1 Da Volt Var Control Optimization

Volt VARControl&Optimization

BobUluskiQuantaTechnology

2010 Quanta Technology LLC

WhatisVoltVARcontrol? VoltVARcontrol(VVC)isafundamentaloperatingrequirementofall

electricdistributionsystems

TheprimepurposeofVVCistomaintainacceptablevoltageatallpointsalongthedistributionfeederunderallloadingconditions

LTC

Primary Feeder

SUBSTATION

Primary Feeder

Secondary

Distribution Transformer

Service Drop WiresFirst

Customer

Last Customer

Customer

Voltage

3 volts Primary

2 volts distribution transformer

1 volt secondary

1 volt service drop

122

119117116

First Customer


Distance

115 Last CustomerANSI C84.1 Lower Limit (114 volts)114

WhatisVoltVARcontrol? WithoutVVC:

Voltagemightbeokayduringaverageload

Transformer T P i i

120V

126VTap Position

114V

D

S E F

F C L C


S


voltagemightdroopbelowtheminimumacceptablelevelforsomecustomersduringheavyloadperiods

Transformer T P i i

120V

126VTap Position

114VLow Voltage

D

S E F

F C L C


S


Couldraisethemanualtapsettingonthesubstationtransformertocorrect the peak load problemcorrectthepeakloadproblem

Transformer Tap Position

120V

126V

114V

D

S E F

F C L C


S


Butwhenfeederloadinginlight,highvoltagecouldbeaproblem at the substation end of the feederproblematthesubstationendofthefeeder

Transformer Tap Position High Voltage

120V

126V

114V

D

S E F

F C L C


S


Butwhenfeederloadinginlight,highvoltagecouldbe a problem at the substation end of the feeder

N VVAR

C S

beaproblematthesubstationendofthefeeder

Transformer Tap Position

120V

126V

114V

D

S E F

F C L C


S

VVC=VoltageRegulation+ReactivePowerCompensation

Use voltage regulators (Vregs) or transformers with load tap changers Usevoltageregulators(Vregs)ortransformerswithloadtapchangers(LTCs) thatautomatically raiseorlowerthevoltageinresponsetochangesinload

Use capacitor banks to supply some of the reactive power that would Usecapacitorbanks tosupplysomeofthereactivepowerthatwouldotherwisebedrawnfromthesupplysubstations


D

SS

E F

VVCinTodaysOperatingEnvironment(andTomorrowsOperatingEnvironmentToo!)

Maintainingthestatusquo nolongeracceptable UtilitiesareseekingtodomorewithVVCthanjustkeeping

voltagewithintheallowablelimits

S t ti i ti i i t t t f th l Systemoptimization isanimportantpartofthenormaloperatingstrategyundersmartgrid

AspenetrationofintermittentrenewablegeneratingAs penetration of intermittent renewable generatingresourcesgrowsinfuture,highspeeddynamicvoltVARcontrolwillplayasignificantroleinmaintainingpowerquality and voltage stability on the distribution feedersqualityandvoltagestabilityonthedistributionfeeders


VoltVARControlinaSmartGridWorld

ExpandedobjectivesforVoltVARcontrolinclude Basic requirement maintain acceptable voltageBasicrequirement maintainacceptablevoltage SupportmajorSmartGridobjectives:

Accomplishenergyconservationff ( d h l l ) Improveefficiency(reducetechnicallosses)

Promoteaselfhealinggrid(VVCplaysaroleinmaintainingvoltageafterselfhealinghasoccurred)

Enable idespread deplo ment of Distrib ted generation Rene ables EnablewidespreaddeploymentofDistributedgeneration,Renewables,Energystorage,andotherdistributedenergyresources


RequirementsfortheIdealVoltVARSystem

MaintainAcceptableVoltageProfile atallpointsalongthedistributionfeederunderallloadingconditions

MaintainAcceptablePowerFactor underallloadingconditions ProvideSelfMonitoring alertdispatcherwhenavoltVARdevice

f ilfails

AllowOperatorOverride duringsystememergencies Work correctly following Feeder ReconfigurationWorkcorrectlyfollowingFeederReconfiguration AccommodateDistributedEnergyResources ProvideOptimalCoordinatedControl ofallVoltVARdevices AllowSelectableOperatingObjectives asdifferentneedsarise


