U OF M COLLEGE OF ENGINEERING
CONTROL SEMINAR SERIES
WINTER TERM 1998

Professor Anna Stefanopoulou

Mechanical and Environmental Engineering
University of California/Santa Barbara

anna@engineering.ucsb.edu

Friday, March 27, 1998
4:00 - 5:00 pm
1200 EECS

Title: Multivariable Controller Architecture for Advanced Technology Engines

• Abstract
  
  The global need for improved fuel economy and reduced emissions often requires innovative mechanical engine configurations (new actuators) that introduce additional design parameters (control variables) used to optimize the engine performance. These new actuators result in highly complex powertrains with significant coupling between subsystems thus posing challenging multivariable control problems. In this talk we address the fundamental question of defining a low complexity controller architecture for these advanced technology engines.

  This talk will take you through the stages of a recently developed linear multivariable design methodology applied to the control development of a Ford experimental diesel engine equipped with variable geometry turbocharger: (i) identify the system inherent limitation as it arises from the engine thermodynamic properties and hardware constraints, (ii) analyze the implications of this limiting feature to the feedback control design, and (iii) specify a controller architecture with minimum set of sensors and calibration parameters. We show that a controller designed using this architecture has favorable robustness properties. In particular, we maintain good performance under large model uncertainty and large errors in the set points strategy generated by a higher level optimization layer. Furthermore, this architecture enables us to achieve fast torque response, low feedgas emissions and no visible smoke production. These improvements are obtained by coordinating the fuel command, the variable geometry turbocharger and exhaust gas recirculation. Simulations and experimental results on an engine-dynamometer facility in Dunton, England will be used to demonstrate our conclusions.

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  Biosketch

  
  Anna Stefanopoulou graduated from the National Technical University of Athens (NTUA) in 1991 with a Diploma in Naval Architecture and Marine Engineering. She received two M.S. degrees in Naval Architecture and Marine Engineering, and Electrical Engineering and Computer Science at the University of Michigan in 1992 and 1994 respectively. In 1996 she received her Ph.D. in Electrical Engineering and Computer Science at the University of Michigan.

  As a naval architect at NTUA and the University of Michigan she designed propulsion systems for medium range fishery vessels and investigated applications of fuzzy logic in a vessel path controller and marine engine control. She worked at the Ford Research Laboratories, where she analyzed the impact of multivariable controller structures to advanced technology automotive engines. Her algorithms were implemented and tested in experimental vehicles.

  she is presently an Assistant Professor at the Mechanical and Environmental Engineering Department at the University of California. Dr. Stefanopoulou is Vice-chair of the Transportation Panel in ASME Dynamic Systems and Control Division and a recipient of a 1997 NSF CAREER award. Her research interests are in multivariable feedback control, modular controller architectures for industrial applications, and powertrain modeling and control.

© UofM College of Engineering Control Research Group - December 1997
bethi@umich.edu