ELECTRIC DRIVE VEHICLE, SYSTE AND METHOD
FIELD
[00 The subject matter disclosed here relates to electric drive systems, and methods of
operating such a electric drive system.
BACKGROUND
[0002] Vehicles including internal combustion engines ma be operated in environments,
such as mining shafts, which have stringent emissions and ventilation regulations. In such
environments, the use of internal combustion engines may be prohibited, and/or the number of
engines that may be operated at a given moment may be limited. As such, this also limits the
number of vehicles that may be operated a a give moment In that environment.
BRIEF DESCRIPTION OF THE INVENTION
[00031 Methods and systems are provided for operating an electric drive for vehicle, such
as a mining apparatus. n one embodiment, the electric drive comprises a motor capable of
propelling the vehicle, and an energy storage device coupled to the motor. The energy storage
device may be selectively couplable to a catenary line, wherein the catenary line is capable of
supplying electrical power to the vehicle and to the energy storage device. The electric drive
system of the vehicle may then be control led based on the operating mode of the vehicle. In one
embodiment, the vehicle includes a mining device tha is operable to be powered by energy fro
one or more of the catenary line and the energy storage device. this configuration, during
some modes, the motor may be powered by the energy storage device thereby propelling the
vehicle., while during other modes, the external power source may power the motor while also
recharging the energy storage device. Further still, in some embodiments, power from the
energy storage device and the external power source may be combined. In this way, by
providing power to the electric drive from an board energy storage device, the need to operate a
combustion engine reduced.
| 0 4| one example, the vehicle is a mining vehicle including a mining ore cart. The
mini g vehicle is operated in a mining environment, such as a mining shaft, wherein emissions
and ventilations are stringently regulated. The mining vehicle is configured with a hybrid
electric drive including an engine, a traction motor for propelling the wheels of the vehicle a
hermetically sealed energy storage device including one or more battery modules, and a motor
for operating an associated mining device, such as a drill. Based on vehicle operating conditions,
a vehicle controller is configured to propel the mining vehicle and/or power the mining device
with energy from one or more of the energy storage device, the vehicle engine, and an external
power source. For example, when the mining vehicle and/or device are to be operated using
energy from the external power source, such as when an external power source is available,
and/or when the mining vehicle i traversing a section of higher (steeper) gradient, the controller
may selectively couple the vehicle to the external power source through a catenary line. Herein,
energy from the external power source is used to propel the vehicle and/or operate the drill,
while the energy storage device is charged concurrently As another example, when the mining
vehicle and/or device are to be operated us g energy from the energy storage device, such as
when an external power source i not available, whe the mining vehicle is in a no-engine
operation zone, and/or when the mining vehicle is traversing a section of lower (shallower)
gradient, the controller may selectively decouple the vehicle from the external power source's
catenary line. Herein, energy from the energy storage device is used to propel the vehicle and/or
operate the drill, until the externa! power source is avail !e again. Further still, when a boost is
required to propel the vehicle and/or operate the drill, energy from both the external power
source an the energy storage device can be combined to provide a larger amount of energy n
this way, the eed for operating the vehicle's engine is substantially reduced.
| 0 5| should be understood that the brief description above is provided to introduce in
simplified form a selection of concepts that are further described in the detailed description t is
not meant to identify key or essentia! features of the claimed subject matter, the scope of which
is defined uniquely by the claims that follow the detailed description. Furt hermore the claimed
subject matter is not limited to implementations that solve any disadvantages noted above or in
any part of this disclosure.
BRIEF DESCRIPTION OF THE DRAW INGS
0006 Reference is now made briefly to the accompanying drawings, in which:
[ 7| FIGS. 1-3 sho schematic depictions of example embodiments of a vehicle electric
dri e system;
[0008] FIG. 4 shows a perspective view of the electric drive system in a mining vehicle;
[0009} FIG. 5 shows a schematic depiction of the electric drive system n a mining
environment;
[001 Of FIGS. 6-7 show high level flow charts of methods for operating the electric drive
system of FIGS. 1-3;
[001 f FIG. 8A-D describe performance requirements, vehicle parameters, and motoring
parameters of an example vehicle including an electric drive system according to the present
disclosure;
[00 ) FIG. 9 shows a table listing all the possible operational modes for a mining vehicle
according to t present disclosure.
|00 ) Like reference characters designate identical or corresponding components and units
throughout the several views, which are ot to scale unless otherwise indicated.
DETAILED DESCRIPTION
[0014) A electric drive system (as shown in FIGS. 1-3) in a vehicle (as shown in FIG. 4)
may be operated in environments with stringent emissions and ventilation requirements (such as
shown in F G. 5 Based on the operating mode of the veliicle (FIG. 9) the electric drive system
may be coupled or decoupled from an external power source via a catenary line. When coupled,
the electric drive system can be operated using power from the external power source while also
charging a system bat ery When decoupled, the electric drive system can be operated using
power from the charged system battery. Further still based on the power requirement, power
from both the external power source and the energy storage device can be combined to provide
boosted power for vehicle propulsion and/or accessory operation. n such cases, the use of an
internal combustion engine to operate the vehicle's electric drive system is reduced. By reducing
the use of the interna! combustion engine, the usability of the vehicle i ventilation-limited
environments i improved.
