U.S. patent application number 09/815388 was filed with the patent office on 2002-09-26 for method and apparatus for distributing electric power.
This patent application is currently assigned to Xantrex International. Invention is credited to McMillan, Glenn.
Application Number | 20020135232 09/815388 |
Document ID | / |
Family ID | 22904306 |
Filed Date | 2002-09-26 |
United States Patent
Application |
20020135232 |
Kind Code |
A1 |
McMillan, Glenn |
September 26, 2002 |
Method and apparatus for distributing electric power
Abstract
An electric power distribution system includes a first power
distribution apparatus for distributing power to individual load
circuits from a main power source and a second power distribution
apparatus adjacent the first apparatus. The second panel has a
base, an electric power distribution conductor supported by the
base for providing electric power from the alternate electric power
source and a load circuit selector site on the base and is operable
to supply power from the main electric power source and the
electric power distribution conductor to a signal-controlled
selector installed at the load circuit selector site.
Inventors: |
McMillan, Glenn; (Belcarra,
CA) |
Correspondence
Address: |
CHRISTENSEN, O'CONNOR, JOHNSON, KINDNESS, PLLC
1420 FIFTH AVENUE
SUITE 2800
SEATTLE
WA
98101-2347
US
|
Assignee: |
Xantrex International
|
Family ID: |
22904306 |
Appl. No.: |
09/815388 |
Filed: |
March 22, 2001 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
60239918 |
Oct 13, 2000 |
|
|
|
Current U.S.
Class: |
307/23 |
Current CPC
Class: |
H04B 2203/5466 20130101;
H01H 89/06 20130101; H01H 71/524 20130101; H04B 2203/5445 20130101;
H01H 2300/018 20130101; H01H 50/326 20130101; H04B 3/54 20130101;
H04B 2203/5441 20130101 |
Class at
Publication: |
307/23 |
International
Class: |
H02J 009/00 |
Claims
What is claimed is:
1. A method for distributing electric power, the method comprising
distributing electric power from an alternate electric power source
to a plurality of selector sites and supplying electric power from
said alternate electric power source or from a main electric power
source to at least one load circuit, through a signal-controlled
selector at at least one of said plurality of selector sites.
2. The method of claim 1 wherein distributing comprises conducting
current on an electric power distribution conductor in proximity to
said plurality of selector sites.
3. The method of claim 2 further comprising supporting said
electric power distribution conductor and said plurality of
selector sites on a base.
4. The method of claim 3 further comprising supporting a plurality
of signal lines on said base to permit said plurality of signal
lines to carry control signals to respective signal-controlled
selectors.
5. The method of claim 4 further comprising providing at least one
control signal for controlling at least one signal-controlled
selector.
6. The method of claim 5 further comprising supporting on said base
a controller operable to produce said at least one control
signal.
7. The method of claim 5 further comprising supporting on said base
a connector for receiving said control signals from a remotely
located controller.
8. The method of claim I further comprising providing overload
current protection to said load circuit when electric power is
supplied to said at least one load circuit from said alternate
electric power source.
9. The method of claim 1 further comprising providing a plurality
of overload current protection mounting sites in proximity to
corresponding selector sites to provide for mounting and connection
of overload protection devices in series with said alternate
electric power source and respective selector sites.
10. An apparatus for distributing electric power to a load circuit
from a main electric power source and an alternate electric power
source, the apparatus comprising: a base; an electric power
distribution conductor supported by said base for providing
electric power from said alternate electric power source; and a
load circuit selector site on said base and operable to supply
power from said main electric power source and said electric power
distribution conductor to a signal-controlled selector installed at
said load circuit selector site.
11. The apparatus of claim 10 further comprising the
signal-controlled selector installed at said load circuit selector
site, wherein said signal-controlled selector is operable to
selectively connect the load circuit to said main electric power
source or to said electric power distribution conductor in response
to a control signal.
12. The apparatus of claim 11 further comprising a signal line
supported by said base for carrying said control signal to said
signal-controlled selector.
13. The apparatus of claim 12 further comprising a controller for
providing said control signal for controlling said
signal-controlled selector.
