U.S. patent application number 13/485184 was filed with the patent office on 2013-12-05 for system and method for controlling power in a hybrid vehicle using cost analysis.
This patent application is currently assigned to Rockwell Collins Control Technologies, Inc.. The applicant listed for this patent is David W. VOS. Invention is credited to David W. VOS.
Application Number | 20130325214 13/485184 |
Document ID | / |
Family ID | 49671227 |
Filed Date | 2013-12-05 |
United States Patent
Application |
20130325214 |
Kind Code |
A1 |
VOS; David W. |
December 5, 2013 |
SYSTEM AND METHOD FOR CONTROLLING POWER IN A HYBRID VEHICLE USING
COST ANALYSIS
Abstract
A system for controlling power of a hybrid vehicle may include a
controller configured to receive a signal indicative of a commanded
acceleration for the hybrid vehicle and determine a potential for
each of a power source, a generator, and an energy storage device
to supply energy to achieve the commanded acceleration. The
controller may be further configured to determine a cost associated
with using each of the power source, the generator, and the energy
storage device to achieve the commanded acceleration, and determine
a combination of the power source, the generator, and the energy
storage device that achieves the commanded acceleration at a lowest
total cost. The controller may also be configured to provide a
signal to at least one of the power source, the generator, and the
energy storage device to achieve the commanded acceleration based
on the determined combination.
Inventors: |
VOS; David W.; (Delaplane,
VA) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
VOS; David W. |
Delaplane |
VA |
US |
|
|
Assignee: |
Rockwell Collins Control
Technologies, Inc.
|
Family ID: |
49671227 |
Appl. No.: |
13/485184 |
Filed: |
May 31, 2012 |
Current U.S.
Class: |
701/3 ;
180/65.28; 180/65.285; 180/65.29; 701/21; 701/22; 903/903 |
Current CPC
Class: |
B60W 2540/10 20130101;
B60W 2510/244 20130101; B60W 10/26 20130101; B60W 20/14 20160101;
Y02T 10/84 20130101; B60W 10/06 20130101; B60W 30/188 20130101;
B60W 20/00 20130101; B60W 10/08 20130101; Y02T 10/6286 20130101;
B60W 20/13 20160101; Y02T 10/62 20130101 |
Class at
Publication: |
701/3 ; 701/22;
701/21; 180/65.28; 180/65.285; 180/65.29; 903/903 |
International
Class: |
B60W 20/00 20060101
B60W020/00 |
Claims
1. A system for controlling power of a hybrid vehicle, the hybrid
vehicle comprising a power source, a generator, and an energy
storage device, the system comprising: a controller configured to:
receive a signal indicative of a commanded acceleration for the
hybrid vehicle; determine a potential for each of the power source,
the generator, and the energy storage device to supply energy to
achieve the commanded acceleration; determine a cost associated
with using cacti of the power source, the generator, and the energy
storage device to achieve the commanded acceleration; determine a
combination of the power source, the generator, and the energy
storage device that achieves the commanded acceleration at a lowest
total cost; and provide a signal to at least one of the power
source, the generator, and the energy storage device to achieve the
commanded acceleration based on the determined combination, wherein
the cost associated with use of the energy storage device to assist
with achieving the commanded acceleration is based on a first level
of energy stored in the energy storage device and an estimated
amount of time required to restore energy to the energy storage
device to the first level of stored energy if the energy of the
energy storage device is used to assist with achieving the
commanded acceleration.
2. The system of claim 1, wherein the cost associated with using
the power source to assist with achieving the commanded
acceleration comprises a cost associated with fuel consumption
resulting from operation of the power source to achieve the
commanded acceleration and a cost associated with undesirable
emissions resulting from operation of the power source to achieve
the commanded acceleration.
3. The system of claim 1, wherein the cost associated with using
the generator to assist with achieving the commanded acceleration
comprises a cost associated with fuel consumption resulting from
operation of the power source to operate the generator to achieve
the commanded acceleration and a cost associated with undesirable
emissions resulting from operation of the power source to operate
the generator to achieve the commanded acceleration.
4. (canceled)
5. The system of claim 1, wherein the power source comprises at
least one internal combustion engine.
6. The system of claim 1, wherein the energy storage device
comprises at least one of a battery, a capacitor, and a
flywheel.
7. A hybrid vehicle comprising: at least one propulsion member; a
power source configured to supply energy to the hybrid vehicle; a
generator operably coupled to at least one of the power source and
the propulsion member; an energy storage device; a transmission
operably coupled to the at least one propulsion member, the
transmission being configured to receive energy from at least one
of the power source, the generator, and the energy storage device,
and provide torque to the at least one propulsion member; and a
controller configured to: receive a signal indicative of a
commanded acceleration for the hybrid vehicle; determine a
potential for each of the power source, the generator, and the
energy storage device to supply energy to achieve the commanded
acceleration; determine a cost associated with using each of the
power source, the generator, and the energy storage device to
achieve the commanded acceleration; determine a combination of the
power source, the generator, and the energy storage device that
achieves the commanded acceleration at a lowest total cost; and
provide a signal to at least one of the power source, the
generator, and the energy storage device to achieve the commanded
acceleration based on the determined combination, wherein the cost
associated with use of the energy storage device to assist with
achieving the commanded acceleration is based on a first level of
energy stored in the energy storage device and an estimated amount
of time required to restore energy to the energy storage device to
the first level of stored energy if the energy of the energy
storage device is used to assist with achieving the commanded
acceleration.