Approaches to Volt VAR ControlApproachestoVoltVARControl

Traditional ApproachTraditionalApproach

DLA Master Station

Switched Capacitor Bank

SCADA Volt VARDistribution

SCADA

Distribution Power Flow

p

SCADAVoltVAR

Integrated Volt VAR

IVVCApplication

Substation RTU

Line Regulator

IntegratedVoltVARSubstationCapacitor Bank

Substation TransformerWith Load

Tap Changer


TraditionalVoltVARControl

Current/VoltageSensor

CapacitorBank

Distribution Primary LineCurrent/Voltage

Sensor

Voltage R l tBank

"Local" Current/Voltage

Measurements On/Off Control Command

Regulator



Standalone Controller

CommandSignal Standalone

Controller

CommandSignal

VoltVARflowsmanagedbyindividual,independent,standalonevoltVARregulatingdevices:

Substation transformer load tap changers (LTCs) Substationtransformerloadtapchangers(LTCs) Linevoltageregulators Fixedandswitchedcapacitorbanks


Limitations of Traditional ApproachLimitationsofTraditionalApproach

Power factor correction/loss reductionPowerfactorcorrection/lossreduction Manytraditionalcapbankcontrollershavevoltagecontrol (switch on when voltage is low)control(switchonwhenvoltageislow)

Reactivepowercontrollersavailable,butexpensive(needtoaddCT) Goodatmaintainingacceptablevoltage Good at PF correction during peak load seasons may not come on at all GoodatPFcorrectionduringpeakloadseasonsmaynotcomeonatallduringoffpeakseasons

ResultisthatPFisusuallygreat(nearunity)duringpeakloadperiodsandlowduringoffpeakseasons(higherelectricallosses)g p ( g )


MonitoringofSwitchedCapacitorBankfPerformance

Switched capacitor banks are notorious forSwitchedcapacitorbanksarenotoriousforbeingoutofserviceduetoblownfuses,etc.

With traditional scheme switched capacitor Withtraditionalscheme,switchedcapacitorbankcouldbeoutofserviceforextendedperiods without operator knowingperiodswithoutoperatorknowing LosseshigherifcapbankisoutofserviceR i i i d d? Routineinspectionsneeded?


TraditionalVoltageRegulationStrategy

LineDropCompensationaccountsforvaryingload

Wh l d th h ltLTC

Whenloadthroughvoltageregulatorishigh,voltagedropalongthefeederwillbehigh

LTC i lt t

SUBSTATION

Primary Feeder

Secondary

Distribution Transformer

Service Drop WiresFirst

LTCraisesvoltagetocompensate

Thisapproachworkswellwhenll f d l d th h th

Last Customer

Customer

Voltage

allfeederloadpassesthroughthevoltageregulator

3 volts Primary

2 volts distribution transformer

1 volt secondary

1 volt service drop

122

119117116115

First Customer

Last Customer

Distance

Last CustomerANSI C84.1 Lower Limit (114 volts)114


VoltageRegulationProblemWhenLargeDGUnitisIntroduced

WithalargeDRoutonthe feeder load throughthefeeder,loadthroughVregwillbereduced

Vreqthinksloadislightonthefeeder

Vreglowerstapsettingtoavoidlightload,highvoltagecondition

This action makes theThisactionmakestheactualheavyload,lowvoltageconditionevenworse

DMS that accounts for DMSthataccountsforDGaffectscanmaketheproperraise/lowerdecisionbasedontotalfeeder conditions


feederconditions

VoltageRegulationDuringAlternateFeedConfiguration

Olderstylevoltageregulatorswereoftendesignedtohandleapurelyradialsituation powerflowalwaysfromthesamedirection(fromthesubstation)

OlderstyleVregsmaynotworkcorrectlyifpowerflowisfromtheoppositedirection(seeexample)

Couldraisevoltagewhenduringlightload,creatinghighvoltagesituation Couldlowervoltagewhenduringheavyload,creatinglowvoltagesituation

Feederreconfigurationmaybecomeamorefrequentoccurrencedueto Loadtransferredtoanotherfeederduringservicerestoration(FLISR)g ( ) Optimalnetworkreconfigurationtoreducelosses(DMSapplication)

Vreg not bi-directional


Incorrect Operation!

