Note : Les descriptions sont présentées dans la langue officielle dans laquelle elles ont été soumises.
CA 02469768 2008-02-18
DESCRIPTION
Title oCthe Invention
A Methodology for timo-chiitrfng electrical grid cnergy rtonqumption to
optimize cost rate aud grid lo=rd
lcvcl
Background to the invention
Electrical power genaration, tramsmi.vsioit, and distribution systems muyt all
bc cnginccrcd to withstand peak
detnand. Recent growth in consumption, couplcd with cap.'n:ity constraints in
cartain gcttcration and distribution
facilitics havc strained the ability of utility grids to nta:t peak demands.
Lk-rcguiation initiatives create furthcr
pricing fluctuations that arc passed on to consumcrs. Sornc juri.tidictions
are moving towards timc of day based
etterg,y rates to rcReet generation and/or dcli.-cry costs during peak
intcrvals and to encourage conservation
during peak demand intc-rvRls.
Thcrc is an abundanLv of prior art that providws a means for scnsing utility
grid failure and switching ovcr tc-
altcrnatc cncrg_y sourccs, inctudinl; stored cncrgy. Mtuiy ofthe.se prior art
cxamplw-5 also provide for a
"swndhy", "auxiliary", or "pony^ distribution p,Mc) which is scparatc from a
main distribution panel and which
allows for sc:lcetcd loads to bc puwered by an altcrnatc cnergy source rather
than powering the entire main
distribution panel and its Icacis.
At Icast one particular itcm of prior art de.ticribes the use of capacitors as
a storage medium fisr utility cncra
during low deniand pcriod4, and using that stored energy during peak demand
periods by discharging it at or
near the point ofconsumption. "fhe basis on which this swrage facility is
chargcd and discharged is lcfl up to a
"controllcr" which may or may not use a number of potcntial means tu make such
dccisions. 'l'his storage
facility is describcd as being locatW cither at a point of cx>nsumption or at
a gcncration or distribution point. At
least onc othcr example of prior su't describes a massive concrete f'lywhccl
which is used to storc utility grid
oncrgy during non-peak load, and which is used to gencrdte electrical power
during peak load.
Still olh4Y prior art sceks to reduce utility wnwmpi ion costs by managing
load levels. puwcr distribution,
load shedding and so forth. Somc such invcntions propose claboratc
consumpticin prediction mcthw.l.r uy govern
whether or whcn to switch to stored energy wfiilc others rely on a mcana af
communication with the utility to
detcrmine instantancous rates for consumption of utilic.y rcuwrces and usc
thtet, information to rcgulatc charge
and discharge cycles.
The present invention relatcs to a means for providing eneW to houc:x and the
likc at a cast lower than ptrak
demand r4tes from a utility by going olT-grid" during pcak energy times and
supplying the dcmand from storcd
energy or an altcrnate enerby sc>uree. An onc=rl;y storage device is
replenished frotn thc utility during off-peak
dcmand times whcn rates are morc favourable. A control method is described
which provides for a timc of day
and calendar b.-.;ed schodulc of events as wcll as system evcnts. manual
events and cxternal events which
rcgulatc charbc and di5chargc cycles for an clcctriusl cnergy storagc tacility
locatcd at the point of consumption_
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Summary ot'thc invention
It is an object of this invention to providc :u:c;css to lower cost otl=grid
energy altcrnativcs to a house or the
like during times when the cost of consumptinn of utiGty resourc.cx is
relatively high, or when the utility grid is
operating at high deniand.
It is another object of this invcntion tc- provide the ability to storc
cncrl,ry frum the utility grid during times
when the cost of consumption of utility resources is relativcly low.
In one embodiment of this invention (Fig i ) utility powcr [ I] is connected
to a main distribiit.ion panel 131
through a switch unit [2]. Also conncctcd to thc switch unit is a D.C. to A.C.
invcrt.Lr [4] which is in turn
conncctcd te> a battery plant [5]. The battery plant may c:onsiyt of one or
more re-charbcablc clcetrieal batteries.
Thc bat.tery plant may :slso be connected to a batt.cry charger [6]. A control
unit [7] communicates with switch
unit, D.C. to A.C. inverter, battcry plant, battury charg4r, user intcrface
unit 113,1, and machine interface unit
[14[.
