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 1
TRUCK & BUS ELECTRIFICATION DRIVERS CO 2 URBAN ACCESS REGULATIONS IN EUROPE FOCUS OF CURRENT PRESENTATION GHG / CO2 LIMITS ZERO NOISE / EMISSION DRIVING IN CITY ZONES H. Schreier, B Aliefendioglu, F. Haag PDIM 2017 30 November 2017 2
NEXT GENERATION ELECTRIC TRUCKS WILL CONSIST OF SPECIFIC E-POWERTRAIN Integration of existing components NEXT GENERATION Specific component developments (battery & e-axle) Increasing Production Volumes Low development cost Low validation cost Low production investment Higher product cost CURRENT PRODUCTS 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 3
CONTENT Modular Battery Integrated Electric Axle H. Schreier, B Aliefendioglu, F. Haag PDIM 2017 30 November 2017 4
BATTERY CHALLENGES IN TRUCK & BUS APPLICATIONS Crash Requirements Volume Weight Range Vehicle Integration Cell Technology Discharging @ >> P Pack Design Charging @ >> P BMS Cost Modularity & Scalability Thermal Management Energy Durability H. Schreier, B Aliefendioglu, F. Haag PDIM 2017 30 November 2017 5
BATTERY CELL TECHNOLOGY Trends for Automotive-Cell Technology Li-Ion will remain major technology by mid-term Li-Sulfur might be an interesting alternative in future 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 H. Schreier, B Aliefendioglu, F. Haag PDIM 2017 30 November 2017 6
BEST COST AND HIGHEST FLEXIBILITY BY MODULAR RACK DESIGN from cell to module RACK 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 7
BEST COST AND HIGHEST FLEXIBILITY BY MODULAR RACK DESIGN Cooling Plates Scalable and modular pack concept Rack Structure Large Rack Small Rack H. Schreier, B Aliefendioglu, F. Haag PDIM 2017 30 November 2017 8
E/E CONCEPT MODULARITY IN VOLTAGE AND ENERGY Configuration with 432 cells Configuration with 864 cells 3x 36 modules in series with 12 cells each 6S2P = 800V 3S4P = 400V 5x + 3x 72 modules in series with 12 cells each 3S4P = 800V VARIABLE MODULE CONFIGURATION ALLOW EASY VOLTAGE ADJUSTMENT 12S1P - 6S2P - 4S3P - 3S4P H. Schreier, B Aliefendioglu, F. Haag PDIM 2017 30 November 2017 9
Cell Temperature [ C] MOST EFFECTIVE COOLING IS KEY FOR HIGH PERFORMANCE BATTERIES Vehicle Load Cycle THERMAL SİMULATİON RESULTS System Simulation Battery System Response Highway Transport Cycle Temperature spread kept <10K REQUIRES PRECISE Pack temperature kept at 30 C THERMAL MANAGEMENT Urban Transport Cycle Temperature spread kept <<10K & SMART CONTROLS High Performance Charging 15 C increase at 1.5C charge rate Current [A] Electrical Power [kw] SoC [%] Voltage [V] H. Schreier, B Aliefendioglu, F. Haag PDIM 2017 30 November 2017 11
MODULAR BATTERY MANAGEMENT SYSTEM SAFETY & DIAGNOSIS Isolation detection HV interlock Safety monitoring Diagnosis functions Error-management 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 AVL MCU & AVL BMS (3 rd generation) Function Overview AVL BMS 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 H. Schreier, B Aliefendioglu, F. Haag PDIM 2017 30 November 2017 12
EXAMPLES OF A BATTERY PACK FAMILY FOR LD & MD TRUCK LD Pack MD Pack Number of modules - 36 72 MD Battery Pack 223 kwh 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 Pack 112 kwh H. Schreier, B Aliefendioglu, F. Haag PDIM 2017 30 November 2017 13
CONTENT Modular Battery Integrated Electric Axle H. Schreier, B Aliefendioglu, F. Haag PDIM 2017 30 November 2017 14
SELECTION OF E-AXLE ARCHITECTURE Center Drive Axle Integrated Drive OBJECTIVES / BOUNDARIES: Small packaging space for battery High system efficiency avoid bevel-gear set Low cost & weight High integration level Wheel Selective Drive Most Suitable e-axle architectures for HD Truck Low number of interfaces reliability, assembly complexity H. Schreier, B Aliefendioglu, F. Haag PDIM 2017 30 November 2017 15
