U.S. patent application number 13/314928 was filed with the patent office on 2012-04-05 for thermoelectric comfort control system for motor vehicle.
This patent application is currently assigned to FORD GLOBAL TECHNOLOGIES, LLC. Invention is credited to James George Gebbie, Kenneth J. Jackson, Clay Wesley Maranville.
Application Number | 20120079837 13/314928 |
Document ID | / |
Family ID | 45888639 |
Filed Date | 2012-04-05 |
United States Patent
Application |
20120079837 |
Kind Code |
A1 |
Maranville; Clay Wesley ; et
al. |
April 5, 2012 |
Thermoelectric Comfort Control System for Motor Vehicle
Abstract
A temperature control apparatus for an interior of a motor
vehicle having a temperature control loop circulating a
heat-exchange fluid to a drivetrain component. A thermoelectric
heat-pump (Peltier device) is disposed in the vehicle to heat or
cool the desired area, and a fluid comfort control loop exchanges
heat with the thermoelectric heat-pump and with the drivetrain
temperature control loop, increasing the net amount of heating or
cooling that can be delivered to the desired location by the
thermoelectric heat-pump. The comfort control loop may branch from
the drivetrain loop and carry a portion of the heat-exchange fluid
carried in the drivetrain loop. Alternatively, the comfort control
loop may carry a second heat-exchange fluid that remains separate
from the heat-exchange fluid of the drivetrain loop and exchanges
heat therewith in a heat exchanger.
Inventors: |
Maranville; Clay Wesley;
(Ypsilanti, MI) ; Gebbie; James George; (Rochester
Hills, MI) ; Jackson; Kenneth J.; (Dearborn,
MI) |
Assignee: |
FORD GLOBAL TECHNOLOGIES,
LLC
Dearborn
MI
|
Family ID: |
45888639 |
Appl. No.: |
13/314928 |
Filed: |
December 8, 2011 |
Current U.S.
Class: |
62/3.61 |
Current CPC
Class: |
B60H 1/00478 20130101;
B60H 1/00285 20130101; B60N 2/5635 20130101; B60N 2/5657 20130101;
B60N 2/5614 20130101; B60N 2/5692 20130101 |
Class at
Publication: |
62/3.61 |
International
Class: |
F25B 21/04 20060101
F25B021/04 |
Claims
1. Apparatus for improving the energy efficiency of a motor vehicle
having a drivetrain temperature control loop carrying a
heat-exchange fluid to a drivetrain component, the apparatus
comprising: a thermoelectric heat-pump disposed in the vehicle ;
and a comfort control loop exchanging heat with the thermoelectric
heat-pump and with the drivetrain temperature control loop.
2. The apparatus of claim 1 wherein the comfort control loop
branches from the drivetrain loop and carries a portion of the
heat-exchange fluid.
3. The apparatus of claim 2 wherein the portion of the fluid
carried by the comfort control loop is regulated by at least one
valve.
4. The apparatus of claim 3 wherein the at least one valve is
controlled at least in part by an automatic climate control
system.
5. The apparatus of claim 1 wherein the comfort control loop
carries a second heat-exchange fluid that exchanges heat with the
heat-exchange fluid of the drivetrain loop.
6. The apparatus of claim 5 wherein the comfort control loop and
the drivetrain loop exchange heat in a heat exchanger.
7. The apparatus of claim 1 wherein the drivetrain component is at
least one of a battery, a fuel cell, an electric motor, a power
electronics unit, and a mechanical transmission.
8. The apparatus of claim 1 wherein the thermoelectric heat-pump is
located in a passenger seat.
9. The apparatus of claim 1 wherein the drivetrain temperature
control loop comprises a heat exchanger through which the
heat-exchange fluid flows.
10. The apparatus of claim 9 wherein the heat exchanger is a second
thermoelectric heat-pump.
11. A system for improving the energy efficiency of a motor vehicle
comprising: a drivetrain component; a temperature control loop
circulating a heat-exchange fluid to the drivetrain component; a
thermoelectric heat-pump disposed in a passenger compartment of the
vehicle; and a comfort control loop branching from the temperature
control loop and carrying a portion of the heat-exchange fluid to
the thermoelectric heat-pump.
