SI-Engine Control With Microwave-Assisted Direct Observation of Oxygen Storage Level in Three-Way Catalysts

To realize existing emission standards with a reduced amount of noble metals, advanced control strategies for spark ignition (SI) engines are of absolute priority. Such control strategies require precise and accurate information about the actual oxygen storage level of the three-way catalyst needed to reduce emissions. This precision is out of reach for state-of-the-art oxygen storage models on available on-board hardware. A novel approach toward the solution of this problem is the direct determination of the oxygen storage level. This contribution shows how this can be achieved with a model-based microwave measurement system. The method is validated by numerical experiments. It is demonstrated how this approach can be implemented into a new SI engine control algorithm.