture and distribution of electricity, the system comprising:
a power transformer; a refrigeration system; a heat dissipation
device including a heat exchanger, said heat exchanger defining a
first interior space and a second interior space, said first
interior space in thermal exchange with said second interior space;
a refrigeration circuit through which a chillant circulates, said
refrigeration circuit having operably coupled thereto said
refrigeration system and said second interior space, wherein during
operation of the cooling system heat is removed from said chillant
in said refrigeration system and heat is added to said chillant in
said heat exchanger; a transformer cooling circuit through which a
transformer cooling fluid circulates, said transformer cooling
circuit having operably coupled thereto said power transformer and
said first interior space, wherein during operation of the cooling
system heat is absorbed by said transformer cooling fluid in said
power transformer and heat is transferred from said transformer
cooling fluid to said chillant in said heat exchanger; a heat
energy generating component, said heat energy generating component
generating heat energy and said refrigeration system utilizing the
heat energy to energize a process for circulating and removing heat
from said chillant.
12. The system of claim 11 further comprising a temperature control
valve operably connected to transformer cooling circuit, said
temperature control valve sensing the temperature of said power
transformer and controlling the circulation of said transformer
cooling fluid through said transformer cooling circuit.
13. The system of claim 11 wherein said process for circulating and
removing heat from said chillant includes staged processes of
concentration, condensation, evaporation and absorption.
14. The system of claim 11, wherein said heat generating component
includes at least one of an air breathing heat engine (ABHE) and a
steam turbine.
15. The system of claim 111 wherein said refrigeration system
includes an absorption chiller, said chiller employing the heat
energy to energize a staged process of concentration, condensation,
evaporation and absorption to provide the chillant.
16. The system of claim 11, wherein one of said first and second
interior spaces is defined by an elongate tube, the other of said
first and second interior space is defined by a hollow coil
disposed within said elongate tube.
17. The system of claim 11, wherein said transformer cooling fluid
is a liquid.
18. The system of claim 11, wherein said heat energy generating
component comprises an air breathing heat engine (ABHE), said ABHE
includes: a combustor; a waste recovery unit operably coupled to
said combustor; and a post-combustion heat exchanger operably
coupled to said waste recovery unit and in fluid communication with
said refrigerant system, wherein during operation of said ABHE said
combustor produces an exhaust gas, said exhaust gas containing heat
energy, said waste recovery unit receiving said exhaust gas, said
post-combustion heat exchanger recovering heat energy from the
exhaust gas and communicating said heat energy to said
refrigeration system.
19. The system of claim 18 wherein said ABHE further includes a
shaft operably driven by said combustor, and a power generator
drivingly connected to said shaft to actuate said power
generator.
20. The system of claim 19 further comprising a generator cooling
circuit through which a generator cooling fluid circulates, said
generator cooling circuit having operably coupled thereto said
generator and said refrigeration system, wherein during operation
of the cooling system said generator cooling fluid absorbs heat in
said generator to cool said generator and heat is removed from said
generator cooling fluid in said refrigeration system.
21. The system of claim 19 further comprising: a generator heat
exchanger defining a first interior path and a second interior
path, said first interior path in heat exchange with said second
interior path; a generator cooling circuit through which a
generator cooling fluid circulates, said generator cooling circuit
having operably coupled thereto said generator and said first
interior path; and a generator refrigeration circuit through which
the chillant circulates, said second refrigeration circuit having
operably coupled thereto said refrigeration system and said second
interior path, wherein during operation of the cooling system heat
is absorbed by said generator cooling fluid in said generator to
cool said generator and heat is transferred from said generator
cooling fluid to said chillant in said generator heat
exchanger.
22. The system of claim 11 wherein said heat energy generating
component includes a steam turbine operably coupled to said
refrigeration system, said steam turbine generating hot water, said
hot water containing heat energy, said steam turbine communicating
said hot water and said heat energy to said refrigeration system,
said refrigeration system employing the heat energy to energize a
staged process of concentration, condensation, evaporation and
absorption to produce said chillant.
23. A method for controlling the internal temperature of one or
more components of a system for generating and distributing
electricity, the method comprising the steps of: circulating a
transformer cooling fluid through a transformer cooling circuit,
the transformer cooling circuit having operably coupled thereto a
power transformer and a heat exchanger, whereby heat is absorbed by
the transformer cooling fluid in the power transformer and heat is
extracted from the transformer cooling fluid in said heat
exchanger; and circulating a chillant through a refrigeration
circuit, the refrigeration circuit having operably coupled thereto
the heat exchanger and a refrigeration system, whereby heat is
extracted from the chillant in the refrigeration system and heat is
absorbed by the chillant in the heat exchanger.
