H. Schreier, B Aliefendioglu, F. Haag | PDIM 2017 | 30 November 2017 | 1Public
POWERTRAIN SOLUTIONS FOR
ELECTRIFIED TRUCKS AND BUSES
PDiM 2017
(Heimo Schreier)Burak Aliefendioglu
Fredrik Haag
AVL
H. Schreier, B Aliefendioglu, F. Haag | PDIM 2017 | 30 November 2017 | 2Public
TRUCK & BUS ELECTRIFICATIONDRIVERS
GHG / CO2 LIMITS ZERO NOISE / EMISSION DRIVING IN CITY ZONES
CO2
URBAN ACCESS REGULATIONS IN EUROPE
FOCUS
OF CURRENT
PRESENTATION
H. Schreier, B Aliefendioglu, F. Haag | PDIM 2017 | 30 November 2017 | 3Public
NEXT GENERATION ELECTRIC TRUCKS WILL CONSIST OF SPECIFIC E-POWERTRAIN
Increasing Production Volumes
Integration of existing components
▪ Low development cost▪ Low validation cost▪ Low production investment▪ Higher product cost
Specific component developments (battery & e-axle)
CURRENT PRODUCTS
NEXT GENERATION
▪ Low product cost▪ Medium development cost▪ Medium validation cost▪ Medium production investment▪ Value-creation in-house
H. Schreier, B Aliefendioglu, F. Haag | PDIM 2017 | 30 November 2017 | 4Public
Modular Battery
Integrated Electric Axle
CONTENT
H. Schreier, B Aliefendioglu, F. Haag | PDIM 2017 | 30 November 2017 | 5Public
BATTERY CHALLENGES IN TRUCK & BUS APPLICATIONS
Charging @ >> P
Discharging @ >> P
Cell Technology
PackDesign
ThermalManagement
BMS
Durability
Volume
Weight
Cost
Range
Energy
Modularity & Scalability
VehicleIntegration
CrashRequirements
H. Schreier, B Aliefendioglu, F. Haag | PDIM 2017 | 30 November 2017 | 6Public
BATTERY CELL TECHNOLOGY
SOP Wh/kg Wh/L
2015 175 - 225 400 - 500
2020 225 - 275 500 - 600
2025 275 - 325 600 - 750
Performance Prognosis of Li-Ion Cells
▪ Li-Ion will remain major technology by mid-term
▪ Li-Sulfur might be an interesting alternative in future
Trends for Automotive-Cell Technology
H. Schreier, B Aliefendioglu, F. Haag | PDIM 2017 | 30 November 2017 | 7Public
BEST COST AND HIGHEST FLEXIBILITY BY MODULAR RACK DESIGN
from cell to moduleRACK SYSTEM ENABLES:▪ Scalability▪ Modularity▪ Ease of assembly▪ Re-usability with different
modules▪ Flexible pack design and
vehicle integration
(a) Longitudinal (b) Transverse (c) Sideways (d) Inverted
H. Schreier, B Aliefendioglu, F. Haag | PDIM 2017 | 30 November 2017 | 8Public
BEST COST AND HIGHEST FLEXIBILITY BY MODULAR RACK DESIGN
CoolingPlates
RackStructure
LargeRack
SmallRack
Scalable and modular pack concept
H. Schreier, B Aliefendioglu, F. Haag | PDIM 2017 | 30 November 2017 | 9Public
E/E CONCEPT MODULARITY IN VOLTAGE AND ENERGY
Configuration with 432 cells
36 modules in series with 12 cells each
6S2P = 800V
3S4P = 400V
Configuration with 864 cells
72 modules in series with 12 cells each
3S4P = 800V
5x + 3x
3x
VARIABLE MODULE CONFIGURATION ALLOW EASY VOLTAGE ADJUSTMENT12S1P - 6S2P - 4S3P - 3S4P
H. Schreier, B Aliefendioglu, F. Haag | PDIM 2017 | 30 November 2017 | 11Public
MOST EFFECTIVE COOLING IS KEY FOR HIGH PERFORMANCE BATTERIES
Highway Transport Cycle
• Temperature spread kept <10K
• Pack temperature kept at 30°C
Urban Transport Cycle
• Temperature spread kept <<10K
High Performance Charging
• 15°C increase at 1.5C charge rate
Vehicle Load Cycle
System Simulation
Battery System Response
THERMAL SİMULATİON RESULTS
REQUIRES PRECISE
THERMAL MANAGEMENT
& SMART CONTROLS
Current [A] Electrical Power [kW] SoC [%] Voltage [V]
Cell
Tem
peratu
re [
°C
]
H. Schreier, B Aliefendioglu, F. Haag | PDIM 2017 | 30 November 2017 | 12Public
MODULAR BATTERY MANAGEMENT SYSTEM
AVL MCU & AVL BMS (3rd generation)
▪ MOST ACCURATE BATTERY/CELL STATE CONTROL - for highest performance & durability
▪ MODULAR PLATFORM & MODEL BASED CONTROLS – for efficient handling of variants
▪ FLEXIBLE ADAPTION TO CUSTOMERS REQUIREMENTS including open-source SW
Function Overview – AVL BMS
CORE BATTERY FUNCTIONS
▪ State of Charge (SOC)
