The Whirling Blade and the Steaming Cauldron
Robert E. Bodenheimer, Jr.
California Institute of Technology, 1995
This dissertation applies recent theoretical developments in control
to two practical examples. The first example is control of the primary
circuit of a pressurized water nuclear reactor. This is an interesting
example because the plant is complex and its dynamics vary
greatly over the operating range of interest. The second example is a
thrust-vectored ducted fan engine, a nonlinear
flight control experiment at Caltech.
The main part of this dissertation is the application of linear
parameter-dependent control techniques to the examples. The
synthesis technique is based on the solution of linear matrix
inequalities (LMIs) and produces a controller which achieves specified
performance against the worst-case time variation of measurable
parameters entering the plant in a linear fractional manner. Thus the
plant can have widely varying dynamics over the operating range, a
quality possessed by both examples. The controllers designed with
these methods perform extremely well and are compared to ${\cal
H}_\infty$, gain-scheduled, and nonlinear controllers.
Additionally, an in-depth examination of the model of the ducted fan
is performed, including system identification. From this work, we
proceed to apply various techniques to examine what they can tell us
in the context of a practical example. The primary technique is
LMI-based model validation.
The contribution this dissertation makes is to show that
parameter-dependent control techniques can be applied with great
effectiveness to practical applications. Moreover, the trade-off
between modelling and controller performance is examined in some
detail. Finally, we demonstrate the applicability of recent model
validation techniques in practice, and discuss stabilizability issues.
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Ducted Fan Home Page
Bobby Bodenheimer bobby@hot.caltech.edu
Last modified: Sat Mar 30 15:42:53 1996