Individual cylinder air-fuel ratio control with a single EGO sensor

An approach to achieving uniform cylinder-to-cylinder air-fuel ratio control in the face of injector mismatch and unbalanced airflow due to engine geometry is presented. A key feature of the proposed method is that it functions well with the switching-type exhaust gas oxygen sensor commonly used in automobiles. The controller design, from modeling to experimental implementation in a dynamometer test facility, is documented. A method for achieving an extended operating region based on scheduling the sampling is described.>