UseofBidirectionalVoltageRegulator

CanUseBidirectionalvoltageregulatorcontrollertohandlefeederreconfiguration

Thesemaketheoppositetappositionmovementwhenflowisfromthereversedirectiondirection

Vreg bi-directional


Correct Operation!

Reverse Power Flow with DGReversePowerFlowwithDG ADGofsufficientsizecanreverse

powerflow BidirectionalVoltageRegulator

Vreg bi-directional

g gmaynotworkcorrectly

DGdoesnottypicallyprovideasourcestrengthstrongerthanthesubstation

Direction of Power Flow

1.0 1.0

Normal Load

DG

substation. Substationsidevoltagedoesnot

change, DGsidechangesE ith Bidi ti l V

Direction of Power Flow

Normal Load

VsVl

Vl = Vs

EvenwithBidirectionalVreg,couldwinduploweringthevoltageonaportionorthefeederduringheavyload

diti

.901.0Increased

Load

Vs VlVl = Vs x .90

DG

conditions Conclusion: Needamore

sophisticatedvoltagecontrolstrategywhenDGpenetrationis

Vl

Incorrect Operation!


largeenoughtoreversepowerflow

LimitationsofTraditionalVoltVARControl

Current/VoltageSensor

CapacitorBank

Distribution Primary LineCurrent/Voltage

Sensor

Voltage R l tBank



Regulator



Standalone Controller

CommandSignal Standalone

Controller

CommandSignal

Thesystemisnotcontinuouslymonitored Thesystemlacksflexibilitytorespondtochangingconditionsoutonthe

distribution feeders can misoperate following automatic reconfigurationdistributionfeeders canmisoperatefollowingautomaticreconfiguration Systemoperationmaynotbeoptimalunderallconditions Cannotoverridetraditionaloperationduringpowersystememergencies


Systemmaymisoperatewhenmoderngriddevices(e.g.,distributedgenerators)arepresent reversepowerflowfromDGcantrickstandalonecontrollertobelievefeederhasbeenreconfigured

ScorecardforTraditionalVoltVAR

V lt VAR R i t Traditional Volt-Volt VAR Requirements Traditional VoltVARAcceptable Voltage Profile XAcceptable Power Factor XSelf MonitoringOperator OverridepFeeder Reconfiguration SmartGrid DevicesOptimal Coordinated ControlOptimal Coordinated ControlSelectable Operating Objectives


SCADA Controlled VoltVARSCADA ControlledVolt VAR

VoltVARpowerapparatusmonitoredandcontrolledbyp pp ySupervisoryControlandDataAcquisition(SCADA)

VoltVARControltypicallyhandledbytwoseparate(i d d t) t(independent)systems: VARDispatch controlscapacitorbankstoimprovepowerfactor,

reduceelectricallosses,etc

VoltageControl controlsLTCsand/orvoltageregulatorstoreducedemandand/orenergyconsumption(aka,ConservationVoltageReduction)

Operationofthesesystemsisprimarilybasedonastoredsetofpredeterminedrules (e.g.,ifpowerfactorislessthan0 95 then switch capacitor bank #1 off)


0.95,thenswitchcapacitorbank#1off )

Overall Objective of VAR dispatchOverallObjectiveofVARdispatch

M


VARDispatchComponents

Switched&fixedfeedercapacitorbanks Capacitorbankcontrolinterfacep Communicationsfacility onewaypagingorload

managementcommunicationsissufficient

Meansofmonitoring3phasevarflowatthesubstation


substation

MasterstationrunningVARdispatchsoftware

MonitoringRealandReactivePowerFlow


VARDispatchRulesApplied


RealandReactiveLoadIncreases


ReactivePowerFlowExceedsThreshold


CapacitorSwitchedOn


ChangeinReactivePowerDetected


ChangeinReactivePowerDetected

Change detected by Substation

RTU


RTU

BenefitsofVARDispatchvsTraditional

SelfMonitoring Operatoroverridecapability


Someimprovementinefficiency

ObjectivesforSCADAVoltageControl

Maintain acceptable voltage at all locationsMaintainacceptablevoltageatalllocationsunderallloadingconditions

