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Transmission and Hybrid SystemsHardware Development

Transmission and Hybrid SystemDevelopment from Concept to Startof ProductionThe automotive transmission has gainedmuch significance in recent years and is akey component in the modern powertrain.Modern vehicle transmissions satisfyexacting demands on driving dynamics aswell as ride comfort, and they reduce fuelconsumption and emissions. Hybridizingthe powertrain provides the capability ofutilizing further potential.

IAV specialists make an important contri-bution to achieving these ambitious goalswith unique synthesis programs for new,optimized transmission structures, aperfected development process, efficientmethods, the systematic use of simulationtools and a broad range of measuring andtesting equipment.

Contact:

Erik Schneider

+49 371 2373-4340

At IAV, more than 270 experiencedengineers – all with excellent qualifications –design, develop, test and integrate trans-missions and their complex control systemson all continents – from the initial idea to theperfected and efficient volume product.

More than twenty-five years of worldwidedevelopment projects with prominentvehicle manufacturers and componentsuppliers, along with innovations, like thestructurally optimized front-transversemodular systems of the 8/9-speed hybriddual-clutch transmission and the 8-speedhybrid automatic planetary transmission,the DualDrive® continuously variable, full-hybrid transmission or the all-electricDrivePacEV80® drive unit, are testimony toour expertise.

Contents

Innovations by IAVDual-Clutch Transmissions (DCT) and Hybrid 4Automatic Transmissions (AT) and Hybrid 6Continuously Variable Transmissions (CVT) and Hybrid 7Electric Drives (eDrives) and Hybrid 8

Engineering by IAVDevelopment Process 10IAV Knowledge Database 12IAV Virtual Drive Simulation 13Systematic, Computer-Aided Transmission Synthesis 14Service Life Computations for Mechanical Components 15Hydraulic Components and Control Units 16Multi-Criteria Optimization of Electric Machines 17Computation and Simulation 18Testing 20

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W e are passionate about devel-oping efficient, production-readyand technologically sophisti-

cated dual-clutch transmissions – whetherhybridized or not. We provide long-standing,key know-how coupled with an efficient,integrated development process from theinitial idea to post-SOP support. Benefitingfrom profound expertise and swift devel-opment pace, our specialists can take careof your project for dry and wet DCT systemsinvolving both hydraulic as well as electri-cally powered actuator systems.

8-speed hybrid DCT for transverseapplications in passenger cars:8H-DCT450• 8 forward speeds and 1 reverse speed• Variable ratio spread between 8.0

and 12.0 • Variable starting ratio between 15.0

and 20.0• 450 Nm / 7,500 rpm input torque / speed• Full hybrid functions with coaxially

integrated electric motor (30 kW / 300 Nm)

• Power-shift clutch to disconnect thecombustion engine

• Highly efficient and demand-matchedmechatronics with double pump andhydraulic accumulator

• Design size comparable to current,conventional 6 and 7-speed DCT

• 9-speed hybrid DCT 9H-DCT450 can bederived with small modifications

IAV DCT concepts with aninnovative edge Transverse application in passenger cars:• 7-speed DCT: 7-DCT280• 8-speed hybrid DCT: 8H-DCT450• 9-speed hybrid DCT: 9H-DCT450

Inline application in passenger cars:• 7-speed DCT: 7-DCT280• 9-speed DCT: 9-DCT300

Motorcycle applications:• 6-speed DCT: 6-DCT115• 7-speed DCT: 7-DCT120

All-terrain vehicle:• 6-speed DCT: 6-DCT140

9-speed hybrid DCT9H-DCT450

9-speed DCT 9-DCT300

6-speed DCT 6-DCT115

Dual-Clutch Transmissions (DCT)and Hybrid

Innovations by IAV

8-speed hybrid DCT 8H-DCT450

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T he many development andintegration projects we havecompleted for clients across the

globe testify to our expertise. Our strengthslie in the interdisciplinary approach ourspecialists take in the work they do onmechanics, hydraulics, software, calibrationand integration. From pinpointing efficientautomatic transmission structures of thenext generation to providing support afterthe start of production and in localization,we cover every link in the value chain. Withour many years of experience, expertiseand process-related knowledge, we are theright address for developing your automatictransmission.