In dnother embodimcnt Ut'the invention (Fig 2), the system is as dcsc:ribed
above except that am auxiliary
dititrihution pancl [9] is connected to switch unit [2], and anothcr }witch
unit [8J is used to connect or disconnmt
main distribution panel (9] from utility grid
In another embodimcnl. (Fig 3) ot'the invcntion the system may be as described
abovc only with a tuel cell
pl;tnt [ 101 in place ot'the battery plant [51 and fuel cell fucl [111 in
place of the battc:ry charger [61.
In another emb<xlirnent (Fig 4) of thc invcntion the system may be as
doscribcd above only with a capacitor
plant in place of thc battery plant and :s capacitor charl;c controller in
plac.c of the battery chargcr.
In all embodiments of the invcitticm, the control unit monitors system events,
extcrnal events, manuat evcnts,
and schcdulul events, and cnmmunicatcs with the various othcr unit, in the
syst.cm ac.urrdingly. 'l'hc switx;h unit
connects a utility grid to an auxiliary and/or tnain disttibution pancls
during times o{'non-pe:ak utility dcmand. A
schedulcd cvcnt (eg. the beginning of a daily peak dentand intcrvai), or an
extcrnal event (eg. a utility grid
failure) may causc the control unit to signal the switch units to disconnect
the distribution panels front the utility
grid and to connect the C)_C_ to A.C. invcrter throuGh to thc main or
auxiliary distribution pancl. Power is
supplied to the distribution panel from a stor.il;c tacility through the D.C.
to A.C. inverter and the switch unit.
At such timc as an appropriate systcm cvcnt occurs (cp;. the storage facility
becomes dcplctcul), or when an
appropriate schcduled evont c>ccurs (eg. whcn the aveiagc peak utility demand
intcrval is ovcr, or whcn the cost
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ol'consuming utility resources is relatively low), the control unit msy
hil;nal thc switch unit to disconnect the
D.C. tu A.C. inverter from the distribution panel and tg) connect the utility
grid to the clistributinn pancls. At
somc time during non peak utility demand, or when the cost of consuming
utility rcsourccs is relatively low, a
schcdulcd cvcnt m.ry causc thc control unit to enable the replenishment of the
storage facility_ When thc storagc:
facility becomes replenished, or when the storage facility is G;tu.ved to
discharge through thc D.C. to A.C.
inverl.cr, a syst.cm evcnt may cause the control unit to cause storage
facility replenishment to eease.
Th4 control unit ecwrdinatOS the operation of the switch units, thc O.C. to
A.C. invcrtcr, and the storage
facility replenishmcnt_ Thc control unit may also monitor storage
facilitystatus and respond to other ink:rnal or
cxlcmal cv4nt.w_ 7'he control unit is also drivc:n hy scht:clulc.~,f cwcnts
that arc prog:unmcd into it and which causc
actions to he executed on the basis of time of day and a calendar. The
controller may also be driven by manual
cvcnt.% that may be initiated throuO a user interfaee or a machine interfaee,
or by other input.v and cvcnt% threwgh
the machine intcrfacc.
Brief description of the dr-awings
In the drawings, like rcfarcncc numcrals r.,-prcx.-nt likc c:ompon4rrt.,I.
Figure 1 is a block diagram of an cmbodirncnt of ttiG invention wheYCin ;r
baucry plz;nt s-nd [).(,, to A.C.
invcricr are sufficicnt to satixfy the neccLt ot'the entirc main distribution
panel and its loads.
l+ig;urc 2 is a block diagram of another embodimcnt of thc invention whcrein
an auxiliary distribtition pzincf
[9] supplies basic cnergy ncods during times whcn thc systcm is switc;hcd away
frotn the utility grid.
T'igure 3 is a block diagram of anothcr cmbodimcnt of the invention which is
identical to that shown in Figure
2 with the exception th;:l a fuel cell plant [ 10; is used instead of a
battery plant f5] and fucl ccl] fucl [ t 1] rcplac:Cs
battery charger [b].
Figun; 4 in a block diagram of anothcr cmbodimcnl of thc invention whcrc a
capacitor plant [15.1 scrvcs as the
storage facility and a capacitor plxnt ch:irKer [161 effcc:ts replenishment of
that storagc facility.
Figure 5 is a state diagram for a control process for managing the operation
of the syst.cm.
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Ucscniption of the preferred emlfodiment:e
f.)c.s4rigtiun ut S~titc m i:l4mcntc
lJtility Grid [ l J:
This systcin component consists of a utility company power linc which supplies
utility power to a wnsumcr.