[0015) FIG. 1 shows a first embodiment of an electric drive system 00 for a vehicle. As
non-limiting example, the vehicle is shown as a mining vehicle including a drill configured for
electric propulsion. The electric drive system 100 includes one or more electric motors 104. The
motors 104 include a traction motor capable of propelling the vehicle as well a a motor (e.g.,
drill motor) for operating mining device associated with the mining vehicle, herein drill 06.
n the depicted example, the mining device is used to drill into the face of mine wall. The
electric drive system 00 further includes an energy storage device . , herein depicted as a
battery system, coupled to electric motor 04. As elaborated with reference to F GS. 2-3, the
mining vehicle may be a hybrid electric system wherein electric drive system 100 is a hybrid
electric drive system coupled to an internal combustion engine of the vehicle n alternate
embodiments, where electric drive system is not coupled to a vehicle engine, the mining vehicle
may be an electric vehicle only.
0 .16 Energy storage device 108 includes a plurality of storage banks. Each storage bank
may include super-capacitors, ultra-capacitors, flywheels, batteries, or a combination thereof
'fhe batteries of energy storage device 8 can include one or more of lead-acid batteries, nickel
cadmium batteries, lithium ion batteries, nickel metal hydride batteries, and sodium metal halide
batteries, or battery systems n some examples, energy storage device 108 may include one or
more battery modules, each battery module including one more batteries of a given kind. The
different storage banks may be used separately or in combination. When used in combination,
the different storage banks can provide synergistic benefits no realized with the use of any one
single energy storage bank. For example, a flywheel system and an ultra-capacitor system can
be used to store and provide eSectrical energy relatively fast but each of these systems may be
relatively limited in its total energy storage capacity and duration. n comparison, a battery
system can be used to store energy relatively slowly bu has a . larger total energy storage
capacity. Thus, when the various energy storage banks are used in combination, the overall
storage and capture capabilities of the energy storage device are extended beyond the limits of
the ultra-capacitor system, the flywheel system or the battery system alone.
|00I7| Additionally, in some embodiments, energy storage device 108 s hermetically
sealed. Herein, by hermetic, it is meant t include not just a state of being air tight, but also
generally impervious to outside interference or influence. Thus, the energy storage device 08
generates substantially no heat or thermai exhaust, and emits substantially no fumes, gases or
vapors. Similarly, substantially no heat, thermal exhaust, gases, fumes, or vapors from the
ambient environment are able to infiltrate through the hermetic seal into the energy storage
device. Accordingly, in one embodiment, energy storage device 108 is hermetically sealed to
prevent contact of a flammable gas w h an interior volume of the energy storage device. In
another embodiment, in addition t being hermetically sealed, the energy storage device may be
thermally insulated so that no external surface of the energy storage device has a temperature
that i significantly higher than the ambient air. Herein, the energy storage device 108 can he
used in the flammable environment, and despite temperatures inside the energy storage device
being hig (e.g., 30()°C), the flammable gases in the ambient environment do not contact any
part of the energy storage device that has a temperature that is significantly higher than the
ambient temperature. This allows energy' storage device 8 to power motor 4 and/or operate
drill 106 while n contact with a flammable gas without igniting the gas. By using hermetically
sealed batteries, the vehicle can be advantageously used in various environments, including
environments with stringent emissions and ventilation requirements (such as, in mining shafts).
The emissions that are regulated may include, for example, NOx species, particulate matters,
CO-2, etc. Ventilation requirements may be needed for air quality, temperature management,
control of the concentration (e.g.. ppm) of combustible or inflammable gases (e g.. methane), or
a combination thereof. Additionally, the depicted configuration reduces thermal runaway,
arcing, and or other hazardous conditions.
|00I8| In still other embodiments, energy storage device may be coupled o a dedicated
cooling system (not shown) which provides forced cooling fluid to keep the batteries of energy
storage device 8 in a determined temperature ra ge. The cooling fluid may include one or
more of air, water, oil, or another suitable coolant. In another example, thermoelectric cooling
(e.g., peltier effect) may be used to cool the hermetically sealed batteries. Alternatively, a
cooling system associated with motor 104 (such as, a cooling system associated with a vehicle
wheel traction motor) may also interface with energy storage device 108 so that a common
cooling system is used to regulate the temperature of both the motor and the batteries.
f I | Energy storage device 108 may be further coupled to a battery management system
22. Battery management system 22 may include a non-transitory computer readable storage
medium earning code with instructions for propelling the vehicle, and/or powering one or more
devices associated with vehicle using energy from the energy storage device. The instructions
may include instructions for the various routines and methods described herein, such as in FIGS.
6-7. In this way, batter management system 22 may manage energy storage device. In one
example, as depicted, battery management system 22 i coupled to vehicle controller 12. in one
embodiment, as shown herein, a single battery management system may be configured to
manage and control all the energy storage banks (e.g., all the battery banks or battery modules)
of the energy storage device 108. n an alternate embodiment as elaborated with reference to
FIG. 4, each energy storage bank (e.g., each battery bank or battery module) of energy storage
device S is coupled to a dedicated battery management system.