24. The method of claim 23 further comprising the step of:
generating heat energy to energize the refrigeration system using
an air breathing heat engine (ABHE), the step of generating heat
energy using the ABHE including the steps of: producing an exhaust
gas containing heat energy by combustion; discharging the exhaust
gas into a waste heat recovery unit; and recovering the heat energy
contained in the exhaust gas by circulating a working fluid through
an energy recovery circuit, the energy recovery circuit operably
coupled to the refrigeration system and a second heat exchanger,
the second heat exchanger operably coupled to the waste heat
recovery unit, whereby heat energy is transferred from the exhaust
gas to the working fluid in the second heat exchanger and the
working fluid is circulated to the refrigeration system wherein
said refrigeration system employs the heat energy to energize a
staged process of concentration, condensation, evaporation and
absorption.
25. The method of claim 24 wherein the working fluid comprises the
chillant.
26. The method of claim 23 further comprising the step of
generating heat energy to energize the refrigeration system using a
steam turbine, the step of generating heat energy using the steam
turbine including the steps of: generating hot water using the
steam turbine, the hot water containing heat energy; communicating
the hot water and the heat energy contained therein to the
refrigeration system; and the refrigeration system employing the
heat energy to energize a staged process of concentration,
condensation, evaporation and absorption.
27. The method of claim 23 further comprising the step of
regulating the circulation of transformer cooling fluid through the
transformer cooling circuit by sensing the temperature of the power
transformer, communicating the sensed temperature to a temperature
control valve, the temperature control valve operably coupled to
transformer cooling circuit, the temperature control valve
restricting the circulation of the transformer cooling fluid when
the sensed temperature is below a pre-determined value and
permitting the circulation of the transformer cooling fluid when
the sensed temperature is above a pre-determined value.
28. The method of claim 23, wherein the refrigeration system
includes an absorption chiller.
29. The method of claim 23 further comprising the steps of:
circulating a generator cooling fluid through a generator cooling
circuit, the generator cooling circuit having operably coupled
thereto a generator and a generator heat exchanger, whereby heat is
absorbed by the generator cooling fluid in the generator and heat
is extracted from the generator cooling fluid in the generator heat
exchanger; and circulating the chillant through a generator
refrigeration circuit, the generator refrigeration circuit having
operably coupled thereto the generator heat exchanger and the
refrigeration system, whereby heat is extracted from the chillant
in the refrigeration system and heat is transferred from the
generator cooling fluid to the chillant in the generator heat
exchanger.
Description
PRIORITY REFERENCE
[0001] This application is a continuation-in-part application
claiming priority under 35 U.S.C. .sctn.120 to pending U.S. patent
application Ser. No. 10/351,712 filed Jan. 27, 2003.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention.
[0003] The present invention relates to power transformers, which
may be step-up or step-down transformers.
[0004] 2. Description of the Related Art
[0005] The manufacturing of electricity begins at the power plant,
where a turbine engine driven by fuels such as natural gas, oil,
and coal, is used to produce electricity. The turbine engine is
operably connected to a generator via a shaft. The generator
includes a large magnet surrounded by coiled copper wire. The
turbine causes the magnet to rotate inside the coils, which
generates electricity by creating a current in each coil. Such
turbine engines are commonly in the form of either steam turbines,
which burn the fuel in a boiler and produce high pressure steam, or
air breathing heat engines (ABHE), which burn the fuel in a
combustor and produce an exhaust gas.
[0006] From the generator, the power is "stepped up" to a very high
voltage by a large power transformer for more economical
transmission over long distances to different substations. A
substation may include an electrical apparatus that generally
transforms the voltage to lower levels. From the substations the
power then travels to other distribution transformers. These
distribution transformers reduce the voltage to the 120-volt and
240-volt levels required for appliances and equipment. From the
distribution transformers, the power is channeled to distribution
panels and home circuit breakers. It is at this point that the
power is divided up into several circuits that serve different
loads.
[0007] Generally, transformers are highly efficient and can deliver
practically the full power received. However, transformer losses,
typically in the form of heat, can reduce transformer efficiency,
resulting in a reduction of load capacity and service. Examples of
transformer losses affected by heat and load which can be metered
are: copper loss, hysteresis loss, eddy current loss, iron loss,
no-load loss, and impedance loss. In addition, heat from
transformer losses can degrade the insulation of the transformer,
thus reducing the life of the transformer. Heat losses can
similarly occur in the generator, thereby reducing the efficiency
of the generator and reducing the life of the generator.