8-speed hybrid AT for transverseapplications in passenger cars:8H-AT350• 8 forward speeds and 1 reverse speed• Variable ratio spread between 6.5 and 8.5 • Variable starting ratio between 16.0

and 18.5• 350 Nm / 6,500 rpm input torque / speed • Mild hybrid functions with integrated

modular electrical motor (basic variant:12.5 kW / 75 Nm)

• Flexible arrangement, size, torque andpower of the electric motor

• Improved hybrid functions from additionaland adaptable ratio between electricmotor and transmission input

• Power-shiftable clutch to disconnect thecombustion engine

• Vehicle start optional by internal shiftelement or torque converter

• Design size is comparable to current,conventional 6-speed AT

IAV AT concepts with an innovative edge Inline application in commercial vehicle:• 9-speed AT: 9-AT3000

Inline application in passenger cars:• 8-speed hybrid AT: 8H-AT500

Transverse application in passenger cars:• 8-speed hybrid AT: 8H-AT350

Automatic Transmissions (AT)and Hybrid

Innovations by IAV

8-speed hybrid AT 8H-AT500

8-speed hybrid AT 8H-AT350 - flexiblearrangement of themodular electric motor

8-speed hybrid AT 8H-AT350

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N umerous clients have come toappreciate our expertise inproviding concepts for conventional

and hybrid continuously variable driveconcepts. As experts in this field, we canshow you how to get the most out of thepotential these transmission systemsharbor, such as convenient power splittingand a suitable number of gear ratio ranges.Whereas the eCVT focuses on minimizingtorque and power on the electric side withacceptable speeds, conventional CVTs facethe challenge of controlling variatoradjustment as well as improving efficiency.

Electric continuously variable trans-mission for transverse applicationsin passenger cars:DualDrive® eCVT350• High driving comfort from the continu-

ously variable gear ratio range forforward and reverse mode

• Highly efficient power split by innovativeand simple 4-shaft planetary gear setwithout shift elements

• 350 Nm / 6,500 rpm input torque / speed • Full hybrid functions with high potential

for plug-in hybrid applications• Optional start-off with power split or

all-electric• Size comparable to current eCVT but with

greater driving dynamics

IAV eCVT concepts with aninnovative edge Transverse application in passenger cars:• Power split eCVT: DualDrive® eCVT350

Inline application in passenger cars:• 8-speed hybrid eCVT: 8H+-eCVT500

Continuously Variable Transmissions (CVT) and Hybrid

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Fuel-saving potentials for a mid-size car(vehicle mass: 1,500 kg / gasoline engine:170 kW / 350 Nm)

DualDrive®eCVT350

8-speed hybrid eCVT 8H+-eCVT500

Electric Drives (eDrives) and Hybrid

Innovations by IAV

R ising noticeably, the demand forelectric vehicles is being encouragedwith financial incentives. For the

future, e-vehicles must be without compro-mises in terms of ecology, cruising rangeand price – while also providing safety,quality, driving pleasure and ride comfort. To meet these demands and exploit all thebenefits of the electric powertrain effec-tively, much of the vehicle concept must bere-defined. This requires a strong andcompetent engineering partner.

The DrivePacEV80 concept devised for thelatest generation of all-electric drive unitshas an integrated wet-running inductionmachine and a power-shiftable planetarygear set, providing high torque with uninter-rupted traction force over a wide speedrange with high energy efficiency rates.

DrivePacEV80 exploits significant potentialin terms of climbing ability, acceleratingperformance and energy efficiency over acomparable single-speed transmission.