For most residontial applic;,ations this would hc a 200 Amp 240 Volt servicc.
Switch Unit (2]:
In a residential application this elcmcnt contains a switch capable of
switching a 200 Amp 240 Volt utility
company power line, and a mcanx uf detec:ting whcther power is present on said
utility power linc irrespcctivc ol'
what position thc switeh may he in_ Functions performed by this unit includc
connecting to and ditic4)nnccting
from a utility grid (1), connecting te and disconnccting, from a D.C. to A.C.
invcrtcr (4), and monitoring utility
grid (I J 4latuy (cg. presence oi' power).
Main L)istribution Panel 131:
This is the main electrical distribution pancl in a house or the like. 71ie
function of this clement is to
distribute electrical power to varinus loads through circuit breakers.
D.C. to A.C. invcrtcr [41;
't'his clemcnt is comprised of a means of converting din:ct currcnt (D.C.)
battery power to altcrnating current
(A.C.) power suitablc for driving a distribution panel and its loads that
would normally receive power trom the
utilit.y grid. This component takcs storcd clcctricul cnc:rgy from a battery
plant 151 and produce5 altcrnating
current electrical power to supply a distribution panel (9].
fiattery Plant [5 J:
This is an arr:ry ot'c,ne or more electrical battcric+ that arc capable of
storing clectrical cnerJ,*y from a battery
ch;trg4r 161 and capable ofdispc:nsing electrical energy to a D.C. to A.C.
invcrter [41.
fiattcry Charger [6J:
7'his element is comprised ot'a means to convcrt cl4etrical power from a
utility or from an ex(crnsl gcncrator
tc- a D.C. level suitablc for charginb battery plant [5]. "t'hi, clcmant is
further compriscd of a mcans to sc:u:pt
utility powcr fnom a distribution panct, and a mcans to accept powcr from an
cxtereal generator. The battery
chsrger [b] distribulcs this energy to battery plant f 5] in a manner that
allows the battcry plant to sturc: that
energy for ful.urn u.sc.
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Control Unit (7):
'I'his element iy comprised of a computer processor, a non-volatilc cornputer
memory, a readable and writable
random access mcmory (RAM), interiace circuitry which servcs as a mcans of
communicating with switch units
121 and (8] and D.C. tc) A.C. invcrtcr [4] and :aoragc facilitics [5], f 101,
or [ I S] and storage replenishment 161,
[ 1 11, or [161 and uscr intsrfacc unit [ 13] and tnachinc intertacc unit [
141, and som4 locaf power and control
circuitry and a control program that resides in non volatile mc:me>ry and runs
on the computer processor. 'I'hc
hardware used for this unit may bc ati.tic:mble.~d from corninercial off tho-
shclf clcrncnt.v that are tainiliar to anyone
skilled in the field.
'I'hiti elcmcnt performs thc following f'uncticxts:
The control unit monitors and opcrates switch units [2] and 131.
'l'he control unit further monitors and opi:rates battery charger [6] or
capacitor plant charger [ 161 or fuel cell
fucl [I I 1.
'I'hc control unit further monitors and operates D.C. to A.C. invcrtcr [4].
1'hc control unit further mc>nitprti battery plant [5 J status or fuel cell
plant [ 10] status or capacitor plant ] 15]
status.
'I'he control unit further monitom and resp.)nds to user intcrfac;u unit 113]
and machinc intcrfacc unit [ 141_
7'he control unit further monitors and respondti to dctined evcnts, a
dcsc:ription of which toltows.
l7Cl inttinns:
Storagc Unit Replenishmcret In:terv;:l: a scheduled timc uf d:sy during which
Utility Grid r,rtes nuny he
relatively low, and during which thc system will try to rceharge the storage
clcmcntti (efi. batteries,
capacitors, and thc like)_ 11he beginning and encl of this intcrval arc
programmed in advance (cg, factory
default scttinl; or at installation time) either through a machinc interface
unit or a u5c:r interface.
Schedulcd Uff Grid Interval: a schcdulod time of'day during which [Itility
Grid rates may bc relatively
high, and during which the systcm will switch ti-om the laltility Grid to
locally storcd clcetrical power. 'Mc
beginning and cnd of this intorval are programmed in advanc:c (ct;- factory
default sc(ting tir at installation
time) either through a machinc intcrface unit or a user interl"acc.