[0008] It is prudent to manage transformer and generator losses by
preventing overheating. Known systems address the overheat problem
of power transformer by using fans or other cooling mechanisms such
as cooling oil baths. These systems commonly utilize external
sources of energy, and therefore, can reduce efficiency and
increase operating costs. Accordingly, a need remains for an
efficient system for controlling the internal temperature of the
transformer and/or generator.
SUMMARY OF THE INVENTION
[0009] The present invention provides a cooling system for
controlling the internal temperature of the components of a power
manufacturing system. In one embodiment the cooling system is
adapted to cool a power transformer. The cooling system includes a
heat exchanger defining a first interior space and a second
interior space. The first interior space is in a thermal exchange
relationship with the second interior space and the first interior
space is in fluid communication with the power transformer. A
refrigeration system is in fluid communication with the second
interior space and provides a chillant to the second interior
space. The chillant circulates through and between the second
interior space and the refrigeration system. A transformer cooling
fluid circulates through and between the first interior space and
the power transformer. An energy source is operably coupled to the
refrigeration system and supplies heat energy to energize the
refrigeration system. The energy source includes an air breathing
heat engine (ABHE) or a steam turbine. During operation of the
cooling system, thermal energy is absorbed by the transformer
cooling fluid in the power transformer to thereby cool the power
transformer. In the heat exchanger thermal energy is removed from
the transformer cooling fluid in the first interior space and is
absorbed by the chillant in the second interior space to thereby
cool the transformer cooling fluid.
[0010] In another embodiment, the present invention provides a
cooling system for improving the efficiency of the manufacture and
distribution of electricity. The cooling system includes a power
transformer, a refrigeration system, a heat dissipation device, a
refrigeration circuit through which a chillant circulates, a
transformer cooling circuit through which a transformer cooling
fluid circulates, and a heat energy generating component. The heat
dissipation device includes a heat exchanger defining a first
interior space and a second interior space. The first interior
space is in thermal exchange with the second interior space. The
refrigeration circuit is operably coupled to the refrigeration
system and the second interior space, wherein during operation of
the cooling system heat is removed from the chillant in the
refrigeration system and heat is added to the chillant in the heat
exchanger. The transformer cooling circuit is operably coupled to
the power transformer and the first interior space, wherein during
operation of the cooling system heat is absorbed by the transformer
cooling fluid in the power transformer and heat is transferred from
the transformer cooling fluid to the chillant in the heat
exchanger. The heat generating component generates heat energy and
the refrigeration system utilizes the heat energy to energize a
process for circulating and removing heat from the chillant.
[0011] The present invention also provides a method for controlling
the internal temperature of one or more components of a system for
generating and distributing electricity. The method includes the
steps of circulating a transformer cooling fluid through a
transformer cooling circuit, the transformer cooling circuit having
operably coupled thereto a power transformer and a heat exchanger,
whereby heat is absorbed by the transformer cooling fluid in the
power transformer and heat is extracted from the transformer
cooling fluid in the heat exchanger; and circulating a chillant
through a refrigeration circuit, the refrigeration circuit having
operably coupled thereto the heat exchanger and a refrigeration
system, whereby heat is extracted from the chillant in the
refrigeration system and heat is absorbed by the chillant in the
heat exchanger.
[0012] One advantage of the invention is that it provides the
method for cooling the inner working of a transformer for all
atmospheric and load conditions while other directed chillant is
conditioning the ambient air stream to the ABHE which magnifies the
amount of electrical energy for retail by 20-30% when ambient
temperatures are around 95.degree. F. (35.degree. C.) compared to
the through-put for turbine ISO or transformer nameplate rating.
The chillant provides the means to protect the transformer against
the damage of temperature rise due to the heat gain in the inherent
losses.
BRIEF DESCRIPTION OF THE DRAWINGS
[0013] The above-mentioned and other features and advantages of
this invention, and the manner of attaining them, will become more
apparent and the invention itself will be better understood by
reference to the following description of embodiments of the
invention taken in conjunction with the accompanying drawings,
wherein:
[0014] FIG. 1 is a diagram showing an embodiment of a power
transformer cooling system according to one embodiment of the
present invention;
[0015] FIG. 2 is a diagram of a power transformer cooling system
according to another embodiment of the present invention, wherein
the energy source is an ABHE;
[0016] FIG. 3 is a diagram of a power transformer cooling system
according to yet another embodiment of the present invention,
wherein the energy source is a steam turbine; and
[0017] FIG. 4 is a diagram of a power transformer/generator cooling
system according to another embodiment of the present
invention.
