Note: Descriptions are shown in the official language in which they were submitted.
CA 02658236 2009-01-16
WO 2008/010801 PCT/US2006/028085
1
ELECTRICAL ENERGY SOURCE
TECHNICAL FIELD
The present invention relates to electrical energy sources and more
specifically to
substantially autonomous portable electrical energy sources.
BACKGROUND ART
Mobile power supplies are often needed where electric appliance operation is
desired
during emergency situations when the public utility grid is unavailable. Since
practically
every electrical appliance requires 110V AC electricity to operate, the mobile
power supply
must have some means of generating alternating current within an acceptable
voltage range.
One commonly used method involves the use of a fuel-driven generator. Such
generators, however, are bulky and lack the versatility of portability in
automobiles, convoys,
boats, and the like. Fuel driven generators may also pollute and emit carbon
monoxide,
which can be dangerous to users, especially in close quarters.
An alternative and more compact form of power source is based on solar energy
that
is converted to electrical power through the use of solar panels in
conjunction with
converters, inverters, and the like. However, these systems may be costly,
while being
unworkable during inclement weather conditions.
Inverters are also available to invert low direct current ("DC") voltage such
as around
8-12 volts to alternating current ("AC") mains voltage levels, of around 110-
120 volts.
However, such inverters may be costly while rapidly depleting the DC voltage
source.
Additional drawbacks of conventional power supplies and/or generators,
notwithstanding the fact that they may be capable of providing a maximum AC
output of
1000 Watts of power on a continuous operation of 12 hours, is that these
primarily gasoline
operated generators emit fumes and polluting hydrocarbons during their
operations. Noise
levels of such generators may be excessive, ranging from 47 dBA at 1/4 load up
to 57 dBA
and higher at full load.
Moreover, power inverter systems having 12 Volts from a battery and converting
the
12V to a 115 Volt AC household power, with output power at 2500-Watts
continuous with a
5000-Watts surge has been known to electrical engineers and the public for
years.
Japanese Patent No. 57-193,977, published November 29, 1982 to Tokunaga
Kiichi,
et al., appears to show DC current control device that controls for output of
maximum electric
CA 02658236 2009-01-16
WO 2008/010801 2 PCT/US2006/028085
power, a secondary battery, arid an inverter when converting DC power from
solar batteries,
but does not appear to disclose the present invention as claimed.
Similarly European Patent No. 0-372-933, published June 13, 1990 to Nishi
Kazuo, et
al., appears to disclose providing an appliance with a power supply in the
form of a solar
energy accumulator, but does not appear to disclose the present invention as
claimed.
Additionally, Japanese Patent No. 3-74,147, published March 28, 1991 to
Yamamoto
Yoshiro, et al., appears to show a system having solar cell and diesel engine
driven generator
charging means for charging a storage battery, but does not appear to disclose
the present
invention as claimed.
Moreover, many of the aforementioned related art systems generally require an
external 12 Volt battery source to operate, while outputting only AC Power.
Also, installation is generally required by hardwiring AC output to the
battery, while
the inverter may need mounting as well. When connected to a vehicle, boat, or
RV, the
aforementioned systems may require constant running of the engine to provide
the 12-Volt
power source, and thus severely limit the portability when operated with a
vehicle.
Moreover, it is not uncommon for such a unit to require forty or more hours to
fully
charge its internal rechargeable battery. It would be desirable, however to
provide a power
inverter system having a predetermined minimum DC internal/portable voltage
supply that
can produce 2500-20000 watts AC and that has a reduced amount of time to fully
charge its
internal rechargeable battery system.
Thus, an electrical energy source solving the aforementioned problems is
desired.
DISCLOSURE OF THE INVENTION
This disclosure is directed to an electrical energy source housed within an
enclosure.
The energy source includes at least two batteries that are electrically
connected in series, and
at least one battery charger and at least one DC to AC power inverter. The
energy source
also includes a DC driver circuit with an input that is connected to the
batteries so that the DC
driver circuit has an output that is responsive to battery current detected at
the DC driver
circuit input. The energy source also includes a DC output stage with a DC
driver that
receives an input and a low voltage, high current output. The DC output stage
is provided to
perform a DC to DC conversion to reduce the voltage produced by the two
batteries
connected in series. The DC output stage DC driver receives an input from a
connection to
the DC driver circuit output. The connection is provided to control the DC to
DC conversion.
