U.S. patent application number 14/300946 was filed with the patent office on 2014-12-11 for independent throttle optimization in locomotive consist systems.
This patent application is currently assigned to Energy Conversions, Inc.. The applicant listed for this patent is Energy Conversions, Inc.. Invention is credited to David Cook.
Application Number | 20140365049 14/300946 |
Document ID | / |
Family ID | 52006131 |
Filed Date | 2014-12-11 |
United States Patent
Application |
20140365049 |
Kind Code |
A1 |
Cook; David |
December 11, 2014 |
INDEPENDENT THROTTLE OPTIMIZATION IN LOCOMOTIVE CONSIST SYSTEMS
Abstract
The present disclosure provides systems and methods for reducing
the total cost of fuel consumed by a locomotives, particularly a
locomotive consist including dual fuel locomotives. The systems and
methods include generating an alternative throttle settings with
the goal of consuming the highest ratio of low cost fuel over high
cost fuel instead of only a focus on consuming the least amount of
one fuel.
Inventors: |
Cook; David; (Fullerton,
CA) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Energy Conversions, Inc. |
Tacoma |
WA |
US |
|
|
Assignee: |
Energy Conversions, Inc.
|
Family ID: |
52006131 |
Appl. No.: |
14/300946 |
Filed: |
June 10, 2014 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
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61833429 |
Jun 10, 2013 |
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Current U.S.
Class: |
701/20 |
Current CPC
Class: |
B61C 5/00 20130101; Y02T
30/00 20130101; Y02T 30/10 20130101; B61C 17/12 20130101 |
Class at
Publication: |
701/20 |
International
Class: |
B61C 17/12 20060101
B61C017/12; B61C 5/00 20060101 B61C005/00 |
Claims
1. A locomotive consist system comprising: at least two
locomotives, wherein each locomotive includes a locomotive throttle
optimizer (LTO), wherein at least one locomotive includes an
alternate fuel type; wherein at least one LTO device is a master
LTO device in communication with every other LTO device, wherein
the master LTO device includes: a controller; and a memory coupled
to the controller, wherein the memory is configured to store
program instructions executable by the controller, wherein in
response to executing the program instructions, the controller is
configured to: receive an engineer throttle notch value
corresponding to a total power value; access a database including
locomotive information for each locomotive in the consist, wherein
the locomotive information includes a fuel type used in the
locomotive, a fuel consumption rate corresponding to each of a
plurality of throttle notch power levels, and a fuel consumption
priority parameter corresponding to each fuel type used in the
locomotive; generate an alternate throttle setting for each
locomotive, wherein the alternate throttle setting includes a
selected throttle notch power level, wherein the combination of
alternate throttle settings for the at least two locomotives
produces a generated total power that is equivalent to the received
total power value, wherein the alternate throttle setting is based
on the fuel consumption priority parameter; and communicate the
alternate throttle setting to each locomotive.
2. The system of claim 1 wherein the fuel consumption priority
parameter includes a fuel cost, wherein the controller is
configured to calculate for each throttle notch power level a fuel
consumption cost, wherein the alternate throttle setting is based
on minimizing the total fuel cost.
3. The system of claim 1 wherein the master LTO device receives a
signal from each LTO device indicating an operating mode for the
locomotive, wherein the operating mode is selected from a primary
fuel mode or a dual fuel mode.
4. The system of claim 1 wherein the master LTO is the LTO with the
most recent software update.
5. The system of claim 1 wherein at least one fuel type is diesel
fuel.
6. The system of claim 1 wherein at least one fuel type is natural
gas.
7. The system of claim 1 wherein at least one fuel type is a
mixture of an alternative fuel type and a second fuel type.
8. The system of claim 1 wherein at least one locomotive is a dual
fuel locomotive including a first fuel type and a second fuel type;
wherein the database includes a plurality of first fuel consumption
rates of the first fuel type and a plurality of second fuel
consumption rates of a second fuel type, wherein each first
consumption rate corresponds to a first fuel power value and a
first fuel cost and each second consumption rate correspond to a
second fuel power value and a second fuel cost, wherein a total
fuel cost is the sum of the first fuel cost and second fuel cost,
wherein the controller generates an alternate throttle setting for
the dual fuel locomotive including a selected first fuel
consumption rate of the first fuel type and a selected second fuel
consumption rate of the second fuel type, wherein the alternate
throttle setting for the dual fuel locomotive is based on
minimizing the total fuel cost.
9. The system of claim 8 wherein the first fuel cost and second
fuel cost are automatically and periodically updated to reflect the
market price of the first fuel and second fuel.
10. The system of claim 8 wherein the master LTO device receives a
signal from each LTO device indicating an amount of each fuel type
available within the locomotive, wherein at least one locomotive
includes an alternate fuel type, wherein the generated alternate
throttle setting for each locomotive is based on equalizing an
alternative fuel type consumption among the locomotives.
11. The system of claim 8 further comprising a single fuel
locomotive including a single fuel type and a single fuel LTO
device in communication with the single fuel locomotive, wherein
the single fuel LTO device is in communication with the controller,
wherein the database includes a plurality of single fuel
consumption rates for the single fuel type, wherein each single
fuel consumption rate corresponds to a single power value and a
single fuel cost, wherein the controller generates an alternate
throttle setting including a selected first fuel consumption rate
of the first fuel type, a selected second fuel consumption rate of
the second fuel type, and a selected single fuel consumption rate
of the single fuel type, wherein the received total power value is
equal to the sum of the first fuel power value of the selected
first fuel consumption rate, the second fuel power value of the
selected second fuel consumption rate, and the single fuel power
value of the selected single fuel consumption rate, wherein a total
fuel cost is the sum of the first fuel cost, second fuel cost, and
the single fuel cost, wherein the alternate throttle setting is
based on minimizing the total fuel cost.