14. The apparatus of claim 13 wherein said controller comprises a
processor circuit supported by said base.
15. The apparatus of claim 13 further comprising a means supported
by said base for receiving said control signal from a remotely
located controller.
16. The apparatus of claim 10 further comprising at least one
overload current protection mounting site on said base and
associated with said load circuit selector site to provide for
mounting of an overload current protection device.
17. The apparatus of claim 16 further comprising an overload
current protection device mounted at said overload current
protection mounting site.
18. The apparatus of claim 17 wherein said overload current
protection device comprises a circuit breaker.
19. The apparatus of claim 10 wherein said base supports a
plurality of overload current protection mounting sites associated
with separate respective load circuits.
20. The apparatus of claim 19 further comprising a plurality of
signal-controlled selectors, each one being installed in a
respective load circuit selector site.
21. The apparatus of claim 20 further comprising a controller for
providing respective control signals to said plurality of
signal-controlled selectors.
22. The apparatus of claim 20 further comprising a connector for
receiving respective control signals, and signal lines on said base
for communicating said control signals to said plurality of
signal-controlled selectors.
23. The apparatus of claim 20 further comprising a plurality of
overload current protection mounting sites on said base, each
overload current protection mounting site being associated with a
respective load circuit selector site to provide for mounting of a
respective overload current protection device in said each overload
protection mounting site.
24. The apparatus of claim 23 further comprising a plurality of
overload protection devices, each one being installed in a
respective overload current protection mounting site.
25. An electric power distribution system comprising: a first power
distribution apparatus for distributing power to individual load
circuits from a main power source; and a second power distribution
apparatus adjacent said first apparatus, said second apparatus
having a base, an electric power distribution conductor supported
by said base for providing electric power from an alternate
electric power source and a load circuit selector site on said base
and operable to supply power from said main electric power source
and said electric power distribution conductor to a
signal-controlled selector installed at said load circuit selector
site.
26. An apparatus for distributing electric power to a load circuit
from a main electric power source and an alternate power source,
the apparatus comprising: a base; means supported by said base for
providing electric power from said alternate electric power source;
and means for supplying power from said main electric power source
and from said means supported by said base to a device on said base
for selectively supplying power from said main electric power
source or from said means supported by said base to said load
circuit.
27. The apparatus of claim 26 wherein said base includes a printed
wiring board and said means for supplying power comprises traces on
said printed wiring board.
28. The apparatus of claim 27 further including mounts connected to
said traces and arranged to form a selector site to facilitate
mounting of a signal-controlled selector thereon.
29. The apparatus of claim 27 further including a plurality of
mounts and traces arranged to form a plurality of selector sides on
said base to facilitate mounting of a plurality of respective
signal-controlled selectors.
30. The apparatus of claim 29 further comprising means for carrying
control signals to said plurality of respective signal-controlled
selectors.
31. The apparatus of claim 30 further comprising means for
providing at least one control signal for controlling at least one
signal-controlled selector.
32. The apparatus of claim 30 further comprising means for
receiving said control signals from a remotely located
controller.
33. The apparatus of claim 26 further comprising means for
providing overload current protection to said load circuit when
electric power is supplied to said load circuit from said alternate
electric power source.
34. The apparatus of claim 26 further comprising means for mounting
overload current protection devices on said base for protecting
respective load circuits.
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application claims the benefit of U.S. Provisional
Patent Application Ser. No. 60/239,918, filed Oct. 13, 2000.
BACKGROUND OF THE INVENTION
[0002] 1. Field of Invention
[0003] This invention relates to methods, apparatus and systems for
distributing electric power, and for distributing electric power to
a load circuit from main and alternate electric power sources.
[0004] 2. Description of Related Art
[0005] Increasing numbers of critical appliances or devices such as
computers, alarm systems or heating/cooling systems are being
employed in commercial buildings and residences. Many of these
appliances and/or devices require a continuous supply of electrical
power. Most residential and commercial buildings are wired for AC
electric power supplied only from a single utility electric power
source. In some areas this utility electric power source can be
unreliable or expensive. Consequently, it is desirable to be able
to use alternate sources of electric power as backup electric power
sources to ensure a continuous supply of electric power or as less
expensive electric power source alternatives.