▪ State of Health (SOH)
▪ Balancing
▪ State of Function (SOF)
▪ Cell failure / wear detection
AUXILIARY FUNCTIONS
▪ Start-up / Shutdown
▪ Signal acquisition / actuator control
▪ Main contactor control
▪ Pre-charge function
▪ Thermal management
INTERFACE & COMMUNICATION
▪ Vehicle interface
▪ Diagnosis interface
▪ Logistic-information
▪ Actuator control (external)
▪ Re-programming
SAFETY & DIAGNOSIS
▪ Isolation detection
▪ HV interlock
▪ Safety monitoring
▪ Diagnosis functions
▪ Error-management
H. Schreier, B Aliefendioglu, F. Haag | PDIM 2017 | 30 November 2017 | 13Public
EXAMPLES OF A BATTERY PACK FAMILY FOR LD & MD TRUCK
LD Pack
MD Pack
Number of modules - 36 72
Module configuration - 6S2P 3S4P
Cell weight kg 374 748
Pack weight kg 575 1.150
Nominal voltage V 800 800
Installed energy kWh 112 223
Usable energy kWh 78 156
Power – continuous kW 235 420
Power - peak kW 400 715
LD Battery Pack112 kWh
MD Battery Pack223 kWh
H. Schreier, B Aliefendioglu, F. Haag | PDIM 2017 | 30 November 2017 | 14Public
Modular Battery
Integrated Electric Axle
CONTENT
H. Schreier, B Aliefendioglu, F. Haag | PDIM 2017 | 30 November 2017 | 15Public
SELECTION OF E-AXLE ARCHITECTURE
OBJECTIVES / BOUNDARIES:
▪ Small packaging space for battery
▪ High system efficiency avoid bevel-gear set
▪ Low cost & weight
▪ High integration level
▪ Low number of interfaces reliability, assembly complexity
Center Drive
Axle Integrated
Drive
WheelSelective
Drive
Most Suitable e-Axle architectures for HD Truck
H. Schreier, B Aliefendioglu, F. Haag | PDIM 2017 | 30 November 2017 | 16Public
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Gross Vehicle Weight: 16 tons
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Gross Vehicle Weight: 16 tons
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Gross Vehicle Weight: 16 tons
gear 2 (cont.)
gear 1 (cont.)
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Gross Vehicle Weight: 16 tons
gear 2 (cont.)
gear 1 (cont.)
gear 1 (peak)
▪ Definition of continuous power of E-motor
▪ Gradeability: 2.2% at 80kph
▪ Good performance also for city highways
▪ Resulting continuous power of E-machine: 148kW
▪ Definition of number of gears
▪ Maximum vehicle speed: 88kph
▪ City highways
▪ Reduced E-motor speed for 80kph
▪ Maximum gradeability: 16% + 0.3m/s² acceleration
▪ Relevant urban transport routes
▪ Artificial ramps
▪ Resulting number of gears: 2 gears
SYSTEM SPECIFICATION:E-MOTOR POWER AND NUMBER OF GEARS
2.2%@80kph
max. 18.8%= 16 % + 0.3 m/s² acceleration
H. Schreier, B Aliefendioglu, F. Haag | PDIM 2017 | 30 November 2017 | 17Public
SELECTION OF E-MOTOR TYPE
Parameter IM PSM
Power / torque density 0 ++
Overload capability + 0
Cost + -
Robustness ++ 0
Failure torque + -
Efficiency at high speed + 0
Efficiency at mid speed - +++
High Efficiency Areas
Torque
Speed
PSM
IM
PSM technology show overall best performance for this application
Comparison of efficiency maps
Induction vs. Permanent Synchronous Motor
H. Schreier, B Aliefendioglu, F. Haag | PDIM 2017 | 30 November 2017 | 18Public
HIGH E-MOTOR PERFORMANCE BY DIRECT OIL-COOLING OF STATOR
▪ E-Motor is typically laid-out / designed for peak power
▪ Continuous power depends on effectiveness of cooling system
▪ AVL direct oil-cooling of stator enables highest continuous-power densities
Uncooled,Free
convection
Aircooled
Water jacket
Forced air
convection
Direct oil-
cooling
Peak Power
Continuous-power output of different cooling concepts
continuous-power output
E-M
oto
r P
ow
er
AVL direct oil-cooling of windings
Integration of AVL e-motor into e-axle
H. Schreier, B Aliefendioglu, F. Haag | PDIM 2017 | 30 November 2017 | 19Public
DEFINITION OF E-MOTOR SPEED
Inverter▪ Suitable inverter output
frequency
Transmission▪ Standard components▪ Suitable ratios without
