From 12+12V to 48V: a new road map for hybridization
Transcription
From 12+12V to 48V: a new road map for hybridization
Powertrain Systems From 12+12V to 48V: a new road map for hybridization Dr. Ing O. COPPIN - Valeo Powertrain Systems - France May - June 2016 Engine Expo 2016 - Stuttgart Property of Valeo – Duplication Prohibited Engine Expo 2016 - Stuttgart May - June 2016 I 1 Agenda 1 Drivers for Hybridization 2 12+12V & 48v mild hybrid functions 3 Introduction to Boosted Hybrid 4 Hybridization effects on Nox emissions 5 Electrical board net modular architectures 6 Components modularity 7 12+12V & 48v extending Road-Map 8 Conclusion Property of Valeo – Duplication Prohibited Engine Expo 2016 - Stuttgart May - June 2016 I 2 Driver for hybridization : CO2 regulations Main Issue of Hybrid / Electric: COST! 12000 Cost of Powertrain (€) 48V Systems 10000 China 2020 (cars only):106 8000 6000 12V Systems 4000 2000 0 Gasoline STT Diesel STT Gasoline 12+12V Gasoline MH 48V Gasol. Mild 100V HEV 300V PHEV 10km PHEV 40km BEV REX Diesel today just represent the upper limit customers are willing to pay To develop in mass-market, Hybrids need to be cheaper : Why 12V+12V and 48V make sense Property of Valeo – Duplication Prohibited Engine Expo 2016 - Stuttgart May - June 2016 I 3 Hybrid functions Functions Stop & Start Extended SST & Coasting Energy recovery Supply board net Torque assist Boost Property of Valeo – Duplication Prohibited HV 48V 12+12V 12V Engine Expo 2016 - Stuttgart May - June 2016 I 4 Alternative Boosting : efficiency analysis Mechanical supercharger Electrical supercharger 17,4 100 > 100 100 > 82,6 High mechanical losses, only 82% of generated torque goes to the wheels No Mechanical losses. 100% of the generated torque is transferred to the wheels With e-Supercharger there is no friction while boosting. Energy is free while recovered during braking Property of Valeo – Duplication Prohibited Engine Expo 2016 - Stuttgart May - June 2016 I 5 Interest of alternative boosting Hybrid system 25 kW Electrical supercharger 25kW To get 25kW on the wheels, need ~25 kW from the e-motor. With 300Amps limit , 100V necessary 5 kW 25kW To get 25kW on the wheels, need ~5 kW on the air thanks to combustion COP. With 300Amps limit , 48V is far enough With e-Supercharger there is fundamentally efficiency benefit linked to combustion COP For the same power at wheels, the hybrid voltage can be reduced from high voltage to 12 or 48V: The electric system, including batteries, is then far cheaper. Property of Valeo – Duplication Prohibited Engine Expo 2016 - Stuttgart May - June 2016 I 6 Electric Supercharger = instantaneous response 26 24 BMEP (bar) 22 Electric supercharger after 0.5s Turbo engine Turbo after 2.0s 20 18 Turbo after 1.0s 16 Turbo after 0.5s 14 12 Naturally aspirated engine 10 8 500 1500 2500 3500 Engine speed (RPM) 4500 5500 6500 The higher the downsizing, the longer the turbo lag @ low RPM. The turbo is unable to compensate the lag. Response time is the key parameter Property of Valeo – Duplication Prohibited Engine Expo 2016 - Stuttgart May - June 2016 I 7 Electric Supercharger – 3 main application fields More Power Audi RS5 TDI 386HP Volvo eDrive 450HP 48V Property of Valeo – Duplication Prohibited Less pollutants Better Fuel Efficiency Valeo NA Democar 8% FE Ricardo HyBoost 20% FE Valeo-FEV : Euro6 w/o SCR 12V Diesel Engine Expo 2016 - Stuttgart May - June 2016 I 8 Electric Supercharger - Various Applications Allows downspeeding without response drawback (Valeo Democar 8% Fuel economy) Allows Miller Cycle operations on NA engine Allows