This content is not included in
your SAE MOBILUS subscription, or you are not logged in.
Improving Transient Torque Response for Boosted Engines with VCT and EGR
Technical Paper
2018-01-0861
ISSN: 0148-7191, e-ISSN: 2688-3627
Annotation ability available
Sector:
Language:
English
Abstract
Modern gasoline engines have increased part-load fuel economy and specific power output through technologies such as downsizing, turbocharging, direct injection, and exhaust gas recirculation. These engines tend to have higher sensitivity to driving behavior because of the steady-state efficiency versus output characteristics (e.g., sweet spot at lower output) and the dynamic response characteristics (e.g., turbo lag). It has been observed that the technologies aimed at increased engine efficiency may improve fuel economy for less aggressive cycles and drivers while hurting fuel economy for more aggressive cycles and drivers. The higher degrees of freedom in these engines and the increased sensitivity make controls and calibration more complex and more important at the same time. With the interactions between the dynamic response characteristics of the powertrain and the driver in mind, a dynamic control strategy for variable cam timing (VCT) and exhaust gas recirculation (EGR) is developed. The strategy allows actuator positions at steady-state optimal values when possible yet a fast response proportional to the driver request in transients. The aim is to strike a balance, which is tunable, between steady state efficiency and transient response. Most of the calibration process is algorithmic and based on standard engine mapping data. Experimental results for fuel economy on drive cycles and performance testing from powertrain and chassis dynamometers for two powertrain configurations are reported. Analysis shows improvements in terms of fuel economy and driver demand tracking on drive cycles as well as improved performance metrics. In particular, it is demonstrated that it is possible to simultaneously improve transient performance and fuel economy.
Recommended Content
Authors
Citation
Hellstrom, E., Jankovic, M., Shelby, M., Pietrzyk, P. et al., "Improving Transient Torque Response for Boosted Engines with VCT and EGR," SAE Technical Paper 2018-01-0861, 2018, https://doi.org/10.4271/2018-01-0861.Also In
References
- Leone , T. , Christenson , E. , and Stein , R. Comparison of Variable Camshaft Timing Strategies at Part Load SAE Technical Paper 960584 1996 10.4271/960584
- Yi , J. , Wooldridge , S. , Coulson , G. , Hilditch , J. et al. Development and Optimization of the Ford 3.5L V6 EcoBoost Combustion System SAE Int. J. Engines 2 1 1388 1407 2009 10.4271/2009-01-1494
- Weaver , C. 2015
- Nazari , S , Middleton , R.J. , Martz , J. , and Stefanopoulou , A.G. The Elusive Consequences of Slow Engine Response on Drive Cycle Fuel Efficiency Proceedings of the 2017 American Control Conference Seattle, WA 2017 5379 5385 10.23919/ACC.2017.7963791
- Jankovic , M. and Magner , S. Optimization and Scheduling for Automotive Powertrains Proceedings of the 2004 American Control Conference Boston, MA, USA 2004 4054 4059 5
- Jankovic , M. , Frischmuth , F. , Stefanopoulou , A. , and Cook , J.A. Torque Management of Engines with Variable Cam Timing IEEE Control Systems 18 5 34 42 Oct 1998 10.1109/37.722251
- Eriksson , L , Frei , S. , Onder , C. , and Guzzella , L. Control and Optimization of Turbo Charged Spark Ignited Engines Proceedings of IFAC World Congress Barcelona, Spain 2002
- Karnik , A.Y. , Buckland , J.H. , and Freudenberg , J.S. Electronic throttle and wastegate control for turbocharged gasoline engines Proceedings of the 2005 American Control Conference Portland, OR 2005 4434 4439 7 10.1109/ACC.2005.1470694
- Wiese , A.P. , Stefanopoulou , A.G. , Karnik , A.Y. , and Buckland , J.H. Model Predictive Control for Low Pressure Exhaust Gas Recirculation with scavenging Proceedings of the 2017 American Control Conference Seattle, WA 2017 3638 3643 10.23919/ACC.2017.7963510
- Gelso , E.R. and Lindberg , J. Air-Path Model Predictive Control of a Heavy-Duty Diesel Engine with Variable Valve Actuation IFAC Proceedings 47 3 3012 3017 2014 10.3182/20140824-6-ZA-1003.01263
- Lee , T.K. and Filipi , Z.S. Nonlinear Model Predictive Control of a Dual-Independent Variable Valve Timing Engine with Electronic Throttle Control Proceedings of the Institution of Mechanical Engineers, Part D: Journal of Automobile Engineering 225 9 1221 1234 2011 10.1177/0954407011407691
- Flärdh , O. , Ericsson , G. . Klingborg , E. , and Mårtensson , J. Optimal Air Path Control During Load Transients on a Spark Ignited Engine with Variable Geometry Turbine and Variable Valve Timing IEEE Transactions on Control Systems Technology 22 1 83 93 2014 10.1109/TCST.2013.2245330