Optimal A/F Ratio Estimation Model (Synthetic UEGO) for SI Engine Cold Transient AFR Feedback Control Ford Motor Company

Format:

Conference/Event

Author/Creator:

Tang, Xiaoguo, author.

Conference Name:

International Congress & Exposition (1998-02-23 : Detroit, Michigan, United States)

Language:

English

Physical Description:

1 online resource

Place of Publication:

Warrendale, PA SAE International 1998

Summary:

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

Notes:

Vendor supplied data

Publisher Number:

980798

Access Restriction:

Restricted for use by site license