Schedulcd Fvvnts, which arc Cvents th;tt can bc prot;rarnmed into the control
unit based on timc of day,
day of weck, or calcndar iiatc_ Examp'cs of such cvcnts include but are not
limitcxi to:
o 7'()D-RrP: Time oi' D:iy changcs from bciiig NOT within Storage tlnit
Rcplenishmcnt intcrval tu
being within Storage tJnit Rcptcni,hmcnt intcrval. This evcnt is triggcrcd in
the Control Unit by
comparing currant day and time with the pre-programmcd Storage [Jtiit
Replenishment interval.
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o TUU-NKE:I': ''Fime of Day ehang4.e from being within Storage (Jnit
Rcplenishmcnt intcrval to being
NU'(' within Storage Unit Replenishment interval. This cvcnt is tri}gcred in
the Control [Jnit by
comparing current day and timc v-ith thc prc-prrtgrammed Storage Unit
Replenishment intcrval,
o 7'OU-C)FF(.iCtC): Time of Day chaslges t?om bcing NU'I' within Schcdulcd
C)tY'Grid ina:rval tc) being
within Schedulcd Off Grid intcrval, This event is triggered in the C'ontrol
Unit by cump=arin[; aurnc.~nt
day and tin-c with the pre-nrogran:med Schedulcd Off Grid interval.
n TQD-NOFFC)RU: 'I'imc of Uay chsxngcv from being within :ichcdulcd UffCirid
interval to beinf;
NO7' within Schcdulutl Of'1'CCrid 'utterval_ 't'his evant is trig;cnxi in the
Control Unit by comparing
Currc:nt day and timc with thc prc-prn%rarnmed Scheduled Off Grid intcrval,
Manually induced events, which arc cvenL. that are caused by manual
intcrvcntian through the user
intLrfac:e unit or machinc intcrTac:e uniL h:atamples of such cvcnts include
but are not limitcd to:
o MAN-ItI:P: A signal has bccn rccoivcd frcxn the iJser Intorfacc or Machine
Interface requesting tha
Controller to begin charging ttic battery or storage elcmcnt from the [Jtility
(3rid.
o MAN-NRi:P: A signal has been rcx:cived from the User Interface or Machine
Interiace requesting the
Controller to stop charging the battery or storage elcmcnt frpm the [Jtility
(;rid.
o MAN-UFFGRi): A signal has bcx=n rc:cciv4d from the User Interface or Machine
Interface requesting
the Controller to switch thc sytitent power source from thc tJtility Grid to
the battery or storagc
element.
o MAN-NOFFGRD: A signal has becn received from thc User lntertace or Machine
lntcrfac:c
requesting the Controller to switcli thc,,;y+wm power sourcc from the hattery
or stor.tgc clcmcnt lo
the [Jtiliry Grid.
o MAN-Sl-1UTi)C)WN: A signal ha-; ba:n received from the Uxr Interface or
Machinc [ntcrl';sec
rcqucsting the Controller tn switclt the systcm to a Shut Down state.
o MAN-CLEAR; A signal has been reccival f"mm the User Intcrfau: or Machine
Interfacc requesting
that all Critical Faiiure indications be cleared.
System evcnt%, whieh are events that :Lre caused by a change in status of a
system clcnecnt or component.
'I'hcsc cvcnts may bc dctcctcd by any of a numlx:r of well known measurement
techniques outsidc thc
scope of this invention but which are wcll known by anyone skilled in the
f'weld_ i:xamples ot'such an
event include, but arc not limited to:
o BA'1'-0f?P: Remaining energy in battcry or stcx-age element has crossed a
pre-set threshold:md is
depleted.
c, l3l1'1'-1.(aW: Remaining cnera in battcryrr xtorage elemcnt h.ts crossed a
prc-sct threshold and is
approaching depletion.
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o SA'T-h'UC,: licmaininl; cn4rSy in battery or storage element has crosscd a
pru-yrrrt threshold and is
fuliy ch;irgvd.
o CRiTICAL-rAII.: Thc Contrc)ller has detected a critical system condition
which rcquires manual
intcrvcntiun. F-xamples of this includc but arc not limi" to battery or
storage olement tempcraturc
alarm, DC to AC invcri.cr ovcrltuaci, and the like.
