This content is not included in
your SAE MOBILUS subscription, or you are not logged in.
Optimal A/F Ratio Estimation Model (Synthetic UEGO) for SI Engine Cold Transient AFR Feedback Control
Annotation ability available
Sector:
Language:
English
Abstract
A new method to estimate instantaneous A/F ratio and use the estimation as a feedback signal to control AFR during cold transients, before the oxygen sensor is functional, has been realized by a on-board PCM for a vehicle with a 4.6L, V8, PFI engine [4, 6]. Different AFRs cause variations in flame propagation, causing fluctuations in the effective torque. When a known AFR disturbance is induced into an engine system, a corresponding crankshaft angular velocity fluctuation can be detected. A variable derived from this physical phenomenon can be used to characterize the problem. The optimal fuel perturbation signal is designed by a relaxation concept, and the system model is determined by employing a dual-direction screening multivariate stepwise regression analysis. The estimated AFR is used by the PCM in a closed loop control to correct the fuel during cold transients.
Recommended Content
Authors
Citation
Tang, X., Asik, J., Meyer, G., and Samson, R., "Optimal A/F Ratio Estimation Model (Synthetic UEGO) for SI Engine Cold Transient AFR Feedback Control," SAE Technical Paper 980798, 1998, https://doi.org/10.4271/980798.Also In
References
- Gassenfeit E.H. Powell J.D. “Algorithms for Air_Fuel Ratio Estimation Using Internal Combustion Engine Cylinder Pressure,” SAE Paper No. 890300
- Drakunov S. Rizzoni G. Wang Y.Y. “On-line Estimation of Indicated Torque in IC Engines Using Nonlinear Observers,” SAE Paper No. 950840
- Leisenring K.C. Rizzoni G. Samimy B. “Methods for Internal Combustion Engine Feedback Control During Cold-Start,” SAE Paper No. 950842
- Asik J.R. Meyer G.M. Tang X. “A/F Ratio Estimation and Control Based on Induced Engine Roughness,”
- Kao M. Moskwa J.J. “Engine Load and Equivalence Ratio Estimation for Control and diagnostics via Nonlinear Sliding Observers.” Int. J. of Vehicle Design 15 3 4 5 358 368
- Asik J. R. Peters J. M. Meyer G. M. Tang D. X. “Transient A/F Estimation and Control Using a Neural Network” SAE Paper No. 970619
- SAS REG Procedure Software SAS Institute, Inc. SAS Campus Drive, Cary, North Carolina 27513