[00201 The electric drive system may further include a control system, or controller 1.2. h
one embodiment, controller 12 may be a non-transitory computer readable storage medium
carrying code with instructions for adjusting operation of the vehicle and o e or more vehicle
components based on operating conditions. As shown n F GS. - , based on vehicle operating
conditions (such as, track grade, power availability, drilling requirements, tramming
requirements, etc.), and further based on operator input, the controlier may be configured to
determine the vehicle s operating mode (for example, as selected b a vehicle operator, or as
automatically selected by the controller based on the vehicle operating conditions) Based on the
vehicle's operating mode, the controller may be configured to selectively couple or decouple the
energy storage device to/from the external power source, and accordingly adjust a charging
operation of the batteries, drill operation, and/or vehicle propulsion.
[00211 Based on vehicle operating conditions, the energy storage device 8 is selectively
operable in one or ore operational modes. Specifically, based on the operating conditions, the
mining vehicle can be selectively coupled to, or decoupled from an external power source 102,
for example, via a catenary line 103. Accordingly, the energy storage device 108 may power
motor 104 (e.g., traction motor) to propel the vehicle while the motor i decoupled from catenary
line 103, or operate the mining device (e.g., dr l 106) while the mining device is decoupled from
catenary line 103. Alternatively, energy storage device 8 can boost motor 04 while the motor
is coupled to catenary line 3, or boost the mining device while the mining device is coupled to
catenary line 103. in this way, dril l 106 i operable using energy fro one or more of the motor
(for example, when the motor is operated using energy from the external power source), and the
energy storage device (for example, when no external power is available). A such, when
coupled, such as during a moving operation, catenary line 103 is also capable of supplying
electrical power to the energy storage device fo charging the energy storage banks, e.g., a
batters' system, for use during a subsequent tramming operation.
| 22 One or more of the energy storage device and the external power source can also be
used to power vehicle auxiliary loads, such as for example, one or more hydraulic pumps
configured to provide vehicle steering and/or braking assist, a vehicle HVAC system configured
to provide cabin heating and/ r air conditioning, and the like. While the depicted example
illustrates coupling of the energy storage device to the external power source vi the catenary
Sine, this is not meant in a limiting sense n alternate embodiments, the external power source
may an alternate electrical power source, such as a -phase 480V outlet.
[00231 Further still, in embodiments where electric drive system 100 includes a vehicie
engine (as show in F GS. 2-3), vehicle controller may operate one or more motors (e.g., traction
motors to propel the vehicle and/or drill motors to operate the drill) using energy from the engine
while the energy storage device is coupled to and charged by the catenary line. Still other
combinations of motor operation using one or more of a vehicle engine, energy storage device,
and external power source are possible, as discussed below with reference to FIG. 9 .
0024J F GS. 2-3 depict example detailed embodiments 200 and 300, respectively of the
hybrid electric drive system of FIG. for use in a hybrid mining vehicle (such as an ore cart)
operable in a mining environment. n the embodiments of FIGS. 2-3, one or more of energy
storage device 8 and vehicle engine 230 are configured to provide power to one or more
motors via one or more inverters so as to propel the vehicle and/or operate an associated device,
such as a drill.
[0025j Turning now to FIG. 2, embodiment 200 shows energy storage device 108 coupled
to a traction motor 206 via a first inverter 204 and to a drill motor 209 powering mining device
(e.g., drill) 106 though a second different inverter 208. As previously elaborated with reference
to FIG. 1, one or more energy storage banks of energy storage device 108 may be managed by
battery management system 22. As such, the combination of energy storage device 108, traction
motor 206, and first inverter 204 may define an electric power pack 202. Traction motor 206 can
power wheels 214 e her directly through drive train 220, or through transmission 210. the
depicted example, motor shaft 207 of traction motor 206 is coupled to hydrodynamic
transmission 2 . A suitable traction motor may be an AC motor (as depicted) or a DC motor.
In the event that the motor is a AC motor (as depicted herein), use of an inverter paired with the
traction motor allows the DC input from the energy storage device to be converted into an
appropriate AC input, such as a three-phase AC input, for subsequent use by the motor. In the
event that the motor is a DC motor, the motor can directly employ the output of the energy
storage device and transmission 2 along DC bus 222. Details relating to settings desired in the
motor are shown in the table of FIG. D
[0026] Vehicle engine 230 may be operated to propel the vehicle, charge energy storage
device 108, and/or power drill motor 209 of drill 106. n the depicted embodiment, vehicle
engine 230 is diesel e mine . However, in alternate embodiments, alternate enaine
configurations may be employed, such as a gasoline engine or a bio diesel or natural gas engine,
for example. Engine 230 generates a torque that is transmitted to an alternator 232 along drive
shaft (not shown). The generated torque is used by alternator 232 to generate electricity for
subsequent propagation of the mining vehicle. Engine 230 may be run at a constant speed,
thereby generating a constant horsepower (hp) output or at a variable speed and variable horse
power, depending o operational demand. The electrical power generated n this manner is
transmitted along an electrical bus to a variety of downstream electrical components. Based o
the nature of the generated electrical output, the electrical bus may be a direct current (DC) bus
or an alternating current (AC) bus. n the depicted example, electrical power generated by
engine 230 and transmitted through alternator 232 is rectified through one or more rectifiers
234, or inverters 204, 2 8 before being transmitted along a DC bus to energy storage device 108,
traction motor 206, and drill motor 209.
