Dear members of TF WLTP Coasting,
here the minutes of our Telecon from 06Nov2014:
Participants:
S.Redmann, I.Riemersma, , H.Steven, T.Fujiwara, T.Yamaguchi, E.Collot, S.Malfettani
OEMs: A. Feucht, P.Casals, L.Bigi, C. Griard, F.Grisi, L.Bartsch, T.Vogel
Tier1: A.Christ, N.Poertner, Mr.Dimitris (Denso),
Planned Agenda:
1.Review JASIC decision from 06Oct T.Fujiwara, T. Yamaguchi
2.Bosch proposal A.Christ
PSA proposal C.Griard
3.Resume key requirements for the coasting procedure Regions, Member states
4.Discussion about alternative proposals All
5.Decision, if we proceed on WLTP level All
6.Preparation Coasting TF statement for 8th IWG Vogel
7.Find TF speaker for the presentation in Pune
8.Next Steps, Next Meeting
If “data process only” solution is denied:
-Discuss next steps to organize TF within EU Steininger
-Optional (supplemental test): Show WLTC deceleration analysis with conclusions on coast sequences Vogel
1.Review of JASIC decision, distributed 06Oct by Yamaguchi-san:
- Japan follows decision made during WLTP-IWG 7th meeting (no cycle modification but continue to discuss data process only).
- Japan opposes supplemental test, since this proposal practically means “modification” of cycle and Japan also thinks the regional requirement shall not be beyond the framework of current gtr.
T.Fujiwara explained, that the term “discuss data process only” is copied from the Geneva minutes and does not exclude any other solution.
The so far discussed supplemental test in the previous meeting falls under category b.) and is opposed. PSA asked Japan to propose a principle for a test where Japan is willing to support.
2a. Bosch showed the Presentation in the Annex. The proposal does not require any supplemental CO2 measurement, just a proof of coasting implementation parameters used in the algorithm by running a Speed profile in Coast mode.
Thereby also the effectiveness of coasting implementation is taking effect on the CO2 gain.
Methodology (slide 3), Calculation details (5), and Post Calculation (6,7) parameters have been shown and explained in a detailed conversation.
An example (8) showed in time domain of the WLTP, how the calculation works. Bosch agreed on request to deliver the Excel-File behind this Diagrams (see Annex)
a second, more independent part is the determination of the Coast Time Share (CTS). This parameter represents real driving behavior and implementation parameters which effect the driver behavior (Coast indication, Navi, …)
The CTS needs confirmation by additional tests, representing urban, suburban, flat & mountain area. This confirmation is on the time critical path of the TF activity until mid 2015 to reach here a solid number.
Because the Bosch proposals needs time resolved CO2 from the WLTP type1 test, proposals where made (16-18) how to solve this. Similar solutions are discussed in RDE regulation and NEDC Correlation.
Overall, the proposal was seen positive also in the light of “Changing the speed profile of the WLTP” . No showstoppers have been raised.
However, the CTS has to be determined with care, that coasting will not show more benefit than in real driving.
2b. PSA showed a proposal which modifies the original WLTP speed trace on basis of similar distance for every major speed minimum in the cycle.
The so modified cycle can either be tested differentially with 2 warm supplemental tests or with an additional cold test. The determined difference to the unmodified WLTP would then be weighted with a usage factor.
The benefit of this proposal is, that the rules can be adapted to all WLTP classes and regional definitions (skip phases, etc) automatically.
Concerns have been raised that this procedure modifies directly the original speed trace. Also the test effort is doubled or even more.
4. Discussion on the new proposals:
Both proposals, Bosch & PSA are asked to be more deeply studied by participants, so that a down selection (if not anyhow done by contracting parties) can be done next meeting or when all technical questions are resolved.
Iddo Riemersma commented the Bosch proposal to be ok with the first (WLTP calculation) part, but requested the CTS determination to be on the save side towards less test procedure gain then real driving gain.
Although he also sees the Bosch proposal as an indirect cycle modification, he is in support to the Bosch proposal. The team made clear, that any measureable benefit directly or indirectly is a cycle modification.
All concluded that the PSA proposal is a direct cycle modification, but has positive aspects in being directly linked to any version of WLTC class as well as region.
A usage factor is required (similar to Bosch CTS), so that this work is common with the Bosch proposal as well as the previously discussed differential test procedure.
Heinz Steven mentioned that no coast capable vehicles have been part of vehicle fleet data where the WLTC was derived from. If so, the WLTC would have looked differently in the deceleration phases.
Conclusion here is, that IWG clearly excluded any WLTC modification in this phase of the WLTP, so that a certain indirect cycle modification for coasting vehicles will be common to all proposals.
T.Fujiwara agreed to deliver feedback by 10Nov, which of the new two proposals has potential to get Japans support.
5. Decision: final decision was not possible in the meeting.
S. Redmann made clear, that a clear opposing of Japan will lead to close the TF work unless other regions are clearly support the proposal. In this case political solutions have to be found. Therefore India and EU are requested in advance to 8th IWG to state their position to the proposals (put India on the distribution list)
T.Fujiwara made clear that JASIC will give a feedback on coasting on 07Nov.
6. Dependent on the regions reactions the 8th IWG presentation will recommend either closing the TF or proceeding in the direction of the remaining proposals.
T.Vogel will prepare the Pune presentation on 12Nov for review by H.Steven / A.Feucht and final version until 14Nov to S.Redmann
7. T. Vogel will not travel to Pune. Heinz Steven volunteers to represent the Coasting TF in 8th IWG and hold the presentation. Fall back is Anette Feucht.
8.T.Fujiwara will present new proposals in JASIC meeting Friday 07Nov. JASIC shall decide if they can support one or both proposals. (same process as on previous proposal) Feedback awaited until 10Nov.
EU meets on Monday 10Nov and shall also give feedback. K.Steininger to reserve some time in agenda or roundtable. Participating TF members to give details if needed.
Both feedbacks shall be part of the presentation for 8th IWG in Pune.
India shall be informed on the status of the TF before Pune. T.Vogel to add Mr. Nakhawa to the distribution and contact him the week of 10Nov
Dependent on 8th IWG decision: New Setup of Coasting TF (EU only focus). Decision on time critical fleet tests is required to determine Coast share in real world driving.
Next meeting shall be early December. It will be a 3 hour telecon from 9-12 EU time. A Doodle Link with date proposals will be sent by T.Vogel
Mit freundlichen Grüßen
Thomas Vogel
Senior Expert WLTP
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Adam Opel AG, IPC R3-06, D-65423 Ruesselsheim
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