8. The hybrid vehicle of claim 7, wherein the at least one
propulsion member comprises one of a wheel, a propeller, and a
fan.
9. The hybrid vehicle of claim 7, wherein the transmission
comprises a continuously-variable transmission.
10. The hybrid vehicle of claim 7, wherein the transmission
comprises an electric motor.
11. The hybrid vehicle of claim 7, wherein the hybrid vehicle
comprises one of a car, a truck, a train, a boat, and an
airplane.
12. The hybrid vehicle of claim 7, wherein the cost associated with
using the power source to assist with achieving the commanded
acceleration comprises a cost associated with fuel consumption
resulting from operation of the power source to achieve the
commanded acceleration and a cost associated with undesirable
emissions resulting from operation of the power source to achieve
the commanded acceleration.
13. The hybrid vehicle of claim 7, wherein the cost associated with
using the generator to assist with achieving the commanded
acceleration comprises a cost associated with fuel consumption
resulting from operation of the power source to operate the
generator to achieve the commanded acceleration and a cost
associated with undesirable emissions resulting from operation of
the power source to operate the generator to achieve the commanded
acceleration.
14. (canceled)
15. The hybrid vehicle of claim 7, wherein the power source
comprises at least one internal combustion engine.
16. The hybrid vehicle of claim 7, wherein the energy storage
device comprises at least one of a battery, a capacitor, and a
flywheel.
17. A computer-implemented method for controlling the power of a
hybrid vehicle comprising a power source, a generator, and an
energy storage device, the method comprising: receiving by a
processor a signal indicative et a commanded acceleration for the
hybrid vehicle; determining by the processor a potential for each
of the power source, the generator, and the energy storage device
to supply energy to achieve the commanded acceleration; determining
by the processor a cost associated with using each of the power
source, the generator, and the energy storage device to achieve the
commanded acceleration; determining by the processor a combination
of the power source, the generator, and the energy storage device
that achieves the commanded acceleration at a lowest total cost;
and providing by the processor a signal to at least one of the
power source, the generator, and the energy storage device to
achieve the commanded acceleration based on the determined
combination, wherein the cost associated with use of the energy
storage device to assist with achieving the commanded acceleration
is based on a first level of energy stored in the energy storage
device and an estimated amount of time required to restore energy
to the energy storage device to the first level of stored energy if
the energy of the energy storage device is used to assist with
achieving the commanded acceleration.
18. The method of claim 17, wherein the cost associated with using
the power source to assist with achieving the commanded
acceleration comprises a cost associated with fuel consumption
resulting from operation of the power source to achieve the
commanded acceleration and a cost associated with undesirable
emissions resulting from operation of the power source to achieve
the commanded acceleration.
19. The method of claim 17, wherein the cost associated with using
the generator to assist with achieving the commanded acceleration
comprises a cost associated with fuel consumption resulting from
operation of the power source to operate the generator to achieve
the commanded acceleration and a cost associated with undesirable
emissions resulting from operation of the power source to operate
the generator to achieve the commanded acceleration.
20. (canceled)
Description
FIELD OF THE DESCRIPTION
[0001] The present disclosure relates to systems and methods for
controlling power in a hybrid vehicle. In particular, the present
disclosure relates to systems and methods for controlling power in
a hybrid vehicle using a cost analysis.
BACKGROUND
[0002] In order to increase efficiency and reduce undesirable
emissions during operation of internal combustion engines, hybrid
vehicles have been developed in an attempt to recover energy
previously lost during operation of the vehicle. Such systems
typically operate by storing energy previously lost during
operation or deceleration of the vehicle. For example, such systems
may include braking systems that harness the kinetic energy lost as
the speed of the vehicle is reduced. For example, braking may be
accomplished at least in part using generators or flywheels to
reduced the speed of the vehicle. Energy previously lost during
deceleration, primarily in the form of heat, may be stored in
batteries, capacitors, and/or flywheels. Once stored, the energy
may be used to provide electric power to one or more electric
motors to assist with propelling the vehicle, for example, during
acceleration.
[0003] Although such systems are effective in improving efficiency
and reducing undesirable emissions during operation of a vehicle,
it would be desirable to provide a system and method for
controlling the manner in which the energy associated with a hybrid
vehicle is stored and consumed such that overall efficiency of the
hybrid vehicle is improved and/or the amount of undesirable
emissions is further reduced. The systems and methods described
herein may improve the efficiency and/or reduce undesirable
emissions associated with operation a hybrid vehicle.
SUMMARY
[0004] In the following description, exemplary embodiments will be
presented. It should be understood that the invention, in its
broadest sense, could be practiced without having one or more
features of the exemplary embodiments.
[0005] In one aspect, a system for controlling power of a hybrid
vehicle may include a controller configured to receive a signal
indicative of a commanded acceleration for the hybrid vehicle and
determine a potential for each of a power source, a generator, and
an energy storage device to supply energy to achieve the commanded
acceleration. The controller may be further configured to determine
a cost associated with using each of the power source, the
generator, and the energy storage device to achieve the commanded
acceleration, and determine a combination of the power source, the
generator, and the energy storage device that achieves the
commanded acceleration at a lowest total cost. The controller may
also be configured to provide a signal to at least one of the power
source, the generator, and the energy storage device to achieve the
commanded acceleration based on the determined combination.
