1 / 11

12 V SoC – Monitoring - Assessment of Tolerances

Explore precise monitoring methods and correct CO2 emission values for optimal performance in Audi vehicles. Assessments & proposals by Dr. Mühlberger, Dr. Bergmann, and Dr. Kolesa at AUDI AG.

ncausey
Download Presentation

12 V SoC – Monitoring - Assessment of Tolerances

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. WLTP-DTP-LabProcICE-105 12 V SoC – Monitoring - Assessment of Tolerances Audi AG 8.11.2011

  2. Regulation R 101 Dr. F. Mühlberger, Dr. M. Bergmann, Dr. Kolesa AUDI AG 5.3. Test results 5.3.1. The test results (fuel consumption C [l/100 km] and CO2-emission M [g/km]) of this test are corrected in function of the energy balance ΔEbatt of the vehicle’s battery. The corrected values (C0 [l/100 km] and M0 [g/km]) should correspond to a zero energy balance (ΔEbatt = 0), and are calculated using a correction coefficient determined by the manufacturer as defined below. … 5.3.1.1. The electricity balance Q [Ah], measured using the procedure specified in appendix 2 to this annex, is used as a measure of the difference in the vehicle battery’s energy content at the end of the cycle compared to the beginning of the cycle….

  3. Regulation R 101 (ctd) Dr. F. Mühlberger, Dr. M. Bergmann, Dr. Kolesa AUDI AG 5.3.2. Under the conditions below, it is allowed to take the uncorrected measured values C and M as the test results: • 1) in case the manufacturer can prove that there is no relation between the energy balance and fuel consumption, • 2) in case that ΔEbatt always corresponds to a battery charging, • 3) in case that ΔEbatt always corresponds to a battery decharging and ΔEbatt is within 1 per cent of the energy content of the consumed fuel (consumed fuel meaning the total fuel consumption over 1 cycle). The change in battery energy content ΔEbatt can be calculated from the measured electricity balance Q as follows: ΔEbatt = ΔSOC(%) ·ETEbatt ≅ 0.0036·|ΔAh|·Vbatt = 0.0036·Q·Vbatt (MJ) with ETEbatt [MJ] the total energy storage capacity of the battery and Vbatt [V] the nominal battery voltage.

  4. Regulation R 101 (ctd) Dr. F. Mühlberger, Dr. M. Bergmann, Dr. Kolesa AUDI AG 5.3.3. Fuel consumption correction coefficient (Kfuel) defined by the manufacturer 5.3.3.1. The fuel consumption correction coefficient (Kfuel) shall be determined from a set of n measurements performed by the manufacturer. This set should contain at least one measurement with Qi < 0 and at least one with Qj > 0. ….. …..

  5. Equipment for Monitoring of SoC 0,1% rdg and 0,2% f.s. 0,5% rdg and 0,05% f.s. rdg accuracy (0,12+0,52) = 0,51 % f.s. accuracy (0,22+0,052) = 0,21 % f.s. = full scale rdg = reading Error depends on full scale and actual values Dr. F. Mühlberger, Dr. M. Bergmann, Dr. Kolesa AUDI AG

  6. Theoretical approach – 200 A over NEDC Current constant @ 200 A Max dev. = 0.48 Ah Dr. F. Mühlberger, Dr. M. Bergmann, Dr. Kolesa AUDI AG

  7. Theoretical approach – instationary test, 3 Ah over NEDC Max dev = 0.16 Ah (In WLTC ~ 5 Ah corresponds to DEbatt = 1% Energy of consumed fuel @ ~100 g/km CO2) Dr. F. Mühlberger, Dr. M. Bergmann, Dr. Kolesa AUDI AG

  8. Tolerance of CO2-Measurement With improved WLTP procedures and reduced tolerances an overall tolerance of 2 % in CO2 measurement is estimated. Results of Validation Phase 2 and Correlation will provide further evidence Dr. F. Mühlberger, Dr. M. Bergmann, Dr. Kolesa AUDI AG The error in the determination of CO2 is a result of tolerances in various systems within the complete emission test procedure: • Tolerance of measurement equipment • Span Gas • Linearization of Analyzer • Span Gas Divider • Dyno specifications (tolerances) • Tolerance of vehicle (e.g.) • Battery energy management • (charging/decharging) • Operational strategies (adaptions etc.) • Reference fuel (density) • Tolerance of lab processes • Speed trace – shifting points • Soak temperature

  9. Assessment of Tolerances for Correction of CO2 as f(SoC) Application of R101 provision Dr. F. Mühlberger, Dr. M. Bergmann, Dr. Kolesa AUDI AG

  10. Conclusion • The error in the determination of electrical charge with an typical ammeter consists of full scale and reading error. For a typical current of a conventional engine it is assessed at 6 %. The error in the determination of CO2 is estimated at minimum 2 % over the whole chain of measurement equipment, vehicle and lab process. • For a vehicle emitting 100 g/km CO2 in WLTC Cycle,DEbatt of 1 % of consumed fuel energy is about 5 Ah. The tolerance of measured energy - depending on charging strategy - is about 0.3 Ah. • For correction of CO2 following R101 the ratio measurements at different DEbatt of the low voltage batteries have to be performed (feasibility of this proposal for low voltage batteries is still to be evaluated) • The assessed tolerances of CO2 and SoC measurement result in an overall tolerance in the determination of the ratio CO2 / DEbatt of about 60 %. • The correction process for CO2 as f(DEbatt) for a low voltage battery is still very much uncertain. Further data have to be provided through VP2 Dr. F. Mühlberger, Dr. M. Bergmann, Dr. Kolesa AUDI AG

  11. Proposal Dr. F. Mühlberger, Dr. M. Bergmann, Dr. Kolesa AUDI AG Options: Make no proposal from OICA (Tuev Nord proposed following R101) Apply R101, but stay with a correction threshold of DEbatt > 2 % of consumed fuel energy for low voltage batteries monitoring. Further evidence will be available after Validation Phase 2 and WLTP Correlation. Use of a fix correction function dependent on used battery energy (1 % of consumed fuel energy = 1,6 g/km CO2) without threshold. …..

More Related