12. A method for producing alternate throttle setting for at least
two locomotives in a consist, wherein each locomotive includes a
locomotive throttle optimizer (LTO), the method comprising:
receiving an engineer throttle notch value corresponding to a total
power value; accessing a database including locomotive information
for each locomotive in the consist, wherein the information
includes a fuel type used in the locomotive, a fuel consumption
rate corresponding to each of a plurality of throttle notch power
levels, and a fuel consumption priority parameter corresponding to
each fuel type used in the locomotive; generating an alternate
throttle setting for each locomotive, wherein the alternate
throttle setting includes a selected throttle notch power level,
wherein the combination of alternate throttle settings produces a
generated total power that is equivalent to the received total
power value, wherein the alternate throttle setting is based on the
fuel consumption priority parameter; and communicating the
alternate throttle setting to each locomotive.
13. The method of claim 12 wherein the fuel consumption priority
parameter includes a fuel cost, wherein the method includes
calculating for each throttle notch power level a fuel consumption
cost, wherein the alternate throttle setting is based on minimizing
the total fuel cost.
14. The method of claim 12 further including receiving a signal
from each LTO device indicating whether each LTO is operating in a
primary fuel mode or dual fuel mode.
15. The method of claim 12 wherein at least one fuel type is diesel
fuel.
16. The method of claim 12 wherein at least one fuel type is
natural gas.
17. The method of claim 12 wherein the at least one fuel type is a
mixture of an alternative fuel type and a second fuel type.
18. The method of claim 12 wherein at least one locomotive is a
dual fuel locomotive including a first fuel type and a second fuel
type; wherein the database includes a plurality of first fuel
consumption rates of the first fuel type and a plurality of second
fuel consumption rates of a second fuel type, wherein each first
consumption rate corresponds to a first fuel power value and a
first fuel cost and each second consumption rate correspond to a
second fuel power value and a second fuel cost, wherein a total
fuel cost is the sum of the first fuel cost and second fuel cost,
wherein the method includes generating an alternate throttle
setting for the dual fuel locomotive including a selected first
fuel consumption rate of the first fuel type and a selected second
fuel consumption rate of the second fuel type, wherein the
alternate throttle setting for the dual fuel locomotive is based on
minimizing the total fuel cost.
19. The method of claim 18 further including automatically and
periodically updating the first fuel cost and second fuel cost to
reflect the market price of the first fuel cost and second fuel
cost.
20. The method of claim 18 further including receiving a signal
from each LTO device indicating an amount of each fuel type
available within the locomotive, wherein at least one locomotive
includes an alternate fuel type, wherein the generated alternate
throttle setting for each locomotive is based on equalizing an
alternative fuel type consumption among the locomotives.
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application incorporates by reference and claims
priority to U.S. Provisional Application 61/833,429 filed on Jun.
10, 2013.
BACKGROUND OF THE INVENTION
[0002] The present subject matter relates generally to the railroad
field and more particularly to devices, systems and methods for
reducing the total cost of fuel consumed by a locomotives,
particularly a locomotive consist including dual fuel
locomotives.
[0003] A locomotive consist is a group of locomotives physically
coupled together and configured to act as a single unit from the
controls of a single locomotive in the consist. In the U.S., the
operation of multiple locomotives in this manner is often referred
to as multiple unit, or "MU", operation. In this mode the throttle
setting (also referred to as the throttle notch) in the lead
locomotive, which may not be the first locomotive in the consist,
controls the throttle setting or notch in all locomotives in the
consist. A locomotive throttle typically has eight notches and an
idle position. Thus, for example, in prior systems, if an operator
in a lead locomotive in an MU consist puts the throttle in notch 5
(approximately 50% power), then every other locomotive in the
consist will also operate at a notch 5 throttle setting (it should
be noted that the actual throttle may or may not move in each
locomotive, but that the control signals supplied to each
locomotive power plant will correspond to a notch 5 throttle
setting)
[0004] It has been recognized that the operation of all locomotives
in a consist in the same throttle setting is not always the most
fuel-efficient. Several prior art patents have taught ways to
optimize the throttle settings between locomotives in a consist to
achieve the same requested total power at a lower fuel consumption
rate.
[0005] U.S. Pat. No. 4,344,364 teaches a basic system that uses an
interface control box in each locomotive of a consist to
communicate with each other, calculate the optimum alternative
throttle settings for each locomotive, and implement these
alternative throttle settings. Hereinafter the interface control
box with its alternate throttle setting concept will be referred to
as a locomotive throttle optimizer (LTO).
[0006] U.S. Pat. No. 7,618,011 is directed to a consist manager
system that performs a similar function, and will even modulate the
throttle settings on trailing locomotives that don't have the
consist manager equipment installed. The important difference is
that this type of LTO system requires frequent operator interaction
where the train crew must manually input into the lead locomotive's
control system the makeup of the consist every time the consist
locomotive makeup is changed.
[0007] EMD has publically advertised as an option on its newer
locomotives a Smart Consist system that appears to perform similar
to U.S. Pat. No. 4,344,364. An LTO option is also advertised as an
optional feature for its aftermarket EM2000 control system for
older locomotives being rebuilt and upgraded.
[0008] U.S. Pat. No. 8,095,253 by Invensys teaches a more advanced
system than U.S. Pat. No. 4,344,364. This system incorporates more
information in an initialization communication string from each LTO
to the other LTO's in the consist. This additional information
includes a power and efficiency table for the particular locomotive
that the LTO is installed on. This allows the upgrading of the
power and efficiency information in one locomotive without having
to upgrade the data files in the other LTO systems in the
locomotive fleet. The entirety of U.S. Pat. No. 8,095,253 is hereby
incorporated by reference.
[0009] Prior to U.S. Pat. No. 8,095,253 Invensys offered for sale
and published an operating manual for an LTO system in which each
LTO would have an installed data base of all the possible
locomotives in the fleet that it could be connected to. When an LTO
is installed in a locomotive, the box is configured to know which
type of locomotive it is installed into by configuring some
switches internal to the LTO. With 8 DIP switches an LTO can be
installed on 256 different locomotive configurations. Upon
initialization a typical LTO will broadcast its serial number and
the locomotive configuration that it is attached to. Among the
LTO's, one unit is typically determined to be the master LTO and
the other LTO's become slave LTO's. Currently the master LTO is
determined by serial number, with the highest serial number
becoming the master LTO. It was the master LTO that performed the
calculations and instructed each slave LTO what throttle setting it
would operate at.