[0006] According to another aspect, a hybrid vehicle may include at
least one propulsion member, a power source configured to supply
energy to the hybrid vehicle, and a generator operably coupled to
at least one of the power source and the propulsion member. The
hybrid vehicle may further include an energy storage device, and a
transmission operably coupled to the at least one propulsion
member, the transmission being configured to receive energy from at
least one of the power source, the generator, and the energy
storage device, and provide torque to the at least one propulsion
member. The hybrid vehicle may further include a controller
configured to receive a signal indicative of a commanded
acceleration for the hybrid vehicle and determine a potential for
each of the power source, the generator, and the energy storage
device to supply energy to achieve the commanded acceleration. The
controller may be further configured to determine a cost associated
with using each of the power source, the generator, and the energy
storage device to achieve the commanded acceleration, and determine
a combination of the power source, the generator, and the energy
storage device that achieves the commanded acceleration at a lowest
total cost. The controller may be further configured to provide a
signal to at least one of the power source, the generator, and the
energy storage device to achieve the commanded acceleration based
on the determined combination.
[0007] According to a further aspect, a computer-implemented method
for controlling power of a hybrid vehicle may include receiving by
a processor a signal indicative of a commanded acceleration for the
hybrid vehicle and determining by the processor a potential for
each of a power source, a generator, and an energy storage device
to supply energy to achieve the commanded acceleration. The method
may further include determining by the processor a cost associated
with using each of the power source, the generator, and the energy
storage device to achieve the commanded acceleration, and
determining by the processor a combination of the power source, the
generator, and the energy storage device that achieves the
commanded acceleration at a lowest total cost. The method may
further include providing by the processor a signal to at least one
of the power source, the generator, and the energy storage device
to achieve the commanded acceleration based on the determined
combination.
[0008] Aside from the structural and procedural arrangements set
forth above, the invention could include a number of other
arrangements such as those explained hereinafter. It is to be
understood that both the foregoing description and the following
description are exemplary only.
BRIEF DESCRIPTION OF THE DRAWINGS
[0009] The accompanying drawings are incorporated in and constitute
a part of this description. The drawings illustrate exemplary
embodiments and, together with the description, serve to explain
some principles of the invention. In the drawings,
[0010] FIG. 1 is a schematic block diagram of an exemplary
embodiment of a hybrid vehicle including an exemplary power
system;
[0011] FIG. 2 is a functional block diagram for the exemplary
embodiment shown in FIG. 1;
[0012] FIG. 3 is a functional block diagram for an exemplary method
for controlling power;
[0013] FIG. 4 is a flowchart for an exemplary method for
controlling power; and
[0014] FIG. 5 is a schematic block diagram of another exemplary
embodiment of a hybrid vehicle including an exemplary power
system.
DESCRIPTION OF EXEMPLARY EMBODIMENTS
[0015] Reference will now be made in detail to exemplary
embodiments of the invention. Wherever possible, the same reference
numbers are used in the drawings and the description to refer to
the same or like parts.
[0016] FIG. 1 depicts an exemplary embodiment of a hybrid vehicle
10 including an exemplary hybrid power system 12 for supplying
power to one or more propulsion members 14 (e.g., one or more
wheels, propellers, and/or fans) configured to propel the hybrid
vehicle 10 and/or provide power to various electrically-powered
components of the hybrid vehicle 10. The hybrid vehicle 10 may be a
water-borne vehicle including submarines, ships, and boats; a
ground vehicle including cars and trucks; a rail vehicle including
trains; an air vehicle; and a space vehicle. The vehicle 10 may be
a manned or unmanned vehicle.
[0017] The exemplary power system 12 includes a power source 16
configured to convert potential energy into mechanical power. For
example, the power source 16 may be configured to convert potential
energy supplied by fuel into rotational power. Power source 16 may
be an internal combustion engine, such as, for example, a
two-stroke engine, a four-stroke engine, a spark-ignition engine, a
compression-ignition engine, a rotary engine, or a gas turbine
engine. The internal combustion engine may be configured to combust
fuel, such as, for example, gasoline, diesel fuel, bio-diesel,
methanol, ethanol, natural gas, kerosene, aviation fuel, jet fuel,
fuel oil, and/or combinations thereof (e.g., E85 (i.e., a blend of
15% gasoline and 85% ethanol)). According to some embodiments,
additional power sources may be included, such as solar-power
and/or power from a fuel-cell.
[0018] The power source 16 may be operably coupled to a generator
18 configured to convert mechanical power supplied by the power
source 16 into electric power. For example, the power source 16 may
be operably coupled to generator 18 via a transmission 20. The
transmission 20 may be configured to provide a coupling between the
power source 16 and the generator 18 that results in a constant
ratio of input speed to output speed, or the transmission 20 may be
configured to provide differing ratios of input speed to output
speed. For example, the transmission 20 may include a gear box,
which may be selectively operated such that the ratio of the speed
of the power source 16's output to the generator 18's input may be
changed. According to some embodiments, the transmission 20 may
provide discrete ratios by operating such that different
combinations of gears engage one another. According to some
embodiments, the transmission 20 may be a continuously-variable
transmission.
