Computational Methods for Analyzing and

Controlling Hybrid Systems

Dr. Michiel van Nieustadt

Ford Motor Company

This seminar touches on 2 topics relevant to the control of lean burn engines: cylinder balancing and aftertreatment control.

Cylinder balancing: The limited manufacturing tolerances of high pressure fuel injection systems found on modern direct injection engines lend itself to an on-line adaptation scheme to compensate for injector variability. Since cylinder imbalance affects many measurable signals, different sensors and algorithms can be used to equalize torque production by the cylinders. This part of the presentation compares several adaptation schemes that use different sensors. The algorithms are evaluated on a cylinder-by-cylinder simulation model of a direct injection high speed diesel engine. A proof of stability and experimental results are reported as well.

Modelling and control of active lean NOx catalysts: This part presents a control oriented model of an active lean Nox catalyst for control purposes. Much abuse is covered by the qualifier "control oriented" and this model is no exception. The model does not include spatial variation of temperature and species concentrations, but lumps the characteristics of the catalyst into a few parameters. It accounts for hydrocarbon combustion, storage and release, temperature rise and NOx conversion. Some avenues for active control are explored.

Friday, November 10, 2000

3:30 - 5:00 p.m.

1500 EECS