CA 02658236 2009-01-16
WO 2008/010801 PCT/US2006/028085
3
The low voltage, high current output of the DC output stage is connected to an
input of a DC
filter. The first output of the DC filter is connected to an input of the at
least one DC to AC
power inverter. A second output of the DC filter is connected to a DC filter
input of a control
unit. A switch control output of the control unit is connected to an AC
control switch in
order to provide a switch control signal. The AC power output of the DC to AC
power
inverter is connected to the AC control switch. The AC control switch has the
capability to
connect and disconnect the AC power output of the inverter to and from an AC
outlet port
that is responsive to the switch control signal from the control unit. The AC
outlet port is
disposed on the enclosure. The control unit has an AC input from an extenlal
source. The
control unit has the capability to route the external source AC input to the
charger for a
predetermined charging time period. A timer is operably connected to the
charger and to the
control unit in order to set the predetermined charging time period. An on/off
switch powers
up the electrical power source, and alternatively powers down the electrical
power source.
In operation, when the electrical energy source is powered up aiid delivering
electrical
power to a load, the control unit, responsive to a change in the second output
from the DC
filter, interrupts electrical power delivery from the electrical energy source
to the load and
initiates recharging of the batteries for a predetermined time determinable by
the timer. After
the predetennined time the control unit reestablishes power delivery to the
load by the
electrical energy source.
BRIEF DESCRIPTION OF THE DRAWINGS
Fig. 1 is an envirornllental, perspective view of an electrical energy source
according
to the present invention.
Fig. 2 is a front view of the electrical energy source, according to the
present
invention.
Fig. 3 is a side view of the electrical energy source, according to the
present
invention.
Fig. 4A is a rear view of the electrical energy source, according to the
present
invention.
Fig. 4B is a rear view of the electrical energy source with the rear panel
removed,
according to the present invention.
CA 02658236 2009-01-16
WO 2008/010801 PCT/US2006/028085
4
Fig. 5A is a front view of a non-wheeled, portable version of the electrical
energy
source, according to the present invention.
Fig. 5B is a side view of a non-wheeled, portable version of the electrical
energy
source, according to the present invention.
Fig. 5C is a rear view of a non-wheeled, portable version of the electrical
energy
source, according to the present invention.
Fig. 5D is a front view of a non-wheeled, portable "battery pack" version of
the
electrical energy source, according to the present invention.
Fig. 6A is a block diagrammatic view of the electrical energy source,
according to the
present invention.
Fig. 6B is a block diagrammatic view of the electrical energy source including
regeneration apparatus, according to the present invention.
Fig. 6C is a block diagrammatic/schematic view of the electrical energy
source,
according to the present invention.
Fig. 6D is a schematic view of the charging/regeneration circuit of the
electrical
energy source, according to the present invention.
Figs. 6E-6F are a schematic diagram of electrical energy source according to
the
present invention.
Fig. 7A is a front view of the regeneration assembly, according to the present
invention.
Fig. 7B is a top view of the regeneration assembly platform, according to the
present
invention.
Fig. 8 is a diagrammatic view of the electrical energy source with interface
cable to a
residential fuse panel, according to the present invention.
Fig. 9A is a schematic view of the of the electrical energy source connected
to a house
wiring breaker panel, according to the present invention.
Fig. 9B is a continuation of the schematic view of Fig. 9A, according to the
present
invention.
Fig. 10 is a schematic view of the inverter section of the electrical energy
source,
according to the present invention.
Fig. 11A is graphical load line diagram of the electrical energy source out of
service
from the utility service, according to the present invention.
Fig. 11B is a graphical load line diagram of the electrical energy source in
service
without utility service, according to the present invention.
CA 02658236 2009-01-16
WO 2008/010801 PCT/US2006/028085
Fig. 11C is a graphical load line diagram of the electrical energy source in
service
while using utility service for charging, according to the present invention.
Fig. 11D is a graphical load line diagram of the electrical energy source
during
portable operations without any utility service, according to the present
invention.
5 Fig. 12A is a front view of an alternative low-profile wheeled embodiment of
the
electrical energy source, according to the present invention.
Fig. 12B is a side view of an alternative low-profile wheeled embodiment of
the
electrical energy source, according to the present invention.
Fig. 12C is a bottom view of an alternative low-profile wheeled embodiment of
the
electrical energy source, according to the present invention.
Fig. 12D is a top view of an alternative low-profile wheeled embodiment of the
electrical energy source, according to the present invention.
Fig. 12E is a sectional front view of an alternative low-profile wheeled
embodiment
of the electrical energy source, according to the present invention.