Gradeability [%] SYSTEM SPECIFICATION: E-MOTOR POWER AND NUMBER OF GEARS 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 36 32 28 24 20 16 12 8 4 0 Gross Vehicle Weight: 16 tons max. 18.8% = 16 % + 0.3 m/s² acceleration gear 2 (cont.) gear 2 (cont.) gear 1 (cont.) gear 1 (peak) (cont.) 2.2%@80kph 0 10 20 30 40 50 60 70 80 90 Velocity [kph] H. Schreier, B Aliefendioglu, F. Haag PDIM 2017 30 November 2017 16
SELECTION OF E-MOTOR TYPE Induction vs. Permanent Synchronous Motor Torque Parameter IM PSM Power / torque density 0 ++ Overload capability + 0 High Efficiency Areas Cost + - Robustness ++ 0 Failure torque + - Efficiency at high speed + 0 Efficiency at mid speed - +++ PSM IM Comparison of efficiency maps Speed PSM technology show overall best performance for this application H. Schreier, B Aliefendioglu, F. Haag PDIM 2017 30 November 2017 17
E-Motor Power HIGH E-MOTOR PERFORMANCE BY DIRECT OIL-COOLING OF STATOR Peak Power continuous-power output Uncooled, Free convection Air cooled Water jacket Forced air convection Direct oilcooling Continuous-power output of different cooling concepts AVL direct oil-cooling of windings Integration of AVL e-motor into e-axle 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 H. Schreier, B Aliefendioglu, F. Haag PDIM 2017 30 November 2017 18
DEFINITION OF E-MOTOR SPEED Transmission Standard components Suitable ratios without additional gear mesh E-Motor Low torque => high speed Low cost Compact packaging Balance of Parameters Inverter Suitable inverter output frequency 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 (1 st gear/2 nd gear) ~50/30 gear meshes (incl. differential) 3 Technology (bearings, seals) Standard H. Schreier, B Aliefendioglu, F. Haag PDIM 2017 30 November 2017 19
INVERTER DESIGN 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) H. Schreier, B Aliefendioglu, F. Haag PDIM 2017 30 November 2017 21
TRANSMISSION DESIGN TRANSMISSION OPTIONS: Layshaft Planetary Combination of both Selected Topology: Layshaft arrangement 2 speeds 3 gear meshes Conventional differential TARGETS / EVALUATION CRITERIA: Suitable gear ratios Small packaging / short axial length Highest efficiency Lowest cost Variable arrangement / modularity H. Schreier, B Aliefendioglu, F. Haag PDIM 2017 30 November 2017 22
COOLING & LUBRICATION SYSTEM CHALLENGES: Different temperature levels required for inverter, e-motor and transmission Reliable lubrication of high-speed transmission SOLUTION: Separate oil circuits for Lubrication of transmission M Cooling of inverter and e-motor ADVANTAGES Optimized component temperatures (Efficiency) Reliable lubrication of high-speed transmission High-performance transmission oil possible Compact design Heat transfer to environment Oil Circuit 1 (externally cooled) Heat transfer trough axle body Heat transfer to environment Oil Circuit 2 H. Schreier, B Aliefendioglu, F. Haag PDIM 2017 30 November 2017 23
Gradeability [%] 148 KW ELECTRIC AXLE FOR 16 TON ELECTRIC URBAN TRUCK 36 32 2nd gear - continuous 1st gear - continuous 28 2nd gear - peak 24 1st gear - peak 20 16 12 8 4 0 0 10 20 30 40 50 60 70 80 90 Velocity [km/h] Vehicle Performance - 16 ton Truck (4x2) E-MACHINE Type PSM Voltage level [V] 800 Continuous power [kw] 148 Max. continuous torque [Nm] 265 Max. speed [rpm] 16.000 Cooling system Direct stator Oil-cooling TRANSMISSION Transmission type Layshaft Number of gears 2 Max. output torque [Nm] 13.200 H. Schreier, B Aliefendioglu, F. Haag PDIM 2017 30 November 2017 24
CONCLUSIONS 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 H. Schreier, B Aliefendioglu, F. Haag PDIM 2017 30 November 2017 25
FULLY INTEGRATED E-DRIVE FOR SUV HIGHLY 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 Power (cont./peak) Torque (cont./peak) Dimensions Weight overall (approx.) Power to weight ratio Cooling concept 800 V 150 kw / 230 kw 240 Nm / 360 Nm 544 x 387 x 280 mm < 100 kg > 2.3 kw/kg Oil, water or combined H. Schreier, B Aliefendioglu, F. Haag PDIM 2017 30 November 2017 26
ZERO-EMISSION SOLUTIONS FOR URBAN TRANSPORT THANK YOU FOR YOUR ATTENTION H. Schreier, B Aliefendioglu, F. Haag PDIM 2017 30 November 2017 27