[0019] The exemplary power system 12 may include a transmission
servo 22 configured to change the effective gear ratio of the
transmission 20, so that speed of the generator 18 may be changed
relative to the speed of the power source 16. For example, the
power system 12 may be operated such that the power source 16
operates at a speed and torque and/or such that the generator 18
may be operated at a speed such that the efficiency of the power
system 12 is improved or optimized. The speed and/or torque of the
operation of the power source 16 may be selected such that the
power source 16's efficiency is improved or optimized based on, for
example, ambient air conditions. Further, the generator 18's speed
of operation may be optimized based on, for example, the amount of
power load placed on the power system 12. For example, the
efficiency of the power system 12 may be improved or optimized by
monitoring environmental conditions and selecting set-points for
controlling the power source 16's speed and/or the generator 18's
output based on known performance responses of the power system
12.
[0020] According to the exemplary embodiment depicted in FIG. 1,
the power source 16 includes an intake manifold 24 and an exhaust
manifold 26. The exhaust manifold 26 may be in flow communication
with a conduit 28 configured to provide a path for gases generated
during the combustion process to be evacuated from the power source
16 to the surroundings. According to some embodiments, the exhaust
manifold 26 may be in flow communication with a conduit configured
to supply at least a portion of the gases generated during the
combustion process to one or more turbochargers (not shown). The
turbocharger(s) may be configured to increase the manifold air
pressure (MAP) of the power source 16. The exhaust manifold 26 may
be in flow communication with a wastegate valve 30 configured to
control the portion of exhaust gases that flow to the
turbocharger(s) via conduit 32 instead of to the surroundings via
conduit 28. According to some embodiments, operation of the
wastegate valve 30 may be controlled via a wastegate servo 34, such
that the portion of the exhaust gases flowing via conduit 28 to the
surroundings may be changed, which, in turn, controls the portion
of the exhaust gases supplied to the turbocharger(s). For example,
the wastegate servo 34 may be configured to control the position of
the wastegate valve 30 in response to feedback from a measured
intake manifold air pressure (MAP).
[0021] According to some exemplary embodiments, a movable throttle
valve 36 may be associated with the intake manifold 24, as depicted
in FIG. 1. The throttle valve 36 may be controlled via, for
example, a throttle servo 38. The power system 12 may include a
manifold air pressure (MAP) sensor 40 configured generate a signal
indicative of the intake MAP.
[0022] According to some embodiments of the hybrid vehicle 10, the
generator 18 may be operably coupled to a drive-line transmission
42, and the power source 16 supplies the generator 18 with
mechanical power. According to some embodiments, the power source
16 is not coupled to the drive-line transmission 42 such that
mechanical power is supplied to the drive-line transmission 42.
Rather, the power source 16 provides mechanical power solely to the
generator 18. This type of arrangement is sometimes referred to as
a "series hybrid" configuration.
[0023] According to some embodiments, the drive-line transmission
42 may be a continuously-variable transmission, which includes one
or more electric motors operably coupled to the generator 18 and
the propulsion member(s) 14 of the hybrid vehicle 10. For example,
the drive-line transmission 42 may include an electric motor (not
shown) operably coupled to a differential and drive shafts (not
shown), which in turn, are operably coupled to the propulsion
member(s) 14. According to some embodiments, the drive-line
transmission 42 may include two or more electric motors, each
operably coupled to a propulsion member 14 of the hybrid vehicle
10. According to some embodiments, the drive-line transmission 42
may include one or more electric motors (not shown) operably
coupled a gear box (not shown) configured to provide differing
ratios between the speed of the electric motor output shaft(s) and
the input shaft of the gear box. The gear box may be operably
coupled to one or more propulsion members 14 of the hybrid vehicle
10 (e.g., via a differential and drive shaft(s)). According to some
embodiments, the gear box of the drive-line transmission 42 may
provide discrete gear ratios by engaging different combinations of
gears. According to these embodiments, the one or more electric
motors may be operated, for example, at a relatively constant
speed, and the hybrid vehicle 110 may be operated at different
speeds via changing the effective gear ratio of the gear box, which
may be a continuously-variable transmission.
[0024] According to some embodiments, the hybrid vehicle 10 may
include one or more energy storage devices 44, such as one or more
batteries, capacitors, and/or flywheels. For example, the energy
storage devices 44 may be configured to store excess electric
energy generated by the generator 18 and/or kinetic energy (i.e.,
via a flywheel). The stored energy may be used, for example, by
electric motor(s) of the drive-line transmission 42, for example,
when more electric power is desired for propelling the hybrid
vehicle 10 and/or to improve or optimize efficiency of the power
system 12 of the hybrid vehicle 10.
[0025] The power system 12 may include a drive-line transmission
servo 46 configured to change the effective gear ratio of the gear
box of the drive-line transmission 42. For example, the power
system 12 may be operated such that the power source 16 operates at
a speed and torque and/or such that the gear box of the drive-line
transmission 42 provides an effective gear ratio for improving
and/or optimizing the efficiency of the power system 12 at a
desired power output and/or vehicle speed. The speed and/or torque
of the operation of the power source 16 may be selected such that
the power source 16's efficiency is improved and/or optimized based
on, for example, ambient air conditions. Further, the drive-line
transmission 42's effective gear ratio may be optimized based on,
for example, the amount of power load placed on the power system
12. For example, the efficiency of the power system 12 may be
improved or optimized by monitoring environmental conditions and
selecting set-points for controlling the power source 16's speed
and/or the drive-line transmission 42's effective gear ratio based
on known performance responses of the power system 12.