Distinguished among other aspects by itsintegration level and scalability, the conceptis shown to be an autonomous drivesolution that can be deployed in variousalternative drive configurations, such as B-EV, FC-EV, H-EV and RE-EV, in differentvehicle segments.

DrivePacEV80 all-electric drive unit Layout of the electric powertrain with accumulator

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IAV DrivePacEV80• Scalable all-electric drive unit • Wet running induction machine with

copper squirrel-cage rotor (300 Nm / 80 kW peak)

• Two-speed power-shiftable planetarygear set

• Output torque up to 3000 Nm• Integrated differential and parking lock• Innovative cooling-system design• Full integration of power electronics,

DC/DC converter and battery charger• Front or rear application• Application in electric vehicles and as an

additional drive for hybrid vehicles

IAV eDrive concepts with aninnovative edge • DrivePacEV80 all-electric drive unit • Hybrid rear-axle with torque vectoring

function

All-electric drive unitDrivePacEV80

All-electric drive unit DrivePacEV80Main mechanical components

Hybrid rear axle forSUV application

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Development Process

W e meet the increasingly complexdemands on the functionalityand efficiency of powertrains

using an effective, perfected and start-to-finish process for developing transmissionsand hybrid systems. Our attention is alsofocused on developing new and derivativetransmissions to the point of mass produc -tion. To do this, our experienced experts indeveloping transmission mechanics,hydraulics and electro-mechanics employstate-of-the-art design and simulation tools– some developed in-house – as well as awide range of CAD and PDM systems. Weuse our particular strengths in optimizing

system level with IAV System Respon-sible Persons (SRP) and IAV ComponentResponsible Persons (CRP)

• High level of flexibility in the type and sizeof work packages using the option withthe best possible prospects of successin terms of development objective,budget and time schedule

• Interdisciplinary product developmentwith a high level of direct responsibility

• Hardware solutions and algorithm devel-opment on a one-stop shop basis

product design: close cooperation with allof the development and production depart-ments involved as well as our vast experi -ence in product-range and suppliermanagement.

• Powertrain development from theadvance-engineering stage to start ofmass production

• Efficient project handling by experiencedspecialists, proven process tool chainand methods, extensive infrastructureand competent project management

• Personal responsibility for engineering,schedule and quality at component and

Engineering by IAV

SystemResponsible

Person

Target management

Design / parts list

Simulation

Change management

Support in testing and approval

Supplier management

Support in manufacturing

Release

Purchasing

Provision and revision of information

Tasks and interaction of IAV System Responsible Person (SRP)

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General overview of development process

Abstract overview of main functional systems

Project management

Mechanics + hydraulics

E-machine + power electronicsRequirementsspecifications

Integrationandcalibration

Software development

Prototype manufacturing

Procurement and quality assurance

Powertrain and vehicle assembly

Gear set

Clutchmodule

Housing Mecha-tronics

Shiftsystem

Electricmachine

Vehicles withconventionalpowertrain

Vehicles withalternativepowertrain

Combustionengines

Customer-specific data

Transmissions

Material

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T he IAV Knowledge Database is adata management and analysis toolfor vehicle and powertrain specifica-

tions. It has the purpose of providingsupport in advance, concept and produc -tion-level development.

The system offers a platform for globalbenchmarking. Modular in form, it can beadapted to any specific application area.One of its key aims is to supply knowledgeon a centralized basis with a view tosecuring an innovative edge. The IAVKnowledge Database is available for ourdevelopment partners and customers topurchase and use.

Fields of knowledgeThe knowledge database sources datafrom trade journals, conferences, onlinecontent / websites, trade and consumerpublications from Europe, Asia and NorthAmerica. Customers can feed in their owndata for comparison with the external dataprovided. The knowledge database alsoincludes information on conventional andalternatively propelled vehicles. The datapool contains facts, figures, characteristiccurves (e.g. full-load curves), characteristicmaps (e.g. fuel consumption maps) anddocuments all of which are available fordirect use. The authorization concept

applied guarantees data security. With theability to set up authorized groups, it ispossible to control access to data andprotect confidential information.