extreme downsizing (Suralhy Democar & Ricardo’s HyBoost DemoCar 20% Fuel economy better performances) Allows boosted EGR Allows low cost hybridization while coupled with regen system (Kia’s “T- Allows exceptional accelerations on premium sporty vehicles (Audi RS5, Acura Hybrid” concept in Paris 2014) NSX) Allows Clean Diesel without SCR Property of Valeo – Duplication Prohibited Allows enhanced cylinder disconnection Engine Expo 2016 - Stuttgart May - June 2016 I 9 NOx emissions reduction with iBSG – Valeo Internal study C-Segment MPV (1430kg), 1.6L Diesel, 6-Speed MT, no Stop&Start Simulation estimates (warm start) Possibility to tune iBSG between CO2 and NOx Acceleration scenario with torque assist -25%* -80%* NOx emissions Fuel consumption Speed 30 to 60km/h at 2m/s², in 3rd gear Benefits from electric assistance (belt starter-generator used at max. torque): BSNOx CO2 / NOx benefit [%] 30 Optimization tradeoff: 90% CO2 – 10% NOx 10.00 CO2 benefit [%]* NOx benefit [%]* 24.0 20 10 20.3 14.5 15.8 6.8 3.2 0 NEDC WLTC RDE-like NOx emissions variation [%]* Driving cycles Reduction of engine high load operation by electric assistance Possibility to tune CO2 / NOx Tradeoff Improved vehicle response Engine operated in low NOx regions RDE-like cycle 0.00 Conv. -10.00 iBSG – NOx optimized -20.00 -30.00 -40.00 -5 -2.5 0 2.5 CO2 emissions variation [%]* * Valeo estimate, non contractual data, pending applications, will vary per vehicle application Property of Valeo – Duplication Prohibited Engine Expo 2016 - Stuttgart May - June 2016 I 10 5 NOx emissions reduction with eSC - Valeo based on FEV / Valeo study Engine 2.0L Diesel, Simulation estimation Context: During transient, NOx emissions increases due to the lack of fresh air. By instantaneously increasing the air flow, the eSC lower the NOx increase in transient. BMEP [bar] Air Mass Flow Simulation conditions: Engine Configurations: No eSC No eSC No eSC eSC electric Power: 1.2 kW; 1.8 kW; 3 kW & 5 kW Test conditions: eSCs eSCs From 2 to 10bar BMEP @ 1500rpm EGR rate: from 50 to 28% Delta = 100 K No eSC FEV estimation : 10%~20% Nox reduction eSCs Results will vary depending on application Results: eSC increases the air flow during transient. It improves the performances AND reduces the temperature increase (-100°C in this case) which is one main factor on the NOx production * Valeo estimate, non contractual data, pending applications, will vary per vehicle application Property of Valeo – Duplication Prohibited Engine Expo 2016 - Stuttgart May - June 2016 I 11 Board net requirement : 48V Dual Battery example Regen/Boost 48V Network DC/DC converter 2,5kW Reversible StarterGenerator 10-12kW Regen Boost Stabilized 12V Network 12V loads 48V loads 12V Lead acid battery 12V + 48V Basic Set 48V battery pack (Li-ion) 2 batteries : allows engine stop and address safety issues Dual battery required for regen and boost (coasting compatible) One battery dedicated to safe network (sensitive loads) One battery dedicated to high current managing (regen & boost) Each battery specification adapted to its own use Property of Valeo – Duplication Prohibited Engine Expo 2016 - Stuttgart May - June 2016 I 12 Electrical board net : modular building 12V -> 48V 12V “regen” network Reversible Machine Starter + Alternator 12V Starter 12V Battery 1 12V “clean” network Optional Piloted switch 12V NON Sensitive Loads 12V Sensitive Loads 12V Battery 2 12V + 12V Basic Set 12V “regen” network Reversible Machine Starter + Alternator 12V Starter 12V Battery 1 12V “clean” network Optional Piloted switch 12V NON Sensitive Loads eSC 