[0018] Corresponding reference characters indicate corresponding
parts throughout the several views. Although the drawings represent
embodiments of the present invention, the drawings are not
necessarily to scale and certain features may be exaggerated in
order to better illustrate and explain the present invention. The
exemplification set out herein illustrates an embodiment of the
invention, in one form, and such exemplifications are not to be
construed as limiting the scope of the invention in any manner.
DETAILED DESCRIPTION OF THE INVENTION
[0019] The embodiments disclosed below are not intended to be
exhaustive or limit the invention to the precise form disclosed in
the following detailed description. Rather, the embodiments are
chosen and described so that others skilled in the art may utilize
the teachings.
[0020] Referring now to FIGS. 1 and 2, cooling system 10 for
improving the efficiency of the manufacture and distribution of
electricity is illustrated. Cooling system 10 generally includes
power transformer 20, heat exchanger 31, and refrigeration system
60. Power transformer 20 may be any conventional transformer used
to step up or step down the voltage electrical power. Power
transformer 20 generates heat through transformation losses such as
heat due to resistance flow of current, heat due to hysteresis,
heat due to eddy currents, and heat due to no-load. The efficiency
of transformer 20 can be calculated in terms of energy units
(kilowatt hour, Kwh):
Efficiency=Output/Input=Output (Kwh)/[Output (Kwh)+Heat loss
(Kwh)]
[0021] The voltage regulation of transformer 20 is the percentage
change in the output voltage from no-load to full-load. [%
Regulation=(no-load voltage-load voltage).times.100/load voltage)].
Ideally, there should be no change in the transformer's output
voltage from no-load to full-load. In such a case, the voltage
regulation is 0%. To get the best performance out of a transformer,
it is necessary to have the lowest possible voltage regulation.
[0022] Power transformer 20 may be any commercially available
transformer, such as any one of the common classes of transformers
listed in TABLE 1.
1TABLE 1 The most common classes of transformer THE MOST COMMON
CLASSES OF TRANSFORMER CLASS COOLING METHOD OA OUTSIDE-AIR
SELF-COOLED (BY CONVECTION) OA/FA OUTSIDE-AIR/FAN-AIR SELF-COOLED
OR FAN COOLED OA/FA/FA OUTSIDE-AIR W/2 FAN COOLING SETS
SELF-COOLED/FAN COOLED OA/FA/FOA OUTSIDE-AIR/FAN-AIR/FORCED
(PUMPED) OIL SELF-COOLED, FAN COOLED PUMPED OIL FOA FORCED OIL/FAN
COOLED PUMPED OIL WITH FANS AA AIR-AIR DRY TYPE (OR CAST
INSULATION) SELF COOLED (BY CONVECTION) AA/FA AIR-AIR/FAN-AIR IN
DRY TYPE SELF-COOLED WITH FANS
[0023] Power transformer 20 may have various built-in overload
capabilities, and existing cooling method as shown in TABLE 1. The
existing cooling method requires a supply of external energy. For
example, a cooling fan requires a connection to an outside
electrical source. The existing cooling method may be replaced or
complemented by system 10 of the present invention.
[0024] Turning back to FIGS. 1 and 2, heat exchanger 31 has a
shell-and-tube design including elongated tube 29 defining first
interior space 32, and hollow coil 33 disposed within first
interior space 32. Although heat exchanger 31 is illustrated as
having a shell-and-tube design, it should be understood that heat
exchanger 31 may be of any known heat exchanger design including,
for example, a dual heat transfer coil having a tube within tube
construction. Tube 29 defines tube inlet 36 and tube outlet 37,
each of which are in fluid communication with first interior space
32. Hollow coil 33 extends along the length of tube 29 and defines
second interior space (not shown). Coil 33 also defines inlet coil
connection 41 at one end and outlet coil connection 40 at the
opposite end, each of which communicate with second interior space
(not shown).
[0025] Cooling system 10 further includes a transformer cooling
circuit 26 through which a transformer cooling fluid circulates.
Transformer cooling fluid may be any fluid capable of absorbing the
heat of power transformer 20. Suitable transformer cooling fluids
include oil, such as dielectric oils. Transformer cooling circuit
26 includes medium line 24, which fluidly connects power
transformer 20 to heat exchanger 31. More specifically, medium line
24 includes first end 34 fluidly connected to power transformer 20,
and second end 35 fluidly connected via tube inlet 36 to interior
space 32 of tube 29. Transformer cooling circuit 26 also includes
medium return line 25, which fluidly connects power transformer 20
to heat exchanger 31. Medium return line 25 includes a first end 43
in fluid communication with interior space 32 of heat exchanger 31
through tube outlet 37, and second end 44 in fluid communication
with power transformer 20.