|0027| Torque generated by engine 230 i also transmitted to drive train 220 through
transmission 210. Drive trai 220 includes a selected arrangement of power distribution and
gear multiplication devices such as transmissions, gea sets, drive axles, differentials, torque
converters, and the like. Suitable power distribution topologies include a single traction motor
for all the wheels, or a single motor per axle-wheel. n the depicted embodiment, transmission
2 0 includes one or more gears, for example, to enable the transmission to operate at a fixed gear
reduction. Power (or torque) is then transmitted from transmission 210 to operate drive axle 212
and wheels 2 4, thereby propelling the mining vehicle DC power from energy storage device
08 and/or engine 230 can also be used to operate a mining device, such as drill 106. For
example, energy storage device 108 can be coupled to a drill motor 209 via a second inverter 208
to provide power to operate drill 106. Additionally, or optionally, engine 230 can be operated to
generate power that is used to operate drill motor 209.
[0028} FIG. 3 shows another embodiment of an electric drive system 300 for a vehicle in a
mining environment. Herein, i comparison to the embodiment of F G. 2, drill 106 and drill
motor 209 are coupled to motor shaft 20 downstream of hydrodynamic transmission 0 such
that no additional inverter is required when drill 106 is powered using the DC power source of
energy storage device 108 or engine 230
[0029 n the embodiments of FIGS. 2-3, energy storage device 108 and/or engine 230 may
also be used to power one or more additional loads with auxiliary functions. These auxiliary
loads ay include, for example, lighting, control systems, a r conditioning systems, veiitiiaiion
systems, and communications systems. The various auxiliary loads may be powered directly
from the energy storage device and/or engine, or through appropriate converters, such as
inverters, choppers, rectifiers, etc., as depicted. n one example, a mechanical load, such as drill
106, can be powered by a distinct inverter driven drill motor or may be driven off the shaft of
one or several motors used for vehicle propulsion. Other mechanical loads may include, for
example, hydraulic pumps and blowers. n one example, as depicted, motor shaft 207 can be
coupled to a hydraulic pump 2 6 to operate auxiliary loads 2 involved in providing steering
and/or braking assistance. Alternatively, dedicated electrical motors can be operated to drive the
pumps for such auxiliary functions. Example performance requirements, vehicle parameters, and
motoring parameters of a mining vehicle including the electric drive system of FIGS. 1-3, is
shown in the tables of F GS. 8A-C.
[00301 While FIGS. 2-3 include inverters, additional power electronics, such as DC/DC
converters and/or bi-directional boost converters, and additional electrical coupling devices, such
as contactors and diodes, may also be included in one exampie, a bi-directional boost converter
may be included in battery management system 22 to decouple the voltage of one energy storage
ba k, such as an ultra-capacitor or a first, larger battery bank, from the vo age of another energy
storage bank, such as a second, smaller battery bank. Other power electronics can also be
included in the battery management system 22, such as insulated gate bipolar transistors (IGBTs)
or thyri tor operating as pulse width modulators, for example.
003 The various power electronics may receive data pertaining to a battery's operating
condition including, but not iimited to, a batteiy state of charge (SOC), a batteiy temperature and
temperature gradient, a frequency of usage, a number of charging/discharging cycles that have
elapsed, a power transfer current and voltage, a total number of ampere hours in a
charge/discharge mode, total operating hours in charge/discharge mode, number of vehicle
missions completed, vehicle distance travelled, elapsed time in operation, and the like.
[0032] While the depicted embodiments relate t a battery powered mining drill vehicle, it
will e appreciated that this is not meant in a limiting sense, and that other equipment with an
alternate associated device (in place of, or in addition to the drill) is within the scope of
contemplation. Such other equipment and associated devices include one or more of roof
bolters, scaling machines, powder loaders, shuttle cars, front end loaders, haulers, scoops,
dumps, choppers, bolters, maintenance vehicles, shield haulers, and conveyors.
[0033] Further, while the depicted embodiments relate to a vehicle with a combustion
engine, it will be appreciated that this is not meant i a limiting sense, and that other vehicles
with an electric drive system that does not have (or has limited) on~board energy storage
capabilities, such as tethered vehicles that are connected to an external power source with a cable
application, are within the scope of contemplation. A such, in the case of tethered vehicles, the
number of vehicles operable n a given area may be further constrained by practical
considerations, such as the length of the cable, the risk of running over and cutting/damaging
cables, abrasion against rocks, etc.
