The second-generation air-fuel ratio control method has been developed to reduce exhaust gas emissions in accordance with the improvements in catalysts. The control system consists of a feedforward control using a fuel behavior model, a feedback control using an universal exhaust gas oxygen (UEGO) sensor and a feedback control utilizing the heated exhaust gas oxygen (HEGO) sensor. This significantly improves air-fuel ratio tracking performance by feedforward control derived from the models that express the dynamic phenomena and the disturbance attenuation by UEGO feedback controller which compensates for the long dead-time characteristics by the state predictive control. The tracking performance and the disturbance attenuation can be achieved independently by a two-degree-of-freedom structure presented in this paper. The exhaust air-fuel ratio downstream of the catalyst precisely converges to stoichiometry, which maximizes the conversion efficiency of the catalyst. Experimental results on actual vehicles show the effectiveness of presented method.
Development of a New Model Based Air-Fuel Ratio Control System
Sae Int. J. Engines
SAE World Congress & Exhibition ; 2009
Sae International Journal of Engines ; 2 , 1 ; 335-343
2009-04-20
9 pages
Conference paper
English
Control systems , Gases , Catalysts , Oxygen
Development of a new model based air-fuel ratio control system
Automotive engineering | 2009
|2009-01-0585 Development of a New Model Based Air-Fuel Ratio Control System
British Library Conference Proceedings | 2009
|Development of Next-Generation Air-Fuel Ratio Control System, "COSMIC"
British Library Conference Proceedings | 2002
|Development of next-generation air-fuel ratio control system, "COSMIC"
Automotive engineering | 2002
|Development of Next-Generation Air-Fuel Ratio Control System, “COSMIC”
SAE Technical Papers | 2002
|