| A set of transient experiments were performed on a gasoline test engine, with a focus on air to fuel ratio (AFR) tracking during throttle transients. The experiments were performed with two different fuel injection controllers. First, the GM Powertrain Control Module (PCM) was used, followed by the same transient experiments using a model-based controller developed in LabVIEW™. The excursions from a stoichiometric AFR were compared. The LabVIEW™ controller, including a fuel film compensator and a feedforward controller, decreased the duration of the AFR excursions during throttle transients, when compared to the GM PCM. The results indicate that further decreases in the duration and magnitude of AFR excursions would be achieved with a faster engine sensor sampling rate. Overall, the LabVIEW™ controller and fuel film compensator were calibrated quickly and easily, and were able to provide similar AFR tracking performance as the GM PCM. |
