KSME International Journal

, Volume 11, Issue 1, pp 88–95 | Cite as

Idle speed modeling and optimal control of a spark-ignition engine

  • Shin Hyuk Joo
  • Kwang Min Chun


A model of engine dynamics is developed. The model is a MISO (Multi Input Single Output) linear model which has two inputs and one output. One input is the spark timing, and the other is the ISCV (Idle Speed Control Valve) position. The output is the angular speed of an engine. The reliability of the developed model is confirmed by comparing the measured response of the engine to step inputs and external disturbance with the simulation results. In order to reduce the steady state error, an integrator state is inserted to the state equation. An engine idle speed controller is designed using optimal control theory based on the model. The performance variation of the controller to the various design parameters is simulated. On the basis of the simulation and the experimental data, the design parameters are determined. The developed controller reduced the idle speed drop caused by an external load change and recovered the desired idle speed in one second.

Key Words

Idle Idle Speed Spark Timing ISCV MISO Linear Model Optimum Control 


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  1. Cassidy, J. F., Athens, M and Lee, W. H., 1980, “On the Design of Electronic Automotive Engine Controls Using Linear Quadratic Control Theory,”IEEE Trans. on Automotive Control, Vol. AC-25, No. 5.Google Scholar
  2. Hendricks, E., and Poulsen, N., 1986, “Minimum Energy Control of Large Diesel Engines,”SAE Technical Paper No. 861191.Google Scholar
  3. Hendricks, E. and Sorenson, S. C., “Mean Value Modelling of Spark Ignition Engines,”SAE Paper 900616.Google Scholar
  4. Hendricks, E. and Sorenson, S. C., “SI Engine Controls and Mean Value Engine Modelling,”SAE Paper 910258Google Scholar
  5. Hendricks, E., 1991, Transient Errors in Classical SI Engine Controllers,American Control Conference (1991 ACC), Paper No. TP-14, 15:00, Heywood, J. B., 1988,Internal Combustion Engine Fundamentals, McGraw Hill.Google Scholar
  6. Kjergaard, L., Nielsen, S., Vesterholm, T. and Hendricks, E., “Advanced Nonlinear Engine Idle Speed Control Systems,”SAE Paper 940974Google Scholar
  7. Kim Jong-Jin, 1994, “A Study of Knock Control Using the Cylinder Block Vibration Signal,”Dept. of Mech. Engineering The Graduate School Yonsei University.Google Scholar
  8. Kim, J. S., 1994, “Linear Control System,” Chung-Mun-Gak.Google Scholar
  9. Morris, R. L. and Powell, B. K., 1983, “Mordern Control Applications in Idle Speed Control,” Paper. No. WA4-11:45,American Control Conference (ACC).Google Scholar
  10. Onder, C. H., Geering, H. P., “Model-Based Multivariable Speed and Air-to-Fuel Ratio Control of an SI Engine,”SAE Paper 930859Google Scholar
  11. Yang Byung-Yul. 1994, “Basic Study of Idle Speed Control in a Spark-Ignition Engine,”Dept. of Mech. Engineering The Graduate School Yonsei University.Google Scholar

Copyright information

© The Korean Society of Mechanical Engineers (KSME) 1997

Authors and Affiliations

  • Shin Hyuk Joo
    • 1
  • Kwang Min Chun
    • 1
  1. 1.Dept. of Mechenical EngineeringYonsei UniversitySeoulKorea

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