[0026] Cooling system 10 also includes a refrigeration circuit 27
through which a chillant circulates. The chillant may be any
conventional chillant or refrigerant useful in refrigeration
systems, especially those chillants useful in absorption chillers,
such as those described in U.S. Pat. No. 4,936,109. Refrigeration
circuit 27 includes first chillant line 52 and first chillant
return line 53, each of which communicate fluid between heat
exchanger 31 and refrigeration system 60. First chillant line 52
has first end 55, operably connected to and in fluid communication
with refrigeration system 60, and second end 54 connected to and in
fluid communication with second interior space of hollow coil 33
via inlet coil connection 41. First chillant return line 53 has
first end 57 connected to and in fluid communication with second
interior space of hollow coil 33 via outlet coil connection 40, and
second end 56 operably connected to and in fluid communication with
refrigeration system 60.
[0027] Refrigeration system 60 may be any suitable absorption
chiller or refrigeration generator available in the market.
Examples of absorption chillers and refrigeration generators that
can be used in cooling system 10 are described in U.S. Pat. No.
4,936,109, the disclosure of which is hereby fully incorporated by
reference. Generally, an absorption chiller or a refrigeration
generator employs heat energy from an energy source to energize a
staged process of concentration, condensation, evaporation and
absorption to provide a chillant for cooling purposes. The chillant
may be in a fluid form, such as water, gas, oil, or mixture
thereof.
[0028] As depicted in FIGS. 1 and 2, in operation, refrigeration
system 60 produces a cool chillant that is transferred through
first chillant line 52 and into second interior space of hollow
coil 33 via inlet coil connection 41. The initial temperature of
this cool chillant may be about 50.degree. F. (10.degree. C.). At
the same time, transformer cooling fluid circulates through power
transformer 20, during which heat energy from transformer losses is
absorbed by the transformer cooling fluid in power transformer 20.
As a result, power transformer 20 is cooled and the transformer
cooling fluid is heated.
[0029] The heated transformer cooling fluid flows from power
transformer 20 through medium line 24 to heat exchanger 31. At heat
exchanger 31 the transformer cooling fluid enters interior space 32
of tube 29 through tube inlet 36. While in tube 29, heat energy is
transferred from transformer cooling fluid to the cool chillant in
second interior space of hollow coil 33 by a heat transfer process,
such as conduction, convection and radiation. This heat transfer
(heat exchange) results in cooling the transformer cooling fluid
and heating the chillant. As a result of the heat exchange, the
temperature of heated chillant may reach a about 80.degree. F.
(29.4.degree. C.). The resulting cool transformer cooling fluid
then exits tube 29 via tube outlet 37 and enters medium return line
25, which returns the cool transformer cooling fluid back to power
transformer 20 for further cooling transformer 20 and the process
(circulation) is repeated. Meanwhile, the heated chillant exits
hollow coil 33 through outlet coil connection 40 and is returned
via chillant return line 53 to refrigeration system 60 wherein the
chillant is cooled and recirculated through refrigeration circuit
27.
[0030] It should also be understood that heat exchanger 31 may have
any design capable of placing the chillant and cooling fluid in
heat exchange with one another. In addition, heat exchanger 31 may
be adapted so that the chillant flows through the first interior
space 32 of tube 29 and the cooling fluid flows through coil
33.
[0031] In another embodiment of the present invention illustrated
in FIGS. 1 and 2, first end 34 of first medium line 24 is connected
to power transformer 20 through valve 50, which is adapted to
permit the flow of transformer cooling fluid through medium line 24
when the internal temperature of power transformer 20 reaches a
predetermined temperature, and restrict the flow when the internal
temperature of power transformer 20 drops below the predetermined
temperature. When the temperature of heated medium reaches a
pre-determined temperature, valve 50 opens to release heated medium
into medium line 24.
[0032] In another embodiment of the present invention, shown
particularly in FIG. 2, the energy source for refrigeration system
60 of cooling system 10 is an air breathing heat engine (ABHE) 70,
such as that disclosed in U.S. Pat. No. 6,082,094, which is hereby
incorporated by reference. ABHE 70 generally includes air
conditioner 72, combustion turbine 100, and waste heat recovery
unit 111. Air conditioner 72 defines air conditioner area 75 and
includes air intake vents 73, which communicate air to air
condition area 75. Disposed within air condition area 75 is air
conditioning coil 74 and sensible cooling coil 78. Air conditioning
coil 74 and sensible cooling coil 78 are in fluid communication
with, and receive cool chillant from, refrigeration system 60 via
second refrigeration circuit 80.