[0010] The improvement of U.S. Pat. No. 8,095,253 is not needed if
the internal LTO system programming is revised slightly. As part of
the initialization string, each interface unit can also broadcast
the revision level or date of its latest software and database
update. The LTO with the latest revision should become the master
LTO and will have the latest list of locomotive configurations and
their corresponding power and efficiency tables. If multiple LTO's
have the latest revision level, then the master LTO could be
selected from those LTO's by the highest serial number or some
other secondary selection method.
[0011] Versions of these LTO systems have been developed and
demonstrated since 2005 and appear to have been tested by several
class 1 railroads but never implemented in quantity. When utilized
only with diesel-fueled locomotives it was unlikely to save more
than 2% in fuel consumption under typical mainline freight
operations. In order for this system to be effective it would have
had to be installed in most locomotives of a particular railroads
fleet, and it didn't appear to offer a quick enough ROI to be worth
this large of an effort for any of the major railroads.
[0012] Commercially available LTO systems have calculated
alternative throttle settings primarily based on fuel efficiency
only. The operating manual for the LTO system offered by Invensys
describes an optional input signal channel for locomotive fuel
quantity but it is not evident that fuel quantity was used in any
calculations.
[0013] The most significant limitation of the current LTO systems,
is that they currently do not accommodate alternative fuels. As the
locomotive industry starts to implement a conversion to natural gas
as a substitute for diesel fuel, it is likely that it will take
more than 15 years for the industry to fully transition to
locomotives fueled only with natural gas. The first few years of
this transition is likely to be a transition to dual fuel
locomotives that can operate on 100% diesel fuel or a mixture of
natural gas and diesel. For the next 5 to 10 years train consists
will be mixed between locomotives operated on 100% diesel and
locomotives that could operate on either 100% diesel or a mixture
of diesel and natural gas. The locomotive fleet will not only have
locomotives that have different fuel efficiencies and fuel types,
but it will have individual locomotives that can operate on one
fuel or both fuels and change between these operating modes while
in operation.
[0014] When multiple fuels are used throughout a locomotive
consist, what is important is not consuming the least amount of
fuel, but consuming the least amount of the most expensive fuel. If
natural gas fuel is 40% cheaper than diesel fuel for an equivalent
amount of energy, it makes sense to focus the power from engines
using the natural gas even if that locomotive is 10% less thermally
efficient than the locomotive fueled by 100% diesel fuel.
[0015] What is desirable is an updated LTO system that can
accommodate not just a locomotive that consumes an alternative fuel
type but also a dual fuel locomotive that can change what type of
fuel it is consuming while in operation. Further this system should
require minimal operator input to configure and operate the train.
Additions of both new locomotive types and new fuel consumption
strategies should only require updating the locomotives equipped
with these new improvements and not require updating all LTO units
in a locomotive fleet.
BRIEF SUMMARY OF THE INVENTION
[0016] The present disclosure provides an independent throttle
optimization system in locomotive consists. Various examples of the
systems are provided herein.
[0017] The system is directed at improving the art of LTO systems
to accommodate both alternative fuels and dual fuel locomotives
while minimizing the amount of operator input and required LTO unit
database updates. Doing this requires incorporating the consumed
fuel type or multiple types as additional parameters in the
locomotive data that the LTO system stores and uses for
calculations. This further requires calculating the alternative
throttle settings with the goal of consuming the highest ratio of
low cost fuel over high cost fuel instead of only a focus on
consuming the least amount of one fuel. This may also require
ongoing communication between the LTO systems in a consist of what
fuel operating mode each dual fuel locomotive is in. Optionally,
incorporating the database revision version or date in each LTO
systems initialization string will allow selecting an LTO with the
latest database and programming as the master LTO system, thus
reducing the need to make fleet wide LTO database updates as new
locomotive configurations are added to the fleet.
[0018] One embodiment of this LTO as implemented is basically an
add-on control box installed into a locomotive with no changes to
the locomotive hardware. If the LTO is not functioning, the
locomotive will still operate normally. While the LTO does not make
any hardware changes, it does make a break into the throttle
control signal wires. It will intercept the throttle command signal
from the MU cable and either sends that throttle command or a
modified throttle command to that locomotives engine control
system. Each LTO box works in conjunction with other LTO boxes in
the same consist to calculate the optimum alternate throttle
settings among the different locomotives in the consist to give the
engineer the total power requested with his throttle command, but
in the most cost effective or fuel efficient manner possible with
some engines at higher throttle notch and some at lower throttle
notch.
[0019] While the old LTO calculations went by fuel consumption per
throttle notch, the new LTO database will have to have at least two
fuel tables for each dual fuel locomotive, and an input from the
engine control of which fuel type it is running on.
[0020] Dual Fuel LTO systems will require a new input signal for
dual fuel locomotives indicating what mode the engine is operating
in: either dual fuel or 100% diesel. Also it will need a new
communications signal among the LTO boxes in a consist so that the
master LTO box will know what fuel operating mode the dual fuel
locomotives are operating in.
[0021] Further the throttle setting optimization calculation will
now have two steps, first it will focus the fuel burn on the
locomotives that can replace the most diesel fuel with natural gas
and maximize the total natural gas consumption, then it will work
between the remaining locomotives to consume the least amount of
diesel fuel for the remainder of the needed power.
[0022] An optional upgrade to the LTO system would be an additional
channel or signal to communicate to certain locomotives in the
consist that they can be shut down. This may require an output
signal to an independent Automatic Engine Start Stop system. This
could be triggered after a time period at lower throttle settings
when there are multiple dual fuel locomotives and one diesel only
locomotive which would not be operated at any throttle setting
below notch 7. This feature would save a lot on locomotive
emissions and fuel consumption by eliminating the idling of
locomotives that will not be used for a long while.