Extc:ma.l eventr., which arc cvcnts that arx: external to the system. These
cvcnty may he detm-ted by any of
a rrumber of well known mca.yurement tcchniques outside the scope of this
invention but which arc wcll
known by anyone skilled in the ficlJ. F,xantpley of such an c-vent includc,
but an: not limitod to:
o CiRll}FAIL: '1'hc Utility Cirid which has been ablc to supply cleetrical
energy is no Ionbcr ablc to
supply electrical cnera to the syst.crn.
rs CCR1D-RFC: 'I'hc Utility Grid which has not. bccn ablc tcr tiupply
electrical cnorbry is now ablc ta
supply clccstrical cnerg,y to the syswin.
The control pmt;ram in the control unit Cxeeutes code which implcmvntti the
control process which i.
described in Figttrc S. The control pro$ram tiuther maintains a timc of day
clock and calcndar and a list of
wchcdulcd events. 'l'hc control program cxectatcs thc sic:quence of states in
Figure 5 as per defined events and the
tinte of day clock and calendar.
Switch Unit [8]_
In a residential application this clemcnt contains a switch c:apabic of
switching a 200 Amp 240 Volt utility
oumpany powcr lin4, and a mcans of dc.'tccting whothcr- power is present on
said utility Fxrwcr linc irrespa:tivc of
what position thc switch may bc in. Functions pcrfornrcd by this unit include
connecting to and disconnecting
from a utility grid [ 11, and monitoring utility grid [ I I s;atus (cg.
prescnce of powcr).
Auxiiiary Uistributiixk Panci [9]:
'I'his is srn clectrical distribution pattel which may he installed in a house
or the like to pruvidc scrzuate
clcctrical powcr for.i sulx,et ofalcctrical ioa4s on the premiu;ti. In the
embodimcnt: described hcrcin, thiv
distribution punel would manage the ktads that would he maintained during the
O['1'Grid states as described in
Figurc 4.
Fuel C':ell Plant [10[:
This clcment consists of a mcans of producing clcctrical powcr directly from a
contiumablc: fucl and may bc
corrrprised of onc or rttore such ecils etfntigvred in an :uray.
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Fuel Cell Fuel (1 1 1:
17iis component provides a means of storin6 fuel atsd a means ot'supplying
iucl to the fuci ecll. in a fiu:l ccll
plant [ 101.
1?mcrgency t;c.-nerator cunnect point 112]:
'rhiy element provides a means of connecting an external electrical generator
to the battc:ry charger unit. [t is
anticipated that this point may bc uscd during prolonf;cd utility grid 1;1 J
outages.
User Intcrfacc lJnit -131:
'I'his clcmcnt pruvidus a mcans for tnanua; communication with the control
unit, and it may be remotely
lcx:atcd f}om the control unit. Alarms and syr+tcm clcmcnt status may be
communicsttcd to;, usCr through this
unit. Further, a usar may prttgram ychcduled events into the control unit or
may induce manual events t[irough
this clcmcnt.
Machine Intertace Unit (141;
This clcinent providcs a means for connecting the control unit to another
computer. '1'his may be used to
provide an improved user interface, pcrform ::yxtcm di.)l;notitic and text,
pmvidc enhanced support firr u.~r
maintenance, or to nctwork the systcm to otb.:r systen-, and control. This
facility inay also bc uscd to cffcct
control program updates and install thcni into the control unii.
Capacitor Plant I 151:
11iti elentent consists of a mcanti of sutrin- electrical enerfry in a
capacitor and niay bc compriscd of onc or
more such capacitors c,tmfrgured in an array.
Capacitor E'larit Charger 116]:
flriti clcmwnt is comprised oC,i mc ans lu convert electrical power from a
utility or frotn an cxternal ;;enerator
to a D.C. lovci suitablc for Charging capacitoi plant (1 ti], This clcntont is
f'urthcr compriscd ot'a means to ac:ccpt
utility power 1cont a distribution panel, and a mcsns to accept power from an
external gcncrator. Thc eapacitor
plant charger [16,1 dist.ributc+ this energy to cupacitor plant [15] in Y
manner that allows the capacitor plant to
storc that cnurgy for future usc.
1'rcferred Rmbodinicnts
Rcfcnring to Figure 1, one cmbodimcnt of th4 invention includes a utility grid
i 1], a switch unit 121, a ntain
distribution panel 13 1, a[).C:. tn A.C. inverter 14J, a battcry plant 15], a
hattery charger 161, and a control unil 171.
