Estimation of Air Fuel Ratio of Individual Cylinders in SI Engines by Means of MISiC Sensor Signals in a Linear Regression Model

Metal insulator silicon carbide field-effect devices, MISiC sensors, with catalytic metal gates of TaSi_x + Pt have been evaluated as fast linear lambda detectors. Application areas are for example engine cold start and cylinder specific lambda transient detection. The sensor is placed in the exhaust manifold system, where the branches from the different cylinders are joined. By using a linear regression model the MISiC sensor could predict a lambda value, chosen randomly as one of six values between 0.93 and 1.03. Specially built laboratory equipment, Moving Gas Outlet (MGO), was used to estimate the sensor response time.