[0034] Now turning to FIG. 4, i depicts a perspective view 400 of a mining vehicle
including an electric drive, such as the electric drive of FIGS 1-3. Specifically, perspective view
400 illustrates a packaging configuration of energy storage device 08 and motor 404 (e.g.,
traction motor 206 o drill motor 209) with respect to wheels 402 of min g vehicle 4 Herein,
energy storage device 10 8 includes a plurality of battery modules (e.g., six sodium battery
modules) coupled to AC motor 404 The plurality of battery modules are packaged above AC
motor 404. n some embodiments, an additional number of spare battery modules (e.g., two
modules) can be included in a space below the battery bank and adjacent to motor 404 (not
shown). The plurality of battery modules are hermetically sealed to prevent the battery from
having contact with the vehicle's environment. Additionally, each energy storage bank (e.g.,
each battery bank or battery module) of energy storage device 108 is coupled to a dedicated
battery management system 22,
035| As elaborated with reference to GS 5-7, based on vehicle operating conditions the
vehicle's electric drive system may be selectively coupled to or decoupled from an external
power source via a catenary line. For example, when traversing a section of track with higher
gradient, the electri c drive may receive power fro the extemal power source. Then, when
traversing a . section of track with a lower gradient, the electric drive may be decoupled from the
external power source. When coupled via the catenary line, the external power source may be
used to propel the vehicle, operate one or more associated devices (such as one or more drills or
pumps), and/or charge the energy storage device. Then, when decoupled, power from the energy
storage device may be used to propel the vehicle and/or operate the associated loads. Further
still, if boosted energy is required, power from both the energy storage device and the external
power source may be used in combination to provide the boosted energy.
[00361 Now turning to FIG. 5, it shows an example e bodi en 500 of the electric drive
system of FIGS. 1-3 i a mining vehicle (or mining apparatus) in a mining environment. A
mining vehicle 502 (such as, an ore cart) may include a hermetically sealed energy storage
device, such as battery bank 508, a propulsion system including one or more motors 504, and a
mining device 506 (herein, drill) The one or more motors include a traction motor coupled to
the wheels 503 of vehicle 502 and a drill motor coupled to mining device 506. In the depicted
embodiment, motor 504 may be operated to propel mining vehicle 502 and/or operate drill 506.
However, in alternate embodiments, separate motors ay be used. Mining vehicle 502 may be
operated in a mining environment, such as a mining shaft. The mining environment may have
regions of differing gradient. For example, the mini g environment may have a first region 510
of a first lower gradient, a second region 512 of a second higher gradient (the second gradient
higher than the first gradient), and a third region 4 of a third lower gradient (the third gradient
ower than the second gradient). Thus, steeper second regi n 512 may be preceded and followed
by shallower regions 0, 514.
[0037J When operating the vehicle through first region 5 0 with the first lower gradient,
vehicle 502 is propelled using energy from the energy storage device, that is, battery bank 508.
Thus, during the flatter section, the vehicle is self-powered as it runs off its on-board battery.
When vehicle 502 reaches a steep section of track, such as when operating through second region
512 with the second higher gradient, the vehicle engages a wayside catenary line 526. The
engagement may be achieved via an engagement device 522. Upon engagement, power from an
external power source 524, such as an off-board power line, may be received via catenary line
526, and used to propel vehicle 502 along the steep sectio Herein, propelling the vehicle using
energy from the energy storage device includes operating a traction motor coupled to the wheels
using energy from the energy storage device, while propelling the vehicle using energy from the
external power source includes operating the traction motor coupled to the wheels using energy
from the external power source. When engaged to the catenary li e, the external power source
524 may additionally be used to recharge the energy storage device, in preparation for another
self-powered operation. Thus, by the time vehicle 502 has traversed the steep section and has
reached the third region 514 with the Sower gradient, batteiy bank 508 may be fully charged such
that the vehicle and/or the associated drill 506 may be operated using power from the recharged
battery ba k. As such, propelling the vehicle using energy from the energy storage device (when
operating through the first or third region) includes decoupling the vehicle from the catenary
line. By selectively coupling the vehicle to a catenary line to charge the battery bank and propel
he vehicle using the external power source, the vehicle is able to traverse the steep section of
track without depleting the batteiy bank. Further, sufficient energy is retained in the batterybank
to allow the vehicle to be self-powered after the steep section. Also, by recharging the
batteiy bank while propelling the vehicle along the steep section, if extra power is required to go
uphill and/or run the drill (or other pumps) along the steep section, a combined power boost may
be provided from the charged battery in addition to the energy from the externa! power source,
thereby improving vehicle operations.
[00381 While the example of FIG. 5 illustrates propelling the vehicle and/or operating the
drill using energy from the energy storage device and/or via the catenary, it will be appreciated
that in hybrid electiic vehicle embodiments such as shown in FIGS. 2-3), wherein the vehicle
includes an internal combustion engine, additional operational modes may be provided, as shown
in table 900 of FIG. 9 One or more of the various power sources may be selected to propel the
vehicle by operating the traction motor, or power a mining device by operating a drill motor. A
controller may select from these various operational modes when the external power source is
available based on, for example, emissions requi e nts, battery state of charge, engine status
(engine temperature, need for maintenance, etc.). As one example, with the vehicle coupled to
the catenary line, the vehicle engine ay be shut-down (or shifted to a stand-by mode) while one
or more of the traction motor and the drill motor is operated using energy from the catenary line.
Concurrently, the battery ay be charged, f required, using energy from the catenary line.
Alternatively, with the vehicle coupled to the catenary line, the vehicle engine may be operated
so that one or more of the traction motor a d the drill motor is operated by the vehicle while the
batten' is optionally charged with external power via the catenary ine. Further still, with the
vehicle coupled t the catenary line, the vehicle engine may be operated so that one or more of
the traction motor and drill motor may be operated using power from the catenary line, wh e the
battery s concurrenilv charged using power from the vehicle engine (represented as charging (E)
in F G. 9), if required. As such, the vehicle engine may be shut down when the vehicle is
operated in no-engine operation zones, or where emissions and ventilations are regulated.
