INTEGRATED TRANSMISSION PLAN Glossary - · PDF filethe flow of electric current from line to earthing system to earth ... 2017 Integrated Transmission Plan Glossary 3 ... 2017 ITP

GlossaryINTEGRATED TRANSMISSION PLAN

SEPTEMBER 2017

2017IntegratedTransmissionPlanGlossary 1

GLOSSARY Term Description

AC Alternatingcurrent

ACM Asbestoscontainingmaterials

assethealthandassethealthindex(AHI)

Assethealthisexpressedusinganassethealthindex(AHI)

AHIisamodellingmethodthatestimatestheremainingusefullifeforassets.Ittakesintoaccountarangeoffactorssuchasassetcondition,failurerate,andenvironmentalfactors,dependingontheassetclass

automaticunder-frequencyloadshedding(AUFLS)

Theautomaticdisconnectionofcustomersforsevereorprolongedunderfrequencyexcursion

availability Thenumberofhoursperyearthenetworkorpartofthenetworkisinservice

bus Thecommonprimaryconductorofpowerfromapowersourcetotwoormoreseparatecircuits

cable Oneormoreinsulatedconductorsformingatransmissioncircuitaboveorbelowground

capacitorbankAnumberofcapacitorsconnectedtogetherinaseriesorparalleltoformtherequisitecapacitanceandvoltageratingforreactivecompensationandharmonicfiltersonthepowersystem

capex Capitalexpenditure

CapexIM TranspowerCapitalExpenditureInputMethodologies

circuit

Asetofconductors(usuallythree)plusassociatedhardwareandinsulationonatransmissionline,whichtogetherformasingleelectricalconnectionbetweentwoormorestationsandwhich,whenfaulted,isremovedautomaticallyfromthesystem(bycircuitbreakers)asasingleentity

circuitbreakerAswitchingdevice,capableofmaking,carryingandbreakingcurrentsundernormalcircuitconditionsandalsomaking,carryingforaspecifiedtimeandbreakingcurrentsunderspecifiedabnormalconditions,suchasthoseofshortcircuit

commissioned Theoperationalstateofequipmentthathasundergonethecommissioningprocessandisbroughtundertheoperationalcontrolofaservicecentre/controller

constraint Alocallimitationinthetransmissioncapacityofthegridrequiredtomaintaingridsecurityorpowerquality

contingency

Aneventthatcanoccuronthepowersystem.Forexample,asinglecontingencycouldbe:

• inrelationtotransmission,theunplannedtrippingofasingleitemofequipment

• inrelationtoafallinfrequency,thelossofthelargestsingleblockofgenerationinservice,orthelossofoneHVDCpole.

controlleddocumentAtechnical,safetyorcompliancedocumentregisteredwithintheTranspowersystem.Weissue,amendandwithdrawacontrolleddocumentthroughaformalqualityprocesssystem

coregrid ThemainelementsofthetransmissiongridasdefinedinSchedule12.3oftheElectricityIndustryParticipationCode2010

criticality

Weuseanassetcriticalityframeworktoestimatetheconsequencesoffailureforeachasset.ThisframeworkapproachisnewtoTranspower,andisstillunderdevelopment.Wearedevelopingthisframeworktocoverarangeofdimensionsofconsequence.Itcurrentlyincludesserviceperformanceandpublicsafety

earthpotentialrise(EPR) Thepotential(difference)betweenthelocalearthandtheearthataremotepointduetotheflowofelectriccurrentfromlinetoearthingsystemtoearth

E&D Enhancementanddevelopment

2017IntegratedTransmissionPlanGlossary 2

Term Descriptionelectricitydistributionbusiness(EDB)

Anassetownerwhoseassetsarepredominantlyforthedistributionofelectricitytocustomers

ElectricityIndustryParticipationCode

AstatutoryinstrumentsettingouttherequirementsontheelectricityindustrypursuanttotheElectricityIndustryAct2010

feeder Acircuitthatprovidesadirectconnectiontoacustomer

FMIS Financialmanagementinformationsystem

forcedoutage Theautomaticorurgentremovalfromserviceofanitemofequipment

frequency Therateofcyclicchangeinvalueofcurrentandvoltage,quantifiedbytheinternationalstandardterm‘Hertz’(Hz)

gasinsulatedswitchgear(GIS)

Metal-enclosedswitchgearinwhichtheinsulationandarcextinctionisobtainedbyaninsulatinggas,usuallySF6

GOM GridOperatingModel

grid ThepartoftheNewZealandelectricitytransmissionsystemthatisoperatedbyTranspower

gridexitpoints(GXP) Apointofconnectionwhereelectricitymayflowoutofthegrid

gridinjectionpoints(GIP) Apointofconnectionwhereelectricitymayflowintothegrid

gridmetermanagementsystem(GMMS) Ameteringdatarepositoryanddatamanagementsystem

high-voltage(HV) Unlessotherwisenoted,HVgenerallymeansabove66kV

HVAC Highvoltagealternatingcurrent

HVDC Highvoltagedirectcurrent

hypoxicairfiresuppression

Anactivefireprotectiontechniquebasedonapermanentreductionoftheoxygenconcentrationintheprotectedrooms(alsoknownasoxygenreductionsystem)

