Modellbasierte Bedatungsmethodik für moderne On- und Off-Highway- Motoren

The complexity of engines and aftertreatment systems increased considerably with implementation of the emission standards Euro VI for on-highway commercial vehicles and EU Stage 4 for off-highway mobile machinery. The requirement to achieve the emission legislation while maintaining or improving fuel consumption and guaranteeing high robustness poses a high demand on the selection and optimization of components, the development of control algorithms as well as on the calibration process. In addition, there is a high variety of variants for different vehicles and machines for which an optimal setting needs to be found. A high amount of testing hours on the engine dyno and test equipment is necessary with conventional methods. Especially calibration for extreme conditions as high altitude, cold and warm climate require cost-intensive special test facilities or vehicle/machine testing.

Model-based calibration methods offer an answer to these challenges. Data-based and physically-based models can be used in an efficient way to create base calibrations that have to be only fine-tuned by engine dyno or vehicle testing. The model-based calibration process also offers the possibility to create more robust data sets for certain functionalities. While the reduction of development time is a general goal, the focus of the model based calibration process is on the reduction of testing time as well as on improved robustness.

In this article, the model-based calibration process with its corresponding tools will be presented. The methodology will then be further discussed with three examples for calibration tasks for on- and off-highway engines and aftertreatment systems.