[0026] The exemplary hybrid vehicle 10 shown in FIG. 1 includes a
control apparatus 48 more generally referred to as a controller.
The control apparatus 48 may include a processor 50 configured to
receive signals indicative of an operator's commanded power output
67 (see FIG. 2) for the hybrid vehicle 10, signals indicative of
environmental conditions (e.g., ambient air conditions), and
signals indicative of various parameters associated with the
components of the hybrid vehicle 10's power system 12. Based on
these signals, the processor 50 may determine one or more control
settings for the components of the power system 12 for improving or
optimizing the efficiency of the hybrid vehicle 10 and power system
12.
[0027] According to some embodiments, the processor 50 may include
a full authority digital electronic control (FADEC). For example,
the processor 50 may include a central processing unit (CPU) 52,
read only memory (ROM) 54, and/or random access memory (RAM) 56.
According to some embodiments, the processor 50 may be a 16-bit
micro-processor based on, for example, an INTEL microprocessor
(e.g., a microprocessor used in previous generations of FORD engine
electronic control units). The FADEC may be configured to meter
fuel and control fuel injection, for example, via a speed-density
method, and the FADEC may include a distributorless electronic
ignition having a double-fire capacity. According to some
embodiments, the processor 50 may be housed within a sealed
enclosure and/or may be cooled via air and/or liquid cooling, for
example, for high altitude applications.
[0028] The exemplary processor 50 of the hybrid vehicle 10 may
include one or more memories on which is stored executable
instructions that implement methods of power control or other
hardware that implements physical logic for controlling power
(generally referred to as "control logic"). For example, the
processor 50 may determine control settings for the components of
the power system 12, such as, for example, the power source 16, the
generator 18, the transmission servo 22, the energy storage device
44, the drive-line transmission 42 (including the one or more
electric motors and gear box), the drive-line transmission servo
46, the turbocharger(s), the wastegate valve 30, the wastegate
servo 34, the throttle valve 36, the throttle servo 38, the
ignition, the air-fuel mixture, the fuel injection timing and/or
the amount of fuel injected, and/or the timing and/or duration of
the opening and closing of the intake valves and/or exhaust valves
of the power source 16. Furthermore, the control process logic may
be implemented with digital information stored in computer software
and/or hardware incorporated into the processor 50. The processor
50 may be configured to receive signals indicative environmental
conditions, signals indicative of operating parameters associated
with the components of the power system 12, and signals indicative
of the commanded power output 67 (see FIG. 2) of the power system
12. Based on these signals, the processor 50 may control power of
the hybrid vehicle and output control settings for the components
of the power system 12, for example, at the end of each control
cycle.
[0029] The processor 50 may be configured to receive information
relating to the environmental conditions present during operation
of the power system 12. For example, the processor 50 may receive
signals indicative of the ambient air conditions, such as, for
example, the wind velocity, the humidity 58, the static and/or
dynamic air pressure 60, and/or the air temperature 62. The
processor 50 may also be configured to receive information relating
to the operation of the power source 16. For example, the processor
50 may receive signals from various sensors related to the
operating parameters associated with the power source 16, such as,
for example, signals indicative of an engine speed from an engine
speed sensor 64 and/or the MAP from the MAP sensor 40. According to
some embodiments, the processor 50 may be configured to receive
signals indicative of exhaust gas temperature (EGT), cylinder head
temperature (CHT), universal exhaust gas oxygen (UEGO), air charge
temperature (ACT), mass airflow (MAF), and/or exhaust pressure
(PEXH). The processor 50 may be configured to receive a signal
indicative of a commanded power output 67 for the power system 12
via, for example, an input device 66 and a communication link 68
(hard-wired or wireless). The above-mentioned signal(s) may be
received by processor 50 via a bus 70, for example, as shown in
FIG. 1, and/or via wireless transmission. According to some
embodiments, these signals may include, for example, analog
signals, which may range between about -10 volts and about +10
volts (e.g., between about -5 volts and about 5 volts), and/or
these signals may be in the form of digital signals.
[0030] According to some exemplary embodiments, the processor 50 is
configured to receive one or more of the above-mentioned signals
and provide control signals to one or more of the throttle servo
36, the transmission servo 22, and the wastegate servo 34. For
example, the CPU 52 may provide control signals to one or more of
the throttle servo 36, the transmission servo 22, and the wastegate
servo 34, as depicted in FIG. 1.
[0031] According to some exemplary embodiments, the processor 50
may also be configured to provide control signals to control, for
example, the turbocharger(s), the ignition timing (e.g., the spark
timing for a spark ignition engine), the air-fuel mixture, the fuel
injection timing and/or the amount of fuel injected, and/or the
timing and/or duration of the opening and closing of the intake
valves and/or exhaust valves of the power source 16. The control
signals may be carried via a bus 72 and/or via a wireless link.