[0006] Commonly, alternate electric power sources such as
generators and inverters, for example, are wired to separate
circuits and separate outlets or are used as alternate electric
power sources to a conventional AC electric power distribution
panel normally supplied with electrical power from an electric
power utility. Connecting individual appliances to separate
circuits or separate outlets is impractical, as a user would have
to connect each appliance to an appropriate outlet to receive
electric power from either the main electric power source or the
alternate electric power source, as required. Many generators, for
example, have built in AC receptacles by which they supply electric
power but can only accommodate a few appliances.
[0007] Alternatively, individual devices or appliances can be wired
directly to a separate electric power distribution system which may
be connected to a transfer mechanism operable to receive electric
power from two AC electric power sources. This is often done where
critical load circuits are to be backed up by an alternate AC
electric power source. These load circuits are usually removed from
the main electrical panel and wired into a secondary sub-panel.
This sub-panel is then powered through a manual transfer switch or
automatic transfer switch for controlling electric power supplied
to the entire secondary panel. When AC electric power failure
occurs from one source only those devices wired to the separate
electric power distribution system are operable to draw electric
power from the other AC electric power source.
[0008] The main disadvantage of the above system is that every
device or appliance needing backup electric power must be wired to
this special, separate electric power distribution system, which
may require substantial re-wiring of circuits throughout a
building. This has the additional disadvantage of limiting the
locations the devices or appliances can be placed, and necessitates
circuit rewiring when devices or appliances are moved.
[0009] In addition, sourcing an entire AC electric power
distribution panel with an alternate source requires the ability to
switch large currents which mandates the use of expensive high
current switching equipment. In conventional high current systems
which provide for switching of an electric power distribution panel
feed from a conventional high current AC source to an alternate
source, transfer speeds are relatively slow because of the large
ampere ratings of the relays required to be actuated. Furthermore,
the distance required between contacts of this type of transfer
device increases proportionately to the current carrying capacity.
Sub-panel transfer relays are relatively large and very slow,
making them impractical for sub-panels supplying computers and
process control equipment.
[0010] What would be desirable therefore is a simple way of
extending an electric power distribution panel to provide for an
alternate power supply to selected circuits, without rewiring of
load circuits and without requiring high current switching
capacity.
SUMMARY OF THE INVENTION
[0011] The above problems are addressed by providing a method for
distributing electric power involving distributing electric power
from an alternate electric power source to a plurality of selector
sites and supplying power from the alternate electric power source
or from a main electric power source to at least one load circuit,
through a signal-controlled selector at at least one of the
plurality of selector sites.
[0012] Distributing electric power may include conducting current
on an electric power distribution conductor in proximity to the
plurality of selector sites, where a base may support the
conductor, the plurality of selector sites and a plurality of
signal lines to carry control signals to respective
signal-controlled selectors.
[0013] The method may also include providing at least one control
signal for controlling at least one signal-controlled selector and
supporting, on the base, a controller operable to produce the at
least one control signal or a connector for receiving control
signals from a remotely located controller.
[0014] The method may also include providing overload current
protection to the load circuit when electric power is supplied to
the load circuit from the alternate electric power source. This may
be facilitated by providing a plurality of overload current
protection mounting sites in proximity to corresponding selector
sites to provide for mounting and connection of overload protection
devices in series with the alternate electric power source and
respective selector sites.
[0015] In accordance with another aspect of the invention there is
provided an apparatus for distributing electric power to a load
circuit from a main electric power source and an alternate electric
power source. The apparatus includes a base, an electric power
distribution conductor supported by the base for providing electric
power from the alternate electric power source, and a load circuit
selector site on the base and operable to supply power from the
main electric power source and the electric power distribution
conductor to a signal-controlled selector installed at the load
circuit selector site.
[0016] The apparatus may further include the signal-controlled
selector, which may be operable to selectively connect the load
circuit to the main electric power source or to the electric power
distribution conductor, in response to a control signal.