[0023] If four GE-9 locomotives are in a consist and the throttle
command is notch 5 (50% load) the optimum fuel burn under a prior
art diesel fuel only LTO would have been to pick two units to leave
at notch 8, and idle the other two. If they were all dual fuel
units the calculation is more complicated. Conventional dual fuel
locomotives only replace 45% of the diesel with natural gas at high
throttle settings, but at notch 5 they replace 70% of the diesel.
In this case the calculation to consume the most natural gas would
result in all four units operating at notch 5 which would have
replaced the most diesel fuel with natural gas thus saving the
railroad more money and emitting less emissions. This is in spite
of the fact that the most efficient setting on an actual energy
basis would have still been to put a pair of locomotives at full
throttle and a pair at idle.
[0024] Instead of being an add-on box to the locomotive system, the
LTO can also be built into the control systems used for converting
the locomotive to dual fuel. Most current Energy Conversions Inc.
(ECI) conversion systems use a throttle notch relay to manipulate
the throttle signal in the same way a prior art U.S. Pat. No.
8,095,253 LTO box did. If there is a malfunction with the dual fuel
conversion, the throttle notch relay disconnects the ECI control
box from the engine controller and the MU cable throttle signal
passes through to the engine control as if the ECI control box is
not there. The new embodiment, combine Dual Fuel/LTO controller
could have this same throttle notch relay feature built in.
[0025] In order to add the LTO system into a dual fuel control
system, it may only require the additional programming and hardware
so that it communicates with the other LTO systems in the consist
across the MU cables.
[0026] With the LTO features incorporated into dual fuel conversion
systems and the large amount of money that can be saved by focusing
the fuel consumption in the natural gas locomotives, there will
likely be an add-on LTO added to every diesel powered locomotive
that will be operated in consists with dual fuel locomotives.
[0027] The present disclosure provides a locomotive consist system
comprising at least two locomotives, wherein each locomotive
includes a locomotive throttle optimizer (LTO), wherein at least
one locomotive includes an alternate fuel type. At least one LTO
device is a master LTO device in communication with every other LTO
device, wherein the master LTO device includes a controller and a
memory coupled to the controller, wherein the memory is configured
to store program instructions executable by the controller. The
master LTO may be the LTO with the most recent software update.
[0028] In response to executing the program instructions, the
controller is configured to receive an engineer throttle notch
value corresponding to a total power value, and access a database
including locomotive information for each locomotive in the
consist. The locomotive information includes a fuel type used in
the locomotive, a fuel consumption rate corresponding to each of a
plurality of throttle notch power levels, and a fuel consumption
priority parameter corresponding to each fuel type used in the
locomotive. The controller is also configured to generate an
alternate throttle setting for each locomotive, wherein the
alternate throttle setting includes a selected throttle notch power
level. The combination of alternate throttle settings for the at
least two locomotives produces a generated total power that is
equivalent to the received total power value, wherein the alternate
throttle setting is based on the fuel consumption priority
parameter. The controller is also configured to communicate the
alternate throttle setting to each locomotive.
[0029] In an example, the fuel consumption priority parameter
includes a fuel consumption cost for each throttle notch power
level, wherein the alternate throttle setting is based on
minimizing the total fuel cost. In another example, the fuel
consumption priority parameter includes a fuel cost, wherein the
controller is configured to calculate for each throttle notch power
level a fuel consumption cost, wherein the alternate throttle
setting is based on minimizing the total fuel cost
[0030] In another example, the master LTO device receives a signal
from each LTO device indicating an operating mode for the
locomotive, wherein the operating mode is selected from a primary
fuel mode or a dual fuel mode.
[0031] The master LTO device may receive a signal from each LTO
device indicating an amount of each fuel type available within the
locomotive, wherein at least one locomotive includes an alternate
fuel type, wherein the generated alternate throttle setting for
each locomotive is based on maximizing an alternative fuel type
consumption rate.
[0032] The fuel type may be diesel fuel, natural gas, and/or an
alternative fuel, or combinations thereof. For example, a fuel type
may be a combination of an alternative fuel type and a second fuel
type.
[0033] In an example, at least one locomotive is a dual fuel
locomotive including a first fuel type and a second fuel type. The
database includes a plurality of first fuel consumption rates of
the first fuel type and a plurality of second fuel consumption
rates of a second fuel type, wherein each first consumption rate
corresponds to a first fuel power value and a first fuel cost and
each second consumption rate correspond to a second fuel power
value and a second fuel cost, wherein a total fuel cost is the sum
of the first fuel cost and second fuel cost. In such example, the
controller generates an alternate throttle setting for the dual
fuel locomotive including a selected first fuel consumption rate of
the first fuel type and a selected second fuel consumption rate of
the second fuel type, wherein the alternate throttle setting for
the dual fuel locomotive is based on minimizing the total fuel
cost.
[0034] In an example, the first fuel cost and second fuel cost are
automatically and periodically updated to reflect the market price
of the first fuel and second fuel.
[0035] The master LTO device may receive a signal from each LTO
device indicating an amount of each fuel type available within the
locomotive, wherein at least one locomotive includes an alternate
fuel type, wherein the generated alternate throttle setting for
each locomotive is based on equalizing an alternative fuel type
consumption among the locomotives.
[0036] The system may include a single fuel locomotive including a
single fuel type and a single fuel LTO device in communication with
the single fuel locomotive, wherein the single fuel LTO device is
in communication with the controller. In such example, the database
includes a plurality of single fuel consumption rates for the
single fuel type, wherein each single fuel consumption rate
corresponds to a single power value and a single fuel cost. In
addition, the controller may generate an alternate throttle setting
including a selected first fuel consumption rate of the first fuel
type, a selected second fuel consumption rate of the second fuel
type, and a selected single fuel consumption rate of the single
fuel type. The received total power value may be equal to the sum
of the first fuel power value of the selected first fuel
consumption rate, the second fuel power value of the selected
second fuel consumption rate, and the single fuel power value of
the selected single fuel consumption rate. A total fuel cost is the
sum of the first fuel cost, second fuel cost, and the single fuel
cost. The alternate throttle setting is based on minimizing the
total fuel cost.