According to some embodiments, the control signals may be in the
form of analog signals ranging from about 0 volts to about 5 volts,
and/or the control signals may be in the form of digital
signals.
[0032] The exemplary power system 12 may include a display 74
operably coupled to the processor 50, and the display 74 may be
configured to display information relating to the operation of the
power system 12, such as, for example, a desired MAP setting and/or
a desired generator speed setting. For example, according to some
embodiments, the processor 50 may determine settings for improving
or optimizing the efficiency of the power system 12, and the
processor 50 may display to an operator one or more of those
settings via the display 74. For example, the display 74 may
display an MAP setting, a generator speed setting, and/or a
throttle servo setting. The operator may be provided with controls
that enable the operator to manually supply control signals to one
or more of the various controllable components of the power system
12, such that one or more of the processor-determined settings may
be achieved. According to some embodiments, for example, as
outlined previously, the processor 50 may automatically supply
control signals to one or more of the various controllable
components of the power system 12, such that one or more of the
processor-determined settings may be achieved.
[0033] FIG. 2 is a block diagram showing the function of an
exemplary embodiment of the power system 12. In the exemplary
embodiment, the processor 50 receives signals indicative of
detected environmental conditions along with a signal indicative of
a commanded power output 67 (see FIG. 2) of the power system 12.
For example, the detected environmental conditions may be detected
via one or more air data sensors 76, and the commanded power output
67 may be received from the input device 66 (see FIG. 1). These
signals may be received by, for example, a FADEC of the processor
50. Upon receipt of these signals, the processor 50 may use a
process implemented with instructions and/or hardware logic to
access one or more look-up tables and/or maps stored in the ROM 54
and/or RAM 56. The look-up tables and/or maps may provide control
settings, for example, a power source speed command, an MAP
command, and/or a generator speed command, which may result in
improved or optimized efficiency of the power output of the power
system 12 based at least partially on the signals indicative of
detected environmental conditions and/or the commanded power output
67. Instead of (or in addition to) look-up tables and/or maps, the
processor 50 may determine the control settings via real-time
calculations via mathematical relationships, such as theoretically
and/or empirically-derived equations, which may be accessed by the
processor 50.
[0034] According to some embodiments, the control process
instructions or logic, the look-up tables, maps, and/or
mathematical equations may be supplied or coupled to the processor
50 via one or more digital storage devices, such as disks, memory
cards, memory sticks, and/or flash drives. According to some
embodiments, the control process instructions or logic, look-up
tables, maps, and/or mathematical equations may be provided via a
separate computer, for example, via a physical link and/or wireless
link. According to some embodiments, the computer may provide an
operator with advisory messages in addition to or in lieu of
providing control signals to the power system 12 to activate the
control servos and other controllable components of the power
system 12.
[0035] According to the exemplary embodiment depicted in FIG. 2,
the power system 12 (i.e., the processor 50) monitors signals
received from the air data sensors 76. The signals may be supplied
to one or more control algorithms 80, which may be configured to
determine a combination of the power source 16's operating speed,
the power source 16's power output or load setting, and/or the
generator 18's operating speed to improve or optimize the power
output efficiency of the power system 12. For example, the power
source 16's operating speed, the power source 16's power output or
load setting, and/or the generator 18's operating speed may be
determined such that the maximum efficiency of the combined power
source 16 and generator 18 is achieved for the detected
environmental conditions.
[0036] During operation according to some embodiments, an operator
of the power system 12 supplies a commanded power output 67 via
operation of the input device 66 (see FIG. 1). The control logic
(e.g., subroutine(s) running in the FADEC) receives the commanded
power output 67 and generate a signal indicative of an MAP
set-point, which, in turn, is received by a power source controller
82. The power source controller 82, according to some embodiments,
supplies a signal that serves to operate the throttle servo 38
and/or the wastegate servo 34 (see FIG. 1) to achieve an inlet MAP
corresponding to the operator's commanded power output 67.
According to some embodiments, the power source 16 does not include
a turbocharger, the power source controller 82 transmits a signal
that serves to operate the throttle servo 38 alone to achieve an
inlet MAP corresponding to the operator's commanded power output
67. The control logic of the control process 80 may also be
configured to output a generator speed set-point, which may be
received by a generator speed controller 84. The generator speed
controller 84 may be configured to operate the transmission servo
22 such that the transmission 20 provides a gear ratio resulting in
a generator speed that substantially matches the generator speed
set-point. The operating speed of the generator 18 may be sensed
via a speed sensor 64 operably coupled to the transmission 20.
[0037] According to some exemplary embodiments, the control logic
80 may use signals from the input device 44 to determine the MAP
and engine speed that will improve or optimize efficiency of the
power output at the commanded power output 67 (e.g., via
interpolation of data found in look-up tables and/or maps stored in
the ROM 54 and/or RAM 56).
[0038] The power output and/or specific fuel consumption of the
power source 16 may be controlled by at least two primary
variables, such as, for example, MAP and engine speed. The power
output and specific fuel consumption of the power source 16 are
related to MAP and engine speed, and those relationships may be
determined via testing and/or may be predicted. The relationships
between power output, specific fuel consumption, MAP, and/or engine
speed may be incorporated into look-up tables and/or maps, and/or
may be characterized by mathematical equations. Operation of the
generator 18 may be characterized by a power coefficient and
efficiency in relation to advance ratio, which, in turn, are
functions of generator speed, density, and load on the generator.