[0017] The base may have a plurality of selector sites to support a
plurality of signal-controlled selectors and the base may support a
plurality of signal lines for carrying control signals to
respective signal-controlled selectors at respective selector
sites.
[0018] The apparatus further may include at least one overload
current protection mounting site on the base and associated with
the at least one selector site to provide for mounting of an
overload current protection device for, protecting the load circuit
when electric power is supplied to the load circuit from the
alternate electric power source. The overload current protection
device may be mounted at the overload current protection mounting
site and may include a circuit breaker.
[0019] The apparatus may further include a signal-controlled
selector operable to be received in the selector site for
selectively connecting the load circuit to the main electric power
source or to the electric power distribution conductor in response
to a control signal.
[0020] The apparatus may further include a controller for providing
at least one control signal for controlling the signal-controlled
selector. The controller may include a processor circuit supported
by the base, for example. The apparatus may also or alternatively
include a connector supported by the base for receiving the control
signals from a remotely located controller. Or the apparatus may
include a wireless receiver or transceiver for receiving at least
one control signal for controlling the signal-controlled
selector.
[0021] In accordance with another aspect of the invention, there is
provided an electric power distribution system including a first
power distribution apparatus for distributing power to individual
load circuits from a main power source, and a second power
distribution apparatus adjacent the first apparatus, the second
apparatus having a base, an electric power distribution conductor
supported by the base for providing electric power from an
alternate electric power source and a load circuit selector site on
the base and operable to supply power from the main electric power
source and the electric power distribution conductor to a
signal-controlled selector installed at the load circuit selector
site.
[0022] Using specific embodiments of the invention provided herein,
the base may be mounted right beside an existing main electric
power distribution panel, permitting load circuit wires to simply
be removed from the main panel and moved a few inches (centimeters)
to connect to the base. Thus, rewiring of load circuits is
relatively simple and does not require a separate remotely located
subpanel as with conventional alternate supplies. Through use of
the embodiments of invention described herein, the need to
completely rewire panels in existing buildings to supply circuits
with alternate sources of electric power is removed. In addition,
the need for a secondary sub-panel in new construction is removed.
Furthermore, use of such embodiments provides for safer
installation by having only one place within a given building to
disconnect a load from AC electric power and by ensuring that
backfeed of electric power into the utility or into the alternate
source cannot occur. Power transfer occurs at the load circuit
level and therefore switching is done on currents of lesser
magnitude which enables smaller components to be used in the
selectors, such smaller components having less mass and requiring
less spacing than higher current apparatus, resulting in faster
transfer speeds, rendering embodiments of the invention more
suitable for use with computers and process control equipment.
[0023] Other aspects and features of the present invention will
become apparent to those ordinarily skilled in the art upon review
of the following description of specific embodiments of the
invention in conjunction with the accompanying figures.
BRIEF DESCRIPTION OF THE DRAWINGS
[0024] In drawings which illustrate embodiments of the
invention,
[0025] FIG. 1 is a pictorial representation of a system for
distributing power according to a first embodiment of the
invention; and
[0026] FIG. 2 is a pictorial representation of an alternate power
distribution apparatus shown in FIG. 1.
DETAILED DESCRIPTION
[0027] Referring to FIG. 1, a system for distributing electric
power is shown generally at 100. The system 100 includes a first
power distribution apparatus, which in this embodiment includes a
main electric power distribution panel shown generally at 102 for
providing electric power to individual load circuits from a main
power source such as an electric utility supplier. The apparatus
further includes at least one alternate power distribution
apparatus such as apparatus 104 or 106 respectively, each for
distributing electric power to at least one load circuit from the
main electric power source, through the conventional main electric
power distribution panel or from an alternate electric power source
such as a power conversion device or generator, for example. The
power conversion device may include an electric power inverter, for
example. In this embodiment, the apparatuses 104 and 106 are
located on opposite sides of and adjacent to the main electric
power distribution panel 102. Thus, close proximity of apparatuses
102, 104 and 106 makes it easy to simply transfer load circuit
terminations from the main electric power distribution panel 102 to
new terminations on the alternate power distribution apparatuses
104 and 106, as will be seen below. This eliminates the need to
rewire or splice existing load circuits and ensures that all
electrical power distribution connections are located at or
adjacent to the main electric power distribution panel 102,
maintaining the focus of electric power distribution at or about
the main electric power distribution panel and desirably not
distributed about a premises. The apparatuses 104 and 106 could
however be located away from the main electric power distribution
panel 102, but this would usually require splicing extensions onto
the load circuits.
