ConfigurationThe Volvo Hybrid Driveline consists of four building blocks:• TheVolvoD5KEuro6dieselengine•Electricmotor/generator•VolvoI-Shiftautomatedgearbox•EnergyStorageSystem(ESS)Thehybriddrivelinemakesitpossibletodownsizethedieselengineandinthatwaycontributetofuelsavingscomparedwithconventionalvehicles.ForfurtherdetailsontheD5K enginepleaserefertoitsfactsheet.

Energy Storage System (ESS)TheenergystoragesystemcontainsabatterywithLithium Ioncells.Itweighsapproximately220kg.Thebattery’speakpoweris120kWandenergystoragecapacityis1.2kWh(doublecapacityforarticulatedbuses).Tooperatethebatteryincoldconditionsitisequippedwithaheater.Theheater canbeusedbothwhenthebusisstandingattherampandwhendriving.

Hybrid driveThemostcommonmodeishybriddrive,wherethediesel engineandtheelectricmotortogetherpropelthevehicle. Torqueisdistributedbetweenthetwounitsdependingon theESSchargestatus,speedandotherconditions.

Full electric driveWhenthebusisstandingstillthedieselengineisshutoffduringcertainconditions.Thebuswillthereforetakeofffrom thebusstopinfullelectricmode.Duringthistimethebusis silentandemitszeroemissions.Thedieselenginestartsup atthefirstgearshift.Whenpullingawaywiththeaccelerator pedalpartlypressed,forinstancewhendrivinginslowtrafficqueues,fullelectricdrivecancontinuelonger,untiltheESSchargestatusistooloworifothercircumstancesrequiringdieselenginestart-upoccur.Toenablefullelectricdrive,thebusisequippedwithelectricpowersteering,anelectrical aircompressorandaDC/DCunitthatconverts600Vpowerto24Vpower.TheDC/DCunitreplacestheconventional alternator.

Volvo hybrid drivelineEuro6

the heart of green efficiencyTheVolvoHybridDrivelineisworld-leadinginbothfuelefficiencyanduptime.Thankstotheconceptofparallelhybridpropulsionboththedieselengineandtheelectricdrivecanbeutilizedtotheirfull potential.Hybridtechnologyiswidelyapplicablenotonlyinalltypesofcitytrafficbutalsoinshortercommuterandintercityapplications.Thedrivelineisavailableintwoversions,onewithincreased capacityforarticulatedbuses.

Engine stopped when bus is at a standsillWhenthebusisstandingstillthedieselengineisshut down.Thereareseveralconditionsthatinfluencetheshutdownoftheengine,e.g.thebatterychargelevel,coolanttemperatureandroadgradient.

Iftheenginedoesnotshutdownitstillmeetstherelevant noiseemissionrequirements.Thecrankshaftandcamshaftfeaturerubbervibrationdampers,whichminimizenoiseandvibrations.Fuelpre-injectionisusedtofurtherdampennoisewhenidling.

Brake energy regenerationDuringbrakingorretardationthekineticenergyisregeneratedtochargetheESS.Theregeneratedenergyislaterusedforpropulsionorforauxiliaryconsumerssuchastheaircompressor,DC/DCorairconditioningsystem.

Fuel-efficient with good drivabilityTheVolvoHybridDrivelineisoneoftheworld’smostfuel- efficientdrivelinesforheavydutyvehiclescommercially availableandproveninoperation.TheVolvoD5Kfeaturescommon-railinjectorsandairintakedesignedforoptimumcombustion,whichprovideshighpowerandtorquewithinawiderevrange.Inaddition,theelectricmotoraddsfulltorquefromlowrevs,deliveringapeakofmorethan1200Nminan articulatedbus.Asaresult,theVolvoHybridDrivelineoffersextremelygooddrivabilitywithsupremefuelefficiency.

Volvo hybrid drivelineEuro6

BED00555.13.04EN.Equipmentthatisshownormentionedinthepublicationmaybeoptionaloravailableasanaccessoryandmayvaryfromonecountrytoanother.Weretaintherighttoalterproductspecificationswithoutpriornotification.

Top torque curve Volvo Hybrid Driveline EU6 for two-axle bus

Electric motor and diesel engine

Diesel engine Electric motor

0

200

400

600

800

1000

1200

1400

1600

1800

650 700 900 1100 1300 1500 1700 1900 2100 2300 2500 2700

Engine Speed (rpm)

Tor

que

(Nm

)

Euro 6-compliant through advanced after-treatmentTheVolvoD5Kisalow-emissionengine,intermsofexhaustgasesaswellasnoise.Thelowemissionsareachievedby after-treatmentoftheexhaustgasesusing:• SCR(SelectiveCatalyticReduction)•EGR(ExhaustGasRecirculation)•DPF(DieselParticulateFilter)Thankstotheveryhighefficiencylevelsoftheengineafter- treatmentsystem,emissionsarebelowthelegalrequirements.Theafter-treatmentmodulesareintegratedintheonebox silencerunit.

Volvo I-ShiftTheVolvoI-Shiftisatwelve-speedgearbox.Gearchanging isautomaticandsoftware-controlled.I-ShiftisusedformanydifferentVolvoapplications,butthereisaspecialprogram forhybriddrivelines.Attakeoffthetransmissionprogramfully controlsthedrivelinetooptimizeusageofthedieselengineandtheelectricmotorinparallel.

Duringgearshiftingthetransmissionprogramusesthe electricmotortosynchronizeinputandoutputshaftstospeedupandoptimizethecomfortofthegearshift.Theelectric motorandtheESSarealsousedtoensurethatthetorque interruptionsduringgearshiftingareminimized.

Volvo D5K240 EU6

Max.output 240hp(177kW)

Max.powerat 2200rpm

Max.torquebetween1200–1600rpm 918Nm

No.ofcylinders 4

Bore 110mm

Stroke 135mm

Displacement 5.1dm3

Compressionratio 17.5:1

Oil-changevolume,includingoilfilters approx.18.7L

Volvo I-SAM electric motor

Max.output 120/150kW

Max.torque 800/1200Nm