The relationships between the generator 18's power coefficient,
efficiency, advance ratio, generator speed, density, and load may
be incorporated into look-up tables and/or maps, or may be
characterized by mathematical equations. According to some
embodiments, the processor 50 may include one or more algorithms
configured to improve or optimize the power system 12's efficiency
based on one or more of the relationships between the power source
16's power output, specific fuel consumption, MAP, and engine
speed, and/or one or more of the relationships between the
generator 18's power coefficient, efficiency, advance ratio,
generator speed, density, and load.
[0039] According to some embodiments, the processor 50 may output a
set of engine speed and MAP data, which correspond to the
environmental conditions and commanded power outputs. These data
may be stored in the processor 50 (e.g., in the FADEC) in look-up
table and/or map form. The data may be supplied directly from the
look-up tables and/or maps and/or may be interpolated to obtain
engine speed and/or MAP settings for rendering improved or optimum
efficiency of power source 16 corresponding to a given set of
environmental conditions and commanded power output.
[0040] As shown in FIG. 3, in order to improve the efficiency
and/or reduce undesirable emissions of the hybrid vehicle 10, a
controller 86 may be provided (e.g., including processor 50 and/or
other processors) and may be configured to implement a cost
analysis associated with achieving a commanded acceleration 78 of
the hybrid vehicle 10. According to some embodiments, the cost
analysis includes evaluating the commanded acceleration 78, the
energy sources available to meet the commanded acceleration 78, and
the cost associated with using each of the available energy sources
to meet the commanded acceleration 78. Based on the cost analysis,
the controller 86 determines which energy source, or combination of
energy sources, will be used to meet the commanded acceleration 78.
For example, the controller 86 will select the energy source or
combination thereof that meets the commanded acceleration 78 with
the least cost and controls operation of those energy sources
accordingly.
[0041] According to the exemplary embodiment shown in FIG. 1, the
power source 16, the generator 18, and the energy storage devices
44 are potential sources of energy for achieving a commanded
acceleration 78. Each of those energy sources has a potential level
of energy for achieving the commanded acceleration 78, either
individually or in combination with one or more other energy
sources.
[0042] The potential level of energy may be time dependent. For
example, if the power source 16 is an internal combustion engine,
at a given point in time, it may operating at an instantaneous
engine speed, with an instantaneous torque and power output.
Further, the engine has the potential to provide more power within
a given time period. Similarly, the generator 18 has at a given
point in time, the ability to provide an instantaneous level of
power output and a potential, based on operation of the power
source 16, to increase that power output within a given time
period. The energy storage devices 44 may include batteries,
capacitors, and/or flywheels, and those energy storage devices 44
also have at a given time period, the ability to supply a discrete
amount of energy to accelerate the hybrid vehicle 10 via one or
more electric motors. Thus, at any given point in time during which
a change in velocity of the hybrid vehicle may be commanded, the
power source 16, generator 18, and energy storage devices 44 each
have a potential ability to meet, or assist with meeting, the
commanded acceleration 78, either individually or in
combination.
[0043] As shown in FIGS. 3 and 4, the controller 86 may configured
at step 87 to receive the commanded acceleration 78 from the input
device 66, and at step 88 determine for each of the power source
16, the generator 18, and the energy storage devices 44 the
availability to contribute to meeting the commanded acceleration
78, and at step 89 determine a cost associated with respective uses
of those energy sources (cost.sub.PS, cost.sub.GEN, and
cost.sub.ESD) to meet the commanded acceleration 78. For example,
if the power source 16 is an internal combustion engine, costs
cost.sub.PS associated with its use to achieve the commanded
acceleration 78 may include fuel consumption and undesirable
emissions. In particular, costs associated with operation of an
internal combustion engine may include, for example, the cost of
fuel for providing the desired power output associated with
achieving the commanded acceleration 78, the reduction in the
amount of fuel remaining in a fuel tank, and costs associated with
undesirable emissions from operation of the internal combustion
engine at a desired power output. These costs may be attributed to
operation of the power source 16 to achieve the commanded
acceleration 78, and such costs may be stored in maps or look-up
tables, and/or calculated real-time according to one or more
mathematical formulas.
[0044] Similarly, operation of the generator 16 and/or use of the
energy storage devices 44 may be assigned respective costs
cost.sub.GEN and cost.sub.ESD for operation to meet the commanded
acceleration 78. For example, similar to the power source 16, the
operation of the generator 18 may be assigned costs corresponding
to fuel consumption to operate the generator and costs associated
with undesirable emissions associated therewith. The energy storage
devices 44 may be assigned costs cost.sub.ESD associated with the
loss of potential to provide energy if used. For example, if a
battery has a certain level of charge, use of a portion of that
level of charge may be considered a cost associated with use of the
battery. Similar costs may be associated with using capacitors
and/or flywheels to supply energy to meet the commanded
acceleration 78. These costs may be attributed to operation of the
generator 18 and/or the energy storage devices 44 to achieve the
commanded acceleration 78, and such costs may be stored in maps or
look-up tables, and/or calculated real-time according to one or
more mathematical formulas.