Methods of analysisAn intelligent search tool provides the optionof setting parameters to filter search resultsfor any specific inquiry. Selected vehicles,engines, transmissions etc. are displayed in atable that permits comparison of multiplesearch results. Technical parameters arepresented in point charts (e.g. scatter

bands), bar charts or spider charts. Charac-teristic curves and maps can also be super-imposed for evaluating and visualizingdifferences.

Data exchangeData can be imported into and exportedfrom Microsoft Excel, making easy work offurther processing all search and inquiryresults. External data sources can beimported too (e.g. EPA). Additional inter-faces are available for exchanging data withother IAV computation tools.

IAV Knowledge Database

Flexible analysis features

Architecture of the IAV Knowledge Database

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V irtual Drive Simulation is a softwaretool for simulating the longitudinaldynamics of vehicles. It is suitable

for use in the concept phase as well as forlater analyses of a more detailed nature.The software uses an easy-to-configurepowertrain model provided with predefinedpowertrain topologies. Comprehensiveanalysis permits rapid benchmarking andidentifies trends. The high-performancetool is capable of evaluating a large numberof variants in a short time and supports theuse of multi-criteria optimization.

Analysis capabilities• Consumption, CO2 emissions at varying

or at constant speed• Sprinting and elasticity• Hill-climbing ability and accelerating

performance• Drivability and basic key figures• Potential for start-stop and recuperation

IAV Virtual Drive Simulation

Basis -135 kgVehiclemass

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17,9 %2,7 kWh/100kmPowertrain losses

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Example: Energy saving potentials

Powertrain with two combustion engines

Examples for powertrain topologies

Parallel hybrid powertrain

All-electric powertrain

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Systematic, Computer-AidedTransmission Synthesis

T o develop future transmissionsystems, IAV uses unique, computer-based synthesis programs that

generate all conventional and hybrid trans-mission structures and find the bestsolutions for the application in hand. Thissystematic process allows us to provide ourclients with new, optimized transmission

structures for extremely compact, low-loaded transmissions with high ratio spread,very good gear stepping, simple shift logicfor flexible shift strategies and maximumlevels of efficiency. Generated using clearlydefined methods, the transmissions wegive our customers guarantees the basisfor innovative and competitive volumeproducts.

Transmission types covered• Manual transmissions (MT) with spur

gears• Automated manual transmissions (AMT)

with spur gears• Dual-clutch transmissions with spur

gears• Automatic transmissions (AT) with

planetary gears• Continuously variable transmissions with

conventional (CVT) or electric variator(eCVT)

Generating all combinatorial possibletransmission variants+Analyzing and evaluating conven-tional and hybrid transmissionproperties+Selecting the best transmission for our customer

AT DCT

eDriveeCVT

Sequence of the transmission synthesis forversatile transmission technologies

Engineering by IAV

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Service Life Computations for Mechanical Components

T oday, the need to reduce time andcosts in developing transmissionsmakes it essential to adapt durability

simulations. IAV uses computational soft -ware to predict the lifespan of the entiretransmission system on the basis of loadspectrums that can be generated by simu -lation or obtained from measurement. Thispermits comparison of several concepts atan early stage in the design process as wellas optimization of the preferred solution.The influences from derivative applicationscan also be analyzed, e.g. for hybridizing aconventional powertrain. Dimensioningmachine elements with greater precisionadditionally helps to save time and cutcosts during the testing phase.