Under normal operating conditions the switcli unit [2] connects the utility
grid [ 1] to thc main distribution panel
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13]_ During this time, and in this mtxie, the alntrol unit 171 niay activatc
the battery charger 16J and cause the
battery plant [5 J to be replenished_ At such timc as the control unit 171
rccogniics a sc:hedulcd event, a manually
inslut:CCl evenl, or an exl.crnal cvent (cl;. 111.ility grid failurc), thc
conirol unit [7] may cause the switch unit 121 to
disconnect the utility grid [I ] 1rom the distribution panel 131, and tc)
deaetivatc: thc bau,cry chargcr (61 if it is
activated, and to connect the I).C:_ tr) A.C_ imerfer (4] tc) t.he
distribution pancl 131. In this mode the battery plant
(5] discharges through the D.C. to A.C. inverter [4] and supplies the energ,y
nceds of the distribution pancl ]3]
for an interval of timc. At such time as thc ctmtrullcr rc-c:ognizcs anothcr
scEtedulod cvent, a rnanually inducod
cvcnt, :- sytitcrn event (eg. deplcted battery) or an external event (eg.
utility grid recovered 1'rnn, f=rilun:), thc
control unit [7] may cause thc switch unit [21 to disconnect the O.C. to A.C.
invcrtcr 141 from thc distribution
pancl 131 and (c) Conncct, the utility grid [1] tl) the distribution partel
[3].
Rcfcrring to higurc: 2, another cmbodimant of the iaver)tion includes a
utility grid ],1 ], a switch unit ]2], a
main distribution panel [3], a D.C. to A.C. invcrtcr [4]. a battcry plant 151,
a battc.-ry charger 161, a control unit
17J, a switch unit (8], and an auxiliary distribution panel ]9]. lJnder normal
operating conditions the switch unit
[$] cunnect.c the utility grid [ 1] to the main diAribution panel (3], and tho
switah unit (2] t:cmr,ect,y thc utiGty grid
E] J to the auxiliary distribution panci J91. During this tin)e, and in this
mode, the control unit 171 may activate
the battcry charger 161 and cause the battery plant [5] to be replcnished. At
such time tts the cont.rol unit 17]
recognizes a schcdulcd cvcnt, a manually inducc:d eveirt, or an external cvent
(eg. lJtility grid iailurc), thc contrul
unit (7] may causc: the switch unit [8] to disconnect the utility grid ] 1 I
from thc main distribution panel [3], and
may cause switch unit 121 to d'sticonncx.t the ai.ility grid [ I] frorn the
auxiliary distribution pancl ]91, and may
causc the battcry charger [6] to deactivatc if it is activated, and may cause
switch unit ] 2] to connect thc D.C. to
A.C_ inverter 141 to the auxiliary distribution panel (9]. In this mode the
battcry plant (5] discharl;cx through the
D.C. to A.C. invcrt.er [4] and supplies the energ,y needs ofthc auxiliary
distribution panel [9] tbr an interval of
t.imc. At sueh time as the controllcr rtx.nl;ni=r,~.-s another scheduled
event, a inanually induccd cvcnt, a xystem
cvcnt (eg. depleted battery) or an cxk,rnal evcnt (eg. ulility grid recovcrcd
from fiarlure), the control unit [7] may
cause switch unit 121 to disconncet the D.C. tt) A.C, inverter [4] from the
auxiliary distribution pancl [3] and to
connect the utility girid [I ] to the auxiliary distribution panel (31, irnd
may caus-c: swltch nnrt [8] tl) connect utility
grid [1] to main distribution pancl [3].
Also referring to Fil;urc 2, thcre is an cmergency gcncr=aWr cunneet point ]
12] which allows ior an external
emergenoy generator to be conncctcd to Irattery charger 16] so that the
baltcry plant [5] may be replettished
durinR extended periods of unavailability of tatiiity griti 111. lt should be
nutW that the inclusion ofcmergcncy
gcncrator cl)nncct point [ 121 is not limitcd t)nly to this particular
embodimcnt of 1.hc invcntion.