[0028] Referring to FIG. 2, in this embodiment, each apparatus such
as apparatus 106 includes a base 110, an electric power
distribution conductor 112 supported by the base for providing
electric power from the alternate electric power source, and
includes a load circuit selector site such as site 130 on the base
operable to supply power from the main electric power source and
the electric power distribution conductor 112 to a
signal-controlled selector 114 installed at the load circuit
selector site.
[0029] In this embodiment, the base 110 is formed from a printed
wiring board on which is printed a plurality of copper electric
power distribution conductors or traces, two of which, 112 and 116,
act as an electric power bus 118 for supplying electric power from
an alternate source. Each electric power distribution conductor 112
and 116 may be connected to a separate phase (line) of an AC
supply, for example. This facilitates use with multiple phase
supplies, such as three-phase supplies, for example. Referring to
FIG. 1, neutral conductors of the supply are connected to a neutral
bus 127 of the main electric power distribution panel 102. The
copper traces 112 and 116 may be terminated at one end of the base,
in a first set of first and second terminals, such as screw
terminals 120 and 122, to which wires (not shown) from the
alternate electric power source may be connected to receive
electric power from the alternate electric power source. The copper
traces 112 and 116 may also be terminated at an opposite end of the
base 110, in a second set of screw terminals 121 and 123 to
facilitate connection to an adjacent apparatus such as apparatus
125 shown in FIG. 1, to facilitate expansion of the electric power
bus 118, through the installation of additional apparatuses of the
type described herein.
[0030] In this embodiment, the base 110 has a plurality of selector
"sites" including the first selector site 130 and a second selector
site 132 at which respective signal-controlled selectors, such as
114 and 115 can be installed to control the supply of electric
power to respective associated load circuits. These sites may
provide relay sockets, for example, or direct solder connections
for mounting relays or other switching devices which may act as
signal-controlled selectors operable to selectively connect the
load circuit to the main electric power source or to the electric
power distribution conductor 112 and 116, in response to a control
signal.
[0031] To do this, referring to FIGS. 1 and 2 each selector site
130,132 has a main terminal 134 for receiving electric power by
means of a wire 135, from a circuit breaker 136 housed in a circuit
breaker receptacle of the main electric power distribution panel
102. Each selector site 130 and 132 also has an output terminal 138
for terminating a conductor such as a wire 143 for providing
electric power to a load circuit connected thereto.
[0032] Referring to FIG. 2, in this embodiment each selector site
130,132 further includes traces 141,143 on the base 110 from the
main terminal 134 and the output terminal 138 respectively,
terminated in pads or mounts 140 and 142 respectively, for
connection thereto of a first contact and a common contact,
respectively, of a signal-controlled selector 114 or 115 mounted at
the site. In a direct current (DC) system, each electric power
distribution conductor 112 and 116 may be connected to a separate
or the same DC system pole, such as a positive (+) terminal and the
opposite pole such as the negative (-) terminal may be connected to
the neutral bus 127. It would even be possible to connect an AC
power source to one conductor 112, for example and a DC power
source to the other conductor 116, for example to produce a hybrid
system.
[0033] Each selector site 130,132 also includes a pad or mount 144
for connection to a second contact of the respective
signal-controlled selector 114 or 115 and includes a trace 145
leading to a pad or mount 147 of an overload current protection
mounting site 146 on the base and associated with the selector site
to provide for mounting of an overload current protection device
148. A suitable overload current protection device 148 may include
a fuse or circuit breaker element, for example, which serves to
protect an associated respective load circuit connected to the
output terminal 138 from excessive currents supplied by the
alternate source. Overload current protection is provided when the
load circuit is supplied from the main source, by the circuit
breaker 136 in the main electric power distribution panel 102.
