Dual-axis dyno Taskforce Status Report WLTP-IWG meeting April 2016 Iddo Riemersma (T&E) Christoph Lueginger (BMW) WLTP-14-04e

State of play  The taskforce was established at the request of the EU-AdminWG  Purpose is to solve the issues on 2WD/4WD vehicles tested on single and dual-axis dynos for the EU implementation Regulation xxx/2016  Intention is to bring the same text as a proposal to the IWG for adoption into the WLTP GTR  Taskforce includes representatives from the OEMs (VW, Audi, BMW) and TAA’s (RDW, UTAC, TUV), as well as T&E, TNO and the EC.  One teleweb conference was held on 31 March 2016  A text proposal was prepared and circulated for discussion

Discussion items  Requirements to appoint 2WD/4WD vehicles to single/dual-axis chassis dynamometer  Definitions on driven axle, single- and dual-axis chassis dynamometer  Allowing the use of a dual-axis as a single-axis chassis dynamometer  Metric for demonstrating equivalency for testing a 4WD vehicle which is converted to 2WD  Allowing a ‘delta’ for a 4WD vehicle which is converted to 2WD

simulates inertia and load simulates inertia and load simulates inertia and load rotating onlysimulates inertia and load no rotation 4WD "mode" quasi 2WD "mode" 2WD "mode" simulates inertia and load 2-axle dyno facility 1-axle dyno facility vehicle4WD modequasi 2WD mode2WD mode 2WD(X)** X 4WDX-* * apart from described exemptions** on request OEM, with agreement authority Schematic overview of the proposal

Open issues  Should the proposal be more clear on ‘part-time’ 4WD vehicles that have a manual switch to engage 4WD?  Is it necessary to allow a 2WD vehicle at a dual-axis dyno with inertia and road-load simulation on both vehicle axles?  Is it possible to determine a (worst-case) ‘delta’, and under what conditions should it be allowed?  For the previous point, input from IWG is requested to find out if CP’s have a need to test 4WD vehicles at single-axis dynos in the case that equivalency cannot be demonstrated

Outlook  Close the open issues through exchange, or another teleweb conference if necessary  Respond to the output from the IWG on the need for CP’s to test 4WD vehicles at single-axis dynos  Finalize the text proposal and deliver this to the EU-AdminWG  The work of the taskforce is expected to be finalized soon

Text proposal under discussion (1 of 2) Add to the section on definitions in Annex XXI the following paragraphs: "driven axle": An axle of a vehicle is considered to be a driven axle if propulsion energy can be delivered and/or recuperation energy can be drawn from that axle, independent of whether that is only temporarily or permanently possible and/or selectable by the driver. “single-axis dynamometer” is a dynamometer which simulates inertia and road load on the driven axle of a vehicle of which only one axle is driven. In such a case the wheels of the other axle shall not influence the dynamometer measurement. "dual-axis dynamometer" is a dynamometer which simulates inertia and road load on both vehicle axles. Add to the section on ‘Dynamometer operation’ in paragraph of Sub-Annex 6 of Annex XXI the following paragraphs: If the test vehicle has any mode for which under WLTP conditions it is partially or permanently operated with two driven axles over the applicable cycle, the test vehicle shall be tested on a dual-axis chassis dynamometer which fulfils the additional specific requirements according to paragraph 2.3. of Sub-Annex 5. If the test vehicle is only operated with two driven axles in dedicated driver-selectable modes which are not intended for normal daily operation but only for special limited purposes, such as ‘mountain mode’ or ‘maintenance mode’, the vehicle shall be tested on a single-axis chassis dynamometer which fulfills the specific requirements according to paragraph 2.2. of Sub-Annex 5. In all other cases the test vehicle shall be considered to have one driven axle, and shall be tested on a single-axle chassis dynamometer which fulfills the specific requirements according to paragraph 2.2. of Sub-Annex 5.

Text proposal under discussion (2 of 2) At the request of the manufacturer and with the approval of the approval authority, a vehicle which according to paragraph has to be tested on a dual-axle chassis dynamometer may alternatively be tested on a single-axis chassis dynamometer if all of the following conditions are met: a)the test vehicle is converted to have only one driven axle in all modes; b)the manufacturer demonstrates to the approval authority that the CO 2, fuel consumption and/or electrical energy consumption of the converted vehicle is the same or higher as for the non-converted vehicle being tested on a dual-axis chassis dynamometer; c)a safe operation is ensured for the test, e.g. by removing a fuse or dismounting a drive shaft. An instruction on the vehicle conversion and obtaining a safe operation shall be provided on together with the vehicle’s dynamometer operation mode; d)the conversion is only applied to the vehicle tested on the chassis dynamometer, the road load determination procedure shall be applied to the unconverted test vehicle; e)the conversion shall be applied during the entire chassis dynamometer test procedure, including the chassis dynamometer setting procedure and preconditioning tests) If the test vehicle is tested in a mode with only one driven axle, the test vehicle shall be tested on a single-axis chassis dynamometer which fulfils the requirements according to paragraph 2. of Sub-Annex At the request of the manufacturer and with the approval of the approval authority, a chassis dynamometer which fulfils the additional specific requirements according to paragraph 2.3. of Sub-Annex 5 may be used as a single- axle chassis dynamometer if the simulation of inertia and road load is only applied to the dynamometer axle which connects to the vehicle’s driven axle.