Referring to Figure 3, another cmlxxiimeat of the invention includcx a utility
grid ] 11, a switch unit 121, a
main distribution partcl 13], a D.C. to A.C. inverter [4], a fuel cell p[ant [
10], a fticl cell fucl storage iacility [ I I],
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CA 02469768 2008-02-18
a control unit 171, a switch unit [R], and axt auxiliary distribution pancl
191. lJndcr normal operating conditions
thc switch unit 181 connccts the utility grid ] l] to tlu; main distribution
panel 131, and thc switch unit 121 connects
the utility grid ] I] to the auxiliary distribution pancl f 9J. At such time
ati thc wnt.rol unit 17] recognire, a
sehcdulcd cvcnt, a manually induced cvcnt, or an cxtcrnal cvent (eg. utility
grid 1'ailurc), thc control unit [7] may
cause the switch unit ]R] to di :connc.c.t thc utility grid I I] from the main
distribution pancl 13], and ntay u3uu
switch unit 12J to disconnect the utility grid ] l] from the auxiliary
distribution panel ]9], :ind may cause switch
unit (2] to conncct the D.C. to A.C. inver(cr [4J to the ctuxili:uy
distribution partcl 19). In this mode the fucl c,c:.ll
plant ] lOj discharges thrtxil;ti thc D.C. to A.C. invartcr [4J and supplies
the cnerl;y rnx;ds of the auxiliary
distribution pancl 191 for an interval o1'time. At such lime as the controller
rccognizcs anothcr scheduled event,
a manually induced cvcnt; a tiystcin cvcnt (cg, dcplcttxi fuel cell) or an
external event (eg_ utiiity grid roc(ivered
from failurc), thc control unit 17) may cause switch unit [2] to disconnect
thc I).("., to A.C. invcrtcr 141 from the
auxiliary cl istributii>n p:utcl [:i] and to amncct the utility grid (1) to
the auxiliary distribution pancl 13], and niay
cause switch unit ]8] to connect utility grid ] I] to main distribution panel
(3], Conirvl unit f 71 n,ay also cause
ftiol cell fucl [11] U) replenish fuci ccll plant I 101 as required and whcn
conditions pcnmit.
Referring to Figure 4, another embodiment of the invention is as described in
Figure 2, only with a csyr.icit.c,)r
plant ] I 5] serving as a storage facility in place of a battery plant (S] and
a capacitor plant ehar};cr 1161 in placc of
battery plant charger 16.1.
Figurc 5 depicts onc cnibodimcnt for a coiitroi proccss that manages the
systein through control unit [7].
Description of St,atcs in Fil=urc 5 (in refcrcncc to the enibodimcnt in Ni ~u~
rc 2)
Events referenced in this section are as described undcr Control lJnit [7]
abovc.
Normal:
In this +tatc: thc yyyt4m is configured to draw resourccs frnm the utiiity
grid [1]. Control unit ],7] caux:s
emcrgency generator connect point 1121 ta bc isolalcxi i'rom battcry charger
161. A IiA'I'-I)l~;I' or a MAN-Rl P
or a'IYII.)-lif;1' cvcnt will c;tuyc: Cttntrol unit [7] to transition f'rom
Nortnal State to Charging St-atc. A 1'Qr)-
OFFCRD or a MAN-OFF(iRD event will cause control unit f 7] to transition from
Normal Statc to Scheduled
01f'Cirid Statc. A Cilill~l~AII. cvcnt will c:aut+t: contrul unit 17] to
trantiitipn from Normal State to
FrnCrgcncy Off Grid State.
Charging:
In thiy rtato thc system rcmains configured to draw resourccs from thc utility
grid I 11, Control unit [7]
causes battcry chargcr 161 to be activated thereby replenislting battery plant
(5]. A BAT-FUL or a MAN-
NI1;PP or a TOI)-NRI:P event will cause control unit ]7) to transition from
Charging State to Normal State.
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A'1'OL)-0FF(iRU or a MAN-OFF(',Rn evcnt will causc control unit [7] to
transiti(,n frum (:harbing State to
Sc;he.dulcd Utf Grid Statc. A systeni warning mestial;c is sent to the user
interface unit [ 13 (:uid machine
interface unit [ 141 in this situation to india:ate that battcry plant (5] was
not fully charged whcn control unit
[7] transilioncd to Schedulcd Off Grid State. A GRID-FA(I, cvont will cause
control unit [_71 to trartsitinn
f'rom ('harging State tt) I:nterl;ency t31C6rid Suttc.
Scheduled O1T4irid:
[n this state control unit [7] causcs swic.ch unit [.ti] tu disconncct utility
grid [1 ] tront main distribution
panel [3] and cauwes switc,h unit [2] to diu:onncct auxiliary distribution
panel [9] from utility T;ric! ] 1] and
causes switch unit M to connect D.C. to A.C. inveitir [4] to auxiliary
tiistributi.on panel [9]. A T3AT-DI:P or
a MAN-NC)FF(.RT) or a TQF's-NQFFCiRT y cvcnt will causc control unit (7) to
transition fmm Scheduled Off
Grid State to Nornial State. A BAT-LOW event will cause control urrit [7] tu
st:nd a systcm wafntinb message
to the user intcrfie" unit [ 13] antl t.c? thc rn;rclrine int.c:rf;tcc unil. [
14~.