12. The system of claim 11 wherein the drivetrain component is at
least one of a battery, a fuel cell, an electric motor, a power
electronics unit, and a mechanical transmission.
13. The system of claim 11 wherein the portion of the fluid carried
by the comfort control loop is regulated by a valve.
14. The system of claim 13 wherein the valve is controlled by an
automatic climate control system.
15. The system of claim 11 wherein thermoelectric heat-pump is
located in a passenger seat.
16. The system of claim 11 wherein the temperature control loop
comprises a heat exchanger through which the heat-exchange fluid
flows.
17. The system of claim 16 wherein the heat exchanger is a second
thermoelectric heat-pump.
18. Apparatus for improving the energy efficiency of a motor
vehicle comprising: a drivetrain component; a temperature control
loop circulating a heat-exchange fluid to the drivetrain component
and including a drivetrain heat exchanger; a thermoelectric
heat-pump disposed in a passenger compartment of the vehicle; and a
comfort control loop exchanging heat with the drivetrain
temperature control loop and with the thermoelectric heat-pump.
19. The apparatus of claim 18 further comprising: a HVAC system
circulating air through the passenger compartment; and an
electronic control unit controlling the HVAC system and the
thermoelectric heat-pump.
20. The apparatus of claim 18 wherein the comfort control loop
branches from the drivetrain temperature control loop and carries a
portion of the heat-exchange fluid.
Description
TECHNICAL FIELD
[0001] The present invention relates to a comfort control system
for a vehicle that includes a thermoelectric heat pump (Peltier
device) having a fluid temperature control loop, and specifically
to such a system in which energy efficiency is improved by the
exchange of heat energy between the temperature control loop and a
second fluid temperature control loop that controls the temperature
of a drivetrain component.
BACKGROUND
[0002] Electric powered vehicles (including hybrid-electric
vehicles, fuel cell vehicles, plug-in electric vehicles, etc.) have
one or more drivetrain components that should be maintained within
a desired operating temperature range for optimum performance.
Examples of such drivetrain components are high-voltage batteries,
electric machines (motors, generators, and/or combined devices),
and transmissions. Under some operating conditions, a temperature
control system is necessary to cool and/or heat the components to
maintain them within the desired temperature range.
[0003] It is known to provide a temperature control system in which
a fluid (usually a liquid) is circulated to, through, or around the
drivetrain component where the fluid removes (or adds) heat energy,
and through a heat exchanger to reject (or absorb) heat energy to
some other medium, usually ambient air. In this context, the term
"heat exchanger" refers to any apparatus that may achieve the
desired result of adding and/or removing heat to/from the fluid
circulating in the control system. This heat exchange function may
be performed by apparatus such as a fluid/fluid heat exchanger, a
refrigerant-cycle heat pump, and a thermoelectric heat pump (also
known as a Peltier device).
[0004] Thermoelectric heat pumps are currently used in some
automotive vehicles to cool and/or heat a storage compartment in
order to store food or drinks at a desired temperature. It is also
known to use thermoelectric heat pumps to heat and/or cool seats in
the vehicle interior. In such "air conditioned seats," the seating
surface which contacts the seat occupant is typically perforated
and a fan circulates air over the cold side of the Peltier cooler
and blows the cooled or heated air out of the perforations in the
seat skin.
[0005] It has also been proposed to integrate a liquid heat
exchanger with a thermoelectric heat pump. In this concept, a
liquid working fluid passes through the heat pump. In heating mode,
heat is pumped from the working fluid through the thermoelectric
device into the passenger comfort air. In cooling mode, heat is
rejected from the air into the liquid working fluid.
SUMMARY
[0006] The object of the invention is to improve the overall energy
efficiency of a motor vehicle, in particular an electric vehicle,
by reducing or eliminating the need to use electric power to run a
conventional heater or air conditioning unit to achieve a
comfortable cabin temperature.