Similar reference characters denote corresponding features consistently
throughout
the attached drawings.
BEST MODES FOR CARRYING OUT THE INVENTION
The current invention includes a portable enclosure defining battery bank,
monitor
and control, along with AC inverter and regeneration coinpartments. Operation
of batteries,
AC inverters and regeneration unit is coordinated by a monitor and control
unit. During
operations under a load, the batteries supply an input to AC inverters, which
in turn provide
AC power to the load.
When the batteries have discharged to a predetermined level, the load is
removed
fi-om the AC inverters, and a dedicated inverter is used to power the
regeneration unit which
recharges the batteries. Once the batteries have been recharged, the AC
inverters are again
made available to the load. The system does not use an internal combustion
engine, and thus
does not require fossil fuels for operation.
As shown in Figs 1-5D, the present invention is a multipurpose electrical
power
source that may be configured in various fixed and portable embodiments
including wheeled
versions, and noii-wheeled versions that have grab handles for lifting. As
shown in Fig. 1,
the energy source 105 may be connected to power up an electrical load such as,
e.g. lamp A.
CA 02658236 2009-01-16
WO 2008/010801 PCT/US2006/028085
6
A preferable cabinet size of the energy source may be 30"W x 36"L x 42" H. The
energy
source enclosure comprises a fiont chassis support 107 and two enclosure
wheels 110 to the
rear of the chassis support 107. The wheels 110 may be comprised of a hard
rubber
composition or similar durable material capable of rolling over a variety of
surfaces. An
interface panel 115 is provided as an inset to a front panel 210. The
interface panel may
include AC output receptacles 117 and an on/off switch 123. The single manual
on/off
switch 123 provides fully automatic operation once the unit 105 is turned on.
Additionally an auxiliary input receptacle 119 and an auxiliary output
receptacle 121
are provided for easy access. DC output meter 125 is provided so that a user
can inonitor the
DC output of the present invention. Referring to Figs 1 and 6C, a source meter
127 is
provided so that a user can monitor the voltage level of the input to
inverters 605, 609, and
612.
A chassis handle 205 may be included to provide assistance in moving the
device
from place to place. As shown in Fig. 3, a side panel 303 may include
ventilation ports 305.
As shown in Fig. 4A, a rear cabinet panel 405 may include an input cooling fan
410 and an
exhaust cooling fan 415. As shown in Fig. 4B, the enclosure is braced by
diagonal upper
fraine braces 420 and vertical lower frame brace 425. The enclosure is divided
into a first
compartment floor 430a, a second compartment floor 430b, a third coinpartment
floor 430c
and a fourth compartment floor 430d. Compartment floors 430a through 430d
house
respectively, first bank of energy storage cells 435a, second bank of energy
storage cells
435b, first and second charging units 440a, 440b, and, first and second banks
of inverters
445a, 445b.
As shown in Fig. 5A, the non-wheeled, portable version of the electrical
energy
source 105 has a carrying handle 505, a front panel 507, an interface panel
515, a power
switch 523 and support rests 525. AUX2 OUT port 521 and AC outlet 517 are also
provided.
Fig. 5B shows a side view of the non-wheeled portable version of the
electrical
energy source 105. A side panel 503 has ventilation ports 305. Carrying
handles 505 are
disposed along corners where the side panels meet a top paiiel. Panels are
fastened together
with fasteners 531 which may be rivets, screws, and the like.
As shown in Fig. 5C, AUX IN 119 and AUX OUT 121 receptacles are disposed on
the rear panel of the non-wheeled, portable version, according to the present
invention.
Cooling fan 410, exhaust fan 415, 15A circuit breakers 535 and ventilation
louvers 305 are
also disposed on the rear panel of the einbodiment shown in Fig. 5C.
CA 02658236 2009-01-16
WO 2008/010801 PCT/US2006/028085
7
In the "Battery Pack 24V" embodiment of the present invention, as shown in
Fig. 5D,
a charge/boost switch 580 is included on front panel 507. Reset button 585 is
provided to
reset system electronics. Within interface panel 515, an AUX IN port 519 is
provided, an
AUX2 OUT port 521 is also provided. The entire enclosure is supported by
rubber support
rests 525.
As shown in Figs 12A - 12E, the electrical energy source 105 may be provided
in an
alternative wheeled embodiment 1205. The alternative wheeled embodiment 1205
has a
lower profile "open cage" chassis in which the interface panel 1207 and
inverter section 1220
are mounted on an upper level of the chassis and the batteries 1210 are
mounted on a lower
level of the chassis.