[0037] The disclosure also includes a method for producing
alternate throttle setting for at least two locomotives in a
consist, wherein each locomotive includes a locomotive throttle
optimizer (LTO). The method includes receiving an engineer throttle
notch value corresponding to a total power value. The method
further includes accessing a database including locomotive
information for each locomotive in the consist, wherein the
information includes a fuel type used in the locomotive, a fuel
consumption rate corresponding to each of a plurality of throttle
notch power levels, and a fuel consumption priority parameter
corresponding to each fuel type used in the locomotive. In
addition, the method includes generating an alternate throttle
setting for each locomotive, wherein the alternate throttle setting
includes a selected throttle notch power level. The combination of
alternate throttle settings produces a generated total power that
is equivalent to the received total power value, wherein the
alternate throttle setting is based on the fuel consumption
priority parameter. The method includes communicating the alternate
throttle setting to each locomotive.
[0038] The fuel consumption priority parameter may include a fuel
consumption cost for each throttle notch power level, wherein the
alternate throttle setting is based on minimizing the total fuel
cost. The fuel consumption priority parameter may include a fuel
cost, wherein the method includes calculating for each throttle
notch power level a fuel consumption cost, wherein the alternate
throttle setting is based on minimizing the total fuel cost.
[0039] The method may further include receiving a signal from each
LTO device indicating whether each LTO is operating in a primary
fuel mode or dual fuel mode. In addition, the method may include
receiving a signal from each LTO device indicating the amount of
each fuel type available within the locomotive, wherein the
generated alternate throttle setting for each locomotive is based
on preserving an alternative fuel type.
[0040] The fuel type may be diesel fuel, natural gas, an
alternative fuel, or combinations thereof. At least one locomotive
is a dual fuel locomotive including a first fuel type and a second
fuel type, wherein the database includes a plurality of first fuel
consumption rates of the first fuel type and a plurality of second
fuel consumption rates of a second fuel type. Each first
consumption rate corresponds to a first fuel power value and a
first fuel cost and each second consumption rate correspond to a
second fuel power value and a second fuel cost, wherein a total
fuel cost is the sum of the first fuel cost and second fuel cost.
The method includes generating an alternate throttle setting for
the dual fuel locomotive including a selected first fuel
consumption rate of the first fuel type and a selected second fuel
consumption rate of the second fuel type, wherein the alternate
throttle setting for the dual fuel locomotive is based on
minimizing the total fuel cost.
[0041] The method may include automatically and periodically
updating the first fuel cost and second fuel cost to reflect the
market price of the first fuel cost and second fuel cost.
[0042] The method may also include receiving a signal from each LTO
device indicating an amount of each fuel type available within the
locomotive, wherein at least one locomotive includes an alternate
fuel type, wherein the generated alternate throttle setting for
each locomotive is based on equalizing an alternative fuel type
consumption among the locomotives.
[0043] An advantage of the present subject matter is that it
accommodates alternative fuels in a consist by adding a "fuel type"
parameter in the locomotive configuration table for the throttle
notch, power and fuel consumption.
[0044] In addition, the present subject matter revises substitution
calculations by including a fuel type energy cost/value with the
fuel type in the LTO locomotive configuration database.
[0045] By assigning the master LTO by update revision or date, the
present subject matter always has the latest locomotive
configurations in the master LTO and the latest relative fuel
values. Accordingly, fleet wide LTO updates are never needed.
[0046] Yet another advantage of the present subject matter is that
it accommodates more than one fuel type at a time in the consist.
In addition, the present subject matter accommodates more than one
engine operating mode in a dual fuel locomotive.
[0047] Another advantage is that the present subject matter
interfaces with or incorporates an AESS for idle shut down.
[0048] Additional objects, advantages and novel features of the
examples will be set forth in part in the description which
follows, and in part will become apparent to those skilled in the
art upon examination of the following description and the
accompanying drawings or may be learned by production or operation
of the examples. The objects and advantages of the concepts may be
realized and attained by means of the methodologies,
instrumentalities and combinations particularly pointed out in the
appended claims.
BRIEF DESCRIPTION OF THE DRAWINGS
[0049] The drawing figures depict one or more implementations in
accord with the present concepts, by way of example only, not by
way of limitations. In the figures, like reference numerals refer
to the same or similar elements.
[0050] FIG. 1 is a is block diagram of a locomotive consist.
[0051] FIG. 2 is a table listing some locomotive parameters and
sample alternate throttle settings.
[0052] FIG. 3 is a table of different locomotive consists with
calculated benefits from using an LTO.
[0053] FIG. 4 is a schematic of an embodiment of the system
disclosed herein including a controller in communication with a
memory and a database.
DETAILED DESCRIPTION OF THE INVENTION
[0054] Alternate Fuel is defined as any fuel used in a locomotive
that is not diesel fuel, examples include natural gas, hydrogen,
ethanol, propane or Dimethyl Ether.
[0055] Dual Fuel locomotive is defined as a locomotive that can
operate at rated power on different fuels at different times.
Typically this is a locomotive that will operate on 100% diesel and
then when natural gas is available it will substitute as much
natural gas for diesel fuel as the engine will tolerate. In
well-developed conversions, the amount of diesel fuel could be
reduced to 5% or 10% that acts to pilot ignite the main natural gas
charge. A dual fuel locomotive may also use another alternative
fuel such as hydrogen or cellulosic ethanol as a primary fuel with
a small amount of diesel fuel as a pilot for ignition.
[0056] In the following detailed description, a plurality of
specific details, such as specific signals used for multiple
locomotive control in a consist and exemplary fuel burn rates and
efficiency calculations, are set forth in order to provide a
thorough understanding of the preferred embodiments discussed
below. The details discussed in connection with the preferred
embodiments should not be understood to limit the present
invention.
[0057] FIG. 1 is a block diagram of a locomotive consist 10. The
consist 10 includes a plurality of dual fuel locomotives 110, LNG
tender 115, and locomotives 100. Each locomotive 100 is provided
with a Locomotive Throttle Optimizer (LTO) device 200 and each dual
fuel locomotive 110 is provided with an LTO device 210. An MU
jumper 199 electrically connects the locomotives 100, dual fuel
locomotives 110 and LNG tender car 115 together in a MU consist. At
the present time, the standard MU jumper includes 27 conductors.
