An air-to-fuel ratio (A/F) modulation scheme is presented in which a linear feedback signal is generated from a heated exhaust gas oxygen (EGO) sensor. In this scheme, the engine A/F is modulated with a triangular waveform, and the mean value of the EGO output is obtained using a rolling average filter. The resulting output is linearly related to the exhaust A/F, and is used to provide closed-loop lean A/F operation following a cold start to enhance catalyst light-off and minimize vehicle exhaust emissions. Some engine-dynamometer results obtained using the method are presented.
Closed-Loop Air-Fuel Ratio Control Using Forced Air-Fuel Ratio Modulation
Sae Technical Papers
International Congress & Exposition ; 1998
1998-02-23
Aufsatz (Konferenz)
Englisch
Closed-Loop Air-Fuel Ratio Control Using Forced Air-Fuel Ratio Modulation
British Library Conference Proceedings | 1998
|Closed-loop air-fuel ratio control using forced air-fuel ratio modulation
Kraftfahrwesen | 1998
|Potential for Closed Loop Air-Fuel Ratio Management of a Diesel Engine
SAE Technical Papers | 1999
|Potential for closed loop air-fuel ratio management of a Diesel engine
Kraftfahrwesen | 1999
|Closed-Loop Control of Spark Advance and Air-fuel Ratio in SI Engines using Cylinder Pressure
British Library Conference Proceedings | 2000
|