additional gear mesh
E-Motor▪ Low torque => high speed
▪ Low cost▪ Compact packaging
E-Motor
Continuous power (kW) 148
Maximum speed (rpm) 16.000
Continuous torque (Nm) 265
Number of pole-pairs (-) 3
Corner speed ratio (-) 1:3
Inverter
Inverter output frequency (Hz) 800
Transmission
Ratios (1st gear/2nd gear) ~50/30
gear meshes (incl. differential) 3
Technology (bearings, seals) Standard
Balance
of
Parameters
H. Schreier, B Aliefendioglu, F. Haag | PDIM 2017 | 30 November 2017 | 21Public
▪ Mechanical and thermal integration for high vibration
environment
▪ Usage of standard semiconductor modules
(1.200 V IGBT, max. 600 A / phase)
▪ High efficiency by specific DC-link capacitor design
▪ Modular / scalable platform
▪ Easy adaption to available packaging
▪ Easy assembly & service
▪ EMC advantages due to bus bar AC- & DC-connections
▪ Transmission control integrated in power electronics
▪ Electronics fully integrated in axle body
(cost, weight and reliability advantage)
INVERTER DESIGN
H. Schreier, B Aliefendioglu, F. Haag | PDIM 2017 | 30 November 2017 | 22Public
TRANSMISSION DESIGN
TRANSMISSION OPTIONS:
▪ Layshaft
▪ Planetary
▪ Combination of both
TARGETS / EVALUATION CRITERIA:
▪ Suitable gear ratios
▪ Small packaging / short axial length
▪ Highest efficiency
▪ Lowest cost
▪ Variable arrangement / modularity
Selected Topology:
▪ Layshaft arrangement
▪ 2 speeds
▪ 3 gear meshes
▪ Conventional differential
H. Schreier, B Aliefendioglu, F. Haag | PDIM 2017 | 30 November 2017 | 23Public
CHALLENGES:
▪ Different temperature levels required for inverter, e-motor and transmission
▪ Reliable lubrication of high-speed transmission
COOLING & LUBRICATION SYSTEM
Oil Circuit 1 (externally cooled)
Oil Circuit 2
M
Heat transfer to environment
Heat transfer to environment
Heat transfer trough axle body
SOLUTION:
▪ Separate oil circuits for
▪ Lubrication of transmission
▪ Cooling of inverter and e-motor
ADVANTAGES
▪ Optimized component temperatures (Efficiency)
▪ Reliable lubrication of high-speed transmission
▪ High-performance transmission oil possible
▪ Compact design
H. Schreier, B Aliefendioglu, F. Haag | PDIM 2017 | 30 November 2017 | 24Public
E-MACHINE
Type PSM
Voltage level [V] 800
Continuous power [kW] 148
Max. continuous torque [Nm] 265
Max. speed [rpm] 16.000
Cooling systemDirect statorOil-cooling
TRANSMISSION
Transmission type Layshaft
Number of gears 2
Max. output torque [Nm] 13.200
148 KW ELECTRIC AXLE FOR 16 TON ELECTRIC URBAN TRUCK
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Grad
eab
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%]
Velocity [km/h]
2nd gear - continuous
1st gear - continuous
2nd gear - peak
1st gear - peak
Vehicle Performance - 16 ton Truck (4x2)
H. Schreier, B Aliefendioglu, F. Haag | PDIM 2017 | 30 November 2017 | 25Public
▪ Demand for zero-emission transport solutions will further increase
▪ Next generation e-trucks and e-buses will implement specific CV-systems
▪ Frame-integrated batteries improve crash-safety, cost and weight
▪ Integrated electric axles provide space for battery packaging and improve efficiency, cost and weight
▪ Modularity & scalability is key to cover different applications
CONCLUSIONS
H. Schreier, B Aliefendioglu, F. Haag | PDIM 2017 | 30 November 2017 | 26Public
FULLY INTEGRATED E-DRIVE FOR SUVHIGHLY EFFICIENT AND HIGHLY INTEGRATED
SPECIFICATIONS
Highlights ▪ Full integrated power inverter
▪ High efficient oil stator cooling
▪ PSM – high speed concept with 20.000 rpm
▪ EMC optimized
Operating voltage 800 V
Power (cont./peak) 150 kW / 230 kW
Torque (cont./peak) 240 Nm / 360 Nm
Dimensions 544 x 387 x 280 mm
Weight overall (approx.) < 100 kg
Power to weight ratio > 2.3 kW/kg
Cooling concept Oil, water or combined