Preferred embodiments of the invention make use of conductors
included on standard MU jumpers 199 for communications between all
of the LTO devices 200 and LTO devices 210. Although the LNG Tender
does not have an LTO device installed it may have an MU jumper 199
at each end to pass the MU train line power and signals through it
to the rail vehicles adjacent to it on each end. In alternative
embodiments, additional conductors (which may be included in the MU
jumpers 199 or may be provided via physically separate cables) may
be added for such inter-locomotive communications, or wireless
communications may be used instead. It should further be recognized
that additional cars (e.g., freight cars) may also be present in
consists and that such non-locomotive vehicles may be interposed
between locomotives in the consist (such consists are sometimes
referred to as distributed power consists).
[0058] Although each locomotive 100 includes an LTO device 200 and
each dual fuel locomotive 110 includes an LTO device 210 in the
consist 10 of FIG. 1, it should be understood that it is possible
for some of the locomotives in the consist not to be equipped with
an LTO device in some embodiments. In such embodiments, the engine
control signals on those locomotives not equipped with an LTO
device may be electrically connected to the signals on the MU
jumper corresponding to the throttle position set on the lead
locomotive in the conventional manner. In other words, if a
locomotive in the consist 10 does not have an installed LTO device,
that locomotive will be controlled in accordance with the notch
selected by the operator in the lead locomotive.
[0059] Traditional LTO devices are equipped with locomotive
configuration data tables for each available locomotive
configuration that at a minimum incorporates the power produced and
the fuel consumed at each throttle notch. LTO device 210 is a new
embodiment of the LTO device concept for use with alternative fuel
and dual fuel locomotives. Because of this the locomotive
configuration tables also need to incorporate a fuel type parameter
and the relative energy cost of that fuel type. The LTO 210
locomotive configuration tables will need to accommodate the dual
fuel nature of the dual fuel locomotive with a table for each
possible operating mode. In one operating mode it may run on 100%
diesel fuel so it will only need the basic table with power and
fuel consumption for each notch. If there is an additional dual
fuel operating mode with multiple fuels, the LTO device 210 will
need to have additional tables. These additional multi fuel tables
will still have a single power value for each throttle notch, but
will also have to incorporate a fuel consumption value for each
fuel consumed at that throttle notch. It will also need parameters
to indicate the particular fuel types being consumed and their
energy costs compared to diesel fuel. There also should be a
parameter set for what operating mode the particular locomotive is
currently operating at and this parameter needs to be communicated
to the Master LTO if it changes. In some instances a dual fuel
locomotive 110 that was operating in dual fuel mode consuming a
mixture of natural gas and diesel fuel could no longer have an
available supply of natural gas fuel. In this instance the master
LTO device that is calculating the alternative throttle settings
should be aware that this particular dual fuel locomotive is no
longer consuming natural gas. This should initiate a new set of
calculations that may come up with different alternative throttle
settings to consume more natural gas on other locomotives in the
consist now that this dual fuel locomotive is consuming only diesel
fuel.
[0060] LTO device 200 could be considered a basic LTO device as
known in the prior art that would work on existing technology
diesel fueled locomotives. In order to work with LTO devices 210
these LTO devices 200 would have to have a compatible
communications protocol with the appropriate initialization
information that a newer LTO device will be able to communicate
with it, recognize it and issue it alternative throttle
commands.
[0061] It is projected that dual fuel locomotives are only a
transition technology as the railroad industry starts to use
different alternative fuels. More stringent emissions regulations
over time should make it impractical to have a locomotive consume
multiple fuels at both low emissions and high efficiency. The
current thought is that natural gas will replace diesel fuel for
the next several decades, but as technology evolves the future
alternative fuel could be some other gas or liquid fuel such as
hydrogen or cellulosic ethanol.
[0062] Future locomotives that may run on a single fuel again may
consume only natural gas or hydrogen. In this case the LTO device
200 will need one modification from the current prior art. It will
need an identifier of what its fuel type is in addition to its
minimal table of power and fuel consumption at each throttle notch.
When the dual fuel LTO device 210's are first implemented, it may
be the case that an LTO device 200 that does not have a fuel type
parameter in its initialization string will be assumed to operate
on 100% diesel fuel and only other types of fuel will need to be
identified.
[0063] As there are over 20,000 locomotives in service in North
America and most of them can operate in MU consists, the LTO
concept is initially devised as an add-on control box that is
incorporated into an existing locomotive. In other embodiments the
LTO device can be incorporated into another add-on control box that
is the basis for converting an existing diesel locomotive to
operate on dual fuel. Further the features of the LTO system can be
incorporated into the control systems of new locomotives.
[0064] FIG. 2 is a table of locomotive data. The first column
indicates the typical throttle notches that locomotives are
operated at with Notch 8 being full power that is incrementally
reduced down to Notch 1, minimum tractive power, followed by both
the Idle throttle notch and the Dynamic Brake throttle notch.
[0065] Column 2 is a representative duty cycle for a locomotive in
linehaul freight service. Noticeable is that the locomotive spends
most of its time in either idle or at Notch 8. Although the time
spent at idle is over twice the time spent at Notch 8, at idle the
locomotive consumes less than 2% of the Notch 8 fuel flow.
[0066] Column 3 is a sample breakdown of the engine power produced
by a 4000 hp locomotive in the various throttle notch settings.
[0067] Column 4 is a sample list of diesel fuel substitution rates
for an early dual fuel system on a 4 stroke GE locomotive. The
trend in these numbers is typical for dual fuel natural gas
conversion systems based on fumigating the intake on an unmodified
diesel engine. The highest rate of substitution is at a lower
throttle setting somewhere between 1/4 and 1/2 load. As the power
setting approaches full load the engine becomes sensitive to engine
knocking and the substitution rate has to be reduced. Also as the
engine operates at very low loads approaching idle, it operates so
lean that it has trouble maintaining high enough cylinder
temperatures to burn any natural gas that is injected. In this
case, from Notch 2 down thru Dynamic Braking the engine runs on
100% diesel fuel. It is by avoiding 100% diesel operating in
throttle notches 1 and 2 that the LTO systems offer the most value
as it calculates and applies alternate throttle settings.
