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Modeling the Effects of Combustion Variability for Application to Idle Speed Control in SI Engines
ISSN: 0148-7191, e-ISSN: 2688-3627
Published October 21, 2002 by SAE International in United States
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Combustion in the cylinder of a spark ignition engine, particularly under low load conditions, is subject to cycle-by-cycle variations due to factors such as mixture quality and quantity and internal exhaust gas recirculation. The major result of this phenomenon is an increase in the variability of indicated engine torque at a given engine operating point. Automotive control problems dealing with torque production at low engine loads, particularly the control of idle speed, rely on accurate information about the transfer functions of different engine subsystems, however combustion variability and the effect it has on torque production is often overlooked. In this paper we illustrate the effects that combustion variability at idle has on different transfer functions related to indicated torque, and propose new models for torque production at constant operating points. We also present a model of an in-line, six-cylinder, 4.0 litre Ford engine for use in idle speed simulations and control applications. The integration of combustion variability into an idle speed control framework is also discussed.
CitationManzie, C., Watson, H., and Baker, P., "Modeling the Effects of Combustion Variability for Application to Idle Speed Control in SI Engines," SAE Technical Paper 2002-01-2734, 2002, https://doi.org/10.4271/2002-01-2734.
- Hendricks, E., et al., Modeling of the Intake Manifold Filling Dynamics. SAE Paper 960037, 1996.
- Shrestha, S.O.B. and Karim G.A., Considering the Effects of Cyclic Variations when Modeling the Performance of a Spark Ignition Engine. SAE Paper 2001-01-3600, 2001.
- Proakis, J.G. and Manolakis D.G., Digital Signal Procesing. Principles, Alogrithms and Applications. Second Edition. 1992, New York: Macmillan Publishing Company.
- Ford, R. and Collings N., The Dynamic Effect of Residual Gas Temperature on Combustion Torque at Idle. SAE Paper 2001-01-3558, 2001.
- Cho, D. and Hedrick J.K., Automotive Powertrain Modelling for Control. Transactions of the ASME, 1989: p. 568-576.
- Liu, Y., Strategies for Improving Vehicle Energy Efficiency. PhD Thesis, The University of Melbourne, 1992.
- Moro, D., Cavina N., and Ponti F., In-Cylinder Pressure Reconstruction Based on Instantaneous Engine Speed Signal. Journal of Engineering for Gas Turbines and Power, 2002. 124: p. 220-225.
- Manzie, C., Palaniswami M., and Watson H., Gaussian Networks for Fuel Injection Control. Proceedings of the Institute of Mechanical Engineers: Part D Journal of Automobile Engineering, 2001. 215(10): p. 1053-1068.