Operate at as low as voltage as possible to Operateataslowasvoltageaspossibletoreducepowerconsumption(akaConservationVoltage Reduction)VoltageReduction)


ConservationVoltageReduction


Source: Tom Wilson PCS Utilidata

BenefitsofVoltageReductionforVariousTypesofLoads

Constantimpedance (powerconsumedisproportionaltovoltagesquared) Incandescentlighting,resistivewaterheaters,stovetopandovercookingloads

Constantpower (demandisconstantregardlessofvoltage) Electricmotors,regulatedpowersupplies

Constantcurrent(demandisproportionaltovoltage)(fewofthistypeofload) Weldingunits,smelting,electroplatingprocesses

Feederloadisalwaysamixofthedifferentloadtypes

Rules of thumb: Rulesofthumb: 60/40split(constantpower/constant

impedance)forsummerpeakloads

40/60splitforwinterpeakloads 80/20forindustrialareas 70/30forresidentialloadinresidentialwith

summerpeaking

30/70forresloadwithwinterpeaking Commercialloads:50/50or60/40

Source: Power Distribution Planning


Source:PowerDistributionPlanningReferenceBook,H.LeeWillis

BenefitsofVoltageReduction

Worksbestwithresistiveload (lightingandresistiveheating)becausepowerdrawndecreaseswiththevoltagesquared.

P = V 2 RConstant

Impedance load

Devicesthatoperateusingathermostatgenerallydonotreduceenergy thedevices


justrunlonger

BenefitsofVoltageReduction

Efficiency improve for small voltage reduction

Incremental change in efficiency drops off and then turns negative as voltage is reduced

Negative effect occurs sooner for heavily loaded motors


BenefitsofVoltageReductiononmotors Motorlossreductionisabalancingactbetweenmagnetic

effectsandelectricaleffects: Magneticlosses(IronLosses)arereducedwhenvoltageislowered Motorcurrentincreasesasvoltageisdecreased(constantpowereffect) but

ifmotorloadingislight,currentincreasesgradually

Initialeffectisreducedenergyassumption,butasvoltageisdeceasedfurther,copperlossincreasesandmotorbecomeslessefficient

Power Savings Obtained from Supply VoltageVariation on Squirrel Cage Induction Motors

C. D. Pitis, BC Hydro Power Smart, and M. W. Zeller, BC Hydro Power Smart


BC Hydro Power Smart

EmergingLoadCharacteristics DigitalDevices:

Typicallyhaveauniversalpowersupplycoveringawiderangeofinputvoltagevariations(e.g.:LCD/PlasmaTV&VCRs=80240V)g ( g )

Constantpowerbehavior

ElectricVehicleChargers:C Constantpower

ConstantVoltage(regulatedoutput,duringmaintenancecharge) Constantcurrent(Lowstateofchargeandfastchargingtype)

NiMH Charging Profile


Example charging curves for two EV chargers

Voltage Control ComponentsVoltageControlComponents

EOF V ltEOF Voltage measurement126V

Actual

114V

116VCVR

Cutoff

Voltage

EOF = End of feeder


EOFVoltageBelowVoltageControlThreshold(No Control Actions)(NoControlActions)

EOF V ltVoltage Control

ProcessorComm

Interface

EOF Voltage measurement126V

Actual

LTCSubstation

RTUVolt Meter

or AMRComm Interface

LTCController

Substation Transformer

114V

116VCVR

Cutoff

Voltage

OO

Reactive Power (MVAR)

Real Power (MW) End ofFeeder

OOOOOO

OO Voltage Transformer

Reactive Power (MVAR)EOF = End of feeder


EOFVoltageAboveVoltageControlh h ldThreshold

EOF V ltVoltage Control

ProcessorComm

Interface


Actual Voltage

LTCSubstation

RTUVolt Meter


LTCController


114V

116VCVR

Cutoff

OOEnd ofFeeder

OOOOOO

OO

EOF = End of feeder


EOFVoltageAboveVoltageControlThreshold(lower tap setting)(lowertapsetting)