[0033] Second refrigeration circuit 80 includes second chillant
feed line 82, which is fluidly joined at one end to chillant line
52 of first refrigeration circuit 27, thereby fluidly communicating
with refrigeration system 60. The opposite end of second chillant
feed line 82 is split into chillant feed sub-lines 82a, 82b, which
are fluidly connected to the inlet ends of air conditioning coil 74
and sensible cooling coil 78, respectively. Second refrigeration
circuit 80 also includes second chillant return line 83, which is
fluidly connected at one end to chillant return line 53 of first
refrigeration circuit 27, thereby fluidly communicating with
refrigeration system 60. The opposite end of second chillant return
line 83 is split into chillant return sub-lines 83a, 83b, which are
fluidly connected to the outlet ends of air conditioning coil 74
and sensible cooling coil 78, respectively. Air conditioner 72 may
also include de-misters 77 disposed within air conditioning area 75
for removing additional moisture from the air in air conditioning
area 75.
[0034] In an alternative embodiment (not shown), second chillant
line 82 may be in direct communication with refrigeration system
60, without first joining first chillant line 52. Similarly, second
chillant return line 83 may be in direct communication with
refrigeration system 60, without first joining first chillant
return line 53. In this specific embodiment, second chillant line
82 extends directly from refrigeration system 60. Likewise, second
chillant return line 83 extends directly to refrigeration system
60.
[0035] Combustion turbine 100 includes intake port 101, turbine
102, and exhaust port 108. Intake port 101 is in fluid
communication with air conditioning area 75 to receive conditioned
intake air. Turbine 102 is in fluid communication with intake port
101 and exhaust port 108. Turbine 102 is operably coupled to shaft
103, which, in turn, is operably coupled to generator 106. Waste
heat recovery unit 111 includes exhaust port 110, which is fluidly
coupled to exhaust port 108 to receive exhaust gas produced by
combustion turbine 100.
[0036] Waste heat recovery unit 111 also includes exhaust stack or
flue 109 and a post combustion heat exchanger 112, which is in heat
exchange with the interior of exhaust stack 109. Heat exchanger 112
may include any number of heat exchange coils. As shown in FIG. 3,
heat exchanger 112 has a top coil 114 and bottom coil 115. Each of
top and bottom coils 114, 115 are fluidly coupled to refrigeration
system 60 via an energy recovery circuit 117 through which a
working fluid is circulated. The working fluid may be any fluid
capable of absorbing and releasing energy. In one embodiment, the
chillant flowing in the first and second refrigeration circuits
serves as the working fluid. Energy recovery circuit 117 includes
chillant supply line 116 and chillant return line 118, each of
which are operably coupled at one end to refrigeration system 60.
The opposite end of chillant supply line 116 splits into sub-lines
116a, 116b, which are fluidly coupled to the inlet end of top and
bottom heat exchange coils 114, 115, respectively. The opposite end
of chillant return line 118 splits into sub-lines 118a, 118b, which
are fluidly coupled to the outlet ends of top and bottom heat
exchange coils 114, 115, respectively.
[0037] In operation, air is drawn into conditioning area 75 through
air intake vents 73 and flows through air conditioning coil 74,
whereby heat energy in the air is transferred by a heat exchange
process to the chillant contained in air conditioning coil 74,
thereby cooling and conditioning the air. The conditioned air then
passes de-misters 77 whereby moisture is removed from the air to
further condition the air. The conditioned air then flows through
sensible cooling coil 78, whereby additional heat energy is
transferred from the air to the chillant in sensible cooling coil
78, thereby further cooling the air and heating the chillant. The
heated chillant from conditioning coil 74 and sensible cooling coil
78 flows to second return chillant line 83 via sub-lines 83a, 83b,
respectively. Second return chillant line 83 transfers the chillant
to return line 52 which, in turn, returns the chillant to
refrigeration system 60. Refrigeration system 60 cools the chillant
and circulates cool chillant through second refrigeration circuit
80. In one example, chillant 62 has a temperature of 42.degree. F.
(5.6.degree. C.) when it is supplied to sensible cooling coil 78
and air conditioning coil 74, whereas, heated chillant returning to
refrigeration system 60 may have a temperature of 52.degree. F.
(11.degree. C.).