[0007] According to a feature disclosed herein, an interior
temperature control apparatus for a motor vehicle having a
temperature control loop carrying a heat-exchange fluid to a
drivetrain component comprises a thermoelectric heat-pump disposed
in the vehicle, and a comfort control loop exchanges heat with the
thermoelectric heat-pump and with the drivetrain temperature
control loop. This increases the net amount of heating or cooling
that can be delivered to the desired location by the thermoelectric
heat-pump, thereby reducing the amount of electrical power that may
otherwise be needed to run the climate control system.
[0008] According to another feature disclosed herein, the comfort
control loop branches from the drivetrain loop and carries a
portion of the heat-exchange fluid carried in the drivetrain
loop.
[0009] According to another feature disclosed herein, the comfort
control loop carries a second heat-exchange fluid that exchanges
heat with the heat-exchange fluid of the drivetrain loop.
[0010] According to another feature disclosed herein, an apparatus
for passenger comfort control in a motor vehicle comprises a
drivetrain component, a temperature control loop circulating a
heat-exchange fluid to the drivetrain component, a thermoelectric
heat-pump disposed in a passenger compartment of the vehicle, and a
comfort control loop branching from the temperature control loop
and carrying a portion of the heat-exchange fluid to the
thermoelectric heat-pump.
[0011] According to another feature disclosed herein, the passenger
comfort control apparatus further comprises a HVAC system
circulating air through the passenger compartment, and an
electronic control unit controlling the HVAC system and the
thermoelectric heat-pump. Integrating the control of the
thermoelectric heat pump with the HVAC system achieves optimum
energy management, thereby minimizing energy usage while
maintaining a comfortable passenger environment.
BRIEF DESCRIPTION OF THE DRAWINGS
[0012] FIG. 1 is a schematic system diagram of a thermoelectric
comfort control system according to a first disclosed
embodiment;
[0013] FIG. 2A is a schematic depiction of a thermoelectric heat
pump with fluid a heat exchange fluid loop;
[0014] FIG. 2B is a schematic depiction of a Peltier element of the
type used in a thermoelectric heat pump; and
[0015] FIG. 3 is schematic system diagram of second embodiment of a
thermoelectric comfort control system.
DETAILED DESCRIPTION
[0016] As required, detailed embodiments of the present invention
are disclosed herein; however, it is to be understood that the
disclosed embodiments are merely exemplary of the invention that
may be embodied in various and alternative forms. The figures are
not necessarily to scale; some features may be exaggerated or
minimized to show details of particular components. Therefore,
specific structural and functional details disclosed herein are not
to be interpreted as limiting, but merely as a representative basis
for teaching one skilled in the art to variously employ the present
invention.
[0017] Referring to FIG. 1, a thermoelectric comfort control system
for a vehicle includes one or more thermoelectric heat pumps 10
located in, on, or adjacent to a passenger compartment of a
vehicle. In the depicted embodiment, thermoelectric heat pumps
(TEHP) are located inside a passenger seat 12, one in the seat
bottom and one in the seat back. TEHPs may be provided at other
locations within a passenger cabin where heating and/or cooling is
required, such as beneath a seat, adjacent a foot-well area, behind
a body trim panel (e.g., headliner or door trim), or behind the
instrument panel. Further, TEHPs may be located within or adjacent
to a storage compartment in order to heat and/or cool the storage
compartment as may be required, for example, to store food or
drinks at a desired temperature.
[0018] TEHPs as described herein operate on the well-known Peltier
effect in which a DC electric voltage is applied across pairs of
n-type and p-type thermo elements to cause an electron flow and
resulting heat transfer from a "cold side" to a "hot side" of the
elements. Reversing the polarity of the DC voltage reverses the
flow of electrons and results in a switching of the hot side and
cool side. Accordingly, a single TEHP may be used either as a
heating device or a cooling device by simply applying the
appropriate voltage polarity.
[0019] The following description primarily discusses the situation
where TEHPs 10 are used to cool the vehicle interior. This should,
however, not be construed to limit the scope of the present
invention since, as noted above, TEHPs 10 may easily be operated to
heat the vehicle interior if desired.
