This content is not included in
your SAE MOBILUS subscription, or you are not logged in.
Improving Speed and Accuracy of Gasoline and Diesel Engine Testing via Closed-Loop Combustion Control
Technical Paper
2012-01-0902
ISSN: 0148-7191, e-ISSN: 2688-3627
Annotation ability available
Sector:
Language:
English
Abstract
To improve the speed and accuracy of engine testing, the spark
(gasoline)/injection (diesel) timing can be optimized based on the
location of the 50% mass fraction burn point (α50) rather than the
traditional approach of "sweeping" timing to find the
most efficient point. Results from both gasoline and diesel engines
show that setting α50 to around 8° ATDC gives optimum efficiency
for most circumstances. An exception is the case of highly unstable
combustion, where the misfire rate may also be strongly dependent
on timing. For diesel engines this method is effective in finding
the timing for best efficiency but in practice the chosen injection
timing may be driven more by the need to optimize emissions.
This technique has been implemented by incorporating a burn
angle controller into the MAHLE Flexible ECU (MFE), a powerful and
highly adaptable engine controller. The MFE includes the burn angle
calculation (based on cylinder pressure signals) as well as the
main control strategy in a single robust unit, allowing for
straightforward test bed or vehicle operation of gasoline and
diesel engines. The burn angle controller also takes account of
knock and cylinder pressure limitations.
A high octane fuel demonstrator car was developed using the MFE
for the remapping of spark and other parameters. Optimum spark
timing was found by the burn angle controller while operating the
engine at different loads and speeds on a chassis dynamometer,
without needing to remove the engine from the vehicle. The remapped
engine delivered 15-20% more torque at low to medium speeds than
the baseline engine (at the same boost pressure), while reducing
fuel requirement due to lower exhaust temperatures. This could be
felt as much stronger vehicle performance and improved flexibility
in high gears.
Recommended Content
Authors
Topic
Citation
Cains, T., Pates, D., and Warth, M., "Improving Speed and Accuracy of Gasoline and Diesel Engine Testing via Closed-Loop Combustion Control," SAE Technical Paper 2012-01-0902, 2012, https://doi.org/10.4271/2012-01-0902.Also In
References
- Brooks, T. Lumsden, G. Blaxill, H. “Improving Base Engine Calibrations for Diesel Vehicles Through the Use of DoE and Optimization Techniques,” SAE Technical Paper 2005-01-3833 2005 10.4271/2005-01-3833
- Liebig, D. Krane, W. Ziman, P. Garbe, T. et al. “The Response of a Closed Loop Controlled Diesel Engine on Fuel Variation,” SAE Technical Paper 2008-01-2471 2008 10.4271/2008-01-2471
- Cooper, J “Comparison between Mapping MBT versus 50% mass fraction burn MBT” Ford Motor Co. Report November 1997
- Hillion, M. Buhlbuck, H. Chauvin, J. Petit, N. “Combustion Control of Diesel Engines Using Injection Timing,” SAE Technical Paper 2009-01-0367 2009 10.4271/2009-01-0367
- PROtroniC from AFT Atlas Fahrzeugtechnik http://www.aft-werdohl.de/
- TargetLink from dSPACE http://www.dspace.com
- Brunt, M. Pond, C. “Evaluation of Techniques for Absolute Cylinder Pressure Correction,” SAE Technical Paper 970036 1997 10.4271/970036
- Schiefer, D. Maennel, R. Nardoni, W. “Advantages of Diesel Engine Control Using In-Cylinder Pressure Information for Closed Loop Control,” SAE Technical Paper 2003-01-0364 2003 10.4271/2003-01-0364
- Korte, V et al. “MAHLE-Bosch Demonstrator Vehicle for Advanced Downsizing” 19. Aachener Kolloquium Fahrzeug- und Motorentechnik October 2010
- Gurney, D Genieser, P “Simulation and Optimisation of a Variable Valvetrain System for a Compression Ignition Engine” VDI conference “Ventiltrieb und Zylinderkopf” November 2010