A bottom panel 1229 of the unit 1205 may have cable outlets 1230 for
connection to
batteries 1210. As shown in top view Fig. 12D, heat sinks 1235 are disposed
laterally across
the unit inverter section 1205. A mesh guard 1240 is provided to protect
cooling fans and
power transistors below the guard. Referring to Figs 12A and 12E, the
interface panel 1207
is disposed laterally across the unit 1205 to provide easy access to
electrical monitoring,
switches, fuses and 1/0 sockets.
As shown in Figs 6A - 6C, at least one sealed battery pack 601 is used as an
input
power source. The battery pack 601 preferably comprises 12.5 V DC batteries
within the
pack 601 wired in series to provide approximately 25 VDC. Current capacity may
be added
by wiring additional series configured 12.5 VDC batteries in parallel with the
pack shown in
Fig. 6C. Preferably, individual batteries of the pack 601 may be comprised of
spiral celled
batteries. The battery pack 601 has outputs to a final DC output stage 603. DC
output stage
603 preferably comprises an array, i.e., plurality QI - Q10 of Insulated Gate
Bipolar
Transistors (IGBT array) in order to provide a high current controlling
capability along with
the capability to limit, i.e., regulate the DC output voltage to a voltage
that is compatible with
subsequent stages of the system 105, e.g., 12.5 - 14 VDC. For example, a 3KW
system 105
using the final DC output stage 603 can provide approximately 580 amperes for
use by
subsequent stages of the system 105.
As shown in Fig. 6E, output stage 603 may use ordinary, e.g., 2N5055, high
speed
switching transistors Q2, Q6, Q7 Q8, Q9, Q10, Q1l, Q12, Q13, Q14, instead of
the
aforementioned IGBT array. Additionally, DC filter 604 may comprise parallel
electrolytic
capacitors C6 - C9, each capacitor having approximately 36,000 MFD and rated
at
approximately 35 volts DC. Moreover, one of the output lines to the Final DC
output stage
603 has an intervening electrical connection to DC control drive, i.e., DC
driver circuit 602
CA 02658236 2009-01-16
WO 2008/010801 PCT/US2006/028085
8
which in turn has an electrical output to the iinai .u", output stage 603. DC
control drive 602
provides voltage regulation at the output of final DC output stage 603. As
shown in Fig. 9,
DC control drive 602 may comprise a Darlington pair of transistors, such as Q1
and Q2,
having a set-point determined by potentiometer R12. Alternatively a voltage
regulator
module, such as e.g., an LM 7812, may be used to accomplish the voltage
regulation function
of DC control drive 602. Additionally there is a bi-directional electrical
interface between
the battery pack 601 and a charging circuit 606.
The charging circuit 606 has at least one bi-directional electrical interface
to a timer
607. Additionally, an ammeter 614 may be connected between the charging
circuit 606 and a
series resistor R614 to ground in order to provide monitoring capability of
the charging
process. Auxiliary input port 611 has an output that is electrically connected
to the charging
circuit 606. Charging voltage from auxiliary sources such as solar power
generators,
automotive/marine power sources, and the like may be provided by a connection
to auxiliary
input port 611.
As shown in Fig. 6E-6F, the charging circuit 606 may comprise a plurality of
half-
wave bridge rectifier modules having center-tap transformer primary windings
and that can
produce approximately 14.7 volts DC each. Diodes D5 - D12 in the bridge
rectifiers may
have a 1KV, 50A capacity. The transformers T1 -T2 may have a 110 V AC primary
and a
35A 13.8 volt secondary.
Charger input may be fused with, e.g., fuses F5 and F6, each having a 20A
current
rating. Charging circuit 606 may be provided with a low voltage input and a
high voltage
input. The low voltage input is activated by switching the 110 VAC input from
end-to-end
priinary leads to end-to center-tap primary leads of transformers T1 and T2.
Charger output
may also be fused with, e.g., fuses F7 and F8 which are shown to each have a
60A current
rating. The current capacity of the charging circuit 606 allows for faster
recovery time while
charging the battery packs 601. AC input to the charging circuit 606 is
switched by the timer
607.
Timer 607 has at least one bi-directional electrical interface to control
circuit 608.
The control circuit 608 has an AC input from a public utility line.