[0039 Various operational modes are also possible when the catenary line is decoupled
from the vehicle. A controller may select from these various operational modes when the
external power source is not available, for example, during scheduled or unscheduled power
interruptions, or when the vehicle is traversing a region which has no access to a wayside
catenary line. As one example, with the vehicle decoupled from the catenary line, the vehicle
engine may be operated so that one or more of the traction motor and drill motor may be
operated using power from the engine, while the battery is concurrently charged using power
from the vehicle engine if required. As another example, with the vehicle decoupled from the
catenary line, the vehicle engine may be operaied so that one or more of the traction motor and
drill motor are operated using power from the battery, while the battery is concurrently charged
using power from the vehicle engine, if required. Further still, with the vehicle decoupled from
the catenary line, the vehicle engine may be shut down so tha one or more of the traction motor
and drill motor are operated using power from the battery.
| 04 | In all such cases, if power demand surges, combined power may be provided from
the catenary line, energy storage device and/or batter}' to supplement the power provided by any
given power source i this way, by using a hybrid electric drive system including an engine and
an energy storage device, and with access to an external power source, various operational
modes are available to a vehicle operated in an environment with stringent ventilations and
emi ions regulation s .
(004 Now turning to F G. 6, an example routine 600 is depicted for operating a vehicle
including an electric drive in a mining environment, such as depicted in FIG. 5 . Such a routine
enables use of the electric drive's energy storage device to be optimized, and reduces the need
for operating an internal combustion engine in the mining environment.
[0042J At 602, the routine includes determining vehicle operating conditions. This
includes, for example, determining load to be carried, drilling requirements, ventilation and
emissions restrictions in the environment, planned route of travel, availability of external power
sources (e.g., position o catenary lines, scheduled power interruptions, etc.) and the like. At
604, it may be determined whether vehicle moving or tramming, that is, propulsion, is requested.
n one example, propulsion may be requested to move the vehicle (e.g., an ore cart) from a first
location i mining shaft to an alternate location, and/or to transport a mining load on the
vehicle from the first location to the alternate location.
[0043 l propulsion is requested, then at 604, the track gradient may be determined. At
608, it may be determined whether the track gradient is low (for example, lower than a .
threshold). If yes, then at 61 , the vehicle may be moved along the track using energy from the
system energy storage device, for example, the battery system. Specifically, the vehicle ay be
decoupled from a catenary line (thereby decoupling the vehicle from an external power source)
and a traction motor of the vehicle may be operated using power from t energy storage device.
In comparison, if it is not a ow gradient, then may be confirmed if the track has a high
gradient (for example, higher than a threshold) If so. then at 614, the vehicle may be coupled to
the catenary line (thereby coupling the vehicie o the external power source) and the traction
motor of the vehicle may be operated usi ng power from the external power source (for example,
a wayside power line). Additionally, and concurrently, the power from the external power
source may be used to charge the energy storage device.
[ 44 } irrespective of whether moving or tramming is requested or not, at 6 it may be
determined whether drilling is requested or not. Specifically, it may be determined if the
associated device, herein the drill, is to be operated or not. If not requested, the routine may end.
Else, at 8, it may be determined whether the external power source is available or not. I one
example, the external power source may not be available due to lack of wayside power lines
along a certain segment of track. n another example, even though a . power line is available,
external power may not be available due to scheduled and non-scheduled events where the
catenary line is tmpovvered. Such black-out periods may arise due to limitations on the capability
of the catenary line. Scheduled black-out periods may occur, for example, to allow for
maintenance operations on the catenary line and/or the power source. Unscheduled black-out
events may occur, for example, due to a grid power outage, an electrical short, damage to the
catenary line and/or malfunction of the power source. In one example, where the external power
source is a diesel engine, the scheduled black-out period may be to allow for maintenance of the
diese! engine, while an unscheduled black-out period ay occur due to the diesel engine running
out of fuel.
| 045| f an external power source is available, then at 620, the vehicle may be coupled to
the catenary line. Alternatively, if it was already coupled, it may remain coupled to the catenary
line. The vehicle's associated device, herein drill, is then powered using energy from the
external power source. comparison, if the external power source is not available, then at 622,
the vehicle may be decoupled from the catenary line. Alternatively, if it was already decoupled,
it may remain decoupled from the catenary line. The drill is then powered using energy from the
energy storage device.
[0046) While operating the drill at 620 and 622, it may be determined at 62 and 626,
whether a power boost is requested. n one example, a power boos may be required during a .
drilling operation to accelerate the drilling time, and/or whe drilling through harder materi al f
a power boost not required, the routine may end a power boost s requested at 624, then at
628, the power provided to the drill by the external power source is boosted with additional
power from the energy storage device. In comparison, if a power boost is requested at 626 (for
example, if the energy storage device is power-limited or running low on energy required for the
drilling operation), then at 630, the vehicle is coupied to the catenary l e an power provided to
the drill by the energy storage device is boosted with additional power from the external power
source. As such, at. bot 628 and 630. the combined (boosted) energy .from the energy storage
device and the external power source is greater than the power available from either of the
energy storage device or the external power source.