Emergency (NF Gr.id:
ln this state the control unit [7] has recognized that the utility grid has
failed_ l1'hattery charging is
;ictiv,ilS:d, control unit [7] cauuss battery a.,HrgGr [6] to t14ac1;vat,c.
Control unit 171 thcn causcs switch unit (8J
to disconttect utility grid I I] trom niain distribution panel [3] attd causes
switch unit 121 tt- elisccynncc;t
auxiliary distribution pancl [9] trnm utilit.y grid [ 1] and cau-,c.%vwitch
unit (2] to conncct D.C. to A.C.
inverter [4] to auxiliary distribution panel [9]. A L3A'L'-UL=',P event will
cause control unit [7] tt- trantiition
from hmcrgs,-ncy O1f (irid State to litnerl;c~ncy Shut T)uwrl State. A GRCL)-
RI:C evenl. will cause controt unit
[7( to transition from Emergency Of C Grid State to Normal State. (An
aiternative implenientation could causc
control unit (7) to transition from I:mergeticy Off C;rid State to Charging
State when a C;RiI)-Rf:Cevent
oceurs)_ A I3AT-LUW event will cause cimtrol unil [7] to send a system warning
niessagc to uscr interface
unit 113J and machinc intcrracc unit 1141,
Fmcrgcncy Shut 1>own;
In this state the battery plant [5] has been depleted and the utility grid has
not yet ra:ovcred or a critical
system failurc has occurrc:d. C:ontrol unit [7] issues an appropriate alert to
user intertace unit [l3] and
n=tachirte intertace unit [14J and causes switch unit 18J to wnnect ntain
distribution panci (3] lo utility grid (1 ],
and causes switch unit [2] to 4onnect auxiiiary distribution panel [9] to
utility grid [ I J. lf'battery charging is
activated, control unit [7] causes battery cltarbcr [6] to d+;activatc. A
TiA'f-RE(: cvcnt will c:ruse controi unit
171 to transition 1'rom I:mergency Shut Down State ::o k?mergency Off (irid
State. (Such an event might occur
if an external generator were to be uscd to rcplcnish battery unit [S']). A
GRID-REC tir a MAN-CLEAR
cvcnt will cattxe control unit ]7] to transition from l;mcrgcncy Shut l)own
tit.ttc tu Normal St;,tc.
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CA 02469768 2008-02-18
All stateti:
During any state control unit 17) may monitor for system status ix
inconsistencies :tnd cause an alert tn occur
should an appropriatc condition arise (eK_ hal I.c.-ry char,ying aetivntcd
whcn systern rtt.cmpts a transition from
Narmal statc to Scheduled Off (;rid state, or batt~.=ry low, or bat:tery
deplctcd, ctc).
During arry cridc:il systcni failure that tnav bc dctected in any statc the
system will transition to I?tttcrl;cncy
Shul 1)own statc_
~ 0 ConclugioA
A nictlxxi fix autumatically storing electrical v-ncrgy from a utility grid is
proposed which allows customers
of said utility to storc up clcctrical cnc=rff at r.chcduled times when cost
to consutne utility rc,~ourccs ntay hc
rclatively low_ C.ustomcrti may than discannc=ct fmin said ut.ility and
cunsumc slored enerbo,}+ at xc:hcdulcd times
when eost tn consumc utility resources may bc rclatively high. 7'hc systcm
described hercin also providc.~s fe>r
emerp,ency power itt thc cvcnt ofa utility failure_
P.xistinl; mcthods provide for muitiplc altcrnatc power sources rnd storage
tnedia tcs Ix: used as back-up
power in the event, of utility grid failure, or to ntinimiz;c dcpendoncy on
utility grid power. Where ccxet
avoidance cr utility grid peak dentand relicf is the objective, existing
methods propeAe clalxtrntc mcthodologie:+
li-r dcterntining peak consumption profile or tor comrnuni,:ating with the
utility U- determine current cost of
utility resource consumption. The methodology dcscribed herein governs itsclf
according tu pn:dc.-icrmined
scheduled events driven by built in time ot'day attd calendar functions.
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