EOF V lt

Voltage Control Processor

Comm Interface

Lower Tap


Actual Voltage

LTCSubstation

RTUVolt Meter


LTCController


Setting

114V

116VCVR

Cutoff

OOEnd ofFeeder

OOOOOO

OOTransformer

EOF = End of feeder


EOFVoltageAboveVoltageControlThreshold(lower tap setting)(lowertapsetting)

EOF V lt

Voltage Control Processor

Comm Interface

Lower Tap


Actual Voltage

LTCSubstation

RTUVolt Meter


LTCController


Setting

114V

116VCVR

Cutoff

OOEnd ofFeeder

OOOOOO

OOTransformer

SelfMonitoring Operatoroverridecapability


CVRfunctionnotavailablewithtraditional

CVRbasedonVoltagemeasurementsCVRbasedonVoltagemeasurements

HydroQuebecResults: Simplebutnotfullyeffective.Demonstrationprojectgained

only 30% of the estimated energy consumption.only30%oftheestimatedenergyconsumption. Voltmetersnotreallyattheendofthefeeders.Voltmetersinstalledonlyon3phasescircuits.Targetsneedtocoveralsotheworstcasevoltagedropofthesinglephasenetworks.

Networktopologyduringthedemonstrationproject(1yearaverage)wasnotinitsnormalstate40%ofthetime.

Volt Meter

Communication network

Substation

End of Feeder

Regulationllcontroller

A local regulation controller monitors the end of feeders voltage and


Source: Volt-VAR Control Implementation at Hydro Qubec; Presented by Herve Delmas to IEEE Smart Distribution Volt Var

Task Force, January 2010

A local regulation controller monitors the end of feeder s voltage and sets the tap to maintain this voltage at 115V.

LackofCoordinationbetweenVoltandlVARcontrol

Switching a capacitor bank on raises theSwitchingacapacitorbankonraisesthevoltage,which: Increases no load losses in distribution Increasesnoloadlossesindistributiontransformers

Increases energy consumption and possiblyIncreasesenergyconsumptionandpossiblydemand

Lowering the voltage through CVR:LoweringthevoltagethroughCVR: Makesthecapacitorbankslesseffective(lowervoltage means less capacitive current delivered by


voltagemeanslesscapacitivecurrentdeliveredbythecapbanks)

SCADAVoltVARSummaryy Doesnot adapttochangingfeederconfiguration (rules are fixed in advance)configuration (rulesarefixedinadvance)

Doesnot adapttovaryingoperatingneeds(rules are fixed in advance)(rulesarefixedinadvance)

Overallefficiencyisimprovedversustraditional approach but is not necessarilytraditionalapproach,butisnotnecessarilyoptimalunderallconditions

Operation of VAR and Volt devices is not OperationofVARandVoltdevicesisnotcoordinated

Does not adapt well to presence of modern


Doesnot adaptwelltopresenceofmoderngriddevices suchasDG

SampleCalc:kWhLossSavingsDuetoVAR DispatchVARDispatch

Sample Calculation 2: Savings Due to kWh Reduction Input Values: Target power factor (TPF) = 1 00 usefulTarget power factor (TPF) = 1.00 Average power factor (AVGPF) = .95 Peak load on feeder (PKLOAD) = 8,000 kilowatts Distribution losses (% of peak load) = 4.0% Average cost to purchase one kilowatt-hour = 0.04 $/kWh

useful formula

g p $ Annual savings per feeder = 8760 x .456 x DLOSS x PKLOAD x (1 AVGPF2 / TPF2) x .04 kWh per year = 8760 x 0.456 x 4% x 8000 x (1 - .952 / 1.02) * .04

$ f = $4,985 per year per feeder


SampleCalculation:DemandReductionDue to VAR DispatchDuetoVARDispatch

Sample Calculation 3: Savings in Energy Supplier Demand ChargesSample Calculation 3: Savings in Energy Supplier Demand Charges Input Values: Target power factor (TPF) = 1.00g p ( )Power factor at peak load (PKPF) = .98 Peak load on feeder (PKLOAD) = 8,000 kilowatts Energy supplier demand charge (DEMCHG) = 20 $/kW

useful formula

Annual savings per feeder = (1/PKPF - 1/TPF) x 100 % x PKLOAD x DMDCHG = (1 / 0.98 1 / 1.00) x 100% x 8,000 x 20

