| 摘要 |
<p>A method for monitoring the performance of a catalytic converter includes the monitoring of output from a first gas sensor (16) positioned upstream from a catalytic converter (12) and a second gas sensor (18) located at a position downstream from the catalytic converter (12). An engine controller (20) receives the output of the first and second gas sensors (16, 18) and also receives estimates of the exhaust gas mass flow rate and the catalyst temperature within the catalytic converter (12). The exhaust gas mass flow rate and the catalyst temperature are used to calculate a mass transfer coefficient that is determinative of the conversion efficiency of the catalytic converter (12). A monitoring parameter is determined using the output of the first and second gas sensors (16, 18), and the monitoring parameter is normalized to the coefficient. The engine controller (20) then accumulates a data set and compares the values of the data set with previously programmed pass/fail criteria to determine the performance of the catalytic converter (12).</p> |