Additionally, the control
circuit 608 has an input from the DC filter 604. The final DC output stage 603
has an
electrical output to the DC filter 604. Thus, operational conditions of the DC
filter 604 when
being subject to output voltage from the final DC output stage 603 may be
monitored by the
control circuit 608 in order to determine when charging circuit 606 should be
activated under
timing control of timer 607 to charge battery pack 601.
CA 02658236 2009-01-16
WO 2008/010801 PCT/US2006/028085
9
As shown in Fig. 6C, the DC filter 604 can include capacitors Cl and C2 in
parallel
with filainent resistance of lamp Ll in series with filter resistance R1 in
order to provide a
sufficient RC time constant that can smooth any transient output from DC
output stage 603.
Fuses Fl and F2 protect the system 105 from any over-voltages that may be
developed at the
output of DC filter 604. Lamp L2 is provided for a visual verification that a
voltage is
present at output of DC filter 604.
The DC filter 604 output is electrically connected, i.e., routed to inputs of
AC
inverter/filters, 605, 609, 612. At least one of the inverterlfilters 605,
609, 612 may have a
bi-directional electrical connection between an inverter/filter output and an
input of an AC
control switch 610. A plurality of outputs of the AC control switch 610 supply
AC output
voltage to a plurality of loads, i.e., devices to be operated, such as
appliances, lights,
computers, air conditioners, televisions, shop lights, hand drills, power
saws, office
equipment, and the like. DC output stage 603 can make up to 580 amperes or
more available
to the AC inverters/filters 605, 609, and 612. Due to the high current output
of the electric
power source 105, many of the aforeinentioned appliances and equipment can run
simultaneously under power supplied by the power source 105. AC
inverters/filters 605, 609,
612 may be off-the-shelf conunercially available units having adequate
ventilation and
capable of providing AC voltage in the 110 - 120 V range when supplied with
the regulated
DC voltage provided by final DC output stage 603.
Alternatively, inverter stages 605, 609, and 612 can be built up, utilizing
the design
shown in Fig. 10. Both off-the-shelf and custom designs of the
inverter/filters are preferably
capable of providing a pure sine wave output for compatibility with a wide
variety of loads.
According to the present invention, voltage output from final DC output stage
603 to primary
windings of transformers T1, T2, and the like, may be converted to pulses by
switching
action of a crystal controlled timing circuit 1005, such as the crystal
controlled timer IC 555
in operable communication with power switching transistors Ql - Q4 shomi in
Fig. 10.
Moreover, in the embodiment shown in Fig. 10, transformers T1, T2, and the
like,
have a 12 VDC primary with center-tap, and a 110VAC secondary. Capacitors Cl,
C2 are
preferably .OOluF and rated at 1KV. Capacitor C3 is 3600 MFD and rated at 35
VDC. Lamp
Ll is a 110 VAC pilot lamp for AC output indication. Transistors Q1 - Q4 are
preferably
2N3055 or equivalent,
Diodes D1 - D4 are 50A, 1KV rated. Resistor R1 is a 10KS2 potentiometer and
rated
at 2 Watts. Resistor R2 is 10K52 and rated at 2 Watts. Resistor R3 is 45S2 and
rated at 2
Watts. Clock crystal is approximately 200Mhz. The inverter shown may provide
CA 02658236 2009-01-16
WO 2008/010801 PCT/US2006/028085
approximately 400W output. Identically configured stages, such as the
aforementioned
described inverter shown in Fig. 10, may be added to provide additional power
output.
As shown in Fig. 6C, the AC control switch 610 comprises a single pole double
throw
(SPDT) relay of which one half of the switching circuit is utilized (only one
pole is connected
5 to inverter outputs). The relay coil of control switch 610 is energized by
the control circuit
608 when power from the energy source 105 is ready to be delivered to the
load.
Additionally, as shown in Fig. 6B, at least one AC inverter/ filter 605 may
have a bi-
directional electrical connection to a regeneration device 625. The
regeneration device 625,
which may comprise, inter alia, e.g., an AC generator or an AC alternator, has
a plurality of
10 electrical connections to the bi-directional connection between the timer
607 and the control
circuit 608.
When directed by the control circuit 608 (such as, e.g., when a predetermined
low
inverter output voltage threshold has been reached), the regeneration device
625 can feed
battery charging current to the battery pack 601 via timer 607 and charging
circuit 606 at the
same time control circuit 608 commands the AC control switch 610 to remove
inverter power
from the load. As shown in Figs 7A - 7B, components of the regeneration device
625 are
mounted on a stable base plate 705 via mounting slots 710 and 715. Components
of the
regeneration device 625 may comprise a 110 VAC electric drive motor 640 having
a
mechanical output that is connected via belt 637 to a reduction gear
set/sheave set 642. A
110 - 120 V AC power generator 645 has a rotor that is connected via belt 639
to a high
torque output of gear set/sheave set 642.