Generation of load spectrums • Measuring a real-life cycle with in-vehicle

and data recording• Simulation of longitudinal dynamics

Benefits of the computationprocess• Fast model generation and computation

of the entire system with all machineelements, e.g.- Bearings- Teeth- Shafts- Shaft connections- Shift elements

• Consideration of all interactions and over-determined kinematics

• Overview of all safety factors for nominalload and lifetime for defined loadspectrums

• High potential for optimizing the entiresystem by adapting numerous designparameters

• Clear and extensive documentation for allstrength and lifetime computations

Diverse range of applications• Countershaft transmissions• Planetary transmissions• Continuously variable transmissions with

power split• Conventional, hybrid and all-electric

systems• Bevel differential

Comprehensive computationsfor entire systems

Computation model

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H ydraulic systems are used whenforces and motions need to betransferred with precision, at high

speed and with good efficiency. In auto -motive hydraulics, additional demandsinclude functional intelligence coupled withmaximum efficiency and minimum package.

Our hydraulic systems – in the field of trans-mission management, for example – meet allof these demands. No matter whether it isabout electro-hydraulic pressure supplysystems with multi-stage pumps, solenoidvalves or integrating all components in asingle transmission control module, we canprovide the best possible solution for yourspecific application in terms ofperformance, comfort, durability and cost.

We are experts in other hydraulic actuationsystems as well, such as parking-locksystems or torque-vectoring modules. Alldisciplines are covered on a one-shopbasis, from concept definition to simulation,prototyping and testing.

With state-of-the-art testing equipment,analyzers and laboratory facilities in house,we are also your partner in matters ofcompetitor benchmarking, durability testing,failure analysis and optimization.

Competencies at a glance• Hydraulic control units for automatic and

dual-clutch transmissions• Hydraulic control units for hybrid trans-

missions• Hydraulic transmission components and

actuation systems

• Electro-hydraulic pressure supplysystems

• Pumps• Solenoid valves• Simulation of hydraulic and mechatronic

systems• Various laboratory services and testing

capabilities

Hydraulic Control Unit for Hybrid DCT• High-efficiency, on-demand oil supply• Two-stage pump with separate high and

low-pressure circuits• Direct-acting valves• Hydraulic accumulator in transmission

housing

Hydraulic Components and Control Units

Hydraulic transmission controlunit for hybrid DCT with pressuresupply system and filter

Electro-hydraulic pressure supply system withtwo-stage pump

Control unit for a 2-speed electric drive withpressure supply system

Parking lock

Engineering by IAV

Without optimization With optimization

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With powertrain electrification onthe increase, new electricmachines are needed that

provide greater efficiency at lower cost. Forthis reason, IAV experts have developed aninnovative method that provides thecapability of optimizing various types ofelectric machines, e.g. induction machines,permanent-magnet machines and switchedreluctance machines, in relation to a widerange of different criteria. Computationuses finite element analysis of magneticfield density with subsequent calculation of

relevant losses. Modern computationclusters make it possible to analyze andevaluate extensive parameter variations in avery short time.

Optimization parameters• Machine type• Notch and tooth layout of the metal sheet• Integration and size of air chamber• Arrangement and geometry of magnets• Diameter and length of air-gap• Winding design• Material of iron sheet and magnet

Optimization targets• High-efficiency and torque capacity at

typical operating points • Engine-speed strength• Good performance in field-weakening

range• Low cyclic irregularity• Ease of control • Low material and production costs

Multi-Criteria Optimization of Electric Machines

Efficiency map of a synchronous machine – Potential by optimization

Finite element calculation of the magnetic flux density for different machine types

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Computation and Simulation

C omputation and simulation providethe benefit of obtaining valuableinformation on static strength,

lifespan, noise and vibration at a very earlystage – long before the initial hardware isavailable. Our simulation specialists do thisusing numeric computation and simulationprocesses, such as the finite-elementmethod (FEM) and multi-body simulation(MBS). We are also constantly at work onimproving methods to permit “virtualreleases” – with the aim of reaching theideal situation of only needing to confirmresults at a later stage on the test bench.

