Coasting in WLTP BOSCH proposal comfortable safe clean

Coasting in WLTP: BOSCH proposal comfortable safe clean and efficient Invented for life Coasting (=Sailing) in WLTP: BOSCH proposal Dr. Ansgar Christ Gasoline Systems Advanced & System Engineering Customer Gasoline Systems 1 GS/ESC | 21/05/2014 | © Robert Bosch Gmb. H 2014. All rights reserved, also regarding any disposal, exploitation, reproduction, editing, distribution, as well as in the event of applications for industrial property rights.

Coasting in WLTP: BOSCH proposal Motivation Coasting (=Sailing) means driving a vehicle with open power train, i. e. use natural deceleration, when ICE power demand is low with engine idling or engine off veh. speed è increased rolling distance due to eliminated engine drag fuel cut off Coasting rollingdistance è Coasting technology (esp. w/ engine off) enables significant CO 2 savings in real life “Natural” usage for the driver: Just release gas pedal Coasting occurs in average 20… 30% (average vehicle) of the total driving time è In homologation test cycles a vehicle has to follow the given speed profile as close as possible. Coasting is nearly impossible. Problem to solve: Provide a simple methodology to quantify real-life Coasting benefit in WLTC which is easily integrated into WLTP GTR? Gasoline Systems 2 GS/ESC | 21/05/2014 | © Robert Bosch Gmb. H 2014. All rights reserved, also regarding any disposal, exploitation, reproduction, editing, distribution, as well as in the event of applications for industrial property rights.

Coasting in WLTP: BOSCH proposal: General outline Idea: • Coasting occurs whenever power demand to ICE is low! • Account low power phases in test cycle with zero/idle consumption! è Using same measurement of the vehicle on dyno according WLTP type approval testing conditions Time resolved recording of fuel consumption necessary è Identify phases with low engine power demands using a power threshold & mark these phases as Coasting phases. è Choose the power threshold so that Coasting time share in cycle matches average Coasting time chare in real life. è Subtract respective zero/idle fuel consumption for identified Coasting phases from the original fuel consumption Gasoline Systems 3 GS/ESC | 21/05/2014 | © Robert Bosch Gmb. H 2014. All rights reserved, also regarding any disposal, exploitation, reproduction, editing, distribution, as well as in the event of applications for industrial property rights.

Coasting in WLTP: BOSCH proposal probability [-] Engine operating points with Coasting engine off Simulation WLTP compact class GDI T/C 1. 4 l, 90 k. W 6 -gear MT Start/Stop shows many low power (<5 k. W) operating points Coasting engine off: shift of low power towards zero-power & zeroengine speed operating points engine speed [rpm] è With engine power [k. W] probability [-] Gasoline Systems 4 è Base GS/ESC | 21/05/2014 | © Robert Bosch Gmb. H 2014. All rights reserved, also regarding any disposal, exploitation, reproduction, editing, distribution, as well as in the event of applications for industrial property rights.

Coasting in WLTP: BOSCH proposal probability [-] Engine operating points with Coasting engine idling Simulation WLTP compact class GDI T/C 1. 4 l, 90 k. W 6 -gear MT Start/Stop shows many low power (<5 k. W) operating points Coasting engine idling: shift of low power towards zeropower & idlingengine speed operating points engine speed [rpm] è With engine power [k. W] probability [-] Gasoline Systems 5 è Base GS/ESC | 21/05/2014 | © Robert Bosch Gmb. H 2014. All rights reserved, also regarding any disposal, exploitation, reproduction, editing, distribution, as well as in the event of applications for industrial property rights.

Coasting in WLTP: BOSCH proposal Summary è Basic idea of BOSCH proposal: • Follows the logic of coasting in real life driving • Quantifies coasting fuel consumption benefit on the basis of original WLTP type approval test measurement è Proposal matches real life benefits No need for complicated cycle modification No need for speed tolerance widening One set value only: Coasting time share è Proposal can be easily integrated into WLTP GTR. No need for additional, special modified test cycle on dyno. WLTP Task force “Sailing” should consider BOSCH proposal for further work. Gasoline Systems 6 GS/ESC | 21/05/2014 | © Robert Bosch Gmb. H 2014. All rights reserved, also regarding any disposal, exploitation, reproduction, editing, distribution, as well as in the event of applications for industrial property rights.