[0038] Meanwhile, conditioned air from air conditioning area 75
flows through intake port 101 to turbine 102 where it is mixed with
injected fuel and is ignited resulting in a combustion force that
drives shaft 103. The rotation of shaft 103 actuates generator 106
to produce electricity. The combustion of the fuel and air produces
a hot exhaust gas containing energy in the form of the heat of
combustion. The hot exhaust gas, produced as a result of the
combustion, is discharged from turbine 102 via exhaust port 108 and
enters waste heat recovery unit 111 via exhaust port 110. In waste
heat recovery unit 111, the hot exhaust gas flows up exhaust stack
or flue 113, wherein it enters into heat exchange with combustion
heat exchanger 112 positioned within flue 113. The exhaust gas
flows through bottom chillant coil 115 and top chillant coil 114,
wherein the heat energy contained in the exhaust gas is absorbed by
the working fluid in top chillant coil 114 and bottom chillant coil
115.
[0039] Heat energy from exhaust gas 107 in waste recovery unit 111
is captured in the working fluid or chillant within top chillant
coil 114 and bottom chillant coil 115. The resulting heated working
fluid exits top and bottom coils 114, 115 via sub-lines 118a, 118b,
respectively. The heated working fluid then flows through chillant
return line 118 to refrigeration system 60. The heat energy stored
in the working fluid is used by refrigeration system 60 to produce
cool chillant, as described above and in U.S. Pat. No.
4,936,109.
[0040] In a specific embodiment of the present invention (not
shown), the air breathing heat engine may further include an
acoustic enclosure, as described in U.S. Pat. No. 6,082,094, the
disclosure of which is herein incorporated by reference.
Refrigeration system 60 may supply chillant for ventilating the
acoustic enclosure via appropriate chillant supply line connection
(not shown) or through an additional heat exchanger placed within
the acoustic enclosure, or as described in U.S. Pat. No.
6,082,094.
[0041] In another embodiment shown in FIG. 3, refrigeration system
60 is powered by steam turbine system 120, which is connected to
and in fluid communication with refrigeration 60 via an energy
recovery circuit 217. Refrigeration system 60 is connected to power
transformer 20 in the same fashion, as shown in FIG. 1. Generally,
steam turbine system 120 releases heat energy in the form of hot
water, which is transferred to refrigeration system 60 for use in
the production of cool chillant.
[0042] Steam turbine system 120 may be any known steam turbine. For
example, as depicted in FIG. 3, steam turbine system 120 includes
steam turbine engine 121 and steam condenser 122 in communication
with turbine engine 121. Turbine engine 121 includes shaft 125
connected to power generator 126, or other machine or equipment
that is operable using power from an engine. Steam turbine engine
121 receives condensate and/or steam from a source, which can be a
boiler of a compatible capacity. The condensed steam enters steam
turbine 121 through steam inlet pipe 128 and expands in turbine
engine 123, with an output of power driving shaft 125 to actuate
power generator 126. After complete expansion, the expanded steam
flows to steam condenser 122 from turbine engine 123 through an
appropriate exhaust steam casing (not shown), and is condensed to
hot water having a temperature of about 210.degree. F.
(98.9.degree. C.). Expanded steam or hot water can be returned to
the steam source or the boiler through return pipe 129. Hot water
containing heat energy, may also flow through first hot water pipe
132 from condenser 122 to refrigeration system 60. Refrigeration
system 60 uses the heat energy for the production of chillant for
cooling power transformer 20 (see FIG. 1).
[0043] Additional hot water or working fluid may flow from
condenser 122 through second hot water pipe 134 to hot water heater
140, which is connected to steam turbine 121. It is also possible
to have excess steam from turbine engine 123 to flow through steam
pipe 136 to supply heat to hot water heater 140. Hot water flowing
through refrigeration system 60, wherein a portion of heat is
extracted from hot water for the production of chillant, may be
returned to hot water heater 140 through third hot water pipe 142.
Output hot water 150 from hot water heater 140 can be distributed
for various heating purposes.
[0044] In a specific embodiment (not shown), condenser may contain
a heat exchanger that can capture heat energy from condensing the
steam. The captured heat energy can then be transferred to
refrigeration system 60, similar to what has been discussed above
as relating to the ABHE.
[0045] Further, it is possible to combine the embodiments shown in
FIGS. 2 and 3, so that both steam turbine 121 and air breathing
heat engine 100 are components of the same system. Both turbine 121
and air breathing heat engine 100 may produce heat energy that
together can be supplied to refrigeration system 60. In addition,
if air breathing heat engine 100 produces excess heat, the heat
energy may be used to heat the water in the connected hot water
heater 140. For particular applications and circumstances, the
amount of generated heat apportioned to refrigeration system and
hot water heater 140 may be adjusted.