$3 265 f d = $3,265 per year per feeder


Volt VAR ScorecardVoltVAR Scorecard

Volt-VAR Approach

Volt VAR Requirements Traditional Volt-VARSCADA Volt-

VAR

A t bl V lt P fil X X

pp

Acceptable Voltage Profile X XAcceptable Power Factor X XSelf Monitoring XOperator Override XOperator Override XFeeder Reconfiguration SmartGrid DevicesOptimal Coordinated ControlSelectable Operating Objectives


VoltVAROptimization(CentralizedApproach)

Developsandexecutesacoordinatedoptimalswitchingplanforall voltagecontroldevices

Uses optimal power flow program to decide what to Usesoptimalpowerflowprogramtodecidewhattodo

Achieves utilityspecified objective functions:Achievesutility specifiedobjectivefunctions: Minimize distribution system power loss Minimize power demand (sum of distribution power loss and

customer demand)customer demand) Maximize revenue (the difference between energy sales and energy

prime cost) Combination of the above

Can bias the results to minimize tap changermovement and other equipment control actions that

ddi i l d h h i l


put additional wear and tear on the physicalequipment

ModelingLoadVoltageSensitivity

AccurateloadmodelforIVVC:

Determineappropriatevaluesforcoefficientsonabove formula using field experiments andaboveformulausingfieldexperimentsandregressionanalysis


VoltVAROptimization(VVO)Systemfi iConfiguration

Temp Changes

MDMSAMI Line Switch

Distribution System Model

Geographic Information

System (GIS)

Perm Changes

Dynamic Changes

Switched Cap

Bank

Distribution SCADA

On-Line Power Flow (OLPF)

IVVC Optimizing

Engine

Line Voltage

RegulatorDevelops a coordinated

optimalSubstation RTU

Substation Transformer with TCUL

Substation Capacitor

B k

optimal switching plan for all voltage control

devices and executes the plan


with TCUL Bankexecutes the plan

VoltVAROptimization(VVO)SystemOperation

Voltage Feedback

Temp Changes

MDMSAMI Line Switch

Switch Status

Voltage Feedback, Accurate load data

Bank voltage & status, switch control



System (GIS)

Perm Changes

Dynamic Changes Switched

Cap Bank

switch control

Distribution SCADA

On-Line Power Flow (OLPF)IVVC requires real-

time monitoring & control of sub &

IVVC Optimizing

Engine

Line Voltage Regulator

Monitor & control tap

control of sub & feeder devices

Substation RTU



Bank Bank voltage & status

pposition, measure load

voltage and loadMonitor & control tap position, measure load

voltage and load


Bank voltage & status, switch control

VoltVAROptimization(VVO)SystemOperation

Temp Changes

MDMSAMI Line Switch

Cuts, jumpers, manual switching

Real-Time Updates



System (GIS)

Perm Changes


Cap Bank

Distribution SCADA

On-Line Power Flow (OLPF)Permanent asset changes

(line extension, d t )

IVVC Optimizing

Engine


reconductor)

Substation RTU



Bank

IVVC requires an accurate, up-to date

electrical model


Bank

VoltVAROptimization(VVO)SystemOperationOperation

Temp Changes

MDMSAMI Line Switch



System (GIS)

Perm Changes


Cap Bank

Distribution SCADA


OLPF calculates losses, voltage

profile, etc

IVVC Optimizing

Engine


PowerflowSubstation RTU



Bank

Powerflow Results


Bank


Temp Changes

MDMSAMI Line Switch



System (GIS)

Perm Changes


Cap Bank

Distribution SCADA


Determines optimal set of control

actions to achieve a desired objective

IVVC Optimizing

Engine


Powerflow

j

Substation RTU



Bank

Powerflow Results

Alternative Switching


BankSwitching Plan


Temp Changes

MDMSAMI Line Switch



System (GIS)

Perm Changes


Cap Bank

Distribution SCADA


Determines optimal set of control

actions to achieve a desired objective

IVVC Optimizing

Engine


j

Substation RTU



Bank

Optimal Switching


BankSwitching Plan

ImpactofVoltageReductiononCustomers

In most cases, voltage reduction does not impactInmostcases,voltagereductiondoesnotimpactcustomerequipment,but..