FEM Structural Mechanics• Static strength of transmission housing • Tightness of transmission flange /

considering loss of screw preload• Topology optimization

Multi-Body Simulation (MBS)• 1D analysis of torsion vibrations

- Decoupling rotational irregularities (e.g. dual-mass flywheel, centrifugalpendulum absorber)

• Structure-borne and air-borne noise- Vibration amplitudes at mountings- Acoustic velocity of housing surface- Structure-borne sound power- Radiated airborne sound power- Sound pressure at driver’s ear- Psychoacoustics

Tools• MSC.NASTRAN• MSC.ADAMS• ABAQUS • FEMFAT• OPTISTRUCT• IAV-SBNOISE• ITI SIMULATION X• SIMPACK

- Resonance test run during engine start- Full-load and part-load operation in

individual gears- Excitation of gear whine and rattle

• 3D simulation- Dynamic system behavior- Torsion resonance and bending

resonance- Load reversal responses

NVH Behavior• Operational vibrations

- Vibration amplitudes- Vibration acceleration- Dynamic stresses- Campbell diagrams for engine speed

rev-up

1D MBS Model

Engineering by IAV

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Acoustic velocity of transmissionhousing surface

3D MBS modelof engine and transmission

Test center for e-traction systems• Battery-system test bench• Battery-cell test bench• Electric-motor test bench• Transmission system test bench• Battery simulator

Engineering by IAV

Testing

IAV validates all transmissioncomponents and the overall systemOur test specialists measure transmissioncharacteristics from the initial load-collective measurement to the start ofproduction on the basis of specificationrequirements and customer-specific testcriteria. These include function andendurance tests on components, trans-mission systems and entire powertrains,validating resistance to misuse and evalu-ating acoustics. Proceeding from objectivecriteria, we examine and optimize the shiftcomfort of manual transmissions andselection comfort of automatic transmis-sions using the selector shift pedal mea -sure ment system (SSPM) developed by IAV.

We conduct testing on our own testbenches that are equipped with state-of-the-art measurement systems. Validationdrives carried out under extreme conditions(summer, winter, altitude) complement thetest series. Our clients can build on ourengineers’ many years of experience with alltransmission types – particularly in analyzingroller bearings, gearings and synchronizers.

IAV test center for electro-mechanical drives

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Powertrain Test Bench• Function and endurance tests on transmission systems

and entire powertrains• Drive: internal combustion engine• Power output: 535 kW / 2x 3,600 Nm / 3,000 rpm• Hybrid development (150 kW battery simulator)• Dynamics, vibration and rotational-irregularity tests• Controlled resonance (endurance) tests• Simulation of driving dynamics on the test bench• Front or rear-wheel drive

Transmission Test Bench• Function and endurance tests on transmissions systems

and entire drivetrains• Drive: 370 kW / 650 Nm / 10,000 rpm (20,000 rpm)• Output power: 2x 290 kW / 2x 4,200 Nm / 3,000 rpm • Combustion engine simulation • Hybrid development (250 kW battery simulator)• All-electric drive systems • Dynamics, vibration and rotational-irregularity tests• Controlled resonance (endurance) tests• Simulation of driving dynamics on the test bench• Front or rear-wheel drive

Hydraulic Test Bench• Function and endurance test on mechatronic and hydraulic

components• Measurement of oil flow, pressure and driving power /

efficiency analysis • Benchmark analysis • Investigations on cold start, leakage, switching time• Highly dynamic tests / vibration• Temperature range of ambient and fluids -30 to 150°C • Fully automated test cycles or manual tests

Selector shift pedal metrology (SSPM)• Objective investigation into shift comfort of manual

transmissions, automatic and dual-clutch transmissions• Recording pedal characteristics• Verification of subjective anomalies• Examination of specific requirements• Easy installation and removal for fast start-up• Benchmark examination

Powertrain test bench

IAV transmission test rig

Mobile measuring system SSPM

Hydraulic test Bench

IAV GmbHCarnotstrasse 110587 BerlinGERMANY

Tel. +49 30 39978-0Fax +49 30 39978-9790

www.iav.com