[0068] Column 5 is a sample list of diesel fuel substitution rates
for a converted dual fuel EMD engine in a locomotive application.
Unlike a fumigation based dual fuel system typically installed on a
four stroke engine, this engine was significantly modified during
the dual fuel conversion to have a very high substitution rate at
full load. With improved aftercooling and a lowered compression
ratio this engine can operate with up to 92% of the diesel fuel
being displaced by natural gas. In this case the trend is that the
gas substitution is highest at full load and drops steadily as
engine load is reduced. This is because the two stroke engines on
average operate leaner than four strokes and as the load is reduced
the air to fuel ratio increases even further in these unthrottled
engines. As seen in the four stroke engine, as the engine
approaches Notch 2, the air fuel ratio is so high and combustion
temperatures so low that the natural gas will not burn. As in the
case of current locomotive four stroke fumigation system, the
current dual fuel EMD engine system will operate from Notch 2 down
thru dynamic brake on 100% diesel.
[0069] The additional columns in this chart illustrate the
application of alternate throttle notches to a consist containing
two dual fuel locomotives and one conventional diesel locomotive.
Column 6 illustrates the power request from the train operating
engineer. This is simply a function of multiplying the single
locomotive power level at that throttle notch setting by the number
of active locomotives in the consist. Column 7 is a sample list of
applied power settings when the alternate throttle settings are
applied. It illustrates that there will be a range of deviation
that is allowed between what is requested by the engineer and what
is applied. This deviation is likely to be 5% or less, and should
be configurable in the design and setup of the LTO system. Because
the throttle notch settings are discrete setting, it is unlikely to
get an exact match of alternate throttle setting power and
requested power.
[0070] Column 8 contains a sample of likely applied alternate
throttle settings for the consist if the dual fuel locomotives were
EMD locomotive. Because the natural gas substitution rate is
highest at notch 8, it is apparent that the systems maintains at
least one of the dual fuel locomotives in notch 8 whenever possible
and commands the conventional diesel locomotive to operate at the
lowest throttle setting possible, including idle.
[0071] Column 9 contains a sample of likely applied alternate
throttle settings for the consist if the dual fuel locomotives are
GE 4 strokes with fumigation dual fuel systems. Because the peak
substitution rate happens at a lower throttle setting, the
alternate throttle results are not the same as the EMD based
system. It may be non intuitive, but the goal will be to keep as
many of the dual fuel GE locomotives in Notch 7 as possible as that
is where the highest amount of natural gas is consumed. It is not
where the peak replacement rate is, but as the amount of natural
gas consumed is a function of both the power produced and the rate
of diesel substitution, in this example, Notch 7 is where the most
natural gas is consumed. It is the purpose of these new LTO systems
not to reduce the total amount of energy consumed, but to consume
the highest proportion of the lowest cost fuel. This typically has
the beneficial side effect of generating the lowest amount of
criteria emissions and greenhouse gasses also. The trend in this
column is to keep at least one dual fuel locomotive in notch 7 as
long as possible, and then generate the most power possible with
the pair of dual fuel locomotives.
[0072] In both the EMD and GE alternate throttle setting columns,
the highest power setting was applied to the first of the dual fuel
locomotives, this is only for example. It is likely the LTO system
would alternate which dual fuel locomotive was at a higher power
setting in order to either balance the wear and tear on the engine
or the natural gas fuel consumption depending on the fuel storage
type and quantity. Some future natural gas locomotives may use
onboard natural gas storage and their fuel quantity will need to be
considered as alternate throttle settings are calculated as a
dedicated natural gas locomotive that runs out of fuel will not be
able to apply power in a consist when the engineer has requested
full power from all of the locomotives in the consist.
[0073] Although notch 8 is the throttle setting used predominantly
while in operation pulling freight, almost twice as much time is
spent in Notches 1 thru 6 where the diesel only locomotive is
idling. An alternate embodiment of the LTO system could incorporate
a signal that will initiate an idle shutdown of the locomotive
least likely to be turned on until the engineer moves the throttle
up past notch 6. If this consist had more than 1 conventional
diesel locomotive in a consist with a pair of dual fuel units, this
opportunity to shut down at least one diesel locomotive would occur
for longer periods and more often. Although the fuel cost savings
would not be that significant do to the low fuel consumption at
idle, the emissions reductions would be substantial. Because of the
colder combustion temperatures at idle, the hydrocarbon, CO and PM
emissions of the locomotives are worst at idle. For this reason
most locomotives have been equipped with automatic engine start
stop (AESS) systems and during the implementation of an LTO system,
this AESS system could be incorporated into the LTO system or the
LTO system could incorporate an output that would signal to an
external AESS system that it can stop idling as long as it is safe
for the engine to do so. The AESS systems are designed to start up
occasionally to keep the engines coolant warm, in this application
they would allow the shut down engine to be brought back into
service quickly if the engineer requested a power setting requiring
the power from the shut down locomotive.
[0074] FIG. 3 is a table indicating some different consist
configurations and the benefits of a possible LTO system in these
configurations. The first column is the configuration of the
consist listing the locomotives being used. `GE` represents a
conventional diesel powered locomotive whereas `DF.GE` represents a
typical dual fuel converted GE locomotive. `EMD` represents a
typical diesel powered EMD locomotive whereas `DF.EMD` represents a
typical dual fuel converted EMD locomotive. These consists are for
example only as any combination of conventional and dual fuel
locomotives could be combined with locomotives from either
manufacturer.
[0075] The second column illustrates the diesel substitution rate
for the consist without the use of an LTO system and the third
column is an example of the diesel fuel substitution rate with a
sample LTO system in operation. The fourth column is a calculation
of how much the substitution rate was improved by the application
of the LTO system and the last column is a calculation of how much
in fuel cost is saved per year per locomotive with the addition of
an LTO system to each locomotive.