047) In this way, during first condition, when the vehicle is in a moving or tramming
mode, the propulsion system of th vehicle is powered with the energy storage device, while
during a second condition,, when the vehicle in a functional mode, the vehicle is coupled to the
external power source through the catenary line, and the external power source is used to power
the associated device of the vehicle and recharge the energy storage device. During a third
condition, when the vehicle is in a bridge mode an power is unavailable from the external
power source, the associated device is powered with the energy storage device. Alternatively,
during a fourth condition, when a larger amount of power i requested, the associated device is
powered using combined energy from the energy storage device and the external power source,
the combined energy greater than the power available fro either of the energy storage device or
the external power source. As such, during the first condition, the vehicle is moving, while
during the second, third and fourth conditions, the vehicle may be stationary.
]ΌQ4 | While the depicted example is elaborated using a drill as the associated device, it
will be appreciated that the energy storage device may also be used to operate one or more
auxiliary loads, such as additional pumps and drills. Thus, during a fifth condition, for example,
when the vehicle is handling fluids inside a mine shaft, the energy storage device may be used to
power a fluid handling pump coupled to the vehicle, the fluid handling pump including one or
more of an air pump and a water pump for moving air and/or water into or out of the mine shaft.
[0 49] Now turning to FIG 7, it shows another example routine 700 for operating a vehicle
including an electric drive n a mining environment, such as depicted in F G. 5 . Specifically, the
routine determine the operating mode of the vehicle based on the vehicle's operating conditions,
and optimizes use of the vehicle's energy storage device in the mining environment accordingly.
[ 0 J At 702, a at 602 the vehicle's operating conditions ay be determined. A
controller may determine the vehicle's operating mode based at least on the estimated vehicle
operating conditions. In addition, the vehicle's operating mode may be determined based on
input recei ved from a vehicle operator.
005 At 704, it may be determined whether the vehicle is in moving or tramming mode.
f yes, then at 706, the vehicle may be decoupled from the catenary line and the vehicle's
propulsion system (e.g., traction motors) ma be powered using power from the o -board energy
storage device. f the vehicle is not in a moving/tramming mode, then at 70S, it may be
determined whether the vehicle is in a functional mode. In one example, the vehicle may be in a
functional mode if drilling is requested f the vehicle is in a functional mode, then at 710, the
vehicle may be coupled to the catenary line and the vehicle associated device, such a a drill,
may be operated using power from the external power source. Additionally while the vehicle is
coupled to the external power source via the catenary line, the energy storage device may be
recharged using power form the external power source.
[ 052 If a functional mode is not confirmed at 708, then at 2, it may be determined if the
vehicle is in a bridge mode. As such, a bridge mode may be confirmed if an external power
source is not available., for example, d e to scheduled o unscheduled power interruptions f
yes, then at 7 14, the vehicle may be decoupled from the catenary line and the vehicle's
associated device, such as the drill, may be powered using energy from the energy storage
device. If the vehicle is not in a bridge mode, then at 716, it may be determined whether the
vehicle is in a boost mode n one example, a boost mode may be confirmed when additional
power i requested (for example, an amount of power greater than a threshold). If the boost
mode is confirmed, then at 718, the vehicle may be coupled to the external power source via the
catenary line and the drill may be operated using power from both the external power source and
the energy storage device.
o
[00531 At 720, it may be determined whether the vehicle is in fluid handling mode. n one
example, a fluid handling mode may he confirmed when a fluid (e.g., water or air) is to be
pumped in or out of the vehicle's environment (e.g., the mining shaft) f confirmed, then at 722,
the vehicle may b decoupled from the catenary line and the fluid handling pump may be
powered using energy fro the energy storage device n the mining embodiment, the fluid
handling pump may include one or more of an air pump and a water pump for moving air and/or
water into or out of a mine shaft f the fluid-handling mode is not confirmed, the routine may
end.
[00541 be appreciated that F GS. 6 and 7 illustrates only some of the possible
operating modes and options possible in a mining vehicle configured w th an electric drive
system. As elaborated w h reference to FIG. 9, still other operational modes may be possible
wherein a controller selects one or more of th external power source (via the catenary line), the
vehicle's engine, and the energy storage device to propel the vehicle, operate the drill, and/or
charge the energy storage device. As such, the various operational modes enable the vehicle to
have greater operational flexibility when operating in a mining environment. Specifically, itenables
operation of the vehicle to be quickly adjusted in response to ventilation requirements,
availability of wayside power, engine conditions, and battery conditions, with reduced
interruption of vehicle operation.
[0055J n this way, b using an energy storage device tha is selectively couplable to an
external power source via a wayside catenary line, the need to operate an Internal combustion
engine as the source of moving power or drilling power is substantially reduced in vehicles
operating in environments where the use of such engines is restricted.
[00561 This written description uses examples to disclose the invention, including the best
mode, and also to enable a person of ordinary skill in the relevant art to practice the invention,
including making and using any devices or systems and performing any incorporated methods.
