Energy Bank Capacitor Applications

Table of Contents

• Introduction

• Electrical parameters • Energy • Peak current (discharge voltage) • Voltage ripple • Pulse Current • Principle • Pulse Forming Network

• AVX realizations • AVX Knows How •DCfilteringforindustrialapplication •Reasonancefiltersforrailwayssubstations •DCfilterforpowerelectronictube •PulseFormingNetworkforHIghPowerLASER •DCEnergystoragefor50/60Hzconverter •DCEnergystorageforSmootherfilter •DCEnergystorageforPowerSystemBooster •DischargeEnergyBankforElectromagneticgun

•GuideforCustomer’sSpecificRequirements

1

Introduction

HighPowercapacitorscanbeidentifiedasstoragevolume.Atankwillstoragewaterdrop,capacitorswillstorageelectricalcharge(electrons).

Everybodyknowswhatisadamorfloodbarrieroratoiletflush,EnergyStorageCapaci-torwillactasdamortoiletflush

Theprincipleofworkingisa“long”chargetimeanda“short”dischargetimeinordertogenerate a short pulse with peak current

Shortpulsewithpeakcurrentwillproduceahighpowerpulseabletocreate:-highmagneticfieldininductances-ormagneticfieldinmagnets- or an ionization in a lamp - or a plasma in the material- or EM pulse lightning -orHighFrequencytubes

Applicationsaremultiplesbutsomeofthemarewellidentifiedas: -particlesacceleratorsinResearchLabs -EMgunsforMilitaryapplications -FusionLaserforMilitaryapplications -HighMagneticfieldforResearch(Medical) -MarxGeneratorforMilitaryapplicationsandElectricalLabs - EM cylinders - Electrical Forming -KlystronsandotherHighPowerelectronictubes

SomeothersclassicalapplicationsDCbanksfilteringinstorageHighEnergyapplicationaremetforTransport&DistributionofEnergy(FlexibleACTransmissionSystem,STAticCOMpensator,UnifiedPowerFlowController).

Moreandmore,banksofcapacitorsareusedasEnergystoragebanksinordertodeliv-erenergyduringseveral100ms.Contrarytobatteriesandsupercapacitors,powerca-pacitorshavenolimitationintermofdischargetime.

TheseHighEnergyapplicationsrequestnotonlyfewelementarycapacitorsbutlotofcapacitorsmechanicalmountedandelectricalconnectedonmechanicalframes.

2

Electrical Parameters

II.1.Energy

PowerrangemeansseveralkVand“High”capacitanceinordertogenerate“High”energyfrom100kJuptoseveralMJperequipment.Themaxelementarycapacitanceisabout125kJperunit.

Werememberthat:Energy=½CV²(withEinJoule,CinFandVinVolt).

II.2.PeakCurrent(dischargevoltage)

IfPeakCurrentisproportionaltocapacitance,currentdependsalsoofratiobetweenvoltageandtimeofdischarge.Dependingofapplications,PeakCurrentcanshiftfromfewkAuptoseveralMA.

Werememberthat:Ipeak=C∆V/∆t(withIpeakinAmps,CinF,VinVoltandtinsecond) AnexampleforenergybankC=10x300µF/24kV

3

Electrical Parameters

Theenergybankwilldischargeitselfpartiallyabout80%during500ms.Thisdischargecanberepeatseveraltimesperdayorfewtimespermonth.Thetargetistopresentenergystorageavailableincaseofswitchingorshorttimedisruption.Inthiscasebatteriesorsupercapacitorscannotprovidethisenergyduringthistime,electrolyticcapscannotbeusedduetohighvoltageandhighenergyandsecurityofworking.

II.4.PulseCurrent

II.4.1.Principle

Capacitor(C)chargeordischargeisfirstordermode,exponentiallawin serialresistance(R).Ifinthecircuitweaddaninductance(L),atminimum thereisalwaysinductanceduetoserialinductanceofcapandinductance ofconnections,thechargeanddischargemodewillbesecondorderwith sinewavesofcurrentandvoltage.