ICT InformationandCommunicationsTechnology

intelligentelectronicdevice(IED)

Adevicethatperformselectricalprotectionfunctions,advancedlocalcontrolintelligence,hastheabilitytomonitorprocessesandcancommunicatedirectlytoaSCADAsystem

integratedoutagenotificationsystem(IONS) Asystemwhichhelpsschedule,coordinateandtrackgridoutages

IntegratedWorksPlan(IWP) Ourworksplanwhichincludescapexandopexwork

ISO55000 ApublicallyavailableinternationalstandardforassetmanagementdevelopedandpublishedbytheInternationalOrganisationforStandardisation

livelineworkWorkperformedonornearnormallyenergisedtransmissioncircuitcomponents,withoutusingisolatingandearthingprocedures,andatdistancescloserthantheminimumapproachdistancesspecifiedinSR-EIRule703

Maximo Ourcoreassetmanagementinformationsystemforallgridasseswhichholdsouroperationalassetregisterandisourmaintenancemanagementtool

medium-voltage(MV) Unlessotherwisenoted,medium-voltagegenerallymeansbelow66kV

NGOC OurtwoNationalGridOperatingCentresinAucklandandChristchurch

N,N-1 ReferstotheplanningstandardthatTranspowergenerallyplansthegridto.

TheN-1securitylevelprovidessupplysecuritytotheconnectedloadsunderasinglecrediblecontingencywithalltheassetsthatcanreasonablybeexpectedinservice.AnNsecuritylevelmeansthattheoutageofoneormoreassetswillinterruptload.Itisoftenfoundinsmallersupplyareas,wherejustonetransmissioncircuitorsupplytransformerprovidessupply

networkstudiesSimulationoftheactualpowersystemusingcomputermodels,toanalysetheeffectsofchangestoinputs(likedemand,supply,andassetratings),andidentifyconstraintsorotherissuesthatmightaffectsecurityofsupplytoaregion

opex Operationalexpenditure

2017IntegratedTransmissionPlanGlossary 3

Term Description

outage Thestateofanitemofequipmentwhenitisnotavailabletoperformitsintendedfunction.Anoutagemayormaynotcauseaninterruptionofsupplytocustomers

PAS55

Apubliclyavailablespecification(PAS),publishedbytheBritishStandardsInstitutethatspecifiestherequirementsfororganisationsseekingtodemonstrategoodassetmanagementpractices.ThisspecificationhassubsequentlybeensupersededbytheISO55000assetmanagementstandard

plannedoutage Adeliberateoutagescheduledformaintenancepurposes

point-of-service Anormallycontiguouselectricalbusbarataparticularvoltageatwhichwehaveagreedtoprovideservicestooneormoretransmissioncustomers

powertransformer Atransformerthatprimarilychangesvoltageandcurrentfortheefficientconveyanceofelectricityoverthecircuitsconnectedtoit

primaryassets Powersystemequipmentoperatingatahighvoltagethatformspartofthegrid.Examplesofprimaryassetsarecircuitbreakersandtransformers

RCP2andRCP3 Thefive-yearregulatorycontrolperiods.RCP2runsfrom1July2015;RCP3beginson1July2020.

reactivepower

Energythatflowsinthepowersystembetweenalternators,capacitors,SVCs,etc,andinductiveandcapacitiveequipmentsuchastransmissionlinesandlowpowerfactorloads.Itistheproductofthevoltageandout-of-phasecomponentsofthealternatingcurrentandismeasuredinvars

relayAdevicedesignedtoproducepredeterminedchangesinoneormoreelectricaloutputcircuits,whencertainconditionsarefulfilledintheelectricalinputcircuitscontrollingthedevice

RIT RegulatedInvestmentTest

R&R Replacementandrefurbishment

SA Secondaryassets

SCADA Supervisorycontrolanddataacquisitionsystem

SMP Standardmaintenanceprocedure

SVC Staticvarcompensator

switchgear Acollectivetermforswitchesofalltypesandtheirassociatedequipment,includingcircuitbreakers,disconnectorsandearthingswitches

synchronouscondenser Asynchronousmachinerunningwithoutmechanicalloadandsupplyoradsorbingreactivepowertoregulatelocalvoltage

TEES TranspowerEnterpriseEstimationSystem,acostestimationsoftware

TL TransmissionLines

transformerAstaticelectricdeviceconsistingofawindingortwoormorecoupledwindingswhichtransferpowerbetweencircuitsofthesamefrequency,usuallywithchangedvaluesofvoltageandcurrent

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