Estimation of the Instantaneous In-Cylinder Pressure for Control Purposes using Crankshaft Angular Velocity
Onder, Christopher H.
- Working Paper
Instantaneousin-cylinderpressure , a key variable in the improvement of engine performance and reduction of emissions, is not likely to be measured directly in production type engines in the near future. As a countermeasure, a pressureestimation method based on physical first principles fortheestimationoftheinstantaneousin-cylinderpressureof an SI engine using measured crankshaftangularvelocity is presented here. <br/> The approach consists of (a) mapping the model parameters at nominal operating conditions and (b) adapting the model parameters to current operating conditions usingtheinstantaneouscrankshaftangularvelocity . The model reflects all essential effects on in-cylinderpressure , while the simulation time was reduced to 6 milliseconds per cycle on a standard PC. This makes it possible to estimate a cylinder-averaged pressurefor each cycle up to an engine speed of more than 6000 rpm. The estimated in-cylinderpressure is available with a delay of one engine cycle. <br/> The model has been compared to a benchmark pressureestimation method. Further, the model has been validated in simulation and against measured data for steady-state and transient operation. The model shows good accuracy, while the computational effort is promising for real-time applications. Furthermore, the model needs little calibration effort due to its physically based nature. Mehr anzeigen
Zeitschrift / SerieSAE Technical Papers
Organisationseinheit03286 - Guzzella, Lino / Guzzella, Lino