[0045] During operation, the controller 86 may be configured to
perform a cost analysis at step 90 upon receipt of a commanded
acceleration 78 from input device 66. For example, upon receipt of
the commanded acceleration 78, the controller 86 may determine the
ability at that time of the power source 16, the generator 18,
and/or the energy storage devices 44 to supply energy to meet the
commanded acceleration 78. The controller 86 may also determine the
cost associated with the use at that time of each of the power
source 16, the generator 18, and the energy storage devices 44.
Thereafter, the controller 86 may select one or a combination of
the power source 16, the generator 18, and the energy storages
devices 44 to meet the commanded acceleration 78 in the manner
results in the least cost according to the costs associated with
using the power source 16, the generator 18, and the energy storage
devices 44. Thereafter, the controller 86 may at step 91 output the
level of power to be supplied by each of the power source 16, the
generator 18, and the energy storage devices 44 (output.sub.PS,
output.sub.GEN, and output.sub.ESD).
[0046] According to some embodiments, the cost analysis may be
dependent on the level of commanded acceleration 78. For example,
if the commanded acceleration 78 is at a maximum level according to
the input device 66, the controller 86 may determine that energy
should be supplied at the maximum available rate from the power
source 16, the generator 18, and the energy storage devices 44.
However, when the commanded acceleration 78 is below the maximum
level according to the input device 66, the controller 50 may be
configured to select one or a combination of the power source 16,
the generator 18, and the energy storages devices 44 that will meet
the commanded acceleration 78 in the most cost-effective
manner.
[0047] According to some embodiments of the hybrid vehicle 10, for
example, as schematically-depicted in FIG. 5, the power source 16
may be operably coupled to the drive-line transmission 42 and the
generator 18 via mechanical links, such that the power source 16
may selectively supply mechanical power to each of the drive-line
transmission 42 and the generator 18. Such a configuration is
sometimes referred to as a "parallel hybrid" configuration. The
drive-line transmission 42 may include one or more electric motors
(not shown) and/or a gear box (not shown) in a similar manner as
described previously herein with reference the exemplary embodiment
of FIG. 1. According to some embodiments, the power source 16 and
the electric motor(s) may be configured to selectively operate
independent of one another and/or in a complimentary manner to
provide power to the drive-line transmission 42's gear box, such
that the hybrid vehicle 10 may be propelled via one or more
propulsion members 14, according to an operator's commanded
acceleration 78.
[0048] The exemplary hybrid vehicle 10 shown in FIG. 5 includes a
control apparatus 48 including a processor 50 configured to receive
signals indicative of an operator's commanded acceleration 78,
signals indicative of environmental conditions (e.g., ambient air
conditions), and/or signals indicative of various parameters
associated with the components of the power system 12. Based on
these signals, the processor 50 determines one or more control
settings for the components of the power system 12 for improving or
optimizing the efficiency of the hybrid vehicle 10's power system
12. For example, the hybrid vehicle 10 may include a processor 50
at least similar to the exemplary processor 50 described previously
herein.
[0049] Similar to the exemplary embodiment of power system 12 of
FIG. 1, the exemplary processor 50 of the hybrid vehicle 10 may
include one or more power controller algorithms as described
previously herein. For example, the processor 50 may determine
control settings for the components of the power system 12, such
as, for example, the power source 16, the generator 18, the
transmission servo 22, the energy storage device 44, the drive-line
transmission 42 (including the one or more electric motors and gear
box), the drive-line transmission servo 46, the turbocharger(s),
the wastegate valve 30, the wastegate servo 34, the throttle valve
36, the throttle servo 38, the ignition, the air-fuel mixture, the
fuel injection timing and/or the amount of fuel injected, and/or
the timing and/or duration of the opening and closing of the intake
valves and/or exhaust valves of the power source 16. Furthermore,
the control algorithm(s) may be in the form of digital information
stored in computer software and/or hardware incorporated into the
processor 50. The processor 50 may be configured to receive signals
indicative of environmental conditions, signals indicative of
operating parameters associated with the components of the power
system 12, and signals indicative of the commanded power output.
Based on these signals, the processor 50 performs the control
algorithm(s) and outputs control settings for the components of the
power system 12, for example, at the end of each control cycle.
Furthermore, the processor 50 may be configured to allocate
mechanical power between the generator 18 and the drive-line
transmission 42 such that the efficiency of the power system 12 is
improved or optimized.
[0050] In addition, in order to improve the efficiency and/or
reduce undesirable emissions of the hybrid vehicle 10, a controller
86 may be provided and configured to implement a cost analysis
similar to the cost analysis described with respect to the
exemplary embodiment shown in FIG. 1. For example, the cost
analysis may include evaluating the commanded acceleration 78, the
energy sources available to meet the commanded acceleration 78, and
the cost associated with using each of the available energy sources
to meet the commanded acceleration 78. Based on the cost analysis,
the controller 86 may determine which energy source, or combination
of energy sources, will be used to meet the commanded acceleration
78. For example, the controller 86 will select the energy source or
combination thereof that meets the commanded acceleration 78 with
the least cost and controls operation of those energy sources
accordingly.
[0051] It will be apparent to those skilled in the art that various
modifications and variations can be made to the structures and
methodology described herein. Thus, it should be understood that
the invention is not limited to the subject matter discussed in the
description. Rather, the present invention is intended to cover
modifications and variations.
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