[0076] Some interesting points from the table, without an LTO
system, row 1 indicates that the basic substitution rate for a
sample GE dual fuel locomotive is 41.29%, this means that 41.29% of
the diesel fuel that would have been consumed has been replaced by
natural gas on an energy content basis. When an LTO system is used,
the substitution rate increases to 42.42%, which is almost a 3%
improvement and nets a yearly fuel savings of $7,955 per locomotive
which should be more than the cost of an LTO add on system. Below
the table are the fuel cost and consumption values used to
calculate these fuel savings numbers.
[0077] Row 2 is the same pair of dual fuel locomotives in a consist
with an added single diesel powered locomotive. With the consist
not using an LTO system the substitution rate of 41.29% for the
pair drops to 23.95% for all three locomotives. When an LTO system
is added the substitution rate jumps almost 20% to 28.64% and the
yearly fuel savings jumps to $33,018 per locomotive which is over 6
times the predicted cost for the LTO device. The next row with a
second diesel locomotive added to the consist continues the trend
of improvement with a 30% increase in substitution rate and $37,664
in yearly fuel savings per locomotive.
[0078] Row 4 and down is a similar progression of consists but
using EMD 2 stroke locomotives with a higher diesel fuel
substitution rate. In Row 4 the EMD overall substitution rate is
78.30% showing the added value of the more extensive conversion
process over the GE 4 stroke fumigated dual fuel locomotives at
41.29%. When the LTO system is added to a pair of dual fuel EMD
locomotives, the substitution increase is also greater at a 4%
increase in substitution, and because we were already substituting
more diesel the increase is compounded in effectiveness and this
system now saves almost 3 times as much in yearly fuel costs at
$21,824 per locomotive.
[0079] In row 5, when two dual fuel EMD's are operated with a
single diesel fueled locomotive the substitution rate again
increases around 20% and yields a yearly fuel cost savings per
locomotive of $74,624. The same trend as before is noticed when a
fourth diesel fueled locomotive is added in row 6.
[0080] As mentioned above and shown in FIG. 4, aspects of the
systems and methods described herein are controlled by one or more
controllers 12. The one or more controllers 12 may be adapted to
run a variety of application programs, access and store data,
including accessing and storing data in the associated databases
16, and enable one or more interactions as described herein.
Typically, the controller 12 is implemented by one or more
programmable data processing devices. The hardware elements,
operating systems, and programming languages of such devices are
conventional in nature, and it is presumed that those skilled in
the art are adequately familiar therewith.
[0081] For example, the one or more controllers 12 may be a PC
based implementation of a central control processing system
utilizing a central processing unit (CPU), memory 14 and an
interconnect bus. The CPU may contain a single microprocessor, or
it may contain a plurality of microprocessors for configuring the
CPU as a multi-processor system. The memory 14 may include a main
memory, such as a dynamic random access memory (DRAM) and cache, as
well as a read only memory, such as a PROM, EPROM, FLASH-EPROM, or
the like. The system may also include any form of volatile or
non-volatile memory 14. In operation, the memory 14 stores at least
portions of instructions for execution by the CPU and data for
processing in accord with the executed instructions.
[0082] The one or more controllers 12 may also include one or more
input/output interfaces for communications with one or more
processing systems. Although not shown, one or more such interfaces
may enable communications via a network, e.g., to enable sending
and receiving instructions electronically. The communication links
may be wired or wireless.
[0083] The one or more controllers 12 may further include
appropriate input/output ports for interconnection with one or more
output mechanisms (e.g., monitors, printers, touchscreens,
motion-sensing input devices, etc.) and one or more input
mechanisms (e.g., keyboards, mice, voice, touchscreens, bioelectric
devices, magnetic readers, RFID readers, barcode readers,
motion-sensing input devices, etc.) serving as one or more user
interfaces 30 for the controller 12. For example, the one or more
controllers 12 may include a graphics subsystem to drive the output
mechanism. The links of the peripherals to the system may be wired
connections or use wireless communications.
[0084] Although summarized above as a PC-type implementation, those
skilled in the art will recognize that the one or more controllers
12 also encompasses systems such as host computers, servers,
workstations, network terminals, and the like. Further one or more
controllers 12 may be embodied in a device, such as a mobile
electronic device, like a smartphone or tablet computer. In fact,
the use of the term controller 12 is intended to represent a broad
category of components that are well known in the art.
[0085] Hence aspects of the systems and methods provided herein
encompass hardware and software for controlling the relevant
functions. Software may take the form of code or executable
instructions for causing a controller 12 or other programmable
equipment to perform the relevant steps, where the code or
instructions are carried by or otherwise embodied in a medium
readable by the controller 12 or other machine. Instructions or
code for implementing such operations may be in the form of
computer instruction in any form (e.g., source code, object code,
interpreted code, etc.) stored in or carried by any tangible
readable medium.
[0086] As used herein, terms such as computer or machine "readable
medium" refer to any medium that participates in providing
instructions to a processor for execution. Such a medium may take
many forms. Non-volatile storage media include, for example,
optical or magnetic disks, such as any of the storage devices in
any computer(s) shown in the drawings. Volatile storage media
include dynamic memory, such as the memory 14 of such a computer
platform. Common forms of computer-readable media therefore include
for example: a floppy disk, a flexible disk, hard disk, magnetic
tape, any other magnetic medium, a CD-ROM, DVD, any other optical
medium, punch cards paper tape, any other physical medium with
patterns of holes, a RAM, a PROM and EPROM, a FLASH-EPROM, any
other memory chip or cartridge, or any other medium from which a
controller 12 can read programming code and/or data. Many of these
forms of computer readable media may be involved in carrying one or
more sequences of one or more instructions to a processor for
execution.
[0087] It should be noted that various changes and modifications to
the embodiments described herein will be apparent to those skilled
in the art. Such changes and modifications may be made without
departing from the spirit and scope of the present invention and
without diminishing its attendant advantages. For example, various
embodiments of the method and portable electronic device may be
provided based on various combinations of the features and
functions from the subject matter provided herein.
* * * * *