Preferably, as shown in Fig. 7A, the ratio of the sheave diameters may be 4:1,
the
larger sheave being connected to the power generator 645 in order to provide a
torque
mechanical advantage. As shown in Fig. 6D, electrical output (110 - 120 VAC)
of the
generator 645 is connected to charging circuit 606. As shown in Figs 6B and
6D, 110 - 120
VAC from the inverter/filter 605 is applied to power up the drive motor 640.
As the drive
motor 640 rotates, increased torque is applied through the gear set/sheave set
642 to cause the
power generator 645 to rotate, which produces voltage required by the charging
circuit 606 to
recharge the battery pack 601.
Preferably, the mechanical advantage provided by gear set/sheave set 642
allows
drive motor 640 to operate while demanding substantially less current from
inverter/filter 605
than the battery pack charging current produced by power generator 645 in
combination with
charging circuit 606. A preferable rotational speed of the drive motor drive
shaft is
CA 02658236 2009-01-16
WO 2008/010801 PCT/US2006/028085
11
approximately 1,700 RPM. A preferable rotational speed of the power generator
drive shaft
is approximately 2,200 RPM.
The aforementioned RPM speeds are exemplary only, and it should be understood
that preferable RPM speeds of both drive motor 640 and power generator 645 may
vary
depending on the electromechanical characteristics of the drive motor 640 and
power
generator 645, as well as the specific mechanical configuration of gear
set/sheave set 642.
As shown in Figs 8, 9A, and 9B, when the electrical energy source 105 is
connected
to house wiring via breaker panel interface cable 805, the control circuit 608
can direct the
control switch 610 to switch the house wiring from the utility supplied AC
source to the
electrical energy source 105, and vice versa. Power switching may be
accomplished
manually via switch SW1 or automatically via low voltage detector IC1 which is
capable of
sending a signal from the control circuit 608 to the control switch 610 to
switch the house
wiring from the electrical energy source 105 to the utility source in response
to a low voltage
condition within the electrical energy source 105. Advantageously, the robust,
preferably
hardwired logic of control unit 608 requires no software code for operation,
thereby
increasing reliability of operation.
Additionally, a programmable dial up module 905 may be included and connected
to
a phone service line 910 to provide status notification of the electrical
energy source 105 to a
reinote location.
As shown in Figs 11A - 11D, power load line 1110 vs load time duration 1120
demonstrates high regulation of voltage and amperage output over a wide range
of operating
conditions, from no load, full utility mode, full service load with no utility
service, utility
service charging mode, and field use with no utility service charging
available.
As shown in Figs 12A - 12E, an alternative low profile wheeled embodiment 1205
may coinprise an interface panel 1207, a battery compartment housing a battery
1210, and an
upper compartinent housing an inverter 1220. The bottom of the lower
compartment may
have battery cable outlets 1230. Upper compartment 1220 may have exposed heat
sinks
1235, and a mesh guard 1240 covering cooling fans and power transistors.
Advantageously, solar panel technology can be added or used with the present
invention for redundancy purposes. An automobile charging system may also be
used to
recharge the energy source 105. Although preferably the aforementioned
regeneration device
625 may be used to keep the battery pack 601 charged. Once the batteries have
been
recharged, the AC inverters 605, 609, and 612 are again made available to the
load.
CA 02658236 2009-01-16
WO 2008/010801 PCT/US2006/028085
12
The system is environmentally safe because it does not use an internal
combustion
engine, and thus does not require fossil fuels for operation. The system is
designed to
provide voltages selectable from 110 - 220 volts and to provide power to loads
which
demand up to 3000 watts, and, as shown in Fig. 2, via appropriate interface
receptacles at
interface panel 115 may also provide DC power simultaneously with AC power.
The electric power source 105 of the present invention may be used like a
conventional Uninterruptible Power Supply (UPS), or it may be used as the
primary power
source having predetermined time periods within which the load is switched to
the utility
(mains) source during a recharging cycle. The electric power source 105,
according to the
present invention provides power while emitting lower noise levels than the
combustion
engine counterpart power sources.
It is to be understood that the present invention is not limited to the
embodiment
described above, but encompasses any and all embodiments within the scope of
the following
claims.