II.3.VoltageRipple

4

AR,L,Ccircuitcangenerateonlysinewavespulsebutsometimes,theloadrequestsquarepulses,it’sthecaseofmagnetron,klystronormagnets. Inthiscaseit’snecessarytouseaPFN(PulseFormingNetwork).

II.4.2.PulseFormingNetwork

APFN,isrealizedwithL,Ccells,sameasdelayline,butthePFNischargeanddischargedinitsentranceonitscharacteristicimpedanceinordertogenerateasquarecalibratedpulsewithoutreversal.Squarepulsehavespecificcharacteristicsas:risetime,falltime,overshoot,ripple,rampthatTPCcontrolwithcellscharacteristics.TPCisatheonlyonecompanytodesignandtomanufacturePFN.

5

III.TPCrealizations

III.1.TPCKnowHow

TPChasmore47yearsofexperienceinelectrotechnicfield,theusualvaluesarekiloVoltxkiloAmps=MegaWatt.Sizeofsuchapplicationsinduceseveralm3andseveraltons.TPCKnowHowistodesignsuchcomponentsmeetingelectricalandmechanicalfunctions.TPCisalsoabletodesignmechanicalstructuresupportingcapacitors,electricalinsulation,connectionsandcabling.

III.2.DCfilteringforindustrialapplication

Dependingofpowerapplication,whenonereachseveralMW,severalDCcapacitorsareconnectedinparallel.

III.2.1.Resonancefilterforrailwayssubstations

C2943:2175µF+/-2%-6.2kV-220kg

6

III.2.2.DCfilterforpowerelectronictube

TFL118:160µF+/-10%-32kV–1250kg

L1296:500µs–58kV–1.5MW–23000kg

7

III.4.DCEnergystoragefor50/60Hzconverter

C2961:74000µF+/-5%–4.2kV–4500kg

Nota:Totalbankperconverteris0.28F/4.2kV

8

III.5.DCEnergystorageforSmoothfilterforelectromagnets(SynchrotronPowerSupply)

C2953:400.000µF+/-5%-1650V–1500kg

Nota:thesecabinetshavebeendesignedandrealizedwithadditionalcontrol/commandfunctionsas:- Thermal measurements- Zero Voltage Testing- Securitysystem- ProgrammableLogicComputer

9

III.6.DCEnergystorageforPowerSystemBoosterforMagnetssupplyforProtonSynchrotron

C2955:64575µF+/-2.5%-5kVdc–3450kg

Nota:thetotalbankis0.25F/5kVdcworkinginmarinecontainers

10

III.7.DischargeEnergyBankforElectromagneticgun(Militaryapplications)

C2931:0.17F+/-10%-10.75kV–29000kg

11

Customer’s Specific Requirements

Company / Name / Email / Phone Project / Quantity

Capacitors IntegrationCapacitors Dimensions (mm) Operating Position Terminals

length width hight vertical Type Number

horizontal

Bank InformationBank available volume (mm) Insulation level (k V rm s)

length width hight form0V fromgground

Thermal CharacteristicsStorage temperature (ºC) Operating Temperature (ºC) Coolingmin min Natural Convection

average Average Foreced Air

max max

Remarks

Applications DC Application Discharge ApplicationTotalCapacitance(µF)

Tolerance(%)

Operating coltage (ripple included)

Ripple voltage (peak to peak)

Workingfrequency(Hz)

Peak current

RMScurrent

Maximumcurrent/duration

Discharge

Pulseduration@5%lpeak(µs)

Time to lpeak (µs)

RingingFrequency(Hz)

ReversalVoltage(%)

Repetition rate

Holdtime@fullvoltage(s)

Faultpeakcurrent/nbshots

Faultreversalvoltage(%)

Lifetimeexpectancy

Maximum Inductance (nH)

Testvoltagebetweenterminals(kV)

Testvoltagebetweenshortedterminalsandcase(kV)

MaximumsurgevoltageMSV(kV)

MSVDuration/Frequency second /year

http://www.avx.com

Contact:

NORTH AMERICA

SOUTH AMERICA

ASIA

JAPAN

EUROPETel: 864-967-2150 Tel: +44 1276-697000 Tel: +65 6286-7555

Tel: +81 740-321250Tel: +55 11-46881960