12V + 12V Extented Set DCDC 48-12 V 48V “regen” network 12V Sensitive Loads 12V Battery 2 12V “clean” network 12V Sensitive Loads Reversible Machine 48V 12V + 48V Property of Valeo – Duplication Prohibited 48V Battery 48V NON Sensitive Loads 12V Battery eSC Engine Expo 2016 - Stuttgart Starter May - June 2016 I 13 Electrical board net : 48V modular building Regen/Boost 48V Network DC/DC converter 2,5kW Reversible StarterGenerator 10-12kW Regen Boost Stabilized 12V Network 12V loads 48V loads 12V Lead acid battery 12V + 48V Basic Set 48V battery pack (Li-ion) Regen/Boost 48V Network DC/DC converter 2,5kW Reversible StarterGenerator 10-12kW Active susp. PTC Regen Boost Electric supercharger Heated WS Stabilized 12V Network 12V loads 12V Lead acid battery Electric AC compressor 48V battery pack (Li-ion) 12V + 48V Extended Board net Property of Valeo – Duplication Prohibited Engine Expo 2016 - Stuttgart May - June 2016 I 14 Emachines & Electronics Building Blocks overview 12V Hyb Arch 48V 300V Belt Belt Beltless Belt Beltless (P1) (P1) (P3) Gearbox (P4) Driveline Motor Motor (P1) (P3) Gearbox (P4) Driveline Motor Motor Rotor Type 1 Type 1 Type 1 Type 2 Type 2 Type 2 Type 2 Type 2 Stator Type 1 Type 1 Type 2 Type 2 Type 2 Type 2 Type 3 Type 3 Power module Type 1 Type 2 Type 2 Type 2 Type2 Type 3 Type 3 Type 3 Inverter Type 1 air cooled Type 2 air cooled Type 2 Air/water cooled Type 2 Oil cooled Type 2 Oil cooled Type 3 Air cooled Type 3 Oil cooled Type 3 Oil cooled Property of Valeo – Duplication Prohibited Engine Expo 2016 - Stuttgart May - June 2016 I 15 12+12V & 48V Potential Road Map First 12V application : Stop & Start 48V mild hybrid : more power and more energy available First and easier step : belt e-machine. % CO2 Reduction Systems CO2 gains / cost position 80 70 60 50 40 30 20 10 STT 0 system cost Property of Valeo – Duplication Prohibited Engine Expo 2016 - Stuttgart May - June 2016 I 16 12+12V & 48V Potential Road Map An extension to the 12V field : 12+12V gateway to hybrid functions and coasting % CO2 Reduction Systems CO2 gains / cost position 80 70 60 50 40 30 20 10 STT + Regen + Coasting 0 system cost Property of Valeo – Duplication Prohibited Engine Expo 2016 - Stuttgart May - June 2016 I 17 12+12V & 48V Potential Road Map A better cost / CO2 gain ratio than high voltage systems 48V : An increasing potential with boosted hybrid and power devices electrification A continuous extension : accessories electrification, P3/P4 hybrid architectures, new concepts…. % CO2 Reduction Systems CO2 gains / cost position 80 70 60 50 40 30 20 10 0 system cost Property of Valeo – Duplication Prohibited Engine Expo 2016 - Stuttgart May - June 2016 I 18 Conclusion Hybridization: a necessity for CO2 reduction Cost is always a driver : China 2020 (cars only):106 Affordable cars require simpler / cheaper solutions i-Stars 12V Battery 1 Modular Electric Architectures & topology as way to reduce integration cost Start er Extended 12V & 48V mild hybrid systems address basis hybrid functions and allow superior fuel economy for best value equation 100 50 Boosted 12+12V & 48V hybrid with electric supercharger 0 Extended downsizing and downspeeding New turbo matching field (turbo lag) Pollutants reduction Fun to drive / high power engines Property of Valeo – Duplication Prohibited Engine Expo 2016 - Stuttgart May - June 2016 I 19 12V Battery 2 (AGM/NiMH) 12V Sensitive loads Scalable solutions for CO2 reduction level adaptation 12V NON Sensitive loads Piloted switch Property of Valeo – Duplication Prohibited Engine Expo 2016 - Stuttgart May - June 2016 I 20