[0020] A comfort control loop 14 circulates a heat exchange fluid
through TEHPs 10. Comfort control loop 14 may comprise hollow pipes
or tubes that enter TEHPs and pass across one side of the Peltier
devices to allow an exchange of heat energy between the fluid and
the Peltier device, and exit the TEHP. In the embodiment depicted
in FIG. 1, comfort control loop 14 branches off from a drivetrain
temperature control loop 16 and carries a portion of the heat
exchange fluid circulating through the drivetrain temperature
control loop.
[0021] The amount or portion of heat exchange fluid that is
diverted from the drivetrain temperature control loop 16 to
circulate through comfort control loop 14 may be regulated by one
or more valves 18 that are preferably controlled by an electronic
control unit (ECU) 20, the operation of which will be further
described below. A pump 19 may be provided to provide additional
control over the amount and direction of the flow of fluid through
comfort control loop 14.
[0022] Drivetrain temperature control loop 16 exchanges heat energy
with one or more drivetrain components 22 and with a heat exchanger
24. In an electrically powered vehicle, drivetrain components 22
may comprise one or more components such as a high-voltage battery,
electric motors, generators, and power electronics (such as DC/DC
or AC/DC converters). Under most vehicle operating conditions, such
drivetrain components will generate excess heat when operating, so
that the heat exchange fluid circulating in drivetrain temperature
control loop 16 carries heat away from the components. Heat
exchanger 24 may comprise one or more of a conventional
liquid-to-liquid or liquid-to-air exchanger, a heat pump using a
fluid refrigerant cycle, or a thermoelectric (Peltier) heat pump.
In any event, the objective of drivetrain temperature control loop
16 and heat exchanger 24 is to heat or cool drivetrain component 22
as is necessary to maintain a desired operating temperature
range.
[0023] ECU 20 may receive signals or inputs from a variety of
sensors and controls. Examples of such sensors include: cabin
temperature sensor(s) 26; exterior temperature sensor(s) 28; and
sensor(s) 32 monitoring conditions of drivetrain components 22,
heat exchanger 24, or drivetrain temperature control loop 16.
Inputs may be made by a vehicle occupant using a climate control
panel 30. Such inputs may include desired temperature, fan speed,
direction of air flow, or simply "heat" or "cool." ECU 20 controls
the condition of valve(s) 18 and/or pump 19 to regulate the
direction and/or flow rate of heat exchange fluid to TEHPs 10. ECU
20 preferably also controls the electric voltage/current/polarity
applied to the Peltier elements within TEHPs 10. By monitoring
and/or controlling the basic parameters of the temperature and
volume flow rate of the heat exchange fluid traveling through
comfort control loop 14 and the voltage and polarity of the current
applied to the Peltier devices and TEHPs 10, ECU 20 controls the
amount or level of heating and/or cooling supplied to vehicle
interior and any occupants.
[0024] Heat transfer from/to TEHPs 10 may be enhanced by one or
more fans or other air movement devices (not shown) integrated with
or located adjacent to the TEHPs to circulate air over the
occupant/cabin side of the Peltier device. ECU 20 may also control
the on/off condition and/or the speed of the fans.
[0025] ECU 20 may also control other vehicle comfort control
systems, such as an HVAC system 36, and may have one or more
automatic climate control operating modes. HVAC system 36 comprises
apparatus for circulating heated, cooled, or otherwise conditioned
air through the vehicle interior, such as a conventional air
conditioning system and/or vehicle heater. Alternatively ECU 20 may
be connected with a separate control device (not shown) for HVAC
system 36 so that the two systems may operate in a coordinated
manner.
[0026] As shown schematically in FIG. 2A, a possible embodiment of
a TEHP 10 includes Peltier elements 50 arranged on opposite sides
of a multi-tube conduit 52. Conduit 52 is part of comfort control
loop 14 and conducts heat exchange fluid in a direction into/out of
the page. Fins 54 extend outwardly from Peltier elements 50 in both
directions (up and down, as viewed in FIG. 2A), and the entire
structure is contained in an air flow housing 56. A fan 48 (or
other air movement device) is positioned to force air (usually
ambient air from the passenger cabin or other interior compartment
of the vehicle) through air flow housing 56 and over fins 54. The
air flow exits TEHP 10 and passes into the portion of the vehicle
interior that is being warmed or cooled by the system.