The patentable scope of the invention is defined by the claims, and may include other examples
that occur to those of ordinary skill in the a rt . Such other examples are intended to he within the
scope of the claims if they have structural elements that do not differ from the literal language of
the claims, or if they include equivalent structural elements with insubstantial differences from
the literal languages of the claims. Moreover, unless specifically stated otherwise, any use of the
terms first, second, etc., do not denote any order or importance, but rather the terms first, second,
etc. are used to distinguish one element from another.
CLAIMS:
. An eleciric drive for a vehicle, comprising:
a motor capable of propelling the vehicle; and
an energy storage device coupled to the motor, and selectively coup! bl to a catenary
line, wherein the catenary line is capable of supplying electrical power to the vehicle and to the
energy storage device, and
wherein the vehicle includes a mining device that s operable o be powered by energy
from one o more of the catenary line and the energ storage device.
2 . The electric drive of claim 1, wherein the energy storage device is hermetically sealed to
prevent contact of a flammable gas with an interior volume of the energy storage device.
3 . The electric drive of claim 2, wherein the energy storage device is selectively operable in
one or more operational modes, the operational modes comprising:
powering the motor to propel the vehicle while the motor is decoupled from the catenary
line;
boosting the motor while the motor is coupled to the catenary line;
operating the mining device while the mining device is decoupled from the catenary line;
and
boosting the mining device while the mining device is coupled to the catenary line.
4 . The electric drive of claim 1, wherein the energy storage device includes one or more of
lead-acid, nickel cadmium, lithium ion, and nickel metal hydride battery systems.
5. The electric drive of claim 1, wherein the energy storage device is a sodium metal halide
battery system.
6 . The electric drive of claim 3, wherein the energy storage device is coupled to the motor
through a first inverter, a d is coupled to the mining device through a second, dif erent inverter.
7 A mining apparatus., comprising:
propulsion system including a motor;
a associated device;
an energy storage device; and
a control system with computer readable instructions for:
during a first moving mode, powering the propulsion system using the energy
storage device; a d
during a second functional mode, powering the associated device using energy
from an external power source while charging the energy storage device using energy
from the externa! power source
S. The mining apparatus of claim 7. wherein during the second functional mode, the mining
apparatus i ot moving.
9 . The mining apparatus of claim 7, wherein the associated device includes one or more
drills.
10. The mining apparatus of claim 7, wherein the associated device includes one or more of a
conveyor, dump, bolter, scoop, and chopper.
. The mining apparatus of claim 7, wherein the control system further includes instructions
for a third bridge mode, during which energy from the external power source is not available,
and the associated device is powered using energy from the energy storage device.
12 . The mining apparatus of claim , wherein the control system further includes
instructions for, during a fourth boost mode, during which the associated device is powered using
energy from the energy storage device and the external power source, the powering during the
fourth mode larger than the powering during the second or third mode.
13. The mining apparatus of claim 12, wherein during the second and fourth modes,
providing power from the external power source includes coupling the apparatus to the external
power source via a catenary line, and wherein during the first and third modes, providing power
fro the energy storage device includes decoupling the apparatus from the catenary line.
14. A method of operating a vehicle including a hermetically sealed energy storage device, a
propulsion system, and an associated device, comprising:
during a first condition, powering the propulsion system with the energy storage device;
during a second condition, powering the associated device and recharging the energy
storage device using an external power source, the vehicle coupled to the external power source
through a catenary line;
during a third condition, powering the associated device with the energy storage device;
and
during a fourth condition, powering the associated device using combined energy from
the energy storage device and the external power source, the combined energy greater than the
power available from either of the energy storage device or the externa! power source.
15. The method of claim 14, wherein the first condition includes the vehicle operating in a
moving or tramming mode, wherein the second condition includes the vehicle in a functional
mode, wherein the third condition includes the vehicle in a bridge mode wherein power in
unavailable from the external power source, and wherein the fourth condition includes the
vehicle operating n a boost mode wherein extra power is requested.
16. The method of claim 14, wherein during the first condition, the vehicle is moving, and
wherein during the second, third, and fourth conditions, the vehicle is stationary.
. The method of claim 14. further comprising,
during a fifth condition, wherein the vehicle is operated in a fluid handling mode inside a
mine shaft, powering a fluid handling pump coupled to the vehicle using the energy storage
device, the flu handling pump including one or more of an a r pump and a water pump for
moving air and/or water into or out of the mine shaf .
18 The method of claim 16, wherein during the first and third condition, providing powe
fro the energy storage device includes decoupling the vehicle from the catenary line.
. A method of controlling a vehicle including a hermetically sealed energy storage device,
a traction motor, and a drill, comprising:
operating the vehicle through a region of a first, lower gradient while propelling the
vehicle using energy from the energy storage device and charging the energy storage device
using energy fro an external power source; and
operating the vehicle through a region of a second, higher gradient while coupling the
vehicle to he externa! power source via a catenary line and propelling he vehicle using energy
from the external power source.
20 The method of claim 1 , wherein propelling the vehicle using energy from the energy
storage device includes operating the traction motor using energy from he energy storage
device, and wherein propelling the vehicle using energy from the external power source includes
operating the traction motor using energy from the external power source.
21. The method of claim 19, wherein propelling the vehicle using energy from the energy
storage device cludes decoupling the vehicle from the catenary line.