[0046] In yet another embodiment, the cooling system may be adapted
to cool the generator in addition to, or instead of, the power
transformer. Turning to FIG. 4, for example, cooling system 10 is
adapted to cool generator 106 in addition to power transformer 20
(FIG. 2). Cooling system 10 includes generator heat exchanger 172,
generator refrigeration circuit 170 through which the chillant
circulates, and generator cooling circuit 180 through which a
generator cooling fluid circulates. Generator cooling fluid may be
any fluid capable of absorbing and releasing heat, such as known
refrigerants, water, oil, and gas. Generator heat exchanger 172 is
similar to heat exchanger 31 (FIGS. 1 and 2) and includes tube 174
defining first interior path 175, and hollow coil 176 disposed
within first interior path 175 and defining a second interior path
(not shown). Generator refrigeration circuit 170 fluidly connects
refrigeration system 60 to generator heat exchanger 172 and
includes chillant feed line 178 and chillant return line 179.
Chillant feed line 178 is fluidly coupled at one end to chillant
line 52, which fluidly connects line 178 to refrigeration system
60. The opposite end of chillant feed line 178 is fluidly coupled
to the inlet end of the second interior path of hollow coil 176.
Chillant return line 179 is fluidly coupled to the outlet end of
the second interior path of hollow coil 176. The opposite end is
fluidly coupled to return line 53 which fluidly connects to
refrigeration system 60. Generator cooling circuit 180 fluidly
connects generator 106 to generator heat exchanger 172 and includes
cooling fluid feed line 182 and cooling fluid return line 184.
Cooling fluid feed line 182 is fluidly coupled to generator 106 at
one end and to the inlet of first interior path 175 of tube 174 at
the opposite end.
[0047] In operation, refrigeration system 60 supplies cool chillant
to chillant feed line 178 via chillant line 52. The cool chillant
flows through feed line 178 and enters the second interior path of
hollow coil 176. In the meantime, generator cooling fluid flowing
in generator 106 absorbs the heat of generator 106 to thereby cool
generator 106 and heat the generator cooling fluid. The heated
generator cooling fluid exits generator 106 and enters fluid feed
line 182. The heated cooling fluid flows through feed line 182 to
generator heat exchanger 172 where it enters first interior path
175 of tube 174. In heat exchanger 172 heat is transferred from the
cooling fluid in first interior path 175 of tube 174 to the
chillant in hollow coil 17, thereby cooling the cooling fluid and
heating the chillant. The resulting heated chillant exits tube 174
and flows via return line 179 to chillant return line 53. The
heated chillant then flows via return line 53 to refrigeration
system 60 where the heat of the chillant is removed to provide cool
chillant, and the process is repeated. Meanwhile, the cooled
cooling fluid exits tube 174 and enters fluid return line 184,
which returns the cooled cooling fluid to generator 106. The cooled
cooling fluid absorbs additional heat from generator 106 and the
process is repeated.
[0048] As in the case with the power transformer 20, a valve (not
shown) may be operably coupled to generator cooling circuit 180 to
control the flow of cooling fluid in response to the temperature of
the generator 106 and/or cooling fluid in generator 106.
[0049] In another embodiment (not shown), the generator may be
cooled directly by chillant thereby eliminating the need for the
generator heat exchanger and generator cooling fluid. In this
embodiment, chillant would circulate through and directly between
the refrigeration system and the generator.
[0050] It should also be understood that heat exchanger 172 may
have any design capable of placing the chillant and cooling fluid
in heat exchange with one another. In addition, heat exchanger 172
may be adapted so that the chillant flows through the first
interior path 175 of tube 174 and the cooling fluid flows through
coil 176.
[0051] It is one advantage of the present invention to protect
power transformer 20 and/or the generator by keeping power
transformer 20 at a suitable temperature, regardless of the ambient
temperature. It is another advantage of the present invention to
use one on-line refrigeration system 60 to produce chillant for
cooling different components of a power generation system.
Refrigeration system 60 takes advantage of heat energy that is
released from internal sources within the system, and minimizes
external energy requirements.
[0052] While the present invention has been described as having a
preferred design, the present invention can be further modified
within the spirit and scope of this disclosure. This application is
therefore intended to cover any variations, uses, or adaptations of
the invention using its general principles. Further, this
application is intended to cover such departures from the present
disclosure as come within known or customary practice in the art to
which this invention pertains.
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