[0027] FIG. 2B shows, again in schematic form, an example of a
Peltier element 50. Each Peltier element comprises a p-type element
50a and an n-type element 50b electrically connected with one
another and with a DC voltage source as shown. When the indicated
polarity is applied, the side of element 50 in contact with conduit
52 (see FIG. 2A) becomes the hot side and the opposite side, in
contact with fin 54, becomes the cold side.
[0028] On a warm day, when vehicle occupants are most likely to be
using TEHPs 10 in a cooling mode, heat energy from the hot side of
the Peltier elements passes to the heat exchange fluid in the
comfort control loop 14 as it circulates through the TEHPs. Thus,
the fluid carries heat out of the passenger compartment and travels
to/through heat exchanger 24 along with the rest of the heat
exchange fluid circulating through the drivetrain temperature
control loop 16. Also on such a warm day, drivetrain components 22
will usually generate excess heat that must be removed by the
drivetrain loop 16 in order to maintain the drive train components
within the desired operating temperature range. So heat exchanger
24 will be operating in a mode to cool the fluid circulating in
drivetrain loop 16. If heat exchanger 24 is a heat pump
(refrigerant cycle or Peltier), it will be operated in a cooling
mode, which is compatible with the need to cool the fluid reaching
the heat exchanger from the comfort control loop 14.
[0029] Under colder ambient conditions, vehicle occupants are
likely to be using TEHPs 10 in a heating mode, in which heat
exchange fluid circulating though comfort control loop 14 passes
over the cold side of the TEHPs. The fluid therefore exits TEHPs 10
cooler than when it entered and must gain heat energy before
returning to the TEHPs. Under all but very cold ambient conditions,
this need for heat energy will be met by the excess heat generated
by drivetrain components 22. Under very cold conditions, drivetrain
components 22 may need to be warmed by the drivetrain temperature
control loop 16 in order to stay within the desired operating
temperature range. In this case, heat exchanger 24 will operate in
a mode to warm the fluid circulating in drivetrain loop 16, and the
branching comfort control loop 14.
[0030] The direction in which the fluid flows through comfort
control loop 14 may be controlled (using a bi-directional pump 19
or any other appropriate means) as necessary to divert working
fluid from powertrain loop 16 at the location best suited for
operation of the system. The flow direction may depend on many
factors, such as ambient temperature, fluid temperatures,
drivetrain component temperatures, commanded function of the TEHP,
etc.
[0031] FIG. 3 shows a second embodiment of a thermoelectric heat
pump comfort control system in which heat is exchanged between the
comfort control loop 114 and the drivetrain temperature control
loop in a manner different from the embodiment of FIG. 1. In this
second embodiment, drivetrain components 122 are oil-cooled
components such as, for example, a mechanical transmission or an
electric machine (generator, motor, or integrated motor/generator).
The cooling oil is circulated through a primary drivetrain loop
116a to an oil-to-coolant heat exchanger 124a by a pump 23.
[0032] A secondary drivetrain cooling loop 116b contains a second
heat exchange fluid that circulates through oil-to-coolant heat
exchanger 124a and a second fluid-to-air heat exchanger 124b.
Comfort control loop 114 also passes through the oil-to-coolant
heat exchanger 124a under pressure provided by a pump 38 controlled
by ECU 20. The heat exchange fluid circulating in comfort control
loop 114 remains physically separate from both the primary and
secondary drivetrain control loops 116a and 116b and may exchange
heat with either or both of the fluids (oil and/or coolant) carried
in those loops, depending on the interior configuration of
oil-to-coolant heat exchanger 124a. In this second embodiment, as
with the first embodiment of FIG. 1, the comfort control loop
exchanges heat with the drivetrain temperature control loop in
order to increase the amount of heat that it is possible to
efficiently transfer into (or out of) the desired portion of the
vehicle cabin using thermoelectric heat pumps.
[0033] While exemplary embodiments are described above, it is not
intended that these embodiments describe all possible forms of the
invention. Rather, the words used in the specification are words of
description rather than limitation, and it is understood that
various changes may be made without departing from the spirit and
scope of the invention. Additionally, the features of various
implementing embodiments may be combined to form further
embodiments of the invention.
* * * * *