Somecustomersareawareoftheprincipleofvoltagep p greductionandgavealreadytakenstepstolowertheirvoltageviaindividualservicevoltageregulators(e.g.Smartmotorcontrollers)

Whenutilitylowersthevoltageonthefeeder,h l d l hcustomerswhoarealreadyloweringtheirown

voltagewillgobelowtheminimum


Voltage Reduction LimitationsVoltageReductionLimitations Feedersvoltagelimited?

Maynotbeabletoreducevoltageatall Mayneedtoflattenthevoltageprofile(Progressenergy,GeorgiaPower,etc)


CurrentTechnologies,LLC


TimeDecayofCVREffects Themostreductionoccursrightwhenthevoltageisreducedandthensomeofthereductionislostassome loads j st r n longersomeloadsjustrunlonger


IVVCBenefitsD i d l d t t ti ll h Dynamicmodelupdatesautomaticallywhenreconfigurationoccurs

Volt VARcontrolactionsarecoordinated

SystemcanmodeltheeffectsofDistributedGenerationandothermoderngridelements

Producesoptimalresults

Accommodatesvaryingoperatingobjectivesd di t d


dependingonpresentneed

Benefits of Volt VAR OptimizationBenefitsofVoltVAROptimization CVRFactor=P/VbasiconactualCVRexperience:

BC H d CVR 0 7 BCHydroCVRf = 0.7 ProgressEnergyCVRf =0.8 Georgia Power CVRf = 0 8GeorgiaPowerCVRf = 0.8

AnnualEnergySavings =AverageLoadx#Hoursperyearx%voltagereductionxCVRfxvalueofenergyconservationLostrevenuefromkWhsales

CVRperformedduringpeakloadperiodcanbeviewedasdemand (capacity) reductiondemand(capacity)reduction


Final VoltVAR ScorecardFinalVolt VAR Scorecard

Volt VAR Approach

Volt VAR Requirements Traditional Volt-VARSCADA Volt-

VARIntegrated Volt-

VAR

A t bl V lt P fil X X X

Volt-VAR Approach

Acceptable Voltage Profile X X XAcceptable Power Factor X X XSelf Monitoring X XOperator Override X XF d R fi tiFeeder Reconfiguration XSmartGrid Devices XOptimal Coordinated Control XSelectable Operating Objectives X


VoltVAROptimization NextSteps

SUBSTATION

PV Inverter PV

Inverter

SUBSTATION

PV Inverter PV

Inverter

SUBSTATION

FEEDER

Supplementary Regulators


Rotating DG

SUBSTATION

FEEDER



Rotating DG

Rotating DG

Rotating

Capacitor ControlLTC Control

PF Rotating

Rotating DG

PV Inverter PV

Inverter

RotatingRotating

Capacitor ControlLTC Control

PF RotatingRotating

Rotating DG

Rotating DG

PV Inverter PV

Inverter

Rotating DG Capacit

or

Rotating DG

Rotating DG

Rotating DG Capacit

or

Rotating DG

Rotating DG

Voltage and VAR Regulation

Coordination Al ith

Manages tap changer settings, inverter and rotating machine VAR levels, and capacitors to regulate voltage, reduce l d

Communication Link

Voltage and VAR Regulation

Coordination Al ith

Manages tap changer settings, inverter and rotating machine VAR levels, and capacitors to regulate voltage, reduce l d

Communication Link


Algorithm losses, conserve energy, and system resources

Algorithm losses, conserve energy, and system resources

FeederFlowandResourceControl(DG+ES)

ES

DR

Utility grid

DR

PG

DG

RES

ConstantpowerfloworfirmingupPW

rateofchangeatPCC Eliminateadverseimpact

Reduce reserve capacity requirement


Reducereservecapacityrequirement

Documents

1 Da Volt Var Control Optimization