[0034] Each selector site 130,132 also has control and common coil
pads or mounts 150 and 152 for terminating control and common coil
contacts, respectively, of a signal-controlled selector 114 for
supplying electric power to a coil 154 thereof. Circuit traces 156
and 158 extend from these pads and trace 158 is, in this
embodiment, terminated at a contact 160 of a connector 162
supported by the base 110, while trace 158 is connected to a common
coil pad of each site and is ultimately terminated at a common
contact 164 at the same connector 162. Other circuit traces 166
similar to traces 156 extend from respective control pads of
respective selector sites 130,132, to respective contacts on the
connector 162.
[0035] The coils 154 or actuators of respective signal-controlled
selectors 114 are controlled by signals received on respective pins
of the connector 162. Thus, the traces 156 and 158 act as a
plurality of signal lines which are supported on the base 110 for
carrying control signals to respective signal-controlled selectors
114.
[0036] The coil 154 of any given signal-controlled selector 114
controls a contactor 168 thereof to selectively electrically
connect the common contact pad 142 to either the first contact pad
140 or the second contact pad 144 to cause the common contact pad
to be supplied with electric power from either the main electric
power source or the alternate electric power source. Thus the coil
154 acts to selectively connect the load circuit to the main
electric power source or to the electric power distribution
conductor 112 in response to a control signal.
[0037] Signals for controlling respective signal-controlled
actuators 154 may be provided by a controller 170, such as a
microprocessor control circuit, which selectively provides control
signals for energizing respective signal-controlled selectors
114,115 to determine whether or not a respective corresponding load
circuit is supplied with electric power from the main electric
power distribution panel 102 or from the alternate source supplying
electric power to the electric power distribution conductor
112.
[0038] In this embodiment, the controller 170 is mounted separate
from the apparatus 106 and is operable to provide control signals
through the connector 162. The controller 170 may be a circuit on a
power inverter, for example, located remotely from the electric
power distribution system 100. It should be noted that in an
alternate embodiment the controller may be mounted on the base 110
such as shown in broken outline at 172, and the control signal
traces, or a subset thereof, may be connected directly thereto in
which case the connector 162 may not be needed.
[0039] In another alternate embodiment, the connector may be
replaced with a wireless receiver or transceiver for receiving
wireless signals from a remote device for controlling the signal
controlled selectors 114,115. Such a wireless receiver or
transceiver may be of the type provided under the trademark
BLUETOOTH.TM. owned by Telefonaktiebolaget L. M. Ericsson of
Sweden.
[0040] The apparatus 106 provides a convenient way of extending a
main electric power distribution panel 102 into an electric power
distribution system 100 which is operable to supply electric power
from either a main electric power source or an alternate electric
power source. As shown in FIG. 1, simply by mounting the apparatus
106 adjacent to an existing main electric power distribution panel
102, wires from load circuits leading to the existing electric
power distribution panel may easily be disconnected and connected
to the output terminals 138 of respective selector sites 130,132 of
the apparatus 106. In addition, typically only two wires, a line
and neutral wire, may be required to be run from the alternate
electric power source to the apparatus 106 in order to distribute
electric power to each of the selector sites 130,132 through the
electric power distribution conductor 112. Thus the apparatus may
quickly be installed and operational in a relatively short period
of time.
[0041] As stated above, the control signals, no matter how they
originate or are received, determine which load circuits are to be
supplied from the main or alternate power sources. This easily
facilitates selective load sharing between power sources and may be
used to isolate loads being supplied from different sources. In
areas subject to brown-outs, for example, essential appliances may
be supplied from the main or utility power source while luxury
appliances may be supplied from the alternate supply.
[0042] While specific embodiments of the invention have been
described and illustrated, such embodiments should be considered
illustrative of the invention only and not as limiting the
invention as construed in accordance with the accompanying
claims.
* * * * *